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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 …


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 …


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 …


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 …


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 …


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 …


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 …


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. …


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, …


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 …


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 …


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, …


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 …


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 …


Analysis And Comparison Of Resistive, Ferroelectric And Pyroelectric Uncooled Bolometers For Electronic Imaging Systems, Mo-Huang Li May 1997

Analysis And Comparison Of Resistive, Ferroelectric And Pyroelectric Uncooled Bolometers For Electronic Imaging Systems, Mo-Huang Li

Theses

The performance parameters (responsivity (Rv). detectivity (D*), total noise and response time) of resistive, pyroelectric and ferroelectric bolometer detectors are dependent on a large number of key variables including chopping frequercy, the input impedance and voltage noise of the readout circuitry, the structure dependent parameters (particularly thermal conductance and thermal capacitance), and material properties such as dielectric constant, pyroelectric coefficient, loss tangent and thin film thickness. The interrelationship between the key variables and their influence on performance is often complex and not easily discerned for the three major types of thermal detectors: resistive, pyroelectric and ferroelectric bolometers.

In …


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 …


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 …


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 May 1997

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 …


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 …


Mechanical Evaluation Of Pedicle Screw Fixation Of The Lumbar Spine, Ding Lu May 1997

Mechanical Evaluation Of Pedicle Screw Fixation Of The Lumbar Spine, Ding Lu

Theses

Pedicle screw fixation of the lumbar spine has been reported to increase fusion rates A biomechanical evaluation of four different pedicle screw implant systems, (AO. Rogozinski, TSRH and Wiltse). was performed to compare intrinsic device stiffness under conditions of flexion-compression and forty-five degree off-axis flexion-compression The effect on stiffness of the loosening of device members was also studied. Testing was done in load control using an electrohvdrualic testing machine. UHMWPe blocks are used to simulate the vertebra.

Assuming that stiffness is directly proportional to the probability of obtaining fusion. this study allows the ranking of the systems tested in their …


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 …


Parameters' Analysis Of 3d Random Stacking Palletization, Najeeb Syed May 1997

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 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 …


The Study Of Permeability In Concrete, Jie Yuan May 1997

The Study Of Permeability In Concrete, Jie Yuan

Theses

In this study, samples of regular, high performance, expansive and the polymer concrete and mortar were prepared for test of permeability and mechanical property. In the permeability measurement, water and an aqueous chemical solution were employed as the permeant.

The test results of the samples, ranging from 5.7 x 10-9 cm/sec to 1.0 x cm/sec for the permeability and 3800 psi to 10600 psi for compression strength, indicated that the polymer coated concrete has the lowest permeability among the concretes and high performance concrete has the highest compression strength . The finding leads to the possibility that a high strength …


An Analytical Approach To Toxic Substance Replacement In Support Of Pollution Prevention, Ithan B. Zimmer May 1997

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

Theses

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

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


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 …