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Master's Theses

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A System For Natural Language Unmarked Clausal Transformations In Text-To-Text Applications, Daniel Miller Jun 2009

A System For Natural Language Unmarked Clausal Transformations In Text-To-Text Applications, Daniel Miller

Master's Theses

A system is proposed which separates clauses from complex sentences into simpler stand-alone sentences. This is useful as an initial step on raw text, where the resulting processed text may be fed into text-to-text applications such as Automatic Summarization, Question Answering, and Machine Translation, where complex sentences are difficult to process. Grammatical natural language transformations provide a possible method to simplify complex sentences to enhance the results of text-to-text applications. Using shallow parsing, this system improves the performance of existing systems to identify and separate marked and unmarked embedded clauses in complex sentence structure resulting in syntactically simplified source for …


Extraction Of Causal-Association Networks From Unstructured Text Data, Brett N. Bojduj Jun 2009

Extraction Of Causal-Association Networks From Unstructured Text Data, Brett N. Bojduj

Master's Theses

Causality is an expression of the interactions between variables in a system. Humans often explicitly express causal relations through natural language, so extracting these relations can provide insight into how a system functions. This thesis presents a system that uses a grammar parser to extract causes and effects from unstructured text through a simple, pre-defined grammar pattern. By filtering out non-causal sentences before the extraction process begins, the presented methodology is able to achieve a precision of 85.91% and a recall of 73.99%. The polarity of the extracted relations is then classified using a Fisher classifier. The result is a …


Cost Minimization For Hot Gas Defrost System, Jarubutr Dansilasirithavorn Jun 2009

Cost Minimization For Hot Gas Defrost System, Jarubutr Dansilasirithavorn

Master's Theses

Frost accumulation on evaporator coils has been a serious problem that decreases the efficiency of refrigeration systems. Many defrost methods have been used and hot gas defrost is the most common for industrial refrigeration applications. However, it is not a simple task to run an efficient hot gas defrost system. The duration and frequency of the defrost cycle should be properly determined so that the frost is melted but no additional heat transfer is transferred to the refrigerated space.

An experimental investigation was conducted at the Classic Salads Facility in Salinas, California. A single coil was instrumented to study frost …


Seismic Performance Of Unreinforced Masonry Walls Retrofitted With Post-Tensioning Tendons, Daniel Louis Lazzarini Jun 2009

Seismic Performance Of Unreinforced Masonry Walls Retrofitted With Post-Tensioning Tendons, Daniel Louis Lazzarini

Master's Theses

Unreinforced masonry (URM) structures have historically been regarded as structurally unsound in response to seismic events. The tendency for URM walls to collapse out-of-plane in a brittle manner is continually cause for concern. Retrofit of these walls is necessary in order to prevent severe damage and injury to occupants.

This paper is concerned with the retrofit of unreinforced masonry (URM) walls in response to out-of-plane loading. A retrofit design was developed and verified through structural testing. The selected retrofit technique incorporates vertical coring of URM walls to allow for the insertion of a single post-tensioning (PT) tendon. Tendons are spaced …


A Highly Abstracted Method Of Fpga-Based Development For Secondary Surveillance Radar Transpond Detection, James Penn Watt Jun 2009

A Highly Abstracted Method Of Fpga-Based Development For Secondary Surveillance Radar Transpond Detection, James Penn Watt

Master's Theses

Traditional FPGA-based digital design is based on writing hardware definition language (HDL) code from scratch. Time to market, cost of development, and the level of training required for designers all can be reduced with a simplified and abstracted design strategy. This project intends to demonstrate a graphical user interface (GUI) layer of abstraction on top of existing commercially produced design aids including MATLAB, Simulink, and Xilinx System Generator. This project performs and demonstrates a specific implementation example of a Secondary Surveillance Radar (SSR) message decoder as proof-of-concept for the abstracted design method. The abstracted digital design methods shown in this …


Preparation And Characterization Of Electrospun Poly(D, L-Lactide-Co-Glycolide) Scaffolds For Vascular Tissue Engineering And The Advancement Of An In Vitro Blood Vessel Mimic, Tiffany Richelle Pena Jun 2009

Preparation And Characterization Of Electrospun Poly(D, L-Lactide-Co-Glycolide) Scaffolds For Vascular Tissue Engineering And The Advancement Of An In Vitro Blood Vessel Mimic, Tiffany Richelle Pena

Master's Theses

PREPARATION AND CHARACTERIZATION OF ELECTROSPUN POLY(D,L-LACTIDE-CO-GLYCOLIDE) SCAFFFOLDS FOR VASCULAR TISSUE ENGINEERING AND THE ADVANCEMENT OF AN IN VITRO BLOOD VESSEL MIMIC

Tiffany Richelle Peña

Currently, an estimated 1 in every 3 adult Americans are affected by one or more cardiovascular complications. The most common complication is coronary artery disease, specifically atherosclerosis. Outcomes of balloon angioplasty treatments have been significantly improved with the addition of drug eluting stents to the process. Although both bare metal and drug eluting stents have greatly increased the effectiveness of angioplasty and decreased the occurrence of restenosis, several complications still exist. For this reason, the stent …


Designing A Microbial Prolyl Peptidase Delivery System For The Treatment Of Celiac Disease, Matthew J. Shurtleff Jun 2009

Designing A Microbial Prolyl Peptidase Delivery System For The Treatment Of Celiac Disease, Matthew J. Shurtleff

Master's Theses

Celiac disease is an autoimmune enteropathy resulting from the ingestion of gluten and gluten-like proteins from wheat, barley and rye in afflicted individuals. Indigestible gluten-derived peptides rich in proline residues are known to be responsible for eliciting the inappropriate immune response characteristic of the disease. In this investigation, surface level expression of prolyl peptidase activity by genetically engineered probiotic lactobacilli was postulated to be a possible treatment for this disease. Plasmid-based reporter vectors were constructed utilizing a novel, homology-based cloning technique to assess the expression and localization signals from the S-layer protein gene of Lactobacillus acidophilus. These plasmids were mutated …


Simulation Of An Oxidizer-Cooled Hybrid Rocket Throat: Methodology Validation For Design Of A Cooled Aerospike Nozzle, Peter Alexander Brennen Jun 2009

Simulation Of An Oxidizer-Cooled Hybrid Rocket Throat: Methodology Validation For Design Of A Cooled Aerospike Nozzle, Peter Alexander Brennen

Master's Theses

A study was undertaken to create a finite element model of a cooled throat converging/diverging rocket nozzle to be used as a tool in designing a cooled aerospike nozzle. Using ABAQUS, a simplified 2D axisymmetric model was created featuring only the copper throat and stainless steel support ring, which were brazed together for the experimental test firings. This analysis was a sequentially coupled thermal/mechanical model. The steady state thermal data matched closely to experimental data. The subsequent mechanical model predicted a life of over 300 cycles using the Manson-Halford fatigue life criteria. A mesh convergence study was performed to establish …


Spatial, Seasonal, And Size-Dependent Variation In The Diet Of Sacramento Pikeminnow In The Main Stem Of Chorro Creek, Central Coast California, Brian G. Dugas Jun 2009

Spatial, Seasonal, And Size-Dependent Variation In The Diet Of Sacramento Pikeminnow In The Main Stem Of Chorro Creek, Central Coast California, Brian G. Dugas

Master's Theses

This study examined the diet composition of ninety-nine Sacramento pikeminnow (150-410 mm [5.9-16 in] fork length [FL]) collected from the upper and lower main stem of Chorro Creek, Morro Bay Watershed, California in 2006. The goal of this study was to characterize the spatial and seasonal variability in the diet of Sacramento pikeminnow within Chorro Creek and to determine what proportion of the diet is represented by rainbow trout (Oncorhynchus mykiss) and their anadromous form (steelhead). Prey was identified in 88% of the samples collected in the early season and 84% of the samples collected in the late season. Fish …


Effects Of Experience On Maternal Behavior In Belding’S Ground Squirrels (Spermophilus Beldingi): Older And Wiser?, Mikael Langner May 2009

Effects Of Experience On Maternal Behavior In Belding’S Ground Squirrels (Spermophilus Beldingi): Older And Wiser?, Mikael Langner

Master's Theses

Maternal behavior is an important behavior because it influences whether or not raising one’s offspring is successful. Maternal experience is positively correlated with successful maternal behavior. This association is evident when comparing first-time mothers with mothers who have prior experience raising young. Life experience not related to raising young can also positively influence maternal behavior. In this work, the hypothesis that is tested is whether or not maternal experience enhances the ability of a female to assess the threat level of a situation. The model species used to conduct the study is the Belding ground squirrel (Spermophilus beldingi), …


Effect Of Starter Cultures On Lactobacillus Acidophilus Survival And Gene Expression In Yogurt, Elizabeth W. Ng May 2009

Effect Of Starter Cultures On Lactobacillus Acidophilus Survival And Gene Expression In Yogurt, Elizabeth W. Ng

Master's Theses

Probiotics, especially Lactobacillus acidophilus, strains have increasingly been incorporated into food products as dietary adjuncts due to their purported health benefits. Dairy products, especially yogurt, are frequently used as probiotic delivery systems. To realize therapeutic effects, it is important to consume a high amount of probiotics. However, maintaining a sufficient amount of viable probiotics in yogurt throughout the shelf life has been a challenge as starter cultures have shown to possess some deleterious effects on probiotic survival. The main objective of this thesis project was to determine the extent of antagonistic effects imposed by yogurt starter cultures (Lactobacillus delbrueckii ssp. …


City Of South Lake Tahoe Subdivision Ordinance: An Opportunity For Smart Growth, Sustainability, And Application Streamlining, Hilary Kay Hodges May 2009

City Of South Lake Tahoe Subdivision Ordinance: An Opportunity For Smart Growth, Sustainability, And Application Streamlining, Hilary Kay Hodges

Master's Theses

The City of South Lake Tahoe currently does not have an adopted subdivision ordinance. This has caused confusion about the approval process and regulatory requirements as well as delays in application processing. This Professional Project will explore the opportunity for the City to adopt a subdivision ordinance that would provide direction for subdivision design and approval and further the City’s smart growth and sustainability policies. However, there would need to be careful consideration for the potential increase in costs that are associated with additional fees or off-site improvement requirements. The Subdivision Ordinance would be written with the goals of achieving …


An Experiment On Integrated Thermal Management Using Metallic Foam, Derek M. Geiger May 2009

An Experiment On Integrated Thermal Management Using Metallic Foam, Derek M. Geiger

Master's Theses

This report details an approach to using metal foam heat exchangers inside an integrated thermal management system on a variable cycle engine. The propulsion system of interest is a variable cycle engine with an auxiliary, variable flow rate fan. The feasibility of utilizing an open-celled metallic foam heat exchanger in the ducting between the constant and variable-fans on this variable cycle engine to cool the avionics was explored using an experimental approach. Two heat exchangers, 6.3 inch width by 6.3 inch length by 0.5 inch thickness, were constructed from 20 and 40 pores per inch (PPI) metal foam and tested. …


Validation Of Linearized Flight Models Using Automated System-Identification, Keith Eric Rothman May 2009

Validation Of Linearized Flight Models Using Automated System-Identification, Keith Eric Rothman

Master's Theses

Optimization based flight control design tools depend on automatic linearization tools, such as Simulink®’s LINMOD, to extract linear models. In order to ensure the usefulness and correctness of the generated linear model, this linearization must be accurate. So a method of independently verifying the linearized model is needed. This thesis covers the automation of a system identification tool, CIFER®, for use as a verification tool integrated with CONDUIT®, an optimization based design tool. Several test cases are built up to demonstrate the accuracy of the verification tool with respect to analytical results and matches with LINMOD. Several common nonlinearities are …


Incremental Validation Of Formal Specifications, Paul S. Corwin May 2009

Incremental Validation Of Formal Specifications, Paul S. Corwin

Master's Theses

This thesis presents a tool for the mechanical validation of formal software specifications. The tool is based on a novel approach to incremental validation. In this approach, small-scale aspects of a specification are validated, as part of the stepwise refinement of a formal model.

The incremental validation technique can be considered a form of "lightweight" model checking. This is in contrast to a "heavyweight" approach, wherein an entire large-scale model is validated en masse.

The validation tool is part of a formal modeling and specification language (FMSL), used in software engineering instruction. A lightweight, incremental approach to validation is beneficial …


Agricultural Buffer Criteria For The City Of Arroyo Grande, Laura A. Pennebaker May 2009

Agricultural Buffer Criteria For The City Of Arroyo Grande, Laura A. Pennebaker

Master's Theses

The conservation of agricultural land is an important and challenging part of local and regional planning. Prime agricultural soils and viable agricultural operations serve as a vital part of California’s identity and economy. The conversion of land from farming to non-agricultural use significantly increases the potential for conflict between adjoining land uses and intensifies the pressure to develop adjacent farmland. Agricultural buffers serve as a tool to mitigate potential conflict between adjacent non-compatible land uses and protect both farming operations and residents from nuisance complaints. The City of Arroyo Grande has agricultural buffer policies which apply to development taking place …


Evaluation Of Herbicide Efficacy As Influenced By Adjuvant And Nozzle Type, Catherine L. (Grissom) Ansolabehere May 2009

Evaluation Of Herbicide Efficacy As Influenced By Adjuvant And Nozzle Type, Catherine L. (Grissom) Ansolabehere

Master's Theses

White clover (Trifolium repens) is a common and difficult weed to control in turfgrass as it is a highly visible and unsightly weed that disrupts the uniformity of the turfgrass surface. This weed is a serious problem in the turfgrass industry in California and there is a need for better methods of control. With more regulations on pesticides and less information about efficient application techniques, controlling white clover with available herbicides can be difficult.

Compatibility trials were conducted during the summer of 2005 to determine the compatibility of the herbicides and adjuvants planned for use in subsequent greenhouse and field …


Development Of A Laboratory Protocol For The Micropropagation Of Monterey Pines (Pinus Radiata), Año Nuevo Stand, Karen E. Wells May 2009

Development Of A Laboratory Protocol For The Micropropagation Of Monterey Pines (Pinus Radiata), Año Nuevo Stand, Karen E. Wells

Master's Theses

Monterey pine (Pinus radiata), a native tree to California and two Mexican islands, is important both ecologically and economically. Outside native stands, Monterey pines are grown for landscaping in California and on plantations around the world. Pitch canker, a disease caused by the fungus Gibberella circinata Nirenberg & O’Donnell (Fusarium circinatum Nirenberg and O'Donnell) is threatening the survival of Monterey pines. The disease currently affects Monterey pines in many parts of the world including the native stands. No effective chemical or biological control is available but some Monterey pines show resistance to the disease. The purpose of this project was …


A Flight Simulation Study Of The Simultaneous Non-Interfering Aircraft Approach, Brian H. Reel May 2009

A Flight Simulation Study Of The Simultaneous Non-Interfering Aircraft Approach, Brian H. Reel

Master's Theses

Using a new implementation of a NASA flight simulation of the Quiet Short-Haul Research Aircraft, autopilots were designed to be capable of flying both straight in (ILS) approaches, and circling (SNI) approaches. A standard glideslope coupler was sufficient for most conditions, but a standard Proportional-Integral-Derivative (PID) based localizer tracker was not sufficient for maintaining a lateral track on the SNI course. To track the SNI course, a feed-forward system, using GPS steering provided much better results.

NASA and the FAA embrace the concept of a Simultaneous, Non-Interfering (SNI) approach as a way to increase airport throughput while reducing the noise …


Harmonic Analysis Of A Static Var Compensated Mixed Load System, James David Ruckdaschel May 2009

Harmonic Analysis Of A Static Var Compensated Mixed Load System, James David Ruckdaschel

Master's Theses

As power electronic based controllers and loads become more prevalent in power systems, there is a growing concern about how the harmonics generated by these controllers and loads affect the power quality of the system. One widely used power electronic based load is the Variable Frequency Drive (VFDs) used to vary the speed of an induction motor; whereas a common example of a power electronic based controller used in power systems is the Static VAR Compensator (SVC) for improving a system’s power factor. In this thesis, the harmonic content and overall performance of a system including both a VFD and …


Development Of An In-Vitro Tissue Engineered Blood Vessel Mimic Using Human Large Vessel Cell Sources, Dimitri E. Delagrammaticas May 2009

Development Of An In-Vitro Tissue Engineered Blood Vessel Mimic Using Human Large Vessel Cell Sources, Dimitri E. Delagrammaticas

Master's Theses

Tissue engineering is an emerging field that offers novel and unmatched potential medical therapies and treatments. While the vast aim of tissue engineering endeavors is to provide clinically implantable constructs, secondary applications have been developed to utilize tissue-engineered constructs for in-vitro evaluation of devices and therapies. Specifically, in-vitro blood vessel mimics (BVM) have been developed to create a bench-top blood vessel model using human cells that can be used to test and evaluate vascular disease treatments and intravascular devices. Previous BVM work has used fat derived human microvascular endothelial cells (EC) sodded on an ePTFE scaffold. To create a more …


Implementation Of Physiologic Flow Conditions In A Blood Vessel Mimic Bioreactor System For The Evaluation Of Intravascular Devices, Marc Cody Dawson May 2009

Implementation Of Physiologic Flow Conditions In A Blood Vessel Mimic Bioreactor System For The Evaluation Of Intravascular Devices, Marc Cody Dawson

Master's Theses

The prevalence and devastating nature of cardiovascular diseases has led to many advancements in the therapies used to treat the millions of patients that suffer as a result of these conditions. As coronary artery disease (CAD) is the most common of these cardiovascular conditions, it is a major focus of research among the medical industry. Although lifestyle changes and drug therapies can treat early CAD, more advanced cases often require more definitive interventions. In conjunction with angioplasty, stenting of an occluded vessel has shown significant success in preventing restenosis. However, as with nearly every therapeutic process in the medical field, …


Comparison And Design Of Simplified General Perturbation Models (Sgp4) And Code For Nasa Johnson Space Center, Orbital Debris Program Office, Nicholas Z. Miura May 2009

Comparison And Design Of Simplified General Perturbation Models (Sgp4) And Code For Nasa Johnson Space Center, Orbital Debris Program Office, Nicholas Z. Miura

Master's Theses

This graduate project compares legacy simplified general perturbation model (SGP4) code developed by NASA Johnson Space Center, Orbital Debris Program Office, to a recent public release of SGP4 code by David Vallado. The legacy code is a subroutine in a larger program named PREDICT, which is used to predict the location of orbital debris in GEO. Direct comparison of the codes showed that the new code yields better results for GEO objects, which are more accurate by orders of magnitude (error in meters rather than kilometers). The public release of SGP4 also provides effective results for LEO and MEO objects …


Design And Control Considerations For A Skid-To-Turn Unmanned Aerial Vehicle, Tanner Austin Sims May 2009

Design And Control Considerations For A Skid-To-Turn Unmanned Aerial Vehicle, Tanner Austin Sims

Master's Theses

The use of Unmanned Aerial Vehicles (UAVs) are rapidly expanding and taking on new roles in the military. In the area of training and targeting vehicles, control systems are expanding the functionality of UAVs beyond their initially designed purpose. Aeromech Engineering’s NXT UAV is a high speed target drone that is intended to simulate a small aircraft threat. However, in the interest of increasing functionality, enabling NXT to accomplish wings level skidding turns provides the basis for a UAV that can simulate a threat from a missile. Research was conducted to investigate the aerodynamic and performance characteristics of a winged …


Target Tracking Using Various Filters In Synthetic Aperture Radar Data And Imagery, Jessica L. Kiefer May 2009

Target Tracking Using Various Filters In Synthetic Aperture Radar Data And Imagery, Jessica L. Kiefer

Master's Theses

This thesis explores the use and accuracy of several discrete-time image filters for the purpose of target tracking in Synthetic Aperture Radar imagery. Both extended targets and point targets are used for tracking, showing the need for different types of filters for each target type.

Monte Carlo analysis is performed on the results of the extended target filter results to determine the absolute mean-squared error between the filter prediction of the target centroid and the actual location of the target centroid. Two different filters were chosen for the extended target: Kalman and H Infinity.

Both the Kalman and H Infinity …


Shear Strength And Artificial Aging Characterization For Silicone Bonding Of Polyisobutylene (Pibs) Blends In Relation To Their Use As Lead Insulation Material, Shawn Grening May 2009

Shear Strength And Artificial Aging Characterization For Silicone Bonding Of Polyisobutylene (Pibs) Blends In Relation To Their Use As Lead Insulation Material, Shawn Grening

Master's Theses

In order to take advantage of the properties of poly(styrene-isobutylene-styrene) PIBS and PIB based blends as lead insulation materials, they must be able to sufficiently bond to the various materials that make up the cardiac device. The bonded PIBS must be able to withstand the mechanical stress and corrosive environment of the human body due to the long term use of these devices. Based on the component requirements of lead insulation, the first objective of this study was to perform an initial screening of multiple PIBS / stainless steel / silicone adhesive combinations. The specific polymers of interest were PIBS, …


The Benefit Of Foliar Applied Copper Fertilizer On Romaine Lettuce Grown In Low Copper Soils Of The Coastal Santa Maria, California, Emmy R. Williams Apr 2009

The Benefit Of Foliar Applied Copper Fertilizer On Romaine Lettuce Grown In Low Copper Soils Of The Coastal Santa Maria, California, Emmy R. Williams

Master's Theses

The importance of trace elements nutrients to vegetable crops has received more attention in recent years. Accordingly this experiment investigated the benefit of foliar applied copper fertilizer on romaine lettuce (Lactuca Sativa Longifolia) grown in low soil Copper (Cu) concentration in the coastal Santa Maria, California. The various rates of Cu fertilizer applied include untreated (control), 100, 200, 400 and 800 grams per acre of CuSO4.5H 2O, using a one time and a split application methods. Three consecutive individual experimental fields were established starting in late spring through the fall of 2008. The soil texture was a loam in all …


The Development And Pilot Of A Culinary Intervention Designed Using The Social Cognitive Theory To Teach Nutrition To Adolescent Girls, Julie Anne Chessen Apr 2009

The Development And Pilot Of A Culinary Intervention Designed Using The Social Cognitive Theory To Teach Nutrition To Adolescent Girls, Julie Anne Chessen

Master's Theses

In the past 20 years, the way in which food is prepared has rapidly changed. Convenience has become a way of life and Americans have replaced meals made from scratch with meals that are quick and easy. During that time, body mass index has risen steadily. The prevalence of overweight and obesity among children has become common in the American population. “Pink Chefs,” a six-week culinary intervention for middle school girls 12 to 14-years-old, was developed and piloted to combat childhood obesity by teaching nutrition through basic cooking skills. The social cognitive theory was used as the theoretical framework. The …


Bottom-Up Ontology Creation With A Direct Instance Input Interface, Charles C.H. Wei Apr 2009

Bottom-Up Ontology Creation With A Direct Instance Input Interface, Charles C.H. Wei

Master's Theses

In general an ontology is created by following a top-down, or so called genus-species approach, where the species are differentiated from the genus and from each other by means of differentiae [8]. The superconcept is the genus, every subconcept is a species, and the differentiae correspond to roles. To complete it a user organizes data into a proper structure, accompanied with the instances in that domain in order to complete the construction of an ontology. It is a concept learning procedure in a school, for example. Students first learn the general knowledge and apply it to their exercise and homework …


Bamboo: An Alternative Building Material For Urban Ethiopia, Bewketu Z. Kassa Apr 2009

Bamboo: An Alternative Building Material For Urban Ethiopia, Bewketu Z. Kassa

Master's Theses

This project explores the potential of bamboo as an alternative building material for low cost housing units suitable for urban Ethiopia. The rational for the application of bamboo comes from its abundance throughout the country, and its proven physical properties that equate it to other building material like timber, steel and concrete. The proposed bamboo based design solution concentrates on simplification of construction methods, prefabrication of structural components and vertical densification of housing units, addressing the lack of skilled labor, cost of construction time and urban land respectively. An understanding of the design solution was established by constructing a full-scale …