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The Calendar - October 1990, Nova University Oct 1990

The Calendar - October 1990, Nova University

The Calendar

No abstract provided.


Santa Clara Magazine, Volume 33 Number 1, Fall 1990, Santa Clara University Oct 1990

Santa Clara Magazine, Volume 33 Number 1, Fall 1990, Santa Clara University

Santa Clara Magazine

12 - PRIESTS & MARRIAGE The Pope has allowed the ordination of nearly 50 married Episcopal priests since 1980. Some see this as a sign of hope for a married priesthood . By Julie Sly '82

18 - THE POWER OF ONE Because of her own personal tragedy, Mary Beth Cahill Phillips '76 forced the state of California to form Trustline, a registry parents can use to check out a nanny. By Susan Frey

20 - THE ART OF BIOGRAPHY Our natural curiosity about each other tempts us into reading biographies the same way we turn to novels. Is peering …


Integrated Control Of Thermally Distorted Large Space Antennas, Robert H. Tolson Oct 1990

Integrated Control Of Thermally Distorted Large Space Antennas, Robert H. Tolson

Mechanical & Aerospace Engineering Theses & Dissertations

Studies on controlling the thermal distortion of large space antennae have generally investigated a single orbital position and have optimized actuator locations based on minimizing the RMS surface deviation from the original parabolic shape. One study showed the benefits of directly using far zone electric field characteristics as the performance measure; but, this approach resulted in a nonlinear programming problem. The objective of the current study is to develop an approach to designing a control system that (1) recognizes the time dependence of the distortion and (2) controls variables that are directly related to far field performance in a quadratic …


Space Structures: Issues In Dynamics And Control, H. Benaroya, Mark L. Nagurka Oct 1990

Space Structures: Issues In Dynamics And Control, H. Benaroya, Mark L. Nagurka

Mechanical Engineering Faculty Research and Publications

A selective technical overview is presented on the vibration and control of large space structures, the analysis, design, and construction of which will require major technical contributions from the civil/structural, mechanical, and extended engineering communities. The immediacy of the U.S. space station makes the particular emphasis placed on large space structures and their control appropriate. The space station is but one part of the space program, and includes the lunar base, which the space station is to service. This paper attempts to summarize some of the key technical issues and hence provide a starting point for further involvement. The first …


A Software Design Tool For Predictable Performance In Real-Time, Data Flow Architectures, Brij Mohan V. Mandala Oct 1990

A Software Design Tool For Predictable Performance In Real-Time, Data Flow Architectures, Brij Mohan V. Mandala

Electrical & Computer Engineering Theses & Dissertations

A software design tool which aids in the performance evaluation and selection of operating points for an algorithm implemented in ATAMM defined data flow architectures is presented in this thesis. ATAMM (Algorithm To Architecture Mapping Model) is a new graph theoretic model developed by researchers at Old Dominion University and the NASA-Langley Research Center. ATAMM is capable of modeling the execution of large-grained algorithms on distributed data flow architectures. A software tool is required for predicting the performance, determining the resource requirements and for selecting suitable operating points for an ATAMM based system. The ATAMM Design Tool presented in this …


Deep Level Characterization Studies In Gaas, Gordhan R. Barevadia Oct 1990

Deep Level Characterization Studies In Gaas, Gordhan R. Barevadia

Electrical & Computer Engineering Theses & Dissertations

The goal of this research was to investigate deep levels in different types of GaAs, a material for high power optically controlled bulk semiconductor switches. For low resistivity semiconductors, such as silicon doped GaAs material (p =0.054 Ω cm), deep level transient spectroscopy (DLTS) was used to characterize deep levels. Three deep levels (EL6, EL3, and EL2) have been detected in this material. For high resistivity semiconductors (p > 104 Ω cm), difficulty of electrical carrier injection and of making a junction does not permit the use of DLTS technique. Therefore, an experimental set-up of the photo-induced current transient spectroscopy …


Implementation Of Parallel Sorting Algorithms On A Transputer Network, Venkatraman U. Calidas Sep 1990

Implementation Of Parallel Sorting Algorithms On A Transputer Network, Venkatraman U. Calidas

Theses

Many sorting algorithms, such as the bubble sort and the binary tree selection sort, are n-squared algorithms and take O (n2) time to sort n values. These can be easily parallelized; the resulting sorts are called the odd-even transposition sort and the parallel tree selection sort, respectively. These have O(nlogn) time complexity. The quicksort is an O(nlogn) algorithm and it can parallelized to make it an O(logn) algorithm.

A transputer is a microprocessor which has serial links to transmit and receive data from other transputers. The above algorithms are implemented on a network of transputers and the link connections for …


Simulation And Analysis Of Priority Classes In Extended Token Based Local Area Networks, Bhavinkumar R. Pathak Sep 1990

Simulation And Analysis Of Priority Classes In Extended Token Based Local Area Networks, Bhavinkumar R. Pathak

Theses

Recently, Local Area Networks carrying multiple priority classes of messages have received considerable attention. The IEEE 802.5 token ring standard defines an optional priority scheme to handle different priority classes of messages. A simulation model of symmetric priority based networks, consisting of token ring networks interconnected by a bridge is considered. Messages are divided into two priority classes, namely, high priority traffic and low priority traffic. High priority traffic is guaranteed access on the channel, whereas low priority messages are served when the system determines that no high priority messages are currently waiting. The simulation results are used to evaluate …


Microcomputer-Based Visual Controller And Data Logger System, Xiao-Fang Qi Sep 1990

Microcomputer-Based Visual Controller And Data Logger System, Xiao-Fang Qi

Theses

This thesis paper describes the firmware design, instead of the hardware logic design, makes the machine vision hardware system economical, intelligent and expandable. It shows the construction and testing of a novel remote low speed machine vision control system, which also has functions as data logger and is capable of auto control. The system has 9 analog input channels available, and more. It also has 4 digital output channels for controlling external devices. This work also implemented a way to transfer the grabbed image to a PC/XT. In the 256 graphics mode of the VGA, 64 B&W gray levels can …


The Interconnection Network Analysis Package, Nadeem Sabbar Sep 1990

The Interconnection Network Analysis Package, Nadeem Sabbar

Theses

This thesis focuses on the development of the Interconnection Network Analysis Package (INAP), and the use of INAP to analyze minimal permutation networks. The INAP code is written in C language using Turbo C compiler. Although the INAP has been used to analyze the subject networks it is not a dedicated system. It gives the user the freedom to create the permutation network from scratch (1-8 inputs and 1-7 stages), and then to process it for any number of stages.

The INAP made the analysis of five input networks easy and efficient. The networks have been analyzed stage by stage. …


Simulation And Analysis Of Integrated Lans For Hospital Environment, Naveen K. Verma Sep 1990

Simulation And Analysis Of Integrated Lans For Hospital Environment, Naveen K. Verma

Theses

Hospitals generate a large number of data sets of different types and formats and it is required to integrate these data sets for their rapid and simultaneous communication in order for a better treatment of patients and to cut the escalating costs. A better approach to meet this requirement is to have a distributed system linked all together with a high capacity LAN using an efficient integration method.

This thesis begins by studying the characteristic feature and suitability of Queued Packet & Synchronous Exchange (QPSX) network architecture. The network models are simulated for QPSX, Ethernet and Token Bus networks for …


Neural Net Classification Of States In Finite State Vector Quantization, Zhigang Zhang Sep 1990

Neural Net Classification Of States In Finite State Vector Quantization, Zhigang Zhang

Theses

In this thesis, a new image coding technique based on Neural Network Finite State Vector Quantization(NNFSVQ) is presented. The new design takes advantage of the high interblock spatial correlation of pixels in typical grey-level images, in addition to intrablock correlation already exploited by vector quantization (VQ). Although many FSVQ require large memory space for the storage of the numerous state codebooks, the memory space requirement of NNFSVQ can be reduced by a very large factor (about 102-103) to manageable size without impairing image quality. Simulation experiments have shown that by using NNFSVQ the bit rate can …


Optimization Of Bandwidth Allocation In Atm Nets Through Simulated Annealing, Chien-Long Hou Sep 1990

Optimization Of Bandwidth Allocation In Atm Nets Through Simulated Annealing, Chien-Long Hou

Theses

Optimization of Bandwidth Allocation in ATM network is considered in this thesis. We address the problem of determining optimal bandwidth allocation in such BISDN's that adopt ATM as their basic switching. technique by using Simulated Annealing. Computer simulation shows that this optimal policy leads to the configuration which yields the minimum average packet delay.


An Optically Powered Cmos On-Chip Power Supply, Jaeyong Jeong Sep 1990

An Optically Powered Cmos On-Chip Power Supply, Jaeyong Jeong

Theses

This thesis presents an optically powered CMOS on-chip power supply for CMOS IC applications. There exists a need for specialized chips that are located remotely and are powered by light supplied through fiber-optic cabling. An optically powered CMOS on-chip power supply circuit described in this thesis is composed of three subcircuits; light to voltage converter circuit, clock pulse generator circuit, and voltage multiplier circuit. Each subcircuit has been analyzed and designed, and simmulated using SPICE 2G.5/6 with 3pm CMOS SPICE parameters from the MOSIS. The circuits layout has been done using MAGIC according to the MOSIS scalable CMOS design rules. …


A Transputer Based Distributed Graphics Display, Ramana V. Kattula Sep 1990

A Transputer Based Distributed Graphics Display, Ramana V. Kattula

Theses

The design of a transputer based graphics display is discussed. The problems associated with the single processor graphics systems are described. A solution based on multiple transputers is proposed. The transputer based graphics display described is a general purpose graphics system which can achieve any required compute performance and drawing performance without using special hardware. The display resolution and color depth can be enhanced as per the user requirements with little or no change in hardware.


Landmark-Based Shape Recognition By A Modified Hopfield Neural Network, Kuowei Li Sep 1990

Landmark-Based Shape Recognition By A Modified Hopfield Neural Network, Kuowei Li

Theses

In this thesis, we introduce a new thethod to achieve partial shape recognition by means of a modified Hopfield neural network. To recognize partially visible object, we represent each object by a set of "landmarks." The landmarks of an object are points of interest relative to the object that have important shape attributes. Given a scene consisting of partially occluded objects, a model object in the scene is hypothesized by matching the landmarks of the model with those in the scene. A measure of similarity between two landmarks, one from a model and the other from the scene, is needed …


A Quantization Noise Feedback Technique In Pyramid Image Coding, Zhili Lin Sep 1990

A Quantization Noise Feedback Technique In Pyramid Image Coding, Zhili Lin

Theses

In communication, we frequently encounter the problem about the trans-mission rate and quantization noise. That is, small quantization noise or high fidelity definitely increases transmission rate, or large quantization noise or low fidelity might require low transmission rate. In our research, we developed a quantization noise feedback technique, with which quantization noise can be reduced greatly at a given transmission rate. We applied this technique in pyramid image coding environment. An error analysis in frequency domain was carried out. Error estimation for pyramid image coding with and without quantization noise feedback was made. Finally, plenty of computer simulation confirms our …


Decomposing Non-Product Form Queuing Lattices Through Simulated Annealing, Jr-Chin Lin Sep 1990

Decomposing Non-Product Form Queuing Lattices Through Simulated Annealing, Jr-Chin Lin

Theses

A random, heuristic search called Simulated Annealing is adapted to decompose the state transition lattice of Non-Product Form Queuing Models. Simulated Annealing Algorithm has been successfully applied to a number of optimization problem such as The Traveling Salesman Problem, Graph Partionning, Physical Computer Design, VLSI Chip Design, Image Processing,... etc. It has the advantage over other gradient descent techniques to solve the combinatorial problems. The solution can escape from local minimum by adding Boltzmann Distribution Factor to the algorithm. Most lattice of non-product form queuing models can be decomposed into Solvable Subsets through this algorithm, and solvable subset is the …


Max/Min : A Novel Rank Order Based Filter Family, Raafat E. Kamel Sep 1990

Max/Min : A Novel Rank Order Based Filter Family, Raafat E. Kamel

Theses

In the early development of signal and image processing, linear filters were the primary tools. Their mathematical simplicity made them easy to design and implement. They also offered satisfactory performance in many applications. However, they show poor performance in other cases, such as image processing.

Nonlinear filtering offered a solution to these problems. Nonlinear filtering has undergone a lot development for a long time. Among the first known nonlinear filters was the median filter, which was proposed by Tukey. Median filter preserves signal or image details better compared to a linear filter. Later other nonlinear filters were developed, including median …


Relative And Absolute Timing Jitter In Actively Mode-Locked Semiconductor Lasers, Dennis J. Derickson, A. Mar, J. E. Bowers Sep 1990

Relative And Absolute Timing Jitter In Actively Mode-Locked Semiconductor Lasers, Dennis J. Derickson, A. Mar, J. E. Bowers

Electrical Engineering

No abstract provided.


Acuta Enews September 1990, Vol. 19, No. 9 Sep 1990

Acuta Enews September 1990, Vol. 19, No. 9

ACUTA Newsletters

In This Issue

Are colleges aggregators?

President's column

Four workshops scheduled

Revising the directory

A six-node network

Update on Portland


Perceived Risks Versus Actual Risks: Managing Hazards Through Negotiation, Kristin S. Shrader-Frechette Sep 1990

Perceived Risks Versus Actual Risks: Managing Hazards Through Negotiation, Kristin S. Shrader-Frechette

RISK: Health, Safety & Environment (1990-2002)

The author describes what she calls the "Expert-Judgment Strategy", finding that, because it discounts lay perceptions of Risk, it interferes with the acceptance of important but Risky technologies.


Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, September 1990, College Of Engineering And Computer Science, Wright State University Sep 1990

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, September 1990, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

An eight page newsletter created by the Wright State University College of Engineering and Computer Science that addresses the current affairs of the college.


On The Maximum Range Of Flying Wings, Peter J. Torvik Sep 1990

On The Maximum Range Of Flying Wings, Peter J. Torvik

AFIT Documents

The classical equations for determining the maximum range of aircraft with propeller and jet propulsion systems are reviewed, along with previous work conducted to determine the optimal division of aircraft volume between fuselage and wing components. That the jet powered flying wing configuration produces optimal range only for limited geometries is confirmed. The optimal range of aircraft employing high bypass jet engines is explored, and found to lead to a broader range of design parameters for which the flying wing design produces maximum range than is the case when a pure jet system is used.


The Role Of Scientists In Risk Assessment, Halina Szejwald Brown, Robert L. Goble Sep 1990

The Role Of Scientists In Risk Assessment, Halina Szejwald Brown, Robert L. Goble

RISK: Health, Safety & Environment (1990-2002)

The authors argue that Risk assessors belong to a profession and offer an alternative to the 1983 National Research Council model defining Risk assessment. They support and illustrate their model by reexamining three familiar Risk assessments: ethylene dibromide, WASH 1400, and Ice Minus Bacteria.


Optimized Cross Correlation Waveforms For First Order Correlation Loops, Kurt Louis Kosbar Sep 1990

Optimized Cross Correlation Waveforms For First Order Correlation Loops, Kurt Louis Kosbar

Electrical and Computer Engineering Faculty Research & Creative Works

In this work, the steady state mean square tracking error of first order correlation loops is minimized by varying the locally generated cross correlation function produced by the voltage controlled oscillator. This analysis should assist in the design of modified first order delay locked loops used for pseudonoise code synchronization in direct sequence spread spectrum receivers. The optimum cross correlation waveform is generated by filtering a replica of the originally transmitted signal. The optimal filter imposes a 90 degree phase shift at all frequencies and has an amplitude response that is a function of the channel signal to noise ratio. …


Irish Building Services News Sep 1990

Irish Building Services News

Building Services Engineering

No abstract provided.


Comparative Analysis Of Single And Double Dwell Acquisition Schemes, Gurinder Singh Ahluwalia Aug 1990

Comparative Analysis Of Single And Double Dwell Acquisition Schemes, Gurinder Singh Ahluwalia

Theses

Single and double dwell pseudonoise (PN) acquisition systems are described, explained and analyzed. These systems are designed to synchronize a locally generated PN signal with a received PN signal of unknown phase in the presence of noise. The mean, variance and an approximate probability distribution function (PDF) of the acquisition time for the single and double dwell PN acquisition schemes is developed. Intuitively, the double dwell acquisition system should be superior to the single dwell system because of the ability to quickly dismiss incorrect cells and further verify probable hits. It is shown analytically that this is in fact true …


Decomposing Non-Product Form Queuing Lattices Through Genetic Algorithm, Wei Han Aug 1990

Decomposing Non-Product Form Queuing Lattices Through Genetic Algorithm, Wei Han

Theses

In this paper, a Genetic Algorithm technique is adapted to decompose the state transition lattice of a class of non-product form queueing models. Genetic Algorithms are search algorithms based upon the mechanics of natural genetics. They combine a survival-of-the-fittest among string structures with a structured, yet randomized, information exchange to form a search algorithm with some of the innovative flair of human search. While randomized, genetic algorithms are no simple random walk. They efficiently exploit historical information to speculate on new search points with improved performance. Here genetic algorithms is applied to a non-product queueing lattices optimization problem. Only the …


Performance Evaluation Of Consumer Electronic Bus, Sairaj R. Pakkam Aug 1990

Performance Evaluation Of Consumer Electronic Bus, Sairaj R. Pakkam

Theses

This thesis describes the performance evaluation of the Consumer Electronic Bus proposed by the Electronic Industries Association. To study the behaviour of CEBUS under different traffic conditions, a simulation program was developed modelling the layer architecture of CEBUS. The CEBUS is based on the ISO/OSI model of layered architecture. The simulation results have shown that, when the throughput of the network is small, the delay is bounded for all messages of all priorities. As the throughput of the network increases, under the presence of more high priority messages, the lower priority messages get queued at their nodes. It is also …