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Trifluoroiodomethane As An Environmentally Friendly Gas For Water Patterning By Plasma Etching Process, Krit Aryusook Jan 1997

Trifluoroiodomethane As An Environmentally Friendly Gas For Water Patterning By Plasma Etching Process, Krit Aryusook

Theses

Trifluoroiodomethane (CF3I), a non-global warming gas, has been investigated with study as a substitute for typical CFC etchants, such as CF4 and C2F6, used in wafer pattering technology. This investigation was carried out by exposing dielectric films of silicon oxide (SiO2) and silicon nitride (Si3N4) in CF3I and C2F6/O2 (used as a reference) plasma environments. The etch rate of these films was ascertained as function of applied rf power, etchant gas flow rate, reaction chamber operating pressure, and O2 …


Design Of A Mode Of Delivery For Macrobead Transplantation, Jagdip Desai Jan 1997

Design Of A Mode Of Delivery For Macrobead Transplantation, Jagdip Desai

Theses

The macrobead is a form of a biohybrid artificial pancreas (BAP), which is being developed to treat type 1 diabetes. A hypothetical human transplant would require 125 rat equivalent macrobeads. For intraperitoneal transplantation a mode of delivery that allows the placement of several hundred macrobeads into a basket or pouch type device is required.

In this study, four commercially available materials were studied as possible candidates for creating a pouch. These materials are polyvinyl chloride acrylic copolymer (PVC), polyethersulfone (PES), polyvinylidenedifluoride (PVDF), and polytetrafluorethylene (PTFE). Tubular pouches of each material were designed. They then underwent in vivo biocompatibility and in-vitro …


Abstraction Of An Object-Oriented Vocabulary By Providing A Standardized Interface, Hemant Kothavade Jan 1997

Abstraction Of An Object-Oriented Vocabulary By Providing A Standardized Interface, Hemant Kothavade

Theses

Controlled vocabularies are ubiquitous in varied application fields. They are particularly helpful in the medical field since they can unify disparate terminologies and provide information in a compact, comprehensible manner. In this thesis, we present a mechanism to efficiently retrieve and update knowledge stored in a controlled vocabulary modeled as an Object-Oriented Database (OODB) system. We aim to provide a standardized interface to the vocabulary, such that the implementation details of the vocabulary are transparent to all users. The user of this standardized interface will typically be an application programmer who is trying to provide the vocabulary's knowledge-base to end …


Experimental Investigation Of Collisional Properties Of Spheres, Laurent Labous Jan 1997

Experimental Investigation Of Collisional Properties Of Spheres, Laurent Labous

Theses

We present experimental results on the collisional properties of spheres obtained through high-speed video analysis. An apparatus is built that produces collisions of spheres of various sizes with a wide range of impact, velocities and incidence angles.

Edge detection techniques are implemented to track the position of the spheres from frame to frame whereby the translational velocities may be computed. In order to determine the rotational velocities, small markers are imprinted on the surfaces of the spheres and also tracked and matched from one frame to the next.. From the pre and post collision kinematic data, three collisional properties are …


Synthesis And Characterization Of Hafnium Carbide Thin Films, Wiriya Thongruang Jan 1997

Synthesis And Characterization Of Hafnium Carbide Thin Films, Wiriya Thongruang

Theses

Hafnium carbide thin films of various characteristics were deposited on silicon substrates using dc magnetron sputtering. A HfC target was used as a sputtering source and Ar was used as a sputtering gas during deposition. The variables investigated were total sputtering gas pressure and power. Optimum characteristics were achieved with a total sputtering gas pressure of 5 mTorr and power of 200 W. No evidence for oxidation of the film was found at a depth below 400A for deposited and annealed films. Binding characteristics were obtained from ESCA data. The compressive film stress increased when sputtering gas pressure decreased. The …


Size-Frequency Distribution Of Palaemonetes Pugio In Two New Jersey Estuaries And Predator-Prey Interactions With Fundulus Heterocolitus, Celine Santiago Jan 1997

Size-Frequency Distribution Of Palaemonetes Pugio In Two New Jersey Estuaries And Predator-Prey Interactions With Fundulus Heterocolitus, Celine Santiago

Theses

Predation by Fundulus heteroclitus is known to be an important factor regulating the abundance and size distribution of Palaemonetes pugio in the salt marsh habitat.

A preliminary study showed that P. pugio from a polluted estuary, Piles Creek, were relatively larger than those found in a more pristine estuary, Little Sheepshead Creek. Possible causes could be differences in competition, inherent environmental components, reproductive effort, or predation. To investigate the differences in size frequency, data on relative abundances of both species and size frequency distribution of P. pugio were collected for comparison from the two estuaries.

It was determined that P. …


A Methodology For The Design Of An Integrated Air Stripping/Biofiltration Process To Clean Contaminated Aquifers, Pothitos Ioannis Stamatiadis Jan 1997

A Methodology For The Design Of An Integrated Air Stripping/Biofiltration Process To Clean Contaminated Aquifers, Pothitos Ioannis Stamatiadis

Theses

This thesis deals with the conceptual design of an integrated air stripping/biofiltration process for cleaning aquifers contaminated with volatile organic pollutants. In this technology, the pollutant is transferred from the aquifer to an air stream which is subsequently treated in a biofilter. The work presented here is an effort to develop a design methodology for the integrated process and suggests a general, quantitative approach which can be used in preliminary technology evaluation. This methodology involves relatively simple equations for the stripping process and detailed (oftentimes complex) models for biofiltration under conditions of continuous variation of the properties of the polluted …


Performance Evaluation Of Cebus Power Line Communication In The Presence Of X-10 Module Signaling, Nashwa F. Kamel Jan 1997

Performance Evaluation Of Cebus Power Line Communication In The Presence Of X-10 Module Signaling, Nashwa F. Kamel

Theses

A power line of CEBus has great potential towards inexpensive home automation. Both PLBus and X-10 uses [sic] burst of 120KHz signals to transmit bits of information on the power line. However, these two systems are completely incompatible and can conflict with each other. This thesis presents the first performance evaluation of Power Line CEBus communication in the presence of X-10 module signaling. The evaluation included simulation experiments measuring packet delays, message delays, message throughput, channel throughput and the percentage of messages received in error verses [sic] different loads. Network performance has been confirmed to function well in terms of …


A Cost Model For Multi-Lifecycle Engineering Design, Bin Zhang Jan 1997

A Cost Model For Multi-Lifecycle Engineering Design, Bin Zhang

Theses

Design for Environment aims to yield a product whose aggregate environmental impact is as small as possible. This thesis characterizes a product recovery system and defines the concepts of product lifetime and part lifetime. A multi-lifecycle product recovery model is developed based on the concepts of product tree and disassembly path representation, four product recovery choices, time varying costs, cost comparison. The four product recovery choices of a part in the product tree are: Reconditioning, Part Remanufacturing, Material Recycling, and Landfill. This thesis focuses on how to improve the product design while minimizing environmental impact of the product and introduces …


Measuring The Need For Manufacturing Flexibility And Evaluating Its Economic Benefits, Navin Karwande Jan 1997

Measuring The Need For Manufacturing Flexibility And Evaluating Its Economic Benefits, Navin Karwande

Theses

Flexible systems are known of enabling organizations to take advantage of diversified products, low volume production items with short life-cycles. They also improve the ability to respond to market changes. Flexibility has thus become a strategic manufacturing need in recent years.

Because of the high initial capital outlay involved, the selection of the appropriate flexible solution has become a critical issue. This thesis proposes a methodology to determine the most cost effective and feasible flexibility strategy. A flexibility audit is developed to analyze and evaluate the changes taking place in a facility's environment. These changes and a measurement scheme is …


Oxidative Response Of Immobilized Bovine Blood To The Model Pollutant Phenol, Michael George Nickey Jan 1997

Oxidative Response Of Immobilized Bovine Blood To The Model Pollutant Phenol, Michael George Nickey

Theses

The primary purpose of this work is to determine if bovine blood can be studied in an immobilized cell bioreactor to determine if a phenol induced oxygen releasing optimum exists. This method of study has the potential to be used to determine what effects xenobiotics have on the oxidative activities of blood.

Three blood fractions containing approximately 21, 44, and 70% red blood cells (RBCs) were immobilized and placed in a recirculating bioreactor. These fractions were exposed injections of 0 ml, 3 ml, or 10 ml amounts of 2000 ppm phenol. The most active fraction was the 21% red cell …


Tcp/Ip Traffic Over Atm Network With Abr Flow And Congestion Control, Liping An Jan 1997

Tcp/Ip Traffic Over Atm Network With Abr Flow And Congestion Control, Liping An

Theses

Most traffics over the existing ATM network are generated by applications running over TCP/IP protocol stack. In the near future, the success of ATM technology will depend largely on how well it supports the huge legacy of existing TCP/IP applications.

In this thesis, we study and compare the performance of TCP/IP traffic running on different rate based ABR flow control algorithms such as EFCI, ERICA and FMMRA by extensive simulations. Infinite source-end traffic behavior is chosen to represent, FTP application running on TCP/IP. Background VBR traffic with different ON-OFF frequency is introduced to produce transient network states as well as …


Microporous Silicon Dioxide/Vycor Membranes For Gas Separation, Justin R. Barone Jan 1997

Microporous Silicon Dioxide/Vycor Membranes For Gas Separation, Justin R. Barone

Theses

This study focused on producing membranes for molecular sieving of gases by reducing the pore size of an already existing membrane structure. To do this, SiO2 was deposited inside the pores of a Vycor tube with initial pore diameter of 4 nm. The film deposition took place by a low pressure chemical vapor deposition (LPCVD) process where diethylsilane (DES) and nitrous oxide (N2O) were used as precursor gases. A counterflow reactant geometry was used where the precursor gases were flowed on both sides of the porous membrane. This deposition geometry gave higher selectivities and better mechanical stability. …


Potential Effects Of Pneumatic Fracturing On Existing Structures And Utilities, Michael C. Canino Jan 1997

Potential Effects Of Pneumatic Fracturing On Existing Structures And Utilities, Michael C. Canino

Theses

This thesis develops a mathematical design model for predicting ground deformations resulting from pneumatic fracturing. Pneumatic fracturing is a patented process developed for the purpose of enhancing the in situ treatment and removal of hazardous contaminants from geologic formations. During pneumatic injections, measurable ground deformations are experienced both during and after the process. Safe application of pneumatic fracturing to contaminated plumes occurring beneath existing structures and utilities requires that the elastic deformation behavior of the geologic formation and overlying structures be quantified.

Data from five pneumatic fracturing sites were regressed to establish the characteristic polynomial describing the curvature of ground …


Vibration Control Of Robotic Modules Using Input Shaping Algorithm, Murat Eren Jan 1997

Vibration Control Of Robotic Modules Using Input Shaping Algorithm, Murat Eren

Theses

In this thesis, vibration control using input shaping algorithm is studied. Vibration Control of flexible structures is an important problem and has been an active research area. Different approaches have been developed for vibration control which can be divided roughly into feedback and feedforward methods. Feedback methods need measurements and on-line calculation of the controller outputs. Although feedback methods are generally more robust and have a number of well known performance advantages, proper use of feedforward control can also significantly improve the speed of response of the system.

Input shaping is one of these feedforward methods. It has been successfully …


Design, Simulation And Fabrication Of A Mems In-Situ Contactless Sensor To Detect Plasma Induced Damage During Reactive Ion Etching, Subramanian Ganesh Jan 1997

Design, Simulation And Fabrication Of A Mems In-Situ Contactless Sensor To Detect Plasma Induced Damage During Reactive Ion Etching, Subramanian Ganesh

Theses

The present trend in the semiconductor industry is towards submicron devices. An inevitable process technique in achieving this is by reactive ion etching of the polysilicon gate. During RIE, the gate oxide may get damaged due to several causes. One of the main causes of the damage is the non-uniformity of the plasma. It is reported that these plasma inconsistencies are mainly due to electrode design and that they create spatial plasma potential fluctuation. These fluctuations are reported to be in the range of 10-20 Volts. By providing an in-situ monitoring of the wafers, the reliability of the device could …


Three-Dimensional Stress Analysis Of The Femur With Prosthetic Hip Stem Utilizing Computed Tomography Scans Of The Femur For Geometry And Material Properties, Thomas J. Lavin Jan 1997

Three-Dimensional Stress Analysis Of The Femur With Prosthetic Hip Stem Utilizing Computed Tomography Scans Of The Femur For Geometry And Material Properties, Thomas J. Lavin

Theses

Three-dimensional finite element stress analyses of the femur with prosthesis hip stem were performed for two cases, one male and one female, using ideally bonded cemented titanium prostheses. Computed tomography data files were used to derive the three-dimensional femur geometry and material properties for each cortical bone element. The maximum shear stress (4.7 MPa) in the cement was greater then the maximum tensile stress and occurred at the cement-bone interface. The tensile stresses in the cement were less then the fatigue strength of the cement. The stress patterns were quite similar for the two cases.

A data analysis program was …


Application Of Geometric Hashing Techniques To Retrieval Of High Dimensional Objects In Scientific Databases, Joyce Ye Lu Jan 1997

Application Of Geometric Hashing Techniques To Retrieval Of High Dimensional Objects In Scientific Databases, Joyce Ye Lu

Theses

An approach to designing very fast algorithms for tackling the problem of approximate object matching in very large databases of high-dimensional objects is proposed. Given are a target object C and a database D containing information about a set of high-dimensional objects each of which is represented as a set of points. Our algorithms have an off-line object preprocessing (shape representation) phase and a recognition phase. The described algorithms determine those objects from D which are the closest to object C, according to delete or insert some points, move and rotation. All of these can be achieved very efficiently with …


Optimization Of Ion-Exchange Chromotography With Multiple Gradient Inputs For Protein Separations, Tariq Mahmood Jan 1997

Optimization Of Ion-Exchange Chromotography With Multiple Gradient Inputs For Protein Separations, Tariq Mahmood

Theses

Gradient elution chromatography is an efficient technique for adjusting the retention of sample components during liquid chromatographic separations. However, the optimization of gradient elution is usually done by trial and error. Thus, for large scale processes this results in expensive and time consuming design and operations. Peak resolution that describes the degree of separation is a commonly used parameter for chromatographic processes. However, in processes where operating time and product dilution are of great importance, resolution alone is not adequate for describing the separation efficiency.

A new parameter "resolution optimization factor" is used for the optimization of gradient elution processes. …


Synthesis And Characterization Of Silicon Dioxide Thin Films By Low Pressure Chemical Vapor Deposition, Sutham Niyomwas Jan 1997

Synthesis And Characterization Of Silicon Dioxide Thin Films By Low Pressure Chemical Vapor Deposition, Sutham Niyomwas

Theses

Ditertiarybutylsilane ( DTBS ) and oxygen have been used as precursors to produce silicon dioxide films by low pressure chemical vapor deposition. These films were synthesized in the temperature range of 600°C to 800°C at constant pressure, and at different gas flow composition. The films were found to be uniform with a composition that varied with deposition temperature and gas flow ratio. The growth rate was found to follow an Arrhenius behavior with an apparent activation energy of 2.62 kcal/mol. The growth rate was seen to increase with higher distance between wafers and to vary as a function of square …


Modeling Of Objects Using Planar Facets In Noisy Range Images, Girish Phansalkar Jan 1997

Modeling Of Objects Using Planar Facets In Noisy Range Images, Girish Phansalkar

Theses

Products designed and manufactured before the advent of Computer Aided Design (CAD) and Computer Aided Manufacturing (CAM) technology have not been documented electronically. To avoid the laborious procedure of redesigning the parts, a reverse engineering approach can be adopted. This approach involves, taking a picture of the object and constructing a solid model from the image data.

Range image is a three dimensional image of an object or a scene. This image can be obtained from special cameras, called range image cameras, or can be constructed from the Coordinate Measuring Machine's (CMM) output data. Adaptive Fuzzy c-Elliptotype (AFC) clustering algorithm …


Catalytic Control Of Nitric Oxide With Gaseous Or Solid Reducing Materials, Xiaoyong Tang Jan 1997

Catalytic Control Of Nitric Oxide With Gaseous Or Solid Reducing Materials, Xiaoyong Tang

Theses

Air pollution from mobile sources is an increasingly serious problem throughout most of the industrialized would. Diesel powered vehicles, because of their higher thermal efficiency, tend to emit less carbon monoxide and unburned hydrocarbons than gasoline vehicles, but emit significant quantities of NOx. Therefore, it is essential to develop improved emission control equipment in diesel engines. A fixed bed catalytic reactor was used to study the decomposition of NO and the reduction of NO to N2 by different reductants that can be found in diesel exhaust, such as hydrocarbons, CO and elemental carbon over different catalysts. The …


Relaxation And The Nature Of Electrical Stress Related Defects In Ultra-Thin Dioxide On Silicon, Lihui Xie Jan 1997

Relaxation And The Nature Of Electrical Stress Related Defects In Ultra-Thin Dioxide On Silicon, Lihui Xie

Theses

The instability of defects created in ultra-thin insulator, metal-oxide-silicon devices biased in the direct tunnel regime is investigated. For the case of electron injection from the silicon substrate, nearly complete defect relaxation is observed after the bias is removed, allowing the possibility of re-generating the defects. Modeling the defect generation process and examining differences between initial and subsequent degradation periods lead to an improved picture of both the relaxation process and the nature of the involved defects.


A Student Training Manual For Running The Hysim Computer Simulation Program, Roberta Rosty Jan 1997

A Student Training Manual For Running The Hysim Computer Simulation Program, Roberta Rosty

Theses

Hyprotech's HYSIM computer simulation program is used in the chemical processing industry (CPI) to simulate unit operations, which aid in the design of various different kinds of processing plants. It is important then that chemical engineering students should gain early exposure to a simulation program such as HYSIM, in order to facilitate their comprehension of process engineering design work using this type of program, and to bridge the gap between the textbook knowledge they gain of unit operations in the classroom with some of the actual process engineering work-a-day methods available for solving problems.

The objective of this work was …


Safety Guidelines For Occupational Hazards To The Reproductive System, Laverne Raquel Ogieste Jan 1997

Safety Guidelines For Occupational Hazards To The Reproductive System, Laverne Raquel Ogieste

Theses

Most workers are unaware of the hazards to the reproductive system that surround them in the workplace, and therefore, few if any precautions are taken to avoid unnecessary exposures. In this research, safety guidelines were developed in order to eliminate such dangers from occurring or reoccurring.

These guidelines were developed by reviewing case studies of occupational hazards to the reproductive system, including federal laws and regulations related to safety within the workplace. The following forms were also developed in order to formulate suitable safety guidelines for occupational hazards to the reproductive system. They are: an occupational reproductive survey, a reproductive …


The Effects Of Endothelin On Embryonic Optic Lobe Cultures, Christine Herczku Jan 1997

The Effects Of Endothelin On Embryonic Optic Lobe Cultures, Christine Herczku

Theses

No abstract provided.


Colorimetric Characterization Of Flexographic Process Utilizing Analytical Models, Arturo Aguirre Jan 1997

Colorimetric Characterization Of Flexographic Process Utilizing Analytical Models, Arturo Aguirre

Theses

Not provided.


The Implementation Of A Recycling Program By The Westin Hotel Ottawa Canada, Dean Zervos Jan 1997

The Implementation Of A Recycling Program By The Westin Hotel Ottawa Canada, Dean Zervos

Theses

Not listed.


Verifying The Economic Impact Of Convention Attendees On The Local Economy In The Republic Of China On Taiwan, Pei-Ling Huang Jan 1997

Verifying The Economic Impact Of Convention Attendees On The Local Economy In The Republic Of China On Taiwan, Pei-Ling Huang

Theses

Convention travel has been growing rapidly throughout the world in recent years and becoming a critical component of the hospitality and travel industry. Hosting of conventions, especially international conventions, can be used by host countries as part of a strategic marketing plan to publicize modern development, traditional culture, and tourism resources. It also stimulates economic growth in the hosting country. The purpose of this study is to analyze the differences between the expenditures of delegates staying in hotels and delegates not staying in hotels in each category. It was expected that most of delegates staying in hotels were foreigners and …


Instructions For Educational Videos Used In Undergraduate Classes, Jamie Mcdermott Jan 1997

Instructions For Educational Videos Used In Undergraduate Classes, Jamie Mcdermott

Theses

Includes instructions for preparing gelatin, eggs, whipped cream, pie dough, yeast bread, and quick bread. Also gives information on knives, deep frying and sanitation.