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Full-Text Articles in Engineering

Automatic Analysis Of Electronic Drawings Using Neural Network, Yi Shi Aug 1998

Automatic Analysis Of Electronic Drawings Using Neural Network, Yi Shi

Dissertations

Neural network technique has been found to be a powerful tool in pattern recognition. It captures associations or discovers regularities with a set of patterns, where the types, number of variables or diversity of the data are very great, the relationships between variables are vaguely understood, or the relationships are difficult to describe adequately with conventional approaches.

In this dissertation, which is related to the research and the system design aiming at recognizing the digital gate symbols and characters in electronic drawings, we have proposed: (1) A modified Kohonen neural network with a shift-invariant capability in pattern recognition; (2) An …


Adaptive Bootstrap Signal Separators For Bpsk/Qam-Modulated Wireless Cdma Systems In A Multipath Environment, Nico J.M. Van Waes Aug 1998

Adaptive Bootstrap Signal Separators For Bpsk/Qam-Modulated Wireless Cdma Systems In A Multipath Environment, Nico J.M. Van Waes

Dissertations

CDMA is an attractive multiple-access scheme, because of its potential capacity increase and its anti-multipath fading capability. For satisfactory performance, however, the effect of the "near-far" problem has to be resolved. This problem can be combated by using power-control, which, however, results in an overall reduction in communication ranges, and thus in a loss of capacity. Among other methods for mitigating the near-far problem is the use of decorrelating receivers, both of fixed type, which directly utilizes the cross-correlation of the users codes, and of adaptive type, which uses recursive algorithms that leads to signal decorrelation. Not to lessen the …


Object Oriented 3d Dynamic Simulation Of Flow Of Material Through Hopper, Krishnendu Roy Aug 1998

Object Oriented 3d Dynamic Simulation Of Flow Of Material Through Hopper, Krishnendu Roy

Theses

Development of object oriented 3D dynamic simulation of the particle is considered. This code is based on the soft sphere model dealing with both normal force , tangential force and the friction. The development of such a model and the code is motivated by the need to understand the flow patterns of granular material. The prime effort while developing this code was focused on the data encapsulation and secured access to all the attributes of all physical parameters of the bulk solid, which might be endangered by the random access of the interface of the software. A dynamically bound array …


Analysis Of Multi-Lead Qt Dispersion By Means Of An Algorithm Implemented On Labview, Zafer Sahinoglu Aug 1998

Analysis Of Multi-Lead Qt Dispersion By Means Of An Algorithm Implemented On Labview, Zafer Sahinoglu

Theses

QT dispersion measurement is significant in diagnostic ECG, and several methods are proposed in the literature to implement QT measurement.

This study consists of two parts: The first part was the development of an algorithm to measure both QT interval and QT dispersion. To check the reliability of the algorithm, 25 single channel ECGs were recorded and their QT intervals were computed. On two subjects, three and four lead ECG data were recorded respectively and their QT dispersions were statistically analyzed. Another part of this study dealt with the effect of the electric dipole of the heart on QT dispersion. …


Telephone-Accessed Controller Using Cebus For Device Control Over Power Line, Gerald Aska Aug 1998

Telephone-Accessed Controller Using Cebus For Device Control Over Power Line, Gerald Aska

Theses

The CEBus standard has made it possible for devices developed by different manufacturers to communicate over the power line. Further, the standard allows analog adjustments of devices besides transmitting and receiving binary information. This Controller extends the distance from which these devices can be controlled.

To extend the distance of communication with a device, a telephone line interface was developed that allows the user to communicate with a CEBus device via the Controller. The Controller responses [sic] to Central Office signaling and opens its communication channel to allow the user to provide it with the commands by using the telephone …


Analysis And Applications Of Ftir Systems, Gunjan Navin Doshi Aug 1998

Analysis And Applications Of Ftir Systems, Gunjan Navin Doshi

Theses

Fourier Transform Infrared Spectroscopy (FTIR) is a dynamical instrumental technique used in industry for measuring high quality infrared spectra. Over the last 25 years, the increased demand for having an efficient real-time quantitative measurement technique has led to extensive research and development in the field of FTIR Spectroscopy. Through the use of FTIR, sensitivity has increased, size of the smallest sample that can be analyzed has been reduced, and the number of new applications has exploded. In this thesis, an attempt is made to study the principles, theory, instrumentation and applications of FTIR Spectrometry. We survey the working of spectrometer, …


Improving The Run Time Of The Decomposition Algorithm For Fault Tolerant Clos Interconnection Networks Through Swap Re-Ordering, Andrea Laura Mcmakin Aug 1998

Improving The Run Time Of The Decomposition Algorithm For Fault Tolerant Clos Interconnection Networks Through Swap Re-Ordering, Andrea Laura Mcmakin

Theses

Clos interconnection networks, used in data networks and computing systems, can contain extra switches to be used in faulty conditions. The speed of such fault tolerant Clos interconnection networks is improved through the use these switches in no-fault situations. The network can be represented by a matrix, which is then decomposed using an algorithm, and the switch settings are thus assigned.

The original decomposition algorithm consisted of four element swaps in the following order: wild swap, simple swap, next simple swap, and successive swap. However, by re-arranging these swaps with the simple swap first, followed by the next simple and …


Composite Columns, Magnar Berge Aug 1998

Composite Columns, Magnar Berge

Theses

The purpose of this thesis is to provide an introduction in the design of composite columns. The design methods according to AISC and Eurocode 4 are summarized and provide a procedure to design a composite column. In addition, equation are derived to determine the nominal flexural strength of typical composite cross-sections.


Reuse Of Cold Top Ex-Situ Vitrified Chromium Contaminated Soils In Hot Mix Asphalt Concrete, Gerald Charleston Aug 1998

Reuse Of Cold Top Ex-Situ Vitrified Chromium Contaminated Soils In Hot Mix Asphalt Concrete, Gerald Charleston

Theses

This research investigated the pilot scale feasibility of the remediation of chromium contaminated soil through cold top ex-situ vitrification and the reuse of the vitrified products as highway construction aggregates. There are more than two million tons of chromite ore residues from the chromate extraction manufacturing leftover in Hudson County, New Jersey. They contained both un-leached hexavalent and unoxidized trivalent chromium. Hexavalent chromium is well known as a group A human carcinogen. It is also considered an environmental and health hazard. Of the many ex- situ and in-situ physical, chemical, and biological treatment technologies for chromate production waste, the ability …


Nanofiltration With Organic Solvents And Its Possible Applications To Organic Syntheses, Jose Antonio Whu Aug 1998

Nanofiltration With Organic Solvents And Its Possible Applications To Organic Syntheses, Jose Antonio Whu

Theses

Experimental results on the nanofiltration (NF) separation behavior of three different solvent- compatible membranes are presented for three organic solutes of molecular weights 351, 826 and 1355 in methanol; the manufacturer-specified molecular weight cut-offs (MWCO) of the membranes are 250, 400 and 700. Membranes were primarily tested at 440 psig, at different concentrations of the solutes in methanol; the effect of varying the applied pressure was also briefly explored. The solvent permeation flux and the solute rejection were time dependent for an extended initial period; the membranes had to be compacted to achieve steady-state results. Furthermore, the manufacturer-specified MWCO was …


Synthesis And Characterization Of Silicon Dioxide Films Using Diethyl Silane And Oxygen, Kiran Kumar Aug 1998

Synthesis And Characterization Of Silicon Dioxide Films Using Diethyl Silane And Oxygen, Kiran Kumar

Theses

This study focuses on producing thin and thick silicon dioxide films towards the fabrication of integrated optical sensor capable of monitoring and determining in-situ, the concentration of numerous analyze species simultaneously. In this study, diethylsilane (DES) has been used as a precursor to produce silicon dioxide films by low pressure chemical vapor deposition. The films were synthesized with two different flow ratios of oxygen to DES in the temperature range of 550°C to 800°C at a constant pressure of 200mTorr. The films deposited with lower oxygen to DES flow ratio have very high growth rate but suffer from high tensile …


Tools For The Design Of Flexible Manufacturind Systems, Prashant A. Patel Aug 1998

Tools For The Design Of Flexible Manufacturind Systems, Prashant A. Patel

Theses

Flexibility in manufacturing systems can broaden the horizons for a company. But the means for achieving it are far more critical. This trend is created by the increase in competitiveness, growth of technology along with demand variations, more customization, and short product life cycles. But "Flexible Manufacturing Systems" to most of the manufacturers sounds like a synonym for automation.

A real Flexible Manufacturing System is designed when every unit of the company is synchronized in such a way to respond in a harmony to any changes that come against it. Fine-tuning of each and every part of the company is …


Measurement Of The Baroreceptor Sensitivity Index (Brsi) In The Frequency Domains, Tanvir Raquib Aug 1998

Measurement Of The Baroreceptor Sensitivity Index (Brsi) In The Frequency Domains, Tanvir Raquib

Theses

Time domain analysis for calculating the Baroreceptor Sensitivity Index (BRSI) did not always provide an accurate result. It also had another limitation in that it could not show the influence of the autonomic nervous system for different subjects. The correlation coefficient is a mechanism that was used to either accept or reject the BRSI values in the time domain but the correlation coefficient values changed drastically depending on how many sample points were selected for the calculation.

On the other hand, frequency domain analysis for the BRSI calculation was relatively easier and provided more accurate information compared to the time …


The Determination Of 2-Methylisoborneol And Geosmin In Water Using Fluorescence Spectroscopy, Ramesh Chandra Sharma Aug 1998

The Determination Of 2-Methylisoborneol And Geosmin In Water Using Fluorescence Spectroscopy, Ramesh Chandra Sharma

Theses

Geosmin and 2-Methylisoborneol are responsible for imparting earthy, musty taste and odor qualities to water. The human threshold odor concentrations (TOCs) for 2-MIB and Geosmin vary over a wide range. TOCs of 10ng/1 for Geosmin and 30ng/1 for 2-MIB have been reported.

Currently available methods are time consuming and require use of sophisticated technique and expensive equipment.

Fluorescence spectroscopy has been successfully used in the identification of many organic compounds. Geosmin and 2-MIB have organic origin. This research explores the possibility of using the technique of fluorescence spectroscopy in the determination of Geosmin and 2-MIB. The excitation and emission wavelengths …


Stabilization Of Water Treatment Plant (Wtp) Residuals Using Sorbond, Rituraj Sinha Aug 1998

Stabilization Of Water Treatment Plant (Wtp) Residuals Using Sorbond, Rituraj Sinha

Theses

Disposal of water treatment plant (WTP) residuals has always been an important consideration for the water industry. Stringent water quality standards, environmental regulations, and unavailability of land for ultimate disposal affect disposal of large amounts of this residual. The search for alternate economical disposal options and beneficial use are probably the next most logical and economical step to take.

This study was performed to explore the possibility of stabilization of water treatment plant (WTP) residuals using additives. Three water treatment plant (WTP) residuals from treatment plants in New Jersey were used for the analysis. The objective of this research is …


Utilizing Gis Technology For Brownfields Redevelopment, Jeffrey J. Duteau Aug 1998

Utilizing Gis Technology For Brownfields Redevelopment, Jeffrey J. Duteau

Theses

Typically, when developers, banks and other organizations have an interest in a piece of property they perform an extensive information search to determine if the site is worth purchasing. This search could consist of tax and title information, the location of utilities and major roadways in the area, information on population demographics and environmental contaminant data. An information search of this type could take days, weeks or even months to compile. With a geographic information system (GIS), this search could take a matter of minutes and is displayed in an easy to understand graphic or map form along with a …


Static Compaction Of Test Sequences For Synchronous Sequential Circuits, Lijie Qi Aug 1998

Static Compaction Of Test Sequences For Synchronous Sequential Circuits, Lijie Qi

Dissertations and Theses

Today, VLSI design has progressed to a stage where it needs to incorporate methods of testing circuits. The Automatic Test Pattern Generation (ATPG) is a very attractive method and feasible on almost any combinational and sequential circuit.

Currently available automatic test pattern generators (ATPGs) generate test sets that may be excessively long. Because a cost of testing depends on the test length, compaction techniques have been used to reduce that length. The motivation for studying test compaction is twofold. Firstly, by reducing the test sequence length, the memory requirements during the test application and the test application time are reduced. …


An Information-Theoretical Approach To The Adaptive Segmentation And Classification Of The Sleeping Electroencephalogram, Russell James Clark Aug 1998

An Information-Theoretical Approach To The Adaptive Segmentation And Classification Of The Sleeping Electroencephalogram, Russell James Clark

Wayne State University Dissertations

Sleep is not a single homogeneous state; it consists of several identifiable states. The states are identified by the electroencephalogram (EEG), electrooculogram, and the electromyogram. The most common classification method consists of six classes labeled: wake, stage 1 through 4, and stage REM. A fixed length of data, usually 20 or 30 second epochs, are analyzed and placed in one of the six categories. An all-nigh sleep recording consists of 900 to 1500 such epochs and the task of scoring a record is tedious. Additionally, much of the detail in the EEG is lost due to the size of the …


In-Flight Fatigue Crack Monitoring Of An Aircraft Engine Cowling, Samuel Gordon Vaughn Iii Aug 1998

In-Flight Fatigue Crack Monitoring Of An Aircraft Engine Cowling, Samuel Gordon Vaughn Iii

Master's Theses - Daytona Beach

This research investigates the feasibility of implementing an in-flight fatigue crack monitoring system in an airplane to identify fatigue crack growth. An acoustic emission data acquisition system coupled with a Kohonen self organizing map neural network were used to perform the analysis.

Fatigue cracking was responsible for ripping the top of a fuselage off an Aloha Airlines Boeing 737-200 as it carried passengers over the Pacific Ocean, killing some aboard. This tragedy is perhaps a precursor of problems to come, as our nation’s aircraft age. These planes experience fatigue as they perform their daily routine of ferrying passengers from location …


Architectural Optimization Of Digital Libraries, Aileen O. Biser Aug 1998

Architectural Optimization Of Digital Libraries, Aileen O. Biser

Computer Science Theses & Dissertations

This work investigates performance and scaling issues relevant to large scale distributed digital libraries. Presently, performance and scaling studies focus on specific implementations of production or prototype digital libraries. Although useful information is gained to aid these designers and other researchers with insights to performance and scaling issues, the broader issues relevant to very large scale distributed libraries are not addressed. Specifically, no current studies look at the extreme or worst case possibilities in digital library implementations. A survey of digital library research issues is presented. Scaling and performance issues are mentioned frequently in the digital library literature but are …


Global Positioning System (Gps) Receiver Design For Multipaths Mitigation, El-Sayed Abdel-Salam Gadallah Aug 1998

Global Positioning System (Gps) Receiver Design For Multipaths Mitigation, El-Sayed Abdel-Salam Gadallah

Theses and Dissertations

Multipath effects are a source of error degrading the accuracy of DGPS signal processing. The statistical models of multipath are determined by user location and, in addition are time varying. There is no unified statistical model for the multipath signal. Therefore the solution of the multipath problem using statistical models is difficult. This research introduces a new estimator that can detect the presence of multipath, can determine the unknown number of multipath components and can estimate multipath parameters in the GPS receiver (time delay and attenuation coefficients). Furthermore the multipath signal parameters are estimated at any instant of observation. The …


Development And Realization Of A Single-Mode Optical Fiber Ferrule Mold Insert With Twelve Channels, Hsiharng William Yang Jul 1998

Development And Realization Of A Single-Mode Optical Fiber Ferrule Mold Insert With Twelve Channels, Hsiharng William Yang

Doctoral Dissertations

A manufacturing process for an optical fiber ferrule mold insert with twelve channels has been established. This research project presents mask design, mask fabrication, deep X-ray lithography exposure, resist developing, nickel electroforming, as well as surface finishing to attain the final result. Deep X-ray mask fabrication methods are explored, including mechanically machined masks, micro-EDM masks, and E-beam written masks. The exposures to pattern resists and electroforming to fabricate nickel molds up to 500 $\mu$m thickness are reported in this study. Nickel structures for the optical fiber ferrule insert with twelve channels made by electroforming are the final products. A practical …


Fatigue: Investigation Of A Human Factor For Regional Airline Pilots, Doug Mikkelsen Jul 1998

Fatigue: Investigation Of A Human Factor For Regional Airline Pilots, Doug Mikkelsen

Master's Theses - Daytona Beach

This study analyzed the causes of regional airline pilot fatigue and the impact on pilot performance. An instrument was developed and refined through a field study validation by a panel of experts. The final instrument was distributed to three groups of regional airline pilots. The data supported the literature review, which revealed many causes of pilot fatigue, including flight crew schedules that are not compatible with human limitations; Federal Aviation Regulations (FARs) that have not evolved with the advancement of aircraft performance and the public demand for 24 hour availability of flights; and poor personal habits. An analysis of the …


The Optimized Electrostatic Motor, Christopher Lee Rambin Jul 1998

The Optimized Electrostatic Motor, Christopher Lee Rambin

Doctoral Dissertations

The most common means of electrically activated actuation is the electromagnetic motor. All electromagnetic motors have a low output to weight ratio and low energy efficiency. The motor's weight is due to the coils and magnets used to generate propulsion. The energy loss is mainly the result of Joule heating that is inherent with any current driven device. An electrostatic motor offers the potential of significantly less weight and higher energy efficiency. This lower weight characteristic is due to the epoxide material used to construct the major components of its propulsion unit. Greater efficiency results from the reduced Joule heating …


Fuzzy Logic Applied To System Control To Enhance Commercial Appliance Performance, Glenn Moffett Jul 1998

Fuzzy Logic Applied To System Control To Enhance Commercial Appliance Performance, Glenn Moffett

Doctoral Dissertations

The purpose of this research is to determine the usefulness of fuzzy logic and fuzzy control when applied to a commercial appliance. Fuzzy logic is a structured, model-free estimator that approximates a function through linguistic input/output associations. Fuzzy rule-based systems apply these methods to solve many types of "real-world" problems, especially where a system is difficult to model, is controlled by a human operator or expert, or where ambiguity or vagueness is common.

This dissertation presents fuzzy sets, fuzzy systems, and fuzzy control, with an example conveying the use of fuzzy control of a consumer product and an overview of …


Chemical Kinetics And Heat Transfer In Polyurethane Foam And Resin Composites, Yumi Morisaki Jul 1998

Chemical Kinetics And Heat Transfer In Polyurethane Foam And Resin Composites, Yumi Morisaki

Master's Theses - Daytona Beach

A development of the composite materials parts require knowledge of the theoretical model that describes the physics, the chemical kinetics, and the heat-transfer properties of the materials.

For this work, the chemical kinetics of the polyurethane foam and the fiberglass-reinforced resin is investigated individually. An adiabatic method, which is commonly used by many investigators, is used for the polyurethane foam, while an isothermal degree and the rate of cure relationship is applied for the resin. A heat transfer effect during the curing process of both polyurethane foam and the resin is also investigated. A common approximate method for the heat-conduction …


The Solution Of Hypersingular Integral Equations With Applications In Acoustics And Fracture Mechanics, Richard S. St. John Jul 1998

The Solution Of Hypersingular Integral Equations With Applications In Acoustics And Fracture Mechanics, Richard S. St. John

Mathematics & Statistics Theses & Dissertations

The numerical solution of two classes of hypersingular integral equations is addressed. Both classes are integral equations of the first kind, and are hypersingular due to a kernel containing a Hadamard singularity. The convergence of a Galerkin method and a collocation method is discussed and computationally efficient algorithms are developed for each class of hypersingular integral equation.

Interest in these classes of hypersingular integral equations is due to their occurrence in many physical applications. In particular, investigations into the scattering of acoustic waves by moving objects and the study of dynamic Griffith crack problems has necessitated a computationally efficient technique …


Multiple Streams Synchronization In Collaborative Multimedia Systems, Emilia Stoica Jul 1998

Multiple Streams Synchronization In Collaborative Multimedia Systems, Emilia Stoica

Computer Science Theses & Dissertations

With the recent increase of the communication bandwidth and processor power, new types of applications have emerged. Among them, there are multimedia application, in which users are able to control, combine, and manipulate different types of media, such as text, sound, video, computer graphics, and animation. A key requirement in any multimedia application is to synchronize the delivery of various media streams to the user. To achieve this, the sender has to provide the temporal relations between the streams as they are captured. Since the receiver uses this information in streams presentation, its accuracy is very important.

Our main contribution …


Consortia As Technology Innovation Management Vehicles: Toward A Framework For Success In Venture Based Public-Private Partnerships, Ralph B. Saunders Ii Jul 1998

Consortia As Technology Innovation Management Vehicles: Toward A Framework For Success In Venture Based Public-Private Partnerships, Ralph B. Saunders Ii

Engineering Management & Systems Engineering Theses & Dissertations

The purpose of this research was to explore the approach by federal/state agencies, university, and private sector consortia to develop and manage commercialization of innovation technologies. The evaluation, support, and management of technologically based consortia has traditionally been held in the private sector. There is a somewhat mature literature guiding innovation management (Utterback 1996; Rosenberg et al. 1994; Quinn 1997, 1992) in the private sector. However, there is an increasing emergence of consortia consisting of universities, industrial/private sector entities, and government agencies joining in collaborative efforts to launch technology based initiatives. These consortia are non-traditional and the applicability of traditional …


Electrical Characteristics And Parallel Operation Of Microhollow Cathode Discharges, Wenhui Shi Jul 1998

Electrical Characteristics And Parallel Operation Of Microhollow Cathode Discharges, Wenhui Shi

Electrical & Computer Engineering Theses & Dissertations

This thesis describes the electrical properties of microhollow cathode discharges with argon as filling gas. The appearance and current-voltage characteristics of microhollow cathode discharges have been recorded. Three kinds of discharge modes (predischarge, hollow cathode discharge and abnormal discharge) have been observed. The range of operation of the hollow cathode discharge has been found to be 0.5 < pD & 5 Torr cm in argon. By reducing the hole diameter to 100 pm, we were able to operate the discharge to atmospheric pressure in a dc mode. The possibility of dc parallel operation of microhollow cathode discharges was explored. Parallel operation could be obtained without individual ballast for discharges with a positive I-V slope greater than 10 V/mA over a voltage range of more than 5 % of the sustaining voltage. For parallel operation outside the range the ballasting is required. This model was explored by using a segmented anode model. The result of the simple calculation coincides well with the experiment result, where a semi-insulator silicon was used as distributed ballast.