Engineering Commons^™

Interval Mathematics For Analysis Of Multiresolutional Systems, Vladik Kreinovich, Richard Alo

Departmental Technical Reports (CS)

The more complex the problem, the more complex the system necessary for solving this problem. For very complex problems, it is no longer possible to design the corresponding system on a single resolution level, it becomes necessary to have multiresolutional systems. When analyzing such systems -- e.g., when estimating their performance and/or their intelligence -- it is reasonable to use the multiresolutional character of these systems: first, we analyze the system on the low-resolution level, and then we sharpen the results of the low-resolution analysis by considering higher-resolution representations of the analyzed system. The analysis of the low-resolution level provides …

Fuzzy Measures And Integrals As Aggregation Operators: Solving The Commensurability Problem, Francois Modave, Vladik Kreinovich

Departmental Technical Reports (CS)

The aim of this paper is to shed some light on the use of fuzzy measures and integrals as aggregation operators in multicriteria decision making. These techniques have been widely used on an ad hoc basis, but with no axiomatization. It is possible to obtain preference representation theorems in multicriteria decision making problems, relying on a formal parallelism between decision under uncertainty and multicriteria decision making. Though, it raises some commensurability problems. In this paper, we show how to obtain an axiomatization of multicriteria decision making problems, in a very natural way, and we show how to solve the commensurability …

Selecting A Fuzzy Logic Operation From The Dnf-Cnf Interval: How Practical Are The Resulting Operations?, I. B. Turksen, A. Esper, K. Patel, Scott A. Starks, Vladik Kreinovich

Departmental Technical Reports (CS)

In classical (two-valued) logic, CNF and DNF forms of each propositional formula are equivalent to each other. In fuzzy logic, CNF and DNF forms are not equivalent, they form an interval that contains the fuzzy values of all classically equivalent propositional formulas. If we want to select a single value from this interval, then it is natural to select a linear combination of the interval's endpoints. In particular, we can do that for CNF and DNF forms of "and" and "or", thus designing natural fuzzy analogues of classical "and" and "or" operations. The problem with thus selected "and" and "or" …

Why Is Selecting The Simplest Hypothesis (Consistent With Data) A Good Idea? A Simple Explanation, Vladik Kreinovich, Luc Longpre, Scott Ferson, Lev Ginzburg

Departmental Technical Reports (CS)

No abstract provided.

Information Security System Rating And Ranking, Rayford B. Vaughn Jr., Ambareen Sira, David A. Dampier

Computer Sciences and Electrical Engineering Faculty Research

The term assurance has been used for decades in trusted system development to express the notion of confidence in the strength of a specific system or system of systems. The unsolved problem that security engineers must struggle with is the adoption of measures or metrics that can reliably depict the assurance associated with a specific hardware and software architecture. This article reports on a recent attempt to focus needs in this area and suggests various categories of information assurance metrics that may be helpful to an organization that is deciding which set is useful for a specific application.

Phase Changes In Ni-Ti Under Laser Shock Loading, R. E. Hackenberg, D. C. Swift, J. C. Cooley, Katherine C. Chen, D. J. Thoma, D. L. Paisley, A. Hauer

Materials Engineering

Near-equiatomic Ni-Ti, known for its shape memory behavior, can decompose to martensitic phases and/or second phase compounds. This phase competition is investigated in Ni_xTi_100-x (494Ti₃ but no martensite in the AQ state, consistent with resistivity and dilatometry results which showed no hysteresis indicative of first order phase changes over 1.9 K4Ti₃ amounts (present in the AQ state) did change upon loading, indicating the importance of shock-induced heating. A thermodynamically complete equation of state (EOS) for NiTi in its B2 (CsCl) structure was generated by ab initio quantum mechanical calculations. This was tested by …

Main Ideas Behind Owa Lead To A Universal And Optimal Approximation Scheme, Ronald R. Yager, Vladik Kreinovich

Departmental Technical Reports (CS)

Ordered Weighted Averaging (OWA) operators have been successfully applied in many practical problems. We explain this empirical success by showing that these operators are indeed guaranteed to work (i.e., are universal), and that these operators are the best to use (in some reasonable sense).

From Computation With Guaranteed Intervals To Computation With Confidence Intervals: A New Application Of Fuzzy Techniques, Vladik Kreinovich, Hung T. Nguyen, Scott Ferson, Lev Ginzburg

Departmental Technical Reports (CS)

Traditional interval computations provide an estimate for the result y=f(x1,...,xn) of data processing when we know intervals X1,...,Xn that are guaranteed to contain the (unknown) actual values of the quantities x1,...,xn. Often, in addition to these guaranteed intervals, we have confidence intervals for these quantities, i.e., intervals Xi that contain the corresponding values xi with a certain probability. It is desirable, based on the confidence intervals for xi, to produce the resulting confidence interval for y. It turns out that the formulas for computing such resulting confidence interval are closely related with the formulas for processing fuzzy numbers by using …

Provisioning On-Line Games: A Traffic Analysis Of A Busy Counter-Strike Server, Wu-Chang Feng, Francis Chang, Wu-Chi Feng, Jonathan Walpole

Computer Science Faculty Publications and Presentations

This paper describes the results of a 500 million packet trace of a popular on-line, multi-player, game server. The results show that the traffic behavior of this heavily loaded game server is highly predictable and can be attributed to the fact that current game designs target the saturation of the narrowest, last-mile link. Specifically, in order to maximize the interactivity of the game itself and to provide relatively uniform experiences between players playing over different network speeds, on-line games typically fix their usage requirements in such a way as to saturate the network link of their lowest speed players. While …

Supporting Low-Latency Tcp-Based Media Streams, Ashvin Goel, Charles Krasic, Kang Li, Jonathan Walpole

Computer Science Faculty Publications and Presentations

The dominance of the TCP protocol on the Internet and its success in maintaining Internet stability has led to several TCP-based stored media-streaming approaches. The success of these approaches raises the question whether TCP can be used for low-latency streaming. Low latency streaming allows responsive control operations for media streaming and can make interactive applications feasible. We examined adapting the TCP send buffer size based on TCP's congestion window to reduce application perceived network latency. Our results show that this simple idea significantly improves the number of packets that can be delivered within 200 ms and 500 ms thresholds.

Auditory Stimulation And Its Effect On Spatial Temporal Ability, Cynthia G. Edwards

Master's Theses - Daytona Beach

This thesis was designed to detect the type of spatial ability most effected by auditory stimulation, as described in the Mozart effect. Previous research has shown enhancement of performance on the paper-folding and cutting subtest of the Stanford-Binet Intelligence Scale IV with failures to replicate in research using other measures. Seventy-five college students enrolled in introductory psychology classes were exposed to one of three types of auditory stimulation, followed by two measures of spatial ability. The Purdue Visualization of Developments test correlates with tests of spatial orientation and require analytical processing, while the Vandenberg and Kuse Mental Rotation Test is …

Simulations Of Nematic Liquid Crystals: Confined Geometries, Phase Transitions And Topological Defects, Nikolai V. Priezjev

Mechanical and Materials Engineering Faculty Publications

The physics of liquid crystals is an exciting field of research with important practical applications. In this dissertation we present the results of simulation studies of nematic liquid crystals using Monte Carlo and molecular dynamic techniques. In our first project we performed Monte Carlo Simulations of the Lebwohl-Lasher (LL) model of nematic liquid crystals confined to cylindrical cavities with perpendicular anchoring. In this particular geometry one has an interesting interplay between bulk and surface energies, which results in different director configurations inside the cylinder. Our work reconciled the apparent contradictions between the results of earlier simulations and approximate analytics theories. …

Overhang Effects On End-One-Flange Web Crippling Capacity Of Cold-Formed Steel Members, Michael W. Holesapple, Roger A. Laboube

American Iron and Steel Institute (AISI) Specifications, Standards, Manuals and Research Reports (1946 - present)

No abstract provided.

Testing Of Steel L-Headers On Wood Walls, Nahb Research Center

CCFSS Library (1939 - present)

No abstract provided.

Investigation Of The Electronic And Optical Properties Of The Strained Cdte/Znte (001) Superlattices, Amna Abdulla Ahmed Al-Zarouni

Theses

Semiconductors are distinguished among all materials by having a non-vanishing energy band gaps. They are often used in industry in the form of alloys or heterostructures in order to tailor energy gaps suitable for the desired applications. In general, semiconductor materials have broad applications in industry, ranging from micro-electronic devices, to light emitters and detectors, to laser and solar cells. In the last two decades, particular attention has been given to the II-VI semiconductor heterostructures because of their suitability as photoelectronic devices covering from the infra-red to the ultra-violet spectral ranges. The scope of this thesis belongs to the field …

Finite Element And Pullout Test Performance Of Welded Wire Mats, Bradley C. Conder

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This paper reports on the pullout test performance of welded-wire reinforcing mats. A 126-foot high mechanically stabilized earth wall was constructed at Kennecott Utah Copper. In the lower half of the wall, single lengths of 50-foot long welded-wire mats were used. In the top half of the wall, two lengths of 50-foot mats were overlapped 10 feet to create 90-foot mats. This 10-foot "lap zone" was investigated in this study.

The finite element program Plaxis was used to investigate several pullout test parameters: overburden pressure, gap width, boundary effects, and horizontal spacing of transverse elements from the pullout box face. …

Estimating The Noise Mitigation Effect Of Local Decoupling In Printed Circuit Boards, Jun Fan, Wei Cui, James L. Drewniak, Thomas Van Doren, James L. Knighten

Electrical and Computer Engineering Faculty Research & Creative Works

Local decoupling, i.e., placing decoupling capacitors sufficiently close to device power/ground pins in order to decrease the impedance of power bus at frequencies higher than the series resonant frequency, has been studied using a modeling approach, a hybrid lumped/distributed circuit model established and an expression to quantify the benefits of power bus noise mitigation due to local decoupling developed. In this work, a test board with a local decoupling capacitor was studied and the noise mitigation effect due to the capacitor placed adjacent to an input test port was measured. Closed-form expressions for self and mutual inductances of vias are …

Optical Limiting In Srbi₂Ta₂O₉ And Pbzrxti₁₋ₓo₃ Thin Films, Pingxiong Yang, Jianfeng Xu, Robert W. Schwartz, David L. Carroll, John Ballato

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Optical limiting effects in SrBi2Ta2O9 (SBT) and PbZrxTi1-xO3 (PZT) ferroelectric thin films have been observed with nanosecond laser pulses at 1.064 µm. Limiting thresholds were found to be 5.84 J/cm2 for SBT and between 4.53 and 5.93 J/cm2 for PZT, depending on composition, whereas saturation thresholds for the films were about 2.92 J/cm2 and between 2.27 J/cm2 to 2.97 J/cm2, respectively. Damage thresholds around 10.0 J/cm2 and between 10.37 J/cm2 to 10.54 J/cm2, respectively for SBT and PZT, were also determined. A possible mechanism for the observed limiting, nonlinear optical scattering from the ferroelectric domains, is discussed. These results elucidate …

Transportation Finance: Kentucky’S Structure And National Trends, Merl Hackbart, Suzanne Perkins, Mariam Fordham

Kentucky Transportation Center Research Report

Studies of state Road Fund tax structures, like studies of state General Funds, tend to focus on a state’s current tax structure compared to surrounding states and identifying possible tax changes that may make a tax system simpler, more equitable, more administratively efficient, more competitive or more “adequate.” In conducting such analysis, the inherent trade-offs among these accepted tax principles becomes apparent. Efforts to increase competitiveness may impact the adequacy of a tax system. Likewise, tax legislation intended to enhance tax administration efficiency may impact the equity of a state’s Road Fund tax structure. Such trade-offs associated with conflicting tax …

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 18, Number 8, May 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.

Cancellation Of Mri Motion Artifact In Image Plane, Eung-Kyeu Kim, Nohpill Park, Minsu Choi, S. Tamura

Electrical and Computer Engineering Faculty Research & Creative Works

In this study, a new algorithm for canceling a MRI artifact due to the translational motion in image plane is described. Unlike the conventional iterative phase retrieval algorithm, in which there is no guarantee for the convergence, a direct method for estimating the motion is presented. In previous approaches, the motions in the x(read out) direction and the y(phase encoding) direction were estimated simultaneously. However, the feature of x and y directional motions are different from each other. By analyzing their features, each x and y directional motion is canceled by the different algorithms in two steps. First, it is …

Extracting Cad Models For Quantifying Noise Coupling Between Vias In Pcb Layouts, Shaofeng Luan, Jun Fan, W. Liu, Fengchao Xiao, James L. Knighten, Norman W. Smith, Ray Alexander, Jim Nadolny, Yoshio Kami, James L. Drewniak

Electrical and Computer Engineering Faculty Research & Creative Works

A method to extract a lumped element prototype SPICE model is used to study noise coupling between non-parallel traces on a PCB. The parameters in this model are extracted using a PEEC-like approach, a Circuit Extraction approach based on a Mixed-Potential Integral Equation formulation (CEMPIE). Without large numbers of unknowns, the SPICE model saves computation time. Also, it is easy to incorporate into system SPICE net list to acquire the system simulation result considering the coupling between traces on the printed circuit board (PCB). A representative case is studied, and the comparison of measurements, CEMPIE simulation, and SPICE modeling are …

Airfield Pavement Deicing With Conductive Concrete Overlay, Sherif A. Yehia, Christopher Y. Tuan

Civil Engineering Faculty Proceedings & Presentations

Conductive concrete is a cementitious admixture containing a certain volumetric ratio of electrically conductive materials to attain high and stable electrical conductivity. Due to its electrical resistance, a thin overlay of conductive concrete can generate enough heat to prevent ice formation when energized by AC power. Under a research sponsored by Nebraska Department of Roads, Yehia and Tuan developed a mix specifically for concrete bridge deck deicing while meeting the ASTM and AASHTO strength specifications for overlay construction. An average thermal power of 591 W/m2 (55 W/ft2) with a heating rate of 0.56oC/min (1oF/min) was generated by a 1.2 m …

Poster: Provisioning On-Line Games: A Traffic Analysis Of A Busy Counter-Strike Server, Francis Chang, Wu-Chang Feng, Wu-Chi Feng, Jonathan Walpole

Computer Science Faculty Publications and Presentations

A poster that illustrates the client/server model employed by an multiplayer online game, focusing on bandwidth usage.

Mechanical Engineering Thermosciences Division Seminar, Robert J. Twiggs

Robert "Bob" Twiggs STEM Education Collection

A PowerPoint Presentation created by Professor Bob Twiggs titled "Mechanical Engineering Thermosciences Division Seminar" from May 1, 2002.

Bending Strength Of Hybrid Cold-Formed Steel Beams, Chi Ling Pan, Wei Wen Yu

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

For the purpose of determining the load-carrying capacity of cold-formed steel structural members, the effective width approach has been used. Since most studies were limited only to the structural members, which were assembled from the same material in a given section, this investigation was concentrated on a study of structural strength and behavior of hybrid cold-formed steel beams subjected dynamic loads. An investigation was also conducted to study the validity of effective design width formulas for the design of these specimens. The materials used in this study were 25 AK and 50 SK sheet steels. A total of 72 spot-welded …

Fdtd Modeling Of Skin Effect, Chen Wang, James L. Drewniak, Min Li, Jun Fan, James L. Knighten, Norman W. Smith, Ray Alexander, Jingyu Huang

Electrical and Computer Engineering Faculty Research & Creative Works

The data rates and clock speeds of current highspeed signals are increasing rapidly, consequently, not only the lossy nature of FR-4 but also the lossy nature of good conductors, such as copper, need to be taken into account in high-speed signal designs. In order to well predict the loss caused by both dielectric loss and skin effect loss, a suitable simulation tool is needed. A surface impedance boundary condition (SIBC) algorithm was implemented in FDTD modeling herein to accommodate the skin effect loss due to finite conductivity of good conductors. Good agreement between the FDTD result and the measurements as …

Electron–Phonon Interactions In Htsc Cuprates, Takeshi Egami, J-H Chung, Rj Mcqueeney, Mohana Yethiraj, Herbert A. Mook, C. Frost, Y. Petrov, Fatih Dogan, Yasuhiro Inamura, Masatoshi Arai, Setsuuko Tajima, Yasuo Endoh

Materials Science and Engineering Faculty Research & Creative Works

Phonons have been generally considered to be irrelevant to the high-temperature superconductivity in the cuprates. However, such a bias is usually based upon the assumption of conventional electron–phonon coupling, while in the cuprates the coupling can be rather unconventional because of strong electron correlation. We present the results of our recent measurements of phonon dispersion in YBa₂Cu₃O_6+x by inelastic neutron scattering. These suggest certain phonon modes interact strongly with electrons and are closely involved in the superconductivity phenomenon with possible contribution to pairing.

Evaluation Of Lead Anode Reactions In Acid Sulfate Electrolytes: Ii. Manganese Reactions, Pu Yu, Thomas J. O'Keefe

Materials Science and Engineering Faculty Research & Creative Works

Lead alloys containing calcium-tin, silver, or similar combinations are the primary insoluble anodes used for copper and zinc electrowinning. One potential concern with these anodes is the detrimental effect on cathode purity from incorporation of lead corrosion products. Other factors which are important to process economics are the reaction potential and overpotential required for oxygen evolution. In addition to the inherent overpotential, impurities in the electrolyte can have a significant polarization impact, such as the films that may form when manganese is present. In order to gain a better understanding of the fundamental behavior of various concentrations of manganese ions …

Room-Temperature Homogeneous Nucleation Synthesis And Thermal Stability Of Nanometer Single Crystal Ceo₂, X.-D. Zhou, Wayne Huebner, Harlan U. Anderson

Materials Science and Engineering Faculty Research & Creative Works

Nanometer (about 4~5nm) CeO₂ single crystals were first synthesized by room-temperature homogeneous nucleation; the size was determined by electron microscopy and specific surfaced area of the particles. Modeling revealed that the surface energy of as-synthesized nanometer single crystals was in the range of 2.8-3.7J/m². Crystal growth mechanisms change over the temperature regimes, from boundary diffusion over low-temperature regime (E_α=0.16eV) to bulk diffusion (E_α=0.50eV) over high-temperature region.