2,134 research outputs found
The application of Riegels' rule and time-like damping to transonic flow calculations
Finite difference relaxation solutions of the nonlinear small perturbation equations have proven reliable and successful in determining the transonic flowfields about thin airfoils. However, application of the small perturbation approach to thick airfoils usually results in an accuracy less than desirable. The incorporation of Riegels' Rule and time-like damping into the small perturbation approach and their application to thick and thin airfoils in transonic flow are discussed. Studies for thick and thin airfoils are presented. It is concluded that Riegels' Rule and damping should both be included in small perturbation transonic flow calculations
The 30-cm ion thruster power processor
A power processor unit for powering and controlling the 30 cm Mercury Electron-Bombardment Ion Thruster was designed, fabricated, and tested. The unit uses a unique and highly efficient transistor bridge inverter power stage in its implementation. The system operated from a 200 to 400 V dc input power bus, provides 12 independently controllable and closely regulated dc power outputs, and has an overall power conditioning capacity of 3.5 kW. Protective circuitry was incorporated as an integral part of the design to assure failure-free operation during transient and steady-state load faults. The implemented unit demonstrated an electrical efficiency between 91.5 and 91.9 at its nominal rated load over the 200 to 400 V dc input bus range
A Multiple Case Study of Memorial Crime Control Legislation and the Disconnect Between Legislative and Empirical Success
This thesis includes a qualitative, multiple case analysis by which “memorial crime control” (MCC) laws that were passed (successful) are compared to proposed MCC laws, which were not ultimately passed (unsuccessful). This comparison of MCC laws which were passed with those which were not allows for a better understanding of the nature and appeal of these laws. Additionally, the available peer reviewed research for MCC laws suggests that these laws are ineffective and can be counterproductive to their intended goals. In short, the available evidence indicates that the MCC laws that are “successful” in the political sense, are empirical failures. The goal of this thesis is to document and acknowledge the disconnect between legislative policy creation and scholarly research regarding, and to highlight the need for academic criminologists to take greater interest in the ‘hot topics’ that dominate legislative policy creation
A Comparison of School Suspension Rates and Number of Days Suspended between African-American and Caucasian Males
Racial discrimination plays a major role in out-of-school suspensions. Research shows that when students are suspended, they are removed from their learning environment, which can lead to poor academic achievement, lower graduation rates, and higher delinquency. The distribution of racial and ethnic minorities that are being suspended or expelled reveal disparities between the groups. Within the United States public school system, racial disparities have been documented over time to show African-American students are suspended from school at higher rates than any other race (Arcia, 2007; Bulter et al, 2012; Rocque, 2010; Skiba et al, 2002; Townsend, 2000).
School systems should be more proactive when dealing with student learning outcomes based on research and become more involved in student retention. Schools administrators should provide students with strong mentoring programs, family involvement activities and activities that build strong relationships with the parents and teachers of the students. The findings from the current study look at the impact out-of-school suspension has on African-American males and the outcomes for academic achievement. Since out-of-school suspension is increasing in many school districts across the United States, education leaders need to look at the effectiveness of suspension
Stabilization of cadmium selenide molecular clusters in zeolite Y. EXAFS and x-ray diffraction studies
South west Victoria 2012-2050 : are the settlements sustainable?
Over the past few decades coastal cities around the world have grown at an incredible rate. With this growth have come major challenges relating to land use planning, social relationships, economic development, bio diversity and the ecological footprint. The following paper selects three regional coastal towns (Warrnambool, Portland and Port Fairy) situated in the Australian state of Victoria, and addresses the issues of: increasing population and population density, open space requirements, residential density issues, public transport coverage, employment and employment density, a shifting economic climate, environment and climate change, water quality issues and building energy consumption with subsequent C02 emissions. Through a series of simulations the nine issues for each of the three cities will be examined from 2012 through to 2030. The goal is to highlight the current and simulated future impacts of the selected issues and propose solutions that could mitigate those impacts
EXAFS Analysis of Size-Constrained Semiconducting Materials
Semiconducting materials such as CdSe, CdS, PbS and GaP are included in crystalline zeolite Y and mordenite and structurally flexible ethylene-methacrylic acid copolymer solid matrices. EXAFS analysis reveals formation of species with dimensions of molecular size up to ca. 13 A in the crystalline hosts, while the polymer matrices allow agglomeration of larger semiconducting particles. Zeolite anchored structures are distinctively different to small particles with bulk crystal structure as usually found in colloidal systems
Race, Shelby County, and the Voter Information Verification Act in North Carolina
Shortly after the Supreme Court in Shelby County v. Holder struck down section 4(b) of the Voting Rights Act (VRA), the State of North Carolina enacted an omnibus piece of election- reform legislation known as the Voter Information Verification Act (VIVA). Prior to Shelby, portions of North Carolina were covered jurisdictions per the VRA’s sections 4 and 5—meaning that they had to seek federal preclearance for changes to their election procedures— and this motivates our assessment of whether VIVA’s many alterations to North Carolina’s election procedures are race-neutral. We show that in presidential elections in North Carolina black early voters have cast their ballots disproportionately in the first week of early voting, which was eliminated by VIVA; that blacks disproportionately have registered to vote during early voting and in the immediate run-up to Election Day, something VIVA now prohibits; that registered voters in the state who lack two VIVA-acceptable forms of voter identification, driver’s licenses and non-operator identification cards, are disproportionately black; that VIVA’s identification dispensation for voters at least seventy years old disproportionately benefits white registered voters; and, that preregistered sixteen and seventeen year old voters in North Carolina, a category of registrants that VIVA prohibits, are disproportionately black. These results illustrate how VIVA will have a disparate effect on black voters in North Carolina
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