Digital Commons Network^™

Spatial-Temporal Reasoning Applications Of Computational Intelligence In The Game Of Go And Computer Networks, Tae-Hyung Kim

Doctoral Dissertations

"Spatial-temporal reasoning is the ability to reason with spatial images or information about space over time. In this dissertation, computational intelligence techniques are applied to computer Go and computer network applications. Among four experiments, the first three are related to the game of Go, and the last one concerns the routing problem in computer networks.

The first experiment represents the first training of a modified cellular simultaneous recurrent network (CSRN) trained with cellular particle swarm optimization (PSO). Another contribution is the development of a comprehensive theoretical study of a 2x2 Go research platform with a certified 5 dan Go expert. …

Strategic Management And Entrepreneurship As Economic Development Tools, Norbert Ziemer

Doctoral Dissertations

This research develops a framework of Biobased Entrepreneurial Ventures for Rural Economic Development. Rural economic development poses unique challenges and opportunities, based on available production assets, workforce trends like "brain drain," and access to industry clusters. However, certain entrepreneurial venture opportunities are preferable for rural economic development. Since supply chains are vital to business success, initial emphasis is placed on the biomass resource base to be transformed through entrepreneurial activity into higher economic value outputs. The literature contains research on specific opportunities in rural economic development (e.g. ethanol, wind power). Many of these are limited in scope and depend on …

Sustainable Engineering Practices In Transportation Projects, Kiran Rangarajan

Doctoral Dissertations

"Sustainability has become an important issue in transportation and infrastructure development projects. While several agencies are trying to incorporate a range of sustainability measures in their goals and missions, only a few planning agencies have been able to implement these policies and they are far from perfect. The low rate of success in implementing sustainable policies is primarily due to incomplete understanding of the system and the interaction between various elements of the system. The conventional planning efforts focuses mainly on performance measures pertaining to the system and its impact on the environment but seldom on the social and economic …

Search-Based System Architecture Development Using A Holistic Modeling Approach, Renzhong Wang

Doctoral Dissertations

"This dissertation presents an innovative approach to system architecting where search algorithms are used to explore design trade space for good architecture alternatives. Such an approach is achieved by integrating certain model construction, alternative generation, simulation, and assessment processes into a coherent and automated framework. This framework is facilitated by a holistic modeling approach that combines the capabilities of Object Process Methodology (OPM), Colored Petri Net (CPN), and feature model. The resultant holistic model can not only capture the structural, behavioral, and dynamic aspects of a system, allowing simulation and strong analysis methods to be applied, it can also specify …

The Effect Of Supercritical Water On Crude Glycerin Solution, Jared Bouquet

Doctoral Dissertations

"Crude glycerin solution, a principal byproduct of the conventional biodiesel process, was reacted in supercritical water using a specially designed Haynesʼ Alloy 282 reactor system for the production of hydrogen rich syngas. The effects of temperature, pressure, water-to-carbon molar ratio, reactor residence time, and glycerin-to-methanol weight ratio on the extent of carbon gasification and gas composition were explored. Based on the results, the extent and selectivity of reactions that concurrently occur when methanol and glycerin are in the presence of supercritical water were analyzed. A decomposition reaction pathway for glycerin conversion to syngas was hypothesized, and then utilizing the results …

The Characterization Of Volatiles Associated With Young Stellar Objects, Kari Anne Wojtkowski

Doctoral Dissertations

In the first portion of this work, we searched for differences in volatiles within a single star forming region, Rho Ophiuchi. We determined the amount, temperature, and composition of two ice features, the bending modes of CO₂ and H₂O at 15 µm and 6 µm, respectively, toward 28 Young Stellar Objects (YSOs). We found that more than 50% of the YSOs studied contained a portion of crystalline CO₂ ice. We also found that some sources with Flat or borderline Class II Spectral Energy Distributions (SEDs) have a larger abundance of CO₂ ice with respect to H₂O ice. In addition to …

Manufacturing And Characterization Of Soy-Based Polyurethane Composites, Rama Bhadra Raju Vuppalapati

Doctoral Dissertations

"The major cost drivers for composites are raw materials and manufacturing process. Automated manufacturing processes like pultrusion and low cost bio-based raw materials can significantly lower the cost of composites. Polyurethane (PU) resin systems are being introduced in the pultrusion industry as they have higher performance characteristics and manufacturing feasibility when compared to conventional resin systems such as polyester and vinyl ester. PU resin systems are generally characterized as aromatic and aliphatic. Aliphatic PU has lower mechanical properties than the aromatic resin system due to its chemical structure. Nano materials can be used to increase the mechanical properties of aliphatic …

Hollow Hydroxyapatite Microspheres As Devices For Controlled Delivery Of Proteins And As Scaffolds For Tissue Engineering, Hailuo Fu

Doctoral Dissertations

"Hollow HA microspheres were prepared by converting Li₂O-CaO-B₂O₃ glass microspheres in a K₂HPO₄ solution. Process parameters, such as reaction temperature (25°C-60°C) and concentration of the phosphate solution (0.02-0.25 M) significantly influenced the microstructure of the hollow HA microspheres. Microspheres with the largest hollow core size were obtained at lower temperature or with low K₂HPO₄ concentration. In comparison, microspheres with high surface area (~140 m²/g) were obtained at higher K₂HPO₄ concentration (0.25 M). Upon heat treatment (up to 900°C), the surface area of the hollow HA microspheres decreased (from ~100 m²/g to ~2 m²/g), and the rupture strength increased (from ~11 …

Numerical Simulations Of Fracture Propagation And Sealing: Implications For Wellbore Strengthening, Saeed Salehi

Doctoral Dissertations

"To mitigate the small tolerance between pore pressure and fracture gradients an engineering practice referred to as "wellbore strengthening" is conducted to increase the fracture gradient. The method relies on propping and/or sealing the fractures with specially designed materials. Different competing theories exist for physical wellbore strengthening mechanisms which can be categorized into two groups. The first group explains that strengthening happens as a result of increasing wellbore hoop stress when fractures are sealed while the second group emphasis is on fracture tip isolation with suitable materials and enhancing fracture propagation pressure. The numerical models and lab experiments …

Part I: Quantitative Determination Of Total Corrosive Sulfur In Mineral Insulating Oils And Technical Liquids; Part Ii: Development And Validation Of A Broad Spectrum Microbial Disinfectant, Kyle Rodney Anderson

Doctoral Dissertations

"Part one of this dissertation deals with the development and validation of a test method for determination of total corrosive sulfur in mineral insulating oils other technical oils. The method involved reaction of corrosive sulfur compounds in oils with finely divided copper at temperatures ≥ 110 °C. The reaction yielded cuprous sulfide (Cu₂S), Cu₂S was then oxidized to cupric sulfate (CuSO₄), which was determined as sulfate with ion chromatography. The method offers a quantitative assessment of corrosive sulfur compounds in oils and eliminates ambiguities associated with the international standard methods for corrosive sulfur in mineral insulating oils and other technical …

Real-Time Supply Chain Predictive Metrics, William Scott Hunter

Doctoral Dissertations

"Supply chains drive the production world. Virtually all products use a supply chain to produce them and they can determine the success of companies using them. The ability to manage supply chains is currently a mix of relationship management and science, combining personal and company relationships with data analysis.

The increased dependency on supply chains has increased the need to develop and use predictive real-time metrics to manage supply chain risk, measure suppliers and drive performance. Current metrics used are reactive and stagnant in nature. Real-time metrics will allow supply chain professionals to better manage risk. Current management techniques include …

Real-Time Localization Using Received Signal Strength, Mohammed Rana Basheer

Doctoral Dissertations

"Locating and tracking assets in an indoor environment is a fundamental requirement for several applications which include for instance network enabled manufacturing. However, translating time of flight-based GPS technique for indoor solutions has proven very costly and inaccurate primarily due to the need for high resolution clocks and the non-availability of reliable line of sight condition between the transmitter and receiver. In this dissertation, localization and tracking of wireless devices using radio signal strength (RSS) measurements in an indoor environment is undertaken. This dissertation is presented in the form of five papers.

The first two papers deal with localization and …

Modeling And Synthesis Of Pvdf-Based Dielectrics For Energy Storage Applications, Xuhui Lu

Doctoral Dissertations

"The purpose of this research was to develop dielectric films for high energy density capacitor applications. Also desired was to develop a deeper understanding of dielectric breakdown and electric energy storage related phenomena through simulation, theoretical analysis, and experimental investigation.

An analytical model incorporating Weibull dielectric strength statistics was developed to establish quantitative relationships between material properties and device performance of self-healing capacitors. The model is useful for designing high voltage capacitors and developing dielectric materials where the effects of electric field-dependent permittivity need to be considered.

In the experimental work, solution-cast poly(vinylidene difluoride) (PVDF) homopolymer PVDF films with high …

Modeling Aperture Radiation For Rf Interference Applications, Liehui Ren

Doctoral Dissertations

"The first topic proposes a rigorous method of moments(MoM) solution to evaluate the shielding effectiveness of a metallic enclosure with apertures on top wall by formulating a pair of coupled mixed potential integral equations (MPIEs). Application of Ewald transform to the computation of Green's function in the cavity yields fast convergence of series summation. Good agreements with a commercial tool, EMC studio, have proved the effectiveness of the proposed approach.

The second topic deals with prediction of electromagnetic interference radiation from components or interconnects in a printed circuit board by using convolution of the half-space Green's functions and the equivalent …

Low-Complexity Soft-Decision Feedback Turbo Equalization For Multilevel Modulations, Huang Lou

Doctoral Dissertations

"This dissertation proposes two new decision feedback equalization schemes suitable for multilevel modulation systems employing turbo equalization. One is soft-decision feedback equalization (SDFE) that takes into account the reliability of both soft a priori information and soft decisions of the data symbols. The proposed SDFE exhibits lower signal to noise ratio (SNR) threshold that is required for "water fall" bit error rate (BER) and much faster convergence than the near-optimal exact minimum mean square error linear equalizer (Exact-MMSE-LE) for high-order constellation modulations. The proposed SDFE also offers a low computational complexity compared to the Exact-MMSE-LE. The drawback of the SDFE …

5-Axis Tool Path Generation With Collision Detection For Finish Machining Of Freeform Surfaces, Jomy Francis

Masters Theses

"Research in the field of Tool path generation for freeform surfaces has been done intensively in the past. However, the main challenge that still exists is the computational efficiency related to the tool path generation. Tool path generation for freeform surface involves instantaneous calculation of new tool orientations which does not collide with the neighboring surfaces. Since the collision check of tool and neighboring surface is done repetitively at every instant of the tool, the calculations at every instant are to be computationally as easy as possible.

This thesis is composed of one paper. Paper I presents a novel extension …

Forward Converter For Solar Power Applications, Nickolas Arthur Mcfowland

Masters Theses

"Most solar arrays used today are connected in series and have tremendous power losses in partially shaded conditions. This document explores photovoltaic arrays in a parallel connection to reduce the power losses in other solar cell connected applications. The two main issues with any photovoltaic arrays are solar modules being shaded and the efficiency of the power converters used within the solar array. This thesis concentrates on alleviating these problems with the development of a two phase dc to dc forward converter with a snubber circuit as well as connecting a solar array in parallel to increase the performance in …

Formation Of Amyloid Fibrils By Diblock Peptides, Kunal Mukesh Naik

Masters Theses

"The objective of this study was to identify and then synthesize a series of peptides which were able to form fibrils rich in ß-sheet structure and to study the effect of the presence of surfaces on their formation. We decided to focus our experimental work on a family of peptides containing one "beta-sheet forming amino acid" and one 'alpha-helix forming amino acid'. This selection covers a wide range of hydrophillicites and charges and, by avoiding highly hydrophobic amino acids we can assure that the diblock peptides are soluble in a wide range of concentrations and solvent conditions. Three different diblocks …

Behavior Of Staged Externally Bonded Carbon Fiber Reinforced Polymer Sheets For Improved Ductility, Laura Marie Rathe

Masters Theses

"Fiber reinforced polymers (FRP) has become increasingly used for the retrofit of aging structures for increased lifespans and for the rapid repair of damaged structures. It has many advantageous such as ease in rapid installation, high strength-to-weight ratio, and corrosion resistance. The main disadvantage of the material is brittle behavior with little warning of impending failures. The main objective of this study is to develop a new system of FRP that exhibits a more ductile behavior. To achieve this objective, separate sheets of FRP were applied at various staged levels and thus engaged at different loads. Ductile behavior was evaluated …

Field Coupled Electrostatic Discharge Sensitivity Database, Zhen Li

Masters Theses

"Electrostatic Discharge (ESD) can disrupt the performance of an electronic system, like an MP3 player either by injected currents or by transient fields. It is possible to predict at least the approximate transient field levels inside a system, but it is difficult to determine the response of ICs subjected to these fields, as no IC specific data is available, and as it is often too involved to measure the sensitivity of every IC possibly used in a product. As deterministic solutions are difficult to achieve, a statistical approach has been selected in this research. The goal of this database for …

The Use Of Electrical Resistivity Tomography (Ert) To Delineate Water-Filled Vugs Near A Bridge Foundation, Jeremiah Chukwunonso Obi

Masters Theses

"A structural support was needed to strengthen the load-bearing capacity of an unnamed bridge foundation in Laclede County in South-Central Missouri due to increasing traffic volume and age of the bridge. This area is characterized by karstic features such as losing streams, underground caves and sinkholes. During the construction of a drilled shaft for the substructure, a few feet north of the north footing of the pier, voids were noted beneath a roughly 2 foot thick cap of dolomite rock. Because of this, there were concerns about the integrity of the rock beneath the existing bridge foundation. Consequently, subsurface investigation …

Dynamic Model-Based Systems Engineering Using Xml Metadata Interchange, Dustin Scott Nottage

Masters Theses

"Designing systems presents an engineer with numerous design choices based on multiple conditions and constraints. Base camp planning must take into account the number of soldiers, the permanency of the base, the location of the base, etc. To help alleviate the complexity of constructing a base camp, a model-based systems engineering approach is used. This method creates and integrates models for all of the facilities that can make a base camp, as well as interactions between facilities and required utilities for each. The goal is to have a camp design, and then solve a system of equations to solve for …

Robust Evolutionary Algorithms, Brian Wesley Goldman

Masters Theses

"Evolutionary Algorithms (EAs) have shown great potential to solve complex real world problems, but their dependence on problem specific configuration in order to obtain high quality performance prevents EAs from achieving widespread use. While it is widely accepted that statically configuring an EA is already a complex problem, dynamic configuration of an EA is a combinatorially harder problem. Evidence provided here supports the claim that EAs achieve the best results when using dynamic configurations. By designing methods that automatically configure parts of an EA or by changing how EAs work to avoid configurable aspects, EAs can be made more robust, …

Design And Development Of Ionic Liquid Dual-Mode Spacecraft Propellants, Steven P. Berg

Masters Theses

"Energetic ionic liquids capable of dual-mode chemical monopropellant or bipropellant and electric electrospray rocket propulsion are investigated. Following an extensive literature review, ionic liquids [Bmim][dca], [Bmim][NO₃], and [Emim][EtSO₄] are selected for study since their physical properties align well with the current state-of-the-art in chemical and electrospray propellants. Simulations show that these liquids will not be useful for monopropellant propulsion due to the prediction of solid carbon formation in the exhaust and performance 13-23% below that of hydrazine. Considering these ionic liquids as a fuel component in a binary monopropellant mixture with hydroxyl ammonium nitrate shows 1-4% improved specific impulse over …

Investigation Of Drillstring Vibration Reduction Tools, Mohammed Fayez Al Dushaishi

Masters Theses

"Drilling related problems such as drillstring vibration is an important cause of premature failure of drillstring components and drilling inefficiency. The vibration of drillstring interferes with measurement collected while drilling. In severe cases, drillstring vibration will lead to wellbore instability that will result in an increase in the operation cost. In the late 1980's, a lot of studies and techniques were developed to mitigate drillstring vibration and downhole vibration measurements were introduced to the industry in two forms; real time measurements and memory devices measurements

A study of drillstring vibration of three different wells located in the Norwegian North Sea …

Numerical Investigation Of Plasma Actuator Configurations For Flow Separation Control At Multiple Angles Of Attack, Thomas Kelsey West Iv

Masters Theses

"The primary objective of the study presented in this thesis was to analyze the effectiveness of aerodynamic plasma actuators as a means of active flow control over a low speed airfoil at multiple angles of attack each corresponding to two different flow separation mechanisms (i.e., laminar separation bubble and turbulent flow separation at stall conditions). Detailed parametric studies based on steady and unsteady Navier-Stokes simulations, modified to include the body force term created by the plasma actuator, were performed for a NACA 0012 airfoil at a chord Reynolds number of 10⁵. In particular, parametric studies were performed to investigate the …

Structural Analysis Of Microsatellites, Yezad H. Anklesaria

Masters Theses

"Satellite design, development, fabrication, testing and entry into service is a complex process. Each step of this process involves intricate steps to achieve the desired objective. This thesis summarizes a study relating to the area of development and testing of microsatellites to support qualification and eventually preparing a spacecraft for spaceflight. Students in the Space Systems Engineering laboratory (SSE Lab) in the Aerospace Engineering Program are in the process of developing a pair of microsatellites for a technology demonstration in space.

After the initial design of the spacecraft is completed in the design phase a significant amount of time is …

Gray Gas Analysis Of Radiative Preheating Effects On Shock Induced Combustion, Pratibha Raghunandan

Masters Theses

"The use of detonations in combustors has been receiving increased attention in recent times. The presence of shock waves in such combustors invariably poses the existence of two domains that present different physics for the flow processes. The variation of upstream temperature due to radiative heating by the products of combustion was given particular attention in the present study. The modeling of heat transfer across a normal shock wave of negligible thickness was done by considering the reactants and the products of combustion to be in radiative equilibrium with each other. The quantification of emissivity of the products of combustion …

Palynomorph And Palynofacies Assemblages Of Neutral-Alkaline And Acid Lakes South Of Norseman, Southern Western Australia, Lutfia Grabel

Masters Theses

"The Yilgarn Craton in Western Australia hosts hundreds of shallow ephemeral hypersaline lakes, the majority of which have acid to neutral pH values. As part of a multidisciplinary study of the evolution of hypersalinity and acidity in the region, three drill cores were studied for their palynofacies and palynomorph contents in order to characterize palynofloral response to environmental changes. Drill cores from two acid lakes, Prado Lake (PL1-09 and PL2-09) and Twin Lake West (TLW1-09), and the neutral-alkaline Gastropod Lake (GLE1-09) south of Norseman recovered Miocene to Holocene sediments of the Revenge and Polar Bear formations. Transmitted light microscopy was …

Multiple-Input Multiple-Output System On A Spinning Vehicle With Unknown Channel State Information, Aditya Muralidhar

Masters Theses

"This thesis work presents the investigations into the performance of a multiple-input multiple-output (MIMO) system with its transmitters on a spinning vehicle and no available channel state information (CSI) at the transmitter or the receiver. The linear least squares approach is used to estimate the channel and the estimation error is measured. The spinning is simulated based on a sample radiation pattern of a patch antenna. The antenna gains at different angles are obtained from this pattern and are used to model spinning. Spinning gives rise to a periodic component in the channel which can be estimated based on the …