Equine Reproduction and Genetics

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Horse Nutrition

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An analytical basis for assaying buried biological contamination Interim report

Assay techniques for determining biological contamination of spacecraft material

Multiple Boundary Layer Instability Modes with Nonequilibrium and Wall Temperature Effects Using LASTRAC

Prediction and control of boundary layer transition from laminar to turbulent is important to many flow regimes and vehicle designs, including vehicles operating at hypersonic conditions where nonequilibrium effects may be encountered. Wall cooling is known to affect the instability characteristics of the boundary layer and subsequently the transition location. Design considerations, including material failure and fuel chemistry, require the use of actively cooled walls in hypersonic vehicles, further motivating the study of wall temperature effects on top of the considerations of reducing heat flux, drag, and uncertainty. In this work, we analyze the stability of a boundary layer with chemical and thermal nonequilibrium on a Mach 20, 6 wedge. We investigate the effects of wall temperature on multiple unstable modes individually and on the integrated growth of disturbances along the surface. We use the LAngley Stability and TRansition Analysis Code (LASTRAC) to evaluate boundary layer stability, using capabilities implemented by the authors. Included are results that address chemical nonequilibrium with both thermal equilibrium and nonequilibrium

Boundary Layer Stability and Laminar-Turbulent Transition Analysis with Thermochemical Nonequilibrium Applied to Martian Atmospheric Entry

As Martian atmospheric entry vehicles increase in size to accommodate larger payloads, transitional ow may need to be taken into account in the design of the heat shield in order to reduce heat shield mass. The mass of the Thermal Protection System (TPS) comprises a significant portion of the vehicle mass, and a reduction of this mass would result in fuel savings. The current techniques used to design entry shields generally assume fully turbulent flow when the vehicle is large enough to expect transitional flow, and while this worst-case scenario provides a greater factor of safety it may also result in overdesigned TPS and unnecessarily high vehicle mass. Greater accuracy in the prediction of transition would also reduce uncertainty in the thermal and aerodynamic loads. Stability analysis, using e(sup N) -based methods including Linear Stability Theory (LST) and the Parabolized Stability Equations (PSE), offers a physics-based method of transition prediction that has been thoroughly studied and applied in perfect gas flows, and to a more limited extent in reacting and nonequilibrium flows. These methods predict the amplification of a known disturbance frequency and allow identification of the most unstable frequency. Transition is predicted to occur at a critical amplification or N Factor, frequently determined through experiment and empirical correlations. The LAngley Stability and TRansition Analysis Code (LASTRAC), with modifications for thermochemically reacting flows and arbitrary gas mixtures, will be presented with LST results on a simulation of a high enthalpy CO2 gas wind tunnel test relevant to Martian atmospheric entry. The results indicate transition caused by modified Tollmien-Schlichting waves on the leeward side, which are predicted to be more stable and cause transition slightly downstream when thermochemical nonequilibrium is included in the stability analysis for the same mean flow solution

The Nature and the Degree of the Relationship between Chronic Absenteeism and Student Achievement in a Large Metropolitan School District and a Small School District in Florida

The Bring It 180 study provides insight and awareness into the importance of student attendance and its influence on student achievement. This study examines the nature and degree of the relationship between chronic absenteeism and academic proficiencies. The research findings identify meaningful correlations between attendance and student achievement in two Florida school districts

The Case for GMOs: Dealing with Clashes between Property Rights and Health and Safety Concerns

A comparative analysis of international decisions concerning genetically modified organism (GMO) controversies reveals the judicial inconsistency that is often applied to the property rights of GMO producers and researchers. Courts often find that there are strong property right interests in GMOs, but when these rights clash with health and safety concerns, they are often minimized or completely forgotten; therefore, future growth in biotechnology is inhibited. This Note proposes a solution to this issue that better takes into account all stakeholders and allows for future investment and research into GMOs. The solution draws upon the lessons learned from current regulatory and enforcement regimes and international agreements governing GMOs. To arrive at this conclusion, this Note analyzes multiple cases concerning GMO controversies. These cases have been selected because their decisions have either gone against the national regulatory policy or public opinion. Further, this Note looks at the economic effects that these decisions have had on their respective countries