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- Creator:
- Alsemaan, Mohammad
- Description:
- Solar energy is probably the most abundant renewable energy which is of great importance to fundamentally solve the energy crisis problem if can be harvested extensively and efficiently. This dissertation reviews the solar energy conversion systems and focuses on analyzing and developing high efficiency single-stage three-phase solar inverter system. Firstly, the recently developed material for solar cell is reviewed, and the solar model is derived, as well as solar string model. Based on the output put characteristic of solar string, the current state-of-art MPPT technologies are discussed and the P&O method is adopted for simplification purpose. Then the system design of solar inverter is fully is performed. The hardware design provides the detail design guidelines for most key components and provide suggested component in the market for prototype construction. The latest GaN device is adopted to improve efficiency and six-channel compact driving chip is used to reduce converter size. After that, the control loop design for three-phase inverter is detailed, with current loop and voltage loop illustrated respectively. Finally, the simulation results for control loop design and MPPT control are provide to verify the feasibility of the previous design. Based on the structure of selected system and new semiconductor device adopted, potential high efficiency solar conversion system can be expected.
- Resource Type:
- Masters Thesis
- Campus Tesim:
- Fullerton
- Department:
- Department of Electrical Engineering
- Creator:
- Nassruldin, Lafa Taher
- Description:
- Soil is unlike other construction materials such as steel and concrete for which humans can control their properties. Therefore, it is important to investigate and test soil in order to predict its response to the construction loading. The coefficient of consolidation (Cv) and coefficient of permeability (k) are two of the dominant and fundamental geotechnical parameters that are used in many applications within the civil engineering discipline. These coefficients are used in dam construction on soft bedrock, erection of retaining walls in weak bearing soil and foundation design on poorly compaction soil. In this study, four types of minerals montmorillonite, kaolinite, illite and quartz were mixed in different proportions, and used to conduct one- dimensional consolidation tests, as summarized in Tiwari and Ajmera (2011). Seven different vertical pressures 3.47 psi, 6.94 psi, 13.89 psi, 27.78 psi, 55.56 psi, 111.11 psi and 222.22 psi were applied. In order to examine the influence of pore fluid chemistry, the soil samples were prepared with distilled water as well as with saline water as the pore fluid. Casagrande’s Logarithm of Time Method were used to estimate the coefficient of consolidation values for forty – two samples with distilled water as the pore fluid and twenty – four samples with saline water as the pore fluid. Also, Terzaghi’s equation was used to determine the coefficient of permeability for the mineral mixtures. The variations of the Cv and k with consolidation pressure and index properties for all mixtures with distilled water and saline water as the pore fluids were examined. It is observed that Cv for kaolinite and illite mixtures with distilled water and saline water as the pore fluids increases with an increase in the consolidation pressure. On the other hand, Cv values for the montmorillonite mixtures with distilled water as the pore fluid decrease with an increase in the consolidation pressure. The Cv values for the montmorillonite mixtures with saline water as the pore fluid increase with an increase in the consolidation pressure. All the soil mixtures with distilled water and saline water as the pore fluids experienced reduction in the values of the coefficient of permeability with the increase in the consolidation pressure. The coefficient of consolidation decreases with an increase in the liquid limit for the kaolinite, illite and montmorillonite mixtures with distilled water and saline water as the pore fluids. The relationship between the coefficient of consolidation and plasticity index for the mineral mixtures with distilled water and saline water as the pore fluids has the same trend as that with the liquid limit. Specifically, the coefficient of permeability decreases with an increase in the liquid limit and plasticity index for the kaolinite mixtures with distilled water and saline water as the pore fluids. Finally, the coefficient of permeability decreases with an increase in the liquid limit and plasticity index for the montmorillonite mixtures with distilled water and saline water as the pore fluids.
- Resource Type:
- Masters Thesis
- Campus Tesim:
- Fullerton
- Department:
- Department of Civil and Environmental Engineering
- Creator:
- Mozaffarpour Noori, Mohammad
- Description:
- The aim of this thesis is to provide a tool for contractors to select optimal equipment for projects, which will increase cost efficiency and reduce environmental impacts. The target geographic area for this research is the state of California, and the considered type of machinery is heavy construction equipment. In part, this research presents a modified mathematical model, as a decision-making tool, to minimize cost and emission of construction equipment, while meeting project requirements. The optimization model facilitates construction companies in selecting more efficient and sustainable equipment, while also avoiding penalties associated with non-compliance with the state’s environmental regulations. Such approach may lead to more profit by increasing the number of projects due to growing public sentiment towards environmentally friendly businesses. This model uses particular types of fleet data and project data. Construction equipment related data includes fleet size, equipment type, number, model, and year. Project related data includes project’s volumes, schedule, resources, and technical issues described by the contractors. Once this information was collected from equipment rental agencies throughout different geographic locations in California, a spreadsheet incorporated this information, along with mathematical calculations for estimated emissions, as well as the capacity for each type of equipment.
- Resource Type:
- Masters Thesis
- Campus Tesim:
- Fullerton
- Department:
- Department of Civil and Environmental Engineering
- Creator:
- Dang, Tristin Salazar
- Description:
- The goal of my research is to examine the ways women construct their sexuality within the socio-sexual spaces of bars and nightclubs. By using ethnographic qualitative methods, such as observations and in-depth interviewing, I attempt to understand how women construct their sexuality while navigating social constructions and masculine heteronormative controls. I look at women’s experiences with the sexual self, confidence, sexual scripts, and masculine sexual hegemony. My analysis of these themes, which elaborates women’s roles and interactions with men, offers a deeper understanding of how women come to present their sexual selves under the male hegemonic order of women’s sexuality. I also examine the ways in which women are cognizant of the expectations that exist in the socio sexual spaces such as bars and clubs. Their practical knowledge reveals the agency that exists within their performativity and desire by using clothing, dancing, drinking, socializing, kissing, and one- night stands to display sexual empowerment.
- Resource Type:
- Masters Thesis
- Campus Tesim:
- Fullerton
- Department:
- Department of Sociology
- Creator:
- Smith, Melinda
- Description:
- Gymnastics is a complex and progressive sport that is popular all over the world. Risk of injury is high due to the demands of training year round and increasing the difficulty of skills year after year. Research has focused on injury rates, but has not identified specific methods to identify risk and prevent injury in gymnastics. The Functional Movement Screen (FMS) is a tool that has shown efficacy in predicting injury in various populations. However, no research has used the FMS to predict injuries in gymnasts. This study performed the FMS on gymnasts training levels 7-10. Thirty-one gymnasts, ages 10-18, agreed to participate in this study and were screened with the FMS. Participants were tracked for 4.5 months. Two left the study during the first month and were not included in the data. Injuries were tracked during the participant’s pre and regular season. No significant differences were found between injured and non-injured gymnasts in relation to the overall and individual FMS tests. Surprisingly, injured gymnasts scored better on the FMS (mean = 15.00±3.25) compared to the non-injured gymnasts (mean = 13.61±1.97). Differences were found between level 7 and level 9 gymnasts for mean overall FMS score (level 7 = 16.17±1.33, level 9 = 12.37±2.77, p<0.05) and the trunk stability push up between levels 7 (2.67±0.82) and 9 (0.75±1.34) and levels 8 (2.62±1.06) and 9 (0.75±1.34). The results from this study suggest that the FMS cannot predict injury in gymnastics. However, it may be a useful tool to track changes in functional movement as gymnasts progress through the levels of gymnastics. iii TABLE OF CONTENTS ABSTRACT................................................................................................................... ii LIST OF TABLES......................................................................................................... v LIST OF FIGURES .................................................................
- Resource Type:
- Masters Thesis
- Campus Tesim:
- Fullerton
- Department:
- Department of Kinesiology
- Creator:
- Elliott, Daniel A.
- Description:
- This study explored an application of Social Judgment Involvement Theory in the higher education classroom. To accomplish this, an investigation of how highly sensitive issues that trigger high ego involvement was conducted to observe the effect upon the credibility of the instructor. The experiment explored how a student audience reacted to a politically charged message that fell within their latitudes of rejection. The first step was to identify the participants’ ego involvement with the politically sensitive issue. They then read a potentially disagreeable scenario and recorded their perception of the instructor’s credibility. There was a significant difference between the disagreement with the message evoking ego involvement and negative perceptions of instructor credibility. The study also measured which construct of credibility was affected the most by the disagreement. Students recorded a lower rating of perceived goodwill than trustworthiness or competence. However, the magnitude of that difference was minimal though still statistically significant. This study can inform instructors about that when discussing sensitive issues, there is a risk to credibility.
- Resource Type:
- Masters Thesis
- Campus Tesim:
- Fullerton
- Department:
- Department of Communications
- Creator:
- Quick, Donald Delliemer
- Description:
- Much of Southern California experiences a Mediterranean climate, with long, hot summers and cool, wet winters. Characteristic plants include the deeply-rooted shrubs collectively known as chaparral. Such species, including Malosma laurina (Laurel Sumac, Family Anacardiaciae) and Heteromeles arbutifolia (Toyon, Family Rosaceae), have the ability to tap cool, deep waters. Chaparral species face severe drought stress during the summer, which can be quantified in measurements of water status. Measuring water status continuously in situ can prove challenging, partially because some instruments are extremely sensitive to the extreme temperature gradients experienced by chaparral shrubs during the summer, and often require complex protocols for installation and maintenance. This study was conducted to develop two methods, stem psychrometry and measuring air flow into xylem, for using plant water status sensors on deeply-rooted chaparral shrubs. It was found that temperature gradients in large basal stems caused by ascent of cool xylem sap from deep soil layers can lead stem psychrometers to report overly-negative water potential readings midday. Attempts to correct for these temperature effects turned out to be unsuccessful, leading to a recommendation to install psychrometers on smaller branches up high. Air flow into xylem occurs during embolism spread or repair, possibly as stable nanobubbles are pulled through pit membranes, driven by the pressure gradient between air and xylem sap, and subsequently dissolved into the iii xylem sap. Using a liquid flow gauge to measure air flow into xylem, one set of measurements out of many attempts was completed, demonstrating the validity of the approach.
- Resource Type:
- Masters Thesis
- Campus Tesim:
- Fullerton
- Department:
- Department of Biological Sciences
- Creator:
- Ulloa, James
- Description:
- Bullying exists throughout the education system, though focus in research and discussions of bullying among students within public education are mostly placed on such interactions within the context of traditional K-12 education. While extant research examines the negative impacts that bullying produces for victims and bullies in the traditional school settings, there is a gap in literature examining bullying that occurs in continuation high schools. Additionally, there is a lack of information regarding how teachers may understand, view, and/or respond to bullying within the classroom. The current research draws on 10 in-depth, semi-structured qualitative interviews with teachers at continuation high schools to better understand their experiences with intrastudent bullying. Findings suggest that bullying occurs to achieve power and social status among students. Teachers situate bullying within a gendered context and, as a result, perceive incidents differently among male and female students. The results confirm extant research suggesting that teachers may become normalized to bullying interactions; however, findings expand on this literature by demonstrating how teacher intervention in bullying varies depending on how teachers define bullying, view the context of bullying, and whether they perceive their role as being both an educator and an interventionist.
- Resource Type:
- Masters Thesis
- Campus Tesim:
- Fullerton
- Department:
- Department of Sociology
- Creator:
- Salamanca, Jenny
- Description:
- This study focuses on the analysis of rainwater runoff from an extensive green roof system. Over time, space that was formally available for rainwater to properly infiltrate to the ground is being taken up by impervious built surfaces. Green roof technologies could be very beneficial in urban development, therefore the evaluation of the runoff quality is necessary to know if green roof systems act as a source of pollutants to receiving water bodies, or if they help mitigate contaminants that are washed off from the atmosphere and transfer to water bodies during rain events. The performance of green roof systems is highly dependent upon the season, temperature, wind condition, humidity, duration, and intensity of rainfall. The design of the green roof also plays an important part in the performance of the green roof, for which, material type, soil thickness, and maintenance influence the runoff quality. The green roof was analyzed for nutrients concentrations, pH, and conductivity of rainwater runoff. It was found that the green roof’s runoff had concentrations of nitrate, phosphate, and chloride ions. To investigate the amount of nutrients found in rainwater collected from different types of roofs, the green roof’s runoff nutrient concentrations were compared to those of a shingled roof. The pH and electrical conductivity of the rainwater runoff of the green roof were compared to those measured on a shingled roof as well.
- Resource Type:
- Masters Thesis
- Campus Tesim:
- Fullerton
- Department:
- Department of Civil and Environmental Engineering
- Creator:
- Rathod, Priyank Jayantilal
- Description:
- Recently there is a growing trend towards the emotional information to be used in the human-computer interaction. In order to get the correct interaction from the computer, a human has to provide the appropriate inputs. Inputs are recorded by various bio-medical sensors and processed for generating the appropriate data. For examples, Skin conductance is used to measure the skin potential between two nodes in the human body whereas heart rate as the name suggests is used to measure the variation in heart rate. Biomedical signals are generated using a neural network in a human body and used to estimate the emotions. As these signals are generated using the neural network, it is not possible to control it artificially. Due to this reason, it is the reliable source of the estimation of such information. Heart Rate Variability (HRV) and Galvanic Skin Response/Conductance (GSR) is changed when any type of emotion is induced in the human body. This change in signals represents certain characteristics which are used to estimate the emotions. Mainly there are two types of emotions which are negative emotions and positive emotions. Positive emotion includes happiness and normal behavior whereas negative emotion includes fear, anger and sadness. The current study investigated five different types of emotions. This research consists of measurement procedures for the emotion detection using biomedical signals.
- Resource Type:
- Masters Thesis
- Campus Tesim:
- Fullerton
- Department:
- Department of Computer Science