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Ultrasonic Radiative Transfer In Polycrystalline Media: Effects Of A Fluid–Solid Interface, Joseph A. Turner, Richard L. Weaver

Department of Engineering Mechanics: Faculty Publications

In previous derivations of the ultrasonic radiative transfer equation (URTE) for the modeling of multiply scattered diffuse ultrasound in polycrystalline media, the boundary conditions appropriate to experiments performed in a water bath were not used. In the present work, this fluid–solid boundary condition is discussed as it applies to the URTE. An interpolation scheme is developed that is consistent with the discrete ordinates method used for the solution of the URTE. Steady-state and time-dependent results are presented for the solution of the URTE with a fluid–solid boundary condition. The steady-state results show that diffusive behavior is exhibited nearer the specimen …

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 11, Number 9, November 1995, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

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

Image Restoration Of Dispersion-Degraded Images From A Liquid-Crystal Beam Steerer, Ronald J. Broessel, Vince Dominic, Russell C. Hardie

Electrical and Computer Engineering Faculty Publications

Liquid-crystal arrays represents one of the first practical technologies capable of steering light by electronic control only. We use such a device to steer the field of view of a broadband imaging sensor. Unfortunately, dispersion degrades the image quality by smearing out details in the image and by introducing multiple diffraction orders (echoes) at the detector plane. We present a method to compensate for these unwanted effects and thus restore the broadband images obtained with the beam steerer. We use the beam-propagation method to find the wavelength-dependent impulse response, from which we determine the appropriate Wiener filter. When training data …

Photovoltaic Applications For Disaster Relief, Florida Solar Energy Center, William Young

FSEC Energy Research Center®

Hurricanes, floods, tornadoes, and earthquakes are natural disasters that can happen at any time destroying homes, businesses, and natural surroundings. One such disaster, Hurricane Andrew, devastated South Florida leaving several hundred-thousand people homeless. Many people were without electrical service, functioning water and sewage systems, communications, and medical services for days, even weeks in the aftermath of the storm. Emergency management teams, the military and countless public and private organizations staged a massive relief effort. Dependency on electrical utility power became a pronounced problem as emergency services were rendered to survivors and the rebuilding process started.

Many of the energy needs …

Fault Tolerant Training For Optimal Interpolative Nets, Daniel J. Simon, Hossny El-Sherief

Electrical and Computer Engineering Faculty Publications

The optimal interpolative (OI) classification network is extended to include fault tolerance and make the network more robust to the loss of a neuron. The OI net has the characteristic that the training data are fit with no more neurons than necessary. Fault tolerance further reduces the number of neurons generated during the learning procedure while maintaining the generalization capabilities of the network. The learning algorithm for the fault-tolerant OI net is presented in a recursive formal, allowing for relatively short training times. A simulated fault-tolerant OI net is tested on a navigation satellite selection problem

Customizable Operating Systems, Jonathan Walpole, Crispin Cowan, Andrew P. Black, Jon Inouye, Calton Pu, Shanwei Cen

Computer Science Faculty Publications and Presentations

A customizable operating system is one that can adapt to improve its functionality or performance. The need for customizable and application-specific operating systems has been recognized for many years, but they have yet to appear in the commercial market. This paper explores the notion of operating system customizability and examines the limits of existing approaches. The paper begins by surveying system structuring approaches for the safe and efficient execution of customizable operating systems. Then it discusses the burden that existing approaches impose on application software, and explores techniques for reducing this burden. Finally, support for customizability in the Synthetix project …

Quality Of Service Specification For Multimedia Presentations, Richard Staehli, Jonathan Walpole, David Maier

Computer Science Faculty Publications and Presentations

The bandwidth limitations of multimedia systems force tradeoffs between presentation data fidelity and real-time performance. For example, digital video is commonly encoded with lossy compression to reduce bandwidth and frames may be skipped during playback to maintain synchronization. These tradeoffs depend on device performance and physical data representations that are hidden by a database system. If a multimedia database is to support digital video and other continuous media data types, we argue that the database should provide a Quality of Service (QOS) interface to allow application control of presentation timing and information loss tradeoffs.

This paper proposes a data model …

Device And Physical Data Independence For Multimedia Presentations, Richard Staehli, Jonathan Walpole, David Maier

Computer Science Faculty Publications and Presentations

Multimedia computing promises access to any type of visual or aural medium on the desktop. But in this networked future, will every type of media be accessible from every terminal device? Current multimedia standards do not allow content that is authored for high-bandwidth workstations to scale down for low-bandwidth applications. The problem is that application requests are commonly interpreted as requests for the highest possible quality and resource overloads are handled by ad hoc methods. We can begin to solve this problem by specifying Quality of Service (QOS) requirements based on functionality rather than on content encoding and device capabilities.

Device And Physical Data Independence For Multimedia Presentations, Richard Staehli, Jonathan Walpole, David Maier

Computer Science Faculty Publications and Presentations

Multimedia computing promises access to any type of visual or aural medium on the desktop. But in this networked future, will every type of media be accessible from every terminal device? Current multimedia standards do not allow content that is authored for high-bandwidth workstations to scale down for low-bandwidth applications. The problem is that application requests are commonly interpreted as requests for the highest possible quality and resource overloads are handled by ad hoc methods. We can begin to solve this problem by specifying Quality of Service (QOS) requirements based on functionality rather than on content encoding and device capabilities.

Computer-Aided Process Design For Waste Minimization, Konstadinos Abeliotis

Dissertations

Problems related to process design with environmental considerations have been studied in this dissertation. A new heuristic design methodology has been formulated with the objective of minimizing the adverse environmental impact of chemical processes.

This hierarchical methodology starts with the definition and analysis of a process flowsheet followed by quantification of the process environmental loads. The quantification of environmental loads is an essential aspect of this methodology, because it serves as the comparative measure for environmental performance.

If the calculated environmental loads do not satisfy the environmental constraints (e.g., regulatory limits), waste minimization is investigated in the following order:

• Pollution …

A Theoretical Analysis Of Volatile Contaminant Removal By The Pneumatic Fracturing Process, Yuan Ding

Dissertations

A mathematical model that simulates the process of contaminant removal from a pneumatically induced fracture within a porous medium is presented. It includes: (1) model development; (2) parameter evaluation; (3) statistical sensitivity analysis; and (4) model validation.

Based on the dual porosity approach, a mathematical model for a fractured porous formation is developed for both two dimensional and axial symmetrical cases. This model constitutes a pair of coupled partial differential equations for the porous medium and discrete fracture, respectively. The initial and boundary conditions have been determined based on field considerations of a soil vapor extraction system. By means of …

Synthesis Of Boron Nitride/Vycor Composite Membrane Structures By An Optimized Lpcvd Process, Chenna Ravindranath

Theses

Since the advent of the idea of ultrafiltration, microporous membranes have come through a long way in establishing a niche as an efficient technology for gas separation applications. More and more research is aimed at reducing pore size towards nanolevels, when separation factor is the criterion rather than the permeability. This work is focused at synthesizing and characterizing microporous inorganic membranes for gas separations by molecular sieving. BN was deposited on mesoporous vycor tubes using triethylamine borane complex (TEAB) and ammonia as precursors. Effect of temperature and deposition geometry on permeability of various gases has been studied. Very high selectivities …

Chute Flow Experiments, Yahong Zhang

Theses

The objective of this thesis is to study the behavior of granular materials flowing down an inclined chute using three diagnostic techniques under different chute inclination angles and chute floor conditions. The three methods are: (1) tracking the motion of single particle within the mass in a noninvasive manner using a transmitting sphere and antenna receiving system, (2) scale mass flow rate measurement, and (3) high speed camera system to obtain flow velocity measurements.

For these purposes, an experimental setup has been completed and a set experiments has been performed.

Analysis Of Cim Performance Using Different Lan Structures A Simulation Approach, Kirk Rawle

Theses

This research illustrates a systematic procedure for modeling and performance analysis of the integration effect of communication network to the physical system. The concept is to model different layouts of Computer Integration Manufacturing (CIM) using different Local Area Network(LAN) structures. The steps to accomplish this concepts are, a) To determine the performance measures for physical layouts and the communication network, in order to obtain a performance analysis. b) Modeling the physical layout using Promodel simulation package. c) Extracting results from the outcome of the simulation of the physical layout and using this as input to the communication network simulation. d) …

Reverse Osmosis As A Pretreatment Of Ion Exchange Equipment At Pse & G'S Hudson Generation Station, Steven Leon

Theses

Public Service Electric and Gas Company's Hudson Generating Station has historically had problems providing sufficient high quality water for its two once through, supercritical design boilers. The station requires over 60 million gallons annually to compensate for system losses.

The stations' ion exchange demineralizers proved to be costly to operate and overall inefficient in performance. Drawbacks include: short service cycles, periodic contamination of storage tanks due to premature breakthrough, prohibitively high chemical regenerant costs, excessive labor requirements, frequent resin replacement, and overall unreliable plant operations.

A reverse osmosis unit was installed as a pretreatment to the demineralizers to offset these …

Acuta Enews October 1995, Vol. 24, No. 10

ACUTA Newsletters

In This Issue

From the President

Disaster Recovery: Part ll

PBX Call Processing Basics

Cal State lnstalls Intelligent Payphones

From ACUTA Headquarters

Civilizing The Civil Engineer: How A History Course Can Serve As A Curriculum Capstone, John Alfred Heitmann

History Faculty Publications

Beginning in 1989 and then every other year thereafter, a unique course dealing specifically with the history of civil engineering has been taught to all civil engineering majors at the University of Dayton. What has evolved over time -- in response to student feedback, ongoing reform in the curriculum, and a maturing of faculty expertise -- is a course in the history of civilization that has as its major focus the discipline of civil engineering.

In reality, what happens in the classroom is a far broader learning experience than either the disciplines of history or civil engineering could provide standing …

Bulletin - October, 1995, Civil Aviation Medical Association

Browse all Civil Aviation Medical Association Newsletters

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

A Characterization Of Alternative Tooling Materials Using Impact Abrasion Testing, Michael C. Formanek

Graduate Research Papers

The purpose of this study was to evaluate the wear resistance of tooling materials using impact abrasion testing. Materials tested are being used or are being considered for use in pattern and corebox construction. This study used 14 materials for evaluation. The materials were chosen on the basis of recommendations made by manufacturers and patterns shops. This study used the same procedure established in a study done in 1992 by Vondra to evaluate materials against a standard sample.

Of the materials tested three were included in the ceramics group. These materials demonstrated average wear resistance. The percent weight loss ranged …

An Investigation Into The Use Of Expanded Polystyrene Patterns With The Loose-Sand, Vacuum Assisted Counter Gravitational Casting Process, John B. Vandersall

Graduate Research Papers

"Considered for years as a metal casting renegade, Expendable Pattern Casting (EPC) is believed by some to be tomorrows long-term casting future. Others, however, see it as an unproven headache-ridden process that makes the simple art of metal casting unnecessarily complex." (Lessiter, 1994, p. 36). The complexity of this process has been largely due to the lack of knowledge surrounding the interaction of the metal front and the dissipating polystyrene pattern.

Since the discovery of EPS as a pattern material, numerous applied research projects have been performed to gain a better understanding of the thermal breakdown characteristics of the material. …

Text Independent Speaker Verification Using Binary-Pair Partitioned Neural Networks, Claude A. Norton Iii

Electrical & Computer Engineering Theses & Dissertations

A method is presented for the application of binary-pair partitioned neural networks to the task of speaker verification. This technique is based on a previously developed neural network classifier for speaker identification.

The main focus of this research was the development and testing of the algorithms necessary to extend the binary-pair partitioning approach from speaker identification to speaker verification. The method is based on the development of a user profile which is obtained from discriminative data provided by the binary-pair partitioned neural networks.

Experimental results are provided which demonstrate the viability of this approach, using the TIMIT speech corpus for …

Process For Converting Serial Image To The Sterolithography Apparatus (Sla) Slice File With Automatic Base And Support Generation, Charles F. Knapp, P. L. Charles Fischer, Samuel V. Duplessis

Biomedical Engineering Faculty Patents

Method and apparatus for converting a series of serial section images of an object into a three-dimensional model. The method includes acquiring and storing the series of serial section images, converting, zooming, and interpolating serial section images. The method further includes discriminating the series of serial section images to form a binary image, which is then compressed, and filtered. Further, support data for floating or cantilevered portions of the object and base data are generated, the filtered binary image is translated to produce a plurality of vectors representing pixels of the object, and a three-dimensional model of the object is …

Teaching Upper Level Computer Science Courses Via Virtual Classroom And Video : Course Reports By Faculty, Computerized Conferencing & Communications Center, Starr Roxanne Hiltz, Julian M. Scher, Michael Bieber, Murray Turoff

Computerized Conferencing and Communications Center Reports

New Jersey Institute of Technology is the grateful recipient of a generous grant from the Alfred P. Sloan Foundation which has enabled it to explore the use of asynchronous learning networks to create and deliver an entire undergraduate degree program in computer and information science. Each of these courses uses some amount of lecture-type material delivered via videotape. These materials are usually available to students in three different ways: by viewing broadcasts on a New Jersey cable station, by renting the set of videotapes, or by viewing in a special room in the library. Videotapes for distance learning are not …

Teaching Lower Level Computer Science Courses Via Virtual Classroom And Video : Course Reports By Faculty, Computerized Conferencing & Communications Center, Starr Roxanne Hiltz, Fadi Deek, Maura Deek, James Geller, Ajaz R. Rana

Computerized Conferencing and Communications Center Reports

New Jersey Institute of Technology is the grateful recipient of a generous grant from the Alfred P. Sloan Foundation which has enabled it to explore the use of asynchronous learning networks to create and deliver an entire undergraduate degree program in computer and information science. Each of these courses uses some amount of lecture-type material delivered via videotape. These materials are usually available to students in three different ways: by viewing broadcasts on a New Jersey cable station, by renting the set of videotapes, or by viewing in a special room in the library. Videotapes for distance learning are not …

The Process Of Technology Transfer: A Case Study Of The National Aero-Space Plane Program, Brett T. Smith

Theses and Dissertations

Due to reduced funding levels and increased pressure towards cooperation with industry, government research and development (R&D) organizations are becoming increasingly involved in the transfer of technology to the commercial sector. However, the process of technology transfer is complex, and transfer activities are being applied inconsistently across the Department of Defense. This research explores the approaches, processes and mechanisms to accomplish technology transfer. A comprehensive literature review documents many of the transfer concepts that have been proposed or are currently in use. A detailed case study then examines the technology transfer efforts of an advanced government research organization: the National …

Broadband Dynamic, Holographically Self-Recorded, And Static Hexagonal Scattering Patterns In Photorefractive Knbo3:Fe, Nickolai Kukhtarev, Tatiana V. Kukhtareva, John Caulfield, Partha P. Banerjee, Hsueh-Ling Yu, Lambertus Hesselink

Electrical and Computer Engineering Faculty Publications

We have observed and explained three types of hexagon pattern formation in photo refractive crystal KNb03:Fe. These are:

• Dynamic (laser induced)
• Semipermanent (holographically stored)
• Permanent (induced by a static domain grid) over a wide wavelength range

Transient Wave Mixing And Recording Kinetics In Photorefractive Barium Titanate: A Nonlinear Coupled Mode Approach, Partha P. Banerjee, John M. Jarem

Electrical and Computer Engineering Faculty Publications

By using rigorous coupled-wave diffraction theory along with a time-dependent nonlinear formulation, we analyze two- and multiplewave coupling and the grating kinetics in BaTi03 with different boundary interfaces. Efffects of electrostatic and optical anisotropy have been included in the analysis. Significant mode conversion to higher orders is observed only when the boundary interfaces are highly mismatched.

Comparison Of Time-Domain Reflectometry Performance Factors For Several Dielectric Geometries: Theory And Experiments, S. V. Maheshwarla, R. Venkatasubramanian, Robert F. Boehm

Electrical & Computer Engineering Faculty Research

We propose three nontraditional dielectric geometries and present an experimental and theoretical analysis and comparison of time domain reflectometry (TDR) performances for them. The traditional geometry (the probes inserted in material of essentially infinite extent) is compared to three nontraditional geometries where the probes are affixed outside of a core sample, inside of a bore, or flat on the surface of a semi-infinite solid. Our derivation relates the velocity of electromagnetic wave propagation to the complex permittivities and permeabilities of the media and the geometry for the three nontraditional configurations. Experimental results for air, styrofoam, dry sand, wet sand of …

Guest Editorial: Special Section On Photorefractive Nonlinear Optics, Partha P. Banerjee

Electrical and Computer Engineering Faculty Publications

Hand in hand with experimental work in photorefractives, there is a lot of activity in modeling photorefractive materials and experimental observations in the open literature. This special section contains a paper by Banerjee and Jarem, who use a rigorous coupled wave theory to analyze two- and multiple-wave mixing photorefractive barium titanate, modeled through the Kukhtarev equations.

Optimal Pumping Strategies To Maximize Dissolved Tce Extraction At Central Base Area, Norton Afb, California, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

Norton Air Force Base (NAFB) is located in the San Bernardino Valley, part of the California Peninsular Range geomorphic province (Figure 1). The elevation at NAFB is about 1,100 feet above mean sea level (msl). The ground slopes gradually to the southwest.