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Investigation Of Radiative Interactions In Supersonic Chemically Reacting Channel Flows, Almuttil M. Thomas Jul 1991

Investigation Of Radiative Interactions In Supersonic Chemically Reacting Channel Flows, Almuttil M. Thomas

Mechanical & Aerospace Engineering Theses & Dissertations

Analyses and numerical procedures are presented to investigate the radiative interactions of absorbing emitting species in chemically reacting supersonic flow in various ducts. The two-dimensional time dependent Navier-Stokes equations in conjunction with radiative flux equation are used to investigate supersonic flows undergoing finite rate chemical reaction in a hydrogen air system. The specific problem considered is the flow of premixed radiating gas between parallel plates. Specific attention is directed in investigating the radiative contribution of H2O, OH and NO under realistic physical and flow conditions. Results are presented for the radiative flux obtained for different gases and for various combination …


On Shock Capturing For Liquid And Gas Media, Tze Jang Chen Jul 1991

On Shock Capturing For Liquid And Gas Media, Tze Jang Chen

Mathematics & Statistics Theses & Dissertations

The numerical investigation of shock phenomena in gas or liquid media where a specifying relation for internal energy is absent poses special problems. Classically, for gas dynamics the usual procedure is to employ a splitting scheme to remove the source terms from the Euler equations, then up-wind biased shock capturing algorithms are built around the Riemann problem for the system which remains. However, in the case where the Euler equations are formulated in the term of total enthalpy, a technical difficulty associated with equation splitting forces a pressure time derivative to be treated as a source term. This makes it …


Simulation And Measurement Of The Radiant Field Produced By Quartz Heating Systems, Travis Lee Turner Jul 1991

Simulation And Measurement Of The Radiant Field Produced By Quartz Heating Systems, Travis Lee Turner

Mechanical & Aerospace Engineering Theses & Dissertations

A method is developed for predicting the radiant heat flux distribution produced by tungsten-filament tubular quartz heating systems with reflectors. The method is an application of Monte Carlo simulation, which takes the form of a ray tracing or random walk scheme. The method is applied to four systems of increasing complexity including; a single unreflected lamp, a single lamp with a flat reflector, a single lamp with a parabolic reflector, and up to six lamps in a six-lamp contoured reflector heating unit. The general methodology of the Monte Carlo method is discussed and applied to the simulation of thermal radiation. …


The Use Of A High Level Cfd Code In Engineering Education, J.E.S. Venart, P. Lemieux, A.C.M. Sousa, D. Tatchell Jun 1991

The Use Of A High Level Cfd Code In Engineering Education, J.E.S. Venart, P. Lemieux, A.C.M. Sousa, D. Tatchell

Mechanical Engineering

An advanced multipurpose Computational Fluid Dynamics (CFD) code, FloSYS, developed for use in a CAD/CAE environment has been utilized in undergraduate and graduate courses in heat transfer. Problems are introduced at an introductory level in: -steady 2- and 3-dimensional conduction, -transient 1-, 2-, and 3-dimensional conduction, -free convective cavity flow with conjugate heat transfer, and -turbulent flows with heat transfer. More sophisticated problems, related to the use of porous media concepts for modelling heat exchangers, and compartment fire modelling are introduced at a more senior level. After one year's experimental use, the CFD code is being recommended for use in …


Acuta Enews June 1991, Vol. 20, No. 6 Jun 1991

Acuta Enews June 1991, Vol. 20, No. 6

ACUTA Newsletters

In This Issue

Panel to focus on fraud

Interactive video bandwidth

Aggregator requirements

Telex can still be useful

Penn State still pioneering

Positions availabe


Bearing Capacity Analysis Of Pavements, Tommy C. Hopkins Jun 1991

Bearing Capacity Analysis Of Pavements, Tommy C. Hopkins

Kentucky Transportation Center Research Report

A multilayered, mathematical model for analyzing the ultimate bearing capacity of soil subgrades and asphalt pavements is presented. Theoretical considerations and mathematical derivations of limit equilibrium equations, based on plasticity principles, for analyzing the ultimate bearing capacity of soil subgrades and partially completed asphalt pavements, and the extension of these equations to the analyses of asphalt pavements composed of multiple layers, are presented. The model is unique since shear strength parameters, Φ and c, (the angle of internal friction and cohesion, respectively) are used to describe each layer of material of the pavement structure and a factor of safety against …


Report Of The 12th F.V. Hunt Postdoctoral Fellow (1989-1990), E. Carr Everbach Jun 1991

Report Of The 12th F.V. Hunt Postdoctoral Fellow (1989-1990), E. Carr Everbach

Engineering Faculty Works

No abstract provided.


Network Model Investigation Of Gas Transport In Bidisperse Porous Adsorbents, John H. Petropoulos, John K. Petrou, Athanasios I. Liapis Jun 1991

Network Model Investigation Of Gas Transport In Bidisperse Porous Adsorbents, John H. Petropoulos, John K. Petrou, Athanasios I. Liapis

Chemical and Biochemical Engineering Faculty Research & Creative Works

A capillary network model consisting of a micropore network permeated by one of macropores of randomly varying size has been constructed. Although simplified (to keep computer space and time requirements low) in relation to a real bidisperse porous adsorbent or catalyst, it embodies the salient pore structural features likely to determine the gas-transport behavior of such porous solids. Suitable model calculations of Knudsen gas-phase and surface diffusion enabled us to (i) validate useful approximate methods for the more economical evaluation of network permeability and (ii) demonstrate certain important characteristic effects of nonrandom bidisperse pore structure on transport behavior and their …


Size Reduction Of Polymeric Particulates By Jet Milling, Cheng Hua May 1991

Size Reduction Of Polymeric Particulates By Jet Milling, Cheng Hua

Theses

A basic theory for the size reduction operation by jet milling has been developed.

Typical samples of feedstock have been analyzed using screen analysis to determine the initial distribution of polymeric particulate sizes prior to jet milling.

A statistical theory .was developed using probabilities to represent the likelihood that specific size reductions would occur. These probabilities include the effects of various equipment.

The theory was then used to predict the distribution of polymeric particulate sizes after jet milling. The agreement between the predictions and actual results was within 5 %.

Encouraged by the successful work of the simulation of the …


The Design And Testing Of A Personal Computer Controlled Scanning Acoustic Microscope For Orthopaedic Surgical Applications, Hubert Heinrich Berndt May 1991

The Design And Testing Of A Personal Computer Controlled Scanning Acoustic Microscope For Orthopaedic Surgical Applications, Hubert Heinrich Berndt

Theses

This thesis describes scanning acoustic microscopy and ultrasonic image processing to characterize and evaluate materials of known properties, as well as novel materials. This work describes the assembly and testing of a PC based device for nondestructive evaluation of bone materials for usage in orthopaedics research. It includes the identification of some hardware problems and their solution, and it also describes different image processing techniques that have been developed and applied in this work. In a growing number of disciplines it has been discovered that an acoustic microscope can provide new information, especially about the elastic properties of specimens and …


Workstation Allocation Schemes For Response Time Improvement In A Multiserver Pc Lan, Asit V. Merchant May 1991

Workstation Allocation Schemes For Response Time Improvement In A Multiserver Pc Lan, Asit V. Merchant

Theses

Microcomputer Local Area Networks have recently become quite popular. Higher demand in term of number of users who contribute a variable amount of load has led to Multiple File servers in a LAN. As a result of variable load, response time at workstations differ significantly depending not only on total load on the network but also on workstation distribution across servers. The goal of this study is to develop schemes to keep response time as low as possible and constant among workstations. This study is based on minimizing response time and containing it or keeping it constant by distributing workstations …


Performance Evaluation In Terms Of Congestion And Flow Control Of Interconnected Token Ring Local Area Networks, Muhammad Salim Raza May 1991

Performance Evaluation In Terms Of Congestion And Flow Control Of Interconnected Token Ring Local Area Networks, Muhammad Salim Raza

Theses

In an interconnected network, if user demands are allowed to exceed the system capacity, unpleasant congestion effects occur which rapidly neutralize the delay and efficiency advantages. Congestion can be eliminated by using an appropriate set of traffic monitoring and control procedures called flow control procedures. This thesis first investigates the major technical concepts underlying the token-ring technology; performance and flow control issues and then gives an approximate analytical solution in terms of mean end-toned delay in a system of token-ring local area network interconnected through bridges. The analytical solution is based on an approximation of the mean end-to-end delay in …


Off-Line Programming Using Igrip, Narahari K. Bhandary May 1991

Off-Line Programming Using Igrip, Narahari K. Bhandary

Theses

AT&T's FWS-200 (Flexible Work Station) has been modeled and simulated to implement Off-Line Programming (OLP). IGRIP (Interactive Graphics Robot Instruction Program) from Deneb Robotics, Inc. has been used to simulate the FWS operation.

A GSL(Graphics Simulation Language) program has been used to simulate the chip placements during PCB assembly. The program leads the user through the motions of chip placement, and after the simulation run downloads the motion sequence to the FWS. The animation sequences of the FWS have been downloaded to the FWS on the Factory Floor using a C program, which is utilized to communicate the data to …


A Process For Implementing Cim In A Small Manufacturing Facility, Tushar R. Desai May 1991

A Process For Implementing Cim In A Small Manufacturing Facility, Tushar R. Desai

Theses

This work is dedicated to small manufacturing enterprises seeking to explore Computer Integrated Manufacturing (CIM) technology, which is the recent trend in the manufacturing world. The main theme of this thesis is to improve productivity, product quality and reliability, and to reduce costs by integrating various discipline in small manufacturing environment, using computer technology.

To achieve this goal, a hypothetical small manufacturing company was chosen as a subject. The typical functional and organizational structures were analyzed and possible problem areas were highlighted. The problems relating to manufacturing process were studied in detail, and possible solutions were proposed to computerize the …


Acuta Enews May 1991, Vol. 20, No. 5 May 1991

Acuta Enews May 1991, Vol. 20, No. 5

ACUTA Newsletters

In This Issue

Golf outing set for St. Louis

Network ties islands together

Reorganization at Chicago

Recycling phone books

Party Line

Call for nominations


The Calendar - May 1991, Nova University May 1991

The Calendar - May 1991, Nova University

The Calendar

No abstract provided.


Field-Equation Approximations And The Dynamics Of High-Gain Lasers, Lee W. Casperson May 1991

Field-Equation Approximations And The Dynamics Of High-Gain Lasers, Lee W. Casperson

Electrical and Computer Engineering Faculty Publications and Presentations

Semiclassical models for laser-dynamics studies typically incorporate a derivative approximation that reduces the second-order wave equation for the electric field to a first-order equation. It is shown here that this approximation and further frequency approximations are not necessary and may lead to significant errors for some high-gain laser systems. A more exact analysis also reveals a partial decoupling of the electric and magnetic fields that occurs with fast transient phenomena. These ideas are illustrated in terms of well-known dynamical effects.


Metabolism Of Arachidonate-Containing Phospholipid Molecular Species In The Murine Macrophage-Like Cell Line, P388d1, Crystal R. Waites May 1991

Metabolism Of Arachidonate-Containing Phospholipid Molecular Species In The Murine Macrophage-Like Cell Line, P388d1, Crystal R. Waites

Electronic Theses and Dissertations

Glycerophospholipids of mammalian cells exist as chemically diverse structures with various fatty acids at the sn-1 and sn-2 positions. Arachidonic acid, a polyunsaturated fatty acid, which may be converted to biologically active eicosanoids such as prostaglandins, thromboxanes, and leukotrienes, is found predominantly in the sn-2 position of glycerophospholipids. The purpose of this study was to examine, at the level of the individual molecular species, the incorporation of arachidonate into phospholipids and its release from phospholipids during stimulation. In this way, the specificity of the enzymes controlling arachidonate metabolism could be examined in order to clarify the processes that control the …


Composition And Method For Radiation Synovectomy Of Arthritic Joints, D. E. Day, Gary J. Ehrhardt Apr 1991

Composition And Method For Radiation Synovectomy Of Arthritic Joints, D. E. Day, Gary J. Ehrhardt

Materials Science and Engineering Faculty Research & Creative Works

Radioactive microspheres for radiation synovectomy of arthritic joints in a mammal comprises a biodegradable glass material and a beta radiation emitting radioisotope chemically dissolved in and distributed substantially uniformly throughout the glass material. The biodegradable glass material may be lithium silicate, lithium aluminosilicate, lithium aluminoborate, lithium germa- nate, lithium aluminogermanate, potassium silicate, potassium aluminosilicate, potassium aluminoborate, potassium germanate or potassium aluminogermanate and the beta radiation emitting radioisotope may be samarium-153, holmium-166, erbium-169, dysprosium-165, rhenium-186, rhenium-188 or yttrium-90. Method for preparing such microspheres and for carrying out radiation synovectomy of arthritic joints utilizing such microspheres are also disclosed.


Radioactive Glass Microspheres, D. E. Day, Gary J. Ehrhardt Apr 1991

Radioactive Glass Microspheres, D. E. Day, Gary J. Ehrhardt

Materials Science and Engineering Faculty Research & Creative Works

A radioactive microsphere for radiation therapy of a mammal comprising a biologically compatible glass material containing a beta or gamma emitting radioisotope distributed substantially uniformly throughout the glass. Advantageously, the radioisotope is produced by irradiation of the microsphere.


Model Calculational Approach To The Conformation Of Adsorbed Polypeptide Fragments, Timothy J. Mckeon Apr 1991

Model Calculational Approach To The Conformation Of Adsorbed Polypeptide Fragments, Timothy J. Mckeon

Opportunities for Undergraduate Research Experience Program (OURE)

The focus of the paper is to examine possible conformational changes of peptides when placed in the presence of a poly-synthetic material. A major concern in the pharmaceutical industry is the loss of potency of polypeptide drug products during processing, packaging and storage. An example of this is polymer syringes being used in place of glass ones. The effect is that some protien-derived products experience structural changes due to contact with the polymer. This is otherwise known as surface denaturation. In order to understand the energetics of interfacial polypeptide systems, a calculational approach was used via the program Alchemy. The …


Acuta Enews April 1991, Vol. 20, No. 4 Apr 1991

Acuta Enews April 1991, Vol. 20, No. 4

ACUTA Newsletters

In This Issue

ACUTA Forum

Travel cards save money

Reorganization at Chicago

Regional Directors elected

Enchancing campus safety

Drew's Knowledge Initiative


Spring 1991, Wmpg 90.9 Fm Apr 1991

Spring 1991, Wmpg 90.9 Fm

WMPG Program Guides

WMPG program guide for Spring 1991

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


Santa Clara Magazine, Volume 33 Number 3, Spring 1991, Santa Clara University Apr 1991

Santa Clara Magazine, Volume 33 Number 3, Spring 1991, Santa Clara University

Santa Clara Magazine

12 - ABORTION : NO SIMPLE ANSWERS Jesuit theologian Ted Mackin examines pro-life and pro-choice positions and reports that neither side is addressing the issue with total honesty. By Theodore J. Mackin, S.J.

16 - STAY AT HOME MOMS Alumnae discuss why they decided to devote all their time and attention to their families. By Michelle Burget Fletcher '78, Brigid Modena Benham '81, and Anne Penoyer King '69

20 - SCU's WINE FAMILIES Northern California's vineyards are fertile ground for Santa Clara graduates. By Rosina Wilson

28 - WORKING THE SUICIDE HOTLINE Within these walls, no secret is too terrible …


The Calendar - April 1991, Nova University Apr 1991

The Calendar - April 1991, Nova University

The Calendar

No abstract provided.


An Erasable Optical Memory Based On Stimulated Electronic Transition Concept, James D. Satira Apr 1991

An Erasable Optical Memory Based On Stimulated Electronic Transition Concept, James D. Satira

Electrical & Computer Engineering Theses & Dissertations

Erasable optical memory systems with a high storage density and a large data transfer rate are required for many real time data acquisition systems such as those placed aboard NASA's space born platforms. A new concept for erasable optical memory involving stimulated electronic transitions (SET) will meet these requirements. The SET concept useful in erasable optical storage systems was demonstrated in MgS and SrS doped with Eu and Sm. The optical properties of these materials were studied. The reading and writing wavelengths for these samples were determined to be 950 and 514 nm respectively. The peaks of the emission spectra …


Two-Dimensional Heat Loss From A Building Slab Including Convective Effects In Saturated Soil, William W. Rust Iii Apr 1991

Two-Dimensional Heat Loss From A Building Slab Including Convective Effects In Saturated Soil, William W. Rust Iii

Mechanical & Aerospace Engineering Theses & Dissertations

The heat loss from a building slab was investigated. The continuity equation, Darcy's Law and the energy equation were formulated to include the temperature dependence of viscosity and density of water. The governing equations and appropriate boundary conditions were transformed into dimensionless variables. A finite difference numerical scheme was constructed based on the Gauss-Seidel method by lines and solved iteratively in alternating directions. A correlation between the geometrical characteristics of the domain, the convective surface heating parameters, and the total nondimensional slab heat loss in two dimensions was discovered. Furthermore, the correlation was extended to three-dimensional slabs and produced good …


General Report Session 9: Seismology: Predicting Strong Ground Motion For Design, Pierre-Yves Bard Mar 1991

General Report Session 9: Seismology: Predicting Strong Ground Motion For Design, Pierre-Yves Bard

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

The 14 papers of the session may be divided (somewhat artificially, of course) in three main subgroups: - a significant number (5) deal with the whole process of predicting strong ground motion for design, starting from geological / tectonic considerations and ending at a quantitative estimate of some ground motion parameters (peak acceleration, response spectrum,. .. ), either on a regional or national scale for zoning purposes (9.17, 9.24), or at a specific site for the design of some specific structures (papers 9.10, 9.13), or finally from a methodological point of view ( 9.13, 9.24, 9.26). - the 7 papers …


Session 10: Discussions And Replies, Multiple Authors Mar 1991

Session 10: Discussions And Replies, Multiple Authors

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

No abstract provided.


Generalized Rayleigh Waves In Layered Solid-Fluid Media, Hua Hui Tan Mar 1991

Generalized Rayleigh Waves In Layered Solid-Fluid Media, Hua Hui Tan

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

A finite-element method for the propagation of Rayleigh-type waves in layered solid-fluid media is presented. The method uses displacement as the only parameter to describe the solid and the fluid motions. A penalty function method and a selective integration technique are employed to change the elastic coefficient matrix of fluid from singular to nonsingular. Results obtained from the proposed method agree well with those obtained from available analytical solutions. The method can be used to study the propagation of Rayleigh-type waves in a two-dimensional, irregular solid-fluid system.