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Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 15, Number 1, January 1999, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

An eight page newsletter created by the Wright State University College of Engineering and Computer Science that addresses the current affairs of the college.

Numerical Simulation And Experimental Verification Of Cone Penetration Rate And Anisotropy In Cohesive Soils., Daekyu Kim

LSU Historical Dissertations and Theses

This research focuses on the effects of cone penetration rate and anisotropy on the results of piezocone penetration and subsequent dissipation tests. Finite element analyses, and miniature piezocone penetration and dissipation tests in a calibration chamber were performed, then the results were compared. The anisotropic elastoplastic-viscoplastic; bounding surface model was chosen as a soil model and it was implemented into a computer program, ANCALBR8. The isotropic/anisotropic triaxial compression, creep tests, and oedometer tests were performed to determine the model parameter values and verify the model. The model showed very good agreement with the triaxial test results. The theoretical formulation was …

Analysis Of Non-Linear Formation Fracture Resistance Tests Obtained During Oil Well Drilling Operations., Gursat Altun

LSU Historical Dissertations and Theses

A leak-off test (LOT), commonly known as formation pressure integrity test (PIT), is a verification method to estimate the fracture pressure of exposed formations. After cementing each casing string, a LOT is run to verify that the casing, cement, and formation below the casing seat can withstand the wellbore pressure required to drill safely to the next casing setting depth. Fracture pressure determined from the test is used as the maximum pressure that may be imposed on that formation. Critical drilling decisions for mud weights, casing setting depths, and well control techniques are based upon the result of a LOT. …

Metals Release From Freshwater And Estuarine Sediments In Thin-Disk Leaching Columns., Tommy Eldridge Myers

LSU Historical Dissertations and Theses

Column leaching tests were conducted on two freshwater sediments and two estuarine sediments. Leachate samples were analyzed for total organic carbon (TOC), cadmium, chromium, copper, iron, manganese, lead, nickel, and zinc. Metal and TOC elution curves for freshwater sediments were fundamentally different from estuarine sediment elution curves. The difference was due to colloid-facilitated transport of metals and TOC in estuarine sediments that was caused by salt washout during leaching with distilled-deionized water. Metals and TOC concentrations in freshwater sediment leachates tended to monotonically decrease from initial pore water concentrations. Leaching of metals and TOC from freshwater sediments was modeled with …

Parameter Estimation For The Finite Fourier Distribution In Civil Engineering Application., Ching-Nien Tsai

LSU Historical Dissertations and Theses

A solution to a one dimensional diffusion equation applicable to a finite interval was adapted to be a probability distribution function. This distribution function can accommodate various shapes of distribution such as those similar to the uniform, single-modal, and bi-modal distributions. This distribution is bounded at both boundaries. It was named the finite Fourier distribution (FFD) to recognize the form of the distribution. The FFD was extended to include a linear combination of the FFD termed two-component FFD. Monte Carlo simulation technique was used to evaluate four parameter estimation techniques, Method of Maximum Likelihood Estimator (MLE), Method of Moments (MOM), …

Integrative Approach To Online Quality Management: Process Control And Packout Verification In An Intelligent Manufacturing Workcell., Turuvekere R. Sethumadhava

LSU Historical Dissertations and Theses

The current global competition and the economic situation in the United States and the world is forcing industries to produce quality products quickly and at a competitive price. Many industries are aiming towards world class manufacturing objectives like responsive delivery, defect free product and declining cost. Industries in the present environment can survive and produce the quality products to customer expectations only if they implement new technologies. The key element in the success of industries is using the continuous process improvement strategies like reducing process variability and reducing response time to process deviations. Achieving quality in manufacturing processes is an …

An Engineering Equation Of State: Square-Well Statistical Associating Fluid Theory (Saft)., Hertanto Adidharma

LSU Historical Dissertations and Theses

Molecular thermodynamics is an engineering discipline rooted in molecular physics and physical chemistry and aimed at developing practical models that predict the properties of matter. The goal of this work is to develop a molecular thermodynamic model for predicting fluid densities, phase equilibria, and energy functions, such as enthalpy and heat capacity. Chemical engineers need these properties to develop and design new processes and materials, and to make these processes energy efficient and environmentally benign. The approach is to hypothesize a mathematical approximation that captures interactions among real molecules on the basis of a molecular theory called the statistical associating …

Flexural Creep Analysis Of Recycled Polymeric Structural Elements., Jose Noe Martinez-Guerrero

LSU Historical Dissertations and Theses

A structural product made of recycled plastics in standard sections similar to dimensional lumber is referred to as plastic lumber. The recycled plastics used in the manufacture of these members include high density polyethylene, polyethylene terephthalate and polystyrene. Plastic lumber is a viscoelastic material possessing mechanical properties that are time and temperature dependent. This structural product is currently used primarily in non-load-bearing and low-end structural applications because of the non availability of engineering data and concerns about its creep behavior. Creep, which is the time dependent deformation under constant stress, is high for plastic lumber and is temperature sensitive. A …

Computational Approach For Determination Of The Hydraulic Conductivity Of Soils Using Continuous Intrusion Piezocone Penetration Test., Chung Rak Song

LSU Historical Dissertations and Theses

In order to obtain the hydraulic conductivity or the coefficient of consolidation of the soil from PCPT, the pore pressure response during dissipation test is typically used. This method, however, requires the intermittent stopping of the advancement of the piezocone penetrometer for the dissipation test. Also, this method does not fully take into account the pore pressure interaction between near and far fields as pointed out by previous researchers (Kurup and Tumay, 1997). Thus a new rational approach is investigated here. The proposed method utilizes the pore water pressure during the penetration of the piezocone penetrometer. By its nature, the …

Topics In Chaotic Secure Communication, Andrew Thomas Parker

Doctoral Dissertations

Results in nonlinear dynamics and chaos during this decade have been applied to problems in secure communications with limited success. Most of these applications have been based on the chaotic synchronization property discovered by Pecora and Carroll in 1989 [37]. Short [44, 45, 48] demonstrated the effectiveness of nonlinear dynamic (NLD) forecasting methods in breaking this class of communication schemes. In response, investigators have proposed enhancements to the basic synchronization technique in an attempt to improve the security properties. In this work two of these newer communication systems will be analyzed using NLD forecasting and other techniques to determine the …

Hardware-Software Codesign In A High-Level Synthesis Environment, Tamas L. Visegrady

Doctoral Dissertations

Interfacing hardware-oriented high-level synthesis to software development is a computationally hard problem for which no general solution exists. Under special conditions, the hardware-software codesign (system-level synthesis) problem may be analyzed with traditional tools and efficient heuristics. This dissertation introduces a new alternative to the currently used heuristic methods. The new approach combines the results of top-down hardware development with existing basic hardware units (bottom-up libraries) and compiler generation tools. The optimization goal is to maximize operating frequency or minimize cost with reasonable tradeoffs in other properties.

The dissertation research provides a unified approach to hardware-software codesign. The improvements over previously …

Instantaneous Learning Neural Networks., Kun Won Tang

LSU Historical Dissertations and Theses

Instantaneous learning is a desirable feature in neural networks. This type of learning enables the network to be trained very quickly, typically in just one or two passes of the training set as opposed to hundreds or even thousands of passes for networks trained by an iterative process, such as the error backpropagation (BP) algorithm. This dissertation first reviews several existing types of neural networks with instantaneous learning capability. It then proposes a new network called the Fuzzy Classification (FC) Neural Network that can be trained with two passes of the training samples. The first pass assigns the synaptic weights …

Machine -Cell Location Problems For Multiproduct Flowlines., Junfang Yu

LSU Historical Dissertations and Theses

Jobs (parts) and machines are usually grouped into part-families and machine-cells in a flexible, cellular manufacturing system to minimize the flows of all work-in-processes (WIP). As a result of this grouping, some parts may need processing on some machines that are not in their own cells. The parts requiring machines in other cells are called 'exceptional parts,' and the corresponding machines are called ' bottleneck machines.' Usually, there are two ways to deal with this inter-cell flow problem: using a material handling system to move the exceptional parts among the cells or duplicating the bottleneck machine(s) for the corresponding exceptional …

Pine-Polyethylene (Wood -Polymer) Composites: Synthesis And Mechanical Behavior Characterization., Parviz S. Razi

LSU Historical Dissertations and Theses

Processing of recycled wood chips, recently produced after extraction of creosote from telephone posts and railroad crossties, and combining them with a recycled polymer for the synthesis of novel composite materials would initiate a new trend toward preservation of natural resources. The challenge is taken in this work to produce and study the properties of such materials for further advancement of science. In the present study, addition of pine wood chips to HDPE reduced the tensile strength and break strain in tensile loading. Smaller wood chips generally resulted in smaller reductions. Peak load, modulus of rupture and stiffness were slightly …

Design Of Work-Rest Schedules For Vdt Operators., Rana Balci

LSU Historical Dissertations and Theses

The number of musculoskeletal and psychological discomforts is increasing as a result of continuing growth of VDT work. Although ergonomic improvements in workstation design can be applied, an effective work-rest schedule is an economical way to reduce these problems. The objective of this research was to determine an effective work-rest schedule for VDT operators. In addition to a discomfort questionnaire, performance and electromyography measurements from trapezius and flexor carpi radialis were used. Three different work-rest schedules were applied: 60-minute work/10-minute rest, 30-minute work/5-minute rest, and for the third schedule, the subjects received four breaks from VDT work each hour additional …

Scaling Simulations Of Reconfigurable Meshes., Jose Alberto Fernandez Zepeda

LSU Historical Dissertations and Theses

This dissertation deals with reconfigurable bus-based models, a new type of parallel machine that uses dynamically alterable connections between processors to allow efficient communication and to perform fast computations. We focus this work on the Reconfigurable Mesh (R-Mesh), one of the most widely studied reconfigurable models. We study the ability of the R-Mesh to adapt an algorithm instance of an arbitrary size to run on a given smaller model size without significant loss of efficiency. A scaling simulation achieves this adaptation, and the simulation overhead expresses the efficiency of the simulation. We construct a scaling simulation for the Fusing-Restricted Reconfigurable …

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 14, Number 9, December 1998, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

An eight page newsletter created by the Wright State University College of Engineering and Computer Science that addresses the current affairs of the college.

Robust Course-Boundary Extraction Algorithms For Autonomous Vehicles, Chris Roman, Charles Reinholtz

Graduate School of Oceanography Faculty Publications

Practical autonomous robotic vehicles require dependable methods for accurately identifying course or roadway boundaries. The authors have developed a method to reliably extract the boundary line using simple dynamic thresholding, noise filtering, and blob removal. This article describes their efforts to apply this procedure in developing an autonomous vehicle.

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 14, Number 8, October 1998, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

An eight page newsletter created by the Wright State University College of Engineering and Computer Science that addresses the current affairs of the college.

Construction Of Some Combinatorial Designs Arising Out Of Statistical Experiments., Tridib Kumar Dutta Dr.

Doctoral Theses

Chis dissertation considers construction of two kinds of combi natorial sesigns as used by statisticians: repeated measurements designs (RMDS) and symmetric balanced squares (SBSS). 1.1. REPEATED MEASUREMENTS DESIGNS The researchers need to perform experiments where each experimental unit receives some or all of the treatments in an appropriate sequence over a number of successive periods. These designs are known by several names in the statistical 1iterature: repeated measurements designs, crossover or changeover designs, (multiple) time series designs, and before-after designs. If there are n experimental units 1,2, ... n, t treatments and p periods 0,1, .. .p-1, applied, then an …

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 14, Number 7, September 1998, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

An eight page newsletter created by the Wright State University College of Engineering and Computer Science that addresses the current affairs of the college.

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 14, Number 6, June 1998, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

A ten page newsletter created by the Wright State University College of Engineering and Computer Science that addresses the current affairs of the college.

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 14, Number 5, May 1998, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

A ten page newsletter created by the Wright State University College of Engineering and Computer Science that addresses the current affairs of the college.

Impedance Of A Dipole Antenna In Ionospheric Plasma, Pavel Nikitin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Different approaches to evaluating the behavior of the impedance of an electrically short dipole antenna in the ionosphere as a function of the driving frequency are discussed. The induced EMF method in quasi-static approximation is chosen for evaluating the impedance and explained in great detail. The E-region of the ionosphere is considered and the cold collisional plasma model is used.

The influence of a density gradient in plasma on the impedance is explored, and the possible current distributions on the surface of the antenna are considered, including the current distribution for the antenna with a gap. The conclusions are drawn …

Dual Adaptive Recumbent Trike, Jason V. Eastman

Undergraduate Honors Capstone Projects

The DART team's objective was to develop a tandem recumbent tricycle that would be economical, easy to build, and adaptable. This would involve designing, building and testing the tricycle.

Recruitment Of High School Minority Students Into Engineering, Math, Science And Technology Futures On Predominantly White Campuses, Franklin Titus Thompson, Tome Sires, Carol Batt

Teacher Education Faculty Proceedings & Presentations

“This session is for college administrators who wish to make traditionally elitist program more inclusive. Its is also helpful to community and school district personnel who wish to investigate how to set up a similar program in their community.”

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 14, Number 4, April 1998, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

An eight page newsletter created by the Wright State University College of Engineering and Computer Science that addresses the current affairs of the college.

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 14, Number 3, March 1998, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

An eight page newsletter created by the Wright State University College of Engineering and Computer Science that addresses the current affairs of the college.

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 14, Number 2, February 1998, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

A ten page newsletter created by the Wright State University College of Engineering and Computer Science that addresses the current affairs of the college.

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 14, Number 1, January 1998, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

A fourteen page newsletter created by the Wright State University College of Engineering and Computer Science that addresses the current affairs of the college.