Engineering Commons^™

Development Of A Finite-Element Stored Grain Ecosystem Model, Michael D. Montross, Dirk E. Maier, Kamyar Haghighi

Biosystems and Agricultural Engineering Faculty Publications

An axisymmetric finite–element model was developed that predicts the heat, mass, and momentum transfer that occurred in upright corrugated steel storage structures due to conduction, diffusion, and natural convection using realistic boundary conditions. Weather data that included hourly total solar radiation, wind speed, ambient temperature, and relative humidity were used to model the temperature, moisture content, dry matter loss, and maize weevil development during storage with no aeration, and with ambient and chilled aeration. Periods of aeration were simulated assuming a uniform airflow rate through the grain mass. Heat and mass balances were used to calculate the temperature and absolute …

Comment On "Quadriceps Protects The Anterior Cruciate Ligament", Antonie J. Van Den Bogert

Mechanical Engineering Faculty Publications

No abstract provided.

The Evolution Of The Long Term Performance Of Fiber Reinforced Composites Materials Based On Vinyl Easter Resin, Nasser Abdullah Ali-Al Ghailani

Theses

Fiber reinforced polymer (plastic) FRP composites are different from traditional

structural materials such as steel or aluminum since the an-isotropic nature of a Fiber _ reinforced composite material creates a unique opportunity of tailoring its properties according to the design requirements. With the accelerated change in the technological sphere, FRP composite materials

have taken a paramount importance in various structural applications, where they successfully replaced conventional materials such as steel. Such success is based on the advantages offered by composite materials such as a high strength to weight ratio. However one aspect that is still delaying full acceptance of these …

On The Use Of Singular Perturbations To Neglect The Dynamic Saliency Of Synchronous Machines, Steven D. Pekarek, Michael T. Lemanski, Eric A. Walters

Electrical and Computer Engineering Faculty Research & Creative Works

A common approximation used in the analysis of power systems is the neglect of the dynamic saliency in synchronous machines. In this paper, it is shown that eliminating the error associated with neglecting dynamic saliency can be accomplished with the addition of a singular perturbation(s) into the machine model. By considering the elimination of error in such a way, singular-perturbation-based model-order-reduction techniques are used to derive detailed- and reduced-order models of synchronous machines where dynamic saliency is eliminated with zero error and no added numerical cost.

Composite Structures Using Asphalt Based Roofing Scrap Materials: Eiera -- Final Report, V. J. Flanigan, K. Chandrashekhara, Susan L. Murray

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The uses of recycled materials in composites provide the potential for large cost savings and a solution to the ever-growing disposal problem. Shingles contain petroleum based binders and fillers, which used as a valuable resource in composite production. Composites offer inherent advantages over traditional materials in regard to corrosion resistance, design flexibility and extended service life. Use of scrap-roofing shingles as a core material in glass fiber reinforced composite materials offer potential low cost composite products such as sound barrier system, railroad ties and other building materials including blocks. In the present work, processes have been developed for shredding scrap …

Automatic Target Recognition Classification System Evaluation Methodology, Christopher Brian Bassham

Theses and Dissertations

This dissertation research makes contributions towards the evaluation of developing Automatic Target Recognition (ATR) technologies through the application of decision analysis (DA) techniques. ATR technology development decisions should rely not only on the measures of performance (MOPs) associated with a given ATR classification system (CS), but also on the expected measures of effectiveness (MOEs). The purpose of this research is to improve the decision-makers in the ATR Technology development. A decision analysis framework that allows decision-makers in the ATR community to synthesize the performance measures, costs, and characteristics of each ATR system with the preferences and values of both the …

Adaptive Harmonic Balance Method For Unsteady, Nonlinear, One-Dimensional Periodic Flows, Raymond C. Maple

Theses and Dissertations

A new adaptive split-domain harmonic balance computational fluid dynamics (CFD) method is developed to solve highly nonlinear time-periodic flows such as those found in turbomachinery. The basic harmonic balance CFD method transforms an unsteady time-periodic problem into a steady-state problem by assuming a solution in the form of a Fourier series in time. The new method employs a unique multi-domain split-operator solution technique to remove a large-series stability restriction present in previous harmonic balance CFD approaches. In addition, the new method adapts the frequency content to the flow, starting with a small number of Fourier frequencies and augmenting the frequency …

Mean Performance Optimization Of An Orbiting Distributed Aperture By Warped Aperture Image Plane Comparisons, Timothy W. Parker

Theses and Dissertations

This work models the aggregate performance of satellite receiver formations functioning as orbiting interferometers as compared to filled apertures of similar geometries. These models facilitate selecting initial conditions for formations such that their control-free dynamics yield interferometry performance with minimal errors as compared to the filled apertures. The solution method draws on the dynamic models of an orbiting planar satellite formation to define the size and shape of a reference aperture and to define the degrees of freedom for the formation members. The paths of formation elements yield geometries for which the aggregate performance of the array of discrete receivers …

An Evaluation Of Facility Maintenance And Repair Strategies Of Select Companies, Christopher L. Sharp

Theses and Dissertations

Although initial construction costs are high, the cost of operation and maintenance over a facilities life-cycle is significantly higher. A common challenge for facility maintenance professionals is balancing the cost of facility Maintenance and Repair (M&R) with the benefits derived from those facilities. This thesis documents how a selection of companies implemented that balance by determining their facilities requirements based on their chosen facility condition level and how they then allocated funds. The research effort consisted of interviews with facility maintenance professionals at each company selected. The data was then used to perform a multiple case study analysis and comparison …

An Automated Coronary Artery Occlusion Device For Stimulating Collateral Development In Vivo, Richard Rys, John F. Ladisa, John P. Tessmer, Weidong Gu, Judy R. Kersten, David C. Warltier, Paul S. Pagel

Biomedical Engineering Faculty Research and Publications

Introduction: Repetitive, brief coronary artery occlusions produce collateral development in experimental animals. This model causes coronary collateralization in a highly reproducible fashion, but the process is very labor intensive. We report the design and use of a fully automated hydraulic coronary occlusion device capable of producing repetitive coronary occlusions and enhancement of coronary collateral development in dogs.

Methods: The device consists of analog electronics that allow adjustment of occlusion number, frequency, pressure and duration, and mechanical components responsible for the coronary occlusion. The motor and piston of the device are coupled to a chronically implanted hydraulic vascular occluder …

A New Approach To Robot’S Imitation Of Behaviors By Decomposition Of Multiple-Valued Relations, Uland Wong, Marek Perkowski

Electrical and Computer Engineering Faculty Publications and Presentations

Relation decomposition has been used for FPGA mapping, layout optimization, and data mining. Decision trees are very popular in data mining and robotics. We present relation decomposition as a new general-purpose machine learning method which generalizes the methods of inducing decision trees, decision diagrams and other structures. Relation decomposition can be used in robotics also in place of classical learning methods such as Reinforcement Learning or Artificial Neural Networks. This paper presents an approach to imitation learning based on decomposition. A Head/Hand robot learns simple behaviors using features extracted from computer vision, speech recognition and sensors.

Accurate Quantification Of Steady And Pulsatile Flow With Segmented K-Space Magnetic Resonance Velocimetry, Haosen Zhang, Sandra S. Halliburton, James R. Moore, Orlando P. Simonetti, Paulo R. Schvartzman, Richard D. White, George P. Chatzimavroudis

Chemical & Biomedical Engineering Faculty Publications

Conventional non-segmented magnetic resonance phase velocity mapping (MRPVM) is an accurate but relatively slow velocimetric technique. Therefore, the aim of this study was to evaluate the accuracy of the much faster segmented k-space MRPVM in quantifying flow. The axial velocity was measured in four straight tubes (inner diameter: 5.6–26.2 mm), using a segmented MRPVM sequence with seven lines of k-space per segment. The flow rate and flow volume were accurately quantified (errorssteady (r²=0.99) and pulsatile flow (r²=0.98), respectively. The measured velocity profiles and flow rates from the segmented sequence agreed …

Safety Evaluation Of New Roads, Kenneth R. Agent, Jerry G. Pigman

Kentucky Transportation Center Research Report

The primary objective of this research study was to evaluate the crash history of bypass routes to determine if there were unusual patterns or changes in the crash history on these routes over the first years of operation. The focus of the evaluation was to collect data at bypass routes opened in recent years in Kentucky. Crash patterns were summarized with recommendations made for countermeasures to reduce the probability of crashes, specifically at intersections, with an emphasis on the early stages of operation. The literature was reviewed, crash data were obtained at nine case study bypasses, and discussions were held …

Experimental Maintenance Painting On Various Bridge Painting Projects (Kentucky Highway Investigative Task No: 31), Sudhir Palle, Theodore Hopwood Ii

Kentucky Transportation Center Research Report

The Kentucky Transportation Center (KTC) at the University of Kentucky conducted a research study with the Kentucky Transportation Cabinet (KYTC) to monitor various experimental bridge painting projects. The research study Kentucky Highways Investigative Task (KHIT) No: 31 “Experimental Maintenance Painting on Various Bridge Projects During 1997-1998” covered experimental bridge projects completed through the FY 1997 and FY 1998 painting seasons (April 1 through November 15) were monitored and reported. The objectives of the research study were to:

• assess the condition of the existing paint on bridge prior to maintenance painting,
• monitor the project throughout completion,
• note problems and their resolution, …

Closed-Form Solution For A Mode-Iii Interfacial Edge Crack Between Two Bonded Dissimilar Elastic Strips, Xiangfa Wu, Yuris A. Dzenis

Department of Engineering Mechanics: Faculty Publications

A closed-form solution is obtained for the problem of a mode-III interfacial edge crack between two bonded semi-infinite dissimilar elastic strips. A general out-of-plane displacement potential for the crack interacting with a screw dislocation or a line force is constructed using conformal mapping technique and existing dislocation solutions. Based on this displacement potential, the stress intensity factor (SIF, K_III) and the energy release rate (ERR, G_III) for the interfacial edge crack are obtained explicitly. It is shown that, in the limiting special cases, the obtained results coincide with the results available in the literature. The present …

Closed-Form Solution For The Size Of Plastic Zone In An Edge-Cracked Strip, Xiang-Fa Wu, Yuris A. Dzenis

Department of Engineering Mechanics: Faculty Publications

This paper is concerned with the problem of plastic zone at the tip of an edge crack in an isotropic elastoplastic strip under anti-plane deformations. By means of complex potential and Dugdale model, the stress intensity factor and the size of plastic zone are obtained in closed-form. Furthermore, the analytic solutions for an edge crack at the free boundary of a half-space and a semi-infinite crack heading towards a free surface are determined as the limiting cases of the strip geometries.

Validation Of A Finite-Element Stored Grain Ecosystem Model, Michael D. Montross, Dirk E. Maier, Kamyar Haghighi

Biosystems and Agricultural Engineering Faculty Publications

An axisymmetric finite–element model was validated with respect to predicting the heat, mass, and momentum transfer that occurred in upright corrugated–steel storage bins due to conduction, diffusion, and natural convection using realistic boundary conditions. Hourly weather data that included hourly total solar radiation, wind speed, ambient temperature, and relative humidity were used to model the corn temperature and moisture content during storage with no aeration, and with ambient and chilled aeration. Periods of aeration were simulated assuming a uniform airflow rate through the grain mass. Sixteen bins with a capacity of 11.7 t each and instrumented with temperature cables were …

Documentation Of Context-Sensitive Design Case Studies, Jerry G. Pigman, Donald L. Hartman, Nikiforos Stamatiadis, Lisa Aultman-Hall, Sally G. Oldham

Kentucky Transportation Center Research Report

A major challenge for many current transportation projects is to plan, design and build to create a solution which will not only address the planning and engineering requirements, but also satisfy the human and natural environmental issues related to a specific project. Occasional projects of this type have been designed and built for many years, typically when there have been few alternatives otherwise. A key component to these types of projects has been a greater level of community interest and public involvement. Initial efforts to introduce the concept of increased sensitivity to community interests and the natural environment was labeled …

Comparison Of Open- And Closed-Loop Process Identification Techniques In The Time-Domain, Tony Kealy, Aidan O'Dwyer

Conference papers

Abstract: This paper describes seven methods to identify a mathematical model for a real process with a time delay. The process is the Process Trainer, PT326 from Feedback Instruments Limited. Six of the methods use the step response data and one of the methods uses the impulse response data for identification.

Dopant Effect On Local Dielectric Properties In Barium Titanate Based Electroceramics Determined By Transmission Eels, Kalpana S. Katti, Maoxu Quian, Fatih Dogan, Mehmet Sarikaya

Materials Science and Engineering Faculty Research & Creative Works

Investigates the local electronic excitations of barium titanate electro ceramic using low-loss electron energy loss spectroscopy. Process for monitoring of electronic structure of titanate; Changes in valence and conduction band states by valence state of barium; Shift of oscillator strengths of excitations in local regions.

Four-Terminal Quantum Resistor Network For Electron-Wave Computing, Diwakar Ramamurthy, Cheng-Hsiao Wu

Electrical and Computer Engineering Faculty Research & Creative Works

Interconnected ultrathin conducting wires or, equivalently, interconnected quasi-one-dimensional electron waveguides, which form a quantum resistor network, are presented here in four-terminal configurations. The transmission behaviors through such four-terminal networks are evaluated and classified. In addition, we show that such networks can be used as the basic building blocks for a possible massive wave computing machine in the future. In a network, each interconnection, a node point, is an elastic scatterer that routes the electron wave. Routing and rerouting of electron waves in a network is described in the framework of quantum transport from Landauer-Buttiker theory in the presence of multiple …

Microbial Cellulose Utilization: Fundamentals And Biotechnology, Lee R. Lynd, Paul J. Weimer, Willem H. Van Zyl, Isak S. Pretorius

Dartmouth Scholarship

Fundamental features of microbial cellulose utilization are examined at successively higher levels of aggregation encompassing the structure and composition of cellulosic biomass, taxonomic diversity, cellulase enzyme systems, molecular biology of cellulase enzymes, physiology of cellulolytic microorganisms, ecological aspects of cellulase-degrading communities, and rate-limiting factors in nature. The methodological basis for studying microbial cellulose utilization is considered relative to quantification of cells and enzymes in the presence of solid substrates as well as apparatus and analysis for cellulose-grown continuous cultures. Quantitative description of cellulose hydrolysis is addressed with respect to adsorption of cellulase enzymes, rates of enzymatic hydrolysis, bioenergetics of microbial …

Bs News

Building Services Engineering

No abstract provided.

Models Of Soil Moisture Dynamics In Ecohydrology: A Comparative Study, Andrew J. Guswa, M. A. Celia, I. Rodriguez-Iturbe

Engineering: Faculty Publications

An accurate description of plant ecology requires an understanding of the interplay between precipitation, infiltration, and evapotranspiration. A simple model for soil moisture dynamics, which does not resolve spatial variations in saturation, facilitates analytical expressions of soil and plant behavior as functions of climate, soil, and vegetation characteristics. Proper application of such a model requires knowledge of the conditions under which the underlying simplifications are appropriate. To address this issue, we compare predictions of evapotranspiration and root zone saturation over a growing season from a simple bucket-filling model to those from a more complex, vertically resolved model. Dimensionless groups of …

In Situ Corrosion Studies On The Battleship Uss Arizona, John D. Makinson, James D. Carr, Matthew A. Russell, David L. Conlin, Larry E. Murphy

Department of Mechanical and Materials Engineering: Faculty Publications

U.S. National Park Service Submerged Resources Center archaeologists and University of Nebraska-Lincoln metallurgists are assessing hull corrosion by drilling through accumulated concretions and measuring pH and corrosion potentials. Concretion samples are being analyzed to determine the role of microbes in the corrosion process, identify chemical species, and measure electrical and physical properties. The lowest values of pH and E corr occur at the metal/concretion interface. Analysis suggests a variable corrosion rate supported by hydrogen discharge and/or oxygen reduction inside the concretion.

Residual Effects Of Compost And Fertilizer Applications On Nutrients In Runoff, John E. Gilley, Bahman Eghball

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The application of compost or fertilizer at rates that exceed crop nutrient requirements can result in phosphorus (P) and nitrogen (N) accumulation in soil. This study was conducted to determine the influence of soil P and N contents on the concentrations and total amounts of P and N transported in runoff. Composted beef cattle feedlot manure or inorganic fertilizer were added from 1992 to 1995 to a Sharpsburg silty clay loam soil at rates sufficient to meet P or N requirements for corn and incorporated following application. After four years of corn production following the last compost application, P concentration, …

Congruent Weak Conformance, Ronald W. Brower

Theses and Dissertations

This research addresses the problem of verifying implementations against specifications through an innovative logic approach. Congruent weak conformance, a formal relationship between agents and specifications, has been developed and proven to be a congruent partial order. This property arises from a set of relations called weak conformations. The largest, called weak conformance, is analogous to Milner's observational equivalence. Weak conformance is not an equivalence, however, but rather an ordering relation among processes. Weak conformance allows behaviors in the implementation that are unreachable in the specification. Furthermore, it exploits output concurrencies and allows interleaving of extraneous output actions in the implementation. …

Modeling, Fabrication, And Optimization Of Niobium Cavities: Phase Ii Quarterly Report, Robert A. Schill Jr., Mohamed Trabia

Transmutation Sciences Materials (TRP)

Multipacting is one of the major loss mechanisms in rf superconductivity cavities for accelerators. This loss mechanism limits the maximum amount of energy/power supported by the cavities. Optimal designs have been identified in others’ studies. In practice, these designs are not easily manufactured. Chemical etching processes used to polish the cavity walls result in a nonuniform surface etch. A nonuniform surface etch will leave some unclean areas with contaminants and micron size particles. These significantly affect mutipacting. Further, a nonuniform etch will leave areas with damaged grain structure, which is not good for superconducting properties. Typically, the depth of chemical …

Automated Synthesis Of Generalized Reversible Cascades Using Genetic Algorithms, Martin Lukac, Mikhail Pivtoraiko, Alan Mishchenko, Marek Perkowski

Electrical and Computer Engineering Faculty Publications and Presentations

We propose an automated synthesis of Reversible logic (RL) circuits using Darwinian and Lamarckian Genetic Algorithms (GA). Our designs are in a form of cascades of generalized gates which generalize factorized Exclusive-Or-Sum-of-Products (ESOP) circuits. GA can be used to explore the problem space of combinational functions and here it is used to evolve reversible logic circuits. We emphasize the role of problem encoding - a well-designed encoding leads to improved results. Our method with well-encoded circuits is compared to standard method on classical benchmarks in GA, and shows good results for synthesis of both random functions and benchmark functions with …

Evolving Quantum Circuits And An Fpga-Based Quantum Computing Emulator, Goran Negovetic, Marek Perkowski, Martin Lukac, Andrzej Buller

Electrical and Computer Engineering Faculty Publications and Presentations

The goal of the PQLG group is to develop complete methodologies, software tools and circuits for quantum logic. Our interests are mainly in logic synthesis for quantum circuits and quantum system design [10]. Emulation of quantum circuits using standard reconfigurable FPGA technology and FPGA-based Evolvable Quantum Hardware, proposed here, are research areas not yet dealt with by other research groups. A parallel software simulator was presented in [13].