Open Access. Powered by Scholars. Published by Universities.®

Digital Commons Network™

Open Access. Powered by Scholars. Published by Universities.®

2010

Discipline
Institution
Keyword
Publication
Publication Type
File Type

Articles 59191 - 59220 of 59712

Full-Text Articles in Entire DC Network

Nmr Investigations Of Biomass-To-Fuel Conversions By Hydrothermal Processes, Wenjia Zhang Jan 2010

Nmr Investigations Of Biomass-To-Fuel Conversions By Hydrothermal Processes, Wenjia Zhang

Doctoral Dissertations

"Biofuels have gained significant attention as the most promising alternative energy and fuel supply for the near future because of two dominant reasons: first, biofuels are environmentally friendly; and second, they afford a sustainable technology. Biofuels can be synthesized from biomass by several different processes, among which, hydrothermal conversion is considered to be more energy efficient. However, scientific efforts to improve hydrothermal biomass-to-fuel (HT-BTF) conversion efficiencies are severely limited because little is known about the salient reaction mechanisms and intermediates. This study is aimed at a better understanding of the hydrothermal biomass degradation kinetics by advanced NMR spectroscopy and, accordingly, …

Go to article

Optimal Excitation Controllers, And Location And Sizing Of Energy Storage For All-Electric Ship Power System, Chuan Yan Jan 2010

Optimal Excitation Controllers, And Location And Sizing Of Energy Storage For All-Electric Ship Power System, Chuan Yan

Doctoral Dissertations

"The Navy's future all-electric ship power system is based on the integrated power system (IPS) architecture consisting of power generation, propulsion systems, hydrodynamics, and DC zonal electric distribution system (DC-ZEDS). To improve the power quality, optimal excitation systems, and optimal location and sizing of energy storage modules (ESMs) are studied. In this dissertation, clonal selection algorithm (CSA) based controller design is firstly introduced. CSA based controller design shows better exploitation ability with relatively long search time when compared to a particle swarm optimization (PSO) based design. Furthermore, 'optimal' small population PSO (SPPSO) based excitation controller is introduced. Parameter sensitivity analysis …

Go to article

Intelligent Power System Operation In An Uncertain Environment, Yusuf Yare Jan 2010

Intelligent Power System Operation In An Uncertain Environment, Yusuf Yare

Doctoral Dissertations

"This dissertation presents some challenging problems in power system operations. The efficacy of a heuristic method, namely, modified discrete particle swarm optimization (MDPSO) algorithm is illustrated and compared with other methods by solving the reliability based generator maintenance scheduling (GMS) optimization problem of a practical hydrothermal power system. The concept of multiple swarms is incorporated into the MDPSO algorithm to form a robust multiple swarms-modified particle swarm optimization (MS-MDPSO) algorithm and applied to solving the GMS problem on two power systems. Heuristic methods are proposed to circumvent the problems of imposed non-smooth assumptions common with the classical approaches in solving …

Go to article

Phosphate Post-Treatment Of Cerium-Based Conversion Coatings On Al 2024-T3, Daimon K. Heller Jan 2010

Phosphate Post-Treatment Of Cerium-Based Conversion Coatings On Al 2024-T3, Daimon K. Heller

Doctoral Dissertations

"Phosphate post-treatment of cerium-based conversion coatings (CeCCs) on high strength aluminum alloys can significantly improve corrosion resistance. As-deposited CeCCs exhibit corrosion pits and salt tails across the specimen surface after 3 days of exposure, but post-treated CeCCs have withstood 14 days of salt spray exposure without visibly corroding. The morphology, phase, and electrochemical properties of spray deposited CeCCs were affected by post-treatment parameters such as immersion time, solution temperature, and phosphate source. The best performing coatings were post-treated in aqueous orthophosphate solutions for at least 5 min at temperatures of at least 85⁰C. These conditions converted cerium hydroxy/peroxy species in …

Go to article

Effect Of Structure And Plasticizer On The Glass Transition Of Adsorbed Polymer, Boonta Hetayothin Jan 2010

Effect Of Structure And Plasticizer On The Glass Transition Of Adsorbed Polymer, Boonta Hetayothin

Doctoral Dissertations

"The effect of molecular mass on adsorbed poly(methyl methacrylate) (PMMA) on silica was determined using temperature-modulated differential scanning calorimetry (TMDSC). A two-component model, based on loosely-bound polymer (glass transition temperature, Tg, similar to that of bulk) and tightly-bound polymer (Tg higher than that of bulk) was used to interpret the thermograms. Similar amounts of tightly-bound polymer were found for 450 and 85 kDa PMMA (0.78 mg/m²), while the 32 kDa sample had a smaller amount (0.48mg/m²). A comparison of adsorbed PMMA, poly(vinyl acetate) (PVAc), and poly(methyl acrylate) (PMA) on silica was made using the same technique. The …

Go to article

Computational Methods For The Discovery And Analysis Of Genes And Other Functional Dna Sequences, Cyriac Kandoth Jan 2010

Computational Methods For The Discovery And Analysis Of Genes And Other Functional Dna Sequences, Cyriac Kandoth

Doctoral Dissertations

"The need for automating genome analysis is a result of the tremendous amount of genomic data. As of today, a high-throughput DNA sequencing machine can run millions of sequencing reactions in parallel, and it is becoming faster and cheaper to sequence the entire genome of an organism. Public databases containing genomic data are growing exponentially, and hence the rise in demand for intuitive automated methods of DNA analysis and subsequent gene identification. However, the complexity of gene organization makes automation a challenging task, and smart algorithm design and parallelization are necessary to perform accurate analyses in reasonable amounts of time. …

Go to article

The Marketing Value Of Graduate Certificate Programs In Higher Education: A Strategic Assessment, Susmitha Akula Jan 2010

The Marketing Value Of Graduate Certificate Programs In Higher Education: A Strategic Assessment, Susmitha Akula

Masters Theses

"The last five years have seen a significant increase in the popularity of non degree graduate certificates. This increase has raised questions about the value of graduate certificate programs from the perspective of students, alumni and industry employers. Do certificate programs provide real world skills and knowledge valuable to industry? Do they serve as effective recruiting tools for the university? Do they provide opportunities for students to meet their professional goals in terms of salary increase, promotions, and the like? The present research is specifically aimed at answering these questions. Surveys that assess perceptions of value of graduate certificates to …

Go to article

Mechanical Properties And Microstructure Study For Direct Metal Deposition Of 316l Stainless Steel, Tian Fu Jan 2010

Mechanical Properties And Microstructure Study For Direct Metal Deposition Of 316l Stainless Steel, Tian Fu

Masters Theses

"Direct metal deposition or laser cladding is a process capable of producing fully dense and net shape metal products and this process could be used on coating metal components in various engineering applications. This process has fast heating and cooling rates which can improve the surface hardness and provide excellent adhesion through metallurgical bond between coating material and substrate. This paper evaluated the laser deposited 316L stainless steel coating on 4340 steel, which is widely used for aircraft landing gear applications. The microstructure, micro-hardness and quantitative EDS were explored to verify the coating properties. The desired homogeneous microstructure and high …

Go to article

Calibration Of Resistance Factors For Axial Capacity Of Driven Pile Into Missouri Soil, Mulugeta Abay Kebede Jan 2010

Calibration Of Resistance Factors For Axial Capacity Of Driven Pile Into Missouri Soil, Mulugeta Abay Kebede

Masters Theses

"Over the past two decades the load resistance factor design (LRFD) has been accepted by the American Association for Transportation and Highway Officials (AASHTO) for the design of bridges. This approach is now gaining widespread popularity in the United States for substructure bridge design, including the design of driven pile foundations, as the states calibrate the geotechnical resistance factors for local geological conditions and practices. This study presents the geotechnical resistance factors calibrated for axially driven pile using the first-order reliability method (FORM) for the target reliability index of 2.33 and 3.0 based on 64 end-of-drives (EOD) and 22 beginning-of …

Go to article

Evaluation Of Alternative Methods For Surface Preparation And Deposition Of Cerium-Based Conversion Coatings On Aluminum Alloys, William J. Gammill Jan 2010

Evaluation Of Alternative Methods For Surface Preparation And Deposition Of Cerium-Based Conversion Coatings On Aluminum Alloys, William J. Gammill

Masters Theses

"This thesis investigates alternative surface preparation and deposition methods for cerium-based conversion coatings (CeCC) on high strength aluminum alloys. Cerium-based conversion coatings are being investigated as a more environmentally friendly replacement for chromium-based conversion coatings. Currently, the alloys are immersed in strong alkaline and acidic solutions to prepare the aluminum surfaces for conversion coating, in which immersion may not be suitable for all situations. Alternatives to this method were investigated, including wipe application of solution, ultrasonic processing in deionized water, and abrasive blasting with alumina. AI 7075-T6 test panels were prepared using each of these methods and compared to a …

Go to article

Sintering And Microstructural Effects On Mechanical Properties Of Zirconium Carbide-Tungsten Cermets, Melissa M. Giles Craft Jan 2010

Sintering And Microstructural Effects On Mechanical Properties Of Zirconium Carbide-Tungsten Cermets, Melissa M. Giles Craft

Masters Theses

"Zirconium carbide-tungsten cermets were prepared by in situ reaction sintering a mixture of zirconia and tungsten carbide. Tungsten is a refractory metal with a melting point of 3422⁰C; however, its mechanical strength decreases significantly with increasing temperature. One approach to improve the elevated temperature strength is to add ceramic particulates to the matrix. Zirconia and tungsten carbide were compacted and then reacted and sintered in a single step by heating to 2050⁰C. The resulting stoichiometric zirconium carbide-tungsten cermet had a relative density greater than 96%. Cermets with two different grain sizes were produced by altering the final sintering temperature. Sintering …

Go to article

"In Situ" Printed Circuit Board Material Extraction Procedure With Conductor Surface Roughness Study, Amendra Koul Jan 2010

"In Situ" Printed Circuit Board Material Extraction Procedure With Conductor Surface Roughness Study, Amendra Koul

Masters Theses

"Analysis of printed circuit board (PCB) behavior in a wide frequency range from tens MHz to at least 40 GHz is very important for modern high-speed digital design and assuring for signal integrity (SI). this analysis includes preliminary evaluation of per-unit-length parameters of the PCB transmission line and transmission line characteristics, such as propagation and attenuation constants, and also extraction of these parameters from measurements on real test vehicles. This thesis describes an impedance calculator tool, which can substantially speed up PCB design, and the second topic considered in this work is characterization of dielectric parameters of substrates of printed …

Go to article

Selective Solubilisation Of Single Walled Carbon Nanotubes Using Polycyclic Aromatic Hydrocarbons, Sourabhi Debnath Jan 2010

Selective Solubilisation Of Single Walled Carbon Nanotubes Using Polycyclic Aromatic Hydrocarbons, Sourabhi Debnath

Doctoral

Single-walled carbon nanotubes (SWCNTS) are proposed to be one of the most promising nanomaterials, with unique electronic and mechanical properties which lend themselves to a variety of applications. In all cases the quality of the SWCNT material is important, and for some applications it is paramount. Despite sustained efforts, all currently known SWCNT synthetic techniques generate significant quantities of impurities. They also grow in bundles or ropes and are largely insoluble in common organic solvents. SWCNTS can have a range of structures and their electronic properties (metallic or semiconducting) depend on their structure and as well on their diameters. Currently …

Go to article

Photopolymerizable Nanocomposites For Holographic Applications, Elsa Leite Jan 2010

Photopolymerizable Nanocomposites For Holographic Applications, Elsa Leite

Doctoral

Photopolymerizable nanocomposites with good optical properties consisting of an acrylamide based photopolymer and zeolite nanoparticles (Beta, zeolite A, AlPO-18, silicalite-1 and zeolite L) were fabricated and characterized for holographic applications. The colloidal zeolite solutions used in this project were characterized by several techniques including X-Ray Diffraction (XRD), Dynamic Light Scattering (DLS), Scanning Electron Microscopy (SEM) and Raman spectroscopy to ensure their successful synthesis. The dependence of grating performances in these nanocomposites on recording intensity, spatial frequency and zeolite concentration were studied. It was found that the incorporation of silicalite-1 nanoparticles or a small amount of zeolite A nanoparticles (up to …

Go to article

Visible And Hyperspectral Imaging Systems For The Detection And Discrimination Of Mechanical And Microbiological Damage Of Mushrooms, Edurne Gaston Jan 2010

Visible And Hyperspectral Imaging Systems For The Detection And Discrimination Of Mechanical And Microbiological Damage Of Mushrooms, Edurne Gaston

Doctoral

Horticultural products such as mushrooms are exposed to environmental conditions during their postharvest life, which may affect product quality. Loss of whiteness during storage is particularly important in the mushroom industry. Rough handling and distribution, fruiting body senescence and bacterial infections are among the main causes of mushroom discolouration. The aim of this work was to study the use of visible and hyperspectral imaging (HSI) systems for the detection and discrimination of mechanical and microbiological damage of mushrooms. This piece of research involved a) monitoring the browning of mushroom with visible computer imaging systems, b) investigating the effect of mechanical …

Go to article

Efficacy Of Ozone And Ultrasound For Microbial Reduction In Fruit Juice, Sonal Patil Jan 2010

Efficacy Of Ozone And Ultrasound For Microbial Reduction In Fruit Juice, Sonal Patil

Doctoral

Concerns have arisen regarding the microbiological safety of fruit juices due to a number of outbreaks associated with pathogens. Non-thermal technologies for the inactivation of microorganisms are of increasing interest to the food industry for the control of spoilage as well as safety concerns. The objective of this thesis was to investigate the efficacy of ultrasound and ozone treatments for control of microbial issues associated with fruit juices. Inactivation of Escherichia coli (ATCC 25922, NCTC 12900) using power ultrasound was found to be influenced by strain, prior acid adaptation and suspension liquid, but the effect was negated at the higher …

Go to article

Assessing The Application Of 3d Collaborative Interfaces Within An Immersive Virtual University, Gavin Mcardle, Bianca Schoen-Phelan, Michela Bortolotto Jan 2010

Assessing The Application Of 3d Collaborative Interfaces Within An Immersive Virtual University, Gavin Mcardle, Bianca Schoen-Phelan, Michela Bortolotto

Articles

The need to stimulate and engage students is of paramount importance within any learning scenario. Despite this, recent developments in online learning have failed to take this requirement into account. As a result e-learning courses which utilise traditional online learning management systems have a higher dropout rate than their classroom based counterparts. The attrition rate is attributed to boredom with the interfaces used to deliver learning material and also to the lack of opportunities to interact socially with others. Furthermore, being in a virtual environment imposes a whole new set of challenges onto users due to the distinct lack of …

Go to article

Dietary Energy Density As Marker Of Dietary Quality In Swedish Children And Adolescents: The European Youth Heart Study, Emma Patterson, J. Wärnberg, E. Poortvliet, John Kearney, M. Sjöström Jan 2010

Dietary Energy Density As Marker Of Dietary Quality In Swedish Children And Adolescents: The European Youth Heart Study, Emma Patterson, J. Wärnberg, E. Poortvliet, John Kearney, M. Sjöström

Articles

To investigate if dietary energy density is associated with measures of dietary quality (food group, micronutrient and macronutrient intakes) in children and adolescents.

Go to article

Water Analysis For Emerging Environmental Contaminants, Xiaoliang Cheng Jan 2010

Water Analysis For Emerging Environmental Contaminants, Xiaoliang Cheng

Masters Theses

"The presence of emerging environmental contaminants in water bodies used either as drinking water or for recreational purpose has received considerable attention in the recent years. The emerging environmental contaminants can be defined as a wide range of chemicals that have been determined in the environment which may present serious health risks for humans. The occurrence of these contaminants indicate that both household and industrial chemicals have been introduced to water resources, a wide variety of chemicals, such as disinfection byproducts, pharmaceutical and personal care products and so on, have been detected at cetiain levels in either water bodies or …

Go to article

Automation Of Cad Model Based Assembly Simulations Using Motion Capture, Anup Madhav Vader Jan 2010

Automation Of Cad Model Based Assembly Simulations Using Motion Capture, Anup Madhav Vader

Masters Theses

"The manufacturing industry often uses text and video as a supplement for worker training procedures. Unfortunately, text is often difficult to follow and video lends itself to occlusion issues. CAD based animations of assembly operations can overcome these shortcomings while offering greater potential for operations analysis and simulation flexibility. However, creating such CAD based training simulations manually is a time intensive task and many a times fail to reveal the practical assembly issues faced in the real world. Thus, it is highly beneficial to be able to automate these simulations using motion capture from a physical environment. This thesis research …

Go to article

Development Of Novel Backscatter Communication Systems Using A Multi-Hop Framework And Distributed Beamforming, Vikram Reddy Surendra Jan 2010

Development Of Novel Backscatter Communication Systems Using A Multi-Hop Framework And Distributed Beamforming, Vikram Reddy Surendra

Masters Theses

"The goal of this thesis it to develop a wireless networking framework for battery-free devices based on passive, backscatter communication. In contrast to traditional, active communication systems, where the radio signal has to be generated using large amount of energy from batteries, the passive systems reflect the RF signal. The information is encoded by modulating the reflected signal, which consumes significantly less energy than active transmission. The existing passive, backscatter systems have limited communication capabilities. For example, the Radio Frequency Identification (RFID) systems support short-distance, direct communication between active reader and passive tags. The communication range is limited due to …

Go to article

Magnetocaloric Effect In Thin Films And Heterostructures, Christopher Bauer Jan 2010

Magnetocaloric Effect In Thin Films And Heterostructures, Christopher Bauer

USF Tampa Graduate Theses and Dissertations

The goals of this work are the optimization of the magnetocaloric effect in Gadolinium thin film structures. We approach this issue from two directions, that of process optimization and of interface effects. Past results showed Gd2O3 in our Gadolinium thin films, and the presence of such oxide seemed to grow with the temperature at which the film was grown or annealed. Comparison of samples grown without chamber gettering to those that were gettered show differences in their structural and magnetic properties, and we conclude that gettering is an effective step in enhancing the quality of Gd thin …

Go to article

Spousal Crossover Effects Of Job Demands On Health, Rachel Jane Daniels Jan 2010

Spousal Crossover Effects Of Job Demands On Health, Rachel Jane Daniels

Dissertations and Theses

The primary goal of this dissertation was to examine the crossover effects of an individual's job demands on the perceived health of the spouse. Using a sample of grocery store employees and their partners, crossover relationships were examined for 90 dyads using Structural Equation Modeling. Although the models had good fit, the proposed direct crossover relationships of job demands on health were not supported. Job demands of one partner did not significantly predict health outcomes in the other partner; although follow-up analyses found significant crossover of women's job satisfaction on men's mental health scores. An additional crossover relationship was supported …

Go to article

The Centerpiece To Real Reform? Political, Legal, And Social Barriers To Reentry In California,, Eumi Lee Jan 2010

The Centerpiece To Real Reform? Political, Legal, And Social Barriers To Reentry In California,, Eumi Lee

Faculty Scholarship

No abstract provided.

Go to article

Exclude Evidence You Exclude Justice’? A Critical Evaluation Of Israel’S Exclusionary Rule After Issacharov, Binyamin Blum Jan 2010

Exclude Evidence You Exclude Justice’? A Critical Evaluation Of Israel’S Exclusionary Rule After Issacharov, Binyamin Blum

Faculty Scholarship

No abstract provided.

Go to article

Misuse Made Plain: Evaluating Concerns About Neuroscience In National Security, Emily Murphy, Kelly Loweberg, Brenda M. Simon, Amy Burns, Libby Greismann, Jennifer M. Halbleib, Govind Persad, David L.M. Preston, Harker Rhodes Jan 2010

Misuse Made Plain: Evaluating Concerns About Neuroscience In National Security, Emily Murphy, Kelly Loweberg, Brenda M. Simon, Amy Burns, Libby Greismann, Jennifer M. Halbleib, Govind Persad, David L.M. Preston, Harker Rhodes

Faculty Scholarship

No abstract provided.

Go to article

Alienated: A Reworking Of The Racialization Thesis After September 11, Ming Hsu Chen Jan 2010

Alienated: A Reworking Of The Racialization Thesis After September 11, Ming Hsu Chen

Faculty Scholarship

No abstract provided.

Go to article

Is There Monopsony In The Labor Market? Evidence From A Natural Experiment, Douglas O. Staiger, Joanne Spetz, Ciaran S. Phibbs Jan 2010

Is There Monopsony In The Labor Market? Evidence From A Natural Experiment, Douglas O. Staiger, Joanne Spetz, Ciaran S. Phibbs

Dartmouth Scholarship

Recent theoretical and empirical advances have renewed interest in monopsonistic models of the labor market. However, there is little direct empirical support for these models. We use an exogenous change in wages at Department of Veterans Affairs (VA) hospitals as a natural experiment to investigate the extent of monopsony in the nurse labor market. We estimate that labor supply to individual hospitals is quite inelastic, with short-run elasticity around 0.1. We also find that non-VA hospitals responded to the VA wage change by changing their own wages.

Go to article

A World Of Possibilities: Multimodalities, Collaboration And Equity In The Composition Classroom, Anicca Cox Jan 2010

A World Of Possibilities: Multimodalities, Collaboration And Equity In The Composition Classroom, Anicca Cox

Cal Poly Humboldt theses and projects

In this unbound project titled, A World of Possibilities: Multimodalities, Collaboration and Equality in the Composition Classroom I have shown some of the advantages of using multimodal writing instruction. Multimodal writing instruction uses a variety of methods that move beyond written text by incorporating visual, aural, cinematic or textual features together. This project focused on presenting multimodal approaches in the context of multiliteracies in order to achieve social justice and inclusion. The project is centered on collaborative methods and examines specific multimodalities to present possible techniques for incorporating these methods in a composition classroom. The goal of the project is …

Go to article

Sentencing Reform In California, Aaron J. Rappaport Jan 2010

Sentencing Reform In California, Aaron J. Rappaport

Faculty Scholarship

No abstract provided.

Go to article

First Prev Next Last