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Sample records for dem einfluss verschiedener

  1. Untersuchungen zum Einfluss verschiedener Dosierungsintervalle von Dorzolamid, Dorzolamid-Timolol und Latanoprost auf den Intraokulardruck normotensiver Hunde

    OpenAIRE

    Schönfelder, Ralph

    2010-01-01

    Ralph Schönfelder Untersuchungen zum Einfluss verschiedener Dosierungsintervalle von Dorzolamid, Dorzolamid-Timolol und Latanoprost auf den Intraokulardruck normotensiver Hunde Klinik für Kleintiere, Veterinärmedizinische Fakultät der Universität Leipzig Eingereicht im März 2010 Bibliografische Angaben: 93 S., 27 Abb., 14 Tab., 224 Lit., Anhang mit 2 Abb., 4 Tab. Schlüsselwörter: Glaukom, Intraokulardruck, Prostaglandine, Karboanhydrasehemmer, Timolol, Hund Das Glau...

  2. Einsatz von modifizierten Rundtränken als tiergerechte Wasserversorgung für Pekingmastenten unter Praxisbedingungen und ihr Einfluss auf Tierhygiene und verschiedene Gesundheitsparameter

    OpenAIRE

    Hirsch, Nicola

    2011-01-01

    Der Ständige Ausschuss des Europäischen Übereinkommens zum Schutz von Tieren in landwirtschaftlicher Tierhaltung fordert in seinen Empfehlungen in Bezug auf Pekingenten (1999), dass Enten, sofern sie keinen Zugang zu Badewasser haben, mit solchen Wasservorrichtungen ausreichend versorgt werden müssen, die es ihnen ermöglichen, mit dem Schnabel Wasser aufzunehmen, den Kopf mit Wasser zu bedecken und sich problemlos Wasser über den Körper zu schütten. Ferner sollten sie die Möglichkeit haben, i...

  3. [Dimitri Steinke: Die Zivilrechtsordnungen des Baltikums unter dem Einfluss ausländischer, insbesondere deutscher Rechtsquellen. (Osnabrücker Schriften zur Rechtsgeschichte, Bd. 16.) V&R unipress. Göttingen 2009. 243 S. ISBN 978-3-89971-573-6] / M

    Index Scriptorium Estoniae

    Luts-Sootak, Marju, 1966-

    2011-01-01

    Arvustus: Dimitri Steinke. Die Zivilrechtsordnungen des Baltikums unter dem Einfluss ausländischer, insbesondere deutscher Rechtsquellen. (Osnabrücker Schriften zur Rechtsgeschichte ; 16). Göttingen, 2009

  4. [Dimitri Steinke: Die Zivilrechtsordnungen des Baltikums unter dem Einfluss ausländischer, insbesondere deutscher Rechtsquellen. (Osnabrücker Schriften zur Rechtsgeschichte, Bd. 16.) V&R unipress. Göttingen 2009. 243 S. ISBN 978-3-89971-573-6] / M

    Index Scriptorium Estoniae

    Luts-Sootak, Marju, 1966-

    2011-01-01

    Arvustus: Dimitri Steinke. Die Zivilrechtsordnungen des Baltikums unter dem Einfluss ausländischer, insbesondere deutscher Rechtsquellen. (Osnabrücker Schriften zur Rechtsgeschichte ; 16). Göttingen, 2009

  5. The Growing Influence of Al-Qaeda on the African Continent Der wachsende Einfluss von Al-Qaida auf dem afrikanischen Kontinent

    Directory of Open Access Journals (Sweden)

    Hans Krech

    2011-01-01

    Full Text Available Al-Qaeda’s influence in Africa is growing. From 2009 to 2011, activity by Al-Qaeda was noted in 19 African nations and regions. Four regional Al-Qaeda organizations operate on the continent, which in turn often have several sub-organizations: the Egyptian Islamic Jihad, the Libyan Islamic Fighting Group, Al-Qaeda in the Islamic Maghreb (with its suborganizations Al-Qaeda in Mali, Al-Qaeda in Mauritania, Al-Qaeda in Morocco and Al-Qaeda in Sudan and Al-Shabab in Somalia. Since Osama bin Laden’s death on 2 May 2011, the influence of African leaders within Al-Qaeda has increased significantly. All three presumed members of the strategic command level originate from Africa. The revolutions of the Arab Spring have not harmed Al-Qaeda. This contribution highlights the potential for further expansion by Al-Qaeda on the African continent, and how this needs to be responded to.Der Einfluss von Al-Qaida in Afrika wächst. In den Jahren 2009 bis 2011 wurden Al-Qaida-Aktivitäten in 19 afrikanischen Staaten und Gebieten registriert. In Afrika gibt es vier Al-Qaida-Regionalorganisationen, die wiederum oft mehrere Unterorganisationen haben: Ägyptischer Islamischer Jihad (EIJ, Libysch-Islamische Kampfgruppe (LIFG, Al-Qaida im Islamischen Maghreb (AQIM, mit den Unterorganisationen Al-Qaida im Sudan, Al-Qaida in Mali, Al-Qaida in Marokko, Al-Qaida in Mauretanien sowie die Al-Shabab in Somalia. Nach dem Tod von Osama bin Laden am 2. Mai 2011 ist der Einfluss von afrikanischen Führern in der Al-Qaida deutlich angewachsen. Alle drei mutmaßlichen Mitglieder der strategischen Führungsebene kommen aus Afrika. Die Revolutionen des “Arabischen Frühlings” haben Al-Qaida nicht geschadet. Diese Entwicklungen könnten zu einer weiteren Ausbreitung von Al-Qaida auf dem Afrikanischen Kontinent beitragen.

  6. Influence of combustion air guidance on solid matter burnout and on pollutant emissions in grid incinerators; Einfluss der Verbrennungsluftfuehrung auf den Feststoffabbrand und auf das Schadstoffverhalten bei der Hausmuellverbrennung auf dem Rost

    Energy Technology Data Exchange (ETDEWEB)

    Hunsinger, H.; Seifert, H. [Forschungszentrum Karlsruhe GmbH Technik und Umwelt (Germany). Inst. fuer Technische Chemie

    2003-07-01

    The contribution investigates the influence of combustion air guidance strategies on process optimisation. In particular, it is investigated if efficient burnout correlates with low pollutant emissions and if the effects are similar or contrary for the different process goals. (orig.) [German] Der Einfluss von Brennstoffqualitaeten, der Ofengeometrie sowie von Feuerungsbetriebsparametern auf die Bildungsraten von Schadstoffen wie PCDD/F und NO{sub x} und auf die Transferraten von Schwermetallen, Chlor- und Schwefelverbindungen aus dem Brennstoffbett ins Rauchgas ist zur Zeit nur ungenuegend bekannt. Besonders die Frage, wie die primaere Forderung nach moeglichst vollstaendigem Ausbrand von Rauchgas und Rostasche mit weiteren Zielen wie niedrige Bildungsraten von Schadstoffen und Inertisierung der Rostasche korreliert, zeigt den Bedarf umfassender systematischer Untersuchungen auf. Im Rahmen dieses Beitrags soll als Beispiel fuer Modifikationen des Verbrennungsprozesses der Einfluss unterschiedlicher Verbrennungsluftfuehrungen auf die aufgefuehrten Optimierungsziele vorgestellt werden. Insbesondere soll der Frage nachgegangen werden, ob ein effizienter Ausbrand mit niedrigen Schadstoffbildungsraten korreliert und ob zwischen den Zielgroessen gleiche oder kontraere Wirkungen auftreten. (orig.)

  7. Influence of tensides and lipophilic substrates on the biological availability of polycyclic aromatic hydrocarbons (PAHs); Ueber dem Einfluss von Tensiden und lipophilen Substraten auf die Bioverfuegbarkeit von polyzyklischen aromatischen Kohlenwasserstoffen (PAK)

    Energy Technology Data Exchange (ETDEWEB)

    Soeder, C.J. von; Kleespies, M.; Eschner, C.; Webb, L.; Groeneweg, J. [Forschungszentrum Juelich GmbH (Germany). IBT-3/ICG-6

    1997-12-31

    The objects of the study were as follows: isolation and characterization of PAH-degrading micro-organisms from lysimeters; tests relating to the experimental simulation of the conditions permitting pollutant degradation in soil; investigation of the influence of tensides and other dissolved organic compounds on the biological availability and degradation of PAHs. (orig./SR) [Deutsch] - Isolierung und Charakterisierung PAK-abbauender Mikroorganismen aus Lysimetern; Versuche zur experimentellen Simulation der Bedingungen, unter denen der Abbau von Schadstoffen im Boden erfolgt. - Untersuchung des Einflusses von Tensiden und anderen geloesten organischen Verbindungen auf Bioverfuegbarkeit und Abbau von PAK. (orig./SR)

  8. Die Übertragungsgenauigkeit von okklusalen Verhältnissen in den Artikulator durch verschiedene Registriermaterialien

    OpenAIRE

    Jansen, Stephan

    2007-01-01

    Im Rahmen der vorliegenden Untersuchung wurden verschiedene Registriermaterialien auf ihre Übertragungsgenauigkeit beziehungsweise Eignung in bezug auf eine Reproduktion von Kieferrelationsverhältnissen bei voll bezahnten Modellen geprüft. In einem ersten Versuchsteil wurden die verschiedenen Registriermaterialien (neben Wachsen und dem Abformgips außerdem Elastomere, und zwar bis auf Ramitec Penta® [einer Polyether-Bißregistrierpaste] ausschließlich schnellanbindende additionsvernetzende ...

  9. Einfluss der geometrischen Kengrössen im Wiederstandsbuckelschweissen verschiedener Materialkombinationen

    DEFF Research Database (Denmark)

    Kristensen, Lars; Zhang, Wenqi; Bay, Niels

    2000-01-01

    to show the temperature distribution using the different geometric parameters. The numerical simulations with SORPAS can explain the differences in the welding lobes and bond strength. This shows SORPAS as a strong tool in the product development of workpieces for resistance projection welding. Based......Resistance projection welding is widely used for joining of workpieces with almost any geometric combination. This makes standardization of projection welding impossible. In order to facilitate industrial applications of projection welding, systematic investigations are carried out on the geometric...... parameters by numerical modeling and experimental studies. SORPAS, an FEM program for numerical modeling of resistance welding, is developed as a tool to help in the phase of product design and process optimization in both spot and projection welding. A systematic experimental investigation of projection...

  10. Zum Einfluss von Alter, Beruf, Diagnose und Geschlecht auf den VHI-12

    OpenAIRE

    Gonnermann, U; Nawka, T

    2008-01-01

    Einleitung: Die Übertragung des VHI in eine einheitliche deutsche Konsensfassung erfolgte 2003; eine verkürzte Version des Fragebogens mit 12 Items (VHI-12) wurde nach Faktorenanalyse erstellt. Für die praktische Anwendung können die Summenwerte des VHI-12 in Schweregrade klassifiziert werden. In der vorliegenden Studie soll der Einfluss der Determinanten Alter, Beruf, Diagnose und Geschlecht auf den VHI-12 geprüft werden. Material und Methoden: Mit dem VHI-12 wurden 495 Patienten (30%...

  11. Influence of different etchants on the representation of microstructures in nickel alloys; Einfluss verschiedener Aetzmittel auf die Gefuegedarstellung in Nickellegierungen

    Energy Technology Data Exchange (ETDEWEB)

    Speicher, Magdalena; Scheck, Rudi; Maile, Karl [Stuttgart Univ. (Germany). Materialpruefungsanstalt

    2016-04-15

    This work presents a comparison of selected nickel alloys of the same condition which were treated by means of specifically chosen etching techniques. Microstructures on microscope images of wrought Alloy 617, a casting variant of Alloy 625, a polycrystalline casting alloy IN-738 LC, as well as of a monocrystalline superalloy CM 247 LC SX, respectively, are juxtaposed and evaluated. This approach allows for a comprehensive optical microscopy characterization of the characteristic microstructural features.

  12. Particle Reduction Strategies - PAREST. Influence of the boundary conditions from the global chemistry transport model TM5 on the regional aerosol chemistry transport model REM CALGRID; Strategien zur Verminderung der Feinstaubbelastung - PAREST. Einfluss der Randbedingungen aus dem globalen Chemie-Transport-Modell TM5 auf das regionale Aerosol-Chemie-Transport-Modell REM-CALGRID. Teilbericht

    Energy Technology Data Exchange (ETDEWEB)

    Kerschbaumer, Andreas; Hannig, Katrin [Freie Univ. Berlin (Germany). Inst. fuer Meteorologie, Troposphaerische Umweltforschung

    2013-06-15

    In this report the coupling of a global model is presented with a continental model. It examines how far the forecasts of regional air quality in Europe are affected by the choice of boundary conditions. The focus of this report is to analyze the influence of different boundary conditions on the calculated soil concentrations of ozone and PM10. A model evaluation, however, was not the aim of this study. [German] In diesem Bericht wird die Koppelung eines Globalmodells mit einem kontinentalen Modell vorgestellt. Es wird untersucht, wie weit die Prognosen der regionalen Luftqualitaet in Europa von der Wahl der Randbedingungen beeinflusst werden. Der Schwerpunkt des vorliegenden Berichts liegt in der Analyse des Einflusses der verschiedenen Randbedingungen auf die berechneten Bodenkonzentrationen von Ozon und PM10. Eine Modellevaluierung hingegen war nicht Ziel dieser Studie.

  13. ElevationDEM_DEM1M2005

    Data.gov (United States)

    Vermont Center for Geographic Information — This metadata applies to the following collection area(s): Essex County 2005 1m and Digital Elevation Model (DEM) datasets of various "hydro-treatments": DEM, DEMHF...

  14. ElevationDEM_DEM2M

    Data.gov (United States)

    Vermont Center for Geographic Information — This metadata applies to the following collection area(s): Bennington County 2012 2.0m and Digital Elevation Model (DEM) datasets of various "hydro-treatments": DEM,...

  15. ElevationDEM_DEM1M2009

    Data.gov (United States)

    Vermont Center for Geographic Information — This metadata applies to the following collection area(s): Essex County 2005 1m and Digital Elevation Model (DEM) datasets of various "hydro-treatments": DEM, DEMHF...

  16. ElevationDEM_DEM1M2010

    Data.gov (United States)

    Vermont Center for Geographic Information — This metadata applies to the following collection area(s): Essex County 2005 1m and Digital Elevation Model (DEM) datasets of various "hydro-treatments": DEM, DEMHF...

  17. ElevationDEM_DEM1M2007

    Data.gov (United States)

    Vermont Center for Geographic Information — This metadata applies to the following collection area(s): Essex County 2005 1m and Digital Elevation Model (DEM) datasets of various "hydro-treatments": DEM, DEMHF...

  18. Endometriosezentren verschiedener Stufen zur Verbesserung der medizinischen Versorgungsqualität, der Forschung sowie der ärztlichen Fort- und Weiterbildung

    Directory of Open Access Journals (Sweden)

    Ebert AD

    2008-01-01

    Full Text Available In Europa wird die Idee der Qualitätsverbesserung auf dem Gebiet der Endometriose vertieft. Verschiedene "Task Forces" arbeiten mit zum Teil identischen Methoden am gleichen Ziel. Die Bildung spezialisierter Endometriosezentren verbunden mit einer breiten Qualifikation der Ärzte und des medizinischen Personals gehören – begleitet von der Unterstützung der Forschung – ebenso in dieses Spektrum wie die Schulung und Information der betroffenen Frauen sowie die Sensibilisierung der Gesundheitspolitik, der Kostenträger und der Industrie. Vor dem Hintergrund knapper Ressourcen ist eine Bündelung des vorhandenen nationalen und internationalen Engagements absehbar und notwendig. Inwieweit dies zur konsequenten Gründung von einheitlichen nationalen Endometriose-Gruppen als Basis einer europäischen Dachgesellschaft führen könnte, bleibt abzuwarten. Wünschenswert ist es allemal.

  19. Veränderungen verschiedener Symptomenscores nach transurethraler Prostataresektion

    Directory of Open Access Journals (Sweden)

    Hakenberg OW

    1999-01-01

    Full Text Available Das Ziel der vorliegenden Arbeit war die Untersuchung der Aussagekraft verschiedener Symptomen- und Lebensqualitäts-Scores bei Patienten mit symptomatischer Prostatahyperplasie. Der Internationale Prostata-Symptomenscore mit Lebensqualitätsindex, der "Bother Score" der American Urological Association und der "Benign Prostatic Hyperplasia Impact Index" wurden benutzt, um Symptomenprofile von Patienten vor, sowie drei und sechs Monate nach transurethraler Prostataresektion (TURP zu erheben. Untersucht wurden 96 Patienten mit einem Durchschnittsalter von 69,9 Jahren, die zwischen Dezember 1996 und Dezember 1997 transurethral reseziert wurden. Der Durchschnittswert für das präoperativ sonographisch bestimmte Prostatavolumen betrug 50,2 ml, für das Resektionsgewicht 25,9 g, sowie für den maximalen Flow vor TURP 9,68 ml/Sek und 21,2 ml/Sek drei Monate postoperativ. Die statistische Analyse der Ergebnisse zeigte eine signifikante Verbesserung aller Symptomenscores 3 Monate nach TURP (p jeweils 0,001, und weitere signifikante Verbesserungen nach 6 Monaten (p 0,007 bis p 0,05. Alle zeitgleich erhobenen vier Symptomenscores korrelierten miteinander (Spearmans Korrelation, p 0,001 bis 0,002. Der präoperative IPSS-Wert zeigte eine hohe Sensitivität und Spezifität in der Vorhersage der postoperativen Verbesserung: positiver und negativer prädiktiver Wert bei einem IPSS-Grenzwert von 15 Punkten lagen bei 84 % bzw. 78,6 %. Somit zeigten alle vier Scores deutliche Verbesserungen nach TURP, wobei der IPSS bei hohem prädiktivem Aussagewert als Indikationsparameter für die TURP am geeignetsten erscheint, und die Verwendung zusätzlicher Lebensqualitäts-Scores damit keine Vorteile bringt.

  20. ElevationDEM_DEM1m

    Data.gov (United States)

    Vermont Center for Geographic Information — A "Bare Earth" Digital Elevation Model (DEM) data represents the bare ground surface without any objects like plants and buildings on it, was derived from the best...

  1. Detection of different hazards by means of mine surveying documents and mining charts. Erkennen verschiedener Gefahren aus dem Bergmaennischen Risswerk

    Energy Technology Data Exchange (ETDEWEB)

    Leonhardt, J. (Bergbau-Forschung GmbH - Forschungsinstitut des Steinkohlenbergbauvereins, Essen (Germany, F.R.). Hauptabteilung Markscheidewesen und Gebirgsschlagverhuetung)

    1989-05-01

    The author reports a development project annual at removing the factor of human failure in the detection of hazards as for as possible by rendering the detection process proper more objective. This concerns in particular, those hazards which cannot be detected immediately in the pit. For their detection, mine surveying documents and mining charts need to be consulted. The project looked into hazards which were grouped into hazards resulting from subterranean water, fire areas or from zones with increased pressure for which models were developed, EDP programmes produced and tested, and hazard detection criteria determined. The methodology for data acquisition from mining surveying documents was defined and tested under practical conditions. (MOS).

  2. Einfluss von Zidovudin und Zalcitabin auf die transkriptionelle Regulation verschiedener nukleär-kodierter mitochondrialer Proteine in einer Leberzellkarzinomzellreihe (Hep G2)

    OpenAIRE

    Danese, Giuseppe Daniele

    2014-01-01

    NRTI-UAWs werden durch mitochondriale Toxizität der NRTIs erklärt. In einer Proteomstudie zeigten sich nach AZT- o. ddC-Behandlung von Hep G2 Zellen nukleär-kodierte mitochondriale Proteine differentiell reguliert. Nach Herstellung theoretischer Zusammenhänge zwischen o.g. Proteinregulation u. NRTI-UAWs, wie Anämie, Myopathie, Laktatazidose u. PNP, wurde in dieser Arbeit die transkriptionelle Regulation von ALDOA, TUFM, PDHA1, MTHFD2, HSPE1 u. PARK7 via Real-Time-Quantitative-PCR ...

  3. Influence of various base oils on friction and power loss in gears; Einfluss verschiedener Grundoele auf Reibung und Verlustleistung in Zahnradgetrieben

    Energy Technology Data Exchange (ETDEWEB)

    Doleschel, A.; Michaelis, K.; Hoehn, B.R.

    2001-03-01

    The frictional behaviour of synthetic lubricants was systematically investigated in a twin disc test rig and a back-to-back gear test rig. For 22 lubricants (mineral oil, polyalfaolefin (PAO), polyglycol (PG), ester and mixtures) the coefficient of friction was measured in the twin disc test rig, dependant on pressure, oil temperature, rolling and sliding velocity. In the gear test rig pressure and velocity was varied for 9 lubricants. The mineral oil shows an estimated coefficient of friction of about {mu} >> 0.045, the synthetic lubricants have a lower coefficient of friction. In the twin disc test rig the lowest coefficient of friction with PG as low as 20% of the coefficient of mineral oil was measured, depending on the mixture of EO:PO. In the gear test rig such low coefficients of friction were not measured, but still values of 60% compared to mineral oil were obtained. Esters show in the twin disc test rig a coefficient of friction in the range of 30% to 100% of the coefficient of friction of mineral oil, in the gear test rig in the range of 60% to 100%. From these investigations a calculation method for the coefficient of friction in disc and gear contacts was derived. With these equations the power loss and efficiency of transmissions in practice, lubricated with synthetic gear oils can be evaluated. (orig.)

  4. NTHMP DEM Project

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's National Geophysical Data Center (NGDC) is building high-resolution digital elevation models (DEMs) to support individual coastal States as part of the...

  5. kawaihae_dem.grd

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NGDC builds and distributes high-resolution, coastal digital elevation models (DEMs) that integrate ocean bathymetry and land topography to support NOAA's mission to...

  6. NOAA VDatum DEM Project

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's National Geophysical Data Center (NGDC) is building high-resolution digital elevation models (DEMs) for select U.S. coastal regions in the Gulf of Mexico....

  7. Spielst du noch oder lernst du schon? Der Einfluss des Framings auf Unterhaltung und Inhaltsrezeption bei Game-based Learning

    Directory of Open Access Journals (Sweden)

    Ulrich Wechselberger

    2012-03-01

    Full Text Available Der Umgang mit Lernspielen kann entweder spielerische oder ernste Züge tragen. Dieser Beitrag fragt danach, inwiefern sich aus einer solchen Rahmung Konsequenzen für das pädagogische Potenzial von Game-based Learning ergeben. Es wurde vermutet, dass es gerade die Abgrenzung des Spiels zum Ernst des Alltags ist, die es so unterhaltsam und motivierend macht, dass andererseits aber die Scheinhaftigkeit des Spiels womöglich die Bereitschaft der Adressaten zur Übernahme der Lernspielinhalte in ihr Wissensrepertoire reduziert. Ein und dasselbe Lernspiel könnte somit, abhängig von der Definition der Situation, als mehr oder weniger unterhaltsam, aber komplementär auch als mehr oder weniger informativ erachtet werden. In einem experimentellen Setting mit Realschüler/innen der 8. Klasse (n = 54 wurden diese Hypothesen empirisch geprüft. Versuchspersonen aus zwei unabhängigen Stichproben bearbeiteten das gleiche Lernspiel, den einen wurde jedoch suggeriert, es handle sich um eine Lernsoftware für den Unterricht, den anderen, es sei ein reines Computerspiel für die Freizeit. Im Anschluss wurden per Fragebogen die Unterhaltung und die Bereitschaft zur Übernahme der Medieninhalte erfasst. Der Bezugsrahmen allein hatte zwar nicht den erwarteten unmittelbaren Einfluss auf Unterhaltung und Rezeptionsbereitschaft, es ergaben sich aber in deskriptiver und teils auch inferenzstatistischer Hinsicht Interaktionen mit dem Bezugsrahmen und dem Geschlecht der Versuchspersonen bzw. ihrer Präferenz für Lernspiele

  8. Untersuchungen zu den unmittelbaren Wirkungen verschiedener Dehnmethoden auf ausgewählte Kraftparameter

    OpenAIRE

    Höss-Jelten, Christine

    2007-01-01

    Anhand von 5 Untersuchungen mit insgesamt 64 Versuchspersonen (34 Mehrkämpfer, Springer und Werfer aus der Leichtathletik, 30 Sportstudenten) wurde der Frage nachgegangen, wie sich drei verschiedene Dehnmethoden im Rahmen des Aufwärmens auf unmittelbar anschließende Kraftleistungen auswirken. Es wurde jeweils ein Versuchsplan mit kompletter Messwiederholung konzipiert, d. h. alle Versuchspersonen wandten alle drei Dehnmethoden an unterschiedlichen Tagen an. Das Treatment umfasste 3 – 6 Dehnüb...

  9. Zur Optimierung der Kombinationsstrategie verschiedener Satellitenbeobachtungsverfahren bei der Realisierung eines globalen terrestrischen Referenzsystems

    OpenAIRE

    Glaser, Susanne

    2014-01-01

    Eine der zentralen Aufgaben der Geodäsie liegt in der Definition und der Realisierung von geeigneten Referenzsystemen. Die Realisierung eines globalen terrestrischen Referenzsystems wird als Referenzrahmen bezeichnet und ist durch Positionen zu einer Bezugsepoche und durch zeitlich lineare Bewegungen global verteilter Stationen festgelegt. Verschiedene Satellitenbeobachtungsverfahren können kombiniert werden, um ein globales terrestrisches Referenzsystem höchstmöglicher Genauigkeit, Stabilitä...

  10. Fragmentbefestigung bei zervikalen Wurzelfrakturen - Eine In-vitro-Untersuchung zur Verbundfestigkeit verschiedener Dentinadhäsivsysteme -

    OpenAIRE

    Heuchemer, Elmar

    2008-01-01

    Traumatische Verletzungen der Frontzähne treten bei Kindern und Jugendlichen zunehmend häufiger auf. Im jugendlichen Gebiss ist die prothetische Versorgung eines zervikal frakturierten Zahnes aufgrund des nicht abgeschlossenen Kiefer- und Wurzelwachstums nicht möglich. Kompositaufbau oder Fragmentwiederbefestigung sind Möglichkeiten den Zahn mit einer guten Ästhetik zu erhalten. Ziel dieser Arbeit war es herauszufinden, ob verschiedene Adhäsivsysteme signifikante Unterschiede in der Bruchfest...

  11. Fragmentbefestigung bei Wurzelfrakturen - Eine In-vitro-Untersuchung zum Bruchverhalten verschiedener Dentinadhäsivsysteme

    OpenAIRE

    Straßberger, Ulla

    2008-01-01

    In einer vorangegangenen In-vitro-Untersuchung wurden die pallatinalen Wurzeln menschlicher Molaren im Scherversuch (10mm/Min) gebrochen. Zahnfragmente wurden mit Hilfe verschiedener Dentinhaftvermittler (OptiBond FL, Syntac, Adhese, Prompt L-Pop und OptiBond FL in Kombination mit Tetrac Flow) adhäsiv wiederbefestigt. Die so rekonstruierte Zahneinheit wurde erneut an der ursprünglichen Bruchfläche gebrochen und die Bruchfestigkeit ermittelt. In der vorliegenden In-vitro-Untersuchung wurden di...

  12. Wissenstransfer unter dem Gesichtspunkt der Textoptimierung

    DEFF Research Database (Denmark)

    Kastberg, Peter

    2000-01-01

    Fachtexte `gleichen´ Themas aber verschiedener Textsortenzugehörigkeit führte zur Entwicklung eines Analyserasters, das eingesetzt werden kann, um den Prozeß des Transfers von Wissen zwischen Fachtexte verschiedener Fachtextsortenzugehörigkeit aus linguistischer Sicht näher zu beschreiben. Wenn ich ferner...

  13. "Künstliche Intelligenz" und Psychoanalyse: eine "Messalliance"?

    OpenAIRE

    Tietel, Erhard

    1996-01-01

    Der Beitrag analysiert einen Aufsatz von Sherry Turkle aus dem Winterheft 1988 des "DAEDALUS", dem Journal of the American Academy of Art and Sciences, mit dem Titel: "Artificial Intelligence and Psychoanalysis: a new alliance". Während S. Turkle in "Die Wunschmaschine" den Einfluss des Computers auf verschiedene Gruppen (Kinder, Jugendliche, Erwachsene) durchaus noch kritisch und abwägend darstellt und im wesentlichen Fragen aufwirft, zeigt sie bezüglich der Möglichkeiten der Künstlichen Int...

  14. ElevationDEM_DEM3p2M

    Data.gov (United States)

    Vermont Center for Geographic Information — This metadata applies to the following collection area(s): Chittenden County 2004 3.2m and Digital Elevation Model (DEM) datasets of various "hydro-treatments": DEM,...

  15. ElevationDEM_DEM1p6M2008

    Data.gov (United States)

    Vermont Center for Geographic Information — This metadata applies to the following collection area(s): Missisquoi Lower 2008 1.6m and Digital Elevation Model (DEM) datasets of various "hydro-treatments": DEM,...

  16. ElevationDEM_DEM0p7M2013

    Data.gov (United States)

    Vermont Center for Geographic Information — This metadata applies to the following collection area: Rutland/GI Counties 2013 0.7m and Digital Elevation Model (DEM) datasets of various "hydro-treatments": DEM,...

  17. ElevationDEM_DEM1p6M2010

    Data.gov (United States)

    Vermont Center for Geographic Information — This metadata applies to the following collection area(s): Missisquoi Upper 2010 1.6m and Digital Elevation Model (DEM) datasets of various "hydro-treatments": DEM,...

  18. ElevationDEM_DEM3p2M2004

    Data.gov (United States)

    Vermont Center for Geographic Information — This metadata applies to the following collection area(s): Chittenden County 2004 3.2m and Digital Elevation Model (DEM) datasets of various "hydro-treatments": DEM,...

  19. ElevationDEM_DEM0p7M2015

    Data.gov (United States)

    Vermont Center for Geographic Information — This metadata applies to the following collection area(s): Windham County 2015 0.7m and Digital Elevation Model (DEM) datasets of various "hydro-treatments": DEM,...

  20. ElevationDEM_DEM1p6M2012

    Data.gov (United States)

    Vermont Center for Geographic Information — This metadata applies to the following collection area(s): Addison County 2012 1.6m and Digital Elevation Model (DEM) datasets of various "hydro-treatments": DEM,...

  1. ASTER DEM performance

    Science.gov (United States)

    Fujisada, H.; Bailey, G.B.; Kelly, Glen G.; Hara, S.; Abrams, M.J.

    2005-01-01

    The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) instrument onboard the National Aeronautics and Space Administration's Terra spacecraft has an along-track stereoscopic capability using its a near-infrared spectral band to acquire the stereo data. ASTER has two telescopes, one for nadir-viewing and another for backward-viewing, with a base-to-height ratio of 0.6. The spatial resolution is 15 m in the horizontal plane. Parameters such as the line-of-sight vectors and the pointing axis were adjusted during the initial operation period to generate Level-1 data products with a high-quality stereo system performance. The evaluation of the digital elevation model (DEM) data was carried out both by Japanese and U.S. science teams separately using different DEM generation software and reference databases. The vertical accuracy of the DEM data generated from the Level-1A data is 20 m with 95% confidence without ground control point (GCP) correction for individual scenes. Geolocation accuracy that is important for the DEM datasets is better than 50 m. This appears to be limited by the spacecraft position accuracy. In addition, a slight increase in accuracy is observed by using GCPs to generate the stereo data. ?? 2005 IEEE.

  2. Vergleichende Untersuchung zum Einsatz verschiedener Erstbehandlungsmaßnahmen beim neonatalen Kalb unter Praxisbedingungen

    OpenAIRE

    Homberg, Julia

    2015-01-01

    Ziel dieser Untersuchung war es, den Einsatz von Fruchtwasserabsaugpumpen und das Aufhängen im Rahmen der Erstbehandlung von neugeborenen Kälbern zu vergleichen. Zu diesem Zweck wurde die Vitalität der Kälber post natum beurteilt. Außerdem wurde die Erkrankungshäufigkeit der Kälber in den ersten Lebenswochen ermittelt. Zusätzlich wurde untersucht, ob Störvariablen wie das Geschlecht des Kalbes, die Parität des Muttertieres, die geburtshilfliche Maßnahme und die Jahreszeit einen Einfluss au...

  3. Coastal Digital Elevation Models (DEMs)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Digital elevation models (DEMs) of U.S. and other coasts that typically integrate ocean bathymetry and land topography. The DEMs support NOAA's mission to understand...

  4. Der Einfluss des Ernährungsverhaltens auf die Rechte künftiger Generationen am Beispiel des Fleischkonsums in Deutschland

    Directory of Open Access Journals (Sweden)

    Schropp, Stephanie

    2013-06-01

    Full Text Available Künftige Generationen haben das Recht auf eine Welt, die mindestens den Lebensstandard und Komfort von heute ermöglicht. Schreitet die Erderwärmung allerdings in prognostiziertem Tempo voran, kann dies nicht mehr gewährleistet werden. Einen großen Einfluss auf CO2-Emissionen hat der Verbraucher mit seinem Ernährungsstil. Vor allem der Konsum von Fleisch weist eine schlechte Klimabilanz auf. Indirekte Folgen sind Armut in Entwicklungsländern (Nord-Süd-Konflikt und die Ausbeutung von Land und weiteren natürlichen Ressourcen künftiger Generationen. Ein bewusster und nachhaltiger Ernährungsstil kann dem entgegen wirken. Aber nicht nur der Konsument allein ist für die Reduzierung von Treibhausgas-Emissionen verantwortlich. Auch Politik und Handel sind gefordert. Denn nur in Gemeinschaft kann der Klimawandel verzögert und eine Generationengerechtigkeit aufrechterhalten werden.

  5. Untersuchungen zum Einfluss von sekundären Pflanzenstoffen auf die Thrombozytenaktivierung

    OpenAIRE

    Rosenkranz, J.T. (Jocheved)

    2012-01-01

    Von PMNL gebildete Sauerstoffradikale oxidieren körpereigene Proteine, die Thrombozyten aktivieren. In dieser Arbeit verwandtes Idea- HSA (= „Immune Defense Altered- Human Serum Albumin“) ist durch das MPO/ HOCl- System oxidiertes Albumin. Der Einfluss des Idea- HSA auf Thrombozyten und Monozyten und die Hemmbarkeit durch Antioxidantien wurde untersucht, ebenso wie der Einfluss von Parthenolid auf die Thrombozytenfunktion im LVAD INCOR Heart (Berlin Hearts AG). Idea- HSA ist ein starker Throm...

  6. Der Einfluss von personeller Einkommensverteilung auf die „Great Depression“ und die „Great Recession“

    Directory of Open Access Journals (Sweden)

    Stefan Trappl

    2015-12-01

    Full Text Available Der Einfluss gestiegener Einkommensungleichheit auf die „Great Depression“ und die „Great Recession“ wurde mehrfach postuliert (Galbraith 1954/2009; Eccles 1951; Rajan 2010; Stiglitz 2012; Piketty 2014. Konkrete empirische Arbeiten zum Zusammenhang zwischen Einkommensverteilung und dem Entstehen von Wirtschaftskrisen gibt es aber bislang wenige. Kumhof/Ranciere (2010 überprüften die von Rajan (2010 aufgestellte Hypothese, die einen entsprechenden Zusammenhang postuliert, mittels Modellrechnung. Bordo/Meissner (2012 und darauf aufbauend Gu/Huang (2014 verwendeten unterschiedliche Regressionsmodelle in Bezug auf einen entsprechenden Zusammenhang, ohne jedoch eindeutige Ergebnisse zu liefern. Die vorliegende Arbeit schließt an diese Arbeiten an, beschränkt die Untersuchung allerdings auf Staaten, für die Daten für die letzten hundert Jahre verfügbar sind, und untersucht zudem explizit die Zeiträume um die beiden größten Krisen der letzten hundert Jahre, die „Great Depression“ und die „Great Recession“. Die Auswertungen zeigen, dass die personelle Einkommensverteilung ein guter Prädiktor für die Kriseneintrittswahrscheinlichkeit ist.

  7. Der Einfluss von Alitretinoin auf die Lebensqualität bei Patienten mit schwerem chronischen Handekzem: FUGETTA - Beobachtungsstudie unter Praxisbedingungen.

    Science.gov (United States)

    Augustin, Matthias; Thaçi, Diamant; Kamps, Anja

    2016-12-01

    Alitretinoin ist die einzige zugelassene Behandlung für schweres chronisches Handekzem (CHE), das refraktär gegenüber potenten topischen Corticosteroiden ist. Bei dieser Studie (FUGETTA) wurde die Wirksamkeit von leitliniengerecht angewendetem oralem Alitretinoin sowie dessen Einfluss auf die Lebensqualität (LQ) bei Patienten mit schwerem refraktärem CHE beurteilt. Multizentrische, offene, nichtinterventionelle Beobachtungsstudie, durchgeführt in Deutschland. Die Patienten wurden nach Ermessen ihres behandelnden Arztes mit Alitretinoin 10 mg oder 30 mg einmal täglich über maximal 24 Wochen behandelt. Die Wirksamkeit wurde anhand des Physician Global Assessment (PGA) und des Dermatology Life Quality Index (DLQI) bewertet. Zudem wurden unerwünschte Ereignisse (UE) erfasst. Die Studienpopulation bestand aus 658 Patienten (30 mg: n = 581; 10 mg: n = 77). Bei Beobachtungsbeginn litten die meisten Patienten (83 %) gemäß PGA an einem schweren CHE. Bei Beobachtungsende war das Handekzem bei 48 % der Patienten gemäß PGA vollständig oder fast vollständig abgeheilt (30 mg: 49 %; 10 mg: 43 %). Die mittlere Verbesserung des DLQI-Scores in Woche 24 betrug 58 % (30 mg: mittlere [SD] Veränderung gegenüber dem Ausgangswert -10,4 [8,04]) und 70 % (10 mg: mittlere [SD] Veränderung gegenüber dem Ausgangswert -10,8 [7,29]). Die Gesamtinzidenz von NW war niedrig und in den beiden Gruppen ähnlich. Alitretinoin führte zu einer schnellen, deutlichen Verbesserung der LQ bei Patienten mit schwerem CHE. © 2016 Deutsche Dermatologische Gesellschaft (DDG). Published by John Wiley & Sons Ltd.

  8. The Oracle of DEM

    Science.gov (United States)

    Gayley, Kenneth

    2013-06-01

    The predictions of the famous Greek oracle of Delphi were just ambiguous enough to seem to convey information, yet the user was only seeing their own thoughts. Are there ways in which X-ray spectral analysis is like that oracle? It is shown using heuristic, generic response functions to mimic actual spectral inversion that the widely known ill conditioning, which makes formal inversion impossible in the presence of random noise, also makes a wide variety of different source distributions (DEMs) produce quite similar X-ray continua and resonance-line fluxes. Indeed, the sole robustly inferable attribute for a thermal, optically thin resonance-line spectrum with normal abundances in CIE is its average temperature. The shape of the DEM distribution, on the other hand, is not well constrained, and may actually depend more on the analysis method, no matter how sophisticated, than on the source plasma. The case is made that X-ray spectra can tell us average temperature, and metallicity, and absorbing column, but the main thing it cannot tell us is the main thing it is most often used to infer: the differential emission measure distribution.

  9. Vertrauen in Internetangebote. Eine empirische Untersuchung zum Einfluss von Glaubwürdigkeitsindikatoren bei der Nutzung von Online-Therapie- und Online-Beratungsangeboten (Dissertation

    Directory of Open Access Journals (Sweden)

    Waldemar Dzeyk

    2006-09-01

    Full Text Available Angesichts der Risiken, die mit der Nutzung von Online-Informationen verbunden sind, besitzen Fragen der Glaubwürdigkeit und des Vertrauens eine wichtige Orientierungsfunktion für die Selektion und Bewertung von Informationen im Internet. Für den Bereich gesundheitsrelevanter Online-Angebote ist bisher noch wenig darüber bekannt, welche Rolle medienseitige Merkmale für die Zuschreibung von Glaubwürdigkeit und die Entwicklung von Vertrauen in Online-Therapieangebote oder Online-Beratungsangebote spielen. Ebenso ist dass Wissen um den Einfluss rezipientenseitiger Merkmale sowie deren Interaktion mit den Medienmerkmalen bei der Zuschreibung von Glaubwürdigkeit im Kontext des Internets noch weitgehend unerforscht. Den Teilnehmer/innen eines Online-Experiments (N = 532 wurde das Angebot eines simulierten Online-Therapie bzw. Online-Beratungsangebots präsentiert. Dabei wurden verschiedene Glaubwürdigkeitsmerkmale der einzelnen Webseiten variiert: 1. Porträtfoto des Therapeuten, 2. Qualifikation des Therapeuten, 3. orthografische Korrektheit, 4. Ausführlichkeit der Informationen zur Datensicherheit und zum Datenschutz und 5. die Vollständigkeit der Kontaktadresse. Als abhängige Variable wurde die Einschätzung der Glaubwürdigkeit der dargebotenen Seiten erhoben (Vertrauenswürdigkeit und Kompetenz als Kernkomponenten des Glaubwürdigkeitskonstrukts. Zusätzlich wurden mittels eines Online-Fragebogens verschiedene Rezipientenvariablen erfasst. Für die Indikatoren "Qualifikation des Therapeuten", "Datensicherheit und Datenschutz" und für die "Kontaktadresse" konnten signifikante Haupteffekte für die Beurteilung der Glaubwürdigkeit gesichert werden. Hier war es jeweils so, dass den eher glaubwürdigen Varianten sowohl eine höhere Vertrauenswürdigkeit als auch eine höhere Kompetenz zugeschrieben wurde. Für die Rezipientenvariablen zeigten sich vor allem bei den Variablen "Interesse am Thema" und "Vertrauen in die Zuverl

  10. Coastal DEMs with Cross-Track Interferometry

    NARCIS (Netherlands)

    Greidanus, H.S.F.; Huising, E.J.; Platschorre, Y.; Bree, R.J.P. van; Halsema, D. van; Vaessen, E.M.J.

    1999-01-01

    Digital elevation models (DEMs) are produced from airborne radar cross-track interferometric measurements. Radar DEMs recorded from perpendicular orientations are intercompared, and compared to DEMs derived from airborne laser altimetry

  11. Mild cognitive impairment. Diagnostic value of different MR techniques; ''Mild cognitive impairment''. Diagnostische Wertigkeit verschiedener MR-Techniken

    Energy Technology Data Exchange (ETDEWEB)

    Hauser, T.; Stieltjes, B.; Essig, M. [Deutsches Krebsforschungszentrum (DKFZ) Heidelberg, Abteilung E010 Radiologie, Heidelberg (Germany); Thomann, P.A. [Zentrum fuer Psychosoziale Medizin, Universitaetsklinikum Heidelberg, AG Strukturelle Bildgebung, Klinik fuer Allgemeine Psychiatrie, Heidelberg (Germany)

    2011-04-15

    In view of an increasingly aging population the prevalence of dementia is also expected to increase rapidly. As well as clinical, neuropsychological and laboratory procedures magnetic resonance imaging (MRI) plays an important role in the early diagnosis of dementia which is important in the precursor stage of mild cognitive impairment (MCI). On the one hand this stage is associated with an increased risk of dementia and on the other hand an early treatment in this stage could attenuate development of the disease. In addition to morphological changes different functional MRI techniques can help in the early diagnosis of dementia and the precursor stages. Moreover, it is important to detect those MCI patients who are at particularly risk for developing dementia. In the differentiation of converters to non-converters initial studies suggest that particularly voxel-based morphometry, MR spectroscopy and diffusion tensor imaging can provide important additional information. (orig.) [German] Angesichts einer immer aelter werdenden Bevoelkerung sind wir mit dem Problem einer zunehmenden Zahl an Patienten mit Demenzerkrankungen konfrontiert. In der Fruehdiagnostik einer Demenz spielen neben klinischen, neuropsychologischen und laborchemischen Untersuchungen nichtinvasive Bildgebungsverfahren wie die MRT eine bedeutende Rolle. Wichtig ist dabei die Fruehdiagnostik einer Demenz bereits im Vorstadium der leichten kognitiven Beeintraechtigung (''mild cognitive impairment'', MCI), da dieses Krankheitsbild mit einem deutlich erhoehten Demenzrisiko einhergeht und durch eine fruehzeitige Therapie der Krankheitsverlauf abgemildert oder deutlich verzoegert werden kann. Neben morphologischen Veraenderungen helfen verschiedene funktionelle MR-Verfahren bei der Fruehdiagnostik einer Demenz. Darueber hinaus ist es von grosser Bedeutung, diejenigen MCI-Patienten zu detektieren, die in besonderem Masse von einer Demenz bedroht sind. Bei der Differenzierung von

  12. ElevationDEM_DEM0p7M2014

    Data.gov (United States)

    Vermont Center for Geographic Information — This metadata applies to the following collection area(s): Rutland/GI Counties 2013 0.7m and Digital Elevation Model (DEM) datasets of various "hydro-treatments":...

  13. ElevationDEM_DEM1p4m

    Data.gov (United States)

    Vermont Center for Geographic Information — "Bare Earth" Digital Elevation Model (DEM) data, i.e., a bare ground surface without any objects like plants and buildings on it, was derived from the best available...

  14. NOAA Tsunami Inundation DEM Project

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's National Geophysical Data Center (NGDC) is building high-resolution digital elevation models (DEMs) for select U.S. coastal regions. These integrated...

  15. Cost-benefit study of different application scenarios in teleradiology; Nutzwert- und Wirtschaftlichkeitsanalyse verschiedener Teleradiologieszenarien

    Energy Technology Data Exchange (ETDEWEB)

    Heckermann, D. [Inst. fuer Radiologische Diagnostik, Klinikum Grosshadern der Ludwig-Maximilians-Universitaet Muenchen (Germany); Wetekam, V. [Siemens AG, Medizinische Technik, Erlangen (Germany); Hundt, W. [Inst. fuer Radiologische Diagnostik, Klinikum Grosshadern der Ludwig-Maximilians-Universitaet Muenchen (Germany); Reiser, M. [Inst. fuer Radiologische Diagnostik, Klinikum Grosshadern der Ludwig-Maximilians-Universitaet Muenchen (Germany)

    1997-04-01

    With the increasing number of users and technical improvements, there are several application scenarios of teleradiology. To perform a cost-benefit analysis, an approach is presented, which focuses on both monetary and qualitative aspects. Process-related, qualitative and quantitative evaluations are described. The prestudy compares the radiological workflow before and after the introduction of a teleradiology system. A scoring model is part of the qualitative evaluation. The quantitative study focuses on costs and savings. Amortisation and a net present value of savings versus costs can be derived using dynamic investment methods. Savings can be achieved after a short time under ideal conditions, but there is no guarantee for a reimbursement for all systems. (orig.) [Deutsch] Im Zuge der Weiterentwicklung und steigenden Zahl an Nutzern von Teleradiologiesystemen ergibt sich eine Vielzahl von Anwendungsmoeglichkeiten. Um eine moeglichst allumfassende Kosten-Nutzen-Analyse dieser Systeme durchzufuehren, wird ein Modellansatz beschrieben, der neben monetaeren Aspekten qualitative Faktoren untersucht. Der Ansatz besteht aus einer Prozessanalyse, einer Nutzwertbetrachtung sowie einer Wirtschaftlichkeitsmessung. In der Prozessanalyse werden die Arbeitsweisen der konventionellen und teleradiologischen Umgebung gegenuebergestellt, um qualitative und monetaere Nutzenpotentiale zu erkennen. In der Nutzwertanalyse werden ueber ein Scoringmodell die qualitativen Faktoren individuell fuer beide Arbeitsweisen gewichtet und gemessen. Kosten und Einsparungspotentiale werden in der Wirtschaftlichkeitsanalyse anhand von Beispielen gegenuebergestellt. Anhand Methoden dynamischer Investitionsrechnung werden Amortisation und Kapitalwert verschiedener Teleradiologieszenarien ermittelt. Hierbei zeigt sich, dass unter speziellen Voraussetzungen relativ kurzfristig Einsparungen zu erzielen sind, jedoch keine allgemeingueltige Aussage ueber eine generelle Amortisation aller Systeme

  16. Linear and nonlinear approach for DEM smoothening

    Directory of Open Access Journals (Sweden)

    2006-01-01

    Full Text Available One of the biggest problems faced while analyzing digital elevation models (DEMs, particularly DEMs that are produced using photogrammetry, is to avoid pits and peaks in DEMs. Peaks and pits, which are errors, are generated during the surface generation process. DEM smoothening is an important preprocessing step meant for removing these errors. This paper discusses two linear DEM smoothening methods, Gaussian blurring and mean smoothening, and two nonlinear DEM smoothening methods, morphological smoothening and morphological smoothening by reconstruction. The four methods are implemented on a photogrammetrically generated DEM. The drainage network of the resultant DEM is obtained using skeletonization by morphological thinning, and the fractal dimension of the extracted network is computed using the box dimension method. The fractal dimensions are then compared to study the effects of the four smoothening methods. The advantages of nonlinear DEM smoothening over linear DEM smoothening are discussed. This study is useful in landscape descriptions.

  17. Einfluss von DNA-Variationen auf die koronare Herzerkrankung

    Directory of Open Access Journals (Sweden)

    Drexel H

    2008-01-01

    Full Text Available Erkenntnisse aus Familien- oder Zwillingsstudien lassen auf einen hohen genetischen Hintergrund der koronaren Herzerkrankung (KHK schließen. Seit einiger Zeit versucht man mittels intensiver Forschung, die genetischen Faktoren, welche das kardiovaskuläre Risiko beeinflussen, zu identifizieren. Aufgrund der hohen Frequenz der KHK in der Bevölkerung spielen hierbei Mendel’sche Erkrankungen, wie die familiäre Hypercholesterinämie, nur eine untergeordnete Rolle. Anhand der Ergebnisse aus Kopplungs- und Assoziationsstudien sind bisher zahlreiche DNA-Polymorphismen in Kandidatengenen als potenzielle genetische Risikofaktoren für die KHK vorgeschlagen worden. Die möglichen Auswirkungen dieser Polymorphismen auf das Erkrankungsrisiko werden in der Literatur allerdings meist kontrovers diskutiert. Metaanalysen haben gezeigt, dass DNA-Polymorphismen der Gene für Apolipoprotein E, Cholesteryl Ester Transfer-Protein, Faktor V, Prothrombin und Adiponektin einen signifikanten Zusammenhang mit der KHK aufweisen. Die jüngste Entwicklung von technischen Verfahren für die Hochdurchsatzgenotypisierung sowie die wachsende Kenntnis um die Strukturierung des Genoms in Haplotypen eröffnete der Forschung neue Möglichkeiten für die Ermittlung des genetischen Einflusses auf die KHK. Infolgedessen konnten mehrere unabhängig durchgeführte genomweite Assoziationsstudien den chromosomalen Abschnitt 9p21 erstmalig als genetischen Modulator für die KHK identifizieren. Die genaue Wirkweise dieser in der Region 9p21 lokalisierten DNA-Variationen auf die Entstehung der KHK ist bis dato allerdings unbekannt. Zukünftige technologische Entwicklungen, wie das "next generation sequencing", werden innerhalb absehbarer Zeit die Forschung über den Zusammenhang zwischen genetischer Variabilität und der KHK weiter maßgeblich beeinflussen. Durch dieses Wissen wird es uns gelingen, das KHK-Risiko besser abschätzen zu können und neue Therapien auf Personen mit hohem

  18. Das Problem der sogenannten zusammengesetzten Bezirke auf dem Balkan im 11. Jahrhundert: Zwei fallbeispiele

    Directory of Open Access Journals (Sweden)

    Krsmanović Bojana

    2009-01-01

    Full Text Available (nemački In der vorliegenden Arbeit wurden Charakteristika der sogenannten zusammengesetzten militärisch-zivilen Bezirke behandelt, die aus zwei oder drei Untereinheiten bestanden. Diese Untereinheiten der zusammengesetzten Bezirke hatten in der Regel feste zivile und militärische Verwaltungsstrukturen, d.h. sie hatten eine gewisse Unabhängigkeit. Ein zusammengesetzter Bezirk konnte in den Quellen als ein 'thema' (im Singular bezeichnet werden oder auch im Plural als 'themata'. An seiner Spitze befand sich ein Dux/katepano oder gelegentlich auch ein Stratege. Der zivilen Verwaltung stand ein Richter/Prätor vor, welcher häufig das Amt eines anagrapheus innehatte. Weiterhin wurde der zusammengesetzte Bezirk Voleron-Strymon-Thessalonike naher untersucht sowie die Probleme, die mit dem Status seiner Unterheiten, insbesondere mit Voleron, zusammenhängen. Es ist möglich, dass aus denjenigen Gebieten des Balkans, die nach dem Jahr 1018 unter byzantinische Herrschaft gefallen waren, ein zusammengesetzter Bezirk gebildet wurde. Die Rede ist von dem Thema Bulgaria-Sirmium-Paradounavon. Es wird vermutet, dass die demographischen Umstände sowie die ethnische Zusammensetzung der Bevölkerung der Region Einfluss auf die Charakteristika des zusammengesetzten Bezirks hatten. Die zivile Verwaltungsstruktur war hier nicht derart beständig wie in den anderen Gebieten des Balkans, die bereits vor dem Krieg von 976-1018 unter byzantinischer Herrschaft standen. Sirmium und Paradounavon scheinen im zivilen Bereich der Verwaltung von Amtsträgern aus Bulgarien geleitet worden zu sein, wahrend die militärische Führung anscheinend unabhängig von Bulgarien war.

  19. Demência de alzheimer

    OpenAIRE

    Galvão, Ana Maria

    2011-01-01

    A doença de Alzheimer é considerada a demência mais comum no ser humano, sendo caraterizada como um distúrbio degenerativo do cérebro que leva à perda de memória (Alzheimer's Association, 2010). A notícia de um diagnóstico de demência causa um intenso impacto na vida de pacientes e familiares. Os principais motivos referem-se à impossibilidade de cura e à progressão por vezes rápida dos sintomas. São comumente evidenciadas reações emocionais negativas envolvendo impotência, medo e...

  20. Pollutants from road traffic and breathing problems in children; Schadstoffe aus dem Strassenverkehr und Atemwegsbeschwerden bei Kindern

    Energy Technology Data Exchange (ETDEWEB)

    Mutius, E. von [Muenchen Univ. (Germany). Dr. von Haunersche Kinderklinik

    1996-06-01

    So far, there ave been few studies on measurable health effects of emissions from road traffic. An analysis of the available studies yields no clear indication of a relationship between road traffic emissions and the incidence of asthma and allergies in infants. On the other hand, there are no valid data on individual pollutant exposure of infants in the framework of epidemiological studies which take account of other influencing factors.(orig./MG) [Deutsch] Der Frag, ob eine Schadstoffbelastung durch den Strassenverkehr einen messbaren schaedigenden Effekt auf die menschliche Gesundheit hat, ist bislang in wenigen Studien nachgegangen worden. Analysiert man die vorliegenden Studien, ergibt sich derzeit kein eindeutiger Hinweis auf einen starken Zusammenhang zwischen der Strassenverkehrsbelastung und dem Auftreten von Asthma und Allergien beim Kind. Allerdings fehlt es an validen Daten zur individuellen Schadstoffexposition bei Kindern im Rahmen epidemiologischer Studien, ie eine Beruecksichtigung anderer Einfluss- und Stoervariablen erlauben. (orig/MG)

  1. Photocatalytic hydrogen production on SOLECTRO {sup registered} titanium dioxide layers. Investigation of reaction processes and of the influence of various reaction parameters; Photokatalytische Wasserstoffgewinnung an SOLECTRO {sup registered} -Titandioxidschichten. Untersuchung der ablaufenden Reaktionsprozesse und des Einflusses verschiedener Reaktionsparameter

    Energy Technology Data Exchange (ETDEWEB)

    Keil, Doreen

    2010-04-14

    The dissertation investigated the reaction processes of photocatalytic hydrogen production on palladium and copper-doped SOLECTRO {sup registered} titanium dioxide layers. Methanol was used as electron donor. [German] In dieser Doktorarbeit werden die ablaufenden Reaktionsprozesse der photokatalytischen Wasserstoffentwicklung an palladium- und kupferbeladenen SOLECTRO {sup registered} -Titandioxidschichten untersucht. Als Elektronendonator wurde Methanol verwendet.

  2. Digtial Elevation Model (DEM) 250K

    Data.gov (United States)

    Kansas Data Access and Support Center — Digital Elevation Model (DEM) is the terminology adopted by the USGS to describe terrain elevation data sets in a digital raster form. The standard DEM consists of a...

  3. Digitial Elevation Model (DEM) 100K

    Data.gov (United States)

    Kansas Data Access and Support Center — Digital Elevation Model (DEM) is the terminology adopted by the USG to describe terrain elevation data sets in a digital raster form. The standard DEM consists of a...

  4. ElevationDEM_DEMHF2M2012

    Data.gov (United States)

    Vermont Center for Geographic Information — This metadata applies to the following collection area(s): Bennington County 2012 2.0m and Digital Elevation Model (DEM) datasets of various "hydro-treatments": DEM,...

  5. Digital Elevation Model (DEM) 24K

    Data.gov (United States)

    Kansas Data Access and Support Center — Digital Elevation Model (DEM) is the terminology adopted by the USGS to describe terrain elevation data sets in a digital raster form. The standard DEM consists of a...

  6. Total balance of biogenic fuels for thermal uses; Ganzheitliche Bilanzierung verschiedener biogener Festbrennstoffe zur thermischen Nutzung

    Energy Technology Data Exchange (ETDEWEB)

    Becher, S.; Kaltschmitt, M. [Stuttgart Univ. (Germany). Inst. fuer Energiewirtschaft und Rationelle Energieanwendung (IER)

    1996-12-31

    In this situation of unfavourable energy price levels, the use of biogenic fuels for power supply can be recommended only if it serves to reduce environmental pollution. Against this background and on the basis of a primary energy balance, the authors attempted a total balance of selected enfironmental effects (global heating and acidification potential) of biomass use as compared to fossil fuel combustion. (orig) [Deutsch] ie Nutzung biogener Festbrennstoffe zur Energienachfragedeckung ist bei dem gegenwaertigen unguenstigen Energiepreisniveau nur dann zu rechtfertigen, wenn es durch die Biomassenutzung zu einer Reduzierung der energiebedingten Umwelteffekte kommt. Vor disem Hintergrund werden ausgehend von der Primaerenergiebilanz ausgewaehlte Umwelteffekte (d.h. das Treibhaus- und das Versauerungspotential) einer Biomassenutzung im Vergleich zu einer Nutzung fossiler Energietraeger ganzheitlich bilanziert. Die wesentlichen Ergebnisse werden zusammengefasst und interpretiert. (orig)

  7. Systematic analysis of geothermal plants. Influence of temperatures in consumer systems on the specific cost of the distributed heat; Systemanalytische Erfassung von Nutzungsanlagen hydrogeothermaler Ressourcen. Einfluss der Temperaturen in den Abnehmersystemen auf den Waermegestehungspreis

    Energy Technology Data Exchange (ETDEWEB)

    Schallenberg, K. [GeoForschungsZentrum Potsdam (Germany)

    1997-12-01

    On the basis of a general investigation of the impact of geological situation, thermal water loop and consumer structure on the economy of heating systems, different geothermal plants are analysed in detail. In the study, for example, variations of the temperature conditions in district heating systems were considered while the geologic conditions are maintained. It is shown that the specific costs calculated for the distributed heat are sensitive to the amount of heat extracted from the Earth`s interior. Therefore, it was necessary to make assumptions for the duration curve of the consumer system. An exponential duration curve was verified by comparison with data from an existing district heating system. The calculated specific heat costs for different network layouts are transformed finally into an equivalent investment potential. The results clearly indicate the possibilities for an optimization of the system when investments into the heating network would be made. (orig.) [Deutsch] Hydrogeothermale Nutzungsanlagen wurden auf Basis der Einflussgroessen Geologie, Thermalwasserkreis und Abnehmerstruktur systemanalytisch erfasst. Daraus ergibt sich die Grundlage zum Vergleich verschiedener Anlagen. Nachhaltige Einfluesse auf die Wirtschaftlichkeit von Geothermieanlagen ergeben sich aus der Betriebsweise der Abnehmerstruktur. Die dargestellten Untersuchungen zielen deshalb zunaechst auf die Variation der Temperaturparameter des Netzes und deren Einfluss auf die Waermegestehungskosten ab. Bei diesem Ansatz wurden zunaechst die geologischen Eingangsgroessen konstant gehalten. Grundlage der statischen Kostenrechnung in Anlehnung an VDI 2067 ist eine Kostenzusammenstellung der Einzelkomponenten einer geothermischen Heizzentrale. Um den geothermischen Beitrag zur Waermeversorgung moeglichst genau zu beschreiben, ist die Kenntnis von geordneten Jahresganglinien der Abnehmersysteme erforderlich. Zur mathematischen Beschreibung diente eine Exponentialfunktion, deren

  8. Influence of autochthonous micro-organisms on sorption and remobilization of technetium and selenium. Final report; Einfluss der autochthonen Mikroflora auf die Sorption und Remobilisierung des Technetiums und des Selens. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Maue, G.; Stroetmann, I.; Dott, W. [Technische Univ. Berlin (Germany). Fachgebiet Umwelthygiene; Taute, T.; Winkler, A.; Pekdeger, A. [Freie Univ. Berlin (Germany). Fachrichtung Rohstoff- und Umweltgeologie

    1996-10-31

    Within this research project the influence of autochthonous mirco-organisms on immobilization and remobilization of Technetium and Selenium was investigated. Both redoxsensitive radionuclides are part of the waste of nuclear fuel (Tc app. 6%). Former investigations have shown, that immobilization behaviour of both elements could be influenced by micro-organisms. It has not been known, if the autochthonous (or in situ) organisms from greater depth do also have an influence on radionuclide mobility. The autochthonous populations of micro-organisms in deep sediments and their influence on the migration of Tc and Se were investigated in this study. For this reason recirculation column experiments were carried out. Absolutely sterile and anaerobic handling was necessary for the sampling and the further treatment of the sediments and waters used in the experiments. Therefor special methods for sampling, storage and handling had been developed. The results of recirculation column test with autochthonous micro-organisms were compared with sterile parallel tests and were verified with the results of an elaborated version of the hydrogeochemical equilibration code PHREEQE. It was shown that the autochthonous micro-organisms had only very little influence on the migration behaviour. The reason is the very low population (less than 10 E+6 CFU). Nevertheless it has to be taken into consideration, that conventional laboratory experiments for the estimation of the retention capacities of sediments for hazardous waste lead to an overestimation, if the sediments are contaminated with allochthonous micro-organisms (CFU=colony forming units). (orig.) [Deutsch] In dem Forschungsvorhaben wurde der Einfluss der autochthonen Mikroorgansimen auf die Mobilitaet von Technetium und Selen untersucht. Beide redoxsensitiven Radionuklide sind im Abfall von Kernbrennelementen enthalten (Tc ca. 6%). Aus vorangegangenen Forschungsarbeiten ist bekannt, dass die Mobilitaet der beiden Elemente durch

  9. Radioiodine therapy of Graves' disease - a dosimetric comparison of different strategies concerning antithyroid drugs; Radioiodtherapie des Morbus Basedow - dosimetrischer Vergleich verschiedener Therapieregime bezueglich der Thyreostatikabgabe

    Energy Technology Data Exchange (ETDEWEB)

    Urbannek, V.; Voth, E.; Moka, D.; Schicha, H. [Klinik und Poliklinik fuer Nuklearmedizin, Medizinische Einrichtungen der Univ. zu Koeln (Germany)

    2001-08-01

    -half-life, but it is inferior to stopping ATD 2 days prior to RITh. (orig.) [German] Ziel: Eine thyreostatische Medikation (TM) waehrend einer Radioiodtherapie (RITh) fuehrt im Vergleich zu nicht thyreostatisch behandelten Patienten zu einer prozentualen Zunahme an Therapieversagern oder erfordert einen erhoehten Verbrauch an Radioiod (RI). Andererseits ist aus klinischen Gruenden und wegen des in der Hyperthyreose beschleunigten lodstoffwechsels vor RITh eine Kompensation der Stoffwechsellage anzustreben. Ziel dieser Studie war daher, am Beispiel des Morbus Basedow den Einfluss der TM auf die Biokinetik von RI zu untersuchen, um die RITh bei thyreostatisch vorbehandelten Patienten zu optimieren. Methoden: Eingeschlossen wurden 385 konsekutive Patienten, die wegen eines Morbus Basedow erstmalig eine RITh erhielten: Kollektiv A (n = 74): Durchfuehrung der RITh unter laufender TM; Kollektiv B (n = 111): Beginn der RITh unter TM, Absetzen von TM 1-5 Tage nach RITh, falls RI-Uptake unzureichend oder RI-HWZ verkuerzt (n = 61); Kollektiv C (n = 200): Absetzen von TM 2 Tage vor RITh bei allen Patienten. Betrachtet wurde der Einfluss von thyreostatischer Medikation auf den RI-Uptake, die RI-HWZ sowie die an der Schilddruese erzielte Energiedosis in Abhaengigkeit vom SD-Volumen und der eingesetzen RI-Aktivitaet [Therapieeffizienzquotient TEQ, (2)]. Ergebnisse: Im RI-Test (alle Patienten unter TM) war der RI-Uptake in den drei Kollektiven vergleichbar. Bei der RITh waren RI-Uptake, RI-HWZ{sub eff} und damit auch TEQ im Kollektiv C signifikant groesser als in den Kollektiven A und B (jeweils p<0,001). Im Kollektiv B wurde die TM bei 61 der 111 Patienten 1-5 Tage nach RITh abgesetzt. In diesem Unterkollektiv stieg die RI-HWZ von 4,4 {+-} 1,7 d auf 5,1 {+-} 1,6 d nach Absetzen der TM an (p = 0,001). Schlussfolgerung: Absetzen von TM 2 Tage vor RITh fuehrt im Vergleich zur Durchfuehrung der RITh unter TM zu einer Steigerung der Effizienz (TEQ) von etwa 50% und damit zu einer deutlichen

  10. Coverage Polygons for DEMs of the North-Central California Coast (DEM_coverage_areas.shp)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A GIS polygon shapefile outlining the extent of the 14 individual DEM sections that crompise the seamless, 2-meter resolution DEM for the open-coast region of the...

  11. Coverage Polygons for DEMs of the North-Central California Coast (DEM_coverage_areas.shp)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A GIS polygon shapefile outlining the extent of the 14 individual DEM sections that crompise the seamless, 2-meter resolution DEM for the open-coast region of the...

  12. Einfluss von abiotischen Faktoren auf Wuchs und Scopolamin-Biosynthese in Duboisia myoporoides.

    Directory of Open Access Journals (Sweden)

    Ullrich, Sophie Friederike

    2014-09-01

    Full Text Available Duboisia ist eine in Australien beheimatete Pflanze aus der Familie der Nachtschattengewächse, die Tropanalkaloide als sekundäre Pflanzeninhaltsstoffe enthält, deren quantitativ und ökonomisch bedeutsamstes Scopolamin ist. Um neue Erkenntnisse hinsichtlich des Einflusses abiotischer Faktoren auf Wuchs und Scopolamin-Biosynthese zu gewinnen, wurden Pflanzen der Art Duboisia myoporoides in Hydrokultur in Klimakammern unter streng kontrollierten Bedingungen angebaut (kalibrierte Einstellungen für Beleuchtungsdauer, Lichtintensität und Temperatur. Wichtige Messgrößen stellten dabei Biomasse und Alkaloidgehalt dar, letzterer gemessen mittels UHPLC und LC-MS.

  13. Sewage sludge disintegration - a review of current processes; Klaerschlammdesintegration - Ueberblick ueber verschiedene Verfahren

    Energy Technology Data Exchange (ETDEWEB)

    Nickel, K. [ULTRAWAVES Wasser- und Umwelttechnologien GmbH, Hamburg (Germany); Neis, U. [Technische Univ. Hamburg-Harburg, Hamburg (Germany). Arbeitsbereich Abwasserwirtschaft

    2003-07-01

    Anaerobic stabilisation is an established technology for reducing sewage sludge volumes, but it has the drawback of low conversion rates. The speed of the process is determined by the hydrolysis of the solid fraction of the sludge. According to the current state of knowledge, exoenzymes produced by the fermenting microorganisms attack the particulate material and dissolve monomers. Production of exoenzymes is an energy-consuming process for the microorganisms; it reduces the energy gain and slows down cell growth. The same bacteria are responsible for aerobic and anaerobic hydrolysis. Therefore, the process of sludge destabilisation can be intensified considerably by making the whole organic fraction biologically available, i.e. by replacing the slow stage of enzymatic sludge hydrolysis by a chemical, thermal or mechanical stage. Sludge disintegration by one of these processes would intensify anaerobic degradation, reduce sludge volumes and enhance biogas production. (orig.) [German] Die anaerobe Stabilisierung ist anerkannte Regel der Technik und fuehrt zu einem teilweisen Abbau der organischen Bestandteile des Rohschlammes. Eine Verminderung der zu entsorgenden Schlammmasse geht damit einher. Wesentlicher Nachteil der anaeroben Klaerschlammstabilisierung ist die geringe Umsatzleistung dieses Prozesses. Dem Aufschluss der Feststoffe/grossen Molekuele des Schlammes kommt eine Schluesselrolle zu: die Hydrolyse der Rohschlammfeststoffe stellt den geschwindigkeitsbestimmenden Teilschritt des aneroben Abbauprozesses dar. Nach den gegenwaertigen Vorstellungen greifen von den fermentierenden Mikroorganismen produzierte Exoenzyme das partikulaere Material an und loesen Monomere heraus. Die Herstellung der Exoenzyme ist fuer die Mikroorganismen energetisch sehr aufwendig und vermindert den Energiegewinn und damit das Zellwachstum. Die Hydrolyse ist unabhaengig davon, ob sie aerob oder anaerob erfolgt, sie wird von denselben Bakterien bewerkstelligt. Man kann sich demnach

  14. Convolutional Neural Network Based dem Super Resolution

    Science.gov (United States)

    Chen, Zixuan; Wang, Xuewen; Xu, Zekai; Hou, Wenguang

    2016-06-01

    DEM super resolution is proposed in our previous publication to improve the resolution for a DEM on basis of some learning examples. Meanwhile, the nonlocal algorithm is introduced to deal with it and lots of experiments show that the strategy is feasible. In our publication, the learning examples are defined as the partial original DEM and their related high measurements due to this way can avoid the incompatibility between the data to be processed and the learning examples. To further extent the applications of this new strategy, the learning examples should be diverse and easy to obtain. Yet, it may cause the problem of incompatibility and unrobustness. To overcome it, we intend to investigate a convolutional neural network based method. The input of the convolutional neural network is a low resolution DEM and the output is expected to be its high resolution one. A three layers model will be adopted. The first layer is used to detect some features from the input, the second integrates the detected features to some compressed ones and the final step transforms the compressed features as a new DEM. According to this designed structure, some learning DEMs will be taken to train it. Specifically, the designed network will be optimized by minimizing the error of the output and its expected high resolution DEM. In practical applications, a testing DEM will be input to the convolutional neural network and a super resolution will be obtained. Many experiments show that the CNN based method can obtain better reconstructions than many classic interpolation methods.

  15. Automated Quality Control for Ortholmages and DEMs

    DEFF Research Database (Denmark)

    Höhle, Joachim; Potucková, Marketa

    2005-01-01

    The checking of geometric accurancy of orthoimages and digital elevation models (DEMs) is discussed. As a reference, an existing orthoimage and a second orthoimage derived from an overlapping aerial image, are used. The proposed automated procedures for checking the orthoimages and DEMs are based...

  16. A Case Study of Using External DEM in InSAR DEM Generation

    Institute of Scientific and Technical Information of China (English)

    ZHOU Chunxia; GE Linlin; E Dongchen; CHANG Hsingchung

    2005-01-01

    Synthetic aperture radar interferometry (InSAR) has been used as an innovative technique for digital elevation model (DEM) and topographic map generation. In this paper, external DEMs are used for InSAR DEM generation to reduce the errors in data processing. The DEMs generated from repeat-pass InSAR are compared. For steep slopes and severe changes in topography, phase unwrapping quality can be improved by subtracting the phase calculated from an external DEM. It is affirmative that the absolute height accuracy of the InSAR DEM is improved by using external DEM. The data processing was undertaken without the use of ground control points and other manual operation.

  17. Der Einfluss von Tests auf Studienleistung und Leistung [The Effects of Tests on Study Behavior and Performance

    NARCIS (Netherlands)

    Dirkx, Kim; Kester, Liesbeth; Kirschner, Paul A.

    2012-01-01

    Dirkx, K. J. H., Kester, L., & Kirschner, P. A. (2012, 24 September). Der Einfluss von Tests auf Studienverhalten und Leistung [The Effects of Study Behavior and Performance]. Presentation at the Leibniz Institute for Pedagogies in Sciences and Mathematics (IPN), Kiel, Germany.

  18. Investigation for a chemical and physical description of different types of biomass; Untersuchung zur chemischen und physikalischen Beschreibung verschiedener Biomassen

    Energy Technology Data Exchange (ETDEWEB)

    Stuelpnagel, R. [Kassel Univ. (Gesamthochschule), Witzenhausen (Germany). Inst. fuer Nutzpflanzenkunde

    1998-09-01

    If the same type of biomass is harvested at different times, preserved by different technques and then processed into fuel, the physical and chemical characteristics of the fuel will differ. After describing biomass fuel of the `wet line`, the author carried out investigations of lumpiness, bulk density and materials density of chopped materials in order to obtain a preliminary physical characterisation. Two samples of wood chips were characterized as well. The chemical description started with an analysis of nutrient content, acidity and concentrations of fermentation acids in the `wet line` biomass. (orig.) [Deutsch] Wird die gleiche Biomasse zu unterschiedlichen Zeitpunkten geerntet, auf verschiedenen Wegen konserviert und beim Feuchtgut mechanisch zu Brennstoff aufbereitet, so wird dies Einfluss auf die physikalischen und chemischen Charakteristika eines Brennstoffes nehmen. Nach einer ersten Beschreibung des Brennstoffes Biomasse aus der `Feuchtgutlinie` sollten durch Untersuchungen zur Stueckigkeit, Schuettdichte und Materialdichte von Haeckselgut aus beiden Verfahren eine erste physikalische Charakterisierung durchgefuehrt werden, in die auch zwei Proben von Holzhackschnitzeln einbezogen wurde. Mit der Analyse der Naehrstoffgehalte sowie der Aciditaet und der Gehalte an Gaersaeuren in den Biomassen aus der Feuchtgutlinie sollte die chemische Beschreibung begonnen werden. (orig.)

  19. Moderne Behandlungsoptionen des sekundären Hyperparathyreoidismus vor dem Hintergrund kardiovaskulärer Kalzifizierung

    Directory of Open Access Journals (Sweden)

    Zitt E

    2014-01-01

    Full Text Available Der sekundäre Hyperparathyreoidismus (sHPT hat unbehandelt deletäre Auswirkungen auf verschiedene Organsysteme. In den vergangenen Jahren ist die kardiovaskuläre Kalzifizierung als Folge der mit dem sHPT einhergehenden Veränderungen des Knochen- und Mineralstoffwechsels und der zu dessen Therapie eingesetzten medikamentösen Interventionen in den Mittelpunkt der Forschung und Behandlungskonzepte gerückt. Sämtliche eingesetzten Therapien sind effektiv im Hinblick auf eine Korrektur der laborchemisch fassbaren Veränderungen im Rahmen des sHPT, aber nur sehr wenige auch klinisch in ihrer Auswirkung auf die kardiovaskuläre Kalzifizierung und patientenbezogene Endpunktdaten (Mortalität, kardiovaskuläre Morbidität in aussagekräftigen Studien untersucht. Das Fehlen qualitativ hochwertiger randomisierter kontrollierter Studien darf nicht zu einem nihilistischen Ansatz führen. Aufgrund unzureichender Daten ist keine der Therapieoptionen (Phosphatbinder, Vitamin-D-Substitution, Kalzimimetikum, Parathyreoidektomie grundsätzlich den anderen überlegen. Ein breiteres therapeutisches Fenster verlangt oft eine Kombination dieser Behandlungsoptionen und eine Individualisierung der sHPT-Therapie.

  20. VT Lidar DEM (1 meter) - 2005 - Essex

    Data.gov (United States)

    Vermont Center for Geographic Information — (Link to Metadata) This metadata applies to the following collection area(s): Essex County 2005 1m and Digital Elevation Model (DEM) datasets of various...

  1. Elektromagnetische Strahlung. Informationen aus dem Weltall.

    Science.gov (United States)

    Schäfer, H.

    Contents: Informationen aus dem Weltall. Neue und zukünftige Geräte. Wichtiges und Interessantes aus der Positionsastronomie. Die Helligkeit der Sterne und anderer astronomischer Objekte. Spektroskopie und Spektralanalyse. Beobachtungen außerhalb des optischen Bereiches.

  2. VT Lidar DEM (1 meter) - 2009 - Washington

    Data.gov (United States)

    Vermont Center for Geographic Information — (Link to Metadata) This metadata applies to the following collection area(s): Essex County 2005 1m and Digital Elevation Model (DEM) datasets of various...

  3. Adaptive Filter in SAR Interferometry Derived DEM

    Institute of Scientific and Technical Information of China (English)

    XU Caijun; WANG Hua; WANG Jianglin; GE Linlin

    2005-01-01

    In this paper, the performance of median filter, elevation dependent adaptive sigma median filter, and directionally dependent adaptive sigma median filter are tested on both InSAR Tandem DEM and simulated high-level noisy DEM. Through the comparison, the directionally dependent adaptive sigma median filter is proved to be the most effective one not only in the noise removing but also in the boundary preserve.

  4. DEM FROM SAR:PRINCIPLE AND APPLICATION

    Institute of Scientific and Technical Information of China (English)

    LiDeren; YangJie

    2003-01-01

    The paper gives an overview of the principle and application of generating DEM from SAR, including the principle and processing flow of generating DEM from single SAR and SAR interferometry. Afterwards, the application fields of InSAR for terrain surveying, volcanic terrain surveying and D—InSAR for monitoring ground subsiding are listed and described as well. The problem and prospect of application are also pointed out in the last part of this paper.

  5. DEM FROM SAR:PRINCIPLE AND APPLICATION

    Institute of Scientific and Technical Information of China (English)

    Li Deren; Yang Jie

    2003-01-01

    The paper gives an overview of the principle and application of generating DEM from SAR, including the principle and processing flow of generating DEM from single SAR and SAR interferometry. Afterwards, the application fields of InSAR for terrain surveying, volcanic terrain surveying and D-InSAR for monitoring ground subsiding are listed and described as well.The problem and prospect of application are also pointed out in the last part of this paper.

  6. Inverter integrated in module - a comparison of different circuit concepts regarding costs, volumes and efficiency; Modulintegrierte Wechselrichter - ein Vergleich verschiedener Schaltungskonzepte bezueglich Kosten, Volumen und Wirkungsgrad

    Energy Technology Data Exchange (ETDEWEB)

    Myrzik, J. [Kassel Univ. (Gesamthochschule) (Germany); Krieger, T.; Zacharias, P. [Institut fuer Solare Energieversorgungstechnik (ISET), Kassel (Germany); Nijs, J.; Mey, B. de [IMEC, Leuven (Belgium); O`Mathuna, S.; Meinhardt, M. [NMRC, Cork (Ireland); Held, E. de; Jantsch, M. [ECN, Petten (Netherlands); Hofkens, H. [SOLTECH, Leuven (Belgium)

    1998-12-01

    In the context of a project supported by the EU, a miniaturised PV inverter integrated in a module is being developed as a laboratory sample. The main aim of this project is the provision of know-how for the industry. In order to provide aids to decision-making for industrial manufacture, different lines of development are being worked out for this purpose. The systematic listing and judging of different inverter topologies has proved successful in the development of a string inverter. To determine a suitable inverter topology, a systematic procedure is shown in this article, which was carried out with the aid of different circuit calculations. [Deutsch] Im Rahmen eines von der EU gefoerderten Projektes wird ein modulintegrierter, miniaturisierter PV-Wechselrichter als Labormuster entwickelt. Uebergeordnetes Ziel dieses Projektes ist die Bereitstellung von Know-how fuer die Industrie. Hierzu werden verschiedene Entwicklungslinien erarbeitet, um Entscheidungshilfen fuer die industrielle Fertigung bereit zu stellen. Bereits bei der Entwicklung eines Stringwechselrichters hat sich die systematische Aufstellung und Beurteilung verschiedener Wechselrichtertopologien bewaehrt. Zur Ermittlung einer geeigneten Wechselrichtertopologie wird in diesem Beitrag eine systematische Vorgehensweise aufgezeigt, die mit der Hilfe verschiedener Schaltungskalkulationen durchgefuehrt wurde. (orig.)

  7. An assessment of TanDEM-X GlobalDEM over rural and urban areas

    Science.gov (United States)

    Koudogbo, Fifamè N.; Duro, Javier; Huber, Martin; Rudari, Roberto; Eddy, Andrew; Lucas, Richard

    2014-10-01

    Digital Elevation Model (DEM) is a key input for the development of risk management systems. Main limitation of the current available DEM is the low level of resolution. DEMs such as STRM 90m or ASTER are globally available free of charge, but offer limited use, for example, to flood modelers in most geographic areas. TanDEM-X (TerraSAR-X add-on for Digital Elevation Measurement), the first bistatic SAR can fulfil this gap. The mission objective is the generation of a consistent global digital elevation model with an unprecedented accuracy according to the HRTI-3 (High Resolution Terrain Information) specifications. The mission opens a new era in risk assessment. In the framework of ALTAMIRA INFORMATION research activities, the DIAPASON (Differential Interferometric Automated Process Applied to Survey Of Nature) processing chain has been successfully adapted to TanDEM-X CoSSC (Coregistered Slant Range Single Look Complex) data processing. In this study the capability of CoSSC data for DEM generation is investigated. Within the on-going FP7 RASOR project (Rapid Analysis and Spatialisation and Of Risk), the generated DEM are compared with Intermediate DEM derived from the TanDEM-X first global coverage. The results are presented and discussed.

  8. Bioverfügbarkeit verschiedener Darreichungsformen von clathriertem Dehydroepiandrosteron (DHEA) gegenüber nativem DHEA bei Frauen mit Nebennierenrindeninsuffizienz

    OpenAIRE

    Günther, Susann Margot Louise

    2006-01-01

    Bei Patientinnen mit chronischer Nebennierenrindeninsuffizienz liegt - neben dem Mangel an Glukokortikoiden und Mineralokortikoiden - ein Defizit an adrenalen Androgenen, nämlich Dehydroepiandrosteron (DHEA) und seinem Sulfatester DHEA-S vor. Obwohl DHEA und DHEA-S mengenmäßig die bedeutendsten Hormone der menschlichen Nebennierenrinde sind, gehören sie noch nicht zur standardisierten Substitutionstherapie bei Ausfall der Nebennierenrinde. In Untersuchungen der letzten Jahre konnte jedoch wie...

  9. Dem Schreiben Raum geben : eine qualitative Untersuchung zum Einfluss von Angeboten der Peer Schreibberatung auf Regulationsprozesse beim Erstellen einer Abschlussarbeit an der Hochschule

    OpenAIRE

    2011-01-01

    Im Rahmen der vorliegenden Qualifizierungsarbeit von Jantje Witt werden drei Teilnehmende zu ihren Erfahrungen im "Schreibwohnzimmer" befragt. Das "Schreibwohnzimmer" ist eine Initiative der Peer Schreibberatung skript.um der Universität Bielefeld. Es bietet Studierenden Raum, an ihrer Abschlussarbeit zu arbeiten. Im Rahmen dieses Angebots treffen sich etwa 10 Schreibende in Gegenwart einer Peer Schreibtutorin einmalig an drei aufeinander folgenden Tagen. Dort haben sie, gerahmt von einem gem...

  10. Quality Test Various Existing dem in Indonesia Toward 10 Meter National dem

    Science.gov (United States)

    Amhar, Fahmi

    2016-06-01

    Indonesia has various DEM from many sources and various acquisition date spreaded in the past two decades. There are DEM from spaceborne system (Radarsat, TerraSAR-X, ALOS, ASTER-GDEM, SRTM), airborne system (IFSAR, Lidar, aerial photos) and also terrestrial one. The research objective is the quality test and how to extract best DEM in particular area. The method is using differential GPS levelling using geodetic GPS equipment on places which is ensured not changed during past 20 years. The result has shown that DEM from TerraSAR-X and SRTM30 have the best quality (rmse 3.1 m and 3.5 m respectively). Based on this research, it was inferred that these parameters are still positively correlated with the basic concept, namely that the lower and the higher the spatial resolution of a DEM data, the more imprecise the resulting vertical height.

  11. ALGORITHM FOR GENERATING DEM BASED ON CONE

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Digital elevation model (DEM) has a variety of applications in GIS and CAD.It is the basic model for generating three-dimensional terrain feature.Generally speaking,there are two methods for building DEM.One is based upon the digital terrain model of discrete points,and is characterized by fast speed and low precision.The other is based upon triangular digital terrain model,and slow speed and high precision are the features of the method.Combining the advantages of the two methods,an algorithm for generating DEM with discrete points is presented in this paper.When interpolating elevation,this method can create a triangle which includes interpolating point and the elevation of the interpolating point can be obtained from the triangle.The method has the advantage of fast speed,high precision and less memory.

  12. F0F1-ATP-Synthase aus Escherichia coli: Untersuchung verschiedener Proteinsysteme mit ESR-Spektroskopie

    OpenAIRE

    Kraft, Gerhard

    1999-01-01

    Das Enzym F0F1-ATP-Synthase katalysiert die Phosphorylierung von ADP zu ATP unter Ausnutzung des durch die Atmungskette entstehenden Protonengradienten an Membranen. Hierbei pumpt der membranintegrale F0-Teil des Proteins Protonen durch die Membran und induziert die ATP-Synthese, welche auf dem peripheren, wasserlöslichen F1-Teil des Proteins (F1-ATPase) stattfindet. F0 besteht aus drei Proteinuntereinheiten der Stöchiometrie a b_2 c_9-12, während F1 aus fünf Untereinheiten der Stöchiometrie ...

  13. Influence of air pollutants and other factors of stress on phytohormone concentrations in trees. Final report. Pt. 2; Einfluss von Luftschadstoffen und weiteren Stressfaktoren auf Phytohormonkonzentrationen in Baeumen. Abschlussbericht. T. 2

    Energy Technology Data Exchange (ETDEWEB)

    Hock, B.; Schneider, P.; Horn, K.

    1990-04-01

    den Einzelproben zurueckzufuehren. Die gewonnenen Daten des Standortes `Wank` ergaben keine statistisch absicherbaren Zusammenhaenge einer Schaedigung eines Baumes bzw. des Einflusses der Hoehenlage auf den GA-Gehalt. Lediglich Analysen symptomfreier und vergilbter Nadeln belegten einen signifikanten Einfluss auf den Gibberellingehalt, der vermutlich auf eine jahreszeitliche GA{sub 3}-Fluktuation zurueckzufuehren ist. Aus dem vorliegenden Datenmaterial ist eine relevante physiologische Bedeutung der Gibberelline GA{sub 3} und GA{sub 1} fuer eine Fruehindikation von Waldschaeden nicht ableitbar. (orig./UWA)

  14. Magnetic resonance imaging (MRI) of the TMJ: Influence on therapy and inter-observer agreement of two radiologists; Magnetresonanztomographie (MRT) des Kiefergelenkes: Einfluss auf Therapieentscheidung und Uebereinstimmung zweier Auswerter

    Energy Technology Data Exchange (ETDEWEB)

    Vahlensieck, M.; Okweschokwu, S. [Radiologie Haydnhaus, Bonn (Germany); Greven, M. [Medeco Zahnklinik, Bonn (Germany)

    2002-11-01

    Aim: To evaluate the influence of MRI of the temporomandibular joint on the therapeutic strategy in patients with craniomandibular disorders (internal derangement) and, furthermore, to analyze interobserver agreement for defined MRI criteria. Materials and Methods: Fifty-one unilateral and bilateral MRI examinations of 32 patients were enrolled. Therapeutic strategies before and after performance of the MRI were compared. Retrospectively, two radiologists independently analyzed the MR images for position of the disk, position of the condyle, signal intensity of the disk and bilaminar zone, osseous changes and several additional findings, using a check list. Agreement was tested by kappa statistics. Results: In 56% of the cases, changes of the therapeutic regimen were registered after MRI. Statistically significant agreement of the two observers was found for anterior position of the disk (kappa=0.44), transverse position of the disk (kappa=0.46) and position of the condyle (kappa=0.45). No significant agreement was found for signal intensity of the disk (kappa=0.14) or bilaminar zone (kappa=0.24), osseous changes (kappa=0.13) and the additional findings (kappa=0.29). Discussion: MRI has a measurable impact on the therapeutic approach to the internal derangement of the TMJ. The position of the disk and condyle can be reproducibly judged, while the signal intensity of the disk and bilaminar zone and the osseous changes are subject to wide observer variations. (orig.) [German] Zielsetzung: Es sollte der Einfluss der MRT des Kiefergelenkes auf die Therapieentscheidung untersucht werden. Des Weiteren sollten Uebereinstimmungen zweier unabhaengiger Radiologen in der Beurteilung von Kiefergelenk MRT anhand definierter Kriterien bestimmt werden. Material und Methoden: 51 MR-Untersuchungen des Kiefergelenkes wurden ausgewertet. Bei diesen Patienten wurde das urspruengliche mit dem Behandlungskonzept nach MRT verglichen. Alle MRT wurden von zwei Radiologen ausgewertet. Die

  15. The New Global Digital Elevation Model : TanDEM-X DEM and its Final Performance

    Science.gov (United States)

    Gonzalez, Carolina; Rizzoli, Paola; Martone, Michele; Wecklich, Christopher; Borla Tridon, Daniela; Bachmann, Markus; Fritz, Thomas; Wessel, Birgit; Krieger, Gerhard; Zink, Manfred

    2017-04-01

    Digital elevation models (DEMs) have become widely used in many scientific and commercial applications and there are several local products have been developed in the last years. They provide a representation of the topographic features of the landscape. The importance of them is known and valued in every geoscience field, but they have also vast use in navigation and in other commercial areas. The main goal of the TanDEM-X (TerraSARX add-on for Digital Elevation Measurements) mission is the generation of a global DEM, homogeneous in quality with unprecedented global accuracy and resolution, which has been completed in mid-2016. For over four years, the almost identical satellites TerraSAR-X and TanDEM-X acquired single-pass interferometric SAR image pairs, from which is it possible to derive the topographic height by unwrapping the interferometric phase, unaffected by temporal decorrelation. Both satellites have been flying in close formation with a flexible geometric configuration. An optimized acquisition strategy aimed at achieving an absolute vertical accuracy much better than 10 meters and a relative vertical accuracy of 2 m and 4 m for flat and steep terrain, respectively, within a horizontal raster of 12 m x 12 m, which slightly varies depending on the geographic latitude. In this paper, we assess the performance of the global Tandem-X DEM, characterized in terms of relative and absolute vertical accuracy. The coverage statistics are also discussed in comparison to the previous almost global but with lower resolution DEM provided by the Shuttle Radar Topography Mission (SRTM). The exceptional quality of the global DEM is confirmed by the obtained results and the global TanDEM-X DEM is now ready to be distributed to the scientific and commercial community.

  16. Dynamic {sup 31}P-MR-spectroscopy of the quadriceps muscle. Influence of sex and age on spectroscopic results; Die dynamische 31-Phosphor-Magnetresonanz-Spektroskopie des M. quadriceps. Einfluss von Geschlecht und Alter auf spektroskopische Parameter

    Energy Technology Data Exchange (ETDEWEB)

    Schunk, K.; Romaneehsen, B.; Kessler, S.; Schadmand-Fischer, S.; Thelen, M. [Mainz Univ. (Germany). Klinik und Poliklinik fuer Radiologie

    1999-05-01

    ) untersucht. Innerhalb des Magneten wurde der M. quadriceps durch eine isometrische und eine isotonische Uebung jeweils bis zur Erschoepfung belastet. Ergebnisse: Ruhemessung: Mit zunehmendem Alter nahm der Quotient {beta}-Adenosin-triphosphat/Gesamtphosphat (r=-0,37; p=0,02) ab. Die Quotienten anorganisches Phosphat/Phosphokreatin (r=0,79; p=5x10{sup -8}), Phosphomonoester/{beta}-Adenosin-triphosphat (r=0,74; p=10{sup -6}) und Phosphodiester/{beta}-Adenosintriphosphat (r=0,62; p=10{sup -4}) stiegen mit zunehmendem Alter der Probanden an. Der pH-Wert war der einzige der ausgewerteten spektroskopischen Parameter, der eine Abhaengigkeit vom Geschlecht aufwies: Weibliche Probanden zeigten signifikant niedrigere Werte als maennliche (7,03{+-}0,02 vs. 7,05{+-}0,03; p=0,01). Belastungsmessung: Mit zunehmendem Alter waren die belastungsinduzierten Maximalwerte des Quotienten anorganisches Phosphat/Phosphokreatin niedriger (r=-0,42; p=0,0005). Das Ausmass der belastungsinduzierten Azidose war ebenso mit zunehmendem Alter geringer ausgepraegt (r=0,53; p=6x10{sup -6}). Die Erholungsgeschwindigkeit des Quotienten anorganisches Phosphat/Phosphokreatin und des pH-Wertes nach dem erschoepfungsbedingten Ende der Belastung zeigte keine Korrelation mit dem Alter, dem Geschlecht sowie der muskulaeren Querschnittsflaeche des M. quadriceps der jeweiligen Probanden. Schlussfolgerung: Geschlecht und Alter eines Probanden beeinflussen phosphor-spektroskopische Parameter. Dieser Einfluss muss bei der Interpretation phosphorspektroskopischer Studien beruecksichtigt werden. (orig.)

  17. BLAZE-DEM: A GPU based Polyhedral DEM particle transport code

    CSIR Research Space (South Africa)

    Govender, Nicolin

    2013-05-01

    Full Text Available materials for a variety of different geometries. The use of computational modeling tools is essential in evaluation of various designs and processes as computational power increases. However current DEM simulations are only able model a few hundred...

  18. ElevationDEM_DEMHF0p7M2013

    Data.gov (United States)

    Vermont Center for Geographic Information — This metadata applies to the following collection area: Rutland/GI Counties 2013 0.7m and Digital Elevation Model (DEM) datasets of various "hydro-treatments": DEM,...

  19. ElevationDEM_DEMHF1p6M2010

    Data.gov (United States)

    Vermont Center for Geographic Information — This metadata applies to the following collection area(s): Missisquoi Upper 2010 1.6m and Digital Elevation Model (DEM) datasets of various "hydro-treatments": DEM,...

  20. ElevationDEM_DEMHF1p6M2012

    Data.gov (United States)

    Vermont Center for Geographic Information — This metadata applies to the following collection area(s): Addison County 2012 1.6m and Digital Elevation Model (DEM) datasets of various "hydro-treatments": DEM,...

  1. ElevationDEM_DEMHF1p6M2008

    Data.gov (United States)

    Vermont Center for Geographic Information — This metadata applies to the following collection area(s): Missisquoi Lower 2008 1.6m and Digital Elevation Model (DEM) datasets of various "hydro-treatments": DEM,...

  2. Numerical integration - connecting link between theory and practice. Pt. 1. Functionalism and action of numerical mathematical algorithms and their influence to the results of the system performance; Numerische Integration - Bindeglied zwischen Theorie und Praxis. T. 1. Funktionalitaet und Wirken numerischer mathematischer Algorithmen, sowie deren Einfluss auf die Ergebnisse des ``Systemverhaltens``

    Energy Technology Data Exchange (ETDEWEB)

    Rauch, K.C.

    1997-04-01

    The consideration of dynamic processes becomes more and more important on investigations of building heating plants, because of their influence on the economics, but also on the determination of an energy-optimal operation of such a system. For practical considerations of counter-clockwise operated heat exchanger model with known system parameters has been extracted for the theoretical investigations. The first part of this contribution deals with the functionalism and the action of the proposed numerical methods (the kind of finite differencing-scheme, grid spacing of time and space). The second part belongs to the results of the system performance of the technical component. The resulting differences which are produced by the used numerical method will be considered by special investigations of the asymptotik behaviour according to the grid spacing (number of nodes). (orig./GL) [Deutsch] Die Betrachtung dynamischer Vorgaenge spielt zunehmend bei der Untersuchung von Gebaeudewaermeversorgungssystemen eine erhebliche Rolle, da deren Auswirkungen massgeblich die Wirtschaftlichkeit eines Anlagensystems beeinflussen, sowie zur Findung und Beurteilung energieoptimaler Fahrweisen benoetigt werden. Anhand eines konkreten Beispiels (Waermeuebertrager im Gegenstrom) wird auf die speziellen Belange und Eigentuemlichkeiten bei der Modellerstellung (verteilt/konzentriert) sowie die gaengigsten Loesungsansaetze eingegangen und deren Einfluss auf die ermittelten Ergebnisse dargestellt. Der Aufsatz wird dabei in zwei Teile untergliedert. Der erste Teil beschaeftigt sich mit der Funktionalitaet und dem Wirken der vorgestellten numerischen mathematischen Algorithmen, sowie mit den den Loesungsmethoden eigenen Diskretisierungsansaetzen fuer die notwendige Umwandlung der partiellen Differentialquotienten in Differenzenquotienten zur Bildung der gewoehnlichen Differentialgleichungen. Der zweite Teil des Aufsatzes untersucht den Einfluss der beschriebenen numerischen Verfahren auf die

  3. Der Einfluss von rechtsgerichtetem Autoritarismus und sozialer Dominanzorientierung auf homophobe Einstellungen

    Directory of Open Access Journals (Sweden)

    Sarah Andrejewski

    2016-06-01

    Full Text Available Das Thema Homophobie geriet seit 2012 verstärkt in das Interesse der Medien. Ursachen waren u.a. die Erlassung homophober Gesetze in Russland, Outings von prominenten Persönlichkeiten wie Fußballspieler und Politiker oder die in Frankreich auftretenden Massendemonstrationen zur Verhinderung der gleichgeschlechtlichen Ehe. Durch das kürzlich stattfindende Attentat in einem beliebten Club der LGBT-Community in Orlando ist das Thema präsenter denn je. Neben Untersuchungen, die aufdecken, welchen Vorurteilen Menschen mit einer homosexuellen Ausrichtung ausgesetzt sind und wie sich diese im Alltag der Betroffenen niederschlagen, suchen vermehrt Studien nach den Gründen dieser Vorurteile. Die vorliegende Arbeit bedient sich dazu etablierter Konzepte aus der Vorurteilsforschung, um diese in einen Zusammenhang mit homophoben Einstellungen und Verhaltensweisen zu bringen. Mithilfe einer Online-Befragung von 249 heterosexuellen Teilnehmern wurde der Einfluss von rechtsgerichteten Autoritarismus (RWA, sozialer Dominanzorientierung (SDO und sozialer Identität (SI auf homophobe Einstellungen ermittelt. Es konnte nachgewiesen werden, dass die untersuchten Variablen negativ auf die Einstellungen der Untersuchungsteilnehmer gegenüber Schwulen und Lesben wirken. Gleichzeitig wurde die Mediatorrolle der sozialen Identität als Identifikation mit der eigenen heterosexuellen Orientierung getestet und nachgewiesen, dass diese als Mediator zwischen RWA, SDO und homophoben Einstellungen fungiert.

  4. The role of DEM at CERN

    CERN Document Server

    Van der Bij, E

    2005-01-01

    The DEM group in the Technical Support department provides services for the fabrication of special printed circuits that are invaluable for the whole particle physics community. The capability is based around a core technology that is developed by using skills to etch and process materials that are not commonly used in industry, combined with production methods used in PCB manufacturing. The role of the prototyping facilities is to assist engineers and physicists and to offer them easy access to competencies often not available from industry. At the same time, with the expertise and production capacity available, it makes that CERN is always geared up to handle emergency situations. The design office and the assembly workshop that are also part of DEM have similar roles that lower the cost and improve the quality and maintainability of electronics developed at CERN.

  5. Incorporating DEM uncertainty in coastal inundation mapping.

    Directory of Open Access Journals (Sweden)

    Javier X Leon

    Full Text Available Coastal managers require reliable spatial data on the extent and timing of potential coastal inundation, particularly in a changing climate. Most sea level rise (SLR vulnerability assessments are undertaken using the easily implemented bathtub approach, where areas adjacent to the sea and below a given elevation are mapped using a deterministic line dividing potentially inundated from dry areas. This method only requires elevation data usually in the form of a digital elevation model (DEM. However, inherent errors in the DEM and spatial analysis of the bathtub model propagate into the inundation mapping. The aim of this study was to assess the impacts of spatially variable and spatially correlated elevation errors in high-spatial resolution DEMs for mapping coastal inundation. Elevation errors were best modelled using regression-kriging. This geostatistical model takes the spatial correlation in elevation errors into account, which has a significant impact on analyses that include spatial interactions, such as inundation modelling. The spatial variability of elevation errors was partially explained by land cover and terrain variables. Elevation errors were simulated using sequential Gaussian simulation, a Monte Carlo probabilistic approach. 1,000 error simulations were added to the original DEM and reclassified using a hydrologically correct bathtub method. The probability of inundation to a scenario combining a 1 in 100 year storm event over a 1 m SLR was calculated by counting the proportion of times from the 1,000 simulations that a location was inundated. This probabilistic approach can be used in a risk-aversive decision making process by planning for scenarios with different probabilities of occurrence. For example, results showed that when considering a 1% probability exceedance, the inundated area was approximately 11% larger than mapped using the deterministic bathtub approach. The probabilistic approach provides visually intuitive maps

  6. Auf der Suche nach dem Unendlichen.

    Science.gov (United States)

    Fraser, G.; Lillestøl, E.; Sellevåg, I.

    This book is a German translation by C. Ascheron and J. Urbahn, of "The search for infinity: solving the mysteries of the universe", published in 1994. Diese Buch beschreibt anschaulich die Meilensteine, die der Mensch seit der Antike auf der Suche nach dem Unendlichen erreicht und hinter sich gelassen hat. Es enthält Kurzbiographien der wichtigsten Forscher, verständlich geschriebene Texte sowie Erläuterungen der entscheidenen Fachtermini.

  7. Volcanic geomorphology using TanDEM-X

    Science.gov (United States)

    Poland, Michael; Kubanek, Julia

    2016-04-01

    Topography is perhaps the most fundamental dataset for any volcano, yet is surprisingly difficult to collect, especially during the course of an eruption. For example, photogrammetry and lidar are time-intensive and often expensive, and they cannot be employed when the surface is obscured by clouds. Ground-based surveys can operate in poor weather but have poor spatial resolution and may expose personnel to hazardous conditions. Repeat passes of synthetic aperture radar (SAR) data provide excellent spatial resolution, but topography in areas of surface change (from vegetation swaying in the wind to physical changes in the landscape) between radar passes cannot be imaged. The German Space Agency's TanDEM-X satellite system, however, solves this issue by simultaneously acquiring SAR data of the surface using a pair of orbiting satellites, thereby removing temporal change as a complicating factor in SAR-based topographic mapping. TanDEM-X measurements have demonstrated exceptional value in mapping the topography of volcanic environments in as-yet limited applications. The data provide excellent resolution (down to ~3-m pixel size) and are useful for updating topographic data at volcanoes where surface change has occurred since the most recent topographic dataset was collected. Such data can be used for applications ranging from correcting radar interferograms for topography, to modeling flow pathways in support of hazards mitigation. The most valuable contributions, however, relate to calculating volume changes related to eruptive activity. For example, limited datasets have provided critical measurements of lava dome growth and collapse at volcanoes including Merapi (Indonesia), Colima (Mexico), and Soufriere Hills (Montserrat), and of basaltic lava flow emplacement at Tolbachik (Kamchatka), Etna (Italy), and Kīlauea (Hawai`i). With topographic data spanning an eruption, it is possible to calculate eruption rates - information that might not otherwise be available

  8. Effect of the blade design on the dissipation and noise emission of radial blowers; Einfluss der Schaufelform auf Dissipation und Schallemission bei Radialventilatoren. Aerodynamische und akustische Qualitaetsbeurteilung

    Energy Technology Data Exchange (ETDEWEB)

    Sentek, J. [Akademia Gorniczo-Hutnicza, Cracow (Poland); Bommes, L. [Fachhochschule Duesseldorf (Germany). Inst. fuer Stroemungsmaschinen

    2000-04-01

    The flow condition caused within a radial blower by the blade design is known to have a considerable effect both on the hydraulic losses as well as on the level of the emitted noise. (orig.) [German] Der durch die Schaufelform verursachte Stroemungszustand im Inneren eines Radialventilators hat bekanntermassen einen erheblichen Einfluss sowohl auf die hydraulischen Verluste als auch auf die Staerke der Schallabstrahlung. (orig.)

  9. Quality of Life in patiens with Atrial Fibrillation after Catheter Ablation

    OpenAIRE

    Kindsmüller, Sibylle Anne

    2011-01-01

    Ziel der Arbeit war, die Lebensqualität (QoL) von Patienten mit persistierendem und paroxysmalem Vorhofflimmern (VHF) nach einer Katheterablation bezüglich der Ablationsstrategie und dem Einfluss von Alter, Geschlecht und Symptomatik zu vergleichen. 133 Patienten (57,5+/- 9 Jahre, 98 Männer, 87 persistierendes VHF) wurden nach der Art ihres VHF in je zwei verschiedene Ablationsgruppen randomisiert und füllten sowohl vor Ablation als auch 3 Monate danach einen Fragebogen zu ihrer QoL aus. Alle...

  10. TanDEM-X Bistatic SAR Processing

    OpenAIRE

    Balss, Ulrich; Niedermeier, Andreas; Breit, Helko

    2010-01-01

    In June, 2010 the German SAR satellite TanDEM-X (TerraSAR-X-Add-on for Digital Elevation Measurements) will be launched. Together with TerraSAR-X, launched June 15, 2007, it will form the first spaceborne bistatic SAR platform. Usually one of the satellite is transmitting (active satellite), while both are receiving. As both satellites fly in a helix orbit constellation, during a recording a satellite has to be passive, if the other one is close to the line of sight to the observation targ...

  11. Blütenvielfalt auf dem Acker

    OpenAIRE

    Petersen, B.M.

    2011-01-01

    Früher zierten zahlreiche Blüten die Äcker. Heute sind die Äcker weitgehend blütenarm. Damit fehlt den Blütenbesuchern die Nahrungsquelle und den Landwirten die Blütenbestäuber. Blütenvielfalt bietet darüber hinaus noch viele weitere Vorteile - auch für den Landwirt. Das Merkblatt will Mut machen, wieder mehr Blüten- und Artenvielfalt auf den Acker zu bringen. Es liefert dem Landwirt dazu viele Ideen und Entscheidungshilfen.

  12. Influence of VA-mycorrhiza on heavy metal uptake of oat (Avena sativa L.) from soils differing in heavy metal contamination; Einfluss der VA-Mykorrhiza auf die Schwermetallaufnahme von Hafer (Avena sativa L.) in Abhaengigkeit vom Kontaminationsgrad der Boeden

    Energy Technology Data Exchange (ETDEWEB)

    Loth, F.G. [Giessen Univ. (Germany). Inst. fuer Pflanzenernaehrung; Hoefner, W. [Giessen Univ. (Germany). Inst. fuer Pflanzenernaehrung

    1995-12-31

    The heavy metal uptake of mycorrhizal oat-plants (Avena sativa L.) was evaluated in pot experiments with two soils differing in heavy meatl accumulation. The effect of the fungal isolates on the uptake of the immobile metals Zn and Cu differed between the two soils: In the soil `Kleinlinden` mycorrhizal colonization increased heavy metal uptake by up to 37%. In the highly contaminated soil `Muenchen`, mycorrhizal infection lead to a higher uptake (max. 59%) in roots but to a reduced translocation to the aerial plant fractions. The higher uptake of Zn and Cu into the roots was related to the higher heavy metal concentrations in this soil. The Cd uptake showed no difference between the two soils, but was increased in the roots by VAM together with a lower translocation into the shoots. VAM-formation changed the root architecture by increacing the specific root length (m g{sup -1} root dry matter) and the total root length (km per pot). This increased absorbing surface of the roots was a major, but not the only cause for the differences in heavy metal uptake. (orig.) [Deutsch] Die Schwermetallaufnahme mykorrhizierter Hafer-Pflanzen (Avena sativa L.) wurde im Gefaessversuch mit zwei Boeden unterschiedlicher Belastung evaluiert. Der Einfluss der VAM-Pilzisolate auf die Aufnahme der relativ immobilen Metalle Zn und Cu war stark abhaengig vom eingesetzten Boden: Im Versuch mit dem gering belasteten Kleinlindener Boden wurde die Schwermetallaufnahme in den Spross bis zu 37% gesteigert. Die Beimpfung der Pflanzen auf dem hochkontaminierten Boden aus Muenchen fuehrte dagegen zu hoeheren Aufnahmeraten (bis zu 59%) in der Wurzel bei verringerter Translokation in die oberirdischen Pflanzenteile. Das mobile Schwermetall Cd wurde aus beiden Substraten verstaerkt in die infizierten Wurzeln aufgenommen und in vermindertem Mass in den Spross geleitet. Die mykorrhizainduzierte Vergroesserung der speziellen (m g{sup -1} Wurzel-TM) und der absoluten (km pro Gefaess) Wurzellaenge war in

  13. First Bistatic Spaceborne SAR Experiments with TanDEM-X

    OpenAIRE

    Rodriguez-Cassola, Marc; Prats, Pau; Schulze, Daniel; Tous-Ramon, Nuria; Steinbrecher, Ulrich; Marotti, Luca; Nanninni, Matteo; Younis, Marwan; Lopez-Dekker, Paco; Zink, Manfred; Reigber, Andreas; Krieger, Gerhard; Moreira, Alberto

    2011-01-01

    TanDEM-X is a high-resolution interferometric mission with the main goal of providing a global and unprecedentedly accurate digital elevation model (DEM) of the Earth surface by means of single-pass X-band SAR interferometry. Despite its usual quasi-monostatic configuration, TanDEM-X is the first genuinely bistatic SAR system in space. During its monostatic commissioning phase, the system has been mainly operated in pursuit monostatic mode. However, some pioneering bistat...

  14. Teatras popieriaus lape: Egono Schiele’s ekspresionistiniai autoportretai | Das Theater auf dem Papierblatt: zu den expressionistischen Selbstbildnissen von Egon Schiele

    Directory of Open Access Journals (Sweden)

    Dalia Kolytaitė

    2004-01-01

    Full Text Available Im Werk von Egon Schiele ist der Körper (besonders sein eigener mit seinen mannigfaltigen Ausdrucksformen ein zentrales Thema. Die stark ausgeprägte und sehr spezifische Körpersprache entwickelte der Künstler vor dem Spiegel, wovon nicht nur biographische Daten, sondern auch Photos zeugen. Mit dem ausdrucksvollen Variieren seines Körpers präsentiert Schiele seine Neigung zum Wechseln der Identität, der Rollen, des Selbst, wobei er sich gleichzeitig in drei Positionen befindet: des Darstellers, des Regisseurs und des Zuschauers.Als Objekt der Analyse wurden die sechs Selbstbildnisse ausgewählt: „Selbstbildnis mit kariertem Hemd“ (1917, „Der Prediger (Selbstbildnis“ (1913, „Der Kämpfer (Selbstbildnis“ (1913, „Sitzender männlicher Akt (Selbstbildnis“ (1917, „Der Tänzer (Selbstbildnis“ (1911, „Männlicher Halbakt mit rotem Lendentuch (Selbstbildnis“ (1914. Sie stellen verschiedene plastischen Konfigurationen des Körpers im Raum dar. Obwohl diese Bilder in unterschiedlichen Jahren entstanden sind, lassen sich alle sechs Selbstbildnisse aufgrund der ähnlichen Darstellungsweise, Manier und derselben Technik als ein Pantomimestück betrachten. Für eine solche Betrachtungsweise spricht nicht nur die visuelle Assoziation – der Körper in allen Bildern stellt gleichsam stillgestellte Fragmente einer Bewegung dar, wie man dies bei den Photoherausgaben von Pantomimen oder beim Drehen eines Stummfilmes (sie haben ja die gleichen Elemente Bild und Bewegung beobachten kann. Den Anstoß für eine solche Behauptung gibt die Kunstgattung der Pantomime selbst. Sie ist ja „die große schweigende Kunst“, „das Spiel des bewusst bewegten Körpers“, „die Kunst der Form“, und das „Material, aus dem diese Form geschaffen wird, ist der menschliche Körper“. Schieles Selbstbildnisse entsprechen ihren Grundforderungen: dem begrenzten Raum, der Beleuchtung, dem eng am Körper anliegenden Kostüm, der sehr pers

  15. Energy recovery from green wood and waste wood according to the new EEG; Energetische Verwertung von holzigen Gruenabfaellen und Resthoelzern nach dem neuen EEG

    Energy Technology Data Exchange (ETDEWEB)

    Strohmeyer, Anemon [Bundesverband der Altholzaufbereiter und -verwerter e.V., Berlin (Germany)

    2012-11-01

    The EEG has decisive influence on the further development of biomass power plants. Changes in the markets for ligneous green waste and waste wood caused a reconsideration and adaptation of specifications in the EEG 2012. It is assumed that construction of new biomass power plants will slow down with the new regulations and the pressure on utilisation of ligneous biomass will not increase further. Energy recovery from green waste and waste wood is already under strong competition from materials recovery processes and from conventional power plants interested in cocombustion of CO{sub 2}-neutral waste wood. (orig.) [German] Das EEG hat entscheidenden Einfluss auf die Entwicklung des Anlagenparks der Biomassekraftwerke. Die Veraenderung der Maerkte fuer holzartige Gruenabfaelle und Resthoelzer fuehrte dazu, dass die Anreize und Impulse des EEG ueberprueft und angepasst werden mussten. Das EEG 2012 nimmt insoweit wichtige Systemkorrekturen vor. Unter der Geltung des neuen EEG ist daher davon auszugehen, dass der Anlagenpark langsamer wachsen und der Nutzungsdruck auf holzartige Biomasse nicht weiter ansteigen wird. Denn die energetische Verwertung von holzartigen Gruenabfaellen und Resthoelzern steht bereits heute unter erheblichem Konkurrenzdruck durch die stoffliche Verwertung der geeigneten Qualitaeten und durch konventionelle Kraftwerke, die an dem CO{sub 2}-neutral verbrennenden Wertstoff interessiert sind. (orig.)

  16. DETERMINING MINIMUM HIKING TIME USING DEM

    Directory of Open Access Journals (Sweden)

    ZSOLT MAGYARI-SÁSKA

    2012-11-01

    Full Text Available Determining minimum hiking time using DEM. Minimum hiking time calculus can be used to assess the maximum area where a lost person can be. Such area delimitation can help rescue teams to efficiently organize their missions. The two well known walking time rules was used to determine, compare and correlate the obtained result in a test area. The calculated times has a high correlation coefficient which makes possible a precise conversion between Naismith and Tobler walking times. For delimiting the rescue area a graph based modeling from a raster layer was implemented using R environment. The main challenge in such a modeling is the efficient memory management as the use of Dijkstra algorithm on directional costgraph requires high memory resources.

  17. Zusatz- und Weiterqualifikation nach dem Studium

    Science.gov (United States)

    Domnick, Ivonne

    Ist der Bachelor geschafft, stellt sich die Frage nach einer Weiterqualifizierung. Neben einem Einstieg ins Berufsleben kann auch ein Masterstudium eventuell weitere entscheidende Bonuspunkte für den Lebenslauf bringen. Mit Zusatzqualifikationen aus fachfremden Bereichen wie Betriebswirtschaft oder Marketing ist es für Naturwissenschaftler leichter, den Einstieg ins Berufsleben zu schaffen. Viele Arbeitgeber sehen gerade bei Naturwissenschaftlern eine Promotion gerne. Hier sollte genau abgewogen werden, ob sie innerhalb einer bestimmten Zeitspanne zu schaffen ist. Auch nach einem Einstieg in den Job lässt sich der Doktortitel unter Umständen noch nachholen. Ebenso ist eine Weiterbildung neben dem Beruf in Teilzeit oder in einem Fernkurs möglich. Zusätzlich gibt es viele mehrwöchige oder mehrmonatige Kurse privater Anbieter, in denen man BWL-Grundkenntnisse erwerben kann.

  18. Arc ASCII and GeoTiff DEMs of the North-Central California Coast (DEM_#_ASCII and DEM_#_GeoTIFF)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A seamless, 2 meter resolution digital elevation model (DEM) was constructed for the open-coast region of the San Francisco Bay Area (outside of the Golden Gate...

  19. Arc ASCII and GeoTiff DEMs of the North-Central California Coast (DEM_#_ASCII and DEM_#_GeoTIFF)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A seamless, 2 meter resolution digital elevation model (DEM) was constructed for the open-coast region of the San Francisco Bay Area (outside of the Golden Gate...

  20. Which DEM is the best for glaciology? -Evaluation of global-scale DEM products-

    Science.gov (United States)

    Nagai, Hiroto; Tadono, Takeo

    2017-04-01

    Digital elevation models (DEMs) are fundamental geospatial data to study glacier distribution, changes, dynamics, mass balance and various geomorphological conditions. This study evaluates latest global-scale free DEMs in order to clarify their superiority and inferiority in glaciological uses. Three DEMs are now available; the 1-arcsec. product obtained from the Shuttle Radar Topographic Mission (SRTM1), the second version of Global Digital Elevation Model of the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER GDEM2), and the first resampled dataset acquired by the Advanced Land observing Satellite, namely ALOS World 3D-30m (AW3D30). These DEMs have common specifications of global coverage (B>C). In the Tone river basin, SRTM1 has equivalent accuracy to AW3D30. High resolution (2.5 m) of the original stereo-pair images for AW3D30 (i.e. ALOS PRISM imagery) contributes for the best absolute accuracy. Glaciers on rather flat terrains are usually distributed in higher latitude (e.g. Antarctica and Greenland), where SRTM1 is unable. Glaciers at mid-to-low latitudes glaciers are usually distributed in high and steep mountains, where SRTM1 has lower accuracy than AW3D30. AW3D30 would contributes as a preferable option for glaciology in a global scale. At the tops of high mountains in the Nepal Himalaya, however, AW3D30 has a large area of data missing due to snow cover. This inferiority should be improved by filling with other datasets in the next version. ASTER GDEM2 has less area of data missing in the Nepal Himalaya, which would contribute for coarse uses such as generation of river basin, brief drawing of a topographic map, etc.

  1. BlazeDEM3D-GPU A Large Scale DEM simulation code for GPUs

    Science.gov (United States)

    Govender, Nicolin; Wilke, Daniel; Pizette, Patrick; Khinast, Johannes

    2017-06-01

    Accurately predicting the dynamics of particulate materials is of importance to numerous scientific and industrial areas with applications ranging across particle scales from powder flow to ore crushing. Computational discrete element simulations is a viable option to aid in the understanding of particulate dynamics and design of devices such as mixers, silos and ball mills, as laboratory scale tests comes at a significant cost. However, the computational time required to simulate an industrial scale simulation which consists of tens of millions of particles can take months to complete on large CPU clusters, making the Discrete Element Method (DEM) unfeasible for industrial applications. Simulations are therefore typically restricted to tens of thousands of particles with highly detailed particle shapes or a few million of particles with often oversimplified particle shapes. However, a number of applications require accurate representation of the particle shape to capture the macroscopic behaviour of the particulate system. In this paper we give an overview of the recent extensions to the open source GPU based DEM code, BlazeDEM3D-GPU, that can simulate millions of polyhedra and tens of millions of spheres on a desktop computer with a single or multiple GPUs.

  2. Exposure to environmental tobacco smoke in children and its impact on urinary levels of metabolites of polycyclic aromatic hydrocarbons; Einfluss einer Passivrauchbelastung auf die Konzentration von PAK-Metaboliten im Urin von Kindern

    Energy Technology Data Exchange (ETDEWEB)

    Heudorf, U. [Abt. Umweltmedizin und Hygiene, Stadtgesundheitsamt, Frankfurt am Main (Germany); Letzel, S. [Inst. fuer Arbeits- Sozial- und Umweltmedizin der Johannes Gutenberg Univ. Main, Mainz (Germany); Angerer, J.; Drexler, H. [Inst. und Poliklinik fuer Arbeits-, Sozial- und Umweltmedizin der Friedrich-Alexander-Univ. Erlangen-Nuernberg, Erlangen (Germany)

    2001-07-01

    -Gaschromatographie und stickstoffspezifische Detektion) untersucht. Fuer alle Kinder waren Angaben zum Rauchverhalten Dritter in der Wohnung und damit zur Passivrauchbelastung der Kinder zu Hause erhoben worden (Angaben zu Rauchen in der Wohnung: nie, nur auf dem Balkon, selten, regelmaessig). Ergebnisse: Mit zunehmender angegebener Passivrauchbelastung der Kinder zeigte sich eine Tendenz zu einer hoeheren PAK-Metabolitenausscheidung der Kinder, die Unterschiede waren jedoch nicht signifikant (Passivrauchbelastung regelmaessig vs nie: Medianwerte der Summe hydroxylierte Phenanthrene 1194 vs. 1037 ng/g Kreatinin, 1-Hydroxypyren 151 vs. 125 ng/g Kreatinin) Bei den Kindern mit positivem Cotinin-Nachweis im Urin als objektives Zeichen einer Passivrauchbelastung waren signifikant hoehere Konzentrationen an 1-Hydroxypyren im Urin feststellbar (1-Hydroxypyren 197 vs. 144 ng/g Kreatinin, signifikant, p = 0,043); die Spearman-Rank-Korrelation zwischen der Cotinin- und der 1-Hydroxypyren-konzentration im Urin war ebenfalls signifikant (r = 0,197, p = 0,049). Demgegenueber konnte kein Einfluss der Passivrauchbelastung auf die Konzentration der hydroxylierten Phenanthrene im Urin nachgewiesen werden. Schlussfolgerung: Passivrauchen, quantifiziert durch die Cotinin-Ausscheidung im Urin, fuehrt zu einer statistisch signifikanten Zunahme der Ausscheidung von 1-Hydroxypyren, nicht aber der monohydroxylierten Phenanthrene im Urin exponierter Kinder. (orig.)

  3. Modeling Glacier Elevation Change from DEM Time Series

    Directory of Open Access Journals (Sweden)

    Di Wang

    2015-08-01

    Full Text Available In this study, a methodology for glacier elevation reconstruction from Digital Elevation Model (DEM time series (tDEM is described for modeling the evolution of glacier elevation and estimating related volume change, with focus on medium-resolution and noisy satellite DEMs. The method is robust with respect to outliers in individual DEM products. Fox Glacier and Franz Josef Glacier in New Zealand are used as test cases based on 31 Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER DEMs and the Shuttle Radar Topography Mission (SRTM DEM. We obtained a mean surface elevation lowering rate of −0.51 ± 0.02 m·a−1 and −0.09 ± 0.02 m·a−1 between 2000 and 2014 for Fox and Franz Josef Glacier, respectively. The specific volume difference between 2000 and 2014 was estimated as −0.77 ± 0.13 m·a−1 and −0.33 ± 0.06 m·a−1 by our tDEM method. The comparably moderate thinning rates are mainly due to volume gains after 2013 that compensate larger thinning rates earlier in the series. Terminus thickening prevailed between 2002 and 2007.

  4. Hydraulic fracturing - an attempt of DEM simulation

    Science.gov (United States)

    Kosmala, Alicja; Foltyn, Natalia; Klejment, Piotr; Dębski, Wojciech

    2017-04-01

    Hydraulic fracturing is a technique widely used in oil, gas and unconventional reservoirs exploitation in order to enable the oil/gas to flow more easily and enhance the production. It relays on pumping into a rock a special fluid under a high pressure which creates a set of microcracks which enhance porosity of the reservoir rock. In this research, attempt of simulation of such hydrofracturing process using the Discrete Element Method approach is presented. The basic assumption of this approach is that the rock can be represented as an assembly of discrete particles cemented into a rigid sample (Potyondy 2004). An existence of voids among particles simulates then a pore system which can be filled out by fracturing fluid, numerically represented by much smaller particles. Following this microscopic point of view and its numerical representation by DEM method we present primary results of numerical analysis of hydrofracturing phenomena, using the ESyS-Particle Software. In particular, we consider what is happening in distinct vicinity of the border between rock sample and fracking particles, how cracks are creating and evolving by breaking bonds between particles, how acoustic/seismic energy is releasing and so on. D.O. Potyondy, P.A. Cundall. A bonded-particle model for rock. International Journal of Rock Mechanics and Mining Sciences, 41 (2004), pp. 1329-1364.

  5. Amery ice shelf DEM and its marine ice distribution

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The Amery Ice Shelf is the largest ice shelf in East Antarctica. A new DEM was generated for this ice shelf, using kriging to interpolate the data from ICESat altimetry and the AIS-DEM. The ice thickness distribution map is converted from the new DEM, assuming hydrostatic equilibrium. The Amery Ice Shelf marine ice, up to 230 m thick, is concentrated in the northwest of the ice shelf. The volume of the marine ice is 2.38×103 km3 and accounts for about 5.6% of the shelf volume.

  6. Acidente vascular cerebral e demência vascular no idoso

    OpenAIRE

    Ionel, Cristina

    2015-01-01

    Trabalho final de mestrado integrado em Medicina, apresentado à Faculdade de Medicina da Universidade de Coimbra. Em consequência de um fenómeno global de envelhecimento populacional, é expectável um aumento na prevalência de demência. A demência vascular é a segunda causa mais comum de demência, depois da doença de Alzheimer. Trata-se de uma entidade clínica bastante heterogénea, sendo o acidente vascular cerebral (AVC) um dos seus mecanismos subjacentes. No entanto, nem todos os doentes ...

  7. VT Lidar DEM (3.2 meter) - 2004 - Chittenden

    Data.gov (United States)

    Vermont Center for Geographic Information — (Link to Metadata) This metadata applies to the following collection area(s): Chittenden County 2004 3.2m and Digital Elevation Model (DEM) datasets of various...

  8. VT Lidar Hydro-flattened DEM (2 meter) - 2012 - Bennington

    Data.gov (United States)

    Vermont Center for Geographic Information — (Link to Metadata) This metadata applies to the following collection area(s): Bennington County 2012 2.0m and Digital Elevation Model (DEM) datasets of various...

  9. Digital Elevation Models (DEMs) for the main 8 Hawaiian Islands

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Digital elevation model (DEM) data are arrays of regularly spaced elevation values referenced horizontally either to a Universal Transverse Mercator (UTM)...

  10. Digital Elevation Models (DEMs) for the main 8 Hawaiian Islands

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Digital elevation model (DEM) data are arrays of regularly spaced elevation values referenced horizontally either to a Universal Transverse Mercator (UTM) projection...

  11. Orthorectification of IKONOS and Impact of Different Resolution DEM

    Institute of Scientific and Technical Information of China (English)

    XU Junfeng; HUANG Jingfeng

    2006-01-01

    IKONOS image has been wildly used in city planning, precision agriculture and emergence response. However, the accuracy of IKONOS Geo product is limited due to distortion caused by terrain relief. Orthorectification was performed to remove the distortion and the impact of different DEM on orthorectification were evaluated. 38 ground control points (GCPs) and 25 independent check points (ICPs) were collected. DEMs were generated from 1∶10 000 and 1∶50 000 topographic maps. Results show that RMS error at the check points is 1.554 0 m using DEM generated from 1∶10 000 topographic map, which can meet the accuracy requirement of IKONOS Precision product (1.9 m RMSE). While RMS error is 2.572 4 m using DEM generated from 1∶50 000 topographic map.

  12. ElevationDEM_DEMHF0p7M2014

    Data.gov (United States)

    Vermont Center for Geographic Information — This metadata applies to the following collection area(s): Eastern VT 2014 0.7m and Digital Elevation Model (DEM) dataset of the following "hydro-treatment": *DEMHF....

  13. VT USGS NED Hydro-flattened DEM (30 meter) - statewide

    Data.gov (United States)

    Vermont Center for Geographic Information — (Link to Metadata) VTHYDRODEM was created to produce a "hydrologically correct" DEM, compliant with the Vermont Hydrography Dataset (VHD) in support of the "flow...

  14. Digital Elevation Model (DEM), Published in 2007, City of Dubuque.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Digital Elevation Model (DEM) dataset, was produced all or in part from Orthoimagery information as of 2007. Data by this publisher are often provided in State...

  15. High-resolution DEM Effects on Geophysical Flow Models

    Science.gov (United States)

    Williams, M. R.; Bursik, M. I.; Stefanescu, R. E. R.; Patra, A. K.

    2014-12-01

    Geophysical mass flow models are numerical models that approximate pyroclastic flow events and can be used to assess the volcanic hazards certain areas may face. One such model, TITAN2D, approximates granular-flow physics based on a depth-averaged analytical model using inputs of basal and internal friction, material volume at a coordinate point, and a GIS in the form of a digital elevation model (DEM). The volume of modeled material propagates over the DEM in a way that is governed by the slope and curvature of the DEM surface and the basal and internal friction angles. Results from TITAN2D are highly dependent upon the inputs to the model. Here we focus on a single input: the DEM, which can vary in resolution. High resolution DEMs are advantageous in that they contain more surface details than lower-resolution models, presumably allowing modeled flows to propagate in a way more true to the real surface. However, very high resolution DEMs can create undesirable artifacts in the slope and curvature that corrupt flow calculations. With high-resolution DEMs becoming more widely available and preferable for use, determining the point at which high resolution data is less advantageous compared to lower resolution data becomes important. We find that in cases of high resolution, integer-valued DEMs, very high-resolution is detrimental to good model outputs when moderate-to-low (<10-15°) slope angles are involved. At these slope angles, multiple adjacent DEM cell elevation values are equal due to the need for the DEM to approximate the low slope with a limited set of integer values for elevation. The first derivative of the elevation surface thus becomes zero. In these cases, flow propagation is inhibited by these spurious zero-slope conditions. Here we present evidence for this "terracing effect" from 1) a mathematically defined simulated elevation model, to demonstrate the terracing effects of integer valued data, and 2) a real-world DEM where terracing must be

  16. Gesund aufwachsen – Welche Bedeutung kommt dem sozialen Status zu?

    OpenAIRE

    Lampert, Thomas; Kuntz, Benjamin

    2015-01-01

    Deutschland gehört zu den reichsten Ländern der Welt und verfügt über ein gut ausgebautes Sozialversicherungssystem. Dennoch wachsen auch hierzulande nicht alle Kinder und Jugendlichen unter den gleichen Lebensbedingungen auf. Die Ausgabe 1/2015 der Reihe GBE kompakt geht der Frage nach, welche Bedeutung dem sozialen Status beim gesunden Aufwachsen zukommt. Die Autoren untersuchen, ob sich soziale Ungleichheit im Gesundheitszustand, dem Gesundheitsverhalten und der Gesundheitsversorgung von K...

  17. Neues aus dem Forschungsfeld Deutsch als Zweitsprache. Sammelrezension

    Directory of Open Access Journals (Sweden)

    Claus Altmayer

    2015-03-01

    Full Text Available Neues aus dem Forschungsfeld Deutsch als Zweitsprache. Sammelrezension (Teil 2 von Bernt Ahrenholz (Hrsg. (2009, Empirische Befunde zu DaZ-Erwerb und Sprachförderung. Beiträge aus dem 3. ‚Workshop Kinder mit Migrationshintergrund‘; Karen Schramm & Christoph Schröder (Hrsg. (2009, Empirische Zugänge zu Spracherwerb und Sprachförderung in Deutsch als Zweitsprache; Stefan Jeuk (2010, Deutsch als Zweitsprache in der Schule. Grundlagen - Diagnose – Förderung

  18. DEM error retrieval by analyzing time series of differential interferograms

    OpenAIRE

    Bombrun, Lionel; Gay, Michel; Trouvé, Emmanuel; Vasile, Gabriel; Mars, Jerome,

    2009-01-01

    International audience; 2-pass Differential Synthetic Aperture Radar Interferometry (D-InSAR) processing have been successfully used by the scientific community to derive velocity fields. Nevertheless, a precise Digital Elevation Model (DEM) is necessary to remove the topographic component from the interferograms. This letter presents a novel method to detect and retrieve DEM errors by analyzing time series of differential interferograms. The principle of the method is based on the comparison...

  19. AG TURBO, TURBOTECH II - the influence of periodic unsteady inlet flow conditions on the transition behavior of compressor cascades. Final report; AG TURBO, TURBOTECH II: Vorhaben 1.134 - Optimierung des Stroemungsverhaltens von Verdichtergittern mit CDA-Profilierung. Der Einfluss periodisch instationaerer Zustroemung auf das Transitionsverhalten von Verdichtergittern. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Fottner, L.; Teusch, R.; Kampitsch, M.

    2000-09-01

    einer modernen kostenorientierten Schaufelauslegung wird versucht, durch Optimierung der Schaufelprofile unter Beruecksichtigung der obengenannten instationaeren Effekte bei gleichbleibendem Wirkungsgrad und Leistungsverhalten die aerodynamische Schaufelbelastung zu erhoehen, wodurch eine Reduzierung der Schaufelzahl und damit eine kompaktere Bauweise mit geringerem Gewicht ermoeglicht wird. Das Resultat einer diese Effekte beruecksichtigenden Optimierung ist ein aeusserst komplexes, hochgradig dreidimensionales und instationaeres Stroemungsfeld, das hohe Anforderungen an die numerischen Auselgungsverfahren stellt. Primaeres Ziel dieser Arbeit war, durch eine detaillierte Untersuchung des instationaeren Stroemungsverhaltens um Verdichterschaufeln mit CDA-Profilierung unter dem Einfluss von Nachlaufdellen stromaufliegender Schaufelreihen einen tieferen Einblick in die physikalischen Vorgaenge innerhalb der Schaufelgrenzschicht zu ermoeglichen und mit Hilfe der experimtellen Daten instationaere numerische Verfahren zu validieren. Fuer die beiden untersuchten Verdichtergitter V110 und V111 wurde bei niedriger Zustroem-Reynoldszahl eine bis zu 20%-ige Verlustreduzierung und bei hoher Reynoldszahl ein bis zu 30%-iger Verlustanstieg gegenueber dem stationaeren Fall verzeichnet. Die Nachrechnung der experimentellen Ergebnisse mit dem instationaeren Reynolds-gemittelten Navier-Stokes-Verfahren TRACE{sub U} mit Transitionsmodellierung lieferte sehr gute Ergebnisse. Desweiteren wurden Hinweise fuer eine zukuenftige, die instationaeren Effekte beruecksichtigende Schaufelauslegung erteilt. (orig.)

  20. Effect of co- and counter-swirl on the isothermal flow- and mixture field of a double-airflow burner; Einfluss gleich- und gegensinniger Verdrallung auf das isotherme Stroemungs- und Mischungsfeld eines luftseitig zweiflutigen Brenners

    Energy Technology Data Exchange (ETDEWEB)

    Merkle, K.; Haessler, H.; Zarzalis, N. [Universitaet Karslruhe (Germany). Lehrstuhl fuer Verbrennungstechnik

    2002-11-01

    Atomization of liquid fuel in aircraft engines requires application of airblast atomizers, where the kerosene is supplied into the shear layer between two swirling airstreams. The transfer of this functional principle towards gaseous fuel, as illustrated in Fig. 1, yielded a strong influence of the swirl arrangement of the airflows on flame stability and homogeneity of the fuel/air-mixture. Compared to the co-swirl configuration the flow field of the counter-swirl arrangement exhibits a marked increase of the mass flow recirculated in the internal recirculation zone and a reduction of its length in axial direction. This is attributed to the faster decay of tangential velocity maxima in case of counter-rotating airflows. This generates a stronger positive axial pressure gradient dp/dx, thus enhancing the internal recirculation zone. Analysis of local turbulence quantities yields a restriction of turbulent exchange to smaller radial sections and lower maximum values in the jet dominated domain of the flow field in case of counter-swirling airflows. These findings are in good accordance to Rayleigh's criterion, which considers the forces of radial pressure gradient and centrifugal forces acting on a turbulence element deviated from its initial track. Comparison of the mixture fields exhibits faster macro-mixing of fuel and combustion air in case of the co-swirl arrangement. These findings confirm the observation, that turbulent exchange is dampened by application of counter-swirling airflows. (orig.) [German] In der Luftfahrt werden zur Zerstaeubung des fluessigen Brennstoffs ueblicherweise Airblastduesen eingesetzt, d.h. das Kerosin wird in die Scherschicht zweier verdrallter Luftstroeme zugefuehrt. Bei der Uebertragung dieses Konstruktionsprinzips auf gasfoermigen Brennstoff gemaess Bild 1 haben Untersuchungen gezeigt, dass die Drallanordnung grossen Einfluss auf die Flammenstabilitaet und Homogenitaet der Gemischbildung hat. Im Vergleich zu der

  1. Input Data Boundary Outlines for DEMs of the North-Central California Coast (DEM_source_data.shp)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A GIS polygon shapefile outlining the boundaries of the native input datasets used to construct a seamless, 2-meter resolution digital elevation model (DEM) was...

  2. Generating DEM from LIDAR data - comparison of available software tools

    Science.gov (United States)

    Korzeniowska, K.; Lacka, M.

    2011-12-01

    In recent years many software tools and applications have appeared that offer procedures, scripts and algorithms to process and visualize ALS data. This variety of software tools and of "point cloud" processing methods contributed to the aim of this study: to assess algorithms available in various software tools that are used to classify LIDAR "point cloud" data, through a careful examination of Digital Elevation Models (DEMs) generated from LIDAR data on a base of these algorithms. The works focused on the most important available software tools: both commercial and open source ones. Two sites in a mountain area were selected for the study. The area of each site is 0.645 sq km. DEMs generated with analysed software tools ware compared with a reference dataset, generated using manual methods to eliminate non ground points. Surfaces were analysed using raster analysis. Minimum, maximum and mean differences between reference DEM and DEMs generated with analysed software tools were calculated, together with Root Mean Square Error. Differences between DEMs were also examined visually using transects along the grid axes in the test sites.

  3. Local validation of EU-DEM using Least Squares Collocation

    Science.gov (United States)

    Ampatzidis, Dimitrios; Mouratidis, Antonios; Gruber, Christian; Kampouris, Vassilios

    2016-04-01

    In the present study we are dealing with the evaluation of the European Digital Elevation Model (EU-DEM) in a limited area, covering few kilometers. We compare EU-DEM derived vertical information against orthometric heights obtained by classical trigonometric leveling for an area located in Northern Greece. We apply several statistical tests and we initially fit a surface model, in order to quantify the existing biases and outliers. Finally, we implement a methodology for orthometric heights prognosis, using the Least Squares Collocation for the remaining residuals of the first step (after the fitted surface application). Our results, taking into account cross validation points, reveal a local consistency between EU-DEM and official heights, which is better than 1.4 meters.

  4. A comparative analysis of different DEM interpolation methods

    Directory of Open Access Journals (Sweden)

    P.V. Arun

    2013-12-01

    Full Text Available Visualization of geospatial entities generally entails Digital Elevation Models (DEMs that are interpolated to establish three dimensional co-ordinates for the entire terrain. The accuracy of generated terrain model depends on the interpolation mechanism adopted and hence it is needed to investigate the comparative performance of different approaches in this context. General interpolation techniques namely Inverse Distance Weighted, kriging, ANUDEM, Nearest Neighbor, and Spline approaches have been compared. Differential ground field survey has been conducted to generate reference DEM as well as specific set of test points for comparative evaluation. We have also investigated the suitability of Shuttle Radar Topographic Mapper Digital Elevation Mapper for Indian terrain by comparing it with the Survey of India (SOI Digital Elevation Model (DEM. Contours were generated at different intervals for comparative analysis and found SRTM as more suitable. The terrain sensitivity of various methods has also been analyzed with reference to the study area.

  5. The scaling method of specific catchment area from DEMs

    Institute of Scientific and Technical Information of China (English)

    YANG Xin; TANG Guoan; XlAO Chenchao; GAO Yiping; ZHU Shijie

    2011-01-01

    Specific Catchment Area (SCA) is defined as the upstream catchment area of a unit contour.As one of the key terrain parameters,it is widely used in the modeling of hydrology,soil erosion and ecological environment.However,SCA value changes significantly at different DEM resolutions,which inevitably affect terrain analysis results.SCA can be described as the ratio of Catchment Area (CA) and DEM grid length.In this paper,the scale effect of CA is firstly investigated.With Jiuyuangou Gully,a watershed about 70 km2 in northern Shaanxi Province of China,as the test area,it is found that the impacts of DEM scale on CA are different in spatial distribution.CA value in upslope location becomes bigger with the decrease of the DEM resolution.When the location is close to downstream areas the impact of DEM scale on CA is gradually weakening.The scale effect of CA can be concluded as a mathematic trend of exponential decline.Then,a downscaling model of SCA is put forward by introducing the scale factor and the location factor.The scaling model can realize the conversion of SCA value from a coarse DEM resolution to a finer one at pixel level.Experiment results show that the downscaled SCA was well revised,and consistent with SCA at the target resolution with respect to the statistical indexes,histogram and spatial distribution.With the advantages of no empirical parameters,the scaling model could be considered as a simple and objective model for SCA scaling in a rugged drainage area.

  6. Extract relevant features from DEM for groundwater potential mapping

    Science.gov (United States)

    Liu, T.; Yan, H.; Zhai, L.

    2015-06-01

    Multi-criteria evaluation (MCE) method has been applied much in groundwater potential mapping researches. But when to data scarce areas, it will encounter lots of problems due to limited data. Digital Elevation Model (DEM) is the digital representations of the topography, and has many applications in various fields. Former researches had been approved that much information concerned to groundwater potential mapping (such as geological features, terrain features, hydrology features, etc.) can be extracted from DEM data. This made using DEM data for groundwater potential mapping is feasible. In this research, one of the most widely used and also easy to access data in GIS, DEM data was used to extract information for groundwater potential mapping in batter river basin in Alberta, Canada. First five determining factors for potential ground water mapping were put forward based on previous studies (lineaments and lineament density, drainage networks and its density, topographic wetness index (TWI), relief and convergence Index (CI)). Extraction methods of the five determining factors from DEM were put forward and thematic maps were produced accordingly. Cumulative effects matrix was used for weight assignment, a multi-criteria evaluation process was carried out by ArcGIS software to delineate the potential groundwater map. The final groundwater potential map was divided into five categories, viz., non-potential, poor, moderate, good, and excellent zones. Eventually, the success rate curve was drawn and the area under curve (AUC) was figured out for validation. Validation result showed that the success rate of the model was 79% and approved the method's feasibility. The method afforded a new way for researches on groundwater management in areas suffers from data scarcity, and also broaden the application area of DEM data.

  7. O papel da aterosclerose na demência

    OpenAIRE

    Nunes, Ana Luísa da Silva de Sousa

    2015-01-01

    Trabalho final de mestrado integrado em Medicina (Geriatria), apresentado à Faculdade de Medicina da Universidade de Coimbra. Introdução: O aumento progressivo da esperança média de vida, responsável pelo envelhecimento da população, tem promovido o crescimento da prevalência de doenças crónicas e cardiovasculares, como são exemplo a demência e a aterosclerose (ATS), respetivamente. Nos últimos anos, a hipótese de existir uma relação entre a ATS e a demência tem sido alvo de di...

  8. Design flood of ungauged basins based on DEM

    Institute of Scientific and Technical Information of China (English)

    Zhang Ting; Feng Ping

    2012-01-01

    In this paper, the northern mountainous area of Fuzhou City which is an ungauged basin has been taken for example to discuss the method of design flood calculation by means of combining the DEM (digital elevation model) and the Xin' anjiang Model ( three components ). The problem of estimating the parameters of the runoff model has been solved by using the parameters of the reference station. In the conflux calculation, the isochrones are obtained by DEM which helps to avoid the cumbersome work of drawing them on the map. With the establishment of the digital elevation model throughout the country, it is practically significant to use it in the hydrological estimation.

  9. Precise baseline determination for the TanDEM-X mission

    Science.gov (United States)

    Koenig, Rolf; Moon, Yongjin; Neumayer, Hans; Wermuth, Martin; Montenbruck, Oliver; Jäggi, Adrian

    The TanDEM-X mission will strive for generating a global precise Digital Elevation Model (DEM) by way of bi-static SAR in a close formation of the TerraSAR-X satellite, already launched on June 15, 2007, and the TanDEM-X satellite to be launched in May 2010. Both satellites carry the Tracking, Occultation and Ranging (TOR) payload supplied by the GFZ German Research Centre for Geosciences. The TOR consists of a high-precision dual-frequency GPS receiver, called Integrated GPS Occultation Receiver (IGOR), and a Laser retro-reflector (LRR) for precise orbit determination (POD) and atmospheric sounding. The IGOR is of vital importance for the TanDEM-X mission objectives as the millimeter level determination of the baseline or distance between the two spacecrafts is needed to derive meter level accurate DEMs. Within the TanDEM-X ground segment GFZ is responsible for the operational provision of precise baselines. For this GFZ uses two software chains, first its Earth Parameter and Orbit System (EPOS) software and second the BERNESE software, for backup purposes and quality control. In a concerted effort also the German Aerospace Center (DLR) generates precise baselines independently with a dedicated Kalman filter approach realized in its FRNS software. By the example of GRACE the generation of baselines with millimeter accuracy from on-board GPS data can be validated directly by way of comparing them to the intersatellite K-band range measurements. The K-band ranges are accurate down to the micrometer-level and therefore may be considered as truth. Both TanDEM-X baseline providers are able to generate GRACE baselines with sub-millimeter accuracy. By merging the independent baselines by GFZ and DLR, the accuracy can even be increased. The K-band validation however covers solely the along-track component as the K-band data measure just the distance between the two GRACE satellites. In addition they inhibit an un-known bias which must be modelled in the comparison, so the

  10. Entwicklungsperspektiven von Social Software und dem Web 2.0

    Science.gov (United States)

    Raabe, Alexander

    Der Artikel beschäftigt sich zunächst mit dem derzeitigen und zukünftigen Einsatz von Social Software in Unternehmen. Nach dem großen Erfolg von Social Software im Web beginnen viele Unternehmen eigene Social Software-Initiativen zu entwickeln. Der Artikel zeigt die derzeit wahrgenommenen Einsatzmöglichkeiten von Social Software im Unternehmen auf, erörtert Erfolgsfaktoren für die Einführung und präsentiert mögliche Wege für die Zukunft. Nach der Diskussion des Spezialfalles Social Software in Unternehmen werden anschließend die globalen Trends und Zukunftsperspektiven des Web 2.0 in ihren technischen, wirtschaftlichen und sozialen Dimensionen dargestellt. Wie aus den besprochenen Haupttrends hervorgeht, wird die Masse an digital im Web verfügbaren Informationen stetig weiterwachsen. So stellt sich die Frage, wie es in Zukunft möglich sein wird, die Qualität der Informationssuche und der Wissensgenerierung zu verbessern. Mit dem Einsatz von semantischen Technologien im Web wird hier eine revolutionäre Möglichkeit geboten, Informationen zu filtern und intelligente, gewissermaßen verstehende" Anwendungen zu entwerfen. Auf dem Weg zu einem intelligenten Web werden sich das Semantic Web und Social Software annähern: Anwendungen wie Semantic Wikis, Semantic Weblogs, lightweight Semantic Web-Sprachen wie Microformats oder auch kommerzielle Angebote wie Freebase von Metaweb werden die ersten Vorzeichen einer dritten Generation des Webs sein.

  11. Wie ich mich mit dem äthiopischen Regime anlegte

    DEFF Research Database (Denmark)

    Hagmann, Tobias

    2016-01-01

    Als Forscher und Kritiker der äthiopischen Politik habe ich viel über das Verhältnis gelernt, in dem Wahrheit und Macht, aber auch Moral und persönliche Interessen zueinander stehen. In den Niederungen der Realpolitik wird mit harten Bandagen um die Deutungshoheit gekämpft wird. Auch Wissenschafter...

  12. Evaluation of the delirium early monitoring system (DEMS)

    NARCIS (Netherlands)

    Rippon, Daniel; Milisen, Koen; Detroyer, Elke; Mukaetova-Ladinska, Elizabeta; Harrison, Beth; Schuurmans, Marieke; Pryor, Claire; Teodorczuk, Andrew

    2016-01-01

    Background: Despite awareness of the negative health and financial outcomes of delirium, systems to routinely assess and manage the condition are absent in clinical practice. We report the development and pilot evaluation of a Delirium Early Monitoring System (DEMS), designed to be completed by

  13. Packing of non-spherical aggregate particles by DEM

    NARCIS (Netherlands)

    Stroeven, P.; He, H.

    2013-01-01

    Loose random and dense random mono-size paclDEM) for eight types of polyhedral grains, for ellipses with different aspect ratio, for cubes and for spheres. Focus was on density, sphericity of the grains and average value and frequency

  14. Ueber Einige Scyphomedusen aus dem Zoologischen Museum in Amsterdam

    NARCIS (Netherlands)

    Stiasny, G.

    1929-01-01

    Die kleine Scyphomedusen-Sammlung aus dem Zoologischen Museum in Amsterdam, über welche hier kurz berichtet wird, enthält keine neuen Formen. Sie ist jedoch bemerkenswert, weil einzelne bekannte Medusen in zahlreichen Exemplaren vorliegen, die sonst stets nur vereinzelt in den Sammlungen vertreten s

  15. Spatial Characterization of Landscapes through Multifractal Analysis of DEM

    Directory of Open Access Journals (Sweden)

    P. L. Aguado

    2014-01-01

    Full Text Available Landscape evolution is driven by abiotic, biotic, and anthropic factors. The interactions among these factors and their influence at different scales create a complex dynamic. Landscapes have been shown to exhibit numerous scaling laws, from Horton’s laws to more sophisticated scaling of heights in topography and river network topology. This scaling and multiscaling analysis has the potential to characterise the landscape in terms of the statistical signature of the measure selected. The study zone is a matrix obtained from a digital elevation model (DEM (map 10 × 10 m, and height 1 m that corresponds to homogeneous region with respect to soil characteristics and climatology known as “Monte El Pardo” although the water level of a reservoir and the topography play a main role on its organization and evolution. We have investigated whether the multifractal analysis of a DEM shows common features that can be used to reveal the underlying patterns and information associated with the landscape of the DEM mapping and studied the influence of the water level of the reservoir on the applied analysis. The results show that the use of the multifractal approach with mean absolute gradient data is a useful tool for analysing the topography represented by the DEM.

  16. Evaluating DEM results with FEM perspectives of load : soil interaction

    NARCIS (Netherlands)

    Tadesse, D.

    2004-01-01

    Keywords: Load - soil interaction, soil structure, soil mechanical properties, FEM (Finite Element Method), Plaxis (Finite Element Code), granular particles, shear stress, DEM (Distinct Element Method), mic

  17. A 30 meter Digital Elevation Model (DEM) of the San Gorgonio Pass area, Riverside County, California.

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Digital Elevation Models (DEMs) are digital records of terrain elevations at regularly spaced intervals. The interval between elevations of 7.5 minute DEMs is...

  18. Validation of the GPU based BLAZE-DEM framework for hopper discharge

    CSIR Research Space (South Africa)

    Govender, Nicolin

    2015-09-01

    Full Text Available method (DEM) has become the defacto standard to simulate particulate materials. The DEM is a computationally intensive numerical approach that is limited to a moderate amount (thousands) of particles when considering fully coupled densely packed systems...

  19. DEM generated from InSAR in mountainous terrain and its accuracy analysis

    Science.gov (United States)

    Hu, Hongbing; Zhan, Yulan

    2011-02-01

    Digital Elevation Model (DEM) derived from survey data is accurate but it is very expensive and time-consuming. In recent years, remote sensing techniques including Synthetic Apenture Radar Interferometry (InSAR) had been developed as a powerful method to derive high precision DEM, especially in mountainous or deep forest areas. The purpose of this paper is to illustrate the principle of InSAR and show the result of a case study in Gejiu city, Yunnan province, China. The accuracy of DEM derived from InSAR (abbreviation as InSAR-DEM) is also evaluated by comparing it with DEM generated from topographic map at the scale of 1:50000 (abbreviation as TOP-DEM). The result shows that: (1)The general precision of the whole selected area acquired by subtracting InSAR-DEM from TOP-DEM is that the maximum, the minimum, the RMSE, and the mean of difference of the two DEMs are 203m, -188m, 26.9m and 5.7m respectively. (2)The topographic trend represented by the two DEMs is coincident, even though TOP-DEM is finer than InSAR-DEM, especial at the valley. (3) Contour maps with the interval of 100m and 50m converted from InSAR-DEM and TOP-DEM respectively show accordant relief trend. Contour from TOP-DEM is smoother than that of from InSAR-DEM, while Contour from InSAR-DEM has more islands than that of from TOP-DEM.(4) Coherence has great influence on the precision of InSAR-DEM, the precision of low-coherence area approaches 100 m while that of high-coherence area can up to m level. (5) The relief trend of 6 profiles represented by InSAR-DEM and TOP-DEM is accordant with tiny difference in partial minutiae. InSAR-DEM displays hypsographies at relative flat areas including surface of water, which reflects the influence of flat earth on InSAR to a certain extent.

  20. Die Rolle der Glukosetransporter an der Blut-Hirn-Schranke nach einem Schädel-Hirn-Trauma und deren eventueller Einfluss auf die Entwicklung eines sekundären Hirnödems

    OpenAIRE

    Wais, Sebastian

    2013-01-01

    Laut der Weltgesundheitsorganisation (WHO) waren in Deutschland 2006 akute ischämische Ereignisse des Zentralen Nervensystems (ZNS) die fünfthäufigste Todesursache. Zu diesen ischämischen Ereignissen zählen Schlaganfall, Kardiopulmonale Reanimation, traumatische Hirnverletzungen, sowie perioperative ischämische Komplikationen. Aufgrund der schwerwiegenden Folgen, die ein Verlust von Nervenzellen für den Patienten bedeutet, muss die weitere medizinische Akutversorgung den sekundären neuronalen...

  1. Successful face end position according to optimised support concept at the Walsum colliery; Erfolgreiche Strebendstellung nach optimiertem Ausbaukonzept auf dem Bergwerk Walsum

    Energy Technology Data Exchange (ETDEWEB)

    Maucher, B.; Rosinski, D. [Bergbau AG Niederrhein, Duisburg (Germany). Bergwerk Walsum; Mogk, E.; Kulassek, M. [Bergamt Moers (Germany)

    1999-08-30

    For the first time in the German coal mining industry a face end position at the Walsum colliery was supported by the cable bolting method in 1997. The advantages of this system compared to the conventional support method are a prop-free exit track, a high degree of safety and improved ergonomics. The experience acquired during initial use has been incorporated in the support concept of the subsequent panel. In the final position of panel P-91 the bolted area was enlarged, the number and length of the bolts optimised and control of the roof improved by various additional measures. The exit track supported by the cable bolting method permitted the use of a mobile salvaging machine to recover conveyors and shield supports. Recovery performances of up to ten shields per shift or 1.43 shields per man shift were achieved. All work was completed without notifiable accidents. (orig.) [German] Erstmalig im deutschen Steinkohlenbergbau wurde im Jahr 1997 eine Strebendstellung auf dem Bergwerk Walsum in Seilankertechnik ausgebaut. Als Vorteile gegenueber der konventionellen Ausbautechnik bietet diese Technik eine stempelfreie Ausfahrgasse, ein hohes Mass an Arbeitssicherheit und eine verbesserte Ergonomie. Die beim Ersteinsatz gewonnenen Erfahrungen sind in das Ausbaukonzept der Nachfolgebauhoehe eingeflossen. In der Endstellung der Bauhoehe P-91 wurden die geankerte Flaeche vergroessert, die Anzahl und Laenge der Anker optimiert und durch verschiedene zusaetzliche Massnahmen die Beherrschung des Hangenden verbessert. Die in Seilankertechnik ausgebaute Ausfahrgasse erlaubte den Einsatz eines mobilen Raubgeraets zur Wiedergewinnung von Foerderer und Schildausbau. Auf diese Weise wurden Wiedergewinnungsleistungen von bis zu zehn Schilden pro Schicht beziehungsweise 1,43 Schilden/MS erreicht. Alle Arbeiten konnten ohne meldepflichtige Unfaelle abgeschlossen werden. (orig.)

  2. Non-destructive testing of concrete structures with the impact-echo method; Zerstoerungsfreie Pruefung von Betonbauteilen mit dem Impact-Echo-Verfahren

    Energy Technology Data Exchange (ETDEWEB)

    Algernon, Daniel; Feistkorn, Sascha; Scherrer, Michael [SVTI Schweizerischer Verein fuer technische Inspektionen, Wallisellen (Switzerland). Nuklearinspektorat

    2016-05-01

    The impact-echo method is based on the use of elastic waves. It was developed in the 1980 for the testing of concrete structures and is currently widespread. Main application areas are the component and coating thickness measurement and detection of delaminations, voids and other defects. Specifically, the method is also used to check the injection faults of clamping channels. Another application is the determination of mechanical material parameters such as the modulus of elasticity. Since the original development of the method has undergone several enhancements. The conversion of a single-point measurement method towards a area component testing, the use by the optimized measurement data acquisition and evaluation enlarged and delivered an important prerequisite for increasing the efficiency. The use of air-coupled sensors not only increases the measurement speed but also provides advantages in rough component surfaces. The imaging analysis in conjunction with signal processing algorithms simplifies the interpretation and allows statistical evaluation. [German] Das Impact-Echo-Verfahren beruht auf der Nutzung elastischer Wellen. Es wurde in den 1980er Jahren fuer die Pruefung von Stahlbetonbauteilen entwickelt und ist derzeit weit verbreitet. Haupteinsatzgebiete sind die Bauteil- und Schichtdickenmessung sowie die Detektion von Delaminationen, Hohl- und anderen Fehlstellen. Insbesondere wird das Verfahren auch zur Pruefung des Verpresszustandes von Spannkanaelen herangezogen. Eine weitere Anwendung ist die Bestimmung mechanischer Materialparameter wie dem Elastizitaetsmodul. Seit der urspruenglichen Entwicklung hat das Verfahren verschiedene Weiterentwicklungen erfahren. Die Ueberfuehrung von einem Einzelpunktmessverfahren hin zu einer flaechigen Bauteilpruefung hat die Einsatzmoeglichkeiten durch die optimierte Messdatenaufnahme und -auswertung vergroessert und eine wichtige Voraussetzung zur Erhoehung der Leistungsfaehigkeit geliefert. Der Einsatz

  3. Evaluation of lidar-derived DEMs through terrain analysis and field comparison

    Science.gov (United States)

    Cody P. Gillin; Scott W. Bailey; Kevin J. McGuire; Stephen P. Prisley

    2015-01-01

    Topographic analysis of watershed-scale soil and hydrological processes using digital elevation models (DEMs) is commonplace, but most studies have used DEMs of 10 m resolution or coarser. Availability of higher-resolution DEMs created from light detection and ranging (lidar) data is increasing but their suitability for such applications has received little critical...

  4. The TanDEM-X Digital Elevation Model and Terrestrial Impact Craters

    OpenAIRE

    Gottwald, Manfred; Fritz, Thomas; Breit, Helko; Schättler, Birgit; Harris, Alan

    2014-01-01

    We use the global digital elevation model (DEM) generated in the TanDEM-X mission for mapping further confirmed terrestrial impact craters. This DEM provides the most accurate spaceborne global elevation data. It permits detailed studies of the topography of the sites of simple and complex structures with unprecedented accuracy.

  5. Generation of Statewide DEMs and Orthoimages – Guidelines and Methodology

    Directory of Open Access Journals (Sweden)

    Giribabu Dandabathula

    2015-06-01

    Full Text Available Cartosat-1 is a global, high resolution stereographic imaging mission to support enhanced applications in several areas of terrain mapping, natural resources management, disaster management, infrastructure and development planning. A collaborative project of generating statewide Digital Elevation Model (DEMs and mosaic of Ortho-image for all the states and union territories in India has completed under the project namely Space based Information Support for Decentralized Planning (SIS-DP using Photogrammetric techniques with Cartosat-1 stereo data.  Approximately 11000 stereo pairs of Cartosat-1 data were used in this process. Photogrammetric blocks for each state were processed using existing reference tiles and accordingly ortho-images were generated. The paper outlines the methodology for generating state-wide Digital Elevation Models (DEMs and ortho-images. The guidelines that govern the quality of the output were discussed. Dissemination mechanism via public accessible web platform was described.

  6. Characterization of artificial spherical particles for DEM validation studies

    Institute of Scientific and Technical Information of China (English)

    Ignazio Cavarretta; Catherine O'Sullivan; Erdin Ibraim; Martin Lings; Simon Hamlin; David Muir Wood

    2012-01-01

    This paper describes a study in which advanced particle-scale characterization was carried out on spherical particles that can be used in experimental tests to validate discrete element method (DEM) simulations,Two types of particle,alkaline and borosilicate glass heads,made from two different materials,were considered.The particle shape,stiffness,contact friction properties and surface roughness were measured.The influences of hardness and roughness on the mechanical response of the particles were carefully considered.Compared to the alkaline beads,the borosilicate beads were more spherical and more uniform in size,and they exhibited mechanical characteristics closer to natural quartz sand.While only two material types were studied,the work has the broader implication as a methodology for selecting particles suitable for use in DEM studies and the key parameters that should be considered in the selection process are highlighted.

  7. Die Republik Moldau ein Jahr nach dem Wahlsieg der Kommunisten

    OpenAIRE

    Buzogány, Aron

    2002-01-01

    Analyse der politischen, sozialen und ökonomischen Ereignisse in der Republik Moldau, welche nach dem Wahlsieg der Kommunistischen Partei im Jahr 2001 stattgefunden haben. Der Beitrag untersucht Bereiche wie das politische Institutionengefüge, die administrativen Reformen, die Freiheit der Medien, die Wirtschaftsentwicklung sowie die Entwicklung der Beziehungen zwischen der territorialen Autonomie in Gagauzien und der sezessionistischen Quasi-Republik Transnistrien und der Zentralregierung in...

  8. Mapping debris-flow hazard in Honolulu using a DEM

    Science.gov (United States)

    Ellen, Stephen D.; Mark, Robert K.; ,

    1993-01-01

    A method for mapping hazard posed by debris flows has been developed and applied to an area near Honolulu, Hawaii. The method uses studies of past debris flows to characterize sites of initiation, volume at initiation, and volume-change behavior during flow. Digital simulations of debris flows based on these characteristics are then routed through a digital elevation model (DEM) to estimate degree of hazard over the area.

  9. DEM analysis of FOXSI-2 microflare using AIA observations

    Science.gov (United States)

    Athiray Panchapakesan, Subramania; Glesener, Lindsay; Vievering, Juliana; Camilo Buitrago-Casas, Juan; Christe, Steven; Inglis, Andrew; Krucker, Sam; Musset, Sophie

    2017-08-01

    The second flight of Focusing Optics X-ray Solar Imager (FOXSI) sounding rocket experiment was successfully completed on 11 December 2014. FOXSI makes direct imaging and spectral observation of the Sun in hard X-rays using grazing incidence optics modules which focus X-rays onto seven focal plane detectors kept at a 2m distance, in the energy range 4 to 20 keV, to study particle acceleration and coronal heating. Significant HXR emissions were observed by FOXSI during microflare events with A0.5 and A2.5 class, as classified by GOES, that occurred during FOXSI-2 flight.Spectral analysis of FOXSI data for these events indicate presence of plasma at higher temperatures (>10MK). We attempt to study the plasma content in the corona at different temperatures, characterized by the differential emission measure (DEM), over the FOXSI-2 observed flare regions using the Atmospheric Imaging Assembly (SDO/AIA) data. We utilize AIA observations in different EUV filters that are sensitive to ionized iron lines, to determine the DEM by using a regularized inversion method. This poster will show the properties of hot plasma as derived from FOXSI-2 HXR spectra with supporting DEM analysis using AIA observations.

  10. A simplified DEM numerical simulation of vibroflotation without backfill

    Science.gov (United States)

    Jiang, M. J.; Liu, W. W.; He, J.; Sun, Y.

    2015-09-01

    Vibroflotation is one of the deep vibratory compaction techniques for ground reinforcement. This method densities the soil and improves its mechanical properties, thus helps to protect people's lives and property from geological disasters. The macro reinforcement mechanisms of vibroflotation method have been investigated by numerical simulations, laboratory and in-situ experiments. However, little attention has been paid on its micro - mechanism, which is essential to fully understand the principle of the ground reinforcement. Discrete element method (DEM), based on discrete mechanics, is more powerful to solve large deformation and failure problems. This paper investigated the macro-micro mechanism of vibroflotation without backfill under two conditions, i.e., whether or not the ground water was considered, by incorporating inter-particle rolling resistance model in the DEM simulations. Conclusions obtained are as follows: The DEM simulations incorporating rolling resistance well replicate the mechanical response of the soil assemblages and are in line with practical observations. The void ratio of the granular soil fluctuates up and down in the process of vibroflotation, and finally reduces to a lower value. It is more efficient to densify the ground without water compared to the ground with water.

  11. Validation of DEM prediction for granular avalanches on irregular terrain

    Science.gov (United States)

    Mead, Stuart R.; Cleary, Paul W.

    2015-09-01

    Accurate numerical simulation can provide crucial information useful for a greater understanding of destructive granular mass movements such as rock avalanches, landslides, and pyroclastic flows. It enables more informed and relatively low cost investigation of significant risk factors, mitigation strategy effectiveness, and sensitivity to initial conditions, material, or soil properties. In this paper, a granular avalanche experiment from the literature is reanalyzed and used as a basis to assess the accuracy of discrete element method (DEM) predictions of avalanche flow. Discrete granular approaches such as DEM simulate the motion and collisions of individual particles and are useful for identifying and investigating the controlling processes within an avalanche. Using a superquadric shape representation, DEM simulations were found to accurately reproduce transient and static features of the avalanche. The effect of material properties on the shape of the avalanche deposit was investigated. The simulated avalanche deposits were found to be sensitive to particle shape and friction, with the particle shape causing the sensitivity to friction to vary. The importance of particle shape, coupled with effect on the sensitivity to friction, highlights the importance of quantifying and including particle shape effects in numerical modeling of granular avalanches.

  12. Empirische Analyse einer verdolmetschten Gerichtsverhandlung aus dem Slowenischen ins Deutsche

    Directory of Open Access Journals (Sweden)

    Lea Burjan

    2012-12-01

    Full Text Available Dieser Artikel befasst sich mit dem Diskurs in einer Gerichtsverhandlung mit verschiedensprachigen Parteien. Die übliche Konversation im Gerichtssaal findet in Form eines Dialogs statt, wobei die Strategie des Gespräches durch den Richter als Gesprächsmoderator determiniert wird. Die Interaktion im gedolmetschten Diskurs verläuft anders als im nicht gedolmetschten Diskurs. Bei gedolmetschten Verhandlungen übernimmt der Gerichtsdolmetscher, als ein Mittler in der Konversation, die verantwortungsvolle Aufgabe, die richterliche Strategie der Konversation, also den eigentlichen Verhandlungsablauf, sinngemäß und originaltreu in den zielsprachlichen Kontextzu transportieren. Meistert er seine Aufgabe, wird ein reibungsloser Kommunikationsablauf im Sinne der gegenseitigen Einflussnahme der jeweiligen Kommunikationsteilnehmer gewährleistet. Scheitert er bei seinem Vorhaben, so kommt es in der Kommunikation zu Störungen, die durch zusätzliche sprachliche Interventionen beseitigt werden müssen. Seine Tätigkeit wird determiniert und mitbeeinflusst von den Unterschieden in der Rechtsterminologie der beiden Sprachen (Sprachregister, von dem vorgegebenen Dolmetschmodus, und von der Gesprächsstrategie des Sprachmoderators. Somit ist das Ziel des vorliegenden Beitrags, anhand einer empirischen Analyse einer gedolmetschten Zeugenvernehmung herauszufinden, inwiefern es dem Gerichtsdolmetscher gelingt, den ausgangssprachlichen Diskurs originaltreu in die Zielsprache zu übertragen und auf welche Probleme er bei diesem Übertragungsprozess stößt. Der vorliegenden Untersuchung dienen die von den Gerichten veranlassten Audioaufnahmen von mündlichen Verhandlungen als Korpus.

  13. Assoziation von funktionell wirksamen Polymorphismen auf dem humanen Chromosom 1 mit der Pathogenese der chronischen Parodontitis

    OpenAIRE

    Fotiadou, Christina

    2016-01-01

    Die chronische Parodontitis und weitere chronisch entzündliche Erkrankungen, wie Morbus Crohn, stellen komplexe multifaktorielle Krankheiten dar. Obwohl pathogene Bakterien und verschiedene Umweltfaktoren bei der Pathogenese der Parodontitis mitwirken, können diese nur einen Teil der Variabilität innerhalb von definierten Populationen der Erkrankung erklären. So spielen genetische Faktoren eine wichtige Rolle bei der Entstehung einer chronischen Parodontitis. In dieser Arbeit wurden die P...

  14. A Global Corrected SRTM DEM Product Over Vegetated Areas Using LiDAR Data

    Science.gov (United States)

    Zhao, X.; Guo, Q.; Su, Y.; Hu, T.

    2016-12-01

    The Shuttle Radar Topography Mission (SRTM) digital elevation model (DEM) is one of the most complete and frequently used global-scale DEM products in various applications. However, previous studies have shown that the SRTM DEM is systematically higher than the actual land surface in vegetated mountain areas. The objective of this study is to propose a procedure to calibrate the SRTM DEM over global vegetated mountain areas. To address this, we firstly collected airborne LiDAR data over 200,000 km2 globally used as ground truth data to analyze the uncertainty of the SRTM DEM. The Geoscience Laser Altimeter System (GLAS)/ICESat (Ice, Cloud, and land Elevation Satellite) data were used as complementary data in areas lack of airborne LiDAR data. Secondly, we modelled the SRTM DEM error for each vegetation type using regression methods. Tree height, canopy cover, and terrain slope were used as dependent variables to model the SRTM DEM error. Finally, these regression models were used to estimate the SRTM DEM error in vegetated mountain areas without LiDAR data coverage, and therefore correct the SRTM DEM. Our results show that the new corrected SRTM DEM can significantly reduce the systematic bias of the SRTM DEM in vegetated mountain areas.

  15. Modelling above Ground Biomass in Tanzanian Miombo Woodlands Using TanDEM-X WorldDEM and Field Data

    Directory of Open Access Journals (Sweden)

    Stefano Puliti

    2017-09-01

    Full Text Available The use of Interferometric Synthetic Aperture Radar (InSAR data has great potential for monitoring large scale forest above ground biomass (AGB in the tropics due to the increased ability to retrieve 3D information even under cloud cover. To date; results in tropical forests have been inconsistent and further knowledge on the accuracy of models linking AGB and InSAR height data is crucial for the development of large scale forest monitoring programs. This study provides an example of the use of TanDEM-X WorldDEM data to model AGB in Tanzanian woodlands. The primary objective was to assess the accuracy of a model linking AGB with InSAR height from WorldDEM after the subtraction of ground heights. The secondary objective was to assess the possibility of obtaining InSAR height for field plots when the terrain heights were derived from global navigation satellite systems (GNSS; i.e., as an alternative to using airborne laser scanning (ALS. The results revealed that the AGB model using InSAR height had a predictive accuracy of R M S E = 24.1 t·ha−1; or 38.8% of the mean AGB when terrain heights were derived from ALS. The results were similar when using terrain heights from GNSS. The accuracy of the predicted AGB was improved when compared to a previous study using TanDEM-X for a sub-area of the area of interest and was of similar magnitude to what was achieved in the same sub-area using ALS data. Overall; this study sheds new light on the opportunities that arise from the use of InSAR data for large scale AGB modelling in tropical woodlands.

  16. Prevention, screening and therapy of thyroid diseases and their cost-effectiveness; Praevention, Screening und Therapie gutartiger Schilddruesenerkrankungen unter dem Aspekt von Kosten und Nutzen

    Energy Technology Data Exchange (ETDEWEB)

    Dietlein, M.; Moka, D.; Schmidt, M.; Theissen, P.; Schicha, H. [Koeln Univ. (Germany). Klinik und Poliklinik fuer Nuklearmedizin

    2003-10-01

    60%. (orig.) [German] Kosten/Nutzenanalysen in Bezug auf gutartige Schilddruesenerkrankungen sind in der Literatur unterrepraesentiert. Insbesondere die Erhebung eines Geldwertes pro gewonnenem Lebensjahr gestaltet sich methodisch schwierig: Der Nutzen praeventiver Massnahmen ist weit in die Zukunft verlagert. Der Einfluss einer unbehandelten Schilddruesenerkrankung auf die Lebenszeit wird ebenfalls erst durch einen langfristigen Horizont und dann eher epidemiologisch als individuell zu erfassen sein. Als Prophylaxe (primaere Praevention) sind Programme zum Ausgleich des Iodmangels sowie die Aufklaerung ueber den negativen Einfluss des Rauchens auf die Entwicklung einer Struma oder eines M. Basedows aus entscheidungstheoretischer Sicht sehr kosteneffektiv. Screening-Programme (sekundaere Praevention) werden fuer die Parameter TSH, Calcium und Calcitonin diskutiert. Eine besonders guenstige Kosten-Effektivitaet des TSH-Screenings ist in besonderen Lebensphasen (Neugeborene, Schwangerschaft, postpartal, hoeheres Alter, stationaerer Patient mit akuter Erkrankung) und bei definierten Vorbefunden (TSH>2mU/l, TPO-Antikoerper) aus klinisch-epidemiologischer Sicht zu erwarten, ohne dass hierzu gesonderte gesundheitsoekonomische Berechnungen vorgelegt wurden. Andererseits konnte die Kosten-Effektivitaet eines generellen TSH-Screening ab dem 35. Lebensjahr in einer qualitativ hochwertigen gesundheitsoekonomischen Studie bereits belegt werden. Die Therapiestrategien bei gutartigen Schilddruesenerkrankungen (tertiaere Praevention) zielen auf eine Minimierung sekundaerer Krankheitsfolgen (Vorhofflimmern, Myokardinfarkt, Herztod) und iatrogener Nebenwirkungen. Beispiele fuer eine solche tertiaere Praevention sind die definitive Therapie (Radioiodtherapie) der Immunhyperthyreose M. Basedow bei unguenstigen initialen Praedikatoren fuer eine Rezidivhyperthyreose, die Radioiodtherapie der latenten Hyperthyreose sowie die Radioiodtherapie der grossvolumigen Struma bei aelteren oder

  17. Der Meteorologe : (aus dem Band "V". Tallinn 1998) / Elo Viiding ; aus dem Estnischen von Gisbert Jänicke

    Index Scriptorium Estoniae

    Viiding, Elo, 1974-

    2002-01-01

    Sisu : Die Möglichkeit des Meteorologen = Meteoroloogi võimalikkusest ; "Der Meteorologe kam 1990 in die Stadt..." = "Meteoroloog saabus linna aastal 1990..." ; "Was wäre dir "Arbeit" des Meteorologen..." = "Mis oleks meteoroloogi töö..." ; "Und ein Unglück für den Meteorologen ist es auch..." = "Ja Meteoroloogi õnnetus on veel see..." ; Angst vor dem Altwerden des Meteorologen = Hirm Meteoroloogi vanakssaamise ees ; Fest. Geschenk = Pidu. Kink ; "Wenn der Meteorologe eine Grösse sieht, ist er darüber..." = "Kui meteoroloog näeb suurust, on ta selle kohal..." ; Der Meteorologe wird im Saal erwartet = Meteoroloogi oodatakse saali ; "Das Abkommen mit der Meteorologenerwartung kündigen..." = "Katkestada leping meteoroloogiootusega..." ; "Die "Wege des Herrn" sind der Meteorologe..." = "Looja tee" on Meteoroloog..." ; Von dem Fremden, der im Saal den Meteorologen traf = Võõra lugu, kes Meteoroloogi saalis kohtas ; "Den Fremden hervorzuhusten, der von dem..." = "Köhida enesest välja võõras, kes tahtis teha..." ; Der Fremde beruhigt sich nicht = Võõras ei jää rahule

  18. A photogrammetric DEM of Greenland based on 1978-1987 aerial photos: validation and integration with laser altimetry and satellite-derived DEMs

    DEFF Research Database (Denmark)

    Korsgaard, Niels Jákup; Kjær, Kurt H.; Nuth, Christopher

    50 km to ICESat laser altimetry in order to evaluate the coherency. We complement the aero-photogrammetric DEM with modern laser altimetry and DEMs derived from stereoscopic satellite imagery (AST14DMO) to examine the mass variability of the Northeast Greenland Ice Stream (NEGIS). Our analysis...

  19. Wavelet based analysis of TanDEM-X and LiDAR DEMs across a tropical vegetation heterogeneity gradient driven by fire disturbance in Indonesia

    NARCIS (Netherlands)

    Grandi, De Elsa Carla; Mitchard, Edward; Hoekman, Dirk

    2016-01-01

    Three-dimensional information provided by TanDEM-X interferometric phase and airborne Light Detection and Ranging (LiDAR) Digital ElevationModels (DEMs) were used to detect differences in vegetation heterogeneity through a disturbance gradient in Indonesia. The range of vegetation types developed

  20. [Julia Rosche. Zwischen den Fronten. Die Rolle Estlands zwischen dem Hitler-Stalin-Pakt und dem Ende des Zweiten Weltkriegs im internationalen Kontext] / Olaf Mertelsmann

    Index Scriptorium Estoniae

    Mertelsmann, Olaf, 1969-

    2014-01-01

    Arvustus: Rosche, Julia. Zwischen den Fronten. Die Rolle Estlands zwischen dem Hitler-Stalin-Pakt und dem Ende des Zweiten Weltkriegs im internationalen Kontext. Diplomica Verlag. Hamburg 2012. Unter demselben Titel mit identischem Text auch: Grin Verlag. München 2013

  1. [Julia Rosche. Zwischen den Fronten. Die Rolle Estlands zwischen dem Hitler-Stalin-Pakt und dem Ende des Zweiten Weltkriegs im internationalen Kontext] / Olaf Mertelsmann

    Index Scriptorium Estoniae

    Mertelsmann, Olaf, 1969-

    2014-01-01

    Arvustus: Rosche, Julia. Zwischen den Fronten. Die Rolle Estlands zwischen dem Hitler-Stalin-Pakt und dem Ende des Zweiten Weltkriegs im internationalen Kontext. Diplomica Verlag. Hamburg 2012. Unter demselben Titel mit identischem Text auch: Grin Verlag. München 2013

  2. In need of combined topography and bathymetry DEM

    Science.gov (United States)

    Kisimoto, K.; Hilde, T.

    2003-04-01

    In many geoscience applications, digital elevation models (DEMs) are now more commonly used at different scales and greater resolution due to the great advancement in computer technology. Increasing the accuracy/resolution of the model and the coverage of the terrain (global model) has been the goal of users as mapping technology has improved and computers get faster and cheaper. The ETOPO5 (5 arc minutes spatial resolution land and seafloor model), initially developed in 1988 by Margo Edwards, then at Washington University, St. Louis, MO, has been the only global terrain model for a long time, and it is now being replaced by three new topographic and bathymetric DEMs, i.e.; the ETOPO2 (2 arc minutes spatial resolution land and seafloor model), the GTOPO30 land model with a spatial resolution of 30 arc seconds (c.a. 1km at equator) and the 'GEBCO 1-MINUTE GLOBAL BATHYMETRIC GRID' ocean floor model with a spatial resolution of 1 arc minute (c.a. 2 km at equator). These DEMs are products of projects through which compilation and reprocessing of existing and/or new datasets were made to meet user's new requirements. These ongoing efforts are valuable and support should be continued to refine and update these DEMs. On the other hand, a different approach to create a global bathymetric (seafloor) database exists. A method to estimate the seafloor topography from satellite altimetry combined with existing ships' conventional sounding data was devised and a beautiful global seafloor database created and made public by W.H. Smith and D.T. Sandwell in 1997. The big advantage of this database is the uniformity of coverage, i.e. there is no large area where depths are missing. It has a spatial resolution of 2 arc minute. Another important effort is found in making regional, not global, seafloor databases with much finer resolutions in many countries. The Japan Hydrographic Department has compiled and released a 500m-grid topography database around Japan, J-EGG500, in 1999

  3. Research on the method of extracting DEM based on GBInSAR

    Science.gov (United States)

    Yue, Jianping; Yue, Shun; Qiu, Zhiwei; Wang, Xueqin; Guo, Leping

    2016-05-01

    Precise topographical information has a very important role in geology, hydrology, natural resources survey and deformation monitoring. The extracting DEM technology based on synthetic aperture radar interferometry (InSAR) obtains the three-dimensional elevation of the target area through the phase information of the radar image data. The technology has large-scale, high-precision, all-weather features. By changing track in the location of the ground radar system up and down, it can form spatial baseline. Then we can achieve the DEM of the target area by acquiring image data from different angles. Three-dimensional laser scanning technology can quickly, efficiently and accurately obtain DEM of target area, which can verify the accuracy of DEM extracted by GBInSAR. But research on GBInSAR in extracting DEM of the target area is a little. For lack of theory and lower accuracy problems in extracting DEM based on GBInSAR now, this article conducted research and analysis on its principle deeply. The article extracted the DEM of the target area, combined with GBInSAR data. Then it compared the DEM obtained by GBInSAR with the DEM obtained by three-dimensional laser scan data and made statistical analysis and normal distribution test. The results showed the DEM obtained by GBInSAR was broadly consistent with the DEM obtained by three-dimensional laser scanning. And its accuracy is high. The difference of both DEM approximately obeys normal distribution. It indicated that extracting the DEM of target area based on GBInSAR is feasible and provided the foundation for the promotion and application of GBInSAR.

  4. A coupled DEM-CFD method for impulse wave modelling

    Science.gov (United States)

    Zhao, Tao; Utili, Stefano; Crosta, GiovanBattista

    2015-04-01

    Rockslides can be characterized by a rapid evolution, up to a possible transition into a rock avalanche, which can be associated with an almost instantaneous collapse and spreading. Different examples are available in the literature, but the Vajont rockslide is quite unique for its morphological and geological characteristics, as well as for the type of evolution and the availability of long term monitoring data. This study advocates the use of a DEM-CFD framework for the modelling of the generation of hydrodynamic waves due to the impact of a rapid moving rockslide or rock-debris avalanche. 3D DEM analyses in plane strain by a coupled DEM-CFD code were performed to simulate the rockslide from its onset to the impact with still water and the subsequent wave generation (Zhao et al., 2014). The physical response predicted is in broad agreement with the available observations. The numerical results are compared to those published in the literature and especially to Crosta et al. (2014). According to our results, the maximum computed run up amounts to ca. 120 m and 170 m for the eastern and western lobe cross sections, respectively. These values are reasonably similar to those recorded during the event (i.e. ca. 130 m and 190 m respectively). In these simulations, the slope mass is considered permeable, such that the toe region of the slope can move submerged in the reservoir and the impulse water wave can also flow back into the slope mass. However, the upscaling of the grains size in the DEM model leads to an unrealistically high hydraulic conductivity of the model, such that only a small amount of water is splashed onto the northern bank of the Vajont valley. The use of high fluid viscosity and coarse grain model has shown the possibility to model more realistically both the slope and wave motions. However, more detailed slope and fluid properties, and the need for computational efficiency should be considered in future research work. This aspect has also been

  5. Comparative DEMS study on the electrochemical oxidation of carbon blacks

    DEFF Research Database (Denmark)

    Ashton, Sean James; Arenz, Matthias

    2012-01-01

    heat-treated between 2100 and 3200 °C, such as those typically used as corrosion resistant carbon (CRC) supports for polymer electrolyte membrane fuel cell (PEMFC) catalysts. A methodology combining cyclic voltammetry (CV) and differential electrochemical mass spectrometry (DEMS) is used, which allows...... the characterisation and comparison of the complete electrochemical oxidation rates and behaviours of the various carbon blacks. It is observed that the behaviour of the carbon black towards electrochemical oxidation is highly dynamic, and dependent on the properties of the pristine carbon back, the degree...

  6. DEM simulation of heat transfer in granular materials

    Science.gov (United States)

    Gui, Nan; Xu, Wenkai; Ge, Liang

    2013-07-01

    This study investigates the heat conduction of low conductivity granular particles in a two-dimensional modeling of a rotary drum using discrete element method (DEM) method. The Shannon entropy and Lagrangian mean temperature difference are used for comparative study. The results obtained by these two methods are in accordance with each other. It shows the evolution of heat conduction in rotary drums can be divided into a dynamically dominated stage and a thermodynamically dominated stage. The former is determined mainly by particle mixing and the latter is by particle-particle contact duration. The mechanisms for these two stages are explained and the heat transfer characteristics in these two stages are explored.

  7. Influence of increased pressure on the biocenose of activated sludge; Einfluss von erhoehtem Betriebsdruck auf die Biozoenose des Belebtschlammes

    Energy Technology Data Exchange (ETDEWEB)

    Staab, K.F.; Wedekind, I.; Wedekind, P.

    1998-03-01

    In semi-technical experiments with pressure biology and membrane filtration for the separation of the liquid/solid system microscopic evaluations of the available biocenose were carried out. For these experiments over a period of one year, exclusively local effluent from the pre-settling tank of the teaching and research water treatment plant of the Institut fuer Siedlungswasserbau, Wasserguete- und Abfallwirtschaft of the Universitaet Stuttgart have been used. (orig.) [Deutsch] In halbtechnischen Versuchen mit Druckbiologie und Membranfiltration zur Trennung des Systems fluessig/fest wurden mikroskopische Beurteilungen der vorhandenen Biozoenose durchgefuehrt. Bei diesen Versuchen ueber einen Zeitraum von einem Jahr wurde ausschliesslich kommunales Abwasser aus dem Vorklaerbecken des Lehr- und Forschungsklaerwerks des Instituts fuer Siedlungswasserbau, Wasserguete- und Abfallwirtschaft der Universitaet Stuttgart verwendet. (orig.)

  8. Accuracy of Cartosat-1 DEM and its derived attribute at multiple scale representation

    Indian Academy of Sciences (India)

    Samadrita Mukherjee; Sandip Mukherjee; A Bhardwaj; Anirban Mukhopadhyay; R D Garg; S Hazra

    2015-04-01

    Digital Elevation Model (DEM) provides basic information about terrain relief and is used for morphological characterisation, hydrological modelling and infrastructural studies. This paper investigates the accuracy of DEM and its derived attributes in multiple scales. This study was carried out for a part of Shiwalik Himalaya using Cartosat-1 stereo pair data. DEM at various cell sizes were generated and information content was compared using mean elevation, variance and entropy statistics. Various post-spacing DEMs were validated to understand variation in vertical accuracy along different scales. The vertical accuracy (3.14–7.24 m) is affected in larger spacing DEM and elevation is underestimated. Slope of terrain also has similar impacts. The DEM and slope accuracy are also affected by the terrain roughness while assessing coarser grid size.

  9. The Importance of Precise Digital Elevation Models (DEM) in Modelling Floods

    Science.gov (United States)

    Demir, Gokben; Akyurek, Zuhal

    2016-04-01

    Digital elevation Models (DEM) are important inputs for topography for the accurate modelling of floodplain hydrodynamics. Floodplains have a key role as natural retarding pools which attenuate flood waves and suppress flood peaks. GPS, LIDAR and bathymetric surveys are well known surveying methods to acquire topographic data. It is not only time consuming and expensive to obtain topographic data through surveying but also sometimes impossible for remote areas. In this study it is aimed to present the importance of accurate modelling of topography for flood modelling. The flood modelling for Samsun-Terme in Blacksea region of Turkey is done. One of the DEM is obtained from the point observations retrieved from 1/5000 scaled orthophotos and 1/1000 scaled point elevation data from field surveys at x-sections. The river banks are corrected by using the orthophotos and elevation values. This DEM is named as scaled DEM. The other DEM is obtained from bathymetric surveys. 296 538 number of points and the left/right bank slopes were used to construct the DEM having 1 m spatial resolution and this DEM is named as base DEM. Two DEMs were compared by using 27 x-sections. The maximum difference at thalweg of the river bed is 2m and the minimum difference is 20 cm between two DEMs. The channel conveyance capacity in base DEM is larger than the one in scaled DEM and floodplain is modelled in detail in base DEM. MIKE21 with flexible grid is used in 2- dimensional shallow water flow modelling. The model by using two DEMs were calibrated for a flood event (July 9, 2012). The roughness is considered as the calibration parameter. From comparison of input hydrograph at the upstream of the river and output hydrograph at the downstream of the river, the attenuation is obtained as 91% and 84% for the base DEM and scaled DEM, respectively. The time lag in hydrographs does not show any difference for two DEMs and it is obtained as 3 hours. Maximum flood extents differ for the two DEMs

  10. Effects of lidar point density on bare earth extraction and DEM creation

    Science.gov (United States)

    Puetz, Angela M.; Olsen, R. Chris; Anderson, Brian

    2009-05-01

    Data density has a crucial impact on the accuracy of Digital Elevation Models (DEMs). In this study, DEMs were created from a high point-density LIDAR dataset using the bare earth extraction module in Quick Terrain Modeler. Lower point-density LIDAR collects were simulated by randomly selecting points from the original dataset at a series of decreasing percentages. The DEMs created from the lower resolution datasets are compared to the original DEM. Results show a decrease in DEM accuracy as the resolution of the LIDAR dataset is reduced. Some analysis is made of the types of errors encountered in the lower resolution DEMs. It is also noted that the percentage of points classified as bare earth decreases as the resolution of the LIDAR dataset is reduced.

  11. Mann und Frau in der OPD - der "kleine Unterschied"?:Untersuchung des Einflusses des Geschlechtes von Patienten/Patientinnen und Diagnostikern/Diagnostikerinnen auf die Befunde der Achsen "Beziehung", "Konflikt" und "Struktur" der Operationalisierten Psychodynamischen Diagnostik

    OpenAIRE

    Schmitz-Moormann, S. (Stefani)

    2005-01-01

    Untersuchung des Einflusses des Geschlechtes von Patienten und Diagnostikern auf die Befunde der Achsen II (dysfunktionelle Beziehungsmuster), III (überdauernde neurotische Konflikte) und IV (Ich-Struktur) der Operationalisierten Psychodynamischen Diagnostik (OPD). Befunde von 2739 männlichen und weiblichen Patienten einer psychosomatischen Universitäts-Poliklinik, erhoben von 7 männlichen und 7 weiblichen Diagnostikern, wurden untersucht. Auf der Beziehungsachse fanden sich Unterschiede, die...

  12. Einfluss der Kaliumdüngung auf das Wachstum und die Wassernutzungseffizienz von Ackerbohne (Vicia faba), Sommerweizen (Triticum aestivum) und Tomate (Solanum lycopersicum) unter Kontroll-, Trockenstress- bzw. Salinitätsbedingungen

    OpenAIRE

    Reeb, verh. Gerwers, Dominik

    2011-01-01

    Ziel dieser Arbeit war es, den speziellen Einfluss einer Kalium-(K)-Düngung auf das Pflanzenwachstum herauszustellen. Es wurde untersucht, ob der Wasserhaushalt der Pflanzen durch Kalium verbessert und inwiefern die Wassernutzungseffizienz (WUE) verändert wird. Dabei wurde auch nach speziellen Wirkungen von K auf die Verbesserung der WUE unter Trockenstress- und Salinitätsbedingungen geforscht. Die Verbesserung der WUE könnte auf eine Verringerung des Wasserverbrauches und /...

  13. A photogrammetric DEM of Greenland based on 1978-1987 aerial photos: validation and integration with laser altimetry and satellite-derived DEMs

    Science.gov (United States)

    Korsgaard, N. J.; Kjaer, K. H.; Nuth, C.; Khan, S. A.

    2014-12-01

    Here we present a DEM of Greenland covering all ice-free terrain and the margins of the GrIS and local glaciers and ice caps. The DEM is based on the 3534 photos used in the aero-triangulation which were recorded by the Danish Geodata Agency (then the Geodetic Institute) in survey campaigns spanning the period 1978-1987. The GrIS is covered tens of kilometers into the interior due to the large footprints of the photos (30 x 30 km) and control provided by the aero-triangulation. Thus, the data are ideal for providing information for analysis of ice marginal elevation change and also control for satellite-derived DEMs.The results of the validation, error assessments and predicted uncertainties are presented. We test the DEM using Airborne Topographic Mapper (IceBridge ATM) as reference data; evaluate the a posteriori covariance matrix from the aero-triangulation; and co-register DEM blocks of 50 x 50 km to ICESat laser altimetry in order to evaluate the coherency.We complement the aero-photogrammetric DEM with modern laser altimetry and DEMs derived from stereoscopic satellite imagery (AST14DMO) to examine the mass variability of the Northeast Greenland Ice Stream (NEGIS). Our analysis suggests that dynamically-induced mass loss started around 2003 and continued throughout 2014.

  14. Effect of aging in HDPE blended with DEM in decalin

    Energy Technology Data Exchange (ETDEWEB)

    Silva, P. [Centro de Fisica, IVIC, Carretera Panamericana Km. 11, Apartado 21827, Caracas 1020-A (Venezuela); Albano, C.; Karam, A.; Vargas, M.G. [Centro de Quimica, IVIC, (Venezuela); Perera, R. [Departamento de Mecanica, Universidad Simon Bolivar, Caracas (Venezuela)

    2006-07-01

    Electron paramagnetic resonance (EPR) was used to study the effect of aging on irradiated samples of high-density polyethylene (HDPE) blended with diethyl maleate (DEM) in different proportions. Initially, we synthesize the HDPE using bis-(cyclopentadienyl) zirconium dichloride and P-MAO. The functionalization of the synthesized HDPE was carried out in a 10% weight/vol of polyethylene in decalin solution using different percentages of diethyl maleate (5, 10, 15 and 30% in weight). The samples were irradiated at 5, 15 and 30 kGy. An exponential decay in the total free radicals concentration was observed in the pure HDPE sample at the 15 and 30 kGy irradiation doses, as it was expected. For the 15 and 30 kGy irradiation doses the HDPE blended with 15 and 30% of DEM in decalin shows an increase in the total free radical concentrations as the storage time is increased. This behavior has been interpreted in terms of trapped free radicals. (Author)

  15. An efficient method for DEM-based overland flow routing

    Science.gov (United States)

    Huang, Pin-Chun; Lee, Kwan Tun

    2013-05-01

    The digital elevation model (DEM) is frequently used to represent watershed topographic features based on a raster or a vector data format. It has been widely linked with flow routing equations for watershed runoff simulation. In this study, a recursive formulation was encoded into the conventional kinematic- and diffusion-wave routing algorithms to permit a larger time increment, despite the Courant-Friedrich-Lewy condition having been violated. To meet the requirement of recursive formulation, a novel routing sequence was developed to determine the cell-to-cell computational procedure for the DEM database. The routing sequence can be set either according to the grid elevation in descending order for the kinematic-wave routing or according to the water stage of the grid in descending order for the diffusion-wave routing. The recursive formulation for 1D runoff routing was first applied to a conceptual overland plane to demonstrate the precision of the formulation using an analytical solution for verification. The proposed novel routing sequence with the recursive formulation was then applied to two mountain watersheds for 2D runoff simulations. The results showed that the efficiency of the proposed method was significantly superior to that of the conventional algorithm, especially when applied to a steep watershed.

  16. GPU based contouring method on grid DEM data

    Science.gov (United States)

    Tan, Liheng; Wan, Gang; Li, Feng; Chen, Xiaohui; Du, Wenlong

    2017-08-01

    This paper presents a novel method to generate contour lines from grid DEM data based on the programmable GPU pipeline. The previous contouring approaches often use CPU to construct a finite element mesh from the raw DEM data, and then extract contour segments from the elements. They also need a tracing or sorting strategy to generate the final continuous contours. These approaches can be heavily CPU-costing and time-consuming. Meanwhile the generated contours would be unsmooth if the raw data is sparsely distributed. Unlike the CPU approaches, we employ the GPU's vertex shader to generate a triangular mesh with arbitrary user-defined density, in which the height of each vertex is calculated through a third-order Cardinal spline function. Then in the same frame, segments are extracted from the triangles by the geometry shader, and translated to the CPU-side with an internal order in the GPU's transform feedback stage. Finally we propose a ;Grid Sorting; algorithm to achieve the continuous contour lines by travelling the segments only once. Our method makes use of multiple stages of GPU pipeline for computation, which can generate smooth contour lines, and is significantly faster than the previous CPU approaches. The algorithm can be easily implemented with OpenGL 3.3 API or higher on consumer-level PCs.

  17. Simulation of triaxial response of granular materials by modified DEM

    Science.gov (United States)

    Wang, XiaoLiang; Li, JiaChun

    2014-12-01

    A modified discrete element method (DEM) with rolling effect taken into consideration is developed to examine macroscopic behavior of granular materials in this study. Dimensional analysis is firstly performed to establish the relationship between macroscopic mechanical behavior, mesoscale contact parameters at particle level and external loading rate. It is found that only four dimensionless parameters may govern the macroscopic mechanical behavior in bulk. The numerical triaxial apparatus was used to study their influence on the mechanical behavior of granular materials. The parametric study indicates that Poisson's ratio only varies with stiffness ratio, while Young's modulus is proportional to contact modulus and grows with stiffness ratio, both of which agree with the micromechanical model. The peak friction angle is dependent on both inter-particle friction angle and rolling resistance. The dilatancy angle relies on inter-particle friction angle if rolling stiffness coefficient is sufficiently large. Finally, we have recommended a calibration procedure for cohesionless soil, which was at once applied to the simulation of Chende sand using a series of triaxial compression tests. The responses of DEM model are shown in quantitative agreement with experiments. In addition, stress-strain response of triaxial extension was also obtained by numerical triaxial extension tests.

  18. DEM modeling of flexible structures against granular material avalanches

    Science.gov (United States)

    Lambert, Stéphane; Albaba, Adel; Nicot, François; Chareyre, Bruno

    2016-04-01

    This article presents the numerical modeling of flexible structures intended to contain avalanches of granular and coarse material (e.g. rock slide, a debris slide). The numerical model is based on a discrete element method (YADE-Dem). The DEM modeling of both the flowing granular material and the flexible structure are detailed before presenting some results. The flowing material consists of a dry polydisperse granular material accounting for the non-sphericity of real materials. The flexible structure consists in a metallic net hanged on main cables, connected to the ground via anchors, on both sides of the channel, including dissipators. All these components were modeled as flexible beams or wires, with mechanical parameters defined from literature data. The simulation results are presented with the aim of investigating the variability of the structure response depending on different parameters related to the structure (inclination of the fence, with/without brakes, mesh size opening), but also to the channel (inclination). Results are then compared with existing recommendations in similar fields.

  19. Environmental effects on fatigue of steels for structural parts in water-steam-circuits of light water reactors. Considerations concerning the question of transferability of results from laboratory tests to real operating conditions; Der Einfluss des Mediums auf Ermuedungsvorgaenge in Staehlen fuer Strukturbauteile in Wasser-Dampf-Kreislaeufen von Leichtwasserreaktoren. Ueberlegungen zur Frage der Uebertragbarkeit von Ergebnissen aus Laborversuchen auf den realen Anlagenbetrieb

    Energy Technology Data Exchange (ETDEWEB)

    Roth, Armin [AREVA NP GmbH, Erlangen (Germany)

    2008-07-01

    .B. von Staehlen, beeinflussen kann. Schon vor einigen Jahrzehnten wurde experimentell nachgewiesen, dass z.B. Hochtemperaturwasser in Laborversuchen zur Untersuchung des Ermuedungsverhaltens von Staehlen zu deutlichen Effekten fuehrt. Dabei wird je nach Versuchsfuehrung entweder die Zeit bis zur Initiierung von Anrissen verkuerzt oder die Wachstumsgeschwindigkeit vorhandener Risse erhoeht. Dieser zu erwartende Einfluss des Mediums auf den Ermuedungsprozess wurde in den Anfaengen der Regulierung von Konstruktion und Auslegung von Bauteilen und Komponenten fuer Kernkraftwerke in den relevanten Regelwerken (z.B. ASME Boiler and Pressure Vessel Code, Section III) weltweit nicht explizit beruecksichtigt. Pauschal beruecksichtigt werden Umgebungseffekte dagegen in den entsprechenden da/dN-Risswachstumskurven des ASME Code, Section XI zur Bewertung des betrieblichen Verhaltens von Oberflaechenfehlern. Historisch betrachtet erfolgte in den Regelwerken die Festlegung der Vorgehensweise zur Komponentenauslegung allerdings lange vor dem gezielten experimentellen Nachweis der Umgebungseffekte auf Rissinitiierung und Risswachstum durch Ermuedung von Staehlen in Hochtemperaturwasser. Trotz dieser Erkenntnis ist es weltweit nicht zu generischen, systematischen Schaeden in Medium fuehrenden Systemen von Leichtwasserreaktoren (LWR) durch Korrosionsermuedung infolge von Fehlauslegung gekommen. Vereinzelt aufgetretene Schaeden mit deutlichen Merkmalen umgebungsbeeinflusster Ermuedungsvorgaenge konnten immer eindeutig auf das Vorkommen von unerwarteten, nicht im spezifizierten Belastungskollektiv enthaltenen Betriebstransienten zurueckgefuehrt werden. Zu diesen Ursachen zaehlen z.B. das Auftreten von thermischer Schichtung oder lokale, stroemungsinduzierte Vibrationen. In diesem Beitrag werden Ueberlegungen vorgestellt, welche die zu beobachtende Diskrepanz zwischen der diesbezueglich weltweit ueberwiegend positiven Betriebserfahrung und den Ergebnissen aus Laborversuchen mit dem

  20. Review of Digital Elevation Model (DEM) Based Research on China Loess Plateau

    Institute of Scientific and Technical Information of China (English)

    Tang Guo'an; Ge Shanshan; Li Fayuan; Zhou Jieyu

    2005-01-01

    The Loess Plateau is one of the hot research areas for its specific geographical features. In resent years, with the establishment of national multi-scale DEMs and the perfection of DEM based digital terrain analysis methods, new thoughts and methodologies have been constructed for the Loess Plateau research. This paper introduces the characteristics of DEM data, analyses the development stages of DEM applied in the Loess Plateau research, and discusses its further possible research direction. More discussions are focused on slope spectrum and its concept, as well as the significance in the Loess Plateau research.

  1. DEM Resolution Impact on the Estimation of the Physical Characteristics of Watersheds by Using SWAT

    Directory of Open Access Journals (Sweden)

    Waranyu Buakhao

    2016-01-01

    Full Text Available A digital elevation model (DEM is an important spatial input for automatic extraction of topographic parameters for the soil and water assessment tool (SWAT. The objective of this study was to investigate the impact of DEM resolution (from 5 to 90 m on the delineation process of a SWAT model with two types of watershed characteristics (flat area and mountain area and three sizes of watershed area (about 20,000, 200,000, and 1,500,000 hectares. The results showed that the total lengths of the streamline, main channel slope, watershed area, and area slope were significantly different when using the DEM datasets to delineate. Delineation using the SRTM DEM (90 m, ASTER DEM (30 m, and LDD DEM (5 m for all watershed characteristics showed that the watershed sizes and shapes obtained were only slightly different, whereas the area slopes obtained were significantly different. The total lengths of the generated streams increased when the resolution of the DEM used was higher. The stream slopes obtained using the small area sizes were insignificant, whereas the slopes obtained using the large area sizes were significantly different. This suggests that water resource model users should use the ASTER DEM as opposed to a finer resolution DEM for model input to save time for the model calibration and validation.

  2. Shuttle radar DEM hydrological correction for erosion modelling in small catchments

    Science.gov (United States)

    Jarihani, Ben; Sidle, Roy; Bartley, Rebecca

    2016-04-01

    Digital Elevation Models (DEMs) that accurately replicate both landscape form and processes are critical to support modelling of environmental processes. Catchment and hillslope scale runoff and sediment processes (i.e., patterns of overland flow, infiltration, subsurface stormflow and erosion) are all topographically mediated. In remote and data-scarce regions, high resolution DEMs (LiDAR) are often not available, and moderate to course resolution digital elevation models (e.g., SRTM) have difficulty replicating detailed hydrological patterns, especially in relatively flat landscapes. Several surface reconditioning algorithms (e.g., Smoothing) and "Stream burning" techniques (e.g., Agree or ANUDEM), in conjunction with representation of the known stream networks, have been used to improve DEM performance in replicating known hydrology. Detailed stream network data are not available at regional and national scales, but can be derived at local scales from remotely-sensed data. This research explores the implication of high resolution stream network data derived from Google Earth images for DEM hydrological correction, instead of using course resolution stream networks derived from topographic maps. The accuracy of implemented method in producing hydrological-efficient DEMs were assessed by comparing the hydrological parameters derived from modified DEMs and limited high-resolution airborne LiDAR DEMs. The degree of modification is dominated by the method used and availability of the stream network data. Although stream burning techniques improve DEMs hydrologically, these techniques alter DEM characteristics that may affect catchment boundaries, stream position and length, as well as secondary terrain derivatives (e.g., slope, aspect). Modification of a DEM to better reflect known hydrology can be useful, however, knowledge of the magnitude and spatial pattern of the changes are required before using a DEM for subsequent analyses.

  3. Uncertainty of soil erosion modelling using open source high resolution and aggregated DEMs

    Directory of Open Access Journals (Sweden)

    Arun Mondal

    2017-05-01

    Full Text Available Digital Elevation Model (DEM is one of the important parameters for soil erosion assessment. Notable uncertainties are observed in this study while using three high resolution open source DEMs. The Revised Universal Soil Loss Equation (RUSLE model has been applied to analysis the assessment of soil erosion uncertainty using open source DEMs (SRTM, ASTER and CARTOSAT and their increasing grid space (pixel size from the actual. The study area is a part of the Narmada river basin in Madhya Pradesh state, which is located in the central part of India and the area covered 20,558 km2. The actual resolution of DEMs is 30 m and their increasing grid spaces are taken as 90, 150, 210, 270 and 330 m for this study. Vertical accuracy of DEMs has been assessed using actual heights of the sample points that have been taken considering planimetric survey based map (toposheet. Elevations of DEMs are converted to the same vertical datum from WGS 84 to MSL (Mean Sea Level, before the accuracy assessment and modelling. Results indicate that the accuracy of the SRTM DEM with the RMSE of 13.31, 14.51, and 18.19 m in 30, 150 and 330 m resolution respectively, is better than the ASTER and the CARTOSAT DEMs. When the grid space of the DEMs increases, the accuracy of the elevation and calculated soil erosion decreases. This study presents a potential uncertainty introduced by open source high resolution DEMs in the accuracy of the soil erosion assessment models. The research provides an analysis of errors in selecting DEMs using the original and increased grid space for soil erosion modelling.

  4. Investigations on cathodic control of chloride-induced reinforcement corrosion; Zum Einfluss der kathodischen Reaktion auf die chloridinduzierte Bewehrungskorrosion

    Energy Technology Data Exchange (ETDEWEB)

    Raupach, M. [RWTH Aachen (Germany). Inst. fuer Bauforschung; Gulikers, J. [Ministerium fuer Verkehr, Wasserwirtschaft und oeffentliche Arbeiten, Bauamt, Utrecht (Netherlands)

    2001-10-01

    Regarding the mechanisms of reinforcement corrosion there are still contradictions with respect to the controlling/rate-determining factors of the corrosion process. It is often discussed, that the electrolytic resistance of the concrete is the controlling factor and that the corrosion rates can subsequently be calculated from concrete resistivity. However, extensive research carried out by the authors has clearly demonstrated, that instead of concrete resistivity the resistance to cathodic polarisation normally is the controlling factor in the case of chloride-induced macrocell-corrosion. Generally, cathodic control can be related to restricted oxygen diffusion or activation control. In the present paper, these relationships are discussed in detail by results of numerous tests on the cathodic polarisation behaviour of passive reinforcement. For simple defined geometrical conditions simulating practical cases it is shown by a numerical analysis that the resistance to activation is normally the controlling factor for the corrosion rate and that oxygen diffusion has only to be taken into account, when the concrete is permanently water saturated or extremely dense. To verify, whether it is correct to estimate corrosion rates from resistivity data, tests should be carried out to check the influencing parameters on concrete resistivity and cathodic activation of passive steel surface areas. (orig.) [German] In Bezug auf die Mechanismen der Korrosion der Bewehrung gibt es immer noch Widersprueche im Hinblick auf die steuernden, geschwindigkeitsbestimmenden Faktoren des Korrosionsprozesses. Es wird oft diskutiert, dass der elektrolytische Widerstand des Betons der steuernde Faktor ist, und dass die Korrosionsgeschwindigkeiten folglich aus dem elektrolytischen Widerstand des Betons berechnet werden koennen. Umfangreiche, von den Autoren ausgefuehrte Studien haben jedoch deutlich gezeigt, dass anstelle des elektrolytischen Widerstands des Betons der kathodische

  5. 无人机遥感技术制作 DEM 新方法%The New Method of UAV Remote Sensing Producing DEM

    Institute of Scientific and Technical Information of China (English)

    柏飞

    2015-01-01

    UAV remote sensing technology to rapidly produce surface model DSM ,due to the existence of the survey area was surface features ,surface model can not substitute DEM ,this paper using a laser point cloud processing software terrasolid software ,through the elevation point cloud classification algorithm for data classification ,by people mutual fast machine to extract ground points make DEM.%无人机遥感技术能够快速制作地表模型DSM ,由于测区地物的存在,地表模型不能替代DEM ,本文提出利用激光点云处理软件 Terrasolid软件,通过高程分类算法对点云数据进行分类,通过人机互助快速提取出地面点制作DEM

  6. Digital Elevation Model (DEM), GRID derived from USGS .dem, Published in 2007, 1:600 (1in=50ft) scale, Shawnee County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Digital Elevation Model (DEM) dataset, published at 1:600 (1in=50ft) scale, was produced all or in part from LIDAR information as of 2007. It is described as...

  7. Digital Elevation Model (DEM), 5 Meter Auto-correlated DEM, Published in 2006, 1:24000 (1in=2000ft) scale, State of Utah Automated Geographic Reference Center.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Digital Elevation Model (DEM) dataset, published at 1:24000 (1in=2000ft) scale, was produced all or in part from Other information as of 2006. It is described...

  8. Digital Elevation Model (DEM), 2 Meter LIDAR Bare Earth DEM, Published in 2006, 1:12000 (1in=1000ft) scale, State of Utah Automated Geographic Reference Center.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Digital Elevation Model (DEM) dataset, published at 1:12000 (1in=1000ft) scale, was produced all or in part from LIDAR information as of 2006. It is described...

  9. Digital Elevation Model (DEM), Allegany County DEM 10 ft pixel, Published in 2005, 1:1200 (1in=100ft) scale, Allegany County Government.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Digital Elevation Model (DEM) dataset, published at 1:1200 (1in=100ft) scale, was produced all or in part from LIDAR information as of 2005. It is described as...

  10. Evaluation of ASTER GDEM2 in Comparison with GDEM1, SRTM DEM and Topographic-Map-Derived DEM Using Inundation Area Analysis and RTK-dGPS Data

    Directory of Open Access Journals (Sweden)

    Beni Raharjo

    2012-08-01

    Full Text Available This study evaluates the quality of the Advanced Spaceborne Thermal Emission Radiometer-Global Digital Elevation Model version 2 (ASTER GDEM2 in comparison with the previous version (GDEM1 as well as the Shuttle Radar Topographic Mission (SRTM DEM and topographic-map-derived DEM (Topo-DEM using inundation area analysis for the projected location of the Karian dam, Indonesia. In addition, the vertical accuracy of each DEM is evaluated using the Real-Time Kinematic differential Global Positioning Systems (RTK-dGPS data obtained from an intensive geodetic survey. The results of the inundation area analysis show that GDEM2 produced a higher maximum contour level (MCL (64 m than did GDEM1 (55 m, and thus, GDME2 has a better quality. In addition, the GDEM2-derived MCL is similar to those produced by SRTM DEM (69 m and Topo-DEM (62 m. The improvement in the contour level in GDEM2 is believed to be related to the successful removal of voids (artifacts and anomalies present in GDEM1. However, our RTK-dGPS results show that the vertical accuracy of GDEM2 is much lower than that of GDEM1 and the other DEMs, which is contradictory to the accuracy stated in the GDEM2 validation document. The vertical profiles of all DEMs show that GDEM2 contains a comparatively large number of undulation effects, thereby resulting in higher root mean square error (RMSE values. These undulation effects may have been introduced during the GDEM2 validation process. Although the results of this study may be site-specific, it is important that they be considered for the improvement of the next GDEM version.

  11. DEM simulations of die filling during pharmaceutical tabletting

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The flow behaviour of powders from a stationary shoe into a moving die, which mimics the die filling process in a rotary tablet press, was analysed using a discrete element method (DEM), in which 2D irregular shaped particles were considered. The influence of the particle shape,size and size distribution, the number of particles used in the simulation, the initial height of powder bed in the shoe, and the filling speed on the average mass flow rate and the critical filling speed (the highest speed at which the die can be completely filled) were explored. It has been found that a maximum flow rate is obtained at the critical filling speed for all systems investigated and poly-disperse systems have higher mass flow rates and higher critical filling speeds than mono-disperse systems. In addition, the powder with particles which can tessellate generally has a lower filling rate and a lower critical filling speed.

  12. Vibration induced flow in hoppers: DEM 2D polygon model

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    A two-dimensional discrete element model (DEM) simulation of cohesive polygonal particles has been developed to assess the benefit of point source vibration to induce flow in wedge-shaped hoppers. The particle-particle interaction model used is based on a multi-contact principle.The first part of the study investigated particle discharge under gravity without vibration to determine the critical orifice size (Be) to just sustain flow as a function of particle shape. It is shown that polygonal-shaped particles need a larger orifice than circular particles. It is also shown that Be decreases as the number of particle vertices increases. Addition of circular particles promotes flow of polygons in a linear manner.The second part of the study showed that vibration could enhance flow, effectively reducing Be. The model demonstrated the importance of vibrator location (height), consistent with previous continuum model results, and vibration amplitude in enhancing flow.

  13. Modeling slow deformation of polygonal particles using DEM

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    We introduce two improvements in the numerical scheme to simulate collision and slow shearing of irregular particles. First, we propose an alternative approach based on simple relations to compute the frictional contact forces. The approach improves efficiency and accuracy of the Discrete Element Method (DEM) when modeling the dynamics of the granular packing. We determine the proper upper limit for the integration step in the standard numerical scheme using a wide range of material parameters. To this end, we study the kinetic energy decay in a stress controlled test between two particles. Second, we show that the usual way of defining the contact plane between two polygonal particles is, in general, not unique which leads to discontinuities in the direction of the contact plane while particles move. To solve this drawback, we introduce an accurate definition for the contact plane based on the shape of the overlap area between touching particles, which evolves continuously in time.

  14. Influence of dem in Watershed Management as Flood Zonation Mapping

    Science.gov (United States)

    Alrajhi, Muhamad; Khan, Mudasir; Afroz Khan, Mohammad; Alobeid, Abdalla

    2016-06-01

    Despite of valuable efforts from working groups and research organizations towards flood hazard reduction through its program, still minimal diminution from these hazards has been realized. This is mainly due to the fact that with rapid increase in population and urbanization coupled with climate change, flood hazards are becoming increasingly catastrophic. Therefore there is a need to understand and access flood hazards and develop means to deal with it through proper preparations, and preventive measures. To achieve this aim, Geographical Information System (GIS), geospatial and hydrological models were used as tools to tackle with influence of flash floods in the Kingdom of Saudi Arabia due to existence of large valleys (Wadis) which is a matter of great concern. In this research paper, Digital Elevation Models (DEMs) of different resolution (30m, 20m,10m and 5m) have been used, which have proven to be valuable tool for the topographic parameterization of hydrological models which are the basis for any flood modelling process. The DEM was used as input for performing spatial analysis and obtaining derivative products and delineate watershed characteristics of the study area using ArcGIS desktop and its Arc Hydro extension tools to check comparability of different elevation models for flood Zonation mapping. The derived drainage patterns have been overlaid over aerial imagery of study area, to check influence of greater amount of precipitation which can turn into massive destructions. The flow accumulation maps derived provide zones of highest accumulation and possible flow directions. This approach provide simplified means of predicting extent of inundation during flood events for emergency action especially for large areas because of large coverage area of the remotely sensed data.

  15. Evaluating Error of LIDAR Derived dem Interpolation for Vegetation Area

    Science.gov (United States)

    Ismail, Z.; Khanan, M. F. Abdul; Omar, F. Z.; Rahman, M. Z. Abdul; Mohd Salleh, M. R.

    2016-09-01

    Light Detection and Ranging or LiDAR data is a data source for deriving digital terrain model while Digital Elevation Model or DEM is usable within Geographical Information System or GIS. The aim of this study is to evaluate the accuracy of LiDAR derived DEM generated based on different interpolation methods and slope classes. Initially, the study area is divided into three slope classes: (a) slope class one (0° - 5°), (b) slope class two (6° - 10°) and (c) slope class three (11° - 15°). Secondly, each slope class is tested using three distinctive interpolation methods: (a) Kriging, (b) Inverse Distance Weighting (IDW) and (c) Spline. Next, accuracy assessment is done based on field survey tachymetry data. The finding reveals that the overall Root Mean Square Error or RMSE for Kriging provided the lowest value of 0.727 m for both 0.5 m and 1 m spatial resolutions of oil palm area, followed by Spline with values of 0.734 m for 0.5 m spatial resolution and 0.747 m for spatial resolution of 1 m. Concurrently, IDW provided the highest RMSE value of 0.784 m for both spatial resolutions of 0.5 and 1 m. For rubber area, Spline provided the lowest RMSE value of 0.746 m for 0.5 m spatial resolution and 0.760 m for 1 m spatial resolution. The highest value of RMSE for rubber area is IDW with the value of 1.061 m for both spatial resolutions. Finally, Kriging gave the RMSE value of 0.790m for both spatial resolutions.

  16. Two Preliminary SRTM DEMs Within the Amazon Basin

    Science.gov (United States)

    Alsdorf, D.; Hess, L.; Melack, J.; Dunne, T.; Mertes, L.; Ballantine, A.; Biggs, T.; Holmes, K.; Sheng, Y.; Hendricks, G.

    2002-12-01

    Digital topography provides important measures, such as hillslope lengths and flow path networks, for understanding hydrologic and geomorphic processes (e.g., runoff response to land use change and floodplain inundation volume). Two preliminary Shuttle Radar Topography Mission digital elevation models of Manaus (1S to 5S and 59W to 63W) and Rondonia (9S to 12S and 61W to 64W) were received from NASA JPL in August 2002. The "PI Processor" produced these initial DEM segments and we are using them to assess the initial accuracy of the interferometrically derived heights and for hydrologic research. The preliminary SRTM derived absolute elevations across the Amazon floodplain in the Cabaliana region generally range from 5 to 15 m with reported errors of 1 to 3 m. This region also includes some preliminary elevations that are erroneously negative. However, topographic contours on 1:100,000 scale quadrangles of 1978 to 1980 vintage indicate elevations of 20 to 30 m. Because double-bounce travel paths are possible over the sparsely vegetated and very-flat 2400 sq-km water surface of the Balbina reservoir near Manaus, it serves to identify the relative accuracy of the SRTM heights. Here, cell-to-cell height changes are generally 0 to 1 m and changes across a ~100 km transect rarely exceed 3 m. Reported errors throughout the transect range from 1 to 2 m with some errors up to 5 m. Deforestation in Rondonia is remarkably clear in the C-band DEM where elevations are recorded from the canopy rather than bare earth. Here, elevation changes are ~30 m (with reported 1 to 2 m errors) across clear-cut areas. Field derived canopy heights are in agreement with this change. Presently, we are deriving stream networks in the Amazon floodplain for comparison with our previous network extraction from JERS-1 SAR mosaics and for hydrologic modeling.

  17. EVALUATING ERROR OF LIDAR DERIVED DEM INTERPOLATION FOR VEGETATION AREA

    Directory of Open Access Journals (Sweden)

    Z. Ismail

    2016-09-01

    Full Text Available Light Detection and Ranging or LiDAR data is a data source for deriving digital terrain model while Digital Elevation Model or DEM is usable within Geographical Information System or GIS. The aim of this study is to evaluate the accuracy of LiDAR derived DEM generated based on different interpolation methods and slope classes. Initially, the study area is divided into three slope classes: (a slope class one (0° – 5°, (b slope class two (6° – 10° and (c slope class three (11° – 15°. Secondly, each slope class is tested using three distinctive interpolation methods: (a Kriging, (b Inverse Distance Weighting (IDW and (c Spline. Next, accuracy assessment is done based on field survey tachymetry data. The finding reveals that the overall Root Mean Square Error or RMSE for Kriging provided the lowest value of 0.727 m for both 0.5 m and 1 m spatial resolutions of oil palm area, followed by Spline with values of 0.734 m for 0.5 m spatial resolution and 0.747 m for spatial resolution of 1 m. Concurrently, IDW provided the highest RMSE value of 0.784 m for both spatial resolutions of 0.5 and 1 m. For rubber area, Spline provided the lowest RMSE value of 0.746 m for 0.5 m spatial resolution and 0.760 m for 1 m spatial resolution. The highest value of RMSE for rubber area is IDW with the value of 1.061 m for both spatial resolutions. Finally, Kriging gave the RMSE value of 0.790m for both spatial resolutions.

  18. Political economy of renewable energy policy in Germany. A consideration of the policy making process in the electricity market under the influence of interest groups; Politische Oekonomie der Erneuerbare-Energien-Politik in Deutschland. Eine Betrachtung des Politikbildungsprozesses auf dem Strommarkt unter dem Einfluss von Interessengruppen

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, Tom

    2015-07-01

    In the research, it is argued that the targeted promotion of renewables leads to a change in the technological path dependency on the electricity market or led. The historically market depending portfolio of products in the conventional power industry will be replaced by an increasingly strong dependence on the product portfolio of Renewable Energy Sector according to this argumentation. The present work is devoted to the political explanation of the change and transition process in the electricity market. The process of policy formation in this market (especially support policies for renewable energies) will be discussed. It is examined from a public choice perspective, which political actors and instances in the past were responsible for the development and maintenance of individual policy elements. In particular, in this analysis the different private sector stakeholders in the electricity market move to center of attention. [German] In der Forschung wird argumentiert, dass die gezielte Foerderung der Erneuerbaren zu einer Veraenderung der technologischen Pfadabhaengigkeit am Strommarkt fuehrt bzw. gefuehrt hat. Die historisch bedingte Marktabhaengigkeit vom Angebotsportfolio der konventionellen Stromindustrie wird im Rahmen dieser Argumentation durch eine zunehmend starke Abhaengigkeit vom Angebotsportfolio des Erneuerbare-Eenergie-Bereichs ersetzt. Die vorliegende Arbeit widmet sich der politischen Erklaerung des Veraenderungs- bzw. Uebergangsprozesses am Strommarkt. Der Prozess der Politikbildung auf diesem Markt (v.a. der Foerderpolitik fuer erneuerbare Energien) wird diskutiert. Es wird aus einer Public-Choice-Perspektive untersucht, welche politischen Akteure und Instanzen in der Vergangenheit fuer die Entstehung und Aufrechterhaltung einzelner Politikelemente verantwortlich waren. Insbesondere ruecken bei dieser Betrachtung die unterschiedlichen privatwirtschaftlichen Interessengruppen am Strommarkt ins Zentrum der Aufmerksamkeit.

  19. Zur Internationalität der Pädagogischen Psychologie aus dem deutschsprachigen Bereich

    OpenAIRE

    Krampen, Günter; Schui, Gabriel

    2007-01-01

    Vor dem Hintergrund der Internationalisierungsdebatte der Psychologie in den deutschsprachigen Ländern wird der Internationalisierungsgrad der Pädagogischen Psychologie im Vergleich zur gesamten psychologischen Forschung aus dem deutschsprachigen Bereich unter zwei Perspektiven bibliometrisch untersucht: Zum ersten geht es inhaltlich um die Entwicklung der englischsprachigen Anteile der in PSYNDEX unter der Klassifikation "Pädagogische Psychologie" dokumentierten Literatur, zum zweiten um Ana...

  20. Evaluating the influence of spatial resolutions of DEM on watershed runoff and sediment yield using SWAT

    Indian Academy of Sciences (India)

    A Sivasena Reddy; M Janga Reddy

    2015-10-01

    Digital elevation model (DEM) of a watershed forms key basis for hydrologic modelling and its resolution plays a key role in accurate prediction of various hydrological processes. This study appraises the effect of different DEMs with varied spatial resolutions (namely TOPO 20 m, CARTO 30 m, ASTER 30 m, SRTM 90 m, GEO-AUS 500 m and USGS 1000 m) on hydrological response of watershed using Soil and Water Assessment Tool (SWAT) and applied for a case study of Kaddam watershed in India for estimating runoff and sediment yield. From the results of case study, it was observed that reach lengths, reach slopes, minimum and maximum elevations, sub-watershed areas, land use mapping areas within the sub-watershed and number of HRUs varied substantially due to DEM resolutions, and consequently resulted in a considerable variability in estimated daily runoff and sediment yields. It was also observed that, daily runoff values have increased (decreased) on low (high) rainy days respectively with coarser resolution of DEM. The daily sediment yield values from each sub-watershed decreased with coarser resolution of the DEM. The study found that the performance of SWAT model prediction was not influenced much for finer resolution DEMs up to 90 m for estimation of runoff, but it certainly influenced the estimation of sediment yields. The DEMs of TOPO 20 m and CARTO 30 m provided better estimates of sub-watershed areas, runoff and sediment yield values over other DEMs.

  1. Gedichte / [Konnula, Margus] Contra ; aus dem Estnischen von Gisbert Jänicke

    Index Scriptorium Estoniae

    Contra, pseud., 1974-

    2002-01-01

    Sisu : Die Nacht auf dem Busbahnhof = Öö bussijaamas ; Ich bin schwarz und schmutzig = Olen must ja räpane ; "wir sind da auf dem bild..." = "oleme siin pildi peal..." ; Lebensgrundlage = Elu alus ; Der Volksvertreter = Rahvaasemik ; Das Messer hinterm Rücken in der Hand = Selja taga nuga käes ; Wo = Kus ; Gute Nachbarn = Head naabrid

  2. Dementia-free life expectancy (demFLE) in the Netherlands

    NARCIS (Netherlands)

    Perenboom, R.J.M.; Boshuizen, H.C.; Breteler, M.M.B.; Alewijn, O.; Water, H.P.A. van de

    1996-01-01

    To gain an insight into the burden of dementia in an aging society, life expectancy with dementia and its counterpart dementia-free life expectancy (DemFLE) in The Netherlands are presented. Sullivan's method was used to calculate DemFLE. For elderly living either independently or in homes for the e

  3. Flow Dynamics of green sand in the DISAMATIC moulding process using Discrete element method (DEM)

    DEFF Research Database (Denmark)

    Hovad, Emil; Larsen, P.; Walther, Jens Honore

    2015-01-01

    The DISAMATIC casting process production of sand moulds is simulated with DEM (discrete element method). The main purpose is to simulate the dynamics of the flow of green sand, during the production of the sand mould with DEM. The sand shot is simulated, which is the first stage of the DISAMATIC...

  4. Characterisation of different vegetable motor fuels with regard to their suitability as diesel substitutes and with special consideration to their chemical and physical properties; Charakterisierung verschiedener Pflanzenoelkraftstoffe hinsichtlich ihrer Eignung als Dieselkraftstoffsubstitute unter besonderer Beruecksichtigung ihrer chemischen und physikalischen Eigenschaften

    Energy Technology Data Exchange (ETDEWEB)

    Klee, P.H.

    1999-10-01

    The author presents a characterisation of vegetable motor fuels on the basis of their chemical and physical properties. Apart from commercial diesel fuel, he investigated a rapeseed oil mixed fuel and four vegetable oil methyl esters. Exhaust emissions of aldehydes, ketones and PAH, both with and without legal limit values, were measured and compared with emissions using an oxidation catalytic converter. Different types of modifications were made in the fuel injection system of the engine in order to reduce nitric oxide emissions. The investigations show that vegetable fuels have an advantage in terms of emissions. Vegetable fuel structure and emission characteristics were shown to correlate. [Deutsch] In der vorliegenden Arbeit erfolgt eine umfassende Charakterisierung der motorischen Verwendung von verschiedenen Pflanzenkraftstoffen auf der Basis ihrer chemischen und physikalischen Eigenschaften. Neben handelsueblichem Dieselkraftstoff werden ein Rapsoelmischkraftstoff und vier Pflanzenoelmethylester untersucht. Es werden sowohl die gesetzlich limitierten, als auch die gesetzlich nicht limitierten Abgasemissionen an Aldehyden, Ketonen und polyzyklischen aromatischen Kohlenwasserstoffen untersucht. Die Rohemissionen werden mit den Emissionen unter Verwendung eines Oxidationskatalysators verglichen. Zur Absenkung der Stickoxidemissionen unter Verwendung von Pflanzenkraftstoffen werden verschiedene Modifikationen am Einspritzsystem des Motors vorgenommen. Die durchgefuehrten Untersuchungen zeigen weitreichende Emissionsvorteile von Pflanzenkraftstoffen auf. Der systematische Zusammenhang zwischen Pflanzenkraftstoffstruktur und Emissionsverhalten wird nachgewiesen. (orig.)

  5. ICESAT VALIDATION OF TANDEM-X I-DEMS OVER THE UK

    Directory of Open Access Journals (Sweden)

    L. Feng

    2016-06-01

    Full Text Available From the latest TanDEM-X mission (bistatic X-Band interferometric SAR, globally consistent Digital Elevation Model (DEM will be available from 2017, but their accuracy has not yet been fully characterised. This paper presents the methods and implementation of statistical procedures for the validation of the vertical accuracy of TanDEM-X iDEMs at grid-spacing of approximately 12.5 m, 30 m and 90 m based on processed ICESat data over the UK in order to assess their potential extrapolation across the globe. The accuracy of the TanDEM-X iDEM in UK was obtained as follows: against ICESat GLA14 elevation data, TanDEM-X iDEM has −0.028±3.654 m over England and Wales and 0.316 ± 5.286 m over Scotland for 12 m, −0.073 ± 6.575 m for 30 m, and 0.0225 ± 9.251 m at 90 m. Moreover, 90 % of all results at the three resolutions of TanDEM-X iDEM data (with a linear error at 90 % confidence level are below 16.2 m. These validation results also indicate that derivative topographic parameters (slope, aspect and relief have a strong effect on the vertical accuracy of the TanDEM-X iDEMs. In high-relief and large slope terrain, large errors and data voids are frequent, and their location is strongly influenced by topography, whilst in the low- to medium-relief and low slope sites, errors are smaller. ICESat derived elevations are heavily influenced by surface slope within the 70 m footprint as well as there being slope dependent errors in the TanDEM-X iDEMs.

  6. Icesat Validation of Tandem-X I-Dems Over the UK

    Science.gov (United States)

    Feng, L.; Muller, J.-P.

    2016-06-01

    From the latest TanDEM-X mission (bistatic X-Band interferometric SAR), globally consistent Digital Elevation Model (DEM) will be available from 2017, but their accuracy has not yet been fully characterised. This paper presents the methods and implementation of statistical procedures for the validation of the vertical accuracy of TanDEM-X iDEMs at grid-spacing of approximately 12.5 m, 30 m and 90 m based on processed ICESat data over the UK in order to assess their potential extrapolation across the globe. The accuracy of the TanDEM-X iDEM in UK was obtained as follows: against ICESat GLA14 elevation data, TanDEM-X iDEM has -0.028±3.654 m over England and Wales and 0.316 ± 5.286 m over Scotland for 12 m, -0.073 ± 6.575 m for 30 m, and 0.0225 ± 9.251 m at 90 m. Moreover, 90 % of all results at the three resolutions of TanDEM-X iDEM data (with a linear error at 90 % confidence level) are below 16.2 m. These validation results also indicate that derivative topographic parameters (slope, aspect and relief) have a strong effect on the vertical accuracy of the TanDEM-X iDEMs. In high-relief and large slope terrain, large errors and data voids are frequent, and their location is strongly influenced by topography, whilst in the low- to medium-relief and low slope sites, errors are smaller. ICESat derived elevations are heavily influenced by surface slope within the 70 m footprint as well as there being slope dependent errors in the TanDEM-X iDEMs.

  7. Global Maps from Interferometeric TanDEM-X Data: Applications and Potentials

    Science.gov (United States)

    Rizzoli, Paola; Martone, Michele; Brautigam, Benjamin; Zink, Manfred

    2015-05-01

    TanDEM-X is a spaceborne Synthetic Aperture Radar (SAR) mission, whose goal is the generation of a global Digital Elevation Model (DEM) with unprecedented accuracy, by using interferometric SAR (InSAR) techniques (InSAR). TanDEM-X offers a huge global data set of bistatic InSAR acquisitions, each of them supplemented by quick look images of different SAR quantities, such as amplitude, coherence, and DEM. Global quick look mosaics of the interferometric coherence and of the relative height error can be considered for mission performance monitoring and acquisition strategy optimization. The aim of this paper is to present the use of such mosaics within the TanDEM-X mission and to show their potentials for future scientific applications for example in the fields of glaciology and forestry.

  8. `KombiSens` (combined use of gas sensors with different technologies). Sub-project: Further development of electrochemical gas sensors for applications in sensor heads. Final report; `KombiSens` (Kombinierter Einsatz von Gassensoren verschiedener Technologien). Teilvorhaben: Weiterentwicklung elektrochemischer Gassensoren fuer den Einsatz in Sensorkoepfen. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Bytyn, W.

    1997-04-01

    In the framework of the project `KombiSens - combined application of gas sensors of different technologies`, Messrs. Endress and Hauser worked on the improvement, optimisation or new development of electrochemical and IR photometric gas sensors. (orig./SR) [Deutsch] Im Rahmen des Verbundvorhabens `KombiSens - Kombinierter Einsatz von Gassensoren verschiedener Technologien` wurden von Endress und Hauser elektro-chemische sowie infrarotphotometrische Gassensoren fuer den Einsatz in Sensorsystemen verbessert und anwendungsspezifisch optimiert bzw. neuentwickelt. (orig./SR)

  9. Assoziation des arteriellen Sauerstoffpartialdrucks mit dem Auftreten von Erythroblasten im peripheren Blut von Patienten einer chirurgischen Intensivstation

    OpenAIRE

    Kuert, Sandra

    2012-01-01

    Erythroblasten (EBL) treten im peripheren Blut eines gesunden Erwachsenen gewöhnlich nicht auf. Studien zeigten, dass das Auftreten von EBL bei hospitalisierten Patienten auf ein erhöhtes Mortalitätsrisiko hinweist. Die zugrundeliegenden Mechanismen sind bisher unbekannt. Es ergaben sich Hinweise, dass EBL bei Zuständen von Hypoxie und Inflammation auftreten. Die vorliegende Studie untersucht den Einfluss des arteriellen Sauerstoffpartialdruckes (pO2) auf das Auftreten von EBL ...

  10. Study on the efficiency of thermal refurbishment of residential buildings in Vienna; Bautechnisch-bauphysikalische Beurteilung der Wirksamkeit energetischer Sanierungen am Beispiel staedtischer Wohnhausanlagen in Wien

    Energy Technology Data Exchange (ETDEWEB)

    Maydl, Julia [Zivilingenieurbuero Dr. Maydl, Schindlergasse 6, A-1180 Wien (Austria); Korjenic, Azra [Institut fuer Hochbau und Technologie - Zentrum fuer Bauphysik und Bauakustik, Technische Universitaet Wien, Karlsplatz 13/206-2 A-1040 Wien (Austria); Dreyer, Juergen [TU Wien, Institut fuer Hochbau und Technologie - Zentrum fuer Bauphysik und Bauakustik, Karlsplatz 13/206-2, A-1040 Wien (Austria)

    2007-08-15

    In the framework of the Kyoto Protocol Austria has committed to reduce its greenhouse gas emissions until 2008/2012 by 13% on the base of 1990. Therefore the Federal Government as well as the provincial governments have implemented programs for the protection of climate including several measures to reduce the emission of hazardous greenhouse gases mainly CO{sub 2}. Regarding the enormous potential reduction activities were mainly focused on residential buildings. The refurbishment of the building envelope reduces the heating costs as well as the carbon dioxide emissions and improves the indoor climate. Several investigations were taken to check the utility of thermal refurbishment under structural and physical conditions. Plenty of data available in the line of several expertises of existing residential buildings were analysed and completed by additional investigations. The economic efficiency of thermal insulations is pointed out as well as the period of repayment or the influence of the thickness of insulation on the heating energy demand or possible CO{sub 2}-reductions. (Abstract Copyright [2007], Wiley Periodicals, Inc.) [German] Durch die Verpflichtung Oesterreichs im Zuge der Kyoto-Ziele seine Treibhausgasemissionen um 13% gegenueber dem Basisjahr 1990 zu verringern, entstanden sowohl Klimaschutzprogramme der Bundesregierung als auch der Laender. Die Programme beinhalten verschiedene Massnahmen um den Ausstoss schaedlicher Treibhausgase, allen voran CO{sub 2}, zu minimieren. Ein Schwerpunkt wurde dabei dem Sektor Wohnen und Bauen zugesprochen, da hier sehr viel Potential vorhanden ist. Denn thermisch-energetische Sanierungsmassnahmen haben nicht nur einen positiven Einfluss auf die Energiekennzahl eines Gebaeudes, sondern auch auf die Heizkosten, den CO{sub 2}-Ausstoss und das Raumklima. Im Zuge dieser Arbeit wurden verschiedene Untersuchungen angestellt, um die bautechnisch-bauphysikalische Zweckmaessigkeit thermischer Sanierungen zu ueberpruefen. Neben

  11. Open-Source Digital Elevation Model (DEMs) Evaluation with GPS and LiDAR Data

    Science.gov (United States)

    Khalid, N. F.; Din, A. H. M.; Omar, K. M.; Khanan, M. F. A.; Omar, A. H.; Hamid, A. I. A.; Pa'suya, M. F.

    2016-09-01

    Advanced Spaceborne Thermal Emission and Reflection Radiometer-Global Digital Elevation Model (ASTER GDEM), Shuttle Radar Topography Mission (SRTM), and Global Multi-resolution Terrain Elevation Data 2010 (GMTED2010) are freely available Digital Elevation Model (DEM) datasets for environmental modeling and studies. The quality of spatial resolution and vertical accuracy of the DEM data source has a great influence particularly on the accuracy specifically for inundation mapping. Most of the coastal inundation risk studies used the publicly available DEM to estimated the coastal inundation and associated damaged especially to human population based on the increment of sea level. In this study, the comparison between ground truth data from Global Positioning System (GPS) observation and DEM is done to evaluate the accuracy of each DEM. The vertical accuracy of SRTM shows better result against ASTER and GMTED10 with an RMSE of 6.054 m. On top of the accuracy, the correlation of DEM is identified with the high determination of coefficient of 0.912 for SRTM. For coastal zone area, DEMs based on airborne light detection and ranging (LiDAR) dataset was used as ground truth data relating to terrain height. In this case, the LiDAR DEM is compared against the new SRTM DEM after applying the scale factor. From the findings, the accuracy of the new DEM model from SRTM can be improved by applying scale factor. The result clearly shows that the value of RMSE exhibit slightly different when it reached 0.503 m. Hence, this new model is the most suitable and meets the accuracy requirement for coastal inundation risk assessment using open source data. The suitability of these datasets for further analysis on coastal management studies is vital to assess the potentially vulnerable areas caused by coastal inundation.

  12. The impact of resolution on the accuracy of hydrologic data derived from DEMs

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Hydrologic data derived from digital elevation models (DEM) has been regarded as an effective method in the spatial analysis of geographical information systems (GIS). However, both DEM resolution and terrain complexity has impacts on the accuracy of hydrologic derivatives. In this study, a multi-resolution and multi-relief comparative approach was used as a major methodology to investigate the accuracy of hydrologic data derived from DEMs. The experiment reveals that DEM terrain representation error affects the accuracy of DEM hydrological derivatives (drainage networks and watershed etc.). Coarser DEM resolutions can usually cause worse results. However, uncertain result commonly exists in this calculation. The derivative errors can be found closely related with DEM vertical resolution and terrain roughness. DEM vertical resolution can be found closely related with the accuracy of DEM hydrological derivatives, especially in the smooth plain area. If the mean slope is less than 4 degrees, the derived hydrologic data are usually unreliable. This result may be helpful in estimating the accuracy of the hydrologic derivatives and determining the DEM resolution that is appropriate to the accuracy requirement of a particular user. By applying a threshold value to subset the cells of a higher accumulation flow, a stream network of a specific network density can be extracted. Some very important geomorphologic characteristics, e.g., shallow and deep gullies, can be separately extracted by means of adjusting the threshold value. However, such a flow accumulation based processing method can not correctly derive those streams that pass through the working area because it is hard to accumulate enough flow direction values to express the stream channels at the stream's entrance area. Consequently, errors will definitely occur at the stream's entrance area. In addition, erroneous derivatives can also be found in deriving some particular rivers, e.g., perched (hanging up) rivers

  13. Effect of Uncertainty of Grid DEM on TOPMODEL: Evaluation and Analysis

    Institute of Scientific and Technical Information of China (English)

    WANG Peifa; DU Jinkang; FENG Xuezhi; KANG Guoding

    2006-01-01

    TOPMODEL, a semi-distributed hydrological model, has been widely used. In the process of simulation of the model, Digital Elevation Model (DEM) is used to provide the input data, such as topographic index and distance to the drainage outlet; thus DEM plays an important role in TOPMODEL. This study aims at examining the impacts of DEM uncertainty on the simulation results of TOPMODEL. In this paper, the effects were evaluated mainly from quantitative and qualitative aspects. Firstly, DEM uncertainty was simulated by using the Monte Carlo method, and for every DEM realization, the topographic index and distance to the drainage outlet were extracted. Secondly, the obtained topographic index and the distance to the drainage outlet were input to the TOPMODEL to simulate seven rainstorm-flood events, and four evaluation indices, such as Nash and Sutcliffe efficiency criterion (EFF), sum of squared residuals over all time steps (SSE), sum of squared log residuals over all time steps (SLE) and sum of absolute errors over all time steps (SAE) were recorded. Thirdly, these four evaluation indices were analyzed in statistical manner (minimum, maximum, range, standard deviation and mean value), and effect of DEM uncertainty on TOPMODEL was quantitatively analyzed. Finally, the simulated hydrographs from TOPMODEL using the original DEM and realizations of DEM were qualitatively evaluated under each flood cases. Results show that the effect of DEM uncertainty on TOPMODEL is inconsiderable and could be ignored in the model's application. This can be explained by: 1)TOPMODEL is not sensitive to the distribution of topographic index and distance to the drainage outlet; 2) the distribution of topographic index and distance to the drainage outlet are slightly affected by DEM uncertainty.

  14. Impacts of DEM uncertainties on critical source areas identification for non-point source pollution control based on SWAT model

    Science.gov (United States)

    Xu, Fei; Dong, Guangxia; Wang, Qingrui; Liu, Lumeng; Yu, Wenwen; Men, Cong; Liu, Ruimin

    2016-09-01

    The impacts of different digital elevation model (DEM) resolutions, sources and resampling techniques on nutrient simulations using the Soil and Water Assessment Tool (SWAT) model have not been well studied. The objective of this study was to evaluate the sensitivities of DEM resolutions (from 30 m to 1000 m), sources (ASTER GDEM2, SRTM and Topo-DEM) and resampling techniques (nearest neighbor, bilinear interpolation, cubic convolution and majority) to identification of non-point source (NPS) critical source area (CSA) based on nutrient loads using the SWAT model. The Xiangxi River, one of the main tributaries of Three Gorges Reservoir in China, was selected as the study area. The following findings were obtained: (1) Elevation and slope extracted from the DEMs were more sensitive to DEM resolution changes. Compared with the results of the 30 m DEM, 1000 m DEM underestimated the elevation and slope by 104 m and 41.57°, respectively; (2) The numbers of subwatersheds and hydrologic response units (HRUs) were considerably influenced by DEM resolutions, but the total nitrogen (TN) and total phosphorus (TP) loads of each subwatershed showed higher correlations with different DEM sources; (3) DEM resolutions and sources had larger effects on CSAs identifications, while TN and TP CSAs showed different response to DEM uncertainties. TN CSAs were more sensitive to resolution changes, exhibiting six distribution patterns at all DEM resolutions. TP CSAs were sensitive to source and resampling technique changes, exhibiting three distribution patterns for DEM sources and two distribution patterns for DEM resampling techniques. DEM resolutions and sources are the two most sensitive SWAT model DEM parameters that must be considered when nutrient CSAs are identified.

  15. Effect of DEM Source and Resolution on Extracting River Network and Watershed within Multi-Lake Area in Tibet

    Science.gov (United States)

    Li, Yang; Li, Gang; Lin, Hui

    2014-11-01

    DEM defines drainage structures and basin through conducting overland flow simulation. Two matured DEM Sources are SRTM DEM (Shuttle Radar Topographic Mission) and ASTER GDEM (Advanced Space borne Thermal Emission and Reflection Radiometer Global Digital Elevation Model); The accuracy of hydrological characters that derived from DEM decreased from high resolution to coarse resolution and appeared to be different in different data source (Vaze,Teng, & Spencer, 2010).

  16. Socio-political Turmoil in Mali: The Public Debate Following the Coup d’État on 22 March 2012 Sozio-politische Turbulenzen in Mali: Die öffentliche Debatte nach dem Staatsstreich vom 22. März 2012

    Directory of Open Access Journals (Sweden)

    Sten Hagberg

    2012-01-01

    Full Text Available During the night between 21 and 22 March 2012, a group of young military officers overthrew Mali’s president, Amadou Toumani Touré. The group justified the coup by citing the inability of the regime to both deal with the crisis in the North and provide the army with the appropriate material and manpower to defend the national territory. The coup plunged Mali into violence, and caused a de facto partition of the country. The socio-political turmoil pitting different political and armed factions against each other has continued unabated and has been accompanied by intense mass media debates. In this report we focus on the Malian public debate. By looking at the political class, the international community, and the partition of the country, we analyse representations and stereotypes prevailing in this debate.In der Nacht vom 21. zum 22. März 2012 wurde der Präsident Malis, Amadou Toumani Touré, durch eine Gruppe junger Offiziere gestürzt. Die Gruppe rechtfertigte den Putsch, indem sie auf die Unfähigkeit des Regimes verwies, die Krise im Norden zu bewältigen und die Armee personell und materiell angemessen auszustatten, um die Grenzen das Landes verteidigen zu können. Der Staatsstreich stürzte Mali in eine gewaltsame Auseinandersetzung und führte zu einer faktischen Teilung des Landes. Die sozio-politischen Turbulenzen, in denen verschiedene politische und bewaffnete Gruppierungen gegeneinander antraten, haben seither unvermindert angehalten und wurden von intensiven Debatten in den Massenmedien begleitet. Der vorliegende Bericht konzentriert sich auf die öffentliche Debatte in Mali. Vor dem Hintergrund der politischen Entwicklung des Landes, der Positionen der internationalen Gemeinschaft und der Ursachen für die Teilung des Landes stellen die Autoren die Darstellungsweisen und Stereotypen dar, die in dieser Debatte Verwendung finden.

  17. How Strong and Weak Readers Perform on the Developmental Eye Movement Test (DEM): Norms for Latvian School-Aged Children

    Science.gov (United States)

    Serdjukova, Jelena; Ekimane, Lasma; Valeinis, Janis; Skilters, Jurgis; Krumina, Gunta

    2017-01-01

    The aim of our study was to determine DEM test performance norms for school-aged children in Latvia, assess how DEM test results correlate with children's reading rates, compare test performance between strong and weak readers. A modified DEM test and a newly developed reading test were administered to 1487 children during a screening survey. Our…

  18. Incorporating the effect of DEM resolution and accuracy for improved flood inundation mapping

    Science.gov (United States)

    Saksena, Siddharth; Merwade, Venkatesh

    2015-11-01

    Topography plays a major role in determining the accuracy of flood inundation areas. However, many areas in the United States and around the world do not have access to high quality topographic data in the form of Digital Elevation Models (DEM). For such areas, an improved understanding of the effects of DEM properties such as horizontal resolution and vertical accuracy on flood inundation maps may eventually lead to improved flood inundation modeling and mapping. This study attempts to relate the errors arising from DEM properties such as spatial resolution and vertical accuracy to flood inundation maps, and then use this relationship to create improved flood inundation maps from coarser resolution DEMs with low accuracy. The results from the five stream reaches used in this study show that water surface elevations (WSE) along the stream and the flood inundation area have a linear relationship with both DEM resolution and accuracy. This linear relationship is then used to extrapolate the water surface elevations from coarser resolution DEMs to get water surface elevations corresponding to a finer resolution DEM. Application of this approach show that improved results can be obtained from flood modeling by using coarser and less accurate DEMs, including public domain datasets such as the National Elevation Dataset and Shuttle Radar Topography Mission (SRTM) DEMs. The improvement in the WSE and its application to obtain better flood inundation maps is dependent on the study reach characteristics such as land use, valley shape, reach length and width. Application of the approach presented in this study on more reaches may lead to development of guidelines for flood inundation mapping using coarser resolution and less accurate topographic datasets.

  19. Improving Cartosat-1 DEM accuracy using synthetic stereo pair and triplet

    Science.gov (United States)

    Giribabu, D.; Srinivasa Rao, S.; Krishna Murthy, Y. V. N.

    2013-03-01

    Cartosat-1 is the first Indian Remote Sensing Satellite capable of providing along-track stereo images. Cartosat-1 provides forward stereo images with look angles +26° and -5° with respect to nadir for generating Digital Elevation Models (DEMs), Orthoimages and value added products for various applications. A pitch bias of -21° to the satellite resulted in giving reverse tilt mode stereo pair with look angles of +5° and -26° with respect to nadir. This paper compares DEMs generated using forward, reverse and other possible synthetic stereo pairs for two different types of topographies. Stereo triplet was used to generate DEM for Himalayan mountain topography to overcome the problem of occlusions. For flat to undulating topography it was shown that using Cartosat-1 synthetic stereo pair with look angles of -26° and +26° will produce improved version of DEM. Planimetric and height accuracy (Root Mean Square Error (RMSE)) of less than 2.5 m and 2.95 m respectively were obtained and qualitative analysis shows finer details in comparison with other DEMs. For rugged terrain and steep slopes of Himalayan mountain topography simple stereo pairs may not provide reliable accuracies in DEMs due to occlusions and shadows. Stereo triplet from Cartosat-1 was used to generate DEM for mountainous topography. This DEM shows better reconstruction of elevation model even at occluded region when compared with simple stereo pair based DEM. Planimetric and height accuracy (RMSE) of nearly 3 m were obtained and qualitative analysis shows reduction of outliers at occluded region.

  20. Evaluation of topographic index in relation to terrain roughness and DEM grid spacing

    Indian Academy of Sciences (India)

    Samadrita Mukherjee; Sandip Mukherjee; R D Garg; A Bhardwaj; P L N Raju

    2013-06-01

    Topographic index is an important attribute of digital elevation model (DEM) which indicates soil saturation. It is used for estimation of run-off, soil moisture, depth of ground water and hydrological simulation. Topographic index is derived from DEMs; hence the accuracy of DEM influences its computation. Commonly the raster based grid DEM is widely used to simulate hydrological model parameter, and accuracy varies with respect to DEM grid size and morphological characteristics of terrain. In this study topographic index is evaluated in terms of DEM grid size and terrain roughness. The study was carried out on four small watersheds, having different roughness characteristics, located over the Himalayan terrain. Topographic index surface is derived for each watershed from different grid spacing DEM (10–150 m), analysed and validated. It is found that DEM grid spacing affects the topographic index. The surface representation is smooth in the coarse grid spacing and the pattern of topographic index changes with grid spacing. The spatial autocorrelation of topographic index surface reduces when calculated from larger spacing DEM. The mean of the topographic index surface increases and standard deviation decreases with the increase of grid spacing and the effect is more pronounced in the rough terrain. Accuracy of the topographic index is also evaluated with respect to grid spacing and terrain roughness by comparing the topographic index surface with respect to reference data (10 m grid spacing topographic index surface). The RMSE and mean error of topographic index surface increases in larger grid spacing and the effect is more in rugged terrain.

  1. Effective simulation of flexible lateral boundaries in two-and three-dimensional DEM simulations

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Discrete element method (DEM) models to simulate laboratory element tests play an important role in advancing our understanding of the mechanics of granular material response, including bonded or cemented, particulate materials.Comparisons of the macro-scale response observed in a real physical test and a "virtual" DEM-simulated test can calibrate or validate DEM models.The detailed, particle scale information provided in the DEM simulation can then be used to develop our understanding of the material behaviour.It is important to accurately model the physical test boundary conditions in these DEM simulations.This paper specifically considers triaxial tests as these tests are commonly used in soil mechanics.In a triaxial test,the test specimen of granular material is enclosed within a flexible latex membrane that allows the material to deform freely during testing, while maintaining a specified stress condition. Triaxial tests can only be realistically simulated in 3D DEM codes, however analogue,2D, biaxial DEM simulations are also often considered as it is easier to visualize particle interactions in two dimensions. This paper describes algorithms to simulate the lateral boundary conditions imposed by the latex membrane used in physical triaxial tests in both 2D and 3D DEM simulations.The importance of carefully considering the lateral boundary conditions in DEM simulations is illustrated by considering a 2D biaxial test on a specimen of frictional unbonded disks and a 3D triaxial test on a bonded (cemented) specimen of spheres. The comparisons indicate that the lateral boundary conditions have a more significant influence on the local,particle-scale response in comparison with the overall macro-scale observations.

  2. TanDEM-X双站SAR干涉测量及研究进展%TanDEM-X bistatic SAR interferometry and its research progress

    Institute of Scientific and Technical Information of China (English)

    孙亚飞; 江利明; 柳林; 孙永玲; 汪汉胜

    2015-01-01

    This paper comprehensively describes the scientific research plan of the TanDEM -X/TerraSAR -X bistatic SAR mission, with emphasis placed on its scientific objectives, TanDEM-X satellite parameters, orbital configuration and data acquisition modes. Then, the advantages of the new InSAR techniques including bistatic SAR, Pol-InSAR and digital beam forming are briefly discussed and the progress of the techniques of TanDEM-X bistatic SAR interferometry is analyzed. These new SAR techniques will greatly promote the application potential of SAR interferometry in Earth sciences such as global topography mapping, glaciology, oceanography and geology.%较全面、系统地介绍了TanDEM-X/TerraSAR-X双站SAR科学计划,重点涉及其科学目标、TanDEM-X卫星参数、轨道结构以及干涉数据获取模式等相关内容,并讨论了双站SAR成像、极化InSAR和数字波束成形等干涉测量新技术及其研究进展。这些双站SAR新技术的实现将大大地推动SAR干涉测量在全球地形测绘、冰川学、海洋学及地质学等领域中的应用。

  3. DEM Simulation of Particle Clogging in Fiber Filtration

    Science.gov (United States)

    Tao, Ran; Yang, Mengmeng; Li, Shuiqing

    2015-11-01

    The formation of porous particle deposits plays a crucial role in determining the efficiency of filtration process. In this work, an adhesive discrete element method (DEM), in combination with CFD, is developed to dynamically describe these porous deposit structures and the changed flow field between two parallel fibers under the periodic boundary conditions. For the first time, it is clarified that the structures of clogged particles are dependent on both the adhesion parameter (defined as the ratio of interparticle adhesion to particle inertia) and the Stokes number (as an index of impaction efficiency). The relationship between the pressure-drop gradient and the coordination number along the filtration time is explored, which can be used to quantitatively classify the different filtration regimes, i.e., clean filter stage, clogging stage and cake filtration stage. Finally, we investigate the influence of the fiber separation distance on the particle clogging behavior, which affects the collecting efficiency of the fibers significantly. The results suggest that changing the arrangement of fibers can improve the filter performance. This work has been funded by the National Key Basic Research and Development Program (2013CB228506).

  4. Modelling die filling with charged particles using DEM/CFD

    Institute of Scientific and Technical Information of China (English)

    Emmanuel Nkem Nwose; Chunlei Pei; Chuan-Yu Wu

    2012-01-01

    The effects of electrostatic charge on powder flow behaviour during die filling in a vacuum and in air were analysed using a coupled discrete element method and computational fluid dynamics (DEM/CFD) code,in which long range electrostatic interactions were implemented.The present 2D simulations revealed that both electrostatic charge and the presence of air can affect the powder flow behaviour during die filling.It was found that the electrostatic charge inhibited the flow of powders into the die and induced a loose packing structure.At the same filling speed,increasing the electrostatic charge led to a decrease in the fill ratio which quantifies the volumetric occupancy of powder in the die.In addition,increasing the shoe speed caused a further decrease in the fill ratio,which was characterised using the concept of critical filling speed.When the electrostatic charge was low,the air/particle interaction was strong so that a lower critical filling speed was obtained for die filling in air than in a vacuum.With high electrostatic charge,the electrostatic interactions became dominant.Consequently,similar fill ratio and critical filling speed were obtained for die filling in air and in a vacuum.

  5. Evaluation of DEM generation accuracy from UAS imagery

    Science.gov (United States)

    Santise, M.; Fornari, M.; Forlani, G.; Roncella, R.

    2014-06-01

    The growing use of UAS platform for aerial photogrammetry comes with a new family of Computer Vision highly automated processing software expressly built to manage the peculiar characteristics of these blocks of images. It is of interest to photogrammetrist and professionals, therefore, to find out whether the image orientation and DSM generation methods implemented in such software are reliable and the DSMs and orthophotos are accurate. On a more general basis, it is interesting to figure out whether it is still worth applying the standard rules of aerial photogrammetry to the case of drones, achieving the same inner strength and the same accuracies as well. With such goals in mind, a test area has been set up at the University Campus in Parma. A large number of ground points has been measured on natural as well as signalized points, to provide a comprehensive test field, to check the accuracy performance of different UAS systems. In the test area, points both at ground-level and features on the buildings roofs were measured, in order to obtain a distributed support also altimetrically. Control points were set on different types of surfaces (buildings, asphalt, target, fields of grass and bumps); break lines, were also employed. The paper presents the results of a comparison between two different surveys for DEM (Digital Elevation Model) generation, performed at 70 m and 140 m flying height, using a Falcon 8 UAS.

  6. Applying the Artificial Neural Network to Predict the Soil Responses in the DEM Simulation

    Science.gov (United States)

    Li, Z.; Chow, J. K.; Wang, Y. H.

    2017-06-01

    This paper aims to bridge the soil properties and the soil response in the discrete element method (DEM) simulation using the artificial neural network (ANN). The network was designed to output the stress-strain-volumetric response from inputting the soil properties. 31 biaxial shearing tests with varying soil parameters were generated using the DEM simulations. Based on these 31 training samples, a three-layer neural network was established. 2 extra samples were generated to examine the validity of the network, and the predicted curves using the ANN were well matched with those from the DEM simulations. Overall, the ANN was found promising in effectively modelling the soil behaviour.

  7. Simulation of the Surface Hydrology of Dalinghe Watershed Automatically Based on SRTM DEM

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    [Objective] The aim was to simulate the surface water flow of Dalinghe watershed based on SRTM DEM.[Method] By using ArcGIS ModelBuilder,and SRTM DEM data of Dalinghe watershed as input data,the model to simulate the water flow of Dalinghe watershed was set up.[Result] The model realized automatic division of Dalinghe watershed area and extraction of stream network.In the meantime,it also made the choice of threshold during filling DEM and extracting stream network much easier.The division of the Dalinghe w...

  8. Der Einfluss von akustischen und nicht-akustischen Parametern auf die Fluglärmbelästigung während kurzer Zeitintervalle – Ergebnisse der COSMA-Feldstudie am Flughafen Köln/Bonn

    OpenAIRE

    Bartels, S.; Müller, U.

    2014-01-01

    Eine Vielzahl an Feldstudien hat bislang den Einfluss akustischer und nicht-akustischer Variablen auf die Langzeitbelästigung durch Fluglärm untersucht. Die Zahl der Studien, die den Fokus auf die Kurzzeitbelästigung legten, ist dagegen sehr klein. Im Rahmen des EU-Projektes COSMA (Community Oriented Solutions to Minimise aircraft noise Annoyance) beurteilten 55 Anwohner des Flughafens Köln/Bonn (M = 45,7 Jahre, SD ± 14,3, 34 Frauen) über einen Zeitraum von vier Tagen in stündlichen Intervall...

  9. Coastal Topography--Northeast Atlantic Coast, Post-Hurricane Sandy, 2012: Digital elevation model (DEM)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A DEM was produced for a portion of the New York, Delaware, Maryland, Virginia, and North Carolina coastlines, post-Hurricane Sandy (Sandy was an October 2012...

  10. Digital Elevation Model (DEM), Topographic survey of Eureka Township, Published in unknown, Eureka County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Digital Elevation Model (DEM) dataset, was produced all or in part from Field Survey/GPS information as of unknown. It is described as 'Topographic survey of...

  11. VT Lidar Hydro-flattened DEM (1.6 meter) - 2008 - West Franklin

    Data.gov (United States)

    Vermont Center for Geographic Information — (Link to Metadata) This metadata applies to the following collection area(s): Missisquoi Lower 2008 1.6m and Digital Elevation Model (DEM) datasets of various...

  12. Digital elevation models (DEMs) of the Elwha River delta, Washington, September 2013

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of the data release presents a digital elevation model (DEM) derived from bathymetry and topography data of the Elwha River delta collected in September...

  13. A seamless, high-resolution, coastal digital elevation model (DEM) for Southern California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A seamless, three-meter digital elevation model (DEM) was constructed for the entire Southern California coastal zone, extending 473 km from Point Conception to the...

  14. Digital elevation models (DEMs) of the Elwha River delta, Washington, May 2011

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of the data release presents a digital elevation model (DEM) derived from bathymetry and topography data of the Elwha River delta collected in May 2011....

  15. VT Lidar Hydro-flattened DEM (1.6 meter) - 2010 - East Franklin/West Orleans

    Data.gov (United States)

    Vermont Center for Geographic Information — (Link to Metadata) This metadata applies to the following collection area(s): Missisquoi Upper 2010 1.6m and Digital Elevation Model (DEM) datasets of various...

  16. VT Lidar Hydro-flattened DEM (0.7 meter) - 2014 - Chittenden, Lamoille, Orleans, & Washington Counties

    Data.gov (United States)

    Vermont Center for Geographic Information — (Link to Metadata) This metadata applies to the following collection area(s): Eastern VT 2014 0.7m and Digital Elevation Model (DEM) dataset of the following...

  17. VT Lidar Hydro-flattened DEM (0.7 meter) - 2015 - Windham County

    Data.gov (United States)

    Vermont Center for Geographic Information — (Link to Metadata) This metadata applies to the following collection area(s): Windham County 2015 0.7m and Digital Elevation Model (DEM) dataset of the following...

  18. Digital elevation models (DEMs) of the Elwha River delta, Washington, August 2011

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of the data release presents a digital elevation model (DEM) derived from bathymetry and topography data of the Elwha River delta collected in August 2011....

  19. Digital Elevation Model (DEM), Published in unknown, DeKalb County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Digital Elevation Model (DEM) dataset, was produced all or in part from LIDAR information as of unknown. Data by this publisher are often provided in State...

  20. VT Lidar Hydro-flattened DEM (1.6 meter) - 2012 - Addison

    Data.gov (United States)

    Vermont Center for Geographic Information — (Link to Metadata) This metadata applies to the following collection area(s): Addison County 2012 1.6m and Digital Elevation Model (DEM) datasets of various...

  1. A Vector-based Method for the Extraction of Catchment from Grid DEMs

    Institute of Scientific and Technical Information of China (English)

    ZHU Qing; TIAN Yixiang

    2005-01-01

    The methodology of catchment extraction especially from regular grid digital elevation models (DEMs) is briefly reviewed.Then an efficient algorithm, which combines vector process and traditional neighbourhood raster process, is designed for extracting the catchments and subcatchments from depressionless DEMs.The catchment area of each river in the grid DEM data is identified and delineated, then is divided into subcatchments as required.Compared to traditional processes, this method for identifying catchments focuses on the boundaries instead of the area inside the catchments and avoids the boundary intersection phenomena.Last, the algorithm is tested with a set of DEMs of different sizes, and the result proves that the computation efficiency and accuracy are better than existent methods.

  2. A seamless, high-resolution, coastal digital elevation model (DEM) for Southern California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A seamless, three-meter digital elevation model (DEM) was constructed for the entire Southern California coastal zone, extending 473 km from Point Conception to the...

  3. Digital elevation models (DEMs) of the Elwha River delta, Washington, July 2016

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of the data release presents a digital elevation model (DEM) derived from bathymetry and topography data of the Elwha River delta collected in July 2016....

  4. Digital elevation models (DEMs) of the Elwha River delta, Washington, September 2010

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of the data release presents a digital elevation model (DEM) derived from bathymetry and topography data of the Elwha River delta collected in September...

  5. Digital elevation models (DEMs) of the Elwha River delta, Washington, August 2012

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of the data release presents a digital elevation model (DEM) derived from bathymetry and topography data of the Elwha River delta collected in August 2012....

  6. Como diagnosticar as quatro causas mais freqüentes de demência?

    OpenAIRE

    Caramelli Paulo; Barbosa Maira Tonidandel

    2002-01-01

    Doença de Alzheimer, demência vascular, demência com corpos de Lewy e demência frontotemporal são as quatro causas mais freqüentes de demência na prática clínica. O diagnóstico diferencial dessas condições se baseia na busca de perfis clínicos característicos por anamnese adequada, exame neurológico e avaliação neuropsicológica, além de investigação complementar pertinente, que consiste em exames laboratoriais e de neuroimagem. O presente artigo apresenta breve revisão das características pri...

  7. On the potential of very high-resolution repeat DEMs in glacial and periglacial environments

    Directory of Open Access Journals (Sweden)

    J. Abermann

    2010-01-01

    Full Text Available The potential of high-resolution repeat DEMs was investigated for glaciological applications including periglacial features (e.g. rock glaciers. It was shown that glacier boundaries can be delineated using airborne LIDAR-DEMs as a primary data source and that information on debris cover extent could be extracted using multi-temporal DEMs. Problems and limitations are discussed, and accuracies quantified. Absolute deviations of airborne laser scanning (ALS derived glacier boundaries from ground-truthed ones were below 4 m for 80% of the ground-truthed values. Overall, we estimated an accuracy of +/−1.5% of the glacier area for glaciers larger than 1 km2. The errors in the case of smaller glaciers did not exceed +/−5% of the glacier area. The use of repeat DEMs in order to obtain information on the extent, characteristics and activity of rock glaciers was investigated and discussed based on examples.

  8. San Francisco Bay-Delta bathymetric/topographic digital elevation model(DEM)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A high-resolution (10-meter per pixel) digital elevation model (DEM) was created for the Sacramento-San Joaquin Delta using both bathymetry and topography data. This...

  9. Hydrologic validation of a structure-from-motion DEM derived from low-altitude UAV imagery

    Science.gov (United States)

    Steiner, Florian; Marzolff, Irene; d'Oleire-Oltmanns, Sebastian

    2015-04-01

    The increasing ease of use of current Unmanned Aerial Vehicles (UAVs) and 3D image processing software has spurred the number of applications relying on high-resolution topographic datasets. Of particular significance in this field is "structure from motion" (SfM), a photogrammetric technique used to generate low-cost digital elevation models (DEMs) for erosion budgeting, measuring of glaciers/lava-flows, archaeological applications and others. It was originally designed to generate 3D-models of buildings, based on unordered collections of images and has become increasingly common in geoscience applications during the last few years. Several studies on the accuracy of this technique already exist, in which the SfM data is mostly compared with Lidar-generated terrain data. The results are mainly positive, indicating that the technique is suitable for such applications. This work aims at validating very high resolution SfM DEMs with a different approach: Not the original elevation data is validated, but data on terrain-related hydrological and geomorphometric parameters derived from the DEM. The study site chosen for this analysis is an abandoned agricultural field near the city of Taroudant, in the semi-arid southern part of Morocco. The site is characterized by aggressive rill and gully erosion and is - apart from sparsely scattered shrub cover - mainly featureless. An area of 5.7 ha, equipped with 30 high-precision ground control points (GCPs), was covered with an unmanned aerial vehicle (UAV) in two different heights (85 and 170 m). A selection of 160 images was used to generate several high-resolution DEMs (2 and 5 cm resolution) of the area using the fully automated SfM software AGISOFT Photoscan. For comparison purposes, a conventional photogrammetry-based workflow using the Leica Photogrammetry Suite was used to generate a DEM with a resolution of 5 cm (LPS DEM). The evaluation is done by comparison of the SfM DEM with the derived orthoimages and the LPS DEM

  10. Processing, validating, and comparing DEMs for geomorphic application on the Puna de Atacama Plateau, northwest Argentina

    Science.gov (United States)

    Purinton, Benjamin; Bookhagen, Bodo

    2016-04-01

    This study analyzes multiple topographic datasets derived from various remote-sensing methods from the Pocitos Basin of the central Puna Plateau in northwest Argentina at the border to Chile. Here, the arid climate and clear atmospheric conditions and lack of vegetation provide ideal conditions for remote sensing and Digital Elevation Model (DEM) comparison. We compare the following freely available DEMs: SRTM-X (spatial resolution of ~30 m), SRTM-C v4.1 (90 m), and ASTER GDEM2 (30 m). Additional DEMs for comparison are generated from optical and radar datasets acquired freely (ASTER Level 1B stereo pairs and Sentinal-1A radar), through research agreements (RapidEye Level 1B scenes, ALOS radar, and ENVISAT radar), and through commercial sources (TerraSAR-X / TanDEM-X radar). DEMs from ASTER (spatial resolution of 15 m) and RapidEye (~5-10 m) optical datasets are produced by standard photogrammetric techniques and have been post-processed for validation and alignment purposes. Because RapidEye scenes are captured at a low incidence angle (validated against over 400,000 differential GPS (dGPS) measurements gathered during four field campaigns in 2012 and 2014 to 2016. Of these points, more than 250,000 lie within the Pocitos Basin with average vertical and horizontal accuracies of 0.95 m and 0.69 m, respectively. Dataset accuracy is judged by the lowest standard deviations of elevation compared with the dGPS data and with the SRTM-X control DEM. Of particular interest in the field of quantitative geomorphology are topometrics (e.g., relief, channel steepness, and hillslope concavity) derived from the DEMs. The accuracy of these metrics is partly dependent on the overall DEM accuracy, but also on the accuracy of the depiction of the river network (a small areal fraction of the DEM). In addition, several topometrics depend on the first and second derivative of elevation (slope and curvature), which are affected by DEM accuracy and noise. In light of these issues

  11. Glacier Volume Change Estimation Using Time Series of Improved Aster Dems

    Science.gov (United States)

    Girod, Luc; Nuth, Christopher; Kääb, Andreas

    2016-06-01

    Volume change data is critical to the understanding of glacier response to climate change. The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) system embarked on the Terra (EOS AM-1) satellite has been a unique source of systematic stereoscopic images covering the whole globe at 15m resolution and at a consistent quality for over 15 years. While satellite stereo sensors with significantly improved radiometric and spatial resolution are available to date, the potential of ASTER data lies in its long consistent time series that is unrivaled, though not fully exploited for change analysis due to lack of data accuracy and precision. Here, we developed an improved method for ASTER DEM generation and implemented it in the open source photogrammetric library and software suite MicMac. The method relies on the computation of a rational polynomial coefficients (RPC) model and the detection and correction of cross-track sensor jitter in order to compute DEMs. ASTER data are strongly affected by attitude jitter, mainly of approximately 4 km and 30 km wavelength, and improving the generation of ASTER DEMs requires removal of this effect. Our sensor modeling does not require ground control points and allows thus potentially for the automatic processing of large data volumes. As a proof of concept, we chose a set of glaciers with reference DEMs available to assess the quality of our measurements. We use time series of ASTER scenes from which we extracted DEMs with a ground sampling distance of 15m. Our method directly measures and accounts for the cross-track component of jitter so that the resulting DEMs are not contaminated by this process. Since the along-track component of jitter has the same direction as the stereo parallaxes, the two cannot be separated and the elevations extracted are thus contaminated by along-track jitter. Initial tests reveal no clear relation between the cross-track and along-track components so that the latter seems not to be

  12. HELI-DEM portal for geo-processing services

    Science.gov (United States)

    Cannata, Massimiliano; Antonovic, Milan; Molinari, Monia

    2014-05-01

    HELI-DEM (Helvetia-Italy Digital Elevation Model) is a project developed in the framework of Italy/Switzerland Operational Programme for Trans-frontier Cooperation 2007-2013 whose major aim is to create a unified digital terrain model that includes the alpine and sub-alpine areas between Italy and Switzerland. The partners of the project are: Lombardy Region, Piedmont Region, Polytechnic of Milan, Polytechnic of Turin and Fondazione Politecnico from Italy; Institute of Earth Sciences (SUPSI) from Switzerland. The digital terrain model has been produced by integrating and validating the different elevation data available for the areas of interest, characterized by different reference frame, resolutions and accuracies: DHM at 25 m resolution from Swisstopo, DTM at 20 m resolution from Lombardy Region, DTM at 5 m resolution from Piedmont Region and DTM LiDAR PST-A at about 1 m resolution, that covers the main river bed areas and is produced by the Italian Ministry of the Environment. Further results of the project are: the generation of a unique Italian Swiss geoid with an accuracy of few centimeters (Gilardoni et al. 2012); the establishment of a GNSS permanent network, prototype of a transnational positioning service; the development of a geo-portal, entirely based on open source technologies and open standards, which provides the cross-border DTM and offers some capabilities of analysis and processing through the Internet. With this talk, the authors want to present the main steps of the project with a focus on the HELI-DEM geo-portal development carried out by the Institute of Earth Sciences, which is the access point to the DTM outputted from the project. The portal, accessible at http://geoservice.ist.supsi.ch/helidem, is a demonstration of open source technologies combined for providing access to geospatial functionalities to wide non GIS expert public. In fact, the system is entirely developed using only Open Standards and Free and Open Source Software (FOSS

  13. ASTER Global DEM contribution to GEOSS demonstrates open data sharing

    Science.gov (United States)

    Sohre, T.; Duda, K. A.; Meyer, D. J.; Behnke, J.; Nasa Esdis Lp Daac

    2010-12-01

    across all the GEOSS Societal Benefit areas was shown. The release of the global tiled research-grade DEM resulted in a significant increase in demand for ASTER elevation models, and increased awareness of related products. No cost access to these data has also promoted new applications of remotely sensed data, increasing their use across the full range of the GEOSS societal benefit areas. In addition, the simplified data access and greatly expanded pool of users resulted in a number of suggestions from researchers in many disciplines for possible enhancements to future versions of the ASTER GDEM. The broad distribution of the product can be directly attributed to the adoption of fundamental GEOSS data sharing principles, which are directed toward expanded access by minimizing time delay and cost, thus facilitating data use for education, research, and a range of other applications. The ASTER GDEM demonstrated the need and user demand for an improved global DEM product as well as the added benefit of not only “full and open” distribution, but “free and open” distribution.

  14. DEM simulation of granular flows in a centrifugal acceleration field

    Science.gov (United States)

    Cabrera, Miguel Angel; Peng, Chong; Wu, Wei

    2017-04-01

    The main purpose of mass-flow experimental models is abstracting distinctive features of natural granular flows, and allow its systematic study in the laboratory. In this process, particle size, space, time, and stress scales must be considered for the proper representation of specific phenomena [5]. One of the most challenging tasks in small scale models, is matching the range of stresses and strains among the particle and fluid media observed in a field event. Centrifuge modelling offers an alternative to upscale all gravity-driven processes, and it has been recently employed in the simulation of granular flows [1, 2, 3, 6, 7]. Centrifuge scaling principles are presented in Ref. [4], collecting a wide spectrum of static and dynamic models. However, for the case of kinematic processes, the non-uniformity of the centrifugal acceleration field plays a major role (i.e., Coriolis and inertial effects). In this work, we discuss a general formulation for the centrifugal acceleration field, implemented in a discrete element model framework (DEM), and validated with centrifuge experimental results. Conventional DEM simulations relate the volumetric forces as a function of the gravitational force Gp = mpg. However, in the local coordinate system of a rotating centrifuge model, the cylindrical centrifugal acceleration field needs to be included. In this rotating system, the centrifugal acceleration of a particle depends on the rotating speed of the centrifuge, as well as the position and speed of the particle in the rotating model. Therefore, we obtain the formulation of centrifugal acceleration field by coordinate transformation. The numerical model is validated with a series of centrifuge experiments of monodispersed glass beads, flowing down an inclined plane at different acceleration levels and slope angles. Further discussion leads to the numerical parameterization necessary for simulating equivalent granular flows under an augmented acceleration field. The premise of

  15. The topographic grain concept in DEM-based geomorphometric mapping

    Science.gov (United States)

    Józsa, Edina

    2016-04-01

    A common drawback of geomorphological analyses based on digital elevation datasets is the definition of search window size for the derivation of morphometric variables. The fixed-size neighbourhood determines the scale of the analysis and mapping, which can lead to the generalization of smaller surface details or the elimination of larger landform elements. The methods of DEM-based geomorphometric mapping are constantly developing into the direction of multi-scale landform delineation, but the optimal threshold for search window size is still a limiting factor. A possible way to determine the suitable value for the parameter is to consider the topographic grain principle (Wood, W. F. - Snell, J. B. 1960, Pike, R. J. et al. 1989). The calculation is implemented as a bash shell script for GRASS GIS to determine the optimal threshold for the r.geomorphon module. The approach relies on the potential of the topographic grain to detect the characteristic local ridgeline-to-channel spacing. By calculating the relative relief values with nested neighbourhood matrices it is possible to define a break-point where the increase rate of local relief encountered by the sample is significantly reducing. The geomorphons approach (Jasiewicz, J. - Stepinski, T. F. 2013) is a cell-based DEM classification method for the identification of landform elements at a broad range of scales by using line-of-sight technique. The landforms larger than the maximum lookup distance are broken down to smaller elements therefore the threshold needs to be set for a relatively large value. On the contrary, the computational requirements and the size of the study sites determine the upper limit for the value. Therefore the aim was to create a tool that would help to determine the optimal parameter for r.geomorphon tool. As a result it would be possible to produce more objective and consistent maps with achieving the full efficiency of this mapping technique. For the thorough analysis on the

  16. An improved method to represent DEM uncertainty in glacial lake outburst flood propagation using stochastic simulations

    Science.gov (United States)

    Watson, Cameron S.; Carrivick, Jonathan; Quincey, Duncan

    2015-10-01

    Modelling glacial lake outburst floods (GLOFs) or 'jökulhlaups', necessarily involves the propagation of large and often stochastic uncertainties throughout the source to impact process chain. Since flood routing is primarily a function of underlying topography, communication of digital elevation model (DEM) uncertainty should accompany such modelling efforts. Here, a new stochastic first-pass assessment technique was evaluated against an existing GIS-based model and an existing 1D hydrodynamic model, using three DEMs with different spatial resolution. The analysis revealed the effect of DEM uncertainty and model choice on several flood parameters and on the prediction of socio-economic impacts. Our new model, which we call MC-LCP (Monte Carlo Least Cost Path) and which is distributed in the supplementary information, demonstrated enhanced 'stability' when compared to the two existing methods, and this 'stability' was independent of DEM choice. The MC-LCP model outputs an uncertainty continuum within its extent, from which relative socio-economic risk can be evaluated. In a comparison of all DEM and model combinations, the Shuttle Radar Topography Mission (SRTM) DEM exhibited fewer artefacts compared to those with the Advanced Spaceborne Thermal Emission and Reflection Radiometer Global Digital Elevation Model (ASTER GDEM), and were comparable to those with a finer resolution Advanced Land Observing Satellite Panchromatic Remote-sensing Instrument for Stereo Mapping (ALOS PRISM) derived DEM. Overall, we contend that the variability we find between flood routing model results suggests that consideration of DEM uncertainty and pre-processing methods is important when assessing flow routing and when evaluating potential socio-economic implications of a GLOF event. Incorporation of a stochastic variable provides an illustration of uncertainty that is important when modelling and communicating assessments of an inherently complex process.

  17. Monitoring lava dome changes by means of differential DEMs from TanDEM-X interferometry: Examples from Merapi, Indonesia and Volcán de Colima, Mexico

    Science.gov (United States)

    Kubanek, J.; Westerhaus, M.; Heck, B.

    2013-12-01

    Estimating the amount of erupted material during a volcanic crisis is one of the major challenges in volcano research. One way to do this and to discriminate between juvenile and non-juvenile fraction is to assess topographic changes before and after an eruption while using area-wide 3D data. LiDAR or other airborne systems may be a good source, but the recording fails when clouds due to volcanic activity obstruct the sight. In addition, costs as well as logistics are high for local observatories. When dealing with dome-building volcanoes, acquiring the data gets further complicated. As the volcano dome can change rapidly in active phases, it is nearly impossible to collect data at the right time. However, when dealing with gross volume change estimates, at least two data sets - taken directly before and after the eruption - are essential. The innovative German Earth observation mission TanDEM-X (TerraSAR-X add-on for Digital Elevation Measurement) is of great importance to overcome some of these problems. The two almost identical radar satellites TerraSAR-X and TanDEM-X fly in a close formation, thus recording images of the same place on the Earth surface at the same time (bistatic mode). As the radar signal penetrates clouds, digital elevation models (DEMs) of the area of investigation can be generated without problems even with cloud cover. A time series analysis of the differential DEMs therefore opens the possibility to assess volume changes at active lava domes. We choose Merapi in Indonesia and Volcán de Colima in Mexico as test sites. Both volcanoes reside in a state of long term effusive eruption, interrupted every few years by phases of dome destruction, generation of pyroclastic flows and deposition of volcanic material. The availability of extensive ground truth data for both test sites further enables to validate the spaceborne data and results. Here, we analyze lava dome changes due to the hazardous Merapi 2010 eruption. We show a series of DEMs

  18. Influence of phosphorus elimination on sludge treatment and sludge usage at municipal wastewater treatment plants; Einfluss von P-Eliminierungsverfahren auf Schlammbehandlung und -verwertung bei der kommunalen Abwasserreinigung

    Energy Technology Data Exchange (ETDEWEB)

    Poepel, H.J.; Jardin, N.

    1995-01-01

    .) [Deutsch] Im ersten Teil der Arbeit wird der Einfluss der erhoehten biologischen Phosphorelimination auf den Ueberschussschlammanfall, die Phosphorrueckloesung waehrend der Schlammbehandlung und die daraus resultierende P-Rueckbelastung untersucht. Dazu wurden umfangreiche Versuche im halbtechnischen Massstab mit verschiedenen Eindickungssystemen (Zentrifuge, Siebtrommel und Schwerkrafteindickung) und Stabilisierungsverfahren (anaerob-mesophile und aerob-thermophile Stabilisation) durchgefuehrt. Bei der erhoehten biologischen Phosphorelimination wurde, bedingt durch die Einlagerung von Phosphor in Form von Polyphosphat, ein zusaetzlicher Schlammanfall von etwa 3 g TS/g P gefunden. Alle untersuchten Verfahren der getrennten Ueberschussschlammeindickung verursachten nur eine geringe P-Rueckbelastung. Bei beiden Stabilisierungsverfahren wurde das Polyphosphat vollstaendig hydrolysiert und Phosphat freigesetzt. Durch Ausfaelle von Struvit (Magnesium-Ammonium-Phosphat) und Adsorptionsreaktionen wurde jedoch ein grosser Teil des freigesetzten Phosphats refixiert, so dass die resultierende P-Rueckbelastung meist unter 20% der P-Zulauffracht lag. Auf Basis der durchgefuehrten Versuche wurde ein kinetisches Modell zur Beschreibung von Phosphatrueckloesung und -fixierung entwickelt. Im zweiten Teil der Arbeit wird der Einfluss der chemisch-physikalischen Phosphorelemination auf Schlammanfall und P-Rueckloesung waehrend der Schlammbehandlung untersucht. Dazu wurden Untersuchungen an zwei halbtechnischen Versuchsanlagen durchgefuehrt, von denen eine ohne und die andere mit P-Faellung betrieben wurde. Der Ueberschussschlamm beider Anlagen wurde mit Hilfe der anaerob-mesophilen Stabilisierung anschliessend getrennt ausgefault. Variiert wurden die relativen Faellmittelmenge ({beta}=0,7 bis 2), die P-Konzentration im Zulauf (15 bis 20 mg/l P{sub ges}) und das Schlammalter (4 bis 8 Tage). Die Verwendung von AVR zur Phosphatfaellung fuehrte zu einem zusaetzlichen...

  19. ArcGeomorphometry: A toolbox for geomorphometric characterisation of DEMs in the ArcGIS environment

    Science.gov (United States)

    Rigol-Sanchez, Juan P.; Stuart, Neil; Pulido-Bosch, Antonio

    2015-12-01

    A software tool is described for the extraction of geomorphometric land surface variables and features from Digital Elevation Models (DEMs). The ArcGeomorphometry Toolbox consists of a series of Python/Numpy processing functions, presented through an easy-to-use graphical menu for the widely used ArcGIS package. Although many GIS provide some operations for analysing DEMs, the methods are often only partially implemented and can be difficult to find and used effectively. Since the results of automated characterisation of landscapes from DEMs are influenced by the extent being considered, the resolution of the source DEM and the size of the kernel (analysis window) used for processing, we have developed a tool to allow GIS users to flexibly apply several multi-scale analysis methods to parameterise and classify a DEM into discrete land surface units. Users can control the threshold values for land surface classifications. The size of the processing kernel can be used to identify land surface features across a range of landscape scales. The pattern of land surface units from each attempt at classification is displayed immediately and can then be processed in the GIS alongside additional data that can assist with a visual assessment and comparison of a series of results. The functionality of the ArcGeomorphometry toolbox is described using an example DEM.

  20. COMPARISON AND CO-REGISTRATION OF DEMS GENERATED FROM HiRISE AND CTX IMAGES

    Directory of Open Access Journals (Sweden)

    Y. Wang

    2016-06-01

    Full Text Available Images from two sensors, the High-Resolution Imaging Science Experiment (HiRISE and the Context Camera (CTX, both on-board the Mars Reconnaissance Orbiter (MRO, were used to generate high-quality DEMs (Digital Elevation Models of the Martian surface. However, there were discrepancies between the DEMs generated from the images acquired by these two sensors due to various reasons, such as variations in boresight alignment between the two sensors during the flight in the complex environment. This paper presents a systematic investigation of the discrepancies between the DEMs generated from the HiRISE and CTX images. A combined adjustment algorithm is presented for the co-registration of HiRISE and CTX DEMs. Experimental analysis was carried out using the HiRISE and CTX images collected at the Mars Rover landing site and several other typical regions. The results indicated that there were systematic offsets between the HiRISE and CTX DEMs in the longitude and latitude directions. However, the offset in the altitude was less obvious. After combined adjustment, the offsets were eliminated and the HiRISE and CTX DEMs were co-registered to each other. The presented research is of significance for the synergistic use of HiRISE and CTX images for precision Mars topographic mapping.

  1. TanDEM-X the Earth surface observation project from space level - basis and mission status

    Directory of Open Access Journals (Sweden)

    Jerzy Wiśniowski

    2015-03-01

    Full Text Available TanDEM-X is DLR (Deutsches Zentrum für Luft- und Raumfahrt the Earth surface observation project using high-resolution SAR interferometry. It opens a new era in space borne radar remote sensing. The system is based on two satellites: TerraSAR-X (TSX and TanDEM-X (TDX flying on the very close, strictly controlled orbits. This paper gives an overview of the radar technology and overview of the TanDEM-X mission concept which is based on several innovative technologies. The primary objective of the mission is to deliver a global digital elevation model (DEM with an unprecedented accuracy, which is equal to or surpass the HRTI-3 specifications (12 m posting, relative height accuracy ±2 m for slope < 20% and ±4 m for slope > 20% [8]. Beyond that, TanDEM-X provides a highly reconfigurable platform for the demonstration of new radar imaging techniques and applications.[b]Keywords[/b]: remote sensing, Bistatic SAR, digital elevation model (DEM, Helix formation, SAR interferomery, HRTI-3, synchronization

  2. Development and Applications of Dome A-DEM in Antarctic Ice Sheet

    Institute of Scientific and Technical Information of China (English)

    LIU Jiying; WEN Jiahong; WANG Yafeng; WANG Weili; Beata M CATHSO; Kenneth C JEZEK

    2007-01-01

    Dome A, the highest dome of East Antarctic Ice Sheet, is being an area focused by international Antarctic community after Chinese Antarctic Expedition finally reached there in 2005, and with the ongoing International Polar Year (IPY) during August 2007. In this paper two data processing methods are used together to generate two 100-m cell size digital elevation models (DEMs) of the Dome A region (Dome A-DEM) by using Cokriging method to interpolate the ICESat GLAS data, with Ihde-DEM as a constraint. It provides fundamental data to glaciological and geophysical investigation in this area. The Dome A-DEM was applied to determining the ice-sheet surface elevations and coordinates of the south and north summits, defining boundaries of basins and ice flowlines, deducing subglacial topography, and mapping surface slope and aspect in Dome A region. The DEM shows there are two (north and south) summits in Dome A region. The coordinate and the surface elevation of the highest point (the north summit) are 80°21'29.86"S, 77°21'50.29"E and 4092.71±1.43m, respectively. The ice thickness and sub-ice bedrock elevation at north summit are 2420m and 1672m, respectively. Dome A region contains four drainage basins that meet together near the south summit. Ice flowlines, slope and aspect in detail are also derived using the DEM.

  3. Influence of solar radiation absorbed by the human body on the thermal sensation of building occupants; Einfluss der vom menschlichen Koerper absorbierten Solarstrahlung fuer das Waermeempfinden in Gebaeuden

    Energy Technology Data Exchange (ETDEWEB)

    Otto, Frank [Zentrum fuer Umweltbewusstes Bauen e. V. (ZUB), Verein an der Universitaet Kassel (Germany)

    2009-02-15

    One of the key aspects of sustainable building is the well-being of occupants, which is greatly influenced by indoor climate conditions. Thermal comfort is a vital ingredient of satisfaction with people's surroundings. It is to be expected that solar radiation will have a favourable influence on indoor social areas particularly in the winter months when radiation is predominantly diffuse. In contrast, direct exposure to sunshine in summer or on very sunny days in winter can quickly make people feel uncomfortable near windows and this must be counteracted by appropriate measures to protect them from the sun. The significance of solar radiation for the thermal sensation is illustrated on the basis of a further development of Fanger's approach by means of simulations. The main results are summarised in this article. (Abstract Copyright [2009], Wiley Periodicals, Inc.) [German] Das nachhaltige Bauen hat u. a. das Wohlbefinden des Menschen im Blick, das wesentlich vom Raumklima beeinflusst wird. Von zentraler Bedeutung fuer ein hohes Mass an Zufriedenheit mit der Umgebung ist thermische Behaglichkeit. Es ist zu erwarten, dass die Solarstrahlung vor allen Dingen in den Wintermonaten aufgrund der dominierenden diffusen Strahlung einen guenstigen Einfluss auf Aufenthaltsraeume hat. Hingegen kann eine direkte Besonnung im Sommer oder an strahlungsreichen Wintertagen in Fensternaehe schnell zu unbehaglichen Zustaenden fuehren, denen durch entsprechende Sonnenschutzmassnahmen entgegengewirkt werden muss. Die Bedeutung der Solarstrahlung fuer das Waermeempfinden wird auf der Grundlage einer Weiterentwicklung des Fanger schen Ansatzes anhand von Simulationsrechnungen aufgezeigt. Im Beitrag werden die wesentlichen Ergebnisse zusammengefasst (copyright 2009 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (Abstract Copyright [2009], Wiley Periodicals, Inc.)

  4. Oxygen segregation and its impact on the absorption of hydrogen in vanadium; Einfluss der Sauerstoffsegregation auf die Absorption von Wasserstoff in Vanadium

    Energy Technology Data Exchange (ETDEWEB)

    Paulus, H.; Lammers, M. [Inst. fuer Technologie- und Wissenstransfer, Soest (Germany); Mueller, K.H. [Inst. fuer Technologie- und Wissenstransfer, Soest (Germany)]|[Paderborn Univ. (Gesamthochschule), Soest (Germany). Fachbereich 16 - Elektrische Energietechnik; Kiss, G.; Kemeny, Z. [Technical Univ. Budapest (Hungary)

    1998-12-31

    The impact of the dissolved oxygen on the hydrogen absorption in vanadium was analysed with an UHV apparatus. The vanadium specimen with an oxygen content of 230 ppm was treated by a variety of heat treatments. The depth distributions of the induced concentrations of segregated oxygen in the specimen were analysed by SIMS. It was found that the amount of segregated oxygen increases with rising final temperature and tempering period. In a further experiment, the specimen was exposed after each segregation process to a H{sub 2}-pressure of 2.2 x 10{sup -4} Pa for a period of 1800 sec. The hydrogen amounts absorbed in the specimen were determined by thermal desorption mass spectrometry (TDMS). It was found that segregation of oxygen close to the surface of the specimen likewise hampers the absorption of hydrogen. (orig./CB) [Deutsch] Der Einfluss des im Volumen geloesten Sauerstoffs auf die Wasserstoff-Absorption in Vanadium wurde in einer UHV-Apparatur untersucht. Zunaechst wurde die V-Probe mit einem Sauerstoffgehalt von 230 ppm unterschiedlichen thermischen Behandlungen ausgesetzt. Die sich einstellenden Konzentrationstiefenverteilungen des an der Oberflaeche segregierten Sauerstoffs wurden anschliessend mit SIMS untersucht. Dabei nimmt die Menge des segregierten Sauerstoffs mit der Hoehe der Endtemperatur sowie der Temperzeit zu. In einem weiteren Experiment wurde die Probe nach jeder Segregationsprozedur fuer eine Zeit von 1800 sec einem H{sub 2}-Druck von 2.2 x 10{sup -4} Pa ausgesetzt. Die Mengen des dabei aufgenommenen Wasserstoffs wurden mit Hilfe der thermischen Desorptions-Massenspektrometrie TDMS bestimmt. Dabei zeigt sich, dass auch die Segregation von Sauerstoff im oberflaechennahen Bereich die Wasserstoffaufnahme in Vanadium behindert. (orig.)

  5. Influence of enhanced biological phosphate removal on feedback of phosphorus from sludge treatment; Einfluss der erhoehten biologischen Phosphorelimination auf die Phosphorrueckbelastung aus der Schlammbehandlung

    Energy Technology Data Exchange (ETDEWEB)

    Jardin, N. [Inst. WAR, TH Darmstadt (Germany); Poepel, H.J. [Inst. WAR, TH Darmstadt (Germany)

    1995-06-01

    Phosphate release and phosphate fixation during sludge treatment of excess sludge was investigated with a pilot plant for enhanced biological phosphorus removal. The major part of the eliminated phosphorus in the pilot plant was due to the storage of polyphosphate in the excess sludge and was accompanied by an uptake of magnesium and potassium. Using separate thickening systems only a small P-feedback was observed, whereas with gravity thickeners a part of the polyphosphate was hydrolysed and phosphate was released into solution. Due to only a small transfer of the released phosphate from the sludge layer into the supernatant, the P-feedback was relatively low. As a result of a complete polyphosphate hydrolysis in stabilising systems, phosphate is released, but only a small part of the released phosphate remains in solution whereas the major fraction of the released phosphate was fixed by physico-chemical fixation mechanisms. (orig.) [Deutsch] Es wird ueber systematische Untersuchungen im halbtechnischen Massstab zum Einfluss der erhoehten biologischen Phosphorelimination auf die Phosphatrueckloesung und Phosphatrueckbelastung bei der Schlammbehandlung berichtet. Die durchgefuehrten Untersuchungen zeigten, dass der groesste Teil des im erhoehten Umfang gespeicherten Phosphors auf die Einlagerung von Polyphosphat zurueckzufuehren ist, wobei gleichzeitig auch Kalium- und Magnesiumionen aufgenommen werden. Die maschinellen Verfahren zur getrennten Ueberschussschlammeindickung verursachen nur eine geringe P-Rueckbelastung, waehrend bei der Schwerkrafteindickung das Polyphosphat teilweise hydrolysiert und als Phosphat rueckgeloest wird. Allerdings wurde nur ein geringer Transfer in den Ueberstand beobachtet, so dass die P-Rueckbelastung auch bei der Schwerkrafteindickung vergleichsweise gering war. Bei der Faulung und der aerob-thermophilen Stabilisierung wird das Polyphosphat vollstaendig hydrolisiert, aber nur ein kleiner Teil des freigesetzten Phosphats verbleibt in

  6. Numerical investigations on the influence of wind shear and turbulence on aircraft trailing vortices; Numerische Untersuchungen zum Einfluss von Windscherung und Turbulenz auf Flugzeugwirbelschleppen

    Energy Technology Data Exchange (ETDEWEB)

    Hofbauer, T.

    2003-07-01

    In several aspects, the behaviour of aircraft wake vortices under situations of vertical wind shear is significantly different from non-shear scenarios and its operational real-time forcast is challenging. By means of numerical investigations of idealized scenarios, the influence of wind shear on the lateral and vertical transport of vortices is analysed both, phenomenologically as well as in the scope of a sensitivity study. The results allow for the verification of controversial views and the benchmark of modelling approaches. Case studies of turbulent shear flows focus on the persistence of vortices. A detailed analysis of the flow fields evidence that unequal vortex decay rates can be attributed to the asymmetric distribution of secondary vorticity structures. The results moreover suggest that extended vortex lifespans can be expected under situations of wind shear. The unusual vortex behaviour observed by means of a LIDAR measurement is reproduced by realistic simulations and permits to reveal potential causes. (orig.) [German] Das Wirbelschleppenverhalten unterscheidet sich in Situationen vertikaler Windscherung in mehrfacher Hinsicht signifikant von scherungsfreien Szenarien und stellt eine besondere Herausforderung fuer eine operationelle Echtzeitvorhersage dar. Mittels numerischer Untersuchungen idealisierter Szenarien wird zunaechst der Einfluss von Windscherung auf den lateralen und vertikalen Wirbeltransport sowohl phaenomenologisch als auch quantitativ im Rahmen einer Sensitivitaetsstudie analysiert. Anhand der gewonnenen Ergebnisse werden auseinandergehende Erklaerungsansaetze geprueft und Modellierungsansaetze bewertet. Fallstudien turbulenter Scherstroemungen zur Wirbelpersistenz stellen einen weiteren Schwerpunkt dieser Arbeit dar. Durch die ausfuehrliche Analyse der Stroemungsfelder wird der Nachweis erbracht, dass sich unterschiedliche Zerfallsraten der Wirbel auf die asymmetrische Verteilung von sekundaeren Vorticity-Strukturen zurueckfuehren

  7. Zum Einfluss optimierter Lichtstärkeverteilungskörper auf die Erkennbarkeit bei niedrigen Beleuchtungsniveaus in der Straßenbeleuchtung

    OpenAIRE

    Schade, Sebastian

    2015-01-01

    Seit der Einführung der Straßenbeleuchtung besteht ein Zielkonflikt zwischen dem Bestreben geringer Anlagenbetriebskosten und der Forderung nach angemessen hoher Beleuchtungsqualität zur Wahrung der Verkehrssicherheit. Mit den steigenden Energiekosten nimmt der Druck, Beleuchtungsanlagen auf ein Mindestbeleuchtungsniveau hin zu dimensionieren, weiter zu. Aus lichttechnischer Sicht kann dieser Konflikt durch eine optimal dimensionierte Verteilung des Lichts auf die Verkehrsfläche entschärft we...

  8. 高精度CMOS DEM-CCⅡ放大器%High-Precision CMOS DEM-CC Ⅱ Amplifier

    Institute of Scientific and Technical Information of China (English)

    张雷; 成立; 周洋; 张静; 倪雪梅; 王振宇

    2009-01-01

    采用动态元件匹配二代电流传输器(DEM-CCⅡ)技术,设计了一种0.35 μm标准工艺的高精度CMOS放大器.通过比较传统的CMOS运放可知,所设计的CMOS放大器既增大了输出摆幅又减小了输出阻抗,且有效地限制了有限的运放增益对电路性能的影响.仿真实验结果表明,该CMOS放大器增益误差比传统运放的增益误差小38~50倍,精度等级明显提高,因而特别适用于各类检测和信号调理放大器的设计中.%CMOS amplifiers with high-precision was designed in a standard 0.35 μm CMOS process by properly applying dynamic element matching to a second generation current conveyor. Compared with traditional CMOS circuits, the proposed approach alleviates the tradeoff between output swing and output resistance and is more robust against the finite operational amplifier gain. The simulation results show that the gain error is reduced 38~50 times than the gain error of operational amplifiers, and the precision is improved, it is very suitable for the design of various detections and signal conditioning amplifiers.

  9. Dense Fe-Rich Ejecta in Supernova Remnants DEM L238 and DEM L249: A New Class of Type Ia Supernova?

    CERN Document Server

    Borkowski, K J; Reynolds, S P

    2006-01-01

    We present observations of two LMC supernova remnants (SNRs), DEM L238 and DEM L249, with the Chandra and XMM-Newton X-ray satellites. Bright central emission, surrounded by a faint shell, is present in both remnants. The central emission has an entirely thermal spectrum dominated by strong Fe L-shell lines, with the deduced Fe abundance in excess of solar and not consistent with the LMC abundance. This Fe overabundance leads to the conclusion that DEM L238 and DEM L249 are remnants of thermonuclear (Type Ia) explosions. The shell emission originates in gas swept up and heated by the blast wave. A standard Sedov analysis implies about 50 solar masses in both swept-up shells, SNR ages between 10,000 and 15,000 yr, low (< 0.05 cm^-3) preshock densities, and subluminous explosions with energies of 3x10^50 ergs. The central Fe-rich supernova ejecta are close to collisional ionization equilibrium. Their presence is unexpected, because standard Type Ia SNR models predict faint ejecta emission with short ionizati...

  10. SHAPE AND ALBEDO FROM SHADING (SAfS FOR PIXEL-LEVEL DEM GENERATION FROM MONOCULAR IMAGES CONSTRAINED BY LOW-RESOLUTION DEM

    Directory of Open Access Journals (Sweden)

    B. Wu

    2016-06-01

    Full Text Available Lunar topographic information, e.g., lunar DEM (Digital Elevation Model, is very important for lunar exploration missions and scientific research. Lunar DEMs are typically generated from photogrammetric image processing or laser altimetry, of which photogrammetric methods require multiple stereo images of an area. DEMs generated from these methods are usually achieved by various interpolation techniques, leading to interpolation artifacts in the resulting DEM. On the other hand, photometric shape reconstruction, e.g., SfS (Shape from Shading, extensively studied in the field of Computer Vision has been introduced to pixel-level resolution DEM refinement. SfS methods have the ability to reconstruct pixel-wise terrain details that explain a given image of the terrain. If the terrain and its corresponding pixel-wise albedo were to be estimated simultaneously, this is a SAfS (Shape and Albedo from Shading problem and it will be under-determined without additional information. Previous works show strong statistical regularities in albedo of natural objects, and this is even more logically valid in the case of lunar surface due to its lower surface albedo complexity than the Earth. In this paper we suggest a method that refines a lower-resolution DEM to pixel-level resolution given a monocular image of the coverage with known light source, at the same time we also estimate the corresponding pixel-wise albedo map. We regulate the behaviour of albedo and shape such that the optimized terrain and albedo are the likely solutions that explain the corresponding image. The parameters in the approach are optimized through a kernel-based relaxation framework to gain computational advantages. In this research we experimentally employ the Lunar-Lambertian model for reflectance modelling; the framework of the algorithm is expected to be independent of a specific reflectance model. Experiments are carried out using the monocular images from Lunar Reconnaissance

  11. Shape and Albedo from Shading (SAfS) for Pixel-Level dem Generation from Monocular Images Constrained by Low-Resolution dem

    Science.gov (United States)

    Wu, Bo; Chung Liu, Wai; Grumpe, Arne; Wöhler, Christian

    2016-06-01

    Lunar topographic information, e.g., lunar DEM (Digital Elevation Model), is very important for lunar exploration missions and scientific research. Lunar DEMs are typically generated from photogrammetric image processing or laser altimetry, of which photogrammetric methods require multiple stereo images of an area. DEMs generated from these methods are usually achieved by various interpolation techniques, leading to interpolation artifacts in the resulting DEM. On the other hand, photometric shape reconstruction, e.g., SfS (Shape from Shading), extensively studied in the field of Computer Vision has been introduced to pixel-level resolution DEM refinement. SfS methods have the ability to reconstruct pixel-wise terrain details that explain a given image of the terrain. If the terrain and its corresponding pixel-wise albedo were to be estimated simultaneously, this is a SAfS (Shape and Albedo from Shading) problem and it will be under-determined without additional information. Previous works show strong statistical regularities in albedo of natural objects, and this is even more logically valid in the case of lunar surface due to its lower surface albedo complexity than the Earth. In this paper we suggest a method that refines a lower-resolution DEM to pixel-level resolution given a monocular image of the coverage with known light source, at the same time we also estimate the corresponding pixel-wise albedo map. We regulate the behaviour of albedo and shape such that the optimized terrain and albedo are the likely solutions that explain the corresponding image. The parameters in the approach are optimized through a kernel-based relaxation framework to gain computational advantages. In this research we experimentally employ the Lunar-Lambertian model for reflectance modelling; the framework of the algorithm is expected to be independent of a specific reflectance model. Experiments are carried out using the monocular images from Lunar Reconnaissance Orbiter (LRO

  12. Bathymetric survey of water reservoirs in north-eastern Brazil based on TanDEM-X satellite data.

    Science.gov (United States)

    Zhang, Shuping; Foerster, Saskia; Medeiros, Pedro; de Araújo, José Carlos; Motagh, Mahdi; Waske, Bjoern

    2016-11-15

    Water scarcity in the dry season is a vital problem in dryland regions such as northeastern Brazil. Water supplies in these areas often come from numerous reservoirs of various sizes. However, inventory data for these reservoirs is often limited due to the expense and time required for their acquisition via field surveys, particularly in remote areas. Remote sensing techniques provide a valuable alternative to conventional reservoir bathymetric surveys for water resource management. In this study single pass TanDEM-X data acquired in bistatic mode were used to generate digital elevation models (DEMs) in the Madalena catchment, northeastern Brazil. Validation with differential global positioning system (DGPS) data from field measurements indicated an absolute elevation accuracy of approximately 1m for the TanDEM-X derived DEMs (TDX DEMs). The DEMs derived from TanDEM-X data acquired at low water levels show significant advantages over bathymetric maps derived from field survey, particularly with regard to coverage, evenly distributed measurements and replication of reservoir shape. Furthermore, by mapping the dry reservoir bottoms with TanDEM-X data, TDX DEMs are free of emergent and submerged macrophytes, independent of water depth (e.g. >10m), water quality and even weather conditions. Thus, the method is superior to other existing bathymetric mapping approaches, particularly for inland water bodies. The proposed approach relies on (nearly) dry reservoir conditions at times of image acquisition and is thus restricted to areas that show considerable water levels variations. However, comparisons between TDX DEM and the bathymetric map derived from field surveys show that the amount of water retained during the dry phase has only marginal impact on the total water volume derivation from TDX DEM. Overall, DEMs generated from bistatic TanDEM-X data acquired in low water periods constitute a useful and efficient data source for deriving reservoir bathymetry and show

  13. Delivery of parameterization schemes for the determination of the regional evapotranspiration of different land surfaces. Final report; Bereitstellung von Parameterisierungsverfahren zur Bestimmung der regionalen Verdunstung verschiedener Landoberflaechen. Abschlussbericht 1997

    Energy Technology Data Exchange (ETDEWEB)

    Haenel, H.D.; Loepmeier, F.J.

    1998-03-01

    The task was the delivery of parameterization schemes for the calculation of the regional evapotranspiration of different land surfaces. The main weight was on the discussion of existing approaches and on the development of new ones for the calculation of evapotranspiration. After consideration of different concepts the well-known Penman-Monteith equation proved to the optimal basis of calculation. The surface resistance, respectively the related bulk-stomata resistance, is an important part of the resistance pattern (analogous to Ohm`s law) on which the Penman-Monteith equation is based. Under consideration of the dependence of these resistances of the spatial scale (leaf, canopy) as well as of the time scale (hour, day) possibilities for their estimation were discussed. An important step to determine the surface resistances from literature data of vegetation evapotranspiration was the development of a converting scheme of Haude`s factors to surface resistances. For bare soil an approach was developed which allows approximately to give a new interpretation to surface resistances from evapotranspiration courses, described in literature as proportional to the square root of time. (orig.) [Deutsch] Die Aufgabenstellung bestand in der Bereitstellung von Parametrisierungsverfahren zur Bestimmung der regionalen Verdunstung verschiedener Landoberflaechen. Dabei lag das Schwergewicht auf der Diskussion bereits bestehender und der Entwicklung neuer Ansaetze zur Berechnung der Verdunstung. Nach der Betrachtung unterschiedlicher Konzepte erwies sich die bekannte Penman-Monteith-Gleichung als optimale Berechnungsgrundlage. Ein wesentlicher Bestandteil des der Penman-Monteith-Gleichung zugrundeliegenden Widerstandsschemas (Analogie zum Ohmschen Gesetz) ist der Oberflaechenwiderstand bzw. der damit verwandte Bulk-Stomatawiderstand. Unter Beruecksichtigung der Abhaengigkeit dieser Widerstaende sowohl von der raeumlichen Skala (Blatt/Bestand) als auch von der zeitlichen Skala

  14. Metabolic dose-effect relationships of different Pt compounds on growing, pregnant, and lactating rats; Metabolische Dosis-Wirkungsbeziehungen verschiedener Pt-Verbindungen bei wachsenden, graviden und laktierenden Ratten (VPT 04)

    Energy Technology Data Exchange (ETDEWEB)

    Eder, K.; Kirchgessner, M. [Technische Univ. Muenchen, Freising (Germany). Lehrstuhl fuer Tierernaehrung

    1997-12-31

    The fact that humans can take up platinum via the food chain calls for an investigation of the effects of platinum ingestion on the organism. For this purpose a study was carried out on the dose-effect relationships of various platinum compounds using the rat as a model. To take due account of different physiological stages the study included growing, pregnant, and lactating rats. According to present knowledge platinum is primarily emitted in its elemental form by the catalytic converter, i.e. with the formal oxidation number zero, and to a lesser degree in ionic form. Beside elemental platinum the study therefore also involved exposure to PtCl{sub 2} and PtCl{sub 4}. Furthermore, to do justice to the fact that humans and animals take up platinum not only from its primary source but also from plants in the food chain, platinum was also administered as a Pt-II-phytochelatin complex previously isolated from Pt-contaminated material. Study criteria were chosen with a view to obtaining a general indication of potential toxic effects and included parameters such as the live weight curve, haematological status, and platinum accumulation in the body or in specific organs. Of particular interest in pregnant and lactating rats were platinum levels in foetuses and milk. [Deutsch] Ueber die Nahrungskette ist eine alimentaere Aufnahme von Platin durch den Menschen moeglich und erfordert, die Auswirkungen der ingestiven Platinzufuhr auf den Organismus zu untersuchen. Deshalb wurden am Modelltier Ratte Studien zur Dosis-Wirkungsbeziehung verschiedener Platinverbindungen durchgefuehrt. Um den verschiedenen physiologischen Stadien gerecht zu werden, wurden sowohl wachsende wie auch gravide und laktierende Ratten in die Studien einbezogen. Soweit bislang bekannt, wird Platin vorwiegend in der formalen Oxidationsstufe Null als elementares Platin, zu einem geringeren Anteil aber auch in ionischer Form aus der Katalysatoreinheit ausgetragen. Deshalb wurden in den vorliegenden

  15. Visualization and comparison of DEM-derived parameters. Application to volcanic areas

    Science.gov (United States)

    Favalli, Massimiliano; Fornaciai, Alessandro

    2017-08-01

    Digital Elevation Models (DEMs) are fruitfully used in volcanology as the topographic base for mapping and quantifying volcanic landforms. The increasing availability of free topographic data on the web, decreasing production costs for high-accuracy data and advances in computer technology, has triggered rapid growth of the number of DEM users in the volcanological community. DEMs are often visualized only as hill-shaded maps, and while this is among the major advantages in using them, the possibility of deriving a very large number of parameters from a single grid of elevation data makes DEMs a powerful tool for morphometric analysis. However, many of these parameters have almost the same informative content, and before starting to elaborate topographic data it is recommended to know a-priori what parameters best visualize the investigated landform, and therefore what is necessary and what is redundant. In this work, we review a number of analytical procedures used to parameterize and represent DEMs. A LIDAR-derived DEM matrix acquired over the Valle del Bove valley, on Mt. Etna, is used as test-case elevation data for deriving the parameters. We first review well known parameters such as hill-shading, slope and aspect, curvature, and roughness, before extending the review to some less common parameters such as Sky View Factor (SVF), openness, and Red Relief Image Maps (RRIM). For each parameter a description is given emphasizing how it can be used for identifying and delimiting specific volcanic elements. The analyzed surface parameters are then cross-compared in order to infer which of them is most uncorrelated, and the results are represented in the form of a correlation matrix. Finally, the reviewed DEM-derived parameters and the correlation matrix are used for analyzing the volcanic landforms of two case studies: Michoacán-Guanajuato volcanic field and a phonolitic lava flow at the Island of Tenerife.

  16. CFD-DEM simulations of current-induced dune formation and morphological evolution

    Science.gov (United States)

    Sun, Rui; Xiao, Heng

    2016-06-01

    Understanding the fundamental mechanisms of sediment transport, particularly those during the formation and evolution of bedforms, is of critical scientific importance and has engineering relevance. Traditional approaches of sediment transport simulations heavily rely on empirical models, which are not able to capture the physics-rich, regime-dependent behaviors of the process. With the increase of available computational resources in the past decade, CFD-DEM (computational fluid dynamics-discrete element method) has emerged as a viable high-fidelity method for the study of sediment transport. However, a comprehensive, quantitative study of the generation and migration of different sediment bed patterns using CFD-DEM is still lacking. In this work, current-induced sediment transport problems in a wide range of regimes are simulated, including 'flat bed in motion', 'small dune', 'vortex dune' and suspended transport. Simulations are performed by using SediFoam, an open-source, massively parallel CFD-DEM solver developed by the authors. This is a general-purpose solver for particle-laden flows tailed for particle transport problems. Validation tests are performed to demonstrate the capability of CFD-DEM in the full range of sediment transport regimes. Comparison of simulation results with experimental and numerical benchmark data demonstrates the merits of CFD-DEM approach. In addition, the improvements of the present simulations over existing studies using CFD-DEM are presented. The present solver gives more accurate prediction of sediment transport rate by properly accounting for the influence of particle volume fraction on the fluid flow. In summary, this work demonstrates that CFD-DEM is a promising particle-resolving approach for probing the physics of current-induced sediment transport.

  17. Effects of LiDAR Derived DEM Resolution on Hydrographic Feature Extraction

    Science.gov (United States)

    Yang, P.; Ames, D. P.; Glenn, N. F.; Anderson, D.

    2010-12-01

    This paper examines the effect of LiDAR-derived digital elevation model (DEM) resolution on digitally extracted stream networks with respect to known stream channel locations. Two study sites, Reynolds Creek Experimental Watershed (RCEW) and Dry Creek Experimental Watershed (DCEW), which represent terrain characteristics for lower and intermediate elevation mountainous watersheds in the Intermountain West, were selected as study areas for this research. DEMs reflecting bare earth ground were created from the LiDAR observations at a series of raster cell sizes (from 1 m to 60 m) using spatial interpolation techniques. The effect of DEM resolution on resulting hydrographic feature (specifically stream channel) derivation was studied. Stream length, watershed area, and sinuosity were explored at each of the raster cell sizes. Also, variation from known channel location as estimated by root mean square error (RMSE) between surveyed channel location and extracted channel was computed for each of the DEMs and extracted stream networks. As expected, the results indicate that the DEM based hydrographic extraction process provides more detailed hydrographic features at a finer resolution. RMSE between the known channel location and modeled locations generally increased with larger cell size DEM with a greater effect in the larger RCEW. Sensitivity analyses on sinuosity demonstrated that the resulting shape of streams obtained from LiDAR data matched best with the reference data at an intermediate cell size instead of highest resolution, which is at a range of cell size from 5 to 10 m likely due to original point spacing, terrain characteristics, and LiDAR noise influence. More importantly, the absolute sinuosity deviation displayed a smallest value at the cell size of 10 m in both experimental watersheds, which suggests that optimal cell size for LiDAR-derived DEMs used for hydrographic feature extraction is 10 m.

  18. Effect of DEM resolution on SWAT outputs of runoff, sediment and nutrients

    Directory of Open Access Journals (Sweden)

    S. Lin

    2010-07-01

    Full Text Available Digital Elevation Models (DEMs have been successfully used in a large range of environmental issues. Several methods such as digital contour interpolation and remote sensing have allowed the generation of DEMs, some of which are now freely available for almost the entire globe. The Soil and Water Assessment Tool (SWAT is a widely used semi-distributed model operating at the watershed level and has previously been shown to be very sensitive to the quality of the input topographic information. The objective of this study was to evaluate the impact of DEMs generated from different data sources, respectively DLG5m (local Digital Line Graph, 5 m interval, ASTER30m (1 arc-s ASTER Global DEM Version 1, approximately 30 m resolution, and SRTM90m (3 arc-s SRTM Version 4, approximately 90 m resolution, on SWAT predictions for runoff, sediment, total phosphor (TP and total nitrogen (TN. Eleven resolutions, from 5 m to 140 m, were considered in this study. Results indicate that the predictions of TPs and TNs decreased substantially with coarser resampled resolution. Slightly decreased trends could be found in the predicted sediments when DEMs were resampled to coarser resolutions. Predicted runoffs were not sensitive to resampled resolutions. The predicted outputs based on DLG5m were more sensitive to resampled resolutions than those based on ASTER30m and SRTM90m. At original resolutions, the predicted outputs based on ASTER30m and SRTM90m were similar, but the predicted TNs and TPs based on ASTER30m and SRTM90m were much lower than the one based on DLG5m. For the predicted TNs and TPs, which were substantially sensitive to DEM resolutions, the output accuracies of SWAT derived from ASTER30m and SRTM90m could be improved by down-scaled resampling, but they could not improve on finer DEM (DLG5m at the same resolution. This study helps GIS environmental model users to understand the sensitivities of SWAT to DEM resolution, and choose feasible DEM data for

  19. Comparison of mesh-based and particle-based CFD coupling with DEM

    CERN Document Server

    Markauskas, D; Sivanesapillai, R; Steeb, H

    2016-01-01

    A comparative study on mesh-based and particle-based computational fluid dynamics (CFD) coupling with a discrete element method (DEM) is presented. As the mesh-based CFD method a finite volume method (FVM) is used. A smoothed particle hydrodynamics (SPH) method represents particle-based CFD. An unresolved fluid model with locally averaged Navier-Stokes equations for the fluid is used. A newly developed model of boundary conditions for the SPH is described and the validation tests are performed. With the help of the performed comparative tests, the similarities and differences of particle movements in both DEM-FVM and DEM-SPH methods are discussed. Three test cases, namely a single particle sedimentation test, flow through a porous block and sedimentation of a porous block, are performed using DEM-FVM and DEM-SPH methods. The drag force acting onto the solid particles highly depends on the fluid fraction. To be able to compare both methods, the size of the cell in FVM is chosen to give the same fluid fraction ...

  20. An advanced distributed automated extraction of drainage network model on high-resolution DEM

    Science.gov (United States)

    Mao, Y.; Ye, A.; Xu, J.; Ma, F.; Deng, X.; Miao, C.; Gong, W.; Di, Z.

    2014-07-01

    A high-resolution and high-accuracy drainage network map is a prerequisite for simulating the water cycle in land surface hydrological models. The objective of this study was to develop a new automated extraction of drainage network model, which can get high-precision continuous drainage network on high-resolution DEM (Digital Elevation Model). The high-resolution DEM need too much computer resources to extract drainage network. The conventional GIS method often can not complete to calculate on high-resolution DEM of big basins, because the number of grids is too large. In order to decrease the computation time, an advanced distributed automated extraction of drainage network model (Adam) was proposed in the study. The Adam model has two features: (1) searching upward from outlet of basin instead of sink filling, (2) dividing sub-basins on low-resolution DEM, and then extracting drainage network on sub-basins of high-resolution DEM. The case study used elevation data of the Shuttle Radar Topography Mission (SRTM) at 3 arc-second resolution in Zhujiang River basin, China. The results show Adam model can dramatically reduce the computation time. The extracting drainage network was continuous and more accurate than HydroSHEDS (Hydrological data and maps based on Shuttle Elevation Derivatives at multiple Scales).

  1. Geomorphic change detection using historic maps and DEM differencing: The temporal dimension of geospatial analysis

    Science.gov (United States)

    James, L. Allan; Hodgson, Michael E.; Ghoshal, Subhajit; Latiolais, Mary Megison

    2012-01-01

    The ability to develop spatially distributed models of topographic change is presenting new capabilities in geomorphic research. High resolution maps of elevation change indicate locations, processes, and rates of geomorphic change, and provide a means of calibrating temporal simulation models. Methods of geomorphic change detection (GCD), based on gridded models, may be applied to a wide range of time periods by utilizing cartometric, remote sensing, or ground-based topographic survey data to measure volumetric change. Advantages and limitations of historical DEM reconstruction methods are reviewed with a focus on coupling them with subsequent DEMs to construct DEMs of difference (DoD), which can be created by subtracting one elevation model from another, to map erosion, deposition, and volumetric change. The period of DoD analysis can be extended to several decades if accurate historical DEMs can be generated by extracting topographic data from historical data and selecting areas where geomorphic change has been substantial. The challenge is to recognize and minimize uncertainties in data that are particularly elusive with early topographic data. This paper reviews potential sources of error in digitized topographic maps and DEMs. Although the paper is primarily a review of methods, three brief examples are presented at the end to demonstrate GCD using DoDs constructed from data extending over periods ranging from 70 to 90 years.

  2. Einfluss von hormonellen Kontrazeptiva auf das Größenwachstum und den Knochenbau von 12-14-jährigen Mädchen: Stellungnahme der DGGEF

    Directory of Open Access Journals (Sweden)

    Rabe T

    2009-01-01

    Full Text Available Für die normale Funktion und Stabilität des Knochens ist der regelrechte Aufbau der Knochenmasse und -struktur während der Wachstumsphase in der Jugend bis zum 25. Lebensjahr erforderlich. Orale hormonale Kontrazeptiva, die aus therapeutischen Gründen bzw. zur Kontrazeption von 12–14-jährigen Mädchen (insbesondere auch Sportlerinnen eingenommen werden, sollen weder den Knochenaufbau noch das Größenwachstum beeinflussen. Im Rahmen dieser Arbeit werden die Steuerung des Größenwachstums, die Bedeutung der Körpergröße für das einzelne Mädchen, Parameter zur Beurteilung der Körpergröße in einer Wachstumsprognose, die Hormonbehandlung bei Großwuchs, der Einsatz hormonaler Kontrazeptiva bei den 12–14- jährigen Mädchen sowie der Einfluss der Steroidhormone auf den Knochen zusammengefasst. Bei Jugendlichen ist nach der Etablierung des menstruellen Zyklus durch die Einnahme einer Pille nicht mit einer nachteiligen Wirkung auf das Größenwachstum zu rechnen. Ob durch die Einnahme der Pille bei Jugendlichen die maximale Peak-Bone-Mass eines Kontrollkollektivs ohne Pille erreicht wird, muss weiter untersucht werden. Hierbei sind insbesondere die Lebensumstände (z. B. bekannte genetische Disposition, Ernährungszustände zu berücksichtigen. Der möglicherweise geringe negative Effekt der Pille bei Jugendlichen auf die Peak-Bone-Mass muss im Rahmen der üblichen Risiko-Nutzen- Analyse bewertet werden. Hierbei überwiegt eindeutig der Nutzen der Pille, zumal nicht bewiesen ist, wie die Peak-Bone-Mass durch die unterschiedlichen Kontrazeptiva beeinflusst wird und wenn dies der Fall sein sollte, ob diese geringere Peak-Bone-Mass mit einem erhöhten Frakturrisiko in Zusammenhang steht. Die Anwendung von Depotgestagenen (z. B. Dreimonatsspritze bei Jugendlichen wird nicht empfohlen, da möglicherweise die Knochendichte und das Frakturrisiko beeinflusst werden könnten. Weiterhin ist bei jungen Sportlerinnen eine gesunde Ernährung für den

  3. Assessing indoor low velocity measurements. Pt. 1: Effect of measuring method on quantifying room air flow - comparison LDA - thermal anemometers; Messtechnische Erfassung characteristischer Kenngroessen von Raumluftstroemungen. T. 1: Einfluss der Messmethode bei der Bewertung von Raumluftstroemungen - Vergleich LDA - thermische Anemometer

    Energy Technology Data Exchange (ETDEWEB)

    Sefker, T.; Wolters, T. [Gebr. Trox GmbH, Neukirchen-Vluyn (Germany)

    2004-03-01

    Within the scope of an EU research project, Thermal Anemometers (TA) from different manufacturers were compared by means of a 'Laser Doppler Anemometer' (LDA) under model room conditions. Comparisons were carried out with different kinds of aerodynamic room flows, air change rates and heat loads. This article presents the measuring principle of thermal and 'Laser Doppler Anemometers', it demonstrates the measurements in the scale 1:1, it also demonstrates how the measured air velocities for the estimation of the aerodynamic room flows by means of statistical methods are developed and it presents the results of these measurements. (orig.) [German] Im Rahmen eines EU-Forschungsprojekts wurden Thermische Anemometer (TA) verschiedener Hersteller unter Modellraumbedingungen mit einem Laser Doppler Anemometer (LDA) verglichen. Vergleiche wurden fuer verschiedene Raumstroemungsarten, Luftwechsel und Raumlasten durchgefuehrt. Dieser Beitrag stellt das Messprinzip von thermischen und Laser Doppler Anemometern vor, demonstriert die Messungen im Massstab 1:1, zeigt wie die gemessenen Luftgeschwindigkeiten zur Beurteilung der Raumstroemung mittels statistischen Methoden weiterverarbeitet wurden und praesentiert die Ergebnisse dieser Betrachtungen. (orig.)

  4. FEM × DEM: a new efficient multi-scale approach for geotechnical problems with strain localization

    Directory of Open Access Journals (Sweden)

    Nguyen Trung Kien

    2017-01-01

    Full Text Available The paper presents a multi-scale modeling of Boundary Value Problem (BVP approach involving cohesive-frictional granular materials in the FEM × DEM multi-scale framework. On the DEM side, a 3D model is defined based on the interactions of spherical particles. This DEM model is built through a numerical homogenization process applied to a Volume Element (VE. It is then paired with a Finite Element code. Using this numerical tool that combines two scales within the same framework, we conducted simulations of biaxial and pressuremeter tests on a cohesive-frictional granular medium. In these cases, it is known that strain localization does occur at the macroscopic level, but since FEMs suffer from severe mesh dependency as soon as shear band starts to develop, the second gradient regularization technique has been used. As a consequence, the objectivity of the computation with respect to mesh dependency is restored.

  5. Granular dynamics, contact mechanics and particle system simulations a DEM study

    CERN Document Server

    Thornton, Colin

    2015-01-01

    This book is devoted to the Discrete Element Method (DEM) technique, a discontinuum modelling approach that takes into account the fact that granular materials are composed of discrete particles which interact with each other at the microscale level. This numerical simulation technique can be used both for dispersed systems in which the particle-particle interactions are collisional and compact systems of particles with multiple enduring contacts. The book provides an extensive and detailed explanation of the theoretical background of DEM. Contact mechanics theories for elastic, elastic-plastic, adhesive elastic and adhesive elastic-plastic particle-particle interactions are presented. Other contact force models are also discussed, including corrections to some of these models as described in the literature, and important areas of further research are identified. A key issue in DEM simulations is whether or not a code can reliably simulate the simplest of systems, namely the single particle oblique impact wit...

  6. CFD-DEM Simulations of Current-Induced Dune Formation and Morphological Evolution

    CERN Document Server

    Sun, Rui

    2015-01-01

    Understanding the fundamental mechanisms of sediment transport, particularly those during the formation and evolution of bedforms, is of critical scientific importance and has engineering relevance. Traditional approaches of sediment transport simulations heavily rely on empirical models, which are not able to capture the physics-rich, regime-dependent behaviors of the process. With the increase of available computational resources in the past decade, CFD-DEM (computational fluid dynamics-discrete element method) has emerged as a viable high-fidelity method for the study of sediment transport. However, a comprehensive, quantitative study of the generation and migration of different sediment bed patterns using CFD-DEM is still lacking. In this work, current-induced sediment transport problems in a wide range of regimes are simulated, including 'flat bed in motion', `small dune', `vortex dune' and suspended transport. Simulations are performed by using SediFoam, an open-source, massively parallel CFD-DEM solver...

  7. Diagnostic of the temperature and differential emission measure (DEM based on Hinode/XRT data

    Directory of Open Access Journals (Sweden)

    P. Rudawy

    2008-10-01

    Full Text Available We discuss here various methodologies and an optimal strategy of the temperature and emission measure diagnostics based on Hinode X-Ray Telescope data. As an example of our results we present the determination of the temperature distribution of the X-rays emitting plasma using a filters ratio method and three various methods of the calculation of the differential emission measure (DEM. We have found that all these methods give results similar to the two filters ratio method. Additionally, all methods of the DEM calculation gave similar solutions. We can state that the majority of the pairs of the Hinode filters allows one to derive the temperature and emission measure in the isothermal plasma approximation using standard diagnostics based on the two filters ratio method. In cases of strong flares one can also expect good conformity of the results obtained using a Withbroe – Sylwester, genetic algorithm and least-squares methods of the DEM evaluation.

  8. Diálise - demência: estudo eletrencefalográfico de um caso

    Directory of Open Access Journals (Sweden)

    Duilton de Paola

    1980-09-01

    Full Text Available Relato de um caso de insuficiência renal crônica, mantido em hemodiálise por vários anos, desenvolvendo demência e alterações eletrencefalográficas típicas da síndrome diálise-demência. O eletrencefalograma apresentava paroxismos de ondas "sharp" e lentas difusas, elevado potencial os quais desapareceram com o tratamento, permanecendo o traçado apenas irregular. Houve melhora também da demência. Na tentativa de retirar o diazepínico, houve recrudescência dos sintomas. São comentados os aspectos clínicos e eletrencefalográficos da síndrome.

  9. DEM investigation of weathered rocks using a novel bond contact model

    Institute of Scientific and Technical Information of China (English)

    Zhenming Shi; Tao Jiang; Mingjing Jiang; Fang Liu; Ning Zhang

    2015-01-01

    The distinct element method (DEM) incorporated with a novel bond contact model was applied in this paper to shed light on the microscopic physical origin of macroscopic behaviors of weathered rock, and to achieve the changing laws of microscopic parameters from observed decaying properties of rocks during weathering. The changing laws of macroscopic mechanical properties of typical rocks were summarized based on the existing research achievements. Parametric simulations were then conducted to analyze the relationships between macroscopic and microscopic parameters, and to derive the changing laws of microscopic parameters for the DEM model. Equipped with the microscopic weathering laws, a series of DEM simulations of basic laboratory tests on weathered rock samples was performed in comparison with analytical solutions. The results reveal that the relationships between macroscopic and microscopic parameters of rocks against the weathering period can be successfully attained by para-metric simulations. In addition, weathering has a significant impact on both stressestrain relationship and failure pattern of rocks.

  10. Laser altimetry data of Chang’E-1 and the global lunar DEM model

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The Laser AltiMeter (LAM), as one of the main payloads of Chang’E-1 probe, is used to measure the topography of the lunar surface. It performed the first measurement at 02:22 on November 28th, 2007. Up to December 4th 2008, the total number of measurements was approximately 9.12 million, covering the whole surface of the Moon. Using the LAM data, we constructed a global lunar Digtal Elevation Model (DEM) with 3 km spatial resolution. The model shows pronounced morphological characteristics, legible and vivid details of the lunar surface. The plane positioning accuracy of the DEM is 445 m (1σ), and the vertical accuracy is 60 m (1σ). From this DEM model, we measured the full range of the altitude difference on the lunar sur-face, which is about 19.807 km. The highest point is 10.629 km high, on a peak between crater Korolev and crater Dirichlet-Jackson at (158.656°W, 5.441°N) and the lowest point is -9.178 km in height, inside crater Antoniadi (172.413°W, 70.368°S) in the South Pole-Aitken Basin. By comparison, the DEM model of Chang’E-1 is better than the USA ULCN2005 in accuracy and resolution and is probably identical to the DEM of Japan SELENE, but the DEM of Chang’E-1 reveals a new lowest point, clearly lower than that of SELENE.

  11. A framework for global terrain classification using 250-m DEMs to predict geohazards

    Science.gov (United States)

    Iwahashi, J.; Matsuoka, M.; Yong, A.

    2016-12-01

    Geomorphology is key for identifying factors that control geohazards induced by landslides, liquefaction, and ground shaking. To systematically identify landforms that affect these hazards, Iwahashi and Pike (2007; IP07) introduced an automated terrain classification scheme using 1-km-scale Shuttle Radar Topography Mission (SRTM) digital elevation models (DEMs). The IP07 classes describe 16 categories of terrain types and were used as a proxy for predicting ground motion amplification (Yong et al., 2012; Seyhan et al., 2014; Stewart et al., 2014; Yong, 2016). These classes, however, were not sufficiently resolved because coarse-scaled SRTM DEMs were the basis for the categories (Yong, 2016). Thus, we develop a new framework consisting of more detailed polygonal global terrain classes to improve estimations of soil-type and material stiffness. We first prepare high resolution 250-m DEMs derived from the 2010 Global Multi-resolution Terrain Elevation Data (GMTED2010). As in IP07, we calculate three geometric signatures (slope, local convexity and surface texture) from the DEMs. We create additional polygons by using the same signatures and multi-resolution segmentation techniques on the GMTED2010. We consider two types of surface texture thresholds in different window sizes (3x3 and 13x13 pixels), in addition to slope and local convexity, to classify pixels within the DEM. Finally, we apply the k-means clustering and thresholding methods to the 250-m DEM and produce more detailed polygonal terrain classes. We compare the new terrain classification maps of Japan and California with geologic, aerial photography, and landslide distribution maps, and visually find good correspondence of key features. To predict ground motion amplification, we apply the Yong (2016) method for estimating VS30. The systematic classification of geomorphology has the potential to provide a better understanding of the susceptibility to geohazards, which is especially vital in populated areas.

  12. Im eller in dem? Et forsøg på en skalar forklaring

    OpenAIRE

    Mads Christiansen

    2008-01-01

    Das Thema dieser Arbeit ist die Verschmelzung von Präposition und bestimmtem Artikel im Deutschen. Vor dem Hintergrund der These, die Wahl zwischen der Verschmelzung und der analytischen Präposition-Artikel-Verbindung sei von den unterschiedlichen Referenz-eigenschaften der beiden Möglichkeiten abhängig, soll untersucht werden, ob sich der Gebrauch von im und in dem anhand eines skalaren Beschreibungsmodells erklären lässt. Grundlegend wird davon ausgegangen, dass die analytische Präposition-...

  13. Developmental Eye Movement (DEM Test Norms for Mandarin Chinese-Speaking Chinese Children.

    Directory of Open Access Journals (Sweden)

    Yachun Xie

    Full Text Available The Developmental Eye Movement (DEM test is commonly used as a clinical visual-verbal ocular motor assessment tool to screen and diagnose reading problems at the onset. No established norm exists for using the DEM test with Mandarin Chinese-speaking Chinese children. This study aims to establish the normative values of the DEM test for the Mandarin Chinese-speaking population in China; it also aims to compare the values with three other published norms for English-, Spanish-, and Cantonese-speaking Chinese children. A random stratified sampling method was used to recruit children from eight kindergartens and eight primary schools in the main urban and suburban areas of Nanjing. A total of 1,425 Mandarin Chinese-speaking children aged 5 to 12 years took the DEM test in Mandarin Chinese. A digital recorder was used to record the process. All of the subjects completed a symptomatology survey, and their DEM scores were determined by a trained tester. The scores were computed using the formula in the DEM manual, except that the "vertical scores" were adjusted by taking the vertical errors into consideration. The results were compared with the three other published norms. In our subjects, a general decrease with age was observed for the four eye movement indexes: vertical score, adjusted horizontal score, ratio, and total error. For both the vertical and adjusted horizontal scores, the Mandarin Chinese-speaking children completed the tests much more quickly than the norms for English- and Spanish-speaking children. However, the same group completed the test slightly more slowly than the norms for Cantonese-speaking children. The differences in the means were significant (P0.05; compared with Spanish-speaking children, the scores were statistically significant (P0.05. DEM norms may be affected by differences in language, cultural, and educational systems among various ethnicities. The norms of the DEM test are proposed for use with Mandarin Chinese

  14. Rechargable Lithium-Air Batteries: Investigation of Redox Mediators Using DEMS

    DEFF Research Database (Denmark)

    Christensen, Mathias Kjærgård; Storm, Mie Møller; Norby, Poul

    2016-01-01

    /charge cycling. Characterizing the gas content during charge using Differential Electrochemical Mass Spectroscopy (DEMS) allows for in-situ characterization of chemistry in the battery. Using our DEMS setup we have investigated different cathode materials for lithium-air batteries. A carbon black cathode...... material or electrolyte is being decomposed. This is also seen with Thermally reduced Graphene Oxide (TrGO). The graphene based cathode is interesting as it exhibits a high surface area which in turn increases capacity. Using the additive LiI, functioning as a redox mediator, the discharge curve remains...

  15. Developmental Eye Movement (DEM) Test Norms for Mandarin Chinese-Speaking Chinese Children.

    Science.gov (United States)

    Xie, Yachun; Shi, Chunmei; Tong, Meiling; Zhang, Min; Li, Tingting; Xu, Yaqin; Guo, Xirong; Hong, Qin; Chi, Xia

    2016-01-01

    The Developmental Eye Movement (DEM) test is commonly used as a clinical visual-verbal ocular motor assessment tool to screen and diagnose reading problems at the onset. No established norm exists for using the DEM test with Mandarin Chinese-speaking Chinese children. This study aims to establish the normative values of the DEM test for the Mandarin Chinese-speaking population in China; it also aims to compare the values with three other published norms for English-, Spanish-, and Cantonese-speaking Chinese children. A random stratified sampling method was used to recruit children from eight kindergartens and eight primary schools in the main urban and suburban areas of Nanjing. A total of 1,425 Mandarin Chinese-speaking children aged 5 to 12 years took the DEM test in Mandarin Chinese. A digital recorder was used to record the process. All of the subjects completed a symptomatology survey, and their DEM scores were determined by a trained tester. The scores were computed using the formula in the DEM manual, except that the "vertical scores" were adjusted by taking the vertical errors into consideration. The results were compared with the three other published norms. In our subjects, a general decrease with age was observed for the four eye movement indexes: vertical score, adjusted horizontal score, ratio, and total error. For both the vertical and adjusted horizontal scores, the Mandarin Chinese-speaking children completed the tests much more quickly than the norms for English- and Spanish-speaking children. However, the same group completed the test slightly more slowly than the norms for Cantonese-speaking children. The differences in the means were significant (Pspeaking Chinese children (Pspeaking children, only the vertical score of the 6-year-old group, the vertical-horizontal time ratio of the 8-year-old group and the errors of 9-year-old group had no significant difference (P>0.05); compared with Spanish-speaking children, the scores were statistically

  16. Adjustment System Design and Implementation of DEM Edge Examination%DEM 接边检查平差系统设计与实现

    Institute of Scientific and Technical Information of China (English)

    李孟军

    2014-01-01

    系统的开发与设计主要是解决生产的DEM文件中,相同X,Y点高程存在差异的问题。系统还可以检验DEM数据文件内部是否存在零高度点或无效值点,并且把检查结果以DAT文件(装有坐标的文本文件)的方式展现给操作者,为DEM生产的完整性做检验和平差工作。%The development of this system is mainly to solve the production and design of the DEM file , the same X , Y point elevation differences issue .System can also test whether there is an internal DEM data files or invalid value zero height point and the inspection results to the DAT file ( a text file containing coordinates ) to show the way to the operator for the production of completeness DEM tes-ting and work .

  17. LULC Classification and Topographic Correction of Landsat-7 ETM+ Imagery in the Yangjia River Watershed: the Influence of DEM Resolution.

    Science.gov (United States)

    Gao, Yongnian; Zhang, Wanchang

    2009-01-01

    DEM-based topographic corrections on Landsat-7 ETM+ imagery from rugged terrain, as an effective processing techniques to improve the accuracy of Land Use/Land Cover (LULC) classification as well as land surface parameter retrievals with remotely sensed data, has been frequently reported in the literature. However, few studies have investigated the exact effects of DEM with different resolutions on the correction of imagery. Taking the topographic corrections on the Landsat-7 ETM+ images acquired from the rugged terrain of the Yangjiahe river basin (P.R. China) as an example, the present work systematically investigates such issues by means of two commonly used topographic correction algorithms with the support of different spatial resolution DEMs. After the pre-processing procedures, i.e. atmospheric correction and geo-registration, were applied to the ETM+ images, two topographic correction algorithms, namely SCS correction and Minnaert correction, were applied to assess the effects of different spatial resolution DEMs obtained from two sources in the removal of topographic effects and LULC classifications. The results suggested that the topographic effects were tremendously reduced with these two algorithms under the support of different spatial resolution DEMs, and the performance of the topographic correction with the 1:50,000-topographic-map DEM was similar to that achieved using SRTM DEM. Moreover, when the same topographic correction algorithm was applied the accuracy of LULC classification after topographic correction based on 1:50,000-topographic-map DEM was similar as that based on SRTM DEM, which implies that the 90 m SRTM DEM can be used as an alternative for the topographic correction of ETM+ imagery when high resolution DEM is unavailable.

  18. Influence of Lossy Compressed DEM on Radiometric Correction for Land Cover Classification of Remote Sensing Images

    Science.gov (United States)

    Moré, G.; Pesquer, L.; Blanes, I.; Serra-Sagristà, J.; Pons, X.

    2012-12-01

    World coverage Digital Elevation Models (DEM) have progressively increased their spatial resolution (e.g., ETOPO, SRTM, or Aster GDEM) and, consequently, their storage requirements. On the other hand, lossy data compression facilitates accessing, sharing and transmitting large spatial datasets in environments with limited storage. However, since lossy compression modifies the original information, rigorous studies are needed to understand its effects and consequences. The present work analyzes the influence of DEM quality -modified by lossy compression-, on the radiometric correction of remote sensing imagery, and the eventual propagation of the uncertainty in the resulting land cover classification. Radiometric correction is usually composed of two parts: atmospheric correction and topographical correction. For topographical correction, DEM provides the altimetry information that allows modeling the incidence radiation on terrain surface (cast shadows, self shadows, etc). To quantify the effects of the DEM lossy compression on the radiometric correction, we use radiometrically corrected images for classification purposes, and compare the accuracy of two standard coding techniques for a wide range of compression ratios. The DEM has been obtained by resampling the DEM v.2 of Catalonia (ICC), originally having 15 m resolution, to the Landsat TM resolution. The Aster DEM has been used to fill the gaps beyond the administrative limits of Catalonia. The DEM has been lossy compressed with two coding standards at compression ratios 5:1, 10:1, 20:1, 100:1 and 200:1. The employed coding standards have been JPEG2000 and CCSDS-IDC; the former is an international ISO/ITU-T standard for almost any type of images, while the latter is a recommendation of the CCSDS consortium for mono-component remote sensing images. Both techniques are wavelet-based followed by an entropy-coding stage. Also, for large compression ratios, both techniques need a post processing for correctly

  19. San Francisco Bay-Delta bathymetric/topographic digital elevation model (DEM)

    Science.gov (United States)

    Fregoso, Theresa; Wang, Rueen-Fang; Ateljevich, Eli; Jaffe, Bruce E.

    2017-01-01

    A high-resolution (10-meter per pixel) digital elevation model (DEM) was created for the Sacramento-San Joaquin Delta using both bathymetry and topography data. This DEM is the result of collaborative efforts of the U.S. Geological Survey (USGS) and the California Department of Water Resources (DWR). The base of the DEM is from a 10-m DEM released in 2004 and updated in 2005 (Foxgrover and others, 2005) that used Environmental Systems Research Institute (ESRI), ArcGIS Topo to Raster module to interpolate grids from single beam bathymetric surveys collected by DWR, the Army Corp of Engineers (COE), the National Oceanic and Atmospheric Administration (NOAA), and the USGS, into a continuous surface. The Topo to Raster interpolation method was specifically designed to create hydrologically correct DEMs from point, line, and polygon data (Environmental Systems Research Institute, Inc., 2015). Elevation contour lines were digitized based on the single beam point data for control of channel morphology during the interpolation process. Checks were performed to ensure that the interpolated surfaces honored the source bathymetry, and additional contours and (or) point data were added as needed to help constrain the data. The original data were collected in the tidal datum Mean Lower or Low Water (MLLW) or the National Geodetic Vertical Datum of 1929 (NGVD29). All data were converted to NGVD29.The 2005 USGS DEM was updated by DWR, first by converting the DEM to the current modern datum of North American Vertical Datum of 1988 (NAVD88) and then by following the methodology of the USGS DEM, established for the 2005 DEM (Foxgrover and others, 2005) for adding newly collected single and multibeam bathymetric data. They then included topographic data from lidar surveys, providing the first DEM that included the land/water interface (Wang and Ateljevich, 2012).The USGS further updated and expanded the DWR DEM with the inclusion of USGS interpolated sections of single beam

  20. Optimierung der Hefetechnologie mit dem Ziel einer Verbesserung der Geschmacksstabilität im Praxismaßstab

    OpenAIRE

    Hartwig, Axel

    2008-01-01

    Die Planung und Inbetriebnahme eines neuen Hefeherführsystems in Form einer Assimilationsanlage sowie großtechnische Gärversuche an 3-Sud-ZKGs mit Variation verschiedener Anstellparameter zur Erhöhung des SO2-Gehaltes des Bieres stellen den Kern der Arbeit dar. Im Rahmen von Versuchsreihen an Assimilationen unter Einsatz von drei verschiedenen Belüftungssystemen konnte gezeigt werden, dass eine einfache Belüftungsvorrichtung in Form eines T-Stücks mit Luftzufuhr durch ein perforiertes Rohr...

  1. Korrelation der Explosionsheftigkeit mit der spezifischen Oberfläche und dem Brennwert von Stäuben

    OpenAIRE

    Gerhold, Malte

    2017-01-01

    In vielen Industrie- und Gewerbebereichen kommt es immer wieder zu Staubexplosionen, die regelmäßig zu erheblichen Sach- und Personenschäden führen. Zur Charakterisierung des Ex-plosionsverhaltens von Stäuben dienen verschiedene, experimentell ermittelte Kenngrößen. Diese beschreiben zum einen das Zündverhalten, zum anderen die Explosionsheftigkeit eines Staub/Luft-Gemischs. Gegenstand dieser Arbeit sind die Kenngrößen maximaler Explosions-überdruck und maximale Druckanstiegsgeschwindigkeit, ...

  2. Simulation of the influence of tar formation in wood gasification processes on the cost of the purified process gas; Simulation des Einflusses der Teerbildung bei der Vergasung von Holz auf die Kosten des gereinigten Produktgases

    Energy Technology Data Exchange (ETDEWEB)

    Saller, G.; Krumm, W. [Siegen Univ. (Gesamthochschule) (Germany). Inst. fuer Energietechnik

    1998-09-01

    The influence of the gasification process and the related tar formation rate on the cost of gas production is investigated with the aid of process models. The processes of gasification, gas purification and adsorptive treatment of waste water were modelled mathematically with a view to process mechanisms and cost. Simulations of the overall process helped to obtain a quantitative assessment of the cost of product gas as a function of process parameters like gasification process and tar formation. (orig./SR) [Deutsch] Mit Hilfe von Prozessmodellen wird untersucht, welchen Einfluss das Vergasungsverfahren und die damit verbundene Teerbildung mit entsprechenden Reinigungsverfahren auf die Produktionskosten des gereinigten Produktgases besitzt. Hierfuer werden die Prozesse der Vergasung, Gasreinigung und adsorptiven Abwasseraufbereitung hinsichtlich verfahrenstechnischer Zusammenhaenge und Kosten mathematisch modelliert. Durch Simulation des Gesamtprozesses werden quantitativ die Kosten des Produktgases in Abhaengigkeit von Prozessparametern wie Vergasungsverfahren und Teerbildung ermittelt. (orig./SR)

  3. Influence of the boundary condition at the channel inlet on the simulation of a speed-controlled turbine system with a feed channel; Einfluss der Randbedingung am Kanalanfang auf die Simulation einer drehzahlgeregelten Turbinenanlage mit Zuleitungskanal

    Energy Technology Data Exchange (ETDEWEB)

    Ott, C.

    1994-12-31

    This study on speed control of turbines with a short feed channel shows that the formulation of the boundary conditions at the channel inlet bears strongly on the attenuation behaviour of the system. Neglecting kinetic energy and inlet losses affects the dynamic behaviour of the system to such an extent as to cause numerical instability. (orig./AKF) [Deutsch] Bei der vorliegenden Untersuchung ueber die Drehzahlregelung von Turbinen mit einem kurzen Zuleitungskanal wird deutlich, dass die Formulierung der Randbedingung am Kanalanfang einen starken Einfluss auf das Daempfungsverhalten der Anlage hat. Die Vernachlaessigung der kinetischen Energie und der Einlaufverluste beeinflusst das dynamische Verhalten der Anlage so stark, dass sie rechnerisch instabil wird. (orig./AKF)

  4. High-Accuracy Tidal Flat Digital Elevation Model Construction Using TanDEM-X Science Phase Data

    Science.gov (United States)

    Lee, Seung-Kuk; Ryu, Joo-Hyung

    2017-01-01

    This study explored the feasibility of using TanDEM-X (TDX) interferometric observations of tidal flats for digital elevation model (DEM) construction. Our goal was to generate high-precision DEMs in tidal flat areas, because accurate intertidal zone data are essential for monitoring coastal environment sand erosion processes. To monitor dynamic coastal changes caused by waves, currents, and tides, very accurate DEMs with high spatial resolution are required. The bi- and monostatic modes of the TDX interferometer employed during the TDX science phase provided a great opportunity for highly accurate intertidal DEM construction using radar interferometry with no time lag (bistatic mode) or an approximately 10-s temporal baseline (monostatic mode) between the master and slave synthetic aperture radar image acquisitions. In this study, DEM construction in tidal flat areas was first optimized based on the TDX system parameters used in various TDX modes. We successfully generated intertidal zone DEMs with 57-m spatial resolutions and interferometric height accuracies better than 0.15 m for three representative tidal flats on the west coast of the Korean Peninsula. Finally, we validated these TDX DEMs against real-time kinematic-GPS measurements acquired in two tidal flat areas; the correlation coefficient was 0.97 with a root mean square error of 0.20 m.

  5. Lidar DEM error analyses and topographic depression identification in a hummocky landscape in the prairie region of Canada

    Science.gov (United States)

    Li, Sheng; MacMillan, R. A.; Lobb, David A.; McConkey, Brian G.; Moulin, Alan; Fraser, Walter R.

    2011-06-01

    Topographic depressions are abundant in topographically complex landscapes. A common practice with earlier, low resolution Digital Elevation Models (DEMs) was to remove all depressions to ensure that water flowed continuously to the edge of the DEM domain. The assumption was that most depressions were created due to errors in the DEMs. This practice is no longer justified with the increasing availability of high accuracy DEMs. However, very few studies have addressed how DEM processing options such as smoothing and coarsening and setting area and depth thresholds can affect depression identification. In this study, a site located in the Prairie Region of Canada was examined. The site is a hummocky glaciated landscape with many in-field wetlands. Lidar topographic data were collected and were used to generate a 1 m by 1 m square-grid DEM. Detailed error analyses of the lidar DEM were conducted. A set of DEMs were generated after different degrees of smoothing and coarsening. FlowMapR, an established terrain analysis tool, was used to identify depressions in each DEM with various user-defined area and depth thresholds. The results were validated against a field wetland survey. We determined that the problems associated with depression identification using a lidar DEM are two-fold. On one hand, artefactual depressions created due to DEM errors need to be eliminated, for which the raw lidar DEM need to be smoothed. On the other hand, it is also desirable to remove those topographic depressions that do not function as closed basins at the spatial or temporal scale of the processes of interest. Setting area and depth thresholds appeared to be the preferred choice for this. We suggested using the un-autocorrelated lidar DEM error as the criterion for DEM smoothing and considering depression connections in the selection of area and depth thresholds. Using lidar data on a hummocky landscape with loamy soils in the Prairie Region of Canada, 10 to 20 times smoothing

  6. Evaluating DEM conditioning techniques, elevation source data, and grid resolution for field-scale hydrological parameter extraction

    Science.gov (United States)

    Woodrow, Kathryn; Lindsay, John B.; Berg, Aaron A.

    2016-09-01

    Although digital elevation models (DEMs) prove useful for a number of hydrological applications, they are often the end result of numerous processing steps that each contains uncertainty. These uncertainties have the potential to greatly influence DEM quality and to further propagate to DEM-derived attributes including derived surface and near-surface drainage patterns. This research examines the impacts of DEM grid resolution, elevation source data, and conditioning techniques on the spatial and statistical distribution of field-scale hydrological attributes for a 12,000 ha watershed of an agricultural area within southwestern Ontario, Canada. Three conditioning techniques, including depression filling (DF), depression breaching (DB), and stream burning (SB), were examined. The catchments draining to each boundary of 7933 agricultural fields were delineated using the surface drainage patterns modeled from LiDAR data, interpolated to a 1 m, 5 m, and 10 m resolution DEMs, and from a 10 m resolution photogrammetric DEM. The results showed that variation in DEM grid resolution resulted in significant differences in the spatial and statistical distributions of contributing areas and the distributions of downslope flowpath length. Degrading the grid resolution of the LiDAR data from 1 m to 10 m resulted in a disagreement in mapped contributing areas of between 29.4% and 37.3% of the study area, depending on the DEM conditioning technique. The disagreements among the field-scale contributing areas mapped from the 10 m LiDAR DEM and photogrammetric DEM were large, with nearly half of the study area draining to alternate field boundaries. Differences in derived contributing areas and flowpaths among various conditioning techniques increased substantially at finer grid resolutions, with the largest disagreement among mapped contributing areas occurring between the 1 m resolution DB DEM and the SB DEM (37% disagreement) and the DB-DF comparison (36.5% disagreement in mapped

  7. Ueber von Hominiden bearbeitete Knochenfunde aus dem oberen Villafranchien in den Niederlanden

    NARCIS (Netherlands)

    Lüttschwager, Joh.; Bemmel, van A.C.V.

    1962-01-01

    Die Funde von Vertebratenknochen in dem Ton von Tegelen bei Venlo (Provinz Zuid Limburg, Niederlande), sind schon lange bekannt und eingehend bearbeitet worden (SCHREUDER, 1945). Die dunkelbraunen, meist gut erhaltenen Knochen, liegen im blauen Ton eingebettet. Ohne Zweifel sind die Reste einst vom

  8. DEM GPU studies of industrial scale particle simulations for granular flow civil engineering applications

    Science.gov (United States)

    Pizette, Patrick; Govender, Nicolin; Wilke, Daniel N.; Abriak, Nor-Edine

    2017-06-01

    The use of the Discrete Element Method (DEM) for industrial civil engineering industrial applications is currently limited due to the computational demands when large numbers of particles are considered. The graphics processing unit (GPU) with its highly parallelized hardware architecture shows potential to enable solution of civil engineering problems using discrete granular approaches. We demonstrate in this study the pratical utility of a validated GPU-enabled DEM modeling environment to simulate industrial scale granular problems. As illustration, the flow discharge of storage silos using 8 and 17 million particles is considered. DEM simulations have been performed to investigate the influence of particle size (equivalent size for the 20/40-mesh gravel) and induced shear stress for two hopper shapes. The preliminary results indicate that the shape of the hopper significantly influences the discharge rates for the same material. Specifically, this work shows that GPU-enabled DEM modeling environments can model industrial scale problems on a single portable computer within a day for 30 seconds of process time.

  9. DEM resolution effects on shallow landslide hazard and soil redistribution modelling

    NARCIS (Netherlands)

    Claessens, L.F.G.; Heuvelink, G.B.M.; Schoorl, J.M.; Veldkamp, A.

    2005-01-01

    In this paper we analyse the effects of digital elevation model (DEM) resolution on the results of a model that simulates spatially explicit relative shallow landslide hazard and soil redistribution patterns and quantities. We analyse distributions of slope, specific catchment area and relative haza

  10. The Three Dimensional Douglas-Peucker Algorithm for Generalization between River Network Line Element and DEM

    Directory of Open Access Journals (Sweden)

    DOU Shiqing

    2016-04-01

    Full Text Available At present, the three dimensional Douglas-Peucker (3D_DP algorithm is mainly used on generalization of a single type of DEM. This paper introduces the "bending adjustment index" to improve the 3D_DP algorithm, and puts forward a new method for generalizing river network and DEM in three-dimensional space. In this method, river network line vector data are extracted into 3D discrete point data sets which are added elevation attributes, and then they are merged with the 3D discrete point data sets of DEM. The generalization operations are made by the improved 3D_DP algorithm after the hierarchical selection of river networks. Through the contrast and analysis of the experimental results, the well experiment results have been achieved. Under the role of bending adjustment index, the overall distribution form of the rivers and the main terrain features can be reserved reasonably on the generalization. The river network and DEM data were generalized under the same simplified factor in this method. It improves the quality of the cartography generalization.

  11. Discrete element simulation of mill charge in 3D using the BLAZE-DEM GPU framework

    CSIR Research Space (South Africa)

    Govender, Nicolin

    2015-08-01

    Full Text Available The Discrete Element Method (DEM) simulation of charge motion in ball, semi autogenous (SAG) and autogenous mills has advanced to a stage where the effects of lifter design, power draft and product size can be evaluated with sufficient accuracy...

  12. Diffusion-Based Coarse Graining in Hybrid Continuum--Discrete Solvers: Applications in CFD--DEM

    CERN Document Server

    Sun, Rui

    2014-01-01

    In this work, a coarse graining method previously proposed by the authors based on solving diffusion equations is applied to CFD--DEM simulations, where coarse graining is used to obtain solid volume fraction, particle phase velocity, and fluid--particle interaction forces. By examining the conservation requirements, the variables to solve diffusion equations for in CFD--DEM simulations are identified. The algorithm is then implemented to a CFD--DEM solver based on OpenFOAM and LAMMPS, the former being a general-purpose, three-dimensional CFD solver based on unstructured meshes. Numerical simulations are performed for a fluidized bed by using the CFD--DEM solver with the diffusion-based coarse graining algorithm. Converged results are obtained on successively refined meshes, even for meshes with cell sizes comparable to or smaller than the particle diameter. This is a critical advantage of the proposed method over many existing coarse graining methods, and would be particularly valuable when small cells are r...

  13. Estimating Horizontal Displacement between DEMs by Means of Particle Image Velocimetry Techniques

    Directory of Open Access Journals (Sweden)

    Juan F. Reinoso

    2015-12-01

    Full Text Available To date, digital terrain model (DTM accuracy has been studied almost exclusively by computing its height variable. However, the largely ignored horizontal component bears a great influence on the positional accuracy of certain linear features, e.g., in hydrological features. In an effort to fill this gap, we propose a means of measurement different from the geomatic approach, involving fluid mechanics (water and air flows or aerodynamics. The particle image velocimetry (PIV algorithm is proposed as an estimator of horizontal differences between digital elevation models (DEM in grid format. After applying a scale factor to the displacement estimated by the PIV algorithm, the mean error predicted is around one-seventh of the cell size of the DEM with the greatest spatial resolution, and around one-nineteenth of the cell size of the DEM with the least spatial resolution. Our methodology allows all kinds of DTMs to be compared once they are transformed into DEM format, while also allowing comparison of data from diverse capture methods, i.e., LiDAR versus photogrammetric data sources.

  14. Extracting DEM from airborne X-band data based on PolInSAR

    Science.gov (United States)

    Hou, X. X.; Huang, G. M.; Zhao, Z.

    2015-06-01

    Polarimetric Interferometric Synthetic Aperture Radar (PolInSAR) is a new trend of SAR remote sensing technology which combined polarized multichannel information and Interferometric information. It is of great significance for extracting DEM in some regions with low precision of DEM such as vegetation coverage area and building concentrated area. In this paper we describe our experiments with high-resolution X-band full Polarimetric SAR data acquired by a dual-baseline interferometric airborne SAR system over an area of Danling in southern China. Pauli algorithm is used to generate the double polarimetric interferometry data, Singular Value Decomposition (SVD), Numerical Radius (NR) and Phase diversity (PD) methods are used to generate the full polarimetric interferometry data. Then we can make use of the polarimetric interferometric information to extract DEM with processing of pre filtering , image registration, image resampling, coherence optimization, multilook processing, flat-earth removal, interferogram filtering, phase unwrapping, parameter calibration, height derivation and geo-coding. The processing system named SARPlore has been exploited based on VC++ led by Chinese Academy of Surveying and Mapping. Finally compared optimization results with the single polarimetric interferometry, it has been observed that optimization ways can reduce the interferometric noise and the phase unwrapping residuals, and improve the precision of DEM. The result of full polarimetric interferometry is better than double polarimetric interferometry. Meanwhile, in different terrain, the result of full polarimetric interferometry will have a different degree of increase.

  15. Dem Extraction from CHANG'E-1 Lam Data by Surface Skinning Technology

    Science.gov (United States)

    Zhang, X.-B.; Zhang, W.-M.

    2011-08-01

    DEM is a digital model or 3-D representation of a terrain's surface and it is created from terrain elevation data. The main models for DEM extraction based on Lidar data or Laser Altimeter data currently use the idea that point cloud is scattered, such as regular grid model, TIN model and contour model. Essentially, in these above methods, the discrete points are interpolated into regular grid data and irregular grid data. In fact, point cloud generated by Laser Altimeter is not totally scattered, but have some regularity. In this paper, to utilize this regularity, the proposed method adopts surface skinning technology to generate DEM from Chang'E-1 Laser Altimeter data. The surface skinning technology is widely used in the field of mechanical engineering. Surface skinning is the process of passing a smooth surface through a set of curves called sectional curves, which, in general, may not be compatible. In the process of generating section line, a need for attention is that it needs to use curvature method to get a set of characteristic points, and these feature points were used to subdivide segment; the next step is generating several curves on some key places. These curves describe the shape of the curved surface. The last step is to generate a curved surface that through these curves. The result shows that, this idea is feasible, useful and it provides a novel way to generate accurate DEM.

  16. DEM Simulation of Biaxial Compression Experiments of Inherently Anisotropic Granular Materials and the Boundary Effects

    Directory of Open Access Journals (Sweden)

    Zhao-Xia Tong

    2013-01-01

    Full Text Available The reliability of discrete element method (DEM numerical simulations is significantly dependent on the particle-scale parameters and boundary conditions. To verify the DEM models, two series of biaxial compression tests on ellipse-shaped steel rods are used. The comparisons on the stress-strain relationship, strength, and deformation pattern of experiments and simulations indicate that the DEM models are able to capture the key macro- and micromechanical behavior of inherently anisotropic granular materials with high fidelity. By using the validated DEM models, the boundary effects on the macrodeformation, strain localization, and nonuniformity of stress distribution inside the specimens are investigated using two rigid boundaries and one flexible boundary. The results demonstrate that the boundary condition plays a significant role on the stress-strain relationship and strength of granular materials with inherent fabric anisotropy if the stresses are calculated by the force applied on the wall. However, the responses of the particle assembly measured inside the specimens are almost the same with little influence from the boundary conditions. The peak friction angle obtained from the compression tests with flexible boundary represents the real friction angle of particle assembly. Due to the weak lateral constraints, the degree of stress nonuniformity under flexible boundary is higher than that under rigid boundary.

  17. Rockslide and Impulse Wave Modelling in the Vajont Reservoir by DEM-CFD Analyses

    Science.gov (United States)

    Zhao, T.; Utili, S.; Crosta, G. B.

    2016-06-01

    This paper investigates the generation of hydrodynamic water waves due to rockslides plunging into a water reservoir. Quasi-3D DEM analyses in plane strain by a coupled DEM-CFD code are adopted to simulate the rockslide from its onset to the impact with the still water and the subsequent generation of the wave. The employed numerical tools and upscaling of hydraulic properties allow predicting a physical response in broad agreement with the observations notwithstanding the assumptions and characteristics of the adopted methods. The results obtained by the DEM-CFD coupled approach are compared to those published in the literature and those presented by Crosta et al. (Landslide spreading, impulse waves and modelling of the Vajont rockslide. Rock mechanics, 2014) in a companion paper obtained through an ALE-FEM method. Analyses performed along two cross sections are representative of the limit conditions of the eastern and western slope sectors. The max rockslide average velocity and the water wave velocity reach ca. 22 and 20 m/s, respectively. The maximum computed run up amounts to ca. 120 and 170 m for the eastern and western lobe cross sections, respectively. These values are reasonably similar to those recorded during the event (i.e. ca. 130 and 190 m, respectively). Therefore, the overall study lays out a possible DEM-CFD framework for the modelling of the generation of the hydrodynamic wave due to the impact of a rapid moving rockslide or rock-debris avalanche.

  18. New land-based method for surveying sandy shores and extracting DEMs: the INSHORE system.

    Science.gov (United States)

    Baptista, Paulo; Cunha, Telmo R; Matias, Ana; Gama, Cristina; Bernardes, Cristina; Ferreira, Oscar

    2011-11-01

    The INSHORE system (INtegrated System for High Operational REsolution in shore monitoring) is a land-base survey system designed and developed for the specific task of monitoring the evolution in time of sandy shores. This system was developed with two main objectives: (1) to produce highly accurate 3D coordinates of surface points (in the order of 0.02 to 0.03 m); and (2) to be extremely efficient in surveying a beach stretch of several kilometres. Previous tests have demonstrated that INSHORE systems fulfil such objectives. Now, the usefulness of the INSHORE system as a survey tool for the production of Digital Elevation Models (DEMs) of sandy shores is demonstrated. For this purpose, the comparison of DEMs obtained with the INSHORE system and with other relevant survey techniques is presented. This comparison focuses on the final DEM accuracy and also on the survey efficiency and its impact on the costs associated with regular monitoring programmes. The field survey method of the INSHORE system, based on profile networks, has a productivity of about 30 to 40 ha/h, depending on the beach surface characteristics. The final DEM precision, after interpolation of the global positioning system profile network, is approximately 0.08 to 0.12 m (RMS), depending on the profile network's density. Thus, this is a useful method for 3D representation of sandy shore surfaces and can permit, after interpolation, reliable calculations of volume and other physical parameters.

  19. Fluid–particle flow simulations using two-way-coupled mesoscale SPH–DEM and validation

    NARCIS (Netherlands)

    Robinson, M.J.; Luding, S.; Ramaioli, Marco

    2013-01-01

    First, a meshless simulation method is presented for multiphase fluid–particle flows with a two-way coupled Smoothed Particle Hydrodynamics (SPH) for the fluid and the Discrete Element Method (DEM) for the solid phase. The unresolved fluid model, based on the locally averaged Navier Stokes equations

  20. Ueber von Hominiden bearbeitete Knochenfunde aus dem oberen Villafranchien in den Niederlanden

    NARCIS (Netherlands)

    Lüttschwager, Joh.; Bemmel, van A.C.V.

    1962-01-01

    Die Funde von Vertebratenknochen in dem Ton von Tegelen bei Venlo (Provinz Zuid Limburg, Niederlande), sind schon lange bekannt und eingehend bearbeitet worden (SCHREUDER, 1945). Die dunkelbraunen, meist gut erhaltenen Knochen, liegen im blauen Ton eingebettet. Ohne Zweifel sind die Reste einst vom

  1. Three-dimensional DEM theory and its application to impact mechanics

    Institute of Scientific and Technical Information of China (English)

    唐志平

    2001-01-01

    In this paper, three-dimensional (3D) DEM theory has been explored and applied to impact simulation. The calculated results fit the experimental observation quite well, showing that this method can be applied to the simulation of the impact responses and the analysis of the mechanisms for materials and structures with defects, heterogeneity, multi-phase, even with phase and chemical changes.

  2. Die Geburt des Kosmos aus dem Nichts die Theorie des inflationären Universums

    CERN Document Server

    Guth, Alan

    2002-01-01

    Selten wird die Wissenschaft über Nacht so stark revolutioniert wie die Kosmologie durch Alan Guths Entdeckung der inflationären Theorie des Universums. Noch seltener gelingt es dem Urheber einer solchen Revolution, eine derart verständliche und einprägsame Darstellung von einer der aufregendsten Epochen in der modernen Kosmologie zu geben. Sogar Kenner werden Neues lernen.

  3. A problem-oriented approach for DEM data management and manipulation

    Science.gov (United States)

    Huang, Fengru; Fang, Yu; Chen, Bin

    2009-10-01

    For the last decades, GIS software technologies have made tremendous development and applied to many special fields when their targets are relevant to geographical locations. But the basis of cartographic mapping of GIS is a restriction for more development in GIS data modelling, storage and manipulation. Recently, much attention is being paid on ORDBMS(Object Relational Database Management System) to represent and manage GIS Data. New approaches have earned acceptance in many research communities and several proposals have emerged in commercial software for solving the management and manipulation on GIS vector data. Though the storage and management of field-based model data(e.g. raster, DEM, TIN) have got less achievement and people still use files and procedural ways to manipulation field-based GIS data in common applications. In this paper a new structure model using ORDBMS technology for field-based data's storage and management was proposed on the basis of full discussion on several GIS data management technologies, then a problem-oriented approach for DEM data management and manipulation was designed and implemented through open source software systems PostgreSQL and Python language. Experimental examples of different DEM data souces were stored, managed and used by using the extended spatial database system. The experiments illustrated that this solution would be a useful supplement to spatial database and it provided an effective way to DEM data management and analysis, and support the interoperability between vector data and field data.

  4. Effect of DEM resolution and comparison between different weighting factors for hydrologic connectivity index

    Science.gov (United States)

    Cantreul, Vincent; Cavalli, Marco; Degré, Aurore

    2016-04-01

    The emerging concept of hydrological connectivity is difficult to quantify. Some indices have been proposed. The most cited is Borselli's one. It mainly uses the DEM as input. The pixel size may strongly impacts the result of the calculation. It has not been studied yet in silty areas. Another important aspect is the choice of the weighting factor which strongly influences the index value. The objective of this poster is so to compare 8 different DEM's resolutions (12, 24, 48, 72, 96, 204, 504 and 996cm) and 3 different weighting factors (factor C of Wischmeier, Manning's factor and rugosity index) in the Borselli's index calculation. The IC was calculated in a 124ha catchment (Hevillers), in the loess belt, in Belgium. The DEM used is coming from a UAV with a maximum resolution of 12 cm. Permanent covered surfaces are not considered in order to avoid artefact due to the vegetation (2% of the surface). Regarding the DEM pixel size, the IC increases for a given pixel when the pixel size decreases. That confirms some results observed in the Alpine region by Cavalli (2014). The mean difference between 12 cm and 10 m resolution is 35% with higher values up to 100% for higher connectivity zones (flow paths). Another result is the lower impact of connections in the watershed (grass strips…) at lower pixel sizes. This is linked to the small width of some connections which are sometimes comparing to cell size. Furthermore, a great loss of precision is observed from the 500 cm pixel size and upper. That remark is quite intuitive. Finally, some very well disconnected zones appear for the highest resolutions. Regarding the weighting factor, IC values calculated using C factor are lower than with the rugosity index which is only a topographic factor. With very high resolution DEM, it permits to represent the fine topography. For the C factor, the zones up to very well disconnected areas (grass strips, wood…) are well represented with lower index values than downstream

  5. DEM sourcing guidelines for computing 1 Eö accurate terrain corrections for airborne gravity gradiometry

    Science.gov (United States)

    Annecchione, Maria; Hatch, David; Hefford, Shane W.

    2017-01-01

    In this paper we investigate digital elevation model (DEM) sourcing requirements to compute gravity gradiometry terrain corrections accurate to 1 Eötvös (Eö) at observation heights of 80 m or more above ground. Such survey heights are typical in fixed-wing airborne surveying for resource exploration where the maximum signal-to-noise ratio is sought. We consider the accuracy of terrain corrections relevant for recent commercial airborne gravity gradiometry systems operating at the 10 Eö noise level and for future systems with a target noise level of 1 Eö. We focus on the requirements for the vertical gradient of the vertical component of gravity (Gdd) because this element of the gradient tensor is most commonly interpreted qualitatively and quantitatively. Terrain correction accuracy depends on the bare-earth DEM accuracy and spatial resolution. The bare-earth DEM accuracy and spatial resolution depends on its source. Two possible sources are considered: airborne LiDAR and Shuttle Radar Topography Mission (SRTM). The accuracy of an SRTM DEM is affected by vegetation height. The SRTM footprint is also larger and the DEM resolution is thus lower. However, resolution requirements relax as relief decreases. Publicly available LiDAR data and 1 arc-second and 3 arc-second SRTM data were selected over four study areas representing end member cases of vegetation cover and relief. The four study areas are presented as reference material for processing airborne gravity gradiometry data at the 1 Eö noise level with 50 m spatial resolution. From this investigation we find that to achieve 1 Eö accuracy in the terrain correction at 80 m height airborne LiDAR data are required even when terrain relief is a few tens of meters and the vegetation is sparse. However, as satellite ranging technologies progress bare-earth DEMs of sufficient accuracy and resolution may be sourced at lesser cost. We found that a bare-earth DEM of 10 m resolution and 2 m accuracy are sufficient for

  6. Clinical application of leucocyte scintigraphy with the monoclonal antibody MAK BW 250/183 with special regard to the induction of antimurine antibodies (HAMA); Leukozytenszintigraphie mit dem monoklonalen Antikoerper MAK BW 250/183 in der klinischen Anwendung unter Beruecksichtigung der Induktion von antimurinen Antikoerpern (HAMA)

    Energy Technology Data Exchange (ETDEWEB)

    Eising, E.G. [Klinik und Poliklinik fuer Nuklearmedizin der Universitaet-GH, Essen (Germany); Reiners, C. [Klinik und Poliklinik fuer Nuklearmedizin der Universitaet-GH, Essen (Germany); Farahati, J. [Klinik und Poliklinik fuer Nuklearmedizin der Universitaet-GH, Essen (Germany); Jacob, M. [Klinik und Poliklinik fuer Nuklearmedizin der Universitaet-GH, Essen (Germany)

    1994-12-31

    Scintigraphy with the murine antibody MAK BW 250/183 (Scintimun Granulozyt{sup R}) has proven to be a good imaging method to clear up clinical questions concerning acute inflammatory processes. 30 patients with clinical signs of acute inflammation were included in this prospective study to test the clinical usefulness of this tracer and possible negative influences by anti-murine antibodies (HAMA). Side effects or induction of HAMA antibodies couldn`t be observed in any patients. The quality of the obtained images was good in all cases. However, false negative results were obtained in cases on antiphlogistic medication (e.g. cortisone) or with chronic inflammatory diseases. Application of MAK BW 250/183 (Scintimum Granulozyt{sup R}) should be avoided in children due to its relative high radiation dose to bone marrow. False negative results can be found in inflammatory lesions of axial sceleton. On the other hand, the good contrast of bone marrow can be used in patients to diagnose pathologic alterations of bone marrow distribution. (orig.) [Deutsch] Bei erwachsenen Patienten mit dem gezielten Verdacht auf akute entzuendliche Veraenderungen stellt die Anti-Granulozyten-Szintigraphie eine Methode mit relativ guter Bildgebung und Aussagefaehigkeit dar. Zur Ueberpruefung der klinischen Wertigkeit der Anti-Granulozyten-Szintrigraphie mit dem monoklonalen, murinen Antikoerper MAK BW 250/183 (Scintimun Granulozyt{sup R}) wurden 30 Patienten in einer prospektiv angelegten Studie untersucht. Insbesondere wurde hierbei auch die Ausbildung von signifikanten Antikoerpertitern gegen den MAK ueberprueft und deren Einfluss auf die szintigraphische Bildgebung evaluiert. Nebenwirkungen oder die Ausbildung von Antikoerpern (HAMA) wurden bei Patienten innerhalb der Studie nicht beobachtet. Auch die erhaltenen szintigraphischen Aufnahmen waren durchweg gut beurteilbar. Entzuendungen unter Antiphlogistika (insbesondere Cortisonpraeparate) sowie laengerfristig bestehende Entzuendungen

  7. Bolter miner operation at Walsum colliery; Der Einsatz des Bolter-Miners auf dem Bergwerk Walsum

    Energy Technology Data Exchange (ETDEWEB)

    Mogk, E.; Kulassek, M. [Bergamt Moers (Germany); Traud, W.; Bender, B. [Bergbau AG Niederrhein, Duisburg (Germany). Bergwerk Walsum

    2002-09-05

    The characteristics of high performing development systems are worldwide mechanical headings in combination with rectangular bolted roadways. Such a high performing system should be introduced to the German hard coal industry with the aim of achieving an average drivage rate of 20 m/d. Central issues of this project were the continuation of the German safety philosophy, the adoption of world standard process technology and one supplier for the whole system. The system should be utilized DSK wide. In the year 2001 the heading system Bolter Miner 12 ED 15 from Joy in combination with the self-advancing Walking Tail End was employed for the first time at the Walsum colliery. During the short operating period of three months an average drivage rate of 8,3 m/d was achieved. The reasons have been analysed, as to why the maschine hasn't achieved it's demanded targets. However in concluding, it must be said that the choosen heading technique is generally efficient, safe and economical. (orig.) [German] Merkmale leistungsfaehiger Vortriebssysteme sind weltweit Rechteckankerstrecken mit maschineller Auffahrung. Im deutschen Steinkohlenbergbau sollte ein solches System eingefuehrt werden mit dem Ziel einer durchschnittlichen Auffahrleistung von 20 m/d. Kernpunkte des Projekts, an dem das Bergamt Moers von Anfang an beteiligt wurde, waren die Fortfuehrung der deutschen Sicherheitsphilosophie, die Uebernahme der Verfahrenstechnik des Weltstandards und ein Systemlieferant. Das System sollte DSK-weit einsetzbar sein. Im Jahr 2001 wurde daher auf dem Bergwerk Walsum erstmalig im deutschen Steinkohlenbergbau das Vortriebssystem Bolter Miner 12 ED 15 der Joy Mining Machinery Ltd. mit dem selbstschreitenden Nachlaeufer Walking Tail End eingesetzt. Waehrend der bisher kurzen Einsatzzeit von drei Monaten (Stand Januar 2002) wurde eine Durchschnittsauffahrung von 8,3 m/d erzielt. Trotz der nicht erbrachten geforderten Leistung, deren Gruende analysiert sind, bleibt im Ergebnis

  8. Inter-agency comparison of TanDEM-X baseline solutions

    Science.gov (United States)

    Jäggi, A.; Montenbruck, O.; Moon, Y.; Wermuth, M.; König, R.; Michalak, G.; Bock, H.; Bodenmann, D.

    2012-07-01

    TanDEM-X (TerraSAR-X add-on for Digital Elevation Measurement) is the first Synthetic Aperture Radar (SAR) mission using close formation flying for bistatic SAR interferometry. The primary goal of the mission is to generate a global digital elevation model (DEM) with 2 m height precision and 10 m ground resolution from the configurable SAR interferometer with space baselines of a few hundred meters. As a key mission requirement for the interferometric SAR processing, the relative position, or baseline vector, of the two satellites must be determined with an accuracy of 1 mm (1D RMS) from GPS measurements collected by the onboard receivers. The operational baseline products for the TanDEM-X mission are routinely generated by the German Research Center for Geosciences (GFZ) and the German Space Operations Center (DLR/GSOC) using different software packages (EPOS/BSW, GHOST) and analysis strategies. For a further independent performance assessment, TanDEM-X baseline solutions are generated at the Astronomical Institute of the University of Bern (AIUB) on a best effort basis using the Bernese Software (BSW). Dual-frequency baseline solutions are compared for a 1-month test period in January 2011. Differences of reduced-dynamic baseline solutions exhibit a representative standard deviation (STD) of 1 mm outside maneuver periods, while biases are below 1 mm in all directions. The achieved baseline determination performance is close to the mission specification, but independent SAR calibration data takes acquired over areas with a well known DEM from previous missions will be required to fully meet the 1 mm 1D RMS target. Besides the operational solutions, single-frequency baseline solutions are tested. They benefit from a more robust ambiguity fixing and show a slightly better agreement of below 1 mm STD, but are potentially affected by errors caused by an incomplete compensation of differential ionospheric path delays.

  9. Enhancements to TauDEM to support Rapid Watershed Delineation Services

    Science.gov (United States)

    Sazib, N. S.; Tarboton, D. G.

    2015-12-01

    Watersheds are widely recognized as the basic functional unit for water resources management studies and are important for a variety of problems in hydrology, ecology, and geomorphology. Nevertheless, delineating a watershed spread across a large region is still cumbersome due to the processing burden of working with large Digital Elevation Model. Terrain Analysis Using Digital Elevation Models (TauDEM) software supports the delineation of watersheds and stream networks from within desktop Geographic Information Systems. A rich set of watershed and stream network attributes are computed. However limitations of the TauDEM desktop tools are (1) it supports only one type of raster (tiff format) data (2) requires installation of software for parallel processing, and (3) data have to be in projected coordinate system. This paper presents enhancements to TauDEM that have been developed to extend its generality and support web based watershed delineation services. The enhancements of TauDEM include (1) reading and writing raster data with the open-source geospatial data abstraction library (GDAL) not limited to the tiff data format and (2) support for both geographic and projected coordinates. To support web services for rapid watershed delineation a procedure has been developed for sub setting the domain based on sub-catchments, with preprocessed data prepared for each catchment stored. This allows the watershed delineation to function locally, while extending to the full extent of watersheds using preprocessed information. Additional capabilities of this program includes computation of average watershed properties and geomorphic and channel network variables such as drainage density, shape factor, relief ratio and stream ordering. The updated version of TauDEM increases the practical applicability of it in terms of raster data type, size and coordinate system. The watershed delineation web service functionality is useful for web based software as service deployments

  10. Validation of DEMs Derived from High Resolution SAR Data: a Case Study on Barcelona

    Science.gov (United States)

    Sefercik, U. G.; Schunert, A.; Soergel, U.; Watanabe, K.

    2012-07-01

    In recent years, Synthetic Aperture Radar (SAR) data have been widely used for scientific applications and several SAR missions were realized. The active sensor principle and the signal wavelength in the order of centimeters provide all-day and all-weather capabilities, respectively. The modern German TerraSAR-X (TSX) satellite provides high spatial resolution down to one meter. Based on such data SAR Interferometry may yield high quality digital surface models (DSMs), which includes points located on 3d objects such as vegetation, forest, and elevated man-made structures. By removing these points, digital elevation model (DEM) representing the bare ground of Earth is obtained. The primary objective of this paper is the validation of DEMs obtained from TSX SAR data covering Barcelona area, Spain, in the framework of a scientific project conducted by ISPRS Working Group VII/2 "SAR Interferometry" that aims the evaluation of DEM derived from data of modern SAR satellite sensors. Towards this purpose, a DSM was generated with 10 m grid spacing using TSX StripMap mode SAR data and converted to a DEM by filtering. The accuracy results have been presented referring the comparison with a more accurate (10 cm-1 m) digital terrain model (DTM) derived from large scale photogrammetry. The results showed that the TSX DEM is quite coherent with the topography and the accuracy is in between ±8-10 m. As another application, the persistent scatterer interferometry (PSI) was conducted using TSX data and the outcomes were compared with a 3d city model available in Google Earth, which is known to be very precise because it is based on LIDAR data. The results showed that PSI outcomes are quite coherent with reference data and the RMSZ of differences is around 2.5 m.

  11. Co-ordinated field measurements on the influnce of leewaves on polar stratospheric clouds; Koordinierte Feldmessungen zum Einfluss von Leewellen auf Wolkenfelder in der polaren Stratosphaere

    Energy Technology Data Exchange (ETDEWEB)

    Reichardt, J.; Behrendt, A.; Baumgart, R.; Weitkamp, C. [GKSS-Forschungszentrum Geesthacht GmbH (Germany). Inst. fuer Physikalische und Chemische Analytik

    1999-07-01

    Within the framework of the project presented, the GKSS Raman lidar was deployed at the Swedish research facility ESRANGE (67.9 N, 21.1 E) in winters 1996/7 and 1997/8 for simultaneous measurements of ozone, polar stratospheric cloud (PSC) particle properties, and temperature. Both synoptic and mesoscale PSCs were observed under various meteorological conditions. On 16 Jan 1997 the complete life cycle of a leewave-induced PSC was measured. Four days later backscatter and depolarization ratios of a PSC Ia-enhanced were observed at UV wavelengths for the first time. A model was developed to compute 532 nm particle properties from these Raman lidar measurements. The calculated optical parameters agreed well with lidar measurements of this PSC type at 532 nm. Ozone profiles in PSCs were obtained during two PSC events. In winter 1997/8 temperature profiles were measured in PSCs and leewaves with the newly developed rotational Raman receiver without critical a-priori assumptions. The comparison of lidar temperatures with the European Centre for Medium Range Weather Forecast temperature analysis proved the values at the 10 hPa model level erroneous by up to 25 K. Optical and geometrical properties of arctic-winter cirrus clouds were analyed as well. Surprising spatial homogeneity in the parameter profiles was found. (orig.) [German] Im Rahmen des hier vorgestellten Projekts wurden mit dem GKSS-Ramanlidar in den Wintern 1996/7 und 1997/8 auf der schwedischen Forschungsstation ESRANGE (67.9 N, 21.1 E) gleichzeitig Ozonkonzentration, Partikeleigenschaften polarer stratosphaerischer Wolken (PSCs) und Temperatur bestimmt. Unter verschiedenen meteorologischen Bedingungen wurden sowohl synoptische als auch mesoskalige PSCs gemessen. Am 16. Januar 1997 wurde der vollstaendige Lebenszyklus einer leerwelleninduzierten PSC beobachtet. Vier Tage spaeter wurden erstmalig bei UV-Wellenlaengen Rueckstreu- und Depolarisationsverhaeltnisse der PSC Ia-enhanced gemessen. Zur Berechnung der

  12. AMES Stereo Pipeline Derived DEM Accuracy Experiment Using LROC-NAC Stereopairs and Weighted Spatial Dependence Simulation for Lunar Site Selection

    Science.gov (United States)

    Laura, J. R.; Miller, D.; Paul, M. V.

    2012-03-01

    An accuracy assessment of AMES Stereo Pipeline derived DEMs for lunar site selection using weighted spatial dependence simulation and a call for outside AMES derived DEMs to facilitate a statistical precision analysis.

  13. Assessment of neuro-optometric rehabilitation using the Developmental Eye Movement (DEM) test in adults with acquired brain injury.

    Science.gov (United States)

    Kapoor, Neera; Ciuffreda, Kenneth Joseph

    2017-07-01

    This pilot study sought to determine the efficacy of using the Developmental Eye Movement (DEM) test in the adult, acquired brain injury (ABI) population to quantify clinically the effects of controlled, laboratory-performed, oculomotor-based vision therapy/vision rehabilitation. Nine adult subjects with mild traumatic brain injury (mTBI) and five with stroke were assessed before and after an eight-week, computer-based, versional oculomotor (fixation, saccades, pursuit, and simulated reading) training program (9.6h total). The protocol incorporated a cross-over, interventional design with and without the addition of auditory feedback regarding two-dimensional eye position. The clinical outcome measure was the Developmental Eye Movement (DEM) test score (ratio, errors) taken before, midway, and immediately following training. For the DEM ratio parameter, improvements were found in 80-89% of the subjects. For the DEM error parameter, improvements were found in 100% of the subjects. Incorporation of the auditory feedback component revealed a trend toward enhanced performance. The findings were similar for both DEM parameters, as well as for incorporation of the auditory feedback, in both diagnostic groups. The results of the present study demonstrated considerable improvements in the DEM test scores following the oculomotor-based training, thus reflecting more time-optimal and accurate saccadic tracking after the training. The DEM test should be considered as another clinical test of global saccadic tracking performance in the ABI population. Copyright © 2017 Spanish General Council of Optometry. All rights reserved.

  14. A new DEM of the Austfonna ice cap by combining differential SAR interferometry with ICESat laser altimetry

    Directory of Open Access Journals (Sweden)

    Geir Moholdt

    2012-05-01

    Full Text Available We present a new digital elevation model (DEM of the Austfonna ice cap in the Svalbard Archipelago, Norwegian Arctic. Previous DEMs derived from synthetic aperture radar (SAR and optical shape-from-shading have been tied to airborne radio echo-sounding surface profiles from 1983 which contain an elevation-dependent bias of up to several tens of metres compared with recent elevation data. The new and freely available DEM is constructed purely from spaceborne remote sensing data using differential SAR interferometry (DInSAR in combination with ICESat laser altimetry. Interferograms were generated from pairs of SAR scenes from the one-day repeat tandem phase of the European Remote Sensing Satellites 1/2 (ERS-1/2 in 1996. ICESat elevations from winter 2006–08 were used as ground control points to refine the interferometric baseline. The resulting DEM is validated against the same ground control points and independent surface elevation profiles from Global Navigation Satellite Systems (GNSS and airborne laser altimetry, yielding root mean square (RMS errors of about 10 m in all cases. This quality is sufficient for most glaciological applications, and the new DEM will be a baseline data set for ongoing and future research at Austfonna. The technique of combining satellite DInSAR with high-resolution satellite altimetry for DEM generation might also be a good solution in other glacier regions with similar characteristics, especially when data from TanDEM-X and CryoSat-2 become available.

  15. Integration of 2-D hydraulic model and high-resolution lidar-derived DEM for floodplain flow modeling

    Science.gov (United States)

    Shen, D.; Wang, J.; Cheng, X.; Rui, Y.; Ye, S.

    2015-08-01

    The rapid progress of lidar technology has made the acquirement and application of high-resolution digital elevation model (DEM) data increasingly popular, especially in regards to the study of floodplain flow. However, high-resolution DEM data pose several disadvantages for floodplain modeling studies; e.g., the data sets contain many redundant interpolation points, large numbers of calculations are required to work with data, and the data do not match the size of the computational mesh. Two-dimensional (2-D) hydraulic modeling, which is a popular method for analyzing floodplain flow, offers highly precise elevation parameterization for computational mesh while ignoring much of the micro-topographic information of the DEM data itself. We offer a flood simulation method that integrates 2-D hydraulic model results and high-resolution DEM data, thus enabling the calculation of flood water levels in DEM grid cells through local inverse distance-weighted interpolation. To get rid of the false inundation areas during interpolation, it employs the run-length encoding method to mark the inundated DEM grid cells and determine the real inundation areas through the run-length boundary tracing technique, which solves the complicated problem of connectivity between DEM grid cells. We constructed a 2-D hydraulic model for the Gongshuangcha detention basin, which is a flood storage area of Dongting Lake in China, by using our integrated method to simulate the floodplain flow. The results demonstrate that this method can solve DEM associated problems efficiently and simulate flooding processes with greater accuracy than simulations only with DEM.

  16. Demência na população de pacientes do Hospital das Clínicas da Unicamp

    OpenAIRE

    Silva David W.; Damasceno Benito P

    2002-01-01

    OBJETIVO: Descrever subtipos de demência em pacientes atendidos no HC-UNICAMP. METODO: No período 1989-1998, foram admitidos 261 pacientes com demência (89,7% estudados retrospectivamente, e 10,3% prospectivamente); idade 63,5 anos (±13,2) e educação 3,6 anos (±3,9; 25% analfabetos). O diagnóstico de demência e seus subtipos baseou-se no DSM-IV, CAMDEX, NINCDS-ADRDA, NINDS-AIREN/ADDTC, Lund-Manchester, tap-teste liquórico, exames laboratoriais e de neuroimagem. RESULTADOS: Sesse...

  17. Doppler Centroid Estimation for Airborne SAR Supported by POS and DEM

    Directory of Open Access Journals (Sweden)

    CHENG Chunquan

    2015-05-01

    Full Text Available It is difficult to estimate the Doppler frequency and modulating rate for airborne SAR by using traditional vector method due to instable flight and complex terrain. In this paper, it is qualitatively analyzed that the impacts of POS, DEM and their errors on airborne SAR Doppler parameters. Then an innovative vector method is presented based on the range-coplanarity equation to estimate the Doppler centroid taking the POS and DEM as auxiliary data. The effectiveness of the proposed method is validated and analyzed via the simulation experiments. The theoretical analysis and experimental results show that the method can be used to estimate the Doppler centroid with high accuracy even in the cases of high relief, instable flight, and large squint SAR.

  18. Micromechanics of non-active clays in saturated state and DEM modelling

    Directory of Open Access Journals (Sweden)

    Pagano Arianna Gea

    2017-01-01

    Full Text Available The paper presents a conceptual micromechanical model for 1-D compression behaviour of non-active clays in saturated state. An experimental investigation was carried out on kaolin clay samples saturated with fluids of different pH and dielectric permittivity. The effect of pore fluid characteristics on one-dimensional compressibility behaviour of kaolin was investigated. A three dimensional Discrete Element Method (DEM was implemented in order to simulate the response of saturated kaolin observed during the experiments. A complex contact model was introduced, considering both the mechanical and physico-chemical microscopic interactions between clay particles. A simple analysis with spherical particles only was performed as a preliminary step in the DEM study in the elastic regime.

  19. An advanced distributed automated extraction of drainage network model on high-resolution DEM

    Directory of Open Access Journals (Sweden)

    Y. Mao

    2014-07-01

    distributed automated extraction of drainage network model (Adam was proposed in the study. The Adam model has two features: (1 searching upward from outlet of basin instead of sink filling, (2 dividing sub-basins on low-resolution DEM, and then extracting drainage network on sub-basins of high-resolution DEM. The case study used elevation data of the Shuttle Radar Topography Mission (SRTM at 3 arc-second resolution in Zhujiang River basin, China. The results show Adam model can dramatically reduce the computation time. The extracting drainage network was continuous and more accurate than HydroSHEDS (Hydrological data and maps based on Shuttle Elevation Derivatives at multiple Scales.

  20. A hybrid FEM-DEM approach to the simulation of fluid flow laden with many particles

    Science.gov (United States)

    Casagrande, Marcus V. S.; Alves, José L. D.; Silva, Carlos E.; Alves, Fábio T.; Elias, Renato N.; Coutinho, Alvaro L. G. A.

    2017-04-01

    In this work we address a contribution to the study of particle laden fluid flows in scales smaller than TFM (two-fluid models). The hybrid model is based on a Lagrangian-Eulerian approach. A Lagrangian description is used for the particle system employing the discrete element method (DEM), while a fixed Eulerian mesh is used for the fluid phase modeled by the finite element method (FEM). The resulting coupled DEM-FEM model is integrated in time with a subcycling scheme. The aforementioned scheme is applied in the simulation of a seabed current to analyze which mechanisms lead to the emergence of bedload transport and sediment suspension, and also quantify the effective viscosity of the seabed in comparison with the ideal no-slip wall condition. A simulation of a salt plume falling in a fluid column is performed, comparing the main characteristics of the system with an experiment.

  1. GPS based checking survey and precise DEM development in Open mine

    Institute of Scientific and Technical Information of China (English)

    XU Ai-gong

    2008-01-01

    The checking survey in Open mine is one of the most frequent and important work. It plays the role of forming a connecting link between open mine planning and production. Traditional checking method has such disadvantages as long time consumption,heavy workload, complicated calculating process, and lower automation. Used GPS and GIS technologies to systematically study the core issues of checking survey in open mine.A detail GPS data acquisition coding scheme was presented. Based on the scheme an algorithm used for computer semiautomatic cartography was made. Three methods used for eliminating gross errors from raw data which were needed for creating DEM was discussed. Two algorithms were researched and realized which can be used to create open mine fine DEM model with constrained conditions and to dynamically update the model.The precision analysis and evaluation of the created model were carried out.

  2. Implementing a global DEM database on the sphere based on spherical wavelets

    Science.gov (United States)

    Zhao, Di; Zhao, Xuesheng; Shan, Shigang; Yao, Liangjun

    2010-11-01

    Wavelets have been proven to be an exceedingly powerful and highly efficient tool for fast computational algorithms in the fields of image data analysis and compression. Traditionally, the classical constructed wavelets are often employed to Euclidean infinite domains (such as the real line R and plane R2). In this paper, a spherical wavelet constructed for discrete DEM data based on the sphere is approached. Firstly, the discrete biorthogonal spherical wavelet with custom properties is constructed with the lifting scheme based on wavelet toolbox in Matlab. Then, the decomposition and reconstruction algorithms are proposed for efficient computation and the related wavelet coefficients are obtained. Finally, different precise images are displayed and analyzed at the different percentage of wavelet coefficients. The efficiency of this spherical wavelet algorithm is tested by using the GTOPO30 DEM data and the results show that at the same precision, the spherical wavelet algorithm consumes smaller storage volume. The results are good and acceptable.

  3. Análisis DEM 3D de arcos en regiones activas solares

    Science.gov (United States)

    Nuevo, F. A.; Mandrini, C. H.; Vásquez, A. M.; López Fuentes, M.

    2016-08-01

    The solar corona is highly organized by the magnetic field. Because of their temperature and density, magnetic loops are directly observable in active regions (ARs) in the extreme ultraviolet (EUV) and soft X-ray images. The observational determination of the three-dimensional (3D) distribution of basic physical parameters (electronic density and temperature, and magnetic field) is a fundamental constraint of coronal heating models. In this work we develop a technique of differential emission measure (DEM) analysis and we apply it an EUV loop identified in the images of the Atmospheric Imaging Assembly (AIA) on board the Solar Dynamics Observatory (SDO). The DEM is determined after background subtraction and the electronic density and temperature in the loop are estimated from its moments. The 3D structure of the magnetic field in the loop and its intensity are modeled using linear force free field extrapolations based on AR magnetograms. In this work we show preliminary results of this technique.

  4. Coupled DEM-CFD Investigation of Granular Transport in a Fluid Channel

    Science.gov (United States)

    Zhao, T.; Dai, F.; Xu, N. W.

    2015-09-01

    This paper presents three dimensional numerical investigations of granular transport in fluids, analysed by the Discrete Element Method (DEM) coupled with Computational Fluid Mechanics (CFD). By employing this model, the relevance of flow velocity and granular depositional morphology has been clarified. The larger the flow velocity is, the further distance the grains can be transported to. In this process, the segregation of solid grains has been clearly identified. This research reveals that coarse grains normally accumulate near the grain source region, while the fine grains can be transported to the flow front. Regardless of the different flow velocities used in these simulations, the intensity of grains segregation remains almost unchanged. The results obtained from the DEM-CFD coupled simulations can reasonably explain the grain transport process occurred in natural environments, such as river scouring, evolution of river/ocean floor, deserts and submarine landslides.

  5. DEM extraction and its accuracy analysis with ground-based SAR interferometry

    Science.gov (United States)

    Dong, J.; Yue, J. P.; Li, L. H.

    2014-03-01

    Two altimetry models extracting DEM (Digital Elevation Model) with the GBSAR (Ground-Based Synthetic Aperture Radar) technology are studied and their accuracies are analyzed in detail. The approximate and improved altimetry models of GBSAR were derived from the spaceborne radar altimetry based on the principles of the GBSAR technology. The error caused by the parallel ray approximation in the approximate model was analyzed quantitatively, and the results show that the errors cannot be ignored for the ground-based radar system. For the improved altimetry model, the elevation error expression can be acquired by simulating and analyzing the error propagation coefficients of baseline length, wavelength, differential phase and range distance in the mathematical model. By analyzing the elevation error with the baseline and range distance, the results show that the improved altimetry model is suitable for high-precision DEM and the accuracy can be improved by adjusting baseline and shortening slant distance.

  6. Digital Elevation Model (DEM), LiDAR-based Digital Elevation Model (DEM) in Esri GRID format. 5 foot resolution countywide., Published in 2010, 1:1200 (1in=100ft) scale, Brown County, WI.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Digital Elevation Model (DEM) dataset, published at 1:1200 (1in=100ft) scale, was produced all or in part from LIDAR information as of 2010. It is described as...

  7. Digital Elevation Model (DEM), 20' Grid DEM for Iredell County provided by 2003 Floodplain Mapping Program data, Published in 2007, 1:600 (1in=50ft) scale, Iredell County GIS.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Digital Elevation Model (DEM) dataset, published at 1:600 (1in=50ft) scale, was produced all or in part from LIDAR information as of 2007. It is described as...

  8. Digital Elevation Model (DEM), The OSIP 2.5FT gridded DEM was derived from LiDAR, Published in 2007, 1:600 (1in=50ft) scale, Ohio Geographically Referenced Information Program (OGRIP).

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Digital Elevation Model (DEM) dataset, published at 1:600 (1in=50ft) scale, was produced all or in part from LIDAR information as of 2007. It is described as...

  9. Digital Elevation Model (DEM), 5-ft dem derived from LIDAR point data. Some errors between mosaiced tile edges., Published in 2006, 1:600 (1in=50ft) scale, Lumpkin County, GA.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Digital Elevation Model (DEM) dataset, published at 1:600 (1in=50ft) scale, was produced all or in part from LIDAR information as of 2006. It is described as...

  10. Application Research of DEMs-STP Mixture Model in 3D Stratum Modeling%DEMs-STP混合模型在三维地层建模中的应用研究

    Institute of Scientific and Technical Information of China (English)

    衣昕; 贾瑞生

    2012-01-01

    本文提出了一个多层DEM(Digital Elevation Model,DEM)及似三棱柱(Similar Tri-Prism,STP)混合的三维地层模型DEMs-STP,该模型使用多层DEM构建地表及地质分层界面,使用STP构造层间地质体,改进了STP的切割处理,并利用IDL作为开发工具,实现了三维可视化.实验结果表明,DEMs-STP混合数据模型具有同时表示空间对象表面和内部结构的能力,适合地质勘探领域的三维建模.

  11. Digital Elevation Model (DEM), 10' DEM from LIDAR (1.2 m raw point spacing, 36.6 cm vertical accuracy, 50 cm horizontal), Published in 2008, 1:1200 (1in=100ft) scale, CITY OF PORTAGE.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Digital Elevation Model (DEM) dataset, published at 1:1200 (1in=100ft) scale, was produced all or in part from LIDAR information as of 2008. It is described as...

  12. Digital Elevation Model (DEM), DEM created from LIDAR data collected in the spring of 2009 as part of an MPO aerial/contour collection., Published in 2009, 1:600 (1in=50ft) scale, City of Bismarck.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Digital Elevation Model (DEM) dataset, published at 1:600 (1in=50ft) scale, was produced all or in part from LIDAR information as of 2009. It is described as...

  13. Tropical-Forest Biomass Dynamics from X-Band, TanDEM-X DATA

    Science.gov (United States)

    Treuhaft, R. N.; Neumann, M.; Keller, M. M.; Goncalves, F. G.; Santos, J. R.

    2015-12-01

    The measurement of the change in above ground biomass (AGB) is key for understanding the carbon sink/source nature of tropical forests. Interferometric X-band radar from the only orbiting interferometer, TanDEM-X, shows sensitivity to standing biomass up to at least 300 Mg/ha. This sensitivity may be due in part to the propagation of the shorter X-band wavelength (0.031 m) through holes in the canopy. This talk focuses on estimating the change in AGB over time. Interferometric baselines from TanDEM-X have been obtained in Tapajós National Forest in the Brazilian Amazon over a 4-year period, from 2011 to 2015. Lidar measurements were also acquired during this period. Field measurements of height, height-to-base-of-crown, species, diameter, and position were acquired in 2010, 2013, and 2015. We show interferometric phase height changes, and suggest how these phase height changes are related to biomass change. First we show height changes between baselines separated by one month, over which we expect no change in AGB, to evaluate precision. We find an RMS of 3 m, due to actual change. Most stands show changes in interferometric phase height consistent with regrowth (~10 Mg/ha/yr), and several stands show abrupt, large changes in phase height (>10 m) due to logging and natural disturbance. At the end of 2015, we will acquire more TanDEM-X data over Tapajos, including an area subjected to selective logging. We are doing "before" (March 2015) and "after" (October 2015) fieldwork to be able to understand the signature of change due to selective logging in TanDEM-X interferometric data.

  14. Ein Arachniden-Opisthosoma aus dem Obervisé von NW-Sachsen

    Directory of Open Access Journals (Sweden)

    E. Kahlert

    1998-01-01

    Full Text Available Ein aus dem Unterkarbon von NW-Sachsen stammendes Opisthosoma wird als Cryptomartus sp. beschrieben. Damit liegt stratigraphisch nach bisherigen Erkenntnissen der älteste Fund dieses Genus vor. An Arachnid-Opisthosoma from the Lower Carboniferous of North Western Saxony. An opisthosoma of Cryptomartus sp. is described from the Lower Carboniferous of North Western Saxony. That this my knowledge is the oldest record for the genus. doi:10.1002/mmng.19980010109

  15. Simultandolmetschen aus dem Deutschen : warten auf das Verb? Ein altes Thema aus neuer Sicht

    DEFF Research Database (Denmark)

    Dubslaff, Friedel

    1997-01-01

    I artiklen fremstilles resultaterne af en empirisk undersøgelse af spørgsmålet om, hvad informanter gør, når de ved simultantolkning fra tysk til dansk ikke ønsker at vente på verbet i den udgangssproglige ytring. Undersøgelsens informanter bruger en genoptagelsesteknik, som bl. a. sætter dem i s...

  16. a Hadoop-Based Algorithm of Generating dem Grid from Point Cloud Data

    Science.gov (United States)

    Jian, X.; Xiao, X.; Chengfang, H.; Zhizhong, Z.; Zhaohui, W.; Dengzhong, Z.

    2015-04-01

    Airborne LiDAR technology has proven to be the most powerful tools to obtain high-density, high-accuracy and significantly detailed surface information of terrain and surface objects within a short time, and from which the Digital Elevation Model of high quality can be extracted. Point cloud data generated from the pre-processed data should be classified by segmentation algorithms, so as to differ the terrain points from disorganized points, then followed by a procedure of interpolating the selected points to turn points into DEM data. The whole procedure takes a long time and huge computing resource due to high-density, that is concentrated on by a number of researches. Hadoop is a distributed system infrastructure developed by the Apache Foundation, which contains a highly fault-tolerant distributed file system (HDFS) with high transmission rate and a parallel programming model (Map/Reduce). Such a framework is appropriate for DEM generation algorithms to improve efficiency. Point cloud data of Dongting Lake acquired by Riegl LMS-Q680i laser scanner was utilized as the original data to generate DEM by a Hadoop-based algorithms implemented in Linux, then followed by another traditional procedure programmed by C++ as the comparative experiment. Then the algorithm's efficiency, coding complexity, and performance-cost ratio were discussed for the comparison. The results demonstrate that the algorithm's speed depends on size of point set and density of DEM grid, and the non-Hadoop implementation can achieve a high performance when memory is big enough, but the multiple Hadoop implementation can achieve a higher performance-cost ratio, while point set is of vast quantities on the other hand.

  17. CFD-DEM Onset of Motion Analysis for Application to Bed Scour Risk Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Sitek, M. A. [Argonne National Lab. (ANL), Argonne, IL (United States); Lottes, S. A. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2017-03-01

    This CFD study with DEM was done as a part of the Federal Highway Administration’s (FHWA’s) effort to improve scour design procedures. The Computational Fluid Dynamics-Discrete Element Method (CFD-DEM) model, available in CD-Adapco’s StarCCM+ software, was used to simulate multiphase systems, mainly those which combine fluids and solids. In this method the motion of discrete solids is accounted for by DEM, which applies Newton's laws of motion to every particle. The flow of the fluid is determined by the local averaged Navier–Stokes equations that can be solved using the traditional CFD approach. The interactions between the fluid phase and solids phase are modeled by use of Newton's third law. The inter-particle contact forces are included in the equations of motion. Soft-particle formulation is used, which allows particles to overlap. In this study DEM was used to model separate sediment grains and spherical particles laying on the bed with the aim to analyze their movement due to flow conditions. Critical shear stress causing the incipient movement of the sediment was established and compared to the available experimental data. An example of scour around a cylindrical pier is considered. Various depths of the scoured bed and flow conditions were taken into account to gain a better understanding of the erosion forces existing around bridge foundations. The decay of these forces with increasing scour depth was quantified with a ‘decay function’, which shows that particles become increasingly less likely to be set in motion by flow forces as a scour hole increases in depth. Computational and experimental examples of the scoured bed around a cylindrical pier are presented.

  18. Fitra und Fides - Glaubensvergewisserung und Alterität im muslimischen Dialog mit dem Christentum

    OpenAIRE

    Braun, Rüdiger

    2009-01-01

    Ausgehend von der grundlegenden These eines unlösbaren Zusammenhangs zwischen Alteritätsdenken einerseits und der Verhältnisbestimmung von Geschöpflichkeit und Glaube andererseits versucht die vorliegende Untersuchung, anhand einer Darstellung der Grundlinien des gegenwärtigen, auf Paradigmen des sunnitischen Islam beschränkten muslimischen Alteritätsdiskurses den Referenzrahmen zu markieren, in dem der christlich-muslimische Dialog islamischerseits verortet wird. Dazu arbeitet Abschnitt I (G...

  19. A 'Drift' algorithm for integrating vector polyline and DEM based on the spherical DQG

    Science.gov (United States)

    Wang, Jiaojiao; Wang, Lei; Cao, Wenmin; Zhao, Xuesheng

    2014-03-01

    The efficient integration method of vector and DEM data on a global scale is one of the important issues in the community of Digital Earth. Among the existing methods, geometry-based approach maintains the characteristics of vector data necessary for inquiry and analysis. However, the complexity of geometry-based approach, which needs lots of interpolation calculation, limits its applications greatly in the multi-source spatial data integration on a global scale. To overcome this serious deficiency, a novel 'drift' algorithm is developed based on the spherical Degenerate Quadtree Grid (DQG) on which the global DEMs data is represented. The main principle of this algorithm is that the vector node in a DQG cell can be moved to the cell corner-point without changing the visualization effects if the cell is smaller or equal to a pixel of screen. A detailed algorithm and the multi-scale operation steps are also presented. By the 'drift' algorithm, the vector polylines and DEM grids are integrated seamlessly, avoiding lots of interpolation calculating. Based on the approach described above, we have developed a computer program in platform OpenGL 3D API with VC++ language. In this experiment, USGS GTOPO30 DEM data and 1:1,000,000 DCW roads data sets in China area are selected. Tests have shown that time consumption of the 'drift' algorithm is only about 25% of that of the traditional ones, moreover, the mean error of drift operation on vector nodes can be controlled within about half a DQG cell. In the end, the conclusions and future works are also given.

  20. Aster Global dem Version 3, and New Aster Water Body Dataset

    Science.gov (United States)

    Abrams, M.

    2016-06-01

    In 2016, the US/Japan ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer) project released Version 3 of the Global DEM (GDEM). This 30 m DEM covers the earth's surface from 82N to 82S, and improves on two earlier versions by correcting some artefacts and filling in areas of missing DEMs by the acquisition of additional data. The GDEM was produced by stereocorrelation of 2 million ASTER scenes and operation on a pixel-by-pixel basis: cloud screening; stacking data from overlapping scenes; removing outlier values, and averaging elevation values. As previously, the GDEM is packaged in ~ 23,000 1 x 1 degree tiles. Each tile has a DEM file, and a NUM file reporting the number of scenes used for each pixel, and identifying the source for fill-in data (where persistent clouds prevented computation of an elevation value). An additional data set was concurrently produced and released: the ASTER Water Body Dataset (AWBD). This is a 30 m raster product, which encodes every pixel as either lake, river, or ocean; thus providing a global inland and shore-line water body mask. Water was identified through spectral analysis algorithms and manual editing. This product was evaluated against the Shuttle Water Body Dataset (SWBD), and the Landsat-based Global Inland Water (GIW) product. The SWBD only covers the earth between about 60 degrees north and south, so it is not a global product. The GIW only delineates inland water bodies, and does not deal with ocean coastlines. All products are at 30 m postings.

  1. Der vergessene Wanderstock: ein Fundstück aus dem Nachlass von Franz Pöggeler

    OpenAIRE

    Heuer, Klaus

    2011-01-01

    Der Beitrag stellt ein Objekt aus dem historischen Archiv des Deutschen Instituts für Erwachsenenbildung vor, ein Wanderstock, der mit Robert von Erdberg, Walter Hofmann und Rudolf Reuter unter Protagonisten des "Hohenrodter Bundes" weitergegeben worden ist und über den Nachlass von Franz Pöggeler aufgefunden wurde. Anhand der Weitergabe dieses Objekts lassen sich Kontinuitäten in der Geschichte der Erwachsenenbildung nachzeichnen.

  2. Fluid-particle flow and validation using two-way-coupled mesoscale SPH-DEM

    OpenAIRE

    Robinson, Martin; Luding, Stefan; Ramaioli, Marco

    2013-01-01

    First, a meshless simulation method is presented for multiphase fluid-particle flows with a two-way coupled Smoothed Particle Hydrodynamics (SPH) for the fluid and the Discrete Element Method (DEM) for the solid phase. The unresolved fluid model, based on the locally averaged Navier Stokes equations, is expected to be considerably faster than fully resolved models. Furthermore, in contrast to similar mesh-based Discrete Particle Methods (DPMs), our purely particle-based method enjoys the flex...

  3. On some spectral properties of TanDEM-X interferograms over forested areas

    OpenAIRE

    De Zan, Francesco; Krieger, Gerhard; López-Dekker, Paco

    2013-01-01

    This letter reports about some obervations over rainforest (in Brazil and Indonesia), where the spectra of TanDEM-X interferograms show distinct features, almost a signature, which is explained and modelled in terms of the scattering properties. Supported by comparisons with simulations, the observations exclude any homogeneous, horizontally-layered forest; instead, they are compatible with a model with point scatterers clustered in clouds. Such a model, with high extinction and large gaps...

  4. Observations and discussions of TanDEM-X interferogram spectra over rain forest

    OpenAIRE

    De Zan, Francesco; Krieger, Gerhard; López-Dekker, Paco

    2012-01-01

    This paper reports about some obervations over rainforest (in Brazil and Indonesia), where the spectra of TanDEM-X interferograms show distinct features, almost a signature, which is explained and modelled in terms of the scattering properties. Thanks to the comparison with simulations, the observations exclude a homogeneous, horizontally-layered forest; instead, they are compatible with a model with point scatterers clustered in clouds. Such a model, with high extinction and large gaps th...

  5. Simultandolmetschen aus dem Deutschen : warten auf das Verb? Ein altes Thema aus neuer Sicht

    DEFF Research Database (Denmark)

    Dubslaff, Friedel

    1997-01-01

    I artiklen fremstilles resultaterne af en empirisk undersøgelse af spørgsmålet om, hvad informanter gør, når de ved simultantolkning fra tysk til dansk ikke ønsker at vente på verbet i den udgangssproglige ytring. Undersøgelsens informanter bruger en genoptagelsesteknik, som bl. a. sætter dem i s...

  6. A time series of TanDEM-X digital elevation models to monitor a glacier surge

    Science.gov (United States)

    Wendt, Anja; Mayer, Christoph; Lambrecht, Astrid; Floricioiu, Dana

    2016-04-01

    Bivachny Glacier, a tributary of the more than 70 km long Fedchenko Glacier in the Pamir Mountains, Central Asia, is a surge-type glacier with three known surges during the 20th century. In 2011, the most recent surge started which, in contrast to the previous ones, evolved down the whole glacier and reached the confluence with Fedchenko Glacier. Spatial and temporal glacier volume changes can be derived from high-resolution digital elevation models (DEMs) based on bistatic InSAR data from the TanDEM-X mission. There are nine DEMs available between 2011 and 2015 covering the entire surge period in time steps from few months up to one year. During the surge, the glacier surface elevation increased by up to 130 m in the lower part of the glacier; and change rates of up to 0.6 m per day were observed. The surface height dataset was complemented with glacier surface velocity information from TerraSAR-X/ TanDEM-X data as well as optical Landsat imagery. While the glacier was practically stagnant in 2000 after the end of the previous surge in the 1990s, the velocity increase started in 2011 in the upper reaches of the ablation area and successively moved downwards and intensified, reaching up to 4.0 m per day. The combination of surface elevation changes and glacier velocities, both of high temporal and spatial resolution, provides the unique opportunity to describe and analyse the evolution of the surge in unprecedented detail. Especially the relation between the mobilization front and the local mass transport provides insight into the surge dynamics.

  7. APPLICATION OF LIDAR-DERIVED DEM FOR DETECTION OF MASS MOVEMENTS ON A LANDSLIDE

    Directory of Open Access Journals (Sweden)

    M. Barbarella

    2014-01-01

    Full Text Available In order to reliably detect changes in the surficial morphology of a landslide, measurements performed at the different epochs being compared have to comply with certain characteristics such as allowing the reconstruction of the surface from acquired points and a resolution sufficiently high to provide a proper description of details. Terrestrial Laser Scanning survey enables to acquire large amounts of data and therefore potentially allows knowing even small details of a landslide. By appropriate additional field measurements, point clouds can be referenced to a common reference system with high accuracy, so that scans effectively share the same system. In this note we present the monitoring of a large landslide by two surveys carried out two years apart from each other. The adopted reference frame consists of a network of GNSS (Global Navigation Satellite Systems permanent stations that constitutes a system of controlled stability over time. Knowledge of the shape of the surface comes from the generation of a DEM (Digital Elevation Model. Some algorithms are compared and the analysis is performed by means of the evaluation of some statistical parameters using cross-validation. In general, evaluation of mass displacements occurred between two surveys is possible differencing the corresponding DEMs, but then arises the need to distinguish the different behaviors of the various landslide bodies that could be present among the slope. Here landslide bodies' identification has been carried out considering geomorphological criteria, making also use of DEM derived products, such as contour maps, slope and aspect maps.

  8. A Review of Discrete Element Method (DEM) Particle Shapes and Size Distributions for Lunar Soil

    Science.gov (United States)

    Lane, John E.; Metzger, Philip T.; Wilkinson, R. Allen

    2010-01-01

    As part of ongoing efforts to develop models of lunar soil mechanics, this report reviews two topics that are important to discrete element method (DEM) modeling the behavior of soils (such as lunar soils): (1) methods of modeling particle shapes and (2) analytical representations of particle size distribution. The choice of particle shape complexity is driven primarily by opposing tradeoffs with total number of particles, computer memory, and total simulation computer processing time. The choice is also dependent on available DEM software capabilities. For example, PFC2D/PFC3D and EDEM support clustering of spheres; MIMES incorporates superquadric particle shapes; and BLOKS3D provides polyhedra shapes. Most commercial and custom DEM software supports some type of complex particle shape beyond the standard sphere. Convex polyhedra, clusters of spheres and single parametric particle shapes such as the ellipsoid, polyellipsoid, and superquadric, are all motivated by the desire to introduce asymmetry into the particle shape, as well as edges and corners, in order to better simulate actual granular particle shapes and behavior. An empirical particle size distribution (PSD) formula is shown to fit desert sand data from Bagnold. Particle size data of JSC-1a obtained from a fine particle analyzer at the NASA Kennedy Space Center is also fitted to a similar empirical PSD function.

  9. DEM Modelling of Granule Rearrangement and Fracture Behaviours During a Closed-Die Compaction.

    Science.gov (United States)

    Furukawa, Ryoichi; Kadota, Kazunori; Noguchi, Tetsuro; Shimosaka, Atsuko; Shirakawa, Yoshiyuki

    2017-01-26

    The closed-die compaction behaviour of D-mannitol granules has been simulated by the discrete element method (DEM) to investigate the granule rearrangement and fracture behaviour during compaction which affects the compactibility of the tablet. The D-mannitol granules produced in a fluidized bed were modelled as agglomerates of primary particles connected by linear spring bonds. The validity of the model granule used in the DEM simulation was demonstrated by comparing to the experimental results of a uniaxial compression test. During uniaxial compression, the numerical results of the force-displacement curve corresponded reasonably well to the experimental data. The closed-die compaction of the modelled granules was carried out to investigate the rearrangement and fracture behaviours of the granule at different upper platen velocities. The forces during closed-die compaction calculated by DEM fluctuated in the low-pressure region due to the rearrangement of granules. A Heckel analysis showed that the force fluctuation occurred at the initial bending region of the Heckel plot, which represents the granule rearrangement and fracture. Furthermore, the upper platen velocity affected the trend of compaction forces, which can lead to compaction failure due to capping. These results could contribute to designing the appropriate granules during closed-die compaction.

  10. Fluid-particle flow modelling and validation using two-way-coupled mesoscale SPH-DEM

    CERN Document Server

    Robinson, Martin; Ramaioli, Marco

    2013-01-01

    We present a meshless simulation method for multiphase fluid-particle flows coupling Smoothed Particle Hydrodynamics (SPH) and the Discrete Element Method (DEM). Rather than fully resolving the interstitial fluid, which is often infeasible, the unresolved fluid model is based on the locally averaged Navier Stokes equations, which are coupled with a DEM model for the solid phase. In contrast to similar mesh-based Discrete Particle Methods (DPMs), this is a purely particle-based method and enjoys the flexibility that comes from the lack of a prescribed mesh. It is suitable for problems such as free surface flow or flow around complex, moving and/or intermeshed geometries. It can be used for both one and two-way coupling and is applicable to both dilute and dense particle flows. A comprehensive validation procedure for fluid-particle simulations is presented and applied to the SPH-DEM method, using simulations of single and multiple particle sedimentation in a 3D fluid column and comparison with analytical model...

  11. Calibration of DEM parameters on shear test experiments using Kriging method

    Science.gov (United States)

    Xavier, Bednarek; Sylvain, Martin; Abibatou, Ndiaye; Véronique, Peres; Olivier, Bonnefoy

    2017-06-01

    Calibration of powder mixing simulation using Discrete-Element-Method is still an issue. Achieving good agreement with experimental results is difficult because time-efficient use of DEM involves strong assumptions. This work presents a methodology to calibrate DEM parameters using Efficient Global Optimization (EGO) algorithm based on Kriging interpolation method. Classical shear test experiments are used as calibration experiments. The calibration is made on two parameters - Young modulus and friction coefficient. The determination of the minimal number of grains that has to be used is a critical step. Simulations of a too small amount of grains would indeed not represent the realistic behavior of powder when using huge amout of grains will be strongly time consuming. The optimization goal is the minimization of the objective function which is the distance between simulated and measured behaviors. The EGO algorithm uses the maximization of the Expected Improvement criterion to find next point that has to be simulated. This stochastic criterion handles with the two interpolations made by the Kriging method : prediction of the objective function and estimation of the error made. It is thus able to quantify the improvement in the minimization that new simulations at specified DEM parameters would lead to.

  12. Fusion of Laser Altimetry Data with Dems Derived from Stereo Imaging Systems

    Science.gov (United States)

    Schenk, T.; Csatho, B. M.; Duncan, K.

    2016-06-01

    During the last two decades surface elevation data have been gathered over the Greenland Ice Sheet (GrIS) from a variety of different sensors including spaceborne and airborne laser altimetry, such as NASA's Ice Cloud and land Elevation Satellite (ICESat), Airborne Topographic Mapper (ATM) and Laser Vegetation Imaging Sensor (LVIS), as well as from stereo satellite imaging systems, most notably from Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) and Worldview. The spatio-temporal resolution, the accuracy, and the spatial coverage of all these data differ widely. For example, laser altimetry systems are much more accurate than DEMs derived by correlation from imaging systems. On the other hand, DEMs usually have a superior spatial resolution and extended spatial coverage. We present in this paper an overview of the SERAC (Surface Elevation Reconstruction And Change detection) system, designed to cope with the data complexity and the computation of elevation change histories. SERAC simultaneously determines the ice sheet surface shape and the time-series of elevation changes for surface patches whose size depends on the ruggedness of the surface and the point distribution of the sensors involved. By incorporating different sensors, SERAC is a true fusion system that generates the best plausible result (time series of elevation changes) a result that is better than the sum of its individual parts. We follow this up with an example of the Helmheim gacier, involving ICESat, ATM and LVIS laser altimetry data, together with ASTER DEMs.

  13. Pre-2014 mudslides at Oso revealed by InSAR and multi-source DEM analysis

    Science.gov (United States)

    Kim, J. W.; Lu, Z.; QU, F.

    2014-12-01

    The landslide is a process that results in the downward and outward movement of slope-reshaping materials including rocks and soils and annually causes the loss of approximately $3.5 billion and tens of casualties in the United States. The 2014 Oso mudslide was an extreme event costing nearly 40 deaths and damaging civilian properties. Landslides are often unpredictable, but in many cases, catastrophic events are repetitive. Historic record in the Oso mudslide site indicates that there have been serial events in decades, though the extent of sliding events varied from time to time. In our study, the combination of multi-source DEMs, InSAR, and time-series InSAR analysis has enabled to characterize the Oso mudslide. InSAR results from ALOS PALSAR show that there was no significant deformation between mid-2006 and 2011. The combination of time-series InSAR analysis and old-dated DEM indicated revealed topographic changes associated the 2006 sliding event, which is confirmed by the difference of multiple LiDAR DEMs. Precipitation and discharge measurements before the 2006 and 2014 landslide events did not exhibit extremely anomalous records, suggesting the precipitation is not the controlling factor in determining the sliding events at Oso. The lack of surface deformation during 2006-2011 and weak correlation between the precipitation and the sliding event, suggest other factors (such as porosity) might play a critical role on the run-away events at this Oso and other similar landslides.

  14. Tropical forest heterogeneity from TanDEM-X InSAR and lidar observations in Indonesia

    Science.gov (United States)

    De Grandi, Elsa Carla; Mitchard, Edward

    2016-10-01

    Fires exacerbated during El Niño Southern Oscillation are a serious threat in Indonesia leading to the destruction and degradation of tropical forests and emissions of CO2 in the atmosphere. Forest structural changes which occurred due to the 1997-1998 El Niño Southern Oscillation in the Sungai Wain Protection Forest (East Kalimantan, Indonesia), a previously intact forest reserve have led to the development of a range of landcover from secondary forest to areas dominated by grassland. These structural differences can be appreciated over large areas by remote sensing instruments such as TanDEM-X and LiDAR that provide information that are sensitive to vegetation vertical and horizontal structure. One-point statistics of TanDEM-X coherence (mean and CV) and LiDAR CHM (mean, CV) and derived metrics such as vegetation volume and canopy cover were tested for the discrimination between 4 landcover classes. Jeffries-Matusita (JM) separability was high between forest classes (primary or secondary forest) and non-forest (grassland) while, primary and secondary forest were not separable. The study tests the potential and the importance of potential of TanDEM-X coherence and LiDAR observations to characterize structural heterogeneity based on one-point statistics in tropical forest but requires improved characterization using two-point statistical measures.

  15. A Seamless, High-Resolution, Coastal Digital Elevation Model (DEM) for Southern California

    Science.gov (United States)

    Barnard, Patrick L.; Hoover, Daniel

    2010-01-01

    A seamless, 3-meter digital elevation model (DEM) was constructed for the entire Southern California coastal zone, extending 473 km from Point Conception to the Mexican border. The goal was to integrate the most recent, high-resolution datasets available (for example, Light Detection and Ranging (Lidar) topography, multibeam and single beam sonar bathymetry, and Interferometric Synthetic Aperture Radar (IfSAR) topography) into a continuous surface from at least the 20-m isobath to the 20-m elevation contour. This dataset was produced to provide critical boundary conditions (bathymetry and topography) for a modeling effort designed to predict the impacts of severe winter storms on the Southern California coast (Barnard and others, 2009). The hazards model, run in real-time or with prescribed scenarios, incorporates atmospheric information (wind and pressure fields) with a suite of state-of-the-art physical process models (tide, surge, and wave) to enable detailed prediction of water levels, run-up, wave heights, and currents. Research-grade predictions of coastal flooding, inundation, erosion, and cliff failure are also included. The DEM was constructed to define the general shape of nearshore, beach and cliff surfaces as accurately as possible, with less emphasis on the detailed variations in elevation inland of the coast and on bathymetry inside harbors. As a result this DEM should not be used for navigation purposes.

  16. Parametrisation of a DEM model for railway ballast under different load cases.

    Science.gov (United States)

    Suhr, Bettina; Six, Klaus

    2017-01-01

    The prediction quality of discrete element method (DEM) models for railway ballast can be expected to depend on three points: the geometry representation of the single particles, the used contact models and the parametrisation using principal experiments. This works aims at a balanced approach, where none of the points is addressed with excessive depth. In a first step, a simple geometry representation is chosen and the simplified Hertz-Mindlin contact model is used. When experimental data of cyclic compression tests and monotonic direct shear tests are considered, the model can be parametrised to fit either one of the two tests, but not both with the same set of parameters. Similar problems can be found in literature for monotonic and cyclic triaxial tests of railway ballast. In this work, the comparison between experiment and simulation is conducted using the entire data of the test, e.g. shear force over shear path curve from the direct shear test. In addition to a visual comparison of the results also quantitative errors based on the sum of squares are defined. To improve the fit of the DEM model to both types of experiments, an extension on the Hertz-Mindlin contact law is used, which introduces additional physical effects (e.g. breakage of edges or yielding). This model introduces two extra material parameters and is successfully parametrised. Using only one set of parameters, the results of the DEM simulation are in good accordance with both experimental cyclic compression test and monotonic directs shear test.

  17. Detection and evaluation on phosphorite mining environment contamination sources using ASTER and DEM

    Science.gov (United States)

    Chen, Wei-tao; Zhang, Zhi; Li, Zhi-zhong; Yang, Jun-jie; Qian, Li-ping

    2008-11-01

    The main environment contamination source of the phosphorite mining area, located in Huji city, Hubei province, China, was detected and evaluated using ASTER and DEM. Firstly, the featured spectrum that has unique diagnose spectral feature was generalized after analyzing the types and spectrum characteristics of the sample contamination source in the area. Secondly, the main contamination source of the area was recognized by means of principal component analysis using ASTER band 1-9. And the distributions of them were in accordance with that of phosphorite, carbonate and waste water. Finally, flow accumulation and catchment images were simulated using DEM and GIS. By analyzing the images of the flow accumulation, catchment and contamination source, the authors conclude that large scale opencast phosphorite mining and solid waste materials have damaged mining environment; the disordered piling of solid waste material has been boosting diffusion and migration of harmful and toxic matters; and all of these has damaged heavily ecological environment of lower reaches, and is the potential unsafe factor for that of Hanjiang river also. Keywords: ASTER, DEM, mining contamination, detection and evaluation on contamination sources 1.

  18. Dissipation consistent fabric tensor definition from DEM to continuum for granular media

    Science.gov (United States)

    Li, X. S.; Dafalias, Y. F.

    2015-05-01

    In elastoplastic soil models aimed at capturing the impact of fabric anisotropy, a necessary ingredient is a measure of anisotropic fabric in the form of an evolving tensor. While it is possible to formulate such a fabric tensor based on indirect phenomenological observations at the continuum level, it is more effective and insightful to have the tensor defined first based on direct particle level microstructural observations and subsequently deduce a corresponding continuum definition. A practical means able to provide such observations, at least in the context of fabric evolution mechanisms, is the discrete element method (DEM). Some DEM defined fabric tensors such as the one based on the statistics of interparticle contact normals have already gained widespread acceptance as a quantitative measure of fabric anisotropy among researchers of granular material behavior. On the other hand, a fabric tensor in continuum elastoplastic modeling has been treated as a tensor-valued internal variable whose evolution must be properly linked to physical dissipation. Accordingly, the adaptation of a DEM fabric tensor definition to a continuum constitutive modeling theory must be thermodynamically consistent in regards to dissipation mechanisms. The present paper addresses this issue in detail, brings up possible pitfalls if such consistency is violated and proposes remedies and guidelines for such adaptation within a recently developed Anisotropic Critical State Theory (ACST) for granular materials.

  19. KAJIAN PEMANFAATAN DEM SRTM & GOOGLE EARTH UNTUK PARAMETER PENILAIAN POTENSI KERUGIAN EKONOMI AKIBAT BANJIR ROB

    Directory of Open Access Journals (Sweden)

    Arief L Nugraha

    2013-12-01

    Full Text Available Tidal flood is a significant threat for the economic growth rate in the city of Semarang. The threat mitigation requires planning, thereby reducing the impact of the losses. The availability of global data with free access can provide solutions in disaster management, the data are SRTM DEM and Google Earth. With both of these data can be mapped potential economic losses caused by tidal flooding. With the techniques of remote sensing and GIS to handle the SRTM DEM data and Google Earth, the techniques can be generated maps and models of tidal inundation area maps woke up in the city of Semarang. Analysis of potential economic losses can be calculated by doing an overlay of the two maps generated. The results achieved from this study is SRTM DEM and Google Earth can able to produce thematic maps of situational tidal flood disaster so that it can be used as a parameter value calculation of the potential economic losses. This study also obtain the result that the area of ​​land affected by the tidal flood an area of ​​8339.31 hectares and the number of buildings reaching 78 299 pieces, which the district that has the highest impact on the tidal flood that North Semarang.

  20. The Black Top Hat function applied to a DEM: A tool to estimate recent incision in a mountainous watershed (Estibère Watershed, Central Pyrenees)

    Science.gov (United States)

    Rodriguez, Felipe; Maire, Eric; Courjault-Radé, Pierre; Darrozes, José

    2002-03-01

    The Top Hat Transform function is a grey-level image analysis tool that allows extracting peaks and valleys in a non-uniform background. This function can be applied onto a grey-level Digital Elevation Model (DEM). It is herein applied to quantify the volume of recent incised material in a mountainous Pyrenean watershed. Grey-level Closing operation applied to the Present-Day DEM gives a new image called ``paleo'' DEM. The Black Top Hat function consists in the subtraction of the ``paleo'' DEM with the Present-Day DEM. It gives a new DEM representing all valleys whose sizes range between the size of the structuring element and the null value as no threshold is used. The calculation of the incised volume is directly derived from the subtraction between the two DEM's. The geological significance of the quantitative results is discussed.

  1. Digital Elevation Model (DEM), Published in 1996, 1:2400 (1in=200ft) scale, Shawano County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Digital Elevation Model (DEM) dataset, published at 1:2400 (1in=200ft) scale, was produced all or in part from Orthoimagery information as of 1996. Data by this...

  2. Digital Elevation Model (DEM), Published in 2007, 1:12000 (1in=1000ft) scale, Door County, Wisconsin.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Digital Elevation Model (DEM) dataset, published at 1:12000 (1in=1000ft) scale, was produced all or in part from LIDAR information as of 2007. Data by this...

  3. VT Lidar Hydro-flattened DEM (0.7 meter) - 2013 - Rutland/West Washington/Grand Isle

    Data.gov (United States)

    Vermont Center for Geographic Information — (Link to Metadata) This metadata applies to the following collection area: Rutland/GI Counties 2013 0.7m and Digital Elevation Model (DEM) datasets of various...

  4. Digital Elevation Model (DEM), digital elevation model, Published in unknown, Louisiana State University - Louisiana Geographic Information Center.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Digital Elevation Model (DEM) dataset, was produced all or in part from LIDAR information as of unknown. It is described as 'digital elevation model'. Data by...

  5. Joint use of multi-orbit high-resolution SAR interferometry for DEM generation in mountainous area

    KAUST Repository

    Zhang, Lu

    2014-07-01

    SAR interferometry has long been regarded as an effective tool for wide-area topographic mapping in hilly and mountainous areas. However, quality of InSAR DEM product is usually affected by atmospheric disturbances and decorrelation-induced voids, especially for data acquired in repeat-pass mode. In this paper, we proposed an approach for improved topographic mapping by optimal fusion of multi-orbit InSAR DEMs with correction of atmospheric phase screen (APS). An experimental study with highresolution TerraSAR-X and COSMO-SkyMed datasets covering a mountainous area was carried out to demonstrate the effectiveness of the proposed approach. Validation with a reference DEM of scale 1:50,000 indicated that vertical accuracy of the fused DEM can be better than 5 m.

  6. Digital Elevation Model (DEM), Published in 2005, 1:24000 (1in=2000ft) scale, Sauk County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Digital Elevation Model (DEM) dataset, published at 1:24000 (1in=2000ft) scale, was produced all or in part from LIDAR information as of 2005. Data by this...

  7. Digital Elevation Model (DEM), Published in 2000, 1:7200 (1in=600ft) scale, Southern Georgia Regional Commission.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Digital Elevation Model (DEM) dataset, published at 1:7200 (1in=600ft) scale as of 2000. Data by this publisher are often provided in State Plane coordinate...

  8. Digital Elevation Model (DEM), Published in 2000, 1:12000 (1in=1000ft) scale, Off.of Admin - ITSD.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Digital Elevation Model (DEM) dataset, published at 1:12000 (1in=1000ft) scale, was produced all or in part from Other information as of 2000. Data by this...

  9. Digital Elevation Model (DEM), Published in 2004, 1:2400 (1in=200ft) scale, St. Croix County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Digital Elevation Model (DEM) dataset, published at 1:2400 (1in=200ft) scale, was produced all or in part from Orthoimagery information as of 2004. Data by this...

  10. Digital Elevation Model (DEM), Published in unknown, 1:4800 (1in=400ft) scale, Stokes County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Digital Elevation Model (DEM) dataset, published at 1:4800 (1in=400ft) scale, was produced all or in part from LIDAR information as of unknown. Data by this...

  11. A Multi-Scale Hybrid CFD-DEM-PBM Description of a Fluid-Bed Granulation Process

    National Research Council Canada - National Science Library

    Maitraye Sen; Dana Barrasso; Ravendra Singh; Rohit Ramachandran

    2014-01-01

    .... The fluid flow field has been solved implementing CFD principles and the behavior of the solid particles has been modeled using DEM techniques whereas the change in particle size has been quantified...

  12. Defining optimal DEM resolutions and point densities for modelling hydrologically sensitive areas in agricultural catchments dominated by microtopography

    Science.gov (United States)

    Thomas, I. A.; Jordan, P.; Shine, O.; Fenton, O.; Mellander, P.-E.; Dunlop, P.; Murphy, P. N. C.

    2017-02-01

    Defining critical source areas (CSAs) of diffuse pollution in agricultural catchments depends upon the accurate delineation of hydrologically sensitive areas (HSAs) at highest risk of generating surface runoff pathways. In topographically complex landscapes, this delineation is constrained by digital elevation model (DEM) resolution and the influence of microtopographic features. To address this, optimal DEM resolutions and point densities for spatially modelling HSAs were investigated, for onward use in delineating CSAs. The surface runoff framework was modelled using the Topographic Wetness Index (TWI) and maps were derived from 0.25 m LiDAR DEMs (40 bare-earth points m-2), resampled 1 m and 2 m LiDAR DEMs, and a radar generated 5 m DEM. Furthermore, the resampled 1 m and 2 m LiDAR DEMs were regenerated with reduced bare-earth point densities (5, 2, 1, 0.5, 0.25 and 0.125 points m-2) to analyse effects on elevation accuracy and important microtopographic features. Results were compared to surface runoff field observations in two 10 km2 agricultural catchments for evaluation. Analysis showed that the accuracy of modelled HSAs using different thresholds (5%, 10% and 15% of the catchment area with the highest TWI values) was much higher using LiDAR data compared to the 5 m DEM (70-100% and 10-84%, respectively). This was attributed to the DEM capturing microtopographic features such as hedgerow banks, roads, tramlines and open agricultural drains, which acted as topographic barriers or channels that diverted runoff away from the hillslope scale flow direction. Furthermore, the identification of 'breakthrough' and 'delivery' points along runoff pathways where runoff and mobilised pollutants could be potentially transported between fields or delivered to the drainage channel network was much higher using LiDAR data compared to the 5 m DEM (75-100% and 0-100%, respectively). Optimal DEM resolutions of 1-2 m were identified for modelling HSAs, which balanced the need

  13. Der Umlauf der spanischen Handschriften aus dem Antiquariat Leo Liepmannssohns in Paris und Berlin

    Directory of Open Access Journals (Sweden)

    Romero Naranjo, Francisco Javier

    2004-12-01

    Umlauf dieser Handschriften anstellte. Der Forschungsgegenstand beinhaltet eine Sammlung von mehr als 300 Heften, die in der Musikabteilung der Staatsbibliothek PreuBischer Kulturbesitz zu Berlin einzusehen sind. Die Hefte umfassen die Jahreskataloge des Liepmannssohnschen Antiquariates (Berlin der Jahre 1866 bis 1923. Jeder Katalog hat alie Verkäufe des jeweiligen Jahres in alphabetischer Reihenfolge aufgelistet und enthält neben Handschriften auch Literatur, Musikabhandlungen und Portraits verschiedener Komponisten. In diesen Katalogen sind sehr viele spanische Handschriften aufgeführt. Der Umlauf all dieser Handschriften ist so wichtig, dass Leo Liepmannssohn 1900 einen Katalog nur mit spanischen und portugiesischen Handschriften veroffendicht hat. In jenem Jahr hatte Liepmannssohn 291 spanische und portugiesische Handschriften versteigert. In diesen Versteigerungen tauchten bekannte - aber auch viele unbekannte - Dokumente, Handschriften und Musikabhandlungen auf. Durch diese Forschung wurden die Kenntnisse über Kompositionen verschiedener spanischer Komponisten des XVI. bis XIX. Jh. erweitert und im Ausland - speziell in Berlin - verbreitet.

  14. DEM EXTRACTION FROM WORLDVIEW-3 STEREO-IMAGES AND ACCURACY EVALUATION

    Directory of Open Access Journals (Sweden)

    F. Hu

    2016-06-01

    Full Text Available This paper validates the potentials of Worldview-3 satellite images in large scale topographic mapping, by choosing Worldview-3 along-track stereo-images of Yi Mountain area in Shandong province China for DEM extraction and accuracy evaluation. Firstly, eighteen accurate and evenly-distributed GPS points are collected in field and used as GCPs/check points, the image points of which are accurately measured, and also tie points are extracted from image matching; then, the RFM-based block adjustment to compensate the systematic error in image orientation is carried out and the geo-positioning accuracy is calculated and analysed; next, for the two stereo-pairs of the block, DSMs are separately constructed and mosaicked as an entirety, and also the corresponding DEM is subsequently generated; finally, compared with the selected check points from high-precision airborne LiDAR point cloud covering the same test area, the accuracy of the generated DEM with 2-meter grid spacing is evaluated by the maximum (max., minimum (min., mean and standard deviation (std. values of elevation biases. It is demonstrated that, for Worldview-3 stereo-images used in our research, the planimetric accuracy without GCPs is about 2.16 m (mean error and 0.55 (std. error, which is superior to the nominal value, while the vertical accuracy is about -1.61 m (mean error and 0.49 m (std. error; with a small amount of GCPs located in the center and four corners of the test area, the systematic error can be well compensated. The std. value of elevation biases between the generated DEM and the 7256 LiDAR check points are about 0.62 m. If considering the potential uncertainties in the image point measurement, stereo matching and also elevation editing, the accuracy of generating DEM from Worldview-3 stereo-images should be more desirable. Judging from the results, Worldview-3 has the potential for 1:5000 or even larger scale mapping application.

  15. Dem Extraction from WORLDVIEW-3 Stereo-Images and Accuracy Evaluation

    Science.gov (United States)

    Hu, F.; Gao, X. M.; Li, G. Y.; Li, M.

    2016-06-01

    This paper validates the potentials of Worldview-3 satellite images in large scale topographic mapping, by choosing Worldview-3 along-track stereo-images of Yi Mountain area in Shandong province China for DEM extraction and accuracy evaluation. Firstly, eighteen accurate and evenly-distributed GPS points are collected in field and used as GCPs/check points, the image points of which are accurately measured, and also tie points are extracted from image matching; then, the RFM-based block adjustment to compensate the systematic error in image orientation is carried out and the geo-positioning accuracy is calculated and analysed; next, for the two stereo-pairs of the block, DSMs are separately constructed and mosaicked as an entirety, and also the corresponding DEM is subsequently generated; finally, compared with the selected check points from high-precision airborne LiDAR point cloud covering the same test area, the accuracy of the generated DEM with 2-meter grid spacing is evaluated by the maximum (max.), minimum (min.), mean and standard deviation (std.) values of elevation biases. It is demonstrated that, for Worldview-3 stereo-images used in our research, the planimetric accuracy without GCPs is about 2.16 m (mean error) and 0.55 (std. error), which is superior to the nominal value, while the vertical accuracy is about -1.61 m (mean error) and 0.49 m (std. error); with a small amount of GCPs located in the center and four corners of the test area, the systematic error can be well compensated. The std. value of elevation biases between the generated DEM and the 7256 LiDAR check points are about 0.62 m. If considering the potential uncertainties in the image point measurement, stereo matching and also elevation editing, the accuracy of generating DEM from Worldview-3 stereo-images should be more desirable. Judging from the results, Worldview-3 has the potential for 1:5000 or even larger scale mapping application.

  16. Use of thermal infrared pictures for retrieving intertidal DEM by the waterline method: advantages and limitations

    Science.gov (United States)

    Gaudin, D.; Delacourt, C.; Allemand, P.

    2010-12-01

    Digital Elevation Models (DEM) of the intertidal zones have a growing interest for ecological and land development purposes. They are also a fundamental tool for monitoring current sedimentary movements in those low energy environments. Such DEMs have to be constructed with a centimetric resolution as the topographic changes are not predictable and as sediment displacements are weak. Direct construction of DEM by GPS in these muddy environment is difficult: photogrammetric techniques are not efficient on uniform coloured surfaces and terrestrial laser scans are difficult to stabilize on the mud, due to humidity. In this study, we propose to improve and to apply the waterline method to retrieve DEMs in intertidal zones. This technique is based on monitoring accurately the boundary between sand and water during a whole tide rise with thermal infrared images. The DEM is made by stacking all these lines calibrated by an immersed pressure sensor. Using thermal infrared pictures, instead of optical ones, improves the detection of the waterline, since mud and water have very different responses to sun heating and a large emissivity contrast. However, temperature retrieving from thermal infrared data is not trivial, since the luminance of an object is the sum of a radiative part and a reflexive part, whose relative proportions are given by the emissivity. In the following equation, B accounts for the equivalent blackbody luminance, and Linc is the incident luminance : Ltot}=L{rad}+L_{refl=ɛ B+(1-ɛ )Linc The infrared waterline technique has been used for the monitoring of a beach located on the Aber Benoit, 8.5km away from the open sea. The site is mainly constituted of mud, and waves are very small (less than one centimeter high), which are the ideal conditions for using the waterline method. A few measurements have been made to make differential heigh maps of sediments. We reached a mean resolution of 2cm and a vertical accuracy better than one centimeter. The results

  17. “Die Lexik mit dem semantischen Merkmal ‚Emotionalität’ der deutschen und der makedonischen Gegenwartssprache“

    OpenAIRE

    Ivanovska, Biljana

    2005-01-01

    Im Mittelpunkt dieses Beitrags steht die Zusammenfassung der Doktorarbeit: “Die Lexik mit dem semantischen Merkmal ‚Emotionalität’ der deutschen und der makedonischen Gegenwartssprache“ und die Untersuchung der emotional wertenden Lexik beider Sprachsysteme mit einem kontrastiven Sprachvergleich. “Die Lexik mit dem semantischen Merkmal ‚Emotionalität’ der deutschen und der makedonischen Gegewartssprache“ wird als Doktorarbeit an der Philologischen Fakultät „Blaze Koneski“ in Skopje verteidigt...

  18. Experiments on DEM interpolation based on regular grid%基于规则格网的DEM插值实验

    Institute of Scientific and Technical Information of China (English)

    张一帆; 王青山

    2016-01-01

    Through terrain modeling ,this experiment turns six geomorphic membership functions into six terrain units grid DEM ,with seven grid densities :101 × 101 ,112 × 112 ,126 × 126 ,144 × 144 ,168 × 168 , 201 × 201 ,and 257 × 257 .Using IDW and other six interpolation algorithms ,it interpolates the first six densities of grid DEM into 257 × 257 grid DEM ;Then it selects some checkpoints from the original 257 × 257 DEM randomly ,calculating residuals and RMSE for further statistical analysis .With interpolation experiments in group ,the methods of controlling variable and variance analysis are used to analyze the effects of terrain morphology ,sampling density and interpolation algorithms on grid DEM accuracy .%通过地形建模 ,将6个地形隶属函数按照101 × 101 ,112 × 112 ,126 × 126 ,144 × 144 ,168 × 168 ,201 × 201 , 257 × 257 7种格网密度生成6种局部地形单元的规则格网DEM ;使用反距离加权(IDW)等7种插值算法 ,将前6种格网密度下的DEM插值成257 × 257规格 ;从原始257 × 257DEM 中随机抽取检查点计算残差 ,并对残差中误差进行分析.通过分组插值实验 ,运用控制变量法、方差分析等方法研究地貌类型、采样密度和插值算法对DEM 插值精度的影响.

  19. Dimensionen politischer Konflikte : die Analyse von namentlichen Abstimmungen in Parlamenten mit dem Verfahren der Mokken-Skalierung

    OpenAIRE

    1991-01-01

    In dem Aufsatz stellen die Autoren ein probalistisches Skalierungsmodell ("Mokken-Skalierung") vor, mit dem sie das Abstimmungsverhalten der Abgeordneten und daran anknüpfend die Konfliktstrukturen der Frankfurter Nationalversammlung und der französischen Assemble Nationale Constituante analysieren. Im Zentrum der methodologischen Überlegungen steht dabei die oft schwierige "Übersetzung" von theoretischen Begriffen (wie Industrialisierung, legitime Herrschaft, Klassenbewußtsein) in empirische...

  20. Digital Elevation Model (DEM), Our DEM was created by using the LiDAR data from our recent acquisition. The layer was created with the help of contour data, mass points & breaklines., Published in 2012, Not Applicable scale, Chippewa County Government.

    Data.gov (United States)

    NSGIC Local Govt | GIS Inventory — Digital Elevation Model (DEM) dataset current as of 2012. Our DEM was created by using the LiDAR data from our recent acquisition. The layer was created with the...

  1. Creating High Quality DEMs of Large Scale Fluvial Environments Using Structure-from-Motion

    Science.gov (United States)

    Javernick, L. A.; Brasington, J.; Caruso, B. S.; Hicks, M.; Davies, T. R.

    2012-12-01

    During the past decade, advances in survey and sensor technology have generated new opportunities to investigate the structure and dynamics of fluvial systems. Key geomatic technologies include the Global Positioning System (GPS), digital photogrammetry, LiDAR, and terrestrial laser scanning (TLS). The application of such has resulted in a profound increase in the dimensionality of topographic surveys - from cross-sections to distributed 3d point clouds and digital elevation models (DEMs). Each of these technologies have been used successfully to derive high quality DEMs of fluvial environments; however, they often require specialized and expensive equipment, such as a TLS or large format camera, bespoke platforms such as survey aircraft, and consequently make data acquisition prohibitively expensive or highly labour intensive, thus restricting the extent and frequency of surveys. Recently, advances in computer vision and image analysis have led to development of a novel photogrammetric approach that is fully automated and suitable for use with simple compact (non-metric) cameras. In this paper, we evaluate a new photogrammetric method, Structure-from-Motion (SfM), and demonstrate how this can be used to generate DEMs of comparable quality to airborne LiDAR, using consumer grade cameras at low costs. Using the SfM software PhotoScan (version 0.8.5), high quality DEMs were produced for a 1.6 km reach and a 3.3 km reach of the braided Ahuriri River, New Zealand. Photographs used for DEM creation were acquired from a helicopter flying at 600 m and 800 m above ground level using a consumer grade 10.1mega-pixel, non-metric digital camera, resulting in object space resolution imagery of 0.12 m and 0.16 m respectively. Point clouds for the two study reaches were generated using 147 and 224 photographs respectively, and were extracted automatically in an arbitrary coordinate system; RTK-GPS located ground control points (GCPs) were used to define a 3d non

  2. Coastal Digital Elevation Models (DEMs) for tsunami hazard assessment on the French coasts

    Science.gov (United States)

    Maspataud, Aurélie; Biscara, Laurie; Hébert, Hélène; Schmitt, Thierry; Créach, Ronan

    2015-04-01

    Building precise and up-to-date coastal DEMs is a prerequisite for accurate modeling and forecasting of hydrodynamic processes at local scale. Marine flooding, originating from tsunamis, storm surges or waves, is one of them. Some high resolution DEMs are being generated for multiple coast configurations (gulf, embayment, strait, estuary, harbor approaches, low-lying areas…) along French Atlantic and Channel coasts. This work is undertaken within the framework of the TANDEM project (Tsunamis in the Atlantic and the English ChaNnel: Definition of the Effects through numerical Modeling) (2014-2017). DEMs boundaries were defined considering the vicinity of French civil nuclear facilities, site effects considerations and potential tsunamigenic sources. Those were identified from available historical observations. Seamless integrated topographic and bathymetric coastal DEMs will be used by institutions taking part in the study to simulate expected wave height at regional and local scale on the French coasts, for a set of defined scenarii. The main tasks were (1) the development of a new capacity of production of DEM, (2) aiming at the release of high resolution and precision digital field models referred to vertical reference frameworks, that require (3) horizontal and vertical datum conversions (all source elevation data need to be transformed to a common datum), on the basis of (4) the building of (national and/or local) conversion grids of datum relationships based on known measurements. Challenges in coastal DEMs development deal with good practices throughout model development that can help minimizing uncertainties. This is particularly true as scattered elevation data with variable density, from multiple sources (national hydrographic services, state and local government agencies, research organizations and private engineering companies) and from many different types (paper fieldsheets to be digitized, single beam echo sounder, multibeam sonar, airborne laser

  3. Coupling photogrammetric data with DFN-DEM model for rock slope hazard assessment

    Science.gov (United States)

    Donze, Frederic; Scholtes, Luc; Bonilla-Sierra, Viviana; Elmouttie, Marc

    2013-04-01

    Structural and mechanical analyses of rock mass are key components for rock slope stability assessment. The complementary use of photogrammetric techniques [Poropat, 2001] and coupled DFN-DEM models [Harthong et al., 2012] provides a methodology that can be applied to complex 3D configurations. DFN-DEM formulation [Scholtès & Donzé, 2012a,b] has been chosen for modeling since it can explicitly take into account the fracture sets. Analyses conducted in 3D can produce very complex and unintuitive failure mechanisms. Therefore, a modeling strategy must be established in order to identify the key features which control the stability. For this purpose, a realistic case is presented to show the overall methodology from the photogrammetry acquisition to the mechanical modeling. By combining Sirovision and YADE Open DEM [Kozicki & Donzé, 2008, 2009], it can be shown that even for large camera to rock slope ranges (tested about one kilometer), the accuracy of the data are sufficient to assess the role of the structures on the stability of a jointed rock slope. In this case, on site stereo pairs of 2D images were taken to create 3D surface models. Then, digital identification of structural features on the unstable block zone was processed with Sirojoint software [Sirovision, 2010]. After acquiring the numerical topography, the 3D digitalized and meshed surface was imported into the YADE Open DEM platform to define the studied rock mass as a closed (manifold) volume to define the bounding volume for numerical modeling. The discontinuities were then imported as meshed planar elliptic surfaces into the model. The model was then submitted to gravity loading. During this step, high values of cohesion were assigned to the discontinuities in order to avoid failure or block displacements triggered by inertial effects. To assess the respective role of the pre-existing discontinuities in the block stability, different configurations have been tested as well as different degree of

  4. Simultaneous utilization of different nuclear medical examinations in a patient with Klippel-Trenaunay syndrome - vs. proteus syndrome; Simultaner Einsatz verschiedener nuklearmedizinischer Verfahren bei Klippel-Trenaunay-Syndrom - vs. Proteus-Syndrom

    Energy Technology Data Exchange (ETDEWEB)

    Rink, T.; Baum, R.P.; Hoer, G. [Klinik fuer Nuklearmedizin des Zentrums der Radiologie, Johann Wolfgang Goethe-Universitaet, Frankfurt am Main (Germany); Menzel, I.; Niemczyk, M.; Kaufmann, R. [Zentrum fuer Dermatologie und Venerologie, Johann Wolfgang Goethe-Universitaet, Frankfurt am Main (Germany); Fuchs, S. [Inst. fuer Humangenetik, Johann Wolfgang Goethe-Universitaet, Frankfurt am Main (Germany); Heller, K. [Zentrum fuer Chirurgie, Johann Wolfgang Goethe-Universitaet, Frankfurt am Main (Germany)

    1997-08-01

    zwischenzeitlich durchgefuehrter diagnostischer Massnahmen konnte die Verdachtsdiagnose bis zu diesem Zeitpunkt nicht bestaetigt werden. Anlaesslich einer ausgepraegten lokalen Infektion im Hueftbereich, die die Frage nach einer operativen Sanierung aufwarf, wurden - um eine laengere Ruhigstellung des Jungen zu vermeiden - am gleichen Tag eine Lymphabflussszintigraphie, eine Radionuklidphlebographie und -ventrikulographie sowie eine Blutpool- und Skelettszintigraphie durchgefuehrt. Die Ergebnisse liessen ein Lymphangiom vermuten, das nach operativer Entfernung des Befundes histologisch bestaetigt werden konnte. Unter Beruecksichtigung aller Untersuchungsergebnisse duerfen es sich bei dem zugrundeliegenden Krankheitsbild nicht um ein Klippel-Trenaunay-Syndrom, sondern um das seltene Proteus-Syndrom handeln. (orig.)

  5. Influence of aerodynamics on the heat absorption of convection cooled turbine blades. Final report; Einfluss der Aerodynamik auf die Waermeaufnahme konvektionsgekuehlter Turbinenschaufeln. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Wittig, S.; Schiele, R.; Sieger, K.; Schulz, A.

    1995-12-31

    The objective of this project is the integration of aerodynamic and thermal design in the example of convection cooled turbine blades. For this purpose, in a first section of this project, a boundary-layer numerical method is to be further developed to permit the calculation of heat transfer and fluidic losses of convection cooled cascades. Using this improved calculation method, a prototype aerothermic design of a turbine stator is to be conducted in a second section of the project. Finally, the aerodynamic losses and the heat transfer behavior of the new cascade are to be experimentally investigated to make a design assessment. Due to its decisive importance to aerodynamics and heat transfer in gas-turbine blades, special interest is focused on the process of laminar-turbulent transition. (orig.) [Deutsch] Ziel des Vorhabens ist daher die Zusammenfuehrung der aerodynamischen und thermischen Auslegung am Beispiel konvektionsgekuehlter Turbinenschaufeln. Dazu soll in einem ersten Teil des Vorhabens ein Grenzschichtrechenverfahren weiterentwickelt werden, das die Berechnung des Waermeuebergangs und der stroemungsmechanischen Verluste konvektionsgekuehlter Schaufelgitter ermoeglicht. Mit Hilfe dieses verbesserten Berechnungsverfahrens soll in einem zweiten Teil des Vorhabens eine prototypische aerothermische Auslegung eines Turbinenleitrades durchgefuehrt werden. Schliesslich sollen die aerodynamischen Verluste und das Waermeuebergangsverhalten des neuen Schaufelgitters experimentell untersucht und somit die Auslegung bewertet werden. Aufgrund seiner entscheidenden Bedeutung fuer Aerodynamik und Waermeuebergang an Gasturbinenschaufeln gilt dem Vorgang des laminar-turbulenten Umschlags dabei besonderes Interesse. (orig.)

  6. Digital Elevation Model (DEM), 1.7 meter DEM in Urban Areas, 5 Meter DEM in National Forest, flown as part of the LAR-IAC project, Published in 2006, 1:600 (1in=50ft) scale, County of Los Angeles.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Digital Elevation Model (DEM) dataset, published at 1:600 (1in=50ft) scale, was produced all or in part from LIDAR information as of 2006. It is described as...

  7. The art of unhappiness: Elfriede Jelineks The Pianist between tradition and mass media

    Directory of Open Access Journals (Sweden)

    Luis S. Krausz

    2011-01-01

    Full Text Available Der Ziel dieses Artikels ist die Kontextualisierung von Elfriede Jelineks Roman Die Klavierspielerin innerhalb einer kritischen Tradition der österreichischen Literatur des 20. Jahrhunderts, zu welcher fast alle bedeutenden Autoren dieses Landes in den 20er. und 30er. Jahren irgendwie gehören. Nach 1945 gelang es dem österreichischen literarischen Establishment eine harmonistishce Ideologie durchzusetzen, die alle gesellschaftliche Gegensätze durch eine eskapistische Tendenz und eine Rückkehr zu Elemente der habsburgische Ideologie ersetzten. Die Protest-Literatur der 1980er. kann als Reaktion gegen diese sogenannte Österreich Ideologie verstanden werden. Die Klavierspielerin scheint auf einem Konflikt strukturiert zu sein und dieser Konflikt zeichnet sich als Opposition zwischen einer festen Beziehung zur österreichischen Vergangenheit, ins besondere zur vergangenen Musiktradition einerseits, und dem ständigen Einfluss der globalisierten Mass-media andererseits. Erika Kohut, ihre Mutter und Walter Klemmer, die Protagonisten des Romans, können daher als Sinnbilder verschiedener Weltanschauungen gedeutet werden, die zwischen den Trümmern der Ideologie der verschollenen Doppelmonarchie und der Integration in der globalisierten Welt schwanken. Dadurch können sie auch als bedeutende Symbole der österreichischen Gesellschaft unserer Zeit verstanden werden

  8. Analysis of Topographic Feature with SRTM DEM and ASTER GDEM Data and Railway Alignment%基于SRTM DEM,ASTER GDEM 地貌特征分析与铁路选线

    Institute of Scientific and Technical Information of China (English)

    高山

    2012-01-01

    研究目的:SRTM DEM,ASTER GDEM 数据具有全球范围、免费获取、精度较高的优点,结合复杂山区铁路工程,评价其数据精度,研究线路地貌特征,辅助铁路选线.研究结论:SRTM DEM,ASTER GDEM 数据由于各自存在较大的系统误差,通过采用高程精度评价、DEM融合、高程基准偏移、DEM重采样方法提高数字高程精度,进而构建大范围、高精度、可视化的三维数字地貌模型,有助于分析构造地貌特征、岩溶水文地质条件、地质灾害发育规律,提高铁路选线质量和效率.%Research purposes: The SRTM DEM and ASTER GDEM data have the advantages of the global scope, free access and high precision. The data were appliied in building railways in mountain area with complex geological condition to evaluate the data accuracy and study the topographic feature for assisting the railway alignment. Research conclusions:As the SRTM DEM and ASTER GDEM data have its own system error, the measures, such as the digital elevation accuracy evaluation, DEM fusion, elevation datum offset and DEM re - sampling, should be taken for improving the DEM accuracy and building a large range, high accuracy and visual digital topographic feature model to assist the analysis of the structural topographic feature, the geological condition of karst hydrology and the development regulation of geological disaster in order to enhance the quality and efficiency of railway alignment.

  9. A new 100-m Digital Elevation Model of the Antarctic Peninsula derived from ASTER Global DEM: methods and accuracy assessment

    Directory of Open Access Journals (Sweden)

    A. J. Cook

    2012-10-01

    Full Text Available A high resolution surface topography Digital Elevation Model (DEM is required to underpin studies of the complex glacier system on the Antarctic Peninsula. A complete DEM with better than 200 m pixel size and high positional and vertical accuracy would enable mapping of all significant glacial basins and provide a dataset for glacier morphology analyses. No currently available DEM meets these specifications. We present a new 100-m DEM of the Antarctic Peninsula (63–70° S, based on ASTER Global Digital Elevation Model (GDEM data. The raw GDEM products are of high-quality on the rugged terrain and coastal-regions of the Antarctic Peninsula and have good geospatial accuracy, but they also contain large errors on ice-covered terrain and we seek to minimise these artefacts. Conventional data correction techniques do not work so we have developed a method that significantly improves the dataset, smoothing the erroneous regions and hence creating a DEM with a pixel size of 100 m that will be suitable for many glaciological applications. We evaluate the new DEM using ICESat-derived elevations, and perform horizontal and vertical accuracy assessments based on GPS positions, SPOT-5 DEMs and the Landsat Image Mosaic of Antarctica (LIMA imagery. The new DEM has a mean elevation difference of −4 m (± 25 m RMSE from ICESat (compared to −13 m mean and ±97 m RMSE for the original ASTER GDEM, and a horizontal error of less than 2 pixels, although elevation accuracies are lower on mountain peaks and steep-sided slopes. The correction method significantly reduces errors on low relief slopes and therefore the DEM can be regarded as suitable for topographical studies such as measuring the geometry and ice flow properties of glaciers on the Antarctic Peninsula. The DEM is available for download from the NSIDC website: http://nsidc.org/data/nsidc-0516.html (A real-time flood forecasting and simulation system based on GIS and DEM: Analysis of sensitivity to scale factors

    Science.gov (United States)

    Garcia, Sandra G.

    The hydrometeorological telemetric networks in real time interrelated with weather forecasting and rainfall information obtained from remote sensing, constitute real forecasting and protection instruments in the event of flash flooding, so typical of semiarid environments. In this Thesis, spatial analysis approached with functions embedded in a Geographical Information System (GIS) are proposed. The aims are: (a) To combine efficiently information from different sources (telemetric networks and radar-satellite technology). (b) To develop methodology of application of spatially distributed and hybrid hydrologic models, which are topographically based and event-oriented. (c) To extract automatically from Digital Elevation Models (DEM) the relevant parameters of the hydrologic models used. When extracting the drainage networks from a DEM, various questions arise: what is the most suitable drainage density for the hydrographic network? What degree of affection does the selection of DEM cell size have on the hydrologic results, or are they not sensitive to it? Can any invariable property by defined with the scale which characterizes indexes or parameters based on the drainage network hierarchy? A clear inter-relationship can be seen between the geomorphological and hydrologic parameters and the DEM resolution. The morphometric parameters are also affected by threshold area variation. It is proposed a methodology to identify a priori the range of DEM resolutions and threshold areas for in which the parameters present a certain stability for modelling based on drainage networks topology. When working with spatially distributed models, several questions crop up: Are the distributed parameters derived from DEM and the complete hydrologic results affected by cell size? Is it feasible to identify invariable properties with the scale which characterizes the spatial distributions of the parameters? The terrain slope and the flow path length are affected by the DEM cell

  10. Elevation validation and geomorphic metric comparison with focus on ASTER GDEM2, SRTM- C, ALOS World 3D, and TanDEM-X

    Science.gov (United States)

    Purinton, Benjamin; Bookhagen, Bodo

    2017-04-01

    Geomorphologists use digital elevation models (DEMs) to quantify changes in topography - often without rigorous accuracy assessments. In this study we validate and compare elevation accuracy and derived geomorphic metrics from the current generation of satellite-derived DEMs on the southern Central Andean Plateau. The average elevation of 3.7 km, diverse topography and relief, lack of vegetation, and clear skies create ideal conditions for remote sensing in this study area. DEMs at resolutions of 5-30 m are sourced from open-access, research agreement, and commercial outlets, with a focus on the 30 m SRTM-C, 30 m ASTER GDEM2, 12 m TanDEM-X, and 5 m ALOS World 3D data. In addition to these edited products, manually generated DEMs included 10 m single-CoSSC TerraSAR-X / TanDEM-X DEMs and a 30 m stacked ASTER L1A stereopair DEM. We assessed vertical accuracy by comparing standard deviations (SD) of the DEM elevation versus 307,509 differential GPS (dGPS) measurements with employed a Fourier analysis to identify DEM frequencies and their spectral power. The optical 5 m ALOS World 3D DEM shows high-frequency noise in 2-8 pixel steps, with no corresponding landscape features in this highly diffusive, vegetation-free environment. Finally, we explore the geomorphometric potential of the higher-quality 12 m TanDEM-X DEM through a hillslope length and surface roughness assessment across steep environmental, climatic and topographic gradients in the Quebrada del Toro catchment, west of Salta, Argentina.

  11. Computer vision: automating DEM generation of active lava flows and domes from photos

    Science.gov (United States)

    James, M. R.; Varley, N. R.; Tuffen, H.

    2012-12-01

    Accurate digital elevation models (DEMs) form fundamental data for assessing many volcanic processes. We present a photo-based approach developed within the computer vision community to produce DEMs from a consumer-grade digital camera and freely available software. Two case studies, based on the Volcán de Colima lava dome and the Puyehue Cordón-Caulle obsidian flow, highlight the advantages of the technique in terms of the minimal expertise required, the speed of data acquisition and the automated processing involved. The reconstruction procedure combines structure-from-motion and multi-view stereo algorithms (SfM-MVS) and can generate dense 3D point clouds (millions of points) from multiple photographs of a scene taken from different positions. Processing is carried out by automated software (e.g. http://blog.neonascent.net/archives/bundler-photogrammetry-package/). SfM-MVS reconstructions are initally un-scaled and un-oriented so additional geo-referencing software has been developed. Although this step requires the presence of some control points, the SfM-MVS approach has significantly easier image acquisition and control requirements than traditional photogrammetry, facilitating its use in a broad range of difficult environments. At Colima, the lava dome surface was reconstructed from recent and archive images taken from light aircraft over flights (2007-2011). Scaling and geo-referencing was carried out using features identified in web-sourced ortho-imagery obtained as a basemap layer in ArcMap - no ground-based measurements were required. Average surface measurement densities are typically 10-40 points per m2. Over mean viewing distances of ~500-2500 m (for different surveys), RMS error on the control features is ~1.5 m. The derived DEMs (with 1-m grid resolution) are sufficient to quantify volumetric change, as well as to highlight the structural evolution of the upper surface of the dome following an explosion in June 2011. At Puyehue Cord

  12. Influence of the adsorption layers of surfactants on the extraction behaviour of heavy metals. Liquid-liquid extraction; Einfluss von Tensidadsorptionsschichten auf das Extraktionsverhalten von Schwermetallen. T. 1. Fluessig/fluessig-Extraktion

    Energy Technology Data Exchange (ETDEWEB)

    Raatz, S.; Haertel, G. [Technische Univ. Bergakademie Freiberg (Germany). Lehrstuhl fuer Umweltverfahrenstechnik

    1998-05-01

    Depending on the type of the head group (anionic, cationic and nonionic) as well as the structure the adsorption layers of surfactants on the liquid/liquid interface have an essential influence on the extraction behavior and the mass transfer of heavy metals (Cd, Zn, Pb, Cr). By choosing the right type and concentration of surfactant it should therefore be possible to accelerate the mass transfer thus improving the extraction rate (e.g. sodium dodecylsulfonate), or even to prevent a mass transfer almost completely (e.g. i-octylphenyl ethoxylate). The purpose of this paper is to control the selectivity of the mass-transfer accompanied by reaction beyond fluid interfaces with the help of surfactants as well as to clarify the effective mechanisms. (orig.) [Deutsch] Tensidadsorptionsschichten haben in Abhaengigkeit von der Art ihrer Kopfgruppierung (anionisch, kationisch und nichtionisch), Struktur und Konzentration einen wesentlichen Einfluss auf das Extraktionsverhalten bzw. den Stoffuebergang von Schwermetallen (Cd, Zn, Pb, Cr) ueber die Fluessig/fluessig-Phasengrenze. Mit der richtigen Wahl eines Tensids (Art, Konzentration) ist es daher moeglich, den Stofftransport zu beschleunigen und den Extraktionsgrad bedeutend zu verbessern (z.B. Na-Dodecylsulfonat) oder auch den Stofftransport nahezu zu unterbinden (z.B. i-Octylphenylethoxylat) oder auch den Stofftransport nahezu zu unterbinden (z.B. i-Octylphenylethoxylat). Das Ziel dieser Arbeit ist es, die Selektivitaet der reaktiven Stoffuebertragung ueber fluide Phasengrenzen durch entsprechend gewaehlte Adsorptionsschichten gezielt zu steuern und die dabei wirkenden Mechanismen aufzuklaeren. (orig.)

  13. Effects of air traffic on cirrus cloud formation in Europe. Final report of the development area environmental and climate research; Untersuchungen zum Einfluss des Flugverkehrs auf die Cirrus-Bewoelkung in Europa. Endbericht im Foerdergebiet Umwelt und Klimaforschung

    Energy Technology Data Exchange (ETDEWEB)

    Mannstein, H.; Wendling, P.

    2001-06-01

    The cloud cover over Europe caused by linear condensation trails has been investigated already in earlier studies. However, after quite a short period of time, these can no longer be distinguished from natural cirrus clouds. There were no data on the effect of air travel on cirrus formation. This study investigated the effects of air travel on cirrus cloud formation by investigating a time series of METEOSAT data and relating it to air travel data in high temporal and local resolution. (orig.) [German] Der Bedeckungsgrad an deutlich im Satellitenbild erkennbaren, linearen Kondensstreifen ueber Europa wurde bereits untersucht. Nach relativ kurzer Zeit sind Kondensstreifen jedoch mit den bisher bekannten Fernerkundungsmethoden nicht mehr von natuerlichen Cirren zu unterscheiden. In welchem Masse der Flugverkehr zur Cirrus-Bewoelkung beitraegt, war bisher nicht bekannt. In dieser Arbeit wurde mit hoher Signifikanz der Einfluss des Flugverkehrs auf die Cirrusbedeckung, wie sie sich ans METEOSAT-Daten ableiten laesst, nachgewiesen. Dazu wurde eine Zeitserie von METEOSAT-Daten im Vergleich zu zeitlich und raeumlich hochaufgeloesten Flugverkehrsdaten untersucht. (orig.)

  14. ArcticDEM; A Publically Available, High Resolution Elevation Model of the Arctic

    Science.gov (United States)

    Morin, Paul; Porter, Claire; Cloutier, Michael; Howat, Ian; Noh, Myoung-Jong; Willis, Michael; Bates, Brian; Willamson, Cathleen; Peterman, Kennith

    2016-04-01

    A Digital Elevation Model (DEM) of the Arctic is needed for a large number of reasons, including: measuring and understanding rapid, ongoing changes to the Arctic landscape resulting from climate change and human use and mitigation and adaptation planning for Arctic communities. The topography of the Arctic is more poorly mapped than most other regions of Earth due to logistical costs and the limits of satellite missions with low-latitude inclinations. A convergence of civilian, high-quality sub-meter stereo imagery; petascale computing and open source photogrammetry software has made it possible to produce a complete, very high resolution (2 to 8-meter posting), elevation model of the Arctic. A partnership between the US National Geospatial-intelligence Agency and a team led by the US National Science Foundation funded Polar Geospatial Center is using stereo imagery from DigitalGlobe's Worldview-1, 2 and 3 satellites and the Ohio State University's Surface Extraction with TIN-based Search-space Minimization (SETSM) software running on the University of Illinois's Blue Water supercomputer to address this challenge. The final product will be a seemless, 2-m posting digital surface model mosaic of the entire Arctic above 60 North including all of Alaska, Greenland and Kamchatka. We will also make available the more than 300,000 individual time-stamped DSM strip pairs that were used to assemble the mosaic. The Arctic DEM will have a vertical precision of better than 0.5m and can be used to examine changes in land surfaces such as those caused by permafrost degradation or the evolution of arctic rivers and floodplains. The data set can also be used to highlight changing geomorphology due to Earth surface mass transport processes occurring in active volcanic and glacial environments. When complete the ArcticDEM will catapult the Arctic from the worst to among the best mapped regions on Earth.

  15. Development and Evaluation of Simple Measurement System Using the Oblique Photo and dem

    Science.gov (United States)

    Nonaka, H.; Sasaki, H.; Fujimaki, S.; Naruke, S.; Kishimoto, H.

    2016-06-01

    When a disaster occurs, we must grasp and evaluate its damage as soon as possible. Then we try to estimate them from some kind of photographs, such as surveillance camera imagery, satellite imagery, photographs taken from a helicopter and so on. Especially in initial stage, estimation of decent damage situation for a short time is more important than investigation of damage situation for a long time. One of the source of damage situation is the image taken by surveillance camera, satellite sensor and helicopter. If we can measure any targets in these imagery, we can estimate a length of a lava flow, a reach of a cinder and a sediment volume in volcanic eruption or landslide. Therefore in order to measure various information for a short time, we developed a simplified measurement system which uses these photographs. This system requires DEM in addition to photographs, but it is possible to use previously acquired DEM. To measure an object, we require only two steps. One is the determination of the position and the posture in which the photograph is shot. We determine these parameters using DEM. The other step is the measurement of an object in photograph. In this paper, we describe this system and show the experimental results to evaluate this system. In this experiment we measured the top of Mt. Usu by using two measurement method of this system. Then we can measure it about one hour and the difference between the measurement results and the airborne LiDAR data are less than 10 meter.

  16. DEVELOPMENT AND EVALUATION OF SIMPLE MEASUREMENT SYSTEM USING THE OBLIQUE PHOTO AND DEM

    Directory of Open Access Journals (Sweden)

    H. Nonaka

    2016-06-01

    Full Text Available When a disaster occurs, we must grasp and evaluate its damage as soon as possible. Then we try to estimate them from some kind of photographs, such as surveillance camera imagery, satellite imagery, photographs taken from a helicopter and so on. Especially in initial stage, estimation of decent damage situation for a short time is more important than investigation of damage situation for a long time. One of the source of damage situation is the image taken by surveillance camera, satellite sensor and helicopter. If we can measure any targets in these imagery, we can estimate a length of a lava flow, a reach of a cinder and a sediment volume in volcanic eruption or landslide. Therefore in order to measure various information for a short time, we developed a simplified measurement system which uses these photographs. This system requires DEM in addition to photographs, but it is possible to use previously acquired DEM. To measure an object, we require only two steps. One is the determination of the position and the posture in which the photograph is shot. We determine these parameters using DEM. The other step is the measurement of an object in photograph. In this paper, we describe this system and show the experimental results to evaluate this system. In this experiment we measured the top of Mt. Usu by using two measurement method of this system. Then we can measure it about one hour and the difference between the measurement results and the airborne LiDAR data are less than 10 meter.

  17. Numerical probabilistic analysis for slope stability in fractured rock masses using DFN-DEM approach

    Directory of Open Access Journals (Sweden)

    Alireza Baghbanan

    2017-06-01

    Full Text Available Due to existence of uncertainties in input geometrical properties of fractures, there is not any unique solution for assessing the stability of slopes in jointed rock masses. Therefore, the necessity of applying probabilistic analysis in these cases is inevitable. In this study a probabilistic analysis procedure together with relevant algorithms are developed using Discrete Fracture Network-Distinct Element Method (DFN-DEM approach. In the right abutment of Karun 4 dam and downstream of the dam body, five joint sets and one major joint have been identified. According to the geometrical properties of fractures in Karun river valley, instability situations are probable in this abutment. In order to evaluate the stability of the rock slope, different combinations of joint set geometrical parameters are selected, and a series of numerical DEM simulations are performed on generated and validated DFN models in DFN-DEM approach to measure minimum required support patterns in dry and saturated conditions. Results indicate that the distribution of required bolt length is well fitted with a lognormal distribution in both circumstances. In dry conditions, the calculated mean value is 1125.3 m, and more than 80 percent of models need only 1614.99 m of bolts which is a bolt pattern with 2 m spacing and 12 m length. However, as for the slopes with saturated condition, the calculated mean value is 1821.8 m, and more than 80 percent of models need only 2653.49 m of bolts which is equivalent to a bolt pattern with 15 m length and 1.5 m spacing. Comparison between obtained results with numerical and empirical method show that investigation of a slope stability with different DFN realizations which conducted in different block patterns is more efficient than the empirical methods.

  18. Mobilization, complexation and translocation of aluminium and heavy metal ions in forest soils under the influence of atmogenic acidification. Preliminary final report for the period August 1, 1987 to July 31, 1989; Mobilisierung, Komplexierung und Translokation von Aluminium und Schwermetallionen in Waldboeden unter dem Einfluss atmogener Versauerung. Vorlaeufiger Schlussbericht fuer den Zeitraum 01.08.87 bis 31.07.89

    Energy Technology Data Exchange (ETDEWEB)

    Kreutzer, K.; Schierl, R.

    1991-12-31

    The Hoeglwald forest experiment was started in 1984 in order to study the effects of acid rain and lime on a healthy forest of older pines with good growth rates. The main field of interest was the problem of the aluminium and heavy metal dynamics in the soil. The ion species relevant for toxicity problems were characterized, as were organic substances that may act as complexing agents. The paper contains profile analyses of the investigation site and information on the analytical methods applied. The results are presented in graphical form. (LU). [Deutsch] Das Hoeglwaldexperiment wurde 1984 begonnen, um die Auswirkungen saurer Beregnung und Kalkung auf einen gesunden und gut wuechsigen Fichtenaltbestand zu untersuchen. Schwerpunkt war die Frage nach der Aluminium- und Schwermetalldynamik im Boden. Die einzelnen Ionenspezies, die fuer toxische Fragen von Bedeutung sein koennen, wurden charakterisiert, ebenso organische Substanzen, die z.B. als Komplexbildner in Betracht kommen. Die vorliegende Arbeit enthaelt Profilanalysen des Untersuchungsstandortes und Angaben zu durchgefuehrten analytischen Bestimmungsverfahren. Die Ergebnisse werden im wesentlichen anhand von Graphiken dargestellt. (LU).

  19. Investigations on the mechanisms change and growth of mammary gland tumor cells under the influence of antiestrogenic drugs and low-frequency magnetic fields; Untersuchung des Wirkungsmechanismus fuer die Veraenderung des Wachstums von Brustkrebszellen unter dem Einfluss von Onkostatika und niederfrequenten Magnetfeldern

    Energy Technology Data Exchange (ETDEWEB)

    Girgert, R.; Gruendker, C.; Hanf, V.

    2012-10-15

    In the present project we investigated the molecular mechanism of the decreased antiproliferative effect of the antiestrogenic drug Tamoxifen and the pineal gland hormone Melatonin on breast cancer cells in the presence of low-frequency electromagnetic fields. New unique incubators were developed for the exposure of the cells to controlled, highly homogenous magnetic fields. MCF-7 p40 cells exposed to 1.2 {mu}T expressed 20 genes more than two times stronger than control cells, MCF-7p181 cells 61 genes. 16 genes were expressed weaker in MCF-7p40 cells, 41 genes in MCF-7p181. The increased expression of the particularly interesting coactivators, AIB1 and SRC-1, and of urokinase plasminogen activator and plasminogen-activator inhibitor was confirmed using RT-PCR and Western blot. The corepressors, N-Cor and SMRT, and various metastasis-suppressor genes were expressed lower in the exposed cells. Investigations of signal transduction revealed only MAP-kinase Erk1 being more strongly activated after one hour exposure to the magnetic field, while stress-activated MAP-kinases, junK and p38, were not activated by the magnetic field or even slightly deactivated. Experiments on Melatonin action in the magnetic field showed that expression of the two Melatonin receptors, MT1 and RZR{alpha}, was only marginally altered at 1,2 {mu}T. Of the target genes of Melatonin expression of tumorsuppressors p53 and p21waf was decreased in the magnetic field whereas the decrease in expression of BRCA1 and c-myc by Melatonin was less strong in the magnetic field.

  1. INSAR Flat-earth Phase Removal Approach Based on DEM to Settlement Area

    OpenAIRE

    2016-01-01

    The difficulties of phase unwrapping was increased with the existence of flat-earth phase removal, at the same time, it covered up the real topographical conditions. In order to solve this problem, the paper presented a method of re-flattening. based on DEM to eliminate flat-earth phase, with the interferogram, and then chose some special control points to construct polynomial fitting, removed residual phase and noise. By analyzing the ALOS/PALSAR at the mine subsidence area, the contrast exp...

  2. Der Kalte Krieg in der Peripherie Griechische Physiker und Atomenergie nach dem Zweiten Weltkrieg

    Science.gov (United States)

    Vlahakis, George N.

    Die vorliegende Arbeit analysiert Ansichten griechischer Physiker zur Atomenergie und deren mögliche Anwendung nach dem Zweiten Weltkrieg, insbesondere während des Kalten Kriegs. Einerseits werden Ansichten von Physik- Professoren griechischer Universitäten präsentiert - beispielsweise von Dimitrios Hondros, der Student von Arnold Sommerfeld und Mitarbeiter von Peter Debye in München war, und andererseits wird die Politik der griechischen Regierung für die Etablierung eines Forschungsinstitutes diskutiert, das der Entwicklung der Atomenergie dienen sollte; ebenfalls wird eine öffentliche Meinungsumfrage zu diesen Thema, die in den Tageszeitungen der damaligen Zeit präsentiert wurde, diskutiert.

  3. Investigation of micro-structural phenomena at aggregate level in concretes using DEM

    Science.gov (United States)

    Nitka, Michał; Tejchman, Jacek

    2017-06-01

    This paper presents numerical analyses of concrete beams under three-point bending. The discrete element methods (DEM) was used to calculate fracture at the aggregate level. Concrete was described as a four-phase material, which was composed of aggregate, cement matrix, interfacial transitional zones (ITZs) and macro-voids. The beam micro-structure was directly taken from our experiments using x-ray micro-tomography. Simulations were carried out with real aggregate modelled as sphere clusters. Numerical results were compared with laboratory outcomes. The special attention was laid on the fracture propagation and some micro-structural phenomena at the aggregate level.

  4. DEM L241, A SUPERNOVA REMNANT CONTAINING A HIGH-MASS X-RAY BINARY

    Energy Technology Data Exchange (ETDEWEB)

    Seward, F. D. [Smithsonian Astrophysical Observatory, 60 Garden Street, Cambridge, MA 02138 (United States); Charles, P. A. [School of Physics and Astronomy, University of Southampton, Highfield, Southampton SO17 1BJ (United Kingdom); Foster, D. L. [South African Astronomical Observatory, P.O. Box 9, Observatory 7935, Cape Town (South Africa); Dickel, J. R.; Romero, P. S. [Department of Physics and Astronomy, University of New Mexico, 1919 Lomas Boulevard NE, Albuquerque, NM 87131 (United States); Edwards, Z. I.; Perry, M.; Williams, R. M. [Department of Earth and Space Sciences, Columbus State University, Coca Cola Space Science Center, 701 Front Avenue, Columbus, GA 31901 (United States)

    2012-11-10

    A Chandra observation of the Large Magellanic Cloud supernova remnant DEM L241 reveals an interior unresolved source which is probably an accretion-powered binary. The optical counterpart is an O5III(f) star making this a high-mass X-ray binary with an orbital period likely to be of the order of tens of days. Emission from the remnant interior is thermal and spectral information is used to derive density and mass of the hot material. Elongation of the remnant is unusual and possible causes of this are discussed. The precursor star probably had mass >25 M {sub Sun}.

  5. A 3D DEM-LBM approach for the assessment of the quick condition for sands

    Science.gov (United States)

    Mansouri, M.; Delenne, J.-Y.; El Youssoufi, M. S.; Seridi, A.

    2009-09-01

    We present a 3D numerical model to assess the quick condition (the onset of the boiling phenomenon) in a saturated polydisperse granular material. We use the Discrete Element Method (DEM) to study the evolution of the vertical intergranular stress in a granular sample subjected to an increasing hydraulic gradient. The hydrodynamic forces on the grains of the sample are computed using the Lattice Boltzmann Method (LBM). The principal assumption used is that grains remain at rest until the boiling onset. We show that the obtained critical hydraulic gradient is close to that defined in classical soil mechanics. To cite this article: M. Mansouri et al., C. R. Mecanique 337 (2009).

  6. A expressão dos demônios de Morin

    OpenAIRE

    Maria do Socorro Veloso de Albuquerque; Kátia Rejane de Medeiros; Karla Luna; Sabrina Ribeiro de Almeida; Eronildo Felisberto

    2007-01-01

    O objetivo deste texto é promover um diálogo com a autobiografia intelectual de Edgar Morin, com os três temas de maior relevância na sua obra "Meus demônios": a epistemologia, a ética e a política; e destacar a importância do pensamento complexo no processo de produzir saúde. A postura de indagação contínua faz Morin refletir sobre a provisoriedade das "verdades" e "conclusões". Sobretudo, que o conhecimento nunca é total, mas multidimensional. Propõe-se a construir um conhecimento que relig...

  7. Analysis of compaction of railway ballast by different maintenance methods using DEM

    Science.gov (United States)

    Ferellec, Jean-Francois; Perales, Robert; Nhu, Viet-Hung; Wone, Michel; Saussine, Gilles

    2017-06-01

    Railway traffic continuously increasing, ballasted tracks need more efficient maintenance processes. Lines with long welded rails which are prone to buckling during heat waves require stabilisation before being fully operational. Stabilisation is performed either naturally using regular traffic at penalising lower speeds, dynamic stabilisation of sleepers or alternatively crib compaction. The objective of this paper is to apply the NSCD approach of DEM to simulate the processes of dynamic stabilisation and crib compaction as they are realised on site and compare their performance in terms of ballast compaction and lateral resistance. The results showed that NSCD is perfectly appropriate to simulate these maintenance processes and estimate their performance.

  8. Deep Convolutional Generative Adversarial Network for Procedural 3D Landscape Generation Based on DEM

    DEFF Research Database (Denmark)

    Wulff-Jensen, Andreas; Rant, Niclas Nerup; Møller, Tobias Nordvig

    2017-01-01

    This paper proposes a novel framework for improving procedural generation of 3D landscapes using machine learning. We utilized a Deep Convolutional Generative Adversarial Network (DC-GAN) to generate heightmaps. The network was trained on a dataset consisting of Digital Elevation Maps (DEM......) of the alps. During map generation, the batch size and learning rate were optimized for the most efficient and satisfying map production. The diversity of the final output was tested against Perlin noise using Mean Square Error [1] and Structure Similarity Index [2]. Perlin noise is especially interesting...

  9. Effects of oxygen on the re-injection characteristics of thermal water with high salinity and a high iron content; Zum Einfluss von Sauerstoff auf das Reinjektionsverhalten hochsalinarer, eisenhaltiger Thermalwaesser

    Energy Technology Data Exchange (ETDEWEB)

    Martin, M.; Koeckritz, V. [TU BA Freiberg (Germany). Inst. fuer Bohrtechnnik und Fluidbergbau; Seibt, A. [GeoForschungsZentrum PB 4.4, Neubrandenburg (Germany)

    1998-12-31

    For reasons of environmental protection and in order to maintain a constant pressure level, hydrogeothermal water must be re-injected into the reservoir after use. However, human interception in the natural fluid/rock system will change the thermodynamic parameters and also the pH and redox potential. This may cause interactions between bedrock, underground water, and the re-injected fluid and have negatives effects on injectivity. Research is going on in this field on the basis of the experience gained in geothermal heating stations in north eastern Germany. (orig.) [Deutsch] Bei einer energetischen und/oder stofflichen Nutzung hydrogeothermaler Ressourcen muessen die Waesser aus Gruenden des Umweltschutzes und der Druckerhaltung im Speicher wieder in das Reservoir verbracht werden. Durch den Eingriff in das natuerliche System Fluid/Gestein werden nicht nur thermodynamische Zustandsgroessen veraendert, sondern es sind auch pH- und Redoxpotentialaenderungen z.B. durch Gasentloesungen zu erwarten. Dies kann beim Reinjizieren zu Wechselwirkungen zwischen dem Speichergestein, dem Schichtwasser und dem injizierten Fluid fuehren, was negative Auswirkungen auf die Injektivitaetsentwicklung haben kann. Eine geeignete Methode zur Aufklaerung von Einzeleffekten und zur Abschaetzung von chemischen Wechselwirkungen stellen Kerndurchstroemungsversuche dar. Ausgangspunkt der Untersuchungen sind die Erfahrungen aus dem Betrieb Geothermischer Heizzentralen Nordostdeutschlands. (orig.)

  10. Analysis on Slope Attenuation Caused by DEM Re-sampling%DEM重采样坡度衰减分析

    Institute of Scientific and Technical Information of China (English)

    张小诺; 王宇; 白天路

    2012-01-01

    Using 1:10 000 digital topographic maps, digital elevation model (DEM) with resolution of 5 m DEM was generated, based on which DEM with resolution of 10, 20 and 40 m was re-sampled. The slopes of these DEM was calculated. Neighboring region analysis was conducted on DEM with resolution of 5 m; and the maximum value on the 10, 20 and 40 m resolution was extracted so that its difference from the slope directly extracted from DEM with corresponding resolution could be calculated for' frequency statistics. The results showed that the average of slope decreased as the resolution of DEM decreased; and the frequency of small slope increased while of large slope decreased. When DEM resolution was high, the difference concentrated in the small slopes. The lower DEM resolution, the more disperse the difference distribution curves, and concentrated in the large slope. The higher DEM resolution, the wider the profile curvature curves was, and vice versa; moreover, the curves was more concentrated and the section with higher profile curvature was seriously lost.%通过数字高程模型(DEM)重采样发现,随着水平分辨率的降低,地形也随着趋向平缓,坡度信息不断丢失,地面表达能力逐步下降.利用1∶10 000数字地形图生成5m水平分辨率DEM,以此为基准重采样生成10、20、40m水平分辨率的DEM,提取各水平分辨率DEM的坡度.对提取的5m水平分辨率DEM的坡度进行邻域分析,提取10、20、40m水平分辨率DEM的最大坡度,以此求取其与直接由相对应水平分辨率DEM提取的坡度的差值,并对坡度差值进行频率统计分析,同时分析了剖面曲率在重采样过程中的变化.结果表明,随着DEM水平分辨率的降低,坡度平均值不断降低,较小坡度的频率逐渐增大,较大坡度的频率逐渐减小.DEM水平分辨率较高时,坡度差值分布集中于较小坡度差值处,且范围集中;DEM水平分辨率越低,坡度差值分布曲线愈加分

  11. Visualizing impact structures using high-resolution LiDAR-derived DEMs: A case study of two structures in Missouri

    Science.gov (United States)

    Finn, Michael P.; Krizanich, Gary W.; Evans, Kevin R.; Cox, Melissa R.; Yamamoto, Kristina H.

    2015-01-01

    Evidence suggests that a crypto-explosive hypothesis and a meteorite impact hypothesis may be partly correct in explaining several anomalous geological features in the middle of the United States. We used a primary geographic information science (GIScience) technique of creating a digital elevation model (DEM) of two of these features that occur in Missouri. The DEMs were derived from airborne light detection and ranging, or LiDAR. Using these DEMs, we characterized the Crooked Creek structure in southern Crawford County and the Weaubleau structure in southeastern St. Clair County, Missouri. The mensuration and study of exposed and buried impact craters implies that the craters may have intrinsic dimensions which could only be produced by collision. The results show elevations varying between 276 and 348 m for Crooked Creek and between 220 and 290 m for Weaubleau structure. These new high- resolution DEMs are accurate enough to allow for precise measurements and better interpretations of geological structures, particularly jointing in the carbonate rocks, and they show greater definition of the central uplift area in the Weaubleau structure than publicly available DEMs.

  12. Finding the service you need: human centered design of a Digital Interactive Social Chart in DEMentia care (DEM-DISC).

    Science.gov (United States)

    van der Roest, H G; Meiland, F J M; Haaker, T; Reitsma, E; Wils, H; Jonker, C; Dröes, R M

    2008-01-01

    Community dwelling people with dementia and their informal carers experience a lot of problems. In the course of the disease process people with dementia become more dependent on others and professional help is often necessary. Many informal carers and people with dementia experience unmet needs with regard to information on the disease and on the available care and welfare offer, therefore they tend not to utilize the broad spectrum of available care and welfare services. This can have very negative consequences like unsafe situations, social isolation of the person with dementia and overburden of informal carers with consequent increased risk of illness for them. The development of a DEMentia specific Digital Interactive Social Chart (DEM-DISC) may counteract these problems. DEM-DISC is a demand oriented website for people with dementia and their carers, which is easy, accessible and provides users with customized information on healthcare and welfare services. DEM-DISC is developed according to the human centered design principles, this means that people with dementia, informal carers and healthcare professionals were involved throughout the development process. This paper describes the development of DEM-DISC from four perspectives, a domain specific content perspective, an ICT perspective, a user perspective and an organizational perspective. The aims and most important results from each perspective will be discussed. It is concluded that the human centered design was a valuable method for the development of the DEM-DISC.

  13. Arctic Digital Elevation Models (DEMs) generated by Surface Extraction from TIN-Based Searchspace Minimization (SETSM) algorithm from RPCs-based Imagery

    Science.gov (United States)

    Noh, M. J.; Howat, I. M.; Porter, C. C.; Willis, M. J.; Morin, P. J.

    2016-12-01

    The Arctic is undergoing rapid change associated with climate warming. Digital Elevation Models (DEMs) provide critical information for change measurement and infrastructure planning in this vulnerable region, yet the existing quality and coverage of DEMs in the Arctic is poor. Low contrast and repeatedly-textured surfaces, such as snow and glacial ice and mountain shadows, all common in the Arctic, challenge existing stereo-photogrammetric techniques. Submeter resolution, stereoscopic satellite imagery with high geometric and radiometric quality, and wide spatial coverage are becoming increasingly accessible to the scientific community. To utilize these imagery for extracting DEMs at a large scale over glaciated and high latitude regions we developed the Surface Extraction from TIN-based Searchspace Minimization (SETSM) algorithm. SETSM is fully automatic (i.e. no search parameter settings are needed) and uses only the satellite rational polynomial coefficients (RPCs). Using SETSM, we have generated a large number of DEMs (> 100,000 scene pair) from WorldView, GeoEye and QuickBird stereo images collected by DigitalGlobe Inc. and archived by the Polar Geospatial Center (PGC) at the University of Minnesota through an academic licensing program maintained by the US National Geospatial-Intelligence Agency (NGA). SETSM is the primary DEM generation software for the US National Science Foundation's ArcticDEM program, with the objective of generating high resolution (2-8m) topography for the entire Arctic landmass, including seamless DEM mosaics and repeat DEM strips for change detection. ArcticDEM is collaboration between multiple US universities, governmental agencies and private companies, as well as international partners assisting with quality control and registration. ArcticDEM is being produced using the petascale Blue Waters supercomputer at the National Center for Supercomputer Applications at the University of Illinois. In this paper, we introduce the SETSM

  14. 基于整型小波变换的DEM数据压缩%DEM Compression Based on Integer Wavelet Transform

    Institute of Scientific and Technical Information of China (English)

    陈仁喜; 李鑫慧

    2007-01-01

    DEM data is an important component of spatial database in GIS. The data volume is so huge that compression is necessary. Wavelet transform has many advantages and has become a trend in data compression. Considering the simplicity and high efficiency of the compression system, integer wavelet transform is applied to DEM and a simple coding algorithm with high efficiency is introduced. Experiments on a variety of DEM are carried out and some useful rules are presented at the end of this paper.

  15. Investigating sediment budgets and pathways using LiDAR DEMs of difference and a geomorphological map

    Science.gov (United States)

    Hilger, Ludwig; Becht, Michael; Heckmann, Tobias

    2014-05-01

    In alpine catchments sediment is moved from one landform to another as long as they are coupled by the activity of geomorphic processes. The spatial and functional interaction of these processes forms sediment cascades reaching from sediment sources or stores to sediment sinks, and ultimately to the catchment outlet. In study presented here, multitemporal high-resolution LiDAR datasets are used to establish morphological sediment budgets. These can be calculated on the raster cell scale, i.e. by differencing digital elevation models (DEM), and on the landform scale, by establishing the net balance of eroded and accumulated material; in the latter case, the spatial unit is a polygon identifying a particular landform on a detailed geomorphological map. The flow of mobilised sediment can be estimated on a DEM using a variety of flow routing algorithms, and the net balance (sediment eroded - sediment deposited) is accumulated along specific pathways. The results of landform-based sediment budgets can be used to validate the flow routing algorithms and to assess functional connectivity between landforms that are arranged along a toposequence. Graph theory is used to store and investigate resulting sediment pathways on different aggregation levels. The incorporation of the geomorphological map highlights potential advantages of object-based over pixel-based approaches to generating graph nodes and analysing sediment cascades.

  16. Comparison Between Topographic Expression of RADARSAT and DEM in Simpang Pulai to Pos Selim, Malaysia

    Directory of Open Access Journals (Sweden)

    M.F.Ramli

    2010-01-01

    Full Text Available Radar and digital elevation model had been utilised in many structural studies. The main objective of this study is to compare the RADARSAT and digital elevation model for lineament interpretation which probably represent the main joints or faults along the Simpang Pulai to Pos Selim highway, Malaysia. These joints and faults may influence the instability along the highway. Manual comparison in terms of topographical aspect was undertaken between RADARSAT with 25 m spatial resolution and digital elevation model derived from 20 m contour interval of the topographical map. The previously interpreted lineaments of more than 2 km in the study area was draped over the RADARSAT and digital elevation model to compared whether the lineament concurred with the topographical representation. The interpreted lineaments were derived from Landsat TM of 1990 and 2002, where the DEM had been utilised in the negative lineament determination. It is concluded that the application RADARSAT is not very useful in terms of topographical expression in the structural geological interpretation for the study area compared to DEM derived from contour data. Further work is suggested before any conclusion can be confidently derived.

  17. Hydrological modeling using high resolution dem to level control on highways

    Science.gov (United States)

    Akbulut, Zeynep; Cömert, Çetin

    2016-04-01

    Floods are natural disasters that must be managed, controlled and taken precautions before it happens considering the damage they inflicted to environment and human lives. As to highways, the main vein of urban life flow, must be taken into consideration as a different entity that affected by excessive rainfalls and floods. Due to inadequate drainage that allow rainfall to form water ponds on highways cause vehicles to lose control and that lead vehicles to have traffic accidents. To reduce the traffic accidents caused by ponding waters on highways we need to know area of inundation and water depths. In this context we used FLO-2D Basic Model (2009) to hydrological modeling of Black Sea Coastal Highway with meteorological and hydrological data using a Digital Elevation Model (DEM). In this study, ponding areas on highways determined by simulating the rainfall with a high resolution DEM that can represent the actual road surface correctly. With this information, General Directorate of Highways (GDH) in Turkey can adjust the cross-sectional and longitudinal slope or build better and bigger drainage structures where water accumulated to prevent ponding. With the results obtained from Hydrological Model, GDH can rapidly control highways conformity to regulations before highways come into service. Also these ponding areas acquired by reveals where to prioritize in flood risk managements. Key Words: Area of Inundation, Digital Elevation Model, FLO-2D, Hydrological Modeling, Highway, Rainfall-Runoff Simulation, Water Depth.

  18. Investigating mixing and segregation using discrete element modelling (DEM) in the Freeman FT4 rheometer.

    Science.gov (United States)

    Yan, Zilin; Wilkinson, Sam K; Stitt, Edmund H; Marigo, Michele

    2016-11-20

    Mixing and segregation in a Freeman FT4 powder rheometer, using binary mixtures with varied particle size ratio and volume fraction, were studied using the Discrete Element Method (DEM). As the blade moves within the particle bed, size induced segregations can occur via a sifting mechanism. A larger particle size ratio and/or a larger volume fraction of large particles lead to a quicker segregation process. A higher particle velocity magnitude can promote the segregation process and the rate for the segregation index increases in the radial direction: from the centre towards the outer layer. In the current DEM simulations, it is shown that the change in flow energy associated with segregation and mixing depends on the choice of frictional input parameters. FT4 is proposed as a potential tool to compare and rank the segregation tendency for particulate materials with distinct differences in flow energy of each component. This is achieved by measuring the flow energy gradient after a number of test cycles for mixing powders with different flow properties. Employing the FT4 dynamic powder characterisation can be advantageous to establish blending performances in an industrial context.

  19. Effect of cohesion on granular-fluid flows in spouted beds: PIV measurement and DEM simulations

    Science.gov (United States)

    Zhu, Runru; LI, Shuiqing; Yao, Qiang

    2013-06-01

    In contrast to wet granular flows, the effect of cohesion on complex granular-fluid flows is intriguing but much challenging. The liquid bridges, forming between binary particles with the addition of a small amount of liquids, might significantly change the granular-fluid system due to both cohesion and lubrication effects. In this paper, a spouted bed, among various fluidization technologies, is particularly selected as a prototypical system for studying granular-fluid flows, since it can provide a quasi-steady flow pattern of granular particles, i.e., a core of upward granular-fluid flow called the "spout" and a surrounding region of downward quasi-static granular flow called the "annulus". Firstly, using self-developed particle image velocimetery (PIV) technique, the effects of cohesion on the spout-annulus interface (namely the spout width) and on the particle velocity profiles in distinct zones are examined. Further, the discrete element method (DEM), by incorporating liquid bridge adhesion into soft-sphere model, is established and used to predict the microdynamic behavior of particles in spouted beds. Finally, based on both experiments and DEM validation, the effects on the granular patterns in these two zones are comparatively discussed.

  20. Erstnachweis von Taiwania, Cryptomeria und Liquidambar aus dem Bitterfelder und Baltischen Bernstein

    Directory of Open Access Journals (Sweden)

    H. Jähnichen

    1998-01-01

    Full Text Available Aus dem untermiozänen Bernstein von Bitterfeld (Sachsen-Anhalt werden erstmalig ein strukturzeigender Zweig von Taiwania schaeferi, ein isoliertes Nadel-Fragment von Cryptomeria sp. sowie ein Fruchtstand von Liquidambar europaea beschrieben. Außerdem muß “Widdringtonites oblongifolius” (Goeppert & Menge Caspary & Klebs 1906/07 pro parte aus dem obereozänen Baltischen Bernstein nach morphologisch-anatomischen Merkmalskomplexen ebenfalls zu Taiwania schaeferi gestellt werden. “Enormicutis eoconferta” — aff. Cryptomeria spec. (Schneider 1986 aus der obereozänen Braunkohle von Nordwestsachsen muß nach morphologisch-anatomischen Details zu Athrotaxis couttsiae (Heer Gardner revidiert werden. First record of Taiwania, Cryptomeria and Liquidambar from Bitterfeld and Baltic amber A structure-bearing twig of Taiwania schaeferi, an isolated needle-fragment of Cryptomeria spec. as also an aggregate fruit of Liquidambar europaea are firstly described from the Lower Miocene amber of Bitterfeld (Saxony-Anhalt. Moreover “Widdringtonites oblongifolius” (Goeppert & Menge Caspary & Klebs 1906/07 p.p. from the Upper Eocene Baltic amber after morphological-anatomical features must be also assigned to Taiwania schaeferi. “Enormicutis eoconferta” — aff. Cryptomeria sp. (Schneider 1986 from the Upper Eocene brown-coal of North Western Saxony after morphological-anatomical details must be revised to Athrotaxis couttsiae (Heer Gardner. doi:10.1002/mmng.19980010112

  1. Interferometric SAR Coherence Models for Characterization of Hemiboreal Forests Using TanDEM-X Data

    Directory of Open Access Journals (Sweden)

    Aire Olesk

    2016-08-01

    Full Text Available In this study, four models describing the interferometric coherence of the forest vegetation layer are proposed and compared with the TanDEM-X data. Our focus is on developing tools for hemiboreal forest height estimation from single-pol interferometric SAR measurements, suitable for wide area forest mapping with limited a priori information. The multi-temporal set of 19 TanDEM-X interferometric pairs and the 90th percentile forest height maps are derived from Airborne LiDAR Scanning (ALS, covering an area of 2211 ha of forests over Estonia. Three semi-empirical models along with the Random Volume over Ground (RVoG model are examined for applicable parameter ranges and model performance under various conditions for over 3000 forest stands. This study shows that all four models performed well in describing the relationship between forest height and interferometric coherence. Use of an advanced model with multiple parameters is not always justified when modeling the volume decorrelation in the boreal and hemiboreal forests. The proposed set of semi-empirical models, show higher robustness compared to a more advanced RVoG model under a range of seasonal and environmental conditions during data acquisition. We also examine the dynamic range of parameters that different models can take and propose optimal conditions for forest stand height inversion for operationally-feasible scenarios.

  2. DEM-based Modeling at the Hillslope Scale: Recent Results and Future Process Research Needs

    Science.gov (United States)

    McDonnell, J.; Coles, A.; Gabrielli, C. P.; Appels, W. M.; Ameli, A.

    2015-12-01

    Hillslope scale patterns of overland flow, infiltration, subsurface stormflow and groundwater recharge are all topographically mediated. However, the mechanisms by which macro-, meso- and micro-topographies control filling and spilling of lateral flow, and vertical infiltration, are still poorly understood. Here we present high-resolution DEMs derived from ground-based LiDAR, airborne LiDAR, and GPR (ground penetrating rebar!) with model analysis to examine the topographic controls on water flow at three distinct hillslopes. We explore surface topographic effects on rainfall- and snowmelt-infiltration and overland flow on the Canadian Prairies; the surface and subsurface topographic controls on lateral subsurface stormflow generation and groundwater recharge at a steep, wet temperate rainforest in New Zealand; and subsurface topographic controls on patterns of groundwater recharge at a forested hillslope on the Georgia Piedmont in the United States. We demonstrate how these studies reveal future research needs for improving DEM-based watershed delineation and modeling along with some surprising similarities between topographic controls on soil surface infiltration and overland flow and twin subsurface processes at the soil-bedrock interface.

  3. Magnetisches Tracking für die Navigation mit dem da Vinci® Surgical System

    Science.gov (United States)

    Nickel, Felix; Wegner, Ingmar; Kenngott, Hannes; Neuhaus, Jochen; Müller-Stich, Beat P.; Meinzer, Hans-Peter; Gutt, Carsten N.

    In dieser Studie wurde untersucht ob in einem typischen OP-Aufbau mit dem da Vinci® Telemanipulator elektromagnetisches Tracking für die Realisation eines Navigationssystems eingesetzt werden kann. Hierfür wurde in einem realen OP-Aufbau untersucht, wie stark metallische und ferromagnetisch wirksame Objekte wie Operationstisch und Telemanipulator das elektromagnetische Feld des Trackingsystems beeinflussen. Die Ergebnisse zeigen, dass der Telemanipulator nur unwesentlich die Störung des Magnetfeldes durch den OP-Tisch verstärkt. Insbesondere die Bewegung der Instrumente im Trackingvolumen verursachte keine zusätzliche relevante Störung des Magnetfeldes. Bei Begrenzung des Trackingvolumens auf eine Länge von 190 mm, Höhe von 200mm und Breite von 400 mm war der maximale Fehler in diesem Bereich an allen Messpunkten kleiner 10 mm. Der Einsatz von elektromagnetischem Tracking für die Navigation mit dem da Vinci® Surgical System ist somit in einem begrenzten Arbeitsvolumen mit hinreichender Genauigkeit möglich.

  4. Accuracy Improvement of ASTER Stereo Satellite Generated DEM Using Texture Filter

    Institute of Scientific and Technical Information of China (English)

    Mandla V. Ravibabu; Kamal Jain; Surendra Pal Singh; Naga Jyothi Meeniga

    2010-01-01

    The grid DEM (digital elevation model) generation can be from any of a number of sources: for instance, analogue to digital conversion of contour maps followed by application of the TIN model, or direct elevation point modelling via digital photogrammetry applied to airborne images or satellite images. Currently, apart from the deployment of point-clouds from LiDAR data acquisition, the generally favoured approach refers to applications of digital photogrammetry. One of the most important steps in such deployment is the stereo matching process for conjugation point (pixel) establishment: very difficult in modelling any homogenous areas like water cover or forest canopied areas due to the lack of distinct spatial features. As a result, application of automated procedures is sure to generate erroneous elevation values. In this paper, we present and apply a method for improving the quality of stereo DEMs generated via utilization of an entropy texture filter. The filter was applied for extraction of homogenous areas before stereo matching so that a statistical texture filter could then be applied for removing anomalous evaluation values prior to interpolation and accuracy assessment via deployment of a spatial correlation technique. For exemplification, we used a stereo pair of ASTER 1B images.

  5. A hybrid DEM/CFD approach for solid-liquid flows

    Institute of Scientific and Technical Information of China (English)

    QIU Liu-chao; WU Chuan-yu

    2014-01-01

    A hybrid scheme coupling the discrete element method (DEM) with the computational fluid dynamics (CFD) is developed to model solid-liquid flows. Instead of solving the pressure Poisson equation, we use the compressible volume-averaged continuity and momentum equations with an isothermal stiff equation of state for the liquid phase in our CFD scheme. The motion of the solid phase is obtained by using the DEM, in which the particle-particle and particle-wall interactions are modelled by using the theoretical contact mechanics. The two phases are coupled through the Newton’s third law of motion. To verify the proposed method, the sedi-mentation of a single spherical particle is simulated in water, and the results are compared with experimental results reported in the literature. In addition, the drafting, kissing, and tumbling (DKT) phenomenon between two particles in a liquid is modelled and rea-sonable results are obtained. Finally, the numerical simulation of the density-driven segregation of a binary particulate suspension in-volving 10 000 particles in a closed container is conducted to show that the presented method is potentially powerful to simulate real particulate flows with large number of moving particles.

  6. TanDEM-X Across-Track Interferometry over Dry Snow Covered Terrain

    Science.gov (United States)

    Panagiotopoulou, Dimitra; Brown, Ian A.

    2016-08-01

    We analyse bistatic HH-polarised TanDEM-X interferometric synthetic aperture radar (InSAR) data acquired over winter, dry snow conditions in a sub- Arctic site in Norway. Exploiting the principles of across-track interferometry, the elevation of the scattering phase centre estimated by the phase difference between the two SAR acquisitions. Interference patterns were assessed both qualitatively and quantitatively. Clearings and forest stands, were analysed. Interferometric phase uncertainty and spatio-temporal consistency were analysed by means of scattering phase centre elevation accuracy and coherence degree, γ with respect to hydro-meteorological conditions. Clearings displayed absolute height errors of < 1 m. The sole approximation was to consider volume decorrelation effects as main source of elevation ambiguities and coherence decay. Principal Component Analysis was conducted to identify the combined influence of variables describing the radar response and scattering centre. However, the derived DEMs attained high vertical accuracy, the sub-meter height errors might relate to snowcover effects. Coherence was strongly influenced by snowpack parameters suggesting TDM coherence inversion may enable snow cover monitoring.

  7. Potentials of TanDEM-X Interferometric Data for Global Forest/Non-Forest Classification

    Science.gov (United States)

    Martone, Michele; Rizzoli, Paola; Brautigam, Benjamin; Krieger, Gerhard

    2016-08-01

    This paper presents a method to generate forest/non- forest maps from TanDEM-X interferometric SAR data. Among the several contributions which may affect the quality of interferometric products, the coherence loss caused by volume scattering represents the contribution which is predominantly affected by the presence of vegetation, and is therefore here exploited as main indicator for forest classification. Due to the strong dependency of the considered InSAR quantity on the geometric acquisition configuration, namely the incidence angle and the interferometric baseline, a multi-fuzzy clustering classification approach is used. Some examples are provided which show the potential of the proposed method. Further, additional features such as urban settlements, water, and critical areas affected by geometrical distortions (e.g. shadow and layover) need to be extracted, and possible approaches are presented as well. Very promising results are shown, which demonstrate the potentials of TanDEM-X bistatic data not only for forest identification, but, more in general, for the generation of a global land classification map as a next step.

  8. Energy Crisis in the Superbubble DEM L 192 (N 51D)

    CERN Document Server

    Cooper, R L; Chu, Y H; Chen, C H R; Dunne, B C

    2004-01-01

    Superbubbles surrounding OB associations provide ideal laboratories to study the stellar energy feedback problem because the stellar energy input can be estimated from the observed stellar content of the OB associations and the interstellar thermal and kinetic energies of superbubbles are well-defined and easy to observe. We have used DEM L 192, also known as N 51D, to carry out a detailed case study of the energy budget in a superbubble, and we find that the expected amount of stellar mechanical energy injected into the ISM, (18+-5)x10^51 ergs, exceeds the amount of thermal and kinetic energies stored in the superbubble, (6+-2)x10^51 ergs. Clearly, a significant fraction of the stellar mechanical energy must have been converted to other forms of energy. The X-ray spectrum of the diffuse emission from DEM L 192 requires a power-law component to explain the featureless emission at 1.0-3.0 keV. The origin of this power-law component is unclear, but it may be responsible for the discrepancy between the stellar e...

  9. Constructing Palaeo-DEMs in landscape evolution: example of the Geren catchment, Turkey

    Science.gov (United States)

    van Gorp, Wouter; Schoorl, Jeroen M.; Veldkamp, Tom; Maddy, Darrel; Demir, Tuncer; Aytac, Serdar

    2017-04-01

    How to reconstruct the past landscape and how does this influence your modelling results? This is an important paradigma in the soilscape and landscape evolution modelling community. Here an example of Turkey will be presented where a 300 ka LEM simulation requested to the thoroughly think about the initial landscape as an important input. What information can be used to know the morphology of a landscape 300 ka ago? The Geren catchment, a tributary of the upstream Gediz river near Kula, Turkey, has been influenced by base level changes during the Late Pleistocene and Holocene. Different lavaflows have blocked the Gediz and Geren river several times over in the timespan of the last 300 ka -200 Ka and in the recent Holocene. The heavily dissected Geren catchment shows a landscape evolution which is more complex than just a reaction on these base level changes. The steps and inputs of the palaeo DEM reconstruction will be presented and the modelling results will be presented. Keywords: Digital Elevation Model, Palaeo DEMs, Numerical modelling

  10. Late Neogene Mountain Building of Eastern Kunlun Orogen: Constrained by DEM Analysis

    Institute of Scientific and Technical Information of China (English)

    Wang An; Wang Guocan; Zhang Kexin; Xiang Shuyuan; Li Dewei; Liu Demin

    2009-01-01

    Topography, as a net result of the dynamic interaction between endogenesis and exogenesis, holds immense information on tectonic uplift, surface erosion and thus mountain building. The eastern Kunlun (昆仑) orogen, which experienced significant Late Neogene tectonic uplift and is located in an arid environment, is advantageous for morphotectonlc analysis based on well-preserved tectonic landforms. The digital elevation model (DEM) analysis was carried out for the central segment of the eastern Kunlun orogen based on shuttle radar topography mission (SRTM) data. River longitudinal profile analysis indicates that major rivers across the orogen are characterized by high river gradient indexes and intensive tectonic uplift. Differential uplift was also identified in swath-topography analysis in the studied area, which can be divided into three major tectonic-geomorphic units by orogenicstrike-parallel faults. It is indicated that the most active region is located to the south of the Xidatan (西大滩) fault with significant differential uplift. Another identified fault with differential uplift is the Middle Kuninn fault; however, the timing of which is suggested to be much older than that of the Xidatan fault. These analyses are eoneordantly supported by both field survey and studies of thermochronology, which in turn indicates that the DEM analysis bears great potential in morphotectonic analysis.

  11. Improvement of dem Generation from Aster Images Using Satellite Jitter Estimation and Open Source Implementation

    Science.gov (United States)

    Girod, L.; Nuth, C.; Kääb, A.

    2015-12-01

    The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) system embarked on the Terra (EOS AM-1) satellite has been a source of stereoscopic images covering the whole globe at a 15m resolution at a consistent quality for over 15 years. The potential of this data in terms of geomorphological analysis and change detection in three dimensions is unrivaled and needs to be exploited. However, the quality of the DEMs and ortho-images currently delivered by NASA (ASTER DMO products) is often of insufficient quality for a number of applications such as mountain glacier mass balance. For this study, the use of Ground Control Points (GCPs) or of other ground truth was rejected due to the global "big data" type of processing that we hope to perform on the ASTER archive. We have therefore developed a tool to compute Rational Polynomial Coefficient (RPC) models from the ASTER metadata and a method improving the quality of the matching by identifying and correcting jitter induced cross-track parallax errors. Our method outputs more accurate DEMs with less unmatched areas and reduced overall noise. The algorithms were implemented in the open source photogrammetric library and software suite MicMac.

  12. Multi-temporal airborne LIDAR-DEMs for glacier and permafrost mapping and monitoring

    Directory of Open Access Journals (Sweden)

    J. Abermann

    2009-07-01

    Full Text Available The proposed method presents a simple and robust way to derive glacier extent by using multi-temporal high-resolution DEMs (digital elevation models as a main data source. For glaciers that are not debris covered, we perform the glacier boundary delineation by analysing roughness differences between ice and its surroundings. A promising way to distinguish dead ice, debris-covered ice or permafrost from its rocky surroundings is shown by taking elevation changes from DEMs of different dates into consideration. In case data has a high spatial and temporal resolution a good representation of the extent of debris cover and thus the overall ice covered area can be given. We use examples to show how potentially ambiguous areas can be treated decisively by the additional qualitative analysis of aerial photographs. Problems and limitations are discussed in comparison with selected other remote sensing techniques and accuracies are quantified. For glaciers larger than 1 km2 an accuracy of ±1% of the glacier area could be assessed. The errors of smaller glaciers do not exceed ±5% of the glacier area.

  13. Tectonic development of the Northwest Bonaparte Basin, Australia by using Digital Elevation Model (DEM)

    Science.gov (United States)

    Wahid, Ali; Salim, Ahmed Mohamed Ahmed; Ragab Gaafar, Gamal; Yusoff, AP Wan Ismail Wan

    2016-02-01

    The Bonaparte Basin consist of majorly offshore part is situated at Australia's NW continental margin, covers an area of approx. 270,000km2. Bonaparte Basin having a number of sub-basins and platform areas of Paleozoic and Mesozoic is structurally complex. This research established the geologic and geomorphologic studies using Digital Elevation Model (DEM) as a substitute approach in morphostructural analysis to unravel the geological complexities. Although DEMs have been in practice since 1990s, they still have not become common tool for mapping studies. The research work comprised of regional structural analysis with the help of integrated elevation data, satellite imageries, available open topograhic images and internal geological maps with interpreted seismic. The structural maps of the study area have been geo-referenced which further overlaid onto SRTM data and satellite images for combined interpretation which facilitate to attain Digital Elevation Model of the study area. The methodology adopts is to evaluate and redefine development of geodynamic processes involved in formation of Bonaparte Basin. The main objectives is to establish the geological histories by using digital elevation model. The research work will be useful to incorporate different tectonic events occurred at different Geological times in a digital elevation model. The integrated tectonic analysis of different digital data sets benefitted substantially from combining them into a common digital database. Whereas, the visualization software facilitates the overlay and combined interpretation of different data sets which is helpful to reveal hidden information not obvious or accessible otherwise for regional analysis.

  14. A Detailed Observation of a LMC Supernova Remnant DEM L241 with XMM-Newton

    CERN Document Server

    Bamba, A; Nakajima, H; Mori, K; Koyama, K; Bamba, Aya; Ueno, Masaru; Nakajima, Hiroshi; Mori, Koji; Koyama, Katsuji

    2006-01-01

    We report on an {\\it XMM-Newton} observation of the supernova remnant (SNR) \\object{DEM L241} in the Large Magellanic Cloud. In the soft band image, the emission shows an elongated structure, like a killifish, with a central compact source. The compact source is point-like, and named as XMMU J053559.3$-$673509. The source spectrum is well reproduced with a power-law model with a photon index of $\\Gamma = 1.57$ (1.51--1.62) and the intrinsic luminosity is $2.2\\times 10^{35} \\mathrm{ergs s^{-1}}$ in the 0.5--10.0 keV band, with the assumed distance of 50 kpc. The source has neither significant coherent pulsations in $2.0\\times 10^{-3}$ Hz--8.0 Hz, nor time variabilities. Its luminosity and spectrum suggest that the source might be a pulsar wind nebula (PWN) in DEM L241. The spectral feature classifies this source into rather bright and hard PWN, which is similar to those in Kes 75 and B0540$-$693. The elongated diffuse structure can be divided into a ``Head'' and ``Tail'', and both have soft and line-rich spect...

  15. CFD-DEM simulation of a conceptual gas-cooled fluidized bed nuclear reactor

    Energy Technology Data Exchange (ETDEWEB)

    Almeida, Lucilla C.; Su, Jian, E-mail: lucillalmeida@gmail.com, E-mail: sujian@nuclear.ufrj.br [Coordenacao dos Programas de Pos-Graduacao (COPPE/UFRJ), Rio de Janeiro, RJ (Brazil). Programa de Engenharia Nuclear; Aguirre, Joao, E-mail: aguirre@rocky-dem.com [Engineering Simulation and Scientific Software (ESSS), Rio de Janeiro, RJ (Brazil)

    2015-07-01

    Several conceptual designs of the fluidized-bed nuclear reactor have been proposed due to its many advantages over conventional nuclear reactors such as PWRs and BWRs. Amongst their characteristics, the enhanced heat transfer and mixing enables a more uniform temperature distribution, reducing the risk of hot-spot and excessive fuel temperature, in addition to resulting in a higher burnup of the fuel. Furthermore, the relationship between the bed height and reactor neutronics turns the coolant flow rate control into a power production mechanism. Moreover, the possibility of removing the fuel by gravity from the movable core in case of a loss-of-cooling accident increases its safety. High-accuracy modeling of particles and coolant flow in fluidized bed reactors is needed to evaluate reliably the thermal-hydraulic efficiency and safety margin. The two-way coupling between solid and fluid can account for high-fidelity solid-solid interaction and reasonable accuracy in fluid calculation and fluid-solid interaction. In the CFD-DEM model, the particles are modeled as a discrete phase, following the DEM approach, whereas the fluid flow is treated as a continuous phase, described by the averaged Navier-Stokes equations on a computational cell scale. In this work, the coupling methodology between Fluent and Rocky is described. The numerical approach was applied to the simulation of a bubbling fluidized bed and the results were compared to experimental data and showed good agreement. (author)

  16. Multi-frequency study of DEM L299 in the Large Magellanic Cloud

    CERN Document Server

    Warth, Gabriele; Kavanagh, Patrick J; Filipović, Miroslav D; Points, Sean D; Bozzetto, Luke M

    2014-01-01

    We have studied the HII region DEM L299 in the Large Magellanic Cloud to understand its physical characteristics and morphology in different wavelengths. We performed a spectral analysis of archived XMM-Newton EPIC data and studied the morphology of DEM L299 in X-ray, optical, and radio wavelengths. We used H alpha, [SII], and [OIII] data from the Magellanic Cloud Emission Line Survey and radio 21 cm line data from the Australia Telescope Compact Array (ATCA) and the Parkes telescope, and radio continuum data from ATCA and the Molonglo Synthesis Telescope. Our morphological studies imply that, in addition to the supernova remnant SNR B0543-68.9 reported in previous studies, a superbubble also overlaps the SNR in projection. The position of the SNR is clearly defined through the [SII]/H alpha flux ratio image. Moreover, the optical images show a shell-like structure that is located farther to the north and is filled with diffuse X-ray emission, which again indicates the superbubble. Radio 21 cm line data show ...

  17. DEM study of granular flow around blocks attached to inclined walls

    Science.gov (United States)

    Samsu, Joel; Zhou, Zongyan; Pinson, David; Chew, Sheng

    2017-06-01

    Damage due to intense particle-wall contact in industrial applications can cause severe problems in industries such as mineral processing, mining and metallurgy. Studying the flow dynamics and forces on containing walls can provide valuable feedback for equipment design and optimising operations to prolong the equipment lifetime. Therefore, solids flow-wall interaction phenomena, i.e. induced wall stress and particle flow patterns should be well understood. In this work, discrete element method (DEM) is used to study steady state granular flow in a gravity-fed hopper like geometry with blocks attached to an inclined wall. The effects of different geometries, e.g. different wall angles and spacing between blocks are studied by means of a 3D DEM slot model with periodic boundary conditions. The findings of this work include (i) flow analysis in terms of flow patterns and particle velocities, (ii) force distributions within the model geometry, and (iii) wall stress vs. model height diagrams. The model enables easy transfer of the key findings to other industrial applications handling granular materials.

  18. Soil properties and environmental tracers: A DEM based assessment in an Australian Mediterranean environment

    Science.gov (United States)

    Hancock, G. R.; Murphy, D. V.; Li, Y.

    2013-02-01

    Terrain properties vary at the hillslope and catchment scale and play a significant role in the distribution of water and sediment. Of particular interest in recent years has been the role of hillslope and catchment properties in the spatial and temporal distribution of soil organic carbon (SOC) and the ability to predict SOC from DEM terrain analysis. SOC plays a significant role in soil health and productivity as well as providing a significant store of terrestrial carbon. This study examined SOC concentration along representative pasture transects in a catchment located in southern Western Australia with a Mediterranean climate. Results demonstrate that the majority of SOC (%) is located in the near-surface (300 mm) and is concentrated in the top 0.2 m. There was no relationship found between SOC (or microbial biomass) and topography or topographic derivatives such as wetness and terrain indices from DEMs. Significant relationships were however found between SOC and environmental tracers (137Cs and 210Pbex) down the soil profile. Weak, yet significant, relationships were found between SOC and the environmental tracers along the hillslope transects, suggesting that organic carbon moves along the same pathways as clay particles in soil. An erosion assessment using 137Cs and also a numerical soil erosion and landscape evolution model found low and comparable erosion rates at the site. The results demonstrate that SOC concentration is relatively uniform across the study site and that a transect scale assessment can provide a measure of hillslope and catchment scale SOC in this environment.

  19. Satisfação sexual na demência Sexual satisfaction in dementia

    Directory of Open Access Journals (Sweden)

    Marcela Moreira Lima Nogueira

    2013-01-01

    Full Text Available CONTEXTO: A demência pode resultar em comprometimento da intimidade e sexualidade de casais idosos. OBJETIVOS: Avaliar alterações na atividade sexual, bem como os fatores de satisfação e/ou insatisfação sexual de casais nos quais um dos parceiros possua demência. MÉTODO: Busca nas bases de dados ISI, PubMed/Medline e SciELO de artigos sobre sexualidade na demência, entre janeiro de 1990 e março de 2012, utilizando as palavras-chave: "demência", "satisfação sexual", "intimidade" e "sexualidade". RESULTADOS: Foram encontrados 12 artigos. A sobrecarga de cuidados e a alteração de papéis na relação conjugal foram consideradas as principais causas para o declínio da atividade sexual. A disfunção erétil em pacientes e cônjuges, a capacidade decisória para o consentimento da relação sexual por parte do paciente demenciado e os problemas referentes à idade e à saúde (física e emocional do cônjuge e/ou paciente foram os fatores associados à insatisfação sexual. CONCLUSÃO: A intimidade e a atividade sexual dos casais em que um dos parceiros é portador de demência são influenciadas negativamente pela relação de cuidados decorrente da doença e pela sobrecarga dos cônjuges. Por outro lado, a atividade sexual pode ser positivamente substituída por demonstrações de carinho e empatia entre os cônjuges.BACKGROUND: Dementia may result on impairment in intimacy and sexuality of elderly couples. OBJECTIVES: Evaluate changes in sexual activity, as well as the factors which cause sexual satisfaction and/or dissatisfaction in couples in which one of the partners has dementia. METHOD: A search at ISI, PubMed/Medline and SciELO was made for articles about sexuality in dementia, from January 1990 to March 2012, using the keywords: "dementia", "sexual satisfaction", "intimacy" and "sexuality". RESULTS: Twelve articles were selected. The burden of care and the change of roles in couples' relationship were the main reasons for

  20. Validation of DEM modeling of sintering using an in situ X-ray microtomography analysis of the sintering of NaCl powder

    Science.gov (United States)

    Martin, Sylvain; Navarro, Sebastián; Palancher, Hervé; Bonnin, Anne; Léchelle, Jacques; Guessasma, Mohamed; Fortin, Jérôme; Saleh, Khashayar

    2016-11-01

    This paper aims to validate the discrete element method (DEM) model of sintering. In situ X-ray microtomography experiments have been carried out at the ESRF to follow the sintering of NaCl powder, the properties of which are close to the DEM model assumptions. DEM simulations are then run using an improved implicit method. The comparison between experiment and simulation shows the capability of DEM to predict the behavior of the sample on both particle and packing scale. The main advantages and limits of this approach are finally discussed based on these results and those of previous studies.

  1. High-resolution digital elevation models from single-pass TanDEM-X interferometry over mountainous regions: A case study of Inylchek Glacier, Central Asia

    Science.gov (United States)

    Neelmeijer, Julia; Motagh, Mahdi; Bookhagen, Bodo

    2017-08-01

    This study demonstrates the potential of using single-pass TanDEM-X (TDX) radar imagery to analyse inter- and intra-annual glacier changes in mountainous terrain. Based on SAR images acquired in February 2012, March 2013 and November 2013 over the Inylchek Glacier, Kyrgyzstan, we discuss in detail the processing steps required to generate three reliable digital elevation models (DEMs) with a spatial resolution of 10 m that can be used for glacial mass balance studies. We describe the interferometric processing steps and the influence of a priori elevation information that is required to model long-wavelength topographic effects. We also focus on DEM alignment to allow optimal DEM comparisons and on the effects of radar signal penetration on ice and snow surface elevations. We finally compare glacier elevation changes between the three TDX DEMs and the C-band shuttle radar topography mission (SRTM) DEM from February 2000. We introduce a new approach for glacier elevation change calculations that depends on the elevation and slope of the terrain. We highlight the superior quality of the TDX DEMs compared to the SRTM DEM, describe remaining DEM uncertainties and discuss the limitations that arise due to the side-looking nature of the radar sensor.

  2. Investigations into the acceleration of microbial degradation of PAH in soils with high PAH contamination by coffein in practical conditions. Central analytical procedure and microbial effects; Untersuchungen zur Beschleunigung des mikrobiellen Abbaus von polycyclischen aromatischen Kohlenwasserstoffen in Boeden mit hoher PAH-Kontamination durch Coffein unter Praxisbedingungen. Teilprojekt A und B. Zentrale Analytik und mikrobiologische Begleituntersuchungen. Entwicklung einer optimalen Anwendungstechnik sowie oekonomische Evaluierung in Relation zu bestehenden Verfahren. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Grimmer, G.; Collins, H.J.; Muennich, K.

    1998-01-01

    PAH degradation by Mucor circinelloides was proved several times in the course of this project. Although PAH contamination could never be completely removed, a number of parameters were identified that influence successful PAH degradation, e.g. soil homogeneity, oxygen supply to the microorganisms, pH, and nutrient supply. The effect of the complexing agent coffein on PAH degradation, which had been described already in preliminary investigations, was validated several times. Optimisation experiments showed that the pre-determined optimum coffein concentration of 0.3% in the nutrient broth provided the best results also in the present investigation. There was no suggestion of a negative effect of various cations on the growth of Mucor circinelloides which may be mobilized in the soils by the acid nutrient broth. (orig./SR) [Deutsch] Im Rahmen dieses Projektes konnte der Abbau von PAH durch Mucor circinelloides mehrfach nachgewiesen werden. Es wurde in keinem Fall eine vollstaendige Entfernung der PAH-Kontamination erreicht, jedoch stellten sich eine Reihe von Parametern als wesentlich fuer einen erfolgreichen PAH-Abbau heraus (Homogenitaet des Bodenmaterials, Versorgung der Mikroorganisme mit Sauerstoff, pH-Wert, Naehrstoffversorgung). Der bereits in Voruntersuchungen beschriebene Effekt des Komplexbildners Coffein auf den PAH-Abbau wurde bei den durchgefuehrten Untersuchungen mehrfach bestaetigt. Optimierungsexperimente fuehrten zu dem Ergebnis, dass die bereits als optimal ermittelte Coffeinkonzentration von 0,3% im Naehrmedium auch fuer die hier untersuchten Boeden die besten Ergebnisse liefert. Ein negativer Einfluss verschiedener Kationen auf das Wachstum von Mucor circinelloides, die durch das saure Naehrmedium eventuell in den Boeden mobilisiert werde, war nicht festzustellen. Der Vergleich der PAH-Restgehalte nach dem mikrobiellen PAH-Abbau bei dem Modellboden `teerpechdotierter Quarzsand` und dem Boden `Gaswerk` zeigt, dass je nach untersuchtem

  3. Energy conservation with alternative `silent` (passive) cooling systems in office buildings and energetic evaluation of cold generation for `silent cooling`. German contribution to the IEA Programme ECBS Annex 28, low energy cooling. Final report; Energieeinsparung durch den Einsatz von alternativen Systemen der `stillen` (passiven) Kuehlung in Buerogebaeuden und energetische Bewertung der Kaelteerzeugung fuer die `stille Kuehlung`. Deutsche Beteiligung an dem IEA-Programm ECBS Annex 28, low energy cooling. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Laabs, K.D.; Wolkenhauer, H. [STULZ GmbH, Hamburg (Germany); Heinrich, G.; Franzke, U.; Seifert, C. [Institut fuer Luft- und Kaeltetechnik GmbH, Dresden (Germany); Steimle, F.; Mengede, B. [Essen Univ. (Gesamthochschule) (Germany). Inst. fuer Angewandte Thermodynamik und Klimatechnik

    1997-06-01

    In July 1993 a 3 years lasting research and development projekt, which deals with silent cooling systems (cold ceilings and cold beams), was started by the BMBF. During this projekt different tools, which allow the design of silent cooling systems, were developed in cooperation of the company STULZ GmbH Klimatechnik (coordination), the University of Essen and the ILK in Dresden. During this projekt different silent cooling systems were investigated in cooperation of the three organizations. These investigations were correlated with existing and available results form theoretical and practical investigations and publications. Main element of the investigated systems are cold surfaces and/or heat exchangers, which are installed in standard offices with different arrangements and forms. The heat transfer at the surfaces bases on free convection, which depends on the difference between the surfaces temperature and the air temperature inside the offices. By using water instead of air as heat distribution medium inside the building, it is possible to reduce the energy consumption in comparison to conventional air conditioning systems. Different variants of these systems were investigated under various operation parameters, so that a design tool could be developed by using the results form the investigations. (orig.) [Deutsch] Unter dem Thema: Einsatz von Systemen der `Stillen (passiven) Kuehlung` wurde im Juli 1993 ein Forschungsvorhaben mit einer Laufzeit von 3 Jahren vom BMBF gestartet. Im Rahmen dieses Forschungsvorhabens werden unter Fuehrung der Fa. STULZ GmbH Klimatechnik und in Kooperation mit der UNI Essen und des ILK Dresden verschiedene TOOLS zur Auslegung von Deckenkuehlsystemen erarbeitet. Auf der Grundlage bekannter und vorliegender theoretischer wissenschaftlicher Erkenntnisse der gebaeudebezogenen Klimatechnik sowie Veroeffentlichungen bundesdeutscher Forschungseinrichtungen und Hochschulinstitute relevanter Arbeitsbereiche wurde gemeinsam mit technischen

  4. Multi-Temporal Investigation of Greenland Ice Sheet Snow Facies Using TanDEM-X Mission Data

    Science.gov (United States)

    Rizzoli, Paola; Martone, Michele; Brautigam, Benjamin; Rott, Helmut; Moreira, Alberto

    2016-08-01

    This paper presents the first results of the developed approach for classifying Greenland ice sheet snow facies, based on the use of interferometric TanDEM-X SAR data. Large-scale mosaics of radar backscatter and volume decorrelation, derived from the interferometric coherence, are used as input data set for applying a classification algorithm based on the c-means fuzzy clustering. The unique data set provided by TanDEM-X is particularly suitable for this analysis due to the single-pass bistatic acquisition mode which does not suffer from temporal decorrelation. The obtained results have been verified with external snow melt data. Moreover, independent multi-temporal TanDEM-X backscatter data and interferometric time series have been analyzed as well.

  5. Delta-K Wideband SAR Interferometry for DEM Generation and Persistent Scatterers Using TeraSAR-X

    Science.gov (United States)

    Brcic, Ramon; Eineder, Michael; Bamler, Richard; Steinbrecher, Ulrich; Schulze, Daniel; Metzig, Robert; Papathanassiou, Konstantinos; Nagler, Thomas; Mueller, Florian; Suess, Martin

    2010-03-01

    Wideband SAR systems such as TerraSAR-X allow estimation of the absolute interferometric phase without resorting to error prone phase unwrapping. This is achieved through the delta-k technique that exploits frequency diversity within the range bandwidth to simulate a SAR system with a much longer carrier wavelength. This benefits all interferometric applications including DEM generation and land surface motion determination. Here we present the results of an ESA study (21318/07/NL/HE) into using delta-k absolute phase estimation for DEM generation and PSI (Persistent Scatterer Interferometry). Using TerraSAR- X data, examples from a delta-k DEM generation system are shown which avoid the errors induced by conventional phase unwrapping. For PSI, the possibilities of absolute phase estimation for a single PS are explored in theory and examples where wideband estimation is compared to conventional PSI processing for a stack of acquisitions over Paris.

  6. Associação entre diabetes mellitus e demência: estudo neuropatológico

    OpenAIRE

    Maria Niures Pimentel dos Santos Matioli

    2016-01-01

    A literatura científica vem debatendo sobre a existência de uma associação entre diabetes mellitus (DM) e demência, doença de Alzheimer (DA) e demência vascular (DV). O DM é um conhecido fator de risco para a doença cerebrovascular (DCV) e DV, porém não há consenso até o momento do real papel do DM no desenvolvimento das alterações neuropatológicas da DA. Objetivos: verificar a associação entre DM e demência, DM e alterações neuropatológicas da DA e DV. Métodos: os dados foram coletados do Ba...

  7. Realistic Representation of Grain Shapes in CFD--DEM Simulations of Sediment Transport: A Bonded-Sphere Approach

    CERN Document Server

    Sun, Rui

    2016-01-01

    Development of algorithms and growth of computational resources in the past decades have enabled simulations of sediment transport processes with unprecedented fidelities. The Computational Fluid Dynamics--Discrete Element Method (CFD--DEM) is one of the high-fidelity approaches, where the motions of and collisions among the sediment grains as well as their interactions with surrounding fluids are resolved. In most DEM solvers the particles are modeled as soft spheres due to computational efficiency and implementation complexity considerations, although natural sediments are usually mixture of non-spherical particles. Previous attempts to extend sphere-based DEM to treat irregular particles neglected fluid-induced torques on particles, and the method lacked flexibility to handle sediments with an arbitrary mixture of particle shapes. In this contribution we proposed a simple, efficient approach to represent common sediment grain shapes with bonded spheres, where the fluid forces are computed and applied on ea...

  8. Fibrilação atrial e demência: resultados do São Paulo ageing & health study

    OpenAIRE

    Liz Andrea Kawabata-Yoshihara; Márcia Scazufca; Itamar Souza Santos; Aristarcho Whitaker; Vitor Sérgio Kawabata; Isabela Martins Benseñor; Paulo Rossi Menezes; Paulo Andrade Lotufo

    2012-01-01

    FUNDAMENTO: A fibrilação atrial é um fator de risco controverso para demência. OBJETIVO: O objetivo deste estudo é avaliar a associação entre fibrilação atrial e demência em participantes do São Paulo Ageing & Health. MÉTODOS: O São Paulo Ageing & Health é um estudo transversal, de base populacional, de idosos residentes em um uma região de baixa renda da cidade de São Paulo, Brasil. Diagnóstico de demência foi realizado de acordo com o protocolo do grupo 10/66, com base em critérios ...

  9. Measurement of photooxidants relevant to human biometeorology in an urban agglomeration (PHOTOX). Measurement of various hydrocarbons as precursors of photooxidants relevant to human biometeorology (KOVOX). Final report of Part 2; Erfassung von human-biometeorologisch relevanten Photooxidantien in einem Ballungsraum (PHOTOX). Erfassung verschiedener Kohlenwasserstoffe als Vorlaeufersubstanzen fuer human-biometeorologisch relevante Photooxidantien (KOVOX). Abschlussbericht zum Teil 2

    Energy Technology Data Exchange (ETDEWEB)

    Jakobi, G.; Fabian, P. [eds.

    1997-04-01

    The air-chemical components ozone and PAN (peroxy acetyl nitrate), their precursors NO and NO{sub 2} and the meteorological parameters air temperature, humidity, global radiation, wind direction and wind velocity were measured in the framework of a research project (PHOTOX - Measurement of photooxidants relevant to human biometeorology in an urban agglomeration) carried out by the Department of Bioclimatology and Pollution Research. Further, a wide range of anthropogenic and biogenic hydrocarbons, which are important groups of precursors of photooxidants and potential pollution factors, were measured in the framework of another research project (KOVOX - Measurement of various hydrocarbons as precursors of photooxidants relevant to human biometeorology). (orig/SR) [Deutsch] Die Messung der luftchemischen Komponenten Ozon und PAN (Peroxiacetylnitrat), deren Vorlaeufersubstanzen Stickstoffmonoxid (NO) und Stickstoffdioxid (NO{sub 2}) sowie deren meteorologischen Parameter Lufttemperatur, Luftfeuchtigkeit, Globalstrahlung, Windrichtung und Windgeschwindigkeit wurde im Rahmen des am Lehrstuhl fuer Bioklimatologie und Immisionsforschung laufenden Forschungsvorhabens ``Erfassung von human-biometeorologisch relevanten Photooxidantien in einem Ballungsraum (PHOTOX)`` durchgefuehrt. Des weiteren erfolgte die Messung einer breiten Palette anthropogener und biogener Kohlenwasserstoffe als wichtige Gruppen der Vorlaeufersubstanzen zur Photooxidantienbildung und moeglicher Wirkfaktoren, im Rahmen des Projektes ``Erfassung verschiedener Kohlenwasserstoffe als Vorlaeufersubstanzen fuer human-biometeorologisch relevante Photooxidantien (KOVOX)``. (orig./BW)

  10. Environmental impact statements in the case of research projects - the example of photovoltaic energy conversion. Vol. 5. Environmentally relevant material balances in the prodution of different types of solar cells; Umweltvorsorgepruefung bei Forschungsvorhaben - am Beispiel von Photovoltaik. Bd. 5. Umweltrelevante Stoffstroeme bei der Herstellung verschiedener Solarzellen

    Energy Technology Data Exchange (ETDEWEB)

    Hagedorn, G.; Hellriegel, E. [Forschungsstelle fuer Energiewirtschaft, Muenchen (Germany)

    1992-06-01

    The material balances during production of different types of solar cells were analyzed in cooperation with solar cell producers. Part I of this final report contains the results for conventional processes for PV module production from multicrystalline, monocrystalline and amorphous silicon. Part II discusses the possibilities of disposal and recycling of photovoltaic modules. Research has shown that there are hardly any practicable concepts in this field; new solutions must be found if photovoltaic energy conversion is to be applied on a large scale. (orig.). [Deutsch] Die bei der Herstellung verschiedener Solarzellentypen auftretenden Stofffluesse wurden in Zusammenarbeit mit den Herstellern einer eingehenden Analyse unterzogen. Teil I des vorliegenden Endberichts enthaelt die Ergebnisse zu konventionellen Verfahren der Herstellung von PV-Modulen aus multi-, monokristallinem und amorphem Silicium. Ausserdem werden im Teil II die Entsorgungs- und Recyclingmoeglichkeiten von Photovoltaikmodulen diskutiert. Recherchen haben gezeigt, dass auf diesem Gebiet bisher kaum praktikable Konzepte existieren und hier neue Loesungswege zu erarbeiten sind, falls die Photovoltaik in groessere Produktionsvolumina wachsen wird oder soll. (orig.).

  11. Automatic Delineation of Sea-Cliff Limits Using Lidar-Derived High-Resolution DEMs in Southern California

    Science.gov (United States)

    Palaseanu, M.; Danielson, J.; Foxgrover, A. C.; Barnard, P.; Thatcher, C.; Brock, J. C.

    2014-12-01

    Seacliff erosion is a serious hazard with implications for coastal management, and is often estimated using successive hand digitized cliff tops or bases (toe) to assess cliff retreat. Traditionally the recession of the cliff top or cliff base is obtained from aerial photographs, topographic maps, or in situ surveys. Irrespective of how or what is measured to categorize cliff erosion, the position of the cliff top and cliff base is important. Habitually, the cliff top and base are hand digitized even when using high resolution lidar derived DEMs. Even if efforts were made to standardize and eliminate as much as possible any digitizing subjectivity, the delineation of cliffs is time consuming, and depends on the analyst's interpretation. We propose an automatic procedure to delineate the cliff top and base from high resolution bare-earth DEMs. The method is based on bare-earth high-resolution DEMs, generalized coastal shorelines and approximate measurements of distance between the shoreline and the cliff top. The method generates orthogonal transects and profiles with a minimum spacing equal to the DEM resolution and extracts for each profile xyz coordinates for cliff's top and toe, as well as second major positive and negative inflections (second top and toe) along the profile. The difference between the automated and digitized top and toe, respectively, is smaller than the DEM error margin for over 82% of the top points and 86% of the toe points along a stretch of coast in Del Mar, CA. The larger errors were due either to the failure to remove all vegetation from the bare-earth DEM or errors of interpretation during hand digitizing. The automatic method was further applied between Point Conception and Los Angeles Harbor, CA. This automatic method is repeatable, takes advantage of the bare-earth high-resolution, and is more efficient.

  12. The EVE plus RHESSI DEM for Solar Flares, and Implications for Residual Non-Thermal X-Ray Emission

    Science.gov (United States)

    McTiernan, James; Caspi, Amir; Warren, Harry

    2016-05-01

    Solar flare spectra are typically dominated by thermal emission in the soft X-ray energy range. The low energy extent of non-thermal emission can only be loosely quantified using currently available X-ray data. To address this issue, we combine observations from the EUV Variability Experiment (EVE) on-board the Solar Dynamics Observatory (SDO) with X-ray data from the Reuven Ramaty High Energy Spectroscopic Imager (RHESSI) to calculate the Differential Emission Measure (DEM) for solar flares. This improvement over the isothermal approximation helps to resolve the ambiguity in the range where the thermal and non-thermal components may have similar photon fluxes. This "crossover" range can extend up to 30 keV.Previous work (Caspi et.al. 2014ApJ...788L..31C) concentrated on obtaining DEM models that fit both instruments' observations well. For this current project we are interested in breaks and cutoffs in the "residual" non-thermal spectrum; i.e., the RHESSI spectrum that is left over after the DEM has accounted for the bulk of the soft X-ray emission. As in our earlier work, thermal emission is modeled using a DEM that is parametrized as multiple gaussians in temperature. Non-thermal emission is modeled as a photon spectrum obtained using a thin-target emission model ('thin2' from the SolarSoft Xray IDL package). Spectra for both instruments are fit simultaneously in a self-consistent manner.For this study, we have examined the DEM and non-thermal resuidual emission for a sample of relatively large (GOES M class and above) solar flares observed from 2011 to 2014. The results for the DEM and non-thermal parameters found using the combined EVE-RHESSI data are compared with those found using only RHESSI data.

  13. Demófilo y Menéndez Pidal: folclore y filología, tragedia y epopeya

    Directory of Open Access Journals (Sweden)

    José Manuel Pedrosa

    2017-07-01

    Full Text Available Antonio Machado y Álvarez, Demófilo, is considered the founder of the sciences of folklore and anthropology in Spain. But during his life he only suffered rejections and forgetfulness, which have remained alive, to some extent, until today. Ramón Menéndez Pidal, considered one of the founders of Spanish and Romanic philology, was, on the other hand, a highly respected figure, who had an enormous academic recognition. This article compares the two models and methods, and underscores the modernity of the method of Demófilo.

  14. Investigation of Drag Force on Fibres of Bonded Spherical Elements using a Coupled CFD-DEM Approach

    DEFF Research Database (Denmark)

    Jensen, Anna Lyhne; Sørensen, Henrik; Rosendahl, Lasse Aistrup;

    2016-01-01

    are quantified. The drag coefficient on the resolved cylinder is compared to a CFD-DEM simulation of a flexible fiber made by a chain of bonded spherical discrete elements, using a free steam drag formulation on each particle. Based on the results, a drag force model can distinguish between the outermost...... can be modelled as a multi-rigid-body system using bonded spherical DEM particles. However, the flexible objects are not resolved by the CFD mesh, and therefore modelling of fluid forces on the flexible object becomes a key issue. This study investigates the modelling of fluid forces on a rigid fiber...

  15. Klinische Ergebnisse nach stereotaktischer Präzisionsbestrahlung großer uvealer Melanome mit dem Gamma-Knife

    OpenAIRE

    Schonenbach, Sabine

    2006-01-01

    Von Juni 1997 bis April 2001 wurden 97 Patienten, die an einem unilateralen uvealen Melanom litten, mit dem Gamma-Knife radiochirurgisch behandelt. Die Melanome aller 97 Patienten waren aufgrund der Lokalisation oder der Größe für eine Therapie mit Ruthenium-Applikatoren nicht geeignet. Alle 97 Patienten, die sich der Therapie mit dem Gamma-Knife unterzogen, wurden in eine engmaschige Nachsorge aufgenommen. Bei der Nachsorge wurden in regelmäßigen Abständen klinische, echographische und n...

  16. Doença de Alzheimer: declínio funcional e estágio da demência

    OpenAIRE

    Talmelli, Luana Flávia da Silva; Vale,Francisco de Assis Carvalho do; Gratão,Aline Cristina Martins; Kusumota, Luciana; Rodrigues,Rosalina Aparecida Partezani

    2013-01-01

    OBJETIVOS: Verificar como o estágio da doença de Alzheimer se correlaciona com a capacidade funcional do idoso segundo a Medida de Independência Funcional. MÉTODOS: Trata-se de estudo observacional e transversal envolvendo idosos com diagnóstico de doença de Alzheimer e seus cuidadores. Para coleta de dados utilizou-se a Medida de Independência Funcional e a escala de Avaliação Clínica de Demência. RESULTADOS: A amostra foi composta por 67 idosos com média de idade de 79 anos. Demência grave ...

  17. High-resolution Pleiades DEMs and improved mapping methods for the E-Corinth marine terraces

    Science.gov (United States)

    de Gelder, Giovanni; Fernández-Blanco, David; Delorme, Arthur; Jara-Muñoz, Julius; Melnick, Daniel; Lacassin, Robin; Armijo, Rolando

    2016-04-01

    The newest generation of satellite imagery provides exciting new possibilities for highly detailed mapping, with ground resolution of sub-metric pixels and absolute accuracy within a few meters. This opens new venues for the analysis of geologic and geomorphic landscape features, especially since photogrammetric methods allow the extraction of detailed topographic information from these satellite images. We used tri-stereo imagery from the Pleiades platform of the CNES in combination with Euclidium software for image orientation, and Micmac software for dense matching, to develop state-of-the-art, 2m-resolution digital elevation models (DEMs) for eight areas in Greece. Here, we present our mapping results for an area in the eastern Gulf of Corinth, which contains one of the most extensive and well-preserved flights of marine terraces world-wide. The spatial extent of the terraces has been determined by an iterative combination of an automated surface classification model for terrain slope and roughness, and qualitative assessment of satellite imagery, DEM hillshade maps, slope maps, as well as detailed topographic analyses of profiles and contours. We determined marine terrace shoreline angles by means of swath profiles that run perpendicularly to the paleo-seacliffs, using the graphical interface TerraceM. Our analysis provided us with a minimum and maximum estimate of the paleoshoreline location on ~750 swath profiles, by using the present-day cliff slope as an approximation for its paleo-cliff counterpart. After correlating the marine terraces laterally we obtained 16 different terrace-levels, recording Quaternary sea-level highstands of both major interglacial and several interstadial periods. Our high-resolution Pleiades-DEMs and improved method for paleoshoreline determination allowed us to produce a marine terrace map of unprecedented detail, containing more terrace sub-levels than hitherto. Our mapping demonstrates that we are no longer limited by the

  18. Sediment micromechanics in sheet flows induced by asymmetric waves: A CFD-DEM study

    Science.gov (United States)

    Sun, Rui; Xiao, Heng

    2016-11-01

    Understanding the sediment transport in oscillatory flows is essential to the investigation of the overall sediment budget for coastal regions. This overall budget is crucial for the prediction of the morphological change of the coastline in engineering applications. Since the sediment transport in oscillatory flows is dense particle-laden flow, appropriate modeling the particle interaction is critical. Although traditional two-fluid approaches have been applied to the study of sediment transport in oscillatory flows, the approaches do not capture the interaction of the particles. The study of the motion of individual sediment particles and their micromechanics (e.g., packing and contact force) in oscillatory flows is still lacking. In this work, a parallel CFD-DEM solver SediFoam that can model the inter-particle collision is applied to study the granular micromechanics of sediment particles in oscillatory flows. The results obtained from the CFD-DEM solver are validated by using the experimental data of coarse and medium sands. The comparison with experimental results suggests that the flow velocity, the sediment flux and the net sediment transport rate predicted by SediFoam are satisfactory. Moreover, the micromechanic quantities of the sediment bed are presented in detail, including the Voronoi concentration, the coordination number, and the particle interaction force. It is demonstrated that the variation of these micromechanic quantities at different phases in the oscillatory cycle is significant, which is due to different responses of the sediment bed. To investigate the structural properties of the sediment bed, the correlation of the Voronoi volume fraction and coordination number is compared to the results from the fluidized bed simulations. The consistency in the comparison indicates the structural micromechanics of sediment transport and fluidized bed are similar despite the differences in flow patterns. From the prediction of the CFD-DEM model, we

  19. Holocene palaeoDEMs for lowland coastal and delta plain landscape reconstructions

    Science.gov (United States)

    Cohen, Kim M.; Koster, Kay; Pierik, Harm-Jan; Van der Meulen, Bas; Hijma, Marc; Schokker, Jeroen; Stafleu, Jan

    2017-04-01

    Geological mapping of Holocene deposits of coastal plains, such as that of The Netherlands can reach high resolution (dense population, diverse applied usage) and good time control (14C dating, archaeology). The next step is then to create time sliced reconstructions for stages in the Holocene, peeling of the subrecent and exposing past relief situation. This includes winding back the history of sea-level rise and delta progradation etc. etc. So far, this has mainly be done as 2D series of landscape maps, or as sea-level curve age-depth plots. In the last decade, academic and applied projects at Utrecht University, TNO Geological Survey of The Netherlands and Deltares have developed palaeoDEMs for the Dutch low lands, that are a third main way of showing coastal plain evolution. Importantly, we produce two types of palaeoDEMs: (1) geological surface mapping using deposit contacts from borehole descriptions (and scripted 3D processing techniques - e.g. Van der Meulen et al. 2013) and (2) palaeogroundwater surfaces, using sea-level and inland water-level index-points (and 3D kriging interpolations - e.g. Koster et al. 2016). The applications for the combined palaeoDEMs range from relative sea-level rise mapping and assessment of variation in rate of GIA across the coastal plain, to quantification of soft soil deformation, to analysis of pre-embankment extreme flood levels. Koster, K., Stafleu, J., & Cohen, K.M. (2016). Generic 3D interpolation of Holocene base-level rise and provision of accommodation space, developed for the Netherlands coastal plain and infilled palaeovalleys. Basin Research. DOI 10.1111/bre.12202 Van der Meulen, M.J., Doornenbal, J.C., Gunnink, J.L., Stafleu, J., Schokker, J., Vernes, R.W., Van Geer, F.C., Van Gessel, S.F., Van Heteren, S., Van Leeuwen, R.J.W. & Bakker, M.A.J. (2013). 3D geology in a 2D country: perspectives for geological surveying in the Netherlands. Netherlands Journal of Geosciences, 92, 217-241. DOI 10.1017/S0016774600000184

  20. MARE2DEM: a 2-D inversion code for controlled-source electromagnetic and magnetotelluric data

    Science.gov (United States)

    Key, Kerry

    2016-10-01

    This work presents MARE2DEM, a freely available code for 2-D anisotropic inversion of magnetotelluric (MT) data and frequency-domain controlled-source electromagnetic (CSEM) data from onshore and offshore surveys. MARE2DEM parametrizes the inverse model using a grid of arbitrarily shaped polygons, where unstructured triangular or quadrilateral grids are typically used due to their ease of construction. Unstructured grids provide significantly more geometric flexibility and parameter efficiency than the structured rectangular grids commonly used by most other inversion codes. Transmitter and receiver components located on topographic slopes can be tilted parallel to the boundary so that the simulated electromagnetic fields accurately reproduce the real survey geometry. The forward solution is implemented with a goal-oriented adaptive finite-element method that automatically generates and refines unstructured triangular element grids that conform to the inversion parameter grid, ensuring accurate responses as the model conductivity changes. This dual-grid approach is significantly more efficient than the conventional use of a single grid for both the forward and inverse meshes since the more detailed finite-element meshes required for accurate responses do not increase the memory requirements of the inverse problem. Forward solutions are computed in parallel with a highly efficient scaling by partitioning the data into smaller independent modeling tasks consisting of subsets of the input frequencies, transmitters and receivers. Non-linear inversion is carried out with a new Occam inversion approach that requires fewer forward calls. Dense matrix operations are optimized for memory and parallel scalability using the ScaLAPACK parallel library. Free parameters can be bounded using a new non-linear transformation that leaves the transformed parameters nearly the same as the original parameters within the bounds, thereby reducing non-linear smoothing effects. Data