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An Experimental Investigation Of 4-Layer Printed Circuit Board Decoupling, Todd H. Hubing, Thomas Van Doren, Fei Sha, James L. Drewniak, Michael J. Wilhelm Aug 1995

An Experimental Investigation Of 4-Layer Printed Circuit Board Decoupling, Todd H. Hubing, Thomas Van Doren, Fei Sha, James L. Drewniak, Michael J. Wilhelm

Electrical and Computer Engineering Faculty Research & Creative Works

This paper examines the measured power bus impedance of fully populated 4-layer printed circuit boards with internal power and ground planes. Three boards provided by two leading computer companies were evaluated. Each of the state-of-the-art high-speed boards used in this study employed surface-mount decoupling capacitors to reduce noise on the power bus. The boards were measured with and without some or all of their decoupling capacitance. The effectiveness of the decoupling capacitors as a function of location and frequency and the relationship between board impedance and power bus noise was explored. The behavior of 4-layer boards is shown to be …


Acuta Enews July 1995, Vol. 24, No. 7 Jul 1995

Acuta Enews July 1995, Vol. 24, No. 7

ACUTA Newsletters

In This Issue

Board report

President's message

Wiring today for tomorrow

Card technology

DC at a glance

From ACUTA Headquarters


Impulse, Stacie Johnson, Cathy Nelson, Cindy Price, Jennifer Widman Jul 1995

Impulse, Stacie Johnson, Cathy Nelson, Cindy Price, Jennifer Widman

Impulse (Jerome J. Lohr College of Engineering Publication)

Features:
[Page 2-4] College of Engineering impact felt throughout the state
[Page 5] Welding binds SDSU with community, industry
[Page 6] Engineering students create moving sign
[Page 7] Galipeau devises new humidity sensor
[Page 7] Alumnus heads engineering building project
[Page 8] South Dakota’s space involvement highlighted at Space Day
[Page 9] Grad students coordinate Space Grant Consortium balloon project
[Page 10] Andrawis, Flippin spend summer researching at NASA
[Page 11] Landscape architect wins summer faculty fellowship at EROS
[Page 12-13] NASA funds undergraduate research assistantships
[Page 14] Volga student assists ACE Camp
Departments:
Faculty:
[Page 15] Engineering professor Ritchie …


Acuta Enews July 1995, Vol. 24, No. 7 Jul 1995

Acuta Enews July 1995, Vol. 24, No. 7

ACUTA Newsletters

In This Issue

Board report

Presidents message

Wiring today for tomorrow

Card technology

DC at a glance

From ACUTA Headquarters


Generalized Beam Matrices: Gaussian Beam Propagation In Misaligned Complex Optical Systems, Anthony A. Tovar, Lee W. Casperson Jul 1995

Generalized Beam Matrices: Gaussian Beam Propagation In Misaligned Complex Optical Systems, Anthony A. Tovar, Lee W. Casperson

Electrical and Computer Engineering Faculty Publications and Presentations

A novel 3 × 3 transfer-matrix method is developed to propagate off-axis Gaussian beams in astigmatic optical systems that may include tilted, displaced, or curved optical elements. Unlike in a previous generalized ray matrix formalism, optical elements that possess gain or loss such as Gaussian apertures, complex lenslike media, and amplifiers are included; and a new beam transformation is found. In addition, a novel exponential variable-reflectivity mirror, which displaces a Gaussian beam without changing its spot size, and a complex prismlike medium are introduced.


Acuta Enews June 1995, Vol. 24, No. 6 Jun 1995

Acuta Enews June 1995, Vol. 24, No. 6

ACUTA Newsletters

In This Issue

Board report

President's message

Charles Co. Community College's telecommuting project

Brock's campus ID card

From ACUTA Headquarters


Bulletin - June, 1995, Civil Aviation Medical Association Jun 1995

Bulletin - June, 1995, 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.


Photovoltaic Applications For Disaster Relief. 11-95. Copies 1, 2&3., Florida Solar Energy Center, William Young Jun 1995

Photovoltaic Applications For Disaster Relief. 11-95. Copies 1, 2&3., Florida Solar Energy Center, William Young

FSEC Energy Research Center®

No abstract provided.


Design, Fabrication, Modeling, And Testing Of Surface-Micromachined Micromirror Devices, M. Adrian Michalicek Jun 1995

Design, Fabrication, Modeling, And Testing Of Surface-Micromachined Micromirror Devices, M. Adrian Michalicek

Theses and Dissertations

The Flexure-Beam Micromirror Device (FBMD) is a phase-only piston style spatial light modulator demonstrating properties which can be used for phase adaptive- corrective optics. This thesis presents a complete study of new designs of FBMDs and other micromirror devices, from original design considerations through final device testing and verification of ideal and advanced models. The models relate the electrical and mechanical properties of the device by equating the electrostatic force of a parallel- plate capacitor with the counteracting spring force of the device's support flexures. For the advanced model of the Flexure-Beam micromirror device, the capacitor solution is derived via …


Finite Element Simulation Of Elastic Wave Propagation In Porous Rock Media, Ahmed Kamal Kamel Jun 1995

Finite Element Simulation Of Elastic Wave Propagation In Porous Rock Media, Ahmed Kamal Kamel

Archived Theses and Dissertations

No abstract provided.


Investigation Of Hybrid Message-Passing And Shared-Memory Architectures For Parallel Computer : A Case Study : Turbonet, Xi Li May 1995

Investigation Of Hybrid Message-Passing And Shared-Memory Architectures For Parallel Computer : A Case Study : Turbonet, Xi Li

Dissertations

Several DSP (Digital Signal Processing) algorithms are developed for the MIT TurboNet parallel computer. In contrast to other parallel computers that implement exclusively in hardware either the message-passing or the shared-memory communication paradigm, or employ distributed shared-memory architectures characterized by inefficient implementation of the shared-memory paradigm, the hybrid architecture of TurboNet supports direct, efficient implementation of both paradigms. Three versions of each algorithm are developed, if possible, corresponding to message-passing, shared-memory, and hybrid communications, respectively. Theoretical and experimental comparisons of algorithms are employed in the analysis of performance. The results prove that the hybrid versions generally achieve better performance than …


Biodegradation Of Mixed Wastes : Basic Kinetics And Reaction Engineering For Cyclic Reactor Operation, Kung-Wei Wang May 1995

Biodegradation Of Mixed Wastes : Basic Kinetics And Reaction Engineering For Cyclic Reactor Operation, Kung-Wei Wang

Dissertations

This study dealt with the determination of the detailed kinetics of the biodegradation of mixed substrates by pure cultures, and with reaction engineering studies of bioreactors employed in treatment of substitutable substrates under cyclic operation.

In the first part of the study the degradation of phenol and 4-chlorophenol (4-CP) by two strains of Pseudomonas species was investigated. Strain P. putida 0 was found to be capable of utilizing both phenol and 4-CP as sole carbon and energy sources. This suggests that this strain follows the ortho-cleavage pathway for the aromatic ring. Strain P. putida N could grow on phenol, and …


Modeling The Fate Of Volatile Organic Compounds In Wastewater Treatment Facilities; Implementation Of Volatilization Models In Envirocad, Vinita Chhahira May 1995

Modeling The Fate Of Volatile Organic Compounds In Wastewater Treatment Facilities; Implementation Of Volatilization Models In Envirocad, Vinita Chhahira

Theses

The 1990 Clean Air Act Amendments have identified wastewater treatment facilities as a major source of volatile organic compound (VOC) emissions. VOCs present in wastewater discharges affect the quality of receiving waters, while emissions to the air affect downwind populations. The primary mechanisms involved in VOC removal from a wastewater treatment facility are volatilization and stripping, biodegradation, and sorption to either suspended or biological solids. Although many models have been developed to predict the fate of VOCs in wastewater treatment facilities, no model completely predicts emissions for an entire wastewater treatment facility. The focus of this work is to incorporate …


Integration Of Pneumatic Fracturing And In Situ Vitrification In Coarse Grained Soils, Sean Thomas Mcgonigal May 1995

Integration Of Pneumatic Fracturing And In Situ Vitrification In Coarse Grained Soils, Sean Thomas Mcgonigal

Theses

This thesis investigates conceptual integration of the Pneumatic Fracturing (PF) process with In Situ Vitrification (ISV) for remediation of contaminated soil. Integration will permit ISV melts to be initiated below the ground surface and extend the depth of the ISV process.

Bench scale experiments were conducted in 4.9 ft3 (0.14 m3) Plexiglas tanks filled with a test soil that was specifically blended to simulate the Hanford Formation in Richland, WA. Discrete pneumatic fractures were successfully created and filled with the ISV starter path material. Conductivity measurements made across two graphite electrodes exhibited a pre-fracture soil resistance of …


Time Dependence Of Multiply Scattered Diffuse Ultrasound In Polycrystalline Media, Joseph A. Turner, Richard L. Weaver May 1995

Time Dependence Of Multiply Scattered Diffuse Ultrasound In Polycrystalline Media, Joseph A. Turner, Richard L. Weaver

Department of Engineering Mechanics: Faculty Publications

Time domain results are presented for the multiply scattered longitudinal intensity backscattered from a polycrystalline medium. The results are solutions to the ultrasonic radiative transfer equation (URTE), the derivation of which is based upon radiative transfer theory. Unlike steady-state solutions obtained previously, time domain solutions will more closely correspond to experiments that use tone burst sources. This paper is concerned with the time dependence of the backscattered longitudinal intensity from a polycrystalline medium excited by a normally incident longitudinal wave idealized as an impulsive deposition of energy. It is shown that multiple scattered effects become significant at times on the …


First Line Supervisor Perceptions: The Effectiveness Of Specific Safety Training Materials, Cynthia Houlson May 1995

First Line Supervisor Perceptions: The Effectiveness Of Specific Safety Training Materials, Cynthia Houlson

Graduate Research Papers

The problem of this study was to determine whether first line supervisors, who have been exposed specifically to Safety Focus Topics, perceived them as an effective tool in filling their role as a safety trainer.


Acuta Enews May 1995, Vol. 24, No. 5 May 1995

Acuta Enews May 1995, Vol. 24, No. 5

ACUTA Newsletters

In This Issue

Board report

President's message

DC at a glance

Benchmarks for your telecom operation

From ACUTA Headquarters


Spatial Variability And Error Limits Of Reference Evapotranspiration Estimates, Thomas W. Ley May 1995

Spatial Variability And Error Limits Of Reference Evapotranspiration Estimates, Thomas W. Ley

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The overall objective of this research was to develop a methodology for assessing the spatial variability and error limits of reference evapotranspiration (ETr) estimates from a weather station network. Likely errors introduced into ETr estimates due to sensor measurement variability and nonstandard site conditions were investigated. Temporal and spatial correlation structures of the weather variables used to compute ETr and of ETr data collected over a three-year period by an operational agricultural weather station network were studied.

Results indicated that ETr errors are minimal compared to inherent model error when sensors (of the type …


On Primitive Bch Codes With Unequal Error Protection Capabilities, Robert H. Morelos-Zaragoza, Shu Lin May 1995

On Primitive Bch Codes With Unequal Error Protection Capabilities, Robert H. Morelos-Zaragoza, Shu Lin

Faculty Publications

Presents a class of binary primitive BCH codes that have unequal-error-protection (UEP) capabilities. The authors use a previous result on the span of their minimum weight vectors to show that binary primitive BCH codes, containing second-order punctured Reed-Muller (RM) codes of the same minimum distance, are binary-cyclic UEP codes. The values of the error correction levels for this class of binary LUEP codes are estimated.


Power Bus Decoupling On Multilayer Printed Circuit Boards, Todd H. Hubing, James L. Drewniak, Thomas Van Doren, David M. Hockanson May 1995

Power Bus Decoupling On Multilayer Printed Circuit Boards, Todd H. Hubing, James L. Drewniak, Thomas Van Doren, David M. Hockanson

Electrical and Computer Engineering Faculty Research & Creative Works

Guidelines for the selection and placement of decoupling capacitors that work well for one-sided or two-sided printed circuit boards are not appropriate for multilayer boards with power and ground planes. Boards without internal planes take advantage of the power bus inductance to help decouple components at the higher frequencies. An effective decoupling strategy for multilayer boards must account for the low inductance and relatively high capacitance of the power bus.


Improved Finite Analytic Methods For Solving Advection-Dominated Transport Equation In Highly Variable Velocity Field, Wei Cuifeng Apr 1995

Improved Finite Analytic Methods For Solving Advection-Dominated Transport Equation In Highly Variable Velocity Field, Wei Cuifeng

Dissertations and Theses

Solute transport studies frequently rely on numerical solutions of the classical advection-diffusion equation. Unfortunately, solutions obtained with traditional finite difference and finite element techniques typically exhibit excessive numerical diffusion or spurious oscillation when advection dominates, especially when velocity field is highly variable.

One recently developed technique, the finite analytic method, offers an attractive alternative. Finite analytic methods utilize local analytic solutions in discrete elements to obtain the algebraic representations of the governing partial differential equations, thus eliminating the truncation error in the finite difference and the use of approximating functions in the finite element method. The finite analytic solutions have …


Improving Operational Readiness Of Airport Emergency Response Crews: Utilization Of Gaming Theory In Decision Making Simulations, William E. Vines Jr. Apr 1995

Improving Operational Readiness Of Airport Emergency Response Crews: Utilization Of Gaming Theory In Decision Making Simulations, William E. Vines Jr.

Master's Theses - Daytona Beach

The purpose of this study was to evaluate the potential effects of simulation gaming technique on the decision-making skills of airport emergency response technicians. Through the use of descriptive research methods this study has examined the benefits of using simulation training to enhance operational readiness. A specialized questionnaire was developed using a Likert scale format to attain the opinion of 20 airport directors--or their representatives. Findings did support the research hypothesis that the introduction of simulation training (Table Top) exercises would increase the operational readiness of airport emergency response crews. Statistical analysis of survey responses found that no significant difference …


Seismic Response On Full-Size Pile Group, Y. C. Han, G. C. W. Sabin Apr 1995

Seismic Response On Full-Size Pile Group, Y. C. Han, G. C. W. Sabin

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

Seismic response of pile group is investigated in both theory and experiment. The dynamic experiments were conducted on a full-size pile group in linear vibration and nonlinear vibration respectively, and the impedances of group were determined using the boundary zone model with non-reflective interface. The theoretical and experimental results indicate that the response of pile group may be increased substantially with the nonlinearity of soil-pile system in a seismic event, and there is a pronounced increase in the horizontal seismic response of group with the pile-soil-pile interaction.


Consistent Infinitesimal Finite-Element Cell Method: In-Plane Motion, John P. Wolf, Chongmin Song Apr 1995

Consistent Infinitesimal Finite-Element Cell Method: In-Plane Motion, John P. Wolf, Chongmin Song

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

To calculate the unit-impulse response matrix of an unbounded medium for use in a time-domain analysis of medium-structure interaction, the consistent infinitesimal finite-element cell method is developed. Its derivation is based on the finite-element formulation and on similarity. The limit of the cell width is performed analytically yielding a rigorous representation in the radial direction. The discretization is only performed on the structure-medium interface. Explicit expressions of the coefficient matrices for the in-plane motion of anisotropic material are specified. In contrast to the boundary-element formulation, no fundamental solution is necessary and equilibrium and compatibility on the layer interfaces extending from …


Elasto-Plastic Seismic Response Analysis Of Earth Dams, A. N. Yiagos Apr 1995

Elasto-Plastic Seismic Response Analysis Of Earth Dams, A. N. Yiagos

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

A simplified and efficient numerical model is developed to perform the phenomenological elasto-plastic seismic response analysis of earth dams. The method is based on a two-dimensional Galerkin formulation of the equations of motion for the dam material, and accounts for the presence of water inside the dam. The soil skeleton nonlinear hysteretic response is modelled using an effective stress multi-yield function elasto-plastic constitutive model. The model is validated using actual transient ground motions as input and the computed responses are compared with the motions recorded at the respective sites. The ability of the model to simulate the occurrence of liquefaction …


R-Wave Dispersion Analysis In Transversely Isotropic Stratum, Shiming Wu, Lizhong Wang Apr 1995

R-Wave Dispersion Analysis In Transversely Isotropic Stratum, Shiming Wu, Lizhong Wang

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

With dynamic stiffness of elastic half-space, the Rayleigh wave dispersion in transversely isotropic soil is analyzed by Finite-layer and Semi-infinite layer method. Only is matrix eigenvalue involved, avoiding the calculation procedure encountered in analytical method. Two examples prove the deduction correctly and show that soil anisotropy influences dispersion dramatically. It is possible to study soil anisotropy and characteristics of its dynamical responses from its surface wave dispersion.


Clay Behavior, Ground Response And Soil-Structure Interaction Studies In Mexico City, Miguel P. Romo Apr 1995

Clay Behavior, Ground Response And Soil-Structure Interaction Studies In Mexico City, Miguel P. Romo

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

This paper focuses on the most relevant results of recent investigations carried out on the behavior of Mexico City clays under dynamic loading, on the effects of soil site conditions and on the evaluation of the dynamic soil-structure interaction phenomenon. The paper shows the impact of these studies upon foundation engineering practice in earthquake-prone regions where clayey deposits exist, and advances simple, yet accurate, procedures to develop site-dependent, building-specific input motions for the design of structures in the Valley of Mexico. It discusses recent seismic observations that clarify the origin of the long coda observed in several records obtained in …


Seismic Design Of Pile Foundations: Structural And Geotechnical Issues, Geoffrey R. Martin, Ignatius Po Lam Apr 1995

Seismic Design Of Pile Foundations: Structural And Geotechnical Issues, Geoffrey R. Martin, Ignatius Po Lam

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

Research on soil-pile-structure interaction under dynamic loading over the past 20 years has led to a variety of analysis approaches of varying complexity to address a range of dynamic problems. Many of these analysis approaches have been adapted for use for the seismic design of pile foundations. In this paper, the various analysis methods are only briefly reviewed. The focus of discussion is on design concepts and issues more routinely used or encountered by structural engineers during seismic design of new or retrofitted pile foundation systems representative of those used for bridges and buildings.


Third International Conferences On Recent Advances On In Geotechnical Earthquake Engineering And Soil Dynamics, Multiple Authors Apr 1995

Third International Conferences On Recent Advances On In Geotechnical Earthquake Engineering And Soil Dynamics, Multiple Authors

International Conference on Case Histories in Geotechnical Engineering

No abstract provided.


Dynamic Characteristics Of Comares Palace In The Alhambra, V. Cuellar, E. Kausel, J. L. Monte, J. M. Roesset, J. Valerio Apr 1995

Dynamic Characteristics Of Comares Palace In The Alhambra, V. Cuellar, E. Kausel, J. L. Monte, J. M. Roesset, J. Valerio

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

This paper describes the geotechnical investigations that have been conducted to characterize the static and dynamic properties of the ground, the foundation and the structure's material of the Comares tower in the Alhambra palace. The Gmax values of the different materials were determined using seismic refraction, P-wave transmission tomography, cross-hole and down-hole tests. To obtain the variation of the shear moduli with strain amplitude surface wave and cyclic horizontal plate loading tests were performed in several trenches excavated in the immediate neighborhood. The analysis of the structure response to M = 5 earthquakes recently recorded at the top and …