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IEEE Convention of the electrical and electronic Engineers in Israel

作者： Stanley R. Rotman Irena Yatskaer Department of Electrical and Computer Engineering Ben-Gurion University of the Negev Israel S.R. Rotman supervision from Electro-optics Department Ben-Gurion University of the Negev Israel

The analysis of hyperspectral imagery promises to provide technical solutions to problems in many areas of research; this is particularly true of target acquisition. Exploiting high spectral resolution data contributes greatly to the discrimination power of standard image processing techniques. This additional dimension of information is based on the physical characteristics of the target material under consideration. The present research addresses the problem of the detection of a point target, moving with sub-pixel velocity, from a time sequence of hyperspectral data cubes. The emphasis in this paper will be on the degree of improvement in target detection algorithms that can be expected as a function of the degree of difference between the target and background signatures. Differences obtained between the use of real spectral signatures, compared to synthetic ones, for the noise, background and target end-members, and their implication on the detection results will be discussed. The standard matched filter for target detection is broadened and improved by advanced non-data dependent techniques. In order to estimate algorithm performance, five different tests (detection methods of varying sophistication) were applied to the real hyper-spectral data. The results were compared to the synthetic data outcome; conclusions regarding the threshold needed for spectral differences for the target detection to be notably improved are reached. The major focus of the research is a comparative understanding of the target detection results in different scenarios: strongly, partially and lightly cluttered sequences.

关键词： Object detection Hyperspectral imaging Clouds Matched filters Detection algorithms Image analysis Image resolution Image processing Background noise Testing

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DCT-Domain Coder for Digital Video Applications

DCT-Domain Coder for Digital Video Applications

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International Conference on Information Technology: Research and Education (ITRE)

作者： Alex Ginzburg Evgeny Kaminsky Yuri Abramov Ofer Hadar Unit of Electro-Optics Engineering Ben-Gurion University of the Negev Israel Department of Electrical and Computer Engineering Ben-Gurion University of the Negev Israel Soliton Har Hatzofim 24/4 Holon 58492 Israel yuri_a@*** Department of Communication Systems Engineering Ben-Gurion University of the Negev Israel

Recent home networking services such as next generation game consoles, video-on-demand, HDTV, etc. require faster video encoders and transcoders that avoid over-complicated transformations. In most popular digital video coding standards such as MPEG-X or H.26x, discrete cosine transform (DCT), inverse DCT (IDCT) transform, and block matching algorithms are essential elements in the coding process. The transforms between the pixel and DCT domains, are taking place during the operations and being only intermediate calculations, which complicate the encoding process. Thus, it is advantageous to reduce the number of transform operations between the spatial and frequency domains in order to simplify the overall encoder structure. In this paper we propose a DCT domain video encoder for reducing processing time. This is achieved by excluding the intermediate DCT and IDCT transforms from the conventional hybrid encoder. This is achieved by calculating the motion estimation and motion compensation via a spatial relationship between the DCT coefficients of a specific block and its sub- blocks. Experimental results of this method were compared to those of the conventional hybrid video encoder in the sense of visual quality and computational complexity. The comparison shows that the computational complexity of the proposed encoder is lower by 12.5% in comparison to conventional hybrid video coder for the same visual quality.

关键词： Discrete cosine transforms Discrete transforms Computational complexity Next generation networking Games HDTV Video coding Encoding Frequency domain analysis Motion estimation

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Adhesive Bonding Process Development for Planar Lightwave Circuit in Optical Transceiver Assembly

Adhesive Bonding Process Development for Planar Lightwave Ci...

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International Symposium on Advanced Packaging Materials

作者： Cai Liang Xiaofeng Zhou Fajian Zhang Materials engineering Samuel Ginn College of Engineering Aubum University Auburn AL USA OptoNet Inc. Evanston IL USA Fiber & Electro-optics research center The Bradley Department of Electrical & Computer Engineering Virginia Polytechnic Institute and State University Blacksburg VA USA

Glass based planar lightwave circuit (PLC) is one of the core components employed in optical transceiver operation. Assembly of PLC onto a silicon optical bench (SiOB) is a crucial step, since it requires actively aligning the PLC to both a laser diode and an optical fiber. We have successfully developed an adhesive bonding process for buried type planar glass wave-guide circuit assembly in optical transceiver packaging with the powerful design optimal experiment tool. A dosage of 280j/cm 2 with intensity of 15000mw/cm 2 UV curing followed by 15 minutes 110degC thermal cure process is able to achieve 0.2dB optical coupling power loss for PLC-fiber assembly

关键词： Bonding processes Circuits Transceivers Assembly programmable control Glass Optical devices Silicon Diode lasers Optical fibers

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Quantum Cascade Terahertz Emitters for Subsurface Defect Detection

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AIP Conference Proceedings 2006年第1期820卷 500-507页

作者： Adam T. Cooney Andrew M. Sarangan Thomas R. Nelson Rashid Alkuwari Peter E. Powers Andres Rodriguez Mark Kleeman Gary Lamont James L. Blackshire Joseph W. Haus Air Force Research Lab (AFRL/MLLP) Wright‐Patterson AFB OH 45433 University of Dayton Electro‐Optics Department 300 College Park Dayton OH 45469 Air Force Research Lab (AFRL/SNDD) Wright‐Patterson AFB OH 45433 Air Force Institute of Technology Electrical and Computer Engineering Department Wright‐Patterson AFB OH 45433

The transmission and penetration capability of electromagnetic waves with terahertz frequencies promises nondestructive subsurface inspection capabilities using low energy, non‐harmful radiation. The development of compact and portable terahertz frequency radiation sources and detectors is crucial to the practical implementation of future terahertz based nondestructive evaluation tools for aerospace, medical, security, and electronic industries. Recent progress in the bandstructure engineering of multi‐quantum well heterostructures offers the potential to design miniature, efficient, high power, and direct terahertz emitters using standard semiconductor materials and fabrication techniques. Using a recently developed terahertz spectrometer, combined with near and mid‐infrared spectroscopy data, we report on the transmission characteristics of aerospace coatings over a broad spectrum from near‐infrared to terahertz frequencies. The design of quantum cascade emitters based on the obtained transmission data is presented.

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DNA- New class of polymer

DNA- New class of polymer

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Organic Photonic Materials and Devices VIII

作者： Grote, James G. Heckman, Emily M. Hagen, Joshua A. Yaney, Perry P. Diggs, Darnell E. Subramanyam, Guru Nelson, Robert L. Zetts, John S. Zang, De Yu Singh, Birendra Sariciftci, Niyazi Serdar Kenneth Hopkins, F. US Air Force Research Laboratory Materials and Manufacturing Directorate Wright-Patterson AFB OH 45433-7707 United States Anteon Corporation 5100 Springfield Pike Dayton OH 45431 University of Dayton Electro-Optics Department Dayton OH 45469 United States University of Cincinnati Department of Chemical and Materials Engineering Cincinnati OH 45221 United States Department of Physics University of Dayton Dayton OH 45469-2314 University of Dayton Electrical and Computer Engineering Department Dayton OH 45469 United States Ipitek Corporation 2330 Faraday Avenue Carlsbad CA 92008 United States Linz Institute for Organic Solar Cells Physical Chemistry Johannes Kepler University of Linz A-4040 Linz Austria

ISBN: (纸本)0819461598

Suitable organic and polymeric based materials for electronic and photonic applications must possess the desired electromagnetic and optical properties to achieve optimal device performance in order to be more competitive with their inorganic counterparts. A new class of biopolymer, processed from purified marine-based deoxyribonucleic acid (DNA), has been investigated for use in both electronic and photonic applications and has demonstrated promise as an excellent dielectric and optical waveguide material. In this paper we present examples of devices using this new DNA-based biopolymer.

关键词： Biopolymers

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A genetic algorithm for the optimization of cable routing

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Systems and computers in Japan 2006年第7期37卷 61-71页

作者： Ma, Xuan Iida, Kazuhiro Xie, Mengchun Nishino, Junji Odaka, Tomohiro Ogura, Hisakazu Graduate School of Engineering University of Fukui Fukui City 910-8507 Japan Wakayama National College of Technology Gobo City 644-0023 Japan Faculty of Automation and Information Engineering Xi an University of Technology B Techno College Department of Electrical and Computer Engineering Wakayama National College of Technology Information Processing Society of Japan China Mechanical Design Society Department of Systems Engineering University of Electro-Communications Japan Society for Fuzzy Theory and Intelligent Informatics Japanese Academy of Facial Studies Japan Society of Kansei Engineering Graduate Program of Nuclear Power and Energy Safety Engineering Graduate School of Engineering Fukui University IEEE CS ACM IPSJ IEICE JSMBET Department of Human and Artificial Intelligent Systems JSAI Japan SOFT IEEE

In this paper the authors propose a structural method for a genetic algorithm (GA) for the optimization problem of cable routing in which cables have to be laid optimally. When there are no limits on the layout routes, the optimal routes for the individual cables can be found using the Dijkstra method in a finite discrete graph. However, when there are limits on the capacity in the layout routes, optimization cannot be performed using the Dijkstra method. The proposed GA is a two-level hierarchical GA that uses chromosome coding involving two levels. The routes for each cable and the combinations of cable routes are defined respectively, and layout route selection is optimized overall through genetic operations involving these levels. Block crossover and block mutation are used as genetic operations in the first level. In addition, a method to take advantage of lethal genes, which do not satisfy the constraints and are generated in the second level is used. computer simulations confirm that the two-level hierarchical GA with these genetic operations functions effectively for the optimization problem of cable routing. © 2006 Wiley Periodicals, Inc.

关键词： Electric cable laying

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The assessment of four different correction methods applied to the diffuse radiation measured in Jerusalem, Israel

The assessment of four different correction methods applied ...

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Solar World Congress 2005: Bringing Water to the World, Including 34th ASES Annual Conference and 30th National Passive Solar Conference

作者： Kudish, Avraham I. Rahima, Tal Solar Energy Laboratory Institutes for Applied Research Ben-Gurion University of the Negev Beer Sheva 84105 Israel Electro-Optics Unit Department of Electrical and Computer Engineering Ben-Gurion University of the Negev Beer Sheva 84105 Israel

ISBN: (纸本)9781622762637

Four different correction methods were applied to the diffuse radiation measured by a shadow ring at the National Physical Laboratory's meteorological station during the years 2000-2002. The database consisted of global, normal incidence beam, and diffuse radiation. The diffuse radiation was measure by both an occulting disk and a shadow ring instruments. The database was analyzed by two different filtering methods to eliminate spurious measurements. The database was divided into subsets consisting of clear, partially cloudy and cloudy hours based upon the magnitude of the clearness index. The correction models were applied to all the data, viz., irrespective of the magnitude of the hourly clearness index, and the three subsets defined by the magnitude of the hourly clearness index. It was observed that the performance of the correction model was contingent upon both quality control filters applied and the data set analyzed.

关键词： Database systems

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Optimal transrating via DCT coefficients modification and dropping

Optimal transrating via DCT coefficients modification and dr...

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International Conference on Information Technology: Research and Education (ITRE)

作者： S. Benyaminovich O. Hadar E. Kaminsky Electro-Optics Unit Ben-Gurion University of the Negev Beer-Sheva Israel Department of Communication Systems Engineering Ben-Gurion University of the Negev Beer-Sheva Israel Department of Electrical and Computer Engineering Ben-Gurion University of the Negev Beer-Sheva Israel

Coefficient dropping is a common tool for video transrating in order to adapt it to various network bandwidth constraints. Several recent works propose Lagrangian optimization for finding the optimal retained coefficients for each coded block to achieve the desired bit-rate with minimum distortion. In this paper we extend the Lagrangian optimization procedure by modifying the coefficients prior to dropping them. The purpose of this Lagrangian extension is to provide higher PSNR than other coefficient dropping methods without increasing computational complexity significantly.

关键词： Discrete cosine transforms Streaming media Video compression Transform coding Lagrangian functions Bit rate Systems engineering and theory Bandwidth Web and internet services Distortion measurement

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Deoxyribonucleic acid (DNA) based photonic materials - Current status

Deoxyribonucleic acid (DNA) based photonic materials - Curre...

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Optically Based Biological and Chemical Sensing, and Optically Based Materials for Defence

作者： Grote, James G. Heckman, Emily M. Hagen, Joshua A. Yaney, Perry P. Diggs, Darnell E. Subramanyam, Guru Nelson, Robert L. Zetts, John S. De Zang, Yu Kenneth Hopkins, F. US Air Force Research Laboratory Materials and Manufacturing Directorate Wright-Patterson AFB OH 45433-7707 United States Anteon Corporation 5100 Springfield Pike Dayton OH 45431 University of Dayton Electro-Optics Department Dayton OH 45469 United States University of Cincinnati Department of Chemical and Materials Engineering Cincinnati OH 45221 United States Department of Physics University of Dayton Dayton OH 45469-2314 University of Dayton Electrical and Computer Engineering Department Dayton OH 45469 United States Ipitek Corporation 2330 Faraday Avenue Carlsbad CA 92008 United States

Suitable polymer-based photonic materials must possess the desired optical and electromagnetic properties for optimal device performance depending on the intended application. A new class of polymer, processed from purified deoxyribonucleic acid (DNA), has been investigated for use in photonic applications and has shown promise as an excellent optical waveguide material. In this paper we present the current optical and electronic properties of this new DNA-based biopolymer, including optical loss, temperature stability, refractive index, resistivity, dielectric constant and microwave insertion loss.

关键词： DNA

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Carbon nanotubes: Anomalous photo-galvanic effect, electromechanical instability, and IR detection

Carbon nanotubes: Anomalous photo-galvanic effect, electrome...

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Frontiers in optics, FiO 2005

作者： Rakitin, A. Meĺnikov, I.V. Haus, J.W. Aitchison, J.S. Department of Physics and Astronomy York University 4700 Keele Street North York Ontario M3P 1P3 Canada Comtex Consulting Inc 162 Princess Margaret Boulevard Etobicoke Ontario M9B 2Z5 Canada Electro-Optics Program School of Engineering University of Dayton 300 College Park Dayton Ohio 45469-0245 United States The E. S. Rogers Sr. Department of Electrical and Computer Engineering University of Toronto 10 King's College Road Toronto. Ontario M5S 3G4 Canada

ISBN: (纸本)1557527970

Carbon nanotubes (CNTs) are hollow cylinders composed of one or more concentric layers of carbon atoms arranged in a honeycomb lattice. CNTs are widely considered as an elemental material for a future nanoelectronic technology. This is not simply due to their small size but rather to their overall properties: CNTs are known to exhibit either metallic or semiconducting behaviour, with the band gap being dependent on the nanotube diameter. Both active devices (transistors) and interconnects can be made out of semiconducting and metallic nanotubes, respectively. The key nanotube dimension, their diameter, is controlled by chemistry, not conventional fabrication. The strong covalent bonding gives the CNTs high mechanical and thermal stability and ability to sustain current densities as high as 10 A/cm2.

关键词： Atoms Carbon nanotubes Chemistry Curvature Infrared detection Scattering

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