Engineering Commons^™

A Report On County Road Program Finance (Fiscal Year 1995-96), Patsy Anderson, Kris Hockensmith

Kentucky Transportation Center Research Report

This report reflects the findings of a study of county road finance in Kentucky. Statistics contained in the report were derived from financial statements submitted by the counties to the Kentucky Department of Local Government.

Fuzzy Based Forebody Vortex Flow Controller For The X-29a Aircraft, Jin Suzuki

Masters Theses

This paper demonstrates the development and performance of A Fuzzy Logic based regulator for an aircraft which is equipped with pneumatic forebody Vortex Flow Controller at high angle-of-attack flight condition. The VFC provides the pilot additional control power at flight conditions where conventional effectors such as rudder and differential flaps lose effectiveness.

Fuzzy Logic Control (FLC) is applied to a mixed bang-bang and conventional type control system. This unique configuration ensures robustness of the system and simplifies the controller design. Performance of the FLC based regulator shows a 10.3% reduction in cost function compared to the system controlled by a …

A Toolkit For Specializing Production Operating System Code, Crispin Cowan, Dylan Mcnamee, Andrew P. Black, Calton Pu, Jonathan Walpole, Charles Krasic, Perry Wagle, Qian Zhang

Computer Science Faculty Publications and Presentations

Specialization has been recognized as a powerful technique for optimizing operating systems. However, specialization has not been broadly applied beyond the research community because the current techniques, based on manual specialization, are time-consuming and error-prone. This paper describes a specialization toolkit that should help broaden the applicability of specializing operating systems by assisting in the automatic generation of specialized code, and {\em guarding} the specialized code to ensure the specialized system continues to be correct. We demonstrate the effectiveness of the toolkit by describing experiences we have had applying it in real, production environments. We report on our experiences with …

Behavior Of Web Elements With Openings Subjected To Linearly Varying Shear, Matthew R. Eiler, Roger A. Laboube, Wei-Wen Yu

CCFSS Library (1939 - present)

PREFACE An experimental investigation of the shear buckling limit state was conducted on single web, cold-formed steel flexural members with web openings. The purpose of the investigation was to develop a better understanding of the behavior of web elements having a web opening, and to propose appropriate design recommendations based on the observed behavior. The present AlSI ASD and LRFD specifications do not contain design provisions for webs with openings, thus the findings of this study will aid in enhancing the shear design provisions. The test specimens, constructed from C-sections, were subjected to linearly varying shear resulting from the application …

An Efficient Technique For Evaluating The Modal Parameters Of Damped Dynamic Systems, Hany Jim Gross

Archived Theses and Dissertations

No abstract provided.

Design, Simulation, Fabrication And Testing Of Microprobes For A New Mems Wafer Probe Card, Yanwei Zhang

Dissertations

A new type of MEMS cantilever wafer probe card consists of an array of microcantilevers individually actuated by bimorph heating to make contact with the test chip was designed and fabricated. This probe card is called the CHIPP (Conformable, High-Pin count, Programmable ) card and can be designed to contact up to 800 I/O pads along the perimeter of a 1 cm² chip with a microprobe repeat distance of ~50 µm. Each microcantilever had an internal heater and a separate electrode carrying the signal under test and contained four separate layers plus a fifth material for the contact tip …

Design Fabrication And Characterization Of High Performance In Gaas/Inp Focal Plane Array In The 1-2.6 Μm Wavelength Region, Krishna R. Linga

Dissertations

This research thesis describes a new In_xGa_1-xAs/InA_ysP_1-y/InP technology for long wavelength photodetectors and photodetector arrays. A unique and novel detector structure was designed and fabricated using Hydride Vapor Phase Epitaxy, for low leakage current photodetector arrays in the 1-2.6 µm wavelength region. Potential applications of InGaAs focal plane arrays include near-infrared spectroscopy, fluorescence, remote sensing, environmental sensing, space and astronomical applications. The unique design concepts included the step grading of InAsP layers, lower lattice mismatch between the two InAsP graded layers, lattice matched InAsP cap layer and InGaAs absorption layer, sulphur doping …

The Design And Fabrication Of A Thermal Microprobe Integrated On An Atomic Force Microscope Probe Tip, Yongxia Zhang

Dissertations

A thermal microprobe has been designed and built for high resolution temperature sensing. The thermal microprobe consists of a very-thin-film thermocouple junction confined to the very end of a low mass Atomic Force Microscope (AFM) probe tip. Essential to high resolution temperature sensing is the confinement of the thermocouple junction to a short distance at the AFM tip. This confinement is achieved by controlled photoresist coating.

Experimental prototypes have been made with the junction confined to within 0.3 µm of the tip. The couple is made of Au/Pd, and the two metals are electrically separated elsewhere by a thin insulating …

Distribution Of Velocities And Velocity Gradients In Mixing And Flocculation Vessels : Comparison Between Ldv Data And Cfd Predictions, Changgen Luo

Dissertations

Flocculation is an operation of significant industrial relevance commonly encountered in many processes, including water and wastewater treatment. The physico-chemical phenomena of this process is strongly affected by the magnitude of the velocity gradients generated, typically through agitation, in rapid mix devices and flocculation vessels.

In this work the fluid dynamic characteristics of mechanically agitated systems, namely three different types of stirred tanks, which can be used as flocculation vessels, were studied. Both the mean and fluctuating velocities in all three directions were measured by using a Laser-Doppler Velocimeter (LDV). The velocity distribution, fluctuating velocities, power consumption and local velocity …

Adaptive Space-Time Processing For Digital Mobile Radio Communication Systems, Amit Shah

Dissertations

The performance of digital mobile radio communication systems is primarily limited by cochannel interference and multipath fading. Antenna arrays, with optimum combining (OC), have been shown to combat multipath fading of the desired signal and are capable of reducing the power of interfering signals at the receiver through spatial filtering. With OC, the signals received by several antenna elements are weighted and combined to maximize the output signal-to-interference-plus-noise ratio (SLNR). We derive new closed-form expressions for (1) the probability density function (PDF) of the SINR at the output of the optimum combiner, (2) the average probability of bit error rate …

Multi-Wavelength Pyrometric Systems For Emissivity-Independent Non-Contact Temperature Sensing, Michael B. Kaplinsky

Dissertations

A Multi-Wavelength Imaging Pyrometer (M-WIP) for real-time remote sensing of temperature profiles of targets with unknown emissivity was developed and demonstrated. To measure the spectral radiance of a target at several distinct wavelengths an M-WIP system was implemented based on an 320x122-element PtSi IR-CCD imager with an assembly of 7 narrow-band 1k filters in the range from 1790nm to 4536nm. A real-time algorithm for simultaneous estimation of the temperature and model parameters of the target emissivity from the least-squares fit of the theoretical model of 1k camera output signal to the experimental spectral measurements was developed and implemented. This rea1-time …

Development Of A Mathematical Model Of Gait Dynamics, Tae Ho Choi

Dissertations

There exists hypothesis that gait selection is strongly correlated with mechanical energy efficiency in normal subjects. The hypothesis is experimentally proven, and intuitively taken for granted. However, it is not mathematically proven that the minimum energy consumption hypothesis is the underlying principle for the normal human gait. To prove the hypothesis we have developed a mathematical model of human walking, in which it is possible to predict an optimal gait at any given speed of walking based on the principle of minimum mechanical energy consumption.

This improved model, which includes the double-support phase of walking as well as the swing …

Particle Deposition From Turbulent Flow In A Divergent Channel, Wai-Ting Huang

Dissertations

This dissertation presents a numerical analysis of particle deposition from a dilute gas-solid two-phase suspension in a divergent channel. The Lagrangian governing equations for particle motion include inertia force, viscous force, gravity force and image force from electrostatic charge on the particle. The incompressible two-dimensional turbulent flow field in a divergent channel is solved by employing a Κ-ε modeling technique with FIDAP finite element CFD software. A computational procedure is developed to incorporate the flow field into numerical simulation of particle trajectories from which the fraction of deposition is determined. Several divergent channels (half divergent angles of 0°, 7.5°, 10° …

Scheduling In Assembly Type Job-Shops, Nutthapol Asadathorn

Dissertations

Assembly type job-shop scheduling is a generalization of the job-shop scheduling problem to include assembly operations. In the assembly type job-shops scheduling problem, there are n jobs which are to be processed on in workstations and each job has a due date. Each job visits one or more workstations in a predetermined route. The primary difference between this new problem and the classical job-shop problem is that two or more jobs can merge to foul' a new job at a specified workstation, that is job convergence is permitted. This feature cannot be modeled by existing job-shop techniques. In this dissertation, …

Motion Compensation And Very Low Bit Rate Video Coding, Shu Lin

Dissertations

Recently, many activities of the International Telecommunication Union (ITU) and the International Standard Organization (ISO) are leading to define new standards for very low bit-rate video coding, such as H.263 and MPEG-4 after successful applications of the international standards H.261 and MPEG-1/2 for video coding above 64kbps. However, at very low bit-rate the classic block matching based DCT video coding scheme suffers seriously from blocking artifacts which degrade the quality of reconstructed video frames considerably. To solve this problem, a new technique in which motion compensation is based on dense motion field is presented in this dissertation.

Four efficient new …

Performance Optimization Of Very High Frame Rate Ccd Burst-Image Sensors, Zeynep M. Pektas

Dissertations

The primary objective of this work was to demonstrate the feasibility of an image sensor that is capable of capturing images at 10⁷ frames per second. Such high frame rate operation is based on storage of a certain (N) number of frames into the BCCD memory registers and readout at a slower rate at the end of the frame collection period. To accommodate an optical frame time of 100ns, a high-speed virtual-gate photodetector with six multiple n-type implants was proposed and a novel design strategy was developed. The feasibility of this design was demonstrated by simulating the entire photodetector …

Modeling Of 3d Swept Volumes Using Sde/Sede Methods And Its Application To Five-Axis Nc Machining, Liping Wang

Dissertations

This research falls in two important areas in solid modeling and manufacturing automation: (1) swept-volume modeling; (2) computer-based NC (Numerically controled) machining simulation and verification. The swept volume is defined as the volume swept by an object undergoing an arbitrary motion. Modeling of 3D swept volumes includes the boundary computation and representation of a swept volume generated by a general object undergoing general motion in three dimensional space. The Sweep Differential Equation (SDE) and Sweep Envelope Differential Equation (SEDE) methods are two of the important swept volume modeling methods employed in this dissertation. They exploit differential equations to obtain the …

Membrane-Based Reactors For Ozonolysis Of Organic Pollutants In Aqueous And Gaseous Streams, Purushottam V. Shanbhag

Dissertations

Many gaseous and aqueous waste streams contain multiple organic pollutants at low concentration levels. It is not economical to recover and reuse these compounds; it would be advantageous to destroy them efficiently within the waste stream. This work employed ozone, a powerful oxidizing agent, in concert with a compact membrane-based phase-contacting device. Three types of membrane devices were studied: two of them (the single-phase membrane ozonator and the two-phase membrane ozonator) treated organic pollutants in wastewater, while the third (the integrated absorption-oxidation membrane ozonator) removed volatile organic compounds (VOCs) from a gaseous waste stream.

In the single-phase membrane ozonator, the …

The Fatigue Problems Of Cracks Subjected To Obliquely Incident Stress Waves, I-Chung Weng

Dissertations

Catastrophic failure of aircraft and other structures are often caused by undetected cracks. Fracture mechanics has been developed to augment traditional static and fatigue design. In the static theory of fracture mechanics, extensive treatment has been given to the stress distribution around sharp cracks and notches under various loading conditions. Previous works on the problems of dynamic loadings are not accurate in dealing with singularities at high frequencies. The numerical solutions become unrealistic at high frequencies in many practical applications.

To address the need to obtain the stress intensity factor in high frequency dynamic loading situations, we studied the use …

Analysis Of 320x240 Uncooled Microbolometer Focal Plane Array And Design Of Thermoelectric Cooler Controller, Takayoshi Fukaya

Theses

Uncooled microbolometer focal plane array is one of the promising method used in uncooled infrared imaging projects. The array's advantages over the conventional cooled imagers are its ability to operate without cryogenic cooler or dewar and its low cost. For the past several years, the ULTRA (Uncooled, Low cost, Technology Reinvestment Alliance) Consortium has been developing uncooled microbolometer imaging system.

This thesis investigates the technology behind the ULTRA camera system. The theoretical as well as the operation of the uncooled microbolometer focal plane array and the processing hardware and software is analyzed and explained.

Thermoelectric cooler controller for the microbolometer …

Growth Of Grass Shrimp, Palaemonetes Pugio, In A Contaminated And An Uncontaminated Site, Suruchi Bhan

Theses

Previous experiments have found that grass shrimp, Palaemonetes pugio, from a contaminated site, Piles Creek (PC). in Linden. New Jersey, are larger than those from a relatively pristine reference site, Sheepshead Creek, located in Tuckerton (T), New Jersey.

This study investigated the possibility that PC conditions provide more food for the shrimp, possibly by being a eutrophic environment. thus allowing for greater growth. or that salinity, toxicants, or other factors at. PC stimulate growth. The current experiment indicated that PC conditions do not foster greater growth for the shrimp than T conditions and that PC shrimp are not inherently …

An Investigation Into The Feasibility Of Utilizing Pneumatic Ultrasonic Devices Coupled With Pneumatic Fracturing In Enhancing Removal Of Volatile Organic Compounds From Soils, Hugo J. Fernandez

Theses

A bench scale investigation was conducted in a Plexiglass ™ Test cell 1 foot square by 2 feet in height, packed with 400 mesh sand to a density of 100 lb. /ft³. The sand was contaminated with a mixture of 10% ethanol and 90% water by weight having a total weight of 11.1 pounds, before it was packed in the test cell. A geotextile 1/2 inch thick was used as a simulated fracture and was placed 3 inches from the bottom of the tank. A siren and a whistle were tested in this fracture.

The data were divided …

Equivalent Circuit Analysis Of A Seventh Order Bandpass Loudspeaker System, Michael Gunnar Johnson

Theses

A seventh order bandpass loudspeaker system was designed using an equivalent circuit analysis. The electrical, mechanical and acoustic systems were each modeled as separate subcircuits derived by using a Voltage-Force-Pressure or impedance analogy; the interactions between the subcircuits were modeled using coupled controlled-sources. The equivalent circuit was analyzed using SPICE (Simulation Program with Integrated Circuit Emphasis). A technique for modeling port and cavity resonances inside the enclosure using distributed element approximations for the resonant components was developed and verified by measurement.

A complete microcomputer based experimental loudspeaker testing system was designed incorporating a sweep frequency oscillator, a gain-controlled audio power …

Analysis Of Surface Texture Parameters And Cutting Forces In Milling Operations, Preetesh U. Munshi

Theses

It has been known and understood that milling is quite a complicated process being a multi-point cutting tool operation. Each Surface texture is complex and requires different functions of forces to get the optimized Surface Texture. The challenge faced here is to devise any form of relation between the Surface Texture and the Milling Operating parameters (Spindle Speed, Feed rate, Depth of Cut), Cutting forces and the Milling Operating parameters and also between the Surface Texture and the Cutting Forces.

This Research study was conducted to determine the effect of the Operating Parameters on Surface Texture and Cutting forces and …

The Relationship Between Thermoregulatory And Haemodynamic Responses Of The Skin To Relaxation And Stress, Paul O. Nketia

Theses

The present study investigated the effects of stress and relaxation on (1) EEG coherence and (2) peripheral blood flow.

EEG coherence of two meditators in two different but adjacent rooms was measured during eyes opened, eyes closed, single meditation and group meditation. The skin temperatures of the subjects together with their room temperatures were also recorded. EEG coherence plots (Cospar) showed a spread out of the alpha band to the beta, theta and occasionally to the delta wave bands during group meditation. The area above the 0.98 coherence threshold in the alpha band was greater during group meditation than during …

Petri Net Modeling And Performance Analysis Of Z39.50 Search And Retrieval Protocol, Roopali Paranjpe

Theses

Z39.50 is an American Standard for information retrieval. The standard depicts a client-server model of computing. With reference to the Open System Interconnection (COSI)) model developed by International Standards Organization (ISO); Z39.50 is an application layer protocol. A Z39.50 client performs searching, querying and requesting functions and a Z39.50 server interfaces with the database in the remote system and responds to client requests by providing a set of records for the search query.

Z39.50 state tables describe a complex set of concurrent and serial events. A Petri net model is prepared for the entire system comprising the protocol. A Petri …

Low Pressure Chemical Vapor Deposition Of Silicon Carbonitride Films From Tri(Dimethylamino) Silane, Rajive Shah

Theses

A literature study to investigate the incorporation of silicon into SiC and Si₃N₄ films from various organosilanes was carried out. The Arrhenius activation energy for the synthesis of silicon, silicon carbide and silicon nitride films from various organosilanes range from 165-210 kJ/mol. A review of recent studies have indicated that silicon deposition is the rate determining step in the synthesis of silicon from silane. It is proposed here that this hypothesis can be established for the synthesis of silicon carbide, silicon nitride and silicon carbonitride film. Limited experiments indicated that the silicon deposition is a rate determining …

Parameters' Analysis Of 3d Random Stacking Palletization, Najeeb Syed

Theses

Palletization is a very important element of production, distribution and warehousing activities. The 3D random stacking palletization method is based on volume utilization instead of surface area optimization. Random stacking provides interlocking among the boxes and hence it improves the stability of the pallet load. Volumetric Pallet Utilization is normally the prime concern of any palletization process, with Work in Process and Palletization time being also important. This research uses data generated from a previous heuristic to establish mathematical relationships between the three mentioned performance indices and also three additional indirect variables, namely: Total Number of Sub Volumes, Partitioned Remaining …

Decontamination Of Aquifers Via Air Sparging/Biofiltration : An Experimental Study, Armando Mora Tellez

Theses

In this study experiments were performed in order to show feasibility of an integrated air sparging/biofiltration process for cleaning contaminated groundwater. Feasibility was also meant in the sense of meeting regulatory constraints. Using toluene as model compound and changing flowrates for the sparged air, it was shown that despite fluctuations in the toluene concentration at the inlet of the biofilter, the concentrations at the outlet of the unit were essentially constant over long periods of time and remained below the levels dictated by environmental regulations. However an increase in outlet concentrations at levels not meeting regulatory constraints was observed after …

Renin-Angiotensin System And Its Relationship To Arterial Pressure Regulation, Sami D. Saume

Theses

The renal system is known to participate in the natural regulation of blood pressure. A renal system model that simulates interaction responses of renal output to arterial blood pressure was developed. The major components of this model are glomerular filtration rate, tubular sodium reabsorption, the renin-angiotensin system, Aldosterone secretion, and antidiuretic hormone secretion. The model's differential equations were coded using Vissim 1.2 student version. It was found that, the renal output increased as glomerular filtration rate, Aldosterone concentration, and blood pressure increased. Conversely, increasing antidiuretic hormone concentration lead to decreased renal output.

Additionally, Angiotensin II and Aldosterone concentrations increased as …