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A Decision Support System For The Equipment Selection Of Robotic Manufacturing Cells, Lars Johan Resare Oct 1997

A Decision Support System For The Equipment Selection Of Robotic Manufacturing Cells, Lars Johan Resare

Theses

Considering the principles of concurrent engineering, a Decision Support System (DSS) is developed to aid in the equipment selection of robotic manufacturing cells. The objective is to synchronously and simultaneously select proper equipment for the cell to provide efficient performance, subject to operational and budgetary constraints.

The DSS consists of several modules, including a data base that houses the specifications of equipment available in the market place, a first cut selection module, and an optimization engine. In its development, the optimization scheme utilizes analytical models and algorithms that capture different sources of variability in production, such as tolerances, clearances and …


Electrophysiologic Studies Of Hypothalamic Adenosine-5'-Triphosphate-Sensitive Potassium Channels, Dinora Hernandez Oct 1997

Electrophysiologic Studies Of Hypothalamic Adenosine-5'-Triphosphate-Sensitive Potassium Channels, Dinora Hernandez

Theses

Of particular interest in this study were the electrical phenomena involving currents from the ATP sensitive K channel in isolated hypothalamic ventromedial nucleus (VMN) neurons. These neurons may play an important role in the glucose-sensing system of the body. Rat VMN neurons were isolated. For neuronal isolation, the proteolytic enzyme pronase was used. However, pronase was too harsh. The use of papain, another proteolytic enzyme, led to better neuronal morphology. The perforated patch clamp technique was used to gain access to the cell's interior. For membrane pore formation, nystatin was used; but seal formation was difficult. Amphotericin was used instead, …


Soot Capture In An Electrocatalytic Reactor, Thana Slanvetpan Oct 1997

Soot Capture In An Electrocatalytic Reactor, Thana Slanvetpan

Theses

A major problem with many soot emission control devices is the fact that they quickly become loaded with soot which must be removed by a regeneration process. A soot capture reactor using a large flow channel was studied in order to eliminate channel plugging and avoid regeneration. Electrostatic precipitation was used in order to enhance particle diffusion to the catalyst wall of the reactor tube. The system effectiveness for soot capture was measured with filter paper sampling of the incoming versus the outgoing flow through the reactor. Soot filter loadings were analyzed by laser optical transmission. From the soot filter …


Mechanical Design Of An Experimental Parallel Robot, Philip Song Oct 1997

Mechanical Design Of An Experimental Parallel Robot, Philip Song

Theses

OSCAR, or Operational Space Controlled Adjustable Robot, is a parallel-actuated manipulator, also known as Stewart Platform or platform manipulator. The apparatus consists of two platforms (base and top) and six prismatic actuators in between. The main advantage of a platform manipulator is the fact that it can out-perform serial manipulators in both load capacity and precision. However, there are disadvantages and weaknesses such as limited mobility. A platform manipulator has reduced workspace compared to serial manipulators. The problem of limited workspace is solved by enabling OSCAR to change its prismatic leg positioning about the base platform.

During the course of …


Synthesis And Characterization Of Phosphosilicate Glass Films By Lpcvd For Sensor Application, Hui Wu Oct 1997

Synthesis And Characterization Of Phosphosilicate Glass Films By Lpcvd For Sensor Application, Hui Wu

Theses

This study was dedicated to the synthesis of the thin film materials required to fabricate the waveguide and the reference arm barrier for integrated optical sensor. Phosphosilicate glass (PSG) thin films were synthesized on silicon and quartz wafers by LPCVD using Ditertiarybutylsilane(DTBS), Trimethylphosphite(TMP) and oxygen as precursors. The films were processed at different temperatures between 600°C and 700°C at a constant pressure, and at different flow rate of TMP.

The effect of TMP flow rate and deposition temperature on deposition parameters and the properties of PSG films were investigated. The films deposited were uniform, amorphous, low stress and the composition …


Determination Of Effects Of Stress On Polymeric Ankle-Foot Due To Weight Change: Experimental Stress Analysis, Lin Yu Wang Oct 1997

Determination Of Effects Of Stress On Polymeric Ankle-Foot Due To Weight Change: Experimental Stress Analysis, Lin Yu Wang

Theses

Ankle-Foot Orthoses (AFOs) are devices that assist patients who sustained an abnormal motion at the ankle joint of the foot due to traumatic injury and stroke, etc. The objective of this project is to determine the stress patterns in AFOs under different loading conditions such as weights and genders. Thus, the location of failure can be predicted, and a redesign process can be developed. Furthermore, those experimental results will be used to verify the results obtained from the previous Finite Element Analysis (FEA) [11,10]. Results from the experiment showed a significant stress change due to load change. This stress …


Using Heart Variability To Measure The Effects Of Manual Medicine On Autonomic Activity, Michael Zullow Oct 1997

Using Heart Variability To Measure The Effects Of Manual Medicine On Autonomic Activity, Michael Zullow

Theses

A pilot study was performed to test the theory that manual medicine techniques known as the CV4 (compression of fourth cerebral ventricle) maneuver and a sacral hold/iliac bridge hold combination increase parasympathetic activity. Manual medicine techniques are widely practiced by Doctors of Osteopathy and Chiropractors to treat physical and mental health problems. Those who have received manual therapy have reported to experience less pain, better mobility, and a greater feeling of relaxation. To help us learn about the effects of manual therapy, autonomic activity was measured scientifically rather than subjectively in this study by monitoring respiration rate and heart rate, …


Pervaporation-Assisted Esterification Of Salicylic Acid, Chaiya Chandavasu Oct 1997

Pervaporation-Assisted Esterification Of Salicylic Acid, Chaiya Chandavasu

Theses

The coupling of a pervaporation membrane unit with a reactor has been investigated as a means of improving the overall process efficiency. As model system, the esterification of salicylic acid with methanol in the presence of a homogeneous catalyst was studied in a unit consisting of a batch reactor externally coupled with a pervaporation module containing a composite poly(vinyl alcohol) membrane. The reaction was carried out at temperatures between 336 and 345 K. The catalyst was sulfuric acid at concentrations varying from 0.5 to 2.0 molar. Various initial molar ratios (ΘB) of methanol and salicylic acid, ranging from …


Multi-Lifecycle Assessment Of Cathode Ray Tubes, Devendra Jayant Badwe Oct 1997

Multi-Lifecycle Assessment Of Cathode Ray Tubes, Devendra Jayant Badwe

Theses

Over the past few years environmental issues and concerns have become more and more important, as they become a common part of most people's personal experience. In these regards, the electronics industry is facing substantial problems in terms of end-of-life management of its products, televisions and monitors in particular. The building blocks of this industry are usually viewed as relatively "clean". However, manufacturing by-products of the electronics industry and the disposition of electronics are becoming increasingly important technical, financial, and environmental issues.

Within the context of the above issues, environmentally responsible disposal of Cathode Ray Tubes (CRT's), which is still …


Biodegradation Of Naphthalene Using Pseudomonas Putida (Atcc 17484) In Batch And Chemostat Reactors, Jay Boyd Best Oct 1997

Biodegradation Of Naphthalene Using Pseudomonas Putida (Atcc 17484) In Batch And Chemostat Reactors, Jay Boyd Best

Theses

Kinetic experiments were conducted using Pseudomonas putida (ATCC 17484) to determine the rate of growth when naphthalene was provided as a sole carbon source in suspended biomass systems. Batch and chemostat reactors were used under three sets of conditions: non-aerated, aerated at 29.5° C, and aerated at 25.5° C. A number of concentrations were tested under each set of conditions. Data regression was used to determine parameters for Monod (non-inhibitory), Andrews (inhibitory), and zero-order kinetics. Although the Andrews fit of the data provided a slightly lower sum-of-squares error (SSE), the amount of data scatter and the weak inhibition made the …


Development Of Aqueous Scrubber To Oxidize And Absorb Nitric Oxide, Wanna Lolertpiphop Oct 1997

Development Of Aqueous Scrubber To Oxidize And Absorb Nitric Oxide, Wanna Lolertpiphop

Theses

The use of sodium chlorite (NaClO2) and alkaline aqueous cumene hydroperoxide (CHP) as oxidizing agents to promote the absorption of nitric oxide from flue gases was investigated in a semicontinuous bubbling scrubber. The efficiency of the scrubbing solutions to remove nitric oxide was evaluated as a function of operating conditions such as pH, concentration of the oxidants, residence time, temperature, flue gas compositions.

Under acid conditions, sodium chlorite can stoichiometrically react and absorb 99.5% NO and 80% SO2 in the same scrubber with 0,672 M NaClO2 in buffered solution at pH 6, and 0.3 M NaOH. …


Computational Determination Of Laminar Flow Loss Coefficients In 90° Channel Bend, Leonard Paul Parkin Oct 1997

Computational Determination Of Laminar Flow Loss Coefficients In 90° Channel Bend, Leonard Paul Parkin

Theses

Loss coefficients for laminar two dimensional incompressible channel (or duct) flow in a 90° bend are investigated using FEM software, FIDAP. This problem consists of a two dimensional duct with a 90° bend of constant radius flowing with water, at 70°F and atmositeno conditions. The bend radius to duct width ratios examined were 1.5 and 1.0. Both bend radius to duct width ratios were analyzed for Reynolds Number ranging from 50 to 1800. The pressure and velocity distributions were found and used to determine the pressure due to the bend. The results show the pressure loss effect due to the …


Microstrip Zero-Sum Antenna; Cad And Experimental Study, Tuan H. Lam Oct 1997

Microstrip Zero-Sum Antenna; Cad And Experimental Study, Tuan H. Lam

Theses

A microstrip antenna array consisting of two elements combined with a stripline hybrid (rat-race) ring coupler is used to implement a zero-sum antenna. Numerical optimization of individual antenna elements in terms of feed location and patch size was achieved using IE3D (Zeland Software Inc., Fremont, CA), a fullwave 3-D planar electromagnetic simulation software. Further, design of a hybrid (rat-race) ring coupler in a stripline environment was carried out, yielding the sum and difference functions as 0.5 dB and 40 dB, respectively. A combination of a two-element antenna array and a hybrid (rat-race) ring coupler as a zero sum antenna has …


Mixed Metal Removal And Recovery By Hollow Fiber Membrane-Based Extractive Adsorber, Ramprakash Chilukuri Oct 1997

Mixed Metal Removal And Recovery By Hollow Fiber Membrane-Based Extractive Adsorber, Ramprakash Chilukuri

Theses

The feasibility and efficiency of simultaneous removal of multiple cations as well as anionic heavy metals from wastewater into a mixed extractant kept stagnant on the shell side of a 2-fiber-set hollow fiber membrane extractor operated as a fixed bed adsorber was explored. The novel extracting solvent was a mixture of an acidic or chelating extracting agent for one or more cations and a basic extracting agent, e.g., trioctylamine (TOA) for extracting anions; both were dissolved in the same diluent kerosene for simultaneous and synergistic extraction of cations and anions. In the stripping part of the fixed bed operation, alkaline …


Modeling Of Deformed Swept Volumes With Sde And Its Applications To Nc Simulation And Verification, Feng Lu Oct 1997

Modeling Of Deformed Swept Volumes With Sde And Its Applications To Nc Simulation And Verification, Feng Lu

Theses

Representation of swept volumes has important applications in NC simulation and verification as well as robot-motion planning. Most research on .the representation of swept volumes has been limited to rigid objects. In this study, a sweep deferential equation (SDE) approach is presented for the representation of deformed swept volumes generated by flexible objects.

The deformed swept volume analysis is integrated with machining physics to account for tool deformation/deflection for the NC simulation. End milling is modeled and analyzed and the tool deformations are calculated and integrated with the SDE program. A program is developed in C++ for the generation of …


Characteristics Of Recycled Plastics And Applications For Highway Appurtenances, Keith Macbain Oct 1997

Characteristics Of Recycled Plastics And Applications For Highway Appurtenances, Keith Macbain

Theses

Recycling is gaining widespread support in many communities as an environmentally acceptable solution to the management of solid waste. The success of these recycling programs depends largely on the development of high-value end use for the recycled products. This research involves an experimental and analytical study on the development of high-value, high-volume end uses for recycled plastic shapes. The experimental part includes material tests to determine mechanical properties of various recycled plastics. A constitutive model is proposed and verified that can be used in characterization of recycled plastics. Bending tests of recycled plastic beams were performed to assess strength, stiffness …


The Relationship Between Thermoregulatory And Haemodynamic Responses Of The Skin To Relaxation And Stress, Paul O. Nketia May 1997

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 …


Computer Simulation Of Cerebrovascular Circulation : Assessment Of Intracranial Hemodynamics During Induction Of Anesthesia, Steven D. Wolk May 1997

Computer Simulation Of Cerebrovascular Circulation : Assessment Of Intracranial Hemodynamics During Induction Of Anesthesia, Steven D. Wolk

Theses

The purpose of this project was to develop a computer model of cerebrovascular hemodynamics interacting with a pharmacokinetic drug model to examine the effects of various stimuli during anesthesia on cerebral blood flow and intracranial pressure.

The mathematical model of intracranial hemodynamics is a seven compartment constant volume system. A series of resistances relate blood and cerebrospinal fluid fluxes to pressure gradients between compartments. Arterial, venous, and tissue compliance are also included. Autoregulation is modeled by transmural pressure dependent arterial-arteriolar resistance. The effect of a drug (thiopental) on cerebrovascular circulation was simulated by a variable arteriolar-capillary resistance. Thiopental concentration, in …


Petri Net Modeling And Performance Analysis Of Z39.50 Search And Retrieval Protocol, Roopali Paranjpe May 1997

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 …


Decontamination Of Aquifers Via Air Sparging/Biofiltration : An Experimental Study, Armando Mora Tellez May 1997

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 …


Analysis Of 320x240 Uncooled Microbolometer Focal Plane Array And Design Of Thermoelectric Cooler Controller, Takayoshi Fukaya May 1997

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 …


Equivalent Circuit Analysis Of A Seventh Order Bandpass Loudspeaker System, Michael Gunnar Johnson May 1997

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 …


Heat Transfer Enhancement From A Heat Pipe Immersed Horizontally In Water, Under Natural Convection Conditions, With The Aid Of Gas Injection, Evangelos J. Minakas May 1997

Heat Transfer Enhancement From A Heat Pipe Immersed Horizontally In Water, Under Natural Convection Conditions, With The Aid Of Gas Injection, Evangelos J. Minakas

Theses

An experimental study has been performed to estimate the degree of heat transfer enhancement from a horizontal heat pipe, immersed in water with the aid of air injection. This thesis investigates the effects of different shroud shapes, shroud distances from the heat pipe, air injection rates, air injection configurations and air injection distances on the augmentation of heat transfer. Water was the experimental fluid and its temperature ranged from 17-60 °C, the surface temperature of the heat pipes varied from 18-75 °C.

It was discovered that the shape of the shrouds is a contributing factor on the heat transfer enhancement. …


Enhancing The Bioavailability Of Sorbed Pollutants From Sediments Using Ultrasound, Rachel Mathew May 1997

Enhancing The Bioavailability Of Sorbed Pollutants From Sediments Using Ultrasound, Rachel Mathew

Theses

Many organic compounds, that enter aquatic systems have a strong tendency to sorb onto particulate matter which may be present in suspension or as sediment. Numerous studies have shown that the sediment in aquatic systems concentrate contaminants several orders of magnitude greater than the concentration in the aqueous phase. Particulate associated contaminants in sediments are not easily bioavailable. Hence the efficacy of any treatment technology would be strongly undermined if the contaminants are not made available for microbial utilization. Sediment associated contaminants can be made biologically available to various microorganisms under certain conditions.

In this study, desorption studies were conducted …


Finite Element Analysis Of Skin Injuries By Water Jet Cutting, Syed Muhammad Arif May 1997

Finite Element Analysis Of Skin Injuries By Water Jet Cutting, Syed Muhammad Arif

Theses

High pressure water jets are used in industry for cleaning and cutting purposes. These devices can generate pressure up to 400 MPa. As high pressure water jets become more widespread in industry, injuries will be seen with great frequency. Penetrating injuries by these devices can produce minimal external evidence of extensive soft tissue injury. To know the extent of injury, it is important to study the relationship between operating parameters of water jet and the skin layers. A computational analysis is carried out using finite element method to find the effects of water jet pressure on the skin layer. Finite …


Determination And Studying Of Stress Distribution In Various Ankle-Foot Orthoses : Experimental Stress Analysis, Rong Feng May 1997

Determination And Studying Of Stress Distribution In Various Ankle-Foot Orthoses : Experimental Stress Analysis, Rong Feng

Theses

Ankle-Foot Orthosis (AFO) is prescribed to constrain and inhibit abnormal motion such as "drop foot" due to stroke. Most orthoses were hand-made by orthotists according to their own experience. However, some types of AFO were easy to fatigue (out of their functional capabilities) than others due to regular usage. In order to improve the design and usage, quantitative stress analysis of different types of orthoses is needed. The objective of this project is to obtain experimental data which will confirm the results obtained from previous Finite Element Analysis (FEA)[1]. In addition, the experimental analysis is extended to obtain …


Design Improvement Using Reverse Analysis In Design For Quality Manufacturability, Vikram V. Datla May 1997

Design Improvement Using Reverse Analysis In Design For Quality Manufacturability, Vikram V. Datla

Theses

The competitive needs of modern manufacturing demands that innovative approaches be used to gain an edge over the competitors. least Product design is one of the key dimensions wazzu in which companies can excel. Shortening the product design cycle so as to rapidly launch defect free products, is the goal of most companies. Design for Quality Manufacturability (DFQM) is a technique used to evaluate the quality manufacturability of a product at the design stage, so as to eliminate quality problems during production.

DFQM provides a means for relating the activities of quality improvement, product design and manufacturability analysis. The basis …


Low Frequency Characterization Of A Loop Antenna, Irene Koukhta May 1997

Low Frequency Characterization Of A Loop Antenna, Irene Koukhta

Theses

The conventional solution of an integral equation for the loop antenna in free space can be expressed analytically using Fourier Series. However, the solutions based on delta gap feed model yield divergent input susceptance.

To overcome such diverging results, alternative solution using equivalent magnetic frill current feed models were implemented. Although low frequency models for delta gap feeds were suggested, no generalized low frequency expansions for the input admittance have been reported previously. In this work, such generalized low frequency expansion are developed for both delta-gap and magnetic frill feeds of loop antennas. Validity of such expansion have been investigated …


Analysis Of Surface Texture Parameters And Cutting Forces In Milling Operations, Preetesh U. Munshi May 1997

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 …


Renin-Angiotensin System And Its Relationship To Arterial Pressure Regulation, Sami D. Saume May 1997

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 …