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In the past, document writing tools used by document writers are independent from document management and retrieving tools that users use; that is, the writer does not care how the reader will retrieve and leverage the content written by him/her when he/she prepares it. While at the same time, from the information-accessing point of view, users would feel great challenge to get things they really want.
Moreover, at present, computer's capability to understand natural languages is still at a level of word understanding, while for the document management and retrieving tools, there is a need of understanding and semantic capabilities for sentences and even the whole document so as to really satisfy users' requirements. Consequently, according to the present speed in technical development, it is believed that the current document writing, managing and retrieving technology will not be able to evolve to meet the user's information accessing requirements. | {
"pile_set_name": "USPTO Backgrounds"
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With the explosion in communication via the Internet in recent years, there has been a corresponding increase in demand for high-speed bandwidth, such as that provided by optical fibers. In fiber optic communication systems, a fiber that carries optical signals contains asymmetries. These asymmetries result in the optical properties of the fiber not being the same in all directions. Thus, the fiber is birefringent, where the material displays two different indices of refraction. This fiber birefringence causes polarization mode dispersion (PMD).
PMD is measured like a vector quantity, where a differential group delay is the magnitude of the vector and the principal state of polarization (PSP) is the direction. There are two PSPs associated with PMD. The two PSPs propagate at slightly different velocities with the distribution of signal power varying with time.
PMD is a time varying stochastic effect. PMD varies in time with ambient temperature, fiber movement, and mechanical stress on the fibers. Compensating for PMD can be difficult because of the time varying nature and randomness of PMD.
PMD has been shown to be an impairment to the transmission of signals over telecommunication optical fiber at line rates of 10 Gbits/s or above over long distances. Though the problem originates in both optical components and the transmission fiber, the ongoing focus has been PMD reduction in the fiber.
Current processes enable designing and manufacturing optical transmission fiber with very low values of PMD. However, not all manufacturers have access to the intellectual property which is critical to successfully and consistently produce fiber with good PMD performance. Hence, the optical fiber market offers a wide spectrum of quality with little differentiation in specifications. A current challenge for optical cable manufacturers and installers is assessing the true PMD quality of the fiber based on information provided by the fiber manufacturer. In particular, a common question is what fiber/cable qualification procedure should be followed to assure good PMD performance in the installed system.
The traditional specifications on PMD have focused on the link design value (LDV) or maximum differential group delay (DGD-max). These metrics have an inherent weakness, however, of being virtually impossible for a customer to verify. It has become apparent that more information on PMD is required, specific to a customers' fiber order and cable type. Acquiring this information involves careful attention to measurement techniques and correlation of fibers as they move from draw towers through the final installed cable product.
Accordingly, there is a need in the art of optical fiber manufacturing and installation for a system, which provides predictive PMD throughout the manufacturing and installation process. | {
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It is often necessary for a fluoride containing gel or a gel containing another medicament to be applied to the teeth and gums of dental patients. For this purpose, it has been known to form a tray for the application of such a gel. Typically, these trays are disposable and are molded from a closed-cell polyethylene foam. An example of a conventional disposable tray is that sold by Oral-B Laboratories consisting of a unitary tray structure having upper and lower cups as depicted in US. Pat. Nos. Des. 273,893 and 5,211,559, incorporated herein by reference. Each of the cups has a shape which roughly conforms to the upper or lower teeth, i.e., a generally C-shape, and has a concave medicament receiving surface. The cups are secured together by hinge straps which normally maintain the cups in a planar relationship with both medicament receiving surfaces facing in the same direction. A gel is then loaded into the medicament receiving surfaces from a container such as a tube, after which the tray is folded about the hinge straps so that the cups overlie one another with the medicament receiving surfaces facing away from one another. The tray, in this folded state, is then inserted into the patient's mouth. The patient then bites down firmly into the concave medicament receiving surfaces and holds that position until the treatment is completed, after which the unit is removed from the patient's mouth and discarded.
It is important that disposable trays are fabricated from a soft, compliant material to provide a comfortable fit to the user. Early disposable trays were fabricated from a hard vinyl material which met with great complaints. It is also important that these disposable trays also maintain mechanical and chemical integrity during use. For example, disposable foam trays as described above have a tendency to warp and deform during use. This warping can cause the treatment gel to spill or leak from the tray. Furthermore, the hinge element of the tray can sometimes structurally fail, resulting in a very uncomfortable fit for the user. Still further, it is difficult to provide printed ornamentation and labeling on such tray, due to the fact that a wide number of medicament gels must are used in such trays; these medicament pose chemical compatibility concerns. Heretofor, these shortcomings have not been solved Therefore, it is an object of the present invention to provide a disposable dental treatment tray for holding medicament gels which solves these problems.
U.S. Pat. Nos. 4,173,219, 4,376,628, 4,428,373, 5,211,559, and Des. 273,893 discloses a disposable dental tray configurations which can be adapted to the present invention, all incorporated in their entirety by reference.
Treatment gels and foamable solutions containing fluorides and other medicaments, formulated and packaged for filling and application to the teeth and gums of a patient in a dental treatment tray by a dentist are well known. Particularly suited for use in the present invention are the fluoride foam medicated gels described in U.S. Pat. Nos. 4,770,634, 5,071,637 and 5,073,363, incorporated herein by reference. | {
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Various weight measuring devices for measuring the weight of the living body have been conventionally proposed. The proposed device for measuring the weight includes a device in which the function of the weight scale is provided to the body composition meter, where a device for measuring the weight of a pet is proposed as a device defining a reference value through calibration beforehand (see patent document 1). Such pet automatic weight measurement system is described to use the reference value obtained through calibration using a spindle of a predetermined weight in advance.
The 0 kg state that becomes the reference value changes by the installed location, the tilt, and the like of the weight measuring device. The pet automatic weight measurement system described above obtains the reference value through calibration in advance, and thus has error caused by the installing environment after factory shipment.
Measurement of 0 kg is generally carried out before starting the weight measurement to ensure the precision for the weight measuring device. In this case, however, the measurement takes time and the measurement cannot be started right away. Thus, the problem in that each measurement takes time arises.
Patent Document 1: Japanese Unexamined Patent Publication No. 2007-330200 | {
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In order to improve bending fatigue strength for extending bending fatigue life of a gear, it is typical at present to employ surface treatment to introduce a residual compressive stress layer into a tooth root of the gear. The residual compressive stress layer applied to a root surface may interact with tensile stress generated during the operation of the gear, and thus stress amplitude of the root surface is reduced, which may cause a position subjecting a maximum equivalent stress to move toward an interior of the gear. Finally, generation and propagation of cracks on the root surface can be suppressed.
At present, several types of gear surface strengthening techniques can add the residual compressive stress layer, and may be classified, by strengthening mechanism, into phase transformation strengthening, chemical strengthening and mechanical strengthening. Both the phase transformation strengthening and the chemical strengthening involve a complicated heat treatment process, and heat treatment may cause a large deformation and a poor surface accuracy. Moreover, the phase transformation strengthening and the chemical strengthening involve a complicated treatment process and a limited effect.
The mechanical strengthening mainly refers to shot peening strengthening. The shot peening strengthening is a most widely used gear surface strengthening technique. In the shot peening strengthening, high-speed shots are used to impact the root surface, and plastic deformation of the root surface is induced by an impact force from the shots, and in turn a residual compressive stress layer is introduced. Based on the principle of the shot peening, surface shot peening strengthening such as ultrasonic shot peening and laser shot peening has been developed. In the ultrasonic shot peening, mechanical energy is provided for the shots by an ultrasonic vibration device, and a small amount of shots are hit and rebounded repeatedly in the ultrasonic vibration device for transmitting energy of ultrasonic vibration to the root surface, and thus plastic deformation and a residual compressive stress layer are formed. In the laser shot peening, a gear surface is coated with a special coating, and part of the coating is vaporized and expanded by laser induction, and thus a large impact force is generated to impact a root surface, finally, a residual compressive stress layer is added.
In a shot peening strengthening process, an entire tooth (including an end surface, a tooth surface and a tooth root) of the gear is impacted to be strengthened. Since the tooth root has a complicated geometrical shape and a narrow space, and it is difficult to perform ultrasonic shot peening strengthening treatment at the tooth root described above, the ultrasonic shot peening is not applicable at the tooth root, and has no pertinence to tooth root strengthening and has a low efficiency. In the laser shot peening, the area of a surface to be processed per unit time is limited and a cost is high, and thus the laser shot peening is difficult to apply to industrial production. Thus, there is an issue of a poor effect and a low efficiency in use of a shot peening strengthening technique to strengthen the tooth root. | {
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Flooding compositions are materials designed to occupy void spaces in telecommunication cables, such as the void spaces typically found around and between buffer tubes commonly used in fiber optic cables. Additionally, flooding compositions can be used as filling materials to suspend and protect optical fibers inside buffer tubes. Flooding compositions are free-flowing at elevated temperatures (such as those temperatures used when filling a telecommunication cable), and readily gel at lower temperatures to avoid dripping at room temperature. Additionally, easy-to-clean and non-messy flooding compositions are desirable for ease of installation and prevention of environmental contamination. Although advances have been made in the art of flooding compounds, improvements are still desired.
Another important property of a flooding composition is its compatibility with polymer materials used in cable constructions such as polyolefin, i.e., low gel pickup for good property retention and cable longevity. Current commercial flooding compounds are based on synthetic hydrocarbons; they are messy, grease/wax-like materials that stick to surfaces that come in contact with them. In case of a spill, they are not environmentally friendly. The wire and cable industry has a continuing interest in flooding compositions that exhibit reduced stickiness, reduced absorption into materials used in the manufacture of cable components such as buffer tubes, jackets, etc., and more environmental friendly. | {
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1. Field of the Invention
The invention relates to alkenoic acid derivatives, processes for their preparation and their use in medicaments.
2. Background Information
The GB 2 184 121 describes phenethyl sulphides with leukotriene antagonistic properties. The more active compounds of the GB 2 184 121 are insufficiently stable for pharmaceutical use. | {
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Sequence-specific DNA binding proteins, more commonly known as transcription factors, represent a group of molecules within the cell that function to connect extracellular signals to intracellular responses by directly affecting gene transcription. Immediately after an environmental stimulus, these proteins which reside predominantly in the cytosol are translocated to the nucleus where they bind consensus regions in the promoters of various genes and activate or repress the transcription of the respective target gene.
Bc1-6 (also known B-cell CLL/lymphoma 6, zinc finger protein 51 and LAZ3) is a sequence-specific DNA binding transcriptional repressor (consensus DNA-binding site: TTC(C/T)T(A/C)GAA) (Baron et al., Genes, Chromosomes Cancer, 1995, 13, 221-224; Kerckaert et al., Nat. Genet., 1993, 5, 66-70). The gene is expressed in germinal center B- and T-cells and is required for germinal center formation and Th-2 mediated antibody affinity maturation. In addition to cells of B-cell lineage, bc1-6 expression has been demonstrated in muscle tissue and keratinocytes (Kanazawa et al., Pathol. Int., 1997, 47, 600-607). The expression level of bc1-6 is controlled by the antigen receptor via MAP kinase activation which leads to phosphorylation and degradation of bc1-6 by the ubiquitin/proteosome pathway (Niu et al., Genes Dev., 1998, 12, 1953-1961).
Under normal circumstances, bc1-6 mediates transcriptional repression on a wide range of promoters through the process of histone deacetylation and by recruiting (through the BTB/POZ domain) a nuclear hormone receptor co-repressor (SMRT)(Albagli et al., Biochem. Biophys. Res. Commun., 1996, 220, 911-915; Deweindt et al., Cell Growth Differ., 1995, 6, 1495-1503; Dhordain et al., Oncogene, 1995, 11, 2689-2697; Dhordain et al., Proc. Natl. Acad. Sci. U.S.A., 1997, 94, 10762-10767; Dhordain et al., Nucleic Acids Res., 1998, 26, 4645-4651; Seyfert et al., Oncogene, 1996, 12, 2331-2342). It has also been suggested that bc1-6 plays a role in the regulation of apoptosis. Studies in HeLa cells showed that overexpression of bc1-6 induced apoptosis which was preceded by the downregulation of bc1-2 and bc1-X.sub.L, two other apoptosis repressors (Yamochi et al., Oncogene, 1999, 18, 487-494).
Bc1-6 is localized to chromosome 3q27, a region which undergoes a high frequency of translocation events (Ye et al., Cancer Res., 1993, 53, 2732-2735). Deregulation of bc1-6 expression has been shown to occur via translocations with other chromosome sites including those of the 1 g heavy (14q32) or light (2p12) chain loci (Bastard et al., Blood, 1994, 83, 2423-2427; Daudignon et al., Cancer Genet. Cytogenet., 1999, 111, 157-160; Gaidano et al., Blood, 1994, 84, 397-402; Ichinohasama et al., Cancer Genet. Cytogenet., 1998, 104, 19-27; Ohno et al., Jpn. J. Cancer Res., 1994, 85, 592-600; Otsuki et al., Blood, 1995, 85, 2877-2884) as well as through point mutations (Capello et al., Br. J. Haematol., 1997, 99, 168-170; Gaidano et al., Genes, Chromosomes Cancer, 1999, 24, 16-23) and deletions (Bernardin et al., Oncogene, 1997, 14, 849-855; Nakamura et al., Leukemia, 1996, 10, 658-661). These alterations, resulting in aberrant forms of bc1-6, are strongly implicated in the pathogenesis of several types of lymphomas including 30% of diffuse large-cell lymphomas and a fraction of follicular lymphomas (Ye et al., Science, 1993, 262, 747-750). Chromosomal rearrangements involving the bc1-6 locus have also been reported in acute lymphoblastic leukemia (Berger et al., Cancer Genet. Cytogenet., 1996, 86, 76-79) and post-transplant lymphoproliferative disorders (Delecluse et al., Br. J. Haematol., 1995, 91, 101-103).
Currently, there are no known therapeutic agents which effectively inhibit the synthesis of bc1-6 and to date, strategies aimed at investigating bc1-6 function and expression have involved the use of antibodies. Flenghi et al. have used monoclonal antibodies to the altered forms of bc1-6 as diagnostic markers (Flenghi et al., Am. J. Pathol., 1996, 148, 1543-1555; Flenghi et al., Am. J. Pathol., 1995, 147, 405-411). Other methods of detecting the rearrangement of bc1-6 by cleavage and size fractionation are disclosed in U.S. Pat. No. 5,882,858 (Dalla-Favera and Changanti, 1999).
This method is also disclosed in PCT publication WO 94/29343 as well as, in general, nucleic acid molecules that will hybridize to the bc1-6 sequence (Dalla-Favera and Chaganti, 1994).
Consequently, there remains a long felt need for additional agents capable of effectively inhibiting bc1-6 function.
Antisense technology is emerging as an effective means for reducing the expression of specific gene products and may therefore prove to be uniquely useful in a number of therapeutic, diagnostic, and research applications for the modulation of bc1-6 expression.
The present invention provides compositions and methods for modulating bc1-6 expression, including modulation of the aberrant forms of bc1-6. | {
"pile_set_name": "USPTO Backgrounds"
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Heretofore, a communication apparatus has the following problem in digital modulation if an analog signal line and an asynchronous digital signal line are arranged close to each other in the communication apparatus. More specifically, such close arrangement allows toggles in the digital signal to interfere with the analog signal, and thereby sharp peaks sometimes appear in the analog signal. When the analog signal thus influenced by the interference is sampled, the peaks are also taken into the samples. Consequently, the resultant data includes large noise and communication quality deteriorates. To address this problem, one possible way is to take such a measure in the layout process as to avoid signal line arrangement in which digital and analog signal lines are arranged close to each other, for example. However, an increase in the integration degree makes it difficult to take this measure in the layout process. Instead, another possible way is to take a measure using error correction code. However, when the error correction code is used to correct a signal influenced by the interference, the exerted error correction performance is lower than the intrinsic performance level of the error correction code. For this reason, as a method of reducing interference with an analog signal from a digital signal, there is a technique of reducing influence of interference by interpolation processing using a digital filter. This interference reduction technique is disclosed in Japanese Patent Application Publication No. Hei 06-252973. Also there is a technique of reducing influence of interference by performing sampling at timings shifted from originally-designed timings. This interference reduction technique is disclosed in Japanese Patent Application Publications Nos. Hei 09-153802 and 2001-53609.
However, these techniques have a drawback in that the techniques can produce the effects by only when a digital signal of interference origin and sampling clock are synchronous with each other, but cannot obtain good communication quality when the digital signal and the sampling clock are asynchronous with each other. | {
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This disclosure relates generally to cartons and more specifically to cartons formed from carton blanks for enclosing a plurality of containers, such as cans or bottles.
Various cartons in the packaging art enclose a plurality of containers, such as cylindrical cans or bottles, for packaging, shipping, displaying, and dispensing. Some of these cartons are constructed of fiber or paperboard, which is a cost-effective material.
During the packaging operation, the containers either are formed into groups and inserted into a carton sleeve made from a blank, or the group is placed on the interior surface of the carton blank and the blank is folded around the group to form the carton. The exterior surface of the carton typically has graphics or logos printed thereon. Sometimes the group of cans or bottles is soaked with water as it is placed into the carton. This can result either from the washing step, filling step or can result from the contents of the container being cold, which causes moisture to condense on the outside of the container. Additionally, known paperboard carton blanks have been laminated on the exterior or outer surface, such as for protecting the ink-based graphics, adding additional graphic layers, adding additional strength or waterproofing the carton. During the packaging operation in which the containers are placed on top of the flat carton blank, the carton blank that supports the container group is conveyed across, for example, rollers, through a continuous motion article packaging machine. As this happens, the containers, for example cans, sometimes spin in place within the article group. This spinning tends to wear the uncoated interior surface of the carton blank. Since the cans also can be wet, the moisture invades or soaks into the paperboard blank from the interior surface, and wicks toward the exterior surface where the graphics printing is located. The presence of moisture in these areas causes degradation not only of the graphics, but also to the carton itself.
Additionally, when containers with residual water or moisture are enclosed within the carton, a humid atmosphere is created. This humidity generally moistens the paperboard where it contacts the cans. After the wet cans or containers contact the substrate or paperboard, moisture wicks through the paperboard fibers to the clay-coated, print surface. In this situation, the wet printed-clay surface contacts conveyor belts and static rails as the package moves through the manufacturing process, such as through a fill line. This contact causes stress at the exterior surface of the carton, with the stress being greatest adjacent to where the cans within the carton contact the interior surface of the carton. At the high stress points, the clay coating can separate from the paperboard fiber, usually in small areas or spots. These places where the clay and/or fibers are removed creates a defect termed “water-induced abrasion”, which is also termed “ink picking” since the abrasion removes the ink or printing from the surface of the blank, sleeve, or carton. Ink picking can also occur where the water forms a bubble or bulge at the surface of the ink or graphics. This bubble then comes in contact with the conveyor belt or a static surface during the packaging process to create the ink picking and mar the graphics. Besides creating the problem of ink picking, which damages the appearance of the carton, the humidity can also mold or otherwise corrode the cans in the carton. Without protection, the wetness of the cans can cause a substantial enough amount of wearing that the outside surface of the container becomes structurally damaged, exhibits “can chime” (bulging areas of a can outline macroscopically apparent on the exterior surface of the carton), and/or experiences ink picking.
This visual defect of water based abrasion or ink picking typically occurs where the bottom portion of the cans contact the packaging substrate or paperboard. Uncoated or unlaminated paperboard or clay covered kraft paperboard often abrades when the wet or moisture laden containers are enclosed within a formed carton. Generally, lamination or other coating reduces or controls the impact of any moisture from the containers that could limit the structural integrity of, or damage ink or printing on, the carton. Conventional carton designs will often have an entire surface, typically the exterior surface, of the paperboard carton laminated. However, laminating entire surfaces of the carton is expensive.
Also, if the entire interior surface of the carton is coated and the end flaps are sealed with wet cans enclosed therein, a humid condition is created inside the carton. This humid condition can cause mold to develop on the cans and can develop corrosion on their surfaces.
As an alternative to laminating an entire surface of the carton, only the interior surfaces of the carton in contact with the upper and lower portions of the containers could be laminated. However, while coating the contact surfaces of the interior of the carton could prevent impact abrasion and/or ink picking proximate the surface contacts of the containers, the moisture in the interior of the carton from the containers merely could leak to the sides of the carton to create structural weakening of the uncoated paperboard at the sides.
Accordingly, a need exists for an abrasion resistant coating that addresses successfully the foregoing problems and shortcomings of the prior art. It is to the provision of such a coating that the present disclosure is primarily directed. | {
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The invention relates generally to the field of input/output, or transceiver, circuits for use on integrated circuit chips to enable signals to be transmitted from, or received onto, an integrated circuit chip to and from external circuitry.
MOS circuits historically have had limited ability to sink current from, and source current into resistive loads, to drive very large capacitive loads at high speeds, and to afford high noise immunity. However, MOS circuits have improved in their switching speeds and recent short-channel MOS/VLSI technological advances have made even ECL-comparable performance possible in many applications.
As more and more functionality is integrated on-chip, the need for addressing the transient current behavior of MOS/VLSI chip interfaces becomes acute. In ECL designs, the peak current phenomena are dealt with by defining guidelines for packaging considerations (e.g. limiting pincount), but these specifications do not comprehend the high pincounts prevalent in MOS/VLSI designs today. The state-of-the-art in packaging is being sorely pressed by MOS circuit performance now.
The packaging affects the peak current characteristics of high performance MOS/VLSI parts because package pins have inductance. Voltage across an inductor is directly proportional to the inductance and to the rate of change of current through the inductor. Thus, as charge/discharge times decrease in larger capacitive loads, the time-compressed peak current transients can cause deleterious voltage rises at package pins, not to mention the phenomena created at the power/ground busses on-chip.
In new designs, several wires, each with a large capacitive load, are discharged through one ground pin. The need for current limiting is obvious in applications where worst-case speed specifications must be met at the slow corner of a process, even though the circuit may be as much as six times faster at the worst-case current corner of the same process.
In inherently noisy environments, such as a bus, the need for high noise immunity is great in order to guarantee data integrity. TTL technology has good noise characteristics, but MOS technology, with worst-case device threshold values less than 500 mV, is notoriously poor in applications where good low-state input voltage V.sub.il noise immunity is required.
A common way of compensating for deficiencies in MOS low-level noise immunity is by level-shifting, but a significant speed penalty may be exacted by the level-shifter stage. | {
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The present invention relates to an ostomy appliance comprising a body side member comprising an adhesive wafer or pad for securing the appliance to the user""s skin, said wafer or pad having a hole for receiving a stoma, and a separately exchangeable receiving bag secured to the body side ostomy member for receiving secretions from the ostomy, wherein the body side member comprises a first substantially annular first flange which is fixedly connected to the base plate and the receiving bag comprises a substantially annular second flange adapted for removable and adhesive coupling and sealing to said fist flange.
In connection with surgery for a number of diseases in the gastrointestinal tract a consequence is, in many cases, that the colon, the ileum or the urethra has been exposed surgically and the patient is left with an abdominal stoma and the effluents or waste products of the body, which are conveyed through these organs, are discharged through the artificial orifice or opening and are collected in a collection bag, which is usually adhered to the skin by means of an adhesive wafer or plate having an inlet opening for accommodating the stoma. Also in connection with a fistula, the patient will have to rely on an appliance to collect the bodily material emerging from such opening.
Ostomy appliances are well known. Such appliances may be two-piece or one-piece appliances. In both types of appliances, a body side member is attached to the wearer""s abdomen, and optionally a receiving member or bag is attached to the body side ostomy member for receiving exudates from the ostomy in case of a two-piece appliance.
When using one-piece appliances, the whole appliance, including the adhesive wafer or pad securing the appliance to the skin is removed and replaced by a fresh appliance. When using two-piece appliances, a body side ostomy member or carrier device is left in place for several days, and only the receiving member or bag is replaced.
The service time of the body side ostomy member depends on the amount and aggressiveness of the exudates and of the tightness between the ostomy and the body side ostomy member.
In a collecting system of this type known from EP patent application No. 0 276 043, a flange for adhesive connection with the flange of the collecting bag or with the bag itself being fastened on a base plate in the form of an adhesive pad.
In such a collecting system, the base plate of the carrier device must be able to remain on the user over a long period of time, for example up to 8-10 days. During this whole period of time, the carrier device must be capable of undergoing deformation owing to the user""s movements, washing, exposure to bag replacements, etc. Conventionally, the base plate of such a carrier device is designed as a thin adhesive foil, optionally with some sort of stiffening reinforcement disc for maintaining a plane adhesive surface for the bag. However, such a reinforcement disc prevents the base plate from following the contours of the body when the user moves, and it does not provide the desired shock absorbing effect between the collecting bag and the user, which, of course, reduces comfort. A less rigid disc would be able to follow the base plate during such movements, to be sure, but would thus exert a pull in it, which, in addition to transmitting an unpleasant pulling effect to the user""s skin, also weakens the adhesive effect between base plate and skin. Furthermore, the adhesive surface facing the bag will not in that case remain plane owing to the inevitable deformations, which results in problems of rearranging the bag on the user.
In the above EP patent application, an attempt has been made to eliminate these problems by connecting a rigid flange with the base plate via a flexible sheet, which, however, provides an unstable and insecure connection. Furthermore, the adhesive connection taught between bag and carrier device is provided either by a number of layers of adhesive applied to the flange of the base plate and activated one after the other, which reduces the number of times to which the base plate may be exposed to a change of bag to the number of layers of adhesive, or by using a new bag with a fresh layer of adhesive, which renders the system more expensive in use.
One solution to this problem is disclosed in the applicants own WO 96/38106 in which is disclosed an ostomy collecting system which comprises a collecting bag having an inlet opening formed in a bag wall and with surrounding connecting elements for connection with a stoma in a user, and a carrier device for the collecting bag. The carrier device comprises a base plate for fastening on the user and a substantially annular first flange connected to the base plate via a first connecting section. The connecting elements comprise a substantially annular second flange, which is fixedly connected to the collecting bag via a substantially annular second connecting section and is designed for removable and adhesive connection with said first flange. The first and the second flanges are connected with the base plate and the collecting bag, respectively, in such a manner that the outer radius of said second connecting section exceeds the outer radius of said first connecting section by a value which at least equals the total thickness of the first and the second flanges. The adhesive connection between the collecting bag and the carrier device is provided by a layer of adhesive applied on said second flange and capable of repeated adhesion with the first flange, and the first and the second flanges are made from a flexible and resilient material.
Although this design provides a connection between carrier device and collecting bag, which is stable against displacement forces, and which acts as a shock absorbing element there is still a need for a even more safe solution in which the connecting surface between the collecting bag and the body side member is maintained largely independently of the deformation of the body side member caused by, for example, the user""s movements, but which is nevertheless stable and continues to exhibit an even and flexible adhesive surface without wrinkles or gaps opening for passage of liquid between the flanges of the bag and the body side member. It is a further object that it should be possible to remove and reapply one or more bags repeatedly without any reduction in the life of the base plate and to reduce the necessary cleaning of the body side member when substituting the collecting bag.
The invention relates to a substantially annular flange for an ostomy collecting bag. The flange is divided in a radial direction into an inner portion and an outer portion by at least one opening therethrough in a substantially circular zone.
Furthermore, the invention relates to an ostomy collecting bag having a substantially annular flange connected thereto by a substantially annular connecting section. The annular flange is designed for removable and adhesive connection with a second flange connected with a body side member of an ostomy appliance by a second connecting section. The annular flange has at least one opening therethrough so as to divide the annular flange into an inner portion and an outer portion in a radial direction.
Still further, the invention relates to an ostomy appliance having a body side member with an adhesive wafer for securing the appliance to a user""s skin, the wafer having a hole for receiving a stoma, and a separately exchangeable collecting bag. A substantially annular first flange is connected to the body side member via a first connecting section, and a substantially annular second flange is connected to the collecting bag via a second connecting section for adhesive connection with the first flange. The second flange has at least one opening therethrough that divides the second flange into an inner portion and an outer portion in a radial direction. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
This invention relates to polyurethane elastomers and is more particularly concerned with hydrolytically stable polyester polyurethane elastomers.
2. Description of the Prior Art
The preparation of thermoplastic polyurethane elastomers from polyester polyols is well known in the art. Such elastomers can be extruded, injection molded, cast and fabricated in other known manner. Generally speaking, such polyester based polyurethane elastomers are recognized for their greater resistance to high temperatures as compared to their polyether polyol based counterparts. However, the latter polyether based polyurethanes enjoy a recognized advantage in hydrolytic stability over the polyester materials.
Hydrolytic instability of polyester polyurethanes, or, their loss in physical properties when exposed to hydrolyzing conditions such as the combination of high temperature and humidity, has long been recognized in the art. Also receiving long recognition has been the concept of relying on carbodiimide containing additives both reactive and non-reactive types to impart enhanced hydrolytic stability to various polymer systems including, particularly, polyester polyurethanes. Presumably, the carbodiimide additives function in the polymer by virtue of the quick reaction of the carbodiimide linkage with a water molecule to form a urea thereby preventing polymer molecular weight reduction which would otherwise occur via scission of polymer links by aqueous hydrolysis of the ester functions.
Typical of the prior art methods for stabilizing polyester polyurethane elastomers is the use of Isonate.RTM. 143L as the diisocyanate in the preparation of one-shot elastomers which are not thermoplastic. The 143L liquid diisocyanate is a proprietary product which contains; carbodiimide linkages which, in turn, impart the hydrolytic stability to the final polymer; see Upjohn Tech. Bull. 402, June 1, 1969 entitled "The Use of Isonate.RTM. 143L in Urethane Elastomers". It should be noted that the polyester polyurethanes obtained are not thermoplastic.
Further, it is known to employ carbodiimide containing isocyanates in the preparation of cast polyester polyurethanes; see U.S. Pat. No. 4,088,665, example 17.
U.S. Pat. No. 3,193,522 teaches the stabilization of vulcanized or cross-linked polyesters and polyester urethanes through the addition of polycarbodiimide additives having more than 3 carbodiimide groups in the polycarbodiimide chain, and, optionally, the presence of isocyanate groups also in the polycarbodiimide chain which would allow the chemical incorporation of the polycarbodiimide into the polyester urethane.
U.S. Pat. No. 3,226,368 discloses the preparation of polyester polyurethanes wherein excess isocyanate over and above that required to react with the polyester polyol is concomitantly reacted in the presence of a carbodiimide forming catalyst to form a large number of carbodiimide groups in the polyurethane chain. However, this method of production is not suitable when a fast type of polymerization process is required, typically, when the polyurethane is being prepared in a screw extruder or the like. The gas evolving carbodiimide formation would create bubbles or voids in the polymer as it was being extruded. In fact, this particular reference at column 1 beginning at line 24 seeks to avoid accelerated reactions and specifically calls for a slow reacting system which would be suitable for casting techniques where prolonged pot life is required.
We have now discovered how to prepare thermoplastic polyester polyurethanes which are characterized by a high degree of hydrolytic stability when tested under rather severe conditions of humid aging.
Further, because the carbodiimide entity which imparts hydrolytic stability is polymerized into the polyurethane chain it cannot be solvent leached or extracted from the polymer. Contrastingly, the majority of the prior art methods providing for enhancement of hydrolytic stability of polyester polyurethanes are not leach resistant (see the comparison of sample 4 versus samples 7 and 8 set forth in Example 2 below).
Surprisingly, the physical properties of the polyester polyurethanes of the present invention, particularly tensile strengths and elongations, are superior to prior art polyester polyurethanes having large amounts of polycarbodiimide prepared in situ during polyurethane formation or those having additive carbodiimides (see U.S. Pat. Nos. 3,226,368 and 3,193,522 cited supra) to achieve solvent resistant hydrolytic stability.
Most surprising, however, is the fact that the present thermoplastic polyester polyurethanes have all of the above features combined with the fact that the polymers are completely clear with transparent clarity. The combination of all of these properties, i.e. thermoplasticity, hydrolytic stability, solvent resistance, superior tensile strength and elongation, and very good polymer clarity, has not hitherto been found in one thermoplastic polyester polyurethane to our knowledge. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The invention relates to a manhole cover that is particularly simple and inexpensive to manufacture.
2. Discussion of the Prior Art
GB 2 145 444 A, the closest prior art, discloses a manhole cover that comprises only the two components of a base and a filling. The preferred material for the base of the manhole cover is the same material that is used for a manhole that is to be covered by the manhole cover, whereby, high-density polyethylene is named as an example. The manhole serves as access to the sewage system for inspection purposes. The disclosure does not mention how the manhole cover is arranged and what loads it can withstand.
An unconventional manhole cover is disclosed in DE 298 01 640 U1. This manhole cover has a metal outer shell on its bottom side, into which the actual base, which has a certain layer thickness, is then cast, whereby the filling is then cast into the base. The production of this manhole cover, which overall comprises a three-layer construction, is therefore technically complicated. The components or materials used are relatively expensive. Thus, for example, the outer shell is provided as a break-mold made of metal, and the base is constructed either of cast steel or of polymer concrete, the polymer concrete having thicker dimensions. The filling is also made of polymer concrete. The manhole cover is to be arranged in a track system and is constructed to withstand foreseeable high stresses caused by a high volume of traffic, high mechanical stresses, and aggressive climatic conditions.
U.S. Pat. No. 5,123,776 discloses a manhole cover that is constructed as a filled-in hollow body. A sheath surrounds the filling on all sides, so that the filling must be introduced into the sheath through a filler opening. The sheath is preferably made of polyethylene, and the filling preferably of concrete. Handles for lifting purposes are basically constructed as U-shaped brackets that open downward. They can be pulled up out of the manhole cover in a vertical direction, so that they can be gripped in order to raise the manhole cover. When in their lowered non-operational state, the lifting handles each rest in a recess that is provided in the surface of the manhole cover. The production of the manhole cover is complicated, because a hollow body must be filled, whereby providing the openings in the hollow body necessary for the vertical mobility of the lifting handles complicates the filling process. or, if the openings are not formed in the filling process, after the filling has hardened, several through-bores have to be made in the manhole cover to create channels through which the lifting handles can extend.
U.S. Pat. No. 4,974,992 discloses a cover that is not used as a manhole cover, but rather, is constructed as a metal plate and serves to cover trenches in street surfaces. The cover is used when digging work is suspended and traffic is allowed on the street surface. In order to withstand the traffic loads, the metal plates have appropriately sturdy dimensions and are consequently heavy. In order to simplify their handling, Omega-shaped handles that are rotatable on both ends are provided in the cover plate and can be swiveled from their downward-hanging resting position into an upright operational position in which they project upwards above the surface of the cover.
U.S. Pat. No. 4,801,483 discloses a cover that has a core with a cell structure, as well as an external, closed sheath layer made of a fiber-reinforced resin. The cover is to specifically sustain high dynamic loads, so that, e.g., the vehicles in road traffic can drive over the cover. The core can, e.g., be constructed of multiple balsa wood blocks, and the sheath layer of fiberglass-reinforced epoxy or polyester resin. The manufacture of the cover is complicated, because two separate parts of the sheath layer are produced. A first part of the sheath layer forms a recess into which the individual components of the core are inserted. The core is then covered with the second part of the sheath layer. One must ensure that both parts of the sheath layer are connected to each other at all contact points they share with one another and with the core structure, and that all air bubbles be avoided during this process, in order to create an essentially monolithic mass. Aids for lifting the cover are not provided; rather, the cover has armature bores that allow ground anchors to be inserted, so that the cover can be affixed to the substrate with the aid of these ground anchors.
In numerous instances, manhole covers are necessary in places other than streets. For example, inspection and maintenance manholes may be provided on private properties, e.g., in garage entrances, in order to provide access to the building's sewage system installations for cleaning and inspection purposes. Mechanical stress caused by heavy trucks is unlikely here, as is heavy traffic or high exposure to de-icing salt in the winter. Conventional manhole covers are therefore frequently overqualified for these applications and, due to their complicated production process or the costly materials used. are unnecessarily expensive.
The object of the invention is to improve a generic manhole cover in such a way that it can be produced as inexpensively as possible. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The present invention relates to a media contents distribution system, and more particularly to a system for distributing a multimedia content containing video data and/or audio data to users, while preventing unauthorized use thereof.
2. Description of the Background Art
In recent years, network systems have been developed as part of the social infrastructure, and consequently, multimedia contents containing digital data such as images, moving pictures, and audio are widely spread via such networks. Moreover, large-capacity recording media have been developed, making it possible to distribute multimedia contents via such recording media. Digital data is easy to preserve and duplicate, and does not deteriorate in quality through preservation or duplication. As a result, if unauthorized preservation or duplication of media contents containing digital data is committed by a recipient, the rights of the author of such media contents are infringed, thus detracting from the profit of the provider of the media contents. In order to prevent this situation, when distributing any media content containing digital data, it is necessary to impose certain limitations on the use of the media content by users.
Conventionally, the limitation on the use of media contents has been realized by, for example, encrypting digital data. Another alternative has been to ensure that a user makes an agreement concerning the use of a media content at the time of purchasing the media content, after which the limitation on the use of the media content is left up to the conscience of the user.
However, even if digital data is encrypted, a decryption key for decrypting the encrypted digital data may be stolen, so that it is still impossible to completely prevent unauthorized preservation or duplication of media contents by the recipients. Any agreement directed to the limitation of the use of a media content cannot guarantee that the agreement will be abided by.
A multimedia content is characterized in that, once purchased, it can be played back or viewed an unlimited number of times, substantially perpetually. On the other hand, from the perspective of the user, some media contents are only needed for a certain period of time and never again thereafter. In particular, as the amount of a single media content increases, which is currently the case, the data which is really needed by a user may often be only a part of the purchased media content. Even in such cases, however, the user is still paying a fee which often far exceeds what should be the real price in view of the extent to which the user has actually used the media content.
Therefore, from the perspective of the provider of a media content, a system is desired which can effectively limit the use of a media content by a user; and from the perspective of the user, a system is desired which only requires the user to pay a price according to the extent to which the user has actually used the media content, in exchange for somewhat limited usage. There have not been known any such systems to date. | {
"pile_set_name": "USPTO Backgrounds"
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The invention relates generally to the field of geological formation evaluation and, more particularly, to a method for evaluating a geological formation which integrates well data and high resolution computed tomography of rock samples thereof. A system for performing the method also is provided.
Well log measurements can provide a number of rock properties needed to plan well completion and lateral placement. These properties include mineralogy, bulk density, porosity, electrical resistivity and elastic-wave velocities. Elastic-wave velocities and bulk density can be used to compute the elastic moduli needed to estimate the mechanical properties and strength of the formation. These mechanical properties are important for planning deviated and lateral wells and for fracture treatment. However, conventional well data resolution typically is only about 1.5 to 1.0 feet (about 46 cm to about 30 cm). This well data resolution typically is not high enough for evaluating some formations, such as thinly laminated formations which have thicknesses below the indicated level of resolution feasible with conventional well data.
Shale is an unconventional source of oil and/or gas. Shale rocks have not been studied extensively due to the fact that they traditionally were thought of as the source rock and not a potential reservoir because of their low porosity and permeability values. However, there are new methods to extract the oil and gas within these rocks, and therefore, there is great interest in analysis methods to characterize these rocks to better understand the mechanics of production from shales. Well data resolution alone typically is not high enough for evaluating thinly laminated formations of shale. The scale of lamination of shale can be measured in the cm or mm range significantly less than 1 foot (30 cm). Traditionally, there were only limited ways to analyze shale samples, and this began with scanning electron microscopes (SEM). The SEM image provides a two-dimensional (2D) picture or image of the sample that typically has a resolution of approximately 15-100 nanometers. Using only two-dimensional images, however, one is only able to estimate porosity and organic content. 3D CT imaging and/or FIB-SEM (focused ion beam combined with SEM) imaging have been proposed for evaluating some properties of shale, such as identification of the components, including the mineral phases, organic-filled pores, and free-gas inclusions; and computations of TOC (Total Organic Content), porosity, pore connectivity, and permeability in the three axis. Sisk et al, SPE 134582, “3D Visualization and Classification of Pore Structure and Pore Filling in Gas Shales”, 2010; Curtis et al, SPE 137693, “Structural Characterization of Gas Shales on the Micro- and nano-Scales”, 2010; Milner et al, SPE 138975, “Imaging Texture and Porosity in Mudstones and Shales: Comparison of Secondary and Ion-Milled Backscatter SEM methods”, 2010. However, this digital rock physics technology, e.g., 3D CT imaging and/or FIB-SEM technology, does not directly provide the elastic properties needed for computing the elastic moduli and other mechanical properties of the formation.
There remains a need for methods and systems to provide evaluations of geological formations that can combine well data with higher resolution digital rock physics in determining formation properties such as elastic properties or other mechanical properties thereof. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The field of the present invention is deformable mirrors.
2. Background
Deformable mirrors are mirrors whose reflective surfaces can be deformed in a manner that allows for control of the wavefront of the reflected light. The need for deformable mirrors arises in adaptive optics for wavefront control and correction of optical aberrations. Deformable mirrors are often used in combination with wavefront sensors in real-time control systems. In such systems, the wavefront sensor communicates the measured wavefront to a computer which determines how the deformable mirror surface should be shaped in order to achieve the desired wavefront. Mechanical or acoustic actuators control the surface shape of the deformable mirror and receive commands from a controller coupled to the computer to shape the surface of the deformable mirror accordingly.
There are two main types of deformable mirrors, continuous faceplate and segmented. Continuous faceplate deformable mirrors have discrete actuators coupled to the back surface of a thin deformable faceplate, and the actuators largely control the surface shape of the faceplate. The overall surface shape of the plate depends on the combination of forces applied to the faceplate, including forces from individual actuators, combinations of actuators, boundary conditions, and the geometry and the material of the plate. Continuous faceplate mirrors are generally preferred over segmented deformable mirrors, since the former allow smooth wavefront control with very large-up to several thousands-degrees of freedom.
Segmented deformable mirrors are formed by independent mirror segments. Each segment may be moved up or down freely with no inter-segment coupling. This type of movement results in a discontinuous surface that is a stepwise approximation of the desired wavefront, and such surfaces work poorly for smooth, continuous wavefronts. Sharp edges of the segments and gaps between the segments contribute to light scattering and heating between the segments. Both of these undesirable effects are amplified when a segmented deformable mirror is used with higher power light sources, thus limiting the applications for such mirrors.
The deformable mirrors commonly used in conjunction with high energy laser (HEL) systems are of the continuous variety. HEL systems generally involve the use of a laser or other source of a high-power directed electromagnetic energy for any one of a number of purposes. During use, the laser heats and can create distortions within the optical system. While a deformable mirror is designed to correct the internal optical distortions, it too is heated and distorted in ways it cannot correct, leading to degradations in HEL performance.
Current high energy level deformable mirrors have a fairly common architecture, consisting of actuators, which are often piezo-stacks, mounted on a base plate and attached to a thin facesheet through metal flexures. Each actuator is adjusted in piston to create an overall deformation of the facesheet, which in turn alters the wavefront of the reflected HEL beam. With this arrangement, the thin facesheet minimizes the bending stiffness of the mirror in response to the pistoning actuators. One shortcoming of this type of deformable mirror design is that it is subject to significant thermal deformation, which causes, optical distortions, when used with high powered lasers or with lasers of lesser power for extended periods of time. The thermal deformation arises because the thin facesheet is heated by the laser and heats up tremendously as compared to the actuators and base plate, resulting in a differential in thermal expansion which twists the flexure attachments to the actuators, thereby causing ripples in the surface of the facesheet. Also, the facesheet and each of the flexure attachments can have a local mismatch in thermal expansion, thereby causing a local curvature above each actuator and a dimple effect across the surface of the facesheet.
With continuous deformable mirrors, there are two potential approaches for reducing optical distortions caused by thermal deformation of the facesheet. One option is to use a thicker facesheet. However, use of a thicker facesheet reduces the flexibility of the deformable mirror surface, and hence reduces the wavefront correction capability. Another option is to use a segmented mirror. However, as discussed above, segmented mirrors have their own shortcomings when used with an HEL beam. | {
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This invention relates generally to semiconductor devices and manufacturing methods and more particularly to field effect semiconductor devices and manufacturing methods.
As is known in the art, metal gate and junction gate field effect transistors, sometimes referred to as MESFET and JFET devices, have been formed on high resistivity silicon, gallium arsenide, or silicon on sapphire substrates. In order to achieve efficient operation at microwave frequencies in excess of 1 GHz the gate length should be 1 micrometer or less, the gate capacitance should be small, the depth of the conducting channel should be substantially smaller than the length of the gate in order to avoid increasing the effective conductive channel length of the device because of fringing fields, the conductive channel doping should be relatively high, (e.g., N=10.sup.17 atoms/cm.sup.3), the carrier mobility in the conductive channel region should be high to achieve a low on-resistance of the device, the source-drain spacing should be small (e.g. less or equal to 3 micrometers), the contact impedance should be small, and the gate leakage current should be small in order to avoid excessive loading of a drive circuit.
While the requirement of a very shallow conductive channel depth of 0.2 to 0.3 micrometers may be met using gallium arsenide material by forming an appropriately doped, shallow epitaxial layer on an insulating gallium arsenide substrate, and using silicon by an epitaxial or ion implanted layer on a highly resistive single crystal silicon substrate, meeting such shallow channel depth requirement is difficult where the epitaxial layer is of one material, such as silicon, and the substrate is of a different material such as sapphire. That is, complications arise in forming very shallow conductive channel depths for MESFET or JFET devices using silicon on sapphire substrates because of the fact that the electrical properties of the silicon film on the sapphire substrate are generally poor at and near the silicon-sapphire interface. Consequently, while silicon on sapphire devices are theoretically highly desirable since they have greatly reduced parasitic capacitances and readily lend themselves to the fabrication of microwave monolithic integrated circuits, when such devices utilize the full thickness of the silicon the minimum thickness of the silicon, and hence the minimum thickness of the channel depth, is typically 6000 .ANG. and therefore the depth of such conductive channel is only slightly shorter than the gate length. However, if the conductive channel depth is only slightly shorter than the gate length fringing fields spread, increase the effective gate length of the device, and thereby reduce the operating frequency bandwidth of the device.
As is also known in the art, devices of the type described above are generally made by positioning a gate, 1 micrometer or less in width, with a very high degree of masking accuracy precisely between the source and drain regions, which are typically spaced 3 micrometers apart. This is a particularly difficult task, especially if the device is shaped so that registration in two dimensions must be achieved, e.g. in an interdigitated structure. Such technique is usually a so-called "lift-off" technique where a layer of photoresist is deposited on the surface of the semiconductor and patterned to expose the gate of the semiconductor region. Metal is then deposited over the photoresist and onto the exposed gate region. The photoresist with metal on its surface is then lifted off to leave the metal gate on the semiconductor. Such technique may be useful in some applications. However in those applications where it is desired to form a Schottky contact using a platinum deposition and a high temperature process to form platinum-silicide prior to deposition of an aluminum metal gate contact, the photoresist is not generally capable of withstanding such high temperature process thereby limiting the use of this "lift-off" technique. | {
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This invention relates to an apparatus for charging flat coiler cans (that is, coiler cans which have an elongated horizontal cross-sectional configuration) with sliver at a sliver producing fiber processing machine, such as a drafting frame or a carding machine. The sliver, which may be composed of cotton fibers, chemical fibers or the like, is discharged by a stationary, rotating coiler head and is deposited in coils into the can which stands on a support such as plate, sled, carriage, conveyor belt portion (emplacement) or the like (hereafter generally referred to as "sled") and executes a back-and-forth motion in its horizontal length dimension by virtue of reciprocating the support by a drive mechanism.
German Auslegeschrift (application published after examination) 11 07 566 discloses an apparatus in which the can is standing on a sled in the sliver charging station. The reciprocation of the sled is effected by means of a bidirectionally rotatable threaded spindle on which there is mounted a travelling nut affixed to the sled. The spindle is driven by a rotating component of the coiler head drive. The sled is, together with the can, reciprocated as long as necessary to ensure that the can is filled with the sliver coils. At the end of the reciprocating path the travelling direction of the sled is automatically reversed. It is a disadvantage of this arrangement that driving the sled by a spindle assembly is complex and expensive. It is a further drawback that the back-and-forth motion of the sled is too slow, particularly in current high-output drafting frames which discharge sliver at a speed of 1,000 m/min and above. | {
"pile_set_name": "USPTO Backgrounds"
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In rotary electric motors for a vehicle, a full-wave rectification system using diodes as rectifying elements is generally known. For higher efficiency, a rectification system using switching elements as the rectifying elements so as to reduce a loss generated due to the rectifying elements is increasingly used.
There has already been proposed a power converter for a vehicle, which is configured to use the switching elements as the rectifying elements and obtain an estimated angular position at which the diodes are turned ON and OFF through a phase-locked loop circuit so as to control ON and OFF of the switching elements based on the estimated angular position without mounting a rotational position detecting sensor (see, for example, Patent Literature 1). | {
"pile_set_name": "USPTO Backgrounds"
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Multiple-loop refrigeration systems are widely used for the liquefaction of gases at low temperatures. In the liquefaction of natural gas, for example, two or three closed-loop refrigeration systems may be integrated to provide refrigeration in successively lower temperature ranges to cool and liquefy the feed gas. Typically, at least one of these closed-loop refrigeration systems uses a multi-component or mixed refrigerant which provides refrigeration in a selected temperature range as the liquid mixed refrigerant vaporizes and cools the feed gas by indirect heat transfer. Systems using two mixed refrigerant systems are well-known; in some applications, a third refrigerant system using a pure component refrigerant such as propane provides initial cooling of the feed gas. This third refrigerant system also may be used to provide a portion of the cooling to condense one or both of the mixed refrigerants after compression. Refrigeration in the lowest temperature range may be provided by a gas expander loop that is integrated with a mixed refrigerant loop operating in a higher temperature range.
In a typical multi-loop mixed refrigerant process for liquefying natural gas, the low level or coldest refrigeration loop provides refrigeration by vaporization in a temperature range of −30 to −165° C. to provide final liquefaction and optional subcooling of cooled feed gas. The refrigerant is completely vaporized in the coldest temperature range and may be returned directly to the refrigerant compressor, for example, as described in representative U.S. Pat. Nos. 6,119,479 and 6,253,574 B1. Alternatively, the completely vaporized refrigerant may warmed before compression to provide precooling of the feed gas as described in U.S. Pat. Nos. 4,274,849 and 4,755,200 or for cooling of refrigerant streams as described in Australian Patent AU-A-43943/85. A common characteristic feature of these typical liquefaction processes is that the refrigerant in the low level or coldest refrigeration loop is completely vaporized while providing refrigeration in the lowest temperature range. Any additional refrigeration provided by the refrigerant prior to compression thus is effected by the transfer of sensible heat from the vaporized refrigerant to other process streams.
In known liquefaction processes that use three integrated closed-loop refrigeration systems, the size of the process equipment in the third or lowest temperature refrigeration system may be smaller relative to the two warmer refrigeration systems. As the process liquefaction capacity is increased, the sizes of the compression and heat exchange equipment in the two warmer systems will reach the maximum sizes available from equipment vendors, while the sizes of the corresponding equipment in the lowest temperature refrigeration system will be smaller than the maximum sizes. In order to further increase the production capacity of this liquefaction process, parallel trains would be needed because of compression and/or heat exchanger size limitations in the two warmer refrigeration systems. It would be desirable to increase the maximum production capacity of this liquefaction process at the limits of available compressor and heat exchanger sizes, thereby allowing the use of larger single-train liquefaction processes. | {
"pile_set_name": "USPTO Backgrounds"
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Businesses often have their own software platforms for storing, accessing, and manipulating data, such as customer data. If a business acquires another business or otherwise acquires a large amount of data that needs to be migrated into the platform, the process of migrating the data may render the underlying data that is being migrated unable to be accessed or modified during the migration period. In many cases, the migration period may be lengthy. For example, it may not be uncommon for such a data migration to take as long as 48 to 72 hours. This poses a problem for organizations that need to access and modify that data during the migration period. For example, a financial service provider that maintains a large volume of customer financial account information may receive calls or other inquiries from customers wanting to modify their information by, for example, updating their phone number or address. In addition to data migration processes, data may also be inaccessible during system upgrade downtime, system outages, or system maintenance.
To address this problem, one approach is to have customer service representatives field these requests during the migration period, write down each requested modification to customer data on a form, and then manually update each record after the data migration has been completed based on the forms. However, this approach is very labor intensive process and poses a risk of human error in recording or updating the customer data modifications.
Accordingly, there is a need for improved systems and methods to provide customer data access that allow a customer service representative to access, view, and modify customer information during a data migration process. Embodiments of the present disclosure are directed to this and other considerations. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
The present invention relates to adsorbents made from active metals dispersed on inert porous supports, such as alumina, silica aluminosilicates, zeolites, clay and the like effective for removing low level elemental mercury from hydrocarbons.
2. Discussion of Background and Material Information
The present invention is based on the discovery that elemental mercury in naphtha can pass through a steam cracker somewhat unscathed and can attack the aluminum bundles of a down-stream cold box resulting in the failure thereof. In addition to the economics associated with the failure of the cold box, a collapse of the cold box would also pose environmental problems.
Various attempts have been made in the prior art to remove mercury contaminants from hydrocarbon streams. For example, it is known that elemental mercury can be removed from a hydrocarbon stream using a packed bed of metal particles, such as copper, silver, aluminum and zinc. In so doing, the mercury forms an amalgam with the active metals and remains on the particle surface.
The previous attempts to remove mercury, however, have not been found to be successful in preventing elemental mercury in naphtha from passing through the steam cracker. First, the particles of metal are not porous so that only the outer surface is available for a mercury reaction and adsorption. Consequently, the column size and amount of metal required to treat high volumes of naphtha are somewhat impractical. Second, the outer surface of the active metals, such as aluminum, copper, and zinc is typically covered with a layer of metal oxides. Thus, an acid-wash pre-treatment is normally needed to remove the oxide layer and activate the metal particles before use for this purpose. The latter treatment, however, imposes extra difficulties on safety, operations, and waste disposal. For the sulfide approach, its operations include precipitation, filtering and handling of a wet filter cake which are inefficient.
U.S. Pat. No. 4,417,626, DOMTAR Inc., discloses the use of sodium sulfide to remove mercury from wastewater.
J.P. 62-68,584, KOKAI Tokyo Koho, uses arsenic sulfite to remove mercury from wastewater.
U.S. Pat. No. 3,704,875, PENNWALT Corp., discusses the use of active metal particles, including zinc and aluminum, to remove mercury from aqueous streams such as wastewater and other industrial wash effluents.
U.S. Pat. No. 3,883,426, ETUDES ET PROCEDES d'ASSAINISSEMENT PURATOR, also discusses the use of active metal particles including zinc and aluminum to remove mercury from aqueous streams, such as wastewater and other industrial wash effluents.
Sulfides, such as sodium sulfide, have also been proposed to precipitate the mercury from the hydrocarbon liquid.
Related to the foregoing, other techniques have been proposed for the removal of mercury from liquids and gases. An example of technology of mercury removal from liquids and gases is outlined in the Encyclopedia of Chemical Technology, 3d Edition, Vol. 15, pp. 168-169 (1981).
It has also been proposed to adsorb mercury on high surface area substrates, such as activated carbon.
French Patent No. 2,310,795, INSTITUTE FRANCAIS DU PETROLE, discloses the removal of mercury from gases and liquids using an adsorbent mass of metal on a ceramic support. The method disclosed involves contacting the gas or liquid with an adsorbent mass containing a) SiO.sub.2, Al.sub.2 O.sub.3 silica-alumina, a silicate, and aluminate or an aluminosilicates support, and b) one or more metals which form alloys with mercury. The adsorbent mass is disclosed as having a specific surface area of greater than 40 m.sup.2 /g, i.e. 40-250 m.sup.2 /g, and the metal in the mass is present as crystallites having an average diameter of less than about 400 Angstroms, and preferably less than 100 Angstroms. The support is disclosed as preferably being Al.sub.2 O.sub.3 and the preferred metal is Ag or a mixture Ag with Au, Ni or Cu. The adsorption mass may also contain ThO.sub.2 or MgO. It is disclosed that the activation of the adsorption mass and/or its regeneration are effected by heating in the presence of a like hydrocarbon and optionally steam. The support is disclosed as preferably being in the form of 1-10 mm diameter balls, such as extrudates or pellets. Optionally, the support may be mixed with the active phase and then formed into pellets. The adsorbent metal is used in amounts of 200 ppm--20%, and more preferably 0.05-1% for Au and 0.1-5% for Ag or Cu. It is disclosed, however, that other metals may be present in amounts within the range of 0-20% and preferably 0.01-10%. It is also disclosed that regeneration is effected by heating at 200.degree.-500.degree. C., and preferably 320.degree.-420.degree. C. in a current of inert or reducing gas.
NL 7613-998, Institute Francais Du Petrole, discloses the use of dispersed sulfided metal on an inorganic carrier to remove mercury from gases or liquids by contacting the fluid with a fixed bed of an adsorbent comprising Cu sulfide on SiO.sub.2, Al.sub.2 O.sub.3, SiO.sub.2 --Al.sub.2 O.sub.3, silicate, aluminate or alumina silicate support in the treatment of natural gas, liquified natural gas, and electrolytically produced H.sub.2.
SU 633,565, KAZEA UNIVERSITY, is directed to the removal of mercury from industrial air by using a silica gel adsorbent containing silver oxide. The adsorbent is disclosed as being prepared by impregnating silica gel with silver nitrate and calcining.
JP 52-105,578, MITSUI MINING & SME, is directed to the removal trace mercury from exhaust gases by adsorption in columns packed with noble metal-supporting, nonmetallic fibers, e.g. of quartz.
DE 3,026,430, NIPPON KOKAN K.K., discloses the removal of resolved heavy metals from liquids by adsorption of metals on steelwork slag, which is disclosed as being particularly suitable for removing mercury and the like, from waste water.
JP 53-73,859 discloses the use of ferrous salts on activated carbon for the removal of mercury ions from effluent.
JP 49-74,195, SUMITOMO CHEMICAL CO., LTD., discloses the use of an activated carbon impregnated with copper for mercury removal from gas.
The following patents relate to mercury removal over activated carbons.
U.S. Pat. No. 3,755,989, UNION CARBIDE CORPORATION, is directed to mercury removal from a gas stream by feeding the stream to a carbon adsorbent bed.
French Patent No. 2 206 843, SHOWA DENKO K.K., is directed to removal of mercury from gases by adsorption on active carbon treated with sulfuric acid.
JP 5 2053-793, SUMITOMO METAL MINI K.K., is directed to the removal of trace mercury from sulfuric acid by conversion to bromide or iodide followed by adsorption on activated carbon.
DL 107-890, BEILING H., is directed to removing mercury from effluent waters by adsorption on active carbon and ion exchange resin and elusion.
SU 640-750, FEDOROVSKAYA L. F., is directed to removal of mercury from industrial waste gas by adsorption on activated carbon in the presence of chlorine for high adsorption capacity.
DE 160-802-A, CHEM WERK BUNA VEB, is directed to mercury removal from gas by adsorption on sulfur-containing active carbon.
SU 1161-157-A, SECONDARY RESOURCES, is directed to the removal of mercury vapor from gases by adsorption on activated charcoal treated with vinyl chloride oligomers.
However, removal of mercury contaminants from the hydrocarbon stream is a problem which has been solved by the present invention, as described in more detail hereinafter, in a manner which is believed to be novel and unobvious relative to what has been taught by the prior art. | {
"pile_set_name": "USPTO Backgrounds"
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The present invention relates to the exploration and production of petroleum from earth formations, and more particularly, to methods for determining the amount of and properties of fluids present in such a formation.
In the petroleum industry, one of the most valuable and informative techniques for determining the characteristics of an earth formation located well below the surface, and the nature of the fluids which it may contain, is to remove and bring a portion of the formation and/or its fluids to the surface for analysis. This is done most commonly by "coring" the formation. This coring may be accomplished by conventional coring, pressure coring or sponge coring, when it is desired to recover a substantial portion of a formation or formations. However, sidewall plugs or cores are also employed, when only a small portion of the earth formation is desired or when more economical samples are desired.
It is often important to type the hydrocarbon crude in order to be able to determine the ease of removal of the crude oil. A reliable method for estimating key hydrocarbon properties, such as API gravity, or viscosity from sidewall samples could preclude the need for expensive production testing. The potential economics through reduced costs and/or reduced risks to a well could be substantial. Further, variations in hydrocarbon properties within or between reservoirs could be more easily determined with increased sample density at lower cost.
The importance of coring in the production of petroleum has recently been increasing as more and more secondary and tertiary recovery is being made of petroleum reserves. In a formation undergoing primary production, the original reservoir fluids are little altered from their condition for the last several thousand or more years. They may migrate as the oil is produced, but their properties are not changed significantly. However, when fluids and/or other compounds are injected into a formation to stimulate its production, the nature of the connate fluids is accordingly altered, sometimes to a very substantial extent. When this occurs, the more traditional well-logging tools may be unable to provide any useful information about the formation and/or its fluids. In all too many instances, the only way to determine how much oil is left, and thus whether it can be produced economically, is to physically recover a portion of the formation by taking a core sample.
It will therefore be appreciated that the analysis of the amount and properties (viscosity, API gravity, etc.) of the oil in a core sample can be critically important. The viscosity (which is correlated to API gravity) of the crude in a formation often determines whether the oil in the formation may be commercially produced. Similarly, the final true residual oil saturation of a formation is a determination that can make or break a multi-million dollar enhanced recovery project.
Typically, oil is extracted from a portion of a core by means of a soxhlet extractor. Other techniques are also available such as the Dean-Stark extraction technique. However, typically these prior art techniques use a hot solvent which dissolves the oil and boils off the water that is found in the core sample. This is usually the result of using a solvent that is capable of dissolving only the oil and not the water. At the end of the extraction, the oil recovered remains in the solvent and is usually discarded. The soxhlet technique only cleans the sample. In Dean-Stark analysis, the condenser is placed to the side of the extraction vessel's center line and any water that is boiled off is condensed and collected in a side arm under the condenser; the (generally lighter) solvent then floats on top of the collected water and overflows the sidearm to drip back onto the sample. In Dean-Stark analysis the volume of oil is inferred by subtracting the amount of water boiled out of the rock from the total pore volume of the rock. If there was any gas in the original core, the calculated oil volume will be too high. That is, the prior art techniques can not extract and separately recover both the oil and water.
These and other limitations and disadvantages are overcome by the present invention, however, and methods are provided for determining the amount of fluids in a porous sample, and the petrophysical properties of those fluids. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The present invention relates to bracket supports of the type that are commonly employed in certain wall structures, such as partitions that include a plurality of spaced vertical studs defining the wall frame. More particularly, the invention herein pertains to a substantially integral support that offers significant economic advantages over conventional structures.
2. Description of the Prior Art
An often-utilized wall construction that is particularly favored by retail business establishments and offices includes a frame formed by a plurality of spaced, vertically arranged wall studs. Often such studs are metallic and generally U-shaped in cross section, opposed flanges providing strength and anchor points for the wallboard panel surfaces of the partition-type wall units. Construction of this type is almost universally employed at the present time in the division of office space into tenants' preferred anrrangements as it is both economical and semipermanent, allowing easy rearrangement for new occupants.
Commonly, shelf space adjacent the partition is desired. Thus, a series of wall shelves will be provided, each shelf positioned at a right angle to the wallboard surface. These shelves are usually supported by brackets that protrude from and are anchored in some manner within the partition.
A number of arrangements have been provided in the past for properly mounting such brackets securely. The bracket support must provide adequate resistance to the weight and bending moments that are transferred to it in consequence of the loading of the cantilevered wall shelves. Further, the geometry of such support must be fully compatible with the wall unit and studs.
A common bracket supporting mechanism generally includes an elongated, often slotted, core member of bar steel or the like. The slots in this member are intended to engage a mating tongue that projects inwardly at the inner end of the conventional wall bracket. A critical feature of the overall bracket support pertains to the mode of securing the slotted support bar to the wall. Such apparatus, often an elongated housing, must not only accommodate the slotted core member in a secure manner but also be compatible with the wall unit and the bracket. Means must be provided to stabilize the core member both laterally and vertically as it is not inherently stable. Further, ready access to the slots of the core member and the enhancement of bracket stability are quite desirable.
The multiple requirements of a bracket support design have resulted in a number of solutions. Generally, such designs have included a vertical channel for retaining the bracket support core or bar. Numerous configurations have been employed for cooperatively engaging such channel to the remainder of the wall unit. Examples of designs that include an upright channel for receiving a slotted support bar and that are adapted to be secured to a wall are disclosed in the following U.S. patents: U.S. Pat. NO. 3,714,748 of Costruba for "Support Structure for Shelving" issued Feb. 6, 1973; U.S. Pat. No. 3,730,477 of J. R. Wavrunek for "Bracket Support Unit for Integral Wall Construction" issued May 1, 1973; U.S. Pat. No. 3,492,766 of W. R. Andrews for "Adjustable Stud" issued Feb. 3, 1970; U.S. Pat. No. 3,509,669 of G. J. Plemeng for "Support Structure for Shelving" issued May 5, 1970; U.S. Pat. NO. 3,407,547 of J. Doke et al. for "Metallic Wall Stud Structure for Supporting Shelf Brackets" issued Oct. 29, 1968; and U.S. Pat. No. 3,394,507 of J. Doke for "Metallic Structure for Interior Walls to Carry Shelf Brackets and Wallboard" issued July 30, 1968.
A critical feature of a practical support design is cost, both of manufacture and of upkeep as wall units are designed for economy. Related to economy of upkeep is the inherent reliability of a design. The bracket supports disclosed in the Costruba, Andrews and Plemeng patents employ angle bars, spot welded to the core support bar, to define a stabilizing outwardly-protruding passageway for the bracket. The angle bars form, with the support bar, a slidable arrangement within the upright channel formed inside the bracket support housing. While such a passageway is advantageous both in terms of bracket stability and protection of the surrounding drywall from chipping and fraying, this type of construction requires numerous fabrication steps and results in a structure that includes numerous welds subject to fracture.
The Wavrunek patent discloses a bracket support in which the passageway is formed of a molded piece integral with an upright housing including an interior channel. However, the increased reliability of this design is achieved only at the cost of the substantial added fabrication costs that result from the extrusion process as opposed to more economical processes such as cold rolling and the like. | {
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Solvent based contact adhesives have long been used where the immediate bonding of two substrates is necessary to be practical for the end user. These products are characterized by their high quality bonds and the speed in which tack is developed. As a result of the very quick set speed of solvent based products, entire industries have built their manufacturing practices around the rapid assembly of parts using solvent based adhesives.
The problems with solvent based products have been well documented. Pressures to reduce emissions and health hazards of solvent based adhesives have caused end users to search for alternatives, creating new opportunities and difficulties for the adhesive formulator. However, the replacement of solvent based adhesives has been difficult to achieve. The requirement to remove the solvent from the adhesive before the final bonds will form, pushed many end users to evaluate hot melt adhesives. Some limited success has occurred replacing solvent based adhesives with hot melts, especially where non-porous substrates have been involved. Porous substrates, however, are more likely candidates for water based formulations because the residual water becomes absorbed by the substrates as the adhesive sets.
When it is realized that most end users apply their contact cements using hand-operated spray application, the difficulties of using hot melts become clear. Aside from the safety implications, spray application of hot melts requires equipment that is expensive and unwieldy compared to what the industry is used to, and the hot melt option becomes impractical. The idea that water based formulations should be easy to apply using a spray-like paint, has led end users to continue to seek water based alternatives for porous substrates.
The properties of solvent based products have been difficult to match. Rubbers used in solvent formulations provide excellent bond qualities. Substrates can be bonded together immediately upon application. The fresh bond (or green strength) is generally adequate to allow further processing (cutting, shaping, flexing, further gluing, packaging, etc.) In addition, the final bond can be formulated to have high strength, yet still be flexible. This is important where the product may experience repeated flexing, as would occur in the use of shoes and home furnishings.
Attempts to formulate water based contact cements with the ability to bond substrates immediately has centered mainly around two basic types of rubber emulsions, namely natural latex and synthetic neoprene and styrene-butadiene emulsions. Occasionally, other synthetics such as acrylics or vinyls have been used. The typical method employed to make these polymers provide immediate tack has been to add acids or acidic additives to the base polymer emulsion(s). The acid causes the stable emulsion to immediately coagulate, breaking down the protective colloid. The unprotected rubber fraction then is exposed, and is tacky. The level of tack is adjusted by the use of tackifiers, plasticizers, or other additives. As long as the adhesive is applied to both surfaces, the unprotected rubber will bond to itself as the two substrates are brought together. The final bond will form when all of the residual water has dried away.
The reaction of the acid is immediate. Therefore, the acid must be added at the point of application. For spray equipment, these products require equipment which will store the emulsion and acid catalyst separately, meter the delivery accurately and then mix the components together thoroughly at the spray head. The equipment, again, is costly and more maintenance dependent than solvent adhesive delivery equipment, thus the use of the two-part adhesive option becomes less practical. However, these products represent a significant improvement over the use of hot melts in practicality, so some success has been seen with two-part acid catalyzed products.
Of the two emulsions most widely explored (natural latex and neoprene emulsions as stated previously), natural latex has properties that has drawn adhesive formulators' attention for use in instant bonding contact cements. Aside from the fact that natural latex, over history, has been far less costly than synthetic neoprene, natural latex has the unique property to adhere quickly, termed "fast break". This is characteristic of the natural latex emulsion particle to become unstable and create tack. When compression or shear force is applied to the emulsion, the protective colloidial layer of the particle is disrupted, exposing the unprotected rubber, which will then instantly form a rubber film. This property has been used and refined in adhesives where "spotting" tack is desired. In an industry such as footwear construction, sock linings are "spot tacked" in place in the shoe by the application of finger compression against the wet adhesive. This property of fast break, and fast emulsion destabilization, has presented the adhesive formulator with an avenue to exploit in search of an adhesive with instant bonding capabilities.
The difficulty of formulating a natural latex adhesive to bond instantly is similar to that of adding acid; the end result is fluid instability. Additives which enhance the "break" of natural latex also cause the viscosity of the emulsion to rise, eventually creating gelation, rendering the adhesive unusable. For practicality, an adhesive must have enough fluid stability to be mixed, shipped, stored and used. A typical shelf life expected by adhesive users is six months. A minimum shelf life of about two months is necessary simply to allow enough time for a product to be produced, shipped and used. For this reason, a balance of fluid stability and instant tack capability is required.
It has been unexpectedly discovered that the addition of a single additive to natural latex, in an effective amount, results in an adhesive with instant tack, good green strength and enough fluid stability to allow for manufacturing, shipping, storage and use (approximate shelf life of six months). The invention comprises the use of chlorinated alkyl phosphate plasticizer oils (sold commercially as fire retardants) which provide enough instant tack to be developed, yet enough stability to be practical. It is thought that the oil associates with the natural latex emulsion, resulting in a characteristic thickening response which stabilizes after several days. Once the oil has fully incorporated itself, the latex emulsion will destabilized very rapidly and substrates can be bonded immediately.
The invention is uniquely suited for use as a contact cement for porous substrates. Because the product is fluid stable, it can be pumped from a central location through plastic piping to multiple spray guns, making the delivery system very cost effective. Through the selection of the nozzle sizes and fluid pressures, the initial tack speed of the adhesive can be maximized. This is because the partially unstable latex emulsion will rapidly destabilize as the adhesive experiences the shear force of passing through a spray nozzle. Proper spray atomization will also allow for water and ammonia to rapidly begin to evaporate, further destabilizing the adhesive. When both substrates coated with adhesive are joined, the exposed rubber will instantly bond to itself. The fresh bond, or green strength, is adequate to allow further processing or handling. Once the water fully dries, the result is a strong, flexible bond functionally similar to solvent adhesives.
In addition to spray application, the adhesive of the invention has also been extruded by nozzle. Edge turning of fabric to form bindings involves compressing the substrates and bead of adhesive together. The compression provides shear force, and the adhesive instantly forms a bond with adequate green strength to allow further handling or processing. The final bond forms once the residual water evaporates. Delivery systems for nozzle extrusion can be by pump, pressure pot, or by gravity flow.
Exemplary chlorinated alkyl phosphate oils used in the invention include tri (2-chloro isopropyl) phosphate, tri (1,3-dichloro isopropyl) phosphate, and tri (2-chloro ethyl) phosphate and blends thereof. Because these oils will provide flame retardancy and burn resistance, the invention is uniquely suited for use in automotive interiors and for home furnishings, where resistance to flame propagation is either mandated or preferred. The use of these chlorinated alkyl phosphate oils in natural latex is also thought to be unique because of the likelihood of hydrolysis, hence destruction, of these materials when exposed to water. The natural latex emulsion appears to provide a unique protection against destruction by hydrolysis and the instant tack and burn-resistance are retained throughout the shelf life of the adhesive. Further, it is believed that aromatic phosphate esters, such as triphenyl phosphate, may also provide similar properties. | {
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The invention relates to a device for adjusting a rotary position of a ring gear in relation to an axially aligned gearwheel.
In reversing or turning devices in rotary printing machines, it has become known heretofore that the gripper devices of the reversing or turning device which grip the trailing edge of the sheet during the reversing or turning operation have to be adjusted as a function of the operating mode and of the format length to be processed.
For this purpose, a cylinder of the reversing or turning device has a gearwheel which is drive-connected to the preceding printing units of a first gearwheel train. The cylinder wheel carries, axially aligned, a ring gear which is drive-connected to the following printing units by a second gearwheel train. The gearwheel and the ring gear are releasably coupled to one another.
A device of this general type has become known heretofore, for example, from the published European Patent Document EP 0 346 619 A1, which discloses, for forcelocking or nonpositive coupling of the gearwheel and the ring gear, a multi-disk clutch, wherein a number of annular coaxially arranged disks are attached resiliently to the gearwheel and a number of annular coaxially arranged disks cooperating with the first disks are screwed resiliently to the ring gear. In this regard, it is noted that a forcelocking connection is one that connects two elements together by force external to the elements, as opposed to a formlocking connection, which is provided by the shapes of the elements themselves.
In the aforementioned published European Patent Document EP 0 346 619 A1, the fastening points for the disks are disclosed as being exposed to high loads in the case of high transmission forces and, therefore, having to be constructed with very high dimensioning.
It is accordingly an object of the invention to provide an alternative multi-disk clutch, which avoids the disadvantages of heretoforeknown clutches of this general type.
With the foregoing and other objects in view, there is thus provided, in accordance with one aspect of the invention, a device for positively coupling one force transmission element with a further force transmission element, comprising a multi-disk clutch formed of at least four disk rings for adjusting the rotary position of the further transmission element in relation to the one force transmission element, the disk rings being axially displaceably mounted and, for both directions of rotation, having a play-free operative connection with the force transmission elements.
In accordance with another feature of the invention, the coupling device includes a gearwheel having a journal extension and, on a seating surface in common with an adjusting gearwheel, has a receptacle for some of the disk rings, and a receptacle for others of the disk rings.
In accordance with a further feature of the invention, each of the disk rings has at least one driver.
In accordance with an additional feature of the invention, some of the drivers of the disk rings are directed radially inwardly, and some of the drivers of the disk rings are directed radially outwardly.
In accordance with yet another feature of the invention, the radially inwardly directed drivers engage in an axially parallel receptacle in the journal extension, and the radially outwardly directed drivers engage in an axially parallel receptacle in a ring gear.
In accordance with yet a further feature of the invention, some of the drivers of some of the disk rings engage in an axially parallel receptacle in the journal extension, and some of the drivers of others of the disk rings engage in the axially parallel receptacle in a ring gear.
In accordance with yet an added feature of the invention, others of the drivers of others of the disk rings engage in the axially parallel receptacle in the journal extension, and others of the drivers of others of the disk rings engage in the axially parallel receptacle in the ring gear.
In accordance with yet an additional feature of the invention, the drivers directed radially inwardly engage, respectively, in two threaded receptacles in the journal extension, and the drivers directed radially outwardly engage, respectively, in two threaded receptacles in the ring gear.
In accordance with still another feature of the invention, two drivers arranged opposite one another are provided for each of the disk rings, each of the two drivers having a starting slope.
In accordance with still a further feature of the invention, the two drivers engage in two opposite receptacles in the ring gear, and the two drivers engage in two receptacles in the journal extension.
In accordance with still an added feature of the invention, some of the disk rings are arranged so as to be shiftable independently of one another for a clockwise direction of rotation, and some of the disk rings are arranged so as to be shiftable independently of one another for a counterclockwise direction of rotation.
In accordance with still an additional feature of the invention, the coupling device includes an abutment arranged between the disk rings for clockwise rotational force transmission and the disk rings for counterclockwise rotational force transmission, and clamping devices operating independently of one another for shifting the various disk assemblies.
In accordance with another feature of the invention, the coupling device includes spring elements disposed in the receptacles for augmenting the bearing contact of the drivers.
In accordance with a further feature of the invention, the spring elements are selected from the group thereof consisting of compression springs, leaf springs, magnets, plastic material and rubber.
In accordance with a concomitant aspect of the invention, there is provided a reversing device of a sheet-fed rotary printing machine having installed therein a device for positively coupling one force transmission element with a further force transmission element, comprising a multi-disk clutch formed of at least four disk rings for adjusting the rotary position of the further transmission element in relation to the one force transmission element, the disk rings being axially displaceably mounted and, for both directions of rotation, having a play-free operative connection with the force transmission elements.
An advantage of the invention is that, due to the location of installation and type of installation of the multi-disk clutch according to the invention, positive force transmission from gearwheel to disk and from disk to ring gear is possible, even in the case of high torques.
To achieve reliable bearing contact (freedom from play and high torsional rigidity) of the elements involved in force transmission, provision is made for arranging axially displaceable disk rings on a journal extension of the gearwheel. These can have a great thickness, and therefore high torsional rigidity, as compared with the conventional flexible disks. Each disk ring has at least one driver which, respectively, engages in a receptacle formed, for example, as a groove. For the play-free transmission of a torque, two different disk rings are necessary for each direction of rotation, more precisely, a first disk ring with an external driver for engaging in the ring gear, and a second disk ring with an internal driver for engaging in the gearwheel or journal extension.
In a preferred embodiment, a number of, for example four disk rings, are arranged as an assembly for torque transmission clockwise and a number of, for example four disk rings, are arranged as a further assembly for torque transmission counterclockwise, the drivers of the disk assemblies, respectively, having to be brought into bearing contact with respective receptacles. At the same time, for the elimination of play, provision is made for arranging in the receptacles elastic spring elements which ensure that the drivers or entrainers are in constant bearing contact on the working side of the receptacle. Mechanical springs, magnets, plastic materials or rubber, and the like are preferably proposed for this purpose. In the preferred exemplary embodiment, each disk ring has three drivers which are arranged at an angle of 120xc2x0 to one another, respectively, and engage with assembly play in the receptacles, in order, in addition to the transmission of a torque, to prevent a displacement of the ring gear due to the tooth forces.
In a further exemplary embodiment, provision is made for ensuring good reliable bearing contact, as free of play as possible, of the drivers in the receptacles by at least two receiving grooves being arranged with slight rifling, i.e., with a slight curvature in the journal receptacle or with opposite curvatures in the ring gear. This measure ensures that, during the closing of the clutch, the drivers provided for torque transmission are brought into bearing contact with the receptacles.
If, in a further development, the radial play is additionally to be forced out during the closing of the clutch made up of the elements transmitting rotational force, provision is made, in order to absorb the displacement forces on the ring gear, for respectively providing two receptacles per ring gear or per journal extension preferably opposite one another and for providing both the drivers and the receptacles with a radially arranged starting or run-on slope.
In the preferred exemplary embodiment, each disk ring has three drivers which are arranged at an angle of 120xc2x0 to one another, respectively, and which engage with assembly play in the receptacles.
Other features which are considered as characteristic for the invention are set forth in the appended claims.
Although the invention is illustrated and described herein as embodied in a multi-disk clutch, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.
The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings, wherein: | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The invention relates to a connecting element for electrically connecting a first component to a second component, and to an associated fluid assembly.
2. Description of the Prior Art
A conventional fluid assembly, which is used for instance in an anti-lock brake system (ABS) or traction control system (TC system) or an electronic stability program system (ESP system), as a rule includes a control unit and a fluid block, which includes at least one fluid component, embodied for instance as a fluid block or pump motor, and at least one fluid control element, which is embodied for instance as a valve cartridge that is part of an associated solenoid valve. For triggering the at least one fluid component and the at least one fluid control element, the control unit includes a printed circuit board, which is simultaneously used as a circuit holder and for attaching a customer plug, located on the housing, and the solenoid valves. The control unit furthermore includes magnet assemblies that are also part of the particular associated solenoid valve and are necessary for adjusting the fluid control elements embodied as valve cartridges. Via electric magnet coils, each of the magnet assemblies generates a magnetic force by way of which the fluid control elements are adjustable, and these fluid control elements adjust volumetric flows that are carried in fluid conduits of the fluid component embodied as a fluid block. The magnet coils typically comprise an ion circuit, a winding holder, and a wire winding, and they can be connected electrically to electronic circuits on the printed circuit board. The electrical magnet coils of the magnet assemblies are electrically contacted via a stamped grating that is electrically connected to at least one electronic circuit of the printed circuit board, and the magnet assemblies electrically connected to the printed circuit board via the stamped grating are mounted on the fluid control elements embodied as valve cartridges, which are for instance firmly connected, and preferably calked, to the fluid component embodied as a fluid block. The stamped grating used, which is very complicated both structurally and in terms of tools, is quite inflexible and can be altered only with difficulty during the service life of the fluid block. Moreover, in conjunction with the printed circuit board technology, a further electrical connection piece, for instance in the form of individual connection pins, is necessary between the stamped grating and the printed circuit board.
In German Published Patent Application DE 44 12 664 A1, for instance, an electrohydraulic pressure adjusting device is described for a slip-control vehicle brake system. The described pressure adjusting device has at least one valve, united with a valve block, having a valve dome protruding from the valve block, under which dome a coil disposed in a cap can be slipped. Electrical contact elements, joined together by material engagement, extend from both the coil and the cap. The electrical contact elements of the coil and of the cap are embodied resiliently. They take on the task of both electrical connection and the retention function for the coil. Moreover, they permit aligning the coil with the valve dome as it is being mounted. The electrical contact elements of the cap are embodied as stamped grating strips, which are cast integrally with the cap that is of an insulating material. The stamped grating strips extend at a right angle to the plane extending along the longitudinal axis of the coil and have meandering offset bends, as a result of which the stamped grating strips have a relatively high elastic resilience in a plane extending at a right angle to the longitudinal compensation of the coil. The stamped grating strips, on their free end, have a securing lug that extends parallel to the associated connection wire of the coil and is joined to it by a material-engagement connection such as welding or soldering. | {
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A pacemaker-mediated tachycardia (PMT), also referred to as endless loop tachycardia, occurs when a pacemaker paces the ventricles at inappropriately fast rates for sustained periods of time. PMT occurs when a ventricular event occurs at a time during which the connective tissue between the atrium and ventricle can transmit retrograde electrical signals from the ventricle to the atrium. The conduction of the ventricular signal to the atrium provides a spurious electrical signal in the atrium that is considered to be a natural atrial event by the pacemaker. The pacemaker senses the spurious retrograde atrial signal and then paces the ventricle at a programmed AV time period following the signal. The paced ventricular signal is conducted to the atrium and is again erroneously detected by the pacemaker as a natural atrial event. The pacemaker therefore continues to pace the ventricle at a relatively high rate defined by the sum of the programmed AV interval and the retrograde conduction time between the ventricle and atrium. The high rate is sustained indefinitely by the pacemaker, because retrograde conduction ensures that the pacemaker detects what appear to be high rate atrial events and tracks these spurious atrial events by generating corresponding high rate ventricular paces.
PMT can be caused by retrograde conduction following a premature ventricular contractions (PVC), a right ventricular (RV) pace can produce retrograde conduction back up to the atrium. In response to the retrograde conduction, an atrial sensed event to be detected by the implanted device which in turn causes an RV pace to be deliver at the programmed sensed atrioventricular (SAV) interval. This produces a cycle of inappropriately fast pacing by the device called PMT, as described in U.S. Pat. No. 4,554,920 to Baker et. al.
Existing algorithms for detection of PMT may be able to achieve improved PMT detection, especially for patients experiencing high intrinsic rates. High intrinsic rates can lead to inappropriate PMT intervention (e.g. extending post-ventricular atrial refractory period (PVARP) for one cycle) which can lead to dropped beats or the interruption of CRT pacing. It is therefore desirable to develop devices and methods that are configured to avoid, eliminate, terminate or reduce PMTs. | {
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Plural security protocols have been put into service, in which two (or more) communicating parties involve either directly, in the protocol messaging, or in their setup a trusted third party that both parties have a trust relation with. The most prominent class of protocols resides in secure communication protocols like Secure Shell/Transport Layer Security (SSL/TLS), Datagram TLS (DTLS), Wireless TLS (WTLS), and Internet Protocol Secure (IPSec) when using digital certificates.
In those protocols, a Certificate Authority (CA) that signs the certificates, may be the trusted third party and the (self-signed) certificate of the CA may be used (trusted) by the communicating parties to verify the correctness of the certificates used in the protocol. Other examples, where such a setup is applied, is the Kerberos protocol or the UMA implementation of the OAuth2.o protocol.
FIG. 1 shows a principle underlying the prior art, and shows a network 100 comprising a Trusted Third Party (TTP) 1001 and at least two clients 1002.
Those protocols are considered, in which the knowledge and involvement of the TTP 1001 concerning the security protocol implies that the TTP 1001 issues information that the data (such as keys or credentials) used in the protocol is still to be trusted by the parties for its purpose.
FIG. 1 involves a Public Key Infrastructure (PKI), which means that the TTP 1001 (e.g. the CA) can provide information that the certificate(s) can still be trusted. In practice, this is often realized by using so-called Certificate Revocation Lists (CRL) on which revoked certificates are listed, or through an on-line protocol like Online Certificate Status Protocol (OCSP).
So, either the communicating parties 1002 may have copies of a CRL or can use OCSP (or both). Typically, the CA 1001 uses a server to run OCSP or to distribute CRLs. | {
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In various portable and mobile devices, camera based systems may be incorporated which are configured to serve for depth sensing of objects present in a target region shot by the camera. The depth sensing may be carried out on the basis of one or more digital images captured by the camera of the target region while illuminating the target region by structured illumination. The depth information generated by the depth sensing may be used for various purposes and applications, such as three dimensional mapping of the target region, distance measurements, and gesture based user interfaces, to mention few examples.
Accuracy and reliability of the depth sensing may be affected by the accuracy and stability of the structured illumination projected as structured light pattern(s) onto the target region. | {
"pile_set_name": "USPTO Backgrounds"
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An optoelectronic component (e.g. an organic light emitting diode (OLED), for example a white organic light emitting diode (WOLED), a solar cell, etc.) on an organic basis is usually distinguished by a mechanical flexibility and moderate production conditions. Compared with a component composed of inorganic materials, an optoelectronic component on an organic basis can be produced potentially cost-effectively on account of the possibility of large-area production methods (e.g. roll-to-roll production methods).
An organic optoelectronic component, for example an organic light emitting diode or an organic solar cell, can have an anode and a cathode with an organic functional layer system therebetween. These layers can be applied on a carrier and coated with an encapsulation layer.
Conventionally, two methods are known for the electrical linking of the organic optoelectronic component.
In one conventional method, the optoelectronic component is mechanically fixed by a clamping device in a housing, frame or the like. The electrical linking can be formed by clamping contacts or spring pins on contact strips of the organic optoelectronic component.
In a further conventional method, connection pieces, for example flexible printed circuit boards (flex-PCB) or metal tapes are applied to an optoelectronic component by various methods, for example adhesive bonding by electrically conductive adhesives (anisotropic conductive film bonding—ACF bonding), a friction welding process (ultrasonic bonding) or the like. In this case, the optoelectronic component can in turn be mechanically fixed by a clamping device. For the electrical linking of the organic optoelectronic component, said connection pieces can be electrically contact-connected to electrodes by soldering connections or by electromechanical positively locking engagement.
The exposed surface of the connection pieces, for example chromium, and the soldering tin are often not compatible, i.e. miscible, with one another. An arbitrary flow of the soldering tin on the exposed surface of the connection piece can occur as a result. The flowing soldering tin can then make it more difficult to precisely position the terminals on the soldering location.
Conventional methods for restricting the solderable regions use soldering resist or soldering pad forms (constrictions). | {
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This application claims the priority of German application 197 16 292.4-14, filed in Germany on Apr. 18, 1997, the disclosure of which is expressly incorporated by reference herein.
The invention relates to an extrusion arrangement for manufacturing bent workpieces, having an extrusion die which is guided in an extrusion chamber, which compresses material situated in the extrusion chamber and which presses it through a bottom die arranged at a head-side end of the extrusion chamber, at least two bottom die elements being provided which are arranged behind the bottom die in a parallel adjoining manner.
An extrusion arrangement of this type is known from German Patent Document DE 41 31 332 A1. The extrusion arrangement described there comprises a tool core with an adjoining tool jacket which consists of disk-type, assembled jacket parts. The jacket parts, which are fixedly placed upon one another, together with their supplementing duct sections, form a circular-arc-shaped duct. The described division of the tool jacket into individual segments facilitates the manufacturing in that the duct in the individual segments can be premachined and, when all jacket parts are assembled, can then be processed to form the finished product. For producing an internal profile, rods are provided in the case of the known extrusion arrangement which reach into the circular-arc-shaped duct and which expediently also have a curved design.
From European Patent Document EP 0 706 843 A1, an arrangement is known which is used for the manufacturing of curved solid and hollow profiles with complex cross-sections by means of a combination of extruding and bending, the workpiece being bent simultaneously with or immediately after the forming extrusion process by means of a force acting upon the workpiece transversely to the extruding direction. For this purpose, a device generating a transverse force is arranged behind the bottom die viewed in the extruding direction, which device can be pressed against the emerging billet, a bending zone existing in the space between the extrusion surfaces and the outlet zone which is free of contact surfaces.
From German Patent Document DE-AS 11 07 926, a spraying head for extruding is known for manufacturing curved workpieces from thermoplastic material, in the case of which a ram body is arranged spaced from the nozzle outlet of the spraying head, which ram body is constructed as a slider, which is provided with a recess and is guided transversely to the nozzle duct, or as a rotatable ring with an eccentrically situated opening. By the adjustment of this slider or ring with respect to the normal position, the passage cross-section for the emerging thermoplastic mass is changed on one side, which causes a desired speed difference during the exit from the mouthpiece.
From German Patent Document DD-PS 28 365, an extrusion head for extruding presses is known for manufacturing workpieces from ceramic masses which, for reducing a texture formation, consists of several firmly assembled segments whose inside diameter has a partially conical and partially cylindrical construction.
Based on this state of the art, it is an object of the present invention to provide an extrusion arrangement of the initially mentioned type, in the case of which, immediately following the extruding operation, a stretching-bending operation is possible which is as simple and as space-saving as possible and which permits the manufacturing also of complex, spatially bent profiles.
For achieving this object, an extrusion arrangement is provided for manufacturing bent workpieces, having an extrusion die which is guided in an extrusion chamber and which compresses material situated in the extrusion chamber and presses it through a first bottom die arranged at a head-side end of the extrusion chamber, further bottom die elements being provided which are arranged in a parallel adjoining manner behind the first bottom die, wherein the further bottom die elements are displaceably and rotatably disposed such that their successive passage openings form an extrusion duct of a variable curvature and twist.
Accordingly, in preferred embodiments of the invention, further bottom die elements are provided which are arranged behind the bottom die of the extrusion arrangement and which adjoin one another in parallel and with respect to the bottom die. The further bottom die elements are displaceably and rotatably disposed such that their successive passage openings form an extrusion duct whose curvature and twisting are variably and individually adjustable. Preferably, the further bottom die elements can be adjusted continuously and can be fixed in the desired position. Advantageously, the displacement of the bottom die elements takes place in parallel to the bottom die of the extrusion arrangement; that is, perpendicularly to the exiting direction of the extruded profile from the extrusion chamber. The rotating of the further bottom die elements advantageously takes place in a plane in parallel to the plane of the bottom die of the extrusion arrangement; that is, in a plane which is situated perpendicularly to the exiting direction of the extruded profile from the extrusion chamber. According to the invention, the adjoining further bottom die elements therefore form an extrusion duct into which the extruded profile enters after its exiting from the extrusion chamber and the outlet opening of the bottom die. Because of the displaceability and the twisting capacity of the further bottom die elements, the extrusion duct can be provided with an arbitrary curvature and/or a twisting, so that the wall of the extrusion duct formed by the passage openings of the further bottom die elements exercises a transverse force onto the extruded profile.
According to certain preferred embodiments of the invention, the passage openings of the further bottom die elements have rounded edges. As a result, a passage of the extruded profile through the passage openings of the further bottom die elements is ensured without any problem.
In a further development of certain preferred embodiments of the invention, a holding device for the further bottom die elements is provided which is preferably exchangeable so that a different number of bottom die elements can be arranged behind the bottom die of the extrusion device and extrusion ducts of different lengths can therefore be produced.
In a particularly advantageous further development of certain preferred embodiments of the invention, the bottom die of the extrusion arrangement is part of this holding device. As a result, the extrusion arrangement according to the invention has a particularly simple construction and the bottom die can be exchanged without any problems as required.
In a further development of preferred embodiments of the invention, a stationary crosshead of the extrusion arrangement is arranged to be spaced from the further bottom die and from the bottom die elements, for example, by being acted upon by the holding device. For drawing the curved extruded profile off in front of the stationary crosshead, a lateral opening is advantageously provided for this purpose in the holding device.
In order to permit a manufacturing of hollow profiles, in a particularly advantageous further development of certain preferred embodiments of the invention, an arbor is provided in the interior of the extrusion chamber which is arranged essentially concentrically with respect to the exit opening of the bottom die.
So that the hollow cross-section is also maintained in the extrusion duct for bending the billet, the arbor advantageously has an extension which reaches through the exit opening of the bottom die and into the passage openings of the further bottom die elements.
It was found to be particularly advantageous for the extension to consist of a plurality of segments which are movably connected with one another and which are able without any problem to adapt to a curvature defined by the displaceable and rotatable bottom die elements.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings. | {
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The invention pertains to wireless communications and, more particularly, by way of example, to methods and apparatus providing multiple user detection for use in code division multiple access (CDMA) communications. The invention has application, by way of non-limiting example, in improving the capacity of cellular phone base stations.
Code-division multiple access (CDMA) is used increasingly in wireless communications. It is a form of multiplexing communications, e.g., between cellular phones and base stations, based on distinct digital codes in the communication signals. This can be contrasted with other wireless protocols, such as frequency-division multiple access and time-division multiple access, in which multiplexing is based on the use of orthogonal frequency bands and orthogonal time-slots, respectively.
A limiting factor in CDMA communication and, particularly, in so-called direct sequence CDMA (DS-CDMA), is interference—both that wrought on individual transmissions by buildings and other “environmental” factors, as well that between multiple simultaneous communications, e.g., multiple cellular phone users in the same geographic area using their phones at the same time. The latter is referred to as multiple access interference (MAI). Along with environmental interference, it has effect of limiting the capacity of cellular phone base stations, driving service quality below acceptable levels when there are too many users.
A technique known as multi-user detection (MUD) is intended to reduce multiple access interference and, as a consequence, increases base station capacity. It can reduce interference not only between multiple transmissions of like strength, but also that caused by users so close to the base station as to otherwise overpower signals from other users (the so-called near/far problem). MUD generally functions on the principle that signals from multiple simultaneous users can be jointly used to improve detection of the signal from any single user. Many forms of MUD are discussed in the literature; surveys are provided in Moshavi, “Multi-User Detection for DS-CDMA Systems,” IEEE Communications Magazine (October, 1996) and Duel-Hallen et al, “Multiuser Detection for CDMA Systems,” IEEE Personal Communications (April 1995). Though a promising solution to increasing the capacity of cellular phone base stations, MUD techniques are typically so computationally intensive as to limit practical application.
An object of this invention is to provide improved methods and apparatus for wireless communications. A related object is to provide such methods and apparatus for multi-user detection or interference cancellation in code-division multiple access communications.
A further related object is to provide such methods and apparatus as provide improved short-code and/or long-code CDMA communications.
A further object of the invention is to provide such methods and apparatus as can be cost-effectively implemented and as require minimal changes in existing wireless communications infrastructure.
A still further object of the invention is to provide methods and apparatus for executing multi-user detection and related algorithms in real-time.
A still further object of the invention is to provide such methods and apparatus as manage faults for high-availability. | {
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Metal-air cells typically include a metal anode, an air cathode, and a separator all disposed and supported in some sort of container. The metal anode usually comprises a fine-grained metal powder, such as zinc, aluminum, or magnesium, which is blended together with an aqueous electrolyte, such as potassium hydroxide, and a gelling agent into a paste. The separator is a porous material that allows the passage of electrolyte between the cathode and anode, but prevents direct electrical contact therebetween and short circuiting of the cell.
The air cathode is a catalytic structure designed to facilitate the reduction of oxygen. Typically, it is composed of active carbon, a binder, and a catalyst which, together with a metal current collector, are formed into a thin sheet. The air cathode also commonly incorporates a hydrophobic polymer, such as polytetrafluoroethylene or polystyrene, directly into the cathode sheet and sometimes also as a coextensive film. The hydrophobic polymer prevents electrolyte from flooding the cathode or passing through it and leaking from the cell. The container includes oxygen access openings, diffusion chambers and the like which are designed to allow sufficient oxygen to reach all parts of the air cathode.
Metal-air cells have high specific energies. In fact, zinc-air cells have the highest specific energy, up to 450 Wh/kg, of all aqueous primary systems, and high energy per unit volume as well. The components of zinc-air cells also are relatively benign.
Because of their high energy density, button cells incorporating zinc-air chemistry are the most popular batteries for hearing aids. The much larger majority of electronic devices, however, has higher energy requirements requiring the use of larger (i.e., greater than one ampere-hour capacity) cells or batteries. Despite the electrochemical advantages of metal-air and especially zinc-air systems, carbon-zinc and alkaline manganese dioxide systems continue to dominate the much larger world market for larger primary batteries.
Many portable electronic devices, such as portable computers, also place severe constraints on battery weight and volume. In such applications, prismatic cells would be preferable over button or cylindrical cells, which latter type of cells, in general, require more space to be allocated in the device than the cells themselves actually occupy. Prismatic cells also can be much thinner than alkaline cells of equivalent capacity.
Attempts to scale up and reconfigure zinc-air button cells to a larger, prismatic configuration, however, have generally failed. Zinc-air batteries currently are not a competitive option for use in the full spectrum of consumer and electrical products, and they represent a small portion of all primary batteries sold today.
A major problem has been in achieving an inexpensive, light-weight and easily constructed prismatic configuration which is leak-proof, but which provides for efficient electrochemical discharge of the cell. The design of conventional zinc-air button cells and existing manufacturing procedures have not solved the problems for prismatic cells.
A further and significant problem concerns designing a prismatic zinc-air cell that would be amenable to assembly for mass production.
It is important, but sometimes difficult, to prevent electrolyte and anode paste from contacting sealing surfaces. Virtually all commercial zinc-air button cells utilize a multicomponent container, at least one part or subassembly of which is shaped substantially like a cup. A preconstituted anode paste may be filled into the cup. Alternately, a dry mix of zinc and gelling agent may be poured into the cup, after which aqueous electrolyte is added. In either event, the process of loading the cup can be relatively messy. Paste or electrolyte may be spilled onto the sealing surface of the cup in the loading process.
Also, at times too much anode material may be loaded into the cup, and the excess material squeezed into sealing areas when the container is assembled. If anode paste or electrolyte contaminates container sealing surfaces through such processing accidents or any other mechanism, it can cause imperfections in the seal through which leaks may occur. In larger cells, the area which must be sealed is correspondingly larger, and thus, the likelihood of defects occurring in the seal is correspondingly greater.
It also is important to control relatively precisely the amount of gelled zinc anode paste which is incorporated into a cell. By doing so, costs may be controlled more closely; and cells having more uniform discharge capacities will be produced. As noted, if too much anode material is loaded into a cell container, the excess anode material also may be squeezed into sealing areas when the container is assembled.
If the container is constructed from plastic materials, however, problems may be created if too little anode material is dispensed into the container. Most commercial zinc-air cells have conductive, metal containers, and the gelled zinc anode paste is in intimate contact with the container. Plastic is nonconductive, and so zinc-air cells with plastic containers must incorporate an anode current collector. Such collectors often are in the form of a thin metal sheet or wire grid, and such current collectors should be in intimate electrical contact with the anode to the greatest extent possible. If too little gelled zinc anode paste is dispensed into the cell, electrical contact between the current collector and the anode may be impaired.
It seems apparent that, for considerable time, there has existed a substantial need for larger prismatic metal-air cells, especially for thin prismatic zinc-air cells, which can satisfy the energy requirements for a wide variety of applications. It seems further apparent that a considerable amount of effort has been directed to providing suitable cells capable of providing satisfactory performance. Yet, despite recognition of the need and the considerable efforts made to date, there still exists the need for prismatic, and especially for thin prismatic metal-air cells such as zinc-air, which can provide satisfactory and reliable performance for a wide variety of commercial applications.
An object of this invention, therefore, is to provide a prismatic metal-air cell which provides more reliable electrochemical performance in service. A related and more specific object is to provide a thin prismatic zinc-air cell having satisfactorily reliable electrochemical performance in service.
It also is an object to provide a prismatic zinc-air cell having a gelled zinc anode which is more leak resistant. A related object is to provide such a cell wherein the container parts may be sealed together more reliably.
Another object of this invention is to provide a prismatic zinc-air cell having a gelled zinc anode in which the amount of gelled zinc anode paste dispensed into the cell is more precisely controlled.
It is a further object of this invention to provide prismatic zinc-air cells having a gelled zinc anode and a plastic container, wherein more reliable contact between the gelled zinc anode and the anode collector is provided.
Yet another object of this invention is to provide a prismatic zinc-air cell which is simple in design and easily and economically manufactured in mass production.
It also is an object of this invention to provide a method of fabricating prismatic zinc-air cells with a gelled zinc anode which produces more reliable sealing of container parts.
Another object is to provide such methods which control more precisely the amount of gelled zinc anode paste dispensed into a cell.
It is a further object of this invention to provide a method for fabricating a prismatic zinc-air cell with a gelled zinc anode and a plastic container which produces more reliable contact between the gelled zinc anode and the anode collector.
Yet another object of this invention is to provide a prismatic zinc-air cell with a gelled zinc anode and methods for fabricating such cells wherein all of the above-mentioned advantages are realized.
Those and other objects and advantages of the invention will be apparent to those skilled in the art upon reading the following detailed description and upon reference to the drawings. | {
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To reduce the cost and increase the performance of electronic computers, it is desirable to place as many electronic circuits in as small a region as possible in order to reduce the distance over which electrical signals must travel from one circuit to another. This can be achieved by fabricating on a given area of a semiconductor chip as many electronic circuits as feasible with a given fabrication technology. Typically, these dense chips are disposed on the surface of a substrate in a side by side arrangement with space left there between to provide regions for electrical conductors for electrical interconnection of the chips. The chip contact locations can be electrically connected to substrate contact locations by means of wires bonded between the chip contact locations and the substrate contact locations. Alternatively a TAB tape (which is a flexible dielectric layer having a plurality of conductors disposed thereon) can be used for this electrical connection. Alternatively, the semiconductor chips can be mounted in a flip-chip configuration wherein an array of contact locations on the semiconductor chips is aligned with and electrically connected to an array of contact locations on the substrate by means of solder mounds disposed between corresponding chip and substrate contact locations. The side by side arrangement of electronic devices is not the most dense configuration which can be achieved.
The most dense packaging configuration for semiconductor chips, in particular for memory chips, such as DRAMS, SRAMS, Flash Eproms and the like, may be obtained through the construction of a solid cube of semiconductor chips. The difficult problem to solve for such a cube is providing for electrical connections to the chips. The electrical connections must include power supply, data and address lines and the like.
Prior art shows that it is possible to construct dense packages of stacked semiconductor wafers or chips. The major problems are that of interconnecting the chips electrically and that of solving the problem of thermal dissipation. Chips are generally stacked in orthogonal rectangular or cubic structures.
As used herein, an orthogonal rectangular or cubic package refers to a package wherein either square or rectangular chips are stacked directly on top of each other with the edges thereof of adjacent chips aligned.
The electrical connections are handled generally in three manners: (1) Fabricate vias through the semiconductor structures to facilitate interconnections; (2) metallization is carried up to and past the edge of the chips and are also placed on the sides of the stack; (3) chips are bonded on carriers which bring electrical connections past the edges of the chip. The carriers are in turn stacked in orthogonal rectangular or cubic structures.
Generally, the problem of thermal dissipation is either not addressed or is handled by conduction through the structures to the environment.
IBM Technical Disclosure Bulletin, Vol. 14 (9), 2561 (1972) "Bubble Domain 3-Dimensional Magneto-Optic Memory", H. Chang, describes a non-orthogonal stack of chips whose faces are offset so as to allow laser access to one row of pads on each chip. No plan for electrical contact, I/O for power, board mounting or cooling is provided.
U.S. Pat. No. 4,500,905, "Stacked Semiconductor Device with Sloping Sides", describes a non-orthogonal package wherein semiconductor layer fabricated upon one another, are metallized to the edge, and contacts are made on the face of a solid composed of stacked semiconductors. However, the face of the solid is slanted, making the stack into a pyramid rather than a parallelepiped shape. Additional semiconductors are fabricated mounted on the four sides of the pyramidal structure. No cooling means are provided. No means are provided for electrical connection to a board or higher-level package.
It is an object of the present invention to provide an electronic device structure wherein at least one electronic device has at least one edge with at least one contact location thereon. The edge of the electronic device having the contact location is disposed against a substrate having at least one contact location. The electronic device subtends a non-orthogonal angle with respect to the substrate.
It is another object of the present invention to provide a non-orthogonal electronic device package having a plurality of electronic devices in a stack wherein each electronic device has an edge having at least one contact location. The edges with the contact locations thereon are arranged in a stepped or staircase arrangement.
In another more particular aspect of the present invention, the stepped region of the chip stack is disposed against a substrate having a plurality of contact locations thereon for electrical connection to corresponding contact locations on the stepped surface of the chip stack.
These and other objects, features and advantages of the present invention will be more readily apparent to those of skill in the art from the following specification and the appended drawings. | {
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1. Field of the Invention
The present invention relates to an authenticity indicator to be used to indicate that an article or the like is authentic, and particularly to an authenticity indicator whose authenticity can be checked easily and accurately. The present invention also relates to an authenticity checking method for checking the authenticity of an authenticity indicator to be used to indicate that an article or the like is genuine, and an authenticity checking system useful for checking the same, and particularly to an authenticity checking method and system by which the authenticity of the authenticity indicator can be checked easily and accurately.
2. Related Art
Hologram labels, etc. using holograms, serving as authenticity indicators (identification media), have been attached to genuine articles as a means of preventing forgery of cards, passports, ID cards, gift certificates, etc., or of detecting forgeries, fakes, or the like. It is therefore essential for the authenticity indicators that they are difficult to be forged and that the authenticity of the authenticity indicators themselves can be checked accurately.
In recent years, however, techniques for forgery of holograms of this type have advanced, and holographic materials have become easily available, so that there are possibilities that the hologram labels might be skillfully forged and that the forged hologram labels might be overlooked while they are practically used.
Cholesteric liquid crystals, which have both polarized-light selectivity and wavelength selectivity and reflect light so that the reflected light changes in color when an observer changes his viewing angle, have also been used for authenticity indicators. However, forgery techniques have advanced in recent years, and even authenticity indicators using cholesteric liquid crystals are in danger of forgery.
Authenticity indicators using holograms and cholesteric liquid crystals in combination are now being developed (e.g., Japanese Patent Publication No. 3652487 and Japanese Laid-Open Patent Publication No. 2000-211300).
Japanese Patent Publication No. 3652487 discloses an authenticity indicator using a relief hologram layer and a cholesteric liquid crystal layer in combination. In this authenticity indicator, the cholesteric liquid crystal layer is used as a layer for reflecting the relief hologram. Since relief holograms are relatively easy to be forged, the authenticity indicator disclosed in this patent publication can only have a forgery preventing effect comparable to that of an authenticity indicator using a cholesteric liquid crystal layer alone.
Japanese Laid-Open Patent Publication No. 2000-211300 discloses an authenticity indicator using a reflection hologram layer and a cholesteric liquid crystal layer in combination. In this authenticity indicator, the cholesteric liquid crystal layer serves as a layer for reflecting light that has passed through the reflection hologram without being diffracted by it. The reflection hologram layer diffracts (reflects) only light with wavelengths in a narrow wavelength range centering around a specified wavelength, responding to the wavelength selectivity of the reflection hologram. This authenticity indicator is therefore disadvantageous in that it is difficult to confirm the authenticity of the authenticity indicator by the diffracted light from the reflection hologram layer, or that an expensive device such as a highly sensitive light-receiving unit is needed for authenticity checking. | {
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The invention relates to a process for a compacting porous structural member having a complicated shape and an optional size by encapsulation of the member with a material of the same type and which is capable of sintering, and subsequently subjecting the encapsulated member to hot-isostatic pressing.
Molded articles made of ceramic non-oxidic materials such as, for example, silicon nitride, silicon carbide, boron nitride or boron carbide have continued to come into wider use. Such molded articles or structural members are very porous and, thus, require treatment to reduce their porosity.
A known process for reducing the porosity of such molded articles, for example, involves hot-isostatic molding or hot-isostatic pressing. Since a gas is used in this process as the medium for transferring pressure, the porous ceramic bodies have to be encapsulated by a gas-tight capsule prior to compacting the same. Because of the high compacting temperatures of silicon nitride, silicon carbide, boron nitride and boron carbide from which such molded articles are usually made, glasses having high softening temperatures such as, for example, fused silica Vycor.sup.(R)* or Duran.sup.(R)** glass are almost exclusively employed as capsule materials. FNT *Reg. TM, Corning Glass Works, Corning, NY, USA FNT **Reg. TM, Jenaer Glaswerk Schott & Gen, Mainz, West Germany
However, various crucial disadvantages are inherent in the use of a glass as the capsule material. For example, reactions will occur between the glass envelope and the ceramic molded articles at the high compacting temperatures employed which are in excess of 1600.degree. C. In addition, the above-mentioned glasses all have very much smaller coefficients of thermal expansion than th ceramic molded articles. Consequently, upon cooling very high stresses occur which may result in complete destruction of the molded articles or structural members. Still further, great difficulties are involved in removing the glass capsule envelope from such molded articles after hot-isostatic molding.
In German Offenlegungsschrift No. DE-OS 30 47 237 there is described a process which avoids such drawbacks. The described process, porous bodies made of a ceramic material and having a complicated shape, such as, for example, turbine blades, are encompassed or coated with an inert pressing powder such as, for example, boron nitride powder, and then melt-encapsulated in quartz glass capsules prior to being subjected to hot-isostatic molding. The boron nitride powder prevents the capsule material from reacting with the material of the structural member so that upon cooling, no stresses will occur and after hot-isostatic pressing the capsule can be readily removed. The described process is well suited for manufacturing turbine blades.
However, when larger structural members such as, for example, turbo-supercharger rotors or monolithic turbine wheels are to be compacted, the glass capsules have to be more voluminous. In such cases, however, they become so expensive that economical manufacture of such structural members is no longer possible.
In the DE-OS No. 28 12 986, there is described a process in which a structural member made of silicon nitride, which contains a compacting aid, is employed. The porous article is coated with a silicon nitride skin having a thickness from 25 to 250 .mu.m. In a subsequent heating step, part of the compacting aid is supposed to diffuse from the molded article into the silicon nitride skin. It is intended thereby to cause the silicon nitride layer to be compacted by undergoing a further temperature treatment so that it can be subjected to a high pressure atmosphere without cracking. Several crucial drawbacks are inherent in this process. It is known from the literature (e.g., G. Wotting, Dissertation, Technical University, Berlin, 1983, page 9; Sallmang and Scholze, Die physikalischen und chemischen Grundlagen der Keramik, Springer-Vergag, Berlin, 1968) that the diffusion rates in silicon nitride and also in silicon carbide, boron nitride and boron carbide, are extremely low due to the high proportion of covalent bonding of these materials. It follows therefrom that the diffusion from the interior of the structural member to the outside thereof of the compacting aid in an amount sufficiently high so that the external skin will become tight-sealed by sintering which may take several hundred hours. Another drawback resides in the fact that the article to be compacted must itself contain a high proportion of the compacting aid. However, the compacting aids adversely affect the high-temperature properties of the respective materials, while it is precisely these high-temperature properties of silicon nitride, silicon carbide, boron nitride and boron carbide containing no compacting aid that render these materials so attractive for making high precision structural members. Another disadvantage resides in the fact that the silicon nitride skin, as applied, will become an integral component of the finished article. However, in the manufacture of high precision structural members, the requirements as to homogeneity of the silicon metal slip, accuracy of the casting procedure, maintenance of the conditions in the nitrideforming step and diffusion of the compacting aid are very difficult to achieve in the described process of DE-OS No. 28 12 986. Thus, molded articles having varying dimensions will be obtained.
There exists, therefore, a need to provide a process for encapsulating porous molded articles having complicated shapes and optional sizes, wherein the articles or structural members do not have to contain compacting aids, the coefficients of thermal expansion of molded articles and of the capsule materials are compatible with each other, and in which no reactions can occur between the capsule materials and the material of the structural members. The present invention fulfills this need. | {
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Board games continue to serve as a source of entertainment for families, friends, and individuals. Over the years, board games have attempted to integrate electronics into game play. However, in order to offer the board games at prices that are attractive to consumers, the board games often have had limited electronic integration, and have included the electronics as part of the board game itself.
At the same time, touch screen devices have become increasingly prevalent in the marketplace, and people of all ages have come to enjoy game play experiences offered on touch screen devices. These touch screen devices offer a touch sensitive surface over a display and can detect the presence and position of touch input, opening up the possibility of new ways to interact with electronic devices.
However, most board game simulations on touch screen devices include the entire board game on the touch screen device as an electronic board game. For example, games like Monopoly® can be played entirely on touch screen devices. However, despite such advancements, there is still a strong market for more traditional board game experiences, yet there is a shortage of inexpensive, hybrid game play experiences, that capitalize on the traditional physical board game experience while integrating the electronic board game with touch screen devices. | {
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1. Field of the Invention
This invention relates to a method for producing near net forgings for ring gears, especially ring gears of the hypoid, straight-bevel or spiral-bevel type for heavy-duty truck drive axles, from rolled ring shaped blanks produced by ring rolling of forged preforms.
2. Description of the Prior Art
Right angle drive trains for heavy-duty drive axles utilizing pinion gears/ring gear gear-sets are well known in the prior art, as may be seen by reference to U.S. Pat. Nos. 3,265,173; 4,018,097; 4,046,210; 4,050,534; 4,263,834 and 4,651,587, and to SAE Paper No. 841085, the disclosures of all of which are hereby incorporated by reference. Such gear-sets are usually of the well known spiral-bevel or hypoid gear type or some modification or derivative thereof.
Forging processes for the production of gear forgings/gear blanks having at least partially formed teeth are well known in the prior art, especially for relatively smaller sized bevel gears, such as differential pinion and side gears, as may be seen by reference to U.S. Pat. Nos. 3,832,763; 4,050,283 and 4,590,782, the disclosures of which are all hereby incorporated by reference.
The ring rolling process whereby generally annular rings are ring rolled from ring rolling preforms is also well known in the prior art as may be seen by reference to U.S. Pat. Nos. 1,971,027; 1,991,486; 3,230,370; 3,382,693; and 4,084,419, and to Metals Handbook, 8th Edition, Volume 5, American Society for Metals, Pages 106 and 107, "Ring Rolling", the disclosures of all of which are hereby incorporated by reference.
In the past, due to the relatively massive size, ring gears for heavy-duty trucks have been produced by a method comprising the forging of a gear blank having outer diameter flash and a center slug, trimming of the forged gear blank, a normalizing heat treatment of the trimmed gear blank, extensive machining of the gear blank to rough and then final cut gear teeth therein, other machining of surfaces and mounting bores, a carburizing heat treatment, a lapping operation wherein the ring gear and a pinion gear are rotated in meshing engagement in a lapping compound, and then maintaining the ring gear and pinion gear as a matched set to be used only in connection with one another.
While the prior art method for producing ring gears for heavy-duty trucks has been utilized for many years as have the ring gears and ring gear/pinion gear-sets produced thereby, this method is not totally satisfactory as the billets used therein are of a considerably greater volume than the finished ring gear representing undesirably high material and heating costs, cutting of the gear teeth from the gear blanks is an expensive and time consuming operation and teeth formed by a cutting process do not possess the desirable grain flow characteristics inherent in gear teeth formed by a material deformation process and thus do not provide the performance of formed gear teeth. Also, as the lapped ring gear/pinion gear gear-sets are only usable as a matched pair, great care must be taken to maintain the gear-sets in matched pairs and damage to either the ring gear or pinion gear will render the entire gear set useless.
The forging of hollow members from rolled rings to save material is generally known in the prior art. However, this process usually is economical only for high volume production because ring rolling of the blanks requires a forming operation (on a forge press or hammer) to produce the annular preform to be ring rolled. The material savings, and other savings associated therewith, were not sufficient to make such a method economically desirable, especially as to the relatively larger more costly ring gears, in the volume and variety of sizes and ratios associated with heavy-duty drive axles (i.e. drive axles utilized with heavy-duty trucks, off-the-road construction vehicles and the like). This was because prior art production of preforms, as with most other forging operations, had the conventional wisdom that the preform die must be filled to nearly one hundred percent (100%) of its theoretical capacity and thus each different sized preform would require a separate die and, for relatively small lots, the material savings would be more than offset by the additional preform tooling and press setups normally required. | {
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Boarding and disembarking a boat from the water or while beached on a shoreline has often proved difficult. The ability to move on and off the boat easily during an outing is an essential aspect for swimming or ferrying passengers back and forth to shore. A sturdy platform to gain access up the side of the boat can make or break the boating experience. Its importance can be gauged by the many efforts to provide a ladder or platform for this purpose.
Current schemes use essentially two mechanisms for boarding and disembarking a boat. One mechanism uses a temporary boarding ladder. Another mechanism uses a permanently mounted swim platform and ladder.
Temporary boarding ladders can be split into two types; rope style and solid frame hook style. Rope style ladders are easy to store and require no mounting hardware but require the talents of a gymnast to ascend successfully. They have no center or bottom stability and swing easily on a curved hull, making them all but impossible for those with limited physical ability to ascend. They also have narrow ladder rungs which make them treacherous to mount from a bobbing dingy or shore boat.
Hook style ladders provide a solid frame but still have the narrow rung affliction. In addition, the hook style top can only be mounted over the gunnel or sides of the boat. Mounting a hook style ladder over the gunnel or the side of the boat drastically limits the locations where a hook style ladder can be used. Some ladder styles afford permanent mounting brackets, limiting location further.
Permanently mounted swim platforms provide greatly improved stability and usefulness, but as implied, are permanently located in one spot (usually the transom) and are unable to be easily relocated or adjusted thus limiting locations from which to board the boat. Side mounting is typically not available because it would get in the way during docking. | {
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Archery bows are designed to accommodate a specific range of human factors, including the user's arm span. Arm span is associated with the bow's draw length. A user can determine his/her personal draw length using various methods. One method involves measuring his/her arm span and dividing that measurement by 2.5. Once the user knows his/her personal draw length, the user can purchase a bow designed to accommodate such draw length. However, users often have the need for various draw lengths. For example, a single user may use different bows with slightly different draw lengths. Also, a single user may need different draw lengths to achieve a consistent anchor point on the user's face regardless of variables that affect the draw length, such as the particular bow used or the bowstring angle. In another example, a user may prefer a relatively short draw length for shooting events requiring greater shooting form and accuracy, and the same user may prefer a relatively long draw length for shooting events requiring greater speed. Also, if a user is still growing, such as a child, his/her draw length can significantly increase from time to time, requiring changes in draw length. Furthermore, a parent may wish to purchase a single bow for multiple children having substantially different arm spans, requiring substantially different draw lengths. In each of these scenarios, to significantly change draw length, users must purchase multiple bows or multiple release accessories resulting in a substantial cost, or users must undergo labor-intensive tasks to modify the cams or components of their original bows.
There is a known bowstring release accessory which enables the user to adjust the draw length as a possible alternative to changing bows. This release accessory has a two-part grip, a bar connected to the grip, and a hook connected to the bar. The bar has a fixed quantity of holes used to connect the grip parts to the bar. To set a different draw length, the user must disassemble the two grip parts from the bar, choose a different hole for connecting to the grip parts, and reassemble the grip parts and bar.
This known bowstring release accessory has several disadvantages and problems. The disassembly and reassembly processes are burdensome and cumbersome due, in part, to the need to separate the grip parts and then reunite them. Also, the bar has a fixed and limited quantity of holes permanently formed in the bar. This limitation prevents certain users from making minor, controlled adjustments of the draw length to closely accommodate the users' arm spans. Also, for a user with relatively short arms, for example, the limited quantity of holes may not be sufficient to set the appropriate draw length. Furthermore, the hole arrangement causes looseness within the release. This is because this release has a fastener which is inserted into the selected hole. There is a gap between the fastener's diameter and the hole's diameter. This gap, which extends along the shooting axis, creates internal looseness. In the transition from pre-release to release, the fastener can move within this gap. This movement can decreases the responsiveness and sensitivity of this release accessory, and it can cause a ratchety or jerky operation of this release accessory. These shortcomings can hinder the user's control of this known release accessory and can also impair the user's shooting performance.
Furthermore, the known bowstring release accessories are not designed to provide user-friendly ways to adjust the release sensitivity in a micro-controlled fashion.
The foregoing background describes some, but not necessarily all, of the problems, disadvantages and challenges related to accommodating draw length variations in archery and adjusting the release sensitivity of archery releases. | {
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1. Field of Invention
The present invention relates generally to the field of child learning tools. More specifically, the present invention is related to an educational chair.
Part of growing up for a child is learning the practical things of getting dressed and ready for school, learning how to keep clothes neatly organized, and learn from instructions of parents. Many parents see these tasks as a necessary part of raising the child, but do not have a way to motivate the child to enjoy learning while he or she is growing up. Children often play with dolls, heroes, and cartoon or action figures and enjoy seeing these displayed on items of clothing, toiletries, bedspreads, and school supplies.
2. Discussion of Prior Art
The prior art is replete with examples of learning tools for early education. Typically, these tools are directed to using animated characters, color and/or sound to teach younger children the basics with respect to speaking, walking and later, school related elements such as reading, writing and math.
A child""s chair is also known as evidenced by U.S. Pat. Nos. 4,586,747; 5,354,118; 5,507,551; 4,909,573; 5,941,599; D276,361; D410,795; D356,449; D265,440; and D206,710. Typically, these devices are used to support a child (e.g., car seat, booster seat, or high chair). Animated or facsimile shapes of characters (e.g., bears) are used to make the child more accepting of the chair itself. In some cases, the chair may provide additional learning features such as toilet training (D276,361) or telling time (D410,795). However, the prior art has failed to provide for a chair that teaches the basic skills needed in day-to-day routines (e.g., getting dressed) associated with a younger child.
Whatever the precise merits, features and advantages of the above cited references, none of them achieve or fulfills the purposes of the present invention.
This invention relates to a learning device for children in the form of a child""s chair. This device helps to teach a child various important tools for life, such as how to tell the time of day and the days of the week, how to organize a wardrobe and other objects into compartments, communicate in writing, and vocabulary.
The present invention chair acts as a storage and organizational unit for various articles of children""s clothing. The chair saves parents time in the morning getting a child ready for school. A child may learn vocabulary and how to prepare his or her wardrobe with various hooks, bars, and areas of the chair that correspond to placement of wardrobe items. For example, the back of the chair has bars and hooks to hold a child""s pants, shirt, or dress. The xe2x80x9cshoesxe2x80x9d on the front of the chair are actually hollow compartments wherein the child""s left and right shoes are stored. The child may prepare his or her wardrobe for the following day on the chair, with or without the help of a parent, prior to going to sleep.
The chair is meant to be more than a learning tool for children, it is meant to become the child""s daily xe2x80x9cbuddyxe2x80x9d and a communication tool between the parent and the child. The chair may have the ability to speak to a child through recorded messages set by an alarm clock. Messages may include pre-recorded personal announcements using the child""s name, such as announcements for time to wake up and get dressed, go to school, go to bed, take a bath, etc.
The learning chair has bodily features of fictional characters. The character portrayed by the chair is varied for the interest of the child, such as a boy""s or girl""s doll, action figure, cartoon, or robot visage. The face located on the top of the chair is adjustable in the appearance of mood. A child may express different feelings by changing the mood of the face to angry, silly, happy, or sad. The front of the chair""s back has a magnetic chalkboard for the parents and child to write messages to one another. All of these items are avenues of communication for the child to express and control emotions, exchange messages and receive regular instructions in a personalized and fun medium.
Parents can help place lettering on the front of the chair spelling out the child""s name, or a name given to the chair by a child. Lettering may also be placed on the chair to designate places to store items on hooks or in drawers and compartments.
The learning chair may be constructed of lightweight molded plastic material with sufficient strength to support a range of child""s weights with an appropriate safety factor built in. An alternative chair may also be constructed of wood with similar hollowed compartments, clothes hooks, and amenities built onto the chair. The face and name on the chair may be carved into the wooden chair instead of applied with labels. Other materials, such as metal or stone, or various combinations of any materials sturdy enough to form a chair, may be used in construction of a learning chair. | {
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Greyscale flat bed digital scanners are well known to the art. One such scanner using a charge coupled device (CCD) sensor is illustrated and described, for example, in U.S. Pat. No. 4,500,197. Such apparatus optically scans documents on which data is imprinted on reflective media. The documents are placed face down on a transparent top and are optically scanned by a scanner located within the apparatus under the transparent top. The resulting data is digitized in the prior art apparatus and computer processed for transmission, for example, over telephone lines.
The prior art flat bed digital scanners use light sensitive detectors to measure the reflected light level from the scanned document, such as a photograph, printed matter, magazine page, or the like. Such light sensitive detectors use a technology known as Charge Couple Device (CCD), and serve to quantitize the data in a format suitable for computer processing to be reproduced by peripheral equipment such as a monitor and/or printer, or to be transmitted to remote locations over the telephone lines by appropriate MODEMs.
As mentioned above, the prior art flat bed scanners operate in conjunction with reflective opaque media and the prior art scanners operate by directing an optical beam to the under surface of such media to be reflected by the data imprinted thereon.
The present invention provides an assembly which may be removably mounted on a prior art flat bed scanner to enable the scanner additionally to process data imprinted on transparent media, such as X-ray films. This concept enables inexpensive flat bed digital scanners to be used to scan and digitize data on X-ray films for local reproduction and/or for transmission to remote points.
It has been usual in the prior art to digitize X-ray films by relatively complex and expensive equipment. Such equipment uses photosensitive detectors and precision positioning mechanisms to provide a wide dynamic range of optical density (greyscale) and to maintain accurate spacial representation.
As mentioned above, the present invention enables low cost digitizing flat bed scanners to be used for the same purpose as the more expensive prior art equipment described in the preceding paragraph. As will be described, such low cost flat bed digital scanners may be constructed to perform transparency digitization and to provide an optical density dynamic range greater than the prior art CCD technology used in the more expensive prior art machines will allow.
The optical scanner utilized in the apparatus of the invention is a charge coupled device (CCD sensor) which is used in place of the more bulky conventional optics found in other prior art document scanners. The prior art has typically demonstrated the use of the combination of lens optics and mirrors in order to achieve translation of the image of an illuminated object placed on a document platen glass to an imaging station where the image is exposed into a sensitized photoconductor.
The application and use of the CCD sensor as a scanner provides a way to reduce dimensional space requirements taken up previously by prior art optical scanning apparatus, because of the relatively small size of the CCD sensor assembly. The means of reducing the scanner size is demonstrated in the system described in U.S. Pat. No. 4,500,197. The system of the invention, when combined with other new electronic technology, allows the image of the source material to be processed and developed in different efficient ways. For example, the resultant image may be converted into a train of electronic pulses which are reconstructed on the screen of a cathode-ray tube which may be remotely situated. The images may then be projected directly onto a photoconductor surface where conventional copier processes are used for image development and for transfer of the image onto copy paper.
A typical CCD scanner is partially comprised of a scanner assembly having an optical path with dual mirrors which are arranged compactly so that multiple reflections are generated between the two mirrors. There may be typically six reflections of an image between the two mirrors which necessitates maintaining a strict unyieldable structural relationship between the two mirrors. The need for a rigid vibration-free relationship between the CCD scanner and the mirrors becomes especially critical during translating motion of the scanner carriage.
A solution of certain problems relating to obtaining a direct illuminated image by adjusting the CCD lens unit to the cooperating, compactly arranged mirrors, without physically adjusting the mirrors has been demonstrated in the prior art. Avoidance of disturbing this particular mirror arrangement is highly desirable because of the inherent difficulty in aligning and rigidly holding mirrors designed and intended to generate multiple reflections. These difficulties are greatly compounded because of the mounting of the mirrors in a carriage which is slidably mounted on rails and supported in structure comprising the framework of a machine which has other mechanisms additionally mounted to such framework thereby causing various vibrations or shocks which could adversely affect the reproduction of an image.
An objective of the present invention is to enable a conventional prior art flat bed greyscale and color digitizing scanner to retain its normal feature of digitizing data imprinted on reflective medium by providing a mechanism that will allow the detector electronics of the scanner to recalibrate the mechanism for use in conjunction with X-ray transparencies and the like. It is the nature of the photosensitive detector charge coupled device (CCD) that each detector must be calibrated prior to use. This is due in part to the imperfect nature of the manufacturing process for each detector cell that contributes to an uncertain output.
To overcome the above-mentioned drawback, a common technique in the prior art is to stimulate the detectors prior to scanning with a different reference source. This reference source in the prior art reflective-type scanners is in the form of a white strip that uniformly reflects the excitation light to the detector electronics such that the CCD output can be measured. This measurement then becomes an equalizing reference and establishes the compensation value for the CCD array of detector cells during normal operation of the scanner in conjunction with reflective type media.
The present invention provides an additional reference strip which is used in a second mode of operation of the scanner during which it is processing data on transparent media, such as X-ray films, so as to calibrate the CCD array prior to scanning X-ray films or other transparencies.
Another objective of the invention is to provide a system for use in the conventional CCD detector based flat bed scanner to achieve greater optical density sensitivity dynamic range by improving the detector electronics so as to provide programmable photon integration periods. Such system provides dynamic control of the detector exposure time to enable the CCD to achieve a wider range of sensitivity and thereby significantly improve performance. | {
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Conventionally, so called TN mode liquid crystal displays are largely used in which a liquid crystal having positive dielectric anisotropy is twisted homogeneous aligned between substrates opposed to each other. In the TN mode, however, the liquid crystal molecule in the vicinity of the substrate can cause birefringence due to the driving characteristics so that light leakage can occur, which makes perfect black viewing difficult. While, an in-plane switching-mode liquid crystal display presents a pixel display in a way such that an electric field in parallel with a liquid crystal substrate is formed between pixel electrodes and a common electrode. The liquid crystal display of this type has an advantage, which makes perfect black viewing, which a wide viewing angle is obtained as compared with a TN mode type liquid crystal display in which a vertical electric field to a substrate is formed.
In conventional in-plane switching-mode active matrix liquid crystal display, however, an almost perfect black viewing can be achieved in a direction normal to a panel, whereas in a case where the panel is viewed in a direction deviated from the direction normal to the panel, there has been remained a problem that unavoidable light leakage as a characteristic of a polarizing plate occurs in a direction deviated from the optical axis of the polarizing plates disposed on the top or bottom of a liquid crystal cell with the result is that a viewing angle is narrowed and a contrast is reduced. In another case where the panel is viewed in a direction oblique relative thereto, an optical path of light is longer, which alters an apparent retardation in a liquid crystal layer. Therefore, when viewed at different viewing angles, a wavelength of transmitted light varies, a color of a screen image changes, thereby causing a color shift depending on an observation direction.
Various kinds of proposals have been offered in order to improve reduction in contrast and a color shift depending on a viewing angle in such conventional in-plane switching-mode liquid crystal display(Japanese Patent Application Laid-Open (JP-A) No. 11-133408, JP-A No. 2001-242462). For example, in JP-A No. 11-133408, a proposal has been offered on a technique that compensation layers each with an optical anisotropy are inserted between a liquid crystal layer and respective polarizing plates in pair sandwiching the liquid crystal layer therebetween. This technique is effective for a color shift, but cannot sufficiently suppress a reduction in contrast. In JP-A No. 2001-242462, another proposal has been offered on a technique that first and second retardation plates are inserted between a liquid crystal layer and respective polarizing plates in pair sandwiching the layer therebetween. While it is described in the publication that this technique is effective for improvement on reduction in contrast and color shift, a higher improvement effect has been still desired. | {
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The existing display terminal use hard screens more widely. With the appearance of flexible displays, a mobile phone with a flexible display appears, and the prior art is as follows:
A flexible mobile phone, CN101924816B, comprising: a flexible body, the flexible body comprises a call system, the call system is disposed inside the flexible body; and a flexible display, the flexible display is disposed on the surface of the flexible body; wherein the flexible mobile phone further comprises a flexible touch display disposed on the surface of the flexible display, the flexible touch display comprising at least one transparent conductive layer, the transparent conductive layer comprising a carbon nanotube layer. The flexible mobile phone provided by the embodiment of the present invention has the following advantages: the flexible mobile phone of the present invention uses a carbon nanotube layer as a transparent conductive layer of the touch display, and the carbon nanotube layer has excellent mechanical properties, such as good flexibility and bending resistance, which makes the flexibility and bending resistance of the entire flexible phone improved.
A portable flexible mobile phone, CN107370852A, discloses a portable flexible mobile phone for solving the problem that the flexible mobile phone maintains an annular shape after being bent. In the method of the embodiment of the present invention, when the main body of the mobile phone is in a straight state, the first fixing plug of the connecting rod is movably connected with the first positioning hole of the main body of the mobile phone, and the second fixing plug of the connecting rod fits with the interference of the second positioning hole of the main body of the mobile phone. The first connecting plug of the connecting rod can be movably connected to the first positioning hole, and the second fixed plug has an interference fit with the second positioning hole, so that the main body of the mobile phone is kept in a curved state, the structure is simple, the carrying is convenient, and the hardware cost is low. At the same time, the flexible mobile phone further comprises a flexible outer casing, which can prevent the mobile phone from being damaged when the mobile phone collides or rubs against an external object.
A wristband type multifunctional flexible mobile phone. CN203119972U, the wristband type multifunctional flexible mobile phone of the utility model comprises: a flexible display, a rubber casing, an airbag, a flexible printed circuit board, a back plate, a battery pack, a non-reducible curved hard shell I, a non-reducible curved hard shell II and a processor; the flexible display is arranged in front of the rubber shell, the back plate is arranged behind the rubber shell, and the airbag, the flexible circuit board and the battery pack are arranged in the rubber shell. One end of the rubber shell is provided with a non-reducible curved hard shell I, the other end of the rubber shell is provided with a non-reducible curved hard shell II. And the processor is arranged in the non-reducible curved hard shell I and the non-reducible curved hard case II; the processor is connected to the flexible display and the battery pack through the flexible circuit board, and the battery pack is embedded in the card slot of the rubber shell. The inflatable flexible display is made of AMOLED flexible material, and the back plate is a structure of an electronic ink screen, an AMOLED flexible display or a decorative surface. The battery pack uses a FLCB flexible battery or a flexible zinc battery. An adapter and a headphone interface are arranged on the non-reducible curved hard shell I; the non-reducible curved hard shell II is provided with an earpiece, a camera, a data line interface and a main switch. The wristband type multifunctional flexible mobile phone of the utility model has the characteristics of simple structure, reasonable design, beautiful appearance, portability and multi-purpose. When the hand strap state is present, the outer side can display important information and decorative feature, as well as function with quick operation, or a decorative surface carrying the jewelry design, can better reflect the characteristics of intelligence and jewelry. At the same time, it can replace traditional watches.
In the prior art, the application of the flexible display adopts a structure of full flexible display, and the shape of most of the existing smart phones are right angle quadrilateral. If the right angle quadrilateral phone is worn directly on the wrist to the forearm, the phone is on the same line as the wrist and forearm. From the basic structure of the human body, when the mobile phone is placed directly in front of the user's line of sight, the comfortable angle of the wrist to the forearm and the shoulders of the human body is usually between 15 and 75 degrees (FIG. 1), so whether the mobile phone is straight or put it horizontally on the wrist to the forearm. The straight line between the mobile phone and the “wrist/forearm” and the shoulder line form a slope of 15-75 degrees, which causes the phone to be placed obliquely in front of the user. A mobile phone that is placed obliquely will naturally have many problems in use, such as inconvenient reading. It is not comfortable to put the wrist and forearm in line with the user's front by turning the elbow (FIG. 2). Long-term use can cause the user's “wrist/arm” to be easily fatigued, joint strain and the like. | {
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Current product trends in electronics are requiring flexible circuits of finer and finer pitch. A repeating defect caused by small particles that adhere to a phototool during the imaging step of the flexible circuit making process may significantly reduce the product yield.
The fabrication of flexible circuits involves the creation of several layers of dielectric and conductive materials that are in intimate contact with layers adjacent to them. At least one of these layers may be patterned by selectively introducing material into or removing material from that layer. The pattern may be created by photolithographic processes. For example, a layer of photoresist material is applied onto the surface of the layer to be patterned. A phototool having transparent and opaque areas in the form of the desired pattern is used to selectively expose the photoresist to ultraviolet light. The light will either cause portions of the photoresist to undergo a crosslinking reaction in the exposed areas as in the case of a negative photoresist or will undergo reaction to break down the polymer structure in the exposed areas as is the case with a positive photoresist. The desired portion of the photoresist may be removed by an appropriate solvent. The exposed underlying area may be etched away in the case of subtractive processing or added to in the case of additive processing. In either case the layer is patterned.
Photolithographic processes enable the creation of flexible circuits having excellent feature resolution as well as allowing high throughput of the manufacturing process. If different patterns are applied to different layers, the phototool must be correctly aligned on the photoresist layer. The phototool may be secured to the photoresist by clamping or vacuum when the phototool is placed in contact with the photoresist during this photolithographic process.
However, defects in the pattern or the phototool are routinely experienced, especially when the phototool is used repeatedly to print several substrates consecutively without cleaning the phototool. Consequently, phototools must be inspected and cleaned regularly. This greatly affects the throughput of the lithographic process as well as introducing added cost if the defects cannot be eliminated and the phototools must be replaced.
Conventional phototools often comprise chrome and glass regions. The light passes through the glass regions but not the chrome regions. Both glass and chrome are high surface energy materials, which can cause particles of the photoresist or dust to adhere to the phototool. When particles stick to the glass, light is absorbed and as a result does not reach the photoresist. This can result in inadequate exposure of a given area, which in turn creates defects. Furthermore, particles that adhere to the phototool can create a gap between the phototool and the photoresist surface, reducing resolution of the resulting image. | {
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A phosphor layer is widely used in lamps such as rare gas lamps and fluorescent lamps, and light emitting elements for displays such as PDPs. Among these, rare gas lamps and PDPs are vacuum ultra-violet radiation excited light emitting elements, which are elements that emit light when phosphor layers are irradiated with vacuum ultra-violet rays.
In a PDP, the phosphor layer is produced by applying a phosphor paste on surfaces of a back plate or a baffle by screen printing, direct spraying utilizing a nozzle (dispense method), or the like, followed by drying and baking.
Generally, a PDP has a configuration as described in JP 10(1998)-142781A. Two glass substrates are provided in parallel facing each other, between which interposed are a multiplicity of discharge spaces (hereinafter referred to as “cells”) which are divided by baffles and in which rare gas composed of Ne or Xe as a principal component is capsulated. Among the two glass substrates, one glass plate on the observer side of the PDP is a front plate, and the other glass plate is a back plate. On a back side of the front plate, electrodes are provided, which are covered with a dielectric layer. On the dielectric layer, a protective film (MgO layer) is formed. On a front side of the glass substrate as the back plate, address electrodes are formed so as to cross the electrodes provided on the front plate as described above. Further, a phosphor layer is provided so as to cover a surface of the back plate (corresponding to bottom surfaces of the cells) and surfaces of the baffles. With vacuum ultra-violet rays generated by applying an alternating voltage across electrodes, the phosphor layer is caused to emit light, so that the observer views visible rays that transmit the front plate.
An example of the vacuum ultra-violet radiation excited light emitting element other than the PDP is a rare gas lamp as an illuminating lamp. The rare gas lamp has a configuration similar to the PDP except that the discharge space is not divided by a multiplicity of baffles in many cases. The rare gas lamp attracts attentions from the viewpoint of environment preservation since it does not use mercury, unlike the fluorescent lamp.
The conventional vacuum ultra-violet radiation excited light emitting element such as a PDP or a rare gas lamp does not have a sufficient luminescence, and a vacuum ultra-violet radiation excited light emitting element having a higher luminance and a phosphor layer having a higher luminance for use therein are desired.
An object of the present inventions to provide a phosphor layer having a high luminance and a vacuum ultra-violet radiation excited light emitting element utilizing the same. | {
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1. Field of the Invention
The present invention relates to multi-processor computer systems and, more particularly, to the processing of memory access requests within a multi-processor computer system.
2. Description of the Related Art
Although computation speeds of conventional processors have increased dramatically, there is still a need for even faster computing. Large computational problems such as weather forecasting, fusion modeling, and aircraft simulation demand substantial computing power, far in excess of what can currently be supplied. While processor speed is improving as device speeds increase, the achieved performance levels are still inadequate to handle computationally complex problems.
To achieve high performance computing, a plurality of individual processors have been interconnected to form a multiprocessor computer system capable of providing parallel processing.
In a multiprocessor computing system, there are two sources of delay in satisfying processor memory requests. The first source of delay is the access time to the main memory, and the second source of delay is the communications delays imposed by an interconnection network that connects the various processors. If the bandwidth of the interconnection network is inadequate, the communication delays are greatly increased due to contention for the bandwidth.
One suggested solution to both the bandwidth and access time limitations of interconnection networks is the use of private caches memories at the individual processors. By properly selecting cache parameters, both the transfer ratios (the ratio of memory requests passed on to the main memory from the cache to initial requests made of the cache) and effective access times can be reduced. Unfortunately, private caches introduce a stale data problem (or multicache coherency problem) due to the multiple copies of main memory locations which may be present.
Another suggested solution involves the use of coherency directories. Coherency directories are generally large, separate blocks of memory which keep track of which processor in the multiprocessor computer system owns which lines of memory. Unfortunately, coherency directories can be expensive since additional memory is required and slow since coherency directories are typically structured in a table lookup format. Coherency directories can also severely degrade overall system performance since a memory call must be initiated for every address request.
More recently, shared memory multiprocessing system have interconnected processors (or groups of processors) by a single bus (e.g., an address bus). Unfortunately, as the processor speeds increase, the feasible number of processors that can be connected through a single bus decreases. One problem with using a bus is that performance degrades as more devices are added to the bus. This means that the bandwidth of a bus available to a processor actually shrinks as more processors are added to the bus.
FIG. 1A is a block diagram of a portion of a conventional multiprocessor computer system 100 illustrating typical snoop result paths between various processor groups. Computer system 100 includes a first processor group 110, a second processor group 120, a third processor group 130, an address interconnect 150, and a data interconnect 160. It should be noted whereas only three (3) processor groups are shown in FIG. 1, multiprocessor computer system 100 typically includes any suitable number of processor groups. Communication between the processor 110, 120 and 130 are provided by way of bidirectional buses 140 and 142. Each of processor groups 110, 120, and 130 includes a snoop results distributor and an address repeater. The address repeaters are used to communicate with address interconnect 150 by way of bidirectional buses 140 and 142. Generally, address interconnect 150 broadcasts address requests to every address repeater within computer system 100 whereas data interconnect 160 operates as a point to point router.
In operation, processor groups 110, 120 and 130 transmit their respective memory address requests directly to address interconnect 150. Address interconnect 150 will arbitrate any conflicting address requests and will simultaneously broadcast back to all groups of processors (including the original requester group) within system 100 the chosen requested address request. Once received, each processor group will generate and store a group snoop result in its own snoop results distributor. Each group's snoop results distributor will then broadcast to all other snoop results distributors in every processor group in system 100 their respective group snoop result. In this manner, every processor group within computer system 100 obtains the group snoop results of every other processor group. Thereafter, the processor group initiating the address request is directed to the appropriate memory location within the computer system 100. A conventional multiprocessor system utilizing a snoop system having such a snoop results distributor is exemplified by the STARFIRE system manufactured by Sun Microsystems, Inc. of Mountain View, Calif.
FIG. 1B is a flowchart illustrating a typical memory address request transaction in the conventional multiprocessor computer system 100 shown in FIG. 1A.
The conventional multiprocessor computer system memory address request transaction process 150 begins with an individual processor sending 10 an address request to the associated address repeater. As is known to those skilled in the art, at least one processor in a processor group will typically generate an address request to seek a specific block of memory. An address request typically will be associated with a specific memory command indicative of the purpose for which the block of memory is being requested by the processor. The address requester will forward 12 the received address request to the address interconnect associated with conventional multiprocessor computer system 100. The address interconnect, after appropriate conflict arbitration, will broadcast 14 the chosen address request to all address repeaters included within conventional multiprocessor computer system 100, including the address repeater associated with the original requester group of processors. Each associated address repeater will broadcast 16 the received address request to each of its associated individual processors. Each individual processor will in turn query 18 their respective memory cache to determine whether they have owned or shared a copy of the requested memory address. Based on the determining 18, each processor will generate an individual snoop result which is subsequently forwarded 20 to the snoop results distributor associated with the group of processors. The snoop results distributor then combines 22 all individual snoop results received from individual processors to form a group snoop result. The snoop result distributor then broadcasts 24 the group snoop result to all other snoop results distributors within computer system 100 since each snoop results distributor is capable of broadcasting and receiving the group snoop result from all other groups of processors within system 100.
Each snoop result distributor will combine 26 the group snoop results received from all other snoop results distributors within computer system 100 to form a global snoop result. The global snoop result contains all information relating to the ownership of the page of memory associated with the requested memory address for all groups of processors within system 100. Each snoop result distributor will forward 28 the global snoop result to all individual processors within its associated group of processors. Upon receipt of the global snoop result, the original requester processor will obtain 30 the requested page of memory.
As the number of processors added to the computer system increases, the amount of irrelevant data on the address bus degrades overall system performance. By way of example, as more processors are added to the computer system, at some point the maximum address bandwidth precludes any improvement in overall system performance at which no additional performance gained by adding more processors.
Thus, there is a need for techniques to reduce transmission of address requests between various processors in a multiprocessor computer system. | {
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With the development of mobile terminal technologies, the intelligence of a mobile terminal is in great demand. When playing voice data, it is important to reflect the intelligence of the mobile terminal such that the mobile terminal can automatically select a play mode according to an operation of a user. For example, a conventional mobile terminal is provided with an infrared sensor that is set at two sides or in a groove of an earphone of the mobile terminal. When the voice data is played, the infrared sensor transmits an infrared signal to detect a distance between the user and the mobile terminal, specifically a distance between the user and a screen surface of the mobile terminal. If the detected distance is smaller than a preset threshold, the mobile terminal determines that the user puts the mobile terminal closer to the ear of the user, and switches into an earphone play mode thereby using the earphone to output the voice data. If the detected distance is not within the preset threshold, the mobile terminal enters into a speaker play mode, and plays the voice data through the speaker. However, the conventional mobile terminal controls the play mode only through the distance between the user and the mobile terminal and may cause many undesirable operations. For example, if the hand of the user approaches the screen surface of the mobile terminal by accident, or the finger of the user covers the screen surface of the mobile terminal by accident, an unnecessary switchover operation of the play mode is triggered, and thus the accuracy of controlling the play mode is affected, more system resources are wasted, and the intelligence of the mobile terminal is deteriorated. | {
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SST dies are used in a wide variety of products and applications related to emitting and/or sensing radiation. Several types of SST dies that emit electromagnetic radiation in the visible light spectrum are used in mobile phones, personal digital assistants (“PDAs”), digital cameras, MP3 players, computers, tablets, and other portable electronic devices for backlighting and other purposes. SST dies are also used for signage, indoor lighting, outdoor lighting, vehicle lighting, and other types of general illumination.
FIG. 1A is a cross-sectional view of a conventional SST die 10a having lateral configuration. As shown in FIG. 1A, the SST die 10a includes an SST 40 on a growth substrate 17. The SST 40 can be an LED having a transduction structure 30 comprising an active material 15 between layers of N-type GaN 16 and P-type GaN 14. The active material 15 contains gallium nitride/indium gallium nitride (GaN/InGaN) multiple quantum wells (“MQWs”). The SST 40 also includes a P-type contact 18 on the P-type GaN 14 and an N-type contact 19 on the N-type GaN 16. In operation, electrical power provided to the SST die 10a via the P-type and N-type contacts 18 and 19 causes the active material 15 to emit light.
FIG. 1B is a cross-sectional view of another conventional SST die 10b in which the P-type and N-type contacts 18 and 19 are in a vertical configuration. During formation of the SST die 10b, the N-type GaN material 16, active material 15 and P-type GaN material 14 are grown on a growth substrate (not shown in FIG. 1B), which can be similar to the growth substrate 17. After forming the transduction structure 30, a carrier 20 is attached to the P-type contact 18. For example, one side of the P-type contact 18 can be attached to the P-type GaN 14 and the other side of the P-type contact 18 can be attached to the carrier 20 using a bond material 22, which can be composed of metal or metal alloy layers. The bond material can be a Ni—Sn—Ni stack such that one Ni layer contacts the carrier 20 and the other Ni layer contacts the P-type contact 18. Other bond materials, such as CuSn and/or TiSi, can be used. Next, the growth substrate can be removed and the N-type contact 19 can be formed on the N-type GaN 16. The structure is then inverted to produce the orientation shown in FIG. 1B.
Most electronic devices and many other applications require a white light output. However, true white light LEDs are not available because LEDs typically emit light at only one particular wavelength. For human eyes to perceive the color white, a mixture of wavelengths is needed. One conventional technique for emulating white light with LEDs includes depositing a converter material (e.g., a phosphor) on an LED. For example, FIG. 2A shows a conventional lighting device 30a that includes a device substrate 50, an SST die 10a or 10b mounted on the device substrate 50, and a converter material 60 on the SST die 10a-b. The light emitted from the SST 40 undergoes at least partial conversion while passing through the converter material 60 as explained in more detail below with respect to FIG. 2C.
Multiple SST dies 10a-b can be used in a lighting device. For example, FIG. 2B is a cross-sectional view of a conventional multi-SST lighting device 30b having the device substrate 50, a plurality of SST dies 10a-b attached to the device substrate 50, and the converter material 60 over the SST dies 10a-b. The multi-SST lighting device 30b also has a single lens 80 over the SST dies 10a-b. Other conventional multi-SST lighting devices may have a dedicated lens per SST or a group of SSTs. All the SSTs 40 in the multi-SST lighting device 30b are typically connected to a common anode and cathode such that all of the SST dies 10a-b operate together.
FIG. 2C schematically illustrates the light frequency conversion and scattering/reflection in a conventional lighting device 30c in which the lens 80 encloses the SST 40 and the converter material 60. The SST 40 emits blue light (B) that can stimulate the converter material 60 to emit light at a different frequency, e.g., yellow light (Y). Some blue light (B) emitted by the SST 40 passes through the converter material without stimulating the converter material 60. Other blue light (B) emitted by the SST 40 stimulates the converter material 60, which, in turn, emits yellow light (Y). The combination of the emissions of blue light (B) from the SST 40 and the emissions of yellow light (Y) from the converter material 60 is designed to appear white to a human eye if the blue and yellow emissions are matched appropriately. However, not all light emitted by the SST 40 ultimately leaves the lighting device 30c. For instance, the converter material 60 scatters some blue light (B) back toward the SST 40. Additionally, some light that reaches the outer edge of the single lens 80 reflects back toward the converter material 60 and further toward the SST 40.
FIGS. 3A-3C show top views of several conventional lighting devices constructed as schematically illustrated in FIGS. 1B and 2A with different patterns of N-type contacts over the N-type GaN of the SSTs 40. The patterns of N-contacts are designed to distribute electrical current through the N-type GaN to other relevant parts of the SST. Some examples of the N-contact patterns are rail-type N-contacts running within the outline of the SST 40 (FIG. 3A), dot-type N-contacts distributed over the SST 40 (FIG. 3B), and rail-type N-contacts extending beyond the outline of the SST 40 (FIG. 3C). The N-contacts 19 can cover an appreciable percentage of the surface area of the SST 40. Since the N-contacts 19 may absorb a significant portion of the light that is scattered from the converter material, refracted from the lens 80, or reflected from other objects (not shown), the N-contacts 19 are relatively “dark regions” on the surface of the SST that reduce the output. Consequently, even though a particular N-contact layout may improve the distribution of electrical current through the SST 40, conventional N-contacts may impair the visual appearance and reduce the efficiency of the device. | {
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Fletching of an entirely homogeneous blend of polymer materials is known. However, such fletching can be difficult and relatively time consuming to secure to an arrow shaft. In addition, such fletching can have a vane or blade that tends to fold during flight, which can interfere with the true flight of an arrow launched toward a target from a bow.
Therefore, a need exists for improved fletching and to an improved method of manufacturing such fletching. | {
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Wafer bonding (also called wafer fusion) techniques have been extensively practiced for different applications requiring different substrates. These techniques enable two different wafers to be bonded together, so that fabrication of highly lattice-mismatched and orientation-mismatched heterostructures become possible without generating threading dislocations. For example, wafer bonding techniques have been utilized to form silicon-on-oxide (SOI) substrate, and for bonding III–V materials with other materials.
The prior art wafer bonding techniques, however, do not provide for fabricating a hybrid substrate by integrating three or more different types of material on a common carrier substrate. It is desirable to have a system chip which includes mixed devices, such as laser diodes for external communication, rf or microwave high-power, high-frequency devices for transmitting and receiving data, and high density, low-power silicon devices for logic and memory.
As an example, GaN-based high-electron mobility transistors (HEMTs) are known to have high saturation velocity and enhanced mobility in nitride semiconductor heterostructures. Accordingly, they are suitable for high-power applications at microwave frequencies. These devices are typically built on a GaN on sapphire substrate or a SiC substrate.
On the other hand, optoelectronic devices are typically built on a substrate formed by III–V materials. For example, InGaAsP/InP edge-emitting lasers are usually fabricated using InP over a silicon substrate. The bonding process entails first depositing a p-type InP substrate and capping it with a p-type InGaAs film. Second, a n-type InP substrate is deposited over the film. The n-type InP substrate is then bonded to the silicon substrate. The bonded wafer is then annealed at 400 degrees Celsius.
In order to create a sophisticated system, for example, a system having GaN based high-electron mobility-transistors and optoelectronic devices to realize more applications, it is required to integrate such different devices on more than two different substrates. It is therefore required to provide a substrate having multiple materials, i.e., a hybrid substrate, where each material can be used for fabricating one or more different devices. For example, one material can be used for fabricating the GaN based high-electron mobility-transistors, another material can be used for fabricating the optoelectronic devices, and another material can be used for high-density, low-power Si-based devices.
Additionally, by providing a hybrid substrate, chips fabricated from different materials can be fabricated on the hybrid substrate. For example, a first part of the hybrid substrate can be used for fabricating a GaAs chip, a second part of the hybrid substrate can be used for fabricating a InP chip, and a third part of the hybrid substrate can be used for fabricating a silicon chip. | {
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1. Field of the Invention
The present invention relates to a probe cover dispenser, particularly to a dispenser, which can automatically deliver a probe cover to sleeve a probe.
2. Description of the Related Art
When bacteria or viruses invade the body, the immunological reaction most frequently seen is a fever, whereby the body can repair the damage caused by infection. In such a case, the body temperature needs frequently monitoring to learn the status of the body timely. The body temperature is usually measured in some specified regions, such as the mouth, the armpit, the ear and the anus. The ear temperature and the anal temperature are closer to the central temperature of the body. Further, the ear temperature and the anal temperature are easier to detect than the armpit temperature and the oral temperature. Besides, the ear temperature and the anal temperature have more stable measurement results than the armpit temperature and the oral temperature. Therefore, the infrared ear thermometer is a temperature measurement instrument most frequently used nowadays. However, the probe of an infrared ear thermometer is likely to accumulate earwax, which may result in mutual infection among users. Thus, the probe cover needs replacing after each time of use.
Conventionally, the user takes a probe cover to sleeve the probe with his hands. Such an operation is very likely to pollute the probe cover and cause an infection. Therefore, there are some technologies developed to prevent a probe cover from being polluted by hands. A U.S. Pat. No. 4,993,424 disclosed an infrared clinical thermometer having a probe cover storage device and a probe cover delivery device. When the probe is withdrawn into the head of the thermometer, the probe cover can automatically sleeve the probe without using hands. However, the prior-art infrared thermometer is complicated, bulky and expensive, and the ordinary consumers are hard to afford it.
Refer to FIG. 10 for a probe cover dispenser disclosed in a U.S. Pat. No. 5,100,018. The prior-art probe cover dispenser 56 has a body 58. A probe cover storage chamber 60 and a block plate 62 are arranged in the lower portion of the body 58. The probe cover storage chamber 60 stores probe covers stacked one above one, and the block plate 62 controls the delivery of the probe covers. A press plate 64 and a spring 66 are arranged above the probe cover storage chamber 60. The spring 66 adjusts the position of the press plate 64. A slide plate 68 is arranged below the probe cover storage chamber 60. The slide plate 68 has an indentation 70 able to receive a single probe cover. When the slide plate 68 is pushed toward the body 58, the block plate 62 is pushed outward, and the indentation 70 slides to reach a position exactly below the probe cover storage chamber 60 and receive a single probe cover. Then, the slide plate 68 together with the released probe cover is pulled out, and the probe is inserted into the probe cover inside the indentation 70. Thus, the probe is sleeved by the probe cover. However, the conventional probe cover dispenser is complicated, expensive, and hard to popularize. When the probe covers in the probe cover storage chamber 60 decrease, the pressing force that the spring 66 applies on the press plate 64 also decreases. Thus, the force pressing down the probe covers becomes smaller, which may cause the error of delivering the probe cover.
To overcome the abovementioned problems, the present invention proposes a probe cover dispenser, which uses a simple structure to automatically deliver a probe cover. | {
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(a) Field of the Invention
The present invention relates to an apparatus to provide pulses of light. In my parent application, I disclosed a mechanically-pulsed irradiation generation apparatus having a light source and at least one rotating cylinder having slits which allowed a discrete pulse of light to pass therethrough when in proper alignment. In my parent application, I further teach placing the cylinder adjacent to the light source. This configuration results in the majority of the light being wasted when a circumferential omnidirectional radiating light source is employed, as the slits pass only that amount of light radiated toward them. Therefore, I have now invented a much more efficient apparatus to provide the mechanically-pulsed light. This is accomplished by placing at least one hollow cylinder having at least one opening through the cylindrical surface around the light source, and that is the focus of this continuation-in-part application.
(b) Description of the Prior Art
The prior art identified in my parent application is herein incorporated by reference. I have discovered no additional art relevant to my present invention. | {
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The present disclosure relates generally to the inspection of equipment and facilities, and more particularly to borescope systems used for the inspection.
Certain equipment and facilities, such as power generation equipment and facilities, oil and gas equipment and facilities, aircraft equipment and facilities, manufacturing equipment and facilities, and the like, include a plurality of interrelated systems, and processes. For example, power generation plants may include turbine systems and processes for operating and maintaining the turbine systems. Likewise, oil and gas operations may include carbonaceous fuel retrieval systems and processing equipment interconnected via pipelines. Similarly, aircraft systems may include airplanes and maintenance hangars useful in maintaining airworthiness and providing for maintenance support.
Certain techniques, such as non-destructive inspection techniques or non-destructive testing (NDT) techniques, may be used to inspect and facilitate maintenance of such equipment and facilities. For example, a borescope system may be utilized in an NDT technique to inspect the internals without disassembly of a wide variety of equipment and facilities. Specifically, a borescope probe may be inserted into various openings of the equipment or facility to provide illumination and/or visual observations of the internals of the equipment or facility. Accordingly, it would be beneficial to improve the configuration of such borescope systems, for example, to enable a user to more accurately and efficiently adjust settings as desired. | {
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1. Field of the Invention
The present invention pertains to the production, manipulation and exploitation of high electrical charge density entities. More particularly, the present invention relates to high negative electrical charge density entities, generated by electrical discharge production, and which may be utilized in the transfer of electrical energy.
2. Brief Description of Prior Art
Intense plasma discharges, high intensity electron beams and like phenomena have been the subjects of various studies. Vacuum Arcs Theory and Application, Edited by J. M. Lafferty, John Wiley & Sons, 1980, includes a brief history of the study of vacuum discharges, as well as detailed analyses of various features of vacuum arcs in general. Attention has been focused on cathode spots and the erosion of cathodes used in producing discharges, as well as anode spots and structure of the discharges. The structure of electron beams has been described in terms of vortex filaments. Various investigators have obtained evidence for discharge structures from target damage studies of witness plate records formed by the incidence of the discharge upon a plane plate interposed in the electrical path of the discharge between the source and the anode. Pinhole camera apparatus has also disclosed geometric structure indicative of localized dense sources of other radiation, such as X-rays and neutrons, attendant to plasma focus and related discharge phenomena. Examples of anomalous structure in the context of a plasma environment are varied, including lightning, in particular ball lightning, and sparks of any kind, including sparks resulting from the opening or closing of relays under high voltage, or under low voltage with high current flow.
The use of a dielectric member to constrain or guide a high current discharge is known from studies of charged particle beams propagating in close proximity of a dielectric body. In such investigations, the entire particle flux extracted from the source was directed along the dielectric guide. Consequently, the behavior of the particle flux was dominated by characteristics of the gross discharge. As used herein, "gross discharge" means, in part, the electrons, positive ions, negative ions, neutral particles and photons typically included in an electrical discharge. Properties of particular discrete structure present in the discharge are not clearly differentiated from average properties of the gross discharge. In such studies utilizing a dielectric guide. The guide is employed wholly for path constraint purposes. Dielectric guides are utilized in the context of the present invention for the manipulation of high charge density entities as opposed to the gross discharge.
The structure in plasma discharges which has been noted by prior investigators may not reflect the same causal circumstances, nor even the same physical phenomena, pertinent to the present invention. Whereas the high charge density entities of the present invention may be present, if unknown, in various discharges, the present invention discloses an identification of the entities, techniques for generating them, isolating them and manipulating them, and applications for their use. The technology of the present invention defines, at least in part, a new technology with varied applications, including, but not limited to, execution of very fast processes, transfer of energy utilizing miniaturized components, time analysis of other phenomena and spot production of X-rays. | {
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This invention relates to the production of magnetic recording disks and more particularly to a method of smoothing the media to increase the recording capacity of the flexible disk.
U.S. Pat. Nos. 4,874,633 Kasaga et al., 5,804,283 Inaba et al., and 5,851,622 Ejiri et al. relate to a method of producing magnetic recording media used by Fuji Photo Film Co. This process is often referred to as a xe2x80x9cwet on wetxe2x80x9d process. For the typically flexible high density media, the substrate is between 30 and 60 microns thick and has bumps which facilitate the unrolling of the film. The bumps may be one or two microns tall. A planarizing layer is applied to the substrate to cover most of these rough spots. Then the magnetic layer is applied which has particles and binders. One of the last steps in the process is to pass the web of media through rolls in a calendaring process which flattens the web of media. In some instances an attempt is made to burnish the media. However, it is well known that even with calendaring and burnishing the media still has bumps which are quite large in the scale of magnetic recording wherein disparities in the range of 30 nanometers or larger present a problem. If a magnetic recording head hits the disparity this causes the head to ride over the disparity and causes spacing loss preventing effective recording on some areas oft he material.
A continuously running web of media is cut into disks which are referred to as xe2x80x9ccookies.xe2x80x9d The xe2x80x9ccookiesxe2x80x9d cut from the web material are made into flexible magnetic recording disks used in cartridges for flexible media magnetic recording systems such as the ZIP and Clik! storage systems made by Iomega corporation. These recording systems have increasingly higher data capacities. The higher density recording requires an exceptionally smooth recording system.
One of the critical processes in making the cookies into disks for high capacity recording cartridges is laying down servo tracks on the media. This is typically performed by a very expensive machine that has exceptionally good positional accuracy. The machine writes the servo on the information medium by magnetic recording. This takes as long as six to eight minutes. Steps have been taken to spin the disk faster so that the write operation will take less time, but still it is a very expensive procedure to servo write a flexible disk. It has been suggested to print the servo track or stamp the servo track. This is often referred to as xe2x80x9cembossed servoxe2x80x9d. Embossed servo techniques are described in the following references: IBM TDB vol. 21, No. 10, xe2x80x9cFloppy Disc Embossing for Servo Applications,xe2x80x9d Acosta et al., 3/79 pp.4259-4260; xe2x80x9cEmbossed Servo Techniques for Floppy Discsxe2x80x9d, Thompson, et al., 1979, pp. 321-327; U.S. Pat. No. 4,935,835, Goodwin, et al., 4,958,425, Roth, et al.; 5,067,039 Godwin, et al.; 5,535,069, Chiao, et al.
It is an object of the present invention to smooth or flatten recording media for increased capacity flexible disk magnetic recording systems.
In accordance with the invention a magnetic recording disk is smoothed by positioning the disk between flat plates and increasing the temperature and pressure on the disk. Pressure is increased until the pressure approaches the yield strength of the substrate of the disk. Temperature is increased to above the glass transition temperature of the substrate, thereby allowing local deformation with low residual stress.
Further in accordance with the invention, one of the flat polished plates may be engraved with a servo pattern. When the disk is pressed between the flat plates, servo tracks are embossed on the media. The plates compress the media locally and plastically deform it. The disk is then passed through a magnetic field. The spacing over the embossed holes is so great that there is no magnetic signal in selected areas. This produces a magnetic servo track in an efficient manner.
The foregoing and other objects, features and advantages of the invention will be better understood from the following more detailed description and appended claims. | {
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Polarization independent devices such as optical circulators and isolators generally require separating the input beam having an unknown polarization state, into two orthogonally polarized sub-beams. These sub-beams are routed through the isolating elements of the device such as reciprocal and non-reciprocal rotators and are combined at an output end. However, if the beams are launched in a backwards direction non-reciprocal elements ensure that the light does not couple back into the input port. Rutile crystals, and other birefringent crystals are well known for the purpose of separating an input beam into two orthogonally polarized sub-beams thereby serving as a polarization beam splitter, or operated in an opposite direction as a polarization beam combiner. Within this specification the term polarization beam splitter is used however it should be understood, that the same device serves as a polarization beam combiner operated in reverse.
It has been typical, for light propagating within these crystals to be collimated, most often by a graded index (GRIN) lens. In this instance a relatively large crystal is required to ensure separation of two beams that have diameters typically as large as 350 μm. However, recently, it was discovered that very small crystals, about 1/50th the size of conventional crystals could be used with a non-collimated beam; using such small crystals substantially lessens the cost of manufacturing optical splitters/combiners, circulators or optical isolators.
A polarization beam combiner joins light from different inputs into one common port. This is commonly required, for example, for combining pump power from one or more lasers with an optical signal into an optical amplifier. A polarization splitter splits a beam of light into two sub-beams of orthogonal polarization components directed to two separate outputs. It is desired to provide isolation to prevent light from coupling back into the input port of the splitter. This is generally done by providing an external isolator, a pigtailing of polarization maintaining fiber, and a separate splitter.
Isolation for the combiner is more critical, as light coupled back to the laser source will cause damage to the laser. An external isolator is provided between the lasers and the combiner. However, laser pump power is expensive to provide, and using a separate isolator and combiner increases insertion losses.
It is an object of the present invention to provide a combiner, which can provide the isolation function and increase pump coupling efficiency. It is a further object to provide a smaller, more cost effective isolated polarization splitter/combiner using fewer parts and less polarization maintaining fiber.
A further disadvantage of prior art object space polarization beam splitters/combiners is that there is a difference in optical path length for the two separated orthogonal polarizations traveling through a birefringent crystal. Using birefringent crystals where the light propagating therethrough is not collimated, leads to an increase in insertion loss due to a defocusing or a need to compensate for the path length difference. The sub-beams follow a slow axis (extraordinary), and a fast axis (ordinary), which correspond to this difference in optical path length. It is typical after separating the beam into its two orthogonal polarization states through a rutile crystal to couple the light into two fiber ends. However, the two focus spots from the crystal do not lie on a same focal plane. This is due to the optical path length difference for the e-ray and the o-ray through the crystal. Generally pairs of optical fibers are held securely in a fixed manner in an optical fiber tube. If a tube is used to couple light from the crystal aligned at the focus spot of one of the beams, the other focus spot will not be in focus at the tube end, and light from either the e-ray or o-ray path will couple poorly.
It is a further object of this invention to provide an isolated beam splitter/combiner which lessens or obviates this optical path length difference, having substantially same optical path lengths for two split or combined beams propagating therethrough. | {
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1. Field of Invention
This invention is concerned with apparatus for producing inphase (I) and quadrature (Q) components of a modulated baseband input signal, and more particularly, with such apparatus utilizing digital techniques.
2. Description of the Prior Art
In many radar, sonar, and communication systems, product detectors are used to demodulate a radio frequency (RF) or an intermediate frequency (IF) signal into its inphase and quadrature components at baseband. These I and Q components, as they are commonly called, are then sampled for subsequent processing. Conventionally, the demodulation and sampling are performed using two mixers (90.degree. out of phase relative to one another), appropriate low pass filters, and analog-to-digital converters. If, however, the characteristics of the components in the two branches or channels (I and Q) are not precisely matched, distortions will result. The distortions may severely affect the performance of the overall system. | {
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1. Field of the Invention
The invention relates to a light-emitting diode (LED) chip and more particularly to a white-light LED chip and a fabrication method thereof.
2. Description of the Related Art
Light-emitting diode (LED) is a compound semiconductor device that energy transfers electrical current into light. The light emitted by an LED is distributed across a spectrum that is approximately 20˜40 nm wide and has a peak emission wavelength defined by the semiconductor material of a light-emitting layer of the LED. As a consequence of the peak emission wavelength, a single LED cannot emit white light, which is composed of spectral contributions from almost the entire wavelength range of the visible spectrum. FIG. 1 shows a cross section of a conventional white light emitting device 100. The white light emitting device 100 includes a blue-light LED chip 12 disposed in a reflective cup 10 and surrounded by phosphors 14. A glass plate 16 is disposed on the reflective cup 10, covering the LED chip 12 and the phosphors 14. In the exemplary device of FIG. 1, a portion of the blue light emitted by the LED chip 12, and the red and the green light emitted by the phosphor 14 as a result of a partial absorption of the blue light can combined to produce white light.
However, white light generated by sources such as the device illustrated in FIG. 1 is not uniform in color. This non-uniformity is a consequence of the variations in the thickness of the phosphors 14 surrounding the LED chip 12. The variations in the thickness cause spatially non-uniform absorption of blue light and emission of red and green light. Therefore, the generated white light is surrounded by colored rings.
U.S. Pat. No. 6,576,488 discloses a method for conformally coating a light emitting semiconductor structure, such as an LED chip, with a phosphor layer. The method involves electrically coupling an LED chip to a submount, applying a first bias voltage to the submount, and applying a second bias voltage to a solution of charged (pumped) phosphor particles. The electric field created by the two bias voltages induces the phosphor particles to deposit on the conductive surface, such as the surfaces of the submount and the LED chip. However, using the electrophoretic deposition process to form a phosphor layer on a LED chip has some problems. The adhesion between the phosphor particles and the surface of the LED chip is weak, such that the phosphor layer is easily separated from the LED chip. U.S. Pat. No. 6,576,488 discloses using a chemical vapor deposition (CVD) process to form a tinted thin film of a yellow color material on a blue LED element. This method can improve light uniformity and the light output is not heavily dependent on the thickness of a substrate of an LED chip. However, the process of this method is complicated, as passivation layers that cover the LED chip need to be formed. Additionally, it is difficult to control the process for forming the tinted thin film of the yellow color material on the LED chip by the CVD process.
Therefore, a white-light LED chip with uniformity in color that is capable of overcoming the above problems is desired. | {
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Controlling matter within nanochannels at atomic scale resolution is crucial for a wide variety of applications, including desalination devices and other types of chemical separations, deposition of quantum dots and molecule-by-molecule deposition, in general, of organic and inorganic molecules, fabrication of nanoscale devices at molecular resolution, precise DNA recording, precision movement of DNA and other biopolymers and other polymers, control of chemical reactions molecule-by-molecule, angstrom-scale movement of macroscale objects, and enabling new interactions between molecules within nanochannels and external particles or polarons, excitons or other types of quasiparticles. Flow through nanochannels is a crucial component of a wide variety of applications for which tunable transport properties are advantageous. For example, flow through nanochannels is a crucial component of a wide variety of applications for which a molecule from a solution is selectively transported with low energy input.
Nanoscale channels are not simply miniaturized microscale channels. However, in prior art methodologies, the transport is assumed continuous as in a pipe, and can not be discretely metered by the attributes of the nanochannel and transported molecules. In conventional methodologies, the substance being transported is treated as having a homogeneous density along the nanochannel.
In the conventional treatment of a single-file of molecules, the prediction in some cases is that there would be no transport, as predicted by the no-slip boundary condition. In other cases, in which a slip coefficient is introduced, the transport, at each instant in time, is constant at each cross section.
The delivery of large molecules by flow external to the nanotube has been numerically simulated (Patra and Král, J. Am Chem. Soc. 133: 6146 (2011), while the transport of charged molecules on the outside of nanotubes has been numerically simulated (Král and Wang, Chem. Rev. 113: 3372 (2013)).
Prior fabricated nanochannel devices have employed nanochannels with of a width where several of the atoms or molecules that enter the channels can fit within the cross section of the nanochannel. In contrast, reports of partially filled narrow nanochannels, for example (5, 3) carbon nanotubes, are relatively recent (Qin et al., Nano Lett. 11:5 (2011); Cambre et al., Phys. Rev. Lett. 104:20 (2010)).
While bulk water freezes near 0 degrees C. at standard pressure (1 atm), water within narrow carbon nanotubes is observed in numerical simulation in a solid-like state at higher temperatures (Wang et al., Science 322:5898 (2008)). The structure of contained frozen water is thought to depend on channel diameter. Wang et al. do not consider transport through nanochannels.
In prior art computer simulations, short single-file nanochannels are simulated being used for desalination (Corry, J Phys. Chem. B 112:5 (2008), Kalra, Garde and Hummer, Proc. Natl. Acad. Sci. USA 100: 10175 (2003)). In fluids applications, such as lab-on-a-chip devices, conventional methodologies suggest that channel lengths should be minimized to reduce power requirements. Additionally, in prior art channels wider than those for single-file flow are used for desalination. The use of wider channels is thought to always increase the volumetric flow rates of water. Molecular groups at the channel entryway hinder the entry of ions into the large channels (Majumder et al., J. Memb. Sci. 316:1-2 (2008)). There, wide channels are used to increase the volumetric flow rates of water. In prior art, nanochannels are modeled as pipes (Majumder et al., Nature 438:7064 (2005); Holt et al., Science 312:5776 (2006)).
In prior art, single-file substances within nanochannels are assumed to be essentially incompressible. In some prior simulations and theoretical models (Berezhkovsky and Hummer, Phys. Rev. Lett. 89:6 (2002); Zhu et al., Biophys. J. 85:1 (2003)), contained substances span the full length of single-file nanochannels and are treated as an incompressible rod. References are made to the collective motion of the particles and “collectivity”, as is appropriate for rod-like motion. In other treatments (Chou, Phys. Rev. Lett. 80:1 (1998)), the atoms or molecules making up the contained substance occupy discrete sites within the nanochannel, or such sites may be unfilled. Thus, contained substances form contiguous incompressible segments spanning sequentially filled sites, which are separated from each other by any number of discrete contiguous vacancies. Contiguous segments are rod-like and the spacing between neighboring substance particles is uniform.
In conventional methodologies, it is considered to be desirable to decrease the roughness in order to increase flow. U.S. Pat. No. 7,341,651 B2 (2008) to Regan et al. proposed to use an electric field to move molecules along a carbon nanotube; however, the carbon nanotube of Regan et al. does not include precise and controllable step-like advance. Regan et al. state that the transport occurs “without the atoms (or clusters of atoms) being . . . stuck on the channel.” For materials that are solid at the operating temperature, Regan et al. propose a means to heat the material, and state “it is necessary that the channel be sufficiently warm to permit atomic movement”. Thus heating is considered advantageous. The device of Regan et al. is limited to charged molecular materials.
Ghosh et al., Science 299:1042 (2003) investigated the flow of water past a bundle of carbon nanotubes and speculated that there is a coupling between the induced voltage and the external classical Poiseuille flow. The generation of a voltage difference in a 1.6 nm carbon nanotube on application of a current in the presence of external water vapor was investigated by Zhao et al., Adv. Mat. 20:1772 (2008).
There is a need to more advantageously provide means to control, adjust, and tune the flux of water or other atoms, molecules, ions, electrons, or other types of particles, through nanochannels. Nanochannels may be used to transport substances while excluding other substances. The ability of nanochannels to allow passage of particular substances while excluding others, is the basis for a variety of applications. For example, water can be allowed passage while excluding sodium, chlorine and other ions, and so these types of nanochannels can be used for desalination. | {
"pile_set_name": "USPTO Backgrounds"
} |
This invention relates to certain metallocenies. In another aspect this invention relates to the polymerization of olefins. In another aspect this invention relates to metallocene based catalyst systems for the polymerization of olefins.
The discovery that metallocenes of transition metals can be used as catalysts for the polymerization of olefins has led to significant amounts of research since it was found that different metallocenes could produce different types of polymers. One of the earliest references to the use of metallocenes in the polymerization of olefins is U.S. Pat. No. 2,827,446 which discloses a homogeneous, i.e. liquid, catalyst system of bis(cyclopentadienyl)titanium dichloride and an alkyl aluminum compound. The activity of such systems was not, however, as high as would be desired. It was latter discovered that more active catalyst systems would result if the metallocene was employed with an alkylaluminoxane cocatalyst, such as that disclosed in U.S. Pat. No. 3,242,099.
U.S. Pat. Nos. 5,498,581 and 5,565,592 revealed a particularly interesting class of new metallocenes that are suitable for use in the polymerization of olefins, namely bridged metallocenes having a terminally unsaturated group extending from the bridge. One particularly preferred metallocene of that type was the metallocene which can be called 1-(9-fluorenyl)-1-(cyclopentadienyl)-1-(methyl)-1-(but-3-enyl)methane zirconium dichloride. The metallocenes of that type were found to be particularly desirable in that they allowed for the production of solid catalyst systems that could be employed effectively in slurry polymerization processes.
The present invention is based on the subsequent discovery that metallocenes which have a bridge with a terminally unsaturated group and also an aryl substituent on the bridge produce unexpected benefits.
In accordance with the present invention there is provided a bridged metallocene in which two cyclodienyl-type groups are connected by a single carbon bridge which contains a terminally unsaturated substituent and an aryl substituent. In accordance with another aspect of the present invention there is provided olefin catalyst compositions comprising such metallocenes and a suitable cocatalyst. In accordance with yet another aspect of the present invention there is provided a process for polymerizing olefins using such catalyst systems.
The metallocenes of the present invention include those represented by the formula R(Z)(Z)MQk wherein each Z bound to M and is the same or different and is a cyclodienyl-type ligand selected from substituted or unsubstituted cyclopentadienyl, indenyl, tetrahydroindenyl, octahydrofluorenyl, and fluorenyl ligands; R is a structural bridge linking the Z""s which is a single carbon atom connecting the Z""s and which has its other valences satisfied by a terminally unsaturated hydrocarbyl substituent, preferably having 2 to 20 carbon atoms, and by an aryl group, preferably having 6 to 10 carbons atoms, and M is a metal selected from the group consisting of IVB, VB, and VIB metals of the periodic table, each Q is the same or different and is selected from the group consisting of hydrogen, halogens and organo radicals; k is a number sufficient to fill out the remaining valences of M.
A particularly preferred type of bridged metallocene includes those in which the olefinically unsaturated substituent has the formula
wherein Rxe2x80x3 is a hydrocarbyl diradical having 1 to 20 carbon atoms; more preferably 2 to 10; n is 1 or 0, and each Rxe2x80x2 is individually selected from the group consisting of organo radicals, most preferably alkyl radicals, having 1 to 10 carbon atoms and hydrogen. Most preferably Rxe2x80x3 has at least two carbons in its main alkylene chain, i.e. it is a divalent ethylene radical or a higher homolog thereof.
The present invention thus envisions bridged metallocenes prepared from vinyl terminated branched bridged ligands of the formula
wherein n is a number typically in the range of about 0 to 20; more preferably 2-10; wherein Rxe2x80x2 is selected from hydrogen, or organo groups having 1 to 10 carbons and Rxe2x80x2xe2x80x3 is an aryl radical having 6 to 20 carbon atoms. Currently preferred Rxe2x80x2 components are hydrogen or alkyl groups typically having 1 to 10 carbon atoms, or aryl groups typically having 6 to 10 carbon atoms. Z is a cyclodienyl-type radical as described earlier.
The metallocenes of such olefinically unsaturated branched-bridged ligands can be prepared by reacting the olefinically branched-bridged bis(cyclopentadienyl-type) ligand with an alkali metal alkyl to produce a divalent ligand salt that is then reacted with the transition metal compound to yield the metallocene, using the techniques generally known in the art for forming such metallocenes. See, for example, the technique disclosed in U.S. Pat. No. 5,436,305, the disclosure of which is incorporated herein by reference.
The necessary olefinically branched-bridged organic compounds suitable for use as ligands for such metallocenes can be made by reacting a suitable aryl, alkenyl ketone with an alkali metal salt of a cyclopentadiene-type compound such as cyclopentadiene or indene to form a 6-aryl, 6-terminal alkenyl fulvene then reacting the fulvene with an alkali metal salt of fluorene.
Some typical examples of some metallocenes containing a substituent having olefinic unsaturation include 1-(cyclopentadienyl)-1-(9-fluorenyl)-1-(but-3-enyl)-1-(phenyl)methane zirconium dichloride; 1-(cyclopentadienyl)-1-(9-fluorenyl)-1-(but-3-enyl)-1-(but-3-enyl)-1-(phenyl)methane zirconium dimethyl; 1-(3-methyl-cyclopentadienyl)-1-(9-fluorenyl)-1-(but-3-enyl)-1-(phenyl)methane zirconium dichloride; 1-(indenyl)-1-(9-fluorenyl)-1-(but-3-enyl)-1-(phenyl)methane zirconium dichloride; 1-(cyclopentadienyl)-1-(9-fluorenyl)-1-(pent-4-enyl)-1-(phenyl)methane zirconium dichloride; 1-(cyclopentadienyl)-1-(9-4,5-benzofluorenyl)-1-(but-3-enyl)-1-(phenyl)methane zirconium dichloride; and the like.
The inventive metallocenes are suitable for preparing catalysts for the polymerization of olefins. Such catalyst systems are prepared by combining at least one inventive metallocene with a suitable cocatalyst. It is also within the scope of the present invention to use two or more of the inventive metallocenes or an inventive metallocene in combination with one or more other metallocenes.
Examples of suitable cocatalysts include generally any of those organometallic compounds which have been found suitable as cocatalysts for metallocenes in the past. Some typical examples include organometallic compounds of the metals of Groups IA, IIA, and IIIB of the Periodic Table. Examples of compounds that have been used in the past as cocatalysts for metallocenes include organometallic halide compounds, organometallic hydrides, and even metal hydrides. Some specific examples include organoaluminum alkyl compounds such as triethylaluminum, triusobutyl aluminum, diethylaluminum chloride, ethyl aluminum dichloride, ethyl aluminum sesquichloride, diethylaluminum hydride, and the like. Other examples of known cocatalysts include compounds capable of forming stable non-coordinating counter anion such as those disclosed in U.S. Pat. No. 5,155,080. Examples of such is triphenyl carbenium tetrakis(pentafluorophenyl)boronate and tris(pentafluorophenyl)borane. Still another example of a cocatalyst would be a mixture of trimethylaluminum and dimethylfluoroaluminum such as disclosed in Zambelli et al, Macromolecules, 22, 2186 (1989).
There are three types of currently preferred catalyst systems. The first, referred to hereinafter as Catalyst System I, is prepared by prepolymerizing the metallocene in the presence of an alkylaluminoxane, optionally in the presence of a particulate material such as silica, and then washing out hydrocarbon soluble material to produce a solid particulate polymerization catalyst system. The second, referred to hereinafter as Catalyst System II is prepared by contacting a carrier with an alkyl aluminum compound and then contacting that product with water to produce a particulate cocatalyst which is then contacted with the metallocene to produce a particulate catalyst system, which may or may not be subjected to prepolymerization before use in forming polymer. The third, i.e. Catalyst System III, is prepared by contacting the metallocene with a relatively insoluble solid compound having aluminoxy groups. A currently preferred technique for making such a catalyst system involves contacting a solution of aluminoxane with a crosslinking agent, optionally in the presence of a particulate solid such as silica, to results in a solid cocatalyst having aluminoxy groups, then combining that solid with the metallocene to produce a solid catalyst system. The production of such solid cocatalysts is disclosed in U.S. Pat. Nos. 5,411,925; 5,354,721; and 5,436,212, the disclosures of which are incorporated herein by reference.
A particularly preferred embodiment involves the formation of Catalyst System I that is particularly useful for use in slurry form polymerization processes. Catalyst System I is prepared by combining the metallocene with an organoaluminoxane and conducting a prepolymerization to obtain a solid which is recovered and ultimately used as the catalyst system.
The organoaluminoxane component used in preparing the Catalyst System I is an oligomeric aluminum compound having repeating units of the formula
Some examples are often represented by the general formula (Rxe2x80x94Alxe2x80x94O"Parenclosest"n or R(Rxe2x80x94Alxe2x80x94Oxe2x80x94)nAlR2. In the general alumoxane formula R is a C1-C5 alkyl radical, for example, methyl, ethyl, propyl, butyl or pentyl and xe2x80x9cnxe2x80x9d is an integer from 1 to about 50 or greater. Most preferably, R is methyl and xe2x80x9cnxe2x80x9d is at least 4. Aluminoxanes can be prepared by various procedures known in the art. For example, an aluminum alkyl may be treated with water dissolved in an inert organic solvent, or it may be contacted with a hydrated salt, such as hydrated copper sulfate suspended in an inert organic solvent, to yield an aluminoxane. Generally the reaction of an aluminum alkyl with a limited amount of water is postulated to yield a mixture of the linear and cyclic species of the aluminoxane.
The first step of producing Catalyst System I involves combining the metallocene and aluminoxane in the presence of a suitable liquid to form a liquid catalyst system. It is preferred that the liquid catalyst system be prepared using an organic liquid in which the aluminoxane is at least partially soluble. The currently preferred liquids are hydrocarbons such as hexane or toluene. Typically some aromatic liquid solvent is employed. Examples include benzene, toluene, ethylbenzene, diethylbenzene, and the like. The amount of liquid to be employed is not particularly critical. Nevertheless, the amount should preferably be such as to dissolve the product of the reaction between the metallocene and the aluminoxane, provide desirable polymerization viscosity for the prepolymerization, and to permit good mixing. The temperature is preferably kept below that which would cause the metallocene to decompose. Typically the temperature would be in the range of xe2x88x9250xc2x0 C. to 100xc2x0 C. Preferably, the metallocene, the aluminoxane, and the liquid diluent are combined at room temperature, i.e. around 0 to 40xc2x0 C. The reaction between the aluminoxane and the metallocene is relatively rapid. The reaction rate can vary depending upon the ligands of the metallocene. It is generally desired that they be contacted for at least about a minute to about 1 hour.
It is within the scope of the invention to form the liquid catalyst system in the presence of a particulate solid. Any number of particulate solids can be employed as the particulate solid. Typically the support can be any organic or inorganic solid that does not interfere with the desired end result. Examples include porous supports such as talc, inorganic oxides, and resinous support materials such as particulate polyolefins. Examples of inorganic oxide materials include Groups II, III, IV or V metal oxides such as silica, alumina, silica-alumina, and mixtures thereof. Other examples of inorganic oxides are magnesia, titania, zirconia, and the like. Other suitable support materials which can be employed include materials such as, magnesium dichloride, and finely divided polyolefins, such as polyethylene. It is within the scope of the present invention to use a mixture of one or more of the particulate solids.
It is generally desirable for the solid to be thoroughly dehydrated prior to use, preferably it is dehydrated so as to contain less than 7% loss on ignition, more preferably less than 1%. Thermal dehydration treatment may be carried out in vacuum or while purging with a dry inert gas such as nitrogen at a temperature of about 20xc2x0 C. to about 1200xc2x0 C., and preferably, from about 300xc2x0 C. to about 800xc2x0 C. Pressure considerations are not critical. The duration of thermal treatment can be from about 1 to about 24 hours. However, shorter or longer times can be employed provided equilibrium is established with the surface hydroxyl groups.
Dehydration can also be accomplished by subjecting the solid to a chemical treatment in order to remove water and reduce the concentration of surface hydroxyl groups. Chemical treatment is generally capable of converting most or all of the water and hydroxyl groups in the oxide surface to relatively inert species. Useful chemical agents are for example, trimethylaluminum, ethyl magnesium chloride, chlorosilanes such as SiCl4, disilazane, trimethylchlorosilane, dimethylaminotrimethylslilane and the like.
The chemical dehydration can be accomplished by slurrying the inorganic particulate material such as, for example silica, in an inert low boiling hydrocarbon, such as for example, hexane. During the chemical dehydration treatment, the silica should be maintained in a moisture and oxygen free atmosphere. To the silica slurry is then added a low boiling inert hydrocarbon solution of the chemical dehydrating agent, such as, for example dichlorodimethylsilane. The solution is added slowly to the slurry. The temperature ranges during chemical dehydration reaction can be from about 20xc2x0 C. to about 120xc2x0 C., however, higher and lower temperatures can be employed. Preferably, the temperature will be about 50xc2x0 C. to about 100xc2x0 C. The chemical dehydration procedure should be allowed to proceed until all the substantially reactive groups are removed from the particulate support material as indicated by cessation of gas evolution. Normally, the chemical dehydration reaction will be allowed to proceed from about 30 minutes to about 16 hours, preferably, 1 to 5 hours. Upon completion of the chemical dehydration, the solid particulate material may be filtered under a nitrogen atmosphere and washed one or more times with a dry, oxygen free inert solvent. The wash solvents as well as the diluents employed to form the slurry and the solution of chemical dehydrating agent, can be any suitable inert hydrocarbon. Illustrative of such hydrocarbons are pentane, heptane, hexane, toluene, isopentane and the like.
Another chemical treatment that can be used on solid inorganic oxides such as silica involves reduction by contacting the solid with carbon monoxide at an elevated temperature sufficient to convert substantially all the water and hydroxyl groups to relatively inactive species.
The specific particle size of the support or inorganic oxide, surface area, pore volume, and number of hydroxyl groups is not considered critical to its utility in the practice of this invention. However, such characteristics often determine the amount of support to be employed in preparing the catalyst compositions, as well as affecting the particle morphology of polymers formed. The characteristics of the carrier or support must therefore be taken into consideration in choosing the same for use in the particular invention. It is also within the scope of the invention to use two or more of the dehydration techniques in combination, such as thermal dehydration followed by treatment with trimethylaluminum.
It is also within the scope of the present invention to add such a particulate solid to the liquid catalyst system after it has been formed and to carry out the prepolymerization in the presence of that solid.
The amount of aluminoxane and metallocene used in forming the liquid catalyst system for the prepolymerization can vary over a wide range. Typically, however, the molar ratio of aluminum in the aluminoxane to transition metal of the metallocene is in the range of about 1:1 to about 20,000:1, more preferably, a molar ratio of about 50:1 to about 2000:1 is used. If a particulate solid, i.e. silica, is used generally it is used in an amount such that the weight ratio of the metallocene to the particulate solid is in the range of about 0.00001/1 to 1/1, more preferably 0.0005/1 to 0.2/1.
The prepolymerization is conducted in the liquid catalyst system, which can be a solution, a slurry, or a gel in a liquid. A wide range of olefins can be used for the prepolymerization. Typically, the prepolymerization will be conducted using an olefin, preferably selected from ethylene and non-aromatic alpha-olefins, and as propylene. It is within the scope of the invention to use a mixture of olefins, for example, ethylene and a higher alpha olefin can be used for the prepolymerization. The use of, a higher alpha olefin, such as 1-butene, with ethylene is believed to increase the amount of copolymerization occurring between the olefin monomer and the olefinically unsaturated portion of the metallocene.
The prepolymerization can be conducted under relatively mild conditions. Typically, this would involve using low pressures of the olefin and relatively low temperatures designed to prevent site decomposition resulting from high concentrations of localized heat. The prepolymerization typically occurs at temperatures in the range of about xe2x88x9215xc2x0 C. to about +110xc2x0 C., more preferably in the range of about 0 to about +30xc2x0 C. The amount of prepolymer can be varied but typically would be in the range of from about 1 to about 95 wt % of the resulting prepolymerized solid catalyst system, more preferably about 5 to 80 wt %. It is generally desirable to carry out the prepolymerization to at least a point where substantially all of the metallocene is in the solid rather than in the liquid since that maximizes the use of the metallocene.
After the prepolymerization, the resulting solid prepolymerized catalyst is separated from the liquid of the reaction mixture. Various techniques known in the art can be used for carrying out this step. For example, the material could be separated by filtration, decantation, or by vacuum evaporation. It is currently preferred, however, not to rely upon vacuum evaporation since it is considered desirable to remove substantially all of the soluble components in the liquid reaction product of the prepolymerization from the resulting solid prepolymerized catalyst before it is stored or used for subsequent polymerization. After separating the solid from the liquid, the resulting solid is preferably washed with a hydrocarbon and then dried using high vacuum to remove substantially all the liquids and other volatile components that might still be associated with the solid. The vacuum drying is preferably carried out under relatively mild conditions, i.e. temperatures below 100xc2x0 C. More typically the prepolymerized solid is dried by subjection to a high vacuum at a temperature of about 30xc2x0 C. until a substantially constant weight is achieved. A preferred technique employs at least one initial wash with an aromatic hydrocarbon, such as toluene, followed by a wash with a paraffinic hydrocarbon, such as hexane, and then vacuum drying.
It is within the scope of the present invention to contact the prepolymerization reaction mixture product with a liquid in which the prepolymer is sparingly soluble, i.e. a countersolvent for the prepolymer, to help cause soluble prepolymer to precipitate from the solution. Such a liquid is also useful for the subsequent washing of the prepolymerized solid.
It is also within the scope of the present invention to add a particulate solid of the type aforementioned after the prepolymerization. Thus one can add the solid to the liquid prepolymerization product before the countersolvent is added. In this manner soluble prepolymer tends to precipitate onto the surface of the solid to aid in the recovery of the filtrate in a particulate form and to prevent agglomeration during drying. The liquid mixture resulting from the prepolymerization or the inventive solid prepolymerized catalyst can be subjected to sonification to help break up particles if desired.
Further, if desired the recovered solid prepolymerized catalyst system can be screened to give particles having sizes that meet the particular needs for a particular type of polymerization.
Another option is to combine the recovered inventive solid prepolymerized catalyst system with an inert hydrocarbon, such as one of the type used as a wash liquid, and then to remove that liquid using a vacuum. In such a process it is sometimes desirable to subject the resulting mixture to sonification before stripping off the liquid.
The resulting solid prepolymerized metallocene-containing catalyst system is useful for the polymerization of olefins. Generally, it is not necessary to add any additional aluminoxane to this catalyst system. In some cases it may be found desirable to employ small amounts of an organoaluminum compound as a scavenger for poisons. The term organoaluminum compounds include compounds such as triethylaluminum, trimethylaluminum, diethylaluminum chloride, ethylaluminum dichloride, ethylaluminum sesquichloride, and the like. Trialkylaluminum compounds are currently preferred. Also in some applications it may be desirable to employ small amounts of antistatic agents which assist in preventing the agglomeration of polymer particles during polymerization. Still further, when the inventive catalyst system is added to a reactor as a slurry in a liquid, it is sometimes desirable to add a particulate dried solid as a flow aid for the slurry. Preferably the solid has been dried using one of the methods described earlier. Inorganic oxides such as silica are particularly preferred. Currently, it is preferred to use a fumed silica such as that sold under the tradename Cab-o-sil. Generally the fumed silica is dried using heat and trimethylaluminum.
Catalyst System II is prepared by reacting an organoaluminum compound with a suitable carrier and then with water to produce a solid which can be used as a cocatalyst for transition metal olefin polymerization catalysts.
The terms xe2x80x9ccarrierxe2x80x9d as used herein refer to the material that results in a solid product when reacted with the organoaluminum compound and water. The carrier thus does not have to actually be a solid. It is contemplated that the carrier can be any organic, organometallic, or inorganic compound capable of affixing the organoaluminum compound either through absorption, adsorption, Lewis Acid/Lewis Base interactions, or by reaction with hydroxyl groups of the carrier.
A wide range of materials can be used as the carrier. Generally, any material that will result in a solid cocatalyst that remains insoluble in the polymerization diluent during the polymerization process can be employed as the carrier. Thus the carrier includes materials that form solids when reacted with an organoaluminum compound and water as well as solids that are insoluble in the particular liquid diluent that is present during the polymerization. It is generally preferred that the carrier be capable of yielding a particulate solid cocatalyst. The carrier can be a material having surface groups which are known to react with organoaluminum compounds or a material which is free of surface groups which react with organoaluminum compounds. Some examples of materials envisioned for use as a carrier include starch, lignin, cellulose, sugar, silica, alumina, silica-alumina, titania, zirconia, zeolites of silica and/or alumina, magnesia, calcium carbonate, aluminum trifluoride, boron oxide, magnesium dichloride, boric acid, activated carbon, carbon black, organoboranes, organoboroxines, Si(OMe)3Me, hydrocarbyl polyalcohols, boric acid, alumina, polyethylene, polyethylene glycol, and the like. One embodiment comprises dissolving polyethylene in a suitable organic solvent then adding the organoaluminum compound and then adding the water to produce a solid cocatalyst. It is generally preferred that the carrier that is reacted with the organoaluminum compound be relatively free of water, i.e. that it contain less than about 5 weight percent Water, more preferably less than 1 weight percent water.
The term organoaluminum compound as used herein with reference to forming Catalyst System II, refers to compounds of the formula Rn AlX3xe2x88x92n wherein n is a number in the range of 1 to 3, each R is the same or different organo radical, preferably a hydrocarbyl radical, and each X is a halide. Typically the organo radicals would have 1 to 12 carbon atoms, more preferably 1 to 5 carbon atoms. Some examples of organoaluminum compounds include trialkylaluminum compounds, triarylaluminum compounds, dialkylaluminum hydrides, diarylaluminum hydrides, aryl alkyl aluminum hydrides, dialkylaluminum halides, alkyl aluminum dihalides, alkyl aluminum sesquihalides, and the like. Some specific examples of such organoaluminum compounds include trimethylaluminum, triethylaluminum, dimethylaluminum chloride, triisopropylaluminum, triisobutylaluminum, trihexylaluminum, diethylaluminum chloride, ethyl aluminum dichloride, ethyl aluminum sesquichloride, dimethyl aluminum chloride, and the like. The currently preferred organoaluminum compounds are the alkyl aluminum compounds, especially the trialkylaluminum compounds, with trimethylaluminum being particularly preferred. It is also within the scope of the present invention to use mixtures of such organoaluminum compounds.
The organoaluminum compound can be contacted with the carrier in a suitable manner. For example a particulate solid carrier could be contacted with a suitable gas containing the organoaluminum compound and then contacted with a gas containing water liquid diluent. Alternatively, the carrier and the organoaluminum compound can be contacted in an organic liquid and then the resulting product contacted with water. Preferably the organic liquid diluent is anhydrous, i.e. substantially free of water. Examples of what is meant by organic liquid include hydrocarbons such as heptane, octane, decane, dodecane, kerosene, cyclopentane, cyclohexane, methylcyclopentane, benzene, toluene, and xylene as well as halogenated compounds such as chlorobenzene and the like, as well as mixtures thereof. It is within the scope of the invention to simply admix the carrier and a liquid diluent solution of the organoaluminum compound. Another option is to add a solution of the organoaluminum compound to a slurry of the carrier in a liquid diluent.
The amount of liquid diluent employed can vary over a wide range. Typically the amount of liquid, including liquid accompanying the added organoaluminum compound, would be in the range of about 0.1 to about 5000 ml/gram of carrier or more often about 5 to about 200 ml/gram of carrier. The amount of the organoaluminum compound relative td the carrier can vary over a wide range depending upon the particular material selected as the carrier and the particular results desired. The amount necessary to provide the greatest yield of the most active cocatalyst for a specific carrier and a specific organoaluminum compound can be readily determined by routine experimentation. A typical range for the amount of the organoaluminum compound would be from about 0.0001 moles/gram of carrier to about 1 mole/gram of carrier.
The temperature at which the organoaluminum compound and the carrier are contacted can vary over a wide range. Typically it would be carried out at a temperature in the range of about xe2x88x9250xc2x0 C. to about the boiling point of the liquid diluent, if used, more generally in the range of about xe2x88x9250xc2x0 C. to about 200xc2x0 C. It is currently preferred to carry out the contacting at a temperature in the range of about 10 to about 100xc2x0 C. Higher temperatures can speed up the process for producing the solid cocatalyst. Higher pressures can allow for the use of higher temperatures.
After the contacting of the carrier with the organoaluminum compound is complete the resulting product is contacted with water. This is the most critical step of producing the solid cocatalyst. The water can be introduced in any convenient manner. For example, a slurry of water in a hydrocarbon can be added to liquid containing the reaction product or water can just be added directly to the liquid containing the reaction product. Other options would include adding ice or adding a solid containing water. Preferably, for safety reasons the water is added slowly while the slurry is agitated as by stirring. It is currently preferred to introduce the water into the slurry as a gas, preferably in an inert carrier gas such as nitrogen or argon. The introduction of the water via an inert carrier gas has been found to result in a more uniform distribution of the cocatalyst components on the surface of the carrier. The temperature employed during the water addition can vary over a wide range depending upon the technique being employed but is typically in the range of about xe2x88x92100xc2x0 C. to about 100xc2x0 C. In a preferred embodiment, in which the water is added to the water via an inert gas, the gas is passed through a heated vessel containing water and is then passed into the vessel containing the slurry, which is also preferably heated.
The amount of water necessary to produce the cocatalyst for Catalyst System II can vary depending upon the particular carrier selected, the amount of organoaluminum compound employed, and the amount of groups on that carrier which will react with the organoaluminum comipound. The optimum amount of water to be added for a particular carrier can be readily determined by routine experimentation. Generally the water will be employed in an amount such that the molar ratio of added water to the aluminum of the organoaluminum compound will be in the range of about 0.1/1 to about 3/1, more preferably the range for the molar ratio of the water to the aluminum of the organoaluminum compound is in the range of about 0.2/1 to about 1.5/1, or even still more preferably about 0.5/1 to about 1.2/1. The reaction time can range from a few minutes to several hours and can often be monitored by observing the temperature and/or the evolution of gases.
After the reaction with the water has been completed, the resulting solid product is combined with a metallocene to form Catalyst System II. In one preferred embodiment, the Catalyst System is subjected to a prepolymerization, preferably in the presence of hydrogen, before being actually used to produce commercial scale quantities of polymer. The prepolymerization can be conducted using the same type of monomers and conditions as described above in regard to Catalyst System I.
The metallocene can be combined with the cocatalyst in any suitable manner. One technique involves adding the metallocene to a slurry resulting from the production of the cocatalyst, or alternatively, the solids of the slurry can be filtered and optionally washed and then cormbined with the metallocene catalyst, or the liquid of the slurry can be evaporated and the resulting solids then combined with the metallocene catalyst to form the solid catalyst system. Typically, the metallocene catalyst is combined with the solid cocatalyst in a liquid diluent, preferably a liquid diluent in which the catalyst is soluble. The resulting catalyst system can be prepolymerized directly or it can be separated from the liquid and then prepolymerized. Such a recovered solid catalyst system can be washed with a hydrocarbon, preferably an aliphatic hydrocarbon, and dried, preferably under a high vacuum before being prepolymerized.
The amount of the metallocene that is combined with the inventive cocatalyst can vary over a wide range depending upon the particular catalyst and cocatalyst selected and the particular results desired. Typically the polymerization catalyst is employed in such an amount that the atomic ratio of the Al of the cocatalyst to the metal of the polymerization catalyst is in the range of about 1/1 to about 10000/1, more preferably about 10/1 to 1000/1.
The temperature at which the metallocene and the cocatalyst are combined is not considered to be particularly critical. Typically this is done at temperatures in the range of about xe2x88x9250xc2x0 C. to about 300xc2x0 C., or more preferably about 0xc2x0 C. to about 100xc2x0 C., or still more preferably about 10xc2x0 C. to about 80xc2x0 C . Typically the catalyst system can be employed shortly after the inventive cocatalyst and the polymerization catalyst are brought together.
The prepolymerization can be conducted using olefins such as those normally polymerized by the polymerization catalysts. The currently preferred olefin being ethylene either alone or in combination with alpha olefins such as propylene, butene, 1-hexene, 4-methyl-1-pentene, and the like. The prepolymerizations can be conducted under a wide range of conditions. Typically it is preferred to conduct the prepolymerization in a liquid diluent at temperatures in the range of about xe2x88x9215xc2x0 C. to about 200xc2x0 C., more typically about 0xc2x0 C. to about 100xc2x0 C. The amount of prepolymerization conducted can vary; however, typically would be such that the prepolymer would be in the range of from about 1 to about 95 weight percent of the resulting prepolymerized catalyst system, more preferably about 5 to 80 weight percent.
In a currently preferred embodiment, a prepolymerized catalyst system is prepared by reacting the carrier with the organometallic compound in a liquid diluent, then adding the water to that slurry, then after the reaction is substantially complete adding the metallocene to the slurry, then the slurry is contacted with an olefin under prepolymerization conditions in the presence of hydrogen to produce a prepolymerized solid catalyst system which can be used as is in the slurry or separated from the liquid and dried for subsequent use in a polymerization. While the dried catalyst system can be subjected to washing with a hydrocarbon before being used in a subsequent polymerization, it has been noted that more active catalyst systems in terms of grams of polymer per gram of transition metal result if there is no such washing step.
The catalyst systems of the present inventionare particularly useful for the polymerization of alpha-olefins having 2 to 10 carbon atoms. Examples of such olefins include ethylene, propylene, butene-1, pentene-1, 3-methylbutene-1, hexene-1, 4-methylpentene-1, 3-methylpentene-1, heptene-1, octene-1, decene-1, 4,4-dimethyl-1-pentene, 4,4-diethyl-1-hexene, 3,4-dimethyl-1-hexene, and the like and mixtures thereof. The catalysts are also useful for preparing copolymers of ethylene and propylene and copolymers of ethylene or propylene and a higher molecular weight olefin. The catalysts can also be used to produce ethylene-propylene-diene (EPDM) polymers and ethylene-propylene rubber (EPR).
The polymerizations can be carried out under a wide range of conditions depending upon the particular metallocene employed and the particular results desired. Catalyst systems within the scope of this invention are considered to be useful for polymerization conducted under solution, slurry, or gas phase reaction conditions.
When the polymerizations are carried out in the presence of liquid diluents obviously it is important to use diluents which do not have an adverse effect upon the catalyst system. Typical liquid diluents include propane, butane, isobutane, pentane, hexane, heptane, octane, cyclohexane, methylcyclohexane, toluene, xylene, and the like. Typically the polymerization temperature can vary over a wide range, temperatures typically would be in a range of about xe2x88x9260xc2x0 C. to about 300xc2x0 C., more preferably in the range of about 20xc2x0 C. to about 160xc2x0 C. Typically the pressure of the polymerization would be in the range of from about 1 to about 500 atmospheres or even greater. The inventive catalyst system is particularly useful for polymerizations carried out under particle form, i.e., slurry-type polymerization conditions.
It is contemplated that the catalyst systems of the present invention can be employed in generally any type of polymerization where similar catalysts have been employed in the past. The solid inventive catalyst systems are considered to be particularly well suited for slurry type polymerization processes. The conditions employed when using the catalyst systems of the present invention can be the same as those used with prior art systems. Typically when the polymerization is carried out in the presence of a liquid the polymerization will be conducted at a temperature in the range of about xe2x88x9250xc2x0 C. to about 300xc2x0 C. and the pressure will be from about normal atmospheric pressure to about 2000 kg/cm2. In some cases it may be desirable to add some additional organoaluminum compound to the polymerization vessel, such as triethylaluminum or triisobutylaluminum as a poison scavenger.
A further understanding of the present invention, its objects, and advantages will be provided by the following examples. | {
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An annuity is a type of insurance service. In general terms, in an annuity contract, an insurance company and an annuitant contract for the annuitant to make one or more payments to the insurance company. For that consideration, the insurance company makes periodic payments to an annuitant. By way of example, the insurance company may be obliged to make a payment of a predetermined amount to the annuitant annually for a predetermined time period. In another example, the insurance company is obliged to make payments of a predetermined amount to the annuitant annually for the life of the annuitant.
In a typical annuity product, an asset value associated with an account is annuitized. In other words, the asset value is not available for use by the annuitant, or for use in estate planning.
In the prior art, one exemplary product provides a variable annuity, based on a single premium, which also includes a stream of payments, funded by an additional fee, that commences at an age selected by the annuitant. | {
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Many computers are now interconnected in one or more networks or internetworks. One of the most widely used communications networks is the worldwide packet data communications network known as the Internet. The Internet provides access to enormous amounts of information and may be used to transport electronic mail (“email”). A user of a network such as the Internet is associated with a unique email address. The email address may represent an account that is maintained on an email server. Anyone with a computer and an email processing program (“email client”) can remotely send one or more email messages to any address among millions of addresses, and the recipient may use its email client to read the messages.
Despite the benefits provided by the Internet, users have recently recognized important security issues associated with Internet email. First, the complexity of the Internet allows information to fall into the hands of unintended third parties. For example, when an email is sent via the Internet, the email may travel through numerous sub-networks to reach its destination. Many of these sub-networks include locations where data is temporarily stored before being forwarded to the next location. As a result, copies of an email may be stored at numerous locations unknown to the sender, even though the sender only intended for the email to be provided to a particular recipient or group of recipients. Further, email is easily forwarded to other recipients that are not known to the original sender. As a result, although a sender intends for only a particular recipient to receive a particular email, the email may be forwarded to and received by other recipients.
Once the email has been transported via the Internet, deleting all copies of the email can be difficult, if not impossible, to accomplish. Consider a sensitive email that has been sent via the Internet and now needs to be completely deleted. Locating and deleting the email from the sending and receiving locations is relatively straightforward. However, locating and deleting all copies of the email is difficult, if not impossible, because of the difficulty in determining the locations of all copies of the email. Because the Internet is a packet-switched network, data packets that make up a particular message, or a complete copy of a message, may be stored on intermediate servers of internetworks logically located between sender and recipient; the location of such servers is not predictable. Furthermore, even if all copies of the email are located, special privileges or permissions may be required to delete the copies. For example, some copies may reside on servers in remote locations in other countries. As a result, deleting all copies of the email may be extremely difficult, if not impossible, to accomplish.
These problems are not limited to the Internet. Many corporations have extensive communication networks that have numerous servers, archives, hubs and backup systems where email might be stored. Moreover, these problems are not limited to email, but apply to any type of information transported over communication networks.
Based on the foregoing, there is a need to control access to information disseminated on communications networks. There is a particular need for a comprehensive approach for controlling and tracking access to data disseminated on communications networks. | {
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The present invention relates generally to cellular communication devices and, more particularly, to a cellular alert device for notifying a user that a cellular call is being received by an associated cellular telephone with the alert device not being in close proximity or in data communication with the associated telephone.
Cellular phones, including digital walkie-talkie type telephones, are in popular use by consumers, both for personal and business communications. A common problem, however, is that cell phone users do not always have their cell phones in close proximity to their person when a call is received and, thus, are not available to answer it. For example, men in the workplace may keep their portable telephones in a desk drawer and miss calls when they are not near their desks when a call comes in. Similarly, women sometimes leave their cell phones in their purses which may then be situated away from them when a call is received. Still another frequently experienced example is when a cell phone owner is engaged in a leisure activity, such as swimming, boating, or working out in a gym, and have stowed their phone in a locker, vehicle, or the like.
Various proposals for alerting a user that an incoming call is being received by the user's cell phone have been made in the art. More particularly, U.S. Pat. No. 6,218,958 to Eichstaedt discloses a tactile notification device that can be worn by a person and which can receive alert signals from a plurality of other personal computing devices, such as a cell phone, pager, or laptop computer (also being worn by the user) and generates respective tactile signals detectable by the user. Although assumably effective for its intended purpose, this system requires multiple other devices to transmit a signal to the alert device receiver and requires the other devices to be in close proximity to the alert device.
While still other patents have proposed having an alert device for notifying a user that a cell phone or other personal electronic device has been actuated, there is a need for a device that may be actuated independent of the cell phone itself and that does not require transmission of an auxiliary signal by the cell phone.
Therefore, it would be desirable to have a cell phone alert device for notifying a cell phone owner that an associated cell phone is presently receiving an incoming transmission. Further, it would be desirable to have a cell phone alert device that receives said incoming call notification independently of the telephone itself, even if separated from the telephone by a relatively long distance. In addition, it would be desirable to have a cell phone alert device that receives the incoming call notification substantially simultaneously with the associated telephone's receipt thereof. And, it would also be desirable if the cell phone alert device could be worn by a user in a convenient and fashionable manner | {
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This invention relates to a fuel/air mixing arrangement of the radial inflow type for combustion apparatus such as burners in gas turbine engines. It has a particular applicability to gas-fueled gas turbines.
Both efficiency and environmental considerations mean that it has become essential to ensure that the levels of pollutant emission from combustion apparatus are kept as low as possible and various measures have been proposed with that aim in mind. For example, in the field of gas turbine engines, `lean-burn` combustion systems are well-known. In such systems, the air/fuel ratio is at or near stochiometric and, specifically when the engine is running at or near full load, harmful exhaust pollutants, specifically CO, NO.sub.x and unburnt hydrocarbons are produced in relatively small amounts. However, at lower loads, known lean-burn configurations may not be so advantageous and, inter alia, difficulty may be experienced in maintaining flame stability to the extent that flame-out may occur due to the weak fuel content and the low velocity of the mixture.
Past proposals for overcoming such problems have generally utilized complicated arrangements for adjusting the operation of the engine to improve low-load performance. Inter alia, there have been proposed fuel staging arrangements whereby fuel is injected in stages depending on the load under which the engine is operating, with additional stages being brought into operation as the engine load increases. In other arrangements, a pilot flame is maintained by injecting fuel directly and axially into the center of a swirler to give a fuel-rich central zone with improved flame stability. However, pilot flame systems usually give higher levels of pollution when operating at low load. All these various arrangements can involve fairly complicated control systems for ensuring the right amount of fuel is being injected at the right time and to the right place. | {
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Heparin is an acid mucopolysaccharide found in the liver, intestines, lungs, skin, and the like, and contains sulfated D-glucosamine, D-glucuronic acid, L-iduronic acid, and the like.
Heparin has a strong anticoagulant activity, and is hence used to treat disseminated intravascular coagulation syndrome (DIC), treat and prevent various thromboembolisms (venous thrombosis, myocardial infarction, pulmonary embolism, cerebral embolism, thromboembolism in upper and lower extremities, pre/post operation thromboembolism, or the like), prevent the blood coagulation at the occasions of extracorporeal circulation apparatus use for haemodialysis, artificial heart and lung, or the like, vessel catheter insertion, blood transfusion, blood tests, or the like.
Further, heparin is known to have many physiological activities, in addition to the anticoagulant activity, such as lipoprotein lipase activation action, antiplatelet aggregation action, hypotensive action, anticomplementary action, cancer metastasis inhibitory action, inhibitory effect on degranulation from mast cells, local inflammation suppression, analgesic action and blood circulation improving action on muscle tissues, and the like.
Heparin is produced by the extraction/fractionation from tissues of principally healthy edible animals, but, ever since the BSE (bovine spongiform encephalopathy) incidence, heparin used as pharmaceutical products is mostly originated from porcine intestinal mucosa. Typically, the porcine intestinal mucosa is suspended in an aqueous solvent for proteolytic digestion, and subsequently an adsorbent, or the like, (Non Patent Literature 1), is added thereto to extract heparin and other mucopolysaccharides (principally chondroitin sulfate family, heparan sulfate, and the like) as a complex to use as a crude material. Then, the crude material is batch mixed/fractionated to obtain heparin (so-called “unfractionated heparin”).
The heparin (unfractionated heparin) obtained by the above method contains mucopolysaccharides (mainly heparan sulfate, chondroitin sulfates B and C) other than the heparin, and it is known that the content thereof varies depending on the crude material and production method. However, the side effects caused by those impurities are roughly confirmed and accepted, and as a result, the unfractionated heparin has been used as a pharmaceutical product for many years.
However, in the early 2008, there were many cases reported in the U.S. and Germany that patients administered with an unfractionated heparin preparation by bolus injection (rapid intravenous injection) experienced unusual side effects, and the incidence eventually caused more than 80 deaths. The US FDA analyzed the unfractionated heparin preparation and the bulk drug thereof and confirmed that they were evidently different from the conventional products, and further revealed that oversulfated chondroitin sulfate (OSCS) was identified to have been present in them (Non Patent Literatures 2 to 4). This does not exist as such in nature, and is believed to have been most likely mixed in at the time of bulk drug production.
Serious side effects were not reported in Japan, but a part of the unfractionated heparin preparations and low molecular weight heparin (LMWH) preparations were recalled which caused serious problems in the stable supply to the market.
Many researchers have been studying on OSCS for scientific synthesis methods, the structure analysis, investigation to determine the causes of adverse events by animal tests, or the like, particularly studying on the purity and safety assessment by 1H-NMR, other test methods, or the like, (Non Patent Literatures 5 and 6), and OSCS has been specified as the causative substance of adverse events in Japan and thus safety/purity tests have been reviewed by administration agencies and preparation manufacturers (Non Patent Literatures 7 and 8).
Meanwhile, the methods described in 1) Non Patent Literature 1, 2) Non Patent Literature 9, 3) Non Patent Literature 10, 4) Patent Literature 1, and the like, are known for producing or purifying heparin.
However, there has been no method known for easily and effectively removing impurities such as OSCS, chondroitin sulfate, and the like, from heparin. Further, there has been no method known for easily detecting or measuring such impurities in heparin. | {
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Japanese Unexamined Patent Application Publication No. 2001-296430 discloses a fiber cleaver including a body having a holder guide to which an optical fiber holder is attached, a lid openably and closably provided on the upper surface of the body, a slider movable along a linear guide fixed to the body, and a circular blade fixed to the slider and making an initial flaw in an optical fiber.
In this fiber cleaver, if the circular blade is repeatedly used many times, the sharpness of the circular blade deteriorates. Therefore, it is proposed that the circular blade be rotatably attached to the slider and, when the sharpness of the circular blade has deteriorated, the circular blade is rotated by a certain angle such that the point of contact of the circular blade with respect to the optical fiber is changed. However, in such a case where the circular blade is rotated by the worker after members that fix the circular blade are loosened by the worker, the workload imposed on the worker increases and, moreover, it is difficult to appropriately change the point of contact of the circular blade with respect to the optical fiber. Hence, it is difficult to efficiently use the circular blade. | {
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The present invention generally relates to parking brakes and more particularly relates to an electric parking brake system for a vehicle with an electronic control device controlling a wheel brake device and an operating element for actuating the electric parking brake system.
An electric parking brake system of the general type shown herein has already been disclosed in DE 41 29 919 A1. This publication describes a parking brake in the form of a power-brake system, in which the brake is actuated by an electric motor, with an electronic controller being electrically connected to sensors detecting the operating state of the vehicle. The electronic controller controls the brake-applying and releasing operations of the wheel brakes subject to signals coming from a brake-applying device and/or the sensors.
It has to be mentioned, that the provisions of ECE R 13.09 5.2.1.26.2 which apply to permits as of Feb. 22, 1997, require that electric parking brake systems (EPB) with an electric transmission device must be operable from the driver""s seat in case of an electric error, thus achieving a predefined locking effect. This locking effect relates to the static test on an inclined plane with a gradient of 18%. In the vehicle classes M1 and N1 resulting from the above-mentioned provisions, the effect of the transmission brake may also be used. Furthermore the EPB complying with the provisions mentioned above has to be released by devices carried in the vehicle.
It is the object of the present invention to avoid the disadvantages of the prior art and to create an electric parking brake system with expanded functionality, higher safety and improved comfort. In particular, the present invention shall provide a parking brake system enabling a controlled power braking, especially during travel, with high dynamics and involving slip-control processes.
The object according to the present invention is achieved in that an actuation of the operating element alternatively applies and releases the electric parking brake according to the driver""s request, if the vehicle is in a resting position.
According to one preferred embodiment of this invention, the actuation of the operating element applies the electric parking brake as long as said element is actuated, if the vehicle is travelling. Thus, a controlled braking can be executed in consideration of the current driving situation.
For reasons of safety, it is desirable that the electric parking brake according to the invention is provided with at least one sensor detecting the blocking of a wheel and consequently feeding a signal to the electric control unit. In order to avoid an uncontrolled driving condition, the electric control unit releases a brake application on the wheel as a reaction to the signal of at least one sensor.
An improvement of the present invention includes a parking operative mode of the parking brake system according to the present invention, in which, for reasons of comfort, the control unit automatically locks the electric parking brake system if the vehicle is parked.
A comfortable and safe further development of the present invention includes a first starting operative mode of the electric parking brake system according to the present invention, in which the electric control unit automatically releases the electric parking brake when starting the parked vehicle.
According to another development of the present invention, a second starting operative mode of the electric parking brake system according to the present invention is foreseen in which the electric control unit applies the parking brake system before starting the vehicle, if an operating element is actuated, releasing the brake during the starting process by means of suitable dynamics.
Advantageously, a third starting operative mode is foreseen, in which the electric control unit applies the electric parking brake system independently before starting the vehicle releasing it during the starting process. Thus it is avoided that the vehicle rolls away against the starting direction, wherein the desired starting direction can be determined e.g. by the selection of the speed (Hillholder).
Preferably, the electric parking brake includes at least one sensor detecting the angle of inclination of the vehicle and thus delivering a signal to the electronic control unit. In such a way the parking brake system can cause or support a braking process on the basis of an inclination without the driver having to initiate a separate braking process.
Just when parking in the vehicle, the driver has to execute a lot of activities. Therefore one way of parking in, in which the electronic control unit automatically actuates the electric parking brake system during the parking-in process, results in a particularly safe and comfortable operation of the parking brake system according to the present invention.
Advantageously, the parking brake system according to the present invention includes at least one distance sensor determining the distance between the vehicle and an obstacle, especially another vehicle, and delivering a signal to the electric control unit as a reaction to this. In such a way, the parking brake system according to the present invention can avoid a collision with the obstacle, especially when the vehicle is parked in. | {
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Memory provides data storage for electronic systems. Flash memory is one type of memory, and has numerous uses in modern computers and devices. For instance, modern personal computers may have BIOS stored on a flash memory chip. As another example, it is becoming increasingly common for computers and other devices to utilize flash memory in solid state drives to replace conventional hard drives. As yet another example, flash memory is popular in wireless electronic devices because it enables manufacturers to support new communication protocols as they become standardized, and to provide the ability to remotely upgrade the devices for enhanced features.
NAND may be a basic architecture of integrated flash memory. A NAND cell unit comprises at least one selecting device coupled in series to a serial combination of memory cells (with the serial combination commonly being referred to as a NAND string). NAND architecture may be configured to comprise vertically-stacked memory cells. It is desired to develop improved NAND architecture, and improved methods of forming NAND architecture. | {
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1. Field of the Invention
The present invention relates generally to structural support systems in which high thermal gradients combine with high mechanical loads to potentially produce unacceptably high stress levels. In particular, the invention deals with the aft mounting system for transition duct members of cannular gas turbine combustion systems of advanced design. More specifically, the invention deals with the means of firmly attaching the transition duct member walls to structural members of the gas turbine without causing thermal or mechanical stresses in excess of those allowed by the materials.
2. Description of the Prior Art
In recent years advanced design gas turbine machines have been introduced to operate at increased turbine cycle temperatures to meet ever increasing load and efficiency requirements. These higher temperatures have combined with increased mechanical and aerodynamic loading to significantly increase the problems in obtaining long reliable life for those components directly subjected to the hot gas temperatures. In particular, in heavy duty gas turbines with cannular type combustion systems the transition duct members hereafter referred to as transition ducts or ducts, operate with wall temperatures approaching 1500.degree. F. while the surrounding machine structure and compressor discharge air is only at about 650.degree. F. This temperature difference tends to produce high thermal stresses particularly at the duct wall-to-support structure interfaces. Additional environmental factors such as combustion instability, machine vibration, buffeting due to external air flow, and the relatively high weight of the transition ducts impose large mechanical loads and resultant stresses in the aforementioned interface region between the duct wall and support structures.
The principal support for transition ducts in heavy-duty gas turbine combustion systems of the cannular type is at the aft (downstream) end of the ducts, just ahead of the first stage turbine nozzle. Axial, radial, circumferential, and torsional support are all required at the aft end. Conventionally, the required support has been provided by a series of flat plate gussets welded approximately perpendicular to the transition duct member outer wall, and then welded to a base plate which is in turn bolted to the first stage nozzle retaining ring structure. As turbine inlet temperatures have risen, it has been suggested to provide means to cool the transition duct wall-to-gusset joint to extend the capabilities of this simple, relatively inexpensive, support system. Such cooling has limited mitigating effects on the basic shortcomings of this support system.
Known support systems experience significant shortcomings due to concentrations of both mechanical and thermal stresses at the welded joint between the gusset(s) and the transition duct wall, particularly at the ends of this joint. The stresses result from the basic geometry of the interface. In addition, these high stresses occur where the material properties have been degraded by the weld process itself.
A further disadvantage of prior art systems is in the forward end to aft end radial support redundancy. Because of thermal growth differences and manufacturing tolerance stack-up between the forward and aft ends of the transition duct, there are additional built-in assembly and operational stresses to the forward and aft end support systems which further contribute to the low operational lifetimes for the effected parts.
A typical prior art gusset mount at the aft end of a gas turbine transition duct member is shown in U.S. Pat. No. 3,750,398 to Adelizzi. Therein, simple brackets (one for each transition duct) are secured by welding to the aft end of the transition duct, and are affixed by bolting to the machine inner casing. A somewhat similar weld/bolt transition duct member support is disclosed in U.S. Pat. No. 3,609,968 to Mierley, Sr., et al.
Prior patents showing the use of pivoting mounting devices to support aft portions of transition duct members include U.S. Pat. Nos. 3,481,146 to Jackson et al; 2,547,619 to Buckland; 2,529,958 to Owner et al; and 2,511,432 to Feilden. These patents are directed to providing retaining means which permit compensation for thermally induced displacements along various axes and generally recognize the need for avoiding excessive rigidity in combustion support systems. | {
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1. Field of the Invention
This invention relates generally to a two component effervescent dentifrice wherein, upon mixing of the separate components during brushing, significantly enhanced consumer perceived sensory sensations are provided which instill the consumer a perception of enhanced cleaning performance, and more particularly to a two component peroxide containing oral composition that provides enhanced sensory cues as well as providing a tooth whitening benefit.
2. The Prior Art
A tooth is comprised of an inner dentin layer and an outer hard enamel layer that is the protective layer of the tooth. The enamel layer of a tooth is naturally an opaque white or slightly off-white color. It is this enamel layer that can become stained or discolored. The enamel layer of a tooth is composed of hydroxyapatite mineral crystals that create a somewhat porous surface. It is believed that this porous nature of the enamel layer is what allows staining agents and discoloring substances to permeate the enamel and discolor the tooth.
Many substances that a person confronts or comes in contact with on a daily basis can "stain" or reduce the "whiteness" of one's teeth. In particular, the foods, tobacco products and fluids such as tea and coffee that one consumes tend to stain one's teeth. These products or substances tend to accumulate in the protein pellicle enamel layer of the tooth. These staining and discoloring substances can then permeate the enamel layer. This problem occurs gradually over many years, but imparts a noticeable discoloration of the enamel of one's teeth.
There are available in the marketplace oral compositions for home use which contain 1-3% by weight concentrations of a peroxide compounds such as hydrogen peroxide and when applied on the teeth effect whitening.
Illustrative of oral compositions containing peroxygen compounds for whitening teeth include U.S. Pat. Nos. 5,766,574 and 5,648,064.
U.S. Pat. No. 5,766,574 discloses dual component whitening dentifrice which comprises a first dentifrice component containing a peroxide compound such as urea peroxide and a second dentifrice component containing an abrasive such as alumina or silica which is incompatible with the peroxide, the first and second dentifrice components being maintained separate from the other until dispensed and combined for application to teeth requiring whitening.
U.S. Pat. No. 5,648,064 discloses a two component whitening dentifrice composition which discloses a first component containing a peroxygen compound such as hydrogen peroxide and a second dentifrice component containing a manganese coordination complex compound such as manganese gluconate, which activates the peroxygen compound and accelerates the release of active oxygen for rapid whitening action, the first and second components being maintained separate from the other until dispensed for application to teeth.
Further, it is known that bicarbonate-acid mixtures in toothpaste compositions will create an effervescent effect and that such effervescent effect can provide certain sensory and tooth cleaning benefits. For example, U.S. Pat. No. 5,885,871 discloses a two component effervescent dentifrice composition wherein the effervescent signal produced by the dentifrice derives form the evolution of carbon dioxide upon the mixing of a high alkaline pH paste (pH range 8-9) and a low acid pH (pH 2-4) gel.
There is an ongoing need for new and novel sensory benefits to promote the use of dentifrices and particularly in dentifrices used in the tooth whitening. | {
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This invention relates in general to acoustic wave sensors and in particular to a lateral field excited acoustic wave sensor.
Piezoelectric materials, such as crystalline quartz, generate an electric field or voltage when subjected to mechanical stress and, conversely, generate mechanical stress when subjected to an electric field or voltage. Accordingly, piezoelectric materials have proven useful in many diverse technologies. Typically, electrodes are deposited upon the surface of the crystal and an AC voltage is applied to the electrodes to generate an electric field in the crystal. The electric field, in turn, generates mechanical stresses in the crystal. If the applied AC voltage is at or near the resonant frequency of the crystal, a resonant acoustic wave is excited within the crystal. At the resonant frequency, which is determined by the cut angle, thickness, length, width and mass of the crystal, the acoustic wave may propagate and resonate within the crystal with very little loss.
A measure of how narrow a band of frequencies can be passed through a particular piezoelectric crystal with minimum attenuation relative to the resonant frequency of the crystal is referred to as the Q of the crystal. The Q of the crystal, which is a function of the crystalographic orientation of the crystal, determines the specific application for the crystal. For example, very low Q crystals are capable of converting wide frequency bands of mechanical energy to electrical energy; and, conversely, wide frequency bands of electrical energy to mechanical energy. Thus, low Q materials are often used as sonic transducers in microphones or speakers because the low Q allows many tones to be produced. With a very high Q material, only a very narrow band of frequencies may be passed through the crystal. Thus high Q material is typically used in devices that require highly accurate frequency control, such as oscillators.
High Q piezoelectric materials also are used in sensors. With modern manufacturing methods, precision crystals of quartz or other similar very high Q material may be made to oscillate at a frequency that is accurate to within a few parts per million or less. During production of such quartz resonators, layers of conductive electrode material may be deposited with a precision of a few atomic layers. The resonant frequency of the resulting resonators will be sensitive to extremely small changes in the mass of the electrodes. This characteristic sensitivity of high Q piezoelectric materials to changes in mass has led to a number of diverse sensor applications. For example, a quartz resonator may be coated with a sorbent which is selective to a particular compound. The amount, or concentration, of the compound can then be determined by monitoring the change in the resonant frequency of the quartz crystal as the compound is absorbed by the sorbent since, as the compound is absorbed, the mass of the sorbent and, hence, the total mass of the vibrating structure increases. Because the addition or subtraction of mass to the piezoelectric material results in a change of the resonant frequency of the crystal, such devices are commonly referred to as a Quartz Crystal Microbalances (QCM's) and are widely used in applications where a change in mass, density or viscosity is monitored, such as in sensing applications.
Referring now to the drawings, a typical known QCM sensor is illustrated generally at 10 in FIGS. 1 and 2. The sensor 10 includes a disc shaped substrate 12 of quartz having a diameter of approximately 25 mm. The standard crystallographic orientation used is an AT-cut since it is a temperature stable orientation in which only a Transverse Shear Mode (TSM) acoustic wave can be excited. Other orientations in quartz in which only a TSM acoustic wave can be excited also may be utilized. FIG. 1 shows the reference surface 14 of the substrate while FIG. 2 shows the sensing surface 16 of the substrate 12 that is opposite from the reference surface 14. A disc shaped reference electrode 18 formed from an electrically conducting material and having a diameter of approximately 6 mm is deposited upon the center of the reference surface 14. The electrode 18 is formed from an electrically conductive metal. The reference electrode 18 is connected by a first strip 20 of conductive material to an arcuate reference electrode tap 22. The reference electrode tap 22 allows electrical connection to an external sensing circuitry (not shown). The electrical connection is illustrated by a wire lead 24; however, the lead 24 is intended to be exemplary and other types of conventional electrical connections may be utilized.
As shown in FIG. 2, a disc shaped sensing electrode 26 formed from an electrically conductive metal and having a diameter of approximately 13 mm is deposited upon the center of the sensing surface 16. A second strip of conductive material 28 extends from the sensing electrode 26 to the edge of the sensing surface 16, transversely across the side of the substrate 12 and onto the reference surface 14, as shown in FIG. 1, where it ends in an arcuate sensing electrode tap 30. Similar to the reference electrode tap 22, the sensing electrode tap 30 allows electrical connection to the external sensing circuitry (not shown), as illustrated by a wire lead 32. Additionally, an adhesive layers 33 and 34 are typically deposited between the electrodes, 18 and 26, and the corresponding substrate surface, 14 and 16, respectively, to enhance adherence of the electrodes to the substrate surface. Finally, depending upon the application, a sorbent selective film (not shown) may cover the sensing surface 16.
During operation of the sensor 10, a variable frequency oscillator (not shown) is electrically connected to the reference and sensing electrode taps, 22 and 30, and the sensing surface 16 is inserted into an environment, which may be either a gas or a liquid, while the reference surface 14 remains exposed to air. The environment contains a measurand, which is a specific property of the environment that is being sensed by the sensor, such as, for example the concentration of a certain substance within a gas or liquid. Thus, when the sensing surface 16 is inserted into an environment, the sensing surface is exposed to a specific measurand contained within the environment. Should the sensing surface be covered by a sorbent film, the sorbent film also is immersed in the environment. The oscillator applies a varying voltage to the electrodes, 18 and 26, which then generate acoustic waves within the substrate 12. Such a mode of operation is referred to as Thickness Field Excitation (TFE). Before exposing the sensing surface 16 to the measurand the sensor 10 is calibrated by varying the oscillator frequency to resonate the sensor 10. The resonance frequency is detected and stored in a conventional device or circuit (not shown). After calibration, the sensing surface is inserted into the environment being monitored. The effect of mechanical loading properties of the measurand, such as mass, density and viscoelasticity, upon the sensing surface 16 causes the resonant frequency of the sensor to shift. The shift in resonant frequency can be calibrated to be indicative of the magnitude of a specific mechanical loading property of the measurand.
Alternate embodiments of the QCM sensor 10 having different sensing electrodes are illustrated in FIGS. 3 through 5. FIG. 3 illustrates small electrode geometry with a very small circular sensing electrode 35. A typical diameter for the sensing electrode 35 would be about 0.8 mm. In FIG. 4, a closed ring geometry sensing electrode 36 that has an aperture formed through the center of the electrode disc is shown, while FIG. 5 illustrates an open ring sensing electrode 38. The open ring electrode 38 is very similar to the closed ring electrode 36, except that the open ring electrode 38 has a slot 40 extending through the ring that corresponds to the tap region of the reference electrode. Both the closed and open ring electrodes 36 and 38 have an outside diameter of approximately 13 mm and an inside diameter of approximately 11 mm. All of the sensors shown in FIGS. 4 through 5 have a reference surface configuration that is similar to the sensor 10 shown in FIG. 1.
The use of conventional QCM sensors, such as the one shown in FIGS. 1 and 2, is limited to applications where measurand electrical properties such as permittivity and conductivity change in addition to changes in the mechanical properties listed above. In many applications, the measurement of changes in the electrical properties is critical. However, with conventional QCM sensors, such as the one shown in FIGS. 1 and 2, the sensing electrode 26 that contacts the measurand is the same size or larger than the reference electrode 18 that contacts air. Because of its size, the sensing electrode 26 shields most of the TSM electric field, preventing the penetration of the field into the measurand. Thus, a conventional QCM sensor has minimal sensitivity to changes in electrical properties of the measurand. The modified sensing electrode geometries shown in FIGS. 3 through 5 reduce the size of the sensing electrode. As a result, a small shift of the resonant frequency of the modified QCM sensors may be detected as the electrical properties of the measurand changes. However, it is desirable to provide a piezoelectric sensor with greater sensitivity to the mechanical and electrical properties of the measurand. | {
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In order to efficiently utilize wireless access techniques such as Worldwide Interoperability for Microwave Access (WiMAX) to cover an area, wireless network planning and optimization are necessary to determine the optimal base station site, in accordance with factors such as geographic environment and wireless channel propagation environment of the area. FIG. 1 is a schematic diagram illustrating the base station site in Beijing by using wireless access techniques.
Similarly, in order to efficiently utilize wired access techniques such as Asymmetric Digital Subscriber Loop (ADSL) to cover the same area, such as Beijing, as illustrated in FIG. 2, wired network planning and optimization is also necessary to determine the optimal site of the wired device in accordance with factors such as geographic environment and wired channel propagation environment of the area.
The technical solution of the prior art is as follows:
Two access networks are constructed respectively, i.e., a wired access network such as Digital Subscriber Loop (DSL) broadband access network and a wireless network such as WiMAX cellular access network. The wired access network is optimized with the wired access network optimization method, and the wireless access network is optimized with the wireless access network optimization method.
It can be seen from the technical solution of the prior art:
If Carrier A firstly constructed a wired access network covering an area by utilizing wired access techniques, and then constructed a wireless access network covering the same area by utilizing wireless access techniques. Or in the other case, i.e., Carrier B firstly constructed a wireless access network covering an area by utilizing wireless access techniques, and then constructed a wired access network covering the same area by utilizing wired access techniques. As described before, in wireless network planning and wired network planning, optimal sites selection is performed in accordance with their own access techniques respectively, so it may result in difference between the site of an original network device and the optimal site of a newly-added network device. Referring to FIG. 3, the differences between the optimal sites of the original wired devices/wireless Base Stations (BSs) and the optimal sites of the newly-added wireless BSs/wired devices can be up to several kilometers. Therefore, there exists an issue in the prior art that the site selection for the wired devices/wireless BSs of the original network is in contradiction to the site selection for the wireless BSs/wired devices of the newly-added network.
The optimal sites of the wired devices/wireless BSs of the original network are different from the optimal sites of the wireless BSs/wired devices of the newly-added network, and in the prior art, the original network and the newly-added network are independent of each other, so resources can not be efficiently utilized. For example, in the prior art, both the BSs of the wireless access network and the wired devices of the wired network are supplied with AC power supply, and are provided with backup power supplies by using battery pack, Un-interruptible Power Supplies (UPS), power generation set or the second mains power; cable resources of the wireless access network and the wired access network can not be efficiently utilized; and operators usually need to take the land on lease and construct machine-rooms for the BSs of the wireless access network and the wired devices of the wired access network respectively.
Furthermore, it is difficult to uniformly maintain the BSs of the wireless network and the wired devices of the wired network, which can result in high maintenance cost. | {
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The present invention relates to a video signal compression apparatus for compressing component portions of a video signal according to compression ratios specific to each component which depend upon the frequency with which the particular component appears in the video signal.
During ordinary operation of a video camera system, the quantity of light incident upon the imaging device varies by several orders of magnitude. To facilitate the storage and reproduction of images comprised of such a range of light intensities, video signal compression techniques are employed to reduce the amount of information needed to represent such images.
In the art, an apparatus for compressing the intensity or luminance level of a video signal is referred to as a "knee circuit." Several examples of prior art knee circuits are described in U.S. Pat. No. 5,357,279, Nakamura et al., which is also assigned to the assignee of the present application. Typically, a knee circuit processes an input video signal according to the fixed transfer function illustrated in FIG. 1. According to this function, output video level varies with input video level at a first constant rate until the single "knee point" is reached. The "knee point" is simply the input video level at which the transfer function changes. After the knee point, output video level varies with input video level at a second constant rate, wherein the second constant rate is less than the first constant rate.
Upon study it has been determined that the frequency with which a particular input video level occurs is not necessarily proportional to the input video level. For example, as illustrated in the histogram of FIG. 2, the distribution of input video levels may be generally concentrated around two particular input video signal levels. In this figure, the y-axis represents the number of occurrences while the x-axis represents input video intensity level. The number of occurrences preferably refers to the number of imaging elements, e.g. pixels, which register a particular intensity or luminance level in a given input image.
Application of the fixed transfer function described above to the input image represented by FIG. 2 clearly yields an inefficient allocation of the output video signal. According to such a compression scheme, input video levels are compressed at one of two different rates regardless of the actual frequency with which a particular input video level occurs. Consequently, some input video levels are unnecessarily excessively compressed while other input video levels are allocated too much of the output video signal and thus are compressed by a less than optimum amount. | {
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a) Field of Invention
The invention concerns a cassette loading facility for a cassette device for the recording and/or reproduction of information.
Such a cassette loading facility can be used with any audio and video device in which a storage medium for the recording and/or reproduction of information, such as a magnetic tape, magnetic disk or similar, is inserted in a cassette.
b) Description of the Prior Art
With a commercially available video recorder, for example, such a cassette loading facility essentially consists of a guide frame mounted on the drive chassis in a fixed position and a driveable cassette receiving facility which is guided in the guide frame in such a way that it can be moved between a cassette loading position and a cassette operating position. In the loading position the cassette can be inserted into or removed from the receiving facility. In the operating position the tape winding, or rather the two reel hubs of a cassette, engage with the driveable winding spindles of the drive chassis. The reel hubs are mounted in the cassette so that they may move. For the purpose of positioning the cassette relative to the plane of the chassis, catch apertures are built into the drive side of said cassette which are brought into engagement with corresponding positioning pins located on the chassis.
With such a recorder in which a cassette, for example, can be inserted through a corresponding opening in the front of the housing for the device or removed therefrom after completion of a recording, playback or rewinding operation, the loading procedure is characterized essentially by a movement of the cassette receiving facility parallel (horizontal) to the drive chassis as well as a movement perpendicular to the drive chassis. In doing this, the cassette located in the receiving facility is normally held frictionally engaged with the help of leaf springs mounted on the receiving facility. However, there is a disadvantage connected with this in that owing to the high frictional engagement forces required for holding the cassette, relatively high manual forces must be exerted in order to insert the cassette into the receiving facility or to draw it out from this. Apart from that, a precise positioning of the cassette within the receiving facility during the loading procedure is not guaranteed by the frictional engagement so that an additional orientation with the positioning pins is necessary.
A cassette loading facility is known from the patent specification DE 37 07 830 in which, to avoid the above disadvantages, the cassette receiving facility has an arresting device with a catch block which, upon feeding in a cassette, clips into a recess in the cassette in a form-fit manner so that the cassette is arrested during the entire loading procedure. The recess in the cassette is formed in the housing side of such a cassette which faces away from the drive. However, this arresting device is only applicable under certain conditions because the cassettes of other system standards, for example, the VHS standard, do not have such a recess on the side facing away from the drive. | {
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Optical plastic discs are a commonly used medium for storing large amounts of information. Optical plastic disc formats include such consumer products as laser discs, compact discs, and digital video discs (DVD).
A proven method of reproducing optical plastic discs is via injection molding. In order to reproduce optical plastic disc via injection molding, a very clean environment and precision equipment is necessary.
Typically, information from a premaster tape is first transferred to and stored on a glass master disc. The glass master disc has a series of microscopic pits and flat areas spiraling from the center of the disc. These pits and flat areas represent the information stored on the glass master disc which is to be reproduced on a metal disc called a "stamper.". The (positive) glass master disc is typically used to create (negative) stampers. The stamper is placed onto a set of mold dies. Mold dies consist of a male metal circular plate and a female metal circular plate, and they are polished to a mirror surface quality. These molds with a stamper create a shell into which molten plastic can be injected for production of optical plastic discs.
During the production process, it is essential to keep the inside surfaces of the mold dies very clean and free of dust and other contaminants, so an operator of an injection molding machine must thoroughly and carefully clean the inside surfaces of the molds whenever the machine is stopped for any reason. Conventional methods of cleaning the surface of a mold are time consuming. Currently, acetone is typically used as a cleaning agent. However, using acetone has several drawbacks including that it produces hazardous fumes and is toxic to humans. Also, currently, relatively expensive gauze-like cloth is used to wipe the molds in the cleaning process. However, when using such cloth, extra care must be taken and skill is required so as not to damage the surface of the mold.
Moreover, the density of the pits and surfaces which stores information on the optical plastic discs continues to increase as technology moves on. For example, the density of pits and surfaces of DVD discs are greater than that of compact discs. This increasing density means that the production process becomes more sensitive to contaminants on the mold dies. | {
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Vehicles serve as a common form of transportation utilized by many. Often, vehicle usage can lead to road congestion. Vehicle operators are required to stay focused on the vehicles ahead of them as well as road conditions. In some circumstances, a distracted individual may cause an accident that could result in vehicle damage, traffic jams, and/or injury or death.
As hand-held devices have evolved, more individuals have become accustomed to always being virtually connected. Additionally, vehicles have experienced an increased prevalence of sensors capable of sensing and generating data associated with vehicle operators and their operation. However, even with this increasing prevalence, there are no existing solutions for determining when specific drivers are operating vehicles in certain situations. For example, there is no existing solution for determining when a vehicle operator may be distracted. Accordingly, there is an opportunity for systems and methods to leverage various data to determine when vehicle operators may be distracted, and accordingly facilitate certain actions to mitigate the risks posed by the distracted vehicle operators. | {
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Polyimide resin has excellent heat resistance, an excellent electrical insulating property, excellent chemical resistance, and a mechanical property, and therefore is used for electric and electronic purposes. For example, the polyimide resin is used as materials of (i) an isolation film and a protective coating agent provided on a semiconductor device, (ii) a surface protective material and a base material resin for a flexible circuit substrate, an integrated circuit, and the like, and (iii) an interlayer insulating film and a protective film for a fine circuit. Particularly, in a case where the polyimide resin is used as a coating material for wiring lines on a substrate, the polyimide resin is used in a form of, for example: a cover lay film that is obtained by applying an adhesive agent on a shaped product such as a polyimide film; or a liquid cover coat ink made from the polyimide resin and the like.
As the polyimide resin solution used as the liquid cover coat ink, there have been proposed, for example, a polyimide resin soluble in an organic solvent and a polyimide resin composition using a thermosetting resin such as epoxy resin (see, for example, Patent Literatures 1 to 4).
Further, there has been proposed a curable imide resin composition in which a low-molecular-weight amide-imide resin having a carboxyl group and/or a low-molecular-weight imide resin having a carboxyl group, and an epoxy resin are dissolved (for example, see Patent Literature 5).
Further, there has been proposed a curable resin composition containing an epoxy resin and an imide oligomer having an acid anhydride group at its terminal, which imide oligomer is obtainable from an asymmetric aromatic or cycloaliphatic tetracarboxylic acid dianhydride and diamino polysiloxane (for example, see Patent Literature 6). | {
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Known card feeding systems in a card handling device may include a support surface with pick-off roller(s) that are located within the support surface to remove one card at a time from the bottom of a vertically oriented stack of cards. In this orientation, each card face is in a substantially horizontal plane with the face of a card contacting a back of an adjacent card. The weight of a stack of cards ordinarily provides a sufficient force against the rollers to assure proper movement of most of the cards. But as the stack size decreases after most of the cards have been delivered, the weight of the cards may no longer be sufficient, especially with the last few remaining cards in the stack to assure proper movement of the cards.
U.S. Pat. No. 5,692,748 to Frisco et al. describes a card shuffling device containing free-swinging weights on pivoting arms that applies pressure to the top of stacks of cards that are to be mixed. The lowest card in each stack is in contact with a feed roller that propels the card horizontally, one at a time into a center mixing chamber. As described in Frisco, each of the first and second chambers 34, 36 has an arm 52 pivotally mounted at one end by a pivot 54 to the housing 12 and having at the other end a foot 56. As described therein, when cards are cut and deposited into the first and second chambers 34, 36, the arms 52 pivot as the cards 30 are urged over the front barriers 42 into their nested positions in the first and second chambers 34, 36. As nested on the floors 40 of the first and second chambers 34, 36, the arms 52 remain in contact with the top of the cards 30 to impose a vertical load on the cards 30 to urge them to be contacted by the wheels 48a, 48b. Proximate the foot 56 of each arm 52, a weight 58 is provided on each of the arms 52. These weights on pivoting arms apply pressure through the stack(s) of cards to assure traction against a pick-off roller at the bottom of the stack.
U.S. Pat. Nos. 6,655,684, 6,588,751, 6,588,750 and 6,149,154 to Grauzer et al.; U.S. Pat. Nos. 6,568,678 and 6,325,373 to Breeding et al.; and U.S. Pat. No. 6,254,096 to Grauzer describe a shuffler having a “free-floating,” rolling weight that slides along a declining card support surface, toward a set of feed rollers to provide increased force on the rollers to assist in advancing cards. The references also disclose sensors for detecting the presence of cards in a delivery tray or elsewhere.
U.S. Pat. No. 6,637,622 to Robinson describes a card delivery device with a weighted roller for assisting in card removal. A weighted cover is provided on the delivery end of the dealing shoe, covering the next card to be delivered.
U.S. Pat. No. 5,722,893 to Hill et al. describes the use of a weighted block for urging cards toward a discharge end of a shoe. The block provides a force against the cards. The block triggers a sensor when the shoe is empty. The reference specifically states: “In operation, a wedge-shaped block mounted on a heavy stainless steel roller (not shown) in a first position indicates that no cards are in the shoe. When the cards are placed in the shoe, the wedge-shaped block will be placed behind the cards and it and the cards will press against the load switch.”
U.S. Pat. No. 5,431,399 to Kelley describes a bridge hand forming device in which cards are placed into an infeed area and are randomly distributed or distributed in a predetermined manner into four separate receiving trays. A weight is shown placed over the cards in the infeed area.
It would be desirable to provide structures and methods to apply a force to individually fed cards to assure consistent feeding, but only when the weight of the stack of cards is insufficient to provide adequate contact with the card feeder to consistently feed cards. It would be desirable for such a mechanism to be retractable as to not interfere with card loading. It would also be desirable to provide a structure and methods that assist in temporarily retaining cards in a position that enables consistent and accurate card handling. | {
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1. Field of the Invention
This invention relates to an optical input device for a digital computer or terminal, but more particularly to a device made up of optical fibers forming a matrix to receive a light beam to indicate the position of the light beam as moves relative to the input device.
2. Description of the Prior Art
Prior art input devices include the mechanical mouse which involve wheels or rollers which maintain frictional contact with a surface. There are certain mechanical problems which are inherent with these mice, such as the problem in maintaining good frictional contact with a surface. If a mechanical mouse encounters a slippery portion of a surface, the resulting output signal will be inaccurate. Furthermore, a mechanical mouse uses a relatively large number of close tolerance parts and is difficult to make in mass production. Moreover, it is subject to mechanical "noise", such as lash and vibration, and requires frequent cleaning.
Another prior art input device is the joy stick control which includes a level, usually connected to a bearing. As the lever is moved and the bearing is rotated correspondingly, the bearing motion is sensed by potentiometers corresponding to different directions of bearing rotation. The output signal from a joy stick may be used for the same purpose as the output signal from a mouse. Both may be used to control a cursor. The distinguishing feature of a mouse is that two-dimensional motion over a surface corresponds directly with two-dimensional motion of a cursor in a graphic display.
More recently, optomechanical mice have been employed. As is the case with the mechanical mouse, the optomechanical mouse rolls a track ball over a surface in sense movement. Unlike the mechanical mouse, however, it incorporates optical encoders to measure distance. In the optical system, a shaft couples the movement to optical discs that interrupt a light beam as the ball moves. The design of the encoder wheel determines the resolution of the device.
More recently, optical mice have been used to input digital computers. This device must move over a pad with a special checker-board-pattern surface to gauge motion. The mouse contains one or two light-emitting diodes whose light shines onto the checker-board-pattern as the mouse moves. A mirror in the mouse shines light reflected from the surface into a light detector. The detector translates the light patterns into pulse trains that indicate motion. That indication of motion controls a cursor.
The fiber optics input device has advantages over any of these prior art devices:
1. There is no physical contact needed to activate the device and therefore there is no contact wear.
2. The fiber optics input device provides a non-electrical pad that is insensitive to electromagnetic and radio frequency fields, has a wide transmission bandwidth with low transmission loss, and eliminates any danger of combustion or sparking.
3. It is simple in design and therefore is of lower cost.
4. It is highly reliable.
5. It may be isolated in a hostile environment, including explosive fumes, high temperature, and high humidity.
6. It may be structured to measure distance from the light source to the device. | {
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1. Field of the Invention
The present invention relates to a power supply device that supplies power to an electrical load such as a motor, and a method for driving the same.
2. Description of the Related Art
(Explanation of a Power Supply Device for which the Present Invention is Useful)
A known example of a power supply device is shown in FIGS. 8A to 8F. A power supply device 80 of FIG. 8A is a device for supplying power to a motor M. The power supply device 80 is provided with a series circuit A in which two switching elements A1 and A2 are connected in series and a series circuit B in which two switching elements B1 and B2 are connected in series. The series circuits A and B are connected in parallel. The aforesaid parallel circuit is connected between a pair of terminals, c and d, of a direct current power source S. An intermediate electric potential point a between the switching elements A1 and A2 of the series circuit A is connected to one of the power supply points of the motor M. An intermediate electric potential point b between the switching elements B1 and B2 of the series circuit B is connected to the other power supply point of the motor M.
FIG. 8B shows a state in which power is supplied to the motor M, wherein the switching elements B1 and A2 are in an on-state, and the switching elements A1 and B2 are in an off-state. In this case, current is supplied to the motor M in the direction indicated by an arrow. FIG. 8E shows another state in which power is supplied to the motor M, wherein the switching elements A1 and B2 are in the on-state, and the switching elements B1 and A2 are in the off-state. In this case, current is supplied to the motor M in the direction indicated by an arrow. The power supply device 80 is able to switch the direction in which the power is supplied to the motor M.
FIG. 8A shows an intermediate stage of switching from FIG. 8B to FIG. 8E. In FIG. 8A, the switching element A2 that had been in the on-state in FIG. 8B is switched to the off-state. Subsequently, as a result of the switching element B1 being switched off and the switching elements A1 and B2 being switched on, the state is switched to the state shown in FIG. 8B. The states of those switching elements that are switched between the on-state and off-state are indicated in boxes to facilitate easy understanding.
Upon switching from the state shown in FIG. 8B to the state shown in FIG. 8A when the current flowing to the motor M suddenly becomes zero, a high voltage is generated due to a reactance component of the motor M. It is possible that this high voltage destroys the switching elements A1, A2, B1 and B2 by acting thereon. In order to avoid this, a diode is connected in reverse parallel to the switching element A1. When a diode is connected in reverse parallel to the switching element A1, the motor current continues to flow as indicated by an arrow of FIG. 8A, thereby making it possible to prevent the high voltage from acting on the switching elements A1, A2, B1 and B2. The diode connected in reverse parallel to the switching element is referred to as a return diode, and current that continues to flow even after the switching element A2 has switched to the off-state is referred to as a return current. The return diode is required to have a low forward voltage drop.
As shown in FIG. 8A, when the state of FIG. 8E is realized by switching the switching element A1 to the on-state under a condition in which the return current is flowing to the return diode connected in reverse parallel to the switching element A1, a reverse recovery current flows to the return diode to which the aforesaid return diode has flown. When a large reverse recovery current flows, a high voltage is imposed on the switching elements A1, A2, B1 and B2, resulting in the possibility of damage thereof. A technology is required that reduces the reverse recovery current that flows to the return diode to a low level.
The description above has provided an explanation of the return current that flows when the state of FIG. 8B is changed to the state of FIG. 8E through the state of FIG. 8A. However, situations in which the return current flows are not limited thereto.
A technology is known for regulating a root-mean-square (RMS) current supplied to the motor M by repeatedly switching between the state of FIG. 8B and the state of FIG. 8A. If the duration of the state of FIG. 8B is long and the duration of the state of FIG. 8A is short, a large current passes through the motor M. If the duration of the state of FIG. 8B is short and the duration of the state of FIG. 8A is long, a small current passes through the motor M. The return current also flows when realizing the state in FIG. 8A in order to control electric current.
RMS current supplied to the motor M can be adjusted sinusoidally by repeatedly switching between the state of FIG. 8B and the state of FIG. 8A. The direction of current supplied to the motor M can be inverted by switching between the state of FIG. 8B and the state of FIG. 8E. Combination of the aforesaid two makes it possible to apply alternating current to the motor M. The power supply device 80 can also be said as a conversion device that converts a direct current to an alternating current.
When switching from the state of FIG. 8A to the state of FIG. 8B, the reverse recovery current flows to the return diode to which the return current had previously been flowing. When such a large reverse recovery current flows, a high voltage acts on the switching elements A1, A2, B1 and B2 resulting in the possibility of the destruction thereof. A technology is required that reduces reverse recovery current flowing to the return diode to a low level.
In the case of switching the current direction by switching from the state of FIG. 8B to the state of FIG. 8E, the state of FIG. 8B may be switched to the state of FIG. 8E via the state of FIG. 8C. Switching between FIG. 8B and FIG. 8C may alternately be repeated to control the electric current. In the case of FIG. 8C, the return current flows to a return diode connected in reverse parallel to the switching element B2.
In the case of changing the current direction by switching from the state of FIG. 8E to the state of FIG. 8B, FIG. 8E may be switched to FIG. 8B via the state of FIG. 8D; alternately, FIG. 8E may be switched to FIG. 8B via FIG. 8F. In order to control the electric current, FIG. 8E and FIG. 8D may be switched repeatedly, and FIG. 8E and FIG. 8F may alternately be switched repeatedly. In the case of FIG. 8D, the return current flows to a return diode connected in reverse parallel to the switching element B1, and in the case of FIG. 8F, the return current flows to a return diode connected in reverse parallel to the switching element A2.
In any case, the return diode is required to have a low forward voltage drop, and it is necessary to reduce the reverse recovery current that flows to the return diode to a low level.
FIGS. 9A to 9I, 10A to 10I and 11A to 11I indicate examples of power supply devices for a three-phase motor. In each of these power supply devices, phase of current passing through the motor M can be switched by switching in the order of B, E and H of each drawing. During switching of the phase, the state switches to the state of A or C, D or F, or G or I of each drawing. Alternatively, the state switches to the state of either: A or C, D or F, or G or I of each drawing to adjust the RMS current magnitude that passes through the motor M. When switching to the state of A or C, D or F, or G or I of each drawing by switching off a switching element that had previously been on, the return current flows to the return diode. The switching elements are protected from the high voltage acting thereon by directing the return current to flow to the return diode. In any of these power supply devices, since the return current flows to the return diode when switching to the either state of A or C, D or F, or G or I as in the respective drawing, the return diode is required to have a low forward voltage drop. Since the reverse recovery flows to the return diode in any of the power supply devices when switching to either state of B, E or H from A or C, D or F, or G or I of each drawing, it is necessary to reduce the reverse recovery order to a low level.
In any of the power supply devices of FIGS. 9A to 9I, 10A to 10I and 11A to 11I, a three-phase alternating current is provided to the motor M by combining switching of the current direction and adjustment of the RMS current. All of these power supply devices are conversion devices that convert direct current to the three-phase alternating current.
All of the power supply devices shown in FIGS. 8A to 8F, 9A to 9I, 10A to 10I and 11A to 11I are each provided with switching elements and composition circuits connected in reverse parallel to the switching element. In each of these power supply devices, the plurality of composition circuits are connected in series, and a plurality of such series circuits are connected in parallel. The aforesaid parallel circuit is connected between a pair of power supply terminals, and intermediate electric potential points between the composition circuits of each series circuit are connected to a load. The power supply devices provide electric power from a power source to the load. The power supply devices switch the direction in which power is supplied to the load, or adjust the amount of the RMS current supplied to the load.
The plurality of switching elements switches states according to the following rules:
(1) a switching element on one side of an intermediate electric potential point of one series circuit is switched to the on-state;
(2) a switching element on another side of the intermediate electric potential point of the series circuit of (1) above is switched to the off-state;
(3) a switching element on one side of an intermediate electric potential point of at least one of the other series circuits is switched to the off-state; and,
(4) a switching element on another side of the intermediate electric potential point of the series circuit of (3) above is switched to the on-state, so that electric power is supplied from the power supply to the load via the two switching elements switched to the on-state of (1) and (4).
In the case of FIG. 9B, for example, C1 is switched on according to (1), C2 is switched off according to (2), both A1 and B1 are switched off according to (3), and both A2 and B2 are switched on according to (4). In the case of FIG. 10B, C1 and B1 are switched on according to (1), C2 and B2 are switched off according to (2), A1 is switched off according to (3), and A2 is switched on according to (4). In the case of FIG. 11B, C1 is switched on according to (1), C2 is switched off according to (2), A1 is switched off according to (3), and A2 is switched on according to (4). In the case of FIG. 11, both B1 and B2 are switched off according to (1), (2) and (3) respectively.
In the case of FIGS. 9 and 10, one switching element can be in the on-state on one side while two switching elements can be switched to the on-state on another side, or two switching elements can be in the on-state on one side while one switching element is switched to the on-state on another side. As shown in FIG. 11, the electric power can be supplied to the load if a switching element on aforesaid another side is switched on in at least one series circuit that differs from a series circuit in which a switching element on one side is switched on.
In this type of power supply device, the direction in which electric power is supplied to the load can be sequentially switched by sequentially changing the series circuit in which a switching element on one side is to be switched to the on-state according to (1) above. In the case of FIGS. 9 and 10, a rotating magnetic field can be created in the three-phase motor M by switching in an order of B, E and H.
When a switching element having been switched to the on-state according to (1) above is switched to the off-state, the return current flows to the return diode connected in reverse parallel to a switching element according to (2) above.
In the case of FIG. 8, when A2 switched on in FIG. 8B is switched off, as to the state of FIG. 8A, the return current flows to the return diode connected in reverse parallel to the switching element A1 as in (2) above. If B1 switched on in FIG. 8B is switched off to the state of FIG. 8C, the return current flows to the return diode connected in reverse parallel to the switching element B2 as in (2) above.
In the case of FIG. 9, when C1 switched on in FIG. 9B is switched off to the state of FIG. 9A, the return current flows to the return diode connected in reverse parallel to the switching element C2 as in (2) above. When A2 and B2 switched on in FIG. 9B are switched off to the state of FIG. 9C, the return current flows to the return diodes connected in reverse parallel to the switching elements A1 and B1 as in (2) above respectively.
In the case of FIG. 10, when B1 and C1 switched on in FIG. 10B are switched off to the state of FIG. 10A, the return current flows to the return diode connected in reverse parallel to the switching elements B2 and C2 as in (2) above. When A2 switched on in FIG. 10B is switched off to the state of FIG. 10C, the return current flows to the return diode connected in reverse parallel to the switching element A1 as in (2).
Although the power supply devices of FIGS. 8A to 8F, 9A to 9I, 10A to 10I and 11A to 11I can also be configured by using a composition circuit combining a switching element and a diode, a power supply device can also be produced by combining semiconductor devices in each of which an IGBT domain and a diode element domain coexist in a same semiconductor substrate. The semiconductor device in which the IGBT domain and the diode element domain coexist in the same semiconductor substrate is referred to as a reverse conducting semiconductor device.
(Characteristics Required of Power Supply Device)
If the forward voltage drop of the return diode is large, a constant loss increases and the return diode generates heat. The return diode is required to have a small forward voltage drop. The amount of the voltage drop of the return diode can be decreased by increasing impurity concentrations of an anode and a cathode.
On the other hand, the reverse recovery current flows to the return diode. If the impurity concentrations of the anode and the cathode of the return diode are increased in order to decrease the forward voltage drop, a reverse recovery loss of the return diode increases. If the impurity concentrations of the anode and the cathode are increased, a large quantity of p-type carriers accumulate in the cathode and a large quantity of n-type carriers accumulate in the anode when a forward voltage is applied. When a reverse voltage is applied to the return diode, i.e., when the cathode is connected to a high electric potential side and the anode is connected to a low electric potential side, the p-type carriers within the return diode flow in the direction of the anode, while the n-type carriers flow in the direction of the cathode, thereby resulting in the flow of reverse recovery current. In the case of increasing the impurity concentrations of the anode and the cathode, the quantity of p-type carriers that accumulate in the cathode and the quantity of n-type carriers that accumulate in the anode increase, resulting in the flow of large reverse recovery current. If such a large reverse recovery current flows, a large amount of heat is generated, and electric power is consumed. Moreover, in the case where the current amount exceeds a permissible current of the diode, the return diode is destroyed. By lowering the impurity concentrations of the anode and the cathode, the reverse recovery current can be held to a low level and the reverse recovery loss can be reduced, however, the forward voltage drop as a result becomes large.
Both the constant loss and the reverse recovery loss of the return diode cannot be decreased even by tuning the characteristics of the return diode.
Japanese Patent Application Publication No. 2005-317751 (steady-state 1) discloses a technology that uses a lifetime control to reduce the reverse recovery loss. According to this technology in the aforesaid patent document 1, a low lifetime layer is formed on an impurity injection domain corresponding to the anode and/or the cathode. In the case the low lifetime layer is formed on the cathode, the quantity of p-type carriers that have accumulated in the cathode dissipates in a short period of time after completion of the application of a forward voltage. Similarly, in the case the low lifetime layer is formed on the anode, the quantity of n-type carriers that have accumulated in the anode dissipates in a short period of time. As a result, the reverse recovery current can be decreased, and the reverse recovery loss can be reduced. | {
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A light-detection technique may count individual photons to measure intensity of light (e.g., a single photon counting (SPC) technique). For example, incident photons may be counted individually over a period of time to obtain a measurement of light intensity and/or flux during an imaging operation.
A delay (e.g., a dead-time) may be created after a photon is received until a circuit (e.g., a light-detection circuit) is ready to receive another photon. The delay may limit an upper photon count rate, making the light-detection technique unsuitable in an application requiring high-speed processing and/or high dynamic range imaging (e.g., a biomedical application, a military application, a nighttime imaging operation, a low light imaging operation).
Reducing the delay using faster transistors may result in increase of a dark count (noise) due to an afterpulsing effect. A reduction of the delay through operating the circuit at a low bias voltage may decrease a probability of detecting a photon detection of the circuit. A decrease in the probability of detecting the photon may reduce the sensitivity of the circuit. A decrease in sensitivity may lead to an inaccuracy in photon count. Consequently, the light detection circuit may not perform efficiently in high sensitivity and high speed applications. | {
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1. Field of the Invention
This invention relates to the field of variable reluctance (VR) electric motors, also called stepper motors, for high torque applications.
2. Description of the Prior Art
Variable reluctance motors (VR motors) are typically used as stepper motors because they can produce rotation in small, discrete steps. This mode of operation is inherent in the nature of VR motors. VR motors have a multi-pole rotor, with the separation between poles on the stator, the pitch, different from that on the rotor. The stator poles are electromagnetically excited in separate groups or phases and the rotor rotates until its poles reach a position of minimum magnetic reluctance relative to the excited stator poles. Upon energizing successive stator phases, the rotor turns a distance equal to the rotor pitch minus the stator pitch.
Other characteristics of variable reluctance motors including their low cost, small size and high torque-to-inertia ratio make VR motors attractive for use as general purpose servomotors. Their brushless construction makes VR motors particularly suitable for applications requiring spark-free operation.
However, two drawbacks have limited the use of variable reluctance motors as servomotors: torque ripple and a nonlinear torque to input current ratio (T/I). Torque ripple is the variation in maximum available output torque as the position of the rotor poles varies with respect to the stator poles. The nonlinear T/I ratio is inherent in the design of typical VR motors because they have no permanent magnets. Torque is created by the interaction of two magnetic fields, the rotor field and the stator field, both a function of current.
In the past, in order to optimize the torque characteristics of VR motors, the stator has been the determinative element in designing the motor. Stator design balanced magnetic flux leakage, caused by having too many teeth too close together, against minimum holding torque at the stable detent position, caused by having too few teeth. The stator was designed with many teeth of uniform cross section, to provide the maximum practical area at the tips of the teeth for the magnetic flux, while maintaining sufficient intertooth space for the winding coils. The ratio of the width of the stator teeth to the width of the gap between the teeth, called the stator tooth ratio, was typically 1.0 or more. The rotor design was dependent on the stator design, with the number and width of the rotor teeth chosen to suit the geometry of the stator. The ratio of the width of the rotor teeth to the width of the gap between the teeth, called the rotor tooth ratio, was about 0.5.
One improvement on the above-described VR motors is disclosed by Konecny in U.S. Pat. No. 4,647,802, filed June 13, 1985 and issued Mar. 13, 1987.
Konecny discloses as shown in FIG. 1 making the rotor 32 rather than the stator 30 the determinative element in the design and incorporating a tapered stator tooth 31 configuration. Rotor tooth 39 is untapered. The rotor 32 is mounted on shaft 33. The rotor tooth width ratio rather than the stator tooth ratio is the basis for optimizing torque characteristics, resulting in a larger rotor tooth ratio than in the prior art of about 0.78 and a smaller stator tooth ratio than in the prior art of about 0.5. The stator 30 has fewer teeth than the rotor 32, and the stator teeth 31 are tapered so they are wider at the base 37 than at the tip 31. Konecny uses just one stator tooth 31 per pole.
Another improvement is disclosed by Gordon et al. in U.S. Pat. No. 4,496,886, filed Nov. 8, 1982 and issued Jan. 29, 1985. Gordon et al. disclose a three-state driver for the stator winding of a variable reluctance motor. The driver allows a desired current level to be achieved with only a minimum of current ripple. | {
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The present invention concerns a laser, particularly a CO.sub.2 gas transport laser with several discharge tube sections attached in mounts and accommodating the flow of laser gas.
Under this main concept, reference is made to the state of the art known, e.g., from German DE-OS No. 27 41 737. In this known laser, the discharge tube sections are connected over the mount in such a manner that the tube sections provide a nonfolded discharge tube, at the beginning and end of which laser mirrors are provided. The supply lines for the laser gas as well as the discharge lines for the laser gas are located beside the mounts and are, accordingly, led past the mounts and the discharge tube sections. This causes a complicated structure of the laser, particularly when there are more than two discharge tube sections and a corresponding number of mounts.
Investigations and research concerning CO.sub.2 gas transport layers have led to the recognition that an increase of the laser performance can be achieved if several short, optimum discharge tube sections are coupled in series, whereby each discharge tube section has its separate power and gas supply or gas discharge. An arrangement of this type can also be advantageously used for pulsation of laser beams. For instance, if four discharge tube sections of this type would be correspondingly coupled in series in the five required mounts, thus in a sense, four laser modules after one another, a laser effect of more than 1 KW can be obtained with the corresponding dimensions and design of the laser tubes and with sufficient gas supply, with a total discharge tube length (discharge tube sections) of approximately 1 m.
On the basis of the initially mentioned state of the art, a laser design would emerge where, although the total length can be relatively short, the volume will be large, considering the gas supply and gas discharge lines that are to be provided. As a result, the total laser become unwieldy and, in particular, it cannot be assembled without problems as a mobile processing tool on a guide machine, e.g., for cutting of materials. | {
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Unless otherwise indicated herein, the materials described in this section are not prior art to the claims in this application and are not admitted to be prior art by inclusion in this section.
Various components of a traditional computer system may be integrated into a single integrated circuit (IC). The IC may comprise several regions that are each dedicated to a specific functionality, such as a memory controller (MC) region and a double data rate (DDR) input/output (I/O) region. Data may be transmitted from the MC region to the DDR I/O region via, for example, flip-flop based FIFOs or shift registers. The two regions may operate under the same clock frequency. However, for various reasons, the clocks of the two regions may originate from different clock sources, e.g., different Phase Locked Loop (PLL) clock sources. Under certain circumstances, the clock skews between the two regions may be greater than 50% of each clock cycle. In order to accommodate the clock skew, additional setup and hold time tolerance may be required for the flip-flop based FIFOs to transfer data between the two regions in a consistent manner. The increased setup and hold timing requirements may cause extra delay in the path of data transmission, which may be undesirable, especially if the data transmission between the two regions is latency critical.
Furthermore, the two regions of the IC may operate under different voltage levels. As such, data may need to be level-shifted after entering the receiving region. Level-shifting the data using separate circuit blocks may further increase the delay. | {
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The present invention relates to a tidy element divided into several compartments suitable for keeping small items that are of common use and are taken away by business men and/or students, for example office requisites, such as writing instruments, drawing instruments and mathematical instruments, pencils, fountain-pens, ball-point pens and the like, notebooks, notepaper, postage-stamps, small documents to be distributed or to be kept, such as visiting cards, small working items, such as pocket calculators, pocket diaries, magnetic recorders in miniature, as well as small-sized items to be taken away that could easily go astray in a tidy element of large volume. Said tidy element is specially designed to be fitted inside the back of a case of the attachecase type and to be secured to the back of the case, i.e. to the inner face of the opening lid of such a case, the tidy element being essentially characterized in that it is designed in such a way as to allow to find easily very small items contained therein and in that, although it is of a little thickness, it may contain rather numberous articles that will be easily found again to be used, the lids with which certain compartments are provided being notwithstanding easy to close and to maintain in the closed position. | {
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1. Field of the Invention
The invention relates to a process for preparing a polymeric paste suitable for the preparation of dispersions and coatings.
2. Description of the Prior Art
Coatings prepared with selectively hydrogenated monoalkenyl arene/conjugated diene block copolymers have been proposed in the past. For example, U.S. Pat. No. 3,792,005 discloses the combination of a selectively hydrogenated block copolymer having specified block molecular weights and a particular solvent having a solubility parameter of 7.5 to 9.2 (cal/cm.sup.3).sup.1/2. The coatings of the '005 patent apparently have high tensile strength in combination with low solution viscosity. However, these coatings still must be applied to the substrate at relatively high solvent to polymer ratios. Today, such high solvent levels present environmental concerns, and special precautions must be undertaken to prevent pollution of the atmosphere.
A new process for applying coatings based on selectively hydrogenated monoalkenyl arene/conjugated diene block copolymer has been found. This new process permits the easy application of the coating to a substrate at very low solvent levels. | {
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Mode-locked ultra-short pulse fiber laser has many applications, such as micro machining, laser surgical operation, optical frequency measurement, etc. Nonlinear polarization rotation (NPR) has been used as an artificial saturable absorber in a fiber ring laser to start the mode-locking for many years. Traditionally, NPR mode-locked fiber ring laser requires the polarization of the laser to be elliptical at the input end of the fiber and nonlinear phase generated in the fiber makes the polarization ellipse rotate. To allow the polarization ellipse to rotate along the fiber, usually non-polarization-maintaining (non-PM) single mode fiber is used. The refraction index of non-PM single mode fiber can be changed by environmental temperature or pressure variation, thus, the polarization state of the laser light in the laser resonator can be changed and mode-locking may fail. Therefore, an environmental stable mode-locked fiber laser is urgent for reliably operating the ultra-short pulse fiber laser. | {
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1. Field of the Invention
The present invention relates to a system for generating a local clock signal synchronized to an external reference clock, and more particularly, to an improved digital system that provides precise control of the local clock, particularly for a SONET local clock generator.
2. Discussion of the Prior Art
A number of systems, for example, the Synchronous Optical Network (SONET) prescribed by ANSI T1.105-1988, "Digital Hierarchy Optical Interface Rates and Formats Specification", require a local clock generator that is precisely synchronized to an external reference clock source. For such applications, the system requires a local clock generator that continues to generate clock signals in the event of a loss of the reference clock source; a so-called clock hold-over mode of operation.
Various proposals have been made in the prior art for controlling a local reference clock source synchronized to an external reference clock. One commonly employed approach is to use a frequency responsive loop to establish initial synchronization between the local clock and the external clock, and to use a phase-locked loop to maintain precise synchronization once initial synchronization has been established. While generally satisfactory, these prior art controllers are relatively complex in their implementation and many do not provide for stable clock operation in the absence of the external reference clock. Further, in synchronizing the local clock to the external clock reference, prior art control systems may generate an excessive jitter in the local clock output, either in response to a jitter in the reference clock, or in establishing synchronization after a lost clock reference. As will be appreciated by those skilled in the art, jitter refers to a displacement in time of a significant instant (e.g., a rising edge) in the actual clock signal from its ideal position in time. | {
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The disclosure relates to the operation of a power conversion device and a control circuit at the time of operation stop.
The technology described in Japanese Unexamined Patent Application Publication No. 6-38361 is known as a power conversion device in related art.
The DC/DC converter as a power conversion device described in Japanese Unexamined Patent Application Publication No. 6-38361 is controlled by a microcomputer. A DC voltage is supplied from a commercial AC input to a power source which drives the microcomputer through a transformer, a rectifying smoothing unit, a switch, and a regulator. In order to reduce loss of the regulator, the transformer decreases the voltage of the commercial AC input. The switch is used to stop the operation of the microcomputer. When the output of the DC/DC converter is in an abnormal state, the microcomputer outputs a shutdown signal to the DC/DC converter and the switch to stop the operation of the DC/DC converter and the regulator. The microcomputer performs stop processing by the time when the output of the regulator starts to be stepped down.
However, in a DC/DC converter in related art, the microcomputer has to perform stop processing such as data saving by the time when the output of the regulator starts to be reduced. For this reason, if the time taken for the output of the regulator to start to be reduced is short, the data saving or the like may not be completed. If the data saving is not performed normally, the stop processing of the microcomputer may not be safely performed. To cope with this, the time taken for the output of the regulator to start to be reduced has to be increased, and thus the operation of the DC/DC converter cannot be quickly stopped.
Also, the above-mentioned transformer is a commercial AC transformer, and thus has a large size. In order to reduce the loss of the regulator without using the transformer, when the output voltage of the DC/DC converter is low, connecting the input of the regulator to the output voltage of the DC/DC converter reduces the loss. However, when the output of the DC/DC converter is lowered due to an operation of protection against overheat of the DC/DC converter, the power source of the microcomputer is reduced in power, and the microcomputer may not be able to safely perform the stop processing such as data saving. The DC/DC converter needs a function similar to the function of the regulator which supplies a power source to the microcomputer, and this leads to increase in chip size. | {
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In the manufacture of Large Scale Integrated (LSI) semiconductor chips on wafers, the ever-increasing miniaturization of the structures on the semiconductor chip are responsible in particular for imposing ever greater requirements on the production installations and manufacturing processes used for the manufacture of the semiconductor chips. The stability and reproducibility both of the production installations and of the manufacturing processes decisively influence the yield and productivity during semiconductor chip production. Even small deviations from a set-behavior of a wafer production installation during production can lead to considerable worsening of the yield, that is to say to a considerable increase in the defect rate of the semiconductor chips manufactured.
Consequently, a major aspect in the manufacture of semiconductor chips is to detect possible deviations from a set-behavior in a chip production installation or during a manufacturing process at a very early time and to take corresponding countermeasures. Consequently, the analysis and monitoring of machines, in particular of the chip production installations, and of the manufacturing processes takes on very great commercial significance. Furthermore, the analysis and monitoring of many process steps of the manufacturing process is of considerable significance, since it is usually only rarely possible to repair an intermediate product after a process step has been carried out. A functional test of a manufactured semiconductor chip is generally not scheduled until right at the end of the manufacturing process, which leads to very late feedback into the manufacturing process of the results obtained.
It is further known to provide in-line measurements of interim process results, for example of the layer thicknesses, the layer resistance or of line widths, etc., by means of Statistical Process Control (SPC). However, this leads to additional measuring steps in the overall manufacturing process and is consequently time-consuming and costly.
In Advanced Process Control (APC), data from internal and external sensors of the production installations are analysed in combination with measuring techniques used, including in-line measured data on intermediate products, as well as results of measurements on test structures, once the wafer has been completely processed, results of functional tests on the semiconductor chips, the yield of defect-free semiconductor chips, etc. In this way, both the stability of the production installations and the process stability can be increased significantly, and in this way so the production productivity and the product quality of the semiconductor chips manufactured can be increased.
In general, the semiconductor chips are manufactured several at a time on so-called wafers. These wafers are in turn grouped into so-called lots, in which a multiplicity of individual wafers are logistically combined for further treatment of the wafers and subjected together to semiconductor process steps.
For in-line measurements of intermediate process results as part of SPC, selections of random samples of wafers of a lot are performed. Test measurements, which relate either to the quality of the manufacturing steps of a manufacturing process or to the quality of the products manufactured, are then carried out on the selected samples of wafers.
According to the prior art, the sample selection generally takes place by means of so-called hands-on rules, i.e. an explicit, precise individual rule is prescribed and used as a basis for carrying out the sample selection. This may take place either by means of handling instructions, i.e. instructions as to how for example entire product groups are to be handled, or by means of explicit stop instructions in the process schedule, which concern selected lots of wafers. The sample selection is carried out separately after individual process steps.
U.S. Pat. No. 6,477,432 discloses a system for administering the quality control in a production installation for processing lots of products in processing for at least one product, which system has a manufacturing process and a Statistical Process Control (SPC) analyser.
U.S. Pat. No. 6,148,239 discloses a process control system which uses feedforward control threads which are based on material groups and which uses material tracking to take into account the variability of the processing in a process sequence. | {
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A variety of physical conditions involve two tissue surfaces that, for diagnosis or treatment of the condition, need to be separated or distracted or maintained in a separated condition from one another and then supported in a spaced-apart relationship. Such separation or distraction may be to gain exposure to selected tissue structures, to apply a therapeutic pressure to selected tissues, to return or reposition tissue structures to a more normal or original anatomic position and form, to deliver a drug or growth factor, to alter, influence or deter further growth of select tissues or to carry out other diagnostic or therapeutic procedures. Depending on the condition being treated, the tissue surfaces may be opposed or contiguous and may be bone, skin, soft tissue, or a combination thereof.
One location of the body where tissue separation is useful as a corrective treatment is in the spinal column. Developmental irregularities, trauma, tumors, stress and degenerative wear can cause defects in the spinal column for which surgical intervention is necessary. Some of the more common defects of the spinal column include vertebral compression fractures, degeneration or disruption of an intervertebral disc and intervertebral disc herniation. These and other pathologies of the spine are often treated with implants that can restore vertebral column height, immobilize or fuse adjacent vertebral bones, or function to provide flexibility and restore natural movement of the spinal column. Accordingly, different defects in the spinal column require different types of treatment, and the location and anatomy of the spine that requires corrective surgical procedures determines whether an immobilizing implantable device or a flexible implantable device is used for such treatment.
In a typical spinal corrective procedure involving distraction of tissue layers, damaged spinal tissue is removed or relocated prior to distraction. After the damaged tissue has been removed or relocated, adjacent spinal tissue layers, such as adjacent bone structures, are then distracted to separate and restore the proper distance between the adjacent tissue layers. Once the tissue layers have been separated by the proper distance, an immobilizing or flexible device, depending on the desired treatment, is implanted between the tissue layers. In the past, the implantable treatment devices have been relatively large cage-like devices that require invasive surgical techniques which require relative large incisions into the human spine. Such invasive surgical techniques often disrupt and disturb tissue surrounding the surgical site to the detriment of the patient.
Therefore, there remains a need for implantable treatment devices and methods that utilize minimally invasive procedures.
Such methods and devices may be particularly needed in the area of intervertebral or disc treatment. The intervertebral disc is divided into two distinct regions: the nucleus pulposus and the annulus fibrosus. The nucleus lies at the center of the disc and is surrounded and contained by the annulus. The annulus contains collagen fibers that form concentric lamellae that surround the nucleus and insert into the endplates of the adjacent vertebral bodies to form a reinforced structure. Cartilaginous endplates are located at the interface between the disc and the adjacent vertebral bodies.
The intervertebral disc is the largest avascular structure in the body. The cells of the disc receive nutrients and expel waste by diffusion through the adjacent vascularized endplates. The hygroscopic nature of the proteoglycan matrix secreted by cells of the nucleus operates to generate high intra-nuclear pressure. As the water content in the disc increases, the intra-nuclear pressure increases and the nucleus swells to increase the height of the disc. This swelling places the fibers of the annulus in tension. A normal disc has a height of about 10-15 mm.
There are many causes of disruption or degeneration of the intervertebral disc that can be generally categorized as mechanical, genetic and biochemical. Mechanical damage includes herniation in which a portion of the nucleus pulposus projects through a fissure or tear in the annulus fibrosus. Genetic and biochemical causes can result in changes in the extracellular matrix pattern of the disc and a decrease in biosynthesis of extracellular matrix components by the cells of the disc. Degeneration is a progressive process that usually begins with a decrease in the ability of the extracellular matrix in the central nucleus pulposus to bind water due to reduced proteoglycan content. With a loss of water content, the nucleus becomes desiccated resulting in a decrease in internal disc hydraulic pressure, and ultimately to a loss of disc height. This loss of disc height can cause the annulus to buckle with non-tensile loading and the annular lamellae to delaminate, resulting in annular fissures. Herniation may then occur as rupture leads to protrusion of the nucleus.
Proper disc height is necessary to ensure proper functionality of the intervertebral disc and spinal column. The disc serves several functions, although its primary function is to facilitate mobility of the spine. In addition, the disc provides for load bearing, load transfer and shock absorption between vertebral levels. The weight of the person generates a compressive load on the discs, but this load is not uniform during typical bending movements. During forward flexion, the posterior annular fibers are stretched while the anterior fibers are compressed. In addition, a translocation of the nucleus occurs as the center of gravity of the nucleus shifts away from the center and towards the extended side.
Changes in disc height can have both local and global effects. On the local (or cellular, level) decreased disc height results in increased pressure in the nucleus, which can lead to a decrease in cell matrix synthesis and an increase in cell necrosis and apoptosis. In addition, increases in intra-discal pressure create an unfavorable environment for fluid transfer into the disc, which can cause a further decrease in disc height.
Decreased disc height also results in significant changes in the global mechanical stability of the spine. With decreasing height of the disc, the facet joints bear increasing loads and may undergo hypertrophy and degeneration, and may even act as a source of pain over time. Decreased stiffness of the spinal column and increased range of motion resulting from loss of disc height can lead to further instability of the spine, as well as back pain.
Radicular pain may result from a decrease in foraminal volume caused by decreased disc height. Specifically, as disc height decreases, the volume of the foraminal canal, through which the spinal nerve roots pass, decreases. This decrease may lead to spinal nerve impingement, with associated radiating pain and dysfunction
Finally, adjacent segment loading increases as the disc height decreases at a given level. The discs that must bear additional loading are now susceptible to accelerated degeneration and compromise, which may eventually propagate along the destabilized spinal column.
In spite of all of these detriments that accompany decreases in disc height, where the change in disc height is gradual many of the ill effects may be “tolerable” to the spine and patient and may allow time for the spinal system to adapt to the gradual changes. However, the sudden decrease in disc volume caused by the surgical removal of the disc or disc nucleus may increase the local and global problems noted above.
Many disc defects are treated through a surgical procedure, such as a discectomy in which the nucleus pulposus material is removed. During a total discectomy, a substantial amount (and usually all) of the volume of the nucleus pulposus is removed and immediate loss of disc height and volume can result. Even with a partial discectomy, loss of disc height can ensue. Discectomy alone is the most common spinal surgical treatment, frequently used to treat radicular pain resulting from nerve impingement by disc bulge or disc fragments contacting the spinal neural structures.
The discectomy may be followed by an implant procedure in which a prosthesis is introduced into the cavity left in the disc space when the nucleus material is removed. Thus far, the most common prosthesis is a mechanical device or a “cage” that is sized to restore the proper disc height and is configured for fixation between adjacent vertebrae. These mechanical solutions take on a variety of forms, including solid kidney-shaped implants, hollow blocks filled with bone growth material, push-in implants and threaded cylindrical cages.
A challenge in the use of a posterior procedure to install spinal prosthesis devices is that a device large enough to contact the end plates and expand the space between the end plates of the same or adjacent vertebra must be inserted through a limited space. In the case of procedures to increasing intervertebral spacing, the difficulties are further increased by the presence of posterior osteophytes, which may cause “fish mouthing” or concavity of the posterior end plates and result in very limited access to the disc. A further challenge in degenerative disc spaces is the tendency of the disc space to assume a lenticular shape, which requires a relatively larger implant than often is easily introduced without causing trauma to the nerve roots. The size of rigid devices that may safely be introduced into the disc space is thereby limited.
While cages of the prior art have been generally successful in promoting fusion and approximating proper disc height, typically these cages have been inserted from the posterior approach, and are therefore limited in size by the interval between the nerve roots. Further, it is generally difficult, if not impossible to implant from the posterior approach a cage that accounts for the natural lordotic curve of the lumber spine.
It is desirable to reduce potential trauma to the nerve roots and yet still allow restoration or maintenance of disc space height in procedures involving vertebrae fusion devices and disc replacement, containment of the nucleus of the disc or prevention of herniation of the nucleus of the disc. In general minimally invasive surgical techniques reduce surgical trauma, blood loss and pain. However, despite the use of minimally invasive techniques, the implantation of cage devices for treating the spine typically involves nerve root retraction, an inherently high risk procedure. It is therefore desirable to reduce the degree of invasiveness of the surgical procedures required to implant the device, which may also serve to permit reduction in the pain, trauma, and blood loss as well as the avoidance and/or reduction of the nerve root retraction.
In minimally invasive procedures, to monitor placement, it is useful that implant devices inserted into spinal tissue be detectable using fluoroscopic imaging systems. However if a device is visible using X-ray technology, then the device can interfere with the detection and monitoring of spinal tissues, such as bone growing into the disc space after a vertebral fusion procedure. Additional advances would also be useful in this area. | {
"pile_set_name": "USPTO Backgrounds"
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Bacteriophages
Bacteriophages are bacterial viruses that attach to their specific hosts and kill them by internal replication and bacterial lysis involving a complex lytic cycle involving several structural and regulatory genes. Phages are very specific in that they only attack their targeted bacterial hosts. They cannot infect human or other eukaryotic cells. Bacteriophages were first identified, in the early part of the 20th century by Frederick Twort and Felix D'Herelle who called them bacteriophages or bacteria-eaters (from the Greek phago meaning to eat or devour). Duckworth (1976) Bacteriol Rev 40(4): 793-802; Summers (1999) Bacteriophage discovered. Felix d'Herelle and the origins of molecular biology. New Haven, Conn., Yale University Press: 47-59.
Lytic and Lysogenic Bacteriophages
Bacteriophages have a lytic cycle or a lysogenic cycle, but few bacteriophages are capable of carrying out both. With lytic phages such as the T4 phage, bacterial cells are broken open (lysed) and destroyed after immediate replication of the virion. As soon as the cell is destroyed, the new bacteriophage viruses can find new hosts. Kutter and Sulakvelidze (2005) Bacteriophages: Biology and Application. CRC Press: 381-436.
In contrast, the lysogenic cycle does not result in immediate lysing of the host cell. Those phages able to undergo lysogeny are known as temperate phages. Their viral genome will integrate with host DNA and replicate along with it fairly harmlessly, or may even become established as a plasmid. The virus remains dormant until host conditions deteriorate (e.g., due to depletion of nutrients) then the endogenous phages (known as prophages) become active. At this point they initiate the reproductive cycle resulting in lysis of the host cell. As the lysogenic cycle allows the host cell to continue to survive and reproduce, the virus is reproduced in all of the host cell's offspring. See Kutter and Sulakvelidze (2005) Bacteriophages: Biology and Application.
Bacteriophage Structure
Although different bacteriophages may contain different materials they all contain nucleic acid and protein. Depending upon the phage, the nucleic acid can be either DNA or RNA but not both, and it can exist in various forms. The nucleic acids of phages often contain unusual or modified bases. These modified bases protect phage nucleic acid from nucleases that break down host nucleic acids during phage infection. The size of the nucleic acid varies depending upon the phage. The simplest phages only have enough nucleic acid to code for 3-5 average size gene products while the more complex phages may code for over 100 gene products. The number of different kinds of protein and the amount of each kind of protein in the phage particle will vary depending upon the phage. The simplest phage have many copies of only one or two different proteins while more complex phages may have many different kinds. The proteins function in infection and to protect the nucleic acid from nucleases in the environment. See also McGrath and van Sinderen (2007)
Bacteriophage: Genetics and Molecular Biology.
Bacteriophage come in many different sizes and shapes. The basic structural features of bacteriophages include their size, head or capsid, tail. For example, T4, a common phage is among the largest phages; it is approximately 200 nm long and 80-100 nm wide. Other phages are smaller. Most phages range in size from 24-200 nm in length. All phages contain a head structure which can vary in size and shape. Some are icosahedral (20 sides) others are filamentous. The head or capsid is composed of many copies of one or more different proteins. Inside the head is found the nucleic acid. The head acts as the protective covering for the nucleic acid. Many but not all phages have tails attached to the phage head. The tail is a hollow tube through which the nucleic acid passes during infection. The size of the tail can vary, and some phages do not even have a tail structure. In the more complex phages like T4 the tail is surrounded by a contractile sheath which contracts during infection of the bacterium. At the end of the tail, the more complex phages like T4 have a base plate and one or more tail fibers attached to it. The base plate and tail fibers are involved in the binding of the phage to the bacterial cell. Not all phages have base plates and tail fibers. In these instances, other structures are involved in binding of the phage particle to the bacterium. See Kutter and Sulakvelidze (2005) Bacteriophages: Biology and Application.
Bacteriophage Infect Bacteria
The first step in the infection process is the adsorption of the phage to the bacterial cell. This step is mediated by the tail fibers or by some analogous structure on those phages that lack tail fibers, and it is reversible. The tail fibers attach to specific receptors on the bacterial cell, and the host specificity of the phage (i.e., the bacteria that it is able to infect) is usually determined by the type of tail fibers that a phage has. The nature of the bacterial receptor varies for different bacteria (e.g., proteins on the outer surface of the bacterium, LPS, pili, and lipoprotein). These receptors are on the bacteria for other purposes, and phage have evolved to use these receptors for infection. See Kutter and Sulakvelidze (2005) Bacteriophages: Biology and Application.
The attachment of the phage to the bacterium via the tail fibers is a weak one and is reversible. Irreversible binding of phage to a bacterium is mediated by one or more of the components of the base plate. Phages lacking base plates have other ways of becoming tightly bound to the bacterial cell.
The irreversible binding of the phage to the bacterium results in the contraction of the sheath (for those phages which have a sheath), and the hollow tail fiber is pushed through the bacterial envelope. Phages that do not have contractile sheaths use other mechanisms to get the phage particle through the bacterial envelope. Some phages have enzymes that digest various components of the bacterial envelope. See also McGrath and van Sinderen (2007) Bacteriophage: Genetics and Molecular Biology.
Lytic (Virulent) Phage Life Cycle
Lytic or virulent phages are phages which can only multiply on bacteria and kill the cell by lysis at the end of the life cycle.
During the eclipse phase, no infectious phage particles can be found either inside or outside the bacterial cell. The phage nucleic acid takes over the host biosynthetic machinery, and phage specified mRNAs and proteins are made. There is an orderly expression of phage directed macromolecular synthesis, just as one sees in animal virus infections. Early mRNAs code for early proteins which are needed for phage DNA synthesis and for shutting off host DNA, RNA and protein biosynthesis. After phage DNA is made, late mRNAs and late proteins are made. The late proteins are the structural proteins that comprise the phage as well as the proteins needed for lysis of the bacterial cell. See also McGrath and van Sinderen (2007) Bacteriophage: Genetics and Molecular Biology.
In the Intracellular Accumulation Phase, the nucleic acid and structural proteins that have been made are assembled and infectious phage particles accumulate within the cell.
During the Lysis and Release Phase, the bacteria begin to lyse due to the accumulation of the phage lysis protein, and intracellular phage are released into the medium. The number of particles released per infected bacteria may be as high as 1000.
A common assay for lytic phage is the plaque assay where lytic phage are enumerated by a plaque assay. A plaque is a clear area which results from the lysis of bacteria. Each plaque arises from a single infectious phage. The infectious particle that gives rise to a plaque is called a pfu (plaque forming unit). See Kutter and Sulakvelidze (2005) Bacteriophages: Biology and Application.
Lysogenic (Temperate) Phage Life Cycle
Lysogenic or temperate phages are those that can either multiply via the lytic cycle or enter a quiescent state in the cell. In this quiescent state most of the phage genes are not transcribed; the phage genome exists in a repressed state. The phage DNA in this repressed state is called a prophage because it is not a phage but it has the potential to produce phage. In most cases the phage DNA actually integrates into the host chromosome and is replicated along with the host chromosome and passed on to the daughter cells. The cell harboring a prophage is not adversely affected by the presence of the prophage, and the lysogenic state may persist indefinitely. The cell harboring a prophage is termed a lysogen. See also McGrath and van Sinderen (2007) Bacteriophage: Genetics and Molecular Biology, herein incorporated by reference in its entirety.
Anytime a lysogenic bacterium is exposed to adverse conditions, the lysogenic state can be terminated. This process is called induction. Adverse conditions which favor the termination of the lysogenic state include desiccation, exposure to UV or ionizing radiation, and exposure to mutagenic chemicals. This leads to the expression of the phage genes, reversal of the integration process, and lytic multiplication. See Kutter and Sulakvelidze (2005) Bacteriophages: Biolog and Application, herein incorporated by reference in its entirety.
At the time bacteriophages were discovered, with the age of antibiotics still in the future, bacteriophages were considered to be a potentially powerful cure for bacterial infections, and they were therapeutically utilized throughout the world during the pre-antibiotic era. The use of phages in humans was found to be very safe; however, phage therapy did not always work and, with the advent of antibiotics that were effective against a broad spectrum of pathogenic bacteria, it gradually fell out of favor in the United States and Western Europe. Several factors, including the lack of a broad understanding of phage biology, the “Soviet Taint,” and inadequate diagnostic bacteriology techniques, contributed to the failure of some of the early phage therapy studies and to the associated decline of interest in phage therapy in the West. Reviewed in more detail in Sulakvelidze, et al. (2001) Antimicrob Agents Chemother 45(3): 649-659 and Summers (2001) Ann Rev Microbiol 55: 437-51. At the same time, phage therapy continued to be utilized in the former Soviet Union and Eastern Europe, where phage therapy still is being used to treat a wide range of bacterial diseases ranging from intestinal infections to septicemia. Comprehensive information about human and veterinary applications of bacteriophages has been recently reviewed by several investigators. See, e.g., Alisky, et al. (1998) J Infect 36(1): 5-15; Summers (2001) Annu Rev Microbiol 55: 437-51; Merril, et al. (2003) Nat Rev Drug Discov 2(6): 489-497; Sulakvelidze & Barrow (2005) “Phage therapy in animals and agribusiness. Bacteriophages: Biology and Applications.” CRC Press: 335-380; Sulakvelidze & Kutter (2005). Bacteriophage therapy in humans. Bacteriophages: Biology and Application. CRC Press: 381-436.
Despite the use of bacteriophage in various practical settings, including the treatment of diseases in various animals, there remains in the art a need for the discovery of novel bacteriophages, selection of optimal bacteriophages for specific practical applications, and identifying methods for using these bacteriophages in several critical areas, including clinical applications, food safety-related uses and environmental decontamination. For example, one significant need concerns the treatment of processed or unprocessed food products to reduce, eliminate or prevent colonization with undesirable bacteria such as pathogens responsible for food-borne illness and food spoilage organisms. A second critical area of need concerns the removal of undesirable bacteria from industrial environments such as food processing facilities to prevent colonization thereof. A third critical area of need concerns the removal of antibiotic resistant organisms from environments where they may be passed to susceptible humans and animals, such as hospitals, nursing homes, veterinary facilities, and other such environments. Additionally, new bacteriophage and methods of using the same are needed for the prevention or treatment of animal and human bacterial disease, particularly those diseases caused by antibiotic-resistant organisms. Finally, bacteriophage compositions may be used a probiotics (e.g., the bacteriophage lyse undesirable bacteria leaving desirable microflora intact). | {
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Single handle mixing valves have become commonplace in today's plumbing market. However, many compromises have been built into mixing valves such as the compromises between large flow rates and easy temperature control. Furthermore, mixing valves are often built without pressure balance valves. Previous mixing valves that have been designed with a built-in pressure balance mechanism are bulky and not adequately packaged in a compact housing. However, lack of a pressure balance valve can result in rapid change of water temperature when either the hot water supply or the cold water supply pressure drops. The pressure drop can occur if another faucet, dishwasher, or washing machine is turned on, or a toilet is flushed. When either the cold or hot water supply pressure changes, discomfort can result if a person is taking a shower.
Furthermore, previous pressure balance valves have been complicated mechanisms that cannot be easily repaired or have its parts replaced.
What is needed is an easily assembled cartridge type mixing valve assembly which pressure balances the hot and cold water supply and provides full adjustment of the volume and temperature in a compact mixing valve housing having easily adjusted volume and temperature controls which work in the same fashion whether the hot and cold water supplies are attached to the mixing valve body in a normal or reversed fashion.
What is needed is a mixing valve that has its valve mechanisms housed in a cartridge that can be easily replaced when necessary. | {
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The present invention relates to the reaction of hydrogen gas with body centered cubic phase alloys, and particularly to the rapid reaction at mild temperatures of hydrogen gas with solid solution alloys having a body centered cubic phase structure.
Most metals that form hydrides react very slowly in bulk form at room temperature with hydrogen gas. Metallic niobium and metallic vanadium, for example, are relatively inert in bulk form at room temperature in the presence of hydrogen gas, with the hydrogen only slowly reacting with the body centered phase structure of each metal to form a precipitated niobium hydride or vanadium hydride. In the case of niobium, for example, attempts to increase the rate of reaction by plating the niobium with nickel or palladium or iron have been reported.
Metallic titanium is also relatively inert in the bulk form at room temperature in the presence of hydrogen gas. With titanium, the hydrogen only slowly reacts with the hexagonal close packed phase structure of titanium to form a precipitated titanium hydride.
In addition to the metals which form hydrides, a variety of alloys and intermetallic compounds which react with hydrogen are known in the art. U.S. Pat. No. 4,075,312 (Tanaka et al.) discloses titanium alloy hydride compositions containing at least one metal selected from the group consisting of vanadium, chromium, manganese, molybdenum, iron, cobalt, and nickel. J. J. Reilly et al., Inorganic Chemistry, 1974, Vol. 13, page 218, disclose intermetallic compounds of iron and titanium, FeTi and Fe.sub.2 Ti, which form iron titanium hydrides. J. F. Lynch et al., Advances in Chemistry, 1978, Vol. 167, pp. 342-365, disclose titanium-molybdenum alloys useful for hydrogen isotope separation. U.S. Pat. No. 4,228,145 (Gamo et al.) discloses a Laves phase intermetallic compound, TiMn2, which forms hydrides.
For many applications of metal hydrides, such as hydrogen storage, it is desirable to form the hydride from bulk metal or alloy, pulverize the hydride into some of granular or powdered structure, and thereafter cyclically remove hydrogen to form a lower hydride or the free metal or alloy, and thereafter reintroduce hydrogen to form the hydride. Starting with the bulk metals or bulk alloys described heretofor, it is necessary to go through an induction period, wherein the metal is heated to a high temperature such as 300.degree. C.-700.degree. C., then reacted with hydrogen at high pressure and then cooled very slowly until a temperature below about 100.degree. C. is reached (preferably about room temperature). At the high temperature, the rate of hydrogen dissolving in the metal is increased so as to achieve saturation in a matter of minutes rather than hours or days. At the high temperature, however, the equilibrium hydrogen pressure is so high that relatively little hydrogen actually dissolves to form hydrides. Accordingly, it is only upon a gradual cooling that sufficient hydride is formed. While many metals require only a single induction process to form the hydride, with the subsequent hydride powder cycling at a reasonable reaction rate, it should be apparent that the induction process represents a distinct disadvantage in forming and utilizing metal hydrides.
Recently, it has been discovered that certain body centered cubic solid solution alloys react rapidly with hydrogen at mild temperatures. More particularly, U.S. Pat. Nos. 4,425,318 (Maeland et al.) and 4,440,737 (Libowitz et al.) disclose body centered cubic solid solution alloys of niobium, vanadium, and tantalum (among others) which react rapidly with hydrogen under mild conditions. In addition, U.S. Pat. No. 4,440,736 (Maeland et al.) discloses titanium based alloys which react rapidly with hydrogen under mild conditions in which the body centered cubic structure has been stabilized by the addition of a body centered cubic metal such as vanadium, niobium or molybdenum. | {
"pile_set_name": "USPTO Backgrounds"
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This invention relates to spread-spectrum communications, and more particularly to a method employed by a remote terminal for reducing interference in a direct sequence, code division multiple access receiver. | {
"pile_set_name": "USPTO Backgrounds"
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a) Field of the Invention
The present invention relates to an illumination device, and more specifically to an illumination device so adapted as to permit obtaining a surface light source having uniform luminance.
b) Description of the prior art
The conventional illumination devices comprise linear light source(s) 2 consisting of a single or plural fluorescent tubes, etc. arranged over a flat or curved reflecting plate 1 as shown in FIG. 1, and a diffusing plate 3 arranged on the side opposite to the linear light source 2.
Out of these illumination devices, the illumination device using a single linear light source provides such luminance distribution on the diffusing plate as shown in FIG. 2 on which luminance is the highest at the central area close to the light source 1 and luminance is gradually lowered toward the marginal portion, thereby making luminance non-uniform over the entire range of the diffusing plate 3. Especially when the light source 2 is brought closer to the diffusing plate 3 to design a this illumination device, luminance is especially enhanced at the area right over the light source 2, out of the areas of the diffusing plate 3, by the rays emitted upward from the light source 2 and attaining directly to the diffusing plate 3. For this reason, attempts have previously been made to obtain uniform luminance distribution on the diffusing plate by reducing the rays emitted upward from the light source.
As a conventional example accomplished by such an attempt, there is known the illumination device disclosed by Japanese Published Unexamined Utility Model Application No. 90106/61. In this example as shown in FIG. 3, a plural number of linear light-shielding portions 4 having a definite width are arranged discontinuously on the top (close to the diffusing plate) of a fluorescent tube used as the linear light source. In this conventional example, the rays emitted upward from the light source are partially shielded by the light shielding portions and the rays to attain to the central area of the diffusing plate located right over the linear light source are reduced, thereby lowering luminance at the central area. However, luminance is still high at the outer areas neighboring the central area and luminance distribution is as shown in FIG. 4, whereby luminance distribution is not so uniform on the diffusing plate.
As another example of the illumination devices of this type, there is also known the illumination device disclosed by Japanese Published Unexamined Patent Application No. 133008/55. In this illumination device, arranged between the diffusing plate and the light source is a light quantity adjusting plate 6 on which light-shielding portions 5 such as black spots are distributed at an adequate density as shown in FIG. 5 for the purpose of obtaining relatively uniform luminance distribution by reducing the rays to reach the area at which luminance would be otherwise high.
This conventional illumination device can provide rather uniform luminance distribution on the diffusing plate, but requires delicate adjustment of the space between the light source and the light quantity adjusting plate at the assembly stage of the illumination device and therefore poses a relatively difficult problem to maintain high precision for the space. Further, when the illumination device comprises a plural number of light sources, distribution, density, etc. of the light-shielding portions must be varied on the light quantity adjusting plate in accordance with variation of luminance on the tube surfaces of the light source, thereby posing a difficult adjusting problem. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The present invention relates to a trace display apparatus for a navigation system which is mounted on a mobile body.
2. Description of the Related Art
Generally, a conventional navigation system mounted on an automobile employs a positioning system in which the dead reckoning, the map-matching, and the global positioning system (hereafter, abbreviated as "GPS") are used in combination. In the dead reckoning, the traveling locus of the automobile is obtained by means of an azimuth sensor and a distance sensor which are mounted on the automobile, and a relative position of the automobile is calculated. A prior art of navigation system using the dead reckoning is disclosed, for example, in Japanese Unexamined Utility model Publication (Kokai) No. JP-U 57-32,980 (1982). In the map-matching, the position of the automobile on a map results from comparing the traveling locus of the automobile obtained by the dead reckoning with road arrangement appearing on the map, so as to determine the road on which the automobile has passed. Since the map-matching determines a relative position of the automobile, errors may be accumulated in the position data. However, when the position data are combined with the information about the absolute position of the automobile which is obtained from the GPS, the resulting position data have a higher accuracy.
The GPS is a novel positioning system which has been developed by the National Military Establishment of the U.S. and uses a plurality of artificial satellites. The artificial satellites are orbiting around the earth and always transmitting signals indicative of orbit data, the time or the like. At a measuring point, signals transmitted from four satellites among these artificial satellites are received, and the time periods required for arrival of the signals are obtained. The distance between each artificial satellite and the measuring point is calculated from these time periods, so that it is possible to obtain the three-dimensional position (latitude, longitude and altitude) of the measuring point. When the two-dimensional position (latitude and longitude) of the measuring point is to be obtained, signals from three artificial satellites are received to calculate. In the shade of buildings in an urban area or in a tunnel, however, it is impossible to receive signals from the artificial satellites. In such a case, the position of an automobile is obtained by the dead reckoning. Japanese Unexamined Patent Publication (Kokai) No. JP-A 2-243,984 (1990) discloses a prior art system in which, using artificial satellites, the position (latitude and longitude) of a measuring apparatus on the earth is obtained in a manner different from that of the GPS.
When the position of an automobile is measured in a navigation system, a map including the automobile position is displayed on screen of a display apparatus. The information of the map is previously stored in a read-only memory using a compact disk for the navigation system (hereafter, such a memory is abbreviated as "CD-ROM"). When necessary information is read out from the CD-ROM, a mark indicating the automobile position is then superimposed on the displayed map. When the automobile position almost reaches one end of the map, the display is automatically changed to the adjacent map. Furthermore, such system can receive transportation information from a road beacon to display it on the screen. The system can receive also position information to correct the obtained current position.
FIG. 6 shows an example of the display of moving traces 1 of an automobile as a traveling locus on a display apparatus by a typical prior art navigation system. The automobile departs from the starting point 2. The two-dimensional position (latitude and longitude) of the automobile is obtained by a position measurement using the GPS or the like, and the positions are recorded until the automobile arrives the end point 3. In the figure, the thin solid lines indicate roads on the map, and the thick solid lines indicate the moving traces 1 of the automobile.
FIG. 7 shows an example of the display to indicate moving traces 5 and an altitude for an automobile on a display apparatus according to another prior art navigation system. In FIG. 6, the moving traces 1 of the automobile are only two-dimensionally displayed. In FIG. 7, when the user designates a point 6 on the screen, the altitude value 7 corresponding to the point 6 is displayed in the right and lower portion of the screen. Prior art navigation systems using the GPS are disclosed, for example, in Japanese Unexamined Patent Publications (Kokai) No. JP-A 63-26,529 (1988) and JP-A 3-17,688 (1991).
A trace display apparatus for a navigation system according to any prior art, the altitude of a mobile body is not displayed as shown in FIG. 6, or the altitude value of an arbitrary point designated by the user is displayed on a screen. Therefore, it is not easy to grasp the altitude change in the traces of a mobile body from a starting point to an end point. | {
"pile_set_name": "USPTO Backgrounds"
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