Engineering Commons^™

A Multiobjective Approach Applied To The Protein Structure Prediction Problem, Richard O. Day

Theses and Dissertations

Interest in discovering a methodology for solving the Protein Structure Prediction problem extends into many fields of study including biochemistry, medicine, biology, and numerous engineering and science disciplines. Experimental approaches, such as, x-ray crystallographic studies or solution Nuclear Magnetic Resonance Spectroscopy, to mathematical modeling, such as minimum energy models are used to solve this problem. Recently, Evolutionary Algorithm studies at the Air Force Institute of Technology include the following: Simple Genetic Algorithm (GA), messy GA, fast messy GA, and Linkage Learning GA, as approaches for potential protein energy minimization. Prepackaged software like GENOCOP, GENESIS, and mGA are in use to …

Compare And Complexity - When Is Compare Not Enough?, Chris E. Greiman

Theses and Dissertations

The purpose of this case study research is to determine the utility of COMPARE, the DoD approved software for conducting A-76 competitions, in the more complex world of public-private competition. COMPARE serves as the baseline for establishing cost factors, while two Air Force Depots are used as a basis of comparison. Research questions answered are: 1. What are the baseline cost comparison factors established in COMPARE? 2. What are the common cost factors found in the Air Force Depot public-private competitions? 3. What are the similarities and differences between the cost factors established in COMPARE and those used in the …

Charge And Spin Structure In Yba2cu3o6.35, Herbert A. Mook, Pengcheng Dai, Fatih Dogan

Materials Science and Engineering Faculty Research & Creative Works

Neutron scattering has been used to measure the charge and spin structure in the highly underdoped superconductor YBa₂Cu₃O_6.35. Incommensurate static charge ordering is found that remains at high temperatures. The magnetic pattern is complex with a resonance and incommensurate structure observed at low temperatures. The results clarify the role of striped phases in YBa₂Cu₃O_6+x superconductors.

Evaluation Of Modal Pushover Analysis: Sac Buildings Excluding Gravity Loads, Anil K. Chopra, Rakesh K. Goel

Civil and Environmental Engineering

No abstract provided.

Test Verification Of The Effect Of Stress Gradient On Webs Of Cee And Zee Sections, Benjamin W. Schafer, Cheng Yu

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

No abstract provided.

Acuta Enews March 2002, Vol 31, No. 3

ACUTA Newsletters

Leadership Award to Honor Ruth Michalecki

ACUTA Elections to Go Online

DC Update

Board Report

Writing and Selling the Plan

Welcome New Members

Positions Available

Definition And Evaluation Of Bus And Truck Automation Operations Concepts, H.-S. Jacob Tsao, Jan Botha

Faculty Publications

Traffic congestion will continue to worsen and likely worsen at a faster rate than ever. People throughput and freight throughput have become critical issues for California and the rest of the nation. PATH has been funding a one-year research project entitled “Definition And Evaluation of Bus And Truck Automation Operations Concepts,” proposed by the authors. This report summarizes the results of the research project achieved during the first six months. During those six months, we reviewed literature and developed operating concepts for both urban bus automation and inter-city truck automation. We also selected a small number of most promising operating …

Microelectronics Process Engineering At San Jose State University: A Manufacturing-Oriented Interdisciplinary Degree Program, Emily Allen, Stacy H. Gleixner, David W. Parent, Greg Young, Yasser Dessouky, Linda Vanasupa

Faculty Publications

San Jose State University's new interdisciplinary curriculum in Microelectronics Process Engineering is described. This baccalaureate program emphasizes hands-on thin-film fabrication experience, manufacturing methods such as statistical process control, and fundamentals of materials science and semiconductor device physics. Each course of the core laboratory sequence integrates fabrication knowledge with process engineering and manufacturing methods. The curriculum development process relies on clearly defined and detailed program and course learning objectives. We also briefly discuss our strategy of making process engineering experiences accessible for all engineering students through both Lab Module and Statistics Module series.

How Should Governments Address High Levels Of Natural Radiation And Radon--Lessons From The Chernobyl Nuclear Accident And Ramsar, Iran, S. M. Javad Mortazavi, M. Ghiassi-Nejad, Azam Niroomand-Rad, P. Andrew Karam, John R. Cameron

RISK: Health, Safety & Environment (1990-2002)

The authors discuss the high levels of natural background radiation in Ramsar, Iran, and offer data indicating that this has had little effect on the health of Ramsar's inhabitants. The authors then examine the implications their research could have for public health policy.

Smart Growth And Land Acquisition Priorities, New England Environmental Finance Center

Land Conservation

It is well-known and generally accepted that all undeveloped land in New England cannot forever be protected from development; nor would this be a desirable goal, as continued economic development and population growth are near certainties. For these and other reasons, private land trusts and government agencies generally use explicit criteria to prioritize their land acquisition activities and prospects.

Much land protection in New England and elsewhere, however, has occurred without substantial attention to such land use needs as fostering the best locations for where people will live, businesses will locate, and infrastructure will be built to avoid degrading resources. …

Exact Bounds On Sample Variance Of Interval Data, Scott Ferson, Lev Ginzburg, Vladik Kreinovich, Monica Aviles

Departmental Technical Reports (CS)

We provide a feasible (quadratic time) algorithm for computing the lower bound on the sample variance V of interval data. The problem of computing the upper bound on V is, in general, NP-hard. We provide a feasible algorithm that computes the upper bound on V for many reasonable situations.

Detecting And Locating Curved Cracks In Thin Plates By Lamb Wave Reflection: Validated Geometric Approach, Roberto A. Osegueda, Vladik Kreinovich

Departmental Technical Reports (CS)

Lamb waves propagate through a thin plate, and thus, provide a way of scanning this plate and detecting cracks and other faults. The equations describing these waves are rather complex, and, as a result, it is difficult to extract, from the received signal, the location of the fault. Recently, a new geometric approach has been proposed which allows, for linear cracks, to determine the presence and the location of a crack by using only the geometry of wave propagation. In this paper, we extend this approach to a more realistic case of curved cracks, and apply interval techniques to provide …

A Modal Pushover Analysis Procedure For Estimating Seismic Demands For Buildings, Anil K. Chopra, Rakesh K. Goel

Civil and Environmental Engineering

Developed herein is an improved pushover analysis procedure based on structural dynamics theory, which retains the conceptual simplicity and computational attractiveness of current procedures with invariant force distribution. In this modal pushover analysis (MPA), the seismic demand due to individual terms in the modal expansion of the effective earthquake forces is determined by a pushover analysis using the inertia force distribution for each mode. Combining these ‘modal’ demands due to the first two or three terms of the expansion provides an estimate of the total seismic demand on inelastic systems. When applied to elastic systems, the MPA procedure is shown …

Kinetics Of Mn(Ii) Oxidation By Leptothrix Discophora Ss1, Jinghao Zhang, Leonard W. Lion, Yarrow M. Nelson, Michael L. Shuler, William C. Ghiorse

Civil and Environmental Engineering

The kinetics of Mn(II) oxidation by the bacterium Leptothrix discophora SS1 was investigated in this research. Cells were grown in a minimal mineral salts medium in which chemical speciation was well defined. Mn(II) oxidation was observed in a bioreactor under controlled conditions with pH, O>sub>2, and temperature regulation. Mn(II) oxidation experiments were performed at cell concentrations between 24 mg/L and 35 mg/L, over a pH range from 6 to 8.5, between temperatures of 10°C and 40°C, over a dissolved oxygen range of 0 to 8.05 mg/L, and with L. discophora SS1 cells that were grown in the presence …

Thermodynamics And Bioenergetics, Yaşar Demirel, Stanley I. Sandler

Papers in Thermal Mechanics

Bioenergetics is concerned with the energy conservation and conversion processes in a living cell, particularly in the inner membrane of the mitochondrion. This review summarizes the role of thermodynamics in understanding the coupling between the chemical reactions and the transport of substances in bioenergetics. Thermodynamics has the advantages of identifying possible pathways, providing a measure of the efficiency of energy conversion, and of the coupling between various processes without requiring a detailed knowledge of the underlying mechanisms. In the last five decades, various new approaches in thermodynamics, non-equilibrium thermodynamics and network thermodynamics have been developed to understand the transport and …

Web Crippling And Bending Interaction Of Cold-Formed Steel Members, R. M. Schuster, J. A. Wallace, Roger A. Laboube

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

A new web crippling design approach has recently been adopted by the American Iron and Steel Institute and the North American Specification for the Design of Cold-Formed Steel Structural Members, November 9, 2001 Draft Edition (NAS, 2001). The current web crippling and bending interaction equations for single-web sections in the Specification (NAS, 2001) are based on the previous web crippling methods. As well, the moment component of the interaction equations was based on the previous reduced web strength method instead of the stress gradient approach that is now contained in the Specification (NAS, 2001). Based the available data found in …

An Experimental And Analytical Approach To Understanding The Dynamic Leaching From Municipal Solid Waste Combustion Residue, Kevin H. Gardner, Thomas L. Theis, Ramesh Iyer

Civil & Environmental Engineering

This paper describes an experimental technique involving the use of small columns for generating significant quantities of leachate data from municipal solid waste (MSW) solid residues within a relatively short amount of time. Data analysis using the discretized mass balance equations descriptive of the system results in best estimates of governing transport parameters that can, in turn, be used to predict the long-term release of leachable components (As, Cd, Cu, Fe, Ni, Pb, Zn, Ca, Mg, Na, K, Cl, SO4) from the solid matrix. Results indicate that both chemical solubility and physical transport are important factors affecting the flux of …

Cattle Handling Facilities: Planning, Components, And Layouts, José R. Bicudo, Samuel G. Mcneill, Larry W. Turner, Roy Burris, John Anderson

Agricultural Engineering Extension Publications

Cattle handling facilities are used to confine cattle safely and efficiently for close observation and to perform routine health and management procedures. Adequate facilities are an essential part of an efficient cattle operation for any producer who wants to improve marketing, cattle health, and production. A well-planned handling facility can help you save money by making easier practices such as preventive health management, pregnancy testing, implanting, controlling parasites, vaccinating, castrating, and dehorning.

A Reduced–Cost Mechanized System For Handling And Curing Mechanically–Harvested Burley Tobacco, Greg A. Camenisch, Larry G. Wells, Timothy D. Smith, George A. Duncan

Biosystems and Agricultural Engineering Faculty Publications

An experimental system was tested in which mechanically harvested burley tobacco plants placed onto steel slotted receivers were retrieved from a field, transported to a field curing structure, and placed onto the structure for air curing by a single worker. The system consisted of a tractor–towed, trailer mechanism that engaged and hoisted loads of approximately 360 burley plants of approximately 1 Mg mass. Ten slotted steel rails, 3.05 m long, holding 36 notched plants were placed onto parallel wooden beams suspended at a height of 2.13 m by wooden posts set in the ground. Burley tobacco was cured in this …

A Portable Rainfall Simulator For Plot–Scale Runoff Studies, J. Byron Humphry, Tommy C. Daniel, Dwayne R. Edwards, Andrew N. Sharpley

Biosystems and Agricultural Engineering Faculty Publications

Rainfall simulators have a long history of successful use in both laboratory and field investigations. Many plot–scale simulators, however, have been difficult to operate and transport in the field, especially in remote locations where water or electricity is unavailable. This article describes a new rainfall simulator that is relatively easy to operate and transport to and from the field while maintaining critical intensity, distribution, and energy characteristics of natural rainfall. The simulator frame is constructed from lightweight aluminum pipe with a single 50 WSQ nozzle centered at a height of 3 m (9.8 ft). An operating nozzle pressure of 28 …

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 18, Number 6, March 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.

Efficient Modeling Of Discontinuities And Dispersive Media In Printed Transmission Lines, R. Araneo, Chen Wang, Xiaoxiong Gu, James L. Drewniak, S. Celozzi

Electrical and Computer Engineering Faculty Research & Creative Works

The finite-difference time-domain method is applied to the analysis of transmission lines on printed circuit boards. The lossy, dispersive behavior of the dielectric substrate is accurately accounted for by means of several algorithms whose accuracy is discussed and compared. Numerical results are validated by comparisons with measurements and an equivalent circuit of slot in the ground plane is proposed.

Analytical Derivation Of A Coupled-Circuit Model Of A Claw-Pole Alternator With Concentrated Stator Windings, Hua Bai, Steven Pekarek, Jerry L. Tichenor, Walter Eversman, Duane J. Buening, Gregory R. Holbrook, Michael L. Hull, Ronald J. Krefta, Steven J. Shields

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A lumped-parameter coupled-circuit model of a claw-pole alternator is derived. To derive the model, analytical techniques are used to define a three-dimensional (3-D) Fourier-series representation of the airgap flux density. Included in the series expansion are the harmonics introduced by rotor saliency, concentrated stator windings, and stator slots. From the airgap flux density waveform, relatively simple closed-form expressions for the stator and rotor self- and mutual-inductances are obtained. The coupled-circuit model is implemented in the simulation of an alternator/rectifier system using a commercial state-model-based circuit analysis program. Comparisons with experimental results demonstrate the accuracy of the model in predicting both …

Effect Of Ph And Gas-Phase Ozone Concentration On The Decolorization Of Common Textile Dyes, Craig D. Adams, Steven Gorg

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This paper presents the results of a laboratory study on the effect of pH (2, 5, and 9) and gas-phase ozone concentration (1, 7, and 11 wt. %) on the decolorization efficiency via ozonation for seven common textile dyes. Higher gas-phase ozone concentrations resulted in higher decolorization rates due to more rapid ozone transfer. Higher gas-phase ozone concentration, however, was also observed to have a positive, neutral, or negative effect on ozone dose requirements for different dyes. In general, greater ozone utilization efficiency was achieved at lower pH levels where direct ozone reactions predominate. It was observed that because ozonation …

Experimental Vibration Analysis Of Inflatable Beams For An Afit Space Shuttle Experiment, Thomas G. Single

Theses and Dissertations

This study investigated the use of MEMS based devices to control the boundary layer separation from a circular cylinder in cross flow. Velocity profiles were measured experimentally in a low speed wind tunnel. Momentum thickness was measured as the primary way to determine a change in the flow field. The goal was to determine the angular location and frequency of operation that would provide an effect on the boundary layer of the cylinder. A 25% reduction of momentum loss in the cylinder wake was detected with an optimal angle of 69 degrees and an optimal frequency of operation equal to …

Broadcast Vs Precise Gps Ephemerides: A Historical Perspective, David L. M. Warren

Theses and Dissertations

In most recent years, both high-resolution imagery systems and images were only available to military and national security organizations. Distinctive changes within the commercial image industry allowed space-borne pioneers to provide high-resolution images. Space-borne Image Company's Ikonos satellite provides a 1-meter resolution for the past 3 years. Current development of .5-meter resolution will be offered in the near future. Access of these images is available in ground stations located worldwide in different regions. Studies have shown that these high quality images are eye-catching and may serve a purpose through its design; on contrary high cost and accessibility does not met …

The Investigation Of Hypervelocity Gouging, David J. Laird

Theses and Dissertations

The slipper/rail interface of a hypervelocity rocket sled is subject to immense forces due to dynamic loads and impact of the slipper with the rail, and tremendous heating due to aerodynamic and frictional effects is produced at the interface. Under these severe loading conditions, the material in the rail will sometimes experience large non-linear deformations known as gouging. Hydrocodes are computational solvers designed to handle such non-linear, large deformation, high shock, hydrodynamic applications. The ability of the hydrocode CTH to handle gouge modeling is considered, as well as the manner in which temperature environments affect deformation and plastic strain. The …

Design And Fabrication Of Micro-Electro-Mechanical Structures For Tunable Micro-Optical Devices, Michael C. Harvey

Theses and Dissertations

Tunable micro-optical devices are expected to be vital for future military optical communication systems. In this research I seek to optimize the design of a microelectromechanical (MEM) structure integrated with a III-V semiconductor micro-optical device. The resonant frequency of an integrated optical device, consisting of a Fabry-Perot etalon or vertical cavity surface emitting laser (VCSEL), may be tuned by applying an actuation voltage to the MEM Flexure, thereby altering the device's optical cavity length. From my analysis I demonstrate tunable devices compatible with conventional silicon 5V integrated circuit technology. My design for a Fabry-Perot etalon has a theoretical tuning range …

Fretting Fatigue Behavior Of A Titanium Alloy Ti-6al-4v At Elevated Temperature, Onder Sahan

Theses and Dissertations

The purpose of this research is to investigate the fretting fatigue behavior of the titanium alloy Ti-6Al-4V at elevated temperature is investigated. Fretting and plain fatigue experiments are conducted at 260 °C. Crack initiation location and crack initiation orientation is measured and fretting and plain fatigue life data of the specimens from these tests are obtained. Fatigue parameters capable of predicting the number of cycles to specimen failure, the crack location and the crack orientation along the contact surface are analyzed. The parameters are calculated by using the computed stresses and strains obtained from the finite element analysis. The mechanisms …

An Analytical Study Of T-38 Drag Reduction In Tight Formation Flight, Eugene H. Wagner Jr.

Theses and Dissertations

This thesis explores the benefits of flying in a tight formation, mimicking the natural behavior of migratory birds such as geese. The first phase of the research was to determine an optimal position for the wingman of a tight formation flight of T-38 Talon aircraft using the HASC95 vortex lattice code. A second wingman was then added to determine the benefit derived by increasing formation size. The second wingman was predicted to derive an even greater induced drag benefit than the first wingman for T-38s operating at Mach 0.54 at a 10,000-foot altitude. The predicted values were 17.5% savings for …