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1995

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Full-Text Articles in Engineering

Zastosowanie Modelowania Matematycznego Do Oceny Zanieczyszczenia Powietrza Powodowanego Przez Motoryzację, Marian Mazur, Robert Oleniacz, Bożena Biernat-Oleniacz Dec 1995

Zastosowanie Modelowania Matematycznego Do Oceny Zanieczyszczenia Powietrza Powodowanego Przez Motoryzację, Marian Mazur, Robert Oleniacz, Bożena Biernat-Oleniacz

Robert Oleniacz

The paper presents the results of an inventory of sources of air emissions from the city of Nowy Sacz (Poland) with regard to pollutant emissions from road transport, industrial processes, combustion plants and low-emissions from household furnaces. Particular attention has been devoted to assessing the impact of traffic on air quality in the city. Specified share of emissions from motor vehicles in the state of air pollution in the city center and its outskirts using the method of the atmospheric dispersion modeling.

English title: The use of mathematical modeling to assess air pollution caused by road transport.


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 ...


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 ...


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 ...


On The Optimization Problems In Multiaccess Communication Systems, Gangsheng Wang Dec 1995

On The Optimization Problems In Multiaccess Communication Systems, Gangsheng Wang

Dissertations

In a. communication system, the bandwidth is often a primary resource. In order to support concurrent access by numerous users in a network, this finite and expensive resource must be shared among many independent contending users. Multi-access protocols control this access of the resource among users to achieve its efficient utilization, satisfy connectivity requirements and resolve any conflict among the contending users. Many optimization problems arise in designing a multi-access protocol. Among these, there is a class of optimization problems known as NP-complete, and no polynomial algorithm can possibly solve them. Conventional methods may not be efficient arid often produce ...


On Optimal Design And Applications Of Linear Transforms, Mehmet V. Tazebay Dec 1995

On Optimal Design And Applications Of Linear Transforms, Mehmet V. Tazebay

Dissertations

Linear transforms are encountered in many fields of applied science and engineering. In the past, conventional block transforms provided acceptable answers to different practical problems. But now, under increasing competitive pressures, with the growing reservoir of theory and a corresponding development of computing facilities, a real demand has been created for methods that systematically improve performance. As a result the past two decades have seen the explosive growth of a class of linear transform theory known as multiresolution signal decomposition. The goal of this work is to design and apply these advanced signal processing techniques to several different problems.

The ...


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 ...


Anaerobic Digestion And Acid Hydrolysis Of Nitrocellulose, Fong-Jung Tai Dec 1995

Anaerobic Digestion And Acid Hydrolysis Of Nitrocellulose, Fong-Jung Tai

Dissertations

In this investigation, studies were conducted to evaluate the biodegradation of nitrocellulose in anaerobic batch reactors with and without the supplemental carbon inducers, such as cellulose, cellobiose, and lactose. Results from the anaerobic study show that degradation of nitrocellulose alone is difficult and that nitrocellulose degradative enzymes could be induced by the three inducers tested. As high as 48.91% conversion could be obtained at Cellulose/Nitrocellulose ratio of 1 to I. Studies also indicated that type 20 and 50 celluloses would be more effective and optimum pH was about 6.4 in biodegradation of nitrocellulose. Three testing systems, namely ...


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 ...


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 ...


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 ...


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 ...


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 ...


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 ...


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 ...


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 ...


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 ...


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 ...


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 ...


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 ...


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 ...


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 ...


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 ...


Adaptive Space-Time Processing For Wireless Communications, Xiao Cheng Bernstein Dec 1995

Adaptive Space-Time Processing For Wireless Communications, Xiao Cheng Bernstein

Dissertations

Adaptive space-time processing techniques have been found to increase the capacity of two major, multiple-access wireless communication systems: Time Division Multiple Access (TDMA) and Code Division Multiple Access (CDMA).

In an IS-54 TDMA system, the frequency re-use factor has to be set to 7 so that cells with the same spectrum are separated far enough to meet a required carrier-to-interference ratio (CIR). Space processing uses multiple antennas which, in turn, provide alternative signal paths in order to cancel interferences and combat multipath fading. We have proposed the eigencanceler method and have reviewed the theoretical optimum combining and the feasible direct ...


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 ...


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 ...


A Comparative Study Of Image Compress Schemes, Kui Wang Dec 1995

A Comparative Study Of Image Compress Schemes, Kui Wang

Theses

Image compression is an important and active area of signal processing. All popular image compression techniques consist of three stages: Image transformation, quantization (lossy compression only), and lossless coding (of quantized transform coefficients).

This thesis deals with a comparative study of several lossy image compression techniques. First, it reviews the well-known techniques of each stage. Starting with the first stage, the techniques of orthogonal block transformation and subband transform are described in detail. Then the quantization stage is described, followed by a brief review of the techniques for the third stage, lossless coding.

Then these different image compression techniques are ...


Determination Of Physical Parameters Affecting Biofiltration Of Vocs, Steven Matthew Wojdyla Dec 1995

Determination Of Physical Parameters Affecting Biofiltration Of Vocs, Steven Matthew Wojdyla

Theses

This study dealt with the determination of physical and design parameters affecting the transient behavior of classical biofilters employed in removal of VOCs from airstreams. The column packing material consisted of a mixture of peat and perlite particles (2:3, v:v). The design parameters investigated were the density of the packing material, its porosity, and the void fraction of the filter-bed. The physical parameters investigated were the characteristics of adsorption equilibrium between VOCs and packing material, and the mass transfer coefficients of VOCs to the packing material.

The density of the packing material was found to be 0.679 ...