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2006

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Ac/Dc Power Systems With Applications In Future Human Habitat On Lunar And Mars Bases, Badrul H. Chowdhury, Sabbir A. Hossain, James T. Lawrence, Sushant Barave Jan 2006

Ac/Dc Power Systems With Applications In Future Human Habitat On Lunar And Mars Bases, Badrul H. Chowdhury, Sabbir A. Hossain, James T. Lawrence, Sushant Barave

Electrical and Computer Engineering Faculty Research & Creative Works

As NASA readies itself for new space exploration initiatives starting with a human return to the Moon by the year 2020 eventually leading to human exploration of Mars, the requirements for a safe, efficient and comprehensive power system to support the exploration missions as well human habitat will become important issues to consider. Certain issues dealing with electric power generation and distribution on board Mars-bound vehicles and those on Lunar and Martian surfaces are described. The requirements for lightweight power generation dictates the use of a high frequency ac machine. Preliminary results of investigating the design of a permanent magnet …

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An Interval Type-Ii Robust Fuzzy Logic Controller For A Static Compensator In A Multimachine Power System, Salman Mohagheghi, Ganesh K. Venayagamoorthy, Ronald G. Harley Jan 2006

An Interval Type-Ii Robust Fuzzy Logic Controller For A Static Compensator In A Multimachine Power System, Salman Mohagheghi, Ganesh K. Venayagamoorthy, Ronald G. Harley

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents a novel fuzzy logic based controller for a Static Compensator (STATCOM) connected to a power system. Type-II fuzzy systems are selected that enable the controller to deal with design uncertainties and the noise associated with the measurements in the power system. Interval type-II fuzzy is computationally more effective than the ordinary type-II fuzzy systems and is more suitable for the power network with fast changing dynamics. Using a proportional-integrator approach the proposed controller is capable of dealing with actual rather than deviation signals. The STATCOM is connected to a multimachine power system in order to provide extra …

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A Comparison Of Diode-Clamped And Cascaded Multilevel Converters For A Statcom With Energy Storage, Ying Cheng, Chang Qian, Mariesa Crow, Steven Pekarek, Stan Atcitty Jan 2006

A Comparison Of Diode-Clamped And Cascaded Multilevel Converters For A Statcom With Energy Storage, Ying Cheng, Chang Qian, Mariesa Crow, Steven Pekarek, Stan Atcitty

Electrical and Computer Engineering Faculty Research & Creative Works

The progression of distributed generation within a bulk power system will lead to the need for greater control of transmission-line power flows. Static synchronous compensators (STATCOMs) provide a power-electronics-based means of embedded control of transmission-line voltage and power flows. The integration of energy storage with a STATCOM can extend traditional STATCOM capabilities to four-quadrant power flow control and transient stability improvement. This paper discusses energy storage systems (ESSs) integrated with conventional and multilevel bidirectional power converters for a hybrid STATCOM/ESS. Conventional, diode-clamped, and cascaded multilevel converter-based STATCOM/ESSs are developed, and their performances for a variety of power system applications are …

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Efficient Mining Of Group Patterns From User Movement Data, Yida Wang, Ee Peng Lim, San-Yih Hwang Jan 2006

Efficient Mining Of Group Patterns From User Movement Data, Yida Wang, Ee Peng Lim, San-Yih Hwang

Research Collection School Of Computing and Information Systems

In this paper, we present a new approach to derive groupings of mobile users based on their movement data. We assume that the user movement data are collected by logging location data emitted from mobile devices tracking users. We formally define group pattern as a group of users that are within a distance threshold from one another for at least a minimum duration. To mine group patterns, we first propose two algorithms, namely AGP and VG-growth. In our first set of experiments, it is shown when both the number of users and logging duration are large, AGP and VG-growth are …

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Cbc.Ca - Broadcast Sovereignity In A Digital Environment, Brian O'Neill Jan 2006

Cbc.Ca - Broadcast Sovereignity In A Digital Environment, Brian O'Neill

Articles

Canadian Broadcasting Corporation (CBC), like many public broadcasters, has identified the value of branding their services on the world wide web as a crucial element in the strategy to bring radio into the digital era. Their approach highlights a number of strategically important issues facing broadcasters in the current environment. The internet, in Canadian terms, is an unregulated space and a not particularly Canadian space. Just as in the terrestrial environment, broadcasters like CBC have to operate in an environment dominated by United States-based interests. The regulatory solutions that Canada has previously pursued in order to preserve cultural sovereignty may …

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Towards An Inverse Constant Q Transform, Derry Fitzgerald, Matt Cranitch, Marcin T. Cychowski Jan 2006

Towards An Inverse Constant Q Transform, Derry Fitzgerald, Matt Cranitch, Marcin T. Cychowski

Conference papers

The Constant Q transform has found use in the analysis of musical signals due to its logarithmic frequency resolution. Unfortunately, a considerable drawback of the Constant Q Transform is that there is no inverse transform. Here we show it is possible to obtain a good quality approximate inverse to the Constant Q transform provided that the signal to be inverted has a sparse representation in the Discrete Fourier transform domain. This inverse is obtained through the use of lo and l1 minimisation approaches to project the signal from the constant Q domain back to the Discrete Fourier Transform domain. Once …

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A Comparison Of Time-Domain Time-Scale Modification Algorithms, David Dorran, Robert Lawlor, Eugene Coyle Jan 2006

A Comparison Of Time-Domain Time-Scale Modification Algorithms, David Dorran, Robert Lawlor, Eugene Coyle

Conference papers

Time-domain appraoches to time-scale modification are popular due to their ability to produce high quality results at a relatively low computational cost. Within the category of time-domain implementations quite a number of alternatives exist, each with their own computational requirements and associated output quality. This paper provides a computational and objective output quality assessment of a number of popular time-domain time-scaling implmentations; thus providing a means for developers to identify a suitable algorithm for their application of interest. In addition, the issues that should be considered in developing time-domain algorithms are outlines, purely in the context of a waveform editing …

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Architecture Of The Millennium: Catharine Beecher, Domestic Economy, And Social Reform, Erie M. Roberts Jan 2006

Architecture Of The Millennium: Catharine Beecher, Domestic Economy, And Social Reform, Erie M. Roberts

Constructing the Past

This article discusses Catherine Beecher's ideas about how women, as the Christian moral center and teachers, could reform American society. She put homemakers at a center of power, since she believed that they would be able to not only teach children to become true Christian citizens, but reform men as well.

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"Connected And Unified?": A More Critical Look At Frederick Jackson Turner's America, Megan Mondi Jan 2006

"Connected And Unified?": A More Critical Look At Frederick Jackson Turner's America, Megan Mondi

Constructing the Past

This article critiques Turner's view of American westward expansion, especially his assertion that Americans have a unified experience and set of characteristics.

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Reflection On Contemporary Issues In Relationship Marketing: Evidence From A Longitudinal Case Study In The Building Materials Industry, Aidan O'Driscoll Jan 2006

Reflection On Contemporary Issues In Relationship Marketing: Evidence From A Longitudinal Case Study In The Building Materials Industry, Aidan O'Driscoll

Articles

This article examines a number of issues in relationship marketing through the perspective of the competence based view of the firm. It draws on data from a 53-year case history of a firm in the Irish building materials industry. Relationship marketing emerges from this data as a significant market-related competence helping the firm to enjoy a preeminent position in the marketplace over five decades. Discussion focuses on the dynamic nature of relationship marketing in the company − how the intent, thrust and characteristics of relationship marketing evolved over 53 years and five eras of the firm’s history. In this context, …

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Lung Nodule Detection In Screening Computed Tomography, I Gori, R Bellotti, P Cerello, Sc Cheran, Et Al Jan 2006

Lung Nodule Detection In Screening Computed Tomography, I Gori, R Bellotti, P Cerello, Sc Cheran, Et Al

School of Biomedical Sciences

A computer-aided detection (CAD) system for the identification of pulmonary nodules in low-dose multi-detector helical Computed Tomography (CT) images with 1.25 mm slice thickness is presented. The basic modules of our lung-CAD system, a dot-enhancement filter for nodule candidate selection and a neural classifier for false-positive finding reduction, are described. The results obtained on the collected database of lung CT scans are discussed.

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A Mathematical Formulation Of Dna Computation, Mingjun Zhang, Maggie Xiaoyan Cheng, Tzyh-Jong Tarn Jan 2006

A Mathematical Formulation Of Dna Computation, Mingjun Zhang, Maggie Xiaoyan Cheng, Tzyh-Jong Tarn

Computer Science Faculty Research & Creative Works

DNA computation is to use DNA molecules for information storing and processing. The task is accomplished by encoding and interpreting DNA molecules in suspended solutions before and after the complementary binding reactions. DNA computation is attractive, due to its fast parallel information processing, remarkable energy efficiency, and high storing capacity. Challenges currently faced by DNA computation are (1) lack of theoretical computational models for applications, and (2) high error rate for implementation. This paper attempts to address these problems from mathematical modeling and genetic coding aspects. The first part of this paper presents a mathematical formulation of DNA computation. The …

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Model Checking Control Communication Of A Facts Device, Bruce M. Mcmillin, J. K. Townsend, David Cape Jan 2006

Model Checking Control Communication Of A Facts Device, Bruce M. Mcmillin, J. K. Townsend, David Cape

Computer Science Faculty Research & Creative Works

This paper concerns the design and verification of a realtime communication protocol for sensor data collection and processing between an embedded computer and a DSP. In such systems, a certain amount of data loss without recovery may be tolerated. The key issue is to define and verify the correctness in the presence of these lost data frames under real-time constraints. This paper describes a temporal verification that if the end processes do not detect that too many frames are lost, defined by comparison of error counters against given threshold values, then there will be a bounded delay between transmission of …

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Multimedia Correlation Analysis In Unstructured Peer-To-Peer Network, Bo Yang, A. R. Hurson, Yu Jiao, Thomas E. Potok Jan 2006

Multimedia Correlation Analysis In Unstructured Peer-To-Peer Network, Bo Yang, A. R. Hurson, Yu Jiao, Thomas E. Potok

Computer Science Faculty Research & Creative Works

Recent years saw the rapid development of peer-topeer (P2P) networks in a great variety of applications. However, similarity-based k-nearest-neighbor retrieval (k-NN) is still a challenging task in P2P networks due to the multiple constraints such as the dynamic topologies and the unpredictable data updates. Caching is an attractive solution that reduces network traffic and hence could remedy the technological constraints of P2P networks. However, traditional caching techniques have some major shortcomings that make them unsuitable for similarity search, such as the lack of semantic locality representation and the rigidness of exact matching on data objects. To facilitate the efficient similarity …

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Practical Experiences In Using Model-Driven Engineering To Develop Trustworthy Computing Systems, Thomas Weigert, Frank Weil Jan 2006

Practical Experiences In Using Model-Driven Engineering To Develop Trustworthy Computing Systems, Thomas Weigert, Frank Weil

Computer Science Faculty Research & Creative Works

In this paper, we describe how Motorola has deployed model-driven engineering in product development, in particular for the development of trustworthy and highly reliable telecommunications systems, and outline the benefits obtained. Model-driven engineering has dramatically increased both the quality and the reliability of software developed in our organization, as well as the productivity of our software engineers. Our experience demonstrates that model-driven engineering significantly improves the development process for trustworthy computing systems.

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Effect Of Amplification On Conductance Distribution Of A Disordered Waveguide, Alexey Yamilov, Hui Cao Jan 2006

Effect Of Amplification On Conductance Distribution Of A Disordered Waveguide, Alexey Yamilov, Hui Cao

Physics Faculty Research & Creative Works

Introduction of optical gain in a disordered system results in enhanced fluctuations [F(2)=var(g-tilde)/2] of the dimensionless conductance g-tilde, similar to the effect of Anderson localization in a passive medium. Using numerical simulations we demonstrate that, despite such qualitative similarity, the whole distribution of the conductance of amplifying random media is drastically different from that of a passive system with the same value of F(2).

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Kinematically Complete Experiment On Transfer Excitation In Intermediate-Energy P + He Collisions, Ahmad Hasan, B. Tooke, M. Zapukhlyak, T. Kirchner, Michael Schulz Jan 2006

Kinematically Complete Experiment On Transfer Excitation In Intermediate-Energy P + He Collisions, Ahmad Hasan, B. Tooke, M. Zapukhlyak, T. Kirchner, Michael Schulz

Physics Faculty Research & Creative Works

We have performed a kinematically complete experiment on transfer excitation in intermediate-energy proton-helium collisions. The differential cross sections were compared to double excitation data and a nonperturbative time-dependent calculation. This comparison reveals the importance of dynamic couplings between the motion of the heavy nuclei and electronic transitions and/or electron-electron correlation effects.

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Echo State Networks For Determining Harmonic Contributions From Nonlinear Loads, Joy Mazumdar, Ganesh K. Venayagamoorthy, Frank C. Lambert, Ronald G. Harley Jan 2006

Echo State Networks For Determining Harmonic Contributions From Nonlinear Loads, Joy Mazumdar, Ganesh K. Venayagamoorthy, Frank C. Lambert, Ronald G. Harley

Electrical and Computer Engineering Faculty Research & Creative Works

This paper investigates the application of a new kind of recurrent neural network called Echo State Networks (ESNs) for the problem of measuring the actual amount of harmonic current injected into a power network by a nonlinear load. The interaction between loads connected to a point of common coupling (PCC) is a highly dynamic process. The determination of true harmonic current injection by individual loads is further complicated by the fact that the supply voltage waveform at the PCC is distorted by other loads at the PCC or further upstream and is therefore rarely a pure sinusoid. Harmonics in a …

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Forecasting Using The Mahalanobis-Taguchi System In The Presence Of Collinearity, Elizabeth A. Cudney, Kenneth M. Ragsdell Jan 2006

Forecasting Using The Mahalanobis-Taguchi System In The Presence Of Collinearity, Elizabeth A. Cudney, Kenneth M. Ragsdell

Engineering Management and Systems Engineering Faculty Research & Creative Works

The Mahalanobis Taguchi System is a diagnosis and forecasting method for multivariate data. Mahalanobis distance is a measure based on correlations between the variables and different patterns that can be identified and analyzed with respect to a base or reference group. the issue of multicollinearity is not adequately addressed in the MTS method. in cases where strong relationships exist between variables, the correlation matrix becomes almost singular, and the inverse matrix is not accurate. Multicollinearity can be handled by utilizing the adjoint matrix of the correlation matrix and Gram-Schmidt orthogonalization. This paper presents a case study of the MTS methodology …

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Intentional Islanding And Adaptive Load Shedding To Avoid Cascading Outages, Badrul H. Chowdhury, H. Manjari Dola Jan 2006

Intentional Islanding And Adaptive Load Shedding To Avoid Cascading Outages, Badrul H. Chowdhury, H. Manjari Dola

Electrical and Computer Engineering Faculty Research & Creative Works

Predetermined islanding scenarios along with automated load shedding schemes are applied once a prospective cascading outage condition is predicted. If required, additional distributed generation at specified locations in the system is also determined. The choice of different islands along with loads to be shed is then made available to the operator so as to be armed for action in case the system security is compromised. Determination of line outages that lead to disastrous consequences, intentional islanding schemes, and load shedding schemes have been explored individually. A plan integrating these defense mechanisms coupled with the possibility of using distributed generation where …

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Electrochemical Deposition And Characterization Of Fe₃O₄ Films Produced By The Reduction Of Fe(Iii)-Triethanolamine, Hiten M. Kothari, Elizabeth A. Kulp, Steven J. Limmer, Philippe Poizot, Eric W. Bohannan, Jay A. Switzer Jan 2006

Electrochemical Deposition And Characterization Of Fe₃O₄ Films Produced By The Reduction Of Fe(Iii)-Triethanolamine, Hiten M. Kothari, Elizabeth A. Kulp, Steven J. Limmer, Philippe Poizot, Eric W. Bohannan, Jay A. Switzer

Chemistry Faculty Research & Creative Works

In this paper, we demonstrate that films of magnetite, Fe3O4, can be deposited by the electrochemical reduction of a Fe(III)-triethanolamine complex in aqueous alkaline solution. the films were deposited with a columnar microstructure and a [100] preferred orientation on stainless steel substrates. In-plane electrical transport and magnetoresistance measurements were performed on the films after they were stripped off onto glass substrates. the resistance of the films was dependent on the oxygen partial pressure. We attribute the increase in resistance in O2 and the decrease in resistance in Ar to the oxidation and reduction of grain …

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Molecular Mass And Dynamics Of Poly(Methyl Acrylate) In The Glass Transition Region, Burak Metin, Frank D. Blum Jan 2006

Molecular Mass And Dynamics Of Poly(Methyl Acrylate) In The Glass Transition Region, Burak Metin, Frank D. Blum

Chemistry Faculty Research & Creative Works

The segmental dynamics of bulk poly(methyl acrylate) (PMA) were studied as a function of molecular mass in the glass-transition region using 2H NMR and modulated differential scanning calorimetry (MDSC). Quadrupole-echo 2H NMR spectra were obtained for four samples of methyl-deuterated PMA-d3 with different molecular masses. The resulting spectra were fit using superpositions of simulated spectra generated from the MXQET simulation program, based on a model incorporating nearest-neighbor jumps from positions on the vertices of a truncated icosahedron (soccer-ball shape). The lower molecular-mass samples, influenced by the presence of more chain ends, showed more heterogeneity (broader distribution) and lower glass transitions …

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Segmental Mobility Of Chain Ends In Poly(Methyl Acrylate)-D3, Burak Metin, Frank D. Blum Jan 2006

Segmental Mobility Of Chain Ends In Poly(Methyl Acrylate)-D3, Burak Metin, Frank D. Blum

Chemistry Faculty Research & Creative Works

Better control of polymeric materials can be achieved with a thorough understanding of the dynamics of their constituents. In the present study, we consider polymer chains as composed of chain middles and chain ends. Even though chain ends do not comprise much of the sample by mass, they may play a crucial role in the ultimate properties of the polymers. Although chain ends have been assigned a higher mobility, as compared to chain middles, there have not been a large number of experimental studies that directly probe their mobility. Among those, the studies of Kitahara et al.1 and Miwa et …

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Neural Network-Based Output Feedback Controller For Lean Operation Of Spark Ignition Engines, Brian C. Kaul, Jagannathan Sarangapani, J. A. Drallmeier, Jonathan B. Vance, Pingan He Jan 2006

Neural Network-Based Output Feedback Controller For Lean Operation Of Spark Ignition Engines, Brian C. Kaul, Jagannathan Sarangapani, J. A. Drallmeier, Jonathan B. Vance, Pingan He

Electrical and Computer Engineering Faculty Research & Creative Works

Spark ignition (SI) engines running at very lean conditions demonstrate significant nonlinear behavior by exhibiting cycle-to-cycle dispersion of heat release even though such operation can significantly reduce NOx emissions and improve fuel efficiency by as much as 5-10%. A suite of neural network (NN) controller without and with reinforcement learning employing output feedback has shown ability to reduce the nonlinear cyclic dispersion observed under lean operating conditions. The neural network controllers consists of three NN: a) A NN observer to estimate the states of the engine such as total fuel and air; b) a second NN for generating virtual input; …

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Segmental Dynamics In Poly(Methyl Acrylate) On Silica: Molecular-Mass Effects, Burak Metin, Frank D. Blum Jan 2006

Segmental Dynamics In Poly(Methyl Acrylate) On Silica: Molecular-Mass Effects, Burak Metin, Frank D. Blum

Chemistry Faculty Research & Creative Works

The effect of molecular mass on the segmental dynamics of poly(methyl acrylate) (PMA) adsorbed on silica was studied using deuterium quadrupole-echo nuclear magnetic resonance (NMR) and modulated differential scanning calorimetry. Samples adsorbed on silica (all about 1.5 mg PMA/m2 silica) were shown to have more restricted segmental mobility, and higher Tg's, than the corresponding bulk PMA samples. Around the glass-transition region, adsorbed samples exhibited segmental mobility, which could be classified as heterogeneous due to a superposition of more-mobile and less-mobile components present in the deuterium NMR spectra. This heterogeneity was consistent with a motional gradient with more-mobile segments near the …

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Novel Sum-Of-Sinusoids Simulation Models For Rayleigh And Rician Fading Channels, Chengshan Xiao, Y. Rosa Zheng, N. C. Beaulieu Jan 2006

Novel Sum-Of-Sinusoids Simulation Models For Rayleigh And Rician Fading Channels, Chengshan Xiao, Y. Rosa Zheng, N. C. Beaulieu

Electrical and Computer Engineering Faculty Research & Creative Works

The statistical properties of Clarke's fading model with a finite number of sinusoids are analyzed, and an improved reference model is proposed for the simulation of Rayleigh fading channels. A novel statistical simulation model for Rician fading channels is examined. The new Rician fading simulation model employs a zero-mean stochastic sinusoid as the specular (line-of-sight) component, in contrast to existing Rician fading simulators that utilize a non-zero deterministic specular component. The statistical properties of the proposed Rician fading simulation model are analyzed in detail. It is shown that the probability density function of the Rician fading phase is not only …

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Decentralized Power Control With Implementation For Rfid Networks, Kainan Cha, Anil Ramachandran, David Pommerenke, Jagannathan Sarangapani Jan 2006

Decentralized Power Control With Implementation For Rfid Networks, Kainan Cha, Anil Ramachandran, David Pommerenke, Jagannathan Sarangapani

Electrical and Computer Engineering Faculty Research & Creative Works

In radio frequency identification (RFID) systems, the detection range and read rates will suffer from interference among high power reading devices. This problem grows severely and degrades system performance in dense RFID networks. In this paper, we investigate a suite of feasible power control schemes to ensure overall coverage area of the system while maintaining a desired read rate. The power control scheme and MAC protocol dynamically adjusts the RFID reader power output in response to the interference level seen locally during tag reading for an acceptable signal-to-noise ratio (SNR). We present novel distributed adaptive power control (DAPC) and probabilistic …

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Design And Implementation Of A Storage Management Method For Content Distribution, Chang-Soo Kim, Yu-Hyeon Bak, Sang-Min Woo, Won-Jae Lee, Nunm-Ok Gee, Hag-Young Kim Jan 2006

Design And Implementation Of A Storage Management Method For Content Distribution, Chang-Soo Kim, Yu-Hyeon Bak, Sang-Min Woo, Won-Jae Lee, Nunm-Ok Gee, Hag-Young Kim

Electrical and Computer Engineering Faculty Research & Creative Works

The SMART system is a special purpose server developed by ETRI and designed for efficient streaming services over high speed networks. The SMART server has one or more special purpose NS (Network-Storage) card. The NS card has several disks that store multimedia contents. However all of the multimedia contents to be serviced cannot be stored at the server. In this paper, we will describe the storage management mechanism in design and implementation aspects. With this storage management mechanism, the SMART server can provide effectiveness in managing storage and distributing some contents from a source station to streaming service servers.

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Fault-Tolerant Control For Sssc Using Neural Networks And Pso, Wei Qiao, Ganesh K. Venayagamoorthy, Ronald G. Harley Jan 2006

Fault-Tolerant Control For Sssc Using Neural Networks And Pso, Wei Qiao, Ganesh K. Venayagamoorthy, Ronald G. Harley

Electrical and Computer Engineering Faculty Research & Creative Works

No abstract provided.

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Gene Expression Data For Dlbcl Cancer Survival Prediction With A Combination Of Machine Learning Technologies, Rui Xu, Xindi Cai, Donald C. Wunsch Jan 2006

Gene Expression Data For Dlbcl Cancer Survival Prediction With A Combination Of Machine Learning Technologies, Rui Xu, Xindi Cai, Donald C. Wunsch

Electrical and Computer Engineering Faculty Research & Creative Works

Gene expression profiles have become an important and promising way for cancer prognosis and treatment. In addition to their application in cancer class prediction and discovery, gene expression data can be used for the prediction of patient survival. Here, we use particle swarm optimization (PSO) to address one of the major challenges in gene expression data analysis, the curse of dimensionality, in order to discriminate high risk patients from low risk patients. A discrete binary version of PSO is used for gene selection and dimensionality reduction, and a probabilistic neural network (PNN) is implemented as the classifier. The experimental results …

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