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Full-Text Articles in Engineering

Least Squares Support Vector Machine Based Classification Of Abnormalities In Brain Mr Images, S. Thamarai Selvi, D. Selvathi, R. Ramkumar, Henry Selvaraj Mar 2006

Least Squares Support Vector Machine Based Classification Of Abnormalities In Brain Mr Images, S. Thamarai Selvi, D. Selvathi, R. Ramkumar, Henry Selvaraj

Electrical & Computer Engineering Faculty Research

The manual interpretation of MRI slices based on visual examination by radiologist/physician may lead to missing diagnosis when a large number of MRIs are analyzed. To avoid the human error, an automated intelligent classification system is proposed. This research paper proposes an intelligent classification technique to the problem of classifying four types of brain abnormalities viz. Metastases, Meningiomas, Gliomas, and Astrocytomas. The abnormalities are classified based on Two/Three/ Four class classification using statistical and textural features. In this work, classification techniques based on Least Squares Support Vector Machine (LS-SVM) using textural features computed from the MR images of patient are …


On Innovative Methods Of Induction Motor Interturn And Broken-Bar Fault Diagnostics, Behrooz Mirafzal, Nabeel Demerdash Mar 2006

On Innovative Methods Of Induction Motor Interturn And Broken-Bar Fault Diagnostics, Behrooz Mirafzal, Nabeel Demerdash

Electrical and Computer Engineering Faculty Research and Publications

A fault indicator, the so-called swing angle, for broken-bar and interturn faults is investigated in this paper. This fault indicator is based on the rotating magnetic-field pendulous-oscillation concept in faulty squirrel-cage induction motors. Using the "swing-angle indicator," it will be demonstrated here that an interturn fault can be detected even in the presence of machine manufacturing imperfections. Meanwhile, a broken-bar fault can be detected under both direct-line and PWM excitations, even under the more difficult condition of partial-load levels. These two conditions of partial load and motor manufacturing imperfections, which are considered as difficult situations for fault detection, are investigated …


A Gradient-Based Optimum Block Adaptation Ica Technique For Interference Suppression In Highly Dynamic Communication Channels, Wasfy B. Mikhael, Tianyu Yang Feb 2006

A Gradient-Based Optimum Block Adaptation Ica Technique For Interference Suppression In Highly Dynamic Communication Channels, Wasfy B. Mikhael, Tianyu Yang

Department of Electrical Engineering and Computer Science - Daytona Beach

The fast fixed-point independent component analysis (ICA) algorithm has been widely used in various applications because of its fast convergence and superior performance. However, in a highly dynamic environment, real-time adaptation is necessary to track the variations of the mixing matrix. In this scenario, the gradient-based online learning algorithm performs better, but its convergence is slow, and depends on a proper choice of convergence factor. This paper develops a gradient-based optimum block adaptive ICA algorithm (OBA/ICA) that combines the advantages of the two algorithms. Simulation results for telecommunication applications indicate that the resulting performance is superior under time-varying conditions, which …


Statistical Correlation Of Gain And Buildup Time In Apds And Its Effects On Receiver Performance, Peng Sun, Majeed M. Hayat, Bahaa E.A. Saleh, Malvin Carl Teich Feb 2006

Statistical Correlation Of Gain And Buildup Time In Apds And Its Effects On Receiver Performance, Peng Sun, Majeed M. Hayat, Bahaa E.A. Saleh, Malvin Carl Teich

Electrical and Computer Engineering Faculty Research and Publications

This paper reports a novel recurrence theory that enables us to calculate the exact joint probability density function (pdf) of the random gain and the random avalanche buildup time in avalanche photodiodes (APDs) including the effect of dead space. Such calculations reveal a strong statistical correlation between the gain and the buildup time for all widths of the multiplication region. To facilitate the calculation of the photocurrent statistics in the presence of this correlation, the impulse-response function of the APD is approximately modeled by a function of time whose prespecified shape is appropriately parameterized by two random variables: the gain …


Adaptive Evolution Of Chloroplast Genome Structure Inferred Using A Parametric Bootstrap Approach, Liying Cui, Jim Leebens-Mack, Li-San Wang, Jijun Tang, Linda Rymarquis, David B. Stern, Claude W. Depamphilis Feb 2006

Adaptive Evolution Of Chloroplast Genome Structure Inferred Using A Parametric Bootstrap Approach, Liying Cui, Jim Leebens-Mack, Li-San Wang, Jijun Tang, Linda Rymarquis, David B. Stern, Claude W. Depamphilis

Faculty Publications

Background
Genome rearrangements influence gene order and configuration of gene clusters in all genomes. Most land plant chloroplast DNAs (cpDNAs) share a highly conserved gene content and with notable exceptions, a largely co-linear gene order. Conserved gene orders may reflect a slow intrinsic rate of neutral chromosomal rearrangements, or selective constraint. It is unknown to what extent observed changes in gene order are random or adaptive. We investigate the influence of natural selection on gene order in association with increased rate of chromosomal rearrangement. We use a novel parametric bootstrap approach to test if directional selection is responsible for the …


Characterization Of Metal And Metal Alloy Films As Contact Materials In Mems Switches, Hyukjae Lee, Ronald A. Coutu Jr., Shankar Mall, Kevin D. Leedy Feb 2006

Characterization Of Metal And Metal Alloy Films As Contact Materials In Mems Switches, Hyukjae Lee, Ronald A. Coutu Jr., Shankar Mall, Kevin D. Leedy

Electrical and Computer Engineering Faculty Research and Publications

This study presents a basic step toward the selection methodology of electric contact materials for microelectromechanical systems (MEMS) metal contact switches. This involves the interrelationship between two important parameters, resistivity and hardness, since they provide the guidelines and assessment of contact resistance, wear, deformation and adhesion characteristics of MEMS switches. For this purpose, thin film alloys of three noble metals, platinum (Pt), rhodium (Rh) and ruthenium (Ru) with gold (Au), were investigated. The interrelationship between resistivity and hardness was established for three levels of alloying of these metals with gold. Thin films of gold (Au), platinum (Pt), ruthenium (Rh) and …


Images With Uncertainty: Efficient Algorithms For Shift, Rotation, Scaling, And Registration, And Their Applications To Geosciences, C. G. Schiek, Roberto Araiza, Jose M. Hurtado, A. A. Velazco, Vladik Kreinovich, V. Sinyanski Feb 2006

Images With Uncertainty: Efficient Algorithms For Shift, Rotation, Scaling, And Registration, And Their Applications To Geosciences, C. G. Schiek, Roberto Araiza, Jose M. Hurtado, A. A. Velazco, Vladik Kreinovich, V. Sinyanski

Departmental Technical Reports (CS)

In geosciences, we often need to combine two or images of the same area:

in data fusion, we must combine, e.g., data from satellite images with a radar image

in analyzing the effect of an earthquake, we must compare the before and after images, etc.

Compared images are often obtained from slightly different angles, from a slightly different position. Therefore, in order to compare these images, we must register them, i.e., find the shift, rotation, and scaling after which these images match the best, and then apply these transformations to the original images.

There exist efficient algorithms for registration and …


Ellipsoids And Ellipsoid-Shaped Fuzzy Sets As Natural Multi-Variate Generalization Of Intervals And Fuzzy Numbers: How To Elicit Them From Users, And How To Use Them In Data Processing, Vladik Kreinovich, Jan Beck, Hung T. Nguyen Feb 2006

Ellipsoids And Ellipsoid-Shaped Fuzzy Sets As Natural Multi-Variate Generalization Of Intervals And Fuzzy Numbers: How To Elicit Them From Users, And How To Use Them In Data Processing, Vladik Kreinovich, Jan Beck, Hung T. Nguyen

Departmental Technical Reports (CS)

In this paper, we show that ellipsoids are natural multi-variate generalization of intervals and ellipsoid-shaped fuzzy sets are a natural generalization of fuzzy numbers. We explain how to elicit them from users, and how to use them in data processing.


Detecting Outliers Under Interval Uncertainty: A New Algorithm Based On Constraint Satisfaction, Evgeny Dantsin, Alexander Wolpert, Martine Ceberio, Gang Xiang, Vladik Kreinovich Feb 2006

Detecting Outliers Under Interval Uncertainty: A New Algorithm Based On Constraint Satisfaction, Evgeny Dantsin, Alexander Wolpert, Martine Ceberio, Gang Xiang, Vladik Kreinovich

Departmental Technical Reports (CS)

In many application areas, it is important to detect outliers. The traditional engineering approach to outlier detection is that we start with some "normal" values x1,...,xn, compute the sample average E, the sample standard deviation sigma, and then mark a value x as an outlier if x is outside the k0-sigma interval [E-k0*sigma,E+k0*sigma] (for some pre-selected parameter k0). In real life, we often have only interval ranges [xi-,xi+] for the normal values x1,...,xn. In this case, we only have intervals of possible values for the bounds L=E-k0*sigma and U=E+k0*sigma. We can therefore identify outliers as values that are outside all …


Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 22, Number 5, February 2006, College Of Engineering And Computer Science, Wright State University Feb 2006

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 22, Number 5, February 2006, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

A six page newsletter created by the Wright State University College of Engineering and Computer Science that addresses the current affairs of the college.


An Ontological Approach For Building A Pattern Language And A Pattern Language Management Tool, Reaham Osama Badr Feb 2006

An Ontological Approach For Building A Pattern Language And A Pattern Language Management Tool, Reaham Osama Badr

Archived Theses and Dissertations

The Study of patterns and pattern inter relationships has become a recent issue tackled by many researchers. Although not many pattern languages exist yet, the importance of their existence is clearly noted. Authors argue that connecting related patterns using the relationships existing between them, gives them an additional value over individual patterns.

The main issues faced when dealing with pattern languages is how to build these languages and how to mange them afterwards. In this research work, an ontological approach is used to present a methodology for building a pattern language. This methodology is presented in the form of a …


Reputed Authenticated Routing For Ad Hoc Networks Protocol (Reputed-Aran), Abdalla Ahmed Fekry Mahmoud Feb 2006

Reputed Authenticated Routing For Ad Hoc Networks Protocol (Reputed-Aran), Abdalla Ahmed Fekry Mahmoud

Archived Theses and Dissertations

A mobile ad hoc network (MANET) is a spontaneous network that can be established with no fixed infrastructure. This means that all its nodes behave as routers and take part in its discovery and maintenance of routes to other nodes in the network. Its routing protocol has to be able to cope with the new challenges that a MANET creates such as nodes mobility, security maintenance, quality of service, limited bandwidth and limited power supply. These challenges set new demands on MANET routing protocols. With the increasing interest in MANETs, there has been a greater focus on the subject of …


Detection Efficiencies And Generalized Breakdown Probabilities For Nanosecond-Gated Near Infrared Single-Photon Avalanche Photodiodes, David A. Ramirez, Majeed M. Hayat, Gauri Karve, Joe C. Campbell, Sergio N. Torres, Bahaa E.A. Saleh, Malvin Carl Teich Feb 2006

Detection Efficiencies And Generalized Breakdown Probabilities For Nanosecond-Gated Near Infrared Single-Photon Avalanche Photodiodes, David A. Ramirez, Majeed M. Hayat, Gauri Karve, Joe C. Campbell, Sergio N. Torres, Bahaa E.A. Saleh, Malvin Carl Teich

Electrical and Computer Engineering Faculty Research and Publications

A rigorous model is developed for determining single-photon quantum efficiency (SPQE) of single-photon avalanche photodiodes (SPADs) with simple or heterojunction multiplication regions. The analysis assumes nanosecond gated-mode operation of the SPADs and that band-to-band tunneling of carriers is the dominant source of dark current in the multiplication region. The model is then utilized to optimize the SPQE as a function of the applied voltage, for a given operating temperature and multiplication-region structure and material. The model can be applied to SPADs with In/sub 0.52/Al/sub 0.48/As or InP multiplication regions as well as In/sub 0.52/Al/sub 0.48/As--InP heterojunction multiplication regions for wavelengths …


Design And Stability Analysis Of High Performance Packet Switches, Zhen Guo Jan 2006

Design And Stability Analysis Of High Performance Packet Switches, Zhen Guo

Dissertations

With the rapid development of optical interconnection technology, high-performance packet switches are required to resolve contentions in a fast manner to satisfy the demand for high throughput and high speed rates. Combined input-crosspoint buffered (CICB) switches are an alternative to input-buffered (IB) packet switches to provide high-performance switching and to relax arbitration timing for packet switches with high-speed ports.

A maximum weight matching (MWM) scheme can provide 100% throughput under admissible traffic for lB switches. However, the high complexity of MWM prohibits its implementation in high-speed switches. In this dissertation, a feedback-based arbitration scheme for CICB switches is studied, where …


Probabilistic Approaches To The Design Of Wireless Ad Hoc And Sensor Networks, Zhen Guo Jan 2006

Probabilistic Approaches To The Design Of Wireless Ad Hoc And Sensor Networks, Zhen Guo

Dissertations

The emerging wireless technologies has made ubiquitous wireless access a reality and enabled wireless systems to support a large variety of applications. Since the wireless self-configuring networks do not require infrastructure and promise greater flexibility and better coverage, wireless ad hoc and sensor networks have been under intensive research. It is believed that wireless ad hoc and sensor networks can become as important as the Internet. Just as the Internet allows access to digital information anywhere, ad hoc and sensor networks will provide remote interaction with the physical world.

Dynamics of the object distribution is one of the most important …


Multilevel Adaptive Security System, Hongwei Li Jan 2006

Multilevel Adaptive Security System, Hongwei Li

Dissertations

Recent trends show increased demand for content-rich media such as images, videos and text in ad-hoc communication. Since such content often tends to be private, sensitive, or paid for, there exists a requirement for securing such information over resource constrained ad hoc networks. In this work, traditional data security mechanisms, existing ad hoc secure routing protocols and multilevel security are first reviewed. Then a new system, called the Multilevel Adaptive Security System, which incorporates the multilevel security concept at both the application layer and the network layer, is proposed to provide adaptive security services for data and routing processes.

MLASS …


Design And Resource Management Of Reconfigurable Multiprocessors For Data-Parallel Applications, Xiaofang Wang Jan 2006

Design And Resource Management Of Reconfigurable Multiprocessors For Data-Parallel Applications, Xiaofang Wang

Dissertations

FPGA (Field-Programmable Gate Array)-based custom reconfigurable computing machines have established themselves as low-cost and low-risk alternatives to ASIC (Application-Specific Integrated Circuit) implementations and general-purpose microprocessors in accelerating a wide range of computation-intensive applications. Most often they are Application Specific Programmable Circuiits (ASPCs), which are developer programmable instead of user programmable. The major disadvantages of ASPCs are minimal programmability, and significant time and energy overheads caused by required hardware reconfiguration when the problem size outnumbers the available reconfigurable resources; these problems are expected to become more serious with increases in the FPGA chip size. On the other hand, dominant high-performance computing …


Hfo2 As Gate Dielectric On Si And Ge Substrate, Reenu Garg Jan 2006

Hfo2 As Gate Dielectric On Si And Ge Substrate, Reenu Garg

Dissertations

Hafnium oxide HfO2 has been considered as an alternative to silicon dioxide SiO2 in future nano-scale complementary metal-oxide-semiconductor (CMOS) devices since it provides the required capacitance at the reduced device size because of its high dielectric constant. HfO2 films are currently deposited by various techniques. Many of them require high temperature annealing that can impact device performance and reliability.

In this research, electrical characteristics of capacitors with HfO2 as gate dielectric deposited by standard thermal evaporation and e-beam evaporation on Si and Ge substrates were investigated. The dielectric constant of HfO2 deposited by thermal evaporation …


Online Clustering With Single-Pass Topology Based Fuzzy Clustering Algorithm, Abhishek Jaiantilal Jan 2006

Online Clustering With Single-Pass Topology Based Fuzzy Clustering Algorithm, Abhishek Jaiantilal

Theses

Online clustering is of significant interest for real-time data analysis. Generic offline clustering methods such as K-Means, C-Means and others are computationally expensive. The computational burden of these methods increases non-linearly with the size of the data set. In addition these methods usually require a good amount of supervised knowledge yielding a non-unique solution. For real-time data analysis, there is an important tradeoff between accuracy and computational efficiency. An unsupervised one-pass clustering method that efficiently adapts to data distribution and evaluation is proposed. This method, Topology-Based Fuzzy Clustering (TFC), uses the topology of data to discover clusters. TFC uses the …


New Hybrid Automatic Repeat Request (Harq) Combining With Space Time Block Coding (Stbc) In Invariant And Variant Fading Channel, Guillem Ernest Malagarriga Vilella Jan 2006

New Hybrid Automatic Repeat Request (Harq) Combining With Space Time Block Coding (Stbc) In Invariant And Variant Fading Channel, Guillem Ernest Malagarriga Vilella

Theses

Hybrid Automatic Repeat reQuest (HARQ) combining for space time block coding Multiple Input Multiple Output (MIMO) system consisting of N transmit antennas and M receive antennas (NxM) in a time invariant channel and in a time varying channel is proposed and its performance is analyzed. Based on the measured channel matrix, the receiver chooses the best retransmission order and communicated it to the transmitter.

The scheme, where this algorithm is performed, is a combination of a precombining HARQ scheme and the Multiple Alamouti Space-Time Block Coding (MASTBC), which is suitable for more than 2 transmit antennas. The combination of this …


Spectrophotometer, Ellipsometer, Polarmeter And The Like Systems, John A. Woollam, Steven E. Green, Ping He, Blaine D. Johs, Craig M. Herzinger, Galen L. Pfeiffer, Brian D. Guenther, Martin M. Liphardt Jan 2006

Spectrophotometer, Ellipsometer, Polarmeter And The Like Systems, John A. Woollam, Steven E. Green, Ping He, Blaine D. Johs, Craig M. Herzinger, Galen L. Pfeiffer, Brian D. Guenther, Martin M. Liphardt

Department of Electrical and Computer Engineering: Faculty Publications

Disclosed are improvements in ellipsometer and the like systems capable of operating in the Vacuum-Ultra-Violet (VUV) to Near Infrared (NIR) wavelength range, and methodology of use.


The Utep Corpus Of Iraqi Arabic, Nigel Ward, David G. Novick, Salamah I. Salamah Jan 2006

The Utep Corpus Of Iraqi Arabic, Nigel Ward, David G. Novick, Salamah I. Salamah

Departmental Technical Reports (CS)

The rules governing turn-taking phenomena are not well understood in general and almost completely undocumented for Arabic. As the first step to modeling these phenomena, we have collected a small corpus of Iraqi Arabic spoken dialogs. The corpus is in three parts. Part A is 110 minutes of unstructured conversations. Parts B1 and B2 are 176 minutes of direction-giving dialogs, most including a greeting phase, a smalltalk phase, a request phase, and a direction-giving phase. Parts A and B1 were recorded with 13 native speakers of Iraqi Arabic, interacting in pairs. In Part B2 the direction-getter is an American with …


Mimo Communications In Ad Hoc Networks, Biao Chen, Michael J. Gans Jan 2006

Mimo Communications In Ad Hoc Networks, Biao Chen, Michael J. Gans

Electrical Engineering and Computer Science - All Scholarship

We study in this paper the network spectral efficiency in terms of bits/s/Hz of a MIMO (multiple-input multiple output) ad hoc network with K simultaneous communicating transmitter-receiver pairs. Assume that each transmitter is equipped with t antennas and each receiver implements single user detection. We show that in the absence of channel state information (CSI) at the transmitters, the asymptotic network spectral efficiency is limited by r nats/s/Hz as K -> ∞ and is independent of t and the transmit power. With CSI corresponding to the desired receiver available at the transmitter, we demonstrate that the asymptotic spectral efficiency is …


Ontological Implications Of The Levels Of Conceptual Interoperability Model, Andreas Tolk, Charles D. Turnitsa, Saikou Y. Diallo Jan 2006

Ontological Implications Of The Levels Of Conceptual Interoperability Model, Andreas Tolk, Charles D. Turnitsa, Saikou Y. Diallo

Computational Modeling & Simulation Engineering Faculty Publications

The Levels of Conceptual Interoperability Model (LCIM) was developed to cope with the different layers of interoperation of modeling & simulation applications. It introduced technical, syntactic, semantic, pragmatic, dynamic, and conceptual layers of interoperation and showed how they are related to the ideas of integratability, interoperability, and composability. This paper will be presented in the invited session "Ontology Driven Interoperability for Agile Applications using Information Systems: Requirements and Applications for Agent Mediated Decision Support" at WMSCI 2006.


Modeling Correlation And Dependence Among Intervals, Scott Ferson, Vladik Kreinovich Jan 2006

Modeling Correlation And Dependence Among Intervals, Scott Ferson, Vladik Kreinovich

Departmental Technical Reports (CS)

This note introduces the notion of dependence among intervals to account for observed or theoretical constraints on the relationships among uncertain inputs in mathematical calculations. We define dependence as any restriction on the possible pairings of values within respective intervals and define nondependence as the degenerate case of no restrictions (which we carefully distinguish from independence in probability theory). Traditional interval calculations assume nondependence, but alternative assumptions are possible, including several which might be practical in engineering settings that would lead to tighter enclosures on arithmetic functions of intervals. We give best possible formulas for addition of intervals under several …


Interval-Based Robust Statistical Techniques For Non-Negative Convex Functions With Application To Timing Analysis Of Computer Chips, Michael Orshansky, Wei-Shen Wang, Gang Xiang, Vladik Kreinovich Jan 2006

Interval-Based Robust Statistical Techniques For Non-Negative Convex Functions With Application To Timing Analysis Of Computer Chips, Michael Orshansky, Wei-Shen Wang, Gang Xiang, Vladik Kreinovich

Departmental Technical Reports (CS)

In chip design, one of the main objectives is to decrease its clock cycle; however, the existing approaches to timing analysis under uncertainty are based on fundamentally restrictive assumptions. Statistical timing analysis techniques assume that the full probabilistic distribution of timing uncertainty is available; in reality, the complete probabilistic distribution information is often unavailable. Additionally, the existing alternative of treating uncertainty as interval-based, or affine, is limited since it cannot handle probabilistic information in principle. In this paper, a fundamentally new paradigm for timing uncertainty description is proposed as a way to consistently and rigorously handle partially available descriptions of …


On The Functional Form Of Convex Underestimators For Twice Continuously Differentiable Functions, Chirstodoulos A. Floudas, Vladik Kreinovich Jan 2006

On The Functional Form Of Convex Underestimators For Twice Continuously Differentiable Functions, Chirstodoulos A. Floudas, Vladik Kreinovich

Departmental Technical Reports (CS)

The optimal functional form of convex underestimators for general twice continuously differentiable functions is of major importance in deterministic global optimization. In this paper, we provide new theoretical results that address the classes of optimal functional forms for the convex underestimators. These are derived based on the properties of shift-invariance and sign-invariance.


Free Roaming: A System For Ubiquitous Computing, Huanjin Liu Jan 2006

Free Roaming: A System For Ubiquitous Computing, Huanjin Liu

Theses Digitization Project

Based on the Umbilical Cord system, this project enriches the Ubiquitous Computing system with a Free Roaming system. This Free Roaming consists of a distributed authentication system, a data caching system and a communication system between them. It allows user to roam within this system and access his data everywhere. Together with the Umbilical Cord system, a Ubiquitous Computing system is functionally completed as a prototype, and is ready to be deployed into the Internet.


Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 22, Number 4, January 2006, College Of Engineering And Computer Science, Wright State University Jan 2006

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 22, Number 4, January 2006, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

A ten page newsletter created by the Wright State University College of Engineering and Computer Science that addresses the current affairs of the college.


Swarm Intelligence: Theoretical Proof That Empirical Techniques Are Optimal, Dmitry Iourinskiy, Scott A. Starks, Vladik Kreinovich, Stephen F. Smith Jan 2006

Swarm Intelligence: Theoretical Proof That Empirical Techniques Are Optimal, Dmitry Iourinskiy, Scott A. Starks, Vladik Kreinovich, Stephen F. Smith

Departmental Technical Reports (CS)

A natural way to distribute tasks between autonomous agents is to use swarm intelligence techniques, which simulate the way social insects (such as wasps) distribute tasks between themselves. In this paper, we theoretically prove that the corresponding successful biologically inspired formulas are indeed statistically optimal (in some reasonable sense).