11,486 research outputs found
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
EU Inconsistencies Regarding Human Rights Treatment: Can the EU Require Czech Action as a Criterion for Accession?
Comment on Beth Innocenti’s “Paying a Cost of Metadialogue: Reasonable Observations and Another Example on Handling Unwarranted Retreats to Metadialogue”
Leadership in the Continuous Improvement Process
Companies are formed for many reasons, but without profitability, they will not survive. Therefore, it remains the focus of the company\u27s employees to maintain profitability. New ideas and improvements must be implemented continuously for the company to maintain and increase their profitability.
The employees responsible for continuously implementing these new ideas and improvements will significantly contribute to the success of the company and its profitability. The key to their success is the use of positive leadership and a continuous improvement process. This study presents two theories that support this claim: Masaaki lmai\u27s continuous improvement process, and James MacGregor Burns\u27 theory of leadership. Also included is a discussion of the effects of cultural and process change, leadership in the continuous improvement process, and John P. Kotter\u27s concept of leadership and management
Parental alienation and targeted parents: loss, coping, and social support
2017 Summer.Includes bibliographical references.As the phenomenon of parental alienation becomes more prevalent and recognized by professionals who work with families, focusing on the impact of parental alienation on the alienated parent is becoming progressively more important. Alienated parents often suffer some sort of loss of their child (e.g., emotional connection, physical contact, or both) as a consequence of parental alienation. Due to the nature of this loss, we argue that parental alienation can lead to ambiguous loss that the targeted parent must learn to cope with. The purpose of this study was to further understand the experiences of parents who are targeted in alienation cases, specifically their feelings of loss and grief through the loss of emotional and/or physical connection with their children, as well as the various social supports that may be used by these parents in an effort to cope with this loss. The original interview data was obtained from parents who claim to have been alienated from their child after a separation or divorce. In order to quantify the qualitative data, two researchers coded the transcripts based on the operational definitions. The researchers coded a subsample of 45 interviews with these alienated parents. The researchers tested correlations between physical contact and emotional connection between the alienated parent and child, as well as between the contact and social supports utilized. Zero order (Pearson) correlations revealed no significant associations. However, some interesting results and themes from this subsample were noted
United States v Arthur Young & Co.: Judicial Death Knell for Auditors’ Privilege and Suggested Congressional Resurrection
United States v Arthur Young & Co.: Judicial Death Knell for Auditors’ Privilege and Suggested Congressional Resurrection
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