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Full-Text Articles in Engineering

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 18, Number 5, February 2002, College Of Engineering And Computer Science, Wright State University Feb 2002

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 18, Number 5, February 2002, 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.


Cxquery: A Novel Xml Query Language, Peter Revesz, Yi Chen Jan 2002

Cxquery: A Novel Xml Query Language, Peter Revesz, Yi Chen

School of Computing: Conference and Workshop Papers

XML is becoming the data exchange standard on the Internet. Previously proposed XML query languages, such as XQuery, Quilt, YALT, Lorel, and XML-QL, lack schema definition of the query result; therefore, they are limited for defining views, integrating data, updating, and further querying, all of which are often needed in e-Business applications. We propose a novel XML query language called CXQuery, which defines the schema of the query results explicitly and can easily define views, and integrate, update, and query XML data. In addition, CXQuery can express spatial and spatio-temporal queries using a constraint-based querying approach.


Closed Streamlines In Flow Visualization, Thomas Wischgoll Jan 2002

Closed Streamlines In Flow Visualization, Thomas Wischgoll

Computer Science and Engineering Faculty Publications

Vector Fields occur in many of the problems in science and engineering. In combustion processes for instance, vector fields describe the flow of the gas. This process can be enhanced using vector field visualization techniques. Also wind tunnel experiments can be analyzed. An example is the design of an air wing. The wing can be optimized to crate a smoother flow around it. Vector field visualization methods help the engineer to detect critical features of the flow. Consequently, feature detection methods gained great importance during the last years.

Topological methods are often used to visualize vector fields because they clearly …


Implementation Of A Si/Sic Hybrid Optically Controlled High-Power Switching Device, Prashant Bhadri, Kuntao Ye, Elena A. Guliants, Fred R. Beyette Jr. Jan 2002

Implementation Of A Si/Sic Hybrid Optically Controlled High-Power Switching Device, Prashant Bhadri, Kuntao Ye, Elena A. Guliants, Fred R. Beyette Jr.

Electrical and Computer Engineering Faculty Publications

The ever-increasing performance and economy of operation requirements placed on commercial and military transport aircraft are resulting in very complex systems. As a result, the use of fiber optic component technology has lead to high data throughput, immunity to EMI, reduced certification and maintenance costs and reduced weight features. In particular, in avionic systems, data integrity and high data rates are necessary for stable flight control. Fly-by-Light systems that use optical signals to actuate the flight control surfaces of an aircraft have been suggested as a solution to the EMI problem in avionic systems. Current fly-by-light systems are limited by …


Santa Clara Magazine, Volume 44 Number 3, Winter 2002, Santa Clara University Jan 2002

Santa Clara Magazine, Volume 44 Number 3, Winter 2002, Santa Clara University

Santa Clara Magazine

10 - GLOBALIZATION EMPOWERS GOOD AND EVIL By Rob Elder. Thomas Friedman, Pulitzer Prizewinning author and international affairs columnist for The New York Times, discusses this complex issue during a visit to campus.

14 - ON THE COLLISION OF WORLDS By Fred White. Corny science fiction movies inspire an SCU English professor to ponder deeply cosmic questions.

18 - THE CAMPAIGN FOR SANTA CLARA By Elizabeth Kelley Gillogly '93. SCU launches the largest campaign in its history, with plans for endowed scholarships, a new library, a new building for the Leavey School of Business, and much more.


Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 18, Number 4, January 2002, College Of Engineering And Computer Science, Wright State University Jan 2002

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 18, Number 4, January 2002, 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.


Translation Of 'Balika Badhu: A Selected Anthology Of Bengali Short Stories', Monish Ranjan Chatterjee Jan 2002

Translation Of 'Balika Badhu: A Selected Anthology Of Bengali Short Stories', Monish Ranjan Chatterjee

Electrical and Computer Engineering Faculty Publications

This project, which began with the desire to render into English a rather long tale by Bimal Kar about five years ago, eventually grew into a considerably more extended compilation of Bengali short stories by 10 of the most well-known practitioners of that art since the heyday of Rabindranath Tagore. The collection is limited in many ways, not the least of which being that no woman writer has been included, and that it contains only a baker's dozen stories (if we count Bonophool's micro-stories collectively as one ) — a number pitifully small considering the vast and prolific field of …


University Of Texas At Tyler Catalog, 2002-2004, University Of Texas At Tyler Jan 2002

University Of Texas At Tyler Catalog, 2002-2004, University Of Texas At Tyler

Catalogs

Archives Space instance: https://archivesspace.uttyler.edu/repositories/2/archival_objects/22361


An On-Line Acid-Base Titration Applet In The Generic Tutorial System For The Sciences Project, Thomas Lee Gummo Jan 2002

An On-Line Acid-Base Titration Applet In The Generic Tutorial System For The Sciences Project, Thomas Lee Gummo

Theses Digitization Project

The purpose of this Master's Project was to develop an Acid-Base Titration Simulator. It was also to be a part of the California State University - San Bernardino's GTSS, Generic Tutorial System for the Sciences, project. The main benefit is that students will be able to conduct titration experiments over the Internet without being in the laboratory and without costly equipment or dangerous chemicals. Instructors at the high school and college level can demonstrate the key principles of titration.


Effect Of Ga Content On Defect States In Cuin1-XGaXSe2 Photovoltaic Devices, Jennifer T. Heath, J. David Cohen, William N. Shafarman, Dongxiang Liao, Angus Rockett Jan 2002

Effect Of Ga Content On Defect States In Cuin1-XGaXSe2 Photovoltaic Devices, Jennifer T. Heath, J. David Cohen, William N. Shafarman, Dongxiang Liao, Angus Rockett

Faculty Publications

Defects in the band gap of CuIn1-xGaxSe2 have been characterized using transient photocapacitance spectroscopy. The measured spectra clearly show response from a band of defects centered around 0.8 eV from the valence band edge as well as an exponential distribution of band tail states. Despite Ga contents ranging from Ga/(In+Ga)=0.0 to 0.8, the defect bandwidth and its position relative to the valence band remain constant. This defect band may act as an important recombination center, contributing to the decrease in device efficiency with increasing Ga content.


Radiation Resistance Testing Of Mosfet And Cmos As A Means Of Risk Management, Akira Tokuhiro, Massimo F. Bertino Jan 2002

Radiation Resistance Testing Of Mosfet And Cmos As A Means Of Risk Management, Akira Tokuhiro, Massimo F. Bertino

Nuclear Engineering and Radiation Science Faculty Research & Creative Works

Whether for military, research (space, accelerator physics) and/or civilian use, risk avoidance against radiation-induced damage is not possible with COTS parts. Thus the sensible approach is risk management. We recommend a sensible risk management approach as follows: 1) know the radiation environment of the intended application to the extent possible; 2) know the effects of ionizing radiation on the component(s) of interest; 3) know the requirements of the application; 4) identify the candidate or chosen components; 5) test the components; 6) design-in safety factor margins to the extent possible.


Atmospheric Turbulence Conditions Leading To Focused And Folded Sonic Boom Wave Fronts, Andrew A. Piacsek Jan 2002

Atmospheric Turbulence Conditions Leading To Focused And Folded Sonic Boom Wave Fronts, Andrew A. Piacsek

All Faculty Scholarship for the College of the Sciences

The propagation and subsequent distortion of sonic booms with rippled wave fronts are investigated theoretically using a nonlinear time-domain finite-difference scheme. This work seeks to validate the rippled wave front approach as a method for explaining the significant effects of turbulence on sonic booms [A. S. Pierce and D. J. Maglieri, J. Acoust. Soc. Am. 51, 702–721 (1971)]. A very simple description of turbulence is employed in which velocity perturbations within a shallow layer of the atmosphere form strings of vortices characterized by their size and speed. Passage of a steady-state plane shock front through such a vortex layer …


Fiber Optic Sensor Response To High Levels Of Fat In Cream, Czarena L. Crofcheck, Frederick A. Payne, Clair L. Hicks, M. Pinar Mengüç, Sue E. Nokes Jan 2002

Fiber Optic Sensor Response To High Levels Of Fat In Cream, Czarena L. Crofcheck, Frederick A. Payne, Clair L. Hicks, M. Pinar Mengüç, Sue E. Nokes

Biosystems and Agricultural Engineering Faculty Publications

A light backscatter technique using optical fibers to deliver and receive light was investigated for measuring the milkfat content of unhomogenized cream. Light backscatter through cream at wavelengths of 450 to 900 nm was measured for fiber separation distances from 2 to 6.5 mm and for cream containing 10 to ~40 weight percent (wt%) milkfat. Unhomogenized cream (~40 wt% milkfat) was mixed with skim milk (~0.05 wt% milkfat) to yield samples with five different milkfat levels. Three optical response models were tested for correlation with milkfat content: one using the light intensity measurement at a single separation distance, the second …


An Analysis Of A Private-Key Cryptosystem, Wei-Wey Tan Jan 2002

An Analysis Of A Private-Key Cryptosystem, Wei-Wey Tan

Student Works (2000-2009)

In this dissertation, we have presented a new block cipher. The proposed block cipher is a Substitution-Permutation network cryptosystem with a block length of 128 bits and key length of 256 bits. With the increased key length and block size, the proposed block cipher has greater security over DES. A modular design approach was applied. The cipher has three major building blocks and their interaction has been carefully chosen to achieve better security and performance. Algorithmic S­-Boxes are used to provide confusion and nonlinearity in the cipher. The proposed cipher uses a highly diffusive diffusion layer, which is a combination …


A Genetic Algorithm Solution To The Shortest Path Problem In Ospf And Mpls, Wee Jing Tee Wee Jing Jan 2002

A Genetic Algorithm Solution To The Shortest Path Problem In Ospf And Mpls, Wee Jing Tee Wee Jing

Student Works (2000-2009)

This project studies and explores the potential of using genetic algorithm to solve the shortest path problem in Open Shortest Path First (OSPF) and Multiprotocol Label Switching (MPLS). The most critical task for developing a genetic algorithm to the shortest path problem is to how to encode a path in a network. In this project, two genetic algorithm solutions arc developed for the above two problem domains, i.e. Previous-node-based Encoding to solve the shortest path problem in OSPF and Priority-based Encoding to solve the shortest path problem in MPLS. For each of the shortest path problem domains, the proposed solution …


Level Set Segmentation Of Mr Images For Extraction Of Femur Bone And Tissues, Christina Shanti Nayagam Jan 2002

Level Set Segmentation Of Mr Images For Extraction Of Femur Bone And Tissues, Christina Shanti Nayagam

Student Works (2000-2009)

This research explores a potentially useful segmentation algorithm, known as the level set method. It is suitable for images obtained from the Magnetic Resonance Imaging (MRJ) modality, despite the fact that MR images have low contrast between bone and tissue. The level set method is a numerical technique designed to track the evolution of an interface. The fast marching version of the method is implemented for two-dimensional (2-D) and three-dimensional (3-D) segmentation in this research. Femur segmentation is the main thrust of this thesis, however brain and heart images are also presented. Pre-processing steps are first performed for the 2-0 …


Issues In Implementing Ipv6 In The X-Kernel Simulator, Raja Singam Thillainathan Jan 2002

Issues In Implementing Ipv6 In The X-Kernel Simulator, Raja Singam Thillainathan

Student Works (2000-2009)

The new Internet Protocol Version 6(IPv6) or Internet Protocol Next Generation (TPNG) is bound to replace the existing Internet Protocol Version 4(TPv4). This new protocol is to address and resolve the limitations of the existing Internet Protocols. At the moment the new protocol is still in its infancy stage, and it is being implemented by both the research society and the private sector. The x-kernel being a research project done by University of Arizona is freely available on the Internet. This x-kemel is a networking software almost similar to the Berkeley version (BSD) and it is bundled together with a …


Internet Information Server Scanner : Scanning On Url Vulnerabilities, Yu Jin Tan Jan 2002

Internet Information Server Scanner : Scanning On Url Vulnerabilities, Yu Jin Tan

Student Works (2000-2009)

This dissertation analyzes weaknesses on web servers, focusing on Microsoft's Internet Information Server (HS). As part of the research, an HS scanner (HS-SCAN) has been implemented to probe only on URL vulnerabilities. The need for a vulnerability scanner stems from the alarming number of successful attacks on computer systems that are connected to the Internet. The security flaws threatening e-businesses and the Internet community has prompted bona fide defense measures. Internet firewalls - gateways controlling access between one network and all the others - became a must-have for any organization connecting to the Net. If the firewall is considered the …


The Effect Of Weak Acids Hydrolysis On The Sol-Gel Fabrication Of Silica Thin Film, Abdul Hamid Jan 2002

The Effect Of Weak Acids Hydrolysis On The Sol-Gel Fabrication Of Silica Thin Film, Abdul Hamid

Student Works (2000-2009)

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A Vhdl Implementation Of Bist Technique In Uart Design, Mohd. Yamani Idna Idris Jan 2002

A Vhdl Implementation Of Bist Technique In Uart Design, Mohd. Yamani Idna Idris

Student Works (2000-2009)

No abstract provided.


Modelling Of Space Charge Effects In The Electrical Discharge Of Nitrogen Gas Laser, Chin Yang Chia Jan 2002

Modelling Of Space Charge Effects In The Electrical Discharge Of Nitrogen Gas Laser, Chin Yang Chia

Student Works (2000-2009)

A computer model for the simulation of a nitrogen gas discharge has been built and studied. This model was based on the fluid description of the discharge plasma. The Phoenical SHASTA Flux-Corrected Transport (FCT) algorithm is used for the solution of the fluid equations and its accuracy has been tested. The distribution of the local electrical field was calculated by the Poisson equation. The internal discharge current was calculated by Sato's equation. The motion of the charge particles was taken into account. The electrical discharge behavior was simulated by the circuit equation and solved using the fourth order Runge-Kutta method …


Thermogravimetric Studies Of Pmma On Silica, Bing Zhang, Frank D. Blum Jan 2002

Thermogravimetric Studies Of Pmma On Silica, Bing Zhang, Frank D. Blum

Chemistry Faculty Research & Creative Works

The thermal degradation of poly(methyl methacrylate) (PMMA) has been studied extensively. It is well accepted that the degradation process is a radical chain reaction involving initiation, depropagation, transfer, and termination reactions. In the degradation process, the factors having observable effects on the decomposition behavior include molecular mass, polydispersity, tacticity, and sample dimensions. The effects of tacticity on the degradation behavior of PMMA were investigated by Kashiwagi et al., Jellinek et al. And Chiamtore et al. The results indicated that both isotactic and syndiotactic PMMA have similar decomposition pathways and activation energies. Isotactic PMMA will decompose at a slightly lower temperature …


Effect Of Polymer-Surface Mobility On Adhesion In Poly(Methyl Methacrylate)-Tape System, Bhavesh C. Gandhi, Frank D. Blum, Lokeswarappa R. Dharani Jan 2002

Effect Of Polymer-Surface Mobility On Adhesion In Poly(Methyl Methacrylate)-Tape System, Bhavesh C. Gandhi, Frank D. Blum, Lokeswarappa R. Dharani

Chemistry Faculty Research & Creative Works

The interaction between two polymer layers, especially adhesion between them, plays an important role in polymer processing and other applications. Detailed knowledge of the molecular structure and dynamics of polymer interfaces, and how they relate to macroscopic mechanical properties, should help designers construct more functional systems. Unfortunately, there have been few studies where both molecular and macroscopic studies have been performed on similar systems. In previous studies from our group, we have probed the dynamics of poly(methyl acrylate) (PMA) and thermal behavior of poly(methyl methacrylate) (PMMA) on silica. These studies helped us paint a picture for strongly bound molecules on …


A 0.5 Μm Thick Polysilicon Schottky Diode With Rectification Ratio Of 10^6, Elena A. Guliants, Chunhai Ji, Young J. Song, Wayne A. Anderson Jan 2002

A 0.5 Μm Thick Polysilicon Schottky Diode With Rectification Ratio Of 10^6, Elena A. Guliants, Chunhai Ji, Young J. Song, Wayne A. Anderson

Electrical and Computer Engineering Faculty Publications

Polycrystalline Si films, 0.5-mm thick, were obtained as a result of metal-induced growth by sputtering from a Si target on 25 nm thick Ni prelayers at 525 °C. Silicon grew heteroepitaxially on the NiSi2 layer formed due to the reaction between the sputtered Si atoms and Ni. Schottky diodes were fabricated on the Si films by deposition of a Schottky metal on the front surface of the film while Ni disilicide provided an intimate ohmic contact at the back. A Pd/n-Si diode using an n-Si film annealed for 2 h at 700 °C in forming gas demonstrated a rectification ratio …


Electrical Network-Based Time-Dependent Model Of Electrical Breakdown In Water, R. P. Joshi, J. Qian, K. H. Schoenbach Jan 2002

Electrical Network-Based Time-Dependent Model Of Electrical Breakdown In Water, R. P. Joshi, J. Qian, K. H. Schoenbach

Bioelectrics Publications

A time-dependent, two-dimensional, percolative approach to model dielectric breakdown based on a network of parallel resistor–capacitor elements having random values, has been developed. The breakdown criteria rely on a threshold electric field and on energy dissipation exceeding the heat of vaporization. By carrying out this time-dependent analysis, the development and propagation of streamers and prebreakdown dynamical evolution have been obtained directly. These model simulations also provide the streamer shape, characteristics such as streamer velocity, the prebreakdown delay time, time-dependent current, and relationship between breakdown times, and applied electric fields for a given geometry. The results agree well with experimental data …


Kentucky Water Resources Research Institute Annual Technical Report Fy 2001, Kentucky Water Resources Research Institute, University Of Kentucky Jan 2002

Kentucky Water Resources Research Institute Annual Technical Report Fy 2001, Kentucky Water Resources Research Institute, University Of Kentucky

KWRRI Annual Technical Reports (USGS’s 104b Grant Program)

The FY 2001 Annual Technical Report for Kentucky consolidates reporting requirements of the Section 104(b) base grant award in a single technical report that includes: 1) a synopsis of each research project supported during the period, 2) a list of related reports, 3) a description of information transfer activities, 4) a summary of student support during the reporting period, and 5) notable achievements and awards during the year.


A Review Of Systems: New Paradigms For The Human Sciences, Martin Zwick Jan 2002

A Review Of Systems: New Paradigms For The Human Sciences, Martin Zwick

Complex Systems Faculty Publications and Presentations

This essay is a selective review of Systems: New Paradigms for the Human Sciences, edited by Gabriel Altmann and Walter A. Koch (Berlin: Walter de Gryter, 1998). It is selective because it is impossible to engage such a varied collection of systems-theoretic essays in a review of reasonable length. To invoke a relevant dialectical idea: the characteristic strength of any system is often also its characteristic weakness. One strength and weakness of the systems field is its great diversity, and this diversity is reflected in this volume by the range of subjects addressed in its 27 articles. I will not …


Sar Simulations In Wireless Communication And Safety Discussions In The Society, M. O. Özyalçin, Funda Akleman, Levent Sevgi̇ Jan 2002

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 Jan 2002

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 Jan 2002

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.