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Electrical and Computer Engineering

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Articles 6751 - 6780 of 7206

Full-Text Articles in Computer Engineering

Multi-Aoi-System For Easy Changing Angles Of Incidence In Ellipsometer, Polarimeter And Reflectometer Systems, Blaine D. Johs, Ping He, Martin M. Liphardt, Christopher A. Goeden, John A. Woollam, James D. Welch Feb 2005

Multi-Aoi-System For Easy Changing Angles Of Incidence In Ellipsometer, Polarimeter And Reflectometer Systems, Blaine D. Johs, Ping He, Martin M. Liphardt, Christopher A. Goeden, John A. Woollam, James D. Welch

Department of Electrical and Computer Engineering: Faculty Publications

Disclosed is a system for enabling easy sequential setting of different Angles-of-Incidence of a beam of electromagnetic radiation to a surface of a sample system, and to regression based methodology for evaluating and compensating the effects of the presence of electromagnetic beam intercepting angle-of-incidence changing systems, including where desired, parameterization of calibration parameters.

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Generalized Phase Space Projection For Nonlinear Noise Reduction, Michael T. Johnson, Richard J. Povinelli Feb 2005

Generalized Phase Space Projection For Nonlinear Noise Reduction, Michael T. Johnson, Richard J. Povinelli

Electrical and Computer Engineering Faculty Research and Publications

Improved phase space projection methods, adapted from related work in the linear signal processing field based on subspace decomposition, are presented for application to the problem of additive noise reduction in the context of phase space analysis. These methods improve upon existing methods such as Broomhead–King singular spectrum analysis projection by minimizing overall signal distortion subject to constraints on the residual error, rather than using a direct least-squares fit. This results in a range of weighted projections which estimate and compensate for the portion of the principal component's singular values corresponding to noise rather than signal energy, and which include …

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Automatic Classification And Speaker Identification Of African Elephant (Loxodonta Africana) Vocalizations, Patrick J. Clemins, Michael T. Johnson, Kirsten Leong, Anne Savage Feb 2005

Automatic Classification And Speaker Identification Of African Elephant (Loxodonta Africana) Vocalizations, Patrick J. Clemins, Michael T. Johnson, Kirsten Leong, Anne Savage

Electrical and Computer Engineering Faculty Research and Publications

A hidden Markov model (HMM) system is presented for automatically classifying African elephant vocalizations. The development of the system is motivated by successful models from human speech analysis and recognition. Classification features include frequency-shifted Mel-frequency cepstral coefficients (MFCCs) and log energy, spectrally motivated features which are commonly used in human speech processing. Experiments, including vocalization type classification and speaker identification, are performed on vocalizations collected from captive elephants in a naturalistic environment. The system classified vocalizations with accuracies of 94.3% and 82.5% for type classification and speaker identification classification experiments, respectively. Classification accuracy, statistical significance tests on the model parameters, …

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Non-Verbal Communication With Autistic Children Using Digital Libraries, Gondy A. Leroy, John Huang '05, Serena Chuang '05, Marjorie H. Charlop Jan 2005

Non-Verbal Communication With Autistic Children Using Digital Libraries, Gondy A. Leroy, John Huang '05, Serena Chuang '05, Marjorie H. Charlop

CGU Faculty Publications and Research

Autism spectrum disorder (ASD) has become one of the most prevalent mental disorders over the last few years and its prevalence is still growing. The disorder is characterized by a wide variety of symptoms such as lack of social behavior, extreme withdrawal, and problems communicating. Because of the diversity in symptoms and the wide variety in severity for those, each autistic child has different needs and requires individualized therapy. This leads to long waiting lists for therapy.

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An Electro-Oculogram Based System For Communication And Control Using Target Position Variation, Ronan Fitzmaurice, Ted Burke, Annraoi De Paor Jan 2005

An Electro-Oculogram Based System For Communication And Control Using Target Position Variation, Ronan Fitzmaurice, Ted Burke, Annraoi De Paor

Conference Papers

In this paper we describe a novel mode of human computer interaction based on gaze tracking using the electro-oculogram (EOG). Despite the relative simplicity of recording this signal, it is often discounted as a reliable method of gaze tracking because of problems arising from changing sensitivity and DC drift. We describe an original technique, Target Position Variation (TPV), which addresses this issue by presenting moving icons which, when followed with the eye, create a corresponding pattern in the EOG signal which can be used to infer the correct gaze position and to compensate for variations in sensitivity.

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Design Of Mobile Phone Applications For Point-Of-Care Test Result Validation., John Mcgrory, Owen Lynch, Eugene Coyle Jan 2005

Design Of Mobile Phone Applications For Point-Of-Care Test Result Validation., John Mcgrory, Owen Lynch, Eugene Coyle

Conference Papers

Patients with many different conditions are required to take the management of their condition into their own hands and perform Point of Care Testing (POCT) at home. However, this raises quality control issues that would not arise in a clinical setting, since the sample acquisition and testing procedures are not overseen by professional hospital staff. Another major issue, the main focus of this research, is that results from such tests are not clinically validated to ensure that they are plausible for that patient at the time of testing. In hospital, tests taken by clinicians are validated by hi-tech computerised validation …

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Preconditioning Of Primary Human Endothelial Cells With Inflammatory Mediators Alters The “Set Point” Of The Cell, Youichiro Wada, Hasan H. Otu, Shengqian Wu, Md. Ruhul Abid, Hitomi Okada, Towia Libermann, Tatsuhiko Kodama, Shu-Ching Shih, Takashi Minami, William C. Aird Jan 2005

Preconditioning Of Primary Human Endothelial Cells With Inflammatory Mediators Alters The “Set Point” Of The Cell, Youichiro Wada, Hasan H. Otu, Shengqian Wu, Md. Ruhul Abid, Hitomi Okada, Towia Libermann, Tatsuhiko Kodama, Shu-Ching Shih, Takashi Minami, William C. Aird

Department of Electrical and Computer Engineering: Faculty Publications

Endothelial cells are highly sensitive to changes in the extracellular milieu. Sepsis results in activation of inflammatory and coagulation pathways. We hypothesized that sepsis-associated mediators may alter the response capacity (so-called “set point”) of endothelial cells. Human umbilical vein endothelial cells (HUVEC) were preincubated in the presence or absence of tumor necrosis factor (TNF)-α, lipopolysaccharide (LPS), hypoxia, hyperthermia, and/or high glucose; treated with or without thrombin for 4 h; and then processed for RNase protection assays of selected activation markers. Priming with TNF-α and LPS significantly inhibited thrombin-mediated induction of vascular cell adhesion molecule-1, intercellular adhesion molecule-1, tissue factor, and …

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Observations Of The Small-Scale Variability Of Precipitation Using An Imaging Radar, Robert D. Palmer, Boon Leng Cheong, Michael Hoffman, Stephen J. Frasier, F.J. Lopez-Dekker Jan 2005

Observations Of The Small-Scale Variability Of Precipitation Using An Imaging Radar, Robert D. Palmer, Boon Leng Cheong, Michael Hoffman, Stephen J. Frasier, F.J. Lopez-Dekker

Department of Electrical and Computer Engineering: Faculty Publications

For many years, spatial and temporal inhomogeneities in precipitation fields have been studied using scanning radars, cloud radars, and disdrometers, for example. Each measurement technique has its own advantages and disadvantages. Conventional profiling radars point vertically and collect data while the atmosphere advects across the field of view. Invoking Taylor’s frozen turbulence hypothesis, it is possible to construct time-history data, which are used to study the structure and dynamics of the atmosphere. In the present work, coherent radar imaging is used to estimate the true three-dimensional structure of the atmosphere within the field of view of the radar. The 915-MHz …

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Text Degradations And Ocr Training, Elisa H. Barney Smith, Tim Andersen Jan 2005

Text Degradations And Ocr Training, Elisa H. Barney Smith, Tim Andersen

Electrical and Computer Engineering Faculty Publications and Presentations

Printing and scanning of text documents introduces degradations to the characters which can be modeled. Interestingly, certain combinations of the parameters that govern the degradations introduced by the printing and scanning process affect characters in such a way that the degraded characters have a similar appearance, while other degradations leave the characters with an appearance that is very different. It is well known that (generally speaking) a test set that more closely matches a training set will be recognized with higher accuracy than one that matches the training set less well. Likewise, classifiers tend to perform better on data sets …

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Signal Flow Analysis, Partha P. Banerjee Jan 2005

Signal Flow Analysis, Partha P. Banerjee

Electrical and Computer Engineering Faculty Publications

Signal flow graphs are a viable alternative to block diagrammatic representation of a system. What makes signal flow graphs attractive is that certain features from graph theory can be applied to the simplification and the synthesis of complex systems.

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Functional Nanoparticles In Thin Films As Sensing Media, Elena A. Guliants, Ryan Schwarb, Hope Bearbower, James R. Gord, Christopher E. Bunker Jan 2005

Functional Nanoparticles In Thin Films As Sensing Media, Elena A. Guliants, Ryan Schwarb, Hope Bearbower, James R. Gord, Christopher E. Bunker

Electrical and Computer Engineering Faculty Publications

The combination of unique properties offered by materials on the nanoscale with the increased role of surface chemistry in nanostructured solids makes core-shell nanoparticles extremely attractive for application to "smart" thin-film coatings. Sensing properties of nanoparticle-based thin films were studied in several systems containing organic-coated semiconductor and metallic particles. In semiconductors, the interaction of organic shell and/or thin-film "matrix" with the environment results in changes in the nanoparticle's surface states, altering the optical properties of the thin film. Measuring the electrical properties of thin films composed of metallic cores with hydrocarbon shells offers another mechanism to monitor the local environment …

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Design, Simulation And Tests Of A Low-Cost Microstrip Patch Antenna Arrays For The Wireless Communication, Gonca Çakir, Levent Sevgi̇ Jan 2005

Design, Simulation And Tests Of A Low-Cost Microstrip Patch Antenna Arrays For The Wireless Communication, Gonca Çakir, Levent Sevgi̇

Turkish Journal of Electrical Engineering and Computer Sciences

Typical low-cost, low-weight microstrip base station antenna arrays with beam-scanning capabilities are taken into account. In downtowns of large cities like New York, Chicago, and in historical cities like Istanbul, where high buildings are separated by narrow but densely occupied streets, antenna arrays with approximately 20°-35° beam-widths are required to complete the cellular communication coverage. To meet this requirement, new antenna arrays are designed with 35° beam-widths and 60° electronic scanning capabilities. Their characteristics are investigated both numerically and experimentally. An FDTD-based antenna simulation package (M-PATCH) is prepared, tested on canonical structures and against the literature first, for verification and …

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Soft Computing Methods In Microwave Active Device Modeling, Yavuz Cengi̇z, Fi̇li̇z Güneş, Mehmet Fati̇h Çağlar Jan 2005

Soft Computing Methods In Microwave Active Device Modeling, Yavuz Cengi̇z, Fi̇li̇z Güneş, Mehmet Fati̇h Çağlar

Turkish Journal of Electrical Engineering and Computer Sciences

In this work, the signal and noise behaviors of a microwave transistor within its operation domain (CT,V_{DS}, I_{DS}, f) are modeled by the Artificial Neural Network (ANN) and Fuzzy Logic System (FLS) without using any information on the microwave circuit theory . A worked example is presented where the same data is employed for both models selected from the manufacturer's data sheets. Performances of the FLS and ANN models are compared and conclusions are drawn.

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Fault Tolerant Control With Re-Configuring Sliding-Mode Schemes, Ufuk Demi̇rci̇, Feza Kerestecioğlu Jan 2005

Fault Tolerant Control With Re-Configuring Sliding-Mode Schemes, Ufuk Demi̇rci̇, Feza Kerestecioğlu

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a controller design method for linear MIMO systems is presented which a sliding mode controller is reconfigured in case of system faults. Faults are detected with the residual vector generated from a standard linear observer. Once a fault has been detected the fault distribution matrix can be obtained and used to update the corrective or equivalent control parts of the sliding mode controller. As a result, fault tolerant adaptive controllers keep the system performance within acceptable limits or at least avoids the system to wind-up.

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Computation Of Association Probabilities For Single Target Tracking With The Use Of Adaptive Neuro-Fuzzy Inference System, İlke Türkmen, Keri̇m Güney Jan 2005

Computation Of Association Probabilities For Single Target Tracking With The Use Of Adaptive Neuro-Fuzzy Inference System, İlke Türkmen, Keri̇m Güney

Turkish Journal of Electrical Engineering and Computer Sciences

In this study, a simple method based on the adaptive neuro-fuzzy inference system (ANFIS) is presented for computing the association probabilities. The computed association probabilities are used to track the single manoeuvring target in the cluttered environment. A hybrid learning algorithm, which combines the least square method and the backpropagation algorithm, is used to identify the parameters of ANFIS. The tracks estimated by using the method proposed in this study are in very good agreement with the true tracks. Better accuracy with respect to the well known nearest neighbour Kalman filter and probabilistic data association algorithms is obtained.

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Silhouette Based Human Motion Detection And Analysis For Real-Time Automated Video Surveillance, Murat Eki̇nci̇, Eyüp Gedi̇kli̇ Jan 2005

Silhouette Based Human Motion Detection And Analysis For Real-Time Automated Video Surveillance, Murat Eki̇nci̇, Eyüp Gedi̇kli̇

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a real-time background modeling and maintenance based human motion detection and analysis in an indoor and an outdoor environments for visual surveillance system is described. The system operates on monocular gray scale video imagery from a static CCD camera. In order to detect foreground objects, first, background scene model is statistically learned using the redundancy of the pixel intensities in a training stage, even the background is not completely stationary. This redundancy information of the each pixel is separately stored in an history map shows how the pixel intensity values changes till now. Then the highest ratio …

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Impacts Of Distributed Generators On The Oscillatory Stability Of Interconnected Power Systems, İstemi̇han Genç, Ömer Usta Jan 2005

Impacts Of Distributed Generators On The Oscillatory Stability Of Interconnected Power Systems, İstemi̇han Genç, Ömer Usta

Turkish Journal of Electrical Engineering and Computer Sciences

Integration of distributed generation is continually and gradually affecting the stability of interconnected power systems. In this paper, the impacts of distributed synchronous generators on oscillatory stability are studied. In various parameter sub-spaces of interest, feasibility regions can be calculated to determine the conditions to sustain the stable operation of an interconnected power system. Through computations of the feasibility boundaries corresponding to Hopf bifurcations of electromechanical oscillatory modes, we determine the operating limits for a stable operation of the system under small and continual disturbances such as predictable changes in loading conditions of generators. Thus, with the case studies given …

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Sigma-Delta Voltage To Frequency Converter With Phase Modulation Possibility, Milan Stork Jan 2005

Sigma-Delta Voltage To Frequency Converter With Phase Modulation Possibility, Milan Stork

Turkish Journal of Electrical Engineering and Computer Sciences

Voltage to frequency converter (VFC) is an oscillator whose frequency is linearly proportional to control voltage. There are two common VFC architectures: the current steering multivibrator and the charge-balance VFC. For higher linearity, the charge-balancing method is preferred. The charge balanced VFC may be made in asynchronous or synchronous (clocked) forms. The synchronous charge balanced VFC or "sigma delta" (\Sigma-\Delta) VFC is used when output pulses are synchronized to a clock. The charge balance VFC is more complex, more demanding in its supply voltage and current requirements, and more accurate. It is capable of 16 to18 bit linearity. In this …

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An Algorithm For Image Clustering And Compression, Meti̇n Kaya Jan 2005

An Algorithm For Image Clustering And Compression, Meti̇n Kaya

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents a new approach to image compression based on fuzzy clustering. This new approach includes pre-filtering, and fuzzy logic image enhancing to reduce undesirable noise effects on segmentation result; separation of image into 4x4 blocks and two dimensional discrete cosine transform; obtaining of peak values of cosine membership functions by combining of performing the zig-zag method with discrete cosine transform coefficients; obtaining of membership values and cluster centroids; and finally, creation of segmented image and compression. After applying the new method on sample images at different number of clusters, better compression ratio, performing time and good validity measure …

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Management Of Extremes In The Configuration Of Interoffice Telephone Switch & Priority Systems, C. Ariel Pinto Jan 2005

Management Of Extremes In The Configuration Of Interoffice Telephone Switch & Priority Systems, C. Ariel Pinto

Engineering Management & Systems Engineering Faculty Publications

This paper describes how to enable diverse enterprise customers for voice-data switch to achieve in configuration a balance among users, features, and perceived reliability subject to extremes of traffic. The analysis entailed the simulation of the voice-data switch with embedded priority system, generation of latency times for various configurations and transaction traffic rates, and the development of a framework and theoretical propositions for configuration of super-saturated systems. It was shown that the concept of tolerance levels defined in the risk of extreme events can be applied for embedded priority systems and was the basis for the application of the zone-configuration …

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Energy-Efficient Self-Organization Protocols For Sensor Networks, Qingwen Xu Jan 2005

Energy-Efficient Self-Organization Protocols For Sensor Networks, Qingwen Xu

Computer Science Theses & Dissertations

A Wireless Sensor Network (WSN, for short) consists of a large number of very small sensor devices deployed in an area of interest for gathering and delivery information. The fundamental goal of a WSN is to produce, over an extended period of time, global information from local data obtained by individual sensors. The WSN technology will have a significant impact on a wide array of applications on the efficiency of many civilian and military applications including combat field surveillance, intrusion detection, disaster management among many others. The basic management problem in the WSN is to balance the utility of the …

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Editorial, Robert W. Stewart, Michael W. Hoffman, Stephan Weiss Jan 2005

Editorial, Robert W. Stewart, Michael W. Hoffman, Stephan Weiss

Department of Electrical and Computer Engineering: Faculty Publications

In the past years, digital signal processing (DSP) algorithms and architectures for baseband communication systems have fuelled the delivery of applications such as 3G mobile communications and wireless LAN to mass markets. This was made possible by a tremendous growth in the performance of computational devices such as digital signal processors and FPGAs, as well as an increase in sampling rates of conversion devices to potentially several 100 MHz. While the development of both computational devices and ADCs/DACs continues, thus permitting DSP to be applied at IF sampling rates and possibly beyond, the opportunities for further enhancing radio devices by …

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Comparison Of Antenna Array Systems Using Ofdm For Software Radio Via The Sibic Model, Khoi D. Le, Michael W. Hoffman, Robert D. Palmer Jan 2005

Comparison Of Antenna Array Systems Using Ofdm For Software Radio Via The Sibic Model, Khoi D. Le, Michael W. Hoffman, Robert D. Palmer

Department of Electrical and Computer Engineering: Faculty Publications

This paper investigates the performance of two candidates for software radio WLAN, reconfigurable OFDM modulation and antenna diversity, in an indoor environment. The scenario considered is a 20m × 10m × 3m room with two base units and one mobile unit. The two base units use omnidirectional antennas to transmit and the mobile unit uses either a single antenna with equalizer, a fixed beamformer with equalizer, or an adaptive beamformer with equalizer to receive. The modulation constellation of the data is QPSK and 16-QAM. The response of the channel at the mobile unit is simulated using a three-dimensional indoor WLAN …

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A Novel Role For Gadd45Β As A Mediator Of Mmp-13 Gene Expression During Chondrocyte Terminal Differentiation, Kosei Ijiri, Luiz F. Zerbini, Haibing Peng, Ricardo G. Correa, Binfeng Lu, Nicole Walsh, Yani Zhao, Noboru Taniguchi, Xu-Ling Huang, Hasan H. Otu, Hong Wang, Jian Fei Wang, Setsuro Komiya, Patricia Ducy, Mahboob U. Rahman, Richard A. Flavell, Ellen M. Gravallese, Peter Oettgen, Towia A. Libermann, Mary B. Goldring Jan 2005

A Novel Role For Gadd45Β As A Mediator Of Mmp-13 Gene Expression During Chondrocyte Terminal Differentiation, Kosei Ijiri, Luiz F. Zerbini, Haibing Peng, Ricardo G. Correa, Binfeng Lu, Nicole Walsh, Yani Zhao, Noboru Taniguchi, Xu-Ling Huang, Hasan H. Otu, Hong Wang, Jian Fei Wang, Setsuro Komiya, Patricia Ducy, Mahboob U. Rahman, Richard A. Flavell, Ellen M. Gravallese, Peter Oettgen, Towia A. Libermann, Mary B. Goldring

Department of Electrical and Computer Engineering: Faculty Publications

The growth arrest and DNA damage-inducible 45β (GADD45β) gene product has been implicated in the stress response, cell cycle arrest, and apoptosis. Here we demonstrated the unexpected expression of GADD45β in the embryonic growth plate and uncovered its novel role as an essential mediator of matrix metalloproteinase-13 (MMP-13) expression during terminal chondrocyte differentiation. We identified GADD45β as a prominent early response gene induced by bone morphogenetic protein-2 (BMP-2) through a Smad1/Runx2-dependent pathway. Because this pathway is involved in skeletal development, we examined mouse embryonic growth plates, and we observed expression of Gadd45β mRNA coincident with Runx2 protein …

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Range Imaging Observations Of Pmse Using The Eiscat Vhf Radar: Phase Calibration And First Results, J. R. Fernandez, R. D. Palmer, P. B. Chilson, I. Haggstrom, M. T. Rietveld Jan 2005

Range Imaging Observations Of Pmse Using The Eiscat Vhf Radar: Phase Calibration And First Results, J. R. Fernandez, R. D. Palmer, P. B. Chilson, I. Haggstrom, M. T. Rietveld

Department of Electrical and Computer Engineering: Faculty Publications

A novel phase calibration technique for use with the multiple-frequency Range IMaging (RIM) technique is introduced based on genetic algorithms. The method is used on data collected with the European Incoherent SCATter (EISCAT) VHF radar during a 2002 experiment with the goal of characterizing the vertical structure of Polar Mesosphere Summer Echoes (PMSE) over northern Norway. For typical Doppler measurements, the initial phases of the transmitter and receiver are not required to be the same. The EISCAT receiver systems exploit this fact, allowing a multistatic configuration. However, the RIM method relies on the small phase differences between closely spaced frequencies. …

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Phased-Array Design For Biological Clutter Rejection: Simulation And Experimental Validation, B.L. Cheong, Michael Hoffman, R.D. Palmer, Stephen J. Frasier, F.J. Lopez-Dekker Jan 2005

Phased-Array Design For Biological Clutter Rejection: Simulation And Experimental Validation, B.L. Cheong, Michael Hoffman, R.D. Palmer, Stephen J. Frasier, F.J. Lopez-Dekker

Department of Electrical and Computer Engineering: Faculty Publications

This paper highlights recent results obtained with the Turbulent Eddy Profiler (TEP), which was devel- oped by the University of Massachusetts. This unique 915-MHz radar has up to 64 spatially separated receiving elements, each with an independent receiver. The calibrated raw data provided by this array could be processed using sophisticated imaging algorithms to resolve the horizontal structures within each range gate. After collecting all of the closely spaced horizontal slices, the TEP radar can produce three- dimensional images of echo power, radial velocity, and spectral width. From the radial velocity measure- ments, it is possible to estimate the three-dimensional …

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Unification Of Transactions And Replication In Three-Tier Architectures Based On Corba, Wenbing Zhao, Louise E. Moser, P. Michael Melliar-Smith Jan 2005

Unification Of Transactions And Replication In Three-Tier Architectures Based On Corba, Wenbing Zhao, Louise E. Moser, P. Michael Melliar-Smith

Electrical and Computer Engineering Faculty Publications

In this paper, we describe a software infrastructure that unifies transactions and replication in three-tier architectures and provides data consistency and high availability for enterprise applications. The infrastructure uses transactions based on the CORBA object transaction service to protect the application data in databases on stable storage, using a roll-backward recovery strategy, and replication based on the fault tolerant CORBA standard to protect the middle-tier servers, using a roll-forward recovery strategy. The infrastructure replicates the middle-tier servers to protect the application business logic processing. In addition, it replicates the transaction coordinator, which renders the two-phase commit protocol nonblocking and, thus, …

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Power Analysis And Optimization Techniques For Energy Efficient Computer Systems, Wissam Chedid, Chansu Yu, Ben Lee Jan 2005

Power Analysis And Optimization Techniques For Energy Efficient Computer Systems, Wissam Chedid, Chansu Yu, Ben Lee

Electrical and Computer Engineering Faculty Publications

Reducing power consumption has become a major challenge in the design and operation of to-day’s computer systems. This chapter describes different techniques addressing this challenge at different levels of system hardware, such as CPU, memory, and internal interconnection network, as well as at different levels of software components, such as compiler, operating system and user applications. These techniques can be broadly categorized into two types: Design time power analysis versus run-time dynamic power management. Mechanisms in the first category use ana-lytical energy models that are integrated into existing simulators to measure the system’s power consumption and thus help engineers to …

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Ultra Wide-Band : State Of The Art; Implementation Of A Performance-Controllable Low-Noise Amplifier, Serigne Dia, Balwant Godora, Frederic Alicalapa, Alain Fabre Jan 2005

Ultra Wide-Band : State Of The Art; Implementation Of A Performance-Controllable Low-Noise Amplifier, Serigne Dia, Balwant Godora, Frederic Alicalapa, Alain Fabre

Turkish Journal of Electrical Engineering and Computer Sciences

Ultra Wide-Band (UWB) transmissions exhibit performances vastly superior to existing wireless systems - superlative data-rate capacity, high security, low cost, low power consumption - and are emerging as the hottest topic of research for upcoming wireless generations. This communication protocol is studied in detail, with mention of the history and estimates for the near future; the present and possible applications are mentioned; the advantages and unresolved issues are detailed; a typical UWB transceiver architecture is studied; the modulation and coding schemes are enumerated; and the possibility of long-range communication is touched upon. Finally, a new performance-controllable low-noise amplifier (LNA) destined …

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A New Cmos Differential Otra Design For The Low Voltage Power Supplies In The Sub-Micron Technologies, Alper Duruk, Hakan Kuntman Jan 2005

A New Cmos Differential Otra Design For The Low Voltage Power Supplies In The Sub-Micron Technologies, Alper Duruk, Hakan Kuntman

Turkish Journal of Electrical Engineering and Computer Sciences

In this study, a new CMOS differential OTRA topology is proposed. This topology can operate with a very low voltage power supply as \pm 0.6V. In this design, CMOS 0.13 \mu m STMicroelectronics technology transistor models are used for the simulations. The designed CMOS OTRA has a transresistance gain (Rm) of 7478 V/I with a 28.1 MHz bandwidth (-3 dB) and a transresistance unity-gain bandwidth of 2 GHz. To demonstrate the performance of the OTRA, designed low pass, high pass and band pass filters employing a single CMOS differential OTRA and passive elements are tested with SPICE simulation program to …

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