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  • Computer Programming and Software  (1.145)
  • Cell & Developmental Biology
  • Fisheries
  • 2000-2004  (1.172)
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  • 1
    Digitale Medien
    Digitale Medien
    Springer
    Agriculture and human values 17 (2000), S. 125-139 
    ISSN: 1572-8366
    Schlagwort(e): Environment ; Fisheries ; Fordism ; Nation-State ; Regulation ; Supranational State ; Transnational corporations ; Transnational State
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Abstract This analysis uses an analytical frameworkgrounded in political economy perspectives of theglobalization of the agro-food sector combined with acase study approach focusing on the Marine StewardshipCouncil (MSC) to inform discussions regarding thecharacteristics of societal regulation in thepost-Fordist era. More specifically, this analysisuses the case of the emergence of the MSC toinvestigate propositions regarding the existence of,and location of, nascent forms of a transnationalState. The MSC proposes to regulate the certificationof sustainable fisheries at the global level throughan eco-labeling program. The MSC was created in 1996by the transnational environmental organization theWorld Wildlife Fund and the transnational corporationUnilever. The emergence of the MSC has generatedheated discussion in fisheries management circles thatis in general divided along North/South lines. Thisanalysis indicates that the case of the MSC providesvaluable insights into the possible characteristics ofsupranational regulatory mechanisms that might emulatethe role of the nation-State in the post-Fordist era.
    Materialart: Digitale Medien
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  • 2
    Digitale Medien
    Digitale Medien
    Springer
    Environment, development and sustainability 2 (2000), S. 277-304 
    ISSN: 1573-2975
    Schlagwort(e): Systems of Knowledge ; Local Knowledge ; Fisheries ; Resource Management
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Energietechnik , Sociologie
    Notizen: Abstract During the last 20 years, the existence of rich systems of local knowledge, and their vital support to resource use and management regimes, has been demonstrated in a wide range of biological, physical and geographical domains, such as agriculture, animal husbandry, forestry and agroforestry, medicine, and marine science and fisheries. Local knowledge includes empirical and practical components that are fundamental to sustainable resource management. Among coastal-marine fishers, for example, regular catches and, often, long-term resource sustainment are ensured through the application of knowledge that encompasses empirical information on fish behaviour, marine physical environments, fish habitats and the interactions among ecosystem components, as well as complex fish taxonomies. Local knowledge is therefore an important cultural resource that guides and sustains the operation of customary management systems. The sets of rules that compose a fisheries management system derive directly from local concepts and knowledge of the resources on which the fishery is based. Beyond the practical and the empirical, it is essential to recognise the fundamental socio-cultural importance of local knowledge to any society. It is through knowledge transmission and socialisation that worldviews are constructed, social institutions perpetuated, customary practices established, and social roles defined. In this manner, local knowledge and its transmission, shape society and culture, and culture and society shape knowledge. Local knowledge is of great potential practical value. It can provide an important information base for local resources management, especially in the tropics, where conventionally-used data are usually scarce to non-existent, as well as providing a shortcut to pinpoint essential scientific research needs. To be useful for resources management, however, it must be systematically collected and scientifically verified, before being blended with complementary information derived from Western-based sciences. But local knowledge should not be looked on with only a short-term utilitarian eye. Arguments widely accepted for conserving biodiversity, for example, are also applicable to the intellectual cultural diversity encompassed in local knowledge systems: they should be conserved because their utility may only be revealed at some later date or owing to their intrinsic value as part of the world's global heritage. At least in cultures with a Western liberal tradition, more than lip-service is now being paid to alternative systems of knowledge. The denigration of alternative knowledge systems as backward, inefficient, inferior, and founded on myth and ignorance has recently begun to change. Many such practices are a logical, sophisticated and often still-evolving adaptation to risk, based on generations of empirical experience and arranged according to principles, philosophies and institutions that are radically different from those prevailing in Western scientific circles, and hence all-but incomprehensible to them. But steadfastly held prejudices remain powerful. In this presentation I describe the 'design principles' of local knowledge systems, with particular reference to coastal-marine fishing communities, and their social and practical usefulness. I then examine the economic, ideological and institutional factors that combine to perpetuate the marginalisation and neglect of local knowledge, and discuss some of the requirements for applying local knowledge in modern management.
    Materialart: Digitale Medien
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  • 3
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    American Association for the Advancement of Science (AAAS)
    Publikationsdatum: 2003-10-11
    Beschreibung: 〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Stone, Richard -- New York, N.Y. -- Science. 2003 Oct 10;302(5643):221-2.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/14551417" target="_blank"〉PubMed〈/a〉
    Schlagwort(e): Animals ; Ecosystem ; *Eels/growth & development/physiology ; Fisheries ; Fresh Water ; Oceans and Seas ; Population Density ; Reproduction ; Seawater
    Print ISSN: 0036-8075
    Digitale ISSN: 1095-9203
    Thema: Biologie , Chemie und Pharmazie , Informatik , Medizin , Allgemeine Naturwissenschaft , Physik
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  • 4
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    American Association for the Advancement of Science (AAAS)
    Publikationsdatum: 2003-08-23
    Beschreibung: 〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Malakoff, David -- New York, N.Y. -- Science. 2003 Aug 22;301(5636):1034-7.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/12933987" target="_blank"〉PubMed〈/a〉
    Schlagwort(e): Animals ; *Anthozoa ; Atlantic Ocean ; Conservation of Natural Resources ; *Ecosystem ; Environment ; Fisheries ; *Fishes ; Geologic Sediments ; *Marine Biology ; Pacific Ocean ; *Seawater
    Print ISSN: 0036-8075
    Digitale ISSN: 1095-9203
    Thema: Biologie , Chemie und Pharmazie , Informatik , Medizin , Allgemeine Naturwissenschaft , Physik
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  • 5
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    American Association for the Advancement of Science (AAAS)
    Publikationsdatum: 2000-08-19
    Beschreibung: At a press conference on 27 July, the National Marine Fisheries Service (NMFS) released a long-awaited plan to save the Columbia River's endangered salmon by restoring fish habitat, overhauling hatcheries, limiting harvest, and improving river flow. What the plan did not do, however, was call for immediate breaching of four dams on the Snake River, the Columbia's major tributary--an option that has been the subject of a nationwide environmental crusade. The NMFS will hold that option in abeyance while it sees whether the less drastic measures will do the trick. Responses from both sides were immediate and outraged.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Mann, C C -- Plummer, M L -- New York, N.Y. -- Science. 2000 Aug 4;289(5480):716-9.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/10950712" target="_blank"〉PubMed〈/a〉
    Schlagwort(e): Animals ; *Conservation of Natural Resources ; *Ecosystem ; Fisheries ; Fresh Water ; Government Agencies ; Northwestern United States ; *Salmon
    Print ISSN: 0036-8075
    Digitale ISSN: 1095-9203
    Thema: Biologie , Chemie und Pharmazie , Informatik , Medizin , Allgemeine Naturwissenschaft , Physik
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  • 6
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    American Association for the Advancement of Science (AAAS)
    Publikationsdatum: 2001-08-18
    Beschreibung: 〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Magnuson, J J -- Safina, C -- Sissenwine, M P -- New York, N.Y. -- Science. 2001 Aug 17;293(5533):1267-8.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Center for Limnology, University of Wisconsin, Madison, WI 53706, USA. jmagnuson@mhub.limnology.wisc.edu〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/11509715" target="_blank"〉PubMed〈/a〉
    Schlagwort(e): Animal Identification Systems ; Animals ; Atlantic Ocean ; *Behavior, Animal ; Body Temperature ; *Conservation of Natural Resources ; Diving ; *Ecosystem ; Fisheries ; Population Dynamics ; Reproduction ; Swimming ; Tuna/genetics/*physiology
    Print ISSN: 0036-8075
    Digitale ISSN: 1095-9203
    Thema: Biologie , Chemie und Pharmazie , Informatik , Medizin , Allgemeine Naturwissenschaft , Physik
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  • 7
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    American Association for the Advancement of Science (AAAS)
    Publikationsdatum: 2001-03-20
    Beschreibung: 〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Malakoff, D -- New York, N.Y. -- Science. 2001 Jan 12;291(5502):227-9.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/11253825" target="_blank"〉PubMed〈/a〉
    Schlagwort(e): Animals ; Fisheries ; *Homing Behavior ; Isotopes ; Otolithic Membrane/*chemistry ; Perciformes/*physiology ; Population Dynamics ; Reproduction ; United States
    Print ISSN: 0036-8075
    Digitale ISSN: 1095-9203
    Thema: Biologie , Chemie und Pharmazie , Informatik , Medizin , Allgemeine Naturwissenschaft , Physik
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  • 8
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    American Association for the Advancement of Science (AAAS)
    Publikationsdatum: 2001-02-24
    Beschreibung: 〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Collie, J -- Saila, S -- Walters, C -- Carpenter, S -- New York, N.Y. -- Science. 2000 Nov 3;290(5493):933-4.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/11184733" target="_blank"〉PubMed〈/a〉
    Schlagwort(e): Animals ; Conservation of Natural Resources ; *Ecosystem ; Fisheries ; Fresh Water ; Government Agencies ; Models, Biological ; Northwestern United States ; Population Dynamics ; *Salmon/physiology
    Print ISSN: 0036-8075
    Digitale ISSN: 1095-9203
    Thema: Biologie , Chemie und Pharmazie , Informatik , Medizin , Allgemeine Naturwissenschaft , Physik
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  • 9
    Publikationsdatum: 2000-10-29
    Beschreibung: The effects of climate variability on Pacific salmon abundance are uncertain because historical records are short and are complicated by commercial harvesting and habitat alteration. We use lake sediment records of delta15N and biological indicators to reconstruct sockeye salmon abundance in the Bristol Bay and Kodiak Island regions of Alaska over the past 300 years. Marked shifts in populations occurred over decades during this period, and some pronounced changes appear to be related to climatic change. Variations in salmon returns due to climate or harvesting can have strong impacts on sockeye nursery lake productivity in systems where adult salmon carcasses are important nutrient sources.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Finney, B P -- Gregory-Eaves, I -- Sweetman, J -- Douglas, M S -- Smol, J P -- New York, N.Y. -- Science. 2000 Oct 27;290(5492):795-9.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Institute of Marine Science, University of Alaska Fairbanks, Fairbanks, AK 99775, USA. finney@ims.uaf.edu〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/11052941" target="_blank"〉PubMed〈/a〉
    Schlagwort(e): Alaska ; Animals ; *Climate ; Diatoms ; *Ecosystem ; Fisheries ; Fresh Water ; Geologic Sediments/chemistry ; Industry ; Nitrogen Isotopes/analysis ; Pacific Ocean ; Plankton ; Salmon/*physiology ; Temperature
    Print ISSN: 0036-8075
    Digitale ISSN: 1095-9203
    Thema: Biologie , Chemie und Pharmazie , Informatik , Medizin , Allgemeine Naturwissenschaft , Physik
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  • 10
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    American Association for the Advancement of Science (AAAS)
    Publikationsdatum: 2001-07-28
    Beschreibung: 〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Zimmer, C -- New York, N.Y. -- Science. 2001 Jul 27;293(5530):627-8.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/11474097" target="_blank"〉PubMed〈/a〉
    Schlagwort(e): Animals ; *Cnidaria ; *Ecosystem ; Eutrophication ; Fisheries ; International Cooperation ; Israel ; Jordan ; Marine Biology ; Oceans and Seas ; Time Factors ; United States
    Print ISSN: 0036-8075
    Digitale ISSN: 1095-9203
    Thema: Biologie , Chemie und Pharmazie , Informatik , Medizin , Allgemeine Naturwissenschaft , Physik
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  • 11
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    American Association for the Advancement of Science (AAAS)
    Publikationsdatum: 2002-08-07
    Beschreibung: 〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Ajayi, Thomas -- Sherman, Kenneth -- Tang, Qisheng -- New York, N.Y. -- Science. 2002 Aug 2;297(5582):772.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/12162321" target="_blank"〉PubMed〈/a〉
    Schlagwort(e): Biomass ; Conservation of Natural Resources/*economics/*methods/trends ; *Ecosystem ; Europe ; Fisheries ; International Cooperation ; *Marine Biology/economics/trends ; North America ; Water Pollution/prevention & control
    Print ISSN: 0036-8075
    Digitale ISSN: 1095-9203
    Thema: Biologie , Chemie und Pharmazie , Informatik , Medizin , Allgemeine Naturwissenschaft , Physik
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  • 12
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    American Association for the Advancement of Science (AAAS)
    Publikationsdatum: 2001-02-24
    Beschreibung: Using a novel technique, described on page 795, paleoceanographers have been able to chart the abundance of sockeye salmon in the Bristol Bay and Kodiak Island regions of Alaska over the past 300 years--by far the most complete record yet. Through time, they found, sockeye populations have alternately soared and slipped, following natural climate variations--well before commercial fishers began throwing nets over the sides of boats.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Brown, K -- New York, N.Y. -- Science. 2000 Oct 27;290(5492):685-6.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/11184190" target="_blank"〉PubMed〈/a〉
    Schlagwort(e): Alaska ; Animals ; *Climate ; *Ecosystem ; Fisheries ; Fresh Water ; Geologic Sediments/chemistry ; Nitrogen Isotopes/analysis ; Pacific Ocean ; Salmon/*physiology ; Temperature
    Print ISSN: 0036-8075
    Digitale ISSN: 1095-9203
    Thema: Biologie , Chemie und Pharmazie , Informatik , Medizin , Allgemeine Naturwissenschaft , Physik
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  • 13
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    American Association for the Advancement of Science (AAAS)
    Publikationsdatum: 2000-05-08
    Beschreibung: Fish faunas across the continental United States have become more similar through time because of widespread introductions of a group of cosmopolitan species intended to enhance food and sport fisheries. On average, pairs of states have 15.4 more species in common now than before European settlement of North America. The 89 pairs of states that formerly had no species in common now share an average of 25.2 species. Introductions have played a larger role than extirpations in homogenizing fish faunas. Western and New England states have received the most introductions, which is a reflection of the small number of native fishes in these areas considered desirable gamefish by settlers.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Rahel, F J -- New York, N.Y. -- Science. 2000 May 5;288(5467):854-6.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Zoology and Physiology, University of Wyoming, Laramie, WY 82071, USA. frahel@uwyo.edu〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/10797007" target="_blank"〉PubMed〈/a〉
    Schlagwort(e): Animals ; *Ecosystem ; Fisheries ; *Fishes ; Species Specificity ; United States
    Print ISSN: 0036-8075
    Digitale ISSN: 1095-9203
    Thema: Biologie , Chemie und Pharmazie , Informatik , Medizin , Allgemeine Naturwissenschaft , Physik
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  • 14
    Publikationsdatum: 2001-08-18
    Beschreibung: The deployment of electronic data storage tags that are surgically implanted or satellite-linked provides marine researchers with new ways to examine the movements, environmental preferences, and physiology of pelagic vertebrates. We report the results obtained from tagging of Atlantic bluefin tuna with implantable archival and pop-up satellite archival tags. The electronic tagging data provide insights into the seasonal movements and environmental preferences of this species. Bluefin tuna dive to depths of 〉1000 meters and maintain a warm body temperature. Western-tagged bluefin tuna make trans-Atlantic migrations and they frequent spawning grounds in the Gulf of Mexico and eastern Mediterranean. These data are critical for the future management and conservation of bluefin tuna in the Atlantic.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Block, B A -- Dewar, H -- Blackwell, S B -- Williams, T D -- Prince, E D -- Farwell, C J -- Boustany, A -- Teo, S L -- Seitz, A -- Walli, A -- Fudge, D -- New York, N.Y. -- Science. 2001 Aug 17;293(5533):1310-4.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Tuna Research and Conservation Center, Stanford University, Hopkins Marine Station, Oceanview Boulevard, Pacific Grove, CA 93950, USA. bblock@stanford.edu〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/11509729" target="_blank"〉PubMed〈/a〉
    Schlagwort(e): Animal Identification Systems ; Animals ; Atlantic Ocean ; *Behavior, Animal ; Body Temperature ; Conservation of Natural Resources ; Diving ; *Ecosystem ; Female ; Fisheries ; Male ; Reproduction ; Seasons ; Swimming ; Temperature ; Tuna/*physiology
    Print ISSN: 0036-8075
    Digitale ISSN: 1095-9203
    Thema: Biologie , Chemie und Pharmazie , Informatik , Medizin , Allgemeine Naturwissenschaft , Physik
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  • 15
    Publikationsdatum: 2003-07-05
    Beschreibung: 〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Sanchirico, James N -- Stoffle, Richard -- Broad, Kenny -- Talaue-McManus, Liana -- New York, N.Y. -- Science. 2003 Jul 4;301(5629):47-9; author reply 47-9.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/12843376" target="_blank"〉PubMed〈/a〉
    Schlagwort(e): Animals ; California ; *Conservation of Natural Resources ; *Ecosystem ; Fisheries ; *Fishes ; Humans ; Seawater
    Print ISSN: 0036-8075
    Digitale ISSN: 1095-9203
    Thema: Biologie , Chemie und Pharmazie , Informatik , Medizin , Allgemeine Naturwissenschaft , Physik
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  • 16
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    American Association for the Advancement of Science (AAAS)
    Publikationsdatum: 2003-04-05
    Beschreibung: 〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Service, Robert F -- New York, N.Y. -- Science. 2003 Apr 4;300(5616):36-9.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/12677035" target="_blank"〉PubMed〈/a〉
    Schlagwort(e): Agriculture ; Animals ; California ; *Conservation of Natural Resources ; *Cypriniformes/physiology ; *Ecology ; Ecosystem ; Environment ; Fisheries ; *Fresh Water ; Government Agencies ; National Academy of Sciences (U.S.) ; *Oncorhynchus kisutch/physiology ; Oregon ; United States ; Water Movements
    Print ISSN: 0036-8075
    Digitale ISSN: 1095-9203
    Thema: Biologie , Chemie und Pharmazie , Informatik , Medizin , Allgemeine Naturwissenschaft , Physik
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  • 17
    Publikationsdatum: 2004-11-13
    Beschreibung: The multibillion-dollar trade in bushmeat is among the most immediate threats to the persistence of tropical vertebrates, but our understanding of its underlying drivers and effects on human welfare is limited by a lack of empirical data. We used 30 years of data from Ghana to link mammal declines to the bushmeat trade and to spatial and temporal changes in the availability of fish. We show that years of poor fish supply coincided with increased hunting in nature reserves and sharp declines in biomass of 41 wildlife species. Local market data provide evidence of a direct link between fish supply and subsequent bushmeat demand in villages and show bushmeat's role as a dietary staple in the region. Our results emphasize the urgent need to develop cheap protein alternatives to bushmeat and to improve fisheries management by foreign and domestic fleets to avert extinctions of tropical wildlife.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Brashares, Justin S -- Arcese, Peter -- Sam, Moses K -- Coppolillo, Peter B -- Sinclair, A R E -- Balmford, Andrew -- New York, N.Y. -- Science. 2004 Nov 12;306(5699):1180-3.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Conservation Biology Group, Department of Zoology, University of Cambridge, Cambridge CB2 3EJ, UK. brashares@nature.berkeley.edu〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/15539602" target="_blank"〉PubMed〈/a〉
    Schlagwort(e): Agriculture ; Animals ; *Animals, Wild ; Biodiversity ; Biomass ; Commerce ; Conservation of Natural Resources ; Fisheries ; *Fishes ; *Food Supply ; Ghana ; Humans ; *Mammals ; *Meat ; Population Density ; Population Dynamics
    Print ISSN: 0036-8075
    Digitale ISSN: 1095-9203
    Thema: Biologie , Chemie und Pharmazie , Informatik , Medizin , Allgemeine Naturwissenschaft , Physik
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  • 18
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    American Association for the Advancement of Science (AAAS)
    Publikationsdatum: 2004-08-31
    Beschreibung: 〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Grimm, David -- New York, N.Y. -- Science. 2004 Aug 27;305(5688):1235.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/15333821" target="_blank"〉PubMed〈/a〉
    Schlagwort(e): Animals ; Biodiversity ; *Ecosystem ; Fisheries ; *Fishes ; Humans ; Population Density ; *Recreation ; United States
    Print ISSN: 0036-8075
    Digitale ISSN: 1095-9203
    Thema: Biologie , Chemie und Pharmazie , Informatik , Medizin , Allgemeine Naturwissenschaft , Physik
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  • 19
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    American Association for the Advancement of Science (AAAS)
    Publikationsdatum: 2004-09-14
    Beschreibung: It is now widely accepted that global warming is occurring, yet its effects on the world's largest ecosystem, the marine pelagic realm, are largely unknown. We show that sea surface warming in the Northeast Atlantic is accompanied by increasing phytoplankton abundance in cooler regions and decreasing phytoplankton abundance in warmer regions. This impact propagates up the food web (bottom-up control) through copepod herbivores to zooplankton carnivores because of tight trophic coupling. Future warming is therefore likely to alter the spatial distribution of primary and secondary pelagic production, affecting ecosystem services and placing additional stress on already-depleted fish and mammal populations.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Richardson, Anthony J -- Schoeman, David S -- New York, N.Y. -- Science. 2004 Sep 10;305(5690):1609-12.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Sir Alister Hardy Foundation for Ocean Science, The Laboratory, Citadel Hill, Plymouth, PL1 2PB, UK. anr@sahfos.ac.uk〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/15361622" target="_blank"〉PubMed〈/a〉
    Schlagwort(e): Animals ; Atlantic Ocean ; *Climate ; Copepoda/*growth & development ; *Ecosystem ; Fisheries ; Fishes ; *Food Chain ; Greenhouse Effect ; Meta-Analysis as Topic ; Phytoplankton/*growth & development ; Population Dynamics ; Seawater ; Temperature ; Zooplankton/*growth & development
    Print ISSN: 0036-8075
    Digitale ISSN: 1095-9203
    Thema: Biologie , Chemie und Pharmazie , Informatik , Medizin , Allgemeine Naturwissenschaft , Physik
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  • 20
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    American Association for the Advancement of Science (AAAS)
    Publikationsdatum: 2004-08-25
    Beschreibung: 〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Proffitt, Fiona -- New York, N.Y. -- Science. 2004 Aug 20;305(5687):1090.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/15326320" target="_blank"〉PubMed〈/a〉
    Schlagwort(e): Animals ; Birds/*physiology ; *Ecosystem ; *Eels ; Fisheries ; Food Chain ; North Sea ; Plankton ; Population Density ; *Reproduction ; Scotland ; Seawater ; Temperature
    Print ISSN: 0036-8075
    Digitale ISSN: 1095-9203
    Thema: Biologie , Chemie und Pharmazie , Informatik , Medizin , Allgemeine Naturwissenschaft , Physik
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  • 21
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    American Association for the Advancement of Science (AAAS)
    Publikationsdatum: 2004-06-26
    Beschreibung: 〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Wright, Bruce A -- Okey, Thomas A -- New York, N.Y. -- Science. 2004 Jun 25;304(5679):1903.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/15218125" target="_blank"〉PubMed〈/a〉
    Schlagwort(e): Animals ; *Conservation of Natural Resources ; *Ecosystem ; *Environment ; Fisheries ; Humans ; Information Dissemination ; Population Growth ; Public Policy
    Print ISSN: 0036-8075
    Digitale ISSN: 1095-9203
    Thema: Biologie , Chemie und Pharmazie , Informatik , Medizin , Allgemeine Naturwissenschaft , Physik
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  • 22
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    Unbekannt
    American Association for the Advancement of Science (AAAS)
    Publikationsdatum: 2004-08-25
    Beschreibung: 〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Allison, Edward H -- Seeley, Janet A -- New York, N.Y. -- Science. 2004 Aug 20;305(5687):1104.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/15326332" target="_blank"〉PubMed〈/a〉
    Schlagwort(e): Asia/epidemiology ; Female ; Fisheries ; HIV Infections/*epidemiology/transmission ; Humans ; Male ; Occupations ; Prevalence ; Sexual Partners ; *Transients and Migrants
    Print ISSN: 0036-8075
    Digitale ISSN: 1095-9203
    Thema: Biologie , Chemie und Pharmazie , Informatik , Medizin , Allgemeine Naturwissenschaft , Physik
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  • 23
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    Unbekannt
    American Association for the Advancement of Science (AAAS)
    Publikationsdatum: 2003-05-10
    Beschreibung: 〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Zimmer, Carl -- New York, N.Y. -- Science. 2003 May 9;300(5621):895.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/12738833" target="_blank"〉PubMed〈/a〉
    Schlagwort(e): Animals ; *Biological Evolution ; Breeding ; *Conservation of Natural Resources ; Environment ; Fisheries ; *Fishes/genetics/growth & development/physiology ; Plant Development ; Reproduction ; *Selection, Genetic ; Sexual Maturation
    Print ISSN: 0036-8075
    Digitale ISSN: 1095-9203
    Thema: Biologie , Chemie und Pharmazie , Informatik , Medizin , Allgemeine Naturwissenschaft , Physik
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  • 24
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    Unbekannt
    American Association for the Advancement of Science (AAAS)
    Publikationsdatum: 2004-07-27
    Beschreibung: 〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Rembold, Christopher M -- New York, N.Y. -- Science. 2004 Jul 23;305(5683):475; author reply 475.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/15273376" target="_blank"〉PubMed〈/a〉
    Schlagwort(e): Animals ; Coronary Artery Disease/mortality/*prevention & control ; *Diet ; Environmental Pollutants/toxicity ; Fatty Acids, Omega-3/*administration & dosage ; Fisheries ; *Food Contamination ; Humans ; Neoplasms/chemically induced/epidemiology ; Randomized Controlled Trials as Topic ; Risk Assessment ; *Salmon ; Toxicity Tests
    Print ISSN: 0036-8075
    Digitale ISSN: 1095-9203
    Thema: Biologie , Chemie und Pharmazie , Informatik , Medizin , Allgemeine Naturwissenschaft , Physik
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  • 25
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    Unbekannt
    American Association for the Advancement of Science (AAAS)
    Publikationsdatum: 2004-09-14
    Beschreibung: 〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Stokstad, Erik -- New York, N.Y. -- Science. 2004 Sep 10;305(5690):1548-9.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/15361593" target="_blank"〉PubMed〈/a〉
    Schlagwort(e): Animals ; Atlantic Ocean ; *Climate ; *Ecosystem ; Fisheries ; *Food Chain ; Phytoplankton/*growth & development ; Population Dynamics ; Seawater ; Temperature ; Zooplankton/*growth & development
    Print ISSN: 0036-8075
    Digitale ISSN: 1095-9203
    Thema: Biologie , Chemie und Pharmazie , Informatik , Medizin , Allgemeine Naturwissenschaft , Physik
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  • 26
    Publikationsdatum: 2002-12-10
    Beschreibung: There is debate concerning the most effective conservation of marine biodiversity, especially regarding the appropriate location, size, and connectivity of marine reserves. We describe a means of establishing marine reserve networks by using optimization algorithms and multiple levels of information on biodiversity, ecological processes (spawning, recruitment, and larval connectivity), and socioeconomic factors in the Gulf of California. A network covering 40% of rocky reef habitat can fulfill many conservation goals while reducing social conflict. This quantitative approach provides a powerful tool for decision-makers tasked with siting marine reserves.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Sala, Enric -- Aburto-Oropeza, Octavio -- Paredes, Gustavo -- Parra, Ivan -- Barrera, Juan C -- Dayton, Paul K -- New York, N.Y. -- Science. 2002 Dec 6;298(5600):1991-3.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Center for Marine Biodiversity and Conservation, Scripps Institution of Oceanography, La Jolla, CA 92093, USA. esala@ucsd.edu〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/12471258" target="_blank"〉PubMed〈/a〉
    Schlagwort(e): Animals ; California ; Computer Simulation ; *Conservation of Natural Resources ; *Ecosystem ; Environment ; Fisheries ; Fishes ; Invertebrates ; *Models, Biological ; *Seawater
    Print ISSN: 0036-8075
    Digitale ISSN: 1095-9203
    Thema: Biologie , Chemie und Pharmazie , Informatik , Medizin , Allgemeine Naturwissenschaft , Physik
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  • 27
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    American Association for the Advancement of Science (AAAS)
    Publikationsdatum: 2003-08-30
    Beschreibung: 〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Webster, Paul -- New York, N.Y. -- Science. 2003 Aug 29;301(5637):1167.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/12947169" target="_blank"〉PubMed〈/a〉
    Schlagwort(e): Animals ; *Conservation of Natural Resources/economics ; *Ecosystem ; *Environment ; Financial Support ; Fisheries ; Fresh Water ; Pacific Ocean ; Russia ; *Salmon ; United Nations/economics
    Print ISSN: 0036-8075
    Digitale ISSN: 1095-9203
    Thema: Biologie , Chemie und Pharmazie , Informatik , Medizin , Allgemeine Naturwissenschaft , Physik
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  • 28
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    In:  Other Sources
    Publikationsdatum: 2011-08-31
    Beschreibung: The NASA's Intelligent Synthesis Environment (ISE) program is a grand attempt to develop a system to transform the way complex artifacts are engineered. This paper discusses a "middleware" architecture for enabling the development of ISE. Desirable elements of such an Intelligent Synthesis Architecture (ISA) include remote invocation; plug-and-play applications; scripting of applications; management of design artifacts, tools, and artifact and tool attributes; common system services; system management; and systematic enforcement of policies. This paper argues that the ISA extend conventional distributed object technology (DOT) such as CORBA and Product Data Managers with flexible repositories of product and tool annotations and "plug-and-play" mechanisms for inserting "ility" or orthogonal concerns into the system. I describe the Object Infrastructure Framework, an Aspect Oriented Programming (AOP) environment for developing distributed systems that provides utility insertion and enables consistent annotation maintenance. This technology can be used to enforce policies such as maintaining the annotations of artifacts, particularly the provenance and access control rules of artifacts-, performing automatic datatype transformations between representations; supplying alternative servers of the same service; reporting on the status of jobs and the system; conveying privileges throughout an application; supporting long-lived transactions; maintaining version consistency; and providing software redundancy and mobility.
    Schlagwort(e): Computer Programming and Software
    Format: text
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  • 29
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    Unbekannt
    In:  Other Sources
    Publikationsdatum: 2011-08-24
    Beschreibung: Program generation and transformation systems work on two language levels, the object-level (i e., the language of the manipulated programs), and the meta-level (i.e., the implementation language of the system itself). The meta-level representations of object-level program fragments are usually built in an essentially syntax-free fashion using the operations provided by the meta-language. However, syntax matters and a large conceptual distance between the two languages makes it difficult to maintain and extend such systems. Here we describe how an existing Prolog-based system can gradually be retrofitted with concrete object-level syntax, thus shrinking this distance.
    Schlagwort(e): Computer Programming and Software
    Materialart: Logic-Based Program Synthesis and Transformation: LOPSTER 2003, Revised
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  • 30
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    In:  CASI
    Publikationsdatum: 2004-12-03
    Beschreibung: Kinematic and dynamic analyses for moving bodies are essential to system engineers and designers in the process of design and validations. 3D visualization and motion simulation plus finite element analysis (FEA) give engineers a better way to present ideas and results. Marshall Space Flight Center (MSFC) system engineering researchers are currently using IGRIP from DELMIA Inc. as a kinematic simulation tool for discrete bodies motion simulations. Although IGRIP is an excellent tool for kinematic simulation with some dynamic analysis capabilities in robotic control, explorations of other alternatives with more powerful dynamic analysis and FEA capabilities are necessary. Kinematics analysis will only examine the displacement, velocity, and acceleration of the mechanism without considering effects from masses of components. With dynamic analysis and FEA, effects such as the forces or torques at the joint due to mass and inertia of components can be identified. With keen market competition, ALGOR Mechanical Event Simulation (MES), MSC visualNastran 4D, Unigraphics Motion+, and Pro/MECHANICA were chosen for explorations. In this study, comparisons between software tools were presented in terms of following categories: graphical user interface (GUI), import capability, tutorial availability, ease of use, kinematic simulation capability, dynamic simulation capability, FEA capability, graphical output, technical support, and cost. Propulsion Test Article (PTA) with Fastrac engine model exported from IGRIP and an office chair mechanism were used as examples for simulations.
    Schlagwort(e): Computer Programming and Software
    Materialart: Research Reports: 2001 NASA/ASEE Summer Faculty Fellowship Program; XLVII-1 - XLVII-5; NASA/CR-2002-211840
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  • 31
    Publikationsdatum: 2004-12-03
    Beschreibung: In this viewgraph presentation, information is provided on the numerical simulation of a turbulence event encountered by NASA Langley's B-757 while conducting flight tests in areas at high risk for severe turbulence. Specific details on the Terminal Area Simulation System (TASS) show how the simulation is devised. The 100 m simulation was able to observe large-scale features.
    Schlagwort(e): Computer Programming and Software
    Materialart: Proceedings of the Second NASA Aviation Safety Program Weather Accident Prevention Review; 510-536; NASA/CP-2003-210964
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  • 32
    Publikationsdatum: 2004-12-03
    Beschreibung: This viewgraph presentation provides information on two experiments on the effectiveness of a cockpit weather information system on a simulated general aviation flight. The presentation covers the simulation hardware configuration, the display device screen layout, a mission scenario, conclusions, and recommendations. The second experiment, with its own scenario and conclusions, is a follow-on experiment.
    Schlagwort(e): Computer Programming and Software
    Materialart: Proceedings of the Second NASA Aviation Safety Program Weather Accident Prevention Review; 257-288; NASA/CP-2003-210964
    Format: text
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  • 33
    Publikationsdatum: 2013-08-31
    Beschreibung: The process of designing and analyzing a multiple-reflector system has traditionally been time-intensive, requiring large amounts of both computational and human time. At many frequencies, a discrete approximation of the radiation integral may be used to model the system. The code which implements this physical optics (PO) algorithm was developed at the Jet Propulsion Laboratory. It analyzes systems of antennas in pairs, and for each pair, the analysis can be computationally time-consuming. Additionally, the antennas must be described using a local coordinate system for each antenna, which makes it difficult to integrate the design into a multi-disciplinary framework in which there is traditionally one global coordinate system, even before considering deforming the antenna as prescribed by external structural and/or thermal factors. Finally, setting up the code to correctly analyze all the antenna pairs in the system can take a fair amount of time, and introduces possible human error. The use of parallel computing to reduce the computational time required for the analysis of a given pair of antennas has been previously discussed. This paper focuses on the other problems mentioned above. It will present a methodology and examples of use of an automated tool that performs the analysis of a complete multiple-reflector system in an integrated multi-disciplinary environment (including CAD modeling, and structural and thermal analysis) at the click of a button. This tool, named MOD Tool (Millimeter-wave Optics Design Tool), has been designed and implemented as a distributed tool, with a client that runs almost identically on Unix, Mac, and Windows platforms, and a server that runs primarily on a Unix workstation and can interact with parallel supercomputers with simple instruction from the user interacting with the client.
    Schlagwort(e): Computer Programming and Software
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  • 34
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    In:  CASI
    Publikationsdatum: 2016-06-07
    Beschreibung: In this project we continued the development of a visual editor in the Java programming language to create screens on which to display real-time data. The data comes from the numerous systems monitoring the operation of the space shuttle while on the ground and in space, and from the many tests of subsystems. The data can be displayed on any computer platform running a Java-enabled World Wide Web (WWW) browser and connected to the Internet. Previously a special-purpose program bad been written to display data on emulations of character-based display screens used for many years at NASA. The goal now is to display bit-mapped screens created by a visual editor. We report here on the visual editor that creates the display screens. This project continues the work we bad done previously. Previously we had followed the design of the 'beanbox,' a prototype visual editor created by Sun Microsystems. We abandoned this approach and implemented a prototype using a more direct approach. In addition, our prototype is based on newly released Java 2 graphical user interface (GUI) libraries. The result has been a visually more appealing appearance and a more robust application.
    Schlagwort(e): Computer Programming and Software
    Materialart: 1999 Research Reports: NASA/ASEE Summer Faculty Fellowship Program; 189-195; NASA/CR-1999-208586
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  • 35
    Publikationsdatum: 2016-06-07
    Beschreibung: This paper describes two separate efforts that used the SPIN model checker to verify deep space autonomy flight software. The first effort occurred at the beginning of a spiral development process and found five concurrency errors early in the design cycle that the developers acknowledge would not have been found through testing. This effort required a substantial manual modeling effort involving both abstraction and translation from the prototype LISP code to the PROMELA language used by SPIN. This experience and others led to research to address the gap between formal method tools and the development cycle used by software developers. The Java PathFinder tool which directly translates from Java to PROMELA was developed as part of this research, as well as automatic abstraction tools. In 1999 the flight software flew on a space mission, and a deadlock occurred in a sibling subsystem to the one which was the focus of the first verification effort. A second quick-response "cleanroom" verification effort found the concurrency error in a short amount of time. The error was isomorphic to one of the concurrency errors found during the first verification effort. The paper demonstrates that formal methods tools can find concurrency errors that indeed lead to loss of spacecraft functions, even for the complex software required for autonomy. Second, it describes progress in automatic translation and abstraction that eventually will enable formal methods tools to be inserted directly into the aerospace software development cycle.
    Schlagwort(e): Computer Programming and Software
    Materialart: Lfm2000: Fifth NASA Langley Formal Methods Workshop; NASA/CP-2000-210100
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  • 36
    Publikationsdatum: 2013-08-29
    Beschreibung: The Unified Modeling Language (UML) is gaining wide popularity for the design of object-oriented systems. UML combines various object-oriented graphical design notations under one common framework. A major factor for the broad acceptance of UML is that it can be conveniently used in a highly iterative, Use Case (or scenario-based) process (although the process is not a part of UML). Here, the (pre-) requirements for the software are specified rather informally as Use Cases and a set of scenarios. A scenario can be seen as an individual trace of a software artifact. Besides first sketches of a class diagram to illustrate the static system breakdown, scenarios are a favorite way of communication with the customer, because scenarios describe concrete interactions between entities and are thus easy to understand. Scenarios with a high level of detail are often expressed as sequence diagrams. Later in the design and implementation stage (elaboration and implementation phases), a design of the system's behavior is often developed as a set of statecharts. From there (and the full-fledged class diagram), actual code development is started. Current commercial UML tools support this phase by providing code generators for class diagrams and statecharts. In practice, it can be observed that the transition from requirements to design to code is a highly iterative process. In this talk, a set of algorithms is presented which perform reasonable synthesis and transformations between different UML notations (sequence diagrams, Object Constraint Language (OCL) constraints, statecharts). More specifically, we will discuss the following transformations: Statechart synthesis, introduction of hierarchy, consistency of modifications, and "design-debugging".
    Schlagwort(e): Computer Programming and Software
    Materialart: IJCAR 2001; Unknown|PMD 2001; Unknown
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  • 37
    Publikationsdatum: 2013-08-29
    Beschreibung: Satellite instruments provide global maps of surface ultraviolet (UV) irradiance by combining backscattered radiance measurements with radiative transfer models. The models are limited by uncertainties in input parameters of the atmosphere and the surface. We evaluate the effects of possible enhancements of the current Total Ozone Mapping Spectrometer (TOMS) surface UV irradiance algorithm focusing on effects of diurnal variation of cloudiness and improved treatment of snow/ice. The emphasis is on comparison between the results of the current (version 1) TOMS UV algorithm and each of the changes proposed. We evaluate different approaches for improved treatment of pixel average cloud attenuation, with and without snow/ice on the ground. In addition to treating clouds based only on the measurements at the local time of the TOMS observations, the results from other satellites and weather assimilation models can be used to estimate attenuation of the incident UV irradiance throughout the day. A new method is proposed to obtain a more realistic treatment of snow covered terrain. The method is based on a statistical relation between UV reflectivity and snow depth. The new method reduced the bias between the TOMS UV estimations and ground-based UV measurements for snow periods. The improved (version 2) algorithm will be applied to re-process the existing TOMS UV data record (since 1978) and to the future satellite sensors (e.g., Quik/TOMS, GOME, OMI on EOS/Aura and Triana/EPIC).
    Schlagwort(e): Computer Programming and Software
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  • 38
    facet.materialart.
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    In:  CASI
    Publikationsdatum: 2013-08-29
    Beschreibung: Autonomous software holds the promise of new operation possibilities, easier design and development, and lower operating costs. However, as those system close control loops and arbitrate resources on-board with specialized reasoning, the range of possible situations becomes very large and uncontrollable from the outside, making conventional scenario-based testing very inefficient. Analytic verification and validation (V&V) techniques, and model checking in particular, can provide significant help for designing autonomous systems in a more efficient and reliable manner, by providing a better coverage and allowing early error detection. This article discusses the general issue of V&V of autonomy software, with an emphasis towards model-based autonomy, model-checking techniques, and concrete experiments at NASA.
    Schlagwort(e): Computer Programming and Software
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  • 39
    Publikationsdatum: 2013-08-29
    Beschreibung: We describe an event-based, publish-and-subscribe mechanism based on using 'smart subscriptions' to recognize weakly-structured events. We present a hierarchy of subscription languages (propositional, predicate, temporal and agent) and algorithms for efficiently recognizing event matches. This mechanism has been applied to the management of distributed applications.
    Schlagwort(e): Computer Programming and Software
    Materialart: Distributed Objects in Computational Science; Unknown
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  • 40
    Publikationsdatum: 2013-08-29
    Beschreibung: This paper analyzes the use of Computer Aided Design (CAD) packages at NASA's Marshall Space Flight Center (MSFC). It examines the effectiveness of recent efforts to standardize CAD practices across MSFC engineering activities. An assessment of the roles played by management, designers, analysts, and manufacturers in this initiative will be explored. Finally, solutions are presented for better integration of CAD across MSFC in the future.
    Schlagwort(e): Computer Programming and Software
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  • 41
    Publikationsdatum: 2013-08-29
    Beschreibung: We present an iterative technique in which model checking and static analysis are combined to verify large software systems. The role of the static analysis is to compute partial order information which the model checker uses to reduce the state space. During exploration, the model checker also computes aliasing information that it gives to the static analyzer which can then refine its analysis. The result of this refined analysis is then fed back to the model checker which updates its partial order reduction. At each step of this iterative process, the static analysis computes optimistic information which results in an unsafe reduction of the state space. However we show that the process converges to a fired point at which time the partial order information is safe and the whole state space is explored.
    Schlagwort(e): Computer Programming and Software
    Materialart: Automated Software Engineering 2001; San Diego, CA; United States
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  • 42
    Publikationsdatum: 2013-08-29
    Beschreibung: A number of known techniques for improving cache performance in scientific computations involve the reordering of the iteration space. Some of these reorderings can be considered as coverings of the iteration space with the sets having good surface-to-volume ratio. Use of such sets reduces the number of cache misses in computations of local operators having the iteration space as a domain. First, we derive lower bounds which any algorithm must suffer while computing a local operator on a grid. Then we explore coverings of iteration spaces represented by structured and unstructured grids which allow us to approach these lower bounds. For structured grids we introduce a covering by successive minima tiles of the interference lattice of the grid. We show that the covering has low surface-to-volume ratio and present a computer experiment showing actual reduction of the cache misses achieved by using these tiles. For planar unstructured grids we show existence of a covering which reduces the number of cache misses to the level of structured grids. On the other hand, we present a triangulation of a 3-dimensional cube such that any local operator on the corresponding grid has significantly larger number of cache misses than a similar operator on a structured grid.
    Schlagwort(e): Computer Programming and Software
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  • 43
    Publikationsdatum: 2013-08-29
    Beschreibung: Soft temporal constraint problems allow to describe in a natural way scenarios where events happen over time and preferences are associated to event distances and durations. However, sometimes such local preferences are difficult to set, and it may be easier instead to associate preferences to some complete solutions of the problem. To model everything in a uniform way via local preferences only, and also to take advantage of the existing constraint solvers which exploit only local preference use machine learning techniques which learn the local preferences from the global ones. In this paper we describe the existing framework for both solving and learning preferences in temporal constraint problems, the implemented modules, the experimental scenario, and preliminary results on some examples.
    Schlagwort(e): Computer Programming and Software
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  • 44
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    In:  CASI
    Publikationsdatum: 2013-08-29
    Beschreibung: When using model checking to verify programs in practice, it is not usually possible to achieve complete coverage of the system. In this position paper we describe ongoing research within the Automated Software Engineering group at NASA Ames on the use of test coverage metrics to measure partial coverage and provide heuristic guidance for program model checking. We are specifically interested in applying and developing coverage metrics for concurrent programs that might be used to support certification of next generation avionics software.
    Schlagwort(e): Computer Programming and Software
    Materialart: WAPATV Workshop; Unknown|International Conference on Software Engineering WAPATV Workshop; Unknown
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  • 45
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    Unbekannt
    In:  CASI
    Publikationsdatum: 2013-08-29
    Beschreibung: This paper shows that if one is provided with a loss function, it can be used in a natural way to specify a distance measure quantifying the similarity of any two supervised learning algorithms, even non-parametric algorithms. Intuitively, this measure gives the fraction of targets and training sets for which the expected performance of the two algorithms differs significantly. Bounds on the value of this distance are calculated for the case of binary outputs and 0-1 loss, indicating that any two learning algorithms are almost exactly identical for such scenarios. As an example, for any two algorithms A and B, even for small input spaces and training sets, for less than 2e(-50) of all targets will the difference between A's and B's generalization performance of exceed 1%. In particular, this is true if B is bagging applied to A, or boosting applied to A. These bounds can be viewed alternatively as telling us, for example, that the simple English phrase 'I expect that algorithm A will generalize from the training set with an accuracy of at least 75% on the rest of the target' conveys 20,000 bytes of information concerning the target. The paper ends by discussing some of the subtleties of extending the distance measure to give a full (non-parametric) differential geometry of the manifold of learning algorithms.
    Schlagwort(e): Computer Programming and Software
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  • 46
    Publikationsdatum: 2013-08-29
    Beschreibung: In this paper, we discuss our approach to making the behavior of planetary rovers more robust for the purpose of increased productivity. Due to the inherent uncertainty in rover exploration, the traditional approach to rover control is conservative, limiting the autonomous operation of the rover and sacrificing performance for safety. Our objective is to increase the science productivity possible within a single uplink by allowing the rover's behavior to be specified with flexible, contingent plans and by employing dynamic plan adaptation during execution. We have deployed a system exhibiting flexible, contingent execution; this paper concentrates on our ongoing efforts on plan adaptation, Plans can be revised in two ways: plan steps may be deleted, with execution continuing with the plan suffix; and the current plan may be merged with an "alternate plan" from an on-board library. The plan revision action is chosen to maximize the expected utility of the plan. Plan merging and action deletion constitute a more conservative general-purpose planning system; in return, our approach is more efficient and more easily verified, two important criteria for deployed rovers.
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  • 47
    Publikationsdatum: 2013-08-29
    Beschreibung: This paper proposes that the distinguishing characteristic of Aspect-Oriented Programming (AOP) systems is that they allow programming by making quantified programmatic assertions over programs written by programmers oblivious to such assertions. Thus, AOP systems can be analyzed with respect to three critical dimensions: the kinds of quantifications allowed, the nature of the actions that can be asserted, and the mechanism for combining base-level actions with asserted actions. Consequences of this perspective are the recognition that certain systems are not AOP and that some mechanisms are expressive enough to allow programming an AOP system within them. A corollary is that while AOP can be applied to Object-Oriented Programming, it is an independent concept applicable to other programming styles.
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  • 48
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    In:  CASI
    Publikationsdatum: 2013-08-29
    Beschreibung: This report will be provided each quarter as a source for reliability, radiation results, NASA capabilities, and other information on programmable logic devices and related applications. This quarter will continue a series of notes concentrating on analysis techniques with this issue's section discussing the use of Root-Sum-Square calculations for digital delays.
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  • 49
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    In:  CASI
    Publikationsdatum: 2013-08-29
    Beschreibung: In this first of two papers, strong limits on the accuracy of physical computation are established. First it is proven that there cannot be a physical computer C to which one can pose any and all computational tasks concerning the physical universe. Next it is proven that no physical computer C can correctly carry out any computational task in the subset of such tasks that can be posed to C. This result holds whether the computational tasks concern a system that is physically isolated from C, or instead concern a system that is coupled to C. As a particular example, this result means that there cannot be a physical computer that can, for any physical system external to that computer, take the specification of that external system's state as input and then correctly predict its future state before that future state actually occurs; one cannot build a physical computer that can be assured of correctly 'processing information faster than the universe does'. The results also mean that there cannot exist an infallible, general-purpose observation apparatus, and that there cannot be an infallible, general-purpose control apparatus. These results do not rely on systems that are infinite, and/or non-classical, and/or obey chaotic dynamics. They also hold even if one uses an infinitely fast, infinitely dense computer, with computational powers greater than that of a Turing Machine. This generality is a direct consequence of the fact that a novel definition of computation - a definition of 'physical computation' - is needed to address the issues considered in these papers. While this definition does not fit into the traditional Chomsky hierarchy, the mathematical structure and impossibility results associated with it have parallels in the mathematics of the Chomsky hierarchy. The second in this pair of papers presents a preliminary exploration of some of this mathematical structure, including in particular that of prediction complexity, which is a 'physical computation analogue' of algorithmic information complexity. It is proven in that second paper that either the Hamiltonian of our universe proscribes a certain type of computation, or prediction complexity is unique (unlike algorithmic information complexity), in that there is one and only version of it that can be applicable throughout our universe.
    Schlagwort(e): Computer Programming and Software
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  • 50
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    In:  CASI
    Publikationsdatum: 2013-08-29
    Beschreibung: This column will be provided each quarter as a source for reliability, radiation results, NASA capabilities, and other information on programmable logic devices and related applications. This quarter will start a series of notes concentrating on analysis techniques with this issues section discussing worst-case analysis requirements.
    Schlagwort(e): Computer Programming and Software
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  • 51
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    In:  CASI
    Publikationsdatum: 2013-08-29
    Beschreibung: This paper describes a translator called JAVA PATHFINDER from JAVA to PROMELA, the "programming language" of the SPIN model checker. The purpose is to establish a framework for verification and debugging of JAVA programs based on model checking. This work should be seen in a broader attempt to make formal methods applicable "in the loop" of programming within NASA's areas such as space, aviation, and robotics. Our main goal is to create automated formal methods such that programmers themselves can apply these in their daily work (in the loop) without the need for specialists to manually reformulate a program into a different notation in order to analyze the program. This work is a continuation of an effort to formally verify, using SPIN, a multi-threaded operating system programmed in Lisp for the Deep-Space 1 spacecraft, and of previous work in applying existing model checkers and theorem provers to real applications.
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  • 52
    Publikationsdatum: 2013-08-29
    Beschreibung: This report describes the development of the NASA Goddard Space Flight Center Virtual Science Fair, including its history and outgrowth from the traditional regional science fairs supported by NASA. The results of the 1999 Virtual Science Fair pilot program, the mechanics of running the 2000 Virtual Science Fair and its results, and comments and suggestions for future Virtual Science Fairs are provided. The appendices to the report contain supporting documentation, including the original proposal for this project, the judging criteria, the user's guide and the judge's guide to the Virtual Science Fair Web site, the Fair publicity brochure and the Fair award designs, judges' and students' responses to survey questions about the Virtual Science Fair, and lists of student entries to both the 1999 and 2000 Fairs.
    Schlagwort(e): Computer Programming and Software
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  • 53
    Publikationsdatum: 2013-08-29
    Beschreibung: The problem of testing a linear temporal logic (LTL) formula on a finite execution trace of events, generated by an executing program, occurs naturally in runtime analysis of software. We present an algorithm which takes an LTL formula and generates an efficient dynamic programming algorithm. The generated algorithm tests whether the LTL formula is satisfied by a finite trace of events given as input. The generated algorithm runs in linear time, its constant depending on the size of the LTL formula. The memory needed is constant, also depending on the size of the formula.
    Schlagwort(e): Computer Programming and Software
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  • 54
    Publikationsdatum: 2013-08-29
    Beschreibung: Living and working on Mars will require model-based computer systems for maintaining and controlling complex life support, communication, transportation, and power systems. This technology must work properly on the first three-year mission, augmenting human autonomy, without adding-yet more complexity to be diagnosed and repaired. One design method is to work with scientists in analog (mars-like) setting to understand how they prefer to work, what constrains will be imposed by the Mars environment, and how to ameliorate difficulties. We describe how we are using empirical requirements analysis to prototype model-based tools at a research station in the High Canadian Arctic.
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  • 55
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    In:  CASI
    Publikationsdatum: 2013-08-29
    Beschreibung: We describe the Object Infrastructure Framework, a system that seeks to simplify the creation of distributed applications by injecting behavior on the communication paths between components. We touch on some of the ilities and services that can be achieved with injector technology, and then focus on the uses of redirecting injectors, injectors that take requests directed at a particular server and generate requests directed at others. We close by noting that OIF is an Aspect-Oriented Programming system, and comparing OIF to related work.
    Schlagwort(e): Computer Programming and Software
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  • 56
    Publikationsdatum: 2013-08-29
    Beschreibung: This paper describes an active (real time) recognition strategy whereby information is inferred iteratively across several viewpoints in descent imagery. We will show how we use inverse theory within the context of parametric model generation, namely height and spectral reflection functions, to generate model assertions. Using this strategy in an active context implies that, from every viewpoint, the proposed system must refine its hypotheses taking into account the image and the effect of uncertainties as well. The proposed system employs probabilistic solutions to the problem of iteratively merging information (images) from several viewpoints. This involves feeding the posterior distribution from all previous images as a prior for the next view. Novel approaches will be developed to accelerate the inversion search using novel statistic implementations and reducing the model complexity using foveated vision. Foveated vision refers to imagery where the resolution varies across the image. In this paper, we allow the model to be foveated where the highest resolution region is called the foveation region. Typically, the images will have dynamic control of the location of the foveation region. For descent imagery in the Entry, Descent, and Landing (EDL) process, it is possible to have more than one foveation region. This research initiative is directed towards descent imagery in connection with NASA's EDL applications. Three-Dimensional Model Recognition, Generation, Fusion, Update, and Refinement (RGFUR or RG4) for height and the spectral reflection characteristics are in focus for various reasons, one of which is the prospect that their interpretation will provide for real time active vision for automated EDL.
    Schlagwort(e): Computer Programming and Software
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  • 57
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    In:  CASI
    Publikationsdatum: 2013-08-29
    Beschreibung: Virtual Environments provide a natural setting for a wide range of information visualization applications, particularly wlieit the information to be visualized is defined on a three-dimensional domain (Bryson, 1996). This chapter provides an overview of the issues that arise when designing and implementing an information visualization application in a virtual environment. Many design issues that arise, such as, e.g., issues of display, user tracking are common to any application of virtual environments. In this chapter we focus on those issues that are special to information visualization applications, as issues of wider concern are addressed elsewhere in this book.
    Schlagwort(e): Computer Programming and Software
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  • 58
    Publikationsdatum: 2013-08-29
    Beschreibung: This paper describes how two runtime analysis algorithms, an existing data race detection algorithm and a new deadlock detection algorithm, have been implemented to analyze Java programs. Runtime analysis is based on the idea of executing the program once. and observing the generated run to extract various kinds of information. This information can then be used to predict whether other different runs may violate some properties of interest, in addition of course to demonstrate whether the generated run itself violates such properties. These runtime analyses can be performed stand-alone to generate a set of warnings. It is furthermore demonstrated how these warnings can be used to guide a model checker, thereby reducing the search space. The described techniques have been implemented in the b e grown Java model checker called PathFinder.
    Schlagwort(e): Computer Programming and Software
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  • 59
    Publikationsdatum: 2013-08-29
    Beschreibung: FutureFlight Central will permit integration of tomorrow's technologies in a risk-free simulation of any airport, airfield, and tower cab environment. The facility provides an opportunity for airlines to mitigate passenger delays by fine tuning airport hub operations, gate management and ramp movement procedures. It also allows airport managers an opportunity to study effects of various improvements at their airports. Finally, it enables air traffic controllers to provide feedback and to become familiar with new airport operations and technologies before final installation.
    Schlagwort(e): Computer Programming and Software
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  • 60
    Publikationsdatum: 2013-08-29
    Beschreibung: Surface profiles were generated by a fractal algorithm and haptically rendered on a force feedback joystick, Subjects were asked to use the joystick to explore pairs of surfaces and report to the experimenter which of the surfaces they felt was rougher. Surfaces were characterized by their root mean square (RMS) amplitude and their fractal dimension. The most important factor affecting the perceived roughness of the fractal surfaces was the RMS amplitude of the surface. When comparing surfaces of fractal dimension 1.2-1.35 it was found that the fractal dimension was negatively correlated with perceived roughness.
    Schlagwort(e): Computer Programming and Software
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  • 61
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    In:  CASI
    Publikationsdatum: 2013-08-29
    Beschreibung: Circular coinduction is a technique for behavioral reasoning that extends cobasis coinduction to specifications with circularities. Because behavioral satisfaction is not recursively enumerable, no algorithm can work for every behavioral statement. However. algorithms using circular coinduction can prove every practical behavioral result that we know. This paper proves the correctness of circular coinduction and some consequences.
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  • 62
    Publikationsdatum: 2013-08-29
    Beschreibung: It is likely that NASA's future spacecraft systems will consist of distributed processes which will handle dynamically varying workloads in response to perceived scientific events, the spacecraft environment, spacecraft anomalies and user commands. Since all situations and possible uses of sensors cannot be anticipated during pre-deployment phases, an approach for dynamically adapting the allocation of distributed computational and communication resources is needed. To address this, we are evolving the DeSiDeRaTa adaptive resource management approach to enable reconfigurable ground and space information systems. The DeSiDeRaTa approach embodies a set of middleware mechanisms for adapting resource allocations, and a framework for reasoning about the real-time performance of distributed application systems. The framework and middleware will be extended to accommodate (1) the dynamic aspects of intra-constellation network topologies, and (2) the complete real-time path from the instrument to the user. We are developing a ground-based testbed that will enable NASA to perform early evaluation of adaptive resource management techniques without the expense of first deploying them in space. The benefits of the proposed effort are numerous, including the ability to use sensors in new ways not anticipated at design time; the production of information technology that ties the sensor web together; the accommodation of greater numbers of missions with fewer resources; and the opportunity to leverage the DeSiDeRaTa project's expertise, infrastructure and models for adaptive resource management for distributed real-time systems.
    Schlagwort(e): Computer Programming and Software
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  • 63
    Publikationsdatum: 2013-08-29
    Beschreibung: 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.
    Schlagwort(e): Computer Programming and Software
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  • 64
    Publikationsdatum: 2013-08-29
    Beschreibung: AUTOBAYES is a fully automatic program synthesis system for the statistical data analysis domain. Its input is a concise description of a data analysis problem in the form of a statistical model; its output is optimized and fully documented C/C++ code which can be linked dynamically into the Matlab and Octave environments. AUTOBAYES synthesizes code by a schema-guided deductive process. Schemas (i.e., code templates with associated semantic constraints) are applied to the original problem and recursively to emerging subproblems. AUTOBAYES complements this approach by symbolic computation to derive closed-form solutions whenever possible. In this paper, we concentrate on the interaction between the symbolic computations and the deductive synthesis process. A statistical model specifies for each problem variable (i.e., data or parameter) its properties and dependencies in the form of a probability distribution, A typical data analysis task is to estimate the best possible parameter values from the given observations or measurements. The following example models normal-distributed data but takes prior information (e.g., from previous experiments) on the data's mean value and variance into account.
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  • 65
    Publikationsdatum: 2013-08-29
    Beschreibung: Software development for NASA missions is a particularly challenging task. Missions are extremely ambitious scientifically, have very strict time frames, and must be accomplished with a maximum degree of reliability. Verification technologies must therefore be pushed far beyond their current capabilities. Moreover, reuse and adaptation of software architectures and components must be incorporated in software development within and across missions. This paper discusses NASA applications that we are currently investigating from these perspectives.
    Schlagwort(e): Computer Programming and Software
    Materialart: Software Engineering CBSE4 Workshop; United States
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  • 66
    Publikationsdatum: 2013-08-29
    Beschreibung: This paper describes work on the verification of HSTS, the planner and scheduler of the Remote Agent autonomous control system deployed in Deep Space 1 (DS1). The verification is done using UPPAAL, a real time model checking tool. We start by motivating our work in the introduction. Then we give a brief description of HSTS and UPPAAL. After that, we give a mapping of HSTS models into UPPAAL and we present samples of plan model properties one may want to verify. Finally, we conclude with a summary.
    Schlagwort(e): Computer Programming and Software
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  • 67
    Publikationsdatum: 2013-08-29
    Beschreibung: In the late 80's, when the author started working at the Goddard Space Flight Center (GSFC) for the National Aeronautics and Space Administration (NASA), several scientists there were in the process of formulating the next generation of Earth viewing science instruments, the Moderate Resolution Imaging Spectroradiometer (MODIS). The instrument would have over thirty spectral bands and would transmit enormous data through the communications channel. This was when the author was assigned the task of investigating lossless compression algorithms for space implementation to compress science data in order to reduce the requirement on bandwidth and storage.
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  • 68
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    In:  CASI
    Publikationsdatum: 2013-08-29
    Beschreibung: In the first of this pair of papers, it was proven that there cannot be a physical computer to which one can properly pose any and all computational tasks concerning the physical universe. It was then further proven that no physical computer C can correctly carry out all computational tasks that can be posed to C. As a particular example, this result means that no physical computer that can, for any physical system external to that computer, take the specification of that external system's state as input and then correctly predict its future state before that future state actually occurs; one cannot build a physical computer that can be assured of correctly "processing information faster than the universe does". These results do not rely on systems that are infinite, and/or non-classical, and/or obey chaotic dynamics. They also hold even if one uses an infinitely fast, infinitely dense computer, with computational powers greater than that of a Turing Machine. This generality is a direct consequence of the fact that a novel definition of computation - "physical computation" - is needed to address the issues considered in these papers, which concern real physical computers. While this novel definition does not fit into the traditional Chomsky hierarchy, the mathematical structure and impossibility results associated with it have parallels in the mathematics of the Chomsky hierarchy. This second paper of the pair presents a preliminary exploration of some of this mathematical structure. Analogues of Chomskian results concerning universal Turing Machines and the Halting theorem are derived, as are results concerning the (im)possibility of certain kinds of error-correcting codes. In addition, an analogue of algorithmic information complexity, "prediction complexity", is elaborated. A task-independent bound is derived on how much the prediction complexity of a computational task can differ for two different reference universal physical computers used to solve that task, a bound similar to the "encoding" bound governing how much the algorithm information complexity of a Turing machine calculation can differ for two reference universal Turing machines. Finally, it is proven that either the Hamiltonian of our universe proscribes a certain type of computation, or prediction complexity is unique (unlike algorithmic information complexity), in that there is one and only version of it that can be applicable throughout our universe.
    Schlagwort(e): Computer Programming and Software
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  • 69
    Publikationsdatum: 2013-08-29
    Beschreibung: We consider the design of multi-agent systems so as to optimize an overall world utility function when (1) those systems lack centralized communication and control, and (2) each agents runs a distinct Reinforcement Learning (RL) algorithm. A crucial issue in such design problems is to initialize/update each agent's private utility function, so as to induce best possible world utility. Traditional 'team game' solutions to this problem sidestep this issue and simply assign to each agent the world utility as its private utility function. In previous work we used the 'Collective Intelligence' framework to derive a better choice of private utility functions, one that results in world utility performance up to orders of magnitude superior to that ensuing from use of the team game utility. In this paper we extend these results. We derive the general class of private utility functions that both are easy for the individual agents to learn and that, if learned well, result in high world utility. We demonstrate experimentally that using these new utility functions can result in significantly improved performance over that of our previously proposed utility, over and above that previous utility's superiority to the conventional team game utility.
    Schlagwort(e): Computer Programming and Software
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  • 70
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    In:  CASI
    Publikationsdatum: 2013-08-31
    Beschreibung: This paper presents the aspects of language programming transformations that were unknown in the early 1980's.
    Schlagwort(e): Computer Programming and Software
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  • 71
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    In:  CASI
    Publikationsdatum: 2013-08-31
    Beschreibung: Phase II will focus on the development of the on-board aircraft networking portion of the testbed which includes the subnet and router configuration and investigation of QoS issues. This implementation of the testbed will consist of a workstation, which functions as the end system, connected to a router. The router will service two subnets that provide data to the cockpit and the passenger cabin. During the testing, data will be transferred between the end systems and those on both subnets. QoS issues will be identified and a preliminary scheme will be developed. The router will be configured for the testbed network and initial security studies will be initiated. In addition, architecture studies of both the SITA and Immarsat networks will be conducted.
    Schlagwort(e): Computer Programming and Software
    Materialart: Interm Summary Reports
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  • 72
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    In:  CASI
    Publikationsdatum: 2013-08-31
    Beschreibung: As NASA develops plans for more and more ambitious missions into space, it is the job of NASA's researchers to develop the technologies that will make those planed missions feasible. One such technology is energy conversion. Energy is all around us; it is in the light that we see in the chemical bonds that hold compounds together, and in mass itself.Energy is the fundamental building block of our universe, yet it has always been straggle for humans to convert this energy into useable forms, like electricity. For space-based applications, NASA requires efficient energy conversion method that require little or no fuel.
    Schlagwort(e): Computer Programming and Software
    Materialart: Interm Summary Reports
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  • 73
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    In:  CASI
    Publikationsdatum: 2013-08-31
    Beschreibung: How are scientists going to make use of the Internet several years from now? This is a case study of a leading-edge experiment in building a 'virtual institute'-- using electronic communication tools to foster collaboration among geographically dispersed scientists. Our experience suggests: Scientists will want to use web-based document management systems. There will be a demand for Internet-enabled meeting support tools. While internet videoconferencing will have limited value for scientists, webcams will be in great demand as a tool for transmitting pictures of objects and settings, rather than "talking heads." and a significant share of scientists who do fieldwork will embrace mobile voice, data and video communication tools. The setting for these findings is a research consortium called the NASA Astrobiology Institute.
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  • 74
    Publikationsdatum: 2013-08-31
    Beschreibung: The purpose of this paper is to provide a description of NASA JPL Distributed Systems Technology (DST) Section's object-oriented component approach to open inter-operable systems software development and software reuse. It will address what is meant by the terminology object component software, give an overview of the component-based development approach and how it relates to infrastructure support of software architectures and promotes reuse, enumerate on the benefits of this approach, and give examples of application prototypes demonstrating its usage and advantages. Utilization of the object-oriented component technology approach for system development and software reuse will apply to several areas within JPL, and possibly across other NASA Centers.
    Schlagwort(e): Computer Programming and Software
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  • 75
    Publikationsdatum: 2011-08-23
    Beschreibung: In this paper, we briefly describe our efforts to develop complex simulation systems. We focus first on four key infrastructure items: enterprise computational services, simulation synthesis, geometry modeling and mesh generation, and a fluid flow solver for arbitrary meshes. We conclude by presenting three diverse applications developed using these technologies.
    Schlagwort(e): Computer Programming and Software
    Materialart: 38th JANNAF Combustion Subcommittee Meeting; Volume 1; 471-478; CPIA-Publ-712-Vol-1
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  • 76
    Publikationsdatum: 2013-08-29
    Beschreibung: This paper describes the proposed agent-based architecture of the Aviation Data Integration System (ADIS). ADIS is a software system that provides integrated heterogeneous data to support aviation problem-solving activities. Examples of aviation problem-solving activities include engineering troubleshooting, incident and accident investigation, routine flight operations monitoring, safety assessment, maintenance procedure debugging, and training assessment. A wide variety of information is typically referenced when engaging in these activities. Some of this information includes flight recorder data, Automatic Terminal Information Service (ATIS) reports, Jeppesen charts, weather data, air traffic control information, safety reports, and runway visual range data. Such wide-ranging information cannot be found in any single unified information source. Therefore, this information must be actively collected, assembled, and presented in a manner that supports the users problem-solving activities. This information integration task is non-trivial and presents a variety of technical challenges. ADIS has been developed to do this task and it permits integration of weather, RVR, radar data, and Jeppesen charts with flight data. ADIS has been implemented and used by several airlines FOQA teams. The initial feedback from airlines is that such a system is very useful in FOQA analysis. Based on the feedback from the initial deployment, we are developing a new version of the system that would make further progress in achieving following goals of our project.
    Schlagwort(e): Computer Programming and Software
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  • 77
    Publikationsdatum: 2013-08-29
    Beschreibung: Most evolutionary approaches to fault recovery in FPGAs focus on evolving alternative logic configurations as opposed to evolving the intra-cell routing. Since the majority of transistors in a typical FPGA are dedicated to interconnect, nearly 80% according to one estimate, evolutionary fault-recovery systems should benefit hy accommodating routing. In this paper, we propose an evolutionary fault-recovery system employing a genetic representation that takes into account both logic and routing configurations. Experiments were run using a software model of the Xilinx Virtex FPGA. We report that using four Virtex combinational logic blocks, we were able to evolve a 100% accurate quadrature decoder finite state machine in the presence of a stuck-at-zero fault.
    Schlagwort(e): Computer Programming and Software
    Materialart: 5th International Conference on Evolvable Systems; Unknown
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  • 78
    Publikationsdatum: 2013-08-29
    Beschreibung: Code certification is a lightweight approach to formally demonstrate software quality. It concentrates on aspects of software quality that can be defined and formalized via properties, e.g., operator safety or memory safety. Its basic idea is to require code producers to provide formal proofs that their code satisfies these quality properties. The proofs serve as certificates which can be checked independently, by the code consumer or by certification authorities, e.g., the FAA. It is the idea underlying such approaches as proof-carrying code [6]. Code certification can be viewed as a more practical version of traditional Hoare-style program verification. The properties to be verified are fairly simple and regular so that it is often possible to use an automated theorem prover to automatically discharge all emerging proof obligations. Usually, however, the programmer must still splice auxiliary annotations (e.g., loop invariants) into the program to facilitate the proofs. For complex properties or larger programs this quickly becomes the limiting factor for the applicability of current certification approaches.
    Schlagwort(e): Computer Programming and Software
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  • 79
    Publikationsdatum: 2016-06-07
    Beschreibung: The ability to exchange information between different engineering software (i.e, CAD, CAE, CAM) is necessary to aid in collaborative engineering. There are a number of different ways to accomplish this goal. One popular method is to transfer data via different file formats. However this method can lose data and becomes complex as more file formats are added. Another method is to use a standard protocol. STEP is one such standard. This paper gives an overview of STEP, provides a list of where to access more information, and develops guidelines to aid the reader in deciding if STEP is appropriate for his/her use.
    Schlagwort(e): Computer Programming and Software
    Materialart: 1999 Research Reports: NASA/ASEE Summer Faculty Fellowship Program; 23-32; NASA/CR-1999-208586
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  • 80
    Publikationsdatum: 2016-06-07
    Beschreibung: One of the most costly errors committed during the development of an element to be used in the space industry is the lack of communication between design and manufacturing engineers. A very important tool that should be utilized in the development stages by both design and manufacturing disciplines is rapid prototyping. Communication levels are intensified with the injection of functional models that are generated from a drawing. At the Marshall Space Flight Center, this discipline is utilized on a more frequent basis as a manner by which hardware may be tested for design and material compatibility.
    Schlagwort(e): Computer Programming and Software
    Materialart: Proceedings of the 4th Conference on Aerospace Materials, Processes, and Environmental Technology; NASA/CP-2001-210427
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  • 81
    Publikationsdatum: 2016-06-07
    Beschreibung: The radiation environment in space is a complex problem to model. Trying to extrapolate the projections of that environment into all areas of the internal spacecraft geometry is even more daunting. With the support of our CERN colleagues, our research group in Houston is embarking on a project to develop a radiation transport tool that is tailored to the problem of taking the external radiation flux incident on any particular spacecraft and simulating the evolution of that flux through a geometrically accurate model of the spacecraft material. The output will be a prediction of the detailed nature of the resulting internal radiation environment within the spacecraft as well as its secondary albedo. Beyond doing the physics transport of the incident flux, the software tool we are developing will provide a self-contained stand-alone object-oriented analysis and visualization infrastructure. It will also include a graphical user interface and a set of input tools to facilitate the simulation of space missions in terms of nominal radiation models and mission trajectory profiles. The goal of this project is to produce a code that is considerably more accurate and user-friendly than existing Monte-Carlo-based tools for the evaluation of the space radiation environment. Furthermore, the code will be an essential complement to the currently existing analytic codes in the BRYNTRN/HZETRN family for the evaluation of radiation shielding. The code will be directly applicable to the simulation of environments in low earth orbit, on the lunar surface, on planetary surfaces (including the Earth) and in the interplanetary medium such as on a transit to Mars (and even in the interstellar medium). The software will include modules whose underlying physics base can continue to be enhanced and updated for physics content, as future data become available beyond the timeframe of the initial development now foreseen. This future maintenance will be available from the authors of FLUKA as part of their continuing efforts to support the users of the FLUKA code within the particle physics community. In keeping with the spirit of developing an evolving physics code, we are planning as part of this project, to participate in the efforts to validate the core FLUKA physics in ground-based accelerator test runs. The emphasis of these test runs will be the physics of greatest interest in the simulation of the space radiation environment. Such a tool will be of great value to planners, designers and operators of future space missions, as well as for the design of the vehicles and habitats to be used on such missions. It will also be of aid to future experiments of various kinds that may be affected at some level by the ambient radiation environment, or in the analysis of hybrid experiment designs that have been discussed for space-based astronomy and astrophysics. The tool will be of value to the Life Sciences personnel involved in the prediction and measurement of radiation doses experienced by the crewmembers on such missions. In addition, the tool will be of great use to the planners of experiments to measure and evaluate the space radiation environment itself. It can likewise be useful in the analysis of safe havens, hazard migration plans, and NASA's call for new research in composites and to NASA engineers modeling the radiation exposure of electronic circuits. This code will provide an important complimentary check on the predictions of analytic codes such as BRYNTRN/HZETRN that are presently used for many similar applications, and which have shortcomings that are more easily overcome with Monte Carlo type simulations. Finally, it is acknowledged that there are similar efforts based around the use of the GEANT4 Monte-Carlo transport code currently under development at CERN. It is our intention to make our software modular and sufficiently flexible to allow the parallel use of either FLUKA or GEANT4 as the physics transport engine.
    Schlagwort(e): Computer Programming and Software
    Materialart: Microgravity Materials Science Conference 2000; Volume 2; 465-470; NASA/CP-2000-210827/VOL2
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  • 82
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    In:  CASI
    Publikationsdatum: 2017-09-27
    Beschreibung: Historically NASA has trained teams of astronauts by bringing them to the Johnson Space Center in Houston to undergo generic training, followed by mission-specific training. This latter training begins after a crew has been selected for a mission (perhaps two years before the launch of that mission). While some Space Shuttle flights have included an astronaut from a foreign country, the International Space Station will be consistently crewed by teams comprised of astronauts from two or more of the partner nations. The cost of training these international teams continues to grow in both monetary and personal terms. Thus, NASA has been seeking alternative training approaches for the International Space Station program. Since 1994 we have been developing, testing, and refining shared virtual environments for astronaut team training, including the use of virtual environments for use while in or in transit to the task location. In parallel with this effort, we have also been preparing applications for training teams of military personnel engaged in peacekeeping missions. This paper will describe the applications developed to date, some of the technological challenges that have been overcome in their development, and the research performed to guide the development and to measure the efficacy of these shared environments as training tools.
    Schlagwort(e): Computer Programming and Software
    Materialart: The Capability of Virtual Reality to Meet Military Requirements; 22-1 - 22-6; RTO-MP-54
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  • 83
    Publikationsdatum: 2017-09-27
    Beschreibung: One of the critical phases in the development of a spacecraft attitude control system (ACS) is the testing of its flight software. The testing (and test verification) of ACS flight software requires a mix of skills involving software, knowledge of attitude control, and attitude control hardware, data manipulation, and analysis. The process of analyzing and verifying flight software test results often creates a bottleneck which dictates the speed at which flight software verification can be conducted. In the development of the Microwave Anisotropy Probe (MAP) spacecraft ACS subsystem, an integrated design environment was used that included a MAP high fidelity (HiFi) simulation, a central database of spacecraft parameters, a script language for numeric and string processing, and plotting capability. In this integrated environment, it was possible to automate many of the steps involved in flight software testing, making the entire process more efficient and thorough than on previous missions. In this paper, we will compare the testing process used on MAP to that used on other missions. The software tools that were developed to automate testing and test verification will be discussed, including the ability to import and process test data, synchronize test data and automatically generate HiFi script files used for test verification, and an automated capability for generating comparison plots. A summary of the benefits of applying these test methods on MAP will be given. Finally, the paper will conclude with a discussion of re-use of the tools and techniques presented, and the ongoing effort to apply them to flight software testing of the Triana spacecraft ACS subsystem.
    Schlagwort(e): Computer Programming and Software
    Materialart: 2001 Flight Mechanics Symposium; 295-309; NASA/CP-2001-209986
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  • 84
    Publikationsdatum: 2017-09-27
    Beschreibung: An integrally stiffened graphite/epoxy composite rotorcraft structure is evaluated via computational simulation. A computer code that scales up constituent micromechanics level material properties to the structure level and accounts for all possible failure modes is used for the simulation of composite degradation under loading. Damage initiation, growth, accumulation, and propagation to fracture are included in the simulation. Design implications with regard to defect and damage tolerance of integrally stiffened composite structures are examined. A procedure is outlined regarding the use of this type of information for setting quality acceptance criteria, design allowables, damage tolerance, and retirement-for-cause criteria.
    Schlagwort(e): Computer Programming and Software
    Materialart: Application of Damage Tolerance Principles for Improved Airworthiness of Rotorcraft; 12 - 1 - 12 - 13; RTO-MP-24
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  • 85
    Publikationsdatum: 2017-10-04
    Beschreibung: Parallelized versions of genetic algorithms (GAs) are popular primarily for three reasons: the GA is an inherently parallel algorithm, typical GA applications are very compute intensive, and powerful computing platforms, especially Beowulf-style computing clusters, are becoming more affordable and easier to implement. In addition, the low communication bandwidth required allows the use of inexpensive networking hardware such as standard office ethernet. In this paper we describe a parallel GA and its use in automated high-level circuit design. Genetic algorithms are a type of trial-and-error search technique that are guided by principles of Darwinian evolution. Just as the genetic material of two living organisms can intermix to produce offspring that are better adapted to their environment, GAs expose genetic material, frequently strings of 1s and Os, to the forces of artificial evolution: selection, mutation, recombination, etc. GAs start with a pool of randomly-generated candidate solutions which are then tested and scored with respect to their utility. Solutions are then bred by probabilistically selecting high quality parents and recombining their genetic representations to produce offspring solutions. Offspring are typically subjected to a small amount of random mutation. After a pool of offspring is produced, this process iterates until a satisfactory solution is found or an iteration limit is reached. Genetic algorithms have been applied to a wide variety of problems in many fields, including chemistry, biology, and many engineering disciplines. There are many styles of parallelism used in implementing parallel GAs. One such method is called the master-slave or processor farm approach. In this technique, slave nodes are used solely to compute fitness evaluations (the most time consuming part). The master processor collects fitness scores from the nodes and performs the genetic operators (selection, reproduction, variation, etc.). Because of dependency issues in the GA, it is possible to have idle processors. However, as long as the load at each processing node is similar, the processors are kept busy nearly all of the time. In applying GAs to circuit design, a suitable genetic representation 'is that of a circuit-construction program. We discuss one such circuit-construction programming language and show how evolution can generate useful analog circuit designs. This language has the desirable property that virtually all sets of combinations of primitives result in valid circuit graphs. Our system allows circuit size (number of devices), circuit topology, and device values to be evolved. Using a parallel genetic algorithm and circuit simulation software, we present experimental results as applied to three analog filter and two amplifier design tasks. For example, a figure shows an 85 dB amplifier design evolved by our system, and another figure shows the performance of that circuit (gain and frequency response). In all tasks, our system is able to generate circuits that achieve the target specifications.
    Schlagwort(e): Computer Programming and Software
    Materialart: Welcome to the NASA High Performance Computing and Communications Computational Aerosciences (CAS) Workshop 2000; D-000001
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  • 86
    Publikationsdatum: 2017-10-04
    Beschreibung: Within NASA's High Performance Computing and Communication (HPCC) program, the NASA Glenn Research Center is developing an environment for the analysis/design of aircraft engines called the Numerical Propulsion System Simulation (NPSS). The vision for NPSS is to create a "numerical test cell" enabling full engine simulations overnight on cost-effective computing platforms. To this end, NPSS integrates multiple disciplines such as aerodynamics, structures, and heat transfer and supports "numerical zooming" between O-dimensional to 1-, 2-, and 3-dimensional component engine codes. In order to facilitate the timely and cost-effective capture of complex physical processes, NPSS uses object-oriented technologies such as C++ objects to encapsulate individual engine components and CORBA ORBs for object communication and deployment across heterogeneous computing platforms. Recently, the HPCC program has initiated a concept called the Information Power Grid (IPG), a virtual computing environment that integrates computers and other resources at different sites. IPG implements a range of Grid services such as resource discovery, scheduling, security, instrumentation, and data access, many of which are provided by the Globus toolkit. IPG facilities have the potential to benefit NPSS considerably. For example, NPSS should in principle be able to use Grid services to discover dynamically and then co-schedule the resources required for a particular engine simulation, rather than relying on manual placement of ORBs as at present. Grid services can also be used to initiate simulation components on parallel computers (MPPs) and to address inter-site security issues that currently hinder the coupling of components across multiple sites. These considerations led NASA Glenn and Globus project personnel to formulate a collaborative project designed to evaluate whether and how benefits such as those just listed can be achieved in practice. This project involves firstly development of the basic techniques required to achieve co-existence of commodity object technologies and Grid technologies; and secondly the evaluation of these techniques in the context of NPSS-oriented challenge problems. The work on basic techniques seeks to understand how "commodity" technologies (CORBA, DCOM, Excel, etc.) can be used in concert with specialized "Grid" technologies (for security, MPP scheduling, etc.). In principle, this coordinated use should be straightforward because of the Globus and IPG philosophy of providing low-level Grid mechanisms that can be used to implement a wide variety of application-level programming models. (Globus technologies have previously been used to implement Grid-enabled message-passing libraries, collaborative environments, and parameter study tools, among others.) Results obtained to date are encouraging: we have successfully demonstrated a CORBA to Globus resource manager gateway that allows the use of CORBA RPCs to control submission and execution of programs on workstations and MPPs; a gateway from the CORBA Trader service to the Grid information service; and a preliminary integration of CORBA and Grid security mechanisms. The two challenge problems that we consider are the following: 1) Desktop-controlled parameter study. Here, an Excel spreadsheet is used to define and control a CFD parameter study, via a CORBA interface to a high throughput broker that runs individual cases on different IPG resources. 2) Aviation safety. Here, about 100 near real time jobs running NPSS need to be submitted, run and data returned in near real time. Evaluation will address such issues as time to port, execution time, potential scalability of simulation, and reliability of resources. The full paper will present the following information: 1. A detailed analysis of the requirements that NPSS applications place on IPG. 2. A description of the techniques used to meet these requirements via the coordinated use of CORBA and Globus. 3. A description of results obtained to date in the first two challenge problems.
    Schlagwort(e): Computer Programming and Software
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  • 87
    facet.materialart.
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    In:  CASI
    Publikationsdatum: 2017-10-04
    Beschreibung: The solution data computed from large scale simulations are sometimes too big for main memory, for local disks, and possibly even for a remote storage disk, creating tremendous processing time as well as technical difficulties in analyzing the data. The excessive storage demands a corresponding huge penalty in I/O time, rendering time and transmission time between different computer systems. In this paper, a multiresolution scheme is proposed to compress field simulation or experimental data without much loss of important information in the representation. Originally, the wavelet based multiresolution scheme was introduced in image processing, for the purposes of data compression and feature extraction. Unlike photographic image data which has rather simple settings, computational field simulation data needs more careful treatment in applying the multiresolution technique. While the image data sits on a regular spaced grid, the simulation data usually resides on a structured curvilinear grid or unstructured grid. In addition to the irregularity in grid spacing, the other difficulty is that the solutions consist of vectors instead of scalar values. The data characteristics demand more restrictive conditions. In general, the photographic images have very little inherent smoothness with discontinuities almost everywhere. On the other hand, the numerical solutions have smoothness almost everywhere and discontinuities in local areas (shock, vortices, and shear layers). The wavelet bases should be amenable to the solution of the problem at hand and applicable to constraints such as numerical accuracy and boundary conditions. In choosing a suitable wavelet basis for simulation data among a variety of wavelet families, the supercompact wavelets designed by Beam and Warming provide one of the most effective multiresolution schemes. Supercompact multi-wavelets retain the compactness of Haar wavelets, are piecewise polynomial and orthogonal, and can have arbitrary order of approximation. The advantages of the multiresolution algorithm are that no special treatment is required at the boundaries of the interval, and that the application to functions which are only piecewise continuous (internal boundaries) can be efficiently implemented. In this presentation, Beam's supercompact wavelets are generalized to higher dimensions using multidimensional scaling and wavelet functions rather than alternating the directions as in the 1D version. As a demonstration of actual 3D data compression, supercompact wavelet transforms are applied to a 3D data set for wing tip vortex flow solutions (2.5 million grid points). It is shown that high data compression ratio can be achieved (around 50:1 ratio) in both vector and scalar data set.
    Schlagwort(e): Computer Programming and Software
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  • 88
    Publikationsdatum: 2017-10-02
    Beschreibung: The mission of this research is to be world-class creators and facilitators of innovative, intelligent, high performance, reliable information technologies that enable NASA missions to (1) increase software safety and quality through error avoidance, early detection and resolution of errors, by utilizing and applying empirically based software engineering best practices; (2) ensure customer software risks are identified and/or that requirements are met and/or exceeded; (3) research, develop, apply, verify, and publish software technologies for competitive advantage and the advancement of science; and (4) facilitate the transfer of science and engineering data, methods, and practices to NASA, educational institutions, state agencies, and commercial organizations. The goals are to become a national Center Of Excellence (COE) in software and system independent verification and validation, and to become an international leading force in the field of software engineering for improving the safety, quality, reliability, and cost performance of software systems. This project addresses the following problems: Ensure safety of NASA missions, ensure requirements are met, minimize programmatic and technological risks of software development and operations, improve software quality, reduce costs and time to delivery, and improve the science of software engineering
    Schlagwort(e): Computer Programming and Software
    Materialart: Proceedings of the Twenty-Fourth Annual Software Engineering Workshop; NASA/CP-2000-209890
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  • 89
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    In:  CASI
    Publikationsdatum: 2017-10-02
    Beschreibung: This paper discusses the following topics: (1) Autonomy for Future Missions- Mars Outposts, Titan Aerobot, and Europa Cryobot / Hydrobot; (2) Emergence of Autonomy- Remote Agent Architecture, Closing Loops Onboard, and New Millennium Flight Experiment; and (3) Software Engineering Challenges- Influence of Remote Agent, Scalable Autonomy, Autonomy Software Validation, Analytic Verification Technology, and Autonomy and Software Software Engineering.
    Schlagwort(e): Computer Programming and Software
    Materialart: Proceedings of the Twenty-Fourth Annual Software Engineering Workshop; NASA/CP-2000-209890
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  • 90
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    Unbekannt
    In:  CASI
    Publikationsdatum: 2017-10-02
    Beschreibung: Software testing is a well-defined phase of the software development life cycle. Functional ("black box") testing and structural ("white box") testing are two methods of test case design commonly used by software developers. A lesser known testing method is risk-based testing, which takes into account the probability of failure of a portion of code as determined by its complexity. For object oriented programs, a methodology is proposed for identification of risk-prone classes. Risk-based testing is a highly effective testing technique that can be used to find and fix the most important problems as quickly as possible.
    Schlagwort(e): Computer Programming and Software
    Materialart: Proceedings of the Twenty-Fourth Annual Software Engineering Workshop; NASA/CP-2000-209890
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  • 91
    Publikationsdatum: 2017-10-02
    Beschreibung: This paper contains the following sections: GSFC Space Missions of the 21st Century, Information Technology Challenges, Components of a GSFC Solution, and Conclusions.
    Schlagwort(e): Computer Programming and Software
    Materialart: Proceedings of the Twenty-Fourth Annual Software Engineering Workshop; NASA/CP-2000-209890
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  • 92
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    In:  CASI
    Publikationsdatum: 2018-06-09
    Beschreibung: Marketed as the "Software of the Future," Optimal Engineering Systems P.I. EXPERT(TM) technology offers statistical process control and optimization techniques that are critical to businesses looking to restructure or accelerate operations in order to gain a competitive edge. Kennedy Space Center granted Optimal Engineering Systems the funding and aid necessary to develop a prototype of the process monitoring and improvement software. Completion of this prototype demonstrated that it was possible to integrate traditional statistical quality assurance tools with robust optimization techniques in a user- friendly format that is visually compelling. Using an expert system knowledge base, the software allows the user to determine objectives, capture constraints and out-of-control processes, predict results, and compute optimal process settings.
    Schlagwort(e): Computer Programming and Software
    Materialart: Spinoff 2002; 114-115; NASA/NP-2002-09-290-HQ
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  • 93
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    Unbekannt
    In:  CASI
    Publikationsdatum: 2018-06-09
    Beschreibung: GridPro is an automatic, object-oriented, multi-block grid generator that provides ease of use, high quality, rapid production, and parametric design. When paired with a 3-D graphic user interface called az- Manager, GridPro presents users with an extremely efficient, interactive capability to build topology, edit surfaces, set computational fluid dynamics (CFD) boundary conditions, and view multi-block grids. The origins of the GridPro technology date back to a 1989 SBIR contract with NASA's Glenn Research Center, in which Glenn was seeking a multi-block grid generation program that would run automatically upon identifying a pattern of grid blocks supplied by a user. The technology is currently used in many engineering fields, including aerospace, turbo- machinery, automotive, and chemical industries.
    Schlagwort(e): Computer Programming and Software
    Materialart: Spinoff 2002; 118-119; NASA/NP-2002-09-290-HQ
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  • 94
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    In:  CASI
    Publikationsdatum: 2018-06-09
    Beschreibung: NASA's need to trace mistakes to their source to try and eliminate them in the future has resulted in software known as Root Cause Analysis (RoCA). Fair, Isaac & Co., Inc. has applied RoCA software, originally developed under an SBIR contract with Kennedy, to its predictive software technology. RoCA can generate graphic reports to make analysis of problems easier and more efficient.
    Schlagwort(e): Computer Programming and Software
    Materialart: Spinoff 2000; 65; NASA/NP-2000-08-257-HQ
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  • 95
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    Unbekannt
    In:  CASI
    Publikationsdatum: 2018-06-09
    Beschreibung: AgentBuilder is a software component developed under an SBIR contract between Reticular Systems, Inc., and Goddard Space Flight Center. AgentBuilder allows software developers without experience in intelligent agent technologies to easily build software applications using intelligent agents. Agents are components of software that will perform tasks automatically, with no intervention or command from a user. AgentBuilder reduces the time and cost of developing agent systems and provides a simple mechanism for implementing high-performance agent systems.
    Schlagwort(e): Computer Programming and Software
    Materialart: Spinoff 2000; 59; NASA/NP-2000-08-257-HQ
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  • 96
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    In:  CASI
    Publikationsdatum: 2018-06-09
    Beschreibung: Qualtech Systems, Inc. developed a complete software system with capabilities of multisignal modeling, diagnostic analysis, run-time diagnostic operations, and intelligent interactive reasoners. Commercially available as the TEAMS (Testability Engineering and Maintenance System) tool set, the software can be used to reveal unanticipated system failures. The TEAMS software package is broken down into four companion tools: TEAMS-RT, TEAMATE, TEAMS-KB, and TEAMS-RDS. TEAMS-RT identifies good, bad, and suspect components in the system in real-time. It reports system health results from onboard tests, and detects and isolates failures within the system, allowing for rapid fault isolation. TEAMATE takes over from where TEAMS-RT left off by intelligently guiding the maintenance technician through the troubleshooting procedure, repair actions, and operational checkout. TEAMS-KB serves as a model management and collection tool. TEAMS-RDS (TEAMS-Remote Diagnostic Server) has the ability to continuously assess a system and isolate any failure in that system or its components, in real time. RDS incorporates TEAMS-RT, TEAMATE, and TEAMS-KB in a large-scale server architecture capable of providing advanced diagnostic and maintenance functions over a network, such as the Internet, with a web browser user interface.
    Schlagwort(e): Computer Programming and Software
    Materialart: Spinoff 2001: Special Millennium Feature; 94-95; NASA/NP-2001-04-264-HQ
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  • 97
    Publikationsdatum: 2018-06-08
    Schlagwort(e): Computer Programming and Software
    Materialart: 16th International Symposium on Space Flight Dynamics; Pasadena, CA; United States
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  • 98
    Publikationsdatum: 2018-06-08
    Beschreibung: The 2nd GSFC-JPL QMSW workshop brought together 56 participants mostly from GSFC and JPL to focus on critical challenges for mission software.
    Schlagwort(e): Computer Programming and Software
    Materialart: Quality Mission Software (QMSW) Workshop; Fallbrook, CA; United States
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  • 99
    Publikationsdatum: 2018-06-08
    Beschreibung: In this paper, we will summarize the software trends and their impact on the cost of developing flight and ground software.
    Schlagwort(e): Computer Programming and Software
    Materialart: SPACE 2003; Long Beach, CA; United States
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  • 100
    Publikationsdatum: 2018-06-08
    Schlagwort(e): Computer Programming and Software
    Materialart: Seminar at CACR, Caltech; Pasadena, CA; United States
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