Engineering Commons^™

Statistical Modeling Of Fatigue Crack Growth, Ignacio Guerra, Tarun Goswami

Biomedical, Industrial & Human Factors Engineering Faculty Publications

The objective of this research is to fit normal and lognormal distributions to fatigue crack growth rate (da/dN) data and present the data in terms of cumulative frequency distribution (f (x)) and a variant of da/dN and mode I stress intensity factor range (ΔΚ), z. The probability density functions (F(da/dN)) were also plotted for the data. The data was compiled from open literature, conducted on a hot section turbine disk material Inconel 718 under a North Atlantic Treaty Organization (NATO) project, through the Advisory Group on Aerospace Research and Development (AGARD). Incomel 718 was tested at 650°C utilizing various specimen …

Life Prediction Of Stainless Steels Used In Nuclear Reactors, Jonathan Clark, Tarun Goswami

Biomedical, Industrial & Human Factors Engineering Faculty Publications

Effects of dwell times and temperature on creep-fatigue behavior of stainless steels have been examined from published data. The temperatures of these materials varied from 430°C to 816°C. Within this temperature range creep and fatigue processes interact and failure occurs in the low-cycle regime. A least square best fit equation was developed from the compiled data fitting all the data points. The variables were temperature, strain rate, dwell time and strain range and were used with and without transformation functions to derive the equation. Statistical analysis was performed showing a very high coefficient of correlation value for the life prediction …

Failure Modes Of Biomedical Implants, Andrew Gratton, Bert Buford, Tarun Goswami, Dana Gaddykurten, Larry Suva

Biomedical, Industrial & Human Factors Engineering Faculty Publications

The metallic biomaterials are very well known among various biomaterials. Stainless steel was used successfully as an implant material in the surgical field, then Vitallium, cobalt based alloys were used as implant materials. Titanium is the newest metallic biomaterial among three main metallic biomaterials, stainless steels, Co-based alloys and titanium alloys. These materials are used for the instrumentation replacing failed hard tissue, for example, artificial hip joints, artificial knee joints, bone plates, dental implants and in similar applications. Biocompatibility characteristics of titanium alloys make it the preferred choice for such applications, additional factors being light weight, excellent mechanical properties, corrosion …

Adaptive Critic-Based Neural Network Controller For Uncertain Nonlinear Systems With Unknown Deadzones, Pingan He, Jagannathan Sarangapani, S. N. Balakrishnan

Electrical and Computer Engineering Faculty Research & Creative Works

A multilayer neural network (NN) controller in discrete-time is designed to deliver a desired tracking performance for a class of nonlinear systems with input deadzones. This multilayer NN controller has an adaptive critic NN architecture with two NNs for compensating the deadzone nonlinearity and a third NN for approximating the dynamics of the nonlinear system. A reinforcement learning scheme in discrete-time is proposed for the adaptive critic NN deadzone compensator, where the learning is performed based on a certain performance measure, which is supplied from a critic. The adaptive generating NN rejects the errors induced by the deadzone whereas a …

The Effect Of Initial Selections In Estimating The Missing Comparisons In An Incomplete Ahp Matrix, Sugeng Setiawan

LSU Master's Theses

One of the most widely used methods in decision-making is the Analytic Hierarchy Process (AHP). With its technique of comparing the alternatives by means of a sequence of pairwise comparison matrices, the AHP is both easy to understand and very versatile. This research aims at contributing some insights on this method, in particular, regarding to what is known as the incomplete AHP. The core of this research is to investigate whether the initial comparisons used to extract the data for a multi-criteria decision making problem, will play a role in producing a relatively accurate estimation of the ranking of the …

Continuity In Dynamic Coalition Operations, Holly A. H. Handley, Larry K. Wentz, Alexander H. Levis

Engineering Management & Systems Engineering Faculty Publications

The combination of participating organizations in a coalition operation often changes over time; the coalition is dynamic and evolves over the course of its mission. A given organization may participate in the coalition only at the stage where its expertise or resources are most needed, while other organizations may participate through the entire course of the operation. As these are independent organizations coming together for a limited time to meet a specific goal, the structure of the coalition must be able to accommodate the different command arrangements, procedures, and other characteristics of each organization. In order to develop a theory …

Assessment Of Slip Severity Among Different Age Groups, Thurmon E. Lockhart, Jeffrey C. Woldstad, James L. Smith

Department of Industrial and Management Systems Engineering: Faculty Publications

A laboratory study utilizing new techniques for assessing slip severity was conducted to investigate the process of inadvertent slips and falls among different age groups. Forty-two subjects from three age groups (young adults, middle-aged, and the elderly) walked on a rectangular track at a self-determined pace. Without the subjects’ awareness, a slippery floor surface was placed on the track over a force-measuring platform. The results indicated that elderly adults’ friction demand (RCOF) was not significantly different from the young and middle-aged adults. The older adults, however, fell more often than the other age groups. Fall recovery threshold (FRT) measures indicated …

A Simulation Based Experiment For Comparing Amhs Performance In A Semiconductor Fabrication Facility, Gerald Mackulak, Paul Savory

Department of Industrial and Management Systems Engineering: Faculty Publications

As the cost and complexity of constructing a semiconductor fabrication facility increases, responsive tools are needed for designing and planning its operations. Discrete-event simulation paired with design of experiments is an effective combination. This article demonstrates how simulation in combination with design of experiments is used to compare the intrabay layout of two automated material handling systems. The difference in stocker robot utilization, number of vehicle moves per hour, and average delivery time for the two intrabay layouts will be compared using a fractional factorial experimental design. The study demonstrates that the distributed storage option is preferable for maximizing manufacturing …

A Comparative Study Of Just-In-Time (Jit) And Theory Of Constraints (Toc) Systems With Varying Constraint Locations And Operational Characteristics, Pirun Hemmondharop

Doctoral Dissertations

"Various researchers have extolled the benefits of Theory of Constraints (TOC), Just-in-Time (JIT), and other manufacturing strategies. Some supporters of JIT argue it is the least costly, while others point to the overall benefits of TOC. There are conflicting claims as to the best manufacturing philosophies which is compounded by the fact that no one system is best in every situation. The success of a production system truly depends on the manufacturing environment rather than the philosophy being used. This study uses computer simulations of differing manufacturing environments to compare Just-in-Time (JIT) and Theory of Constraints (TOC) philosophies over two …

Physical-Statistical Modeling And Optimization Of Cardiovascular Systems, Dongping Du

USF Tampa Graduate Theses and Dissertations

Heart disease remains the No.1 leading cause of death in U.S. and in the world. To improve cardiac care services, there is an urgent need of developing early diagnosis of heart diseases and optimal intervention strategies. As such, it calls upon a better understanding of the pathology of heart diseases.

Computer simulation and modeling have been widely applied to overcome many practical and ethical limitations in in-vivo, ex-vivo, and whole-animal experiments. Computer experiments provide physiologists and cardiologists an indispensable tool to characterize, model and analyze cardiac function both in healthy and in diseased heart. Most importantly, simulation modeling empowers the …

An Analytical Hierarchy Process (Ahp) Assessment Of The Iso 14001-Based Environmental Management System In The Oil And Gas Industry In Malaysia, Vijayalakshmi Benjamin Samuel

Student Works (2000-2009)

Today's business world is changing due to the ever-increasing consciousness for environmental protection and sustainable development. Customers are taking into account environmental considerations in their supplier selection, and are increasingly buying products with identifiable environmental attributes. In this study, the critical decision criteria, sub-criteria and benefits of the adoption and implementation of the ISO 14001-based environmental management system (EMS) in the Malaysian oil and gas sector were studied using the analytical hierarchy process (AHP) approach. An empirical study was performed to investigate the relative weights and priorities of these criteria and benefits. An AHP decision model of EMS adoption was …

Application Of Artificial Neural Networks To Sensitivity Analysis And Modeling Of Small Office Buildings, Quan Tang

Dissertations and Theses @ UNI

Sensitivity analysis and Multiple Linear Regression (MLR) are the most extensively used techniques in studying the input-output relationship in building thermal systems. However, both MLR and most methods for sensitivity analysis do not account for nonlinear components embedded in building energy systems. Thus, their results might be distorted.

In this study, the Artificial Neural Networks (ANN) technique was applied to sensitivity analysis and modeling of an imaginary small office in order to (a) examine how the annual energy consumption responded to 40 building design parameters and evaluate relative contributions of these parameters to the variation of the building energy performance, …

Visco-Elastic Creep In The Lumbar Spine Associated With Static Flexion: A Feline Model, Guntulu Selen Hatipkarasulu

LSU Master's Theses

Musculoskeletal disorders (MSDs) have become a major health concern with the industrial revolution and technological advances. The National Institute for Occupational Safety and Health (NIOSH) recently estimated the cost of MSDs at $13 to $20 billion annually. Back, spine, and spinal cord disorders add up to 60% of the total MSD injuries. Based on pervious studies, it is known that lumbar ligaments play a limited or little role in stabilizing the spine; where as the musculature around the spine is the major stabilizing structure. However, repetitive or prolonged static displacement or load induces creep in passive tissues of the spine …

The Shipboard Office' : The Role Of It And Multi-Media Systems In Managing Engineering Operations And Maintenance Onboard Ship, Okechukwu Ebere Sylvanus Obara

World Maritime University Dissertations

This dissertation is an investigation of the roles of information technology and multimedia systems in the management of engineering operations and maintenance onboard ships. It considers the implications and constraints of adopting these technology tools on the economies of ship owners or managements companies, Maritime Administrations, and the Maritime Education and Training Institutions, especially in the developing countries. The study reviews the various shipboard maintenance policies and management techniques currently being practised in the traditional shipboard office with a view of understanding its constraints and the needs of adopting the various technological tools and systems. It also examines critically, the …

Acuta Enews December 2001, Vol.30, No. 12

ACUTA Newsletters

In This Issue

Michigan Tech Chooses Network Appliances

ACUTA Events

The "New Member Roundup"- Why It's Important

DC Update

ACUTA EVENTS

Mexico Dialing Pattern Change

Did the Lights Go Out? Events, Results, and Impacts

Board Report

Thanks to Our Sponsors!

Fourth Quarter 2001 Web Sites to See

Welcome New Members

Positions Available

Modeling And Analysis Of Social Networks, Robert S. Renfro Ii

Theses and Dissertations

This dissertation develops new methods for the modeling and analysis of social networks. Social networks describe the complex relationships of individuals and groups in multiple overlapping contexts. Influence in a social network impacts behavior and decision making in every setting in which individuals participate. This study defines a methodology for modeling and analyzing this complex behavior using a Flow-Model representation. Multiple objectives in an influencing effort targeted at a social network are modeled using Goal Programming. Value Focused Thinking is applied to model influence and predict decisions based on the reaction of the psychological state of individuals to environmental stimuli. …

Development Of A Systems Engineering Model Of The Chemical Separations Process: Quarterly Progress Report 8/16/01- 11/15/01, Yitung Chen, Randy Clarksean, Darrell Pepper

Separations Campaign (TRP)

The AAA program is developing technology for the transmutation of nuclear waste to address many of the long-term disposal issues. An integral part of this program is the proposed chemical separations scheme.

Two activities are proposed in this Phase I task: the development of a systems engineering model and the refinement of the Argonne code AMUSE (Argonne Model for Universal Solvent Extraction). The detailed systems engineering model is the start of an integrated approach to the analysis of the materials separations associated with the AAA Program. A second portion of the project is to streamline and improve an integral part …

Acuta Enews November 2001, Vol.30, No. 11

ACUTA Newsletters

In This Issue

Tornado Strikes Maryland Campus

Thanks to Exhibitors for 2001

ACUTA Events

DC Update

IT Disasters Recovery Near the World Trade Center

Board Report

Business Continuity Planning in Higher Ed

Welcome New Members

Positions Available

Pickup And Delivery Problem With Time Windows: Algorithms And Test Case Generation, Hoong Chuin Lau, Zhe Liang

Research Collection School Of Computing and Information Systems

In the pickup and delivery problem with time windows (PDPTW), vehicles have to transport loads from origins to destinations respecting capacity and time constraints. In this paper, we present a two-phase method to solve the PDPTW. In the first phase, we apply a novel construction heuristics to generate an initial solution. In the second phase, a tabu search method is proposed to improve the solution. Another contribution of this paper is a strategy to generate good problem instances and benchmarking solutions for PDPTW, based on Solomon's benchmark test cases for VRPTW. Experimental results show that our approach yields very good …

Acuta Enews October 2001, Vol.30, No. 10

ACUTA Newsletters

In This Issue

How Telecom Answered the Call

ACUTA EVENTS

New Member Roundup

DC Update

Board Report

Welcome New Members

Positions Available

The Effect Of Cockpit Noise On Aircraft Pilot Psychomotor Performance, Kelechi (Kc) Nwabeke

Master's Theses - Daytona Beach

The purpose of this study was to evaluate the effect of cockpit noise on aircraft pilot psychomotor performance on a simulated tracking task. The performance of thirty-two participants was measured on a vertical and horizontal tracking task. In the control group, eight participants were used in a quiet condition. In the experimental group, eight participants were exposed to low intensity cockpit noise (50 dBA), eight participants were exposed to medium intensity cockpit noise (60 dBA) and eight participants were expose to high intensity cockpit noise (70 dBA). The performance of the control and experimental groups was measured in an advanced …

Freightliner Llc Manufacturing Optimization, Jerry Compton, Ryan Jefferis, Hasnah Mat-Amin, Felix Ngoussou

Engineering and Technology Management Student Projects

Freightliner LLC has been producing innovative products since 1942 for the trucking industry. Following a 1981 acquisition by Daimler-Benz AG, Freightliner has steadily gained market share through acquisition and fleet sales. Following record production in 1999 at maximum yield levels, year 2000 hit the heavy truck market especially hard. High diesel fuel prices, low used truck values, and a slowing economy were just a few reasons for reduced truck sales.

Through Ql of 2001, heavy vehicle production was down 54% compared to 2000 in attempts of lowering inventory amounts. In this new market, capacity is no longer the overall manufacturing …

Determination Of The Impact Of A Human Capital Decision Cost Model On The Economic Performance Measures Of A Technical Services Company, Jeffery A. Temple

Engineering Management & Systems Engineering Theses & Dissertations

Human Capital has a major impact on cash flow management decisions in a Technical Services company. Decisions to hire or terminate employees to meet contract requirements affect the company's economic value. The objective of this research is to develop a model that assists management in establishing a starting point in making, as efficiently as possible, those decisions that impact employees' lives. To understand that impact, the operations and economic parameters of a Technical Services company are compared with those of a manufacturing company. This analysis establishes two · essential points for Technical Services organizations; first, that the capital investment decision …

High Temperature Fatigue Crack Growth Behavior Of Ti-6al-4v, N. K. Arakere, Tarun Goswami, J. Krohn, N. Ramachandran

Biomedical, Industrial & Human Factors Engineering Faculty Publications

Experimental evaluation of high temperature, Fatigue Crack Growth Rate (FCGR) data for Ti-6A1-4V, a titanium alloy, is presented. The FCGR data were measured at room temperature, 175, 230, 290 and 345°C using the Direct Current Potential Difference (DCPD) technique. Compact Tension (CT) specimens were used in the program and crack growth rates (da/dN) vs. Mode I stress intensity factor ranges (ΔΚ) were plotted as a function of temperature. A temperature rise from 175 to 345°C did not cause a substantial increase in crack growth rates within the Stage II region where a linear relationship describes the behavior. Fonnation of secondary …

Acuta Enews September 2001, Vol.30, No. 9

ACUTA Newsletters

In This Issue

Conference Highlights

ACUTA EVENTS

DC Updates

Board Report

ACUTA Plans Audio Seminar on Taxes, Surcharges, and Fees

Welcome New Members

Positions Available

A Decomposition Approach For The Multi-Modal, Resource-Constrained, Multi-Project Scheduling Problem With Generalized Precedence And Expediting Resources, Michael L. Fredley

Theses and Dissertations

The field of project scheduling has received a great deal of study for many years with a steady evolution of problem complexity and solution methodologies. As solution methodologies and technologies improve, increasingly complex, real-world problems are addressed, presenting researchers a continuing challenge to find ever more effective means for approaching project scheduling. This dissertation introduces a project scheduling problem which is applicable across a broad spectrum of real-world situations. The problem is based on the well-known Resource-Constrained Project Scheduling Problem, extended to include multiple modes, generalized precedence, and expediting resources. The problem is further extended to include multiple projects which …

Theater-Level Stochastic Air-To-Air Engagement Modeling Via Event Occurrence Networks Using Piecewise Polynomial Approximation, David R. Denhard

Theses and Dissertations

This dissertation investigates a stochastic network formulation termed an event occurrence network (EON). EONs are graphical representations of the superposition of several terminating counting processes. An EON arc represents the occurrence of an event from a group of (sequential) events before the occurrence of events from other event groupings. Events between groups occur independently, but events within a group occur sequentially. A set of arcs leaving a node is a set of competing events, which are probabilistically resolved by order relations. An important EON metric is the probability of being at a particular node or set of nodes at time …

Development Of A Systems Engineering Model Of The Chemical Separations Process, Yitung Chen, Darrell Pepper, Randy Clarksean

Separations Campaign (TRP)

Two activities are proposed: the development of a Systems Engineering model and the refinement of the Argonne code AMUSE (Argonne Model for Universal Solvent Extraction). The detailed systems engineering model will be the start of an integrated approach to the analysis of the materials separations associated with the national AAA program. A second portion of the project will streamline and improve an integral part of the overall systems model, which is the software package AMUSE. AMUSE analyzes the UREX process and other related solvent extraction processes and defines many of the process streams that are integral to the systems engineering …

Acuta Enews August 2001, Vol.30, No. 8

ACUTA Newsletters

In This Issue

Safety First at Section Hall

ACUTA Events

DC Update

Overheard on the Listserve: RF Interference on Campus

Welcome New Members

Positions Available

A Comparative Study On Projected And Actual Manufacturing Times To Identify The Source Of Customer Delinquency, Zaki Kuruppalil

All-Inclusive List of Electronic Theses and Dissertations

This study was an investigation of the projected lead time and the actual lead time for a part manufactured at Tri-Industries Inc., Terre Haute, Indiana. The research was focused on a single part produced in Tri-Industries. The problem was that there is a difference in the projected lead time and the actual lead time of the part under investigation. The actual lead time was longer than projected lead time, which resulted in the company being delinquent in customer delivery. This investigation was conducted to find out the source for customer delinquency for a single part in Tri-Industries. The conclusion was …