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Air Force Institute of Technology

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Articles 2491 - 2520 of 5700

Full-Text Articles in Engineering

A Simulation Of The Ecss Help Desk With The Erlang A Model, Michael E. Chua Mar 2011

A Simulation Of The Ecss Help Desk With The Erlang A Model, Michael E. Chua

Theses and Dissertations

During steady states, the Level 1 help desk might expect about 500 to 600 calls per month. That is about 0.39 to 0.46 calls per user per month, which represents the workload once ECSS is established and most of the users have already received training for the system. The optimal level for this workload is about 12 agents to operate the entire 24 hour period. At this level, the Level 1 help desk would minimize the amount of customers that renege from the system to about 15 to 22 percent and still maintain acceptable utilization percentages of about 52% to …

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Tailoring The Statistical Experimental Design Process For Lvc Experiments, Casey L. Haase Mar 2011

Tailoring The Statistical Experimental Design Process For Lvc Experiments, Casey L. Haase

Theses and Dissertations

The use of Live, Virtual and Constructive (LVC) Simulation environments are increasingly being examined for potential analytical use particularly in test and evaluation. The LVC simulation environments provide a mechanism for conducting joint mission testing and system of systems testing when scale and resource limitations prevent the accumulation of the necessary density and diversity of assets required for these complex and comprehensive tests. The statistical experimental design process is re-examined for potential application to LVC experiments and several additional considerations are identified to augment the experimental design process for use with LVC. This augmented statistical experimental design process is demonstrated …

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Measure Of Effectiveness For Jstars Ground Moving Target Indicator: A Value Focused Thinking Approach, Gardner J. Joyner Mar 2011

Measure Of Effectiveness For Jstars Ground Moving Target Indicator: A Value Focused Thinking Approach, Gardner J. Joyner

Theses and Dissertations

As the nature of warfare has shifted from a conventional approach to more guerilla type warfare, intelligence has become more important than at any other time in the history of the United States Military. With the stochastic nature of intelligence gathering, it is almost impossible to know with any degree of certainty where and when the next piece of information that could possibly change the course of the battle or war will be obtained. US intelligence gathering assets have long been plagued with using useless measures of performance rather than measures of effectiveness to determine their worth. This research uses …

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A Methodology Using Simulation Results For Test And Evaluation, Jonathon S. Hosket Mar 2011

A Methodology Using Simulation Results For Test And Evaluation, Jonathon S. Hosket

Theses and Dissertations

Each year the Air Force spends billions of dollars on Test and Evaluation to ensure acquisition programs roll out the best possible products. In 1997, the National Research Council assembled to evaluate the overall procedure used in procuring various platforms with system planning, research, development and engineering (SPRDE) and program management (PM) processes. In their final report, they claimed that the full advantages of statistical practices, simulation, model-test-models, and incorporation of prior test information into current test practices have not been fully utilized. To examine one of the report's recommendations, this thesis defines and explores a methodology using simulation to …

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Contextual Detection Of Anomalies In Hyperspectral Images, Adam J. Messer Mar 2011

Contextual Detection Of Anomalies In Hyperspectral Images, Adam J. Messer

Theses and Dissertations

The majority of anomaly detectors in Hyperspectral Imaging use only the statistical aspects of the spectral readings in the image. These detectors fail to use the spatial context that is contained in the images. The use of this information can yield detectors that out perform their spatially myopic counterparts. To demonstrate this, we will use an independent component analysis based detector, autonomous global anomaly detector (AutoGAD), developed at AFIT augmented to account for the spatial context of the detected anomalies. Through the use of segmentation algorithms, the anomalies identified are formed into regions. The size and shape of these regions …

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Application Of Post Modern Portfolio Theory To Mitigate Risk In International Shipping, Michael R. Quashne Mar 2011

Application Of Post Modern Portfolio Theory To Mitigate Risk In International Shipping, Michael R. Quashne

Theses and Dissertations

This research uses asset allocation concepts to determine the correct amount of cargo to send down the PAKGLOC and NDN to minimize the risk of loss or damage. Loss and Damage data is used from Transportation Discrepancy Reports and overall value is assumed to match the industry standard. Using assumed levels of pilferage along the NDN, a Monte Carlo simulation is run at each level of pilferage, and a Co-Lower Partial Moment model is solved. Analysis of the data shows a wide spread of possible optimal solutions at each level of pilferage. Due to the low levels of risk along …

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Weighted Key Player Problem For Social Network Analysis, Ryan M. Mcguire Mar 2011

Weighted Key Player Problem For Social Network Analysis, Ryan M. Mcguire

Theses and Dissertations

Social network analysis is a tool set whose uses range from measuring the impact of marketing campaigns to disrupting clandestine terrorist organizations. Social network analysis tools are primarily focused on the structure of relationships between actors in the network. However, characteristics of the actors, such as importance or status, are generally the output of the social network analysis rather than an input. Characteristics of actors can come from a number of sources to include information gathering, subject matter experts or social network analysis. Further, the strength of relationships between actors in social networks are often assumed to be all equal. …

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Depot-Level Simulation And Multivariate Analysis On B-1 High Velocity Maintenance, Florence K. Yee Mar 2011

Depot-Level Simulation And Multivariate Analysis On B-1 High Velocity Maintenance, Florence K. Yee

Theses and Dissertations

The objective of this thesis is to gain insights on the B-1B depot maintenance operations, with a focus on direct maintenance hours or burn rate, under the implementation of High Velocity Maintenance (HVM). Based on historical depot maintenance data and the current B-1 depot HVM prototype data, a discrete-event simulation model is developed using Arena 12.0. Some United States Air Force supply chain influences, such as manning levels and kitting characteristics of the B-1 depot operations, are incorporated in our models as design factors. The model captures the stochastic nature of 30 HVM tasks performed on one B-1 aircraft in …

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Empirical Characterization Of Ballistic Impact Flash, Thomas P. Talafuse Mar 2011

Empirical Characterization Of Ballistic Impact Flash, Thomas P. Talafuse

Theses and Dissertations

Fires onboard aircraft are leading mechanisms for mishaps and losses during peacetime and combat operations. Typical ignition sources causing fires onboard aircraft include electrical sparks and hot surfaces. However, impact and penetration of common threats encountered during combat operations, such as armor piercing incendiary projectiles and missile fragments, generate short-lived, but thermally-intense clouds (flashes) capable of igniting fires. Fire simulations supporting system-level survivability analyses depend on accurate characterization of these flash clouds, however, such accurate representations are not currently available. This research presents the modeling approach developed to estimate the boundary model representations of impact flashes. The research presents generalized …

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Characterization And In Vitro Toxicity Of Copper Nanoparticles (Cu-Nps) In Murine Neuroblastoma (N2a) Cells, Sitao Veronica Brownheim Mar 2011

Characterization And In Vitro Toxicity Of Copper Nanoparticles (Cu-Nps) In Murine Neuroblastoma (N2a) Cells, Sitao Veronica Brownheim

Theses and Dissertations

Nanomaterials, classified as materials within the 1 - 100 nanometer range, have seemingly endless applications. It is very important to the Air Force to increase the understanding of Cu-NPs and the possible health impacts from nanomaterial exposure prior to wide-spread industry and military use. Therefore, the purpose of this research is to thoroughly characterize the properties of three different copper samples upon suspension into aqueous solutions over time: Cu-NPs (Cu 25 nm), CuO-NPs (CuO 40 nm), and Cu-MSP (Cu 500nm). Additionally, this research seeks to observe in vitro effects upon murine neuroblastoma cells (N2A) by these three types of particles …

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Migration Issues In The Democratic Republic Of Congo, Michael J. Thompson Mar 2011

Migration Issues In The Democratic Republic Of Congo, Michael J. Thompson

Theses and Dissertations

Since the end of the Cold War, the number of weak and failing states has increased significantly. The United States (US) military has been deployed in multiple nation states in an effort to prevent these weak states from collapsing into chaos. This thesis explores one of the driving factors of state collapse, net migration, to gauge how US foreign policy might be employed to reduce the flow of people out of a country. To demonstrate the foreign policies and their effects, a pilot model was constructed using a system dynamics methodology. The Democratic Republic of Congo (DRC) was selected as …

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A Century Long Pursuit Of Alternative Fuels And Feedstocks: A Content Analysis, Elias J. Halvorson Mar 2011

A Century Long Pursuit Of Alternative Fuels And Feedstocks: A Content Analysis, Elias J. Halvorson

Theses and Dissertations

he United States has dramatically increased its production of alternative fuels over the past seven years. With the passing of the Energy Independence and Security Act of 2007 (EISA), alternative fuel production will increase in the United States over 700% from 2005 levels. However, the pursuit of petroleum alternatives is not a recent trend. Over the last 100 years, various nations have pursued petroleum alternatives with varying levels of success. This research focuses on the historical development of 10 leading alternative fuels and feedstocks. Through a thorough literature review we will identify commonalities among these fuels and feedstocks which have …

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Application Of Relational Contracting Methods To Federal Construction Projects, Travis R. Johnson Mar 2011

Application Of Relational Contracting Methods To Federal Construction Projects, Travis R. Johnson

Theses and Dissertations

Relational contracting is a method designed to improve relationships between contracted parties. The federal construction sector was a leader in the development and implementation of an early form of relational contracting known as partnering. Since then, alliancing has emerged as the new evolution of relational contracts. While it provides many potential benefits to contracting parties, alliancing has not yet been utilized in federal construction procurement, which is subject to stringent regulations. A commercially available standard form alliancing contract was selected for analysis against the Federal Acquisition Regulation. Key practices that characterize the alliancing method were identified. Utilizing a panel of …

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Modeling Enhanced Storage Of Groundwater Contaminants Due To The Presence Of Cracks In Low Permeability Zones Underlying Contaminant Source Areas, Jeremy M. Miniter Mar 2011

Modeling Enhanced Storage Of Groundwater Contaminants Due To The Presence Of Cracks In Low Permeability Zones Underlying Contaminant Source Areas, Jeremy M. Miniter

Theses and Dissertations

Throughout DoD, chlorinated aliphatic hydrocarbons (CAHs), a type of Dense Non-Aqueous Phase Liquid (DNAPL), have been frequently used. In the subsurface, spilled DNAPLs may pool atop low permeability clay layers. In this study a numerical model is constructed using the Groundwater Modeling System to assess how cracks in the clay, either pre-existing or the result of DNAPL-clay interactions, might impact a dissolved CAH plume generated by the DNAPL source. The conceptual model posits a DNAPL source in a high permeability sand aquifer sitting atop a low permeability clay layer. The model assumes dissolved CAH generated by the DNAPL is transported …

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Composite Aircraft Life Cycle Cost Estimating Model, Daniel B. Lambert Mar 2011

Composite Aircraft Life Cycle Cost Estimating Model, Daniel B. Lambert

Theses and Dissertations

Composite materials are beginning to comprise a greater percentage of structural materials used throughout aircraft production. The increased usage of composites has led individuals within the Air Force community to revisit aircraft life cycle cost, LCC, models. A series of affordability initiatives has culminated in significant evidence over the last decade to better quantify the impact of primarily composite structures in aircraft. The Advanced Composite Cargo Aircraft, ACCA, a research effort sponsored by the Air Force Research Lab, attempted to determine the impact of part size and large scale composite components on LCC for cargo aircraft. This research evaluates the …

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Retrospective Geospatial Modeling Of Pm10 Exposures From Open Burning At Joint Base Balad, Iraq, John P. Rinker Mar 2011

Retrospective Geospatial Modeling Of Pm10 Exposures From Open Burning At Joint Base Balad, Iraq, John P. Rinker

Theses and Dissertations

Predicting, determining, and linking theater-related source-specific exposures to health effects has proven difficult. The purpose of this research is to delineate retrospective exposure zones using spatially interpolated particulate air sampling point data from Joint Base Balad, create burn pit exposure isopleths from dispersion model outputs, and merge into a combined exposure model in GIS. Interpolated monitoring results and dispersion modeled results were combined to compare modeled exposures across base. Burn pit contribution to total PM10 was also modeled. The combined dispersion and interpolation map showed elevated concentrations within a 1 kilometer buffer of the burn pit. Buildings within this area …

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Characterization Of Graphite Composite Material Particulates From Usaf Aircraft Maintenance Operations, Richard E. Yon Mar 2011

Characterization Of Graphite Composite Material Particulates From Usaf Aircraft Maintenance Operations, Richard E. Yon

Theses and Dissertations

Due to the benefits of their material properties, advanced composite materials (ACM) are increasingly being used as structural components on aircraft, especially within the United States Air Force. As a result, the potential exists for occupational exposures to structural maintenance employees while repairing and fabricating aircraft components. Two field studies were conducted for this thesis in order to characterize ACM aerosol size distribution, determine the feasibility of utilizing direct reading instruments (DRIs) in the field, and ensure workers are protected with adequate controls. In order to characterize exposure, traditional integrated air sampling and DRIs were positioned together near an ACM …

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Degradation Modeling Of Polyurea Pavement Markings, Jonathan D. Needham Mar 2011

Degradation Modeling Of Polyurea Pavement Markings, Jonathan D. Needham

Theses and Dissertations

Polyurea is a long life pavement marking material used for assets requiring long periods of uninterrupted accessibility. Knowing the performance characteristics of such markings is critical to asset management planning focused on maximizing marking material life-cycles. This paper presents the performance characteristics of polyurea pavement markings in North Carolina using linear regression models. The models generated by this research provide pavement marking managers with tools to better allocate limited manpower and resources in order to optimize budgets while meeting newly proposed pavement marking retroreflectivity levels of service as proposed by the Federal Highway Administration. This research constructed performance models for …

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Application And Validation Of Concept Maturity Assessment Framework, Mathews C. Scharch, Jeremy J. Homan Mar 2011

Application And Validation Of Concept Maturity Assessment Framework, Mathews C. Scharch, Jeremy J. Homan

Theses and Dissertations

Far too often decision makers select concepts based on insufficient data, resulting in projects that are over-budget, over-schedule, and not what the customer wants. Research efforts have proposed a stage-gated concept maturity framework as a tool to assess and increase the maturity of concepts. This research uses multiple validation techniques to demonstrate the value this framework can provide. Interviews with acquisition professionals capture qualitative and quantitative data on the utility of the elements of the framework and the acquisition process. This research also applies the framework to a current acquisition program to determine if it can be broadly applied for …

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Spear Phishing Attack Detection, David T. Merritt Mar 2011

Spear Phishing Attack Detection, David T. Merritt

Theses and Dissertations

This thesis addresses the problem of identifying email spear phishing attacks, which are indicative of cyber espionage. Spear phishing consists of targeted emails sent to entice a victim to open a malicious file attachment or click on a malicious link that leads to a compromise of their computer. Current detection methods fail to detect emails of this kind consistently. The SPEar phishing Attack Detection system (SPEAD) is developed to analyze all incoming emails on a network for the presence of spear phishing attacks. SPEAD analyzes the following file types: Windows Portable Executable and Common Object File Format (PE/COFF), Adobe Reader, …

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A Simple Non-Destructive Method For Characterizing Non-Dispersive, Low-Loss Dielectrics, Thomas S. Olney Mar 2011

A Simple Non-Destructive Method For Characterizing Non-Dispersive, Low-Loss Dielectrics, Thomas S. Olney

Theses and Dissertations

It is shown how permittivity can be extracted via time domain reflection data from a perfect electric conductor (PEC) backed planar sample of a low-loss, non-dispersive dielectric using two rectangular Ku-band waveguide aperture probes with attached PEC flange plates of the same geometry but different dimensions. Of critical importance is being able to identify the reflection from the edge of the flange plate in the parallel plate region created by the plate and the PEC backing of the sample. A signal processing method that takes advantage of physical insight into the geometry and superposition is developed for identifying this edge …

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Multi Criteria Decision Support Model For The Turkish Air Force Personnel Course/Education Planning System, Cem Malyemez Mar 2011

Multi Criteria Decision Support Model For The Turkish Air Force Personnel Course/Education Planning System, Cem Malyemez

Theses and Dissertations

Many personnel are assigned to different courses and educational opportunities in the Turkish Air Force every year. This daunting process requires a great deal of time and does not currently seek to find an optimal solution. The Turkish Air Force has a database for all personnel information, but the officials use just a few quantitative personnel data points to complete their tasks. Moreover, the matching process is done by hand. Therefore there is a need for a model, which supports the Decision Makers, to cover the some of the other quantitative data points and also add some qualitative data for …

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Characterization Of Noise Technology Radar Signal Detectability Using A Non-Cooperative Receiver, Daniel V. Atienza Mar 2011

Characterization Of Noise Technology Radar Signal Detectability Using A Non-Cooperative Receiver, Daniel V. Atienza

Theses and Dissertations

As Noise Technology Radar (NTR) systems emerge, there is a need for non-cooperative, non-matched filter detection and exploitation. This work is based on that need and AFIT's Noise Network (NoNET) radar system. These signals are associated with Low Probability of Detection/ Intercept (LPD/LPI) signals. Quadrature Mirror Filter Banks (QMFB) has been effectively used for non-cooperatively detecting structured LPD/LPI signals and extracting various waveform characteristics. However, the QMFB process performance with unstructured NTR signals was challenging and motivated a need for a transformed QMFB. This transform was based on AFIT research by Gronholz and Mims (G-M), who used a multi-channel receiver …

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Improving The Relevance Of Cyber Incident Notification For Mission Assurance, Stephen M. Woskov Mar 2011

Improving The Relevance Of Cyber Incident Notification For Mission Assurance, Stephen M. Woskov

Theses and Dissertations

Military organizations have embedded Information and Communication Technology (ICT) into their core mission processes as a means to increase operational efficiency, improve decision making quality, and shorten the kill chain. This dependence can place the mission at risk when the loss, corruption, or degradation of the confidentiality, integrity, and/or availability of a critical information resource occurs. Since the accuracy, conciseness, and timeliness of the information used in decision making processes dramatically impacts the quality of command decisions, and hence, the operational mission outcome; the recognition, quantification, and documentation of critical mission-information resource dependencies is essential for the organization to gain …

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An Investigation Of Cavity Resonance And Its Relationship To Store Force And Moment Loading, Christopher J. Coley Mar 2011

An Investigation Of Cavity Resonance And Its Relationship To Store Force And Moment Loading, Christopher J. Coley

Theses and Dissertations

A store which is released from an internal bay is subjected to a highly unsteady flowfield which influences the release characteristics for the store. Pressure transducer information is often used to estimate store loading, although no direct correlation between the observed frequencies from the pressure transducers and the store loading has been developed. The relationship between the acoustic modes present in the cavity and the force and moment loading on a store released from a bay are investigated through a CFD study using the OVERFLOW 2.1 solver. The acoustic modes of the cavity are calculated from the pressure fluctuation histories …

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Flapping Wing Micro Air Vehicle Wing Manufacture And Force Testing, Nathanael J. Sladek Mar 2011

Flapping Wing Micro Air Vehicle Wing Manufacture And Force Testing, Nathanael J. Sladek

Theses and Dissertations

Numerous wing manufacturing techniques have been developed by various universities for research on Flapping Wing Micro Air Vehicles. Minimal attention though is given to repeatability of wing aerodynamics and dynamic response, which is crucial to avoid asymmetric flapping. Thus the focus of this research becomes twofold. First, repeatable wing manufacturing techniques are developed to ensure flapping wings have similar aerodynamic and dynamic characteristics. For this purpose, four wing designs were selected to not only test the aerodynamics of the different designs, but to also validate manufacturing techniques. The various wing designs are assessed using two methods: dynamic and aerodynamic data. …

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Perimeter Security And Intruder Detection Using Gravity Gradiometry: A Feasibility Study, Jared D. Tuinstra Mar 2011

Perimeter Security And Intruder Detection Using Gravity Gradiometry: A Feasibility Study, Jared D. Tuinstra

Theses and Dissertations

Changes in the mass distribution around some point on the Earth’s surface induce corresponding changes to the magnitude and direction of the gravity vector at that location. The nine-tensor derivative of the gravity vector, or gravity gradient, is sensitive to very small changes in the gravity vector. With some assumptions, continuous measurement of the gravity gradient using a gravity gradiometer (GGI) is used to determine the location of a mass change in the local area near the instrument. This investigation sought to determine the effectiveness, operating characteristics, and limitations of a physical perimeter security system that uses an array of …

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Software And Critical Technology Protection Against Side Channel Analysis Through Dynamic Hardware Obfuscation, John R. Bochert Mar 2011

Software And Critical Technology Protection Against Side Channel Analysis Through Dynamic Hardware Obfuscation, John R. Bochert

Theses and Dissertations

Side Channel Analysis (SCA) is a method by which an adversary can gather information about a processor by examining the activity being done on a microchip though the environment surrounding the chip. Side Channel Analysis attacks use SCA to attack a microcontroller when it is processing cryptographic code, and can allow an attacker to gain secret information, like a crypto-algorithm's key. The purpose of this thesis is to test proposed dynamic hardware methods to increase the hardware security of a microprocessor such that the software code being run on the microprocessor can be made more secure without having to change …

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Biological Investigation Of The Stimulated Flapping Motions Of The Moth, Manduca Sexta, Travis B. Tubbs Mar 2011

Biological Investigation Of The Stimulated Flapping Motions Of The Moth, Manduca Sexta, Travis B. Tubbs

Theses and Dissertations

No abstract provided.

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Creating A Network Model For The Integration Of Dynamic And Static Supervisory Control And Data Acquisition (Scada) Test Environment, Marlon Coerbell Mar 2011

Creating A Network Model For The Integration Of Dynamic And Static Supervisory Control And Data Acquisition (Scada) Test Environment, Marlon Coerbell

Theses and Dissertations

Since 9/11 protecting our critical infrastructure has become a national priority. Presidential Decision Directive 63 mandates and lays a foundation for ensuring all aspects of our nation's critical infrastructure remain secure. Key in this debate is the fact that much of our electrical power grid fails to meet the spirit of this requirement. My research leverages the power afforded by Electric Power and Communication Synchronizing Simulator (EPOCHS) developed with the assistance of Dr. Hopkinson, et al. The power environment is modeled in an electrical simulation environment called PowerWorld©. The network is modeled in OPNET® and populated with self-similar network and …

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