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Master's Theses

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New Media Use Among High Achieving Adolescents, Kathleen Sara Alpizar Jan 2010

New Media Use Among High Achieving Adolescents, Kathleen Sara Alpizar

Master's Theses

To date, there has been relatively little research on adolescents and their new media use in school and at home. It is important to study this new media use because it can reveal much about how communication patterns are changing or evolving as adolescents incorporate new media seamlessly into their lives.

This study examined high achieving adolescents' use of new media at school and in their homes. Data were gathered at school through questionnaires and group discussion sessions. In addition, students kept diaries of all of their media use for one week.

This study revealed that high-achieving adolescents use new …


Interannual Differences In The Estuarine Ghost Shrimp, Neotrypaea Californiensis, Michael Buncic Jan 2010

Interannual Differences In The Estuarine Ghost Shrimp, Neotrypaea Californiensis, Michael Buncic

Master's Theses

The dispersal of invertebrate marine larvae can be expected to be wide ranging and show little population structure. Neotrypaea californiensis, the burrowing ghost shrimp, is found throughout the waters and coastal estuaries of the northwestern United States. Three hundred and four larval samples were used to study population diversity and structural difference occurring over the course of spawning periods from June to September in successive years (2005 and 2006). Data and genetic analysis from nucleotide sequencing of a section of the mitochondrial Cytochrome C oxidase subunit I (COI) gene suggest that ocean-borne larvae off the coast of Oregon and Washington …


Nonlinear Pushover Analysis Of A One-Story Precast Concrete Cladding System, Kai Sum Cheung Jan 2010

Nonlinear Pushover Analysis Of A One-Story Precast Concrete Cladding System, Kai Sum Cheung

Master's Theses

A nonlinear pushover analytical study of a precast concrete cladding system was completed. The analytical software used was SAP2000 (version 11.0.0). The specimen modeled is the three-dimensional corner of the first floor of a nine-story building. Thirty-one linear and nonlinear link elements were used to simulate the cladding connections. The results showed that inelastic behavior of these connections controls the behavior of the overall cladding system. At drift ratios of 0.0104, closure of the sliding connections at the top of the column cover panels occurs and resisting forces climb significantly with small additional lateral displacement. Forces quickly rise to levels …


Preparation Of Carbon Nanotube Based Device And Its Electrochemistry, Weiling Hsieh Jan 2010

Preparation Of Carbon Nanotube Based Device And Its Electrochemistry, Weiling Hsieh

Master's Theses

The purpose of this research is to develop methodologies for the exploitation of carbon nanotube thin films as chemical and electrochemical sensors. In this study we prepared thin films of carbon nanotubes (CNT) by solution casting methods and then used a novel hybrid electrochemical-conductometric method to measure the CNT film electrical conductivity as a function of electrochemical bias and stimulus. The bias between the CNT film and the contacting electrolyte and the bias between the opposite ends of the CNT film (referred to as K1 and K2) were simultaneously controlled - analogous to a transistor with an electrolyte gate. A …


Family Of Circulant Graphs And Its Expander Properties, Vinh Kha Nguyen Tran Nguyen Jan 2010

Family Of Circulant Graphs And Its Expander Properties, Vinh Kha Nguyen Tran Nguyen

Master's Theses

In this thesis, we apply spectral graph theory to show the non-existence of an

expander family within the class of circulant graphs. Using the adjacency matrix and its properties, we prove Cheeger's inequalities and determine when the equalities hold. In order to apply Cheeger's inequalities, we compute the spectrum of a general circulant graph and approximate its second largest eigenvalue. Finally, we show that circulant graphs do not contain an expander family.


Interferometric Porosimetry Of Porous Silicon With Radius Distribution Functions, Yu-Chun Lu Jan 2010

Interferometric Porosimetry Of Porous Silicon With Radius Distribution Functions, Yu-Chun Lu

Master's Theses

In this study a set of porous silicon (pSi) interferometric vapor sensor were made from p+ (~1 ohm-cm) and p++ (~0.005 ohm-cm) B-doped Si. The pSi layers were prepared electrochemically, stabilized either by ozone oxidation or 1-octene derivatization, and then characterized. FTIR reflection spectroscopy, scanning electron microscopy, and x-ray spectroscopy of pSi layer cross sections confirmed the completeness of the ozone oxidation and 1-octene hydrosilation. The performance of the pSi layers as interferometric ethanol vapor sensors was assessed by constructing calibration curves of optical thickness change versus ethanol partial pressure and using these to assess the detection limits for ethanol …


Observed Water Vapor Enhancement In Smoke Plumes, Caroline Marie Kiefer Jan 2010

Observed Water Vapor Enhancement In Smoke Plumes, Caroline Marie Kiefer

Master's Theses

Wildland fires cause the loss of life and billions of dollars in property damage every year in the US annually; thus, there is a need to better understand, predict, and manage both wildland and prescribed fires. Moisture released from combustion, in addition to added heat, can enhance buoyancy and convection, influencing fire behavior. Previous studies have shown a wide range of smoke plume moisture enhancement, but much uncertainty still exists in the quantitative values of moisture released during combustion. In this study, three measurement platforms were used to obtain in situ measurements of temperature and relative humidity during various prescribed …


Improvement Of A Propagation Delay Model For Cmos Digital Logic Circuits, Rodger Lawrence Stamness Jan 2010

Improvement Of A Propagation Delay Model For Cmos Digital Logic Circuits, Rodger Lawrence Stamness

Master's Theses

Propagation delay models, for CMOS Digital Circuits, provide an initial design solution for Integrated Circuits. Resources, both monetary and manpower, constrain the design process, leading to the need for a more accurate entry point further along in the design cycle. By verifying an existing propagation delay method, and its resulting delay model, calibration for any given process technology can be achieved. Literature reviews and detailed analysis of each step in the model development allow for greater understanding of each contributing parameter, and ultimately, adjustments to the model calibration result in a more accurate analytical model. An existing model was verified …


Acoustic Intensity Measurement System: Application In Localized Drug Delivery, Natalie Phipps Jan 2010

Acoustic Intensity Measurement System: Application In Localized Drug Delivery, Natalie Phipps

Master's Theses

Ultrasound is used for many applications in diagnostics and therapy. New developments are being made specifically for the use of therapeutic ultrasound for enhancement of localized drug delivery. The long term goal of this study is to find ultrasound pulsing sequences that will allow for controlled mass diffusion from hydrogel drug reservoirs. Developing this new method requires the calibration and characterization of therapy transducers using power and acoustic intensity measurements. Mechanical index, spatial peak pulse average intensity, and spatial temporal pulse average intensity calculations were made using hydrophone measurements set-up in a tank measurement system. These were compared to safety …


Performance Based Analysis Of Steel Buildings, Matthew Joseph Williams Dec 2009

Performance Based Analysis Of Steel Buildings, Matthew Joseph Williams

Master's Theses

This project investigated the performance of two separate building types, designed using ASCE 7-05, using the analysis procedures from ASCE 41-06. The results from the ASCE 41-06 analyses were compared to the expected performance level of Life Safety to determine the adequacy of the ASCE 7-05 design. ASCE 7-05 is intended to result in designs that perform to a Life Safety performance level regardless of the building type. A design using the AISC specifications for a steel Special Moment Frame and the lateral loads from ASCE 7-05 resulted in a building that slightly exceeded an Immediate Occupancy performance level for …


Nutrient Removal By Algae Grown In Co2-Enriched Wastewater Over A Range Of Nitrogen-To-Phosphorus Ratios, Laura Michelle Fulton Dec 2009

Nutrient Removal By Algae Grown In Co2-Enriched Wastewater Over A Range Of Nitrogen-To-Phosphorus Ratios, Laura Michelle Fulton

Master's Theses

In conventional wastewater treatment, biological nutrient removal (BNR) depends on bacterial assimilation for phosphorus removal and nitrification+denitrification for nitrogen removal, with the resulting loss of the fixed nitrogen resource. Alternatively, treatment by microalgae allows for assimilative removal of both phosphorus (P) and nitrogen (N) thereby avoiding the oxygen demand of nitrification and preserving fixed N for fertilizer use. Paddle wheel mixed high-rate ponds have much higher algal productivity than typical oxidation ponds, but even high-rate ponds often cannot grow sufficient algae to completely assimilate the N and P in domestic wastewater. Algae growth in high-rate ponds is usually limited by …


Dissolved Organic Matter Influences The Timing Of Embryonic Development Of The Purple Sea Urchin, Strongylocentrotus Purpuratus., Corbin J. Hodges Dec 2009

Dissolved Organic Matter Influences The Timing Of Embryonic Development Of The Purple Sea Urchin, Strongylocentrotus Purpuratus., Corbin J. Hodges

Master's Theses

Marine dissolved organic matter (DOM) comprises one of the largest carbon reservoirs on earth and has long been considered a potential energy source for marine invertebrates. The importance of DOM transport has been adequately demonstrated for unicellular organisms, where DOM can meet 100% of an organisms energy needs, but the effects of DOM uptake for marine metazoans are less well understood. In this study, three general areas involving the influence of DOM transport to marine invertebrates were explored. First, we assessed the effects of using seawater exposed to high intensity ultraviolet radiation (UVR) on the study organism; embryos of the …


Automation In Cs1 With The Factoring Problem Generator, Joshua B. Parker Dec 2009

Automation In Cs1 With The Factoring Problem Generator, Joshua B. Parker

Master's Theses

As the field of computer science continues to grow, the number of students enrolled in related programs will grow as well. Though one-on-one tutoring is one of the more effective means of teaching, computer science instructors will have less and less time to devote to individual students. To address this growing concern, many tools that automate parts of an instructor’s job have been proposed. These tools can assist instructors in presenting concepts and grading student work, and they can help students learn to program more effectively. A growing group of intelligent tutoring systems attempts to tie all of this functionality …


Galvanic Vestibular Stimulation Applied To Flight Training, Joel D. Hanson Dec 2009

Galvanic Vestibular Stimulation Applied To Flight Training, Joel D. Hanson

Master's Theses

Between 1994 and 2003 spatial disorientation resulted in at least 202 aircraft

accidents, 184 of them resulting in fatalities. Galvanic Vestibular Stimulation (GVS)

provides a cost effective and safe way to simulate spatial disorientation and

potentially test pilot’s vestibular system prior to aircraft operation. This experiment

investigates the use of GVS as an indicator of motion sensitivity and explores the

effects of GVS on flight simulation performance. Bilateral bipolar rectangular pulse

electrical stimulations were given to subjects via skin-mounted electrodes placed over

each mastoid process to stimulate the vestibular system with roll and yaw sensations.

Two studies were conducted in …


Measurement And Modeling Of Blocking Contacts For Cadmium Telluride Gamma Ray Detectors, Patrick R. Beck Dec 2009

Measurement And Modeling Of Blocking Contacts For Cadmium Telluride Gamma Ray Detectors, Patrick R. Beck

Master's Theses

Gamma ray detectors are important in national security applications, medicine, and astronomy. Semiconductor materials with high density and atomic number, such as Cadmium Telluride (CdTe), offer a small device footprint, but their performance is limited by noise at room temperature; however, improved device design can decrease detector noise by reducing leakage current.

This thesis characterizes and models two unique Schottky devices: one with an argon ion sputter etch before Schottky contact deposition and one without. Analysis of current versus voltage characteristics shows that thermionic emission alone does not describe these devices. This analysis points to reverse bias generation current or …


Two-Phase Boost Converter, Tadeus Gunawan Dec 2009

Two-Phase Boost Converter, Tadeus Gunawan

Master's Theses

A boost converter is one of the most efficient techniques to step up DC input voltage to a higher needed DC output voltage. The boost converter has many possible applications, such as in a photovoltaic system, hybrid car and battery charger. The proposed prototype in this report is a proof of concept that a Two-Phase Boost Converter is a possible improvement topology to offer higher efficiency without compromising any advantages readily offered by a basic boost. The prototype is designed to be able to handle up to 200 watts of output power with an input of 36 volts and an …


Extraction And Characterization Of Lipids From Microalgae Grown On Municipal Wastewater, Matthew W. Hutton Dec 2009

Extraction And Characterization Of Lipids From Microalgae Grown On Municipal Wastewater, Matthew W. Hutton

Master's Theses

Based on results of its Aquatic Species Program (1978-1996), which sought to develop algae-to-liquid fuel technology, the U.S. Department of Energy has suggested that algal wastewater treatment may be incorporated into biodiesel production schemes to reduce the operating costs of both processes. the purpose of the current research was to evaluate the triglycerides produced by wastewater-grown algae for their suitability as a fuel feedstock and to investigate the effectiveness of several solvent mixtures and extraction procedures at recovering lipids from fresh algae. The research involved two separate experiments. The first determined the quantity and quality of lipids produced over the …


Point-Of-Use Water Treatment Device For Disaster Relief, Patricia Marie Compas Dec 2009

Point-Of-Use Water Treatment Device For Disaster Relief, Patricia Marie Compas

Master's Theses

A point-of-use water treatment device and an optimal method for its use were developed. The specially-designed vessel is to be used with flocculation and disinfection agents, while also providing for clean water storage. Possible applications would be disaster relief, emergency preparedness, and outdoor recreation.


Detection And Tracking Of Stealthy Targets Using Particle Filters, Philip M. Losie Dec 2009

Detection And Tracking Of Stealthy Targets Using Particle Filters, Philip M. Losie

Master's Theses

In recent years, the particle filter has gained prominence in the area of target tracking because it is robust to non-linear target motion and non-Gaussian additive noise. Traditional track filters, such as the Kalman filter, have been well studied for linear tracking applications, but perform poorly for non-linear applications. The particle filter has been shown to perform well in non-linear applications. The particle filter method is computationally intensive and advances in processor speed and computational power have allowed this method to be implemented in real-time tracking applications. This thesis explores the use of particle filters to detect and track stealthy …


Single Cell Impedance Measurements Using Microfabricated Electrodes And Labview Graphical Programming, Stephanie Sophia Hernandez Dec 2009

Single Cell Impedance Measurements Using Microfabricated Electrodes And Labview Graphical Programming, Stephanie Sophia Hernandez

Master's Theses

This Master’s Thesis project consists of the research, design, and fabrication of a system that could perform broadband impedance measurements (1kHz-20Mhz) of single cells using National Instruments Labview data acquisition and programming in coordination with a single cell capture device. Presented first is the background information on cells and their electrical properties, along with background in micro-total-analysis systems as well as impedance spectroscopy. Experimental Methods are then discussed for the electrode design, cellular modeling in COMSOL, fabrication methods, and Labview 8.0 Set-up and programming. Measurements were performed using the single-cell capture device on saline, yeast cells, and a polysterene bead. …


Evaluating Head Gestures For Panning 2-D Spatial Information, Matthew O. Derry Dec 2009

Evaluating Head Gestures For Panning 2-D Spatial Information, Matthew O. Derry

Master's Theses

New, often free, spatial information applications such as mapping tools, topological imaging, and geographic information systems are becoming increasingly available to the average computer user. These systems, which were once available only to government, scholastic, and corporate institutions with highly skilled operators, are driving a need for new and innovative ways for the average user to navigate and control spatial information intuitively, accurately, and efficiently. Gestures provide a method of control that is well suited to navigating the large datasets often associated with spatial information applications. Several different types of gestures and different applications that navigate spatial data are examined. …


Development Of An Air-Cycle Environmental Control System For Automotive Applications, Christopher James Forster Dec 2009

Development Of An Air-Cycle Environmental Control System For Automotive Applications, Christopher James Forster

Master's Theses

An air‐cycle air conditioning system, using a typical automotive turbocharger as the core of the system, was designed and tested. Effects on engine performance were kept to a minimum while providing the maximum amount of cooling possible and minimizing weight and space requirements. A test stand utilizing shop compressed air was developed to measure component performance. An unmodified automotive turbocharger was tested initially as a baseline in a Reversed‐Brayton Cycle air cooling system. Once the baseline was established, another aircycle machine, assembled from commercial turbocharger components chosen individually to optimize their performance for cooling purposes, was tested to improve the …


Laser Scanning Confocal Microscopy (Lscm): An Application For The Detection Of Morphological Alterations In Skin Structure, Shea C. Smith Dec 2009

Laser Scanning Confocal Microscopy (Lscm): An Application For The Detection Of Morphological Alterations In Skin Structure, Shea C. Smith

Master's Theses

Laser scanning confocal microscopy (LSCM) is an optical imaging technique that provides improved resolution and sensitivity over conventional methods of optical microscopy. However, the cost of most commercial LSCM systems exceeds the financial limitations of many smaller laboratories. The design of a custom LSCM created at a fraction of the cost of a commercial model is discussed in this paper.

The increase in the incidence rate of skin cancer in the world today is alarming, as such, it is essential to provide an early, rapid and effective method for in vivo diagnostics of human skin tissue. LSCM is capable of …


The Electrical Properties Of Human Tissue For The Diagnosis And Treatment Of Melanoma Skin Cancer, Glenn Cameron Stante Dec 2009

The Electrical Properties Of Human Tissue For The Diagnosis And Treatment Of Melanoma Skin Cancer, Glenn Cameron Stante

Master's Theses

This thesis discusses the research, experimental methods, and data gathered for the investigation of a novel method for the diagnosis of melanoma skin cancer. First, a background about human skin tissue is presented. Then, a detailed description of melanoma along with current diagnosis techniques and treatment options are presented. In the experimental methods, the electrical properties of several types of tissue were analyzed, the purpose of which was to discover if a tissue type can be distinguished by its electrical properties alone. This would allow for the diagnosis of melanoma to be done by examining the electrical properties of the …


Latent Semantic Web Service Discovery And Composition Framework, (Winnie) Yuki Yick Dec 2009

Latent Semantic Web Service Discovery And Composition Framework, (Winnie) Yuki Yick

Master's Theses

A web service is a software system that supports interoperable machine to machine interaction over the network. It can be any kind of service provided on the web that can exchange data between applications. In simple terms, it is any program that is callable by another program across the web using standard protocols. Web services are special because they are independent of the platform, programming language, and model design. In current web applications, more businesses are gradually publishing their business as services over the web. This growing number of web services available within an organization and on the Web raises …


Arroyo Toad (Anaxyrus Californicus) Life History, Population Status, Population Threats, And Habitat Assessment Of Conditions At Fort Hunter Liggett, Monterey County, California, Jacquelyn Petrasich Hancock Dec 2009

Arroyo Toad (Anaxyrus Californicus) Life History, Population Status, Population Threats, And Habitat Assessment Of Conditions At Fort Hunter Liggett, Monterey County, California, Jacquelyn Petrasich Hancock

Master's Theses

The arroyo toad (Anaxyrus californicus) is a federally endangered species found on Fort Hunter Liggett, Monterey County, California. The species was discovered in 1996 and was determined to occupy 26.7 km of the San Antonio River from approximately 2.4 km northwest of the San Antonio Mission de Padua, to the river delta above the San Antonio Reservoir. The construction of the San Antonio Reservoir dam in 1963 isolated this northern population of arroyo toads. Through time, the Fort Hunter Liggett landscape has changed drastically. The land was heavily grazed by cattle until 1991, which considerably reduced vegetation in riparian areas. …


A Computational Model Of Apoptotic Osteocyte Correlation To Cortical Bone Remodeling Parameters, Michael Stephen Alexander Dec 2009

A Computational Model Of Apoptotic Osteocyte Correlation To Cortical Bone Remodeling Parameters, Michael Stephen Alexander

Master's Theses

The onset of osteoporosis caused by aging, disease states, and post-menopausal conditions significantly impacts patient quality of life, required healthcare funding, personal autonomy losses from increased fracture risk and the subsequent corrective surgery. Research has indicated that osteocyte apoptosis may be a key parameter in bone remodeling, raising the possibility of remodeling rate modulation for the mitigation of bone mass resorption. By developing therapies that target osteocyte apoptosis, it may be possible to prevent undesired bone remodeling activity while maintaining a healthy balance between damage formation in the form of microcracks induced by the strain environment and the removal of …


An Assessment Of Indoor Infiltration Parameters For Black Carbon From Residential Wood Combustion And The Spectral Dependence Of Light Absorption For Organic Carbon, Christopher John Malejan Dec 2009

An Assessment Of Indoor Infiltration Parameters For Black Carbon From Residential Wood Combustion And The Spectral Dependence Of Light Absorption For Organic Carbon, Christopher John Malejan

Master's Theses

Black carbon, a proxy for woodsmoke was measured indoors and outdoors for an occupied residence in Cambria, CA during the winter months of 2009. The purpose was to investigate the infiltration parameters: air exchange rate, deposition rate, and penetration factor. The second part of this study investigated the light absorption properties of organic carbon from residential wood combustion, the dominant fraction of woodsmoke.

To assess woodsmoke variation, a study conducted parallel to the one presented in this thesis (Ward, 2009), a grid array of personal emission monitors (PEMS) and aethalometers were placed in a small area, approximately one square kilometer, …


Drain Diverter, Hyung Joon Kim Dec 2009

Drain Diverter, Hyung Joon Kim

Master's Theses

The DI water is commonly used to rinse production wafers to remove mechanical and chemical residue without any problematic chemical reaction in rinse process. The semiconductor industry wants to save their manufacture cost and reduce the industrial residue by recycling the deionized water during CPM process. The conductivity in recycled DI water is integrated over the time period.

The Drain Diverter, deionized wafer filtering system, is the automated system that detects the level of ions and controls the drain system by using conductive probes. The system contains hysteresis loop, valve feedback, relay circuit, and facility interlock. The recycled water valve …


A Neural Network Approach To Border Gateway Protocol Peer Failure Detection And Prediction, Cory B. White Dec 2009

A Neural Network Approach To Border Gateway Protocol Peer Failure Detection And Prediction, Cory B. White

Master's Theses

The size and speed of computer networks continue to expand at a rapid pace, as do the corresponding errors, failures, and faults inherent within such extensive networks. This thesis introduces a novel approach to interface Border Gateway Protocol (BGP) computer networks with neural networks to learn the precursor connectivity patterns that emerge prior to a node failure. Details of the design and construction of a framework that utilizes neural networks to learn and monitor BGP connection states as a means of detecting and predicting BGP peer node failure are presented. Moreover, this framework is used to monitor a BGP network …