Engineering Commons^™

Design And Development Of Microswitches For Micro-Electro-Mechanical Relay Matrices, Mark W. Phipps

Theses and Dissertations

Many different micro-electro-mechanical switches were designed in the Multi-User MEMS processes (MUMPs) and deep x-ray lithography and electroforming (LIGA) processes. The switches were composed of actuators that operated based upon either electrostatic forces or thermal forces. A thermally activated beam flexure actuator that operated based upon differential heating was used extensively. This actuator, which was fabricated in the MUMPs process, was able to deflect up to 12 microns with a total input power of less than 25 mW. The thermal resistance, which was needed to model this actuator, was determined from a material constant, 1.9 ± 0.08 m^1.5-°C-W …

A Comparative Study Of The Stress Concentration Factors Arising Between Two Equal, Nearly Intersecting, Perpendicular, Pressurized Holes In An Infinite Solid With Those Arising Due To An Infinite Series Of Such Holes, Paul J. Drogowski

Masters Theses

Finite element analysis is used to determine the stress concentration factors arising from two equal, perpendicular, nearly intersecting, pressurized holes in an infinite solid while varying the distance and pressure ratios between the holes. The results are compared and contrasted with those previously obtained for an infinite series of such holes. A ratio of the distance between the holes to the diameter of the holes at which the holes can be considered to be single holes in an infinite solid is determined. A study is performed to determine a correlation between the location of the region of maximum stress and …

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

Archived Theses and Dissertations

No abstract provided.

Reduction Of Lead Pollution From Vehicular Emissions In Greater Cairo, Sherif Kamal Saleh

Archived Theses and Dissertations

No abstract provided.

Composite Beam Analogy Fracture Model (Cbafm) : A Non-Linear Fracture Mechanics Model For Concrete, Mohammed Enamul Haque

Dissertations

The main objective of this dissertation is to develop a simple non-linear fracture mechanics model for the determination of fracture mechanics parameters for concrete, such as fracture process zone length (rp), critical fracture energy release rate (Gic), critical stress intensity factor (KO and fracture energy (GF). The fracture process zone (FPZ) is modeled as a damaged non-elastic cohesive band where the extent of damage due to microcracking varies from no damage at the boundary of FPZ to complete crack surface separation at the notch or macro-crack tip. The proposed method can predict theoretically both the pre-peak and post-peak load versus …

Grain-Size Optimization And Scheduling For Distributed Memory Architectures, Jing-Chiou Liou

Dissertations

The problem of scheduling parallel programs for execution on distributed memory parallel architectures has become the subject of intense research in recent, years. Because of the high inter-processor communication overhead in existing parallel machines, a crucial step in scheduling is task clustering, the process of coalescing heavily communicating fine grain tasks into coarser ones in order to reduce the communication overhead so that the overall execution time is minimized.

The thesis of this research is that the task of exposing the parallelism in a given application should be left to the algorithm designer. On the other hand, the task of …

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

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 …

Analysis Of A Design For Its Quality Manufacturability In Terms Of Misalignments And Fastener Related Problems, Abhinav Dhar

Theses

This study analyzes the relationship between design parameters established at the initial stage of the design process and the manufacturing quality problems that manifest themselves during production. Specifically, we study the relationship between design features and the occurrence of misalignment defects and fastener related problems.

This outcome of this work is a methodology, Design for Quality Manufacturability (DFQM). DFQM addresses the likelihood that defects will occur during the manufacture of a product in a standard plant. This is based on the premise that defects in assembled products are often influenced by some features of the design and/or assembly process. These …

The Morphology Of Uhmwpe Wear Debris Generated By A Hip Joint Simulator, Aaron P. Essner

Theses

The size, quantity and shape of total hip replacement wear debris may identify wear mechanisms as well as play a role in osteolysis. Characterization of wear particles generated from a hip joint simulator was conducted followed by comparison with literature reported in vivo results. The effect of counterface material and lubricant type on particle morphology was assessed. Biomaterial pairs including UHMWPE articulated against CoCr, Alumina and Zirconia were considered. Deionized (D.I.) water and bovine serum were used as lubricants. Particles generated from Alumina/UHMWPE in serum were slightly larger than those for CoCr and Zirconia against UHMWPE in serum. Particle shape …

A Study Of Transit Corridors Within The Njtpa Region, Mark Kagen Berger

Theses

Identifying potential bus and rail transit corridors for the North Jersey Transportation Planning Authority (NJTPA) region by examining current travel patterns of commuters was the purpose of this thesis. The current transit corridors within the NJTPA region was discussed first, followed by the methods for selecting specific municipalities for analysis. At this point, specific examinations of the selected municipalities' origin and destination travel patterns were mapped. The results were then summed up, along with a discussion of potential new bus and rail transit corridors based on trips originating along a corridor enroute to the same municipality. The final discussion examined …

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 …

A Modified Lrt-Based Spread-Spectrum Receiver Using Spatial And Temporal Processing, Jeffrey L. Cutcher

Theses

The problem of demodulating a direct-sequence (DS) spread-spectrum signal in the presence of single-tone or narrow-band interference and multi-path is discussed. A likelihood-ratio test (LRT) receiver is presented which consists of a whitening filter and a RAKE correlator.

A modified LRT receiver structure is then considered where the whitening filter is replaced by an antenna array with corresponding tap coefficients. The array spatially removes the interference by estimating it's angle-of-arrival. Using the array has an advantage over the original LRT receiver when a narrow-band interference is present. Both receivers are identical in performance under the single-tone interference model.

A third …

Hydrodynamic And Water Quality Modeling Of The Whippany River, John E. Krohn

Theses

The Whippany River is located in northern New Jersey and is a major tributary to the Passaic River System. This waterway accepts a wide variety of wastes from the diverse communities within its watershed. These wastes contribute to a rather complex network of biological, chemical and physical interactions.

The purpose of this study is to develop a water quality model using QUAL2E. This model will be used as a tool to simulate the complex interactions that take place within the river system. The river must he considered from physical, biological and chemical perspectives. A successful model can determine current water …

Effects Of Ergonomic Worksite Changes On Risks For Cumulative Trauma Disorders Of The Upper Body In An Assembly And Press Operation Job, David B. Mahone

Theses

Cumulative trauma of the upper body is associated with a variety of individual and job factors. An effort to optimize the human-hardware interface to minimize cumulative trauma is favored. Workers in a set of jobs had complained about hand/wrist and shoulder discomfort. One job was selected for testing alternate machine controls and worksite layout. Electromyography was used to test muscle activity, and photogoniometry was used to measure posture.

For the group of ten worker-subjects, statistically significant decreases in hand/wrist and shoulder muscle activity were found. A marginal, but significant increase in neck muscle activity was also found. When one subject …

Fundamentals Of Adhesion Of Organic Compounds And Aqueous Cleaning Of Glass And Metal Surfaces : Applications In The Pharmaceutical And Chemical Industries, Michel J. De Ruijter

Theses

In this thesis we studied the physics and chemistry of the adhesion of various classes of organic compounds to glass and stainless steel surfaces, by using diagnostic aqueous cleaning solutions and other techniques. We defined the thermodynamic requirements for aqueous cleaning based on extensive experimental and theoretical work. Novel cleaning diagrams are introduced, based on electrostatic interactions between organic compounds and solid surfaces, to facilitate the design of aqueous cleaning systems. We studied the mass transfer parameters for selected situations. The electrochemical Pourbaix-diagrams were used to explain the effect of hydrogen peroxide added to aqueous solutions and to avoid corrosion …

Radiation Damage Studies In Gate Oxides, Sandeep G. Bharathi

Theses

Detailed investigation of the effects of Gamma-ray irradiation on the electrical properties such as current-voltage arid capacitance-voltage characteristics in thermally grown SiO₂ films in the thickness range of 15 to 120 nm on silicon substrates is presented in this thesis. The structures used in this study are Al/Poly/SiO₂/Si/Al and Al/SiO₂/Si/Al MOS capacitors. Based on the electrical characterization studies, we observe that irradiation causes generation of positive charges in the oxide leading to a shift of the high frequency Capacitance-Voltage (C-V) curves. An increase in surface state density at the SiO₂-Si interface with increase …

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 …

Application Of Signal Processing Techniques For Measurement Of Muscle Fiber Conduction Velocity, Satheesh Kumar Swaminathan

Theses

The objectives of this study were to evaluate if muscle fiber conduction velocity (MFCV) could be used as a reliable indicator of fatigue and to characterize the recovery of MFCV after a fatiguing contraction. The decline of MFCV with fatigue was modelled using linear regression and compared with the decline in median frequency (MF). It was found that the percent decline in MF with fatigue was greater than that of MFCV with fatigue and that the decline of MFCV was consistent in all subjects tested. It was thus determined that MFCV could be used as a reliable indicator of fatigue. …

Reducing Rail-Truck Freight Intermodal Drayage Costs, David Moy Jr.

Theses

In rail-truck intermodal transport, a highway truck-trailer or container is moved by truck from a shipper to a rail terminal in the shipper's vicinity, and by rail in line haul between rail terminals. Upon being unloaded at the destination rail terminal, the container is delivered to a receiver (consignee) by truck. The highway portion of the move, or drayage, accounts for a relatively high percentage of total origin to destination cost, and it limits severely the competitiveness of intermodal service with door-to-door truck service. The approach used in this thesis is to examine in detail the current costs and potential …

A Defect Detection Algorithm For Sequential And Parallel Computers, Ralf Hross

Theses

The comparison of images containing a single object of interest, where one of them contains a model object, is frequently used for defect detection/identification. This is often a problem of interest to industrial applications. To make this task more efficient, the implementation on parallel computers should be a major objective. This thesis introduces sequential and parallel versions of an algorithm that compares original(reference) and processed images in the time and frequency domains. The emphasis is on parallel implementation. This comparison may help to detect changes in images. Extracted data is also compared to database data in an attempt to pinpoint …

Effect Of Fiber-Matrix Coupling On The Mechanical Properties Of A Totally Bioabsorbable Composite, Barbaro Jesus Perez

Theses

The mechanical properties of a new class of bioabsorbable polymer-composite based on the amino acid tyrosine and calcium phosphate fibers were studied. The effect of the fiber aspect ratio on the elastic modulus of a discontinuous fiber composite was analyzed using the SMC composite micromechanics computer model. The mechanical stiffness of this polymer was found to be superior to that of poly-p-dioxanone, caprolactone and poly-o-ester.

The fiber surface was modified with methane plasma spray to improve the fiber-matrix coupling. The treated fiber composites had 16-40% higher tensile modulus than the untreated fiber composites. From the flexural test results it is …

A Comparison Of Anhydrous Ethanol Production From Ethylene And From Corn Utilizing Life Cycle Analysis Methodology, Gregory Morse

Theses

There is currently much concern with the impact on the environment due to industrial processes. One method to assess this impact is to perform a Life Cycle Analysis (LCA) on the process. Life Cycle Analysis is made up of three stages; Life Cycle Inventory Analysis, Life Cycle Impact Assessment, and Life Cycle Improvement Assessment. In this study, Life Cycle Inventory Analysis methodology was applied to two industrial processes for producing anhydrous ethanol. The first process is the fermentation of corn, and the second is the hydration of ethylene using water and a catalyst. Each process was first modeled using the …

A Vhdl Design Of A Reconfigurable Cache Memory System, Tiffany M. Brooks

Honors Capstone Projects and Theses

No abstract provided.

Testability Design And Testability Analysis Of A Cube Calculus Machine, Lixin Zhou

Dissertations and Theses

Cube Calculus is an algebraic model popular used to process and minimize Boolean functions. Cube Calculus operations are widely used in logic optimization, logic synthesis, computer image processing and recognition, machine learning, and other newly developing applications which require massive logic operations. Cube calculus operations can be implemented on conventional general-purpose computers by using the appropriate "model" and software which manipulates this model. The price that we pay for this software based approach is severe speed degradation which has made the implementation of several high-level formal systems impractical. A cube calculus machine which has a special data path designed to …

Water Quality Model For South Slough, Coos Bay, Oregon, Holly Kay Juza

Dissertations and Theses

The South Slough Estuary is located off Coos Bay along the southern coast of Oregon. It is divided into two channels that meet and continue to Coos Bay at the Charleston Harbor. There are six major contributing streams to South Slough. After rainfall events, the level of coliform bacteria in the slough increases because of stream bacteria loading. This is due to cattle grazing in the drainage areas, failed septic systems from private homes, and sewage sludge applied to the County landfill, which drains into the slough. The Oregon Health Division has enforced a Sanitation Management Plan for Commercial Shellfish …

Bandwidth And Additive Bandwidth Of Graphs, Maria Kujawski

Honors Capstone Projects and Theses

No abstract provided.

Numerical Study Of Granular Soil Behavior Using Random Arrays Of Elastic Ellipsoids, Xiaoshan Lin

Civil Engineering ETDs

For the purpose of improving computer simulation of granular materials in the framework of the Discrete Element Method (DEM), 2-D and 3-D discrete element models using random arrays of elastic ellipsoids have been developed.

The Effects Of A Pathway-In-The-Sky Display On Performance Of A Two Axis Tracking Task By Instrument Rated Pilots, Leonard W. Hennessy, Iii

Master's Theses - Daytona Beach

This study was founded on the premise that airplane cockpit operations, while generally safe and relatively efficient, can be made even more so by employing instrument displays which are potentially more intuitive than existing displays. A low fidelity flight simulator was used to conduct an experiment comparing the performance of twenty-four instrument rated pilot subjects on a two axis tracking task (an Instrument Landing System Approach) under three instrument display conditions: (1) conventional instruments (INST); (2) a Pathway-in-the-Sky (PITS) display; and (3) a combination of the two (BOTH). The primary hypothesis, that pilot performance using the PITS and BOTH display …

Dynamic Simulation Of General Aviation Cabin Environments And Occupant Restraint Systems, Mark A. Shilladay

Master's Theses - Daytona Beach

After a five year study of General Aviation (GA) accidents, the National Transportation Safety Board (NTSB) has concluded that aircraft cabin environments place the occupant at high risk of suffering severe injuries in an emergency crash situation. Studies of Federal Aviation Administration (FAA) seat tests were used to form the basis of a computer analysis to address dynamic cabin environments. In this effort a simplified system of masses, springs, and dampers are used to simulate the more complex configuration of cabin structure, seat, pilot, and restraints on a personal computer. The primary objective of this study is to accurately simulate …