An apparatus for mirror-polishing a thin plate, wherein uniformity of tightness in a stretched condition across an elastic film can be achieved and a polishing pressure distribution on the thin plate is uniformalized, so that constant polishing stock removal is realized and high flatness polishing is made possible. In the apparatus, the thin plate is held on a thin plate support mounted on a rotatable press member and the thin plate is pressed to a polishing means by the press member, and the apparatus has features that a holding surface for the thin plate is formed by a flexible elastic film; the elastic film is fastened to the press member or a part mounted thereto in a condition that the elastic film is sandwiched between a spacer and a holding piece; and a pressure, which presses the thin plate held on the elastic film to the polishing means, is adjusted by applying a back pressure to the thin plate with a fluid feed means, while adjusting tightness of the elastic film by the space.

1. Field of the Invention
The present invention relates to an apparatus for mirror-polishing a thin plate. More particularly, the invention relates to an apparatus for mirror-polishing a thin plate used for mirror-polishing a semiconductor wafer (hereinafter referred to as wafer) to a high flatness.
2. Related Art
In a fabrication process of a semiconductor integrated circuit, for example, a design rule applied to a device has been narrowed and a depth of focus in a stepper in a photolithography step has become shallower in the trend of ever increasing integration of the device. Accordingly, requirement for a higher flatness of a wafer has also become more demanding in a mirror-polishing process for the wafer.
Conventionally, a mechano-chemical polishing method, which is a combination of mechanical polishing and chemical polishing, has been used in an apparatus for mirror-polishing a wafer.
In this mechano-chemical polishing method, a wax method, for example, has been used, comprising: fixing with wax a wafer on a lower surface of a support mounted on a freely rotatable, press member; and subjecting the wafer to abrasion with an unwoven polishing pad, as a plashing means, fixed on a major surface of a turn table, while being pressed. In the wax method, however, there are technical limitations to improvement on a flatness of the wafer, since it is difficult to apply the wax on the lower surface of a support uniformly and foreign matter invades into a gap between the wafer and the lower surface of a support, so that generation of dimples can not be avoided.
A waxless method has been also used, in which a wafer is held on a lower surface of the support with a backing pad in a state of sponge lying therebetween and the wafer is polished in a similar way to that of the polishing process in the above mentioned wax method. In this waxless method, however, there is also a problem that pores on the surface of the backing pad in the state of sponge are loaded with solids in polishing slurry or the like and an elasticity of the pad is locally changed, so that a flatness of the wafer is degraded. Accordingly, in the waxless method, there is a requirement that frequent exchanges of backing pads are indispensable in order to prevent degradation in flatness of the wafer.
In consideration of such circumstances, an apparatus for mirror-polishing, which adopts an elastic film holding method, as disclosed in Laid-open Japanese Patent Application No. 5-69310, has been recently proposed. This apparatus employs, as shown in FIG. 4, an elastic film 91 with flexibility on a supporting surface thereof for the wafer. As an material of the elastic film 91, a sheet made of synthetic rubber such as silicone rubber or the like, or a reinforced rubber or reinforced vinyl resin with any of fibers and cloth or the like is used. In such an apparatus for mirror-polishing, the elastic film 91 is fastened on a cylinder-like holder body 92 with application of uniform tension, a surface (back surface) of the film opposed to the surface thereof, on which the wafer is held, is exposed to a pressure adjusting fluid for pressing the wafer, said fluid is supplied from a fluid feed/exhaust apparatus, not shown. A ring 94 is mounted on the outer periphery of the holder 92, as shown in FIG. 5, in such a manner that the ring 94 is free to movable vertically, the thin elastic film 91 is adhered or mechanically fixed in a squeezing manner on the film 94 and the ring 94 is adjustably moved upward or downward with a screw 95, so that the thin elastic film may be tightened in a uniform manner. A mark 96 indicates a polishing pad fixedly held on a major surface of a turn table.
The above apparatus for mirror-polishing still has a problem. In order to attain a uniform polishing stock removal on a wafer, conditions of tightness of the elastic film 91 are important. In the apparatus employing the elastic film holding method, the screw 95 works for vertical shifts of the ring 94 in order to adjust the tightness of the elastic film 91 but it is difficult to properly determine a position itself of the ring on the outer surface of the holder 92 by adjusting a degree of clamping-down of each screw 95 and besides it is more difficult to uniformalize clamping-down degrees of screws 95, said screws 95 being located on the outer periphery of the holder 92. For the above reason, in the apparatus, uniform tightness across the elastic film 91 working as a holding surface for a wafer W has not been achieved. In the apparatus, moreover, since the outer periphery of the holder 92 and the inner periphery of the ring 94 are respectively uniform in diameter, a gap is easy to be created between the outer periphery of the holder 92 and the inner periphery of the ring 94, which leads to another problem that such a structure has poor gastightness or fluidtightness.
Such problems are not restricted to the case of a semiconductor wafer but generally occur in mirror-polishing of a thin plate.

Apparatus for mirror-polishing thin plate


A processing system cooperates with an atomic force microscope operating in ramp mode at a ramp frequency is configured to collect data indicative of at least one of physical and chemical properties of a sample. The system collects data indicative of probe movement at a frequency that is higher than the ramp frequency. This data comprises a second-order portion of the probe's signal. Based at least in part on the second-order portion, the processor obtains a parameter that is indicative at least one of a physical and a chemical property of a sample.

Scanning probe microscopy, also known as atomic force microscopy, is a way to study force interactions between a probe and sample surface. It is broadly used to visualize features on a sample surface that have dimensions from hundreds of microns down to sub-nanometer scale.
In atomic force microscopy, a probe attached to a cantilevered member responds to forces that result from proximity or contact with some sample surface. This force affects the tip's motion. The tip's motion therefore provides a measure of the force.
By scanning the probe's tip across the surface of a sample, one can obtain values of the extent of deflection as a function of spatial position. This allows one to build a two-dimensional map showing values of some surface parameter.
A difficulty that arises is that building such a map takes time because an entire region needs to be scanned. An obvious solution to the problem of slow scanning is to scan faster. But a cantilever arm has its own resonance characteristics. When one scans faster, the output signal of the microscope becomes a superposition of three components. The first component consists of the deflections caused by slow mechanical interaction with the surface. The second component consists of various second-order effects, such as deflections that arise from all other sources, including those that arise from the dynamic properties of the cantilever arm itself, and/or from the sliding interaction between the AFM probe and sample surface. The third component consists of instrumental and environmental noise.
From the combination of these three components, one can filter out an output signal. However, this filtering process is not perfect. As a result, the output signal can show artifacts that impair the accuracy of the measurement. To minimize formation of such artifacts, it is known to slow down the scanning. But this results in undesirable excessively slow scanning.

Exploitation of second-order effects in atomic force microscopy


A debugging information display device is provided which concurrently displays a source list and debugging information when the source list is displayed through a debugger. A vectorizing line extractor, a vectorizing degree analyzer and a breakpoint-logical vector length information fetching unit are provided on a compiler side, and debugging information is affixed to an execution program output from the compiler. A vectorizing degree fetching unit is provided on the debugger side, and displays, together with source lines, vectorizing lines to be vectorized and the corresponding vectorizing degree information fetched from the debugging information. Also, a logical vector length analyzer and a real vector length fetching unit are provided to display logical and real vector lengths simultaneously. Further, a breakpoint setting unit and a breakpoint information analyzer are provided so that set breakpoints and specifiable breakpoints can be displayed when the source is displayed.

1. Field of the Invention
The present invention relates to a debugging information display device displaying debugging information, and more particularly, to a debugging information display device displaying debugging information during debugging, so that a program can be debugged smoothly.
2. Description of the Related Art
Generally, in an environment in which a vector compiler is used to speed up execution of a program by a computer, the program can be debugged smoothly and the performance of the program improved if a vectorization status with respect to a source program and vector length status at the time of translation and execution are made known to the user when a debugger is used.
Also when a debugger is used, breakpoints are set interrupting execution of a program. If breakpoints that can be specified (i.e., specifiable breakpoints) and set with respect to a source program are known, the frequency of setting a breakpoint to an erroneous position is decreased and debugging can be performed smoothly.
FIG. 1 illustrates an example of a conventional debugging environment. Typically in a conventional environment in which a source program 1 is compiled by a compiler 2 running on a computer, the compiler 2 first analyzes vectorization information, outputs a source list 3 with the vectorization information in the form of a file remaining on the computer and/or printed on paper, and then outputs an execution (or object) program 4. The execution program 4 is output in the form of an executable program section 4a and specifiable breakpoint information 4b analyzed by the compiler 2. Subsequently, the execution program 4 is input to a debugger 5, which aids in debugging of the program. At the time of debugging, the source list 3 with the vectorization information previously output is required.
The source program 1 and the source list 3 are stored in a memory as part of a computer, and the compiler 2, the execution program 4, and the debugger 5 are executed by the computer (not shown in FIG. 1).
Thus, the vectorization information is output together with the source list 3 at the time of compiling. The source list 3 is indispensable to debugging of the execution program 4 using the debugger 5. Therefore, the source list 3 must be output each time the compilation of the source program 1 is performed by the computer. Further, since the execution program 4 to be debugged and its source list 3 previously output at the time of compiling are separate from each other, they may be mismatched when debugging is attempted.
In the conventional debugging environment, the vectorization information necessary for debugging is acquired from the source list. Thus it is necessary that the source list output be specified in advance at the time of compiling. Further, it is difficult to learn from the debugger alone the lines to be vectorized and their degree of vectorization with respect to the source program.
Although in a conventional compiler, logical vector lengths are defined at the time of translation, the logical vector lengths may turn into different real vector lengths for memory-related reasons when the execution program is actually executed. It is, however, extremely difficult to ascertain in the debugger the information about both the logical and real vector lengths at the same time.
Further, with the conventional debugger, the information about set breakpoints can be obtained. However, information on where breakpoints can be set is not displayed. Further, the source list output also does not include such information. Therefore, whether the execution program can be interrupted or not cannot be determined unless a breakpoint is actually set. In some debuggers, the breakpoint is set to a next line instead of the line at which the breakpoint is desired. In actuality, the program may not be interruptable exactly at a desired point. Thus, to locate a breakpoint which can be specified, a set command must be repeatedly executed, consuming labor for the setting of the breakpoint.


A system including a memory configured to store instructions, a host processor, an interface coupling the non-volatile memory and the host processor, and a device driver is provided. The device driver is configured to execute commands stored in the memory to retrieve a maximum queue size value from a hardware queue, wherein the hardware queue is associated with an interface between the host processor and a non-volatile memory, to determine multiple software queues associated with the hardware queue, to read an input/output count for a software queue selected from the software queues, to decrease the assigned queue depth, when the input/output count for the software queue is lower than an assigned queue depth, and to increase the assigned queue depth when the input/output count for the software queue is greater than the assigned queue depth.

Non-volatile memory express (NVMe) is a commonly used interface specification for accessing non-volatile storage media hosted by computers executing multiple applications. NVMe provides the ability to include multiple command queues in a device driver, thereby allowing greater parallelism and reduced input/output (IO) overhead. Device drivers including controller hardware and associated software feature multiple hardware and software queues to exploit these capabilities. However, in dynamically changing IO workload scenarios, current technologies are unable to adjust the queues for device drivers, thereby resulting in numerous IO failures to running applications due to queue overload. These IO failures eventually cause a deterioration of application performance, overall system downgrade, and eventual failure.
In the figures, elements and steps denoted by the same or similar reference numerals are associated with the same or similar elements and steps, unless indicated otherwise.

Dynamic queue depth management with non-volatile memory controllers

Hewlett Packard Enterprise Development LP


Sealant compositions for sulfur coated fertilizer particles are mixtures of wax materials and additives which provide improved moisture barrier properties and abrasion resistance. The sealants have penetration values measured by ASTM D-1321 of at least 20 at 25.degree. C., and congealing points measured by ASTM D-938 of between about 50.degree. C. and about 100.degree. C. The sealed fertilizer particles are conditioned with particulate materials with a surface area of at least about 2 m.sup.2 /g and an oil absorption of at least about 100%. A method for the production of abrasion resistant sulfur coated fertilizers is also disclosed.

1. Field of the invention
Fertilizer granules or prills which have been coated with sulfur to slow the rate of dissolution of the nutrients in the soil when they are applied as a fertilizer can be coated with a sealant to improve the slow release properties of the particles. This invention relates to sealant compositions with improved slow release properties and abrasion resistance. Small particle inorganic materials are added as conditioners to provide acceptable flow properties.
2. Description of the prior art
The process for sulfur coating of urea granules or prills was developed in 1968 by the Tennessee Valley Authority (TVA) in Muscle Shoals, Alabama, as an economical system for reducing the rate of dissolution of urea particles when they are applied to the soil as fertilizer. U.S. Pat. No. 3,342,577 describes this sulfur coating process and also the sealant material that was necessary to fill in the holes that result naturally in the sulfur coating as it cools. The TVA process is also described in Sulphur Inst. J. 4(3) 2-6 (1968), ibid. 8(4) 2-5 (1972a) and ibid. 8(4) 6-8 (1972b). The TVA recommendation for the sealant is a mixture of 30% polyethylene resin in 70% bright stock mineral oil. A conditioning agent is applied over the sealant to provide free flowing particles.
U.S. Pat. No. 4,042,366 describes a modification of this process in which particles of water soluble nutrients are embedded in a soft petroleum wax coating to provide anticaking properties to the coated particles as well as nutrient benefits.
The process is further described in Sulfur Coating of Urea Treated with Attapulgite Clay, Gullett, G. L.; Simmons, C. L.; and Lee, R. G.: presented at the 198th American Chemical Society meeting in Miami Beach, Fla., in September 1989.
The requirement for a sealant for sulfur coated urea (SCU) has been documented by McClellan and Scheib (Sulphur inst. J. 9(3/4) 8-12 (1973)), and by Scheib and McClellan ibid. 12(1) 2-5 (1976).
A description of slow release urea and NPK fertilizers is given in Hort. Rev. 1 79-140 (1979).
A number of products have been developed recently for the purpose of providing sealed SCU compositions that have improved slow release properties and also do not require the use of a conditioner. U.S. Pat. No. 5,300,135 describes the use of mixtures of polymers and hard waxes as sealants for SCU. SCU sealed with these compositions are free flowing particles which do not need a conditioner. The addition of the polymer provides improved abrasion resistance over SCU sealed with the wax alone. U.S. Pat. No. 5,423,897 describes surfactant modified hard waxes used as sealants for SCU. The surfactants provide anti-blocking properties in the waxes, and the coated SCU does not require a conditioner. U.S. Pat. No. 5,478,375 describes sealants for SCU which are mixtures of fatty esters of polyhydric alcohols and polymers, crosslinked with a transesterification catalyst. These compositions do not require a conditioner. U.S. Pat. No. 5,599,374 describes a urethane polymer coating for SCU which produces free flowing particles with improved impact resistance.
The use of hard non-blocking sealants, while it improves the slow release properties and eliminates the need to apply conditioners, does not provide adequate impact resistance. Product produced by these methods must be transported, blended and applied by methods that avoid high impact or vigorous abrasion, or a significant portion of the slow release properties may be lost. Urea and blended fertilizers, when they are mixed and bagged, must be labeled with their water insoluble nitrogen (WIN) content, which is a measure of the nitrogen which is not immediately soluble in water, and it is the responsibility of the manufacturer to assure that the value does not decrease below the labeled value during shipping and storage. Thus a significant loss in WIN resulting from handling in modem high-speed equipment can create a situation in which the fertilizer is mislabeled and subject to recall.

Sulfur coated fertilizers with improved abrasion resistance


Methods and apparatus to improve the speed and reliability of decoders are presented herein. Namely, a priori knowledge of Walsh space information is used to increase the speed at which messages are decoded. In systems where control messages contain transmission parameters of concurrently transmitted packet data, a faster demodulation and decoding of control messages allows a receiver to demodulate the packet data sooner, so that a shorter buffer is needed to store the received packet data. The receiver uses the Walsh space from the previous successfully decoded message to first decode the current message. If the decoding attempt is unsuccessful, the receiver then uses a neighboring Walsh space to decode the current message.

1. Field
The present invention relates generally to communications, and more specifically, to decoding signals received on wireless communication systems.
2. Background
The field of wireless communications has many applications including, e.g., cordless telephones, paging, wireless local loops, personal digital assistants (PDAs), Internet telephony, and satellite communication systems. A particularly important application is cellular telephone systems for mobile subscribers. As used herein, the term "cellular" system encompasses both cellular and personal communications services (PCS) frequencies. Various over-the-air interfaces have been developed for such cellular telephone systems including, e.g., frequency division multiple access (FDMA), time division multiple access (TDMA), and code division multiple access (CDMA). In connection therewith, various domestic and international standards have been established including, e.g., Advanced Mobile Phone Service (AMPS), Global System for Mobile (GSM), and Interim Standard 95 (IS-95). IS-95 and its derivatives, IS-95A, IS-95B, ANSI J-STD-008 (often referred to collectively herein as IS-95), and proposed high-data-rate systems are promulgated by the Telecommunication Industry Association (TIA) and other well known standards bodies.
Cellular telephone systems configured in accordance with the use of the IS-95 standard employ CDMA signal processing techniques to provide highly efficient and robust cellular telephone service. Exemplary cellular telephone systems configured substantially in accordance with the use of the IS-95 standard are described in U.S. Pat. Nos. 5,103,459 and 4,901,307, which are assigned to the assignee of the present invention and incorporated by reference herein. An exemplary system utilizing CDMA techniques is the cdma2000 ITU-R Radio Transmission Technology (RTT) Candidate Submission (referred to herein as cdma2000), issued by the TIA. The standard for cdma2000 is given in the draft versions of IS-2000 and has been approved by the TIA, and the 3rd Generation Partnership Project 2 "3GPP2". Another CDMA standard is the W-CDMA standard, as embodied in 3rd Generation Partnership Project "3GPP", Document Nos. 3G TS 25.211, 3G TS 25.212, 3G TS 25.213, and 3G TS 25.214.
The telecommunication standards cited above are examples of only some of the various communications systems that can be implemented. Within these various communications systems, multiple users must share limited system resources. In accordance with the actual system implementation, resources such as frequency bandwidth, time, transmission power, or spreading code assignments are typically shared by multiple users within the system. In a FDMA system, the system bandwidth is divided into many frequency channels and each frequency channel is allocated to a user. In a TDMA system, the system bandwidth is divided into many time slots and each time slot is allocated to a user. In a CDMA system, the system bandwidth is simultaneously shared among all users by using spreading codes, wherein each user is assigned a spreading code.
User demand drives the development of higher transmission data rate systems. In systems that can transmit data traffic in packetized formats, such as TDMA and CDMA systems, control information is transmitted containing essential information, such as the identity of the addressee, the modulation format, the coding format, the transmission timing, and the orthogonal codes used to cover the data. Receivers that cannot decode this control information correctly will fail to receive the packet data. Furthermore, receivers that cannot decode this information in a timely manner will have to store portions or all of the possible orthogonal codes with sufficient resolution in a memory element, whereupon the stored codes can be used to de-modulate data information at a later time. Such an implementation would increase the complexity and cost of the receiver.
It is therefore desirable to provide means for the control information to be decoded with a high probability of success and in a timely manner. Possible methods of increasing the probability of correctly decoding the control information are to increase the transmission power at which the control information is transmitted or to increase the duration of the transmission. However, these methods are undesirable due to the increased consumption of system resources, which in turn, decreases the amount of available resources for the transmission of data. Methods to increase transmission data rates are useless without the ability to quickly and accurately decode received information. Hence, there is a current need for improving the speed and accuracy at which decoders operate.


Interdigitation and surface mounting of a block filter that has at least a first resonator and that has at least a first pole and at least a first zero in its transfer function provides a surface mountable block filter having selectable frequency rejection response operation.

As mobile and portable radios and electrical devices have decreased in size, transceivers and filters utilized therein have been modified to be more space efficient. Surface mountable filters that mount directly to a substrate have been utilized to reduce electrical component space requirements. Typically, a transfer function of a block filter component is associated with operating characteristics of that block filter. In theory, the transfer function typically may have a numerator with roots that are termed zeros, and a denominator with roots that are termed poles. However, surface mountable block filters have previously failed to include filters having transfer functions with zeros, lacking selectable frequency rejection response characteristics. There is a need for a surface mountable block filter that, while utilizing a transfer function with at least one pole, simultaneously provides for selectable frequency rejection response operation.

Surface mountable interdigital block filter having zero(s) in transfer function


A circuit having a dynamically adjustable common mode rejection ratio. The circuit has a high common mode rejection ratio without the need for input transformers. The circuit's ability to adjust the circuit's common mode rejection ratio is enhanced by the circuit's high input impedance. The circuit includes first and second input terminals, and output terminals. A positive leg runs from the first input terminal to the first output terminal, the positive leg including a resistor, and a negative leg runs from an input terminal to an output terminal. The digital signal processor controls a potentiometer on one of the legs to dynamically adjust the common mode rejection ratio of the circuit.

Conventionally, operational amplifiers have well-matched bipolar junction transistor or field effect transformer front ends and sufficiently high input impedance when operating in the Mega-ohm and Giga-ohm levels such that they achieve common mode rejection ratios (CMRR) exceeding ninety decibels (dB), that is CMRR>90 dB. However, in practice, external components are often needed on the front end of many instruments—such as operational amplifiers—to filter and shunt input bias currents. Thus, there is room for improvement in the art.

Dynamically adjusting common mode rejection ratio


One or more techniques and/or systems are disclosed for a portable gas-fired heater comprising a housing, a burner assembly, and a carbon dioxide detector system. The housing may, at least, partially enclose one or more fuel sources. The burner assembly can be enclosed by, and recessed into, the housing.

Gas-fired portable heaters are used in multiple environments. The heater typically includes a housing having a combustion chamber. The housing has an inlet for receiving air into the chamber. A mixture of fuel and air is introduced into the chamber where combustion occurs, to provide a heat. Often, a plenum directs the heat toward a heating surface, to distribute it over the surface thereof.
These types of heaters are often used for outdoor use due to the emission of carbon monoxide and other potentially harmful combustion products. Prior designs of these types of heaters are typically not considered safe for operation in an enclosed environment, such as small recreational enclosures, including tents, truck-caps, fishing huts, trailers, vans, etc. These prior designs may not meet safety certification targets regarding combustion requirements (e.g., release of combustion products) at a high and low firing condition and at a reduced pressure, or other safety requirements.

Gas-fired heater with carbon dioxide detector


A breakaway buckle has a keeper attachable to a first strap and a secure attachable to a second laterally disposed strap. The secure has a tongue releasably retained in the keeper by overlapping interlocked locking surfaces on both components. Cam surfaces on the secure and keeper coact in response to lateral and/or torsional forces exerted on the secure to reduce the area of overlap between the locking surfaces and thereby facilitate separation of the secure from the keeper.

1. Field of the Invention
This invention relates to buckles of the type employed to interconnect manually releasable straps on backpacks and the like, and is concerned in particular with the incorporation of a breakaway release feature in such buckles.
2. Description of the Prior Art
Shoulder straps on backpacks tend to spread apart and slip off the shoulders of the wearer as he or she walks or moves about. As a solution to this problem, it is known to employ a length of web strap spanning over the sternum to connect the shoulder straps. The "sternum strap" is anchored to the face of each shoulder strap with friction fittings that can be adjusted vertically as desired. This configuration typically includes a side-release buckle that allows the wearer to connect or part the sternum strap as needed to don and doff the backpack.
The known side-release buckles suffer from a number of problems, including, inter alia, lack of durability, difficulty in accessing release mechanisms, resistance to releasing under heavy loads, etc. Most of these problems have been addressed by the lanyard-releasable buckle disclosed in U.S. Pat. No. 6,637,083.
There remains, however, a problem stemming from the buckle's inability to open unless its release mechanism is manually operated or it breaks under heavy loading. Thus, when employed as a sternum buckle, injury, particularly to the throat area and larynx, may result if the wearer attempts to doff the backpack without first releasing the buckle.
There exists a need, therefore, for a buckle that is not only readily releasable by manually activating its release mechanism, but that also is automatically releasable in a "breakaway" fashion if the sternum strap is subjected to lateral and/or torsional forces. This typically will be the case in emergency situations where the wearer is prevented or distracted from manually releasing the buckle.


The invention provides compositions comprising 4-APAA compounds and methods for treating disorders involving inflammation of the intestinal system, such as inflammatory bowel disease. The methods and compositions of the invention also include combinations of 4-APAA compounds and 5-ASA compounds for treatment of such disorders.

A wide variety of bowel diseases are related to the inflammatory processes. Two of the most important inflammatory conditions are ulcerative colitis (UC) and Crohn's disease (CD). UC is a chronic inflammatory condition of the internal lining of the colon. It extends from the rectum and can involve the entire colon. CD can involve the entire gastrointestinal (GI) tract but is usually limited to the small and large intestine. CD can extend through the bowel wall leading to other complications. About 20% of patients with CD have disease isolated to the colon. Both UC and CD are chronic conditions, and treatment typically follows a two-phase treatment approach: induction and then maintenance of remission. UC and CD are characterized by abdominal pain, bloody diarrhea, and bowel wall inflammation. For many patients, the disease is episodic, occurring as a cycle of flares and remissions with considerable morbidity. Symptoms can be mild or very severe and disabling. They can develop gradually or have a sudden onset.
Approximately one million Americans suffer with either UC or CD. In Western Europe and the United States the prevalence of UC is 70 to 150 per 100,000 while the prevalence of CD is 40 to 100 per 100,000. These diseases can affect persons of any age, but are more common in the second and third decades. Males and females are equally affected. Risk of disease is higher in some ethnic groups than others. Overall, the incidence of UC appears to be stabilizing, but the incidence of CD is increasing, especially among young people.
The causes of UC and CD are unknown, although genetic predisposition, infectious bacterial and viral agents, as well as environmental factors are suspected to play a role. Recent experimental and clinical studies suggest that the initiation and pathogenesis of CD and UC are multifactorial, involving interactions among genetic, environmental, and immune factors. Regardless of exactly how these interactions ultimately promote chronic gut inflammation, it is becoming increasingly apparent that the immune system plays a critical role in disease pathogenesis.
Current therapies for inflammatory bowel diseases fall into 4 classes: 1) corticosteroids 2) aminosalicylates, 3) immunomodulators and 4) antibiotics. Aminosalicylate drugs such as sulfasalazine or mesalamine are the mainstay of treatment for mild to moderate disease. Immunomodulatory agents such as azathioprine and 6-mercaptopurine are used as steroid-sparing agents but have a variety of adverse side effects, often precluding use in many patients. Additional immunomodulators such as monoclonal antibodies against tumor necrosis factor α (anti-TNFα) are effective in some patients with Crohn's disease.
Following introduction into clinical medicine for the treatment of rheumatoid arthritis 40 years ago, aminosalicylates (e.g., 5-ASA) have become the primary treatment for ulcerative colitis (UC). Aminosalicylates (e.g., 5-ASA) are first-line inductive agents for the treatment of mildly to moderately active disease, as well as the primary maintenance therapy for remitted UC, and are used in conjunction with corticosteroids during the transition from inductive to maintenance therapy.
Sulfasalazine was the original prototype aminosalicylate and was designed with the concept of combining an anti-bacterial agent (sulfapyridine) and an anti-inflammatory agent (5-ASA):

Although the mode of action of sulfasalazine is not clearly understood, multiple clinical studies indicate that the major therapeutic action resides in the 5-ASA moiety. The primary limitation of sulfasalazine is the significant rate of adverse events related to the sulfapyridine moiety, thereby compromising the clinical usefulness of sulfasalazine. As many as 30 to 40 percent of patients are unable to tolerate the doses required to provide optimal treatment benefits.
Commercially available products (mesalamine, ASACOL®, PENTASA®, ROWASA®) use various means of delivering 5-ASA to inflamed intestinal mucosa. All of these compounds deliver 5-ASA without the sulfapyridine component of sulfasalazine that causes most of the adverse reactions.
Olsalazine, having the following formula, has been used to treat ulcerative colitis.

In addition to being relatively expensive to make, olsalazine can have adverse side effects, including diarrhea.
It is known to use azathioprine (6-(1-methyl-4-nitroimidazol-5-ylthio)purine) in the treatment of inflammatory bowel disease. Azathioprine has the following chemical structure:

It is also known to use 6-mercaptopurine, a metabolite of azathioprine, to treat inflammatory bowel disease. 6-mercaptopurine has the following chemical structure:

Methotrexate (L-4-amino-N10-methylpteroyl-glutamic acid) has also been used to treat inflammatory bowel disease. Methotrexate has the following chemical structure:

Actarit (4-acetylaminophenylacetic acid) is an immunomodulatory drug that was approved in Japan in 1994 for use in the treatment of rheumatoid arthritis. Four-aininophenylacetic acid (4-APAA) is a precursor to actarit and in vivo studies demonstrate that 4-APAA undergoes acetylation to form actarit. Both actarit and 4-APAA possess immunomodulatory activity.
The polypeptide cyclosporine, which has traditionally been given to transplant patients to prevent organ rejection, has also been used to treat inflammatory bowel disease. The use of cyclosporine to treat IBD can be limited, however, by the various side effects associated with this medication. These side effects include high blood pressure, kidney damage, tremors, headaches, seizures, excessive hair growth, excessive gum growth, confusion, coma, and gout.

This patent is subject to a terminal disclaimer.

Methods and compositions employing 4-aminophenylacetic acid compounds


The invention relates to an air purification apparatus substantially comprising a suction part, a ventilator housing with one or several ventilators and one or more air filters disposed before or after the ventilator, wherein a housing implemented with a base comprises modular function parts disposed tower-like one above the other, one engaging the other in sealing fit and readily detachable one from the other and at least one pivoted lever disposed pivotably on the lateral portion of the housing by means of a pivot receptor in the direction of the arrow and extending over all parts of the housing from the outside and clamping them together. The air purification apparatus additionally fastenable on the ceiling is usable in particular as spot suction, as ventilation or overpressure or as clean-air purification apparatus.

1. Field of the Invention
The invention relates to an air purification apparatus. Such air purification apparatus have become known in a large variety of implementations. They substantially comprise a suction part, a ventilator housing, in which one or several ventilators are disposed, and one or several air filters disposed in front or after the ventilators in order to draw in the air from a specific suction opening, to force it through the ventilator housing and conduct it through the air filters in order to separate through the filters the dust or other floating particles.
2. Description of the Prior Art
The disadvantage of previously known air purification apparatus, which operate according to the dry-filter principle, is the inferior replaceability of the filters.
By that is understood the following:
In the previously known apparatus several different filter media are combined in a single filter element which entails the disadvantage that the filter element can only be exchanged as a whole which entails relatively high costs and, moreover, is often unnecessary because only one of the various filters types combined in the element, is contaminated and requires replacement while the others are not yet in need of replacement. This leads to the disadvantage that the individual filters of the air purification apparatus, as a rule, are not individually replaceable but rather can only be replaced as a whole filter element.
A further disadvantage of the known air purification apparatus is that the filters cannot be disposed in the housing of the air purification apparatus at different locations. For example, it may sometimes be desirable to place the rough-dust filter as closely as possible in the proximity of the suction opening of the apparatus in order to separate at this site the maximum quantity of rough dust and to protect other parts of the apparatus against this rough dust. In the known apparatus it is not possible to assign, for exam e to the rough-dust filter, more than one succeeding fine-dust filter because the sequence of filters and the number of filters in the known air purification apparatus is precisely predetermined and determined by the shape of the housing and the housing disposition.
A further disadvantage of the known air purification apparatus is thirdly that the filters as such cannot be exchanged rapidly, i.e. considerable disassembly work is required in order to remove such filters from the housing. It is herein known to close the housing with toggle lever closures or other clamping closures which can only be opened with great effort.
A further, fourth, disadvantage of the known air purification apparatus is that, as a rule, in the known apparatus the motor part is disposed last directly in front of the outflow part. This entails the disadvantage that during the operation the motor itself emits foreign particles, for example particles due to friction in the bearings, plastic particles front ventilator vines and others so that the motor itself, due to its own activity, introduces particles into the space to be purified which leads to the fact that a clean-room atmosphere is not attainable.


A cleaning device and method of manufacture comprising (1) a cleaning tape element comprising a plurality of individual filaments such as bristles or fibers, the plurality of individual filaments each having (i) a cleaning tip disposed at a first end of the filament, and (ii) a second end, and (iii) means for maintaining the plurality of individual filaments in at least one, single filament-wide row, thereby forming a tape and (2) a base portion, the plurality of individual filaments coupled to the base portion adjacent their respective base ends.

The toothbrush is one of the most common devices known to man. Modern twentieth-century oral hygiene for people in all parts of the world includes the daily use of a tooth brush of some sort, often used more than once per day and often used in conjunction and/or association with other devices, including dental floss, dental tapes, regular wooden or plastic toothpicks, water picks, gum stimulators and the like.
The typical pharmacy carries numerous types of toothbrushes, including different sizes, such as for children or for adults, different stiffness bristles, such as "soft", "medium" and "hard", as well as numerous different manufacturers which each typically have their own unique features, including various colors or patterns, various sized or shaped handles, etc.
Polyester or other polymeric fibers such as are typically used in modern toothbrushes have long been available. They can be found in various lengths, i.e. wound on spools or precut, of various thicknesses and materials, and having other varying characteristics, including stiffness, roughness, durability, etc. The tips of the bristles can be treated in a variety of different ways. They can all be cut to an identical height, they can be given varying heights, such as is well known, to provide a contoured or more efficient toothbrush, and they can be set into the head of the toothbrush at any of a variety of different angles or combinations of angles.
Typically, bristles on a toothbrush are bundled together, and individual bundles or clusters of bristles are then set into the head of the toothbrush handle. This procedure is well known and universally practiced, essentially to the exclusion of all others. Bundles of fibers are either stapled into the head, typically using a small metal or plastic section, or they are fused together, such as by heat, and then the bundles placed into holes on the head of a toothbrush, or the bundles are set into a mold for further processing.
Numerous designs for bristles are known to those skilled in the art. Bristles are often given a roughened surface at the tip or at other portions. A given bundle of bristles may have a rounded tip profile, or they may be cut to form an opening or cup like structure, known as a "prophy cup". The bundles of bristles may also be set into the head of the toothbrush in a certain, predetermined pattern, such as a diamond shape, rows or columns, etc. The height of the bundles of bristles can taper, be wavy, or have any other tip profile. These designs are typically constructed with the objective of improving cleaning efficiency of the brushes.
Dentists, periodontists, oral hygienists and others in the health and personal hygiene industries have long been aware of the need to provide a convenient device, such as a toothbrush, etc., to clean the interstitial and interproximal areas of the teeth and gums. Numerous picks and brushes are designed to penetrate the spaces between the gum and the tooth, as far as in needed, to clean food particles, plaque, bacteria and other foreign material from those areas, thereby improving gingival and periodontal health.
The drawbacks of the prior art are numerous. A rounded or spiked bundle of bristles may not always provide the clearance for the longest bristles to penetrate the gum/tooth interproximal areas as deeply as possible. Furthermore, the longest bristles may become worn, frayed or otherwise less than the most efficient. The typical prophy cup design suffers for the same reason--the great number of bristles around the outside of the cup often don't allow a great number of individual fibers to achieve interproximal penetration.

Filament tape for cleaning and dental application


A method of determining properties of a bonding material disposed outside of a casing in a borehole includes at least two of the following three pairs of operations: (1) inducing an acoustic wave in the casing, and measuring attenuation of the acoustic wave, by pulse-echo or other cement bond logging measurement; (2) inducing an SH wave in the casing, and measuring attenuation of the SH wave; and (3) inducing a Lamb wave in the casing, and measuring attenuation of the Lamb wave. (2) and/or (3) may be performed by an electromagnetic acoustic transducer. The method further includes determining the shear velocity or shear impedance and the compressional velocity or compressional impedance of the bonding material based on appropriate ones of the measurements. The bonding material may be cement.

In the process of extracting hydrocarbons, e.g., petroleum, from beneath the surface of the earth, wells are drilled and steel pipe (casing) is placed into the drilled hole (wellbore or borehole). Cement is then pumped into the annular space between the casing and the rock wall of the borehole (formation). The cement serves two major purposes. First, it transfers stress from the casing to the formation, increasing the effective strength and working pressure of the casing. Second, it serves to isolate vertically adjacent zones within the formation, preventing migration of liquids and gases up the wellbore between the formation and the casing, from one zone to the next. Accordingly, it is important to assure the quality of the cement both during completion of the well and during its producing life. Acoustic cement evaluation devices (cement bond logs, or CBL) conveyed by a cable (wireline) to move the tools up and down in the borehole have been the primary device to provide this assurance. The principle of evaluation is based on the loss of energy over time or distance of an acoustic wave excited in the casing. One area of conventional focus has been on determining whether cement is present outside the casing, e.g., to determine whether only fluid is present between the casing and the formation (free pipe), whether the space between the casing and the formation is filled with cement bonded to the casing (fully cemented pipe), or whether a small gap, filled with fluid, exists between the cement and casing (micro-annulus). However, conventional techniques are unable to adequately evaluate properties of the cement, such as properties indicative of the strength of the cement.

Use of Lamb and SH attenuations to estimate cement Vp and Vs in cased borehole


A method and apparatus for providing a plurality of sequential image data samples for display, is disclosed. A first one of the image data samples is accessed and then a second one of the image data samples is accessed. The first and second image data samples may then be provided for display, where one or more further data samples are provided in the event that the first and second image data samples are not contiguous. These further data samples indicate that image data samples are not available between the first and second image data samples.

Due to recent world events, security has become a very important issue. As a result, video surveillance systems are increasingly being used both commercially and privately to monitor areas for security purposes.
Within the area of video surveillance systems, networked video surveillance technologies are now being used. Unlike conventional closed circuit television (TV) systems, networked video surveillance systems make use of standard network infrastructures, such as Internet Protocol (IP) based network infrastructures, to carry digital video signals and control signals. One advantage of networked video surveillance systems is that they allow video surveillance to be performed over existing networks such as the Internet; IP based local area networks (LANs); or IP-based virtual private networks (VPNs) running on top of a public network such as the Internet.
Typically, a networked video surveillance system comprises one or more storage servers (i.e., generally implemented as a general-purpose computer as known to those in the relevant art), which receive data from one or more video camera servers distributed on a computer network. Such a networked video surveillance system also typically comprises one or more viewing devices (e.g., computers, personal digital assistants (PDA) or phones), which can be used to view live video image data from the camera servers or stored video image data from the storage servers.
Networked video surveillance systems are part of a more general class of networked viewing and recording systems that can be used to view and record image data captured from local or remote networked video cameras. Such networked viewing and recording systems can be used for a wide variety of purposes. For example, such networked viewing and recording systems can be used for security in the surveillance of buildings and vehicles.
Networked viewing and recording systems can also be used for supervision. For example, networked viewing and recording systems can be used for checking the performance of staff within a building, or for checking the performance and progress of staff of contracted companies in remote locations.
Networked viewing and recording systems can also be used for entertainment. For example, such systems can be used for live viewing of sporting events and concerts. Another example use of such a system is for education (e.g., for distance learning).
Conventional networked viewing and recording systems, such as video surveillance systems, typically allow for the display and recording of video image data uploaded to a server from one or more remote video cameras over a network, such as the Internet. Often video image data stored on such a server and associated with a particular camera is not contiguous. This can occur, for example, because recording by the particular camera has been event-triggered or scheduled for specific durations of time only. Thus, no video image data may be stored on the server for that particular camera for a particular period of time, leaving gaps in the video image data for that particular camera.
As a result, when viewing stored video image data in parallel from multiple cameras, served from such a conventional server, the video image data may not remain synchronised. This can lead to an operator mistakenly believing that a network connection has been lost or that gaps in video image data are the result of a high degree of network traffic.


An atomic absorption spectrometer is disclosed which includes a monochromater (30) and an optical path defined by a toric mirror (14), a flat mirror (16), a flat mirror (20), a flat mirror (24), a toric mirror (22) and a further toric mirror (26). The toric mirror (26) directs light through entrance slit (32) of the monochromater (30) so that radiation is reflected from diffraction grating (38) and out exit slit (40) to a detector (42). A sample stage (18) in the form of a furnace is located between the mirrors (16) and (20). The monochromater is oriented so that the entrance slit is arranged transverse to the vertical. In one arrangement, a magnifying means is also provided which magnifies an image of the aperture (32) at the sample station (18) to increase the amount of radiation which is focused at the sample stage, and which is passed through the aperture to the detector or a focusing element provided by one of the mirrors may be provided for focusing radiation at a location other than sample station (18) so an enlarged out of focus image of the entrance slit (32) is produced at the sample station (18) to increase the amount of radiation which passes through the slit and is received by the detector (42).

Atomic absorption spectrometers are well known and analyse a sample material by directing a beam of electromagnetic radiation through a sample and then detecting absorption of the beam by the sample and therefore the concentration of the sample.
Atomic absorption spectrometers usually carry a carousel of hollow cathode lamps which are selectively placed into alignment with the optical axis of the instrument to enable electromagnetic radiation of a particularly wavelength to be directed to a sample. The optical path of the instrument generally comprises an array of lenses or mirrors and a sample stage interposed in the optical path through which the electromagnetic radiation passes. Electromagnetic radiation is directed to a monochromater which includes a monochromater mirror for reflecting the radiation to a diffraction grating which reflects the radiation back to the mirror. The mirror reflects the radiation to a detector for analysis. The diffraction grating can be moved under computer control to tune the instrument to the particular wavelength which is emitted by the cathode lamp. In general, the instrument will step through a number of analysis steps, each using a different cathode lamp to provide radiation of different wavelength which passes through the sample. The diffraction grating is moved under computer control so as to reflect that wavelength back to the monochromater mirror for reflection to the detector. The absorption of that wavelength by the sample and therefore the lack of detection of that particular wavelength by the detector indicates that the sample does include atoms of a particular type which absorb that wavelength and therefore constituents of the sample can be identified.
The light which enters the monochromater passes through a vertical slit for receipt by the monochromater mirror and after reflection by the diffraction grating, and the monochromater mirror towards the detector, passes through another vertical slit to be received by the detector.
The cathode lamps which produce the radiation generally comprise a 3 mm diameter source which is directed by the optics of the instrument to focus at the sample to provide a 3 mm diameter source image at the sample. The radiation then passes to the slit in the monochromater and passes through the slit into the monochromater. Typically the slit is about 0.25 mm wide. An image of the slit or, in other words, the image which is received by the detector when focused at the source is therefore a vertical slit of about 0.25 mm width. Radiation produced by the cathode tube and which falls outside the perimeter of the slit is therefore not received by the photodetector of the spectrometer, and therefore plays no function in analysis of the sample material. Thus, a significant amount of 3 mm diameter spot of light at the sample stage is lost.
In order to provide sample material for analysis, the spectrometer includes a burner which produces a flame to ionize sample material which is introduced into the flame. The ionized sample material in general is carried up with the flame in the burner and the radiation from the cathode tube is focused in the flame at the sample position so that the radiation, more likely than not, will pass through atoms of the sample material and be absorbed. By detecting absorption of the radiation, the constituents of the sample material can be measured as is described above.
In general, because the sample is ionized in a flame, the atoms of the sample will move upwardly with the flame and will pass through the image of the slit of the monochromater at the sample stage therefore falling within the path of the radiation which passes through the source image and therefore through the slit in the monochromater for detection.
However, if other methods of producing sample material are utilized, the likelihood of the radiation from the source passing through sample atoms can be much less. For example, if sample is produced in a graphite furnace rather than a flame, there is a significant possibility that sample atoms will not locate in the source image of the slit at the sample location and therefore will not fall within the path of the radiation which is actually detected by the detector. Thus, there is a possibility that sample atoms and therefore the true constituent nature of the sample material will not be determined.
Graphite furnaces generally comprise a graphite tube of circular cross-section which is located at the sample stage. The graphite tube is open at both ends and the radiation passes through the tube. High electric current is supplied across the graphite tube to heat the graphite tube and therefore atoms of sample material which is deposited in the tube. In general, the sample material is deposited in the tube by a very thin needle which passes through an aperture or bore in the instrument and through an aperture or bore in the graphite tube. With conventional instruments, considerable skill is required in order to deposit the sample material at a correct location so that when the graphite furnace is energized, sample atoms will rise in the graphite furnace through the source image of the slit and therefore in the path of radiation which is actually detected by the detector.
If the sample material is not deposited centrally in the graphite furnace, but slightly to one side, the possibility exists that when the graphite furnace is heated, the sample atoms will travel vertically upwards and miss the source image of the slit and therefore not fall within the path of radiation which is actually detected by the detector. Thus, those sample atoms will not be detected, thereby resulting in improper or, in fact, no analysis result of the sample material.
The slit in the monochromater which allows the radiation to pass into the monochromater is required in order to block out unwanted wavelengths and also to prevent the detector from detecting extraneous radiation which may completely smother wavelengths which the detector desires to detect. In particular, with a graphite furnace, since the graphite furnace is heated to high temperature and glows white hot, the slit is required to be positioned so that it does not allow imaging of radiation produced from the graphite furnace itself onto the detector, which would otherwise saturate the detector and prevent proper analysis of radiation which passes through the sample and which is produced by the cathode tube. To prevent extraneous radiation from being detected by the detector, the size of the slit is changed depending on the wavelength being detected and also, in some instances, the slit is masked to reduce the length of the slit to ensure that radiation which is produced by the graphite furnace itself is not received by the detector.
Thus, the fact that the masked slit only allows part of the radiation which passes through the sample to enter the monochromater and the orientation of the slit can therefore greatly reduce the sensitivity of the spectrometer.


A surface acoustic wave device includes a piezoelectric substrate made of LiTaO3 and at least one interdigital transducer provided on the substrate and having a plurality of electrode fingers. The polarization direction in at least one gap portion between electrode fingers of the at least one interdigital transducer is different from the polarization direction in other gap portions between electrode fingers on the same propagation path.

1. Field of the Invention
The present invention relates to a surface acoustic wave device to be used as, for example, a resonator and a bandpass filter, a surface acoustic wave filter, and a manufacturing method for the surface acoustic wave device.
2. Description of the Related Art
In recent years, in portable telephone systems, with the increase of subscribers and diversified services, each of the frequency bands for transmission and reception has been broadened and the transmission frequencies and reception frequencies have come close to each other. Accordingly, in the bandpass filters to be used in portable telephones, it is required that the filters are broadband and that the attenuation characteristics in the vicinity of passbands are superior. When EGSM as a portable telephone system in Europe is taken as an example, the transmission side frequency band is 880 MHz to 915 MHz and the reception side frequency band is 925 MHz to 960 MHz.
Transmission signals become noise in reception side circuits. Accordingly, in the bandpass filters to be used in reception side circuits, it is necessary to make signals pass through in the band of 925 MHz to 960 MHz and to attenuate signals in the band of 880 MHz to 915 MHz. That is, the filtering characteristics having 925 MHz to 960 MHz as a passband and 880 MHz to 915 MHz as an attenuation band are required. As a result, although the pass bandwidth is required to have a broad band of 35 MHz, the frequency difference between the passband and the attenuation band is only 10 MHz.
On the other hand, in the surface acoustic wave filters used as a bandpass filter in the portable telephones, a 36xc2x0 LiTaO3 substrate is used. As for this substrate, a temperature dependence of frequency is as large as xe2x88x9230 ppm/xc2x0 C. to 35 ppm/xc2x0 C. As a result, it is necessary to provide a margin of temperature change in designing circuits including surface wave devices.
Furthermore, when frequency variations during manufacture are taken into consideration, the frequency spacing between the passband and the attenuation band becomes much narrower. Therefore, it is more important to increase the steepness of the filtering characteristic in the vicinity of the passband.
The bandwidth of a surface acoustic wave filter and the steepness in the vicinity of the passband are nearly uniquely fixed by the electromechanical coupling coefficient of a piezoelectric substrate. Generally, when the electromechanical coupling coefficient is large, broadband filtering characteristics can be obtained, and when the electromechanical coupling coefficient is small, filtering characteristics having superior steepness can be obtained.
Accordingly, when piezoelectric substrates having different electromechanical coupling coefficients are used according to elements in surface acoustic wave filters, steep and relatively broadband filtering characteristics can be obtained in accordance with these combinations.
In Japanese Unexamined Patent Application No. 7-283688, a method for adjusting electromechanical coupling coefficients is performed in such a way that in a surface acoustic wave filter of a ladder-type circuit construction, the surface wave propagation direction in a series-arm resonator is made different from that in a parallel-arm resonator. In a 36xc2x0 Y-cut LiTaO3 substrate, the electromechanical coupling coefficient is dependent on the surface wave propagation direction. When the surface wave propagation direction is supposed to be directed along the X axis, the electromechanical coupling coefficient becomes maximum, and when the surface wave propagation direction is deviated from the X axis, the electromechanical coupling coefficient becomes smaller. Accordingly, for example, in a surface acoustic wave filter having a ladder-type circuit construction, when the propagation direction in the series-arm resonator is directed along the X axis and the propagation axis in the parallel-arm resonator is deviated from the X axis, as shown in FIG. 14, the spacing between a resonant frequency and antiresonant frequency in the resonance characteristic A of the parallel-arm resonator is narrowed compared with the characteristic (shown by broken line Aa) of the case where the propagation direction of the parallel-arm resonator is not deviated from the X axis and compared with the resonance characteristic B of the series-arm resonator. Accordingly, a filtering characteristic having superior steepness can be obtained as shown by broken line in FIG. 15. Moreover, in FIG. 15, the solid line D shows the characteristic where the surface wave propagation direction is not different in the series-arm resonator and parallel-arm resonator.
On the other hand, in Japanese Unexamined Patent Application Publication No. 8-65089, a method for adding capacitance to each resonator in a surface acoustic wave filter of a ladder-type circuit construction is disclosed. When capacitance is added in parallel to a surface acoustic wave resonator, an antiresonant frequency is decreased and the spacing between a resonant frequency and antiresonant frequency is narrowed in the same way as in the case of the method disclosed in Japanese Unexamined Patent Application Publication No. 7-283688. Accordingly, it is supposed that a filtering characteristic having superior steepness can be obtained.
However, in the surface acoustic wave filters disclosed in Japanese Unexamined Patent Application Publication No. 7-283699 and Japanese Unexamined Patent Application Publication No. 8-65089, there were various problems.
For example, in the former, there was a problem that, when the propagation direction of a surface wave is deviated from the X axis in a 36xc2x0 Y-cut LiTaO3 substrate, the power flow angle as an angular difference between the direction of travel of the surface wave and the direction of the energy transfer increases, the leakage of energy from the waveguide increases, and the loss increases. Furthermore, since it is necessary to provide a plurality of surface acoustic wave resonators having different propagation directions on the same piezoelectric resonator, the size of a surface acoustic wave filter is greatly increased. Furthermore, there were cases that different resonators are acoustically partially coupled and because of the coupling the characteristics become deteriorated.
On the other hand, in the method described in Japanese Unexamined Patent Application Publication No. 8-65089, in order to add capacitance, the chip size was greatly increased. Furthermore, because the filtering characteristics cannot be changed after the electrodes have been formed, the frequency could not be adjusted.
In order to overcome the problems described above, preferred embodiments of the present invention provide a surface acoustic wave device in which the above-mentioned drawbacks of the prior art are solved and without causing a larger size, increased loss, and deteriorated characteristics, such that the steepness in the vicinity of the passband is superior when used as a bandpass filter, and provide a manufacturing method for such a surface acoustic wave device.
Other preferred embodiments of the present invention provide a surface acoustic wave filter which is characterized by low loss, excellent filtering characteristics, very small size, and superior steepness in the vicinity of the passband.
According to a preferred embodiment of the present invention, a surface acoustic wave device includes a piezoelectric substrate made of LiTaO3, and at least one interdigital transducer disposed on the substrate and having a plurality of electrode fingers. The polarization direction in at least one gap portion between electrode fingers of the at least one interdigital transducer is different from the polarization direction in other gap portions between electrode fingers on the same propagation path.
According to the unique structure and arrangement of this preferred embodiment of the present invention, the electromechanical coupling coefficient is greatly reduced compared with the case where the polarization direction of all the gap portions in the interdigital transducer is the same. Thus, a frequency spacing between a resonant frequency and an antiresonant frequency is greatly narrowed and, when used as a surface acoustic wave filter, the steepness in the vicinity of the passband is greatly increased.
In the surface acoustic wave device, the electrode fingers of the at least one interdigital transducer may be withdrawn so that the electromechanical coupling coefficient is reduced by the withdrawing. In this case, the spacing between a resonant frequency and an antiresonant frequency can be much more reduced, and, when used as a surface acoustic wave filter, the steepness of filtering characteristics in the vicinity of the passband can be much more increased.
According to another preferred embodiment of the present invention, a surface acoustic wave filter preferably includes a piezoelectric substrate, and a plurality of one-port surface acoustic wave elements each having an interdigital transducer which is disposed on the piezoelectric substrate. The plurality of one-port surface acoustic wave elements are arranged to define a ladder-type circuit having at least one parallel-arm resonator and at least one series-arm resonator. The polarization direction in at least one gap portion between electrode fingers in the interdigital transducer of one of the one-port surface acoustic wave elements is different from the polarization direction in other gap portions between the electrode fingers.
According to still another preferred embodiment of present invention, a surface acoustic wave resonator filter includes a piezoelectric substrate, and a plurality of interdigital transducers provided on the piezoelectric substrate. The polarization direction in at least one gap portion between electrode fingers in the interdigital transducer of one of the one-port surface acoustic wave elements is different from the polarization direction in other gap portions between the electrode fingers.
According to these unique structures and arrangements, the frequency spacing between a resonant frequency and an antiresonant frequency is narrowed in the at least one surface acoustic wave element. Accordingly, the steepness in the vicinity of the passband of the surface acoustic wave filter is greatly increased.
For example, in a parallel-arm resonator, when the polarization direction in at least one gap portion is different from the polarization direction in other gap portions as described above, the resonant frequency is increased in the parallel-arm resonator and the steepness of the filtering characteristic on the lower frequency side of the passband is increased. Furthermore, in a series-arm resonator, when the polarization direction in gap portions is different from each other as described above, the steepness on the higher frequency side of the passband of a surface acoustic wave filter is greatly increased.
In the filters, a portion of the electrode fingers of the at least one interdigital transducer may be withdrawn. Alternatively, the propagation direction of a surface acoustic wave in at least one of the interdigital transducers may be different from the propagation direction of other interdigital transducers.
In this case, the electromechanical coupling coefficient of the surface acoustic wave device is substantially decreased by the thinning-out process, and the steepness of filtering characteristics can be more effectively increased.
The manufacturing method for a surface acoustic wave device including a piezoelectric substrate and at least one interdigital transducer provided on the substrate and having a plurality of electrode fingers preferably includes the steps of forming at least one of the interdigital transducers on the piezoelectric substrate and applying a DC voltage so that an electric field strength of about 50 V/xcexcm or more is applied to the at least one interdigital transducer. In the case, frequency adjustment may also performed by applying the DC voltage.
For the purpose of illustrating the invention, there are shown in the drawings several forms that are presently preferred, it being understood, however, that the invention is not limited to the precise arrangements and instrumentalities shown.
Other elements, features, characteristics and advantages of the present invention will become more apparent from the following detailed description of preferred embodiments thereof with reference to the attached drawings.

Surface acoustic wave device, surface acoustic wave filter, and manufacturing method for the surface acoustic wave device


The present invention relates to a packet routing apparatus for routing packets via a pre-established connection in a store and forward network. It is an object of the present invention to realize adaptability to a desired redundant configuration and to avoid degradation in transmission efficiency during a reconfiguration period at low cost and with reliability. In order to achieve the object, the present invention is composed of a routing section for storing inputted packets and routing the packets according to route selection information conforming to the pre-established connection, and a plurality of control sections being arranged redundantly, for controlling the routing section according to a system configuration which conforms to a standby redundancy method, and allowing the operation of the routing section in a reconfiguration process while delivering information necessary for continuing the control to a part which inherits the control.

1. Field of the Invention
The present invention relates to a packet routing apparatus for routing packets via a pre-established connection in a node in a store and forward network.
2. Description of the Related Art
In recent years, a packet transmission technique has been applied to wide area networks such as the Internet, mobile communication networks, and others, which enables provisions of various data communication services through these wide area networks. As a result, the number of terminals receiving such data communication services has been rapidly increasing.
In the above-mentioned wide area networks, MPLS (Multiprotocol Label Switching) is being actively employed, the MPLS capable of not only setting and selecting a path but also high-speed traffic monitoring and controlling based on, for example, 'a label used for identification', which is added to an IP packet.
Further, MPLS is a major technique for realizing traffic engineering, VPN (Virtual Private Network), and so on, therefore, it has been actively standardized and improved.
FIG. 5 is a view showing a configuration example of a packet routing apparatus disposed in an MPLS network.
In FIG. 5, packet routing apparatuses 20-1, 20-2 are disposed as nodes in the MPLS network in which, for example, a connection oriented label path is formed when necessary.
The packet routing apparatus 20-1 is composed of the following elements:                duplex primary controlling parts 30-11, 30-12; and        a relay processing part 40-1 operating under the control of these primary controlling parts 30-11, 30-12 and connected to a preceding transmission section and a subsequent transmission section in the MPLS network.
The primary controlling part 30-11 is composed of the following elements:                a main processor 31-11;        an external interfacing part 33-11, a nonvolatile memory 34-11, and a routing table 35-11 which are connected to an internal bus 32-11 together with the main processor 31-11; and        a branch interfacing part 36-11 connected to the aforesaid internal bus 32-11 and connected to a corresponding I/O terminal of the relay processing part 40-1 while being directly connected to a branch interfacing part 36-12 provided in the primary controlling part 30-12.
Incidentally, since the configuration of the primary controlling part 30-12 is the same as the configuration of the primary controlling part 30-11, a common reference numeral with '2' added thereto as a second suffix number is hereinafter assigned to each of corresponding components, and the explanation thereof will be omitted here.
The relay processing part 40-1 is composed of the following elements:                a submodule 41-1P connected to corresponding I/O terminals of the aforesaid branch interfacing parts 36-11, 36-12;        a submodule 41-1S connected to the other I/O terminals of the branch interfacing parts 36-11, 36-12;        a line accommodation part 42-1P operating under the control of the submodule 41-1P and connected to the aforesaid preceding transmission section; and        a line accommodation part 42-1S operating under the control of the submodule 41-1S and connected to the aforesaid subsequent transmission section.
The submodule 41-1P is composed of the following elements:                a network processor 43-1P; and        a CAM 44-1P, a buffer memory 45-1P, and an I/O processor (IOP) 46-1P which are accessed by the network processor 43-1P.
Incidentally, since the configuration of the submodule 41-1S is the same as the configuration of the submodule 41-1P, a common reference numeral with 'S' added thereto as a second suffix symbol is hereinafter assigned to each of corresponding components, and the explanation thereof will be omitted here.
In the conventional example as configured above, either one of the primary controlling parts 30-11, 30-12 (assumed to be denoted by the reference numeral '30-11' here for simplicity) operates as an active system according to a system configuration externally designated and the other one stands by as a standby system to operate based on standby redundancy.
In the primary controlling part 30-11 operating as the active system, the main processor 31-11 obtains route selection information (a part or all thereof may be given as a default value such as an initial value or others) based on a predetermined routing protocol, stores the route selection information in the routing table 35-11 in a form, for example, shown in FIG. 6, and updates the route selection information based on this routing protocol or other protocols when necessary (FIG. 7 (1)).
Further, every time the contents of the routing table 35-11 are thus set or updated, the main processor 31-11 transfers updated information among these contents to both of the submodules 41-1P, 41-1S or either one of them via the branch interfacing part 36-11 (FIG. 7 (2)).
The parts in the submodule 41-1P (41-1S) cooperate with one another in the following manner.                The network processor 43-1P (43-1S) stores the route selection information thus notified by the main processor 31-11 in the CAM 44-1P (44-1S) (FIG. 7 (3)).        The line accommodation part 42-1P (42-1S) physically interfaces with the preceding transmission section and physically receives each packet given thereto via the preceding transmission section (FIG. 7 (4)).        The I/O processor 46-1P (46-1S) plays a leading role in storage management involved in a write operation onto a first storage area of the buffer memory 45-1P (45-1S), and stores thus received packets in the first storage area in sequence under the storage management (FIG. 7 (5)).
Further, the network processor 43-1P (43-1S) plays a leading role in storage management involved in a read operation from the first storage area of the buffer memory 45-1P (45-1S), and reads the packets precedingly stored in this first storage area under the storage management based on first in first out to route each of the packets based on the following procedure.                It is judged whether or not a packet in question can be routed based on the route selection information stored in the CAM 44-1P (45-1S) (hereinafter, referred to as 'routable/nonroutable judgment') (FIG. 7 (6)).        This packet is delivered to the submodule 41-1S (41-1P) when the result of this routable/nonroutable judgment is true.        When, on the other hand, the result of the above routable/nonroutable judgment is false, the packet in question is temporarily held (hereinafter, referred to as a 'primary preserved packet') and this primary preserved packet is delivered to the main processor 31-11 via the branch interfacing part 36-11 and the internal bus 32-11 (FIG. 7 (7)).
The main processor 31-11 obtains route selection information to be applied to the routing of this primary preserved packet (hereinafter, referred to as 'additional route selection information') out of the route selection information stored in the routing table 35-11 (FIG. 7 (8)), and delivers this additional route selection information to the submodule 41-1P (41-1S) via the internal bus 32-11 and the branch interfacing part 36-11 (FIG. 7 (9)).
In the submodule 41-1P (41-1S), the network processor 43-1P (43-1S) processes the following.                to store the delivered additional route selection information in a vacant area of the CAM 44-1P (44-1S) (FIG. 7 (10))        to deliver the aforesaid primary preserved packet to the submodule 41-1S (41-1P), considering the result of the aforesaid 'routable/nonroutable judgment' to be true (or after performing the 'routable/nonroutable judgment' again and identifying the result thereof as true) (FIG. 7 (11))
Meanwhile, in the submodule 41-1S (41-1P), the network processor 43-1S (43-1P) plays a leading role in storage management involved in a write operation onto a second storage area of the buffer memory 45-1S (45-1P), and stores the packet delivered from the opposite submodule 41-1P (41-1S) in the aforesaid manner, in this second storage area in sequence under the storage management.
The I/O processor 46-1S (46-1P) processes the following.                to play a leading role in storage management involved in a read operation from the aforesaid second storage area, and sequentially read each packet stored in this second storage area based on first in first out under the storage management        to judge whether or not the packet in question can be routed based on the route selection information stored in the CAM 44-1S (44-1P) (hereinafter, referred to as 'routable/nonroutable judgment') (FIG. 7 (12))        to transmit this packet to the subsequent transmission section via the line accommodation part 42-1S (42-1P) when the result of this routable/nonroutable judgment is true (FIG. 7 (13))        when, on the other hand, the result of the above routable/nonroutable judgment is false, to temporarily maintain the packet in question (hereinafter, referred to as a 'secondary preserved packet') and to deliver this packet to the main processor 31-11 via the branch interfacing part 36-11 and the internal bus 32-11 (FIG. 7 (14))
Incidentally, since the processing, which is performed by the main processor 31-11 according to thus delivered packet, of giving the additional route selection information is the same as the aforesaid processing (FIG. 7 (8), (9)) except that neither a supply source of this packet nor a destination of the additional route selection information is the network processor 43-1P (43-1S) but both of them are the I/O processor 46-1S (46-1P), the explanation thereof will be omitted here.
The parts in the submodule 41-1S (41-1P) cooperate with one another in the following manner.                The I/O processor 46-1S (46-1P) plays a leading role in the storage management involved in the read operation from the second storage area of the buffer memory 45-1S (45-1P) and reads, under the storage management, the secondary preserved packet delivered in the above-described manner (FIG. 7 (15)).        The line accommodation part 42-1S (42-1P) physically interfaces with the subsequent transmission section and transmits this secondary preserved packet to this subsequent transmission section (FIG. 7 (16)).
Further, when some event occurs and the primary controlling part 30-11 as the active system is not allowed to operate (FIG. 7 (20)), the parts in the primary controlling part 30-12 which have been on standby as the standby system cooperate with one another in the following manner prior to the start of the aforesaid 'operation as the active system' according to the system configuration.                The main processor 31-12 provided in the primary controlling part 30-12 cooperates with an adjacent packet routing apparatus 20-2 based on a prescribed communication protocol via the relay processing part 20-1 and the subsequent transmission section to establish a new connection with this packet routing apparatus 20-2 (FIG. 7 (21)).        The main processor 31-12 obtains (generates) the route selection information consistent with this connection (FIG. 7 (22)) to store the route selection information in the routing table 35-12 and to deliver the route selection information to the submodule 41-1P (41-1S) via the branch interfacing part 36-12 (FIG. 7 (23)).
In the submodule 41-1P (41-1S), the network processor 43-1P (43-1S) stores the delivered route selection information in the CAM 44-1P (44-1S) (FIG. 7 (24)).
Further, the main processor 31-12 cooperates with the line accommodation part 42-1P (42-1S) via the branch interfacing part 36-12 and the submodule 41-1P (41-1S) to control the operation of each of the parts in the primary controlling part 30-12 which is to operate as the active system in place of the primary controlling part 30-11 (FIG. 7 (25)).
Therefore, the duplex primary controlling parts (30-11, 30-12) (30-21, 30-22) provided in the packet routing apparatuses 20-1, 20-2 operate based on the standby redundancy to form and maintain a desired label path between these packet routing apparatuses 20-1, 20-2 with high reliability.
In the above-described conventional example, when some event occurs, requiring the updating of the system configuration, it takes a long time as several ten seconds to establish such connection, which enables the 'primary controlling part which has been the standby system' to start operation as the active system, because a formation of a new connection needs to be done in a complex way as described above.
Accordingly, even when the primary controlling parts 30-11, 30-12 are redundantly arranged, useless increase in transmission delay and degradation in service quality are caused in the process of updating the system configuration.
Moreover, in order to update the system configuration based on active redundancy on a TCP layer, it is generally necessary to constantly deliver between the active system and the standby system and refer to, as common information, not only the states of the system in which the updating is performed based on the TCP protocol but also various information associated with the states.
Frequent information exchange between these active system and standby system, however, excessively increases an average throughput required for controlling the communication protocol, thereby causing an unnecessarily dense connection between these systems (connection involving hardware and/or software), which highly possibly results in reliability degradation and great increase in running cost.
Further, the total reliability and transmission quality of the system greatly depend on the performance and throughput of a module realizing the TCP so that remaining bugs are not allowable, and a complex configuration and a scale increase have to be avoided as much as possible.
Incidentally, each duplex primary controlling parts' sharing all the resources can avoid or substantially reduce the aforesaid complex way of formation of the new connection, increase in the transmission delay, and degradation in the service quality.
The aforesaid processing performed by the primary controlling parts 30-11, 30-12, however, is realized as application systems operating under separate operating systems which are not provided with any supporting function of sharing the resource therebetween.
Further, in order to satisfy strict demands concerning both reduction in man-hour required for development and securing of reliability, for example, an existing module such as API (Application Program Interface) or the like such as 'socket interface' which easily realizes interprocess communication as well as an access to a file is actively incorporated into such application systems.
Consequently, the application of an operating system enabling the aforesaid delivery and sharing of the resources is technically possible but difficult in actual practice due to restriction on cost.

Packet routing apparatus for routing packets via a pre-established connection in a store and forward network


A code excited linear predictive coder and decoder well suited to speech recording, transmission and reproduction, especially in voice messaging systems, provides backward adaptive gain control of stored codevectors to be applied to a synthesis filter prior to being compared with sequences of input speech signals. Simplified linear predictive parameter quantization using efficient table lookup procedures, efficient codevector storage and search all contribute in an illustrative embodiment to high quality coding and decoding with reduced computational complexity.

Recent advances in speech coding coupled with a dramatic increase in the performance-to-price ratio for Digital Signal Processor (DSP) devices have significantly improved the perceptual quality of compressed speech in speech processing systems such as voice store- and-forward systems or voice messaging systems. Typical applications of such voice processing systems are described in S. Rangnekar and M. Hossain, "AT&T Voice Mail Service," AT&T Technology, Vol. 5, No. 4, 1990 and in A. Ramirez, "From the Voice-Mail Acorn, a Still-Spreading Oak," NY Times, May 3, 1992.
Speech coders used in voice messaging systems provide speech compression for reducing the number of bits required to represent a voice waveform. Speech coding finds application in voice messaging by reducing the number of bits that must be used to transmit a voice message to a distant location or to reduce the number of bits that must be stored to recover a voice message at some future time. Decoders in such systems provide the complementary function of expanding stored or transmitted coded voice signals in such manner as to permit reproduction of the original voice signals.
Salient attributes of a speech coder optimized for transmission include low bit rate, high perceptual quality, low delay, robustness to multiple encodings (tandeming), robustness to bit-errors, and low cost of implementation. A coder optimized for voice messaging, on the other hand, advantageously emphasizes the same low bit rate, high perceptual quality, robustness to multiple encodings (tandeming) and low cost of implementation, but also provides resilience to mixed-encodings (transcoding).
These differences arise because, in voice messaging, speech is encoded and stored using mass storage media for recovery at a later time. Delays of up to a few hundred milliseconds in encoding or decoding are unobservable to a voice messaging system user. Such large delays in transmission applications, on the other hand, can cause major difficulties for echo cancellation and disrupt the natural give-and-take of two-way real time conversations. Furthermore, the high reliability of mass storage media achieve bit error rates several orders of magnitude lower than those observed on many contemporary transmission facilities. Hence, robustness to bit errors is not a primary concern for voice messaging systems.
Prior art systems for voice storage typically employ the CCITT G.721 standard 32 kb/s ADPCM speech coder or a 16 kbit/s Sub-Band coder (SBC) as described in J. G. Josenhans, J. F. Lynch, Jr., M. R. Rogers, R. R. Rosinski, and W. P. VanDame, "Report: Speech Processing Application Standards," AT&T Technical Journal, Vol. 65, No. 5, September/October 1986, pp. 23-33. More generalized aspects of SBC are described, e.g., in N. S. Jayant and P. Noll, "Digital Coding of Waveforms-Principles and Applications to Speech and Video", and in U.S. Pat. No. 4,048,443 issued to R. E. Crochiere et al. on Sep. 13, 1977.
While 32 kb/s ADPCM gives very good speech quality, its bit-rate is higher than desired. On the other hand, while 16 kbit/s SBC has half the bit-rate and has offered a reasonable tradeoff between cost and performance in prior art systems, recent advances in speech coding and DSP technology have rendered SBC less than optimum for many current applications. In particular, new speech coders are often superior to SBC in terms of perceptual quality and tandeming/transcoding performance. Such new coders are typified by so-called code excited linear predictive coders (CELP) disclosed, e.g., in U.S. patent application Ser. No. 07/298,451, by J-H Chen, filed Jan. 17, 1989, now abandoned, and U.S. patent application Ser. No. 07/757,168 by J-H. Chen, filed Sep. 10, 1991, U.S. patent application Ser. No. 07/837,509 by J-H. Chen et al., filed Feb. 18, 1992, and U.S. patent application Ser. No. 07/837,522 by J-H. Chen et al., filed Feb. 18, 1992, assigned to the assignee of the present application. Each of these applications are hereby incorporated by reference in the present application as if set forth in their entirety herein. Related coders and decoders are described in J-H Chen, "A robust low-delay CELP speech coder at 16 kbit/s," Proc. GLOBECOM, pp. 1237-1241 (November 1989); J-H Chen, "High-quality 16 kb/s speech coding with a one-way delay less than 2 ms," Proc. ICASSP, pp. 453-456 (April 1990); J-H Chen, M. J. Melchner, R. V. Cox and D. O. Bowker, "Real-time implementation of a 16 kb/s low-delay CELP speech coder," Proc. ICASSP, pp. 181-184 (April 1990); all of which papers are hereby incorporated herein by reference as if set forth in their entirety. A further description of the candidate 16 kbit/sec LD CELP standard system was presented in a document entitled "Draft Recommendation on 16 kbit/s Voice Coding," (hereinafter the Draft CCITT Standard Document) submitted to the CCITT Study Group XV in its meeting in Geneva, Switzerland during Nov. 11-22, 1991 which document is incorporated herein by reference in its entirety. In the sequel, systems of the type described in the Draft CCITT Standard Document will be referred to as LD-CELP systems.

Method of use of voice message coder/decoder


A pair of clamping arms of a wire clamper used in a wire bonding apparatus being opened and closed via the electric strain effect or magnetic strain effect of a piezoelectric element. With the use of a piezoelectric element that expands when energized to open the clamping arms so as to release the wire held by the clamping arms, the overall weight of the wire clamper can be small, a quick clamping action is secured and the clamping force which is easily adjustable can be steady at a set value.

1. Field of the Invention
The present invention relates to a wire clamper used in a wire bonding apparatus.
2. Prior Art
Japanese Patent Application Publication (Kokoku) No. 61-2294 discloses one of the conventional wire clampers.
This wire clamper includes a movable arm and a fixed arm. The movable arm is urged toward the fixed arm by a spring, and the movable arm is opened and closed by a solenoid. When the solenoid is energized, the movable arm is pushed by the projecting rod of the solenoid, overcoming the driving force of the spring. The movable ar is thus opened. When the power to the solenoid is cut off, the movable arm is closed by the spring, thus holding the wire between the movable arm and the fixed arm.
Since this prior art clamper uses a solenoid to open and close the arm parts of the clamper, there are several problems. The overall weight of the clamper tends to be heavy, and the clamping action or the response of the clamper is slow. In addition, since the load which retains the wire (i. e., the clamping load) is obtained by the driving force of the spring, which is approximately 40 to 50 g, the movable arm tends to be unsteady when the bonding head moves at high speed. This means that the clamping load is unstable. Moreover, since the clamping load is obtained by the spring, the spring must be replaced when the amount of clamping load needs to be changed. In addition, a desired clamping load is usually not obtained easily, and the adjustment of the clamping load requires a considerable amount of time.