Statics and strength of materials

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ISEC2006-99096 INCREASING THE PRODUCTIVITY OF SOLAR PHOTOVOLTAIC SYSTEMS

ABSTRACT State-sponsored incentives have played a significant role in driving the demand for residential and small commercial photovoltaic (PV) systems. All state incentive programs are tied to the power rating of the system, though some states also offer energy production incentives. Unfortunately, there is a disconnect between the power rating of a PV system and the energy that system produces over its lifetime. It is extremely important to consider system productivity, which goes well beyond the efficiency of the components. System productivity is tied directly to the structure of the array, not just the efficiency of the components and the quality of the installation. This paper examines the issues associated with improving solar PV system productivity. The focus is on comparing a series-parallel array configuration to a seriesstring array configuration and the impact on energy production. Partial shade is used to highlight substantial differences between the operation of the two array configurations. INTRODUCTION State-sponsored incentives have played a significant role in driving the demand for residential and small commercial photovoltaic (PV) systems. All state incentive programs are tied to the power rating of the system, though some states also offer energy production incentives Consideration of system productivity is extremely important. A more productive system is able to pay for itself more quickly, bringing greater economic benefit to the homeowner and better value to the agency that provided the installation incentives. System productivity goes well beyond component efficiency. It is tied directly to the structure of the array, not just the efficiency of the components and the quality of the installation. This paper examines issues associated with improving the productivity of solar PV systems. The following section discusses different approaches to system configuration. Subsequent sections address the issues that require attention to maximize P

Metric to Characterize Baseball Pitcher Fatigue

High volumes of baseball pitches thrown by an athlete are associated with fatigue, which can decrease performance and increase injury risk. A system to identify certain biomechanical factors that have been linked with pitcher fatigue would be beneficial for the sport as a method of providing objective quantifications of a player’s risk of becoming over-fatigued. The team used motion capture to evaluate collegiate and major league (Pittsburgh Pirates) level pitchers, and conducted data exploration and analysis of the results on the parallel datasets. This included factors such as mechanical variation, joint range of motion, rate of force development, performance metrics, kinetic chain, rest time, and joint forces/moments. From the team’s data exploration, select candidate biomechanical factors were identified as the strongest indicators of fatigue, and were used to develop a fatigue metric. This metric included three biomechanical factors/outcomes, which characterized a pitch as “fatigued” upon failure of these factors/outcomes. The results presented a correlation between an increase in “fatigued” pitches as the number of pitches thrown increased

Designing a Website to Increase the Accessibility of Romanian Disability Certificates

In 2006, Romania started its journey towards inclusion and protection for people with disabilities, but the progress made still needs reform. This project is a collaboration between the WPI project team and Code for Romania, and it proposes a solution in the form of a website that guides Romanians with disabilities who are seeking the financial, social, and legal benefits of a Romanian disability certificate. After conducting surveys and interviews with disabled Romanians and relevant NGOs, the team designed, built, and evaluated a prototype that digitizes the disability certification process for applicants and government employees. The potential benefits of the project to alleviate burdens of the disabled community could be historical for this commonly marginalized population