Integrated Flight Performance Analysis of a Launch Abort System Concept

This paper describes initial flight performance analyses conducted early in the Orion Project to support concept feasibility studies for the Crew Exploration Vehicle s Launch Abort System (LAS). Key performance requirements that significantly affect abort capability are presented. These requirements have implications on sizing the Abort Motor, tailoring its thrust profile to meet escape requirements for both launch pad and high drag/high dynamic pressure ascent aborts. Additional performance considerations are provided for the Attitude Control Motor, a key element of the Orion LAS design that eliminates the need for ballast and provides performance robustness over a passive control approach. Finally, performance of the LAS jettison function is discussed, along with implications on Jettison Motor sizing and the timing of the jettison event during a nominal mission. These studies provide an initial understanding of LAS performance that will continue to evolve as the Orion design is matured

Summary Report on Transport of Contaminants in the Subsurface: The Role of Organic and Inorganic Colloidal Particles

A meeting on ''Transport of Contaminants in the Subsurface: Role of Organic and Colloidal Materials'' was held on October 5-9, 1986, in Manteo, North Carolina. The meeting was part of the series of International Seminars on the Subsurface held by the Subsurface Transport Program o f the Office of Health and Environmental Research of the U.S. Department of Energy. The meeting was organized by Frank Wobber (OHER/DOE) and John McCarthy (Oak Ridge National Laboratory). The purpose of the meeting was to review current knowledge about the role played by colloids on the mobility of contaminants in the subsurface environment, and to identify important long-term research needs in this area. Participants included senior researchers in this field from national laboratories, government agencies, universities, and research institutes in four countries. Recent findings on the occurrence and nature of colloidal material in the subsurface as well as on the association of colloids with organic, metal, and radionuclide contaminants were presented and discussed. Field studies have demonstrated that colloidal particles do move through aquifers and that radionuclides have been transported much further than predicted due to their association with mobile colloids in the groundwater. The consensus of the meeting was that colloids do occur in the subsurface environment, are capable of binding organic and inorganic contaminants, and do alter the mobility of Contaminants. A major difficulty in understanding and predicting the role of colloids is their heterogeneous nature that hampers precise chemical characterization. Clay and metal oxide colloids can be formed or dissolved due to changes in solution chemistry in the aquifer. Organic colloids have variable and diverse functional groups, making it difficult to predict their association with metal and radionuclide contaminants Some important advances were reported toward understanding the assembly of organic colloids and the nature of their interactions with organic contaminants. Major research needs identified by the participants included studies in real systems on the occurrence of colloids in subsurface environments, and more rigorous characterization of the physical and chemical properties of the colloidal material. Methods for sampling colloids need to be improved to avoid production of artifacts during collection. In summary, the meeting concluded that colloidal material is important in contaminant transport and that further research in this area will significantly improve our capacity to predict the movement of energy-related contaminants in subsurface environments

The Conflicted Nature of Food Security Policy: Balancing Rice, Sugar and Palm Oil in Indonesia

Effective Protection of Fundamental Rights in a pluralist worl

A Process and Outcome Evaluation of a Shelter for Homeless Young Women

To evaluate the processes and outcomes of a short-term shelter, both quantitative and qualitative data were gathered via participant observation, focus group interviews with shelter staff and residents, and individual interviews with a sample of 40 young women who had been homeless prior to using the shelter. The process evaluation showed that the shelter staff strived to utilize an empowerment philosophy in their relationships with residents, but that there were many challenges to implementing this philosophy. The outcome evaluation showed that, at a 3-month follow-up, the participants reported significant improvements in housing, income, independence, and life satisfaction, but most continued to experience poverty and a number of other difficulties. The results were discussed in terms of the implications for future research and the value and limitations of shelters for dealing with homeless youth. The need for more sustained and comprehensive program interventions and supportive social policies was underscored

Magnetic fields and Sunyaev-Zel'dovich effect in galaxy clusters

In this work we study the contribution of magnetic fields to the Sunyaev Zeldovich (SZ) effect in the intracluster medium. In particular we calculate the SZ angular power spectrum and the central temperature decrement. The effect of magnetic fields is included in the hydrostatic equilibrium equation by splitting the Lorentz force into two terms one being the force due to magnetic pressure which acts outwards and the other being magnetic tension which acts inwards. A perturbative approach is adopted to solve for the gas density profile for weak magnetic fields (< 4 micro G}). This leads to an enhancement of the gas density in the central regions for nearly radial magnetic field configurations. Previous works had considered the force due to magnetic pressure alone which is the case only for a special set of field configurations. However, we see that there exists possible sets of configurations of ICM magnetic fields where the force due to magnetic tension will dominate. Subsequently, this effect is extrapolated for typical field strengths (~ 10 micro G) and scaling arguments are used to estimate the angular power due to secondary anisotropies at cluster scales. In particular we find that it is possible to explain the excess power reported by CMB experiments like CBI, BIMA, ACBAR at l > 2000 with sigma_8 ~ 0.8 (WMAP 5 year data) for typical cluster magnetic fields. In addition we also see that the magnetic field effect on the SZ temperature decrement is more pronounced for low mass clusters ( ~ 2 keV). Future SZ detections of low mass clusters at few arc second resolution will be able to probe this effect more precisely. Thus, it will be instructive to explore the implications of this model in greater detail in future works.Comment: 20 pages, 8 figure

A Semiotic Approach for Guiding the Visualizing of Time and Space in Enterprise Models

Part 2: Organizational Semiotics and ApplicationsInternational audienceEven if geographical aspects such as location are included already in the Zachman framework (as the where-perspective), it is not common to have detailed geographical aspects included in enterprise models. Cartography is the science of visualizing geographical information in maps. Traditionally the field has not included conceptual relationships that you find in enterprise models. Both cartography and enterprise modelling have developed guidelines for obtaining high quality visualizations. SEQUAL is a quality framework developed for understanding quality of models and modelling languages based on semiotic theory. In cartography such frameworks are not common. An adaptation of SEQUAL in the context of cartographic maps called MAPQUAL has been presented earlier. Differences between quality of maps and quality of conceptual models, pointing to guidelines for combined representations have been performed, and we try in this paper to investigate the utility of these guidelines in a simple trial. The result of the trial is presented, indicating that it is possible to represent conceptual, temporal, and spatial aspects in the same models in many ways, but that the choice of main perspective should depend on participant appropriateness

Measurement of νˉμ\bar{\nu}_{\mu} and νμ\nu_{\mu} charged current inclusive cross sections and their ratio with the T2K off-axis near detector

We report a measurement of cross section $\sigma(\nu_{\mu}+{\rm nucleus}\rightarrow\mu^{-}+X)$ and the first measurements of the cross section $\sigma(\bar{\nu}_{\mu}+{\rm nucleus}\rightarrow\mu^{+}+X)$ and their ratio $R(\frac{\sigma(\bar \nu)}{\sigma(\nu)})$ at (anti-)neutrino energies below 1.5 GeV. We determine the single momentum bin cross section measurements, averaged over the T2K $\bar{\nu}/\nu$-flux, for the detector target material (mainly Carbon, Oxygen, Hydrogen and Copper) with phase space restricted laboratory frame kinematics of $\theta_{\mu}$500 MeV/c. The results are $\sigma(\bar{\nu})=\left( 0.900\pm0.029{\rm (stat.)}\pm0.088{\rm (syst.)}\right)\times10^{-39}$ and $\sigma(\nu)=\left( 2.41\ \pm0.022{\rm{(stat.)}}\pm0.231{\rm (syst.)}\ \right)\times10^{-39}$in units of cm$^{2}$/nucleon and$R\left(\frac{\sigma(\bar{\nu})}{\sigma(\nu)}\right)= 0.373\pm0.012{\rm (stat.)}\pm0.015{\rm (syst.)}$.Comment: 18 pages, 8 figure

Fitting the integrated Spectral Energy Distributions of Galaxies

Fitting the spectral energy distributions (SEDs) of galaxies is an almost universally used technique that has matured significantly in the last decade. Model predictions and fitting procedures have improved significantly over this time, attempting to keep up with the vastly increased volume and quality of available data. We review here the field of SED fitting, describing the modelling of ultraviolet to infrared galaxy SEDs, the creation of multiwavelength data sets, and the methods used to fit model SEDs to observed galaxy data sets. We touch upon the achievements and challenges in the major ingredients of SED fitting, with a special emphasis on describing the interplay between the quality of the available data, the quality of the available models, and the best fitting technique to use in order to obtain a realistic measurement as well as realistic uncertainties. We conclude that SED fitting can be used effectively to derive a range of physical properties of galaxies, such as redshift, stellar masses, star formation rates, dust masses, and metallicities, with care taken not to over-interpret the available data. Yet there still exist many issues such as estimating the age of the oldest stars in a galaxy, finer details ofdust properties and dust-star geometry, and the influences of poorly understood, luminous stellar types and phases. The challenge for the coming years will be to improve both the models and the observational data sets to resolve these uncertainties. The present review will be made available on an interactive, moderated web page (sedfitting.org), where the community can access and change the text. The intention is to expand the text and keep it up to date over the coming years.Comment: 54 pages, 26 figures, Accepted for publication in Astrophysics & Space Scienc

Evidence of Color Coherence Effects in W+jets Events from ppbar Collisions at sqrt(s) = 1.8 TeV

We report the results of a study of color coherence effects in ppbar collisions based on data collected by the D0 detector during the 1994-1995 run of the Fermilab Tevatron Collider, at a center of mass energy sqrt(s) = 1.8 TeV. Initial-to-final state color interference effects are studied by examining particle distribution patterns in events with a W boson and at least one jet. The data are compared to Monte Carlo simulations with different color coherence implementations and to an analytic modified-leading-logarithm perturbative calculation based on the local parton-hadron duality hypothesis.Comment: 13 pages, 6 figures. Submitted to Physics Letters