Digital Commons Network^™

Mathematical Modeling And Computer Simulations Of Biodenitrification In Batch And Sequencing Batch Reactors, Sugata Sanyal

Theses

Mathematical models have been derived for describing biodegradation of ni¬trate and nitrite in an anaerobic environment. Monod model for nitrate and Andrews model for nitrite were used as kinetic models. Experimental data from literature suggest that nitrate is not an inhibitory substance, while nitrite is not only inhibitory but it may also have a toxic effect on the biomass. The models were brought in dimensionless form in order to reduce the number of parame¬ters. Biodegradation was mathematically described for a batch, and a sequencing batch mode of operation. Computer programs were developed for numerically simulating the process. Some of the …

The Oxidation Of Methylene Chloride Over Manganese Dioxide Catalyst, Jun Du

Theses

This research presents results from a study with the goal of using a transition metal oxidation catalyst, manganese dioxide (MnO₂) I to convert low concentrations of methylene chloride (CH₂Cl₂) in air and in a methane/air stream into CO₂, H₂O and HCl. Our objectives were to determine the oxidative effectiveness of the catalyst and its durability under the corrosive exposure to chlorine, HCl and other likely stack gas contaminants.

Experiments were carried out in a tubular packed bed integral reactor using gas chromatographic (FID and TCD) analysis for chlorocarbons and non-dispersive …

X-Ray Powder Diffraction, Scanning Electron Microscopy And Energy Dispersive Spectroscopy Studies Of Soil Containing Chromium Immobilized By Microwave Treatment, Nagui Ibrahim

Theses

The orientation of soil contaminants such as chromium is altered during microwave heating. The SEM and EDS were utilized in the study. The nature of the orientation is related to the heating time. This results in immobilizing the contaminant in leaching tests. The non-leachibility was related to the reactivity of the chromium salt with the soil hematite phase (Fe2O3) during the microwaving. This was proved By the X-ray diffraction analysis. The spectrums obtained from 30 and 60 minutes microwaved samples were identical in the crystal phases and were significantly different from the contaminated unheated sample.

Eeg Mapping Using The Personal Computer, Zhuan-Zhang Pei

Theses

An approach for brain electrical activity mapping using a personal computer has been investigated to enhance the visibility of the EECs. An automatic procedure from data acquisition to the final mapping has been developed for on-line or off-line data processing, in which a table-look-up technique has been introduced to eliminate redundant processing. The power spectra in different EEC frequency bands for four electrodes are coded into 15 colors and mapped on a color monitor. The data correspondings to the areas between electrodes are interpolated by the surface spline method. The mapping speed and smoothness has been optimized. An experiment has …

Mathematical Modeling And Simulation Of The Progression Of Aids, Anju H. Nagpal

Theses

Acquired Immunodeficiency Syndrome (AIDS) caused by Human Immunodeficiency Virus (HIV) is a pernicious disease acknowledged as a world health problem. One of the major issues in the study of AIDS is understanding the manifestation and the progression of the disease following the transmission of HIV. Unfortunately, the present state of biological knowledge does not yet give us a reliable means of evaluating these phenomena. A simulation approach is, therefore, extremely useful in predicting the various phases of the deteriorating physiological status of the patient. In the present study we have focused on the development of a mathematical model of the …

The Accreditation Of Professional-Technician Occupations, Michael William Allgaier

Theses

This study investigates the relevance of different elements of accreditation as applied to professional and technical occupations. The impact of essential elements of typical accreditation programs on the outcome of the credentialing process is studied. The credentialing process is viewed in the context of how it affects the public safety, health and well being of society. The health, legal, engineering, and educational professions are analyzed to form a conventional professional base of comparison with the emerging professional-technical occupations in the nuclear industry, especially nondestructive examiners.

Nurses, attorneys, engineers, and teachers accreditation programs are analyzed for their strengths and areas for …

An Implementation Of Mht Algorithm For Adaptive Transform Coding Of Speech, Peter Battenschlag

Theses

The Modified Hermite Transform (MHT), a suboptimum block transform scheme, is implemented on a TMS320C25 signal processing system with the objective of reducing the redundancy in speech signals and transmit a quantized vector representation at bitrates as less as 0.5 bits per sample.

The generation of the Hermite polynomials with a binomial and several first order IIR filter structures is presented focusing on the fact that no muliplications are required which simplifies the MHT algorithm considerably.

An assembler program performs forward and inverse transformation together with a vector quantization using adaptive bitallocation based on short-time statistics for the transform coefficients. …

Removal Of Nitric Oxide From Flue Gas With Ferrous Cysteine Solutions, Chun-Chiao Chou

Theses

The removal of NO from flue gas with aqueous ferrous cysteine solution as the reducing agent was discovered by S. G. Chang et al. (1988), at University of California, Berkeley. The purpose of this research is to extend the experimental works done by Chang et al., and to find methods to minimize the problems associated with the sensitivity of the medium to oxygen gas and emission of nitrous oxide, a greenhouse gas. The main objective was to determine the feasibility of using ferrous cysteine in the treatment of NOx emissions from incinerators. In the present study, it was found that …

Finite Element Stress Analysis Of Engine Piston, Anil Nanalal Mistry

Theses

In this analysis, Ford Motor Company's, modular engine seriespiston was selected for the analysis purposes. The engine has a capacity of 4.6 liter, V-8 cylinder and with 2 valves.The piston is made of aluminum alloy material Z-16-T6. A three-dimensional finite element model was created to analyze the piston. The model, which contains only the quarter section of the piston due to loading symmetry and geometry, was used to calculate operating temperatures and the corresponding thermal expansion. Operating stresses due to thermal and mechanical loads were also calculated. The accuracy of the model was verified by material data published in the …

Modeling Packed Bed Catalytic Reactors, Jing Yang

Theses

Catalytic reactors provide a potentially important tool in the control of process emissions to the environment. This work provides a detailed chemical/physical model for analysing the operational characteristics of packed bed catalytic reactors. Mass, momentum, and energy conservation equations are written for the gas and solid phases. Heterogeneous and homogeneous reactions are used to convey the required stoichiometry, reaction rate, and heat release rate. Reaction in each phase is modeled as a one-step, global reaction. Heat and mass transfer, fluid friction, and axial heat conduction in the solid phase are modeled using suitable literature correlations. The resulting non-linear, first-order differential …

A Theoretical Model For Radio Attenuation Inside Buildings, Kyu-Sung Kim

Theses

Research to expand the capability of indoor, portable, radio frequency links for voice and data transmission is being pursued worldwide. Sophisticated communication systems using digital portable radio telephones have been proposed. To accomplish this goal, it is necessary to ascertain the attenuation of electromagnetic signal propagation inside buildings. Because modeling of the indoor environment at radio frequencies is very complicated, most publications document experimental results. In this study,. a theoretical model is proposed for predicting path loss inside buildings. The theory involves a waveguide model of the indoor environment which permits a rigorous modal solution similar to that developed by …

Development Of Air-Break Circuit Breaker, Ravi Kanth Korrapati

Theses

This thesis describes the development of an Air-Break circuit breaker, for Heinemann Electric Co., New Jersey, using I-DEAS CAD software. The physical properties obtained from the software, for the components of the armature assembly and the contact arm and the carriage, are used in determining the initial forces on a helical delay spring and in calculating accelerations of links in the trip mechanism. The trip mechanism is a four-bar mechanism with a spring as a coupler. Two second order differential equations define the motion of its links, the contact arm and the carriage. A time history of the links is …

Chemical Activation Analysis Of The Reaction Of Methyl, Ethyl, Propyl And Butyl Radicals With O2, Hsing-Hui Yu

Theses

The addition reactions of methyl, ethyl, propyl and butyl radicals with molecular oxygen to form the energized adducts CH3OO#, CCOO#, CCCOO#, C₂COO#, C*CCOO#, CCCCOO#, CCCOO.C#, C2CHCOO#, C₃C00#, C*CCCOO#, CC*CCOO# and C*CCOO.C# and the reactions of the adducts to varied products have been analyzed using the bimolecular version of the quantum Rice-Ramsperger-Kassel (QRRK) theory. The analysis encompassed a temperature range from 200 to 2000 K and pressures between 0.001 to 10 Atm in argon (CH₃ + O₂ reaction only), helium and nitrogen bath gases. The calculations satisfactorily explain the experimentally observed rate constants for loss …

Temperature Dependent Current-Voltage Characteristics In Thin Sio2 Films, Jin Zhao

Theses

An analysis of the Fowler-Nordheim tunneling (FNT) theory and its application to temperature dependent current-voltage characteristics, of very thin films of SiO₂ on silicon, is presented. The final results are believed to provide the most complete examination of FN emission theory and predict the breakdown electric field in thin SiO₂ films. The role of the roughness, at the Si-SiO₂ interface, in determining the FNT current and breakdown mechanisms in metal-oxide-semiconductor (MOS) structures are also discussed.

Teaching Mechanical Design Using The Axiomatic Approach, Lisa E. Hailey

Theses

Many authors on the subject of design state that it cannot be taught, it must be learned through experience. This thesis offers a method in which design can be taught to senior mechanical engineering students. The axiomatic approach to design, authored by Dr. Nam P. Suh of the Massachusetts Institute of Technology, states that all good designs follow two axioms, the independence axiom and the information axiom. By teaching students to use these axioms, and the corollaries and theorems derived from the axioms, educators can teach students the basic concepts of good design.

To show how this approach can be …

Investigation Of Material Erosion By Abrasive Water Jet Cutting, Fang Hu

Theses

This study is concerned with the investigation of material erosion phenomena occurring in the abrasive waterjet (AWJ) cutting process.

A series of scratches were generated by the abrasive waterjet on the polished surface of aluminum samples. The tests were carried out at different traverse speeds, abrasive flow rates, diameters of sapphire nozzles, diameters of carbide tubes and initial abrasive particle sizes. Material volume loss in the erosion zone was measured directly or calculated by the use of the suggested mathematical models. An analysis of experimental results enabled us to introduce a new process criterion, particle distribution density, which determines the …

Simulation Of Random Packing Of Hard Spheres Using Monte Carlo Method, Sung-Ho Park

Theses

A computer based method of generating a random packing of hard spheres is described. Using a Monte Carlo method as employed in the field of Computational Statistical Physics, packing of hard spheres are generated and analyzed.

The mean packing fractions for the present assemblies of 1000 spheres are 0.555±0.015 after pouring and 0.582±0.018 after 10 cycles of shaking. These values are approximately 5 to 6 per cent lower than the experimental results of G.D. Scott[30], but similar with the result of Visscher & Bolsterli [17].

The mean coordination numbers are 5.97 and 6.33 for the pouring and shaking case, respectively. …

Application Research On Wastewater Reuse For Petrochemical Refining Industry In Taiwan, Lih-Shyan Lee

Theses

Nowadays water conservation and pollution abatement are needed to provide increasingly higher levels of treatment for industrial wastewaters.

Reducing treatment costs give us the incentive to minimize the volume of Wastewater effluent. Also, the national goal of zero discharge of pollutants to the waterways by 1985 provided further incentive -to minimize the flow of wastewaters.

A successful treatment of the wastewater discharged from the secondary effluent of the petroleum refinery plant to economically acceptable conditions offers a challenge to our technology.

Through this research, it is concluded that the excellent effluent water qualities produced from filtration and granular activated carbon …

Concept And Analysis Of The Application Software Development Pool, Paul Walter Bette

Theses

This study investigated a new organizational structure within the data processing field. In an attempt to curb job turnover and improve job satisfaction within a typical application software development environment, the concept of the Application Software Development Pool (ASDP) was developed. To identify differences and employee reactions to implementing ASDP's organizational structure versus a more conventional data processing organizational structure, 15 employees participated in a conventional DP group and 15 were assigned to the ASDP group. Job satisfaction questionnaires were distributed both before and after the six month implementation period. Data analysis revealed significant differences between the two groups. The …

Analytical And Experimental Study Of Robotic Peg-In-Hole Insertion, Yilun Jia

Theses

A mathematical model of robotic peg-in-hole insertion, which relates insertion force and moment to manipulator compliance and geometric constraints, is presented. Based on this model, the effects of manipulator compliance and geometric and positional parameters on the insertion are studied. The complete expressions for determining the insertion forces and moment as well as the peg kinematics are derived. The study is helpful to reducing insertion force and moment and avoiding possible jamming during the insertion process. The model is verified experimentally on the IBM 7540 robot.

Three-Dimensional Stress Analysis Of The Femoral Midshaft Utilizing Computed Tomography And Finite Element Analysis, Peter F. Marion

Theses

Recent advances in computer technology have provided both the medical community and biomedical engineers with a method for noninvasively evaluating the internal structure in a way not previously possible. A three-dimensional finite element model of a midshaft section of the femur was generated, utilizing Computed Tomography scan data. The CT scan data file was introduced into an edge-detection algorithm and a file of geometric edge data was generated. This edge data was introduced into a solid modeling Computer-Aided Engineering software package to produce a three-dimensional solid model. A mesh generation procedure was then used to create a three-dimensional finite element …

Adaptive Fir Digital Filter Design And Simulation In The Noise Reduction System, Jack Jiabing Pang

Theses

The adaptive FIR digital filter is designed to suppress the noise in the tape recording and audio communication systems. The cutoff frequency of the digital FIR filters can be varied adaptively depending on the energy level of the input signal. In audio communication, especially, in tape recording systems, the noise obviously gets much bigger, when the frequency band of the system increases. The noise reduction system makes use of a phenomenon called masking, where the big signal-to-noise ratio makes human ears not sensitive to the noise. In a constant interval time, the system detects the signal level and compares the …

Computer Integrated Manufacturing : A Systems Approach For Small Manufacturing Enterprises, Sanjeet Jagdish Patel

Theses

This work is dedicated to small manufacturing enterprises seeking to explore Computer Integrated Manufacturing (CIM) technology, which is the recent trend in the manufacturing world. The main therie of this thesis is to improve productivity, product quality and reliability and reduce costs by integrating various disciplines.

Generic manufacturing functions including order entry, inventory control, manufcturing planning and control, automated drafting, direct numerical control etc. were enhanced by the effective utilization of low end workstations grouped together into a network and equipped worth industry standards software.

The introduction of computers into a manually resourced system yielded significant results such as reduction …

Sputter Deposition And Characterization Of High Tc Superconducting Thin Films, Vipulkumar Patel

Theses

Preparation of thin superconducting films by direct RF sputter deposition on Si, MgO, SrTiO₃ and quartz substrates and silver and Sl3N4 buffer layers (deposited on silicon substrates) was studied. To study resistance versus temperature characteristics of thin films and bulk materials, a computerized measurement system was developed. 1-1.5 pm thick YBaCuO films deposited on Si₃N₄/Si were found to be insulating with room temperature resistance higher than 236KΩ, while films with Ag as a buffer and/or a passivating layer exhibited metallic behavior with room temperature resistances lower than 700mΩ. The area directly under the 2.25 inches …

Treatment Of Trucking Station Wastewater By Two-Phase Anaerobic Digestion System And Rotating Biological Contactor, Tzu-Wen Uen

Theses

The wastewater produced as a result of trucking station activities has some major characteristics such as high COD (26,880 mg/1-42,925 mg/1) and BOD (12,278 mg/1-7,265 mg/1), high COD to BOD ratio (3.49-3.69), high pH range (3.72-11.7), and high grease content (480 mg/1-1,960 mg/1). Therefore, prior to any treatment, it is important to provide some sort of pre-treatment for pH adjustment and grease/oil removal.

The present laboratory investigation has indicated that successful treatment and purification of the subject wastewater is possible using two-phase anaerobic digestion system followed by rotating biological contactor. More than 90% of both COD and BOD was removed …

Development Of A Flexible Control And Automated Data Acquisition System For Wear Testing, Wen-Long Yao

Theses

The purpose of this work is to develop a flexible control and automated data acquisition system for wear testing procedure. A programmable logic controller (PLC) control philosophy and PC-based automated data acquisition system (DAS) were designed and organized for the wear testing machine in Surface Engineering Laboratory of Mechanical Engineering Department. The designed and performed separation of control and acquisition strategies saved a lot of engineering interface communication time. Several instrumentations and mechanism designs, such as selected RTD sensor, modified testing shoe for RTD installation, designed controlled lubrication mechanism, and designed load-unload mechanism, have been performed to fulfill the concerned …

Simulation And Design Of Field Emission Diode, Yun Yuan

Theses

A new generation of microelectronic devices utilizing vacuum field emission cathodes becomes surging interest in recent years. This paper concentrates on the study of the field emission diode — a basic vacuum microelectronic device. The field emission efficiency, current spatial distribution and time dispersion of conical tips and wedges of various geometrical shapes are compared and calculated by analytical methods and computer simulations. Two field emitter heating effects, namely the Joule heating and Nottingham effect, are discussed theoretically. All the simulation results in this paper are performed on 386 based personal computer. The limiting memory space of PC induced simulation …

Studies Of Nitro-Pah On Ambient Air Particulate Matter, Yadan Wang Chen

Theses

A rapid, simple method for routine trace analysis of four isomeric nitropolycyclic aromatic hydrocarbons (nitro-PAH) (1-nitropyrene, 2-nitropyrene, 2-nitrofluoranthene and 3-nitrofluoranthene) in ambient air particulate matter is described. Two types of air particle sample (TSP and IP10) were collected and particle extracts were prefractionated by thin layer chromatography and the appropriate zones of interest analyzed by reversed-phase HPLC with UV and fluorescence detection. The study of Zn/Si post-column reaction chamber and oxygen scrubber for catalytic reduction of target compounds is also described. Six nitro-PAH compounds were identified in TSP and five in IP10 air particle samples. The results of identification and …

Benzo(A)Pyrene Ingested From Composite Meals : Analysis And Method Development Related To Total Human Exposure, Che-Han Hsu

Theses

Polycyclic aromatic hydrocarbons including benzo[a]pyrene (BaP) have been known for many years to be environmental carcinogen. Moreover, B(a)P has often been used as an indi¬cator for the carcinogenic potency of environmental matter. One of its exposure pathways, ingestion, may possibly be more important than other routes, conventionally studied such as inhalation. The purposes of this thesis are 1) to analyze the B(a)P concentrations in weekly composite and some daily meals obtained in the Total Human Exposure to Environmental Substances (THEES) study, 2) to develop techniques which can measure the levels of B(a)P in foods accurately and effici¬ently, 3) to compare …

Synthesis Of Strained Lactams And Study Of Their Energetics And Bonding, Jung-Chou Tsai

Theses

In order to measure nitrogen and oxygen ionization energies of planar and nonplanar lactams, four compounds were synthesized successfully. The comparison of these ionization energies provides a qualitative insight into how the charge distribution of strained lactams varies with molecular geometry. Of special interest was the different ability of amides to exhibit resonance, monitored most sensitively by the core electron energy of nitrogen in the compounds. The nitrogen core (1s) ionization energies for the two nonplanar amides, 1,3-di-tert-butyl aziridinone (405.00 ev) and 1-azabicyclo[3.3.1]nonan-2-one (405.47) each having pyramidal nitrogens, indicated a nitrogen more negative than that in the comparable planar amide. …