A motor includes a stator and a rotor. The rotor is relative to the stator, and has a rotation axis. A magnet and a magnetic-material member magnetically interact with each other. The magnet and the magnetic-material member are provided for enabling the stator and the rotor to magnetically attracting each other. The magnet has a shape of a ring, and is coaxial with the rotation axis. The magnet has an inner circumference and an outer circumference. The inner circumference and an outer circumference have a common center. The magnet has a plurality of N and S poles alternately arranged along a circumferential direction thereof. At least one of boundaries between the N and S poles extends on a straight line out of the common center. A method of manufacturing the motor, and a method of magnetizing a raw member for the magnet are also disclosed.

1. Field of the Invention
This invention generally relates to a motor, a method of manufacturing a motor, and a method of magnetizing a raw member for a magnet in a motor to make the magnet. This invention particularly relates to a magnetizing method, and a motor and its manufacturing method which are designed so that a rotor and a stator magnetically attract each other to provide improved rotation characteristics of the motor.
2. Description of the Related Art
A typical optical disc drive contains a motor for rotating and driving an optical disc. A general laser beam printer (LBP) contains a motor for rotating and driving a polygon mirror. Such motors are required to have extremely stable rotation characteristics.
There are small-sized portable optical disc devices having optical disc drives respectively. In general, such an optical disc device is required to normally operate regardless of the position or attitude of a device body. The position of a motor in the optical disc device depends on that of the device body.
In some cases, a motor in an LBP is in an unusual position to implement the miniaturization of the LBP body. A first example of the unusual position is such that the rotary shaft (the spindle) of the motor tilts relative to the main walls of the LBP casing. A second example of the unusual position is called an inverted position where the rotary shaft of the motor may fall out of its support bearing due to its weight (the rotor is closer to the ground than the stator is).
Accordingly, motors are requested which exhibit stable rotation performances regardless of their positions or attitudes.
In the event that the rotor of a motor in an optical disc drive develops a whirl (an undesirable deflection) due to unsteady support of the rotary shaft of the motor or floats in a direction of slipping out of a related bearing during operation of the motor, the ability of the optical disc drive to read and write information from and on an optical disc is impaired. When a motor in an LBP has a similar problem, the printing performance of the LBP is decreased.
Japanese patent application publication number 2002-281712 discloses a disc driving motor designed to prevent the occurrence of a whirl. The motor in Japanese application 2002-281712 includes a magnet which is designed to attract the rotor of the motor toward the stator to enhance the rotation characteristics of the motor.
Specifically, in the motor of Japanese application 2002-281712, an annular back yoke is fixed to a step on an outer circumferential portion of a bearing holder in a stator side, and an annular bias magnet is bonded to a surface of the back yoke which faces a rotor side. The circumferential-direction magnetic pole width (angular range) of the bias magnet is made uneven. Thereby, an edgewise pressure (a side pressure) is applied to a spindle. A rotor yoke in the rotor side which is opposed to the bias magnet is magnetically attracted toward the stator side so that an undesirable clearance between the spindle and a related bearing can be removed. Therefore, it is possible to prevent the occurrence of a whirl. Furthermore, it is possible to stably maintain the rotation of the rotor at high speeds.
As will be explained later, it is desirable to improve the motor of Japanese application 2002-281712.

Magnetizing method, and motor and method of manufacturing motor


A method of forming an aluminum contact including forming a barrier metal layer on an interlayer insulation layer pattern defining a contact hole, and forming an aluminum layer on the barrier metal layer so as to fill the contact hole. The method further includes forming a photoresist pattern for ion implantation, implanting ions into the aluminum layer, and annealing by using a rapid thermal process.

(a) Field of the Invention
The present invention relates to a method of manufacturing semiconductor devices. More particularly, the present invention relates to a method for forming an aluminum contact in a semiconductor device.
(b) Description of the Related Art
As semiconductor devices have been more highly integrated, width and thickness of metal lines therein have been reduced, and size of a contact has been reduced. Therefore, an aspect ratio of a contact hole has been increased, and thus a method for fully filling the contact hole has become very important.
For a method for fully filling the contact hole having a high aspect ratio with a low resistivity material, an aluminum layer may be deposited by a chemical vapor deposition (CVD) process, so-called Al-CVD.
The Al-CVD process is classified as a blanket deposition process or a selective deposition process. The blanket deposition process is a method of filling a contact hole by depositing an aluminum film on an entire surface of a wafer. This process is for making the best of a good step-coverage of the aluminum film. However, the blanket deposition process of Al-CVD may have an abnormal growth characteristic in a thick aluminum film. Consequently, the film may have a rough surface and may fail to fill a small contact due to blocking of an inlet portion.
On the other hand, the selective deposition process is a method for making use of a difference of a growth rate depending on a substrate (e.g., an insulation layer or a conductive layer) whereon the deposition is performed. This process can be used for a limited region such as a via contact, but it has a difficulty in forming a metal contact wherein a barrier metal is pre-deposited.
Japanese Patent Publication No. 1992-171940 describes a manufacturing method of a semiconductor device including steps of forming conductive layers having an ohmic conductive layer and a barrier conductive layer and a aluminum layer (or aluminum alloy layer) in a contact hole, leaving the aluminum layer in a sidewall of the contact hole, leaving the barrier conductive layer on the bottom of the contact hole, reflowing the aluminum layer in a sidewall of the contact hole, and forming an additional aluminum layer to fill the contact hole. Additionally, U.S. Pat. No. 6,022,800 describes a method of filling a contact hole including steps of forming a first TiN layer on an entire surface of a contact hole by a CVD method, forming a second TiN layer thereon by a physical vapor deposition (PVD), and forming a tungsten layer so as to fill the contact hole. Furthermore, Japanese Patent Publication No. 1998-64902 describes a method of a filling a contact hole including steps of forming a barrier layer of Ti and TiN by a PVD method, forming a Ti layer on the barrier layer, forming an aluminum layer at room temperature, and reflowing the aluminum layer by a thermal process.
As the line width in a circuit becomes narrower, conventional deposition methods for aluminum wiring in a semiconductor device face limitations. Accordingly, a method for filling a contact hole (a contact between a lower conductive layer and an upper aluminum line) or a via hole (a contact between a lower aluminum line and an upper aluminum line) has become a critical technology for an electrical interconnection.
In filling the contact hole or via hole (referred to as only "contact hole" hereinafter) with aluminum, various process methods have been developed so as to have better electrical characteristics and better filling characteristics. In manufacturing a next generation memory device, the contact hole has a high aspect ratio, so a PVD method (i.e., a sputtering method) becomes insufficient for a deposition process for forming a metal layer having a line width of under 0.25 μm. Therefore, various types of research are under investigation for forming an aluminum layer using a CVD method having a better step coverage characteristic than the PVD method. Particularly, a process is under investigation wherein an aluminum thin film is selectively formed in a contact hole by a CVD method and an additional aluminum layer is deposited on an exterior part of the contact hole.
FIG. 1A and FIG. 1B are cross-sectional views showing principal stages of forming an aluminum contact according to a conventional method.
First, as shown in FIG. 1A, an active region is defined on a silicon wafer 101 by a field oxide layer (not shown). The field oxide layer is formed by using a local oxidation of silicon (LOCOS) process or a trench process. A gate oxide layer 104 is formed on the silicon wafer 101 by a thermal oxidation process. Subsequently, a polysilicon layer 106 to be used as a gate electrode is formed on the gate oxide layer 104, and the polysilicon 106 and the gate oxide layer 104 are patterned to a predetermined width.
Then, a lightly doped drain (LDD) 103 is formed in an active region on the silicon wafer 101 by implanting P-type or N-type dopants having a low concentration thereinto by using the gate electrode 106 as an implantation mask. After a liner layer 107 and a sidewall 105 is sequentially formed on both side of the gate stack including the oxide layer 104 and the gate electrode 106, a source/drain 102 is formed in an active region on the silicon wafer 101 by implanting the same type of dopants as the LDD 103 thereinto by using the sidewall 105 and gate electrode 106 as an implantation mask.
Subsequently, after a capping oxide layer 108 is formed on the upper surface of the substrate, a pre-metal dielectric (PMD) layer 109 composed of ozone-TEOS or high density plasma phosphosilicate glass (HDP-PSG) is thickly formed by an atmospheric pressure CVD (APCVD) method. After a heat treatment process for improving the hardness of the PMD layer 109, the upper surface of the PMD layer is planarized by chemical mechanical polishing (CMP). Then, a capping oxide layer 110 is formed on the PMD layer 109.
After a photosensitive layer pattern (not shown) for patterning a contact hole is formed on the capping oxide layer 110, as shown in FIG. 1B, the contact hole is formed by etching the exposed capping oxide layer 110 by using the photosensitive layer pattern as a etching mask. The contact hole is filled by depositing a TiN layer 111 as a barrier metal layer on the entire surface over the silicon wafer 101 and subsequently forming a tungsten layer 112.
A tungsten layer formed by a CVD method has relatively low resistivity. In addition, tungsten is a heavy metal having high immunity against electron migration and stress migration, and thus the tungsten layer may be free from voids or hillocks that may cause a junction breakdown. However, as the integration of semiconductor devices become higher, a metal having a low resistivity is highly required. Aluminum having a low resistivity has a difficulty in suppressing a hillock, and thus junction breakdown may occur.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form a part of the prior art with respect to the present invention.


A measurement circuit including: a memory, and a processor coupled to the memory and configured to measure a first signal strength of a received signal within a first frequency band, the received signal including a signal transmitted from a first transmitting apparatus within the first frequency band and a signal transmitted from a second transmitting apparatus within a second frequency band that constitutes a part of the first frequency band, to generate a second signal strength of the signal transmitted from the second transmitting apparatus within the second frequency band, and to generate a third signal strength of the received signal within the second frequency band based on the first signal strength and the second signal strength.

in the related arts, a technology is known by which reception electric field strength that is corrected depending on characteristic change due to variation of temperature and variation of power-supply voltage is detected in a mobile wireless communication device (for example, see Japanese Laid-open Patent Publication No, 7-35809).
In recent years, a mobile communication system using orthogonal frequency division multiple access (OFDMA) having high spectrum efficiency has been put to practical use in order to cope with an increase in a data amount of wireless communication. For example, as a mobile phone system, standards of Long Term Evolution (LTE) have been developed in 3rd generation partnership project (3GPP).
In LTE, OFDMA is used in a downlink that corresponds to communication from a base station to a wireless terminal, in addition, single carrier-frequency division multiple access (SC-FDMA) is used in an uplink that corresponds to communication from a wireless terminal to a base station.
In LTE, when a plurality of base stations exists, handover is used by which a wireless terminal is coupled to an optimal base station. The wireless terminal periodically detects a neighboring cell (cell is the area in which communication with a base station is allowed to be performed) while communicating with a base station to which the wireless terminal is being coupled and reports reception quality of the cell to the base station to which the wireless terminal is being coupled. That procedure is called "Measurement". The base station that receives the report from the wireless terminal selects an optimal cell from a list of cells and the reception qualities, and executes processing of changing the base station that is a connection destination. That procedure is called "Hand-over".
As the reception quality that is reported to the base station, for example, there is reference signal reception power (RSRP) and reference signal reception quality (RSRQ). The RSRQ is calculated from the RSRP and a received signal strength indicator (RSSI). The RSRP and the RSSI are measured using a received signal of an OFDM symbol that includes a reference signal (RS) that is transmitted in a downlink.
For example, in a definition of 3GPP, an RSSI is defined as an average value of the total reception power (serving cell, neighboring cell, thermal noise, and the like) that are observed in OFDM symbols that include RSs on the certain number of resource blocks. As a method of measuring such an RSSI, there is a time domain method of measuring an RSSI in a time domain and a frequency domain method of measuring an RSSI in a frequency domain.

Measurement circuit, wireless communication device, and measurement method


A tombstone fixture for supporting workpieces has a stiffened tooling column.

Tombstone fixtures are widely used for supporting one or more workpieces clamped against faces of the fixture, while the workpieces are machined. This basic fixture generally comprises a tooling column rising from a fixture base, and the base is adapted to fit a machine support surface, such as a machining center table. In many production environments, the fixtures are affixed to the top surface of interchangeable machine pallets which have common registration and clamping surfaces mated to master machine registration and clamping surfaces. Also, the fixtures are often provided with permanent locating and clamping hardware, and are said to be "dedicated" to the production of a specific part. Several examples of prior art tombstone fixture configurations are depicted in FIGS. 1a-d, herein. FIGS. 1a and 1b are four-sided fixtures, with FIG. 1a being solid, and FIG. 1b being hollow. FIGS. 1c and 1d are T-type fixtures, each resembling an inverted T, with FIG. 1c being solid, and FIG. 1d being "windowed" by a through aperture. An example of a tombstone fixture fully rigged with clamping and locating hardware for supporting a plurality of workpieces during machining operations is shown in U.S. Pat. No. 5,454,148, of G. A. Ewer, et al, issued Oct. 3, 1995, entitled Tombstone Fixture. Further examples of tombstone fixtures are shown in U.S. Pat. No. 3,790,153, of H. Seidenfaden, issued Feb. 5, 1974, entitled Equipment for Holding Workpieces, and U.S. Pat. No. 4,630,811, of C. D. Rudisill, issued Dec. 23, 1986, entitled Modular Fixturing Apparatus. Examples of interchangeable machine pallets are shown in U.S. Pat. No. 4,468,019, of S. Staudenmaier, issued Aug. 28, 1984, entitled Pallet Clamping System for Machine Tools, and U.S. Pat. No. 4,512,068, of T. W. Piotrowski, issued Apr. 23, 1985, entitled Pallet Receiver with Compliant Pin and Socket Registration.
In machines for performing operations on a workpiece, especially those operations where stock is removed from the workpiece, vibrations are frequently generated. One such machine for removing stock is a CNC machining center, which is a machine for milling, drilling, etc., in an automatic cycle, and with automatically interchangeable tools (e.g., see U.S. Pat. No. 4,512,068, above). Tuned damped absorbers, often referred simply as "dampers", comprise a body of art for introducing structural damping where desired. But dampers are typically applied in structural locations not subject to changes which would effect frequency response. Thus, dampers have not, traditionally, been applied to the workpiece fixture side of a machining center, for example, because of the potential changes in mass of the different workpieces which are machined.
With regard to machine tool subassemblies, a prior art damper has been applied to the wheelhead of a grinding machine; such damper is found in U.S. Pat. No. 3, 522,864, of R. C. Richter, issued Aug. 4, 1970, entitled Tuned Vibration Damper Assembly for Machine Tools. In this Patent, a wheelhead is rockable about a pivot point, and a tuned damper is mounted to an angled face of the wheelhead. The damper comprises a damping mass, a resilient member between the wheelhead and damper mass, and a bolt and spring combination for securing the mass to the wheelhead face in a manner preloading the resilient member. The resilient member acts in shear along the angled face, providing components of shear damping in the X and Y direction, which counteract moments of vibration about the pivot point.
With regard to the "cutter side" of a machine, i.e., as opposed to the workpiece fixture side of the machine, a rotary damper has been applied to the cutter arbor of a horizontal milling machine. This damper is depicted in U.S. Pat. No. 2,714, 823, of A. H. Dahl et al., issued Aug. 9, 1955, entitled Vibration Damper.
Damping has also been applied to a boring bar support of a turning machine, as shown in U.S. Pat. No. 5,033,340, of L. T. Siefring, issued Jul. 23, 1991, entitled Apparatus and Method for Tool Vibration Damping.
It is also known to place a damper inside a boring bar which supports a cutter. U.S. Pat. No. 3,447,402, of J. C. Ray, issued Oct. 25, 1967, entitled Damped Tuned Boring Bar, shows such a structure.
With regard to the "workpiece side" of a machine tool, an example of a vibration damping apparatus applied directly against a stationary workpiece is shown in U.S. Pat. No. 5,494,269, of P. E. McCalmont, issued Feb. 27, 1996, entitled Vibration Damper. In this structure, a damping unit is mounted to a machine table and is manually actuated to load a damping head against an otherwise unsupported cantilevered workpiece portion; the damping head is retracted when the workpiece is to be removed from the machine.
Another a workpiece damper is depicted in U.S. Pat. No. 4,438,599, of J. T. Kamman et al., issued Mar. 27, 1984, entitled Vibration Damper for Machine-Carried Workpiece. In this patent, a shoe held in a shoe holder by viscoelastic pads is applied directly against a slender rotating workpiece, to attenuate workpiece vibrations.
The present invention is applicable to the workpiece side of a machine tool, and is particularly pertinent to those situations where the workpiece mass comprises a small percentage of total mass of fixture and workpiece, and where the change in total mass as the workpiece is machined, is also small. The invention obviates many of the difficulties inherent in the prior art devices, by incorporating a tuned damper into a tombstone fixture for supporting workpieces.


A redundant control system for controlling an electromechanical system is provided. The control system includes a first processor, a second processor, an input-output node, a first communication channel, a second communication channel, and a signal selector. The first and second processors have a control algorithm and state variables resident thereon. The first and second processors each generate an output signal based on the control algorithm, the state variables, and an input signal from the electromechanical system. The first communication channel communicates the input signal and the output signal between the first processor and the input-output node, while the second communication channel communicates the input signal and the output signal between the second processor and the input-output node. The signal selector communicates either the output signal from the first processor or the output signal from the second processor to the electromechanical system.

The present disclosure relates to control systems. More particularly, the present disclosure relates to redundant control systems and methods.
Complex electromechanical systems such as, but not limited to power generators and industrial co-generators, require a control systems that operate the various components of the electromechanical system. Such control systems include a processor that guides the actions of the electromechanical system. In the event of a failure of the processor, the entire electromechanical system fails.
The reliability of a control system is directly related to the level of redundancy in the components in the control system. Thus, it has been proposed to use two or more, redundant processors with such electromechanical systems in order to improve the reliability of the control system.
Prior art control systems having two processors have typically been implemented using a primary/secondary hierarchy. In this hierarchy, the secondary processor serves as a backup processor to the primary processor. When a failure of the primary processor occurs, the control system must first detect the failure, then must switchover control of the electromechanical system to the secondary processor. The time required for failure detection can result in control interruptions. In addition, the switchover often requires re-routing of input and/or output packets from the primary processor to the secondary processor, which can also result in control interruptions.
Thus, dual redundant control systems using primary/secondary hierarchy unfortunately result in control interruptions, which can negatively effect the operation of high-speed control loops.
Accordingly, it has been determined that there is a need for redundant control systems that overcome, mitigate and resolve one or more of the above and other deleterious effects of prior art dual redundant control systems.


A weighted skipping exercise device for cardio-aerobic exercise. A leg ring is attached to a cone element containing adjustable weights by an elongated cord. The elongated cord having a first loop end positioned within a channel around a the outer circumference of the leg ring. A second cord end connected to the cone element by an attaching means permitting free rotation of the cone element. The cone element comprising a top cone attached to the second cord end and a bottom cup having a circular slot for containment of the adjustable weights. The top cone and bottom cup threaded together by a friction ring comprise the cone element. The cone element and adjustable weights attached by the elongated cord revolve in a circular path around the user by movement of the leg ring positioned around a user's first leg and continuous revolutions maintained byjumping or skipping over the circular path of the device with a second leg of the user.

Skipping toys using a leg ring and object attached by an elongated cord have been known for many years for use primarily as amusement toys. In operation, the leg ring is placed around a user's leg and by continuous movement of said leg the attached object and elongated cord revolve in a circular path requiring the user to skip or jump over the elongated cord with the opposite leg to maintain continuous revolutions.
The prior art discloses variations of the revolving object to increase the amusement of these toys. One example is disclosed in U.S. Pat. No. 5,603,651 (Shure et al.) in which a bubble producing mechanism is enclosed in the revolving object. Another example is disclosed in U.S. Pat. No. 6,113,452 (McGowan et al.) in which the revolving object contains a marker for marking the surface as the object travels.
Another example is disclosed in U.S. Pat. No. 6,695,671 B2 (Kessler) which the revolving object is a wheel containing small lamps and a generator which light upon rotation.
The present invention has for its primary objective to provide a cardiovascular aerobic device utilizing an improved leg ring, an elongated cord and a cone element adapted for quick and easy adjustment of weights contained therein. Additional uses include leg shaping and conditioning, sports training and stress reduction.


Described herein is a polyherbal composition effective in skin care, including singularly or in certain combinations 0.01% to 15% of Ziziphus extract, 0.01% to 10% of Prunus extract, suitable delivery system, and a suitable carrier.

Skin is one of the largest organs of the human body. While the skin carries out many functions, the most important ones include protection from the environment, helping to control body temperature as well as fluid and electrolyte balance. Skin also contains nerve receptors that allow you to feel sensations such as touch, pain, and pressure.
Although skin has many layers, it can be generally divided into three main parts namely, the outer part (epidermis) which contains skin cells, pigment, and proteins; the middle part (dermis) which contains blood vessels, nerves, hair follicles, and oil glands besides providing nutrients to the epidermis; and the inner layer under the dermis (the subcutaneous layer) which contains sweat glands, some hair follicles, blood vessels, and fat. Each layer also contains connective tissue with collagen fibers to give support and elastin fibers to provide flexibility and strength.
Skin changes are amongst the most visible signs of skin aging. Evidence of increased aging is manifest in the form of wrinkles, sagging of skin, increased pigmentation and development of age spots.
While skin changes are related to environmental factors, genetic makeup, nutrition, and other factors, the greatest single factor, though, is sun exposure. With aging, the epidermis begins to become thinner, even though the number of cell layers remains unchanged. Also, while the number of pigment-containing cells (melanocytes) decreases, the remaining melanocytes tend to increase in size. Aging skin thus appears thinner, more pale, and clear (translucent). Large pigmented spots (called age spots, liver spots, or lentigos) may begin to appear in sun-exposed areas.
Sebaceous glands produce less oil as you age, making it harder to keep the skin moist, resulting in dryness and itchiness. The sweat glands produce less sweat, making it harder to keep cool, and one is at an increased risk of becoming overheated or developing heat stroke. Growths such as skin tags, warts, and other blemishes are more common in older people.
Changes in the connective tissue reduce the skin's strength and elasticity. This condition is referred to as elastosis and is especially pronounced in sun-exposed areas such as the face (solar elastosis). Elastosis produces a leathery, wrinkled, weather-beaten appearance common to labourers, farmers, sailors, and others who spend a large amount of time outdoors.
A skin wrinkle is a fold, ridge or crease in the skin, which typically appears as a result of aging processes such as glycation or, is caused by habitual facial expressions, aging, sun damage, smoking, poor hydration, and various other factors. Changes in the collagen-elastin matrix brought about by aging as well as the action of Matrix Metalloproteinases (MMP) further aggravates this condition, resulting in the development of fine lines and wrinkles (crow's feet) and as aging progresses, more prominent lines at the naso-labial regions of the face.
A number of ingredients and techniques have been tried to address the problem of skin aging. Well known among the various options is the use of Tretinoin, Epidermal Growth factors, Glycosaminoglycans, Dermal fillers, Botox, Collagen injections, etc. Each of these solutions to aging and wrinkles come with their own advantages as well as disadvantages.
Various plants and herbs have also been used in Ayurveda as well as Chinese and Oriental medicine to counter aging. Ziziphus mauritiana (Ziziphus zizyphus) commonly called jujube (sometimes jujuba), red date, Chinese date, Korean date, or Indian date is a species of Ziziphus in the buckthorn family Rhamnaceae, used primarily as a fruiting shade tree. While the fruit is primarily used for edible purposes, there exists certain literature exists which speaks of the anti-aging benefits of the fruit.
Prunus puddum (Prunus cerasoides, Wild Himalayan cherry) is a deciduous cherry tree found in East Asia. It is of the family Rosaceae and the genus Prunus. It grows in the forests from 1200 to 2400 meters above sea level. Heartwood of Prunus cerasoides is moderately hard, strong, aromatic, astringent, bitter, acrid, refrigerant, antipyretic and tonic. It is useful in vitiated conditions of pitta, burning sensations, sprains, wounds, ulcers, leprosy and skin discolorations. It has action similar to olive oil and is used in emollient preparations including nourishing creams, skin creams and cold creams.
Various delivery formats have been used to enhance the efficacy and/or penetration of active ingredients into the skin; some of the latest being liposomes and nanoparticles.

Shiromani Gurudwara Prabandhak Committee's Guru Nanak Khalsa College


Memory system operations are extended for a data processor by an application programming interface API, including a set of operations and parameters for the operations, which provides for data compression and decompression during or in conjunction with processes for moving data between memory elements of the memory system. The set of operations can be configured to use the parameters and perform the operations of the API. The API can support moves between memory having a first access latency, such as memory integrated on the same chip as a processor core, and memory having a second access latency that is longer than the first access latency, such as memory on a different integrated circuit than the processor core.

1. Field of the Invention
The present invention relates to computer system operation, including data transfer operations among the elements of a memory system that include data compression and decompression.
2. Description of Related Art
In some computer systems, including multicore processors systems and graphical processor systems, memory is organized hierarchically. The memory hierarchy can include a relatively small first level (L1) cache memory and a larger second level (L2) cache memory on the same integrated circuit as the processor core circuitry, along with off-chip, large scale memory implemented often using dynamic random access memory. In some configurations, a third level (L3) cache can be included on-chip. Other memory can be used for sharing data among processor cores, such as shared cache memory and message-passing memory. Additional memory in the hierarchy can include persistent stores, such as flash memory, magnetic disk drive memory, network-attached storage and so on. Given the variety of memory technologies, the organization of memory systems is very diverse.
Also, there are many varieties of computer system architectures, each of which can include different memory system configurations. My co-pending U.S. patent application Ser. No. 12/891,312, entitled ENHANCED MULTI-PROCESSOR WAVEFORM DATA EXCHANGE USING COMPRESSION AND DECOMPRESSION, filed 27 Sep. 2010 (US 2011/0078222), which is incorporated by reference as if fully set forth herein, describes several computer system architectures, and demonstrates the variety architectures and memory configurations being commonly deployed.
As processor performance has improved, processors are executing programs over larger and larger data sets. Also, one processor or group of processors may concurrently execute many programs, each of which requires access to different sizes and types of data sets. For example, broad varieties of application programs acquire, collect, process, and display numerical data. Numerical data includes a variety of data types, such as integers, floating-point numbers, image data, video data, and graphics objects. Numerical data can be accumulated in large files, or acquired at high speeds, and movement of such data among elements of processor system memory hierarchies can cause bottlenecks in system performance.
Thus, the amount of memory available, in terms of the number of bytes, at each element of a memory system for a given computer system, and the bandwidth of the data channels among the elements of the memory system, can limit the efficiency and speed with which a given program can be executed. Given the variant computer systems architectures and variant memory system configurations, the control of data flow among the memory elements is often implemented in a platform-specific manner. This platform-specific memory management interferes with users' ability to individually manage data flow to improve the efficiency of the utilization of memory resources in a given computer system.
It is desirable to provide technologies that can be employed to improve efficiency of memory system operations in computer systems.

Processing system and method including data compression API


The invention relates to a mobile communications device comprising a housing, a transceiver in the housing, a keypad connected to the housing, and a display connected to the housing, wherein the housing comprises a first section movably connected to a second section of the housing by a multi-axis hinge, wherein a first axis of rotation of the hinge is provided at the first section of the housing and a second offset axis of rotation of the hinge is provided at the second section of the housing, and wherein the hinge comprises means for synchronizing rotation of the first and second sections relative to the hinge through a path of about 360 degrees. The invention further relates to a hinge for use therein.

U.S. Patent Publication No. US 2002/0154475 A1 discloses a folding electronic device. The device has a first part with a keyboard and a second part with a display. The second part is connected to the first part by a two-joint mechanical hinge. The second part can be moved between a first position against a first side of the first part and a second position against an opposite second side of the first part.
Fold mobile phones, also known as a flip phone or a clamshell phone, are becoming more and more popular in today's mobile telephone market, especially in Asia. In normal fold mobile phones, the phones have a lid with a display which pivots about 160-180 degrees relative to the portion of the telephone having the keypad. The fold phone has two positions of the lid; either a closed position or an open position.
There is a desire for a new type of reconfigurable mobile telephone which can be configured similar to a conventional flip phone, and which also can be reconfigured with the lid pivoted more than 180 degrees, such as 360 degrees. However, for such a multi-open position fold mobile telephone, there is a desire to provide a robust and compact design which can provide a smooth opening and closing motion for the user. This type of motion will prevent the user from erroneously perceiving the mobile telephone as having a flimsy construction (which might be perceived from a flip phone which opens and closes too easily or with a hinge that does not move in a consistent repetitive fashion).
The Japanese patent document JP2003-309756 discloses a foldable mobile telephone, wherein a display portion is pivotable 180 degrees around a first axis relative a keyboard portion. The display portion is moreover pivotable 90 degrees around a second axis perpendicular to the first axis. A user of the mobile telephone may hence more freely turn the display portion to a desired direction. However, the structure of the hinge according to JP 2003-309756 does not allow a 360 degree folding of the two portions forming the mobile telephone.
US 2003/0172495 A1 discloses a flip phone having a hinge mechanism with an auto-lock function. The flip phone includes a main body and a flipper connected by means of the hinge. The hinge is arranged to rotatably connect the flipper to the main body so as to provide an opened position or a closed position for the flipper. In the open position, the flipper is positioned at an angle approximately 160 degrees relative the main body.

Mobile communications device with synchronising hinge


A method of using tester data packet signals and control instructions for testing multiple data packet signal transceiver devices under test (DUTs). During mutually alternating time intervals, selected ones of which are substantially contemporaneous, multiple tester data packet signals and DUT control instructions are used for concurrent testing of multiple DUTs.

The present invention relates to testing data packet signal transceivers, and in particular, to achieving faster test times by using interleaved device setup and testing.
Many of today's electronic devices use wireless technologies for both connectivity and communications purposes. Because wireless devices transmit and receive electromagnetic energy, and because two or more wireless devices have the potential of interfering with the operations of one another by virtue of their signal frequencies and power spectral densities, these devices and their wireless technologies must adhere to various wireless technology standard specifications.
When designing such wireless devices, engineers take extra care to ensure that such devices will meet or exceed each of their included wireless technology prescribed standard-based specifications. Furthermore, when these devices are later being manufactured in quantity, they are tested to ensure that manufacturing defects will not cause improper operation, including their adherence to the included wireless technology standard-based specifications.
For testing these devices following their manufacture and assembly, current wireless device test systems (also referred to as "testers") employ a subsystem for analyzing signals received from each device. Such subsystems typically include at least a vector signal generator (VSG) for providing the source signals to be transmitted to the device under test, and a vector signal analyzer (VSA) for analyzing signals produced by the device under test. The production of test signals by the VSG and signal analysis performed by the VSA are generally programmable so as to allow each to be used for testing a variety of devices for adherence to a variety of wireless technology standards with differing frequency ranges, bandwidths and signal modulation characteristics.
As will be readily appreciated, testing of a data packet signal transceiver, also referred to as a device under test (DUT), requires a finite amount of time. Depending upon the wireless technology or standard (and sometimes multiples of which) for which the DUT is to be tested, it will take more or less test time for the DUT to be fully tested to confirm its proper functioning and operation. Times required for these tests have been reduced at times by applying various testing techniques, though further changes in techniques have tended to be insignificant, thereby bringing diminishing returns. As a result, testing techniques have been focused on testing multiple DUTs concurrently so that even though the actual test time per device may not be reduced appreciably, the number of DUTs tested in that time interval increases, thereby having the net effect of reducing overall per-DUT test time, and thereby reducing testing costs for each DUT.
However, when multiple DUTs are to be tested concurrently, using a test system, also referred to as a tester, having a single test signal source (e.g., a single VSG) and a single test signal analyzer (e.g., a single VSA), it is generally not possible to perform a transmit signal test simultaneously for all DUTs. This is due to the fact that the test signal analyzer can only receive, capture and analyze a transmit signal from one DUT at a time. For receive signal testing, where the single test signal source provides a single test signal, it is possible to replicate the test signal using power dividers, and thereby provide simultaneous test signals to multiple DUTs. However, in cases where each DUT has multiple receivers (e.g., multiple-input, multiple-output, also referred to as MIMO), each DUT will still require testing individually, since sourcing the same signal to all DUT receive ports will not allow detection of a bad individual receiver among the DUT receiver circuitry. Thus, each DUT must be controlled between each test sequence. Alternatively, multiple test signal sources can be used to generate multi-stream test signals, but such test signal sources tends to be prohibitively expensive for replicating on the scale needed for manufacturing tests of many DUTs.
In particular, two tasks necessary to perform during DUT testing are those of controlling (e.g., preparing or setting up) the DUT for its upcoming test, and allowing time for the DUT transmitter circuitry to settle to its steady state operation and thereby provide consistent transmit signal power. Both of these tasks must generally be performed at the beginning of a transmit signal test, and can be longer (often significantly) than the duration of the test data packet exchanges between the tester and DUT.
Accordingly, it would be desirable to have a technique for testing data packet signal transceivers in which that time otherwise lost while awaiting initial setup of the DUT for the upcoming test sequence and power settling of its transmitted data packet signal can instead be used for performing useful tasks that are part of, or otherwise associated with, the test to be performed. Additionally, if such testing method could be applied to multiple DUTs for simultaneous testing, further time savings could be achieved.

This patent is subject to a terminal disclaimer.

Method for testing data packet signal transceivers using interleaved device setup and testing


An optical semiconductor includes a photo diode integrated with a transistor built on first and second epitaxial layers grown on a substrate, the first epitaxial layer is grown on the substrate from intrinsic material. The second epitaxial layer is grown doped on the first epitaxial layer. A separating area divides the optical semiconductor into first and second isolated islands. The separating area is made up of a lower separating area, a middle separating area and an upper separating area united to form a single separating area. The lower separating area is diffused at least upward from an interface between the substrate and the first epitaxial area. The middle separating area is diffused both downward and upward from an interface between the first and second epitaxial layers. The upper separating area is diffused downward from the surface of the second epitaxial layer. The photo diode is formed in the first island area, and the transistor is formed in the second island area. A counterdoped region in the surface of the substrate, at least below the first island, expands the depth of the depletion region of the photo diode. The separating area enters the substrate to a depth corresponding to the depth of the counterdoped region.

This invention relates to integrated circuits and, more specifically, to an optical semiconductor device having, integrally formed therein, a photo diode and a bipolar transistor.
Compared to a hybrid IC combined with a separately produced light receiving element and external circuit elements, a monolithic optical semiconductor device, integrally combining a light receiving element and a peripheral circuit, can be produced at a lower cost and is relatively immune to noise from external electromagnetic fields.
Referring to FIG. 9, a conventional optical semiconductor device is disclosed in, for example, Japanese Laid-open Patent Publication No. 1-205564. A P-type semiconductor substrate 1, has epitaxially grown thereon a P-type epitaxial layer 2. An N-type epitaxial layer 3 is epitaxially grown on epitaxial layer 2. A plurality of P.sup.+ -type separating areas 4 separate epitaxial area 3, and contiguous upper portions of epitaxial layer 2 into isolated islands. A first island is used to form a photo diode 9. A second island is used to form an NPN transistor 10.
Photo diode 9 includes an N.sup.+ -type diffusion area in its upper surface. An N.sup.+ -type buried layer 6 spans the interface between epitaxial layers 2 and 3 in the island forming transistor 10. The portion of epitaxial layer 3 in transistor 10 functions as the collector thereof. A P-type base area 7 is disposed in an upper surface of transistor 10. An N.sup.+ -type N.sup.+ -type emitter area is disposed in an upper surface of base area 7. An N.sup.+ -type type collector contact area 12 is disposed in the upper surface of transistor 10 outside base area 7.
Photo diode 9 is biased to form a PN junction between P-type epitaxial layer 2 and N-type epitaxial layer 3. N.sup.+ -type diffusion area 5 serves as a cathode of photo diode 9. Separating area 4 serves as an anode of photo diode 9.
An accelerated electric field is formed in NPN transistor 10 by an auto-doped layer 11 in epitaxial layer 2 which became autodoped by diffusion of P-type carriers from substrate 1 during epitaxial growth and heat treatment Autodoped layer 11 retards the movement of carriers originating below the depletion region.
To obtain a high speed response of photo diode 9, the depletion region is widened to restrain the movement of carriers occurring outside the depletion region. In the structure in FIG. 9, automatic doping layer 11 overlaps P-type epitaxial layer 2. This overlap results in an increased concentration of impurities and an enlargement of the depletion region.
Epitaxial growth requires processing in a closed vessel into which gasses are fed to grow the desired layer, and to introduce the desired amount of impurities. During growth of P-type epitaxial layer 2, the closed vessel becomes contaminated with the P-type impurities. If an attempt were made to grow N-type epitaxial layer 3 in the same closed vessel used to grow P-type epitaxial layer 2, the P-type contaminants in the vessel would enter epitaxial layer 3 in such amounts that it would be difficult or impossible to attain the desired properties in epitaxial layer 3.
As a consequence of the contamination of the vessel by P-type impurities during epitaxial growth of epitaxial layer 2, the device must be removed physically from the vessel after epitaxial layer 2 is formed, and placed in a clean vessel for growth of N-type epitaxial layer 3. This requirement for removing and reinstalling the workpiece during processing interferes with production. Thus, the same epitaxial growing device cannot be used to produce the prior-art device of FIG. 9.


A system for determining whether a velocity event is fake or real is provided. The system accesses a data store of velocity events, each of which specifies a pair of addresses that share the velocity event. For each address of the velocity events, the system sets a score for that address based on the number of addresses that share a velocity event with that address. When the score for that address satisfies an originating address criterion, the system designates that address as an originating address. The system may determine that a velocity event is real when both addresses of the velocity event are originating addresses.

Cyber-attacks cost companies and individuals billions of dollars. A report in 2015 stated that cyber-attacks cost companies over $400 billion annually. In addition to the financial costs, cyber-attacks may result in the destruction or loss of valuable information. For example, a ransomware attack may encrypt all the data on a personal computer, including the only copy of financial documents, family photographs, electronic mail messages, and so on. If the ransom is not paid, then the data may remain encrypted forever. Even if the ransom is paid, the attacker might not provide the key to decrypt the data. Because of the high costs of cyber-attacks, companies and individuals expend considerable resources in developing and purchasing security systems as defenses to cyber-attacks. These security systems include firewall systems, antivirus systems, authentication systems, intrusion prevention systems, access control systems, and so on.
Some defenses to a cyber-attack may rely on detecting the occurrence of a "velocity event." A velocity event, also referred to as a "velocity incident," occurs when a resource is accessed from two different locations within a period that is too short for a person to have reasonably traveled between the locations. FIG. 1 illustrates an example of a velocity event. A computer system 110 (i.e., a resource) may receive a logon request 120 for a user at 1:00 from a first Internet Protocol ("IP") address and receive another logon request 130 for the user at 2:00 from a second IP address. (An IP address that is provided to the computer system is considered to be a source IP address since it is the IP address of the computer from which the logon address was received.) An IP/location table 140 maps IP addresses to a corresponding physical address. In this example, the IP/location table maps the first address to New York City and the second address to Tel Aviv. Since the distance between New York City and Tel Aviv is over 5000 miles, it would not be possible for a person to travel from New York City to Tel Aviv within an hour. As such, the logons could not have been attempted by the same person who traveled between the locations. At least one of the logon requests may be an attempted cyber-attack by a hacker or some other unauthorized user. When such a velocity event is detected, countermeasures can be taken. The countermeasures may include locking the account of the user, requiring additional authentication (e.g., a multi-factor authentication), sending an email to alert the user, and so on.
Some velocity events may, however, be false positives in the sense that even though the IP addresses are associated with different locations, the user was not at one of the locations. Such a velocity event may be considered a fake velocity event, which is not problematic, as opposed to a real velocity event, which is problematic. A velocity event may be fake for various reasons. For example, the mappings of IP addresses to locations may not be accurate. As another example, a logon request that originates from a user's computer with one IP address may be directed through a server with a different IP address. The computer system that receives the logon request only knows that the logon request was sent from the IP address of the server. The IP address of the user's computer and the server are referred to the "originating" IP address and the "substitute" IP address, respectively. A substitute IP address may be used, for example, when the user attempts to logon to the computer system via a virtual private network ("VPN"). Thus, if a user in New York City first submits a logon request via their smartphone at 1:00 and then, while still in New York City, submits a logon request via a computer that is connected to a server in Tel Aviv at 2:00, a velocity event would be detected. The velocity event, however, would be fake.
If countermeasures were taken for every fake velocity event, considerable computer resources would be used unnecessarily. Thus, those computer resources would not be available to detect and prevent cyber-attacks. In addition, the users may consider the countermeasures (e.g., locking an account) as onerous and as placing an undue burden on the users.


Chromatographic separations are often characterized by multiple detectors through which the sample flows serially. As the sample flows between detectors, it becomes progressively diluted due to mixing and diffusion. This phenomenon is traditionally called interdetector “band broadening” and often results in significant distortion of the sample's derived physical properties such as molar mass. A method to characterize the broadening present in a chromatographic system, and an algorithm whereby the narrow peaks of the upstream detector are numerically broadened so they can be compared to the broadened peaks of the downstream detector, is described. Although the technique results in some loss of resolution, its stability and generality allow it a broad range of application. Examples are presented for data collected by dRI, MALS, UV, and viscometric detectors.

The analysis of macromolecular species in solution by liquid chromatographic techniques is usually achieved by preparing a sample in an appropriate solvent and then injecting an aliquot thereof into a chromatograph. The chromatograph includes fractionation devices of various types that separate the sample as it passes through them. Once separated by such means, generally based on size, mass, or column affinity, the samples are subjected to analysis by means of light scattering, refractive index, UV, viscometric response, etc. For example, in order to determine the mass and size distributions of a particular sample whose separation is performed by size exclusion columns, the chromatograph would measure the sample sequentially by multiangle light scattering, MALS followed by a differential refractometer, dRI. The dRI determines the concentration while the MALS unit measures the excess Rayleigh ratio as a function of angle of each eluting fraction. For molecules very much smaller than the wavelength of the incident light, light scattering measurements at a single angle may often be sufficient.
As each fraction passes through a detection device, it produces a signal often referred to as a "band" or "peak." Because of dispersion and mixing effects, these bands are broadened somewhat each time the sample passes through a different device. Consider a sample comprised of a low concentration aliquot of a monodisperse protein. In this event, the Rayleigh excess ratio is directly proportional to the molar mass and the concentration. The light scattering signal and the concentration signal should be of identical shape and would overlay perfectly were the two responses normalized to have the same areas. However, as the sample passes from the MALS detector and enters the dRI detector, it passes through intermediate regions and connections that contribute to the dispersion and mixing of the sample. Many sources of band broadening and some of their remedies are discussed in detail by Yau, et al. in their book "Modem size exclusion liquid chromatography" published by John Wiley & Sons in 1979. In the above example, the dRI signal will always appear somewhat broadened with respect to the MALS signals.
The effect of broadening is shown clearly in FIG. 1 which shows a chromatogram of a sample of bovine serum albumen, BSA, in an aqueous buffer along with the computed molar mass, uncorrected for the effects of broadening. The uncorrected molar mass is shown in trace 1. It is presented divided by the molar mass of the monomer, Mw0, so that the vertical axis for the monomer reads 1, the dimer reads 2, etc. Trace 2 corresponds to the 90° light scattering signal as a function of time. Trace 3 corresponds to the dRI signal. The aggregation states have been fractionated so that the rightmost peak region, from 16 minutes to 18 minutes, is data from the pure monomer, from 14 minutes to 16 minutes is from the dimer, etc. In each peak, broadening causes the concentration at the center of the peak to be suppressed and that in the "wings" to be enhanced. Combining this broadened dRI signal with the MALS signals to determine molar mass at each elution time causes the molar mass determined near the peak's center to be systematically overestimated, while that in the wings to be underestimated. The situation reverses when the concentration detector is upstream of the MALS detector. This gives rise to the non-constant molar mass data within each peak region. If there were no band broadening, the data would consist of a series of plateaus at 1 for the monomer, 2 for the dimer, etc. As the fractionated sample becomes more polydisperse, the effects of band broadening become less apparent (but are still present). For a well fractionated sample comprised of discrete aggregate states, the problem is obvious. In FIG. 1, the monomer peak is well resolved so the broadening problem is clearest. The aggregates are progressively less well resolved so they show the problem to a lesser extent.
In order to compensate for these distortions, a variety of methods have been employed. Most are based upon the work of L. H. Tung presented in his 1969 paper published in the Journal of Applied Polymer Science, volume 13, p 775 et seq. The afore-referenced book by Yau et al. discusses some of the means to correct band broadening. Throughout the chromatography literature, many papers address means to perform these corrections, i.e. to restore the broadened band to the shape it would have had were no broadening sources present. Most of the techniques are numerically unstable and can result in physically unreasonable results, such as negative concentrations, or negative scattered intensities, and therefore are rarely used. The characterization of proteins by MALS measurements represents an area of particular importance, yet even here, band-broadening corrections are rarely seen because of the difficulties associated with their implementation.
Band broadening effects occur in a variety of multi-detector implementations of liquid chromatography. For example, if a sample is to be measured by an on-line viscometer so that its intrinsic viscosity may be determined, then a dRI will also be needed. As the sample passes from the dRI to the viscometer, it will experience band broadening resulting in a spreading of the specific viscosity curve with respect to the concentration curve derived from the dRI measurement. Again, the computational difficulties, associated with restoring the broadened signal to conform to what it would have been without broadening, often result in questionable results, especially if the samples are indeed monodisperse such as unaggregated proteins.
It is the purpose of the present invention to provide an analytical method by which band-broadening effects may be corrected in software with both ease and precision. Another objective of the invention is to provide a new approach to such corrections whose departure from the conventional approach is sharply distinguished therefrom. The present invention is expected to be of greatest utility for the analysis of separations of protein samples. A consequence of this application will be the more precise characterization of protein conjugates as well as aggregate states. A further application of this invention is its ability to improve the determination of intrinsic viscosity measurements by correcting the band broadening effects associated with the sample passage between a concentration detector and a viscometer. An important application of the invention will be its application to the rapid determination of the 2nd virial coefficient of an unfractionated sample as discussed, for example, in U.S. Pat. No. 6,411,383 and the application Ser. No. 10/205,637 filed 24 Jul. 2002, now in process of issuance, by Trainoff and Wyatt. The successful implementation of that method depends critically upon the ability to determine accurately the square of the concentration at each elution volume. This requires an accurate measurement of the concentration at each such elution volume. The latter determinations are made generally on unfractionated samples whose detector responses are a single peak whose mass composition is the same at each interval collected. This single peak is broadened as it proceeds through the series of detectors leading to systematic errors in the derived results, unless the effect of broadening is corrected.

Method for correcting the effects of interdetector band broadening


A method is provided, comprising the steps of reacting a biologically active first substance immobilized on a carrier with a second substance capable of specifically binding the first substance, and detecting a non-bound part of the second substance or a bound part of the second substance indirectly bound to the carrier through binding between the first and second substances so that the first substance or the second substance in a sample is analyzed, wherein the carrier carries a compound having 2 to 100 carbodiimide groups, and the first substance is immobilized on the carrier through the carbodiimide groups so that the active substance such as protein and nucleic acid is bound to the carrier conveniently, efficiently, and tightly.

Biologically active substances such as nucleic acid, antibody, and antigen existing in a specimen are detected and identified in certain fields such as clinical examination, food inspection, and medicolegal inspection. Several methods are used for such detection and identification depending on objective substances, including, for example, nucleic acid probe techniques and enzyme immunoassay methods.
The field, in which nucleic acid is detected, includes, for example, identification of microbial species such as pathogenic microorganisms, and DNA tests in legal medicine. Usually, in the detection of nucleic acid, a nucleic acid having a sequence complementary to a target nucleic acid is used, which is directly labeled with an enzyme or the like, or indirectly labeled through a hapten or the like. The labeled nucleic acid is hybridized with the target nucleic acid. The presence and the amount of the target nucleic acid can be confirmed by detecting a hybridized labeled portion after removing a non-hybridized part of the labeled nucleic acid or after inactivating a non-hybridized labeled portion.
The field, in which antigen, antibody or the like is detected, includes, for example, identification of microbial species such as pathogenic microorganisms in the same manner as described for the nucleic acid, as well as various clinical examinations. A competitive enzyme immunoassay method, which is an embodiment of the enzyme immunoassay method used to detect antigen and antibody, is performed as follows. An antibody or an antigen is immobilized on a surface of a solid phase such as polystyrene bead, microtiter plate, and tube. A certain amount of a specimen solution is applied to the solid phase surface, and then an antigen-enzyme complex or an antibody-enzyme complex is added. When the antibody is immobilized on the solid phase surface, the antigen in the specimen and the antigen-enzyme complex compete in a binding reaction to the antibody immobilized on the solid phase surface. When the antigen is immobilized on the solid phase surface, the antigen in the specimen and the antigen immobilized on the solid phase surface compete in a binding reaction to the antibody-enzyme complex.
After passage of a certain period of time, when the antibody is immobilized, the antigen and the antigen-enzyme complex, which do not bind to the immobilized antibody, are washed and removed. When the antigen is immobilized, unreacted parts of the antigen in the specimen and the antibody-enzyme complex, and a bound product between the antigen i n the specimen and the antibody-enzyme complex are washed and removed. The washing in this procedure is usually performed by repeating a washing operation several times to ten times. The washing operation comprises filling a solid phase section with a washing solution, discarding the washing solution, filling the solid phase section with a fresh washing solution again, and discarding the washing solution again. This operation is generally called "B/F separation" which is an essential operation in the inspection based on the principle of the enzyme immunoassay method.
In the final step, a coloring substrate solution for the enzyme used to label the antigen or the antibody is added to the solid phase section, and then a color is developed by the remaining enzyme. Generally, the enzyme used in this procedure is, for example, peroxidase, .beta.-galactosidase, and alkaline phosphatase. A substrate appropriate for each enzyme is used as the substrate for color development. If the antigen as the target exists in a large amount in the specimen solution, the amount of the remaining antigen-enzyme complex or the remaining antibody-enzyme complex is decreased, resulting in a weak intensity of color development. The intensity of color development is generally measured by using a calorimeter.
In a sandwich enzyme immunoassay method as another embodiment of the enzyme immunoassay method, an antibody is immobilized on a solid phase surface, and a specimen solution is applied to the solid phase surface. After passage of a certain period of time, a part of an antigen which does not bind to the antibody on the solid phase surface is washed and removed. After that, a certain amount of an antibody-enzyme complex is added. After passage of a certain period of time, a part of the antibody-enzyme complex which does not bind to the antigen on the solid phase surface is washed and removed, and then a coloring substrate is applied to the solid phase surface to develop a color. The concentration of the antigen in the specimen can be quantitatively determined by measuring the intensity of the color development.
It is extremely important to immobilize antibody, antigen, enzyme, nucleic acid, or the like on the solid phase surface such as tube, microtiter plate, membrane filter, and beads in the conventional methods such as the nucleic acid detection method, the competitive enzyme immunoassay method, and the sandwich enzyme immunoassay method described above. Accordingly, various methods for immobilizing biologically active substances have been published. For example, known methods for protein include:
(1) a method for chemically binding a protein to a base material by using a cross-linking agent or a condensation agent, such as a diazo method, a peptide method, an alkylation method, a base material-binding method by using a cross-linking agent, and a base material-binding method based on Ugi reaction (see "Immobilized Enzyme", ed. by Ichiro Chibata, Kodansha Scientific (1986), pp. 9-41); PA1 (2) a method for immobilization to a base material by using ionic bond (see "Immobilized Enzyme", pp. 41-43); and PA1 (3) a method for immobilization to a base material by using physical adsorption (see "Immobilized Enzyme", pp. 43-45). PA1 (1) a method for chemically binding nucleic acid which is provided with an introduced modified group, as exemplified by immobilization through a disulfide bond between nucleic acid having a thiol group at its 5'-terminal and a bead-shaped base material involving a thiol group (see P. J. R. Day, P. S. Flora, J. E. Fox, M. R. Walker, Biochm. J., 278, 735-740 (1991)) (other methods belonging to this category are described in, for example, Soren R. R., Mette R. L., Svend E. R., Anal. Biochm., 198, 138-142 (1991); Jonathan N. K., Joseph L. W., Joseph P. D., Rachel E. M., Mary C., Eugene L. B., Nucleic Acids Res., 15, 2891-2909 (1987); Allan J. M., Jeffrey R. B., Terence W. P., Biochem. J., 191, 855-858 (1980); J. A. Running, M. S. Urdea, BioTechniques, 8, 276-279 (1990)); and PA1 (2) a method for immobilizing nucleic acid by using physical adsorption such as immobilization by adsorption onto a nitrocellulose or nylon membrane by means of UV irradiation or heat treatment (J. Sambrok, E. F. Fritsch and T. Maniatis, Molecular Cloning, Cold Spring Harbor Laboratory Press, Second Edition, pages 2.109-2.113 and pages 9.34-9.46), and immobilization by physical adsorption onto a microplate (G. C. N. Parry and A. D. B. Malcolm, Biochem. Soc. Trans., 17, 230-231 (1989). PA1 reacting a biologically active first substance immobilized on a carrier with a second substance capable of specifically binding the first substance; and PA1 detecting a non-bound part of the second substance or a bound part of the second substance indirectly bound to the carrier through binding between the first and second substances so that the first substance or the second substance in a sample is analyzed; PA1 wherein the carrier comprises a compound having 2 to 100 carbodiimide groups, and the first substance is immobilized on the carrier through the carbodiimide groups.
Known methods for nucleic acid include, for example:
However, it has been pointed out that the conventional methods as described above have drawbacks. For example, the method based on chemical bond requires special reagents including, for example, toxic substances such as azide, isocyanate, and NaBH.sub.3 CN. Further, when immobilization is performed by using peptide bond, for example, it is necessary to introduce an amino group into any one of an active substance and a base material, and it is necessary to introduce a carboxyl group into the other. Moreover, it is necessary to provide a step of mutually treating both of the introduced functional groups with a condensation reagent to achieve immobilization. Accordingly, it is inevitable to suffer complicated operations.
In the case of the method based on chemical bond, for example, amino groups must be present in both of the base material and the active substance in order to use glutaraldehyde as a cross-linking agent. Accordingly, it is necessary to select the base material because the base material itself must have the functional group. As a result, it becomes difficult to select the base material suitable for immobilization. In addition, for example, the method base on a chemical reaction is difficult to be used for those having only functional groups with poor reactivity (for example, terminal phosphate group, and terminal hydroxyl group) such as natural DNA and DNA having no modified group. Thus the method based on chemical bond has a drawback that immobilization cannot be achieved when the active substance has no active functional group.
On the other hand, the physical adsorption has the following drawback. Namely, the amount of immobilization is affected by adsorption performance of the base material, and the adsorbed active substance is liable to desorb. When the active substance is a low-molecular weight compound (oligomer), it is scarcely adsorbed because it has weak interaction with the base material.
As described above, many problems remain in the immobilization which is important to detect active substances such as protein and nucleic acid.

Method for analyzing biologically active substances


Endocardial or intravascular cardiac pacemaker having a sealed housing, in which a battery and a pacemaker controller connected to the battery, as well as at least one stimulation pulse generator, are situated, the housing being oblong and having a length of less than 70 mm and a cross-sectional area of less than 100 mm2 and carrying at least two electrodes, each of which has an outwardly directed, electrically conductive surface and is implemented as a stimulation electrode and is at least sometimes electrically connected to the stimulation pulse generator via an electrical connection situated in the interior of the housing.

Implantable cardiac pacemakers in their basic known form have housings in which a battery is situated, which allows operation of the pacemaker over many years. The battery powers a pacemaker controller, which is typically connected to a detection stage for cardiac signals and to a stimulation pulse generator. Both the stimulation pulse generator and also the detection stage for cardiac signals are in turn connected to terminals for one or more electrode lines, which allow stimulation pulses generated by the stimulation pulse generator to be delivered to the muscle tissue of the heart (myocardium) or electrical potentials in the heart to be detected and processed.
The different modes of operation and variations of such cardiac pacemakers are known in principle and do not need to be explained further here. The mode of operation of a pacemaker is characterized by a standardized letter code. In the framework of this standardized nomenclature, a DDD pacemaker is a pacemaker which may deliver stimulation pulses to both the ventricle and also to the atrium, which may additionally detect electrical potentials both in the ventricle and also in the atrium, and which finally may be operated inter alia in a demand mode, in which stimulation pulses are only delivered to the ventricle or to the atrium when this is required, i.e., when an electrical potential accompanying a natural contraction of the atrium or ventricle is not detected within a ventricular or atrial escape interval. If a natural cardiac contraction is detected during the duration of the escape interval, the delivery of a corresponding stimulation pulse is suppressed (inhibited). A pacemaker which is capable of stimulating the atrium in the demand mode is referred to as an AAI pacemaker. The first letter describes the capability of the pacemaker of delivering stimulation pulses to the atrium, the second letter describes a capability of the pacemaker of detecting atrial cardiac actions, and the third letter describes the capability of the pacemaker of suppressing the delivery of an atrial stimulation pulse if a natural cardiac action is detected within a set interval, typically referred to as an escape interval. Correspondingly, a pacemaker which may stimulate the ventricle in the demand mode is referred to as a VVI cardiac pacemaker.
Known cardiac pacemakers are typically implanted beneath the clavicle of a patient. The connection to the heart is produced via flexible electrode lines, which end in the particular chamber of the heart (atrium or ventricle) and are provided with electrodes there. On the pacemaker side, the electrode lines are provided with standardized plugs, which engage in similarly standardized sockets of the cardiac pacemaker to produce the desired electrical connection. These sockets of the pacemaker are typically situated in a header of the pacemaker, manufactured from electrically insulating plastic, which is electrically connected via a bushing to the detection stage(s) and the stimulation pulse generator(s) in the interior of a sealed metal housing of the pacemaker. This metal housing additionally houses a battery for operating the pacemaker and control electronics. The stimulation pulse generators typically comprise capacitors in which the energy for a stimulation pulse is stored before delivery of a stimulation pulse. The capacitors are charged with the aid of a suitable charging stage, which acquires its energy from the battery of the pacemaker. Typically, a large part of this metal housing, if not even the largest part of the metal housing, is occupied by the battery of the pacemaker.
The present invention has the object of specifying a cardiac pacemaker which avoids many of the restrictions of the standard arrangement of a pacemaker presented here and thus opens up new fields of application for pacemaker treatment.

Cardiac pacemaker having a sealed oblong housing


A field recognition apparatus includes a first camera for imaging a forward field and a second camera for imaging a road surface. The second camera has a light axis tilted toward a downward direction for accurately tracking a characteristic point in consecutively captured images to calculate an optical flow and for accurately recognizing road structure information. In this manner, three dimensional information of obstacles in a field is accurately processed and detected.

In recent years, an apparatus having a camera is used for detecting a movement of the apparatus itself (i.e., an apparatus movement) or a movement of a moving body that carries the apparatus based on an image captured by the camera. The image captured by the camera is further analyzed for detecting three-dimensional information of an object in the image such as a position and a shape based on the apparatus movement and a movement of the object captured in the image (Refer to, for example, U.S. Pat. No. 6,535,114).
The apparatus movement and/or the movement of the object are, in general, detected by calculating an optical flow that vectorially represents a movement of an identical characteristic point in a sequence of successive images.
The optical flow reflects, by definition, the apparatus movement when the characteristic point is standing still, and reflects a combination of the apparatus movement and the movement of the characteristic point when the characteristic point is moving.
The camera on the moving body for detecting an obstacle is positioned to have a light axis aligned substantially in a horizontal direction for capturing a wide range of a field image in front of the moving body. The moving body may practically be an automotive vehicle or the like.
The apparatus movement, or the movement of the camera in reality, is typically detected by using the characteristic point on a surface of a road, because the characteristic point on the road is generally large in the captured image and is standing still when the characteristic point is carefully chosen. That is, the apparatus movement is detected based on the optical flow derived by tracing the characteristic point in the sequence of the successive images.
However, the camera positioned in the above-described manner with its light axis substantially aligned in a horizontal direction has a large pitch angle α about a value of 90 degrees to a vertically downward direction. Therefore, the optical flow derived by tracing the characteristic point of the road has a large detection error, thereby deteriorating the accuracy of the apparatus movement.
When the light axis of the camera has the pitch angle α as shown in FIG. 12, an imaging surface G that captures a far front field in an upper half and a near front field in a lower half generates an image that includes a movement of the characteristic point on the road projected thereon in a proportionally reduced manner to a distance from the camera. That is, the same amount of the movement of the characteristic point on the road is captured as a larger movement image in the lower half of the imaging surface G when the characteristic point is positioned closer to the camera on the moving body, or is captured as a smaller movement image in the upper half of the imaging surface G when the characteristic point is positioned far off from the camera.
Therefore, the optical flow based on the movement of the characteristic point in the captured image suffers from an error that is caused by a different behavior of the characteristic point depending on a position of the characteristic point in the imaging surface G. In general, the larger the pitch angle α is, or the farther the characteristic points is from a center of the imaging surface G, the greater the error is.
The following table shows a result of a simulation that simulates a movement of a vehicle in a lateral and front-rear directions (translational movements), and in a yaw direction (a rotational movement) based on the images of the road surface captured by the camera that is positioned in the specified pitch angle α. The table compares a true value of these movements with an average of the errors in the absolute value.
LateralFront-rearYawmovementmovementmovementTrueTrueTruePitch anglevalueErrorvalueErrorvalueErrorα(m/(m/(m/(m/(deg/(deg/[deg (rad)]frame)frame)frame)frame)frame)frame)5.7 (0.1) 0.20.00.20.10.31.211 (0.2)0.20.00.20.20.31.317 (0.3)0.20.00.20.20.31.723 (0.4)0.20.00.20.20.32.629 (0.5)0.20.00.20.20.34.3
The height of the camera from the road surface is 1.5 meter (the height of the camera corresponds to a map lamp side position of a one box type vehicle where the camera is installed), and the pitch angle α of the camera to the vertically downward direction is defined in five levels of 0.1, 0.2, 0.3, 0.4, 0.5 radians with no roll angle and no yaw angle.
Resolution of the camera is 320 pixels in width by 240 pixels in height, and a frame rate is 0.2 ms/frame.
The road surface is evenly flat with a rectangular paint mark of 2 meters in width by 5 meters in length. The vehicle is assumed to be turning at a corner of the right angle toward left at a speed of 22 km in ten seconds, which simulates a slow left turn at an intersection. The image is processed by a movement detector 11a that is described later in the embodiment section of the disclosure.
In the processing of the image, the four corners of the rectangular paint mark are specified as the characteristic points, and the translational movement of the vehicle has components only in the lateral directions (i.e., x axis in FIG. 3B), the front-rear directions (i.e., y axis in FIG. 3B). Further, the rotational movement of the vehicle has components only in the yaw direction (i.e., the rotation around z axis in FIG. 3B) with no change in the components in the pitch direction and the roll direction (i.e., the rotation around x and y axes in FIG. 3B).
As shown in the above table, the error of the rotational movement in the yaw direction increases when the pitch angle α of the camera is increased. Therefore, the camera having a greater pitch angle cannot accurately detect the movement of the apparatus and the vehicle.
On the other hand, when the camera has a smaller pitch angle α (i.e., the light axis of the camera is aligned closer to the vertically downward direction) for increasing detection accuracy of the apparatus movement, the camera captures a smaller range of the front field, thereby decreasing an obstacle detection capability. That is, the obstacle detection accuracy by the camera and the apparatus movement detection accuracy by the camera are in a trade-off relationship with each other. Therefore, the apparatus described above cannot improve the apparatus movement detection accuracy and the obstacle detection accuracy at the same time in a detection operation of the three-dimensional information of an object in the field.
Further, when the vehicle is moving forward, the characteristic point on a still object in the three-dimensional field comes closer toward the vehicle from a far side, and the optical flow of the characteristic point in the camera captured image runs downward in the image from an upper side of the image toward a lower side. Therefore, when the optical flow of the characteristic point on the road is calculated by tracing the characteristic point in the image, the characteristic point is traced in a direction that flows from an image data scarce side to an image data abundant side as shown in FIG. 13.
Therefore, in this case, an increased number of the characteristic points may possibly be detected on the lower side of the image because the image data are abundant on the lower side in comparison to the upper side. However, the characteristic points on the lower side immediately disappears from the image, thereby making it impossible to trace them for detecting the optical flow.

Field recognition apparatus, method for field recognition and program for the same


When a movable sleeve 11 on a cylinder moves upward, a combustion chamber 5 in a sealed state is formed. Mixed gas is explosively burnt within the combustion chamber 5 so as to drive a fastener out. A lock cylinder 22 is disposed beneath the movable sleeve 11. A lock piston 23 is housed within the lock cylinder 22 so as to be movable in an up/down direction. The upper end of the lock piston 23 is capable of being engaged with a holding member 12 which is interlocked with the movable sleeve 11. The lower portion of the lock cylinder is coupled to the combustion chamber via a gas tube 24. The gas tube 24 is provided with a check valve 25. The lock cylinder 22 is provided with an electromagnetic valve 27. The electromagnetic valve 27 opens upon the lapse of a predetermined time period after the combustion within the combustion chamber.

In some kinds of gas combustion type driving tools, combustible gas is injected into a combustion chamber sealed within a body, then mixed gas of the combustible gas and the air is stirred within the combustion chamber, and the mixed gas thus stirred is burnt within the combustion chamber to generate high-pressure combustion gas within the combustion chamber. The high-pressure combustion gas acts on a striking piston housed within a striking cylinder to impulsively drive the striking piston within the striking cylinder. A nail supplied to a nose portion beneath the body is driven into a steel plate or concrete by a driver coupled to the lower surface side of the striking piston. Such the combustion-gas driven driving machine is formed as a portable tool in a manner that a vessel such as a gas container filed with the combustible gas is attached within the tool and a battery acting as a power source for igniting the combustible gas is attached to the tool. Thus, the combustion-gas driven driving machine can perform the driving procedure of a nail or a pin without being restricted by a source of drive such as electric power or compressed air.
In the aforesaid gas combustion type driving tool, the striking piston is provided so as to be slidable in an up/down direction within the striking cylinder disposed within the body. The movable sleeve fitted on the outside of the striking cylinder so as to be movable in the up/down direction moves upward and abuts against a cylinder head provided above the striking cylinder to seal a space, whereby the combustion chamber can be configured. The movable sleeve is interlocked with a contact arm mechanism serving as a safety device. When the tip end of the contact arm is pressed against a member to be driven and is moved upward relatively with respect to the body, simultaneously the movable sleeve moves upward, whereby the combustion chamber sealed between the cylinder head and the striking cylinder is formed. When the contact arm restores to the original state, the movable sleeve also moves downward to open the combustion chamber.
The pulling operation of a trigger is made possible for the first time after the contact arm is pressed against the driven member and so the combustion chamber is formed. Further, if the trigger is not kept to be pulled, the movable sleeve moves downward and so the sealed state of the combustion chamber can not be held. JP-A-2004-074296 discloses an example of such a gas combustion type driving tool.
However, in the case where the trigger is released immediately after the trigger is pulled to drive the tool or in the case where the body separates instantaneously from the driven member due to the reaction at the time of the driving operation, there may arises a case that the contact arm also moves downward due to the urging force of a spring and hence the sealing state of the combustion chamber is lost. If the combustion chamber is opened at the early timing, since the pressure within the combustion chamber is not reduced sufficiently, there arises a phenomenon that the striking piston cannot return to the top dead center. In this case, the striking force at the next striking operation becomes insufficient and so a fastener rises from the driven member disadvantageously.


A door for an airbag module having an inflatable cushion, the airbag module being adapted to be used in a vehicle having an instrument panel with an airbag module opening, the door having an inner surface and an outer surface adapted to match the instrument panel, comprising: a first member depending away from the inner surface of the door, the first member being movably secured to the airbag module and remains secured to the module during deployment of the inflatable cushion; a second member depending away from the inner surface of the door, the second member being received within a flange opening of the airbag module; and a plurality of latch hooks depending away from the inner surface of the door, the plurality of latch hooks being configured to engage an opening in the airbag module, wherein the first member, the second member and the plurality of latch hooks are each configured to allow movement of the door in three separate directions with respect to the airbag module and wherein the second member and the plurality of latch hooks are configured to detach from the door during deployment of the inflatable cushion.

Airbag modules or supplemental inflatable restraint systems have become common in modem automobiles. An airbag module typically comprises an inflatable cushion and an inflator within a housing. The module is installed in a desired position within the vehicle, such as the steering wheel, the dashboard, the seat, the A-pillar, and other locations. The inflatable cushion is stored in a folded position within the housing in fluid communication with the inflator. In response to an activation event or occurrence, a sensor or sensing device provides a signal for activating the inflator. The inflator then provides a supply of inflating gas to the cushion deploying it from the housing.
As more and more vehicles are equipped with airbag modules, other vehicle components have been modified to accommodate the use of such systems. For example, most passenger side airbag module systems are disposed within and behind an instrument panel, which extends across the width of a vehicle compartment. During assembly, a conventional instrument panel in a vehicle having a passenger side airbag module system requires a discrete door which covers an opening formed in the instrument panel for the air bag cushion to deploy through upon actuation of the airbag module system. This separate door is designed to open in response to the force of the expanding air bag cushion. In other words as the pressure in the air bag cushion increases, an internal force is generated within the cushion and as the air bag cushion expands with this force, the door selectively separates from a portion of the module and the instrument panel as the air bag cushion deploys while another portion of the door remains secured to the module during deployment.
Typically, the manufacture of an instrument panel involves forming an opening in the instrument panel proximate to the airbag module system. This opening is then covered by a separate deployable door of the airbag module, which is secured to the instrument panel and faces the occupants of the vehicle. Thus, the instrument panel itself is manufactured in view of the shape and size of the door and the door is separately manufactured and installed within the opening in the instrument panel.
One difficulty encountered with passenger side airbag module covers is a poor fit to finish in the vehicle's instrument panel in which the passenger side airbags are installed. For example, uneven airbag cover to instrument panel gaps and non-flush conditions sometimes occur simply because the covers are fixedly mounted or permanently secured to the airbag canister with no adjusting movement therebetween. Therefore, if the module must be moved or adjusted in order to secure it in its desired location within the vehicle the cover fixedly secured thereto also moves. In addition, and if there is no tolerance or play between the cover and the housing of the module movement of the module will cause movement of the cover, which may provide the undesirable gaps or non-flush conditions mentioned above. This is particularly the case if the cover is in a desired position with respect to the instrument panel prior to movement or adjustment of the module in order to secure to the instrument panel or structural beam of the vehicle. The undesirable effects may be further exacerbated if only one end of the module needs to be adjusted to perform the securement step.

Cover for airbag module and method of making


The apparatus includes a sign and clips which support it. The sign is installed against the wall of the opening into a hazardous, confined space. The sign is a strip of flexible signboard with indicia applied to both broad surfaces. There are several presentations of the message of the sign on each side with adjacent presentations inverted. The clips are attached to the wall of the opening so that the sign is supported at its lower edge to prevent it from falling into the space. The ends of the sign overlap so that a sign of one length is usable in a range of sizes of manholes.

1. Field
The subject invention is in the field of signs and posters, particularly signs related to instructions about uses of exits and entries and authorization for and restrictions of such uses. More particularly, it is in the field of such signs which are easily and readily attachably installed and removed.
2. Prior Art
There is much prior art in this more particular field, patented and not. However, the need met by the subject invention is the result of recent legislation that requires that specific signs be installed in the entrances to confined spaces in which various hazards may exist, hazards which can be much more safely dealt with by personnel who have been trained and certified to do so. It is required that the signs be such that it is virtually impossible for a user not to notice the sign and be able to read it. Further, this requirement must be met without restrictions of the entrance. It is also required that the sign be easily and readily removed to limit damage to it during use of the entrance and easily and readily reinstalled when use is completed on each occasion. The primary objective of the subject invention is that it meet the legislated requirement as described. Secondary objectives are that the sign be durable and economical to manufacture and use.

Sign for use in entrance of hazardous confined space


The object of the present invention is to provide an electrostatic chuck in which the surface can be kept smooth after being exposed to plasma, so as to protect a material to be clamped such as a silicon wafer from being contaminated with particles, and which is excellent in clamping and releasing a material to be clamped. According to the present invention, there is provided an electrostatic chuck comprising a dielectric material in which alumina is 99.4 wt % or more, titanium oxide is more than 0.2 wt % and equal to or less than 0.6 wt %, whose average particle diameter is 2 μm or less, and whose volume resistivity is 108-1011 Ωcm in room temperature, wherein the electrostatic chuck is used in a low temperature of 100° C. or less.

1. Field of the Invention
The present invention relates to an electrostatic chuck for clamping and fixing a material to be clamped such as a semiconductor wafer or a glass substrate for an FPD with electrostatic force.
2. Description of Prior Art
Conventionally, a ceramic dielectric material of an electrostatic chuck is provided for the purpose of controlling the electrical characteristics (See Document 1).
However, if the ceramic structure is exposed to a plasma atmosphere, the structure is subject to corrosion, and the surface roughness is deteriorated. Consequently, there are some cases where variations in the contact state between the surface of the electrostatic chuck and the wafer occur over time, or there are other cases where grains are disjoined from a sintered body and the disjoined grain particles cause the wiring of an LSI circuit to be shorted.
In another conventional example, an alumina ceramic material having a particle diameter of 2 μm or less and a relative density of 99.9% in which the plasma-resistance is improved is applied to an electrostatic chuck (See Document 2). However, in this example, even if the plasma-resistance is improved, there is no description of the electrical characteristics, and it is impossible to perform fundamental functions of a Johnsen-Rahbeck electrostatic chuck which enables great clamping force.
Also, an alumina ceramic which contains titanium oxide of 0.1-1 wt % and has volume resistivity of 100-104 Ωcm has been proposed (See Document 3). However, in this case, it is impossible to obtain electrical characteristics for performing functions of an electrostatic chuck.
Also, an electrostatic chuck in which the volume resistivity is reduced by adding titanium oxide of 0.5-2 wt % to an alumina ceramic has been proposed (See Document 4). This document has disclosed that the resistivity is not reduced in a case of less than 0.5 wt %, and too much current flows in a case of 2.0 wt % or more. It has also disclosed that titanium oxide is precipitated in the grain boundary of alumina ceramics. Although an additive of at least 0.5 wt % is required to reduce the volume resistivity, such an amount of the additive is too much for an electrostatic chuck which requires a strict limitation in contamination with respect to a material to be clamped.
Also, there has been proposed an electrostatic chuck in which alumina of 99% or more is contained, the average particle diameter is 1-3 μm, and the volume resistivity is 108-1011 Ωcm in a temperature of 300-500° C. (See Document 5). However, there is no description of properties of an dielectric material required for an electrostatic chuck which is used in another temperature range, for example, a relatively low temperature such as 100° C. or less.    Document 1: Japanese Patent No. 3084869    Document 2: Japanese Patent Application Publication No. 10-279349    Document 3: Japanese Patent Application Publication No. 2004-18296    Document 4: Japanese Pre-grant Publication No. 6-97675    Document 5: Japanese Patent Application Publication No. 11-312729
The object of the present invention is to provide an electrostatic chuck in which the surface can be kept smooth after being exposed to plasma, so as to protect a material to be clamped such as a silicon wafer from being contaminated with particles, and which is excellent in clamping and releasing a material to be clamped.