Engineering Commons^™

Prediction Of Enthalpies Of Mixing With A Unifac Model, Dinh Dang

Theses

A modified UNIFAC model is used in the correlation and prediction of enthalpies of mixing. The model requires two interaction parameters per group pair and values for 172 such pairs are presented here. Excellent prediction results are obtained with typical errors, in the temperature range of 273°K to 400°K, below 15%. For systems containing cyclic compounds, somewhat poorer results may be encountered.

Three Studies On Airborne Polycyclic Aromatic Hydrocarbons, Carol Sophia Eveleens

Theses

Three studies have been conducted on polycyclic aromatic hydrocarbons found on airborne particulate matter. The first investigation involves the determination of fly ash "activity" in the reaction of two PAHs adsorbed on its surface. Mass spectrometry is used to monitor the exchange of hydrogen and deuterium atoms between anthracene and anthracene-d10. The results indicate that some fly ashes exhibit "activity" in the reactions of PAHs adsorbed on its surface. The second investigation involves the determination of cyclopenta[cd]pyrene (CcdP) and benzo[ghi]flouranthene (BghiF) on samples of airborne particulate material collected from two automobile traffic tunnels. Glass capillary gas chromatography with a precolumn …

Investigations Into Rates And Mechanisms Of Mercury Depuration In The Killifish, Fundulus Heteroclitus, Joanne A. Korpanty

Theses

Metallothionein (MT) and glutathione (GSH) have been shown in mammalian research to play a role in the sequestration and depuration of mercury. The sulfhydryl groups on both these peptides have a strong affinity for mercury, MT for Hg²⁺ and GSH for CH₃Hg⁺. In this study, killifish (Fundulus heteroclitus) were force-fed one piece of squid laced with labelled mercuric nitrate to give a final food concentration of 20 ppm ²⁰³Hg²⁺ and 0.03 -0.05 µg g-1 Hg²⁺ total dose. Most of the mercury, 84.1 ± 12.1% (mean ± standard deviation), is depurated within the …

Characterization Of Tdi-Hema Homopolymer Prepared Via An Immiscible Solvent System. Synthesis And Investigation Of Oligodichloroketene, Manuel Montero

Theses

The objective of this thesis has been divided in two parts.

The first part is subdivided into two areas. First a "Universal" calibration curve for gel permeation chromatography (GPC) was construc-ted using different molecular weight standards of PMMA and MMA-HEMA co-polymers. By measuring the viscosity of the different molecular weight solutions and calculating the Vr, (retention volume), from GPC data, plots of In [ η ] Mw against Vr and In Mw against Vr are obtained. These curves can be used to obtain the molecular weight of any linear (not crosslinked) copolymer by simple measurements of viscosity and GPC data. …

Acrylamide Effects On Nerve Terminal Enzymes, Christopher S. E. Marlowe

Theses

Acrylamide causes a peripehral neuropathy. The biochemical mechanism by which it does so is the subject of intense investigation. One of the principal hypotheses for this mechanism centers on acrylamide's ability to inhibit glycolysis. This study examines the effects of in vivo exposure to acrylamide on the enzymes of the nerve terminal particle, the synaptosome.

A method for measuring glycolytic enzyme inhibition in the synaptosome was developed. Acrylamide (500 mg/kg) was administered to rats intraperitoneally. Synaptosomes were prepared by the method of Dodd et al, and lysed by sonication. GAPDH activity and NSE concentration were measured. GAPDH inhibition measured in …

Pullout Resistance Of Welded Wire Mats Embedded In Soil, Mark R. Nielsen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Welded wire mesh has been used in the past as soil reinforcement in the construction of reinforced soil embankments. Involved in the design of these embankments is the external and internal stability. The internal stability has two failure mechanisms; tension failure and pullout failure of the welded wire mesh.

This paper presents the results of laboratory tests on different sizes of welded wire mats embedded in different types of soils. These tests were performed on mats that are much larger than in previous tests. These tests measured the pullout resistance as a function of the number of embedded wires, the …

Ballistic Transport In Submicron Silicon Mosfets, Perry Joe Robertson

All Theses

No abstract provided.

Improvement Of Deep Tubewell Irrigation Project Performance In Bangladesh, Md. Mirjahan Miah

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A computer model for use in predicting the impact of various improvement options on command area expansion of a deep tubewell irrigation system has been developed. A field study was conducted on 11 selected deep tubewells located at two sites, namely Dhamrai and Thakurgaon, in Bangladesh to collect necessary physical data to provide irrigation engineering insight and a basis for testing and application of the model. The results of the investigation revealed that the actual discharge of most of the deep tubewells was lower than the design or rated capacity. The duration of pump operation in the majority of the …

Tensile Properties Of Aluminium/Polypropylene Laminates, Ashraf Adib Hanna

Archived Theses and Dissertations

No abstract provided.

The Development Of A Microprocessor Controlled Linearly Actuated Valve Assembly, Raymond H. Wall

Mechanical & Aerospace Engineering Theses & Dissertations

The development of a proportional fluid control valve/assembly is presented. This electro-mechanical system is needed for space applications to replace the current proportional flow controllers that use bulky hydraulic or pneumatic actuation systems. The flow is controlled by a microprocessor system that monitors the control parameters of upstream pressure and requested volumetric flow rate. The microprocessor achieves the ·proper valve stem displacement by means of a digital linear actuator. A linear displacement sensor is used to measure the valve stem position. 'Ibis displacement is monitored by the microprocessor system as a feedback signal to close the control loop. With an …

Derivations For Discrete-Time Cumulant Control, Henk Albert Roelant

Electrical & Computer Engineering Theses & Dissertations

Expressions for discrete-time cumulant control systems are derived. These expressions are useful for both control system performance analysis and controller selection. Derivation of the performance cumulant expressions parallels the development for the continuous-time case. Two matrix difference equations based on the first two-cumulants are derived. A heuristic procedure for controller selection using the two matrix difference equations paralleling the procedure for the continuous-time case is developed.

Comparative Heat Load Analysis For A Direct Gain Passive Solar Building, Hong Hu

Mechanical & Aerospace Engineering Theses & Dissertations

A newly erected University Police Safety Building on the campus was constructed with passive solar design features. The slab-on-grade brick building has 3081 square feet of conditioned space, an ample south-facing solar aperture with clerestory and an air-to-air heat pump system. A comparative winter heat load assessment has been made in order to determine the fraction of the heat load which can be met by the winter sun (Norfolk, VA 37°N Latitude), and more importantly to probe differences which result when various heat load estimating methods are employed. Techniques employed included the degree day method·, bin method with and with …

Block Transform Coding Of Presample Filtered Data, Thomas A. Shull

Electrical & Computer Engineering Theses & Dissertations

This dissertation addresses the application of non-adaptive transform coding for bit rate reduction of presampled filtered data. Transform coding is examined as an alternative to conventional pulse code modulation (PCM) for multi-source, fixed rate data acquisition systems. Typical bandlimiting presample filters introduce redundancy into the sequence of data samples. Linear transformation of successive N-length blocks of the data sequence and subsequent binary coding of the resulting components is shown to lead to reduced average bit rate for the same less distortion as PCM.

Four Butterworth filters, two corresponding to eight bit PCM systems, and two corresponding to ten bit PCM …

Shape Optimization For Elastic Hollow Bars In Torsion, Jahau Lewis Chen

Mechanical & Aerospace Engineering Theses & Dissertations

The problem of finding optimal cross-sectional shapes of elastic hollow bars in torsion is formulated and solved numerically. A variational formulation for the state equation is presented, and the material derivative of continuum mechanics is used for the shape design sensitivity analysis. Performance criteria include the bending stiffness, the torsional rigidity, and the weight of the bar. The existence of a keyway, an example of geometric irregularity, can be considered as well. The material can be either isotropic or anisotropic. The finite element method is used for the numerical solution of the variational state equation and is integrated into an …

Finite Element Thermal-Structural Analysis Of Cable-Stiffened Space Structures, Ajay Kumar Pandey

Mechanical & Aerospace Engineering Theses & Dissertations

Finite element thermal-structural analyses of cable-stiffened space structures are presented. A computational scheme for calculation of prestresses in the cable-stiffened structures is also described. The determination of thermal loads on orbiting space structures due to environmental heating is described briefly. Three finite element structural analysis techniques are presented for the analysis of prestressed structures. Linear, stress stiffening and large displacement analysis techniques are investigated.

The three techniques are employed for structural analysis of prestressed cable structures at different prestress levels. The three analyses produce similar results at small prestress. but at higher prestress differences between the results become significant. For …

Design Of Multivariable Feedback Control Systems Via Spectral Assignment Using Reduced-Order Models And Reduced-Order Observers, Preston Ivanhoe Carraway Iii

Electrical & Computer Engineering Theses & Dissertations

The feasibility of using reduced-order models and reduced-order observers with eigenvalue/eigenvector assignment procedures is investigated. A review of spectral assignment synthesis procedures is presented. Then, a reduced-order model which retains essential system characteristics is formulated. A constant state feedback matrix which assigns desired closed loop eigenvalues and approximates specified closed loop eigenvectors is calculated for the reduced-order model. It is shown that the eigenvalue and eigenvector assignments made in the reduced order system are retained when the feedback matrix is implemented about the full order system. In addition, those modes and associated eigenvectors which are not included in the reduced-order …

A Plasma Focus Interrupting Switch, Gregory Francis Knapp

Electrical & Computer Engineering Theses & Dissertations

The feasibility of using a dense plasma focus (DPF) as a current interrupting device has been investigated. Specifically, a 34-kJ, Mather-type DPF was modified to accept a third electrode so that a discharge could be created between this electrode and the center electrode of the DPF by a 10-kJ inductive energy storage circuit. It was anticipated that the accelerating mechanisms of the DPF pinch, which are known to cause a rapid reduction in the DPF current, would interrupt the 1-kA to 10-kA secondary discharge current thus forcing the secondary current through an external load and hence result in power amplification. …

Assessment Of The Accuracy Of Metal Cutting In A Microcomputer Controlled Machine, Aly Mohamed Saad Ed-Din Dars

Archived Theses and Dissertations

No abstract provided.

Design Of A Combustion System Simulating Waste Heat Recovery From Diesel Engine Exhaust Gases, Nikolaos Papadopoulos

Mechanical & Aerospace Engineering Theses & Dissertations

A forced-draft laboratory combustion system simulating diesel engine exhaust gas volume flow rate and temperature conditions for waste energy recovery is analyzed and discussed. The system consists of a fan which supplies the air. The slightly compressed air is then ducted through a combustor where it is heated, and then to an air-quencher where it is cooled to a desired temperature. Finally, the air is sent through a heat exchanger, after a diffuser process, for waste heat recovery.

A gas dynamic analysis has been performed for each component part as well as a parametric study via a computer program in …

Application Of An Optimization Technique To The Chattanooga Area Regional Transportation Authority (Carta) Bus System, Fernando R. Chacon

Masters Theses and Doctoral Dissertations

The purpose of this project is to apply a mathematical model and optimization techniqu,e to the Chattanooga Area Regional Transportation Authority (CARTA).A survey of recent urban tranaportation models was completed and the model demand most specific and applicable was chosen.A computer technique of sensitivity analysis was used in order to complete the model . A comparison of the analytical results with the current bus system was made. The results obtained in this project provide a framework in which CARTA may plan for more efficient operations.

An Inquiry Into Engineering Career Choice And Career Satisfaction, Gunars Bachs

Theses

The purpose of this thesis was to ascertain factors that motivate a person to study engineering, and to examine the aspects of engineering career satisfaction. This study was conducted as a survey by means of a mail questionnaire, which was distributed among graduates of New Jersey Institute of Technology. Another sample, comprised of master's degree recipients of NJIT who had received their bachelor's degree from other undergraduate schools, served as a control group.

Motivation factors and positive and negative aspects of the engineering career were established and ranked in order of their importance. A method to measure career satisfaction was …

Analysis Of Deflection Temperature Under Load, Anand M. Jagani

Theses

Deflection Temperature Under Load (DTUL) is an experimental value commonly used by designers to characterize a plastic in a high temperature environment. This value is currently measured by a standard test procedure specified by the ASTM D-648. A theoretical analysis of this test was made and computer programs were developed to calculate the Deflection Temperaure of Plastics Under Load based upon temperature dependent flexural modulus data and temperature dependent thermal properties of the plastics of interest. The results obtained from the theoretical analysis agree closely with the experimental values found in the literature for two resins. An analysis of the …

Processing Of Thin Film Devices, Ramzi Delpak

Retrospective Theses and Dissertations

The ability to do thin film processing has been established at UCF. This paper describes the facilities available. RF and DC sputtering was used for material deposition. The parameters for both were established experimentally, and the results are presented. Resistor and capacitor test patterns were used to test the accuracy of the system. The devices were fabricated and tested; experimental results are discussed.

Stormwater Detention Systems With Effluent Filtration, Linda M. Van De Graaff

Retrospective Theses and Dissertations

The growing concern for water quality enhancement of our surface waters has led to changes in detention facility design. Providing a filter media for the effluent water to travel through before discharge into the environment has become an area of interest. Thus, detention facilities may be used for both water quality and quantity control. Different soil medias were studied for the potential of pollutant removal and infiltration rates usable in design work. Both laboratory and field experimentation were performed. A computer program was also developed to model stormwater movement through a swale detention system. This research was performed to examine …

Display To Camera Calibration Techniques, Philip Gatt

Retrospective Theses and Dissertations

In today's technology, with digitally controlled optic sensing devices, there exists a need for a fast and accurate calibration procedure. Typical display devices and optic fiber bundles are plagued with inaccuracies. There are many sources of error such as delay, time constants, pixel distortion, pixel bleeding, and noise. The calibration procedure must measure these inaccuracies, and compute a set of correction factors. These correction factors are then used in real time to alter the command data, such that the intended pixels are correctly commanded. This paper discusses a calibration procedure, which employs a special matrix inverse algorithm. This algorithm, which …

Non-Iterative Finite Impulse Response Design Techniques, Carlton D. Bishop

Retrospective Theses and Dissertations

A general, non-iterative design technique for low shapefactor, transversal filters is presented. This design approach uses two cosine series to specify appropriate eigenfunctions. An infinite set of such eigenfunctions are defined and the method for choosing the coefficients is discussed.

The total filter response is specified as the product of two individual frequency responses. The impulse response of each is then determined by applying the superposition of appropriate eigenfunctions. The criteria for choosing the appropriate eigenfunctions is discussed.

A synthesis procedure for designing surface acoustic wave filters is presented. The effects of truncating the impulse response are also explored. A …

The Frequency Response Computation Of H(Z) Models That Include Digital Error Effects, Carol R. Smith

Retrospective Theses and Dissertations

Pulse responses are not suitable for evaluating H(z) frequency responses that include digital errors. Digital error effects, however, are conveniently included in H(z) frequency response calculations based on the step response. A non-real time algorithm for computing the frequency response of a real time digital filters based on the filter step response is developed and verified through an example.

Wastewater Characterization And Treatability For Aneastern Coal Slurry, Mark J. Flint

Retrospective Theses and Dissertations

A complete wastewater characterization study was performed on an eastern Kentucky coal slurry after a 10-day circulation period in a 40 foot (12.2 m) pilot-scale pipeline. The resulting wastewater was settled and decanted for additional lime and alum treatability studies. Easter coal slurries were characterized by high TDS, conductivity, sulfates and iron. Significant concentrations of a number of trace metals were also found; however, organics were very low. Wastewater quality varied considerably among several experiments and was presumed to be influenced by different properties of the coal and the addition of a corrosion inhibitor. The major treatment concern was removal …

A 'User-Friendly' Robot Operator Training Aid, Donald A. Washburn

Retrospective Theses and Dissertations

There will be an increasing demand for robot operators, since more companies are using robots in production and material handling. In order to train these would-be operators, a 'user-friendly' robot operator training aid was developed. This aid helps the trainee learn how to program a robot using on-line programming, and the trainee also obtains valuable hands-on experience. Since this training aid is user-friendly and has safety features, it requires little or no previous experience with robots or computers and minimal supervision. With this training, the would-be operators will acquire a basic understanding of how they can apply this experience to …

Gain Control Of A Time-Varying Signal Using A Multiplaying Dac, Yassin Movassaghi

Retrospective Theses and Dissertations

The design of a high speed circuit accepting a bipolar analog signal with a 3 db bandwidth of 20 MHZ and an eight bit unipolar gain control signal is presented in this thesis. The system produces the product of these two signals at a rate of one digital byte every 25 nsec. At the heart of the system are two multiplying digital to analog converters (DACs) operating in parallel. The circuit design was based on a statistically validated model for a multiplying DAC. This circuit could be used for controlling the intensity of each picture element (i.e. pixel) for many …