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Field
The disclosed embodiments relate to power management in computer systems. More specifically, the disclosed embodiments relate to techniques for reducing power consumption by overriding latency tolerance reporting (LTR) values in components of computer systems.
Related Art
A modern computer system typically includes a motherboard containing a processor and memory, along with a set of peripheral components connected to the motherboard via a variety of interfaces. For example, a Serial Advanced Technology Attachment (SATA) interface may facilitate data transfer between a storage device (e.g., hard disk drive, optical drive, solid-state drive, hybrid hard drive, etc.) and the motherboard, while a Peripheral Component Interconnect Express (PCIe) bus may enable communication between the motherboard and a number of integrated and/or add-on peripheral components.
In addition, use of the interfaces by the peripheral components may affect the power consumption of the computer system. For example, a Central Processing Unit (CPU) of the computer system may not be able to enter a low-power state while the CPU is executing and/or a PCIe interface is used by a peripheral component in the computer system. The CPU may further be kept from entering and/or staying in the low-power state if the peripheral component does not have the capability to provide a Latency Tolerance Reporting (LTR) value to the CPU and/or root complex of the PCIe interface. As a result, the CPU may be required to stay in a higher-power state to satisfy a default and/or minimum latency tolerance for the peripheral component, even if the peripheral component can tolerate a higher latency from the CPU.
Consequently, power consumption in computer systems may be improved by assessing latency tolerances of peripheral components in the computer systems and operating processors in the computer systems based on the assessed latency tolerances. | {
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The present disclosure relates generally to techniques that determine object characteristics using light emanating from the objects. More specifically, the techniques can use filter arrangements to allow for the transmission, reflection, fluorescence, phosphorescence, photoluminescence, chemoluminescence and/or scattering of light with time variation, such as where the objects are moving relative to the filter arrangements.
Various techniques have been proposed for using light emanating from objects. For example, U.S. Pat. No. 7,358,476 (Kiesel et al.) describes a fluidic structure with a channel along which is a series of sensing components to obtain information about objects traveling within the channel, such as droplets, cells, viruses, microorganisms, microparticles, nanoparticles, or other objects carried by fluid. A sensing component includes a set of cells that photosense a range of photon energies that emanate from objects. A processor can receive information about objects from the sensing components and use it to obtain spectral information. Additional techniques are described, for example, in U.S. Patent Application Publications 2008/0181827 (Bassler et al.) and 2008/0183418 (Bassler et al.) and in U.S. Pat. No. 7,701,580 (Bassler et al.), U.S. Pat. No. 7,894,068 (Bassler et al.), U.S. Pat. No. 7,547,904 (Schmidt et al.), U.S. Pat. No. 8,373,860 (Kiesel et al.), U.S. Pat. No. 7,420,677 (Schmidt et al.), and U.S. Pat. No. 7,386,199 (Schmidt et al.). | {
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The invention relates generally to systems for managing patient care in a health care facility, and more particularly, to systems for collecting data and controlling the delivery of patient care.
Medical institutions are faced with a competitive environment in which they must constantly maintain or improve profitability and yet simultaneously improve patient care. Several factors contribute to the ever increasing costs of health care, whether it is delivered to the patient in a hospital or out-patient clinic setting. Health care deliverers face increased complexity in the types of treatment and services available, but also must provide these complex treatments and services efficiently, placing a premium on the institution's ability to provide complex treatment while maintaining complete and detailed medical records for each patient.
It is also advantageous to have a care management system that combines all of the various services and units of a health care institution into an interrelated automated system to provide “just-in-time” delivery of therapeutic and other drugs to the patient. Such a system would prevent administering an inappropriate medication to a patient by checking the medication against a database of known allergic reactions and/or side-effects of the drug against the patent's medical history. The interrelated system should also provide doctors, nurses and other care-givers with updated patient information at the bedside, notify the institution's pharmacy when an additional drug is required, or when a scheduled treatment is running behind schedule, and automatically update the institution's accounting database each time a medication or other care is given.
Inaccurate recording of the administration of drugs and usage of supplies involved in a patient's treatment results in decreasing revenues to the institution by failing to fully capture billing opportunities of these actual costs. Inadequate management also results in a failure to provide an accurate report of all costs involved in treating a particular illness.
In many hospitals and clinical laboratories, a bracelet device having a patient's name printed thereon is permanently affixed to a patient upon admittance to the institution in order to identify the patient during his or her entire stay. Despite this safeguard, opportunities arise for patient identification error. For example, when a blood sample is taken from a patient, the blood sample must be identified by manually transcribing the patient's name and other information from the patient's identification bracelet. In transferring the patient's name, a nurse or technician may miscopy the name or may rely on memory or a different data source, rather than actually reading the patient's bracelet.
Moreover, manually transferring other information, such as the parameters for configuring an infusion pump to dispense medication may result in errors that reduce the accuracy and/or effectiveness of drug administration and patient care. This may result in an increased duration of treatment with an attendant increase in costs.
Hospitals and other institutions must continuously strive to provide quality patient care. Medical errors, such as where the wrong patient receives the wrong drug at the wrong time, in the wrong dosage or even where the wrong surgery is performed, are a significant problem for all health care facilities. Many prescription drugs and injections are identified merely by slips of paper on which the patient's name and identification number have been handwritten by a nurse or technician who is to administer the treatment. For a variety of reasons, such as the transfer of patients to different beds and errors in marking the slips of paper, the possibility arises that a patient may be given an incorrect treatment. This results in increased expense for the patient and hospital that could be prevented using an automated system to verify that the patient is receiving the correct care.
Various solutions to these problems have been proposed, such as systems that use bar codes to identify patients and medications, or systems allowing the bedside entry of patient data. While these systems have advanced the art significantly, even more comprehensive systems could prove to be of greater value.
What has been needed, and heretofore unavailable, is an integrated, modular system for tracking and controlling patient care and for integrating the patient care information with other institutional databases to achieve a reliable, efficient, cost-effective delivery of health care to patients. The invention fulfills these needs and others. | {
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Games using a cellular phone terminal equipped with a GPS (Global Positioning System) have recently attracted attention. In the location game “Ichige” (registered trade name, No. 5302412 of COLOPL Inc.) of this kind, position information (latitude, longitude) is acquired for each predetermined time interval, the movement distance is calculated on the basis of a difference in position information between a large number of locations, and incentives such as points corresponding to the movement distance of the user that owns the cellular phone terminal are added.
Such location game “Ichige” (registered trade name, No. 5302412 of COLOPL Inc.) will apparently also generate a business of converting the points that have been acquired correspondingly to the movement distance into virtual currency for Internet purchases or mileage for transportation means. Therefore, it is necessary that the movement distance be calculated correctly.
A system for adding mileage points is disclosed in Japanese Patent Application Publication No. 2002-304563 (Patent Document 1).
Patent Document 1: Japanese Patent Application Publication No. 2002-304563
However, some users can perform fraudulent acts of intentionally extending the measured distance of the position information and acquiring a large travel distance by using poor reception (out-of-range) of the cellular phone terminal or by operating the movement distance by falsifying parameters assigned to the position information. Patent Document 1 does not address this issue. | {
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1. Field of the Invention
The present invention relates to an integrated circuit component constituted by mounting, on a wiring board having mounted thereon an integrated circuit module, a chip part which adjusts impedance of wiring patterns. The present invention also pertains to a method for mounting the chip part.
2. Description of the Related Art
As this type of integrated circuit component, there is conventionally known, for example, a component having a bypass capacitor as a chip part as shown in FIG. 15 or a component having a damping resistor as a chip part as shown in FIG. 16.
First, an integrated circuit component as shown in FIG. 15 is described. FIG. 15A is a sectional view of an integrated circuit component having a bypass capacitor, FIG. 15B is a sectional view taken along a line D-D of FIG. 15A, and FIG. 15C is a view in the direction of an arrow E of FIG. 15A.
As shown in these figures, an integrated circuit component 101 has a BGA (Ball Grid Array)-type LSI chip 110 (an integrated circuit module). An external terminal of the integrated circuit component 101 is formed by a plurality of solder bumps 111.
The LSI chip 110 is manufactured, for example, through a process as shown in FIG. 17. More specifically, the LSI chip 110 is manufactured by the following process. First, a BGA package substrate 113 having formed thereon land sections 112 constituting the external terminal is prepared (FIG. 17A). Further, flux 114 is coated on each of the land sections 112 (FIG. 17B). A solder ball 111′ with a predetermined size is placed on the flux 114 (FIG. 17C). Further, the solder ball 111′ is melted to allow the flux 114 to be volatilized. Thus, the LSI chip 110 having mounted thereon solder bumps 111 is obtained (FIG. 17D).
Turning now to FIG. 15, the integrated circuit component 101 is constituted by mounting a bypass capacitor 130 on a wiring board 120 having mounted thereon the LSI chip 110 by solder bonding. In order to prevent or suppress switching noise of the LSI chip 110, the bypass capacitor 130 is mounted near an outside of the LSI chip 110 in an LSI chip 110 mounting surface side of the wiring board 120, or is mounted on a wiring pattern 121 formed on an opposite surface side of the LSI chip 110 mounting surface. Further, the capacitor 130 adjusts inductance and impedance of the wiring pattern 121.
More specifically, accompanying fast switching of the LSI, power feed through the wiring patterns must also be performed at high speed. However, since response speed of the power itself cannot follow current fluctuation of the LSI and the response speed is delayed due to inductance components in a feeder line of the power, switching noise is generated. In order to prevent generation of the switching noise, the bypass capacitor 130 is placed near the LSI chip 110 as shown in the same figure to compensate for response delay of the power. Further, the inductance components of the wiring pattern 121 as a power supply line are reduced.
Next, an integrated circuit component as shown in FIG. 16 is described. FIG. 16A is a sectional view of an integrated circuit component having a damping resistor, FIG. 16B is a sectional view taken along a line F-F of FIG. 16A, and FIG. 16C is a view in the direction of an arrow G of FIG. 16A. In the figure, the same elements as those of FIG. 15 are indicated by the same reference numerals as in FIG. 15 and the description is omitted.
As shown in these figures, an integrated circuit component 102 is constituted by mounting a damping resistor 150 on a wiring board 140 having mounted thereon an LSI chip 110. In order to reduce switching noise or electromagnetic noise in transmission signals transmitted to and from the LSI chip 110, or to suppress reflection, overshoot or undershoot of transmission signals, the damping resistor 150 adjusts impedance of the wiring pattern 141 to realize the impedance matching.
A mounting position of the damping resistor 150 is preferably near an output terminal or input terminal (near a solder bump 111) of the transmission signals between the LSI chip 110 and the wiring board 140 in terms of performance of the impedance matching. Along with a recent tendency to increase capacity (speeding up) of the transmission signals, a rise time and fall time of the signal waveform is extremely reduced. As a result, the wiring pattern 141 which connects between the damping resistor 150 and the output terminal or the input terminal may be required to have a length of about several millimeters.
However, the length of the wiring pattern in the above-described constitution is as follows. As shown in each of FIGS. 15 and 16, each of the lengths L1 and L2 (including each length of vias 122 and 142 which connect between the wiring patterns) of the wiring patterns 121 and 141 equivalent to the sum of leaders of both electrodes in each chip part is about from 6 mm at the minimum to several dozen mm at the maximum. Each of the lengths L3 and L4 of the wiring patterns 121 and 141 in the connecting side with the LSI chip 110 is about 3 mm at the minimum. Practically, in the LSI chip 110, pins (solder bumps) as a connecting object with the chip part are scarcely positioned on the outermost periphery of the LSI chip 110 and are almost always positioned on the inner side of the LSI chip 110. Therefore, the real leader length of the wiring pattern from the LSI chip 110 is about 10 to 20 mm. Accordingly, each of the lengths L1 and L2 of the wiring patterns 121 and 141 equivalent to the sum of the leaders in both the electrodes becomes as long as about 10 to 25 mm. As a result, there is a problem that the above-described switching noise is easily generated due to the lengths of the wiring patterns 121 and 141.
To solve the above-described problem, there is proposed, for example, a capacitor mounting structure of mounting a bypass capacitor between a BGA-type integrated circuit device (an LSI chip) and a wiring board (see, e.g., Japanese Unexamined Patent Publication No. 2001-102512 (FIG. 1)).
FIG. 18A is a sectional view showing an outline of this capacitor mounting structure, and FIG. 18B is a sectional view taken along a line H-H of FIG. 18A. As shown in these figures, in a capacitor mounting structure 103, a bypass capacitor 173 is mounted so as to bridge predetermined adjacent solder pastes 172 among a plurality of solder bumps aligned on a mounting surface of an LSI chip 171. The LSI chip 171 is mounted on the wiring board 175 through other solder balls 174.
By thus mounting the bypass capacitor 173 between the LSI chip 171 and the wiring board 175, the bypass capacitor 173 is disposed near an integrated circuit, and as a result, the switching noise can be suppressed to some extent.
However, the technology described in Japanese Unexamined Patent Publication No. 2001-102512 (FIG. 1) has the following problems.
A first problem is as follows. That is, since a special process is required for the above-described mounting of the bypass capacitor 173 on the LSI chip 171 side, a manufacturing cost is increased. FIG. 19 shows an assumed manufacturing process of the LSI chip 171.
Specifically, the LSI chip 171 is manufactured by the following process. First, a BGA package substrate 183 having formed thereon land sections 182 constituting the external terminal is prepared (FIG. 19A). Further, in each of the land sections 182, special solder pastes 172′ are printed on a place where the bypass capacitor 173 is mounted and predetermined solder pastes 184 are printed on the other places (FIG. 19B). Further, the bypass capacitor 173 is placed on the solder pastes 172′ (FIG. 19C). Subsequently, a solder ball 174 is placed on the other solder pastes 184 (FIG. 19D). Further, these solder pastes are melted and reflowed. Thus, the LSI chip 171 having mounted thereon the bypass capacitor 173 and the solder balls 174 is obtained (FIG. 19E).
In the above-described manufacturing process, a necessary amount of solder paste is different between in a mounting place of the bypass capacitor 173 and in a mounting place of the solder ball 174. Therefore, a special stencil for printing is required. Further, no solder ball 174 is mounted on a mounting place of the bypass capacitor 173 irrespective of individual mounting or collective mounting. Therefore, a special tool is required. Thus, the manufacturing process has a technical/cost problem.
A second problem is as follows. That is, a scope of design is limited by designers and manufacturers.
More specifically, the designers and manufacturers which design an integrated circuit component containing a BGA-type integrated circuit module generally contracts out the integrated circuit module to a BGA mounting maker which specializes in BGA. Accordingly, a mounting position, number and characteristics of a bypass capacitor or a damping resistor must be previously determined at the time of order placement and therefore, are difficult to be changed later. Particularly in the damping resistor, a problem may occur in a characteristic assessment after the manufacture of the first lot due to shortage of characteristic investigation in designing of a wiring board or due to variation in characteristics of LSI. Therefore, a change of constants which specifies the characteristics may be required. However, in the case of mounting the damping resistor on the integrated circuit module side, coordination with the BGA mounting maker is necessary in changing the constants. As a result, any action may not be easily taken due to problems such as a period or cost.
A third problem is as follows. That is, when mounting the bypass capacitor between the LSI chip and the wiring board, the feeder line remains long. FIG. 20A is an enlarged sectional view showing an essential part of the capacitor mounting structure 103 which indicates this problem. FIG. 20B is a sectional view taken along a line I-I of FIG. 20A.
As shown in FIG. 20A, power transmitted through a power supply line 191 which constitutes wiring patterns of the wiring board 175 is transmitted to the bypass capacitor 173 through a via 192, a pad 193 and a solder paste 172. Further, the power reaches a ground line 196 through a solder paste 172, a pad 194 and a via 195. In short, the power is transmitted in a mode of once making a long detour toward the LSI chip 171 side. Therefore, the response speed of the power is delayed due to inductance components in the transmission path of the power, and as a result, an effect of reducing switching noise cannot be greatly obtained. | {
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The present invention relates to fibrous web finishing. In particular, the invention concerns a method according to the preamble of claim 1 for increasing the smoothness of paper and board webs by mechanical treatment.
Paper is normally manufactured by the wet method. According to that method fibres are suspended in water to form a fibrous furnish and a wet web is formed from the furnish on a wire screen. The web is then dried step by step using different mechanical and thermal systems to a preselected state of dryness.
In conventional technology, the fibrous furnish is maintained in turbulent state before web formation in order to avoid orientation of the fibres. However, as a result of the turbulence, there will be formed flocks in the web, having a fibre density larger than that of the surrounding parts of the web.
For the purpose of all printing operations, the surface of the paper should be as smooth and/or homogeneous as possible. The same is true for papers coated with mineral particle layer and latex binding materials. Therefore, very often (base) papers are calendered before coating and also papers containing mineral fillers are treated with a calender for achieving a smoother surface. Calendering is in particular necessary for certain paper qualities because of the above-mentioned flock formation.
There are numerous types of calenders, but all of them even the surface by mechanical pressing and sliding forces. Conventional calendering is hampered by some considerable disadvantages. After remoisturing, a surface smoothened by calendering will totally or partially regain its original form. It is also known that papers loose up to 35-40% of its strength properties and 25-35% of its original opacity as a result of calendering. Further, the original tenacity of the paper web will remarkably decrease.
In view of the above problems related to calendering, great efforts have been made to avoid said flock formation and to find some different methods for surface smoothening.
U.S. Pat No. 2,349,704 discloses a method for polishing the surface of a paper web with a cloth polishing roll. The surface of the roll contains a powdered abrasive which is bound to the surface with the aid of a binder. The object is to press and polish paper to the same extent as is made by the supercalendering process, and according to specification of the patent, the density of the treated paper is the same as after a supercalendering process and gloss, measured by a Baush and Lomb glossmeter, is 10 points higher than before the treatment.
U.S. Pat. No. 5,533,244 discloses another method, somewhat similar to the one mentioned above, for polishing paper with a woven belt which slides at different speed over the paper web than the web itself, producing frictional action.
A soft calender device which acts as a rubbing friction device on paper surface is disclosed in U.S. Pat. No. 4,089,738. The device will smoothen the paper surface in the same way as original supercalenders.
None of the prior art method will provide for a satisfying removal of high density flocks from the paper surface. Further, it is apparent that the strength properties of the paper deteriorate during the application of the known methods.
It is, therefore, an object of the present invention to eliminate the disadvantages of the prior art and to provide a novel method for treating the surface of a fibrous web, in particular a paper or board surface in order to improve its smoothness while substantially retaining the mechanical properties of the web.
The present invention is based on the surprising finding that the surface of many fibrous webs can be smoothen by grinding off only the most protruding parts of the web with a grinding means, such as a grinding belt or viberating grinding device or rotating grinding cylinder, to provide a smoothened surface having unaltered or even improved properties of mechanical strengthness. In particular, the presention comprises grinding in the dry state (xe2x80x9cdry grindingxe2x80x9d) only the higher parts of fibrous web (in cross section) while pressing the surface against the grinding surface so little that no noticeable increase of density of the web can be found.
More specifically, the invention is mainly characterized by what is stated in the characterizing part of claim 1.
The present invention provides a number of advantages. Surprisingly, it has been found that, e.g., ground paper had a better tensile strength and also better bursting strength that the original paper. Although we do not wish to be bound by any particular theory, it would appear that this phenomenon is based on the forces inside the stressed web becoming more evenly distributed when the strength of the parts having the highest strength is decreased. Initially, because of the poor evenness (formation) of the paper web, the forces are not so strong at the thinnest part of the paper. However, grinding will redistribute the adhesion forces within the web matrix. Another possible explanation is that fines generated obviously during the grinding process and also fibrils, one end of which still sticks to the original fibre, are reassembled on the surface.
During the surface grinding process of the present invention, very limited amounts of loose fibres and dust are formed. This is probably because the grinding friction of the present invention will release some water vapour from the surface and it will condense on the paper leaving the grinding process part of machinery. This condensed water will bind fines back to the surface.
Next the invention will be examined in more detail with the aid of the following detailed description and with reference to a working example.
Within the scope of the present invention, the terms xe2x80x9ccellulosicxe2x80x9d and xe2x80x9clignocellulosicxe2x80x9d are used to designate materials derived from cellulose and lignocellulosic materials, respectively. In particular xe2x80x9ccellulosicxe2x80x9d refers to material obtainable from chemical pulping of wood and other plant raw material. Thus, a web containing xe2x80x9ccellulosic fibresxe2x80x9d is made for example from kraft, sulphite or organosolv pulp. xe2x80x9cLignocellulosicxe2x80x9d refers to material obtainable from wood and other plant raw material by mechanical defibering, for example by an industrial refining process, such as refiner mechanical pulping (RMP), pressurized refiner mechanical pulping (PRMP), thermomechanical pulping (TMP), groundwood (GW) or pressurized groundwood (PGW), or chemithermo-mechanical pulping (CTMP) or any other method for manufacturing a fibrous material which can be formed into a web and coated.
The terms xe2x80x9cpaperxe2x80x9d and xe2x80x9cpaperboardxe2x80x9d refer to sheet-formed products containing cellulosic or lignocellulosic fibres. xe2x80x9cPaperboardxe2x80x9d is synonymous with xe2x80x9ccardboardxe2x80x9d. The grammage of the paper or paperboard can vary within broad ranges from about 30 to about 500 g/m2. The roughness of the web which is to be treated in about 0.1 to 30 xcexcm, preferably about 1 to 15 xcexcm. The present invention can be employed for treating any desired paper or paperboard web. As a practical matter, the term xe2x80x9cpaperxe2x80x9d or xe2x80x9cpaper webxe2x80x9d is herein used to designate both xe2x80x9cpaperxe2x80x9d and xe2x80x9cpaperboardxe2x80x9d and xe2x80x9cpaper webxe2x80x9d and xe2x80x9cpaperboard webxe2x80x9d, respectively.
The terms xe2x80x9cfinesxe2x80x9d, xe2x80x9cfibrilsxe2x80x9d and xe2x80x9cfibresxe2x80x9d denote finely divided material having a cross-sectional diameter of less than about 10 xcexcm, typically in the range of 0.001 to 2 xcexcm and the xe2x80x9cfibrilsxe2x80x9d and xe2x80x9cfibresxe2x80x9d are materials having a length to cross-section diameter ratio of more than about 6.
The xe2x80x9croughnessxe2x80x9d of the web which is to be coated is generally given as xe2x80x9cmicronsxe2x80x9d (xcexcm). The print-surf surface roughness at 1000 kPa can be measured according to, for example, ISO 8791-4:1992 (E). Typically the roughness of paper webs is in the range of 8 to 2 microns. As discussed below and shown in the working examples, by subjecting the surface of a paper or paperboard web to a grinding treatment according to the invention, it is possible to reduce the roughness of the web by at least 20%, preferably about 40 to 60% while maintaining the mechanical properties of the web.
The present invention comprises the steps of forming a wet web from a fibrous furnish on a wire screen. The web is then dried on a paper or board machine to preselected state of dryness. At any desired point of the drying, but preferably after the web has been dried to sufficient dryness to impair reasonable mechanical strength on the web, the web is subjected to a dry grinding operation as explained in more detail below. The grinding can be carried out between the unwinding and winding of the web. After the grinding and possible smoothing, the treated web can then be coated with suitable coating colours as known per se.
The grinding according to the invention is carried out by contacting the surface of the paper web with a grinding means. According to a preferred embodiment of the present grinding process, the grinding is made by grinding grains fixed to a movable grinding belt or a vibrating plate which produces a not glossy but faded or mat surface. The preferable size of the grinding media grains is between about 5-20 micron, of course depending on the surface quality and the surface weight of the paper or board. The surface of the grinding medium is essentially dry (moisture content less than about 50%, preferably less than 20% and in particular less than 10%) and preferably no water is fed between the web and the grinding medium during grinding.
According to the present invention, it is essential that the higher points, i.e. the xe2x80x9chillsxe2x80x9d. are ground away from the paper surface and for fulfilling this goal the grinding belts back support and the papers support must be built so that only higher level parts from papers surface are removed. Generally, the roughness of the surface, as measured in micrometers, is reduced by 10 to 90%, preferably about 40 to 60%, after grinding.
During grinding, the web is subjected to a grinding energy on the order of 700 to 14,000 J/m2, preferably about 2,000 to 8,000 J/m2. According to a particularly preferred embodiment, the web is subjected to 2,000-3,000 J/m2 grinding energy/micron roughness of the web. As mentioned above, the mechanical properties of the paper or board remain unchanged by the grinding according to the present invention. They can even be improved by the grinding as explained above. Thus, when the roughness of the surface is reduced by a maximum of 90% the strength properties of the web will remain essentially unchanged or they are improved. When the roughness of the surface is reduced by about 40 to 60% the tear strength is increased with at least 5% (preferably over 10%) in comparison to an untreated web.
A visual inspection of a paper treated by the present grinding method reveals that the opacity of the paper is not significantly changed when 40 to 60% of hills and similar irrregularities on the surface have been subjected to grinding. At the same time, the mechanical strength of the paper is excellent.
The pressure exerted on the web can vary within a wide large as long as no significant compressing of the paper takes place. This would otherwise weaken the mechanical strength of the web. Generally, the surface pressure of the grinding should be about 0.01 to 20 kPa, preferably about 1 to 10 kPa.
After the grinding it is advantageous to remoisturize the treated surface and press it slightly against a very smooth surface or against a moving smooth surface for getting all loose fibres and fines back to the surface. This treatment will even further smoothen the ground surface. For moisturizing, steam or water vapour can be used as well as a mist containing evenly distributed small droplet produced by, e.g., an ultrasonic treatment, and which can be attached to the surface by ionization methods.
In an article titled xe2x80x9cFriction in Wood Grindingxe2x80x9d (Paper and Timber, Vol. 79 (1997) No. 4) wood grinding with a grinding stone is discussed in some detail. The authors claim that a grinding speed of less than 7 m/s is totally ineffective and that only at speeds of 10 to 30 m/s the grinding stone will release some fibers from wood. At lower speed only some unwanted fibrillation will take place on the contact surface of wood.
The present invention is based on the opposite concept: we do not want to release whole fibers from the surface of the paper or board web, but instead only fibrils and loose parts of fibers. Therefore, the velocity difference can, according to the present invention, be in the range of 1 to 10 m/s and still satisfying results are obtained. However, according to another embodiment the higher the speed difference between the belt and paper or board to be grinded, the better the result. The best way to do it is to arrange the belt and web to be running in the same direction but with different speed. This provides for efficient removal of dust. High grinding speed is advantageous for two different reasons: firstly, it will prevent dust and fines from gathering on the belt and, secondly, at high speed the surface pressure can be kept low and melting of resins, lignin etc. does not take place on the surface and so the grinding belt or other grinding media surface will not to be blocked. The critical speed depends on the wood or pulp quality from which the paper or board has been made and also on the quality of the grinding particles on the grinding media surface. The grinding speed and pressure must nevertheless always be kept on a level where no local heating will happen to the extent that resins and lingnins are softened. Should this happen, the grinding medium would soon be clogged with fibres, resins, lignin and loose dust from the web.
According to a preferred embodiment, wherein a belt grinder comprising a dry belt of a polymeric material is used, the fibrous belt is friction electrified as a result of the grinding. Therefore, fibrils and fine particles released from the web by the grinding are rebound to the surface by electrostatic forces between the fibrils and the web. No dusting of the web takes place. The electrical loading of the surface can also be effected before grinding in order to increase the electrical load of the surface.
By treating the fibrous web with cationized starch or a similar cationic material, conventionally used for improving retention of pigments or fines on the wire of a paper or board machine, the cationic material will effectively bind fibrils loosened during the grinding process to the surface.
According to a further preferred embodiment, the ground surface, which as mentioned above, is usually faded or mat after grinding, can be made glossy by moisturizing it slightly with steam and pressing it against a smooth surface.
A paper or board treated according to the present invention can be coated or used as such optionally after glossing with a conventional calender or, preferably as explained above, after moisturizing. For coating purposes the paper can be provided with a polymer layer, a barrier layer, a laquer or with normal coating colours. These papers and board are particularly suitable for printing and writing and ink jet printing. Untreated optionally glossy-quality products are also suitable for packaging, wrapping and bagging purposes.
The following non-limiting example illustrates the invention: | {
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The present invention relates to an attachment system for forming a substantially planar wall structure, a connector to be used in the system, and a method of assembling the system to form the wall structure.
A variety of different techniques and systems are employed to form interior and exterior walls. Typically, the walls are formed by a number of individual panel members joined together by connector(s) mounted to a support structure. The panel members may be formed from metallic materials such as aluminum, thermoplastic materials, glass, or composites. The connectors vary depending upon the type of wall to be constructed and the type of support structure to which they are mounted. The following U.S. patents illustrate some of the various types of connectors and wall systems known in the art.
U.S. Pat. No. 3,071,215 to Gall relates to a system for forming an exterior curtain wall from a plurality of pre-assembled units, sections or panels. The panels are located and supported in position by a series of column members or side rails and a series of horizontal beam members including a top rail, a bottom rail and one or more intermediate rails. Hanger plates are used to join each side rail to a mounting member. Each side rail includes a base portion and a channel for receiving an edge portion of a panel. The channel is formed by a pair of horizontally spaced legs extending from the base portion and a pair of inturned flanges. The top, bottom and intermediate rails employ a similar construction to define a channel or channels for receiving an edge portion of a panel.
U.S. Pat. No. 3,199,258 to Jentoft et al. illustrates a vertical mullion support to be used in a system for constructing a wall from a plurality of panels where the central portion of each panel is inwardly bowed. The vertical mullion support comprises a base portion, a central web construction extending from the base portion, and an outboard end formed by a pair of spaced apart, diverging sidewalls. Each sidewall includes a pair of inwardly sloped flanges defining a panel edge receiving slot. The inwardly sloped flanges cause the panels to assume the desired inwardly bowed configuration. The support further comprises a cap member which is recived within a longitudinal opening defined by the spaced apart sidewalls. A groove is provided in each sidewall for receiving a locking member on the cap.
U.S. Pat. Nos. 3,548,557 to Downing, Jr. and 3,553,915 to Passovoy illustrate connectors for forming interior partition walls. In the Downing, Jr. system, each panel is provided with a web having a down turned end. The supporting studs are each provided with a pair of flanges for abutting against the interior surface of adjacent panels. The flanges each include a finger and a shoulder for engaging the down turned end of the panel web to support the panel. Passovoy joins adjacent panels to a supporting member by snapping a panel retaining clip having a bifurcated receptacle section onto the support member. The panels are held in position by a T-shaped member which has a leg inserted into the receptacle section.
Still other types of panel connectors are illustrated in U.S. Pat. Nos. 4,114,330 to Sukolics and 4,151,691 to Wendt. The Sukolics patent relates to a modular skylight system which employs multi-piece connectors to join adjacent skylight panels. Wendt illustrates a ceiling rail for supporting members used to form a hollow wall partition. The ceiling rail has a base portion and a plurality of downwardly extending flanges for defining panel edge portions receiving channels.
A different type of wall system is illustrated in U.S. Pat. Nos. 4,344,267 and 4,452,029, both to Sukolics, and co-pending, commonly owned, U.S. patent application Ser. Nos. 110,174, filed Oct. 19, 1987, and 110,421, filed Oct. 20, 1987, both to Hutchison. In this system, a panel connecting member is mounted to a support structure. The panel connecting member includes a base portion, a pair of outwardly extending legs and means on each leg for engaging down-turned edge portions of adjacent panel members. The system also includes an insert for insuring positive engagement between the down-turned panel edges and the connector.
Certain aluminum and thermoplastic composite panel materials because of their finish, chrome plating, or brittle paint cannot be folded without damaging or destroying the finish. Therefore, a different type of connector must be used when forming these panels into a wall structure. Ideally, the connector is one which is easy to install and easy to use. Many prior art connectors are often either difficult to install or cumbersome to use.
Accordingly, it is an object of the present invention to provide a system and method for forming a substantially planar wall from a plurality of panel members.
It is a further object of the present invention to provide a connector for use in the above system and method which is easy to install and simple to use.
It is still a further object of the present invention to provide a connector as above which lends itself to use with a wide variety of panels having a wide variety of finishes and with a wide variety of support structures.
These and further objects and advantages will become apparent from the following description wherein like reference numerals depict like elements. | {
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This invention relates to conveyor systems and, in particular, mobile conveyor machines for use with endless conveyor belts and hitching apparatus for use with such machines and other mobile machines.
Belt conveyors are well known and are efficient means for moving large quantities of materials such as ore, coal and granular stone over a predetermined distance extending either horizontally, vertically or both. One form of conveyor system known for mining applications is a system involving a series of conveyors mounted on wheels so as to make the system easily movable. Because of the manner in which mines are developed and extended, it may be necessary for a relatively long conveyor system to be moved along a substantially curved or zig zag course. Under such circumstances, it can be difficult and time consuming to move the conveyor system when required. It will also be appreciated that it may be necessary to move the conveyor system and to make adjustments to the system fairly frequently as the mining machine advances in a mine.
U.S. Pat. No. 5,366,059 issued Nov. 22, 1994 to Prairie Machine & Parts Mfg. Ltd. describes and illustrates a conveyor system comprising a plurality of conveyor vehicles connected together in the form of a train and also describes a steering system for steering this train of vehicles. All but one of the vehicles in the train has a single pair of steerable wheels with the vehicle at the outby end of the train (that is the end to which the mine material is being delivered) having two steerable wheels. Hydraulic cylinders are used to steer each of the pairs of steerable wheels and there is a control mechanism for controlling and coordinating these cylinders in order to set the steering angles of the pairs of wheels. In this known system, each pair of wheels is mounted on an axle and each pair is driven by an electric tram motor mounted along the longitudinal centre of the conveyor vehicle. One difficulty encountered with this known conveyor system is that the system is relatively high along most of the length of the train and therefore the ceiling of the region of the mine where the mining machine is operating must be reasonably high, for example over six feet, to accommodate this conveyor system. Moreover, in this known system, the height of each pair of wheels relative to the conveyor frame is not adjustable.
There is a need in the belt conveyor industry to provide a hitching apparatus for pivotably connecting one end of a conveyor vehicle or conveyor machine to an adjacent end of another conveyor vehicle or conveyor machine. In particular, it is desirable to provide a new hitching apparatus which can be provided at one end of a conveyor machine that has a desirable low profile in order that the machine, as well as other machines connected thereto, can be used in areas of mines or mine shafts that have a relatively low ceiling, for example, a ceiling that is less than six feet. Such low ceiling mine areas and mine shafts are relatively common and it will be appreciated that often, from a mine economic standpoint, it may be too expensive to simply increase the ceiling height in order to accommodate a mobile conveyor system.
In addition, there is a perceived need to provide a reliable hitching apparatus for a mobile machine such as a mobile conveyor wherein the pivot point between two adjacent mobile machines or mobile conveyors is located between the pair of wheels located adjacent one end of one of the machines in order to enable the conveyor machines to be steered properly using an automated steering system for the conveyor system which is operated by an operator of the system. | {
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A wireless communication device, such as a cellular phone or a tablet device, can be used to perform various types of communications, such as making voice calls, transmitting or receiving textual messages, and transmitting or receiving computer-readable files. The various types of communications can be carried out by one or more communication networks. One of the communication networks can be a wireless network operated by a service provider that provides communication services to a user of the wireless communication device.
A service provider network can be configured in an arrangement that requires the wireless devices to register with the service provider network prior to the device using the service provider network. The service provider network can be overloaded if a large number of devices, such as wireless communication devices, request registration with the network simultaneously or close to simultaneously and the service provider network attempts to process all of the registrations requests. A quality of service provided by the service provider network can be degraded when the service provider network is overloaded by processing a high quantity of registration requests.
Unless otherwise indicated herein, the elements described in this section are not prior art to the claims and are not admitted to be prior art by inclusion in this section. | {
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The present invention relates to a plastics processing machine, in particular to an injection molding machine or an extruder, and more particularly to a plastics processing machine having at least one component being controlled by a control device.
Nothing in the following discussion of the state of the art is to be construed as an admission of prior art.
German Offenlegungsschrift DE 199 58 790 C2 discloses a machine for making parts of plastic or rubber, whereby an electronic unit, which is mounted in a plug on the machine, forms part of the control device of the machine and assumes detection of the actual temperature value with linearization and cold-spot compensation. The connection between the electronic unit and the control device is realized via a field bus.
As a consequence of an ever increasing automation, machine tools, like e.g. CNC milling machines or presses, use so-called automated tool recognition systems. Hereby it is to be understood the encoding of replacement tools by means of a chip which either contains the tool number only, whereas the CNC has stored the tool-specific parameters for this tool number, or contains per se the tool-specific parameters. Such a system is described, for example, in the “interbus applications”, release 02/1998 by the INTERBUS Club. Through automated tool recognition the previously used so-called space encoding is improved and rendered flexible which involves the assignment to each tool of precisely one space where it is deposited. To provide each tool with its own chip and to provide the machine with a respective reading station is cost-effective only because of the very frequent change of tools in machine tools.
Plastics processing machines normally include a plurality of partly very complex components, among others a clamping unit, a feed and metering apparatus, a plasticizing unit or extruder. Within these components, oftentimes various configurations of elements are possible whose specific parameters must be taken into account by a control device of the machine when controlling the component. For example, a plasticizing unit or an extruder includes a screw rotating in a screw cylinder for plasticizing and thoroughly mixing the material to be processed. Depending on need, plastics processing machines may be outfitted with different configurations between screw cylinder and used screw which in turn has its own characteristics. Unlike machine tools, a configuration is involved here which oftentimes does not change oftentimes.
The crucial criteria for selection of screw and cylinder are i.a. the intended field of application and the nature of the material to be processed. The greatest transmittable torque, the greatest applicable speed, the greatest applicable injection pressure, and the greatest injection stroke depend for example on the selection of the configuration. This represents however only some of the variables that are determined by the structure of the screw, like e.g. the number and shape of the grooves and the length/diameter ratio, and by the properties of the used cylinder. Typical characteristics of a cylinder are for example the diameter, the surface finish, the number of external heating zones, i.e. the number of separately operable and heatable zones along the length extension of the cylinder, the heating or cooling capacity that can be introduced there, type and characteristics of the thermoelectric elements used as temperature sensors, to name only a few. In conformity with the screw to be used and the cylinder as well as the material to be processed, the possible areas of use of a screw cylinder combination is determined.
As all component-specific parameters must be considered when correctly operating a component by a control device of a plastics processing machine, the control programs running in the control device must be separately suited to each possible component configuration when shipped. This means for example in relation to the plasticizing unit which is used in many different screw-cylinder configurations a very complicated programming process for each delivered machine. This is also a major drawback in connection with possible changes of an existing screw-cylinder configuration, as can be encountered in the exceptional case during material change but in particular upon replacement of defective or worn screws by new ones. The continuous adjustment of the control software is also a source of errors as is any change of existing software.
Compounding this problem is the fact that this special need for customization up to now did not enable the use of a uniform control software which would be applicable for all offered components which are combined for various customers in a machine according to a modular concept, and especially for different screw-cylinder configurations. This is however of great interest in particular for certain diameter zones in relation to the screw, paired with certain second diameter zones in relation to the cylinder.
A further drawback resides in particular in connection with screw-cylinder configurations in the complicated wiring that is required when changing the used external heating zones and especially when exceeding a certain standard number in order to ensure correct temperature compensation by means of a compensating wiring. Such a temperature compensation is required when using thermoelectric elements as temperature sensors to avoid corruption of the voltage supplied by the thermoelectric elements.
It would therefore be desirable and advantageous to provide a possibility to allow application of numerous components in specific configuration, in particular plasticizing and injection units with various screw-cylinder configurations in plastics processing machines while requiring little program adjustments, and allowing use of a global control software which is as configuration-independent as possible. | {
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Iodide-iodine etching solutions have been employed to recover precious metals from ore and scrap materials and have since been employed in the electronic and jewelry making industries in the etching and stripping of precious metals. Use of iodide-iodine solutions avoid toxicity problems associated with the previously used cyanide etching solutions but are considered costly.
Methods to reclaim spent iodide-iodine etching solutions have been developed to decrease the costs associated with their use. U.S. Pat. No. 3,957,505 discloses a process that dissolves and precipitates gold in potassium iodide-iodine using a reducing agent and a buffer. The solution can then be regenerated through the use of an oxidizing agent. U.S. Pat. No. 5,137,700 discloses the use of a hydroidic acid and iodine solution or ammonium iodide and iodine solution for the recovery of precious metals. A reducing agent is added to the solution with a buffer and the precious metal is precipitated from the solution. The spent solution is then treated to either oxidize it to its original state or to precipitate out the elemental iodine which is then used to supply the components for a new etching solution. | {
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1. Field of the Invention
This invention is in the field of surgical instruments and more particularly in the field of vessel dilators.
2. Related Art
A leading cause of mortality and morbidity of surgical patients is hospital borne disease transmission between patients. There are many machines and procedures for sterilizing and cleaning surgical instruments, including autoclaving. Despite the severity and rigor of these machines and procedures, the cleaning of the instruments is less than optimal. Specifically, blood denatures and hardens in crevices or embeds onto restricted areas of an instrument such that there are deposits of blood that remain after cleaning. These deposits of blood that remain after cleaning contain live pathogens. The result being that there is a risk of the transmission of disease from patient to patient.
It is theorized that humankind will never be able to devise a machine and/or process that in an economical and practical manner will optimally clean surgical instrument. Accordingly, it would be desirable to have surgical instrument that are disposable without compromising the efficacy and the cost effectiveness of performing surgery.
One type of surgical instrument is a vessel dilator. As the name implies, a vessel dilator provides intra-luminal vessel dilation during surgery. Vessel dilators are frequently used during surgical procedures as aid in fine dissection and vessel anastomosis. A conventional vessel dilator can be conceptualized as a modified forceps having elongated parallel tips which are highly polished. The parallel tips are pressed together to provide a single tapered shaft. The tapered shaft is inserted into a vessel and the parallel tips are allowed to separate thereby dilating the vessel. As a vessel dilator is inserted into a vessel, the dilator helps to hold the vessel wall and to avoid suturing the back wall to the front wall of the vessel.
Another type of surgical instrument is an irrigation instrument. Often, when a vessel is to be sutured, the vessel must be irrigated using an irrigation instrument. Irrigation is used to prevent drying of tissue, to remove tissue debris and blood, to keep vessel ends open and prevent floating adventitia at vessel ends interrupting satisfactory microvascular suturing and anastomosis. Irrigation keeps the operative field clean and inhibits blood clotting inside the lumen of the blood vessel.
Another type of surgical instrument is a suction instrument. Suction keeps the operative field clean and inhibits blood clotting inside the lumen of the blood vessel.
Another type of surgical devise is a cauterization instrument. Cauterization seals vessels and arrest bleeding. One conventional cauterization instrument is a bipolar-type blood vessel coagulation/stanching devise. Such a conventional devise employs a spark gap methodology using high-frequency current ranging between 0.5 to 3 MHz. This bipolar type devise has two electrodes (active and inactive electrodes) which are provided at both ends of a pair of forceps that are held by hand. Electric current flows only through the living tissue held between the ends of the forceps. Since electric current to a patient is applied only to a limited portion to be coagulated, bleeding from a blood vessel can be stopped completely without injuring other tissues. More specifically, the cauterization effect of the devise is obtained by coagulating the blood vessel using localized heating caused by the high-frequency current flowing through the living tissue.
Another surgical procedure of relevance here is anastomosis. Anastomosis covers a variety of procedures in which blood vessels (or other tubular members) are joined or reconnected. Vessels may be joined in a variety of relative orientations, including end-to-side and end-to-end. Anastomosis is traditionally performed by suturing the vessels together at the juncture between them. Alternatives to suturing have been developed, in order to prevent thrombosis which tends to occur at the points of penetration of the sutures. One such alternative, particularly for larger vessels, involves mechanical connectors such as collars. A second alternative is the use of surgical clips which are applied along the vessel juncture to perform a holding function similar to that of sutures, without penetrating the vessel walls.
A surgeon alternates amongst dilation, irrigation, suction and cauterization, during vessel dissection and anastomosis, using separate dilation, suction, irrigation and cauterization instruments. The act of switching among these four instruments is time-consuming and can interrupt the surgeon's attention and concentration.
In Bayat, A., A Novel, Triple-Function Vessel Dilator, Plastic And Reconstructive Surgery, January, 2003, volume 111(1), pp. 501-502 (American Society of Plastic Surgeons) and in Bayat, A. et al., A Novel Irrigating Vessel Dilator for Microsurgery, Plastic and Reconstructive Surgery, September, 2001, Vol 108(3), pp. 798-799, Applicant herein invented a three functional vessel dilator performing the functions of dilation, irrigation and suction during vessel dissection and anastomosis. Still, when suturing a blood vessel or otherwise performing operative tasks, a surgeon must alternate between this three functional vessel dilator and a cauterization instrument. Alternating between these two instruments is time consuming and interrupts the surgeon's attention.
In patent application Ser. No. 11/471,067 upon which this application is a continuation-in-part and which is incorporated herein by reference as further referred to herein below, there is taught the ingenuity of a four function microsurgical instrument performing the functions of aspiration, irrigation, dilation and cauterization in a novel and unobvious design. Referring to FIG. 1 of application Ser. No. 11/471,067, the instrument has a body with forceps-like arms. A plunger valve extends perpendicular from the body in a direction away from a side region and is positioned for actuation by a user (see, FIG. 1, reference numerals 12 and 30). This ingenuous design advanced the art; but, there were stell needs for an instrument with even more enhanced ergonomics, better stability, ease of use and use which did require repositioning of a user's finger from gripping a forceps-like arm to contacting a plunger valve so at to actuate the valve.
Accordingly, there exists a need for an all-in-one, simple to use, easy to handle, lightweight, atraumatic macrosurgery and/or microsurgical instrument that improves the overall efficiency of operative procedures. There exists a need for a surgical instrument configured so that all the four functions of dilation, suction, irrigation and cauterization fit together in one instrument and enabling a surgeon to perform operative tasks without having to switch instruments. There is therefore a need for a four function vessel dilator performing the functions of dilation, irrigation, suction and cauterization for use, including, during vessel dissection and anastomosis. There exists a need for an instrument for microsurgery that provides the advantages of being small in size, being ergonomical, being all-in-one, eliminating the need for a surgeon to fumble around in switching between instruments, reducing time consumption and reducing frustration.
There exists a need for a surgical instrument possessing the functions of dilation, irrigation, aspiration and cauterization where the user is NOT required to reposition and move the user's finger from gripping a forceps-like arm to the finger contact area of an actuation means for controlling irrigation-fluid and aspiration-suction.
There exists a further need for a surgical instrument possessing the functions of dilation, irrigation, aspiration and cauterization where the mechanism for controlling irrigation-fluid and aspiration-suction occupies a small and minimized volume such that it is containable in an instrument for microsurgery.
There exists a further need for a surgical instrument possessing a valve that has a high level of ergonomics; in particular, there would be a biometrically comfortable force to actuate the valve, a short travel distance for actuation, non-awkward finger positioning and a high level of instrument support within the hand.
There is a need for a totally disposable instrument that is low in cost and avoids the transmission of pathogenic agents, because current sterilization techniques are not totally fail-safe.
The present invention satisfies these needs, as well as others, and generally overcomes the presently known deficiencies in the art. | {
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Sensors using an evanescent field have become extremely useful in the past few years. These sensors have been created to detect a wide variety of materials such as pesticides, pathogens, nucleic acids, gases, and disease markers such as the HER2 breast cancer marker. These sensors function by measuring the interaction of an evanescent field (a non-propagating near field optical wave) with a target.
Total Internal Reflection Photoacoustic Spectroscopy (TIRPAS) is a method that exploits the evanescent field of a laser pulse reflecting off a glass/sample interface to generate photoacoustic responses. Specifically, the photoacoustic responses are typically generated by light absorbing analytes in a fluid sample (typically a liquid) that is in contact with a prism in the event one or more of the analytes are within the penetration depth of the evanescent field because upon absorbing the light energy the temperature of the analyte rapidly increases causing a rapid expansion (typically thermo-elastic) that in turns results in the formation of acoustic waves that propagate through the sample to a sensor.
For example, TIRPAS has been employed to detect dyes in a sample. Hinoue et al., Photoacoustic Observation of Solid-liquid Interface by Means of Total Internal Reflection Technique, CHEMISTRY LETTERS, 225-228 (1983). Hinoue et al. used a laser pulse generated with an optically chopped continuous beam HeNe laser at 632.8 nm to detect Brilliant Blue FCF dye at different angles of incidence to generate the evanescent field with a lock-in amplifier, which only amplifies a specific frequency, to detect the resulting acoustic wave. Although TIRPAS is typically used to analyze liquid samples, it may be used on gaseous and solid samples. See, e.g., Muessig et al., Total Internal Reflectance Optoacoustic Spectroscopy, J. APPL. PHYS. 54(8), 4251-4253 (1983). Muessig et al. also used continuous laser irradiation but instead of using an optical chopper to produce laser pulses, Muessig et al. used an oscillator connected to a lock-in amplifier to produce laser pulses.
Although TIRPAS has been known for more than thirty years its use has been limited due to shortcomings. For example, the TIRPAS disclosed by Hinoue et al. was limited to detecting Brilliant Blue FCF dye, a relatively high absorption analyte. Thus, it is unable to provide meaningful detection of low absorption analytes such as those that may be present in biological samples. In view of the foregoing, a need still exists for system(s) and method(s) for conducting TIRPAS that reduces or eliminates one or more of the foregoing shortcomings. | {
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In general, in fabricating semiconductor integrated circuits (semiconductor devices), substrates such as semiconductor wafers as object to be processed under treatment repetitively undergo predetermined procedures of film formation and pattern etching to build a number of desired devices.
During a variety of process steps applied to a object to be processed (substrate), the object, such as semiconductor wafer (hereinafter referred to as “wafer(s)”), had to be transported among processing units from one to another, and the wafers were unavoidably exposed to the atmospheric air during transport. Certain portions of wafer surfaces exposed to the atmospheric air (e.g., exposed portions of silicon substrates at the bottoms of contact-holes, or exposed portions of metal layers at the bottoms of through-holes) often got into reaction with oxygen and moisture in the air, and made native oxide films. There was also the possibility of producing chemical oxides on exposed surfaces due to reactions of such exposed portions with chemicals during wet cleaning (e.g., RCA cleaning). Additionally, there was another possibility that wafer surfaces were contaminated with substances such as metals during the transport of the wafers among the processing steps and among processing units.
Such oxides including native oxide films and chemical oxides (referred to as “native oxides” hereinafter) and metal contaminants degrade semiconductor properties such as electric properties, and thus, it has been usual to perform surface treatment to the wafer surfaces to remove the oxides and metal contaminants from them and clean them.
A typical technique conventionally employed as surface treatment to remove native oxide films and other undesired substances was wet cleaning (e.g. RCA cleaning) which immersed wafers in a liquid chemical such as HF solution to remove native oxide films and others. However, along with progressively increased density of integration and miniaturization of semiconductor devices, their dimensions including line widths and diameters of contact-holes are getting more and more miniaturized, which results in, for example, increasing aspect ratios of contact-holes and reducing their diameters to an extent around 0.2 to 0.3 μm or even smaller (e.g., 0.12 μm). Miniaturization to that extent caused the problems that liquid chemicals failed to sufficiently impregnate minute contact-holes, or on the contrary, liquid chemicals in the contact-holes could not go out therefrom due to their surface tensions. These problems sometimes led to the fatal disadvantage that native oxide films developed at the bottoms of the contact-holes could not be sufficiently removed.
In treating a multi-layered structure through the wet cleaning, since its respective layers exposed along walls of contact-holes made therethrough were different in etching rate, it caused further problems, such as irregularities in level of the wall surfaces of the contact-holes.
FIGS. 8A and 8B of attached drawings illustrate a contact-hole 202 for making electrical contact to a drain and a source formed on a surface of a wafer W of silicon (Si), for example. Hole diameter D shown in FIG. 8A is in the range from 0.2 to 0.3 μm, approximately. Multi-layered wall surfaces of the hole 202 are defined by silicon oxide films (SiO2) of three layers, for example, which are stacked in different film formation steps. For example, the first SiO2 film 204 is formed by thermal oxidization on the surface of the wafer W, the second SiO2 film 206 is made of phosphor-doped glass by spin coating, and the third SiO2 film 208 is made of silica glass. In addition to that, as shown in FIG. 8A, a native oxide film 210 is produced at the bottom of the contact-hole 202.
In such a three-layer-stacked layer, the SiO2 films 204, 206 and 208 are different in etching rate relative to a liquid chemical during wet cleaning. After the native oxide film 210 is removed by the wet cleaning, as shown in FIG. 8B, irregularities 209 are produced due to differences in etching rate, or border areas between adjacent layers where the liquid chemical can seep more easily are excessively eroded (see notches in the drawing). This is also a problem involved in the conventional wet-cleaning technique.
To overcome the above-mentioned disadvantages in the existing wet-cleaning technique, various alternative methods called dry-cleaning techniques (etching techniques) have been proposed as a replacement for wet-cleaning techniques relying on liquid chemicals, which used an etching gas to remove native oxide films (see, for example, Japanese Patent Laid-Open Publication No. hei 4-206526 and Japanese Patent Laid-Open Publication No. hei 6-196455).
Typically used is sputter etching with argon gas and H2 gas a method of removing native oxide films by dry cleaning.
In a method for burying through holes of semiconductor wafers with a metal as disclosed in Japanese Patent Laid-Open Publication No. hei 4-206526 referred to above, native oxide films or others are removed by pre-treating base metals partially exposed in a preliminary processing chamber, especially treating oxidized films overlying the metal films by supplying and heating ClF3 gas. Then that method transports the pre-treated wafers from the preliminary processing chamber to a film deposition chamber by a transport means without exposing them to the atmospheric air to conduct selective CVD of metals.
In the method of processing the wafers as disclosed in the above-identified Japanese Patent Laid-Open Publication No. hei 6-196455, wafers are placed in an atmosphere of a mixed gas of ClF3 and H2, and ultraviolet rays are irradiated to the mixed gas to thereby remove native oxide films produced on the wafers without heating the wafers.
However, the prior art sputter etching techniques relying on argon gas and hydrogen gas had the possibility of damaging contacts in the wafers, and there was the demand for a dry-cleaning technique using a low energy.
Additionally, the known cleaning technique using ClF3 gas involved the following problems:
That is, there was the problem that chlorine, derived from the ClF3 gas used for the cleaning, corroded metal films and others on wafers, and the resultant products of the semiconductor devices were degraded in yield and reliability. Since ClF3 gas is a chlorine-contained gas, after wafer surfaces were cleaned by using ClF3 gas, chlorine remained on the wafers in form of chlorine atoms combined with silicon or metals existing on wafer surfaces, for example, and the residual chlorine corrode metal films and others (as wirings of semiconductor devices, for example) formed on the wafers. Therefore, it invited deterioration of electrical properties of semiconductor, and degraded the reliability and yield of semiconductor devices as finished products.
Furthermore, there was the problem that reaction by the ClF3 gas excessively progressed, inviting damages to wafers and degradation of the yield and reliability of semiconductor devices as finished products. More specifically, after wafer surfaces were cleaned by using ClF3 gas, not only native oxides but also insulating films of SiO2 and metal films of Al intentionally formed on the wafers were undesirably etched by reaction with the ClF3 gas. When insulating films serving as interlayer insulating films in semiconductor devices and metal films serving as wiring in semiconductor devices are excessively etched, the resultant semiconductor devices degrade in electrical properties, and this inevitably results in decreasing the reliability and yield of semiconductor devices as final products.
The present invention is directed to overcoming the above-mentioned problems involved in the conventional cleaning technique for object surfaces to be processed, and it is an object of the present invention to provide a surface processing method and an apparatus therefor, which can improve the reliability of final products when used in process steps of manufacturing semiconductor devices. | {
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There is an image sensor using an organic photoelectric conversion film as a photoelectric conversion element (for example, see Patent Literature 1). Since the organic photoelectric conversion film can simultaneously perform color separation and light reception as a thin film, an aperture ratio is high and an on-chip lens is basically unnecessary.
There is also an image sensor in which a photodiode is also formed in a silicon layer below an organic photoelectric conversion film and phase difference detection is performed by the photodiode of the silicon layer while an image is acquired by the organic photoelectric conversion film (for example, see Patent Literature 2). | {
"pile_set_name": "USPTO Backgrounds"
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Organs-on-chips are a promising means to test drug efficacy and interactions without the need for animal testing. However, there has been little thought into how multiple organ systems should be integrated to study multi-organ physiology. This invention addresses key issues in the measurement and control of multiple organ-on-chip systems.
The measurement systems, microfabricated devices, and analytical and modeling techniques developed over the past decade to instrument and control cancer, immune, yeast, and cardiac cells provide a unique opportunity to address some of the most fundamental issues in organ interactions and drug responses. This problem clearly requires a coordinated, interdisciplinary, high-technology approach, such as understanding the interaction between lung function and organ oxygenation, neuroimmune interactions, response to neural injury, cardiac arrhythmias, and development of new multimodal therapies. To date, there have been no demonstrations of methods for controlling and analyzing multiple organs-on-chips, particularly in a manner that allows a single design of controller and analyzer to be dynamically configured for a particular application or analysis.
Therefore, a heretofore unaddressed need exists in the art to address the aforementioned deficiencies and inadequacies. | {
"pile_set_name": "USPTO Backgrounds"
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There is a need for an optoelectronic semiconductor laser wherein a substrate mode is suppressed. | {
"pile_set_name": "USPTO Backgrounds"
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This invention relates to sensors, alarm systems and wireless devices. More particularly, but not exclusively, the present invention relates to a wireless sensing device, system and method that senses tilt movement when mounted to an object or person. | {
"pile_set_name": "USPTO Backgrounds"
} |
The subject system and method are generally directed to memory controllers having measures for error detection and correction. More specifically, the subject system and method provide for a memory controller that is executable to self-actuate a writeback transaction to effect corrected storage of data in a given memory device responsive to detection of correctable error in that data as stored. Preferably, such measures are sufficiently incorporated in the memory controller that the memory controller itself may generate the writeback transaction without intervention of the particular application program or other master computer program that it serves.
Memory controllers are well known in the art. They are implemented as digital circuits dedicated to controlling/managing the flow of data written to and read from one or more memory devices, and to preserve the same by periodically refreshing the memory as needed. They may be suitably formed as separate devices or integrated with a central processing unit or other main controller, and serve the memory storage and access needs of various control or user application ‘master’ operations processed thereby. Memory controllers implement the logic necessary to read from and write to various types of memory devices, examples of which include dynamic random access memory (DRAM), as well as electrically programmable types of non-volatile memory such as flash memory, and the like.
To minimize the consequences of data corruption due to random sources of error, various error detection and correction measures are employed in the art for the storage and retrieval of data from memory devices. One example of the various known measures is the use of an Error-Correcting Code (ECC). ECC measures are widely implemented in memory controllers heretofore known in various computer applications that may be particularly vulnerable to data corruption, or more generally in high data rate or other such applications where substantial immunity to data corruption is particularly important, and the added processing burden and complexity of ECC are not prohibitive. ECC measures generally involve adding redundant ECC bits to a transmitted data segment according to a predetermined code (of selected ECC format). These ECC bits are of parity-type, and permit the data segment to be properly recovered at the receiving end (by a receiver suitably configured for the given ECC format), even if certain correctable errors were introduced in the transmission or storage of that data segment. The degree to which the errors are correctable would depend on the relevant properties of the particular code being used.
Known memory controllers suitably configured in this regard execute with sufficient autonomy to relieve the master of the processing burden to carry out routine management of data flow to and from the given memory. They also relieve the master's burden of generating the necessary transaction(s) to carry out proper recovery of corrupted data segments stored in memory with correctable error. When it comes to actually remedying the corrupted storage of data, however, known memory controllers rely on conventional scrubbing transactions, which in turn rely on the master operation's interactively providing the read-modify-write commands for appropriate writeback of data. There is therefore a need for a memory controller system capable of sufficiently autonomous operation to self-actuate the writeback transactions needed to remedy the storage of corrupted data in memory as they are encountered. | {
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1. Field of the Invention
The present invention relates to polymers. More particularly, the invention pertains to novel and useful polymers comprising a carbon-oxygen backbone having a dioxycarbon moiety with a plurality of organic groups pendant from the dioxycarbon. The polymers are represented by the following general formula: ##STR2## WHEREIN R.sub.1 is a di, tri or tetravalent alkylene, alkenylene, alkyleneoxy, cycloalkylene, cycloalkylene substituted with an alkyl, alkoxy or alkenyl, cycloalkenylene, cycloalkenylene substituted with an alkyl, alkoxy or alkenyl, arylene, or a arylene substituted with an alkyl, alkoxy or alkenyl, R.sub.2 and R.sub.3 are alkyl, alkenyl, alkoxy, alkenyloxy, alkylene, alkenylene, alkyleneoxy, alkenyleneoxy, alkylenedioxy, alkenylenedioxy, aryloxy, aralkyleneoxy, aralkenyleneoxy, aralkylenedioxy, aralkenylenedioxy, oxa, or OR.sub.1 O with R.sub.1 defined as above; and wherein, (a) R.sub.1 is divalent when R.sub.2 and R.sub.3 are alkyl, alkenyl, alkoxy, or alkenyloxy, with at least one of R.sub.2 or R.sub.3 an alkoxy or alkenyloxy; (b) R.sub.1 is divalent when R.sub.2 and R.sub.3 are intramolecularly covalently bonded to each other and to the same dioxycarbon atom to form a heterocyclic ring or a heterocyclic ring substituted with an alkyl, alkoxy or alkenyl when R.sub.2 is an alkyleneoxy or alkenyleneoxy and R.sub.3 is an alkyleneoxy, alkenyleneoxy or alkylene; (c) R.sub.1 is divalent when R.sub.2 and R.sub.3 are intramolecularly covalently bonded to each other and to the same dioxy carbon atom to form a fused polycyclic ring or a fused polycyclic ring substituted with an alkyl, alkoxy or alkenyl when R.sub.2 is an oxa, alkyleneoxy or alkenyleneoxy and R.sub.3 is aryloxy, aralkyleneoxy, aralkenyleneoxy or aralkylene; (d) R.sub.1 is divalent when R.sub.2 or R.sub.3 is an OR.sub.1 O bridge between polymer backbones bonded through their dioxycarbon moieties, and the other R.sub.2 or R.sub.3 in an alkyl, alkenyl, alkyloxy, or alkenyloxy; (e) R.sub.1 is tri or tetravelent when R.sub.2 and R.sub.3 are covalently bonded to each other and to the same dioxycarbon atom to form a heterocyclic ring or a heterocyclic ring substituted with an alkyl, alkoxy or alkenyl when R.sub.2 is an alkyleneoxy or alkenyleneoxy and R.sub.3 is an alkyleneoxy, alkenyleneoxy or alkylene; (f) R.sub.1 is tri or tetravalent when R.sub.2 and R.sub.3 are covalently bonded to each other and to the same dioxy carbon atom to form a fused polycyclic ring or fused polycyclic ring substituted with an alkyl, alkoxy or alkenyl when R.sub.2 is an oxa, alkyleneoxy or alkenyleneoxy and R.sub.3 is aryloxy, aralkyleneoxy, aralkenyleneoxy or aralkylene.
The polymers provided by the invention include homopolymers, copolymers of the random and block types formed by reacting monomers or mixtures of preformed homopolymers and/or copolymers, branched polymers and cross-linked polymers. The invention also makes available to the art thermoplastic linear polymers when R.sub.1 is divalent, R.sub.2 and R.sub.3 are substituted with a noncross-linking group or are bonded intramolecularly; thermosetting cross-linked polymers when R.sub.1 is divalent and R.sub.2 or R.sub.3 is intermolecularly bonded between different polymeric backbones; and, thermosetting cross-linked polymers when R.sub.1 is tri or tetravalent and R.sub.2 and R.sub.3 are substituted with noncross-linking groups, or bonded intramolecularly.
2. Description of the Prior Art
The reaction of orthoesters with glycols leading to non-polymeric and other diverse products is known to the art in the references such as Ind. J. Appl. Chem., Vol. 28, No. 2, pages 53 to 58, 1965 wherein Mehrota, et al obtained monoethoxy-monoglycolate and triglycoxy-bisorthoformate by reacting orthoformate with hexamethylene glycol in molar ratios of one to one, and two to three to yield low molecular weight compounds. Similarly, Crank, et al in Aust. J. Chem., Vol. 17, pages 1392 to 1394, 1964, disclosed the reaction of triols with orthoesters including ethyl orthoformate with butane 1,2,4-triol, pentane-1,2,5-triol and pentane-1,3,5-triol to form monomeric bicyclic compounds. During the preparation of the bicyclic orthoesters by reacting ethyl orthoformate with triols, Crank, et al found that compounds produced from starting materials having a 1,2-diol structure also contained compounds having ethylene linkages. In a subsequent paper, Crank, et al Aust. J. Chem., Vol. 17, pages 1934 to 1938, 1964, developed this reaction into a synthetic procedure for the conversion of 1,2-diols into olefins. Later, DeWolfe in Carboxylic Ortho Acid Derivatives, 1970, published by Academic Press, Inc., New York, noted that carboxylic orthoesters are more reactive toward acid hydrolysis than almost any other class of compounds, and this high hydrolytic reactivity complicates their synthesis and storage. DeWolfe reported that the conversion of diols to cyclic orthoesters including alkoxydioxolane or alkoxydioxane, followed by acid hydrolysis, provides a method for monoacylating diols. More recently, Bailey reported in Polym. Prepr. Amer. Chem. Soc. Div. Polym. Chem., Vol. 13, No. 1, pages 281 to 286, 1972, that the polymerization of spiro orthoesters at ambient and elevated temperatures led to polyesters and polycarbonates of the structures [--CH.sub.2 CH.sub.2 CH.sub.2 COOCH.sub.2 CH.sub.2 O--].sub.n and [--OCH.sub.2 OCOOCH.sub.2 CH.sub.2 CH.sub.2 --].sub.n. | {
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U.S. Patent Publication No. 2012/0034150 A1, published Feb. 9, 2012, the disclosure of which is hereby incorporated herein in its entirety by this reference, discloses background information hereto.
Additional information is disclosed in the following documents, the disclosure of each of which is hereby incorporated herein in its entirety by this reference: 1. International Application No. PCT/US2013/00072, filed Mar. 15, 2013, for “Methods and Structures for Reducing Carbon Oxides with Non-Ferrous Catalysts,” which claims the benefit of U.S. Provisional Patent Application Ser. No. 61/624,702, filed Apr. 16, 2012, in the name of Dallas B. Noyes; 2. International Application No. PCT/US2013/00076, filed Mar. 15, 2013, for “Methods and Systems for Thermal Energy Recovery from Production of Solid Carbon Materials by Reducing Carbon Oxides,” which claims the benefit of U.S. Provisional Patent Application Ser. No. 61/624,573, filed Apr. 16, 2012, in the name of Dallas B. Noyes; 3. International Application No. PCT/US2013/00077, Mar. 15, 2013, for “Methods for Producing Solid Carbon by Reducing Carbon Dioxide,” which claims the benefit of U.S. Provisional Patent Application Ser. No. 61/624,723, filed Apr. 16, 2012, in the name of Dallas B. Noyes; 4. International Application No. PCT/US2013/00073, filed Mar. 15, 2013, for “Methods and Reactors for Producing Solid Carbon Nanotubes, Solid Carbon Clusters, and Forests,” which claims the benefit of U.S. Provisional Patent Application Ser. No. 61/624,753, filed Apr. 16, 2012, in the name of Dallas B. Noyes; 5. International Application No. PCT/US2013/00071, filed Mar. 15, 2013, for “Methods for Using Metal Catalysts in Carbon Oxide Catalytic Converters,” which claims the benefit of U.S. Provisional Patent Application Ser. No. 61/624,848, filed Apr. 16, 2012, in the name of Dallas B. Noyes; 6. International Application No. PCT/US2013/00081, filed Mar. 15, 2013, for “Methods and Systems for Capturing and Sequestering Carbon and for Reducing the Mass of Carbon Oxides in a Waste Gas Stream,” which claims the benefit of U.S. Provisional Patent Application Ser. No. 61/624,462, filed Apr. 16, 2012, in the name of Dallas B. Noyes; 7. International Application No. PCT/US2013/00078, filed Mar. 15, 2013, for “Methods and Systems for Forming Ammonia and Solid Carbon Products,” which claims the benefit of U.S. Provisional Patent Application Ser. No. 61/671,464, filed Jul. 13, 2012, in the name of Dallas B. Noyes; and 8. International Application No. PCT/US2013/00079, filed Mar. 15, 2013, for “Carbon Nanotubes Having a Bimodal Size Distribution,” which claims the benefit of U.S. Provisional Patent Application Ser. No. 61/637,229, filed Apr. 23, 2012, in the name of Dallas B. Noyes.
Solid carbon has numerous commercial applications. These applications include the longstanding use of carbon black and carbon fibers as filler material in tires, inks, etc.; use of various forms of graphite (e.g., pyrolytic graphite in heat shields); and innovative and emerging applications for carbon nanotubes (CNTs) and buckminsterfullerenes. CNTs are valuable because of their unique material properties, including strength, current-carrying capacity, and thermal and electrical conductivity. Current bulk use of CNTs includes use as additives to resins in the manufacture of composites. Research and development on CNTs is continuing, with a wide variety of applications in use or under consideration. One obstacle to widespread use of CNTs, however, has been the cost of manufacture. Conventional methods for the manufacture of solid carbon typically involve the pyrolysis of hydrocarbons in the presence of a suitable catalyst. Hydrocarbons are typically used as the carbon source, due to abundant availability and relatively low cost.
Carbon oxides, particularly carbon dioxide, are abundant gases present in ambient air and point-source emissions, such as exhaust gases generated by hydrocarbon combustion or off-gases generated by various manufacturing processes. Conventional aluminum manufacture, for example, involves the reduction of alumina (Al2O3). The process typically uses sacrificial carbon anodes to both deliver the electrical energy, and the carbon that reduces the aluminum oxides in the ore to produce the aluminum and carbon dioxide. Approximately two tons of carbon dioxide are produced for each ton of alumina that is reduced. Similarly, conventional steel manufacture involves the reduction of the oxides of iron present in iron ore or scrap iron. Carbon (in the form of coke, or in the form of sacrificial carbon anodes) is typically used as the reducing agent in the manufacture of steel, producing large amounts of carbon dioxide. Cement manufacture involves calcination, heating a raw material such as limestone (calcium carbonate) in a kiln, which liberates carbon dioxide. In addition to the carbon dioxide formed during calcination, carbon dioxide may be formed by the combustion of fuels (e.g., coal, natural gas, etc.) used to drive the calcination process, which may be either direct (combustion occurring within the calciner) or indirect (combustion occurring outside the calciner, with resultant heat transferred to the calciner). Worldwide, cement plants contribute about 5% of the total carbon dioxide emitted to the atmosphere from industrial processes. Cement manufacture is also associated with emission of various other waste products, including NOx (primarily NO), sulfur compounds (primarily SO2, with some sulfuric acid and hydrogen sulfide), hydrochloric acid, and particulate matter, including dust. The concentration of carbon dioxide in flue gases from cement plants is typically 15%-30% by volume, significantly higher than in flue gases from power plants (3%-15% by volume).
Concerns about greenhouse gases are encouraging industry and governments to find ways to minimize carbon dioxide production and its release into the atmosphere. Some methods for reducing carbon dioxide emissions involve capture and sequestration of the carbon dioxide (e.g., by injection into a geological formation). These methods, for example, form the basis for some “green” coal-fired power stations. In current practice, however, capture and sequestration of the carbon dioxide entails significant cost.
There is a spectrum of reactions involving carbon, oxygen, and hydrogen wherein various equilibria have been identified. Hydrocarbon pyrolysis involves equilibria between hydrogen and carbon that favors solid carbon production, typically with little or no oxygen present. The Boudouard reaction, also called the “carbon monoxide disproportionation reaction,” is the range of equilibria between carbon and oxygen that favors solid carbon production, typically with little or no hydrogen present. The Bosch reaction is within a region of equilibria where all of carbon, oxygen, and hydrogen are present under reaction conditions that also favor solid carbon production.
The relationship between the hydrocarbon pyrolysis, Boudouard, and Bosch reactions may be understood in terms of a C—H—O equilibrium diagram, as shown in FIG. 1. The C—H—O equilibrium diagram of FIG. 1 shows various known routes to solid carbon, including, carbon nanotubes (“CNTs”). The hydrocarbon pyrolysis reactions occur on the equilibrium line that connects H and C and in the region near the left edge of the triangle to the upper left of the dashed lines. Two dashed lines are shown because the transition between the pyrolysis zone and the Bosch reaction zone may change with reactor temperature. The Boudouard, or carbon monoxide disproportionation reactions, occur near the equilibrium line that connects O and C (i.e., the right edge of the triangle). In this zone, the Boudouard reaction is thermodynamically preferred over the Bosch reaction. The equilibrium lines for various temperatures that traverse the diagram show the approximate regions in which solid carbon will form. For each temperature, solid carbon may form in the regions above the associated equilibrium line, but will not generally form in the regions below the equilibrium line. In the region between the pyrolysis zone and the Boudouard reaction zone and above a particular reaction temperature curve, the Bosch reaction is thermodynamically preferred over the Boudouard reaction.
The use of carbon oxides as a carbon source in production of solid carbon has largely been unexploited. The immediate availability of ambient air may provide economical sources of carbon dioxide for local manufacture of solid carbon products. Because point-source emissions have much higher concentrations of carbon dioxide than ambient air, however, they are often economical sources from which to harvest carbon dioxide. | {
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Attachments for wheelchairs are disclosed herein. Wheelchairs provide mobility, and many wheelchairs are now motorized to increase that mobility. However, conventional wheelchairs and wheelchair attachments do not adequately provide users with access on demand to a fixture (e.g., a storage box, tray, planar surface, etc.) and do not allow the users to quickly and easily store the fixture when its use is no longer desired. | {
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The present invention relates to a super precise position detector, and more particularly, to a position detector for detecting a relative position between a mask and a wafer in a stepper X ray exposure apparatus in the order of 0.01 .mu.m by employing sector Fresnel zone plates.
In general, in a stepper X ray exposure apparatus, X ray microanalyzer and the like, it is impossible to set up an optical microscope right over an object to be analyzed, processed or worked in an ordinary manner so as to observe a desired point on the object, since the area right over the object is in the passage of X rays, electroncurrent and the like. For this reason, an area to be observed is observed obliquely with an ordinary optical microscope. At this time, due to the depth of a focus, the area coming into the field of vision is extremely limited. In addition, when a lens group is disposed in parallel with the surface of an area to be observed to obliquely observe an object to be observed, an image is formed by an oblique ray, resulting in that aberration increases and an image to be observed becomes indistinct.
With regard to a stepper X ray exposure apparatus of the above-mentioned arrangement, I have proposed a novel position detector in Japanese Parent Application No. Sho 63-162915 bearing the title "a position detector employing double linear Fresnel zone plates under illumination of multiple wavelength light". This position detector is to detect a relative position between a mask and a wafer which are spaced at a minute distance from each other in the direction of the optical axis of exposure X ray, in the direction perpendicular to the optical axis.
In this position detector, a mask and a wafer are respectively provided with a linear Fresnel zone plate (hereinafter referred to as LFZP) on which alignment marks are formed. The LFZPs are simultaneously illuminated by light rays of a plurality of wavelengths in the same direction from the upper in slant. An objective lens is disposed at an angle with the surface of the LFZPs on the opposite side with respect to the normal of LFZP. The lens has such an axial chromatic aberration that focal planes of the lens to light rays of a plurality of wavelengths agree with principal focal planes of the LFZPs by Fresnel diffraction to the plural wavelength rays which planes are different in position with each of the light rays, respectively. The Fresnel diffraction images on the principal focal planes of the LFZPs which planes are different in position to each of the plural wavelength rays incident upon the LFZP, are respectively focused through the objective lens on the same image forming planes of the objective lens in superposing relationship into a straight line. The Fresnel diffraction image in a straight line is converted into an electric signal by a linear sensor disposed on the image forming plane by a linear scanning operation in the direction perpendicular to the longitudinal direction of the image. A cylindrical lens is disposed between the objective lens and the linear sensor such that the Fresnel diffraction image in a straight line is compressed in the longitudinal direction thereof and is formed on the linear sensor. Then, a signal thus obtained by the linear sensor is handled to detect a relative position between the alignment marks on the LFZPs.
The principal focal plane (62) of the LFZP, however, as shown in FIG. 1, is parallel to the surface of LFZP, so that the principal focal planes of the alignment marks are parallel to the surface of the mask and wafer.
With such arrangement, to make a positional alignment servo operation possible during X ray exposure, it is necessary to enlarge a detection angle of a detection optical system disposed downstream of the objective lens with respect to the normal of the wafer (mask) plane. A large detection angle, however, deviates largely from an angle of 90.degree. between the optical axis of the detection optical system and the focal planes of the alignment marks to reduce the image forming area of the detection optical system with the result increasing distortion of an image due to an oblique image formation. As a result, it is very difficult to satisfactorily detect a light intensity of Fresnel diffraction image by the linear sensor with a good linearity and accuracy. As a solution to this disadvantage, it is conceivable to apply the improvement of a detection optical system proposed in Japanese Patent Publication No. Sho 44-23794, for example. The proposal has the following structure. In a detection optical system which observes an object surface from the upper right thereof, in order to form a real image perpendicular to the optical axis of an eyepiece on the optical axis, an objective lens is inclined with respect to the observing surface of the object and the eyepiece. Alternatively, a detection optical system is constructed so as to interpose a parallel ray portion within part of the optical path of the detection optical system. However, this system has the following disadvantages.
1 Design and manufacture of the optical system are cumbersome. PA0 2 Optical performance deteriorates. PA0 3 The resolving power falls due to decrease in optical performance. PA0 4 The detection angle of the optical system with respect to the surface of an object is limited. PA0 1 Pattern measuring method (contrast method, edge detection method), PA0 2 Method utilizing a diffracted light ray. These methods each have their advantages and disadvantages and there is little reason to choose between them. The present invention, however, provides a position detector employing a hybrid alignment system combining the advantages of the above 1 and 2. PA0 (1) Is is possible to make an oblique detection with an extremely simple optical system without interfering with an exposure X ray. PA0 (2) Since an oblique detection angle is determined by the design of an SFZP, a resolving power of the objective lens can be increased independently of the detection angle, so that a highly accurate detection is possible. PA0 (3) A servo control is enabled during an X ray exposure operation to detect alignment marks provided within the X ray exposure area. PA0 (4) Dependence upon process is extremely reduced. PA0 (3) There is no effect of variation in a gap between an X ray mask and a wafer and dependence upon the gap is extremely reduced. PA0 (6) High speed detection is possible. PA0 (7) The size of marks is reduced. PA0 (1) It is possible to perform a detection by largely inclining an objective lens of the detection optical system. PA0 (2) It is possible to incline the detection optical system so as to be outside the X ray exposure zone. PA0 (3) It is possible to detect the alignment marks during an X ray exposure operation. PA0 (4) It is possible to use the alignment marks within the X ray exposure zone. PA0 (5) In order to raise an optical resolving power of an objective lens of the detection optical system, the numerical aperture of the objective lens should be increased. On the other hand, the objective lens can be largely and simply inclined by employing SFZPs without interfering in the X ray exposure zone. Consquently, it is possible to set a limit of the numerical aperture which can be set with an oblique angle, to an very high value. PA0 (6) Since it ts possible to detect the alignment mark, which is provided within the X ray exposure zone, even during the exposure operation without interfering with the exposure X ray, a position of a mask/a wafer can be detected and corrected without evacuating the detection optical system during the X ray exposure operation. Since it is possible to effect a step repeating exposure on the whole surface of a wafer, an accuracy of alignment and a throughput operation can be remarkably improved. PA0 (7) Although the shape of alignment marks becomes somewhat complicated as compared with a linear Fresnel zone plate because a factor of angle is added to the alignment marks, the shape is much simpler than a circular Fresnel zone, so that a pattern change due to a process change seldom occurs. PA0 (8) Since the oblique incidence angle is determined by a SFZP and the detection optical system does not involve a special technique in design regarding the oblique incidence and difficulties in manufacturing, the design and manufacturing are simplified and hence a cost is reduced. PA0 (9) Both the illumination and detection systems can be constructed with a simple optical system. PA0 (10) The scope of detection is much wider than that of a diffraction light system. PA0 (11) In the detection optical system, PA0 (12) A detection accuracy is influenced by the nature of an image spot with a Fresnel zone plate as follows. PA0 In contrast, an oblique incidence is utilized in a position detector employing SFZPs, so that it is possible to completely shut out a spot produced by a ray passing through a mask by providing a window zone and a shielding zone, for example. There is no effect of variation in a gap between a mask and a wafer, resulting in a stable and accurate detection.
Consequently, it is not preferred even if the above proposal is applied to the foregoing position detector employing double linear Fresnel zone plates. | {
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Optical fibers can be coupled by melting their ends into lenses and placing the lenses in alignment and a predetermined distance apart. A lens can be formed by placing the tips of a pair of electrodes on opposite sides of a fiber end portion and establishing an arc between the electrodes that melts the fiber end portion into a lens. Early experiments by applicant involved the establishment of a DC arc of constant current, at a current amplitude continued for a period of time which resulted in a lens of a diameter greater than 25% of the fiber diameter and preferably about 50% greater than the fiber diameter. While the lens produced in this manner was able to couple light from one optical fiber to another, its mechanical reliability was not as great as hoped for. It was found that the lensed fiber had a weak spot lying a short distance behind the root of the lens, where the fiber was most likely to break. In pull tests, for example, the tensile strength of the fiber immediately behind the lens was only 40% of the tensile strength of the rest of the fiber. Also, multiple microscopic crevices could be observed in the lens surface, which could absorb moisture and develop cracks in the lens.
The use of an electric arc to melt the fiber into a lens was initially patterned on the use of electric arcs in fusing the ends of abutting optic fibers to splice them. In splicing, however, the fiber ends are merely softened with minimum deformation rather than being melted into balls, and in splicing problems are not encountered as to great weakening of the fiber behind the spliced ends or in the development of crevices which can cause damage to the fiber end.
In splicing, an arc of several milliamperes may be applied for a period of perhaps two seconds, to soften the ends of abutting fibers to splice them. An AC arc, which may be of low frequency, may be applied to produce a more uniform arc. When a similar setup was used in an attempt to melt an optic fiber into a lens, but with a higher current, the lensed region was found to be fairly brittle and to exhibit considerable crevices. A system for using an electric arc to melt a fiber end portion into a lens, which produced lensed fibers of high strength and smooth surfaces having a minimum amount of crevices, would be of considerable value. | {
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This application is based upon and claims the benefit of priority from the prior Japanese Patent Applications No. 11-135821, filed May 17, 1999; No. 11-163482, filed Jun. 10, 1999; No. 11-354417, filed Dec. 14, 1999; and No. 2000-121198, filed Apr. 21, 2000, the entire contents of which are incorporated herein by reference.
The present invention relates to a near field optical microscope and a probe for the near field optical microscope which detect light scattered by a probe entering into a near field to obtain information concerning the surface of a sample.
A scanning probe microscope (SPM) is a generic name of an apparatus in which, when a probe is set 1 xcexcm or less close to a sample surface, the probe is let scan in the X- and Y-directions or X-, Y-, and Z-directions while detecting a correlative effect caused between both the probe and the sample surface, thereby to carry out two-dimensional mapping of the correlative effect. For example, scanning probe microscopes include a scanning tunneling microscope (STM), an atomic force microscope (AFM), a magnetic force microscope (MFM), and a scanning near-field optical microscope (SNOM).
Among them, developments of the SNOM as an optical microscope having a resolution which exceeds the diffraction limit by detecting near field light formed near a sample has been eagerly promoted after the later half of 1980s to achieve application use for fluorescence measurement of a bionic sample, evaluation of an element (various characteristic evaluations of dielectric light guide paths, measurement of light emission spectrums of semiconductor quantum dots, evaluation of various characteristics of semiconductor laser, etc.).
The SNOM is basically an apparatus which sets a sharp probe near a sample with light illuminated thereon and detects a field (near field) of light near the sample.
The U.S. Pat. No. 5,272,330 granted to Bezig et al. on Dec. 21, 1993 discloses a SNOM in which light is introduced to a probe having a narrowed top end, thereby to generate a field of light localized near a very small opening at the top end of the probe, and this is brought into contact with a sample, to illuminate a very small part of the sample. Transmitted light is detected by an optical detector provided below the sample, and two-dimensional mapping of an intensity of transmitted light is carried out.
The SNOM uses a rod-like probe such as an optical fiber or glass rod which has a top end processed to be narrow or a crystalline probe.
A rod-like probe covered with a metal film except the top end thereof has already been commercially available as an improved type of the probe.
An apparatus using this probe has an improved resolution in the lateral direction in comparison with an apparatus using a probe not coated with metal.
Meanwhile, the AFM has been most widely spread as an apparatus for obtaining topography information of the sample surface among SPMs.
The AFM detects a displacement of a cantilever which shifts in accordance with a force acting on a probe when the prove supported on the top end of the cantilever is set near a sample surface, for example, by an optical displacement sensor, thereby to obtain indirectly information concerning concaves and convexes of the sample surface.
One of the AFMS is disclosed in the Japanese Patent Application KOKAI Publication No. 62-130302.
The technique of measuring concaves and convexes on a sample by detecting a correlative force between the sample and the top end of the probe is utilized for other SPM apparatuses and is used as a means for carrying out so-called regulation.
N. F. van Hulst et al. has proposed a new SNOM which uses an AFM cantilever made of silicon nitride and detects optical information of a sample while measuring concaves and convexes of the sample by AFM measurement, in xe2x80x9cAppl. Phs. Lett. 62(5)xe2x80x9d, P. 461 (1993).
In this apparatus, the sample is set on an internal total reflection prism and the sample is illuminated with a He-Ne laser beam from the total reflection prism side, so the sample is excited and an evanescent optical field is formed near the sample surface.
Subsequently, a probe supported on the top end of the cantilever is inserted in the evanescent optical field, and evanescent light as a localized wave is converted into scattered light as a propagation wave. A part of this light is propagated inside a silicon-nitride-made probe which is substantially transparent with respect to the He-Ne laser beam and passes to the back side of the cantilever.
This light is condensed by a lens provided above the cantilever and enters into a photomultiplier tube through a pinhole provided at a position conjugate with the top end of the probe with respect to the lens. A SNOM signal is outputted from the photomultiplier tube.
While detecting this SNOM signal, displacement of the cantilever is measured by an optical displacement detection sensor. For example, a piezoelectric scanner is subjected to feedback control such that the displacement is maintained at a regulated constant value.
Accordingly, during one scanning, SNOM measurement is carried out based on a scanning signal and a SNOM signal and AFM measurement is carried out based on a scanning signal and a feedback control signal.
In the SNOM of an aperture type disclosed by Betzig et al., the probe should be subjected to metal coating to obtain a high resolution in the lateral direction.
However, it is not easy to manufacture uniformly a large quantity of probes each having an opening at the top end and coated with metal
A resolution exceeding a resolution which can be realized by an ordinary optical microscope is required for a SNOM which is expected to have a super resolution. To realize the super resolution, the diameter of the opening at the top end of the probe must be 0.1 xcexcm or less or preferably 0.05 xcexcm or less.
An opening having a diameter of these values is very difficult to prepare with excellent reproductivity.
In addition, since the amount of light which enters into the probe through the opening decreases in proportion to square of the radius of the opening, the light amount to be detected is reduced so that the S/N ratio is deteriorated, if the opening diameter is reduced for the purpose of improving the resolution of an SNOM image in the lateral direction. Thus, there is a problem of trade-off.
Hence, a proposal has been made for a new SNOM (scattering-type) SNOM which uses a feature that high-diffraction dielectric material or metal strongly scatters near-field light without forming an opening at the top end of the probe.
In this SNOM, no opening is required at the top end of the probe so that there is not the problem of trade-off and the difficulty of forming the opening.
Kawata et al. disclose a scattering-type SNOM in the Japanese Patent Application KOKAI Publication No. 6-137847.
In this SNOM, the evanescent light formed on the sample surface is scattered by a needle-like probe and is thereby converted into propagation light. This propagation light, i.e., scattered light is detected by a condenser lens and a photodetector provided in a side of the probe, and optical information is obtained, based on a detection signal thereof.
Further, Kawata et al. disclose an apparatus in which a metal probe of the STM is used as its probe and propagation light generated due to scattering of evanescent light generated on the sample surface by the top end of the metal prove is observed from the lateral side of the sample and probe while controlling the distance between a sample and the probe by the STM, so STM observation and SNOM observation can be achieved, in xe2x80x9cDAI-42-KAI NIHON OHYOH BUTSURIGAKU KANKEI RENGOH KOENKAI (preliminary report compilation No. 3, page 916, March 1995)xe2x80x9d.
Also, Kawada et al. further reports that the SNOM observation can be achieved even by multiple scattering of propagation light entering obliquely from the upside of the sample, between the top end of a metal probe and a sample, in place of the evanescent light, in xe2x80x9cDAI-43-KAI NIHON OHYOH BUTSURIGAKU KANKEI RENGOH KOENKAI (preliminary report compilation No. 3, page 916, March 1996)xe2x80x9d.
Bachelot et al. also report a scattering-type SNOM depending on propagation light from the upside without using the probe having an opening, in xe2x80x9cOpt. Lett. 20 (1995), p. 1924xe2x80x9d.
Toda et al. disclose a scattering-type SNOM which uses an micro cantilever made of silicon for AFM so as to use a dark field illumination system.
Since an AFM image with a high resolution can be obtained by this AFM cantilever made of silicon and also the diffraction rate is high, the scattering efficiency of light is high so advantages can be obtained for the scattering type SNOM probe.
The scattering type SNOM probe is constructed in a structure in which the probe becomes fatter from the top end toward the bottom portion supporting the probe.
In addition, light is scattered by the part within a range of one wavelength from the top end of the probe.
Therefore, light is scattered not only by the top end of the probe but also by a part which is fatter than the top end.
A signal depending on the scattered light from the fatter part lowers the high-resolution performance of an SNOM image.
Also, since the cantilever made of silicon for AFM described above has a structure in which the probe projects from the top end of a plate-like lever, there is a drawback that scattered light is blocked by the lever part so that the scattered light cannot be used efficiently.
Angular resolution of the scattered light is also a factor important to attain high resolution. The angle which can be used is limited due to the reasons described above.
In addition, in many of existing apparatuses, an objective lens used for both the optical microscopic observation and scattering signal collection is provided above a sample, and therefore, there is a drawback that an apparatus for measurement depending on the angle of scattered light cannot be provided.
In the scattering type near field optical microscope (scattering type SNOM) utilizes a feature that light illuminated on a probe causes strong scattering at the top end portion due to an effect of electric field concentration to a sharp top end of a probe, to illuminate a very small portion of a sample in close contact to the probe with the scattered light. By taking in this light while scanning the sample, an image exceeding the diffraction limit is obtained.
With respect to the shape of the probe, probes for AFM and STM have been conventionally used but attention has not been particularly paid except the condition that the top end is sharp.
A probe for the scattering type SNOM has a structure in which the probe is fatter from the top end toward a portion closer to the base part supporting the top end. Although light is scattered most strongly by the sharp portion at the top end of the probe, the light is also scattered by the part within one wavelength or so from the top end.
Therefore, light is scattered not only by the top end of the probe but also by the part which is fatter than the top end.
A signal depending on the scattered light from the fatter part deteriorates the high-resolution performance of a SNOM image.
Sugiura et al. disclose a SNOM which uses a very small gold globe supported by a laser trap, as a scattering probe, in xe2x80x9cOpt. Lett. 22 (1997), P. 1663xe2x80x9d.
In this SNOM, drawbacks as described above need not be considered but the force of holding the very small gold globe is weak so that imaging takes a very long time.
Also, samples that can be observed are limited because of underwater operation.
The present invention has an object of providing a near-field optical microscope as a SNOM which can obtain a high-resolution SNOM image and can operate in the air be extremely excluding influences from scattered light from portions other than a probe, and the probe for the near-field optical microscope.
Also, the present invention has an object of providing a near-field optical microscope which can detect scattered light over a wider angle range by arranging the structure of a cantilever, and the cantilever for the near-field optical microscope.
To achieve the above objects, according to the present invention, there is provided a near-field optical microscope comprising: an illumination part for illuminating a sample surface with light; a probe provided at a position near the sample surface illuminated with the light; a light detection part for detecting light scattered by the probe; and a scanning part for scanning the sample and a top end of the probe relatively to each other, wherein the top end of the probe is a top end of an extending part extending in one direction from a body of the probe, in a side of the top end of the extending part, the extending part is at most three times or less as thick as a tope end diameter, over a length of a wavelength of the illuminating light, and the near-field optical microscope further comprises means for vibrating the probe in a lengthwise direction of the extending part.
Also, to achieve the above objects, according to the present invention, there is provided a probe used for a near-field optical microscope, comprising: a probe body; and an extending part extending in one direction from the probe body, wherein in a side of a top end of the extending part, the extending part is at most three times or less as thick as a top end diameter, over a length of 700 nm from the top end.
Also, to achieve the above objects, according to the present invention, there is provided a near-field optical microscope comprising: an illumination part for illuminating a sample surface with light; a cantilever having a probe and a probe hold part, with a top end part of the probe positioned near the sample; and an objective optical system for receiving scattered light generated at a top end part of the probe and caused from the illuminating light, wherein the top end part of the probe is in a view field of the objective optical system without being shielded.
Also, to achieve the above objects, according to the present invention, there is provided a cantilever which can be used for a near-field optical microscope, comprising: a hold part extending in one direction; and a probe positioned at an end part of the hold part, wherein a top end of the probe is positioned further outside a top end of the hold part in the direction in which the hold part extends.
Also, to achieve the above object, according to the present invention, there is provided a near-field optical microscope comprising: light illumination means for illuminating a sample surface of a sample with light; a probe having a top end provided at a position near the sample surface which is illuminated with the light; light detection means for detecting scattered light scattered by the probe; and scanning means for scanning the sample and the top end of the probe relatively to each other, wherein a top end diameter of the prove is equal to or smaller than xc2xc of a wavelength of the light illuminating the probe, and where a length of a range illuminated with the light from the light illumination means is z0, the wavelength of the illuminating light is xcex, a maximum value of a diameter of the probe is dmax within a range from a top end of the probe to a distance z0, and the top end diameter of the probe is d0, the diameter of the probe monotonously increases from the top end to the distance z0, and dmaxxe2x89xa7d0(z0+xcex/2)/(xcex/2) is given.
Also, to achieve the above object, according to the present invention, there is provided a near-field optical microscope comprising: light illumination means for illuminating a sample surface of a sample with light; a probe having a top end provided at a position near the sample surface which is illuminated with the light; light detection means for detecting scattered light scattered by the probe; and scanning means for scanning the sample and the probe relatively to each other, wherein a top end diameter of the prove is equal to or smaller than xc2xc of a wavelength of the light illuminating the probe, and where a length of a detection range of the light detection means is z0, the wavelength of the illuminating light is xcex, a maximum value of a diameter of the probe is dmax within a range from a top end of the probe to a distance z0, and the top end diameter of the probe is d0, the diameter of the probe monotonously increases from the top end to the distance z0, and dmaxxe2x89xa6d0(z0+xcex/2)/(xcex/2) is given.
Also, to achieve the above objects, according to the present invention, there is provided a probe used for a near-field optical microscope, comprising: a probe body; and an extending part extending in one direction from the probe body, wherein a top end diameter of the extending part is equal to or smaller than xc2xc of a wavelength of light illuminating the probe, and where a length of a range illuminated with the light from the extending part is z0, the wavelength of the illuminating light is xcex, a maximum value of a diameter of the extending part is dmax within a range from a top end of the extending part to a distance z0, and the top end diameter of the extending part is d0, the diameter of the extending part monotonously increases from the top end to the distance z0, and dmaxxe2x89xa6d0(z0+xcex/2)/(xcex/2) is given.
Additional objects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out hereinafter. | {
"pile_set_name": "USPTO Backgrounds"
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The present invention relates in general to a humidity sensor alarm unit, and it more particularly relates to a fail-safe alarm unit which activates an alarm circuit when the relative humidity changes to an out-of-limit condition or when a malfunction such as a power failure or cut cable occurs.
Electrical humidity sensors have been employed for detecting relative humidity. Such sensors employ hygroscopic film which changes its electrical resistance rapidly with minute changes in moisture conditions. While such humidity sensors have been employed successfully for many different applications, it would be highly desirable to have a humidity sensor detecting an out-of-limit humidity condition or when certain malfunction conditions occur, such conditions including the humidity sensor circuit being shorted or opened. In this regard, the alarm signal should be generated when a cable is cut or the humidity sensor is missing. Also, the alarm signal should be generated when a power failure occurs, or when any circuit component of the alarm unit should fail. | {
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This invention relates generally to organic light emitting device (OLED) displays.
In an OLED display, an organic light emitting material is subjected to an appropriate potential, causing the material to emit light. Organic light emitting device displays may be formed of a plurality of components including a glass substrate. In one form of OLED display, the light emitting material is deposited on a glass substrate. The glass substrate may then be joined with another layer, such as ceramic layer, that provides for interconnections to various driver circuits and the like.
Generally, the light emitting material is formed on the back side of the glass substrate. Thus, the emitted light shines through the glass substrate to the viewer. Thinner glass substrates improve display contrast, resolution and improve the ability to interface with microlenses.
Current organic light emitting device displays employ glass substrates with thicknesses of between 0.5 to 0.7 millimeters (thicker glass substrates). These thicknesses are compatible with pixel spacings of 1.5 millimeters and greater. As pixel pitch becomes smaller, the use of thinner glass substrates becomes more desirable. However, thinner glass substrates (less than 0.5 millimeters) including those as thin as 0.2 millimeters are not amenable to volume manufacturing. In particular, the use of thinner glass substrates raises material handling problems resulting in lower yields.
Conventional glass handling machines are not specifically adapted for relatively thin glass substrates. Thus, to handle such thinner glass substrates, special equipment may be required, increasing the cost of display manufacture.
For a variety of reasons, it would be desirable to have organic light emitting displays that use thinner glass substrates.
Thus, there is a need for better ways to enable the use of thinner glass substrates for forming OLED displays. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The present invention generally relates to an ultrasonic receiving apparatus for receiving ultrasonic waves. More specifically, the present invention is directed to an ultrasonic diagnosing apparatus to be used in medical diagnoses by receiving ultrasonic waves from biological bodies with employment of such an ultrasonic receiving apparatus.
2. Description of a Related Art
In conventional ultrasonic diagnosing apparatus, while both ultrasonic transmitting means and ultrasonic receiving means use the same systems, one-dimensional sensor array is generally employed which includes elements (vibrators) for transmitting/receiving ultrasonic waves. The vibrators are realized by using piezoelectric ceramics which is typically known as PZT (Pb(lead) zirconate titanate), or by using a polymer piezoelectric element such as PVDF (polyvinyle difluoride). Furthermore, such a one-dimensional sensor array is mechanically moved so as to acquire two-dimensional images, and those two-dimensional images are synthesized with each other, so that a three-dimensional image is obtained.
However, since there is a time lag along the mechanically moving direction of the one-dimensional sensor array in accordance with this method, tomographic images acquired at different time instants are synthesized with each other, and therefore, the synthesized image becomes blurred. As a result, this conventional method is not suitable for imaging objects to be inspected such as living bodies, for instance, in such a case where ultrasonic echo observations are carried out by employing the above-described conventional ultrasonic diagnosing apparatus.
In order to acquire a three-dimensional image having a high image quality by using ultrasonic waves, a two-dimensional sensor array capable of acquiring a two-dimensional image without being mechanically moved is necessarily required. For this reason, such a method of manufacturing a two-dimensional sensor array with employment of the above-described PZT or PVDF has been considered. In such a case where the above-described PZT or PVDF is employed so as to manufacture such a two-dimensional sensor array, elements must be processed in very fine manners, and also, a very large number of very fine elements must be connected by using wiring lines. However, it is practically difficult to process these elements in a finer manner, and also to manufacture these elements in a higher integration, as compared with the presently-available very fine processing manner and element integration method.
Also, even when these problems could be solved, there are other problems. That is, crosstalk between elements would be increased, electric impedance of elements connected by very fine wiring lines would be increased which deteriorate an S/N ratio thereof, and electrode portions of these very fine elements would be easily destroyed. Under such a circumstance, it is practically difficult to realize such a two-dimensional sensor array with employment of PZT or PVDF elements.
On the other hand, as another ultrasonic sensor without using a piezoelectric material such as PZT, an optical detecting type sensor is known in this field, by which an optical fiber is utilized and an ultrasonic wave is converted into an optical signal to be detected. As such an optical detecting type ultrasonic sensor, the below-mentioned ultrasonic sensors are reported, namely, an optical detecting type sensor using the fiber Bragg grating (will be abbreviated as an xe2x80x9cFBGxe2x80x9d hereinafter) described in xe2x80x9cUnderwater Acoustic Sensor with Fiber Bragg Gratingxe2x80x9d written by TAKAHASHI et al. in National Defense Academy (Japan), see OPTICAL REVIEW Vol. 4, No. 6 in 1997, p. 691-694; and an optical detecting type sensor using the Fabry-Perot resonator (will be abbreviated as an xe2x80x9cFPRxe2x80x9d hereinafter) described in xe2x80x9cFabrication and Performance of a Fiber Optic Micro-Probe for Megahertz Ultrasonic Field Measurementsxe2x80x9d written by UNO et al. in Tokyo Institute of Technology, see T. IEE Japan, Vol. 118-E, No. 11 in 1998, p. 487-492.
If such a two-dimensional sensor array is manufactured by employing these ultrasonic sensors, there are such merits that electric-wiring works to a large number of very fine elements are no longer required, and furthermore, higher sensitivities can be obtained. However, this two-dimensional sensor owns another problem that since this ultrasonic sensor itself is made in high cost, manufacturing cost of a two-dimensional sensor is increased, and also, manufacturing cost of an ultrasonic receiving apparatus using the two-dimensional sensor array is increased.
The present invention has been made to solve the above-described problems. A first object of the present invention is to provide an ultrasonic receiving apparatus capable of detecting an ultrasonic wave in a two-dimensional manner without necessities of electric-wiring works to a large number of very fine elements and without increase of crosstalk and impedance, and furthermore, to manufacture the ultrasonic receiving apparatus in low cost. Also, a second object of the present invention is to provide an ultrasonic diagnosing apparatus capable of acquiring either a two-dimensional ultrasonic image or a three-dimensional ultrasonic image by using the above-described ultrasonic receiving apparatus.
To solve the above-explained problems, an ultrasonic receiving apparatus according to one aspect of the present invention comprises: an ultrasonic detecting element having a reception plane capable of receiving ultrasonic waves, for modulating light on the basis of ultrasonic waves applied to respective positions of the reception plane; and a photodetector having a plurality of pixels, for detecting light output from corresponding positions of the ultrasonic detecting element.
Also, an ultrasonic diagnosing apparatus according to one aspect of the present invention comprises: a drive signal generating circuit for generating the drive signals; transmission means for transmitting ultrasonic waves in response to drive signals; reception means including an ultrasonic detecting element and a photodetector, the ultrasonic detecting element having a reception plane capable of receiving ultrasonic waves and modulating light on the basis of ultrasonic waves applied to respective positions of the reception plane, the photodetector having a plurality of pixels and detecting light output from corresponding positions of the ultrasonic detecting element to thereby output detection signals; signal processing means for receiving the detection signals output from the reception means to process the received detection signals; control means for controlling both generation timing of the drive signals and acquisition timing of the detection signals; image processing means for constructing image data on the basis of an output signal of the signal processing means; and an image display unit for displaying thereon an image on the basis of the image data.
According to the present invention, since the ultrasonic detecting element having the ultrasonic reception plane including positions which correspond to a plurality of pixels of the photodetector is employed, such an ultrasonic receiving apparatus can be manufactured in low cost. That is to say, this ultrasonic receiving apparatus is capable of detecting the ultrasonic waves in a two-dimensional manner without necessities of electric-wiring works to the large number of very fine elements and without increase of crosstalk and impedance. Accordingly, an ultrasonic diagnosing apparatus capable of acquiring a two-dimensional or three-dimensional ultrasonic image with better qualities can be realized by employing such an ultrasonic receiving apparatus. | {
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A variety of different types of water purification and dispensing systems are known. Some utilize recirculation of water held in a reservoir to enhance the purity of the water in the reservoir. The recirculation can be coupled with additional treatment, such as ultraviolet sterilization, to further enhance the purity of the water. An example of a system that utilizes recirculation and ultraviolet sterilization is disclosed in U.S. Pat. No. 4,969,991.
Many of these known systems utilize multiple pumps to achieve water movement, as well as complicated valve systems to control the flow of water. This adds complexity as well as added cost to these systems.
There is, however, a continuing need for an improved water purification and dispensing apparatus. | {
"pile_set_name": "USPTO Backgrounds"
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This invention relates to bonding of fully-fabricated semiconductor devices onto other fully-fabricated semiconductor devices so as to produce integrated units, and particularly to bonding fully-fabricated photonic elements, such as GaAs/AlGaAs multiple quantum well (MQW) modulators, onto fully-fabricated integrated circuit (IC) chips such as Si or even GaAs.
Integration of photonic devices with silicon IC chips makes it possible to combine the advantages of each. Among photonic devices, GaAs/AlGaAs multiple quantum well (MQW) modulators are particularly beneficial as input/output (I/O) elements on IC chips because they have a high absorption coefficient of light and can serve as both receivers and transmitters. They typically operate at an optical wavelength (.lambda.) of 850 nm (nanometers).
Growing GaAs/AlGaAs on fully-fabricated IC chips has proven difficult because it subjects the IC chips to damage. On the other hand, techniques exist for bonding fully-fabricated semiconductor devices to each other. However, these leave the substrates of each device in place. This subjects the bonds to adverse mechanical stresses that may affect the devices adversely. In the case of GaAs/AlGaAs multiple quantum well (MQW) modulators, the substrates are GaAs which are opaque to the operating wavelength of the GaAS/AlGaAs modulators, and hence require removal for operation. Nevertheless, it is very difficult to place and bond GaAs/AlGaAs multiple quantum well (MQW) modulators, if they have had their substrates removed, onto silicon IC chips.
Prior techniques for bonding fully-fabricated semiconductor devices to each other, and in particular multiple quantum well (MQW) modulators to silicon IC chips, suffer the disadvantages of mechanical stress, opacity, or cumbersome handling.
An object of the invention is to overcome these disadvantages.
Another object of the invention is to improve bonding of semiconductor devices with each other.
Another object of the invention is to improve bonding of photonic elements with electronic elements. | {
"pile_set_name": "USPTO Backgrounds"
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Electrically erasable programmable read only memory (EEPROM) structures are commonly used in integrated circuits for non-volatile data storage. EEPROM device structures commonly include a polysilicon floating gate formed over a tunnel dielectric, which is formed over a semiconductor substrate, to store charge. As device dimensions and power supply voltages decrease, the thickness of the tunnel dielectric cannot correspondingly decrease in order to prevent data retention failures. An EEPROM device using isolated silicon nanocrystals or nanoclusters as a replacement to the floating gate does not have the same vulnerability to isolated defects in the tunnel dielectric and thus, permits scaling of the tunnel dielectric and the operating voltage without compromising data retention.
In order to have a significant memory effect as measured by the threshold voltage shift of the EEPROM device, it is necessary to have a high density of silicon nanoclusters of approximately 1E12 nanoclusters per cm2. One method to achieve such a density of nanoclusters is to fabricate the nanoclusters using chemical vapor deposition (CVD) using disilane (Si2H6). However, the resulting nanoclusters vary in size distribution, which decreases reliability of the EEPROM devices. To improve reliability, a method to form nanoclusters with narrow size distributions at desired densities is needed.
Nanocrystal memories typically have a data storage retention time that is specified as typically no greater than ten years in time. However, there are numerous commercial products which use non-volatile memories that must have a longer retention time. Further scaling of memory devices requires a reduction in operation voltages and program and erase times.
Skilled artisans appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help improve the understanding of the embodiments of the present invention. | {
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Oxide gel based materials (e.g. silica gels) are widely used as catalyst supports for the polymerization of olefins. Silica gel has been used as a support per se or has been used in the form of a cogel or tergel with metals such as chromium and titanium.
Oxide gels (including cogels and tergels) are most often commercially prepared by a gelation from an aqueous system to form a porous hydrogel containing water in its pores. For use in polymerization processes, it is generally necessary to remove the water from the hydrogel. Unfortunately, simple drying cannot be used to remove the water since shrinkage of the desired porosity will occur.
In order to overcome the water removal problem, several techniques have been attempted in the prior art. Many of these methods are discussed in numerous patents assigned to Phillips Petroleum Company. U.S. Pat. Nos. 3,900,457, 4,081,407, 4,152,503 and 4,436,883 discuss the use of azeotropic distillation techniques for removal of water from the gel while avoiding pore collapse. U.S. Pat. No. 4,169,926 discusses a process where the gel is given a one time impregnation with certain organic liquids followed by drying.
While azeotropic distillation has proven to be effective, there are various disadvantages associated with the known processes. For example, certain preferred organic solvents such as those described in U.S. Pat. No. 3,900,457 take a long time to achieve the desired distillation owing to their limited miscibility with water. On the other hand, the organic solvents used in U.S. Pat. Nos. 4,081,407 and 4,152,503have resulted in more rapid water removal, but these various organic distillation liquids are relatively expensive in the quantities needed for commercial production. For Ti--Cr--SiO.sub.2 systems, these azeotropic processes can result in excessively high melt index capability.
These problems have led to use of alternative techniques such as those described in U.S. Pat. Nos. 4,169,926 and 4,436,883. While these other techniques may be more economical than azeotropic distillation, the resulting catalyst is generally not as good can be obtained by azeotropic techniques.
Accordingly, there is a need for an economical azeotropic distillation technique for use in production of silica gel based materials for catalyst applications. | {
"pile_set_name": "USPTO Backgrounds"
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A redundantly repairable array device is one which contains a main array and spare elements, often built adjacent the main array, which can be substituted for defective original elements of the main array in order to repair it. A redundant memory device may, for example, be a rectangular array of memory cells each of whose elements, i.e., rows and columns, comprises a plurality of individual memory cells, and which also has several redundant rows and redundant columns of cells. If the main array contains a faulty cell, it can be repaired by replacing either the entire row or entire column which contain the faulty cell, with a redundant element. If several cells are faulty one or several redundant elements may be employed, and the choice of whether to repair a particular cell by replacing the row of which it is a member or the column of which it is a member, can be more difficult. Incorrect choice may result in exhaustion of the redundant elements before a complete repair plan has been devised and the consequent rejection of an array for which a correct choice would have enabled a complete repair. After assignments of redundant elements have been made to cover all of the faults, the memory array may be sent to a laser "trimmer" for execution of the repair plan. In some cases it may be impossible to devise a plan that would enable repair of all of the faults with the limited number of redundant elements that are available.
The use of redundant elements for repair can increase the yields of array products significantly. Bubble memory manufacturers have used the redundancy technique extensively, and it has become popular also in the manufacture of relatively high bit density devices such as 256K DRAMs.
Present techniques for assignment of redundant elements to faulty memory locations include a two step process. The first step would be to ascertain which elements of a memory array are faulty. The information obtained during this procedure along with information of the redundant rows and columns available would then be collated by means of an algorithm for computation of a replacement scheme which would result in an assignment of the redundant rows and columns in such a way to replace all of the defective memory locations, if such a replacement is then determined to be feasible.
The redundancy technique has some offsetting disadvantages, however, two of which are increased cost of testing the products and reduced throughput (average productivity). These disadvantages are related to the hardware and time that are required to determine whether the arrays are reparable and, if they are, what the repair instructions should be. Conventional array testers can require seconds or minutes to determine and specify the instructions that are required to make a repair. The time required to prepare repair instructions for an array has ordinarily been in addition to the time required to test it to identify its faulty cells. The result is small throughput, as few arrays can be tested and analyzed per hour. The invention is a cost-effective method and apparatus for alleviating these problems. | {
"pile_set_name": "USPTO Backgrounds"
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The present invention relates generally to a system for detecting a displacement between an objective lens and a surface to be measured and more particularly, to the system using the optical astigmatic method.
The non-contact measuring method such as the optical astigmatic method, critical angle detecting method, or knife edge method is conventionally known, which serves to measure a displacement between the objective lens and the surface to be measured, or a shape and roughness of the surface. A displacement detecting system using such measuring method includes, for example, a non-contact surface roughness tester which uses an absolute level of a focus error signal to detect a displacement between the objective lens and the surface to be measured, and a focusing-type non-contact displacement detecting system which includes a drive arranged to the objective lens so as to make the latter follow the surface through feedback control of a focus error signal, detecting a displacement between the two through the drive.
FIG. 9 shows a constitution of the displacement detecting system disclosed in JP-A 4-366711. This system is a focusing-type non-contact detecting system with a scale. Referring to FIG. 9, an optical detector, designated generally by reference numeral 1, is arranged to detect through light reflected by a surface 6 to be measured a deviation of a distance between an objective lens 5 and the surface 6 from a focal length. An actuator 16 is arranged to move the objective lens 5 in the direction of an optical axis 21 in response to an output of a light receiving element 7 of the optical detector 1 so that the distance between the objective lens 5 and the surface 6 is equal to the focal length. A linear scale 20 is disposed on an axis 22 which is in line with the optical axis 21 of the objective lens 5, and integrally mounted to the actuator 16 so as to move together with the objective lens 5. The optical detector 1 comprises a laser diode 2, a beam splitter 3, and a mirror 4 in addition to the light receiving element 7.
The conventional displacement detecting system operates as follows: The optical detector 1 detects a deviation of the distance between the objective lens 5 and the surface 6 from the focal length through light reflected by the surface 6, and the actuator 16 moves the objective lens 5 in the direction of the optical axis 21 so that the distance between the objective lens 5 and the surface 6 is equal to the focal length in response to an output of the light receiving element 7 of the optical detector 1. The linear scale 20, disposed on the axis 22 which is in line with the optical axis 21 of the objective lens 5 and integrally mounted to the actuator 16, is moved together with the objective lens 5 in accordance with a displacement of the surface 6. By this, a displacement of the surface 6 can be detected as a displacement of the linear scale 20.
With the conventional displacement detecting system, however, the optical detector 1 needs at least the laser diode 2, beam splitter 3, mirror 4, and light receiving element 7, and is constructed by the combination of the above parts, resulting in a complicated constitution and increased size of the system. Further, due to the need of fine adjustment, the system has a weak point for a dislocation and vibration, resulting in unsuitable mass production.
Further, when the drive is arranged to the objective lens 5 so as to be variable with respect to the surface 6, a collimator lens is needed in addition to the objective lens 5, which may produce a dislocation upon mounting, resulting in a potential occurrence of an error factor.
Furthermore, due to lengthened optical path of the optical detector 1 upon position detection, the component parts of the optical detector 1 undergoes an influence of thermal expansion, etc. by temperature variation, resulting in a difficult measurement of the displacement amount of the surface 6 with accuracy higher than on the order of 1/100 [.mu.m].
It is, therefore, an object of the present invention to provide a system for detecting a displacement between an objective lens and a surface to be measured with high accuracy and a reduced size. | {
"pile_set_name": "USPTO Backgrounds"
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The following references to and descriptions of prior proposals or products are not intended to be and are not to be construed as statements or admissions of common general knowledge in the art. In particular, the following prior art discussion does not relate to what is commonly or well known by the person skilled in the art, but may assist in the understanding of the inventive step of the present invention, of which the identification of pertinent prior proposals is but one part.
In many parts of the world, there is a high level of concern over excess energy usage. There have been many proposals aimed at saving energy, at both international and national levels.
In the area of inventions which may effect energy savings, reference is made to International Patent Application No WO 2005/111766 and International Patent Application No WO 2008/064410. Each of these patent specifications is incorporated herein by reference and both are referred to below as the International Applications.
The International Applications disclose inventions where electrical devices are connected to a single mains supply electrical outlet, and the current flow through and voltage across at least one of the electrical devices is monitored in order to determine a functional state of that device. Depending on the nature of the functional state of the device and the nature of the other electrical devices, the supply of power to any or all of the other electrical devices can be shut off, so that not all electrical devices are powered in situations where power to them is unnecessary.
The present invention is predicated upon the concept that energy saving capability of such energy saving devices as those in the International Applications may be enhanced by monitoring and, in some embodiments, by networking a plurality of such energy saving devices.
Although energy saving devices such as those in the International Applications may autonomously maximise energy savings at their individual level, it is believed that the addition of networking capability can provide advantages not available before now. | {
"pile_set_name": "USPTO Backgrounds"
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The following disclosure is based on German Patent Application No. 100 24 986.8, filed on May 19, 2000, which is incorporated into this application by reference.
The present invention relates to an electronic weighing sensor having a digital signal processing unit, which includes at least one filter with a low-pass characteristic. By means of the filter, the direct-current component of the output signal of the weighing sensor is determined and the weighing result is derived therefrom.
Weighing sensors of this type are generally known in the art. The low-pass filter is used to suppress the alternating-current components, which are superimposed on the output signal of the weighing sensor when the installation site of the weighing sensor is subject to shocks or vibrations. Generally, despite this measure, the measuring results of weighing sensors and scales that are based on weighing sensors are clearly more difficult to reproduce if the installation site is subject to shocks or vibrations than if the installation site is steady.
To improve the performance of weighing sensors and scales at unsteady installation sites, it is known, for instance from U.S. Pat. No. 5,789,713, to provide a second, weighing sensor having a constant load whose output signal is used to derive a correction signal for the actual (measuring) weighing sensor. The mechanical and electronic complexity caused by this second weighing sensor is considerable, however.
Similarly, German laid-open document DE 40 01 614 A1 teaches the provision of at least one acceleration sensor instead of a second, constantly-loaded weighing sensor, which supplies a correction signal for influencing the measuring result. In both cases, however, the correction signal must be subtracted from the signal of the (measuring) weighing sensor in such manner that the phases of both signals are properly taken into account so that the interference can be corrected. This in-phase subtraction, however, can be achieved within only a limited frequency band. At the upper end of this frequency band, the phase shifts are more and more increased and differ between the measuring path and the correction path. This results, in the worst case, in an additionxe2x80x94and thus an amplificationxe2x80x94of the signals rather than a subtractionxe2x80x94and thus a cancellation. This is particularly true for acceleration sensors that are employed as correction generators, since the mechanically very differently structured system of the acceleration sensor has eigenfrequencies that are very different from those of the weighing sensor.
It is one object of the present invention to improve the performance of a weighing sensor in case of shocks and vibrations in the installation site without requiring a second weighing sensor or an acceleration sensor for correction purposes. Therein, problems due to phase shifts at the edge of the frequency range are to be avoided.
According to one formulation of the invention, this and other objects are achieved by providing a method for deriving a weighing result, in which a direct-current component of an output signal of an electronic weighing sensor is determined by means of a low-pass filter that is arranged in a digital processing unit. In addition, a further signal is determined by the digital processing unit that is dependent on an amplitude of vibrations of the electronic weighing sensor. The direct-current component is changed by electronic components in accordance with a magnitude of the further signal that is dependent on the amplitude of the vibrations.
This approach is based on the finding by the inventors that the poor reproducibility of weighing sensors at unsteady installation sites is not only caused by inadequate suppression of the alternating-current component in the output signal of the weighing sensor. Rather, a significant contribution to the poor reproducibility is due to the fact that the direct-current component in the output signal of the weighing sensor is influenced as a function of the amplitude and the frequency range of the alternating-current component. Thus, stronger suppression of the alternating-current component in the output signal of the weighing sensor alone does not sufficiently improve the performance of a weighing sensor that is subject to vibrations. In addition to that, a correction of the direct-current component must be carried out, as proposed by the present invention.
The causes for this influence on the direct-current component may be illustrated by three examples:
In the case of weighing sensors that have a non-linear characteristicxe2x80x94as shown in FIG. 1 in exaggerated formxe2x80x94and that are installed at a steady installation site, the load m1 is associated with the output signal corresponding to point A. In an unsteady site, however, the output signal fluctuates between the extreme points B and C along the non-linear characteristic B-A-C. Depending on the amplitude spectrum of the vibrations, the direct-current component of this output signal is located somewhere between points A and D. As a result, even if the alternating-current component in the output signal is completely suppressed, the direct-current component changes due to the non-linearity of the characteristic curve. This change is suppressed by the electronic components according to the present invention.
In the case of weighing sensors that operate based on the principle of electromagnetic force compensation, as illustrated schematically in FIG. 2, a coil 2, through which a current flows, is located in the magnetic field of a permanent magnet 1. The current flowing through the coil 2 is regulated by a position indicator 3 and by a downstream regulation amplifier 4 in such a manner that the electromagnetically generated force is precisely equal to force F to be measured. The magnitude of this current is measured at a measurement resistor 5 and is supplied to an output 6 as an output signal of the weighing sensor. As is well known, the quantitative relation between the magnetic field B, the current I and the generated force F is:
F≈Bxc2x7Ixe2x80x83xe2x80x83(1)
To achieve optimal efficiency, the coil 2 is positioned in such a way that it is located at the point of the maximum magnetic field of the permanent magnet 1. If the coil 2 is caused to oscillate due to vibrations in the base, the coil 2 moves sometimes outside the magnetic field maximum and into a region with a lower magnetic field. On temporal average, the magnetic field B in equation (1) is thus lower than in a steady installation site where coil 2 is always located within the magnetic field maximum. Consequently, according to equation (1), a greater average current I is required to generate the same force F. Thus, in this example too, the direct-current component changes when there are shocks/vibrations so that, in addition to suppressing the alternating-current component, the direct-current component must also be corrected in order to obtain a stable and exact result.
If the characteristic curve of the position indicator 3 in the above-described weighing sensor according to FIG. 2 is asymmetrically non-linear, the average transient position is shifted when there are vibrations, as illustrated above by means of FIG. 1. On the one hand, this change in the average transient position causes a change in the effective magnetic field at the position of the coil, as shown in the second example. On the other hand, a slight deflection in the parallel guidance 7 of the scale tray 8 and coil 2 is caused by this change. If the parallel guidance 7 is realized by spring-type hinges, this causes a vertical spring force, which changes the direct-current component in the weighing signal.
Other causes, which are not further described here, may also distort the direct-current component in the weighing signal, e.g., non-linear amplifiers or non-linear transmission levers. Of course, all the described effects are small and, therefore, have consequences at high resolutions of the weighing sensor only.
Advantageous embodiments are set forth in the dependent claims.
The use of a high-pass filter for determining the vibration-dependent alternating-current components in the output signal of a weighing sensor and the control of a display element or a print lock (in case the alternating-current component exceeds a predefined limit value) is generally known in the art of scale technology. Such structures and methods are described, for instance, in German Patent DE 23 23 200. In the prior art, however, no influence is effected on the direct-current component of the output signal of the weighing sensor. | {
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This invention relates to a signal supplying device for supplying signals to an operating panel for a passenger provided in each of plural seats of a moving vehicle, such as an aircraft or a train.
In a moving vehicle, such as an aircraft or train, it is possible for the passenger in each seat to select a desired channel from several choices to hear e.g., audio signals over a headphone or an earphone.
Among the several channels, there are channels dedicated to programs for which a fee is charged. These programs are offered by a system in which an opening in a headphone jack or an air tube fitted on the seat is configured so as not to be engaged by a plug and the crew in charge hands over an adapter to a passenger who has paid the fee permitting the headphone to be inserted into the opening only by the passenger who has paid the fee.
If the program is offered in a manner described above, the adapter is likely to be lost. On the other hand, the operating cost is raised because a headphone different from that for an ordinary program has to be provided for the program for which a fee is charged.
It may also be contemplated to provide a card reader e.g., a credit card reader for each seat to permit the program to be paid for by credit card. Although this system saves the labor of the crew to collect the fee and there is no risk of loss of the adapter, the device and the system become complex thus raising the cost.
It is therefore an object of the present invention to provide a signal supplying and receiving system in which the dedicated adapter or the headphone as well as a complex device may be eliminated to realize low cost.
According to the present invention, there is provided a signal supplying/receiving system having an operating unit for a passenger provided in each of plural seats for passengers within a moving [vehicle], and a supplying device for supplying signals to said operating unit. The signal supplying/receiving system includes selecting means for selecting an optional one of plural channels supplied from the supplying device, and control means for controlling the selection means for inhibiting selection of one or more channels among the plural channels. The control means also causes inhibition of selection of the one or more channels to be canceled responsive to a remote control signal received by a remote control signal receiving unit.
Preferably, the remote control signal includes a code specifying the cancellation of inhibition of selection of the one or more channels and an ID signal for identifying the seat.
Preferably, the control means causes the inhibition of selection of the one or more channels by the selection means of an operating unit for the passenger when a seat specified by the ID signal included in the remote control actuating signal is coincident with the operating unit for the passenger associated with the control unit.
Preferably, the remote control signal is an infra-red light beam emitted by a remote controller.
Preferably, the remote control signal receiving unit is provided for each of groups of seats made up of a plurality of the seats.
Preferably, an actuating panel is further provided in the signal supplying/receiving system. The selection means selects a channel selected by a passenger via the actuating panel.
Preferably, the signals supplied from the supplying device are audio signals. | {
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The closed loop bandwidth for a conventional current feedback operational amplifier is given by: EQU B.sub.W =[C.sub.c (R.sub.2 +G R.sub.in)].sup.-1 (Eq. I)
Here, C.sub.c is the compensation capacitance at the high gain node of the operational amplifier, R.sub.2 is the feedback resistor, and G is the closed loop voltage gain for the amplifier, which is equal to (1+R.sub.2 /R.sub.1), where R.sub.1 is the gain-setting resistor between the inverting input of the operational amplifier and ground.
For an ideal current feedback operational amplifier, the input impedance, R.sub.in, is zero, and consequently, the closed loop bandwidth of the circuit is independent of the amplifier gain. In conventional current feedback operational amplifiers, however, R.sub.in is non-zero, its magnitude being determined by the intrinsic emitter resistance of the transistors which form the inverting input of the amplifier. This emitter resistance depends on the bias current in the transistor, and for a bipolar transistor it is typically on the order 26 ohms per 1 mA of emitter current.
The feedback resistor, R.sub.2, is typically on the order of a few thousand ohms, and as long as the product, G R.sub.in, is small relative to R.sub.2, the closed loop bandwidth of the amplifier will be virtually independent of gain. However, since R.sub.in is non-zero, G R.sub.in will be comparable R.sub.2 for sufficiently high gains, causing a roll off in B.sub.W.
The transfer function of a closed loop current-feedback operational amplifier and the DC closed-loop gain accuracy, A.sub.c also roll off for large gains. The transfer function is given by: EQU V.sub.out /V.sub.IN =G Z.sub.t /(Z.sub.t +R.sub.2 +G R.sub.in),(Eq. II)
where Z.sub.t is the open loop transimpedance gain. As with B.sub.W, the transfer function will begin to decrease as the product G R.sub.in becomes comparable to R.sub.2 at high gains. Similarly, the DC closed-loop gain is given by: EQU A.sub.c =G Z.sub.o /(Z.sub.o +R.sub.2 +G R.sub.in) , (Eq. III)
where Z.sub.o is the DC open loop transimpedance gain. As with B.sub.W and the transfer function, the gain accuracy falls off for large gains due to its inverse dependence on the factor G R.sub.in.
In addition to these problems, the inverse dependence of R.sub.in on the transistor bias current introduces non-linearities into the circuit response for large input signals. While the effect of such non-linearities can be partially offset by operating the amplifier at higher bias currents, this approach increases power dissipation and noise in the amplifier circuit. | {
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The present invention relates to the art of packaging semiconductor devices, and more particularly, to an improved silver-glass paste which is deposited in a viscous state between a die and a ceramic substrate and then fired to form a secure bond therebetween.
Silver-glass pastes have been used for a number of years to attach silicon die to ceramic substrates. U.S. Pat. Nos. 3,497,774 of Hornberger et al.; 4,101,767 of Dietz et al.; and 4,761,224 of Husson et al. disclose examples of such pastes. Typically they include a high lead glass frit, silver particles and a suitable organic vehicle. This vehicle is typically made of a resin and a solvent. During an initial drying phase the liquid vehicle evaporates. Upon firing, the remaining organic vehicle, i.e. the resin, decomposes, the glass softens to wet the ceramic and the silver flake sinters together.
The principal reason for using a resin in the organic vehicle of a die attach paste is for solvent spread attenuation. If only a solvent were used it would quickly spread across the surface of the ceramic substrate carrying glass and silver particles with it. The resin provides a suitable entrainment mechanism that retards such solvent spread.
The traditional vehicle system used in silver-glass die attach pastes consists of one or more high boiling organic solvents and a resin. The combined organics are required to volatilize and/or decompose cleanly during the curing of the product to leave the silver-glass composite free of carbonized residues. The clean organic burnout requirement has essentially restricted the polymers used as resins in this system to the following categories: (1) polyalkyl methacrylates; (2) nitrocellulose (with nitrogen content.gtoreq.12.0%); (3) polyisobutylenes; and (4) polypropylene gylcols. Polymer's of alpha-methylstyrene represent a fifth potentially useful class of resins that upon thermolysis yield completely volatile decomposition products. Their use, however, would be restricted to cure under non-oxidizing conditions.
Resins have been shown to impart the following beneficial properties in order of decreasing importance: (1) reduction in solvent bleed from the perimeter of the uncured paste fillet; (2) reduction in the rate of settling of the paste solids; (3) facilitation of the dispersion and wetting of the glass and silver; and (4) provision of green strength to paste in the dried state.
Practical considerations have limited the options for resin selection. The polyalkyl methacrylates have been shown to possess the best blend of properties for use in die attach application. The preferred methacrylate polymers include those generated from esters of the lower alcohols (i.e. where the alkyl is methyl, ethyl, propyl or butyl).
Use of the commercially available polyalkyl methacrylates has proven to be problematic. It has been demonstrated that whenever sufficient methacrylate resin was used to curb solvent spread that the resulting pastes had excessive tailing when dispensed from automatic die bond equipment. Tailing or stringiness has a major negative impact on the application of these pastes, especially when they are dispensed from equipment configured with a starfish nozzle. The downsides from this problem included a reduction of product throughput and/or an increased yield loss neither of which could be tolerated by paste users.
It is well known that the molecular weight of the polymer used has a pronounced effect on solvent spread. Generally the higher the molecular weight the lower the degree of solvent spread for any given weight percent of resin dissolved in the vehicle solvent. Presumably, the dispensability of the paste could be improved by incorporation of the minimum amount of high molecular weight resin capable of solvent spread attenuation. Unfortunately, this approach is thwarted by the simultaneous increase in stringiness of the polyalkyl methacrylates as molecular weight is increased. A paste formulation based on the commercial methacrylate resins must of necessity represent a compromise between low solvent spread and acceptable dispensing properties which cannot be simultaneously optimized. | {
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1. Field of the Invention
The present invention relates to a base unit for use in a disk drive apparatus.
2. Description of the Related Art
Disk drive apparatuses, such as, for example, hard disk drive (HDD) apparatuses, are often arranged to rotate disks at high speeds. In such an apparatus, each disk receives resistance caused by a gas enclosed in the apparatus, and this may cause a vibration of the disk and an error in reading or writing, an increase in a power consumption of a motor, or other problems. In particular, in recent years, the storage capacity of HDD apparatuses or the like has been increasing, and the number of disks has been increasing, and it has become important to take measures against the above problems.
Accordingly, instead of air, a gas (which may be hereinafter referred to as a low-density gas) having a density lower than that of air is sealed in a known disk drive apparatus to reduce the aforementioned resistance during rotation of the disk. As this low-density gas, helium or the like is used, for example.
In such a disk drive apparatus, it is important to improve the sealing in of the low-density gas. JP-A 2008-171482, for example, discloses a disk drive apparatus including a base and a cover, and having a low-density gas sealed in a housing space defined by the base and the cover fixed to each other.
In this disk drive apparatus, a feedthrough, which is a connector of one type, is joined to the base through a solder so as to close an opening defined in the base to prevent the low-density gas from leaking out of the base through the opening.
However, as noted in JP-A 2008-171482, a flange of the feedthrough and the base have different coefficients of thermal expansion, and therefore, an application of a stress to a solder joint with low stress resistance might cause a crack in the solder joint, resulting in a failure to sufficiently seal in the low-density gas.
It is thus conceivable to use an adhesive which is more resistant to heat shock than the solder and is also inexpensive as a material for joining the base and the connector to each other. | {
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A voice encoder is good at encoding voice-type audio signals under mid-to-low bit rates, while has a poor effect on encoding music-type audio signals. An audio encoder is applicable to encoding of the voice-type and music-type audio signals under a high bit rate, but has an unsatisfactory effect on encoding the voice-type audio signals under the mid-to-low bit rates. In order to achieve a satisfactory encoding effect on audio signals mixed by voice and audio under the mid-to-low bit rates, an encoding process that is applicable to the voice/audio encoder under the mid-to-low bit rates mainly includes: first judging a type of an audio signal by using a signal classification module, and then selecting a corresponding encoding method according to the judged type of the audio signal, and selecting a voice encoder for the voice-type audio signal, and selecting an audio encoder for the music-type audio signal.
In the prior art, a method for judging the type of the audio signal mainly includes:
1. Divide an input signal into a series of overlapping frames by using a window function.
2. Calculate a spectral coefficient of each frame by using Fast Fourier Transform (FFT).
3. Calculate characteristic parameters in five aspects for each segment according to the spectral coefficient of each frame, namely, harmony, noise, tail, drag out and rhythm.
4. Divide the audio signal into six types based on values of the characteristic parameters, including a voice type, a music type, a noise type, a short segment, a segment to be determined, and a short segment to be determined.
During implementation of judging the type of the audio signal, the inventor finds that the prior art at least has the following problems: In the method, characteristic parameters of multiple aspects need to be calculated during a classification process; audio signal classification is complex, which result in high complexity of the classification. | {
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This invention relates to a system for applying an ultrasonic probe to the surface of a living body to measure the reflected ultrasonic waves therefrom and thereby obtain an ultrasonic tomographic image, or determine a velocity of flow of the blood, and more particularly to a measurement apparatus using a measurement signal from a portion, which moves periodically due to the cardiac motion, of a living body.
In a diagnosis apparatus, it is greatly necessary to obtain information from a moving region of interest. Regarding, for example the heart, various diagnosis information of a high accuracy cannot be obtained without taking the influence of the cardiac motion into consideration. In order to meet these requirements, a measurement method utilizing an electrocardiogram as a synchronizing signal, i.e. the periodicity of a cardiac motion is widely used.
For example, the thesis entitled "Gated Cardiac Computed Tomography with a Motion Phantom" in the "Radiograph", Vol. 134, pp 213-217, points out that a clear stop motion cardiac image can be obtained by repeatedly collecting the special-phase data alone in a cardiac cycle in the X-ray computed tomography, and thereby reconstructing the image.
In the ultrasonic radiography, the real time imaging is required, and repeatedly collecting special-phase data in a cardiac cycle so as to obtain one picture is contradictory to this purpose. In an apparatus for measuring a flow rate of the blood in the heart or a blood vessel in the vicinity of the heart, the moving speed of the heart or blood vessel is superposed on the flow rate of the blood, and an object to be measured goes out of the visual field of measurement due to the cardiac motion in some cases. | {
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1. Field of the Invention
The present invention relates to the cleaning of boat tanks, bilges, and holds; barges; mobile or land based tanks: cutting boxes or container; and related vessels (sometimes hereinafter referred to as "vessels") that have been contaminated with oil and gas well drilling fluids such as oil well drilling mud and the like or with hazardous waste. More particularly, the present invention relates to a method and apparatus for the cleaning (in a marine and land based environment) of vessels that have been contaminated with oil and gas well drilling fluids, wherein a recycling water recovery system reuses the same wash water over and over, while continuously concentrating solid material in a receiving barge after the wash water leaves the vessel being cleaned and carrying oil and gas well drilling fluid waste products therewith (including solid material), and wherein various treatment stations remove solid material, oil, and like pollutants from the wash water stream before it is recycled to clean the vessel a second time or to clean a second vessel or a third vessel, etc.
2. General Background
In the drilling of oil and gas wells, there are a number of fluids that are used in the drilling process. These fluids include for example drilling mud that contains heavy solids. This drilling mud becomes a pollutant when it is placed in a vessel that is used to transport drilling mud from land to oil and gas well and drilling production platforms located offshore.
Other oil and gas well drilling, completion and work over fluids include non-dispersed drilling mud, dispersed drilling mud, calcium treated drilling mud, drilling mud incorporating polymers, drilling muds prepared from fresh or brine water and sodium chloride, oil-based drilling mud and synthetic drilling mud. Other fluids used in the drilling of oil and gas wells include bactericides, calcium removers, corrosion inhibitors, defoamers, emulsifiers, filtrate reducers, flocculants, foaming agents, lost circulation materials, lubricants, pipe-freeing agents, shale control inhibitors, and surface active agents. A discussion of the various types of drilling, completion and workover fluids used in the oil and gas well drilling industry can be seen in the June 1994 issue of "World Oil".
Additionally, drilling fluids not used downhole in the drilling process or discarded hydrocarbon based waste fluids that have to be transported back to land are considered hazardous waste as defined by the United States Environmental Protection Agency.
The present method of cleaning such oil and gas well drilling fluids and hazardous waste from vessels is to simply wash the vessel while capturing the wash water in a barge. The wash water becomes contaminated with the oil and gas well drilling fluids and hazardous waste. The barge must then be shipped to a disposal site wherein the contaminated wash water is disposed of.
The disposal of a barge filled with wash water from such a vessel cleaning operation is an expensive and time consuming procedure. Each barge contains thousands of gallons of contaminated wash water and may have to be transported with a tug vessel to a disposal site. | {
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The present invention generally relates to apparatus and methods for metering product from a continuous stream into a product group and/or pack pattern, particularly to metering apparatus and methods not requiring windows between product in the continuous stream, more particularly to metering apparatus and methods which are versatile to meter a wide variety of product such as cans, plastic bottles, jars, cartons, bundles, or trays, and specifically to metering apparatus and methods where product is metered by moving a transfer device from underneath a product group positioned above a sweeping conveyor
In a typical packaging operation, product comes to a packaging machine in a continuous stream. It is necessary to separate product into groups so that they can be further processed such as being placed into a pack pattern and/or packed into a film overwrap or a corrugated wrap. U.S. Pat. Nos. 4,832,178 and 5,201,823 represent one manner of metering product utilizing pins which are inserted between product in lanes. However, it should be appreciated that such pin metering apparatus can only be utilized for product presenting windows between product. Additionally, such pin metering apparatus includes pins, rails, and supports between each lane of product which are multiple, high wear, moveable components and are very difficult and expensive to change over between different products. Other metering designs which control product from the side or top also require many parts, are complex, and are difficult to adjust.
Thus, a need continues to exist for apparatus and methods for metering product which do not suffer from the deficiencies of prior metering apparatus, especially those of prior pin metering apparatus. In particular, such apparatus and methods should be versatile enough to meter a range of product sizes and shapes including product which does not have windows between abutting product and can be changed over between different product sizes and shapes with minimum effort or expense, which is relatively low wear and maintenance, and which is relatively trouble free. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The present invention relates generally to reactions which are catalyzed by heterogeneous catalysts. More particularly the invention relates to the reaction of normally gaseous reactants in the presence of a heterogeneous catalyst. Most particularly the invention relates to the use of an inert component in a catalytic distillation column wherein the inert component is boiling and condensing.
2. Related Art
Over the years there have developed many methods of carrying out reactions in the presence of a solid heterogeneous catalyst. The most commonly used is probably the fixed bed downflow or trickle bed reactor. Also used is the upflow reactor which may have an ebullating bed if the flow rate is high enough. When the catalyst is fine and the reactants are gaseous a common method has been the fluidized bed. Similar to the fluidized bed is the slurry reactor wherein the solid catalyst is carried in one or more reactant streams. Finally there has arisen the reaction distillation column wherein the catalyst is disposed in a distillation column in a suitable form to act as a distillation structure. The final method has additional advantages in that the reaction products are separated from the reactants almost immediately upon formation by fractional distillation. This is particularly used in otherwise equilibrium limited reactions.
The use of catalytic distillation has been traditionally limited by the fact that one of the reactants must be a boiling liquid at the conditions inside the reactor. In the earlier catalytic distillation processes both reactants were fed to the reactor as liquids. More recently, U.S. Pat. No. 5,087,780 has shown that the catalytic distillation method is useful in a process wherein hydrogen is a reaction component. | {
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Error correction coding techniques can be used to reduce errors introduced during digital data transmission or storage. Prior to transmission, for example, each piece of data, such as a 16-bit word, can be encoded to incorporate additional information so that upon receipt, the data can be recovered even when errors are introduced during transit between transmitter and receiver.
In addition, two or more coding techniques can be combined to create more powerful encoding schemes, such as product encoding scheme. Product code can act on a data matrix that can be arranged from a data sequence. The data matrix can include a first dimension and a second dimension. Product code can encode vectors of the first dimension to incorporate additional information, and then encode vectors of the second dimension to further incorporate additional information. | {
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1. Field of the Invention
The present invention relates to an image forming apparatus that scans light irradiated on a photosensitive member while rotating the photosensitive member, thereby forming an image on the photosensitive member.
2. Description of the Related Art
In recent years, electrophotographic printers have been increasing in performance, and techniques for realizing improvements in responsiveness in printing, print speed, and print image quality, and low cost.
Examples of indexes for evaluating the responsiveness include FPOT (First Print Out Time) and FCOT (First Copy Out Time) as the time period between user's print instruction and the completion of output a first recording medium with an image formed thereon. FPOT and FCOT are desired to be a few seconds or less.
By the way, a thickness of a photosensitive layer (hereinafter referred to as the “film thickness”) of a photosensitive drum in electrophotographic printers cannot be uniform due to the limits of production accuracy. Moreover, a surface of the photosensitive drum wears because the photosensitive drum comes into contact with a recording medium, an intermediate transfer member, or a cleaning member during the formation of an image. At this time, the wear amount differs at individual positions of the photosensitive drum, and hence the unevenness of the film thickness is further promoted. In a case where such a photosensitive drum is charged and exposed to light, potential characteristics of the surface of the photosensitive drum cannot be uniform. For this reason, there are variations in an image density of an output image. Therefore, to correct for variations in the image density of an output image resulting from nonuniform potential characteristics of the surface of the photosensitive drum and improve image quality, a technique to correct for variations in the potential characteristics of the surface of the photosensitive drum has been developed. As examples of such a technique, those disclosed in Japanese Laid-Open Patent Publication (Kokai) No. S63-49779, Japanese Laid-Open Patent Publication (Kokai) No. 2004-223716, Japanese Laid-Open Patent Publication (Kokai) No. 2007-187829, and Japanese Laid-Open Patent Publication (Kokai) No. 2007-34233 are known. These prior arts are a technique to correct for variations in the potential characteristics of the photosensitive drum by adjusting a laser light exposure amount according to a position exposed to light when an exposure unit exposes the photosensitive drum to light. This technique have realized an improvement in print quality, resulting in an improvement in allowable variation level, and a decrease in the production cost of the photosensitive drum which is highly-durable and long-lived and allows variations in the potential characteristics.
FIG. 6 is a diagram schematically showing an arrangement of an optical writing unit in an image forming apparatus that corrects for variations in the potential characteristics of the surface of a photosensitive drum. The image forming apparatus is a one-photosensitive drum four-beam laser simultaneous scanning electrophotographic printer. For the simplification of explanation, units for forming an image on a paper medium, such as a charging unit, a developing unit, a transfer unit, and a fixing unit associated with a general electrophotographic process are omitted from the figure.
The image forming apparatus has a multi-beam laser optical writing unit 1100, a system control unit 1140, an image data process unit 1150, a photosensitive drum 1130, and so on. The system control unit 1140 controls the overall operation of the apparatus, and is comprised of a CPU, a ROM, a RAM, a user interface (not shown) for controlling devices, and so on.
The image data process unit 1150 is comprised of an ASIC, and operates while communicating information with the system control unit 1140 by register access from the CPU of the system control unit 1140. A drum drive unit 1136 that drives the photosensitive drum 1130 to rotate is provided on a side of the photosensitive drum 1130.
FIG. 7 is a timing chart showing operations of the units when the photosensitive drum starts rotating in the image forming apparatus. The timing chart shows a photosensitive drum drive state 1201, a photosensitive drum potential characteristic variation correcting process valid/invalid state 1202, and a rotation reference position signal 1122. The rotation reference position signal 1122 is obtained by a rotation reference position sensor 1120 and a rotation position mark 1121. States a to e in the figure correspond to determinations about control states by the system control unit 1140 and state transitions responsive to control instructions.
FIGS. 8A and 82 are flowcharts showing procedures of an image forming operation and procedures of a potential characteristic variation correcting operation. In the figure, FIG. 8A shows the operation of the CPU in the system control unit 1140, and FIG. 8B shows the operation of a potential characteristic correction unit 1161 in the image data process unit 1150 (ASIC). In the figure, broken lines indicate transmission of information via input/output signals to and from the devices.
Referring to FIGS. 6, 7, 8A, and 8B, a description will be given of the operation of the image forming apparatus. The system control unit 1140 brings the image forming apparatus into an image formation stopped-and-drum stopped state as an initial state (step S101). This state is represented by the drive state a in FIG. 7. On the other hand, the potential characteristic correction unit 1161 lies in a state of not corrected for variations as an initial state. Namely, the potential characteristic correction unit 1161 is waiting in the variation correcting process invalid state d in FIG. 7.
The system control unit 1140 waits for an instruction to start image formation (step S102). Upon receiving the instruction to start image formation, the system control unit 1140 instructs the drum motor drive unit 1136 and a polygon mirror motor drive unit 1103a to start operating, thus starting a preparation for image formation (step S103). In the preparation for image formation, the drum drive unit 1136 starts driving the photosensitive drum 130 according to a rotation instruction signal 1141 given to the drum drive unit 1136. At the same time, the polygon mirror motor drive unit 1103a starts rotating a polygon mirror 1103 at constant speed according to a rotation instruction signal 1142 for scanning laser light. At this time, the drive state 1201 of the photosensitive drum 1130 is the drive state b.
The system control unit 1140 waits until a predetermined waiting time period has elapsed after the start of the motors (step S104). When the predetermined waiting time period has elapsed, the drive state 1201 of the photosensitive drum 1130 changes to the drive state c in which the photosensitive drum 1130 rotates at stable constant speed required for image formation.
The system control unit 1140 confirms an input of the rotation reference position signal (drum reference signal) 1122 (step S105). In the drive state b in which the photosensitive drum 1130 starts rotating and the drive state c, the rotation reference position signal 1122 is generated each time the rotation position mark 1121 on the photosensitive drum 1130 passes the rotation reference position sensor 1120 of the photosensitive drum 1130.
After the drive state 1201 of the photosensitive drum 1130 changes to the drive state c in which the photosensitive drum 130 rotates at stable speed, the rotation speed of the polygon mirror 1103 stabilizes, and further, at the time when the rotation reference position signal 1122 is inputted, the system control unit 1140 instructs to correct for variations in potential characteristics (step S106). As a result, a register access instruction 1143 for the correction for variations in potential characteristics is generated, and the variation correcting process valid/invalid state 1202 changes to the valid state e.
The system control unit 1140 carries out the image forming operation (step S107). During the image forming operation, the image data process unit 1150 starts image data process in response to the register access instruction 1143 for image formation from the system control unit 1140.
When image data 1151 is inputted from an external personal computer (not shown), the image data 1151 is sent to a line buffer control unit 1152 and stored as data in line buffers 1153 corresponding in number to the number of multiple lasers. The stored data is read in parallel as data corresponding in number to the number of multiple lasers from the line buffers 1153 in timing with BD signals 1135, and sent to a photosensitive drum potential characteristic correction image process unit (multiplication unit) 1154.
Next, a description will be given of a flow of a photosensitive drum potential characteristic variation correction image process. After the photosensitive drum 1103 goes into the drive state c in which it rotates at stable speed, the potential characteristic correction unit 1161 carries out an address computation at the time when the rotation reference position signal 1122 is inputted (step S201). The address computation is carried out based on the BD signal 1135 indicative of a scanning start position generated by laser light incident on a laser light sensor for controlling a beam exposure start position in laser scanning, and counting using crystal oscillator clocks. As a result of the address computation, an appropriate address for taking out variation correction data is selected.
The potential characteristic correction unit (memory controller) 1161 selects and successively reads correction data from a nonvolatile memory (table memory) 1160 storing table data on variations in photosensitive drum potential characteristics (correction data) (step S202). The correction data is prepared in advance in the table memory 1160 in accordance with a photosensitive drum provided in the image forming apparatus.
The potential characteristic correction unit 1161 causes matching process units 1163 to successively carry out processes for matching the table data on variations in photosensitive drum potential characteristics transmitted via memory data buses 1162 to data that is to be multiplied with image data (step S203). Further, the potential characteristic correction unit 1161 successively transmits the variation correction data from the matching process unit 1163 to the multiplication unit 1154 (step S204). The multiplication unit 1154 multiplies the image data with the variation correction data. After that, the potential characteristic correction unit 1161 terminates the present operation.
In the above described way, after the drive state 1201 of the photosensitive drum 1103 goes into the drive state c in which it rotates at stable speed, at the time when the rotation reference position signal 1122 is inputted, an appropriate address for taking out variation correction data is selected based on the BD signal 1135 indicative of a scanning start position and counting using the crystal oscillator clocks. Thereafter, the potential characteristic correction unit 1161 goes into a state of correcting for variations in potential characteristics, and the variation correction process valid/invalid state 1202 goes into the valid state e.
The data having been subjected to the potential characteristic variation correcting process by a computation (multiplication) of the data from the line buffers 1153 and the variation correction data in the multiplication unit 1154 is transmitted to a laser Pulse Width Modulation Unit (PWMU) 1155, and made available for use in blinking a four-beam multi-laser semiconductor chip 1101 via a laser current drive unit 1106.
The laser light is gathered by a collimator lens 102 and then reflected/scanned by the polygon mirror 1103 to pass through an fθ lens 104. Further, the laser light follows a laser light path 1105 from the polygon mirror 1103 to the photosensitive drum 1130 and is scanned on the photosensitive drum 1130 along paths taken by scanning lines 1133 of exposure spots 1131 by the four-beam multi laser by rotation of the polygon mirror 1103. On the photosensitive drum 1130 thus charged, an electrostatic latent image is formed.
After the electrostatic latent image is formed, the image forming apparatus develops the electrostatic latent image with toner, transfers the image to a paper medium, fixes the image on the paper medium by heating and pressurizing, so that an image is formed.
When a time period required to form an image of a predetermined size has elapsed, the system control unit 1140 determines whether or not the image forming operation has been completed (step S108). When the image forming operation has been completed, the system control unit 1140 outputs the rotation instruction signal 1141 to stop the rotation of the photosensitive drum 1103 (step S109), and waits until the stop of the photosensitive drum 1130 is confirmed (step S110). Upon confirming the stop, that is, the completion of the deceleration, the system control unit 1140 terminates the present operation.
By carrying out the above described operation, the image forming apparatus draws a latent image on which the correction for variations in the potential characteristics of the photosensitive drum has been carried out, and the correction for variations in laser writing has been carried out.
However, there are problems as described below in improving the performance of the conventional image forming apparatus. When acceleration control for accelerating the photosensitive member is switched to constant-speed control, the formation of an image may not be started immediately depending on the position of the rotation position mark 1121 provided on the photosensitive drum relative to the rotation reference position sensor 1120. The correction for variations in the potential characteristics of the photosensitive drum is started in response to generation of the rotation reference position signal (drum reference signal) 1122. The rotation reference position signal 1122 is generated in response to the rotation position mark 1121 provided on the photosensitive drum passing the rotation reference position sensor 1120, but the formation of an image cannot be started unless the rotation reference position signal 1122 is generated even when the formation of an image is ready to be started in a state in which the photosensitive drum is rotating at constant speed. For this reason, there may be a case where the formation of an image cannot be started until substantially one turn of the photosensitive drum is completed after the rotation speed comes to be a constant speed, and in this case, FPOT lowers.
For example, if the photosensitive drum of 80 mmφ is rotated at a surface speed of 251 mm/sec, the time period required for one turn of the photosensitive drum is as follows.80*3.14/251−251 mm/251=1 sec
In a case where the acceleration control of the photosensitive drum is completed and switches to the constant-speed control immediately after the rotation position mark 1121 passes the rotation reference position sensor 1120, the formation of an image cannot be started until the rotation position mark 1121 passes the rotation reference position sensor 1120 next time. Namely, the output of an image delays about one second at the maximum, and this causes considerable deterioration of performance for printers assuming correction.
Here, if the time period required for stabilization of the rotation speed of the polygon mirror is longer than the time period required for stabilization of the rotation speed of the photosensitive drum, the formation of an image cannot be started until the rotation speed of the polygon mirror stabilizes, and hence the above described problem is alleviated or does not arise. However, because polygon mirrors of recent years have been increasingly reduced in weight, and the rotation speed of the polygon mirror stabilizes within a short time period than the time period required for stabilization of the rotation speed of the photosensitive drum. For this reason, in response to stabilization of the rotation speed of the photosensitive drum, image forming apparatuses of recent years go into a state of readiness to carry out image formation. Thus, the above described problem may arise. | {
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The present invention relates to powder material compacting presses, more particularly to an improved die and punch assembly for powder compacting presses.
In powder compacting presses as disclosed in U.S. Pat. Nos. 3,328,840; 3,344,213, 3,328,842; 3,414,940; 3,561,054; 3,726,622; 3,741,697; 3,775,032; 3,805,370 and 3,822,974, all assigned to the same assignee as the present application, there are disclosed apparatus such as presses and tools for such presses for compacting powder material, such as powdered metal, ferrite, glass and other materials into diverse articles such as toroids, beads, pellets and the like. In the powder compacting apparatus disclosed in the aforementioned patents, the articles are formed in single or multi-cavity dies, in which reciprocable punches are disposed, by compaction of the powder material between the punch end face and an anvil displaceable over the die cavity so as to overlap the die cavity.
A work station positioner assembly, forming part of the press apparatus, is disposed angularly or linearly movable over the die plate and is provided with three separate or integral elements, a powder dispenser unit, an anvil, and a pick-up head. The powder dispenser unit is first positioned over the die cavity to fill the die cavity with a predetermined amount of powder material. The dispenser unit is then removed from above the work station positioner assembly, and the anvil unit is in turn positioned over the die cavity and clamped in position. The punch is reciprocated upwardly in the die such as to compact the powder material between the punch end face and the anvil. The anvil is then unclamped from above the die cavity and replaced by the pick-up head as a result of further angular or linear motion of the work station positioner assembly. The punch is reciprocated upwardly so as to eject the compacted article from the die cavity into the pick-up head for transfer to a remote station, or, alternatively, for transfer to a collection station by subsequent motion of the work station positioner assembly.
By way of utilizing standardized punch and die assemblies in the form of interchangeable tool capsules, all adapted to be interchangeably mounted on the press table in an appropriate mounting aperture, with the die plate disposed in the mounting aperture and held therein by any convenient means such as by mounting bolts, the remaining of the tool capsule projecting below the press table, with the punch actuating mechanism of the press appropriately connected to the punch actuating plate portion of the tool capsule, it is a simple matter after a production run of a particular part to remove a tool capsule and replace it by another tool capsule for compacting a different part. With the exception of the die bushings, the punches, and the core rods, if any, all the other mechanical parts forming the tool capsule are subject to little or no wear. The die bushings, the punch and the core rods, if any, are however, subject to important load stresses and to wear, as a result of which they may experience dimensional changes, such as a progressive opening of tolerances, and, if subjected to abnormal loads, they may be damaged beyond repair or even break. It is therefore convenient for the user to provide a tool capsule which can be easily dismantled and which provides easy removal of the die bushings, punches and core rods, when they become worn or when they break, for replacement by new die bushings, punches and core rods. It is also desirable that replacement die bushings, punches and core rods be reinserted in the tool capsule without too much fuss, without requiring complicated fixtures and gauges, and that the diverse replacement elements be held securely in position in proper alignment, as lack of alignment and incorrect positioning may result in breakage or in obtaining finished parts not conforming to specifications. | {
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A Redundant Array of Independent Disks (RAID) is a set of disk drives which can regenerate user data when a drive fails by using redundant data stored on the drives. There are five levels of RAID commonly recognized as described by Patterson, D., Gibson, G. and Katz, R. H., Reliable Arrays of Inexpensive Disks (RAID), June 1988, ACM SIGMOD Conference 1988, pp. 109-116. The RAID Level 5 disk array uses a parity technique to achieve high reliability and availability. A parity block protects the data blocks within its parity group. The parity block is the result of exclusive OR (XOR) operations of the data blocks in its parity group. Each block in a parity group is stored on a different disk drive of the array. In RAID 5, the parity blocks are stored on all the disks (with data blocks from other parity groups).
A RAID 5 disk array is robust against single disk crashes. If a disk fails, data on the disk can be recreated by reading data from the remaining disks in the array and performing the appropriate exclusive OR operations.
Whenever a request is made to update a data block, the corresponding parity block must also be updated to maintain consistency. Since the parity must be altered each time the data is modified, RAIDs require four disk accesses to update a data block: (1) Read the old data; (2) Read the old parity; (3) Write the new data; and (4) Write the new parity. The need for four disk accesses per update is often referred to as the RAID-5 update penalty. Following the required four disk accesses, the completion of the update is presented to the host system.
RAID is typically implemented in disk controllers having specialized hardware. XOR hardware performs the XOR operation to compute parity. Non-Volatile RAM (NVRAM) also referred to as a cache improves RAID performance and reliability. These RAID implementations are referred to as hardware RAIDs. Some low cost hardware RAIDs do not have an NVRAM or have a small NVRAM. A software RAID is implemented purely in software running on a host computer. Software RAIDs do not have access to special hardware, so they often need to use specialized algorithms. In particular, software RAIDs do not have access to NVRAM often used by hardware RAIDs to mark inconsistent parity groups and recover from power failures.
More sophisticated hardware RAIDs use NVRAM to improve write performance by implementing write caching (maintaining the write in the cache for easier access by the system) and fast write (considering a write operation to be complete when it is written in the NVRAM). Other hardware RAIDs use NVRAM solely for the purpose of marking inconsistent parity groups (parity groups where the new data has been written but the new parity has not yet been written) and recovering from power failures in the middle of update requests.
An example of a software RAID is the Paragon system from Chantal/BusLogic Corporation or the Corel RAID system from the Corel corporation. Both of these systems are for the Novell Netware servers.
Current software implementations of RAID 5 require a complete scan of all disk blocks following a power failure or a system crash to find and fix inconsistent parity groups. Long recovery times are unacceptable for most practical implementations.
A disk failure during recovery can cause data loss. The data on the broken disk would normally be reconstructed using the data from the other disks. However, if the parity group was inconsistent the data can not be accurately reconstructed. A related problem with having to scan all parity groups during recovery is that if one of the data blocks in a parity group cannot be read (uncorrectable ECC error on the disk block, for example), there is a data loss situation, since the parity group may be consistent. The more the parity groups that have to be scanned, the more likely a data loss situation will occur. Another secondary problem is that parity groups are locked for too long of a time, since the data and parity are written sequentially and the lock is held until both are written to disk.
In Chen, P. M. et. al., RAID: High-Performance, Reliable Secondary Storage, ACM Computing Surveys, June 1994, vol 26 (2); pp 145-186, a system is proposed where every time a write is made to a parity group, an indicator is written to the disk that the parity group has been modified. Such a write requires six disk accesses: (1) Write indicator that the parity group is modified; (2) Read the old data; (3) Read the old parity; (4) Write the new data; (5) Write the new parity; and (6) Write indicator that parity group is not modified. Chen proposes keeping a fixed-size list of parity sectors that might be inconsistent. This list is maintained on disk and in memory. Chen reduces the number of disk I/Os needed to maintain this list by using a group commit mechanism. This improves throughput at the expense of increased response time.
In general, previous software RAID proposals have not included discussion of concurrency and locking issues related to RAIDs. To the extent such discussion has existed, the assumption has been that locking is used to prevent more than one update concurrently executing against a parity group. It is also desirable to optimize concurrent processing of multiple updates against a parity group. | {
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Medication noncompliance is the highest determinant of relapse in schizophrenia. Therefore, a therapy method that helps patients remain on medication for extended periods would substantially improve clinical outcomes. Current methods of administering anti-schizophrenia medication (e.g. risperidone) provide dosing for one month or less. Thus, methods of providing therapeutic levels of risperidone and other medications are needed in the art. | {
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(a) Fields of the Invention
The present invention relates to semiconductor devices, and in particular to electrostatic protection semiconductor devices capable of protecting their internal elements against breakdown due to an electrostatic surge or the like.
(b) Description of Related Art
Recently, with increasing packing density and decreasing power consumption of a semiconductor integrated circuit device, a driver for driving an inductive load has also been requested to increase the packing density and decrease the power consumption.
Herein, the inductive load is a load to which a voltage is applied from outside to pass a current and to generate an induced voltage having a polarity opposite to that of the applied voltage. A concrete example of the inductive load is a motor.
However, a semiconductor device having a driver for driving the inductive load formed therein requires avoiding misoperation of a driver element for driving the inductive load and of an element directly connected to that element.
One exemplary technique for attaining this object is disclosed in Japanese Unexamined Patent Publication No. S61-189662 (referred hereinafter to as Document 1). This technique disclosed is that an island region is provided between a driver element and other circuit elements and the potential of the island region is kept high to prevent misoperation of these elements. Another exemplary technique is disclosed in Japanese Unexamined Patent Publication No. H10-256484 (referred hereinafter to as Document 2). This technique disclosed is that a surge protection element is placed sufficiently away from a driver element.
The technique for avoiding misoperation mentioned in Document 1 will be described below with reference to the accompanying drawings.
FIG. 8 is an equivalent circuit diagram of a semiconductor device mentioned in Document 1.
The semiconductor device includes an output pad 11 electrically connected to an inductive load (not shown), and a driver element 12 electrically connected to the output pad 11 and supplying a current. At a connecting point N11 positioned between the output pad 11 and the driver element 12, a negative surge absorbing unit 13 and a positive surge absorbing unit 14 are electrically connected to each other.
In this device, the negative surge absorbing unit 13 is provided with a negative surge protection diode 15 and a GND (grounding) terminal 16. The negative surge protection diode 15 has a cathode 15K electrically connected to the connecting point N11 and an anode 15A connected to the GND terminal 16. With such a configuration, if the output pad 11 has a negative potential to generate a surge, the negative surge protection diode 15 is activated to absorb the negative surge.
The positive surge absorbing unit 14 is provided with a positive surge protection diode 17 and a power supply terminal 18. The positive surge protection diode 17 has a cathode 17K connected to the power supply terminal 18 and an anode 17A electrically connected to the connecting point N11. With such a configuration, if the output pad 11 has a positive potential to generate a surge, the positive surge protection diode 17 is activated to absorb the positive surge.
Next, FIGS. 9 and 10 are views showing the structure of the negative surge absorbing unit 13 and its peripheral portion in the semiconductor device. FIG. 9 is a sectional view and FIG. 10 is a plan view. In these figures, other components of the semiconductor device shown in FIG. 8, such as the output pad 11 and the driver element 12, are provided at locations in the device which are not shown in FIGS. 9 and 10.
In the semiconductor device 20 shown in FIG. 9, an n-type epitaxial layer 22 is formed on a p-type semiconductor substrate 21, and LOCOS (local oxidation of silicon) films 23 are formed at predetermined positions on the surface of the n-type epitaxial layer 22. The n-type epitaxial layer 22 is divided into multiple regions by a p-type isolation layer 24. To be more specific, the p-type isolation layer 24 defines a protection diode region 25, an n-type peripheral region 26, a control circuit region 27, and other regions.
In this structure, the p-type isolation layer 24 is composed of a heavily p-doped layer 24a formed in and below the surface of the n-type epitaxial layer 22, a p-type upper isolation layer 24b formed below the heavily p-doped layer 24a, and a p-type lower isolation layer 24c formed below the p-type upper isolation layer 24b to extend across the p-type semiconductor substrate 21 and the n-type epitaxial layer 22.
In each of the protection diode region 25, the n-type peripheral region 26 and the control circuit region 27, an n-type buried layer 28 is formed at and through the interface between the p-type semiconductor substrate 21 and the n-type epitaxial layer 22.
In each of the protection diode region 25 and the n-type peripheral region 26, the surface of the n-type epitaxial layer 22 is formed with a heavily n-doped layer 29, while in the control circuit region 27, the surface of the n-type epitaxial layer 22 is formed with a p-type resistive layer 30.
An interlayer insulating film 31 is formed to cover the n-type epitaxial layer 22 and the components formed on its surface. The interlayer insulating film 31 is formed with openings, which are formed with contacts 32 for providing electrical connections to the heavily p-doped layer 24a and the heavily n-doped layer 29 of the protection diode region 25, the heavily n-doped layer 29 of the n-type peripheral region 26, and the p-type resistive layer 30.
Note that the connecting point N11, a terminal with a fixed potential V, a terminal with a GND potential, and the like are also shown in FIG. 9. However, these components are shown simply for the purpose of illustrating electrical connections from corresponding portions of the semiconductor device to these components, and these components are not shown as part of the structure of the device.
Also, as shown in FIG. 10, the p-type isolation layer 24 defines the protection diode region 25, the n-type peripheral region 26, and the control circuit region 27 to surround them. Note that the LOCOS film 23 and the interlayer insulating film 31 are omitted in FIG. 10.
In the control circuit region 27, in addition to a resistance element using the p-type resistive layer 30, required electric elements such as a transistor 33 are formed.
In the protection diode region 25 of this device, the contacts 32 provided on the p-type isolation layer 24 are grounded to the GND potential terminal, and the heavily n-doped layer 29 is electrically connected to the connecting point N11. In the n-type peripheral region 26 thereof, the heavily n-doped layer 29 is electrically connected to the fixed potential terminal having a higher potential than the GND potential.
Since the device has the structure described above, the negative surge protection diode 15 is formed in the protection diode region 25 (see also FIG. 8). To be more specific, the negative surge protection diode 15 is formed which uses the p-type isolation layer 24 and the p-type semiconductor substrate 21 as the anode 15A, and the n-type buried layer 28, the n-type epitaxial layer 22, and the heavily n-doped layer 29 as the cathode 15K.
If the output pad 11 electrically connected to the inductive load has a negative potential, a parasitic NPN transistor 51 is activated which is composed of the n-type peripheral region 26, the p-type isolation layer 24 included in the p-type semiconductor substrate 21 and the protection diode region 25, and the heavily n-doped layer 29 of the protection diode region 25. As a consequence of this, a current is supplied mainly from the n-type peripheral region 26 serving as a collector of the parasitic NPN transistor 51, so that only a reduced amount of current flows through the p-type semiconductor substrate 21.
Also in this device, a parasitic thyristor 52 is formed to extend from the p-type resistive layer 30 of the control circuit region 27 to the heavily n-doped layer 29 of the protection diode region 25. This may cause misoperation of the control circuit region 27. However, the parasitic thyristor 52 has a configuration less likely to be activated.
Specifically, part of the p-type semiconductor substrate 21 included in the n-type peripheral region 26 serves as a p-type gate portion. The presence of the n-type peripheral region 26 increases the width of the p-type gate portion. This results in a decreased current gain of the NPN transistor which is part of the parasitic thyristor 52. From the above result, the parasitic thyristor 52 is hard to activate. Therefore, even if the output pad 11 has a negative potential to generate a surge, misoperation of the control circuit region 27 can be prevented.
FIG. 11 is an equivalent circuit diagram of the semiconductor device mentioned in Document 2.
The semiconductor device includes an input/output pad 11a electrically connected to an inductive load, and a control circuit 19. At a connecting point N21 positioned between the input/output pad 11a and the control circuit 19, a negative surge absorbing unit 13 and a positive surge absorbing unit 14 are electrically connected to each other.
Although detailed description of the negative and positive surge absorbing units 13 and 14 is omitted, they have the function of absorbing negative and positive surges, respectively, as in the case of the technique of Document 1 shown in FIG. 8.
The semiconductor device is also provided with a driver element 12. In this device, the driver element 12 is placed a sufficient distance A away from the negative surge protection diode 15.
FIG. 12 is a view exemplarily showing the plan structure of the semiconductor device which attains the equivalent circuit diagram in FIG. 11. This figure illustrates the negative surge absorbing unit 13.
Referring to FIG. 12, the semiconductor device has regions defined by the p-type isolation layer 24. Specifically, it is formed with a protection diode region 25 and a control circuit region 27 similar to those of the semiconductor device in FIG. 10.
That is to say, in this device, a negative surge protection diode 15 is formed which includes the p-type isolation layer 24, an n-type buried layer 28, and a heavily n-doped layer 29, and the heavily n-doped layer 29 is electrically connected to the connecting point N21 on an interconnect electrically connecting the input/output pad 11a to the control circuit 19.
Further, the driver element 12 surrounded with the p-type isolation region 24 is arranged a sufficient distance A away from the protection diode region 25.
In the device thus configured, if the driver element 12 has a negative potential to generate a surge, a parasitic NPN transistor may be activated which uses the n-type buried layer 28, the heavily n-doped layer 29, and the like as a collector, the p-type isolation region 24 and the like as a base, and an n-type epitaxial layer of the driver element 12 as an emitter. However, since the negative surge protection diode 15 and the driver element 12 are arranged sufficiently away from each other, the p-type isolation region corresponding to the base has a high resistance. This prevents activation of the parasitic NPN transistor. Owing to this, misoperation of the control circuit region 27 is avoided. | {
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Minimally Invasive Surgery (MIS) is a growing field including both laparoscopic and robotic operations. Surgeons and engineers are making continual efforts to mitigate the negative effects of procedures on patients. Reducing the size of the surgical instruments is one effective method pursued in this effort. In some examples, surgical instruments may include wrist mechanisms. Also, other areas such as robotics may use wrist mechanisms. For instance, wrist mechanisms are commonly used in a wide variety of grasping, cutting, and manipulating operations. In some examples, wrist mechanisms may allow control of an angle of a tool with respect to a mounting shaft. Typically, the wrist mechanism is placed at the end of the shaft, before the tool (e.g., cutter or grasper) to improve the dexterity of the tool. In some conventional examples, the wrist mechanism may be one or more hinges that permit the tool to move with respect to the shaft with two degrees of freedom. However, in some examples, these conventional wrist mechanisms may produce large swept volumes when they move due to the distance between centers of rotation for the two degrees of freedom. Also, due to manufacturing constraints and the increased importance of friction at small scales, it may be challenging to produce a small-scale wrist mechanism that is relatively easy to manufacture and assemble. | {
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Restaurants and institutions commonly hold and serve hot foods from electrically operated countertop food warmers. Water is usually, but not necessarily, used in the wells of the warmer to act as a heat transfer medium and to improve thermal efficiency. These warmers are designed to hold 12".times.20" steam table pans or combinations of fractionally sized pans in various depths with the use of an adaptor plate formed from a sheet of metal with one or more openings. The warmers may also be used to hold a variety of round shouldered vegetable pans or inserts. The rectangular vegetable pans or inserts are supported by a lip which extends outwardly at the top of the pan and rests on the top edge of the warmer well. In addition to support, the lip acts as a loose seal to prevent the escape of large amounts of steam from the area between the bottom of the well and the bottom of the pan. Like the rectangular pans, the adaptor plates also have lips and flanges to provide support and act as a steam seal.
The arrangement commonly employed for use in restaurants and cafeterias prior to the present invention is exemplified by U.S. Pat. No. 4,284,880 which describes a metal food pan surrounded by an insulated housing that has a pair of spaced apart metal walls between which is stuffed fiberglass insulation. An electrical heating element provided in the unit is not exposed to the metal food tray but is instead mounted below a metal plate which is itself spaced a few inches below the food tray. U.S. Pat. No. 4,215,267 is similar except that the electrical heater is mounted below a heavy heat distribution plate. Heat is not transmitted efficiently to the food tray in these devices because the electric heater is in physical contact with the housing and is not facing, i.e., exposed directly to, the food tray. Moreover, the double-walled housing filled with insulation is expensive, time consuming to assemble, and presents an undesirable environmental impact. U.S. Pat. No. 5,045,672 is generally similar except that the water pan which consists of a single thickness of sheet metal will suffer from substantial heat losses, defeating a primary objective of the invention which is to provide excellent thermal efficiency while at the same time eliminating the need for an expensive insulation-filled metal housing.
U.S. Pat. No. 3,130,288 discloses a food service device which includes a deep outer pan containing a water bath and an inner tray for holding food. Both the tray and the pan are formed from transparent plastic sheet material such as a thermoplastic (Lucite or Plexiglas) or a thermosetting material. An electric heating element is placed in contact with the inside of the pan. This device has several shortcomings. First, the electric heater can cause localized overheating and damage to the material from which the pan is formed. More importantly, because both the food tray and the water bath pan are formed from plastic material, they are both heat insulators. Consequently, heat is not transmitted efficiently to the food. Finally, much infrared radiation will escape through the transparent plastic walls of the unit.
In view of these and other deficiencies of the prior art, it is one object of the invention to provide an improved food warmer for restaurants, cafeterias and the like in which heat loss is minimized and the requirement for an expensive fiberglass-filled sheet metal housing is eliminated while at the same time enabling heat to be conducted very efficiently from the electric heating element to the food within the food tray.
Another object of the invention is to provide a food warming device for cafeterias, restaurants and the like having a rigid monolithic sump vessel of a composition which provides excellent strength and impact resistance, outstanding heat insulating qualities and is not subject to stress cracking or other damage after repeated cycles of exposure to boiling water over a period of many months or years of use.
These and other more detailed and specific objects of the present invention will be apparent in view of the following description setting forth by way of example but a few of the various forms of the invention that will be apparent to those skilled in the art once the principles described herein are understood. | {
"pile_set_name": "USPTO Backgrounds"
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Coating of a metallic pigment has been conventionally performed to impart metal texture to a resin molded article such as a thermoplastic resin molded article or the like. Such coating has to be carried out through complex steps including a surface cleaning step, a preliminary coating step and a drying step. An expensive apparatus is required in this coating process, which leads to an increase in process cost. In the event that detective products generated in the coating process and products collected after use are pulverized and recycled, the impact strength of recycled resins is sharply reduced and cannot be reused. Thus the detective products and the used products are disposed as wastes. This poses a problem of increased cost and environmental pollution.
As a solution to this problem, there are available different molding methods that make use of a thermoplastic resin composition containing a metallic pigment. For example, U.S. Pat. No. 6,280,837 discloses a resin molded article formed of a thermoplastic resin composition in which a brightening agent, such as an aluminum powder, a pearly mica pigment or a flaky glass powder, and a coloring agent are directly mixed with a synthetic resin. U.S. Pat. No. 6,143,815 discloses a resin molded product in which a scaly brightening agent having a particle size of 10 to 20 μm in accordance with mixed with a thermoplastic resin. U.S. Pat. No. 5,530,051 discloses a polyester-based resin molded article including metallic micro-plates having an average particle size of 80 to 800 μm and an average shape ratio of 1/100 to 1/8, the metallic micro-plates formed by cutting a metal plate to have a partial cutout portion.
In the prior art cited above, however, the metals used as the metallic pigment are not arranged in a specified direction in an injection molding process but are distributed vertically or obliquely as resin flows join each other. As a result, light is unevenly reflected only in a specific portion. This makes it impossible to obtain a uniform metal color.
In other words, as shown in FIG. 1, if a molded article is produced using a scaly or plate-like metallic pigment, the metallic pigment 100 is not oriented in a specified direction in an injection molding process. In the flow merge line where different resin flows meet each other, the metallic pigment is distributed at an angle perpendicular to or substantially perpendicular to the major surfaces of a molded article. This phenomenon occurs in the portions where the thickness of the molded article is changed. As a consequence, the reflection of light becomes uneven, which makes it impossible to obtain a uniform metal color.
In addition, the metallic pigment 100 protrudes on the product surface, thereby reducing the brightness. A plate-like aluminum pigment protruding on the product surface tends to increase friction on the product surface, consequently reducing the scratch resistance. Moreover, the metallic pigment 100 reduces the stability and durability of the product surface when exposed to a high temperature, a low temperature or ultraviolet rays. This results in a reduced lifespan of the product. | {
"pile_set_name": "USPTO Backgrounds"
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In the speed evaluation in an electronic diesel control (EDC) for diesel engines, it is known to use the so-called "segment" method in which engine speed is calculated by measuring the time interval between the passing of two successive marks (reference marks) on the engine crankshaft, these marks being equally angularly spaced. Four marks are provided for a four cylinder engine. During idling, the engine speed tends to fluctuate widely at a relatively low frequency, e.g. 5 Hz, due to the resilient mounting of the engine on the vehicle body or chassis. It is an object of the EDC to damp or suppress these low frequency speed fluctuations but superimposed on these low frequency fluctuations is a higher frequency fluctuation, e.g. 25 Hz for a four stroke four cylinder engine rotating at 750 r.p.m. This is due to the fluctuating torque produced by the combustion pressures developed in the individual engine cylinders. Using the known method, the output speed signals are almost in phase with the perfect 5 Hz waveform from which the 25 Hz frequency has been eliminated. However, the output speed signals still possess the 25 Hz component which is disadvantageous for the EDC, inasmuch as it is impossible for the EDC to compensate for the speed fluctuations due to the individual momentary combustion pressures. The 25 Hz component can be effectively eliminated by taking averages of the input speed signals but this leads to a phase delay between the perfect 5 Hz waveform and the output waveform, because the average pertaining to one reference mark cannot be calculated until a subsequent reference mark has passed.
EP-A-0 133 426 describes a method of obtaining an average value of an almost periodically fluctuating signal, such as the angular velocity of the crankshaft of a diesel engine. To obtain a tone average, it is necessary to take the coverage, such as a running average, over one or several complete periods of fluctuation. However, when the engine speed changes suddenly, a corresponding change is not reflected in a corresponding sudden change in the average value as taken but only in a gradual change. To avoid this, EP-A-0 133 426 proposes to store the angular velocity signal at discrete points and to process the stored signal values later, e.g., by comparing the stored signal values with later actual signal values. Such comparison, in the event of a change in engine speed, results in a transient deviation. A running average is also taken of the fluctuating signal representing the angular velocity of the crankshaft and any transient deviation is added to this running average to obtain an output value which accurately represents the average engine speed at any given time. Disadvantages of the method of EP-A-0 133 426 are that it requires a large storage capacity and maybe additional memory components, special measures, with resulting expense, must be taken to ensure that the stored angular velocity values and the actual values with which they are compared are in synchronism with one another, requiring additional components, and the comparison of the stored and actual values representing the course of the fluctuating signal demands large computer capacity and the large computation times offset the advantage of the method in that a rapid engine speed response is obtained. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The present invention pertains to data storage devices where data is stored in a material that is reversibly convertible between detectable states in response to the input of energy. More particularly, the present invention pertains to a method for initializing a data storage device having a phase change data storage medium that is convertible between detectable states.
2. Description of the Background Art
Writable data storage or memory devices have been fundamental in furthering the technology driven information age. Included in writable data storage devices are the now highly commercialized and widely distributed phase change data storage medium.
An enormous consumer demand for writable and rewritable memory storage devices presently exists. Mass production of writable and rewritable memory storage devices in the form of phase change information data storage devices is currently underway to meet this consumer demand. For example, one well-known data storage device is the phase change optical memory disk. The typical optical memory disk may have a variety of layers to effect data storage, including a protective layer, a reflective layer, an upper dielectric layer, a phase change medium, a lower dielectric layer, and a disk substrate. The layers of the optical memory disk may also be formed in other configurations as well.
The phase change optical disk is a device with multiple detectable states that allow for the storage of data. For example, a phase change optical data storage device may have a chalcogenide memory material used as the active memory layer. The chalcogenide memory material may have an amorphous state, a crystalline state and varying intermediate states. When the phase change material is deposited on a disk, the material is formed in an essentially amorphous state. The crystallization characteristics of the material are different in first crystallization from all subsequent crystallizations. Therefore, the disk must be crystallized once before the disk is ready for use. This first crystallization is referred to as initialization. Thus, preparation of a newly manufactured phase change data storage device requires that the device be initialized into a crystalline state so that data can be reliably written and erased.
Present day disk initialization is typically carried out by directing a continuous laser beam along a track of an optical disk as the disk rotates. The laser energy is utilized to change the recording medium from an amorphous state to a crystalline state. An example of this process has been described in U.S. Pat. No. 5,768,221 which issued to Kasami et al. Therein is disclosed a method for initializing an optical recording medium by rotating a disk at a speed of 1000 rpm and directing a laser beam upon a small portion of the recording medium. The laser beam then moves from the inner most to the outermost circumference sections of the disk. Therefore, as the method serially initializes the disk, the method is relatively slow and does not lend itself to efficient mass production.
One attempt made at initializing the entire optical disk with a single energy exposure has been described in U.S. Pat. No. 5,684,778, which issued to Yamada et al. on Nov. 4, 1997. The Yamada patent discloses a process for initializing a phase change recording medium using flash light emission which drops the emission strength instantly to a zero level immediately after crystallization . The method teaches the necessity of exposing the disk to a single flash or single discharge of high intensity light for 0.1 to 10 msec with no residual exposure. The waveform described in the Yamada patent claims to fully and completely crystallize the phase change recording medium with the single energy exposure. Yet, as the patent admits, problems invariably arise in alleviating internal stresses and the tendency to cause warp and distortion in the disk, which problems the patent does not solve. Warp and distortion in the recording medium may provide a major cause of malfunction in disks and are therefore undesirable. To compensate for the warp created by the initialization method disclosed in the Yamada patent, said method requires a further step of unwarping or straightening an otherwise unusable disk. Additionally, internal stress can cause cracking and/or delamination of various layers within the optical disk. As such, methods of flash initialization, as presently known, are not desirable for large-scale commercial purposes.
Thus, present day methods for initializing phase change memory devices result in a reduction of production cycle time and increased manufacturing costs.
To address the above mentioned problems and others, the present invention provides a method for initializing a phase change information storage device including the steps of: providing a data storage device having a phase change data storage medium; exposing substantially all the phase change data storage medium with a first, energy exposure for about 1 xcexcsec or less. The first exposure is then followed by at least one additional energy exposure to complete initialization in a short period of time with reduced device damage and warp.
The initialization process may be accomplished by variations upon the present method, as will become evident from the ensuing disclosure, all of which are desired to be protected by the claimed invention, but in any event will require exposing the data storage medium to a first or pre-initialization energy. The pre-initialization energy is preferably delivered to the data storage medium as a predetermined waveform over a predetermined time with a power and spectral content suitable for initializing a memory device with reduced damage. Such a waveform preferably includes an initial pulse or burst of energy having a rise in intensity, a maximum intensity, and a decline in intensity over a period or duration of 1 xcexcsec or less. The waveform, energy level and spectral content act to pre-initialize the data storage medium. The initial pulse of energy is then followed by one or more additional exposures of energy, which complete the initialization process with reduced warp and device damage.
The method for initializing a memory device in accordance herewith is especially useful for initializing phase change optical disks, such as CDxe2x88x92RW, PD, DVDxe2x88x92RAM, DVDxe2x88x92RW, DVD+RW, multi-level optical disks, multi-layer optical disks, as well as others.
For a more complete understanding of the present invention, reference is made to the following detailed description and accompanying drawings. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The present invention relates to a bleaching detergent composition showing excellent performance for both the detergency against sebum dirt stains and that against lipophilic dirt stains, such as yellowish stains of underwear. In the present invention, the term "yellowish stains" used herein refers to a color change of white underwears to yellowish color by deposition and accumulation of excreta.
2. Discussion of the Related Art
Conventionally, various proposals have been made to improve detergency against yellowish stains caused by detergent compositions by formulating bleaching agent components to the detergent compositions.
For example, Japanese Patent Laid-Open Nos. 59-22999 and 6-316700 disclose bleaching agent compositions and bleaching detergent compositions, each containing an organic peracid precursor which produces an organic peracid having an alkyl group with a particular number of carbon atoms, and a hydrogen peroxide releasing material. The organic peracids produced from the organic peracid precursors mentioned above show remarkably excellent bleaching power against dirt stains, but in cases where the organic peracid precursors are added to ordinary detergent compositions to make bleaching detergent compositions, sufficiently good bleaching effects cannot be obtained. The reasons therefor are presumably as follows: Since the surfactant concentration, particularly a nonionic surfactant concentration, is very high in these detergent compositions, the organic peracid precursors are enclosed in the surfactant micelle and dissolved therein. Therefore, the reaction of the organic peracid precursors with the hydrogen peroxide releasing material is notably inhibited, thereby preventing the generation of organic peracids, which are bleaching species. Higher the proportion of the nonionic surfactants in the surfactant components, more notable the inhibition of the reaction of the organic peracid precursors with the hydrogen peroxide releasing material becomes. For the reasons given above, the formulation of the nonionic surfactants in an effective amount has been difficult, when compared with anionic surfactants, thereby making it impossible to satisfy both the detergency against the sebum dirt stains and the detergency against the yellowish stains of underwear.
On the other hand, the present inventors have found that a high detergency can be performed against the sebum dirt stains even when the concentration of the surfactant used is notably reduced by using a crystalline alkali metal silicate having an alkaline capacity in a high concentration and improving metal ion capturing ability. However, in this washing method, a sufficient washing performance against the lipophilic dirt stains, such as yellowish dirt stains on underwear, cannot be achieved.
Examples of detergent compositions where a crystalline silicate and a bleaching component are essential components include Japanese Patent Laid-Open Nos. 6-116591 and 7-53992. The above publications pertains to bleaching detergents comprising sodium crystalline silicates, surfactants, and bleaching components comprising bleaching activating agents which produce peroxy fatty acids and sodium percarbonate. The bleaching detergents having compositions disclosed in these references have insufficient detergency against the sebum dirt stains. In addition, since the compositional ratio of the surfactants are high, the composition does not allow to effectively produce organic peracids by the bleaching activating agents (organic peracid precursors). Therefore, sufficient effects in removing lipophilic dirt stains, such as yellowish dirt stains on underwear, cannot be obtained. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The present invention relates to a thin film deposition apparatus and a method of maintaining the same.
2. Description of the Related Art
In manufacturing semiconductor devices, various apparatuses and processes have been developed to provide a high quality thin film on a substrate. Several methods have been used to form a thin film, employing surface reaction of a semiconductor substrate. The methods include vacuum evaporation deposition, Molecular Beam Epitaxy (MBE), different variants of Chemical Vapor Deposition (CVD) (including low-pressure and organometallic CVD and plasma-enhanced CVD), and Atomic Layer Epitaxy (ALE). ALE was studied extensively for semiconductor deposition and electroluminescent display applications, and has been more recently referred to as Atomic Layer Deposition (ALD) for the deposition of a variety of materials.
Certain deposition apparatuses include one or more reactors housed in a chamber. Each of the reactors may include a substrate support on which a substrate is mounted.
It is sometimes necessary for a technician to have access to the interior of a chamber. Such a chamber is typically provided with a cover, which, when removed, allows access to components within a chamber. When such a cover is in the closed position, it provides a sealed environment within the chamber. Such a cover is typically manually dismounted and removed to gain access to the interior of the chamber.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form prior art already known in this country to a person of ordinary skill in the art. | {
"pile_set_name": "USPTO Backgrounds"
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Normally, an alarm signal is transmitted directly from the protected premises to a commercial alarm receiving centre. When this signal is received, a manual verification process may commence to try and ascertain whether the signal is false or a true indication of an alarm condition at the premises. The outcome of any such procedure will determine whether the emergency services are informed of the alarm situation.
A significant percentage of alarm conditions relayed to the emergency services via commercial alarm receiving centres prove to be false alarms. In many cases these false alarms result from errors on the part of the alarm system user at the premises, e.g incomplete disarming of an intruder alarm as the premises are opened up at the start of the working day, or inaccuracies in the way in which an intruder alarm is armed at the end of the working day.
In order to more effectively filter these alarms conditions and thus reduce the number of false calls relayed to the emergency services, some organisations (such as banks, building societies, local education authorities), who operate high numbers of alarm sensors at diverse premises have set up their own "in-house" monitoring centres, which are used in place of commercial alarm receiving centres. These in-house alarm monitoring centres use their knowledge concerning the operation of their premises to filter signals more effectively and virtually eliminate false alarms due to user error. | {
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This invention relates to photographic apparatus for use with transmission electron microscopes (TEM). More particularly, it concerns such apparatus which is adaptable to presently existing TEM machinery designs without modification of that machinery and which makes possible TEM exposure and immediate processing of instant film exemplified by diffusion transfer film emulsions and related processing chemistry.
TEM machines are capable of providing an image of a specimen with a magnification factor of up to one million times and are used extensively in such fields as pathology, biology, chemistry, metallurgy and other industrial applications for visible observation of such magnified images. Although the magnified electron image may be observed directly when focused on a fluorescent screen or by using other forms of electronic imaging devices, the resolution of detail in such directly observable images is much lower than the resolving capacity of photographic emulsions. For this reason, as well as for providing permanent records of TEM magnified images of specimens, TEM machines are conventionally equipped with photographic film exposing systems to enable visual observation of high resolution detail in the magnified specimen image. Moreover, final analyses of a given specimen is usually delayed until one or more photographs of the TEM image are available for observation.
TEM machines are extremely expensive, currently priced in the hundreds of thousands of U.S. dollars, and as such, each machine represents a major investment to a research laboratory. In addition to costly, high power electron beam generating and focusing components, the space or chamber in which the electrons are transmitted must be evacuated to 10.sup.-7 atmospheric pressure or more in order to avoid electron scattering by collision with molecules of air or with molecules of other substances in a gaseous phase. In this latter respect, it is to be noted that all normally liquid and many normally solid substances will vaporize under the magnitude of vacuums developed in the electron chamber of TEM machines. Because the film and film handling accessories of a TEM photographic system are presented in the evacuated electron beam chamber and, moreover, are passed into and out of that chamber, each TEM machine involves costly vacuum sealing mechanisms predicated in substantial part on the physical format of film unit assemblies employed and on the configuration of film containers or boxes to be used in a TEM machine of a given design. Hence, modification of photographic components in presently existing TEM equipment is impractical and, moreover, design changes in photographic apparatus supplied by manufacturers of TEM machines are restricted to accommodation of respective TEM machine designs.
To provide a general understanding of existing TEM machine design and the procedures required in the handling of photographic film to be used in such machines, reference is made to FIGS. 1 and 2 of the accompanying drawings. In FIG. 1, the various photographic equipment and handling procedures in a conventional research laboratory are schematically represented. In FIG. 2, the transfer of individual film units within the TEM machine is diagrammatically depicted.
In FIG. 1, a TEM machine 10 is shown to include a cabinet-like base 12 on which is mounted an electron beam focusing column 14 having a specimen receptor 16 and carrying an electron beam generating head 18 at its upper end. An observation port 20 is customarily provided for viewing a fluorescent plate (not shown) at the base of the column. The cabinet 12 includes a pair of drawers 22 and 24 for receiving respectively a film supply box 26 and a film receiver box 28. In FIG. 2, the film boxes 22 and 24 are shown as they might be oriented within the TEM machine 10 which includes mechanisms (not shown) for transferring individual film units 30 from the supply box 26 to an exposure station aligned with the focusing column 14 and then to the receiver box 28. The evacuated chamber of the TEM machine 10 is generally depicted in phantom lines in FIG. 2 and as such encloses both boxes 26 and 28 within the machine 10.
The film handling procedure now used in TEM laboratories is diagrammatically depicted in FIG. 1 of the drawings. Individual film sheets 32 are removed from a shipping carton 34, manually inserted into a machine compatible carrier plate 36 to provide a film unit 30. The film units 30 are then loaded into a supply box 26 to complete a film preparation procedure carried out in total darkness within a darkroom 38. In larger TEM laboratories, as many as 8 or more TEM machines 10 may be serviced by a single darkroom. Also, it is not uncommon for a laboratory to employ the TEM machines of two or more different manufacturers, each of which requires a unique carrier plate 36, supply box 26 and receiver box 28. Both boxes 26 and 28 employ a light-tight cover or "dark slide", the dark slide 40 of the supply box 26 being closed in the darkroom 38 after it is filled with film units 30.
Prior to use in a TEM machine 10, the loaded supply boxes 26 must be out-gassed in a vacuum chamber 42 for at least 12 hours to assure removal of volatile substances which may vaporize in the vacuum chamber of the TEM machine. As explained above with reference to FIG. 2, in the TEM machine 10, a specimen is inserted into the column 14 and photographed by passing the individual film units 30 from the supply box 26 to an exposure station and then to the receiver box 28. It is desirable with some types of specimens to expose only a few film units 30 and then remove the receiver box 28 (with only the few exposed film units) and return it to the darkroom for development so that the developed images may be observed prior to making further exposures of electron images of the same specimen. In fields such as pathology or where other biological specimens are under observation, the time required for conventional film handling development is often longer than the viable life of the specimen. Hence, it is customary to await development of film until the receiver box 28 is filled.
From the foregoing, it will be appreciated that in the present use of TEM machinery, the attainment of a high resolution photograph of a specimen is a very tedious and time consuming procedure by which the benefits of specimen analysis are significantly delayed. This is particularly true in the field of pathological analysis of tissue removed by surgery or in similar fields where it would be desirable to have the benefit of a TEM photograph available within a short period of time. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The present invention relates to an etching apparatus for a liquid crystal display device, and more particularly, to an etching apparatus enabling to increase productivity by sensing a level of an etchant using a contact sensor and preventing the sensor from being degraded by particles.
2. Discussion of the Related Art
Recently, many efforts have been made to research and develop various flat display panels such as LCD (liquid crystal display), PDP (plasma display panel), ELD (electroluminescent display), VFD (vacuum fluorescent display), and the like. LCD is practically used because of the characteristics or advantages of high quality image and low power consumption.
The liquid crystal display device includes lower and upper substrates confronting each other to leave a predetermined interval from each other and a liquid crystal layer formed between the substrates. A black matrix and a color filter layer are formed on the upper substrate. And, on the lower substrate formed are a plurality of gate and data lines arranged horizontally and vertically with a predetermined interval from each other to define pixel areas and thin film transistors and pixel electrodes formed in the pixel areas, respectively.
Lightweight and compact size are demanded for the liquid crystal display device to be applied to portable TV set, notebook computer, and the like. Yet, the structure or technology of the liquid crystal display device has limitation for the lightweight and compact size. However, the glass substrate as a basic element of the liquid crystal display device is the heaviest in the components of the liquid crystal display device. Hence, many efforts are made to reduce the weight of the glass substrate.
In order to reduce the weight of the glass substrate, a thickness of the glass substrate should be decreased. Yet, a physical force is occasionally applied to the glass substrate in the process of fabricating the liquid crystal display device. And, the glass substrate undergoes a number of heating and cooling processes. Hence, the thin glass becomes easy to be broken. Recently, used is a new method including the steps of using a thick glass substrate in the early stage of process and thinning the glass substrate in the later process. Namely, devices and color filters are formed on thick glass substrates to prepare upper and lower glass substrates, the upper and lower glass substrates are bonded to each other, and then outer surfaces of the glass substrates are etched to reduce an overall thickness of the liquid crystal display device.
Generally, the glass substrate is etched by wet etching carried out in a manner that the glass substrate is dipped in a bath filled with an etchant of strong acid etching a surface of the glass substrate.
However, such a method of wet etching makes the uneven surface of the substrate since particles generated from the etching process sticks to the substrate. Moreover, if the supply of the etchant fails to be controlled, the glass substrate is etched in part to generate the failure caused by the difference between the etched and non-etched portions.
In order to overcome such problems, a supply flow of an etchant is controlled using an etching apparatus equipped with a sensor enabling to sense the supply flow of the etchant.
An etching apparatus according to a related art is explained by referring to the attached drawings as follows.
FIG. 1 illustrates a schematic cross-sectional view of an etching apparatus according to a related art.
Referring to FIG. 1, an etching apparatus according to a related art includes an etching bath 1 having an etchant, a bubble plate 3 installed at a lower side inside the etching bath 1 to generate bubbles by a gas or an air supplied from outside to remove particles on a surface of a substrate which is being etched, a porous plate 5 installed on the bubble plate 3 to support a glass substrate (not shown in the drawing) to be etched, a supply pipe 15 supplying the bubble plate 3 with the air or the gas (N2), a buffer tank 13 discharging and filtering the etchant used for etching from the etching bath 1 through an etchant discharging pipe 11 for temporary storage, a deionized water supply unit 17 supplying deionized water, an undiluted etchant supply unit 19 supplying an undiluted etchant, an etchant supply tank 9 supplied with the deionized water and the undiluted etchant by the deionized water and the undiluted etchant supply units 17 and 19 and mixing the supplied deionized water and crude etchant with each other to supply the etching bath 1 with the etchant having a predetermined concentration through an etchant supply pipe 7, and an etchant detecting sensor 21 installed at an upper side of an inner wall of the etching bath 1 to detect a level of the etchant supplied to the etching bath 1.
In this case, the etchant supply tank 9 mixes the etchant using the deionized water supplied by the deionized water supply unit 17 and the undiluted etchant(ex. HF) supplied by the undiluted etchant supply unit 19, or is supplied with the etchant, which is recycled after completion of etching, from the buffer tank 13, to make the etchant having the predetermined concentration to be sent to the etching bath 1.
A plurality of glass substrate(not shown in the drawing) that will be etched are stood straight on the porous plate 5 with a predetermined interval from each other, and are dipped in the etchant filling the etching bath 1 for etching. Bubbles are generated through the bubble plate 3 and the etchant circulates uniformly by the bubbles. Thus, the glass substrates can be etched evenly. And, the bubbles detach the particles caused by the etching process from surfaces of the substrates.
Moreover, a guard 2 is formed on the inner wall of the etching bath 1 to protect the etchant detect sensor 21, and has a structure that front and rear sides in the drawing are open. If the etchant is supplied over a predetermined level, the etchant is put inside the guard 2.
In this case, when the etchant supplied from the etchant supply tank 9 to the etching bath 1 is supplied to the amount that the glass substrates are dipped in the etchant in part, the glass substrates fail to be etched uniformly but the portions of the glass substrates dipped in the etchant are etched only, whereby etch failure occurs. Hence, the etchant should be supplied to the level enabling to have the glass substrates dipped in the etchant entirely.
Therefore, it is able to control the supply of the etchant to the etching bath 1 stably using the etchant detect sensor 21 installed at the upper inner wall of the etching bath 1 before the etch is carried out. Moreover, it is also able to check the discharged state when the etchant is drained from the etching bath 1 after the completion of the etch.
Namely, the etchant detect sensor 21 according to the related art is a level sensor using an air pressure difference according to height of the etchant and the nitrogen gas (N2) supplied regularly, and includes, as shown in FIG. 2, a magnetic valve 22 controlling a supply of a nitrogen gas for constant pressures of three tubes by receiving a nitrogen gas (N2) of low pressure from a portion of the air supply pipe (‘15’ in FIG. 1), a plurality of nitrogen pressure difference sensors 23a, 23b, and 23c detecting a pressure difference of the nitrogen gas cut off by an etchant 25 supplied inside an etching bath by having the nitrogen gas flow, and “L(low)”, “H(high)”, and “HH(high high)” nitrogen tubes 24a, 24b, and 24c receiving the nitrogen gas at low pressure to discharge the nitrogen gas in accordance with height.
Operation of the above-constituted nitrogen pressure difference sensor is explained in detail as follows.
First of all, when the etchant 25 is supplied inside the etching bath 1 for etching the glass substrate, the etching apparatus according to the related art detects that the nitrogen gas fails to be discharged since the “L” nitrogen tube 24a of the etchant detect sensor is blocked by the etchant having been supplied over a predetermined level, thereby recognizing that the etchant is being supplied inside the etching bath 1. The etching apparatus keeps supplying the etchant even if the nitrogen gas is unable to be discharged due to the blocked “L” nitrogen tube 24a, and detects that the etching bath 1 is full of the etchant since the nitrogen gas is discharged no more due to the blocked “HH” nitrogen tube 24c, thereby stopping the supply of the etchant.
Subsequently, the nitrogen gas is put in the bubble plate 3 from the air supply pipe 15 to generate bubbles, whereby an etching process of the glass substrates is carried out normally.
In this case, the guard 2 protects the etchant detect sensor 21 from the bubbles generated from the etchant, whereby the etchant maintains a horizontal level. The etching process is performed normally when the nitrogen gas is discharged through the “HH” or “H” nitrogen tubes 24c or 24b. Yet, etching failure may occur when the nitrogen gas is discharged through the “L” nitrogen tube 24a.
Finally, when the etchant 25 is drained from the etching bath 1 after the completion of etching the glass substrate, the level of the etchant is lowered. Hence, the etching apparatus according to the related art recognizes that the etchant is normally drained since the nitrogen gas is discharged through the “L(low)”, “H(high)”, and “HH(high high)” nitrogen tubes 24a, 24b, and 24c, in order.
Unfortunately, the etching apparatus according to the related art has the following problems or disadvantages.
First of all, as the etching process is repeated, sludge as precipitates of the glass etched by the etchant blocks at least one of the “L”, “H”, and “HH” nitrogen tubes of the etchant detect sensor to perform the supply and discharge of the etchant abnormally. Hence, the etching apparatus according to the related art can cause failure of the etching process.
Secondly, when the “L” nitrogen tube is blocked, as shown at 26 in FIG. 2, a cleaning process for cleaning the glass substrate with deionized water is carried out under the circumstance that the drain of the etchant is not completed. Hence, the etching apparatus according to the related art causes degradation of the cleaning work since the deionized water as the cleaning material is mingled with the etchant.
Finally, the etching apparatus according to the related art consumes cost and time for replacement of the components or periodical cleaning works to prevent outlets of the “L”, “H”, and “HH” nitrogen tubes from being blocked by the sludge, thereby reducing productivity. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The present invention relates to a semiconductor integrated circuit having a test mode.
2. Description of the Related Art
As a semiconductor integrated circuit having a test mode, for example, a technique disclosed in Japanese Unexamined Patent Application Publication No. Hei 2000-243797 is known. This semiconductor integrated circuit shifts to the test mode when a test command is inputted a plurality of times in a normal operation mode. Therefore, the semiconductor integrated circuit is prevented from shifting to the test mode accidentally in normal operation.
However, for example, when a plurality of tests are executed after the semiconductor integrated circuit is fabricated, it is necessary to input a command signal a plurality of times for each test. It is also necessary to input the command signal a plurality of times to shift an operation mode in the semiconductor integrated circuit from the test mode to the normal operation mode after each test is terminated. Hence, there is a problem that, when a plurality of the tests are executed successively, the command signal needs to be inputted many times, thereby increasing the test time. | {
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The present invention relates to a rotating frame animal trap. More particularly, the present invention relates to improvements in the frame design of the rotating frame type of trap. By a rotating frame animal trap is meant a trap which comprises a pair of similar frames pivotally connected at adjacent ends for relative rotation on a common axis so as to form by their sides two pairs of co-acting jaws.
One drawback in the use of such traps arises from the fact that the clamping force of the trap increases as the trap closes, and reaches a maximum as the actuator rings reach the ends of their runs and bear against the extremities of adjacent ends of the trap frames. Thus, when large or bulky-bodied animals are caught in the trap, their body size may prevent the jaws of the trap from closing enough so that the actuator arms can expand sufficiently about these adjacent ends and thus develop enough leverage and clamping force to quickly kill the animal. It can therefore be seen that the humane efficiency of the trap, i.e., the ability of the trap to kill any desired animal passing through it, large or small, so that the animal, when caught by the trap, will be killed as quickly as possible, is adversely affected insofar as bulky animals are concerned. Previous solutions to this problem are described, for example, in U.S. Pat. Nos. 3,760,531 and 3,971,155.
By the present invention, there is provided an improved rotating frame animal trap, having features which provide for increasing the force of the jaws so as to kill the trapped animal as quickly as possible, thus providing a trap which is more humane. It should be pointed out that the trap of the present invention is not more effective for large bulky animals, if they fall outside the range of high forces, but it is more effective for animals whose neck is within the range of high forces. The trapper determines the type of target animal by means of trap placement, and selects a trap of appropriate size.
The animal trap of the present invention includes, as general features, two similar frames each formed of round wire stock and having opposite side portions serving as jaws and connecting end portions. The frames are pivotally connected through adjacent end portions for relative rotation between set and closed positions about a common axis. Trigger means is provided for releasably maintaining the trap in a set position. An actuator is provided for rapidly and forcefully effecting such rotation upon release of the trigger. The actuator includes two arms which are spring biased at one end so that the other ends, if unobstructed, would move to a distance substantially greater than the width of the frame ends. Each arm of the actuator terminates in a ring respectively adapted to encircle adjacent ends of the frames on opposite sides of the axis.
The improvement of the present invention resides in constructing the trap frame members in a manner that results in connecting end portions thereof being parallel or nearly parallel to each other when in the closed position, and with the connecting end portions, when in an upright position, being located at an angle relative to the vertical of from about 5 to about 10 degrees. It has been found that the more clearly parallel the adjacent connecting end portions of the jaws are, and hence the smaller the angle between said connecting end portions and the vertical, the greater will be for force achieved by the jaws of the trap during closure. | {
"pile_set_name": "USPTO Backgrounds"
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The present invention relates to a two-cycle engine with a scavenge pump for feeding air into the engine and with a direct fuel injection system, and more particularly to a system for controlling the timing of opening and closing scavenge and exhaust rotary valves in the engine.
In two-cycle engines, each cycle is completed with one revolution of a crankshaft so that self-intake operation into a cylinder is not carried out. For this reason, a method is used wherein air is induced into a crankcase with the use of vacuum generated in a crankcase while a piston is in its upward strokes, and wherein intake into the cylinder is carried out through a scavenge port by increased pressure in the crankcase due to downward strokes of the piston while the gases produced after combustion in the cylinder is forced out of the cylinder by the scavenging flow of the intake gas. Further, for control depending upon the load on the engine, a throttle valve is provided in an intake system, and the amount of intake is adjusted by varying the degree of opening of the throttle valve.
In such a known system, the scavenging flow tends to be insufficient under low load condition due to a small amount of intake, and this causes misfiring with resultant unstable operation of the engine. Moreover, it is difficult to obtain a smooth torque characteristic of the engine in accordance with operating conditions so that much fuel is consumed and exhaust gas is degraded. Furthermore, there is a limit to increase in the scavenging ability of the engine with such a type of scavenging system using the crankcase pressure. This means that it is difficult to obtain a sufficiently increased torque of the engine under high load.
Under such circumstances, it has been desired to obtain increased scavenging ability and to reduce flow of the fuel through the cylinder. With a view to realizing the above, it has been proposed to use a scavenge pump for increasing the scavenging pressure and to inject the fuel directly into the cylinder chamber by means of a fuel injector so as to prevent the unburnt fuel from flowing through the cylinder during the scavenging.
A two-cycle engine provided with a scavenge pump and a fuel injector is disclosed in, for example, Japanese Utility Model Laid-Open (unexamined) Publication No. 62-97,229. The two-cycle engine disclosed in this publication is provided with overhead valves as in the case of a four-cycle engine and with a supercharger in an intake system and an exhaust blower in the exhaust system. The supercharger and/or the exhaust blower are operated depending upon the operating condition of the engine.
In the known two-cycle engine described above, low scavenging efficiency accompanied by the overhead valves must be compensated for by the supercharger and the exhaust blower, so that the engine necessarily has a complicated construction as well as increased loss of power for driving auxiliary mechanisms of the engine. Furthermore, in the known engine, timing of opening and closing the intake and exhaust valves is always fixed, so that it is not possible to increase the scavenging efficiency and the output of the engine in accordance with the engine operating conditions. | {
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This invention relates to an assembly for collecting a liquid sample from a patient, such as a blood sample. More particularly, this invention relates to a needle assembly for collecting sequentially multiple liquid samples from such a patient. The device of the invention utilizes a receiving chamber with walls which are translucent or transparent for visually indicating whether or not proper access to the source of the sample in question has been achieved. Moreover, the housing or chamber which receives the sample incorporates therein a porous filter which filter is comprised of a material which provides, simultaneously, a liquid barrier for the sample received in the housing, and a gas displacement discharge passage for gas displaced by the liquid sample received in the chamber.
The filter in the housing is positioned in such a way that it extends from the chamber to an exit point for the discharge of gas out of the housing chamber, which exit point may be covered by the cooperative engagement of the flange of the rubber sleeve or valve means which extends over the discharge opening of the negative pressure cannula during periods when a sample is not being discharged therefrom into an evacuated tube. Subsequently, when a liquid sample is to be discharged into an evacuated tube placed over the negative pressure cannula, the stopper for the tube engages the sleeve in a conventional manner. The negative pressure point of the negative pressure cannula passes through the stopper of the evacuated tube and the stopper moves along the negative pressure cannula toward the housing. In doing so, the point of the negative pressure cannula pierces the sleeve, and causes the sleeve to collapse and move toward the adjacent housing face. Thus, the flange of the sleeve is caused to engage the housing face, closing off the exit end of the filter device. For this reason, when a sample is being collected from the housing chamber into an evacuated tube, no air is allowed to pass through the filter from outside into the chamber.
Once the evacuated tube is withdrawn from the negative pressure cannula, the sleeve moves outwardly to reseal the discharge opening of the negative pressure cannula and the sample chamber in the assembly housing until the next evacuated tube is inserted into the assembly. Thus, with the sequential application of a series of evacuated tubes, the tubes move the sleeve out of engagement with the negative pressure discharge opening or point of the negative pressure cannula, and cause the flange of the sleeve to engage the exit opening of the filter to prevent any air passing into the sample chamber.
As discussed above, it is desirable to provide a mechanism whereby the user of such a needle assembly can be informed when the intravenous needle has penetrated the vein of the patient for collecting a blood sample. Many times, in collecting blood from a patient, it is difficult to locate the vein, or for other reasons blood flow into the collecting device is not adequate. In those instances, it is advantageous to be able to make a quick determination that entry into the vein has been made and that blood is flowing into the needle assembly.
Once this determination has been made and the vein entry achieved, the evacuated blood collection containers can be inserted, sequentially, as discussed above, into the collection assembly in accordance with well known techniques of collecting blood samples during a single collection procedure. Thus, by utilizing a translucent or transparent chamber, with the assembly of the invention herein, the fact that blood flow has been obtained is quickly realized simply by the user visually noting blood collecting in the housing chamber of the assembly of the invention here. Furthermore, as discussed above, with the utilization of the porous filter in the housing wall, the filter allows for displacement of the air from the housing chamber so as to allow room for receiving the blood sample being collected.
A prior art device which recognizes the utilization of a porous material for providing a venting for displaced air during receiving a blood sample is taught in U.S. Pat. No. 4,207,870, issued June 17, 1980. That assembly requires a separate one-way valve construction which opens and allows blood to travel from the vein of the patient and through the housing and into an evacuated container. Other related applications include co-pending U.S. applications Ser. No. 160,781 filed June 18, 1980, now U.S. Pat. No. 4,340,068, issued July 20, 1982, Ser. No. 284,894 filed July 20, 1981 and Ser. No. 311,494 filed Oct. 15, 1981.
Other objects and advantages of this invention will be apparent from the following description, the accompanying drawings and the appended claims. | {
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1. Field of the Invention
The present invention relates generally to laser machining. More specifically, it pertains to a pulsed laser ablation method of films from the surface of a semi-conducting wafer, printed circuit board or a hybrid substrate and/or to the substrate without affecting the material adjacent to the ablation zone.
2. State of Technology
In defining films on electronic circuits, the present state-of-the-art process is to use a physical mask to define the metal or dielectric film by photolithographic processes. However, the use of such physical masks can produce non-uniformities in the desired structures of the films due to: undercutting of the metal films by required acid etching techniques, the requirement of a lift-off process because the dielectric film cannot be etched, films that require heating may result in a damaged photo-resist, and turn-around times for producing the physical mask being up to several weeks.
However, lasers may be utilized to overcome such problems and define such films on electronic circuits. Such lasers have previously been used to machine or cut a target comprised of a rigid material, such as metals, wood, rubber or plastics. Lasers machine or cut such materials by inducing a breakdown of the material through chemical and physical breakdown, vaporization, and ablation. Pulsed lasers have been utilized to selectively ablate material from such targets by outputting pulses of light having pulse durations of less than nanoseconds.
Accordingly, there is a need in industry for utilizing pulsed lasers, in particular, ultra-short pulsed lasers having temporal pulse durations of less than about 1 picosecond to define features on films arranged on substrates. | {
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The present invention relates to methods and pharmaceutical compositions for An treating and preventing alopecia in a a patient in need thereof.
Hair growth is not continuous, but comprises alternating periods of growth (xe2x80x9canagenxe2x80x9d), regression (xe2x80x9ccategenxe2x80x9d) and rest (xe2x80x9ctelogenxe2x80x9d). (U.S. Pat. No. 5,055,456, incorporated by reference herein in its entirety) In the scalp, the anagen phase lasts about 6 years and the telogen phase about 4 months. The growth of scalp hair is not synchronous, and the rate of growth is about 0.4 mm per day. About 90 percent of the more than 100,000 scalp hairs are growing (anagen), so that 50 to 100 hairs are shed daily as they are pushed out at the onset of a new hair cycle.
The hair follicle is an epidermal appendage, the lower part of which undergoes cycles of growth and degeneration. (U.S. Pat. No. 5,556,783, incorporated by reference herein in its entirety) During the anagen (the growing phase) of the hair cycle, matrix keratinocytes located in the bulb region grow vigorously, generating cells that differentiate into several distinct hair components including the medulla, cortex and inner root sheath. During catagen, keratinocytes of the lower follicle below the bulge region (the attachment site of the arrector pili muscle) degenerate and the dermal papilla cells (DP; a group of specialized mesenchymal cells) aggregate and become encapsulated by a connective tissue sheath. Through the contraction of this sheath, the DP aggregate ascends and becomes attached to the bottom of the upper (permanent) portion of the follicle (telogen or the resting phase). Finally, a new epithelial growth originates from the bottom of the bulge area; this downgrowth pushes the DP away and reforms a growing bulb.
The in vitro growth potential of different subpopulations of follicular epithelial cells have been studied. (U.S. Pat. No. 5,556,783) Keratinocytes of different portions of human scalp follicles were isolated by microdissection followed by trypsinization and propagated in the presence of 3T3 feeder cells. The results indicate that the upper follicle contains keratinocytes that have in vitro proliferative potential that is significantly higher than those of the lower follicle, the bulb, the sebaceous gland and the epidermis.
Alopecia (hair loss) is a common condition that results from diverse causes. For example, adrenergic alopecia (common baldness) is seen in the vast majority of adult males and is considered physiologic and part of the aging process. (U.S. Pat. No. 5,616,471, incorporated by reference herein in its entirety) Besides the loss of hair, the length and diameter of each hair will be reduced in the adjacent areas even though the follicles remain intact.
Telogen effluvium is a transient, reversible, diffuse shedding of hair in which a high percentage of hair follicles enter the telogen phase prematurely as a result of physical or mental illness. Among the most important factors incriminated are childbirth, high fever, hemorrhage, sudden starvation, accidental or surgical trauma, severe emotional stress, and certain drugs.
Alopecia areata is an immunologic alopecia characterized by the abrupt onset of sharply defined areas of hair loss. In the most severe cases, the scalp will develop total hair loss (alopecia totalis) or the hair loss will involve the whole body surface (alopecia universalis). Most of the patients will run an unpredictable and relapsing course with multiple episodes of hair loss and regrowth. Only about 20 to 30 percent will have a single reversible episode. Regrowth of hair is common within several months, but in many instances is not complete, and relapses are common. Alopecia areata may be associated with autoimmune diseases such as vitiligo, pernicious anemia, collagen disease, and endocrinopathies.
Traumatic alopecia is induced by physical trauma, of which the two most important groups, from the therapeutic standpoint are trichotillomania and alopecia resulting from cosmetic procedures or improper hair care. Trichotillomania is a compulsive habit in which the individual repeatedly pulls or breaks off his or her own hair in a partially conscious state similar to thumb sucking or nail biting. Traumatic alopecia from cosmetic procedures is done consciously in ill-advised individuals and is almost exclusively seen among females. Sometimes this type of alopecia is associated with folliculitis induced by the occlusive effect of the oily cosmetics used in the procedure.
Anagen effluvium is a temporary alopecia caused by the inhibition of mitosis in the hair papilla by certain cytotoxic drugs, leading to constriction of the hair shaft or to complete failure of hair formation. In particular, alopecia frequently occurs in cancer patients who are treated with chemotherapeutic drugs such as cyclophosphamide (CY) and/or irradiation. U.S. Pat. No. 5,962,523 Such agents damage hair follicles which contain mitotically active hair-producing cells. Such damage may cause abnormally slow growth of the hair or may lead to frank loss. While various attempts have been made to protect against alopecia or abnormal rates of hair growth during such treatments, there remains a need for an agent that prevents damage to hair follicles in a safe and effective manner.
Alopecia may also result from nutritional deficiencies and metabolic defects. Caloric deprivation must be very severe to produce hair loss. Increased shedding sometimes occurs after marked weight loss for obesity. Anemia, diabetes, hyper- and hypovitaminosis, and zinc deficiency may also lead to alopecia.
Treatments for androgenetic alopecia have been ineffective in inducing regrowth. The use of cyclic estrogen therapy in females with an estrogen-dominant contraceptive or topical estrogen has been advocated to reduce the rate of hair loss, but results are not impressive. The claim that topical testosterone induces the growth of terminal hairs in bald scalp of males has not been confirmed.
There have been some indications that minoxidil (ROGAINE(copyright)., Upjohn), a potent vasodilator, has been effective in causing scalp hair regrowth in patients with androgenetic alopecia, but the results have been mixed.
U.S. Pat. 5,962,523 discloses the use of butyric acid or butyric acid derivatives to protect against hair damage or loss in a mammal as described herein.
Thus, there remains a need in the art for methods of treating and preventing the various types of alopecia.
In one aspect, the present invention provides methods and kits for treating or preventing alopecia by contacting the cells with angiotensinogen, angiotensin I (AI), AI analogues, AI fragments and analogues thereof, angiotensin II (AII), AII analogues, AII fragments or analogues thereof, ACE inhibitors, or AII AT2 type 2 receptor agonists, either alone or in combination with other alopecia-inhibiting compounds. | {
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Certain types of commodity and/or industrial items can be packaged by placing the desired product(s) in a covering material and then applying a closure clip or clips to end portions of the covering material to secure the product(s) therein. For non-flowable piece goods, the piece goods can be held individually in a respective clipped package, or as a group of goods in a single package. The covering material can be any suitable material, typically a casing and/or netting material.
Generally described, when packaging a piece good product in netting, the product is manually pushed through a netting chute. The product can include, by way of example, a non-flowable semi-solid and/or solid object such as a meat product including whole or half hams, turkey, chicken, and the like. The netting chute holds a length of a netting sleeve over the exterior thereof. A first downstream end portion of the netting is typically closed using a first clip. As the product exits the netting chute, it is covered with the netting. An operator can then orient the product inside the netting between the discharge end of the chute and the clipped first end portion of the netting. The operator can then pull the netting so that the netting is held relatively tight (typically stretched or in tension) over the product. The operator then uses his/her hands to compress or gather the open end of the netting (upstream of the product) and then manually applies a clip to the netting, typically using a Tipper Tie® double clipper apparatus. A clip attachment apparatus or “clippers” are well known to those of skill in the art and include those available from Tipper Tie, Inc., of Apex, N.C., including product numbers Z 3214, Z 3202, and Z 3200. Examples of clip attachment apparatus and/or packaging apparatus are descried in U.S. Pat. Nos. 3,389,533; 3,499,259; 4,683,700; and 5,161,347, the contents of which are hereby incorporated by reference as if recited in full herein.
The double clipper concurrently applies two clips to the netting proximate the open (upstream) end of the package. One clip defines the first end portion of the next package and the other defines the trailing or second end portion of the package then being closed. A cutting mechanism incorporated in the clipper apparatus can sever the two packages before the enclosed package is removed from the clipper apparatus. U.S. Pat. No. 4,766,713 describes a double clipper apparatus used to apply two clips to a casing covering. U.S. Pat. No. 5,495,701 proposes a clipper with a clip attachment mechanism configured to selectively fasten a single clip or two clips simultaneously. The mechanism has two punches, one of which is driven directly by a pneumatic cylinder and the other of which is connected to the first punch using a pin and key assembly. The pin and key assembly allows the punches to be coupled or decoupled to the pneumatic cylinder drive to apply one single clip or two clips simultaneously. U.S. Pat. No. 5,586,424 proposes an apparatus for movement of U-shaped clips along a rail. The apparatus includes a clip feed for advancing clips on a guide rail and the arm is reciprocally driven by a piston and cylinder arrangement. The contents of each of these patents are hereby incorporated by reference as if recited in full herein. | {
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Future transportation is widely believed to be based on a hydrogen economy. Using fuel cells, cars and trucks will no longer burn petroleum and will no longer emit CO2 on the streets since they will use hydrogen as the fuel and the only byproduct is water. However, the reforming process, the main process that is used in today's hydrogen production, still uses petroleum-based products as the raw material and still emits large amounts of CO2. To reduce our society's reliance on petroleum based products and to avoid the emission of CO2 that causes global warming, a renewable method of generating hydrogen must be developed. An electrolysis process using only sunlight and water is considered to be a top choice for hydrogen generation. Such hydrogen fuel is ideal for proton exchange membrane fuel cell (PEMFC) applications since it contains extremely low concentrations of carbon monoxide, which is poisonous to platinum catalysts in PEM fuel cells. However, indirect photo-electrolysis, in which the photovoltaic cells and electrodes are separated and connected electrically using external wires, is not cost-effective. An integrated photoelectrochemical cell (PEC) offers the potential to generate hydrogen renewably and cost effectively.
Several prior inventions and publications have disclosed designs for photoelectrochemical cells. U.S. Pat. No. 4,090,933 (Nozik), U.S. Pat. No. 4,144,147 (Jarrett et al.), U.S. Pat. No. 4,236,984 (Grantham), U.S. Pat. No. 4,544,470 (Hetrick), U.S. Pat. No. 4,310,405 (Heller), U.S. Pat. No. 4,628,013 (Figard et al.), U.S. Pat. No. 4,650,554 (Gordon), U.S. Pat. No. 4,656,103 (Reichman et al.), U.S. Pat. No. 5,019,227 (White et al.), U.S. Pat. No. 6,471,850 (Shiepe et al.), U.S. Pat. No. 6,361,660 (Goldstein), U.S. Pat. No. 6,471,834 (Roe et al.).
J. R. Bolton “Solar photoproduction of hydrogen: a review”, Solar Energy, 57, 37 (1996).
S. S. Kocha, D. Montgomery, M. W. Peterson, J. A. Turner, “Photoelectrochemical decomposition of water utilizing monolithic tandem cells”, Solar Energy Materials & Solar Cells, 52, 389 (1998).
S. Licht, “Efficient solar generation of hydrogen fuel—a fundamental analysis”, Electrochemistry Communications 4, 790 (2002).
P. K. Shukla, R. K. Karn, A. K. Singh, O. N. Srivastava, “Studies on PV assisted PEC solar cells for hydrogen production through photoelectrolysis of water”, Int. J. of Hydrogen Energy, 27, 135 (2002).
X. Gao, S. Kocha, A. Frank, J. A. Turner, “Photoelectrochemical decomposition of water using modified monolithic tandem cells”, In. J. of Hydrogen Energy, 24, 319 (1999).
R. E. Rocheleau and E. L. Miller, “Photoelectrochemical production of hydrogen: Engineering loss analysis”, Int. J. Hydrogen Energy, 22, 771 (1997).
However, the prior art devices and methods described and disclosed in these above mentioned patents and publications have at least one of the following shortcomings: the photovoltaic cell does not generate sufficient voltage to split water, the photovoltaic cell needs an external electrical bias for the electrolysis, the photovoltaic device will not survive for extended use in the electrolyte due to inappropriate protection, the photovoltaic device cannot be fabricated using low-cost methods, and the photovoltaic device does not have potential for high conversion efficiency.
Therefore, there is a compelling and crucial need in the art for an efficient PEC device that produces hydrogen from water under radiation, does not require external bias due to sufficient voltage, and can be made at low cost. | {
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A PON (Passive Optical Network) is one of configurations for implementing FTTH (Fiber To The Home) that provides each home with network access service through an optical fiber. A feature of the PON lies in that optical access service can be provided at low cost by making communication with a part of the optical fiber, which connects between a home-side device (an optical network unit (ONU)) and a subscriber line terminal (an optical line terminal (OLT)), being commonly used.
In a network system including the FTTH, a new function is frequently required to be added and a function to solve a problem is frequently required. A method for implementing such functions is to download a software program to be executed by a CPU (Central Processing Unit) in a network device, or to download design data of an FPGA (Field Programmable Gate Array) in the network device. It should be noted that a term “firmware” herein includes a program code to be executed by a CPU provided in a communication device (irrespective of the OLT and the ONU), as well as a configuration code of the FPGA.
For example, Patent Document 1 (Japanese Patent Laying-Open No. 2010-252176) discloses a communication system configured such that an OLT broadcasts, to a plurality of ONUs, data that should be downloaded by the plurality of ONUs. The data that should be downloaded by the plurality of ONUs can include firmware for updating firmware embedded in each of the plurality of ONUs. According to the above-described configuration, the download by the plurality of ONUs connected to the PON can be done in a short time. | {
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RNA interference or “RNAi” is a term initially coined by Fire and co-workers to describe the observation that double-stranded RNA (dsRNA) can block gene expression when it is introduced into worms (Fire et al., Nature 391:806-811, 1998). Short dsRNA directs gene-specific, post-transcriptional silencing in many organisms, including vertebrates, and has provided a new tool for studying gene function. This technology has been reviewed numerous times recently, see, for example Novina, C.D:, and Sharp, P., Nature 2004, 430:161, and Sandy, P., et al., Biotechniques 2005, 39:215, hereby incorporated by reference.
Influenza is one of the most widely spread infections worldwide. It can be deadly: an estimated 20 to 40 million people died during the 1918 influenza A virus pandemic. In the United States between 20 and 40 thousand people die from influenza A virus infection or its complications each year. During epidemics the number of influenza related hospitalizations may reach over 300,000 in a single winter season.
Several properties contribute to the epidemiological success of influenza virus. First, it is spread easily from person to person by aerosol (droplet infection). Second, small changes in influenza virus antigens are frequent (antigenic drift) so that the virus readily escapes protective immunity induced by a previous exposure to a different variant of the virus. Third, new strains of influenza virus can be easily generated by reassortment or mixing of genetic material between different strains (antigenic shift). In the case of influenza A virus, such mixing can occur between subtypes or strains that affect different species. The 1918 pandemic is thought to have been caused by a hybrid strain of virus derived from reassortment between a swine and a human influenza A virus. At present, there is a spreading concern about the potential emergence of novel influenza strains infective to humans, particularly from avian influenza variants, and more particularly from strain H5N1, by mixing in humans concurrently exposed to human and avian influenza virus. The close contact between agricultural birds and their human breeders familiar in most asian societies has experts convinced that it is not a question of whether but only when such a mixed strain will arise. A world-wide pandemic could swiftly ensue, with even graver consequences than in 1918.
Despite intensive efforts, there is still no effective therapy for influenza virus infection and existing vaccines are limited in value in part because of the properties of antigenic shift and drift described above. For these reasons, global surveillance of influenza A virus has been underway for many years, and the National Institutes of Health designates it as one of the top priority pathogens for biodefense. Although current vaccines based upon inactivated virus are able to prevent illness in approximately 70-80% of healthy individuals under age 65, this percentage is far lower in the elderly or immunocompromised. In addition, the expense and potential side effects associated with vaccine administration make this approach less than optimal. Although the antiviral drugs currently approved in the United States for treatment and/or prophylaxis of influenza are helpful, their use is limited due to concerns about side effects, compliance, and possible emergence of resistant strains.
US patent application 20040242518 and corresponding WO 04/028471, both filed Sep. 29, 2003, propose a limited number of RNAi agents for the treatment of influenza. Their efficacy in humans is not disclosed.
Therefore, there still remains a need for the development of effective therapies for the treatment and prevention of influenza infection in humans and animals, and particularly for therapies with high efficiency that allow the targeting of a broad range of influenza subtypes. One prerequisite for high efficiency is that the active ingredient is not degraded quickly in a physiological environment. | {
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Many enterprises employ an interactive voice response (IVR) system that handles calls from telecommunications terminals. An interactive voice response system typically presents a hierarchy of menus to the caller, and prompts the caller for input to navigate the menus and to supply information to the IVR system. For example, a caller might touch the “3” key of his terminal's keypad, or say the word “three”, to choose the third option in a menu. Similarly, a caller might specify his bank account number to the interactive voice response system by inputting the digits via the keypad, or by saying the digits. In many interactive voice response systems the caller can connect to a person in the enterprise by either selecting an appropriate menu option, or by entering the telephone extension associated with that person.
FIG. 1 depicts telecommunications system 100 in accordance with the prior art. Telecommunications system 100 comprises telecommunications network 105, private branch exchange (PBX) 110, and interactive voice response system 120, interconnected as shown.
Telecommunications network 105 is a network such as the Public Switched Telephone Network [PSTN], the Internet, etc. that carries a call from a telecommunications terminal (e.g., a telephone, a personal digital assistant [PDA], etc.) to private branch exchange 110. A call might be a conventional voice telephone call, a text-based instant messaging (IM) session, a Voice over Internet Protocol (VoIP) call, etc.
Private branch exchange (PBX) 110 receives incoming calls from telecommunications network 105 and directs the calls to interactive voice response (IVR) system 120 or to one of a plurality of telecommunications terminals within the enterprise, depending on how private branch exchange 110 is programmed or configured. For example, in an enterprise call center, private branch exchange 110 might comprise logic for routing calls to service agents' terminals based on criteria such as how busy various service agents have been in a recent time interval, the telephone number called, and so forth. In addition, private branch exchange 110 might be programmed or configured so that an incoming call is initially routed to interactive voice response (IVR) system 120, and, based on caller input to IVR system 120, subsequently redirected back to PBX 110 for routing to an appropriate telecommunications terminal within the enterprise. Private branch exchange (PBX) 110 also receives outbound signals from telecommunications terminals within the enterprise and from interactive voice response (IVR) system 120, and transmits the signals on to telecommunications network 105 for delivery to a caller's terminal.
Interactive voice response (IVR) system 120 is a data-processing system that presents one or more menus to a caller and receives caller input (e.g., speech signals, keypad input, etc.), as described above, via private branch exchange 110. Interactive voice response system (IVR) 120 is typically programmable and performs its tasks by executing one or more instances of an IVR system application. An IVR system application typically comprises one or more scripts that specify what speech is generated by interactive voice response system 120, what input to collect from the caller, and what actions to take in response to caller input. For example, an IVR system application might comprise a top-level script that presents a main menu to the caller, and additional scripts that correspond to each of the menu options (e.g., a script for reviewing bank account balances, a script for making a transfer of funds between accounts, etc.).
A popular language for such scripts is the Voice extensible Markup Language (abbreviated VoiceXML or VXML). The Voice extensible Markup Language is an application of the extensible Markup Language, abbreviated XML, which enables the creation of customized tags for defining, transmitting, validating, and interpretation of data between two applications, organizations, etc. The Voice extensible Markup Language enables dialogs that feature synthesized speech, digitized audio, recognition of spoken and keyed input, recording of spoken input, and telephony. A primary objective of VXML is to bring the advantages of web-based development and content delivery to interactive voice response system applications.
FIG. 2 depicts an exemplary Voice extensible Markup Language (VXML) script (also known as a VXML document or page), in accordance with the prior art. The VXML script, when executed by interactive voice response system 120, presents a menu with three options; the first option is for transferring the call to the sales department, the second option is for transferring the call to the marketing department, and the third option is for transferring the call to the customer support department. Audio content (in particular, synthesized speech) that corresponds to text between the <prompt> and </prompt> tags is generated by interactive voice response system 120 and transmitted to the caller.
The VXML script of FIG. 2 also comprises two event handlers. An event can be generated when a caller provides input (e.g., speech, keypad entry, etc.) in response to a prompt from the VXML script, or when there is a prompt timeout (i.e., the caller does not provide any input for a specified time period after a prompt). The first event handler of the VXML script catches and processes events of type telephone.disconnected.hangup, which are generated when a caller hangs up, and the second event handler catches and processes events of type nomatch, which are generated when a caller's input does not match any of a menu's choices.
Another popular standard for IVR system application scripts is Speech Application Language Tags (SALT). FIG. 3 depicts an exemplary XML script of the prior art that contains Speech Application Language Tags (SALT) and provides functionality similar to the VXML script of FIG. 2. | {
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The present invention relates to a semiconductor device and a manufacturing method thereof, and in particular, to a semiconductor device having a metal resistive element and a manufacturing method thereof.
Microcontroller products and oscillators have been structured separately from each other before, but in recent years, oscillators are embedded in microcontroller chips in order to reduce layout areas and cost, etc. In order to embed an oscillator in a microcontroller chip, it is needed to output stable oscillating frequencies under any environment (voltage, temperature), and it is required to achieve, for example, 40 MHz±1% as a target accuracy in a high-speed OCO (On Chip Oscillator) circuit of a microcontroller product.
In order to achieve the aforementioned target accuracy, it is desirable to adopt titanium nitride (TiN) in a resistive element for a constant current generation circuit in a high-speed OCO circuit that is an analog circuit of an oscillator. One reason why TiN is adopted is that, because a so-called piezo-resistance effect is not generated in TiN, a variation in resistance values, occurring due to the stress resulting from a piezo-resistance effect, is small. The accuracy in oscillating frequencies can be enhanced with a variation in resistance values being reduced. Another reason for this is that, because the temperature dependence of a resistance value in a circuit using TiN is appropriate in a silicon process, TiN is suitable for being used as a so-called barrier metal covering the upper and lower surfaces of wiring. Resistive elements using TiN are disclosed, for example, in Japanese Unexamined Patent Publication No. 2011-155192 (Patent Document 1) and Japanese Unexamined Patent Publication No. 2004-303908 (Patent Document 2). | {
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Colorectal cancer (CRC) is one of the most common cancer types in both men and women worldwide, with about 1.2 million new cases recorded annually. [1] The prognosis is highly dependent on the tumour stage at time of diagnosis. According to the American Joint Committee on Cancer (AJCC), the 5-year overall survival rate is 93%, 83%, 60% and 8% in stage I, II, III, and IV, respectively. [2] However, the prognosis for stage IIb patients (pT3-4, lymph node negative) is significantly lower (72%) than for those with stage IIIa (pT1-2, lymph node positive; 83%). [2]
Adjuvant chemotherapy significantly improves survival in among stage III CRC and is accepted as standard treatment of these patients. [3] The majority of stage II CRC patients are cured by surgery alone, but perforation of the tumour and few examined lymph nodes are associated with reduced survival, and are usually considered for adjuvant chemotherapy. A proportion of stage II patients without increased risk of relapse based on current clinical factors still develop relapse. One could consider treating all stage II CRC patients with adjuvant chemotherapy, but the effect of this has not been conclusive. [4-6]
This highlights the need for new biomarkers for more precise prediction of high-risk stage II patients, and consequently also improved individualized cancer care. | {
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The present invention pertains to the field of two-dimensional spatial light modulation.
Optics is playing a greater and wider role in the fields of electronics, telecommunications, signal processing, and data storage. Light beams are preferable over electrical signals because of their high bandwidth and propagation speed. Rather than using conventional electrical signals, optical based systems employ light beams to convey and process information. In optical based systems, a light source, such as a laser, is modulated to convey the desired information. By implementing digital or analog modulation, the light beam can be used in a wide variety of different applications. Chief among these applications has been the generation of visual displays, optical signal processing, optical digital computing, laser printing, and storage of digital information, etc.
Although lasers can be modulated at rather high frequencies, many applications require even higher data rates. In an effort to increase the data rate, some prior art optical systems have implemented multiple light beams. By processing these multiple light beams in parallel, the overall speed of the system can dramatically be enhanced. And depending on the particular application, the number of light beams can range from tens to perhaps several thousands.
The disadvantage to utilizing multiple light beams is that a separate light source was typically required to generate each of these beams. Not only do these additional generators significantly increase the cost, but they also impact the reliability of the overall system. Moreover, these multiple generators increases the size of the packaging several fold.
Furthermore, prior art light modulation schemes have typically concentrated on the number of modulator array elements, rather than the element or total array modulation rate. Not that waveguide and PLZT ceramic devices operate only in transverse mode, whereas pockels effect devices operate in either transverse or longitudinal modes.
Thus, there is a need in the art for a light beam multiplication apparatus and method, whereby a single or a few light sources can be used to effectively create multiple light beams, each independently modulatable. It would also be preferable if such an apparatus and method could achieve a high throughput rate by implementing a fast, electrically driven modulator element array, comprised of a multiplicity of part independent modulators through each of which passes a single light-beam. It is further most beneficial if each throughput light-beam is diffraction limited.
The present invention pertains to an apparatus and method for generating a two dimensional array of diffraction limited modulated light beams for use in optical fiber telecommunications, optical signal processing, optical digital computing, laser printing, optical recording, etc. Basically, a laser diode and a collimator are used to generate a single collimated light beam. This collimated light beam is passed through a two dimensional holographic beam splitter. Thereupon, the holographic beam splitter produces a two dimensional divergent array of diffraction limited collimated light beams. These light beams are then independently modulated by a matched two dimensional array of electrooptic modulator elements to produce a two dimensional array of modulated light beams. The modulator array can be comprised of discrete micro optical Pockels modulators, waveguide structures, or an array of ferroelectric modulators using either bulk materials or a thin film layer deposited on a substrate. The resulting two dimensional array of modulated light beams can then be sent on to a recording medium or to an input plane to a next process. | {
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1. Field of the Invention
This invention relates to new and improved catalysts for the production of vinyl acetate by reaction of ethylene, oxygen and acetic acid.
2. Background Information Including Description of Related Art
It is known to produce vinyl acetate by reaction of ethylene, oxygen and acetic acid using a catalyst consisting of palladium, gold, and copper supported on a carrier. While the process utilizing such a catalyst is capable of producing vinyl acetate at relatively high levels of productivity, any expedient which could possibly result in even greater productivity would be very desirable.
The following references may be considered material to the invention claimed herein.
U.S. Pat. Nos. 3,775,342 issued Nov. 27, 1973, and 3,822,308 issued Jul. 2, 1974, both to Kronig et al., each discloses a method of making vinyl acetate catalysts comprising treating a support simultaneously or successively with a solution A containing dissolved salts of noble metals such as palladium and gold and a solution B containing compounds able to react on the support with the noble metal salts to form water insoluble compounds, treating such water-insoluble compounds with a reducing agent to convert the water-insoluble noble metal compounds to the free metals, washing the catalyst to remove water-soluble compounds, and applying an alkali metal compound e.g. an alkali metal carboxylate before or after treatment with the reducing agent. Solution A can optionally also contain salts of other metals such as magnesium, calcium, barium and copper.
U.S. Pat. No. 5,332,710, issued Jul. 26, 1994, to Nicolau et al., discloses a method of preparing a catalyst usefull for the production of vinyl acetate by reaction of ethylene, oxygen and acetic acid, comprising impregnating a porous support with water soluble salts of palladium and gold, fixing the palladium and gold as a insoluble compounds on the support by immersing and tumbling the impregnated support in a reactive solution for at least 1/2 hour to precipitate such compounds, and subsequently reducing the compounds to free metallic form.
U.S. Pat. No. 5,347,046, issued Sep. 13, 1994 to White et al., discloses catalysts for the production of vinyl acetate by reaction of ethylene, oxygen, and acetic acid, comprising a palladium group metal and/or a compound thereof, gold and/or a compound thereof, and copper, nickel, cobalt, iron, manganese, lead or silver, or a compound thereof, preferably deposited on a support material.
U.S. Pat. No. 5,567,839, issued Oct. 22, 1996, to Gulliver et al., discloses a method of producing vinyl acetate catalysts including the step of using a barium "salt", such as barium hydroxide, to precipitate water-insoluble palladium and gold compounds onto a support prior to reduction with a reducing agent. When barium hydroxide is used as precipitant, residual barium remains in the finished catalyst. | {
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1. Field of the Invention
The present invention relates to a display device having a self-light emitting element.
2. Description of the Related Art
In recent years, a display device using a light emitting element (self-light emitting element) has been actively researched and developed. Such a display device is widely used as a display of a portable phone or a monitor of a computer by taking advantages of high image quality, thin design, lightweight and the like. In particular, such a display device provides high response speed suitable for displaying moving images, low voltage, low power consumption drive and the like, therefore, its wide applications such as a new generation portable phone and a portable information terminal (PDA) are expected.
A light emitting element is also referred to as an organic light emitting diode (OLED) and has a structure having an anode, a cathode, and a layer containing an organic compound between the anode and the cathode. The amount of current supplied to the light emitting element and a luminescence of the light emitting element are in a certain relationship. The light emitting element emits light at a luminescence according to the amount of current supplied to the layer containing the organic compound.
The major methods for displaying a multi-gray scale image by a light emitting device using a light emitting element are a voltage input method and a current input method. According to the voltage input method, a video signal inputted to a pixel is inputted to a driving element, thereby a luminescence of the light emitting element is controlled. According to the current input method, a set signal current is supplied to a light emitting element, thereby a luminescence of the light emitting element is controlled. Both methods can employ an analog driving method (analog gray scale method) and a digital driving method (digital gray scale method).
In order to prevent variations in characteristics of element driving thin film transistors which correspond to driving elements of light emitting elements in the voltage input method, a semiconductor device provided with a compensating thin film transistor between a driving power source and the element driving thin film transistor has been suggested.
[Patent Document 1]
Japanese Patent Laid-Open No. 2002-175029
In the aforementioned patent document, variations in the threshold voltage of transistors (referred to as driving transistors) which control driving current according to gray scales is not taken into consideration. However, the inventors figured out that in the case of performing a low gray scale display in which a minute current is supplied to the light emitting element, variations in threshold voltages (Vth) become notable since a gate-source voltage (Vgs) of the driving transistor, that is a potential difference between the gate electrode and the source electrode is small. | {
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This invention relates generally to postage meters and more particularly is concerned with postage meters of the type that includes an ink jet print head above a registration plate.
In one conventional variety of postage meter, an ink jet print head is employed to print a postage indicium on an envelope. The ink jet print head is moved on a path above the top surface of the envelope and emits ink in a downward direction toward the envelope. To ensure proper printing, the vertical spacing between the envelope surface and the print head is critical. A horizontal registration plate positioned below the print head defines the ideal spacing between the print head and the envelope surface. A spring-loaded platform below the envelope presses the envelope upwardly against the registration plate. A window is formed in the registration plate and the ink from the print head is propelled through the window at the top surface of the envelope to form the postage indicium.
A potential problem with postage meters of this type is that envelopes having a “puffy” cross-section may, when pressed by the platform, partially enter through the window in the registration plate. When this occurs, the top surface of the envelope may enter through the window to such an extent that the envelope comes into contact with the print head. When this occurs, damage to the print head may result, as well as smearing of the postage indicium.
One way of reducing the possibility of entrance of a puffy envelope into the window is to limit the size of the window so that the edge of the window is spaced a sufficient distance in a horizontal direction from the edge of the envelope. However, limiting the size of the window may prevent printing of as large a postage indicium as would be desirable. | {
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1. Field of the Invention
The present invention relates to an electric potential sensor, and more particularly, to a feedback type electric potential sensor which measures the electric potential of an object by causing the electric potential of the sensor to be equal to the electric potential of the object.
2. Description of the Related Art
Recently, many devices (for example a PPC copying machine or a laser printer, an electrostatic dust remover) utilize static electricity. In such devices, a sensor for measuring electric potential at a charged part is essential in order that the electric potential at the charged part can be maintained at a desired value.
FIG. 4 is a schematic diagram showing an example of such an electric potential sensor. This sensor detects an electric potential Vt of an object OBJ in non-contact manner. The sensor includes a pickup device Pu which calculates the difference between the electric potential Vt of the object OBJ and an electric potential Vdet at a detection node DET and controls the base current IB of transistor Tr so that the difference between the electric potential at the detection node DET and the electric potential Vt of the object OBJ becomes 0. The electric potential Vdet at the detection node DET is divided by resistances Ra and Rb (which are situated between the detection node DET and ground GND) and is output at output node OUT. This output is indicative of the electric potential of the measuring object OBJ is to be measured.
There are several drawbacks to the prior art system. Because one side of the power source HV is grounded, only either a positive electric potential or, alternatively, a negative potential can be measured. Further, due to the influence of the leakage current of the transistor Tr, and the like, it is difficult to accurately measure a 0 V electric potential which may be a threshold value in a measuring range of the sensor. For example, in a sensor used to measure a positive electric potential, a 0 V electric potential and negative electric potentials cannot be distinguished, etc.
To overcome these problems, there has been proposed an electric potential sensor shown in FIG. 5 which can measure both positive and negative electric potentials. In this sensor, two power sources HV1 and HV2, and two transistors Tr1 and Tr2, are provided. The mutual connection node of the power sources HV1 and HV2 is grounded, and resistances Rc and Rd are provided between grounded GRD and the detection node DET. As a result, both positive and negative electric potentials can be measured, and 0 electric potential can be accurately measured. However, the structure of this sensor is complex and its cost is high. | {
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1. Field of the Invention
The present invention relates generally to systems for manufacturing relatively wide sheets of continuous composite material. More particularly, the present invention relates to a system for controlling the lateral position of a sheet of composite material as it moves longitudinally through a curing oven.
2. Description of Related Art
Large sheets of composite material are used for a wide variety of purposes. These sheets of composite material are typically made from resin impregnated fibers, such as fiberglass. The sheets are available as flat panels or contoured panels which are typically used in constructing patio covers, carports, storage sheds, fences, awnings, dividers and screens, home and industrial greenhouses, wall and truck liners, cabanas, sunrooms, garage doors, and a variety of other applications. Flat and corrugated panels are also widely used as siding for recreational vehicles and vans.
Composite material panels or sheets are typically manufactured as relatively wide continuous sheets which are cut into the desired size panels after fabrication and curing. An exemplary process for such manufacture is described in U.S. Pat. No. 3,077,000 which was issued on Feb. 12, 1963. The basic process disclosed in this patent and utilized in the manufacture of composite material sheeting involves forming a layer of uncured composite material which is supported by a lower support film layer. A top or upper film layer is added to form an uncured sheet of material having the uncured composite material layer sandwiched between the lower support film and upper film. Curing of the composite material is accomplished by transporting the continuous sheet of material through a series of curing ovens. The sheet exits the curing ovens as a completely cured composite panel. At that time, the lower support and upper film layers are removed. The composite sheeting is then cut or otherwise fabricated into the desired panel sizes.
As the relatively wide sheet of composite material pass longitudinally through the curing ovens, it is important to control the lateral position of the sheet so that it does not contact the curing oven walls or other surfaces. Without adequate control of the lateral position, the sheet of composite material tends to wander laterally back and forth causing damage to the sheet edges. Further, it is important when preparing contoured sheets of material that the lateral position of the composite sheet be accurately maintained to prevent misalignment between the composite sheet and the dies used to form the contours. | {
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This invention relates to the preparation of ceramic composites having a ceramic fibrous cloth or matt substrate or filament wound structure which has been impregnated and coated with a ceramic by a chemical vapor deposition process. The composites are particularly useful as components of heating furnaces or for other high temperature or wear applications. More particularly, the invention relates to applying nucleation sites in and on the fibrous substrate to achieve a more thorough infiltration of the substrate by the subsequent CVD coating. Silicon carbide and silicon nitride composites so produced are particularly useful as components of semiconductor diffusion furnaces.
In the overall manufacturing process for the production of semiconductors devices, such as diodes, transistors, and integrated circuits, a critical part of the process involves multiple steps of elevated temperature processing. The process involves oxidation and doping of thin silicon wafers interspersed with steps of etching of cavities or patterns on the wafer surfaces. The semiconductor devices may be made both separately and in an integrated circuit array. The oxidation steps and various doping and coating operations to which the silicon slices are subjected involve multiple heating and cooling cycles at temperatures in the range of from 400 to 1350.degree. C. These critical thermal processing steps generally take place in special electrically heated muffle furnaces. The silicon slices are generally placed in quartz, silicon carbide, silicon impregnated silicon carbide, or polysilicon boats, jigs, or fixtures which are then placed within a process tube of the muffle furnace so that the silicon slices can be processed through a predetermined time/temperature/atmosphere cycle. The atmosphere is carefully controlled and gases are usually fed into the necked-down end of the diffusion furnace process tube. In the process the silicon slices in the boats are typically supported on a paddle.
The components and process tubes used in the process must have excellent thermal shock resistance in order to permit the rapid heating to, and rapid cooling from, temperatures in the order of about 400.degree. C. to about 1350.degree. C. back to room temperature. The components and other furnace parts must also be of high mechanical strength at both elevated and room temperatures, have the ability to retain their shapes through a large number of heating and cooling cycles, not outgas, i.e. introduce any undesirable impurities into the process atmosphere during elevated temperature operations, and not introduce any dust-like contamination. Cleanliness and control of impurities are extremely important to producing semiconductor devices having the desired electrical characteristics.
The demanding conditions severely limit the materials which can successfully be used to fabricate diffusion furnace parts or components. Generally, a furnace consists of an external furnace liner which fits in the annular space between a heating element and a process tube; the process tube which fits into the liner and has a necked-down end for the introduction of the desired atmosphere; and a paddle, either as a wheeled carrier or as a cantilevered support, upon which are placed what are known as "wafer supports" or "boats". Occasionally an "internal" liner is used inside the process tube, particularly for processes involving progressive build-up of deposits. This internal liner can be tailored to have desirable properties and generally is designed to be replaced without having to replace the process tube. An alternative furnace configuration entails having the outermost tube as the process tube and containing an inner tube which also is a liner. Thus there can be external or outer liners and inner liners. Whenever the term "liner" is used herein, it is meant to include both external and internal liners unless one of the two is indicated. The process tube, paddle, and boat, have often been made of fused silica quartz while the liner has sometimes been composed of mullite or alumina. However, the silica components have been known to lose their mechanical strength and progressively devitrify with time at the processing temperatures involved. In addition, quartz components are very susceptible to extreme distortion due to the cyclic heating and cooling and also do not long withstand the frequent hydrofluoric acid cleaning which is normally required to maintain the necessary ultra-pure furnace environment. In a more recent modification of the process, the furnace liner, i.e. the tube which surrounds and supports the process tube, has been formed from silicon carbide, instead of mullite and alumina, and used with a quartz process tube or inner tube. Silicon carbide possesses high thermal conductivity and high strength as compared to the other materials and furthermore provides a barrier to sodium and other metallic ions coming from the heating element and related components. However, the initial silicon carbide bodies used were porous and permeable and therefore could not provide the controlled atmosphere and high purity environment required for many semiconductor manufacturing processes. U.S. Pat. No. 3,951,587 discloses furnace components composed of silicon carbide that are at least 99% pure and which are then impregnated with silicon which is at least 99.9% pure. Due to the high strength, imperviousness, and purity of this composition, it could be used as a process tube without need of a separate liner which saved space and improved overall purity and dependability. However, there are some operations where the free silicon is a problem.
One attempted solution to these problems in disclosed in U.S. Pat. No. 4,766,013 which discloses the use of a fibrous substrate which is carbonized to form a layer of pyrolytic carbon on the fibers and then the carbon-coated fibers are impregnated with, among others, silicon carbide by a chemical vapor deposition (CVD) procedure. The fibrous substrate may be silicon carbide fibers. The pyrolytic carbon coating is required to enable the fibers to be free to move relative to the CVD coating.
It is a principal object of the present invention to provide ceramic composites suitable for use as diffusion furnace components viz. liners and/or process tube, paddle, and boat, which have reduced porosity, superior oxidation resistance, thermal shock resistance, increased strength, the ability to retain their shape and composition through a large number of heating and cooling cycles, and improved impermeability to gases.
It is a further object to produce ceramic materials having a density of greater than about 70%, more preferably greater than 80%, and most preferably greater than about 85% of the theoretical density by a chemical vapor deposition of a ceramic onto fibrous ceramic substrates. | {
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The present disclosure generally relates to the field of electronics, and more particularly to a semiconductor device.
Semiconductor devices may include logic circuit devices, flash memory devices, dynamic random access memory (DRAM) devices, magnetic random access memory (MRAM) devices, and phase change RAM (PRAM) devices. Semiconductor devices may be manufactured through unit processes including, for example, a deposition process, a photolithography process, an ion implantation process and an etching process. As design rules of semiconductor devices decrease, production yields and/or productivity of the semiconductor devices may decrease. | {
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A standard column or prop used in a mine to hold up the ceiling or roof comprises a pair of aluminum or steel tubular tubes that telescope in each other. The outer end of one of the tube is braced against the ceiling surface and the outer end of the other tube is braced against the floor surface while the inner ends fit within each other. As described in U.S. Pat. Nos. 3,737,134 and 4,185,940 respectively of Foon and Spies the upper end of the outer tube is frustoconically upwardly flared and annular wedges engage between this flared region and the inner tube. These wedges allow the tubes to be moved axially apart but resist movement together as the wedges bite into the inner tube. The wedges permit some downward movement of the inner tube in the outer tube, giving the column its vertical resiliency. The upper end of the inner tube is formed as a nut into which is threaded a massive bolt whose upper end bears via a rigid dished plate on the ceiling, this plate having no significant resiliency. The setting force, that is the vertical load the column is set to bear, is established by screwing this bolt out of the column against the ceiling.
The wedges allow the prop to be compressed vertically to a limited extent if the ceiling or floor shifts. Thus for a slight shift the prop will not collapse but will remain in place. Once the column has shortened somewhat, it becomes solid and resists any further shortening. Thus such a prop acts like a pressure-relief valve.
With such systems it is fairly difficult to set the starting post length, which determines the setting force, accurately and easily. Normally the parts that establish this post length (and the setting force) are independent of the elements that provide for resiliently resisted telescoping together. Thus the known props are excessively complex and expensive, which is particularly disadvantageous since they are normally set and left, that is they cannot easily be reused. | {
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In the 3GPP (3rd Generation Partnership Projects), services are prescribed that are referred to as MBMS (Multimedia Broadcast Multicast Services) (see Patent Documents 1 and 2).
MBMS is a service in which multimedia data such as moving pictures or music (hereinbelow referred to as MBMS data) are simultaneously transmitted by broadcast or multicast to a plurality of mobile stations.
In addition, a system referred to as an MBSFN (Multimedia Broadcast Single Frequency Network) is prescribed in 3GPP as a mode of offering MBMS.
An MBSFN is a mode in which each of a plurality of wireless base stations sets an identical wireless parameter set (such as frequency) in channels used in transmitting MBMS data in cells that are formed by these wireless base stations and transmits identical MBMS data to mobile stations.
Thus, as seen from mobile stations, a plurality of cells that are formed by each of a plurality of wireless base stations can be considered as one large communication area. This communication area is referred to as an MBSFN cluster.
In a W-CDMA (Wideband Code Division Multiple Access) wireless communication system, a wireless base station (NodeB) and Radio Network Controller (RNC) are typically split between different apparatuses.
As a result, when an MBMS is offered using an MBSFN in a W-CDMA wireless communication system, the radio network controller designates to wireless base stations, that are under its jurisdiction, wireless parameters that are to be used by the wireless base stations.
Coordination of wireless parameters can thus be established among wireless base stations and an MBSFN cluster can be formed that straddles a plurality of wireless base stations. | {
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1. Field of the Invention
The present invention relates to thermal transfer recording method and more particularly to an improved thermal transfer recording method of the type including ink ribbon which can be repeatedly used.
2. Description of the Prior Art
In the hitherto known facsimile apparatus, as means for receiving image informations of an original and recording them, electrostatic recording method and thermal transfer recording method are mainly employed for the signal receiving and recording mechanism. The electrostatic recording method has an advantageous feature that recording can be effected at a high speed with high image resolvability, but it has drawbacks that the apparatus using this method is complicated and expensive because developing and fixing of images are required. In addition, recording paper used in this apparatus is expensive, resulting in comparatively increased running cost. On the other hands, the thermal transfer recording method has advantageous features that developing and fixing of images are not required because the image is built by primary coloring under the effect of heating and an apparatus using this method can be constructed in the comparatively simple manner, but it has drawbacks that recording papers are of specially produced type which have less durability and the images recorded thereon can be falsified relatively easily.
In view of the problem inherent to the recording methods as described above, it has been proposed the thermal transfer recording apparatus for a facsimile equipment in which inexpensive ordinary paper is employed as recording medium. The thermal transfer recording apparatus of this type is operated such that recording paper made of ordinary paper and ink ribbon serving as master recording material and comprising a base film made of paper, plastic or the like material with a layer of thermally fusible solid ink containing coloring agent coated thereon are superimposed one above another so that the ink layer comes in contact with the recording paper and they are transported in a certain direction while the base film is depressed by means of a platen roller so as to allow it to come in contact with heating resistor elements of a thermal head. When pulse electric current is selectively caused to flow through the heating resistor elements in response to signals representing an image to be recorded, heat is generated at the heating resistor elements. The generated heat is transmitted to the solid ink layer through the base film of ink ribbon. Thus, the solid ink layer becomes in a semi-fused state a viscous. The semi-fused ink is transferred to recording paper under the influence of pressure given by the platen roller whereby a permanent image is built on the paper.
Since this type of recording apparatus uses ordinary paper as recording medium and does not require processes of developing and fixing, running cost can be reduced considerably and can be manufactured in a simple construction, in smaller dimensions and at an inexpensive cost. Further, since coloring agent having excellent weather proofness is used for the ink which is transferred only onto a required area on the paper, the recording paper and the recorded images are durable for a longer time and falsification of the recorded image is difficult to make compared with the foregoing heat sensitive recording apparatus.
However, it has been pointed out that the existent thermal transfer recording apparatuses fail to satisfactorily meet a variety of requirements for receiving and recording image signals, when used in a facsimile apparatus.
Generally, the conventional facsimile machine is adapted to handle originals having a variety of lengths and therefore the receiving apparatus is required to effect recording in which the recorded paper has the same length as that of the original. For the reason, it is preferable to use a roll of recording paper wound about a core as recording medium and automatically cut it off by the same length as that of an original by actuating an automatic cutter after completion of recording operation of received signal informations. However, in the case where the conventional thermal transfer recording system is applied to a receiving apparatus of a facsimile, sheet papers cut to a predetermined length, for instance, the length of A4 (29.7 cm) or B4 (36.4 cm) are usually used as recording medium, the length of an original of which image signal can be perfectly transmitted to the receiving apparatus is limited within the extent of the length of a single sheet paper or shorter than the length of the same. Further, the conventional facsimile receiving apparatus is constructed such that the length of ink ribbon is determined equal to the length of recording paper in the one-to-one relation. Therefore, when image informations of an original whose length is shorter than the length of a recording sheet paper are received by the facsimile receiving apparatus, both the ink ribbon and the recording paper are caused to have a blank area which is not concerned with recording. However, this is not preferable and acceptable from the viewpoint of cost and recording process. Another drawback of the conventional thermal transfer recording system is that recorded image is clearly kept on the ink ribbon in the form of a negative image after completion of recording operation. Therefore, there will arise a fear of leaking confidential informations from the used ink ribbon. | {
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Contemporary and future aerospace vehicle requirements continue to provide challenges to the structural designer for reducig structural weight. In the interst of fuel economy, a premium is placed on structural weight in the design aircraft. Similarly, the anticipated needs for very large area space structures will tax the load carrying capability of any conceivable booster system. Relative recent advances in filamentary composite materials have provided the structural design improvements of a factor of two to four in strength-to-density ratios and a factor of three to eight in modulus-to-density ratios when compared with the normally used metal structures. To fully exploit this potential, structural designs must be developed wherein the unidirectional nature of the advanced composite materials is considered from the outset.
Accordingly, it is an object of the present invention to provide a new and improved lightweight structural panel.
Another object of the present invention is the provision of a novel panel construction.
A further object of the present invention is the provision of a lattice type structural panel wherein the unidirectional characteristics of filamentary compositions are exploited.
An additional object of the present invention is the provisions of composite material panel structure wherein the geometry of the panel lattice network is tailored to provide the appropriate stiffness and loading requirements.
A further object of the present invention is a novel method of making a composite lattice panel structure. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
This invention relates to a V-type engine.
2. Description of the Prior Art
In Japanese Unexamined Patent Publication No. 55(1980)-114845, there is disclosed a V-type engine in which a pair of V-arranged banks are mutually displaced in the axial direction of the crankshaft so as to provide spaces at a location axially ahead of one bank and at a location axially behind the other bank, and auxiliary mechanisms for the engine to be driven by the crankshaft are separately disposed in the spaces. With this arrangement, the overall size of the engine can be reduced. However, this arrangement is disadvantageous in that an oil-return passage having a sufficient cross-sectional area for oil from the upper surface of the cylinder head cannot be formed in the cylinder block since the end surfaces of the cylinder block are stepped, i.e., the front end and the rear end of one bank are respectively displaced axially from those of the other bank. This leads to poor recovery of oil. This is a significant problem particularly in a V-type overhead-camshaft engine in which a large amount of oil is fed to the cylinder heads. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
This invention relates to pharmaceutical compositions for application to the skin and to a method for the treatment of proliferating skin diseases. The composition may be applied topically. The treatment can be either therapeutic or prophylactic.
2. Description of Related Art
Proliferative skin diseases are widespread throughout the world and afflict millions of humans and their domesticated animals. This invention provides a method for treatment of such diseases. As used hereinafter in this specification and in the claims, the expression “proliferative skin diseases” means benign and malignant proliferative skin diseases which are characterized by accelerated cell division in the epidermis, dermis or appendages thereto, associated with incomplete tissue differentiation. Such diseases include: psoriasis, atopic dermatitis, non-specific dermatitis, primary irritant contact dermatitis, allergic contact dermatitis, basal and squamous cell carcinomas of the skin, lamellar ichthyosis, epidermolytic hyperkeratosis, premalignant sun-induced keratosis, non-malignant keratosis, acne, and seborrhic dermatitis in humans and atopic dermatitis in domesticated animals.
Heretofore, proliferative skin diseases have been generally accepted by mankind as an ongoing evil having degrees of severity variable with inherited skin traits and external factors but always have been recognized as unsightly, painful, morbid diseases. Over the history of mankind innumerable medicines and treatments have been proposed, tried and used with varying degrees of success.
Treatments which are prescribed and used for the treatment of proliferative skin diseases include the following: (1) topical applications, e.g. coal tar derivatives, 5-fluorouracil, vitamin A acid, glucocorticoids in high dosage, bath oils and non-specific emollient creams and ointments; (2) systemic administration, e.g. glucocorticoids and classic anti-cancer agents, for example, methothrexate, hydroxyurea, azaribine, cyclophosphamide; and (3) physical modalities, e.g. ultra violet light, x-radiation, and, in severe cases, surgery.
While these treatments provide, in certain cases some remission of the original symptoms, each treatment suffers some defect, for example, temporary and incomplete mitigation of symptoms, rapid re-occurrence of the disease when mitigation is terminated, serious and sometimes irreversible damage (atrophy) resulting from the topical application for extended times of glucocorticoids, acute bone marrow suppression, cirrhosis of the liver resulting from the protracted use of methothrexate which may lead to death of the patient, and the causation of cancer by the application of anti-cancer drugs, x-radiation, or ultra violet rays.
Recently, a new compound has been approved by the Food and Drug Administration for the treatment of psoriasis and acne. Tazarotene. Tazarotene is available as Tazorac® 0.1% and Tazorac® 0.05% topical gel from Allergan, Inc. of Irvine, Calif. | {
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Gray scale images of various documents are often stored on microfilm for subsequent retrieval in order to conserve storage space by advantageously eliminating the need to store bulky originals. Retrieving (accessing) a microfilmed image of a document, on a manual basis, typically requires locating a desired roll of microfilm that houses the desired image, loading the roll into a manual reader and then advancing the microfilm to a desired frame at which the image is located. Thereafter, the image is optically enlarged and displayed on the reader.
Now, to minimize image retrieval time, particularly for archives that store a substantial number of documents, and also to permit the retrieved image to be electronically enhanced and processed, image management systems have been developed in the art. These systems are typified, for example, by the Kodak Image Management System (KIMS) system currently manufactured by the present assignee (KIMS is a trademark of the Eastman Kodak Company). Essentially, the KIMS system first locates the desired microfilm roll and frame through a computerized database inquiry. Then, an automated microfilm reader, i.e. a so-called film library also known as an autoloader, operating under computer control, fetches and then loads the desired roll into the reader. Once this has occurred, the film library automatically advances the roll to the desired frame. Thereafter, the film library electronically scans and digitizes a gray scale microfilm image present at the desired frame, and finally applies the resulting digitized bi-tonal image onto a local area network for storage, display and/or printing.
Within the KIMS system, the microfilm image of a document is scanned one line at a time by a microfilm scanner and specifically by a 2048-by-1 cell charge coupled device (CCD) array located therein. The array is positioned directly over (or in front of) the microfilmed image and is oriented substantially perpendicular to a direction through which the microfilm moves through the reader. A lamp situated below (or behind) the microfilm projects light through the image. As a result, each cell of the CCD array provides an analog signal which is proportional to the intensity of the light that passes through that portion of the scanned area of the microfilm which lies directly below (or behind) that element. The scanned area is generally 25 to 50% larger than the actual image of the document. In this manner, the full image is scanned even if a the document used to form the image was photographed somewhat off center or tilted and/or if the CCD becomes slightly horizontally mis-aligned with respect to the microfilm. Overscanning is necessary particularly where rotary microfilmers have been used to photograph images onto microfilm. These filmers cause a wide variation in the location and orientation of the photographed document within a a standard image area. Now, as each pixel (pel) is scanned, the analog signal corresponding to the intensity of that pixel is converted into a six bit digital signal which itself is subsequently thresholded to provide a single bit binary output signal for that pixel. All the single bit binary values are stored in a frame store memory. Once scanning has been completed, then the contents of the frame store memory which stores the scanned image of the document are routed to a video compressor. Thereafter, the compresed bi-tonal image is sent to the local area network for storage, display and/or printing by downstream electronic processing equipment.
Typically, a scanned bi-tonal microfilmed image which appears on the network may be deficient in quality. This deficiency can result primarily from image noise and/or edge discrepancies.
Image noise takes the form of undesirable pixel transitions (i.e. from white to black, or black to white) occurring in the image. Therefore, to improve image quality and increase compressibility, these undesirable pixel transitions must be removed from the image. Image compressibility increases as the number of pixel transitions decreases. However, fine detail, such as small characters, typically spans a relatively small number of pixels. Therefore, as increasingly larger groups of isolated pixels are removed as noise, compressibility rises but fine detail is removed from the image and hence image quality degrades. Consequently, a tradeoff exists between image quality and compressibility in determining the size of isolated pixel groups that are to be removed, as noise, during a process of image enhancement.
To achieve a good compromise between image quality and compressibility, image noise is typically viewed as being a single isolated "on" (black) pixel occurring anywhere in the image. Any larger sized pixel groups are viewed as desirable detail which are to be left in the image. Image noise typically originates from any one of three sources: so-called paper noise existing in the document itself that has been microfilmed, so-called film noise caused by the grain size in the microfilm medium and electronic noise generated by the electronic scanning system.
Now, to properly threshold an image in order to remove image noise, a threshold level must intersect video pulses that form textual characters, in the scanned image, at a point that occurs above a pre-defined noise amplitude but below the peak amplitudes of these pulses. One technique for sensing the proper noise amplitude is to observe the occurrence of single isolated pixels that occur throughout the scanned image. Specifically, in the KIMS system, a microfilm image is scanned at a typical density of 200 pixels to the inch (approximately 79 pixel/cm). Noise generally takes the form of an isolated pixel of one color, i.e. black, surrounded by pixels of another color, i.e. white. A pixel of this size is simply not readily visible to an average reader. As such, a single isolated pixel does not form any part of a textual character but is instead noise. Single pixel noise can be one-dimensionally isolated wherein a single pixel is "on" while its neighbors to its left and right are both "off", or two-dimensionally isolated wherein the single pixel is "on" while its neighbors to the left, right, above and below and possibly also those which are diagonally oriented to the single pixel are all "off".
Ideally, then, one could set the threshold level to an appropriate level to filter out single pixel noise from the six bit digitized video. Unfortunately, in practice, single pixel noise can occur at various intensity levels throughout the full range of video amplitude in the scanned image thereby significantly complicating the process of thresholding. Specifically, first, single pixel noise can occur on the peaks of the video signal which correspond to detected pixels that form a textual character that appears on a background having the highest contrast, e.g. those pixels that form a black character on a white background. If the threshold were to be set to this level, then disadvantageously any character that is situated on a background having a reduced contrast, e.g. a gray character on a white background, would be entirely removed from the image. Specifically, the pixels which form these characters would not possess as high a peak amplitude value as those which form characters situated on the highest contrasting background and hence would be removed by the thresholding operation. Consequently, thresholding at this level would produce erroneous pixel patterns and hence incorrect text. Second, single pixel noise can also occur just above the level of the background video. The background level in the video signal corresponds to the proper background level of the scanned image. Single pixel noise which occurs here accurately indicates noise amplitude in the scanned image. Hence, setting a threshold value slightly above the background level will result in accurate thresholding of image noise. Third, single pixel noise can occur below the background level of the video signal. If this were to be used as a threshold value, then an excessive amount of noise would remain in the image and hence adversely affect image compressibility.
Now, since the background level may vary significantly across any line in the scanned image, the threshold level must track the background level and be dynamically maintained at a value slightly greater than the background level.
Edge discrepancies, the second primary cause of image quality degradation, often occur whenever an image is drastically reduced in size, such as through microfilming, which, by its very nature, eliminates a great deal of information from an original image. In particular, microfilm possesses a finite resolution, as does all photographic media, which tends to limit the size of the detail that can be photographed on the microfilm. If fine detail exists in a document and is reduced to a size which is smaller than this resolution, then this detail will be blurred in the microfilmed image and hence will appear blurred in any image that results from scanning the microfilmed image. Consequently, image edges in a scanned microfilmed image may often appear ragged and/or blurred instead of straight. Therefore, to improve image quality, all image edges should be sharpened during image enhancement.
Therefore, an overall need exists in the art for a system that enhances the quality of a multi-bit scanned image, particularly one resulting from a scanned microfilmed image and then accurately thresholds each pixel in the bi-tonal image into a single bit binary value. This system would enhance the image by both removing image noise therefrom and sharpening the edges of the image. Such a system would advantageously find particular use in improving the quality of images generated by an image management system.
Moreover, in practice, various problems have arisen whenever scanned pixel values obtained through a CCD array are digitized and then enhanced. Specifically, a CCD array provides two channels of output. Generally, to increase response time of the array, all the odd CCD cells in the array are connected to one output channel, while all the even cells are connected to the other output channel. In response to an appropriate control signal, the array simultaneously scans an entire scan line in the image with each cell providing an analog value representing reflectance (light intensity) of a corresponding pixel in that line. Now, once the line has been scanned, various relatively high speed clock signals are applied to the array to shift the analog value produced by each cell to the appropriate output channel of the array. Consequently, the output produced by the array alternates between both channels as adjacent pixel values that form the scanned image are shifted out of the array. To provide discrete digital pixel values, both output channels of the array are alternately sampled and digitized. Unfortunately, offsets frequently develop and often increase over time between the response of the two channels in the array. Therefore, to minimize errors due to such offsets, each pair of adjacent odd and even digital pixel values are averaged (this process typically referred to as "odd/even averaging") and the resulting average value for each pixel is then enhanced. However, certain image enhancement techniques known in the art require use of the original, not averaged, pixel values in order to provide accurate results. Therefore, for these techniques, incoming non-averaged original (raw) pixel values were frequently stored for subsequent use along with their average values. Since scan lines require 2048 pixels each of which is typically converted into 6 bits, large memories or delay lines were required to store the original pixel values. This additional storage added to the expense of the enhancement system and, with the necessary addressing circuitry, added additional complexity to the system.
Therefore, a specific need also exists in the art for a simple and inexpensive circuit that is able to deaverage a stream of averaged pixel values in order to reconstruct the original pixel values appearing in that stream. Furthermore, such a circuit should be particularly suited for use in conjunction with a system for enhancing scanned microfilmed images that occur within an image management system. The present invention addresses this specific need. Now, by satisfying this specific need, the inventive circuit advantageously facilitates meeting the overall need through use of the image enhancement system disclosed herein. | {
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FIGS. 1 and 2 show a conventional motor structure disclosed by U.S. Pat. No. 6,654,213, which includes a housing 70, a rotor 80, and a stator 90. Referring to FIG. 1, the housing 70 includes a hollow shaft tube 71 receiving a bearing 72. The shaft tube 71 has an opening 711 at an upper end thereof for the bearing 72 to be inserted into the shaft tube 71, while the shaft tube 71 peripherally has a support face 712 facing upwards. The rotor 80 includes a shaft 81 rotatably extending through the bearing 72. The stator 90 is mounted around the shaft tube 71 and includes an upper bobbin 91, a lower bobbin 92, a plurality of silicon steel plates 93 sandwiched between the upper and lower bobbins 91 and 92, and a winding 94 wound around the silicon steel plates 93. The upper bobbin 91 includes an abutting portion 911 in the form of an annular ring extending inwards radially to block an outer rim of the opening 711, preventing disengagement of the bearing 72 from the shaft tube 71 via the opening 711. The bearing 72 and shaft tube 71 are in loose coupling with each other and have a small gap therebetween to allow easy assembly and to prevent the shaft tube 71 from being squeezed and thus deformed by the bearing 72. Furthermore, the support face 712 of the shaft tube 71 faces and abuts against the silicon steel plates 93 so as to support and position the stator 90 relatively to the housing 70.
However, referring to FIG. 2 showing a cross sectional view of the conventional motor structure while the housing 70, rotor 80, and stator 90 are assembled, it is apparent that, in an axial direction along the shaft tube 71, a first distance between the abutting portion 911 and a lower end of the plurality of silicon steel plates 93 must be equal to a second distance between the opening 711 and support face 712, or the stator 90 cannot surely rest on the support face 712 if the first distance is shorter than the second distance, or the abutting portion 911 is unable to firmly block the outer rim of the opening 711 if the first distance is longer than the second distance. Therefore, the accuracy in sizes of the housing 70 and stator 90 is extremely required. Similarly, since the abutting portion 911 merely extends inwards in radial directions of the shaft tube 71 to block the outer rim of the opening 711, a top end of the bearing 72 must just locate at the opening 711 for the abutting portion 911 to abut against. It should be noted that all of the above requirements have to be extremely fulfilled, or damages to the stator 90, especially to the abutting portion 911, or axial vibration of the bearing 72 will be caused. Accordingly, the manufacture cost of this conventional motor structure is high, in particular to those applied to miniature motors, for exactly making the housing 70, rotor 80 and stator 90 by precision machines and processes. As a result, it is necessary to improve the conventional motor structure for a lower cost of manufacture and a desirable positioning performance. | {
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This invention relates to amusement device or game and more particularly to an electrically operated device which visually or audibly indicates the completion of an act.
This invention concerns a game of pursuit, where the position of a probe on a section of a board is tracked by manipulating a complementary probe on a second section of the board. Each probe is controlled by a different player, and the movements of each probe are hidden from the view of the opposing player. Means are provided to indicate when the probes have been placed in corresponding identical positions on either section of the board indicating that the pursuer has captured its prey.
Generally speaking, games of pursuit are well known in the art. It is known, for instance, to provide a board game on which shorting pins in the form of small boats are inserted into connectors on a board face having complementary designs on either side of a view-blocking board in an effort to obtain coincidence of position. The connectors on the board are interconnected through a resistance network which also forms part of an oscillator circuit such that as the boats on either side approach the same location a continuously emitted audio signal changes pitch or other characteristic. This game is quite complex and requires a substantial amount of skill in its execution.
It is also known in the art to have a position matching or number matching game where a number selected on one board must be matched by a number selected on another through closure of a switching network. Thus, a number selected on one board must be guessed by the player operating a second board interconnected to the first. Indicators are provided to show correct or erroneous guess. In a variation of the above, pins may be inserted in one side of a double-faced board and a second player may try to match his position through insertion of pins on the other side. When two pins are inserted in the same position from both sides of the double-faced board, the pins act to complete the electrical circuit and indicate a match. The nature of those games is such that pure chance is involved in completing a match, or in the alternative, it is suggested that clues be given so that through intellectual deduction a match may be achieved.
It has now been found that a game of pursuit may be made quite exciting to play without need of high skill, yet without appearing to be a game of pure chance. Thus, it has been found that if the pursuer and pursued in such a game are given certain instructions, objectives or restrictions in their possible choice of movements, the element of pure chance is modified and the interest of the players in the game greatly enhanced. This is especially so if the instructions given to at least one of the players are not known to the other. | {
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Tilting multi-wheeled vehicles, in particular, tilting three wheeled vehicles with two front wheels are operated like motorcycles where such vehicles lean into a turn. Unlike motorcycles, an added extra wheel in front provides additional traction for improved stopping and control of the vehicle on slippery surfaces. This type of vehicle is usually lighter, and can be made narrower than a non-titling three or four wheeled vehicle.
In the prior art, titling three wheelers have generally been of the straddle type, or having a recumbent seat, where the operator rides the vehicle like a motorcycle and controls the lean by shifting his/her body weight and by practicing counter-steer techniques.
Some patents advocate the utilization of tilt lock or tilt limiting mechanisms and footboards on a non-tilting portion (simulating the ground) where the operator can use these boards to control the lean of the vehicle for added safety and stability. Examples of this type are described in U.S. Pat. No. 4,088,199 to Trautwein and U.S. Pat. No. 7,530,419 to Brudeli.
It has also been known to implement tilt control mechanisms, usually hydraulic, pneumatic, or electro-mechanical actuators, connected between a tilting and non-tilting portion of a tilting vehicle. This type of arrangement simplifies the operation of the vehicle where the rider doesn't need to learn how to operate a free leaning vehicle (motorcycle), and can practice simple steer. Such mechanisms are manually activated by the operator or use some type of pendulum device or an electronic control unit that uses the input from different sensors (such as speed, steering angle, lateral forces, etc.) to control the tilt mechanism without user input. While such arrangements provide acceptable tilt control mechanisms, they do not replicate the exact feeling generated by a free leaning motorcycle or tilting three wheeled vehicle. An example of this type of tilt control is described in U.S. Published Patent Application No. 2009/0312908 to Van Den Brink.
Some have described tilting vehicles having an enclosed or partially enclosed cabin mounted on a titling portion of the frame, having enough space for one or two inline (back to back) seats, and just enough width to accommodate one rider. While this type of enclosure provides better protection to the rider than an open tilting vehicle, it usually is relatively narrow since a wide body would touch the ground even at moderate lean angles. This makes it necessary to design the body with a narrow or rounded bottom thus creating a displeasing aesthetic appearance. Further, a narrow titling vehicle is not as safe as a vehicle that can support a wider frame and enclosure (creating a greater buffer zone between the rider and the frame), at least when it comes to side impact in the case of a collision with another vehicle or in the case of a rollover. An extremely narrow enclosure also limits the ornamental design that can be applied to the completely or partially enclosed tilting vehicle, thus reducing the chance of success in the marketplace. | {
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1. Field of the Invention
The present invention relates to techniques for evaluating a subsurface formation using a probe assembly conveyed on a downhole tool positioned in a wellbore penetrating the subsurface formation. More particularly, the present invention relates to techniques for reducing the contamination of formation fluids drawn into and/or evaluated by the downhole tool via the probe assembly.
2. Background of the Related Art
Wellbores are drilled to locate and produce hydrocarbons. A string of downhole pipes and tools with a drill bit at an end thereof, commonly known in the art as a drill string, is advanced into the ground to form a wellbore penetrating (or targeted to penetrate) a subsurface formation of interest. As the drill string is advanced, a drilling mud is pumped down through the drill string and out the drill bit to cool the drill bit and carry away cuttings and to control downhole pressure. The drilling mud exiting the drill bit flows back up to the surface via the annulus formed between the drill string and the wellbore wall, and is filtered in a surface pit for recirculation through the drill string. The drilling mud is also used to form a mudcake to line the wellbore.
It is often desirable to perform various evaluations of the formations penetrated by the wellbore during drilling operations, such as during periods when actual drilling has temporarily stopped. In some cases, the drill string may be provided with one or more drilling tools to test and/or sample the surrounding formation. In other cases, the drill string may be removed from the wellbore (called a “trip”) and a wireline tool may be deployed into the wellbore to test and/or sample the formation. Such drilling tools and wireline tools, as well as other wellbore tools conveyed on coiled tubing, are also referred to herein simply as “downhole tools.” The samples or tests performed by such downhole tools may be used, for example, to locate valuable hydrocarbons and manage the production thereof.
Formation evaluation often requires that fluid from the formation be drawn into a downhole tool for testing and/or sampling. Various devices, such as probes and/or packers, are extended from the downhole tool to isolate a region of the wellbore wall, and thereby establish fluid communication with the formation surrounding the wellbore. Fluid may then be drawn into the downhole tool using the probe and/or packer.
A typical probe employs a body that is extendable from the downhole tool and carries a packer at an outer end thereof for positioning against a sidewall of the wellbore. Such packers are typically configured with one relatively large element that can be deformed easily to contact the uneven wellbore wall (in the case of open hole evaluation), yet retain strength and sufficient integrity to withstand the anticipated differential pressures. These packers may be set in open holes or cased holes. They may be run into the wellbore on various downhole tools.
Another device used to form a seal with the wellbore sidewall is referred to as a dual packer. With a dual packer, two elastomeric rings are radially expanded about a downhole tool to isolate a portion of the wellbore wall therebetween. The rings form a seal with the wellbore wall and permit fluid to be drawn into the downhole tool via the isolated portion of the wellbore.
The mudcake lining the wellbore is often useful in assisting the probe and/or dual packers in making the appropriate seal with the wellbore wall. Once the seal is made, fluid from the formation is drawn into the downhole tool through an inlet therein by lowering the pressure in the downhole tool. Examples of probes and/or packers used in downhole tools are described in U.S. Pat. Nos. 6,301,959; 4,860,581; 4,936,139; 6,585,045; 6,609,568 and 6,719,049 and U.S. Patent Application No. 2004/0000433.
Techniques currently exist for performing various measurements, pretests and/or sample collection of fluids that enter the downhole tool. However, it has been discovered that when the formation fluid passes into the downhole tool, various contaminants, such as wellbore fluids and/or drilling mud may, and often do, enter the tool with the formation fluids. The problem is illustrated in FIG. 1, which depicts a subsurface formation 16 penetrated by a wellbore 14 and containing a virgin fluid 22. A layer of mud cake 15 lines a sidewall 17 of the wellbore 14. Due to invasion of mud filtrate into the formation during drilling, the wellbore is surrounded by a cylindrical layer known as the invaded zone 19 containing contaminated fluid 20 that may or may not be mixed with the desirable virgin fluid 22 that lies in the formation beyond the sidewall of the wellbore and surrounds the contaminated fluid 20. Since the contaminates 20 tend to be located near the wellbore wall 17 in the invaded zone 19, they may affect the quality of measurements and/or samples of the formation fluids. Moreover, contamination may cause costly delays in the wellbore operations by requiring additional time for more testing and/or sampling. Additionally, such problems may yield false results that are erroneous and/or unusable.
FIG. 2A shows the typical flow patterns of formation fluids as they pass from a subsurface formation 16 into a wireline-conveyed downhole tool 1a. The downhole tool 1a is positioned adjacent the formation 16 and a probe 2a is extended from the downhole tool through the mudcake 15 to sealingly engage the sidewall 17 of the wellbore 14. The probe 2a is thereby placed in fluid communication with the formation 16 so that formation fluid may be passed into the downhole tool 1a. Initially, as shown in FIG. 1, the invaded zone 19 surrounds the sidewall 17 and contains contaminates 20. As a pressure differential is created by the downhole tool 1a to draw fluid from the formation 16, the contaminated fluid 20 from the invaded zone 19 is first drawn (not particularly shown in FIG. 1 or 2A) into the probe thereby producing fluid unsuitable for sampling. However, after a certain amount of contaminated fluid 20 passes through the probe 2a, the virgin fluid 22 breaks through the invaded zone 19 and begins entering the downhole tool 1a via the probe 2a. More particularly, as shown in FIG. 2A, a central portion of the contaminated fluid 20 flowing from the invasion zone 19 into the probe gives way to the virgin fluid 22, while the remaining portion of the produced fluid is contaminated fluid 20. The challenge remains in adapting to the flow of the formation fluids so that the virgin fluid is reliably collected in the downhole tool 1 a during sampling.
FIG. 2B shows the typical flow patterns of formation fluids as they pass from a subsurface formation 16 into a drill string-conveyed downhole tool 1b. The downhole tool 1b is conveyed among one or more (or itself may be) measurement-while-drilling (MWD),logging-while-drilling (LWD), or other drilling tools that are know to those skilled in the art. The downhole tool 1b may be disposed between a tool or work string 28 and a drill bit 30, but may also be disposed in other manners know to those or ordinary skill in the art. The downhole tool 1b employs a probe 2b to sealingly engage and draw fluid from the formation 16, in similar fashion to the downhole tool 1a and probe 2a described above.
It is therefore desirable that sufficiently “clean” or “virgin” fluid be extracted or separated from the contaminated fluid for valid testing. In other words, the sampled formation fluid should have little or no contamination. Attempts have been made to eliminate contaminates from entering the downhole tool with the formation fluid. For example, as depicted in U.S. Pat. No. 4,951,749, filters have been positioned in probes to block contaminates from entering the downhole tool with the formation fluid.
Other techniques directed towards eliminating contaminates during sampling are provided by published U.S. Patent Application No. 2004/0000433 to Hill et al. and U.S. Pat. No. 6,301,959 to Hrametz et al., the entire contents of both being hereby incorporated by reference. FIGS. 3 and 4 are schematic illustrations of the probe solution disclosed by the Hrametz patent. Hrametz describes a fluid sampling pad 13 mechanically pressed against the borehole wall. A probe tube 18 extends from the center of the pad and is connected by a flowline 23a to a sample chamber 27a. A guard ring 12 surrounds the probe and has openings connected to its own flowline 23b and sample chamber 27b. This configuration is intended to create zones so that fluid flowing into the probe is substantially free of contaminating borehole fluid.
Despite such advances in fluid sampling, there remains a need to reduce contamination during formation evaluation. In some cases, cross-flow between adjacent flowlines may cause contamination therebetween. It is desirable that techniques be provided to assist in reducing the flow of contamination of formation fluid entering the downhole tool and/or isolate clean formation fluid from contaminates as the clean fluid enters the downhole tool. It is further desirable that such a system be capable of one of more of the following, among others: providing a good seal with the formation; enhancing the flow of clean fluid into the tool; optimizing the flow of fluid into the downhole tool; avoiding contamination of clean fluid as it enters the downhole tool; separating contaminated fluid from clean fluid; optimizing the flow of fluid into the downhole tool to reduce the contamination of clean fluid flowing into the downhole tool; and/or providing flexibility in handling fluids flowing into the downhole tool. | {
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1. Field of the Invention
The present invention relates to an audio device for modifying the voice of the user of the audio device and to a telecommunication terminal capable of modifying the voice transmitted during a telephone call.
2. Description of the Prior Art
Although the transmission of speech remains the essential element of mobile telephony, it nevertheless remains a fact that manufacturers seek to differentiate their products by offering the consumer new attractive and amusing services. Games, services linked to voice recognition, and the multiplicity of ringtones are examples of this.
These new services often involve an additional cost of the telephone linked to the addition of software or hardware elements.
The present invention aims to provide an audio device offering a service of modifying the voice transmitted by the user of the terminal, in particular during a telephone call, this service being of an attractive and amusing kind and simple and economical to implement. | {
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An HMM is suitable for expressing a time-series signal and is widely used in the fields of pattern recognition which processes a time variant signal as in speech recognition and moving image recognition.
An HMM is generally formed from a plurality of states and expressed as an output probability which outputs a signal in each state and a transition probability between states. FIG. 2 shows an example of an HMM formed from three states. Referring to FIG. 2, s is a state index; a(i,j), a transition probability of transition from the ith state to the jth state; and b(i,o), an output probability at which a signal o is output in the state i. In pattern recognition, recognition target events are modeled by a plurality of HMMs. When a time-series signal o(t) (t=1 to T) is observed, a output probability of each event is obtained from the transition and output probabilities of the corresponding HMMs. An event having the highest probability is obtained as the recognition result.
The details of HMMs and pattern recognition methods using HMMs have been introduced by many references, and a detailed description thereof will be omitted. For example, speech recognition using an HMM is introduced in detail in Lawrence Rabiner and Biing-Hwang Juang, “Fundamentals of Speech Recognition”, Englewood Cliffs N.J.: PTR Prentice Hall (Signal Processing Series), 1993.
Speech recognition often uses a continuous mixture distribution HMM representing the output probability distribution as the sum of a plurality of continuous distributions. An example is shown in FIG. 3. The output probability distribution (301) of HMM states is represented by the sum of distribution 1 (302) and distribution 2 (303). An output probability value b(O) at which a signal O is observed is obtained from b(O)=b′(1,O)+b′(2,O) using the output probability b′(1,O) obtained from distribution 1 (302) and the output probability b′(2,O) obtained from distribution 2 (303).
FIG. 3 exemplifies a one-dimensional observation signal for the descriptive simplicity. In pattern recognition such as speech recognition, a multi-dimensional feature vector is generally used as an observation signal. An output probability distribution is defined as a multidimensional continuous mixture distribution. A Gaussian distribution is often used because of simple calculation. The output probability of the mixture distribution is calculated as the weighted sum of output probabilities of a plurality of Gaussian distributions.
The number of mixture components (number of mixtures) in FIG. 3 is two. In order to build a high performance model, the number of mixture must increase to precisely express the output probability distribution.
The actual output probability of a mixture distribution using, e.g., an diagonal Gaussian distribution is calculated by:
b ′ ( m , 𝕆 ) = ∏ k = 1 K ( 1 2 πσ 2 ( m , k ) ) 1 2 exp ( - 1 2 ∑ k = 1 K ( o ( k ) - μ ( m , k ) ) 2 2 σ 2 ( m , k ) ) ( 1 ) b ( 𝕆 ) = ∑ m = 1 M w ( m ) · b ′ ( m , 𝕆 ) ( 2 ) where
K: the number of dimensions of feature vector (observation signal) used
O={o(1), o(2), . . . , o(K)}: observation signal (K-dimensional vector)
b(O): the output probability of the mixture distribution
b(m,O): the output probability of the distribution m
M: the number of mixtures
w(m): the weight of the distribution m
σ2(m,k): the k-dimensional variance of the distribution m
μ(m,k): the k-dimensional mean of the distribution m
When an output probability is actually calculated on a computer, the logarithmic value B′(m,O) of the weighted output probability is generally calculated by:
B ′ ( m , 𝕆 ) = ln ( w ( m ) · b ′ ( m , 𝕆 ) ) = ln ( w ( m ) ) + 1 2 ∑ k = 1 K ln ( 1 2 πσ 2 ( m , k ) ) - 1 2 ∑ k = 1 K ( o ( k ) - μ ( m , k ) ) 2 σ 2 ( m , k ) = C ( m ) - 1 2 ∑ k = 1 K ( o ( k ) - μ ( m , k ) ) 2 σ 2 ( m , k ) C ( m ) = ln ( w ( m ) ) + 1 2 ∑ k = 1 K ln ( 1 2 πσ 2 ( m , k ) ) ( 3 )
The logarithmic value is used to prevent an underflow, and the computation load of the computer can advantageously be reduced because the term of power calculation in equation (1) is expanded. The constant part (C(m)) independent of the observation signal can be calculated in advance. The logarithmic value B(O) of the output probability of the mixture distribution as the final result can be given by:
B ( 𝕆 ) = ln ( b ( 𝕆 ) ) = ln ( ∑ m = 1 M w ( m ) · b ′ ( m , 𝕆 ) ) = ln ( ∑ m = 1 M exp { ln ( w ( m ) · b ′ ( m , 𝕆 ) ) } ) = ln ( ∑ m = 1 M exp ( B ′ ( m , 𝕆 ) ) ) ( 4 )
In equation (4), after the weighted logarithmic output probability value of each distribution is obtained, the power calculation and the natural logarithmic operation are still necessary to calculate the output probability of the mixture distribution. To simplify the above calculations, the approximation methods of the output probability calculation are disclosed in H. Ney et al., “Phoneme modeling using continuous mixture densities”, Proc. ICASSP88, pp. 437-440, 1988 (to be referred to as Ney hereinafter) and Japanese Patent No. 2983364.
In Ney, the output probability of the mixture distribution is approximated using the maximum output probability of the output probabilities of the respective distributions instead of calculating the sum of the output probabilities of the respective distributions, thereby reducing the calculation amount. That is, in place of equation (2), the output probability of the mixture distribution is calculated by:
b ( 𝕆 ) = max m = 1 M w ( m ) · b ′ ( m , 𝕆 ) ( 5 )
Japanese Patent No. 2983364 discloses an example in which a technique as in Ney is applied to an arc-emission HMM (Mealy machine).
When the approximation of equation (5) is used for equation (4), the logarithmic output probability of the mixture distribution can be simplified as:
B ( 𝕆 ) = ln ( b ( 𝕆 ) ) = ln ( max m = 1 M w ( m ) · b ′ ( m , 𝕆 ) ) = max m = 1 M ln ( w ( m ) · b ′ ( m , 𝕆 ) ) = max m = 1 M B ′ ( m , 𝕆 ) ( 6 )
The above conventional technique is excellent because the computation cost is reduced by the approximation while degradation in recognition accuracy by the approximation errors is little. However, output probability calculation of the mixture distribution HMM still requires a large amount of calculation cost. | {
"pile_set_name": "USPTO Backgrounds"
} |
Wind power is considered one of the cleanest, most environmentally friendly energy sources presently available, and wind turbines have gained increased attention in this regard. A modern wind turbine typically includes a tower, a generator, a gearbox, a nacelle, and one or more rotor blades. The rotor blades capture kinetic energy from wind using known foil principles and transmit the kinetic energy through rotational energy to turn a shaft coupling the rotor blades to a gearbox, or if a gearbox is not used, directly to the generator. The generator then converts the mechanical energy to electrical energy that may be deployed to a utility grid.
Wind turbine rotor blades generally include a body shell formed by two shell halves of a composite laminate material. The shell halves are generally manufactured using molding processes and then coupled together along the corresponding ends of the rotor blade. In general, the body shell is relatively lightweight and has structural properties (e.g., stiffness, buckling resistance and strength) which are not configured to withstand the bending moments and other loads exerted on the rotor blade during operation. In addition, wind turbine blades are becoming increasingly longer in order to produce more power. As a result, the blades must be stiffer and thus heavier so as to mitigate loads on the rotor.
To increase the stiffness, buckling resistance and strength of the rotor blade, the body shell is typically reinforced using one or more structural components (e.g. opposing spar caps with a shear web configured therebetween) that engage the inner surfaces of the shell halves. The spar caps are typically constructed of various materials, including but not limited to glass fiber laminate composites and/or carbon fiber laminate composites. Such materials, however, can be difficult to control, defect prone, and/or highly labor intensive due to handling of the dry and pre-preg fabrics and the challenges of infusing large laminated structures.
As such, modern spar caps may be constructed of pre-fabricated, pre-cured (i.e. pultruded) composites that can be produced in thicker sections, and are less susceptible to defects. Accordingly, the pultruded composites can eliminate various concerns and challenges associated with using dry fabric alone. As used herein, the terms “pultruded composites,” “pultrusions,” “pultruded members” or similar generally encompass reinforced materials (e.g. fibers or woven or braided strands) that are impregnated with a resin and pulled through a stationary die such that the resin cures or undergoes polymerization through added heat or other curing methods. As such, the process of manufacturing pultruded composites is typically characterized by a continuous process of composite materials that produces composite parts having a constant cross-section. A plurality of pultrusions can then be joined together to form the spar caps and/or various other rotor blade components. The thickness of the pultruded material helps to lower the unit cost of the components by increasing the material throughput of the die. In addition, the die shape is simple (i.e. preferably rectangular) to increase the pull rate of material through the die.
Pultruded components, however, are not without certain drawbacks. For example, the thickness of the pultruded components does not easily conform to the aerodynamic profile of the blade. Further, changing the cross-sectional area of the pultruded component to be flexible can increase complexity of the pultrusion process, thereby slowing down the material manufacturing process.
Accordingly, the art is continuously seeking new and improved methods of manufacturing pultruded or belt-pressed rotor blade components, such as spar caps, having one or more areas of variable stiffness such that the components can conform to various locations of the rotor blade. | {
"pile_set_name": "USPTO Backgrounds"
} |
The present disclosure is generally related to image guided medical procedures using an access port. This port-based surgery approach allows a surgeon, or robotic surgical system, to perform a surgical procedure involving tumor resection in which the residual tumor remaining after is minimized, while also minimizing the trauma to the intact white and grey matter of the brain. In such procedures, trauma may occur, for example, due to contact with the access port, mechanical stress to the brain matter, unintentional impact with surgical devices, and/or accidental resection of healthy tissue.
Thus, there is a need for mechanisms to define an appropriate access port path, to minimize trauma when navigating down the path.
Probes for optical measurements of tissue are being developed for a wide variety of applications and modalities, all focused on providing clinicians with details regarding the state of tissue to guide diagnosis or treatments. While the low penetration of light into biological tissue (on the order of 2 mm) restricts the use of optical techniques to surface or near surface measurements, the potential for optical probes to be miniaturized opens the possibility for probes to be combined with endoscopic or catheter-based techniques. This allows for optical measurements to be made in a wide variety of hollow organs (esophagus, colon, lung, etc.) and as a part of many minimally invasive surgical techniques. The optical modalities for which probes have been developed include broadband spectroscopy (ultraviolet, visible, near infrared, and short wave infrared), fluorescence, Raman spectroscopy, optical coherence tomography, photoaccoustic tomography, coherence anti-Stokes Raman spectroscopy, confocal microscopy, among others.
Port-based or corridor surgery is a minimally invasive surgical technique where a port (generally a cylindrical plastic tube open on both ends) is introduced to access the surgical region of interest. Unlike other minimally invasive techniques, such as laparoscopic techniques, the port diameter is larger than the tool diameter, allowing bi-manual tool manipulation within the port. Hence, the tissue region of interest is accessible through the port. The presence of the tissue region of interest at a depth of a few centimeters below the skin surface and accessible through a narrow corridor allows for optical probe measurements to be made on regions of interest in close proximity to the tissue (contact probe within the port) and at a standoff distance from the tissue (stand-off probe position outside of the port).
While a wide variety of optical probes have been developed for numerous modalities, specific design aspects to enable and enhance the use of these probes within port-based surgery have not been developed. These include: the size of the probe, sterilization tolerance, signal enhancing mechanisms, integration with surgical tools, position and orientation tracking, and integration with other optical systems. At present the lack of these features hinders and restricts the use and utility of probes for port-based surgery. Thus there is a need to develop probes with design aspects that may enable and enhance their use within port-based surgery. | {
"pile_set_name": "USPTO Backgrounds"
} |
Field of the Invention
The present invention relates to a security gateway connection in a cellular communication network and in particular to a method and a system for facilitating participation of an intermediary network device in a security gateway communication between at least one base station and a core network portion in a cellular communication network.
Description of Related Art
Common cellular communications networks provide convenient wireless communications services. These services include, for example, cellular telephone services, paging, Internet access, and data transfer services, among others.
Such a common cellular communication network includes a core element and a Radio Access Network (RAN). The core element comprises at least a connectivity gateway and a mobility management function. The Radio Access Network further comprises base stations and respective mobile stations, the client devices. Each of the client devices is typically connected to one of the base stations. This connection needs management of backhaul and core network connectivity, which is usually facilitated by the core element.
Therein, it is in many situations desirable to encrypt communications sent over the network. For example, various government regulations require the use of encryption, even on private networks. Thus, security is a dominant concern in cellular communication networks. Conventional configurations typically employ a hub-and-spoke security implementation whereby the base stations and/or the client devices establish a long-lived IP Security (IPSec) tunnel to the core network portion over which all communications including signaling, voice communications, and data communications are sent. A security gateway may be provided to authenticate users, encrypt communications, and perform other relevant conventional security features, for example by using respective keys.
Common cellular communication networks usually further include intermediary network devices, which perform various types of processing, for example applying various policies, on transmitted messages. Unfortunately, some of this processing may not be possible unless the transmitted messages are decrypted prior to being processed. However, if the intermediary network devices are unable to decrypt encrypted messages, the intermediary network devices may not be able to perform the desired processing. Absent the ability to process the encrypted messages, these intermediary network devices will only be able to apply very basic policies to encrypted messages, which may in turn negatively affect overall network performance or even prevent the effective communication of encrypted messages within the cellular communication method.
US 2011/0231659 A1 discloses a method for out-of-band session key exchange, wherein a source device that plans to participate in one or more encrypted communication sessions with a destination device sends a discovery message towards the destination device. An intermediary device that processes this discovery message requests a master key from the source device. The source verifies that the intermediary device is a trusted device and then sends the intermediary device the requested master key. Prior to transmitting encrypted messages to the destination device, the source device sends session key information, encrypted using the master key, to the intermediary device. The intermediary device uses this session key information to decrypt and process encrypted messages sent as part of the encrypted communication session between the source device and the destination device.
There are further intermediary network devices known, which can inject traffic in a cellular communication network, for example network devices which are designed to improve mobile user experience and optimize resource utilization by performing content caching in order to accelerate downloading of content such as video streams and high-resolution images from the Internet. However, these devices usually cannot be placed near the base stations when an IPsec tunnel is established between the base stations and the core network portion, since the intermediary network device does not see traffic inside the IPsec tunnel and does not possess the respective keys, and, therefore, cannot perform content caching.
Therefore, methods for facilitating participation of a such an intermediary network device in a security gateway communication between at least one base station and a core network portion in a cellular communication network are desirable. | {
"pile_set_name": "USPTO Backgrounds"
} |
This invention relates generally to feeding systems for caged or confined animals such as poultry. More particularly, the invention concerns a feeding system in which feed is continuously agitated and intermixed during delivery and conveyance along a row of cages or other confinement structures, so as to encourage delivery of substantially equal amounts and kinds of feeds to each confined animal.
Large-scale poultry operations utilize sophisticated equipment for maintaining relatively large flocks of poultry in relatively large poultry houses. In egg producing or layer operations, the birds are normally confined in cages so that food and water can be delivered economically and in accurately rationed amounts, as well as at desired intervals of time. Moreover, these cages are generally constructed and arrayed so as to facilitate feeding, and, in layer operations, egg collection, by devices which travel generally linearly along linearly arrayed rows of cages. One particularly advantageous cage arrangement takes the form of linearly arranged cages stacked in a stepped-back pyramidal array, as shown for example in U.S. Pat. No. 4,060,055.
When the birds are properly confined and fed, high flock performance levels can be achieved and maintained. For example, a maximum number of eggs can be contained from the laying hens while utilizing a minimum amount of food and water. Such considerations are important to the economic viability of a large-scale poultry operation.
The mechanized delivery of feed in such poultry operations is usually accomplished by a feed conveyor system having a series of feed delivery conduits and feed troughs extending past the face of each row of cages. Within these troughs and conduits are located feed conveyor or feed carrying elements, which may take various forms.
Some such systems use a helical, auger-like coil element of extended length as a driver element. As this helical or auger element is rotated, feed is moved along the associated conduits and troughs with an auger motion, but without axial displacement of the coil element or auger. Such devices are shown for example in U.S. Pat. Nos. 3,918,405 and 3,893,423. Other forms of feed conveying devices have also been utilized in the prior art. In a variation on the above arrangement, a similar helical coil is driven axially, but without rotation through a series of conduits and/or feed troughs, as shown in U.S. Pat. No. 4,495,894 to Swartzendruber. Advantageously, this arrangement permits the relatively flexible coil or helical element to be readily driven around .[.corner.]. .Iadd.corners.Iaddend., bends or the like so that a continuous or endless such element may be in effect looped around a path to deliver feed to oppositely facing or back-to-back rows of cages.
As indicated above, feed rations which are accurate and uniform both in quantity and quality are to be repeatedly delivered to each poultry-containing cage. That is, it is desirable that each bird receive a certain amount of each constituent in the feed mix, and that the amounts of each constituent are not varied excessively throughout the delivered rations. However, since the varying feed constituents have different sizes and masses, the heavier or more dense feed constituents will tend to fall to the bottom of the conveyor or trough as the feed is advanced. Likewise, the birds will tend to pick off the upper layers of feed from the trough, such that the lighter constituents may tend to be picked over by the birds at or near the upstream or delivery end of the conveyor system prior to reaching birds downstream.
Accordingly, two additional factors are also desirable in a delivery system. Firstly, the birds should be prevented from picking over the feed until the feed has been delivered throughout the row or rows of cages serviced by a given endless conveyor or conveyor loop. Secondly, the feed should continue to be agitated during delivery to maintain a relatively uniform mix of feed delivered to each cage, and prevent heavier or more dense constituents from falling into the bottom of the trough or conveyor. | {
"pile_set_name": "USPTO Backgrounds"
} |
Shrimp are typically gathered for marketing by means of shrimp trawls which are pulled through the water, typically along the bottom of a body of water by shrimp boats or by other suitable means. After the shrimp are caught they are typically stored in ice or in other conditions of cold storage until they can be transported to a shrimp processing facility. At the shrimp processing facility the shrimp may be packed in a heads-on condition or in a headless condition for transportation to a marketing facility or to the ultimate consumer. The sales price of shrimp is decreased materially by the various handling processes that are employed in grading and subsequently deheading the shrimp or deheading and then grading them for size and quality.
Prior to packing the fresh caught shrimp in ice in the cargo holds of shrimp trawlers, it is desirable to accomplish grading of the shrimp so that they may be sold and shipped without significant further handling. Such on board grading of shrimp is ordinarily not practical since most shrimp grading machines are of such large dimension that they cannot be efficiently mounted on a typical shrimp trawler. Moreover, shrimp grading machines are typically of sufficiently expensive nature that it is impractical to consider locating them on board shrimp trawlers. Although in many cases fresh caught shrimp are graded by manual operations on board shrimp trawlers for the purpose of protecting the catch by immediate cooling with ice to thus enhance the storage life thereof, manual shrimp grading operations can only be conducted if the volume of shrimp being caught is fairly low. In fact it has been determined that only approximately 10% of the shrimp being caught are manually graded and/or deheaded. Further, manual grading operations during shrimp catching and on board processing activities significantly enhances the cost of the shrimp that these activities are generally considered impractical. It is considered desirable therefore to place on board shrimp trawlers and other such vessels a shrimp grading machine of sufficiently small dimension and of sufficiently low cost as to be commercially acceptable for most shrimp trawlers. | {
"pile_set_name": "USPTO Backgrounds"
} |
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