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An Analytical Approach To Toxic Substance Replacement In Support Of Pollution Prevention, Ithan B. Zimmer

Theses

In support of pollution prevention and in accordance with Executive Order 12356 concerning pollution prevention, all federal agencies must comply with the Toxic Release Inventory (TRI) chemical release reduction and pollution prevention planning. The inventory lists hundreds of chemicals and choosing those to replace and finding actual replacement chemicals or procedures is not always clear. This study focuses on an analytical approach to this problem by understanding the application of two substances. The representative chemicals are two volatile organic compounds (VOC), ethyl ether and ethanol, used as solvents in ammunition manufacturing.

Thirteen military specifications provide the cases involving ether. Ethanol's …

Electrodeposition Of Amorphous Fe-Cr Alloy Coating, Danhong Cheng, Weiyi Xu, Yiqin Qin, Liqun Hua, Zhongyan Zhang

Journal of Electrochemistry

The amorphous Fe-Cr alloy coatings were obtained by controlling the composition of bath operation conditions. It was found that the pH value, the current density and the content of chromium in Fe-Cr alloy coatings effect the amorphous structure of the coatings. The result of anodic polarization shows that the corrosion resistance of the amorphous coatings in acidic media is higher than the corrosion resistance of the crystal ones.

1997 - The Second Annual Symposium Of Student Scholars

Symposium of Student Scholars Program Books

The full program book from the Second Annual Symposium of Student Scholars, held on May 23rd, 1997. Includes abstracts from the presentations and posters.

Cr9000 Measurement And Control System Pcmcia-Ata Software Device Interface, Ryan Jon Soulier

Undergraduate Honors Capstone Projects

Many industries have a need for high speed data collection of a large amount of data. For example, the auto industry extensively tests vehicles for resistance to stress, temperature, and moisture. Campbell Scientific, Inc. (CSI) has built the CR9000 measurement and control system that fills this need by being able to measure up to 252 separate sensors at a sustained rate of up to ten thousand samples per second.

The CR9000 system lacks efficiency because it has only a small, fixed amount of memory and is capable of recording data only for a short period. Older devices designed by CSI …

Predictable File Access Latency For Multimedia, Dan Revel, Crispin Cowan, Dylan Mcnamee, Calton Pu, Jonathan Walpole

Computer Science Faculty Publications and Presentations

Multimedia applications are sensitive to I/O latency and jitter when accessing data in secondary storage. Transparent adaptive prefetching (TAP) uses software feedback to provide multimedia applications with file system quality of service (QoS) guarantees. We are investigating how QoS requirements can be communicated and how they can be met by adaptive resource management. A preliminary test of adaptive prefetching is presented.

Uptake And Metabolism Of Atrazine By Poplar Trees, Joel Gerard Burken, Jerald L. Schnoor

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Hybrid Poplar Trees Can Uptake, Hydrolyze, and Dealkylate Atrazine to Less Toxic Metabolites. in Whole Plant Studies, the Parent Compound Atrazine and 14C Ring-Labeled Metabolites Were Extracted from Poplar Tissues and Analyzed Via High-Pressure Liquid Chromatography (HPLC) with UV and Radiochromatographic Detectors in Series. the Concurrent Separation and Identification of These Metabolites Has Not Been Previously Reported in Higher Plants for Phytoremediation Applications. Unidentified Metabolites Were Also Detected. Metabolism of Atrazine Occurred in Poplar Roots, Stems, and Leaves and Became More Complete with Increased Residence Time in Tissues. in Poplar Cuttings Exposed to Atrazine for 50 Days, the Parent Compound …

The Synthesis, Characterization, And Cell Seeding Of A Collagen/Hydroxyapatite Porous Scaffold For Treatment Of Osseous Defects, Kim Rachel Patterson

All Theses

The need for finding a bone graft substitute stems from the fact that approximately 200,000 bone grafting procedures are performed annually in the U.S. alone. Although biological grafting options (i.e. autografts & allografts) exist, they do suffer from inherent problems. These include limited resources, costly processing, and potential for pathogen transfer. Thus, investigators have sought synthetic alternatives.

The objective of this research was to utilize hydroxyapatite (HA) and collagen, both analogues to the major constituents of bone, to fabricate an optimal synthetic osteoconductive/osteoinductive bone scaffold. Current attempts by other investigators to combine the two materials have been met with some …

Secondary Dark Rings Of Internal Conical Refraction, Karl F. Warnick, David V. Arnold

Faculty Publications

This paper treats the phenomenon of internal conical refraction, in which a narrow beam propagating along an optical axis of a biaxial anisotropic medium spreads into a hollow cone. An expression is obtained for the intensity distribution produced by conical refraction that predicts additional fringes concentric to the well known Poggendorf dark ring for certain propagation distances and beam widths.

Santa Clara Magazine, Volume 39 Number 1, Spring 1997, Santa Clara University

Santa Clara Magazine

6 - BLUE SKY INVASION Searching for the American Dream, aerospace workers transform the Santa Clara Valley. By David Beers '79, Illustrations by Dug Waggoner

15 - SEEING IS BELIEVING Professor Sally Wood develops software to help students visualize basic engineering concepts. By Laura Trujillo '92

18 - CONFRONTING THE SCARS OF CENTURIES A legal challenge to California's Proposition 209 is the latest round in a long- running debate over affirmative action. By Margaret M. Russell

26 - SHADOWY ALLIANCE A recent expose alleging CIA links to the crack cocaine epidemic in California's inner cities raises questions about responsibility and …

Generalized Beam Matrices. Iv. Optical System Design, Anthony A. Tovar, Lee W. Casperson

Electrical and Computer Engineering Faculty Publications and Presentations

Systematic procedures are presented for determining the optical components needed to produce an arbitrary transformation of a Gaussian light beams's spot size, radius of curvature, displacement, and direction of propagation. As an example, an optical system is considered that spatially separates the two coincident Gaussian beams produced by a high-diffraction-loss resonator that uses a Gaussian variable-reflectivity output coupler. In addition, an ABCDGH reverse matrix theorem and an ABCDGH Sylvester theorem are also derived. These matrix theorems may be used to satisfy special constraints inherent in the design of multipass and periodic optical systems.

Predicting Timing Behavior In Architectural Design Exploration Of Real-Time Embedded Systems, Rajeshkumar Sambandam

Masters Theses

This thesis aims at developing efficient analytical techniques to perform trade-off studies in the architectural design exploration phase of real-time embedded systems. Real-time embedded systems (RTES) have stringent timing requirements. In the process of designing such a system, a key issue is to determine if a system is able to meet all the timing requirements imposed on it, though it may prove attractive in terms of cost and performance. Traditional methods of using event-driven simulation for modern RTES are very time consuming and are not guaranteed to prove feasibility. Specifically, we identify a flexibility metric to compare various options in …

A Sociotechnical Systems Analysis Of The Approval Process For A Complex Public Works Proposal, James C. Pyne

Engineering Management & Systems Engineering Theses & Dissertations

This research applied sociotechnical systems theory to explore the process used by two elected bodies to decide upon adoption of a complex technical engineering proposal. The research used a modified sociotechnical systems conceptual framework that was developed by Pava (1983) for application to non-traditional work settings. Pava applied the conceptual framework to what he termed non-routine office work which is characterized by non-linear conversion flow, multiple, concurrent conversion processes and vocational separatism (Pava, 1983).

The research was designed as a multiple case study of two town councils each undertaking a decision process to approve or reject a public works proposal …

High Resolution Wavelength Modulation Spectroscopy For Precise Gaseous Characterization, Audra Michiele Bullock

Electrical & Computer Engineering Theses & Dissertations

Wavelength modulation spectroscopy is a highly sensitive, non-intrusive technique for probing gaseous species. Parameters such as velocity, density, and temperature can be measured and monitored with a high degree of precision. In addition, with the use of this technique multiple molecular species may be identified with a single laser probe. This measurement technique utilizes the well-known principles of modulation absorption spectroscopy in a novel way.

The research focuses on harmonic detection and the advantages gained by performing detection at higher harmonics, those greater than the commonly used second harmonic. We show that there is an increase in the sensitivity to …

Rate-Equation Approximations In High-Gain Lasers, Lee W. Casperson

Electrical and Computer Engineering Faculty Publications and Presentations

The rate-equation approximation is one of the most fundamental and universally employed simplifications in laser analyses. The accuracy and regions of applicability of this approximation are explored in comparisons with more rigorous semiclassical models. Higher-order rate-equation approximations are also developed, and these improved models can yield much better accuracy than conventional rate equations with little added complexity. The modified adiabatic elimination methods reported here would also be useful in reducing the mathematical models governing other physical systems.

Bs News

Building Services Engineering

No abstract provided.

Acuta Enews March 1997, Vol. 26, No. 3

ACUTA Newsletters

In This Issue

Student Paper Competition Nears Deadline

U.S. Court of Appeals stays FCC Detariffing Order

Board Nominations Due April 12

Welcome New Members

Board Report

Same as Sales, But No Commission

Spotlight

DC at a Glance

Publications Committee

ACUTA Membership Renewal

Ultrasonic Method For Evaluation Of Annular Seals For Wells And Instrument Holes, Nazli Yesiller, Tuncer B. Edil, Craig H. Benson

Civil and Environmental Engineering

An ultrasonic testing method employing the pulse-echo inspection technique was developed to assess the integrity of annular seals surrounding casings (i.e., instrument tubes or well casings). This nondestructive testing method permits testing a seal from inside a casing without disturbing the casing, seal, or formation. Seals constructed with cement-based and bentonite-based sealants surrounding various types and sizes of casings can be evaluated using the method. An evaluation is conducted by sending and receiving ultrasonic waves using a single piezoelectric transducer and commercially available hardware (a pulser receiver and a waveform analyzer). A probe was designed and constructed for downhole testing. …

Performance Of Mhpm In Rician And Rayleigh Fading Mobile Channels, Fuqin Xiong, S Bgatnyket

Electrical and Computer Engineering Faculty Publications

This paper evaluates the error probability of the rectangular frequency pulse multi-h modulation (MHPM) scheme in slowly-fading, frequency-nonselective or frequency-selective Rician and Rayleigh channels. The evaluation is performed with a method combining analysis and computer simulation. Performance degradations are evaluated for various direct-to-reflected signal ratio, Doppler shifts, and relative time delays in Rician fading channels. Compared with minimum shift keying (MSK), MHPM schemes appear to have retained their coding gains

A Cercla-Based Decision Support System For Environmental Remediation Strategy Selection, Brian J. Grelk

Theses and Dissertations

The Idaho National Environmental Engineering Laboratory (INEEL), operating in conjunction with the Department of Energy (DOE), faces with the complex decision of selecting an environmental remediation strategy for the Subsurface Disposal Area (SDA) of the Radioactive Waste Management Complex (RWMC). This research uses value-focused thinking and multiattribute preference theory techniques to produce a decision analysis model to aid the decisionmakers as they select a remediation strategy. A deterministic analysis using expert opinion and the best available engineering data demonstrates the model's capabilities. The model ranks 27 specific remediation strategies based on how well they meet CERCLA's five balancing criteria: implementability, …

Electromagnetic Scattering From A Cavity In A Ground Plane: Theory And Experiment, William D. Wood Jr.

Theses and Dissertations

The electromagnetic scattering from an arbitrarily shaped open cavity embedded in a perfectly conducting, infinite ground plane is examined. The cavity is filled with a linear, isotropic, homogeneous material. The fields in the cavity interior and above the ground plane are expressed in terms of the tangential fields on the cavity surface and aperture. A coupled set of three integral equations is developed governing the tangential fields on the aperture and cavity surface. The support of the unknown tangential fields is finite. A moment-method based algorithm to approximate the solution to the integral equations for axisymmetric geometries is developed. The …

Advances In Time-Domain Electromagnetic Simulation Capabilities Through The Use Of Overset Grids And Massively Parallel Computing, Douglas C. Blake

Theses and Dissertations

A new methodology is presented for conducting numerical simulations of electromagnetic scattering and wave propagation phenomena. Technologies from several scientific disciplines, including computational fluid dynamics, computational electromagnetics, and parallel computing, are uniquely combined to form a simulation capability that is both versatile and practical. In the process of creating this capability, work is accomplished to conduct the first study designed to quantify the effects of domain decomposition on the performance of a class of explicit hyperbolic partial differential equations solvers; to develop a new method of partitioning computational domains comprised of overset grids; and to provide the first detailed assessment …

Estimation Of Pore Diameter For Intraparticle Fluid Flow In Hidisperse Porous Chromatographic Particles, G. A. Heeter, Athanasios I. Liapis

Chemical and Biochemical Engineering Faculty Research & Creative Works

A quantitative method is developed and presented for estimating the mean pore diameter, d(pore), that could allow intraparticle fluid flow in the macroporous region of adsorbent particles with a bidisperse porous structure packed in a column. The method is used to estimate the value of d(pore) that is required to obtain specified values of the fraction, F, of the column superficial fluid velocity that is flowing through the macroporous region of the adsorbent particles and the value of d(pore) that is required to obtain specified values of the intraparticle Peclet number, Pe(intra).

Numerical Simulation Of Contaminated Sediment Transport In The Upper Columbia Slough System, Binghong Wu

Dissertations and Theses

An integrated modeling system has been developed to simulate sediment and contaminated sediment transport in the Upper Columbia Slough System during the Flood of 1996. The modeling system consists of a hydrodynamic model, a sediment transport model, and a contaminant transport model. The hydrodynamic model predicts the Slough flow dynamics and sediment transporting power; the sediment transport model predicts flow-induced sediment transport; and the contaminant transport model predicts the migration of contaminated sediments in the Slough system.

The Upper Columbia Slough modeling system is characterized by its recognition of the complex interplay of Slough hydrology, hydrodynamics, sediment transport, contaminant transport. …

Residual Strength Of Equine Bone Is Not Reduced By Intense Fatigue Loading: Implications For Stress Fracture, R. B. Martin, V. A. Gibson, S. M. Stover, J. C. Gibeling, L. V. Griffin

Biomedical Engineering

Fatigue or stress fractures are an important clinical problem in humans as well as racehorses. An important question in this context is, when a bone experiences. fa!igue damage ~uring e~treme use, how much is it weakened compared to its original state? Since there are very ltmtted data on thts quesuon and stress fractures are common in racehorses, we sought to determine the effect of fatigue loading on the monotonic l:trength of equine cortical bone. Beams were machined from the dorsal, medial and lateral cortices of the third metacarpal bones of six thoroughbred racehorses. Beams from left and right bones were …

Teaching Electromagnetic Field Theory Using Differential Forms, Karl F. Warnick, Richard H. Selfridge, David V. Arnold

Faculty Publications

The calculus of differential forms has significant advantages over traditional methods as a tool for teaching electromagnetic (EM) field theory. First, films clarify the relationship between field intensity and flux density, by providing distinct mathematical and graphical representations for the two types of fields. Second, Ampere's and Faraday's laws obtain graphical representations that are as intuitive as the representation of Gauss's law. Third, the vector Stokes theorem and the divergence theorem become special cases of a single relationship that is easier for the student to remember, apply, and visualize than their vector formulations. Fourth, computational simplifications result from the use …

Evaluation Of Environmental Characteristics Of Wtp Residuals For Disposal In Monofills, Ping Tian

Dissertations

Disposal of water treatment plant (WTP) have raised great concerns due to the stringent water quality standards and environmental regulations, and limited availability of land for ultimate disposal. The ultimate disposal of water treatment plant residuals by using monofill may be one of the most economical, and feasible options. Design and operation of such a monofill will be simple because of the uniformity of the characteristics of WTP residuals.

The objectives of this project were to determine the environmental characteristics of WTP residuals and to apply these characteristics for the design of monofills and development of the metal leaching model …

Shaped Charges Having A Porous Tungsten Liner-An Experimental And Theoretical Study Of Metal Compression, Jet Formation And Penetration Mechanics, Brian Edward Fuchs

Dissertations

The use of porous tungsten as a liner for shaped charges to improve their penetration was proposed by Ki-Hwan Oh in his invention disclosure "Shock Extrusion of Ingots from Powders or Solids", at the New Mexico Institute of Mining and Technology, Socorro NM on June 7, 1988. The intention was to increase the ductility of the normally brittle metal by heating the liner to a high temperature by shock compaction during its acceleration just before jet formation.

The feasibility of increasing the ductility of tungsten in this way is the subject of the present study. The theory and prior experimental …

Performance Evaluation Of Cebus Power Line Communication In The Presence Of X-10 Module Signaling, Nashwa F. Kamel

Theses

A power line of CEBus has great potential towards inexpensive home automation. Both PLBus and X-10 uses [sic] burst of 120KHz signals to transmit bits of information on the power line. However, these two systems are completely incompatible and can conflict with each other. This thesis presents the first performance evaluation of Power Line CEBus communication in the presence of X-10 module signaling. The evaluation included simulation experiments measuring packet delays, message delays, message throughput, channel throughput and the percentage of messages received in error verses [sic] different loads. Network performance has been confirmed to function well in terms of …

Tcp/Ip Traffic Over Atm Network With Abr Flow And Congestion Control, Liping An

Theses

Most traffics over the existing ATM network are generated by applications running over TCP/IP protocol stack. In the near future, the success of ATM technology will depend largely on how well it supports the huge legacy of existing TCP/IP applications.

In this thesis, we study and compare the performance of TCP/IP traffic running on different rate based ABR flow control algorithms such as EFCI, ERICA and FMMRA by extensive simulations. Infinite source-end traffic behavior is chosen to represent, FTP application running on TCP/IP. Background VBR traffic with different ON-OFF frequency is introduced to produce transient network states as well as …

Microporous Silicon Dioxide/Vycor Membranes For Gas Separation, Justin R. Barone

Theses

This study focused on producing membranes for molecular sieving of gases by reducing the pore size of an already existing membrane structure. To do this, SiO₂ was deposited inside the pores of a Vycor tube with initial pore diameter of 4 nm. The film deposition took place by a low pressure chemical vapor deposition (LPCVD) process where diethylsilane (DES) and nitrous oxide (N₂O) were used as precursor gases. A counterflow reactant geometry was used where the precursor gases were flowed on both sides of the porous membrane. This deposition geometry gave higher selectivities and better mechanical stability. …