Probability models for the variation in the number of thunderstorm hits per day

Negative binomial distribution as new probability model for representing thunderstorm hit variation per day at Cape Kenned

Characterization and Utilization of 600 V GaN GITs for 4.5 kW Single Phase Inverter Design

Superior properties allow for faster switching and higher power density converters. However, the fast switching capability of GaN, while theoretically beneficial to converter design, presents several challenges due to the presence of printed circuit board (PCB) and device parasitics. Therefore, it is imperative that the results of device characterization reflect actual device behavior in order to adequately model the device for converter design. This thesis focuses on characterization and utilization of 600 V/30 A Gallium Nitride gate injection transistors, or GaN GITs. The experimental data from static and dynamic characterization was used to maximize the performance of the devices in each phase leg of a 4.5 kW, single-phase, full-bridge inverter. The impact of PCB and device parasitics on switching behavior was also investigated, and a trade-off study of switching loss, overshoot voltage, and dead time loss is presented. Device packaging is also of interest regarding the design of high-frequency devices. This thesis compares the impact of two package designs for the GIT device by designing two separate inverters with the same specifications utilizing the different packages. Finally, due to the lower critical energy of the GaN HEMT during a short circuit, this thesis studies the short-circuit robustness of the devices. The performance of a unique gate sensing protection scheme is compared between two different packages, and the impact of the gate drive and protection circuit design parameters on performance is evaluated

The Spring Floods of 1936: Picher and the Red Cross Unite

In the early 1900s, the Great Depression, great droughts, a huge tornado, and great floods roared through the United States, hitting the East Coast, the West Coast, and the Midwest. These troubling periods and incidents left many families without homes or incomes. Therefore, these families had no choice but to reach out to others for help, the main source being toward the Red Cross and places in America where trouble was much less than the disaster\u27s home front. Without the help of the Red Cross, the disaster stricken flood areas would not have survived

Barriers To Individuals Of Entering The Field Of Education

Institutional racism is prevalent in our society. It is the researcher’s belief that we must acknowledge the effects of racism in order to address the needs of individuals of color. The schools in our nation are an important place to start. The goal of this research is to create a list of barriers to individuals of color entering the field of education. Mixed methods research data collection and literature review aid in solving the research question: What are the barriers to individuals of color entering the field of education? A significant race gap has been noted by the researcher and it is believed to be due to the predominantly European American teaching force and an increasingly diverse student population. To prepare students for lives of high achievement and success, our schools need a teaching force that is not only highly effective but also ethnically and racially diverse. In recent years, progress has been made in attempting to attract individuals of color to the field of education, but major barriers still exist. Results suggest that without public investment and policy change, the race gap is expected to widen to the detriment of all students. Affecting not only the achievement of students of color, but also contributing to the shortage of teachers of color who can effectively meet the educational needs of all students

Miriam Williford Papers - Accession 1225

The Miriam Williford Papers relate to Dr. Miriam Williford’s personal and professional life. Dr. Williford (1926-1998) was a native of Rock Hill and was a student, professor, and administrator at Winthrop College for 40 years. Her papers include information concerning biographical data, correspondence, academic papers, publications and presentations, newspaper articles, photographs, and her personal interests. Dr. Williford’s areas of interest were in philosophies of Jeremy Bentham and Latin American History. Also consult Accession 157 for more information concerning Dr. Miriam Williford.https://digitalcommons.winthrop.edu/manuscriptcollection_findingaids/1981/thumbnail.jp