Engineering Commons^™

A Study Of The Permeability Of Clays Subjected To Organic And Inorganic Permeants, Janardanan O. Uppot

Doctoral Dissertations

"Two types of clays, a magnesium montrnorillonite and a kaolinite, were subjected to precise permeability tests in specially designed triaxial permeameters, using organic and inorgani c permeants, to study the changes in permeability due to the reaction between clays and permeants. The organic permeants were an acid (acetic acid), a base (aniline), a neutral polar fluid (methanol), a neutral nonpolar fluid (xylene), as well as EDTA and its sodium salt. The inorganic permeants were aqueous solutions of aluminum, magnesium, sodium, calcium, barium and strontium.

The clay samples were prepared by consolidating from slurry; they were subjected to back-pressure saturation and …

Radiation Damage To Gaas Solar Cells Including Isotropic Effects, Larry Victor Stock

Physics Theses & Dissertations

A model is developed for the short circuit current of a GaAs solar cell due to radiation (proton or electron) induced defects in the crystal structure. This model is verified by a comparison with proton and electron irradiation results. For electron radiation and energetic protons (energy> 10 MeV), it is found that the damage in the crystal is independent of the angle of incidence. On the other hand, for lower energy proton radiation, the damage as a function of cell thickness is highly dependent on incident angle and energy. The cell's response to low energy protons is strongly dependent on …

Decentralized Optimal Control With Application To Dynamic Routing In Computer Communication Networks, Ning Wang

Dissertations

This research considers the dynamic routing problem of computer communication networks in the framework of decentralized control theory. The routing dynamics are modeled in terms of a state equation with multiple controllers. Routing, or control of message flow, is formulated as an optimal control problem with multiple decision makers. Each decision maker may have access to different set of information and work cooperatively to optimize a common system performance index.

Necessary and sufficient conditions for optimality are derived for a system with a deterministic and a stochastic traffic patterns under a linear information structure and a quadratic performance index. The …

Stochastic Estimation Applied To The Land Speed Of Sound Record Attempt By A Rocket Car, David A. Reinholz

Theses and Dissertations

Optimal linear smoothing theory is applied to the data from the Speed of Sound record attempt of a three-wheeled rocket car on 17 December 1979. A forward-backward estimation method is used which employs a seven state forward-running extended Kalman filter and a Meditch-form backward recursive 'fixed-interval' smoothing algorithm. Data for this analysis is supplied by a longitudinal accelerometer mounted on the vehicle and tracking radar measurements of range, azimuth, and elevation. States of interest include two components of vehicle position and velocity, accelerometer time-correlated error, and radar range and azimuth bias errors. Two iterations of the forward-backward smoothing algorithm provide …

Two-Dimensional Computer Modeling Of Joints And Fractures In Continua, Royd R. Nelson

Theses and Dissertations

This thesis presents a numerical formulation which incorporates the effects of joints, cracks, and fractures into a mathematical mode used to in an existing finite element code. Two separate crack definitions were incorporated, one involving a discrete crack model, and the other a continuum approach defining a new material with regularly spaced joints. Several examples are also presented demonstrating the use of this capability.

Effect Of Refrigerant Charge And Condenser Temperature On The Operating Characteristics Of A Vapor-Compression Air Conditioning System, Ezzat Fikri Assaad

Archived Theses and Dissertations

No abstract provided.

Mathematical Models Of Unsteady Operation Of A Packed Column, Jen-Fu Chao

Dissertations

Analytical solutions of differential equations applicable to extraction, ion exchange, or adsorption processes in packed beds are presented. Results are given for three different cases. The first case accounts for adsorption phenomena only. The second one includes surface adsorption on particles and the effects of longitudinal dispersion in the bed. The third one deals with diffusion in particles and longitudinal dispersion in the bed. In the mathematical modelling of these three cases, a linear equilibrium relationship between the solute in the liquid phase and solute in the solid phase is used. The first case is solved using the single boundary …

The Settling Of An Arbitrary Number Of Spherical Particles Arranged On The Corners Of A Regular Polygon In A Viscous Fluid, Eric Robert Bixon

Dissertations

The creeping motion equation has been solved for the case of planar arrays of spheres settling under the influence of gravity in a viscous fluid. The solution is a general solution which applies to an arbitrary number of spheres. All particles will lie at the corners of a regular polygon. Thus, two particles side by side, three particles in an equilateral triangular array, or four spheres in a square array will be special cases of the general solution.

The solution has been obtained by a unique application of the method of reflections. Only a first correction to the drag has …

Measurement Of Thermal Conductivity Of Polymers Using Line Source Method, Manojkumar C. Patel

Theses

The purpose of this investigation was to evaluate the Line Source technique to measure the thermal conductivity of different molten polymers. Although the results obtained using this method are within acceptable experimental error limits, due to tec reasons explained, the results are not as accurate as claimed in the literature which describe this technique.

High Speed Puncture Impact Studies Of Structural Foam Plaques, Shashi B. Kumar

Theses

The constant velocity high speed impact study was conducted on different thermoplastic and thermoset structural foam plaques to study their impact behavior. Plaques of Noryl, Polycarbonate, Polystyrene and Polyurethane were carefully chosen to represent a true sample of the manufactured product. Test plaques were marked such that specimens could be tested for variation in location, thickness of the plaque and variation between plaques. High speed puncture impact experiment was conducted on each specimen and the results were analysed.

The test results showed that the impact performance varied significantly over the plaque. Noryl and Polycarbonate did not exhibit any correlation for …

Behavior Of Joints Using Reinforced Polymer Concrete Under Seismic Loading, Ishac H. Kafrouni

Theses

This report describes the analysis and testing of two types of exterior beam-column joints conducted at New Jersey Institute of Technology. The testing program consisted of six beam column joints with varying strength cementing agents in the joint region: normal, high strength and polymer concrete. Half of the specimens contained 1.5 percent by volume of hooked end fibers. The study of the behavior of these beam column joints has indicated 2 cases of failures: a critical region in which the inelastic behavior was controlled by bending and, a critical region in which the inelastic behavior was controlled by high shear. …

Design Of A Photoreactor For The Oxidation Of Toxic Pollutants In Water By Ozone And Ultraviolet Radiation, Shahab Rashid Khan

Theses

A photoreactor has been designed to oxidize refractory chemicals found in water using ozone and ultraviolet radiation. The feasibility of the ozone/UV process has been examined by conducting experiments with three model compounds, namely, (1) o-chlorophenol (2) m-chlorophenol and (3) p-chloro phenol. For o-chlorophenol and p-chloro-phenol, reactions were very fast with ozone/UV oxidation and somewhat slower with m-chlorophenol. It is concluded that UV irradiation increases the decomposition of ozone and the resulting unstable intermediates are much more reactive than ozone. Ultraviolet light also helps in decomposing the substrate molecules. The effect of UV upon decomposition of ozone is more pronounced …

An Interactive Procedure For Numerical Design Optimization, Jaehwan Lee

Theses

An interactive version of the numerical design optimization method of Pappas for the solution of nonlinear optimization problems is presented in this thesis, A designer intervention strategy is employed herein for interactive optimization to allow the designer to control and manage the optimization process. This procedure embodied in the interactive CADOP6 program is tested on the ten bench mark problems of Eason and Fenton to illustrate the designer intervented optimization process and to provide a comparison with the fully automated procedure of Pappas This designer intervented interactive program appears more effective and faster than the completely automated CADOP5 code on …

Spectral Analysis Of Brainstem Auditory Evoked Responses, Amir Hossein Massumkhani

Theses

In this study, the power spectrum density of the brainstem auditory evoked responses is estimated by the method of periodogram. Several techniques for reducing the leakage due to the finite length of data, smoothing the spectrum and reducing the ambiguity in the spectrum due to the resolution are studied. It is shown that a Hamming window reduces the leakage considerably and zero extention of the data to 512 points produces sufficient spectrum bandwidth. Three major peaks are observed at 100, 500, and 1000 Hz which are stable for different evoked responses. In one case with a delayed wave V, the …

The Fundamental Hardware Elements And Options Of Digital Signal Processing, Mark A. Hemmerlein

Retrospective Theses and Dissertations

The hardware available for digital signal processing is evaluated. The elements required for implementation of digital signal processing applications are identified. These elements--memories, ALUs and multipliers -- are analyzed. Then the operation of parts which make up a range of possible solutions are evaluated. Thus, the graduating engineer is aided in making a transition from the theoretical to the practical world.

Digital Filtering With The Iapx 86/20, Robert E. Canright

Retrospective Theses and Dissertations

The iAPX 86/20 (8086 with the 8087 numeric coprocessor) is considered for digital filtering. The advantage in using the iAPX 86/20 lies in the 80-bit width of the 8087 floating-point arithmetic-registers. With such large arithmetic registers, the effects of coefficient roundoff and arithmetic roundoff errors on the filter output are reduced. The price paid for the improved numerical performance is the increased time spent by the system moving data to and from memory. The method of Knowles and Olcayto for measuring the effect of coefficient roundoff is studies in detail. This method is applied to an example filter in order …

Design Of A Single User Deconcentrator For A Conferenced Voice Communication Circuit Switching System, Ming-Yung Wen

Retrospective Theses and Dissertations

A single user deconcentrator is designed for a circuit switched digital switching system which emphasizes mass conferencing. The switching system consists of distributed concentrators which include a first level of conferencing and a broadcast bus which includes a second level of conferencing. The deconcentrator features volume adjustment of individual conferences as well as a third and last level of conferencing- a conference of the individual conferences obtained from the broadcast bus. The design identifies the MSI and SSI components of the deconcentrator and provides an estimate of timing and board size. An alternative volume adjustment algorithm and the extension of …

Models For Economic Evaluation Of Flexible Manufacturing Systems, Daniel P. Salomon

Retrospective Theses and Dissertations

The current methods of economic justification are not suitable for identifying the benefits of automated manufacturing systems. This study is an introduction to Flexible Manufacturing Systems (FMS), its main features, and the economic benefits that can be expected. The models are designed to perform the following analyses: 1. Analysis of direct cost savings. 2. Analysis of the impact of incremental implementation on capital recovery costs. 3. Analysis of the cost effects of improving machine utilization and reducing manufacturing lead time. 4. Sensitivity analysis of the after-tax equivalent uniform annual cost of a FMS and a conventional system. The models are …

Testing Of Active Feedback Applied To Piezoelectric Devices, William H. Barrow

Retrospective Theses and Dissertations

The purpose of this research is to test a unique implementation of active feedback applied to a low frequency piezoelectric transducer. Understanding that active feedback can be used to shape the frequency response of an electrical system a method for applying active electroacoustical feedback will be used to obtain a wider acoustical bandwidth in a piezoelectric transmitter. By applying active feedback to a resonant device its bandwidth was increased by a factor of 2.5. This is a significant improvement for applications where minimum electrical phase shift versus frequency is desired.

On The Theory And Experimental Results Of A Sensitive Fiber Optic Laser Accelerometer, Steven C. Furlong

Retrospective Theses and Dissertations

No abstract provided.

Application Of Ground Penetrating Radar To The Detection Of Subsurface Cavities, Gary L. Kuhns

Retrospective Theses and Dissertations

Ground Penetrating Radar (GPR) identifies subsurface features by distinguishing materials with different dielectric constants and electrical conductivities. Subsurface cavities can, therefore, be detected by the variation in their electrical properties from the electrical properties of the surrounding material. To test the cavity detection ability of GPR, subsurface cavities of varying size, shape and content were modeled. Radar response to the cavity models was found to be affected by the composition of the surrounding soil material, the depth of the groundwater table, and the radar signal frequency. Based on knowledge gained from the cavity modeling study, a natural subsurface cavity was …

Experiments On Melting Around An Isothermal Horizontal Cylinder Under Computer Control, Timothy Moore Rothgeb

Mechanical & Aerospace Engineering Theses & Dissertations

The melting of a solid around an isothermal horizontal cylinder is a physical phenomenon which must be understood when attempting to design a latent heat storage system. The desire to design such a system is the motivating factor in this research. To gain this understanding of the fundamental melting processes several experiments were designed, and two sets of Stefan and Rayleigh number experiments were undertaken. Experiments were also performed to determine the properties of the paraffin that was used in these investigations. During the investigations of the melting processes, the temperature was measured at several locations throughout the liquid and …

Design Of Efficient Algorithms Through Minimization Of Data Transfers, Yong Mo Chong

Electrical & Computer Engineering Theses & Dissertations

This thesis explores the time optimal implementation of computational graphs on a finite register machine. The implementation fully exploits the machine architecture, especially, the number of registers. The derived algorithms allow one to obtain time efficient implementations of a given graph in machines with a known number of registers.

These optimization procedures are applied to digital signal processing graphs. It is shown that the regular structure of these graphs allows one to identify computational kernels which, when used repeatedly, can cover the entire graph. The l- and r-register implementations of Hadamard and Fast Fourier Transforms using various computational kernels are …

Circuit Analysis Of A Gas Flow Switch, Teri Marie Owens

Electrical & Computer Engineering Theses & Dissertations

The circuit analysis of a gas flow switch is presented. The objective of the analysis is to model the switching process during spark gap breakdown. This information is useful in understanding switch operation and identifying ways to improve switch performance.

A lumped circuit model is used to describe a gas flow switch during the switching process. Certain circuit element values are determined experimentally through static tests. Other component values, including a time-varying switch resistance and inductance, are estimated from current measurements. In particular, unknown constants in expressions for gap resistance and inductance are determined using an iterative parameter estimation technique. …

Data Acquisition And Parameter Identification In Electro-Oculography, Wolfgang Poelzleitner

Theses

Electro-Oculography (EOG) is used in clinical ophthalmology to measure the time response of the corneoretinal potential (CRP) to changes in light intensity. An automatized data acquisition and system modeling link has been developed that significantly reduces processing time presently required for EOG. The data acquisition is performed on a microprocessor based instrument, which supervises the EOG-test, measures the potential and, after completion of the test, transfers the results to a mainframe computer. Parameter identification routines provide graphical representation and mathematical models for the CRP. Both nonlinear curve fitting methods and Least Squares System Identification schemes are used.

The Lewis-Matheson Method On Computer, William Raymond Castner

Theses

Lewis and Matheson, in the early 1930's, developed a manual calculation technique for the solution of multicomponent distillation problems. The object of this study was to see if there would be any advantage to using the Lewis-Matheson method, once incorporated onto a computer, over current multicomponent distillation solution techniques. The immediate advantage of using the L-M technique is that it requires fewer preliminary calculations than other computer methods. It was found that the L-M technique uses about half the execution time of a typical Newton-Raphson program, while using only one tenth the computer core (memory). This was not intended to …

Deposition Of Particles In Horozontal Parallel Plate Channel Due To Image Charge, Inertia, Viscosity And Gravity, Chi-Young Chu

Theses

This investigation was made to determine the effect on the deposition of particle in a horizontal parallel-plate channel due to the influences of image charge, viscosity, inertia and gravity. The flow considered was lamina, incompressible and steady. The flow patterns considered were uniform and fully developed with symmetry about the axis of the channel.

The governing equations derived for a particle were based on Newton's Second Law of motion. Since the resulting governing equations are linear second order differential equations, Runge-Kutta algorithm is used to solve the problem and graphical techniques is used to interpret the results of the numerical …

Preparation And Characterization Of Blocked Diisocyanate Monomers For Dental Applications, Stephen Richard Angeli

Theses

Six new monomers were prepared and characterized. The six monomers are blocked diisocyanate compounds. In the preparation 2,4-tolylene diisocyanate was first blocked with 2=hydroxyethyl methacrylate in the para NCO position. Six different blocking agents were then used to block the ortho NCO in the preparation of the monomers: (1) p-methoxyphenol, (2) m-methoxyphenol, (3) o-methoxyphenol, (4) p-chlorophenol, (5) m-chlorophenol, and (6) o-chlorophenol. The six monomers were characterized by mp, liquid chromatography, IR, NMR, and elemental analysis. All the characterizations show that the monomers are indeed the desired products.

Experimental Investigation Of An Axisymmetric Air Jet Impinging On A Flat Plate, Saibal Basu

Theses

Experimental investigation was carried out on a circular, submerged, axisymmetric turbulent air jet-with normal impingement on a smooth, flat, square lucite plate, The flow was considered to be incompressible because the velocity of the jet was not too high, with Mach Number of the order of 0.3. Three nozzle diameters of 0.375" (9,525 mm), 0.250" (6.35 mm) and 0.125" (3.175 mm) were used with Reynolds number ranging from 7,000 to 70,000.

Various flow parameters were measured to obtain the velocity and pressure distributions at the surface of the flat lucite plate and along the centerline of the normal impinging air …

The Quasisteady Approach For Thermal Analysis Of Frost Action Below Refrigerated Warehouses, Milan Kumar Bag

Theses

The quasisteady method of analysis has been used to determine the frost depth below refrigerated warehouses. For the case when the ground temperature is different from phase change temperature, the solution is obtained by numerical integration of the equation governing the phase change process. When the ground temperature approaches the phase change temperature closed form solution is obtained. The results obtained from the quasisteady method compare well with the experimental results. The results presented in this thesis should find use in the design of the refrigerated warehouses in the colder regions of the world.