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Air Force Institute of Technology

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Surface Oxidation Study Of Uranium Dioxide Under Wet And Dry Conditions, Gary T. Brett Mar 2005

Surface Oxidation Study Of Uranium Dioxide Under Wet And Dry Conditions, Gary T. Brett

Theses and Dissertations

The surface oxidation of pressed uranium dioxide (UO2) powder under controlled environmental conditions and the oxidation and reduction of pressed uranium trioxide (UO3) powder are presented. This is a continuing research project in the investigation of the oxidation of UO2 powder using Photoluminescence (PL) Spectroscopy. UO2 particles exposed to the ambient atmosphere will oxidize into a number of chemical complexes (specifically hydrates, hydroxides, and carbonates). During certain of these oxidation processes, the uranium ion can lose two of its electrons and change from uranous (UIV+) to uranyl (UVI+). This research …

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Lethality Of Bacillus Anthracis Spores Due To Short Duration Heating Measured Using Infrared Spectroscopy, Kristina M. Goetz Mar 2005

Lethality Of Bacillus Anthracis Spores Due To Short Duration Heating Measured Using Infrared Spectroscopy, Kristina M. Goetz

Theses and Dissertations

There are a number of analytical and semi-empirical models that describe the behavior of particulate matter in the atmosphere. Many of these require modification for all types of weather, dry versus wet deposition, and overall effects can be quite non-linear. Rainfall (rate, drop size, etc.), snowfall (rate, flake size, etc.), humidity, pressure, temperature, and combination of these greatly affect particle settling and washout rates. To that end, a method for tracking released constituents using the Regional Atmospheric Modeling System (RAMS) microphysics package is developed by modifying one of the hydrometeor categories (hail) in the microphysics package. The RAMS microphysics package …

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Development Of 2-Dimensional Cloud Rise Model To Analyze Initial Nuclear Cloud Rise, Karson A. Sandman Mar 2005

Development Of 2-Dimensional Cloud Rise Model To Analyze Initial Nuclear Cloud Rise, Karson A. Sandman

Theses and Dissertations

The objective of this research is to create a two-dimensional cloud rise model that could be used instead of the current one-dimensional cloud rise model in the Defense Land Fallout Intepretive Code (DELFIC) option of the Hazard Prediction and Assessment Capability (HPAC). The model includes numerical analysis of partial differential equations involving pressure, potential temperature, horizontal and vertical winds, and specific humidity. The 2-D model developed provides a much more detailed definition of the physical properties within the mushroom cloud than the 1-D DELFIC option. This is particularly useful in fallout studies on particle formation, fractionation, and particle location within …

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A Comparison Of The Heft Subsurface And Delfic Particle Size Distributions And Effects In Hpac, Eric T. Skaar Mar 2005

A Comparison Of The Heft Subsurface And Delfic Particle Size Distributions And Effects In Hpac, Eric T. Skaar

Theses and Dissertations

The Heft subsurface three component lognormal fallout particle size distribution is compared and contrasted with the single lognormal fallout particle size distribution used by the Defense Land Fallout Interpretive Code (DELFIC). Comparison of the two distributions is accomplished with results from the AFIT smear code and the Hazard Prediction and Assessment Capability (HPAC). The effect of the distributions is explored in HPAC for varying yield weapons, varying surfaces, precipitation conditions, varying wind effects and varying dose rate times. The results from the two distributions are quantitatively compared using the concepts of grounded source normalization constant and the rate at which …

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Using Value-Focused Thinking To Evaluate The Practicality Of Ground-Source Heat Pumps At Military Installations, Jimmy J. Jeoun Mar 2005

Using Value-Focused Thinking To Evaluate The Practicality Of Ground-Source Heat Pumps At Military Installations, Jimmy J. Jeoun

Theses and Dissertations

Because of potential cost and energy savings, military decision-makers may want to consider the use of energy-efficient heating, ventilating, and air-conditioning (HVAC) systems at their installations. Ground source heat pumps (GSHPs), in particular, show great promise because of their low energy requirements and low life-cycle costs. However, there currently exists no design guidance or established criteria for HVAC selection. Consequently, military decision-makers have no basis for comparing conventional HVAC systems and GSHPs. The Value-Focused Thinking (VFT) methodology was used to create a multi-objective decision analysis model that measures the value of different HVAC systems. Consisting of five bottom-tier values and …

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Pick-Up And Delivery: A Comparison Of Functional Alignments And The Impact On Customer Service And Vehicle Operator Utilization, Shawn K. Booher Mar 2005

Pick-Up And Delivery: A Comparison Of Functional Alignments And The Impact On Customer Service And Vehicle Operator Utilization, Shawn K. Booher

Theses and Dissertations

The Chief of Staff Logistics Review of 1999 examined a multitude of process issues and their resulting impact on organizational structure. A resulting initiative was to transition the pick-up and delivery function from the Material Management flight (LGRM) to the Vehicle Operations section (LGRVO). The motivation of this initiative, more specifically referred to as Supply/Transportation Reengineering, was to streamline similar processes, and to effectively and efficiently utilize resources. The goal of this transition was to use fewer people and resources to provide pick-up and delivery service to wing customers with minimal adverse impact to customer service and to improve overall …

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Minimizing Security Forces Response Times Through The Use Of Facility Location Methodologies, Michael C. Dawson Mar 2005

Minimizing Security Forces Response Times Through The Use Of Facility Location Methodologies, Michael C. Dawson

Theses and Dissertations

Since the events of September 11, 2001, security for the nation's Intercontinental Ballistic Missile force has become a prominent concern for personnel in the highest levels of government. This has resulted in many physical security upgrades and new methods to counter hostile activities. This research seeks to find the optimal placement for one layer of the security net protecting these crucial assets, the daily-deployed security forces Fire Teams. The problem of finding the optimal placement for these forces is modeled as a facility location problem. Three of the methods of locating facilities available in the literature are selected to solve …

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Analysis Of Online-Delaunay Navigation For Time Sensitive Targeting, David Chow Mar 2005

Analysis Of Online-Delaunay Navigation For Time Sensitive Targeting, David Chow

Theses and Dissertations

Given the drawbacks of leaving time-sensitive targeting (TST) strictly to humans, there is value to the investigation of alternative approaches to TST operations that employ autonomous systems. This paper accomplishes five things. First, it proposes a short-hop abbreviated routing paradigm (SHARP) - based on Delaunay triangulations (DT), ad-hoc communication, and autonomous control - for recognizing and engaging TSTs that, in theory, will improve upon persistence, the volume of influence, autonomy, range, and situational awareness. Second, it analyzes the minimum timeframe need by a strike (weapons enabled) aircraft to navigate to the location of a TST under SHARP. Third, it shows …

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Optimal Maintenance For Stochastically Degrading Satellite Constellations, Timothy J. Cook Mar 2005

Optimal Maintenance For Stochastically Degrading Satellite Constellations, Timothy J. Cook

Theses and Dissertations

This thesis develops a methodology to determine an optimal policy for maintaining a satellite constellation that degrades over time. Previous work has developed a methodology to compute an optimal replacement policy for a satellite constellation in which satellites were viewed as binary entities, either operational or failed. This research extends the previous models by developing an optimal maintenance policy for satellite constellations in which each satellite may operate in a finite number of degraded states. The constellation is assumed to consist of a finite number of satellites, each with a finite number of functions with distinct failure mechanisms. Assuming each …

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On The Use Of Surrogate Functions For Mixed Variable Optimization Of Simulated Systems, John E. Dunlap Mar 2005

On The Use Of Surrogate Functions For Mixed Variable Optimization Of Simulated Systems, John E. Dunlap

Theses and Dissertations

This research considers the efficient numerical solution of linearly constrained mixed variable programming (MVP) problems, in which the objective function is a black-box stochastic simulation, function evaluations may be computationally expensive, and derivative information is typically not available. MVP problems are those with a mixture of continuous, integer, and categorical variables, the latter of which may take on values only from a predefined list and may even be non-numeric. Mixed Variable Generalized Pattern Search with Ranking and Selection (MGPS-RS) is the only existing, provably convergent algorithm that can be applied to this class of problems. Present in this algorithm is …

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Modeling And Analysis Of Clandestine Networks, Clinton R. Clark Mar 2005

Modeling And Analysis Of Clandestine Networks, Clinton R. Clark

Theses and Dissertations

Since Sept. 11, 2001, there has been great interest in the military and intelligence communities in using Social Network Analysis (SNA) to support the disruption and destruction of global terrorist networks. SNA results, however, tend to be descriptive and are limited due to the lack of advantageous properties of the relationship measures applied to the arcs in a social network. Further, SNA techniques generally focus on a single network context while real relationships are based in multiple contexts. This thesis develops a new proxy measure of pair-wise potential influence between members of a network, a Holistic Interpersonal Influence Measure (HIIM). …

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Stochastic Capability Models For Degrading Satellite Constellations, Cole W. Gulyas Mar 2005

Stochastic Capability Models For Degrading Satellite Constellations, Cole W. Gulyas

Theses and Dissertations

This thesis proposes and analyzes a new measure of functional capability for satellite constellations that incorporates the instantaneous availability and mission effectiveness of individual satellites. The capability measure yields a continuous score between zero and one accounting for the degree to which the constellation meets operational requirements. The measure is computed from an average of satellite capabilities, composed of the product of the satellite's instantaneous availability and value score. Instantaneous availability is acquired by modeling the satellite degradation status as either a time-homogenous, continuous-time Markov chain (CTMC) if it possesses functions with exponential lifetime distributions, or as a time-homogenous, semi-Markov …

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Modeling Transnational Terrorists' Center Of Gravity: An Elements Of Influence Approach, Cheryl L. Hetherington Mar 2005

Modeling Transnational Terrorists' Center Of Gravity: An Elements Of Influence Approach, Cheryl L. Hetherington

Theses and Dissertations

Since the September 11th terrorist attack, there has been an increased emphasis on understanding and modeling terrorists groups. While several efforts have focused on identifying transnational terrorists' centers of gravity (COGs), most of these efforts have proposed COGs using a traditional nation-state paradigm. In today's "global village", terrorist groups are no longer limited by locality and national boundaries. With the increasing threats from transnational terrorist groups, new paradigms and models are necessary to properly analyze today's, and tomorrow's, conflict. Analysis should be based on the identified and quantified transnational terrorists' COGs and their associated interactions. Unfortunately, not all of the …

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An Investigation Of The Effects Of Correlation And Autocorrelation In Classifier Fusion With Non-Declarations, Frank M. Mindrup Mar 2005

An Investigation Of The Effects Of Correlation And Autocorrelation In Classifier Fusion With Non-Declarations, Frank M. Mindrup

Theses and Dissertations

Air Force doctrine requires reliable and accurate information when striking targets. Further, this doctrine states that fusion should be utilized whenever possible to ensure the best possible information is conveyed; there is no specific guidance as to how to fuse this information. This thesis extends the research found in Leap, Bauer, and Oxley (2004) to include a non-declared class. The Identification system operating characteristic (ISOC) was adapted to allow for non-declarations both at the individual sensor level as well as the fused output level. A probabilistic neural network (PNN) was also used as a fusion technique. A cost function was …

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A Capacitated Facility Location Approach For The Tanker Employment Problem, Jeffrey R. Miller Mar 2005

A Capacitated Facility Location Approach For The Tanker Employment Problem, Jeffrey R. Miller

Theses and Dissertations

Air refueling is conducted to provide rapid response, increased range, and extended airborne operations for bombers, fighters, airlift, command and control, and intelligence, surveillance, and reconnaissance aircraft. The planning and scheduling of limited tanker resources during employment operations is a major concern for Air Mobility Command (AMC). AMC does not currently have a simple tool that runs in a short amount of time to aid in planning operations. The tool developed allows AMC to input several sorties consisting of various aircraft types and armaments. Each sortie contains a base of origin, and is assumed to be attacking or patrolling in …

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Selection And Application Of Distorted Risk Measures, Edwin J. Offutt Mar 2005

Selection And Application Of Distorted Risk Measures, Edwin J. Offutt

Theses and Dissertations

This thesis develops and illustrates a methodology for the selection of probability distributions and distortion functions associated with risk scenarios resulting from military capability shortfalls. Distorted (or transformed) risk measures are analyzed and applied to account for loss scenarios that may occur with low frequency but result in catastrophic outcomes. After reviewing the rudimentary concepts of distortion, four well-known continuous distributions, suitable for modeling risk scenarios, are chosen using defined criteria. Based on subject matter expert inputs, a simple method for assigning exactly one of the four distributions to any risk scenario is proposed. Four parametric distortion functions from the …

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Optimal Sampling Of A Chemical Hazard Area, Jennifer R. Plourde Mar 2005

Optimal Sampling Of A Chemical Hazard Area, Jennifer R. Plourde

Theses and Dissertations

This thesis proposes a methodology for optimally sampling a chemical hazard area subsequent to a chemical weapons attack. The objective is to identify the maximum number of areas that no longer require protective gear for safe operations. We model the area as an undirected graph and employ network analysis techniques to provide a methodological framework for identifying an optimal sampling sequence within a fixed time limit. We propose four models that characterize the secondary vapor concentrations: i) static and deterministic, ii) static and stochastic, iii) dynamic and deterministic, and iv) dynamic and stochastic. Comparisons of the static cases and their …

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Strategic Airlift En Route Analysis And Considerations To Support The Global War On Terrorism, Michael C. Sere Mar 2005

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 …

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Informal Influences In The Process Of Idiq Contractor Selection For Task Award, Jason E. Blevins Mar 2005

Informal Influences In The Process Of Idiq Contractor Selection For Task Award, Jason E. Blevins

Theses and Dissertations

The selection of a contractor for task award using the Indefinite Delivery Indefinite Quantity (IDIQ) contract often involves dynamics and relationships that are difficult to understand. There are unanswered questions that relate to how government agents define "best value" to the government. The selection decisions often differ between government agents. The government streamlined the acquisition process by creating the multiple award IDIQ contract. Government agents are relied upon to make sound business judgments in determining which contractor represents the best value to the government. Informal influences can impact the determination of the final selection of a contractor. This thesis attempts …

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Estimating Performance Time For Air Force Military Construction Projects, Greg J. Hoffman Mar 2005

Estimating Performance Time For Air Force Military Construction Projects, Greg J. Hoffman

Theses and Dissertations

The prediction of construction time performance is a problem of interest to both researchers and construction industry practitioners. This research seeks to identify significant factors which may influence construction durations for Air Force Military Construction (MILCON) projects to establish a time prediction model. Data were collected for 856 MILCON projects completed between 1988 and 2004; this included both traditional facility and non-facility (e.g. airfield pavements, utilities) projects. These data were analyzed using Bromilow's time-cost (BTC) model (1969) as well as multiple linear regression. Neither model produced acceptable results for non-facility projects; however, the multiple linear regression model was found to …

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Dynamic Modeling And Evaluation Of Recurring Infrastructure Maintenance Budget Determination Methods, Matthew P. Jefson Mar 2005

Dynamic Modeling And Evaluation Of Recurring Infrastructure Maintenance Budget Determination Methods, Matthew P. Jefson

Theses and Dissertations

The focus of this research is using system dynamics modeling to evaluate the impact of missed scheduled maintenance due to budgetary constraints. Missed maintenance cannot be made up and the benefit to the facility's serviceability is lost. The cumulative effect on an entire facility's life span is that it is unable to reach its designed life expectancy. Replacement construction costs are hundreds, thousands, or millions times more than the annual maintenance repair costs. Therefore, Air Force civil engineers must be capable of evaluating maintenance strategies in a dynamic environment to determine the budget strategy's prolonged effect on infrastructure serviceable life. …

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Modeling Application Of Hydrogen Release Compound To Effect In Situ Bioremediation Of Chlorinated Solvent-Contaminated Groundwater, Ryan C. Wood Mar 2005

Modeling Application Of Hydrogen Release Compound To Effect In Situ Bioremediation Of Chlorinated Solvent-Contaminated Groundwater, Ryan C. Wood

Theses and Dissertations

This study investigates how application of Hydrogen Release Compound (HRC) might be implemented to remediate a site contaminated with tetrachloroethene (PCE) or its daughter products, under varying site conditions. The 3-D reactive transport model RT3D was coupled with a dual-Monod biodegradation submodel to simulate the effect of the hydrogen generated by HRC on accelerating the biodegradation of dissolved chlorinated solvents. Varying site conditions and injection well configurations were investigated to determine the effect of these environmental and design conditions on overall treatment efficiency. The model was applied to data obtained at a chlorinated solvent contaminated site at Vandenberg AFB, where …

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An Analysis Of Information Assurance Relating To The Department Of Defense Radio Frequency Identification (Rfid) Passive Network, Robert G. Giovannetti Mar 2005

An Analysis Of Information Assurance Relating To The Department Of Defense Radio Frequency Identification (Rfid) Passive Network, Robert G. Giovannetti

Theses and Dissertations

The mandates for suppliers to commence Radio Frequency Identification tagging set by Wal-Mart and the Department of Defense is changing this long-time rumored technology into reality. Despite the many conveniences to automate and improve asset tracking this technology offers, consumer groups have obstinately opposed this adoption due to the perceived weaknesses in security and privacy of the network. While the heated debate between consumers and retailers continues, little to no research has addressed the implications of security on the Department of Defense Radio Frequency Identification network. This thesis utilized a historical analysis of Radio Frequency Identification literature to determine whether …

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The Analysis Of Air Force Institute Of Technology Theses Related To Contracting, Thomas M. Clohessy Mar 2005

The Analysis Of Air Force Institute Of Technology Theses Related To Contracting, Thomas M. Clohessy

Theses and Dissertations

At the end of March 2005, the final students will graduate from the Air Force Institute of Technology's (AFIT) contracting graduate degree curricula -- consisting at various times of both contract management and strategic purchasing course sequences -- which have been relocated to the Naval Postgraduate School (NPS). With the end of the contracting graduate programs at AFIT, it is appropriate to ask what contributions AFIT theses have made to the contracting community. Scholars (e.g., Das and Hanfield, 1997) have argued that thesis and dissertation research is one useful method of determining contributions to the field. The author conducted a …

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Performance Based Service Acquisition: A Quantitative Evaluation Of Implementation Goals And Performance In The United States Air Force, Dylan D. Pope Mar 2005

Performance Based Service Acquisition: A Quantitative Evaluation Of Implementation Goals And Performance In The United States Air Force, Dylan D. Pope

Theses and Dissertations

In an attempt to maximize cost savings in the rapidly growing services sector, the DoD established a Performance Based Service Acquisition (PBSA) strategy that focuses on evaluating contractor performance based on their ability to meet desired outcomes rather than the means to which the outcomes are obtained. In April 2000, Dr. Gansler, then Under Secretary of Defense for Acquisition, Technology and Logistics, mandated that 50 percent of all eligible service acquisitions be awarded using PBSA methods by FY 2005. Since then very little research has been focused on USAF implementation of PBSA and the progress and attainment of the PBSA …

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Daytime Detection Of Space Objects, Alistair D. Funge Mar 2005

Daytime Detection Of Space Objects, Alistair D. Funge

Theses and Dissertations

Space Situational Awareness (SSA) requires repeated object updates for orbit accuracy. Detection of unknown objects is critical. A daytime model was developed that evaluated sun flares and assessed thermal emissions from space objects. Iridium satellites generate predictable sun glints. These were used as a model baseline for daytime detections. Flares and space object thermal emissions were examined for daytime detection. A variety of geometric, material and atmospheric characteristics affected this daytime detection capability. In a photon noise limited mode, simulated Iridium flares were detected. The peak Signal-to- Noise Ratios (SNR) were 6.05e18, 9.63e5, and 1.65e7 for the nighttime, daytime and …

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Simple Public Key Infrastructure Analysis Protocol Analysis And Design, Alexander G. Vidergar Mar 2005

Simple Public Key Infrastructure Analysis Protocol Analysis And Design, Alexander G. Vidergar

Theses and Dissertations

Secure electronic communication is based on secrecy, authentication and authorization. One means of assuring a communication has these properties is to use Public Key Cryptography (PKC). The framework consisting of standards, protocols and instructions that make PKC usable in communication applications is called a Public Key Infrastructure (PKI). This thesis aims at proving the applicability of the Simple Public Key Infrastructure (SPKI) as a means of PKC. The strand space approach of Guttman and Thayer is used to provide an appropriate model for analysis. A Diffie-Hellman strand space model is combined with mixed strand space proof methods for proving the …

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Determination Of Structure From Motion Using Aerial Imagery, Paul R. Graham Mar 2005

Determination Of Structure From Motion Using Aerial Imagery, Paul R. Graham

Theses and Dissertations

The structure from motion process creates three-dimensional models from a sequence of images. Until recently, most research in this field has been restricted to land-based imagery. This research examines the current methods of land-based structure from motion and evaluates their performance for aerial imagery. Current structure from motion algorithms search the initial image for features to track though the subsequent images. These features are used to create point correspondences between the two images. The correspondences are used to estimate the motion of the camera and then the three-dimensional structure of the scene. This research tests current algorithms using synthetic data …

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Robot Mapping With Real-Time Incremental Localization Using Expectation Maximization, Kevin L. Owens Mar 2005

Robot Mapping With Real-Time Incremental Localization Using Expectation Maximization, Kevin L. Owens

Theses and Dissertations

This research effort explores and develops a real-time sonar-based robot mapping and localization algorithm that provides pose correction within the context of a single room, to be combined with pre-existing global localization techniques, and thus produce a single, well-formed map of an unknown environment. Our algorithm implements an expectation maximization algorithm that is based on the notion of the alpha-beta functions of a Hidden Markov Model. It performs a forward alpha calculation as an integral component of the occupancy grid mapping procedure using local maps in place of a single global map, and a backward beta calculation that considers the …

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Assessing Information Trustability In A Secure Web Services Environment, Charles G. Penner Mar 2005

Assessing Information Trustability In A Secure Web Services Environment, Charles G. Penner

Theses and Dissertations

Decisions are made based on available information. A decision support system endeavors to provide information that is timely, accurate, and trustable. Information gathered from secure web service transactions has attributes that can be used to assess a level of trustability. The trust assessments enable a decision maker to determine a basis for confidence in the information presented from the web service. Existing trust assessment models do not provide a way to determine from a particular trust assessment what information attributes contributed to its computation. The present work creates trust values that retain and denote meaning, allowing a decision maker to …

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