Digital Commons Network^™

Analysis Of Random Halftone Dithering Using Second Order Statistics, Eran Steinberg

Theses

An analytical approach is proposed to explain the appearance of unwanted low frequency artifacts during the random dithering halftoning process. The solution uses a theorem which relates the correlation of the input gray level (continuous) signal to the correlation of the output (halftone) binary signal. The numerical solution of the above relationship suggests that: 1. Introduction of low frequency artifacts is inevitable. 2. The effect is enhanced for mean gray levels farther from mid-gray. 3. High frequency information in the input signal is attenuated more than low frequency information.

Threshold Modulation In 1-D Error Diffusion, Katrien Daels

Theses

Error diffusion (ED) is widely used in digital imaging as a binarization process which preserves fine detail and results in pleasant images. The process resembles the human visual system in that it exhibits an intrinsic edge enhancement An additional extrinsic edge enhancement can be controlled by varying the threshold. None of these characteristics has yet been fully explained due to the lack of a suitable mathematical model of the algorithm. The extrinsic sharpening introduced in 1-D error diffusion is the subject of this thesis. An available pulse density modulation(PDM) model generated from a frequency modulation is used to gain a …

Simulation Of An Electrophotographic Halftone Reproduction, Alfonse Nazzaro

Theses

The robustness of three digital halftoning techniques are simulated for a hypothetical electrophotographic laser printer subjected to dynamic environmental conditions over a copy run of one thousand images. Mathematical electrophotographic models have primarily concentrated on solid area reproductions under time-invariant conditions. The models used in this study predict the behavior of complex image distributions at various stages in the electrophotographic process. The system model is divided into seven subsystems: Halftoning, Laser Exposure, Photoconductor Discharge, Toner Development, Transfer, Fusing, and Image Display. Spread functions associated with laser spot intensity, charge migration, and toner transfer and fusing are used to predict the …

Negative Feedback Control Of The Visual System And Systematic Color Vision Model, Yan Liu

Theses

This thesis presents a physiological hypothesis of a systematic negative feedback control mechanism of the human visual system and a corresponding systematic color vision model. This model is based on the physiological hypothesis of systematic negative-feedback control of the visual system and both the stage color vision theory and Land's theory. According to this systematic color vision model, the color vision is processed as described by the stage theory, the negative feedback of the visual system adjusts the sensitivities of the cone photoreceptors and controls the visual system to adapt to the visual surroundings . The dynamic ranges of relative …

Magnetic Resonance Imaging Studies Of The Behavior Of Fluids In Gelatin And Other Porous Materials, Brian J. Antalek

Theses

An application of magnetic resonance imaging to the study of the diffusion of water in gelatin and other materials is described. Gelatin was studied in great detail while plaster, balsa wood, and cement were studied to a lesser degree. Images of the materials at various stages of the diffusion process were recorded and analyzed. In order to properly interpret the imaging signal, the relationships between two intrinsic system parameters, Ti and T2, with the experimental parameters of the study need to be established. In the case of gelatin studies, Ti and T2 times were measured for gelatin samples varying in …

Fault Tolerant Clos Network, Preet Mohan S. Ahluwalia

Theses

Multistage interconnection networks, or MINs, provide paths between functional modules in multiprocessor systems. The MINs are usually segmented into several stages. Each stage connects inputs to appropriate links of the next stage so that the cumulative effect of all the stages satisfies input-output connection requirements.

This thesis deals with a fault tolerant Clos network. The fault tolerance technique involves addition of extra switches per stage to compensate for any switch failure The reliability analysis of both ordinary and fault tolerant Clos networks is presented. The optimal number of extra switches required to get the best reliability results has been analyzed.

Multiresolution Techniques : Laplacian Pyramid Coding And Its Comparison With Subband Coding, Danmei Chang

Theses

The multiresolution pyramid and related structures have been developed as intermediate representations between the purely frequency domain and purely spatial domain. In this thesis. we discuss two important pyramid structures which are often used in multiresolution representation: Laplacian pyramid and subband coding.

Laplacian pyramid. a typical pyramid structure, is studied in detail. By means of software implementation. we obtain a comprehensive understanding of its features and applications in image representation and data compression. Several modifications of pyramid structure are used to compress the data dynamic range, reduce the computational complexity and improve performance. Performance of the conventional Laplacian pyramid and …

Centrifugal Modeling Of Leaking Underground Storage Tanks, Kuo-Neng George Chang

Theses

There are between 2 to 3.5 million Underground Storage Tanks (UST) located through this nation. Most of these tanks store gasoline and fuel oil. Many tanks in fact are or will soon be leaking, thus making them one of the major sources of groundwater contamination in USA. The fate and transport of chemicals from the leaking USTs is estimated from mathematical models. A major difficulty in these modeling efforts has been a crucial lack of information concerning the constitutive relationships governing multiphase contaminant movement.

Centrifugal modeling is an alternative to mathematical modeling, which may give an insight to the problem …

Thermal Desorption Of Organic Contaminant From Sand Using A Continuous Feed Rotary Kiln, Hsien-Tsung Chern

Theses

The purpose of this research was to determine the feasibility of removing organic contaminants from sand by thermal desorption. A continuous feed rotary kiln was designed and constructed to study the thermal desorption behavior of organic contaminant from sand with respect to temperature and residence time, and to develop a mathematical model that will describe this desorption behavior. The model will allow prediction of the desorption rate of an organic contaminant in larger scale rotary kiln desorption system over temperature at a known set of residence time.

In this experiment, sand was uniformly contaminated with a known amount of organic …

Information Handling System With A Personal Computer To Assist In The Manufacturing Of Plastic Parts, Yi Chung

Theses

The ongoing personal computer development has led to its increasing application in manufacturing to improve productivity. Being more aware of this technology, most of these benefits have accrued to large firms. The intent of this thesis is to show that it is equally advantageous for small manufacturing companies to utilize them and show how they can do so.

The field of production control systems is discussed and those areas where personal computers can be applied are emphasized. Forecasting, warehouse management, material requirement planning, and inventory control are the most appropriate. An application example using dBase III plus to write the …

Some Aspects Of Integration Of Classification, Computer Aided Design, Process Planning, And Scheduling Of Flexible Manufacturing Systems, Suresh Godavari

Theses

This work deals with the role, problems and solution technique for integration of Computer Assisted Design, Classification, Process Planning, and Scheduling for a Flexible Manufacturing System. A lark spectrum of rotational and prismatic parts are considered.

A Knowledge-based rough classification and coding system [C&C] has been developed for coding similar parts using a Group Technology [GT] technique. In this module VP-EXPERT and DBase III Plus are used as expert system and database respectively. This module interfaces with a database for the retrieval and selection process.

The code obtained from the C&C system is the basis for the succeeding phases. The …

Deposition Of Particles In A Channel With Gravity And Image Forces, Jing-Shiun Lai

Theses

Deposition of particles in a parallel-plate channel under the influence of inertia, fluid viscosity, gravity and image forces was studied using trajectory method.

A laminar fluid flow of uniform and parabolic (or fully-developed) velocity profiles is assumed and the fluid is suspended with particles having the same velocity as the fluid at the inlet plane. The particles flowing into a horizontal parallel-plate channel have no initial velocity in the vertical direction. The influence of gravity force and image force produces a vertical motion which results in deposition of particles on the channel walls.

A trajectory method was employed to find …

Multiple Expert System, Umesh Kumar Mittal

Theses

In many domains, for example medical diagnosis, there are several sources of knowledge, e.g., several domain experts. These domain experts may have disagreements over some issues in the domain. Research in the area of human decision making suggests that a human decision is not always made based on the advice of a single expert. Many current expert systems, however, expect consistency in their knowledge bases. An expert system does not deliberate by reasoning that "on one hand..." but "on the other hand..." The knowledge engineer, who is not necessarily an expert in the same domain, ensures consistency by eliminating all …

An Efficient Annealing Algorithm For Global Optimization In Boltzmann Machines, Rajendra Sarasakrishna

Theses

This thesis proposes a new annealing algorithm for Boltzmann Machines. This algorithm uses an Exponential Formula for temperature scheduling that produces remarkably better solutions for global optimization. The superiority of the new algorithm is shown by computer simulations of several examples on Boltzmann Machine and its variants. This is also shown to have better properties than algorithms like Generalized Simulated Annealing which possess somewhat similar dynamics.

The Application Of Feedback And Control System Theory To Organizational Modeling, Thomas Miklos Tamas

Theses

A review of the literature showed that relatively little attention has been given to the application of feedback and control systems to management. Since a major function of management is control, scientific management might offer assistance in the form of a more quantitative approach to management control. This thesis suggests one might accomplish this through the application of feedback and control systems.

The application of feedback and control theory to management systems is relatively new, however, literature has shown a trend towards the application of electrical engineering theory to non-engineering topics [Khranovich76]. There has also been some research in the …

Efficient Multiprocessor Scheduling By Mean Field Theory Neural Networks, Pei-Ken Yi

Theses

In this thesis, we develop an optimization method based on Mean Field Theory (MFT) Neural Networks to solve the Task Scheduling problem. The MFT algorithm combines characteristics of the Simulated Annealing (SA) algorithm and the Hopfield neural network. MFT exhibits rapid convergence and at the same time it preserves the solution quality afforded by SA. Since MFT has been successfully used to solve the Traveling Salesman Problem (TSP), a new modification to MFT is also presented which supports Task Scheduling problem. The temperature behavior of MFT during Task Scheduling is approximately analyzed and shown to possess a critical temperature (71,) …

A Study Of Biological Dentrification Of Munition Wastes, Sonia R. Venugopal

Theses

Kinetics of denitrification were studied using a consortium from the Lawrence, Kansas municipal treatment plant. Experiments were conducted in the batch mode, under controlled oxygen and pH conditions. It was found that the Monod model can successfully perdict the experimental results of nitrate depletion. It was also found that when the pH is maintained at values between 7.0 and 8.5, nitrate can be treated in a batch mode without having any significant nitrite presence in the reactor. The experimentally determined kinetic parameters were used in preliminary calculations for sizing a sequencing batch reactor (SBR). An existing mathematical model for the …

Investigations Of Substitution Of Bi And Tl For Rare Earth Elements In Superconducting Rba2cu3oy, Jian Tang

Theses

Substitution of some other elements for rare earth or yttrium in high-T_c superconducting RBa₂Cu₃O_y compounds (R = Y, Nd, etc.) may improve chemical and physical properties of the materials, shed light on the superconducting mechanism of the new materials, and help to find new superconducting materials with even higher transition temperatures.

Bi³⁺ and Tl³⁺ have been reported earlier to result in higher T_c's in the related layer-structure compounds. The effect of electronegativity on superconductivity could be studied if substitution of Bi or Tl for Y or other rare earth elements …

Fast Packet Switching For B-Isdn With Neural Net Control, Ajit K. Chaudhuri

Theses

The concept of integrated network where both the voice packet and data packet are delt with, started taking shape since 1970. Later, Users? demand for communication of data, voice, file, facsimile, image, videotext, videophone, videomovie has also been felt. All these services need bit rate of transmission in the order of 10, even 100 Mbits. An economical way to transmit this higher bit rate, with flexibility of bandwidth, is to treat voice/video in the form of packets and transmit those packets in real time. Studies of this kind of communication is carried out in Broadband ISDN ( BISDN). At this …

A Multimode Index Detecting Sensor For Use In Plastic Concrete, Qiyu Chen

Theses

This thesis describes a microcomputer-based measuring system using a laser diode source, a fiber optic sensor and a microcomputer DMA interface to test and analyze the entrained percentage of air in concrete.

The principle of refraction and reflection of light in optical fibers is applied to detection of air bubbles. Reflected light intensity signals are detected and transferred through a DMA interface to a laptop computer. Analysis of reflected light intensity produces a measurement of the air content of fresh concrete. Accuracy of the system is evaluated through extensive laboratory and field trials.

Thermal Desorption Of Contaminated Soils, Hsi-Ming Sung

Theses

A new method by employing the heating probe for the in-situ cleanup of soils that are contaminated with volatile organic hazardous substances is explored. This investigation is a laboratory simulation that was aimed to evaluate the feasibility of desorption of volatile organic compoumds (VOCs) from soil, and to determine the efficiency of the heating probe for maximum desorption.

Two organic compounds, Trichloroethylene, Carbon tetrachloride, were selected as simulants. The experimental results demonstrate that the removal efficiency range from 97.65% to >99.95% of Trichloroethylene and 98.14% to >99.95% of Carbon tetrachloride can be recovered for a 24 hour interval with a …

Hot : A Timing Optimizer For Hierarchical Vlsi Circuits Using The Charge Conservation Delay Model, Yumei Quan

Theses

The primary benefits of VLSI chips are their high speed, small area, and lower power. These performance attributes are dependent on the quality of chip design. As a result, performance can be optimized by proper design decisions. One of the decisions in chip design is the selection of gate delays and/or transistor sizes (channel width of an MOS transistor).

To optimize the performance of VLSI chips, transistor delay models and optimization algorithms are very important since accurate analytical models for signal delay are essential to replace expensive device level simulation and the high efficient algorithms assist designers in developing high …

Analysis Of Chemical Contaminants In Tissue Samples From Two Species Of Fish, Michael David Reive

Theses

Interaction of marine species with chemical pollutants within the marine ecosystem is extremely complex and difficult to interpret. The purpose of this thesis was to investigate the effect of an exposure of treated municipal wastewater on winter flounder (Pseudopleuronectes americanus) and striped bass (Morone saxatilis). Fish from two locations were exposed to different concentrations of wastewater. Half of the fish from each tank were sacrificed, and the remaining fish were given a depuration period in unpolluted water. Tissue samples were composited, soxhlet extracted and passed through a florisil cleanup column. Gas chromatography, was used to analyze for hexachlorobenzene, hexachlorobutadiene, Aroclor …

N-Cross Coupled Phase Locked Loops, Joseph C. Aboukhalil

Theses

Interference cancelation has been mainly performed using arrays, in an important issue in communication both array and spatial cancelation and time domain approach were used. In array applications, depth of cancelation may dependent on the interferences to background power ratio and their spatial distributions. Also, array cancelers are inadequate when the signals are less than an array beamwidth apart. The latter was dealt with using supperesolution and eigenanalysis methods. Different time domain methods were used in the past. Among them what is termed Cross-Coupled PEL. It is an arrangement of two PLL each one is locked on and tracking one …

A Machine Vision System With Remote Host, Chieyeon Jason Chen

Theses

The modem plays an important role in data communication using the Public Swiched Telephone Network. In this thesis, the modem function is merged into a low cost machine vision system based on the Motorola 68HC11. Evalation Board The system comprises the intelligent machine vision con- troller and a remotely located host computer, such as an IBM-PC. It, supports extra long distance communication capability so that the controller and the host can be anywhere in the world where then is a telephone line. Because of the limit of a 2100 bps modem, soft ware data compression is implemented here to save …

Ct Fan Beam Reconstruction With A Non-Stationary Axis-Of-Rotation, Joseph A. Concepcion

Theses

One important aspect for reconstructing an image using Computed Tomography (CT) is that the axis-of-rotation must pivot at the same point on the reconstruction plane as the x-ray source and CT scanner assembly rotates around the imaged object. This pivot point is used as a reference point for backprojecting pixel values to their proper coordinates. Therefore, reconstructing an image with a non-stationary axis-of-rotation would backproject pixel values to wrong coordinate points, since the reference point is non-stationary for every projection angle.

A convolution filtered backprojection algorithm has been derived for correcting images that were acquired with a non-stationary axis-of-rotation using …

Novel Way Of Sub-Carrier Coherent Detection And Clock Recovery In Fiber-Optic Communications, Narayan Gehlot

Theses

We experimentally demonstrate a novel concept for recovery of a Sub-Carrier and Timing Clock in fiber-optic communication systems using a Wavelength Division Multiplexing technique. The idea is to send a low radio frequency (RF) as a reference pilot from the transmitter to the receiver on a separate laser using the principle of Wavelength Division Multiplexing (WDM). This low frequency signal is taken to be a subharmonic of the subcarrier used to carry information and intensity modulate another laser. Such approach will be expected to generate at the receiver a local oscillator in high coherence with the subcarrier.

We show that …

Anaerobic Biological Treatment Of Incinerator Ash To Immobilize Toxic Metal Residues, Uma Parasar

Theses

In this study, a reliable and inexpensive method for biologically immobilizing toxic heavy metal residues present in very high concentrations in incinerator ash was developed. Desulfovibrzo, a genus of sulfate-reducing bacteria was cultured and treated with combined ash under anaerobic conditions. The carbon source, lactate, and the electron acceptor, sulfate, were provided to the cultures for their normal growth. Since the sulfate reducers utilize organic matter using sulfate as the oxidizing agent, sulfides are the corresponding end products of the reaction. Ash was added to well established cultures of desu f ovibrio. Immobilization of the heavy metals in the ash …

Gas Chromatographic Method For Determination Of 28 Volatile Organic Compounds Emitted From A Sewerage Plant, Yeming Sun

Theses

In this study, 28 volatile organic compounds (VOCs) emitted from the Linden Roselle Sewerage Authority Plant (LRSA) were monitered. The determination by gas chromatography (GC) is presented. This work emphasizes the collection of whole air samples, using a canister-based sampling system with cryogenic concentration. An appropriate temperature program was selected to obtain the best sample separation. The procedure for the identification of 28 standard gas mixture was achieved by comparing the chromatograms of sample with those of the specific groups of target compounds, as well as by comparing the sample with the results from GC Mass spectrometeric analysis. Because of …

Coexistence Of Three Pure And Simple Competitors In Four Interconnected Bioreactors, Ming Wu

Theses

It is known that a homogeneous environment having invariant inputs cannot allow for steady state coexistence of any number of pure and simple competitors. However, it has been proven that two pure and simple competitors can coexist at a steady state in two interconnected chemostats, if the conditions are such that they allow a different species to grow faster in each one of the two vessels. It has been also shown that three pure and simple competitors cannot coexist in three interconnected chemostats, even if the conditions are such that a different population could grow faster (have the competitive advantage) …