Abstract: A digital audio broadcasting system incorporates a perceptual audio coder that encodes a digital audio signal for broadcast. A "source label" is provided by controlling the perceptual audio coder in such a way that the number of coefficient samples, n, used in each transmission frame represents information about the source. For example, if the value of n is odd, then a binary "1" is transmitted, but if the value of n is even, then a binary "0" is transmitted. As a result, a low-bit rate "source label" is transmitted over a number of frames. In a receiver, the source of the digital audio signal is identified by simply monitoring the value of n over the number of frames. More importantly, the value of n in each frame is required by a corresponding perceptual audio decoder, in the receiver, to correctly recover the digital audio signal.

Abstract: A splice housing assembly for joining together at least two fiber optic cables. The splice housing assembly has a housing adapted to create a water impervious seal around both a splicing chamber and at least two fiber optic cables that lead into the splicing chamber through the housing. Within the splicing chamber, the various fiber optic cables are joined together via a grounding block or by a direct optical splice. The housing provides structural integrity, electrical insulation and water tightness to the splice, yet the housing can be selectively opened and closed. As a result, any splice can be made and tested, then repaired or adjusted before the housing is permanently sealed with an encapsulation compound.

Abstract: A communication network system provides a network presence for an entity, the network presence being identified by handle information relating to the entity, the handle information being unrelated to a physical endpoint. Attributes of the entity are associated with the handle information. The handle is a source of vendor services to the entity, and may be a source of services from the entity to others.

Abstract: A method for retrieving video data which has been striped across a plurality of disks using a coarse-grained striping technique. Specifically, and in accordance with an illustrative embodiment of the present invention, the method comprises scheduling the retrieval of a video in response to an incoming request and based on the availability of bandwidth on the disks, and then rescheduling the retrieval of that video to occur at an earlier time, the rescheduling based on a change (i.e., an increase) in the availability of bandwidth on the disks which results from the retrieval of another video being completed. The scheduling and rescheduling may, for example, comprise assigning a disk to the video, where the method further comprises incrementing the disk assigned to the video as each round occurs and beginning the retrieval of the given video when the disk assigned to it is the disk on which the data for the given video begins.

Abstract: An independent transport layer is used as an error correction mechanism in a method employing perceptual audio coding. The transport layer is characterized by the addition of information, via a transport header, to each of a succession of blocks of encoded program material which is independent of the information within its respective block of encoded program material. The transport header comprises information on the structure of the block. Thus, the transport header is easily separated from the digital representation of the program material and is independent of the content of the digital representation thereby providing for changing of the content of the digital representation without changing the transport layer.

Abstract: Apparatus and methods for communicating using protocols. The apparatus and methods employ protocol descriptions written in a device-independent protocol description language. A protocol is executed by employing a protocol description language interpreter to interpret the protocol description. Communication using any protocol for which there is a protocol description may be done by means of a general protocol. The general protocol includes a first general protocol message which includes a protocol description for a specific protocol. The protocol apparatus which receives the first protocol message employs a protocol description language interpreter to interpret the included protocol description and thereby to execute the specific protocol.

Abstract: Apparatus for discovering information about the source code of a computer program. The apparatus includes a translator for translating a parse tree produced for the program's language in a specific programming environment into an independent parse tree and an analyzer for analyzing the independent parse tree to discover the information. The translator is generated by a translator generator from a specification for the language and the programming environment and the analyzer is generated by an analyzer generator from a specification of the information to be discovered. The specification of the information to be discovered may specify only methods of analysis which can be completed in polynomial time. Methods of using the apparatus are also disclosed.

Abstract: The present invention is directed to a lithographic process for device fabrication. In lithographic processes for device fabrication, exposing radiation is used to delineate the image of a pattern into a layer of an energy sensitive resist material formed over a substrate. The pattern is then developed and the pattern is introduced into the underlying substrate. In the present invention, the substrate, typically a silicon wafer, is placed in a tool which utilizes electron beams as the exposing radiation. The silicon wafer has topographic alignment marks formed thereon. The alignment marks are used to orient the wafer in the tool accurately. The placement of the wafer in the tool is monitored by observing the intensity of the electron signal backscattered from the surface of the substrate.

Abstract: A relatively simple, low cost apparatus detects the presence and location of faults in an optical transmission system. It is particularly applicable to underwater optical transmission systems. The optical transmission system contains at least one optical fiber pair extending between two terminals. Optical amplifier based repeaters are located at predetermined positions along fibers. Each repeater has a simple high-loss optical loopback circuit which is used to provide fault identification and location. The loopback circuit couples a portion of the optical signal travelling from a transmitting station through one of the fibers, attenuates that portion of the optical signal, and adds the attenuated signal to the optical signal in the other fiber for return to the transmitting station. Fault location is accomplished by launching a supervisory signal into the fiber from one of the terminals.

Abstract: An image classifier, which performs character recognition, receives input images and assigns each input image to one of a plurality of image classes. The image classifier includes plural class distribution maps, each based on a plurality of features evaluated on training images, and each representing those feature values that occur at least once among the training images belonging to the corresponding class. The image classifier further includes means for constructing a test map by evaluating the plurality of features on the input image. The image classifier further includes means for comparing the test map to the class distribution maps in order to identify which one of the class distribution maps has the least distance to the test map. At least one of the features is defined according to a rule that relates to the shapes of images of at least one image class.

Abstract: A method and apparatus for providing high-speed data compressing without sacrificing the quality of data reconstruction. Each input vector or block of original data is expressed as a combination of a codebook index and an error differential, or as a compressed version of the original block of data, depending on whether the total number of bits needed to express the input vector as a combination of a codebook index and an error differential is less than the total bits needed to send the compressed version of the original block of data. In one embodiment, the flexibility to express video data in a compressed format or as a combination of a codebook index plus an error differential is provided through a video system employing a codebook, a scalar quantizer, and an entropy coder.

Abstract: A telephone central office switch (103) provides Centrex features, including intercom dialing, on central-office-to-PBX (133, 134) trunks (123, 124) by using the 4-wire subscriber feature of the Lucent Technologies 5ESS.RTM. switch to administer trunk ports (113-114) that serve the central-office-to-PBX trunks as 4-wire telephone lines and then further administering those trunk ports for Centrex features. Those trunk ports, and optionally also some line ports (115-116), may be administratively assigned the private network numbering plan of respective PBXs so as to enable intercom dialing among those trunk ports, and between those trunk ports and the optional line ports.

Abstract: A system for automatically classification of human fingerprints. An unidentified fingerprint is processed to produce a direction map. The direction map is processed to generate a course direction map. The coarse direction map is input to a locally connected, highly constrained feed-forward neural network. The neural network has a highly structured architecture well-suited to exploit the rotational symmetries and asymmetries of human fingerprints. The neural network classifies the unidentified fingerprint into one of five classifications: Whorl, Double Loop, Left Loop, Right Arch and Arch.

Abstract: A method for making a metal-to-metal capacitor for an integrated circuit includes forming a layer of titanium/titanium nitride on a polysilicon which has been patterned with interlevel dielectrics. A capacitor dielectric is then deposited, followed by patterning with photoresist to delineate the capacitor, etching to remove extraneous dielectric, deposition of aluminum, further patterning and etching to define the capacitor and access area, and removal of photoresist.

Abstract: An apparatus for modulating an optical signal and a method for fabricating such an apparatus, are disclosed. The apparatus, which may be formed on a semiconductor wafer or chip, consists of a membrane that is supported over a substrate by flexible support arms. An air gap is defined between the membrane and substrate. The membrane thickness and refractive index are chosen so that the reflectivities of the membrane and substrate are not 180.degree. out of phase. Under the action of bias, the membrane moves vertically from a first position to a second position relative to the substrate, changing the air gap. The reflectivity of the modulator changes as the air gap changes. Membrane thickness and the air gap are suitably selected to achieve zero overall modulator reflectivity in one of the two membrane positions. Equations define acceptable values for the thickness of the membrane thickness and the air gap. The membrane and air gap are formed by various etching and photolithographic methods.

Abstract: Apparatus for stripping a thin color-encoded plastic coating from an optical fiber comprises an elongated rail and clamps for fixedly mounting a fiber spaced above and parallel to the rail. A chuck having radially convergible jaws is mounted on the rail for movement therealong, and a lifting mechanism is provided for lifting the chuck towards the clamped fiber for disposing the fiber within the chuck and coaxial therewith. A stripping process comprises converging the jaws into a slightly compressive engagement with the fiber outer surface and sliding the compressively engaged chuck back and forth along the rail one or more times for abrasion removal of the fiber plastic coating.

Abstract: A high quality interface between a GaAs-based semiconductor and a Ga.sub.2 O.sub.3 dielectric an be formed if the semiconductor surface is caused to have less than 1% of a monolayer impurity coverage at completion of the first monolayer of the Ga.sub.2 O.sub.3 on the surface. This is achieved, for instance, by preparing the surface of a GaAs wafer under UHV conditions in a first growth chamber, transferring the wafer through a transfer module under UHV to a second growth chamber that is also under UHV, and growing the dielectric by evaporation of Ga.sub.2 O.sub.3 from a solid source, the process carried out such that the integrated impurity exposure of the surface is at most 100 Langmuirs. Articles according to the invention have low interface state density (<10.sup.11 /cm.sup.2 .multidot.eV) and interface recombination velocity (<10.sup.4 cm/s). Semiconductor/Ga.sub.2 O.sub.3 structures according to the invention can be used advantageously in a variety of electronic or optoelectronic devices, e.g.

Abstract: A controller for a power switch having an isolated control terminal and coupled to a secondary winding of a drive transformer and a method of preventing spurious turn-on of the power switch. The controller includes: (1) a controllable switch, coupled between the secondary winding and the power switch, that alters a control voltage of the power switch in response to a characteristic of the secondary winding, and (2) a bias circuit coupled to the controllable switch and the power switch that provides a voltage differential between the controllable switch and the power switch to prevent spurious turn-on thereof.

Abstract: Noise is input to a frequency generation circuit which includes a demodulator stage with a multiplier circuit in which the noise is multiplied by means of a feedback signal. The result of the multiplication in the demodulator stage is passed through a low pass filter. In a modulation wipe-off stage of the frequency generation circuit, the sign of the filtered multiplier output is extracted using a comparator circuit. The comparator circuit output is passed to a correlator circuit. In the correlator circuit, the comparator circuit output multiplies a delayed version of the input noise which is provided by a delay circuit element. The correlator circuit generates quadrature signals. Summation of the quadrature signals followed by bandpass filtering and amplitude limiting yields a discrete synthesized frequency signal.

Abstract: A single stage power converter has an energy storage device and is configured to receive electrical power. The single stage power converter includes: (1) an inductor, coupled to the energy storage device, for affecting a voltage across the energy storage device, (2) an asymmetrical half-bridge power circuit coupled to the energy storage device and having first and second power switches capable of being alternately activated to conduct current from the energy storage device to an output thereof and (3) a controller for controlling activation of the first and second power switches as a function of a characteristic of the output thereby to enhance a regulation of the output.