Operations Research, Systems Engineering and Industrial Engineering Commons^™

Applicability Of Modified Diercks Equation With Nrim Data, Tarun Goswami

Biomedical, Industrial & Human Factors Engineering Faculty Publications

The applicability of the modified Diercks equation (MDE) was assessed with elevated temperature low cycle fatigue (ETLCF) data generated by the National Research Institute for Metals (NRIM) for lCr-Mo-V, 1.25Cr-Mo, 2.25Cr-Mo and 9Cr-lMo steels respectively. The modified Diercks equation was assessed with data generated with symmetrical, slow-fast and hold-time waveforms for low alloy steels. The following characteristics were observed: Symmetrical waveforms: Five strain rates were used with these waveforms where predicted life was by a factor of ± x2 for 77%, 87%, 82% and 92% of data points for lCr-Mo-V, 1.25Cr-Mo, 2.25Cr-Mo and 9CrlMo steels respectively. Slow-fast waveforms: Diercks equation …

Issues In Developing An Undergraduate Simulation Course, Paul Savory

Department of Industrial and Management Systems Engineering: Faculty Publications

Experience in developing an undergraduate simulation course is described. The course introduces the philosophies, principles, and methodologies for discrete-event simulation modeling. Strategy in choosing the course simulation software is discussed, plus important areas of teaching emphasis are highlighted.

Simulation Project Characteristics In Industrial Settings, Paul Savory

Department of Industrial and Management Systems Engineering: Faculty Publications

In a survey of practitioners of discrete-event simulation from industry and research institutes who "build models for money," we asked about project goals, user backgrounds and training, organizational types and activities, software and hardware choices, modeling team composition, and effort allocation within a modeling project. We found that (1) only about half of the practitioners have three or more years experience, (2) many academics feel strongly affiliated with their industry clients rather than with their university employers, (3) shop-floor supervisors rarely lead simulation projects, even though their knowledge of the system may be unparalleled, (4)simulation models are generally described as …

Acuta Enews January 1995, Vol. 24, No. 1

ACUTA Newsletters

In This Issue

Board Report

President's message

Telecom Resources Library Update

Developing a campus telecom plan

Precautions combat

phone fraud

DC at a glance

Using Matlab To Illustrate The 'Phenomenon Of Aliasing', Sol Neeman, Ph.D.

Engineering Studies Faculty Publications and Creative Works

The phenomenon of aliasing is important when sampling analog signals. In cases where the signal is bandlimited, one can avoid aliasing by ensuring that the sampling rate is higher than the Nyquist rate . But in cases where the signal is not bandlimited , aliasing is unavoidable if the signal is not filtered before it is sampled. It is then crucial to understand the phenomenon in order to estimate the distortion generated when the signal is reconstructed from its samples. Using the software package MATLAB by MathWorks, Inc ., two examples are presented. The first is a pure sinusoid which …

A Staggered-Diamond Design For Automated/Manual-Hov Highway-To-Highway Interchanges And Constraints On Ahs Design For Accommodating Automated Highway Change, Jacob Tsao

Faculty Publications

This paper consists of two components. The First component addresses a key AHS infrastructure support issue—providing eight extra connector ramps, in addition to the eight existing highway-to-highway connector ramps for the conventional manual traffic, at a highway-to-highway interchange for accommodating continuous automated driving from one highway to the crossing highway. The proposed staggered-diamond design requires only four, instead of eight, separate structures and hence greatly increases the feasibility of AHS infrastructure support. However, the reduced infrastructure complexity at such interchanges could still constrain considerably the design, operation and evolution of AHS. This is the focus of the second component. The …

Stage Definition For Ahs Deployment And An Ahs Evolutionary Scenario, Jacob Tsao

Faculty Publications

Pros and cons of various mature Automated Highway Systems (AHS) have been a subject of intense study. However, such discussions are nothing but intellectual exercises unless the issue of how to evolve, in a planned and managed fashion, the current highway systems towards these mature AHS is also addressed. Since full functionality of a mature AHS cannot be realized suddenly, discrete functional steps must be identified and optimized. This paper defines an evolutionary stage towards a mature AHS as any discernible functional increment whose realization may encounter considerable difficulties requiring a significant amount of conscious effort to overcome. A good …

Creep Fatigue, Part I: Compilation Of Data And Trends In The Creep-Fatigue Behavior Of Low Alloy Steels, Tarun Goswami

Biomedical, Industrial & Human Factors Engineering Faculty Publications

This paper describes an attempt to compile the creep-fatigue data of low alloy steels. In part I, international data have been collected to compare the variability that exists in a particular low alloy steel when characterized in different laboratories. From this work of compilation, trends in the creep-fatigue behavior of low alloy steels have been identified in Part II of this paper and a review of life prediction methods and assessments will be discussed in subsequent papers. The creep-fatigue behavior, in general, improved with the increase in chromium content; however, when additional alloying elements were added to a standard alloy …

Creep Fatigue, Part Ii: Creep Fatigue Life Prediction: Methods And Trends, Tarun Goswami

Biomedical, Industrial & Human Factors Engineering Faculty Publications

Creep-fatigue data of low allow steels were compiled from international sources, and trends in creep-fatigue behavior were identified in Paper I. This paper reviews the methods of creep-fatigue life prediction that were assessed from the compiled data. The methods reviewed in this paper are phenomenological in nature. However, an empirical method has also been discussed which offers very high reliability of the prediction capability. Various test requirements, from which material parameters are determined for each method, have been tabulated. No single method has been generalized as a best method of life prediction for all types of creep-fatigue test conditions.

Creep-Fatigue Life Prediction - A Ductility Model, Tarun Goswami

Biomedical, Industrial & Human Factors Engineering Faculty Publications

Creep-fatigue life prediction methods are briefly reviewed. Phenomenological methods of life prediction are very popular, since they use several test and metallographic parameters in model formulation. They also require numerous test parameters determined from specialized tests. Requirements of phenomenological methods have been summarized. Ductility measurement and modeling aspects have been reviewed. A new model has been developed with the assumption that with increasing fatigue cycles the ductility gradually decreases and the specimen fails as a result of exhaustion of ductility. This has been achieved in terms of dynamic viscosity (product of stress and cycle time), equated with material toughness, which …

Linearly-Constrained Entropy Maximization Problem With Quadratic Costs And Its Applications To Transportation Planning Problems, Shu-Cherng Fang, Jacob Tsao

Faculty Publications

Many transportation problems can be formulated as a linearly-constrained convex programming problem whose objective function consists of entropy functions and other cost-related terms. In this paper, we propose an unconstrained convex programming dual approach to solving these problems. In particular, we focus on a class of linearly-constrained entropy maximization problem with quadratic cost, study its Lagrangian dual, and provide a globally convergent algorithm with a quadratic rate of convergence. The theory and algorithm can be readily applied to the trip distribution problem with quadratic cost and many other entropy-based formulations, including the conventional trip distribution problem with linear cost, the …

Retrieval Of Atmospheric Turbidity Coefficiant And Water Column Density Fro Solar Irradiance Data, Felix Tendeku

Journal of the Arkansas Academy of Science

Ground-based measurement of solar irradiance has been made using a spectroradiometer at wavelengths inapx-water absorption band. An algorithm is formulated to retrieve simultaneously the atmospheic water column density and Angstrom's turbidity coefficient. The transmission models used to account for the contribution from diverse atmospheic absorbing and scattering elements are presented.

Variance And Uncertainty Measures Of Population Diversity Dynamics, Mark A. Bedau, Martin Zwick, Alan Bahm

Systems Science Faculty Publications and Presentations

We define variance and uncertainty measures of population diversity. Both measures have precise decompositions that we can exploit in analysis of evolutionary dynamics. We discuss how these measures are related and how they can be observed in artificial and natural evolving systems.

Identification Of Success Factors In The Implementation Of Computer-Integrated Manufacturing, Dean Harold Jensen

Dissertations and Theses @ UNI

The review of recent literature showed a clear trend within the manufacturing sector toward the integration of design and production activities through increased application of the computer. The competitive advantages of computer integration were reported, as well as increased risk due to the amount of time and capital expended in system implementation. The identification of computer integrated manufacturing (CIM) success factors may reduce this risk.

Prior efforts to identify success factors for other areas of endeavor showed that success factors tended to vary with the four project phases, but were stable over time within a particular phase. More recently, empirical …

Perceived Importance Of Iso 9000 Factors As Indicators Of Quality In Industrial Technology Related Programs At Four-Year State Regional Universities, Floyd L. Olson

Dissertations and Theses @ UNI

Industry has often used a quality standard known as ISO 9000. No evidence has been located demonstrating the applicability of an industrial quality model to a singular academic department. The problem of this study was to determine if the guidelines for ISO 9004-2 could have been considered appropriate for Industrial Technology related programs and how they could have been used to indicate quality within such programs.

The purpose of this study was to seek knowledge relating the importance of ISO 9004-2 guidelines to audit and/or improve the quality management of Industrial Technology related departments at 4-year state regional universities. This …

Stage Definition For Ahs Deployment And An Ahs Evolutionary Scenario, Jacob Tsao

H.-S. Jacob Tsao

Pros and cons of various mature Automated Highway Systems (AHS) have been a subject of intense study. However, such discussions are nothing but intellectual exercises unless the issue of how to evolve, in a planned and managed fashion, the current highway systems towards these mature AHS is also addressed. Since full functionality of a mature AHS cannot be realized suddenly, discrete functional steps must be identified and optimized. This paper defines an evolutionary stage towards a mature AHS as any discernible functional increment whose realization may encounter considerable difficulties requiring a significant amount of conscious effort to overcome. A good …

A Staggered-Diamond Design For Automated/Manual-Hov Highway-To-Highway Interchanges And Constraints On Ahs Design For Accommodating Automated Highway Change, Jacob Tsao

H.-S. Jacob Tsao

This paper consists of two components. The First component addresses a key AHS infrastructure support issue—providing eight extra connector ramps, in addition to the eight existing highway-to-highway connector ramps for the conventional manual traffic, at a highway-to-highway interchange for accommodating continuous automated driving from one highway to the crossing highway. The proposed staggered-diamond design requires only four, instead of eight, separate structures and hence greatly increases the feasibility of AHS infrastructure support. However, the reduced infrastructure complexity at such interchanges could still constrain considerably the design, operation and evolution of AHS. This is the focus of the second component. The …

Linearly-Constrained Entropy Maximization Problem With Quadratic Costs And Its Applications To Transportation Planning Problems, Shu-Cherng Fang, Jacob Tsao

H.-S. Jacob Tsao

Many transportation problems can be formulated as a linearly-constrained convex programming problem whose objective function consists of entropy functions and other cost-related terms. In this paper, we propose an unconstrained convex programming dual approach to solving these problems. In particular, we focus on a class of linearly-constrained entropy maximization problem with quadratic cost, study its Lagrangian dual, and provide a globally convergent algorithm with a quadratic rate of convergence. The theory and algorithm can be readily applied to the trip distribution problem with quadratic cost and many other entropy-based formulations, including the conventional trip distribution problem with linear cost, the …

Investigation Of The Relationship Between Fuel Injection Nozzle Roto Flow And Hydra Flow And The Engine Torque Of A Diesel Engine, Guang Jin

Dissertations and Theses @ UNI

The purpose of this study was to investigate the possibility of reducing diesel engine torque variation by optimizing fuel injection nozzle tip configuration. In order to reduce engine torque variation, test runs were conducted to determine whether fuel injection nozzles affected diesel engine torque. There was a further effort to determine whether a correlation existed between the fuel injection nozzle roto flow and hydra flow, and the engine torque at specified engine speeds.

Engines installed in cotton pickers and tractors were used for this study. Engines, five from the cotton picker and five from the tractor group were chosen randomly …

Comparing Traditional Statistical Models With Neural Network Models: The Case Of The Relation Of Human Performance Factors To The Outcomes Of Military Combat, William Oliver Hedgepeth

Engineering Management & Systems Engineering Theses & Dissertations

Statistics and neural networks are analytical methods used to learn about observed experience. Both the statistician and neural network researcher develop and analyze data sets, draw relevant conclusions, and validate the conclusions. They also share in the challenge of creating accurate predictions of future events with noisy data.

Both analytical methods are investigated. This is accomplished by examining the veridicality of both with real system data. The real system used in this project is a database of 400 years of historical military combat. The relationships among the variables represented in this database are recognized as being hypercomplex and nonlinear.

The …

A Nonlinear Dynamic Method For Supporting Large-Scale Decision-Making In Uncertain Environments, Wayne Woodhams

Engineering Management & Systems Engineering Theses & Dissertations

This research developed a methodology for supporting decision making by reducing uncertainty in decision environments which are too large, dynamic and complex to be treated by traditional quantitative and simulation techniques. These environments are complex because of the free choice associated with human involvement, and the existence of a large number of interrelated factors which influence the outcomes of the decision process. They are dynamic because the ground rules affecting those interrelationships are constantly changing. Uncertainty cannot be treated probabilistically, since identification of a full set of outcomes and factors of influence is not possible.

The venue for the investigation …