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Detection And Robustness Of Digital Image Watermarking Signals : A Communication Theory Approach, George F. Elmasry Aug 1999

Detection And Robustness Of Digital Image Watermarking Signals : A Communication Theory Approach, George F. Elmasry

Dissertations

The detection and robustness of the watermark signal is studied from a communications point of view. The contributions of this dissertation are presented in two parts. The first part, which covers the detection aspect, introduces a new digital image watermarking approach that embeds meaningful information in a copyright protection watermark signal; demonstrates the need to approach the watermark signal as a power-constrained signal; studies the relationship between the watermark signal dimension and the image capacity to the signal; explains the similarities and differences between detecting the watermark signal and detecting a signal over a spread-spectrum communication channel; and analyzes the …


Computer Automated Experimentation For The Control And Assessment Of The Classically Conditioned Eyeblink Response, Michael Terrence Bergen Aug 1999

Computer Automated Experimentation For The Control And Assessment Of The Classically Conditioned Eyeblink Response, Michael Terrence Bergen

Theses

The use of the classically conditioned eyeblink response, a form of associative learning, is a growing method of experimentation in modem science. This type of associative learning, has many features that make it useful for applications in the study of specific neurological functions. The goal of this project was to design and implement a software system for the automated control and on-line evaluation of a classical conditioning experiment for use with human subjects. A program was developed in the LabVIEW programming environment by National Instruments. Basic hardware components produce acoustic signals, deliver airpuffs, and sense and condition physiological responses. Safety …


Analysis Of Long-Term Heart Rate Variability Using Labview, Daniel Yang Aug 1999

Analysis Of Long-Term Heart Rate Variability Using Labview, Daniel Yang

Theses

Long-term heart rate variability measurement is important in understanding the activities of the autonomic nervous system. Many methods and implications of long-terrn HRV were available in the literature. The first two studies focused on two data analysis techniques that were used on a normal subject. The first study focused on the 1/f fluctuations. For this analysis, three 1 1h heart rate variability data sets were collected with the Polar Vantage NV. A LabVIEW program was used to calculate the power spectrum of the heart rate, and then the 1/f line was calculated by taking the log of the power spectrum …


Interventions Of Water Jet Technology On Skin Surgery, Kittipat Vichyavichien Aug 1999

Interventions Of Water Jet Technology On Skin Surgery, Kittipat Vichyavichien

Theses

The perfect and precise surgical cut, similar to today's laser one, is very important in many surgeries, especially in dissection and to recanaize arterial occlusive lessions. Causing no coagulation is one of the advantages of water jet because it generates no heat. It also provides omni-directional cutting capabilities at very high speeds, resulting edge quality that is usually superior to other existing conventional cutting processes. Debris is always carried away from incisions by jet stream and less damaged tissue, than mechanical incisions. In addition, water jet exerts minimal contact pressure on the tissue being cut due to the small diameter …


Characterization Of Steel Corrosion In An Aggressive Environment, Sung Min Maeng Aug 1999

Characterization Of Steel Corrosion In An Aggressive Environment, Sung Min Maeng

Theses

As part of the Sustainable Green Manufacturing Program, the corrosion resistance of sputtered tantalum is being studied in order to evaluate it as a replacement coating for electroplated chrome. To accomplish this, studies were conducted to evaluate corrosion properties of the gun barrel steel by employing corrosion rate and bulk measurements including x-ray diffraction (XRD), scanning electron microscopy (SEM)/energy dispersive x-ray spectroscopy (EDX), and x-ray fluorescence (XRF), as well as synchrotron-based x-ray absorption spectroscopy (XAS).

Corrosion behavior of steel immersed in an aggressive environment of 37.8 % hydrochloric acid at room temperature was investigated as a function of time from …


Measurements Of The Effects Of Colored Light On The Body, Lynne Hendrickson Aug 1999

Measurements Of The Effects Of Colored Light On The Body, Lynne Hendrickson

Theses

Colored light is used in movies, restaurants, and other situations to create particular environments. It creates a mood and sets a stage for specific events.

This study used colored light to create relaxation and stress in order to evaluate physiological reactions in the human body. In all four studies of this paper, EEG, EKG, and peripheral blood flow were recorded and observed and in the latter two studies peripheral temperature and conductance were also recorded. An audio stressor was introduced in the first three studies to evaluate the stability of the altered mood of the individuals.

Considerable mood alterations were …


Biomechanical Study Of Performance Of A Plugged Femoral Implant Coupled With A Trochanter Cable System Using Finite Element Analysis, Deanna Yvonne Carstarphen Aug 1999

Biomechanical Study Of Performance Of A Plugged Femoral Implant Coupled With A Trochanter Cable System Using Finite Element Analysis, Deanna Yvonne Carstarphen

Theses

A Finite Element Analysis was conducted to determine the effect of a plug on the performance of the critical section of a femoral implant coupled with a trochanter cable grip system. The critical section was defined near the proximal end of the stem where a hole was designed for the purpose of attaching the cable grip system. Two models were generated for the analysis. One consisted of the critical section with the grip cables and a plug filled in the hole and the other was without the plug. The models were based on design specifications provided by Howmedica Incorporated. Two …


Study Of The Effects Of Deuterium Implantation Upon The Performance Of Thin-Oxide Cmos Devices, Sumit Kishore Aug 1999

Study Of The Effects Of Deuterium Implantation Upon The Performance Of Thin-Oxide Cmos Devices, Sumit Kishore

Theses

The use of ultra thin oxide films in modem semiconductor devices makes them increasingly susceptible to damage due to the hot carrier damage. Deuterium in place of hydrogen was introduced by ion implantation at the silicon oxide-silicon interface during fabrication to satisfy the dangling bonds. Deuterium was implanted at energies of 15, 25 and 35 keV and at a dose of 1x1014/cm2. Some of the wafers were subjected to N2O annealing following gate oxide growth. It was demonstrated that ion implantation is an effective means of introduction of deuterium. Deuterium implantation brings about a …


Emissivity Measurements And Modeling Of Silicon Related Materials, Vijay Krishnamurthy Aug 1999

Emissivity Measurements And Modeling Of Silicon Related Materials, Vijay Krishnamurthy

Theses

The objective of the thesis was to study the radiative properties of silicon related materials for applications in rapid thermal proceesing. In particular, three distinct materials have been considered - Silicon, SIMOX and Tantalum.

The research highlights are Establishment of spectral emissometry as a novel, reliable and reproducible technique for a) Determination of wavelength and temperature dependent reflectivity, transmissivity, emissivity of silicon related materials and structures. The emissometer operates in the wavelength range of 1-20µm and temperature range of 300-1200K. b) Establishment of methodoligies to obtain the frnndemental constants. Effects of wavelength, temperature, total available free carriers by doping types …


Modeling Of A Permeable Reactive Barrier, Guatam C. Ijoor Aug 1999

Modeling Of A Permeable Reactive Barrier, Guatam C. Ijoor

Theses

The focus of the presentstudy was centered on the modeling analysis to support the Permeable Reactive Barrier (PRB) design. The flow model formulated to simulate the Permeable Reactive Barrier System integrated the available geologic, hydro geologic and geo-chemical data from numerous recent installations to simulate a subsurface ground water scenario.

Different generic cases that a PRB system would fall into were identified based on its utility and aquifer conditions and then employed to produce different model adaptations. The different simulation codes and interfaces were evaluated, and the most expedient of them was used to simulate the Model.

The simulations were …


Mutual Interference Investigation Of Cebus And X-10 Powerline Signaling, Sajid Pallithotungal Aug 1999

Mutual Interference Investigation Of Cebus And X-10 Powerline Signaling, Sajid Pallithotungal

Theses

Powerline control signaling using CEBus has great potential towards inexpensive home automation. CEBus transmits at 10 kBps using spread spectrum in the 100-400 kHz band while X-l0 sends 60 Bps using bursts of 120 kHz carrier on the power line. However, these two signals may destructively interfere when present simultaneously. X-10 is narrow band and interferes with the CEBus spread spectrum signal. This thesis looks into the mutual interference patterns of Power Line CEBus communication in the presence of X-l0 module signaling and visa versa. The investigation encompasses a series of tests and measurements on a Power Line CEBus-X10 test …


Chemical Volatilization Of Heavy Metals For Waste Separation And Real Time Metals Analysis, Mohammad Nasr Ul-Alam Aug 1999

Chemical Volatilization Of Heavy Metals For Waste Separation And Real Time Metals Analysis, Mohammad Nasr Ul-Alam

Theses

One of the major challenges in environmental analysis concerns the rapid and sensitive detection of metals emitted from combustion stacks. An interesting concept for real time analysis is to convert airborne metal oxide particles in a flow reactor into relatively volatile compounds of a single class, and then analyze in the gas phase. In this project, kinetics of chemical volatilization reaction between Sb2O3 and HCl was investigated. To achieve this a laboratory volatilization flow reactor was built and data was collected for the volatilization reaction in terms of conversion, inlet and outlet concentrations and flow rates. A …


Variable Gain Control Of Brushless Dc Motor Control With Low Resolution Sensors, Chung-Hsiang Wang Aug 1999

Variable Gain Control Of Brushless Dc Motor Control With Low Resolution Sensors, Chung-Hsiang Wang

Theses

In this work, feasibility of using low cost, low resolution sensor for high performance brushless dc (BLDC) motor speed control is investigated. Conventional control, using a tachometer or high resolution encoder, suffers from drawbacks such as high cost, large physical volume, and high sensor processing bandwidth. On the other hand, sensorless BLDC motor, appealing in its hardware simplicity, does not provide sufficient fast performance. Using a standard low resolution sensor, such as a hall sensor or commutation encoder, a compromise between cost and performance can be obtained. However, the use of a low resolution sensor does pose a challenge to …


Adaptive Interference Cancelation Techniques For Multicarrier Modulated Systems, Matthijs A. Visser May 1999

Adaptive Interference Cancelation Techniques For Multicarrier Modulated Systems, Matthijs A. Visser

Dissertations

Current wireline systems and wireless broadcasting systems employ multicarrier modulation (MCM). This includes the high-rate digital subscriber line (HDSL), digital audio broadcasting system (DAB) and the digital terrestrial television broadcasting system (dTTb). Multicarrier modulation is also envisioned for high-speed indoor wireless local area networks (WLAN). Additionally, multicarrier code division multiple access (MC-CDMA), a hybrid of orthogonal frequency division multiplexing (OFDM) and CDMA, is proposed for the downlink (base-to-mobile) of a 3rd generation wireless system as part of the IMT-2000 standardization process.

The performance of an MC-CDMA system--similar to a direct sequence CDMA (DS-CDMA) system--is limited by the presence of multiple …


Chemical Reactions And Mass Transport In Emulsion Liquid Membrane, Huifang Fan May 1999

Chemical Reactions And Mass Transport In Emulsion Liquid Membrane, Huifang Fan

Dissertations

Emulsion liquid membrane (ELM) systems are an important technique for wastewater cleanup. For this purpose, emulsion globules are dispersed in wastewater (external phase), each emulsion globule consisting of many tiny aqueous droplets (internal phase) enclosed in oil (membrane phase). Hazardous chemicals in the wastewater are transported into the internal droplets by mass transfer mechanisms.

Since Li first invented an ELM system in the 1960s, much research effort has been devoted to experimentally finding the optimal conditions for ELM recovery of various chemicals. Such studies would have benefited greatly from the guidance of mathematical models, especially those that provide analytical predictions. …


Long Term Risks Associated With Brownfield Containments, Shailesh Shirish Chirputkar May 1999

Long Term Risks Associated With Brownfield Containments, Shailesh Shirish Chirputkar

Dissertations

The sites at which the development is hindered by real or perceived contamination are called as Brownfield sites. It is a common trend in industry to develop these types of sites with surface and peripheral containments. It might prove unwise to develop the sites in this manner from a long term perspective without considering the associated risk. Because of this, a model has been proposed for long term risk assessments of brownfield containments.

Objectives of this study were to develop a contaminant transport model for flow of contaminants towards the surface and peripheral containments inside the site, a model for …


Utilization Of Processed Fly Ash In Mortar, Walairat Bumrongjaroen May 1999

Utilization Of Processed Fly Ash In Mortar, Walairat Bumrongjaroen

Dissertations

Grinding process is introduced to provide fine particles of coal fly ash that enhances the strength gain of cement mortars. It is discovered that grinding can make all the studied fly ashes more suitable for concrete use at higher replacement value than previously anticipated even when the effect of high carbon content is considered.

In this study, new mechanisms for strength gain of fly ash mortars are proposed. They are dispersion and nucleation, which are results from the presence of fly ash in the cement mortar. These effects are shown to enhance the hydration of cement. The pozzolanic action of …


A Methodology For Solving The Network Toll Design Problem, Mei Chen May 1999

A Methodology For Solving The Network Toll Design Problem, Mei Chen

Dissertations

Congestion pricing has been regarded as an efficient method to reduce network-wide travel cost. In this dissertation, a methodology for toll design is developed to provide policy-makers with suggestions on both where to charge tolls and how much the tolls should be. As opposed to the traditional approach of marginal social cost pricing, this methodology is capable of dealing with the more realistic case, in which only a small number of links can be tolled. Furthermore, this methodology is expanded to accommodate multiple user groups.

The toll design problem can be formulated using both deterministic and stochastic route choice models. …


Physical And Geotechnical Characterization Of Water Treatment Plant Residuals, Swamy C. Basim May 1999

Physical And Geotechnical Characterization Of Water Treatment Plant Residuals, Swamy C. Basim

Dissertations

The study of Water Treatment Plant (WTP) residuals is of recent origin and very little information is available in literature regarding these residuals. These waste materials have high solids contents, even in the mechanically dewatered condition, making it difficult to handle. These, along with stringent environmental regulations have forced the water utilities to look for new disposal options for these residuals. For this purpose as well as for evaluating suitable options for the beneficial reuse of residuals, it is essential to characterize WTP residuals.

As the dewatered residuals are plastic, the researcher may be prompted to treat these materials as …


On Scheduling Input Queued Cell Switches, Shizhao Li May 1999

On Scheduling Input Queued Cell Switches, Shizhao Li

Dissertations

Output-queued switching, though is able to offer high throughput, guaranteed delay and fairness, lacks scalability owing to the speed up problem. Input-queued switching, on the other hand, is scalable, and is thus becoming an attractive alternative. This dissertation presents three approaches toward resolving the major problem encountered in input-queued switching that has prohibited the provision of quality of service guarantees.

First, we proposed a maximum size matching based algorithm, referred to as min-max fair input queueing (MFIQ), which minimizes the additional delay caused by back pressure, and at the same time provides fair service among competing sessions. Like any maximum …


On-Line State And Parameter Estimation In Nonlinear Systems, David A. Haessig May 1999

On-Line State And Parameter Estimation In Nonlinear Systems, David A. Haessig

Dissertations

On-line, simultaneous state and parameters estimation in deterministic, nonlinear dynamic systems of known structure is the problem considered. Available methods are few and fall short of user needs in that they are difficult to apply, their applicability is restricted to limited classes of systems, and for some, conditions guaranteeing their convergence don't exist.

The new methods developed herein are placed into two categories: those that involve the use of Riccati equations, and those that do not. Two of the new methods do not use Riccati equations, and each is considered to be a different extension of Friedland' s parameter observer …


Optimization Of Urban Traffic Control Strategies By A Network Design Model, Wu Sun May 1999

Optimization Of Urban Traffic Control Strategies By A Network Design Model, Wu Sun

Dissertations

The efficiency of congested urban transportation networks can be improved by implementing appropriate traffic control strategies, such as signal control timing, turning movement control; implementation of one-way traffic policies, lane distribution controls etc.. In this dissertation, the following strategies are addressed: 1) Intersection left turn addition/deletion, 2) Lane designation,. and 3) Signal optimization.

The analogy between the network design problem (NDP) and the optimization of traffic control strategies motivated the formulation of an urban transportation network design problem (UTNDP) to optimize traffic control strategies. An UTNDP is a typical bi-level programming program, where the lower level problem is a User …


Development Of Computer Model And Expert System For Pneumatic Fracturing Of Geologic Formations, Brian Michael Sielski May 1999

Development Of Computer Model And Expert System For Pneumatic Fracturing Of Geologic Formations, Brian Michael Sielski

Dissertations

The objective of this study was the development of a new computer program called PF-Model to analyze pneumatic fracturing of geologic formations. Pneumatic fracturing is an in situ remediation process that involves injecting high pressure gas into soil or rock matrices to enhance permeability, as well as to introduce liquid and solid amendments. PF-Model has two principal components: (1) Site Screening, which heuristically evaluates sites with regard to process applicability; and (2) System Design, which uses the numerical solution of a coupled algorithm to generate preliminary design parameters.

Designed as an expert system, the Site Screening component is a high …


Fdtd-Based Full Wave Co-Simulation Model For Hybrid Electromagnetic Systems, Tong Li May 1999

Fdtd-Based Full Wave Co-Simulation Model For Hybrid Electromagnetic Systems, Tong Li

Dissertations

In high-frequency ranges, the present electronic design automation software has limited capabilities to model electromagnetic (EM) systems where there are strong field effects influencing their characteristics. In this situation, a full-wave simulation tool is desired for the analysis and design of high-speed and non-linear EM systems. It is necessary to explore the interaction between the field and electronic components during a transient process when field effects are more significant. The finite-difference time-domain (FDTD) technique receives growing attention in the area of EM system analysis and simulation due to its simplicity, flexibility and robustness. It is a full-wave simulation method that …


Observers For Discrete-Time Nonlinear Systems, Walter D. Grossman May 1999

Observers For Discrete-Time Nonlinear Systems, Walter D. Grossman

Dissertations

Observer synthesis for discrete-time nonlinear systems with special applications to parameter estimation is analyzed. Two new types of observers are developed. The first new observer is an adaptation of the Friedland continuous-time parameter estimator to discrete-time systems. The second observer is an adaptation of the continuous-time Gauthier observer to discrete-time systems. By adapting these observers to discrete-time continuous-time parameter estimation problems which were formerly intractable become tractable.

In addition to the two newly developed observers, two observers already described in the literature are analyzed and deficiencies with respect to noise rejection are demonstrated. improved versions of these observers are proposed …


Fundamentals Of Dry Coating In Fluidized Bed, Rakesh Iyer May 1999

Fundamentals Of Dry Coating In Fluidized Bed, Rakesh Iyer

Theses

This thesis is devoted to the study of a novel dry coating method in fluidized bed - Dry Coating of Particles in Spouted bed (DCPS). The main objectives of this work were to study the feasibility of the process, both quantitatively and qualitatively, and to compare the results with coating by conventional mechanical mixing. Aerosol mechanics is applied to account for the following: 1) collision between the guest and host particles in a spouted bed (analysis of guest-host particle inertial fluid-dynamic interaction), and 2) to show how collision efficiency of guest particles with host particles affects the coating efficiency. An …


Multi-Lifecycle Assessment Design Tools And Software Development, Ji Jin May 1999

Multi-Lifecycle Assessment Design Tools And Software Development, Ji Jin

Theses

This thesis introduces the concept of Multi-lifecycles and a Multi-lifecycle assessment (MLCA) methodology for evaluating the energy consumption and environmental emissions of a product. MLCA quantifies materials, energy, and environmental burdens associated with end-of-life options, as well as obtains the value of returning parts and materials back to use, through demanufacturing, reengineering and remanufacturing.

A Multi-lifecycle Assessment software is developed as a tool to implement MLCA methodologies. By this software, one can practice a full life-cycle analysis on a product, or compare the environmental impacts of different products. Detailed designs on MLCA software including the databases, user interfaces, and algorithm …


Design And Engineering Of A Tensile Fabric Structure, Jairo Rios May 1999

Design And Engineering Of A Tensile Fabric Structure, Jairo Rios

Theses

Fabric structures are designed in an iterative process between architect and engineer, analysis input and output, and detail and patterning. There are three main steps in designing a fabric structure: shape finding, loading, and patterning/ detailing.

Shapefinding consists of finding the shape of the fabric where the fabric forces are in equilibrium. This type of structure is geometrically nonlinear which require iterative analysis to converge on a unique solution.

The loading of the structure is similar to that of any conventional structures. The departure is in the major effects that suction and ponding have on fabric surfaces.

Usually the details …


Coagulation And Disinfection By-Products Formation Potential Of Dissolved Organic Matter Fractions, Neeraj S. Pipada May 1999

Coagulation And Disinfection By-Products Formation Potential Of Dissolved Organic Matter Fractions, Neeraj S. Pipada

Theses

Both the proposed United States Environmental Protection Agency (USEPA) Disinfectants- Disinfection By-Products and Enhanced Surface Water Treatment rules have provisions for minimizing the formation of undesirable precursors of disinfection by-products (DBPs) in drinking water Natural Organic Matter (NOM) contains many of the precursors to the DBPs formed following disinfection of drinking water. DAX-8 resin procedures were used to isolate and fractionate NOM into six dissolved organic matter (DOM) fractions; Hydrophobic acid (FA), base (FB), neutral (FN), and hydrophilic acid (PA), base (PB) and neutral (PN). Aluminum sulfate (alum) jar coagulation tests were performed to determine the optimum coagulation ranges of …


Vibration Control On Linear Robots With Digital Servocompensator, Roger Kobla Kwadzogah May 1999

Vibration Control On Linear Robots With Digital Servocompensator, Roger Kobla Kwadzogah

Theses

Control application for active damping of structural vibrations and acoustic noise in mechanical systems is one of the engineering fields that can benefit from advances made in digital signal processors. This thesis project is one such application. It is about a vibration control at the loading point of a high speed linear robotic workcell. A lead zirconate titanate piezoelectric ceramic is used as the actuator and an accelerometer provides the sensing. From experimentally measured frequency response of this system, a shaping filter is designed and added on. The reshaped system is fitted with a third order transfer function design model. …