Abstract: An AlGaN composition is provided comprising a group III-Nitride active region layer, for use in an active region of a UV light emitting device, wherein light-generation occurs through radiative recombination of carriers in nanometer scale size, compositionally inhomogeneous regions having band-gap energy less than the surrounding material. Further, a semiconductor UV light emitting device having an active region layer comprised of the AlGaN composition above is provided, as well as a method of producing the AlGaN composition and semiconductor UV light emitting device, involving molecular beam epitaxy.

Abstract: This invention presents a super-resolution image reconstruction from a sequence of aliased imagery. The sub-pixel shifts (displacement) among the images are unknown due to uncontrolled natural jitter of the imager. A correlation method is utilized to estimate sub-pixel shifts between each low resolution aliased image with respect to a reference image. An error-energy reduction algorithm is derived to reconstruct the high-resolution alias-free output image. The main feature of this proposed error-energy reduction algorithm is that we treat the spatial samples from low-resolution images that possess unknown and irregular (uncontrolled) sub-pixel shifts as a set of constraints to populate an over-sampled (sampled above the desired output bandwidth) processing array. The estimated sub-pixel locations of these samples and their values constitute a spatial domain constraint.

Abstract: Methods and devices for creating an anisotropic strain in a semiconductor quantum well structure to induce anisotropy thereof are disclosed herein. Initially, a substrate is provided, and a quantum well structure formed upon the substrate. A first crystalline layer (e.g., a GaAs layer) having a first crystalline phase can then be deposited upon the quantum well structure. Thereafter, a second crystalline layer (e.g., a GaN layer) having a second crystalline phase and a thickness thereof can be formed upon the first crystalline layer to thereby induce an anisotropic strain in the quantum well structure to produce a quantum well device thereof. Additionally, the second crystalline layer (e.g., GaN) can be formed from a transparent material and utilized as an anti-reflection layer. By properly choosing the thickness of the second crystalline layer (e.g., a GaN layer), a desired anisotropic strain as well as a desired anti-reflection wavelength can be achieved.

Abstract: Feature attributes are extracted from an observation space to create feature vectors for each class to be identified. A linear transformation matrix is used to reduce the dimension of the feature vectors. A numerical optimization algorithm maximizes a geometric criterion function in order to calculate the linear transformation matrix, where it exploits the geometry of the class contours of constant density. Next, a classifier based on the feature vectors in a lower dimension is generated and a class is determined for the data represented.

Abstract: Method for geolocating logical network addresses on electronically switched dynamic communications networks, such as the Internet, using the time latency of communications to and from the logical network address to determine its location. Minimum round-trip communications latency is measured between numerous stations on the network and known network addressed equipment to form a network latency topology map. Minimum round-trip communications latency is also measured between the stations and the logical network address to be geolocated. The resulting set of minimum round-trip communications latencies is then correlated with the network latency topology map to determine the location of the network address to be geolocated.

Abstract: Method of image binarization using histogram modeling, which combines spatial resolution expansion with binarization in a single integrated process using a combination of spatial expansion, histogram modeling, classification, and quantization. Each pixel of the input image is expanded into a higher resolution image, and a count of the number of times each distinct gray scale intensity value occurs in the input image is calculated from pixel values of the input image and then modeled with an approximate histogram that is computed as the sum of weighted modeling functions. The input pixel values are then classified using the modeling functions and the results of the pixel classification are used to quantize the high resolution gray scale image to create a binary output image.

Abstract: A semi-fragile image tamper detection system and method based on thumbnail hiding and which signifies the image areas in which tampering has occurred, is provided. A thumbnail is defined as a low-resolution version of an entire image or the significant features of an entire image. Thumbnail hiding is chosen to be resilient to effects of both image compression and low levels of transmission channel noise. The thumbnail computation and embedding techniques are chosen such that the resultant marked image corresponds in size and dynamic range to the original image.

Abstract: A security paper shredder where the residue of individual shredded document pages are collected in multiple collection bins for disposal, ensuring that no single collection bin contains the residue of any entire page. To further ensure that no adversary could obtain the contents of all the multiple collection bins and reassemble the document, the contents of the collection bins are disposed of at differing times and in geographically dispersed locations.

Abstract: Method to measure gain of a photonic inverter based on a semiconductor laser using two different modes of operation. In one mode, the device is operated as a photonic inverter device and in the other mode as a photogenerated current measurement device. While the device is operated in a photonic inverter mode, that is, pumped at a magnitude that supports photonic inverter operation, the optical output power is measured in the absence of an input signal and with an input signal that quenches the output of the photonic inverter. While the device is operated as a photogenerated current measurement device with an input optical signal, a reverse bias is applied to offset any forward bias induced by the injected input optical signal, the induced photocurrent is measured, and the wavelength of the input optical signal is measured.

Abstract: All-optical timing extraction and optical clock recovery for high-speed return-to-zero binary optical data streams using the timing difference between clock and data counter-propagating optical pulses in a non-linear optical waveguide where the first pulse to arrive at the non-linear optical waveguide partially saturates the transmission properties of the waveguide resulting in a change of the transmission properties seen by the lagging pulse. A balanced photo-detector makes delay-dependent comparisons of the clock and data pulses' peak power and generates an error signal used in a phase-locked loop configuration to synchronize the clock to the data stream.

Abstract: Device whereby one or more bands of optical wavelengths may be selected for further transmission. All light within the optical bandwidth of operation is first coupled from the core mode of an optical fiber to a specific cladding mode by a chirped broadband cladding mode coupler. These cladding mode lightwaves then enter a narrow-band core mode coupler whereby selected optical bands of wavelengths, tuned by the tension on the optical fiber, are re-coupled back into the core of the optical fiber. The chirped broadband cladding mode coupler is isolated from the narrow-band core mode coupler by an acoustic absorber to limit the acoustic interaction between them.

Abstract: A language-independent speaker-recognition system based on parallel cumulative differences in dynamic realization of phonetic features ( i.e. , pronunciation) between speakers rather than spectral differences in voice quality. The system exploits phonetic information from many phone recognizers to perform text independent speaker recognition. A digitized speech signal from a speaker is converted to a sequence of phones by each phone recognizer. Each phone sequence is then modified based on the energy in the signal. The modified phone sequences are tokenized to produce phone n-grams that are compared against a speaker and a background model for each phone recognizer to produce log-likelihood ratio scores. The log-likelihood ratio scores from each phone recognizer are fused to produce a final recognition score for each speaker model. The recognition score for each speaker model is then evaluated to determine which of the modeled speakers, if any, produced the digitized speech signal.

Abstract: A device whereby one or more bands of optical wavelengths may be selected for further transmission. All light within the optical bandwidth of operation is first coupled from the core mode of an optical fiber to a specific cladding mode by a chirped broadband cladding mode coupler. These cladding mode lightwaves then enter a narrow-band core mode coupler whereby selected optical bands of wavelengths are re-coupled back into the core of the optical fiber. The chirped broadband cladding mode coupler is isolated from the narrow-band core mode coupler by an acoustic absorber to limit the acoustic interaction between them.

Abstract: The acousto-optic bandpass filter is a device whereby one or more bands of optical wavelengths may be selected for further transmission. In this device, all light within the optical bandwidth of operation is first coupled from the core mode of a optical fiber to a specific cladding mode by a long-period photo-induced grating. These cladding mode lightwaves then enter an acousto-optic interaction region where selected RF frequencies of flexure waves, induced by an acoustic wave amplifier, re-couple selected bands of wavelengths back into the core mode. The interaction region is isolated from the broadband coupler by an acoustic absorber to limit acoustic interaction to the interaction region.

Abstract: A method of constructing graph abstractions using a computer is described. The abstraction is presented on a computer display and used by a human viewer to understand a more complicated set of raw graphs. The method provides rapid generation of an abstraction that offers an arbitrary composition graph of vertices into composite vertices, dispersing and marshaling of composite vertices, arbitrary hiding and showing of portions of the composition, and marking of points of elision.

Abstract: A method of lattice-quantizing an eight-long data point to minimize storage requirements by acquiring the data point, multiplying each coordinate of the data point by {square root over (2)} to form an inflated data point, rounding each coordinate of the rounded and inflated data point to the nearest integer, modulo-two reducing each coordinate of the rounded and inflated data point to form an initial codeword, multiplying a parity-check matrix of an eight-bit Extended Hamming Code by the result of the last step to form a syndrome, correcting any single-bit errors and double-bit errors, if any, in the initial codeword and the rounded and inflated data point, transforming the coordinate system of the initial codeword to an extended quadratic residue form, creating a signal packet, and transmitting the signal packet to a receiver.

Abstract: A method of full-text scanning for matches in a large dictionary of keywords is described, suitable for SDI (selective dissemination of information). The method is applicable to large dictionaries (hundreds of thousands of entries) and to arbitrary byte sequences for both patterns and sample streams. The approach employs Boyer-Moore-Horspool skipping, extended to pattern collections and digrams, followed by an n-gram hash test, which also identifies a subset of feasible keywords for conventional pattern matching at each location of a putative match.

Abstract: A method and apparatus providing full-text scanning for matches in a large dictionary is described. The invention is suitable for SDI (selective dissemination of information) systems, accommodating large dictionaries (104 to 105 entries) and rapid processing. A preferred embodiment employs a hardware primary test on a single commercially-available gate-array board hosted by a computer, in which a software secondary test is conducted. No delimiter cues such as spaces or punctuation are required.

Abstract: A network firewall security apparatus that enables a very high degree of traffic selectability yet avoids the usual performance penalty associated with firewalls. This approach is specific to high-speed circuit switched networks, Asynchronous Transfer Mode (ATM) networks in particular. Security management is achieved through active connection management with authentication, better suited to the cell-based environment of high-speed circuit switched networks and to the mix of circuit switched traffic, where Internet Protocol (IP) datagrams comprise a fraction of the total traffic. The information in the signaling cells is used to determine which flows, rather than which individual cells, are allowed to pass through the firewall. A hierarchical method has been devised, in which the physical location of the interrelated components may be decoupled. Active connection management is applied in determining the approval of a connection based on signaling information and network state information.

Abstract: A method of lattice quantizing a 24-long data point to minimize storage requirements by acquiring the data point, multiplying each coordinate of the data point by the square root of 8 to form an inflated data point, finding the closest point of the inflated Leech lattice by any method, creating a signal packet, and transmitting the packet to a receiver.