Open Access. Powered by Scholars. Published by Universities.®

Engineering Commons™

Open Access. Powered by Scholars. Published by Universities.®

2003

Discipline
Institution
Keyword
Publication
Publication Type
File Type

Articles 1111 - 1140 of 2071

Full-Text Articles in Engineering

Analysis Of Air Force Civil Engineering Strategic Planning, Francis J. Mondo Jr. Mar 2003

Analysis Of Air Force Civil Engineering Strategic Planning, Francis J. Mondo Jr.

Theses and Dissertations

Several organizations within the Department of Defense, including the Air Force Civil Engineer, are actively engaged in strategic planning in an effort to create a roadmap for future capabilities and performance. The objective of this research was to analyze the strategic planning process of the Air Force Civil Engineer (CE) as well as the effectiveness of the Civil Engineer Strategic Plan (CESP). The methodology used to complete this analysis was conducted in two distinct phases: 1) process modeling and evaluation, and 2) performance measure evaluation. The first phase compared the CE strategic planning process to a theoretical planning model developed …

Go to article

Ultra Wide Band Multiple Access Performance Using Th-Ppm And Ds-Bpsk Modulations, Courtney M. Canadeo Mar 2003

Ultra Wide Band Multiple Access Performance Using Th-Ppm And Ds-Bpsk Modulations, Courtney M. Canadeo

Theses and Dissertations

The increasing demand for portable, high data rate communications has focused much attention on wireless technology. Ultra Wide Band (UWB) waveforms have the ability to deliver megabits of information while maintaining low average power consumption. In accordance with recent FCC ruling, UWB systems are now allowed to operate in the unlicensed spectrum of 3.1 to 10.6 GHz, motivating renewed interest in the forty year old concept of impulse radio. Gaussian monocycles produce UWB waveforms occupying large bandwidths with multiple access (MA) capability enabled by spread spectrum techniques. Time Hopping (TH) and Direct Sequence (DS) modulations are considered here for UWB …

Go to article

Mechanical Computing In Microelectromechanical Systems (Mems), Kenneth C. Bradley Mar 2003

Mechanical Computing In Microelectromechanical Systems (Mems), Kenneth C. Bradley

Theses and Dissertations

Mechanical computing devices in polysilicon-based microelectromechanical systems (MEMS) were designed with the goal of developing computing devices for harsh environments, such as those with high dose radiation and high temperatures, as well as devices that may be able to interface with molecular or biological computer systems. The devices that were designed include both analog and digital computing devices. The analog devices include integrators, differentials (summers), multipliers, and those that perform trigonometric functions. The digital devices that were designed are inverters, NAND, NOR, and XOR logic gates. Analog-to-digital (A-to-D) and digital-to-analog (D-to-A) converters were also designed. The designs were submitted to …

Go to article

Theoretical Analysis Of Information Watermarking In Wavelet-Based Video Compression, Brendan K. Casey Mar 2003

Theoretical Analysis Of Information Watermarking In Wavelet-Based Video Compression, Brendan K. Casey

Theses and Dissertations

Embedding audio bits into images for transmission of video data alleviates the synchronization problem common in video transmission techniques. We continue work combining audio or other information bits and images into one file using digital watermarking techniques to correct the synchronization problem. The system compresses the file by using wavelet image coefficients and implementing bit plane coding. Our research encompasses incorporating five free variables into the watermark/compression technique. These variables are watermark robustness, number of coding iterations, number of image coefficients, number of watermarked information bits, and number of watermarked error correcting bits. By altering these variables, four measurements of …

Go to article

Tightly-Coupled Image-Aided Inertial Navigation System Via A Kalman Filter, Michael G. Giebner Mar 2003

Tightly-Coupled Image-Aided Inertial Navigation System Via A Kalman Filter, Michael G. Giebner

Theses and Dissertations

Inertial navigation systems and GPS systems have revolutionized the world of navigation. Inertial systems are incapable of being jammed and are the backbone of most navigation systems. GPS is highly accurate over long periods of time, and it is an excellent aid to inertial navigation systems. However, as a military force we must be prepared to deal with the denial of the GPS signal. This thesis seeks to determine it, via simulation, it is viable to aid an INS with visual measurements.

Go to article

Using The Gps To Improve Trajectory Position And Velocity Determination During Real-Time Ejection Seat Design, Test And Evaluation, Christina G. Schutte Mar 2003

Using The Gps To Improve Trajectory Position And Velocity Determination During Real-Time Ejection Seat Design, Test And Evaluation, Christina G. Schutte

Theses and Dissertations

Test and evaluation of the United States Air Force’s latest aircraft escape system technology requires accurate position and velocity profiles during each test to determine the relative positions between the aircraft, ejection seat, manikin and the ground. Current rocket sled testing relies on expensive ground based multiple camera systems to determine the position and velocity profiles. While these systems are satisfactory at determining seat and manikin trajectories for sled testing, their accuracy decreases when they are used for in-flight testing, especially at high altitudes. This research presents the design and test results from a new GPS-based system capable of monitoring …

Go to article

Redundant Discrete Wavelet Transform Based Super-Resolution Using Sub-Pixel Image Registration, Daniel L. Ward Mar 2003

Redundant Discrete Wavelet Transform Based Super-Resolution Using Sub-Pixel Image Registration, Daniel L. Ward

Theses and Dissertations

The limited resolution of video imagery taken by aircraft, over geographical areas of interest, hinders the accurate extraction of useful information. The frame resolution of the video is determined by the camera that created it. Information exists about the camera which can be used to increase frame resolution beyond the resolution capability of the camera. This is achieved by a process called super-resolution, which uses multiple low-resolution video frames to create one high-resolution image.

Go to article

Development Of Variable Slope Piecewise-Based Brown Symbols For Application To Nonlinear Ambiguity Suppression, John Kurian Mar 2003

Development Of Variable Slope Piecewise-Based Brown Symbols For Application To Nonlinear Ambiguity Suppression, John Kurian

Theses and Dissertations

In 1962, Palermo used two conjugate Linear Frequency Modulated (LFM) pulses to demonstrate a Non-linear Ambiguity Suppression (NLAS) technique to reduce ambiguous energy in radar returns. Using conjugate LFM pulse coding does not readily extend to larger symbol families and thus is severely limited for M-channel (M> 2) NLAS applications. Larger families of optimal mutually dispersible codes with bigger time bandwidth products are needed to achieve the desired M-fold range ambiguity reduction. Using correlation function the time duration as an optimization metric, the recently proposed Brown's theorem formulates a deterministic process for designing optimal mutually dispersible symbol sets of arbitrary …

Go to article

Gaussian Mixture Reduction Of Tracking Multiple Maneuvering Targets In Clutter, Jason L. Williams Mar 2003

Gaussian Mixture Reduction Of Tracking Multiple Maneuvering Targets In Clutter, Jason L. Williams

Theses and Dissertations

The problem of tracking multiple maneuvering targets in clutter naturally leads to a Gaussian mixture representation of the Provability Density Function (PDF) of the target state vector. State-of-the-art Multiple Hypothesis Tracking (MHT) techniques maintain the mean, covariance and probability weight corresponding to each hypothesis, yet they rely on ad hoc merging and pruning rules to control the growth of hypotheses.

Go to article

Outsourcing Information Technology And The Insider Threat, Valerie L. Caruso Mar 2003

Outsourcing Information Technology And The Insider Threat, Valerie L. Caruso

Theses and Dissertations

As one of our nation's top critical infrastructures, telecommunications is an essential element of many aspects of our lives upon which we, as a society, are becoming increasingly dependent. Computers, digital telephone switches, and interconnected information technology (IT) systems impact finances, travel, infrastructure management, and missions of national defense. This research examined whether the trend in increased outsourcing of information technology systems is a significant contributing factor to a reportedly increasing amount of insider attacks. In light of changing social, global economic, and technological conditions, the paradigm in which risk analysis, management practices, and operational and personnel security practices are …

Go to article

Characterizing Data Streams Over Ieee 802.11b Ad-Hoc Wireless Networks, John T. Wagnon Mar 2003

Characterizing Data Streams Over Ieee 802.11b Ad-Hoc Wireless Networks, John T. Wagnon

Theses and Dissertations

Soon, advancements in data encryption technology will make real-time decryption of the contents of network packets virtually impossible. This research anticipates this development and extracts useful information based on packet level characteristics. Distinguishing characteristics from e-mail, HTTP, print, and FTP applications are identified and analyzed. The analysis of collected data from an ad-hoc wireless network reveals that distinguishing characteristics of network traffic do indeed exist. These characteristics include packet size, packet frequency, inter-packet correlation, and channel utilization. Without knowing the contents of packets or the direction of the traffic flow, the applications accessing the wireless network can be determined.

Go to article

Detection Of Special Nuclear Material With High Purity Germanium (Hpge) And Mercuric Iodide (Hgi2) Gamma Detectors, Michael B. Nelson Mar 2003

Detection Of Special Nuclear Material With High Purity Germanium (Hpge) And Mercuric Iodide (Hgi2) Gamma Detectors, Michael B. Nelson

Theses and Dissertations

The Defense Threat Reduction Agency (DTRA) contracted for two gamma radiation detectors: mercuric iodide (HgI2) and electromechanically cooled (EMC) high purity germanium (HPGe) to support arms control inspection efforts. This project investigated whether these detectors could measure the quality and quantity of special nuclear material (SNM), particularly Pu-239 for the treaty verification mission. The project investigated two areas of detector capabilities: 1) HgI2 and HPGe detector performance necessary to characterize the quality of plutonium and the presence of shielding materials and 2) HgI2 and EMC HPGe detector performance degradation by high noise levels and EMC HPGe …

Go to article

Investigation Of A Passive, Temporal, Neutron Monitoring System That Functions Within The Confines Of Start I, Stephanie Vaughn Mar 2003

Investigation Of A Passive, Temporal, Neutron Monitoring System That Functions Within The Confines Of Start I, Stephanie Vaughn

Theses and Dissertations

This study is an investigation of the theoretical and experimental possibilities of using activation foils to detect and monitor special nuclear material for treaty monitoring purposes. None of the experiments demonstrated sufficient sensitivity to detect the target flux of 0.5 neutrons/cu cm--sec. The target flux could be detectable, if the limit of detection had been reduced by a factor of 4 to 6. However, many issues identified could enhance the sensitivity including: increasing foil size, increasing detector efficiency, and optimizing foil selection. The theoretical portion focused on gold, silver, indium, europium, and gadolinium foils and determined the minimum flux detectable, …

Go to article

Assessing The Treatment Of Airborne Tactical High Energy Lasers In Combat Simulations, Maurice C. Azar Mar 2003

Assessing The Treatment Of Airborne Tactical High Energy Lasers In Combat Simulations, Maurice C. Azar

Theses and Dissertations

In March 2000, the High Energy Laser Executive Review Panel presented the Department of Defense Laser Master Plan, which reported that HEL weapons are ready for offensive and defensive applications. One candidate platform capable of performing some of the reported applications is the Advanced Tactical Laser (ATL), an Advanced Concept Technology Demonstration program which places a high energy laser weapon on a tactical aircraft, such as the V-22, C-130, or H-47. A way of assessing the utility of a new weapon system and the benefits of its inclusion in the force structure is the use of combat models. This research …

Go to article

Simulation Of Autonomic Logistics System (Als) Sortie Generation, Paul D. Faas Mar 2003

Simulation Of Autonomic Logistics System (Als) Sortie Generation, Paul D. Faas

Theses and Dissertations

The Air Force needs tools for analysis and evaluation of new logistic operational concepts. The purpose of this research was to conflict a discrete event simulation model of the aircraft sortie generation process to permit what-if analyses of these concepts. The current Air Force logistics operations system is reactive in nature meaning that after the aircraft detects a part failure, the maintenance person must perform fault isolation procedures and then steps are taken to repair or replace the faulty item. The Autonomic Logistics System (ALS) concept changes the reactive process into a proactive one with the employment of technologies such …

Go to article

Using Neural Networks For Estimating Cruise Missile Reliability, Donald L. Hoffman Mar 2003

Using Neural Networks For Estimating Cruise Missile Reliability, Donald L. Hoffman

Theses and Dissertations

ACC believes its current methodology for predicting the reliability of its Air Launched Cruise Missile (ALCM) and Advanced Cruise Missile (ACM) stockpiles could be improved. They require a predictive model that delivers the best possible 24-month projection of cruise missile reliability using existing data sources, collection methods and software. It should be easily maintainable and developed to allow a layperson to enter updated data and receive an accurate reliability prediction. The focus of this thesis is to improve upon free flight reliability, although the techniques could also be applied to the captive carry portion of the missile reliability equation. The …

Go to article

Physical Fitness And The Expeditionary Air Force, Elizabeth T. Lewis Mar 2003

Physical Fitness And The Expeditionary Air Force, Elizabeth T. Lewis

Theses and Dissertations

The Air Force is constantly evolving. With the many changes and the Expeditionary Air Force structure put in place, it is more important now than ever that the Air Force has a physical fitness program to keep its members healthy and productive. By doing this, it can ensure success in completing the Air Force mission while keeping the organization at the highest level of readiness possible. This thesis looks at what the Air Force values in having a fitness program. These values are taken from Air Force doctrine and related instructions. Using these values, fitness programs can be evaluated to …

Go to article

Use Of Multivariate Techniques To Validate And Improved The Current Usaf Pilot Candidate Selection Model, Ross A. Keener Mar 2003

Use Of Multivariate Techniques To Validate And Improved The Current Usaf Pilot Candidate Selection Model, Ross A. Keener

Theses and Dissertations

The Pilot Candidate Selection Method (PCSM) seeks to ensure the highest possible probability of success at UPT. PCSM applies regression weights to a candidate's Air Force Officer Qualification Test (AFOQT) Pilot composite score, self-reported flying hours, and five Basic Attributes Test (BAT) score composites. PCSM scores range between 0 and 99 and is interpreted as a candidate's probability of passing UPT. The goal of this study is to apply multivariate data analysis techniques to validate PCSM and determine appropriate changes to the model's weights. Performance of the updated weights is compared to the current PCSM model via Receiver Operating Curves …

Go to article

Analysis Of Organizational Architectures For The Air Force Tuition Assistance Program, Krista Z. Lapietra Mar 2003

Analysis Of Organizational Architectures For The Air Force Tuition Assistance Program, Krista Z. Lapietra

Theses and Dissertations

The consideration of restructuring through a change in organizational architecture is often a fiercely debated issue within an organization. The argument for restructuring to improve quality, customer service, and financial management is pitted against perceived lack of job security and historically poor results from previous restructuring initiatives. To balance all sides when considering a change in organizational architecture, the organization should use a method of evaluating potential architectures that assists in determining the best new architecture and generates support from those involved. The objective of this research is to provide the Air Force Education Division with a defendable methodology for …

Go to article

Air Force Reserve Force Structure Policy Evaluation Model, Scott A. Percival Mar 2003

Air Force Reserve Force Structure Policy Evaluation Model, Scott A. Percival

Theses and Dissertations

The United States Air Force Reserve is a constantly changing force. In response to these changes, the Active Guard Reserve (AGR), a small organization within the Reserve, is seeking to create a career track for Unit and Headquarters' Officers. It is necessary for the AGR policy division to be able to evaluate the availability of career paths to accomplish this goal. The Air Force Reserve Force Structure Evaluation Model provides the AGR management with a tool to aid them in evaluating policy impact. This model allows the AGR management to identify the impact policy changes may have on the resulting …

Go to article

Game Theory And U-Boats In The Bay Of Biscay, Joseph C. Price Mar 2003

Game Theory And U-Boats In The Bay Of Biscay, Joseph C. Price

Theses and Dissertations

Analysis of a large combat campaign using game theory is difficult due to non- linearities and other soft factors which exist in a complex system. However, game theory can give decision makers insight into strategies and outcomes that can be utilized to maximize one's objective. Agent-based simulation provides the means to model complex systems with non-linearities, by allowing for interactions among independent "agents." This thesis investigates game-theoretic strategies in agent-based simulation, modeled after the Allied search for U-boats in the Bay of Biscay during World War II (WWII). It also looks into the effects of adaptation on strategies by comparison …

Go to article

A Simulation Based Comparative Analysis Of Alternatives For Tuition Assistance Organizational Structures, Tamiko L. Ritschel Mar 2003

A Simulation Based Comparative Analysis Of Alternatives For Tuition Assistance Organizational Structures, Tamiko L. Ritschel

Theses and Dissertations

The military services have experienced enormous downsizing efforts in the last decade. With these initiatives, organizations have had to derive innovative ways to meet their objectives with fewer resources. An organization's structure is an avenue to address these challenges within the atmosphere of a shrinking capital budget. Organizational structure changes can affect every aspect of the organization. Such an impact suggests proposals for drastic organizational changes must meet the rigors of a full analysis. The intent of this research is to provide a comprehensive analysis of centralization options for Air Force Tuition Assistance efforts. This thesis effort involves the development …

Go to article

A Stochastic Model For Joint Reception, Staging, Onward Movement, And Integration (Jrsoi), Nathan P. Sherman Mar 2003

A Stochastic Model For Joint Reception, Staging, Onward Movement, And Integration (Jrsoi), Nathan P. Sherman

Theses and Dissertations

A stochastic model for the performance evaluation of a key phase in the deployment process, namely Joint Reception, Staging, Onward Movement, and Integration (JRSOI) is presented. The process is modeled as an open, multi-class tandem queueing network wherein personnel and various classes of cargo are modeled as the flow entities and the stages of the process constitute individual queueing stations. Single and multiple-class models at both low and high resolutions are presented. No analytical stochastic model of this process currently exists in the literature or in practice. The model provides a quick look at key aggregate performance measures such as …

Go to article

Optimal Replacement Policies For Satellite Constellations, Bradley R. Sumter Mar 2003

Optimal Replacement Policies For Satellite Constellations, Bradley R. Sumter

Theses and Dissertations

This work considers the problem of finding optimal replacement policies that minimize the expected total cost of maintaining a satellite constellation. The problem is modeled using discrete-time Markov decision processes to determine the replacement policy by allowing the satellite constellation to be in one of a finite number of states at each decision epoch. The constellation stochastically transitions at each time step from one state to another as determined by a set of transition probabilities. At each decision epoch, a decision maker chooses an action from a set of allowable actions for the current system state. A cost associated with …

Go to article

Models For Sortie Generation With Autonomic Logistics, Nicholaus A. Yager Mar 2003

Models For Sortie Generation With Autonomic Logistics, Nicholaus A. Yager

Theses and Dissertations

The primary objective of this research is to investigate the impact of an autonomic logistics system (ALS) on the sortie generation process for an individual airbase. As in some prior studies of this process, the methodology used to model the sortie generation process is a queueing network containing fork-join nodes for concurrent maintenance activities. The sortie generation rate is commonly regarded as the primary performance measure of the sortie generation process. This measure coincides with the throughput and is used to compare two models: (1) pre-ALS operations and (2) ALS-enhanced airbase operations. Analysis of the models shows that the ALS …

Go to article

An Investigation Of The Effects Of Correlation In Sensor Fusion, Susan A. Storm Mar 2003

An Investigation Of The Effects Of Correlation In Sensor Fusion, Susan A. Storm

Theses and Dissertations

This thesis takes the first step towards the creation of a synthetic classifier fusion-testing environment. The effects of data correlation on three classifier fusion techniques were examined. The three fusion methods tested were the ISOC fusion method (Haspert, 2000), the ROC "Within" Fusion method (Oxley and Bauer, 2002) and the simple use of a Probabilistic Neural Network (PNN) as a fusion tool. Test situations were developed to allow the examination of various levels of correlation both between and within feature streams. The effects of training a fusion ensemble on a common dataset versus an independent data set were also contrasted. …

Go to article

Multimission Aircraft Design Study-Operational Scenarios, Nevin Coskuner Mar 2003

Multimission Aircraft Design Study-Operational Scenarios, Nevin Coskuner

Theses and Dissertations

In the most recent years, the Command, Control and Communications, Counter Measures, Intelligence, Surveillance and Reconnaissance (C3CMISR) aircrafts are used commonly in many NATO and UN Operations around the world. These aircrafts are AWACS, JSTARS, Rivet Joint, Compass Call and ABCCC. They provide close air support in the name of airborne surveillance, ground moving target surveillance, target reconnaissance, jamming, and command, control and communications issues in operational environments. Those aircrafts are tasked with a wide variety of missions than ever before in operational theaters and each one of them comprises a specific amount of cost and risk factors. As a …

Go to article

Cargo Aircraft Bombing System (Cabs), Gurler Ari Mar 2003

Cargo Aircraft Bombing System (Cabs), Gurler Ari

Theses and Dissertations

From the early days of aviation, bombs typically have been carried by either fighter or bomber aircraft in the inventory. On the other hand, more and more long-range, precision-guided missiles are being produced with ranges that vary from tens to hundreds of miles. With such missiles, targets can be destroyed without placing personnel and equipment into close proximity to the targets. The mass delivery of standoff weapons could be especially advantageous during the early phases of an air campaign. This study considers the use of cargo aircraft for carrying and launching bombs and missiles. It discusses many aspects of a …

Go to article

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 19, Number 5, March 2003, College Of Engineering And Computer Science, Wright State University Mar 2003

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 19, Number 5, March 2003, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

An eight page newsletter created by the Wright State University College of Engineering and Computer Science that addresses the current affairs of the college.

Go to article

Gibbs Dividing Surface And Helium Adsorption, Sasidhar Gumma, Orhan Talu Mar 2003

Gibbs Dividing Surface And Helium Adsorption, Sasidhar Gumma, Orhan Talu

Chemical & Biomedical Engineering Faculty Publications

All adsorption data is based on the definition of Gibbs dividing surface, which is a purely mathematical transformation. Adsorption measurements in microporous solids necessitate experimental determination of the dividing surface. An international protocol does not exist on how to perform this important measurement. Commonly, helium is assumed not to adsorb and used as a probe molecule for this measurement. Each experimentalist chooses an arbitrary set of conditions, often without even disclosing them, which adds to the confusion in adsorption literature. Here, a self-consistent method for the analysis of helium data is proposed which does not assume non-adsorbing helium …

Go to article

First Prev Next Last