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Full-Text Articles in Engineering

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 20, Number 8, June 2004, College Of Engineering And Computer Science, Wright State University Jun 2005

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 20, Number 8, June 2004, 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.


Which Fuzzy Logic Is The Best: Pragmatic Approach (And Its Theoretical Analysis), Vladik Kreinovich, Hung T. Nguyen Jun 2005

Which Fuzzy Logic Is The Best: Pragmatic Approach (And Its Theoretical Analysis), Vladik Kreinovich, Hung T. Nguyen

Departmental Technical Reports (CS)

In this position paper, we argue that when we are looking for the best fuzzy logic, we should specify in what sense the best, and that we get different fuzzy logics as ``the best'' depending on what optimality criterion we use.


Kolmogorov Complexity Leads To A Representation Theorem For Idempotent Probabilities (Sigma-Maxitive Measures), Vladik Kreinovich, Luc Longpre Jun 2005

Kolmogorov Complexity Leads To A Representation Theorem For Idempotent Probabilities (Sigma-Maxitive Measures), Vladik Kreinovich, Luc Longpre

Departmental Technical Reports (CS)

In many application areas, it is important to consider maxitive measures (idempotent probabilities), i.e., mappings m for which m(A U B)=max(m(A),m(B)). In his papers, J. H. Lutz has used Kolmogorov complexity to show that for constructively defined sets A, one maxitive measure - fractal dimension - can be represented as m(A)= sup{f(x): x in A}. We show that a similar representation is possible for an arbitrary maxitive measure.


If An Exact Interval Computation Problem Is Np-Hard, Then The Approximate Problem Is Also Np-Hard: A Meta-Result, Aline B. Loreto, Laira V. Toscani, Leila Robeiro, Dalcidio M. Claudio, Liara S. Leal, Luc Longpre, Vladik Kreinovich Jun 2005

If An Exact Interval Computation Problem Is Np-Hard, Then The Approximate Problem Is Also Np-Hard: A Meta-Result, Aline B. Loreto, Laira V. Toscani, Leila Robeiro, Dalcidio M. Claudio, Liara S. Leal, Luc Longpre, Vladik Kreinovich

Departmental Technical Reports (CS)

In interval computations, usually, once we prove that a problem of computing the exact range is NP-hard, then it later turns out that the problem of computing this range with a given accuracy is also NP-hard. In this paper, we provide a general explanation for this phenomenon.


Consortium Of Cise-Mii Funded Institutions: Initial Recommendations On Broadening Participation Of Hispanics, Ann Q. Gates Jun 2005

Consortium Of Cise-Mii Funded Institutions: Initial Recommendations On Broadening Participation Of Hispanics, Ann Q. Gates

Departmental Technical Reports (CS)

No abstract provided.


Kaluza-Klein 5d Ideas Made Fully Geometric, Scott A. Starks, Olga Kosheleva, Vladik Kreinovich Jun 2005

Kaluza-Klein 5d Ideas Made Fully Geometric, Scott A. Starks, Olga Kosheleva, Vladik Kreinovich

Departmental Technical Reports (CS)

After the 1916 success of General relativity that explained gravity by adding time as a fourth dimension, physicists have been trying to explain other physical fields by adding extra dimensions. In 1921, Kaluza and Klein has shown that under certain conditions like cylindricity (dg_{ij}/dx^5=0), the addition of the 5th dimension can explain the electromagnetic field. The problem with this approach is that while the model itself is geometric, conditions like cylindricity are not geometric. This problem was partly solved by Einstein and Bergman who proposed, in their 1938 paper, that the 5th dimension is compactified into a small circle S^1 …


Some Usability Issues And Research Priorities In Spoken Dialog Applications, Nigel Ward, Anais G. Rivera, Karen Ward, David G. Novick Jun 2005

Some Usability Issues And Research Priorities In Spoken Dialog Applications, Nigel Ward, Anais G. Rivera, Karen Ward, David G. Novick

Departmental Technical Reports (CS)

As a priority-setting exercise, we examined interactions between users and a simple spoken dialog system in comparison to interactions with a human operator. Based on analysis of the observed usability differences and their root causes we propose seven priority issues for spoken dialog systems research.


Computing Best-Possible Bounds For The Distribution Of A Sum Of Several Variables Is Np-Hard, Vladik Kreinovich, Scott Ferson Jun 2005

Computing Best-Possible Bounds For The Distribution Of A Sum Of Several Variables Is Np-Hard, Vladik Kreinovich, Scott Ferson

Departmental Technical Reports (CS)

In many real-life situations, we know the probability distribution of two random variables x1 and x2, but we have no information about the correlation between x1 and x2; what are the possible probability distributions for the sum x1+x2? This question was originally raised by A. N. Kolmogorov. Algorithms exist that provide best-possible bounds for the distribution of x1+x2; these algorithms have been implemented as a part of the efficient software for handling probabilistic uncertainty. A natural question is: what if we have several (n>2) variables with known distribution, we have no information about their correlation, and we are interested …


Why Product Of Probabilities (Masses) For Independent Events? A Remark, Vladik Kreinovich, Scott Ferson Jun 2005

Why Product Of Probabilities (Masses) For Independent Events? A Remark, Vladik Kreinovich, Scott Ferson

Departmental Technical Reports (CS)

For independent events A and B, the probability P(A&B) is equal to the product of the corresponding probabilities: P(A&B)=P(A)*P(B). It is well known that the product f(a,b)=a*b has the following property: once P(A1)+...+P(An)=1 and P(B1)+...+P(Bm)=1, the probabilities P(Ai&Bj)=f(P(Ai),P(Bj)) also add to 1: f(P(A1),P(B1))+...+f(P(An),P(Bm))=1. We prove that the product is the only function that satisfies this property, i.e., that if, vice versa, this property holds for some function f(a,b), then this function f is the product. This result provided an additional explanation of why for independent events, we multiply probabilities (or, in the Dempster-Shafer case, masses).

In this paper, we strengthen …


A Jbi Information Object Engineering Environment Utilizing Metadata Fragments For Refining Searches On Semantically-Related Object Types, Felicia N. Harlow Jun 2005

A Jbi Information Object Engineering Environment Utilizing Metadata Fragments For Refining Searches On Semantically-Related Object Types, Felicia N. Harlow

Theses and Dissertations

The Joint Battlespace Infosphere (JBI) architecture defines the Information Object (IO) as its basic unit of data. This research proposes an IO engineering methodology that will introduce componentized IO type development. This enhancement will improve the ability of JBI users to create and store IO type schemas, and query and subscribe to information objects, which may be semantically related by their inclusion of common metadata elements. Several parallel efforts are being explored to enable efficient storage and retrieval of IOs. Utilizing relational database access methods, applying a component-based IO type development concept, and exploiting XML inclusion mechanisms, this research improves …


Auto-Pipe: A Pipeline Design And Evaluation System, Mark A. Franklin, John Maschmeyer, Eric Tyson, James Buckley, Patrick Crowley Jun 2005

Auto-Pipe: A Pipeline Design And Evaluation System, Mark A. Franklin, John Maschmeyer, Eric Tyson, James Buckley, Patrick Crowley

All Computer Science and Engineering Research

Auto-Pipe is a tool that aids in the design, evaluation, and implementation of pipelined applications that are distributed across a set of heterogeneous devices including multiple processors and FPGAs. It has been developed to meet the needs arising in the domains of communications, computation on large datasets, and real time streaming data applications. In this paper, the Auto-Pipe design flow is introduced and two sample applications, developed for compatibility with the Auto-Pipe system, are presented. The sample applications are the Triple-DES encryption standard and a subset of the signal-processing pipeline for VERITAS, a high-energy gamma-ray astrophysics experiment. These applications are …


Motion Detection Using Randomized Methods, Howaida Mohamed Naguib Jun 2005

Motion Detection Using Randomized Methods, Howaida Mohamed Naguib

Archived Theses and Dissertations

The detection and recogni6on of a moving object in a sequence of time varying images proves to be a very important task in machine intelligence in general and computer vision in particular. Recently, parametric domain techniques have been successfully used with a number of variants. In such melhods, the image is transfonned into some parameter space and the motion detection process is applied in that space. A recent parametric domain is the Randomized Hough Transform (RHT) that uses random sampling mechanism in the image space, score accumulation in the parameter space, and bridge between them using a converging mapping. The …


Security Information Management With Frame-Based Attack Presentation And First-Order Reasoning, Wei Yan May 2005

Security Information Management With Frame-Based Attack Presentation And First-Order Reasoning, Wei Yan

Dissertations

Internet has grown by several orders of magnitude in recent years, and this growth has escalated the importance of computer security. Intrusion Detection System (IDS) is used to protect computer networks. However, the overwhelming flow of log data generated by IDS hamper security administrators from uncovering new insights and hidden attack scenarios. Security Information Management (SIM) is a new growing area of interest for intrusion detection. The research work in this dissertation explores the semantics of attack behaviors and designs Frame-based Attack Representation and First-order logic Automatic Reasoning (FAR-FAR) using linguistics and First-order Logic (FOL) based approaches. Techniques based on …


A Versatile Programming Model For Dynamic Task Scheduling On Cluster Computers, Dejiang Jin May 2005

A Versatile Programming Model For Dynamic Task Scheduling On Cluster Computers, Dejiang Jin

Dissertations

This dissertation studies the development of application programs for parallel and distributed computer systems, especially PC clusters. A methodology is proposed to increase the efficiency of code development, the productivity of programmers and enhance performance of executing the developed programs on PC clusters while facilitating improvement of scalability and code portability of these programs. A new programming model, named the Super-Programming Model (SPM), is created. Programs are developed assuming an instruction set architecture comprised of SuperInstructions (SIs). SPM models the target system as a large Virtual Machine (VM); VM contains functional units which are underlain with sub-computer systems and SIs …


Tcp Performance Enhancement In Wireless Networks Via Adaptive Congestion Control And Active Queue Management, Kai Xu May 2005

Tcp Performance Enhancement In Wireless Networks Via Adaptive Congestion Control And Active Queue Management, Kai Xu

Dissertations

The transmission control protocol (TCP) exhibits poor performance when used in error-prone wireless networks. Remedy to this problem has been an active research area. However, a widely accepted and adopted solution is yet to emerge. Difficulties of an acceptable solution lie in the areas of compatibility, scalability, computational complexity and the involvement of intermediate routers and switches.

This dissertation rexriews the current start-of-the-art solutions to TCP performance enhancement, and pursues an end-to-end solution framework to the problem. The most noticeable cause of the performance degradation of TCP in wireless networks is the higher packet loss rate as compared to that …


Cluster-Based Wireless Mobile Ad-Hoc Network Security, Mandur Bajra Bajracharya May 2005

Cluster-Based Wireless Mobile Ad-Hoc Network Security, Mandur Bajra Bajracharya

Theses

A wireless ad-hoc network is a cooperative communication network deployed with a specific purpose. It is characterized by dynamically changing topology with no fixed infrastructure which exhibits a perfectly vulnerable state for a number of different kinds of attacks.

This thesis proposes a novel technique of achieving security in wireless mobile ad hoc networks by integrating a simple clustering and a voting mechanism together. The purpose of forming a cluster is to facilitate security in the network and the voting is performed to support the decision making process in the cluster. A procedure of forming small homogenous clusters throughout the …


Planar Visual Fusion Scintigraphy, Jacob Puthiamadathil May 2005

Planar Visual Fusion Scintigraphy, Jacob Puthiamadathil

Theses

Planar scintigraphy, while providing useful information about the distribution of the radiopharmaceutical being used, often does not provide adequate information about the surrounding anatomical structures. A proposed method to solve this problem is by registering and fusing a scintigraphic image with a digital visual image. Fusing planar scintigraphic images with visual photographic images to supply an anatomic correlate to regions of radiopharmaceutical accumulation has been explored in this study. The digital visual image will provide a context for the relevant structures in the scintigraphic image. The validity of using one set of affine transformation parameters for registering all patient data …


Enabling Cost Aware Routing With Auctions In Wireless Ad-Hoc Networks, Ali Yuksel May 2005

Enabling Cost Aware Routing With Auctions In Wireless Ad-Hoc Networks, Ali Yuksel

Theses

Battery power is a precious resource in wireless ad-hoc networks, and most routing protocols that have been proposed so far do not generate cost efficient routes. In this thesis, a novel auction-based cost-aware routing scheme, called CARA, is presented. CARA is designed as an extension of the MAC layer, and is shown to improve the cost efficiency of existing ad-hoc routing protocols through dynamic power control, while introducing only minimal additional overhead. The MAC layer at each node is given the capability to run local sealed-bid second-price auctions for the user data packets that need to be transmitted, and to …


Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 21, Number 8, May 2005, College Of Engineering And Computer Science, Wright State University May 2005

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 21, Number 8, May 2005, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

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


New Algorithms For Statistical Analysis Of Interval Data, Gang Xiang, Scott A. Starks, Vladik Kreinovich, Luc Longpre May 2005

New Algorithms For Statistical Analysis Of Interval Data, Gang Xiang, Scott A. Starks, Vladik Kreinovich, Luc Longpre

Departmental Technical Reports (CS)

It is known that in general, statistical analysis of interval data is an NP-hard problem: even computing the variance of interval data is, in general, NP-hard. Until now, only one case was known for which a feasible algorithm can compute the variance of interval data: the case when all the measurements are accurate enough -- so that even after the measurement, we can distinguish between different measured values Xi. In this paper, we describe several new cases in which feasible algorithms are possible -- e.g., the case when all the measurements are done by using the same (not necessarily very …


Hide It Or Unbundle It: A Comparison Of The Antitrust Investigations Against Microsoft In The U.S. And The E.U., Sue Ann Mota May 2005

Hide It Or Unbundle It: A Comparison Of The Antitrust Investigations Against Microsoft In The U.S. And The E.U., Sue Ann Mota

The University of New Hampshire Law Review

[Excerpt] "Microsoft Corporation, the world’s largest software company, has been facing antitrust scrutiny globally. In the U.S., after what’s been called the antitrust trial of the century, a consent decree was reached between Microsoft, the United States government, and several states, that closely resembled the litigated remedy that the remaining states received. Only Massachusetts appealed the litigated remedy, which was approved by the appeals court on June 30, 2004. In the United States, Microsoft was required to hide, but not remove, the Internet Explorer browser on the Windows Operating System. While antitrust litigation was ongoing in the United States against …


Improving The Performance Of Internet Data Transport, Anshul Kantawala, Jonathan S. Turner May 2005

Improving The Performance Of Internet Data Transport, Anshul Kantawala, Jonathan S. Turner

All Computer Science and Engineering Research

With the explosion of the World Wide Web, the Internet infrastructure faces new challenges in providing high performance for data traffic. First, it must be able to pro-vide a fair-share of congested link bandwidth to every flow. Second, since web traffic is inherently interactive, it must minimize the delay for data transfer. Recent studies have shown that queue management algorithms such as Tail Drop, RED and Blue are deficient in providing high throughput, low delay paths for a data flow. Two major shortcomings of the current algorithms are: they allow TCP flows to get synchronized and thus require large buffers …


Architectures For Rule Processing Intrusion Detection And Prevention Systems, Michael E. Attig May 2005

Architectures For Rule Processing Intrusion Detection And Prevention Systems, Michael E. Attig

All Computer Science and Engineering Research

High-performance intrusion detection and prevention systems are needed by network administrators in order to protect Internet systems from attack. Researchers have been working to implement components of intrusion detection and prevention systems for the highly popular Snort system in reconfigurable hardware. While considerable progress has been made in the areas of string matching and header processing, complete systems have not yet been demonstrated that effectively combine all of the functionality necessary to perform intrusion detection and prevention for real network systems. In this thesis, three architectures to perform rule processing, the heart of intrusion detection and prevention, are presented. The …


Using A Pda To Control Home Appliances, Atif Albraiki May 2005

Using A Pda To Control Home Appliances, Atif Albraiki

Renée Crown University Honors Thesis Projects - All

The Personal Digital Assistant (PDA) is a handheld device that gives users different organizational capabilities. Over the years, the functionality of PDAs has expanded tremendously to include internet connectivity and different computer applications. The purpose of my honors thesis, combined with my engineering senior design project, was to include a new functionality to the PDA and use it to control different home appliances. The goal of the project was to develop a PDA program that will communicate with a PC program, and have the PC program communicate with a microcontroller to control home appliances. My part of the project was …


Capacity And Complexity Of Hmm Duration Modeling Techniques, Michael T. Johnson May 2005

Capacity And Complexity Of Hmm Duration Modeling Techniques, Michael T. Johnson

Electrical and Computer Engineering Faculty Research and Publications

The ability of a standard hidden Markov model (HMM) or expanded state HMM (ESHMM) to accurately model duration distributions of phonemes is compared with specific duration-focused approaches such as semi-Markov models or variable transition probabilities. It is demonstrated that either a three-state ESHMM or a standard HMM with an increased number of states is capable of closely matching both Gamma distributions and duration distributions of phonemes from the TIMIT corpus, as measured by Bhattacharyya distance to the true distributions. Standard HMMs are easily implemented with off-the-shelf tools, whereas duration models require substantial algorithmic development and have higher computational costs when …


Synthesizing E-Government Stage Models – A Meta-Synthesis Based On Meta-Ethnography Approach, Keng Siau, Y. Long May 2005

Synthesizing E-Government Stage Models – A Meta-Synthesis Based On Meta-Ethnography Approach, Keng Siau, Y. Long

Research Collection School Of Computing and Information Systems

The growing interest in e-government raises the question of stages in e-government development. A few stage models for e-government have been proposed. Without a common e-government stage model, different research in e-government may be based on different stage models. This presents a difficulty in comparing and understanding different research results. In this research, we synthesize the existing e-government stage models so that there is a common frame of reference for researchers and practitioners in the area.


Synthesizing E-Government Stage Models – A Meta-Synthesis Based On Meta-Ethnography Approach, Keng Siau, Y. Long May 2005

Synthesizing E-Government Stage Models – A Meta-Synthesis Based On Meta-Ethnography Approach, Keng Siau, Y. Long

Research Collection School Of Computing and Information Systems

The growing interest in e-government raises the question of stages in e-government development. A few stage models for e-government have been proposed. Without a common e-government stage model, different research in e-government may be based on different stage models. This presents a difficulty in comparing and understanding different research results. In this research, we synthesize the existing e-government stage models so that there is a common frame of reference for researchers and practitioners in the area.


Optimal Flux Weakening In Surface Pm Machines Using Fractional-Slot Concentrated Windings, Ayman M. El-Refaie, Thomas M. Jahns May 2005

Optimal Flux Weakening In Surface Pm Machines Using Fractional-Slot Concentrated Windings, Ayman M. El-Refaie, Thomas M. Jahns

Electrical and Computer Engineering Faculty Research and Publications

A design approach is presented for achieving optimal flux-weakening operation in surface permanent-magnet (SPM) synchronous machines by properly designing the machine's stator windings using concentrated, fractional-slot stator windings. This technique makes it possible to significantly increase the machine inductance in order to achieve the critical condition for providing wide speed ranges of constant-power operation. The conditions for optimal flux weakening can be achieved while simultaneously delivering sinusoidal line-to-line back-electromotive-force waveforms and low cogging torque. A closed-form analytical model is described that can be used to design SPM machines to achieve optimal flux-weakening conditions. This technique is applied to design a …


Effects Of Load Magnitude On Diagnosing Broken Bar Faults In Induction Motors Using The Pendulous Oscillation Of The Rotor Magnetic Field Orientation, Behrooz Mirafzal, Nabeel Demerdash May 2005

Effects Of Load Magnitude On Diagnosing Broken Bar Faults In Induction Motors Using The Pendulous Oscillation Of The Rotor Magnetic Field Orientation, Behrooz Mirafzal, Nabeel Demerdash

Electrical and Computer Engineering Faculty Research and Publications

The effects of load level on the ability to diagnose broken bar faults in squirrel-cage induction motors are studied in this paper. The pendulous oscillation of the rotor magnetic field orientation is implemented as a fault signature for rotor fault diagnostic purposes at steady-state operations. Moreover, the effects of load level on the low-side band component of the stator current spectrum, and associated diagnostic difficulties in this approach particularly in the presence of motor operation from pulsewidth-modulation drives, are reported as well. These investigations were performed through testing 2-hp and 5-hp induction motors over a wide range of load levels …


Nanoindentation Technique For Characterizing Cantilever Beam Style Rf Microelectromechanical Systems (Mems) Switches, Hyukjae Lee, Ronald A. Coutu Jr., Shankar Mall, Paul E. Kladitis Apr 2005

Nanoindentation Technique For Characterizing Cantilever Beam Style Rf Microelectromechanical Systems (Mems) Switches, Hyukjae Lee, Ronald A. Coutu Jr., Shankar Mall, Paul E. Kladitis

Electrical and Computer Engineering Faculty Research and Publications

A nanoindentation technique was used to mechanically actuate a radio frequency micro-switch along with the measurement of contact resistance to investigate its applicability to characterize deflection and contact resistance behaviors of micro-sized cantilever beam switches. The resulting load–displacement relationship showed a discontinuity in slope when the micro-switch closed. The measured spring constants reasonably agreed with theoretical values obtained from the simple beam models. The change in contact resistance during test clearly indicated micro-switch closure but it did not coincide exactly with the physical contact between two electric contacts due to a resistive contaminated film.