In a code division multiple access communication system providing a plurality of communication type services between a first unit (100) and a second communicating unit (200) by time-multiplexing a plurality of data channel signals (101, 102, 103) associated with the plurality of communication type services to produce a time-multiplexed data channel signal (106) which are combined to produce a combined signal (136). Combined signal (136) is transmitted from first unit (100) to be received by second unit (200). After producing a code-demultiplexed time-multiplexed data channel signal (218), and a plurality of signal-to-interference ratios estimated based on a plurality of time-multiplexed portions of signal (218), a plurality of power control thresholds corresponding to the plurality of communication type services are compared to the plurality of signal-to-interference ratios. As a result, producing a plurality of power control data bits corresponding to the plurality of communication type services based.

A code division multiple access (CDMA) communication system may include a base station and a number of mobile stations. The base stations adjust power levels of a number of communication channel signals targeted for a corresponding number of mobile stations and at least a control channel signal, and code-multiplexes the signals to produce a combined signal. The base station transmits the combined signal via a wireless communication downlink from the base stations to the mobile stations.
When a mobile station receives the combined signal, it code-demultiplexes the received combined signal according to its assigned multiplexing code to recover its targeted communication channel information. The mobile station measures a signal-to-interference ratio of the code-demultiplexed control channel signal or communication channel signal or both, and compares the result to a power control threshold to produce a power control data bit. The mobile station transmits the power control data bit to the base station via a wireless communication uplink. The base station adjusts the power level of the communication channel signal targeted for the mobile station according to the status of the power control data bit.
The level of the power control threshold is independently determined such that when the signal-to-interference ratio of the received signal is at a level comparable to the threshold, the signal may be demodulated at an adequate frame error rate in the receiver section of the mobile station. The level of the power control threshold is dependent on the level of the adequate frame error rate as determined by the communication system standard. The power level of the communication channel signal is adjusted to account for channel variations such that an adequate frame error rate is maintained. Furthermore, the power level of the communication channel signal is adjusted to maintain a comparable power levels among all mobile stations in the communication system.
Similarly, the base station also compares the signal-to-interference ratio of a signal transmitted from the mobile station in the uplink to a power control threshold. A power level control data bit as a result of the comparison is transmitted to the mobile station in a downlink traffic channel to change the mobile station transmit power level. If the signal-to-interference ratio is less than the threshold, power control data bit indicates an increase of power level, and if conversely, it indicates a power level decrease.
In the prior art, communication channels have been of the same type such as a voice channel type. Therefore, a power control data bit and a power control threshold have been sufficient to control power level of each channel signal to maintain an adequate communication link. Recently, various telecommunication standard committees have proposed a CDMA communication system that provides a number of communication type services simultaneously. Such a system is commonly know as the 3G-CDMA system. In the proposed CDMA communication system, voice, video and data channel types signals are code-multiplexed, or code and time multiplexed to produce a combined signal. Documents regarding such proposed communication systems and other information may be obtained by contacting European Telecommunication Standard Institute (ETSI), located European Telecommunications Standards Institute, 650 Rt. des Lucioles-Sophia Antipolis, Valbonne-FRANCE. The combined signal may be transmitted from a mobile station on an uplink or from a base station on a downlink. The mobile station and the base station simultaneously in a single connection communicate voice, video and data information. Normally, a communication channel of voice type signal has a frame error rate requirement that is different than frame error rates of other types of communication channels, such as video and data types. As a result, a common power control data bit and a common power control threshold are not sufficient to control power level of all channel types signals to maintain an adequate communication link for services of all channel types.
Therefore, there is a need for a power control scheme that solves the problem of satisfying different requirements of communicating signals of various channel types.

Method and apparatus for communicating signals of various channel types in CDMA communication system


Provided is a small-sized electrophotographic apparatus for which maintenance such as disposal of a jam of sheets, replacement of consumables including toner, or replacement of components to be periodically replaced can be facilitated.

The present invention relates to an image forming apparatus such as a copying machine, a printer, a facsimile system which forms a color image with the use of electrophotography, and in particular, to an electrophotographic apparatus for forming a color image with the use of a plurality of color toners.
With the electrophotography, a light beam is projected from an exposure means onto a photosensitive medium which is uniformly charged, so as to form a latent image corresponding to image data, and toner is stuck to the latent image on the photosensitive medium so as to develop the latent image. The thus obtained toner image is transferred onto and fixed on a recording medium.
It is noted here that explanation will be hereinbelow made so as to use the recording medium as a sheet. However, the recording medium should not be limited to the sheet alone but there may be used a sheet-like recording medium made of any of various materials including plastic.
In order to form a color image, a plurality of color toners such as yellow Y, magenta M, cyan C and black K are superposed one upon another so as to form the image.
There are two kinds of color image forming systems, such as a repeated developing system in which development is repeated on a single photosensitive medium with color toners so as to form a color image, and a simultaneous developing system in which developments are simultaneously carried out on a plurality of photosensitive mediums with color toners so as to form a color image.
The repeated development system is the one in which a single photosensitive medium is used for forming a color image, and as typical examples, there are a transfer drum system and an intermediate transfer medium system.
In the transfer drum system, a plurality of developing means for developing images with different color toners are arranged around a photosensitive medium, together with a transfer drum for winding a recording medium thereon, and different color images formed on the photosensitive medium are transferred one by one onto the recording medium. This operation is repeated for the different color images which are superposed one upon another on a recording medium so as to obtain a color image.
In the intermediate transfer medium system, a plurality of developing means for developing images with different color toners are arranged around a photosensitive medium, together with an intermediate transfer medium, and toner color images formed on the photosensitive medium are transferred one by one onto the intermediate transfer medium. This transfer is repeated for different color images so as to superpose these images on the intermediate transfer medium in order to form a color image which is then transferred onto a medium on which the color image is fixed.
The transfer drum system is apt to cause the quality of an obtained color image to be affected by a kind of sheets since different color toner images are directly superposed on a recording medium, that is, the intermediate transfer medium system is more excellent in view of the formation of a color image on any of various kinds of sheets including a cardboard.
However, even in the intermediate transfer medium system, since different toner color images of, for example, yellow Y, magenta M, cyan C and black K are formed one by one on the photosensitive medium, and are then transferred onto the intermediate transfer medium, being superposed one upon each other, a time which is four times as long as that required for formation of a monochromatic image is required.
The simultaneous developing system simultaneously forms color toner images respectively on a plurality of photosensitive mediums for respective different colors, and transfers the different color toner images in association with a conveyance of a sheet so as to form a color image. Thus, this developing system is also called as a tandem system.
The tandem system incorporates an image forming means including a photosensitive medium, a charging means, an exposure means, a developing means and a cleaner means for each color, and accordingly, four image forming means are required for forming a color image with color toners of yellow Y, magenta M, cyan C and black K.
In the tandem system, different toner color images are formed by four independent image forming means, simultaneously in parallel with each other, and are then transferred onto an intermediate transfer medium or a sheet. In the tandem system, since different toner color images are simultaneously superposed one upon another, a color image can be formed by a time nearly equal to that required for formation of a monochromatic image, and accordingly, this system is preferable for high speed printing of a color image.
It is noted that the tandem system is sorted into a direct transfer system and an intermediate transfer medium system in view of a diagnostic criteria whether different color images are directly superposed with one other on a recording medium or are superposed with one other a transfer medium. The intermediate transfer medium system is advantageous for different kinds of sheets, similar to the repeated development system.
These years, there have been increased demands for colorization of documents in offices and accordingly, color printers have been rapidly spread in use. Further, it has been desired to increase the printing speed, and accordingly, tandem system color printers have been spot-lighted.
However, since the tandem system color printer inevitably incorporates four image forming means, the miniaturization of the printer is difficult, that is, it has a size which is relatively larger than that of a repeated development system color printer.
In particular, in a tandem type system color printer in which image forming means are horizontally laid as conventionally usual, an increased size of the printer causes its occupied floor area to be larger in the case of installation thereof in an office.
Thus, it has been proposed a tandem system color printer in which image forming means are arranged in a vertical direction in order to decrease the size of the printer and to reduce the occupied floor area thereof.
It has been known a tandem system color printer in which a laser light source is used as an exposure means, and four image forming means are arranged in a vertical direction along a straight part of an intermediate transfer medium (as disclosed, for example, JP-A-2001-134042). In this tandem system color printer, a laser exposure means is mounted so as to be stationary, and photosensitive drums are mounted on a common member so as to be grouped in one unit in order to ensure a high degree of accuracy. Developing means are removably mounted in front of the printer.
A tandem system color printer in which LED arrays are used as the exposure means, and four image forming means are stacked in a vertical direction along a straight part of an intermediate transfer medium has been also known (as disclosed in JP-A-2001-356548). In this tandem system color printer, the LED arrays are mounted to be stationary so as to ensure a high degree of accuracy. A process cartridge in which the photosensitive drums and the developing means are integrally incorporated is removably mounted in front of the printer.
It is noted that the image forming means are arranged in a vertical direction in the printer disclosed in JP-A-2001-134042 or JP-A-2001-356548 in order to decrease the size of the printer and to reduce the occupied floor area.
In the printer disclosed in JP-A-2001-134042, the developing means can be removed in front of the printer. However, a jam of sheets should be removed in rear of the printer, and accordingly, its manipulatability is unsatisfactory.
In the printer disclosed in JP-A-2001-356548, a sheet tray is set in the upper part of the printer, and further, sheets are discharged onto a discharge tray in the upper part of the printer. In this configuration, a process cartridge in which a photosensitive drum and a developing means are integrally incorporated can be removed in front of the printer, and a jam of sheets can be removed at the top surface of the printer. However, since the sheet tray overhangs at the top surface of the printer, the occupied floor area is increased. Further, the capacity of supply of sheets cannot be increased in comparison with a printer in which a sheet tray is set in the lower part of the printer. It is noted that this document also discloses an example in which a sheet tray is set in the lower part of a printer. Even in this configuration, the process cartridge can be removed in front of the printer. However, a jam of sheets should be removed in rear of the printer, and accordingly, its manipulatability is low.
Thus, in the tandem system color printer, such a configuration that the image forming means are arranged in a vertical direction is used in order to miniaturize the printer, and in the case of selection of an intermediate image transfer medium system in order to accept various kinds of sheets, the manipulatability for replacement of toners and removal of a jam of sheet becomes lower.

Abstract: Thus, there is provided a tandem type electrophotographic apparatus using an intermediate transfer belt, in which photosensitive drums are arranged in a vertical one row, the intermediate transfer belt is located on one side of the row of the photosensitive drums, the developing means are located on the other side of the row of the photosensitive drums, a transfer means for transfer a toner image from the intermediate transfer belt onto a recording medium is located above the row of the photosensitive drums, a recording medium conveying path composed of a vertical conveying path (a front opening door) for conveying a recording medium fed from the recording medium supply means, outside of the developing means and substantially in parallel with the intermediate transfer belt, a curved part and a horizontal conveying path for conveying the recording medium up to a transfer means in a substantially horizontal direction, and a fixing means for fixing a toner image transferred onto the recording medium is incorporated in the horizontal conveying path (a top surface opening door), downstream of the transfer means.


Systems and methods for damping cable common-mode energy in magnetic environments are provided. One system includes a damping arrangement having a transmission line within an electric (E) field environment and an energy damping device formed having a conductive plastic body and positioned adjacent a conductor of the transmission line. The energy damping device is configured to dampen common-mode energy induced within the transmission line by the E field environment.

The subject matter disclosed herein relates generally to systems and methods for damping common-mode energy, such as for damping transmission line common-modes in Magnetic Resonance Imaging (MRI) systems.
Electric (E) fields generated by a system can induce currents and voltages that can interfere with the operation of that system. For example, MRI systems include a magnet, such as a superconducting magnet that generates a temporally constant (i.e., uniform and static) primary or main magnetic field. MRI data acquisition is accomplished by exciting magnetic moments within the primary magnetic field using radio-frequency RF coils. For example, in order to image a region of interest, the magnetic gradient coils are energized to impose a magnetic gradient to the primary magnetic field. RF transmit coils are then pulsed to create RF magnetic field pulses in a bore of an MRI scanner in order to acquire MR images of the region of interest using, for example, a phased array of RF receiver coils. The resultant image that is generated shows the structure and function of the region of interest.
In MRI systems, the RF coils, besides generating the RF magnetic fields needed for MRI, also generate E fields that induce currents and voltages within transmission lines (e.g., coaxial cables) connected to the one or more RF transmit (e.g., body) or receive coils. These induced voltages and currents, such as common-mode currents can interfere with the operation of the MRI system, such as with the tuning and matching of the RF coils in the MRI system. In order to suppress or dampen these induced modes, one or more balanced-unbalanced networks (baluns) are typically connected in series with the cable shield. However, these baluns are only narrow band parallel resonators and also get hot due to the high internal current during transmit pulses of the system.

Systems and methods for damping common-mode energy


Inhibitors for matrix metalloproteases, pharmaceutical compositions containing them, and a process for using them to treat a variety of physiological conditions. The compounds of the invention have the generalized formula ##STR1## wherein each T is a substituted group; x is 0, 1, or 2; the group D represents ##STR2## the group R6 represents a variety of possible substituent groups on the carbon chain between D and G, and the group G represents M, ##STR3## in which M represents --CO.sub.2 H, --CON(R.sup.11).sub.2, or --CO.sub.2 R.sup.12 ; and R.sup.13 represents any of the side chains of the 19 noncyclic naturally occurring amino acids.

The matrix metalloproteases (aka. matrix metalloendo-proteinases or MMPs) are a family of zinc endoproteinases which include, but are not limited to, interstitial collagenase (aka. MMP-1), stromelysin (aka. proteoglycanase, transin, or MMP-3), gelatinase A (aka. 72 kDa-gelatinase or MMP-2) and gelatinase B (aka. 95 kDa-gelatinase or MMP-9). These MMPs are secreted by a variety of cells including fibroblasts and chondrocytes, along with natural proteinatious inhibitors known as TIMPs (Tissue Inhibitor of MetalloProteinase).
All of these MMPs are capable of destroying a variety of connective tissue components of articular cartilage or basement membranes. Each MMP is secreted as an inactive proenzyme which must be cleaved in a subsequent step before it is able to exert its own proteolytic activity. In addition to the matrix destroying effect, certain of these MMPs such as MMP-3 have been implemented as the in vivo activator for other MMPs such as MMP-1 and MMP-9 (A. Ho, H. Nagase, Arch Biochem Biophys., 267, 211-16 (1988); Y. Ogata, J. J. Enghild, H. Nagase, J. Biol. Chem., 267, 3581-84 (1992)). Thus, a cascade of proteolytic activity can be initiated by an excess of MMP-3. It follows that specific MMP-3 inhibitors should limit the activity of other MMPs that are not directly inhibited by such inhibitors.
It has also been reported that MMP-3 can cleave and thereby inactivate the endogenous inhibitors of other proteinases such as elastase (P. G. Winyard, Z. Zhang, K. Chidwick, D. R. Blake, R. W. Carrell G., Murphy, FEBS Letts., 279, 1, 91-94 (1991)). Inhibitors of MMP-3 could thus influence the activity of other destructive proteinases by modifying the level of their endogenous inhibitors.
A number of diseases are thought to be mediated by excess or undesired matrix-destroying metalloprotease activity or by an imbalance in the ratio of the MMPs to the TIMPs. These include: a) osteoarthritis (Woessner, et al., J. Biochelogical Chem., 259(6), 3633-3638 (1984); J. Rheumatol., 10, 852-860 (1883)), b) rheumatoid arthritis (D. E. Mullins, et al., Biochim. Biophys. Acta, 695, 117-214 (1983); Arthritis and Rheumatism, 20, 1231-1239 (1977); Arthritis and Rheumatism, 34, 1076-1105 (1991)), c) septic arthritis (R. J. Williams, et al., Arthr. Rheum., 33, 533-41 (1990)), d) tumor metastasis (R. Reich, et al., Cancer Res., 48, 3307-3312 (1988), and L. M. Matrisian, et al., Proc. Nat'l. Acad. Sci., USA, 83, 9413-7 (1986)), e) periodontal diseases (C. M. Overall, et al., J. Periodontal Res., 22, 81-88 (1987)), f) corneal ulceration (F. R. Burns, et al., Invest. Opthalmol., 30, 1569-1575 (1989)), g) proteinuria (W. H. Baricos, et al., Biochem. J., 254, 609-612 (1988)), h) coronary thrombosis from atherosclerotic plaque rupture (A. M. Henney, et al., Proc. Nat'l. Acad. Sci. USA, 88, 8154-8158 (1991)), i) aneurysmal aortic disease (N. Vine and J. T. Powell, Clin. Sci., 81, 233-9 (1991)), j) birth control (J. F. Woessner, et al., Steroids, 54, 491-499 (1989)), k) dystrophobic epidermolysis bullosa (A. Kronberger, et al., J. Invest. Dermatol., 79, 208-211 (1982)), and l) degenerative cartilage loss following traumatic joint injury, conditions leading to inflammatory responses, osteopenias mediated by MMP activity, tempero mandibular joint disease, demyelating diseases of the nervous system, etc. (J. Neurochem., 50, 688-694 (1988)).
The need for new therapies is especially important in the case of arthritic diseases. The primary disabling effect of oeteoarthritis (OA), rheumatoid arthritis (RA) and septic arthritis is the progressive loss of articular cartilage and thereby normal joint function. No marketed pharmaceutical agent is able to prevent or slow this cartilage loss, although nonsteroidal antiinflammatory drugs (NSAIDs) have been given to control pain and swelling. The end result of these diseases is total loss of joint function which is only treatable by joint replacement surgery. MMP inhibitors are expected to halt or reverse the progression of cartilage loss and obviate or delay surgical intervention.
Several inhibitors of MMPs have been described in the literature. See, for example, U.S. Pat. No. 4,599,361; U.S. Pat. No. 5,190,937; EP 0574 758 A1, published Dec. 22, 1993; EP 026 436 A1 published Aug. 3, 1988; and EP 0520 573 A1, published Dec. 30, 1992. These compounds have peptide backbones with a zinc complexing group (hydroxamic acid, thiol, carboxylic acid or phosphinic acid) at one end and a variety of sidechains, both those found in the natural amino acids as well as those with more novel functional groups. Such small peptides are usually poorly absorbed, exhibiting low oral bioavailability. They are also subject to rapid proteolytic metabolism, thus having short half lives. See, for example, a search for orally active peptide-based renin inhibitors in which the best compound had a bioavailability of only 14% in monkeys: Saul H. Rosenberg, et al., J. Med. Chem., 36, 449-459 (1993).
Certain 3-biphenoylpropanoic and 4-biaryloylbutanoic acids are described in the literature as anti-inflammatory, anti-platelet aggregation, anti-phlogistic, anti-proliferative, hypolipidemic, antirheumatic, analgesic, and hypocholesterolemic agents. In none of these examples is a reference made to MMP inhibition as a mechanism for the claimed therapeutic effect. Certain related compounds are also used as intermediates in the preparation of liquid crystals.
Specifically U.S. Pat. No. 3,784,701 claims certain substituted benzoylpropionic acids to treat inflammation and pain. These compounds include 3-biphenoylpropanoic acid (aka fenbufen) shown below. ##STR4##
R. G. Child, et al., J. Pharm. Sci., 66, 466-476 (1977) describes structure-activity relationships of several analogs of fenbufen. These include several compounds in which the biphenyl ring system is substituted or the propanoic acid portion is substituted with phenyl, halogen, hydroxyl or methyl, or the carboxylic acid or carbonyl functions are converted to a variety of derivatives. No compounds are described which contain a 4'-substituted biphenyl and a substituted propanoic acid portion combined in one molecule. The phenyl (compounds XLIV and LXXVII) and methyl (compound XLVIII) substituted compounds shown below were described as inactive. ##STR5##
K. K. Kameo, et al., Chem. Pharm. Bull., 36, 2050-2060 and JP patent 62132825 describe certain substituted 3-biphenoylpropionic acid derivatives and analogs thereof including the following. Various compounds with other substituents on the propionic acid portion are described, but they do not contain biphenyl residues. ##STR6##
H. Cousse, et al., Eur. J. Med. Chem., 22, 45-57 (1987) describe the following methyl and methylene substituted 3-biphenoylpropanoic and -propenoic acids. The corresponding compounds in which the carbonyl is replaced with either CHOH or CH.sub.2 are also described. ##STR7##
German Patent Application No. 19 57 750 of Tomae also describes certain of the above methylene substituted biphenoylpropanoic acids.
M. A. El-Hashsh, et al., Revue Roum. Chim., 23, 1581-1588 (1978) describe products derived from .beta.-aroyl-acrylic acid epoxides including the following biphenyl compound. No compounds substituted on the biphenyl portion are described. ##STR8##
T. Kitamura, et al., Japanese Patent Application No. 84-65795 840404 describes certain biphenyl compounds used as intermediates for the production of liquid crystals including the following. The biphenyl is not substituted in these intermediates. ##STR9##
German Patent No. 28 54 475 uses the following compound as an intermediate. The biphenyl group is not substituted. ##STR10##
A. Sammou, et al., Egypt J. Chem., 15, 311-327 (1972) and J. Couquelet, et al., Bull. Soc. Chim. Fr., 9, 3196-9 (1971) describe certain dialkylamino substituted biphenoylpropanoic acids including the following. In no case is the biphenyl group substituted. ##STR11##
It would be desirable to have effective MMP inhibitors which possess improved bioavailablity and biological stability relative to the peptide-based compounds of the prior art, and which can be optimized for use against particular target MMPs. Such compounds are the subject of the present application.

Substituted 4-biarylbutyric acid derivatives as matrix metalloprotease inhibitors


A buckle for vehicle safety belt systems provided with a pretensioner engaging the buckle, is prevented by a locking pawl (42) from unintentional opening at the beginning and at the end of a pretensioning stroke. By the effect of its mass inertia at the start of the pretensioning stroke an inertial body moves the locking pawl (42) into a locking position in which the release button (30) is prevented from moving in a direction relative to the base in the pretensioning direction (R). Due to the location of its center of gravity relative to its mounting position the locking pawl (42) at the end of the pretensioning stroke remains in the locking position and is decoupled from the inertial body (56).

The present invention relates to a buckle for vehicle safety belt systems provided with a pretensioner engaging the buckle.
Buckles for safety belt systems are known in a great many different versions. In one configuration, which has become popular, the load-bearing base of the buckle has an insertion path for the tongue of the belt and a latch slidably guided or swivably mounted on the base transversely to the insertion path to interact with a detent opening of the tongue. A locking member slidably guided parallel to the insertion path in the base holds the latch in its latched position as long as the release button, which is also slidably guided parallel to the insertion path on the base, is in its rest position. This release button is coupled to the locking member, to move it, when actuated, to a release position in which the latch releases from the detent opening of the tongue.
Using such a lock in safety belt systems having a pretensioner is no problem when the pretensioning force engages, for example, on the belt retractor. Pretensioners have also been proposed which are effective between the buckle and its fastening point on the vehicle body or a vehicle seat. Pretensioners of this kind shorten the distance between the fastening point of the buckle and the buckle itself by a few centimeters, for example 10 cm.
The force required for pretensioning can be produced mechanically by means of strongly dimensioned spring or pyrotechnically. If the pretensioning force is sufficiently high, particularly when pyrotechnical pretensioning drive means are used, it may occur in certain cases that the buckle automatically opens at the beginning or at the end of the pretensioning stroke.
Automatic opening of the buckle as a consequence of the pretensioning stroke is attributed to the mass inertia of the release button and of any components acting thereon. For example, at the end of its pretensioning stroke, the release button tends to continue its movement in the pretensioning direction corresponding to the operating direction of the release button.
One way of counteracting a continued movement of the release button under the effect of the forces of inertia is to provide a locking pawl which under the influence of its mass inertia is movable transversely to the direction of pretensioning and which at the end of a pretensioning stroke, when the buckle is abruptly decelerated, assumes a position in which it prevents further movement of the release button in to its release position. A buckle designed on the basis of this principle is disclosed, for instance, by U.S. Pat. No. 5,097,571. Activation of the locking pawl involves a movement of the release button in the direction of the release position; accordingly, the release button must implement some idle travel. The locking pawl prevents the release button from being shifted into the release position. It must be ensured that the locking pawl obtains its locking position before the release button moves past the point at which locking by means of the locking pawl is no longer possible. This requirement restricts the freedom of selecting and dimensioning components for the buckle.
Other known means of counteracting movement of the release button on a pretensioning stroke consist in using compensating inertial bodies, however, this is often disqualified, particularly when space availability is limited.


A telephone system and method that enables a telephone to handle more call appearances that it has call appearance keys. The telephone system contains a display and general purpose keys that are used to respond to prompts shown on the display. When the telephone system receives an incoming call that is not assigned to a dedicated call appearance key, then the system places a prompt on the display. The prompt identifies the line upon which the telephone call is received by placing an identifying name, number or telephone location on the display. The prompt is placed adjacent to one of the general purpose keys so that the prompt is clearly associated with only one of the general purpose keys. The system then assigns that general purpose key to the telephone line addressed by the prompt. As a result, the general purpose key becomes a call appearance key and a person using the telephone system can complete a connection between that telephone an incoming call by pressing that general purpose key.

1. Field of the Invention
The present invention relates to telephone systems and related methods that use a limited number of call appearance keys yet receive and process numerous call appearances in excess of the call appearance keys available.
2. Description of the Prior Art
Many businesses have multiple telephone lines. In fact, it is common in a business for most every employee to have his/her own telephone number. Often businesses buy telephone systems that use a central telephone unit located at a receptionist's desk or at the front desk of the business. The central telephone unit receives all the incoming call appearances directed to employees of that business. The receptionist fields the incoming call and then directs the call to the appropriate line in the system.
The central telephone unit often has dedicated call appearance keys, wherein each call appearance key is assigned to a different telephone number. As a result, a receptionist can tell what number was dialed by viewing the call appearance key that flashes when an incoming call appearance is received. If the telephone number dialed is specific to one of the business' employees, the receptionist can tell for whom a received call belongs and can either answer the call or direct the call accordingly. For example, in a company Mr. Jones may have a telephone with his own telephone number. When a person calls the company using Mr. Jones' telephone number a specific call appearance key will flash at the receptionist's central telephone unit. Recognizing that the incoming call was received on Mr. Jones' number, the receptionist can either answer the call on behalf of Mr. Jones or direct the call to Mr. Jones directly.
As a business grows, the number of telephone lines used by that business may eventually outnumber the call appearance keys present on the receptionist's central telephone unit. When this happens, many different telephone lines are often grouped together at the same call appearance key on the central telephone unit. As a result, the receptionist can no longer tell from what number an incoming call appearance is being received. Consequently, the receptionist must answer the incoming call and must inquire about its purpose and destination. This places much larger duties on the receptionist and results in many calls being placed on hold for longer periods of time.
A need therefore exists in the art for a central telephone unit that is specifically designed to handle more incoming call appearances than there are dedicated call appearance keys. As such, a receptionist can tell for whom an incoming call is directed without a company having to upgrade to more sophisticated telephone equipment having a larger dedicated call appearance capacity.

System and method for processing multiple call appearances using a limited display


An optical switch is disclosed which includes hollow waveguide structures having cantilevered beam deflectors to couple light out of the waveguide plane. An array of such waveguides with deflector combinations may be fabricated on a substrate. By combining substrates, devices such as all-optical cross bar switches, image display and scanning devices may be created.

This invention generally relates to the field of optical switching. More specifically, the present invention relates to optical systems comprising hollow optical waveguides and micro-mechanical deflectable mirrors.
Optical switching is a fundamental operation that is useful in optical communications, optical memory, and optical displays. In its most basic form, optical switching involves spatial redirection of information-carrying optical waves. FIG. 1 (prior art) shows a simple and generic optical switch 100. This one-inputxe2x80x94two-output optical switch directs input optical signal 101 to one or both of the two optical output ports, output 1102 and output 2103, under the command of a control signal 104.
This switch may be generalized to N-output ports. FIG. 2 (prior art) illustrates how a Ixc3x97N switch 200 may be constructed from multitude of 1xc3x972 optical switches 100. In this particular illustration, N equals 6. In the Ixc3x97N configuration, a switch may be used in a signal distribution network. Alternatively, by sequentially switching the optical signal to the N output ports that are arranged in a 2-D spatial array, the switch may be used in a display device where the input optical signal contains image information. The same switch may also be used to access different spatial locations in an optical memory.
A basic switch 300 may also be generalized to contain several input ports as illustrated in FIG. 3 (prior art). Again, a simple switch may contain two input ports, input 1301 and input 2302, as well as two output ports, output 1303 and output 2304. This may be a generalization of switch 100 shown in FIG. 1. Under the direction of an external control signal 305, each of the input signals, 301 and 302 may be directed to one or both of the output ports, 303 and 304 respectively. When a single input is distributed to both output ports, the operation is called xe2x80x9cbroadcast or fan-out.xe2x80x9d When both input signals are directed to a single output port, the operation is termed xe2x80x9cconcentration or fan-in.xe2x80x9d When each output port receives one or the other of the input signals, the operation is termed xe2x80x9cpermutationxe2x80x9d.
This switch may be generalized when the number of input signals and output ports exceed two. In general, the number of input signals, say M, and the number of output ports, say N, do not have to be equal. Such an Mxc3x97N optical switch forms the heart of an optical switching network in a communication system or the interconnection fabric inside a high performance computing system. Again, one skilled in the art can easily see how such an Mxc3x97N optical switch may be constructed from M optical,switches, each of which is a Ixc3x97N switch of the type shown in FIG. 2. Corresponding output lines from each of the M such switches may be combined to generate one of N output lines.
Performance parameters associated with such Mxc3x97N optical switches includes but is not limited to: the size of the switch (values of M and N); the bandwidth of the optical signals the switch can carry; the rate at which the signals can be redirected or the switch can be reconfigured; the optical efficiency of the switch (loss); the isolation between ports (cross talk); the ability to perform a broadcast operation; the ability to handle optical signals of different formats (analog, digital, AM, FM, PM, multiple wavelengths); the complexity of the control signal interface; the ease of interfacing to optical fibers; the overall size; the weight; the power consumption; the mechanical stability; and the ease of manufacturing. Each performance parameter is not equally important to different applications. In fact, some of them may not be relevant to certain applications at all. For example, the ease of interfacing to optical fibers may not be relevant to display applications. To the extent that some of these parameters may not be optimized simultaneously, the trade-off between them may be governed by the specific applications for which they are being designed.
Given the widespread applications of optical switches, it is not surprising that over the years a number of different designs have been proposed and implemented. These designs primarily fall in two categories: designs where light propagates in guided wave structures inside the switch and designs where light propagates in free space inside the switch.
Guided Wave Optical Switches
FIG. 4A and FIG. 4B (prior art) show schematic diagrams of a simple 1xc3x972 optical switch involving mechanical movements and using optical fibers. As illustrated, the type of switch may have an input fiber 402 and two output fibers 404 and 406, switched by mechanical movements 410 and 412. FIG. 4A shows input fiber 402 switched to output fiber 404 and FIG. 4B shows input fiber 402 switched to output fiber 406. This type of switch may be extremely simple to construct, have low loss, have very high isolation between ports, and carry full bandwidth available to optical fibers regardless of the format. However, this switch may be slow to reconfigure due the difficulty of moving a large mass, may not allow broadcast and may not be easily extendable to an Mxc3x97N switch. Still, such switches, due to their simplicity have found uses in fiber optic networks.
A second type of guided wave switches based on optical propagation in planar (integrated optic) waveguides and dynamic directional couplers is illustrated in FIG. 5 (prior art). This schematic diagram of a 1xc3x972 switch is based on a directional coupler. Light from a single mode waveguide 520 may be coupled into another single mode waveguide 522 that is brought in close proximity, allowing interaction between each waveguide, 520 and 522, via evanescent field coupling. By controlling the phase of the evanescent wave in the intervening region using a control mechanism 510, the coupling efficiency may be modulated between 0 and 100% (for ideal devices). If the inputs 502 and 506 to both waveguides contain optical signals, the same switch may be made to behave like a 2xc3x972-permutation switch, where the outputs are illustrated as 504 and 508. The phase of the evanescent wave may be controlled at the control mechanism 510 via electrooptic effect or thermooptic effect. Several such 2xc3x972 switches may be combined in a tree-like structure to realize an Mxc3x97N permutation switch. Such integrated optic crossbar switches have been commercially available from a number of companies including Ericsson of Stockholm, Sweden, Lucent of Murray Hill, N.J., and Worldwide Telecommunications Corporation (NTT) of Tokyo, Japan. These switches may be compact, switched extremely fast (if electrically controlled), have good isolation, and carry high bandwidth optical signals. However, these switches may also be difficult to couple to fibers, be environmentally sensitive, not achieve broadcast functionality, and not extend easily to large sizes without consuming a large integrated optic chip area.
FIG. 6 (prior art) illustrates an experimental approach to integrated optical switches utilizing electrooptically-activated Bragg reflectors embedded into waveguide junctions. Two one-dimensional arrays including a first input optical waveguide 610, a second input optical waveguide 612, a first output optical waveguide 614, and a second output optical waveguide 616 may be arranged orthogonally oriented to each other in a single plane as shown in FIG. 6. With no electric field activating a grating (620, 622, 624, or 626) at a junction, light injected in a waveguide may continue propagating along it. When the grating is activated, light may be scattered into the output waveguide that crosses the input waveguide. FIG. 6 shows this switch structure schematically. The figure shows a 2xc3x972 switch where input signal 1602 is coupled to output port B 608 and input signal 2604 is coupled to output port A 606. This is achieved by activating gratings 624 and 622, while leaving gratings 620 and 626 deactivated.
The advantages and disadvantages of this switch design are somewhat similar to the design shown in FIG. 4. Since this design involves waveguides at right angles, it may lead to a more compact switch. However, the cross talk characteristics may be distinctly inferior to the previous design and the build up of cross talk may limit the size of the switch.
Free Space Optical Switches
FIG. 7 (prior art) is a diagram of a free space optical switches. With free space optical switch designs, light beams propagate in free space without any guiding structures. Usually such systems employ lenses to keep the divergence of optical beams in check. An Mxc3x97N free space optical cross bar switch is easiest to understand conceptually.
FIG. 7 does not show any intervening lenses. The lenses may consist of anamorphic (cylindrical) lenses that perform imaging operations along one direction and collimation or focusing along the orthogonal axis. The two-dimensional switch consists of binary amplitude Spatial Light Modulators (SLM) 704, where each of the 4xc3x976 array of pixels may be transmitting or opaque. By controlling the transmittance of each of the pixels, any one of the 4 inputs 702 may be connected to any of the six outputs 706. This fully generalized switch may perform an arbitrary permutation, broadcast, or perform fan-in operation(s). This switch however, usually has low throughput (high loss). Each input channel is broadcast to all output channels. In a permutation operation, only one of the 6 pixels in a row in FIG. 7 above will be transmitting, hence the rest of the light is lost. This light loss is directly proportional to the size of the switch and hence for large size switches ( greater than 100), the losses may be unacceptable. A second undesirable feature is the slow switching speed of most 2-D SLM""s. This limits the reconfiguration time for the switch. The switch is relatively bulky and may require coupling from and to fibers. The generation and delivery of control signals may also pose difficulty. None-the-less, several such switches have been built and demonstrated by using ferroelectric liquid crystal SLM""s. Another realization of this overall architecture employs fibers, 1-N fiber splitters and combiners and semiconductor optical amplifiers as amplifying switches that control each cross point. The resulting system may be compact since fiber splitters now replace bulky lenses allowing easy interfacing to fibers. Switching the semiconductor optical amplifiers very fast, may overcome reconfiguration speed limitations. The gain provided by the optical amplifiers may overcome broadcast loss, improving overall throughput efficiency. However, semiconductor optical amplifiers are expensive, hard to couple to fibers and are polarization sensitive. The cross bar switch based on semiconductor optical amplifiers may therefore be limited to small sizes ( less than 16).
One way to avoid broadcast loses may be to use light deflection switches instead of light modulation switches. One example of such a light deflection switch is an acoustooptic device. In an acoustooptic device, a traveling phase grating is created within a transparent crystal in response to applied RF signal to a piezoelectric transducer attached to one end of the crystal. The frequency of the grating and hence the deflection angle is controlled by the frequency of the RF drive signal. FIG. 8 (prior art) shows a schematic diagram of such a cross bar optical switch 800.
The diffraction efficiency of the grating as well as the coupling efficiency at the output end into a fiber together determines the throughput efficiency of this switch. The deflection efficiencies may be quite high and indeed acoustooptic beam deflectors are routinely used in image scanning applications. The traveling nature of the gratings in the acoustooptic device may pose problems. A way around this utilizes multi-channel acoustooptic devices with a separate channel and transducer for each input channel. This may make the whole system bulky and power consuming. Therefore its use in communication and computer interconnection switching is not widely accepted.
A schematic diagram of another free space optical cross bar design employing the basic architecture shown in FIG. 6 is shown in FIG. 9 (prior art). The main switching element is a micro mirror fabricated out of thin membranes using Micro Electro Mechanical (MEMs) technology. Micro-lenses 940 collimate optical signals (possibly provided by single mode fibers) into small area beams. These beams travel parallel to the MEMs substrate. The MEMs substrate contains an array of micro-mirrors 920 and 930 that may move into the path of incoming optical beams. When activated, the movement could be out of the plane where the mirrors pop up and lie in the plane when deactivated. Alternatively, the mirrors could slide into a position to intercept the beam when activated and slide out when deactivated. The micro-mirrors may reflect the input optical beams to the appropriate output port. In the current illustration, micro-mirrors 920 are activated and micro-mirrors 930 are deactivated creating the permutation pattern corresponding to: input 1902 to output C 956, input 2904 to output B 954, input 3906 to output D 958, and input 4908 to output A 952. This design is compact and readily interfaced to fiber. Also, this design is passive optical, meaning that the optical signals may be correctly switched regardless of the bandwidth or format. Reconfiguration speeds could be moderate, into the 100 kHz range. Scalability of this design may be an issue. A primary limitation may be cross talk between channels due to diffractive spreading of small area optical beams. If the beam diameter is increased to reduce diffractive spreading, the channel density may decrease and the propagation distance may increase, thereby increasing the diffractive spreading. The alignment of the lenses and optical fibers and output coupling into single mode optical fibers may also be an issue.
What is needed is an optical switching system that is compact; robust; efficient; easily scalable to greater than 100 optical channels; accepts a multitude of formats, bandwidths and wavelengths of optical signals; integrates control signals easily; is easy to manufacture; has low cross-talk; and easily interfaces to optical fibers.
One advantage of the invention is that it allows for the construction of a compact, robust and efficient optical switch.
Another advantage of this invention is that it provides for an optical switch that may be easily scalable to greater than 100 optical channels.
Yet a further advantage of this invention is that it accepts a multitude of formats, bandwidths, and wavelengths of optical signals.
Yet a further advantage of this invention is that it integrates control signals easily, is easy to manufacture, has low cross-talk; and is easy interface to optical fibers.
To achieve the foregoing and other advantages, in accordance with all of the invention as embodied and broadly described herein, an optical switch comprising a plurality of optical waveguide switches. Each of the plurality of optical waveguide switches comprise an optical waveguide. The optical waveguide includes a substrate having a hollow channel having a beginning and an end running through the substrate, a plate residing atop the hollow channel, an input aperture at the beginning of the hollow channel, and an output aperture at the end of the hollow channel. The optical waveguide also includes a plurality of micro-mechanical deflectable cantilevered beam mirrors formed in the plate and oriented along the optical waveguide. The micro-mechanical deflectable cantilevered beam mirrors have a deflected position where the micro-mechanical deflectable cantilevered beam mirrors are operably deflected out of the plane of the plate into the hollow channel for intercepting an optical signal and deflecting that optical signal out of the plane of the hollow waveguide, and a non-deflected position where the micro-mechanical deflectable cantilevered beam mirrors remain in the plane of the plate. A plurality of mirror apertures are operably formed when each of the micro-mechanical deflectable cantilevered beam mirrors are in their deflected position. The optical switch also comprises at least two layers, each of the layers comprising at least one of the optical waveguide switches; an optical waveguide switch stack comprising at least two layers stacked so that at least one of the plurality of mirror apertures from each of the optical waveguide switches on adjacent the layers are aligned; at least one input optical interface, each of the input optical interfaces attached to one of the input apertures for receiving an optical signal from at least one external source; and at least one output optical interface, each of the output optical interfaces attached to one of the output apertures for the optical signal to pass from the optical switch to at least one external receiver.
In yet a further aspect of the invention, an optical switch wherein the plate is a membrane.
In yet a further aspect of the invention, a cross connect switch where one of the layers is a first layer and where at least one of one of the optical waveguide switches on the first layer is a multitude of the optical waveguide switches aligned in parallel. Another layers is a second layer where at least one of one of the optical waveguide switches on the second layer is a multitude of the optical waveguide switches aligned in parallel. The first layer and the second layer are adjacent layers. The first layer and the second layer are aligned so that the optical waveguide switches on the first layer are perpendicular to the optical waveguide switches on the second layer.
In yet a further aspect of the invention, an optical switch wherein the micro-mechanical deflectable cantilevered beam mirrors are operably deflected in a predetermined pattern that is synchronous with a time modulated optical signal. The time modulated optical signal may be a display signal.
Additional objects, advantages and novel features of the invention will be set forth in part in the description which follows, and in part will become apparent to those skilled in the art upon examination of the following or may be learned by practice of the invention. The objects and advantages of the invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims.


An improved electromagnetic chuck which does not require a continuous direct current supply while being magnetized, including a main body defining a plurality of recesses and forming a cover, which includes a plurality of magnetically conductive portions and non-magnetically conductive portions alternately arranged, a plurality of magnetic units arranged within said plurality of recesses, and a magnetizing/demagnetizing circuit for magnetizing/demagnetizing said plurality of magnetic units, is provided. The magnetizing/demagnetizing circuit includes a magnetizing circuit, a demagnetizing circuit and an output circuit, by which a direct current is generated to magnetize the electromagnetic chuck, or a pair of positive and negative phase pulses with a gradually increased frequency is generated to quickly demagnetize the electromagnetic chuck.

1. Field of the Invention
The present invention relates to a magnetic device and, more particularly, to an improved electromagnetic chuck. The present invention discloses a high speed magnetizing/demagnetizing circuit used for the electromagnetic chuck.
2. Description of Related Art
In conventional machines such as electrical discharge machining (EDM) machines and grinding machines, a magnetic chuck is frequently used as a worktable, whereby a workpiece to be machined can be attracted upon the worktable by a magnetic force and then a machining operation is performed on the workpiece.
As known in the prior art, there are presently two types of magnetic chucks: permanent-magnetic chucks and electromagnetic chucks.
A permanent-magnetic chuck generally utilizes a plurality of permanent magnets. The magnetism of the permanent-magnetic chuck is determined according to the distance between the plurality of permanent magnets and the surface of the chuck as well as the arrangement of the plurality of permanent magnets.
The permanent-magnetic chuck utilizes magnets with a lower magnetic saturation point, so as to avoid resulting in significant residual magnetism on the workpiece and the surface of the chuck and thus making it difficult to remove the workpiece after the chuck is magnetically insulated. Therefore, permanent-magnetic chucks can merely be applied to machining applications with a low magnetic force demand.
An electromagnetic chuck applies the electromagnetic induction theory to generate magnetic force in order to attract a workpiece to be machined onto the surface of the chuck.
Conventionally, one drawback of the electromagnetic chuck is that it needs to be continuously provided with electric power so as to maintain its magnetic force. The magnetic units disposed within the electromagnetic chuck for generating the magnetic force gradually increase in temperature after an extended period of use. Such a rise in temperature will result in the deformation of the surface of the is electromagnetic chuck, that is, the flatness of the surface will become degraded.
In addition, the magnetic force generated by the electromagnetic chuck will dissipate when the coils of the magnetic units in the electromagnetic chuck are damaged, the power supply of the electromagnetic chuck is defective or the power is abruptly cut off, resulting in the workpiece to be machined being outwardly projected since the workpiece is still subject to the inertial force of the machining tool. Thus, it may damage the workpiece and injure the operator.
Furthermore, as the electromagnetic chuck needs to be firstly magnetized to attract a workpiece and then demagnetized after a workpiece has been machined, a magnetizing/demagnetizing circuit is usually employed. In conventional magnetizing/demagnetizing circuits, a direct current is generated to flow through the coils winding around a material to be magnetized in order to magnetize the material, and a gradually decreased voltage alternating between positive and negative via a relay is generated to apply to the coils winding around the magnetized material in order to demagnetize the material.
However, it is well known that the relay itself has several drawbacks such as operation with a time delay, large operational error and slow operational speed. The frequency of the alternating polarity of the applied voltage is low due to the slow operational speed of the relay, thus the time required to demagnetize the material is relatively prolonged (about 8 to 15 seconds).
Conventionally, the residual magnetism remaining within the magnetized material can not be minimized since the frequency of the alternating polarity provided by the relay is low. Thus, the conventional demagnetization performance is undesirable because the material may be incompletely demagnetized and the workpiece attracted onto the electromagnetic chuck may need to be separately demagnetized.

Electromagnetic chuck with magnetizing/demagnetizing circuit


A mirror unit includes: a mirror; a plurality of non-contact type actuators including movable elements and stators, and configured to change a shape of the mirror; a supporting plate to which the stators are fixed; and a structure configured to hold the mirror and the supporting plate. The movable elements are attached to a surface of the mirror that is opposite to an optical surface, and the structure holds the supporting plate via a kinematic mount.

Field of the Invention
The present invention relates to a deformable mirror unit capable of correcting the wavefront error and distortion of an optical system in an exposure apparatus, astronomical telescope, or the like, and an exposure apparatus.
Description of the Related Art
Recently, as a demand on the resolution of an exposure apparatus is becoming stricter, a demand for correcting aberration induced by exposure is also becoming stricter. To correct aberration induced by exposure, there has been proposed an arrangement using a deformable mirror.
Japanese Patent No. 4361269 discloses a mirror support structure in which an outer ring supports a reaction assembly to which a pneumatic actuator for deforming a mirror is attached, and an inner ring supporting the mirror. Japanese Patent Laid-Open No. 2004-64076 discloses a servo control mechanism including many actuators which support a deformable mirror at least three rigid positions, and displacement sensors located near them.
In Japanese Patent No. 4361269, the pneumatic actuator is mechanically coupled to the rear surface of the mirror via a rod, and thus excessively constrained with respect to the mirror. The mirror shape is readily affected by an assembly error. In the mirror support structure disclosed in Japanese Patent No. 4361269, the reaction force of the pneumatic actuator is transferred to the mirror via the reaction assembly, inner ring, and outer ring, and may affect the mirror shape.
Japanese Patent Laid-Open No. 2004-64076 has proposed a mirror unit with a displacement feedback driving control system including many actuators and displacement sensors located near them. The mirror unit with the displacement feedback driving control system measures the displacement of the mirror at or near each driving point, and controls the actuators so that the displacement coincides with a target displacement value in a given accuracy range. Hence, the mirror unit is free from the influence of a driving reaction force. However, this mirror unit has a complicated arrangement, requires many displacement sensors, and is expensive.


The present invention relates to a pneumatic rubber tire having an integral innerliner of a sulfur cured rubber composition. The innerliner rubber composition is comprised of at least one elastomer selected from bromobutyl rubber and chlorobutyl rubber which also contains a dispersion therein of corncob granules.

The inner surface of a pneumatic tire is typically comprised of an elastomeric composition designed to prevent or retard the permeation of air and moisture into the carcass from the tire's inner air chamber. It is often referred to as an innerliner. Rubbers, such as halobutyl and blends of butyl and halobutyl rubber, which are relatively impermeable to air are often used as a major proportion of the innerliners.
Accordingly, the air and moisture permeability resistance of the innerliner rubber composition is an important consideration.
The innerliner is normally prepared by conventional calendering or milling techniques to form a strip of uncured compounded rubber of appropriate width which is sometimes referred to as a gum strip. Typically, the gum strip is the first element of the tire applied to a tire building drum, over and around which the remainder of the tire is built. When the tire is cured, the innerliner becomes an integral, co-cured, part of the tire. Tire innerliners and their methods of preparation are well known to those having skill in such art.
There remains an ongoing desire to provide enhanced or suitable variations of butyl rubber-based tire innerliners without significantly affecting the air and moisture permeability resistance of the innerliner rubber composition.
Halobutyl and butyl rubbers are usually one of the most expensive elastomers used in a tire. Given the competitive tire market and the continued need to lower the cost of manufacturing tires, there exists a desire to decrease the cost of innerliners which perform such an important function in the performance of a tire.
In the description of the invention, the term "phr" relates to parts by weight of a particular ingredient per 100 parts by weight of rubber contained in a rubber composition. The terms "rubber" and "elastomer" are used interchangeably unless otherwise indicated, the terms "cure" and vulcanize" may be used interchangeably unless otherwise indicated and the terms "rubber composition" and "rubber compound" may be used interchangeably unless otherwise indicated. The term "corncob granules" is used herein to refer to corncob granules which are obtained from the woody ring surrounding the central core, or pith, of the corncob. The corncob granules are manufactured by drying the woody ring portion, or fraction, of the corncob followed by grinding to produce the granules which are air cleaned and separated into various sizes by mesh screening. Such corncob granules are manufactured by The Andersons, Inc. and sold as Grit-O' cobs® (corncob granules, for example as 60 Grit-O' cobs®. For further corncob granule discussion, see "Use of Fine-R-Cobs as a Filler For Plastics", by D. B. Vanderhooven and J. G. Moore, reprinted from the Internal Wire and Cable Symposium 1982.

Pneumatic tire having an innerliner comprised of butyl rubber and dispersion of corncob granules


In a computer I/O system including a plurality of link-level facilities and a dynamic switch having a plurality of ports, each link-level facility being attached to an individual one of the ports, a mechanism and method for assigning a unique link level address to each of the link-level facilities. As each of the link-level facilities comes on line, it sends an acquire link address (ALA) frame and waits for a response (ACK) frame. The ALA frame may be addressed to a general to-whom-it-may-concern address and have a source address of who-am-I. Only a dynamic switch normally assigns link addresses. When receiving an ALA frame, the dynamic switch returns an ACK frame having a unique link address assigned to the sender of the ALA frame. Provision is made for determining if there is a dynamic switch present, or, if the link-level facilities are connected together by a static connection through the dynamic switch, for the link-level facility of a channel to assign the unique link addresses.

The present invention relates to assigning addresses to devices in a computer input/output (I/O) system, and more particularly relates to I/O devices automatically acquiring addresses in an I/O system.
The need for assigning unique addresses to I/O devices in a computer system is well known. Rosenberg, "Program Controlled I/O Address Assignment", IBM Technical Disclosure Bulletin, Vol. 16, No. 1, June 1973, pages 67-68, discloses dynamically assigning addresses to control units wherein an I/O controller places a reset address on an I/O interface and energizes an I/O Op line. A device attached to the I/O controller responds to the I/O Op line, and the I/O interface supplies the I/O controller with a program assigned address, which is transferred by the controller to the device.
Mitchell, Jr., "Input/Output Device Address Recognition Mechanism", IBM Technical Disclosure Bulletin, Vol. 20, No. 7, December, 1977, pages 2652-2653, discloses an I/O device address recognition mechanism wherein a full device address assignment is initially made or changed dynamically by way of a utility program.
Arndt, "Satellite Station Address Assignment Method", IBM Technical Disclosure Bulletin, Vol. 22, No. 5, October, 1979, pages 2063-2064, discloses a method wherein a satellite station assigns itself a special address for answering a poll to this address by a master station. After receiving a response to the poll, the master station selects the next available address from a list and issues a command to the satellite address, assigning the selected address to the satellite.
Hill et al, "Dynamic Device Address Assignment Mechanism", IBM Technical Disclosure Bulletin, Vol. 23, No. 8, January, 1981, pages 3564-3565, discloses an assignment mechanism wherein a host processor assigns device addresses to device control units by a SET DEVICE ADDRESS command. This command sets the desired address into a device address register in the first (or next) device control unit.
Janson et al, "Dynamic Address Allocation in a Local Area Network", IBM Technical Disclosure Bulletin, Vol. 25, No. 12, May, 1983, pages 6343-6345, discloses a technique for dynamically assigning unique stations or their individual functions in a local area network wherein the general clock is used to make the addresses unique.
U.S. Pat. No. 4,155,117 issued May 15, 1979 to Mitchell, Jr. et al for "Synchronizing Channel-to-Channel Adapter" discloses a channel-to-channel adapter capable of enabling communication between more than two data processors wherein device addresses are selected in advance and reserved for communication with the disclosed channel-to-channel adapter.
U.S. Pat. No. 4,373,181 issued Feb. 8, 1983 to Chisholm et al for "Dynamic Device Address Assignment Mechanism for a Data Processing System" discloses a peripheral device address assignment mechanism in which a unique I/O command on the processor I/O bus loads the device address into a loadable device address register is each peripheral device control unit.
U.S. Pat. No. 4,608,562 issued Aug. 26, 1986 to Minor et al for "Address Personalization for a Remotely Attached Device" discloses a data transmission system wherein the polarization of a serially transmitted test signal and a locally generated control signal are used to provide unique addresses for identical devices connected to a transmitting unit.
U.S. Pat. No. 4,638,313 issued Jan. 20, 1987 to Sherwood, Jr. et al for "Addressing for a Multipoint Communication System for Patient Monitoring" discloses a method for dynamically assigning addresses to new modules as they are coupled to a communication system with a synchronous data link control bus controlled by a primary station wherein the primary station sends the module a packet which assigns the module with the next available address.
U.S. Pat. No. 4,800,384 issued Jan. 24, 1989 to Snijders for "Arrangement for Identifying Peripheral Apparatus Such as Workstations, Printers and Such Like, Which Can Optionally Be Connected in Geographically Different Locations to a Communication Network by Means of Local Coupling Units" discloses a module coupling unit which functions as an interface between a communication unit or peripheral apparatus and a communications network and which includes a code word signal generator for generating a unique address code which is stored in the coupling unit and which can be read and transferred to a diagnostic module for determining the geographical address of a communications unit in which a disturbance has occurred.
U.S. Pat. No. 4,922,410 issued May 1, 1990 to Morikawa et al for "Input/Output System Capable of Allotting Addresses to a Plurality of Input/Output Devices" discloses an input/output processing system including a plurality of channels connected to each of a plurality of input/output control devices and a memory unit for storing information representing the address of each of the control devices in association with the identification number of the channel connected to the control devices. The channel for data transfer is selected upon evoking a request from a central processing unit whereupon the information representing the address of the controller device is read out from the memory unit and the address of the control device is generated on the basis of the information thus read out.

Acquiring addresses in an input/output system


A multichip module includes: a) a multichip module substrate; b) a first chip, the first chip having opposed base and bonding faces, the base face being adhered to the multichip module substrate, the first chip bonding face including a central area and a plurality of bonding pads peripheral to the central area; c) a second chip, the second chip having opposed base and bonding faces, the second chip bonding face including a central area and a plurality of peripheral bonding pads; d) a first/second adhesive layer interposed between and connecting the first chip bonding face and the second chip base face, the first/second adhesive layer having a thickness and a perimeter, the perimeter being positioned within the central area inside of the peripheral bonding pads; e) a plurality of first loop bonding wires bonded to and between the respective first chip bonding pads and the multichip module substrate, the respective first bonding wires having outwardly projecting loops of a defined loop height, the thickness of the adhesive layer being greater than the loop height to displace the second chip base face in a non-contacting relationship above and with respect to the first wires; and f) a plurality of second loop bonding wires bonded to and between the respective second chip bonding pads and the multichip module substrate.

Considerable advancement has occurred in the last fifty years in electronic development and packaging. Integrated circuit density has and continues to increase at a significant rate. However by the 1980's, the increase in density in integrated circuitry was not being matched with a corresponding increase in density of the interconnecting circuitry external of circuitry formed within a chip. Many new packaging technologies have emerged. One specific technology is referred to as "multichip module" technology. This invention concerns the specific art area of multichip modules.
In many cases, multichip modules can be fabricated faster and more cheaply than by designing new substrate integrated circuitry. Multichip module technology is advantageous because of the density increase. With increased density comes equivalent improvements in signal propagation speed and overall device weight unmatched by other means. Current multichip module construction typically consists of a printed circuit board substrate to which a series of integrated circuit components are directly adhered.
There are further a number of distinct art areas associated with how a substrate adhered circuit of a multichip module is electrically externally connected to circuitry on the substrate. These art areas include wire bonding, tape automated bonding (TAB), flip-TAB and flip-chip. This invention is specific to the distinct art area of wire bonding associated with multichip modules.

Multichip module having a stacked chip arrangement


An articulating marsh buggy or vehicle in the form of an articulated amphibious vehicle incorporating a front and rear drive unit which are pivotally connected for relative angular movement about a generally vertical axis and oscillatable about a generally longitudinal axis. Each of the units includes a pair of pivotal floatable pontoons with each pontoon including a drive chain on which elongated cleats are transversely mounted. The drive chains are driven by independent hydraulic motors to enable the vehicle to move over various terrains and be propelled in marshy areas, bayous or water bodies by cleats on the driven chains on the pontoons.

1. Field of the Invention
The present invention relates to an articulating marsh buggy in the form of an amphibious vehicle incorporating forward and rear drive units which are pivotally connected for relative angular movement about a vertical axis and oscillatable about a longitudinal axis. Each of the drive units includes a pair of pivotal, floatable pontoons with each pontoon including a drive chain on which cleats are mounted. The drive chains are driven by independent motors to enable the vehicle to move over various ground terrains and be propelled in marshy areas, bayous or water bodies by cleats on the driven chains on the pontoons.
2. Description of the Prior Art
Amphibious marsh buggies or vehicles were first developed about 50 years ago. One use of these vehicles was to support oil and gas exploration. The vehicles originally developed for this task were equipped with four large wheels and two engines. These wheels were designed with deep lugged cleats for traction and built of light weight steel for durability and buoyancy. The drive engines were installed on the right and left sides of the vehicles' main frame. Each engine powered the two wheels on their respective sides. Steering or turning was achieved by increasing and/or decreasing engine speeds which in turn controlled wheel revolutions and made turning possible. For example, if the driver was required to turn the vehicle to the right, this was accomplished by increasing engine and wheel RPMs on the left side and vice versa to turn left.
A short time after these vehicles were put into service it was determined that their environmental impact was so destructive that they were banned. This led to the development of a second generation vehicle which incorporated the use of pontoons and a track drive system. Each unit was configured with two longitudinal side pontoons which provided the required buoyancy and a continuous drive track around each pontoon provided drive power. Channel type cleats were provided on the drive tracks for traction, with both tracks being driven by a single engine. This track drive system also incorporated a unique braking system to control steering. This type of steering system requires the driver to lock or stop the track movement on one side while allowing the other side to continue pulling. This concept is similar to the steering system used on bulldozers and cranes.
As with all vehicles equipped with this type steering system, when turning right for instance, it is necessary to lock or stop track movement on the right side while pulling with the left side. Therefore, in order to turn it is necessary to develop sufficient pulling force and traction on one side to overcome not only the weight of the unit, but also the drag resistance of the locked tracks on the opposite side. When this turning or "skidding" method is used in ecologically sensitive areas, where tender vegetation and loose root structure exist, the results are disastrous. These units, designed and built in the 1960's, have undergone little improvement to date and are still the primary means of support utilized by the oil and gas industry.
The following U.S. patents may be pertinent to the vehicle of the present invention:
______________________________________ 3,435,908 3,789,942 4,174,757 3,443,654 3,937,289 4,645,023 3,451,494 4,072,203 4,966,242 ______________________________________
However, the above patents do not disclose the structural arrangement and operational characteristics of the present invention.


A curative composition comprising a cation and an anion of the formula Anq−Qpm+, wherein m, n, p, and q are positive integers, wherein m*p=n*q, wherein Qm+ is an organo onium, and Aq− is an anion, provided that at least one Aq− is selected from the formula:

Fluoroelastomers are cured or crosslinked and generally are tolerant to high temperatures and harsh chemical environments. They are particularly useful as seals, gaskets, and molded parts in systems that are exposed to elevated temperatures and/or corrosive materials. For sealing applications that require resistance to the most extreme conditions, perfluorinated elastomers are used. Such parts are used in applications such as automotive, chemical processing, semiconductor, aerospace, and petroleum industries, among others.
Fluoroelastomers often include a cure-site component to facilitate cure in the presence of a curative or catalyst. One class of useful cure-site components used in perfluoroelastomers includes nitrile group-containing monomers, for which organotin catalysts have been used as curing components. However, such catalysts can leave undesirable extractable metal residues in the cured product and are undesirable for environmental reasons. Ammonia-generating compounds have also been used as a cure system component in fluoroelastomers, but these cure systems lack the desired level of rheology control during processing. In addition, most known fluoroelastomers are cured into colored or opaque materials. A few fluoroelastomers or perfluoroelastomers have been described as colorless and/or transparent, yet can be cloudy or milky in appearance, and have rather high compression set when made into seals, even when measured at relatively low temperatures (up to 200° C.).

Abstract: wherein each R independently is H, halo, alkyl, aryl, aralkyl, or cycloalkyl, and which also may be halogenated, fluorinated, or perfluorinated, wherein two or more of R and R′ groups may together form a ring, wherein each R group independently may contain one or more heteroatom(s), wherein R′ can be the same as R, with the proviso that R′ cannot be halo. Also provided are a fluoropolymer composition including this curative, a method of making a fluoropolymer, and fluoropolymer articles containing curable or cured fluoropolymer compositions.


There is provided a method, comprising: providing a training dataset including, medical images and corresponding text based reports, and concurrently training a natural language processing (NLP) machine learning (ML) model for generating a NLP category for a target text based report and a visual ML model for generating a visual finding for a target image, by: training the NLP ML model using the text based reports of the training dataset and a ground truth comprising the visual finding generated by the visual ML model in response to an input of the images corresponding to the text based reports of the training dataset, and training the visual ML model using the images of the training dataset and a ground truth comprising the NLP category generated by the NLP ML model in response to an input of the text based reports corresponding to the images of the training dataset.

The present invention, in some embodiments thereof, relates to machine learning (ML) models and, more specifically, but not exclusively, to training an ML model using a training dataset with no labels or minimal labels.
Labelling data for training a ML models affects performance of the ML model. However, standard labelling processes are manual, which are slow, expensive and prone to error at best, or at worst, not available. Manual labeling of medical images is performed by a trained professional that looks at the image, and assigns a ground truth label of whether a certain visual finding is present in the image or not, for example, whether a CT image slice of a brain depicts bleeding in the brain or not.

Cross modality training of machine learning models


A manufacturing apparatus of a porous glass base material is provided. The manufacturing apparatus includes a burner repeatedly moving back and forthreciprocating in a direction along a longitudinal direction of an axis-rotating base member glass rod, where the burner ejects and deposits glass particles onto the base member glass rod, and an exhaust hood positioned above a porous glass soot formed by the deposition of the glass particles, where the exhaust hood repeatedly moves back and forth reciprocates in a same direction as the burner in synchronization with the burner. Here, the exhaust hood surrounds a portion of the porous glass soot corresponding to an angle θ of 100° or more with respect to an axial centera central axis of the porous glass soot. To be more specific, the angle θ may be preferably 180° or more.

FIG. 1 illustrates a typical manufacturing apparatus of a porous glass base material. In such a manufacturing apparatus, a base member glass rod 1 is axis-rotatably disposed, and a burner 2 is provided in a lower section. The burner 2 repeatedly moves back and forth reciprocates along the longitudinal direction of the base member glass rod 1, and ejects glass particles produced by flame hydrolysis onto the lateral surface of the base member glass rod 1. The glass particles are deposited sequentially in the longitudinal direction, thereby forming a porous glass soot 3.
Above the porous glass soot 3 are provided an exhaust hood 4 and an exhaust pipe 5 so as to oppose the burner 2. The exhaust hood 4 and exhaust pipe 5 are used to emit a combustion waste gas and unattached glass particles outside. Here, if the exhaust gas flow is disturbed within the apparatus some problems may occur. For example, the soot may break while the deposition is being performed, or a bubble may be created as a result of vitrification into a transparent glass because non-deposited glass particles are later deposited.
To deal with these problems, Patent Document 1 proposes the following method. The porous glass soot 3 is housed within a tubular member 6, and the exhaust pipe 5 is provided in substantially the middle of the tubular member 6. This enables the exhaust gas to flow in a direction along the longitudinal direction of the porous glass soot 3, thereby reducing bubbles. Here, the reference numeral 7 indicates a gas inlet (see FIG. 2).
[Patent Document 1] Unexamined Patent Application Publication No. S59-190232

Manufacturing apparatus of porous glass base material and glass base material for optical fiber


The present invention relates to a method and apparatus for transmitting channel state information in a cooperative multipoint communication system. A method for a terminal transmitting the channel state information (CSI) to multiple base stations according to one embodiment includes receiving a first piece of CSI setting information with respect to reporting of CSI including at least one of a rank indicator (RI), a precoding matrix indicator (PMI), and a channel quality indicator (CQI), with respect to a first base station; receiving a second piece of CSI setting information with respect to reporting of CSI including at least one of an RI, a PMI, and a CQI, with respect to a second base station; and transmitting the CSI with respect to the first base station and the second base station on the basis of the CSI setting information on the first and second base stations.

Multi-Input Multi-Output (MIMO) technology is to improve efficiency in data transmission and reception by using multiple transmitting antennas and multiple receiving antennas instead of a single transmitting antenna and a single receiving antenna. If a single antenna is used, a receiving side receives data through a single antenna path. However, if multiple antennas are used, the receiving side receives data through various paths. Accordingly, speed and amount in data transmission may be increased, and coverage may be increased.
A single-cell MIMO operation may be divided into a single user-MIMO (SU-MIMO) scheme, in which one user equipment receives a downlink signal from one cell, and a multi user-MIMO (MU-MIMO) scheme, in which two or more user equipments receive a downlink signal from one cell.
In the meantime, a coordinated multi-point (CoMP) system for improving throughput of a user located at the cell edge by applying improved MIMO transmission under the multi-cell environment has been actively studied. If the CoMP system is applied, inter-cell interference may be reduced under the multi-cell environment, and system throughput may be improved.

Method and apparatus for transreceiving channel state information in cooperative multipoint communication system


An adaptive method and apparatus for regulating connection admission of traffic for networks, which includes a limiter that limits a volume of traffic admitted to a network through a connection admission control (CAC) procedure; and basing the connection admission control procedure at least in part on a pure measurement CAC that is solely based on measurements of actual traffic levels on the network. The connection admission control is based both on the pure measurement-based CAC and on a pure mathematical-based CAC that is solely dependent on user-supplied traffic parameters, thereby combining both types of the CAC to form a hybrid admission criterion. Where the network offers different services, managing link resources for CAC is effected by regulating the CAC procedure based on capacities assigned to service bandwidth pools that are defined for the different services offered by the network. The CAC procedure may take place on a virtual network (VN) environment.

Packet networks that offer their users certain level of performance usually require a set of traffic management capabilities. Among this set of capabilities, admission control plays a key role in limiting the volume of the traffic admitted to the network hence facilitate the support of QoS (Quality of Service) by the network.
The admission control function is often performed based on some expectation of the user""s traffic profile. This profile is supplied to the network at the set up phase in the form of a limited set of traffic characteristics such as peak rate, sustained rate, and burst size. The values assigned to this set of traffic characteristic are often based on the user""s best guess or some default values supplied by the manufacturers or the service providers or both. Consequently these values may bear little resemblance to the actual user activity and traffic pattern. Furthermore, the user is seldom active all the time, sending continuous traffic stream at the above rates, which causes a further diversion between the actual and the nominal traffic values.
An admission control procedure that is solely based on the supplied traffic parameters is usually referred to as mathematical CAC (connection admission control). A mathematical CAC usually leads to a network that is either over-utilized, hence is not able to guarantee the QoS parameters to its users, or a network that is under-utilized, hence not able to maximize its revenue. In most cases the latter case would prevail because of the tendency of the user to assign conservative values to their traffic parameters. Service providers usually compensate for the over-allocation of resources by introducing an overbooking factor that allows better utilization of their network resources.
It is therefore desirable to implement CAC procedures that take into account the current network status based on actual measurements. Since CAC procedures are different for the different services, it is also necessary to dynamically partition the network resources among the different services and virtual networks (customer networks running on a common service provider infrastructure) supported by the network.
The text of the ensuing description makes reference to the following documents by identifying the numeral associated with the corresponding reference as found to the left hand side below.
[1] R. Braden et. Al., xe2x80x9cResource Reservation Protocol (RSVP)xe2x80x94Version 1 Functional Specificationsxe2x80x9d, RFC 2205, September 1997.
[2] The ATM Forumn, User Network Interface (UNI) Signaling Specifications, February 1996.
[3] B. Jamoussi et. al., xe2x80x9cSystem and Method for a Connection Admission Control Scheme in a Multi-Service ATM Networksxe2x80x9d, Patent application, September 1997.
[4] B. Jamoussi, et. al., xe2x80x9cPerformance Evaluation of Connection Admission Control Techniques in ATM Networksxe2x80x9d, IEEE Globecom Conference 1996.
[5] P. White and J. Crowcroft, xe2x80x9cThe Integrated Services in the Internet: State of the ARTxe2x80x9d, IEEE Proceedings, December 1997.
[6] ATM Forum, P-NNI Specification, 1995.
The CAC function plays an essential role for networks supporting some level of service guarantee for its customers. The first step of the CAC procedure is the reception of the connection establishment message containing the necessary information (traffic and QoS parameters) for the network to execute the mathematical CAC. The outcome of this step is the computation of the EBR (equivalent bit rate).
The EBR is combined in a certain fashion with the network measurements in order to formulate the admission criterion, taking into account the bandwidth assigned to the particular service class. The development of an EBR algorithm requires the mapping of the traffic parameters to an adequate statistical model and assumptions regarding the architecture of the transmission scheduler of the node and the size of the available buffer.
For the CBR (constant bit rate) and premium services where the traffic peak rate is of paramount importance, the traffic parameter of interest to the EBR algorithm is usually the traffic peak rate. For VBR (variable bit rate) services, the traffic parameters of interest are the peak rate, the average rate, and the burst size.
For CBR-like services, the easiest way to compute the EBR is to set its value equal to the connection""s peak rate. This is particularly true if the node is equipped with sufficient buffer and the cell delay variation tolerance of the input scheme is small. More elaborate schemes are also possible [3].
For VBR-like service, one EBR algorithm that has seen wide use is the EGH (extended Gibbens-Hunt) algorithm [4]. EGH algorithm assumes a FIFO (first-in-first-out) scheduler for the node and an aggregate buffer of size B. The EGH algorithm maps the input traffic parameters to a two-state Markov-fluid model where a source alternates between active and idle states with exponentially distributed periods with parameters xcex1 and xcex2 respectively. While being active, traffic is assumed to be generated with rate xcex units/s. With those assumptions, the EBR computed using the EGH algorithm for ATM-based networks is given by   EBR  =                    -                  [                      α            +            β            -                          γ                                            xe2x80x83                                          λ                                ]                    +                                                  [                              α                +                β                -                                  γ                                                        xe2x80x83                                                      λ                                            ]                        2                    +                      4                                      xe2x80x83                                    γ                                      xe2x80x83                                    β                                      xe2x80x83                                    λ                                      2                    xe2x80x83                  γ
Where xcex3_=_xe2x88x92log(CLR)/B*Pr[W greater than 0], and CLR is the QoS parameter in terms of cell loss rate, B is the buffer size available at the node, and P[W greater than 0] is the probability that the combined rate of the active sources exceeds the link capacity (probability of a non-empty queue).
Obviously the EGH algorithm is a loss-based algorithm in the sense that it is only applicable when the loss rate is the QoS parameter of interest. In many cases delay is the parameter of interest and the CAC procedure should be performed in a way to guarantee an upper bound on the delay experienced by a flow. An example of such service is the guaranteed service proposed for the Internet [5]. For the delay-dominated services, the EBR could be computed from [5]  Delay  =                              (                      b            -            M                    )                xc3x97                  (                      p            -            EBR                    )                            EBR                          xe2x80x83                                  (                      p            -            r                    )                      +                  M        +                  C          tot                    EBR        +          D      tot
where r and b are the rate and the depth of a token bucket characterizing the envelope of the flow, M is the maximum packet size, and Ctot and Dtot are error terms related to the scheduler and the finite packet sizes that are being dealt with.
An essential requirement of a signaling protocol used is its ability to provide, in addition to other information, the capability to carry the traffic and the QoS parameters requested by the user.
Instances of signaling protocols that satisfy those requirements are the RSVP protocol [1] for the Intemet (IP-based networks) and UNI (user-network interface) and P-NNI signaling [2] for ATM (asynchronous transfer mode) networks. In RSVP signaling, traffic parameters are carried in the T_spec field of the protocol and the results of the reservation procedures are carried in the R_spec field of the protocol. In UNI and P-NNI signaling, both the traffic and QoS parameters in terms of loss ratio and delay bounds are carried as IE (information elements) of the signaling protocol.
An example of routing protocols is the P-NNI (private network-to-network interface) of the ATM Forum [6] where the source node gathers the link state information advertised by the routing protocol to perform what is referred to as GCAC (generic CAC). The main function of the GCAC is to verify that an end-to-end path with sufficient resources will likely exist before performing the actual CAC on a link-by-link basis.
This invention describes a method and procedures of a hybrid CAC function that combines both the mathematical and the measurement aspects of the traffic. CAC functions based on some form of measurements is usually referred to as measurement-based CAC. Measurement-based CAC allows better utilization of network resources since the admission decision is based on knowledge of the network""s state.
One major advantage of the proposed hybrid approach that combines mathematical-based and measurement-based CAC is its ability to guard against those ID periods of time where the activity on the network in terms of its utilization is low. During those periods a large number of flows could be admitted to the network and remain idle. A congestion state is inevitable when those connections suddenly turn active. This situation could happen when users sign on at 8:00 a.m., but generate traffic at the peak rate two hours later, or for permanent virtual connections which typically generate no traffic at the time of their activation.
This invention also proposes a novel method for the resource assignment to the different services the network offers. This proposed resource assignment is made possible by the introduction of the bandwidth pools. Pools are defined for the different services and the admission decision is regulated based on the capacity assigned to each service pool. The introduction of the bandwidth pools makes the proposed CAC scheme independent of the actual transmission scheduler of the node.
This invention also addresses the issue of sharing the resource of a virtual networks supported on top of the physical network. This invention introduces a CAC methodology for the support of virtual private networks.
One aspect of the invention reside in an adaptive method and apparatus for regulating connection admission of traffic for networks, which includes a limiter that limits a volume of traffic admitted to a network through a connection admission control (CAC) procedure; and basing the connection admission control procedure at least in part on a pure measurement CAC that is solely based on measurements of actual traffic levels on the network. The connection admission control is based both on the pure measurement-based CAC and on a pure mathematical-based CAC that is solely dependent on user-supplied traffic parameters, thereby combining both types of the CAC to form a hybrid admission criterion. Where the network offers different services, managing link resources for CAC is effected by regulating the CAC procedure based on capacities assigned to service bandwidth pools that are defined for the different services offered by the network. The CAC procedure may take place on a virtual network (VN) environment.

Adaptive connection admission control scheme for packet networks