High performance computing and communications program

A review of the High Performance Computing and Communications (HPCC) program is provided in vugraph format. The goals and objectives of this federal program are as follows: extend U.S. leadership in high performance computing and computer communications; disseminate the technologies to speed innovation and to serve national goals; and spur gains in industrial competitiveness by making high performance computing integral to design and production

A NASA initiative: Software engineering for reliable complex systems

The objective is the development of methods, technology, and skills that will enable NASA to cost-effectively specify, build, and manage reliable software which can evolve and be maintained over an extended period. The need for such software is rooted in the increasing integration of software and computing components into NASA systems. Current NASA Software Engineering expertise was applied toward some of the largest reliable systems including: shuttle launch; ground support; shuttle simulation; minor control; satellite tracking; and scientific data systems. Unfortunately, no theory exists for reliable complex software systems. NASA is seeking to fill this theoretical gap through a number of approaches. One such approach is to conduct research on theoretical foundations for managing complex software systems. It includes: communication models, new and modified paradigms, and life-cycle models. Another approach is research in the theoretical foundations for reliable software development and validation. It focuses upon formal specifications, programming languages, software engineering systems, software reuse, formal verification, and software safety. Further approaches involve benchmarking a NASA software environment, experimentation within the NASA context, evolution of present NASA methodology, and transfer of technology to the space station software support environment

NASA'S information technology activities for the 90's

The Office of Aeronautics, Exploration and Technology (OAET) is completing an extensive assessment of its nearly five hundred million dollars of proposed space technology development work. The budget is divided into four segments which are as follows: (1) the base research and technology program; (2) the Civil Space Technology Initiative (CSTI); (3) the Exploration Technology Program (ETP); and (4) the High Performance Computing Initiative (HPCI). The programs are briefly discussed in the context of Astrotech 21

Information sciences and human factors overview

An overview of program objectives of the Information Sciences and Human Factors Division of NASA's Office of Aeronautics and Space Technology is given in viewgraph form. Information is given on the organizational structure, goals, the research and technology base, telerobotics, systems autonomy in space operations, space sensors, humans in space, space communications, space data systems, transportation vehicle guidance and control, spacecraft control, and major program directions in space

NASA high performance computing and communications program

The National Aeronautics and Space Administration's HPCC program is part of a new Presidential initiative aimed at producing a 1000-fold increase in supercomputing speed and a 100-fold improvement in available communications capability by 1997. As more advanced technologies are developed under the HPCC program, they will be used to solve NASA's 'Grand Challenge' problems, which include improving the design and simulation of advanced aerospace vehicles, allowing people at remote locations to communicate more effectively and share information, increasing scientist's abilities to model the Earth's climate and forecast global environmental trends, and improving the development of advanced spacecraft. NASA's HPCC program is organized into three projects which are unique to the agency's mission: the Computational Aerosciences (CAS) project, the Earth and Space Sciences (ESS) project, and the Remote Exploration and Experimentation (REE) project. An additional project, the Basic Research and Human Resources (BRHR) project exists to promote long term research in computer science and engineering and to increase the pool of trained personnel in a variety of scientific disciplines. This document presents an overview of the objectives and organization of these projects as well as summaries of individual research and development programs within each project

Metastable liquid lamellar structures in binary and ternary mixtures of Lennard-Jones fluids

We have carried out extensive equilibrium molecular dynamics (MD) simulations to investigate the Liquid-Vapor coexistence in partially miscible binary and ternary mixtures of Lennard-Jones (LJ) fluids. We have studied in detail the time evolution of the density profiles and the interfacial properties in a temperature region of the phase diagram where the condensed phase is demixed. The composition of the mixtures are fixed, 50% for the binary mixture and 33.33% for the ternary mixture. The results of the simulations clearly indicate that in the range of temperatures $78 < T < 102 ^{\rm o}$K, --in the scale of argon-- the system evolves towards a metastable alternated liquid-liquid lamellar state in coexistence with its vapor phase. These states can be achieved if the initial configuration is fully disordered, that is, when the particles of the fluids are randomly placed on the sites of an FCC crystal or the system is completely mixed. As temperature decreases these states become very well defined and more stables in time. We find that below $90 ^{\rm o}$K, the alternated liquid-liquid lamellar state remains alive for 80 ns, in the scale of argon, the longest simulation we have carried out. Nonetheless, we believe that in this temperature region these states will be alive for even much longer times.Comment: 18 Latex-RevTex pages including 12 encapsulated postscript figures. Figures with better resolution available upon request. Accepted for publication in Phys. Rev. E Dec. 1st issu

Incidence and Effects of Feeding Intolerance in Trauma Patients

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Clinical Observation Study of Massive Blood Transfusion in a Tertiary Care Hospital in Korea

PURPOSE: Massive blood transfusios are uncommon. The goal of this study was to propose an ideal ratio for the blood component of massive hemorrhage treatment after review of five years of massive transfusion practice, in order to have the best possible clinical outcomes. MATERIALS AND METHODS: We defined a 'massive transfusion' as receiving 10 or more units of red blood cells in one day. A list of patients receiving a massive transfusion from 2004 to 2008 was generated using the electronic medical records. For each case, we calculated the ratio of blood components and examined its relationship to their survival. RESULTS: Three hundred thirty four patients underwent massive transfusion during the five years of the study. The overall seven-day hospital mortality for massive transfusion patients was 26.1%. Factors independently predictive of survival were a fresh-frozen plasma (FFP)/packed red blood cell (pRBC) ratio ≥ 1.1 with an odds ratio (OR) of 1.96 (1.03-3.70), and elective admission with an OR of 2.6 (1.52-4.40). The receiver operation characteristic (ROC) curve suggest that a 1 : 1 : 1 ratio of pRBCs to FFP to platelets is the best ratio for survival. CONCLUSION: Fixing blood-component ratios during active hemorrhage shows improved outcomes. Thus, the hospital blood bank and physician hypothesized that a fixed blood component ratio would help to reduce mortality and decrease utilization of the overall blood componentope

NASA information sciences and human factors program

The FY-90 descriptions of technical accomplishments are contained in seven sections: Automation and Robotics, Communications, Computer Sciences, Controls and Guidance, Data Systems, Human Factors, and Sensor Technology

Ferromagnetism in magnetically doped III-V semiconductors

The origin of ferromagnetism in semimagnetic III-V materials is discussed. The indirect exchange interaction caused by virtual electron excitations from magnetic impurity level in the bandgap to the valence band can explain ferromagnetism in GaAs(Mn) no matter samples are degenerated or not. Formation of ferromagnetic clusters and percolation picture of phase transition describes well all available experimental data and allows to predict the Mn-composition dependence of transition temperature in wurtzite (Ga,In,Al)N epitaxial layers.Comment: 4 pages with 3 figure