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Clustering Algorithm For Local Area Network Design In A Cim Environment, A. C. Manjunath May 1992

Clustering Algorithm For Local Area Network Design In A Cim Environment, A. C. Manjunath

Theses

Communication systems have come to be regarded as being one of the most important aspects in manufacturing enterprises in recent years. It continues to offer enormous potential for improving the efficiency of manufacturing enterprises through Computer Integrated Manufacturing (CIM). It is true however that this potential cannot be realized by developments on the communications front alone. Strategic and economic considerations in installing a communications system in a manufacturing environment is of vital significance.

This thesis, at the outset attempts to bring out some of the issues in the area of communications (research), specifically in relation to CIM. A perception of …


Ultrasonic Ranging System For Gait Analysis, Mu Wu May 1992

Ultrasonic Ranging System For Gait Analysis, Mu Wu

Theses

A new method of measuring range for gait analysis is described. The method is based on a coherent measurement of the phase shift of an ultrasonic signal as a function of range.

A prototype of the ranging system was breadboarded, tested, and found to have a relative accuracy of better than 0.5 mm over a range of 3 meters. The maximum range the system is at least 20 meters. The method used here is new and has not been found in the literature. Tt is demonstrated by experiments with a prototype system that can measure distance with a higher accuracy …


Pure Strong Competition For Two Microbial Populations In A Chemostat, Efthimios Ioannis Banias May 1992

Pure Strong Competition For Two Microbial Populations In A Chemostat, Efthimios Ioannis Banias

Theses

The dynamics of pure, strong, double competition between two microbial populations in an ideal chemostat have been investigated by using mathematical and numerical analysis. The two nutrients competed for have been assumed to be complementary for both competitors. Inter active models have been used for the specific growth rates. Two cases have been considered; one in which neither of the two substrates exerts inhibitory effects on the growth of either one of the competing populations, and one in which the growth of one population is inhibited by only one of the two substrates. The primary focus of this investigation was …


Inability Of Phanerochaete Chrysosporium To Degrade Polychlorinated Biphenyls In Sand, Pankaj Pankaj May 1992

Inability Of Phanerochaete Chrysosporium To Degrade Polychlorinated Biphenyls In Sand, Pankaj Pankaj

Theses

The white rot fungus Phanerochaete chrysosporium has been previously found to successfully degrade a wide spectrum of chlorinated aromatic hydrocarbons (some of them in soil or sand matrices). In this research, it was tested if the fungus could also degrade a very recalcitrant class of pollutant, i.e. Polychlorinated Biphenyls (PCBs) in sand at a concentration of 100 ppm (w/w PCB to sand). For this purpose, a number of experiments were performed, in which several operating parameters, such as nutrient concentrations (nitrogen and glucose), amount of initial biomass, aeration, and degree of chlorination of the PCBs were varied. The results obtained …


The Effects Of Twist On Pressure Through A Teflon Vascular Prosthesis, Steven Alfred Olivieri May 1992

The Effects Of Twist On Pressure Through A Teflon Vascular Prosthesis, Steven Alfred Olivieri

Theses

A closed loop fluid system was developed which mimics the flow curve in the human circulatory system in order to test the effects of pressure drop and flow velocity on artificial arterial implants. This device consists of a piston pump connected to a microcomputer controlled servo-motor. Fluid (in this case distilled water) flows through transparent Tygon tubing to a test chamber. The prosthetic tube is placed in the fluid but is attached through a specially constructed chamber. The pressure across the implant can be measured for different conditions. System compliance was generated by using flexible tubing in the return loop …


An Embedded Controller-Based Fiber Optic Sensor For Use In Fresh Concrete, Zhaowu Zhang May 1992

An Embedded Controller-Based Fiber Optic Sensor For Use In Fresh Concrete, Zhaowu Zhang

Theses

The principle of refraction and reflection of light in optical fibers is applied to detection of air bubbles in a previous thesis. In the earlier work, a microcomputer was employed in acquisition and processing of air bubble data. In the present thesis, an embedded controller system is interfaced and programmed in order to replace the microcomputer. In this way, the system can be more easily integrated into field construction operations. Reflected light intensity signals are detected and analyzed by a microcontroller. The entrained percentage of air in concrete is displayed immediately. The signal can be transferred through a UART (Universal …


Kinetic Measuremenmt Of Decomposition Of Aniline, 2,4-Dichlorophenol And 1,2,4-Trichlorophenol Using A Calorimetric Method, Ming-Chin Chang May 1992

Kinetic Measuremenmt Of Decomposition Of Aniline, 2,4-Dichlorophenol And 1,2,4-Trichlorophenol Using A Calorimetric Method, Ming-Chin Chang

Theses

Biological treatment techniques for detoxification of toxic organic compounds have been studied and applied for many years. There are many research and commercial applications proving that the biological method is more economic and efficient than the other treatment methods.

The traditional biomass measurements are time-consuming tasks. Researchers have intended to develop a simpler, faster, and also accurate method for determining the bioactivity. This study has tried to use the microcalorimetric method to monitor the energy productions from the degradation of aniline, 2,4-Dichlorophenol and 1,2,4-Trichlorobenzene. Thereafter, by utilizing the data obtained from the present study, it was possible to compute kinetic …


Computational Aspects Of A Three Dimensional Non-Intrusive Particle Motion Tracking System, Avadhani S. Ashok May 1992

Computational Aspects Of A Three Dimensional Non-Intrusive Particle Motion Tracking System, Avadhani S. Ashok

Theses

Development of a technique for non-intrusive particle motion tracking in three dimensions is considered. This technique is based on the principle of magnetic induction. In particular, the determination of the position and onentation of the particle from the information gathered is the pnncipal focus of this thesis. The development of such a system is motivated by the need to understand the flow patterns of granular material. This is of cntical importance in dealing with problems associated with bulk solids flows which occur in almost all industries and in natural geological events. A study of the current diagnostic techniques reveals the …


Acuta Enews May 1992, Vol. 21, No. 5 May 1992

Acuta Enews May 1992, Vol. 21, No. 5

ACUTA Newsletters

In This Issue

Nominations for officers sought

President's column

AT&T opens development site

Northeast regional meeting


Review: 'Optical Fiber Communications' (2nd Edition), By Gerd Keiser, Bradley D. Duncan May 1992

Review: 'Optical Fiber Communications' (2nd Edition), By Gerd Keiser, Bradley D. Duncan

Electro-Optics and Photonics Faculty Publications

If first impressions are worth anything (and they usually are), I would have to admit that my first impression of the second edition of Gerd Keiser's now popular text Optical Fiber Communications was quite good. My compliments are hereby extended to the publisher for choosing a rather handsome cover and dust jacket. It stands in strong contrast to the text's first edition, which still ranks as probably the ugliest book I own, with color choices ranging from dull cream and "baby" blue to pale pink! I am now happy to say that this older version has been discretely·retired to the …


Bs News May 1992

Bs News

Building Services Engineering

No abstract provided.


An Investigation Into The Engineering Considerations Required To Design An Ultra Low Noise Logarithmic Amplifier For An Ultrasound Imaging System, Michael Wilhelm Apr 1992

An Investigation Into The Engineering Considerations Required To Design An Ultra Low Noise Logarithmic Amplifier For An Ultrasound Imaging System, Michael Wilhelm

Opportunities for Undergraduate Research Experience Program (OURE)

Ultrasound imaging instruments and other "radar" type systems frequently employ variable gain amplifiers to effectively process signals of high dynamic range. One such device uniquely suited for this task is the logarithmic amplifier. Presented in this paper are many of the key design issues and solutions concerning the enhancement of one particular company's ultrasound system.


Santa Clara Magazine, Volume 34 Number 3, Spring 1992, Santa Clara University Apr 1992

Santa Clara Magazine, Volume 34 Number 3, Spring 1992, Santa Clara University

Santa Clara Magazine

12 - EAST L.A. STORY Jesuit-run Dolores Mission Alternative School is a last chance for East L.A.'s troubled teen-agers, many of whom are members of violent Latino gangs. By Rene Romo '86

20 - ONE IS TOO MANY TWO ARE NOT ENOUGH A personal account of one woman's struggle with alcohol addiction. By Lisa Agrimonti '87

24 - UP CLOSE: WITOLD KRASSOWSKI After five years in the Polish Underground Army during WW II, the founder of SCU's Sociology Department came to America and discovered teaching. His 40-year commitment to students has never waivered. By Christine Spielberger '69

28 - WORKING …


Spring 1992, Wmpg 90.9 Fm Apr 1992

Spring 1992, Wmpg 90.9 Fm

WMPG Program Guides

WMPG program guide for Spring 1992

Includes notes from Program Director, information on shows and events, and schedule.


Bulletin - Spring, 1992, Civil Aviation Medical Association Apr 1992

Bulletin - Spring, 1992, Civil Aviation Medical Association

Browse all Civil Aviation Medical Association Newsletters

A twelve page newsletter of the Civil Aviation Medical Association. The newsletter provided news about civil aviation medicine and information related to the organization.


A General Three Dimensional All Quadrilateral Surface Mesh Generation Algorithm, Roger Cass Apr 1992

A General Three Dimensional All Quadrilateral Surface Mesh Generation Algorithm, Roger Cass

Theses and Dissertations

Among the available all-quadrilateral mesh generation algorithms progressive-front offers the best quality and robustness. The paving algorithm is a progressive-front technique that generates a two dimensional mesh of all quadrilaterals on planar surfaces. The technique is particularly suited to meshing irregular boundaries with interior holes. This thesis presents an extension of the paving algorithm to generalized three dimensional surfaces. The major problems in three-dimensional surface mesh generation are projection of nodes, calculation of interior angles, and connection of mesh fronts. The solutions to these problems are presented. This work is part of the ongoing CUBIT project at Sandia Labs. The …


The Calendar - April 1992, Nova University Apr 1992

The Calendar - April 1992, Nova University

The Calendar

No abstract provided.


Optimization Of Cryopreservation Protocols For Cardiovascular Tissue, Jianfei Hu Apr 1992

Optimization Of Cryopreservation Protocols For Cardiovascular Tissue, Jianfei Hu

Theses and Dissertations in Biomedical Sciences

The purpose of this research was to determine the effects of cryopreservation on the physical, biochemical and cellular aspects of heart valve tissue. The present study demonstrated that radiolabeled proline accumulation provides a quantitative estimate of total cellular metabolic viability. Radiolabeled inulin was demonstrated to be a useful marker for extracellular tissue space. Assessment of metabolic viability of the cellular population of leaflet tissue as a function of procurement and processing revealed that proline accumulation declined with increasing warm and cold ischemic times. Amphotericin B and streptomycin were toxic to the cells. Cefoxitin, lincomycin, polymyxin B, vancomycin and penicillin had …


Modal Analysis Of Gyroscopically Coupled Sound-Structure Interaction Problems, Vijay B. Bokil Apr 1992

Modal Analysis Of Gyroscopically Coupled Sound-Structure Interaction Problems, Vijay B. Bokil

Mechanical & Aerospace Engineering Theses & Dissertations

In many practical situations we encounter sound-structure interaction between the fluid in a cavity and the flexible wall on the boundary. The aircraft cabin interacting with its fuselage and double-leaf partition walls interacting with the enclosed cavity are some of the typical examples. The vibratory behavior of the structure and the acoustical pressure inside the cavity are affected by this interaction.

In most of the cases, the governing differential equations for the coupled system can be shown to involve gyroscopic coupling. A special method has been applied to decouple the equations in terms of pairs of generalized coordinates and the …


Bs News Apr 1992

Bs News

Building Services Engineering

No abstract provided.


The Calendar - March 1992, Nova University Mar 1992

The Calendar - March 1992, Nova University

The Calendar

No abstract provided.


Exponential Characteristic Spatial Quadrature For Discrete Ordinates Neutral Particle Transport In Slab Geometry, Glenn E. Sjoden Mar 1992

Exponential Characteristic Spatial Quadrature For Discrete Ordinates Neutral Particle Transport In Slab Geometry, Glenn E. Sjoden

Theses and Dissertations

A new discrete ordinates spatial quadrature scheme is presented for solving neutral particle transport problems. This new scheme, called the exponential characteristic method, is developed here in slab geometry with isotropic scattering. This method uses a characteristic integration of the Boltzmann transport equation with an exponential function as the assumed from of the source distribution, continuous across each spatial cell. The exponential source function is constructed to globally conserve zeroth and first spatial source moments and is non-negative. Characteristic integration ensures non- negative fluxes and flux moments. Numerical testing indicates that convergence of the exponential characteristic scheme is fourth order …


An Examination Of The Feasibility Of A Nuclear-Pumped Laser-Driven Inertial Confinement Fusion Reactor With Magnetically Protected Walls, John M. Jacobson Mar 1992

An Examination Of The Feasibility Of A Nuclear-Pumped Laser-Driven Inertial Confinement Fusion Reactor With Magnetically Protected Walls, John M. Jacobson

Theses and Dissertations

A preliminary design study of a nuclear-pumped laser-driven inertial confinement fusion reactor with a magnetically protected first wall using an advanced DT-ignited, DD-fueled pellet demonstrated the feasibility of such a concept. This paper presents a parametric study of the required energy multiplication in the blanket, the pellet injection rate, and the net efficiency of this is conceptual reactor for advanced pellet yields. A model of the reactor energy balance yields a required energy multiplication of 2.4. A cylindrical design for a helium-cooled blanket demonstrates that natural uranium micropellets in a laser pump region provide a multiplication of 2.9 with a …


Design And Construction Of A Channel Electron Multiplier Based Mossbauer Spectroscopy System, Daniel J. Robbins Mar 1992

Design And Construction Of A Channel Electron Multiplier Based Mossbauer Spectroscopy System, Daniel J. Robbins

Theses and Dissertations

A channel electron multiplier (cem) detector system was designed and built to provide a signal to a Mossbauer spectroscopy system in an effort to obtain a better signal-to-noise ratio than achievable with a proportional counter system. Three cems are contained in a vacuum chamber built using standard components. Gamma, rays of 14.4-keV energy from a 57Co source enter from outside the chamber through a window and are absorbed by an 57Fe target near the cems. The target emits internal conversion electrons which are collected by the cems and a Mossbauer spectrometer collects the signal. The system produces a …


Effects Of Facility Configurations And Scheduling Techniques On Aircraft Throughput For Warner Robins Alc Paint/Depaint Facilities, David V. Mcelveen Mar 1992

Effects Of Facility Configurations And Scheduling Techniques On Aircraft Throughput For Warner Robins Alc Paint/Depaint Facilities, David V. Mcelveen

Theses and Dissertations

The purpose of this research was to determine the effects of configuration options and dispatching rules on aircraft throughput for the WR- ALC paint/depaint facilities. A simulation model was constructed and used for this analysis as the primary means to conduct the research. The dispatching rules considered were first come first served, largest number in queue, shortest processing time, and a look ahead heuristic. Due to a reduction in the number of paint aircraft, no configuration option differing from the baseline significantly affected aircraft throughput. Dispatching rules were also found to produce no significant differences on aircraft throughput. Configuration options …


Quantifying The Impact Of The Acquisition Professional Development Program Certification Requirements On The Air Force Institute Of Technology, Paul A. Nicholson Mar 1992

Quantifying The Impact Of The Acquisition Professional Development Program Certification Requirements On The Air Force Institute Of Technology, Paul A. Nicholson

Theses and Dissertations

The purpose of this research is to determine the impact of implementing the Acquisition Professional Development Program on the Air Force Institute of Technology. APDP is part of a DOD-wide effort to decrease inefficiency in the procurement process. The program encompasses a tri-level certification process based on experience, training, and educational standards. APDP serves as a guideline for professional development of acquisition personnel from entry to senior level management. Many of the courses required for certification are offered through AFIT School of Systems and Logistics. Integrating the new educational requirements as a standard for career development is expected to produce …


Achieving A Given Reflectance For Unpolarized Light By Controlling The Incidence Angle And The Thickness Of A Transparent Thin Film On An Absorbing Substrate: Application To Energy Equipartition In The Four-Detector Photopolarimeter, R. M.A. Azzam, Kurt A. Giardina Mar 1992

Achieving A Given Reflectance For Unpolarized Light By Controlling The Incidence Angle And The Thickness Of A Transparent Thin Film On An Absorbing Substrate: Application To Energy Equipartition In The Four-Detector Photopolarimeter, R. M.A. Azzam, Kurt A. Giardina

Electrical Engineering Faculty Publications

At a given wavelength λ we determine all possible solution pairs (ϕ, ζ) of the incidence angle ϕ and the thickness ζ of a transparent thin film on an absorbing substrate that achieve a given unpolarized light reflectance Ru. The trajectory of the point that represents a solution pair in the ζ, ϕ plane depends on the optical properties of the film and substrate and on whether Ru is greater than or less than the normal-incidence reflectance -R0 of the bare substrate. When Ru > - R0, the specified reflectance is achieved over a …


Network Analysis Of Intermediary Metabolism Using Linear Optimization. Ii. Interpretation Of Hybridoma Cell Metabolism, Joanne M. Savinell (Belovich), Bernhard O. Palsson Feb 1992

Network Analysis Of Intermediary Metabolism Using Linear Optimization. Ii. Interpretation Of Hybridoma Cell Metabolism, Joanne M. Savinell (Belovich), Bernhard O. Palsson

Chemical & Biomedical Engineering Faculty Publications

Analysis of metabolic networks using linear optimization theory allows one to quantify and understand the limitations imposed on the cell by its metabolic stoichiometry, and to understand how the flux through each pathway influences the overall behavior of metabolism. A stoichiometric matrix accounting for the major pathways involved in energy and mass transformations in the cell was used in our analysis. The auxiliary parameters of linear optimization, the so-called shadow prices, identify the intermediates and cofactors that cause the growth to be limited on each nutrient. This formalism was used to examine how well the cell balances its needs for …


Acuta Enews February 1992, Vol. 21, No. 2 Feb 1992

Acuta Enews February 1992, Vol. 21, No. 2

ACUTA Newsletters

In This Issue

Call for RD Nominations

President's column

Workshop announcement

Alabama college takes case to PSC

Party Line

Rating to Tucson seminars


Effect Of Co2 On The Processing Of Y-Ba-Cu-O Superconductors, C. Zhang, Guna S. Selvaduray Feb 1992

Effect Of Co2 On The Processing Of Y-Ba-Cu-O Superconductors, C. Zhang, Guna S. Selvaduray

Faculty Publications

The superconducting properties of YBa2Cu3O6+x reacted with various known ratios of O2/CO2 gas mixtures during sintering at different temperatures were studied. Jc was found to decrease drastically upon reaction with CO2, becoming zero at certain CO2 activities. The stability region for the 123 superconductor, as a function of CO2 activity and temperature, was empirically formulated as follows: log pCO2 < (−45,000)/T + 33.4. The grain boundaries in sintered samples with Jc = 0 were investigated with HRTEM in conjunction with EDS. Two distinct types of grain boundaries were observed. Approximately 10% of the grain boundaries were wet by a thin layer of a second phase, deduced to be BaCuO2. The remaining boundaries were sharp grain boundaries. The grain structure near the sharp grain boundaries was tetragonal. These two types of grain boundaries are thought to be responsible for Jc being zero.