Measurement and correlation of aerodynamic heating to surface corrugation stiffened structures in thick turbulent boundary layers

The flow conditions for which heating distributions were measured on corrugated surfaces and wavy walls in turbulent boundary layers are shown, along with the ratio of the displacement thickness to the roughness height versus the local edge Mach number for an equivalent smooth surface. The present data are seen to greatly extend the range of data available on corrugated surfaces in turbulent boundary layers. These data were obtained by testing fullscale corrugation roughened panels in the wall boundary layer of a supersonic and hypersonic wind tunnel. The experimental program used to obtain the data is described. The data are analyzed and correlated in terms of the pertinent flow and geometric parameters. The developed correlations are compared with the available thin boundary layer data, as well as with previously published correlation techniques

Aerothermodynamic Assessment of Corrugated Panel Thermal Protection Systems

The feasibility of using corrugated panels as a thermal protection system for an advanced space transportation vehicle was investigated. The study consisted of two major tasks: development of improved correlations for wind tunnel heat transfer and pressure data to yield design techniques, and application of the design techniques to determine if corrugated panels have application future aerospace vehicles. A single-stage-to-orbit vehicle was used to assess advantages and aerothermodynamic penalties associated with use of such panels. In the correlation task, experimental turbulent heat transfer and pressure data obtained on corrugation roughened surfaces during wind tunnel testing were analyzed and compared with flat plate data. The correlations and data comparisons included the effects of a large range of geometric, inviscid flow, internal boundary layer, and bulk boundary layer parameters in supersonic and hypersonic flow

Virial Masses of Black Holes from Single Epoch Spectra of AGN

We describe the general problem of estimating black hole masses of AGN by calculating the conditional probability distribution of M_BH given some set of observables. Special attention is given to the case where one uses the AGN continuum luminosity and emission line widths to estimate M_BH, and we outline how to set up the conditional probability distribution of M_BH given the observed luminosity, line width, and redshift. We show how to combine the broad line estimates of M_BH with information from an intrinsic correlation between M_BH and L, and from the intrinsic distribution of M_BH, in a manner that improves the estimates of M_BH. Simulation was used to assess how the distribution of M_BH inferred from the broad line mass estimates differs from the intrinsic distribution, and we find that this can lead to an inferred distribution that is too broad. We use these results and a sample of 25 sources that have recent reverberation mapping estimates of AGN black hole masses to investigate the effectiveness of using the C IV emission line to estimate M_BH and to indirectly probe the C IV region size--luminosity (R--L) relationship. We estimated M_BH from both C IV and H-Beta for a sample of 100 sources, including new spectra of 29 quasars. We find that the two emission lines give consistent estimates if one assumes R \propto L^{1/2}_{UV} for both lines.Comment: 38 pages, 6 figures, accepted by Ap

Quantified Uncertainty in Thermodynamic Modeling for Materials Design

Phase fractions, compositions and energies of the stable phases as a function of macroscopic composition, temperature, and pressure (X-T-P) are the principle correlations needed for the design of new materials and improvement of existing materials. They are the outcomes of thermodynamic modeling based on the CALculation of PHAse Diagrams (CALPHAD) approach. The accuracy of CALPHAD predictions vary widely in X-T-P space due to experimental error, model inadequacy and unequal data coverage. In response, researchers have developed frameworks to quantify the uncertainty of thermodynamic property model parameters and propagate it to phase diagram predictions. In previous studies, uncertainty was represented as intervals on phase boundaries (with respect to composition) or invariant reactions (with respect to temperature) and was unable to represent the uncertainty in eutectoid reactions or in the stability of phase regions. In this work, we propose a suite of tools that leverages samples from the multivariate model parameter distribution to represent uncertainty in forms that surpass previous limitations and are well suited to materials design. These representations include the distribution of phase diagrams and their features, as well as the dependence of phase stability and the distributions of phase fraction, composition activity and Gibbs energy on X-T-P location - irrespective of the total number of components. Most critically, the new methodology allows the material designer to interrogate a certain composition and temperature domain and get in return the probability of different phases to be stable, which can positively impact materials design

Adolescent women's daily academic behaviors, sexual behaviors, and sexually related emotions

PURPOSE: Emerging literature suggests that the emotional and behavioral experience in young women's romantic/sexual relationships may link to their academic success. However, existing studies' reliance on retrospective and/or global measures prevents detailed understanding of how and when specific academic experiences link to specific relationship experiences and whether these associations could vary over different school days. METHODS: Adolescent women (N = 387; 14-17 years at enrollment) were recruited from primary care adolescent clinics for a longitudinal cohort study of sexual relationships and sexual behavior. Participants provided daily diary information on academic behaviors, sexual emotions, and sexual behaviors. Chi-square and generalized estimating equation ordinal logistic or linear regression, respectively, assessed prevalence of sexual behaviors or differences in sexual emotions when academic behaviors did and did not occur. RESULTS: Young women's weekday reports of skipping school or failing a test were significantly linked to more frequent vaginal sex, less frequent condom use, and different levels of sexual emotions, on that same day. CONCLUSIONS: Our findings provide evidence that the emotional and behavioral experiences in young women's romantic/sexual relationships may impact young women's reaction to academic events

Martian Magma Evolution from Olivine-Hosted Melt Inclusions in Shergottites Using MELTS Models

Shergottites, the largest martian meteorite group, come from at least two geochemically different source reservoirs i.e. incompatible trace element (ITE)-depleted and enriched. The depleted shergottites are thought to be derived from an ITE-depleted mantle reservoir, while enriched shergottites are thought to be derived from an ITE-enriched mantle reservoir that represents late stage residual melt from a magma ocean or interaction with martian crust. Moreover, the martian crust is distinct from shergottites, by being highly oxidized, distinctly ITE-enriched, and older. The link between the crust and shergottite compositions is poorly understood. Here we model shergottite differentiation to resolve the origin of enriched shergottites and why the bulk martian crust is compositionally distinct from shergottites. Early formed olivine-hosted melt inclusions can provide primary melt composition from which the parental magma had crystallized and also information at different stages of crystallization during parent magma differentiation that leads to shergottite magma evolution as well as crustal contribution assessment. We analyzed olivine-hosted melt inclusions of two enriched poikilitic shergottites for their major, minor and trace element concentrations using electron microprobe and laser ablation ICP-MS. We corrected the melt inclusion compositions for post-entrapment re-equilibration with their host olivine. To comprehend the crystallization sequence of these rocks and whether the melt entrapment is consistent with the crystallization, we use MELTS models for equilibrium and fractional crystallization. The results of these models suggest that all the melts were trapped in a closed system progressive crystallization at 1150-1210 C within 1 kbar to 1 bar pressure that is equivalent to <8.5 km, implying melt entrapment without any additional exogenous materials

Development Methods and a Scenegraph Animation API for Cluster Driven Immersive Applications

This paper presents a scenegraph animation application programming interface (API), known as the Animation Engine, which was constructed for software developers to easily perform smooth transitions and manipulations to scenegraph nodes. A developer can use one line of code to enter the property, end state and number of frames to describe the animation, then the Animation Engine handles the rest in the background. The goal of the Animation Engine is to provide a simple API that integrates into existing applications with minimal effort. Additionally, techniques to improve virtual reality (VR) application performance on a large computer cluster are presented. These techniques include maintaining high frame rates with 4096 × 4096 pixel textures, eliminating extraneous network traffic and reducing long model loading time. To demonstrate the Animation Engine and the development techniques, an application known as the Virtual Universe was created. The Virtual Universe, designed to run in a six walled CAVE, allows users to freely explore a set of space themed environments. The architecture and development techniques for writing a stable immersive VR application on a large computer cluster, in addition to the creation of the Animation Engine, is presented in this paper