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Theses/Dissertations

1995

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Analysis Of Calibration, Robustness, Detection Of Space-Time Adaptive Rada Using Experimental Data, Murat O. Berin Dec 1995

Analysis Of Calibration, Robustness, Detection Of Space-Time Adaptive Rada Using Experimental Data, Murat O. Berin

Theses

Signal cancellation effects in adaptive array radar are studied under non ideal conditions when there is a mismatch between the true desired signal and the presumed theoretical desired signal. This mismatch results in decreased performance when the estimated correlation matrix has a large desired signal component. The performance of the sample matrix inversion (SMI) method is compared to the eigenanalysis-based eigencanceler method. Both analytical results and the processing on the experimental data from the Mountaintop Program, show that eigenanalysis-based adaptive beamformers have greater robustness to signal cancellation effects than the SMI method. Also, the calibration of the recorded data, and ...


Investigation Of Dynamic Friction In Lubricated Surfaces, Hanuman Rachoor Dec 1995

Investigation Of Dynamic Friction In Lubricated Surfaces, Hanuman Rachoor

Dissertations

The research reported in this dissertation is concerned with the development of friction models for lubricated contacts. A few analytical models have been developed to investigate the friction under dynamic velocity conditions. In this study, two different tribological situations such as conformal and non-conformal contacts have been chosen. Friction modeling covers boundary, mixed and full fluid film friction regions. A new theory based on the elastic properties of the surface materials, and fluid film properties of the lubricant at the contact has been developed to determine the dynamic friction in boundary, mixed and full hydrodynamic lubrication regions. In the full ...


An Investigation Of The Mechanism Of Advanced Oxidation Processes (Aop) Involving Free Radicals And Charged Species., Yaw-Kuen Lin Dec 1995

An Investigation Of The Mechanism Of Advanced Oxidation Processes (Aop) Involving Free Radicals And Charged Species., Yaw-Kuen Lin

Dissertations

Hydrogen peroxide is a key component in Advanced Oxidation Processes (AOP). Its decomposition at different pH conditions has been studied and some interesting results were observed. When the pH value of hydrogen peroxide solution is less than 9, its rate of decomposition is independent of pH. On the other hand, in the pH range of 9-12.6, its rate of decomposition increases as pH increases, and goes through a maximum value then suddenly decreases with respect to pH. A reaction kinetic model with three rate constants in the form of beta probability function was used to describe the experimental data ...


Nondestructive Dynamic Load Testing Of Bridges Using Strain Sensors, Suzanne Boland Dec 1995

Nondestructive Dynamic Load Testing Of Bridges Using Strain Sensors, Suzanne Boland

Theses

This thesis investigates the use of nondestructive bridge load testing utilizing strain sensing equipment. Nondestructive bridge load testing has not been used extensively due to lack of expertise and perceived high cost. It can, however, play a key role when an existing bridge needs to be evaluated. Since most evaluation techniques tend to be conservative, the results from such an evaluation may not represent the real properties of the structural members. The true properties of an existing bridge can be identified using the results from nondestructive static and dynamic load testing. The procedures used to identify a structure with the ...


Implementation Of A Friction Estimation And Compensation Technique, Jayesh N. Amin Dec 1995

Implementation Of A Friction Estimation And Compensation Technique, Jayesh N. Amin

Theses

This thesis reports implementation of a friction estimation and compensation technique on a special laboratory apparatus. In this work, experimental results are reported for the Coulomb friction observer.

The Coulomb friction observer estimates the total friction present in a system, assuming it to be a constant function of velocity. An extension of the observer, utilizing a coupled velocity observer, is used when velocity is not measurable. A modification to the velocity observer is also implemented. Experimental results show a remarkable improvement in the friction estimates which are also compared to the actual friction measurements. The estimates are qualitatively similar to ...


Adaptive Radar In Heterogeneous Environment, Albert Futernik Dec 1995

Adaptive Radar In Heterogeneous Environment, Albert Futernik

Theses

Radar performance in heterogeneous clutter has been a much studied topic. In all the studies so far, various forms of the sample matrix inversion (SMI) technique where used to calculate the weight vector of the processor. In this thesis an eigenanalysis-based technique known as the eigencanceler, is used. Performance of this technique is compared to the performance of the generalized likelihood ration (GLR) processor. This comparison is done using the clutter edge model, in which there is an abrupt change in the clutter power in the reference window. It is shown that the false alarm rate fluctuations, of the cell ...


Design For Quality Manufacturability Analysis Of Total Nonconformity Damaged Parts, Samir R. Gami Dec 1995

Design For Quality Manufacturability Analysis Of Total Nonconformity Damaged Parts, Samir R. Gami

Theses

The competitive nature of modern manufacturing, demands that innovative approaches be applied in order to have a competitive edge. Shortening the product development cycle, the period from initial design to full production, is a priority for most manufacturers today. The DFQM methodology addresses the issue of quality manufacturability (QM) - the likelihood that defects will occur during manufacture of a product in a standard plant. As a consequence, DFQM helps to shorten the design cycle time. The DFQM architecture identifies a variety of design factors and variables that influence specific defects. This process of influencing defects can be described by error ...


Construction Of Accurate Molecular Models Using Laser Stereolithography And Determination Of Nmr Spectra For Amiloride Hydrochloride And Its Free Base, Ana Deborah Ofsievich Dec 1995

Construction Of Accurate Molecular Models Using Laser Stereolithography And Determination Of Nmr Spectra For Amiloride Hydrochloride And Its Free Base, Ana Deborah Ofsievich

Theses

Accurate molecular models were constructed by a rapid prototyping process, called stereolithography. This process uses a computer-controlled laser to cure and solidify a photosensitive liquid polymer. Using a computer-aided design (CAD) program, spheres of appropriate van der Waals or CPK radii were drawn and placed in the three dimensional CAD space, in accordance with the atomic coordinates obtained from quantum mechanical calculations and from neutron diffraction data. These design data were used to drive the stereolithography system where the models were built in the same shape as the CAD image. The models built for the purpose of this work consisted ...


Continuous Monitoring Of Volatile Organic Compound Emissions Using Microtrap Based Injection Technique And Gas Chromatography, Wenjun Chen Dec 1995

Continuous Monitoring Of Volatile Organic Compound Emissions Using Microtrap Based Injection Technique And Gas Chromatography, Wenjun Chen

Theses

A microtrap is made by packing a small diameter tubing with an adsorbent. The microtrap can be rapidly heated with a pulse of electrical current resulting in a sharp desorption that can act as an injection for GC separation. The microtrap can be used in several configurations to concentrate and inject sample in continuous, on-line monitoring system.


Design And Analysis Of Environmentally Safe Cooling Systems For Machine Tools, Haiping Xu Dec 1995

Design And Analysis Of Environmentally Safe Cooling Systems For Machine Tools, Haiping Xu

Theses

Many cooling systems of metal cutting and both their advantages and disadvantages have been reviewed. The cutting forces' relationships, stress distribution, energy consumption and heat generation of orthogonal processes are discussed. A two-dimensional finite element model has been developed to design and analyze a new proposed cooling device, which comes from the idea of "A Novel Cooling Device" proposed by Billatos et al. First, a thermal calculation is completed to compare the temperature difference between two different shapes of coiled pipe. Then, three different cutting conditions, which were considered in the experiments by Childs et al, are conducted under three ...


Remediation And Reuse Of Chromium Contaminated Soils Through Cold Top Ex-Site Vitrification, Wiwat Kamolpornwijit Dec 1995

Remediation And Reuse Of Chromium Contaminated Soils Through Cold Top Ex-Site Vitrification, Wiwat Kamolpornwijit

Theses

More than 150 sites in Hudson County, New Jersey are identified as chromium contaminated sites. Hexavalent chromium, highly soluble in water, is considered as an environmental and health hazard, classified as a group A human carcinogen. In this research, the feasibility was performed to study the possibility of remediation of chromium contaminated soil by ex-situ vitrification and to evaluate reuse potential of vitrified products as highway construction aggregate. A series of physical and chemical analysis was conducted on nine soil samples collected from different chromium contaminated sites. Results were analyzed for their compatibility for vitrification. Sand and carbon were added ...


The Effects Of Chromated Copper-Arsenate (Cca) Pressure-Treated Wood On Local Sediments And Benthos In A Freshwater Lake, William A. Romeo Dec 1995

The Effects Of Chromated Copper-Arsenate (Cca) Pressure-Treated Wood On Local Sediments And Benthos In A Freshwater Lake, William A. Romeo

Theses

This study looked at the sediment and benthic organism effects of exposure to a Chromated Copper-Arsenate (CCA) treated wood bulkhead in a lake environment with respect to 1) the leaching and accumulation of chromium, copper and arsenic in the nearby sediments, 2) accumulation of these metals in local benthic organisms and 3) the effects of these metals on the local benthic community structure. Sediment samples, taken at regular distances away from a CCA bulkhead and three reference areas in a freshwater lake in Wayne, NJ, were sieved to remove the fine particle fraction (<70µm) which was then analyzed for the metals of concern. Benthic organisms were sampled at the same locations, enumerated, identified, dried and also analyzed for the metals in question. Analysis of sediment metal concentrations revealed high levels of copper at all sampling locations. This was attributed to the annual addition and accumulation Of CuS04 added to the lake. There was ...


Comparison Of Adaptive Radar Algorithms : Transformed Smi, Eigencanceler, And Smi, Chaitanya H. Kathiari Dec 1995

Comparison Of Adaptive Radar Algorithms : Transformed Smi, Eigencanceler, And Smi, Chaitanya H. Kathiari

Theses

Advanced airborne radars must perform target detection in the presence of interference and heavy clutter. In many applications, the practical usefulness of adaptive arrays is limited by their convergence rate. In this paper, we first analyze the performance of the SMI method. Then, two other methods, the transformed SMI and the eigencanceler, both based on the principle component inversion (PCI) technique, are described and analyzed by simulation. It is shown by simulation based comparison that the transformed SMI and the Eigencanceler outperform the SMI method. It is also shown that the transformed SMI and the eigencanceler has higher convergence rate ...


Numerical Simulation Of Clipping Distortion In Lightwave Catv Systems, Luay Al-Nadi Dec 1995

Numerical Simulation Of Clipping Distortion In Lightwave Catv Systems, Luay Al-Nadi

Theses

Clipping induced distortion is an essential limit for modulation depth and number of channels in subcarrier multiplexed lightwave video transmission systems. Two different types of laser clipping are compared (single-clipping vs. double-clipping). In this work, the distortion limits imposed by clipping effects, in both directly (single-clipping) and externally (double-clipping) modulated systems, are examined. Numerical simulations were performed to test the efficiency of Saleh's Model. A comparison of results with clipping induced distortion in directly modulated lightwave systems (single-clipping) and clipping induced distortion in externally modulated lightwave systems (double-clipping) is presented, it is shown through numerical simulation that the total ...


Investigation Of Potential Oxygen Defect Mechanism Of Persistent Photoconductivity And Photoinduced Superconductivity In Yba2cu3ox, Denise Catherine Chew Dec 1995

Investigation Of Potential Oxygen Defect Mechanism Of Persistent Photoconductivity And Photoinduced Superconductivity In Yba2cu3ox, Denise Catherine Chew

Theses

In this thesis work, we conclude that oxygen vacancy defects play a fundamental role in the PPC/PISC mechanism and identify the oxygen defects as F centers (an oxygen vacancy which traps two electrons) or F+ centers. Also, the correlation between the peaks observed in the luminescence spectra and those observed in the wavelength dependence of PPC suggest that the photogeneration of charges and their annihilation via luminescent recombination occur in the same level (Cu-O chains) of the YBa2Cu3Ox crystal. Previous models had assigned the peaks in the PPC excitation spectrum to charge transfer in ...


Sensivity Analysis And Design Calculations With Biofiltration Models, Michael Lawrence Cohen Dec 1995

Sensivity Analysis And Design Calculations With Biofiltration Models, Michael Lawrence Cohen

Theses

Biofiltration is a new technology for biological treatment of volatile organic compounds present in airstreams. It is a complex process and thus, engineering models which attempt to describe it are by necessity very involved and contain a large number of parameters.

In this study, two models describing biofiltration of airstreams carrying a single pollutant (VOC) were used in detailed parameter-sensitivity studies. One model concerned biofiltration under steady-state conditions, while the second described the transient behavior of the process. The intent of the sensitivity studies was to determine which model parameters need to be known with accuracy in order to allow ...


Comparison Of Reductive Dehalogenation By Microbial Populations On Adsorptive Versus Non-Adsorptive Bioreactor Support Materials, Linda S. Colella Dec 1995

Comparison Of Reductive Dehalogenation By Microbial Populations On Adsorptive Versus Non-Adsorptive Bioreactor Support Materials, Linda S. Colella

Theses

The overall performance of two bioreactors was studied. The reactor with a wood-based activated carbon as a biosupport completely dehalogenated a higher feed concentration of trichlorophenol than that with Manville beads. The carbon reactor was further characterized by the development of adsorption isotherms for most of the class of chlorophenols. Competitive adsorption wag investigated using an anaerobic medium, and a lignite-based carbon was studied for comparison. The order of adsorption strength on both carbons is trichloropenols> dichlorophenols> monochlorophenols, with the wood-based carbon having higher overall adsorption than the lignite-based carbon. The presence of the anaerobic medium decreased the extent of ...


Implementation Of A Three-Dimensional Non-Intrusive Particle Tracking System, Vivek Gupta Dec 1995

Implementation Of A Three-Dimensional Non-Intrusive Particle Tracking System, Vivek Gupta

Theses

A Three-Dimensional Non-Intrusive Particle Tracking System has been developed at NJIT's Particle Technology Center to provide experimental results for validating theories being developed in the field of Particle Technology. The system utilizes the principle of magnetic induction between several high-frequency miniature transmitters mounted inside a sphere and a set of receiving loop antennae mounted outside the experimental apparatus. Basic theories and algorithms for the tracking system have already been developed. The focus of this thesis is to make the tracking system more accurate, reliable and user-friendly and to apply it to the study of vibrated beds and chute flows ...


Integrating Key Functions In Product Development : A Conceptual Product Development Model For The Korean Context, Jong-Wook Kim Dec 1995

Integrating Key Functions In Product Development : A Conceptual Product Development Model For The Korean Context, Jong-Wook Kim

Theses

The high-tech market is characterized by market uncertainty, technology uncertainty and rapid change. To survive in this risky high-tech market, a company must create competitively effective product development practices that meet its own unique needs and circumstances.

One effective practice is cross-functional integration in the product development process. The advantages of integration include a shortened time to market, successful transformation of research results to production, productivity improvement, innovation project success, and high-quality problem solutions. However, these advantages are rarely obtained in the current product development practices of Korean companies. Their product development efforts are generally characterized by time consuming sequential ...


Gabor Expansion Of An Equivalent Dipole Antenna, Oksana Manzhura Dec 1995

Gabor Expansion Of An Equivalent Dipole Antenna, Oksana Manzhura

Theses

The Gabor representation in the context of an aperture problem is an expansion of a radiated field in terms of a discrete set of linearly shifted and spatially rotated elementary Gaussian beams. The parameters that can be varied in this summation are the number of beams and corresponding beam widths. As the difficulty associated with the unique determination of the expansion coefficients was alleviated, the method has been successfully applied to one and two dimensional apertures. Although, the asymptotic evaluation of expansion functions has reduced the computational burden drasticallym it was at the expense of some loss in accuracy. The ...


Small Computer System Interface (Scsi) Universal Services For The Turbonet Parallel Computer, Artak Ohan Melkonian Dec 1995

Small Computer System Interface (Scsi) Universal Services For The Turbonet Parallel Computer, Artak Ohan Melkonian

Theses

TurboNet is a parallel computer with shared-memory and message-passing hybrid architecture. It employs two boards, with four digital signal processors (DSPs) each, and a host FORCE SPARC CPU-2CE board with a SCSI bus.

Software has been developed in this thesis to provide SCSI services to programs running on the DSPs. DSP programs can therefore fully control assigned SCSI devices at the SCSI command level. Transfer control modifiers ensure compatibility with most SCSI devices.

The software provides service for three SCSI access levels. The "su" SCSI universal device driver is built into the host computer's kernel and is a gateway ...


Characterization Of Low Pressure Chemically Vapor Deposited Boron Nitride Films As Low Dielectric Constant Materials, Manish Narayan Dec 1995

Characterization Of Low Pressure Chemically Vapor Deposited Boron Nitride Films As Low Dielectric Constant Materials, Manish Narayan

Theses

Boron nitride thin films were synthesized on Si and quartz wafers by low pressure chemical vapor deposition using borane triethylamine complex and ammonia as precursors. The films were processed at 400°C, 475°C and 550°C at a constant pressure of 0.5 Torr and at different precursor flow ratios.

The films deposited were uniform, amorphous and the composition of the films varied with deposition temperature and precursor flow ratios. The thickness of the film increased with increasing flow ratio, but, decreased with increasing temperature. The stresses in the film were either mildly tensile or compressive.

The least dielectric ...


Signal Processing Techniques In Heart Rate And Systolic Arterial Blood Pressure Variability Studies, Christopher O'Bara Dec 1995

Signal Processing Techniques In Heart Rate And Systolic Arterial Blood Pressure Variability Studies, Christopher O'Bara

Theses

Power spectral analysis of heart rate and systolic arterial blood pressure variability provides a window to the activity of the autonomic nervous system. To derive power spectra from raw blood pressure and electrocardiogram signals, many steps of signal processing must be performed. Most popular methods of spectral analysis require evenly spaced samples; therefore interpolation and resampling techniques must be used.

The results of the present study indicate that different interpolation techniques result in spectral distortions that vary depending upon the interpolation methods used as well as physiological parameters such as heart and respiration rate. Different interpolation methods applied to heart ...


Design And Development Of Four To Sixteen Channel Video Multiplexers, Ronan Rahimi Dec 1995

Design And Development Of Four To Sixteen Channel Video Multiplexers, Ronan Rahimi

Theses

Video multiplexer series were successfully designed and built for prototype and evaluation both in terms of hardware and software. The hardware platform was designed to accommodate up to sixteen color video input channels for time lapse or real time recording on a single video cassette recorder. This product implements four modes of operation; Live, Record, Playback and Menu mode, which is not a full mode of operation. Menu mode is a series of on-screen programming menus which appears on Live, Record and Playback modes. Menu mode enables the user to program the machine to work under specific modes of application ...


The Development Of An Embedded Wireless Modem Conforming To Advanced Mobile Phone System And Cellular Digital Packet Data Standards, Xin Ren Dec 1995

The Development Of An Embedded Wireless Modem Conforming To Advanced Mobile Phone System And Cellular Digital Packet Data Standards, Xin Ren

Theses

Introduced by AT&T Bell Labs in 1970s, today Advanced Mobile Phone Systems (AMPS) - a first generation analog cellular system serve millions of customers in the United States and 55 other countries, and the number of subscribers is still rapidly increasing. Although digital cellular systems are emerging in recent years, research efforts are still being made to the enhancement of AMPS systems because of their popularity. An example is the new Cellular Digital Packet Data (CDPD) standard announced in 1994. CDPD is an overlay of the existing AMPS, and has the capability of transmitting data packets over such an analog ...


Configuring The Radial Basis Function Neural Network, Insoo Sohn Dec 1995

Configuring The Radial Basis Function Neural Network, Insoo Sohn

Theses

The most important factor in configuring an optimum radial basis function (RBF) network is the training of neural units in the hidden layer. Many algorithms have been proposed, e.g., competitive learning (CL), to train the hidden units. CL suffers from producing "dead-units." The other major factor Which was ignored in the past is the appropriate selection of the number of neural units in the hidden layer. The frequency sensitive competitive learning (FSCL) algorithm was proposed to alleviate the problem of dead-units, but it does not alleviate the latter problem. The rival penalized competitive learning (RPCL) algorithm is an improved ...


Linearly Tapered Slot Antenna, Luis Alberto Tumialan Dec 1995

Linearly Tapered Slot Antenna, Luis Alberto Tumialan

Theses

Design procedure for Linearly Tapered Slot Antennas (LTSA) has been developed and implemented using High Frequency Structure Simulator (HFSS) code based on a finite-element analysis.

A CAD study of two variations of a LISA based on either a stripline or a microstrip feed has been carried out. Circular and radial stubs have been considered in these designs for an antenna operating at 10 Ghz. LTSA on a Duroid substrate fed by a stripline has been designed to operate with better than 12 dB return loss. Fabricated antenna was characterized and had even a wider response than the CAD design. Radiation ...


On The Adaptive Multi-Stage Detector For Cancellation Of Multiuser Interference In Cdma Wireless Communication Systems, Nadir Sezgin Dec 1995

On The Adaptive Multi-Stage Detector For Cancellation Of Multiuser Interference In Cdma Wireless Communication Systems, Nadir Sezgin

Dissertations

The classical multiple access techniques such as Frequency Division Multiple Access (FDMA) and Time Division Multiple Access (TDMA) schemes are band limited in terms of their capacity to be used for mobile radio communication. Recent developments in the area of digital signal processing, makes Code Division Multiple Access (CDMA) as a possible solution to the demand of capacity for the mobile radio communication. The capacity of CDMA is limited by multiuser interference, that is the interference from the other users.

The goal of this dissertation is to improve the multiuser CDMA detector with high Bit Error Rate (BER) performance, low ...


Real Time Control Of Nonlinear Dynamic Systems Using Neuro-Fuzzy Controllers, Amitava Jana Dec 1995

Real Time Control Of Nonlinear Dynamic Systems Using Neuro-Fuzzy Controllers, Amitava Jana

Dissertations

The problem of real time control of a nonlinear dynamic system using intelligent control techniques is considered. The current trend is to incorporate neural networks and fuzzy logic into adaptive control strategies. The focus of this work is to investigate the current neuro-fuzzy approaches from literature and adapt them for a specific application. In order to achieve this objective, an experimental nonlinear dynamic system is considered. The motivation for this comes from the desire to solve practical problems and to create a test-bed which can be used to test various control strategies. The nonlinear dynamic system considered here is an ...


Identifying And Exploiting Concurrency In Object-Based Real-Time Systems, Guohui Yu Dec 1995

Identifying And Exploiting Concurrency In Object-Based Real-Time Systems, Guohui Yu

Dissertations

The use of object-based mechanisms, i.e., abstract data types (ADTs), for constructing software systems can help to decrease development costs, increase understandability and increase maintainability. However, execution efficiency may be sacrificed due to the large number of procedure calls, and due to contention for shared ADTs in concurrent systems. Such inefficiencies are a concern in real-time applications that have stringent timing requirements. To address these issues, the potentially inefficient procedure calls are turned into a source of concurrency via asynchronous procedure calls (ARPCs), and contention for shared ADTS is reduced via ADT cloning. A framework for concurrency analysis in ...