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Articles 241 - 270 of 275
Full-Text Articles in Engineering
Strategic Airlift En Route Analysis To Support The Global War On Terrorism Using A Value Focused Thinking Approach, Marykathryn W. Tharaldson
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.
Development Of A Comprehensive Digital Avionics Curriculum For The Aeronautical Engineer, Thomas W. Hofer
Development Of A Comprehensive Digital Avionics Curriculum For The Aeronautical Engineer, Thomas W. Hofer
Theses and Dissertations
The purpose of this research was to develop a comprehensive digital avionics curriculum for aeronautical engineering students at AFIT. Due to the closing of the aeronautical engineering program at the Naval Postgraduate School, and the subsequent requirement to establish a digital avionics specialty course sequence at AFIT, a mature avionics curriculum does not yet exist that satisfies the needs of graduates who will serve as aeronautical engineers involved with the development, integration, testing, fielding, and supporting of military avionics systems as part of the overall aircraft system. Research was conducted through a comprehensive literature review and the use of a …
Predicting The Effects Of Contingency Contracting On Local Economies, Donald J. Wagoner
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 …
Preliminary Design Approach For Prosthetic Ankle Joints Using Compliant Mechanisms, Jason Matthew Wiersdorf
Preliminary Design Approach For Prosthetic Ankle Joints Using Compliant Mechanisms, Jason Matthew Wiersdorf
Theses and Dissertations
The objective of this thesis is to develop design approaches and models for prosthetic ankle joints using kinematic models of the human ankle and compliant mechanisms technology. Compliant mechanisms offer several potential design advantages over traditional rigid-body designs including high reliability and low cost. These design advantages are ideal for use in prosthetics. Some prosthetic ankle/foot systems currently on the market have multiple degrees of freedom yet are expensive. Additionally, even though these systems have multiple degrees of freedom, none of them are designed after the actual movements of the biological ankle. In this thesis a two, single degree-of-freedom hinge …
Developing A Gis And Hydrological Modeling Approach For Sustainable Water Resources Management In The West Bank -- Palestine, Walid Wajeeh Sabbah
Developing A Gis And Hydrological Modeling Approach For Sustainable Water Resources Management In The West Bank -- Palestine, Walid Wajeeh Sabbah
Theses and Dissertations
This research deals with setting up a GIS and hydrological modeling based approach for sustainable water resources management in the West Bank of Palestine. This water sustainability approach took into consideration the water balance, the social, the economic, the demographic, the environmental, and the institutional components in order to enhance and promote the sustainable development in Palestine, both on the short and long runs. To evaluate the water balance component, a methodology was introduced to create the Water Sustainability Map (WSM). Since the groundwater is currently the only accessible water source by the Palestinians, the WSM is represented by the …
Strategic Airlift En Route Analysis And Considerations To Support The Global War On Terrorism, Michael C. Sere
Strategic Airlift En Route Analysis And Considerations To Support The Global War On Terrorism, Michael C. Sere
Theses and Dissertations
The Global War on Terrorism has mandated the need for additional global en route airfields. En route airfields consist of bases that are strategically located at intermediate locations between the Continental United States and the intended theater of operations. These airfields serve as refueling, crew staging, or maintenance stops for strategic airlift aircraft flying transoceanic routes. The focus of this study is to examine concepts to meet this need and to address important aspects that should be considered in devising new en route strategies. Based on various important factors associated with potential en route airfields, a goal programming methodology was …
A Knowledge Matrix Modeling Of The Intelligence Cycle, Kevin J. Whaley
A Knowledge Matrix Modeling Of The Intelligence Cycle, Kevin J. Whaley
Theses and Dissertations
This effort models information flow through the United States Intelligence Community's Intelligence Cycle using a knowledge matrix methodology. The knowledge matrix methodology takes explicit data from multiple sources and fuses that data to measure a current level of knowledge about a target, or situation. Knowledge matrices are used to develop a measure of user-needs satisfaction. User-needs satisfaction compares requested levels of knowledge to a probability of collecting that knowledge within a designated timeframe. This effort expands the work done by Captain Carl Pawling in his March 2004 thesis, Modeling and Simulation of the Military Intelligence Process, by modeling intelligence as …
An Evaluation Of Contingency Construction Methods Using Value Focused Thinking, John E. Tyron
An Evaluation Of Contingency Construction Methods Using Value Focused Thinking, John E. Tyron
Theses and Dissertations
Rapid Engineering Deployable, Heavy Operational Repair Squadron, Engineer (RED HORSE) Squadrons are 400-person, self-contained, combat engineer units that provide deployable and flexible expert construction capability for the United States Air Force. To help meet Air Force mission requirements, RED HORSE units currently employ a variety of traditional and innovative construction methods. But their alternatives-focused decision analysis approach to method selection limits their decision to known alternatives and may not fully achieve all of their objectives. This research developed a generic value-focused thinking (VFT) decision analysis model to help RED HORSE evaluate and select contingency construction methods. Eight alternatives were generated …
Characterization Of Fluoropolymer Powders Made By Supercritical Assisted Mixing With Crystalline Additives, Ntoh Atem-Tambe
Characterization Of Fluoropolymer Powders Made By Supercritical Assisted Mixing With Crystalline Additives, Ntoh Atem-Tambe
Theses and Dissertations
This research project investigates a new technique to efficiently mix crystalline solid additives with polymers by gentle ball milling with steel balls in the presence of carbon dioxide (C02) at 17 to 30°C and 1300 to 2500 psig. As the ball milling system is agitated, the steel balls transfer mechanical energy to the fluoropolymer and additive thereby converting them to powders. C02 is added into the chamber to expand the polymer and make it amenable to impregnation by the additive. At the end of the mixing process, a free flowing powder is produced consisting of the additive coated with fluoropolymer. …
A New Method For Melt Detection On Antarctic Ice-Shelves And Scatterometer Calibration Verification, Lukas Brad Kunz
A New Method For Melt Detection On Antarctic Ice-Shelves And Scatterometer Calibration Verification, Lukas Brad Kunz
Theses and Dissertations
Ku-band dual-polarization radar backscatter measurements from the SeaWinds on QuikScat scatterometer and microwave radiometer measurements from the Special Sensor Microwave/Imager (SSM/I) are used to determine periods of surface melt and freeze in the Antarctic ice-shelves. The normalized radar backscatter (sigma-0) and backscatter polarization ratio (PR) are used in the maximum likelihood estimation of the ice-state. This method is used to infer the daily ice-surface conditions for 25 selected study points located on the Ronne, Ross, Larsen, Fimbul, Amery, and Shackleton Ice-shelves. The temporal and spatial variations of the radar response are also observed for various neighborhood sizes surrounding each given …
Modeling And Analysis Of Post-Conflict Reconstruction, Damon B. Richardson
Modeling And Analysis Of Post-Conflict Reconstruction, Damon B. Richardson
Theses and Dissertations
The forces at play in reconstruction operations are a complex system of time phased interlocking cause and effect relationships that are not thoroughly understood. A model capable of capturing the general dynamics involved in post-conflict reconstruction would provide insight to decision makers regarding potential policy alternatives. This research effort demonstrates the viability of using systems dynamics modeling techniques to simulate the establishment of public order and safety in a post-conflict reconstruction operation (Phase IV operations). A high level generic framework is developed that can be used as a general template for modeling post-conflict reconstruction. It is then demonstrated with a …
Spatially Varying Threshold Models For The Automated Segmentation Of Radiodense Tissue In Digitized Mammograms, Richard Edson Eckert Iii
Spatially Varying Threshold Models For The Automated Segmentation Of Radiodense Tissue In Digitized Mammograms, Richard Edson Eckert Iii
Theses and Dissertations
The percentage of radiodense (bright) tissue in a mammogram has been correlated to an increased risk of breast cancer. This thesis presents an automated method to quantify the amount of radiodense tissue found in a digitized mammogram. The algorithm employs a radial basis function neural network in order to segment the breast tissue region from the remainder of the X-ray. A spatially varying Neyman-Pearson threshold is used to calculate the percentage of radiodense tissue and compensate for the effects of tissue compression that occurs during a mammography procedure. Results demonstrating the efficacy of the technique are demonstrated by exercising the …
Selecting Appropriate Product Concepts For Manufacture In Developing Countries, Danielle Johnson
Selecting Appropriate Product Concepts For Manufacture In Developing Countries, Danielle Johnson
Theses and Dissertations
There is a noticeable lack of production of indigenously engineered and manufactured products in Less Developed Countries (LDC's). Few products developed in these LDC's could be viable in competitive markets or even sold as components and supplies to other manufacturers of competitive goods. Assumintg that these less developed countries do not innovate and manufacture because they cannot, the next logical question to ask is why can they not?
This thesis looks at the problems of manufacture and design in LDC's from the standpoint of Product Development. It begins by looking at development theories, namely top down and bottom up and …
Experimental Demonstration Of An Algorithm To Detect The Presence Of A Parasitic Satellite, Vincent J. Dabrowski
Experimental Demonstration Of An Algorithm To Detect The Presence Of A Parasitic Satellite, Vincent J. Dabrowski
Theses and Dissertations
Published reports of microsatellite weapons testing have led to a concern that some of these "parasitic" satellites could be deployed against US satellites to rendezvous dock and then disrupt, degrade disable or destroy the system. An effective detection method is essential. Various sensing solutions were investigated including visual, impact, and dynamic techniques. Dynamic detection, the most effective solution, was further explored. A detection algorithm was constructed and validated on the Air Force Institute of Technology's ground-based satellite simulator, SIMSAT. Results indicate that microsat microsatellites rigidly connected to a satellite can be detected with a series of small identical maneuvers utilizing …
Calculation Of The Actual Cost Of Engine Maintenance, Oguz Ezik
Calculation Of The Actual Cost Of Engine Maintenance, Oguz Ezik
Theses and Dissertations
The cost of military operations has been difficult to determine, yet considered of high importance. The cost of an operation is largely dependent upon the answers to subordinate questions involving the discrete costs of military activities, like supporting individual items, While different cost estimates have received attention from the media, the question arises as to how accurate these figures are, There have been numerous studies performed by the Operations Research analysts to minimize costs while allocating scarce resources, However, the values of these studies are dependent upon whether or not the cost figures used are sufficiently "true" or accurate, This …
Modeling Homeland Security: A Value Focused Thinking Approach, Kristopher A. Pruitt
Modeling Homeland Security: A Value Focused Thinking Approach, Kristopher A. Pruitt
Theses and Dissertations
The events of September 11, 2001 have propelled the topic of homeland security to the forefront of national concern. The threat of terrorism within the United States has reached an unprecedented level. The pervasive vulnerabilities of the nation's critical infrastructure coupled with the destructive capabilities and deadly intentions of modern terrorists pose extraordinary risks. The United States must mitigate these risks while at the same time balancing the associated costs and impact on civil liberties. Currently, the United States lacks effective methods and measure for assessing the security of the homeland from acts of terrorism. This study outlines a first …
Automated Segmentation Of Radiodense Tissue In Digitized Mammograms Using A Constrained Neyman-Pearson Classifier, Jeremy Thomas Neyhart
Automated Segmentation Of Radiodense Tissue In Digitized Mammograms Using A Constrained Neyman-Pearson Classifier, Jeremy Thomas Neyhart
Theses and Dissertations
Breast cancer is the second leading cause of cancer related mortality among American women. Mammography screening has emerged as a reliable non-invasive technique for early detection of breast cancer. The radiographic appearance of the female breast consists of radiolucent (dark) regions and radiodense (light) regions due to connective and epithelial tissue. It has been established that the percentage of radiodense tissue in a patient's breast can be used as a marker for predicting breast cancer risk. This thesis presents the design, development and validation of a novel automated algorithm for estimating the percentage of radiodense tissue in a digitized mammogram. …
Commercial Regional Space/Airborne Imaging, Ugur Akyazi, Ali Durmus, Birce Boga Bakirli, Arif Arin
Commercial Regional Space/Airborne Imaging, Ugur Akyazi, Ali Durmus, Birce Boga Bakirli, Arif Arin
Theses and Dissertations
In this work goal programming is used to solve a minimum cost multicommodity network flow problem with multiple goals. A single telecommunication network with multiple commodities (e.g., voice, video, data, etc.) flowing over it is analyzed. This network consists of: linear objective function, linear cost arcs, fixed capacities, specific origin-destination pairs for each commodity. A multicommodity network flow problem with goals can be successfully modeled using linear goal programming techniques. When properly modeled, network flow techniques may be employed to exploit the pure network structure of a multicommodity network flow problem with goals. Lagrangian relaxation captures the essence of the …
An Analysis Of Civil Engineer Officer Contingency Training, Rusty J. Vaira
An Analysis Of Civil Engineer Officer Contingency Training, Rusty J. Vaira
Theses and Dissertations
The primary objective of this research was to investigate the current overall civil engineer officer contingency training program and determine if civil engineer officers think it is adequately preparing them to perform in a contingency environment. In accomplishing this objective, this research explored the perceptions that officers have about the contingency training that is available through three primary training programs (Home Station Training, Silver Flag training, and Civil Engineer and Services School training). The overall intent of the author was to gauge how the officers feel about their contingency training and offer some suggestions on how to improve the training. …
Determining The Aircraft Requirement For Turkish Air Mobility System, Mehmet M. Ari
Determining The Aircraft Requirement For Turkish Air Mobility System, Mehmet M. Ari
Theses and Dissertations
Aircraft technology develops very rapidly. To keep up with the modem technology, we should update our systems and material over time. In order to do so, we should keep track of modem technologies, and implement them in our military. Turkish Air Force Command operates a vital logistical system for which routing and scheduling are done on a weekly basis. This research reviewed weekly schedules and determined the average required weekly missions which would be flown during the week. By carefully examining the job - machine formulation, this research devised a method for determining the aircraft required to perform for weekly …
Locating Search And Rescue Stations In The Aegean And Western Mediterranean Regions Of Turkey, Melih M. Basdemir
Locating Search And Rescue Stations In The Aegean And Western Mediterranean Regions Of Turkey, Melih M. Basdemir
Theses and Dissertations
The service of present Search and Rescue (SAR) stations in the Aegean and the Western Mediterranean regions of Turkey are not sufficient to meet the demands of the Turkish Air Force. This research seeks to find the optimum location of new SAR stations. The number of SAR stations required to cover all areas of operation becomes a very decisive element in finding the optimal coverage of the operation area by these stations. The problem of finding the optimum SAR locations can he modeled as a maximal covering location problem (MCLP). Additional constraints are added to set standards on various issues …
A Performance Analysis Of Dynamic Routing Algorithms In An Iridium-Like Low Earth Orbit Satellite System, Stephen R. Pratt
A Performance Analysis Of Dynamic Routing Algorithms In An Iridium-Like Low Earth Orbit Satellite System, Stephen R. Pratt
Theses and Dissertations
This research presents a first of its kind comparative analysis of the Extended Bellman-Ford and Darting algorithms, using the Iridium low earth orbit (LEO) satellite system configuration for the simulation environment. The algorithms are compared to one another via discrete-event computer simulation and evaluated based on their ability to route real-time voice communications under low, medium, and high network loading conditions. The algorithms' ability to meet real-time voice constraints is evaluated with a full and degraded satellite constellation using an algorithmic satellite removal method. The investigation results indicate that both algorithms are suitable for use in a LEO environment and …
A Validation Assessment Of Thunder 6.5'S Intelligence, Surveillance, And Reconnaissance Module, Francine N. Nelson
A Validation Assessment Of Thunder 6.5'S Intelligence, Surveillance, And Reconnaissance Module, Francine N. Nelson
Theses and Dissertations
A validation assessment of THUNDER 6.5's Intelligence, Surveillance, and Reconnaissance (ISR) module is accomplished using formulational and experimental validation techniques. A comparison of ISR purposes and processes according to military doctrine is made with the purposes and processes of ISR implemented within THUNDER 6.5. This comparison provides an overview of the process, an understanding of the level of aggregation within THUNDER, insight into possible problem areas in THUNDER, and a basis for improving THUNDER ISR processes. Sensitivity analysis of the ISR parameters as they relate to the Quality, Quantity, and Timeliness of ISR is also presented to provide insight into …
A Comparative Analysis Of The Iridium® And Globalstar® Satellite Transmission Paths, Kenneth E. Crowe
A Comparative Analysis Of The Iridium® And Globalstar® Satellite Transmission Paths, Kenneth E. Crowe
Theses and Dissertations
Globalstar and Iridium will provide valuable global communications assets for business, humanitarian aid and military operations. However, the level of coverage and the quality of the transmission path of these systems are strongly dependent on the latitude of the user and, due to their orbital characteristics, both systems provide reduced levels of coverage at low latitudes. Additionally, the L- and S-Band frequencies utilized by these systems are prone to ionospheric interference at low latitudes. The results of extensive simulation analysis indicate that the Globalstar constellation architecture provides a considerably better transmission path than Iridium's in several important areas, including path …
Hydrocatalysis: A New Energy Paradigm For The 21st Century, Peter Mark Jansson
Hydrocatalysis: A New Energy Paradigm For The 21st Century, Peter Mark Jansson
Theses and Dissertations
This thesis will review the problems of worldwide energy supply, describe the current technologies that meet the energy needs of our industrial societies, summarize the environmental impacts of those fuels and technologies and their increased use by a growing global and increasingly technical economy. This work will also describe and advance the technology being developed by BlackLight Power, Inc. [BLP], a scientific company located in Malvern, Pennsylvania. BLP's technology purports to offer commercially viable and useful heat generation via a previously unrecognized natural phenomenon - the catalytic reduction of the hydrogen atom to a lower energy state. A review of …
Analysis Of A Methodology For Linear Programming Optimality Analysis, Chanseok Jeong
Analysis Of A Methodology For Linear Programming Optimality Analysis, Chanseok Jeong
Theses and Dissertations
The methodology of Johnson, Baner, Moore, and Grant can be applied to large scale linear programming models. A methodology for optimality analysis of linear programs was developed to create metamodels using response surface methodology techniques such as experimental design and least squares regression. A metamodel consists of a simple equation which is able to predict the optimal objective function value of a linear program. What is needed is some large scale application of the techniques to verify how accurate they are. In the research, I plan to use the large scale LP model, STORM. I use the "Hot Start" idea …
Investigation Of Radio Wave Propagation In The Martian Ionosphere Utilizing Hf Sounding Techniques, Robert J. Yowell
Investigation Of Radio Wave Propagation In The Martian Ionosphere Utilizing Hf Sounding Techniques, Robert J. Yowell
Theses and Dissertations
This thesis presents a preliminary design of an ionospheric sounder to be carried aboard one or more of NASA's Mars Surveyor landers. Past Russian and American probes have indicated the existence of an ionosphere, but none of these missions remotely sensed this atmospheric layer from the surface. The rationale for utilizing a surface-based Martian ionospheric sounder is discussed. Based on NASA's choice of launch vehicle and power source, a low-weight, low-powered Chirp sounder using a horizontally-polarized dipole antenna is recommended for the sounder experiment. The sounder experiment should be conducted for at least one Martian year, in order to investigate …
Standardization Of Protocol For The Sampling, Testing And Abatement Of Asbestos Containing Joint Compound, Gary J. Schneider
Standardization Of Protocol For The Sampling, Testing And Abatement Of Asbestos Containing Joint Compound, Gary J. Schneider
Theses and Dissertations
This study investigated the differing regulatory guidelines from the Occupational Safety and Health Administration and the Environmental Protection Agency concerning the abatement of Asbestos Containing Joint Compound (ACJC). The specific interest was whether or not adequate protection was being afforded demolition workers when exposed to working with ACJC materials that contain less than 1.0 percent asbestos. A spreadsheet was written to estimate the exposure scenario which might be experienced within a given room size on a demolition or renovation jobsite. Spreadsheets were calculated for ACJC with an asbestos content of 0.1 to 0.9 percent in 0.1 increments for rooms ranging …
Noise Reduction For Speech Enhancement Using Non-Linear Wavelet Processing, Hassan Dehmani
Noise Reduction For Speech Enhancement Using Non-Linear Wavelet Processing, Hassan Dehmani
Theses and Dissertations
The problem of speech enhancement presents many obstacles in the speech processing field. This thesis develops several speech de-noising systems that can be used in the time, fourier, and wavelet domains. We present two thresholding techniques soft and hard. The application of these thresholding techniques to noisy speech data is discussed. The combination of both wavelets and the Fourier domains with noisy phase restoration proves to yield the best results in terms of intelligibility. Informal listening tests were conducted in order to compare the effects and differences between the speech de-noising systems.
An Independent Evaluation Of Information Systems Support Of The Joint Forces Air Component Commander Concept Of Operations, Gregory R. Kincaid, Richard A. Poligala
An Independent Evaluation Of Information Systems Support Of The Joint Forces Air Component Commander Concept Of Operations, Gregory R. Kincaid, Richard A. Poligala
Theses and Dissertations
This study examines automated Air Tasking Order (ATO) generation and dissemination under the Joint Forces Air Component Commander (JFACC) concept, focusing on an evaluation of information systems support given the differing service philosophies concerning control of tactical air assets. Current Department of Defense doctrine identifies the Contingency Tactical Air Control System Automated System (CTAPS) as the standard automated system for Theater Battle Management planning for the JFACC. To achieve service interoperability, the doctrine requires the use of CTAPS for ATO generation and dissemination when joint operations are conducted under the JFACC concept. A problem arises in that CTAPS is developed …