Engineering Commons^™

Carbon Frp Strengthening Of Doubly Curved Precast Pc Shell, M. Barboni, A. Benedetti, Antonio Nanni

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

In this paper a recent rehabilitation project completed in Italy using carbon fiber reinforced plastic (CFRP) unidirectional sheets is examined. This technology was selected for the strengthening of a doubly curved, precast, prestressed concrete (PC) shell. The shell was part of the roof of an industrial building and had experienced severe localized damage due to accidental heat radiating from a flue. The selection of the CFRP system involved the screening of different repair procedures with relation to the constraints imposed by the owner: limited disturbance to the industrial process, safety of the occupants, low cost, and durability. In addition, the …

An Object-Based Evolutionary Algorithm For Solving Rectangular Piece Nesting Problems, Kanchitpol Ratanapan, Cihan H. Dagli

Engineering Management and Systems Engineering Faculty Research & Creative Works

Nesting problems have been tackled by researchers using a vast number of algorithms in the past. Most of the algorithms, however, need to perform on a one-dimensional space. Therefore, the problem must be transformed into a one-dimensional space problem similar to the travelling salesman problem. Consequently, loss of solutions due to the dimensional reduction may occur. In this study, an object-based evolutionary algorithm for rectangular piece nesting problems is proposed. This methodology is created on truly two-dimensional space, allowing new mechanisms (i.e., individual representation, initialization, etc.) and new object-based genetic operators (i.e., hill-climbing, mutation, and recombination operators) to perform effectively …

Performance-Based Testing Of Chemical Stabilizers, Thomas M. Petry

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Chemical stabilizing agents have been introduced that have performed in field applications to improve the behavior of earth materials. The same agents and materials subjected to standardized laboratory tests have often resulted in no improvement. For example, the tests often require pulverization of materials to finer states than are needed in the field or may require remolding when field applications are done in situ, as with injection applications. Some of the physical tests do not place treated materials in a situation resembling conditions in the field, yet they are applied to determine the use of these agents. The experiences of …

Spherical Harmonics - Finite Element Treatment Of Neutron Transport In Cylindrical Geometry, Hatem Khouaja, D. Ray Edwards, Nicholas Tsoulfanidis

Nuclear Engineering and Radiation Science Faculty Research & Creative Works

A variational spherical harmonics (DPN) method is used in conjunction with the finite element method to solve the transport of neutron beams. The method is developed for finite axisymmetric cylindrical geometry. In this model, the angular distribution along the path of neutron travel is separated into two sub-ranges of the forward and the backward moving particles. The system of the model equations is cast in terms of an even and an odd vector analogue to the even-parity transport technique. The finite element method is applied in space to solve the resulting coupled system of equations. A source-free cylinder with specified …

Sensitivities Of Report Writing For Weak-Rock Projects, Allen W. Hatheway

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Weak rock is the natural realm of geological engineers and engineering geologists. We are the best equipped geotechnical professionals to deal effectively with these difficult and generally complex earth materials, and we have the obligation to produce the most informative technical reports possible in weak-rock assignments. Because of the strength-related problems of weak rock, we should remain cognizant of the need to emphasize several aspects of our reports. For this purpose weak rock occurs because of one or more strength-degrading considerations: 1. Weak to deleterious lithology; the latter imparting damaging characteristics to concretes and to rock utilized as rip-rap and …

Relative Permeability Effects On The Migration Of Steamflood Saturation Fronts, A. Erkal, Daopu Thompson Numbere

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The effects of various relative permeability-saturation relationships on the movement of water saturation fronts during steam flooding is investigated. Empirical correlations, curve fitting and spline interpolation functions are used to represent the relative permeability data. The effects of these correlations on water saturation movement and ultimately on oil recovery performance are compared. It was observed that only the spline function is able to adequately represent a given set of data throughout its saturation range. All the other correlations fit the given data well only at high water saturations and fit poorly at the low saturations. Furthermore, the correlations converge at …

Artificial Neural Network Based Model For Computation Of Injection Mould Complexity, Rawin Raviwongse, Venkat Allada

Engineering Management and Systems Engineering Faculty Research & Creative Works

The cost of injection mould construction depends primarily on the mould complexity. The ability to estimate the mould complexity before releasing the final drawings for construction purposes will greatly help the designers to understand the implications of their design on cost. Mould complexity depends on several factors such as part geometry, parting line, materials, and number of cavities per mould. In most industries, the mould complexity evaluation is performed manually based on past experiences of mould makers. Faced with a shortage of experienced mould makers, there is a pressing need for development of computer-aided tools for mould complexity evaluation. In …

Self-Assessment Of Total Quality Management Programs, Hung Yi Wu, Henry Allen Wiebe, John Politi

Engineering Management and Systems Engineering Faculty Research & Creative Works

Total quality management (TQM) has been increasingly accepted as a management philosophy. Criteria such as those contained in the Malcolm Baldrige National Quality Award (MBNQA) often guide TQM implementation. However, reports indicate that fully assessing TQM efforts is difficult and hiring experts to help with this task is expensive. Using survey instruments is an attractive alternative to full-scale assessment. Despite the availability of many papers covering organizational performance assessment, few instruments specifically address TQM evaluation. Furthermore, none of the TQM assessment instruments has been subjected to rigorous validation; thus, only modest confidence can be placed in results obtained from their …

An Analog Integrated Circuit For Continuous-Time Gain And Offset Calibration Of Sensor Arrays, Yu Ming Chiang, John G. Harris

Electrical and Computer Engineering Faculty Research & Creative Works

Parameter variations cause unavoidable nonuniformities in Infra-Red Focal Plane Arrays and other integrated sensors. Since these nonuniformities change slowly with time, calibrating sensors one-time only is not suitable-much more frequent calibration is required. We have developed an algorithm that continually calibrates an array of sensors that contain gain and offset variations. This algorithm has been mapped to analog hardware and designed and fabricated with a 2um CMOS technology. Measured results from the chip show that the system achieves invariance to gain and offset variations of the input signal.

Neutron Transmutation Doping As An Experimental Probe For Cuzn In Znse, Edward D. Wheeler, Jack L. Boone, J. W. Farmer, H. R. Chandrasekhar

Electrical and Computer Engineering Faculty Research & Creative Works

Nuclear transmutation is employed in an investigation of copper doping in ZnSe. Copper atoms are introduced at zinc sites in ZnSe after crystal growth processes are complete. Since the copper dopants are introduced after growth, far from equilibrium, they are less able to form complexes with other dopants or lattice defects as they may do when present during crystal growth. Initial results are consistent with CuZn being involved in the copper red and copper green emissions in ZnSe but not in the if exitonic emission. © 1997 American Institute of Physics.

Tomographic And Particle Tracking Studies In A Liquid-Solid Riser, Shantanu Roy, Jinwen Chen, Sailesh B. Kumar, M. (Muthanna) H. Al-Dahhan, M. P. Duduković

Chemical and Biochemical Engineering Faculty Research & Creative Works

A Liquid-Solid Circulating Fluidized Bed is a Potential Reactor of Interest in a Variety of Industrial Processes, Such as Petroleum Refining, and in the Synthesis of Fine Chemicals, Petrochemicals, and Foodstuffs. Rapid Deactivation of the Solid Catalyst in These Processes Necessitates Regeneration and Regulation of the Solids into the Riser Section in Which the Principal Reaction is Accomplished. in This Study We Show that Computer-Automated Radioactive Particle Tracking (CARPT) Can Be Used to Obtain Solids Velocity Patterns in the Riser and that Backflow of Solids Exists at the Tested Liquid Velocities. Γ-Ray Computed Tomography (CT) Reveals Slightly Higher Solids Concentrations …

Assessment Of The Effects Of High-Pressure Operation On The Liquid-Solid Mass-Transfer Coefficient In Trickle-Bed Reactors, M. (Muthanna) H. Al-Dahhan, W. Highfill, M. Friedman

Chemical and Biochemical Engineering Faculty Research & Creative Works

Trickle-Bed Reactors Are Used Widely in Industry and Are Usually Operated at High Pressure. All the Studies on Liquid-Solid Mass Transfer in Such Reactors Were Performed under Atmospheric Pressure And, Hence, the Empirical Correlations for Liquid-Solid Mass-Transfer Coefficients (K1s and K1sa) Were Developed based on Atmospheric Data. However, These Correlations Incorporate One or More of the Parameters Affected by Pressure (E.g., Liquid Holdup, Catalyst Wetting Efficiency, Pressure Drop, Gas Density). in This Work the Effects of High Pressure and High Gas Flow Rates on the Predicted Coefficients using Some of These Correlations Are Evaluated. It is Shown that There Are …

High-Pressure Trickle-Bed Reactors: A Review, Muthanna H. Al-Dahhan, Faical Larachi, Milorad P. Dudukovic, Andre Laurent

Chemical and Biochemical Engineering Faculty Research & Creative Works

A Concise Review of Relevant Experimental Observations and Modeling of High-Pressure Trickle-Bed Reactors, based on Recent Studies, is Presented. the Following Topics Are Considered: Flow Regime Transitions, Pressure Drop, Liquid Holdup, Gas-Liquid Interfacial Area and Mass-Transfer Coefficient, Catalyst Wetting Efficiency, Catalyst Dilution with Inert Fines, and Evaluation of Trickle-Bed Models for Liquid-Limited and Gas-Limited Reactions. the Effects of High-Pressure Operation, Which is of Industrial Relevance, on the Physicochemical and Fluid Dynamic Parameters Are Discussed. Empirical and Theoretical Models Developed to Account for the Effect of High Pressure on the Various Parameters and Phenomena Pertinent to the Topics Discussed Are Briefly …

Limitations And Dynamics Imposed On Multicomponent Batch Distillation By Tray Hydraulics, Keith G. Tomazi

Chemical and Biochemical Engineering Faculty Research & Creative Works

Batch distillation models incorporating a complete set of hydraulic relations, energy balances, and tray efficiencies and simpler models based upon constant molar holdup and zero holdup (the Rayleigh equation) were used to obtain distillation curves and optimal reflux policies. The approach to hydraulic limitations was monitored in the complete hydraulic model. The results indicate that during a multicomponent batch distillation the combination of the changes in the liquid composition and liquid flow rates causes the molar holdup on the trays to vary with time and, consequently, the characteristic time constant of the trays changes. The predicted composition profiles for descriptions …

A Small-Angle Neutron Scattering Study Of Γ-Crystallins Near Their Isoelectric Point, Paul Petitt, Michael Eugene Edwards, Daniel Forciniti

Chemical and Biochemical Engineering Faculty Research & Creative Works

In this paper, a small-angle neutron scattering study of γII-crystallins near their isoelectric point is presented. The experiments were carried out using protein concentrations of 5.7-85.7 mg/ml at temperatures in the range 11-60°C. The experimental data were analyzed using an ellipsoidal model for intraparticle correlations and the mean spherical approximation for interparticle correlations. Our studies revealed that γII-crystallins have a thick hydration layer, which is possibly due to the special arrangement of polar and ionic groups on their surface. The temperature scan shows that, as a result of relatively strong attractive forces, clusters of two, three, or higher oligomers are …

Eigenvalue And Eigenvector Determination For Damped Gyroscopic Systems, D. P. Malone, Don L. Cronin, Timothy W. Randolph

Mechanical and Aerospace Engineering Faculty Research & Creative Works

No abstract provided.

Effect Of Variable-Ph Landfill Leachate On A Carbonate Rock Aggregate, William L. Niemann, Allen W. Hatheway

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Carbonate rock aggregate is commonly used as drainage stone in leachate collection systems of RCRA Subtitle D landfills. U.S. EPA technical guidance for waste containment facilities states that excessive carbonate in drainage stone may result in dissolution and clogging at sites of reprecipitation (Daniel and Koerner, 1993, p. 197). Unfortunately, this theoretical concern does not appear to be confirmed by any experimental evidence with typical landfill leachate or documented instances of clogging at typical Subtitle D landfills. This paper describes a practical laboratory experiment that measured the effects of landfill leachate - maintained at three distinct pH levels - on …

Chemical Durability Of Lead-Oxide-Based, Thick-Film Binder Glasses, Douglas M. Mattox, Joshua H. Robinson

Materials Science and Engineering Faculty Research & Creative Works

Lead-oxide-bearing glasses are incompatible with aluminum nitride metallization's, and federal legislation is recommending their replacement in thick-film electronics and labeling. To evaluate alternatives, the benchmark chemical durability's of the lead borosilicate and lead aluminate thick-film binder glasses have been determined. Aluminum oxide (Al2O3) benefits water durability moderately, acid durability substantially, and basic durability indistinguishably. The rate of attack in water is approximately two orders of magnitude greater than for soda-lime glass. The thermal contractions of the glasses are compatible. An apparent, spontaneous phase separation in the Al2O3-free glass is suppressed by Al2O3 that is included as a batch component.

Scaling Parallels In The Non-Debye Dielectric Relaxation Of Ionic Glasses And Dipolar Supercooled Liquids, David L. Sidebottom, Peter F. Green, Richard K. Brow

Materials Science and Engineering Faculty Research & Creative Works

We compare the dielectric response of ionic glasses and dipolar liquids near the glass transition. Our work is divided into two parts. In the first section we examine ionic glasses and the two prominent approaches to analyzing the dielectric response. The conductivity of ion-conducting glasses displays a power law dispersion σ(ω)∞ωn, where n≈0.67, but frequently the dielectric response is analyzed using the electrical modulus M*(ω) = 1/ε*(ω), where ε*(ω) = ε(ω) - iσ(ω)/ω is the complex permittivity. We reexamine two specific examples where the shape of M*(ω) changes in response to changes in (a) temperature and (b) ion concentration, to …

Multiobjective Optimization Design With Pareto Genetic Algorithm, Franklin Y. Cheng, Dan Li

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This paper presents a constrained multiobjective (multicriterion, vector) optimization methodology by integrating a Pareto genetic algorithm (GA) and a fuzzy penalty function method. A Pareto GA generates a Pareto optimal subset from which a robust and compromise design can be selected. This Pareto GA consists of five basic operators: reproduction, crossover, mutation, niche, and the Pareto-set filter. The niche and the Paretoset filter are defined, and fitness for a multiobjective optimization problem is constructed. A fuzzy-logic penalty function method is developed with a combination of deterministic, probabilistic, and vague environments that are consistent with GA operation theory based on randomness …

A 50 Kilowatt Distributed Grid-Connected Photovoltaic Generation System For The University Of Wyoming, Badrul H. Chowdhury, S. Muknahallipatna, T. Dinwoodie, D. Shugar, J. J. Cupal, J. C. Hamann

Electrical and Computer Engineering Faculty Research & Creative Works

The University of Wyoming (UW) campus (USA) is serving as the site for a 50 kilowatt solar photovoltaic (PV) power system. Three sub-systems were sited and built on the UW campus in 1996. The first sub-system, a 10 kW roof-integrated system of PV roof tiles is located on the roof of the Engineering Building. The second sub-system-a 5 kW rack-mounted, ballasted PV system is on a walkway roof of the Engineering building. The third sub-system is a 35 kW shade structure system and is located adjacent to the parking lot of the University's football stadium. The three sub-systems differ in …

Reinforcement Of Web Openings In Cold-Formed Steel Members, Erika Kirsten Nelson

Masters Theses

"To expand on previous research concerning perforated cold-formed steel web elements, an experimental investigation was conducted to examine the influence of reinforcement on the behavior and strength of single web flexural members with web openings. In current design practice, reduction factors are applied to the strength equations to account for the debilitating effect of web openings. This reduction in capacity may lead to the selection of a greater member thickness or depth than would be required of a solid web member. A more economical approach may be to reinforce the web in the proximity of the opening to increase the …

Asynchronous Distance Learning Technology: The Instructor's Perspective, Earl Alexander Evans

Masters Theses

"Advances in communications, computer technology and human-computer interfaces have enabled concurrent advances in Web-based education. A number of case studies concerning applications of Web-based education for both distance learning and on-campus programs have been published. Primarily, these studies have focused on individual assessments of the Web-based technologies. In addition, these published studies have generally highlighted the successes while little discussion about failed attempts has been presented in the literature.

In contrast, this thesis provides a broad-based assessment of applied Web technology for higher education. This research was conducted via a survey completed by twenty five university and college faculty from …

Bridge Engineering For The Elementary Grades, Douglas R. Carroll

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A one-hour presentation was developed to get elementary school students interested in engineering. The presentation begins with the students building six feet long, structurally sound bridge which they can crawl across. A pictorial presentation helps them learn to identify some of the different types of bridges: truss, stone arch, steel arch, concrete girder, cable-stayed, and suspension. They are introduced to the fundamental engineering concepts of tension and compression. These concepts are reinforced by demonstrating that if a tension member is replaced with a chain then the bridge is still strong, but if a compression member is replaced with a chain …

Miniaturized Isfet Glucose Sensor Including A New Structure Actuation System, Chang-Soo Kim, Hwa-Il Seo, Chae-Hyang Lee, Byung-Ki Sohn

Electrical and Computer Engineering Faculty Research & Creative Works

A new principle of an amperometric actuation technique was incorporated in the ISFET glucose sensor. The ISFET is fabricated by the CMOS process and the platinum working electrode is deposited by the lift-off process. A sensor with a specially designed ladder type working electrode exhibits improved operation in response time, response magnitude and detection range. An expectation concerning the reduction of sensor size is also discussed.

Constrained Moments Simulation Of Healthcare Capital Acquisitions, A. Narsing, Samuel Frimpong, J. Whiting

Mining Engineering Faculty Research & Creative Works

Summary form only as given. Two analytical techniques which evaluate capital acquisitions in healthcare are the method of generating system moments and Monte Carlo simulation. Generating system moments enables the user to determine an estimate of the expected cost from a user-supplied function. Furthermore, the user can determine, from a variance component analysis, the sensitivity of the user-supplied function to marginal changes in the random variables by expanding the function about its mean using the Taylor series expansion to the second order. Calculating the magnitude of partial derivatives of each random variable with respect to the user-supplied function indicates the …

Adaptive Critic Design In Learning To Play Game Of Go, R. Zaman, Danil V. Prokhorov, Donald C. Wunsch

Electrical and Computer Engineering Faculty Research & Creative Works

This paper examines the performance of an HDP-type adaptive critic design (ACD) of the game Go. The game Go is an ideal problem domain for exploring machine learning; it has simple rules but requires complex strategies to play well. All current commercial Go programs are knowledge based implementations; they utilize input feature and pattern matching along with minimax type search techniques. But the extremely high branching factor puts a limit on their capabilities, and they are very weak compared to the relative strengths of other game programs like chess. In this paper, the Go-playing ACD consists of a critic network …

Backpropagation Of Accuracy, Donald C. Wunsch, M. Yu Senashova, Alexander N. Gorban

Electrical and Computer Engineering Faculty Research & Creative Works

We solve the problem: how to determine maximal allowable errors, possible for signals and parameters of each element of a network, proceeding from the condition that the vector of output signals of the network should be calculated with given accuracy? "Backpropagation of accuracy" is developed to solve this problem

Effect Of Cl Incorporation On The Performance Of Amorphous Silicon Thin Film Transistor, Jong Hyuni Choi, Chang-Soo Kim, Sung Ki Kim, Jin Jang

Electrical and Computer Engineering Faculty Research & Creative Works

No abstract provided.

High Order Orthogonal Tensor Networks: Information Capacity And Reliability, Donald C. Wunsch, Y. M. Mirkes, Alexander N. Gorban

Electrical and Computer Engineering Faculty Research & Creative Works

Neural networks based on construction of orthogonal projectors in the tensor power of space of signals are described. A sharp estimate of their ultimate information capacity is obtained. The number of stored prototype patterns (prototypes) can many times exceed the number of neurons. A comparison with the error control codes is made