Shuttle landing facility cloud cover study: Climatological analysis and two tenths cloud cover rule evaluation

The two-tenths cloud cover rule in effect for all End Of Mission (EOM) STS landings at the Kennedy Space Center (KSC) states: 'for scattered cloud layers below 10,000 feet, cloud cover must be observed to be less than or equal to 0.2 at the de-orbit burn go/no-go decision time (approximately 90 minutes before landing time)'. This rule was designed to protect against a ceiling (below 10,000 feet) developing unexpectedly within the next 90 minutes (i.e., after the de-orbit burn decision and before landing). The Applied Meteorological Unit (AMU) developed and analyzed a database of cloud cover amounts and weather conditions at the Shuttle Landing Facility for a five-year (1986-1990) period. The data indicate the best time to land the shuttle at KSC is during the summer while the worst time is during the winter. The analysis also shows the highest frequency of landing opportunities occurs for the 0100-0600 UTC and 1300-1600 UTC time periods. The worst time of the day to land a shuttle is near sunrise and during the afternoon. An evaluation of the two-tenths cloud cover rule for most data categorizations has shown that there is a significant difference in the proportions of weather violations one and two hours subsequent to initial conditions of 0.2 and 0.3 cloud cover. However, for May, Oct., 700 mb northerly wind category, 1500 UTC category, and 1600 UTC category there is some evidence that the 0.2 cloud cover rule may be overly conservative. This possibility requires further investigation. As a result of these analyses, the AMU developed nomograms to help the Spaceflight Meteorological Group (SMG) and the Cape Canaveral Forecast Facility (CCFF) forecast cloud cover for EOM and Return to Launch Site (RTLS) at KSC. Future work will include updating the two tenths database, further analysis of the data for several categorizations, and developing a proof of concept artificial neural network to provide forecast guidance of weather constraint violations for shuttle landings

Culture of minimal influence: A study of Japanese university students’ attitudes toward plagiarism

The influence culture may have on East Asian students’ attitudes toward plagiarism has been a topic of much discussion in recent years, with many scholars believing that students from this region do not view plagiarism negatively. They argue that the students have little concept of individual word ownership and consequently feel copying the works of others should not be considered a transgression. Others, however, are wary of this culture argument, and suggest that it is seemingly premised on instances in which East Asian students have plagiarised on their English writing assignments. They submit that rather than culture, the underlying cause of student plagiarism more likely stems from a fear of academic failure due to struggles with a foreign language. Japanese students are often included among those who supposedly do not view plagiarism as morally wrong. In the present study, this theory is explored through examining data from a survey designed to gauge attitudes toward plagiarism and citation administered in 2011 to students at eight Japanese universities. Results indicate that Japanese students almost overwhelmingly view plagiarism as wrong and believe in the importance of providing citations to works they have used, although students from medical backgrounds may possibly be less concerned about the importance of citation than those from other fields. Moreover, contrary to beliefs held by both those who agree and disagree with the culture argument, results show that Japanese students seemingly receive more formal instruction regarding citation techniques than what has been commonly believed

Active DC-link capacitor harmonic current reduction in two-level back-to-back converter

The paper proposes a method of active switching harmonics current reduction in the DC-link capacitor of a two-level, three-phase, back-to-back converter. Based on the derived analytical solution for switching harmonic currents in the DC-link, it is shown that by specific control over the PWM carriers’ phase angles, the targeted harmonics of the rectifier and the inverter can be synchronized in phase such that their cancellation occurs in the DC-link capacitor. This synchronization is provided by harmonic phase feedback control. The three step procedure to implement the method is detailed in the paper. The effectiveness of the proposed approach is verified experimentally

Control design and voltage stability analysis of a droop-controlled electrical power system for more electric aircraft

This paper focuses on the analysis of a single DC bus multi-generator Electrical Power System (EPS) for future More Electric Aircrafts (MEA). Within such a single bus paradigm, the paper proposes a detailed control design procedure and provides a stability analysis based on the derivation of the output impedance of the source subsystem and input impedance of the load subsystem, including control dynamics. The single bus characteristic is analyzed and the stability properties of the EPS are investigated when supplying constant power loads. In addition, the paper highlights the impact on stability of the number of parallel sources and of the power sharing ratio. The theoretical analysis is instrumental in designing an optimally stable single DC bus EPS. The key findings are validated by experimental results

Final Technical Report

Since 1986 the Oregon State University Industrial Assessment Center (OSU IAC) has worked to increase the energy efficiency, productivity, sustainability, and competitiveness of US manufacturers; provide engineering students an education not available in the classroom; keep engineering faculty in contact with technology and challenges in Northwest industry; and reduce dependence on nonrenewable energy resources, both imported and domestic. Project Objective: Over the duration of this project (2002-2006), the OSU IAC worked to directly support and influence industrial decisions primarily regarding energy but also regarding sustainability and profitability through: Assessments & Follow-up: The OSU IAC performed 111 Industrial Assessments in Oregon, Washington, Idaho and Nevada to help industry identify and implement opportunities to increase energy efficiency, productivity, sustainability, and competitiveness Workshops Seminars Forums Etc: OSU IAC staff worked with regional peers to offer appropriate workshops and trainings as opportunities availed themselves. Graduating Excellent Energy Aware Professional Alumni: As technically capable, skilled written and verbal communicators, our alumni contributed to OSU IAC influence from their positions within industry, consulting organizations, utilities, and governmental and non governmental agencies. Tool Development: Analysis tools and guides originated at the OSU IAC extended our reach. The center continually worked to develop computer based analysis tools, evaluation checklists, analysis guide sheets for internal use and general sharing with industry, energy, and other professionals to assist them in efforts to improve US Industry. Impact: Over 20 years of activity the OSU IAC has typically performed 25 Industrial Assessments a year. On average, each year of 25 assessments has resulted in implemented projects that saved industry a total of: 25.3 TBTU in annual energy and $4.5 Million annually, with an average investment payback of one year. Over the duration of this project, while a number of recommendations are still under consideration for implementation, those already implemented have resulted in over$11 million in annual savings

An improved voltage compensation approach in a droop-controlled DC power system for the more electric aircraft

This paper proposes an improved voltage regulation method in multi-source based DC electrical power system in the more electric aircraft. The proposed approach, which can be used in terrestrial DC microgrids as well, effectively improves the load sharing accuracy under high droop gain circumstance with consideration of cable impedance. Since no extra communication line and controllers are required, it is easily implemented and also increases the system modularity and reliability. By using the proposed approach the DC transmission losses can be reduced and system stability is not deteriorated for normal and fault scenarios. In this paper optimal droop gain settings are investigated and the selection of individual droop gains as well as the proportional power sharing ratio has been described. Experimental results validate the effectiveness of the proposed method

Big Bands

USU Department of Music presents Big Bands.https://digitalcommons.usu.edu/music_programs/1146/thumbnail.jp

Big Bands

A performance by the USU Jazz Ensemble and USU Jazz Orchestra.https://digitalcommons.usu.edu/music_programs/1219/thumbnail.jp

The Music of Steely Dan

A performance featuring USU\u27s Big Band Jazz Ensembles.https://digitalcommons.usu.edu/music_programs/1206/thumbnail.jp