A method and composition for treating arteriovenous malformations (AVMs), or abnormal vasculature in the body are provided. The method comprises introducing into the region of an AVM a composition comprising a nucleophilic component, such as a thiol, and a component containing a conjugated unsaturated bond, such as an acrylate through a catheter, whereby the composition crosslinks within the body to block or occlude the AVM.

Arteriovenous malformations (AVMs) are defects of the circulatory system that are generally believed to arise during embryonic or fetal development or soon after birth. They are comprised of snarled tangles of arteries and veins. The presence of an AVM disrupts the flow of blood through the body. Although AVMs can develop in many different sites, those located in the brain or spinal cord can have especially widespread effects on the body. AVMs of the brain or spinal cord (neurological AVMs) are believed to affect approximately 300,000 Americans. They occur in males and females of all racial or ethnic backgrounds at roughly equal rates.
Most people with neurological AVMs experience few, if any, significant symptoms, and the malformations tend to be discovered only incidentally, usually either at autopsy or during treatment for an unrelated disorder. But for about 12 percent of the affected population (about 36,000 of the estimated 300,000 Americans with AVMs), these abnormalities, also called lesions, cause symptoms that vary greatly in severity. For a small fraction of the individuals within this group, such symptoms are severe enough to become debilitating or even life-threatening. Each year about one percent of those with AVMs will die as a direct result of the lesions, largely due to brain hemorrhages.
Seizures and headaches are the most generalized symptoms of AVMs, but no particular type of seizure or headache pattern has been identified. Seizures can be partial or total, involving a loss of control over movement, convulsions, or a change in a person's level of consciousness. Headaches can vary greatly in frequency, duration, and intensity, sometimes becoming as severe as migraines. Sometimes a headache consistently affecting one side of the head may be closely linked to the site of an AVM. More frequently, however, the location of the pain is not specific to the lesion and may encompass most of the head.
AVMs also can cause a wide range of more specific neurological symptoms that vary from person to person, depending primarily upon the location of the AVM. Such symptoms may include muscle weakness or paralysis in one part of the body; a loss of coordination (ataxia) that can lead to such problems as gait disturbances; apraxia, or difficulties carrying out tasks that require planning; dizziness; visual disturbances such as a loss of part of the visual field; an inability to control eye movement; papilledema (swelling of a part of the optic nerve known as the optic disk); various problems using or understanding language (aphasia); abnormal sensations such as numbness, tingling, or spontaneous pain (paresthesia or dysesthesia); memory deficits; and mental confusion, hallucinations, or dementia. Researchers have recently uncovered evidence that AVMs may also cause subtle learning or behavioral disorders in some people during their childhood or adolescence, long before more obvious symptoms become evident.
One of the more distinctive signs indicating the presence of an AVM is an auditory phenomenon, or bruit: the rhythmic, whooshing sound caused by excessively rapid blood flow through the arteries and veins of an AVM. When audible to patients, bruit may compromise hearing, disturb sleep, or cause significant psychological distress.
Symptoms caused by AVMs can appear at any age, but because these abnormalities tend to result from a slow buildup of neurological damage over time they are most often noticed when people are in their twenties, thirties, or forties. If AVMs do not become symptomatic by the time people reach their late forties or early fifties, the lesions tend to remain stable and rarely produce symptoms. In women, pregnancy sometimes causes a sudden onset or worsening of symptoms, due to accompanying cardiovascular changes, especially increases in blood volume and blood pressure.
In contrast to the vast majority of neurological AVMs, one especially severe type causes symptoms to appear at, or very soon after, birth. Called a vein of Galen defect after the major blood vessel involved, this lesion is located deep inside the brain. It is frequently associated with hydrocephalus (swelling of the brain, often with visible enlargement of the head), swollen veins visible on the scalp, seizures, failure to thrive, and congestive heart failure. Children born with this condition who survive past infancy often remain developmentally impaired.
AVMs become symptomatic only when the damage they cause to the brain or spinal cord reaches a critical level. This is one of the reasons why a relatively small fraction of people with these lesions experiences significant health problems related to the condition. AVMs damage the brain or spinal cord through three basic mechanisms: by reducing the amount of oxygen reaching neurological tissues; by causing bleeding (hemorrhage) into surrounding tissues; and by compressing or displacing parts of the brain or spinal cord.
AVMs compromise oxygen delivery to the brain or spinal cord by altering normal patterns of blood flow. Arteries and veins are normally interconnected by a series of progressively smaller blood vessels that control and slow the rate of blood flow. Oxygen delivery to surrounding tissues takes place through the thin, porous walls of the smallest of these interconnecting vessels, known as capillaries, where the blood flows most slowly. The arteries and veins that make up AVMs, however, lack this intervening capillary network. Instead, arteries dump blood directly into veins through a passageway called a fistula. The flow rate is uncontrolled and extremely rapid, too rapid to allow oxygen to be dispersed to surrounding tissues. When starved of normal amounts of oxygen, the cells that make up these tissues begin to deteriorate, sometimes dying off completely.
This abnormally rapid rate of blood flow frequently causes blood pressure inside the vessels located in the central portion of an AVM directly adjacent to the fistula, the nidus, to rise to dangerously high levels. The arteries feeding blood into the lesion often become swollen and distorted; the veins that drain blood away from it often become abnormally constricted (a condition called stenosis). Moreover, the walls of the involved arteries and veins are often abnormally thin and weak. Aneurysms (balloon-like bulges in blood vessel walls that are susceptible to rupture) may develop in association with approximately half of all neurological AVMs due to this structural weakness.
Bleeding can result from this combination of high internal pressure and vessel wall weakness. Such hemorrhages are often microscopic in size, causing limited damage and few significant symptoms. Even many nonsymptomatic AVMs show evidence of past bleeding. But massive hemorrhages can occur if the physical stresses caused by extremely high blood pressure, rapid blood flow rates, and vessel wall weakness are great enough. If a large enough volume of blood escapes from a ruptured AVM into the surrounding brain, the result can be a catastrophic stroke. AVMs account for approximately two percent of all hemorrhagic strokes that occur each year.
Even in the absence of bleeding or significant oxygen depletion, large AVMs can damage the brain or spinal cord simply by their presence. They can range in size from a fraction of an inch to more than 2.5 inches in diameter, depending on the number and size of the blood vessels making up the lesion. The larger the lesion, the greater the amount of pressure it exerts on surrounding brain or spinal cord structures. The largest lesions may compress several inches of the spinal cord or distort the shape of an entire hemisphere of the brain. Such massive AVMs can constrict the flow of cerebrospinal fluid by distorting or closing the passageways and open chambers, or ventricles, inside the brain that allow this fluid to circulate freely. As cerebrospinal fluid accumulates, neurological tissues begin to swell, and in extreme cases, hydrocephalus results. This fluid buildup further increases the amount of pressure on fragile neurological structures, adding to the damage caused by the AVM itself.
AVMs can form virtually anywhere in the brain or spinal cord, wherever arteries and veins exist. Some are formed from blood vessels located in the dura mater or in the pia mater, the outermost and innermost, respectively, of the three membranes surrounding the brain and spinal cord. (The third membrane, called the arachnoid, lacks blood vessels.)
AVMs affecting the spinal cord are of two types, AVMs of the dura mater, which affect the function of the spinal cord by transmitting excess pressure to the venous system of the spinal cord; and AVMs of the spinal cord itself, which affect the function of the spinal cord by hemorrhage by reducing blood flow to the spinal cord, or by causing excess venous pressure. Spinal AVMs frequently cause attacks of sudden, severe back pain, often concentrated at the roots of nerve fibers where they exit the vertebrae; the pain is similar to that caused by a slipped disk. These lesions also can cause sensory disturbances, muscle weakness, or paralysis in the parts of the body served by the spinal cord or the damaged nerve fibers. Spinal cord injury by the AVM by either of the mechanisms described above can lead to degeneration of the nerve fibers within the spinal cord below the level of the lesion, causing widespread paralysis in parts of the body controlled by those nerve fibers.
Dural and pial AVMs can appear anywhere on the surface of the brain. Those located on the surface of the cerebral hemispheres exert pressure on the cerebral cortex. Depending on their location, these AVMs may damage portions of the cerebral cortex involved with thinking, speaking, understanding language, hearing, taste, touch, or initiating and controlling voluntary movements. AVMs located on the frontal lobe close to the optic nerve or on the occipital lobe, the rear portion of the cerebrum where images are processed, may cause a variety of visual disturbances.
AVMs also can form from blood vessels located deep inside the interior of the cerebrum. These AVMs may compromise the functions of three vital structures: the thalamus, which transmits nerve signals between the spinal cord and upper regions of the brain; the basal ganglia surrounding the thalamus, which coordinate complex movements; and the hippocampus, which plays a major role in memory.
AVMs can affect other parts of the brain besides the cerebrum. The hindbrain is formed from two major structures: the cerebellum, which is nestled under the rear portion of the cerebrum, and the brainstem, which serves as the bridge linking the upper portions of the brain with the spinal cord. These structures control finely coordinated movements, maintain balance, and regulate some functions of internal organs, including those of the heart and lungs. AVM damage to these parts of the hindbrain can result in dizziness, giddiness, vomiting, a loss of the ability to coordinate complex movements such as walking, uncontrollable muscle tremors, or disruptions in organ function (for example, heart failure).
The greatest potential danger posed by AVMs is hemorrhage. Researchers believe that each year between two and four percent of all AVMs hemorrhage. Most episodes of bleeding remain undetected at the time they occur because they are not severe enough to cause significant neurological damage. But massive, even fatal, bleeding episodes do occur. The present state of knowledge does not permit doctors to predict whether or not any particular person with an AVM will suffer an extensive hemorrhage. The lesions can remain stable or can suddenly begin to grow. In a few cases, they have been observed to regress spontaneously.
Besides AVMs, three other main types of vascular lesion can arise in the brain or spinal cord: cavernous malformations, capillary telangiectases, and venous malformations. These lesions may form virtually anywhere within the central nervous system, but unlike AVMs, they are not caused by high-velocity blood flow from arteries into veins. In contrast, cavernous malformations, telangiectases, and venous malformations are all low-flow lesions. Instead of a combination of arteries and veins, each one involves only one type of blood vessel. These lesions are less unstable than AVMs and do not pose the same relatively high risk of significant hemorrhage. In general, low-flow lesions tend to cause fewer troubling neurological symptoms and require less aggressive treatment than do AVMs.
Cavernous malformations are lesions formed from groups of tightly packed, abnormally thin-walled, small blood vessels that displace normal neurological tissue in the brain or spinal cord. The vessels are filled with slow-moving or stagnant blood that is usually clotted or in a state of decomposition. Like AVMs, cavernous malformations can range in size from a few fractions of an inch to several inches in diameter, depending on the number of blood vessels involved. Some people develop multiple lesions. Although cavernous malformations usually do not hemorrhage as severely as AVMs do, they sometimes leak blood into surrounding neurological tissues because the walls of the involved blood vessels are extremely fragile. Although they are often not as symptomatic as AVMs, cavernous malformations can cause seizures in some people. After AVMs, cavernous malformations are the type of vascular lesion most likely to require treatment.
Capillary telangiectases are lesions that consist of groups of abnormally swollen capillaries and usually measure less than an inch in diameter. Capillaries are the smallest of all blood vessels, with diameters smaller than that of a human hair; they have the capacity to transport only small quantities of blood, and blood flows through these vessels very slowly. Because of these factors, telangiectases rarely cause extensive damage to surrounding brain or spinal cord tissues. Any isolated hemorrhages that occur are microscopic in size. Thus, the lesions are usually benign. However, in some inherited disorders in which people develop large numbers of these lesions, telangiectases can contribute to the development of nonspecific neurological symptoms such as headaches or seizures.
Finally, venous malformations are lesions that consist of abnormally enlarged veins. The structural defect usually does not interfere with the function of the blood vessels, which is to drain oxygen-depleted blood away from the body's tissues and return it to the lungs and heart. Venous malformations rarely hemorrhage. As with telangiectases, most venous malformations do not produce symptoms, remain undetected, and follow a benign course.
Physicians now use an array of traditional and new imaging technologies to uncover the presence of AVMs. Angiography provides the most accurate pictures of blood vessel structure in AVMs. The technique requires injecting a special water-soluble dye, called a contrast agent, into an artery. The dye highlights the structure of blood vessels so that it can be recorded on conventional X-rays. Although angiography can record fine details of vascular lesions, the procedure is somewhat invasive and carries a slight risk of causing a stroke.
Two of the most frequently employed noninvasive imaging technologies used to detect AVMs are computed axial tomography (CT) and magnetic resonance imaging (MRI) scans. CT scans use X-rays to create a series of cross-sectional images of the head, brain, or spinal cord and are especially useful in revealing the presence of hemorrhage. MRI imaging, however, offers superior diagnostic information by using magnetic fields to detect subtle changes in neurological tissues. A recently developed application of MRI technology (magnetic resonance angiography or MRA) can record the pattern and velocity of blood flow through vascular lesions as well as the flow of cerebrospinal fluid throughout the brain and spinal cord. Both MRI and MRA can provide three-dimensional representations of AVMs by taking images from multiple angles.
Medication can often alleviate general symptoms such as headache, back pain, and seizures caused by AVMs and other vascular lesions. However, the definitive conventional treatment for AVMs is surgery.
The decision to perform surgery on any individual with an AVM requires a careful consideration of possible benefits versus risks. The natural history of an individual AVM is difficult to predict; however, left untreated, they have the potential of causing significant hemorrhage, which may result in serious neurological deficits or death. On the other hand, surgery on any part of the central nervous system carries its own risks as well; AVM surgery is associated with an estimated eight percent risk of serious complications or death. There is no easy formula that can allow physicians and their patients to reach a decision on the best course of therapyCCall therapeutic decisions must be made on a case-by-case basis.
Today, three surgical options exist for the treatment of AVMs: conventional surgery, radiosurgery, and endovascular embolization.
Conventional surgery involves entering the brain or spinal cord and removing the central portion of the AVM, including the fistula, while causing as little damage as possible to surrounding neurological structures. One description of this type of surgical treatment is described in Hillman and Pare, the disclosures of which are incorporated herein by reference. (Hillman, J.; "Population based analysis of arteriovenous malformation treatment" J. Neurosurg., 2001 October; 95(4):633 637; and Pare, M. C., Bojanowski, M., "Surgical Treatment of AVMs in Eloquent Zones of the Brain: Apropos of Eleven Cases", Ann. Chir., 1991; 45(9): 811 5.) This surgery is most appropriate when an AVM is located in a superficial portion of the brain or spinal cord and is relatively small in size. However, AVMs located deep inside the brain generally cannot be approached through conventional surgical techniques because there is too great a possibility that functionally important brain tissue will be damaged or destroyed.
Endovascular embolization and radiosurgery are less invasive than conventional surgery and offer safer treatment options for AVMs located deep inside the brain. Radiosurgery is the least invasive therapeutic approach. It involves aiming a beam of highly focused radiation directly on the AVM. The high dose of radiation damages the walls of the blood vessels making up the lesion. Radiosurgical techniques have been described by Wallace and Irie, the disclosures of which are incorporated herein by reference. (Wallace, R., Bourekas, E., "Brain Arteriovenous Malformations", Neuroimaging Clin. N. America, 1998 May; 8(2): 383 99; and Irie, K., Nagao, S., Honma, Y., Kunishio, K., Ogawa, T., Kawai, N. "Treatment of arteriovenous malformation of the brain preliminary experience", J. Clin. Neurosci., 2000 September; 7 Supple 1:24 29.) Over the course of the next several months, the irradiated vessels gradually degenerate and eventually close, leading to the resolution of the AVM.
Although radiosurgery is minimally invasive, it is not as effective as conventional surgery. Radiosurgery often has incomplete results, particularly when an AVM is large, and it poses the additional risk of radiation damage to surrounding normal tissues. Moreover, even when successful, complete obliteration of an AVM takes place over the course of many months following radiosurgery. During that period, the risk of hemorrhage is still present, and may in fact be higher.
The most promising technique is endovascular embolization. In this technique the surgeon guides a catheter though the arterial network until the tip reaches the site of the AVM. The surgeon then introduces a substance that will plug the malformation, correcting the abnormal pattern of blood flow. This process is known as embolization because it causes an embolus (a material which can obstruct or occlude blood flow) to travel through blood vessels, eventually becoming lodged in a vessel and obstructing blood flow. Embolization techniques are discussed generally by Jizong, Liu, Vernon, and Wallace the disclosures of which are incorporated herein by reference. (Jizong, Z., Shou, W., Jingsheng, L., Dali, S., Yuanli, Z., Yan, Z., "Combination of intraoperative embolisation with surgical resection for treatment of giant cerebral arteriovenous malformations", J. Clin. Neurosci., 2000 September; 7 Suppl. 1:54 59; Liu, H. M., Huang, Y. C., Wang, Y. H., "Embolization of cerebral arteriovenous malformations with n butyl 2 cyanoacrylate", J. Formos. Med. Addoc., 2000 December; 99(12):906 913; Vernon, B., et al., "Water Borne, in situ Cross Linked Biomaterials from Phase Segregated Precursors", Submitted Article to Journal of Biomedical Materials Research. February 2002; and Wallace, R., et al., "The Safety and Effectiveness of Brain AVM Embolization using Acrylic and Particles: The Experience of a Single Institution", Neurosurgery, 1995 October; 37(4); 606 18.)
The materials used to create an obstruction, occlusion or embolus in the center of an AVM include fast-drying biologically inert glues, fibered titanium coils, and tiny balloons. However, conventional embolization frequently proves incomplete or temporary because the materials being used degrade over time. Since embolization usually does not permanently obliterate the AVM, it is usually used only as an adjunct to surgery to reduce the blood flow through the AVM and make the surgery safer. Moreover, conventional AVM embolization materials (e.g. cyanoacrylates), stick to vessels. For example, cyanoacrylates used in known embolization materials have been known to glue catheters to vessels. These materials are also known to cause vessel cell wall damage or stress in AVM vasculature increasing the chance of incomplete occlusion, vessel rupture or hemorrhage.
To avoid this adhesion, other systems have also been investigated. Preformed polymers dissolved in water miscible organic solvents, such as Dimethyl Sulfoxide (DMSO), have been used for this application clinically. With these materials the polymer precipitates after injection into the vasculature as the solvent is replaced by water. Improvements have been made by replacing the DMSO with less toxic solvents such as N-methyl pyrrolidone (NMP). A further improvement would be the complete elimination of organic solvents with aqueous systems.
Recently, the advantages of waterborne, self-reactive systems have been recognized for this application. In fact two in situ gelling systems have been investigated recently. These are calcium alginate and thermally responsive polymers based on N-isopropylacrylamide. The calcium alginate systems developed by Becker et. al., the disclosure of which is incorporated herein by reference, proved to be biocompatible and mechanically stable; however, this procedure requires the simultaneous injection of two components delivered from two catheters position in separate locations in the vasculature: proximal and distal to the AVM or by double lumen catheters, restricting the viscosity (and thus gel strength) that can be delivered or increasing the catheter diameter and reducing the vessel accessibility. (Becker, T. et al., "Calcium Algenate Gel: A biocompatible and mechanically stable polymer for endovascular treatment", Journal of Biomedical Materials Research., Vol. 54 (2001), pp. 76 86.)
Accordingly, a need exists for improved embolization materials that would allow safer and more permanent minimally invasive relief of AVMs.

In situ gelling self-reactive materials for embolization


A mechanical lumbar support having an adjustment mechanism with a cam for effecting adjustment of the lumbar support member position. The cam is coupled to the lumbar support member through a linkage which enables the cam and actuating knob to be located at the optimum position for reaching and operating by a seat occupant, independent of the location of the lumbar support mechanism.

The present invention relates generally to a seat assembly having an adjustable lumbar support and in particular to an improved adjusting mechanism for the lumbar support.
Lumbar supports embodied in the vehicle seat assemblies are well known as illustrated by U.S. Pat. No. 4,725,095. This lumbar support is adjustable and is carried by a bar rotatably mounted to the seat frame for fore and aft movement as the bar is rotated. The adjusted position of the lumbar support member is controlled by a cam rotatably mounted to the seat back frame and engagable with a portion of the lumbar support bar. The cam serves to hold the lumbar support bar in a given position and to rotate the lumbar support bar upon rotation of the cam to adjust the lumbar support.
In order to package the cam and the adjustment mechanism within the seat back, the radius of the cam is limited by the thickness of the seat back. This necessitates the positioning of the cam and its actuating knob in a certain position relative to the lumbar support bar and the lumbar support member. As a result, there is little flexibility in the placement of the actuating knob used to turn the cam. The lumbar support member is naturally positioned adjacent the lumbar region of a seat occupant. The required position of the handle for packaging and proper operation of the mechanism is not necessarily in the best location for reaching and operating by a seat occupant while seated. Typically the position of the actuating knob is higher along the side of the seat back than
It is an object of the present invention therefore to provide an adjustment mechanism for the lumbar support member that enables the adjustment knob to be placed at a location that is easily reached by a seat occupant.
It is a further object of the invention to provide such a mechanism that continues to use a rotating cam for simplicity.
It is a feature of the present invention that the adjustment mechanism includes a link having a cam follower at one end for engagement with the cam and connected at the other end to the lumbar support bar. With such a mechanism, the cam and adjustment knob can be located where desired and the link made of whatever length is necessary to couple the lumbar support bar to the cam.
It is a further feature of the adjustment mechanism of the present invention that in a preferred embodiment, the cam control surface does not include stopping detents to hold the cam and lumbar support member in position but rather the control surface is smooth. Stop detents are provided elsewhere on the cam and are engagable with a spring biased plunger to hold the cam and the lumbar support member in position. By providing stop detents separate from the control surface, the pressure acting upon the lumbar support member will have a limited effect on the force required on the actuating knob to adjust the lumbar support. As a result, the adjustment mechanism is smoother and more consistent in its operation.
Further objects, features and advantages of the invention will become apparent from a consideration of the following description and the appended claims when taken in connection with the accompanying drawings.

Seat assembly with lumbar support mechanism


Live migration can be performed for a process executing on an allocated resource for an application session. During a session it might be determined that it is necessary, or would at least be advantageous, to migrate the process to different resource capacity. New capacity such as a new computing instance can be identified, and synchronized with a current instance to reflect current state information. This can include obtaining state data from a serialized file or transaction log, among other such options. The client devices on the session can be caused to connect or direct state data to the new instance, and when ready the new instance can be responsible for the process, such as by taking over as the application server for the session. Once the client devices are utilizing the new instance, the process can be terminated on the old instance and the instance destroyed or reallocated.

The widespread adoption of a variety of computing devices has resulted in a corresponding increase in the variety of applications available to users. For gaming applications, many of these games enable users to engage in online multiplayer games, which may be hosted by a central gaming server. The amount of resource capacity needed to host the variety of games has become significant, such that many providers use third party resource providers to host the games. While such an approach prevents the game developers from having to purchase and manage a large fleet of resources, the need to purchase capacity from these providers can still be significant. For large games that require significant capacity, this can still be too expensive for the developers to utilize for an extended period of time, or without charging excess fees to the players of those games. Even if capacity is obtained that is reasonable at one point in time, conditions may change that cause the obtained capacity to be less than optimal for the current allocation.


Systems and methods for generating, adjusting and/or evolving a visual personification of an AI interface for an AI application are provided. More specifically, the visual personification of the AI interface is generated, adjusted, and/or evolved based on one or more user inputs and/or the evaluation of other known user data. Accordingly, the generated, adjusted and/or evolved visual personification of an AI interface based on the user increases engagement, trust, and/or emotional connection with the user without requiring any AI interface setting changes by the user.

Language understanding systems, personal digital assistants, agents and artificial intelligence are changing the way users interact with computers. Developers of computers, web services, and/or applications are always trying to improve the interactions between humans and computers. For example, developers may look for new ways to humanize different aspects of the interactions between humans and computers.
It is with respect to these and other general considerations that aspects disclosed herein have been made. Also, although relatively specific problems may be discussed, it should be understood that the aspects should not be limited to solving the specific problems identified in the background or elsewhere in this disclosure.

Systems and methods for artificial intelligence interface generation, evolution, and/or adjustment


A phosphorus compound of formula (1):

(1) Field of the Invention
The invention relates to a phosphorus compound useful as a ligand of a metal catalyst and a production process thereof.
(2) Description of the Related Art
Conventionally, many reports have been published on transition metal complexes usable as a catalyst for an asymmetric reaction such as asymmetric hydrogenation reaction, asymmetric isomerization reaction, and asymmetric hydrosilylation reaction. Especially, complexes containing a transition metal such as ruthenium, rhodium, iridium, palladium, or the like and an optically active phosphine compound coordinated with the metal have widely been known as a high performance catalyst for an asymmetric synthesis reaction. Among such optically active phosphine compounds, an optically active biaryl phosphine compound with axial asymmetry is useful as an optically active ligand of an asymmetric reaction catalyst (see, for example, Tetrahedron, 2005, Vol. 61, 5405-5432). Many of the processes to synthesize such an optically active biaryl compound involve homo- or cross-coupling of two aryl units, and require optical resolution to obtain an optically active substance after the coupling (see, for example, JP-A-2000-16997 and JP-A-10-182678). To synthesize an optically active biaryl phosphine compound, it is required to introduce a phosphorus atom site into the biaryl skeleton before or after the synthesis of the biaryl compound by the above-mentioned homo- or cross-coupling (see, for example, JP-A-10-182678 and JP-T-10-501234). On the other hand, recently, as a new technique for synthesizing an optically active biaryl compound, a technique involving enantio-selective [2+2+2] cycloaddition reaction using alkynes has also been developed (Organic Letters, 2006, Vol. 8, 3489-3492).

Optically active biaryl phosphorus compound and production process thereof

Abstract: A phosphorus compound of formula (1):

Abstract: wherein R1 denotes a hydrogen atom or a hydroxy protective group; R2 denotes a group defined by the following formula (R2-1) or (R2-2); R3, R4, R5, and R6 may be the same or different and independently denote a hydrogen atom, an alkyl group, an alkoxy group, an acyloxy group, a halogen atom, a haloalkyl group, or a dialkylamino group; two among R3, R4, R5, and R6 may form an aromatic ring optionally having a substituent group, and two among R3, R4, R5, and R6 may form a methylene chain optionally having a substituent group or a (poly)methylenedioxy group optionally having a substituent group:

Abstract: wherein (R2-1) and (R2-2), R7 denotes an alkyl group, a cycloalkyl group, an aryl group, an alkoxy group, or an aryloxy group; R8 and R9 independently denote a hydrogen atom, an alkyl group, or an aryl group; z denotes a divalent group; and a denotes an integer of 0 or 1.

National University Corporation Tokyo University of Agriculture and technology


A refillable cosmetic compact with a product base insert repositionable in relation to a base structure between an engaged configuration and a disengaged configuration. An actuation opening through the base structure permits a pressing of a release button of the product base insert to induce the product base insert from the engaged to the disengaged configuration. Resiliently deflectable catch members project longitudinally from either or both of the base structure and the product base insert. Converging deflection surfaces engage the catch members as the product base insert is repositioned from the disengaged configuration to the engaged configuration to deflect the catch members laterally inwardly to retain a cosmetic pan and to permit a deflection of the catch members laterally outwardly as the product base insert is repositioned from the engaged configuration to the disengaged configuration to release or receive a cosmetic pan.

Compacts for solid or semi-solid cosmetic products typically have a base structure and a cover. One or more inner volumes or cavities are disposed in the base structure for receiving and retaining a volume of cosmetic. The solid or semi-solid cosmetic product may, by way of example and not limitation, be pressed or caste powder, semi-solid paste, or a cosmetic cake. Such materials could, again by way of illustration, could comprise blush powder, skin foundation cosmetic, lip cosmetic, eye shadow, or another cosmetic product. The cosmetic product is often disposed in a shallow plastic or metal pan to be retained in the inner volume of the base structure.
It is important that the cosmetic product be securely retained in the cavity of the cosmetic compact, particularly since the compact is likely to be subjected to jostling and impacts not only during use but also while it is transported, such as within a pocket, a purse, or a travel bag. It is likewise important that cosmetic compacts be efficiently arranged so that available space is maximized. Furthermore, in the competitive field of cosmetic packaging, it is a common goal to develop packaging demonstrating increased efficiencies in manufacturing and material requirements. Perceived elegance and luxury in operation are also long-recognized goals in the cosmetics industry.
Meanwhile, there is a need to permit the cosmetic pan to be selectively removed from its position within the cavity of the cosmetic compact. For instance, when a volume of cosmetic within a pan is nearly or completely gone, it is desirable to be able to replace the pan within the compact. In other circumstances, a user may wish to switch the cosmetic pan to one containing a different color or type of cosmetic.
There have been multiple attempts to provide a cosmetic compact capable of securely retaining a cosmetic pan for usage and transport while permitting the selective removal and replacement thereof. In certain prior art cosmetic compacts, a user must attempt to pry the cosmetic pan from its position within the compact in a practice prone to messiness, inadvertent dropping, and general inconvenience. In other cosmetic compacts, such as in that disclosed by International Publication No. WO86/00600 of Strnad, a magnet is required for releasably retaining a cosmetic pan, and the cosmetic pan must include ferrous metal. Still further, to accomplish the somewhat competing goals of achieving secure retention while permitting ready removal and replacement of cosmetic pans, many cosmetic compacts of the prior art have been markedly complex in structure and operation.
The present inventors have thus recognized the need for a cosmetic compact of efficient construction and elegant operation that is capable of securely retaining a volume of cosmetic material while permitting the cosmetic material to be selectively removed from the cosmetic compact in a convenient manner.


An antitheft device is provided, whereby a person who attempts to commit a theft of a vehicle can be captured, having an improved crime prevention performance to thefts of vehicles, electrical equipment mounted on vehicles, money and articles left inside vehicles and the like. The antitheft device includes an expansible body system to expand an expansible body for blocking the motion of an intruder in a prescribed space inside a vehicle, which emits a substance to be a base of foaming polystyrene inside the vehicle and applies steam to the substance so that the foaming polystyrene blocks the motion of an intruder, when the presence of the intruder inside the vehicle is detected.

In Japan, both the number of cases and the incidence of theft, such as stealing cars and breaking into cars, are lower than in Europe and America, but are trending upward, which is an object of public concern. Therefore, in recent years, various antitheft devices for preventing car theft have been invented. Examples include devices which sound an alarm such as a siren, or turn on a lamp and the like, if a door lock of a car is broken or window glass such as front, rear, or side window glass is broken.
Sounding an alarm or turning on a lamp enables those around the car to find a car theft being committed, so that it appears to become possible to minimize the damage.
However, when there is no one around the car, or an intruder into the car does not mind the siren blowing or the lamp shining at all, there is a high possibility of the electrical equipment mounted on the car, or money and articles left inside the car being stolen, even if it is possible to prevent the car itself from being stolen.
As one method for solving this problem, making some kind of attack on a person who attempts to commit a car theft for preventing the theft is being considered. However, since car theft ranges in level from extremely vicious crimes to minor offenses, to make the same attack equally on any person that is attempting to commit a theft might become an issue in some cases. In addition, excessive attacks might only stimulate thieves.


A system for cooling, heating and fire-protecting an enclosure or dwelling, consisting of six principal entities acting in cooperation. The first is an expansive system of wide, shallow ducting installed just outboard and against the innermost wall layers of the peripheral walls, ceiling and at times, the floor, thermally intimate but physically isolated from the interior volume of the enclosure. The second is an evaporatively-cooled air source, supplying the duct system, which cools the innermost wall layers and in turn, the interior volume, by radiation and convection. The third entity, being an encompassing layer of efficient insulation, just outboard of the ducting and within the enclosure, biasing the cooling and heating action to the interior volume. The fourth is a network of hot-water circulating tubes, lying within, or adjacent to said cooling ducts, and against the innermost wall layer, or inboard plate thereof. The fifth entity utilizes the in-place source of water in the peripheral walls and ceiling, for incorporation of heat-activated fire a suppression units therein, spraying into both, rooms and the duct system, as well. The last (sixth) entity provides for humidity control, convection, and `sensible` cooling of infiltration air by a limited size, integral air-conditioner and independent air circulation fans within the interior volume of the enclosure or dwelling.

1. Field of the Invention
This invention relates to the field of air conditioning and heating and more specifically, an environmental management system (Dynamic Insulation) for dwellings, fixed and mobile, storehouses, containers and rigid or flexible temporary structures, involving efficient passive insulation, exterior to primary evaporative-para-transfer-cooling of walls with secondary, `sensible` air conditioning and air circulation means, water-based radiant heating and water-spray fire-suppression in the interior volume, all working together synergistically for greatest cost-benefit, safety and comfort.
2. Description of Prior Art
The principle of cooling an air stream by evaporative-humidification for the purpose of reducing the temperature within an enclosed space, or volume, such as a dwelling, is well established. Devices for accomplishing this, with improvements through the years, have resulted in an array of methods with varying degrees of success, depending upon their cost, complexities and effective comfort, the most comfortable being those which provide cooling without the introduction of highly humid air into the interior volume and to occupants.
Unfortunately, systems developed to do this have resorted to external heat exchangers requiring multiple fans exposed to the exterior which are more costly, complex and bulky, wasting energy and water in the process.
Adding a small window or through-the-wall, self-contained mechanical air conditioner to a central evaporatively-cooled air system is, sometimes a compromise solution, which costs less to buy and operate than a central mechanical air conditioner system with distributed outlets and offers some added comfort in the room or space allotted to the `sensible` cooler. However, some prior art teaches a method of sending evaporatively-cooled air to the outside of an enclosure in a film, or through channels formed by support beams or studs spaced between the outside layer and the innermost layer of walls and ceiling, or roof, without contact or mixing with the interior volume of sensibly-cooled air. In particular, in U.S. Pat. No. 2,637,181, Schramm describes a system involving an evaporatively-cooled air stream flowing from a roof unit into an attic space, for cooling said space above the presumably non-insulated ceiling and then exiting through short, broad elbow-shaped ducts, out of said attic and then downward outside, to direct flow alongside the exterior wall surfaces as a shield against outside thermal influx. No evaporatively-cooled air is introduced to the interior volume of the dwelling below the ceiling level.
In U.S. Pat. No. 3,964,268, DiPeri teaches a method, wherein an exterior heat-exchange unit uses an evaporatively-cooled airstream to remove heat from a second, ambient or `dry` air stream without imparting any added humidity to said second stream, that is, `sensibly` cooling it and using it to condition the interior volume of a dwelling. The heat drawn out therefrom, is removed by vaporizing into the first air stream, liquid water, dripped onto an array of parallel tubes, wrapped with gauze for water retention, over which the first air stream flows and then discharges onto the exterior of the roof surface or through channeling formed by the double-layer roof/ceiling construction of conventional industrial buildings. The saturation level of the humidified first stream is rarely complete, being on the average, from 70% to 80%, as are most conventional one-stage coolers of simple design, using the wetted pad principle. Any increase in saturation over that stated would generally require a spray, or mist introduction, or special mixing techniques, to gain excess water suspensions, which then could continue to evaporatively cool, down-stream. Any limitation in saturation severely reduces the ability of the first stream exhaust to continue to pull heat from the outside environment or the roof and wall channels, by latent heat of evaporation, i.e., `drying`, since the discharged air having no excess un-evaporated water therein, can only cool the area by co-mingling and averaging its kinetic energy with that of the immediate environment's higher kinetic energy.
The splitting of heat energy taken up by evaporating water into the first stream, and sharing between the second stream `sensible` flow and the first stream's exterior "barrier flow", compromises the ability of the first steam to remove as much heat from the roof exterior, or peripheral walls, as it might, having already removed significant heat from the second stream and carried it along as `gaseous` water vapor, so to speak. The first stream, therefore, cannot reach as low a temperature entering, say, the confinement of the walls, or ceiling, as it could if the flow had not passed through a prior heat exchanger at all. It, therefore becomes an ancillary or "secondary" cooling method only, relying on `sensibly` cooled air for "primary" interior conditioning . A "primary" evaporative cooling method would require a cool layer to be maintained as close to the interior volume as possible, ready to remove heat from both the innermost wall layers themselves and any influx of heat from the outboard side, as well. The DiPeri invention in essence, teaches the replacement, of insulation with a moving blanket of cooler, but less than saturated air, while the present invention calls for an insulation layer of low thermal conductivity and high radiation reflectivity in both directions, as well as low convection values, to be placed between the exterior environment and the duct layer. This, with the addition of `excess` moisture into the evaporatively-cooled air stream by mist means, increases the cooling potential of the system to qualify it as a "primary" means of heat rejection for the interior volume of an enclosure, with `sensibly` cooled air being independently administered as a "secondary" cooling means.
In prior teachings, wherein evaporative-cooling is used for conditioning the interior volume, the introduction of water is usually controlled by means of a wetted surface exposed to an air stream, co-mixing so as to present as large a surface area as possible and means to recirculate the water for continued presentation, with conservation in mind. However, a presentation of water sometimes is through mist or spray means as taught in U.S. Pat. No. 4,308,222, Goettel, et al., wherein an excess of water is sprayed into the air, counter to the air flow and allowed to evaporate downstream, in two tandem expansion chambers, with means to recover excess water and subsequently drain it away, the realization being that excess moisture, if allowed to enter the ducting and interior volume of the dwelling or enclosure will cause increased corrosion to ducting and impinge upon occupants, furniture and paper goods, etc., causing discomfort and possible damage thereto.
In the present invention, excess water in the airstream is actually exploited for its ability to evaporate within water and corrosion-proof ducting downstream, for increased cooling capacity throughout the ducting area surrounding the innermost peripheral walls, ceiling (and floor) of the interior volume of a dwelling, or enclosure.

Dynamic insulation and air conditioning and radiant heating system


The present invention provides a piezoelectric thin film element with superior piezoelectric properties in which the condition of the crystal of the piezoelectric thin film is appropriately controlled, and a manufacturing method thereof, as well as a inkjet recording head, inkjet printer, or other liquid ejecting apparatus employing the same. The piezoelectric thin film element 40 comprises a top electrode 44, a bottom electrode 42, and a piezoelectric thin film 43 formed between the top electrode 44 and the bottom electrode 42, wherein the piezoelectric thin film 43 is structured so as to comprise a first layer 431 located nearest to the bottom electrode and second layers (433–436) that are located nearer to the top electrode than the first layer and that each have a thickness greater than that of the first layer 431.

1. Field of the Invention
The present invention relates to a piezoelectric thin film element, a manufacturing method thereof, and a liquid ejecting head and liquid ejecting apparatus employing the same, and more particularly to a piezoelectric thin film element or the like with superior piezoelectric properties and productivity.
2. Description of the Related Art
Piezoelectric thin film elements that employ piezoelectric thin films that contain crystals typified by PZT (lead zirconate titanate; Pb(ZrxTi1-x)O3) have functions such as spontaneous polarization, high permittivity, electro-optic effects, piezoelectric effects, and pyroelectric effects, and are applied in extensive device development.
A piezoelectric thin film element is structured by sequentially stacking a substrate, a diaphragm, a bottom electrode, a piezoelectric thin film, and a top electrode. Since piezoelectric properties of a piezoelectric thin film vary according to the condition of the crystal (such as the orientation of the crystal that makes up the film), the condition of the crystal must be controlled when the piezoelectric thin film is formed.
Possible methods of forming a piezoelectric thin film include sputtering, sol-gel processes, CVD, laser ablation, and the like, but sol-gel processes, which form a film by sol application, drying, pyrolyzing and annealing, are superior for controlling the condition of the crystal.
Such piezoelectric thin films are known to have superior piezoelectric properties when comprising a PZT fine crystal film with a high degree of orientation.
In conventional practice, PZT crystal films composed of stacked material comprising a plurality of thin layers have been suggested for obtaining a PZT fine crystal film.
However, using stacked material comprising a plurality of thin layers for the PZT crystal film has disadvantages in that the number of layers must be increased in order to obtain the desired thickness, increasing the number of processes for forming the layers and decreasing productivity. Due to the increase in the number or processes for forming the layers, there is also a possibility that chances will increase for contaminants such as waste to get mixed inside the film, causing the risk of reduced reliability for the piezoelectric thin film element.

Method of manufacturing a piezoelectric thin film element


A semiconductor-insulator-semiconductor (SIS) structure diode device for providing fast optoelectronic switching with stimulated emission. The device includes a substrate which has a buffer layer disposed on top thereof. An n-type cladding layer is disposed on top of the buffer layer. An undoped i-region is disposed on top of the buffer layer. The i-region includes at least one quantum well disposed between two waveguide layers. A lightly doped p-type cladding layer is disposed on top of the i-region. A contact layer is further disposed on top of the p-type cladding layer. First and second contact terminals are included for providing a two-terminal device. The diode advantageously provides good lasing performance, significant negative differential resistance and strong light sensitivity. In an alternate embodiment, a third terminal is connected to the undoped i-region to thereby form a three terminal device.

1. Technical Field
This invention relates to a semiconductor-insulator-semiconductor (SIS) structure diode and, more particularly, to novel quantum well optoelectronic switching devices with stimulated emission capabilities.
2. Discussion
Microwave semiconductor devices are generally used for generation, amplification, detection and control of high frequency electromagnetic energy. However, the usefulness of conventional semiconductor devices at relatively high frequencies is severely limited by high frequency effects. The use of III-V compound semiconductors such as gallium arsenide (GaAs) or indium phosphate (InP) rather than silicon has provided a tremendous improvement because the mobilities of electrons of these materials are several times as high- as silicon which leads to lower series resistance.
Various optoelectronic switching devices exhibiting stimulated emission have been developed. Such devices have become attractive due to their potential applications in microwave generation, high speed logic switches, optical interconnects for integrated circuits, optical computing systems and optoelectronic integrated circuits (OEICs). Double barrier resonant tunneling diodes have been integrated monolithically with a quantum well (QW) laser to form an optical bistable device. Double heterostructure optoelectronic switching (DOES) devices incorporated with a single quantum well laser and vertical-to-surface transmission electrophotonic (VSTEP) devices have also been demonstrated as lasers to achieve stimulated emissions. However, due to the presence of the pn junction, the efficiency and the power of these devices have been found to be limited. In addition, most of the optoelectronic switching device structures are not compatible with OEICs, and thus cannot be easily integrated into OEICs.
Thus, it would be desirable to have an optoelectronic switching device which has a potential for faster optoelectronic switching. In addition, it is desirable to have such a device which exhibits a good lasing performance, significant negative differential resistance and a strong light sensitivity. Furthermore, it is desirable to have such a device which is compatible with state-of-the-art OEICs.

Quantum well switching device with stimulated emission capabilities


Disclosed is an elongate peg, preferably of wood, which has lips or shoulders generally perpendicular to the length of the peg body and adjacent opposite ends. The lips or shoulders are on opposite sides of the peg body. The peg is used to tighten or tension the vertical lacing in "bongo" type drums by contacting adjacent pairs of vertical lacing with the peg whereby each lip is in contact with one of the adjacent pair of vertical lacing so that when the peg is flipped generally horizontal end forward, a twist is formed in the lacing pair at one end of the peg held by the lip while the other end of the peg is forcibly held against the drum shell by the force in the twist. In a preferred aspect, the drum profile is such that the spacing between the vertical lacing and the drum shell is increased slightly to facilitate more easily the flipping of the peg but still retain a peg end in forceable contact with the shell once flipped.

Drums, colloquially known as "bongo" drums come in various styles. Two in particular which are common are descendants of African drums known as ASHIKOS and DJEMBES. The wooden shells of these drums are similar in shape and size, but not exactly the same as, other drums manufactured by many other companies.
Traditional ASHIKOS and DJEMBES drums function by sketching an animal hide or skin over one end of the wooden shell. In many cases (but not all) a system, which is adjustable, is used to create tension on the skin. The common tightening systems were the Traditional African Weave (T.A.W.) and a mechanical nut and bolt system.
The wooden shells of the ASHIKOS and DJEMBES based drums include at least a tapered lower portion or some section or area narrower than the top. The T.A.W. system utilizes three steel rings of two different diameters or sizes. Two of the rings, including the smaller diameter ring and one of the larger diameter rings, have a plurality of double-hitches or knots with interconnecting rope sections peripherally around the rings and are commonly known as "roped rings". The other larger diameter ring is known as an "unroped ring". The smaller sized roped ring slides over the narrower end of the drum shell and is sized relative to the shell so as to stop about half way up the height of the shell due to the shell's taper. The skin is wedged down between the top two rings with the roped ring on top. A single length of rope is then vertically laced between the ropes of the two roped rings to stretch and tension the skin over the top of the drum shell. Tensioning of the skin is conventionally done by weaving the excess rope from the vertical lacing through the vertical lacing in such fashion as to create a twist in the vertical lacing. The twist causes the vertical lacing to place the skin under more tension and effectively provide for the tuning of the drum.
The tensioning of the skin by this weaving technique is time consuming and requires skills which are difficult to teach. Accordingly, it would be advantageous to have some means to facilitate the tensioning of the skin which requires less time and less skill, and yet produces a fine product.

Peg device for use in tensioning drum skins and to novel shaped drums using the peg device


The present invention provides a traction device for a terrain engaging element. The traction device defines a stud having a head portion and a shank portion extending from the head portion and adapted to be secured into the terrain engaging element. A plurality of spherical carbide pellets are bonded together on and to surfaces of the head. The carbide pellets are provided in multiple layers extending across the head surface. The carbide pellets are provided in a stacked relationship to each other so that during use the carbide pellets are capable of being individually dislodged to reveal a carbide pellet of an underlying layer.

Examples of footwear suitable for outdoor use over adverse terrain such as snow, ice, mud, rocks, etc., are well known. Accessory devices for such footwear are also known. Hobnails, screws and studs are examples of such accessory devices. Each of these accessory devices include significant limitations of use. Hobnails have been inserted into the soles of shoes or boots to prevent wear and improve traction. Hobnails are typically short nails which tend to quickly wear on rock surfaces and are often inadvertently removed during use in mud, moss, rocks and ice. Metal screws have also been used to improve traction in footwear. In a typical application, one or more metal screws are secured into a shoe sole. Metal screws typically wear relatively quickly and, once worn, tend to slide on surfaces leading to a decrease in traction across certain flat surfaces such as concrete floors, etc. Other examples of footwear suitable for outdoor use in water and rocks include felt and treaded rubber soles.
Tire studs, which may include carbide or porcelain studs, have been used to improve the traction of vehicles. In a typical application, a single generally cylindrical carbide element is secured within an aluminum housing. Porcelain studs are relatively brittle and may be damaged by ground impact. One limitation of tires studs is the propensity of the carbide or porcelain stud element to round over. In certain applications, the rounded-over element may lead to a decrease in traction, such as on concrete floors or other flat surfaces.
U.S. Pat. No. 5,897,177 to Bergstrom discloses a stud having a multifaceted surface for use on a tread element. The stud includes a body portion including a head and an elongated shank portion extending from the head. A mound of shard-like particles of a hard and durable material is bound together on and to the head of the stud such that the mound of particles has a multifaceted surface including multiple points which can engage the terrain. One limitation of the studs according to Bergstrom is the tendency of the particles to fracture during use due to the relatively few contact points defined by the sharp edges of the particles. The carbide fractures are typically uncontrolled and relatively large portions of the particles may be shed during a fracture. Because of the tendency of shedding relatively large particle portions, Bergstrom's device is believed to wear relatively quickly leading to poor economy of use. Additionally, the sharp edges of these studs may have a tendency to catch or snag on certain surfaces, such as carpet, which may lead to a tripping hazard. Furthermore, the relatively few contact points result in high contact forces which may be damaging to certain floors, such as wood and tile floors.
Accordingly, despite the attempts to develop improved devices for improving traction on adverse surfaces, there remains a need for an improved stud-style carbide traction device.

Carbide studs for stability and motive traction of footwear


Various methods are described for forming threads in a workpiece, and particularly for controlling and/or monitoring threading of workpieces. Also described are tools and a system used in performing the methods.

During conventional use of power drives, and specifically while operating a pipe threading tool (see, e.g., U.S. Pat. Nos. 6,502,041; 8,804,104; 9,267,900, and US Published Application 2020/0189017), a user must closely watch the end of a length of pipe or other workpiece as it is being threaded, to avoid problems arising when the pipe-threading operation is stopped too early or too late. When the end of the pipe aligns with an end of a fixed die, the thread is completed according to applicable industry standards, as desired, and operation of the tool can be stopped. However, it is often difficult for an operator to see the end of the length of pipe during the die head rotation of the thread-cutting component of the tool. Thus, uncertainty can result when the operator of the tool discontinues threading, unless monitored. Moreover, less skilled operators are often used to operate the tool. Such users often may not recognize thread completion and thus may not be able to adequately monitor.
Power drives, and especially hand-held power drives, are capable of exerting a significant amount of torque ordinarily required to thread pipe or drive other functions. Whether use of a support arm to counteract such torque is either mandated by industry or governmental standards, or merely recommended (depending on application), certain users choose not to use the support arm but, instead, manually achieve such required torque by manually holding the tool in-place. (See, e.g., US 2015/0086287.) If the tool slips from such users' grip, or the reaction force exceeds such users' physical capabilities, the tool may rotate relative to the workpiece uncontrollably. Similarly, poor attachment of the support arm can cause the support arm to slip and thus cause the tool to rotate relative to the pipe. In either of these scenarios, the torque of the tool can be transmitted to such users without warning.
Accordingly, in view of these and other concerns, a need exists for new methods for controlling threading of pipe or other workpieces.

Algorithms and methods for controlling threading of pipe


A method comprising the steps of performing a linear prediction analysis of a speech signal digitized in a series of frames divided into sub-frames, in order to determine the parameters of a short-term synthesis filter; carrying out an open loop analysis to detect voiced signal frames and determine, for each voice frame, a degree of signal voicing and a long-term prediction delay search interval containing a number of delays depending on the degree of voicing; carrying out a closed-loop predictive analysis of the speech signal to select, for at least some sub-frames of the voiced frames, a long-term prediction delay contained in the search interval and constituting a long-term synthesis filter parameter; and determining a stochastic excitation for each sub-frame, to minimize a perceptually weighted deviation between the speech signal and the stochastic excitation filtered by the long-term and short-term synthesis filters.

The present invention relates to analysis-by-synthesis speech coding.
The applicant company has particularly described such speech coders, which it has developed, in its European patent applications 0 195 487, 0 347 307 and 0 469 997.
In an analysis-by-synthesis speech coder, linear prediction of the speech signal is performed in order to obtain the coefficients of a short-term synthesis filter modelling the transfer function of the vocal tract. These coefficients are passed to the decoder, as well as parameters characterising an excitation to be applied to the short-term synthesis filter. In the majority of present-day coders, the longer-term correlations of the speech signal are also sought in order to characterise a long-term synthesis filter taking account of the pitch of the speech. When the signal is voiced, the excitation in fact includes a predictable component which can be represented by the past excitation, delayed by TP samples of the speech signal and subjected to a gain g.sub.p. The long-term synthesis filter, also reconstituted at the decoder, then has a transfer function of the form 1/B(z) with B(z)=1-g.sub.p.z.sup.-TP. The remaining, unpredictable part of the excitation is called stochastic excitation. In the coders known as CELP ("Code Excited Linear Prediction") coders, the stochastic excitation consists of a vector looked up in a predetermined dictionary. In the coders known as MPLPC ("Multi-Pulse Linear Prediction Coding") coders, the stochastic excitation includes a certain number of pulses the positions of which are sought by the coder. In general, CELP coders are preferred for low data transmission rates, but they are more complex to implement than MPLPC coders.
In order to determine the long-term prediction delay, a closed-loop analysis, an open-loop analysis or a combination of the two is used. The open-loop analysis is not demanding in terms of amount of calculation, but its accuracy is limited. Conversely, the closed-loop analysis requires much calculation, but it is more reliable as it contributes directly to minimising the perceptually weighted difference between the speech signal and the synthetic signal. In certain cases, an open-loop analysis is carried out first of all in order to limit the interval within which the closed-loop analyser will search for the prediction delay. This search interval must nevertheless remain relatively wide, since account has to be taken of the fact that that the delay may vary rapidly.
The invention aims particularly to find a good compromise between the quality of the modelling of the long-term part of the excitation and the complexity of the search for the corresponding delay in a speech coder.

Analysis-by-synthesis speech coding method with open-loop and closed-loop search of a long-term prediction delay


An optical recording and reproducing apparatus includes a deck, a spindle motor supported by the deck, a turntable combined with the shaft of the spindle motor, and a corrector for moving the spindle motor horizontally with respect to the surface of the deck in order to adjust the position of the turntable. Accordingly, the tracking error is easily corrected, thereby improving the performance of the apparatus.

The present invention relates to an optical recording and reproducing apparatus and, more particularly, to an optical recording and reproducing apparatus which can prevent a tracking error by correcting the position of a spindle motor which rotates a turntable.
The optical recording and reproducing apparatus is for reproducing the information recorded in optical recording media (which are referred to as a disk hereinafter) such as a compact disk, digital video disk, and a laser disk. A disk is loaded on the turntable installed in the optical recording and reproducing apparatus and rotates. An optical pickup detects an optical signal from a pit formed in the disk.
FIG. 1 is a perspective view schematically showing a portion of a conventional optical recording and reproducing apparatus. As shown in FIG. 1, an optical recording and reproducing apparatus 10 comprises a deck 11, a turntable 12 on which a disk (not shown) is loaded, a spindle motor 13 for rotating the turntable 12, an optical pickup 14 movable in a rectilinear and reciprocating manner on the deck 11, a motor 15 for driving an optical pickup 14, and a screw shaft 16 for converting the rotational movement of the motor 15 into rectilinear movement. The optical pickup 14, having a tooth gear portion (not shown) formed in one side thereof and engaged with the screw shaft 16, moves along guide shafts 17 fixed to the deck 11, according to the rotation of the screw shaft 16.
In the optical recording and reproducing apparatus having the above construction, focusing and tracking are performed in order to make the laser beam, incident on the disk, correctly land on a pit (not shown) formed in a track of the disk. While focusing is performed in a perpendicular direction to the disk, tracking is performed in the radial direction of the disk by a so-called three beam method. Using the three beam method, a tracking error is detected by comparing the light quantity of the main beam incident on the pit with that of the beams respectively incident on both sides of the pit.
Generally, since a tracking error is generated in the case where the machining precision of the parts is low or the assembly of the parts is poor, there were no alternatives but to improve the precision of machining of the parts and to assemble the parts correctly in order to decrease or prevent the tracking error. Therefore, an apparatus for effectively removing the tracking error is not provided when the tracking error occurs. Furthermore, when allowances of the parts are accumulated during assembly, means for compensating for the same is required after completing the assembly of the parts.

Optical recording and reproducing apparatus having device for correcting position of spindle motor


A method and an apparatus is disclosed for forming a one-piece introducer needle having a member portion and a needle portion by introducing a photoresist on a substrate. The temperature of the substrate is increased and then decreased. A photomask is deposited onto a substrate.

1. Field of the Invention
This invention relates generally to intravascular assemblies, and more specifically to a one-piece introducer needle and method of making the needle.
2. Background
Intravascular devices such as catheter assemblies are generally used for passing fluids between a device such as a syringe or a drip to or from body lumens such as veins or arteries, or other internal target sites. Such an assembly usually includes a hub, and a catheter tube. The tube is typically secured to the hub by means of an eyelet ring that is press fit within the nose of the hub. This hub and tube assembly is then mounted over an introducer needle comprising a sharp needle attached to a plastic hub. The sharp tip of the needle, protruding from the catheter tip, is used for piercing a body lumen so that access may be gained into the body lumen by the needle and subsequently the catheter. Once the catheter and the needle are located within the body lumen, the introducer needle is removed and discarded while the catheter tube remains in the body lumen. A syringe or a tube of a drip is then attached to the hub so that fluids may be passed through the hub and the catheter from the drip or the syringe to the body lumen. The hub is typically made of materials that provide sufficient rigidity thereto and the catheter tube is usually made of a material which is flexible.
Intravenous introducer needles with a surface groove are known in the art. One purpose of intravenous introducer needles is to allow a healthcare worker to be able to quickly observe when back-flow of blood enters a surface groove indicating that the needle has penetrated the vein.
Introducer hollow needles are conventionally made, one at a time, by a multistep process involving considerable time, labor, and precision machinary. For example, stainless steel hollow wire is straightened, cut to the desired length, tapered, and treated with a variety of finishing steps. There are additional disadvantages to introducer needles such as those described in U.S. Pat. No. 5,279,572, issued to Hokam (xe2x80x9cHokamxe2x80x9d), and European Patent No. EPO 893 137 A2, issued to Terumo Kabushiki Kaisha. For instance, Hokam comprises an intravenous introducer needle having two blood back-flow passage routes in which the needle comprises a material that is made of steel. The needle and the handle are manufactured separately through a machining operation and thereafter are fastened together. By requiring that a stainless steel needle be joined to a needle base, an assembling cost is incurred. It is therefore desirable to have a method of fabricating a one-piece needle that is able to reduce the operational cost such as machining of the needle and handle, and the cost of assembling these elements.
A method is disclosed for forming a one-piece introducer needle having a head. The method comprises introducing a photoresist material onto a substrate. The temperature of the substrate is increased and then cooled. A photomask is then deposited onto the substrate. The substrate is then exposed to light. A one-piece needle is formed from this process. Additional features, embodiments, and benefits will be evident in view of the figures and detailed description presented herein.

Photolithographic process for the formation of a one-piece needle


A method for straightening the edges of a work piece. The method includes the steps of determining the average edge position of each edge of the work piece, calculating an average edge line for each edge of the work piece, determining an actual corner point for each corner of the work piece, calculating a determined edge line through each of the actual corner points of the work piece, determining a number of actual edge points, determining if actual edge points are within the determined edge lines, and adjusting the determined edge lines inward until the actual edge points are within the determined edge lines.

Although numerous attempts have been made to automate the finishing process for textiles, carpeting, and similar materials, these attempts have not always been successful with respect to quality control and/or with respect to production time because of the general lack of uniformity in the work piece. For example, rugs may be cut by various means and have all types of variances therein. The width, length, and angles of the corners all may vary from piece to piece. The edges themselves may be cut with a bow or a crooked wave therein. Known automated systems that only accommodate the general length and the width of the work piece may not be able to accommodate these variations. The result thus may be an inefficient cutting at best or a damaged or rejected work piece.
There is a desire therefore for systems and methods for accommodating non-uniform work pieces in an automated finishing system. The systems and methods should be able to adapt to even minor variations in the work piece in a high speed and efficient manner.

Systems and methods for edge measurement


In an embodiment, a memory module includes a first group of multi chip packages, including one or more non-volatile memories, and a second group of multi chip packages, including one or more volatile memories, wherein the first and second groups of multi chip packages are electrically connected to a substrate. Various types of memory packages can be integrated into a single module that is mounted to the substrate, such as a printed circuit board, for improved size efficiency.

1. Field of the Invention
The present invention relates to a semiconductor memory module, and more particularly, to a memory module with different kinds of multi chip packages capable of being used as a substitute for a hard disk and a memory in a small-size computer.
2. Description of the Related Art
FIGS. 1A and 1B are diagrams illustrating a general memory module. FIG. 1A is a top plan view of the general memory module, and FIG. 1B is a front view.
Referring to FIGS. 1A and 1B, in the general memory module, a single kind of memory chip 11 is mounted on a printed circuit board (PCB) 12. In the memory module, the memory chips 11 may be mounted on one or both surfaces of the PCB 12. Further, a memory 13 built inside each of the memory chips 11 may be a volatile memory such as a DRAM or an SRAM, or a non-volatile memory such as a NAND flash memory or a NOR flash memory.
Conventionally, only DRAM chips, SRAM chips, or flash memory-type chips are mounted to one memory module, because only a single kind of memory chip can be mounted to the memory module.
Regarding possible state-of-the-art, future, small-size computers, a hard disk drive (HDD) and a memory may necessarily not be separately installed, and a non-volatile memory may be used instead of a hard disk, for example. Further, in a portable computer, a non-volatile memory, which is robust against outside impact, is used instead of a hard disk for storing data because the hard disk is weak on impact.
Furthermore, there has been a trend to generally minimize portable computer sizes. Therefore, to minimize the volume of a small-size computer that is portable or used in a vehicle, it may be necessary to reduce the volume of the computer by integrating a standard memory and a hard-disk memory into a single memory module, for example.

Memory module with different types of multi chip packages


An apparatus for setting bearings that support a shaft in a housing in effect projects critical surfaces from within the housing out of the housing where the axial distance between them may be measured. Where the bearings are tapered roller bearings, a measuring element seats against tapered raceways and indeed has two tapers so that it may be utilized with bearings having differing tapers on their raceways.

This invention relates in general to setting antifriction bearings and more particularly to a gauging apparatus and process for setting such bearings.
A shaft which rotates within a housing requires bearings of some type to support it in the housing, and where the shaft must rotate with precision or carry significant radial and axial loads, the bearings are often single row tapered roller bearings. When mounted in pairs, these bearings must be adjusted against each other to control the end play or preload in the bearings, or in other words, to bring the bearing to the proper setting. Too much end play detracts from the stability of the shaft. Preload, while keeping the shaft rotating about a fixed axis, if excessive, will produce too much friction within the bearings and cause them to experience early failure.
Within a pair of single row tapered roller bearings the setting depends on the axial spacing between the inner races or cones of the two bearings and the axial spacing between the outer races or cups of the two bearings. Various procedures and appliances exist for determining the proper spacing. Changing the spacing between either the cones or the cups will alter the setting for the combination.
Tapered roller bearings find widespread use in automotive equipment--from small automobiles to large trucks. In the typical rear wheel drive vehicle, the longitudinal drive or propeller shaft is connected to a pinion shaft which forms part of the vehicle's differential. That shaft rotates on two single row tapered roller bearings which are located in a housing. The shaft must rotate with considerable precision, lest the pinion carried by it will not mesh properly with the large ring gear in the differential and thereby produce noise and excessive wear. To achieve this precision, the shaft and housing must not only be machined accurately, but the bearings must be set properly to a condition of slight preload where no radial or end play exists in the pinion shaft.
Several procedures exist for setting these bearings. One of the more popular for setting the pinion shaft bearings of automotive axles controls the setting of the bearings with a spacer located between the inner races or cones. Typically, the cones are clamped between the pinion and a drive flange, which is in turn secured by a nut, with the spacer determining the distance between the two cones and hence the setting of the bearings.
But selecting the length of the spacer for a long time remained a formidable and time-consuming task, since it in essence relied on a trial and error procedure. With each new spacer, the pinion shaft would be rotated to determine the amount of torque transmitted by the bearings, and when the torque fell within an acceptable range, one assumed that the assembly contained a spacer of proper length.
A procedure developed by The Timken Company eliminates the trial and error procedure by measuring the spacing between the cones, notwithstanding their inaccessibility within the housing. In effect, the space separating the opposing faces of the cones is projected out of the housing where it can be measured. This procedure, however, utilizes a gauge which is dedicated to only bearings of a single type or series in that the gauge has surfaces which match the taper of the raceways for the bearings of only that series. Thus, where an axle assembly line carries axles having bearings of more than one series, only the axles having bearings to which the gauge is dedicated can have their bearings adjusted with the improved procedure. More traditional and time consuming procedures must be used for the remaining axles or else additional gauges must exist along the line for those remaining axles.
The present invention resides in a gauging apparatus which in effect projects surfaces of antifriction bearings out of a housing in which such bearings are located so that distances between critical surfaces may be measured remote from the housing. The apparatus has the capacity to accommodate two different types or series of bearings without undergoing modifications. This invention also resides in a process embodied in the apparatus.

Gauging apparatus and process for setting antifriction bearings


A still camera is provided with an area image sensor for obtaining digital image data, an LCD viewfinder, components for photographing image frames on a photo filmstrip in response to a shutter release operation, and a memory for storing the image data. The image data of one frame is written in the memory synchronously with each shutter release operation. In association with the image data of one frame, an ID code of the filmstrip and a frame number of the photographed image frame corresponding to the image data are written in the memory. Based on the data written in the memory, the display device can display a still image of the image frame photographed on the filmstrip, accompanied with the frame number of the photographed image frame. The still camera may be connected to a personal computer to transfer the data written in the memory to a memory of the personal computer, for displaying a still image of the photographed image frame along with the ID code and the frame number on an external monitor, or for making a hard copy of the photographed image frame.

1. Field of the Invention
The present invention relates to a portable still camera, and more particularly to a still camera which can photograph high-definition image frames on a silver-salt filmstrip and simultaneously pick up digital image data of each frame through an image sensor.
2. Background Arts
A wide variety of digital still cameras or electronic still cameras have been developed and brought in the market, as IC memories have a higher capacity and getting more compact. The digital still camera picks up a photoelectric image signal from a still image through a solid state imaging device, such as a CCD image sensor, and converts the image signal into digital image data to write it in a memory. The image data written in the memory can be processed in many ways instantly. For example, it is possible to transfer the image data to a peripheral apparatus for image processing like a personal computer, or to a video printer for making a hard copy.
On the other hand, still cameras that photograph still images on silver-salt photo film are well known. In these film-photo cameras, images are photochemically fixed on the photo film that has a higher resolving power even in comparison with the state-of-the-art imaging device with large scale highly integrated pixels. In view of the density gradation and the dynamic range, the silver-salt photo film is superior to the imaging device, so that a high quality still image is obtained by use of the photo film without the need for an expensive camera.
In order to obtain as high of quality image for the digital still camera as available by the film-photo camera, the digital still camera must have a large scale highly integrated imaging device, and a large capacity memory for storing enormous amount of image data that is obtained through the imaging device, i.e. at least 1 megabyte per frame, and 40 megabytes for a 40-exposure filmstrip. As a result, the scale and the cost of the digital still camera are both raised. It may be possible to compress the image data before storing, in order to save the memory capacity. However, once the image data is compressed, it is hard to reproduce the high quality image data from the compressed data even through an advanced image processing.
On the contrary, the film-photo camera can photograph high quality still images at a low cost, but the image on the photo film cannot be directly processed. For the image processing, it is necessary to convert the photographic image into electric image data through an electric viewer or a scanner.
Since a wide spread photo filmstrip can take 12 to 40 frames, an enormous memory capacity is necessary to store image data as an image file in order to maintain the high quality of the image, even while the image data is obtained from a single filmstrip through the scanner or the like. A hard disc or an optical disc, which is incorporated into a personal computer, does not have such an enormous capacity. Although it is possible to store image data of a limited number of designated frames in the memory of the personal computer, all frames on a filmstrip should be scanned to convert them into image data so as to permit designating desired frames. This is inefficient and time consuming. JPB 4-8993 discloses a digital still camera which writes data relating to each image frame, such as the date and the location of photography, along with image data of that frame into a recording medium. But this prior art does not disclose storing image data in association with photographic frames and photo filmstrips.
Meanwhile, a new type of film cartridge, called IX240 type, has been developed and marketed. The IX240 type film cartridge contains a roll of filmstrip whose entire back surface is coated with a transparent magnetic recording layer, so data relating to each frame may be recorded as a binary code on the magnetic recording layer after the exposure. The photo data written on the magnetic recording layer may include a shutter speed and a stop aperture size that are used for taking that frame, the date of photography, and so forth.
It is also known in the art to magnetically or optically record print option data on the filmstrip in association with each frame. The print option data include print format data that assigns a different print format, e.g. a panoramic size print, to one of the image frames that are recorded in the same size on the filmstrip. The print option data may also include the number of prints to be made from an image frame. Conventionally, the print option data is set up prior to exposure, and is recorded after each exposure. Practically, however, it is more useful to determine the print format and the number of prints while observing the photographed image frames after being developed. In addition, the photographer might miss the opportunity of a particular image while setting up the print option data prior to exposure pressing the shutter. Therefore, it is desirable that the camera allows setting up or revising print option data after the film has been exposed while observing the photographed image.


A bootstrap diode emulator circuit for use in a half-bridge switching circuit employing transistors connected to one another in a totem pole configuration, a driver circuit for driving the transistors, and a bootstrap capacitor for providing power to the high-side driver circuit. The bootstrap diode emulator circuit includes an LDMOS transistor having a gate, a back-gate, a source and a drain, the drain of the LDMOS transistor being coupled to the high-side supply node, the source of the LDMOS transistor being coupled to the low-side supply node; a gate control circuit electrically coupled to the gate of the LDMOS transistor, and a dynamic back-gate biasing circuit electrically coupled to the back-gate of the LDMOS transistor. The dynamic back-gate biasing circuit is operable to dynamically bias the back-gate of the LDMOS transistor when the LDMOS is turned on by applying a voltage to the back-gate of the LDMOS transistor that is close to but slightly lower than a voltage of the drain of the LDMOS transistor.

High voltage half-bridge switching circuits are used in various applications such as motor drives, electronic ballasts for fluorescent lamps and power supplies. The half-bridge circuits employ a pair of totem pole connected switching elements (e.g., transistors, IGBTs, and/or FET devices) that are placed across a DC high voltage power supply. For example, referring to FIG. 1, there is seen a conventional half-bridge switching circuit 100 as known in the prior art. Half-bridge circuit switching 100 includes transistors 105a, 105b connected to one another at load node "A" in a totem pole configuration, DC voltage source 110 electrically connected to the drain of transistor 105a and the source of transistor 105b, gate drive buffers DRV1, DRV2 electrically connected to the gates of transistors 105a, 105b, respectively, to supply appropriate control signals to turn on and off transistors 105a, 105b, and DC voltage supplies DC1, DC2 for providing electrical power to FET devices 105a, 105b, respectively. DC voltage supplies DC1, DC2 are generally lower in voltage that DC voltage source 110, since the gate drive voltage levels needed to properly drive transistors 105a, 105b are generally much lower than that supplied by DC voltage source 110. As shown in FIG. 1, the lower transistor 105b, DC voltage supply DC2, DC voltage source 110, and DRV2 all share a common node "B," and upper transistor 105a, DC voltage supply DC1, and DRV1 share common load node "A."
In operation, transistors 105a, 105b are diametrically controlled, so that transistors 105a, 105b are never turned on at the same time. That is, transistor 105b remains off when transistor 105a is turned on, and vice versa. In this manner, the voltage of load node "A" (i.e., the output node connected to the load) is not fixed, but rather assumes either the voltage level of DC voltage source 110 or zero volts, depending on which of transistors 105a, 105b is turned on at a given instant.
DC voltage supply DC2 may be derived relatively easily, for example, by tapping an appropriate voltage level (e.g., by using a voltage divider) from DC voltage source 110, since voltage supply DC2 and DC voltage source 110 share a common node. However, a "bootstrap" technique is required to derive DC voltage supply DC1, since voltage supply DC1 needs to be floating with respect to DC voltage source 110. For this purpose, voltage supply DC1 is derived from DC voltage supply DC2, for example, by connecting a high voltage diode DBS between DC voltage supplies DC1, DC2, as shown in FIG. 2. A capacitor CBS serves as voltage supply DC1 used to power driver DRV1.
When transistor 105b is turned on, load node "A" is effectively connected to zero volts, and diode DBS allows current to flow from power supply DC2 to capacitor CBS, thereby charging capacitor CBS to approximately the voltage level of DC power supply DC2. When transistor FET 105b is turned off and transistor 105a is turned on, the voltage at load node "A" will assume approximately the voltage level of DC voltage source 110, which causes diode DBS to become reverse biased, with no current flowing from DC2 to capacitor CBS. While diode DBS remains reverse biased, the charge stored in capacitor CBS supplies buffer DRV1 with voltage. However, capacitor CBS will supply voltage to DRV1 for only a finite amount time, and thus transistor M1 needs to be turned off and transistor 105b turned on to replenish the charge stored in capacitor CBS.
In many of today's half-bridge driver circuits, the bootstrap capacitor and the bootstrap diode DBS via are formed from discrete components provided off-chip, since the required capacitance of the bootstrap capacitor and the breakdown voltage and peak current capacity required of the bootstrap diode are too large to be produced on chip.
U.S. Pat. No. 5,502,632 to Warmerdam (hereinafter "the '632 reference") relates to a high voltage integrated circuit driver employing a bootstrap diode emulator. The emulator includes an LDMOS transistor that is controlled to charge the bootstrap capacitor only when he low-side driver circuit is driven. The LDMOS transistor is operated in a source follower configuration with its source electrode connected the low-side power supply node and its drain electrode connected to the bootstrap capacitor. While the LDMOS transistor is driven, the current conducted through a parasitic transistor is limited, since such conduction shunts current available for charging bootstrap capacitor C1. Furthermore, the back-gate of the '632 LDMOS transistor is clamped to a biasing voltage during normal operation to ensure a that a constant 4V gate-to-source voltage is required to turn on the LDMOS transistor.
Although conventional bootstrap diode emulators, such as the emulator described in the '632 patent, limit the current through the parasitic transistor, it is believed that such emulators disadvantageously permit at least some current to be shunted to ground by the parasitic transistor, thereby robbing the bootstrap capacitor of at least some of the current required for charging. In this manner, the bootstrap capacitor charges more slowly, making such conventional bootstrap diode emulators ineffective for certain applications, such as high frequency half-bridge driver applications.

Bootstrap diode emulator with dynamic back-gate biasing


The envelope-dependency of the distortion-introducing behavior of an RF power amplifier is used to derive a predistortion signal, that is derived from a plurality of respectively different work function representative signals. Each work function signal, in turn, is based upon the envelope of the input signal to the RF power amplifier. Prior to being combined into a predistortion control signal, each work function signal is controllably weighted in accordance with an error measurement comparison of the amplifier input signal with the amplifier output signal. The error measurement function yields a measure of the error contained in the-amplifier output signal, and drives a weight adjustment control mechanism, which controllably varies a set of weights for each of in-phase and quadrature components of the respectively different signal functions, in such a manner as to minimize the measured error.

The need for increased capacity accompanying the expansion of the wireless communications market is forcing a move away from analog modulation techniques, such as frequency modulation (FM), to digital modulation formats, such as time division multiple access (TDMA) and code division multiple access (CDMA). Since both TDMA and CDMA modulation require greater linearity than can be routinely obtained in an uncorrected, high efficiency (class AB) RF power amplifier, it is necessary to incorporate some form of amplifier distortion correction mechanism into the signal flow path through the amplifier. In addition, market forces are demanding amplifiers to simultaneously handle a multitude of narrow-band signals, thus also increasing the need for linearity.
The distortion introduced by the amplifier causes the phase and amplitude of the output signal to depart from the respective phase and amplitude of the input signal, and may be considered as an incidental (and undesired) amplifier-sourced modulation of the input signal. Observation and analysis of this distortion-introducing behavior of an RF power amplifier by the inventors has led to the conclusion that the distortion is primarily driven by the envelope (instantaneous amplitude) of the input signal. For example, as the amplitude of the input signal varies, the shape of the amplifier output signal does not exactly track that of the input signal. Also, the harder the amplifier is driven (by the peak of the signal), the larger the phase delay through the amplifier.

Adaptive compensation of RF amplifier distortion by injecting predistortion signal derived from respectively different functions of input signal amplitude