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1992

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Development Of A Prototype Air Force Institute Of Technology (Afit) Research Management System (Arms), David N. Schaaf, Carl W. Scott Dec 1992

Development Of A Prototype Air Force Institute Of Technology (Afit) Research Management System (Arms), David N. Schaaf, Carl W. Scott

Theses and Dissertations

The goal of this study was to design, develop, test, and evaluate an initial prototype information system to enhance the conduct and management of research in the School of Systems and Logistics at the Air Force Institute of Technology (AFIT). To accomplish this goal, the researchers developed and completed a methodology that was generally patterned after the milestones in a typical system development life cycle. The proof-of-concept nature of this research caused the researchers to also map the study's seven major objectives into a second system development model called the Spiral Model (Boehm, 1988:61). This hybrid approach provided better defined …

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Integrated Blade Inspection System (Ibis) Upgrade Study, Tony J. Deliberato, Steven W. Perkins, Steven K. Saplin, John G. Snyder, Gregory J. Toussaint Dec 1992

Integrated Blade Inspection System (Ibis) Upgrade Study, Tony J. Deliberato, Steven W. Perkins, Steven K. Saplin, John G. Snyder, Gregory J. Toussaint

Theses and Dissertations

The purpose of this design study was to identify ways to improve the Integrated Blade Inspection System. The Air Force requires inspection of jet engine compressor and turbine blades to locate defects and prevent engine failure. The current inspection process uses fluorescent penetrant as an aid to identify cracked blades. A systems engineering design process was applied to evaluate the current inspection techniques and to develop alternative methods to satisfy the Air Force requirements. Three different inspection systems were developed and compared to the current process: manual, semi-automated, and fully automated inspection. This study made several noteworthy contributions: development of …

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An Analysis Of Usspacecom's Space Surveillance Network (Ssn) Sensor Tasking Methodology, Jeff M. Berger, Joseph B. Moles, David G. Wisley Dec 1992

An Analysis Of Usspacecom's Space Surveillance Network (Ssn) Sensor Tasking Methodology, Jeff M. Berger, Joseph B. Moles, David G. Wisley

Theses and Dissertations

This study provides the basis for the development of a cost/benefit assessment model to determine the effects of alterations to the Space Surveillance Network (SSN) on orbital element (OE) set accuracy. It provides a review of current methods used by NORAD and the SSN to gather and process observations, an alternative to the current Gabbard classification method, and the development of a model to determine the effects of observation rate and correction interval on OE set accuracy. The proposed classification scheme is based on satellite J2 perturbations. Specifically, classes were established based on mean motion, eccentricity, and inclination Since J2 …

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An Assessment Of Software Safety As Applied To The Department Of Defense Software Development Process, Peter W. Colan, Robert W. Prouhet Dec 1992

An Assessment Of Software Safety As Applied To The Department Of Defense Software Development Process, Peter W. Colan, Robert W. Prouhet

Theses and Dissertations

This research analyzed the relationships between the DOD software development process, system safety requirements, and current structured software safety analysis techniques. The current state of software safety was assessed within the aerospace industry and DOD, and a training program for DOD System Safety Managers was developed. A telephone survey was conducted to gather information on current software safety analysis techniques and methodologies. Personal interviews were conducted with Aeronautical System Center System Safety Managers to gather data on job perception and perceived training needs. The results of the study indicate that the DOD guidance and policy documents needed to implement and …

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Analysis Of Whole-Sky Imager Data To Determine The Validity Of Pcflos Models, Richard W. Boltz, George R. Kather Dec 1992

Analysis Of Whole-Sky Imager Data To Determine The Validity Of Pcflos Models, Richard W. Boltz, George R. Kather

Theses and Dissertations

Models used to predict the probability of a cloud-free line-of-sight (PCFLOS) from the ground to space have existed since the 1960s. Unfortunately, an adequate data set has not been available to check the validity of these models until the deployment of the Whole-Sky Imager (WSI) system in 1989. Now that a three-year database has been collected from the WSI system, it is possible to validate, or refute, the existing models. This study investigates the most generally accepted models. Specifically, we investigate three questions: (1) Is the Lund and Shank-lin PCFLOS model assumption of azimuthal independence valid; (2) Does the Lund …

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Improving The Quality Of Machine Translations By Providing Stylistic Guidelines To Authors And Editors, Edward J. Walsh Dec 1992

Improving The Quality Of Machine Translations By Providing Stylistic Guidelines To Authors And Editors, Edward J. Walsh

Theses and Dissertations

This research sought to identify stylistic guidelines which could be used by the authors and editors of English language texts in order to improve the quality of subsequent machine translations to other languages. A literature review was conducted to provide background information and to determine what guidelines would be appropriate. Nine guidelines were developed on the basis of the review. The guidelines were then tested. They were applied to five paragraphs from a Royal Australian Air Force technical publication by the researcher and an independent volunteer. Both the resulting texts and the original paragraphs were translated into French using the …

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An Analysis Of The Effectiveness Of Air Force Information Management Officer Training Based On The Perceived Needs Of Current Information Management Officers, David P. Biros, Stewart J. Cole Dec 1992

An Analysis Of The Effectiveness Of Air Force Information Management Officer Training Based On The Perceived Needs Of Current Information Management Officers, David P. Biros, Stewart J. Cole

Theses and Dissertations

The purpose of this study was to determine if the computer orientation courses provided Air Force information managers are properly focused. This study found that the courses have made the desired impact and, with minor exceptions, information managers perceive then-selves to be more knowledgeable after the training. From the results of the survey it is apparent that information managers are more knowledgeable of computers than they were in a study completed in 1988. The officers who attended training after the course was modified to include computer orientation were much more satisfied with their training than previous graduates. They indicated a …

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Satcom General Purpose Modem Dscs Iii Sct Beacon Telemetry Display, James D. Coppola Dec 1992

Satcom General Purpose Modem Dscs Iii Sct Beacon Telemetry Display, James D. Coppola

Theses and Dissertations

This thesis documents the design and implementation of a DSCS III single Channel Transponder (SCT) beacon telemetry display. The system is a personal computer based design which interfaces to three SCT beacon receiver/demodulators. The software was designed to decode and display both the DSCS III A and DSCS HI B satellite beacons. Recordings of the SCT beacon display can be made on paper and/or magnetic media when triggered by the user, a watchdog timer, or the SCT command accept telemetry bit. In addition, the system can be configured with an IRIG B Universal Time Coordinates (UTC) card which enables the …

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An Analytical And Experimental Investigation Of Fm-By-Noise Jamming, Charles J. Daly Dec 1992

An Analytical And Experimental Investigation Of Fm-By-Noise Jamming, Charles J. Daly

Theses and Dissertations

Among the jamming waveforms used in Electronic Warfare, FM-by-noise is the least understood, and no exhaustive analytical and experimental investigation of the subject exists. This investigation presents a thorough review, consolidation, and elucidation of the theory of FM-by-noise. To explain and predict the behavior of FM-by-noise at RF and IF, three useful ratios, namely the deviation-to-victim ratio, the noise-to-victim ratio, and the sweep- to-victim ratio, are developed. To complement the theory, results of FM-by-noise jamming experiments conducted using commercial test and measurement equipment are presented. Specifically, the time- and frequency-domain behavior of FM-by- noise at RF and IF is studied …

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Formalizing, Validating, And Verifying Real-Time System Requirements With Reacto And Vhdl, Frank C. Young Dec 1992

Formalizing, Validating, And Verifying Real-Time System Requirements With Reacto And Vhdl, Frank C. Young

Theses and Dissertations

We develop a methodology for formalizing, verifying, and validating the requirements specification of real-time systems based on a graphical and formal hierarchical Finite State Machine (FSM) language Reacto. We define a means to quantify time and express real-time constraints in Reacto and a transformation from Reacto to the Very High Speed Integrated Circuit (VHSIC) hardware Description Language (VHDL). Reacto's high level abstractions, graphical nature, and theorem prover produce efficient, accurate, and easily understood specifications. We use VHDL's event driven simulation capability, concurrency, and temporal operators to thoroughly examine temporal dependencies between the state machine transitions, and to increase simulation power …

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An Investigation Of Structural Locality In The Memory Referencing Behavior Of Computer Programs, Michael E. Bletzinger Dec 1992

An Investigation Of Structural Locality In The Memory Referencing Behavior Of Computer Programs, Michael E. Bletzinger

Theses and Dissertations

The nature of structural locality as defined by same stack distance access is investigated in this thesis. The question is whether structural locality can be characterized as an inherent type of behavior. The results revealed that structural locality is strongly influenced by a program's design and phase of execution. Entropy measurements revealed that the predictiveness of structural locality is also influenced by program design. A Markov model was refined to capture the characteristics of structural locality that were measured. Trace synthesis demonstrated some success in reproducing same stack distance run distributions when the model had enough states to encompass the …

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Analysis And Simulation Of Modified Tanlock And Delay Lock Loops For Gps Receiver Design, James A. Hird Dec 1992

Analysis And Simulation Of Modified Tanlock And Delay Lock Loops For Gps Receiver Design, James A. Hird

Theses and Dissertations

The purpose of this thesis is to investigate two types of tracking loops used in Global Positioning System (GPS) receiver design. The first loop, the Delay Lock Loop (DLL), is a code tracking loop used to synchronize a locally generated pseudo-noise (PN) sequence with the PN sequence in the GPS satellite broadcast. Synchronization of the PN sequences is essential for de-spreading the direct-sequence spread spectrum (DS/SS) broadcast and demodulating the transmitted data. The second loop, the Modified Tanlock Loop (MTLL), is a carrier tracking loop used to synchronize the phase of a voltage controlled oscillator (VCO) with the carrier of …

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Failure Identification Using Multiple Model Adaptive Estimation For The Lambda Flight Vehicle, Peter D. Hanlon Dec 1992

Failure Identification Using Multiple Model Adaptive Estimation For The Lambda Flight Vehicle, Peter D. Hanlon

Theses and Dissertations

This study develops and investigates the performance of a Multiple Model Adaptive Estimator (MMAE) to detect and identify control surface and sensor failures on the LAMBDA flight vehicle (a URV developed by Wright Laboratories). The MMAE uses a bank of Kalman filters that predict the aircraft response to a given input, with each filter model based on a different failure hypothesis, and then forms the residual difference between the prediction and sensor measurements for each filter. The MMAE uses these residuals to determine the probabilities of the failures that are modeled by the Kalman filters. Initially the MMAE identified all …

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Etann Hardware Implementation For Radar Emitter Identification, James B. Calvin Jr. Dec 1992

Etann Hardware Implementation For Radar Emitter Identification, James B. Calvin Jr.

Theses and Dissertations

This study investigated classification of 30 radar emitters with 16 signal features using Intel's 80170NX chip, the Electronically Trainable Analog Neural Network (ETANN). Software tools were developed to characterize the ETANN sigmoidal transfer function for use in a custom simulator, known as Neural Graphics. Neural Graphics operates on a Silicon Graphics workstation. The Intel Neural Network Training System simulators were used in early experiments, but were found to be inefficient in training on data used in this research. Using a modified Neural Graphics simulator, single chip and multi-chip experiments were performed to provide benchmark results prior to performing chip-in-loop training. …

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Remote Sensing Of Turbulence And Transverse Atmospheric Wind Profiles Using Optical Reference Sources, Steven C. Koeffler Dec 1992

Remote Sensing Of Turbulence And Transverse Atmospheric Wind Profiles Using Optical Reference Sources, Steven C. Koeffler

Theses and Dissertations

This thesis examines a remote sensing technique for measuring the atmospheric structure constant and the transverse atmospheric wind velocity as a function of altitude by performing temporal and spatial correlations of band pass filtered wave front slope sensor measurements. Two point sources are used to illuminate two pairs-of cc>-located wave front slope sensors. The sources and sensors are arranged to give rise to crossed optical paths. For each pair of wave front slope sensors, the output of the larger sensor is subtracted from the output of the smaller sensor. This band pass filters the smaller sensor's output. The filtered …

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Cepstral And Auditory Model Features For Speaker Recognition, John M. Colombi Dec 1992

Cepstral And Auditory Model Features For Speaker Recognition, John M. Colombi

Theses and Dissertations

The TIMIT and KING databases, as well as a ten day AFIT speaker corpus, are used to compare proven spectral processing techniques to an auditory neural representation for speaker identification. The feature sets compared were Linear Predictive Coding (LPC) cepstral coefficients and auditory nerve firing rates using the Payton model. This auditory model provides for the mechanisms found in the human middle and inner auditory periphery as well as neural transduction. Clustering algorithms were used to generate speaker specific codebooks - one statistically based and the other a neural approach. These algorithms are the Linde-Buzo-Gray (LBG) algorithm and a Kohonen …

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Digital Signal Processing Using Lapped Transforms With Variable Parameter Windows And Orthonormal Bases, Brian D. Raduenz Dec 1992

Digital Signal Processing Using Lapped Transforms With Variable Parameter Windows And Orthonormal Bases, Brian D. Raduenz

Theses and Dissertations

This thesis develops and evaluates a number of new concepts and tools for the analysis of signals using variable overlapped windows and orthonormal bases. Windowing, often employed as a spectral estimation technique, can result in irreparable distortions in the transformed signal. By placing conditions on the window and incorporating it into the orthonormal representation, any signal distortion resulting from the transformation can be eliminated or cancelled in reconstruction. This concept is critical to the theory underpinning this thesis. As part of this evaluation, a tensor product based general N-point fast Fourier transform algorithm was implemented in the DOD standard language, …

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Automated Face Recognition System, Kenneth R. Runyon Dec 1992

Automated Face Recognition System, Kenneth R. Runyon

Theses and Dissertations

In this thesis three variations of an end-to-end face recognition prototype system are developed, implemented and tested. Each version includes real-time image collection, automated segmentation, preprocessing, feature extraction, and classification. The first version uses a Karhunen Loeve Transform (KLT) feature extractor and a K-nearest neighbor classifier. Version two uses the same feature set but utilizes a multilayer perception neural network with a back propagation learning rule. Finally the third version uses a Discrete Cosine Transform as the feature extractor and the K-nearest neighbor as the classifier. Only the KLT versions of the system were tested. The tests were based on …

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Acquisition Of Direct Sequence Spread Spectrum Signals Using Digital Signal Processing Techniques, Ronald E. Schmitz Dec 1992

Acquisition Of Direct Sequence Spread Spectrum Signals Using Digital Signal Processing Techniques, Ronald E. Schmitz

Theses and Dissertations

This thesis investigates the use of digital signal processing (DSP) techniques to achieve initial synchronization with Global Positioning System (GPS) Pseudo-Noise (PN) signals. Synchronization with the transmitted PN signal is essential to the despreading of the transmitted Direct Sequence Spread Spectrum (DS/SS) signals and decoding of the transmitted satellite data. The use of DSP methods to decrease the time required to achieve initial synchronization is investigated. This thesis proposes an initial acquisition section of the GPS receiver and derives the equations to show the method is mathematically feasible. Computer simulations of the proposed receiver using received signals corrupted by Doppler …

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Face Recognition With Neural Networks, Dennis L. Krepp Dec 1992

Face Recognition With Neural Networks, Dennis L. Krepp

Theses and Dissertations

This study investigated neural networks for face verification and classification. The research concentrated on developing a neural network based feature extractor and/or classifier to perform authorized user verification in a realistic work environment. Recognition accuracy, system assumptions, training time, and execution time were analyzed to determine the feasibility of a neural network approach. Data was collected using a camcorder and two segmentation schemes: manual segmentation and motion-based, automatic segmentation. Data consisted of over 2000. 32x32 pixel, 8 bit gray scale images of 52 subjects; each subject had two to ten days worth of images collected. Several training and test sets …

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Signal Approximation With A Wavelet Neural Network, Charles M. Westphal Dec 1992

Signal Approximation With A Wavelet Neural Network, Charles M. Westphal

Theses and Dissertations

This study investigated the use of Wavelet Neural Networks (WNN) for signal approximation. The particular wavelet function used in this analysis consisted of a summation of sigmoidal functions (a sigmoidal wavelet). The sigmoidal wavelet has the advantage of being easily implemented in hardware via specialized electronic devices like the Intel Electronically Trainable Analog Neural Network (ETANN) chip. The WNN representation allows the determination of the number of hidden-layer nodes required to achieve a desired level of approximation accuracy. Results show that a bandlimited signal can be accurately approximated with a WNN trained with irregularly sampled data. Signal approximation, Wavelet neural …

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Women And Leadership: The Effect Of Gender, Gender-Role Orientation, Socioeconomic Status, And Parental Influence On Women’S Aspirations To Leader Roles, Barbara Katherine Kreuzer Dec 1992

Women And Leadership: The Effect Of Gender, Gender-Role Orientation, Socioeconomic Status, And Parental Influence On Women’S Aspirations To Leader Roles, Barbara Katherine Kreuzer

Dissertations

The objective of this study was to determine which factor or combination of factors are related to the degree to which university women aspire to leadership positions. A random sample of university seniors (N=311) from the business, teacher education, and political science curricula were surveyed by mail. The study attempted to answer the following seven research questions: (1) Are there gender differences among university seniors' aspirations to leader positions, (2) are there differences among university seniors' aspirations to leadership based upon curriculum, (3) are there gender differences among university seniors in their projections of classmates into career roles, (4) are …

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Hyper-Consistent Estimation Of A Unit Root In Time Series Regression, Peter C.B. Phillips Dec 1992

Hyper-Consistent Estimation Of A Unit Root In Time Series Regression, Peter C.B. Phillips

Cowles Foundation Discussion Papers

It is shown that the fully modified ordinary least squares (FM-OLS) estimator of a unit root in time series regression is T 3 /2 -consistent. Relative to FM-OLS, therefore, the least squares and maximum likelihood estimators are infinitely deficient asymptotically. Simulations show that this dominance of FM-OLS persists even in small samples.

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Central Florida Future, Vol. 25 No. 28, December 1, 1992 Dec 1992

Central Florida Future, Vol. 25 No. 28, December 1, 1992

Central Florida Future

Student appeals: questions actions of SG coordinator; Film program places first in Fort Lauderdale: Orlando area schools shed second rate reputations as they capture majority of film awards; Opinion: Japanese 'Love Boat' brimming with plutonium; Features: Eddie Murphy interview: Talks politics in Washington D.C.; Sports: Women's basketball team prepares for the 1992-93 season.

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Design Research: The Newsletter Of The Design Research Society No.48, Robin Jacques Dec 1992

Design Research: The Newsletter Of The Design Research Society No.48, Robin Jacques

Design Research Newsletters (1966-1999)

No abstract provided.

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A Preliminary Preview Of Compensatory Forest Plantation In Peninsular Malaysia, Tuck Chin Dec 1992

A Preliminary Preview Of Compensatory Forest Plantation In Peninsular Malaysia, Tuck Chin

Electronic Theses and Dissertations

Projections of supply and demand for timber appear to indicate a domestic shortage in Peninsular Malaysia by the year 2000. Timber shortage will result in loss of foreign exchange, retrenchment of timber workers, inflate prices and depress construction and housing industries. Compensatory Forest Plantation Program (CFPP) is one of the methods taken by the Malaysian Government to avert this impending crisis. CFPP was officially launched in 1983, in four States of Peninsular Malaysia. By 1989, forest plantations totaling 36,874 hectares were established. A final analysis of CFPP is premature, as the program is only in its seventh year of a …

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An Alternative Theory Of Firm And Industry Dynamics, Richard Ericson, Ariel Pakes Dec 1992

An Alternative Theory Of Firm And Industry Dynamics, Richard Ericson, Ariel Pakes

Cowles Foundation Discussion Papers

This paper provides a model of firm and industry dynamics that allows for entry, exit and firm-specific uncertainty generating variability in the fortunes of firms. It focuses on the impact of uncertainty arising from investment in research and exploration-type processes. It analyzes the behavior of individual firms exploring profit opportunities in an evolving marketplace and derives optimal policies, including exit, in this environment. Then it adds an entry process and aggregates the optimal behavior of all firms, including potential entrants, into a rational expectations, Markov perfect industry equilibrium, and proves ergodicity of the equilibrium process. Numerical examples are used to …

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การพยาบาลในสาธารณรัฐประชาธิปไตยประชาชนลาว, พวงรัตน์ บุญญานุรักษ์ Dec 1992

การพยาบาลในสาธารณรัฐประชาธิปไตยประชาชนลาว, พวงรัตน์ บุญญานุรักษ์

Journal of Nursing Research, Innovation, and Health

No abstract provided.

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ปัจจัยคัดสรรที่สัมพันธ์กับแบบแผนการดำเนินชีวิต ของผู้สูงอายุโรคข้อเสื่อม, ณัฐนาฏ ไชยศิริ, จินตนา ยูนิพันธุ์ Dec 1992

ปัจจัยคัดสรรที่สัมพันธ์กับแบบแผนการดำเนินชีวิต ของผู้สูงอายุโรคข้อเสื่อม, ณัฐนาฏ ไชยศิริ, จินตนา ยูนิพันธุ์

Journal of Nursing Research, Innovation, and Health

No abstract provided.

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การให้คำปรึกษา : ความจำเป็นต่อการพัฒนา สุขภาพอนามัย, จินตนา ยูนิพันธุ์ Dec 1992

การให้คำปรึกษา : ความจำเป็นต่อการพัฒนา สุขภาพอนามัย, จินตนา ยูนิพันธุ์

Journal of Nursing Research, Innovation, and Health

No abstract provided.

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