Engineering Commons^™

Two-Stage Stochastic Linear Programming With Recourse: A Characterization Of Local Regions Using Response Surface Methodology, David T. Mills

Theses and Dissertations

The LP recourse problem applies to two-stage optimization problems where uncertainty in resource availability of the second stage hinders informed decision making. The recourse function affords a way to compensate "later" for an error in prediction "now." The literature provides a rich body of work on the optimization of such problems, but little research has been accomplished regarding the characterization of the surface in the local region of optimality, in particular sensitivity analysis. A decision maker faced with considerations other than the modeled objective function must be presented with a way to estimate the impact of operating at non-optimal decision …

Solving The Multidimensional Multiple Knapsack Problem With Packing Constraints Using Tabu Search, Jonathan M. Romaine

Theses and Dissertations

This paper presents a methodology for solving military aircraft load-scheduling problems modeled as a multidimensional multiple knapsack problem, Because of the computational time associated with applying conventional algorithms to this type of problem, we employ tabu search to determine how much cargo a heterogeneous group of aircraft can carry. This study extends the previous work of Chocolaad in two areas. First, we modify Chocolaad's algorithms to solve the multiple (rather than the single) knapsack problem under the constraints he defined for the Airlift Loading Problem. Second, we drop his assumption of a homogeneous group of aircraft. We validate our model …

A Value Focused Approach To Determining The Top Ten Hazards In Army Aviation, Brian K. Sperling

Theses and Dissertations

The United States Army Safety Center is challenged with identifying the top ten most severe hazards in Army Aviation. This research utilizes value-focused thinking and multiattribute preference theory concepts to produce a decision analysis model designed to aid decision-makers in their analysis process. The severity model is based on the Army's Risk Management doctrinal manual and has been tailored specifically for aviation related accidents and hazards. The model determines the severity and risk ranking for 65 categories of accidents and 24 existing hazards. A sensitivity analysis is conducted to examine the effects of variations in the weights of the top-level …

Technology Selection For The Air Force Research Laboratory Air Vehicles Directorate: An Analysis Using Value Focused Thinking, Michael F. Winthrop

Theses and Dissertations

A technology selection model was developed for the Air Vehicles Directorate of Air Force Research Laboratory. The model was developed and demonstrated to aid in addressing the question of what technologies Air Vehicles' should invest in to remain consistent with Air Force values. Both Value-Focused Thinking and optimization approaches were used to identify the value of Air Vehicles technology, to provide insights to Air Vehicles' decision-makers, to determine where value gaps might exist with the scored alternatives, and to determine how sensitive the model was to changes. As a demonstration of the approach, seven technologies were scored, representing all three …

Multi-Discipline Network Vulnerability Assessment, Karilynne Wallace

Theses and Dissertations

Air Force Space Command has a mission to provide real-time, survivable, and enduring communications, surveillance, environmental monitoring, navigation, and warning....according to Air Force Space Handbook - A War Fighters Guide to Space. In order to prevent disruption of the critical networks in Space Command, a vulnerability assessment must be performed. The set of components called a vulnerability set, which could cause network disruption, must be identified and prioritized. In order to move beyond subjective prioritization, implementation of a quantitative methodology that measures the value of each vulnerability set is needed. This thesis proposes a technique for vulnerability assessment of a …

Visualizing Early-Stage Breast Cancer Tumors In A Mammographic Environment Through A 3-Dimensional Mathematical Model, Christopher B. Bassham

Theses and Dissertations

In response to the insidious and deadly nature of breast cancer and the less-than-perfect detection ability of mammography, we develop a mathematical model as a foundation to the long-term goal of improving early breast cancer detection. By using modeling and simulation to construct an accurate breast cancer tumor model, we hope to solve the problems associated with mammogram misdiagnosis and, perhaps as a by-product, lend insight to tumor development dynamics. The final tumor model, written in MATLAB, provides realistic tumor growth and 2-dimensional visualization of 3-dimensional structures. Earlier modeling attempts capture slices of the tumor in the 2-dimensional growth spaces. …

The Quota Allocation Model: The Linear Optimization Of A Markov Decision Process, David A. Brown

Theses and Dissertations

One of the many needs of the Air Force is advanced technical degrees. These degrees can be acquired in three ways: the Air Force can directly recruit personnel with the required degrees; Air Force personnel can obtain them during off duty time from local civilian colleges near their base; or the Air Force can provide advanced academic degrees (AADs) through the Air Force Institute of Technology (AFIT) or AFIT-sponsored programs. In 1995, the AFIT Commandant initiated a re-engineering study to review the AFIT mission. One of the initiatives of that study was the Quota Allocation Model (QuAM). The QuAM model …

A Bayesian Decision Model For Battle Damage Assessment, Daniel W. Franzen

Theses and Dissertations

Battle damage assessment (BDA) is critical to success in any air campaign. However, Desert Storm highlighted numerous deficiencies in the BDA process, and operations since Desert Storm continue to point out weaknesses. We present a review of the Phase I BDA decision, or physical damage assessment, and model the decision process using a Bayesian belief network. Through subject matter expert (i.e., the targeteers) elicitation sessions, imagery was found to be critically important to the BDA process yet this information is generally not retained. This use of "perfect information" is delineated in the BDA process models. We proposed a methodology based …

Implementation Of The Metaheuristic Tabu Search In Route Selection For Mobility Analysis Support System, David M. Ryer

Theses and Dissertations

This thesis employs a reactive tabu search heuristic implemented in the Java programming language to solve a real world variation of the vehicle routing problem with the objective of providing quality routes to Mobility Analysis Support System (MASS). MASS is a stochastic simulation model used extensively by Air Mobility Command (AMC) to analyze strategic airlift capabilities and future procurement decisions. This dynamic real world problem of strategic and tactical airlift possesses a number of side constraints such as vehicle capacities, route length and time windows in a sizeable network with multiple depots and a large fleet of heterogeneous vehicles. Finding …

An Evaluation And Comparison Of The Ace And Brace Airfield Models, David W. Wiliams

Theses and Dissertations

Airfields are a critical aspect of our military's ability to project power or respond to crises throughout the world. It is crucial that mobility planners have an effective means to estimate the capacity of these airfields. The objective of this research is to examine common mobility metrics and evaluate existing means of measuring them. Currently, Air Mobility Command has two models, the Airfield Capacity Estimator (ACE) and the Base Resource and Capabilities Estimator (BRACE), that were designed to estimate the resource requirements and capacities of an airfield. This study offers a critical evaluation and comparison of the two models. Discrepancies …

An Approach For Tasking Allocated Combat Resources To Targets, David A. Koewler

Theses and Dissertations

Tasking allocated combat aircraft to strike targets is a complicated and time-consuming process for combat planners. Currently, the process of scheduling missions is a two to four day process. To be able to respond quickly to the changing conditions of the battlefield, the military needs to compress the time that this process requires. Despite efforts to develop computer-based tools to automatically plan missions, combat planners still manually perform most of the tasking and scheduling of aircraft and targets. Unfortunately some of the tools currently available are perceived to be complicated and time consuming to use by the planners. They also …

Selection Of Psychophysiological Features Across Subjects For Classifying Workload Using Artificial Neural Networks, Trevor I. Laine

Theses and Dissertations

The issue of pilot workload is important to the United States Air Force because pilot overload or task saturation leads to decreases in mission effectiveness. Additionally, in the most extreme cases, pilot overload may lead to the loss of aircraft and crewmember lives. Current research efforts are utilizing psychophysiological data including electroencephalography (EEG), cardiac, eye-blink, and respiration measures in an attempt to identify workload levels. The primary focus of this effort is to determine if a single parsimonious set of psychophysiological features exists for accurately classifying workload levels between multiple test subjects. To accomplish this objective, the signal-to-noise (SNR) saliency …

A Decision-Oriented Framework For Evaluating Deployment Strategies For Intelligent Transportation Systems, H.-S. Jacob Tsao

Faculty Publications

Because Intelligent Transportation Systems (ITS) R&D is performed for the ultimate deployment in the real world, deployment issues may limit design options for ITS concepts and technologies and, hence, can be viewed as constraints on ITS R&D. Therefore, ITS deployment issues must be studied at the outset of the R&D process. This paper develops a framework to help recognize and organize such issues. The findings can be used by ITS researchers in developing deployable ITS concepts and technologies and by ITS promoters in deploying ITS technologies having been developed already. Based on a focus on decisions impacting the deployment of …

Acuta Enews February 1999, Vol.28, No. 2

ACUTA Newsletters

In This Issue

Call for Nominations: ACUTA Board of Directors 1999-2000

Levine, McDonalds to Speak at Seminars

Network Challenges for the 21st Century

Overheard on the Listserve

Board Report

Distance Ed Institutes

DC at a Glance

Welcome New Members

Positions Available

A Leader Is a Big Thinker- The Magnet That Attracts Others

Analysis Of A Non-Trivial Queueing Network, Kelly Scott Bellamy

Theses and Dissertations

In studying complex queueing networks, one generally seeks to employ exact analytic solutions to reduce burden on computational resources. Barring the existence of an exact solution, the alternatives include approximation techniques and simulation. Approximation is the more attractive alternative from a time and effort perspective; however, cases exist that are not amiable to this technique. This work increases the flexibility of approximation techniques in obtaining estimates of congestion measures for complex, open queueing networks having several customer classes and class-dependent structures. We accomplish this by providing the procedure to aggregate multiple classes into a single class in order to apply …

Metrics For Estimating The Product Disassembly Effort, Pradeep Kumar Yedlarajaiah

Theses

The concepts of environmentally friendly manufacturing and ecological reuse of materials have resulted in an increase in the number of disposed products that are disassembled. Moreover, the imposition of EPA regulations is forcing companies to invest in methods for protecting the environrnent. The first strategy in this vein is material recycling. The issue of recycling became important because of the limited landfill space, diminishing natural resources, environmental pollution due to dumping of products containing hazardous materials. Likewise, it is projected that the cost of extracting materials from natural resources is going to be much more expensive when compared to reclaiming …

Worn Tool Forces Based On Ploughing Stresses, Daniel Waldorf, Shiv G. Kapoor, Richard E. Devor

Industrial and Manufacturing Engineering

Recent work in modeling of the ploughing mechanism in basic metal machining may provide a means of estimating the additional forces to be expected when cutting with a worn tool. The results predict the rubbing stresses due to the finite radius of an unworn tool edge. Since an unworn tool can be thought of as a worn tool with a wear land width VB = 0, these stresses can make up part of a strategy for predicting the additional forces incurred by a worn tool. This paper develops a wear model by proposing a technique for utilizing the stresses predicted …

Acuta Enews January 1999, Vol.28, No. 1

ACUTA Newsletters

In This Issue

High Priorities for '99

Board Report

Making Choices: ATM vs. Gigabit Ethernet

Overheard on the Listserve: Is VoIP for Me?

DC at a Glance

Positions Available

Welcome New Members

Universal Translations Service

Use Telephone Wires To Create a Household Network

Information, Please

High Speed Networking

ACUTA Member Needs Assessment: Members are Highly Satisfied with ACUTA Services

Facility Layout Of Irregular-Shaped Departments Using A Nested Approach, Alan Mckendall, James Noble, Cerry Klein

Faculty & Staff Scholarship

The facility layout problem is a very difficult and widely studied optimization problem. As a result, many facility layout models and techniques have been developed. However, the literature does not fully consider or control irregular-shaped departments. In this paper, the nested facility layout problem is defined whereby irregular-shaped departments(i.e. L-shaped, O-shaped or U-shaped) can be generated and controlled. This is a unique problem that can be used to efficiently layout workstations, storage areas and other departments within departments, while arranging the departments with respect to an objective. The objective considered here is to minimize material handling cost. We present a …

Spatial And Temporal Factors In Estimating The Potential Of Ride-Sharing For Demand Reduction, H.-S. Jacob Tsao, Da-Jie Lin

Faculty Publications

Traffic congestion has been a pervasive problem in many urban areas of this country. This paper studies the potential of carpooling among unrelated partners (i.e., inter-household carpooling) for demand reduction during peak commute hours. Basic questions about this potential include the following. Can the current population density, origin-destination distribution, tolerable pick-up and drop-off delays, departure time distribution, and the tolerance for deviation from preferred departure time support a sizable carpooling population that can make a significant contribution to traffic demand reduction? Could the proportion of long trips that are likely candidates for carpooling (e.g., those long trips with same O-D) …

Value-Based Product Structure Evaluation For Disassembly, Shivakumar Viswanathan, Venkat Allada

Engineering Management and Systems Engineering Faculty Research & Creative Works

Designing for the ease of end of life (EOL) disassembly is an important design function. The product structure that is the spatial relationships between the parts of the product and the value distribution over them plays an important role in determining the ease and profitability of disassembly. This paper presents a conceptual methodology to determine the effect of the spatial precedence on the desired value precedence of the product. The methodology introduces a digraph called the bureau graph to model this relationship between the spatial and value precedence structures. Based on this modeling indices are derived that provide a holistic …

Models In Manual Materials Handling, M. M. Ayoub, Jeffrey C. Woldstad

Department of Industrial and Management Systems Engineering: Faculty Publications

The ergonomics approach to manual materials handling (MMH) tasks defines a Man-Task-Environment System. A generally accepted means of minimizing MMH related injuries is to design MMH tasks so that the demands of the tasks are less than the capacities of the individuals performing these tasks. Task design is dependent, in part, on the availability of comparable data for task demands and worker capacities. The generation of the appropriate data is dependent, in part, on being able to identify the pertinent capacity parameters of manual materials handling activities.

In the past, a substantial effort has been directed at determining ‘safe’ lifting …

Transition Criteria - From A Pit To A Crack, Tarun Goswami, David W. Hoeppner

Biomedical, Industrial & Human Factors Engineering Faculty Publications

A brief review of pitting, which is a localized corrosion process resulting from pitting and fatigue interaction has been conducted in this paper. The transition of a pit to a crack is a very important phenomenon occurring under PCF conditions. Various theories for transition of a pit to a crack were examined within the limits of present understanding and limitations of the models. The transition of a pit to a crack was also discussed for a variety of pit shapes utilizing the pit aspect ratios, defect size and linear elastic fracture mechanics, crack tip characterizing parameters such as Mode I …

Combining Wavelets And Hotelling Transforms In Image Query, Sol Neeman Ph.D.

Engineering Studies Faculty Publications and Creative Works

In the "content based" image query, also referred to as "query by example," "similarity retrieval" or "sketch retrieval," the query image is provided by the user either as a sketch of the object, as the output of a scanner or a video camera. Some of the difficulties associated with content based image query are described in [1], e.g. significant difference between the "query image" and the "target image," artifacts and poor resolution of the query image make a straightforward comparison of images using L1 and l2 metrics not effective.

In [2] a new strategy is suggested based on wavelet decomposition …

Setpoint Tracking Predictive Control In Chemical Processes Based On System Identification, Sinchai Chinvorarat

Mechanical & Aerospace Engineering Theses & Dissertations

A Kraft recovery boiler in a pulp-paper mill provides a means for recovery of the heat energy in spent liquor and recovery of inorganic chemicals while controlling emissions. These processes are carried out in a combined chemical recovery unit and steam boiler that is fired with concentrated black liquor and which produces molten smelt. Since the recovery boiler is considered to be an essential part of the pulp-paper mill in terms of energy resources, the performance of the recovery boiler has to be controlled to achieve the highest efficiency under unexpected disturbances.

This dissertation presents a new approach for combining …

Flange Bolt Failure Analysis, Tarun Goswami

Biomedical, Industrial & Human Factors Engineering Faculty Publications

Failure cause investigation of flange bolts from the bi-axial shaft fatigue test rig was carried out and crack growth rates in combined bending and torsion conditions were determined. Flange bolts are used in gas turbine engines that are pre-torqued exerting bending and torsion fatigue situation arising from high centrifugal stresses. The fracture surface features were characteristic of bending fatigue (BF), where striations were observed, a distinct area within which conjoint bending and torsion fatigue (CBTF) features were documented, and a region between the BF and CBTF, a region of overloading (OL), where ductile dimples were observed. Striations dominated within BF …

An Analysis Of Sustained Collaborative Research Activities Between University Organized Research Units And Industry: A Case Study Of Three Institutions, Elizabeth Taraski Mcdonnell

Seton Hall University Dissertations and Theses (ETDs)

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Loss Detection In The Dairy Industry., Michael Quealy

Theses

In any waste management program, the primary objective must be minimizing product loss without having an affect on product quality. Good waste management is recognized as good manufacturing practice and optimizes the processes to gain the highest possible yield from the available raw materials. A good waste management program must involve the daily monitoring of effluent from the plant for volume and strength. This data needs to be analyzed sufficiently to obtain clear pictures of what problems are present and where they are originating. If this is achieved then the task of reducing the product loss is made much easier. …

Analysis Of Fiber-Reinforced Laminated Momentum Wheel Rotors, Rania Abdel Hassan

Archived Theses and Dissertations

No abstract provided.

Analytical Appraisal Of The Egyptian Privatization Experience, Hanaa Mossad El Habrouk

Archived Theses and Dissertations

No abstract provided.