Computer Sciences Commons^™

A Distributed Discrete-Time Neural Network Architecture For Pattern Allocation And Control, A.T. Chronopoulos, Jagannathan Sarangapani

Computer Science Faculty Research & Creative Works

No abstract provided.

Modeling A Real-Time Economics Simulation With User-Coded Agents In An Object-Oriented Database, Kevin Simons

Honors Theses

A simulation tbat models the stock market with real-time stock quotes was created. Users can translate their own theories about investing into Java code, which is then used to create an intelligent agent. The agent is inserted into the simulation, which allows the agent to gather data from the model. Based on this data, the agent uses the algorithm the user wrote to buy and sell stocks. Such as model provides a means of testing investment theories before investing.

A Web Content Management And Personalization Model Using One-To-One Strategy For Higher Educational Institutions, Yee Pong Ng

Masters Theses

This research explored a Web content management and personalization model for higher educational institutions. Through a review of literature and data collected from users, it formulated a conceptual model for Web content management and personalization. The study used the Web site of School of Technology at Eastern Illinois University as a typical case from which to develop the model for higher educational institutions. Understanding the factors influencing user attitudes about the adoption of new Web technologies is extremely important. Such an understanding can help Web developers develop a theoretical framework for a Web model as well as identify its components. …

Decentralized Control For Coordinated Flow Of Multi-Agent Systems, Valentino Crespi, George Cybenko, Daniela Rus, Massimo Santini

Computer Science Technical Reports

This paper describes a distributed algorithm for coordinating the flow of a mass of vehicles approaching a highway exit or a tollbooth. We provide the problem formulation, a general methodology for distributed control and an instantiation of this methodology to the coordinated flow problem. We analyze our algorithm and provide experimental data.

Sar Simulations In Wireless Communication And Safety Discussions In The Society, M. O. Özyalçin, Funda Akleman, Levent Sevgi̇

Turkish Journal of Electrical Engineering and Computer Sciences

Numerical simulation in cellular phone - human tissue interaction is discussed in this paper. The powerful time domain (TD) techniques, the transmission line matrix (TLM) and the finite-difference time-domain (FDTD) methods, are used to model mutual effects. The purpose is to calculate specific absorption rate (SAR; defined as the power absorbed by the unit mass of the tissue), validate the codes and verify the results. Also, effectiveness of the SAR parameter in determination of the exposure limits for human health and environmental pollution is discussed.

Preface, Alexander Kurz

Engineering Faculty Articles and Research

No abstract provided.

Definability, Canonical Models, And Compactness For Finitary Coalgebraic Modal Logic, Alexander Kurz, Dirk Pattinson

Engineering Faculty Articles and Research

This paper studies coalgebras from the perspective of the finitary observations that can be made of their behaviours. Based on the terminal sequence, notions of finitary behaviours and finitary predicates are introduced. A category Behω(T) of coalgebras with morphisms preserving finitary behaviours is defined. We then investigate definability and compactness for finitary coalgebraic modal logic, show that the final object in Behω(T) generalises the notion of a canonical model in modal logic, and study the topology induced on a coalgebra by the finitary part of the terminal sequence.

Pricing And Product Mix Optimization In Freight Transportation, Michael F. Gorman

MIS/OM/DS Faculty Publications

We propose improved pricing and market mix can improve the profitability of the freight transportation provider through the reduction of equipment repositioning costs. We hypothesize that because of complexities surrounding pricing and equipment repositioning costing, existing pricing strategies in freight transportation fail to fully consider these costs. We test this hypothesis in an applied setting in which Monte Carlo simulation captures the stochasticity of market conditions inherent in the problem. We use a heuristic to improve the nondifferentiable, discontinuous objective function.

Our results from test cases show with high confidence that current prices are not optimal, as indicated by a …

A Developmental Approach To Anchoring, Doug Blank, Deepak Kumar, Lisa Meeden

Computer Science Faculty Research and Scholarship

No abstract provided.

A Developmental Approach To Intelligence, Doug Blank, Deepak Kumar, Lisa Meeden

Computer Science Faculty Research and Scholarship

In this paper we present a developmental approach to- ward creating intelligent systems. Although embracing an emergent paradigm, we also propose an architecture such that symbols have their proper place. To explore this methodology, we are developing our system on real robots. Robotic approaches usually invoke the so-called “symbol grounding problem” (Harnad 1990). However, our developmental approach bypasses the problem by generating the symbols. Thus, in a sense, the symbols are inherently grounded to the physical objects they des- ignate. We argue that a general theory of intelligence that takes a top-down perspective will be inherently in- complete.

Scale And Orientation-Invariant Scene Similarity Metrics For Image Queries, James Carswell

Articles

In this paper we extend our previous work on shape-based queries to support queries on configurations of image objects. Here we consider spatial reasoning, especially directional and metric object relationships. Existing models for spatial reasoning tend to rely on pre-identified cardinal directions and minimal scale variations, assumption that cannot be considered as given in our image applications, where orientations and scale may vary substantially, and are often unknown. Accordingly, we have developed the method of varying baselines to identify similarities in direction and distance relations. Our method allows us to evaluate directional similarities without a priori knowledge of cardinal directions, …

Walkthrough In Complex Environments At Interactive Rates Using Level-Of-Detail, Alper Selçuk, Uğur Güdükbay, Bülent Özgüç

Turkish Journal of Electrical Engineering and Computer Sciences

One of the biggest problems in computer graphics is displaying huge geometric models at interactive rates. A lot of work has been done to achieve the required frame-rates in architecture, simulation, computer-aided design and entertainment applications. In this paper, a system that enables walkthrough in complex environments using level-of-detail approximations is explained. The system uses hierarchical triangulated models as input. In the preprocessing phase, multiresolution models of objects are created using polygonal simplification techniques. During walkthrough, fast frustum culling based on bounding boxes is performed to eliminate branches of hierarchy that are not visible. An appropriate level for detail of …

A New Petri-Net-Based Synthesis Technique For Supervisory Control Of Discrete Event Systems, Murat Uzam, Anthony H. Jones

Turkish Journal of Electrical Engineering and Computer Sciences

A new Petri-net-based top-down synthesis technique for supervisory control of Discrete Event Systems (DES) is proposed to solve the forbidden state problem. The supervisors obtained are compiled supervisors, whose control policy is represented as a net structure, as opposed to mapping supervisors, whose control policy is computed as a feedback function of the marking of the system. The compiled supervisors obtained by using the technique proposed in this paper are both nonblocking and maximally permissive. The supervisors to be synthesised consist of a controlled Automation Petri Net model of the system. Automation Petri Nets (APN) include the following extensions to …

A Note On The Poisson Summation Formula And Its Application To Electromagnetic Problems Involving Cylindrical Coordinates, Anastassios H. Panaretos, Hristos T. Anastassiu, Dimitra I. Kaklamani

Turkish Journal of Electrical Engineering and Computer Sciences

A modified version of the Poisson Summation Formula is derived,involving the Fourier-Bessel Transform of the kernel function, as opposed to the conventional Fourier Transform engaged in the standard formula. This novel form can be applied to problems employing cylindrical coordinates, such as the fast evaluation of the dyadic Green's function in a waveguide or cavity of circular cross-section.

A Time Domain Uniform Geometrical Theory Of Slope Diffraction For A Curved Wedge, Prabhakar H. Pathak, Paul R. Rousseau

Turkish Journal of Electrical Engineering and Computer Sciences

A time domain version of the uniform geometrical theory of diffraction (TD-UTD) is developed to describe, in essentially closed form, the field which is produced via slope diffraction at a perfectly conducting, arbitrarily curved wedge excited by a time impulsive wave that exhibits a rapid spatial variation near the edge of the wedge. This TD-UTD slope diffracted field for a curved wedge is obtained by a Fourier inversion of the corresponding frequency domain UTD expression. An analytical signal representation of the transient fields is used since it is convenient, and because it circumvents some of the difficulties, which especially arise …

A Novel Mom Approach For Obtaining Accurate And Efficient Solutions In Optical Rib Waveguide, Namik Yener, Ercan Topuz

Turkish Journal of Electrical Engineering and Computer Sciences

The optical rib waveguide (ORW) plays an important role in the design of several integrated optical devices. Various methods have been proposed for obtaining the modal field solutions in ORW. However, to the best of our knowledge none of them is capable of providing accurate full-wave benchmark solutions. Here we present a novel MoM approach wherein the modes of a loaded rectangular waveguide are utilized as basis functions and demonstrate that this approach is very efficient and yields highly accurate full-wave results which can serve as benchmark solutions in assessing the quality of the data reported in the literature.

The Geometric Mean As A Generator Of Truth-Value In Heuristic Expert Systems: An Improvement Over The Fuzzy Weighted Arithmetic Mean, Walter L. Dixon

CCAC Theses and Dissertations

Many earlier expert systems that were modeled after MYCIN, the first expert system, employed truth-value factors for their rule antecedents (premises) and consequents (conclusions). These crisp truth-value factors were usually called certainty factors and attempted to provide a measure of confidence and computational capability to the analysis of rule uncertainty (Shortliffe, 1977; Kandel, 1994). However, in the literature criticism has been often expressed concerning the lack of precision a crisp truth/certainty factor value conveys (Zadeh, 1983; Turban, 1993). Zadeh (1973) and Xingui (1988) utilized the weighted fuzzy average algorithm to improve the precision of truth/certainty factor values. Kandel (1994) further …

A Technique For Visualizing Software Architectures, Jon M. Inouye

CCAC Theses and Dissertations

Software architecture appeared in the early 1990s as a distinct discipline within software engineering. Models based on software architecture attempt to reduce the complexity of software by providing relatively coarse-grained structures for representing different aspects of software development. A software architecture typically consists of various components and connections arranged in a specific topology. Elements of the topology can serve as abstractions on (for example) modules, objects, protocols or interfaces. The meaning of the topology depends on viewpoint.

Software architectures' can be described using an architecture description language (ADL). The key goals of ADLs are to communicate alternate designs to the …

An Empirical Investigation Of Employee Perceptions Of Outsourcing Success Of Information Technology Operations, Lynda Roberson Louis

CCAC Theses and Dissertations

Outsourcing is defined as the contracting out of all or parts of a company's functional work. While most outsourcing initiatives attempt to open a line of communication between upper management and affected employees, little effort is made to assess and incorporate employee perceptions into the outsourcing deal. Little research exists that addresses employee perceptions of outsourcing Information Technology (IT) functions and operations and the effects such outsourcing have on the employee. This study investigated the perceptions of employees directly involved in IT outsourcing deals in an effort to relate these perceptions to factors identified in earlier studies. The following human …

Enterprise Integration Modeling Linking Enterprise Integration Architecture With Business Strategy Planning, Easton B. Rhodd

CCAC Theses and Dissertations

The goals for this study were twofold. The first goal was to identify planning variables for linking both organizational and architectural objectives for developing enterprise integration architecture. The second goal was to validate enterprise integration modeling methodology as a viable planning tool for the design, development, and maintenance of the enterprise integration architecture.

This lack of linkage at the intellectual dimension level can be characterized as having a dysfunctional effect on enterprise integration strategy formulation and infrastructure development. There is a disjoint between adoptions of appropriate information technology in relation to organizational objectives. This includes misapplication of investments in information …

The Design Of Online Learning Communities For Older Adults, Martha Marie Snyder

CCAC Theses and Dissertations

Rapid, ongoing advancements in the growth of the Internet and web-based technology coupled with the steadily increasing number of older adults in our society create a significant need for the design of safe, convenient, and accessible online learning communities for this demographic. The primary goal of this dissertation was to conduct formative research into methodologies for developing a new instructional-design theory for establishing online learning communities for older adults. The aim of this work was to apply formative research, which is a type of developmental research used to create a new design theory or improve an existing theory, to the …

An Efficient Middleware Architecture Supporting Real-Time Distributed Object Programming, Erhan Saridoğan, Nadi̇a Erdoğan

Turkish Journal of Electrical Engineering and Computer Sciences

With the increasing demand for distributed real-time systems, the need for programming tools and execution platforms useful in development of such application systems is widely recognized. This paper presents CORD-RTS, an efficient middleware architecture that provides support for real-time distributed object programming. The communication infrastructure and various components of the middleware, which support several modes of interactions among distributed real-time objects, along with its real-time features and services, are discussed in detail.

A New Congestion Control Mechanism Proposed For The Sscop Protocol, A. Hali̇m Zai̇m

Turkish Journal of Electrical Engineering and Computer Sciences

International Telecommunication Union, Telecommunications Sector (ITU-T) Recommendation Q.2110 states that the update of a granted credit window to the transmitter (VR(MR)) is implementation dependent. In this paper, a new algorithm is designed to control the traffic flow coming from malfunctioning users. The VR(MR) parameter is controlled for that purpose. The simulation results show that this new technique nearly doubles the system performance.

Scalar Wave Diffraction By Perfectly Soft Thin Circular Cylinder Of Finite Length; Analytical Regularization Method, Eylem Özkan, Fati̇h Di̇kmen, Yury Alexanderovich Tuchkin

Turkish Journal of Electrical Engineering and Computer Sciences

A new mathematically rigorous and numerically effective method for solving the boundary value problem of scalar wave diffraction by an infinitely thin circular cylindrical screen of finite length is proposed. The method is based on the combination of the Orthogonal Polynomials Approach, and on the ideas of the methods of analytical regularization. As a result of the suggested regularization procedure, the initial boundary value problem is equivalently reduced to the infinite system of the linear algebraic equations of the second kind, i.e. to an equation of the type (I + H)x = b in the space \ell _{2} of square …

Y2k Serendipity: Benefits And Spinoffs, Roy Gwen Taunton

CCAC Theses and Dissertations

The primary purpose of the researcher this study was to determine what, if any, unexpected benefits, spin-offs, and other "serendipitous" events occurred as a result of the year 2000 remediation process undertaken by businesses, industry, and other organizations. This was measured through the use of an online survey instrument comprised of a series of questions designed to measure and discover those benefits. The survey was sent to approximately 50 different businesses/organizations during the pilot stage of this study and 250 during the main stage of this study. These businesses/organizations were randomly selected from the sampling frame using random sampling techniques. …

The Use Of A Genetic Algorithm To Evolve Networks For A Natural Language Processing Task, Alexander E. Dimov '02

Honors Projects

In this project a novel approach was taken for performing a natural language task. The task requires a neural network to predict the grammatical category of the next word in a stream of sentences. There are two main reasons why this task is interesting. In natural language processing, it is sometimes very difficult to determine the grammatical category of a word in a sentence when that word could belong to different grammatical categories depending on the context. For example, the word "run" can either be a noun or a verb in a certain sentence. The ability to correctly determine the …

Hybrid Sr Arq Scheme Using Trellis Coded Modulation For Point-To-Multipoint Communication Over Nonstationary Channels, Necmi̇ Taşpinar

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a type-I hybrid SR ARQ scheme using trellis coded modulation (TCM) for point-to-multipoint communication was analyzed on nonstationary broadcast channels where the channel bit error rate (BER) varies over time. A nonstationary channel is modelled as a two-state Markov chain. In the numerical calculations, it is found that, for a given p_{1} and \bar \varepsilon , the values of the average burst length \bar b have a very small influence on the throughput. Numerical results show that the throughput is better for values between 10 ^{-6} and 10 ^{-4}of average bit error rate \bar \varepsilon if the …

My Library At Virginia Commonwealth University: Third Year Evaluation, Jimmy Ghaphery

VCU Libraries Faculty and Staff Publications

My Library is a personalization tool that allows the library user to consolidate frequently used library resources and services. Since 1998, My Library has been available as a web page to users of the Virginia Commonwealth University Libraries. An evaluation of My Library use at Virginia Commonwealth University (VCU) was completed and published in 2000. This article reports on a follow up study that took place between March 2000 and December 2001. The article also discusses the value of My Library as a teaching tool at VCU.

Interoperable Web Services For Computational Portals, Marlon Pierce, Geoffrey C. Fox, Choonhan Youn, Steve Mock, Kurt Mueller

Electrical Engineering and Computer Science - All Scholarship

Computational web portals are designed to simplify access to diverse sets of high performance computing resources, typically through an interface to computational Grid tools. An important shortcoming of these portals is their lack of interoperable and reusable services. This paper presents an overview of research efforts undertaken by our group to build interoperating portal services around a Web Services model. We present a comprehensive view of an interoperable portal architecture, beginning with core portal services that can be used to build Application Web Services, which in turn may be aggregated and managed through portlet containers.

A Practical Approach To Solve Secure Multi-Party Computation Problems, Wenliang Du, Zhijun Zhan

Electrical Engineering and Computer Science - All Scholarship

Secure Multi-party Computation (SMC) problems deal with the following situation: Two (or many) parties want to jointly perform a computation. Each party needs to contribute its private input to this computation, but no party should disclose its private inputs to the other parties, or to any third party. With the proliferation of the Internet, SMC problems becomes more and more important. So far no practical solution has emerged, largely because SMC studies have been focusing on zero information disclosure, an ideal security model that is expensive to achieve. Aiming at developing practical solutions to SMC problems, we propose a new …