Engineering Commons^™

Synthesis Of Silicon Oxide/Vycor Composite Membrane Structures By An Optimized Lpcvd Process, Abhijit Datta

Theses

This study is focused on development of highly selective ceramic membrane structures consisting of silicon dioxide films synthesized by low pressure chemical vapor deposition (LPCVD) on mesoporous Vycor substrates. The ability of easily altering the composition of such films by varying the LPCVD processing parameters affords the opportunity of microengineering the pore structure by reducing the diameters of pre-existing pores in the support. The process parameters investigated include, deposition temperature, total pressure, and flow rate of oxygen. Both the kinetics and select properties of the deposits were examined. The growth rate as a function of temperature was seen to follow …

Development Of An Expert System To Facilitate A Pump Manufacturing/Warehouse Facility, Muhammad Mutahir Ghauri

Theses

The objective of this study is to evaluate the effectiveness of utilizing an expert system technology as it relates to manufacturing. It appears that our industries are still uncertain about this technology. In the first phase of this study, procedure for deployment of this technology is discussed. Secondly a knowledge-based expert system is developed, using a VP-Expert microcomputer shell. The system is made of three modules, inventory module, cost analysis module, and decision making module (for the selection of pumps).

A warehouse was selected for the analysis, which carries the finished product in the form of pumps. The quantities and …

The Mobile Satellite Service (Mss) Systems For Global Personal Communications, Kiho Lee

Theses

A worldwide interest has arisen on personal communications via satellite systems. The recently proposed mobile satellite service(MSS) systems are categorized four areas: geostationary earth orbit(GEO) systems, medium earth orbit(MEO) systems, low earth orbit(LEO) systems, and highly elliptical orbit(HEO) systems. Most of the systems in each category are introduced and explained including some technical details. The communication links and orbital constellations of some systems are analyzed and compared with different categories, and with different systems. Some economical aspects of the systems are mentioned. The regulatory issues about frequency spectrum allocation, and the current technical trends in these systems are summarized.

Mechanical Behavior Of Polystyrene Foam Bead Lightweight Concrete, Hai-Ying Ni

Theses

This thesis is designed to investigate the effect of porosity on the mechanical properties (strength and modulus) of concrete, and to evaluate the effect of silica fume on the mechanical properties of the polystyrene foam bead lightweight concrete. In this research we made the lightweight concrete by using polystyrene foam beads as light weight aggregate and studied its mechanical properties in detail. Due to the near zero density and modulus of foam beads, we were able to consider it as "porosity". We could then control porosity in concrete by varying foam bead volume fraction.

In our experiments we used the …

Volatilization Of Volatile Organic Compounds From Complex Wastewaters, Syed Sikandar Qadry

Theses

A variety of volatile organic solvents used in the pharmaceutical and specialty chemical industries end up in wastewater collection and treatment systems. EPA has classified these VOCs into groups depending on their potential to volatilize from the wastewaters. In making this classification, Henry's Law, which is valid at very low concentrations, has been used to describe the vapor-liquid equilibrium. But, in reality the concentrations observed in the wastewaters are often too high for Henry's Law to be valid and it is inappropriate to assume that equilibrium has been achieved for every compound.

This project evaluates the volatilization rates, both experimental …

Area And Perimeter Measurements Of Cells With Bound Fluorescent Antibodies, Aicha Weiss

Theses

The objective of this research was to geometrically analyze the characteristics of cells, specifically area and perimeter. The images were transferred from HP A900 system to an AVS work station. The images were visualized and manipulated by the AVS which permits the distinction between the cell body, fluorescent object, and background. The intrinsic geometry of the cell was determined by using image processing algorithms written in C. The images were then passed through a threshold filter, thereby yielding a black background and a white cell body. The perimeter calculation was then applied to the black and white images. Two test …

The Photolithographic Patterning Of Porous Silicon Using Silicon Nitride And Silicon Carbide Films As Masks, Hong Wang

Theses

In this study, a simple photolithographic pattern process for porous silicon is described. The process utilizes silicon nitride or silicon carbide coated on the top of silicon wafer as a masks. Then a test pattern was projected on the sample by illumination during anodic etching in HF:ethanol solution which produced microcracks in regions illuminated during anodization. Creation of these microcracks resulted in formation of porous silicon in the underlying regions. The cracking is related to the stress in the thin film. The films with tensile stress exhibit cracking while compressive stress samples do not. Compared to silicon carbide films, silicon …

Am/Fm Digital Audio Broadcasting In-Band On-Channel Transmission, Michael Meyer

Theses

This thesis examines the in-band on-channel transmission of digital audio data for application in Digital Audio Broadcasting (DAB). The premise is to use the existing FM channels for transmission of DAB. For the FM channel used for analog audio transmission, two different scenarios are suggested and investigated.

In the first scenario, to enable overlay of the new DAB and current FM transmissions, the digital data is modulated by a direct sequence spread spectrum signal to bring the average transmitted power below that of the FM signal using the same channel. The FM signal interferes with the digital transmission and it …

Statistical And Finite Element Analysis Of The Effects Of Random Input Parameters On The Mechanical Characteristics Of Sheetmetal Forming Processes Using Quadrature Method, Yu Quan

Theses

In this thesis, the computer aided finite element analysis is implemented in the analysis of sheetmetal forming process. To rationalize the experimentation and analysis, the statistical method is introduced to study the variability of sheetmetal deformation process and final shape with respect to the variation of different parameters.

In Chapter 2, the basic characteristics and considerations of deep drawing operation is described with emphasis on the study of geometrical and physical variables of the forming process.

Chapter 3 discussed the three phases which are encountered in the computer aided finite element analysis. As a typical representative of professional finite element …

Laborconsult : An Expert System For Evaluating Fetal Heart Rate And The Progress Of Labor, Wendy Raymond-Fink

Theses

LaborConsult is a rule-based expert system designed to aid the non-expert practitioner in monitoring the progress and fetal tolerance of labor. The expert system obtains from the user the values of the following labor variables: cervical dilatation, fetal station, and the time between and duration of uterine contractions. The rates of cervical dilatation and fetal descent are then calculated and compared to labor standards. Additionally, the consultation assists the user in the analysis of electronic fetal monitor tracings.

The expert system development tool VP-Expert allows the interfacing of the consultation with the spreadsheet Lotus 1-2-3. This enables the creation of …

Design For Quality Manufacturability Analysis Of Missing/Misplaced Parts And Part Interference, Altaf Yusuf Tamboo

Theses

Design for Quality Manufacturability (DFQM) is an approach that addresses the issue of quality manufacturability (QM) - the likelihood that defects will occur during manufacture of a product in a standard plant. The DFQM methodology is based on the premise that defects found in assembled products are often influenced by some features of the design and/or assembly process (influencing factors). These influencing factors cause defects in the presence of certain error catalysts.

One of the influencing factors is geometrical features such as shape and symmetry. A classification scheme for part shape and symmetry is developed. This scheme is summarized in …

Design Of A Lapd Interface Using The T7130 Multichannel Lapd Controller And The T715a Synchronous Protocol Data Formatter, Hopeton Saint John Walker

Theses

As the ISDN telecommunications standard gains acceptance, there is an ever increasing need for intelligent interfaces to implement the L2 protocol known as LAPD. The T7130 MLC, the T7115A SPYDER-T and the MC68020 microprocessor were used to design a LAPD Interface that conforms to the LAPD protocol as specified by CCITT.

The LAPD Interface utilizes a Shared Memory Array which is attached to the Data Link Processors in a single bus configuration. The SMA Arbitration Control allows access to the SMA on a prioritized basis and was implemented as a state machine using PAL's. L2 drivers and L3 management software …

Wear And Friction Of Hylamer And Polyethylene Against Cobalt Chromium A Pin-On-Disc Study, Jerry D'Alessio, Ii

Theses

Understanding friction and wear of biomaterials is essential to the success of any prosthetic joint. A pin-on-disc wear tester is used to find the friction and wear of pins of one material on a coupon of medical grade cobalt chrome. In this experiment six pins of UHMWPe (ultra high molecular weight polyethylene) and six pins of Hylamer® from Du Pont Manufacturing were tested. Four separate runs were made. The tests were performed for ten million cycles, stopping every one to one and a half million cycles for data acquisition. Volumetric wear, wear rate, and coefficients of friction were measured. Both …

Development Of A Multi-Lead Trans-Thoracic Impedance Pneumograph For Heart Rate Variability Studies, Curtis Bashford

Theses

In this study, a device that measures respiratory tidal volume and ECG for use in heart rate variability studies, was designed, built and tested. The device developed is a Multi-Lead Trans-Thoracic Impedance Pneumograph, which determines tidal volume on a breath by breath basis, utilizing both hardware and software. It uses standard ECG electrodes which provide increased comfort and inability to the subject over traditional spirometry methods. The device operates similar to traditional bipolar impedance pneumographs except that instead of only one lead (electrode pair), four leads are acquired simultaneously using time-division multiplexing; providing data from different locations and vectors on …

Wear Of Polyethylene And Hylamer On Cobalt-Chromium : A Knee Simulator Study, Alessandro F. Canonaco

Theses

Two tests were conducted to examine the wear characteristics of tibial bearings used in total knee replacement systems. Each test consisted of six A/P Glide Tibial Bearings each having a conical control arm. The plastic portion of the conical bearings were all made of UHMWPe. Each of these bearing systems was mounted onto a Co-Cr alloy tibial platform and Co-Cr alloy LCS (low contact stress) femoral component . These test samples were mounted onto the New Jersey Mark III Knee Simulator System. The simulator was configured to produce flexion and axial rotation to simulates normal gait. Each test ran at …

Investigation Of Velocity Distribution Within High Speed Waterjet, Hong Cao

Theses

The aim of this research was to investigate velocity distribution within the water jet at different conditions of jet formation. The water jet (WJ) velocity was measured by the use of Laser Transit Anemometer (LTA) and statistical technique which improved the accuracy of the velocity determination.

The velocities were measured for different diameters of the sapphire nozzle under different water pressures at different axial stand off distances and radial distances across the jet. The experiments performed in this study enabled us to evaluate the effects and conditions of the water jet on the velocity distribution. The acquired results provide information …

Performance Evaluation And Sequence Control Of An Automatedmanufacturing System, Vijaykumar D. Desai

Theses

In an automated sequential manufacturing system Programmable Logic Controllers (PLC) are widely used. As the control specification varies, the control software needs to be rewritten to accommodate the new specification. Since PLC has high flexibility, one can update the current system while it is running thereby making easier implementation. In order to design flexible, reusable and maintainable control software, a good modeling tool is required. Petri nets are such a tool. Which facilitates analysis of behavioral properties, performance evaluation, and systematic construction of discrete event simulators and controllers. In this thesis a system with one robot and five sequential work …

Case Study Of Assembly Defects In Manufactured Products, Michael J. Withka

Theses

Design for Quality Manufacturability (DFQM) is a design tool that empowers engineers to create designs that are easily and effectively transformed into manufactured products. The goal of this methodology is to make designers aware of design characteristics that may lead to product defects during the assembly process. Acknowledging the possibility of these defects will enable the designer to institute design modifications early in the design phase. The benefits realized in this approach are a reduction in the number of defects in the finished product, reduced product cycle times, a reduction in monitoring costs and a reduction in time-to-market.

This thesis …

Design For Quality Manufacturability Analysis For Common Assembly Process, Suriyanarayanan Ramachandra

Theses

The globalization of market economy has precipitated a dramatic increase in competition necessitating the need for higher quality products at lower cost in shorter time periods. Shorter life cycles and proliferation of products has made companies integrate all the phases of manufacturing to bring about a superior design. Design for Quality Manufacturability (DFQM) provides a technique to invoke manufacturing and assembly considerations while designing a product. The DFQM architecture identifies factors consisting of several variables that are influenced by certain error catalysts to cause one or more specific defects. A methodology is suggested to identify and quantify these error catalysts …

An Adaptive Asynchronous Cdma Receiver And Its Convergence Analysis, Lizhi Zhong

Theses

An adaptive CDMA receiver scheme assuming perfect synchronization has been generalized in this thesis to the asynchronous channel, a much more practical assumption of the real system. Similar formulas are derived and as its synchronous version, it is still near-far resistant and requires no knowldge [sic] of received signal amplitudes and training sequences. Thus, sophisticated high-precision power control and user power estimation are not necessary and the receiver is particularly useful in mobile communications since it can adjust itself adaptively to changes in the power of the users. Tile convergence and transient behavior of the receiver are also investigated and …

Heart Rate Variability Studies On Ambulatory Subjects Using Ekg Derived Respiration, Xiaorui Tang

Theses

Power spectral analysis of heart rate variability (HRV) provides a powerful non-invasive too] for exploring the balance between sympathetic and parasympathetic components of the autonomic nervous system. In the spectrum of HRV, there are three distinct peaks. The high frequency (HF) band (0.15 to 0.4 Hz) is correlated with parasympathetic activity and this is the band of interest 'in the study.

Two OTOUPS Of SL113jeCtS were considered in this work, stroke survivors and subjects performing an oral presentation in front of an audience. Data were collected with a Holter monitor to allow for ambulatory recording. Respiration was derived from the …

Simulation Study Of Particle Tracking System, Prashant B. Patel

Theses

A particle tracking system is being developed in the Particle Technology Laboratory of the Mechanical Engineering Department, at NJIT, In this thesis, an attempt is made to understand the effect of various parameters on the errors in the computed position and orientation of the sphere being tracked. Simulation results for a single transmitter assembly as well as a three transmitter assembly with 6, 9 and 17 antennae are presented. The effects of the level of noise in the voltages on the solution for the single transmitter assembly and three transmitter assembly are discussed. The concept of virtual antenna is introduced …

Single-Axis Agonistic Motion Control System With Electro-Magnetic Actuators, Alexander Rokhvarg

Theses

A novel single-axis motion control system using solenoid electromagnet actuators is built and successfully controlled using a non-linear real-time control algorithm. Procedures for defining and modeling the electromagnetic actuator are established and implemented. Discrete-time nonlinear control law with global asymptotic stability and zero steady-state error is designed and numerically optimized. Stable operation with small-signal 0dB crossover frequency of 370 Rad/sec and positioning RMS steady-state error of better than 4 micron is achieved. Time domain parameters are verified on a working prototype. A step reference response positioning a 0.35 Kg mass payload over 1 cm travel in under 30 milliseconds is …

Viscoelastic Effects On Parallel Flow Stability, Transition To Turbulence, And Turbulent Flow, Michael Garofalo

Theses

The classical two dimensional theory of stability of parallel flow is extended to viscoelastic fluids. How the elasticity of the fluid affects the point of stability and determines the point of transition to turbulence is analyzed. In addition the magnification of disturbances is elucidated. This study is based on a viscoelastic constitutive equation which has been successful in predicting the experimental trends of various unsteady high shear rate laminar flows. A viscoelastic stability equation which is an extension to the Orr-Sommerfeld equation for a Newtonian fluid is derived and solved for a flow between parallel plates superimposed by a two-dimensional …

Measurement Of The Reaction To Stress And Meditation Using Brain Wave Coherence And Heart Rate Variability, Christopher B. King

Theses

Measurement of physiological parameters associated with the stress response and the relaxation response caused by various forms of meditation can provide valuable information about the reaction of the body to the mind and to the external environment.

This study used two different techniques to evaluate physiological parameters. The first part examined the meditation response by recording the EEG and calculating the coherence between brain waves originating from different parts of the brain. It was found that high levels of coherence in the alpha portion of the EEG frequency band coincided with a restful state associated with the relaxation response. In …

A Pharmacokinetic Model Of The Liver, Samirbhai Rameshbhai Patel

Theses

The liver is the major organ where chemical breakdown of organic and inorganic compounds takes place. A pharmacokinetic heterogeneous model was developed for the local anesthetic and antiarrhythmic drug lidocaine. It was assumed that transport and elimination of lidocaine and its metabolites are linear with concentration. Simulations were done using VisSim software on a 486 based personal computer to obtain concentration profiles for hepatic clearance and for step input of the drug and its metabolites. It was found that the rate of uptake and rate of breakdown were 0.48 min^-1 and 0.49 min^-1 respectively for lidocaine. The results …

Preoperative Risk Assessment For Cardiac Surgery Using Piecewise Linear Regression Model, Arifa Zafar

Theses

In the present climate of quality assurance policies, rigorous requirements for informed consent, and a constantly changing patient population, a system of preoperative risk assignment for cardiovascular surgery was developed to monitor and evaluate surgical outcomes. The goal of this work is to estimate the preoperative risk associated with cardiac bypass surgery for patients in different risk categories. These risk categories are determined by the Parsonnet model which is based upon studying the severity of illness. The Parsonnet model assigns a risk value to a range of risk factors consisting of patient attributes and disease parameters. The aggregate of these …

Low Pressure Chemical Vapor Deposition Of Silicon Nitride Films From Tridimethylaminosilane, Xin Lin

Theses

In this study amorphous stoichiometric silicon nitride films were synthesized by low pressure chemical vapor deposition (LPCVD) using tri(dimethylamino) silane (TDMAS) and ammonia (NH₃). The growth kinetics were determined as a function of temperature in the range of 650 - 900 °C, total pressure in the range of 0.15 - 0.60 Torr, and NH₃/TDMAS flow ratio in the range of 0 - 10. At constant condition of pressure (0.5 Torr), TDMSA flow rate (10 sccm) and NH₃ flow rate (100 sccm), the deposition rate of as-deposited silicon nitride films was found to follow an Arrehnius …

Simulation Of Activity Rhythms In The Hamster, Paul Qassis

Theses

In this research, an effort was made to better understand light-dark cycles which influence the physiological and psychological rhythms, circadian rhythms and their behavior. The research concentrated on mathematically modeling circadian rhythms (specifically hamsters' circadian activity rhythms) and establishing a physical correlation and creating a meaningful relationship between the mathematical model's parameters and the real biological oscillators which are responsible for these rhythms. The internal nature of the circadian rhythms is unclear. There is insufficient information and empirical data that describe them. Indirect means have to be employed for the description and exploration of such rhythms. Extensive real data analysis …

A Systematic Approach To Defense Diversification, Sathappan Venkatachalam

Theses

The decline in defense spending has resulted in defense dependent companies seeking new markets through re-designing existing products, developing new products and restructuring their businesses. Defense diversification is defined as the process of transitioning a defense company's core capabilities (technologies, products, services) into commercial and non-Department of Defense government markets. A combination of site visits and review of the literature on defense diversification demonstrates the need for diversifying companies to adopt a systematic approach.

A concurrent new product development/product redevelopment model is proposed, based on the principles of concurrent engineering. The model consists of an eight phase development cycle and …