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Most vehicle doors provided on a majority of passenger and truck type vehicles include vertically shiftable door latch lock actuators shiftable between upper and lower active and inactive positions, respectively. Further, although it is the usual custom of many drivers to downwardly depress the lock actuator upon entrance into a vehicle thereby providing additonal assurance against unintentional opening of the vehicle door as a result of impact, some drivers and passengers only depress the lock actuators of the doors of a vehicle when exiting from the vehicle in order to prevent the latter from being stolen. Accordingly, in many cases the door latch lock actuators of vehicles are not in the active positions thereof when an accident occurs and the doors of the vehicle are more likely to be jarred open as a result of impact during an accident. Accordingly, many vehicle drivers and passengers are thrown from passenger vehicles and the like as the result of impact during an accident and are more severely injured than they would have been if the doors of the vehicle had not opened on impact and they were thereby contained within the vehicle throughout the accident.
Accordingly, a need exists for a mechanism whereby the door latch lock actuators of passenger vehicles and the like may be automatically depressed in the event of impact. Various types of inertia operated mechanisms have been heretofore designed for this purpose and previously patented devices of this type are disclosed in U.S. Pat. Nos. 2,389,315, 2,864,641, 3,066,964, 3,453,015, 3,719,248 and 3,799,596. | {
"pile_set_name": "USPTO Backgrounds"
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The invention relates to a plug screwing-in device for barrels or drums.
Barrels and drums to be filled with liquids are, in a known manner, supplied with screwed-on plugs. It is, therefore, necessary to remove these plugs and screw them on again after filling. The barrels must be precisely aligned on a supply belt or the like of the filling mechanism, because there is otherwise a risk of the liquid flowing over the barrel and not into the bunghole. The opening and closing of bungholes is very labour-consuming in the case of the known filling mechanisms.
For closing the filling opening of a barrel or the like with the aid of a device for inserting and fixing a plug in the opening, a closing device is known in which both the device for inserting the plug and also the position determining device must be spaced from one another in such a way that they are freely movable upwards and downwards, as well as in accordance with polar coordinates with respect to a fixed point in a plane perpendicular to the upwardly an downwardly directed movement. In addition, this known device has a gripping device in order to prevent the free movement of the devices for inserting the plug and for determining the position. Furthermore, a drive mechanism is provided, which is suitable for the plug insertion and positioning, when the gripping device prevents the free movement, only in a linear manner and necessarily by a distance corresponding to that between the two devices. This closing device has a very large size. In order to obtain adequate stength for the precise mounting of the movable components, it is necessary for the construction to be very complicated. In addition, the energy requirement for operating this closing device is very great because on centering, the complete frame must always be pivoted about an axis on the support device (DOS No. 18 17 237).
In addition, a further known cover closing and container filling device has a very complicated construction and is very complicated to use (U.S. Pat. No. 29 83 089).
Furthermore, a device for closing containers with an eccentrically arranged spout is known, which is characterized by a prime mover, which can be moved between an inoperative position and an operative position in which a centering device carried by this prime mover engages in the periphery of the container cover wall, which has an eccentric spout in such a way that a rotary output shaft of the prime mover is brought and held in a position coaxial to the container. A scanning device which is held eccentrically by the shaft and as part of the latter is displaceable therewith about a periphery, whose centre point is located on the container axis and whose radius is equal to the spacing between the spout axis and the container axis, up to an engagement position with the spout, and by a sealing head held eccentrically by the shaft in a coaxial position to the scanning device and displaceable along its own axis between an inoperative position and an operative position in which there is engagement with the spout. This device permits the closing of containers with eccentric spouts, the position of the spout being scanned with a device which facilitates and accelerates said scanning operation. At the same time a further device ensures that the complete working cycle of the device takes place completely automatically. However, in order to perform all these functions, the known device has a plurality of complicated components (DOS No. 22 10 753).
Another known device for fitting screwcaps to the bungholes of barrels, with an air or beam vertically movable by a lifting device and pivotable about a vertical axis and with a centering device, as well as a closing device which, by pivoting the arm or beam, can be successively brought over the bunghole of a barrel, is constructed in such a way that the centering device is detachably connected to the arm by means of a receiving flange and on the latter is provided a holding tube with joints for detecting fingers on the outer wall, the shanks of said fingers being guided through openings in the holding tube casing and held together by means of an elastic ring of rubber or the like and whose surface portions remote from the holding tube are risingly convex towards the centre axis of said tube and with guide pins arranged coaxially to the centre axis of the tube, that centrally to the holding tube a centering mandrel can be vertically moved up to engagement with the shanks of the detecting fingers through an opening in the receiving flange by means of a pneumatically or hydraulically acting lifting cylinder, and that the closing device has a suction head for exposing the barrel closure cover to a suction action and a screw head for screwing said cover on to the thread of the bunghole support located on the bunghole on which is arranged an end portion of a receiving tube, whose other end portion is fixed to a rotary drive shaft. Such a device is intended to make it possible not only to position the closing cover on the bunghole after filling the vessel and then screw it down, but also to bring about the necessary motion and force transfer processes by means of hydraulically or pneumatically acting control elements without using long and difficultly manufacturable threaded spindles or the like, so that even with small constructional sizes high power levels can be transferred (DAS No. 25 40 864). | {
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This invention relates to a trailer-mounted sand hopper and is particularly useful for transporting the sand hoppers to isolated construction sites without necessitating the use of specialized rigging or lifting equipment.
Large sand hoppers for storage of sand for use in delivering sand for making concrete are currently transported to construction sites on flatbed trailers. They are generally transported in the upright or vertical position and are lifted from the trailer by means of a crane or cherry picker. The transporting trailer is moved into the proximate location for placement of the sand hopper. The crane then lifts the sand hopper from the flatbed trailer and places it in its final location on the construction site.
Thus, existing methods require the utilization of a separate crane and entail considerable hours of labor to position the sand hopper at the construction site. Additionally, more personnel are necessary to facilitate the removal of the hopper from the flatbed trailer. There must be a driver for the truck transporting the hopper on the trailer, there must be a crane operator, and at least two safety personnel during the rigging and removal procedure.
The advantages of the present invention enable the sand hopper to be placed at a specified location at the construction site by two men in three and one-half minutes or less. There is no need for a crane and all the extra equipment associated with the previous devices and methods for unloading the sand hopper. | {
"pile_set_name": "USPTO Backgrounds"
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People are utilizing electronic devices for an increasing variety of tasks. With the increase in utilization comes an interest in improving the ways in which users interact with these devices. One approach to enabling a user to provide input to an electronic device involves monitoring a gaze direction with respect to a user device, such that the user can provide input based on where the user is looking. Conventional approaches for determining where a user is looking involve tracking motion of the user's eyes over time. This typically involves an expensive set of electronics positioned in a stationary way in order to provide an acceptable level of accuracy. These approaches, however, are generally not accurate enough to provide for fine control of an element such as a cursor of an interface, particularly for a relatively small portable device with a relatively small display screen. The approaches also tend to be more expensive than is practical for many consumer devices. Further still, small portable devices can be held in a user's hand and thus can be subject to small movements that can negatively impact the accuracy of these approaches. | {
"pile_set_name": "USPTO Backgrounds"
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A 5G network, namely, a new radio (NR) network, aims to support higher system performance, including support of different services, different deployment scenarios, and different spectrums. Different services include an enhanced mobile broadband (eMBB) service, a machine type communication (MTC) service, an ultra-reliable and low latency communications (URLLC) service, a Multimedia Broadcast Multicast Service (MBMS), a positioning service, and the like. Different deployment scenarios include an indoor hotspot scenario, a dense urban scenario, a suburban scenario, an urban macro coverage scenario, a high-speed railway scenario, and the like. 5G supports a spectrum range up to 100 gigahertz (GHz), a primary frequency band is lower than or equal to 6 GHz, and a secondary frequency band is higher than 6 GHz.
Different services, different deployment scenarios, and different spectrum have different features, and their respective requirements for system parameters (also referred to as numerology) are different. To support, with high performance, different services, different deployment scenarios, and different spectrum, 5G supports a plurality of sets of system parameters. For example, 5G supports different subcarrier spacings, the different subcarrier spacings are corresponding to different system parameters, and a same subcarrier spacing may support different subframe lengths. Currently, the subframe length may also be referred to as a transmission time interval (TTI) length, or the subframe length may also be referred to as a transmission time unit (TTU) length. A relatively small subframe length such as a subframe length less than 1 millisecond (ms) may be used for a low latency service, for example, URLLC. A relatively large subframe length such as a subframe length of 1 ms may be used for a service whose latency requirement is not high, a service whose data packet size is relatively large, or the like, for example, eMBB.
How to design synchronization signals corresponding to different subframe lengths in a 5G communications network is a problem that needs to be resolved urgently. | {
"pile_set_name": "USPTO Backgrounds"
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Field of the Invention
This invention relates to an infrared sensor for the non-contact measurement of the temperature of a given object and a method for the production thereof. More particularly, it relates to an infrared temperature-sensing film with an electrode and a method for the production thereof. | {
"pile_set_name": "USPTO Backgrounds"
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Certain medications are more effective when they are administered to a patient by injection. One such medical condition which shows improved treatment with several daily injections is the treatment of diabetes with insulin. Unfortunately, the required multiple injections not only cause physical and psychological pain, but also raise the possibility of infection.
Various pump devices have been proposed to either slowly administer a continuous flow of insulin or provide several intermittent injections over time. These devices generally use a needle, which is inserted through the skin. Due to the threat of infection, the needle must be discarded after use, and a new needle inserted in a different location each day. To meet these problems, catheters have been designed for implantation through the skin to deliver the insulin. Unfortunately, such catheters have their own shortcomings and can sometimes become infected, thrombose or become clogged, reducing or stopping the flow of insulin. Occasionally, without any apparent reason, the subcutaneous tissue of a diabetic patient will begin to degrade and inactivate insulin, reducing its usefulness.
To solve these problems, implantable insulin infusion devices have been proposed. Such devices are implanted under the skin, with a tube leading into the peritoneal cavity. This avoids the difficulties of insulin inactivation by subcutaneous tissue, clogging and the threat of thrombosis. It has also been found that insulin administered intraperitoneally is quickly carried to the liver, the natural delivery point for insulin produced by the pancreas. This form of administration also has the side benefit of minimizing ketosis and hyperglycemia.
The devices which have been proposed for such administration have a pierceable septum which is either outside the patient or is located immediately below the surface of the patient's skin. However, in attempting to solve one problem, a new problem is created. After the pierceable septum of such a device becomes worn through use, it must be surgically removed and replaced, thereby exposing the patient to pain, discomfort and possible infection. No means is provided for replacing the septum after it has become worn through repeated injections. Nor is any means provided to protect the patient from infection during such a replacement.
Accordingly, it would be desirable to provide a device and medication delivery system which avoids the shortcomings of the prior art, yet provides for a safe and effective way of delivering a medication to the patient percutaneously. Such a device and system should have parts which can be easily and safely replaced as they become worn through use and should also protect the patient against infection while a part is being replaced. Means should also be provided for connecting with a pump for continuous administration of medication. The present invention meets these desires. | {
"pile_set_name": "USPTO Backgrounds"
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In the related art, for example, a battery module formed by arranging a plurality of battery cells such as lithium ion secondary batteries or the like is known. In such a battery module, by enclosing an array body of battery cells by a retaining tool such as a metal plate or the like to be restricted with a constant load, variation in properties such as internal resistance or the like in the battery cells is suppressed. For example, in a battery pack disclosed in Patent Literature 1, a metal band having bent portions at both ends thereof is fixed to an end plate, and a battery block is restricted by the end plate in a stacking direction. In such a battery module, in order to prevent damage to a retaining member due to expansion of the battery cells, an elastic body such as rubber or the like may be interposed between the array body and an end plate of the retaining member.
In addition, a harness used for detection of a voltage or the like of each of the battery cells is assembled to the battery module. For example, in the battery pack disclosed in Patent Literature 2, by holding connectors including voltage detection terminals by a holding member and attaching the holding member to a battery group, the connectors are collectively electrically connected to electrode terminals of the battery cells. | {
"pile_set_name": "USPTO Backgrounds"
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Membrane biogenesis is essential for cell growth and differentiation. During membrane biogenesis in eukaryotic cells, newly synthesized phospholipids must be transported from their sites of synthesis to their sites of function. Vesicular traffic in eukaryotic cells is characterized by two steps of membrane rearrangement: the formation of vesicles from donor membranes and fusion of these vesicles with acceptor membranes. With respect to vesicle formation, several of the cytosolic proteins implicated in budding and fission have been identified. These stimulate the formation of constitutive secretory vesicles and immature secretory granules from the trans-Golgi network.
Phosphatidylinositol transfer protein (PITP) is a member of a diverse set of cytosolic lipid transfer proteins that are distinguished by their ability to transfer phospholipids between membranes in vitro and to take part in secretory vesicle formation (Wirtz, K. W. A. (1991) Ann. Rev. Biochem. 60:73-99; Ohashi, M. et al. (1995) Nature 377:544-547). PITP has been purified from mammals, plants, fungi and bacteria (Wirtz, K. W. A. (1991) supra).
PITPs have raised considerable interest because of their proposed roles in the phosphoinositide cycle and the ATP-dependent, Ca.sup.2+ -activated secretory process (Thomas, G. M. et al. (1993) Cell 74:919-928; Hay, J. C. and Martin, T. F. J. (1993) Nature 366:572-575). Furthermore, mammalian PITPs have a yeast counterpart, protein SEC14p, which is an essential factor in the secretory vesicle flow from the trans-Golgi network to the plasma membrane (Bankaitis et al. (1989) J. Cell Biol. 108:1271-1281; Bankaitis et al. (1990) Nature 347:561-562, and shares no sequence homologies with the mammalian PITPs.
In mammals, two isoforms of PITP have been identified. Human testis PITP.alpha. has 78% identity with human brain PITP.beta. (Dickeson, S. K., et al. (1994) Gene 142:301-305; Tanaka S. et al. (1995) Biochim. Biophys. Acta 1259:199-202).
A PITP homologue has been identified in an insect retinal protein, Drosophila retinal degradation B (rdgB) protein (Vihtelic, T. S. et al. (1991) Genetics 127:761-768). Amino acid sequence identity is 40% between human PITP.alpha. and the 280 amino acid residue N-terninal domain of the fly protein. The N-terninal domain in fly rdgB protein has PI transfer activity, an additional 803 residue C-terminal domain of rdgB is critical for proper protein function in flies (Vihtelic, T. S. et al. (1991) supra). Mutations present in the carboxy-terminal domain result in a truncated peptide and flies carrying the rdgB mutations undergo light-enhanced retinal degradation (Vihtelic et al. (1991) supra).
The yeast (Saccharomyces cerevisiae) PITP is essential for cell growth (budding) (Bankaitis et al. (1990) supra) and is presumed to be critical for membrane synthesis during budding as well as being a component of the PI second messenger system that is associated with the cell cycle. In support of the latter role, it has been suggested that yeast PITP synergizes with a type I PI-4-phosphate 5-kinase to promote priming of dense-core secretory granules for Ca.sup.2+ -regulated fusion to the plasma membrane and that a significant aspect of the ATP requirement in vesicle trafficking may be dedicated to phosphatidylinositolbisphosphate (PIP.sub.2) synthesis (Hay, J. C. and Martin, T. F. J. (1995) supra).
Human PITP.alpha. is also required for the PI-phospholipase C-mediated hydrolysis of PIP.sub.2 in response to plasma membrane epidermal growth factor receptor stimulation (Kauffinan-Zeh, A. et al. (1995) Science 268:1188-1190). Kinetic data argues strongly that PITP recruits PI from intracellular compartments, presents PI to PI 4-kinases in both the plasma membrane and the nucleus, and is a cofactor in inositol lipid signaling (Cunningham, E. et al. (1995) Curr. Biol. 5:775-783; Capitani, S. et al. (1991) Adv. Enzyme Reg. 31:399-416).
Mutation of rat PITP.alpha. at Thr59, which can be phosphorylated by protein kinase C (PK-C), regulates the binding affinity of PITP for PI, but not for phosphatidylcholine (PC) (Alb, J. G. et al. (1995) Proc. Natl. Acad. Sci. USA 92:8826-8830). Covalent modification of other residues within PITP has not yet been reported.
The etiology of numerous human diseases and disorders can be attributed to defects in the trafficking of proteins to organelles or the cell surface. Defects in the trafficking of membrane-bound receptors and ion channels are associated with cystic fibrosis, glucose-galactose malabsorption syndrome, hypercholesterolemia, and forms of diabetes mellitus. Abnormal hormonal secretion is linked to disorders including diabetes insipidus, hyper- and hypoglycemia, Grave's disease and goiter, and Cushing's and Addison's diseases.
The product of phospholipase C.beta.-mediated PI hydrolysis, inositol trisphosphate (InsP.sub.3), is associated with a number of cellular responses in diverse tissue types. These include glycogen breakdown in the liver, amylase and insulin secretion in the pancreas, smooth muscle contraction, histamine secretion from mast cells, and serotonin and platelet-derived growth factor secretion from blood platelets (McCance, K. L. and Heuther, S. (1994) Pathophysiology (2nd Ed.) Mosby-Year Book, Inc. St. Louis, Mo. p. 20).
The critical role of InsP.sub.3 as a second messenger in the cell cycle suggests that decreasing the levels of membrane-associated PI within neoplastic tissue will contribute to the availability of PI as a source for InsP.sub.3 and prevent neoplastic growth stimulated by Ca.sup.2+ release from intracellular stores. In parallel, levels of intracellular diacylglycerol, the lipid product of PI hydrolysis, would be decreased and activation of the PK-C-mediated kinase cascade would be downregulated (Berridge, M. J. (1995) BioEssays 17:491-500).
The discovery of a new human phosphatidylinositol transfer protein and the polynucleotides encoding it satisfies a need in the art by providing new compositions which are useful in the diagnosis, prevention and treatment of disorders associated with abnormal vesicle trafficking and neoplastic disorders. | {
"pile_set_name": "USPTO Backgrounds"
} |
Textile based heat-bonding products are now widely used in the clothing industry and make it possible for example to manufacture linings or reinforcement fabrics which can be heat sealed.
A number of methods and apparatus for manufacturing such products by coating are known.
A first category of methods, called HOT MELT methods, consists in directly applying a molten thermoplastic polymer mass on the textile supporting base. For example, for implementing this method, a polymer mass is brought to a temperature higher than its melting temperature, it is distributed in the cavities of a photogravure cylinder (hollow engraved), the surface of this cylinder is scraped and it is placed in contact with the textile supporting base on which the polymer spots are to be applied.
These methods have a number of drawbacks which have prevented them up to now from developing despite the advantages which they offer.
In fact, this method does not make it possible to obtain quality spot coating. The action of the scraper does not completely eliminate the traces of polymer on the smooth surfaces of the cylinder. Hot polymer residues remain on these surfaces and come into contact with the textile base. In some cases, the textile supporting base, in contact with the photogravure cylinder, loses fibres which adhere to the cylinder, contribute to its clogging up and may even deflect the scraper from the cylinder which produces a continuous adhesive polymer layer which is then deposited on the textile base. The quality of the product obtained is low and ill suited to use in the clothing field.
During use of this method, the polymer mass contained in the cavities, when placed in contact with the textile supporting base, adheres thereto, which contributes to emptying the cavities and depositing of the spots on the textile base. Aerated textiles, or those with gaps or empty spaces, do not provide uniform adherence of the polymer contained in all the cavities. Some of them are then not suitably emptied which leads to coating defects.
A method is further known of manufacturing thermoadhesive textile products in which the adhesive is deposited on the textile base in the form of spots of powder or of aqueous solution. After such deposition, the whole is brought to a high temperature which melts the polymer and causes it to adhere to the textile base.
The patent FR 2 586 717 describes a method of this latter type in which drops of a heat-bonding material dispersion are first of all deposited on an anti-adhesive transfer base; then the drops on the transfer base are heated and the drops of adhesive are placed in contact with the textile base. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
This invention relates to heavy equipment turntables. The present invention is particularly directed towards a mobile truck turntable with hydraulic or air operation and control means.
2. Description of the Prior Art
Past art patents were examined from a search conducted in the following classes and subclasses:
104/44 and 410/1.
The patents which appeared to be most applicable to my invention included:
The Freshwater et al patent issued on Feb. 27, 1923, U.S. Pat. No. 1,446,498, depicts an improvement to turntables.
U.S. Pat. No. 1,449,767, dated Mar. 27, 1923, was issued to MacLean for a "Portable Turntable".
A patent issued to Miner on May 8, 1923, U.S. Pat. No. 1,454,482, shows another "Portable Turntable".
On Jan. 15, 1924, Topping was issued U.S. Pat. No. 1,480,872, which discloses a device for turning vehicles around on a fixed center.
The patent issued on Mar. 24, 1931, to Koehler, U.S. Pat. No. 1,797,830, shows a turntable designed to turn cars in areas of limited space.
The Axman patent dated Jan. 3, 1961, U.S. Pat. No. 2,967,045, depicts a turntable attachment for tractors
A patent issued to Mengel on June 14, 1966, patent unloading and distributing material.
The Sorg patent, dated Oct 27, 1970, U.S. Pat. No. 3,536,214, was issued for "Turntable Trailer Apparatus".
On Sept. 2, 1986, Astill was issued U.S. Pat. No. 4,609,111 on a rotatable stand for displaying objects.
To the best of my knowledge, the afore listed patents disclose devices most nearly in the nature f my invention. However, my invention is considerably different in design, structure, and operational mechanics from the devices of the past-art patent disclosures. | {
"pile_set_name": "USPTO Backgrounds"
} |
The present invention relates to a device functioning as a nozzle for mixing nitrous oxide with fuel for maximum horsepower in a racing car engine. More particularly the present invention, hereinafter referred to as the laminar flow nozzle, relates to a nozzle comprised of only one integral component.
In our invention, there are three protuberances integrally and physically part of a nozzle chamber. These protuberances are designated as cylindrical conduit components. One such cylindrical conduit component contains liquid fuel, while the other transports nitrous oxide in the preferred embodiment. In other embodiments other gaseous oxidizers are suitable as well.
Each of these two cylindrical conduit comprises means for a stream of gas or fuel to flow into the nozzle chamber. In the preferred embodiment, each cylindrical conduit specifically contains one integrally formed channel through which either vaporized fuel or an oxidizer flow through the nozzle. Both channels, continue through nozzle chamber in a manner which becomes increasingly parallel.
The channels terminate at the second, opposite side of the nozzle chamber. A third integral threaded cylindrical conduit at this second opposite end contains an emitter and its orifice. Gas enters through the emitter and mixes with droplet fuel in a contiguous dispersing chamber. From the dispersing chamber the combined gas and fuel enter the engine manifold. This third conduit component is physically a part of the nozzle chamber and comprises protuberance-like characteristics. The emitter and conduits are well known to those versed in this art.
Our laminar flow nozzles can be any size, length, shape, curvature, depth or length within the scope of this invention. However, in the preferred embodiment, the channels feeding the fuel and nitrous oxide to the opposite, second end of the nozzle must (i) approach each other in a near linear fashion; and (ii)comprise physically internal components of the nozzle.
Our novel nozzle is extremely lightweight which makes it ideal for racing vehicles. Combustion of fuel and nitrous oxide is less turbulent, resulting in a higher burst of horsepower. There has been a long-standing need in the racing car industry for a lightweight nozzle which is inexpensive and fits most manifolds and solenoids. The fit and configurations of the manifolds and solenoids, as well as their attachments to the remainder of the vehicle, are well known to those skilled in the art.
Nitrous oxide adds more oxygen to the engine, thus making fuel combustion more complete. In the prior art, if there is insufficient fuel to burn, however, nitrous oxide can damage the engine. Our invention's consistent flow of fuel prevents this phenomenon from occurring. More horsepower is created by our invention because of less turbulence and empirical loss of energy due to shock waves.
The cylindrical conduit components in the preferred embodiment are rigid. In the preferred embodiment the nozzle is generally comprised of aluminum because it is lightweight, withstands stress, and is easy to machine drill by those skilled in this particular art. Other suitable materials for nozzles include stainless steel, copper or brass.
In the preferred embodiment, 118 octane Torco.TM. is the fuel of choice. Alternatives include lower octane fuels obtained from the ubiquitous "gasoline station." Octane readings of approximately 116 to 112 are recommended, but approximately 112 to 118 octane readings comprise an acceptable range. One hundred per cent ethyl alcohol is also appropriate. Octane numbers ranging from approximately 112 to 116 are recommended, but for the preferred embodiment the most desirable and effective fuel is 118 octane Torco.TM. racing fuel.
In the preferred embodiment, introduction of nitrous oxide adds oxygen to the engine, so that fuel oxidation(combustion) is more thorough and complete inside the nozzle tip. Nitrogen provides a stable chemical environment for the oxygen prior to combustion. Excessive oxygen in the engine will cause undesirable heat, stress the pistons, and eventually detonate. Our invention also adds additional fuel through our novel nozzle, which smoothly and predictably provides additional fuel by a more linear flow.
Air can serve as an alternative oxidizer. However, the advantage of using nitrous oxide is the resulting control of oxygen levels for complete fuel combustion. The relative linear approach of combining the flow of nitrous oxide and fuel at the nozzle tip is important because: (i) otherwise nitrous oxide will traverse the fuel directly to the cylinders, causing overheating of the motor; and (ii) the exact mixture must be maintained to balance increased horsepower with minimal temperature increases in the engine.
Fuel pressure ratings for our nozzle varies on motors using fuel injection systems. The fuel pressure to the nozzle should range from approximately 32 to 42 pounds per square inch (psi). On motors using carburetors, the recommended fuel pressure to the nozzle ranges from approximately six (6) to six and one/half (61/2) pounds per square inch.
Our invention includes the following, but the list is not necessarily inclusive:
(i) integral threaded means as cylindrical conduit components of the nozzle, PA1 (ii) near-laminar flow through the nozzle chamber, PA1 (iii) combustion of vaporized fuel and oxidizer, which is initiated inside specialized portions of the nozzle, PA1 (iv) the acute angle of approximately 15 degrees or less at which the nitrous oxide and fuel physically approach each other prior to physically mixing, PA1 (v) the one-piece design of the nozzle. It appears that prior art racing car nozzles have screw-like detachable means penetrating the exterior of the nozzle chamber to connect the nozzle chamber to fuel and nitrous oxide. Empirically this results in severe turbulence when the fuel and gas meet. PA1 (vi) in our preferred embodiment, our nozzle with the above characteristics, in combination with a particular fuel recently developed for high speed vehicle racing. PA1 (vii) our methodology of producing orifices and channels within the nozzle which produce channels which are straight and smooth. The operator versed in the art uses a programmed machine on a nozzle with less curvature in the protruding threaded components. PA1 (viii) our methodology of producing a unicomponent nozzle. PA1 (ix) use of jets to control the amounts of oxidizer and fuel entering the nozzle. PA1 (1) that an oxidizer, such as nitrous oxide, and fuel approach at an acute angle of approximately 15 degrees or less to create nearlaminar flow at the second opposite end of the nozzle; PA1 (2) cylindrical conduits and a chamber physically comprise one integral nozzle; PA1 (3) in the preferred embodiment, in combination with the above described nozzle the fuel should be Torco.TM. 118.sub.r with the physical characteristics described infra; PA1 (4) the methodology of producing orifices and channels should comprise production of orifices and channels with our nozzle, which produce less turbulence by using a computer programmed machine.
In most prior art, the angle between the incoming fuel and oxidizer is approximately between 25 and 35 degrees. This causes the oxidizing gas to blow through the fuel without adequate mixing. Our laminar flow nozzle decreases this angle and allows fuel and gaseous oxidizer to mix more completely.
In the preferred embodiment for racing vehicles, a fuel pump physically separate from the fuel regulator is useful. Fuel pressure recommended ratings for the preferred embodiment range for carbureted engines from approximately six to six and one-half pounds per square inch(psi). Carburetor motors mix fuel and air above the motor in an apparatus physically connected to the motor. This combination flows through the manifold to the cylinders within the motor.
In all vehicles there is a tank to hold the fuel. To move the fuel to the motor a pump is required. The pump moves the fuel from the tank through a feed line to the motor. There is a regulator on this feed line. The regulator will adjust the pressure or amount of fuel delivered to the motor.
The temperature of the nitrous oxide (NO2) within the nozzle, ranges between approximately minus 100 degrees F. to minus 112 degrees F. as it flows through a feed line to the nozzle. There is no need to regulate the temperature: At 87 degrees F. nitrous oxide spontaneously transforms to gas.
The nitrous oxide is held in a bottle or feed line, which leads to the nozzle. The ideal temperature of nitrous oxide within this bottle is 87 degrees F. At 87 degrees F. this bottle is pressurized to the recommended range of approximately 900-1000 psi.
Ratios of vaporized fuel to nitrous oxide in the preferred embodiment range from between approximately 1.25 parts vaporized fuel to 1.25 parts nitrous oxide, volume per volume. Another suitable ratio is 1.00 parts vaporized fuel to 1.25 nitrous oxide, volume per volume, depending upon the requirement for additional horsepower.
Analogous nozzles from the prior art for racing car engines are generally comprised of separate physical components. Generally two separate metal cylindrical conduits with a threaded surface lead into the nozzle. Each component is fastened to the nozzle chamber by a threaded screw means.
In this prior art, each of two conduits contain a single channel for gas or fuel flow. They both enter from the first, upper side of the nozzle chamber, but at an angle which forms a "y" shaped configuration within the nozzle chamber. The angle thus formed ranges from approximately 25 degrees to 35 degrees.
This range empirically correlates with greater turbulence when the gas and fuel spontaneously combust within or near the nozzle. Experiments and field tests also support these figures. Moreover, expensive modification of nozzle mounts on the manifold and solenoids occur with prior art prototypes within this angle of convergence range. Combustion at this range of angles 25 to 35 degrees, after convergence in the upper section of the nozzle, creates turbulence and eddies.
In the prior art, also attached at the opposite, second side of the nozzle's chamber is a third, physically separate conduit component. This conduit component further comprises an interior channel which carries the mixture of gases through emitter components to the engine manifold. This third conduit is also attached by a threaded means to the body of the nozzle, and generally must be applied by tightening with a screw wrench or similar tool.
The Fogger.TM.r, manufactured by Nitrous Oxide Systems, Inc. (NOS) generates horsepower which is proportional to the amount of vaporized fuel oxidized on each power stroke of a piston.
The Fogger.TM.r, also comprises separate cylindrical conduits for transporting gases into the nozzle chamber. This means more weight and/or breakage when attaching each conduit to the nozzle chamber. Most significantly, unlike our novel invention, the angle between the two entry cylindrical conduits channels is approximately 25 to 35 degrees.
The Power Wing.TM. nozzle manufactured by The Nitrous Works can be retrospectively fitted to a 1/8-NPT (normal pipe tap) port. As with the previous prior art prototypes, supra, there are at least three physically separate cylindrical conduits attached to the main nozzle by screwlike means. One-eight NPT is the size of the aperture required to screw the nozzle into the manifold.
In the prior art, each cylindrical conduit, once fitted to the nozzle, carries vaporized fuel and nitrous oxide. The channels or tubing converge at a wide angle, ranging from approximately 25 degrees to 35 degrees. This angle experimentally correlates with greater turbulence when gas and fuel combust near the upper, first side of the nozzle chamber. Moreover, modification of nozzle mounts on the manifold and solenoids are often required.
In the prior art, screwlike means attaching these cylindrical conduit components to the nozzle are easily broken during the tightening process. Moreover, a plurality of such additional attachments add considerable weight to the engine system. There is also difficulty drilling orifices and channels directly into a nozzle. In our invention it is easier to drill such orifices due to relative lack of curvature of the conduit components, and which are integrally attached to the nozzle chamber.
Some prior art conduits are lined with metal tubing. The rationale was the tubing facilitated an even flow of gas and fuel. Without physical separation by inert tubes made of copper or brass, in the prior art, gases combust prematurely at the first upper end of the nozzle chamber. This premature exposure lessens the overall potential horsepower from the rapidly increasing pressure and energy from combustion.
In the prior art, operators drilled orifices from the inlet ports on the upper first side of the nozzle., to the outlet for mixed gas and fuel at the second lower end of the nozzle. The difficulty arises when operators could not drill straight, regular orifices and channels with an angle of merge, e.g., 25 to 35 degrees, as described supra. Often these operators must drill from the first upper and second lower ends of the nozzle simultaneously to achieve channels which are contiguous.
This prior art approach results in counterproductive turbulence throughout the nozzle channels. Our invention incorporates the integral threaded conduits, reduces the angle of merge and comprises orifices with a wider diameter and channels which have no physical irregularities.
The Billet Atomizer.TM., also manufactured by The Nitrous Works, comprises a plate system for the area of turbulence located at the angle where the two channels converge. The billet atomizer has at least three physically separate cylindrical conduit components with disadvantages already discussed supra. The angle of convergence of the two gases is also very wide, resulting in more turbulence and premature combustion.
U.S. Pat. No. 5,699,776 (Wood et al.) comprises a nozzle for mixing oxidizer with fuel. The mixed oxidant gas from an emitter and fuel droplets from a second channel converge in a dispersing chamber. The mixture is carried by air flow moving through an intake manifold passageway to a cylinder, where combustion occurs.
Our invention also includes, in combination in the preferred embodiment, a recently developed racing fuel. It comprises in combination, a necessary component of our invention in the preferred embodiment thereof.
Our invention also includes a methodology for drilling the orifices into the nozzle chamber which are contiguous with the channels therein. Use of a drill with a computer programmed machine results in wider orifices and straighter, less irregular and more precisely located channels. This methodology results in less turbulence within the nozzle. The computer program and associated machine are well known in the art. | {
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(a) Field of the Invention
The present invention relates to a portable detector device for detecting partial electrical discharge in live voltage distribution cables and/or equipment located above or below ground (such as in manholes).
(b) Description of Prior Art
Electrical utilities share a keen interest in technological advances that promise better reliability and greater safety of their power transmission and distribution systems. They invest heavily in the evaluation of system components, control and communication equipment, installation and non-destructive measurement techniques in an aim to minimize power outages and the duration of any unavoidable system down time. Service continuity is often difficult to maintain due to existing conditions of cables and joints without jeopardizing the safety of operating personnel required to maintain and repair the distribution lines and equipment.
Electrical utilities are always striving to improve the safety of their personnel working in manholes or above ground on the utilities' extensive distribution network. Therefore, there is a need to provide a simple portable tool for checking the state of cables and joints in manholes or above ground, and that would ensure greater safety to the user and which could evaluate partial discharge levels in cables and joints in normal system operating conditions. Partial discharge measurement represents the most informative non-destructive test of the quality of extruded solid dielectrics, since the presence of such discharges at operating voltage, gives a positive indication of serious problems in the near future.
However, partial discharges are very difficult to measure owing to the need to eliminate extrenuous electromagnetic interference while maintaining the supply of high cable charging current. Balanced bridge circuity using low frequency (0.001 hz) test source is one solution, although it is not as easy to use as a general go or no-go test. There is, therefore, a need to provide a detector device capable of detecting non-electrical signals, in decibals, microvolts, etc. that could be related to partial discharges measured by standard techniques (in microcoulombs). | {
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1. Field of the Invention
This invention relates to sealed bearing rotary cone rock bits.
More particularly, this invention relates to precision roller bearings for seal bearing rotary cone rock bits.
2. Description of the Prior Art
Roller bearings for rotary cone rock bits have been in the public domain for many years. Roller bearing "air" bits are typically used in open pit mines where a multiplicity of shallow holes are formed in the earth formations. These types of roller bearing rotary cone bits usually are non-sealed bits that rely on a gaseous fluid to lubricate the bearings and to flush the bearings of debris during use of the bit in a borehole. These types of mining bits utilize cylindrical roller bearings that are loosely confined (large bearing clearances) by bearing races formed between a journal and a rotary cutter cone. These open-type bearings encourage the flushing of detritus from the bearing cage by the gaseous fluid pumped under pressure through a connecting drill string.
Prior art U.S. Pat. Nos. 2,030,442, 3,990,525, 4,255,000, 44,359,113 and 4,386,668 represent rock bits that operate under the foregoing parameters.
Sealed bearing rotary cone rock bits that incorporate cylindrical type roller bearings are typically run in a deep well borehole with drilling fluid or "mud" to move the debris from the borehole bottom to the rig floor.
The following U.S. Pat. Nos. 4,249,781, 4,256,193, 4,263,976 and 4,428,687 teach sealed lubricated roller bearings for rotary cone rock bits.
Still another type of rotary cone rock bit utilizes conical bearings oriented between journals and rotary cones. The conical bearings take both radial and axial loads during operation of the bit in a borehole.
U.S. Pat. No. 4,136,748 teaches an open bearing rotary cone rock bit (air bit) with conical bearings that utilizes a gaseous fluid to lubricate and flush the bearings.
U.S. Pat. No. 4,367,904 teaches a sealed bearing rotary cone rock bit that uses conical bearings that are internally grease lubricated through a closed lube reservoir system.
The prior art does not teach a precision roller bearing having very close fits. The bearing package of the present invention includes highly refined surface finishes that complement extremely hard roller bearing elements fabricated from special bearing metals. A specific lubricant is utilized having lube viscosities that are unique to the bearing combination of the instant invention. | {
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This invention relates to an improvement in the active flight control of an air vehicle, and more particularly, but not by way of limitation, to a split span fin tail control arrangement whereby inner and outer spans of each fin are independently operable to provide yaw, roll, and pitch control for an air vehicle in flight.
The control of air vehicles in flight, such as manned air vehicles, is provided by control surfaces located in the tail area of the vehicle. These controlled surfaces include the horizontal tail area which includes a horizontally disposed elevator of which approximately 60% is fixed with remainder being movable about an horizontal axis. In steady flight the function of the horizontal elevator is to balance or trim the air vehicle to ensure the resultant of all the air forces on the vehicle pass through its center of gravity. The trim control provided by the horizontal elevator provides longitudinal or pitch control of the air vehicle.
The vertical tail portion includes vertical stabilizing and controlling surfaces that are provided by a fixed fin and a movable rudder. These surfaces perform the same function as the rudder in a boat. The fixed fin provides directional stability; i.e., it provides a means to "yaw" the air vehicle and change the direction of flight and it is used to trim the air vehicle for straight flight. The control surfaces of the horizontal and vertical tail surfaces cooperate to control the roll of the vehicle in flight.
The term "air vehicles" is also considered to include unmanned air vehicles with which the present invention may be employed to particular advantage. Unmanned air vehicles may be used for missions such as the delivery of a payload in which the mission requirements necessitate guidance of the vehicle in flight to a precise target. Unmanned air vehicles may also be used for such tasks as day/night reconnaissance, surveillance and target acquisition systems which use the unmanned air vehicles as sensor platforms. The propulsion for an unmanned air vehicle may be provided by a rocket motor, gas turbine engine, or by a reciprocating internal combustion engine. Such unmanned air vehicles may be vertically launched or be launched in flight from a manned air vehicle.
Generally speaking, the most common means to provide longitudinal and directional stability for an unmanned air vehicle included a minimum of three active control fins and often four such fins. As opposed to the horizontal and vertical tail control surfaces commonly used for manned air vehicles as described above, the active control surfaces of an unmanned air vehicle provides for controllable movement of the entire fin about an axis normal to the center line of the air vehicle. | {
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The present invention relates to a method for manufacturing a rigid, perforated cloth or fabric.
It is well known in the art to adapt woven fabrics as filter elements for filtering particulate matter from a liquid or gaseous fluid as that fluid passes across the woven fabric filter element. Such filter elements have been produced from woven metallic wire; however, filters so produced suffer the disadvantage that they cannot be used for the filtration of chemical compounds with which the metal of the wires is prone to react.
Woven fabric filter elements have also been made from monofilament of synthetic materials such as, for example, polyester. However, these filter elements suffer from shortcomings essentially inherent to the ability of the synthetic monofilaments to stretch, thus limiting their use to working pressures below the irreversible elastic deformation limit of the synthetic materials.
It has been proposed to manufacture filter fabrics from glass yarns, but such filters, because of the transverse fragility of the elementary glass filaments, show poor resistence to abrasion by the materials to be filtered and accordingly deteriorate rapidly.
In order to overcome these and other shortcomings, it has been proposed to coat the filter fabric material with a suitable thermoplastic polymer. However, this technique has not been entirely satisfactory because such technique is delicate to carry out, requires specific apparatus to coat the fabrics with an appropriate polymer and, finally, does not provide for satisfactory control in the way the individual yarns comprising the fabric network are bonded together, thereby producing deformation of the fabric network which adversely affects the filtering capacity of the woven fabric filter.
It has also been proposed to produce woven fabrics from yarns previously coated with a sleeve of plastic by weaving the coated yarns into a fabric network and thereafter heating the fabric by, for example, hot calendering, in order to bond the yarns to each other at their points of intersection. Such procedures are more specifically described in French Pat. Nos. 1,041,697 and 1,502,610. Unfortunately, this technique, which is satisfactory for the manufacture of fabrics for window blinds and curtains, requires special equipment, precise operation and considerable time in which to make the woven fabric. | {
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It is common practice to attach connectors between structural members of a building, such as between support walls and a buildings concrete foundation to reinforce these connections. In this instance, the connector is at least partially embedded in the concrete foundation. An example of such a connector is a strap tie holdown connector which is attached to an outer surface of the support wall.
The holdown is held in place prior to pouring the concrete foundations in which it is embedded. Thus, it is desirable that the positioning of the holdown be as accurate as possible. One way holdowns are held in place is to nail them directly to the form used when pouring the concrete foundation. However, this method is not capable of consistently and reliably setting a correct embedment depth of the holdown. | {
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Warheads with shaped-charge munitions, also known as hollow charge munition, are known to pierce armors and thereby destroy the protected object from within and, its contents. This capacity of a shaped-charge results from the fact that upon detonation there forms an energy-rich jet also known as “thorn” or “spike” which advances at very high speed of several thousands of meters per second and is thereby capable of piercing even relatively thick armor walls.
Several arrangements have become available in recent years to afford protection against the penetrating effect of an exploding shaped charge, wherein a structure holding at least one reactive armor element, wherein reactive armor element comprises an array of layers comprising one or more plate layers and at least one layer of explosive or any other energetic material (‘energetic material’—a material releasing energy during activation/excitement), tightly bearing against at least one of the plate layers. The plate layers are made, for example, of metal or a composite material.
A basic reactive armor element comprises two metal plates sandwiching between them the layer of energetic material. Such prior art reactive armor elements are based on the mass and energy consuming effects of moving plates and their functioning is conditional on the existence of an acute angle between the jet of an oncoming hollow charge threat and the armor itself.
In general, a reactive armor element is a multi-layer body in which each layer tightly bears against each contiguous layer, wherein the multi-layer body includes an outer cover plate, at least one layer of energetic material, at least one intermediary inert body juxtaposed to each of the at least one energetic material layer. Upon activation/excitement of the energetic material (e.g. upon striking by shaped-charge warhead) the jet energizes the armor, where a vast energy discharge occurs so that within microseconds the discharged gases accelerate the metal plates and displaces them away from one another thus disrupting/defeating the jet, thereby loosing its energy to penetrate the protected enclosure.
Whilst efficiency and survivability of the armor are important, the overall performance of an armor is determined by comparing its efficiency versus its survivability. One criteria of an armor, having significant importance, is the ratio of weight per area unit of the armor element. Another criterion of importance is sensitivity of the energetic material. Whilst sensitivity may be an advantage for improving efficiency of the armor, it may reduce survivability of the armor and it may be problematic as far as complying with various transportation requirements.
There are known four principal groups of intermediate materials for armors, disclosed hereinafter in order of their energetic catachrestic:
A. Explosive Reactive Armor (ERA)
Explosive Reactive Armor is the most effective technology to defeat hollow charges, kinetic projectiles, small arms, shrapnel etc. Advanced ERA concepts are considered leap-ahead technology against emerging anti-armor threats. The major challenges of applying ERA to ground combat vehicles are the use of an explosive material as an intermediate layer of the sandwich element, reducing survivability of the armor.
B. Self-Limiting Explosive Reactive Armor (SLERA)
Self-Limiting ERA provides reasonable performance, substantially better than NERA (see below), though less than ERA, with reduced effects on vehicle structures, as compared to ERA. The energetic material layer in SLERA has the potential of being classified as a passive material (NATO specification). SLERA can provide good multiple-hit capability in modular configuration. Thus, while the energetic material used in SLERA is not as effective as fully detonable explosives, this type of reactive armor may provide a more practical option than ERA owing to its survivability characteristics.
C. Non-Explosive Reactive Armor (NxRA)
Non-Explosive Reactive Armor provides a comparable efficiency to SLERA, comparable survivability to NERA (see below), and excellent multiple-hit capability against hollow charge warheads. NxRA's advantages over other reactive armor technologies are that it is totally passive and has substantially better efficiency than NERA. Energetic materials for NxRA are disclosed for example in DE 3132008C1 and in U.S. Pat. No. 4,881,448.
D. Non-Energetic Reactive Armor (NERA)
Non-Energetic Reactive Armor has limited efficiency against hollow charges. NERA's advantage is that it is totally passive and thus provides excellent survivability and maximal multiple-hit capability, comparable to NxRA.
It is an object of the present invention to provide a non-explosive energetic material suitable for NxRA which does not contain explosive material and fulfills its protective function (high efficiency and high survivability of the armor), whilst the non-explosive energetic material lowers the requirements of transportation and logistics according to various standards e.g. UN regulations as appearing in the Recommendations on the Transport of Dangerous Goods.
It is a further object of the present invention to provide an armor element fitted for such an energetic material and where the armor is of comparable efficiency to SLERA and of comparable survivability to NERA. | {
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This application is based on and claims priority from Japanese Patent Application Nos. HEI 3-252687 filed Jun. 26, 1991 and HEI 4-101383 filed Apr. 21, 1992, the disclosure of which is incorporated by reference herein.
The present invention relates to a scanning optical system such as a laser printer or a laser photoplotter and, more particularly, to a system having a monitoring unit that is capable of indirect detection of the position in which a laser beam spot is scanned over the image plane.
Some conventional models of scanning optical system that require high patterning or imaging precision are equipped with a monitoring optical unit for detecting the position in which a laser beam spot is scanned over the image plane. The conventional monitoring optical units are available in various types; in one type, part of the writing beam is isolated by a half mirror and used for monitoring purposes; in another type, the output light is divided into two beamlets by means of a polarizing beam splitter; and in still another type, the writing beam and the monitoring beam are allowed to fall on a polygonal mirror at different angles of incidence with respect to the sub-scanning direction, whereby the two light beams are spatially separated.
However, the respective types have their own problems. The optical unit using a half mirror is unable to produce a monitor signal, when patterning or imaging is not done. With the unit that uses a polarizing beam splitter, perfect isolation of polarized beams is impossible. In addition, since the polarizing performance is varied in accordance with the angle of incidence of the beam relative to the polarizing splitter, the quality to the written image would be adversely affected. The unit for achieving spatial isolation between the writing beam and the monitoring beam has the problem of curvature in the scanning lines of the monitoring beam. In addition, efficient isolation is difficult if a scanning lens of small F number is to be used. | {
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Traditionally, a network is controlled at each of the Open Systems Interconnection (OSI) layers. The OSI model is a logical structure for network operations standardized by the International Standards Organization (ISO). The OSI model organizes the communications process into seven different categories and places these categories into a layered sequence based upon their relationships to other processes. Layers seven through four deal with end-to-end communications between a message source and a message destination, while layers three through one deal with network access. The layers communicate with their peers in the network. For example, at layer 0, optics can be populated with specific wavelengths. In some automated systems, optics can be programmed with certain characteristics, such as wavelengths, filters, and optical switching capabilities at the optical layer. Typically, these are all controlled by an Element Management System (EMS), Network Management System (NMS), or Operations Support System (OSS). For example, at layer 1, the network is typically based on a Synchronous Optical Network/Synchronous Digital Hierarchy (SONET/SDH) standard, offering virtual Time Division Multiplexing (TDM) and data channels within the bit streams. The channels are built, switched, or dismantled at nodes. Again, this is typically controlled by the EMS. More recently, layer-specific resource control protocols, such as Resource Reservation Protocol (RSVP), have been defined to control the network (reference Generalized Multi-Protocol Label Switching (GMPLS)). For example, at layer 2, a common protocol is Ethernet. Ethernet networks can be provisioned as in Provider Backbone Transport (PBT) networks (http://www.ieee802.org/1/files/public/docs2005/ah-bottorff-pbt-for-iee-v41-0905.pdf or http://www.ietf.org/internet-drafts/draft-allan-pw-o-pbt-00.txt). However, Ethernet networks typically provision simply by using the broadcast mechanism that is inherent in Ethernet. Optimizations have been added to extend reach and efficiency, such as bridges and multi-link bonding, which has added to the complexity of the protocols used, without changing the basic principles. For example, at layer 3, the Internet Protocol (IP) layer, IP routing is used to interconnect nodes in a network. Typically, these nodes all run routing protocols, such as Routing Information Protocol (RIP), Open Shortest Path First (OSPF) protocol, etc. Modern networks often apply key mechanisms, such as Multi-Protocol Label Switching (MPLS), at this layer in order to enhance the scalability of, add features to, or increase the stability of the networks. For example, at layer 4, data transport reliability, service ports, and the like are addressed. For example, at layer 5, the session layer, SIP can be used to initiate sessions. A session is a communication of some form between two peer entities. A relevant example is the initiation of a voice call from a wireless (WiFi)-enabled Personal Digital Assistant (PDA). The WiFi-enabled PDA generates the voice call to another user in a form such as “INVITE [email protected]” using SIP. The SIP agents track “name” and are aware of many items, such as, but not limited to, the location of “name” (e.g. “name” is now in “city”), the presence/availability of “name” (e.g. “name” can only be contacted by “family” at this time), and the media of “name” (e.g. “name” has set up the network to forward voice calls to a home voicemail at this time).
Current efforts to define protocols for optical networking have focused on layer-specific controls. Disadvantageously, layer-specific controls require accessing each layer to set up resources and/or services across the network. For example, for layer 0, protocol definition has focused on the specification of the wavelength to be used for a connection, the level of optical impairments that are allowed in the connection, and the source and destination within an optical network. Additionally, for layer 1, protocol definition has focused on the specification of the timeslot to be used for a connection within a TDM signal, the type of links to be used in the sense of any automated protection functionality associated with the links, etc. This work has been defined in the Internet Engineering Task Force (IETF) standards, such as Request for Comments (RFC) 3471, the GMPLS signaling functional description; RFC 3473, the GMPLS signaling extensions to RSVP; and RFC 3946, the GMPLS extensions for SONET/SDH control.
What has not been fully explored, however, is the area of technology-independent control that is required to offer services over a particular layer network. This is termed “call control” in the related standards (especially Automatically Switched Optical Network (ASON) or International Telecommunications Union (ITU-T) Recommendation G.8080) and is currently embodied in protocols only as a common identifier that links together signaling for multiple connections, or as a connection-independent control plane flow for purposes such as pre-connection compatibility verification. The former is described in ITU-T Recommendation G.7713.2, the specification for Distributed Call/Connection Management Using GMPLS RSVP-TE, while the latter is described in IETF draft “draft-ietf-ccamp-gmpls-rsvp-te-call-00.txt,” a work in progress. | {
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1. The Field of the Invention
The present invention relates in general to the improvement of the fracture strength or tensile strength of end sections of glass tubes against mechanical or thermal loads, as they typically occur in the course of further processing at the respective end section, and relates in particular to a process for the production of glass tubes with reduced stress in or at at least one tube end, preferably in or at both tube ends, wherein according to a further aspect of the present invention the intention is to create a predetermined stress profile in at least one tube end section.
2. The Description of the Related Art
After being cut or cut to length from a glass tube stream, industrially produced glass tubes have a specific stress curve, such as is illustrated by way of example in FIG. 1a, in the region of the tube ends and after heating of the tube ends. This stress curve is the result of the cutting process used and is induced by subsequent fusing of the tube ends. The tube end described here lies by way of example in the region at a distance between 0 and 50 mm to the respective tube end.
If such a tube end is used directly and without appropriate post-treatment in a glass-to-metal joint, the result due to the steep gradient between tensile stress and compressive stress at the tube end after thermal processing, e.g. on heating with glass solder, is splitting off during the cooling process due to stress induction (also referred to as “ring fracturing” of the tube end.) This leads to the complete destruction of a glass-to-metal joint such as is illustrated by way of example in FIG. 3b and will be described in greater detail below.
In order nevertheless to use glass tubes for glass-to-metal joints the entire glass tube is subjected according to the prior art to what is referred to as precision cooling. For this purpose the entire glass tube passes, after being severed from the glass tube line and cooling to ambient temperature, into a separate oven in which the entire glass tube is subjected to a controlled heat treatment, i.e. a predetermined heat treatment with precisely defined heating and cooling curve. FIG. 1b illustrates the stress curve at a tube end of such a glass tube that is conventionally subjected to precision cooling. In the region of the arrows, as indicated by reference letters A and B, there is a significant reduction in the compressive stress (in region A) and tensile stress (in region B) as a result of the precision cooling.
There are cooling curves adapted to each type of glass that are supposed to bring about a reduction in the stress. The general doctrine says that for the stress relief of glass a time period of at least 15 min is required between the annealing point at a viscosity η=1013.5 Pa s and the strain point at a viscosity η=1012 Pa s to reduce the stress to such an extent that it is possible to process the glass safely (without breakage). Subsequently, the temperature of the glass item must be decreased at a rate of 2° C./min from the annealing point to the strain point. Such a precision cooling of glass tubes is therefore very time-consuming because several hours are usually needed for heating up and cooling down.
Such a precision cooling is also very costly and usually consumes a lot of energy. An annealing lehr is normally used for cooling glass or for controlling the stresses from the center of the tube towards the end of the tube. For this purpose a glass item or the glass tube is placed into the annealing lehr, passes through a predetermined cooling curve and is then removed from the lehr and packaged.
In addition, the atmosphere in conventional ovens used for precision cooling is relatively dirty with the result that the glass tubes have to be laboriously cleaned after the precision cooling, for instance if they have to be coated for a subsequent use.
One way out in order to eliminate these problems is to cut off and discard the respective tube end sections after cooling down completely to ambient temperature. However, this reduces efficiency and increases the costs of glass tube production.
U.S. Pat. No. 2,166,871 A describes a process in which a glass gob is continuously severed, in a heat-softened state, from a glass tube line (glass drawing line) and subsequently formed. Viscosities or temperatures around the working point at a viscosity η=104 Pa s are required for this purpose. The glass gob thus produced is subsequently subjected to a heat treatment that is not described in greater detail.
GB 826,270A discloses a process for severing glass tubes that is primarily used for large glass tube diameters. The glass tube, after local heating using burners, is heated until melted off by applying a very high electric voltage. Due to this very rapid local overheating, the severed glass tube must be heated up immediately after being severed to prevent stress cracks (“runners”) induced by the high temperature difference. For this purpose the still heated glass tube is placed on a transport means which moves the glass tube past heating devices provided laterally. However, in this case there is no passage through a heating region with a predetermined temperature profile, which extends in the longitudinal direction of the glass tube and in which the temperature of the glass tube is selectively and locally increased depending on a distance to the respective tube end. | {
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This disclosure relates to limb supports generally, to chair armrests specifically, and to ergonomic arm pads in particular. Horizontally movable arm pads are more preferable than stationary ones in part because they are adjustable to fit a user's desired supporting position. A horizontally movable armrest may be attached to an arm support through one or more slot tracks that permit the arm pad to move laterally. When independently actuable fasteners are inserted through the slot tracks to attach the arm pad to the arm support, the movement of the arm pad is bound by the edges of the slot tracks. In other words, the slot tracks guide the movement of the arm pad. As a user attempts to position the arm pad, such configurations can lead to misfunctioning, abrupt movement, or even an unintentionally locked arm pad because the fasteners are not cooperating and the fasteners knock along the edges of the slot tracks. | {
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A compact vehicle is disclosed for instance in US2006219452. In this compact vehicle, an engine unit comprising a V-belt type automatic transmission is mounted below the seat, and an electric power steering system is installed.
Furthermore, compact vehicles include vehicles equipped with an electronic fuel injection system.
There is a demand in the market for vehicles that have a compact body while having more complete accessories of various types. However, when an electric power steering unit is provided, a relatively large electric motor and gear mechanism become necessary, and when an electronic fuel injection system is provided, a relatively large fuel pump to supply high pressure fuel to the fuel injection valve becomes necessary, so the problem of the width dimension and height dimension of the vehicle body becoming larger depending on how these components are laid out becomes a concern. | {
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I. Field
The present invention relates generally to delivery of information over a communication system, and more specifically, to partitioning of information units to match a physical layer packet of a constant bit rate communication link.
II. Background
Demand for the delivery of multimedia data over various communication networks is increasing. For example, consumers desire the delivery of streaming video over various communication channels, such as the Internet, wire-line and radio networks. Multimedia data can be different formats and data rates, and the various communication networks use different mechanisms for transmission of real time data over their respective communication channels.
One type of communication network that has become commonplace is mobile radio networks for wireless communications. Wireless communication systems have many applications including, for example, cellular telephones, paging, wireless local loops, personal digital assistants (PDAs), Internet telephony, and satellite communication systems. A particularly important application is cellular telephone systems for mobile subscribers. As used herein, the term “cellular” system encompasses both cellular and personal communications services (PCS) frequencies. Various over-the-air interfaces have been developed for such cellular telephone systems including frequency division multiple access (FDMA), time division multiple access (TDMA), and code division multiple access (CDMA).
Different domestic and international standards have been established to support the various air interfaces including, for example, Advanced Mobile Phone Service (AMPS), Global System for Mobile (GSM), General Packet Radio Service (GPRS), Enhanced Data GSM Environment (EDGE), Interim Standard 95 (IS-95) and its derivatives, IS-95A, IS-95B, ANSI J-STD-008 (often referred to collectively herein as IS-95), and emerging high-data-rate systems such as cdma 2000, Universal Mobile Telecommunications Service (UMTS), and wideband CDMA, (WCDMA). These standards are promulgated by the Telecommunication Industry Association (TIA), 3rd Generation partnership Project (3GPP), European Telecommunication Standards Institute (ETSI), and other well-known standards bodies.
Users, or customers, of mobile radio networks, such as cellular telephone networks, would like to receive streaming media such as video, multimedia, and Internet Protocol (IP) over a wireless communication link. For example, customers desire to be able to receive streaming video, such as a teleconference or television broadcasts, on their cell phone or other portable wireless communication device. Other examples of the type of data that customers desire to receive with their wireless communication device include multimedia multicast/broadcast and Internet access.
There are different types of sources of multimedia data and different types of communication channels on which it is desired to transmit the streaming data. For example, a multimedia data source can produce data at a constant bit rate (CBR) or a variable bit rate (VBR). In addition, the communication channel can transmit data at a CBR or a VBR. Table 1 below list various combinations of data sources and communication channels.
TABLE 1SourceChannelExampleCBRCBRmu-law, or A-law on PSTNVBRVBRMPEG-4 over wire-line IP network, cdma2000variable rate vocoders such as 13K vocoder, EVRCand SMV over fundamental channel (FCH)CBRVBRAMR streaming on cdma2000 FCHVBRCBRCompressed video over circuit switched Wirelessnetworks (3G-324M)
Communication channels typically transmit data in chunks, which we refer to as physical layer packets or physical layer frames. The data generated by the multimedia source may be a continuous stream of bytes, such as a voice signal encoded using the mu-law or A-law. More frequently, the data generated by the multimedia source consists in groups of bytes, called data packets. For example, an MPEG-4 video encoder compresses visual information as a sequence of information units, which we refer herein as video frames. Visual information is typically encoded at a constant video frame rate by the encoder, of typically 25 or 30 Hz, and must be rendered at the same rate by the decoder. The video frame period is the time between two video frames and can be computed as the inverse of the video frame rate, for example the video frame period of 40 ms corresponds to a video frame rate of 25 Hz. Each video frame is encoded into a variable number of data packets, and all the data packets are transmitted to the decoder. If a portion of a data packet is lost, that packet becomes unusable by the decoder. On the other hand, the decoder may reconstitute the video frame even if some of the data packets are lost, but at the cost of some quality degradation in the resulting video sequence. Each data packet therefore contains part of the description of the video frame, and the number packets are therefore variable from one video frame to another.
In the case when a source produces data at a constant bit rate and a communication channel transmits data at a constant rate, the communication system resources are efficiently utilized, assuming that the communication channel data rate is at least as fast as the source data rate, or if the two data rates are otherwise matched. In other words, if the constant data rate of the source is the same as the constant data rate of the channel, then the resources of the channel can be fully utilized, and the source data can be transmitted with no delay. Likewise, if the source produces data at a variable rate and the channel transmits at a variable rate, then as long as the channel data rate can support the source data rate, then the two data rates can be matched and, again, the resources of the channel are fully utilized and all of the source data can be transmitted with no delay.
If the source produces data at a constant data rate and the channel is a variable data rate channel, then the channel resources may not be as efficiently utilized as possible. For example, in this mismatched case the statistical multiplexing gain (SMG) is less than that compared with a CBR source on a matched CBR channel. Statistical multiplexing gain results when the same communication channel can be used, or multiplexed, between multiple users. For example, when a communication channel is used to transmit voice, the speaker does not usually talk continuously. That is, there will be a “talk” spurt from the speaker followed by silence (listening). If the ratio of time for the “talk” spurt to the silence was, for example 1:1, then on average the same communication channel could be multiplexed and could support two users. But in the case where the data source has a constant data rate and is delivered over a variable rate channel, there is no SMG because there is no time when the communication channel can be used by another user. That is, there is no break during “silence” for a CBR source.
The last case noted in Table 1 above, is the situation when the source of multimedia data is a variable bit rate stream, such as a multimedia data stream like video, and it is transmitted over a communication channel that has a constant bit rate, such as a wireless radio channel with a constant bit rate assignment. In this case, delay is typically introduced between the source and the communication channel, creating “spurts” of data so that the communication channel can be efficiently utilized. In other words, the variable rate data stream is stored in a buffer and delayed long enough so that the output of the buffer can be emptied at a constant data rate, to match the channel fixed data rate. The buffer needs to store, or delay, enough data so that it is able to maintain a constant output without “emptying” the buffer so the CBR communication channel is fully utilized sand the communication channel's resources are not wasted.
The encoder periodically generates video frames according to the video frame period. Video frames consist of data packets, and the total amount of data in a video frame is variable. The video decoder must render the video frames at the same video frame rate used by the encoder in order to ensure an acceptable result for the viewer. The transmission of video frames, which have a variable amount of data, at a constant video frame rate and over a constant rate communication channel can result in inefficiency. For example, if the total amount of data in a video frame is too large to be transmitted within the video frame period at the bit rate of the channel, then the decoder may not receive the entire frame in time to render it according to the video frame rate. In practice, a traffic shaping buffer is used to smooth such large variations for delivery over a constant rate channel. This introduces a delay in rendering the video, if a constant video frame rate is to be maintained by the decoder.
Another problem is that if data from multiple video frames is contained in a single physical layer packet, then the loss of a single physical layer packet results in degradation of multiple video frames. Even for the situations when the data packets are close to the physical layer packet sizes, the loss of one physical layer packet can result in the degradation of multiple video frames.
There is therefore a need in the art for techniques and apparatus that can improve the transmission of variable data rate multimedia data over a wireless communication channel. | {
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1. Field of the Invention
This invention relates generally to radio frequency power amplifiers and, more particularly, the invention relates to methods of managing the signal to noise floor ratio as the operational bandwidth of a digital linearized predistortion amplifier is expanded.
2. Description of the Related Art
Radio frequency power amplifiers are widely used to transmit signals in communications systems. Typically a signal to be transmitted is concentrated around a particular carrier frequency occupying a defined channel. Information is sent in the form of modulation of amplitude, phase, and/or frequency such that the information is represented by energy spread over a band of frequencies around the carrier frequency. In many schemes the carrier itself is not sent since it is not essential to the communication of the information.
When a signal that contains amplitude variations is amplified, it will suffer distortion if the amplifier does not exhibit a linear amplitude and phase transfer characteristic. This means that the output is not linearly proportional to the input. The signal will also suffer distortion if the phase shift, which the amplifier introduces, is not linear over the range of frequencies present in the signal or if the phase shift caused by the amplifier varies with the amplitude of the input signal. The distortion introduced typically includes intermodulation of the components of the input signal. The products of the intermodulation appear within the bandwidth of the signal causing undesirable interference. The products of the intermodulation also extend outside the bandwidth originally occupied by the signal. This can cause interference in adjacent channels and violate transmitter licensing and regulatory spectral emission requirements. Although filtering can be used to remove the unwanted out of band distortion, this is not always practical, especially if the amplifier is required to operate on several different frequencies.
Distortion products that occur at multiples of the carrier frequency can also be produced in a non-linear amplifier, but are relatively easy to remove by filtering. Intermodulation is also a problem when multiple signals are amplified in the same amplifier even if individually they do not have amplitude variations. This is because the combination of the multiple signals produces amplitude variations as the various components beat with each other by adding and subtracting as their phase relationships change.
Amplifiers can introduce some distortion even if they are well designed. Perfect linearity over a wide range of amplitude is difficult to realize in practice. In addition, as any amplifier nears its maximum output power capacity, the output no longer increases as the input increases. At this point the amplifier is not regarded as linear. A typical amplifier becomes significantly non-linear at a small fraction of its maximum output capacity. This means that in order to maintain linearity, the amplifier is often operated at an input and output amplitude which is low enough that the signals to be amplified are in a part of its transfer characteristic that is substantially linear. This is a method of operation, described as xe2x80x9cbacked off,xe2x80x9d in which the amplifier has a low supplied power to transmitted power conversion efficiency. A xe2x80x9cClass Axe2x80x9d amplifier operating in this mode may be linear enough for transmitting a signal cleanly but might typically be only 1% efficient. This wastes power and means that the amplifier has to be large and relatively expensive. In addition, the wasted power is dissipated as heat, which generally must be removed by cooling means.
Communication schemes using signals which have constant amplitude with frequency and phase modulation can use highly non-linear amplifiers. These types of signals are unaffected by the distortion and the amplifiers can be smaller, cooler, more power efficient and less expensive. Modulation of this type is used in conventional radio paging systems, which use CPFSK modulation.
Many of the newer, bandwidth efficient modulation schemes have both amplitude and phase variations. There is also frequently a desire to be able to transmit multiple signals on different channels through a single amplifier. This reduces the number of separate amplifiers required and avoids the need for large and costly high level output signal combining filters, which have undesirable power losses.
There is a need for linear amplifiers which are compact, power efficient and inexpensive. Linearized amplifiers can be made by correcting for the non-linearities of amplifiers using methods such as Cartesian feedback, predistortion, and feedforward correction.
Cartesian feedback is a method in which a monitoring system looks at the output of the amplifier and attempts to alter the input of the amplifier so that it produces the intended output. This is accomplished using a direct feedback loop. The delay in the feedback path can cause the input signal to be modified too slowly to provide effective compensation, especially with signals at higher bandwidths.
The traditional predistortion method attempts to correct for the non-linear transfer characteristic of an amplifier by forming an inverse model of its transfer characteristic. This characteristic is applied to the low level signal at the input of the amplifier in a nonlinear memory-less function to predistort the signal such that the amplified signal appears substantially undistorted. This method is capable of excellent results over a relatively small bandwidth. The non-linear memory-less function is updated to account for variations in the amplifier transfer characteristic and this is done by monitoring the output and periodically updating the correction parameters. The non-linear coefficients of the memory-less function may be changed as often as every sample using the values stored in memory.
Feedforward is a method that derives a signal which represents the inverse of the distortions produced by the amplifier. This can be done by comparing the amplifier input and output to extract a distortion signal. A small linear amplifier is used to amplify the distortion signal. The amplified distortion signal is then subtracted from the main amplifier output. This method gives good results over a relatively wide bandwidth. However, balancing the amplitude and delay of the distortion signal so that it cancels the main amplifier errors exactly is difficult to implement.
Both traditional feedforward and predistortion are widely used in commercial products which can amplify multiple signals and operate over a wide range of amplitudes. Both methods are quite complex and the power efficiencies are still not excellent. Feedforward amplifiers are typically only 5% efficient. The complicated processing requirements add to the cost and the power used and significant cooling capacity is still required to remove waste heat. Predistortion is capable of excellent results, but only over a relatively small bandwidth.
The present invention provides methods of managing the signal to noise floor ratio exhibited in individual subbands as the operational bandwidth of a digital linearized predistortion amplifier is expanded.
In one aspect of the invention, a digital input signal is separated into subbands of lower bandwidth. The digital input signal is preferably a wideband signal that has one or both of the following characteristics: (a) the signal exists at one or more frequencies within an operating bandwidth within a time interval that is the reciprocal of the total information bandwidth; (b) the signal consists of multiple information bearing subcarriers and has a spectral occupancy that exceeds 0.1% of the RF carrier frequency. Each of the digital subband signals, which has a lower power than the digital input signal, is separately converted to an analog subband signal using a separate DAC. The separately converted analog subband signals are combined to form an analog input signal. By separating the digital signal into subbands, separate DACs can be used and the power of the signal to be handled by any one DAC is reduced.
In another aspect of the invention, a digital correction signal is created by taking the difference between a digital predistortion signal and the digital input signal. The digital predistortion signal, which is a signal that is typically passed through a Digital to Analog Converter (DAC) and supplied to a non-linear amplifier, can be created using presently available techniques. In accordance with the invention, however, the digital input signal is removed from the digital predistortion signal to leave only the digital correction signal, which has a much lower power than the digital predistortion signal. The digital correction signal and the digital input signal (or its subbands) are separately converted to analog signals using separate DACs. The converted analog signals are combined by analog summation to form an analog predistorted signal. The analog predistorted signal is passed on to a non-linear amplifier.
The aforementioned aspects of the invention result in the separation of a digital signal into separate signals of lower power. In the prior art, a single DAC has been used to convert a combined signal of much higher power. In accordance with the present invention, however, multiple DACs are employed and each DAC converts a digital signal of a lower power. As a result, the available levels of quantization of each DAC are applied to a lower power signal and the lower power per quantum ratio provides a better signal to noise ratio. Accordingly, substantially the entire dynamic range of each DAC can be used to convert a signal to analog form.
In another aspect of the invention, each analog signal is passed through a separate narrow band reconstruction filter before the analog signals are combined. Each reconstruction filter can be configured specifically for a narrow frequency range. By passing each converted signal through a separate narrow reconstruction filter, a significantly higher signal to wideband noise ratio for the composite signal can be achieved. The use of separate reconstruction filters, however, may introduce relative gain, phase, and delay inconsistencies between the separate signals. These relative inconsistencies are caused by the analog nature of the reconstruction filters, which are preferably configured to handle specific narrow frequency bands.
In order to correct the relative inconsistencies between the separate signals, a digital correction filter is introduced in-line along each subband signal path before the DAC. The correction filters are driven by an Adaptive Control Processing and Compensation Estimator (ACPCE) block, which adaptively generates compensation parameters for the filters based on observations of the digital input signal and the output of the amplifier. | {
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1. Field of the Invention
The present invention relates to Mobile IP network technology. More particularly, the present invention relates to enabling a mobile network device to select a foreign agent.
2. Description of the Related Art
Mobile IP is a protocol that allows laptop computers or other mobile computer units (referred to as “Mobile Nodes” herein) to roam between various sub-networks at various locations—while maintaining Internet and/or WAN connectivity. Without Mobile IP or related protocol, a Mobile Node would be unable to stay connected while roaming through various sub-networks. This is because the IP address required for any node to communicate over the Internet is location specific.
Each IP address has a field that specifies the particular sub-network on which the node resides. If a user desires to take a computer that is normally attached to one node and roam with it so that it passes through different sub-networks, it cannot use its home base IP address. As a result, a business person traveling across the country cannot merely roam with his or her computer across geographically disparate network segments or wireless nodes while remaining connected over the Internet. This is not an acceptable state of affairs in the age of portable computational devices.
To address this problem, the Mobile IP protocol has been developed and implemented. An implementation of Mobile IP is described in RFC 2002 of the Network Working Group, C. Perkins, Ed., October 1996. Mobile IP is also described in the text “Mobile IP Unplugged” by J. Solomon, Prentice Hall. Both of these references are incorporated herein by reference in their entireties and for all purposes.
The Mobile IP process and environment are illustrated in FIG. 1. As used herein, a “mobile network device” will mean any mobile computing or telecommunication device that can communicate over the Internet (or a similar network), including but not limited to a mobile network device such as a router, a mobile personal computer, a mobile telephone, a mobile personal digital assistant and other mobile nodes. Some such devices may need to be used in connection with, e.g., a mobile access router running mobile IP. The descriptions herein regarding the movement of mobile nodes from home agent to foreign agents, etc., shall apply generally to the movement of mobile network devices unless otherwise specified.
As shown in FIG. 1, a Mobile IP environment 2 includes the Internet (or a WAN) 4 over which a Mobile Node 6 can communicate remotely via mediation by a Home Agent 8 and a Foreign Agent 10. Typically, the Home Agent and Foreign Agent are routers or other network connection devices performing appropriate Mobile IP functions as implemented by software, hardware, and/or firmware. A particular Mobile Node (e.g., a laptop computer, a mobile router, etc.) plugged into its home network segment connects with the Internet through its designated Home Agent. When the Mobile Node roams, it communicates via the Internet through an available Foreign Agent. Presumably, there are many Foreign Agents available at geographically disparate locations to allow widespread Internet connection via the Mobile IP protocol. Note that it is also possible for the Mobile Node to register directly with its Home Agent.
As shown in FIG. 1, Mobile Node 6 normally resides on (or is “based at”) a network segment 12 that allows its network entities to communicate over the Internet 4 through Home Agent 8 (an appropriately configured router denoted R2). Note that Home Agent 8 need not directly connect to the Internet. For example, as shown in FIG. 1, it may be connected through another network device (a router R1 in this case). Router R1 may, in turn, connect one or more other routers (e.g., a router R3) with the Internet.
Mobile Node 6 may be removed from its home base network segment 12 and may roam to a remote network segment 14. Network segment 14 may include various other nodes such as a PC 16. The nodes on network segment 14 communicate with the Internet through a router which doubles as Foreign Agent 10. Mobile Node 6 may identify Foreign Agent 10 through various transmissions made by Foreign Agent 10, including solicitations and advertisements, which form part of the Mobile IP protocol.
When Mobile Node 6 engages with network segment 14, Foreign Agent 10 relays a registration request to Home Agent 8 (as indicated by the dotted line “Registration”). The Home and Foreign Agents may then negotiate the conditions of the Mobile Node's attachment to Foreign Agent 10. For example, the attachment may be limited to a period of time, such as two hours. When the negotiation is successfully completed, Home Agent 8 typically updates an internal “mobility binding table” which specifies the care of address (e.g., a collocated care of address or the Foreign Agent's IP address) in association with the identity of Mobile Node 6. Further, the Foreign Agent 10 normally updates an internal “visitor table” which specifies the Mobile Node address, Home Agent address, etc. In effect, the Mobile Node's home base IP address (associated with segment 12) has been shifted to the Foreign Agent's IP address (associated with segment 14).
If Mobile Node 6 wishes to send a message to a corresponding node 18 from its new location, an output message from the Mobile Node is then packetized and forwarded through Foreign Agent 10 over the Internet 4 and to corresponding node 18 (as indicated by the dotted line “packet from MN”) according to a standard Internet protocol. If corresponding node 18 wishes to send a message to Mobile Node—whether in reply to a message from the Mobile Node or for any other reason—it addresses that message to the IP address of Mobile Node 6 on sub-network 12. The packets of that message are then forwarded over the Internet 4 and to router R1 and ultimately to Home Agent 8, as indicated by the dotted line (“packet to MN(1)”).
From its mobility binding table, Home Agent 8 recognizes that Mobile Node 6 is no longer attached to network segment 12. It then encapsulates the packets from corresponding node 18 (which are addressed to Mobile Node 6 on network segment 12) according to a Mobile IP protocol and forwards these encapsulated packets to a “care of” address for Mobile Node 6 as shown by the dotted line (“packet to MN(2)”). The care-of address may be, for example, the IP address of Foreign Agent 10. Foreign Agent 10 then strips the encapsulation and forwards the message to Mobile Node 6 on sub-network 14. The packet forwarding mechanism implemented by the Home and Foreign Agents is often referred to as “tunneling.”
In addition to providing connectivity to a mobile node, it may be desirable to provide for the mobility of one or more networks moving together, such as on an airplane or a ship. RFC 2002 section 4.5 discusses the possibility of implementing mobile routers.
If Mobile Node 6 (or a mobile router) continues to move, it will receive advertisements from other foreign agents. In general, if Mobile Node 6 receives an advertisement from a new foreign agent, Mobile Node 6 will “tear down” its tunnel connection with Foreign Agent 10 and establish a new connection with the new foreign agent.
However, the new foreign agent may not be the optimal foreign agent with which to establish a connection. For example, Mobile Node 6 may only receive advertisements from the new foreign agent for a brief period of time, as Mobile Node 6 travels in and out of the range of advertisements from the new foreign agent. This situation may be further complicated if Mobile Node 6 travels in and out of the range of advertisements from multiple foreign agents, or simply remains within overlapping ranges of multiple foreign agents. Under such circumstances, Mobile Node 6 would continue to tear down the established tunnel and create a new tunnel to the foreign agent from which Mobile Node 6 most recently received an advertisement. The process of tearing down and re-establishing a tunnel may take several seconds. Conventional mobile nodes and mobile routers do not have the ability to determine the optimal foreign agent with which to establish and maintain a connection under such circumstances. | {
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Neurologic and neuropsychiatric disorders such as depression, anxiety, amyotrophic lateral sclerosis, and central nervous system injuries, to name a few, afflict millions of people every year resulting in a multitude of symptoms including weight change, decreased energy, headaches, digestive problems, chronic pain, paralysis, and in certain instances, death.
One class of growth factors proposed as a treatment for neurologic and neuropsychiatric disorders are neurotrophins, which include brain-derived neurotrophic factor (BDNF). BDNF is believed to have neurotrophic action on various neuronal populations including sensory neurons, motor neurons, dopaminergic neurons of the substantia nigra, and cholinergic neurons of the basal forebrain, which are involved in several neurologic and neuropsychiatric disorders. Preclinical evidence indicates that BDNF might be useful as a therapeutic agent for various neurologic and neuropsychiatric disorders; however, the in vivo instability of such a peptide therapy limits its usefulness.
Neurotrophins are also indicated in metabolic disorders. Mutations in the tyrosine kinase receptor trkB or in one of its natural ligands, e.g., BDNF or neurotrophin-4 (NT4), are known to lead to severe hyperphagia and obesity in rodents and humans. Administration of trkB ligands such as BDNF or NT4 have been shown to suppress appetite and body weight in a dose-dependent manner in several murine models of obesity. Accumulating evidence indicates that TrkB signaling directly modulates appetite, metabolism, and taste preference. TrkB agonists thus emerge as potential therapeutics for metabolic disorders. | {
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The present invention relates generally to lithography and more particularly relates to a system and method for measuring films associated with lithography processes or other type semiconductor fabrication processes.
In the semiconductor industry there is a continuing trend toward higher device densities. To achieve these high densities there has been, and continues to be, efforts toward scaling down the device dimensions on semiconductor wafers. In order to accomplish such a high device packing density, smaller features sizes are required. This may include the width and spacing of interconnecting lines and the surface geometry such as the comers and edges of various features.
The requirement of small features with close spacing between adjacent features requires high resolution photolithographic processes. In general, lithography refers to processes for pattern transfer between various media. It is a technique used for integrated circuit fabrication in which, for example, a silicon wafer is coated uniformly with a radiation-sensitive film (e.g., a photoresist), and an exposing source (such as ultraviolet light, x-rays, or an electron beam) illuminates selected areas of the film surface through an intervening master template (e.g., a mask or reticle) to generate a particular pattern. The exposed pattern on the photoresist film is then developed with a solvent called a developer which makes the exposed pattern either soluble or insoluble depending on the type of photoresist (i e., positive or negative resist). The soluble portions of the resist are then removed, thus leaving a photoresist mask corresponding to the desired pattern on the silicon wafer for further processing.
As process designers continue to shrink the size of the features which make up various semiconductor components, various process parameters must be tightly controlled. For example, in order to provide small, repeatable feature sizes, the thickness of various films such as photoresist layers and anti-reflective coatings (ARCs) must be small and uniform about the surface of the wafer. Consequently, process designers regularly measure the thickness of such films.
Film thicknesses typically are determined using characterization equations provided by the tool manufacturers which use various film material constants such as absorption coefficients and optical constants such as the index of refraction. Using such equations, process developers can implement various tests and take various parametric measurements, insert the measured data into the equations, and calculate an approximate film thickness. Although such thickness determination techniques are modestly accurate, the characterization equations require that the various film material constants which characterize the film be known. For newly developed materials such as next generation photoresists and ARC materials, such advanced characterization data is not easily available, thus making the determination of such film thicknesses difficult.
The present invention relates to a system and method of measuring accurately a film thickness without the use of film material characterization data.
According to one aspect of the present invention, the system and method of measuring a film thickness includes identifying a location of a defect, for example, a crystalline defect, in an underlying material such as a semiconductor substrate. Using the defect location information, the depth or height of the defect is measured using, for example, a topography evaluation tool. After the film to be measured is formed over the underlying material, the defect, which is reproduced in the overlying film, is again measured to identify the depth or height associated therewith. Using the measured pre-film and post-film defect depth data, the film thickness is determined. The present invention avoids the need to have characterization data associated with the film to be measured and thereby facilitates process development using new and/or advanced film materials.
According to another aspect of the present invention, a method of determining a film thickness includes identifying a location of one or more defects such as pits or crystal-originated particle defects in a material such as a semiconductor wafer. Once the defect location(s) is identified, the location data is used to measure the depth or height of the defect(s). Subsequently, the film to be measured is formed over the material and, because the film generally is conformal, the defect(s) is reproduced therein. Again, using the defect location data, the depth or height of the defect(s) are measured. The defect depth/height data (both prior to film formation and after film formation) is then utilized to calculate the film thickness without the need of characterization data related to the film material. In addition, if multiple defects exist, the multiple data points may be utilized to determine an average film thickness along with other statistical data.
According to another aspect of the present invention, a system for determining a film thickness is disclosed. The system includes a defect inspection tool, a topography measurement tool and a processor. The defect inspection tool evaluates an underlying material such as a semiconductor substrate to identify a location associated with one or more defects and transmits the location data to the processor. The processor then uses the location data to control the positioning of the topography measurement tool in order to collect depth or height data. The topography measurement tool identifies the depth or height associated with the one or more defects and transmits the defect depth/height data to the processor. After the film to be measured is formed over the underlying material, the processor and topography measurement tool again interface to collect the defect depth/height data associated with the one or more defects which are reproduced in the overlying film. Using the defect depth/height data, the processor determines the film thickness without the need for film characterization data, thus substantially facilitating process development associated with new materials.
To the accomplishment of the foregoing and related ends, the invention comprises the features hereinafter fully described and particularly pointed out in the claims. The following description and the annexed drawings set forth in detail certain illustrative embodiments of the invention. These embodiments are indicative, however, of but a few of the various ways in which the principles of the invention may be employed. Other objects, advantages and novel features of the invention will become apparent from the following detailed description of the invention when considered in conjunction with the drawings. | {
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1. Field of the Invention
The present invention relates to a composite layered chip package that includes a plurality of subpackages stacked and a method of manufacturing the same.
2. Description of the Related Art
In recent years, a reduction in weight and an improvement in performance have been demanded of mobile devices typified by cellular phones and notebook personal computers. Accordingly, there has been a demand for higher integration of electronic components for use in mobile devices. Higher integration of electronic components has been demanded also for achieving an increase in capacity of semiconductor memory.
As an example of highly integrated electronic components, a system-in-package (hereinafter referred to as SiP), especially an SiP utilizing a three-dimensional packaging technology for stacking a plurality of semiconductor chips, has attracting attention in recent years. In the present application, a package that includes a plurality of semiconductor chips (hereinafter, also simply referred to as chips) stacked is called a layered chip package. Since the layered chip package allows a reduction in wiring length, it provides the advantage of allowing acceleration of the operation of circuits and a reduction in stray capacitance of wiring, as well as the advantage of allowing higher integration.
Major examples of the three-dimensional packaging technology for fabricating a layered chip package include a wire bonding method and a through electrode method. According to the wire bonding method, a plurality of chips are stacked on a substrate, and a plurality of electrodes formed on each chip are connected to external connecting terminals formed on the substrate by wire bonding. According to the through electrode method, a plurality of through electrodes are formed in each of the chips to be stacked and inter-chip wiring is performed through the use of the through electrodes.
The wire bonding method has the problem that it is difficult to reduce the distance between the electrodes so as to avoid contact between wires, and the problem that the high resistances of the wires hinder the acceleration of the operation of circuits.
The through electrode method is free from the above-mentioned problems of the wire bonding method. Unfortunately, however, the through electrode method requires a large number of steps for forming the through electrodes in chips, and consequently increases the cost for the layered chip package. According to the through electrode method, forming the through electrodes in chips requires a series of steps as follows: forming a plurality of holes for the plurality of through electrodes in a wafer that is to be cut later into a plurality of chips; forming an insulating layer and a seed layer in the plurality of holes and on the top surface of the wafer; forming a plurality of through electrodes by filling the plurality of holes with metal such as Cu by plating; and removing unwanted portions of the seed layer.
According to the through electrode method, the through electrodes are formed by filling metal into holes having relatively high aspect ratios. Consequently, voids or keyholes are prone to occur in the through electrodes due to poor filling of the holes with metal, so that the reliability of wiring formed by the through electrodes tends to be reduced.
According to the through electrode method, an upper chip and a lower chip are physically joined to each other by connecting the through electrodes of the upper and lower chips by means of, for example, soldering. The through electrode method therefore requires that the upper and lower chips be accurately aligned and then joined to each other at high temperatures. When the upper and lower chips are joined to each other at high temperatures, however, misalignment between the upper and lower chips can occur due to expansion and contraction of the chips, which often results in electrical connection failure between the upper and lower chips.
U.S. Pat. No. 5,953,588 discloses a manufacturing method for a layered chip package as described below. In this method, a plurality of chips cut out from a processed wafer are embedded into an embedding resin and then a plurality of leads are formed to be connected to each chip, whereby a structure called a neo-wafer is fabricated. Next, the neo-wafer is diced into a plurality of structures each called a neo-chip. Each neo-chip includes one or more chips, resin surrounding the chip(s), and a plurality of leads. The plurality of leads connected to each chip each have an end face exposed at a side surface of the neo-chip. Next, a plurality of types of neo-chips are laminated into a stack. In the stack, the respective end faces of the plurality of leads connected to the chips of each layer are exposed at the same side surface of the stack.
Keith D. Gann, “Neo-Stacking Technology”, HDI Magazine, December 1999, discloses fabricating a stack by the same method as U.S. Pat. No. 5,953,588, and forming wiring on two side surfaces of the stack.
The manufacturing method disclosed in U.S. Pat. No. 5,953,588 involves a number of process steps and this raises the cost for the layered chip package. According to the method, after the plurality of chips cut out from a processed wafer are embedded into the embedding resin, the plurality of leads are formed to be connected to each chip to thereby fabricate the neo-wafer, as described above. Accurate alignment between the plurality of chips is therefore required when fabricating the neo-wafer. This is also a factor that raises the cost for the layered chip package.
U.S. Pat. No. 7,127,807 B2 discloses a multilayer module formed by stacking a plurality of active layers each including a flexible polymer substrate with at least one electronic element and a plurality of electrically-conductive traces formed within the substrate. U.S. Pat. No. 7,127,807 B2 further discloses a manufacturing method for a multilayer module as described below. In the manufacturing method, a module array stack is fabricated by stacking a plurality of module arrays each of which includes a plurality of multilayer modules arrayed in two orthogonal directions. The module array stack is then cut into a module stack which is a stack of a plurality of multilayer modules. Next, a plurality of conductive lines are formed at the respective side surfaces of the plurality of multilayer modules included in the module stack. The module stack is then separated into individual multilayer modules.
With the multilayer module disclosed in U.S. Pat. No. 7,127,807 B2, it is impossible to increase the proportion of the area occupied by the electronic element in each active layer, and consequently it is difficult to achieve higher integration.
For a wafer to be cut into a plurality of chips, the yield of the chips, that is, the rate of conforming chips with respect to all chips obtained from the wafer, is 90% to 99% in many cases. Since a layered chip package includes a plurality of chips, the rate of layered chip packages in which all of the plurality of chips are conforming ones is lower than the yield of the chips. The larger the number of chips included in each layered chip package, the lower the rate of layered chip packages in which all of the chips are conforming ones.
A case will now be considered where a memory device such as a flash memory is formed using a layered chip package. For a memory device such as a flash memory, a redundancy technique of replacing a defective column of memory cells with a redundant column of memory cells is typically employed so that the memory device can normally function even when some memory cells are defective. The redundancy technique can also be employed in the case of forming a memory device using a layered chip package. This makes it possible that, even if some of memory cells included in any chip are defective, the memory device can normally function while using the chip including the defective memory cells. Suppose, however, that a chip including a control circuit and a plurality of memory cells has become defective due to, for example, a wiring failure of the control circuit, and the chip cannot function normally even by employing the redundancy technique. In such a case, the defective chip is no longer usable. While the defective chip can be replaced with a conforming one, it increases the cost for the layered chip package.
US 2007/0165461 A1 discloses a technique of identifying one or more defective flash memory dies in a flash memory device having a plurality of flash memory dies, and disabling memory access operations to each identified die.
In the case of forming a memory device using a layered chip package, one or more defective chips included in the layered chip package may be identified and disabled in the same way as the technique disclosed in US 2007/0165461 A1.
If, however, a layered chip package including a predetermined number of chips is able to implement a memory device having a desired memory capacity only when all the chips included in the layered chip package are conforming, simply disabling a defective chip included in the layered chip package cannot achieve the implementation of the memory device having such a desired memory capacity. | {
"pile_set_name": "USPTO Backgrounds"
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Submicron manufacturing uses lithographic techniques to build up layers of materials on a substrate to create transistors, diodes, light-emitting diodes (LEDS), capacitors, resistors, inductors, sensors, wires, optical wires, microelectromechanical systems (MEMS) and other elements which collectively produce a device that serves some function. Substrate lithography is a printing process in which a mask, sometimes called a reticle, is used to transfer patterns to a substrate to create the device. In the production or manufacturing of a device, such as an integrated circuit or a flat panel display, substrate lithography may be used to fabricate the device. When the device to be created is an integrated circuit, typically the substrate is a silicon wafer. In creating an integrated circuit, the lithography is semiconductor lithography which for high volume production is typically a substrate lithography. Other substrates could include flat panel displays, liquid panel display, a mask for flat panel display, nanoimprint masters, or other substrates, even other masks.
In semiconductor lithography, the mask or multiple masks may contain a circuit pattern corresponding to an individual layer, or a part of a layer in multiple patterning processes, of the integrated circuit. This pattern can be imaged onto a certain area on the substrate that has been coated with a layer of radiation-sensitive material known as photoresist or resist. Once the patterned layer is transferred the layer may undergo various other processes such as etching, ion-implantation (doping), metallization, oxidation, and polishing. These processes are employed to finish an individual layer in the substrate. If several layers are required, then the whole process or variations thereof will be repeated for each new layer. Eventually, a combination of multiples of devices, which may be integrated circuits, will be present on the substrate. These devices may then be separated from one another by dicing or sawing and then may be mounted into individual packages.
Optical lithography may be 193 nm light, with or without immersion, or extreme ultraviolet (EUV) or X-ray lithography, or any other frequencies of light or any combination thereof.
Optical lithography that uses 193 nm light waves works with refractive optics and transmissive photomasks or reticles. The masks block, partially block, or transmit the light waves selectively on to a substrate, which is typically resist-coated during the lithographic process, to partially expose or to expose different parts of the substrate or some material on the substrate. The masks are typically at 4× magnification of the target substrate dimensions.
Extreme Ultraviolet Lithography (EUV) uses approximately 13.5 nm wavelength of light with reflective optics. Some implementations use an anamorphic mask with magnifications of 8× in one dimension and 4× in the other dimension.
In general, smaller wavelengths of light are able to resolve finer geometries, finer spaces in between geometries, and a higher frequency (density) of features on the substrate. Also in general, smaller wavelengths of light are more difficult to reliably produce and control. Economically, it is best to use the largest wavelength of light that is able to resolve the feature sizes, spaces, and frequencies that are needed for the device. It is therefore of interest to enhance the resolution achievable on the substrate with any given wavelength(s) of light.
For any lithography of a particular resolution, additional techniques such as off-axis illumination, phase shift masks, and multiple patterning extend the resolution capabilities. When multiple patterning is used, a single substrate layer is exposed multiple times, each time using a different mask which is called a mask layer.
Masks are created by electron beam (eBeam) machines, which shoot electrons at a photo resist coating a surface, which is then processed to produce the desired openings in the mask. The amount of energy delivered to a spot on the mask is called the dose, which may have no energy at a dose set to 0.0 and a nominal dose set to 1.0 by convention. A pattern will be registered when the dose exceeds a certain threshold, which is often near 0.5 by convention. Critical dimension (CD) variation is, among other things, inversely related to the slope of the dosage curve at the resist threshold, which is called edge slope or dose margin.
There are a number of technologies used by eBeam machines. Three common types of charged particle beam lithography are variable shaped beam (VSB), character projection (CP), and multi-beam projection (MBP). The most commonly-used system for leading edge mask production is VSB. VSB and CP are sub-categories of shaped beam charged particle beam lithography, in which an electron beam is shaped by a series of apertures and steered to expose a resist-coated surface. MBP uses plurality of charged particle beams whereas VSB and CP machines typically have a single beam.
It is difficult to print features whose size is similar to or smaller than the wavelength of the light used for lithography. The industry has applied various techniques to address the difficulty of reliably printing a desired shape on the substrate. A computational lithography field has emerged to use computing to enhance the substrate lithography, which in semiconductor lithography is also referred to as wafer lithography. Reticle Enhancement Technologies (RET) include computational methods and systems to design the target reticle shapes with which to project the desired pattern on the substrate more precisely and more reliably across manufacturing variation. RET often use computation to enhance an image on a mask, to print a desired substrate pattern more accurately and more reliably with resilience to manufacturing variation. The two common techniques in RET are Optical Proximity Correction (OPC) and Inverse Lithography Technology (ILT). OPC and ILT are often iterative optimization algorithms that adjust parameters defining the mask until the predicted pattern on wafer is within acceptable tolerances for a set or a range of conditions. OPC manipulates mask geometries and simulates the wafer pattern near target edges. ILT manipulates the mask transmission as pixels, and ILT typically simulates the entire wafer pattern, a process known as dense simulation. An iterative optimization algorithm typically consists of: (1) evaluate a proposed solution to assign a cost which is trying to be minimized; (2) if cost is below a cost criteria, stop; (3) calculate a gradient for each element of the proposed solution which would lead to a lower cost; (4) adjust the proposed solution according to the calculated gradients; (5) go back to (1). Costs are typically defined with positive values where zero is the best possible score as assumed here. However, alternative cost definitions may be used.
RET in general means to improve the printability of all desired features at nominal (expected) manufacturing conditions and within expected manufacturing variation around the nominal manufacturing conditions. Since manufacturing processes are not perfect, the design needs to be resilient to certain expected manufacturing variation. A larger process window means more resiliency to manufacturing variation, specifically that pattern discrepancies through defocus and dose variation are within an acceptable tolerance. Providing sufficient process window for as many of the features as possible is a goal of RET. The percentage of chips that function as specified after fabrication is often referred to as the yield. Many factors affect yield. Improving the process window is generally considered among those skilled in the art to correlate to improving yield. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The invention relates to a packer apparatus which is adapted for use in corrosive environments within subterranean wells.
2. Description of the Prior Art
In-situ mining and in-situ leaching are synonymous processes employed to extract minerals from the earth without the removal of the ore body. These processes involve injection of a suitable fluid into the ore deposit in order to dissolve the valuable mineral, and lifting the mineral-laden fluid to the surface for extraction. Although somewhat similar to water flooding operations, in-situ mining is distinctly different from water flooding because of the exposure to and use of highly corrosive fluids, often called lixiviants, such as sulfuric acid solutions. These solutions are injected into an injection well for removal of an ore deposit, such as copper or uranium, from within one of several production wells, which may encircle the injection well. The corrosive fluids are chosen to dissolve portions of the ore body. Any lixiviant capable of reacting with and dissolving copper, unranium or other minerals usually will be very corrosive to conventional oil field equipment.
Because of the corrosive environment of such wells, the casing string must be made of a material which is resistant to the adverse effects of highly corrosive materials, such as sulfuric acid solutions. Typical of such materials is casing made of a fiberglass reinforced epoxy resin. However, because of the malleable nature of such casing, conventional packers, utilizing slip assemblies having teeth members protruding thereon for grasping around the internal diameter of the casing, are undesirable for such purposes.
The present invention provides a packer assembly which may be anchored in such a well without the use of slips, by utilization of a collet mechanism which is received within a recess defined on the casing string for anchoring engagement of the packer assembly. The metallic components of the packer assembly preferably may be made of stainless steel, or other non-corrosive material. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The invention relates in general to elevator systems, and more specifically to elevator systems having a plurality of elevator cars under group supervisory control.
2. Description of the Prior Art
It is common in prior art elevator systems which include a plurality of elevator cars under the supervision of group supervisory control, to improve elevator service by including one or more parking features. For example, in a zone oriented system, a non-busy zone car may be parked at a predetermined floor of its zone with its doors closed and the hall lanterns off. In another type of system, a non-busy car may be parked at a floor located approximately at the midpoint of the building, with its doors closed and hall lanterns off. In buildings which regularly vacate a predetermined floor at a predetermined time of the day, a clock may be used to park or "spot" one or more cars at the floor just prior to the start of the service demand from that floor. Demand features may also utilize actual evidence of a demand peak from a floor to automatically dispatch another car to the floor. For example, if two elevator cars leave a floor with a full load within a predetermined period of time, the system may send available cars to the floor, with one parking at the floor with its doors closed and hall lanterns off while another car serves the floor. When the car serving the floor closes its doors in preparation to leave the floor, the parked car will open its doors and turn on its appropriate hall lantern. When a car leaves this floor with less than a predetermined load, it cancels the demand for this floor.
Certain of these methods are statistical in nature. The dispatching logic is never quite sure whether more than one car is needed to satisfy a demand; or, what time of the day a demand will actually occur; or, what duration the demand will have. Still other methods have an inherent time lag, as a demand has to actually occur before the system responds to accommodate it. Further, if a tenant, for security reasons, for example, would like to have a car at a particular floor at a given time of day, the prior art elevator systems do not have an easily implemented arrangement for satisfying this need. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The present invention generally relates to a noise suppressor for electronic signals, and more particularly to a noise suppressor containing Aluminum Oxide (Al2O3) that is sintered under high temperature and then becomes ceramic Aluminum Oxide (Al2O3).
2. Description of the Prior Art
In traditional audio components or audio devices, such as players, amplifiers, speakers, microphones, earphones, cellular phones, sound cards in computers, wireless audio devices, television sets, or transmission cables, electronic signals are liable to external environment, such as radio frequency (RF), static electricity, or radiation in ambient air, therefore resulting in noise. The electronic signals are also liable to the noise generated in the transmission cables or electronic components/circuits in the audio devices, therefore decreasing the quality of sound or even resulting in distortion.
Take transmission cables of a home audio equipment for example. As the electronic signals processed by the player and the power amplifier are outputted and sent to speakers via the transmission cables, the impedance, capacitance, and inductance phenomena of the transmission cables may degrade the electronic signals and cause phase mismatch between right and left channel. Furthermore, the aforementioned external environment and the electronic components/circuits in the audio devices may also cause to attach a multitude of noises to the electronic signals. The disadvantages mentioned above may be improved by utilizing specific transmission cables with high transmission efficiency and utilizing shielded cables. However, such practice is costly and extravagant, and thus is generally not a plausible one. Further, the problems still maintain while the noises generated by the aforementioned external environment and the electronic components/circuits in the audio devices could not be overcome by the specific cables.
In addition to the audio components and audio devices, the fields other than the audio, such as the process or transmission of electronic signals in video components or devices, possess similar problems to be conquered. For the reasons discussed above, a need has arisen to propose an uncomplicated and efficient noise suppressor for electronic signals to lessen noise interference on the electronic signals during their process and transmission. | {
"pile_set_name": "USPTO Backgrounds"
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Field of the Invention
This invention relates to curable epoxy resins having increased adhesive strength; and, more particularly, to amine cured epoxy resins containing certain amino terminated polyether succinimide additives. | {
"pile_set_name": "USPTO Backgrounds"
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This invention relates to signalling systems generally and particularly to an audible alarm for use on the person.
A problem faced by many runners at one time or another and especially by women joggers is the possibility of attack, particularly at night, which is the only time many people can run.
When attacked, the victim may be within sight or sound of others until thrown down and when thrown down usually cannot reach freely to sound an alarm if one is carried on the person.
Alarms which are or could be carried on the person are known, as evidenced in the prior art by the following U.S. Pat. Nos.
4,121,160 to T. R. Cataldo, Oct. 17, 1978, discloses a miniature radio alarm transmitter which has a switch button; PA1 4,080,595 to L. J. Rosen, Mar. 21, 1978, discloses a miniature battery powered audible alarm which has a switch contact movable by a button; PA1 3,777,086 to O. Riedo, Dec. 5, 1972, discloses a shoe mounted alarm system in which the toe actuates the switch within the shoe, sounding an alarm at a remote location; PA1 3,702,999 to I. A. Grandisar, Nov. 14, 1972, discloses another form of shoe mounted warning system; this signals excess weight; PA1 3,614,763 to A. Yannuzzi, Oct. 19, 1971, discloses an electric audible alarm for personal use actuated when the wearer falls to the ground; PA1 3,248,723 to K. H. Miethe, Apr. 26, 1966, discloses a wearable flashlight type alarm sounder with mercury switch control; PA1 3,226,705 to P. Kaufman er al, Dec. 28, 1965, discloses a battery powered intruder alarm; PA1 568,532 to I. L. Hauser, Sept. 29, 1896, discloses a mechanical alarm of small size, and PA1 477,940 to J. F. Hurd, June 23, 1892, discloses an electric pickpocket alarm. | {
"pile_set_name": "USPTO Backgrounds"
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A common mechanical not-contacting face seal knew so far according to a German patent descriptions nr 3722303 has get a sliding ring which possesses on the face surface spiral grooves of a transverse section diminishing from its start towards the inner end, and at the same time at the very inner end of each groove the surface of the section as well as the depth of the curve equal zero. The bottom of the groove runs alongside the lateral-working surface of a sliding ring.
Non-contacting face seals, according to the invention, possess the sliding rings with grooves which have at the end a recess to the lateral plane of sliding rings amounting to approx. 7 xcexcm, while the surface of the groove bottoms longitudinal section runs alongside the curve of a max. increase of approx. 4 xcexcm, and in transverse section of the grooves the surface of the bottom runs also alongside the curve of the increase of approx. 4 xcexcm however in this transverse section both lateral edges of the bottom, are parted from the lateral plane of sliding rings by the depth, one of which is more dimensionally distant from the lateral plane of sliding rings that the second depth and the bigger depth equals up to 7 xcexcm. Geometry of the grooves of the sliding rings in transverse and longitudinal sections is constructionally connected with the shape: known in the nature of one way spiral grooves, double crossed spiral grooves, X-shaped single crossed spiral grooves, spiral grooves set in the form of the letter A oriented in the direction forward middle part of sliding rings, as well as connected constructionally with grooves which from the view are the lateral plane of the sliding rings have the shape of surfaces limited by xcexa9 letter shape.
The seals in question enable less labour consuming manufacturing of sliding rings on machines of simple construction than an specialised grinders or laser machine tools, maintaining high accuracy and dimensional repeatability of all grooves in given sliding rings. | {
"pile_set_name": "USPTO Backgrounds"
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This invention relates to a method for producing therapeutically-effective proteins as well as the means used therein, in particular syringes.
Therapeutically-effective proteins, such as erythropoietin, insulin or interferon, have been known for a long time. Many of these proteins are already registered drugs and accordingly are commonly used. Because of the high cost connected with the development and registration of these medications, there is however a need for simple and inexpensive alternatives for the preparation of therapeutically-effective proteins. In addition, not all therapeutically-effective proteins are registered drugs. However, there nevertheless frequently is the requirement to administer these proteins as well as patients. Of particular importance in this context are autologous, that is intrinsic, body proteins because of their presumed good bodily tolerance. Among these proteins are interleukin 1 receptor antagonist, interleukin-4, interleukin-10 and tumour necrosis factor receptor Type I or Type II.
The stimulation of monocytes by adherent immunoglobulin G for the formation of interleukin 1 receptor antagonists is described by Arend and Leung in Immunological Reviews (1994) 139, 71-78 and Moore et al. in Am. J. Respir. Cell Mol. Biol. (1992) 6, 569-575. Andersen et al., in Autoimmunity (1995) 22, 127-33, explained that the therapeutic effect of immunoglobulin G to be observed in vivo cannot be put down to an intensified formation of interleukin 1 receptor antagonist, and that the in vitro formation of interleukin 1 receptor antagonist (IRAP, IL-Ira) occurs by means of monocytes in dependence on serum and plasma components absorbed in polypropylene. Methods of producing IL-Ira directly usable in therapy are not described in these publications.
The underlying technical problem of this invention therefore consists in providing a method and means for preparing therapeutically-effective proteins which serve as inexpensive and rapidly implemented alternatives to the use and preparation of conventional drug preparations.
The invention solves this problem by providing a method for preparing at least one therapeutically-effective protein or a protein mixture in a syringe, in which the inner structures of the syringe are coated with inductors, in particular immunoglobulins, the syringe is filled with a body fluid of a patient, incubated and the therapeutically-effective protein is formed in the body fluid. The invention therefore provides in a first procedure step that the inner structures of the syringe are coated with inductors, in particular immunoglobulins, and these are fixed there. After coating, the syringe is filled in a second procedure step with a body fluid, in particular blood, lymph fluid, saliva or turine, and incubated. Preferably the body fluid is taken with the syringe directly from the patient. The inductors fixed to the inner structure of the syringe, in particular immunoglobulins, induce specifically in the body fluid, i.e. depending on the inductor used, in particular immunoglobulin, and the body fluid used, the formation of therapeutically-effective proteins which are accordingly accumulated, or that is to say formed in the body fluid in the syringe. The body fluid accumulated in this way can be stored in sterile conditions in the syringe and resupplied as or when required to the patient directly without additional treatment or for example after centrifuging and/or sterile filtration.
The invention also provides that the formation of several proteins is induced simultaneously in a body fluid, so that a body fluid is formed which has a raised concentration of several proteins.
In the context of this invention, an inner structure of a syringe is taken to mean any area or any structure of the syringe, which inner structure is inside the syringe and which comes into contact with the body fluid to be contained and which can be coated with inductors, in particular immunoglobulins. Particularly advantageous is the inner structure of a syringe whose inner surface optionally is a surface with a structure for expanding the surface area. The inner structure can however be formed either alternatively or additionally by particles, spheres, gels, glass wool, granulated material or similar, in order to make available a greater surface area for the inductors, in particular immunoglobulins.
In a particular advantageous design of the invention, provision is made for the syringe, in particular the inner structure of the syringe, to be made of polystyrene, polypropylene, glass or a similar material, i.e. consists of these materials or essentially contains these materials, so long as this material processes inductor-binding, in particular immunoglobulin-binding, properties, that is to say adhesion of the inductors, in particular immunoglobulins, is possible. A preferred form of implementation of the invention provides for the production of the inner structure of the syringe, while the inherently non-protein-binding inner structure of the syringe is provided with a protein-binding coating.
This invention is advantageous inasmuch as that an easily implemented method is provided, by which autologous therapeutically-effective proteins, capable of preparation by induction, in particular immunoglobulin induction, can be prepared and in the form prepared this way, i.e. together with the other components of the body fluids in the syringe, can be administered directly to the patient, i.e. without further manipulation such as transfer to another container, for example. If necessary, centrifuging and/or sterile filtration can be provided for separating solid components. The use of commercially available and often expensive drugs is therefore unnecessary. Furthermore, the use of therapeutically-effective autologous proteins is possible which until now have not been legally authorized drugs and therefore not legally available. Finally the invention, which is based on the drug preparation taking place outside the patient, proves to be advantageous in that contamination, impurities, infection or similar of the therapeutically-effective proteins, are avoided.
In a particularly preferred form of implementing this invention, the therapeutically-effective protein is interleukin 4, interleukin 10 or soluble tumour necrosis factor receptor Type I or Type II, especially preferred being interleukin 1 receptor antagonist (or IL-Ira).
In another especially preferred form of implementing this invention, immunoglobulin G is the immunoglobulin with which the inner structure of the syringe is coated. In the context of this invention, immunoglobulin G is understood to mean isolated immunoglobulin G but also immuno-complexes containing immunoglobulin G, preparations containing immunoglobulin G such as sera, plasma or immunoglobulin G Fc fragment, or preparations or complexes containing the latter.
This invention therefore provides, in a particularly preferred form of implementation, for a method of preparing interleukin 1 receptor antagonists, whereby the inner structure of a syringe is coated with an inductor, in particular an immunoglobulin, and especially preferred immunoglobulin G, the syringe is filled with a body fluid, preferably blood, is incubated and the interleukin 1 receptor antagonist is formed and accumulated in the body fluid. Through the binding or adhesion of the inductor, in particular immunoglobulin G, on the surface of the inner structure of the syringe, the latter is in a position to stimulate the monocytes in the blood to form interleukin 1 receptor antagonist, so that this is accumulated in the blood. After incubation, i.e. after accumulation of the interleukin 1 receptor antagonist, the blood in the syringe can be supplied without further manipulation, such as transferring into another container for example, directly to the patient from whom the blood put into the syringe had been taken. For separation of solid components, such as cells, centrifuging and/or sterilization can be advantageously provided. The invention therefore also provides that the blood can be taken from the patient by means of the inductor-coated, in particular immunoglobulin G-coated, syringe, the blood can be incubated in the syringe and, after IL-ira information, can be supplied to the patient again with the syringe. Such a procedure is, for example, especially advantageous in the field of neuro-orthopaedics, i.e. for example in the case of neurologically-caused back complaints. Hitherto only an intervertebral disc operation, cortisone treatments, irrigation procedures using saline solutions or similar, were considered for the treatment of this type of complaint. This invention now allows the simple and inexpensive provision of a therapeutically-effective protein for treating these complaints.
In another preferred form of implementations, the invention provides that the inner structure of the syringe is coated additionally with anticoagulants, in particular heparin. According to the invention, the anticoagulation can also be provided not as a coating but to be introduced uncombined in the container, for example to be put into the syringe in the dry frozen or liquefied state.
In another preferred form of implementation, the invention provides for the incubation of the body fluid in the syringe over a period of 12 to 72 hours, preferably carried out at an ambient temperature up to 41xc2x0 C., in particular 37xc2x0 C.
In one form of the invention, the invention also provides that after the formation of the therapeutically-effective protein in the body fluid, the body fluid is further processed in order to separate for example certain components of the latter, for example blood plasma or blood platelets. This separation process can be performed, in a preferred form of implementation of the invention, by centrifuging.
In a further form of implementation, the invention concerns a method of producing a syringe, suitable for in vitro induction of interleukin 1 receptor antagonists, in which an inductor, preferably an immunoglobulin, in particular immunoglobulin G, is placed in the syringe with a protein-binding inner structure and incubated so that the inductor, in particular the immunoglobulin G, binds to the inner structure.
It is self-evident that the invention also concerns the syringe produced in this way, which is manufactured in a particularly preferred form of implementation from polystyrene, polypropylene or glass, the syringe being distinguished by a coating of its inner structure with an inductor, in particular with an immunoglobulin, preferably with immunoglobulin G.
The invention also relates to the use of immunoglobulin, in particular immunoglobulin G, for coating the inner structures of syringes, preferably made of polystyrene, polypropylene or glass, for the in-vitro induction of therapeutically-effective proteins, preferably interleukin 1 receptor antagonists.
Additional advantageous forms of the invention emerge from the sub-claims.
The invention is explained in more detail with reference to figures and examples of implementation. | {
"pile_set_name": "USPTO Backgrounds"
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A gas lift valve may be implemented in a gas lift system, for example, to control flow of lift gas into a production tubing conduit. As an example, a gas lift valve may be located in a gas lift mandrel, which may provide for communication with a lift gas supply, for example, in an annulus (e.g., between production tubing and casing). Operation of a gas lift valve may be determined, for example, by preset opening and closing pressures in the tubing or annulus. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The present invention relates to jacks and more particularly pertains to a new dual hydraulic jack system for more quickly raising the jack up to a load to be lifted.
2. Description of the Prior Art
The use of jacks is known in the prior art. More specifically, jacks heretofore devised and utilized are known to consist basically of familiar, expected and obvious structural configurations, notwithstanding the myriad of designs encompassed by the crowded prior art which have been developed for the fulfillment of countless objectives and requirements.
Known prior art includes U.S. Pat. No. 4,161,229; U.S. Pat. No. 5,918,860; U.S. Pat. No. 5,975,496; U.S. Pat. No. 5,186,094; U.S. Pat. No. 4,506,867; and U.S. Pat. No. Des. 313,492.
While these devices fulfill their respective, particular objectives and requirements, the aforementioned patents do not disclose a new dual hydraulic jack system. The inventive device includes a base and a dual pump assembly mounted on a top of the base. The dual pump assembly comprises an inner piston assembly movably positioned in a first fluid chamber and an outer piston assembly movably positioned in a second fluid chamber. A jack assembly is provided for lifting a load. The jack assembly includes a jack piston assembly that is movably positioned in a third fluid chamber. A reservoir is provided for holding fluid in an interior of the reservoir. A first fluid channel is provided for providing fluid communication between the first, second and third fluid chambers. A second fluid channel is provided for providing fluid communication between the reservoir and the first and second fluid chambers. A first conduit is provided for providing fluid communication between the reservoir and the third fluid chamber. A plurality of valves is provided for controlling unidirectional flow of the fluid through the first and second fluid channels.
In these respects, the dual hydraulic jack system according to the present invention substantially departs from the conventional concepts and designs of the prior art, and in so doing provides an apparatus primarily developed for the purpose of more quickly raising the jack up to a load to be lifted.
In view of the foregoing disadvantages inherent in the known types of jacks now present in the prior art, the present invention provides a new dual hydraulic jack system construction wherein the same can be utilized for more quickly raising the jack up to a load to be lifted.
The general purpose of the present invention, which will be described subsequently in greater detail, is to provide a new dual hydraulic jack system apparatus and method which has many of the advantages of the jacks mentioned heretofore and many novel features that result in a new dual hydraulic jack system which is not anticipated, rendered obvious, suggested, or even implied by any of the prior art jacks, either alone or in any combination thereof.
To attain this, the present invention generally comprises a base and a dual pump assembly mounted on a top of the base. The dual pump assembly comprises an inner piston assembly movably positioned in a first fluid chamber and an outer piston assembly movably positioned in a second fluid chamber. A jack assembly is provided for lifting a load. The jack assembly includes a jack piston assembly that is movably positioned in a third fluid chamber. A reservoir is provided for holding fluid in an interior of the reservoir. A first fluid channel is provided for providing fluid communication between the first, second and third fluid chambers. A second fluid channel is provided for providing fluid communication between the reservoir and the first and second fluid chambers. A first conduit is provided for providing fluid communication between the reservoir and the third fluid chamber. A plurality of valves is provided for controlling unidirectional flow of the fluid through the first and second fluid channels.
There has thus been outlined, rather broadly, the more important features of the invention in order that the detailed description thereof that follows may be better understood, and in order that the present contribution to the art may be better appreciated. There are additional features of the invention that will be described hereinafter and which will form the subject matter of the claims appended hereto.
In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting.
As such, those skilled in the art will appreciate that the conception, upon which this disclosure is based, may readily be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions insofar as they do not depart from the spirit and scope of the present invention.
Further, the purpose of the foregoing abstract is to enable the U.S. Patent and Trademark Office and the public generally, and especially the scientists, engineers and practitioners in the art who are not familiar with patent or legal terms or phraseology, to determine quickly from a cursory inspection the nature and essence of the technical disclosure of the application. The abstract is neither intended to define the invention of the application, which is measured by the claims, nor is it intended to be limiting as to the scope of the invention in any way.
It is therefore an object of the present invention to provide a new dual hydraulic jack system apparatus and method which has many of the advantages of the jacks mentioned heretofore and many novel features that result in a new dual hydraulic jack system which is not anticipated, rendered obvious, suggested, or even implied by any of the prior art jacks, either alone or in any combination thereof.
It is another object of the present invention to provide a new dual hydraulic jack system which may be easily and efficiently manufactured and marketed.
It is a further object of the present invention to provide a new dual hydraulic jack system which is of a durable and reliable construction.
An even further object of the present invention is to provide a new dual hydraulic jack system which is susceptible of a low cost of manufacture with regard to both materials and labor, and which accordingly is then susceptible of low prices of sale to the consuming public, thereby making such dual hydraulic jack system economically available to the buying public.
Still yet another object of the present invention is to provide a new dual hydraulic jack system which provides in the apparatuses and methods of the prior art some of the advantages thereof, while simultaneously overcoming some of the disadvantages normally associated therewith.
Still another object of the present invention is to provide a new dual hydraulic jack system for more quickly raising the jack up to a load to be lifted.
Yet another object of the present invention is to provide a new dual hydraulic jack system which includes a base and a dual pump assembly mounted on a top of the base. The dual pump assembly comprises an inner piston assembly movably positioned in a first fluid chamber and an outer piston assembly movably positioned in a second fluid chamber. A jack assembly is provided for lifting a load. The jack assembly includes a jack piston assembly that is movably positioned in a third fluid chamber. A reservoir is provided for holding fluid in an interior of the reservoir. A first fluid channel is provided for providing fluid communication between the first, second and third fluid chambers. A second fluid channel is provided for providing fluid communication between the reservoir and the first and second fluid chambers. A first conduit is provided for providing fluid communication between the reservoir and the third fluid chamber. A plurality of valves is provided for controlling unidirectional flow of the fluid through the first and second fluid channels.
Still yet another object of the present invention is to provide a new dual hydraulic jack system that saves time for the user. The present invention utilizes a jacking system that uses both high and low pressure ratios to lift a load. The present invention uses dual pumps having a high-pressure ratio to more quickly move a jack assembly up to a load when there is little load pressure exerted on the jack assembly. Once pressure on the jack assembly increases one of the dual pumps stops delivering fluid to the jack assembly providing a lower pressure ratio causing the jack assembly to move less quickly thus more precisely.
Even still another object of the present invention is to provide a new dual hydraulic jack system that can reduce the potential of injury to a user due to repetitive arm or leg motions from operating a jack that has a single low-pressure ratio. Jacks having a single low-pressure ratio require a user to activate the jack relatively many more times to cover the same distance that the present invention can cover with less operation by the user. The less the user has to activate the jack the less susceptible the user will be to repetitive motion injury. | {
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1. Field of the Invention
This invention relates to an optical device for electrostatic copying machines with a copy enlarging and reducing function, and more particularly to an optical device for a copying machine in which the position of the principal point of the optical system can be inverted for copy enlargements and reductions.
2. Description of the Prior Art
Recently, electrostatic copying machines with the functions of enlarging and reducing the copy ratio form a main stream in the art. In a copying machine with such copy enlarging and reducing functions, the optical system which is interposed between an original mount and a sensitive material surface for exposure, e.g. a photosensitive drum surface, usually employs a symmetrical lens construction which has an principal point internally of the optical system like the so-called Orthometa- or Sellar-type lens. The optical system which is movable along the light path is located at a median position between the original mount and the sensitive material surface at the time of duplication in 1:1 copy ratio, shifting the optical system toward the original mount and the sensitive material surface at the time of copy enlargements and reductions, respectively, thereby varying the ratio of the light path length on the side of the object point or between the optical system and the original mount to the light path length on the side of the image point or between the optical system and the sensitive material surface according to changes in copy ratio.
In order to make the copying machine compact, more than one mirror is provided in each of the light paths on the sides of the object and image points, thereby folding the light paths in such a manner as to reduce the space for the entire light path length. In case of a copying machine of the type which has a fixed original mount and a movable light source for illuminating the original, some of the mirrors are moved to follow the movement of the light source.
Therefore, when shifting the positions of the optical system and mirrors to alter the copy ratio as mentioned hereinbefore, it is necessary to make arrangements to avoid interferences therebetween. That is to say, restrictions based on a selected range of copy ratios are imposed on the positional relationship between the optical system and the mirrors which are located forward and backward of the optical system. In this connection, although currently there is an extremely strong demand for small-sized and compact copying machines, the reduction of the machine size has a limit in view of the restrictions on the positional relationship of the optical system with the forward and backward located mirrors, which has a great influence on the dimensions of the copying machine. Otherwise, there is another problem that the designed range of the copy ratios has to be sacrificed to some extent for reduction of the machine size. | {
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Technical Field
The present disclosure relates to an image capturing optical system and an image capturing device, and more particularly, to an image capturing optical system and an image capturing device applicable to electronic devices.
Description of Related Art
As personal electronic products nowadays has been becoming more and more compact, the internal components of the electronic products are also required to be smaller in size than before. Except for the demand of miniaturization, the advanced semiconductor manufacturing technologies reducing the pixel size of sensors have also pushed compact optical systems to evolve toward the field of higher megapixels. In addition, the popularity of smart phones and tablet personal computers also significantly increases the requirements for high resolution and image quality of present compact optical systems. Therefore, there is also an increasing demand for compact optical systems featuring better image quality.
In a conventional five-element optical system, the fourth lens element generally has a convex image-side surface. However, under this configuration, the convex image-side surface of the fourth lens element has a larger curvature and the variation of the thickness of the lens is more pronounced, thus shortcomings, such as formation difficulties of lenses and excessive optical sensitivity may occur easily. Moreover, the refractive power of the second lens element in the conventional five-element optical system is usually poorly distributed and unable to effectively balance the positive refractive power of the first lens element, thus the light will bend drastically and the aberration cannot be eliminated easily.
Therefore, a need exists in the art for an optical system that features compact size, better image quality, and an appropriate sensitivity of the system. | {
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Devices and methods for performing in-vivo imaging of passages or cavities within a body are known in the art. They may include, for example, swallowable capsules which collect data and which may transmit the data to a receiver system. Such devices may also include, inter alia, various endoscopic imaging systems and devices for performing imaging in various internal body cavities.
An in-vivo imaging device may include, for example, an imaging system for obtaining images and other data from inside a body cavity or lumen, such as the gastrointestinal (GI) tract. The imaging system may include, for example, an illumination unit, such as a set of light emitting diodes (LEDs), or other suitable light sources. The device may include an imaging sensor and an optical system, which focuses the images onto the imaging sensor. A transmitter and antenna may be included for transmitting the image signals. A receiver/recorder, for example worn by the patient, may record and store image and other data. The recorded data may then be downloaded from the receiver/recorder to a computer or workstation for display and analysis.
Upon display or analysis of the images obtained from the device, it would be useful to be able to determine the size of objects viewed, such as for example tumors or polyps. | {
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Telephone calls have been automatically routed through the Public Switching Telephone Network (PSTN) for as long as modern telephone switching equipment has existed. A telephone number corresponding to World Zone 1, which includes the United States, has a three digit Numbering Plan Area code (or NPA) and a three digit Exchange code (or NXX). Each NPA/NXX represents a telephone exchange. Further, each NPA/NXX combination is controlled by an operating company, designated by an Operating Company Number (OCN).
Telephone calls originating (calling party) and terminating (called party) in telephone exchanges controlled by different operating companies are routed between operating companies. Interexchange carriers, such as long distance companies, carry communications traffic between the telephone exchanges. In the past, communications traffic consisted of voice traffic that was transmitted in analog form. More recently, communications traffic has expanded to encompass voice and data traffic that are transmitted in digital form, such as in one or more data packets.
In order to create wireline regulation, the United States and Canada were divided into Local Access and Transport Areas (LATAs). A LATA corresponds to a geographical region in which a divested Regional Bell Operating Company (RBOC) is permitted to offer exchange telecommunications and exchange access services. The interexchange carriers provide routes between LATAs. Further, Telcordia Technologies publishes the Local Exchange Routing Guide (LERG), which is a monthly guide used to determine the routing of telecommunications services between LATAs. Therefore, interexchange carriers can access the LERG to determine one or more call routing options.
The rates charged by the interexchange carriers were previously determined through contract negotiations and were typically valid for an extended period of time. Generally, once an agreement with an interexchange carrier was reached, the interexchange carrier exclusively performed call routing between one or more originating and terminating points. Alternatively, a particular interexchange carrier could be designated as the carrier for all of a subscriber's long distance telephone calls. The rates applied to interexchange routing did not change frequently, as accurate billing depended on being able to determine the applicable rate for a particular call routed through an interexchange carrier.
With the wide-spread adoption of mobile communications, however, competition between interexchange carriers increased. Service providers were able to develop routing tables that compared the rates charged by various interexchange carriers. Further, service providers could make routing decisions based on the rates charged by the interexchange carriers. Because the rates were provided and entered into the routing tables manually, however, the rates associated with an interexchange carrier were only modified periodically. | {
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JavaScript language is a scripting language for manipulating HTML documents in browsers. It has been widely adopted in a variety of Web applications to provide more accessible web pages and improve user experience. Ajax (Asynchronous JavaScript And XML) is a technology for developing Web applications that adapts a client side script and a Web server to asynchronously exchange data using the HTTP protocol. Asynchronous invocation is a feature of Ajax. By using this feature, Web applications are capable of dynamically updating contents on a Web page without refreshing the whole page. By using Ajax, a richer and more dynamic Web application user interface can be created. Its low response times and high availability can approach the properties of a local desktop application. Ajax is a part of the JavaScript 1.3 standard and is supported by most mainstream browsers. Most web applications exploit JavaScript and Ajax to provide comprehensive functionalities, rather than simply detect a browser or validate a certain form on a page.
Ajax requests sent from browsers can only handle responses from the requested domain. Back-end services that handle Ajax requests sometimes make requests to external domains. Making external domain requests from a back-end service can be problematic since it exposes the domain of the back-end server to an external domain. | {
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The present invention is for pharmaceutical compositions for transdermal delivery of N-[N-[5-[4-(aminoiminomethyl)phenyl-1-oxopentyl]-L-xcex1-aspartyl]-L-phenylalanine or its esters and their pharmaceutically acceptable salts which are useful as platelet aggregation inhibitors.
N-[N-[5-[4-(aminoiminomethyl)phenyl]-1-oxopentyl]-L-xcex1-aspartyl]-L-phenylalanine which is represented by the following formula
or its esters and their pharmaceutically acceptable salts are known to be useful as platelet aggregation inhibitors. See International Publication W092/15607, published Sep. 17, 1992.
Platelets are cellular elements found in whole blood which also participate in blood coagulation. Fibrinogen binding to platelets is important to normal platelet function in the blood coagulation mechanism. When a blood vessel receives an injury, the platelets binding to fibrinogen will initiate aggregation and form a thrombus. Interaction of fibrinogen with platelets occurs through a membrane glycoprotein complex, known as gpIIb/IIIa; this is an important feature of the platelet function. Inhibitors of this interaction are useful in modulating platelet thrombus formation.
Initially, N-[N-[5-[4-(aminoiminomethyl)phenyl]-1-oxopentyl]-L-xcex1-aspartyl]-L-phenylalanine or its esters and their pharmaceutically acceptable salts were administered orally, parenterally, rectally or by inhalation spray. See International Publication W092/15607, published Sep. 17, 1992.
These prior conventional methods of administering drugs to patients, however, possess certain shortcomings.
The oral route of drug administration, for example, is inadequate for several reasons, even if the drug is administered to the patient at periodic intervals according to a well-defined schedule.
The rate of absorption of drug through the gastrointestinal tract is affected by both the contents in the tract and the passage of time as the drug travels through the small intestine. Therefore, such variables as whether the drug is administered before or after eating, and the type and quantity of food eaten, for example, high or low fat content, or whether the drug is administered before or after bowel movement, affect the rate of absorption of the drug which takes place in the small intestine.
Additionally, the time of passage of drug through the small intestine is affected by the rate of peristaltic contraction, adding further uncertainty.
Also important is the rate of circulation of blood to the small intestine, and the fact that many drugs administered by this route are rendered inactive by gastric acid, digestive enzymes of the gastrointestinal tract, or by liver, where the drug can be metabolized to an inactive product.
These factors make it difficult to achieve a desired time course of concentration of drug in the blood.
The most inevitable result of the oral administration of drugs through the gastrointestinal tract is that the level of drug in circulation surges to a peak level shortly after the time of drug administration, followed by a decline in drug concentration in the blood and body compartments.
The administration of drugs by injection likewise entails certain disadvantages. For example, very strict asepsis must be maintained in order to avoid infection of the blood, the vascular system and the heart. Drug administration by poor intravenous technique may result in perivascular injection, when that was not intended. The typical result of injection of a drug into the blood is a sudden rise in the blood concentration of the drug followed by an uncontrollable decline in drug concentration. Additionally, administration of drugs by injection is inconvenient and painful.
Other dosage forms for systemic administration of drugs, such as rectal suppositories and sublingual lozenges, also produce non-uniform levels of the therapeutic agent in circulation. These dosage forms require great patient cooperation and have low patient acceptability, resulting in decreased patient compliance with a prescribed drug regimen, which is the most common failure of drug therapy.
The present invention is a new form of administration of N-[N-[5-[4-(aminoiminomethyl)phenyl]-1-oxopentyl]-L-xcex1-aspartyl]-L-phenylalanine or its esters and their pharmaceutically acceptable salts into a transdermal pharmaceutical composition to achieve blood levels which are effective in the inhibition of platelet aggregation. Particularly interesting compounds which are representative of this above-described class of compounds are exemplified by
N-[N-[5-[4-(aminoiminomethyl)phenyl]-1-oxopentyl]-L-xcex1-aspartyl]-L-phenylalanine, hydrochloride;
N-[N-[5-[4-(aminoiminomethyl)phenyl]-1-oxopentyl]-L-xcex1-aspartyl]-L-phenylalanine, diethyl ester;
N-[N-[5-[4-(aminoiminomethyl)phenyl]-1-oxopentyl]-L-xcex1-aspartyl]-L-phenylalanine, dimethyl ester; and
N-[N-[5-[4-(aminoiminomethyl)phenyl]-1-oxopentyl]-L-xcex1-aspartyl]-L-phenylalanine, acetate.
Transdermal delivery of N-[N-[5-[4-(aminoiminomethyl)-phenyl]-1-oxopentyl]-L-xcex1-aspartyl]-L-phenylalanine or its esters and their pharmaceutically acceptable salts offers advantages over the other methods of delivery which were discussed above. An advantage is the ease of application over the intravenous or intramuscular delivery. This convenience of use offers the benefit of a lifestyle uninterrupted by hospital visits, which are needed when administering by other known methods. Administration by IV or intramuscular delivery has certain disadvantages of inadvertent needle sticks. Needle sticks have also been associated with the risk of secondary systemic infections. Transdermal delivery does provide the ability to deliver drugs directly to general circulation. Effective transdermal delivery affords a controlled, constant, zero-order release of active compound. Transdermal delivery is greatly advantageous in that it can be used in pediatric age groups, where IV or IM dosing is very difficult.
Another advantage of transdermal delivery is that the delivery of the active can be rapidly terminated by removing the patch. Other routes of delivery do not possess this most desirable advantage.
Recognizing that the outer layer of the skin, the epidermis, protects the area under the skin from penetration of foreign chemicals, various enhancing agents have been used to deliver drugs transdermally. Substances that help promote drug diffusion through the stratum corneum and epidermis are referred to as skin-penetration enhancers, accelerants, adjuvants and absorption promoters. B. Idson, Cosmetics and Toiletries, 95, 59 (1980) states that the factors affecting drug penetration and consequently in most cases, effectiveness, are complex. The vehicle that provides ideal conditions for one drug may prove unsatisfactory for another.
Various penetration enhancers are known to be useful in transdermal drug delivery. U.S. Pat. No. 4,863,970, U.S. Pat. No. 4,722,941, U.S. Pat. No. 4,931,283 and EP 351,897 disclose some representative penetration enhancers used in transdermal compositions and for topical administration.
The present invention provides a pharmaceutical formulation in the form of a transdermal delivery system comprised of N-[N-[5-[4-(aminoiminomethyl)phenyl]-1-oxopentyl]-L-xcex1-aspartyl]-L-phenylalanine or its esters and their pharmaceutically acceptable salts and a delivery solvent. Effective delivery solvents for the practice of this invention are exemplified by ethanol and n-methyl pyrrolidone.
It is the primary object of this invention to provide a pharmaceutical composition for transdermal delivery of N-[N-[5-[4-(aminoiminomethyl)phenyl]-1-oxopentyl]-L-xcex1-aspartyl]-L-phenylalanine or its esters and their pharmaceutically acceptable salts.
This invention encompasses pharmaceutical compositions for transdermal delivery of N-[N-[5-[4-(aminoiminomethyl)phenyl]-1-oxopentyl]-L-xcex1-aspartyl]-L-phenylalanine or its esters and their pharmaceutically acceptable salts. Particularly, this invention encompasses pharmaceutical compositions of
N-[N-[5-[4-(aminoiminomethyl)phenyl-1-oxopentyl]-L-xcex1-aspartyl]-L-phenylalanine, hydrochloride; and
N-[N-[5-[4-(aminoiminomethyl) phenyl]-1-oxopentyl]-L-xcex1-aspartyl]-L-phenylalanine, diethyl ester for transdermal delivery.
The term xe2x80x9cpharmaceutically acceptable saltxe2x80x9d refers to a salt prepared by acid-base reactions. Examples of pharmacologically acceptable salts include the hydrochloride, hydrobromide, hydroiodide, sulfate, phosphate, acetate, propionate, lactate, maleate, malate, succinate, and tartrate salts. All of these salts may be prepared by conventional means known by those of ordinary skill in the art. The most preferred salt is the hydrochloride.
The term xe2x80x9cestersxe2x80x9d refers to a radical having the following formula
xe2x80x94COOR
wherein the portion defined by R refers to a linear or branched saturated hydrocarbon group having 1 to 6 carbon atoms. Illustrative of such groups are methyl, ethyl, propyl, isopropyl and butyl.
The term xe2x80x9ccompositionxe2x80x9d as used herein means a product which results from the mixing or combining of more than one element or ingredient.
The term xe2x80x9cpharmaceutically-acceptable carrierxe2x80x9d as used herein means a pharmaceutically acceptable material, composition or vehicle, such as a liquid or solid filler, diluent, excipient, or solvent involved in carrying or transporting a chemical agent from one organ or portion of the body to another organ or portion of the body.
The term xe2x80x9ctransdermal deliveryxe2x80x9d as used herein means administration of the pharmaceutical composition topically to the skin wherein the active ingredient, or its pharmaceutically acceptable salts, will be percutaneously delivered in a therapeutically effective amount.
The term xe2x80x9cpenetration enhancersxe2x80x9d as used herein means compounds which enhance the percutaneous absorption of drugs. Selection of an effective penetration enhancer for a particular drug must be experimentally deduced. A penetration enhancer which works for one drug will not necessarily work for every other drug B. Idson, Cosmetics and Toiletries, 95, 59 (1980).
The term xe2x80x9cdelivery solventxe2x80x9d as used herein means a solvent in which the dissolution (dissolving of the active or compound into the solvent) is complete.
In the present invention N-[N-[5-[4-(aminoiminomethyl)-phenyl]-1-oxopentyl]-L-xcex1-aspartyl]-L-phenylalanine or its esters and their pharmaceutically acceptable salts are administered transdermally by topical application of N-[N-[5-[4-(aminoiminomethyl)phenyl]-1-oxopentyl]-L-xcex1-aspartyl]-L-phenylalanine or its esters and their pharmaceutically acceptable salts to the skin. More preferably these compounds can be administered in the form of a gel and covered with a suitable impenatrable membrane. The pharmaceutical compositions of the present invention can administer the N-[N-[5-[4-(aminoiminomethyl)phenyl]-1-oxopentyl]-L-xcex1-aspartyl3-L-phenylalanine or its esters and their pharmaceutically acceptable salts in admixture with a delivery solvent and suitable pharmaceutical diluents, carriers and excipients such as gelling agents, emollients, (i.e., allantoin and preservatives (i.e., parabens). Preferably N-[N-[5-[4-(aminoiminomethyl)-phenyl]-1-oxopentyl]-L-xcex1-aspartyl]-L-phenylalanine or its esters and their pharmaceutically acceptable salts are administered in admixture with a delivery solvent.
Delivery solvents suitable for the delivery of N-[N-[5-[4-(aminoiminomethyl)phenyl]-1-oxopentyl]-L-xcex1-aspartyl]-L-phenylalanine or its esters and their pharmaceutically acceptable salts are ethanol and N-methyl pyrrolidone. A preferred solvent is ethanol. The solvents are present in the range of 75 to 95%.
The practicality of administering a given drug percutaneously on a continuous basis depends upon the concentration of drug in the blood that is required to provide the desired pharmacologic effect, the degree to which the skin is permeable to the drug, and the amount of skin surface area that is available for drug administration.
The skin surface area which is available for drug administration, while theoretically being unlimited, is, for practical reasons, typically confined to a range Of from about 1 square centimeters to about 100 square centimeters. With the available skin surface area fixed within this range, the matter then narrows as to whether sufficient drug will pass through the defined skin surface area to provide the desired therapy. If it will, then it may not be difficult to effectively administer the drug percutaneously. If, however, the inherent permeability of the skin to the drug is so high or so low that too much or too little drug will pass through that area of skin, then the rate of administration of the drug to the skin must be controlled, or the permeability of the skin to the drug must be increased, as the case may be, to take percutaneous administration practical.
In order to inhibit platelets from aggregating, use of a non-toxic but therapeutically effective amount of a N-[N-[5-[4-(aminoiminomethyl)phenyl]-1-oxopentyl]-L-xcex1-aspartyl]-L-phenylalanine or its esters and their pharmaceutically acceptable salts is employed. The dose regimen for inhibiting platelet aggregation is selected in accordance with a variety of factors including the type, age, weight, sex and medical condition of the patient. A physician of ordinary skill can readily determine and prescribe an effective amount of the drug required to prevent or treat the progress of condition.
In order to achieve the desired therapeutic effect N-[N-[5-[4-(aminoiminomethyl)phenyl]-1-oxopentyl]-L-xcex1-aspartyl]-L-phenylalanine or its esters and their pharmaceutically acceptable salts parenterally, a dose of 10-50 mg/day is administered. N-[N-[[5-[4-(aminoiminomethyl)phenyl]-1-oxopentyl-L-xcex1-aspartyl]-L-phenylalanine or its esters and their pharmaceutically acceptable salts administered transdermally achieves similar plasma concentrations as the parenteral route of administration. In the preferred embodiment of the present invention N-[N-[5-[4-(aminoiminomethyl)phenyl]-1-oxopentyl]-L-xcex1-aspartyl]-L-phenylalanine or its esters and their pharmaceutically acceptable salts are administered in an amount of 100-500 mg/patch. In a more preferred embodiment of the present invention N-[N-[5-[4-aminoiminomethyl)phenyl]-1-oxopentyl]-L-xcex1-aspartyl]-L-phenylalanine or its esters and their pharmaceutically acceptable salts are delivered in an amount of 10-50 mg/day.
These doses were selected in order to achieve blood levels equivalent to that achieved with parenteral dosing. The required dose of active ingredient to be administered will vary with, amongst other factors, the severity of the condition being treated, and will depend on whether the treatment is remedial or prophylactic.
In order to administer the dose set out above the concentration of N-[N-[5-[4-aminoiminomethyl)phenyl]-1-oxopentyl]-L-xcex1-aspartyl]-L-phenylalanine or its esters and their pharmaceutically acceptable salts in the composition can be from 1 to 20 w/w. The concentrating of N-[N-[5-[4-(aminoiminomethyl)phenyl]-1-oxopentyl]-L-xcex1-aspartyl]-L-phenylalanine or its esters and their pharmaceutically acceptable salts is however preferably from 5 to 20 w/w.
The pharmaceutical compositions of the invention can be made, for example, by addition of a gel to a solution of the phenylamidine derivative. The solution gels and can be poured into a measuring-dispensing device. The gel can be extruded into sealable gel-tubes or syringes. The gel can be applied to the skin in a measured dose, dependent on the factors discussed above and covered with an impenetrable membrane.
Alternatively, the composition can be incorporated in a transdermal patch for delivery percutaneously. Methodology and design of transdermal patches for drug delivery are well known in the pharmaceutical art. | {
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Data stored on magnetic media, such as a magnetic disks, are typically stored in encoded form, so that errors in the stored data can possibly be corrected. The errors may occur, for example, because of inter-symbol interference, a defect in the disk, or noise. As the density of the data stored on the disk increases, more errors are likely, and the system is required to correct greater numbers of errors, which include greater numbers of burst errors. A burst error is typically defined as a contiguous number of symbols in which the first symbol and the last symbol are erroneous. The speed with which the system corrects the errors, including the burst errors, is important to the overall speed with which the system processes the data.
Prior to recording, multiple-bit data symbols are encoded using an error correction code (ECC). When the data symbols are retrieved from the disk and demodulated, the ECC is employed to, as the name implies, correct the erroneous data.
Specifically, before a string of k data symbols is written to a disk, it is mathematically encoded using an (n, k) ECC to form n-k ECC symbols. The ECC symbols are then appended to the data string to form an n-symbol error correction code word, which is then written to, or stored, on the disk. When the data are read from the disk, the code words containing the data symbols and ECC symbols are retrieved and mathematically decoded. During decoding, errors in the data are detected and, if possible, corrected through manipulation of the ECC symbols [for a detailed description of decoding see, Peterson and Weldon, Error Correction Codes, 2nd Ed. MIT Press. 1972].
To correct multiple errors in strings of data symbols, the system typically uses an ECC that efficiently and effectively utilizes the various mathematical properties of sets of symbols known as Galois fields. Galois fields are represented "GF (P.sup.M)", where "P" is a prime number and "M" can be thought of as the number of digits, base "P", in each element or symbol in the field. P usually has the value 2 in digital computer and disk drive applications and, therefore, M is the number of bits in each symbol. The ECC's commonly used with the Galois Fields are Reed Solomon codes or BCH codes.
Reed Solomon and BCH encoding and decoding operations involve a plurality of Galois field multiplication operations. The Galois field multiplication operations are modulo g(x), which is the generator polynomial of the Galois field. The modulo g(x) operation, also denoted mod g(x), for g(x)=g.sub.n x.sup.n +g.sub.n-1 x.sup.n-1 + . . . +g.sub.1 x+g.sub.0 is defined as p(x) mod g(x)=r(x), where r(x) is the remainder of p(x) divided by g(x). Accordingly, EQU x.sup.i mod g(x)=x, for i<n EQU x.sup.n mod g(x)=g.sub.n-1 x.sup.n- +g.sub.n-2 x.sup.n-2 + . . . +g.sub.1 x+g.sub.0 EQU x.sup.n+1 mod g(x)=g.sub.n-1 x.sup.n-1 +g.sub.n-2 x.sup.n-2 + . . . g.sub.1 x+g.sub.0)+g.sub.n-2 x.sup.n-1 +g.sub.n-3 x.sup.n-2 + . . . +g.sub.1 x.sup.2 +g.sub.0 x EQU x.sup.n+j mod g(x)=d.sub.j,.sub.n-1 x.sup.n-1 +d.sub.j,.sub.n-2 x.sup.n-2 + . . . d.sub.j,.sub.1 x+d.sub.j,.sub.0
The conventional Galois field multiplication operation over GF(2.sup.n) involves three steps: multiplying two degree-(n-1) polynomials a(x) and b(x) together bit-by-bit to produce a degree-(2n-2) polynomial c(x); mapping the x.sup.2n-2, x.sup.2n-3, . . . x.sup.n terms of c(x) to: ##EQU1## and exclusive-OR'ing the terms of the summation to the x.sup.n-1, x.sup.n-2, . . . x.sup.0 terms of c(x). This conventional method involves, in the first step, 2n-1 bit computations to produce the degree-(2n-2) polynomial and, in the second step, a complicated mapping scheme. For example, Galois field multiplication over GF(2.sup.8), with g(x)=x.sup.8 +x.sup.4 +x.sup.3 +x.sup.2 +1 includes the relatively complicated mapping of the sequence c.sub.14, c.sub.13 . . . c.sub.8 to the sequence c.sub.11 +c.sub.12 +c.sub.13, c.sub.10 +c.sub.11 +c.sub.12, c.sub.9 +c.sub.10 +c.sub.11, c.sub.8 +c.sub.9 +c.sub.10 +c.sub.14, c.sub.8 +c.sub.9 +c.sub.11 +c.sub.12, c.sub.8 +c.sub.10 +c.sub.12 +c.sub.13, c.sub.9 +c.sub.13 c.sub.14, c.sub.8 +c.sub.12 +c.sub.13. For larger Galois fields the mapping is even more complicated.
One known prior system avoids the complicated mapping by performing sequential modulo g(x) operations. Such a system uses the results of a previous x.sup.i b(x) mod g(x) computation to determine x.sup.i+1 b(x) mod g(x)=x[x.sup.i b(x) mod g(x)]mod g(x). The iteration involves one shift and one exclusive-OR operation of two n-bit symbols. While each iteration is straight forward, the entire operation is slow, particularly for larger Galois fields, because of the number of iterations that must be performed.
Larger Galois fields, that is, fields larger than GF(2.sup.8) are being used more and more as the density of the data increases. The larger fields are necessary to produce the longer data codewords that are required to protect the data. Consequently, Galois field multiplication operations over the larger fields must be performed to both encode and decode the data codewords. What is needed is a Galois field multiplier that is less complex than the conventional Galois field multipliers, and produces the product relatively quickly. | {
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1. Field
This disclosure relates generally to semiconductor device packaging, and more specifically, to a mechanism to reduce localized stress in the area of electrical interconnects under a packaged device die.
2. Related Art
In certain types of semiconductor device packaging, semiconductor device die contacts are electrically coupled to a package substrate interconnect. Traditional methods of forming this coupling involve a solder reflow operation using solder bumps or solder-tipped metal columns formed on contacts of the semiconductor device die to contacts on the package substrate interconnect. These methods involve heating at least the contact region to temperatures sufficient to cause the solder to flow.
Issues have arisen in recent packaging development work on semiconductor die having lead-free solder bumps or solder-tipped metal columns, in which semiconductor die inter-layer dielectric delamination occurs under the bumps or metal columns, known as white bumps or ghost bumps on large die/large packages. Delamination is a particular issue for semiconductor die using low-k and ultra-low-k dielectrics (e.g., films composed of silicon, carbon, oxygen, and hydrogen—SiCOH films) that tend to be more brittle due to their increased porosity. This delamination occurs, in part, due to differences in the coefficient of thermal expansion between the semiconductor device die material and the package substrate material. As the different materials cool down subsequent to solder reflow, a high stress occurs in the interconnect region, resulting in the delamination.
It is therefore desirable to provide a mechanism for electrically coupling a semiconductor device die to a semiconductor device package substrate that avoids introduction of excessive temperature induced stresses to the semiconductor device die interconnect.
The use of the same reference symbols in different drawings indicates identical items unless otherwise noted. The figures are not necessarily drawn to scale. | {
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In a multicarrier mobile communication system, a Base Station (BS) performs downlink data transmission to User Equipments (UEs) in one or more cells. The BS needs to allocate communication resources in the time-frequency domain to each UE when the BS transmits downlink data to a specific UE since a plurality of UEs may be present in a cell and each UE does not know when and in which format data will be transmitted to the UE. The BS transmits information of such resource allocation to each UE by transmitting a control signal including the resource allocation information to the UE.
In order for each UE to transmit data packet in the uplink, the BS also needs to allocate communication resources in the time-frequency domain to each UE and to transmit control information to allow the UE to transmit data through the uplink.
When the BS allocates resources for data transmission in the uplink/downlink, for example in the OFDM system, the BS can define a small unit such as one subcarrier, a large unit such as tens of subcarriers, or a larger unit as a basic unit of the allocation.
When small allocation units such as subcarriers are used for resource allocation of the BS, resource allocation information for data transmission, which the BS transmits to each UE using a control signal, includes all information as to whether or not each subcarrier is allocated to the UE, thereby increasing the overhead. On the other hand, when larger allocation units are used, there is an advantage in that the overhead is reduced while there is a problem in that the flexibility of resource allocation is reduced since each UE cannot be allocated small resources for data transmission.
For example, let us assume that 576 subcarriers can be used for downlink data transmission in an OFDMA system with subcarrier intervals of 15 KHz in a 10 MHz system band. In this case, if a single basic resource block as a minimum unit of resource allocation is designed to include a unit time of 0.5 ms and 12 subcarriers, the total band is divided into 96 basic resource blocks every 1 ms and, when transmitting data to each UE every 1 ms, the BS must inform the UE of which one of the 96 basic resource blocks is used to transmit the data to the UE through resource allocation information such as scheduling information.
Here, in order to allow a scheduler of the BS to transmit data through any basic resource blocks to any UE under no constraints, a scheduling command for each UE must include 96-bit information individually representing the used resource blocks. Specifically, if signaling for resource allocation informs each UE whether or not a corresponding resource block has been used according to whether a specific bit is “0” or “1”, the signaling for resource allocation will require 96 bits, resulting in large overhead.
However, using a larger number of subcarriers as a base resource block unit to reduce the overhead causes problems in the flexibility of resource allocation. For example, if transmission data, which has an amount to be transmitted through 36 subcarriers for 1 ms, is generated in a transmission buffer for a UE when 72 subcarriers are set as a base resource block unit, the BS must transmit the data using a larger amount of frequency-time resources than required since a basic resource block consists of 72 subcarriers or must delay the transmission until another data to fill the basic resource block is generated for the UE.
Accordingly, there is a need to provide a resource allocation method, which can overcome these resource allocation flexibility problems and the above resource allocation information overhead problems, and a method for transmitting resource allocation information for the same. | {
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Cellular DNA undergoes double strand breakage during the course of many physiological events as well as in response to a variety of environmental insults (1, 2). Left unrepaired, such double strand breaks (DSBs) lead to mutations that may prove lethal to the organism. Therefore, these DSBs are repaired promptly via two independent pathways: i) homologous recombination ii) non-homologous end joining (1,2). The first pathway involves a series of very specific biochemical reactions catalyzed by a complex of cellular proteins (3). Due to the large number of proteins involved in this complex, it is referred to as a `recombinosome` (4). This pathway is the dominant mode of DSB repair in lower eukaryotes such as yeast (2).
The non-homologous end-joining pathway is the major route of DSB repair in higher eukaryotes (1,2). This pathway is also catalyzed by a group of cellular proteins. This group contains, in addition to hitherto unidentified factors, some well-characterized enzymes such as DNA ligases, Poly (ADP-Ribose) Polymerase [PADPRP], and DNA--dependent Protein Kinase [DNA-PK] (5,6). These enzymes have been studied in detail using lower as well as higher vertebrate systems including mammals. Both PADPRP and DNA-PK have been shown to be activated by DNA ends. Moreover, these two enzymes also bind DNA ends (5,6). While PADPRP is a single polypeptide of .about.115 kDa (7), DNA-PK exists as a complex of two subunits (8,9). The catalytic subunit [DNA-PK.sub.cs ] is composed of a single polypeptide of .about.450 kDa. It is a serine-threonine type of protein kinase that phosphorylates a variety of nuclear enzymes, transcription factors and oncogenes (9). However, DNA-PK.sub.cs by itself does not bind DNA. The non-catalytic subunit of DNA-PK is a heterodimer composed of 70 kDa and 86 kDa proteins. The non-catalytic subunit acts as a regulator of DNA-PK.sub.cs by virtue of its' ability to bind to DNA ends, thereby recruiting the catalytic subunit to the site of DSBs (8,9).
Although enzymology of DNA-PK.sub.cs has been investigated extensively (8), its biological function was identified only recently (10). Availability of the full length cDNA sequence of mammalian DNA-PK.sub.cs allowed identification of this protein as a member of the phosphotidyl inositol 3-kinase (PI kinase) gene family. While most members of this family are lipid kinases, a small number of proteins forming a subfamily specifically phosphorylate proteins. Members of this subfamily are known as PI-K related kinases and include the ATM protein, Tellp, Tor1p, Tor2p, FRAP, Rad3p, Mec1p and Mei4l (10). In addition to their structural and biochemical similarities, members of this subfamily also appear to share a common biological function. They are all involved in repair of DNA that is damaged in response to a variety of genetic, physiological or environmental events (10). Although several members of this subfamily have been cloned from animals, no known information on plant DNA-PK.sub.cs is available in the literature.
The non-catalytic subunit of DNA-PK appear to be identical to previously well characterized mammalian Ku proteins (8). The Ku complex, also a heterodimer of 70 kDa and 86 kDa proteins, was shown to be a nuclear DNA-binding autoantigen (12,13). Patients diagnosed of a variety of autoimmune diseases have been known to develop antibodies to Ku proteins (14). Further biochemical analysis has established that Ku binds with strong affinity to DNA ends, stem-loop structures, DNA bubbles, or transitions between double stranded DNA and two single strands (15). Subsequent to binding to the ends, Ku molecules can translocate along the DNA, such that three or more molecules can bind to the linear DNA fragment. Both components of Ku have a DNA dependent ATPase activity and an ATP dependent helicase activity (15). Recently, Yoo and Dynan have also demonstrated RNA binding activity of the Ku protein (16).
Recent genetic studies using rodent cell lines defective in DNA strand break repair have provided the important link between Ku protein, DNA-PK and DSB repairs during DNA replication, repair and recombination (16). Boulton & Jackson have shown that the yeast Ku70 potentiates illegitimate DNA DSB repair and serves as a barrier to error-prone DNA repair pathways (17). Studies with mutant rodent cell lines have clearly shown that Ku proteins are required for the V (D) J DNA recombination (18) and immunoglobulin isotype switching (19). Components of DNA-PK are also involved in the non-homologous end-joining pathway in telomeric length maintenance and telomere silencing (20) as well as telomere integrity (21). Ramsden & Gellert have recently observed that Ku protein stimulates DNA end joining by mammalian DNA ligases and proposed a direct role for Ku in DSB repair (22). A role for Ku protein in modulation of heat shock response (23), and hyperthermic radiosensitization (24) has also been advocated. As discussed above, recent studies have established the role of DNA-PK components in various cellular processes involving DSB. During the course of these investigations, Ku orthologues have been cloned from human (25, 26), mouse (27), Drosophila melanogaster (28), Rhipicephalus appendiculatus (29) and Caenorhabditis elegans (30). Interestingly, Ku orthologues have also been reported in Saccharomyces cerevisiae (31-33).
Control of homologous recombination or non-homologous end joining by modulating Ku provides the means to modulate the efficiency which heterologous nucleic acids are incorporated into the genomes of a target plant cell. Control of these processes has important implications in the creation of novel recombinantly engineered crops such as maize. The present invention provides this and other advantages. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
This invention relates to a recording and/or reproducing apparatus arranged to process, record and/or reproduce images and sounds.
2. Description of the Related Art
FIG. 8 shows in a block diagram a conventional digital electronic camera. Referring to FIG. 8, the digital electronic camera 800 is arranged to use a memory card 801 as a recording medium. The camera 800 includes a photo-taking lens 1, a diaphragm shutter 2 which is a shutter, but functions as a diaphragm as well, and a flash device 3. A CPU 4 is arranged to control mechanical and operation parts. A driving circuit 5 is arranged to drive each part of a mechanical system. An image sensor 6 is arranged to convert into an electrical signal a reflection light which comes from an object of shooting. A timing signal generating circuit (abbreviated to a TG circuit) 7 is arranged to generate a timing signal necessary for operating the image sensor 6. An image sensor driving circuit 8 is arranged to amplify the timing signal from the timing signal generating circuit 7 up to a level necessary for driving the image sensor 6. A preprocessing circuit 9 is provided with a CDS circuit for removing a noise from the output of the image sensor 6 and a nonlinear type amplifying circuit for amplifying the output of the image sensor 6 prior to an A/D (analog-to-digital) conversion process. Reference numeral 10 denotes an A/D converter and reference numeral 12 a buffer memory. A signal processing system control CPU 13 is arranged to control each part of a signal processing system. An operation display part 14 is arranged to make a display in aid of operation by showing the state of the camera. An externally-accessible operation part 15 is provided for operating the camera. A memory controller 802 is arranged to control the buffer memory 12. A digital signal processing circuit 803 is arranged to make the output of the image sensor 6 into a form suited for recording on the memory card 801. A memory card interface (I/F) 804 is arranged to connect the digital electronic camera 800 to the memory card 801. The conventional digital electronic camera 800 operates as described below with reference to FIG. 8.
With the operation part 15 operated by a camera operator, the digital electronic camera 800 enters into a state of performing a shooting action. The photo-taking lens 1 is controlled by the mechanical and operation part control CPU 4 and the mechanical system driving circuit 5 in accordance with the intention of the operator. At this time, the conditions of shooting, etc., are displayed at the display part 14 to inform the operator of the state of the camera 800. The luminance of the object of shooting is measured by a light measuring circuit which is not shown. An aperture value and a shutter speed of the diaphragm shutter 2 are then derived from the mechanical and operation part control CPU 4. The mechanical system driving circuit 5 drives the diaphragm shutter 2 on the basis of the control values thus derived from the CPU 4. Depending on the output of the light measuring circuit, a shot may be taken by flashing the flash device 3. When an exposure is effected in this manner, a reflection light from the object of shooting comes to fall upon the image sensor 6 via the photo-taking lens 1 and the diaphragm shutter 2. The diaphragm shutter 2 then acts to limit the quantity of the incident light upon the image sensor 6. If the image sensor 6 is an interlaced reading type CCD, the diaphragm shutter 2 is arranged to prevent an electric charge signal from being affected by the incident light. The image sensor 6 is arranged to be operated by a driving signal which is outputted from the TG circuit 7 and is amplified by the image sensor driving circuit 8. The action of the TG circuit 7 is controlled by the signal processing system control CPU 13. The output of the image sensor 6 which is driven in this manner is supplied to the preprocessing circuit 9. Upon receipt of the output of the image sensor 6, the preprocessing circuit 9 performs a CDS (correlated double sampling) process to remove a low band noise from the output of the image sensor 6 (or a pickup image signal) and a process of making the pickup image signal into a nonlinear state for the effective use of the dynamic range of the A/D converter 10. The pickup image signal thus preprocessed is converted into a digital signal by the A/D converter 10. The digital signal thus obtained is inputted to the memory controller 802. Under the control of the signal processing system control CPU 13, the memory controller 802 at first temporarily stores the digitized pickup image signal in the buffer memory 12 and then reads out the stored digital signal in order as determined by the arrangement of color filters of the image sensor 6. The digital signal thus read out is converted into a signal of a predetermined format by the digital signal processing circuit 803. The signal thus processed is recorded on the memory card 801 through the memory card interface (I/F) 804.
The conventional digital electronic camera described above, however, has the following problems.
(i) The functions of the camera are limited to picking up and recording still images and permit neither taking any motion picture nor combining with sound data. PA1 (ii) The camera has a limited data compressing method for efficient recording on the recording medium and does not permit adoption of any other method. PA1 (iii) It is difficult to combine the camera with an image pickup device and a sound input/output device into a highly advanced information processing apparatus having effective functions including, for example, OCR (optical character recognition), voice recognition, voice synthesis, translation, image recognition, image synthesis, etc.
Any attempt to overcome these problems, on the other hand, would necessitate incorporation of all these processing functions into the apparatus. Such an attempt, therefore, increases not only the size of the apparatus but also its price and would become a great demerit of the apparatus for a person not requiring such functions. | {
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In the process of drilling a wellbore, frictional forces acting against the drill pipe or other component running through the wellbore limit the maximum length or depth to which the wellbore may be drilled. Conventional methods of drilling achieve lengths of 10,000 to 15,000 feet.
Prior art solutions include mechanisms for vibrating the drill pipe during drilling in order to convert static frictional forces on the drill pipe to dynamic frictional forces between the drill pipe and the wall of the wellbore. One method of vibrating drill pipe within a wellbore includes using a valve in the drill string to create a pressure pulse in conjunction with a shock sub. The pressure pulse causes the shock sub to stretch and the drill pipe to vibrate axially, which allows the drill pipe to reach greater lengths or depths within the wellbore. Certain prior art pressure pulse generation tools use a separate power section to activate the valve. These tools, however, use elastomers that are sensitive to heat and chemicals in drilling mud. Other prior art tools use poppet valves that move up and down to open and close fluid ports. These poppet valve tools, however, are very complicated and cannot be used with drilling mud containing any kind of solids. Furthermore, conventional vibrating tools and methods provide vibration during the entire duration of drilling, i.e., from beginning of pumping drilling fluid through the drill pipe and vibration tool. The constant vibration places undue wears on the vibration tool resulting in reduce longevity. | {
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1. Field of the Invention
The invention relates to newly identified mammalian chemosensory G protein-coupled receptors, to family of such receptors, and to the genes and cDNA encoding said receptors. More particularly, the invention relates to newly identified mammalian chemosensory G protein-coupled receptors active in taste signaling, to a family of such receptors, to the genes and cDNA encoding said receptors, and to methods of using such receptors, genes, and cDNA in the analysis and discovery of taste modulators.
2. Description of the Related Art
The taste system provides sensory information about the chemical composition of the external world. Taste transduction is one of the most sophisticated forms of chemical-triggered sensation in animals. At present, the means by which taste sensations are elicited remains poorly understood. See, e.g., Margolskee, BioEssays, 15:645-50 (1993); Avenet et al., J. Membrane Biol., 112:1-8 (1989). Taste signaling is found throughout the animal kingdom, from simple metazoans to the most complex of vertebrates. Taste sensation is thought to involve distinct signaling pathways. These pathways are believed to be mediated by receptors, i.e., metabotropic or inotropic receptors. Cells which express taste receptors, when exposed to certain chemical stimuli, elicit taste sensation by depolarizing to generate an action potential, which is believed to trigger the sensation. This event is believed to trigger the release of neurotransmitters at gustatory afferent neuron synapses, thereby initiating signaling along neuronal pathways that mediate taste perception. See, e.g., Roper, Ann. Rev. Neurosci., 12:329-53 (1989).
As such, taste receptors specifically recognize molecules that elicit specific taste sensation. These molecules are also referred to herein as “tastants.” Many taste receptors belong to the 7-transmembrane receptor superfamily (Hoon et al., Cell 96:451 (1999); Adler et al., Cell 100:693 (2000)), which are also known as G protein-coupled receptors (GPCRs). Other tastes are believed to be mediated by channel proteins. G protein-coupled receptors control many physiological functions, such as endocrine function, exocrine function, heart rate, lipolysis, carbohydrate metabolism, and transmembrane signaling. The biochemical analysis and molecular cloning of a number of such receptors has revealed many basic principles regarding the function of these receptors.
For example, U.S. Pat. No. 5,691,188 describes how upon a ligand binding to a GPCR, the receptor presumably undergoes a conformational change leading to activation of the G protein. G proteins are comprised of three subunits: a guanyl nucleotide binding α subunit, a β subunit, and a γ subunit. G proteins cycle between two forms, depending on whether GDP or GTP is bound to the α subunit. When GDP is bound, the G protein exists as a heterotrimer: the Gαβγ complex. When GTP is bound, the α subunit dissociates from the heterotrimer, leaving a Gβγ complex. When a Gαβγ complex operatively associates with an activated G protein-coupled receptor in a cell membrane, the rate of exchange of GTP for bound GDP is increased and the rate of dissociation of the bound Gα subunit from the Gαβγ complex increases. The free Gα subunit and Gβγ complex are thus capable of transmitting a signal to downstream elements of a variety of signal transduction pathways. These events form the basis for a multiplicity of different cell signaling phenomena, including for example the signaling phenomena that are identified as neurological sensory perceptions such as taste and/or smell.
Mammals are believed to have five basic taste modalities: sweet, bitter, sour, salty, and umami (the taste of monosodium glutamate). See, e.g., Kawamura et al., Introduction to Umami: A Basic Taste (1987); Kinnamon et al., Ann. Rev. Physiol., 54:715-31 (1992); Lindemann, Physiol. Rev., 76:718-66 (1996); Stewart et al., Am. J. Physiol., 272:1-26(1997). Numerous physiological studies in animals have shown that taste receptor cells may selectively respond to different chemical stimuli. See, e.g., Akabas et al., Science, 242:1047-50 (1988); Gilbertson et al, J. Gen. Physiol., 100:803-24 (1992); Bernhardt et al., J. Physiol., 490:325-36 (1996); Cummings et al., J. Neurophysiol., 75:1256-63 (1996).
In mammals, taste receptor cells are assembled into taste buds that-are distributed into different papillae in the tongue epithelium. Circumvallate papillae, found at the very back of the tongue, contain hundreds to thousands of taste buds. By contrast, foliate papillae, localized to the posterior lateral edge of the tongue, contain dozens to hundreds of taste buds. Further, fungiform papillae, located at the front of the tongue, contain only a single or a few taste buds.
Each taste bud, depending on the species, contains 50-150 cells, including precursor cells, support cells, and taste receptor cells. See, e.g., Lindemann, Physiol. Rev., 76:718-66 (1996). Receptor cells are innervated at their base by afferent nerve endings that transmit information to the taste centers of the cortex through synapses in the brain stem and thalamus. Elucidating the mechanisms of taste cell signaling and information processing is important to understanding the function, regulation, and perception of the sense of taste.
Although much is known about the psychophysics and physiology of taste cell function, very little is known about the molecules and pathways that mediate its sensory signaling response. The identification and isolation of novel taste receptors and taste signaling molecules could allow for new methods of chemical and genetic modulation of taste transduction pathways. For example, the availability of receptor and channel molecules could permit the screening for high affinity agonists, antagonists, inverse agonists, and modulators of taste activity. Such taste modulating compounds could be useful in the pharmaceutical and food industries to improve the taste of a variety of consumer products, or to block undesirable tastes, e.g., in certain pharmaceuticals.
Complete or partial sequences of numerous human and other eukaryotic chemosensory receptors are currently known. See, e.g., Pilpel, Y. and Lancet, D., Protein Science, 8:969-977 (1999); Mombaerts, P., Annu. Rev. Neurosci., 22:487-50 (1999). See also, EP0867508A2, U.S. Pat. No. 5,874,243, WO 92/17585, WO 95/18140, WO 97/17444, WO 99/67282. Because of the complexity of ligand-receptor interactions, and more particularly tastant-receptor interactions, information about ligand-receptor recognition is lacking. In part, the present invention addresses the need for better understanding of the interactions between chemosensory receptors and chemical stimuli. The present invention also provides, among other things, novel chemosensory receptors, and methods for utilizing such receptors, and the genes a cDNAs encoding such receptors, to identify molecules that can be used to modulate chemosensory transduction, such as taste sensation. | {
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1. Field of the Invention
This invention relates to porous polytetrafluoroethylene (hereinafter "PTFE") materials having a unique and useful combination of high strength and coarse microstructure, and a method for producing these materials. Articles made from these materials are particularly suitable for use in the medical field.
2. Description of the Prior Art
The products of this invention derive from paste formed products of PTFE. Paste extrusion or paste forming techniques are old in the art and consist of mixing a coagulated dispersion of polytetrafluoroethylene resin with a liquid lubricant and forcing the mixture through an extrusion die or otherwise working the lubricated mixture to form a coherent shaped article. The lubricant is then removed, usually by drying, to form a porous, unsintered PTFE article having a density usually within the range of 1.4 to 1.7 gm/cc. Such densities correspond to porosities of 39% to 26%, respectively. At this stage, the article can be raised above its crystalline melt point of about 345.degree. C. to sinter it, coalescing the porous material to form a non-porous sintered article.
Alternatively, the unsintered article can be made more porous and stronger by stretching according to techniques taught in U.S. Pat. No. 3,953,566. Subsequent to stretching, the stretched article can be held restrained and heat treated above the crystalline melt point. In this instance, the article remains porous and when cooled a strong porous article of PTFE is obtained. In the discussions which follow, the term "sintering" is used interchangeably with the process step of raising the unsintered article above its crystalline melting point. U.S. Pat. No. 3,953,566 provides a method of producing all kinds of microporous stretched PTFE, such as films, tubes, rods, and continuous filaments. The articles are covered by U.S. Pat. No. 4,187,390. The microstructure of these articles consists of nodes interconnected by fibrils.
The key element of the U.S. Pat. No. 3,953,566 process is rapid stretching of PTFE. Rapid stretching allows the unsintered article to be stretched much farther than had previously been possible while at the same time making the PTFE stronger. The rapid stretching also produces a microstructure which is very fine in scale having, for example, a very small effective pore size. U.S. Pat. No. 3,962,153 describes very highly stretched products, stretch amounts exceeding 50 times the original length. The products of both the U.S. Pat. Nos. 4,187,390 and 3,962,153 patents have relatively high matrix tensile strengths. (See discussion of "matrix tensile strengths" and relation to article tensile strength and density in U.S. Pat. No. 3,953,566 at col. 3, lines 28-43.)
To compute the marix tensile strength of a porous specimen, one divides the maximum force required to break the sample by the cross sectional area of the porous sample, and then multiplies this quantity by the ratio of the density of the PTFE polymer component divided by the density of the porous specimen. The density of PTFE which has never been raised above its crystalline melt point is 2.30 gm/cc while the density of PTFE which has been sintered or raised above its crystalline melt point may range from above 2.0 gm/cc to below 2.30 gm/cc. For purposes of calculating matrix tensile strength in examples which follow, we have used a density of the PTFE polymer of 2.20 gm/cc for products which have been raised above the crystalline melt point, and a density of 2.30 gm/cc for those which have not.
When the unsintered articles are stretched at slower rates, either limited stretching occurs because the material breaks, or weak materials are obtained. These weak materials have microstructures that are coarser than articles that are stretched equivalent amounts but at faster rates of stretch. The term, "coarse," is used to indicate that the nodes are larger, the fibrils are longer, and the effective pore size is larger. Such coarse microstructures would have further utility if they were strong instead of weak. | {
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A normal ear transmits sounds as shown in FIG. 1 through the outer ear 101 to the tympanic membrane (eardrum) 102, which moves the bones of the middle ear 103 (malleus, incus, and stapes) that vibrate the oval window and round window openings of the cochlea 104. The cochlea 104 is a long narrow duct wound spirally about its axis for approximately two and a half turns. It includes an upper channel known as the scala vestibuli and a lower channel known as the scala tympani, which are connected by the cochlear duct. The cochlea 104 forms an upright spiraling cone with a center called the modiolar where the spiral ganglion cells of the acoustic nerve 113 reside. In response to received sounds transmitted by the middle ear 103, the fluid-filled cochlea 104 functions as a transducer to generate electric pulses which are transmitted to the cochlear nerve 113, and ultimately to the brain.
Hearing is impaired when there are problems in the ability to transduce external sounds into meaningful action potentials along the neural substrate of the cochlea 104. To improve impaired hearing, auditory prostheses have been developed. For example, when the impairment is related to operation of the middle ear 103, a conventional hearing aid may be used to provide acoustic-mechanical stimulation to the auditory system in the form of amplified sound. Or when the impairment is associated with the cochlea 104, a cochlear implant with an implanted stimulation electrode can electrically stimulate auditory nerve tissue with small currents delivered by multiple electrode contacts distributed along the electrode.
FIG. 1 also shows some components of a typical cochlear implant system which includes an external microphone that provides an audio signal input to an external signal processor 111 where various signal processing schemes can be implemented. The processed signal is then converted into a digital data format, such as a sequence of data frames, for transmission into the implant 108. Besides receiving the processed audio information, the implant 108 also performs additional signal processing such as error correction, pulse formation, etc., and produces a stimulation pattern (based on the extracted audio information) that is sent through an electrode lead 109 to an implanted electrode array 110. Typically, this electrode array 110 includes multiple electrodes on its surface that provide selective stimulation of the cochlea 104.
Existing cochlear implant systems need to deliver electrical power from outside the body through the skin to satisfy the power requirements of the implanted portion of the system. FIG. 1 shows a typical arrangement based on inductive coupling through the skin to transfer both the required electrical power and the processed audio information. As shown in FIG. 1, an external transmitter coil 107 (coupled to the external signal processor) is placed on the skin adjacent to a subcutaneous receiver coil in the implant 108. Often, a magnet in the external coil structure interacts with a corresponding magnet in the subcutaneous secondary coil structure. This arrangement inductively couples a radio frequency (rf) electrical signal to the receiver in the implant 108, which is able to extract from the rf signal both the audio information for the implanted portion of the system and a power component to power the implanted system.
In most prior systems, the external components generally have been held in separate housings so that the external transmitter coil 107 would not be in the same physical housing as the power source or the external signal processor. The various different physical components would generally be connected by hard wire, although some systems used wireless links between separate external components. A few systems have been proposed in which all of the external components such as an external processor and a rechargeable battery could be placed within a single housing. See U.S. Patent Publication 20080002834 (Hochmair) and U.S. Patent Publication 20070053534 (Kiratzidis), which are incorporated herein by reference.
The rechargeable batteries (e.g. Lithium-Ion batteries) for such systems have conductive band materials such as aluminum and copper which are coated with battery chemistry (e.g. graphite) and are stacked on top of each other. But when such a battery is placed within a magnetic field generated by a current-carrying coil, the conductive band materials generate undesired eddy currents. Excessive eddy currents are a significant problem because they cause decreased coupling which reduces efficiency.
U.S. Pat. No. 6,067,474 by Schulman et al. teaches a coil design in the form of a long ribbon of battery electrodes. Conductive band materials are wound in a spiral (see FIGS. 7 and 9) so that the magnetic field lines generated by a coil are parallel to the conductive band materials thereby reducing eddy currents. One drawback of this approach is that in the region of overlapping conductive band materials, adjacent cathodic (46′) and anodic (48′) bands (separated by an insulator material (50′, 52′)) act as parallel plate capacitors. Such capacitance in turn may seriously increase the impedance of the coil and thereby reduce the efficiency of data and power transmission between the external coil and the implanted coil. | {
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Conventional off-axis ink supply systems for higher volume inkjet printers usually include a set of large, replaceable ink containers connected to the printhead(s) through flexible tubes with some sort of backpressure regulation. These ink supply system components are provided separately to the printer factory where they are assembled into the printer.
The same part numbers designate the same or similar parts throughout the figures. | {
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Anti-sense oligonucleotides are being developed to treat a variety of diseases, particularly viral infections, e.g. Matsukura et al, Proc. Natl. Acad. Sci., Vol. 86, pgs. 4244-4448 (1989). An antisense oligonucleotide is a synthetic oligonucleotide of varying length, usually in the range of about 12 to 30 nucleotides, or nucleotide analogs, whose sequence is complementary to a predetermined segment of RNA, either freshly transcribed or messenger (mRNA), associated with some foreign or otherwise inappropriately expressed gene. It is believed that when an antisense oligonucleotide hybridizes to its target RNA, it either blocks translation or processing of the RNA or makes it susceptible to enzymatic degradation. One problem with this approach has been the difficulty of getting the antisense oligonucleotide to its target RNA in sufficient concentration and for sufficient duration to be effective in shutting down the synthesis of undesired proteins, e.g. viral enzymes, coat proteins, and the like. The susceptibility of the phosphodiester linkage of the oligonucleotides to nuclease digestion is believed to be an important cause of this difficulty, and has prompted the development of a variety of nucleoside oligomers linked by nuclease-resistant analogs of the natural phosphodiester bond, e.g. Miller et al, U.S. Pat. No. 4,511,713 and Ts'o U.S. Pat. No. 4,469,863 (methyl- and arylphosphonates); Miro et al, Nucleic Acids Research, Vol. 17, pgs. 8207-8219 (1989) (phosphoroselenoates); Brill et al, J. Am. Chem. Soc., Vol. 111, pg. 2321 (1989)(phosphorodithioates); and Matsukura et al, Proc. Natl. Acad. Sci., Vol. 84, pgs. 7706-7710 (1987), and Gene, Vol. 72, pgs. 343-347 (1988) (phosphorothioates).
The phosphorothioate and phosphorodithioate analogs are especially promising because they are highly nuclease-resistant, have the same charge as natural oligonucleotides, and are taken up by cells in effective amounts.
Phosphorothioates can be synthesized by automated DNA synthesizers using hydrogen phosphonate or phosphoramidite chemistries. In the former approach, the phosphonate backbone can be sulfurized in a single step off of the automated synthesizer after synthesis. This is advantageous because the phosphonate moieties are sulfurized by exposure to elemental sulfur dissolved in an organic solvent. Since the sulfur readily precipitates out of solution, the off-column sulfurization avoids costly blockages of valves and tubing of the synthesizer by sulfur precipitates. A drawback of this route of phosphorothioate synthesis is that coupling yields during chain elongation are typically lower than those obtained using phosphoramidite chemistry, Gaffney and Jones, Tett. Lett., Vol. 29, pgs. 2619-2622 (1988). The practical importance of high coupling yields is demonstrated by the synthesis of a 28-mer where a 99% coupling yield per step results in an overall yield of 76% (0.99.sup.27), whereas a 96% yield per step results in an overall yield of only 33% (0.96.sup.27).
Phosphoramidite chemistry, with coupling yields typically greater than 99%, is presently the more desirable approach to phosphorothioate and phosphorodithioate synthesis. However, the phosphite intermediates, which would be sulfurized, are unstable under the conditions of the detritylization step of the reaction cycle. Thus, the phosphite linkage must be sulfurized after each coupling step. This can be accomplished with a variety of sulfurizing agents, e.g. Matsukura et al, Gene (cited above)(elemental sulfur); lyer et al, J. Org. Chem., Vol. 55, pgs. 4693-4699 (1990)(a thiosulfonate sulfurizing agent); Hirschbein, U.S. patent application Ser. No. 07/464,182 (thiuram disulfide and polysulfide sulfurizing agents); and Stec et al, U.S. patent application Ser. No. 07/512,644 (thiophosphorus sulfurizing agents). Unfortunately, none of these agents provides 100% sulfurization. At each sulfurization step a small fraction of the phosphite precursors are oxygenated instead of sulfurized. This leads to the synthesis of a complex mixture of phosphorothioate oligonucleotides with respect to the number and distribution of oxygens along the phosphodiester backbone. The fraction of a product containing a given number of oxygens follows the binomial distribution. For example, in the synthesis of a 20-mer phosphorothioate oligonucleotide where the sulfurization yield is 99% at each step, the fraction of the product with, say, 1 and 2 oxygenations in place of sulfurizations is given by the second and third terms, respectively, of the binomial expansion of (0.99+0.01).sup.20, or (.sub.1.sup.20) (0.99).sup.19 (0.01)=0.165 and (.sub.2.sup.20)(0.99).sup.18 (0.01).sup.2 =0.016, respectively. Thus, relatively large fractions of even modestly sized phosphorothioate oligonucleotides are incompletely sulfurized and, because of physiochemical similarity of the completely and incompletely sulfurized compounds, separation and/or analysis of the two species has proven to be inconvenient, usually requiring NMR analysis, or like procedures.
In view of the desire to employ phosphorothioate and phosphorodithioate analogs of oligonucleotides as pharmaceutical compounds, it would be advantageous to have available methods for preparation and analysis of the sulfurized products that would permit separation of fully sulfurized species from partially sulfurized species and that would permit a convenient and inexpensive way of monitoring yields of completely sulfurized analogs, particularly in connection with phosphoramidite and/or phosphorthioamidite chemistries. | {
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The present invention relates to a dot line printer and in particular to a spring-charged type dot line printer having a printing heat assembly in which a plurality of printing heads are linearly arrayed.
In a prior art dot line printer having a printing head assembly in which a plurality of spring-charged type printing heads are linearly arrayed, there is provided a single impact pulse generator which generates single type of impact pulse as a printing pulse. Conventionally, the single impact pulse generator is connected to all of printing heads.
However, a problem occurs that the printing density and response frequency in the center of printing heads in the printing head assembly is different from those in the vicinity of the opposite ends of the assembly since the printing characteristics in the former is different from that in the latter due to the fact that the pulse widths of the impact pulses are identical.
In order to overcome the afore-mentioned problem, the characteristics of the printing heads has been made uniform by providing magnetic members which change the magnetic circuit structures in the vicinity of opposite ends or by adjusting the printing springs. There is a problem in that the number of steps for adjusting the printing quality uniform is large.
It is an object of the present invention to provide a dot line printer which is capable of making the characteristics of the printing heads uniform and of remarkably reducing the number of steps of adjustment for the uniform printing quality.
In a first aspect of the present invention, there is provided a dot line printer having a printing head assembly including a plurality of printing heads which are linearly arrayed, is wherein said dot line printer comprises a plurality of impact pulse generators for generating impact pulses to be applied to said printing heads; and a plurality of drive circuits, each of which is electrically connected to corresponding said impact pulse generator and to corresponding group of divided printing heads for controlling the driving of the printing heads in response to the impact pulses generated in said impact pulse generators.
In a second aspect of the present invention, each of said drive circuits is electrically connected to a pair of two groups among grouped printing heads, the two groups being equally spaced from a central head in the printing head assembly on the both sides thereof.
In a third aspect of the present invention, the dot printer comprises two impact pulse generators and two drive circuits, the drive circuit corresponding to one of the impact pulse generator is electrically connected to one pair of two groups of printing heads which are in the vicinity of the opposite side ends of said printing head assembly, and the drive circuit corresponding to the other impact pulse generator is electrically connected to a group of the rest of the printing heads disposed in the middle position of said printing head assembly.
In the dot line printer, it is preferred that the impact pulse generated by said impact pulse generator is preset so that it has a different pulse width for different impact pulse generator.
In the dot line printer, it is preferred that the impact pulse is applied to the printing heads disposed in the vicinity of the opposite side ends of the printing head assembly has a pulse width which is shorter than that applied to the rest of the printing heads. | {
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The Neurotrophin Family
Neurotrophins are dimeric peptide hormones. The first member of the neurotrophin family to be discovered was nerve growth factor (NGF), which plays an important role in processes such as the development of sensory and sympathetic neurons of the peripheral nervous system (Levi-Montalcini, R. and Angeleeti, P. U, Physiol. Rev. 48, 534-569 (1968)). The next member of the neurotrophin family to be isolated was brain-derived neurotrophic factor (BDNF), also referred to as neurotrophin-2 (NT-2), the sequence of which was published by Leibrock, J. et al. in 1989 (Nature 341, 149-152). In 1990 several groups identified a neurotrophic factor originally called neuronal factor (NF), now referred to as neurotrophin-3 (NT-3) (Ernfors et al., Proc. Natl. Acad. Sci. USA 87, 5454-5458 (1990); Hohn et al., Nature 344, 339; Maisonpierre et al., Science 247, 1446; Rosenthal et al., Neuron 4, 767; Jones and Reichardt, Proc. Natl. Acad. Sci. USA 87, 8060-8064; Kaisho et al., FEBS Lett. 266, 187). Neurotrophins-4 and -5 were then added to the family (Neuron 6, 845-858 (1991); Berkmeier, L. R. et al., Neuron 7, 857-866 (1991); Ip et al., Proc. Natl. Acad. Sci. USA 89, 3060-3064 (1992)).
Receptors for the Neurotrophin Family
In a similar way to other polypeptide growth factors, neurotrophins affect their target cells through interactions with cell surface receptors. According to current knowledge, neurotrophins bind to two discrete receptor types which can be distinguished pharmacologically: the Trk and p75NTR neurotrophin receptors. p75NTR is a member of the Fas/tumour necrosis factor (TNF) receptor family, and can interact with all the mammalian members of the neurotrophin family with equal affinities (Rodriguez-Tebar et al. 1990, Neuron 4:487-492; Barker and Murphy, 1992, Mol. Cell. Biochem. 100:1-15). Cells expressing TrkA, a tyrosine kinase receptor originally identified as a human oncogene (Mltin-Zanca et al, Nature 319:743-748) bind solely to NGF and exhibit significantly slower dissociation kinetics (Jing et al. 1992, Neurol. 9:1067-1079; Loeb and Greene, 1993, Neuroscience 13:2919-2929). BDNF binds the TrkB receptor only, but NT-3 can bind all three Trk (A, B and C) receptors, with a preference for TrkC. NT-4/5 can bind both TrkA and TrkB (Ip et al. PNAS 89:3060-3064; Klein et al. Neuron 9:947-956). NT-7 does not interact with TrkB or TrkC but can however induce tyrosine phosphorylation of TrkA, indicating a similar receptor specificity as NGF (Nilsson et al., FEBS Lett (1998) March 13; 424 (3):285-90). Recombinant purified NT-6 also has a spectrum of actions similar to NGF but with a lower potency (Gott et al., Nature (1994) November 17; 372 (6503):266-9).
The Neurotrophin Family: Precursor Proteins
The biology of the neurotrophin family is complex: the neurotrophins are synthesised intracellularly as 30-35 kDa precursor proteins, containing a signal peptide and glycosylation sites. During processing precursor proteins are also cleaved at a di-basic cleavage site by the calcium-dependent serine protease furin and other members of the prohormone convertase family, within the Golgi apparatus. The N-terminal part of this cleavage is the mature neurotrophin of 118-120 amino acids and a biologically active 12-14 kDa C-terminal product (Seidah et al, Biochem. J. (1996) 314:951-960).
Clinically Relevant Roles of the Neurotrophin Family
Neurotrophins are of clinical interest as they play an important role in neuronal cell survival and differentiation (Thoenen 1991, Trends Neurosci. 14: 165-170; Raffioni et al. 1991, Ann. Rev. Biochem. 62:823-850; Chao, 1992, Neuron 9:583-593; Barbacid 1993, Oncogene 8:2033-2042). Trk receptors transmit signals promoting neuronal survival, whereas p75NTR can induce neuronal apoptosis as well as neuronal survival depending on any co-expression of TrkA (Miller et al., Cell. Mol. Life Sci. 58:1045-1053 (2001)). Certainly, it has been demonstrated that activation of TrkA receptors can negate the proapoptotic effect of p75NTR (Yoon et al., J. Neurosci. (1998) 18:3273-3281).
It is probable that the propeptides of neurotrophins play important biological roles: at least one neurotrophin precursor protein (proNGF) and its proteolytically processed and mature counterpart (NGF) product differentially activate pro- and anti-apoptotic cellular responses through preferential activation of p75NTR and TrK receptors, respectively—pro-NGF having enhanced affinity for p75NTR receptors and a reduced affinity for Trk receptors relative to the mature forms of NGF. Indeed, it has been demonstrated that pro-NGF induces p75NTR-dependent apoptosis in cultured neurons with minimal activation of TrkA-mediated differentiation or survival (Lee et al., Science (2001), 294:1945-1948).
Furthermore, neurotrophins are of clinical interest as it is known that both up-regulation of neurotrophins and increased p75NTR expression occur under pathological and inflammatory conditions, especially after nerve injury and damage to the vascular system. Indeed, Soilu-Hanninen et al. have demonstrated that the pro-apoptotic functions of p75NTR are directly implicated in injury-induced apoptosis (Soilu-Hanninen et al., J. Neurosci. 19:4824-4838 (1999)). Recently, it was also demonstrated that proNGF induces p75 mediated death of oligodendrocytes following spinal cord injury (Beatty et al., Neuron (2002), vol. 36, pp. 375-386).
It has been hypothesized that the lack of neurotrophic factors is responsible for the degeneration of selective neuronal populations as it occurs in Parkinson's disease, Alzheimer's disease and amyotrophic lateral sclerosis, and that application of corresponding neurotrophic factor might prevent neuronal degeneration [Appel, S. H., “A unifying hypothesis for the cause of amyotrophic lateral sclerosis, parkinsonism, and Alzheimer's disease,” Ann. Neurol. 10:499-505 (1981)]. In particular, as NGF is a trophic factor for the population of basal forebrain cholinergic neurons which degenerates in Alzheimer's disease, it has been speculated that NGF may be useful in the treatment of this disease.
Another reason for interest in targeting neurotrophin pathways for therapy is that studies have provided supporting evidence for the involvement of neurotrophins in depression and antidepressant action (Duman et al. Arch Gen Psychiatry (1997) 54:597-606); for instance infusion of BDNF into the hippocampus has produced an antidepressant effect in two behavioural models of depression (Shirayama et al. (2002), J Neurosci 22(8): 3251-3261).
The Vps10p-Domain Receptor Family
Sortilin (or NTR-3 or GP95) is a type I membrane receptor expressed in a number of tissues, including the brain, spinal cord, testis and skeletal muscle (Petersen et al., J. Biol. Chem., 272:3599-3605 (1997); Herman-Borgmeyer et al., Mol. Brain Res., 65:216-219 (1999)). Sortilin belongs to a family of receptors comprising Sortilin, SorLA (Jacobsen et al, J. Biol. Chem., 271:31379-31383 (1996)), SorCS1, SorCS2 and SorCS3. All the receptors in this family share the structural feature of an approximately 600-amino acid N-terminal domain with a strong resemblance to each of the two domains which constitute the luminal portion of the yeast sorting receptor Vps10p (Marcusson, E. G., et al., Cell, 77:579-586 (1994)). The Vps10p-domain comprises a C-terminal segment containing 10 conserved cysteines and an N-terminal propeptide of 40-80 amino acids.
In Sortilin, the propeptide exhibits high affinity binding to the fully processed receptor. Prevention of propeptide cleavage essentially inhibits ligand binding to Sortilin, indicating that the propeptide sterically hinders ligands from gaining access to their binding sites on the receptor (Petersen et al., EMBO J., 18:595-604, 1999).
Some progress has been made as to an understanding of the role of this family: there is evidence suggesting that Sortilin at least contains YXXφ and dileucine motifs, conforming to potent signals for Golgi-endosome sorting (Nielsen et al., EMBO 20(9):2180-2190). It is probable that the other members of the family may also fulfil a similar “sorting” function, not least because they all exhibit homology to Vsp10p, the sorting receptor for carboxypeptidase Y (CPY) in yeast. Only a small proportion of Sortilin receptors are present on the cell surface (Mazella et al. J. Biol. Chem. (1998) 273, 26273-26276; Morris et al. J. Biol. Chem. (1998) 273:3582-3587), although expression on the surface membrane can be upregulated by stimuli including insulin in 3T3-L1 adipocytes (Morris et al. J. Biol. Chem. (1998) 273:3582-3587) and neurotensin in embryonic neurons (Chabry et al., J. Biol. Chem. (1993), 286:17138-17144).
Modulating Neurotrophin Activity: The Current State of the Art
Certainly, current understanding of the biological roles of neurotrophins makes the neurotrophin family an attractive target for therapeutic intervention, and some methods for modulation of neurotrophin activity are known: 1) U.S. Pat. No. 6,417,159 discloses a method for enhancing the effect of a neurotrophin with analogues of p75NTR367-379. 2) U.S. Pat. No. 6,300,327 describes compositions and methods for potentiation of neurotrophin activity. 3) U.S. Pat. No. 6,291,247 discloses methods of screening for factors that disrupt neurotrophin conformation and reduce neurotrophin biological activity. 4) U.S. Pat. No. 5,516,772 describes K-252 derivatives which enhance neurotrophin-induced activity. | {
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1. Field of the Invention
The present invention relates to an evaporated fuel treatment apparatus which has a canister for adsorbing an evaporated fuel produced in a fuel tank and which treats the evaporated fuel and relates to a control method for a control valve provided at a communication path (a vapor path) between the fuel tank and the canister of the evaporated fuel treatment apparatus, and more particularly, relates to a method of detecting a failure in the control valve.
2. Description of the Related Art
Conventional evaporated fuel treatment apparatuses cause a canister to adsorb an evaporated fuel in order to reduce the pressure in a fuel tank, thereby preventing the evaporated fuel produced in the fuel tank from being released to the atmosphere at the time of fuel charging (see, for example, JP 2001-140705A).
JP 2001-140705A discloses an evaporated gas suppressing apparatus which has a control valve provided at a communication path between a fuel tank of a vehicle such as an automobile and a canister for adsorbing an evaporated fuel (a vapor) produced in the fuel tank, opens the control valve in a condition in which the pressure inside the fuel tank becomes higher than a predetermined pressure in a status of fueling and while the vehicle is running, and closes the control valve while the vehicle is at rest.
According to the conventional evaporated fuel treatment apparatuses, the control valve is provided at a vapor path between the fuel tank and the canister, the control valve is opened prior to fuel charging in order to allow the canister to adsorb the evaporated fuel in the fuel tank through the control valve, thereby reducing the pressure inside the fuel tank. Reduction of the pressure prevents the evaporated fuel from being released to the atmosphere during fueling.
According to the conventional evaporated fuel treatment apparatuses, the canister becomes able to adsorb the evaporated fuel upon opening of the control valve. When a driver opens a filler cap after the pressure difference between the pressure inside the fuel tank and the atmospheric pressure becomes equal to or smaller than a predetermined pressure difference, it is possible to prevent the evaporated fuel from being released to the atmosphere. At this time, it is necessary for the driver to wait to open the filler cap until the pressure difference between the pressure inside the fuel tank and the atmospheric pressure becomes equal to or smaller than a predetermined pressure difference. It is desirable that the waiting time for opening the filler cap should be short to such an extent that the driver does not feel that the driver is forced to wait.
In the meantime, vehicles like plug-in hybrid vehicles that do not run an engine for a long time normally close the control valve so that the evaporated fuel from the fuel tank is not adsorbed by the canister. When the control valve is kept closed for a long time, the control valve may be seized because of a gum element produced when a resin part of the control valve is dissolved by a liquid.
Accordingly, an opening/closing operation of the control valve can be considered in the method disclosed in JP 2001-140705A in order to detect a seizing failure of the control valve. However, an opening/closing operation of the control valve causes the canister to adsorb the evaporated fuel, so that in the case of a vehicle which does not run the engine for a long time like a plug-in hybrid vehicle, such a vehicle needs a canister with a further large capacity. | {
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This invention relates to several new pyruvate compounds and methods of treating (i) ischemia in mammalian hearts, lungs, veins, arteries and other organs or tissues, (ii) accelerating ethanol oxidation/preventing acute toxic effects of ethanol on the liver, and (iii) other recognized uses of pyruvates including, but not limited to, treating of secondary effects of diabetes, lowering of cholesterol and lipid levels, as a nutrition source which can provide as much as 100% of caloric requirements and to treat injured organs requiring a readily accessible energy source. | {
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The dishwasher sprays detergent and washing water to dishes, to wash dishes automatically.
The dishwasher is provided with at least one rack in a tub for placing dishes thereon, a sump for holding washing water, and at least one spray unit for spraying washing water to the dishes.
In the related art dishwasher, the washing water is pumped from the sump to the spray unit, lead to a spray arm along a washing water pipe, and sprayed to the dishes.
The washing water washed the dishes is recovered to the sump, and supplied to the spray unit again for spraying to the dishes.
Such a repetitive use of the washing water leads to increase foreign matters in the washing water, gradually.
According to this, washing performance is impaired, and the foreign matter is liable to block a filter at the sump. If the filter is blocked, an excessive pressure become to exert to the filter, to result in deformation of the filter. | {
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The present invention relates to a powered handpiece for driving surgical blades. More particularly, it relates to a liquid cooled, powered surgical handpiece for use in driving a surgical blade assembly, such as a surgical drill.
Powered handpieces are commonly used in many medical specialties to drive surgical blades for performing various diverse cutting functions including resection, dissection, debridement, shaving, drilling, pulverizing, and shaping of anatomical tissue. In the areas of ENT/head/neck surgery, powered or motorized handpieces and systems are commonly connected to a surgical cutting instrument including an outer tubular member forming a cutting window at a distal end thereof, and an inner blade member coaxially disposed within the outer tubular member. The inner blade assembly terminates at a distal cutting tip. With this configuration, the powered handpiece rotates and/or oscillates the inner blade member relative to the outer tubular member so as to cause the distal cutting tip to perform a desired cutting operation. Alternatively, a more conventional micro-drill bit having a cutting tip can also be connected to, and be driven by, the powered handpiece. Regardless, because the cutting procedures associated with ENT/head/neck surgery are highly delicate, yet require numerous cutting motions or rotations by the cutting tip to complete the procedure, the powered handpiece greatly decreases procedure time requirements and the physical drain on the surgeon.
Undoubtedly, surgical powered handpieces used in combination with micro-cutting instruments are highly beneficial. As with any motor, however, operation of a powered handpiece generates heat. This is especially true for ENT/head/neck procedures where the motor associated with the surgical handpiece is required to operate at highly elevated speeds. Because the surgeon directly handles the powered handpiece, over time the generated heat can cause distinct hand discomfort. This is especially true during prolonged procedures. Obviously, any distractions may negatively affect the surgeon""s performance.
Powered surgical handpieces continue to be highly useful with surgical micro-cutting instruments, especially bone drilling instruments. However, the heat generated by the powered handpiece can lead to user discomfort and may limit usefulness of the device. Therefore, a need exists for a powered surgical handpiece incorporating a cooling system.
One aspect of the present invention provides a powered surgical handpiece for use with a micro-cutting instrument, especially a bone-drilling device useful for ENT/head/neck procedures. The powered surgical handpiece includes a motor contained within a housing. The housing includes a motor enclosure surrounding the motor and a sleeve placed about the motor enclosure. At least a portion of the sleeve has an inner diameter greater than an outer diameter of a corresponding portion of the motor enclosure, such that the housing defines an internal gap or passage. Finally, the sleeve forms inlet and outlet ports that are fluidly connected to the internal passage. During use, a cooling fluid, such as de-ionized water or saline, is forced into the internal passage via the inlet port. The motor is sealed relative to the cooling fluid by the motor enclosure. Thus, the cooling fluid does not directly contact the motor, but instead serves as a heat exchange medium through which heat generated by the motor is thermally transferred to the cooling fluid via the motor enclosure. The now heated fluid exits the housing at the outlet port. As a result of the thermal transfer of heat from the motor to the cooling fluid, and the subsequent evacuation of the now-heated fluid away from the handpiece, heat transfer to an outer surface of the housing, otherwise handled by the surgeon, is minimized. In an alternative embodiment, the housing is configured to define a serpentined or specifically routed internal fluid path to optimize heat transfer. | {
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Speeding up of a rotating polygonal mirror, thereby speeding up of photo scanning is needed to realize a high-speed laser printer. Furthermore, in an optical modulation type laser printer performing an optical modulation in response to data to be printed, a high-speed modulation is needed to a high-speed laser printer.
A laser printer using a multi-beam is an effective means to a high-speed laser printer because it can reduce a rotational speed of a rotating polygonal mirror and an optical modulation speed by the number of beams in the multi-beam. For the multi-beam type laser printer to realize more high-speed printing, it is necessary to increase the number of beams in the multi-beam.
FIG. 3 shows a first example of a laser printer using a plurality of semiconductor lasers, particularly an optical system thereof. FIG. 7 shows a sectional view of an optical fiber array in a multi-beam generating section.
In FIG. 3, a semiconductor laser module 1 comprises a plurality of semiconductor lasers 2 and optical fibers 3 for leading the respective laser beam from semiconductor lasers 2. A plurality of optical fibers 3 are aligned in a row at an optical fiber array unit 4.
As shown in FIG. 7, the optical fiber array unit 4 is configured such that the optical fibers 3 whose sheath has been removed, are held in V-shaped grooves 11 formed by applying anisotropic etching to Si crystal, while being pressed against the V-shaped grooves 11 with a glass plate 12 and being fixed with an adhesive 13.
Each optical fiber 3 comprises a clad portion 31 and a core portion 32, and light propagates via the core portion 32. An outer diameter of the clad portion is generally about 125 μm and hence the distance between adjacent core portions is 125 μm even when the optical fibers are aligned in nearness layout to each other.
In the case of an optical system shown in FIG. 3 wherein a multi-beam having the above beam distance is used, since each beam distance in the multi-beam is comparatively large, if the number of beams in the multi-beam increases, the beams at both sides of the optical fiber layout largely deviate from an optical axis of the optical system. Accordingly, deterioration of aberration characteristics of optical system components may be caused.
For the reason, when using the lenses 6 and 8 in FIG. 3 for the multi-beam laser printer, it becomes necessary to use lenses with a high degree of accuracy to maintain good aberration characteristics even when the beams deviate largely from the optical axis in comparison with the case of using only one beam.
Consequently, it is impossible to increase the number of beams in a multi-beam and high speed printing is limited.
In a second example of an optical system in a laser printer using a multi-beam, a method of using a semiconductor laser array as a multi-beam generating device as shown in FIG. 5 is also possible. However, pitch narrowing is limited due to the problems such as thermal crosstalk, droop, and the like, and the same problem as the first example occurs.
As a method for solving such problems, an optical recording device shown in FIG. 4 is proposed as follows. In the optical recording device, an optical waveguide device 5 is connected to an output end of an optical fiber array 4 in which optical fibers are aligned in nearness layout to each other; and a narrow-pitched multi-beam emitted from the optical waveguide device is scanned on a photosensitive material 9 in batch. This method is disclosed in Japanese Patent Laid-Open Publication No. 11-271652.
Additionally, another recording device shown in FIG. 6 is proposed as follows. In the optical recording device, an optical waveguide device 5 is connected to an output end of a semiconductor laser array 36. Thus, using a narrow-pitched multi-beam emitted from the optical waveguide device 5 is also possible.
In the above-mentioned prior arts using the optical waveguide device, when pitch conversion of the multi-beam is applied by using a downsized optical waveguide device under a trend where the number of beams in a multi-beam increases, it is necessary to increase a curvature of a waveguide and thereby loss in the optical waveguide device may be caused.
In order to realize a curved waveguide of low loss even with a small curvature radius, it is necessary to increase a difference in refractive index between a core layer and a clad layer and narrow a waveguide width.
However, merely increasing the difference in refractive index between the core layer and the clad layer and narrowing the waveguide width, the loss of connection between the optical waveguide device and optical fibers or a semiconductor laser array undesirably increases. Accordingly, even if bend loss in an optical waveguide device can be reduced, that may not result in the improvement of the optical utilization efficiency of the whole multi-beam light source section in some cases.
A method for solving such problems is described in Paper No. C-3-148, Electronics 1, the Proceedings of the General Convention of the Institute of Electronics, Information and Communication Engineers published in 1998, or in Japanese Patent Laid-Open Publication No. 2000-66048.
The above two documents disclose the following optical waveguide device. The optical waveguide device is configured such that: the difference in refractive index between a waveguide and an over-clad layer is increased only in a curved area of the optical waveguide device to narrow a waveguide width; on the other hand, the difference in refractive index between the waveguide and the over-clad layer are reduce at the optical joint with optical fibers and the like to widen the waveguide width.
However, when using violet semiconductor lasers having a wavelength of 380 to 460 nm in a plurality of single mode optical fibers for leading a multi-beam to an optical waveguide device, it is necessary to increase an allowance of axial deviation at the time when a semiconductor laser beam enters an optical fiber core portion at a semiconductor laser module 1. For the reason, it is needed to reduce the difference in refractive index between a core and a clad, and form a structure in the vicinity of the cutoff of a TEM01 or TEM10 mode where the core diameter is increased.
Additionally, in order to increase the allowance of axial deviation between an optical fiber and the optical fiber joint of the optical waveguide device, it is needed to reduce the difference in refractive index therebetween and increase the core diameter.
Further, in the case of connecting a semiconductor laser array to an optical waveguide device too, in order to increase the allowance of their axial deviation, it is needed to connect a semiconductor laser array having a large outgoing beam diameter like a surface-emitting semiconductor laser array to an optical waveguide device having a large core diameter.
Furthermore, when reducing the difference in refractive index and increasing the core diameter also at the emitting section of an optical waveguide device, it is possible to generate a small pitch multi-beam in rows of beams in relation to a beam diameter in the multi-beam, namely to generate a multi-beam where beams are aligned in a very dense row.
As a result, the influence of aberration in an optical system is suppressed even in the case of a large number of beams and high quality optical recording can be obtained at a high speed.
However, when a multi-beam is subjected to pitch conversion and narrow-pitched in the state of a small refractive index difference and an increased core diameter, a bend loss increases in a curved area in the optical waveguide device.
Further, as shown in FIG. 12, when a waveguide width 19 is narrowed in the curved area in the optical waveguide device and the difference in refractive index between a waveguide 26 and an over-clad layer 27 is increased, a multimode is formed in the vertical direction since a waveguide thickness 20 is not changed and it becomes necessary to convert the beams into a single mode again at an emitting section and thereby loss increases.
An object of the present invention is, even when using violet semiconductor lasers as the light sources, to provide a multi-beam generating device capable of improving optical utilization efficiency at a multi-beam generating section, and to provide an optical recording device using a multi-beam emitted from the multi-beam generating device. The improvement of optical utilization efficiency at a multi-beam generating section is realized by reducing bend loss in an optical waveguide device while the coupling efficiency between optical fibers and the optical waveguide device or between a semiconductor laser array and the optical waveguide device is maintained at a high level.
Further, another object of the present invention is, even when using a large number of beams, to provide a multi-beam generating device to emit a multi-beam from an optical waveguide device that is hardly susceptible to the aberration in an optical system, and to provide an optical recording device realizing high quality optical recording at a high speed using a multi-beam emitted from the multi-beam generating device. The optical waveguide device hardly susceptible to the aberration, is realized by generating a multi-beam having a small pitch multi-beam in relation to the beam diameter in the multi-beam, namely a multi-beam where beams are aligned in a very dense state. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The present invention relates to the field of Micro Electromechanical system (MEMS) devices. It relates to electrostatic MEMS devices as variable capacitor devices and a method for producing them.
2. Description of the Related Technology
Different electrostatic actuators are known.
Comb-drive structures as an electrostatic actuator are known [Sterken T. et al., An electret-based electrostatic micro-generator, Proceedings of Transducers, The 12th International Conference on Solid State Sensors, Actuators and Microsystems, 8-12 Jun. 2003, Boston, USA, IEEE 2003, p. 1291-1294.]. This type of devices requires thick films or armatures and is therefore often realized by bulk processing, i.e. patterning the bulk of the substrate and using itself as a moving part of the device. Upon application of a bias voltage between the electrodes (fingers), the sets of inter-digitated fingers, shown e.g. in FIG. 1, shift into each other. The movement uses the single degree of freedom available to the system, i.e. the direction of the fingers; in other words the devices move in-plane.
Parallel-plate capacitors as an electrostatic actuator are also known [X. Rottenberg et al., RF-MEMS technology platform for agile mobile and satellite communications, Proc. of the 36th European Microwave Conf., pp. 1723-1726, September 2006]. This type of devices is often preferred for on-chip actuators as they only require in principle a few additional thin-film processing steps. This type of structures is indeed produced by a typical 4-mask process flow realized on top of a dielectric (insulated) substrate. Upon actuation, the movable plate or electrode gets nearer to the fixed, bottom electrode one; the device moves out-of-plane as shown e.g. in FIG. 2, whereby the movable electrode approaches the bottom electrode. The electrodes remain in different planes.
Examples of electrostatic devices (sensors and actuators) are RF-MEMS switches, switchable capacitors, tilting mirrors, power scavengers, accelerometers . . . etc. These prior art devices have the problem that integration of a 4-masks process in/or above another process is rather difficult. Moreover the dielectric layer is typically sensitive to various charging mechanisms. The release process also has a strong impact on the dielectric properties. Often malfunction of clamped-free devices occurs due to the stress-gradient in the armature.
A three-dimensional variable capacitor is described in US-patent 2005/6906905. The electrodes of the capacitor are formed in an interdigitated manner with movable MEMS comb drive electrode beams. Control or actuation electrodes on the beams drive their motion either individually or all in unison, leading to changes in the capacitance. The structure of this variable capacitor is very complex.
It is desirable to provide a variable capacitor which shows a less complex structure and which is as a result easier to manufacture.
It is further desirable to provide a simple method for producing a variable capacitor. | {
"pile_set_name": "USPTO Backgrounds"
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The present invention relates to a device for mechanically cleaning wire rod to be used in processes for the production of drawn metal wires.
xe2x80x9cWire rodxe2x80x9d is used to refer to a semi-finished metallurgical product which is long and has a round cross-section and which, by means of gradual reduction of its cross-section during the technological process known as drawing, is reduced into the form of a wire.
The wire rod is hot-manufactured and is normally covered with oxides, hydroxides and calamine which must be removed before starting the actual drawing operation. If this operation were not carried out, poor quality wires would be obtained, the dies in which drawing is performed would be subject to rapid wear and there would be a significant restriction in the speed of the entire production process. The known operating methods for preparing wire rod for drawing are based on the use of chemical processes or, alternatively, mechanical processes. Although the use of chemical processes is able to ensure a higher level of cleaning quality, it nevertheless results in increased management and plant running costs and, in particular, creates serious problems with regard to environmental pollution. The use of mechanical processes is nowadays preferable because, although it results in an inferior cleaning quality of the wire rod, it involves lower plant management and operating costs and is less damaging for the environment.
Devices for mechanically cleaning wire rod, involving the use of a press comprising gripping jaws which support steel wool or another type of abrasive material wound around the wire rod, pressing it at the same time against the wire rod, are known and form the subject of previous patents in the name of the same Applicant. As the wire rod advances between the jaws, the steel wool removes the particles of oxide which cover the metal, but is not drawn along by the wire rod because the jaws retain it constantly, compensating for any wear with a gradual reduction in the space available therefor.
It is also useful, during mechanical cleaning, to prepare the surface of the wire rod with removal of metal particles using steel wool, in order to favour the subsequent operation consisting in fixing of a powdery lubricant. It is useful, however, to be able to modify, as required, the propensity of the wire rod to retain the lubricant depending on variable parameters, such as the chemical composition of the wire rod, the conditions for supplying of the semi-finished product, the type of lubricant and the drawing speed; and in particular it may be advantageous to maximize this propensity by increasing the length of the incisions formed on the surface of the wire rod, without modifying the longitudinal extension.
These further objects have been achieved with a device in which the jaws which grip the steel wool against the wire rod are able to rotate, at a variable speed, around the wire rod, forming helical grooves in the surface of the latter. Given a constant speed of feeding of the wire rod, the grooves have a spacing which is inversely proportional to the speed of rotation of the jaws, adjustment of which may therefore allow effective control over the propensity of the wire rod to retain the lubricant. The use of this device has, however, revealed certain drawbacks which are difficult to eliminate: in particular, the monolithic structure of the jaws results in an irregular contact surface with the steel wool which is formed, on the other hand, of loose material of a non-uniform nature, resulting in efficient pressure only in certain zones along the axis of the device. The need for mechanical balancing results in the use of jaw synchronization means located halfway along the axial extension of the jaws, with partial obstruction of the zone where the steel wool exerts its abrasive action on the wire rod. Finally, rotation of the jaws may result in twisting of the wire rod, resulting in compromises with negative effects in terms of operation of the device: for example, a necessary reduction in the speed of rotation or smaller dimensions of the device in the axial direction, i.e. parallel to the direction of feeding of the wire rod.
The object of the present invention is therefore to eliminate the drawbacks mentioned above. In accordance with the invention, this object is achieved by means of a device for mechanically cleaning wire rod, of the type indicated in the preamble of claim 1, in which the jaws which grip the steel wool, or other abrasive material, against the wire rod are supported by operating members consisting of adjacent and independent pairs of floating plates.
The main advantage obtained by means of the present invention consists in the fact that a uniform distribution, in the axial direction, of the pressure exerted by the jaws on the abrasive material is achieved and therefore the efficiency of the device is optimized. Moreover, the mechanical balancing, which is independent for each pair of plates, is advantageously achieved without obstructing the zone where the steel wool rubs against the wire rod; the structure of the plates may be lightened since their mutual independence replaces the considerable inertia of the monolithic device; as a result of the modularity of the jaws formed in this way, it is also possible to provide devices with dimensions satisfying the most widely varying requirements, keeping to a minimum the warehouse supplies, formed by plates which are all identical to each other. Finally, an important advantage consists in the fact that, for the same dimensions compared to the previously known device, the jaws may be formed by two sets of pairs of rotating plates which rotate in opposite directions to each other: in this way, twisting of the wire rod is compensated for and the surface of the latter has, etched on it, a double helix which will ensure a better propensity for retaining the lubricant and therefore an improved cleaning quality. | {
"pile_set_name": "USPTO Backgrounds"
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Field of the Invention
The invention relates to a touch apparatus, and particularly relates to a touch display apparatus.
Description of Related Art
Touch display apparatuses are generally divided into resistive, capacitive, optical, acoustic and electromagnetic touch display apparatuses according to different touch sensing methods. Since the capacitive touch display apparatus has advantages of fast response speed, high reliability, high durability, etc., it has been widely used in various electronic products. According to different structures and manufacturing methods, the capacitive touch display apparatuses are roughly divided into an added-on type and an on-cell/in-cell type capacitive touch display apparatuses. However, regardless of the added-on type, the on-cell or the in-cell type, a plurality of touch electrodes of the capacitive touch display apparatus is overlapped with a plurality of pixel regions of a display panel. Since the touch electrodes and the display panel all have periodically arranged components and are overlapped to each other, the touch display apparatus is easy to produce a moiré pattern, which is of no avail for a visual effect of the touch display apparatus. | {
"pile_set_name": "USPTO Backgrounds"
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In a mobile wireless device, a wide band and high gain characteristics must be ensured by stabilizing an antenna current flowing through housings and circuit boards in accordance with the wavelength.
In a foldable mobile wireless device, antenna current flows in a coaxial cable and the like that electrically connects circuit boards provided inside two housings.
Since the coaxial cable and the like passes via a hinge for joining the two housings, it is difficult to ensure a large ground-contact area. This leads to a problem that the coaxial cable and the like functions as a coil at high frequencies. Furthermore, since the antenna current and its return current flow in the coil cable and the like, there is also a problem of reverse-phase cancellation of the antenna current.
To avoid such problems, as disclosed in Patent document 1, conductors connected to a reference potential section (ground) of each circuit board are provided at base ends of two housings (hinge vicinity), and antenna current is flowed through them by capacitance-coupling them at high frequency, thereby avoiding cancellation and the like of antenna current.
[Patent document 1] Japanese Unexamined Patent Application, First Publication No. 2006-54843 | {
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The present invention relates to a process for making thermoset polymer resin laminates and to products characterized by excellent solderability and solvent resistance which are prepared using such process. More particularly, the present invention relates to thermoset compositions comprising blends of polyphenylene ethers and certain multifunctional acrylics, e.g., triallylcyanurate, diallyl maleate, and methacryloyl chloride, which offer processing, cost, and/or performance advantages over the existing polyphenylene oxide/epoxy state-of-the-art, particularly in consumer electronic laminate applications.
Metal-clad boards, particularly such boards for use in fabricating printed circuits, are well-known in the art. The simplest of such boards generally comprises a resinous plastic (polymeric) substrate to which is bonded at least one thin sheet of an electrically conductive material, preferably copper. The resinous plastic substrate can be clad with the metal foil on one or both sides, depending upon the desired use, and can be rigid or flexible depending upon the composition of the resinous plastic substrate, the choice of reinforcement (if any), and the intended use of the board.
A number of polyphenylene ether compositions having favorable dielectric properties and utility in circuit board manufacture are known. However, due to deficiencies in one or more properties, many such compositions have not attained wide commercial use. In specific, while polyphenylene ethers are excellent dielectrics, deficiencies often are found in areas such as solvent resistance, flammability, solderability, and resistance to high temperatures. Moreover, times required for curing such compositions typically are too long for effective manufacture of circuit boards in large volume. Polyphenylene ethers are often combined with polyepoxides in an attempt to improve upon the aforementioned properties, but such combinations have not been found to be wholly satisfactory either.
In addition to excellent dielectric properties, resinous compositions to be used for printed circuit board manufacture should be highly flame-retardant. A V-1 rating, as determined by Underwriters Laboratories test procedure UL-94, is universally required, with V-0 usually being necessary. The V-0 rating requires a flame-out time (FOT) of not more than 10 seconds in any trial and a cumulative FOT of not more than 50 seconds for five samples. As a practical matter, a maximum cumulative FOT of 35 seconds often is mandated by purchasers.
The fabricated board should not lose substantial weight and its surface should not be appreciably marred by contact with methylene chloride, a solvent commonly used for cleaning. Since conductive connections with the printed circuit typically are made by soldering, the board must be solder-resistant as evidenced by the lowest possible percent increase in thickness (Z-axis expansion) when exposed to liquid solder at 288.degree. C. In addition to all these properties of the cured material, a relatively short curing time is highly desirable.
In preparing rigid metal-clad boards, it is common to form individual lamina, commonly called prepregs, by formulating a resinous binder composition made from epoxy, modified styrene, or the like. A solvent solution of the resin is placed in an apparatus known as a "dip tank." Continuous webs of reinforcement can be preimpregnated in the tank and then dried in a vertical or horizontal treating tower or oven. Normally, the resin is partially cured or B-staged after exiting the treater tower or oven. The copper foil, optionally coated with an adhesive, is placed on one side of the prepreg and subjected to heating under pressure to effect a bond between the metal foil and the substrate. Multiple prepregs can be used in forming a single composite board. Additionally, multilayer printed wiring boards will have a number of interposed laminae and copper sheets.
Pressing of the boards can be effected in a press by placing the foil/substrate structure between the platens and closing the press, or a continuous belt can be used. The curing cycle in the press will depend upon the nature and thickness of the laminate, the time and temperature of the cycle being those required to cure the substrate, and the bonding adhesive layer, if present. Sufficient pressure is required to effect adequate flow of the adhesive and/or substrate resins in order to wet-out and bond adequately. The pressure must be sufficient to prevent blistering which is due to the release of gases resulting either from retained volatiles in the substrate or adhesive layers, or resulting from by-products of the curing process.
U.S. Pat. No. 3,716,449 discloses a process utilized in papermaking known as the Wiggins Teape process. This same basic process has been found to be useful in the preparation of reinforced polymeric composites. In the Wiggins Teape process, the polymeric blend is dispersed in an aerated surfactant foam, which is then deposited on a foraminous layer and collapsed to form a web. The web then is heat consolidated under conditions appropriate for the particular resin system and adhesive (if any). | {
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In recent years, mobile communication terminals, in particular, have been provided with more advanced functions in association with the advancement and proliferation of wireless communication modes. In addition, due to the proliferations of mobile terminals compatible with both domestic and international services, wireless LAN, and the like, it has been required that one wireless communication apparatus should be compatible with two or more wireless communication modes. Moreover, the frequency bands used by various wireless communications tend to become closer in association with the progress of the effective use of frequencies.
Conventionally, when two or more wireless communication modes are operated in a single wireless communication apparatus, a transmission wave of a certain mode raises the noise floor of the reception band of another mode. This phenomenon has deteriorated the reception sensitivity of another communication mode.
Specifically, in a multimode communication apparatus that incorporates a plurality of components (communication units) each provided with a transmitter unit and a receiver unit, degradation in wireless communication characteristics occurs mutually when the respective units are operated at the same time. When one of the units transmits a radio wave, the transmission wave raises the noise floor of the reception band in another system, degrading the reception sensitivity of the other system(s), in particular, in the case that the frequency bands used by the wireless communication modes of the units are close to one another. That is, the frame error rate (FER) and the bit error rate (BER), for example, increase.
In order to resolve such a problem, it is conceivable to provide the transmitter section of each of the units with various filters, such as variable frequency stop filter, band pass filter (BPF), and band elimination filter (BEF) (see Patent Document 1).
Nevertheless, since various filters such as mentioned above have high attenuation, transmission waves that pass through the filters suffers from great loss. Moreover, if another unit with a different wireless communication mode is added, it will become necessary to add a filter that is compatible with the frequency band of that system. Such addition of the filter brings about further power loss in pass band and an increase in size of the apparatus. An increase in power loss in pass band results in a shorter wireless communication distance and a narrower communication area.
Patent Document 1: JP-A-2004-222171
The present invention relates to a multimode communication apparatus that uses a plurality of wireless communication modes, and particularly, it is an object of the invention to provide a multimode communication apparatus that can suppress adverse effects that a transmission wave under one mode has on the communications of other modes. | {
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Once a petroleum well has been drilled and cased, it may be desirable to drill one or more additional sidetracked well bores that branch off, or deviate, from the primary well bore. Such multilateral well bores are typically directed toward different targets within the surrounding formation, with the intent of increasing the production output of the well.
Multilateral technology provides operators several benefits and economic advantages, such as tapping isolated pockets of hydrocarbons that might otherwise be left unproduced, and improving reservoir drainage so as to increase the volume of recoverable reserves and enhance the economics of marginal pay zones. By utilizing multilateral technology, multiple reservoirs can also be drained simultaneously, and thin production intervals that might be uneconomical to produce alone may become economical when produced together. Multiple completions from one well bore also facilitate heavy oil drainage.
In addition to production cost savings, development costs also decrease through the use of existing infrastructure, such as surface equipment and the primary well bore. Multilateral technology expands platform capabilities where slots are limited and eliminates spacing problems by allowing more drain holes to be added within a reservoir. In addition, by sidetracking damaged formations or completions, the life of existing wells can be extended. For example, sidetracked well bores may be drilled below a problem area once the casing has been set, thereby reducing the risk of drilling through troubled zones. Finally, multilateral completions accommodate more wells with fewer footprints, making them ideal for environmentally sensitive or challenging areas.
To maximize the productivity of multilateral completions, it is desirable to enlarge at least some of the sidetracked well bores to thereby increase the production flow area through such boreholes. By drilling a sidetracked well bore through a casing window, and then enlarging the sidetracked well bore beyond the casing window, the far reaches of the reservoir can be reached with a comparatively larger diameter borehole, thereby providing more flow area for the production of oil and gas.
However, conventional methods for drilling an enlarged sidetracked well bore require multiple trips into the primary well bore. For example, a first trip may be made into the primary well bore to run and set an anchored whipstock comprising an inclined face that guides a window mill radially outwardly into the casing to cut a window in the casing. The window mill is then tripped out of the primary well bore, and a drill bit is lowered in a second trip to drill the sidetracked well bore through the casing window. The diameter of the sidetracked well bore is thereby limited by the diameter or gauge of the drill bit that can extend through the casing window. Once the sidetracked well bore has been drilled, the drill bit is then tripped out of the primary well bore, and another drilling assembly, such as a drill bit followed by a reamer, for example, is lowered in a third trip into the primary well bore to extend and enlarge the sidetracked well bore. It is both expensive and time consuming for an operator to make multiple trips into a primary well bore to drill and enlarge a single sidetracked well bore, and such concerns are only compounded when drilling more than one sidetracked well bore in a multilateral completion.
Thus, in recent years, a window milling bit comprising diamond cutters has been developed that is operable to mill a window through a standard metal casing and drill a sidetracked well bore through the casing window in a single trip into the primary well bore. This window milling bit with diamond cutters thereby eliminates one trip into the primary well bore, but at least another trip is still required to enlarge the sidetracked well bore. Therefore, a need exists for apparatus and methods that enable milling a window through a casing in a primary well bore, and drilling an enlarged sidetracked well bore through the casing window in one trip into the well bore.
To perform such a sidetracking operation, it would also be advantageous to provide a single cutting device capable of both milling the casing and drilling an enlarged sidetracked well bore. Such a device is desirable to provide a more compact drilling assembly for increased maneuverability and control while drilling the enlarged sidetracked well bore through the casing window.
Further, when operating a window milling bit to mill casing and drill formation, whether drilling an enlarged borehole or not, the cutting structures on such a bit may be worn down during operation. Thus, a need exists for a cutting device with multiple cutting structures adapted to recover gauge as the device is used to mill through casing and/or drill into formation. In addition, it may be desirable for the window milling bit to have at least a first cutting structure to perform the milling operation, and at least a second cutting structure to perform the drilling operation. Thus, a need exists for a cutting device with multiple cutting structures wherein at least one of the cutting structures is selectively presented when desired by the operator. Such a cutting device would be useful for many other purposes, including drilling through different types of formation rock, or replacing worn cutting structures when drilling a lengthy borehole, for example.
The present invention addresses the deficiencies of the prior art. | {
"pile_set_name": "USPTO Backgrounds"
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The proliferation of available streaming content is increasing at exponential levels that will soon reach many millions if not billions of available streaming content for viewing. Conventionally, broadcast media has been provided by television or cable channels that are typically provided by a relatively small number of content providers. However, with the ubiquitous nature of media creation and publishing tools, individuals are able to become prolific content creators. This has resulted in the exponential growth of available streaming content as well as available channels for streaming content. As a result, video creators are constantly searching for ways to attract and retain viewers. Understanding how viewers perceive and consume their videos is essential for discovering new and improved ways to achieve this goal. | {
"pile_set_name": "USPTO Backgrounds"
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Portable, soft-sided insulated containers may be used to transport articles that may best be served cool, such as beverages or salads, or warm, such as appetizers, hot dogs, and so on. Such containers are also used to carry liquids, whether hot liquids, such as soup containers, coffee or tea, or cold liquids such as beer, soft drinks, or other carbonated beverages, juices and milk. The containers are typically made in a generally cube-like shape, whether of sides are of equal length or not, having a base, four upstanding walls, and a top. The top wall is often a lid which opens to permit articles to be placed in, or retrieved from, the container. In soft-sided coolers, the main closure of the lid has tended to depend on the closing of a zipper, often a zipper running around three sides of a rectangle, with the fourth side being hinged.
It may be that some people would prefer not to have the sometimes cumbersome bother of opening the main closure, particularly if it requires the use of two hands, and if the process is awkward. They may prefer the use of a closure member that can be used with one hand, such as a zipperless closure member. Further, while opening the main closure member to fill the insulated container may be appropriate, and may occur in the kitchen or at another loading location where full access is desired and convenient, it may also be that when the unit is being used, opening the full main closure member may lead to more rapid heat loss (or gain, as may be) than if a smaller, auxiliary, closure member were used.
Furthermore, when an object is removed from the cooler, it may be that it would be convenient to have some place to rest that object temporarily. It may be that one wishes to put down a drink in a glass while reaching for a can of ginger ale or cola to freshen a drink, or to have a place where a lemon or lime can be sliced suitably. For whatever reason, it may be desirable to have a place for resting objects, even if merely to free one's hand to close the cooler. It may also be convenient for that resting place to be adjacent to the easily accessed opening; for that resting place to be firm, such that objects placed upon it may be less prone to wobble or tip, and for that resting place to be washable such that it may be wiped clean with a cloth should drinks or other objects be spilled on it. Further still, it may be convenient for that resting place to be such as may discourage, or limit, the extent to which objects may slide if the surface is not precisely level, as may be the case at a picnic, at a sporting venue, or at the beach.
In the event that the insulated container is a collapsible insulated container that may be collapsed or folded to a collapsed position when not in use, it may be that a rigid working surface, or table top, however it may be called, may be mounted in such a way as not to obstruct movement of the assembly to the folded or collapsed, or storage condition. Alternatively, the rigidity of the work surface may define a frame, or stiffening member, that, when in place, may tend to encourage the assembly to maintain its shape when in use.
It may also, or alternatively, be helpful to have a work surface that may tend to catch spills, and that may discourage items from falling off, or that may | {
"pile_set_name": "USPTO Backgrounds"
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Computer networks are continually being enhanced to improve the ways in which people communicate. For example, the Internet has enabled people to gain access to vast amounts of information. Besides the Internet, networks are utilized to facilitate the transfer of files between computers as well as to connect computers to printers, scanners, cameras and a whole host of other devices. The physical characteristics of the network can take on many different characteristics. For example, the actual connections may be made through coax or twisted pair cables. Routers and hubs may be utilized to connect multiple computers to one another and to direct network traffic. The protocol utilized by the network may vary. For example, the protocol may be TCP/IP, IPX/SPX, or AppleTalk.
Although most often thought of as a means for computers to communicate with one another, networks are now being utilized for other forms of communications. For example, in a security system, security cameras may communicate to a server computer via an IP network rather than stream analog video information over a video cable. This may make it easier to add security systems where an IP network already exists. Furthermore, in a networking environment, the computer and camera could be a great distance apart whereas the distance may be much shorter if the analog video were transferred directly over a cable.
Some network systems allow for the transfer of power over the network cable, by coupling DC voltages and currents to the conductors. For example, one way to transfer power may be to utilize unused conductors in the network cable. Another method may be to transfer the power utilizing the same conductors, but superimposing the power by utilizing isolation transformers. The second method may conform to IEEE 802.3af. This method may work well for most situations. However, under certain conditions the characteristics of the transformers may change and thus impede the transfer of data.
Further limitations and disadvantages of conventional and traditional approaches will become apparent to one of skill in the art, through comparison of such systems with some aspects of the present invention as set forth in the remainder of the present application with reference to the drawings. | {
"pile_set_name": "USPTO Backgrounds"
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In U.S. Pat. No. 4,930,600 Kumar and Kumar have presented the background of the existing state of the art in rail lubrication systems. Those comments still apply. None of the lubricators available prior to the U.S. Pat. No. 4,930,600, including both on-board and wayside lubricators, adequately met the demands of both tangent and curved track. Prior lubricators did not apply the lubricant correctly and effectively on tangent track. They also did not control and change the amount of lubricant depending on the tonnage being hauled, angle of attack of the wheel on the rail, and environmental conditions such as rain and temperature. Prior lubricators were not aimed at reducing the force with which the flange contacts with the rail. The system patented by Kumar and Kumar in U.S. Pat. No. 4,930,600 overcame these problems and provided the intelligent controls for the application of both the Top Of the Rail (TOR) which is a consumable lubricant and the Rail Gage Side (RAGS) which is a long life lubricant. The lubricants used for TOR and RAGS awe preferably bio-degradable for environmental benefits. The present invention is an extension of the development in the U.S. Pat. No. 4,930,600 patent. | {
"pile_set_name": "USPTO Backgrounds"
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It has been conventionally considered that the capacitance of an electric double-layer capacitor is almost proportional to the surface area of polarizable electrodes (such as carbon electrodes) provided as an anode and a cathode constituting the electric double-layer capacitor. Therefore, in an attempt to increase capacitance by increasing the surface area of a carbon material of the carbon electrodes when the carbon electrodes are used as polarizable electrodes, various studies have been made.
For example, as a carbon material for a carbon electrode, activated carbon has so far been frequently used. Such activated carbon is generally produced by activating so-called hard-graphitization carbon, which is obtained by carbonizing coconut shell, wood chip, coal and phenol resin, with a gas such as water vapor or with a chemical agent such as an alkali metal hydroxide. However, the activated carbon produced from such hard-graphitization carbon has a problem in that the capacitance per unit volume does not increase proportionally with an increase of the specific surface area. To explain more specifically, in either one of activation reactions of hard-graphitized carbon with a gas or a chemical agent, fine pores are formed from the surface of a particle by an oxidative reaction. Therefore, as the activation reaction proceeds, the amount of loss due to oxidation increases. As a result, the activated carbon is low in bulk density. When such activated carbon is used in an electrode material, the bulk density of the resultant electrode decreases. Therefore, even if the capacitance per unit mass of the electrode increases, an increase of density of capacitance per unit volume of the electrode is limited. In addition, such activated carbon is low in electric conductivity due to hard-graphitization carbon. Because of this, the internal resistance of the electrode increases.
On the other hand, activated carbon obtained by activating easy-graphitization carbon has been proposed, which is obtained by infusibilizing/carbonizing mesophase pitch and a mesophase pitch carbon fiber obtained by spinning the mesophase pitch or by carbonizing petroleum coke and coal-tar pitch coke, etc., with an alkali metal hydroxide. When the easy-graphitization carbon is activated with an alkali metal hydroxide, activated carbon is produced in high yield and with high bulk density. Therefore, an electrode having a high bulk density can be formed. Furthermore, the density of capacitance per unit volume can be increased. Moreover, the activated carbon produced from the easy-graphitization carbon generally has a high electrical conductivity compared to that produced from hard-graphitization carbon. Therefore, the activated carbon produced from the easy-graphitization carbon has also an advantage of easily reducing the internal resistance of an electrode.
However, the mesophase pitch and a mesophase pitch carbon fiber obtained by spinning the mesophase pitch are expensive materials themselves. In addition to this problem, there is another problem in that since an infusibilizing/carbonizing process must be performed prior to an activation process, manufacturing steps becomes complicated, raising manufacturing cost more and more. A still another problem resides in that since oxygen is introduced by an infusibilizing reaction, the degree of graphitization decreases, with the result that the internal resistance of an electrode does not decrease so much.
On the other hand, JP-A-10-199767 (Patent Document 1) proposes a method of carbonizing petroleum coke or coal pitch coke to obtain a product satisfying conditions: a volatile content of 1.0 to 5.0 wt. % and an H/C atom ratio of 0.05 to 0.30, followed by activating the product with an alkali metal hydroxide.
Furthermore, JP-A-2003-51430 (Patent Document 2) describes that a raw-material carbon composition, which has an HGI (Hardgrove Grindability Index, defined by ASTMD-409-71) of 50 or more, a microcrystalline-carbon interlayer distance: d002 of 0.343 nm or less, and a lattice constant of crystal: Lc002 of 3.0 nm or less, is activated with an alkali, and that a carbon material for an electrode of an electric double-layer capacitor having a large capacitance per unit volume can be obtained.
Patent Document 1: JP-A-10-199767
Patent Document 2: JP-A-2003-51430 | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The invention is directed to the field of tools for metal forming and the like.
2. Description of the Prior Art
In the field of die assemblies adapted for use in crimping or otherwise deforming metallic terminals for joining or splicing articles to one another, two principle modes of operation are generally utilized. The more conventional devices generally comprise a pair of mating die members movable towards one another along a common axis to provide a given compressive force to a deformable terminal or like element seated therebetween. Proliferous examples of such die assemblies may be found in the prior art and are sufficiently well known to those skilled in the art. The other mode of operation utilizes longitudinal displacement of the connector through a restrictive orifice to extrudably deform the terminal or connector about one or more contained wires or conductors. An example of such device is disclosed in U.S. Pat. No. 3,739,470 issued June 19, 1973 to applicant and assigned to the assignee of the instant invention. In the latter method, the terminal must be fabricated from special material which must be extrudably deformable without fracture or damage occurring thereto in order to preserve the integrity of the connection. Furthermore, by virtue of the extrusion process, both the terminal and enclosed wires are elongated and reduced in cross-section to a significant degree upon completion of the operation, a condition which may be undesirable in many applications where the cross-sectional area of the completed joint or connection is of principle importance. The former conventional method of direct crimping, although used quite successfully in many applications, has the distinct drawback of requiring relatively high crimping forces when employed with the larger size conductors and associated terminals, thereby requiring the use of relatively bulky and expensive drive sources for use therewith. In many cases where such connections must be made in remote locations removed from a worksite, convenience of portability may become a major factor in the use thereof, whereby the weight and size of such prior art devices may seriously limit their applicability under such conditions. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The present invention relates to a single-phase motor with a conversion circuit. In particular, the present invention relates to the use of a driver integrated circuit (model no. [US79KUA]), which is generally used with a two-phase motor, with a single-phase motor by means of connecting the driver integrated circuit with an external conversion circuit before connection to the single-phase motor. The output of the driver integrated circuit drives the single-phase motor under the control of the conversion circuit.
2. Description of the Related Art
A typical driver integrated circuit of model no. [US79KUA] includes three functional modules and three terminals. As illustrated in FIG. 1, the [US79KUA] single-phase motor driver integrated circuit (IC) includes a DC voltage-regulating circuit module, a control and protection circuit module, and a Hall latch module. The DC voltage-regulating circuit module supplies stabilized DC voltage to the control and protection circuit module and the Hall latch module, respectively, thereby providing a stable operational condition for the driver IC. The control and protection circuit module includes an auto-restart circuit, a locked rotor shutdown circuit, a reverse voltage protection circuit, and a Zener diodes protect outputs circuit. The Hall latch module includes a Hall element, a Hall voltage amplifier, and a motor driver. The Hall element detects a change in the magnetic field during rotation of the rotor, and the detected weak voltage is amplified by the Hall voltage amplifier and then outputted to drive the motor driver connected to the outputs (OUT1 and OUT2). Thus, a change in the current providing an alternate on/off function is generated in the Hall latch module. The stator of the motor is thus inducted to thereby turn the rotor, and the rotor turns continuously.
FIG. 2 depicts an application circuitry of the conventional [US79KUA] driver integrated circuit and a two-phase motor. FIG. 3 is a diagram illustrating output waves of the conventional [US79KUA] driver integrated circuit, wherein the abscissa denotes time and the ordinate denotes voltage. Referring to FIG. 2, a DC voltage (3-18V) of a power-supply is inputted via Vcc to power the driver IC. In this case, the Hall element of the driver IC detects a specific period of a change in a magnetic field generated by the permanent magnet of the rotor. When the terminal OUT 1 is close, the current passes the Coil 1 to drive the rotor through a certain angle. Due to the change in the angular position of the rotor, the Hall element detects another period of the change in the magnetic field generated by the permanent magnet. At this time, the terminal OUT 1 is open and the terminal OUT2 is close such that the current passes the Coil 2 to drive the rotor through another certain angle. Referring to FIG. 3, the terminals OUT1 and OUT2 are alternately opened and closed in a synchronous manner to output square waves of identical frequency and inverted phases. Thus, the rotor is continuously driven by inducted repulsive forces generated by the Coil 1 and Coil 2 in alternative phases. However, such a driver IC can only be used with a two-phase motor having two coils; namely, it cannot be used with a single-phase motor having a single coil.
The primary object of the present invention is to provide a single-phase motor having a conversion circuit, wherein a [US79KUA] two-phase motor driver IC is connected to a single-phase motor via an external conversion circuit. The conversion circuit receives the output signals of the [US79KUA] driver IC to control alternate on/off of two transistors serially connected to two ends of a coil for a motor. The [US79KUA] two-phase motor driver IC can be selected to apply in a single-phase motor.
The secondary object of the present invention is to provide a single-phase motor having a conversion circuit, wherein the [US79KUA] two-phase motor driver IC can be used with a single-phase motor having a single coil and a simple structure. The coil structure is thus simplified, and the motor quality is improved.
A further object of the present invention is to provide a single-phase motor having a conversion circuit, wherein the [US79KUA] two-phase motor driver IC is connected to a single-phase motor via an external conversion circuit. The conversion circuit further comprises two sets of voltage-dividing circuits for reducing the power voltage to a proper extent. Thus, the available voltage of the motor is not limited by voltage feature of the [US79KUA] two-phase driver IC. As a result, the motor may work in a wider input voltage range.
The single-phase motor having a conversion circuit in accordance with the present invention comprises a [US79KUA] two-phase motor driver IC, a conversion circuit, and a coil for a motor. The driver IC includes two outputs that are serially connected to the conversion circuit and then connected to the coil. The conversion circuit includes two transistors respectively connected two ends of the coil. The outputs of the driver IC respectively send out alternate on/off signals to respectively turn the transistors on and off, thereby controlling directions of current passing the coil. Thus, the coil generates alternative magnetic fields as a result of alternative directions of the current to thereby drive the rotor. In addition, the conversion circuit comprises two sets of voltage-dividing circuits for reducing the power voltage to a proper extent such that the motor may work in a wider input voltage range. Thus, the available voltage of the motor is widened and not limited by voltage feature of the driver IC.
Other objects, specific advantages, and novel features of the invention will become more apparent from the following detailed description and preferable embodiments when taken in conjunction with the accompanying drawings. | {
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1. Field of the Invention
The present invention relates to aquarium filtration systems, and more particularly to external aquarium filtration systems with a removable filter cartridges.
2. Background
External aquarium filters pull water from the aquarium tank and pass the water through various physical, chemical, and biological filters. Mechanical filtering typically uses a floss material or the like to screen and remove solid waste material and debris. Chemical filtration reduces ammonia levels using carbon (charcoal) or zeolite. Biological filtration reduces harmful levels of undesirable bacteria using thermoplastic tubules for aerobic bacterial growth. These filtration systems and biological filtration in particular, are improved by increasing the amount of time the water remains in contact with the filtration medium. This time is referred to as “dwell time.”
Conventional filters that use removable/disposable filter cartridges, such as that available with the commercially available Whisper Power Filter or the Marineland Penguin Filter, typically are only able to put the water to be cleaned through a relatively thin layer of cartridge with carbon held within the cartridge. The amount of dwell time of the water within the cartridge in contact with the filter material is therefore limited. In contrast, the AquaClear filter manufactured by the Hagen Corporation, which does not use cartridges, brings water to be filtered from the bottom of the filter through a sponge layer and then through a bag of carbon or other filter material. The water rises up from the bottom of the filter and, under pressure, overflows back into the tank. While this design advantageously increases dwell time, it does so at the expense of the user's convenience. Compared with cartridge filters, this design requires substantial more time and inconvenience to change filter material.
A need, therefore, exists for a filtration system that both provides the convenience of a disposable cartridge filtration system and the improved performance of a system that has an improved dwell time. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
This invention pertains to the field of anti-lock brake systems which are employed in wheeled vehicles to prevent the locking or skidding of the vehicle wheels when the vehicle brakes are applied. More specifically, this invention pertains to the field of anti-lock brake systems which actively control the braking force produced by the vehicle brakes in response to a sensed incipient wheel skid condition in order to produce a maximum braking effort until such a time as the possibility of a dangerous wheel skid no longer exists.
2. Description of Related Art
Various systems have been proposed for preventing the locking or skidding of the vehicle wheels when the vehicle brakes are applied. A current trend in automotive hydraulic brake system design is to provide each brake line in the brake system with access to a drain and an auxiliary pressure source. A first solenoid valve is employed between the brake line and the drain to permit controlled draining of brake fluid from the brake line when it is necessary to relieve hydraulic braking pressure in the brake line. The pressure source is selectively communicated with the brake line through a second solenoid valve to readmit the drained brake fluid into the brake line when it is necessary to increase the hydraulic braking pressure. In this manner, the two solenoid valves can be selectively controlled in order to modulate the hydraulic pressure at the wheel cylinder between a low and a high level. Such modulation of the hydraulic pressure at the wheel cylinder is generally controlled by a microprocessor and occurs independently of the hydraulic pressure in the operator controlled master cylinder. Specifically, during braking, the microprocessor continually receives inputs from wheel speed sensors and calculates the magnitudes and/or rates of change of angular deceleration of the vehicle wheels. From this information, the microprocessor determines whether or not any incipient wheel skid conditions exist. If an incipient wheel skid condition exists at any particular wheel, the microprocessor immediately isolates the brake line leading to the particular wheel from the master cylinder and then outputs a first electrical signal to energize the first solenoid valve to establish communication between the brake line and the drain. Thus, the hydraulic pressure in the wheel cylinder is immediately reduced to a low level and stays reduced until such a time as the microprocessor determines that the particular wheel is rolling again. When the wheel has regained traction (that is, when the wheel is rolling again), the microprocessor immediately outputs a second electrical signal to energize the second solenoid valve to establish communication between the pressure source and the brake line, thereby allowing the pressure source (which can typically comprise a hydraulic pump driven by an electric motor) to pump the drained brake fluid back into the brake line. Consequently, the hydraulic pressure in the wheel cylinder increases and continues to increase until such a time as the microprocessor determines that the particular wheel is skidding again. Thereafter, the microprocessor must immediately output the first electrical signal again until it determines that the particular wheel is rolling, followed by the second electrical signal, then the first, and so on. Additionally, some of the current anti-lock brake systems provide valve means for allowing the microprocessor to maintain the hydraulic pressure in the wheel cylinder constant for brief periods of time. One example of this kind of system is disclosed in U.S. Pat. No. 4,676,353, herein incorporated by reference. All in all, it is the current trend in anti-lock brake systems to modulate (i.e increase or decrease) the hydraulic pressure in the wheel cylinders of skid controlled wheels at a rate of between 7 and 20 times a second.
It has been known that the maximum possible braking force between a wheeled vehicle and, for example, a dry road surface is achieved when the slip between the decelerating wheels and the road surface is maintained at a level between about 10% and 20%. That is to say, in order to stop a wheeled vehicle in the shortest possible distance, the vehicle wheels should be retarded with a force which causes the tire surfaces on the wheels to slip (in the braking or decelerating direction) relative to the road surface by an amount (i.e a distance) equal to between about 10% and 20% of the distance travelled by the vehicle during braking.
It becomes apparent then that the current anti-lock braking systems as described above are not designed to provide the maximum possible braking of a vehicle during a skid control operation because they are not designed to maintain the wheel slip during deceleration at an amount which is between about 10% and 20%. Rather, these systems have been designed to prevent the vehicle wheels from locking completely and to ensure that a good (though not optimum) level of traction is maintained during braking.
Moreover, owing to their relative complexity, the current anti-lock brake systems have heretofore been offered only as original equipment on new vehicles. No system has been proposed which meets the needs of those consumers who have bought vehicles in the past without anti-lock brakes systems but now want to retrofit such systems to their vehicles. That is, no after-market anti-lock brake systems are currently available.
The following patent documents, incorporated herein by reference, reveal brake systems which are similar in one or more respects to the anti-lock brake system of the present invention:
______________________________________ Origin Document Number ______________________________________ U.S. 3,731,979 U.S. 4,705,323 U.S. 4,826,256 Japan 57-140263(A) Japan 61-139927(A) Japan 61-139928(A) European Pat. Office 152344(A) Fed. Rep. Germany DE-O 2154227 Fed. Rep. Germany DE-O 3318326 Fed. Rep. Germany DE-O 3441380 ______________________________________ | {
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It is well known in motor vehicles to provide a trim panel for covering the vehicle interior structure such as the instrument panel or the door.
It is desirable to provide such a trim panel having regions of different aesthetic characteristics. For example, it may be desirable to provide a two-tone instrument panel cover or a two-tone door trim panel having regions of different color.
Vehicle trim panels are typically comprised of a cloth or vinyl covering over a rigid substrate. One method for manufacturing such trim panels is to load a sheet of vinyl in a mold and then pour urethane into the mold to adhere to the sheet vinyl. The cured urethane provides a rigid substrate panel to which the vinyl cover is adhered. Thus, by choosing the color of the vinyl sheet, the trim panel either matches or contrasts with the vehicle interior according to the choice of the vehicle interior designer.
The present invention provides a new and improved method for manufacturing vehicle interior trim panels such as door panels and instrument panels in which different regions of the trim panel have different colors or other aesthetic characteristics. | {
"pile_set_name": "USPTO Backgrounds"
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Computer security vulnerabilities come in all shapes and sizes; resultantly, computer security strategy must be varied and diverse to protect against exploitation of those vulnerabilities. Phishing is a particularly interesting challenge for computer security implementation because it is not solely a technological problem, as phishing relies on exploitation of a vulnerability not easily rectified—human fallibility.
While computer network users can be trained to recognize and report phishing attacks, it is difficult for such training to achieve learning retention levels necessary for a network to actually achieve sufficient protection from phishing-based attacks; after all, it is only necessary that for one user of the computer network to make a mistake for a phishing attack to succeed.
Traditionally, this problem has been addressed by performing phishing risk analysis. In such traditional methodologies, network administrators (or third parties) conduct phishing campaigns on network users to determine which phishing campaigns users may be most susceptible to, which users are highly vulnerable to such attacks, and other important information.
Unfortunately, generating sophisticated phishing campaigns is typically a highly manual process that requires either constant administrator involvement or contracting with an external firm (which can be costly and increase exposure). Thus, there is a need in the computer security field to create new and useful methods for phishing risk analysis. The embodiments of the present application provide such new and useful methods. | {
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1. Field
The present disclosure relates to an exoskeleton mechanism, and more particularly, to an exoskeleton mechanism for assisting joint movement of a human or a robot (a “wearer”).
2. Description of the Related Art
An exoskeleton mechanism is mounted to an arm or leg of a patient, who feels inconvenience in the limb, to assist in or reinforce the muscular power of the patient or mounted to a robot so that a joint of the robot generates a force over a designed torque.
The exoskeleton mechanism is configured so that a frame corresponding to a physique of the limb (hereinafter, generally referred to as an “arm”) of the wearer allows the muscle of the arm to smoothly move. The exoskeleton mechanism includes a plurality of frames and links as well as motors required for driving the frames and links so as to make the same movement as the arm.
The exoskeleton mechanism should be configured to ensure convenient wearing and also to allow the wearer to easily take off at emergency. In addition, the exoskeleton mechanism should ensure precise operation and precise detection in order to prevent an impractical force from being applied to the wearer who wears the exoskeleton mechanism.
One of conventional exoskeleton mechanisms for limb power assistance uses a ring-type guide rail, which is not easily worn or taken off by the patient. In addition, due to the use of the ring-type guide rail, the exoskeleton mechanism has a great volume, which may frequently disturb the movement of the patient.
Moreover, since a motor for connecting links is formed to protrude to the side of the frame, the exoskeleton mechanism has a great volume, and designing the exoskeleton mechanism is difficult. | {
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As is known in the art, it is frequently desirable to detect and segment an object from a background of other objects and/or from a background of noise. One application, for example, is in MRI where it is desired to segment an anatomical feature of a human patient, such as, for example, a vertebra of the patent. In other cases it would be desirable to segment a moving, deformable anatomical feature such as the heart.
In 1988, Osher and Sethian, in a paper entitled “Fronts propagation with curvature dependent speed: Algorithms based on Hamilton-Jacobi formulations” J. of Comp. Phys., 79:12-49, 1988, introduced the level set method, it being noted that a precursor of the level set method was proposed by Dervieux and Thomasset in a paper entitled “A finite element method for the simulation of Raleigh-Taylor instability”. Springer Lect. Notes in Math., 771:145-158, 1979, as a means to implicitly propagate hypersurfaces C(t) in a domain Ω⊂Rn by evolving an appropriate embedding function φ: Ω×[0,T]→R, where:C(t)={xεΩ|φ(x,t)=0}. (1)
More generally, an embedding function is a real-valued height function \phi(x) defined at each point x of the image plane, such that the contour C corresponds to all points x in the plane where \phi(x)=0:C={x|\phi(x)=0}
This is a way to represent a contour C implicitly. Rather than working with a contour C (moving the contour etc), one works with the function \phi. Moving the values of \phi will implicitly move the “embedded” contour. This is why \phi(x) is called an “embedding function”—it embeds the contour as its zero-level or isoline to value 0.
The ordinary differential equation propagating explicit boundary points is thus replaced by a partial differential equation modeling the evolution of a higher-dimensional embedding function. The key advantages of this approach are well-known: Firstly, the implicit boundary representation does not depend on a specific parameterization, during the propagation no control point regridding mechanisms need to be introduced. Secondly, evolving the embedding function allows to elegantly model topological changes such as splitting and merging of the embedded boundary. In the context of shape modeling and statistical learning of shapes, the latter property allows to construct shape dissimilarity measures defined on the embedding functions which can handle shapes of varying topology. Thirdly, the implicit representation, equation (1), naturally generalizes to hypersurfaces in three or more dimensions. To impose a unique correspondence between a contour and its embedding function one can constrain φ to be a signed distance function, i.e. |∇φ|=1 almost everywhere.
The first applications of the level set method to image segmentation were pioneered in the early 90's by Malladi et al. in a paper entitled “A finite element method for the simulation of Raleigh-Taylor instability: Springer Lect. Notes in Math., 771:145-158, 1979, by Caselles et al. in a paper entitled “Geodesic active contour.” In Proc. IEEE Intl. Conf. on Comp. Vis., pages 694-699, Boston, USA, 1995, by Kichenassamy et al. in a paper entitled “Gradient flows and geometric active contour models”: In IEEE Intl. Conf. on Comp. Vis., pages 810-815, 1995 and by Paragios and Deriche in a paper entitled “Geodesic active regions and level set methods for supervised texture segmentation”: Int. J. of Computer Vision, 46(3): 223-247, 2002. Level set implementations of the Mumford-Shah functional, see paper entitled: “Optimal approximations by piecewise smooth functions and associated variational problems”: Comm. Pure Appl. Math., 42:577-685, 1989 [14] were independently proposed by Chan and Vese, see paper entitled “Active contours without edges”: IEEE Trans. Image Processing, 10(2):266-277, 2001 and by Tsai et al. in a paper entitled “Model-based curve evolution technique for image segmentation”: In Comp. Vision Patt. Recog., pages 463-468, Kauai, Hawaii, 2001.
In recent years, researchers have proposed to introduce statistical shape knowledge into level set based segmentation methods in order to cope with insufficient low-level information. While these priors were shown to drastically improve the segmentation of familiar objects, so far the focus has been on statistical shape priors (i.e., what are “priors”) which are static in time. Yet, in the context of tracking deformable objects, it is clear that certain silhouettes (such as those of the beating human in an MRI application, or of a walking person in another application) may become more or less likely over time. Leventon et al. in a paper entitled “Geometry and prior-based segmentation: In T. Pajdla and V. Hlavac, editors, European Conf. on Computer Vision, volume 3024 of LNCS, pages 50-61, Prague, 2004. Springer, proposed to model the embedding function by principal component analysis (PCA) of a set of training shapes and to add appropriate driving terms to the level set evolution equation, Tsai et al. in a paper entitled “Curve evolution implementation of the Mumford-Shah functional for image segmentation, de-noising, interpolation, and magnification” IEEE Trans. on Image Processing, 10(8): 1169-1186, 2001 suggested performing optimization directly within the subspace of the first few eigenmodes. Rousson et al. see “Shape priors for level set representations”: In A. Heyden et al., editors, Proc. of the Europ. Conf. on Comp. Vis., volume 2351 of LNCS, pages 78-92, Copenhagen, May 2002. Springer, Berlin. and “Implicit active shape models for 3d segmentation in MRI imaging”: In MICCAI, pages 209-216, 2004 suggested introduction of shape information on the variational level, while Chen et al., see “Using shape priors in geometric active contours in a variational framework”: Int. J. of Computer Vision, 50(3):315-328, 2002 imposed shape constraints directly on the contour given by the zero level of the embedding function. More recently, Riklin-Raviv et al. see European Conf. on Computer Vision, volume 3024 of LNCS, pages 50-61, Prague, 2004. Springer, proposed to introduce projective invariance by slicing the signed distance function at various angles.
In the above works, statistically learned shape information was shown to cope for missing or misleading information in the input images due to noise, clutter and occlusion. The shape priors were developed to segment objects of familiar shape in a given image. However, although they can be applied to tracking objects in image sequences see [Cremers et al., “Nonlinear shape statistics in Mumford-Shah based segmentation”: In A. Heyden et al., editors, Europ. Conf. on Comp. Vis., volume 2351 of LNCS, pages 93-108, Copenhagen, May 2002. Springer], [Moelich and Chan, “Tracking objects with the Chan-Vese algorithm”, Technical Report 03-14, Computational Applied Mathematics, UCLA, Los Angeles, 2003] and [Cremers et al., “Kernel density estimation and intrinsic alignment for knowledge-driven segmentation”: Teaching level sets to walk. In Pattern Recognition, volume 3175 of LNCS, pages 36-44. Springer, 2004], they are not well suited for this task, because they neglect the temporal coherence of silhouettes which characterizes many deforming shapes.
When tracking a three-dimensional deformable object over time, clearly not all shapes are equally likely at a given time instance. Regularly sampled images of a walking person, for example, exhibit a typical pattern of consecutive silhouettes. Similarly, the projections of a rigid 3D object rotating at constant speed are generally not independent samples from a statistical shape distribution. Instead, the resulting set of silhouettes can be expected to contain strong temporal correlations.
In accordance with the present invention, a method us provided for detecting and tracking a deformable object having an sequentially changing behavior wherein the method develops a temporal statistical shape model of the sequentially changing behavior of the embedding function representing the object from prior motion and then applies the model against future, sequential motion of the object in the presence of unwanted phenomena by maximizing the probability that the developed statistical shape model matches the sequential motion of the object in the presence of unwanted phenomena.
In accordance with another feature of the invention, a method generates a dynamical model of the time-evolution of the embedding function of prior observations of a boundary shape of an object, such object having an observable, sequentially changing boundary shape; and subsequently using such model for probabilistic inference about such shape of the object in the future.
The method develops temporal statistical shape models for implicitly represented shapes of the object. In particular, the shape probability at a given time depends is a function of the shapes of the object observed at previous times.
In one embodiment, the dynamical shape models are integrated into a segmentation process within a Bayesian framework for level set based image sequence segmentation.
In one embodiment, optimization is obtained by a partial differential equation for the level set function. The optimization includes evolution of an interface which is driven both by the intensity information of a current image as well as by a prior dynamical shape which relies on the segmentations obtained on the preceding frames.
With such method, in contrast to existing approaches to segmentation with statistical shape priors, the resulting segmentations are not only similar to previously learned shapes, but they are also consistent with the temporal correlations estimated from sample sequences. The resulting segmentation process can cope with large amounts of noise and occlusion because it exploits prior knowledge about temporal shape consistency and because it aggregates information from the input images over time (rather than treating each image independently).
The development of dynamical models for implicitly represented shapes and their integration into image sequence segmentation on the basis of the Bayesian framework draws on much prior work in various fields. The theory of dynamical systems and time series analysis has a long tradition in the literature (see for example [A. Papoulis, Probability, Random Variables, and Stochastic Processes, McGraw-Hill, New York, 1984]). Autoregressive models were developed for explicit shape representations among others by Blake, Isard and coworkers [A. Blake and M. Isard. Active Contours. Springer, London, 1998]. In these works, successful tracking results were obtained by particle filtering based on edge-information extracted from the intensity images. Here, however, the method of the present invention, differs from these in three ways: Here the dynamical models are for implicitly represented shapes. As a consequence, the dynamical shape model can automatically handle shapes of varying topology. The model trivially extends to higher dimensions (e.g. 3D shapes), since it does not need to deal with the combinatorial problem of determining point correspondences and issues of control point re-gridding associated with explicit shape representations. The method according to the present invention, integrates the intensity information of the input images in a statistical formulation inspired by [Zhu, Yuille 1996, Chan, Vese 1999]. This leads to a region-based tracking scheme rather than an edge-based one. The statistical formulation implies that—with respect to the assumed intensity models—the method optimally exploits the input information. It does not rely on a pre-computation of heuristically defined image edge features. Yet, the assumed probabilistic intensity models are quite simple (namely Gaussian distributions). More sophisticated models for intensity, color or texture of objects and background could be employed. The Bayesian aposteriori optimization is solved in a variational setting by gradient descent rather than by stochastic sampling techniques. While this limits the algorithms used by the invention to only track the most likely hypothesis (rather than multiple hypotheses), it facilitates an extension to higher-dimensional shape representations without the drastic increase in computational complexity inherent to sampling methods.
Recently, Goldenberg et al. [Goldenberg, Kimmel, Rivlin, and Rudzsky, Pattern Recognition, 38:1033-1043, July 2005.] successfully applied PCA to an aligned shape sequence to classify the behavior of periodic shape motion. Though this work is also focused on characterizing moving implicitly represented shapes, it differs from the present invention in that shapes are not represented by the level set embedding function (but rather by a binary mask), it does not make use of autoregressive models, and it is focused on behavior classification of pre-segmented shape sequences rather than segmentation or tracking with dynamical shape priors.
The details of one or more embodiments of the invention are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the invention will be apparent from the description and drawings, and from the claims.
Like reference symbols in the various drawings indicate like elements. | {
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With increasing development of industries, robot manipulators having articulated arm have been applied to replace manpower for improving production efficiency and reducing cost. The tool or a tool module capable of carrying the tool thereon is connected with the end-shaft of the articulated arm to achieve various applications, for example tightening screw.
At present, the robot manipulator can be roughly divided into three types. In the first-type robot manipulator, the tool is directly connected with the end-shaft of the articulated arm of the robot manipulator. In the second-type robot manipulator, the tool module is connected with the end-shaft of the articulated arm, the work position of the tool carried by the tool module is fixed, and a center line of the tool and the axis of the end-shaft are parallel and apart from each other with a distance. In the third-type robot manipulator, the tool module is connected with the end-shaft of the articulated arm of the robot manipulator, and an inclination angle of the tool carried by the tool module can be adjusted so as to change the work position of the tool according to the practical requirements by hand.
However, the three types of robot manipulators have respective drawbacks. For the first-type robot manipulator, the tool is directly connected with the end-shaft of the articulated arm, and the work position of the tool cannot be changed. Under this circumstance, the form and the length of the tool are limited by the accommodation space below the end-shaft of the articulated arm. Consequently, the applicability and the working range of the tool are limited. For the second-type robot manipulator, the work position of the tool cannot be changed similarly so that the working range of the tool is limited. For the third-type robot manipulator, the drawbacks of the above-mentioned first-type robot manipulator and second-type robot manipulator are overcome. Nevertheless, the inclination angle of the tool carried by the tool module should be adjusted by hand, which causes the complexity of use and reduces the production efficiency.
Various robot manipulators are developed for solving the problems of the above-mentioned three types of robot manipulators, but the robot manipulators have the drawbacks of limiting and reducing the working range, for example the working range of the tool is smaller than the working range of the end-shaft of the articulated arm of the robot manipulator.
Therefore, there is a need of providing a tool driving module and a robot manipulator employing the same to obviate the drawbacks encountered from the prior arts. | {
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During production processing of metals, such as steel, rolling of the metal is followed by controlled cooling. During the production processing, particularly the cooling process, a microstructure of the metal evolves and results in a final microstructure of the processed metal. The microstructure of the processed metal has an impact on many aspects of the metal's character, such as tensile strength.
Conventional microstructural analysis techniques are destructive and involve removing samples for analysis from, for example, the end of a coil of the processed material. This is time-consuming, costly, does not allow continuous monitoring, and assesses only a small fraction of the material processed.
When the processed material is steel, it is known that electromagnetic techniques can monitor steel phase transformations by detecting the ferromagnetic phase change due to the changes in electrical conductivity and magnetic permeability within the steel. Furthermore, if a coil is placed in the vicinity of the steel being processed, this results in a change in impedance measurements for the coil because conductivity and permeability are influenced by the steel's microstructure. For example austenite, the stable phase of iron at elevated temperatures, is paramagnetic whereas the stable low temperature phases ferrite, pearlite, bainite and martensite are ferromagnetic below the Curie temperature of about 760° C. Steel properties vary strongly with the volume fractions of these phases, which are controlled largely by the cooling rate and alloy content of the steel.
However, problems exist in monitoring in real-time the electromagnetic properties of metals during processing. Many problems result from the environmental conditions associated with metal processing, such as heat, moisture, humidity, etc.
It is an object of embodiments of the invention to at least mitigate one or more of the problems of the prior art. | {
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This invention relates generally to the control of degreasing apparatus; more specifically, it concerns the control of solvent vaporization in such apparatus in such manner as to effect substantial energy savings.
In solvent vapor degreasers, heat is introduced into liquid solvent to produce the vapor in a tank, the vapor condensing on the parts to be cleaned, and draining to a sump along with the soil. Solvent vapor which does not condense on the parts is liquified and either sprayed on the parts or directly returned to the sump, or both.
Parts are typically introduced to the tank from the top, with the tank cover open, and the cover is closed when the tank is not in use. In the past, it was thought necessary to heat the liquid solvent at the same rate, whether or not parts were being cleaned, to maintain the solvent sufficiently vaporized and recirculating, as described, so that parts or work could be degreased quickly and efficiently. Such constant heating, however, is wasteful of energy, but no way was known to substantially reduce energy consumption while maintaining the apparatus in vapor-filled condition for ready use, in the unusually advantageous manner as is now afforded by the present invention. | {
"pile_set_name": "USPTO Backgrounds"
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In clinical use, infusion pumps allow automatically infusing liquid drugs or nutrients to patients intravenously at a set speed within a relatively longer time, which reduces the workload of medical staff and improves the security of infusion. According to different working principles, the infusion pumps are divided into different types, among which capacity pumps and syringe pumps are common. The capacity pumps can be driven by peristaltic pumps; and the syringe pumps can be driven by lead screw pumps. A motor drives a lead screw to rotate, changes rotational motion into linear motion, and pushes a plunger to inject liquid in a syringe into a patient's vein through a nut connected with the plunger. The precision of an infusion speed of the syringe pumps is higher than that of the capacity pumps, of which an error is about ±5%. However, in some clinical applications, as intravenous injection for new babies and insulin injection for diabetic patients, it is necessary to further improve the precision of the infusion speed of the syringe pumps. During infusion, it is also necessary to know the position of the plunger in the syringe. A common practice is to use a step motor, and it is also feasible to use a linear or rotating potentiometer or an optical decoder to control the infusion speed, but these methods still have problems of low precision, poor reliability and high manufacturing cost. | {
"pile_set_name": "USPTO Backgrounds"
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Managed investment portfolios are employed in a variety of contexts. In an example, an investor may contract with a financial services entity to provide investment of funds. In some instances, the financial services entity may be providing management of an investment portfolio with a particular goal that is not necessarily contractually guaranteed. For example, the investment portfolio may be in the form of a target date fund, in which funds are typically reallocated so as to reduce weighting toward equities as the target date is approached, thereby balancing risk of loss of account value due to poor equity market performance against the risk of failing to meet desired account values. By way of further example, the contract may include one or more guarantees associated with the performance of the investment portfolio. For example, an investment fund, such as a hedge fund, a mutual fund qualified under the Investment Act of 1940 or a fund of mutual funds or other investments, may have a contractual or insurance product associated guarantee. Such guarantees may include guarantees of a minimum income over a time period, a guarantee of a minimum account balance by a certain date, or other guarantees.
In still other examples, the financial services entity may be an insurance company that makes annuity products available. Such annuity products may include variable annuities having guarantees, such as guarantees of minimum withdrawals, minimum account values, and/or combinations of such guarantees.
Systems that implement processing of data related to managed investment portfolios with improved management of risks relating to fluctuations in market value of portfolio components would be desirable. | {
"pile_set_name": "USPTO Backgrounds"
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Implantable medical devices (IMDs) are often utilized in modern healthcare to facilitate the ability for patients to lead healthy and full lives. For example, IMDs such as pacemakers, implantable cardioverter-defibrillators (ICDs), neurostimulators, and drug pumps can facilitate management of a wide range of ailments, including, but not limited to, cardiac arrhythmias, diabetes, and Parkinson's disease. Patients and medical care providers can monitor the IMD and assess a patient's current and historical physiological state to identify conditions or predict impending events.
The sophistication of IMDs is evolving to provide for advanced computing and telemetry capabilities. There is a desire to use commercially available or non-proprietary telemetry communication protocols for wireless communication between implantable devices and external devices in order to more easily facilitate widespread provisioning of telemetry solutions. However, as commercially available telemetry protocols are employed to perform telemetry with an implantable device, the knowledge of how to initiate and conduct a telemetry session with the implantable device can become publicly available. As a result, it is important that the implantable device securely provide or receive sensitive information to or from only authorized devices. Accordingly, systems, methods, apparatus and computer-readable storage media that facilitate telemetry data communication security between an implantable device and an external device are desired. | {
"pile_set_name": "USPTO Backgrounds"
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The present invention relates to a passive device for indicating the incidence of electromagnetic radiation, as when a military vehicle is being sighted by an enemy laser-range finder.
In military engineering, enemy objects are measured with laser range finders in order to assure high accuracy of fire on the first firing. Such range finders operate in the near infrared (ruby laser at 694 nm, YAG laser at 1060 nm, or erbium laser at 1566 nm), or in the medium infrared (CO.sub.2 laser at 10.6 .mu.m).
The object of the present invention is to provide a passive means of warning to the driver of a military vehicle when his vehicle is being sighted by an enemy laser-range finder and, in this connection, to give him at least a general indication of the direction from which his vehicle is being sighted.
In U.S. Pat. No. 4,467,208, radiation detectors are disclosed as indicators of combustion or ignition processes and for the contact-less transfer of light signals between two relatively moving parts, the particular emphasis being on development of detector response to radiation in the ultraviolet region. These known detectors rely on a collector in the form of a light-guide fiber wound on a support, wherein the fiber has a core zone and an outer zone (cladding) of differing refractive index, and wherein the core material fluoresces when excited by ultraviolet radiation; the fluroescent light is conducted along the core to detector means at one or both ends of the core. These detectors are not suited to the above-stated object, but it is another object of the present invention to adapt and utilize some of the principles of said patent disclosure, in order to meet the directional and wavelength-response requirements for passive detection of a hostile laser sighting. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The present invention relates to a light emitting diode and more particularly to a light emitting diode which enhances a scattering of light produced by a light emitting element to produce a uniform, bright illumination in a wide range of angle.
2. Description of the Prior Art
An example of a known conventional light emitting diode is shown in FIG. 1 (see Japanese Patent Disclosure No. 2000-124507). This light emitting diode 1 includes a substrate 2, a pair of electrodes 3a, 3b formed on both sides of the substrate 2, a light emitting element 4 disposed on the substrate 2, bonding wires 5 electrically connecting the light emitting element 4 to the paired electrodes 3a, 3b, and a resin sealant 6 provided on the substrate 2 to seal the light emitting element 4 and the bonding wires 5. Small light scattering particles 7 are dispersed in the entire resin sealant 6 to scatter light and thereby increase the brightness of light produced.
The light emitting diode 1 constructed as described above, however, has the following drawback. Since the light scattering particles 7 are dispersed uniformly in a whole interior of the resin sealant 6, an upper surface of the resin sealant 6 (light projecting surface 8) opposing a light emitting surface (upper surface) of the light emitting element 4 has an improved brightness because of the light scattering by the light scattering particles 7, whereas side surfaces 9 of the resin sealant 6 that do not face the light emitting surface of the light emitting element 4 have a small light scattering effect by the light scattering particles 7 and therefore a low brightness. It is therefore not possible to produce a uniform, bright illumination in a wide range of angle.
An object of the present invention is to provide a light emitting diode which can enhance the scattering of light produced by a light emitting element to improve a brightness not only at an upper surface but also at side surfaces of a sealant covering the light emitting element, thereby providing a high, uniform brightness in a wider range of angle.
To achieve the above objective, a light emitting diode of the present invention comprises: a substrate; a pair of electrodes provided on the substrate; a light emitting element mounted on the substrate and electrically connected to the electrodes; a sealant provided on the substrate to seal the electrodes and the light emitting element; and a light scattering layer formed on an outermost layer of at least one surface of the sealant.
Since the light scattering layer is formed on the outermost layer of the sealant as described above, the light produced by the light emitting element is greatly refracted by the light scattering layer and rays of light reflected back into the interior of the sealant are also scattered inside the sealant, resulting in an enhanced light scattering action. This improves the luminance level not only at the upper surface of the sealant but also at its side surfaces, thus producing a bright, uniform illumination in a wide range of angle.
In one embodiment, the sealant is formed of a resin material which is transparent or has a light permeability, and the light scattering layer is formed of a paint film having a large number of light scattering particles dispersed therein or of a sheet member having a large number of light scattering particles mixed therein. The paint film is formed on the surface of the sealant by printing, and the sheet member is formed on the surface of the sealant by bonding.
The light scattering particles dispersed in the light scattering layer are fine particles of silicon dioxide or titanium oxide. Any desired luminance level can be obtained by adjusting a diameter and an amount of fine particles to be dispersed according to the use of the light emitting diode.
The light scattering particles are projected from the surface of the light scattering layer to form many protrusions and recesses in the surface, i.e., roughen or undulate the surface, to further enhance the light scattering action.
Such a light scattering layer is formed, for example, on the light projecting surface of the sealant which opposes the light emitting surface of the light emitting element. With the light scattering layer provided on the light projecting surface of the sealant, the light emitted from the light emitting surface of the light emitting element can be effectively refracted and reflected, resulting in an enhanced scattering of light in a wide range of angle. | {
"pile_set_name": "USPTO Backgrounds"
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The subject matter disclosed herein relates generally to methods and systems for displaying system parameter information, and more particularly to displaying system parameter information on a display of an ultrasound imaging system.
Diagnostic medical imaging systems typically include a scan portion and a control portion having a display. For example, ultrasound imaging systems usually include ultrasound scanning devices, such as ultrasound probes having transducers that are connected to an ultrasound system to control the acquisition of ultrasound data by performing various ultrasound scans (e.g., imaging a volume or body). The ultrasound systems are controllable to operate in different modes of operation and to perform different scans. The acquired ultrasound data then may be displayed, which may include images of a region of interest.
In order to ensure that clinically relevant information is determined, for example to ensure that proper measurements are obtained from a displayed image, certain system parameters may have to be set within predefined ranges or at predefined levels. For example, guidelines exist for use when performing certain measurements based on acquired ultrasound data or displayed images, such as nuchal translucency (NT) measurements.
Conventional methods for confirming systems parameters, which may include confirming that the parameters satisfy certain standards or guidelines, requires user intervention and interaction with the system. For example, a user may have to manually perform actions, such as measurement operations to confirm that system settings are within the defined standards or guidelines. The process performed by the user, often requiring several steps and/or iterations, may have to be performed numerous times in a single day and can be very time consuming. Accordingly, workflow or throughput is decreased as a result of the user required actions. | {
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The subject matter of the present invention is a method for the production of anhydrous potassium tert.butoxide by the reaction of aqueous potash lye with tert.butyl alcohol in a packed distillation column, in which the water is distilled out at the top using a withdrawing agent, and in the sump of the column, which is kept at the boiling temperature, an alcoholic solution of the potassium tert.butoxide is produced, which is continuously withdrawn and is then processed for the recovery of the potassium salt.
The preparation of potassium tert.butoxide, which is generally called potassium tert.butylate, from metallic potassium with anhydrous tert.butyl alcohol, is described in Houben-Weyl, Vol. IV/2 (1963), pp. 7-8, where mention is also made of the possibility of operating in an inert solvent. This procedure, however, has the disadvantage that the metallic potassium used is difficult to handle, and that the absolutely water-free tertiary butyl alcohol that is needed to achieve an end product of perfect quality is difficult to produce.
Even in the case of the known transalcoholization of a lower alcoholate with the desired higher alcohol, it is necessary, in order to produce anhydrous potassium tert.butoxide, to have an absolutely water-free tert.butyl alcohol, which is very difficult to produce in pure form. Also, in the case of the transalcoholization of lower potassium alcoholates with tert.butyl alcohol, the equilibrium is very strongly on the side of the starting substances, so that only a great excess of tert.butyl alcohol will lead to reasonable yields. This excess necessitates the boiling up of large amounts of butanol, which considerably increases the expenditure of energy required by this process.
The above disadvantages are largely removed by the process described in German Federal Pat. No. 968,903: the reaction water is distilled azeotropically and thus removed from the system. This process, however, has the disadvantage that, in the preparation of potassium tert.butoxide, the incrustations of solid potassium hydroxide that form on the column packings can lead to the clogging of the column. This disadvantage can be remedied by the use of small amounts of caustic potash solution, but this considerably reduces the yield.
The procedure described in German Federal Pat. No. 968,903 does mention azeotropic distillation of the alcohol by means of a withdrawing agent. In the process described therein, however, the alcohol of the water-alcohol azeotrope that is distilled out must be constantly replaced, and a complex recovery process is necessary for that purpose.
The problem therefore existed of conducting the production of anhydrous potassium tert.butoxide from caustic potash solution and tert.butyl alcohol such that the reaction can be performed continuously in a distillation column without clogging or incrustation, and the unreacted input substances can be recovered in a simple manner. Furthermore, in the new process a very pure end product is to be obtained, whose KOH content is as low as possible, preferably less than 1% by weight. | {
"pile_set_name": "USPTO Backgrounds"
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Electrical communication in and out of an array of tightly pitched wires can be difficult. It can be difficult because aligning an electrical bond pad to each wire without accidentally connecting to an adjacent wire can require a machine capable of high accuracy.
One structure for electrically connecting to wires of an array is called a multiplexing/demultiplexing architecture (a “mux/demux architecture”). The mux/demux architecture does not need an electrical bond pad to be connected or aligned with each wire of an array. Instead, one bond pad is typically connected to all of the wires of the array.
This one bond pad, however, does not allow communication with each wire of the array individually. To differentiate between wires, an address element, such as a transistor, can be contacted with each of the wires. For a 16-wire array, for instance, four transistors can be contacted with each wire. By selectively turning the transistors on and off, only one of the 16 wires can be permitted to communicate with the one bond pad. Manufacturing this mux/demux architecture is typically less expensive and more reliable than connecting a bond pad to each wire.
In FIG. 1, for instance, an array of wires 102 with a pitch 103 of about 1000 nanometers is electrically connected to one common node 104. A pitch is a distance between wires plus a width of one of those wires. Thus, a pitch of an array having wires that are one millimeter wide and spaced two millimeters apart is three millimeters. Wires 106 of the array 102 can be communicated with separately using a mux/demux architecture shown at numeral 108. This mux/demux 108 has four different address circuits 110, 112, 114, and 116, each of which communicates with a set of transistors 118 through two address lines. These address circuits can turn on or off the transistors 118 to which they are connected. By turning the transistors 118 on and off, only one of the wires 106 will have the same voltage as the voltage supply 120, while the rest of the wires 106 will have no voltage. Thus, only one of the wires 106 can be selected and therefore have the same voltage as the voltage supply 120.
For example, a third wire 122 can be selected if all four of the transistors 118 that are in contact with the third wire 122 are turned on. The transistors 118 of the third wire 122 are turned on by turning the address circuit 110 on, the circuit 112 on, the circuit 114 off, and the circuit 116 on. When on, the transistors 118 on the “Logical YES” side of each of the address circuits turn on and on the “Logical NOT” side turn off, and vice-versa. Address wires 124, 126, 128, and 130 are used to turn the address circuits 110, 112, 114, and 116 on or off, respectively.
One problem with this mux/demux architecture 108 is that it uses address elements (like transistors, diodes, and resistors) that typically need to be aligned with the wires during fabrication. Aligning these elements with the wires can be accomplished with typical processing machines if the wires of the array have a large enough pitch 103. For smaller pitches, however, the address elements of the mux/demux architecture 108 may not be alignable with wires of the array.
There is, therefore, a need for small-pitched devices and methods for addressing them electrically.
The same numbers are used throughout the disclosure and figures to reference like components and features. | {
"pile_set_name": "USPTO Backgrounds"
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Electronic systems, such as uninterruptible power supplies, generally include terminal blocks to facilitate connection between two groups of wires. It is common to use DIN terminal blocks with screw terminals that are fixed to the electronic system and whereby electrical connections are made. The terminal block is typically connected in a position that is space constrained. In such a space, multiple wire connections can be made, but the connections require manual intervention by a user or an electrician, who must clamp or punch down a wire to achieve connection. In larger systems, less flexible and larger gauge wire is required to complete electrical connections, which increases the difficulty for an electrician in connecting the wires, since the space in which the terminal block is positioned remains relatively small, despite the increase in wire size.
Further, it is often the case that setup of an electrical system requires use of clamping and wire routing tools to complete installation. Use of such tools in a confined space is necessary for proper connections, but difficult to manipulate by a user. It is therefore desirable to simplify wire connectivity in electronic devices. | {
"pile_set_name": "USPTO Backgrounds"
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Optical Coherence Tomography (OCT) is a non-invasive, and often non-contact, imaging technique. Light with a defined coherence length is radiated on a sample that reflects or re-emits light at different depths of penetration, which encodes information in the phase of the light. The light from the sample is superimposed with coherent light of a reference branch.
Classical OCT systems used a movable mirror in a mechanical reference branch for a variable optical length of the reference branch. Modern OCT systems use Fourier Domain OCT (FD-OCT). The performance of an OCT system may be characterized by its axial resolution and/or its axial scanning depth.
In some of the existing OCT systems, the axial resolution or the axial scanning depth may be limited by features of the OCT system. By way of example, an OCT system using Spectral Domain OCT (SD-OCT, which is one case of FD-OCT) may have an axial scanning depth limited by the spectral resolution of a spectrometer. As another example, an OCT system using Swept Source OCT (SS-OCT, which is another case of FD-OCT) may have an axial scanning depth limited mainly by the instantaneous linewidth δλ of the swept source. Further, an OCT system using FD-OCT may have an axial resolution that cannot be adjusted independently of its axial scanning depth. For example, the scanning depth Δzmax may be proportional to the axial resolution δzmin for a given spectral or temporal resolution of the detector. Moreover, an SS-OCT system may have a lower axial resolution, because its swept source of light is tunable over an overall spectral bandwidth Δλ (also referred to as tuning range) that is narrower than a complete bandwidth Δλ of a light source usable for SD-OCT without tuning of the light source. | {
"pile_set_name": "USPTO Backgrounds"
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Patent Literature 1 discloses a substrate to FPC (Flexible Printed Circuits) connector or a substrate to FFC (Flexible Flat Cable) connector.
FIG. 10 is an external perspective view of the connector disclosed in Patent Literature 1. The connector includes a plurality of contacts 2 electrically connected to conductor portions of FPC or FFC, insulating housing 3 storing the plurality of contacts 2, and lever 4 rotatably attached to housing 3.
Such a connector is demanded of narrowing the contact pitch so as to meet miniaturization of recent electronic devices. With a narrow-pitch connector, when the contacts are flexed in connecting to FPC or FFC, misalignment of the contacts occurs in the alignment direction of the contacts. This may result in short-circuiting because of the narrow contact pitch.
Accordingly, with the connector disclosed in Patent Literature 1, as shown in FIG. 10, grooves 61 storing the lower portions of contacts 2 and partition walls 62 partitioning adjacent contacts 2 are provided to housing 3. When the pitch of the connector is narrowed, the capacitance between terminals of adjacent contacts 2 increases, and in accordance therewith the impedance of adjacent contacts 2 reduces. This poses a problem of reflection or the like of signals, and an increase in loss. | {
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FIG. 1 illustrates a known winch 10 for retaining/tightening a cargo-retaining strap. The winch 10 comprises a steel frame 20 including a base 22 having first and second separate base plates 22a,22b that define locations L1,L2 for sliding receipt of a double-L track that is connected to or formed as a part of a cargo trailer or cargo bed, e.g., as part of a “flat-bed” trailer. First and second parallel legs 24a,24b are welded to the base 22 and cooperate with the base to define the frame 20 with an inverted U-shaped structure. A spool 26 is rotatably supported by and between the legs 24a,24b and comprises a slot 26a in which a cargo-retaining strap S is inserted and then wound around the spool for storage/use. The strap S is payed-out from the spool 26 as needed by counter-clockwise rotation of the spool, and retracted as needed by clockwise rotation of the spool 26. The spool 26 includes a driving head (not shown) that projects outwardly from sidewall 24b and that is engaged by a winch bar or other tool to rotate the spool. A ratchet wheel 28 is welded to the spool 26 and rotates therewith adjacent an outer face of sidewall 24a. A pawl 30 is pivotally secured to the sidewall 24a by a bolt, pin or other fastener 32 and pivots between a first position, as shown, where it engages the ratchet wheel 28 and prevents counter-clockwise rotation of the ratchet wheel 28 and spool 26 but allows clockwise rotation for strap tightening operations, and a second position, where it is disengaged from the ratchet wheel 28 to allow free rotation of the ratchet wheel 28 and spool 26 in either direction. The pawl 30 is normally positioned in its first position, as shown, by force of gravity and/or a biasing spring. The base 22 of the winch 10 can also be configured to mate slidably with a flanged side-rail of a cargo trailer or cargo bed, e.g., of a “flat-bed” trailer.
The winch 10 shown in FIG. 1 has been found to be sub-optimal for a variety of reasons. The frame 20, spool 26, ratchet wheel 28 and pawl 30 are defined from ferrous steel and are susceptible to corrosion and can weigh as much as 9 pounds (lbs.) or more. Furthermore, the frame 20, itself, comprises four separate steel pieces (base plates 22a,22b, sidewalls 24a,24b) that must be arranged properly and then welded together which increases assembly time and cost. Furthermore, the weld zones are susceptible to corrosion and/or failure.
FIG. 2 illustrates another known cargo-strap retaining winch 10′ that is structured similarly and functions identically to the winch 10. Unlike the winch 10, however, the winch 10′ comprises a one-piece frame 20′ defined from a steel plate that is bent into the required inverted U-shaped structure so as to comprise a base 22′ and first and second sidewalls 24a′,24b′. The locations L1′,L2′ for slidably mating with a double-L track of a flat-bed trailer or other cargo hauling structure as described above can be machined after the U-shaped frame 20′ is defined or can be defined in the frame-stock prior to the bending operation. The winch 10′ comprises a spool 26′, ratchet wheel 28′ and pawl 30′ that are identical in structure and function to those described above in connection with FIG. 1. The base 22′ of the winch 10′ can also be configured to mate slidably with a flanged side-rail of a cargo trailer or cargo bed, e.g., of a “flat-bed” trailer.
The winch 10′ represents an advantage over the winch 10 in terms of the simplified one-piece structure of the steel frame 20′ which eliminates all welding operations required to construct the frame 20 of the winch 10. Like the winch 10, however, the frame 20′, spool 26′, ratchet wheel 28′ and pawl 30′ of the winch 10′ are defined from ferrous steel and, as such, are susceptible to corrosion in a manner similar to the winch 10 and are high-weight, especially in light of the fact that a single trailer or other cargo bed will typically carry multiple winches, e.g., ten or more.
Another main disadvantage of the winch 10′, resulting from its one-piece U-shaped frame 20′, is that the base 22′ of the frame has a maximum possible width W1 which is only equal to the width W2 defined inclusively between the parallel sidewalls 24a′,24b′. This maximum possible width or “footprint” of the base 22′ has been found to be deficient for certain applications because the forces exerted on the winch 10′ by the strap S are undesirably concentrated within the maximum width W1 of the base. More particularly, the steel-framed winch 10′ is often mated with an aluminum structure such as a double-L track, a flanged side-rail, or the like of a cargo trailer, and this mismatch in material hardness and elasticity has been found to result in damage to the aluminum structure such as, e.g., bending, gouges, and tearing. The steel winch frame 20′ has a much higher hardness and lower elasticity as compared to the aluminum mounting structure of a flat-bed trailer or the like, and this leads to the noted damage to the aluminum structure. For example, 6061-T6 aluminum alloy has a Brinell hardness number (BHN) of 95, while Brinell hardness numbers for common steels, such as those used to manufacture the conventional winches 10,10′, vary between BHN=133 for A569 steel to BHN=250 for A514 and 100XF steels, and BHN=400 for AR400 steel. Furthermore, aluminum alloys commonly used in trailer and other cargo bed manufacturing such as, e.g., 6061-T6 extrusions, have a modulus of elasticity that only ⅓ of the modulus of elasticity of steel, i.e., the deflection of an aluminum structure will be three-times that of a similar steel structure. As such, it can be seen that use of steel winch structures 10,10′ on an aluminum trailer or cargo bed leads to an inherent mismatch in hardness and elasticity, with the common result being that the steel winch permanently damages the aluminum structure. Given the increasing popularity of flat-bed trailers and cargo beds defined entirely from aluminum or having aluminum siderails and/or winch tracks for mating with winches, a need has been identified for a new and improved winch compatible with these aluminum structures.
A further problem associated with use of steel winches 10,10′ on an aluminum alloy trailer or cargo bed is the resulting galvanic or “electrolysis” reaction that occurs between these dissimilar materials in the presence of an electrolyte, e.g., when wet by humidity or rain water. This reaction often causes the winches to become stuck on the winch track in a manner that prevents them from being easily moved to the required location to adjust the position of the cargo straps. Also, the electrolysis reaction speeds corrosion at the interface of the dissimilar metals due to ion exchange and can lead to severe pitting and failure.
New ice and snow control techniques have exacerbated the corrosion of conventional steel winches and also appear to act as a catalyst to the damaging electrolysis reaction between steel winches and aluminum alloy trailers and cargo beds. These new ice and snow control techniques include use of liquid compounds comprising magnesium chloride or calcium chloride that are many times more corrosive to steel as compared to “road salt” as we know it, e.g., sodium chloride. These new techniques are becoming more popular due to a cost advantage and are causing extensive damage to steel components of truck trailers. This phenomenon is documented in the article “Corrosion Explosion” appearing in the September 2004 issue of Trailer/Body Builders, pps. 38-45. As such, it is clear that corrosion of conventional steel winches 10,10′ exposed to these increasingly popular ice/snow control compounds will accelerate and render same unusable and/or unsafe.
Another main disadvantage associated with known winches 10,10′ is that the connection between the pawl 30,30′ and the sidewall 24a,24a′ frame by a bolt or other fastener 32 connected to the frame 20,20′ can be insufficient to hold the high-loads imposed on pawl 30,30′ through the ratchet wheel 28,28′. In particular, the fastener 32 is subjected to high bending and shearing forces that have been found to cause failure of the fastener with the result being an unconstrained ratchet wheel 28,28′ and strap S which can lead to loss of the cargo load. As such, improvements have been deemed desirable in connection with the connection of the pawl 30,30′ to the frame 20,20′ to improve safety.
With reference to FIGS. 2A,2B,2C, the steel frames 20,20′ of the winches 10,10′ lead to another safety deficiency in that the winches 10,10′ are often slidably receivable onto extruded aluminum winch tracks T1,T2,T3 such as double-L tracks defined from aluminum extrusions with a loose or uneven fit that results in gaps G1,G1,G3 between the track and the base 22,22′ of the winch frame. These gaps have been found to be highly undesirable in that forces exerted on the winch are not evenly distributed to the track and are thus more likely to damage the track, especially in light of the material mismatch issues noted above. In order for the winches 10,10′ to fit a double-L track with a more intimate fit, plates and other structures would have to be welded to the frames where needed, or added-thickness plates would need to be used to weld the frame or in the bended frame, and/or other time-consuming processing would be required, and this has not been done owing to economic constraints and/or because others have not recognized this problem of using steel winches on aluminum winch tracks. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The present invention relates to a still video apparatus which reproduces picture signals and/or sound signals recorded on a magnetic disc.
2. Description of the Related Art
Still video apparatuses, such as still video cameras or still video player's which record or reproduce an image of a picture and a sound as electrical signals (picture signals and sound signals) on and from a magnetic disc (video floppy), are available on the market.
In a known still video player, a picture signal for one frame (one picture plane) is recorded on one track (in case of field recording) or two tracks (in case of frame recording) of a magnetic disc by a magnetic head. Upon reproducing the recorded picture signals, every frame of recorded picture signals is reproduced from the predetermined one track or two tracks by the magnetic head. Similar to the picture signal, the sound signal for one track is recorded and reproduced, using the tracks for the picture signals. Namely, the magnetic head in the still video player is moved through a unit of displacement corresponding to one track or two tracks for each frame to reproduce the recorded picture signals for every frame or the recorded sound signals for every track in order to output the reproduced signals to respective external output terminals.
Upon copying the reproduced signals of the still video player onto another recording medium, such as a video tape, the picture signals and/or the sound signals are recorded on the video tape in such a way that the signals suddenly appear and disappear. Consequently, when the video tape is reproduced, a viewer tends to feel unnatural or strange.
Furthermore, the same is true when the sound signals recorded on another device, for example a CD (Compact Disc) player, are copied together with the picture signals recorded on the still video player on a video tape. | {
"pile_set_name": "USPTO Backgrounds"
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The present invention relates to internal combustion engines, and, more particularly, to exhaust gas recirculation systems used with internal combustion engines.
An exhaust gas recirculation (EGR) system is used for controlling the generation of undesirable pollutant gases and particulate matter in the operation of internal combustion engines. Such systems have proven particularly useful in internal combustion engines used in motor vehicles such as passenger cars, light duty trucks, and other on-road motor equipment. EGR systems primarily recirculate the exhaust gas by-products into the intake air supply of the internal combustion engine. The exhaust gas which is reintroduced to the engine cylinder reduces the concentration of oxygen therein, which in turn lowers the maximum combustion temperature within the cylinder and slows the chemical reaction of the combustion process, decreasing the formation of nitrous oxides (NoX). Furthermore, the exhaust gases typically contain unburned hydrocarbons which are burned on reintroduction it the engine cylinder, which further reduces the emission of exhaust gas by-products which would be emitted as undesirable pollutants from the internal combustion engine.
When utilizing EGR in turbocharged diesel engine, the exhaust gas to be recirculated is preferably removed upstream of the exhaust gas driven turbine associated with the turbocharger. In many EGR applications, the exhaust gas is diverted directly from the exhaust manifold. Likewise, the recirculated exhaust gas is preferably reintroduced to the intake air stream downstream of the compressor and air-to-air aftercooler (ATAAC). Reintroducing the exhaust gas downstream of the compressor and ATAAC is preferred due to the reliability and maintainability concerns that arise if the exhaust gas passes through the compressor and ATAAC. An example of such an EGR system is disclosed in U.S. Pat. No. 5,802,846 (Bailey), which is assigned to the assignee of the present invention.
A turbocharger as described above typically includes a turbine having a fixed geometry inlet which receives exhaust gas from the exhaust manifold for driving the turbine wheel in the turbine. Since the inlet has a fixed geometry, the rotational speed of the turbine wheel, and in turn the rotational speed of the compressor wheel, is principally dependent upon the flow characteristics of the exhaust gas from the exhaust manifold. The pressure ratio of the compressed combustion air outputted from the compressor thus may not be varied to any significant extent. This in turn may limit the effectiveness of mixing the compressed combustion air with the exhaust gas.
With conventional EGR systems as described above, the charged and cooled combustion air which is transported from the ATAAC is at a relatively high pressure as a result of th charging from the turbocharger. Since the exhaust gas is also typically inducted into the combustion air flow downstream of the ATAAC, conventional EGR systems are configured to allow the lower pressure exhaust gas to mix with the higher pressure combustion air. Such EGR systems may include a venturi section which induces the flow of exhaust gas into the flow of combustion air passing therethrough. An efficient venturi section is designed to xe2x80x9cpumpxe2x80x9d exhaust gas from a lower pressure exhaust manifold to a higher pressure intake manifold. However, because varying EGR rates are required throughout the engine speed and load range, a variable orifice venturi may be preferred. Such a variable orifice venturi is physically difficult and complex to design and manufacture. Accordingly, venturi systems including a fixed orifice venturi and a combustion air bypass circuit are favored. The bypass circuit consists of piping and a butterfly valve in a combustion air flow path. The butterfly valve is controllably actuated using an electronic controller which senses various parameters associated with operation of the engine.
With a venturi section as described above, the maximum flow velocity and minimum pressure of the combustion air flowing through the venturi section occurs within the venturi throat disposed upstream from the expansion section. The butterfly valve is used to control the flow of combustion air to the venturi throat, which in turn affects the flow velocity and vacuum pressure created therein. By varying the vacuum pressure, the amount of exhaust gas which is induced into the venturi throat of the venturi section can be varied. However, inducing the exhaust gas into the flow of combustion air in the venturi throat may affect the diffusion and pressure recovery of the mixture within the expansion section of the venturi.
The present invention is directed to overcoming one or more of the problems as set forth above.
In one aspect of the invention, an internal combustion engine is provided with an exhaust manifold, a turbocharger and a bypass venturi assembly. The turbocharger includes a turbine and a compressor, with the turbine having a variable geometry inlet coupled with the exhaust manifold, and the compressor having an outlet. The bypass venturi assembly includes a housing having an outlet, a combustion air inlet and an exhaust gas inlet. The combustion air inlet is coupled with the compressor outlet. The exhaust gas inlet is coupled with the exhaust manifold. A center piece is positioned within the housing and is in communication with the combustion air inlet. The center piece defines a combustion air bypass section therein. A combustion air bypass valve is positioned in association with the combustion air bypass section. The exhaust gas valve is positioned in association with the exhaust gas inlet. | {
"pile_set_name": "USPTO Backgrounds"
} |
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