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CURSO DE PÓS-GRADUAÇÃO EM ENGENHARIA E TECNOLOGIA ESPACIAIS ÁREA DE CONCENTRAÇÃO EM CIÊNCIA E, França, 2003 #12;2 CURSO DE PÓS-GRADUAÇÃO EM ENGENHARIA E TECNOLOGIA ESPACIAIS ÁREA DE CONCENTRAÇÃO EM para o Mestrado (*) CMS-207-4 Técnicas Experimentais em Ciência dos Materiais I CMS-300-4 Mecânica
CURSO DE PÓS-GRADUAÇÃO EM ENGENHARIA E TECNOLOGIA ESPACIAIS ÁREA DE CONCENTRAÇÃO EM COMBUSTÃO E PROPULSÃO Coordenadora Acadêmica do Curso Evandro Marconi Rocco Coordenador da Área de Concentração David, Doutor, INPE, 2006. #12;CURSO DE ENGENHARIA E TECNOLOGIA ESPACIAIS ÁREA DE CONCENTRAÇÃO EM COMBUSTÃO E
CURSO DE PÓS-GRADUAÇÃO EM ENGENHARIA E TECNOLOGIA ESPACIAIS ÁREA DE CONCENTRAÇÃO EM COMBUSTÃO E PROPULSÃO Coordenador Acadêmico do Curso Evandro Marconi Rocco Coordenador da Área de Concentração David dos Mendonça do IAE/CTA, Univ. Pennsylvania, USA, 1997 #12;CURSO DE ENGENHARIA E TECNOLOGIA ESPACIAIS ÁREA DE
Ps-Graduao em Gerenciamento de Sistemas Espaciais Disciplina Isolada
Pós-Graduação em Gerenciamento de Sistemas Espaciais Disciplina Isolada Documentos a serem apresentados na secretaria do CSE: comprovante de: matricula do candidato em Curso de Pós-Graduação ou de ser Substituído por Declaração que conste data de colação de grau. Em hipótese alguma será aceito aluno que não
CURSO DE PÓS-GRADUAÇÃO EM ENGENHARIA E TECNOLOGIA ESPACIAIS ÁREA DE CONCENTRAÇÃO EM COMBUSTÃO E PROPULSÃO Coordenador Acadêmico do Curso Evandro Marconi Rocco Coordenador da Área de Concentração David dos, USA, 1997 Antonio Osny de Toledo do CTA/IEAV, Doutor, ITA, Brasil, 1996 #12;CURSO DE ENGENHARIA E
Instituto Nacional de Pesquisas Espaciais -Laboratrio Associado de Plasma 1 Project ELISA
Instituto Nacional de Pesquisas Espaciais - Laboratório Associado de Plasma 1 Project ELISAnd Workshop on EQUARS Satellite Project, 29-31 July, 2003, INPE, São José dos Campos, SP, Brazil #12 the energy spectrum of (0.1- 40) keV electrons Scientific Objectives: 1. Electron Precipitation in the South
INSTITUTO NACIONAL DE PESQUISAS ESPACIAIS CONCURSO PÚBLICO PARA PROVIMENTO DE VAGAS EM CARGOS DE NÍVEL SUPERIOR DA CARREIRA DE PESQUISA EM CIÊNCIA E TECNOLOGIA O DIRETOR DO INSTITUTO NACIONAL DE para o Concurso Público para Provimento de Vagas em Cargos de Nível Superior da Carreira de Pesquisa
REGIMENTO DO CURSO DE PÓS-GRADUAÇÃO EM ENGENHARIA E TECNOLOGIA ESPACIAIS, ÁREA DE CONCENTRAÇÂO EM COMBUSTÃO E PROPULSÃO TÍTULO IV DO CORPO DOCENTE Art. 7o O Corpo Docente do Curso é constituído por. Parágrafo 1o Poderão fazer parte do Corpo Docente do Curso, como professores colaboradores, docentes de
João Alberto De Negri
1 INTRODUÇÃO O aumento do comércio internacional nas últimas décadas tem levado a lite- ratura a se desenvolver para explicar o comércio entre os países e acomodar evidências empíricas sobre os determinantes do comércio internacional. Nesse contexto, é particularment e relevante a teoria que busca explicar o comércio intra-indústria com base em economias de escala e diferenciação de produto. De
Numerical Aerodynamic Simulation (NAS)
NASA Technical Reports Server (NTRS)
Peterson, V. L.; Ballhaus, W. F., Jr.; Bailey, F. R.
The history of the Numerical Aerodynamic Simulation Program, which is designed to provide a leading-edge capability to computational aerodynamicists, is traced back to its origin in 1975. Factors motivating its development and examples of solutions to successively refined forms of the governing equations are presented. The NAS Processing System Network and each of its eight subsystems are described in terms of function and initial performance goals. A proposed usage allocation policy is discussed and some initial problems being readied for solution on the NAS system are identified.
National Alcohol Survey (NAS) is designed to assess the trends in drinking practices and problems in the national population, including attitudes, norms, treatment and experiences and adverse consequences. It also studies the effects of public policy on drinking practices (i.e., ...
Storage : DAS / SAN / NAS Dploiement
Collette. Sébastien
CH8 Divers Agenda · Storage : DAS / SAN / NAS · Déploiement · VLAN 802.1Q · Gestion d · Sécurisation de Windows · Sécurisation de UNIX · Qu'est-ce que... Firewall, VPN, IDS/IPS, PKI Storage : DAS, NAS, SAN #12;Storage : DAS, NAS, SAN · Direct Attached Storage · Network Attached Storage · Storage
Curso 4 -Uso de Ferramentas Livres para a Modelagem de Processos e Dinmicas Espaciais (Using Open Tools for Modelling Spatial Processes and Dynamics)
Curso 4 - Uso de Ferramentas Livres para a Modelagem de Processos e Dinâmicas Espaciais (Using Open Natureza: Teórico/Prático (Dois alunos por computador) Resumo: Este curso tem por objetivo fornecer uma no Brasil serão o foco principal do curso. Os exemplos práticos serão desenvolvidos com o apoio das
Observações simultâneas no óptico e infravermelho próximo dos BL Lacs PKS 2005-489 e PKS 2155-304 em diversas escalas de tempo
NASA Astrophysics Data System (ADS)
Dominici, T. P.; Abraham, Z.; Galo, A. L.
A existência de variações rápidas de brilho em alguns blazares é um fenômeno bem comprovado, mas até agora não sabemos ao certo quais são os mecanismos físicos envolvidos. A maior dificuldade é a ausência de observações multibanda simultâneas que poderiam fornecer vínculos aos modelos. Buscando colaborar com a discussão estudamos o comportamento de dois BL Lacs, PKS 2005-489 e PKS 2155-304, em relação à variabilidade em diversas escalas de tempo, de poucos minutos até vários meses, com observações simultâneas em seis bandas espectrais (óptico e infravermelho próximo). Para tanto dois telescópios do LNA foram utilizados em conjunto nas campanhas observacionais realizadas em 2001 e 2002, cujos resultados são apresentados aqui. As duas fontes apresentaram características bastante diferentes, inclusive em relação à existência de variabilidade nos índices espectrais. Particularmente, registramos a primeira detecção de variações em escalas de tempo da ordem de poucos minutos em PKS 2005-489, com evidências da presença de um atraso entre as curvas de luz nas bandas V e R e a variação em R ocorrendo antes (o contrário do esperado no modelo de shock-in-jet). Em PKS 2155-304 detectamos pela primeira vez variabilidade em escalas de tempo de poucos minutos no infravermelho em um AGN. As observações indicam que as variações de brilho em blazares são o resultado da ação de mais de um fenômeno, especialmente em escalas de tempo muito curtas. Alguns cenários físicos são sugeridos para explicar os resultados observacionais.
NAS Applications and Advanced Algorithms
NASA Technical Reports Server (NTRS)
Bailey, David H.; Biswas, Rupak; VanDerWijngaart, Rob; Kutler, Paul (Technical Monitor)
This paper examines the applications most commonly run on the supercomputers at the Numerical Aerospace Simulation (NAS) facility. It analyzes the extent to which such applications are fundamentally oriented to vector computers, and whether or not they can be efficiently implemented on hierarchical memory machines, such as systems with cache memories and highly parallel, distributed memory systems.
The NAS kernel benchmark program
NASA Technical Reports Server (NTRS)
Bailey, D. H.; Barton, J. T.
A collection of benchmark test kernels that measure supercomputer performance has been developed for the use of the NAS (Numerical Aerodynamic Simulation) program at the NASA Ames Research Center. This benchmark program is described in detail and the specific ground rules are given for running the program as a performance test.
NASA Technical Reports Server (NTRS)
Johnson, Charles W.
The vision of the Unmanned Aircraft System (UAS) Integration in the National Airspace System (NAS) Project is "A global transportation system which allows routine access for all classes of UAS." The goal of the UAS Integration in the NAS Project is to "contribute capabilities that reduce technical barriers related to the safety and operational challenges associated with enabling routine UAS access to the NAS." This goal will be accomplished through a two-phased approach based on development of system-level integration of key concepts, technologies and/or procedures, and demonstrations of integrated capabilities in an operationally relevant environment. Phase 1 will take place the first two years of the Project and Phase 2 will take place the following three years. The Phase 1 and 2 technical objectives are: Phase 1: Developing a gap analysis between current state of the art and the Next Generation Air Transportation System (NextGen) UAS Concept of Operations . Validating the key technical areas identified by this Project . Conducting initial modeling, simulation, and flight testing activities . Completing Sub-project Phase 1 deliverables (spectrum requirements, comparative analysis of certification methodologies, etc.) and continue Phase 2 preparation (infrastructure, tools, etc.) Phase 2: Providing regulators with a methodology for developing airworthiness requirements for UAS, and data to support development of certifications standards and regulatory guidance . Providing systems-level, integrated testing of concepts and/or capabilities that address barriers to routine access to the NAS. Through simulation and flight testing, address issues including separation assurance, communications requirements, and human systems integration in operationally relevant environments. The UAS in the NAS Project will demonstrate solutions in specific technology areas, which will address operational/safety issues related to UAS access to the NAS. Since the resource allocation for this Project is limited ($150M over the five years), the focus is on reducing the technical barriers where NASA has unique capabilities. As a result, technical areas, such as Sense and Avoid (SAA) and beyond line of sight command and control will not be addressed. While these are critical barriers to UAS access, currently, there is a great deal of global effort being exercised to address these challenge areas. Instead, specific technology development in areas where there is certainty that NASA can advance the research to high technology readiness levels will be the Project's focus. Specific sub-projects include Separation Assurance, Human Systems Integration, Communications, Certification, and Integrated Test and Evaluation. Each sub-project will transfer technologies to relevant key stakeholders and decision makers through research transition teams, technology forums, or through other analogous means.
The NAS Computational Aerosciences Archive
NASA Technical Reports Server (NTRS)
Miceli, Kristina D.; Globus, Al; Lasinski, T. A. (Technical Monitor)
In order to further the state-of-the-art in computational aerosciences (CAS) technology, researchers must be able to gather and understand existing work in the field. One aspect of this information gathering is studying published work available in scientific journals and conference proceedings. However, current scientific publications are very limited in the type and amount of information that they can disseminate. Information is typically restricted to text, a few images, and a bibliography list. Additional information that might be useful to the researcher, such as additional visual results, referenced papers, and datasets, are not available. New forms of electronic publication, such as the World Wide Web (WWW), limit publication size only by available disk space and data transmission bandwidth, both of which are improving rapidly. The Numerical Aerodynamic Simulation (NAS) Systems Division at NASA Ames Research Center is in the process of creating an archive of CAS information on the WWW. This archive will be based on the large amount of information produced by researchers associated with the NAS facility. The archive will contain technical summaries and reports of research performed on NAS supercomputers, visual results (images, animations, visualization system scripts), datasets, and any other supporting meta-information. This information will be available via the WWW through the NAS homepage, located at http://www.nas.nasa.gov/, fully indexed for searching. The main components of the archive are technical summaries and reports, visual results, and datasets. Technical summaries are gathered every year by researchers who have been allotted resources on NAS supercomputers. These summaries, together with supporting visual results and references, are browsable by interested researchers. Referenced papers made available by researchers can be accessed through hypertext links. Technical reports are in-depth accounts of tools and applications research projects performed by NAS staff members and collaborators. Visual results, which may be available in the form of images, animations, and/or visualization scripts, are generated by researchers with respect to a certain research project, depicting dataset features that were determined important by the investigating researcher. For example, script files for visualization systems (e.g. FAST, PLOT3D, AVS) are provided to create visualizations on the user's local workstation to elucidate the key points of the numerical study. Users can then interact with the data starting where the investigator left off. Datasets are intended to give researchers an opportunity to understand previous work, 'mine' solutions for new information (for example, have you ever read a paper thinking "I wonder what the helicity density looks like?"), compare new techniques with older results, collaborate with remote colleagues, and perform validation. Supporting meta-information associated with the research projects is also important to provide additional context for research projects. This may include information such as the software used in the simulation (e.g. grid generators, flow solvers, visualization). In addition to serving the CAS research community, the information archive will also be helpful to students, visualization system developers and researchers, and management. Students (of any age) can use the data to study fluid dynamics, compare results from different flow solvers, learn about meshing techniques, etc., leading to better informed individuals. For these users it is particularly important that visualization be integrated into dataset archives. Visualization researchers can use dataset archives to test algorithms and techniques, leading to better visualization systems, Management can use the data to figure what is really going on behind the viewgraphs. All users will benefit from fast, easy, and convenient access to CFD datasets. The CAS information archive hopes to serve as a useful resource to those interested in computational sciences. At present, only information that may be di
Mapa Geologico de Venezuela a Escala 1:750,000
Hackley, Paul C.; Urbani, Franco; Karlsen, Alex W.; Garrity, Christopher P.
Se presenta un mapa geologico digital de Venezuela sobre un fondo de relieve sombreado. Los datos geologicos e hidrologicos del norte del rio Orinoco proceden de la digitalizacion de mapas geologicos en papel a escala 1:500.000. Estos datos fueron integrados con el mapa geologico digital del Escudo de Guayana Venezolano, a su vez derivado de hojas en papel a escala 1:500.000. La informacion sobre los tipos de fallas mostrados en el mapa es igual que en las fuentes originales. Los poligonos geologicos fueron atribuidos por edad, litologia y nombre de la unidad siguiendo el Codigo geologico de Venezuela. Se incorporaron revisiones significativas de la geologia de la Cordillera de la Costa a partir de las nuevas hojas integradas a escala 1:25.000. Toda esta informacion geologico-estructural se sobrepuso a una imagen de relieve sombreado, producida por el procesamiento de los datos de radar interferometrico con 90 m (3 arcosegundos) de resolucion espacial obtenidos por la mision topografica de radar del transbordador espacial (SRTM). Las areas de la base de datos del SRTM carentes de informacion fueron llenadas por medio de la interpolacion de los datos de las celdas adyacentes. Para producir la imagen de relieve sombreado se uso una direccion de iluminacion de 315 deg con un angulo de 65 deg sobre el horizonte. La proyeccion usada en el mapa es conica equidistante, con latitudes de 4 y 9 deg norte como paralelos estandar y una longitud de 66 deg al oeste como meridiano central. Los datos en el mapa proceden primordialment de hojas a escala 1:500.000 y el producto esta preparado para una impresion optima en escala 1:750.000. Los usuarios pueden obtener ampliaciones mayores, sin embargo no se garantiza la precision del mapa a escalas mas detalladas. Especialmente en la region de Guayana, al sobreponer los mapas geologicos sobre la reciente imagen SRTM, se notan grandes discrepancias no sistematicas tanto en contactos como en fallas. Esto es debido a que los mapas geologicos de Guayana tienen como base topografica las imagenes de radar de vision lateral (SLAR), con muy control de campo de los a?os 1970's. La correccion de estos desfases esta planificada para el futuro.
Lina Kátia; Mesquita de Oliveira; Creso Franco; Tufi Machado Soares
1. INTRODUÇÃO Usualmente, programas de avaliação em larga escala utilizam uma metodologia de interpretação e construção de escalas de proficiência baseada na Teoria da Resposta ao Item e na análise pedagógica das habilidades avaliadas por meio de itens âncora, selecionados com base na freqüência observada de acertos. Dessa abordagem resultam escalas que associam a cada nível de proficiência um conjunto
Greenhouse policy study from NAS
NASA Astrophysics Data System (ADS)
Maggs, William Ward
The National Academy of Sciences will produce a study for the Environmental Protection Agency on policy responses to global warming. The report is due out before the end of 1990.Dan J. Evans, former U.S. Senator and former Governor of Washington, will chair a panel of the Commission on Science, Engineering, and Public Policy, a body of the councils of the NAS, National Academy of Engineering, and Institute of Medicine. Evans is a registered civil engineer and previously chaired the Pacific Northwest Electric Power and Conservation Planning Council.The 13-person panel includes AGU members Stephen Schneider of the National Center for Atmospheric Research and Robert Frosch, Vice President of Research Laboratores at General Motors Corp., Jessica Mathews, Vice President of the World Resources Institute, and Sir Crispin Tickell, the United Kingdom's Ambassador to the United Nations.
Communication Characteristics in the NAS Parallel Benchmarks
Yuan, Xin
Communication Characteristics in the NAS Parallel Benchmarks Ahmad Faraj Xin Yuan Department-- In this paper, we investigate the communication characteris- tics of the Message Passing Interface (MPI) implementation of the NAS parallel benchmarks and study the effectiveness of com- piled communication for MPI
The optical gain spectra for GaInNAs/GaAs quantum wells are computed using a microscopic laser theory. From these spectra, the peak gain and carrier radiative decay rate as functions of carrier density are determined. These dependences allow the study of the lasing threshold current density of GaInNAs/GaAs quantum well structures.
in college end university programs, and radiochemistry in environmental science, This series of monographsNAs-Ns-3034(Revm) R OF TITANIUM NUCLEAR SCIENCE SERIES National Academy of Sciences one, two, or three randomly selected publications in the NAS-NS series. Additional individual copies
monographs. The Energy Rewarch and Development Administrationhassponsoredthe printingof the seriesNAS-NS-3061 RA OFBISMUTH NUCLEAR SCIENCE SERIES National Academy of Sciences - National Research. Itsmembers represent government, industrial,and universitylaboratoriesin the areas of nuclear chemistry
The NAS Parallel Benchmarks 2.0
David Bailey; Tim Harris; William Saphir; Rob Van Der Wijngaart; Alex Woo; Maurice Yarrow
We describe a set of implementations of the NAS Parallel Benchmarks based on Fortran 77 and the MPI message passing standard. These implementations,which are intended to be run with little or no tuning, approximate the performance a typical user can expect for a portable parallel program on a distributed memory computer. They complement rather than replace the originalNAS Parallel Benchmarks.We
Status and projections of the NAS program
NASA Technical Reports Server (NTRS)
Bailey, Frank R.
NASA's Numerical Aerodynamic Simulation (NAS) Program has completed development of the initial operating configuration of the NAS Processing System Network (NPSN). This is the first milestone in the continuing and pathfinding effort to provide state-of-the-art supercomputing for aeronautics research and development. The NPSN, available to a nation-wide community of remote users, provides a uniform UNIX environment over a network of host computers ranging from the Cray-2 supercomputer to advanced scientific workstations. This system, coupled with a vendor-independent base of common user interface and network software, presents a new paradigm for supercomputing environments. Background leading to the NAS program, its programmatic goals and strategies, technical goals and objectives, and the development activities leading to the current NPSN configuration are presented. Program status, near-term plans, and plans for the next major milestone, the extended operating configuration, are also discussed.
Antimycobacterial Activity and Mechanism of Action of NAS-91?
Gratraud, Paul; Surolia, Namita; Besra, Gurdyal S.; Surolia, Avadhesha; Kremer, Laurent
The antimalarial agents NAS-91 and NAS-21 were found to express potent antimycobacterial activity, NAS-91 being more active than NAS-21. They partially inhibited mycolic acid biosynthesis and profoundly altered oleic acid production. The development of a cell-free assay for ?9-desaturase activity allowed direct demonstration of the inhibition of oleic acid biosynthesis by these compounds. PMID:18086849
Implementation of NAS Parallel Benchmarks in Java
NASA Technical Reports Server (NTRS)
Frumkin, Michael; Schultz, Matthew; Jin, Hao-Qiang; Yan, Jerry
A number of features make Java an attractive but a debatable choice for High Performance Computing (HPC). In order to gauge the applicability of Java to the Computational Fluid Dynamics (CFD) we have implemented NAS Parallel Benchmarks in Java. The performance and scalability of the benchmarks point out the areas where improvement in Java compiler technology and in Java thread implementation would move Java closer to Fortran in the competition for CFD applications.
UAS Integration in the NAS Project - Project Overview
NASA Technical Reports Server (NTRS)
Johnson, Chuck
The goal of the UAS integration in the NAS Project is to contribute capabili1es that reduce technical barriers related to the safety and opera1onal challenges associated with enabling routine UAS access to the NAS.
HPC Symposium, NAS 2008R. L. Winslow Raimond L. Winslow
Winslow, Raimond
HPC Symposium, NAS 2008R. L. Winslow Raimond L. Winslow The Institute for Computational Medicine and Integrative Modeling of Biological Systems #12;HPC Symposium, NAS 2008R. L. Winslow Molecule (Micro Physiology Domain ~ 10-3 Sec #12;HPC Symposium, NAS 2008R. L. Winslow Talk Outline Integrative Modeling
The NAS battery: a multifunction energy storage system
B. Tamyurek; D. K. Nichols; O. Demirci
This paper presents an overview of the first U.S. demonstration of stationary sodium sulfur (NAS) battery energy storage technology hosted by the American electric power (AEP). The NAS batteries are supplied by NGK insulators, Ltd. in Japan. ABB, Inc. of New Berlin, Wisconsin supplied the power conversion system that integrates direct current (DC) from the NAS battery with the alternating
Performance and the NAS Parallel Benchmarks
NASA Technical Reports Server (NTRS)
Bailey, David H.; Lasinski, T. A. (Technical Monitor)
This talk will describe the NAS (National Aerospace Standards) Parallel Benchmarks, which are now widely cited in the high performance computing field as a measure of sustained performance on realistic scientific applications. The latest performance results will be included. It will be shown that significant progress has been made by several systems during the past year or so, with sustained performance on a par with the best conventional systems, and with performance per dollar significantly exceeding the conventional systems. This talk will also describe many of the pitfalls of performance reporting, and will give advice on how to avoid such pitfalls. The overall state of the field of high performance computing will also be discussed.
Factor Structure of the "Escala de Autoeficacia para la Depresion en Adolescentes" (EADA)
ERIC Educational Resources Information Center
Diaz-Santos, Mirella; Cumba-Aviles, Eduardo; Bernal, Guillermo; Rivera-Medina, Carmen
The current concept and measures of self-efficacy for depression in adolescents do not consider developmental and cultural aspects essential to understand and assess this construct in Latino youth. We examined the factor structure of the "Escala de Autoeficacia para la Depresion en Adolescentes" (EADA), a Spanish instrument designed to assess this…
An Implementation Plan for NFS at NASA's NAS Facility
NASA Technical Reports Server (NTRS)
Lam, Terance L.; Kutler, Paul (Technical Monitor)
This document discusses how NASA's NAS can benefit from the Sun Microsystems' Network File System (NFS). A case study is presented to demonstrate the effects of NFS on the NAS supercomputing environment. Potential problems are addressed and an implementation strategy is proposed.
NAS Grid Benchmarks: A Tool for Grid Space Exploration
Michael A. Frumkin; Rob F. Van Der Wijngaart
We present a benchmark suite for computational grids in this paper. It is based on the NAS Parallel Benchmarks (NPB) and is called the NAS Grid Benchmark (NGB). We present NGB as a data flow graph encapsulating an instance of an NPB code in each graph node, which communicates with other nodes by sending\\/receiving initialization data. These nodes may be
NAS-NS-3049(Rev.)' NUCLEAR SCIENCE SERIES
in environmental science. This series of monographs has grown out of the need for compilations of radiochemicalNAS-NS-3049(Rev.)' \\ RA , .---. OF SILICON NUCLEAR SCIENCE SERIES National Academy of Sciences randomly selected publications in the NAS-NS series. Additional individual copies will be sold
Física e Arte nas Estações do Ano
NASA Astrophysics Data System (ADS)
Pessôa Queiroz, Glória; da Conceição Barbosa Lima, Maria; Navarro Vasconcellos das Mercês, Maria
The paper deals with the subject of the Four Seasons, exploring elements of Science and the Art in order to motivate students or public of museums of science and technology to understand it from their current cultural experiences and of old times. Physics joins to Astronomy to explain the phenomenon, while the use of Music and Painting make possible the immersion in the subject in way to many trips to the imagination capable to awake emotions.A proposal didactic is presented and justified for some consensus of the research in the area of teaching-learning of science, since that related to the persistent alternative conceptions concerning the causes of the changes observed at the different times of the year until the qualitative modelling of phenomena that appeals three-dimensional pedagogical models. Such proposal was developed in the activity named " Hiper interesting Talk: The Four Seasons, Science and Art" in the first Sunday of August/2003 in the Museum of Astronomy, MAST. O artigo trata do tema das Estações do Ano, explorando elementos da Ciência e da Arte como forma de motivar estudantes ou público de museus de ciência e tecnologia a compreendê-lo a partir de vivências culturais atuais e de outras épocas. A Física se junta à Astronomia para explicar o fenômeno, enquanto a Música e a Pintura possibilitam a imersão no tema em meio a muitas viagens à imaginação capazes de despertar emoções.Uma proposta didática é apresentada e justificada por consensos das muitas pesquisas na área de ensino-aprendizagem de ciências, desde os que se referem às persistentes concepções alternativas acerca das causas das mudanças observadas nas diferentes épocas do ano até à modelagem qualitativa de fenômenos que recorre a modelos pedagógicos tridimensionais. Tal proposta foi desenvolvida na atividade "Bate papo Hiperinteressante: As Quatro Estações, Ciência e Arte" realizada no primeiro domingo do mês de agosto de 2003 no Museu de Astronomia.
The Need for Vendor Source Code at NAS. Revised
NASA Technical Reports Server (NTRS)
Carter, Russell; Acheson, Steve; Blaylock, Bruce; Brock, David; Cardo, Nick; Ciotti, Bob; Poston, Alan; Wong, Parkson; Chancellor, Marisa K. (Technical Monitor)
The Numerical Aerodynamic Simulation (NAS) Facility has a long standing practice of maintaining buildable source code for installed hardware. There are two reasons for this: NAS's designated pathfinding role, and the need to maintain a smoothly running operational capacity given the widely diversified nature of the vendor installations. NAS has a need to maintain support capabilities when vendors are not able; diagnose and remedy hardware or software problems where applicable; and to support ongoing system software development activities whether or not the relevant vendors feel support is justified. This note provides an informal history of these activities at NAS, and brings together the general principles that drive the requirement that systems integrated into the NAS environment run binaries built from source code, onsite.
UAS Integration in the NAS Project - FY 14 Annual Review
NASA Technical Reports Server (NTRS)
Grindle, Laurie; Randall, Debra; Hackenberg, Davis
This briefing gives insight into the research activities and efforts being executed in order to integrate unmanned aircraft systems into the national airspace system. This briefing is to inform others of the UAS-NAS Projects progress and future directions.
NAS - Supercomputing master tool for aeronautics. [Numerical Aerodynamic Simulation
NASA Technical Reports Server (NTRS)
Bailey, F. R.
Features, performance objectives and applications planned for the NASA National Aerodynamics Simulator (NAS) are outlined. NAS was conceived in the 1970s as a means to performing numerical aerodynamic simulations beyond the scope of wind tunnel testing for high-speed flight. Present supercomputers cannot deal with problems exhibiting strongly coupled viscous effects, which are being increasingly more accurately represented by approximations to the full Navier-Stokes equations. Located at the NASA-Ames Center, the NAS will by 1990 comprise a distributed computer network capable of a 4 Gflop computing rate and have a memory capacity of 1 billion 64-bit words. Remote access to the system through UNIX-based microcomputers will be available through land lines and satellite links. New supercomputers will be tested on the system without disturbing ongoing work. The core machine will be a Cray-2 with a 2 Gflop rate.
Advanced Intermediate-Temperature Na-S Battery
Lu, Xiaochuan; Kirby, Brent W.; Xu, Wu; Li, Guosheng; Kim, Jin Yong; Lemmon, John P.; Sprenkle, Vincent L.; Yang, Zhenguo (Gary) [Gary
In this study, we reported an intermediate-temperature (~150°C) sodium-sulfur (Na-S) battery. With a reduced operating temperature, this novel battery can potentially reduce the cost and safety issues associated with the conventional high-temperature (300~350°C) Na-S battery. A dense ?"-Al2O3 solid membrane and tetraglyme were utilized as the electrolyte separator and catholyte solvent in this battery. Solubility tests indicated that cathode mixture of Na2S4 and S exhibited extremely high solubility in tetraglyme (e.g., > 4.1 M for Na2S4 + 4 S). CV scans of Na2S4 in tetraglyme revealed two pairs of redox couples with peaks at around 2.22 and 1.75 V, corresponding to the redox reactions of polysulfide species. The discharge/charge profiles of the Na-S battery showed a slope region and a plateau, indicating multiple steps and cell reactions. In-situ Raman measurements during battery operation suggested that polysulfide species were formed in the sequence of Na2S5 + S ? Na2S5 + Na2S4? Na2S4 + Na2S2 during discharge and in a reverse order during charge. This battery showed dramatic improvement in rate capacity and cycling stability over room-temperature Na-S batteries, which makes it attractive for renewable energy integration and other grid related applications.
Evaluating the Information Power Grid Using the NAS Grid Benchmarks
Rob F. Van Der Wijngaart; Michael A. Frumkin
The NAS Grid Benchmarks (NGB) are a collection of synthetic distributed applications designed to rate the per- formance and functionality of computational grids. We compare several implementations of the NGB to deter- mine programmability and efficiency of NASA's Informa- tion Power Grid (IPG), whose services are mostly based on the Globus Toolkit. We report on the overheads involved in porting
Unstructured Adaptive (UA) NAS Parallel Benchmark. Version 1.0
NASA Technical Reports Server (NTRS)
Feng, Huiyu; VanderWijngaart, Rob; Biswas, Rupak; Mavriplis, Catherine
We present a complete specification of a new benchmark for measuring the performance of modern computer systems when solving scientific problems featuring irregular, dynamic memory accesses. It complements the existing NAS Parallel Benchmark suite. The benchmark involves the solution of a stylized heat transfer problem in a cubic domain, discretized on an adaptively refined, unstructured mesh.
NAS-NS-3026(Rev.) NUCLEAR SCIENCE SERIES
in environmental science. This series of monographs has grown out of the need for compilations of radiochemicalNAS-NS-3026(Rev.) R OF MERCURY NUCLEAR SCIENCE SERIES National Academy of Sciences-NS series. Additional individual copies will be sold in increments of three for $3.00. Available from
Análisis factorial exploratorio y propiedades psicométricas de la Escala de Creencias y Actitudes hacia la hipnosis-cliente
Antonio Capafons; Ana Alarcón; Sonia Cabañas; Begoña Espejo
Las actitudes inadecuadas y las creencias erróneas hacia la hipnosis influyen en las respuestas a las su- gestiones hipnóticas. Especialmente afectan al resultado que se obtiene en intervenciones que adjun- ten hipnosis. La escala evalúa las creencias erróneas más frecuentes hacia la hipnosis y las actitudes negativas derivadas de ellas. Los análisis factoriales exploratorios (N= 761), han generado seis facto-
Como a Petrobras Biocombustíveis pode Engajar Agricultores de Pequena Escala Enquanto Promove a Sustentabilidade do Programa de Biodiesel Brasileiro?
Clovis Zapata; Diego Vazquez-Brust; José Plaza-Úbeda
A nossa pesquisa indica que a Petrobras Biocombustíveis pode ajudar a aliviar a pobreza entre os agricultores familiares de pequena escala, reforçando a integração das partes interessadas no programa brasileiro de biodiesel. Isso corrobora diversos estudos que demonstram a importância das redes compostas pelas partes interessadas (Rowley, 1997; Roloff, 2008), que podem ser particularmente importantes nos programas que visam integrar
NAS Grid Benchmarks: A Tool for Grid Space Exploration
NASA Technical Reports Server (NTRS)
Frumkin, Michael; VanderWijngaart, Rob F.; Biegel, Bryan (Technical Monitor)
We present an approach for benchmarking services provided by computational Grids. It is based on the NAS Parallel Benchmarks (NPB) and is called NAS Grid Benchmark (NGB) in this paper. We present NGB as a data flow graph encapsulating an instance of an NPB code in each graph node, which communicates with other nodes by sending/receiving initialization data. These nodes may be mapped to the same or different Grid machines. Like NPB, NGB will specify several different classes (problem sizes). NGB also specifies the generic Grid services sufficient for running the bench-mark. The implementor has the freedom to choose any specific Grid environment. However, we describe a reference implementation in Java, and present some scenarios for using NGB.
Implementation of the NAS Parallel Benchmarks in Java
NASA Technical Reports Server (NTRS)
Frumkin, Michael A.; Schultz, Matthew; Jin, Haoqiang; Yan, Jerry; Biegel, Bryan (Technical Monitor)
Several features make Java an attractive choice for High Performance Computing (HPC). In order to gauge the applicability of Java to Computational Fluid Dynamics (CFD), we have implemented the NAS (NASA Advanced Supercomputing) Parallel Benchmarks in Java. The performance and scalability of the benchmarks point out the areas where improvement in Java compiler technology and in Java thread implementation would position Java closer to Fortran in the competition for CFD applications.
Performance and Scalability of the NAS Parallel Benchmarks in Java
NASA Technical Reports Server (NTRS)
Frumkin, Michael A.; Schultz, Matthew; Jin, Haoqiang; Yan, Jerry; Biegel, Bryan A. (Technical Monitor)
Several features make Java an attractive choice for scientific applications. In order to gauge the applicability of Java to Computational Fluid Dynamics (CFD), we have implemented the NAS (NASA Advanced Supercomputing) Parallel Benchmarks in Java. The performance and scalability of the benchmarks point out the areas where improvement in Java compiler technology and in Java thread implementation would position Java closer to Fortran in the competition for scientific applications.
------..--------- !546.8 L472ra .c.8 THE RADIOCHEMISTRY OF IRIDIUM-- NAS-NS 3045 +- -:, G. W The Rctdiochemistry of Iridium #12;COMNll~EE ON. NUCLEAR SCIENCE L.F. CURTffS, CM~ " ROBLEY D.EVAiil%Vk8 Ckzi;c-TRY The Radiochemistry of Iridium G. W. LEDDI~ W Ridge Ndioml Lduwulwy Ckz&Ridge, T-&?See Chb3ber
Evaluating the Information Power Grid using the NAS Grid Benchmarks
NASA Technical Reports Server (NTRS)
VanderWijngaartm Rob F.; Frumkin, Michael A.
The NAS Grid Benchmarks (NGB) are a collection of synthetic distributed applications designed to rate the performance and functionality of computational grids. We compare several implementations of the NGB to determine programmability and efficiency of NASA's Information Power Grid (IPG), whose services are mostly based on the Globus Toolkit. We report on the overheads involved in porting existing NGB reference implementations to the IPG. No changes were made to the component tasks of the NGB can still be improved.
[Psychometric properties of the Escala de Autoeficacia para el Afrontamiento del Estrés (EAEAE)].
Godoy Izquierdo, Débora; Godoy García, Juan F; López-Chicheri García, Isabel; Martínez Delgado, Antonio; Gutiérrez Jiménez, Susana; Vázquez Vázquez, Luisa
This paper presents the theoretical construct of
NAS Requirements Checklist for Job Queuing/Scheduling Software
NASA Technical Reports Server (NTRS)
Jones, James Patton
The increasing reliability of parallel systems and clusters of computers has resulted in these systems becoming more attractive for true production workloads. Today, the primary obstacle to production use of clusters of computers is the lack of a functional and robust Job Management System for parallel applications. This document provides a checklist of NAS requirements for job queuing and scheduling in order to make most efficient use of parallel systems and clusters for parallel applications. Future requirements are also identified to assist software vendors with design planning.
High electron mobility in Ga(In)NAs films grown by molecular beam epitaxy
Miyashita, Naoya; Ahsan, Nazmul; Monirul Islam, Muhammad; Okada, Yoshitaka [Research Center for Advanced Science and Technology (RCAST), The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8904 (Japan); Inagaki, Makoto [Toyota Technological Institute, 2-12-1 Hisakata, Tempaku-ku, Nagoya 468-8511, Aichi (Japan); Yamaguchi, Masafumi [Research Center for Advanced Science and Technology (RCAST), The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8904 (Japan); Toyota Technological Institute, 2-12-1 Hisakata, Tempaku-ku, Nagoya 468-8511, Aichi (Japan)
We report the highest mobility values above 2000 cm{sup 2}/Vs in Si doped GaNAs film grown by molecular beam epitaxy. To understand the feature of the origin which limits the electron mobility in GaNAs, temperature dependences of mobility were measured for high mobility GaNAs and referential low mobility GaInNAs. Temperature dependent mobility for high mobility GaNAs is similar to the GaAs case, while that for low mobility GaInNAs shows large decrease in lower temperature region. The electron mobility of high quality GaNAs can be explained by intrinsic limiting factor of random alloy scattering and extrinsic factor of ionized impurity scattering.
Remotely Operated Aircraft (ROA) Impact on the National Airspace System (NAS) Work Package: Automation Impacts of ROA's in the NAS
NASA Technical Reports Server (NTRS)
The purpose of this document is to analyze the impact of Remotely Operated Aircraft (ROA) operations on current and planned Air Traffic Control (ATC) automation systems in the En Route, Terminal, and Traffic Flow Management domains. The operational aspects of ROA flight, while similar, are not entirely identical to their manned counterparts and may not have been considered within the time-horizons of the automation tools. This analysis was performed to determine if flight characteristics of ROAs would be compatible with current and future NAS automation tools. Improvements to existing systems / processes are recommended that would give Air Traffic Controllers an indication that a particular aircraft is an ROA and modifications to IFR flight plan processing algorithms and / or designation of airspace where an ROA will be operating for long periods of time.
GaInNAsSb Solar Cells Grown by Molecular Beam Epitaxy
David Jackrel; Aaron Ptak; Seth Bank; Homan Yuen; Mark Wistey; Daniel Friedman; Sarah Kurtz; James S. Harris
The first GaInNAsSb solar cells are reported. The dilute nitride antimonide material, grown by molecular beam epitaxy, has a bandgap of 0.92 eV and maintains excellent carrier collection efficiency. Internal quantum efficiency of nearly 80% at maximum is obtained in the narrow bandgap GaInNAsSb cells. The short-circuit current density produced by the GaInNAsSb cells underneath a GaAs sub-cell in a
Spin Lifetimes in annealed GaInNAs epilayers
NASA Astrophysics Data System (ADS)
Tsai, Yutsung; Barman, Biplob; Scrace, Thomas; Petrou, Athos; Fukuda, Miwa; Sellers, Ian; Leroux, Mathieu; Khalfioui, Mohamed; Suny At Buffalo Collaboration; University Of Oklahoma Collaboration; Crhea-Cnrs Collaboration
We have carried out Hanle measurements of the electron spin lifetime TSin optically pumped annealed GaInNAs epilayers (undoped and p-type doped). The samples were placed in a 7T optical magnet cryostat with the magnetic field applied in the epilayer plane. The emitted light was collected along the normal to the epilayers. The PL was excited using the 1064 nm line from a Nd:YAG laser which gives a polarization P = 5% at B =0. The transverse magnetic field results in a reduction of P, from which we determine TS. At T = 50 K, the electron spin lifetime TSwas measured to be 15 ps. As the sample temperature increases, TSdecreases (TS = 7 ps at T = 150 K). Our Hanle results are in agreement with the TSvalues measured by Lombez et al. using time-resolved photoluminescence spectroscopy. The observed sharp reduction in TSin annealed samples is interpreted as due to the D'yakonov-Perel' spin relaxation mechanism. In annealed samples the momentum relaxation time increases, resulting in a reduction of TS The authors acknowledge support through the state of Oklahoma OARs program Grant No. 12.2-040.
Performance Characteristics of the Multi-Zone NAS Parallel Benchmarks
NASA Technical Reports Server (NTRS)
Jin, Haoqiang; VanderWijngaart, Rob F.
We describe a new suite of computational benchmarks that models applications featuring multiple levels of parallelism. Such parallelism is often available in realistic flow computations on systems of grids, but had not previously been captured in bench-marks. The new suite, named NPB Multi-Zone, is extended from the NAS Parallel Benchmarks suite, and involves solving the application benchmarks LU, BT and SP on collections of loosely coupled discretization meshes. The solutions on the meshes are updated independently, but after each time step they exchange boundary value information. This strategy provides relatively easily exploitable coarse-grain parallelism between meshes. Three reference implementations are available: one serial, one hybrid using the Message Passing Interface (MPI) and OpenMP, and another hybrid using a shared memory multi-level programming model (SMP+OpenMP). We examine the effectiveness of hybrid parallelization paradigms in these implementations on three different parallel computers. We also use an empirical formula to investigate the performance characteristics of the multi-zone benchmarks.
The NAS and The Histopathologic Diagnosis in NAFLD: Distinct Clinicopathologic Meanings
Brunt, Elizabeth M.; Kleiner, David E.; Wilson, Laura A.; Belt, Patricia; Neuschwander-Tetri, Brent A.
The diagnosis of nonalcoholic steatohepatitis (NASH) is defined by the presence and pattern of specific histological abnormalities on liver biopsy. A separate system of scoring the features of nonalcoholic fatty liver disease (NA) called the NAFLD Activity Score (NAS) was developed as a tool to measure changes in NAFLD during therapeutic trials. However, some studies have used threshold values of the NAS, specifically NAS ? 5, as a surrogate for the histologic diagnosis of NASH. To evaluate whether this unintended use of the NAS is valid, biopsy and clinical data from the 976 adults in NASH CRN studies were reviewed. Biopsies were evaluated centrally by the NASH CRN Pathology Committee. Definite steatohepatitis (SH) was diagnosed in 58.1%, borderline SH in 19.5% and "not SH" in 22%. The NAS was ? 5 in 50% and ? 4 in 49%; in this cohort only 75% of biopsies with definite SH had a NAS ? 5, while 28% of borderline SH and 7% of "not SH" biopsies had NAS ? 5. Of biopsies with a NAS ? 5, 86% had SH and 3% "not SH". NAS ? 4 did not indicate benign histology; 29% had SH and only 42% had "not SH". Higher values of the NAS were associated with higher levels of ALT and AST, while the diagnosis of SH was associated with features of the metabolic syndrome. Conclusions The diagnosis of definite SH or the absence of SH based on evaluation of patterns as well as individual lesions on liver biopsies does not always correlate with threshold values of the semiquantitative NAS. Clinical trials and observational studies should take these different performance characteristics into account. PMID:21319198
The NAS EarlyBird Programme: Partnership with Parents in Early Intervention.
ERIC Educational Resources Information Center
Shields, Jane
This article describes the development of an autism-specific three-month parent education program by Britain's National Autistic Society (NAS). The NAS EarlyBird Programme emphasizes partnerships with parents and uses weekly group training sessions and individualized home visits to teach parents about autism, social communication, and prevention…
Auger recombination rates in dilute-As GaNAs semiconductor
NASA Astrophysics Data System (ADS)
Tan, Chee-Keong; Tansu, Nelson
The evaluation of Auger recombination process for dilute-As GaNAs alloy is presented. Our analysis indicates the suppression of interband Auger recombination mechanism in dilute-As GaNAs alloy in the green spectral regime. The interband Auger coefficient in dilute-As GaNAs alloy is shown as two orders of magnitude lower than that of its corresponding intraband Auger rate. Our results confirm that the second conduction band has a negligible effect on the interband Auger process in dilute-As GaNAs alloy due to the non-resonant condition of the process. Our findings show the importance of dilute-As GaNAs as an alternative visible material with low Auger recombination rates.
NasFED proteins mediate assimilatory nitrate and nitrite transport in Klebsiella oxytoca (pneumoniae) M5al.
Wu, Q; Stewart, V
Klebsiella oxytoca can use nitrate and nitrite as sole nitrogen sources. The enzymes required for nitrate and nitrite assimilation are encoded by the nasFEDCBA operon. We report here the complete nasFED sequence. Sequence comparisons indicate that the nasFED genes encode components of a conventional periplasmic binding protein-dependent transport system consisting of a periplasmic binding protein (NasF), a homodimeric intrinsic membrane protein (NasE), and a homodimeric ATP-binding cassette (ABC) protein (NasD). The NasF protein and the related NrtA and CmpA proteins of cyanobacteria contain leader (signal) sequences with the double-arginine motif that is hypothesized to direct prefolded proteins to an alternate protein export pathway. The NasE protein and the related NrtB and CmpB proteins of cyanobacteria contain unusual variants of the EAA loop sequence that defines membrane-intrinsic proteins of ABC transporters. To characterize nitrate and nitrite transport, we constructed in-frame nonpolar deletions of the chromosomal nasFED genes. Growth tests coupled with nitrate and nitrite uptake assays revealed that the nasFED genes are essential for nitrate transport and participate in nitrite transport as well. Interestingly, the delta nasF strain exhibited leaky phenotypes, particularly at elevated nitrate concentrations, suggesting that the NasED proteins are not fully dependent on the NasF protein. PMID:9495773
1.15?Å resolution structure of the proteasome-assembly chaperone Nas2 PDZ domain
Singh, Chingakham R.; Lovell, Scott; Mehzabeen, Nurjahan; Chowdhury, Wasimul Q.; Geanes, Eric S.; Battaile, Kevin P.; Roelofs, Jeroen
PDZ domain Chingakham R. Singh,a Scott Lovell,b Nurjahan Mehzabeen,b Wasimul Q. Chowdhury,a Eric S. Geanes,a Kevin P. Battailec and Jeroen Roelofsa* aDivision of Biology, Kansas State University, 338 Ackert Hall, Manhattan, KS 66506, USA, b... substantial structural insights. However, no structural data for Nas2, or the human ortholog p27/PSMD9, have been published to date. Binding studies between Nas2 and Rpt5 have shown that deletion of the C-terminal residue of Rpt5 did not impact Nas2 binding...
78 FR 46497 - Amendment of Class D and E Airspace, and Establishment of Class E Airspace; Oceana NAS, VA
Federal Register 2010, 2011, 2012, 2013, 2014
...Tower at Oceana NAS (Apollo Soucek Field) now operating...This action enhances the safety and airspace management...coordinates of Oceana NAS (Apollo Soucek Field) and NALF...necessary to ensure the safety of aircraft and the efficient...airspace at Oceana NAS (Apollo Soucek Field),...
76 FR 1511 - Amendment of Class D Airspace; Fort Worth NAS JRB (Carswell Field), TX
Federal Register 2010, 2011, 2012, 2013, 2014
...TRANSPORTATION Federal Aviation Administration 14 CFR...TX AGENCY: Federal Aviation Administration (FAA...within the Fort Worth Naval Air Station (NAS) JRB...71.1 of the Federal Aviation Administration Order...Amended] Fort Worth Naval Air Station JRB...
ESTERÓIDES ANABOLiCOS ANDROGÊNICOS: USO E ABUSO NAS ACADEMIAS DE MUSCULAÇAO
Victor Hugo Pereira Franco; Estélio Henriq; Martin Dantas; João Carlos; Bouzas Marins; Jefferson da Silva Novaes
i almejados pelo grupo praticante de rnusculaçâo. Portanto, torna-se primordial que os profissionais de Educação Física que atuam nas\\/ i academias de musculacao sernpre eçtejain atualizados sobre esse tema ; 'i 1
Unmanned Aircraft Systems (UAS) Integration in the National Airspace System (NAS) Project Subcommittee Final
NASA Technical Reports Server (NTRS)
Johnson, Chuck; Griner, James H.; Hayhurst, Kelly J.; Shively, Robert J.; Consiglio, Maria; Muller, Eric; Murphy, James; Kim, Sam
UAS Integration in the NAS Project overview with details from each of the subprojects. Subprojects include: Communications, Certification, Integrated Test and Evaluation, Human Systems Integration, and Separation Assurance/Sense and Avoid Interoperability.
Low temperature grown GaNAsSb: A promising material for photoconductive switch application
Tan, K. H.; Yoon, S. F.; Wicaksono, S.; Loke, W. K.; Li, D. S. [School of Electrical and Electronic Engineering, Nanyang Technological University, Nanyang Avenue, Singapore 639798 (Singapore)] [School of Electrical and Electronic Engineering, Nanyang Technological University, Nanyang Avenue, Singapore 639798 (Singapore); Saadsaoud, N.; Tripon-Canseliet, C. [Laboratoire d'Electronique et Electromagnétisme, Pierre and Marie Curie University, 4 Place Jussieu, 75005 Paris (France)] [Laboratoire d'Electronique et Electromagnétisme, Pierre and Marie Curie University, 4 Place Jussieu, 75005 Paris (France); Lampin, J. F.; Decoster, D. [Institute of Electronics, Microelectronics and Nanotechnology (IEMN), UMR CNRS 8520, Universite des Sciences et Technologies de Lille, BP 60069, 59652 Villeneuve d'Ascq Cedex (France)] [Institute of Electronics, Microelectronics and Nanotechnology (IEMN), UMR CNRS 8520, Universite des Sciences et Technologies de Lille, BP 60069, 59652 Villeneuve d'Ascq Cedex (France); Chazelas, J. [Thales Airborne Systems, 2 Avenue Gay Lussac, 78852 Elancourt (France)] [Thales Airborne Systems, 2 Avenue Gay Lussac, 78852 Elancourt (France)
We report a photoconductive switch using low temperature grown GaNAsSb as the active material. The GaNAsSb layer was grown at 200 °C by molecular beam epitaxy in conjunction with a radio frequency plasma-assisted nitrogen source and a valved antimony cracker source. The low temperature growth of the GaNAsSb layer increased the dark resistivity of the switch and shortened the carrier lifetime. The switch exhibited a dark resistivity of 10{sup 7} ? cm, a photo-absorption of up to 2.1 ?m, and a carrier lifetime of ?1.3 ps. These results strongly support the suitability of low temperature grown GaNAsSb in the photoconductive switch application.
GaInNAs Junctions for Next-Generation Concentrators: Progress and Prospects
Friedman, D. J.; Ptak, A. J.; Kurtz, S. R.; Geisz, J. F.; Kiehl, J.
We discuss progress in the development of GaInNAs junctions for application in next-generation multijunction concentrator cells. A significant development is the demonstration of near-100% internal quantum efficiencies in junctions grown by molecular-beam epitaxy. Testing at high currents validates the compatibility of these devices with concentrator operation. The efficiencies of several next-generation multijunction structures incorporating these state-of-the-art GaInNAs junctions are projected.
GaInNAs Junctions for Next-Generation Concentrators: Progress and Prospects
D. J. Friedman; A. J. Ptak; S. R. Kurtz; J. F. Geisz; J. Kiehl
We discuss progress in the development of GaInNAs junctions for application in next-generation multijunction concentrator cells. A significant development is the demonstration of near-100% internal quantum efficiencies in junctions grown by molecular-beam epitaxy. Testing at high currents validates the compatibility of these devices with concentrator operation. The efficiencies of several next-generation multijunction structures incorporating these state-of-the-art GaInNAs junctions are projected.
GaInNAs for multi-junction tandem solar cells
Akira Ohmae; Yukiko Shimizu; Yoshitaka Okada
We have investigated the effect of atomic H irradiation on the growth of GaInNAs\\/GaAs films in hydrogen-assisted RF-molecular beam epitaxy (RF-MBE) from the viewpoint of growth dynamics and material quality. The crystal quality of GaInNAs films was characterized by using X-ray diffraction (XRD) and photoluminescence (PL), and the surface morphology was characterized by using atomic force microscope (AFM). The atomic
870 IEEE JOURNAL OF QUANTUM ELECTRONICS, VOL. 47, NO. 6, JUNE 2011 Optical Gain in GaInNAs and GaInNAsSb
Gilchrist, James F.
in structures at shorter wavelength. However, there is a large non- radiative current in GaInNAsSb and achieving radiative recombination current due in part to its low photon energy and also to differences in conduction further reductions in the non-radiative current is the major challenge in taking advantage of the good
Hydrazine N Source for Growth of GaInNAs for Solar Cells
Friedman, D. J.; Geisz, G. F.; Kurtz, S. R.; Norman, A. G. (National Renewable Energy Laboratory); Yeh, Y. C. M. (TECSTAR, Inc.)
We evaluate hydrazine (Hy) as a nitrogen precursor source for the growth of GaNAs and GaInNAs for application in 1-eV solar cells lattice-matched to GaAs, and compare it to the more commonly used dimethylhydrazine (DMHy). The incorporation efficiency of N into the GaNAs alloy is found to be one to two orders of magnitude higher with Hy than with DMHy. This high N incorporation makes convenient the growth of GaNAs at higher growth temperatures, Tg=650 C, and arsine flows, AsH3/III=44, than are generally possible with the use of DMHy. GaInNAs and GaNAs solar cells are grown under these growth conditions and compared to a GaAs cell grown under the same conditions to determine the extent to which the poor minority-carrier properties routinely observed for the N-containing material can be attributed to the growth conditions. Finally, the background carrier concentrations for Hy- and DMHy-grown material are compared, and little difference is found between the two sources..
Selective area growth of GaInNAs/GaAs by MOVPE
NASA Astrophysics Data System (ADS)
Olsson, F.; Mion, G.; Sun, Y. T.; Sundgren, P.; Baskar, K.; Armani, N.; Hammar, M.; Lourdudoss, S.
Selective area growth (SAG) of GaInNAs/GaAs systems has been studied by metalorganic vapor-phase epitaxy (MOVPE) for the first time. This also includes a comparative study of SAG of the GaInAs/GaAs. The patterns consisted of various filling factors ( F). The band gap changes and the growth morphology have been investigated. A red-shift observed for SAG GaInAs is ?100 nm with respect to the planar GaInAs which can be attributed to both In enrichment and quantum well (QW) thickness enhancement. Selectively grown GaInNAs structures exhibit a maximum wavelength of 1.3 ?m, corresponding to a red-shift of ?80 nm with respect to the planar GaInNAs. Atomic force microscopy (AFM) scans reveal a three-dimensional growth behaviour for SAG GaInNAs unlike SAG GaInAs. This can be related to a certain amount of phase separation or strain that are often the signatures of N incorporation. The cathodoluminescence (CL) intensities (spectral line width) for SAG GaInNAs are larger (smaller) than those for SAG GaInAs at low F's but smaller (larger) at high F's. This indicates that at low F's, GaInAs has degraded due to very high strain but certain amount of strain compensation occurs in GaInNAs.
The NAS Alert System: a look at the first eight years
Fuller, Pam; Neilson, Matt; Huge, Dane H.
The U.S. Geological Survey's Nonindigenous Aquatic Species (NAS) database program (http://nas.er.usgs.gov) tracks the distribution of introduced aquatic organisms across the United States. Awareness of, and timely response to, novel species introductions by those involved in nonindigenous aquatic species management and research requires a framework for rapid dissemination of occurrence data as it is incorporated into the NAS database. In May 2004, the NAS program developed an alert system to notify registered users of new introductions as part of a national early detection/rapid response system. This article summarizes information on system users and dispatched alerts from the system's inception through the end of 2011. The NAS alert system has registered over 1,700 users, with approximately 800 current subscribers. A total of 1,189 alerts had been transmitted through 2011. More alerts were sent for Florida (134 alerts) than for any other state. Fishes comprise the largest taxonomic group of alerts (440), with mollusks, plants, and crustaceans each containing over 100 alerts. Most alerts were for organisms that were intentionally released (414 alerts), with shipping, escape from captivity, and hitchhiking also representing major vectors. To explore the archive of sent alerts and to register, the search and signup page for the alert system can be found online at http://nas.er.usgs.gov/AlertSystem/default.aspx.
Identification and structure of the nasR gene encoding a nitrate- and nitrite-responsive positive regulator of nasFEDCBA (nitrate assimilation) operon expression in Klebsiella pneumoniae M5al.
Goldman, B S; Lin, J T; Stewart, V
Klebsiella pneumoniae can use nitrate and nitrite as sole nitrogen sources through the nitrate assimilatory pathway. The structural genes for assimilatory nitrate and nitrite reductases together with genes necessary for nitrate transport form an operon, nasFEDCBA. Expression of the nasF operon is regulated both by general nitrogen control and also by nitrate or nitrite induction. We have identified a gene, nasR, that is necessary for nitrate and nitrite induction. The nasR gene, located immediately upstream of the nasFEDCBA operon, encodes a 44-kDa protein. The NasR protein shares carboxyl-terminal sequence similarity with the AmiR protein of Pseudomonas aeruginosa, the positive regulator of amiE (aliphatic amidase) gene expression. In addition, we present evidence that the nasF operon is not autogenously regulated. Images PMID:8051020
First-principles study on structure stabilities of ?-S and Na-S battery systems
NASA Astrophysics Data System (ADS)
Momida, Hiroyoshi; Oguchi, Tamio
To understand microscopic mechanisms of charge and discharge reactions in Na-S batteries, there has been increasing needs to study fundamental atomic and electronic structures of elemental S as well as that of Na-S phases. The most stable form of S is known to be an orthorhombic ?-S crystal at ambient temperature and pressure, and ?-S consists of puckered S8 rings which crystallize in space group Fddd . In this study, the crystal structure of ?-S is examined by using first-principles calculations with and without the van der Waals interaction corrections of Grimme's method, and results clearly show that the van der Waals interactions between the S8 rings have crucial roles on cohesion of ?-S. We also study structure stabilities of Na2S, NaS, NaS2, and Na2S5 phases with reported crystal structures. Using calculated total energies of the crystal structure models, we estimate discharge voltages assuming discharge reactions from 2Na+ xS -->Na2Sx, and discharge reactions in Na/S battery systems are discussed by comparing with experimental results. This work was partially supported by Elements Strategy Initiative for Catalysts and Batteries (ESICB) of Ministry of Education, Culture, Sports, Science, and Technology (MEXT), Japan.
Epitaxial growth and picosecond carrier dynamics of GaInAs/GaInNAs superlattices
Martin, M.; Mangeney, J. [Institut d'Electronique Fondamentale, Universite Paris-Sud XI, UMR 8622 CNRS, 91405 Orsay (France); Travers, L.; Harmand, J. C.; Mauguin, O.; Patriarche, G. [CNRS/LPN, Laboratoire de Photonique et de Nanostructures, 91 460 Marcoussis (France); Minot, C. [CNRS/LPN, Laboratoire de Photonique et de Nanostructures, 91 460 Marcoussis (France); Institut Telecom/Telecom ParisTech, 46 rue Barrault, 75 634 Paris Cedex 13 (France)
We study GaInAs/GaInNAs superlattice structures grown on InP substrate as potential candidates for photoconductive terahertz devices or saturable absorbers working at 1.55 {mu}m wavelength. The N-rich GaInNAs layers are flat, with no three-dimensional islanding, and act as trapping layers where carriers can recombine rapidly. The carrier lifetime in GaInAs/GaInNAs superlattice was measured for various growth parameters using time-resolved differential transmission experiments at 1.55 {mu}m wavelength. The carrier lifetime is found to depend strongly on N content and can be reduced down to 3.8 ps for samples with 14% of N. The mechanisms involved in the capture process of photocarriers are discussed.
Surface morphology and localised states of GaInNAs single quantum wells grown by MOVPE
NASA Astrophysics Data System (ADS)
Baskar, K.; Sundgren, P.; Douheret, O.; Landgren, G.
GaInNAs/GaAs single quantum wells (QWs) have been grown by metalorganic vapour phase epitaxy (MOVPE). The surface morphology has been studied by atomic force microscopy (AFM). The density of pits observed on the surface of QW structures was found to depend on the growth temperature and dimethylhydrazine (DMHy) flow. Cross-sectional AFM image showed the presence of defects at the interface of GaInNAs/GaAs. The low temperature photoluminescence characteristics of the QWs as a function of growth temperature, DMHy flow and density of surface pits have been discussed. The origin of pit formation is addressed based on the pyrolysis products present during the growth of QWs. The results suggest that higher growth temperature maybe desirable to obtain good quality GaInNAs QWs.
Improved performance in GaInNAs solar cells by hydrogen passivation
NASA Astrophysics Data System (ADS)
Fukuda, M.; Whiteside, V. R.; Keay, J. C.; Meleco, A.; Sellers, I. R.; Hossain, K.; Golding, T. D.; Leroux, M.; Al Khalfioui, M.
The effect of UV-activated hydrogenation on the performance of GaInNAs solar cells is presented. A proof-of-principle investigation was performed on non-optimum GaInNAs cells, which allowed a clearer investigation of the role of passivation on the intrinsic nitrogen-related defects in these materials. Upon optimized hydrogenation of GaInNAs, a significant reduction in the presence of defect and impurity based luminescence is observed as compared to that of unpassivated reference material. This improvement in the optical properties is directly transferred to an improved performance in solar cell operation, with a more than two-fold improvement in the external quantum efficiency and short circuit current density upon hydrogenation. Temperature dependent photovoltaic measurements indicate a strong contribution of carrier localization and detrapping processes, with non-radiative processes dominating in the reference materials, and evidence for additional strong radiative losses in the hydrogenated solar cells.
Laser operation of Ga(NAsP) lattice-matched to (001) silicon substrate
NASA Astrophysics Data System (ADS)
Liebich, S.; Zimprich, M.; Beyer, A.; Lange, C.; Franzbach, D. J.; Chatterjee, S.; Hossain, N.; Sweeney, S. J.; Volz, K.; Kunert, B.; Stolz, W.
The lattice-matched growth of the direct band gap material Ga(NAsP) is a seminal concept for the monolithic integration of III/V laser on a silicon substrate. Here, we report on the growth, characterization, and lasing properties of Ga(NAsP)/(BGa)(AsP) multi quantum well heterostructures embedded in (BGa)P cladding layers which were deposited on an exactly oriented (001) Si substrate. Structural investigations confirm a high crystal quality without any indication for misfit or threading dislocation formation. Laser operation between 800 nm and 900 nm of these broad area device structures was achieved under optical pumping as well as electrical injection for temperatures up to 150 K. This "proof of principle" points to the enormous potential of Ga(NAsP) as an optical complement to Si microelectronics.
Examination of Frameworks for Safe Integration of Intelligent Small UAS into the NAS
NASA Technical Reports Server (NTRS)
Logan, Michael J.
This paper discusses a proposed framework for the safe integration of small unmanned aerial systems (sUAS) into the National Airspace System (NAS). The paper briefly examines the potential uses of sUAS to build an understanding of the location and frequency of potential future flight operations based on the future applications of the sUAS systems. The paper then examines the types of systems that would be required to meet the application-level demand to determine "classes" of platforms and operations. A framework for categorization of the "intelligence" level of the UAS is postulated for purposes of NAS integration. Finally, constraints on the intelligent systems are postulated to ensure their ease of integration into the NAS.
High room-temperature optical gain in Ga(NAsP)/Si heterostructures
NASA Astrophysics Data System (ADS)
Koukourakis, N.; Bückers, C.; Funke, D. A.; Gerhardt, N. C.; Liebich, S.; Chatterjee, S.; Lange, C.; Zimprich, M.; Volz, K.; Stolz, W.; Kunert, B.; Koch, S. W.; Hofmann, M. R.
We analyze the modal gain of Ga(NAsP) multi quantum-well heterostructures pseudomorphically grown on (001) silicon substrate by metal-organic vapor-phase epitaxy. Using the variable stripe length method, we obtain high modal gain values up to 78 cm-1 at room temperature that are comparable to the values of common high quality III-V laser material. We find good agreement between experimental results and theoretically calculated gain spectra obtained using a microscopic model. The results underline the high potential of Ga(NAsP) as an active material for directly electrically pumped lasers on silicon substrate.
Photoluminescence and optical gain of Ga(NAsP) heterostructures pseudomorphically grown on silicon (001) substrate
NASA Astrophysics Data System (ADS)
Koukourakis, N.; Klimasch, M.; Funke, D. A.; Gerhardt, N. C.; Hofmann, M. R.; Liebich, S.; Zimprich, M.; Kunert, B.; Volz, K.; Stolz, W.
We present photoluminescence and modal gain measurements in a Ga(NAsP) single-quantum well sample pseudomorphically grown on silicon substrate. The temperature dependence indicates that disorder induced localization effects dominate the low temperature photoluminescence spectra. Nevertheless, using the variable stripe length method, we observe modal gain values up to 15 cm-1 at room temperature. These values are very promising, demonstrate the high optical quality of the new dilute nitride material Ga(NAsP) and underline its candidacy for electrically pumped lasers on silicon substrate.
GaNAs avalanche photodiode operating at 0.94 ?m
NASA Astrophysics Data System (ADS)
Kinsey, G. S.; Gotthold, D. W.; Holmes, A. L.; Streetman, B. G.; Campbell, J. C.
A p-i-n avalanche photodiode (APD) using GaNAs grown on GaAs has been demonstrated. Characterization of the excess noise in the material was used to determine that the ratio of ionization coefficients (k=?/?) is k=0.4. The quantum efficiency was above 25% at 0.94 ?m for 0.75% nitrogen incorporation. The APDs exhibited low dark currents (<60 nA/mm2 at 90% of breakdown) and a gain-bandwidth product of 42 GHz. GaNAs therefore shows promise for extending the operation of GaAs-based APDs to longer wavelengths.
Experimental evaluation of impact ionization in dilute nitride GaInNAs diodes
NASA Astrophysics Data System (ADS)
Tan, S. L.; Soong, W. M.; Green, J. E.; Steer, M. J.; Zhang, S.; Tan, L. J. J.; Ng, J. S.; Marko, I. P.; Sweeney, S. J.; Adams, A. R.; Allam, J.; David, J. P. R.
The anomalous behavior of impact ionization in dilute-nitride GaInNAs photodiodes with a range of nitrogen content below 4% is investigated. The ratio of hole- and electron-initiated ionization coefficients, k = ?/?, is enhanced by a factor up to ˜4 with increasing nitrogen content. The absolute ionization coefficients are suppressed by up to two orders of magnitude at low electric fields in samples with 3% N. The narrow band gap, suppressed impact ionization, and increased breakdown voltage characteristics of GaInNAs make it a suitable material for use as part of a composite collector in GaAs-based heterojunction bipolar transistors.
Unintentional Calcium Incorporation in Ga(Al, In, N)As
Hurst, J. B.; Lewis, S. D.; Oye, M. M.; Homes, A. L., Jr.; Ptak, A. J.; Reedy, R. C.
Unintentional calcium incorporation into GaInNAs causes an acceptor-type impurity, which limits the ability of {approx}1 eV GaInNAs-based solar cells to collect photogenerated current. Here, the authors focus on better understanding the conditions by which Ca is incorporated into GaInNAs. Various material combinations were grown including GaAs, InGaAs, GaInNAs, and Al(Ga)As. The materials were primarily grown by solid-source molecular-beam epitaxy (MBE) at {approx}400 and 580--620 C, with comparisons made to metal-organic chemical vapor deposition (MOCVD)-grown materials where appropriate. Calcium incorporation was measured through secondary ion mass spectrometry. There was no measurable Ca incorporation into MBE-grown GaAs at 580 C, but Ca incorporates into GaAs at low MBE growth temperatures ({approx}400 C) that are comparable to those typically used for GaInNAs. This suggests that the N species is not solely responsible for the observed Ca incorporation into MBE-grown GaInNAs; but rather, defects associated with the low temperature growth may also be a factor. The effects of defect-related Ca incorporation were further studied at interfaces between Al(Ga)As and GaAs, and substrates pretreated with an O2 plasma and NH4OH etch. Ca incorporation was observed at the interface between Al0.3Ga0.7As/GaAs, AlAs/GaAs, and at the epilayer/substrate interface for the pretreated samples. No Ca was observed in InGaAs samples grown by either MBE or MOCVD, suggesting the Ca incorporation into GaInNAs has something to do with the addition of nitrogen. Therefore, the authors propose that the likely causes of Ca incorporation into GaInNAs are a Ca--N affinity, defects generated by low temperature growth, defects generated by the incorporation of N into GaAs, or some combination thereof.
Comparison of Origin 2000 and Origin 3000 Using NAS Parallel Benchmarks
NASA Technical Reports Server (NTRS)
Turney, Raymond D.
This report describes results of benchmark tests on the Origin 3000 system currently being installed at the NASA Ames National Advanced Supercomputing facility. This machine will ultimately contain 1024 R14K processors. The first part of the system, installed in November, 2000 and named mendel, is an Origin 3000 with 128 R12K processors. For comparison purposes, the tests were also run on lomax, an Origin 2000 with R12K processors. The BT, LU, and SP application benchmarks in the NAS Parallel Benchmark Suite and the kernel benchmark FT were chosen to determine system performance and measure the impact of changes on the machine as it evolves. Having been written to measure performance on Computational Fluid Dynamics applications, these benchmarks are assumed appropriate to represent the NAS workload. Since the NAS runs both message passing (MPI) and shared-memory, compiler directive type codes, both MPI and OpenMP versions of the benchmarks were used. The MPI versions used were the latest official release of the NAS Parallel Benchmarks, version 2.3. The OpenMP versiqns used were PBN3b2, a beta version that is in the process of being released. NPB 2.3 and PBN 3b2 are technically different benchmarks, and NPB results are not directly comparable to PBN results.
D. Biondi; C. B. Reissmann
3 RESUMO: Este trabalho investigou a influência das condições ambientais das árvores nas relações dos teores foliares de N, P e K. As espécies utilizadas foram: acer ( Acer negundo L.) e ipê (Tabebuia chrysotricha ( Mart ex DC.) Standl). Foram selecionados locais com diferentes intensidades de tráfego de veículos (tráfego grande, médio, residenciais e parques), condições ambientais ( com
MPI versus MPI+OpenMP on IBM SP for the NAS benchmarks
Franck Cappello; Daniel Etiemble
The hybrid memory model of clusters of multiprocessors raises two issues: programming model and performance. Many parallel programs have been written by using the MPI standard. To evaluate the pertinence of hybrid models for existing MPI codes, we compare a unified model (MPI) and a hybrid one (OpenMP fine grain parallelization after profiling) for the NAS 2.3 benchmarks on two
Solution of linear systems of equations with a structural analysis code on the NAS CRAY2
E. L. Poole; A. L. Overman
Two methods for solving linear systems of equations on the NAS Cray-2 are described. One is a direct method; the other is an iterative method. Both methods exploit the architecture of the Cray-2, particularly the vectorization, and are aimed at structural analysis applications. To demonstrate and evaluate the methods, they were installed in a finite element structural analysis code denoted
78 FR 21084 - Proposed Amendment of Class D and E Airspace, and Establishment of Class E Airspace; Oceana NAS, VA
Federal Register 2010, 2011, 2012, 2013, 2014
...Tower at Oceana NAS (Apollo Soucek Field) operating...action would enhance the safety and airspace management...rules regarding aviation safety is found in Title 49...necessary to ensure the safety of aircraft and the efficient...airspace at Oceana NAS (Apollo Soucek Field),...
Proceedings of Institute of Mathematics of NAS of Ukraine 2002, Vol. 43, Part 1, 102110 Nonlinear Diffusion-Convection Systems
Popovych, Roman
Proceedings of Institute of Mathematics of NAS of Ukraine 2002, Vol. 43, Part 1, 102Â110 Nonlinear of Mathematics of NAS of Ukraine, 3 Tereshchenkivska Str., 01601 Kyiv-4, Ukraine E-mail: email@example.com Dept. of Math., Technical University, 24 Pershotravnevyi Prospekt, Poltava 1, Ukraine A class
Proceedings of Institute of Mathematics of NAS of Ukraine 2004, Vol. 50, Part 3, 11241127 Relation of Majorization for -Categories
Popovych, Roman
Proceedings of Institute of Mathematics of NAS of Ukraine 2004, Vol. 50, Part 3, 1124Â1127 Relation of Majorization for -Categories and -Wild Categories Stanislav A. KRUGLYAK Institute of Mathematics of NAS Ukraine, 3 Tereshchenkivs'ka Str., 01601 Kyiv-4, Ukraine In the present paper notions of majorization
Proceedings of Institute of Mathematics of NAS of Ukraine 2000, Vol. 30, Part 1, 146150. Towards a Classification of Realizations
Popovych, Roman
Proceedings of Institute of Mathematics of NAS of Ukraine 2000, Vol. 30, Part 1, 146Â150. Towards Ostrogradskogo Street, 314000 Poltava, Ukraine E-mail: firstname.lastname@example.com Institute of Mathematics of NAS of Ukraine, 3 Tereshchenkivska Street, 01004 Kyiv, Ukraine E-mail: firstname.lastname@example.com We classify
Proceedings of Institute of Mathematics of NAS of Ukraine 2004, Vol. 50, Part 1, 266270 Symmetry Reduction
Popovych, Roman
Proceedings of Institute of Mathematics of NAS of Ukraine 2004, Vol. 50, Part 1, 266Â270 Symmetry, 2 Akademicka Str., Bialystok, Poland; Institute of Geophysics of NAS of Ukraine, 32 Palladin Ave., Kyiv, Ukraine E-mail: email@example.com We propose the symmetry reduction method of partial
Proceedings of Institute of Mathematics of NAS of Ukraine 2004, Vol. 50, Part 3, 12281235 Nonlinear Symmetries of Variational Calculus
Popovych, Roman
Proceedings of Institute of Mathematics of NAS of Ukraine 2004, Vol. 50, Part 3, 1228-Compact Manifolds Alexander Val. ANTONIOUK Institute of Mathematics of NAS Ukraine, 3 Tereshchenkivs'ka Str., 01601 Kyiv-4, Ukraine E-mail: firstname.lastname@example.com This talk is devoted to the discussion of symmetries
Proceedings of Institute of Mathematics of NAS of Ukraine 2004, Vol. 50, Part 1, 290297 Group Classification with Respect
Popovych, Roman
Proceedings of Institute of Mathematics of NAS of Ukraine 2004, Vol. 50, Part 1, 290Â297 Group Classification with Respect to Hidden Symmetry Irina YEHORCHENKO Institute of Mathematics of NAS Ukraine, 3 Tereshchenkivs'ka Str., 01601 Kyiv-4, Ukraine E-mail: firstname.lastname@example.com We present approaches to systematic
Proceedings of Institute of Mathematics of NAS of Ukraine 2004, Vol. 50, Part 3, 12021206 Spinor Representation of Lie Algebra
Popovych, Roman
Proceedings of Institute of Mathematics of NAS of Ukraine 2004, Vol. 50, Part 3, 1202Â1206 Spinor Department, Taras Shevchenko Kyiv University, 6 Academician Glushkov Ave., 03127 Kyiv, Ukraine E-mail: firstname.lastname@example.com Institute of Physics of NAS of Ukraine, 46 Nauky Ave., 03028 Kyiv, Ukraine E-mail: firstname.lastname@example.com Spinor
Proceedings of Institute of Mathematics of NAS of Ukraine 2000, Vol. 30, Part 1, 231238. Modelling System for Relaxing Media.
Popovych, Roman
Proceedings of Institute of Mathematics of NAS of Ukraine 2000, Vol. 30, Part 1, 231Â238. Modelling.A. VLADIMIROV Division of Geodynamics of Explosion, Subbotin Institute of Geophysics, NAS of Ukraine, Khmelnicki Str. 63-B, Kyiv 54, Ukraine E-mail: email@example.com A model describing non-equilibrium processes
Defect study of molecular beam epitaxy grown undoped GaInNAsSb thin film using junction-capacitance spectroscopy
Monirul Islam, Muhammad; Miyashita, Naoya; Ahsan, Nazmul; Okada, Yoshitaka [Research Center for Advanced Science and Technology (RCAST), The University of Tokyo, 4-6-1 Komaba, Meguro-Ku, Tokyo 153-8904 (Japan)] [Research Center for Advanced Science and Technology (RCAST), The University of Tokyo, 4-6-1 Komaba, Meguro-Ku, Tokyo 153-8904 (Japan)
Defects in undoped GaInNAsSb thin film (i-GaInNAsSb) were investigated by junction-capacitance technique using admittance and transient photocapacitance (TPC) spectroscopy. An electron trap D2 was identified at 0.34 eV below the conduction band (E{sub C}) of i-GaInNAsSb using admittance spectroscopy. Optical transition of valance band (E{sub V}) electrons to a localized state OH1 (E{sub V} + 0.75 eV) was manifested in negative TPC signal. Combined activation energy of OH1 and D2 defect corresponds to the band-gap of i-GaInNAsSb, suggesting that OH1/D2 acts as an efficient recombination center. TPC signal at {approx}1.59 eV above E{sub V} was attributed to the nitrogen-induced localized state in GaInNAsSb.
Enhanced-Depletion-Width GaInNAs Solar Cells Grown by Molecular-Beam Epitaxy
Ptak, A. J.; Friedman, D. J.
The 3-junction, GaInP2/GaAs/Ge solar cell is a non-optimized structure due to excess light falling on the Ge junction. Because of this, a fourth junction inserted between the GaAs and Ge subcells could use the excess light and provide an increase in device efficiency. Unfortunately, the leading candidate material, GaInNAs, suffers from very low minority-carrier diffusion lengths compared to its parent compound, GaAs. These low diffusion lengths do not allow for the collection of adequate current to keep the overall 4-junction structure current matched. If the currents generated from the GaInNAs subcell are increased, the possibility exists for practical efficiencies of greater than 40% from this structure.
Photoluminescence study of Be-acceptors in GaInNAs epilayers
NASA Astrophysics Data System (ADS)
Tsai, Y.; Barman, B.; Scrace, T.; Fukuda, M.; Whiteside, V. R.; Sellers, I. R.; Leroux, M.; Khalfioui, M. Al; Petrou, A.
We have studied Be-acceptors in a p-type GaInNAs epilayer using magneto-luminescence spectroscopy. The band edge photoluminescence (PL) spectra at T = 7 K contain two features: the first is associated with the free exciton while the second with the conduction band to acceptor (CB ? A) transition. The intensity of the latter decreases with increasing temperature while the excitonic feature survives up to T = 250 K. From the energies of the two PL features, as well as the exciton binding energy in GaInNAs, we determined the Be-acceptor binding energy to be equal to 42 meV. The energy of the CB ? A feature varies linearly with magnetic field B and has a slope of 5.5 ×10-4 eV/T.
Nonexponential photoluminescence transients in a Ga(NAsP) lattice matched to a (001) silicon substrate
NASA Astrophysics Data System (ADS)
Jandieri, K.; Kunert, B.; Liebich, S.; Zimprich, M.; Volz, K.; Stolz, W.; Gebhard, F.; Baranovskii, S. D.; Koukourakis, N.; Gerhardt, N. C.; Hofmann, M. R.
Ga(NAsP) grown lattice-matched on (001) silicon substrate is a very promising material for future integrated, electrically pumped lasers on silicon. Here, we present experimental and theoretical studies of the time-resolved photoluminescence in Ga(NAsP)/Si quantum well structures. The experimental results obtained at 10 K show a strong nonexponential transient behavior for the photoluminescence signal. A detailed comparison with theoretical calculations based on rate equations and on straightforward Monte Carlo simulations reveals that this effect is controlled by an interplay between the fast capture of carriers on nonradiative centers and the slow radiative recombination via localized states. We demonstrate that the measurement of the time-resolved photoluminescence can serve as a convenient tool for estimating the relative concentrations of nonradiative and radiative centers in compound materials.
NAS technical summaries. Numerical aerodynamic simulation program, March 1992 - February 1993
NASA Technical Reports Server (NTRS)
NASA created the Numerical Aerodynamic Simulation (NAS) Program in 1987 to focus resources on solving critical problems in aeroscience and related disciplines by utilizing the power of the most advanced supercomputers available. The NAS Program provides scientists with the necessary computing power to solve today's most demanding computational fluid dynamics problems and serves as a pathfinder in integrating leading-edge supercomputing technologies, thus benefitting other supercomputer centers in government and industry. The 1992-93 operational year concluded with 399 high-speed processor projects and 91 parallel projects representing NASA, the Department of Defense, other government agencies, private industry, and universities. This document provides a glimpse at some of the significant scientific results for the year.
MBE grown GaInNAs solar cells for multijunction applications
David Jackrel; Homan Yuen; Junxian Fu; Seth Bank; Xiaojun Yu; Zhilong Rao; James S. Harris
Triple-junction cells composed of III-V materials currently hold the world record for photovoltaic efficiency. In order to further increase cell efficiency in the future 4- and 5-junction cells incorporating a sub-cell with a bandgap of roughly 1.0 eV will be required. In this study 1.0 eV bandgap GaInNAs devices grown by solid source molecular beam epitaxy are investigated in terms
Effects of Bismuth on Wide-Depletion-Width GaInNAs Solar Cells
A. J. Ptak; C.-S. Jiang; R. C. Reedy
GaInNAs solar cells could be useful in next-generation multijunction solar cells if issues surrounding low photocurrents and photovoltages are surmounted. Wide-depletion-width devices generate significant photocurrent using a p-i-n structure grown by molecular beam epitaxy, but these depletion widths are only realized in a region of parameter space that leads to rough surface morphologies. Here, bismuth is explored as a surfactant
Enabling a modernized NAS ATM infrastructure in support of trajectory based operations
Andrew A. Aslinger; William S. Leber; Mark A. Hopkins
The concept of Trajectory-Based Operations (TBO) is a cornerstone of the FAA NextGen CONOPS and the mid-term concepts of Trajectory Operations (TOps) will provide the path to TBO's far-term capabilities. These concepts of operation and use require a unified approach to bring both CNS and ATM capabilities together into effective methods and approaches for managing National Airspace System (NAS) throughput
The NAS EarlyBird ProgrammePartnership with Parents in Early Intervention
Jane Shields
Early intervention bridges the gap between early diagnosis and appropriate educational placement. The National Autistic Society has developed an autism-specific three-month parent package, the NAS EarlyBird Programme, that emphasizes partnership with parents. Six families participate in each three-month programme, which combines weekly group training sessions for parents with individualized home visits. During the programme parents learn to understand autism, to
Unmanned Aircraft Systems (UAS) Integration in the National Airspace System (NAS) Project
NASA Technical Reports Server (NTRS)
Griner, James H.
NASA's UAS Integration in the NAS project, has partnered with Rockwell Collins to develop a concept Control and Non-Payload Communication system prototype radio, operating on recently allocated UAS frequency spectrum bands. The prototype radio will be used to validate initial proposed performance requirements for UAS control communications. This presentation will give an overview of the current status of the design, development, and flight test planning for this prototype radio.
GaNAs avalanche photodiode operating at 0.94 mum
G. S. Kinsey; D. W. Gotthold; A. L. Holmes; B. G. Streetman; J. C. Campbell
A p-i-n avalanche photodiode (APD) using GaNAs grown on GaAs has been demonstrated. Characterization of the excess noise in the material was used to determine that the ratio of ionization coefficients (k=beta\\/alpha) is k=0.4. The quantum efficiency was above 25% at 0.94 mum for 0.75% nitrogen incorporation. The APDs exhibited low dark currents (<60 nA\\/mm2 at 90% of breakdown) and
Selective Defects Passivation of GaInNAs Solar Cells by Hydrogenation
NASA Astrophysics Data System (ADS)
Fukuda, Miwa; Whiteside, Vincent R.; Sellers, Ian R.; Al Khalfioui, Mohamed; Leroux, Mathieu; Phinney, Lucas; Hossain, Khalid
While GaInNAs has the potential to be a fourth-junction in multi-junction solar cells it has proved difficult to achieve the optimal alloy composition due to the low solubility of nitrogen in these materials. At this point we investigate the possibility of improving the performance of GaInNAs using hydrogenation to selectively passivate mid-gap defects, while preserving the functionality of substitutional nitrogen. Temperature dependent photoluminescence measurements of the intrinsic region of a GaInNAs p-i-n solar cell show a classic ``s-shape'' associated with localization prior to hydrogenation, while after hydrogenation no sign of the ``s-shape'' is evident. The preliminary investigations of the effect of hydrogenation on the efficiency of carrier transport in the solar cells will also be presented. Amethyst Research Inc.'s photon-assisted defect mitigation-hydrogenation technique is usually a low temperature process; however, the annealing effects will be de-convoluted from that of hydrogenation. Research supported by Amethyst Research Inc. through the state of Oklahoma, OARS 12.2-040 program.
Effects of Bismuth on Wide-Depletion-Width GaInNAs Solar Cells
Ptak, A. J.; France, R.; Jiang, C.-S.; Reedy, R. C.
GaInNAs solar cells could be useful in next-generation multijunction solar cells if issues surrounding low photocurrents and photovoltages are surmounted. Wide-depletion-width devices generate significant photocurrent using a p-i-n structure grown by molecular beam epitaxy, but these depletion widths are only realized in a region of parameter space that leads to rough surface morphologies. Here, bismuth is explored as a surfactant for the growth of GaInNAs solar cells. Very low fluxes of Bi are effective at maintaining smooth surfaces, even at high growth temperatures and In contents. However, Bi also increases the net donor concentration in these materials, manifested in our n-on-p device structures as a pn-junction that moves deeper into the base layer with increasing Bi fluxes. Quantum efficiency modeling and scanning kelvin probe microscopy measurements confirm the type conversion of the base layer from p type to n type. Bi incorporation in GaAsBi samples shows signs of surface segregation, leading to a finite buildup time, and this effect may lead to slow changes in the electrical properties of the GaInNAs(Bi) devices. Bi also appears to create a defect level, although this defect level is not deleterious enough to increase the dark current in the devices.
NAS technical summaries: Numerical aerodynamic simulation program, March 1991 - February 1992
NASA Technical Reports Server (NTRS)
NASA created the Numerical Aerodynamic Simulation (NAS) Program in 1987 to focus resources on solving critical problems in aeroscience and related disciplines by utilizing the power of the most advanced supercomputers available. The NAS Program provides scientists with the necessary computing power to solve today's most demanding computational fluid dynamics problems and serves as a pathfinder in integrating leading-edge supercomputing technologies, thus benefiting other supercomputer centers in Government and industry. This report contains selected scientific results from the 1991-92 NAS Operational Year, March 4, 1991 to March 3, 1992, which is the fifth year of operation. During this year, the scientific community was given access to a Cray-2 and a Cray Y-MP. The Cray-2, the first generation supercomputer, has four processors, 256 megawords of central memory, and a total sustained speed of 250 million floating point operations per second. The Cray Y-MP, the second generation supercomputer, has eight processors and a total sustained speed of one billion floating point operations per second. Additional memory was installed this year, doubling capacity from 128 to 256 megawords of solid-state storage-device memory. Because of its higher performance, the Cray Y-MP delivered approximately 77 percent of the total number of supercomputer hours used during this year.
Proceedings of Institute of Mathematics of NAS of Ukraine 2004, Vol. 50, Part 3, 10711078 Permutations in Tensor Products of Factors,
Popovych, Roman
Proceedings of Institute of Mathematics of NAS of Ukraine 2004, Vol. 50, Part 3, firstname.lastname@example.com Institute of Mathematics of NAS Ukraine, 3 Tereshchenkivs'ka Str., 01601 Kyiv-4, Ukraine E-mail: kalyuz
Proceedings of Institute of Mathematics of NAS of Ukraine 2004, Vol. 50, Part 3, 11841191 On the LiouvilleArnold Integrable Flows Related
Popovych, Roman
Proceedings of Institute of Mathematics of NAS of Ukraine 2004, Vol. 50, Part 3, 1184 of Mathematics of NAS Ukraine, 3 Tereshchenkivs'ka Str., 01601 Kyiv-4, Ukraine E-mail: firstname.lastname@example.com 2 Dept´ow, Poland; Dept. of Nonlinear Math. Analysis at the Institute of APMM of NAS of Ukraine, 3b Naukova Str
Unmanned Aircraft Systems (UAS) Integration in the National Airspace System (NAS) Project. NASA Contributions to the SARP WC Definition
NASA Technical Reports Server (NTRS)
Randall, Debra K.; Consiglio, Maria Cristina; Santiago, Confesor
To better inform sense and avoid research needs and to understand ongoing investigation of potential solutions that ultimately lead to the assisting the FAA with their Congressional mandate to fly UAS in the NAS.
THE NAS PARALLEL BENCHMARKS D. Bailey, E. Barszcz, J. Barton, D. Browning, R. Carter, L. Dagum, R.
Bailey, David H.
THE NAS PARALLEL BENCHMARKS D. Bailey, E. Barszcz, J. Barton, D. Browning, R. Carter, L. Dagum, R 1991. Bailey, Barszcz, Barton, Carter, and Lasinski are with NASA Ames Research Center. Dagum, Fatoohi
Proceedings of Institute of Mathematics of NAS of Ukraine 2000, Vol. 30, Part 1, 249254. On Some New Classes
Popovych, Roman
Proceedings of Institute of Mathematics of NAS of Ukraine 2000, Vol. 30, Part 1, 249Â254. On Some of Ukraine, 3 Tereshchenkivska Str., Kyiv, Ukraine E-mail: firstname.lastname@example.com We communicate some recent
Board on Physics and Astronomy Tel. (202) 334 3520 Fax. (202) 334 3575 Email: email@example.com
Board on Physics and Astronomy Tel. (202) 334 3520 Fax. (202) 334 3575 Email: email@example.com BURNING PLASMA ASSESSMENT COMMITTEE Agenda - January 17-19, 2003 Scripps Institution of Oceanography : 8602 La
Board on Physics and Astronomy Tel. (202) 334 3520 Fax. (202) 334 3575 Email: email@example.com
Board on Physics and Astronomy Tel. (202) 334 3520 Fax. (202) 334 3575 Email: firstname.lastname@example.com BURNING PLASMA ASSESSMENT COMMITTEE Agenda September 17-18, 2002 Room 201, The National Academies. 500 5th
Effect of antimony on the deep-level traps in GaInNAsSb thin films
Islam, Muhammad Monirul, E-mail: firstname.lastname@example.com; Miyashita, Naoya; Ahsan, Nazmul; Okada, Yoshitaka [Research Center for Advanced Science and Technology (RCAST), The University of Tokyo, 4-6-1 Komaba, Meguro ku, Tokyo 153-8904 (Japan); Sakurai, Takeaki; Akimoto, Katsuhiro [Institute of Applied Physics, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8573 (Japan)
Admittance spectroscopy has been performed to investigate the effect of antimony (Sb) on GaInNAs material in relation to the deep-level defects in this material. Two electron traps, E1 and E2 at an energy level 0.12 and 0.41?eV below the conduction band (E{sub C}), respectively, were found in undoped GaInNAs. Bias-voltage dependent admittance confirmed that E1 is an interface-type defect being spatially localized at the GaInNAs/GaAs interface, while E2 is a bulk-type defect located around mid-gap of GaInNAs layer. Introduction of Sb improved the material quality which was evident from the reduction of both the interface and bulk-type defects.
Photocurrent of 1 eV GaInNAs lattice-matched to GaAs
J. F. Geisz; D. J. Friedman; J. M. Olson; S. R. Kurtz; B. M. Keyes
The spectral photocurrent response, or quantum efficiency, of GaInNAs lattice-matched to GaAs with a bandgap of 1eV has been measured in an electrochemical cell in order to optimize material quality for use in a multijunction solar cell lattice-matched to GaAs or Ge. GaInNAs with about 3% nitrogen grown by MOVPE using dimethylhydrazine as a nitrogen source was found to be
Anisotropic lattice deformation of InAs self-assembled quantum dots embedded in GaNAs strain compensating layers
Naoki Matsumura; Shunichi Muto; Sasilaka Ganapathy; Ikuo Suemune; Ken Numata; Konami Yabuta
Lattice deformations of InAs self-assembled quantum dots, which were grown on (001) GaAs substrates and embedded in GaNAs strain compensating layers (SCLs), were examined with an ion-channeling method in Rutherford backscattering spectrometry. The channeling experiments demonstrated that the increase of the nitrogen concentrations in the GaNAs SCLs caused the indium lattice displacements along the [001] growth direction while those parallel
Anisotropic Lattice Deformation of InAs Self-Assembled Quantum Dots Embedded in GaNAs Strain Compensating Layers
Naoki Matsumura; S. Muto; S. Ganapathy; Ikuo Suemune; Ken Numata; Konami Yabuta
Lattice deformations of InAs self-assembled quantum dots, which were grown on (001)GaAs substrates and embedded in GaNAs strain compensating layers (SCLs), were examined with an ion-channeling method in Rutherford backscattering spectrometry. The channeling experiments demonstrated that the increase of the nitrogen concentrations in the GaNAs SCLs caused the indium lattice displacements along the [001] growth direction while those parallel to
Long wavelength InAs self-assembled quantum dots embedded in GaNAs strain-compensating layers
Ryuji Oshima; Takayuki Hashimoto; Hidemi Shigekawa; Yoshitaka Okada
We investigated the effect of GaNAs strain-compensating layers (SCLs) on the properties of InAs self-assembled quantum dots (QDs) grown on GaAs (001) substrates. The GaNAs material can be used as SCL thereby minimizing the net strain, and thus is advantageous for multi-stacking of InAs QDs structures and achieving long wavelength emission. The emission wavelength of InAs QDs can be tuned
R&D on small solar Stirling engines TNT-2 and 3, NAS-1
NASA Astrophysics Data System (ADS)
Isshiki, Naotsugu; Watanabe, Hiroichi; Shishido, Koro; Watanabe, Kuniya
A unique 1-kW solar Stirling engine, the TNT-1, 2, and 3, is tested utilizing the internal solar heating method. Two solar concentrator dishes are tested for a prototype for future large solar Stirling power plant systems. These Stirling engines have transparent cylinder heads at their top made of quartz glass, and the solar beam concentrated by the solar dishes heats up directly the inside meshes installed upon the displacer piston, penetrating through the quartz glass. An atmosphere hot air Stirling engine NAS-1 is under test, which has rubber diaphram power piston and quite simple construction.
Monolithic GaInNAsSb/GaAs VECSEL emitting at 1550 nm
NASA Astrophysics Data System (ADS)
Korpijärvi, Ville-Markus; Kantola, Emmi L.; Leinonen, Tomi; Guina, Mircea
We report the first monolithic GaAs-based vertical external-cavity surface-emitting laser (VECSEL) operating at 1550 nm. The VECSEL is based on a gain mirror which was grown by plasma-assisted molecular beam epitaxy and comprises 8 GaInNAsSb/GaAs quantum wells and an AlAs/GaAs distributed Bragg reflector. When pumped by an 808 nm diode laser, the laser exhibited an output power of 80 mW for a mount temperature of 16 °C.
1eV solar cells with GaInNAs active layer
D. J. Friedman; J. F. Geisz; S. R. Kurtz; J. M. Olson
We demonstrate working prototypes of a GaInNAs-based solar cell lattice-matched to GaAs with photoresponse down to 1eV. This device is intended for use as the third junction of future-generation ultrahigh-efficiency three- and four-junction devices. Under the AM1.5 direct spectrum with all the light higher in energy than the GaAs band gap filtered out, the prototypes have open-circuit voltages ranging from
A Framework for Safe Integration of Small UAS Into the NAS
NASA Technical Reports Server (NTRS)
Logan, Michael J.; Bland, Geoffrey; Murray, Jennifer
This paper discusses a proposed framework for the safe integration of small unmanned aerial systems (sUAS) into the National Airspace System (NAS). The paper examines the potential uses of sUAS to build an understanding of the location and frequency of potential future flight operations based on the future applications of the sUAS systems. The paper then examines the types of systems that would be required to meet the application-level demand to determine classes of platforms and operations. Finally, a framework is proposed for both airworthiness and operations that attempts to balance safety with utility for these important systems.
The NAS EarlyBird Programme: partnership with parents in early intervention. The National Autistic Society.
Shields, J
Early intervention bridges the gap between early diagnosis and appropriate educational placement. The National Autistic Society has developed an autism-specific three-month parent package, the NAS EarlyBird Programme, that emphasizes partnership with parents. Six families participate in each three-month programme, which combines weekly group training sessions for parents with individualized home visits. During the programme parents learn to understand autism, to build social communication, and to analyse and use structure, so as to prevent inappropriate behaviours. The use of video and the group dynamic amongst families are important components of the programme. An efficacy study evaluated the pilot programme and further monitoring is in progress. Training courses in the licensed use of the NAS EarlyBird Programme are now available for teams of professionals with prior experience of autism. Strengths and weaknesses of the programme are discussed. This short-term, affordable package, with supporting evidence of efficacy, offers a model of early intervention that is very popular with parents. PMID:11708389
Devgun, Jas S., Ph.D.
Lack of consistent free release standards for solid materials has been an issue that has been around for several decades. The Nuclear Regulatory Commission (NRC) has had specific and dose-based standards for the release of liquids and gases for several decades, but no regulatory mechanisms for the release of solid materials from a nuclear power plant. Even though free releases of small quantities of solid materials continue under existing guidelines from operating plants, the regulatory void creates major difficulties for the bulk materials that result from decommissioning projects. For the nation's fleet of nuclear reactors the cost of this regulatory void could be as high as $10 billion. The NRC has recently resumed the enhanced rulemaking process that was originally initiated in 1999 but was deferred pending a study by the National Academy of Sciences (NAS)/National Research Council. The NAS report and recommendations were issued in March 2002 and the NRC decided in October 2002 to resume the rulemaking process. This paper provides an overview of the developments in this area. It specifically discusses the applicability of ANSI N13.12 as a consensus standard that should be seriously considered for adoption as a regulatory standard.
Web Prep: How to Prepare NAS Reports For Publication on the Web
NASA Technical Reports Server (NTRS)
Walatka, Pamela; Balakrishnan, Prithika; Clucas, Jean; McCabe, R. Kevin; Felchle, Gail; Brickell, Cristy
This document contains specific advice and requirements for NASA Ames Code IN authors of NAS reports. Much of the information may be of interest to other authors writing for the Web. WebPrep has a graphic Table of Contents in the form of a WebToon, which simulates a discussion between a scientist and a Web publishing consultant. In the WebToon, Frequently Asked Questions about preparing reports for the Web are linked to relevant text in the body of this document. We also provide a text-only Table of Contents. The text for this document is divided into chapters: each chapter corresponds to one frame of the WebToons. The chapter topics are: converting text to HTML, converting 2D graphic images to gif, creating imagemaps and tables, converting movie and audio files to Web formats, supplying 3D interactive data, and (briefly) JAVA capabilities. The last chapter is specifically for NAS staff authors. The Glossary-Index lists web related words and links to topics covered in the main text.
Growth optimization and optical properties of AlGaNAs alloys
Kolhatkar, Gitanjali; Boucherif, Abderraouf; Aimez, Vincent; Arès, Richard, E-mail: email@example.com [Institut interdisciplinaire d'innovation technologique (3IT), Université de Sherbrooke, 3000, boul. Université, J1K 0A5 Sherbrooke, Québec (Canada); Laboratoire Nanotechnologies Nanosystèmes (LN2)- CNRS UMI-3463, Université de Sherbrooke, 3000 Boulevard Université, Sherbrooke J1K OA5, Québec (Canada); Valdivia, Christopher E.; Wallace, Steven G.; Fafard, Simon [Cyrium Technologies Inc., 50 Hines Road, K2K 2M5 Ottawa, Ontario (Canada)
The effect of Al on the surface morphology of chemical beam epitaxy grown AlGaNAs alloys is studied. Pits attributed to N clustering appearing on the dilute nitride surface become smaller, denser, and more uniformly distributed in the presence of Al. This reveals that the introduction of Al results in more homogenous N atoms spatial distribution. A growth temperature study reveals the formation of 3D structures at high temperature due to phase separation. The density of these structures decreases, while their diameter and height increase when the temperature is raised from 380?°C to 565?°C. At growth temperatures in the 380–420?°C range, the phase separation is suppressed and the growth mode is 2D. At 420?°C, the N incorporation is also maximized, making it the optimum temperature. The absorption coefficient and the bandgap of AlGaNAs alloys are extracted from transmittance measurement. A good agreement is obtained between the experimentally measured bandgap and the theoretical values calculated using the band anticrossing model. A bandgap as low as 1.22?eV was reached using Al and N concentrations of ?15% and ?3.4%, respectively.
The Performance of the NAS HSPs in 1st Half of 1994
NASA Technical Reports Server (NTRS)
Bergeron, Robert J.; Walter, Howard (Technical Monitor)
During the first six months of 1994, the NAS (National Airspace System) 16-CPU Y-MP C90 Von Neumann (VN) delivered an average throughput of 4.045 GFLOPS while the ACSF (Aeronautics Consolidated Supercomputer Facility) 8-CPU Y-MP C90 Eagle averaged 1.658 GFLOPS. The VN rate represents a machine efficiency of 26.3% whereas the Eagle rate corresponds to a machine efficiency of 21.6%. VN displayed a greater efficiency than Eagle primarily because the stronger workload demand for its CPU cycles allowed it to devote more time to user programs and less time to idle. An additional factor increasing VN efficiency was the ability of the UNICOS 8.0 Operating System to deliver a larger fraction of CPU time to user programs. Although measurements indicate increasing vector length for both workloads, insufficient vector lengths continue to hinder HSP (High Speed Processor) performance. To improve HSP performance, NAS should continue to encourage the HSP users to modify their codes to increase program vector length.
Growth and characterisation of Ga(NAsBi) alloy by metal-organic vapour phase epitaxy
NASA Astrophysics Data System (ADS)
Bushell, Z. L.; Ludewig, P.; Knaub, N.; Batool, Z.; Hild, K.; Stolz, W.; Sweeney, S. J.; Volz, K.
This paper summarises results of the epitaxial growth of Ga(NAsBi) by metal-organic vapour phase epitaxy (MOVPE) and the subsequent optical and structural characterisations of the samples. Ga(NAsBi)/GaAs multi-quantum well (MQW) samples are grown at 400 °C and single layers at 450 °C on GaAs (001) substrates. Triethylgallium (TEGa), tertiarybutylarsine (TBAs), trimethylbismuth (TMBi) and unsymmetrical dimethylhydrazine (UDMHy) are used as precursors. Secondary ion mass spectrometry (SIMS) shows that the Bi content is independent of the N content in the alloy. It is found that the N content depends on both UDMHy and TMBi supply during growth. High resolution X-ray diffraction (HR-XRD), scanning transmission electron microscopy (STEM) and atomic force microscopy (AFM) measurements show that samples with good crystalline quality can be realised. For samples containing 1.8% Bi and up to 1.8% N grown at 450 °C, photoreflectance spectroscopy (PR) shows a decrease in the band gap with increasing N content of 141±22 meV/% N.
NAS Demand Predictions, Transportation Systems Analysis Model (TSAM) Compared with Other Forecasts
NASA Technical Reports Server (NTRS)
Viken, Jeff; Dollyhigh, Samuel; Smith, Jeremy; Trani, Antonio; Baik, Hojong; Hinze, Nicholas; Ashiabor, Senanu
The current work incorporates the Transportation Systems Analysis Model (TSAM) to predict the future demand for airline travel. TSAM is a multi-mode, national model that predicts the demand for all long distance travel at a county level based upon population and demographics. The model conducts a mode choice analysis to compute the demand for commercial airline travel based upon the traveler s purpose of the trip, value of time, cost and time of the trip,. The county demand for airline travel is then aggregated (or distributed) to the airport level, and the enplanement demand at commercial airports is modeled. With the growth in flight demand, and utilizing current airline flight schedules, the Fratar algorithm is used to develop future flight schedules in the NAS. The projected flights can then be flown through air transportation simulators to quantify the ability of the NAS to meet future demand. A major strength of the TSAM analysis is that scenario planning can be conducted to quantify capacity requirements at individual airports, based upon different future scenarios. Different demographic scenarios can be analyzed to model the demand sensitivity to them. Also, it is fairly well know, but not well modeled at the airport level, that the demand for travel is highly dependent on the cost of travel, or the fare yield of the airline industry. The FAA projects the fare yield (in constant year dollars) to keep decreasing into the future. The magnitude and/or direction of these projections can be suspect in light of the general lack of airline profits and the large rises in airline fuel cost. Also, changes in travel time and convenience have an influence on the demand for air travel, especially for business travel. Future planners cannot easily conduct sensitivity studies of future demand with the FAA TAF data, nor with the Boeing or Airbus projections. In TSAM many factors can be parameterized and various demand sensitivities can be predicted for future travel. These resulting demand scenarios can be incorporated into future flight schedules, therefore providing a quantifiable demand for flights in the NAS for a range of futures. In addition, new future airline business scenarios are investigated that illustrate when direct flights can replace connecting flights and larger aircraft can be substituted, only when justified by demand.
Comparison of 250 MHz R10K Origin 2000 and 400 MHz Origin 2000 Using NAS Parallel Benchmarks
NASA Technical Reports Server (NTRS)
Turney, Raymond D.; Thigpen, William W. (Technical Monitor)
This report describes results of benchmark tests on Steger, a 250 MHz Origin 2000 system with R10K processors, currently installed at the NASA Ames National Advanced Supercomputing (NAS) facility. For comparison purposes, the tests were also run on Lomax, a 400 MHz Origin 2000 with R12K processors. The BT, LU, and SP application benchmarks in the NAS Parallel Benchmark Suite and the kernel benchmark FT were chosen to measure system performance. Having been written to measure performance on Computational Fluid Dynamics applications, these benchmarks are assumed appropriate to represent the NAS workload. Since the NAS runs both message passing (MPI) and shared-memory, compiler directive type codes, both MPI and OpenMP versions of the benchmarks were used. The MPI versions used were the latest official release of the NAS Parallel Benchmarks, version 2.3. The OpenMP versions used were PBN3b2, a beta version that is in the process of being released. NPB 2.3 and PBN3b2 are technically different benchmarks, and NPB results are not directly comparable to PBN results.
Probing the nature of carrier localization in GaInNAs epilayers by optical methods
NASA Astrophysics Data System (ADS)
Tsai, Y.; Barman, B.; Scrace, T.; Lindberg, G.; Fukuda, M.; Whiteside, V. R.; Keay, J. C.; Johnson, M. B.; Sellers, I. R.; Al Khalfioui, M.; Leroux, M.; Weinstein, B. A.; Petrou, A.
Photoluminescence (PL), optical pumping, and reflectance studies of nominally undoped and p-type GaInNAs epilayers are presented. The PL peak energy of the nominally undoped sample exhibits an S-shaped dependence on temperature for T < 50 K. This is attributed to recombination of bound excitons localized on traps. The energy of the PL circular-polarization maximum coincides with the energy of the free-exciton related reflectance feature at all temperatures. In heavily p-type samples the S-shaped temperature-dependence of the PL energy disappears, and the PL peak and circular polarization maximum coincide with the reflectance feature at all temperatures, indicating that the PL is free-exciton-like.
>8W GaInNAs VECSEL emitting at 615 nm
NASA Astrophysics Data System (ADS)
Leinonen, Tomi; Penttinen, Jussi-Pekka; Korpijärvi, Ville-Markus; Kantola, Emmi; Guina, Mircea
We report a high-power VECSEL emitting <8W around 615 nm. The gain chip of the laser was grown by plasmaassisted molecular beam epitaxy and it comprised 10 GaInNAs quantum wells. The VECSEL cavity had a V-shaped geometry and a 10-mm-long non-critically phase-matched LBO crystal for second harmonic generation. The cavity incorporated also an etalon and a birefringent filter for controlling the output wavelength. With the aid of the secondharmonic output and the infrared light leaking out from the laser cavity, the single-pass conversion efficiency of the crystal was estimated to have a value of 0.75%.
Temperature dependence and physical properties of Ga(NAsP)/GaP semiconductor lasers
NASA Astrophysics Data System (ADS)
Chamings, J.; Adams, A. R.; Sweeney, S. J.; Kunert, B.; Volz, K.; Stolz, W.
We report on the properties of GaNAsP/GaP lasers which offer a potential route to producing lasers monolithically on silicon. Lasing has been observed over a wide temperature range with pulsed threshold current density of 2.5 kA/cm2 at 80 K (? =890 nm). Temperature dependence measurements show that the radiative component of the threshold is relatively temperature stable while the overall threshold current is temperature sensitive. A sublinear variation of spontaneous emission versus current coupled with a decrease in external quantum efficiency with increasing temperature and an increase in threshold current with hydrostatic pressure implies that a carrier leakage path is the dominant carrier recombination mechanism.
Efficiency-limiting processes in Ga(NAsP)/GaP quantum well lasers
NASA Astrophysics Data System (ADS)
Hossain, N.; Jin, S. R.; Liebich, S.; Zimprich, M.; Volz, K.; Kunert, B.; Stolz, W.; Sweeney, S. J.
We report on the carrier recombination mechanisms in dilute nitride Ga(NAsP)/GaP quantum well lasers. Spontaneous emission measurements show that defect-related recombination in the devices is less significant compared with other GaAs-based dilute nitride lasers. From temperature dependent measurements, we find that the threshold current density, Jth is dominated by non-radiative recombination process(es), which account for at least 91% of Jth at room temperature. The characteristic temperature, T0 (T1) is measured to be ˜104 K (˜99 K) around 200 K, which drops to ˜58 K ( ˜37 K) around room temperature. Hydrostatic pressure measurements reveal a strong increase of threshold current with increasing pressure. This implies that current leakage dominates carrier recombination which is also responsible for their low T0 and T1 values at room temperature.
Development of computer program NAS3D using Vector processing for geometric nonlinear analysis of structures
NASA Technical Reports Server (NTRS)
Mangalgiri, P. D.; Prabhakaran, R.
An algorithm for vectorized computation of stiffness matrices of an 8 noded isoparametric hexahedron element for geometric nonlinear analysis was developed. This was used in conjunction with the earlier 2-D program GAMNAS to develop the new program NAS3D for geometric nonlinear analysis. A conventional, modified Newton-Raphson process is used for the nonlinear analysis. New schemes for the computation of stiffness and strain energy release rates is presented. The organization the program is explained and some results on four sample problems are given. The study of CPU times showed that savings by a factor of 11 to 13 were achieved when vectorized computation was used for the stiffness instead of the conventional scalar one. Finally, the scheme of inputting data is explained.
Benefits of a Unified LaSRS++ Simulation for NAS-Wide and High-Fidelity Modeling
NASA Technical Reports Server (NTRS)
Glaab, Patricia; Madden, Michael
The LaSRS++ high-fidelity vehicle simulation was extended in 2012 to support a NAS-wide simulation mode. Since the initial proof-of-concept, the LaSRS++ NAS-wide simulation is maturing into a research-ready tool. A primary benefit of this new capability is the consolidation of the two modeling paradigms under a single framework to save cost, facilitate iterative concept testing between the two tools, and to promote communication and model sharing between user communities at Langley. Specific benefits of each type of modeling are discussed along with the expected benefits of the unified framework. Current capability details of the LaSRS++ NAS-wide simulations are provided, including the visualization tool, live data interface, trajectory generators, terminal routing for arrivals and departures, maneuvering, re-routing, navigation, winds, and turbulence. The plan for future development is also described.
, EPUSP, Brasil, 1989 Carina Barros Mello, Doutora, INPE, Brasil, 2011 Chen Ying An, Doutor, ITA, Brasil, Doutor, USP, Brasil, 1990 Evaldo José Corat, Doutor, ITA, Brasil, 1993 Luiz Ângelo Berni, Doutor, UNICAMP, Brasil, 1996 Maria do Carmo de Andrade Nono, Doutora, ITA, Brasil, 1990 Mario Ueda, Doutor, Cornell, E
Concentração Walter Abrahão dos Santos Docentes Permanentes Ana Maria Ambrosio, Doutora, INPE, Brasil, 2005, 1993 Joaquim José Barroso de Castro, Doutor, INPE, Brasil, 1988 José Osvaldo Rossi, Ph.D., University of Oxford, Inglaterra,1998 Luis Antonio Waack Bambace, Doutor, INPE, Brasil, 2005 Maria de Fátima Mattiello
, EPUSP, Brasil, 1989 Chen Ying An, Doutor, ITA, Brasil, 1998 Eduardo Abramof, Doutor, Univ. Johannes Silva, Doutor, USP, Brasil, 1990 Evaldo José Corat, Doutor, ITA, Brasil, 1993 Luiz Ângelo Berni, Doutor, UNICAMP, Brasil, 1996 Maria do Carmo de Andrade Nono, Doutora, ITA, Brasil, 1990 Mario Ueda, Doutor
Concentração Maria do Carmo de Andrade Nono Docentes Permanentes Ana Maria Ambrosio, Doutora,INPE, Brasil, 2005, 1993 Joaquim José Barroso de Castro, Doutor, INPE, Brasil, 1988 José Osvaldo Rossi, Ph.D., University of Oxford, Inglaterra,1998 Luis Antonio Waack Bambace, Doutor,INPE, Brasil, 2005 Maurício Gonçalves Vieira
Concentração Ana Maria Ambrosio Docentes Permanentes Ana Maria Ambrosio, Doutora,INPE, Brasil, 2005 Geilson José Barroso de Castro, Doutor, INPE, Brasil, 1988 José Osvaldo Rossi, Ph.D., University of Oxford, Inglaterra,1998 Luis Antonio Waack Bambace, Doutor,INPE, Brasil, 2005 Maurício Gonçalves Vieira Ferreira
Concentração Ana Maria Ambrosio Docentes Permanentes Ana Maria Ambrosio, Doutora, INPE, Brasil, 2005 Geilson José Barroso de Castro, Doutor, INPE, Brasil, 1988 José Osvaldo Rossi, Ph.D., University of Oxford, Inglaterra,1998 Luis Antonio Waack Bambace, Doutor, INPE, Brasil, 2005 Maurício Gonçalves Vieira Ferreira
MBE growth of InAs self-assembled quantum dots embedded in GaNAs strain-compensating layers
Takayuki Hashimoto; Ryuji Oshima; Hidemi Shigekawa; Yoshitaka Okada
We fabricated self-assembled InAs quantum dots (QDs) embedded with a combined set of a GaNAs strain-compensating layer (SCL) and an InGaAs strain-reducing layer (SRL) by using atomic hydrogen-assisted molecular beam epitaxy (H-MBE) with a RF plasma nitrogen source. By inserting an InGaAs SRL between the InAs QD layer and GaNAs SCL, we were able to achieve a significant improvement of
High modal gain in Ga(NAsP)/(BGa)((As)P) heterostructures grown lattice matched on (001) silicon
NASA Astrophysics Data System (ADS)
Koukourakis, N.; Funke, D. A.; Gerhardt, N. C.; Hofmann, M. R.; Liebich, S.; Bückers, C.; Zinnkann, S.; Zimprich, M.; Beyer, A.; Chatterjee, S.; Koch, S. W.; Kunert, B.; Volz, K.; Stolz, W.
We present modal gain measurements in Ga(NAsP) heterostructures pseudomorphically grown on silicon substrate. Using the variable stripe length method we analyze the modal gain performance of an unprocessed single quantum well sample for different excitation densities. We obtain high modal gain values up to 55 cm-1 at room temperature. These values are comparable to those of common high quality laser material. This demonstrates the high optical quality of the new dilute nitride material Ga(NAsP) and underlines its candidacy for electrically pumped lasing on silicon substrate.
Lasing Characteristics of Low-Threshold GaInNAs Lasers Grown by Metalorganic Chemical Vapor Deposition
Masao Kawaguchi; Tomoyuki Miyamoto; Eric Gouardes; Dietmar Schlenker; Takashi Kondo; Fumio Koyama; Kenichi Iga
We report on the lasing characteristics of low-threshold long-wavelength GaInNAs double quantum well (DQW) lasers grown by metalorganic chemical vapor deposition (MOCVD). We have achieved a threshold current density of 450 A\\/cm2 for a 1.28-mum-emitting laser. This is the lowest value for 1.3-mum-range GaInNAs lasers grown by MOCVD@. We also observed high characteristic temperatures (T0) of 210 K and 130
Efficient GaInNAs Gain Mirrors for Semiconductor Disk Lasers at 1.18 {mu}m and 1.22 {mu}m
Korpijaervi, Ville-Markus; Puustinen, Janne; Leinonen, Tomi; Rautiainen, Jussi; Haerkoenen, Antti; Hakkarainen, Teemu; Guina, Mircea [Optoelectronics Research Centre, Tampere University of Technology, P.O. Box 692, FIN-3310, Tampere (Finland)
We report two GaInNAs/GaAs semiconductor disk lasers emitting at the wavelengths of 1180 nm and 1220 nm. The lasers generated 5 W and 7 W output powers, respectively, at a mount temperature of 15 deg. C. Both the gain mirrors were grown by molecular beam epitaxy and consisted of a GaAs/AlAs distributed Bragg reflector and an active region with 10 GaInNAs/GaNAs/GaAs QWs.
Assessment of microscopic lattice structures in dilute (AlGaIn)NAs laser materials by local mode spectroscopy and numerical simulations
NASA Astrophysics Data System (ADS)
Talwar, D. N.
In the framework of a rigid-ion model we report the results of a comprehensive Green's function analyses of the Fourier transform infrared (FTIR) absorption and Raman scattering data on localized vibrational modes (LVMs) to investigate the microscopic lattice structures related with the nitrogen incorporation in (AlGaIn)NAs alloys. Contrary to the outcome of a recent FTIR report of LVMs on GaInNAs multiple-quantum well structures, our group-theoretical analyses of impurity vibrations support the earlier IR and Raman scattering experiments providing corroboration to the fact that upon annealing and/or by increasing In(Al) composition in GaIn(Al)NAs there occur structural changes causing N environment to transform from NAsGa4 to NAsIn(Al)Ga3 and/or NAsIn2(Al2)Ga2 microstructures. From the force variation correlation with bond covalency for the closest mass acceptor CAs(a-) and isoelectronic NAs(i) defects in GaAs we have obtained the corrected value of u for Al-N bond predicting NAs local mode in AlAs (~510 cm-1) at a higher frequency than that of GaAs:N (471 cm-1). Theoretical results of impurity modes for Al-N complexes in GaAlNAs are compared and discussed with the existing Raman data.
Coupling fuel-constrained power plant and NaS battery system for profit increment in a competitive electricity market
S. Jalal Kazempour; Majid Hosseinpour; Mohsen Parsa Moghaddam; G. R. Yousefi
This work introduces coupling fuel-constrained power plant and electric energy storage plant aim to overall profit increment in a restructured electricity market. Among electric energy storage technologies, we select NaS battery (Natrium Sulfur battery) systems for coupling with power plant because of their enough technological maturation and less environmental impacts. The goal is investigating the coupling efficiency on profit increment
BASS' NK GROUPS AND cdh-FIBRANT HOCHSCHILD G. CORTI~NAS, C. HAESEMEYER, MARK E. WALKER, AND C. WEIBEL
Weibel, Charles
BASS' NK GROUPS AND cdh-FIBRANT HOCHSCHILD HOMOLOGY. G. CORTI~NAS, C. HAESEMEYER, MARK E. WALKER and the cohomology of K¨ahler differentials for the cdh topology. We use this to address Bass' question, whether Kn is essentially of finite type over the complex numbers, but negative in general. In 1972, H. Bass posed
Proceedings of Institute of Mathematics of NAS of Ukraine 2002, Vol. 43, Part 1, 252255 Transformation of Scientific System
Popovych, Roman
Proceedings of Institute of Mathematics of NAS of Ukraine 2002, Vol. 43, Part 1, 252 Physics Alla VOROBYOVA Mykolayiv Pedagogical University, Mykolayiv, Ukraine E-mail: alla on application of symmetry methods to partial differential equations. There is some advancement in Ukraine
Proceedings of Institute of Mathematics of NAS of Ukraine 2002, Vol. 43, Part 2, 461465 On Four Orthogonal Projections
Popovych, Roman
Proceedings of Institute of Mathematics of NAS of Ukraine 2002, Vol. 43, Part 2, 461Â465 On Four and Anatolii KYRYCHENKO National Academy of Security Service of Ukraine, Kyiv, Ukraine Kyiv National University of Building and Architecture, 31 Povitroflotsky Prosp., Kyiv 03037, Ukraine E-mail: AAKirichenko
Proceedings of Institute of Mathematics of NAS of Ukraine 2002, Vol. 43, Part 2, 652658 Canonical Realization of Poincare Algebra
Popovych, Roman
Proceedings of Institute of Mathematics of NAS of Ukraine 2002, Vol. 43, Part 2, 652Â658 Canonical for Condensed Matter Physics of the National Academy of Sciences of Ukraine, 1 Svientsitskii Str., 79011 Lviv, Ukraine E-mail: firstname.lastname@example.com The canonical realization of the Poincar´e group for the systems
National Academy of Sciences (NAS) Study entitled The Effect of Climate Change on Indoor Air Quality and Public Health.
The Institute of Medicine of the NAS is conducting a study to evaluate the state of scientific understanding of the effects of climate change on indoor air quality and public health. General topics may include the likely impacts of climate change in the U.S. on the indoor environ...
Right and Wrong and Cultural Diversity: Replication of the 2002 NAS/Zogby Poll on Business Ethics
ERIC Educational Resources Information Center
Ludlum, Marty; Mascaloinov, Sergei
In April 2002, a NAS/Zogby poll found that only a quarter of sampled students perceived uniform standards of "right and wrong" and that most students felt that ethical behavior depends on cultural diversity. In this effort to replicate those findings in a larger sample of American college students, the authors obtained results that contradict the…
1-eV GaInNAs solar cells for ultrahigh-frequency multijunction devices
Friedman, D.J.; Geisz, J.F.; Kurtz, S.R.; Olson, J.M. [National Renewable Energy Lab., Golden, CO (United States)
The authors demonstrate working prototypes of a GaInNAs-based solar cell lattice-matched to GaAs with photoresponse down to 1 eV. This device is intended for use as the third junction of future-generation ultrahigh-efficiency three- and four-junction devices. Under the AM1.5 direct spectrum with all the light higher in energy than the GaAs band gap filtered out, the prototypes have open-circuit voltages ranging from 0.35 to 0.44 V, short-circuit currents of 1.8 mA/cm{sup 2}, and fill factors from 61--66%. The short-circuit currents are of principal concern: the internal quantum efficiencies rise only to about 0.2. The authors discuss the short diffusion lengths which are the reason for this low photocurrent. As a partial workaround for the poor diffusion lengths, they demonstrate a depletion-width-enhanced variation of one of the prototype devices that grades off decreased voltage for increased photocurrent, with a short-circuit current of 6.5 mA/cm{sup 2} and an open-circuit voltage of 0.29 V.
Proceedings of Institute of Mathematics of NAS of Ukraine 2004, Vol. 50, Part 1, 271276 On Applications of Non-Point
Popovych, Roman
Proceedings of Institute of Mathematics of NAS of Ukraine 2004, Vol. 50, Part 1, 271., Bialystok, Poland; Intitute of Geophysics of NAS of Ukraine, 32 Palladina Ave., 03142 Kyiv-142, Ukraine E-94, Ukraine E-mail: firstname.lastname@example.com Combination of non-point and conditional symmetries
Proceedings of Institute of Mathematics of NAS of Ukraine 2004, Vol. 50, Part 3, 12141218 On Certain Quotient of TemperleyLieb Algebra
Popovych, Roman
Proceedings of Institute of Mathematics of NAS of Ukraine 2004, Vol. 50, Part 3, 1214Â1218 On Certain Quotient of TemperleyÂLieb Algebra Mariya O. VLASENKO Institute of Mathematics of NAS Ukraine, 3 Tereshchenkivs'ka Str., 01601 Kyiv-4, Ukraine E-mail: email@example.com We consider a certain quotient
Proceedings of Institute of Mathematics of NAS of Ukraine 2004, Vol. 50, Part 1, 3439 Solitary Wave Solutions for Heat Equations
Nikitin, Anatoly
Proceedings of Institute of Mathematics of NAS of Ukraine 2004, Vol. 50, Part 1, 34Â39 Solitary Pedagogical University, 2 Ostrogradsky Str., 36003 Poltava, Ukraine E-mail: email@example.com Institute of Mathematics of NAS of Ukraine, 3 Tereshchenkivs'ka Str., 01601 Kyiv-4, Ukraine E-mail: nikitin
Proceedings of Institute of Mathematics of NAS of Ukraine 2002, Vol. 43, Part 2, 486489 On One Algebra of TemperleyLieb Type
Popovych, Roman
Proceedings of Institute of Mathematics of NAS of Ukraine 2002, Vol. 43, Part 2, 486Â489 On One Algebra of TemperleyÂLieb Type Nataly POPOVA Institute of Mathematics of the NAS of Ukraine, 3 Tereshchenkivska Str., 01601 Kyiv-4, Ukraine E-mail: popova firstname.lastname@example.com An algebra generated by projections
Proceedings of Institute of Mathematics of NAS of Ukraine 2004, Vol. 50, Part 3, 13081313 On the BBGKY Hierarchy Solutions for Many-
Popovych, Roman
Proceedings of Institute of Mathematics of NAS of Ukraine 2004, Vol. 50, Part 3, 1308 , T.V. RYABUKHA , M.O. STASHENKO Institute of Mathematics of NAS of Ukraine, 3 Tereshchenkivs'ka Str., 01601 Kyiv-4, Ukraine E-mail: firstname.lastname@example.com, email@example.com Volyn State University, 13
Proceedings of Institute of Mathematics of NAS of Ukraine 2004, Vol. 50, Part 3, 10641070 On 2 + 2 Locally Compact Quantum Groups
Popovych, Roman
Proceedings of Institute of Mathematics of NAS of Ukraine 2004, Vol. 50, Part 3, 1064Â1070 On 2 + 2 of Mathematics of NAS Ukraine, 3 Tereshchenkivs'ka Str., 01601 Kyiv-4, Ukraine E-mail: firstname.lastname@example.com, firstname.lastname@example.com Institute of Applied System Analysis, National Technical University of Ukraine ("KPI"), 37 Pobedy Ave
Proceedings of Institute of Mathematics of NAS of Ukraine 2002, Vol. 43, Part 1, 140144 On Differential Invariants of First-and Second-Order
Popovych, Roman
Proceedings of Institute of Mathematics of NAS of Ukraine 2002, Vol. 43, Part 1, 140 and Mathematics of NAS of Ukraine, 3b Naukova Str., Lviv 79601, Ukraine E-mail: vas email@example.com Franko Lviv National University, 1 Universytetska Str., Lviv 79000, Ukraine E-mail: fedorchukv
Proceedings of Institute of Mathematics of NAS of Ukraine 2000, Vol. 30, Part 1, 204209. One-Dimensional FokkerPlanck Equation Invariant
Popovych, Roman
Proceedings of Institute of Mathematics of NAS of Ukraine 2000, Vol. 30, Part 1, 204Â209. One STOGNII Institute of Mathematics of NAS of Ukraine, 3 Tereshchenkivska Street, Kyiv, Ukraine E-mail: firstname.lastname@example.com National Technical University of Ukraine "Kyiv Polytechnic Institute
Proceedings of Institute of Mathematics of NAS of Ukraine 2002, Vol. 43, Part 2, 466468 Realizations of Real 4-Dimensional Solvable
Popovych, Roman
Proceedings of Institute of Mathematics of NAS of Ukraine 2002, Vol. 43, Part 2, 466 Institute of Mathematics of NAS of Ukraine, 3 Tereshchenkivska Str., Kyiv 4, Ukraine E-mail: firstname.lastname@example.com Poltava State Pedagogical University, 2 Ostrogradskoho Str., Poltava, Ukraine E-mail: firstname.lastname@example.com We
Proceedings of Institute of Mathematics of NAS of Ukraine 2004, Vol. 50, Part 1, 125130 Symmetry Classification of KdV-Type
Popovych, Roman
Proceedings of Institute of Mathematics of NAS of Ukraine 2004, Vol. 50, Part 1, 125Â130 Symmetry Poltava, Ukraine E-mail: firstname.lastname@example.com, firstname.lastname@example.com § Institute of Mathematics of NAS Ukraine, 3 Tereschenkivs'ka Str., 01601 Kyiv-4, Ukraine E-mail: email@example.com This paper
Proceedings of Institute of Mathematics of NAS of Ukraine 2000, Vol. 30, Part 2, 516523. Weyl-Type Quantization Rules and N-Particle
Popovych, Roman
Proceedings of Institute of Mathematics of NAS of Ukraine 2000, Vol. 30, Part 2, 516Â523. Weyl-Time V. SHPYTKO Institute for Condensed Matter Physics of NAS of Ukraine, 1 Svientsitskii Str., Lviv, Ukraine EÂmail: email@example.com Quantization of canonical realization of the Poincar´e algebra p(1, 1
Proceedings of Institute of Mathematics of NAS of Ukraine 2004, Vol. 50, Part 1, 298303 Sets of Conditional Symmetry Operators and Exact
Popovych, Roman
Proceedings of Institute of Mathematics of NAS of Ukraine 2004, Vol. 50, Part 1, 298Â303 Sets and Alla VOROBYOVA Institute of Mathematics of NAS Ukraine, 3 Tereshchenkivs'ka Str., 01601 Kyiv-4, Ukraine E-mail: firstname.lastname@example.com Mykolayiv Petro Mogyla State Humanities University, Mykolaiv
Proceedings of Institute of Mathematics of NAS of Ukraine 2004, Vol. 50, Part 3, 14481453 Quantum Phase Space in Relativistic Theory
Popovych, Roman
Proceedings of Institute of Mathematics of NAS of Ukraine 2004, Vol. 50, Part 3, 1448Â1453 Quantum and C.V. USENKO Institute of Physics of NAS of Ukraine, 46 Nauky Ave., 03028 Kyiv, Ukraine E-mail: sem., 03127 Kyiv, Ukraine E-mail: firstname.lastname@example.com Mathematical method of quantum phase space is very
Proceedings of Institute of Mathematics of NAS of Ukraine 2004, Vol. 50, Part 1, 4046 The Structure of Lie Algebras and the Classification
Popovych, Roman
Proceedings of Institute of Mathematics of NAS of Ukraine 2004, Vol. 50, Part 1, 40 Poltava, Ukraine E-mail: firstname.lastname@example.com, email@example.com § Institute of Mathematics of NAS Ukraine, 3 Tereshchenkivs'ka Str., 01601 Kyiv-4, Ukraine E-mail: email@example.com We have
Proceedings of Institute of Mathematics of NAS of Ukraine 2002, Vol. 43, Part 1, 1724 Mykhailo Vasyl'ovych Ostrohrads'kyi
Popovych, Roman
Proceedings of Institute of Mathematics of NAS of Ukraine 2002, Vol. 43, Part 1, 17Â24 Mykhailo Vasyl'ovych Ostrohrads'kyi Anatoly M. SAMOILENKO Institute of Mathematics of NAS of Ukraine, 3 Tereshchenkivska Str., 01601 Kyiv-4, Ukraine E-mail: firstname.lastname@example.com The paper describes life and research
Proceedings of Institute of Mathematics of NAS of Ukraine 2004, Vol. 50, Part 3, 12361243 Regularity Properties of Infinite-Dimensional
Popovych, Roman
Proceedings of Institute of Mathematics of NAS of Ukraine 2004, Vol. 50, Part 3, 1236 Vict. ANTONIOUK Institute of Mathematics of NAS Ukraine, 3 Tereshchenkivs'ka Str., 01601 Kyiv-4, Ukraine E-mail: firstname.lastname@example.com In this paper we discuss the C properties of evolution
Laser Gain and Threshold Properties in Compressive-Strained and Lattice-Matched GaInNAs/GaAs Quantum Wells
Chow, W.W.; Jones, E.D.; Modine, N.A.; Allerman, A.A.; Kurtz, S.R.
The optical gain spectra for compressive-strained and lattice-matched GaInNAs/GaAs quantum wells are computed using a microscopic laser theory. From these spectra, the peak gain and carrier radiative decay rate as functions of carrier density are determined. These dependences allow the study of lasing threshold current density for different GAInNAs/GaAs laser structures.
On Ensino de Astronomia nas Cidades de Ribeirão Pires e Rio Grande da Serra
NASA Astrophysics Data System (ADS)
Faria, R. Z.; Voelzke, M. R.
Apesar da astronomia ser um dos temas indicados pelos Parâmetros Curriculares Nacionais, observa-se que poucas mudanças ocorreram desde a implementação do mesmo em sala de aula. A presente pesquisa diz respeito sobre como os tópicos de astronomia estão sendo abordados pelos professores no ensino médio. Optou-se por aplicar um questionário com os professores que ministram a disciplina de física. Os mesmos trabalham em escolas estaduais situadas nas cidades de Ribeirão Pires e Rio Grande da Serra, ambas subordinadas a Diretoria de Ensino de Mauá, no Estado de São Paulo. O questionário foi aplicado durante o 2° semestre de 2006. Até o momento os resultados são preliminares. Dos 82,0% dos professores que responderam ao questionário no município de Rio Grande da Serra, 66,7% não aplicaram nenhum tópico de astronomia, 77,8% não utilizaram qualquer tipo de programa computacional, 66,7% não utilizaram laboratório, que 77,8% nunca levaram os alunos a museus e ou planetários e que 66,7% não indicaram qualquer tipo de revista ou livro sobre astronomia aos seus alunos. No município de Ribeirão Pires, 53,3% dos professores responderam ao questionário, destes 75,0% não aplicaram nenhum tópico de astronomia, 93,8% não utilizaram qualquer tipo de programa computacional, 75,0% não utilizaram laboratório, 81,3% nunca levaram os alunos a museus e ou planetário e 56,3% não indicaram qualquer tipo de revista ou livro sobre astronomia ao seus alunos. Apesar da maioria dos professores reconhecerem que o conteúdo de astronomia influi na formação do jovem, os mesmos não incluem o tema em seus planejamentos escolares.
Investigations of (GaIn)(NAs) bulk layers and (GaIn)(NAs)\\/GaAs multiple quantum well structures grown using tertiarybutylarsine (TBAs) and 1,1-dimethylhydrazine (UDMHy)
F. Höhnsdorf; J. Koch; C. Agert; W. Stolz
The optimization of the metalorganic vapour phase epitaxial (MOVPE) growth of lattice-matched (GaIn)(NAs)\\/GaAs multiple quantum well (MQW) structures grown by using triethylgallium (TEGa) and trimethylindium (TMIn) in combination with tertiarybutyl arsine (TBAs) and 1,1-dimethylhydrazine (UDMHy) is investigated in detail by means of high resolution X-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM) as well as photoluminescence (PL)
Joyse Tatiane Souza dos Santos; Heriberto Wagner Amanajás Pena
O geoprocessamento é uma importante ferramenta para se compreender a estrutura e a dinâmica das paisagens em diversas escalas temporais e espaciais, quando aplicado à ecologia de paisagem traz elementos tanto para o estudo das interações do homem com o meio ambiente, quanto para compreender os processos ecológicos. Dessa forma objetiva-se com este artigo, levantar as situações ambientais associadas à
Fluidized Bed Steam Reformer (FBSR) Na-AI-SI (NAS) Waste Form for Hanford LAW and Secondary Waste
Jantzen, C.; Pierce, E.
FBSR sodium-aluminosilicate (NAS) waste form has been identified as a promising supplemental treatment technology for Hanford LAW and/or Waste Treatment Plant Secondary Waste (WTP-SW). Objectives of the project: 1) Prove the robustness of FBSR as a waste form for either LAW and/or WTP-SW; 2) Reduce the risk associated with implementing the FBSR NAS waste form as a supplemental treatment technology for Hanford LAW and/or WTP-SW; 3) Conduct two treatability studies with SRS radioactive wastes that have been shimmed to look like Hanford WTP-SW and LAW; 4) Conduct three treatability studies with actual Hanford tank wastes; 5) Fill key data gaps; 6) Link previous and new results together.
NASA's UAS Integration into the NAS: A Report on the Human Systems Integration Phase 1 Simulation Activities
NASA Technical Reports Server (NTRS)
Fern, Lisa; Rorie, R. Conrad; Shively, R. Jay
In 2011 the National Aeronautics and Space Administration (NASA) began a five-year Project to address the technical barriers related to routine access of Unmanned Aerial Systems (UAS) in the National Airspace System (NAS). Planned in two phases, the goal of the first phase was to lay the foundations for the Project by identifying those barriers and key issues to be addressed to achieve integration. Phase 1 activities were completed two years into the five-year Project. The purpose of this paper is to review activities within the Human Systems Integration (HSI) subproject in Phase 1 toward its two objectives: 1) develop GCS guidelines for routine UAS access to the NAS, and 2) develop a prototype display suite within an existing Ground Control Station (GCS). The first objective directly addresses a critical barrier for UAS integration into the NAS - a lack of GCS design standards or requirements. First, the paper describes the initial development of a prototype GCS display suite and supporting simulation software capabilities. Then, three simulation experiments utilizing this simulation architecture are summarized. The first experiment sought to determine a baseline performance of UAS pilots operating in civil airspace under current instrument flight rules for manned aircraft. The second experiment examined the effect of currently employed UAS contingency procedures on Air Traffic Control (ATC) participants. The third experiment compared three GCS command and control interfaces on UAS pilot response times in compliance with ATC clearances. The authors discuss how the results of these and future simulation and flight-testing activities contribute to the development of GCS guidelines to support the safe integration of UAS into the NAS. Finally, the planned activities for Phase 2, including an integrated human-in-the-loop simulation and two flight tests are briefly described.
Optimization of Growth of GaInNAs Dilute Nitrides for Multi-junction Solar Cell Applications
Yukiko Shimizu; Naoya Miyashita; Yusuke Mura; Akira Uedono; Yoshitaka Okada
We have investigated the effect of growth temperature on the final crystal quality of GaInNAs solar cells in atomic hydrogen-assisted molecular beam epitaxy (H-MBE). A higher growth temperature of ~500degC has been found to be the optimum and resulted in both improved crystal quality and solar cell performance. The photoluminescence (PL) peak intensity was one order of magnitude stronger and
Unmanned Aircraft Systems (UAS) Integration in the National Airspace System (NAS) Project - Gen-4 and Gen-5 Radio Plans
NASA Technical Reports Server (NTRS)
Griner, James H.
NASA's UAS Integration in the NAS project, has partnered with Rockwell Collins to develop a concept Control and Non-Payload Communication (CNPC) system prototype radio, operating on recently allocated UAS frequency spectrum bands. This prototype radio is being used to validate initial proposed performance requirements for UAS control communications. This presentation will give an overview of the current plans for the prototype radio development.
Electron-irradiation enhanced photoluminescence from GaInNAs\\/GaAs quantum wells subject to thermal annealing
E.-M. Pavelescu; A. Gheorghiu; M. Dumitrescu; A. Tukiainen; T. Jouhti; T. Hakkarainen; R. Kudrawiec; J. Andrzejewski; J. Misiewicz; N. Tkachenko; H. Lemmetyinen; M. Pessa
Electron irradiation of a 1.3-mum-GaInNAs\\/GaAs multi-quantum-well heterostructure, grown by molecular beam epitaxy and subsequently rapid-thermal annealed, is found to induce much stronger photoluminescence than what is observed for an identical as-grown sample upon annealing. Annealing of the irradiated sample also causes a small additional spectral blueshift and reduces alloy potential energy fluctuations at the conduction band minimum. These irradiation-related phenomena
Nitrogen-concentration control in GaNAs/AlGaAs quantum wells using nitrogen ?-doping technique
Mano, Takaaki; Jo, Masafumi; Kuroda, Takashi; Noda, Takeshi; Sugimoto, Yoshimasa; Sakuma, Yoshiki [National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047 (Japan); Elborg, Martin; Sakoda, Kazuaki [National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047, Japan and Graduate School of Pure and Applied Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577 (Japan)
GaNAs/Al{sub 0.35}Ga{sub 0.65}As multiple quantum wells (MQWs) with nitrogen ?-doping were fabricated on GaAs (100) substrates by plasma-assisted molecular beam epitaxy. High controllability of nitrogen-concentrations in the MQWs was achieved by tuning nitrogen ?-doping time. The maximum nitrogen concentration in the MQWs was 2.8%. The MQWs exhibit intense, narrow photoluminescence emission.
Suppression of non-radiative surface recombination by N incorporation in GaAs/GaNAs core/shell nanowires
Chen, Shula L.; Chen, Weimin M.; Ishikawa, Fumitaro; Buyanova, Irina A.
III-V semiconductor nanowires (NWs) such as GaAs NWs form an interesting artificial materials system promising for applications in advanced optoelectronic and photonic devices, thanks to the advantages offered by the 1D architecture and the possibility to combine it with the main-stream silicon technology. Alloying of GaAs with nitrogen can further enhance performance and extend device functionality via band-structure and lattice engineering. However, due to a large surface-to-volume ratio, III-V NWs suffer from severe non-radiative carrier recombination at/near NWs surfaces that significantly degrades optical quality. Here we show that increasing nitrogen composition in novel GaAs/GaNAs core/shell NWs can strongly suppress the detrimental surface recombination. This conclusion is based on our experimental finding that lifetimes of photo-generated free excitons and free carriers increase with increasing N composition, as revealed from our time-resolved photoluminescence (PL) studies. This is accompanied by a sizable enhancement in the PL intensity of the GaAs/GaNAs core/shell NWs at room temperature. The observed N-induced suppression of the surface recombination is concluded to be a result of an N-induced modification of the surface states that are responsible for the nonradiative recombination. Our results, therefore, demonstrate the great potential of incorporating GaNAs in III-V NWs to achieve efficient nano-scale light emitters. PMID:26100755
Temperature dependence investigation of the electron paramagnetic resonance of the photorefractive polymer BisA-NAS:DEH
NASA Astrophysics Data System (ADS)
Darwish, Abdalla M.; Kukhtarev, Nickolai V.; Copeland, Robert R.; Sliz, R.; Venkateswarlu, Putcha; Williams, Alton; Caulfield, H. John; Ducharme, Stephen; Takacs, James M.; Zhang, Lei
The photorefractive BisA-NitroAminoStilbene polymer (BisA- NAS:DEH) has drawn much attention in recent years due to its potential applications such as terabyte optical data storage, real time optical processing, image amplification, and dynamic holography. Extensive optical investigation for this polymer was performed mostly at room temperature. On the other hand less attention was given to the behavior of this polymer at much higher or lower temperatures than the room temperature. Using the electron paramagnetic resonance technique and a home built temperature controller (minus 190 to 500 degrees Celsius) we have been able to study the temperature effect on the spin concentration of BisA-NAS:DEH in the temperature range from 100 to minus 190 degrees Celsius. An anomalous behavior for the EPR signal was observed near 70 degrees Celsius as the spin density increases drastically especially around 85 degrees Celsius. Also, around minus 25 degrees Celsius the main EPR signal broadened then splits into a doublets which are quenched at higher temperatures. Preliminary interpretation of this signal is given on the basis of behavior of the NAS dye molecule at higher temperature and the transport agent DEH which transfers the charge generated at the dye molecule to the other part of the material, and thus coupling the process of photoconduction.
The structure of the NasR transcription antiterminator reveals a one-component system with a NIT nitrate receptor coupled to an ANTAR RNA-binding effector.
Boudes, Marion; Lazar, Noureddine; Graille, Marc; Durand, Dominique; Gaidenko, Tatiana A; Stewart, Valley; van Tilbeurgh, Herman
The nitrate- and nitrite-sensing NIT domain is present in diverse signal-transduction proteins across a wide range of bacterial species. NIT domain function was established through analysis of the Klebsiella oxytoca NasR protein, which controls expression of the nasF operon encoding enzymes for nitrite and nitrate assimilation. In the presence of nitrate or nitrite, the NasR protein inhibits transcription termination at the factor-independent terminator site in the nasF operon transcribed leader region. We present here the crystal structure of the intact NasR protein in the apo state. The dimeric all-helical protein contains a large amino-terminal NIT domain that associates two four-helix bundles, and a carboxyl-terminal ANTAR (AmiR and NasR transcription antitermination regulator) domain. The analysis reveals unexpectedly that the NIT domain is structurally similar to the periplasmic input domain of the NarX two-component sensor that regulates nitrate and nitrite respiration. This similarity suggests that the NIT domain binds nitrate and nitrite between two invariant arginyl residues located on adjacent alpha helices, and results from site-specific mutagenesis showed that these residues are critical for NasR function. The resulting structural movements in the NIT domain would provoke an active configuration of the ANTAR domains necessary for specific leader mRNA binding. PMID:22690729
Metalorganic chemical vapor deposition of GaInNAs lattice matched to GaAs for long-wavelength laser diodes
Shunichi Sato; Shiro Satoh
The crystal growth of GaInNAs lattice matched to GaAs by metalorganic chemical vapor deposition using dimethylhydrazine as the nitrogen source is described for realizing long-wavelength laser diodes. It was found that the crystalline quality of GaInNAs on AlGaAs is improved by inserting a GaAs spacer layer between GaInNAs and AlGaAs. The photoluminescence spectra of GaAs\\/Ga0.9In0.1NyAs1?y\\/GaAs-DH was measured at room temperature
Proceedings of Institute of Mathematics of NAS of Ukraine 2000, Vol. 30, Part 1, 180183. On SO(3)-Partially Invariant Solutions
Popovych, Roman
Proceedings of Institute of Mathematics of NAS of Ukraine 2000, Vol. 30, Part 1, 180Â183. On SO(3 of Ukraine, 3 Tereshchenkivska Street, Kyiv, Ukraine SO(3)-partially invariant solutions having minimal
Proceedings of Institute of Mathematics of NAS of Ukraine 2000, Vol. 30, Part 2, 387391. PP-Test for Integrability of Some Evolution
Popovych, Roman
Proceedings of Institute of Mathematics of NAS of Ukraine 2000, Vol. 30, Part 2, 387Â391. PP of the National Academy of Sciences of Ukraine, 3 Tereshchenkivs'ka Str., Kyiv, Ukraine The connection between
1.55 {mu}m GaAs/GaNAsSb/GaAs optical waveguides grown by radio frequency nitrogen plasma-assisted molecular beam epitaxy
Tan, K. H.; Yoon, S. F.; Loke, W. K.; Wicaksono, S.; Xu, Z.; Ng, T. K.; Lew, K. L. [School of Electrical and Electronic Engineering, Nanyang Technological University, Nanyang Avenue, Singapore 639798 (Singapore); Saadsaoud, N.; Zegaoui, M.; Decoster, D. [Institute of Electronics, Microelectronics and Nanotechnology (IEMN), UMR CNRS 8520, Universite des Sciences et Technologies de Lille BP 60069, 59652 Villeneuve d'Ascq Cedex (France); Chazelas, J. [Thales Airborne Systems, 2 Avenue Gay Lussac, 78852 Elancourt (France)
We demonstrate a 1.55 {mu}m GaAs/GaNAsSb/GaAs optical waveguide grown by molecular beam epitaxy as an alternative to the AlGaAs/GaAs system. The 0.4-{mu}m-thick GaNAsSb guiding layer contains {approx}3.5% of N and 9% of Sb, resulting in optical band gap of 0.88 eV. The refractive index of the GaNAsSb layer was measured from 800 to 1700 nm. The GaNAsSb layer has a refractive index value of 3.42 at 1.55 {mu}m wavelength. The propagation loss measured using the Fabry-Perot resonance method was found to be affected by nitrogen-related defect absorption.
High-voltage, low-current GaInP\\/GaInP\\/GaAs\\/GaInNAs\\/Ge solar cells
R. R. King; P. C. Colter; D. E. Joslin; K. M. Edmondson; D. D. Krut; N. H. Karam; S. Kurtz
Four-junction GaInP\\/GaAs\\/GaInNAs\\/Ge solar cells are a widely-pursued route toward AM0 efficiencies of 35% and above, and terrestrial efficiencies of up to 40%. Extensive research into the new material system of GaInNAs has so far yielded subcells with AM0 current densities far below the ?17 mA\\/cm2 needed to current match the other subcells in the stack. A new multijunction structure, a
Properties of 1.3 ?m InGaNAs laser material grown by MBE using a N 2\\/Ar RF plasma
J. A Gupta; P. J Barrios; G. C Aers; R. L Williams; J Ramsey; Z. R Wasilewski
InGaNAs single quantum well laser diodes were grown on GaAs substrates using solid-source molecular beam epitaxy with N2\\/Ar gas mixtures in an radio-frequency (RF) plasma cell. The structures employ GaNAs barriers which reduce the quantum confinement and extend the room temperature stimulated emission wavelength to 1.36 ?m. Test quantum well structures were grown with and without these barriers to demonstrate
Remotely Operated Aircraft (ROA) Impact on the National Airspace System (NAS) Work Package: Data Modeling and Sharing Perspective for Development of a Common Operating Picture
NASA Technical Reports Server (NTRS)
This report documents analyses that were performed in support of Task #3 of Work Package #3 (WP3), ROA Impact on the NAS. The purpose of the overall work package was to determine if there are any serious issues that would prevent or prohibit ROA's flying in the NAS on a routine basis, and if so, what actions should be taken to address them. The purpose of Task #3 was to look at this problem from the perspective of data modeling and sharing.
High gain 1.3-?m GaInNAs SOA with fast gain dynamics and enhanced temperature stability
NASA Astrophysics Data System (ADS)
Fitsios, D.; Giannoulis, G.; Iliadis, N.; Korpijärvi, V.-M.; Viheriälä, J.; Laakso, A.; Dris, S.; Spyropoulou, M.; Avramopoulos, H.; Kanellos, G. T.; Pleros, N.; Guina, M.
Semiconductor optical amplifiers (SOAs) are a well-established solution of optical access networks. They could prove an enabling technology for DataCom by offering extended range of active optical functionalities. However, in such costand energy-critical applications, high-integration densities increase the operational temperatures and require powerhungry external cooling. Taking a step further towards improving the cost and energy effectiveness of active optical components, we report on the development of a GaInNAs/GaAs (dilute nitride) SOA operating at 1.3?m that exhibits a gain value of 28 dB and combined with excellent temperature stability owing to the large conduction band offset between GaInNAs quantum well and GaAs barrier. Moreover, the characterization results reveal almost no gain variation around the 1320 nm region for a temperature range from 20° to 50° C. The gain recovery time attained values as short as 100 ps, allowing implementation of various signal processing functionalities at 10 Gb/s. The combined parameters are very attractive for application in photonic integrated circuits requiring uncooled operation and thus minimizing power consumption. Moreover, as a result of the insensitivity to heating issues, a higher number of active elements can be integrated on chip-scale circuitry, allowing for higher integration densities and more complex optical on-chip functions. Such component could prove essential for next generation DataCom networks.
Cohort Profile: The National Academy of Sciences-National Research Council Twin Registry (NAS-NRC Twin Registry).
Gatz, Margaret; Harris, Jennifer R; Kaprio, Jaakko; McGue, Matt; Smith, Nicholas L; Snieder, Harold; Spiro, Avron; Butler, David A
The National Academy of Sciences-National Research Council Twin Registry (NAS-NRC Twin Registry) is a comprehensive registry of White male twin pairs born in the USA between 1917 and 1927, both of the twins having served in the military. The purpose was medical research and ultimately improved clinical care. The cohort was assembled in the early 1960s with identification of approximately 16?000 twin pairs, review of service records, a brief mailed questionnaire assessing zygosity, and a health survey largely comparable to questionnaires used at that time with Scandinavian twin registries. Subsequent large-scale data collection occurred in 1974, 1985 and 1998, repeating the health survey and including information on education, employment history and earnings. Self-reported data have been supplemented with mortality, disability and medical data through record linkage. Potential collaborators should access the study website [http://www.iom.edu/Activities/Veterans/TwinsStudy.aspx] or e-mail the Medical Follow-up Agency at [email@example.com]. Questionnaire data are being prepared for future archiving with the National Archive of Computerized Data on Aging (NACDA) at the Inter-University Consortium for Political and Social Research (ICPSR), University of Michigan, MI. PMID:25183748
Three of Four GlnR Binding Sites Are Essential for GlnR-Mediated Activation of Transcription of the Amycolatopsis mediterranei nas Operon
Wang, Ying; Wang, Jing-Zhi; Shao, Zhi-Hui; Yuan, Hua; Lu, Yin-Hua; Jiang, Wei-Hong
In Amycolatopsis mediterranei U32, genes responsible for nitrate assimilation formed one operon, nasACKBDEF, whose transcription is induced by the addition of nitrate. Here, we characterized GlnR as a direct transcriptional activator for the nas operon. The GlnR-protected DNA sequences in the promoter region of the nas operon were characterized by DNase I footprinting assay, the previously deduced Streptomyces coelicolor double 22-bp GlnR binding consensus sequences comprising a1, b1, a2, and b2 sites were identified, and the sites were then mutated individually to test their roles in both the binding of GlnR in vitro and the GlnR-mediated transcriptional activation in vivo. The results clearly showed that only three GlnR binding sites (a1, b1, and b2 sites) were required by GlnR for its specific binding to the nas promoter region and efficient activation of the transcription of the nas operon in U32, while the a2 site seemed unnecessary. PMID:23543714
Remotely Operated Aircraft (ROA) Impact on the National Airspace System (NAS) Work Package, 2005: Composite Report on FAA Flight Plan and Operational Evaluation Plan. Version 7.0
NASA Technical Reports Server (NTRS)
The purpose of this document is to present the findings that resulted from a high-level analysis and evaluation of the following documents: (1) The OEP (Operational Evolution Plan) Version 7 -- a 10-year plan for operational improvements to increase capacity and efficiency in U.S. air travel and transport and other use of domestic airspace. The OEP is the FAA commitment to operational improvements. It is outcome driven, with clear lines of accountability within FAA organizations. The OEP concentrates on operational solutions and integrates safety, certification, procedures, staffing, equipment, avionics and research; (2) The Draft Flight Plan 2006 through 2010 -- a multi-year strategic effort, setting a course for the FAA through 2001, to provide the safest and most efficient air transportation system in the world; (3) The NAS System Architecture Version 5 -- a blueprint for modernizing the NAS and improving NAS services and capabilities through the year 2015; and (4) The NAS-SR-1000 System Requirements Specification (NASSRS) -- a compilation of requirements which describe the operational capabilities for the NAS. The analysis is particularly focused on examining the documents for relevance to existing and/or planned future UAV operations. The evaluation specifically focuses on potential factors that could materially affect the development of a commercial ROA industry, such as: (1) Design limitations of the CNS/ATM system, (2) Human limitations, The information presented was taken from program specifications or program office lead personnel.
Study of nitrogen incorporation into GaInNAs: The role of growth temperature in molecular beam epitaxy
Korpijaervi, V.-M.; Aho, A.; Tukiainen, A.; Laakso, A.; Guina, M. [Optoelectronics Research Centre (ORC), Tampere University of Technology, Tampere 33720 (Finland); Laukkanen, P.; Tuominen, M. [Department of Physics and Astronomy, University of Turku, Turku 20014 (Finland)
GaInNAs has an important impact on developing GaAs-based optoelectronics and multijunction solar cells, but the complex nature of the nitrogen incorporation into GaInAs is still not fully understood. By combining x-ray diffraction, photoluminescence, reflection high-energy electron diffraction, and photoelectron spectroscopy measurements, we show that nitrogen incorporation is enhanced with increasing growth temperature in the range of 300-450 Degree-Sign C. We study the growth front and show that the surface reconstruction is (1 Multiplication-Sign 3) regardless of growth temperature in this range. The enhanced nitrogen incorporation can be modeled as a thermally activated process with activation energy of about 0.1 eV.
High-temperature characteristic in 1.3-?m-range highly strained GaInNAs ridge stripe lasers grown by metal-organic chemical vapor deposition
Shunichi Sato; Shiro Satoh
1.3-?m-range highly strained GaInNAs-GaAs double quantum-well ridge stripe lasers with different In contents (37% and 39%) grown by metal-organic chemical vapor deposition are demonstrated. The GaInNAs laser with In content of 37% emitting at 1.294 ?m exhibited both a low threshold current density of 1.0 kA\\/cm2 at 20°C and a high characteristic temperature of 148 K in the temperature range
Effects of rapid thermal annealing conditions on GaInNAs band gap blueshift and photoluminescence intensity
Liverini, V.; Rutz, A.; Keller, U.; Schoen, S. [ETH Zurich, Physics Department, Institute of Quantum Electronics, Wolfgang-Pauli-Strasse 16, CH-8093 Zurich (Switzerland); ETH Zurich, FIRST Center for Micro- and Nanoscience, Wolfgang-Pauli-Strasse 10, CH-8093 Zurich (Switzerland)
We have studied the effects of various conditions of rapid thermal annealing (RTA) on 10 nm GaInNAs/GaAs single quantum wells (SQWs) with fixed indium concentration and increasing nitrogen content to obtain photoluminescence (PL) in the telecom wavelength regime of 1.3 and 1.5 {mu}m. Specifically, we analyzed the results of annealing for a fixed short time but at different temperatures and for longer times at a fixed temperature. In all experiments, InGaAs SQWs with the same In concentration were used as references. For both RTA conditions, the well-known blueshift of the band gap energy and the PL intensity improvement show trends that reveal that these are unrelated effects. At high RTA temperatures the PL efficiency reaches a maximum and then drops independently of N content. On the contrary, the blueshift experiences a rapid increase up to 700 deg. C (strong blueshift regime) and it saturates above this temperature (weak blueshift regime). Both these blueshift regimes are related to the nitrogen content in the SQWs but in different ways. In the strong blueshift regime, we could obtain activation energy for the blueshift process in the range of 1.25 eV, which increases with N content. Analysis with high-resolution x-ray diffraction (HRXRD) shows that the blueshift experienced in this regime is not due to a stoichiometric change in the QW. In the weak blueshift regime, the blueshift, which is only partly due to In outdiffusion, saturates more slowly the higher the N content. Annealing at the same temperature (600 deg. C) for a longer time shows that the blueshift saturates earlier than the PL intensity and that samples with higher nitrogen experience a larger blueshift. Only a small In outdiffusion for annealing at high temperatures (>650 deg. C) and long duration was observed. However, this modest stoichiometric change does not explain the large blueshift experienced by the GaInNAs SQWs. We conclude that the mechanism responsible for the drastic blueshift after annealing is related to the N content in the QW, while the improvement in PL integrated intensity is uniquely related to the annealing conditions.
Monolithic integration of Ga(NAsP)/(BGa)P multi-quantum well structures on (0 0 1) silicon substrate by MOVPE
NASA Astrophysics Data System (ADS)
Kunert, B.; Zinnkann, S.; Volz, K.; Stolz, W.
The pseudomorphic integration of an active III/V laser material onto Si substrates requires precise strain management of the entire several-?m-thick structure at both room and growth temperature. The incorporation of B into (BGa)P allows for the deposition of tensilely strained layers on the Si substrate in order to strain compensate the highly compressively strained Ga(NAsP) active material system. It is shown that the incorporation efficiency of B under the chosen conditions is unity and that (BGa)P layers with B concentrations high enough to allow for the strain compensation of an active Ga(NAsP) laser material on Si can be grown with excellent structural quality. Therefore, Ga(NAsP)/(BGa)P multi-quantum well heterostructures (MQWHs) with high-crystal quality as determined by high-resolution X-ray diffraction (XRD) were pseudomorphically grown on (0 0 1) Si substrates. The potential of this material combination to serve as an active optoelectronic device on Si is demonstrated by efficient room-temperature photoluminescence observed from the integrated Ga(NAsP) MQWH.
Proceedings of Institute of Mathematics of NAS of Ukraine 2000, Vol. 30, Part 1, 127130. Oscillation of Solutions of Ordinary Differential
Popovych, Roman
Proceedings of Institute of Mathematics of NAS of Ukraine 2000, Vol. 30, Part 1, 127 Algebra Lyudmyla V. KHOMCHENKO Institute of Mathematics of the National Academy of Sciences of Ukraine, 3 Tereshchenkivs'ka Str., Kyiv, Ukraine The class of nonlinear second order systems having oscillation solutions
Proceedings of Institute of Mathematics of NAS of Ukraine 2004, Vol. 50, Part 3, 11011107 Classical Dynamical YangBaxter Equations
Popovych, Roman
Proceedings of Institute of Mathematics of NAS of Ukraine 2004, Vol. 50, Part 3, 1101, Ukraine; Institute for Low Temperature Physics & Engineering, 47 Lenin Ave., 61103 Kharkiv, Ukraine E Kharkiv, Ukraine § Department of Mathematics, University of G¨oteborg, SE-412 96 G¨oteborg, Sweden E
Proceedings of Institute of Mathematics of NAS of Ukraine 2004, Vol. 50, Part 2, 939946 Charge Fractionalization in a Planar System with
Popovych, Roman
Proceedings of Institute of Mathematics of NAS of Ukraine 2004, Vol. 50, Part 2, 939Â946 Charge, Ukraine E-mail: email@example.com Department of Physics, Taras Shevchenko National University of Kyiv, 6 Academician Glushkov Ave., 03680 Kyiv, Ukraine E-mail: firstname.lastname@example.com States
Proceedings of Institute of Mathematics of NAS of Ukraine 2004, Vol. 50, Part 3, 14101414 Symmetry Analysis in Spikes (Bursts) Recognition
Popovych, Roman
Proceedings of Institute of Mathematics of NAS of Ukraine 2004, Vol. 50, Part 3, 1410Â1414 Symmetry and Igor TETKO Institute of Applied System Analysis, National Technical University of Ukraine (KPI), 37 Peremogy Ave., Kyiv, Ukraine E-mail: email@example.com, email@example.com Institute
Proceedings of Institute of Mathematics of NAS of Ukraine 2000, Vol. 30, Part 2, 357363. On Generalization of the Cuntz Algebras
Popovych, Roman
Proceedings of Institute of Mathematics of NAS of Ukraine 2000, Vol. 30, Part 2, 357 Analysis, Institute of Mathematics of the National Academy of Sciences of Ukraine, 3 Tereshchenkivs'ka Str., Kyiv, Ukraine E-mail: firstname.lastname@example.com Institute of Economics, Management and Business Laws, 30
Proceedings of Institute of Mathematics of NAS of Ukraine 2000, Vol. 30, Part 1, 177179. A Class of Non-Lie Solutions
Popovych, Roman
Proceedings of Institute of Mathematics of NAS of Ukraine 2000, Vol. 30, Part 1, 177Â179. A Class of Ukraine, 3 Tereshchenkivska Street, Kyiv, Ukraine E-mail: email@example.com New class of exact of Sciences of Ukraine, 1998, V.19, 166Â173. [2] Fushchych W.I., Zhdanov R.Z. and Reven
Submitted Eighth USA/Europe Air Traffic Management Research and Development Seminar (ATM2009) Trading-off Multi-Dimensional NAS Performance
) Trading-off Multi-Dimensional NAS Performance and Equity Metrics Using Data Envelopment Analysis David. Data Envelopment Analysis (DEA) overcomes these limitations and provides an assessment of the overall are discussed. Keywords- Data Envelopment Analysis; Equity; Rationing rules I. INTRODUCTION The growth in demand
"Na orgem da ideia de fronteiras mveis: limites polticos e migraes nas geografias de Friedrich Ratzel e Elise Reclus", Continentes, Revista de Geografia UFRRJ, n. 4, 2014
Boyer, Edmond
.br/revistaconti/index.php/continentes/article/view/38 [Texte] [Texte] AS ORIGENS DA NOÇÃO DE "FRONTEIRAS MÓVEIS" Limites Políticos e Migrações nas of the idea of "mobile borders" : political limits and migrations in Friedrich Ratzel's and Élisée Reclus in the historical process. Keywords: Élisée Reclus; Friedrich Ratzel; borders; politics; History of Geographical
Multiple stacking of self-assembled InAs quantum dots embedded by GaNAs strain compensating layers
Oshima, Ryuji; Hashimoto, Takayuki; Shigekawa, Hidemi; Okada, Yoshitaka [Institute of Applied Physics, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8573 (Japan)
We have investigated a growth technique to realize high-quality multiple stacking of self-assembled InAs quantum dots (QDs) on GaAs (001) substrates, in which GaN{sub x}As{sub 1-x} dilute nitride material was used as a strain compensation layer (SCL). The growth was achieved by atomic hydrogen-assisted rf molecular beam epitaxy, and the effect of strain compensation was systematically investigated by using high-resolution x-ray diffraction measurements. By controlling the net average lattice strain to a minimum by covering each QD layer with a 40-nm-thick GaN{sub 0.005}As{sub 0.995} SCL, we obtained a superior QD structure with no degradation in size homogeneity. Further, no dislocations were generated even after 30 layers of stacking, and the area density of QDs amounted to as high as 3x10{sup 12} cm{sup -2}. The photoluminescence peak linewidth was improved by about 22% for QDs embedded in GaNAs SCLs as the accumulation of lattice strain with increasing growth of QD layers was avoided, which would otherwise commonly lead to degradation of size homogeneity and generation of dislocations.
The solution of linear systems of equations with a structural analysis code on the NAS CRAY-2
NASA Technical Reports Server (NTRS)
Poole, Eugene L.; Overman, Andrea L.
Two methods for solving linear systems of equations on the NAS Cray-2 are described. One is a direct method; the other is an iterative method. Both methods exploit the architecture of the Cray-2, particularly the vectorization, and are aimed at structural analysis applications. To demonstrate and evaluate the methods, they were installed in a finite element structural analysis code denoted the Computational Structural Mechanics (CSM) Testbed. A description of the techniques used to integrate the two solvers into the Testbed is given. Storage schemes, memory requirements, operation counts, and reformatting procedures are discussed. Finally, results from the new methods are compared with results from the initial Testbed sparse Choleski equation solver for three structural analysis problems. The new direct solvers described achieve the highest computational rates of the methods compared. The new iterative methods are not able to achieve as high computation rates as the vectorized direct solvers but are best for well conditioned problems which require fewer iterations to converge to the solution.
GaInNAs-based Hellish-vertical cavity semiconductor optical amplifier for 1.3 ?m operation.
Chaqmaqchee, Faten Adel Ismail; Mazzucato, Simone; Oduncuoglu, Murat; Balkan, Naci; Sun, Yun; Gunes, Mustafa; Hugues, Maxime; Hopkinson, Mark
Hot electron light emission and lasing in semiconductor heterostructure (Hellish) devices are surface emitters the operation of which is based on the longitudinal injection of electrons and holes in the active region. These devices can be designed to be used as vertical cavity surface emitting laser or, as in this study, as a vertical cavity semiconductor optical amplifier (VCSOA). This study investigates the prospects for a Hellish VCSOA based on GaInNAs/GaAs material for operation in the 1.3-?m wavelength range. Hellish VCSOAs have increased functionality, and use undoped distributed Bragg reflectors; and this coupled with direct injection into the active region is expected to yield improvements in the gain and bandwidth. The design of the Hellish VCSOA is based on the transfer matrix method and the optical field distribution within the structure, where the determination of the position of quantum wells is crucial. A full assessment of Hellish VCSOAs has been performed in a device with eleven layers of Ga0.35In0.65N0.02As0.08/GaAs quantum wells (QWs) in the active region. It was characterised through I-V, L-V and by spectral photoluminescence, electroluminescence and electro-photoluminescence as a function of temperature and applied bias. Cavity resonance and gain peak curves have been calculated at different temperatures. Good agreement between experimental and theoretical results has been obtained. PMID:21711630
D. Bailey; E. Barszcz; J. Barton; D. Browning; R. Carter; L. Dagum
A new set of benchmarks has been developed for the performance evaluation of highly parallel supercomputers. These benchmarks consist of five parallel kernels and three simulated application benchmarks. Together theymimic the computation and data movement characteristics of large scale computational fluid dynamics (CFD) applications.The principal distinguishing feature of these benchmarks is their penciland paper specification---all details of these benchmarks are
Intrinsic temperature sensitivities of 1.3 ?m GaInNAs\\/GaAs, InGaAsP\\/InP and AlGaInAs\\/InP-based semiconductor lasers
S. J. Sweeney; R. Fehse; A. R. Adams; H. Riechert
The apparent temperature stability of GaInNAs-based lasers is attributed to significant defect current. By removing this current, GaInNAs devices have a similar temperature dependence to InGaAsP devices whilst AlGaInAs devices are more thermally stable.
Molecular beam epitaxy of GaNAs alloys with high As content for potential photoanode applications in hydrogen production
Novikov, S. V.; Staddon, C. R.; Foxon, C. T.; Yu, K. M.; Broesler, R.; Hawkridge, M.; Liliental-Weber, Z.; Walukiewicz, W.; Denlinger, J.; Demchenko, I.
The authors have succeeded in growing GaN1?xAsx alloys over a large composition range (0 < x < 0.8) by plasma-assisted molecular beam epitaxy. The enhanced incorporation of As was achieved by growing the films with high As{sub 2} flux at low (as low as 100 C) growth temperatures, which is much below the normal GaN growth temperature range. Using x-ray and transmission electron microscopy, they found that the GaNAs alloys with high As content x > 0.17 are amorphous. Optical absorption measurements together with x-ray absorption and emission spectroscopy results reveal a continuous gradual decrease in band gap from -3.4 to < 1 eV with increasing As content. The energy gap reaches its minimum of -0.8 eV at x - 0.8. The composition dependence of the band gap of the crystalline GaN{sub 1?x}As{sub x} alloys follows the prediction of the band anticrossing model (BAC). However, our measured band gap of amorphous GaN{sub 1?x}As{sub x} with 0.3 < x < 0.8 are larger than that predicted by BAC. The results seem to indicate that for this composition range the amorphous GaN{sub 1?x}As{sub x} alloys have short-range ordering that resembles random crystalline GaN{sub 1?x}As{sub x} alloys. They have demonstrated the possibility of the growth of amorphous GaN{sub 1?x}As{sub x} layers with variable As content on glass substrates
Morphological instability of GaInNAs quantum wells on Al-containing layers grown by metalorganic vapor-phase epitaxy
NASA Astrophysics Data System (ADS)
Sundgren, P.; Asplund, C.; Baskar, K.; Hammar, M.
We report on the optical and structural integrity of metalorganic vapor-phase epitaxy-grown GaInNAs/GaAs single quantum wells on AlGaAs/GaAs distributed Bragg reflectors (DBRs). Photoluminescence and surface morphology as measured by atomic force microscopy were investigated for different numbers of DBR periods and different DBR-growth temperatures. An increasing number of DBR periods may severely degrade the quantum well surface morphology and photoluminescence. Surface secondary-ion mass spectroscopy revealed surface segregation of an Al-containing species. Decreasing the DBR-growth temperature lowers the surface concentration of Al and improves the GaInNAs quantum-well morphology.
Weather Requirements and Procedures for Step 1: High Altitude Long Endurance (HALE) Unmanned Aircraft System (UAS) Flight Operations in the National Air Space (NAS)
NASA Technical Reports Server (NTRS)
This cover sheet is for version 2 of the weather requirements document along with Appendix A. The purpose of the requirements document was to identify and to list the weather functional requirements needed to achieve the Access 5 vision of "operating High Altitude, Long Endurance (HALE) Unmanned Aircraft Systems (UAS) routinely, safely, and reliably in the National Airspace System (NAS) for Step 1." A discussion of the Federal Aviation Administration (FAA) references and related policies, procedures, and standards is provided as basis for the recommendations supported within this document. Additional procedures and reference documentation related to weather functional requirements is also provided for background. The functional requirements and related information are to be proposed to the FAA and various standards organizations for consideration and approval. The appendix was designed to show that sources of flight weather information are readily available to UAS pilots conducting missions in the NAS. All weather information for this presentation was obtained from the public internet.
GaInNAs Structures Grown by MBE for High-Efficiency Solar Cells: Final Report; 25 June 1999--24 August 2002
Tu, C. W.
The focus of this work is to improve the quality of GaInNAs by advanced thin-film growth techniques, such as digital-alloy growth techniques and migration-enhanced epitaxy (MEE). The other focus is to further investigate the properties of such materials, which are potentially beneficial for high-efficiency, multijunction solar cells. 400-nm-thick strain-compensated Ga0.92In0.08As/GaN0.03As0.97 short-period superlattices (SPSLs) are grown lattice-matched to GaAs substrates. The photoluminescence (PL) intensity of digital alloys is 3 times higher than that of random alloys at room temperature, and the improvement is even greater at low temperature, by a factor of about 12. The room-temperature PL intensity of the GaInNAs quantum well grown by the strained InAs/GaN0.023As SPSL growth mode is higher by a factor 5 as compare to the continuous growth mode. The SPSL growth method allows for independent adjustment of the In-to-Ga ratio without group III competition. MEE reduces the low-energy tail of PL, and PL peaks become more intense and sharper. The twin peaks photoluminescence of GaNAs grown on GaAs was observed at room temperature. The peaks splitting increase with increase in nitrogen alloy content. The strain-induced splitting of light-hole and heavy-hole bands of tensile-strained GaNAs is proposed as an explanation of such behavior.
Unmanned Aircraft Systems (UAS) Integration in the National Airspace System (NAS) Project, UAS Control and Non-Payload Communication System Phase-1 Flight Test Results
NASA Technical Reports Server (NTRS)
Griner, James H.
NASA's UAS Integration in the NAS project, has partnered with Rockwell Collins to develop a concept Control and Non-Payload Communication (CNPC) system prototype radio, operating on recently allocated UAS frequency spectrum bands. This prototype radio is being used to validate initial proposed performance requirements for UAS control communications. This presentation will give an overview of the current status of the prototype radio development, and results from phase 1 flight tests conducted during 2013.
Diffusion mechanisms of indium and nitrogen during the annealing of InGaAs quantum wells with GaNAs barriers and GaAs spacer layers
NASA Astrophysics Data System (ADS)
Oye, Michael M.; Govindaraju, Sridhar; Sidhu, Rubin; Reifsnider, Jason M.; Holmes, Archie L.
In this article, we discuss two indium diffusion mechanisms that are present during the rapid thermal annealing of InxGa1-xAs quantum wells (x =0.18, 0.22, and 0.26) with GaNyAs1-y barriers (y =0.6 or 1.2%). Samples were grown with and without a GaAs spacer layer in between the quantum well and barrier. The dominant mechanism is dependent on the amount of thermal energy applied during the annealing process. At low annealing times and temperatures, we have observed that In-Ga intra-diffusion entirely within the quantum well is dominant. For the higher times and temperatures, In-Ga inter-diffusion between the quantum well and barrier becomes dominant. These observations were confirmed by high-resolution x-ray diffraction and the peak emission wavelengths were measured by room-temperature photoluminescence. We have also observed that nitrogen had diffused from the GaNAs barriers into the InGaAs quantum wells in all of our annealed samples. In addition, the commonly observed indium-content dependent diffusion in GaInNAs-based systems was not observed with InGaAs /GaNAs-based structures.
Correlation between hetero-interface properties and photoluminescence efficiency of Ga(NAsP)/(BGa)P multi-quantum well structures on (0 0 1) Si substrate
NASA Astrophysics Data System (ADS)
Kunert, Bernardette; Liebich, Sven; Beyer, Andreas; Fritz, Rafael; Zinnkann, Steffen; Volz, Kerstin; Stolz, Wolfgang
The photoluminescence (PL) characteristic of Ga(NAsP)/(BGa)P quantum well heterostructures pseudomorphically grown on (0 0 1) Si substrates are dominated by the compound semiconductor crystal quality in line with local defects and impurities, but also influenced by the hetero-interface morphology. A comparison of the PL line width of multi-quantum well (QW) structures with different QW thicknesses reveals an increase in line width due to interfacial composition undulation. The degree of interface roughness is related to the N concentration of the active material system. A pronounced decline in PL intensity of the QW material is observed when B and N precursors are simultaneous utilized in the metal organic vapor phase epitaxy growth process. In order to preserve the luminescence efficiency a GaP spacer layer is inserted between each B-containing barrier film and the Ga(NAsP) active material system. The minimum required GaP film thickness is linked to the amount of interface undulation. A GaP spacer width of 3 nm is sufficient to maintain the luminescence intensity of Ga(NAsP)/(BGa)P multi-quantum well heterostructures.
Identification of nitrogen- and host-related deep-level traps in n-type GaNAs and their evolution upon annealing
Gelczuk, ?., E-mail: email@example.com [Faculty of Microsystem Electronics and Photonics, Wroclaw University of Technology, Janiszewskiego 11/17, 50-372 Wroclaw (Poland); Kudrawiec, R., E-mail: firstname.lastname@example.com [Institute of Physics, Wroclaw University of Technology, Wybrzeze Wyspianskiego 27, 50-370 Wroclaw (Poland); Henini, M. [School of Physics and Astronomy, University of Nottingham, Nottingham NG7 2RD (United Kingdom)
Deep level traps in as-grown and annealed n-GaNAs layers (doped with Si) of various nitrogen concentrations (N=0.2%, 0.4%, 0.8%, and 1.2%) were investigated by deep level transient spectroscopy. In addition, optical properties of GaNAs layers were studied by photoluminescence and contactless electroreflectance. The identification of N- and host-related traps has been performed on the basis of band gap diagram [Kudrawiec, Appl. Phys. Lett. 101, 082109 (2012)], which assumes that the activation energy of electron traps of the same microscopic nature decreases with the rise of nitrogen concentration in accordance with the N-related shift of the conduction band towards trap levels. The application of this diagram has allowed to investigate the evolution of donor traps in GaNAs upon annealing. In general, it was observed that the concentration of N- and host-related traps decreases after annealing and PL improves very significantly. However, it was also observed that some traps are generated due to annealing. It explains why the annealing conditions have to be carefully optimized for this material system.
Room-temperature continuous-wave operation of 1.24-?m GaInNAs lasers grown by metal-organic chemical vapor deposition
Shunichi Sato; Shiro Satoh
Room-temperature continuous-wave operation is demonstrated for the first time in a GaInNAs-GaAs laser grown by metal-organic chemical vapor deposition. A low-threshold current density of 660 A\\/cm2 and a high characteristic temperature of 113 K emitting at 1.245 ?m is achieved. Emitting at the longest wavelength of 1.225 ?m is also demonstrated in a highly strained GaInAs-GaAs double-quantum-well laser on a
A model for the bandgap energy of the dilute nitride InGaNAs alloys by modifying simplified coherent potential approximation
NASA Astrophysics Data System (ADS)
Zhao, Chuan-Zhen; Qu, You-Yang; Wei, Tong; Sun, Xiao-Dong; Wang, Sha-Sha; Lu, Ke-Qing
In this paper, a model describing the bandgap energy of the dilute nitride alloy InxGa1-xNyAs1-y is developed based on the modification of simplified coherent potential approximation (MSCPA) and the band anti-crossing model (BAC). The parameters in the model are obtained by fitting the experimental bandgap energies of the ternary alloys InGaAs, InGaN, GaNAs and InNAs. It is found that the results agree well with the experimental data. We also find that although the bandgap energies of InxGa1-xNyAs1-y and InxGa1-xAs can be calculated by using MSCPA, the physical mechanisms for the bandgap evolution of InxGa1-xNyAs1-y and InxGa1-xAs are very different. In addition, it is found that the model in this work may be used in a larger composition range than the BAC model.
Instituto Nacional de Pesquisas Espaciais Exame para o curso de ps-graduao em Astrofsica
for Extraterrestrial Intelligence), afirmava que o grande radiotelescópio de Arecibo, em Porto Rico, "pode detectar um magnético? b) A que aceleração ele é submetido? #12;6. Frank Drake, um dos criadores do projeto SETI (Search
INSTITUTO NACIONAL DE PESQUISAS ESPACIAIS Edital n 6 de 10 de Setembro de 2012
PROVAS: - Auditório do CCST - INPE/Cachoeira Paulista/SP Nome do Candidato Data Horário DANIEL ALEJANDRO GONÇALVES 18/9/2012 15:00hs SIMONE MARILENE SIEVERT DA COSTA COELHO 19/9/2012 8:00hs CAIO AUGUSTO DOS SANTOS CCST - INPE/Cachoeira Paulista/SP Nome do Candidato Data Horário DANIEL ANDRES RODRIGUEZ 20/9/2012 9:
,00 10,70 JORGE ANTONIO FURTADO LIMA 0004 60,00 18,93 JOSÉ PINHEIRO DE MOURA JÚNIOR 0989 46,00 12 Geral CÓDIGO DE GARGO TM01 ANICETO JOZIEL RABELO GOMES ANDRADE 0790 60,00 18,64 ANTONIO CARLOS LIMA,00 4,64 CÓDIGO DE CARGO TM02 ANTONIO FEITOSA CASTELO BRANCO 0550 36,00 14,84 DIEGO FERREIRA DE SOUZA
específicas ao Conselho de Área de Concentração: #12;2 I um membro, presidente, com direito a voto; que deverá impedimentos temporários) com direito a voto. O coordenador do Conselho de Área de Concentração deverá nomear Corpo Discente, com direito a voto; Art. 5 Os integrantes do Conselho de Área de Concentração cumprirão
, com direito a voto; que deverá ser o representante e Coordenador Acadêmico da Área de Concentração e o presidente em seus impedimentos temporários) com direito a voto. O coordenador do Conselho de Área temporários. III um representante do Corpo Discente, com direito a voto; Art. 5 Os integrantes do Conselho
membro, presidente, Coordenador Acadêmico do Curso, com direito a voto; II três membros, representantes do Corpo Docente (e que poderão substituir o presidente em seus impedimentos temporários) com direito representante do Corpo Discente, com direito a voto; Art. 5o Os integrantes do Conselho de Curso cumprirão
específicas ao Conselho de Área de Concentração: I um membro, presidente, com direito a voto; que deverá ser impedimentos temporários) com direito a voto. O coordenador do Conselho de Área de Concentração deverá nomear Corpo Discente, com direito a voto; Art. 5º Os integrantes do Conselho de Área de Concentração
, com direito a voto; que deverá ser o representante e Coordenador Acadêmico da Área de Concentração e substituir o presidente em seus impedimentos temporários) com direito a voto. O coordenador do Conselho de temporários. III um representante do Corpo Discente, com direito a voto; Art. 5 Os integrantes do Conselho
funções específicas ao Conselho de Área de Concentração: #12;2 I um membro, presidente, com direito presidente em seus impedimentos temporários) com direito a voto. O coordenador do Conselho de Área de representante do Corpo Discente, com direito a voto; Art. 5º. Os integrantes do Conselho de Área de
direito a voto; que deverá ser o representante e Coordenador Acadêmico da Área de Concentração e membro do presidente em seus impedimentos temporários) com direito a voto. O coordenador do Conselho de Área de;2 III um representante do Corpo Discente, com direito a voto; Art. 5o Os integrantes do Conselho de
Pratt and Whitney/Boeing Engine Validation of Noise Reduction Concepts: Final Report for NASA Contract NAS3-97144, Phase 1
NASA Technical Reports Server (NTRS)
Mathews, Douglas; Bock, Larry A.; Bielak, Gerald W.; Dougherty, R. P.; Premo, John W.; Scharpf, Dan F.; Yu, Jia
Major airports in the world's air transportation systems face a serious problem in providing greater capacity to meet the ever increasing demands of air travel. This problem could be relieved if airports are allowed to increase their operating time, now restricted by curfews and by relaxing present limits on takeoffs and landings. The key operational issue in extending the present curfews is noise. In response to these increasing restrictive noise regulations, NASA has launched a program to validate through engine testing, noise reduction concepts and technologies that have evolved from the Advanced Subsonic Technologies (AST) Noise Reduction Program. The goal of this AST program was to develop and validate technology that reduces engine noise and improves nacelle suppression effectiveness relative to 1992 technology. Contract NAS3-97144 titled "Engine Validation of Noise Reduction Concepts" (EVNRC) was awarded to P&W on August 12, 1997 to conduct full scale noise reduction tests in two Phases on a PW4098 engine. The following Section 1.2 provides a brief description of the overall program. The remainder of this report provides a detailed documentation of Phase I of the program.
Map of a UAV flight operation in the NAS at the JER. The initial external pilot (EP) position is at P0. The UAV is launched at the red cross position into the
Map of a UAV flight operation in the NAS at the JER. The initial external pilot (EP) position is at P0. The UAV is launched at the red cross position into the launch orbit, and is then moved to the H1 holding orbit. Once the EP has moved from P0 to P1, the UAV acquires imagery over the first flight area
Cancer risk assessment foundation unraveling: new historical evidence reveals that the US National Academy of Sciences (US NAS), Biological Effects of Atomic Radiation (BEAR) Committee Genetics Panel falsified the research record to promote acceptance of the LNT.
Calabrese, Edward J
The NAS Genetics Panel (1956) recommended a switch from a threshold to a linear dose response for radiation risk assessment. To support this recommendation, geneticists on the panel provided individual estimates of the number of children in subsequent generations (one to ten) that would be adversely affected due to transgenerational reproductive cell mutations. It was hoped that there would be close agreement among the individual risk estimates. However, extremely large ranges of variability and uncertainty characterized the wildly divergent expert estimates. The panel members believed that sharing these estimates with the scientific community and general public would strongly undercut their linearity recommendation, as it would have only highlighted their own substantial uncertainties. Essentially, their technical report in the journal Science omitted and misrepresented key adverse reproductive findings in an effort to ensure support for their linearity recommendation. These omissions and misrepresentations not only belie the notion of an impartial and independent appraisal by the NAS Panel, but also amount to falsification and fabrication of the research record at the highest possible level, leading ultimately to the adoption of LNT by governments worldwide. Based on previously unexamined correspondence among panel members and Genetics Panel meeting transcripts, this paper provides the first documentation of these historical developments. PMID:25600588
Electric Machines with Non-Radially Mounted Rectangular Permanent Magnets / Elektrisk?s Maš?nas Ar Prizmatiskiem Neradi?li Novietotiem Past?v?gajiem Magn?tiem
NASA Astrophysics Data System (ADS)
Levin, N.; Pugachev, V.; Dirba, J.; Lavrinovicha, L.
The authors analyze the advantages and disadvantages of brushless synchronous electric machines with radially and non-radially mounted rectangular permanent magnets. The results show that the proposed nonradial mounting of permanent magnets considered in the paper, in several cases (e.g. multi-pole brushless generators with tooth windings of the armature) allows achievement of the following advantages: better technology of manufacturing the electric machine owing to simple packing of the stator winding in the stator open slots, which also increases the copper slot fillfactor; reduction in the mass-and-size of permanent magnets at least twice; significantly lower cost of the electric machine; and, finally, its greater specific power. Darb? tiek analiz?tas priekšroc?bas un tr?kumi sinhron?m bezkontaktu maš?n?m ar radi?li un neradi?li novietotiem prizmatiskiem past?v?gajiem magn?tiem. Par?d?ts, ka vair?kos gad?jumos, piem?ram, daudzpolu bezkontaktu sinhronajos ?eneratoros ar zobu tinumiem, neradi?ls past?v?go magn?tu izvietojums nodrošina vair?kas priekšroc?bas: uzlabojas maš?nas izgatavošanas tehnolo?ija, jo statora atv?rtaj?s riev?s viegl?k novietot tinumus un iesp?jams sasniegt augst?ku rievas aizpild?juma koeficientu; samazin?s past?v?go magn?tu masa un izmaksas; palielin?s maš?nas ?patn?ja jauda.
CAIO AUGUSTO DOS SANTOS COELHO 96,80 98,20 SJ032 DANIEL ALEJANDRO VILA 60,60 94,20 CP006 GUSTAVO CARLOS JUAN ESCOBAR 35,70 90,60 CP007 LUIZ GUSTAVO GONÇALVES DE GONÇALVES 76,85 90,00 CP008 SIMONE MARILENE Análise de Títulos e Currículo Prova Oral CP005 DANIEL ANDRES RODRIGUEZ 51,00 87,60 SJ095 LUDMILSON
ANTONIO FURTADO LIMA 0004 60,00 18,93 EDILBERTO DOS ANJOS TEIXEIRA 0052 34,00 10,89 ANTONIO CARLOS LIMA ANDRADE 0790 60,00 18,64 JOSÉ PINHEIRO DE MOURA JÚNIOR 0989 46,00 12,31 ILANA FRANÇA DOS SANTOS 1298 32: 14h30 DIEGO FERREIRA DE SOUZA 0171 44,00 18,97 ANTONIO FEITOSA CASTELO BRANCO 0550 36,00 14
Aglomerados de galxias Estruturas em grande escala no
dos Santos, C.A.
delineado por galáxias (e pela radiação de fundo de micro- ondas!). Galáxias se distribuem de forma não-uniforme de anos atrás. Tempo passado = - 4.5Ganos #12;O Grupo Local #12;Grupo Local animação #12;Outros entre galáxias Efeitos ambientais sobre formação de galáxias: relação morfologia-densidade, galáxias cD
High-gain 1.3???m GaInNAs semiconductor optical amplifier with enhanced temperature stability for all-optical signal processing at 10??Gb/s.
Fitsios, D; Giannoulis, G; Korpijärvi, V-M; Viheriälä, J; Laakso, A; Iliadis, N; Dris, S; Spyropoulou, M; Avramopoulos, H; Kanellos, G T; Pleros, N; Guina, M
We report on the complete experimental evaluation of a GaInNAs/GaAs (dilute nitride) semiconductor optical amplifier that operates at 1.3 ?m and exhibits 28 dB gain and a gain recovery time of 100 ps. Successful wavelength conversion operation is demonstrated using pseudorandom bit sequence 27-1 non-return-to-zero bit streams at 5 and 10??Gb/s, yielding error-free performance and showing feasibility for implementation in various signal processing functionalities. The operational credentials of the device are analyzed in various operational regimes, while its nonlinear performance is examined in terms of four-wave mixing. Moreover, characterization results reveal enhanced temperature stability with almost no gain variation around the 1320 nm region for a temperature range from 20°C to 50°C. The operational characteristics of the device, along with the cost and energy benefits of dilute nitride technology, make it very attractive for application in optical access networks and dense photonic integrated circuits. PMID:25967005
Response to Questions on Presentation to NAS
Meier, W R
Response to questions on the presentation 'Overview to Chamber and Power Plant Designs for IFE' made at the 1/29-31 meeting of the National Academies Committee on the Prospects for Inertial Confinement Fusion Energy Systems.
Rathbun, Julie A.
to confirm this theory two studies were conducted, !_ F" a theoretical one by the Bendix Corporation which be caused by the Incidence slowly mov- Ing highly charged particles. !? This theory was confirmed established, it Work Performed The program FREQ was modified to separate high and low PNA distributions
Multiband GaNAsP Quaternary Alloys
Yu, K.M.; Walukiewicz, W.; Ager III, J.W.; Bour, D.; Farshchi,R.; Dubon, O.D.; Li, S.X.; Sharp, I.D.; Haller, E.E.
We have synthesized GaN{sub x}As{sub 1-y}P{sub y} alloys (x {approx} 0.3-1% and y = 0-0.4) using nitrogen N ion implantation into GaAsP epilayers followed by pulsed laser melting and rapid thermal annealing techniques. As predicted by the band anticrossing model, the incorporation of N splits the conduction band (E{sub M}) of the GaAs{sub 1-y}P{sub y} substrate, and strong optical transitions from the valence band to the lower (E{sub -}) and upper (E{sub +}) conduction subbands are observed. The relative strengths of the E{sub -} and E{sub +} transition change as the localized N level E{sub N} emerges from the conduction band forming narrow intermediate band for y > 0.3. The results show that GaN{sub x}As{sub 1-x-y}P{sub y} alloys with y > 0.3 is a three band semiconductor alloy with potential applications for high-efficiency intermediate band solar cells.
Strategic Plans for the Future of Solar Physics: a community discussion of the NASA Sun-Earth Connection Program Roadmap and the NAS Decadal Survey of Astronomy and Astrophysics (Solar Astronomy section)
NASA Astrophysics Data System (ADS)
Schrijver, K.; Knoelker, M.
The NASA Sun-Earth Connections Program is currently revising its Roadmap, the long-range plan for science goals, technology development, and missions between 2000 and 2040. From the interior dynamics of the Sun, to the interactions of plasma, fields, and radiation in the photosphere and solar atmosphere, to the heating and structure of the corona, to the acceleration, structure, and evolution of the solar wind, to the interactions of the heliosphere with the interstellar medium, to the processes of solar, stellar, and solar system evolution - progress in each of these domains will help us understand how the Sun impacts our home in space. The Roadmap Committee is seeking to refine and extend the SEC's vision and identify the milestone missions for the future. During this session, an outline of the current draft Roadmap will be presented, and further community involvement will be solicited to ensure the strongest possible concensus on the revised Roadmap. The National Academy of Sciences' Space Science Board has appointed a committee to perform a Decadal Survey of Astronomy and Astrophysics, which is surveying the field of space- and ground-based astronomy and astrophysics, recommending priorities for the most important new initiatives of the decade 2000-2010. The prioritization delivered by the earlier Decadal Surveys has played an important role in guiding the funding agencies in setting their priorities for astronomy and astrophysics. Therefore it will be of crucial importance for solar physics to contribute a strong case for its own set of future projects to be incorpoprated into the survey. The solar physics of the next decade will be characterized by its increasing societal relevance in the context of the National Space Weather Program and related issues, as well as its classical importance as a ``base" for many astrophysical questions. The presentation and subsequent discussion at the Chicago meeting is intended to solicit further community input, to achieve optimal representation for solar physics in the Decadal Survey. The Roadmap Committee and the Decadal Survey's solar panel encourage the whole solar physics community to contact them prior to the meeting. The list of the committee/panel members and their e-mail addresses, as well as related information, can be accessed via their websites at http://www.lmsal.com/sec/ and http://www.nas.edu/bpa/projects/astrosurvey/solar/ , respectively.
Comparison of methods for the calculation of thermal contact resistance of the first Brazilian satellite. M.S. Thesis - Instituto de Pesquisas Espaciais, 6 Dec. 1985
NASA Technical Reports Server (NTRS)
Mantelli, Marcia B. H.
A comparative study of the methods developed for the calculation of thermal contact resistance between two surfaces submitted to a perpendicular heat flux is presented. Several factors affecting this resistance are analyzed and a brief historical review of the works in this field is made, spotting the methods of interest for space applications. These are compared to experimental data so as to establish the most proper method for the couplings of the first Brazilian satellite.
Multicast Semi-confiável Eficiente para Aplicações Multimídia Distribuídas em Redes de Larga Escala
Christiane Montenegro Bortoleto; Lau Cheuk Lung; Frank A. Siqueira; Alysson Neves Bessani; Joni da Silva Fraga
This paper proposes a semi-reliable multicast protocol that aims to increase the quality of video streams transmitted in large-scale systems and the communications network. The proposed protocol relies on the neighboring receivers for retransmitting lost packets, resulting in much faster recovery, which is vital in order to receive retransmitted packets on time to be exhibited. Resumo. Este artigo apresenta a
Utilidad de la escala INTERMACS para estratificar el pronóstico tras el trasplante cardiaco urgente
Eduardo Barge-Caballero; María J. Paniagua-Martín; Raquel Marzoa-Rivas; Rosa Campo-Pérez; José Ángel Rodríguez-Fernández; Alberto Pérez-Pérez; Lourdes García-Bueno; Paula Blanco-Canosa; Zulaika Grille Cancela; Miguel Solla Buceta; Alberto Juffé-Stein; José M. Herrera-Noreña; José J. Cuenca-Castillo; Javier Muñiz; Alfonso Castro-Beiras; María G. Crespo-Leiro
Introduction and objectivesOur aim was to assess the prognostic value of the INTERMACS (Interagency Registry for Mechanically Assisted Circulatory Support) scale in patients undergoing urgent heart transplantation (HT).
ALSEP TECHNICAL SPECIFICATION Contract NAS 9-5829
Rathbun, Julie A.
Interface Requirements . 3.2.1 System Interface Requirements 3. 2. 1. 1 LEM Spacecraft/ ALSEP Interface 3. 2 Cable 3. 2. 2. 3. 3 Thermal Control 3.2. 2.3.4 Size and Form Factor 126.96.36.199.5 Weight 3.2. 2.3.6 Power 220.127.116.11.3 Interconnecting Cable 3. 2. 2.4.4 Thermal Control 3. 2. 2.4. 5 Size and Form Factor 3. 2. 2.4.6 Weight 3. 2. 2
NAS Associate Works on Environmental Implications of Nanoparticles
Dr. Manomita Patra joined the EPA's, Human Exposure and Atmospheric Sciences Division at the Las Vegas, NV location in June 2007. Her research project parallels her previous interests in the genotoxicity of mercury in plants. She is working with Dr. Kim Rogers and Tammy Jones-Lep...
Fotografia nas eleições: efeitos de segundo nível do agenda setting
Paulo Munhoz
The article attempts to test the hypothesis that saliency (first level of agenda-setting) and image atributes (second level of agenda-setting) also occur through photography. As empirical material for a case- study, one has collected and analised photojournalistic elements in the press coverage of municipal elections in Salvador (Bahia). The general conclusion is that media vehicles do set valorative agendas not
Heinz Erzberger
The next-generation air-traffic control system will have to be able to handle, safely and efficiently, a traffic density that will be two or three times that accommodated by the present system. Capacity of the en route and transition (arrival\\/departure) airspace of the present system is principally limited by the controller workload associated with monitoring and controlling aircraft separation. Therefore, the
Band Anticrossing in GaInNAs Alloys
W. Shan; W. Walukiewicz; J. W. Ager III; E. E. Haller; J. F. Geisz; D. J. Friedman; J. M. Olson; S. R. Kurtz
We present evidence for a strong interaction between the conduction band and a narrow resonant band formed by nitrogen states in Ga 1-xIn xN yAs 1-y alloys. The interaction leads to a splitting of the conduction band into two subbands and a reduction of the fundamental band gap. An anticrossing of the extended states of the conduction band of the
Comparison of leading parallel NAS file systems on commodity hardware
Hedges, R; Fitzgerald, K; Gary, M; Stearman, D M
High performance computing has experienced tremendous gains in system performance over the past 20 years. Unfortunately other system capabilities, such as file I/O, have not grown commensurately. In this activity, we present the results of our tests of two leading file systems (GPFS and Lustre) on the same physical hardware. This hardware is the standard commodity storage solution in use at LLNL and, while much smaller in size, is intended to enable us to learn about differences between the two systems in terms of performance, ease of use and resilience. This work represents the first hardware consistent study of the two leading file systems that the authors are aware of.
Job Management Requirements for NAS Parallel Systems and Clusters
NASA Technical Reports Server (NTRS)
Saphir, William; Tanner, Leigh Ann; Traversat, Bernard
A job management system is a critical component of a production supercomputing environment, permitting oversubscribed resources to be shared fairly and efficiently. Job management systems that were originally designed for traditional vector supercomputers are not appropriate for the distributed-memory parallel supercomputers that are becoming increasingly important in the high performance computing industry. Newer job management systems offer new functionality but do not solve fundamental problems. We address some of the main issues in resource allocation and job scheduling we have encountered on two parallel computers - a 160-node IBM SP2 and a cluster of 20 high performance workstations located at the Numerical Aerodynamic Simulation facility. We describe the requirements for resource allocation and job management that are necessary to provide a production supercomputing environment on these machines, prioritizing according to difficulty and importance, and advocating a return to fundamental issues.
UAS Integration in the NAS Project and Future Autonomy Research
NASA Technical Reports Server (NTRS)
Johnson, Charles W.
This presentation highlights NASA use of unmanned aircraft systems (UAS) and related technologies for civil purposes. This briefing will give more insight into the UAS projects progress and future goals.
NAS Albuquerque 3/20/11 National Academy of Science
Advantages over CHS G > 100 Projected Gain A Gain ~100 at a compression energy of 1MJ is ideal for IFE FI 200 300 400 500 600 Full divergence cone angle 40o Fluor depth Imagewidth CCD Laserr K fluor Bragg
Transforming the NAS: The Next Generation Air Traffic Control System
NASA Technical Reports Server (NTRS)
Erzberger, Heinz
The next-generation air traffic control system must be designed to safely and efficiently accommodate the large growth of traffic expected in the near future. It should be sufficiently scalable to contend with the factor of 2 or more increase in demand expected by the year 2020. Analysis has shown that the current method of controlling air traffic cannot be scaled up to provide such levels of capacity. Therefore, to achieve a large increase in capacity while also giving pilots increased freedom to optimize their flight trajectories requires a fundamental change in the way air traffic is controlled. The key to achieving a factor of 2 or more increase in airspace capacity is to automate separation monitoring and control and to use an air-ground data link to send trajectories and clearances directly between ground-based and airborne systems. In addition to increasing capacity and offering greater flexibility in the selection of trajectories, this approach also has the potential to increase safety by reducing controller and pilot errors that occur in routine monitoring and voice communication tasks.
Dilute nitride GaInNAs and GaInNAsSb solar cells by molecular beam epitaxy
David B. Jackrel; Seth R. Bank; Homan B. Yuen; Mark A. Wistey; James S. Harris; Aaron J. Ptak; Steven W. Johnston; Daniel J. Friedman; Sarah R. Kurtz
Dilute nitride films with a roughly 1 eV band gap can be lattice-matched to gallium arsenide and germanium, and therefore could become a critical component in next-generation multijunction solar cells. To date most dilute nitride solar cells have been plagued with poor efficiency, due in large part to short diffusion lengths. This study focuses on two techniques aimed at improving
Development of Educational Resources to Include the Teaching of Astronomy in the First Years of the Basic Education. (Spanish Title: Desarrollo de Recursos Pedagógicos Para Incluir la Enseñanza de la Astronomía en los Primeros Años de la Educación Básica.) Desenvolvimento de Recursos Pedagógicos Para Inserir o Ensino de Astronomia nas Séries Iniciais do Ensino Fundamental
NASA Astrophysics Data System (ADS)
da Silva Morett, Samara; de Oliveira Souza, Marcelo
In this report will be presented the development of educational resources for the presentation of concepts of astronomy in the early grades of elementary school. This material is composed by presentations developed with the use of new technological resources, by the development of experiments and by the presentation of curiosities related to this field. The experiments were constructed with low cost material in order to allow the students involved to rework them in other occasions. The material presented aims to emphasize the relationship between Astronomy and the daily life of students. The inclusion of Astronomy in elementary school is a way to demonstrate to students how this area is present in an active way in their daily lives. The classes involved in the project participated in a survey with the aim of providing information about the prior knowledge they had about topics in astronomy that were considered during the project. With the experiments conducted, and the aid of new technologies, the astronomical concepts were presented to students of 4th and 5th years of basic education of a municipal school of Campos dos Goytacazes (RJ). After the presentations new data collections were carried out with the aim of verifying the level of learning obtained and it was observed that the method used was an important tool to aid the process of teaching and learning. The project obtained good results. En este informe se presenta el desarrollo de recursos pedagógicos para la presentación de los conceptos de la astronomía en los primeros grados de la escuela primaria. Este material consiste en las presentaciones hechas con el uso de nuevos recursos tecnológicos, haciendo experimentos y análisis de objetos de interés relacionados con este ámbito. Los experimentos fueron construidos con material de bajo costo a fin de que los estudiantes involucrados podrían rehacer en otras ocasiones. El material presentado tiene como objetivo destacar la relación entre la astronomía y la vida cotidiana de los estudiantes. La inclusión de la astronomía en la escuela primaria es una manera de demostrar a los estudiantes cómo este campo está presente de forma activa en su vida cotidiana. Las clases que participan en el proyecto participaron en un estudio con el objetivo de proporcionar información a los conocimientos previos que tenían sobre los temas de la astronomía que se examinaron durante el proyecto. Con los experimentos realizados, y la ayuda de las nuevas tecnologías, conceptos astronómicos fueron presentados a los estudiantes de 4to y 5to año de la educación básica de una escuela municipal de Campos dos Goytacazes (RJ). Después de las presentaciones nuevos datos fueran colectados y se han llevado a cabo con el fin de verificar el nivel de aprendizaje alcanzado y se observó que el método utilizado fue una herramienta importante para ayudar al proceso de enseñanza y aprendizaje. El proyecto logró resultados satisfactorios. Neste trabalho será apresentado o desenvolvimento de recursos pedagógicos para a apresentação de conceitos de astronomia nas séries iniciais do ensino fundamental. Este material é composto por apresentações realizadas com o uso de novos recursos tecnológicos, pela fabricação de experimentos e a discussão de curiosidades relativas a esta área de conhecimento. Os experimentos foram construídos com material de baixo custo com o objetivo de permitir que os alunos envolvidos pudessem refazê-los em outras ocasiões. O material apresentado busca enfatizar a relação entre a astronomia e o cotidiano dos alunos. A inclusão da astronomia no ensino fundamental e uma forma de demonstrar aoestudante como esta área está presente de forma ativa em seu cotidiano. As turmas envolvidas no projeto participaram de uma pesquisa com o objetivo de obter dados relativos ao conhecimento prévio que possuíam sobre os tópicos de astronomia que foram considerados no decorrer do projeto. Com os experimentos desenvolvidos, o auxílio de novas tecnologias, foram apresentados conceitos astronômicos aos aluno
Validação de escala de determinação funcional da qualidade de vida na esclerose múltipla para a língua portuguesa
Maria Fernanda Mendes; Silvia Balsimelli; Gabriela Stangehaus; Charles Peter Tilbery
The objective of the present study was to translate, to do cultural equivalence and validation of the Functional Assessment of Multiple Sclerosis quality of life instrument (FAMS) to Portuguese. The database analyzed is longitudinal, with 143 patients with clinically defined multiple sclerosis (MS). The validity of the scale was established by correlating total FAMS scores and sub-scales scores to EDSS
Invarianza de las ecuaciones de movimiento bajo transformaciones de escala espacio-temporales en la dinamica de Newton modificada (MOND)
NASA Astrophysics Data System (ADS)
Acosta, R.; Tuiran, E.; Molina Redondo, U.
The basic principles that originated the Modified Newtonian Dynamics MOND, are shown, as well as a description of the fundamentals aspects of the theory: modification of gravity and modification of inertia. Also, it is considered the behaviour of the movement equations under space-temporal scale transformations of the movement equations, that is, transformations that have the form (t, r) --> (lambda*t, r). It was observed in this way that the MOND regime comes from the requirement of the invariance of the movement equations with respect to this transformations.
Gerenciamento Baseado em Modelos da ConguraÁªo de Sistemas de SeguranÁa em Redes de Larga Escala
Holger Isenberg; Heiko Krumm; Paulo LÌcio de Geus
The security mechanisms employed in today's networked environments are increasingly complex and their congur ation management has an important role for the protection of these environments. Especially in large scale networks, security administrators are faced with the challenge of designing, deploying, maintaining and monitoring a huge number of mechanisms, most of which have complicated and heterogeneous congur ation syntaxes. A
Análisis factorial exploratorio y propiedades psicométricas de la escala de valencia de actitudes y creencias hacia la hipnosis, versión terapeuta
Antonio Capafons; Claudia Morales; Begoña Espejo; Sonia Cabañas
Exploratory factor analysis and psychometric properties of the valencia scale on attitudes and beliefs toward hypnosis. Therapist version. This investigation examines the psychometric properties and fac - tor structure of the Valencia Scale on Attitudes and Beliefs toward Hypnosis-Therapist version. Data from 775 professional psychologists belonging to the Spanish Association of Psychologists were used for the exploratory factor analysis (EFA).
Avaliação nutricional do milho com maior teor de óleo, nas formas de grãos secos e silagens, para suínos nas fases de crescimento e terminação
Marcos Augusto Alves da Silva; Antonio Claudio Furlan; Ivan Moreira; Diovani Paiano; Clóves Cabreira Jobim; Livia Carla Grigoletto Barcellos
Two experiments were carried out to determine nutritive value and verify performance of growing and finishing swine feed high moisture corn silage (HMCS) and reconstituted silage (RS) of higher oil corn. The digestibility assay was carried twelve cross breed barrow, were allotted in metabolism cages, in a completely randomized design. The values of digestible dry matter (DDM), digestible protein (DP),
Selfish Grids: Game-Theoretic Modeling and NAS\\/PSA Benchmark Evaluation
Yu-kwong Kwok; Kai Hwang; Shanshan Song
Selfish behaviors of individual machines in a grid can potentially damage the performance of the system as a whole. However, scrutinizing the grid by taking into account the noncooperativeness of machines is a largely unexplored research problem. In this paper, we first present a new hierarchical game-theoretic model of the grid that matches well with the physical administrative structure in
Picosecond carrier lifetimes in dilute GaInNAs grown on InP substrate
Mangeney, J.; Laurent, T.; Martin, M. [Institut d'Electronique Fondamentale, Univ. Paris-Sud, UMR 8622 CNRS, Orsay 91405 (France); Harmand, J. C.; Travers, L.; Mauguin, O. [CNRS/LPN, Laboratoire de Photonique et de Nanostructures, Marcoussis 91460 (France)
We study the carrier relaxation dynamics in Ga{sub 1-y}In{sub y} N{sub 0.03}As{sub 0.97} layers grown on InP substrate by molecular beam epitaxy. This dilute nitride semiconductor is a potential candidate for ultrafast components such as photoconductive terahertz devices driven at 1.55 {mu}m wavelength. Carrier lifetimes are measured by pump-probe experiments at 1550 nm wavelength and the shortest carrier lifetime is 2.6 ps under photoexcitation with {approx}4.2 {mu}J/cm{sup 2}. We observe two contributions in the differential transmittance decay. These contributions are discussed in terms of photocarrier recombination processes.
Implementation of BT, SP, LU, and FT of NAS Parallel Benchmarks in Java
NASA Technical Reports Server (NTRS)
Schultz, Matthew; Frumkin, Michael; Jin, Hao-Qiang; Yan, Jerry
A number of Java features make it an attractive but a debatable choice for High Performance Computing. We have implemented benchmarks working on single structured grid BT,SP,LU and FT in Java. The performance and scalability of the Java code shows that a significant improvement in Java compiler technology and in Java thread implementation are necessary for Java to compete with Fortran in HPC applications.
Materials Data on NaS2 (SG:122) by Materials Project
Kristin Persson
Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations
Evaluation of the Terminal Precision Scheduling and Spacing System for Near-Term NAS Application
NASA Technical Reports Server (NTRS)
Thipphavong, Jane; Martin, Lynne Hazel; Swenson, Harry N.; Lin, Paul; Nguyen, Jimmy
NASA has developed a capability for terminal area precision scheduling and spacing (TAPSS) to provide higher capacity and more efficiently manage arrivals during peak demand periods. This advanced technology is NASA's vision for the NextGen terminal metering capability. A set of human-in-the-loop experiments was conducted to evaluate the performance of the TAPSS system for near-term implementation. The experiments evaluated the TAPSS system under the current terminal routing infrastructure to validate operational feasibility. A second goal of the study was to measure the benefit of the Center and TRACON advisory tools to help prioritize the requirements for controller radar display enhancements. Simulation results indicate that using the TAPSS system provides benefits under current operations, supporting a 10% increase in airport throughput. Enhancements to Center decision support tools had limited impact on improving the efficiency of terminal operations, but did provide more fuel-efficient advisories to achieve scheduling conformance within 20 seconds. The TRACON controller decision support tools were found to provide the most benefit, by improving the precision in schedule conformance to within 20 seconds, reducing the number of arrivals having lateral path deviations by 50% and lowering subjective controller workload. Overall, the TAPSS system was found to successfully develop an achievable terminal arrival metering plan that was sustainable under heavy traffic demand levels and reduce the complexity of terminal operations when coupled with the use of the terminal controller advisory tools.
Lo, Martin
assembled by: JPL Technology Reporting Offke pp. i, l-3,la-lla for November 99 NASA TECH BRIEF Vol. 23, No, nor NASA, nor any person acting on behalf of NASA: a. Makes any warranty or representation, express a Kuiper Belt object can be transported to become a Jupiter comet, eventually evolving into an asteroid
BOREAS TE-9 In Situ Diurnal Gas Exchange of NAS Boreal Forest Stands
NASA Technical Reports Server (NTRS)
Hall, Forrest G. (Editor); Curd, Shelaine (Editor); Margolis, Hank; Coyea, Marie; Dang, Qinglai
The BOREAS TE-9 team collected several data sets related to chemical and photosynthetic properties of leaves in boreal forest tree species. The purpose of the BOREAS TE-09 study was threefold: 1) to provide in situ gas exchange data that will be used to validate models of photosynthetic responses to light, temperature, and carbon dioxide (CO2); 2) to compare the photosynthetic responses of different tree crown levels (upper and lower); and 3) to characterize the diurnal water potential curves for these sites to get an indication of the extent to which soil moisture supply to leaves might be limiting photosynthesis. The gas exchange data of the BOREAS NSA were collected to characterize diurnal gas exchange and water potential of two canopy levels of five boreal canopy cover types: young jack pine, old jack pine, old aspen, lowland old black spruce, and upland black spruce. These data were collected between 27-May-1994 and 17-Sep-1994. The data are provided in tabular ASCII files. The data files are available on a CD-ROM (see document number 20010000884), or from the Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC).
Observation of compositional fluctuations in GaNAs alloys grown by metalorganic vapor-phase epitaxy
NASA Astrophysics Data System (ADS)
Takahashi, Mitsuo; Moto, Akihiro; Tanaka, So; Tanabe, Tatsuya; Takagishi, Shigenori; Karatani, Kouichi; Nakayama, Masaaki; Matsuda, Kazunari; Saiki, Toshiharu
Photoluminescence (PL) spectra and scanning near-field optical microscope (SNOM) images have been measured at low temperature to investigate the compositional fluctuations in GaN xAs 1- x epilayers grown on GaAs by metalorganic vapor-phase epitaxy. Time-resolved PL has been employed to study the optical transitions and their dynamic processes. Our results suggest that the PL emission from GaN xAs 1- x epilayer at low temperature is dominated by localized exciton recombination induced by compositional fluctuations. Furthermore, we directly observed the distribution of the compositional inhomogeneity in the GaN xAs 1- x samples even with a small N-content of 0.5% by measuring SNOM images. The emission spot size of less than 1 ?m is estimated for the GaN xAs 1- x (N=0.5%) epilayer, and its size tends to decrease with increasing nitrogen concentration.
Strain-compensated GaInNAs structures for 1.3-?m lasers
Tomi Jouhti; Chang Si Peng; Emil-Mihai Pavelescu; Janne Konttinen; Luis Aguiar Gomes; Oleg G. Okhotnikov; Markus Pessa
GaAs-based dilute nitride lasers are potential light sources for future optical fiber communication systems at the wavelength of 1.3 ?m. In this paper we discuss the results of studies of optimization of the growth conditions and active regions of the GaAs-based lasers. To this end, a series of samples were grown using the molecular beam epitaxy technique. The active regions
Genesis. Author manuscript Nas transgenic mouse line allows visualization of Notch pathway activity
Paris-Sud XI, Université de
or apoptosis. Accordingly, genetic alterations of Notch pathway components have been implicated in various ; embryology ; metabolism ; Base Sequence ; Chromosomal Proteins, Non-Histone ; genetics ; Female ; Gene-Binding Protein ; genetics ; metabolism ; Lac Operon ; Male ; Mice ; Mice, Transgenic ; embryology ; physiology
Support of Activities of the NAS in Relation to the Radiation Effects Research Foundation
Douple, Evan B.
The National Academies (NA) provides support for the activities related to the long-term follow up of the health of the survivors of the atomic bombings of Hiroshima and Nagasaki being conducted by the Radiation Effects Research Foundation (RERF) laboratories in Hiroshima and Nagasaki, Japan. The NA serves as scientific and administrative liaison between the U.S. Department of Energy (DOE) and RERF, and performs tasks in the areas of scientific oversight, information/public interface, fiscal oversight, and personnel management. The project includes recruitment and support of approximately 10 NA employees who work at RERF in Japan. Specific activities are performed consistent with the cooperative agreement's Statement of Work between DOE and NA and consistent with an Annual Work Plan developed by DOE and NA.
48 CFR 852.236-82 - Payments under fixed-price construction contracts (without NAS).
Code of Federal Regulations, 2010 CFR
...promptly upon completion of all contract requirements, but nothing...under other provisions of the contract or in accordance with the general law and regulations regarding the administration of Government contracts. (b) The...
48 CFR 852.236-83 - Payments under fixed-price construction contracts (including NAS).
Code of Federal Regulations, 2010 CFR
...promptly upon completion of all contract requirements, but nothing...under other provisions of the contract or in accordance with the general law and regulations regarding the administration of Government contracts. (b) The...
An Integrated Approach to Evaluating Risk Mitigation Measures for UAV Operational Concepts in the NAS
Weibel, Roland E
An integrated approach is outlined in this paper to evaluate risks posed by operating Unmanned Aerial Vehicles in the National Airspace System. The approach supports the systematic evaluation of potential risk mitigation ...
NPB-MPJ: NAS Parallel Benchmarks Implementation for Message-Passing in Java
Touriño, Juan
in the performance evaluation of Java against C/Fortran parallel libraries on two representative multi-core clusters Java and native parallel solutions confirms that MPJ is an alternative for parallel programming multi-core. An interesting alternative is the use of Java for parallel programming multi-core systems. In fact, the Java
Determination of Nitrogen Concentration in Dilute GaNAs by STEM HAADF Z-Contrast Imaging
NASA Astrophysics Data System (ADS)
Grieb, Tim; Müller, Knut; Rubel, Oleg; Fritz, Rafael; Gloistein, Claas; Neugebohrn, Nils; Schowalter, Marco; Volz, Kerstin; Rosenauer, Andreas
We determine the nitrogen concentration of GaN0.01<=x<=0.05As1-x quantum wells by evaluation of high resolution scanning transmission electron microscopy (STEM) images using a high-angle annular dark field detector. Although nitrogen has a smaller atomic number than Ga the image intensity increases with the nitrogen content. This is explained by the influence of static atomic displacements by comparison with frozen lattice simulations. The resulting nitrogen concentrations agree with high resolution X-ray diffraction measurements and strain state analysis applied to STEM images.
Preliminary C3 Loading Analysis for Future High-Altitude Unmanned Aircraft in the NAS
NASA Technical Reports Server (NTRS)
Ho, Yan-Shek; Gheorghisor, Izabela; Box, Frank
This document provides a preliminary assessment and summary of the command, control, and communications (C(sup 3)) loading requirements of a generic future high-altitude, long-endurance unmanned aircraft (UA) operating at in the National Airspace System. Two principal types of C(sup 3) traffic are considered in our analysis: communications links providing air traffic services (ATS) to the UA and its human pilot, and the command and control data links enabling the pilot to operate the UA remotely. we have quantified the loading requirements of both types of traffic for two different assumed levels of UA autonomy. Our results indicate that the potential use of UA-borne relays for the ATS links, and the degree of autonomy exercised by the UA during the departure and arrival phases of its flight, will be among the key drivers of C(sup 3) loading and bandwidth requirements.
A Validation Study of Merging and Spacing Techniques in a NAS-Wide Simulation
NASA Technical Reports Server (NTRS)
Glaab, Patricia C.
In November 2010, Intelligent Automation, Inc. (IAI) delivered an M&S software tool to that allows system level studies of the complex terminal airspace with the ACES simulation. The software was evaluated against current day arrivals in the Atlanta TRACON using Atlanta's Hartsfield-Jackson International Airport (KATL) arrival schedules. Results of this validation effort are presented describing data sets, traffic flow assumptions and techniques, and arrival rate comparisons between reported landings at Atlanta versus simulated arrivals using the same traffic sets in ACES equipped with M&S. Initial results showed the simulated system capacity to be significantly below arrival capacity seen at KATL. Data was gathered for Atlanta using commercial airport and flight tracking websites (like FlightAware.com), and analyzed to insure compatible techniques were used for result reporting and comparison. TFM operators for Atlanta were consulted for tuning final simulation parameters and for guidance in flow management techniques during high volume operations. Using these modified parameters and incorporating TFM guidance for efficiencies in flowing aircraft, arrival capacity for KATL was matched for the simulation. Following this validation effort, a sensitivity study was conducted to measure the impact of variations in system parameters on the Atlanta airport arrival capacity.
UAS Integration into the NAS: HSI Full Mission Simulation Preliminary Results
NASA Technical Reports Server (NTRS)
Shively, Jay; Fern, Lisa; Rorie, Conrad
The goal of the Full Mission Sim was to examine the effects of different command and control interfaces on UAS pilots' ability to respond to ATC commands and traffic advisories. Results suggest that higher levels of automation (i.e., waypoint-to-waypoint control interfaces) lead to longer initial response times and longer edit times. The findings demonstrate the importance of providing pilots with interfaces that facilitate their ability to get back "in the loop."
Lattice parameter in GaNAs epilayers on GaAs: Deviation from Vegard's law
NASA Astrophysics Data System (ADS)
Li, Wei; Pessa, Markus; Likonen, Jari
The N content and lattice parameter of GaNxAs1-xepilayers on GaAs (0
UAS Integration in the NAS Project Overview: RTCA SC-228 Plenary DAA Working Group 5
NASA Technical Reports Server (NTRS)
Randall, Debra K.
The presentation is intended to allow the public to know and understand NASA's plans for integrated test to allow them the opportunity to provide feedback and suggestions. The integrated testing will support verification and validation of the RTCA SC-228 UAS minimum operation performance standard requirements.
Multi-agent Simulation of NAS Infrastructure Utilization in the Presence of Airline Policies
the safety rules (separation distances). Usually, aircraft wait on the ground until the controllers allow ]. This paper uses a multi-agent-based simulation to model aircraft operations and infrastructure utilization in the presence of airline policies and aircraft route selection strategies. The main hypothesis of the paper
In the interest of resolving scientific questions, the EPA, the Department of Defense, the Department of Energy, and the National Aeronautics and Space Administration - members of a broader Interagency Working Group on Perchlorate led by the Office of Science and Technology Polic...
Andréia Amaral Sant' Anna; Sílvio Menezes; César Augusto Soares da Costa
A falta de preocupação da população como um todo com a emissão de gases estufa, e a completa falta de entendimento do que está acontecendo em nosso planeta no momento em termos de aquecimento global e suas conseqüências foram a alavanca para este projeto que buscará envolver alunos e professores da rede municipal de ensino com a comunidade local
Complejidad descriptiva y computacional en m\\'aquinas de Turing peque\\~nas
Joosten, Joost J; Zenil, Hector
En este trabajo ofrecemos algunos de los resultados obtenidos al estudiar las funciones calculadas por m\\'aquinas de Turing con un alfabeto de dos s\\'imbolos y un n\\'umero de estados entre 1 y 3. Presentamos detenidamente el modelo de m\\'aquina de Turing empleado, donde la cinta es ilimitada en un solo sentido, y no existe estado de parada. Mostramos gr\\'aficamente c\\'omo es posible representar la funci\\'on calculada por una m\\'aquina, as\\'i como las computaciones realizadas para ello. Vemos que al aumentar el n\\'umero de estados, si bien es posible que algunas funciones se calculen con mayor rapidez, por lo general aumenta considerablemente el tiempo medio de computaci\\'on.
Carmem Aparecida Feijó; Elvio Valente
The aim of this paper is to discuss different theoretical definitions of the firm and compare them with the empirical definitions of the firm in economic surveys. We show that both, the empirical concept and the theoretical concept, have been changing along the time.
Minority carrier transport properties of GaInNAs heterojunction bipolar transistors with 2% nitrogen
Asbeck, Peter M.
% nitrogen Rebecca J. Welty,a) Huoping Xin, Charles W. Tu, and Peter M. Asbeck University of California) of 0.98 eV; this is achieved with a nitrogen composition of 2%. These devices have a turn-on voltage HFE is 8. The current gain of nitrogen containing HBTs is degraded due to the complex change
Razão e emoção: uma leitura analítico-comportamental de avanços recentes nas neurociências
Rosângela Araújo Darwich
Reason and emotion: a behavior-analytic interpretation of recent advances in neurosciences. Recent findings of the neurosciences present an integrated view of the human functioning, one that encompasses the relationships among the great organic systems, between physiological and cognitive states and between reason and emotion. The aim of this paper is to contrast such studies with central aspects of the Skinnerian
Avaliação de resíduos da fabricação de enzimas nas características químicas de um Cambissolo
Francisco Ribeiro; Rua Francisco Ribeiro; Ulisses José Ribeiro
Resumo - Os resíduos industriais e biossólidos reaproveitados na agricultura possuem potencial par a melhorar as características químicas e físicas do s olo, e evitando perda via reciclagem destes resíduos. Co m o objetivo de avaliar a utilização de substrato da fermentação microbiana inativado com Ca(OH) 2, oriundo da fabricação de enzimas industriais (proteases), sobre as características químicas do s
A Family of Well-Clear Boundary Models for the Integration of UAS in the NAS
Muñoz, César A.
a family of well-clear boundary models based on the TCAS II Resolution Advisory logic. For these models , mod TCAS II tau and modified tau tcpa Time to closest point of approach tep Time to entry point tcoa Self-Separation Volume TCAS Traffic Alerting and Collision Avoidance System TCPA Time to Closest Point
NASA Unmanned Aircraft Systems (UAS) Integration in the National Airspace System (NAS) Project [L2 Milestone
NASA Technical Reports Server (NTRS)
Denney, Ewen; Pai, Ganesh
In this document, we present an argument-based representation of the TCB for the URS, also highlighting the various components of safety of operations and the relevant interrelations. In particular, we give a modular argument architecture, which abstractly characterizes how the airworthiness requirements, i.e., the TCB, and additional requirements, e.g., procedures required from operators, together with the constraints on operations, relate to the broader concern of system safety; fragments of argument structures that realize the argument architecture, and which link a claim of safety of operations, through hazard identification and control, to airworthiness. This aspect is further refined into type design concerns, which are reflected as requirements that comprise the type certification basis. Thus, the fragments illustrate how structured arguments can communicate both the type certification basis as well as other requirements that have a bearing on safety.
NAS battery demonstration at American Electric Power:a study for the DOE energy storage program.
Newmiller, Jeff (Endecon Engineering, San Ramon, CA); Norris, Benjamin L. (Norris Energy Consulting Company, Martinez, CA); Peek, Georgianne Huff
The first U.S. demonstration of the NGK sodium/sulfur battery technology was launched in August 2002 when a prototype system was installed at a commercial office building in Gahanna, Ohio. American Electric Power served as the host utility that provided the office space and technical support throughout the project. The system was used to both reduce demand peaks (peak-shaving operation) and to mitigate grid power disturbances (power quality operation) at the demonstration site. This report documents the results of the demonstration, provides an economic analysis of a commercial sodium/sulfur battery energy storage system at a typical site, and describes a side-by-side demonstration of the capabilities of the sodium/sulfur battery system, a lead-acid battery system, and a flywheel-based energy storage system in a power quality application.
Polymers: Technical activities, 1991. NAS-NRC Assessment Panel, February 13-14, 1992
Smith, L.E.; Fanconi, B.M.
All of the Division's programs are described in the report, organized according to these six Groups. These Groups have made a number of significant accomplishments during the last year. Some of these are summarized below: A computer simulation was performed to model resin flow in liquid molding of the front end structure of a Ford Escort; A NIST/industry consortium has evolved for the purpose of developing in-line measurement technology based on optical and fluorescence methods; A combined light scattering photometer/rheometer has been constructed to examine phase separation behavior of polymer blends and solutions under the influence of a simple shear field; A unique new tool has been developed to study the physics involved in the adhesion between a polymer and a solid surface like glass; The distribution of polarization in poly(vinylidene fluoride) poled by corona discharge rather than by contacting electrodes indicated positive charge injection near the surface; Proton spin diffusion results indicated domain sizes in poly(butylmethacrylate)/hydroxy modified polystyrene blends with minimum dimensions in the 6-10 nm range and stoichiometries of the order of 75/25; Novel, siloxane-containing difunctional and multifunctional vinyl monomers were prepared; The apparent 'shift' in polymer blend phase separation temperature, Tc, under shear flow has been interpreted with the mode-coupling theory for mean-field polymer blend systems; The radial flow behavior was successfully predicted from measurements in unidirectional flow; An exposure technique that rapidly determines whether or not a polymer is biodegradable has been developed; Instrumentation has been set up and calibrated to measure the dielectric constant of thin polymer films at high electric fields; A viscoelastic model of stresses in porcelain-metal strips has been developed.
ESTANDARIZACIÓN DE LA ESCALA STANFORD DE SUSCEPTIBILIDAD HIPNÓTICA, FORMA C, EN UNA MUESTRA MEXICANA Standardization of the Stanford Hypnotic Susceptibility Scale, Form C in a Mexican Sample
Omar Sánchez-Armáss; Arreed F. Barabasz; Marianne Barabasz
This article briefly describes a historical review of the study and clinical application of hypnosis. Normative data of the Stanford Hypnotic Suscepti- bility Scale, Form C (SHSS:C) in a sample of 513 Mexican volunteers is pre- sented. The psychometric properties of the scale are reported and compared with the pro-perties presented by normative studies conducted in USA, Italy, Germany, Holland
Características psicométricas de las versiones americana y española de la escala TDA-H (Trastorno por Déficit de Atención con Hiperactividad): un estudio comparativo
Nekane Balluerka; Juana Gómez; William A. Stock; Linda C. Caterino
El presente artículo se centra en el estudio psicométrico de una es- cala para el diagnóstico del Tr a s t o rno por Déficit de Atención con H i p e ra c t ividad en adultos. Dicho tra s t o rno fue descubierto a pri n c i- pios de siglo en la población infantil por un
Andreu Blesa; Inés Küster; J. Enrique Bigné; Luisa Andreu
The study focuses on the analysis of market orientation and its effects on two of the most significant sectors in the Valencian Community: the ceramics sector and the tourism sector. Particularly, there arises the need for companies in these sectors to adopt market orientation as a management model, with the aim of improving their results. For this purpose, a scale
Defects in Ga(In)NAs thin films grown by atomic H-assisted molecular beam epitaxy
Shimizu, Yukiko; Mura, Yusuke; Uedono, Akira; Okada, Yoshitaka [Institute of Applied Physics, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8573 (Japan)
The vacancy-type defects in Ga{sub 1-y}In{sub y}N{sub x}As{sub 1-x} dilute nitride films grown by atomic H-assisted molecular beam epitaxy (H-MBE) were investigated. The positron annihilation measurements showed that the densities of vacancy-type defects in GaN{sub x}As{sub 1-x} (x=0%-1.3%) films grown under an optimized atomic H flux were as low as that for a liquid encapsulated Czochralski (LEC) GaAs substrate. Further, the influence of vacancy-type defects on the crystal quality and optical properties were studied by x-ray diffraction and photoluminescence (PL) measurements. The integrated PL intensity at 77 K drastically decreased as N composition was increased, but we found no clear correlation between the density or volume of vacancy defects and optical properties, and the S parameters were nearly constant at a value of {approx}0.516 in all Ga{sub 1-y}In{sub y}N{sub x}As{sub 1-x} films grown by our H-MBE technique.
Proceedings of Institute of Mathematics of NAS of Ukraine 2004, Vol. 50, Part 2, 708714 Irreducible Killing Tensors
Popovych, Roman
Â714 Irreducible Killing Tensors from Conformal Killing Vectors S. Brian EDGAR , Rafaelle RANI and Alan BARNES methods to construct reducible proper conformal Killing tensors and Killing tensors (which are, in general, irreducible) when a pair of orthogonal conformal Killing vectors exist in a given space. We give
Multiple stacking of self-assembled InAs quantum dots embedded by GaNAs strain compensating layers
Ryuji Oshima; Takayuki Hashimoto; Hidemi Shigekawa; Yoshitaka Okada
We have investigated a growth technique to realize high-quality multiple stacking of self-assembled InAs quantum dots (QDs) on GaAs (001) substrates, in which GaNxAs1-x dilute nitride material was used as a strain compensation layer (SCL). The growth was achieved by atomic hydrogen-assisted rf molecular beam epitaxy, and the effect of strain compensation was systematically investigated by using high-resolution x-ray diffraction
A Biometric Latent Curve Analysis of Memory Decline in Older Men of the NAS-NRC Twin Registry
McArdle, John J.; Plassman, Brenda L.
Previous research has shown cognitive abilities to have different biometric patterns of age-changes. Here we examined the variation in episodic memory (Words Recalled) for over 6,000 twin pairs who were initially aged 59-75, and were subsequently re-assessed up to three more times over 12 years. In cross-sectional analyses, variation in Education was explained by strong additive genetic influences (~43%) together with shared family influences (~35%) that were independent of age. The longitudinal phenotypic analysis of the Word Recall task showed systematic linear declines over age, but with positive influences of Education and Retesting. The longitudinal biometric estimation yielded: (a) A separation of non-shared environmental influences and transient measurement error (~50%): (b) Strong additive genetic components of this latent curve (~70% at age 60) with increases over age that reach about 90% by age 90. (c) The minor influences of shared family environment (~17% at age 60) were effectively eliminated by age 75. (d) Non-shared environmental effects play an important role over most of the life-span (peak of 42% at age 70) but their relative role diminishes after age 75. PMID:19404731
Forma física da ração e pesos de abate nas características de carcaça de cordeiros em creep feeding
Marcela Abbado Neres; Alda Lúcia Gomes Monteiro; Cledson Augusto Garcia; Ciniro Costa; Mário de Beni Arrigoni; Guilherme Jordão Magalhães Rosa
Twenty 3\\/4 Suffolk male lambs were fed ground and pelleted diets and slaughtered at 26 and 28 kg of liveweight. Diets were isoprotein (21% CP) and isoenergetic (2.9 Mcal ME\\/kg DM). Lambs had free entrance on creep feeding, staying with their mothers until reaching slaughter weight. Pelleted diet resulted in higher hot dressing-out percentages (54.18% for pelleted diet and 52.04%
GaInNAs-based Hellish-vertical cavity semiconductor optical amplifier for 1.3 ?m operation
Faten Adel Ismail Chaqmaqchee; Simone Mazzucato; Murat Oduncuoglu; Naci Balkan; Yun Sun; Mustafa Gunes; Maxime Hugues; Mark Hopkinson
Hot electron light emission and lasing in semiconductor heterostructure (Hellish) devices are surface emitters the operation of which is based on the longitudinal injection of electrons and holes in the active region. These devices can be designed to be used as vertical cavity surface emitting laser or, as in this study, as a vertical cavity semiconductor optical amplifier (VCSOA). This
Proceedings of Institute of Mathematics of NAS of Ukraine 2002, Vol. 43, Part 1, 149150 Symmetry of Nonlinear Schrodinger Equations
Popovych, Roman
of equation (1) is Aker = t, Jab, M . The Lie algebra of the kernel of principal groups of equation (1) for fixed k is 1) Aker 0 = t, a, Jab, G, M in the case k = 0; 2) Aker - = M, t, Jab, e2t (a + xa M), e-2t (a - xa M) in the case k = -2 , > 0; 3) Aker + = M, t, Jab, sin 2t a + xa cos 2t M, cos 2t a - xa sin 2t
Proceedings of Institute of Mathematics of NAS of Ukraine 2000, Vol. 30, Part 1, 245248. On Symmetry of a Class
Popovych, Roman
was studied in [4] and can be described by the following basis operators: P0 = t, Pa = a, Pu = u, Jab = xab, -1, . . . , -1), JAB = xAB - xBA, D = xAA, KA = 2xAD - xBxBA, where A, B = 0, 1, 2, . . . , n + 1; xn
Estudo eletromiográfico dos músculos isquiotibiais (bíceps femoral porção longa, semitendinoso, e semimembranoso) nas atividades: ciclismo, musculação e esteira ergométrica
Antonia Dalla; Pria Bankoff
The hamstrings muscles (femoris biceps long head, semitendinosus and semimembranosus), had been studied through the electromyography in 18 male individuals, age group between 19 and 25 years old, average of age 22,8 years old, through the electromyography, with the purpose to verify the potential the action in the following activities: cyclism, muscular activity and treadmill . The work was developed
78 FR 12951 - TRICARE; Elimination of the Non-Availability Statement (NAS) Requirement for Non-Emergency...
Federal Register 2010, 2011, 2012, 2013, 2014
...Non-Emergency Inpatient Mental Health Care AGENCY: Office of the Secretary...non-emergency inpatient mental health care in order for a TRICARE Standard...non-emergency inpatient mental health care for TRICARE Standard...
Considerations in the Integration of Small Aircraft Transportation System Higher Volume Operations (SATSHVO) in the National Airspace System (NAS)
NASA Technical Reports Server (NTRS)
Lohr, Gary W.; Williams, Dan; Abbott, Terence; Baxley, Brian; Greco, Adam; Ridgway, Richard
The Small Aircraft Transportation System Higher Volume Operations (SATS HVO) concept holds the promise for increased efficiency and throughput at many of the nations under-used airports. This concept allows for concurrent operations at uncontrolled airports that under today s procedures are restricted to one arrival or one departure operation at a time, when current-day IFR separation standards are applied. To allow for concurrent operations, SATS HVO proposes several fundamental changes to today's system. These changes include: creation of dedicated airspace, development of new procedures and communications (phraseologies), and assignment of roles and responsibilities for pilots and controllers, among others. These changes would affect operations on the airborne side (pilot) as well as the groundside (controller and air traffic flow process). The focus of this paper is to discuss some of the issues and potential problems that have been considered in the development of the SATS HVO concept, in particular from the ground side perspective. Reasonable solutions to the issues raised here have been proposed by the SATS HVO team, and are discussed in this paper.
Proceedings of Institute of Mathematics of NAS of Ukraine 2004, Vol. 50, Part 3, 14151422 Visualisation and Animation
Popovych, Roman
1422 Visualisation and Animation in Mathematics and Physics Eberhard MALKOWSKY Department of Mathematics, email@example.com We give some applications of our own software for geometry and differential geometry and its extensions [5,1,2,4,69] to the visualisation and animation of certain topics in mathematics and physics
Proceedings of Institute of Mathematics of NAS of Ukraine 2002, Vol. 43, Part 1, 194200 Heat Equation on Riemann Manifolds
Popovych, Roman
for the heat equation case. The category of second order parabolic equations posed on arbitrary manifolds is considered. In this category, for the given nonlinear heat equation we could find morphisms from it to other" representatives) is carried out. Necessary and sufficient conditions for canonical morphisms of heat equation
O Planejamento Estratégico nas Instituições de Ensino Superior dos Cursos de Administração do Estado de São Paulo
The article is a description search done with the Business Administration courses from the São Paulo State Universities, aiming to identify if these organizations are using the formal strategic planing as being one of the organizational management tools. Based on the literature revision about strategic planing process and one search questions answered by the universities, was possible to identify the
Lidiane Parente Andrade; Daniel Nelo Soares; Mauro Margalho Coutinho; Antônio Jorge; Gomes Abelém
The 802.11x standard for wireless network has been widely adopted by large corporations and institutions during its daily tasks, forasmuch the productivity increase produced by flexibility and mobility found in these new sorts of wireless equipments have provided great operational advantages. Nevertheless, there are some important security issues that should be take in consideration while using this new technology. Having
Proceedings of Institute of Mathematics of NAS of Ukraine 2004, Vol. 50, Part 3, 14421447 Axially Symmetric Black Hole Skyrmions
Popovych, Roman
Symmetric Black Hole Skyrmions Nobuyuki SAWADO and Noriko SHIIKI Department of Physics, Tokyo University of Science, Noda, Chiba 278-8510, Japan E-mail: firstname.lastname@example.com, email@example.com It has and obtain static axially symmetric black hole solutions nume- rically. The black hole skyrmion no longer has
Economics and politics in the assessment of causes of building illness: The NAS/NRC Report on Indoor Pollutants
Sterling, T.D.
How do some health scientists manage to avoid obvious antecedents of disease that are centered in the workplace. The 1981 National Academy of Sciences/National Research Council (NAC/NRC) report entitled Indoor Pollutants is analyzed as an example of this avoidance. Although the report contributes to the understanding of technical problems of indoor pollution, its orientation and some of its conclusions are difficult to reconcile with known scientific findings. Reports of investigations done in response to complaints of white-collar workers are largely ignored, as are reports showing hazardously high carbon monoxide levels from cooking in the home and accounts of misuse of gas ranges for supplemental home heating on the part of low-income families. The major blame for indoor pollution is placed on human behavior, especially smoking; however, most investigations of building illness find not tobacco smoke but inadequate ventilation to be the major source of illness. The report demonstrates the limited viewpoint that continues to ignore the productive processes that dominate social relationships, including the economic and political forces that determine workers' activities and their work environment. Continuance of such an approach will hinder future investigations as to the true causes of building illness and detract from efforts to assign the proper social responsibilities for effecting the changes necessary to reduce health risks for white-collar workers.
by climate) chaparral-shrubland, grassland. Discrimination will be based on canopy bi-directional reflectance properties, seasonal phenology and surface climate. (2) develop a simple ecosystem process model for each of these biomes, BIOME-BGC based on the logic of the current FOREST-BGC; (3) relate the seasonal trend of weekly composite NDVI to vegetation phenology and temperature limits to develop a satellite defined growing
Proceedings of Institute of Mathematics of NAS of Ukraine 2000, Vol. 30, Part 1, 3546. Computer Package for Investigation
Popovych, Roman
with the global name vard. For example, if we deal with the jet space J(R, R2) with the local coordinates (x, ui, vi) then we must assign vard:=[u, v]:. Then the coordinates in all programs will be denoted as x, u0. The following example shows the difference between the built-in and our procedures: #12;36 A.G. Meshkov > vard
Proceedings of Institute of Mathematics of NAS of Ukraine 2002, Vol. 43, Part 2, 569576 Point Form Relativistic Quantum Mechanics
Popovych, Roman
. It is well known that the number of independent form factors in elastic scattering is equal to 2s + 1, where ,(RW ), (4) with RW a Wigner rotation defined by RW = B-1(v)B(v), and B(v) a canonical spin (ro Relativistic Quantum Mechanics and an Algebraic Formulation of Electron Scattering W.H. KLINK Department
Effects of rapid thermal annealing conditions on GaInNAs band gap blueshift and photoluminescence intensity
Keller, Ursula
Electronics, Wolfgang-Pauli-Strasse 16, CH-8093 Zürich, Switzerland S. Schön ETH Zurich, FIRST Center for Micro- and Nanoscience, Wolfgang-Pauli-Strasse 10, CH-8093 Zürich, Switzerland Received 7 December 2005
Fabrication of GaInNAs-based Solar Cells for Application to Multi-junction Tandem Solar Cells
Naoya Miyashita; Yukiko Shimizu; Naoto Kobayashi; Yoshitaka Okada; Masafumi Yamaguchi
We have investigated the characteristics of p-GaAs\\/i-n-Ga0.97 In0.03N0.01As0.99 heterojunction solar cells with different intrinsic layer thickness. The solar cells studied in this study were fabricated by atomic hydrogen-assisted RF-MBE on GaAs(001) substrates. With an optimized i-layer thickness of 600nm, maximum quantum efficiency of > 80% has been obtained, and the hole diffusion length in n-Ga0.97In0.03N0.01As0.99 film was ~160nm. Then we
Alberto Silva Dutra; Joao Armando Dessimon Machado; Regis Rathmann
O processo de globalização e a abertura comercial brasileira são fenômenos que contribuem para explicar a maior complexidade característica ao ambiente no qual o produtor rural está inserido, exigindo deste agente maior dinamismo e capacidade adaptativa no que tange à estruturação de suas estratégias e ao seu processo de tomada de decisão. Fica evidenciada, neste contexto, a necessidade de uma
75 FR 35800 - Draft EPA's Reanalysis of Key Issues Related to Dioxin Toxicity and Response to NAS Comments
Federal Register 2010, 2011, 2012, 2013, 2014
...Assessment (NCEA) within the EPA Office of Research and Development (ORD). The draft document...will convene an expert panel composed of scientists knowledgeable about technical issues...peer review under applicable information quality guidelines. This draft report has...
Proceedings of Institute of Mathematics of NAS of Ukraine 2004, Vol. 50, Part 2, 923930 Symmetries in Semiclassical Mechanics
Popovych, Roman
transformation is evolution. Group of Poincar´e transformations is also a typical example of symmetry group. More, the symmetry notions are similar. For example, the evolution is viewed as a transformation mapping the initial transformation of the classical state space (phase space) generated by a Hamiltonian vector field (see
75 FR 33615 - Draft EPA's Reanalysis of Key Issues Related to Dioxin Toxicity and Response to NAS Comments (EPA...
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...public comment period and before the external peer review meeting. EPA welcomes the...assessment in response to the independent external peer review and public comments. All...exposure to chemical substances found in the environment. Through the IRIS Program, EPA...
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Reconstrução tridimensional de arcos magnéticos por tomografia
NASA Astrophysics Data System (ADS)
Simões, P. J. A.; Costa, J. E. R.
Uma explosão solar é uma variação súbita do brilho que ocorre nas regiões ativas da atmosfera solar. Estas regiões são constituídas por um plasma magnetizado com intensa indução magnética e em cenários bem complexos como visto recentemente através de experimentos embarcados em satélites operando instrumentos em raios X moles e ultra-violeta distante. A energia magnética, que pode ser armazenada por um período de horas até dias em configurações magnéticas estressadas, é subitamente lançada na atmosfera solar e transferida para partículas como elétrons, prótons e núcleos pesados, que são acelerados e/ou aquecidos, produzindo radiação eletromagnética. A proposta final deste projeto é determinar as características espaciais de alta resolução da emissão e polarização girossincrotrônica de explosões solares em ambientes complexos de campos magnéticos. Os recentes resultados da emissão difusa em EUV apresentado pelos satélites TRACE e SOHO dos arcos magnéticos conectando as diferentes polaridades magnéticas sobre as regiões ativas possibilitam novas abordagens sobre o papel do campo magnético na emissão em rádio. Nesta etapa apresentamos os resultados da reconstrução da geometria tridimensional das linhas de força destes arcos utilizando técnicas tomográficas, a partir de imagens de alta resolução espacial obtidas pelo instrumento EIT (Extreme ultraviolet Imaging Telescope), além da modelagem das induções magnéticas por um campo dipolar e as densidades de partículas aceleradas. Utilizamos para a reconstrução geométrica, imagens tomadas em vários ângulos dos arcos devido à rotacão solar. Com estes resultados, daremos continuidade ao projeto, com os cálculos da transferência radiativa nos modos ordinário e extraordinário de propagação da radiação girossincrotrônica de explosões solares.
Sesso Temtica: Sensoriamento Remoto aplicado quantificao de riscos de queimadas nos Trpicos: da deteco a aplicaes de grande-escala. (Remote Sensing of fire hazard in the Tropics: from detection to large-scale applications).
, its relationship with climate, forecasts and regional and global impacts. By the end of this workshop for detecting and monitoring fires, as well as the quantification of its impacts in the ecosystems. This workshop aims to provide an overview on the monitoring, the impacts quantification and forecast of extreme
Changes in concentration of nitrogenous compounds during fermentation of white grape musts at pilot plant scale\\/Cambios en la concentración de compuestos nitrogenados durante la fermentación de mosto a escala piloto
M. Dizy; M. C. Polo
Five vinifications were performed in 500 L tanks using two musts of the Malvar white grape variety. Four vinifications were carried out with or without the addition of sulphur dioxide by spontaneous fermentation and by a mixed culture of yeasts (Kloeckera apiculata, Torulaspora delbrueckii and Saccharomyces cerevisiae var ellipsoideus). A fifth experiment was performed with the addition of sulphur dioxide
Characterization of water pathways in low permeable rocks at the rock matrix scale: Methodological review Caracterización de las vías de circulación del agua, a la escala de la matriz rocosa, en rocas de baja permeabilidad. Revisión metodológica
M. Montoto; F. Mateos
This is a methodological paper related to the characterization of water pathways, at the rock matrix or intact rock scale, in crysta- lline rocks candidate for the final disposal of high level radioactive wastes. At that scale, water circulation in these rocks is basically conditioned by its capacity to flow through the open effective porosity. That is, through the connected
INFLUÊNCIA DO TIPO DE VEGETAÇÃO NAS POPULAÇÕES DE AVES EM UMA FLORESTA IMPLANTADA DE Pinus spp, NA REGIÃO DE AGUDOS, SP
Alvaro Fernando de Almeida
O. D. C. 156:174.7 Pinus spp SUMMARY The author studied a bird community through the capture marking and recapture in a man made Pinus forest. The populations were compared in the internal natural vegetations, in the man made Pinus and native species forests and in the external («cerrado»). The birds penetration in the man made forests is discussed according to
Proceedings of Institute of Mathematics of NAS of Ukraine 2000, Vol. 30, Part 1, 6067. Electro-Static Potential Between Two Conducting
Popovych, Roman
The Laplace equation arises in many branches of physics, from which it attracts a wide band of researchers-plane. The application of one- parameter group reduces the number of independent variables by one, and consequently a source to a load. This may be a transmitter and an antenna, a shift register and the memory core
Photoluminescence study of InAs quantum dots embedded in GaNAs strain compensating layer grown by metalorganic-molecular-beam epitaxy
X. Q. Zhang; Sasikala Ganapathy; Hidekazu Kumano; Kasturi Uesugi; Ikuo Suemune
Self-assembled InAs quantum dots (QDs) embedded in GaN0.007As0.993 strain compensating layers have been grown by metalorganic-molecular-beam epitaxy on a GaAs (001) substrate with a high density of 1×1011 cm-2. The photoluminescence properties have been studied for two periods of InAs quantum dots layers embedded in GaN0.007As0.993 strain compensating layers. Four well-resolved excited-state peaks in the photoluminescence spectra have been observed
Review of the NAS/NRC report: {open_quotes}Groundwater at Yucca Mountain: How high can it rise?{close_quotes}. Special report No. 1
Archambeau, C.B.
There are three basic and serious problems that produce disagreement with the conclusions and recommendations of the Academy report entitled {open_quotes}Groundwater at Yucca Mountain: How high can it rise?{close_quotes}. These are: First, the report ignores a considerable body of critical data relating to the ages and nature of hydrothermal alterations at the site; second, many of the strong conclusions expressed in the report are not reasonably supported by the evidence presented and, in some cases, are inconsistent with data and results available to the committee but which are not cited or used by them; and finally, there are statements describing field relationships and data that are not consistent with the facts or are made in such a way as to be misleading.
A long term (1989-1994) experiment with sugar cane (RB 739735) was carried out, in Linhares, ES, Brazil, in order to evaluate the effect of two systems of sugar cane harvesting: the first with previous burning (burned cane), and the second with crop residue remaining on the soil surface (green cane), on some physical properties of a tableland Yellow Podzolic soil.
Podemos considerar que os nossos eventos comearam em 1979, quando foi realizado o primeiro encontro de qumicos tericos nas dependncias do CBPF, no Rio de Janeiro, que
Ferreira, Márcia M. C.
#12;Apoio: #12;Podemos considerar que os nossos eventos começaram em 1979, quando foi realizado o SBQT em 1981 e daí por diante, há cada dois anos, até este momento em que realizamos o XIII SBQT. Ao um reconhecimento internacional, comprovado pelas publicações em periódicos qualificados como o
Proceedings of Institute of Mathematics of NAS of Ukraine 2004, Vol. 50, Part 1, 170175 Towards the Group Classification of Control Systems
Popovych, Roman
the Group Classification of Control Systems Victor I. LEHENKYI and Joachim RUDOLPH Institute classification for the second-order control systems. 1 Introduction Recently there has been quite a few publications dealing with the symmetries of control systems. Nevertheless, most of them deal with particular
Proceedings of Institute of Mathematics of NAS of Ukraine 2000, Vol. 30, Part 1, 8389. On Exact Solutions of the Nonlinear Heat
Popovych, Roman
of the extended Euclidean algebras A ~E(1) = P0, D1 and A ~E(3) = Pa, Jab, D2 : a, b = 1, 2, 3 , generated by the vector fields [8]: P0 = e-µx0 x0 + µv v , D1 = 1 µ x0 , Pa = xa , Jab = xa xb - xb xa , D2 = xa xa) and the conformal algebra AC(3) = Pa, Ka, Jab, D2 : a, b = 1, 2, 3 , where P0, Pa, Jab, D2 are vector fields (3
Proceedings of Institute of Mathematics of NAS of Ukraine 2000, Vol. 30, Part 1, 99102. On Galilei Invariance of Continuity Equation
Popovych, Roman
operators (2) contains as subalgebras the general- ized Galilei algebra AG2(1, n) = Pµ, Jab, Ga, D(1) , A (3) and the conformal algebra AP2(1, n) = AC(1, n) = Pµ, Jab, J0a, D(2) , Kµ . (4) We use the following designations in (3) and (4) Pµ = µ, Jab = xab - xba + jajb - jbja (a
UAS-NAS Live Virtual Constructive Distributed Environment (LVC): LVC Gateway, Gateway Toolbox, Gateway Data Logger (GDL), SaaProc Software Design Description
NASA Technical Reports Server (NTRS)
Jovic, Srboljub
This document provides the software design description for the two core software components, the LVC Gateway, the LVC Gateway Toolbox, and two participants, the LVC Gateway Data Logger and the SAA Processor (SaaProc).
Passivo ambiental: estudo de caso da Petróleo Brasileiro S.A - Petrobrás. A repercussão ambiental nas demonstrações contábeis, em conseqüência dos acidentes ocorridos
Ana Lúcia Bertoli; Maisa de Souza Ribeiro
Financial statements are very important for stockholders, investors, suppliers, funders and interested parties to know about the equity situation and result of a company, as well as how it relates to the environment, its commitment to nature and to current legislation. The absence of this information or the inexistence of its segregation can hide the impact of proactive or reactive
Proceedings of Institute of Mathematics of NAS of Ukraine 2004, Vol. 50, Part 3, 10611063 On Finiteness of Critical Tits Forms of Posets
Popovych, Roman
Â1063 On Finiteness of Critical Tits Forms of Posets Vitalij M. BONDARENKO and Andrij M. POLISHCHUK firstname.lastname@example.com In the paper we consider the Tits form of (finite and infinite) posets. We call such a form critical (with that a critical Tits form is finite (i.e. is of the Tits form of a finite poset). The quadratic Tits form
Proceedings of Institute of Mathematics of NAS of Ukraine 2004, Vol. 50, Part 1, 341347 Asymptotic Irrelevance of the KdV Hierarchy
Popovych, Roman
the "interaction" is sum of two-body forces, what is the key for the solubility of these equations in the first data; the norming constants cj localise the bound states; there are position (soft data), not spectral
COMPORTAMENTO E P ARÂMETROS FISIOLÓGICOS DE LEITÕES NAS PRIMEIRAS 24 HORAS DE VIDA Valuation of behavior and physiologic parameters of the first 24 hours of sucking pigs life
Rony Antonio Ferreira; Julien Chiquieri; Pedro Pierro Mendonça; Thiago Vasconcelos Melo; Mariana Duran Cordeiro; Rita da Trindade; Ribeiro Nobre Soares
An experiment was carried out in the swine sector of North Fluminense State University to evaluate the behavior and physiological parameters of piglets in the first 24 hours of life. A total of 82 growing piglets from commercial genetic lines were used. Observations of individual piglet behavior were made each five minutes. Rectal and superficial temperature of the piglets were
Comportamento da Cultura de Escarola Cultivada em Solo e Hidroponia Tipo NFT, no Trópico Úmido, nas Condições de Belém-Pará
Sérgio Antonio; Walter Vellasco; Duarte Silvestre; Mônica Trindade; Paulo Roberto de Andrade; Márcia Maria Braga da Rocha
Behavior of the endive culture in soil and hydroponic in the Amazonian conditions. The objective of the work was to evaluate the behavior of the endive culture (Cichorium endivia), in the field and NFT hydroponic conditions in Amazonian, area characterized by high temperatures and frequent rains. The experiment was driven in the Nucleo de Capacitação e Pesquisa em Horticultura of
A description of work accomplished under Contract NAS 7-100 between the California Institute of Technology and the National Aeronautics and Space Administration
Waliser, Duane E.
Other Activities 33 Jet Propulsion Laboratory California Institute of Technology 4800 Oak Grove Drive with the partic- ipation of the Jet Propulsion Laboratory in major u. S. space flights. In January, the Laboratory. Having made significant contributions to the early stages of space exploration, the Jet Propulsion Labora
An analysis of Hall mobility in as-grown and annealed n- and p-type modulation-doped GaInNAs/GaAs quantum wells
In this study, we investigate the effect of annealing and nitrogen amount on electronic transport properties in n- and p-type-doped Ga0.68In0.32NyAs1 ? y/GaAs quantum well (QW) structures with y?=?0%, 0.9%, 1.2%, 1.7%. The samples are thermal annealed at 700°C for 60 and 600 s, and Hall effect measurements have been performed between 10 and 300 K. Drastic decrease is observed in the electron mobility of n-type N-containing samples due to the possible N-induced scattering mechanisms and increasing effect mass of the alloy. The temperature dependence of electron mobility has an almost temperature insensitive characteristic, whereas for p-type samples hole mobility is decreased drastically at T?>?120 K. As N concentration is increased, the hole mobility also increased as a reason of decreasing lattice mismatch. Screening effect of N-related alloy scattering over phonon scattering in n-type samples may be the reason of the temperature-insensitive electron mobility. At low temperature regime, hole mobility is higher than electron mobility by a factor of 3 to 4. However, at high temperatures (T?>?120 K), the mobility of p-type samples is restricted by the scattering of the optical phonons. Because the valance band discontinuity is smaller compared to the conduction band, thermionic transport of holes from QW to the barrier material, GaAs, also contributes to the mobility at high temperatures that results in a decrease in mobility. The hole mobility results of as-grown samples do not show a systematic behavior, while annealed samples do, depending on N concentration. Thermal annealing does not show a significant improvement of electron mobility. PMID:23009196
Avaliação da aptidão para fritura de cultivares de batata, obtidas no cultivo de outono, nas regiões Sul e Campos das Vertentes de Minas Gerais
Joaquim Gonçalves de Pádua; Renata Vieira da Mota; Jaime Duarte Filho; Csaignon Mariano Caproni
Evaluation of the aptitude for fry of potato cultivars, obtained in the autumn crop, in the South and Campos das Vertentes areas of Minas Gerais state. The characteristics chemistries of the tubers and the development of the color after the fry were evaluated in potatoes cultivars introduced of Holland, when cultivated in the autumn, in the South and Campos das
Teaching of Astronomy at Teresa Martin College. (Breton Title: Ensino de Astronomia Nas Faculdades Teresa Martin.) Enseñanza de la Astronomia en la Facultad Teresa Martin
NASA Astrophysics Data System (ADS)
Azevedo Sobreira, Paulo Henrique
Courses with exclusive Astronomy contents did not exist at (FATEMA) Teresa Martin College's program until the end of 2002. In 2001, a series of educational experiments started in courses and classes of Astronomy at Mathematics and Geography departments. This actions culminated with the insertion of Teaching of Astronomy as a study theme in the course of Independent Studies for Mathematics professors in 2005. Até o final de 2002 inexistiam na grade curricular das Faculdades Integradas Teresa Martin (FATEMA) cadeiras com conteúdos exclusivos de Astronomia. A partir do ano de 2001 iniciou-se uma série de experiências educacionais através de modelos de cursos e de aulas de Astronomia nos Departamentos de Matemática e de Geografia, o que culminou com a inserção do Ensino de Astronomia como temática da disciplina de Estudos Independentes para o curso de Licenciatura em Matemática, em 2005. Hasta el final de 2002 no había en el currículo dela Facultad TeresaMartín (FATEMA) en San Pablo – SP, Brasil, disciplinas con contenidos exclusivos de Astronomía. A partir del año 2001 comenzó una secuencia de experimentos educacionales de carrera y de clases de Astronomía en los Departamentos de Matemática y Geografía, culminando en la implantación de clases de Enseñanza dela Astronomíaenla Licenciaturaen Matemática, en el año de 2003, y de la cátedra de extensión en Cosmografía parala Licenciaturaen Geografía.
Proceedings of Institute of Mathematics of NAS of Ukraine 2002, Vol. 43, Part 1, 344351 Boussineq-Type Equations and "Switching" Solitons
Popovych, Roman
-Type Equations and "Switching" Solitons Allen PARKER and John Michael DYE Department of Engineering MathematicsKupershmidt equation. These solitons have the unusual property that they "switch" shape on switching their direction the remarkable property that it "switches" shape on switching its direction of propagation. In this paper
Proceedings of Institute of Mathematics of NAS of Ukraine 2004, Vol. 50, Part 1, 204210 Symmetry Methods Applied to a Mathematical Model
Popovych, Roman
. of Math. and Centre Center for Research Systems, Durban Institute of Technology, PO Box 953, Steve Biko Campus, Durban 4000, Republic of South Africa E-mail: email@example.com School of Mathematical and Statistical Sciences, University of Natal, Durban 4041, Republic of South Africa E-mail: leachp
Workshop: Interferometria com Radar de Abertura Sinttica (InSAR) (Interferometric SAR (InSAR)) Coordenadores: Waldir Renato Paradella (INPE) e Fabio Furlan Gama (INPE)
Workshop: Interferometria com Radar de Abertura Sintética (InSAR) (Interferometric SAR (In enorme disponibilidade de dados de radar de abertura sintética (SAR) de programas espaciais ativos (Terra nestes assuntos. This decade is characterized by a huge amount of Synthetic Aperture Radar (SAR) data
CRECTEALC-CAMPUS BRASIL ANÁLISE COMPARATIVA DE TÉCNICAS DE INFERÊNCIA ESPACIAL PARA IDENTIFICAÇÃO DE UNIDADES DE SUSCETIBILIDADE AOS MOVIMENTOS DE MASSA NA REGIÃO DE SÃO SEBASTIÃO, SÃO PAULO, BRASIL Ciência e Tecnologia Espaciais para América Latina e o Caribe CRECTEALC (Campus Brasil); Ministério da
CBERS-3/4: caractersticas e potencialidades Jos Carlos Neves Epiphanio
Pesquisas Espaciais - INPE Caixa Postal 515 - 12227-010 - São José dos Campos - SP, Brasil epiphanio Unidos, França, Israel, Itália, Japão, Rússia, e outros. O Brasil e a China fazem parte desse grupo. O terrestre. A inserção do Brasil num programa autônomo de imageamento a partir do espaço deu-se com o
Vulnerabilidade socioeconmica ocorrncia de eventos extremos: proposta metodolgica.
- UFSM Av. Roraima, nº 1000 97105-900 Santa Maria RS, Brasil email@example.com 2 Campus Brasil/CRECTEALC Caixa Postal 5021 - 97105-970 - Santa Maria - RS, Brasil email@example.com 3 Instituto Nacional de Pesquisas Espaciais - INPE/CRS Caixa Postal 5021 - 97105-970 - Santa Maria - RS, Brasil tania
Regras para atribuio e renovao de bolsas CAPES e CNPq Art. 1 Os cursos de ps-graduao em nvel de mestrado e doutorado em Computao Aplicada (CAP)
Regras para atribuição e renovação de bolsas CAPES e CNPq Art. 1º Os cursos de pós-graduação em nível de mestrado e doutorado em Computação Aplicada (CAP) do Instituto Nacional de Pesquisas Espaciais a sua proposta de dissertação em até 15 (quinze) meses após o seu ingresso no programa; Art. 3º Não
Application of Three-Dimensional Models for the Teaching of Time Zones. (Breton Title: Aplicação de Modelos Tridimensionais Para o Ensino de Fusos Horários.) Aplicación de Modelos Tridimensionales Para la Enseñanza de Husos Horarios
NASA Astrophysics Data System (ADS)
Azevedo Sobreira, Paulo Henrique
There are several interesting astronomical topics that must be addressed in the High School and Elementary/Middle School in the disciplines of Geography and of Sciences. Among them, the topic of time zones which is one of the most important to understand the correlation of the Earth's rotation and its implications on daily activities of citizens in local scale, regional and global scales which involve problems of time differences. For the teaching of time zones in the lessons of Geography, for example, there are bi-dimensional representations of thematic maps of world time zones, textbooks and atlas. It happens that teachers face some difficulties to permit its students to view three-dimensionally this astronomical phenomenon from the textbooks available in schools. The aim of this paper is to present two proposals with low-cost materials, which allow the preparation of three-dimensional models for the teaching of time zones. Há vários temas astronômicos interessantes que devem ser trabalhados nos Ensinos Médio e Fundamental, nas disciplinas de Geografia e de Ciências. Entre eles, o tema dos fusos horários que é um dos mais importantes para se correlacionar a rotação da Terra e suas implicações nas atividades cotidianas dos cidadãos em escala local, regional e global, que envolvem problemas de diferenças horárias. Para o ensino dos fusos horários nas aulas de Geografia, por exemplo, há representações bidimensionais de mapas temáticos de fusos horários mundiais, nos livros didáticos e nos atlas. Ocorre que os professores enfrentam algumas dificuldades para possibilitar aos seus alunos a visão tridimensional deste fenômeno astronômico, a partir dos materiais didáticos disponíveis nas escolas. O objetivo deste trabalho é apresentar duas propostas para a confecção de materiais de baixo custo, que possibilitem a elaboração de modelos tridimensionais para o ensino dos fusos horários. Hay algunos temas astronómicos interesantes que se deben trabajar en la enseñanza media y básica, en las asignaturas de Geografía y de Ciencias. Entre ellos, el de los husos horarios que es uno de los más importantes para correlacionar la rotación de la Tierra y sus implicaciones en las actividades diarias de los ciudadanos en escala local, regional y global, y en general, cuestiones que implican problemas de las diferencias horarias. Para la enseñanza de los husos horarios en las clases de Geografía, por ejemplo, hay representaciones bidimensionales de los mapas temáticos de husos horarios mundiales, en libros y atlas didácticos. Sin embargo, los profesores se enfrentan con algunas dificultades para hacer posible que sus alumnos tengan una visión tridimensional de este fenómeno astronómico, usando los materiales didácticos disponibles en las escuelas. El objetivo de este trabajo es presentar la construcción de dos propuestas de materiales de bajo costo, que hacen posible la elaboración de modelos tridimensionales para la enseñanza de los husos horarios.
Cloning of Nicotianamine Synthase Genes, Novel Genes Involved in the Biosynthesis of Phytosiderophores
Higuchi, Kyoko; Suzuki, Kazuya; Nakanishi, Hiromi; Yamaguchi, Hirotaka; Nishizawa, Naoko-Kishi; Mori, Satoshi
Nicotianamine synthase (NAS), the key enzyme in the biosynthetic pathway for the mugineic acid family of phytosiderophores, catalyzes the trimerization of S-adenosylmethionine to form one molecule of nicotianamine. We purified NAS protein and isolated the genes nas1, nas2, nas3, nas4, nas5-1, nas5-2, and nas6, which encode NAS and NAS-like proteins from Fe-deficient barley (Hordeum vulgare L. cv Ehimehadaka no. 1) roots. Escherichia coli expressing nas1 showed NAS activity, confirming that this gene encodes a functional NAS. Expression of nas genes as determined by northern-blot analysis was induced by Fe deficiency and was root specific. The NAS genes form a multigene family in the barley and rice genomes. PMID:9952442
Realizacao domestica e escolar de foto e video 3D
Lunazzi, Jose J
English: Industry does not give attention to the small domestic or professional market of digital technologies for 3D images. What was done on the XX century by using photographic film is not know available to the common people, though the facilities are even better. Some technique developed in Brasil twenty years ago and the use of conventional domestic photo or video cameras allows fot making pictures and films at home by using digital conversions for editing, and two-color goggles. The anaglyphic technique, the same NASA employs to show Mars images to the public, is not employed in Brazil yet. We must analize the reasons for that. Portugues: A industria nao tem dado atencao ao mercado domestico ou profissional de pequena escala nas novas tecnologias digitais para imagem 3D. O que foi feito ao longo do seculo XX usando filme fotografico nao esta hoje ao alcance das pessoas, sendo que a facilidade de uso e muito maior. Tecnicas desenvolvidas no Brasil ha mais de vinte anos, e o uso de simples cameras convenc...
M.Cristina Forti,Denise C.Bicudo, Christine Bourotte, ,Valdir de Cicco and Francisco C.S.Arcova
Paris-Sud XI, Université de
Nacional de Pesquisas Espaciais INPE, CP515 S.J.dos Campos, SP/Brasil CEP 12201-970 2 Instituto de Botânica, Av. Miguel Stéfano, 3687, CP 4005 São Paulo SP/Brasil CEP 01061-970 3 NUPEGEL/USP Av Pádua Dias,11; CP 9, Piracicaba SP/Brasil CEP 13418-900 4 Instituto Florestal, R. do Horto, 931 São Paulo SP/Brasil
between clinical signs and hemoglobin color scale as screening methods in the diagnosis of anemia in children Comparação da acurácia do diagnóstico dos sinais clínicos e da escala de cores de hemoglobina como métodos de triagem no diagnóstico da anemia em crianças
Luciana Pedrosa Leal; Mônica M. Osório
Objectives: to compar e the validity and repro- ducibility of clinical signs with the World Health Organization hemoglobin color scale. Methods: Two hundr ed six children in the age range of 6-23 months, at the Instituto Materno Infantil Prof. Fernando Figueira, IMIP, were assessed. Two examiners evaluated the clinical signs and the hemoglobin color scale of each child at the
The influence of joint mobilization on tendinopathy of the biceps brachii and supraspinatus muscles A influência da mobilização articular nas tendinopatias dos músculos bíceps braquial e supra-espinal
Barbosa RI; Goes R; Mazzer N; Fonseca MCR
The most common causes of shoulder pain are related to degeneration of the tendons of the rotator cuff muscles. Objective: To investigate the influence of joint mobilization by means of accessory movements of the shoulder during the early rehabilitation of 14 patients with chronic tendinopathy of the supraspinatus and\\/or biceps brachii muscles. Methods: Two treatment protocols were compared: application of
[Review of] Stali?nas, Darius. Making Russians: Meaning and Practice of Russification in Lithuania and Belarus after 1863. On the Boundary of Two Worlds: Identity, Freedom, and Moral Imagination in the Baltics, 11.
Greenberg, Marc L.
the imperial perspective) from "optimistic" (the NWP can be Russified) to "pessimistic" (the NWP cannot be de-Polonized), revealing a lack of a straightforward top-down, unified approach. Nevertheless, the author concludes that the case of the late Russian... Empire's nationality policy in the NWP is not strikingly different from policies found in other multiethnic states, which vacillate between strengthening minorities and weakening them by supporting their rivals (pp. 299–300). The book reads nearly...
Prisla Ü Calvetti; Erno Harzheim; José Lândio Viana; Cíntia Germany; Mauro C Ramos
Introduction: Bioethics in research with human participants has permitted to address ethical aspects of the health field. STD, HIV and AIDS research is currently amongst the more productive research fields. Objective: To review scientific journals and selected papers in order to evaluate the presence of ethical requirements and description of ethical procedures. Methods: Bibliographic review of an electronic database (SciELO)
Utilização de suplemento alimentar e anabolizante por praticantes de musculação nas academias de Goiânia-GO Use of alimentary supplement and anabolizante for apprentices of muscular activity in the academies of Goiânia-GO
Leandro Rodrigues de Araújo; Jesuíno Andreolo; Maria Sebastiana Silva
Araújo, L. R., Andreolo, J., Silva, M. S. Use of alimentary supplement and anabolizante for apprentices of muscular activity in the academies of Goiânia-GO. Rev. Bras. Ciên. e Mov. 10(3): 13-18, 2002. This is a survey on the use of supplements and anabolic steroid in muscular activity users of fitness club of Goiânia. The study group was constituted by 10%
Strategic Plans for the Future of Solar Physics: a community discussion of the NASA Sun-Earth Connection Program Roadmap and the NAS Decadal Survey of Astronomy and Astrophysics (Solar Astronomy section)
K. Schrijver; M. Knoelker
The NASA Sun-Earth Connections Program is currently revising its Roadmap, the long-range plan for science goals, technology development, and missions between 2000 and 2040. From the interior dynamics of the Sun, to the interactions of plasma, fields, and radiation in the photosphere and solar atmosphere, to the heating and structure of the corona, to the acceleration, structure, and evolution of
SISTeMAS De INFoRMACIÓN: INTeRNeT, ACCeSo Y USo PoR TRABAJADoReS De SALUD Y PeRSoNAS VIVIeNDo CoN VIH\\/SIDA
Patricia J. García; Patricia Caballero Ñ; Víctor Suárez M; Luis Fuentes-Tafur
ReSUMeN El Instituto Nacional de Salud desarrolló NETLAB, un sistema de información basado en la Web que aumenta la disponibilidad de los resultados de laboratorio a los trabajadores de salud y a los pacientes viviendo con VIH\\/SIDA (PVVS). Para asegurar su efectividad se requiere conocer aspectos como recursos y acceso a Internet. Objetivos: Describir las características del acceso a Internet
ILEGIBILIDADE E AUSÊNCIA DE INFORMAÇÃO NAS PRESCRIÇÕES MÉDICAS: FATORES DE RISCO RELACIONADOS A ERROS DE MEDICAÇÃO Illegibility and lack of information in medical prescriptions: risk factors related to medication errors
Geysa Aguiar; Lourival Alves da Silva; Marco Antônio Magalhães
RESUMO Os erros na medicação podem acarretar sérias conseqüências aos pacientes, profissionais e instituições de saúde. Estes resultam de múltiplas causas, dentre elas a ilegibilidade e falta de informações das prescrições. Realizou-se um estudo de prescrições médicas com o objetivo de analisar a freqüência de riscos relacionados a erros de medicação. O estudo teve caráter quantitativo, do tipo descritivo e
Geoprocessamento aplicado ao mapeamento dos impactos socioambientais decorrentes das formas de uso da terra nas Áreas de Preservação Permanente (APPs) da Represa de Salto Grande no município de Americana (SP)
Joyce Rodrigues da Cruz
The Dam of Salto Grande, occupying an area of 10.5 km2, is located in the hydrographical basin of the Atibaia River, important tributary of the Piracicaba River, in the State of São Paulo. It takes care of, in the present time, to the inhabitants of the cities of Americana, Paulínia and Nova Odessa, that also use the source for activities
A Pos-Graduacao Nas Ciencias Humanas e o Paradigma da Medicina: A Era da Especializacao. (Post-Graduation in the Human Sciences and the Paradigm of Medicine: The Era of Specialization.)
ERIC Educational Resources Information Center
Costa, Celio Juvenal
Reflects on the current tendency in Brazilian higher education for greater and greater specialization, particularly in human sciences and in medicine. Calls for less specialization and a more historic and general preparation, especially in teacher education. (BT)
The National Academies | Science in the Headlines | New Research Mim... http://www.nas.edu/headlines/20060124.html 1 of 1 1/27/2006 8:03 AM
-matter physics. Nuclear Physics: The Core of Matter, The Fuel of Stars examines research goals for physicists density and temperature?" Nuclear Physics: The Core of Matter, The Fuel of Stars (1999) Frontiers in High -- for independent, objective advice on issues that affect people's lives worldwide. The National Academies Office
A comparison of PETSc library and HPF implementations of an archetypal PDS computation 1 This work was supported by the National Aeronautics and Space Administration under NASA Contract Nos NAS1-97046 and NAS1-19480, whilst the authors were in residence at ICASE MS 403, NASA Langley Research Center, Hampton, VA 23681-0001. Access to the NASA SP2s was provided under the NASA High Performance Computing and Communication Program. 1
M. Ethesham Hayder; David E. Keyes; Piyush Mehrotra
Two paradigms for distributed-memory parallel computation that free the application programmer from the details of message passing are compared for an archetypal structured scientific computation—a nonlinear, structured-grid partial differential equation boundary value problem—using the same algorithm on the same hardware. Both paradigms, parallel libraries represented by Argonne's PETSc, and parallel languages represented by the Portland Group's HPF, are found to
National Research Council NUCLEAR SCIENCE SERIES
.00 Radium, NAS.NS.3C)57 [lg64j ,$7,75 Rare Earths---Scandium, Yttrium, and Actinium, NAS-NS-3020 [1961] , $9.25 Rare Gases, NAS-NS-3025 [ 19601, $4.50 Rherrlum, NAS-NS-3028 [ 1961] , $4.00 Rhodium, NAS-NS-300B (Rev, NAS-NS-3105 [1961] ,$6.00 Liquid-Liquid Extraction with High- Molecular-Weight Amines, NAS-NS-3101
Determination of N-acetylserotonin and Melatonin Activities in the Pineal Gland, Retina, Harderian Gland, Brain and Serum of Rats and Chickens
S. F. Pang; G. M. Brown; L. J. Grota; J. W. Chambers; R. L. Rodman
An N-acetylserotonin\\/melatonin radioimmunoassay (NAS\\/Mel RIA) and a Mel RIA were developed to measure NAS and Mel contents in tissues of rats and chickens. Anti-NAS and anti-Mel sera were produced by immunization of rabbits with NAS-M-bovine serum albumin (BSA) and Mel-M-BSA, respectively. Anti-NAS serum used in the NAS\\/Mel RIA reacts equally well with NAS and Mel, while anti-Mel serum used in
Nitrogen Oxyanion-dependent Dissociation of a Two-component Complex That Regulates Bacterial Nitrate Assimilation*
Luque-Almagro, Victor M.; Lyall, Verity J.; Ferguson, Stuart J.; Roldán, M. Dolores; Richardson, David J.; Gates, Andrew J.
Nitrogen is an essential nutrient for growth and is readily available to microbes in many environments in the form of ammonium and nitrate. Both ions are of environmental significance due to sustained use of inorganic fertilizers on agricultural soils. Diverse species of bacteria that have an assimilatory nitrate/nitrite reductase system (NAS) can use nitrate or nitrite as the sole nitrogen source for growth when ammonium is limited. In Paracoccus denitrificans, the pathway-specific two-component regulator for NAS expression is encoded by the nasT and nasS genes. Here, we show that the putative RNA-binding protein NasT is a positive regulator essential for expression of the nas gene cluster (i.e. nasABGHC). By contrast, a nitrogen oxyanion-binding sensor (NasS) is required for nitrate/nitrite-responsive control of nas gene expression. The NasS and NasT proteins co-purify as a stable heterotetrameric regulatory complex, NasS-NasT. This protein-protein interaction is sensitive to nitrate and nitrite, which cause dissociation of the NasS-NasT complex into monomeric NasS and an oligomeric form of NasT. NasT has been shown to bind the leader RNA for nasA. Thus, upon liberation from the complex, the positive regulator NasT is free to up-regulate nas gene expression. PMID:24005668
Nitrogen oxyanion-dependent dissociation of a two-component complex that regulates bacterial nitrate assimilation.
Luque-Almagro, Victor M; Lyall, Verity J; Ferguson, Stuart J; Roldán, M Dolores; Richardson, David J; Gates, Andrew J
Nitrogen is an essential nutrient for growth and is readily available to microbes in many environments in the form of ammonium and nitrate. Both ions are of environmental significance due to sustained use of inorganic fertilizers on agricultural soils. Diverse species of bacteria that have an assimilatory nitrate/nitrite reductase system (NAS) can use nitrate or nitrite as the sole nitrogen source for growth when ammonium is limited. In Paracoccus denitrificans, the pathway-specific two-component regulator for NAS expression is encoded by the nasT and nasS genes. Here, we show that the putative RNA-binding protein NasT is a positive regulator essential for expression of the nas gene cluster (i.e. nasABGHC). By contrast, a nitrogen oxyanion-binding sensor (NasS) is required for nitrate/nitrite-responsive control of nas gene expression. The NasS and NasT proteins co-purify as a stable heterotetrameric regulatory complex, NasS-NasT. This protein-protein interaction is sensitive to nitrate and nitrite, which cause dissociation of the NasS-NasT complex into monomeric NasS and an oligomeric form of NasT. NasT has been shown to bind the leader RNA for nasA. Thus, upon liberation from the complex, the positive regulator NasT is free to up-regulate nas gene expression. PMID:24005668
ACADEMIC COURSES SUBSTITUTION COURSES Subject # Course Title CR Grade Subject # Course Title CR Grade
Dyer, Bill
: NAS 201 American Indians in Montana 3 Native American Studies Requirements - Choose one (1) of the following: NAS 320 American Indian Religions 3 NAS 340 American Indian Literature 3 NAS 405 Gender Issues in Nat Am Studies 3 NAS 430 American Indian Education 3 SOCIAL STUDIES BROADFIELD Catalog 2008-2010 GID
Determination and characterization of oxy-naphthenic acids in oilfield wastewater.
Wang, Beili; Wan, Yi; Gao, Yingxin; Yang, Min; Hu, Jianying
Oxy-naphthenic acids (oxy-NAs) are one of the major components of NA mixtures in wastewaters from petroleum industries. The limited available data indicated that oxy-NAs were considered as a potential marker for the degradation of NAs, and some oxy-NAs exhibited endocrine disrupting activities. However, the lack of information on the structures and occurrences of oxy-NAs in oilfield wastewaters limited the interpretations of the biotransformation pathways of NAs and structure-specific toxicity. A sensitive method for simultaneous determination of oxy-NAs together with NAs was developed by combining MAX extraction column and UPLC-ESI(-)-QTOF-MS. The 2000-fold SPE preconcentration step was highly specific for acids and the prewash solvent greatly reduced matrix effects in the UPLC-ESI(-)-QTOF-MS analysis, resulting in an increase in sensitivity down to detection limits in the ng/L range. To provide structural information within each oxy-NA isomer class, a new method was developed by derivatizing oxy-NAs with dansyl chloride by UPLC-ESI(+)-QTOF-MS. The molecular ion dansyl derivatives from the corresponding oxy-NAs and characteristic fragmentation ions, not detected before derivatization, were observed in the extracts of oilfield wastewater, providing evidence that O3-NAs and O4-NAs were mainly composed of OH-NAs and (OH)2-NAs, respectively. Semiquantification of oxy-NAs and NAs in various oilfield wastewaters revealed NAs, O3-NAs, and O4-NAs present at concentrations of 187-397, 44-146, and 40-108 ?g/L, respectively. Significantly different profiles of NA mixtures were observed in petroleum refinery wastewater and oil sands extraction water, but the profile of oxy-NAs was similar to NAs in different wastewaters suggesting the existence of biotransformation between NAs and oxy-NAs in the environment, and hydroxylation could be one of the major biotransformation pathways of NAs. PMID:23859600
COSPAR's programme of capacity-building workshops
NASA Astrophysics Data System (ADS)
Willmore, Peter
For some time, COSPAR has been planning a programme of capacity-building workshops to be held in developing countries, and the first of these was held at Institute Nacional de Pesquisas Espaciais (INPE), São José dos Campos, Brazil from 4th to 13th December 2001. The next two will be held in Udaipur, India and in Beijing, China, respectively, during 2003. The workshops are innovative in character, and their objectives and their concepts will be described, as well as the experience gained from the first workshop in Brazil.
Paraná, Universidade Federal do
COMPRAS, CONTRATOS E PATRIMÔNIO PREGÃO ELETRÔNICO Nº 118/2012 =SRP VALIDADE 07/11/12 a 06 PARANÁ PRÓ-REITORIA DE ADMINISTRAÇÃO DSG/CENTRAL DE COMPRAS, CONTRATOS E PATRIMÔNIO confeccionado com resposta (estabilização) menor que 3 s escala maior, menor que 15s escala menor; Temperatura ambiente: 5
dos Santos, C.A.
UNIVERSIDADE FEDERAL DO RIO GRANDE DO SUL PROGRAMA DE PÓSGRADUAÇÃO EM MICROELETRÔNICA Grade de SEXTA 8:30 10:30 MIC02 CONCEPÇÃO DE CIRCUITOS EM ALTA ESCALA (VLSI) (Prof. Sergio Bampi) (II) MIC02 CONCEPÇÃO DE CIRCUITOS EM ALTA ESCALA (VLSI) (Prof. Sergio Bampi) (II) MIC69
Long-time numerical computation of wave-type solutions driven by moving sources ? ? This work was supported by the National Aeronautics and Space Administration under NASA Contract No. NAS1-97046, and by Director's Discretionary Fund, while the first and second authors were in residence at ICASE, NASA Langley Research Center, Hampton, VA, USA
V. S. Ryaben'kii; S. V. Tsynkov; V. I. Turchaninov
We propose a methodology for calculating the solution of an initial-value problem for the three-dimensional wave equation over arbitrarily long time intervals. The solution is driven by moving sources that are compactly supported in space for any particular moment of time; the extent of the support is assumed bounded for all times. By a simple change of variables the aforementioned
Parsec-scale radio structures in Quasars
NASA Astrophysics Data System (ADS)
Coldwell, G.; Paragi, Z.; Gurvits, L.
Very Long Baseline Interferometry (VLBI) con su nueva extensión para el radio telescopio orbital, VSOP/HALCA, ofrece una incomparable resolución angular alcanzando escalas de milisegundos y submilisegundos de arco a longitudes de onda de centímetros. En este trabajo presentamos observaciones y análisis de estructuras en radio, en escalas de parsec, para 3 radio fuentes extragalácticas de la muestra de VSOP Survey y 1 quasar, 1442+101, del proyecto `VSOP High Redshift'.
José Alberto Martínez González
La presente investigación tiene como objetivo determinar la relación existente entre la inteligencia emocional (competencia emocional auto-percibida) y el rendimiento académico de 287 estudiantes universitarios de un centro que está plenamente adaptado al Espacio Europeo de Educación Superior (EEES). Se han aplicado la escala TMMS-24 y las escalas TIE-76 y TIE-34, diseñadas ad hoc. El rendimiento académico de los alumnos
75 FR 19212 - Modification of Class E Airspace; Oxnard, CA
Federal Register 2010, 2011, 2012, 2013, 2014
...Modification of Class E Airspace; Oxnard, CA AGENCY: Federal Aviation Administration...Mugu Naval Air Station (NAS), Oxnard, CA. Additional controlled airspace is necessary...coordinates of Point Mugu NAS, Oxnard, CA. DATES: Effective Date: 0901 UTC,...
file:///Users/salvina/Desktop/Jan%203/ionline18Jan.htm[12/01/24 15:21:06] ARTIGO INTERNET
Instituto de Sistemas e Robotica
como a redução do número de feriados, dos dias de férias e das pontes "terão que ter impacto" na trabalho em meia hora diária. Em troca, há mudanças nas férias, nos feriados, nas pontes e na criação de um
file:///Users/salvina/Desktop/Jan%203/economico18Jan.htm[12/01/24 15:20:53] ARTIGO INTERNET
Instituto de Sistemas e Robotica
do número de feriados, dos dias de férias e das pontes "terão que ter impacto" na competitividade do troca, há mudanças nas férias, nos feriados, nas pontes e na criação de um banco de horas individual
75 FR 62536 - Notice of Public Information Collection(s) Being Reviewed by the Federal Communications...
Federal Register 2010, 2011, 2012, 2013, 2014
...National Airspace System (NAS). This will...NAS, which shares system components with...characteristics, rated output power, emission type...Section 64.901, Allocation of Cost and Section...Management Information System (ARMIS). [[Page 62538
Identification of Communication and Coordination Issues in the U. S. Air Traffic Control System
Davison, Hayley
Today's air traffic control system is approaching the point of saturation, as evidenced by increasing delays across the National Airspace System (NAS). There exists an opportunity to enhance NAS efficiency and reduce ...
76 FR 44579 - Notice of Availability of Environmental Assessment for Strike Fighter Realignment at Naval Air...
Federal Register 2010, 2011, 2012, 2013, 2014
...of strike fighter assets at Naval Air Station (NAS) Lemoore...Realignment EA Project Manager; Naval Facilities Engineering Command...of NAS Lemoore's existing training squadron, will result in a...Realignment EA Project Manager; Naval Facilities Engineering...
36 CFR 1234.30 - How does an agency request authority to establish or relocate records storage facilities?
Code of Federal Regulations, 2013 CFR
...Forests, and Public Property NATIONAL ARCHIVES AND RECORDS ADMINISTRATION RECORDS...Management Division (NAS), National Archives and Records Administration, 8601 Adelphi...Management Division (NAS), National Archives and Records Administration, 8601...
36 CFR 1234.10 - What are the facility requirements for all records storage facilities?
Code of Federal Regulations, 2012 CFR
...Forests, and Public Property NATIONAL ARCHIVES AND RECORDS ADMINISTRATION RECORDS...Management Division (NAS), National Archives and Records Administration, 8601 Adelphi...Management Division (NAS), National Archives and Records Administration, 8601...
Engine Design for LIFE Presentation to
") * Courtesy Lew Shoemaker, Special Metals Corporation Latkowski -- NAS/NAE, January 2011 · 6 m radius chamber a thermal/corrosion barrier between Li and steel structure. Latkowski -- NAS/NAE, January 2011 First wall
UPMC Direction des ressources humaines 4, place Jussieu 75252 Paris cedex 05
et Fiber Channel) pour SAN/NAS - Administration de serveurs linux (Redhat) - Gestion des comptes'architecture SAN/NAS, ainsi que des systèmes Unix/Linux/Windows et réseaux Fibre Channel - Connaissance approfondie
NASA Technical Reports Server (NTRS)
Debarrosaguirre, J. L.
The current status of the Brazilian LANDSAT facilities operated by Instituto de Pesquisas Espaciais (INPE) and the results achieved during the period from October 1, 1984 to August 31, 1985 are presented. INPE's Receiving Station at Cuiaba, MT, operates normally the two tracking and receiving systems it has installed, the old one (1973) for Band S and the new one (February 1983) for dual S- and X-band. Both MSS and TM recording capabilities are functional. Support to the NASA Backup Plan for MSS data also remains active. Routine recordings are being made for LANDSAT-5 only, for both MSS and TM. Originally, MSS was recorded over the full acquisition range. However, since December, 1984, due to further reduction of operational expenses, both instruments are being recorded over Brazilian territory only.
Analysis of upstream region of nicotianamine synthase gene from Arabidopsis thaliana: presence of putative ERE-like sequence.
Suzuki, K; Nakanishi, H; Nishizawa, N K; Mori, S
Nicotianamine (NA) is present in all plants so far examined, and is thought to chelate transition metal ions. Previously, we isolated three nicotianamine synthase (NAS) genes of Arabidopsis thaliana (AtNAS1, 2, and 3) and showed that each NAS gene is differentially expressed. Deletion analysis of the 5' flanking region of AtNAS3 found a putative ethylene-responsive sequence, ATTTTCAAA. PMID:11826981
Estimating naphthenic acids concentrations in laboratory-exposed fish and in fish from the wild
Rozlyn F. Young; Wendy V. Wismer; Phillip M. Fedorak
Naphthenic acids (NAs) are the most water-soluble organic components found in the Athabasca oil sands in Alberta, Canada, and these acids are released into aqueous tailing waters as a result of bitumen extraction. Although the toxicity of NAs to fish is well known, there has been no method available to estimate NAs concentrations in fish. This paper describes a newly
Correlation between the corrosivity of naphthenic acids and their chemical structures
Ding-Rong Qu; Yu-Gui Zheng; Xiu Jiang; Wei Ke
Purpose – The objective of the present work was to study the influence of chemical compositions of five naphthenic acids (NAs) extracted from Liaohe crude oil on their corrosivity. Design\\/methodology\\/approach – Fourier-transform infrared spectrometry and electron impact mass spectrometry were used to characterize the chemical structures and compositions if five NAs. The corrosivities of the NAs were assessed by stagnant
Naphthenic acid biodegradation by the unicellular alga Dunaliella tertiolecta
Dean M. Quesnel; Iyswarya M. Bhaskar; Lisa M. Gieg; Gordon Chua
Naphthenic acids (NAs) are a major contributor to toxicity in tailings waste generated from bitumen production in the Athabasca Oil Sands region. While investigations have shown that bacteria can biodegrade NAs and reduce tailings toxicity, the potential of algae to biodegrade NAs and the biochemical mechanisms involved remain poorly understood. Here, we discovered that the marine alga Dunaliella tertiolecta is
The nature of Neptune's increasing brightness: evidence for a seasonal response ? ? Based on observations made with the NASA\\/ESA Hubble Space Telescope and on observations obtained from the data archive at the Space Telescope Science Institute (STScI), which is operated by the Association of Universities for Research in Astronomy, Inc. under NASA Contract NAS 5-26555. Research supported by grants from STScI and NASA's Planetary Atmospheres Program
L. A. Sromovsky; P. M. Fry; S. S. Limaye; K. H. Bainesb
Hubble Space Telescope (HST) observations in August 2002 show that Neptune's disk-averaged reflectivity increased significantly since 1996, by 3.2 ± 0.3% at 467 nm, 5.6 ± 0.6% at 673 nm, and 40 ± 4% in the 850–1000 nm band, which mainly results from dramatic brightness increases in restricted latitude bands. When 467-nm HST observations from 1994 to 2002 are added
Time-Space Trade-Offs for Longest Common Extensions
Lonardi, Stefano
4 sna 6 s a 1 bananas 3 nas 5 s na 7 s 12 / 56 #12;Two Simple Solutions #1: Store nothing T = b a n nas 4 sna 6 s a 1 bananas 3 nas 5 s na 7 s LCE(i, j) = |NCA(i, j)| = 3 13 / 56 #12;Two Simple: Store the suffix tree NCA(2, 4) 2 nas 4 sna 6 s a 1 bananas 3 nas 5 s na 7 s Time: O(1) Space: O(n) LCE
Digestion of Nucleic Acids Starts in the Stomach
Liu, Yu; Zhang, Yanfang; Dong, Ping; An, Ran; Xue, Changhu; Ge, Yinlin; Wei, Liangzhou; Liang, Xingguo
The ingestion of nucleic acids (NAs) as a nutritional supplement or in genetically modified food has attracted the attention of researchers in recent years. Discussions over the fate of NAs led us to study their digestion in the stomach. Interestingly, we found that NAs are digested efficiently by human gastric juice. By performing digests with commercial, recombinant and mutant pepsin, a protein-specific enzyme, we learned that the digestion of NAs could be attributed to pepsin rather than to the acidity of the stomach. Further study showed that pepsin cleaved NAs in a moderately site-specific manner to yield 3?-phosphorylated fragments and the active site to digest NAs is probably the same as that used to digest protein. Our results rectify the misunderstandings that the digestion of NAs in the gastric tract begins in the intestine and that pepsin can only digest protein, shedding new light on NA metabolism and pepsin enzymology. PMID:26168909
The nursing assistants' communication style and the behavioral symptoms of dementia in Korean-American nursing home residents.
Kim, Haesook; Woods, Diana Lynn; Mentes, Janet C; Martin, Jennifer L; Moon, Ailee; Phillips, Linda R
Few studies examined the association between communication style and behavioral symptoms of dementia (BSD). The communication style of Nursing Assistants' (NAs), whose ethnic background is different from the residents, may contribute to BSD. The purpose of this study was to explore the relationship between non-Korean NAs' communication style and BSD in Korean-American (KA) nursing home residents with dementia. Twenty eight NAs and 20 KA residents were recruited from an ethno-specific nursing home. Research assistants observed and recorded NAs' communication style and residents' behavior simultaneously during routine care for 3 days. This study shows a trend that NAs' dementia and culturally appropriate communication style influenced the decreased behavioral symptoms. This finding suggests the need for training for NAs in dementia and culturally appropriate communication. PMID:24702713
shrI mahAgaNapatim bhajEham Ragam: Atana (29th Mela Shankarabharanam Janyam)
Kalyanaraman, Shivkumar
AgaNapatim bhajEham shivAtmajam SaNmukhAgrajam Anupallavi: shrta gaNasEvitam vighna nAshakam shIgra vara prasAda d") in our lives. He gives ("dAyakam") boons ("vara") and blessings ("prasAda") very quickly ("shIgra"). C1: shrta gaNasEvitam vighna nAshakam shIgra vara prasAda dAyakam Sahityam: shrta gaNasEvitam vighna n
A derivatisation and liquid chromatography/electrospray ionisation multistage mass spectrometry method for the characterisation of naphthenic acids.
Smith, B E; Rowland, S J
Naphthenic acids (NAs) are partially uncharacterised complex mixtures of carboxylic acids, resulting from the microbial oxidation of petroleum hydrocarbons. They are associated with the fouling of pipelines and process equipment in oil production and with corrosion in oil refineries. As by-products of the rapidly expanding oil (tar) sands industries, NAs are also pollutants and have proved to be toxic to a range of organisms. They also have important beneficial uses as fungicides, tyre additives and, paradoxically, also in the manufacture of corrosion inhibitors. These features make the characterisation of NAs an important goal for analytical chemists. Here we describe the synthesis of amide derivatives of NAs for characterisation by liquid chromatography/electrospray ionisation multistage mass spectrometry (LC/ESI-MS(n)). The method was applied to commercially available carboxylic acids, novel synthetic NAs, commercial NAs refined from crude oils, crude oil NAs and Athabasca oil sands NAs. In addition to confirming the number of alicyclic rings and length of alkyl side chain substituents (confirming information from existing methods), the MS(n) results provided further structural information. Most important of these was the finding that bi- to polycyclic acids containing ethanoate side chains, in addition to alkyl substituents, were widespread amongst the oil and oil sands NAs. The latter NAs are known end members of the beta-oxidation of NAs with even carbon number alkanoate chains. Since such NA mixtures are toxic, they should be targets for bioremediation. Bioremediation of NAs can also be monitored better by application of the methods described herein. PMID:18988206
Commercial naphthenic acids and the organic fraction of oil sands process water downregulate pro-inflammatory gene expression and macrophage antimicrobial responses
Erick Garcia-Garcia; Jonathan Pun; Leonidas A. Perez-Estrada; Mohamed Gamal-El Din; Daniel W. Smith; Jonathan W. Martin; Miodrag Belosevic
This is the first report showing that the organic fraction of oil sands process water (OSPW-OF), and commercial naphthenic acids (C-NAs), cause immunotoxicity. The exposure of mouse bone marrow-derived macrophages (BMDM) to different amounts of C-NAs or OSPW-OF, did not affect cell viability in vitro. We examined whether exposure of BMDM to C-NAs or OSPW-OF affected various antimicrobial responses of
Linhardt, Robert J.
, geomicrobiology, and microbial ecology in extreme ecosystems; astrobiology and planetary habitability Frank spear, tectonics Bruce Watson nas, institute Professor Transport properties, numerical modeling
[Alcohol, and tobacco consumption and sports practice in Mexican and Spanish university students and the association between quality of life and health and sensation seeking].
Latorre-Román, Pedro Ángel; Gallego-Rodríguez, María; Mejía-Meza, José Armando; García-Pinillos, Felipe
Objetivo: Analizar el consumo de alcohol y tabaco y la práctica deportiva de universitarios mexicanos y españoles y su relación con la calidad de vida relacionada con la salud y la búsqueda de sensaciones. Material y métodos: Han participado 309 universitarios, 154 españoles y 155 mexicanos. Se ha empleado la escala de búsqueda de sensaciones forma V (Sensation Seeking Scale [SSS-V]), el Healthy Survey Short-Form 36 (SF-36) y un cuestionario de hábitos de vida realizado ad hoc. Resultados: Los estudiantes mexicanos presentan menor frecuencia de consumo de tabaco y alcohol y de borracheras que los españoles, así como mayor frecuencia de práctica deportiva; los estudiantes españoles perciben puntuaciones superiores en la escala SF-36. La desinhibición (DES) es un factor de riesgo para el consumo de alcohol y la inactividad física, mientras que la escala total SSS-V lo es para el consumo de tabaco. Conclusiones: El consumo diario de alcohol y tabaco y la inactividad física en universitarios de España y de Méjico son bajos. La escala total SSS-V es un predictor del consumo de tabaco y la dimensión DES del consumo de alcohol y la inactividad física. PMID:25946531
Cimpor regista patente que reduz emisses de CO2 at 25%
Instituto de Sistemas e Robotica
experimentada à es- calalaboratorial, irá agora ser apli- cada a nível industrial", disse ao Ne- gócios, Paulo- mento. A solução agora patentea- da, aplicada à escala industrial, vai permitir uma redução das emis- térias-primas com menos calcário, é precisamente o que a patente agora registada visa Relativamen- te aos
Paraná, Universidade Federal do
desse edital, os candidatos abaixo relacionados estão convocados a participarem da entrevista, no dia 09/02/2012, na sala 914, do Ed. Dom Pedro I da Reitoria da UFPR, segundo a escala a seguir: Ordem Nome Horário 1 ADRIANA WAGNITZ PACH 10h00 8 DANIELLE RODRIGUES DA SILVA 10h20 9 FLAVIA BOZZA MARTINS 10h40 10 RICARDO
Relative abundance of amphibians in forest canopy gaps of natural origin vs. timber harvest origin
C. Stronjny; M. L. Hunter
Los claros a pequeña escala producidos en el dosel forestal por la industria maderera pueden conservar una estructura del hábitat apropiada para mantener la abundancia de anfibios. Utilizamos trampas con vallas de intercepción para medir la abundancia relativa de anfibios en 44 claros en que la madera había sido cortada, 19 claros naturales producidos por la caída de los árboles,
Carlos A. Moreno; Pedro S. Rubilar
RESUMEN Se definen las escalas de tiempo para una población marina como un ciclo anual o corto plazo, tiempo generacional o mediano plazo y duración del ciclo de vida o longevidad como largo plazo. De acuerdo con ellas, a nivel del instrumento de manejo llamado Reserva Marina, la pregunta ¿si la acción de conservación de crear una Reserva Marina tiene
Se busca una raíz unitaria: evidencia para Chile
Rómulo Chumacero Escudero
Este documento presenta evidencia contundente en contra de la hipótesis nula de que series tales como el IMACEC, el consumo o el PIB chilenos presentan una raíz unitaria. Esta evidencia se apoya en resultados derivados en Chumacero (2000) que muestran que en caso que alguna de estas variables de escala sea estacionaria en diferencia, los retornos de activos disponibles para
Correspondencias estructurales y semánticas entre El gesticulador y Corona de sombra
Scarano, Laura Rosana
justicia, donación de la vida y verdad (a pesar del paradojal enmas caramiento y las dualidades de identidad). Sin embargo, a pesar de estas convenciones iluminadoras que lo llevan a reinterpretar la historia a la luz de una escala axiológica y ética...
Marina Veloso de Melo; Marconi Freitas da Costa; Emanuel Ferreira Leite
RESUMO: Este estudo tem como objetivo geral identificar se os produtos fabricados com impactos reduzidos sobre o meio-ambiente influenciam no processo de decisão de compra do consumidor em Recife. Através da aplicação de 100 questionários padronizados nos dois maiores shoppings da cidade, os quais constaram de questões de múltipla escolha e escalas de Likert , observou-se que os consumidores têm
dos Santos, C.A.
PROGRAMA DE PÓS-GRADUAÇÃO EM MICROELETRÔNICA PGMICRO UNIVERSIDADE FEDERAL DO RIO GRANDE DO SUL-Graduação em Microeletrônica, em reunião de 13 de agosto de 2008, Resolve - A aprovação na disciplina MIC59 obrigatória MIC02 Concepção de Circuitos em Alta Escala (VLSI), 4 créditos. Prof. Henri Ivanov Boudinov
modelos con varias escalas de tiempo. La agregación aproximada de sistemas consiste en definir a partir deAPLICACIONES A LA ECOLOGÍA DE LA AGREGACIÓN APROXIMADA DE VARIABLES EN SISTEMAS DINÁMICOS DISCRETOS de variables permiten reducir el número de variables de un sistema dinámico, dando lugar a otro
García, Oscar
Modelos de un mismo sistema pueden diferir mucho en su escala, nivel de detalle, o más preci- samente en, Sistemas complejos, Gestión forestal INTRODUCCIÓN Los modelos de crecimiento son útiles como instrumentosDIMENSIONALIDAD EN LOS MODELOS DE CRECIMIENTO Oscar García University of Northern British Columbia
Un modelo descriptivo del sistema reproductor hembra del coipo (Myocastor coypus) I: el ovario (A descriptive model of the female reproductive system of coypu (Myocastor coypus) I: the
R. Argentina
El coipo (Myocastor coypus) es un roedor de amplia utilización como especie peletera a escala mundial. Los ambientes naturales ocupados por el coipo son los acuático-continentales, si bien la especie ha demostrado gran adaptabilidad a diferentes ambientes y regiones geográficas. A partir de su liberación accidental de granjas de cría, se localizan poblaciones naturalizadas en Inglaterra, EEUU, países del Este
Estudio del NCI revela que la obesidad extrema puede acortar la esperanza de vida hasta en 14 años
Los adultos con obesidad extrema tienen un mayor riesgo de morir a una edad más joven debido al cáncer y a muchas otras causas entre ellas, enfermedades cardíacas, accidentes cerebrovasculares, diabetes y enfermedades del hígado y los riñones, según los resultados de un análisis de datos de 20 estudios a gran escala realizados en personas de tres países.
Inconvenient Tales of Dinosaurs D. Richstone
Maryland at College Park, University of
with BH fueling Burkert & Silk 2001, Escala · Mass reservoir is · BH accretion rate is · Star formation;Compare inferred demographics to quasars. · Dispersion-based demographics predict fewer high mass bh than luminosity-based demographics. · Dispersion-based estimates of the numbers of the most massive BH are barely
Translation, Adaptation, and Validation of the Stanford Hypnotic Clinical Scale in Puerto Rico
Yazmín Deynes-Exclusa; Sean K. Sayers-Montalvo; Alfonso Martínez-Taboas
The only hypnotizability scale that has been translated and validated for the Puerto Rican population is the Barber Suggestibility Scale (BSS). In this article, the Stanford Hypnotic Clinical Scale (SHCS) was translated and validated for this population. The translated SHCS ("Escala Stanford de Hipnosis Clínica" [ESHC]) was administered individually to 100 Puerto Rican college students. There were no significant differences
Creencias y actitudes hacia la hipnosis de los psicólogos españoles
M. Elena Mendoza; Antonio Capafons; Begoña Espejo; Doris Montalvo
El objetivo de este estudio es analizar las creencias y actitudes hacia la hipnosis de los colegia- dos para informar al Consejo General de Colegios Oficiales de Psicólogos de las necesidades de formación sobre hipnosis, así como analizar las respuestas en función de los Colegios de los par- ticipantes. Para ello se aplicó la Escala de Valencia de Actitudes y
Caracterización reológica de los lodos de un digestor anaeróbico con alta concentración de sólidos desde el punto de vista de su escalamiento
A. F. González; E. Giraldo
RESUMEN: Debido a las limitaciones de transferencia de masa, calor y momento que puede presentar un di- gestor de lodos anaeróbico de alta concentración de sólidos a gran escala se caracterizó reológicamente el lo- do de un digestor para conocer su comportamiento a diferentes de temperaturas y concentración de sólidos. En general los lodos obedecen el modelo de Herschel-Bulkley donde
Calculo III, aug-dic 2011. Tarea num. 4
Bor, Gil
vector general v = (v1, v2). Nota: al hacer inciso 7 (calcular y dibujar la gradiente) tienes que dibujar vectores. Al dibujar las flechas, tienes que cambiar la escala, para que no se encimen las flechas. Es decir, el campo que vas a dibujar en el plano no es f, sino c f, para un c > 0 bastante peque
Evaluación diferencial de los programas de acogimiento residencial para menores
Eduardo Martín; Teresa Rodríguez; Ángela Torbay
En este trabajo se realiza una evaluación de los programas de acogimiento residencial para menores desde la perspectiva de evaluación de resultados. Tomando dos medidas separadas nueve meses en el tiempo a un total de 175 menores, y utilizando la escala de observación mensual de objetivos del Pro- yecto Educativo Individualizado, encontramos que, en la mayoría de las dimensiones analizadas,
2354 -XIV Encuentro de Latinoamericanistas Espaoles DELIBERACIN E INTEGRACIN
Paris-Sud XI, Université de
DESARROLLO SOSTENIBLE) Antonio García Allut Universidad de A Coruña España Javier Seijo Villamizar USC España Pesqueras por el Desarrollo Sostenible). De ahí que el papel de este trabajo trate de dar respuesta a si América latina, desde un proyecto de cooperación al desarrollo en pesca artesanal o de pequeña escala y
Caracterización y selección del lugar de nidificación de la grulla cubana (Grus canadensis nesiotes) en los herbazales del Refugio de Fauna El Venero, Cuba
Y. Ferrer Sánchez; D. Denis Ávila; I. Ruiz Companioni
Grus canadensis nesiotes es una subespecie endémica y amenazada de grulla cuyas poblaciones están asociadas a humedales de agua dulce. En este trabajo se caracterizó su lugar de nidificación y se determinó su selección a tres escalas espaciales en los herbazales del Refugio de Fauna El Venero, Cuba, durante los años 2005–2007. Se monitorizaron 26 nidos hasta la eclosión. También
Descoberta e Monitoramento de Recursos em Redes de Computadores usando Agentes Móveis
Inácio Dutra; Joaquim Celestino
Resumo. Com a expansão e proliferação de novas tecnologias de rede e a demanda d e novos serviços vem tornando cada vez mais difícil administrar redes em larga escala sem um sistema d e gerenciamento inteligente, automatizado. Descobrir e manter um mapeamento da topologia de uma rede são essenciais para se ter uma administração efetiva. Neste artigo apresentamos uma a
920 Rev. Colomb. Psiquiat., vol. 41 / No. 4 / 2012 Cartasa l e d i t o r
Hammerton, James
diagnósticas en trastornos del comportamiento alimentario (TCA) Sergio Andrés Ochoa-Orozco1 Luis Felipe "riesgo de trastorno de la conducta alimentaria" (RTCA), aun cuando en ocasiones lo que describen es la y uso de escalas diagnósticas en trastornos del comportamiento alimentario (TCA) 921Rev. Colomb
Gràcia, Xavier
LA TEOR´IA DE LA DISONANCIA: UN ENCUENTRO ENTRE M´USICA Y MATEM´ATICAS XAVIER GR`ACIA Dep. Matem´usica y matem´atica Espectros de los instrumentos musicales Teor´ia de las escalas Teor´ia de la agradable. En m´usica, "disonante" no significa necesariamente desagradable! Hay varios conceptos de
Indicadores de Riesgo de Desastre y de Gestión de Riesgo: Aplicación del Sistema de Indicadores a Bolivia 1980 ¿ 2000 (Indice de Déficit por Desastre)
Luis Eduardo Yamín; Omar D. Cardona
Esta presentación fue comisionada por la Red de Desastres Naturales del Diálogo Regional de Política para la VI Reunión Hemisférica celebrada los días 24 y 25 de abril de 2006. El propósito del sistema de indicadores desarrollado en el marco de la operación ATN\\/JF-7907-RG del BID, es dimensionar la vulnerabilidad y el riesgo, usando indicadores a escala nacional, para facilitar
Indicadores de Riesgo de Desastre y de Gestión de Riesgo: Aplicación del Sistema de Indicadores a Bolivia 1980 ¿ 2000 (Indice de Gestión de Riesgos)
Luis Eduardo Yamín; Omar D. Cardona
Esta presentación fue comisionada por la Red de Desastres Naturales del Diálogo Regional de Política para la VI Reunión Hemisférica celebrada los días 24 y 25 de abril de 2006. El propósito del sistema de indicadores desarrollado en el marco de la operación ATN\\/JF-7907-RG del BID, es dimensionar la vulnerabilidad y el riesgo, usando indicadores a escala nacional, para facilitar
Indicadores de Riesgo de Desastre y de Gestión de Riesgo: Aplicación del Sistema de Indicadores a Bolivia 1980 - 2000 (Indice de Desastres Locales y de Vulnerabilidad Prevalente)
Omar D. Cardona; Luis Eduardo Yamín
Esta presentación fue comisionada por la Red de Desastres Naturales del Diálogo Regional de Política para la VI Reunión Hemisférica celebrada los días 24 y 25 de abril de 2006. El propósito del sistema de indicadores desarrollado en el marco de la operación ATN\\/JF-7907-RG del BID, es dimensionar la vulnerabilidad y el riesgo, usando indicadores a escala nacional, para facilitar
Edgar Moreno Castillo
El presente artículo tuvo como objetivo comparar metodologías de análisis desde los sistemas complejos que involucraran elementos sociales y naturales en interacción entre sí y a diferentes escalas, para ser aplicadas en el estudio de proyectos forestales de captura de carbono. Este tipo de proyectos se denominan mecanismos de mitigación al cambio climático, clasificados dentro del Mecanismo de Desarrollo Limpio
Para Divulgacin Inmediata: 28 de junio de 2013 Contacto de Medios: Sandy Louey 916-654-4989
tecnología de captura de carbono a escala comercial. Las 15 secciones técnicas con impactos importantes discusión y/o análisis son: calidad del aire; recursos biológicos; secuestro de carbono y emisiones de gases de gasificación integrada para producir y vender electricidad, dióxido de carbono y fertilizante. El
Precariedad laboral de los jóvenes y segmentación por la edad en Rhône-Alpes : análisis global de las condiciones de empleo y estudio específico los principales sectores terciarios
Irune López-Pérez; Jon Bernat Zubiri-Rey
El periodo neoliberal ha supuesto una regresión en la distribución de excedentes de la economía mercantil. Este proceso se da a escala global y entre clases sociales en cada ámbito localizado, generando una creciente segmentación sociolaboral que se reimpulsa a partir de mediados de los 90 mediante nuevas regulaciones y diversos formatos sectoriales de precarización laboral. La región francesa de
Francine Meca Vignotto; Eduardo Eugenio Spers
O consumidor consciente tem um papel importante na sociedade ao adotar práticas em suas escolhas cotidianas que privilegiam aspectos como sustentabilidade e responsabilidade social. A atividade agrícola é conhecida por seu impacto no meio ambiente e a decisão de minimizá-lo recai em geral sobre um indivíduo, o produtor rural. Com base em uma escala de consciência sobre tratos culturais agrícolas
Alicia Zorrilla
El hombre llamado posmoderno se olvida de que habla y de que escribe, pero habla y escribe con ostentoso descuido, una forma de violencia con la que quiere derribar las murallas de su insatisfacción. Un hombre isla, atrapado por la duda irreverente, por las ansias desmedidas de elevarse sin escrú- pulos y sin esfuerzos en la escala social; a veces,
quien hace una escala para repostar, sólo para restañar las heridas que en su caso devienen en verdaderas mutilaciones, y reemprender luego la marcha, pero finalmente queda anclado en el hogar, reducido a cumplir las funciones de un mero objeto de...
Bergmann, Philip J.
METRIC AMANDA D. MELIN, PHILIP J. BERGMANN,* AND ANTHONY P. RUSSELL Department of Biological Sciences et al. 2000; Green and Fekete 1934; Lammers et al. 2001; Lu 2003; Moss and Baer 1956; Reik et al, and ear length (Garde and Escala 1996; Green and Fekete 1934; Lammers et al. 2001; Lu 2003
The Factor Structure of Preschool Learning Behaviors Scale Scores in Peruvian Children
ERIC Educational Resources Information Center
Hahn, Kathryn R.; Schaefer, Barbara A.; Merino, Cesar; Worrell, Frank C.
The factor structure of the Escala de Conductas de Aprendizaje Preescolar (ECAP), a Spanish translation of the Preschool Learning Behaviors Scale (PLBS), was examined in this study. Children aged 2 to 6 years (N = 328) enrolled in public and private preschools in the Republic of Peru were rated by classroom teachers on the frequency of observable,…
Differences in phytotoxicity and dissipation between ionized and nonionized oil sands naphthenic acids in wetland plants.
Armstrong, Sarah A; Headley, John V; Peru, Kerry M; Germida, James J
Naphthenic acids (NAs) are composed of alkyl-substituted acyclic and cycloaliphatic carboxylic acids and, because they are acutely toxic to fish, are of toxicological concern. During the caustic hot-water extraction of oil from the bitumen in oil sands deposits, NAs become concentrated in the resulting tailings pond water. The present study investigated if dissipation of NAs occurs in the presence of hydroponically grown emergent macrophytes (Typha latifolia, Phragmites australis, and Scirpus acutus) to determine the potential for phytoremediation of these compounds. Plants were grown with oil sands NAs (pKa approximately 5-6) in medium at pH 7.8 (predominantly ionized NAs) and pH 5.0 (predominantly nonionized NAs) to determine if, by altering their chemical form, NAs may be more accessible to plants and, thus, undergo increased dissipation. Whereas the oil sands NA mixture in its nonionized form was more toxic to wetland plants than its ionized form, neither form appeared to be sequestered by wetland plants. The present study demonstrated that plants may selectively enhance the dissipation of individual nonionized NA compounds, which contributes to toxicity reduction but does not translate into detectable total NA dissipation within experimental error and natural variation. Plants were able to reduce the toxicity of a NA system over 30 d, increasing the median lethal concentration (LC50; % of hydroponic solution) of the medium for Daphnia magna by 23.3% +/- 8.1% (mean +/- standard error; nonionized NAs) and 37.0% +/- 2.7% (ionized NAs) as determined by acute toxicity bioassays. This reduction in toxicity was 7.3% +/- 2.6% (nonionized NAs) and 45.0% +/- 6.8% (ionized NAs) greater than that in unplanted systems. PMID:19469588
Naphthenic acids degradation and toxicity mitigation in tailings wastewater systems and aquatic environments: a review.
Kannel, Prakash R; Gan, Thian Y
Naphthenic acids, NAs (classical formula C(n)H(2n+z)O(2), where n is the carbon numbers, z represents zero or negative even integers), found in oil sands process waters (OSPWs), are toxic to aquatic environments depending upon several factors such as pH, salinity, molecular size and chemical structure of NAs. Among various available methods, biodegradation seems to be generally the most cost-effective method for decreasing concentrations of NAs (n ? 21) and reducing their associated toxicity in OSPW, however the mechanism by which the biodegradation of NAs occurs are poorly understood. Ozonation is superior over biodegradation in decreasing higher molecular weight alkyl branched NAs (preferentially, n ? 22, -6 ? z ? -12) as well as enabling accelerated biodegradation and reducing toxicity. Photolysis (UV at 254 nm) is effective in cleaving higher molecular weight NAs into smaller fragments that will be easier for microorganisms to degrade, whereas photocatalysis can metabolize selective NAs (0 ? z ? -6) efficiently and minimize their associated toxicity. Phytoremediation is applicable for metabolizing specific NAs (O(2), O(3), O(4), and O(5) species) and minimizing their associated toxicities. Petroleum coke (PC) adsorption is effective in reducing the more structurally complex NAs (preferentially 12 ? n ? 18 and z = -10, -12) and their toxicity in OSPWs, depending upon the PC content, pH and temperature. Several factors have influence on the degradation of NAs in OSPWs and aquatic environments, which include molecular mass and chemical structure of NAs, sediment structure, temperature, pH, dissolved oxygen, nutrients, and bacteria types. PMID:22217078
1EV GaN[subscript x]As[subscript 1-x-y]Sb[subscript y] material for lattice-matched III-V solar cell implementation on GaAs and Ge
Yoon, Soon Fatt
The effect of different arsenic species (As[subscript 2] or As[subscript 4]) on the quality of molecular beam epitaxy (MBE) grown GaNAsSb materials (samples A and B) and GaAs/ GaNAsSb/GaAs p+n-n+ devices (samples C and D) ...
Work domain analysis for air traffic controller weather displays
Ulf Ahlstrom
Introduction: Adverse weather conditions have a major impact on National Airspace System (NAS) operations. They create safety hazards for pilots, constrain the usable airspace for air traffic control (ATC), and reduce the overall capacity of the NAS. A system-wide dissemination of weather information to controllers could theoretically improve safety and efficiency. Problem: However, it is currently unclear what weather information
Making the Case for New Research to Support the Integration of Small Unmanned Aircraft Systems into the National Airspace System
NASA Technical Reports Server (NTRS)
McAdaragh, Raymon M.; Comstock, James R., Jr.; Ghatas, Rania W.; Burdette, Daniel W.; Trujillo, Anna C.
This paper describes the current state of sUAS regulation, their technical capabilities and the latest technologies that will allow for sUAS NAS integration. The research that is needed to demonstrate sUAS NAS integration capability is identified, and recommendations for conducting this necessary research are suggested.
A Tool for Integrating Commercial Space Operations Into The National Airspace System
Daniel P. Murray
Potential growth in the commercial space transportation industry, coupled with an expected doubling of air traffic operations over the next 10 years, could place additional safety and capacity demands on the National Airspace System (NAS). The Space and Air Traffic Management System (SATMS) is a proposed framework of operations designed to accommodate future commercial space operations within the NAS and
Simão Marinho
Uma discussão sobre a formação de professores que sejam capazes de incorporar as tecnologias digitais na educação como recurso no processo de ensino -aprendizagem nas escolas da educação básica no Brasil passa necessariamente por um questionament o da prática atual das nossas licenciaturas em plena Era da Informação... De uma maneira geral, nas licenciaturas brasileiras ainda não se usam os
Considering the difficulty in measuring restoration success for nonpoint source pollutants, nutrient assimilative capacity (NAS) offers an attractive systems-based metric. Here NAS was defined using an impulse-response model of nitrate fate and transport. Eleven parameters were e...
Innovation on Energy Power Technology (7)Development and Practical Application of Sodium-Sulfur Battery for Electric Energy Storage System
Hideki Rachi
Sodium-Sulfur battery (NAS battery), which has more than 3 times of energy density compared with the conventional lead-acid battery and can be compactly established, has a great installation effects as a distributed energy storage system in the urban area which consumes big electric power. For the power company, NAS battery contributes to the load leveling, the supply capability up at
Novo método de preparação palinológica para aumentar a recuperação de dinoflagelados
RESUMO - O método aqui apresentado tem por objetivo melhorar a recuperação de palinomorfos em amostras de sedimentos quaternários da bacia de Campos. Nas preparações tradicionais, tanto palinológicas quanto de palinofácies, a fração mineral é eliminada por acidificação, com o objetivo de concentrar o maior número possível de palinomorfos e de matéria orgânica nas lâminas. Entretanto, ambas utilizam o descarte
Presentation requested by the National Academy of Science (NAS) for a Colloquium on Water Quality Implications of Biofuels Production, to be held at the NAS in Washington, D.C. on July 12, 2007. This presentation will address the influence of ethanol on hydrocarbon plumes and th...
Airport delay prediction using weather-impacted traffic index (WITI) model
Alexander Klein; Chad Craun; Robert S. Lee
In this paper, we present a new predictive model for estimating airport delay using data from weather forecast products. We use the well established Weather Impacted Traffic Index (WITI) toolset and metric. The latter quantifies the "front-end" impact of weather and traffic demand on the NAS and is well correlated with NAS delays, which makes WITI a reasonably good high-level
Effects of exposure to naphthenic acids in tree swallows (Tachycineta bicolor) on the Athabasca oil sands, Alberta, Canada.
Gentes, Marie-Line; Waldner, Cheryl; Papp, Zsuzsanna; Smits, Judit E G
Naphthenic acids (NAs) are a group of carboxylic acids that are of particular concern to the steadily growing oil sands mining industry of Alberta, Canada, because they become highly concentrated in the water used for oil sands extraction and are toxic to aquatic biota and mammals. Upon mine closure, vast amounts of process-affected water will need to be reclaimed and proven safe for wildlife colonizing reclaimed areas. The effects of exposure to NAs have not been investigated in avian species. To address this void, tree swallow (Tachycineta bicolor) nestlings were dosed with NAs while being reared normally by their free-ranging parents on a site in the vicinity of the oil sands. Nestlings received 1.5 mg NAs/day (approximately 0.075 g/kg body mass) from d 7 to d 13 of age, which represented a 10-fold "worst exposure" scenario. Nestling growth, hematocrit, blood biochemistry, organ weights, and ethoxyresorufin O-deethylase (EROD) activity were unaffected by NAs. The only change detected on histopathological evaluation of major organs was an increase in extramedullary erythropoiesis in the liver. These findings indicate that nestling tree swallows can successfully tolerate short-term exposures to environmentally realistic concentrations of NAs. However, this study did not investigate the chronic or reproductive toxicity of NAs. More research needs to be conducted to complete this initial assessment, to determine environmental risks on reclaimed areas where birds will be breeding and where their exposure to NAs could extend for several weeks. PMID:17573632
Shifts in root-associated microbial communities of Typha latifolia growing in naphthenic acids and relationship to plant health.
Phillips, Lori A; Armstrong, Sarah A; Headley, John V; Greer, Charles W; Germida, James J
Naphthenic acids (NAs) are a complex mixture of organic acid compounds released during the extraction of crude oil from oil sands operations. The accumulation of toxic NAs in tailings pond water (TPW) is of significant environmental concern, and phytoremediation using constructed wetlands is one remediation option being assessed. Since root-associated microorganisms are an important factor during phytoremediation of organic compounds, this study investigated the impact of NAs on the microbial communities associated with the macrophyte Typha latifolia (cattail). Denaturing gradient gel electrophoresis revealed that the impact of NAs on microbial communities was niche dependent, with endophytic communities being the most stable and bulk water communities being the least stable. The type of NA used was significant to microbial response, with commercial NAs causing greater adverse changes than TPW NAs. In general, plant beneficial bacteria such as diazotrophs were favoured in cattails grown in TPW NAs, while potentially deleterious bacteria such as denitrifying Dechlorospirillum species increased in commercial NA treatments. These findings suggest that NAs may affect plant health by impacting root-associated microbial communities. A better understanding of these impacts may allow researchers to optimize those microbial communities that support plant health, and thus further optimize wetland treatment systems. PMID:21166345
High peak alanine aminotransferase determines extra risk for nonanastomotic biliary strictures after liver transplantation with donation after circulatory death.
den Dulk, A Claire; Sebib Korkmaz, Kerem; de Rooij, Bert-Jan F; Sutton, Michael E; Braat, Andries E; Inderson, Akin; Dubbeld, Jeroen; Verspaget, Hein W; Porte, Robert J; van Hoek, Bart
Orthotopic liver transplantation (OLT) with donation after circulatory death (DCD) often leads to a higher first week peak alanine aminotransferase (ALT) and a higher rate of biliary nonanastomotic strictures (NAS) as compared to donation after brain death (DBD). This retrospective study was to evaluate whether an association exists between peak ALT and the development of NAS in OLT with livers from DBD (n = 399) or DCD (n = 97) from two transplantation centers. Optimal cutoff value of peak ALT for risk of development of NAS post-DCD-OLT was 1300 IU/l. The 4-year cumulative incidence of NAS after DCD-OLT was 49.5% in patients with a high ALT peak post-OLT, compared with 11.3% in patients with a low ALT peak. (P < 0.001). No relation between peak ALT and NAS was observed after DBD-OLT. Multivariate analysis revealed peak ALT ?1300 IU/l [adjusted hazard ratio (aHR) = 3.71, confidence interval (CI) (1.26-10.91)] and donor age [aHR = 1.04, CI 1.00-1.07] to be independently associated with development of NAS post-DCD-OLT. A peak ALT of <1300 IU/l carries a risk for NAS similar to DBD-OLT. Thus, in DCD-OLT, but not in DBD-OLT, peak ALT discriminates patients at high or low risk for NAS. PMID:25601020
Naphthenic acids and surrogate naphthenic acids in methanogenic microcosms
Fervone M Holowenko; Michael D MacKinnon; Phillip M Fedorak
Naphthenic acids (NAs) are a complex mixture of naturally occurring acyclic and cyclic aliphatic carboxylic acids in petroleum. In the Athabasca oil sands, NAs have been identified as the largest component of dissolved organic matter in the tailings waters from oils sands extraction processes. They are the major contributor to the acute toxicity of the fine tailings wastewaters at the
Toxicity assessment of collected fractions from an extracted naphthenic acid mixture
Richard A. Frank; Richard Kavanagh; B. Kent Burnison; Gilles Arsenault; John V. Headley; Kerry M. Peru; Glen Van Der Kraak; Keith R. Solomon
Recent expansion within the oil sands industry of the Athabasca Basin of Alberta, Canada has led to increased concern regarding process-affected wastewaters produced during bitumen extraction. Naphthenic acids (NAs) have been identified as the primary toxic constituents of oil sands process-affected waters (OSPW) and studies have shown that with time, microbial degradation of lower molecular weight NAs has led to
Model development for naphthenic acids ozonation process.
Al Jibouri, Ali Kamel H; Wu, Jiangning
Naphthenic acids (NAs) are toxic constituents of oil sands process-affected water (OSPW) which is generated during the extraction of bitumen from oil sands. NAs consist mainly of carboxylic acids which are generally biorefractory. For the treatment of OSPW, ozonation is a very beneficial method. It can significantly reduce the concentration of NAs and it can also convert NAs from biorefractory to biodegradable. In this study, a factorial design (2(4)) was used for the ozonation of OSPW to study the influences of the operating parameters (ozone concentration, oxygen/ozone flow rate, pH, and mixing) on the removal of a model NAs in a semi-batch reactor. It was found that ozone concentration had the most significant effect on the NAs concentration compared to other parameters. An empirical model was developed to correlate the concentration of NAs with ozone concentration, oxygen/ozone flow rate, and pH. In addition, a theoretical analysis was conducted to gain the insight into the relationship between the removal of NAs and the operating parameters. PMID:25189805
Factors that affect the degradation of naphthenic acids in oil sands wastewater by indigenous microbial communities
June W. S. Lai; Linda J. Pinto; Eberhard Kiehlmann; Leah I. Bendell-Young
The acute toxicity of wastewater generated during the extraction of bitumen from oil sands is believed to be due to naphthenic acids (NAs). To determine the factors that affect the rate of degradation of representative NAs in microcosms containing wastewater and the acute toxicity of treated and untreated wastewater, the effects of temperature, dissolved oxygen concentration, and phosphate addition on
The effects of salinity on naphthenic acid toxicity to yellow perch: Gill and liver histopathology
V. Nero; A. Farwell; L. E. J. Lee; T. Van Meer; M. D. MacKinnon; D. G. Dixon
Naphthenic acids (NAs) are naturally occurring saturated linear and cyclic carboxylic acids found in petroleum, including the bitumen contained in the Athabasca Oil Sands deposit in Alberta, Canada. The processing of these oil sands leads to elevated concentrations of NAs, as well as increased salinity from produced waters as a result of ions leaching from the ores, the process aids,
Ozonation attenuates the steroidogenic disruptive effects of sediment free oil sands process water in the H295R cell line
Yuhe He; Steve B. Wiseman; Xiaowei Zhang; Markus Hecker; Paul D. Jones; Mohamed Gamal El-Din; Jonathan W. Martin; John P. Giesy
There is concern regarding oil sands process water (OSPW) produced by the oil sands industry in Alberta, Canada. Little is known about the potential for OSPW, and naphthenic acids (NAs), which are the primary persistent and toxic constituents of OSPW, to affect endocrine systems. Although ozonation significantly reduces concentrations of NAs and OSPW toxicity, it was hypothesized that oxidation of
Naphthenic acid biodegradation by the unicellular alga Dunaliella tertiolecta.
Quesnel, Dean M; Bhaskar, Iyswarya M; Gieg, Lisa M; Chua, Gordon
Naphthenic acids (NAs) are a major contributor to toxicity in tailings waste generated from bitumen production in the Athabasca Oil Sands region. While investigations have shown that bacteria can biodegrade NAs and reduce tailings toxicity, the potential of algae to biodegrade NAs and the biochemical mechanisms involved remain poorly understood. Here, we discovered that the marine alga Dunaliella tertiolecta is able to tolerate five model NAs (cyclohexanecarboxylic acid, cyclohexaneacetic acid, cyclohexanepropionic acid, cyclohexanebutyric acid and 1,2,3,4-tetrahydro-2-naphthoic acid) at 300mgL(-1), a level which exceeds that of any single or combination of NAs typically found in tailings ponds. Moreover, we show that D. tertiolecta can metabolize four of the model NAs. Analysis of NA-amended cultures of D. tertiolecta via low resolution gas chromatography-mass spectrometry allowed us to quantify decreasing NA levels, identify metabolites, and formulate putative mechanisms of biodegradation. Degradation of cyclohexanebutyric acid and cyclohexanepropionic acid proceeded via ?-oxidation and resulted in the transient accumulation of cyclohexaneacetic acid and cyclohexanecarboxylic acid, respectively. Cyclohexanecarboxylic acid was metabolized via 1-cyclohexenecarboxylic acid suggesting that further degradation may occur by step-wise ?-oxidation. When D. tertiolecta was inoculated in the presence of oil sands tailings water from the Athabasca region, biodegradation of single-ring NAs was observed relative to controls. This result corroborates the trend we observed with the single-ring model NAs. PMID:21459409
Limits to growth: results from the detailed policy assessment tool [air traffic congestion
Frederick Wieland
Congestion-induced delay is one of the recognized metrics for assessing performance in the National Airspace System (NAS). Delay can arise from many causes, including factors specific to airline operations as well as factors that can be traced to NAS operations. In this paper we introduce a recently developed tool, the Detailed Policy Assessment Tool (DPAT), and use it to explore
An Analysis of the Effects of Net-Centric Operations Using Multi-Agent Adaptive Behavior
ERIC Educational Resources Information Center
Calderon-Meza, Guillermo
The National Airspace System (NAS) is a resource managed in the public good. Equity in NAS access, and use for private, commercial and government purposes is coordinated by regulations and made possible by procedures, and technology. Researchers have documented scenarios in which the introduction of new concepts-of-operations and technologies has…
78 FR 27015 - Airworthiness Directives; Airbus Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
...Seals with Part Number (P/N) MS28775-XXX or a Part Number that Cannot Be Identified...the seals installed have P/N MS28775-XXX or a part number that cannot be identified...using a new O- ring seal P/N NAS1611-XXX or P/N NAS1611-XXXA, in...
77 FR 48469 - Airworthiness Directives; Airbus Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
...Seals with Part Number (P/N) MS28775-XXX or a Part Number That Cannot Be Identified...the seals installed have P/N MS28775-XXX or a part number that cannot be identified...using a new O- ring seal P/N NAS1611-XXX or P/N NAS1611-XXXA, in...
"What Does Bowdoin Teach"? A Dialogue between Wood and Klingenstein
ERIC Educational Resources Information Center
Wood, Peter; Klingenstein, Tom
This article is an exchange of ideas between Peter Wood, President of the National Association of Scholars (NAS), and Tom Klingerstein, Chairman of the Claremont Institute and NAS Board Director, on the study "What Does Bowdoin Teach? How a Contemporary Liberal Arts College Shapes Students" (by Peter Wood and Michael Toscano). This…
Decisionmaking, Transitions, and Resilient Futures
Moss, Richard H.; Lane, Meredith A.
The article describes the focus of research in the social sciences on environmental change, describing studies on adaptation and mitigation. It is the first of 5 articles in the NAS quarterly journal IS&T on the occasion of the launch of a new Board at the NAS chaired by the author.
Resumo - Começa-se pela apresentação da primeira hipótese posta pelos Autores quanto à idade das gravuras rupestres de Foz Côa, que se baseava nas características climáticas e paleoclimáticas conhecidas para a área, bem como nas características hidrológicas do rio Côa, particularmente no respeitante às cheias, e se apoiava na dedução da origem tardi- glaciar das superfícies lisas onde elas se
Fighting the "Damnable Triumph" of Feminism: Battles between Teachers' Unions in Interwar Britain
ERIC Educational Resources Information Center
Wilson, Dolly Smith
The interwar decades saw a bitter recruiting war between the NUT (National Union of Teachers), the National Union of Women Teachers (NUWT), and the National Association of Schoolmasters (NAS), which like the NUWT broke away from the NUT in the early 1920s. The NAS opposed the NUT's official policy shift to support equal pay for male and female…
Chief of Naval Air Training Resource Planning System (RPS).
ERIC Educational Resources Information Center
Hodak, Gary W.; And Others
The Resource Planning System (RPS) provides the Chief of Naval Air Training (CNATRA) with the capability to determine the resources required to produce a specified number of Naval Aviators and Naval Flight Officers (NAs/NFOs) quickly and efficiently. The training of NAs and NFOs is extremely time consuming and complex. It requires extensive…
Numerical Aerodynamic Simulation
NASA Technical Reports Server (NTRS)
An overview of historical and current numerical aerodynamic simulation (NAS) is given. The capabilities and goals of the Numerical Aerodynamic Simulation Facility are outlined. Emphasis is given to numerical flow visualization and its applications to structural analysis of aircraft and spacecraft bodies. The uses of NAS in computational chemistry, engine design, and galactic evolution are mentioned.
Instituto de Sistemas e Robotica
740 mortos nas Filipinas · Meta para o défice em 2013 deve exigir ... · 50 discos de música jazz que ATUALIDADE ECONOMIA DINHEIRO LIFE & STYLE DESPORTO TECNOLOGIA FOTOS INFOGRAFIA OPINIÃO BLOGUES EMPREGO CASAS a marcar esta ... · Tufão 'Bopha' faz 740 mortos nas Filipinas · Meta para o défice em 2013 deve exigir
Group classification and exact solutions of nonlinear wave equations State Pedagogical University, 2 Ostrogradskogo Street, 36000 Poltava, Ukraine
Zhdanov, Renat
University, 2 Ostrogradskogo Street, 36000 Poltava, Ukraine R. Zhdanov Institute of Mathematics of NAS of Ukraine, 3 Tereshchenkivska Street, 01601 Kyiv, Ukraine O. Magda Institute of Mathematics of NAS of Ukraine, 3 Tereshchenkivska Street, 01601 Kyiv, Ukraine Abstract We perform complete group classification
The Astrophysical Journal, 488:L137L140, 1997 October 20 1997. The American Astronomical Society. All rights reserved. Printed in U.S.A.
Ziurys, Lucy M.
distributions of these molecules in IRC 10216 are at present not known. However, the combined column densities 25 ABSTRACT The sodium sulfide radical NaS has been observed in the laboratory for the first time of sulfur in circumstellar envelopes is the refractory species NaS. Two other sodium-bearing mol- ecules
The USAF Phillips Laboratory sodium-sulfur battery technology program: Results and status
NASA Technical Reports Server (NTRS)
Rainbow, Marc E.; Somerville, Andrew
Tests performed on NaS batteries are reported. The results of safety and abuse testing, shock and vibration tests, cell failure on warm-up, freeze thaw, overtemperature conditions, electrolyte fracture, overdischarge, and short circuit tests are presented along with GEO and LEO cycle tests and the status of the NaS cell flight tests.
Re-analysis of the nuclear winter phenomenon
S. F. Singer
Summary An analysis of the report of the (U.S.) National Academy of Sciences (NAS) on atmospheric effects of a nuclear exchange leads to conclusions that differ from those of the NAS and of the earlier "TTAPS" and "AMBIO" studies. Any cooling of the earth's surface is likely to beshort-lived because of rapid removal of the smoke clouds originating from nuclear
Adoption Practice in Canada: Emerging Trends and Challenges.
ERIC Educational Resources Information Center
Sobol, Michael P.; Daly, Kerry
Reports the results of the National Adoption Study of Canada (NAS), which is based on demographic adoption statistics and a survey of adoption agencies and practitioners. The NAS found that between 1981 and 1990 the number of adoptions decreased by 47% and that private adoptions are accounting for an ever-increasing proportion of infant…
Relationship between Weather, Traffic and Delay Based on Empirical Methods
NASA Technical Reports Server (NTRS)
Sridhar, Banavar; Swei, Sean S. M.
The steady rise in demand for air transportation over the years has put much emphasis on the need for sophisticated air traffic flow management (TFM) within the National Airspace System (NAS). The NAS refers to hardware, software and people, including runways, radars, networks, FAA, airlines, etc., involved in air traffic management (ATM) in the US. One of the metrics that has been used to assess the performance of NAS is the actual delays provided through FAA's Air Traffic Operations Network (OPSNET). The OPSNET delay data includes those reportable delays, i.e. delays of 15 minutes or more experienced by Instrument Flight Rule (IFR) flights, submitted by the FAA facilities. These OPSNET delays are caused by the application of TFM initiatives in response to, for instance, weather conditions, increased traffic volume, equipment outages, airline operations, and runway conditions. TFM initiatives such as, ground stops, ground delay programs, rerouting, airborne holding, and miles-in-trail restrictions, are actions which are needed to control the air traffic demand to mitigate the demand-capacity imbalance due to the reduction in capacity. Consequently, TFM initiatives result in NAS delays. Of all the causes, weather has been identified as the most important causal factor for NAS delays. Therefore, in order to accurately assess the NAS performance, it has become necessary to create a baseline for NAS performance and establish a model which characterizes the relation between weather and NAS delays.
32 CFR 728.33 - Nonavailability statement (DD 1251).
Code of Federal Regulations, 2012 CFR
...on the use of the automated system. At activities where the DEER/NAS automated system is not operational, prepare each DD...the original of each DD 1251 prepared at activities where the DEER/NAS automated system is not operational. Send the...
32 CFR 728.33 - Nonavailability statement (DD 1251).
Code of Federal Regulations, 2013 CFR
...on the use of the automated system. At activities where the DEER/NAS automated system is not operational, prepare each DD...the original of each DD 1251 prepared at activities where the DEER/NAS automated system is not operational. Send the...
32 CFR 728.33 - Nonavailability statement (DD 1251).
Code of Federal Regulations, 2010 CFR
...on the use of the automated system. At activities where the DEER/NAS automated system is not operational, prepare each DD...the original of each DD 1251 prepared at activities where the DEER/NAS automated system is not operational. Send the...
32 CFR 728.33 - Nonavailability statement (DD 1251).
Code of Federal Regulations, 2014 CFR
...on the use of the automated system. At activities where the DEER/NAS automated system is not operational, prepare each DD...the original of each DD 1251 prepared at activities where the DEER/NAS automated system is not operational. Send the...
National Aeronautics and Space Administration
Guattery, Steve
National Aeronautics and Space Administration Langley Research Center Hampton, Virginia 23681, Hampton, VA 23681-0001 (email: firstname.lastname@example.com). This research was supported by the National Aeronautics and Space Administration under NASA Contract Nos. NAS1-97046 and NAS1-19480 while the author
National Aeronautics and Space Administration
Guattery, Steve
National Aeronautics and Space Administration Langley Research Center Hampton, Virginia 23681, Hampton, VA 236810001 (email: email@example.com). This research was supported by the National Aeronautics and Space Administration under NASA Contract Nos. NAS197046 and NAS119480 while the author