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2000

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Determining The Aircraft Requirement For Turkish Air Mobility System, Mehmet M. Ari Mar 2000

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 …

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Tool-Based Integration And Code Generation Of Object Models, Michael Ray Ashby Mar 2000

Tool-Based Integration And Code Generation Of Object Models, Michael Ray Ashby

Theses and Dissertations

Today many organizations are faced with multiple large legacy data stores in different formats and the need to use data from each data store with tools based on the other data stores' formats. This thesis presents a tool-based methodology for integrating object-oriented data models with automatic generation of code. The generated code defines a global data format, generates views of global data in individual integrated data formats, and parses data from individual formats to the global formats and from the global format to the individual formats. This allows for legacy data to be translated into the global format, and all …

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The Distributor’S Three-Dimensional Pallet-Packing Problem: A Mathematical Formulation And Heuristic Solution Approach, Brian P. Ballew Mar 2000

The Distributor’S Three-Dimensional Pallet-Packing Problem: A Mathematical Formulation And Heuristic Solution Approach, Brian P. Ballew

Theses and Dissertations

It is through practice and experience Air Force loadmasters are able to pack the Air Force standard HCU-6/E (463L) pallets efficiently. Although the loadmasters perform their jobs exceptionally well, the Air Force is in search of a model that will more efficiently pack the pallets. We have developed a mathematical formulation of the three-dimensional pallet-packing problem which minimizes the amount of unused space on a pallet. The formulation ensures each box is packed with the correct volume and dimensions, and ensures the volume of all the boxes packed is less than the available pallet volume. Additionally, the formulation ensures that …

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Locating Search And Rescue Stations In The Aegean And Western Mediterranean Regions Of Turkey, Melih M. Basdemir Mar 2000

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 …

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Robust Multi-Scenario Optimization Of An Air Expeditionary Force Force Structure Applying Genetic Algorithms To The Combat Forces Assessment Model, Barry D. Bennett Jr. Mar 2000

Robust Multi-Scenario Optimization Of An Air Expeditionary Force Force Structure Applying Genetic Algorithms To The Combat Forces Assessment Model, Barry D. Bennett Jr.

Theses and Dissertations

The United States Air Force is increasingly facing more diverse threat situations while existing force structure levels are being reduced and proposed compositions are being severely scrutinized for relevance, affordability, and effectiveness. Military planners are struggling with the question of how to generate a single force structure that can adequately respond to a multitude of threat scenarios in an uncertain future while at the same time being tasked to prove just how effective their choice will be. In the past, modeling has been effective in showing how a force can respond to a single threat scenario but a new modeling …

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Extracting Mission Semantics From Unmanned Aerial Vehicle Telemetry And Flight Plans, Walter T. Berridge Mar 2000

Extracting Mission Semantics From Unmanned Aerial Vehicle Telemetry And Flight Plans, Walter T. Berridge

Theses and Dissertations

With the acceptance of Unmanned Aerial Vehicles (UAVs) as a primary platform within the Department of Defense (DOD) for gathering intelligence data, the amount of video information being recorded, analyzed, and archived continues to grow. Mechanisms for quickly locating and retrieving video segments of interest amongst the many hours of recorded video are required to accommodate the rapid turnaround expected in today's wartime planning environments. This research demonstrates that text-based data accompanying UAV video yields sufficient information to identify and create data items that can be indexed to provide for rapid identification and retrieval of video segments of interest. Four …

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Finite Element Analysis Of A Composite Cylindrical Shell With A Cutout Under A Fatigue Load, Joshua T. Boatwright Mar 2000

Finite Element Analysis Of A Composite Cylindrical Shell With A Cutout Under A Fatigue Load, Joshua T. Boatwright

Theses and Dissertations

A higher-order shell theory is used to analyze compressive and tensile loads on a graphite/epoxy laminated cylinder containing a square cutout. The Hashin failure criterion is used to determine failure in the fiber, matrix, or lamination. Once failure occurs, the appropriate stiffness terms are reduced. This failure causes a redistribution of stress, leading to further failure. In order to account for the loss of residual strength due to cyclic loading, the stiffness matrix is further reduced at each new increment of load or displacement. The objective is not to determine the S-N curve for the material, but rather to determine …

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An Analysis In Cloud-To-Ground Lightning Over Land Versus Water, Elizabeth A. Boll Mar 2000

An Analysis In Cloud-To-Ground Lightning Over Land Versus Water, Elizabeth A. Boll

Theses and Dissertations

Understanding lightning characteristics over land and water is vital to achieving optimal safety and success in Air Force missions. Lightning safety rules are often based on experience rather than a scientific understanding of lightning. Examining lightning characteristics over water and land will assist in a better understanding of lightning and provide answers that can protect human lives and property. Water and land have different compositions and surface conductivity values. A lightning stroke is detected through a change in the electro-magnetic field at the surface. The change in surface conductivity values from land to water can affect the detection of a …

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Evaluation Of A Method For Kinematic Gps Carrier-Phase Ambiguity Resolution Using A Network Of Reference Receivers, Brian L. Bracy Mar 2000

Evaluation Of A Method For Kinematic Gps Carrier-Phase Ambiguity Resolution Using A Network Of Reference Receivers, Brian L. Bracy

Theses and Dissertations

New applications for GPS have driven a demand for increased positioning accuracy. The emerging GPS technology particularly affects the test community. The testing equipment and method must provide a solution that is an order of magnitude more precise than the tested equipment to achieve the desired accuracy. Carrier-phase differential GPS methods using a network of reference receivers can provide the centimeter-level accuracy required over a large geographical area. This thesis evaluates the performance of a 5-receiver network over a 50 km x 120 km area of New Mexico, using a GPS network algorithm called NetAdjust. The percentage of time a …

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Stochastic Modeling-Based Dgps Estimation Algorithm, James T. Broaddus Mar 2000

Stochastic Modeling-Based Dgps Estimation Algorithm, James T. Broaddus

Theses and Dissertations

A Kinematic Differential Global Positioning System (KDGPS) algorithm is developed. A number of mobile receivers is considered, one of which will be designated the reference station' which will have known position and velocity information at the beginning of the time interval examined. Satellite clock biases are used to model Selective Availability. The measurement situation on hand is properly modeled and a centralized estimation algorithm processing several epochs of data. The effect of uncertainty in the reference receiver's position and the level of receiver noise is examined. Monte Carlo simulations are performed to examine the ability of the algorithm to correctly …

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Using Rsm, Doe, And Linear Regression To Develop A Metamodel To Predict Cargo Delivery Of A Time Phase Force Deployment Document, Kenneth S. Browne Mar 2000

Using Rsm, Doe, And Linear Regression To Develop A Metamodel To Predict Cargo Delivery Of A Time Phase Force Deployment Document, Kenneth S. Browne

Theses and Dissertations

Air Mobility Command (AMC) uses the Airlift Flow Model as their primary tool to estimate the amount of cargo delivered in a Time Phase Force Deployment Document (TPFDD). The primary objective of this research was an exploratory investigation in the development of a metamodel to predict the amount of cargo delivered from a TPFDD by AMC into a theater. In creating a valid metamodel the analyst would be able to quickly provide the decision-maker with accurate insights should input parameters change. This would save valuable time and replace the need to physically change the input parameters and re-run the simulation. …

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Generating Executable Persistent Data Storage/Retrieval Code From Object-Oriented Specifications, Steven R. Buckwalter Mar 2000

Generating Executable Persistent Data Storage/Retrieval Code From Object-Oriented Specifications, Steven R. Buckwalter

Theses and Dissertations

This research creates a methodology and corresponding prototype for the transformation of object-oriented (OO) specifications to represent the corresponding relational schemas that are used to automatically generate database design language (DDL). The transformation design decisions and specifications are then used to generate database manipulation language (DML) that can be embedded within the software application code generated from the same OO specifications. This concept of developing a model for producing compilable and executable code from formal software specifications has long been a goal of software engineers. Previous research at the Air Force Institute of Technology (AFIT) has not focused on the …

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Hierarchical Interactive Theater Model (Hitm): An Investigation Into The Relationship Between Strategic Effects And Ooda Loops, Richard K. Bullock Mar 2000

Hierarchical Interactive Theater Model (Hitm): An Investigation Into The Relationship Between Strategic Effects And Ooda Loops, Richard K. Bullock

Theses and Dissertations

Airpower's strength lies in being able to quickly strike the enemy directly where they are vulnerable while being unhampered by geography and surface forces. Airpower theory suggests the effects of these strikes propagate throughout an opponent1s military system yielding catastrophic output or strategic effects. Despite this theory being a cornerstone of US Air Force doctrine, current Air Force models do not seem to capture airpower's inherent strength. Since these models are used to support budgetary decision making, the United States may not be funding the airpower capability it needs.

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A Decision Support Tool To Aid Campaign Planners In Selecting Combat Aircraft For Theater Crisis, Christopher D. Buzo Mar 2000

A Decision Support Tool To Aid Campaign Planners In Selecting Combat Aircraft For Theater Crisis, Christopher D. Buzo

Theses and Dissertations

One way of comparing alternative deployment plans is to examine how combat aircraft tasked within a deployment plan meet the combat commander's requirements. Both the absolute capabilities and the campaign-specific issues affecting the operational capabilities of those aircraft could assess a set of combat aircraft, unique to a deployment plan. This research-develops a non-absolute, campaign-specific decision Support tool to assess the effect of campaign-specific issues on a set of deployable Air Force combat aircraft. This research is conducted in three phases. Cognitive Task Analysis (CTA) and Multi-Attribute Preference Theory (MAPT) methodologies are applied to in-person and telephone interviews with subject …

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A Tabu Search For Scheduling And Rescheduling Combat Aircraft, Kevin M. Calhoun Mar 2000

A Tabu Search For Scheduling And Rescheduling Combat Aircraft, Kevin M. Calhoun

Theses and Dissertations

Scheduling an air campaign is time and labor intensive. Exacerbating the problem, combat planners use manual methods to accomplish much of this daunting but critical task. While some work has been done to automate the process, the approaches used generate schedules that must undergo major modifications before they are "flyable." Planners, therefore, distrust the results and use the automated features of the software sparingly. Additional problems arise due to the lag time between the publication of the Air Tasking Order (ATO) and the start of the ATO day. During this time, conditions change in the dynamic battlespace (aircraft break, runways …

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Extensible Markup Language As A Weather Tool, Michael J. Calidonna Mar 2000

Extensible Markup Language As A Weather Tool, Michael J. Calidonna

Theses and Dissertations

This thesis is a proof of concept work that will extend the Core Mapping Application Program Interface (CMAPI) components to include weather data. The CMAPI project is headed by Air Force Research Lab (AFRL)/Information Directorate Information Handling Branch (IFEB) at Rome labs in Rome, New York. This work extends the CMAPI project in two distinct areas. The first goal is to figure out how to overlay and display weather data on a dynamically linked Internet platform. This was accomplished by incorporating existing data from the Air Force Weather Agency (AFWA) into the CMAPI program in a static environment. The other …

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Investigation Of Laser Beam Combining And Cleanup Via Seeded Stimulated Brillouin Scattering In Multimode Optical Fibers, Bryan J. Choi Mar 2000

Investigation Of Laser Beam Combining And Cleanup Via Seeded Stimulated Brillouin Scattering In Multimode Optical Fibers, Bryan J. Choi

Theses and Dissertations

The purpose of this thesis research was to determine if stimulated Brillouin scattering amplification in multimode optical fibers would exhibit the same laser beam combining and clean-up properties exhibited by SBS oscillation, and to characterize the Brillouin amplification process in a multimode optical fiber. Beam combining in multimode fibers via SBS is being considered as a method of combining low power laser beams into a single beam having higher power and superior spatial coherence for applications such as electro-optic countermeasures. Experimental results demonstrate seeding a 9.5 mm fiber significantly reduced the pump power required to initiate SBS. An amplified Stokes …

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A Neural Network Solution To Predicting Wind Speed At Cape Canaveral’S Atlas Launch Pad, Kenneth P. Cloys Mar 2000

A Neural Network Solution To Predicting Wind Speed At Cape Canaveral’S Atlas Launch Pad, Kenneth P. Cloys

Theses and Dissertations

This thesis demonstrates the potential for using time-delay neural networks to provide Launch Weather Officers (LWOs) at 45th Weather Squadron (45 WS) with advance warning of wintertime (November-March) peak wind speeds at the Atlas launch pad. The 45 WS provides weather support to the United States space program at Cape Canaveral Air Station, NASA's Kennedy Space Center, and Patrick Air Force Base. Due to the complex wintertime environment produced by the effects of friction and instability, 45 WS LWOs consider wintertime launch pad winds their toughest forecast challenge. Neural networks were developed, trained, and tested using observations of wintertime peak …

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Use Of Climatology To Predict Maximum Wind Speeds At The Kennedy Space Center And Cape Canaveral Air Station, Lisa K. Coleman Mar 2000

Use Of Climatology To Predict Maximum Wind Speeds At The Kennedy Space Center And Cape Canaveral Air Station, Lisa K. Coleman

Theses and Dissertations

This thesis uses statistical analysis to forecast the probability of meeting or exceeding the maximum allowable wind speeds for each of the launch pads at the Kennedy Space Center (KSC) and Cape Canaveral Air Station (CCAS). Wind data were collected from the Weather Information Network Display System (WINDS), a collection of 47 meteorological towers located throughout KSC and CCAS, over a period of five winters. A Fortran program was written to calculate conditional probabilities of meeting or exceeding a given threshold speed during eight consecutive one-hour periods, using the current wind direction and peak wind speed as inputs. Forecast probabilities …

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Design And Validation Of An Accurate Gps Signal And Receiver Truth Model For Comparing Advanced Receiver Processing Techniques, Phillip Martin Corbell Mar 2000

Design And Validation Of An Accurate Gps Signal And Receiver Truth Model For Comparing Advanced Receiver Processing Techniques, Phillip Martin Corbell

Theses and Dissertations

Recent increases in the computational power of computers and digital signal processors have made possible new, novel signal tracking techniques in GPS receivers. One such technique is known as Direct Correlators Output Processing (DCOP). This technique replaces individual traditional tracking loops with a single Kalman Filter, which jointly processes the received signals while exploiting their correlated noises. DCOP is innovative in its potential to replace the tried and true classical signal tracking loops. It is also an enabling technology for ultra-tightly coupled GPS/INS (Global Positioning System/Inertial Navigation System). Potential benefits of these new tracking techniques include an order-of-magnitude improvement in …

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An Object-Oriented Repository-Based Software Synthesis System, Gary L. Cornn Jr. Mar 2000

An Object-Oriented Repository-Based Software Synthesis System, Gary L. Cornn Jr.

Theses and Dissertations

This research provides a repository on which various Air Force Institute of Technology (AFIT) transformational software synthesis tools can store, share, and manage data using a common repository information model. This information model was created by integrating a variety of separately developed AFIT software synthesis object models into a "wide-spectrum" model. Additionally, a methodology for describing complex relationships between artifacts in the repository is described. These relationships can be used to relate software synthesis artifacts created in a variety of formats, including text, binary, and the AFIT Wide-Spectrum Object Modeling Environment (AWSOME) information model. The relationships can be exploited for …

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Multi-Conjugate Adaptive Optics For The Compensation Of Amplitude And Phase Distortions, Peter N. Crabtree Mar 2000

Multi-Conjugate Adaptive Optics For The Compensation Of Amplitude And Phase Distortions, Peter N. Crabtree

Theses and Dissertations

Two deformable mirrors (DMs) with finite conjugate ranges are investigated for compensating amplitude and phase distortions due to laser propagation through turbulent atmospheres. Simulations are performed based on Adaptive Optics (AO) for an Airborne Laser-type scenario. The Strehl ratio, the number of branch points in DM controls, and the number of iterations to convergence are used as figures of merit to evaluate performance of the Sequential Generalized Projection Algorithm that generates mirror commands. The results are ensemble averages over 32 realizations of the scintillated test fields for each value of the Rytov parameter within the test scenario. The Gaussian beam …

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Modeling Piezoceramic Twist Actuation In Single-Cell Anisotropic Torque Box Of Low-Observable Uav Wing, Peter Cseke Jr. Mar 2000

Modeling Piezoceramic Twist Actuation In Single-Cell Anisotropic Torque Box Of Low-Observable Uav Wing, Peter Cseke Jr.

Theses and Dissertations

The reduction of an aircraft's radar cross section can increase its survivability in hostile airspace by making it more difficult to locate and track by enemy radar. Replacing articulated flight control surfaces with adaptive controls will reduce surface discontinuities, and enhance low observability. Actuation of the aerodynamic surfaces is achieved by an electric field applied to PZT actuators embedded in the top and bottom skins, creating differential strain and shear in the host substrate. This creates torsion about the elastic axis, and a change in the wing lift coefficient. The torsion of the designed baseline UAV's wing torquebox was modeled …

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A 3d Display System For Lightning Detection And Ranging (Ldar) Data, Michael W. Darwin Mar 2000

A 3d Display System For Lightning Detection And Ranging (Ldar) Data, Michael W. Darwin

Theses and Dissertations

Lightning detection is an essential part of safety and resource protection at Cape Canaveral. In order to meet the unique needs of launching space vehicles in the thunderstorm prone Florida environment, Cape Canaveral has the only operational three- dimensional (3D) lightning detection network in the world, the Lightning Detection and Ranging (LDAR) system. Although lightning activity is detected in three dimensions, the current LDAR display, developed 20 years ago, is two-dimensional. This thesis uses modern three-dimensional graphics, object-oriented software design, and innovative visualization techniques to develop a 3D visualization application for LDAR data.

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Linking Engineer Career Orientation And Human Resource Management Practices: Does Fit Affect Retention?, Cynthia M. Davis Mar 2000

Linking Engineer Career Orientation And Human Resource Management Practices: Does Fit Affect Retention?, Cynthia M. Davis

Theses and Dissertations

Turnover of the Air Force civil engineering (CE) officers is becoming increasingly important, as levels of CE Captains consistently decreases. Allen and Katz (1986) identified three career orientations of engineers based on their job preference-project, professional, and management engineers. Shepard (1958) suggested a dual-ladder promotion system to meet the cancer desires of technical and management workers. Additional research has proposed "desired" Human Resource Management (HRM) practices to facilitate the retention of each type of career-based engineer (Lee and Maurer, 1997). In an effort to determine if these career orientations, along with Air Force HRM practices, were linked to declining retention, …

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An Incentive Model For International Telecommunications, Jeffrey R. Del Vecchio Mar 2000

An Incentive Model For International Telecommunications, Jeffrey R. Del Vecchio

Theses and Dissertations

This study developed a new defensive model for global voice communications. It uses a n-person, zero-sum, cooperative and non-cooperative game to optimize the coalitions revenue after the possibility of a network service provider being tampered by an adversary. This research optimized two measures of effectiveness (coalition revenue and network provider revenue) of international telecommunications coalitions by hardening network service providers and improving their respective revenue with incentives. A multi-criteria optimization problem was developed to establish the strategic competition between the coalition defender and attacker. Irrespective of the amount of incentives, a applicable hardening and tampering strategy can be obtained. All …

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An Evaluation Of Microburst Prediction Indices For The Kennedy Space Center And Cape Canaveral Air Station (Ksc/Ccas), Steven N. Dickerson Mar 2000

An Evaluation Of Microburst Prediction Indices For The Kennedy Space Center And Cape Canaveral Air Station (Ksc/Ccas), Steven N. Dickerson

Theses and Dissertations

A wet-microburst event on 16 August 1994 at the Kennedy Space Center's Shuttle Landing Facility alerted forecasters from the 45th Weather Squadron (45WS), the provider of weather support to the Kennedy Space Center (KSC) and Cape Canaveral Air Station (CCAS), to the challenges of wet-microburst prediction. Although there was no operational impact, this event caused the 45WS to revise their severe thunderstorm forecasting procedures to specifically address microbursts, resulting in the locally developed Microburst-Day Potential Index (MDPI). MDPI provides a several-hour outlook of microburst potential based on the results of the Microburst and Severe Thunderstorm (MIST) project. The 45WS also …

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Quantifying The Protonospheric Effect On Prism, Kelly B. Doser Mar 2000

Quantifying The Protonospheric Effect On Prism, Kelly B. Doser

Theses and Dissertations

The total electron content (TEC) contribution to a Parameterized Real-time Ionospheric Specification Model (PRISM) calculation has been studied using protonospheric TEC measurements made by Global Positioning Satellites (GPS). Including the protonosphere proved challenging to both the calibration of GPS measurements and execution of PRISM. Though 46 days of GPS measurements were acquired, only 40 were successfully calibrated, and only 35 of those were used in the study. Data issues such as availability and completeness as well as measurement quality affected 6 of the days used. Calibration was done at Pittsburgh by excluding all measurements below 40.750 N. latitude cutoff. This …

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Distributed Object System Engineering For Terminal Aerodrome Forecast Validation And Metrics Processing, James S. Douglas Mar 2000

Distributed Object System Engineering For Terminal Aerodrome Forecast Validation And Metrics Processing, James S. Douglas

Theses and Dissertations

Distributed object systems are a very complex intertwining of heterogeneous hardware, software, and operating systems coupled with communication networks of varying protocols and capacities. Distributed components offer improved performance through parallel processing, improved expansion and scalability opportunities through modularity, improved availability through replication, and improved resource sharing and interoperability through interconnection. This research provides a distributed system design methodology to validate terminal forecasts and gather metrics for the Air Force Weather Agency. Proven principles such as component reuse and architectural development are applied through the use of parameterized types and design patterns. A client/server measurement model is developed to show …

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An Experimental Investigation On Periodic Forced Vibrations Of A Bladed Disk, Colin J. Duffield Mar 2000

An Experimental Investigation On Periodic Forced Vibrations Of A Bladed Disk, Colin J. Duffield

Theses and Dissertations

Aircraft engine blades are subject to harmonic forcing produced from periodic wakes created by fixed stators. Prolong or repeated exposure at blade resonant frequencies can cause vibration-induced fatigue, otherwise known as High Cycle Fatigue (HCF). Structural mistuning coupled with HCF causes premature blade failures, excessive operational costs and increased engine servicing. This study offered a novel approach to characterize mistuning effects on bladed disk forced vibration behavior. A model fan reduced in dynamic scale from an operational jet engine fan and with weak inter-blade coupling was fabricated. Aerodynamic disturbances produced by the stators were replicated by magnets attached to a …

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