Engineering Commons^™

Summer 1994, 90.9 Wmpg Fm

WMPG Program Guides

No abstract provided.

Optical Computing: Introduction By The Feature Editors, Scott Hinton, Bernard Soffer, Frank A.P. Tooley, Ken-Ichi Yukimatsu

Electrical and Computer Engineering Faculty Publications

This feature of Applied Optics: Information Processing on optical computing comprises thirty papers. Most of the papers evolved from papers presented at the Fifth Topical Meeting on Optical Computing held in March 1993 in Palm Springs, California.

Acceptable Risk: A Conceptual Proposal, Baruch Fischhoff

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

Challenging the "de minimis risk" concept, Dr. Fischhoff argues that risks ought not to be considered apart from a particular technology's benefits. He argues, too, that the acceptability of particular kinds of risks should not be determined without considering the views of all persons who may be exposed. Finally, building upon the "reasonable person" construct, he suggests ways those goals might be achieved.

Scheduling Of Unstructured Communication On The Intel Ipsc/860, Jhy-Chun Wang, Sanjay Ranka

College of Engineering and Computer Science - Former Departments, Centers, Institutes and Projects

In this paper we present several algorithms for decomposing all-to-many personalized communication into a set of disjoint partial permutations. These partial permutations avoid node contention as well as link contention. We discuss the theoretical complexity of these algorithms and study their effectiveness both from the view of static scheduling and from runtime scheduling. Experimental results for our algorithms are presented on the iPSC/860.

Block Qpsk Modulation Codes With Two Levels Of Error Protection, Robert H. Morelos-Zaragoza, Shu Lin

Faculty Publications

A class of block QPSK modulation codes for unequal error protection (UEP) is presented. These codes are particularly suitable either for broadcast channels or for communication systems where parts of the information messages are more important than others. An example of the latter is coded speech transmission. Not much is known on the application of block UEP codes in combined coding and modulation schemes. We exhibit a method to combine binary linear UEP (LUEP) block codes of even length, using a Gray mapping, with a QPSK signal set to construct efficient block QPSK modulation codes with nonuniform error protection capabilities …

Constraints On Initial Ahs Deployment And The Concept Definition Of A Shuttle Service For Ahs Debut, Jacob Tsao

Faculty Publications

Highway automation and its evolution involve a multitude of systems issues. Particularly important and difficult in defining a deployment sequence is the very first step, i.e. the first user service involving fully automated freeway driving. However, this importance and the difficulty imply that many factors may severely constrain the initial deployment. After discussing the paramount importance of initial AHS deployment, this paper points out major high-level issues and constraints. Any realistic deployment strategy must take into consideration gradual technology maturation, introduction of new driver role and diminishing conventional driver role for automated driving, high cost of early-generation automation-equipped vehicles, gradual …

University Of Texas At Tyler Catalog, 1994-1996, University Of Texas At Tyler

Catalogs

Archives Space instance: https://archivesspace.uttyler.edu/repositories/2/archival_objects/22365

Error Recovery In Intelligent Robotic Workcells, R. D. Borchelt, Sema E. Alptekin

Industrial and Manufacturing Engineering

This paper focuses on the requirements for achieving automated diagnosis and error recovery in a robotic assembly cell. Untended robust operation is the goal which is discussed, and the use of a knowledge-base oriented diagnostic/control system to support on-line error recovery is advocated. It is proposed that error recovery attempts should be made, not only based on information gathered by system sensors, but also by using additional cell-specific knowledge pertaining to recovery strategies. Recovery attempts are to be made even in the absence of complete diagnosis, in order to gather additional information. A control structure developed to implement this approach …

Dual-Level Approach For Seismic Design Of Asymmetric-Plan Buildings, Rakesh K. Goel, Anil K. Chopra

Civil and Environmental Engineering

Buildings should be designed to resist moderate ground motion without structural damage and resist intense ground motion with controlled damage. However, most codes do not consider both these requirements explicitly and specify a single design earthquake that generally corresponds to intense ground motion. Investigated in this study is the response of one-story, asymmetric-plan systems designed according to torsional provisions of seismic codes to the two levels of ground motions with the objective of evaluating whether such systems satisfy these requirements. The presented results demonstrate that such systems may not remain elastic during moderate ground motion resulting in structural damage and …

An Exploratory Study Of Hypermedia Support For Problem Decomposition, Robert P. Minch, Gary I. Green

IT and Supply Chain Management Faculty Publications and Presentations

Empirical hypermedia research has concentrated on usability rather than utility, and the research on utility has focused on information access as opposed to problem solving and decision making in organizations. This study, based on problem reduction theory, uses a hypermedia prototype system to support decision processes for solving a financial analysis problem. An exploratory laboratory experiment was conducted to study the feasibility of the prototype for hypermedia support of decision making. The process tracing techniques used suggest that a cognitive map of a decision maker's thought process may be constructed. Results offer a great deal of promise in the use …

Concrete Beam Design Optimization With Genetic Algorithms, Siripong Malasri, D. A. Halijan, M. L. Keough

Journal of the Arkansas Academy of Science

This paper demonstrates an application of the natural selection process to the design of structural members. Reinforced concrete beam design is used as the example to show how various chromosomes representing a design solution can be formulated. Fitter chromosomes (or better solutions) have a better chance of being selected for cross over; this in turn creates better generations. Random mutation is used to enhance the diversity of the population. The evolution progresses through several generations, and the best solution is then used in the design. The method gives reasonable results, but sometimes a local (as opposed to the global) optimized …

Application Of Machine Learning Principles To Modeling Of Nonlinear Dynamic Systems, Murray R. Clark

Journal of the Arkansas Academy of Science

A method for the development of mathematical models for dynamic systems with arbitrary nonlinearities from measured data is described. The method involves the use of neural networks as embedded processors in dynamic system simulation models. The technique is demonstrated through generation of models for anharmonic oscillators described by the Duffing Equation and the Van der Pol Equation from measured input/output data. It is shown that high quality models of these systems can be developed using this technique which are efficient in terms of model size. Using neural networks as embedded processors, accurate models of the Duffing Oscillator and the Van …

On A Class Of Optimal Nonbinary Linear Unequal-Error-Protection Codes For Two Sets Of Messages, Robert H. Morelos-Zaragoza, Shu Lin

Faculty Publications

Several authors have addressed the problem of designing good linear unequal error protection (LUEP) codes. However, very little is known about good nonbinary LUEP codes. We present a class of optimal nonbinary LUEP codes for two different sets of messages. By combining t-error-correcting ReedSolomon (RS) codes and shortened nonbinary Hamming codes, we obtain nonbinary LUEP codes that protect one set of messages against any t or fewer symbol errors and the remaining set of messages against any single symbol error. For t ≥ 2, we show that these codes are optimal in the sense of achieving the Hamming lower bound …

The Importance Of Considering Size Effect Along The Cutting Edge In Predicting The Effective Lead Angle For Turning, William J. Endres, Daniel Waldorf

Industrial and Manufacturing Engineering

The concept of an effective orthogonal cutting edge in turning is considered. The orientation of this edge in the radial-longitudinal plane, as commonly modeled through an effective lead angle, is studied. The methods of effective lead angle prediction used in numerous previously developed force models are plagued with large errors over ranges of process inputs, in particular feed rate and depth of cut. Four previously developed methods of effective lead angle prediction are reviewed and compared to a new method presented here. This new method accounts for the size effect as introduced through the variation in chip thickness along the …

Journal Of Engineering Education Round Table: Reflections On The Grinter Report, James G. Harris, Eugene M. Deloatch, William R. Grogan, Irene C. Peden, John R. Whinnery

Electrical Engineering

The Round Table is a new presentation format for the Journal of Engineering Education. The purpose of the Round Table is to present the comments of several distinguished individuals about a topic as well as their responses to the comments offered by their colleagues. For the initial Journal of Engineering Education Round Table we asked for reflections about the Grinter Report, published in September 1955.

After a brief introduction to the topic of discussion, the invited participants present their views, and, then, respond to the remarks of their colleagues. The goal is two-fold: to present a spectrum of views on …

Bulletin - Winter, 1994, Civil Aviation Medical Association

Browse all Civil Aviation Medical Association Newsletters

A 24 page newsletter of the Civil Aviation Medical Association. The newsletter provided news about civil aviation medicine and information related to the organization.

Adsorption-Dissolution Reactions Affecting The Distribution And Stability Of Coii Edta In Iron Oxide-Coated Sand, James E. Szecsody, John M. Zachara, Patrick Bruckhart

United States Department of Energy: Publications

The time-variant chemical behavior of Co^IIEDTA (and other metal-EDTA complexes) was investigated in suspensions of iron oxide-coated sand to identify equilibrium and kinetic reactions that control the mobility of Me^IIEDTA complexes in subsurface environments. Batch experiments were conducted to evaluate the adsorption as a function of pH, concentration, and time and to quantify the rate-controlling step(s) of dissolution of the iron oxide by EDTA complexes. Ionic Co²⁺ exhibited typical cation-like adsorption, whereas Me^IIEDTA adsorption was ligand-like, increasing with decreasing pH. Adsorption isotherms for all reactive species exhibited Langmuir behavior, with site saturation occurring …

Interaction Of Hydrophobic Organic Compounds With Mineral-Bound Humic Substances, Ellyn M. Murphy, John M. Zachara, Steven Smith, Jerry Phillips, Thomas Wletsma

United States Department of Energy: Publications

The sorption of hydrophobic organic compounds (HOC) on mineral-associated peat humic acid (PHA) was evaluated under different pH and electrolyte regimes. Relative size distribution measurements indicated that PHA was “coiled” in solution at high ionic strength (I) and elongated at low I. The sorption of PHA to hematite and kaolinite varied with I and electrolyte cation, suggesting that the configuration of the humic acid in solution influenced its structure on the mineral surface. The sorption maxima for PHA on kaolinite indicated that PHA occupies twice the mineral surface area at low I (0.005) as that observed at …

Light, Chlorophyll, Carboxylase Activity And Co2 Fixation At Various Depths In The Chlorenchyma Of Opuntia Ficus-Indica (L.) Miller Under Current And Elevated Co2, Park S. Nobel, Muyi Cui, Alvaro A. Israel

United States Department of Energy: Publications

Mature cladodes of Opuntia ficus-indica (L.) Miller have a thick chlorenchyma (about 4 mm) with a relatively high chlorophyll content (0-65 g m^-2), suggesting that light may be greatly attenuated and hence CO₂ fixation negligible in the inner part of this tissue. Indeed, blue light (400-470 nm) and red light (670-685 nm) were 99% attenuated in the outer 2 mm of the chlorenchyma when the cladodes developed under both current and elevated CO₂ concentrations. Nevertheless, the nocturnal acidity increase and ¹⁴C accumulation following a brief exposure to ¹⁴CO₂ at night decreased only 22 …

Archeological Overview And Assessment, Niobrara/Missouri National Scenic Riverways, Nebraska And South Dakota, Anne M. Wolley Vawser, Alan J. Osborn

United States Army Corps of Engineers, Omaha District

This report provides an overview of the archeological resources (prehistoric and
historic) of the various designated units and study areas associated with the Niobrara/Missouri National Scenic Riverways (NIMI) (Figure 1). The purpose of the overview is to pull together information pertinent to archeological resources that has been disseminated in the reports of the numerous projects that have taken place in the study area over the last century. This compilation of the data is necessary to address the current and future management and research needs of the riverway.

A large number of archeological field projects have been conducted in the study …

Field Measurements Of Natural And Artificial Targets Using A Mid-Infrared Laser Reflectance Sensor, Ram M. Narayanan, Steven E. Green

Department of Electrical and Computer Engineering: Faculty Publications

tunable mid-infrared CO₂ laser reflectance sensor operating in the 9-11 pm wavelength range has been developed and field-tested at the University of Nebraska. This system is capable of gathering reflectance data at various wavelengths, incidence angles and linear polarization combinations. Preliminary measurements of various natural and artificial targets such as soil, coniferous and deciduous trees, concrete and brick building material at distances of up to 100 m demonstrate the potential of this system to characterize the mid-infrared reflectance of terrain features for remote sensing applications. Field-acquired data compare well with data on similar materials measured in the laboratory under …

Biological Assessment For Maintenance Of Bank Stabilization Structures Missouri National Recreation River Gavins Point Dam To Ponca State Park, Nebraska

United States Army Corps of Engineers, Omaha District

The location of the proposed maintenance construction project discussed in this document is located between Gavins Point Dam, South Dakota and Ponca, Nebraska, at specific locations as listed in the accompanying plans and specifications.

The proposed construction consists only of maintaining those structures that can reasonably be repaired to alleviate erosion problems for the purpose of maintaining the structural integrity of the existing structures. Any structure that is beyond repair would not be reconstructed, since it would no longer qualify as maintenance. There are nine existing projects within the Missouri National Recreation River (MNRR) segment of the Missouri River. Each …

Oscillating Flow In Channels With Sudden Change In Cross Section, Mounir B. Ibrahim, Waqar Hashim

Mechanical Engineering Faculty Publications

In this paper, we have computationally examined oscillating flow (zero mean between) two parallel plates with a sudden change in cross section. The flow was assumed to be laminar incompressible with the inflow velocity uniform over the channel cross section but varying sinusoidally with time. The cases studied cover wide ranges of Re_max (from 187.5 to 2000), Va (from 1 to 10.66), the expansion ratio (1:2 and 1:4) and A_r (2 and 4). Also, three different geometric cases were discussed: (a) asymmetric expansion/contraction; (b) symmetric expansion/contraction; and (c) symmetric blunt body. For these oscillating flow conditions, the fluid …

Preventing Pesticide Contamination Of Groundwater While Maximizing Irrigated Crop Yield, Richard C. Peralta, M. A. Hegazy, G. Musharrafieh

Civil and Environmental Engineering Faculty Publications

A simulation/optimization model is developed for maximizing irrigated crop yield while avoiding unacceptable pesticide leaching. The optimization model is designed to help managers prevent non-point source contamination of shallow groundwater aquifers. It computes optimal irrigation amounts for given soil, crop, chemical, and weather data and irrigation frequencies. It directly computes the minimum irrigated crop yield reduction needed to prevent groundwater contamination. Constraint equations used in the model maintain a layered soil moisture volume balance; describe percolation, downward unsaturated zone solute transport and pesticide degradation; and limit the amount of pesticide reaching groundwater. Constraints are linear, piecewise linear, nonlinear, and exponential. …

Selecting Controls For Water Distribution Systems, J. Paul Tullis

Reports

One of the key requirements for reliable operations of a water supply system is a thorough analysis and proper selection of the control valves and pumps. For valves, selection criteria includes capacity, pressure loss, controllability, torque, cavitation and transients. Pump selection requires matching the pump performance to varying system demands. Examples are given for single pump operation and use of pumps in series and parallel. When future demands exceed the original design conditions, or if significant changes are required in the operation of the system, each important control device should be analyzed to see if it can operate safely at …

The Source Hydrology Of Severe Sustained Drought In Th Southwestern U.S., David G. Tarboton

Reports

This paper considers the risk of drought and develops drough scenarios for use in the study of severe sustained drought in the Southwestern United States. The focus is on the Colorado River gbasin and regions to which Colorado River water is exported, especially southern California, which depends on water from the Colorado River as well as the four major rivers in northern California. Drought scenarios are developed using estimates of unimpaired historic streamflow as well as reconstructions of streamflow based on tree ring widths. Drought scenarios in the Colorado River are defined on the basis of annual flow at Lees …

A Spatially Distributed Energy Balance Snowmelt Model, David G. Tarboton, Tanveer G. Chowdhury, Thomas H. Jackson

Reports

This paper describes an energy balance snowmelt model developed for the prediction of rapid snowmelt rates responsible for soil erosion and water input to a distributed water balance model. The model uses a lumped representation of the snowpack with two state variables, namely, water equivalent and energy content relative to a reference state of water in the ice phase at 0 degrees Celcius. This energy content is used to determine snowpack average temperature of liquid fraction. This representation of the snowpack is used to determine snowpack average temperature of liquid fraction. This representation of the snowpack is used in a …

Measurements And Modeling Of Snow Energy Balance And Sublimation From Snow, David G. Tarboton

Reports

Snow melt runoff is an important factor in runoff generation for most Utah rivers and a large contributer to Utah's water supply and periodically flooding. The melting of snow is driven by fluxes of energy into the snow during warm periods. These consist of radiant energy from the sun and atmosphere, sensible and latent heat transfers due to turbulent energy exchanges at the snow surface and a relatively small ground flux from below. The turbulent energy exchanges are also responsible for sublimation from the snow surface, particularly in arid environments, and result in a loss of snow water equivalent available …

The Study Of Resistance And Stability Of Vegetation In Flood Channels, William Rahmeyer, David Werth, Rob Cleere

Reports

Preface: The following report was prepared by the Utah Water Research Laboratory of Utah State University in Logan, Utah. The report contains the data and conclusions of flow tests conducted with different types of shrubs and woody vegetation in the hydraulics flumes of Utah State University. The funding agency for this project was the U.S. Army Engineers Waterwasy Experiment Stations, Vicksburg, MS.; Project Name - Flood Control Channels; Work Unit Title - Stability of Vegetative Cover in Flood Control Channels; Work Unit No - 337A3; Federal Contract No - DACW39-94-K-0009. The study was the result of a proposal submitted in …

The Great Salt Lake: A Barometer Of Low Frequency Climate Variability, Upmanu Lall, Michael Mann

Reports

Low frequency (interannual or longer period) climatic variability is of interest bacause of its sugnificance for the understanding and prediction of protracted climatic anomalies. Closed basin lakes are sensitive to long term climatic fluctuations and integrate out high frequency variability. It is thus natural to examine the records of such lakes to better understand long term climate dynamics. Here we use Singular Spectral Analysis (SSA) and Multi-Taper Spectral Analysis (MTM) to analyze the time series of Great Slat Lake (GSL) monthly volume changes from 1848-1992, and monthly precipitation, temperature and streamflow for nearby stations with 74 or more years of …