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Full-Text Articles in Engineering

An Adaptive Tabu Search Heuristic For The Location Routing Pickup And Delivery Problem With Time Windows With A Theater Distribution Application, Robert E. Burks Jr. Sep 2006

An Adaptive Tabu Search Heuristic For The Location Routing Pickup And Delivery Problem With Time Windows With A Theater Distribution Application, Robert E. Burks Jr.

Theses and Dissertations

The time constrained pickup and delivery problem (PDPTW) is a problem of finding a set of routes for a fleet of vehicles in order to satisfy a set of transportation requests. Each request represents a user-specified pickup and delivery location. The PDPTW may be used to model many problems in logistics and public transportation. The location routing problem (LRP) is an extension of the vehicle routing problem where the solution identifies the optimal location of the depots and provides the vehicle schedules and distribution routes. This dissertation seeks to blend the PDPTW and LRP areas of research and formulate a …


Graph Theoretical Analysis Of Network Centric Operations Using Multi-Layer Models, Ann Wong-Jiru Sep 2006

Graph Theoretical Analysis Of Network Centric Operations Using Multi-Layer Models, Ann Wong-Jiru

Theses and Dissertations

As the Department of Defense continues its transformations to a network centric force, evaluating DoD's progression towards net-centricity remains a challenge. This research proposes to extend the Network Centric Operation Common Framework Version 2.0 (draft) with the metrics based in graph theory and, specifically addresses, among other metrics, the measurement of a net-centric force's mission effectiveness. The research incorporates the importance of understanding network topology for evaluating an environment for net-centricity and using network characteristics to help commanders assess the effects of network changes on mission effectiveness. The multi-layered model of Network Centric Operations and interlayer mapping are introduced to …


Technology Transfer: A Qualitative Analysis Of Air Force Office Of Research And Technology Applications, David C. Trexler Jun 2006

Technology Transfer: A Qualitative Analysis Of Air Force Office Of Research And Technology Applications, David C. Trexler

Theses and Dissertations

Everyday within United States Air Forces’ research laboratories there are hundreds of scientists and engineers whose research and development activities contribute to the advancement of science and technology for mankind. The opportunities for successful technology transfer within these research activities are unbounded. This thesis examines the Air Force Office of Research and Technology Applications (ORTA’s) involvement with technology transfer, the complexities they face, the importance of their position, and what best practices ORTAs use to facilitate technology transfer. Air Force concerns and initiatives are detailed to provide perspective on balancing technology transfer with mission requirements and adherence to United States …


Modeling A Reparable Supply Chain And Applying Cpfr Concepts, Sandra A. Mayhall Jun 2006

Modeling A Reparable Supply Chain And Applying Cpfr Concepts, Sandra A. Mayhall

Theses and Dissertations

The Air Force supply chain includes parts required to build, fix, or maintain aircraft delivered to the warfighter to carry out missions. Industry has shown that following Collaborative Planning, Forecasting, and Replenishment (CPFR) concepts, particularly reducing inventory through accurate demand forecasts, has increased profits in part by lowering the holding costs of inventory and increasing sales. This is analogous to the Air Force increasing aircraft availability. There is scant evidence that demand forecasts generated at any level in the Air Force are shared with the intent of coordinating replenishment. This thesis uses a simple discrete-event stochastic simulation model to show …


Reliability Of Systems Using Event Occurrence Networks, Gregory M. Steeger Mar 2006

Reliability Of Systems Using Event Occurrence Networks, Gregory M. Steeger

Theses and Dissertations

The study of a system's reliability has played a crucial role in business and industry since the dawn of modern technology. Current graphical models utilized in reliability theory are limited in that no one model or technique allows for a thorough analysis of system reliability. This research introduces a new graphical model and methodology to be used in the field of reliability that addresses this concern. Event Occurrence Networks (EONs) and their solution methodologies provide an all-inclusive graphical model that allows for the manipulation of several important reliability measures. An EON is a probabilistic network that represents the superposition of …


Technology Transition: Guidance Versus Practice, Walter E. Espy Mar 2006

Technology Transition: Guidance Versus Practice, Walter E. Espy

Theses and Dissertations

The transition of technologies ensures that U.S. warfighters have the necessary capabilities to fight ever increasing and changing global threats. The purpose of this study is to discover to what extent the Air Force Research Laboratory (AFRL) is implementing known technology transition best practices. The research will look at the current guidance on technology transition and determine if it is being used by program managers within AFRL. The study will consider the technology transition process or processes expressly exercised within AFRL by surveying the perspectives and knowledge of program managers. An understanding of this process from the science and technology …


Reducing Uncertainty In Effects-Based Operations, Wilburn B. Mclamb Mar 2006

Reducing Uncertainty In Effects-Based Operations, Wilburn B. Mclamb

Theses and Dissertations

Known as the fog of war, uncertainty has been prevalent in the conduct of military operations throughout human history. Intelligence collection efforts are tasked to reduce this uncertainty through the collection of information. Utilizing Shannon's entropy as a measure of the expected information gain due to an intelligence collection effort, a methodology is developed to prioritize and allocate intelligence assets in an efficient manner. Incorporated in this methodology are target priority and the requirement to reassess dynamic targets. The application area for the methodology is Effects-Based Operations. A generalized state model is developed to conduct adversary system-of-systems analysis. This model …


A Graph Theoretic Analysis Of The Effects Of Organizational Structure On Employee Social Networks, John R. Hutzel Mar 2006

A Graph Theoretic Analysis Of The Effects Of Organizational Structure On Employee Social Networks, John R. Hutzel

Theses and Dissertations

A simulation technique was used to investigate the impacts of organizational structure on an organization's social network. By simulating personnel in an organization as vertices in a graph and the aging of the corporation as the aging of the same graph, the maturation of an organization was realized. The characteristic path length of the graph was measured after each year returning an optimistic average organizational distance. Results include the finding that, per this model, an organization's characteristic path length can drop over 50% in a 20 year period with consideration of edges of all strengths. Next a series of random …


Modeling Network Centric Warfare (Ncw) With The System Effectiveness Analysis Simulation (Seas), Jason B. Honabarger Mar 2006

Modeling Network Centric Warfare (Ncw) With The System Effectiveness Analysis Simulation (Seas), Jason B. Honabarger

Theses and Dissertations

Significant technological advances over the past few decades have fueled the continual and rapid development of an information-based world. Network Centric Warfare (NCW) has become the buzzword of the young millennium within the Department of Defense (DoD) and is quickly becoming a popularly shared vision and rallying cry for force transformation among United States military leaders. An essential element in fully implementing this network-centric way of thinking is to develop useful measures to help gauge the effectiveness and efficiency of both our military networks and our strategic NCW doctrine. The goal of this research is first to provide a comprehensive …


Using Agent-Based Modeling To Search For Elusive Hiding Targets, Jeffrey E. Rucker Mar 2006

Using Agent-Based Modeling To Search For Elusive Hiding Targets, Jeffrey E. Rucker

Theses and Dissertations

The SCUD hunt problem that emerged during Operation Desert Storm has become a source of great interest to major commands like Air Combat Command. One of the metrics used to measure the effectiveness of our operations in a SCUD hunt is time to detect and target. We use the agent-based System Effectiveness and Analysis Simulation (SEAS) to provide a simulation environment in which all the elements of a SCUD hunt mission can adequately be modeled. Our Blue Force agents are modeled as multirole fighters, satellites and unmanned aerial vehicles (UAV) with various sensor capabilities. The Red Force agents are modeled …


A Comparative Usability And End-User Satisfaction Analysis Of Two Geographic Information System (Gis) Applications, Mark E. Barner Mar 2006

A Comparative Usability And End-User Satisfaction Analysis Of Two Geographic Information System (Gis) Applications, Mark E. Barner

Theses and Dissertations

The Air Force has recognized that organizations across Air Force installations often require geospatial information resources or maps to accomplish mission essential tasks. To provide an AF-wide approach to addressing this need, in 2001, the Headquarters Air Force Geo Integration Office formed the USAF GeoBase program. GeoBase is the name given to the Air Force's GIS program. As GeoBase has been implemented across the Air Force, there have been no mandated product standards for GIS applications. This thesis focuses on two different GIS applications being used across the CE community for the management of airfield obstructions. These two applications are …


Combining Quality Of Service And Topology Control In Directional Hybrid Wireless Networks, Michael C. Erwin Mar 2006

Combining Quality Of Service And Topology Control In Directional Hybrid Wireless Networks, Michael C. Erwin

Theses and Dissertations

Recent advancements in information and communications technology are changing the information environment in both quantitative and qualitative measures. The developments in directional wireless capabilities necessitate the ability to model these new capabilities, especially in dynamic environments typical of military combat operations. This thesis establishes a foundation for the definition and consideration of the unique network characteristics and requirements introduced by this novel instance of the Network Design Problem (NDP). Developed are a Mixed-Integer Linear Program (MILP) formulation and two heuristic strategies for solving the NDP. A third solution strategy using the MILP formulation with a degree-constrained Minimum Spanning Tree starting …


Analysis Of Patient Information: An Empirical Modeling Approach, Tony A. Murphy Mar 2006

Analysis Of Patient Information: An Empirical Modeling Approach, Tony A. Murphy

Theses and Dissertations

With rising costs and increasing complexities, many hospitals seek to better understand the intricate details of their operations. Increasingly, these organizations have a strong desire to accurately predict the resources required to effectively treat their patient load. This research investigates patient length-of-stay in a hospital neurological unit using an empirical modeling approach. Factors significantly affecting patient length of stay were identified and used to construct a regression model. The predictive model provides hospital decision makers with a compact tool to input what-if scenarios and predict future patient treatment lengths, thus, allowing the hospital to properly allocate resources.


A Systems Engineering Approach To Integrated Structural Health Monitoring For Aging Aircraft, Alan P. Albert, Efstathios Antoniou, Stephen D. Leggiero, Kimberly A. Tooman, Ramon L. Veglio Mar 2006

A Systems Engineering Approach To Integrated Structural Health Monitoring For Aging Aircraft, Alan P. Albert, Efstathios Antoniou, Stephen D. Leggiero, Kimberly A. Tooman, Ramon L. Veglio

Theses and Dissertations

The United States Air Force and many of its Coalition partners have extended the original service life of some of their aging aircraft due to fiscal constraints. This life extension often requires increased periodic and in-depth inspections; increasing maintenance costs and resulting in longer periods of aircraft downtime. A structural health monitoring system for aging aircraft could reduce the current inspection burden, and thus decrease costs and system downtime. This presentation describes a baseline systems engineering methodology for system definition of an aging aircraft structural health monitoring system. Analysis was performed to quantify the potential benefit a structural health monitoring …


Modeling Urban Warfare: Joint Semi-Automated Forces In Urban Resolve, Alexander B. Anastasiou Mar 2006

Modeling Urban Warfare: Joint Semi-Automated Forces In Urban Resolve, Alexander B. Anastasiou

Theses and Dissertations

The United States military is performing operations in urban environments with increasing frequency. Current Department of Defense doctrine is poorly suited to train and equip today's warriors with the tools and experience necessary to fight and win in modern sprawling cities. In order to "close the gap," the U.S. Joint Forces Command's Joint Experimentation Directorate led an effort to run a massively distributed simulation of a synthetic urban environment utilizing human-in-the-loop operators called URBAN RESOLVE. The synthetic environment simulated the city of Jakarta with over 1,000,000 buildings and structures and over 120,000 civilian entities. A Red force retreated into the …


Optimizing Mean Mission Duration For Multiple-Payload Satellites, John A. Flory Mar 2006

Optimizing Mean Mission Duration For Multiple-Payload Satellites, John A. Flory

Theses and Dissertations

This thesis addresses the problem of optimally selecting and specifying satellite payloads for inclusion on a satellite bus to be launched into a constellation. The objective is to select and specify payloads so that the total lifetime utility of the constellation is maximized. The satellite bus is limited by finite power, weight, volume, and cost constraints. This problem is modeled as a classical knapsack problem in one and multiple dimensions, and dynamic programming and binary integer programming formulations are provided to solve the problem. Due to the computational complexity of the problem, the solution techniques include exact methods as well …


A Risk Assessment Methodology For Divesting Military Capabilities To Allied Nations, Jason A. Gastelum Mar 2006

A Risk Assessment Methodology For Divesting Military Capabilities To Allied Nations, Jason A. Gastelum

Theses and Dissertations

The United States spent over $400 billion dollars on national defense in 2005. Even with support for the war on terrorism still strong, it is doubtful that the U.S. can sustain such a level of defense investment. One strategy to offset the increasing burden of defense spending is to divest the procurement and/or sustainment of individual defense capabilities to allied nations. The decision to divest any capability, however, introduces risk. This thesis presents a methodology to quantify the risk of the decision to divest a military capability to an allied nation, where risk is defined as the set of risk …


Understanding Innovation Adoption In The Air Force, Morgan J. Evans Mar 2006

Understanding Innovation Adoption In The Air Force, Morgan J. Evans

Theses and Dissertations

Innovation adoption has become a critical issue for organizations in both the public and private sectors. The search for competitive advantage has led to the recognition that innovation is a vital ingredient for an organization's survival and profitability in this information age. The United States Air Force is seeking to adapt to this new information age by transforming its business processes in order to sustain its competitive advantage as the world's most respected air force. Adopting innovations and integrating new or improved technologies, capabilities, concepts, and processes into Air Force planning and acquisition activities, organizations, and operations are goals of …


Roadblocks To Software Modernization, Dyan E. Mcclamma Mar 2006

Roadblocks To Software Modernization, Dyan E. Mcclamma

Theses and Dissertations

Failed or troubled modernization efforts, such as the multi-million dollar 1997-2000 ROCC/SOCC failure, are a serious acquisition problem for the Air Force. Using both historical data and a survey of current Air Force software acquisition program key staff, this research examined the Air Forces ability to modernize legacy software systems. The search of historical program data, to identify trends or similarities between known failed software modernization efforts, failed to uncover sufficient data for analysis. This lack of project data indicates a knowledge management issue (i.e. lessons learned are not recorded and stored so that they can be accessed by other …


A Discrete Event Simulation Model For Evaluating Air Force Reusable Military Launch Vehicle Prelaunch Operations, Adam T. Stiegelmeier Mar 2006

A Discrete Event Simulation Model For Evaluating Air Force Reusable Military Launch Vehicle Prelaunch Operations, Adam T. Stiegelmeier

Theses and Dissertations

As the control and exploitation of space becomes more important to the United States military, a responsive spacelift capability will become essential. Responsive spacelift could be defined as the ability to launch a vehicle within hours or days from the time a launch order is given, instead of the weeks or months it takes currently. As the Air Force contemplates moving toward a reusable military launch vehicle (RMLV) capability, it faces key design and ground processing decisions that will affect the vehicle regeneration timeline. This thesis develops a computer simulation model that mimics RMLV prelaunch operations-those activities that take place …


Classification Characteristics Of Carbon Nanotube Polymer Composite Chemical Vapor Detectors, Huynh A. Hinshaw Mar 2006

Classification Characteristics Of Carbon Nanotube Polymer Composite Chemical Vapor Detectors, Huynh A. Hinshaw

Theses and Dissertations

The first step in combating a chemical weapons threat is contamination avoidance. This is accomplished by the detection and identification of chemical agents. The Air Force has several instruments to detect chemical vapors, but is always looking for lighter, faster, and more accurate technology for a better capability. This research is focused on using carbon nanotube polymer composite sensors for chemical detection. More specifically, models are developed to classify three sets of sensor data according to vapor using various multivariate techniques. Also, prediction models of a mixed sensor output are developed using neural networks and regression analysis. The classifiers developed …


Predicting The Effects Of Contingency Contracting On Local Economies, Donald J. Wagoner Mar 2006

Predicting The Effects Of Contingency Contracting On Local Economies, Donald J. Wagoner

Theses and Dissertations

In recent years, Air Force personnel have been deployed in support of contingency operations to various points on the globe. The Department of Defense spends millions of dollars to support and sustain forces during contingency operations. The Air Force deploys Contingency Contracting Officers (CCO) to support personnel during these operations. During a contingency operation contracting officers will normally establish short-term contracts as quickly as possible to meet mission requirements with little concern for the local economy. This research concluded that the actions of Air Force CCOs can affect the local economy in a deployed location. By providing contingency contracting officers …


Implementing Reliability-Centered Maintenance Analysis In A Revised Preventive Maintenance Program For The F-15, Michael H. Martin Mar 2006

Implementing Reliability-Centered Maintenance Analysis In A Revised Preventive Maintenance Program For The F-15, Michael H. Martin

Theses and Dissertations

Reliability-centered maintenance is an approach to analyzing how and when equipment fails in order to maintain a desired level of performance or functionality. It employs the use of failure modes, effects and criticality analysis to rank order potential failures, and combines this rank order with the use of a prescribed decision logic process to determine what preventive maintenance tasks should be performed and when. Reliability-centered maintenance analysis has been used by the United States Navy, the United States Coast Guard, and commercial airlines to develop and update preventive maintenance programs for their aircraft for many years. While the United States …


Discrete Event Simulation Model Of The Ground Maintenance Operations Cycle Of A Reusable Launch Vehicle, John T. Pope Iii Mar 2006

Discrete Event Simulation Model Of The Ground Maintenance Operations Cycle Of A Reusable Launch Vehicle, John T. Pope Iii

Theses and Dissertations

The Air Force uses a family of expendable launch vehicles to meet its spacelift needs. Unfortunately, this method is not responsive: months of preparation are typically required and launch costs are high. Consequently, the Air Force seeks a reusable military launch vehicle that can be launched inexpensively and quickly regenerated between flights. Air Force Research Laboratory personnel desire a tool to help evaluate candidate designs and perform tradeoff studies necessary to acquire a launch vehicle that will achieve Air Force goals. The objective of this research was first to develop a conceptual model of maintenance operations needed to regenerate a …


Assessing Resource Value And Relationships Between Objectives In Effects-Based Operations, Robert D. Jones Mar 2006

Assessing Resource Value And Relationships Between Objectives In Effects-Based Operations, Robert D. Jones

Theses and Dissertations

The purpose of this research was developing techniques to calculate the value of a resource within the context of campaign objectives, to identify competing objectives, and to identify conflicting objectives to improve a commander’s ability to allocate limited resources. A methodology was developed to express a campaign’s objective hierarchy in terms of a set of desired end states for the campaign’s system of systems. Value theory was used to identify the resource's value in terms of the direct and indirect effects that are produced to achieve the campaign’s objectives. Binding resource constraints within an integer program were used to identify …


A Multi-Pass Construction Heuristic For The Aggregated Airlift Problem, Stephen T. O'Leary Mar 2006

A Multi-Pass Construction Heuristic For The Aggregated Airlift Problem, Stephen T. O'Leary

Theses and Dissertations

To support the capabilities for precision strike, close air support, intelligence, surveillance, reconnaissance, air mobility and air refueling the Air Force has over 26,000 Airmen deployed from over 80 military installations to Forward Operating Locations (FOLs) in over 21 countries. This research creates a multi-pass construction heuristic to solve the aggregated airlift problem associated with the transportation of these 26,000 deployed Airmen. We are given a Time Phased Force Deployment Document (TPFDD) containing a list of personnel scheduled for deployment, their base of origin, Point of Debarkation (POD), FOL, and Required Delivery Date (RDD). The goal is to aggregate the …


Optimization Of A Multi-Echelon Repair System Via Generalized Pattern Search With Ranking And Selection: A Computational Study, Derek D. Tharaldson Mar 2006

Optimization Of A Multi-Echelon Repair System Via Generalized Pattern Search With Ranking And Selection: A Computational Study, Derek D. Tharaldson

Theses and Dissertations

With increasing developments in computer technology and available software, simulation is becoming a widely used tool to model, analyze, and improve a real world system or process. However, simulation in itself is not an optimization approach. Common optimization procedures require either an explicit mathematical formulation or numerous function evaluations at improving iterative points. Mathematical formulation is generally impossible for problems where simulation is relevant, which are characteristically the types of problems that arise in practical applications. Further complicating matters is the variability in the simulation response which can cause problems in iterative techniques using the simulation model as a function …


Strategic Airlift En Route Analysis To Support The Global War On Terrorism Using A Value Focused Thinking Approach, Marykathryn W. Tharaldson Mar 2006

Strategic Airlift En Route Analysis To Support The Global War On Terrorism Using A Value Focused Thinking Approach, Marykathryn W. Tharaldson

Theses and Dissertations

The Global War on Terrorism (GWOT) has yielded new challenges to the United States' strategic airlift infrastructure. The network of en-route airfields that serve as refueling and maintenance stops were designed primarily to service relatively static Cold War requirements. However, the GWOT has resulted in the need for an infrastructure that is responsive to a highly dynamic environment. This research uses a "value focused" methodology to identify en-route airfield locations that simultaneously maximize cargo throughput capability while possessing a high degree of adaptability to volatile cargo delivery requirements.


A Methodology For Performing Effects-Based Assessments, Benjamin A. Thoele Mar 2006

A Methodology For Performing Effects-Based Assessments, Benjamin A. Thoele

Theses and Dissertations

In order to bring the doctrine of Effects-Based Operations (EBO) into a fully operational capability, Effects-Based Assessment (EBA) must provide relevant insight to the commander and his planning staff. Assessments of an effects-based plan and execution must include an assessment of the effects of a campaign on the enemy in addition to an assessment of the accomplishment of friendly actions taken to achieve the desired effects. Determining the effects of a campaign requires an analysis of the dynamics of the enemy systems. EBA must be able to recognize the states of the enemy's systems as the system states change over …


Hazardous Materials Transportation: A Meta-Analysis Of State Level Policy And Regulations, David J. Pastika Mar 2006

Hazardous Materials Transportation: A Meta-Analysis Of State Level Policy And Regulations, David J. Pastika

Theses and Dissertations

Every day, over 800,000 hazmat transactions take place across the United States. This segment of transportation is expected to grow at a modest two percent a year for the foreseeable future but differences of regulations between the state and Federal level have been a growing concern for both the government and members of the hazmat industry. A patchwork of often inconsistent permits, registration requirements, and hazmat organizational structures at the state level often create barriers to the efficient means of commerce for hazmat carriers and shippers. This thesis explores the history of hazardous regulations since de-regulation of the trucking industry …