Digital Commons Network^™

A Fully Coupled, Automated Formation Control System For Dissimilar Aircraft In Maneuvering Formation Flight, Paul R. Rohs

Theses and Dissertations

This study developed a fully automated formulation control system, capable of controlling a number of like or dissimilar aircraft in maneuvering formation flight. C-130 fixed wing aircraft and H-53 helicopters were modelled in various formulations and simulated through a mix of maneuvers. External formation guidance was assumed as a single data burst of nominal function guidance commands and separation distances for each wing aircraft in the formation. No communication was assumed between formation aircraft. Wing aircraft track lead aircraft maneuvering with an ideal on-board sensor, maneuvering to maintain relative position. It was determined that lead aircraft inputs must be attenuated …

Hardware Upgrade Of A Segmented Drum Assay System, Claude A. Irvine

Theses and Dissertations

This paper describes the conversion of a DEC PDP-11/05 computer system, previously used in Canberra's Model 2220B segmented gamma scanner, with an IBM PC. Two tasks necessary for completion of the project involved reestablishing communications with a Canberra Series 35+ multi-channel analyzer and a scan table controller. An additional serial/parallel card was installed in the PC to reinstate comunications with the multi-channel analyzer. For computer control of scan table controller operations a digital input/output card was used along with an external electromechanical relay board; when implemented together this hardware setup replaces functions that were normally processed through a motion control …

Analysis Of The Effects Of The Commander's Battle Positioning On Unit Combat Performance, Thomas I. Pratt

Theses and Dissertations

The purpose of this study was to determine the effect of the Commander's battle positioning on unit combat performance. Research was focused on analyzing the location of the Battalion/Task Force Commander during daytime deliberate attacks conducted at the U.S. Army's National Training Center, Fort Irwin, CA. Forty battles, from January 1986 to September 1989, provided the basis for this study. Information that described the Commander's location, a general description of the battle, and unit measures of effectiveness, was collected for each battle and put in a format that allowed for ease of analysis. This study database was explored using numerous …

A Network Flow And Goal Programming Approach To Modeling The Impact Of Pre-Accession Training To The Trained Personnel Requirements Process, William J. Beveridge

Theses and Dissertations

HQ ATC was tasked to analyze the impact of pre-accession training to the Trained Personnel Required (TPR) and training production process. Pre- accession training is a policy of providing contracted initial skills training to enlistees prior to entering basic military training. The purpose of this study was to develop a method to model the impact of pre-accession training. A network modeling and goal programming approach was used. Comparisons between the current training policy and a pre-accession training policy were made. Sensitivity was conducted on the impact of a balk rate on the new policy. The balk rate is the percent …

Saber: A Theater Level Wargame, William F. Mann Iii

Theses and Dissertations

This thesis provides a foundation to build a new theater level computerized wargame for the Air Force Wargaming Center, Maxwell AFB, AL to replace the Theater War Exercise (TWX), also known as Agile. Given a recently developed land battle, this thesis' effort links US Air Force doctrine with a conceptual model's framework and designs a new air battle module. The integration of both the air and land battles forms a new game, Saber. This thesis redefines the ground combat units of the land battle, and adds theater air defense units, bases and aircraft packages. This thesis introduces stochastic attrition between …

The Utility Of Elliptical And Circular Confidence Regions For Hfdf Receivers, Paul T. Nemec

Theses and Dissertations

This thesis investigates HFDF confidence region (CR) shape exhibited by geolocations in a search-and-rescue context. In Phase I, a Keeney-Raiffa multiattribute utility function was developed which allowed an analytical measure of preference between elliptical and equivalent- probability circular CRs. Phase II utilized a likelihood approach to establish CR shape for sample operational geolocations having multiple points of bearing intersections. For 12 sample Phase I geolocations, the elliptical CR always had higher utility than its corresponding circular CR. For accepted sample geolocations, a preference condition was developed whereby a circular CR would only be preferred over the corresponding elliptical CR if …

Multicriteria Network Routing Of Tactical Aircraft In A Threat Radar Environment, Ernst K. Isensee

Theses and Dissertations

Real-time route planning for tactical aircraft has established a requirement for analytical tools which prescribe optimal solutions. The Air Force Electronic Warfare Center has developed a computerized routing aid which enhances the ability to plan tactical flight missions under real-time constraints. The decision aid known as the Improved Many-on-Many (IMOM) allows the user to subjectively evaluate flight routes within enemy radar coverages. However, the mission planner is required to intuitively assesses the survivability risks associated for each user defined route. As an alternative to this method, the deterministic procedures of dynamic programming and the shortest path algorithms offer techniques which …

Incorporating Value Systems In Strategic Force Analysis, Nancy D. Snyder

Theses and Dissertations

Deterring potential Soviet aggression depends on our ability to hold at risk those assets they value most. This research investigates target valuation as an added dimension to force structure analysis. An extensive literature review is followed by the development and demonstration of a methodology defining development and use target values. The literature review covers arms control concepts to give a foundation for an important use of force structure analysis. It also covers measures of effectiveness. The final part of the review is comprised of definitions of perspectives on nuclear war. The methodology defines motivations for force structuring in the form …

An Environmentally Controlled Chamber For The Study Of Radon Detection, William R. Wharton Jr.

Theses and Dissertations

A system was developed to dynamically control and monitor the environment and radon concentration within a glovebox chamber for the study of radon. The system is designed around a personal computer workstation which automates the entire system. The radon concentration is determined by monitoring the count rate from radon and its progeny which are continuously circulated from the radon chamber through a Lucas Cell detection system. This information is then used as a base for controlling a radon injection system. When the concentration within the glovebox drops, the system injects a precisely-measured volume of high activity radon gas into the …

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Building Services Engineering

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The Evolution Of The Wpi Advanced Space Design Program - An Evolving Program Of Technical And Social Analysis Using The Nasa Space Shuttle For Engineering Education, Fred J. Looft, Robert C. Labonte, William W. Durgin

Office of the Provost Scholarship

In December of 1982, Worcester Polytechnic Institute, with the cooperation and support of the MITRE Corporation, initiated a primarily undergraduate educational program to develop experiments to be flown onboard a NASA Space Shuttle. Christened the MITRE WPI Space Shuttle Program, it sponsored the development of five educationally meritorious experiments over a period of four years. Although the experiments were ready to fly in early 1986, the Challenger disaster delayed their flight until the Spring of 1991. The delay notwithstanding, the benefits of the first program were sufficient to justify the development of a second set of experiments. More comprehensive in …

Acuta Enews February 1991, Vol. 20, No. 2

ACUTA Newsletters

In This Issue

ACUTA gains new tax status

Stopping a runaway dialer

Just what is an engineer?

FCC ruling awaited

Party Line

In-house accounting

The Optimal Location Of Geodss Sensors In Canada, Pierre J. Forgues

Theses and Dissertations

This thesis studies the maximal coverage p-median and the set covering facility location problems as applied to the GEODSS location problem. The classical single-objective mathematical formulations of the p-median and set covering problems are converted into network-flow formulations and various solution methods are developed using a scaled-down version of the GEODSS problem. The next step is the introduction of a second criterion function into the problem. This second function consists of minimizing the sum of the variance in coverage at the selected locations. Research reveals the deficiencies of MOLP (multiobjective linear programming) techniques in generating the efficient frontier of an …

Direct Schottky Injection Image Sensors, Subramanyam V. Ayyagari

Theses

This thesis describes the analysis and simulations of Direct Schottky Injection (DSI) imagers which have 100% fill factor. Frame transfer (FT) and interline transfer (IT) DSI imager structures have been investigated. Theoretical Poisson solution for the PT and P-NP FT-DSI structures is presented, which closely agrees with simulation results. Simulation for frame transfer FT-DSI imagers has been done in SUPREM III since 1-D effects are more dominant. Single carrier transit time for both the structures were estimated from the electric fields.

Simulations of IT-DSI structures was done using PISCES llb, to get the local electric fields, which define the directionality …

Multiresolution Techniques : Laplacian Pyramid Coding And Its Comparison With Subband Coding, Danmei Chang

Theses

The multiresolution pyramid and related structures have been developed as intermediate representations between the purely frequency domain and purely spatial domain. In this thesis. we discuss two important pyramid structures which are often used in multiresolution representation: Laplacian pyramid and subband coding.

Laplacian pyramid. a typical pyramid structure, is studied in detail. By means of software implementation. we obtain a comprehensive understanding of its features and applications in image representation and data compression. Several modifications of pyramid structure are used to compress the data dynamic range, reduce the computational complexity and improve performance. Performance of the conventional Laplacian pyramid and …

Fast Packet Switching For B-Isdn With Neural Net Control, Ajit K. Chaudhuri

Theses

The concept of integrated network where both the voice packet and data packet are delt with, started taking shape since 1970. Later, Users? demand for communication of data, voice, file, facsimile, image, videotext, videophone, videomovie has also been felt. All these services need bit rate of transmission in the order of 10, even 100 Mbits. An economical way to transmit this higher bit rate, with flexibility of bandwidth, is to treat voice/video in the form of packets and transmit those packets in real time. Studies of this kind of communication is carried out in Broadband ISDN ( BISDN). At this …

A Machine Vision System With Remote Host, Chieyeon Jason Chen

Theses

The modem plays an important role in data communication using the Public Swiched Telephone Network. In this thesis, the modem function is merged into a low cost machine vision system based on the Motorola 68HC11. Evalation Board The system comprises the intelligent machine vision con- troller and a remotely located host computer, such as an IBM-PC. It, supports extra long distance communication capability so that the controller and the host can be anywhere in the world where then is a telephone line. Because of the limit of a 2100 bps modem, soft ware data compression is implemented here to save …

Development Of Techniques Of Artificial Intelligence In Identifying The Different Machined Surfaces, Yi-Ching Chou

Theses

This thesis deals with the identification of different machined surfaces with artificial inteligence techniques. There are five kinds of machining operations: grinding, turning, milling, EDM and waterjet which determine the characteristics of resulting surfaces. Topology of various specimens is measured using the surfanylizer. Twenty one parameters are extracted from the measurements to describe the characteristics. In this thesis, we develop neural and expert systems that recoginize and classify surfaces according to the machining methods.

Information Handling System With A Personal Computer To Assist In The Manufacturing Of Plastic Parts, Yi Chung

Theses

The ongoing personal computer development has led to its increasing application in manufacturing to improve productivity. Being more aware of this technology, most of these benefits have accrued to large firms. The intent of this thesis is to show that it is equally advantageous for small manufacturing companies to utilize them and show how they can do so.

The field of production control systems is discussed and those areas where personal computers can be applied are emphasized. Forecasting, warehouse management, material requirement planning, and inventory control are the most appropriate. An application example using dBase III plus to write the …

Ct Fan Beam Reconstruction With A Non-Stationary Axis-Of-Rotation, Joseph A. Concepcion

Theses

One important aspect for reconstructing an image using Computed Tomography (CT) is that the axis-of-rotation must pivot at the same point on the reconstruction plane as the x-ray source and CT scanner assembly rotates around the imaged object. This pivot point is used as a reference point for backprojecting pixel values to their proper coordinates. Therefore, reconstructing an image with a non-stationary axis-of-rotation would backproject pixel values to wrong coordinate points, since the reference point is non-stationary for every projection angle.

A convolution filtered backprojection algorithm has been derived for correcting images that were acquired with a non-stationary axis-of-rotation using …

Tri-Color Led Display System Using Microcontroller, Costakis A. Constantinou

Theses

A seven-by-forty-eight tricolor LED display panel is designed and built around the 68HC11 MCU.

Four bilateral switching transistors (4066) are used in a Wien bridge configuration to drive each tri-color LED. With this circuitry one is able to drive the tricolor LED symmetrically. An alternative design that uses only two switching transistors is also offered.

A software program was developed to output on the display scrolling and fixed messages. Each message could be displayed in a different color (Red, Green and Yellow) and at a different speed (Slow, Fast, and Medium). The program also includes an editor with insertion and …

Novel Way Of Sub-Carrier Coherent Detection And Clock Recovery In Fiber-Optic Communications, Narayan Gehlot

Theses

We experimentally demonstrate a novel concept for recovery of a Sub-Carrier and Timing Clock in fiber-optic communication systems using a Wavelength Division Multiplexing technique. The idea is to send a low radio frequency (RF) as a reference pilot from the transmitter to the receiver on a separate laser using the principle of Wavelength Division Multiplexing (WDM). This low frequency signal is taken to be a subharmonic of the subcarrier used to carry information and intensity modulate another laser. Such approach will be expected to generate at the receiver a local oscillator in high coherence with the subcarrier.

We show that …

Some Aspects Of Integration Of Classification, Computer Aided Design, Process Planning, And Scheduling Of Flexible Manufacturing Systems, Suresh Godavari

Theses

This work deals with the role, problems and solution technique for integration of Computer Assisted Design, Classification, Process Planning, and Scheduling for a Flexible Manufacturing System. A lark spectrum of rotational and prismatic parts are considered.

A Knowledge-based rough classification and coding system [C&C] has been developed for coding similar parts using a Group Technology [GT] technique. In this module VP-EXPERT and DBase III Plus are used as expert system and database respectively. This module interfaces with a database for the retrieval and selection process.

The code obtained from the C&C system is the basis for the succeeding phases. The …

The Bandwidth Allocation Of Atm Through Genetic Algorithm, Hong Pan

Theses

In this thesis, we develop an optimization method based on Genetic Algorithm to achieve the bandwidth allocation of ATM network. In Broadband Integrated Service Digital Network (BISDN), the Asynchronous Transfer Model (ATM) is already adopted as the transfer standard by CCITT. ATM is a high-bandwidth, low-delay, fast-packet switching and multiplexing technique. Using ATM technique, we can flexibly reconfigure the network and reassign the bandwidth to meet the requirement of all types of services. As an effective optimization method, Genetic Algorithm(GA) is applied to implement the bandwidth allocation of ATM. GA is a class of search algorithm based on the mechanics …

Dual Token Ring Lan Performance, Pratap S. Pasupuleti

Theses

A simulation model to analyze the performance of a dual token ring LAN is developed. The performance measures throughput, average packet delay and maximum delay per packet are obtained. System performance is analyzed for different loads, number of stations, and packet lengths. The performances of token ring LANs with a conventional structure and a dual ring structure are compared for both uniform packet sizes and a case with mixed packet sizes. In the uniform packet size case, the dual ring delays were lower at equivalent throughput because of propagation delay effects. In the mixed packet size case the maximum delays …

Comparative Study Of Prediction Gain Based On Neural Network Architecture, Prashant M. Shah

Theses

This thesis describes the Neural Network approach to design predictor using Delta and Generalized Delta Rule. The predictor is designed by supervised training based on the typical sequence of pixel values. Neural Network is used to find the coefficients of the predictor. Both 1-D and 2-D scheme of the pixels as well as linear and non-linear correlations are used to find the coefficients by training. Different combinations of pixels are used to find the "best" combination among the order of the predictor.

Experimental Study Of The Internal Loads In A Cardan Joint, Johannes K. Waal De

Theses

A recent investigation by Fischer and Freudenstein questioned the validity of the negligible axial forces assumption in the static force analysis of Cardan Joints. The purpose of this paper is to experimentally assess this assumption for the dynamic case.

To this end an experiment was constructed to determine the axial forces acting on the intermediate revolute joints of a Cardan joint. A four-square test arrangement was prepared such that shaft intersection angle, shaft torque, and shaft speed could be varied. Strain gages were applied to the "arms" of the joint to measure the resulting strains due to the forces along …

Integrated Digital Speech System With Pc, Zhen Zhu

Theses

A PC-based real-time digital speech processing system is designed. Speech synthesis, analysis, storage and retrieval are implemented in the system with intelligent telephone functions. Speech data are stored on floppy disk and easy to retrieve. Though floppy disk is slow in speed, real-time processing is achieved with low bit rate coding. The computer gets speech data from a digital speech processing unit or send data to it through a synchronous seiial communication port. The analog input of digital speech processing unit can be selected from the telephone line or the microphone, and output of the digital speech processing unit can …

N-Cross Coupled Phase Locked Loops, Joseph C. Aboukhalil

Theses

Interference cancelation has been mainly performed using arrays, in an important issue in communication both array and spatial cancelation and time domain approach were used. In array applications, depth of cancelation may dependent on the interferences to background power ratio and their spatial distributions. Also, array cancelers are inadequate when the signals are less than an array beamwidth apart. The latter was dealt with using supperesolution and eigenanalysis methods. Different time domain methods were used in the past. Among them what is termed Cross-Coupled PEL. It is an arrangement of two PLL each one is locked on and tracking one …

Fault Tolerant Clos Network, Preet Mohan S. Ahluwalia

Theses

Multistage interconnection networks, or MINs, provide paths between functional modules in multiprocessor systems. The MINs are usually segmented into several stages. Each stage connects inputs to appropriate links of the next stage so that the cumulative effect of all the stages satisfies input-output connection requirements.

This thesis deals with a fault tolerant Clos network. The fault tolerance technique involves addition of extra switches per stage to compensate for any switch failure The reliability analysis of both ordinary and fault tolerant Clos networks is presented. The optimal number of extra switches required to get the best reliability results has been analyzed.