Breaking down the delta wing vortex: The role of vorticity in the breakdown process

Experimental x-wire measurements of the flowfield above a 70 and 75 deg flat plate delta wing were performed at a Reynolds number of 250,000. Grids were taken normal to the wing at various chordwise locations for angles of attack of 20 and 30 deg. Axial and azimuthal vorticity distributions were derived from the velocity fields. The dependence of circulation on distance from the vortex core and on chordwise location was also examined. The effects of nondimensionalization in comparison with other experimental data is made. The results indicate that the circulation distribution scales with the local semispan and grows in a nearly linear fashion in the chordwise direction. The spanwise distribution of axial vorticity is severely altered through the breakdown. The axial vorticity components with a negative sense, such as that found in the secondary vortex, seem to remain unaffected by changes in wind sweep or angle of attack, in direct contrast to the positive components. In addition, the inclusion of the local wing geometry into a previously derived correlation parameter allows the circulation of growing leading edge vortex flows to be reduced into a single curve

Visualization of leading edge vortices on a series of flat plate delta wings

A summary of flow visualization data obtained as part of NASA Grant NAG2-258 is presented. During the course of this study, many still and high speed motion pictures were taken of the leading edge vortices on a series of flat plate delta wings at varying angles of attack. The purpose is to present a systematic collection of photographs showing the state of vortices as a function of the angle of attack for the four models tested

Price Level Convergence Among United States Cities: Lessons for the European Central Bank

We study the dynamics of price indices for major U.S. cities using panel econometric methods and find that relative price levels among cities mean revert at an exceptionally slow rate. In a panel of 19 cities from 1918 to 1995, we estimate the half-life of convergence to be approximately nine years. These estimates provide an upper bound on speed of convergence that participants in European Monetary Union are likely to experience. The surprisingly slow rate of convergence can be explained by a combination of the presence of transportation costs, differential speeds of adjustment to small and large shocks, and the inclusion of non-traded good prices in the overall price index.

System size dependence of strangeness production at 158 AGeV

Strange particle production in A+A interactions at 158 AGeV is studied by the CERN experiment NA49 as a function of system size and collision geometry. Yields of charged kaons, phi and Lambda are measured and compared to those of pions in central C+C, Si+Si and centrality-selected Pb+Pb reactions. An overall increase of relative strangeness production with the size of the system is observed which does not scale with the number of participants. Arguing that rescattering of secondaries plays a minor role in small systems the observed strangeness enhancement can be related to the space-time density of the primary nucleon-nucleon collisions.Comment: 5 pages, 3 figures, Presented at Quark Matter 2002, Nantes, Franc

Evaluation of Risk Management Methods for Satsuma Mandarin

Simulation of production budgets were used to compare net discounted returns and the distribution of returns under alternative risk-mitigation scenarios. Results indicate that the combination of freeze protection and crop insurance increases expected net discounted 20-year returns while decreasing the downside risk. Break-even prices ranged from $.257 to$.289 per pound. Crop insurance returns were constant across price.Satsuma oranges, freeze protection, crop insurance, production budget, simulation, Crop Production/Industries, Farm Management, Risk and Uncertainty, C63, D81, Q12,

Mandarin Market Segments Based on Consumer Sensory Evaluations

Ninety-five consumers in seven grocery stores tasted unidentified peeled sections of three mandarins (a tangerine, a satsuma, and a clementine), and provided demographic and purchase information. Forty-four percent of the respondents preferred tangerines, 34 percent satsumas, and 22 percent clementines. The probability of preferring each of type of mandarin was estimated from internal quality analysis of paired samples, as well as from demographic and purchase responses. Model simulations were used to recommend harvest standards for satsumas based on Brix-to-acid ratios.Demand and Price Analysis, Food Consumption/Nutrition/Food Safety,

Dignity and Discrimination: Employment Civil Rights in the Workplace and in Courts

Employment civil rights and the litigation associated with enforcing them are a complex interplay of public and private employers, regulatory agencies, and federal courts. When an employee loses a job or their position in an employing organization, the financial effects are very real. If the employee makes a claim of discriminatory treatment using the employer’s human resources complaint processes or with the EEOC or state equivalent, they often face workplace retaliation and even termination. Using interviews conducted with parties to employment civil rights lawsuits, this article argues that the regime of employment civil rights in the United States can be conceived as perpetuating dignity takings (and occasionally dignity restorations) because (1) the state sanctions/permits/gives deference to management in ways that allow discrimination and loss of earnings and (2) does it in a way that allows and perpetuates dehumanizing infantilization which demonstrates that plaintiffs face dehumanizing stereotyped treatment in the workplace and in courts