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1

Deutsche Landesbanken: Status quo und Strategien vor dem Hintergrund des Wegfalls der Staatsgarantien  

Microsoft Academic Search

Gegenstand der Untersuchung ist die Analyse der Maßnahmen der Landesbanken, der Veränderung ihrer Rolle und von Veränderungen der Finanzbranche in Zusammenhang mit dem Wegfall der staatlichen Haftungsgarantien. Die Institute weisen deutliche Parallelen bezüglich der Stoßrichtung der ergriffenen Maßnahmen auf, stellen allerdings keine homogene Gruppe dar. Die Rolle der Landesbanken hat sich zwischen 2001 und 2005 nicht grundlegend gewandelt. Vielmehr erfüllen

Klaus Berge; Ralf Berger; Hermann Locarek-Junge

2006-01-01

2

Untersuchung von Zusammenhängen zwischen kognitiver Leistungsfähigkeit und außerhäuslichem Verhalten im Alter.  

E-print Network

??Der Zusammenhang zwischen kognitiver Leistungsfähigkeit und außerhäuslichem Verhalten (außerhäusliche Mobilität sowie Aktivität), speziell im Alter, ist ein Forschungsgebiet, das bislang kaum empirisch thematisiert wurde. In… (more)

Wettstein, Markus

2012-01-01

3

Autonomes Lernen mit dem Europäischen Sprachenportfolio für junge Erwachsene (ESP 15+) im Fremdsprachenunterricht (Deutsch-Spanisch) ; und die Lernenden wissen jetzt, was sie beim Lernen tun...?.  

E-print Network

??Die vorliegende Dissertation beschäftigt sich mit dem Konstrukt von Lernerautonomie als Forschungsgegenstand im Zusammenhang mit dem Europäischen Sprachenportfolio für junge Erwachsene (ESP 15+). Das Ziel… (more)

Bru Peral, Karin

2009-01-01

4

Wirkungsunterschiede zwischen Digitalis purpurea und Digitalis lanata  

Microsoft Academic Search

Zusammenfassung Qualitative Unterschiede zwischen Digitalis purpurea und lanata bestehen:1.hinsichtlich der Latenzzeit, die am hypodynamen Straubschen Herzen für Digitalis purpurea 3–4 mal so lang ist, als für Digitalis lanata in gleicher Konzentration.2.wird die maximale Arbeitsleistung (Minutenvolumen) des durchströmten isolierten Froschherzens durch Digitalis lanata rascher erreicht als durch Digitalis purpurea gleicher Konzentration. Die therapeutische Phase dagegen dauert bei dem mit Digitalis purpurea

Fritz Heim

1936-01-01

5

Freud und Wittgenstein im Konflikt zwischen skularem Denken und Religion  

E-print Network

, den 25. Februar 2015, 18.15h-19.30h / Hauptgebäude / Raum 120 ,,Sigmund Freuds Atheismus wurde zumFreud und Wittgenstein im Konflikt zwischen säkularem Denken und Religion Symposion mit dem, säkularem Denken und Religion entfaltet hat. Er zeigt, wie Freud in seinem Leben und Denken auf sehr

Sola, Rolf Haenni

6

Studien in dem Romanstil Otto Ludwigs  

E-print Network

in Österreich und Deutschland von August Sauer." - 1903. S. 400. Otto; Ludwig. Meyer, Richard M. "Die deutsche Literatur des neunzehnter Jahrhunderts." Schmidt, Julian. "Otto Ludwig. In seinen ''Bilder aus dem geistigen Leben'." Bd. 4., S. 150... - Essays, Excerpts, und Translations." - 1907. Studien in dem Romanstil Otto Ludwigs. Einige Sätze in Ludwigs grösstem Roman, "Zwischen Himmel und Erde", die mit offenbar willkürlicher Wortstellung auf­ gebaut sind, habefi uns zuerst auf etwas...

Trovillo, Bessie

1910-01-01

7

Unerlaubte Weitergabe von privaten Daten zwischen Android-Apps  

E-print Network

Unerlaubte Weitergabe von privaten Daten zwischen Android-Apps Analyse eines Szenarios #12;Unerlaubte Weitergabe von privaten Daten zwischen Android-Apps Abstract Malware unter Android kann Weitergabe von privaten Daten zwischen Android-Apps Inhaltsverzeichnis Inhaltsverzeichnis Glossar III

Apel, Sven

8

Kommunikation zwischen Arbeiterinnen und Larven der Honigbiene Apis mellifera.  

E-print Network

??In der vorliegenden Arbeit wurde untersucht, ob und woran Arbeiterinnen der Honigbiene (Apis mellifera) den Nahrungsbedarf einzelner Larven erkennen. Als mögliche Signale in diesem Zusammenhang… (more)

Heimken, Christina

2007-01-01

9

Introduction DEM simulations  

E-print Network

in Granular Media In Memory of Ioannis Vardoulakis EMI 2010 Conference Los Angeles, California August 8­11, 2010 Kuhn -- Aug. 9, 2010 http:// faculty.up.edu / kuhn / papers / EMI2010.pdf #12;Introduction DEM-217. Kuhn -- Aug. 9, 2010 http:// faculty.up.edu / kuhn / papers / EMI2010.pdf #12;Introduction DEM

Kuhn, Matthew R.

10

Model definition DEM summary  

E-print Network

University of Portland EMI 2012 Conference South Bend, Indiana June 18­20, 2012 National Science Foundation Grant No. NEESR-936408 Kuhn, et al. -- June 20, 2012 http:// faculty.up.edu / kuhn / papers / EMI2012 / papers / EMI2012_Undrained.pdf #12;Model definition DEM summary Simple-shear Nevada Sand Particles

Kuhn, Matthew R.

11

ASTER DEM performance  

USGS Publications Warehouse

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.

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

2005-01-01

12

Über Oxy-Ephedrine  

Microsoft Academic Search

Zusammenfassung 1.Es wird an Hand der Oxy-Ephedrine der Zusammenhang zwischen Konstitution und Wirkung in der Reihe Ephedrin — Suprarenin besprochen.2.Auf Grund der Versuchsergebnisse wird der Unterschied zwischen „sympathomimetischen und sympathikotropen” Stoffen betont.3.Die Mono-oxy-Ephedrine bilden einen Übergang von dem nur sympathomimetisch (muskulotrop) wirkenden Ephedrin zu dem rein sympathikotropen (neurotropen) Suprarenin.4.Die Stellungen der OH-Gruppen sind untereinander nicht gleichwertig; die Suprareninähnlichkeit nimmt in

O. Schaumann

1931-01-01

13

Verhaltensunterschiede zwischen europäischen Formen der Silbermöwengruppe (Larus argentatus — cachinnans — fuscus)  

Microsoft Academic Search

Zusammenfassung Der Verhaltensvergleich zwischenL. a. argentatus bzw.a. argenteus (Nordsee),L. a. michahellis (Mittelmeer) undL. fuscus (Ostsee) erbrachte formale Differenzen bezüglich der wichtigsten Rufe und einiger Stellungen und Bewegungen. Danach scheintL. a. michahellis (geltend fürcachinnans) vonL. argentatus argenteus ebenso verschieden zu sein wieL. fuscus vonargenteus. Ähnlichkeiten in Rufformen und Bewegungen wurden zwischenL. a. michahellis undL. fuscus festgestellt. Beide gelbfüßigen Formen zeigen eine

Friedrich Goethe

1963-01-01

14

The Oracle of DEM  

NASA Astrophysics Data System (ADS)

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.

Gayley, Kenneth

2013-06-01

15

Die Gleichnisse von dem Wahlverwandschaften  

E-print Network

KU ScholarWorks | The University of Kansas Pre-1923 Dissertations and Theses Collection Die Gleichnisse von dem Wahlverwandschaften 1911 by Mattie Kent This work was digitized by the KU Libraries’ Office of Scholarly Communication and Copyright...

Kent, Mattie

1911-01-01

16

Hydrologic enforcement of lidar DEMs  

USGS Publications Warehouse

Hydrologic-enforcement (hydro-enforcement) of light detection and ranging (lidar)-derived digital elevation models (DEMs) modifies the elevations of artificial impediments (such as road fills or railroad grades) to simulate how man-made drainage structures such as culverts or bridges allow continuous downslope flow. Lidar-derived DEMs contain an extremely high level of topographic detail; thus, hydro-enforced lidar-derived DEMs are essential to the U.S. Geological Survey (USGS) for complex modeling of riverine flow. The USGS Coastal and Marine Geology Program (CMGP) is integrating hydro-enforced lidar-derived DEMs (land elevation) and lidar-derived bathymetry (water depth) to enhance storm surge modeling in vulnerable coastal zones.

Poppenga, Sandra K.; Worstell, Bruce B.; Danielson, Jeffrey J.; Brock, John C.; Evans, Gayla A.; Heidemann, H. Karl

2014-01-01

17

Zur Frage der Antigengemeinschaften zwischen Brucellen und Bakterien anderer Gattungen  

Microsoft Academic Search

Zusammenfassung Untersuchungen über die Antigengemeinschaft der Brucellen mit Bakterien anderer Gattungen und Familien ergaben folgendes: Obwohl einzelne Seren von Brucellosekranken den Stamm Proteus OX 19 in niedrigen Verdünnungen agglutinierten, konnte in Brucellenimmunseren und Seren, die mit dem Proteusstamm OX 19 hergestellt worden waren, keine kreuzweise Agglutination festgestellt werden. Mit dem Salmonella-O-Antigen 30 besteht eine Antigengemeinschaft, die von Seiten der Brucellen

Wilhelm Wundt

1959-01-01

18

Discrete Element Method (DEM) Soil simulations --liquefaction  

E-print Network

Discrete Element Method (DEM) Soil simulations -- liquefaction Granular materials: Are they simple? Discrete Element Modeling of Soils as Granular Materials Matthew R. Kuhn Donald P. Shiley School http:// faculty.up.edu / kuhn / papers / DEM_Corvallis.pdf #12;Discrete Element Method (DEM) Soil

Kuhn, Matthew R.

19

Wiederbeginn nach dem Zweiten Weltkrieg  

NASA Astrophysics Data System (ADS)

Dieses Kapitel schildert zunächst die Ausgangslage für die Statistik in Deutschland nach dem Zweiten Weltkrieg: Der statistische Dienst in den Besatzungszonen musste teilweise erst aufgebaut und der statistische Unterricht an den Hochschulen wieder in Gang gebracht werden. In dieser Lage ergriff der Präsident des Bayerischen Statistischen Landesamtes, Karl Wagner, tatkräftig unterstützt von Gerhard Fürst, dem späteren Präsidenten des Statistischen Bundesamtes, die Initiative zur Neugründung der Deutschen Statistischen Gesellschaft (DStatG). Die Gründungsversammlung 1948 im München wurde zu einem Meilenstein in der Geschichte der DStatG. Ziel war es, alle Statistiker zur Zusammenarbeit anzuregen, ihre Qualifikation an das internationale Niveau heranzuführen und die Anwendung neuerer statistischer Methoden in der Praxis zu fördern. Es folgten 24 Jahre fruchtbarer Arbeit unter Karl Wagner (1948-1960) und Gerhard Fürst (1960-1972). Der Beitrag skizziert die Statistischen Wochen, die Tätigkeit der Ausschüsse und die Veröffentlichungen in dieser Zeit.

Strecker, Heinrich; Bassenge-Strecker, Rosemarie

20

Joint Attention zwischen Mutter und Kind in Abhängigkeit vom Bildungsstand der Mutter.  

E-print Network

??Seit 2004 wird im Arbeitsbereich Psychologische Diagnostik der Universität Wien an der Optimierung des Video-Beobachtungsinstruments INTAKT, welches der Erfassung der Interaktionsqualität zwischen Mutter und Kind… (more)

Leopold, Alexandra

2014-01-01

21

TES overlayed on MOLA DEM  

NASA Technical Reports Server (NTRS)

This image is TES thermal data (Orbit 222) overlayed on the MOLA DEM. The color scale is TES T18-T25, which is a cold spot index. The grey scale is MOLA elevation in kilometers. Most cold spots can be attributed to surface spectral emissivity effects. Regions that are colored black-violet-blue have near unity emissivity and are coarse grained CO2. Regions that are yellow-red are fined grained CO2. The red-white spot located approximately 300W85N is our most likely candidate for a CO2 snow storm.

1999-01-01

22

New algorithm for interferometric DEM geocoding  

NASA Astrophysics Data System (ADS)

SAR interferometry can be used to derive topographic information (DEM) on the earth surface. An operation called geocoding is necessary to translate the DEM form a range- azimuth to a latitude-longitude reference system. This paper introduces a new algorithm for geocoding interferometric DEMs based on an iterative procedure using the reference ellipsoid as the first guess, then locating each earth point on a succession of planes locally parallel to the ellipsoid. The procedure is shown to geometrically converge to the considered DEM point. Given its high accuracy, this method could be used as a precision tool for use in difficult zones.

Nico, Giovanni; Refice, Alberto; Guerriero, Luciano; Veneziani, Nicola

1997-12-01

23

DEM Construction using DInSAR  

NASA Astrophysics Data System (ADS)

A digital elevation model (DEM) is a 3D visualization of a terrain surface. It can be used in various analytical studies such as topographic feature extraction, hydrology, geomorphology and landslides analysis etc. Uttrakhand region is affected with landslides, earthquake and flash flood phenomenon. Hence this study was focused on DEM generation using Differential SAR Interferometry (DINSAR) on ALOS PALSAR dataset. Two Pass DINSAR technique involves one interferometric pair in addition with an external DEM. The external DEM was used as a reference to reduce topographic errors. The data processing steps were image co-registration, interferogram generation, interferogram flattening (Differential Interferogram), interferogram filtering, coherence map, phase unwrapping, orbital refinement and re-flattening and DEM generation. Interferogram fringes observed in forest areas were due to temporal decorrelation and the fringes in mountain regions were obtained due to topography changes (may be due to landslides in rainy season). The range of elevation in generated DEM were 132 m to 2823 m and Root Mean Square Error (RMSE) error was 36.765159 m. The generated DEM was compared with ASTER DEM and variation in height was analyzed. Atmospheric effects were not removed due to geometrical and temporal decorrelation which affect the accuracy.

Mangla, R.; Kumar, S.

2014-11-01

24

Urban DEM generation, analysis and enhancements using TanDEM-X  

NASA Astrophysics Data System (ADS)

This paper analyzes the potential of the TanDEM-X mission for the generation of urban Digital Elevation Models (DEMs). The high resolution of the sensors and the absence of temporal decorrelation are exploited. The interferometric chain and the problems encountered for correct mapping of urban areas are analyzed first. The operational Integrated TanDEM-X Processor (ITP) algorithms are taken as reference. The ITP main product is called the raw DEM. Whereas the ITP coregistration stage is demonstrated to be robust enough, large improvements in the raw DEM such as fewer percentages of phase unwrapping errors, can be obtained by using adaptive fringe filters instead of the conventional ones in the interferogram generation stage. The shape of the raw DEM in the layover area is also shown and determined to be regular for buildings with vertical walls. Generally, in the presence of layover, the raw DEM exhibits a height ramp, resulting in a height underestimation for the affected structure. Examples provided confirm the theoretical background. The focus is centered on high resolution DEMs produced using spotlight acquisitions. In particular, a raw DEM over Berlin (Germany) with a 2.5 m raster is generated and validated. For this purpose, ITP is modified in its interferogram generation stage by adopting the Intensity Driven Adaptive Neighbourhood (IDAN) algorithm. The height Root Mean Square Error (RMSE) between the raw DEM and a reference is about 8 m for the two classes defining the urban DEM: structures and non-structures. The result can be further improved for the structure class using a DEM generated with Persistent Scatterer Interferometry. A DEM fusion is thus proposed and a drop of about 20% in the RMSE is reported.

Rossi, Cristian; Gernhardt, Stefan

2013-11-01

25

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

NASA Astrophysics Data System (ADS)

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.

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

2014-10-01

26

SHADED RELIEF, HILLSHADE, DIGITAL ELEVATION MODEL (DEM), ARIZONA  

EPA Science Inventory

Shaded relief of the state of Arizona developed from 1-degree US Geological Survey (USGS) Digital Elevation Models (DEMs). DEM is a terminology adopted by the USGS to describe terrain elevation data sets in a digital raster form. ...

27

SHADED RELIEF, HILLSHADE, DIGITAL ELEVATION MODEL (DEM), NEVADA  

EPA Science Inventory

Shaded relief of the state of Nevada developed from 1-degree US Geological Survey (USGS) Digital Elevation Models (DEMs). DEM is a terminology adopted by the USGS to describe terrain elevation data sets in a digital raster form. ...

28

Spracherwerb - Vergleich zwischen Kindern mit Down-Syndrom und unbeeinträchtigten Kindern unter besonderer Berücksichtigung der Syntax.  

E-print Network

??Die vorliegende Arbeit befasst sich mit dem Thema „Spracherwerb bei Down-Syndrom Kindern“. Um diesen näher zu beschreiben, erläutere ich vorerst den Spracherwerb unbeeinträchtigter Kinder um… (more)

Lischke, Nadine Catrine

2013-01-01

29

Quality assessment of TanDEM-X DEMs using airborne LiDAR, photogrammetry and ICESat elevation data  

NASA Astrophysics Data System (ADS)

TanDEM-X mission has been acquiring InSAR data to produce high resolution global DEM with greater vertical accuracy since 2010. In this study, TanDEM-X CoSSC data were processed to produce DEMs at 6 m spatial resolution for two test areas of India. The generated DEMs were compared with DEMs available from airborne LiDAR, photogrammetry, SRTM and ICESat elevation point data. The first test site is in Bihar state of India with almost flat terrain and sparse vegetation cover and the second test site is around Godavari river in Andhra Pradesh (A.P.) state of India with flat to moderate hilly terrain. The quality of the DEMs in these two test sites has been specified in terms of most widely used accuracy measures viz. mean, standard deviation, skew and RMSE. The TanDEM-X DEM over Bihar test area gives 5.0 m RMSE by taking airborne LiDAR data as reference. With ICESat elevation data available at 9000 point locations, RMSE of 5.9 m is obtained. Similarly, TanDEM-X DEM for Godavari area was compared with high resolution aerial photogrammetric DEM and SRTM DEM and found RMSE of 5.3 m and 7.5 m respectively. When compared with ICESat elevation data at several point location and also the same point locations of photogrammetric DEM and SRTM, the RMS errors are 4.1 m, 3.5 m and 4.3 m respectively. DEMs were also compared for open-pit coal mining area where elevation changes from -147 m to 189 m. X- and Y-profiles of all DEMs were also compared to see their trend and differences.

Rao, Y. S.; Deo, R.; Nalini, J.; Pillai, A. M.; Muralikrishnan, S.; Dadhwal, V. K.

2014-11-01

30

Medien zwischen Markt und Staat Hamburger Gesprche zur Transformation der Medienkultur  

E-print Network

22 REIHE 12 Medien zwischen Markt und Staat ­ Hamburger Gespräche zur Transformation der für Medi- en und Kommunikation, Universität Hamburg - Eva Hubert, Geschäftsführerin Filmförderung Hamburg/Schleswig-Holstein, Hamburg - Prof. Dr. Thomas Weber, Institut für Medien und Kommunikation

Hamburg,.Universität

31

Some DEM applications in SAR imagery  

NASA Astrophysics Data System (ADS)

With the increasing availability of SAR satellites (ERS1, ALMAZ, J-ERS, RADARSAT) along with optical remote sensing platforms (LANDSAT, SPOT), it is critical to be able to register, compare and analyze data from different sources. In this paper we will show how DEM can be used to help in these various processes in particular for SAR imagery. DEM as well as orbitographic data along with the sensor description are required to generate terrain geocoded registered products. In the case of SAR imagery these 'ancillary data' can also be used to generate by-products such as overlays, shadows, compressions and dilatations thematic maps. These maps will help in further analysis and resampling of the SAR data. Applications for improved SAR terrain geocoding as well as special radar products, SAR image interpretation and SAR interferometry will be described.

Perlant, Frederic P.

1993-09-01

32

Incorporating DEM uncertainty in coastal inundation mapping.  

PubMed

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 that convey uncertainties inherent to spatial data and analysis. PMID:25250763

Leon, Javier X; Heuvelink, Gerard B M; Phinn, Stuart R

2014-01-01

33

Das Fortpflanzungsmedizingesetz vor dem österreichischen Verfassungsgerichtshof  

Microsoft Academic Search

Zusammenfassung. Der österreichische Verfassungsgerichtshof (VfGH) hat in seinem Erkenntnis vom 14.10.1999 zur Vereinbarkeit von § 3 des österreichischen Fortpflanzungsmedizingesetzes 1992 (FMedG) mit den Artt 8 und 12 EMRK und dem Gleichheitssatz (Art 7 B-VG) Stellung genommen. Nach § 3 FMedG sind sowohl die (heterologe) künstliche Befruchtung mittels Samenspende als auch die homologe In-vitro-Fertilisation (IVF) erlaubt. Verboten sind allerdings die IVF

Brigitta Lurger

2000-01-01

34

The HELI-DEM model estimation  

NASA Astrophysics Data System (ADS)

Global DEMs are fundamental for global applications and are necessary also at the local scale, in regions where local models are not available. Local DEMs are preferred when they are available and if are characterized by better accuracies and resolutions. In general, two problems arise. Firstly, an interest region could be patched by several partly overlapping DEMs that present similar accuracies and spatial resolutions: they should be merged in a unified model. Moreover, even when the interest region is covered by one unified DEM, local DEMs with better accuracy could be available and should be used to locally improve it. All these problems have been addressed within HELI-DEM project. HELI-DEM (HELvetia-Italy Digital Elevation Model) is a project that has been funded by the European Regional Development Fund (ERDF) within the Italy-Switzerland cooperation program. It started in 2010 and finished at the end of 2013. The involved institutions in the project were Fondazione Politecnico di Milano, Politecnico di Milano, Politecnico di Torino, Regione Lombardia, Regione Piemonte and Scuola Universitaria della Svizzera Italiana. One specific aim of the project was the creation and the publication of a unified Digital Elevation Model for the part of the Alps between Italy and Switzerland. The interest area is prevalently mountainous, with heights that range from about 200 m to 4600 m. Three low Resolution DTMs (20-25-50 m of resolution) are available that partly overlap and patch the whole project area: they are characterized by accuracies of some meters. Also High Resolution DTMs (1-5 m) are available: they have accuracies of some decimeters but cover limited areas of the project. The various models are available in different reference frames (the European ETRF89 and the Italian Roma40) and are gridded either in cartographic or geographic coordinates. Before merging them, a validation of the input data has been performed in three steps: cross validation of LR DTMs, validation of LR DTMs by HR DTMs and final check by geodetic techniques. The comparisons confirm the accuracy of HR data and the presence of few local anomalies in LR DTMs. Considering the goal of the project and the previous results, two different DTMs have been produced. Both of them cover the whole project area (boundaries: ? = 7.80° East and ? = 10.70° East, ? = 45.10° North e ? = 46.70° North). They are gridded in ETRF2000 geographical coordinates and their spatial resolution is 2 × 10-4 degrees. The former has been obtained by interpolating and merging all the input LR DTMs on a new common grid. This DTM has been called HD-1. HD-1 presents the same local anomalies of the LR DTMs used as input for the interpolation: therefore, at least in areas where better data (HR DTMs) are available, its correction was needed. In order to avoid sharp discontinuities, corrections obtained by HR DTMs have been filtered by a numerical FFT approach before applying them. The result of this correction has been called HD-2. HD-1 and HD-2 have already been published by an open access geoservice.

Biagi, L.; Caldera, S.; Carcano, L.; Lucchese, A.; Negretti, M.; Sansò, F.; Triglione, D.; Visconti, M. G.

2014-04-01

35

DEM simulation of experimental dense granular packing  

SciTech Connect

In this study we present numerical analysis performed on the experimental results of sphere packings of mono-sized hard sphere whose packing fraction spans across a wide range of 0.59<{Phi}<0.72. Using X-ray Computed Tomography (XCT), we have full access to the 3D structure of the granular packings. Numerical analysis performed on thr data provides the first experimental proofs of how densification affects local order parameters. Furthermore by combining Discrete Element Method (DEM) and the experimental results from XCT, we investigate how the intergranular forces change with the onset of crystallization.

Hanifpour, Maryam; Allaei, Mehdi Vaez [Department of Physics, University of Tehran, Tehran (Iran, Islamic Republic of); Francois, Nicolas; Saadatfar, Mohammad [Department of Applied Mathematics, Research School of Physics and Engineering, Australian National University, Canberra (Australia)

2013-06-18

36

Robust methods for assessing the accuracy of linear interpolated DEM  

NASA Astrophysics Data System (ADS)

Methods for assessing the accuracy of a digital elevation model (DEM) with emphasis on robust methods have been studied in this paper. Based on the squared DEM residual population generated by the bi-linear interpolation method, three average-error statistics including (a) mean, (b) median, and (c) M-estimator are thoroughly investigated for measuring the interpolated DEM accuracy. Correspondingly, their confidence intervals are also constructed for each average error statistic to further evaluate the DEM quality. The first method mainly utilizes the student distribution while the second and third are derived from the robust theories. These innovative robust methods possess the capability of counteracting the outlier effects or even the skew distributed residuals in DEM accuracy assessment. Experimental studies using Monte Carlo simulation have commendably investigated the asymptotic convergence behavior of confidence intervals constructed by these three methods with the increase of sample size. It is demonstrated that the robust methods can produce more reliable DEM accuracy assessment results compared with those by the classical t-distribution-based method. Consequently, these proposed robust methods are strongly recommended for assessing DEM accuracy, particularly for those cases where the DEM residual population is evidently non-normal or heavily contaminated with outliers.

Wang, Bin; Shi, Wenzhong; Liu, Eryong

2015-02-01

37

DEM quality assessment for quantification of glacier surface change  

Microsoft Academic Search

Photogrammetric digital elevation models (DEMs) are often used to derive and monitor surfaces in inaccessible areas. They have been used to monitor the spatial and temporal change of glacier surfaces in order to assess glacier response to climate change. However, deriving photogrammetric DEMs of steep mountainous topography where the surface is often obscured by regions of deep shadow and snow

Addy Pope; Tavi Murray; Adrian Luckman

2007-01-01

38

DEM quality assessment for quantification of glacier surface change  

NASA Astrophysics Data System (ADS)

Photogrammetric digital elevation models (DEMs) are often used to derive and monitor surfaces in inaccessible areas. They have been used to monitor the spatial and temporal change of glacier surfaces in order to assess glacier response to climate change. However, deriving photogrammetric DEMs of steep mountainous topography where the surface is often obscured by regions of deep shadow and snow is particularly difficult. Assessing the quality of the derived surface can also be problematic, as high-accuracy ground-control points may be limited and poorly distributed throughout the modelled area. We present a method of assessing the quality of a derived surface through a detailed sensitivity analysis of the DEM collection parameters through a multiple input failure warning model (MIFWM). The variance of a DEM cell elevation is taken as an indicator of surface reliability allowing potentially unreliable areas to be excluded from further analysis. This analysis allows the user to place greater confidence in the remaining DEM. An example of this method is presented for a small mountain glacier in Svalbard, and the MIFWM is shown to label as unreliable more DEM cells over the entire DEM area, but fewer over the glacier surface, than other methods of data quality assessment. The MIFWM is shown to be an effective and easily used method for assessing DEM surface quality.

Pope, Addy; Murray, Tavi; Luckman, Adrian

2007-10-01

39

Greenland 5 km DEM, Ice Thickness, and Bedrock Elevation Grids  

NSDL National Science Digital Library

The National Snow and Ice Data Center (NSIDC) has recently released a digital elevation model (DEM), ice thickness data taken by airborne ice penetrating radar, and bedrock thickness data (ice thickness subtracted from DEM) for 5 km of Greenland. The data are in ASCII format, and documentation (data collection, application, terminology, etc.) is available at the site.

40

DIGITAL ELEVATION MODEL (DEM) FILES (30 M) FOR VIRGINIA  

EPA Science Inventory

Digital Elevation Model (DEM) files, 30-m resolution, for Virginia from US Geological Survey Web site: http://edcwww.cr.usgs.gov/doc/edchome/ndcdb/7_min_dem/states/VA.html Files listed for VA but centered in TN, WV, and NC are not included. All file archives were downloaded an...

41

TanDEM-X DEMs and feature-tracking of Helheim and Kangerdlugssuaq glaciers in south-east Greenland  

NASA Astrophysics Data System (ADS)

We use sequences of TanDEM-X acquisitions over 'supersites' Helheim and Kangerdlugssuaq glaciers in south-east Greenland to generate interferometric digital elevation models (DEMs) and to feature-track surface displacement between image acquisitions. The high spatial resolution, day/night, and cloud-penetrating capabilities of the X-band SAR system enabled the production of more than 20 DEMs for each glacier with a spatial resolution of 8 m or better. The DEMs span the period June 2011 to March 2012, at 11-day intervals, with a few breaks. Time-lapse animations of Helheim DEMs reveal the development of troughs in surface elevation close to the front. The troughs propagate down flow and develop into the rifts from which calving takes place. On both glaciers, regions of high variance in elevation can be identified caused by the transit of crevasses. In addition, on Helheim, a 1 km wide band of high variance adjacent to the calving front may be interpreted as the response to tidal forcing of a partially floating tongue. In addition to the DEMs we will also present featured tracked high-quality surface velocity fields at a spatial resolution of 2 m coincident with the DEMs. On Helheim these velocity fields indicate a winter deceleration of less than 10% at a point 4 km behind the calving front.

Bevan, Suzanne; Luckman, Adrian; Murray, Tavi

2013-04-01

42

Evaluation of Time Series TanDEM-X Digital Elevation Models  

NASA Astrophysics Data System (ADS)

Digital Elevation Model (DEM) is an important input for geo-spatial analysis. For various applications like flood management, ortho rectification of remote sensing images, navigation, architectural works, defence, etc., high resolution DEM is required. TanDEM-X mission was launched in 2010 to obtain high resolution global DEM with HTRI-3 standard. SAR interferometry (InSAR) technique is used for DEM generation from TanDEM-X SAR data. The accuracy of DEM depends on many parameters like height ambiguity, incidence angle, polarization, etc. In this study, time series TanDEM-X data spanning over 3 years, had processed for generating DEM at the spatial resolution of 6 m and their accuracy had studied using DGPS elevation data and SRTM 90 m DEM. The products generated during DEM generation process are DEM, precision (or height error), coherence, layover and shadow images. Using weighted average fusion technique, ascending and descending DEMs are fused for improving the quality of DEM and to reduce invalid pixels corresponding to layover and shadow areas. Results from time series data were analysed and found RMSE error of fused DEMs is in the range of 2 m to 4 m, while individual DEM has accuracy of 3 m to 6 m with respect to DGPS elevation data. Fused DEMs are having high accuracy as well as less voids. The reduction of voids by fusion, ranges from 40 to 85 % in different combinations of data.

Jain, M.; Deo, R.; Kumar, V.; Rao, Y. S.

2014-11-01

43

DEM Uncertainty propagation in second derivatives geomorphometrical maps  

NASA Astrophysics Data System (ADS)

In order to model the uncertainty from DEM a special model was created and implemented as Python script in ArcGIS Desktop using the ArcPy SDK provided by ESRI. The model is based on Monte Carlo simulation for generating noise and Map Algebra for adding the noise to DEM. The model can be used and independent script or combined with any other models. The inputs of the model are a DEM and an estimation of the DEM accuracy expressed as mean and standard deviation of the errors. The mean and standard deviation may be obtained from a crossvalidation/validation operation, if the model is obtained with geostatistics or by a simple validation with ground control points, if the model is obtained by other means than geostatistics. The DEM uncertainty propagation model assumes that the errors are normally distributed and thus the noise is normal distributed. This version of the model requires a Spatial Analyst extension, but the future versions may be used without or with Spatial Analyst extension. The main issue related with the addition of noise to DEM's in order to compensate for uncertainty is that the second derivatives are almost impossible to extract. This drawback was overcome by using and interpolated noisy surface in the uncertainty propagation model. Statistical analysis on raster obtained in each Monte Carlo simulation; for each realization of the model the following statistical analysis are performed: mean, minimum, maximum, range and standard deviation are extracted and saved as ESRI GRID format When the model finishes the specialist have an image about the uncertainties that might be contained by the DEM and in the same time have a collection of DEM that can be used to generate first and second order derivatives

Cosmin Sandric, Ionut; Ursaru, Petre

2013-04-01

44

Auf dem Weg DIE GOETHE-UNIVERSITT IST  

E-print Network

Studierenden gehört die Johann Wolfgang Goethe-Universität zu den zehn grö�ten Hochschulen in Deutschland wurde die Goethe-Universität von Frankfurter Bürgern gegründet. Am 1. Januar 2008 gewann sie mit derAuf dem Weg zur Spitze #12;#12;DIE GOETHE-UNIVERSIT�T IST AUF DEM WEG AN DIE SPITZE Mit 42000

45

Hallux valgus.  

E-print Network

??Intention dieser Studie war es, zu überprüfen ob es einen Zusammenhang zwischen radiologischen Aufnahmen und Fußdruckverteilungsmessungen beim Hallux valgus Winkel gibt. Diese Zusammenhänge wurden sowohl… (more)

Klein, Eva Maria

2009-01-01

46

Space Ranger Alien Quest.  

E-print Network

??Der Zusammenhang zwischen den Exekutiven Funktionen und den Autismusspektrumstörungen wird bereits seit einigen Jahrzehnten untersucht, gerät jedoch derzeit immer mehr in den Fokus des wissenschaftlichen… (more)

Schalper, Gregor

2013-01-01

47

Tanzendes Tier oder exzentrische Positionalität - Philosophische Anthropologie zwischen Darwinismus und Kulturalismus  

NASA Astrophysics Data System (ADS)

Zunächst kurz vorweg zu den Formeln im Titel: "exzentrische Positionalität“ ist der Kategorienvorschlag der Philosophischen Anthropologie (genauer: von Helmuth Plessner) für den Menschen, für seine "Sonderstellung“ unter den Lebewesen - ich werde diesen Begriff erläutern. So viel kann man sagen: Der Terminus ist nicht schwieriger als "Transzendentalität“ oder das "Apriori“ oder "Autopoiesis“, also Begriffe, mit deren Orientierungswert in der intellektuellen Öffentlichkeit bereits gespielt wird, bietet aber möglicherweise mehr Erschließungskraft als die Kunstbegriffe z. B. von Kant, Maturana oder Luhmann. Und "tanzendes Tier“ ist ein glücklicher Anschauungsbegriff, eine Art Übersetzung für "exzentrische Positionalität“ - also ein "verrücktes“ Lebewesen, eine Verrückung im evolutionären Leben, die dieses Lebewesen von Natur aus zu einer bestimmten Art von Lebensführung, nämlich Kultur nötigt. Die Absicht des Beitrages ist es, die Philosophische Anthropologie als eine spezifische Theorietechnik zu präsentieren, um einen adäquaten Begriff des Menschen zu erreichen, und zwar eine Theoriestrategie angesichts des cartesianischen Dualismus - also des Dualismus zwischen Naturalismus und Kulturalismus.

Fischer, Joachim

48

The effects of wavelet compression on Digital Elevation Models (DEMs)  

USGS Publications Warehouse

This paper investigates the effects of lossy compression on floating-point digital elevation models using the discrete wavelet transform. The compression of elevation data poses a different set of problems and concerns than does the compression of images. Most notably, the usefulness of DEMs depends largely in the quality of their derivatives, such as slope and aspect. Three areas extracted from the U.S. Geological Survey's National Elevation Dataset were transformed to the wavelet domain using the third order filters of the Daubechies family (DAUB6), and were made sparse by setting 95 percent of the smallest wavelet coefficients to zero. The resulting raster is compressible to a corresponding degree. The effects of the nulled coefficients on the reconstructed DEM are noted as residuals in elevation, derived slope and aspect, and delineation of drainage basins and streamlines. A simple masking technique also is presented, that maintains the integrity and flatness of water bodies in the reconstructed DEM.

Oimoen, M.J.

2004-01-01

49

Spatial Characterization of Landscapes through Multifractal Analysis of DEM  

PubMed Central

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. PMID:25177728

Aguado, P. L.; Del Monte, J. P.; Moratiel, R.; Tarquis, A. M.

2014-01-01

50

Calibration and validation of SAR interferometry for DEM generation  

NASA Astrophysics Data System (ADS)

A complete interferometric SAR (InSAR) procedure for the generation of digital elevation models (DEMs) is described, stressing the InSAR geometric aspects. A new approach to transform the interferometric phases to terrain heights is presented, which aims at achieving an accurate geocoding of the InSAR-generated DEMs. It is based on a rigorous model that connects image space to object space and on a least squares (LS) calibration of the InSAR geometry with ground control points (GCPs). The procedure may include the fusion of data coming from ascending and descending pairs of SAR images. For this purpose, a simultaneous calibration of the geometry of different InSAR pairs is proposed. It allows reducing the number of required GCPs using tie points, in analogy with the photogrammetric procedures. The validation of two DEMs, one coming from an ascending ERS-1 SAR pair and the other one derived by fusion of ascending and descending ERS-1 data, is described paying attention to the atmospheric effects on the generated DEMs.

Crosetto, M.

51

DIGITAL ELEVATION MODEL (DEM) FILES (30 M) FOR NORTH CAROLINA  

EPA Science Inventory

Digital Elevation Model files, 30-m resolution, for North Carolina from US Geological Survey Web site: http://edcwww.cr.usgs.gov/doc/edchome/ndcdb/7_min_dem/states/NC.html Files listed for NC but centered in TN, GA, and VA are not included. All file archives were downloaded an...

52

Structural analysis using DEM and COLTOP- 3D computer program  

Microsoft Academic Search

The analysis of a Digital Elevation Model (DEM) with the software COLTOP-3D makes it possible to create 3D shaded, coloured relief maps. These maps combine both slope angle maps and slope aspect maps, highlighting the orientation of the topography. The topography can thus be interpreted by means of a stereonet. Further topographic analysis enables to identify structural features. Faults, as

Baillifard François

2004-01-01

53

TSUNAMI INUNDATION MAPPING FOR OCEAN CITY, MD NGDC DEM  

E-print Network

TSUNAMI INUNDATION MAPPING FOR OCEAN CITY, MD NGDC DEM BY BABAK TEHRANIRAD, SAEIDEH BANIHASHEMI BY THE NATIONAL TSUNAMI HAZARD MITIGATION PROGRAM NATIONAL WEATHER SERVICE GRANT NA10NWS4670010 CENTER FOR APPLIED COASTAL RESEARCH Ocean Engineering Laboratory University of Delaware Newark, Delaware 19716 #12;Tsunami

Kirby, James T.

54

DEM integrity monitor experiment (DIME) flight test results  

NASA Astrophysics Data System (ADS)

This paper discusses flight test results of a Digital Elevation Model (DEM) integrity monitor. The DEM Integrity Monitor Experiment (DIME) was part of the NASA Synthetic Vision System (SVS) flight trials at Eagle-Vail, Colorado (EGE) in August/September, 2001. SVS provides pilots with either a Heads-down Display (HDD) or a Heads-up Display (HUD) containing aircraft state, guidance and navigation information, and a virtual depiction of the terrain as viewed 'from the cockpit'. SVS has the potential to improve flight safety by increasing the situational awareness (SA) in low to near zero-visibility conditions to a level of awareness similar to daytime clear-weather flying. This SA improvement not only enables low-visibility operations, but may also reduce the likelihood of Controlled Flight Into Terrain (CFIT). Because of the compelling nature of SVS displays high integrity requirements may be imposed on the various databases used to generate the imagery on the displays even when the target SVS application does not require an essential or flight-critical integrity level. DIME utilized external sensors (WAAS and radar altimeter) to independently generate a 'synthesized' terrain profile. A statistical assessment of the consistency between the synthesized profile and the profile as stored in the DEM provided a fault-detection capability. The paper will discuss the basic DIME principles and will show the DIME performance for a variety of approaches to Runways 7 and 25 at EGE. The monitored DEMs are DTED Level 0, USGS with a 3-arcsec spatial resolution, and a DEM provided by NASA Langley. The test aircraft was a Boeing 757-200.

Uijt de Haag, Maarten; Young, Steve D.; Sayre, Jonathon; Campbell, Jacob; Vadlamani, Ananth

2002-07-01

55

3D Bildgebung von zerebralen Aneurysmen Vergleich zwischen CT und MRT  

NASA Astrophysics Data System (ADS)

Patientenspezifische Strömungs- und die Geometrieanalyse von Aneurysmen basiert auf der 3D-Rekonstruktion aus Daten, die mit modernen Methoden der Bildgebung (z.B. CT und MRT) gewonnen werden. Die unterschiedlichen Charakteristika der Bildgebungsverfahren und die damit verbundenen Unsicherheiten führen zu Variationen der rekonstruierten Geometrien, die sich auf die numerische Berechnung von Strömungsparametern, wie z.B. die Wandschubspannung, auswirken können. Basierend auf CT- und MRT-Aufnahmen eines anatomisch realistischen Referenzmodells eines zerebralen Aneurysmas der Arteria Basilaris vergleichen wir die rekonstruierten Geometrien und die hierin simulierten Blutströmungen. Die Segmentierung und Rekonstruktion des Aneurysmas erfolgte mit Hilfe des Programms AMIRA. Die numerischen Strömungsberechnungen wurden mit dem Strömungslöser FLUENT durchgeführt.

Goubergrits, Leonid; Pöthke, Jens; Petz, Christoph; Hege, Hans-Christian; Spuler, Andreas; Kertzscher, Ulrich

56

Precise integrated topography of Dokdo, East Sea, Korea, using LIDAR DEM and Multibeam echo sounding data  

Microsoft Academic Search

In this study, We created and analyzed Precise integrated topography of Dokdo, East Sea, Korea, using land data that were collected by airborne LIDAR(Light Detection and Ranging) DEM(Digital Elevation Model) and seafloor bathymetry data by Multi-beam echo sounder. Airborne LIDAR DEM represent more detailed topography of land than other DEM data. Composition of airborne LIDAR DEM and aerial photograph produced

C. Kim; H. Joo; E. Jeong; S. Lee; H. Kim

2009-01-01

57

The TanDEM-X Digital Elevation Model and Terrestrial Impact Craters  

NASA Astrophysics Data System (ADS)

The Digital Elevation Model (DEM) derived in the TanDEM-X mission is generated from data of the German X-band TerraSAR-X and TanDEM-X satellites, launched in June 2007 and June 2010, respectively. The complete final TanDEM-X DEM will be available by 2015. It achieves global coverage together with an accuracy in the sub-10 m range and a spatial resolution of 12 m at the equator. Thus it exceeds the quality of current elevation models generated from space-borne remote sensing data, e.g., SRTM X-band (15m/30m with limited coverage) considerably. The TanDEM-X DEM supports studies of terrestrial impact craters by revealing the morphology and topography of simple and complex structures, together with the surrounding terrain, in great detail - even for craters in very remote areas. In a first approach we apply the TanDEM-X digital elevation data to the impact crater record of the exposed entries in the Earth Impact Database (EID) of the Planetary and Space Science Center at the University of New Brunswick, Canada. This allows evaluation of how structures of confirmed origin are reflected in the TanDEM-X DEM data. Our early assessment analyses - using intermediate DEM processing products - suggest that of the about 120 EID entries of the exposed type 80%-90% can be identified in the DEM data. As the final elevation data successively will emerge during processing, we will generate for all known impact structures with visible surface features a homogeneous set of information extracted from the TanDEM-X DEM including, e.g., high precision maps, elevation profiles, etc. This catalogue can be used for further detailed studies or the development of search algorithms for potential impact features in selected areas. This presentation describes the current status of our research and illustrates several TanDEM-X DEM maps of known terrestrial impact craters.

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

58

RESEARCH/REVIEW ARTICLE A new DEM of the Austfonna ice cap by combining differential  

E-print Network

and ice caps. On Austfonna, digital elevation models (DEMs) have been used to delineate glacier drainage of Oslo, PO Box 1047 Blindern, NO-0316 Oslo, Norway Keywords SAR; ICESat; DEM; Austfonna; ice cap; glacier, Norway. E-mail: gmoholdt@ucsd.edu Abstract We present a new digital elevation model (DEM

Kääb, Andreas

59

DEM GENERATION FROM ASTER SATELLITE DATA FOR GEOMORPHOMETRIC ANALYSIS OF CERRO SILLAJHUAY, CHILE/BOLIVIA  

E-print Network

DEM GENERATION FROM ASTER SATELLITE DATA FOR GEOMORPHOMETRIC ANALYSIS OF CERRO SILLAJHUAY, CHILE and Reflection Radiometer) satellite data. The original 30-m DEM was generated by using tie points data with sub-pixel accuracy is possible (Krzystek 1995). DEMs can be generated from stereo satellite

Bolch, Tobias

60

Effect of DEM mesh size on AnnAGNPS simulation and slope correction.  

PubMed

The objective of this paper is to study the impact of the mesh size of the digital elevation model (DEM) on terrain attributes within an Annualized AGricultural NonPoint Source pollution (AnnAGNPS) Model simulation at watershed scale and provide a correction of slope gradient for low resolution DEMs. The effect of different grid sizes of DEMs on terrain attributes was examined by comparing eight DEMs (30, 40, 50, 60, 70, 80, 90, and 100 m). The accuracy of the AnnAGNPS stimulation on runoff, sediments, and nutrient loads is evaluated. The results are as follows: (1) Rnoff does not vary much with decrease of DEM resolution whereas soil erosion and total nitrogen (TN) load change prominently. There is little effect on runoff simulation of AnnAGNPS modeling by the amended slope using an adjusted 50 m DEM. (2) A decrease of sediment yield and TN load is observed with an increase of DEM mesh size from 30 to 60 m; a slight decrease of sediment and TN load with the DEM mesh size bigger than 60 m. There is similar trend for total phosphorus (TP) variation, but with less range of variation, the simulation of sediment, TN, and TP increase, in which sediment increase up to 1.75 times compared to the model using unadjusted 50 m DEM. In all, the amended simulation still has a large difference relative to the results using 30 m DEM. AnnAGNPS is less reliable for sediment loading prediction in a small hilly watershed. (3) Resolution of DEM has significant impact on slope gradient. The average, minimum, maximum of slope from the various DEMs reduced obviously with the decrease of DEM precision. For the grade of 0?15°, the slopes at lower resolution DEM are generally bigger than those at higher resolution DEM. But for the grade bigger than 15°, the slopes at lower resolution DEM are generally smaller than those at higher resolution DEM. So it is necessary to adjust the slope with a fitting equation. A cubic model is used for correction of slope gradient from lower resolution to that from higher resolution. Results for Dage watershed showed that fine meshes are desired to avoid large underestimates of sediment and total nitrogen loads and moderate underestimates of total phosphorus loads even with the slopes for the 50 m DEM adjusted to be more similar to the slopes from the 30 m DEM. Decreasing the mesh size beyond this threshold does not substantially affect the computed runoff flux but generated prediction errors for nitrogen and sediment yields. So the appropriate DEM will control error and make simulation at acceptable level. PMID:20953988

Wang, Xiaoyan; Lin, Q

2011-08-01

61

The Shuttle Radar Topography Mission: A Global DEM  

NASA Technical Reports Server (NTRS)

Digital topographic data are critical for a variety of civilian, commercial, and military applications. Scientists use Digital Elevation Models (DEM) to map drainage patterns and ecosystems, and to monitor land surface changes over time. The mountain-building effects of tectonics and the climatic effects of erosion can also be modeled with DEW The data's military applications include mission planning and rehearsal, modeling and simulation. Commercial applications include determining locations for cellular phone towers, enhanced ground proximity warning systems for aircraft, and improved maps for backpackers. The Shuttle Radar Topography Mission (SRTM) (Fig. 1), is a cooperative project between NASA and the National Imagery and Mapping Agency (NIMA) of the U.S. Department of Defense. The mission is designed to use a single-pass radar interferometer to produce a digital elevation model of the Earth's land surface between about 60 degrees north and south latitude. The DEM will have 30 m pixel spacing and about 15 m vertical errors.

Farr, Tom G.; Kobrick, Mike

2000-01-01

62

BOREAS Regional DEM in Raster Format and AEAC Projection  

NASA Technical Reports Server (NTRS)

This data set is based on the GTOPO30 Digital Elevation Model (DEM) produced by the United States Geological Survey EROS Data Center (USGS EDC). The BOReal Ecosystem-Atmosphere Study (BOREAS) region (1,000 km x 1000 km) was extracted from the GTOPO30 data and reprojected by BOREAS staff into the Albers Equal-Area Conic (AEAC) projection. The pixel size of these data is 1 km. The data are stored in binary, image format files.

Knapp, David; Verdin, Kristine; Hall, Forrest G. (Editor)

2000-01-01

63

High-precision DEM reconstruction based on airborne LiDAR point clouds  

NASA Astrophysics Data System (ADS)

Airborne LiDAR point clouds have become important data sources for DEM generation recently; however the problem of low precision and low efficiency in DEM production still exists. This paper proposes a new technical scheme for high-precision DEM production based on airborne LiDAR point clouds systematically. Firstly, an elevation and density analysis method is applied to filter out outliers. Secondly, ground points are detected by an improved filter algorithm based on the hierarchical smoothing method. Finally, feature lines are extracted by the planar surface fitting and intersecting method, and a simple data structure of feature lines preserved DEM is proposed to achieve reconstructing high accuracy DEM, combing feature lines with ground points. Experimental results show that the proposed scheme is able to compensate for deficiencies of existing DEM reconstruction techniques and can meet the needs of high precision DEM production based on LiDAR data.

Xu, Jingzhong; Kou, Yuan; Wang, Jun

2014-05-01

64

3D DEM analyses of the 1963 Vajont rock slide  

NASA Astrophysics Data System (ADS)

The 1963 Vajont rock slide has been modelled using the distinct element method (DEM). The open-source DEM code, YADE (Kozicki & Donzé, 2008), was used together with the contact detection algorithm proposed by Boon et al. (2012). The critical sliding friction angle at the slide surface was sought using a strength reduction approach. A shear-softening contact model was used to model the shear resistance of the clayey layer at the slide surface. The results suggest that the critical sliding friction angle can be conservative if stability analyses are calculated based on the peak friction angles. The water table was assumed to be horizontal and the pore pressure at the clay layer was assumed to be hydrostatic. The influence of reservoir filling was marginal, increasing the sliding friction angle by only 1.6?. The results of the DEM calculations were found to be sensitive to the orientations of the bedding planes and cross-joints. Finally, the failure mechanism was investigated and arching was found to be present at the bend of the chair-shaped slope. References Boon C.W., Houlsby G.T., Utili S. (2012). A new algorithm for contact detection between convex polygonal and polyhedral particles in the discrete element method. Computers and Geotechnics, vol 44, 73-82, doi.org/10.1016/j.compgeo.2012.03.012. Kozicki, J., & Donzé, F. V. (2008). A new open-source software developed for numerical simulations using discrete modeling methods. Computer Methods in Applied Mechanics and Engineering, 197(49-50), 4429-4443.

Weng Boon, Chia; Houlsby, Guy; Utili, Stefano

2013-04-01

65

A global database of volcano edifice morphometry using SRTM DEMs  

NASA Astrophysics Data System (ADS)

The morphometry of volcanic edifices reflects the aggradational and degradational processes that interact during their evolution. In association with VOGRIPA, a global risk identification project, we are currently constructing a database on the morphometry of volcanic edifices using digital elevation models (DEMs) from the Shuttle Radar Topography Mission (SRTM). Our aim is to compile and make available a global database of morphometric parameters that characterize the shape and size of volcanic edifices. The 90-meter SRTM DEM is presently the best public-access DEM dataset for this task because of its near-global coverage and spatial resolution that is high enough for the analysis of composite volcanic edifices. The Smithsonian Institution database lists 1536 active/potentially active volcanoes worldwide. Of these, ~900 volcano edifices can be analyzed with the SRTM DEMs, discarding volcanoes not covered by the dataset above latitudes 60°N and 56°S, submarine volcanoes, volcanoes with mostly negative topographies (i.e. calderas, maars) and monogenetic cones and domes, which are too small to accurately study with the 90-meter resolution. Morphometric parameters are acquired using an expressly written IDL-language code named MORVOLC. Edifice outline is determined via a semi-automated algorithm that identifies slope-breaks between user-estimated maximum and minimum outlines. Thus, volcanic edifices as topographic entities are considered, excluding aprons or ring plains and other far-reaching volcanic products. Several morphometric parameters are computed which characterize edifice size and shape. Size parameters are height (from base to summit), volume, base and summit areas and widths (average, minimum, maximum). Plan shape is summarized using two independent dimensionless indexes that describe the shape of the elevation contours, ellipticity (quantifies the elongation of each contour) and irregularity (quantifies the irregularity or complexity of each contour). Profile shape is summarized using dimensionless ratios (height/basal width, summit width/basal width) and slope statistics (mean, maximum interval, slope variation vs. height). A degree of radial symmetry is also calculated, as well as the azimuth of edifice elongation, the strike and dip of the basal surface and the number of summit and flank peaks. In addition to the morphometric parameters, graphs, profiles and maps are also generated. We anticipate that the database will be useful for regional comparisons, for quantitative and systematic classifications, and as a tool for studies of associated volcanological processes (e.g. Grosse et al., 2009, Geology).

Grosse, P.; van Wyk de Vries, B.; Petrinovic, I. A.; Euillades, P. A.

2009-12-01

66

In need of combined topography and bathymetry DEM  

NASA Astrophysics Data System (ADS)

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. Although the coverage of this database is only a small portion of the Earth, the database has been highly appreciated in the academic community, and accepted in surprise by the general public when the database was displayed in 3D imagery to show its quality. This database could be rather smoothly combined with the finer land DEM of 250m spatial resolution (Japan250m.grd, K. Kisimoto, 2000). One of the most important applications of this combined DEM of topography and bathymetry is tsunami modeling. Understanding of the coastal environment, management and development of the coastal region are other fields in need of these data. There is, however, an important issue to consider when we create a combined DEM of topography and bathymetry in finer resolutions. The problem arises from the discrepancy of the standard datum planes or reference levels used for topographic leveling and bathymetric sounding. Land topography (altitude) is defined by leveling from the single reference point determined by average mean sea level, in other words, land height is measured from the geoid. On the other hand, depth charts are made based on depth measured from locally determined reference sea surface level, and this value of sea surface level is taken from the long term average of the lowest tidal height. So, to create a combined DEM of topography and bathymetry in very fine scale, we need to avoid this inconsistency between height and depth across the coastal region. Height and depth should be physically continuous relative to a single reference datum across the coast within such new high resolution DEMs. (N.B. Coast line is not equal to 'altitude-zero line' nor 'depth-zero line'. It is defined locally as the long term average of the highest tide level.) All of this said, we still need a lot of work on the ocean side. Global coverage with detailed bathymetric mapping is still poor. Seafloor imaging and other geophysical measurements/experiments should be organized and conducted internationally and interdisciplinary ways more than ever. We always need greater technological advancement

Kisimoto, K.; Hilde, T.

2003-04-01

67

Solar DEM Models : A solar image in color band b, mn pixels,  

E-print Network

Solar DEM Models : A solar image in color band b, mÃ?n pixels, containing a particular solar feature, for t = 1, 2, . . . , T. btM sianFieldRandomGaus I M I I bbb T t bbtt bbb bb 2 1 2 )( #12;Solar DEM.bI : the measure error of the ith row and jth column pixel of the certain image in color band b. ijbe #12;Solar DEM

Wolfe, Patrick J.

68

Identifying LiDAR sample uncertainty on terrain features from DEM simulation  

NASA Astrophysics Data System (ADS)

Light detection and ranging (LiDAR) is an effective technology to detect highly dense-point elevation data from terrain surfaces. The density of LiDAR data points significantly affects the level of detail of a high-resolution digital elevation model (DEM). In this study, the conditioned Latin hypercube sampling (cLHS) and simple random sampling (SRS) methods select sufficient LiDAR samples, and sequential Gaussian simulation (SGS) generates multiple DEM realizations that are a set of simulated DEM maps subject to a specified mean, variance, and spatial structure of measured data. Based on DEM realizations, the uncertainty of a spatial feature with a specified elevation is determined.

Chu, Hone-Jay; Chen, Ruey-An; Tseng, Yi-Hsing; Wang, Cheng-Kai

2014-01-01

69

DEM, tide and velocity over sulzberger ice shelf, West Antarctica  

USGS Publications Warehouse

Arctic and Antarctic ice sheets preserve more than 77% of the global fresh water and could raise global sea level by several meters if completely melted. Ocean tides near and under ice shelves shifts the grounding line position significantly and are one of current limitations to study glacier dynamics and mass balance. The Sulzberger ice shelf is an area of ice mass flux change in West Antarctica and has not yet been well studied. In this study, we use repeat-pass synthetic aperture radar (SAR) interferometry data from the ERS-1 and ERS-2 tandem missions for generation of a high-resolution (60-m) Digital Elevation Model (DEM) including tidal deformation detection and ice stream velocity of the Sulzberger Ice Shelf. Other satellite data such as laser altimeter measurements with fine foot-prints (70-m) from NASA's ICESat are used for validation and analyses. The resulting DEM has an accuracy of-0.57??5.88 m and is demonstrated to be useful for grounding line detection and ice mass balance studies. The deformation observed by InSAR is found to be primarily due to ocean tides and atmospheric pressure. The 2-D ice stream velocities computed agree qualitatively with previous methods on part of the Ice Shelf from passive microwave remote-sensing data (i.e., LANDSAT). ?? 2005 IEEE.

Baek, S.; Shum, C.K.; Lee, H.; Yi, Y.; Kwoun, O.-I.; Lu, Z.; Braun, A.

2005-01-01

70

Extraction of Hydrological Proximity Measures from DEMs using Parallel Processing  

SciTech Connect

Land surface topography is one of the most important terrain properties which impact hydrological, geomorphological, and ecological processes active on a landscape. In our previous efforts to develop a soil depth model based upon topographic and land cover variables, we extracted a set of hydrological proximity measures (HPMs) from a Digital Elevation Model (DEM) as potential explanatory variables for soil depth. These HPMs may also have other, more general modeling applicability in hydrology, geomorphology and ecology, and so are described here from a general perspective. The HPMs we derived are variations of the distance up to ridge points (cells with no incoming flow) and variations of the distance down to stream points (cells with a contributing area greater than a threshold), following the flow path. These HPMs were computed using the D-infinity flow model that apportions flow between adjacent neighbors based on the direction of steepest downward slope on the eight triangular facets constructed in a 3 x 3 grid cell window using the center cell and each pair of adjacent neighboring grid cells in turn. The D-infinity model typically results in multiple flow paths between 2 points on the topography, with the result that distances may be computed as the minimum, maximum or average of the individual flow paths. In addition, each of the HPMs, are calculated vertically, horizontally, and along the land surface. Previously, these HPMs were calculated using recursive serial algorithms which suffered from stack overflow problems when used to process large datasets, limiting the size of DEMs that could be analyzed using that method to approximately 7000 x 7000 cells. To overcome this limitation, we developed a message passing interface (MPI) parallel approach for calculating these HPMs. The parallel algorithms of the HPMs spatially partition the input grid into stripes which are each assigned to separate processes for computation. Each of those processes then uses a queue data structure to order the processing of cells so that each cell is visited only once and the cross-process communications that are a standard part of MPI are handled in an efficient manner. This parallel approach allows analysis of much larger DEMs as compared to the serial recursive algorithms. In this paper, we present the definitions of the HPMs, the serial and parallel algorithms used in their extraction and their potential applications in hydrology, geomorphology and ecology.

Tesfa, Teklu K.; Tarboton, David G.; Watson, Daniel W.; Schreuders, Kimberly A.; Baker, Matthew M.; Wallace, Robert M.

2011-12-01

71

The Discrepancy Evaluation Model. II. The Application of the DEM to an Educational Program.  

ERIC Educational Resources Information Center

The discrepancy evaluation model (DEM) specifies that evaluation consists of comparing performance with a standard, yielding discrepancy information. DEM is applied to programs in order to improve the program by making standards-performance-discrepancy cycles explicit and public. Action-oriented planning is involved in creating standards; a useful…

Steinmetz, Andres

1976-01-01

72

C-DEM: A Multi-Modal Query System for Drosophila Embryo Databases  

E-print Network

C-DEM: A Multi-Modal Query System for Drosophila Embryo Databases Fan Guo, Lei Li, Christos hindgut"). C-DEM is an online system for Drosophila (= fruit-fly) Embryo images Mining. It supports images (and keywords, and genes). The demo is on a real Drosophila Embryo database, with 10,204 images, 2

73

Solar DEM Model Proposal : A solar image in color band b, mn pixels,  

E-print Network

Solar DEM Model Proposal : A solar image in color band b, m�n pixels, containing a particular solar 11 )( #12;Solar DEM Model Proposal : the volume (abundance?) of ion ii : the proportion of the total volume at temperature t t T t bitt I i ib MIE 11 )( #12;Solar Dataset · 15 Filters.txt files

Wolfe, Patrick J.

74

USING ERS SAR INTERFEROMETRY FOR DEM CREATION IN THE CZECH REPUBLIC  

Microsoft Academic Search

This paper summarises first results of the study carrying out in the frame of the programme for co-operation between European Space Agency and Czech Republic. One part of the study concentrates on the evaluation and development of the application potential of the SAR interferometry technique for DEM generation in the Czech Republic. The only DEM currently available for the entire

Lubos Kucera

75

DEM investigations of fluidized beds in the presence of liquid coating  

Microsoft Academic Search

In this work, the impact of liquid coating on fluidized bed behavior is studied by performing DEM investigations. A wet coefficient of restitution model, accounting for the viscous and capillary forces in addition to the inelasticity of particles, is implemented in an open-source numerical tool — MFIX-DEM. The modified numerical tool is used to study the effect of the coating

Pirooz Darabi; Konstantin Pougatch; Martha Salcudean; Dana Grecov

2011-01-01

76

Assoziativspeicher und eine erste Skizze von Konrad Zuse aus dem Jahre 1943  

NASA Astrophysics Data System (ADS)

In dem Beitrag wird eine Handskizze von Konrad Zuse aus dem Jahre 1943 eines assoziativen Speichers in Relaistechnik diskutiert. Die Diskussion ist eingebettet in die Grundlagen des assoziativen Speicherproblems. Zum Schluss des Beitrages werden einige Vorschläge zu MOSRealisierung der Zuse-Schaltung unterbreitet.

Waldschmidt, Klaus

77

North York (Yonge Street) building outlines with heights, clutter data, DEM, contours and places  

E-print Network

Title: North York (Yonge Street) building outlines with heights, clutter data, DEM, contours core - Clutter data (Landuse Data includes: 1 Inland Water 2 Open 3 Low tree density 4 High Tree with heights, clutter data, DEM, contours and places]" [electronic resource: raster and vector]. Newark

78

Downtown Toronto building outlines with heights, clutter data, DEM, contours and places  

E-print Network

Title: Downtown Toronto building outlines with heights, clutter data, DEM, contours and places Data - Clutter data (Landuse Data includes: 1 Inland Water 2 Open 3 Low tree density 4 High Tree density 5 (gislib@yorku.ca) Citation: RMSI. "[Downtown Toronto building outlines with heights, clutter data, DEM

79

Building reconstruction from a single DEM Florent Lafarge1,2  

E-print Network

Building reconstruction from a single DEM Florent Lafarge1,2 , Xavier Descombes1 , Josiane Zerubia1 approach for building reconstruction from a single Digital Elevation Model (DEM). It treats buildings such as urban planning, radiowave reachability tests for wireless communications, disaster re- covery

Paris-Sud XI, Université de

80

DEM ball bearing model and defect diagnosis by electrical measurement  

NASA Astrophysics Data System (ADS)

We propose in this paper a new method for the monitoring and diagnosis of bearing defects which utilises the sensitivity and the richness of the local electrical signature of the ball bearings. Experimental results show the capability of the electrical measurement to betray the existence of defect. A new model of ball bearing is presented based on Discrete Element Method (DEM), in which the mechanical behavior of ball bearing is reproduced correctly. Numerical simulations are carried out to highlight the influence of angular velocity on the electrical signal of healthy ball bearing. Moreover, the numerical simulations are performed in the case of defected ball bearing. The electrical signals obtained are in good agreement with theoretical frequencies. The numerical study underscore the capability of electrical response to detect geometrical defects.

Bourbatache, K.; Guessasma, M.; Bellenger, E.; Bourny, V.; Fortin, J.

2013-12-01

81

Mixing equilibrium in two-density fluidized beds by DEM  

NASA Astrophysics Data System (ADS)

Interaction of fluid and granular flows in dense two-phase systems is responsible for the significantly different behavior of units used in the chemical industry such as fluidized beds. The momentum exchange phenomena involved during gas fluidization of a binary mixture of solids differing in density is such that the continuous mixing action of the fluid flowing upwards counteracts the natural tendency of the two (fluidized) solids to segregate with the heavier component fully settling at the bottom of the bed. In the present work the complex hydrodynamics of two-density gas-fluidized beds is studied by means of a DEM-CFD computational approach, combining the discrete element method (DEM) and a solution of the locally averaged equations of motion (CFD). The model is first validated against experimental data and then used to investigate the role of gas velocity versus density ratio of the two components in determining the distribution of the components in the system. It is shown first that a unique equilibrium composition profile is reached independent of the initial arrangements of the solids. Then, numerical simulations are used to find the equilibrium conditions of mixing/segregation as a function of the gas velocity in excess of the minimum fluidization velocity of the heavier component and as a function of the density ratio of the two solid species. A mixing map on the gas velocity-density ratio plane is finally reconstructed by plotting iso-mixing lines that shows quantitatively how conditions ranging from full mixing to fully segregated components are obtained.

Di Renzo, A.; Di Maio, F. P.

2010-05-01

82

Two Preliminary SRTM DEMs Within the Amazon Basin  

NASA Astrophysics Data System (ADS)

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.

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

2002-12-01

83

APPENDIX II II.1 Goodwin Creek DEM, Land Use, Soil Type, and Watershed Definition at Different Spatial  

E-print Network

APPENDIX II II.1 Goodwin Creek DEM, Land Use, Soil Type, and Watershed Definition at Different-------------------------------------------------------------------------------------------------------II-2 Figure II.1.1 DEM, watershed definition, soil type, and land use at 30-m ------------------II-2 Figure II.1.2 DEM, watershed definition, soil type, and land use at 90-m ------------------II-3 Figure II

Julien, Pierre Y.

84

DESCRIPTION OF A DEDICATED HARDWARE ARCHITECTURE FOR THE DISCRETE ELEMENT METHOD (DEM) IMPLEMENTED ON A FIELD PROGRAMMABLE GATE ARRAY (FPGA)  

Microsoft Academic Search

1 Abstract The Discrete Element Method (DEM) is a numerical method for the simulation of the behaviour of media consisting of discrete particles. The DEM is very computationally expensive, but has properties that make it very attractive for acceleration by novel computational methods. The DEM is becoming even more popular as it is suggested that particle based methods will replace,

B. Carrión Schäfer; S. F. Quigley; A. H. C. Chan

85

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

NASA Astrophysics Data System (ADS)

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.

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

2013-06-01

86

Stress analysis during slope failure from DEM simulations  

NASA Astrophysics Data System (ADS)

We used Discrete Element Method (DEM) simulations to study the initiation and evolution of landsliding, with a focus on the development and propagation of the sliding plane, and on the effects of material strength on the behavior of the slope material during landsliding. Our simulated slopes were constructed of homogeneous materials, settled under gravity, bonded, and excavated to produce 70 deg slopes of 1050 m in height. Nine simulations were carried out, each using a different value of cohesions, ranging from 0.7 to 4.2 MPa (quantified through DEM direct shear simulations on representative materials). In each of our simulations, failure initiated at the foot of the slope, accompanied by disintegration of the slope material. Failure then propagated upward to the slope crest with further material disintegration. A discrete detachment surface formed below the disintegrated material. Downslope movement of the failed material (i.e. landsliding) occurred only after the failure plane intersected the upper slope face. By the end of landsliding, the disintegrated slope material formed a talus like deposit at the foot of the slope. The value of initial material cohesion influenced the nature of the landslide deposit and its dimension. Higher material strengths produced smaller landslides, as well as the occurrence of discrete landslide blocks, which originated from the shallow slopes, and became entrained within the finer talus. Stress analysis of the slope failure process clarifies how failure initiates and landsliding evolves, and further constrains the limiting failure criteria that define each simulated material. The local proximity to failure throughout the slope can be tracked during the simulation, revealing that high failure potential (high shear stress relative to mean stress) exists at the toe of the slope immediately following excavation. As material disintegrates near the toe of the slope, high tensile stresses develop in the overlying mass, causing the break-up of the shallower slope materials. The detachment surface defines the boundary between the mobile material undergoing disintegration and the coherent material below. With increased cohesion within the slope, less material reaches this failure condition, and the detachment surface shallows, causing a decrease in the in-slope extent of the landslide, the volume of the final deposit and type of failure (slump vs. rock-slide). These numerical simulations provide important insights into the stress evolution within a failing slope, and an understanding of how these control the final type, geometry and size of landlides.

Katz, O.; Morgan, J. K.

2012-04-01

87

tDCS am DLPFC zur Raucherentwöhnung.  

E-print Network

??Hintergrund: Verschiedene bildgebende Studien haben einen Zusammenhang von dem Craving/Verlangen nach Nikotin und der Regulation von Emotionen in der Aktivität des linken und rechten dorsolateralen… (more)

Köhler, Ulla

2012-01-01

88

The influence of slope profile extraction techniques and DEM resolution on 2D rockfall simulation  

NASA Astrophysics Data System (ADS)

The development of advanced 3D rockfall modelling algorithms and tools during the last decade has allowed to gain insights in the topographic controls on the quality and reliability of rockfall simulation results. These controls include DEM resolution and roughness, and depend on the adopted rockfall simulation approach and DEM generation techniques. Despite the development of 3D simulations, the 2D modelling approach still remains suitable and convenient in some cases. Therefore, the accuracy of high-quality 3D descriptions of topography must be preserved when extracting slope profiles for 2D simulations. In this perspective, this study compares and evaluates three different techniques commonly used to extract slope profiles from DEM, in order to assess their suitability and effects on rockfall simulation results. These methods include: (A) an "interpolated shape" method (ESRI 3D Analyst), (B) a raw raster sampling method (EZ Profiler), and (C) a vector TIN sampling method (ESRI 3D Analyst). The raster DEMs used in the study were all derived from the same TIN DEM used for method C. For raster DEM, the "interpolated shape" method (A) extracts the profile by bi-linear interpolating the elevation among the four neighbouring cells at each sampling location along the profile trace. The EZ Profiler extension (B) extracts the profile by sampling elevation values directly from the DEM raster grid at each sampling location. These methods have been compared to the extraction of profiles from TIN DEM (C), where slope profile elevations are directly obtained by sampling the TIN triangular facets. 2D rockfall simulations performed using a widely used commercial software (RocfallTM) with the different profiles show that: (1) method A and C provide similar results; (2) runout simulated using profiles obtained by method A is usually shorter than method C; (3) method B presents abrupt horizontal steps in the profiles, resulting in unrealistic runout. To study the influence of DEM resolution on rockfall simulation, profiles have been extracted from 1m, 5m, 10m and 15m gridded DEMs. The 2D rockfall simulations with the different resolution show that: (1) the effect of different resolution depends on topographic characteristics of the slope (e.g., steep or flat); (2) for steep slopes the rockfall motion is dominated by bouncing, and the coarser DEMs result in lower bouncing and lower kinematic energies and velocities; (3) for flat slopes, the motion is dominated by rolling and sliding, and the effect is the opposite: the coarser the DEM, the longer the runout.

Wang, X.; Frattini, P.; Agliardi, F.; Crosta, G. B.

2012-04-01

89

SPH-DEM simulations of grain dispersion by liquid injection  

NASA Astrophysics Data System (ADS)

We study the dispersion of an initially packed, static granular bed by the injection of a liquid jet. This is a relevant system for many industrial applications, including paint dispersion or food powder dissolution. Both decompaction and dispersion of the powder are not fully understood, leading to inefficiencies in these processes. Here we consider a model problem where the liquid jet is injected below a granular bed contained in a cylindrical cell. Two different initial conditions are considered: a two-phase case where the bed is initially fully immersed in the liquid and a three-phase case where the bed and cell are completely dry preceding the injection of the liquid. The focus of this contribution is the simulation of these model problems using a two-way coupled SPH-DEM granularliquid method [M. Robinson, M. Ramaioli, and S. Luding, submitted (2013) and http://arxiv.org/abs/1301.0752 (2013)]. This is a purely particle-based method without any prescribed mesh, well suited for this and other problems involving a free (liquidgas) surface and a partly immersed particle phase. Our simulations show the effect of process parameters such as injection flow rate and injection diameter on the dispersion pattern, namely whether the granular bed is impregnated bottom-up or a jet is formed and compare well with experiments.

Robinson, Martin; Luding, Stefan; Ramaioli, Marco

2013-06-01

90

A Study of the Novel of Otto Ludwig based on “Maria,” “Die Heiterethei u. i Widerspiel” and “Zwischen Himmel u. Erde”  

E-print Network

e s s l y waits f o r an answer,"Ein #1.Zwischen Himmel u. Erde p. #2.Bleak House Chap.X. #3.Zwischen Himmel u. Erde.p.347 #5.Dombey and Son.Chap.LIII. - 13 - halb Vaterunser lang hörte man nichts als das Ticken der Uhr und das wurde immer... matt vornüber, als wollte sie um die Ecke nach H i l f e sehen. Da keine kam X X X X da sank i h r , ein B i l d s t i l l e r Ergebung,das Haupt auf die Kniee; dann brachen auoh diese ein, und der Tod löste zu früh,wenn au^ mit sanfter Hand , einen...

Palmer, Emma Mae

1909-01-01

91

What is the effect of LiDAR-derived DEM resolution on large-scale watershed model results?  

SciTech Connect

This paper examines the effect of raster cell size on hydrographic feature extraction and hydrological modeling using LiDAR derived DEMs. LiDAR datasets for three experimental watersheds were converted to DEMs at various cell sizes. Watershed boundaries and stream networks were delineated from each DEM and were compared to reference data. Hydrological simulations were conducted and the outputs were compared. Smaller cell size DEMs consistently resulted in less difference between DEM-delineated features and reference data. However, minor differences been found between streamflow simulations resulted for a lumped watershed model run at daily simulations aggregated at an annual average. These findings indicate that while higher resolution DEM grids may result in more accurate representation of terrain characteristics, such variations do not necessarily improve watershed scale simulation modeling. Hence the additional expense of generating high resolution DEM's for the purpose of watershed modeling at daily or longer time steps may not be warranted.

Ping Yang; Daniel B. Ames; Andre Fonseca; Danny Anderson; Rupesh Shrestha; Nancy F. Glenn; Yang Cao

2014-08-01

92

TecDEM: A MATLAB based toolbox for tectonic geomorphology, Part 1: Drainage network preprocessing and stream profile analysis  

NASA Astrophysics Data System (ADS)

We present TecDEM, a software shell implemented in MATLAB that applies tectonic geomorphologic tasks to digital elevation models (DEMs). The first part of this paper series describes drainage partitioning schemes and stream profile analysis. The graphical user interface of TecDEM provides several options: determining flow directions, stream vectorization, watershed delineation, Strahler order labeling, stream profile generation, knickpoints selection, Concavity, Steepness and Hack indices calculations. The knickpoints along selected streams as well as stream profile analysis, and Hack index per stream profile are computed using a semi-automatic method. TecDEM was used to extract and investigate the stream profiles in the Kaghan Valley (Northern Pakistan). Our interpretations of the TecDEM results correlate well with previous tectonic evolution models for this region. TecDEM is designed to assist geoscientists in applying complex tectonic geomorphology tasks to global DEM data.

Shahzad, Faisal; Gloaguen, Richard

2011-02-01

93

Automated sinkhole detection using a DEM subsetting technique and fill tools at Mammoth Cave National Park  

NASA Astrophysics Data System (ADS)

An automated workflow for sinkhole detection is developed using Light Detection and Ranging (Lidar) data from Mammoth Cave National Park (MACA). While the park is known to sit within a karst formation, the generally dense canopy cover and the size of the park (~53,000 acres) creates issues for sinkhole inventorying. Lidar provides a useful remote sensing technology for peering beneath the canopy in hard to reach areas of the park. In order to detect sinkholes, a subsetting technique is used to interpolate a Digital Elevation Model (DEM) thereby reducing edge effects. For each subset, standard GIS fill tools are used to fill depressions within the DEM. The initial DEM is then subtracted from the filled DEM resulting in detected depressions or sinkholes. Resulting depressions are then described in terms of size and geospatial trend.

Wall, J.; Bohnenstiehl, D. R.; Levine, N. S.

2013-12-01

94

Mit dem Umsturz vom 7. November setzte die Revolution in Bayern bereits zwei Tage  

E-print Network

P10108 Mit dem Umsturz vom 7. November setzte die Revolution in Bayern bereits zwei Tage vor Berlin: Hausdruckerei Veranstaltungsreihe 100 Jahre Erster Weltkrieg Revolution und Räterepublik in Bayern 1918/ 19 Von

Schubart, Christoph

95

Uncertainty of SWAT model at different DEM resolutions in a large mountainous watershed.  

PubMed

The objective of this study was to enhance understanding of the sensitivity of the SWAT model to the resolutions of Digital Elevation Models (DEMs) based on the analysis of multiple evaluation indicators. The Xiangxi River, a large tributary of Three Gorges Reservoir in China, was selected as the study area. A range of 17 DEM spatial resolutions, from 30 to 1000 m, was examined, and the annual and monthly model outputs based on each resolution were compared. The following results were obtained: (i) sediment yield was greatly affected by DEM resolution; (ii) the prediction of dissolved oxygen load was significantly affected by DEM resolutions coarser than 500 m; (iii) Total Nitrogen (TN) load was not greatly affected by the DEM resolution; (iv) Nitrate Nitrogen (NO?-N) and Total Phosphorus (TP) loads were slightly affected by the DEM resolution; and (v) flow and Ammonia Nitrogen (NH?-N) load were essentially unaffected by the DEM resolution. The flow and dissolved oxygen load decreased more significantly in the dry season than in the wet and normal seasons. Excluding flow and dissolved oxygen, the uncertainties of the other Hydrology/Non-point Source (H/NPS) pollution indicators were greater in the wet season than in the dry and normal seasons. Considering the temporal distribution uncertainties, the optimal DEM resolutions for flow was 30-200 m, for sediment and TP was 30-100 m, for dissolved oxygen and NO?-N was 30-300 m, for NH?-N was 30 to 70 m and for TN was 30-150 m. PMID:24509347

Zhang, Peipei; Liu, Ruimin; Bao, Yimeng; Wang, Jiawei; Yu, Wenwen; Shen, Zhenyao

2014-04-15

96

The joint TerraSAR-X \\/ TanDEM-X ground segment  

Microsoft Academic Search

This paper recalls the essential elements of the joint TerraSAR-X and TanDEM-X ground segment. It elaborates on some topics which are usually not in the primary focus from a pure SAR technical point of view, e.g. the flight formation. Both commissioning and early routine phase results from operating the joint TerraSAR-X and TanDEM-X ground segment are given.

B. Schattler; R. Kahle; R. Metzig; U. Steinbrecher; M. Zink

2011-01-01

97

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

NASA Astrophysics Data System (ADS)

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 derived by TanDEM-X interferometry taken before and after the eruption. Our results reveal that the eruption had led to a topographic change of up to 200 m in the summit area of Merapi. We further show the ability of the TanDEM-X data to observe much smaller topographic changes using Volcán de Colima as second test site. An explosion at the crater rim signaled the end of magma ascent in June 2011. The bistatic TanDEM-X data give important information on this explosion as we can observe topographic changes of up to 20 m and less in the summit area when comparing datasets taken before and after the event. We further analyzed datasets from the beginning of the year 2013 when Colima got active again after a dormant period. Our results indicate that repeated DEMs with great detail and good accuracy are obtainable, enabling a quantitative estimation of volume changes in the summit area of the volcano. As the TanDEM-X mission is an innovative mission, the present study serves as a test to employ data of a new satellite mission in volcano research. An error analysis of the DEMs to evaluate the volume quantifications was therefore also conducted.

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

2013-12-01

98

Effects of BSO and DEM on thiol-level and radiosensitivity in HeLa cells  

SciTech Connect

Reduction of the intracellular GSH and NPSH levels in HeLa cells by BSO and DEM treatments was determined. As parameters for radiation damage, single and double strand DNA breaks (ssb and dsb) and cell killing were used. Furthermore, repair of ssb and dsb were followed in the first 30 and 120 min after radiation, respectively. BSO and DEM treatment gave a small sensitization for the 3 types of radiation damage (ssb, dsb and cell killing) in aerobic condition. In hypoxic condition the sensitizing effect of both compounds on dsb was larger than the effect on ssb. Pretreatment with BSO and DEM had no influence on repair of ssb and dsb when cells were irradiated in air, but when cells were irradiated in hypoxia, repair was somewhat inhibited after pretreatment with DEM. It can be postulated that a reduction of the intracellular GSH level by BSO and DEM treatment affects cellular radiosensitivity both by a competitive mechanism between GSH and O/sub 2/ and by inhibition of enzymatic repair of DNA breaks, the latter only in the case of DEM treatment.

Vos, O.; Van Der Schans, G.P.; Roos-Verhey, W.S.D.

1984-08-01

99

HELI-DEM portal for geo-processing services  

NASA Astrophysics Data System (ADS)

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) both on the server side (services) and on the client side (interface). In addition to self developed code the system relies mainly on teh software GRASS 7 [1], ZOO-project [2], Geoserver [3] and OpenLayers [4] and the standards WMS [5], WCS [6] and WPS [7]. At the time of writing, the portal offers features like profiling, contour extraction, watershed delineation and analysis, derivatives calculation, data extraction, coordinate conversion but it is evolving and it is planned to extend to a series of environmental modeling that the IST developed in the past like dam break simulation, landslide run-out estimation and floods due to landslide impact in artificial basins. [1] Neteler M., Mitasova H., Open Source GIS: A GRASS GIS Approach. 3rd Ed. 406 pp, Springer, New York, 2008. [2] Fenoy G., Bozon N., Raghavan V., ZOO Project: The Open Wps Platform. Proceeding of 1st International Workshop on Pervasive Web Mapping, Geoprocessing and Services (WebMGS). Como, http://www.isprs.org/proceedings/XXXVIII/4-W13/ID_32.pdf, 26-27 agosto 2010. [3] Giannecchini S., Aime A., GeoServer, il server open source per la gestione interoperabile dei dati geospaziali. Atti 15a Conferenza Nazionale ASITA. Reggia di Colorno, 15-18 novembre 2011. [4] Perez A.S., OpenLayers Cookbook. Packt Publishing, 2012. ISBN 1849517843. [5] OGC, OpenGIS Web Map Server Implementation Specification, http://www.opengeospatial.org/standards/wms, 2006. [6] OGC, OGC WCS 2.0 Interface Standard - Core, http://portal.opengeospatial.org/files/?artifact_id=41437, 2010b. [7] OGC, OpenGIS Web Processing Service, http://portal.opengeospatial.org/files/?artifact_id=24151, 2007.

Cannata, Massimiliano; Antonovic, Milan; Molinari, Monia

2014-05-01

100

ASTER Global DEM contribution to GEOSS demonstrates open data sharing  

NASA Astrophysics Data System (ADS)

The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) remote sensing instrument on the Terra spacecraft has been acquiring images of Earth since launch in 1999. Throughout this time data products have been openly available to the general public through sites in the U.S. and Japan. As the ASTER mission matured, a spatially broad and temporally deep data archive was gradually established. With this extensive accumulation of Earth observations, it became possible to create a new global digital elevation product, the ASTER Global Digital Elevation Model (GDEM), using multi-temporal data, resulting in over 22,000 static 10 X 10 tiles. The ASTER GDEM was contributed by Japan’s Ministry of Economy Trade and Industry (METI) and the U.S. National Aeronautics and Space Administration (NASA) to the Global Earth Observation System of Systems (GEOSS) for distribution at no cost to users. As such, both METI and NASA desired to understand the uses of the ASTER GDEM, expressed as one of the GEOSS applications themes: disasters, health, energy, climate, water, weather, ecosystems, agriculture or biodiversity. This required both the registration of users, and restrictions on redistribution, to capture the intended use in terms of the GEOSS themes. The ASTER GDEM was made available to users worldwide via electronic download from the Earth Remote Sensing Data Analysis Center (ERSDAC) of Japan and from NASA’s Land Processes Distributed Active Archive Center (LP DAAC). During the first three months after product release, over 4 million GDEM tiles were distributed from the LP DAAC and ERSDAC. The ASTER GDEM release generated nearly 20,000 new user registrations in the NASA EOS ClearingHOuse (ECHO)/WIST and the ERSDAC systems. By the end of 2009, over 6.5 Million GDEM tiles were distributed by the LP DAAC and ERSDAC. Users have requested tiles over specific areas of interest as well as the entire dataset for global research. Intense global interest in the GDEM 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.

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

2010-12-01

101

Synergistic use of multitemporal RAMP, ICESat and GPS to construct an accurate DEM of the Larsemann Hills region, Antarctica  

NASA Astrophysics Data System (ADS)

An enhanced digital elevation model (DEM) of the Larsemann Hills region, east Antarctica, is constructed synergistically by using highly accurate ground-based GPS measurements, satellite-derived laser altimetry (GLAS/ICESat) and Radarsat Antarctic Mapping Project (RAMPv2) DEM-based point elevation dataset. Our DEM has a vertical accuracy of about 1.5 times better than RAMPv2 DEM and seven times better than GLAS/ICESAT-based DEM. The accuracy is improved by validating the RAMPv2 DEM elevation by supplementing with GLAS/ICESat and DGPS survey data, when compared to that of DEM constructed by using GLAS/ICESat or RAMPv2 alone. With the use of accurate GPS data as ground control points reference elevations, the DEM extracted is much more accurate with least mean RMSE of 34.5 m than that constructed by using a combination of GLAS/ICESat and RAMPv2 as true reference. The newly constructed DEM 7 achieves highest accuracy with the least average elevation difference of 0.27 m calculated using 46 ground reference points. Available DEMs of Antarctic region generated by using radar altimetry and the Antarctic Digital Database indicate elevation variations in the range of 50-100 m, which necessitates the generation of local DEM and its validation by using ground truth. This is our first attempt of fusing multi-temporal, multi-sensor and multi-source elevation data to generate a DEM of any part of Antarctica, in order to address the ice elevation change to infer the ice mass balance. Our approach focuses on the strengths of each elevation data source to produce an accurate DEM.

Jawak, Shridhar D.; Luis, Alvarinho J.

2012-08-01

102

Recent Release of the ASTER Global DEM Product  

NASA Astrophysics Data System (ADS)

On June 29th, the ASTER Global Digital Elevation Model (DEM) release was announced to the public and to a very eager audience. ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer) is an imaging instrument flying on Terra, a satellite launched in December 1999 as part of NASA's Earth Observing System (EOS). ASTER is a cooperative effort between NASA, Japan's Ministry of Economy, Trade and Industry (METI) and Japan's Earth Remote Sensing Data Analysis Center (ERSDAC). On June 21, NASA Headquarters along with colleagues in Japan (METI) signed a plan for distribution of this product. The global digital elevation model of Earth is available online to users everywhere at no cost from NASA's Land Processes Distributed Active Archive Center (DAAC) located at Sioux Falls, SD. The DAAC is a joint project of NASA and the USGS and is a key component of NASA's EOSDIS. The new ASTER GDEM was created from nearly 1.3 million individual stereo-pair images acquired by the Japanese Advanced Spaceborne Thermal Emission and Reflection Radiometer (Aster) instrument aboard NASA’s Terra satellite. The ASTER elevation model was jointly developed by NASA and METI under contract to Sensor Information Laboratory Corp., Tsukuba, Japan. On June 29, the NASA press release was picked up quickly by numerous news organizations and online sites. Response to the product was incredible! The news of the release of the product was carried on websites across the globe, this fueled a tremendous response from users. Here are a few interesting metrics about the release: - over 41,000 unique visitors to website in first week following release - top countries in order were: US (approx. 20%), Germany, U.K., Brazil, Austria, Canada, Spain, Switzerland, Japan - approximately 29,000 visitors came to the news page in the first week and about 11,000 of these users downloaded the actual press release - by the end of August, over 2 Million ASTER GDEM files had been downloaded from the Land Processes DAAC This presentation covers the issues associated with the release of this very popular product, including issues raised by many of our users.

Behnke, J.; Hall, A.; Meyer, D.; Sohre, T.; Doescher, C.

2009-12-01

103

Acute environmental toxicity and persistence of DEM, a chemical agent simulant: Diethyl malonate. [Diethyl malonate  

SciTech Connect

The purpose of the following chemical simulant studies is to assess the potential acute environmental effects and persistence of diethyl malonate (DEM). Deposition velocities for DEM to soil surfaces ranged from 0.04 to 0.2 cm/sec. For foliar surfaces, deposition velocities ranged from 0.0002 cm/sec at low air concentrations to 0.05 cm/sec for high dose levels. The residence times or half-lives of DEM deposited to soils was 2 h for the fast component and 5 to 16 h for the residual material. DEM deposited to foliar surfaces also exhibited biphasic depuration. The half-life of the short residence time component ranged from 1 to 3 h, while the longer time component had half-times of 16 to 242 h. Volatilization and other depuration mechanisms reduce surface contaminant levels in both soils and foliage to less than 1% of initial dose within 96 h. DEM is not phytotoxic at foliar mass loading levels of less than 10 {mu}m/cm{sup 2}. However, severe damage is evident at mass loading levels in excess of 17 {mu}g/cm{sup 2}. Tall fescue and sagebrush were more affected than was short-needle pine, however, mass loading levels were markedly different. Regrowth of tall fescue indicated that the effects of DEM are residual, and growth rates are affected only at higher mass loadings through the second harvest. Results from in vitro testing of DEM indicated concentrations below 500 {mu}g/g dry soil generally did not negatively impact soil microbial activity. Short-term effects of DEM were more profound on soil dehydrogenase activity than on soil phosphatase activity. No enzyme inhibition or enhancement was observed after 28 days in incubation. Results of the earthworm bioassay indicate survival to be 86 and 66% at soil doses of 107 and 204 {mu}g DEM/cm{sup 2}, respectively. At higher dose level, activity or mobility was judged to be affected in over 50% of the individuals. 21 refs., 10 figs., 15 tabs.

Cataldo, D.A.; Ligotke, M.W.; Harvey, S.D.; Fellows, R.J.; Li, Shu-mei W.; Van Voris, P.; Wentsel, R.S.

1990-05-01

104

Volume changes during the 2010 Merapi eruption calculated from TanDEM-X interferometry  

NASA Astrophysics Data System (ADS)

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 for local observatories are high. 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 bistatic German Earth observation mission TanDEM-X is of great importance to overcome some of these problems. Two almost identical radar satellites TerraSAR-X and TanDEM-X fly in a close formation, taking pictures of the same place on the Earth surface at the same time (bistatic mode). This results in two nearly absolutely coherent images. 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 DEMs derived in bistatic mode therefore opens the possibility to assess volume changes at active dome-building volcanoes. We analyze the volume changes due to the hazardous Merapi eruption in 2010. The eruption started on October 26, 2010. During the eruption, the 2006 lava dome was destroyed. A new lava dome was built and destroyed again at the end of the eruption in November 2010. We show a series of DEMs derived from Merapi by TanDEM-X SAR-interferometry taken before and after the 2010 eruption. The bistatic SAR images are acquired from ascending as well as descending orbits highlighting the NE-SE and NW-SW sectors of the edifice, respectively. We use the DEMs to give values of the volume change at the summit caused by the 2010 eruption. As the TanDEM-X mission is an innovative mission, the present study serves as a test to employ data of a new satellite mission in volcano research. An error analysis of the DEMs to evaluate the volume quantifications was therefore also conducted.

Kubanek, Julia; Westerhaus, Malte; Heck, Bernhard

2013-04-01

105

YADE-OPEN DEM: an open-source software using a discrete element method to simulate granular material  

Microsoft Academic Search

Purpose – YADE-OPEN DEM is an open-source software based on the discrete element method, (DEM) which uses object oriented programming techniques. The purpose of this paper is to describe the software architecture. Design\\/methodology\\/approach – The DEM chosen uses position, orientation, velocity and angular velocity as independent variables of simulated particles which are subject to explicit leapfrog time-integration scheme (Lagrangian method).

J. Kozicki; F. V. Donzé

2009-01-01

106

TecDEM: A MATLAB Based Toolbox for understanding Tectonics from Digital Elevation Models  

NASA Astrophysics Data System (ADS)

TecDEM is a MATLAB based tool box for understanding the tectonics from digital elevation models (DEMs) of any area. These DEMs can be derived from data of any spatial resolution (Low, medium and High). In the first step we extract drainage network from the DEMs using flow grid approach. Drainage network is a group of streams having elevation and catchment area information as a function of spatial locations. We implement an array of stream structure to study this drainage network. Knickpoints can be identified on each stream of the drainage network by a graphical user interface and are helpful for understanding stream morphology. Stream profile analysis in steady state condition is applied on all streams to calculate geomorphic parameters and regional uplift rates. Hack index is calculated for all the profiles at a certain interval and over the change of knickpoints. Reports menu of this tool box generates detailed statistics report, complete tabulated report, graphical output of each analyzed stream profile and Hack index profile. All the calculated values are part of stream structure and is saved as .mat file for later use with this tool box. The spatial distribution of geomorphic parameters, uplift rates and knickpoints are exported as a shape files for visualization in professional GIS software. We test this tool box on DEMs from different tectonic settings worldwide and received verifiable results with other studies.

Shahzad, F.; Mahmood, S. A.; Gloaguen, R.

2009-04-01

107

Optimizing grid computing configuration and scheduling for geospatial analysis: An example with interpolating DEM  

NASA Astrophysics Data System (ADS)

Many geographic analyses are very time-consuming and do not scale well when large datasets are involved. For example, the interpolation of DEMs (digital evaluation model) for large geographic areas could become a problem in practical application, especially for web applications such as terrain visualization, where a fast response is required and computational demands exceed the capacity of a traditional single processing unit conducting serial processing. Therefore, high performance and parallel computing approaches, such as grid computing, were investigated to speed up the geographic analysis algorithms, such as DEM interpolation. The key for grid computing is to configure an optimized grid computing platform for the geospatial analysis and optimally schedule the geospatial tasks within a grid platform. However, there is no research focused on this. Using DEM interoperation as an example, we report our systematic research on configuring and scheduling a high performance grid computing platform to improve the performance of geographic analyses through a systematic study on how the number of cores, processors, grid nodes, different network connections and concurrent request impact the speedup of geospatial analyses. Condor, a grid middleware, is used to schedule the DEM interpolation tasks for different grid configurations. A Kansas raster-based DEM is used for a case study and an inverse distance weighting (IDW) algorithm is used in interpolation experiments.

Huang, Qunying; Yang, Chaowei

2011-02-01

108

A beginner's guide to stereo-derived DEM production and analysis using ISIS, ASP, and ArcMap  

E-print Network

A beginner's guide to stereo-derived DEM production and analysis using ISIS, ASP, and ArcMap v. 1 ............................................................................................................................5 2. Processing the images with ISIS

Rathbun, Julie A.

109

FEM × DEM modelling of cohesive granular materials: Numerical homogenisation and multi-scale simulations  

NASA Astrophysics Data System (ADS)

The article presents a multi-scale modelling approach of cohesive granular materials, its numerical implementation and its results. At microscopic level, Discrete Element Method (DEM) is used to model dense grains packing. At the macroscopic level, the numerical solution is obtained by a Finite Element Method (FEM). In order to bridge the micro- and macro-scales, the concept of Representative Elementary Volume (REV) is applied, in which the average REV stress and the consistent tangent operators are obtained in each macroscopic integration point as the results of DEM's simulation. In this way, the numerical constitutive law is determined through the detailed modelling of the microstructure, taking into account the nature of granular materials. We first elaborate the principle of the computation homogenisation (FEM × DEM), then demonstrate the features of our multiscale computation in terms of a biaxial compression test. Macroscopic strain location is observed and discussed.

Nguyen, Trung Kien; Combe, Gaël; Caillerie, Denis; Desrues, Jacques

2014-10-01

110

TanDEM-X: A radar interferometer with two formation-flying satellites  

NASA Astrophysics Data System (ADS)

TanDEM-X (TerraSAR-X add-on for Digital Elevation Measurements) is an innovative formation-flying radar mission that opens a new era in spaceborne radar remote sensing. The primary objective is the acquisition of a global digital elevation model (DEM) with unprecedented accuracy (12 m horizontal resolution and 2 m relative height accuracy). This goal is achieved by extending the TerraSAR-X synthetic aperture radar (SAR) mission by a second, TerraSAR-X like satellite (TDX) flying in close formation with TerraSAR-X (TSX). Both satellites form together a large single-pass SAR interferometer with the opportunity for flexible baseline selection. This enables the acquisition of highly accurate cross-track interferograms without the inherent accuracy limitations imposed by repeat-pass interferometry due to temporal decorrelation and atmospheric disturbances. Besides the primary goal of the mission, several secondary mission objectives based on along-track interferometry as well as new bistatic and multistatic SAR techniques have been defined, representing an important and innovative asset of the TanDEM-X mission. TanDEM-X is implemented in the framework of a public-private partnership between the German Aerospace Center (DLR) and EADS Astrium GmbH. The TanDEM-X satellite was successfully launched in June 2010 and the mission started its operational data acquisition in December 2010. This paper provides an overview of the TanDEM-X mission and summarizes its actual status and performance. Furthermore, results from several scientific radar experiments are presented that show the great potential of future formation-flying interferometric SAR missions to serve novel remote sensing applications.

Krieger, Gerhard; Zink, Manfred; Bachmann, Markus; Bräutigam, Benjamin; Schulze, Daniel; Martone, Michele; Rizzoli, Paola; Steinbrecher, Ulrich; Walter Antony, John; De Zan, Francesco; Hajnsek, Irena; Papathanassiou, Kostas; Kugler, Florian; Rodriguez Cassola, Marc; Younis, Marwan; Baumgartner, Stefan; López-Dekker, Paco; Prats, Pau; Moreira, Alberto

2013-08-01

111

Discrete Element Method (DEM) Application to The Cone Penetration Test Using COUPi Model  

NASA Astrophysics Data System (ADS)

The cone penetration test (CPT) is a soil strength measurement method to determine the tip resistance and sleeve friction versus depth while pushing a cone into regolith with controlled slow quasi-static speed. This test can also be used as an excellent tool to validate the discrete element method (DEM) model by comparing tip resistance and sleeve friction from experiments to model results. DEM by nature requires significant computational resources even for a limited number of particles. Thus, it is important to find particle and ensemble parameters that produce valuable results within reasonable computation times. The Controllable Objects Unbounded Particles Interaction (COUPi) model is a general physical DEM code being developed to model machine/regolith interactions as part of a NASA Lunar Science Institute sponsored project on excavation and mobility modeling. In this work, we consider how different particle shape and size distributions defined in the DEM influence the cone tip and friction sleeve resistance in a CPT DEM simulation. The results are compared to experiments with cone penetration in JSC-1A lunar regolith simulant. The particle shapes include spherical particles, particles composed from the union of three spheres, and some simple polyhedra. This focus is driven by the soil mechanics rule of thumb that particle size and shape distributions are the two most significant factors affecting soil strength. In addition to the particle properties, the packing configuration of an ensemble strongly affects soil strength. Bulk density of the regolith is an important characteristic that significantly influences the tip resistance and sleeve friction (Figure 1). We discuss different approaches used to control granular density in the DEM, including how to obtain higher bulk densities, using numerical "shaking" techniques and varying the friction coefficient during computations.

Kulchitsky, A. V.; Johnson, J.; Wilkinson, A.; DeGennaro, A. J.; Duvoy, P.

2011-12-01

112

Quality assessment of Digital Elevation Model (DEM) in view of the Altiplano hydrological modeling  

NASA Astrophysics Data System (ADS)

Topography is crucial data input for hydrological modeling but in many regions of the world, the only way to characterize topography is the use of satellite-based Digital Elevation Models (DEM). In some regions, the quality of these DEMs remains poor and induces modeling errors that may or not be compensated by model parameters tuning. In such regions, the evaluation of these data uncertainties is an important step in the modeling procedure. In this study, which focuses on the Altiplano region, we present the evaluation of the two freely available DEM. The shuttle radar topographic mission (SRTM), a product of the National Aeronautics and Space Administration (NASA) and the Advanced Space Born Thermal Emission and Reflection Global Digital Elevation Map (ASTER GDEM), data provided by the Ministry of Economy, Trade and Industry of Japan (MESI) in collaboration with the NASA, are widely used. While the first represents a resolution of 3 arc seconds (90m) the latter is 1 arc second (30m). In order to select the most reliable DEM, we compared the DEM elevation with high qualities control points elevation. Because of its large spatial coverture (track spaced of 30 km with a measure of each 172 m) and its high vertical accuracy which is less than 15 cm in good weather conditions, the Geoscience Laser Altimeter System (GLAS) on board on the Ice, Cloud and Land elevation Satellite of NASA (ICESat) represent the better solution to establish a high quality elevation database. After a quality check, more than 150 000 ICESat/GLAS measurements are suitable in terms of accuracy for the Altiplano watershed. This data base has been used to evaluate the vertical accuracy for each DEM. Regarding to the full spatial coverture; the comparison has been done for both, all kind of land coverture, range altitude and mean slope.

Satgé, F.; Arsen, A.; Bonnet, M.; Timouk, F.; Calmant, S.; Pilco, R.; Molina, J.; Lavado, W.; Crétaux, J.; HASM

2013-05-01

113

How large is the Upper Indus Basin? The pitfalls of auto-delineation using DEMs  

NASA Astrophysics Data System (ADS)

Extraction of watershed areas from Digital Elevation Models (DEMs) is increasingly required in a variety of environmental analyses. It is facilitated by the availability of DEMs based on remotely sensed data, and by Geographical Information System (GIS) software. However, accurate delineation depends on the quality of the DEM and the methodology adopted. This paper considers automated and supervised delineation in a case study of the Upper Indus Basin (UIB), Pakistan, for which published estimates of the basin area show significant disagreement, ranging from 166,000 to 266,000 km2. Automated delineation used ArcGIS Archydro and hydrology tools applied to three good quality DEMs (two from SRTM data with 90m resolution, and one from 30m resolution ASTER data). Automatic delineation defined a basin area of c.440,000 km2 for the UIB, but included a large area of internal drainage in the western Tibetan Plateau. It is shown that discrepancies between different estimates reflect differences in the initial extent of the DEM used for watershed delineation, and the unchecked effect of iterative pit-filling of the DEM (going beyond the filling of erroneous pixels to filling entire closed basins). For the UIB we have identified critical points where spurious addition of catchment area has arisen, and use Google Earth to examine the geomorphology adjacent to these points, and also examine the basin boundary data provided by the HydroSHEDS database. We show that the Pangong Tso watershed and some other areas in the western Tibetan plateau are not part of the UIB, but are areas of internal drainage. Our best estimate of the area of the Upper Indus Basin (at Besham Qila) is 164,867 km2 based on the SRTM DEM, and 164,853 km2 using the ASTER DEM). This matches the catchment area measured by WAPDA SWHP. An important lesson from this investigation is that one should not rely on automated delineation, as iterative pit-filling can produce spurious drainage networks and basins, when there are areas of internal drainage nearby.

Khan, Asif; Richards, Keith S.; Parker, Geoffrey T.; McRobie, Allan; Mukhopadhyay, Biswajit

2014-02-01

114

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

PubMed Central

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. PMID:22573996

Gao, Yongnian; Zhang, Wanchang

2009-01-01

115

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

NASA Astrophysics Data System (ADS)

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 delimiting coastline, avoiding the confusion between elevation and no-data values. Six (from March 2005 to May 2007) geometrically corrected Landsat-5 images on the path-row 197-031 have been used. The six optical bands and the NDVI for each date have been introduced in a powerful hybrid classification process. The training areas and the ground truth have been obtained from the Mapa de Cobertes del Sòl de Catalunya (v. 3), a land cover map created by photointerpretation of 0.5 m orthophotomaps acquired between 2005 and 2007 and covering all the extension of Catalonia. The legend has been reduced from 233 categories to 21. Preliminary results have shown that the effect on land cover classification of applying lossy compression to the DEM used in the radiometric correction is small (lower than 1%) even for compression ratios up to 200:1. Comparing classification performance after a compression of 5:1 and and a compression of 200:1 with both coding standards showed that: a) the percentage of correctly classified image was 73%; b) 20% was wrongly classified; c) 3.5% was wrongly classified at compression ratio 5:1; and d) also 3.5% was wrongly classified at compression ratio 200:1. These results are the first in the literature to analyze the effect of DEM lossy compressing when DEM are employed for radiometric correction.

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

2012-12-01

116

DEM simulation of industrial particle flows: case studies of dragline excavators, mixing in tumblers and centrifugal mills  

Microsoft Academic Search

Discrete element methods (DEM) are now sufficiently well developed to plausibly model industrial and mining related particle flows. Three cases studies of such DEM simulations are presented here; dragline excavators, mixing in tumblers and charge motion in centrifugal mills. They show the breadth of application now possible and the types of predictions that can be made for each. More importantly,

Paul W. Cleary

2000-01-01

117

Simulation of dilute pneumatic conveying with different types of bends by CFD-DEM  

NASA Astrophysics Data System (ADS)

Bends are one of the most commonly used facilities to change flow direction in pneumatic conveying. It is important to understand the effect of the bend to the gas-solid flow structures in a pneumatic conveying system. CFD-DEM is one of powerful methods to study the fundamentals of gas-solid flow, as it takes the particle-particle and particle-wall collisions into account. But the time consumption is one of major limitations for its application. In this paper, a three-dimensional CFD-DEM model which ignores the effect of void fraction to the gas phase is used to simulate the dilute gas-solid flow. Gas-solid flows in different types of bends including horizontal-vertical, vertical-horizontal and horizontal-horizontal 90° bends are studied. The present CFD-DEM model is verified by compared the rope structure with the result for traditional CFD-DEM model in horizontal-vertical case. Compared the particle rope dispersion in different types of bends, the rope disperses more quickly in the vertical-horizontal case than others, and the solid flow structure is the most complicated in the horizontal- horizontal case. As their various solid flow structures, the collision data of three cases also seem different.

Du, J.; Hu, G. M.; Fang, Z. Q.; Wang, J.

2014-12-01

118

Macromolecular Structure Modeling from 3DEM Using VOLROVER 2.01  

E-print Network

for 3DEM structure identification and model-based refinement developed by our research group research groups. The comparisons show that our software is capable of segmenting relatively accurate-Portugal-Colab project. #12;2 1 Introduction Humans have made a great deal of progress in revealing the structures

Texas at Austin, University of

119

Determination of coalescence kernels for high-shear granulation using DEM simulations  

Microsoft Academic Search

Discrete element method (DEM) modeling is used in parallel with a model for coalescence of deformable surface wet granules. This produces a method capable of predicting both collision rates and coalescence efficiencies for use in derivation of an overall coalescence kernel. These coalescence kernels can then be used in computationally efficient meso-scale models such as population balance equation (PBE) models.

Justin A. Gantt; Ian T. Cameron; James D. Litster; Edward P. Gatzke

2006-01-01

120

Improving Soil Salinity Prediction with High Resolution DEM Derived from LiDAR Data  

Microsoft Academic Search

The aim of this study is to investigate the capability of integration of LiDAR derived terrain and hydrological features with other salinity related datasets to improve prediction of areas at risk from salinity in a catchment area in Victoria, Australia. Terrain and hydrological features including slope, drainage density and hilltop were generated from LiDAR derived DEM and a relative low

Xiaoye Liu; Jim Peterson; Zhenyu Zhang; Shobhit Chandra

2005-01-01

121

Web Service for Extracting Stream Networks from DEM Data , I. Molloyc  

E-print Network

referred to as hydrology based algorithms) are generally adequate for small scale watershed or in places criteria to separate channels and hillslope. However, these hydrology based algorithms often tend describes the implementation of a morphology based algorithm for extracting stream networks from DEM data

Stepinski, Tomasz F.

122

Kulturindustrielle Politik mit dem Großen & Ganzen: Populismus, Politik-Darsteller, ihr Publikum und seine Mobilisierung  

Microsoft Academic Search

ielleicht war »Populismus« einmal ein analy- tischer Begriff, mit dem sich eine Form von Politik beschreiben ließ. Ich habe meine Zweifel. Wenn überhaupt, dann war das nur kurz der Fall und das ist lang her. Die üblichen Hinweise auf verschiedene »Volkstümler« in Amerika und Ruß- land haben selbst eher folkloristischen Charakter, indem sie genauso stereotyp wiederholt werden wie die Floskeln

HEINZ STEINERT

123

90-METER DIGITAL ELEVATION MODEL (DEM) FOR THE MID-ATLANTIC INTEGRATED ASSESSMENT (MAIA) STUDY AREA  

EPA Science Inventory

This data set is a geographic information system (GIS) coverage of the 90-meter digital elevation model (DEM) for the United States Environmental Protection Agency (USEPA) Mid-Atlantic Integrated Assessment (MAIA) Project region. The coverage was produced using US Geological Su...

124

DETERMINING WATERSHED BOUNDARIES AND AREA USING GPS, DEMS, AND TRADITIONAL METHODS: A COMPARISON  

E-print Network

DETERMINING WATERSHED BOUNDARIES AND AREA USING GPS, DEMS, AND TRADITIONAL METHODS: A COMPARISON Boris Poff Duncan Leao,Aregai Teele,and Daniel G.Neary Defining a watershed's boundary is critical for understanding the movement of water across the landscape. In the past, hydrolo- gists defined watersheds using

125

Mit dem Namen Charles Darwin verbinden sich immer auch die nach ihm benannten  

E-print Network

Mit dem Namen Charles Darwin verbinden sich immer auch die nach ihm benannten Darwinfinken auf den entwickelten weitgehend übereinstimmt. Seitdem Charles Darwin seine �berle- gungen nach langen Jahren des wissenschaftshistori- schen Bedeutung von Charles Darwin. Er beschreibt, wie Darwin ein neues Verständ- nis von der

126

Neufunde von Sycidium G. Sandberger (nova class., Charophyta?) aus dem Devon der Eifel  

Microsoft Academic Search

Zusammenfassung  Beschreibung vonSycidium volborthi eijelicum nov. subsp. undSycidium cf. reticulatum G. Sandberger aus dem Mittel-Devon. Der Nachweis von Poren führt zu einer erneuten Kurzdiskussion über die systematisch problematische\\u000a Stellung der Gruppe (Sycidiphyceae nova class.). Notizen zur Ökologie.

W. Langer Bonn

1976-01-01

127

From Point Cloud to Grid DEM: A Scalable Pankaj K. Agarwal 1  

E-print Network

From Point Cloud to Grid DEM: A Scalable Approach Pankaj K. Agarwal 1 , Lars Arge 12 , and Andrew) in about 53 hours. Neither ArcGIS nor GRASS, two popular GIS products, were able to process this data set. 1 Introduction One of the basic tasks of a geographic information system (GIS) is to store a repre

Danner, Andrew

128

Representative hillslope methods for applying the WEPP model with DEMs and GIS  

Technology Transfer Automated Retrieval System (TEKTRAN)

Modeling procedures called the Hillslope methods were developed that use geographical information systems (GIS) and digital elevation models (DEMs) to assess water erosion in small watersheds with the Water Erosion Prediction Project (WEPP) model. The Hillslope methods are automated procedures to d...

129

Combining DEM parameters with Landsat MSS and TM imagery in a GIS for mountain glacier characterization  

Microsoft Academic Search

The building of a glaciological database is explored as an answer to the management of multisource and multiscale information required for the study of mountain glacier variations. Topographic information is derived from the 1:250,000 scale digital elevation model (DEM) of the Surveys and Mapping Branch of Energy, Mines and Resources, Canada. The interfacing of a geographic information system (GIS) and

Denis J. Gratton; Philip J. Howarth; Danielle J. Marceau

1990-01-01

130

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

PubMed

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. PMID:21301958

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

2011-11-01

131

The integration of spectral analyses of Landsat ETM+ with the DEM data for mapping mangrove forests  

Microsoft Academic Search

This study aims to develop an efficient method to extract mangrove forests at a regional scale using remote sensing data and Geographic Information Systems (GIS) technique. A regional mangrove forests mapping method was developed based on the spectral characteristics and the topographic existence condition of mangrove forests. Landsat Enhanced Thematic Mapper plus (ETM+) and digital elevation model (DEM) were used

Bayan Alsaaideh; Ahmad Al-Hanbali; Ryutaro Tateishi; Hoan Nguyen Thanh

2011-01-01

132

Untersuchung der Drei-Eichboson-Kopplungen mit dem OPAL-Detektor bei LEP  

E-print Network

Untersuchung der Drei-Eichboson-Kopplungen mit dem OPAL-Detektor bei LEP Diplomarbeit von Wolfgang of the Trilinear Gauge Boson Couplings with the OPAL Detector at LEP Abstract In this work an analysis, collected with the OPAL detector at a centre-of-mass energy of 189 GeV. One obtain: #1;g Z 1 = 0:076 +0

133

A simplified DEM-CFD approach for pebble bed reactor simulations  

SciTech Connect

In pebble bed reactors (PBR's), the pebble flow and the coolant flow are coupled with each other through coolant-pebble interactions. Approaches with different fidelities have been proposed to simulate similar phenomena. Coupled Discrete Element Method-Computational Fluid Dynamics (DEM-CFD) approaches are widely studied and applied in these problems due to its good balance between efficiency and accuracy. In this work, based on the symmetry of the PBR geometry, a simplified 3D-DEM/2D-CFD approach is proposed to speed up the DEM-CFD simulation without significant loss of accuracy. Pebble flow is simulated by a full 3-D DEM, while the coolant flow field is calculated with a 2-D CFD simulation by averaging variables along the annular direction in the cylindrical geometry. Results show that this simplification can greatly enhance the efficiency for cylindrical core, which enables further inclusion of other physics such as thermal and neutronic effect in the multi-physics simulations for PBR's. (authors)

Li, Y.; Ji, W. [Dept. of Mechanical, Aerospace and Nuclear Engineering, Rensselaer Polytechnic Inst., JEC 5040 MANE, 110 8th Street, Troy, NY 12180 (United States)

2012-07-01

134

A problem-oriented approach for DEM data management and manipulation  

NASA Astrophysics Data System (ADS)

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.

Huang, Fengru; Fang, Yu; Chen, Bin

2009-10-01

135

A problem-oriented approach for DEM data management and manipulation  

NASA Astrophysics Data System (ADS)

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.

Huang, Fengru; Fang, Yu; Chen, Bin

2008-10-01

136

Hydrology, secondary growth, and elevation accuracy in two preliminary Amazon Basin SRTM DEMs  

NASA Astrophysics Data System (ADS)

Two preliminary Shuttle Radar Topography Mission digital elevation models (SRTM DEMs) of Manaus (1S to 5S and 59W to 63W) and Rondonia (9S to 12S and 61W to 64W) were received from the "PI Processor" at NASA JPL. We compared the Manaus DEM (C-band) with a previously constructed Cabaliana floodplain classification based on Global RainForest Mapping (GRFM) JERS-1 SAR data (L-band) and determined that habitats of open water, bare ground, and flooded shrub contained the lowest elevations; macrophyte and non-flooded shrub habitats are marked by intermediate elevations; and the highest elevations are found within flooded and non-flooded forest. Although the water surface typically produces specular reflections, double-bounce travel paths result from dead, leafless trees found across the Balbina reservoir near Manaus. There (i.e., in Balbina) the water surface is marked by pixel-to-pixel height changes of generally 0 to 1 m and changes across a ˜100 km transect rarely exceed 3 m. Reported SRTM errors throughout the transect range from 1 to 2 m with some errors up to 5 m. The smooth Balbina surface contrasts with the wind-roughened Amazon River surface where SRTM height variations easily range from 1 to 10 m (reported errors often exceed 5 m). Deforestation and subsequent regrowth in the Rondonia DEM is remarkably clear. Our colleagues used a 20 year sequence of Landsat TM/MSS classified imagery to delineate areas in various stages of secondary growth and we find a general trend of increasing vegetation height with increasing age. Flow path networks derived from the Cabaliana floodplain DEM are in general agreement with networks previously extracted from the GRFM mosaics; however, watershed boundaries differ. We have also developed an algorithm for extracting channel widths, which is presently being applied to the DEM and classified imagery to determine morphological variations between reaches.

Alsdorf, D.; Hess, L.; Sheng, Y.; Souza, C.; Pavelsky, T.; Melack, J.; Dunne, T.; Hendricks, G.; Ballantine, A.; Holmes, K.

2003-04-01

137

Fusion of high-resolution DEMs derived from COSMO-SkyMed and TerraSAR-X InSAR datasets  

NASA Astrophysics Data System (ADS)

Voids caused by shadow, layover, and decorrelation usually occur in digital elevation models (DEMs) of mountainous areas that are derived from interferometric synthetic aperture radar (InSAR) datasets. The presence of voids degrades the quality and usability of the DEMs. Thus, void removal is considered as an integral part of the DEM production using InSAR data. The fusion of multiple DEMs has been widely recognized as a promising way for the void removal. Because the vertical accuracy of multiple DEMs can be different, the selection of optimum weights becomes a key problem in the fusion and is studied in this article. As a showcase, two high-resolution InSAR DEMs near Mt. Qilian in northwest China are created and then merged. The two pairs of InSAR data were acquired by TerraSAR-X from an ascending orbit and COSMO-SkyMed from a descending orbit. A maximum likelihood fusion scheme with the weights optimally determined by the height of ambiguity and the variance of phase noise is adopted to syncretize the two DEMs in our study. The fused DEM has a fine spatial resolution of 10 m and depicts the landform of the study area well. The percentage of void cells in the fused DEM is only 0.13 %, while 6.9 and 5.7 % of the cells in the COSMO-SkyMed DEM and the TerraSAR-X DEM are originally voids. Using the ICESat/GLAS elevation data and the Chinese national DEM of scale 1:50,000 as references, we evaluate vertical accuracy levels of the fused DEM as well as the original InSAR DEMs. The results show that substantial improvements could be achieved by DEM fusion after atmospheric phase screen removal. The quality of fused DEM can even meet the high-resolution terrain information (HRTI) standard.

Jiang, Houjun; Zhang, Lu; Wang, Yong; Liao, Mingsheng

2014-06-01

138

Thirty-meter digital elevation models (DEMs) produced by the U.S. Geological Survey (USGS) are widely available and com-  

E-print Network

Abstract Thirty-meter digital elevation models (DEMs) produced by the U.S. Geological Survey (USGS, and slope classes gen- erated from sample 10-meter drainage-enforced (DE) DEMs and 30-meter DEMs. We found increasing resolution from 30 meters to 10 me- ters, particularly in flatter terrain; (2) streams and HU

139

Detailed geomorphological mapping from high resolution DEM data (LiDAR, TanDEM-X): two case studies from Germany and SE Tibet  

NASA Astrophysics Data System (ADS)

Two major obstacles are hampering the production of high resolution geomorphological maps: the complexity of the subject that should be depicted and the enormous efforts necessary to obtain data by field work. The first factor prevented the establishment of a generally accepted map legend; the second hampered efforts to collect comprehensive sets of geomorphological data. This left geomorphologists to produce applied maps, focusing on very few layers of information and often not sticking to any of the numerous standards proposed in the second half of the 20th century. Technological progress of the recent years, especially in the fields of digital elevation models, GIS environments, and computational hardware, today offers promising opportunities to overcome the obstacles and to produce detailed geomorphological maps even for remote or inhospitable regions. The feasibility of detailed geomorphological mapping from two new sets of digital elevation data, the 1 m LiDAR DTM provided by Germany's State Surveying Authority and the upcoming TanDEM-X DEM, has been evaluated in two case studies from a low mountain range in Germany and a high mountain range in SE Tibet. The results indicate that most layers of information of classical geomorphological maps (e.g. the German GMK) can be extracted from this data at appropriate scales but that significant differences occur concerning the quality and the grades of certainty of key contents. Generally, an enhancement of the geomorphographical, especially the geomorphometrical, and a weakening of geomorphogenetical contents was observed. From these findings, theoretical, methodological, and cartographical remarks on detailed geomorphological mapping from DEM data in GIS environments were educed. As GIS environments decouple data and design and enable the geomorphologist to choose information layer combinations freely to fit research topics, a general purpose legend becomes obsolete. Yet, a unified data structure is demanded to ensure that data collected by different scientists or in different studies can be exchanged and reused.

Loibl, D.

2012-04-01

140

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

NASA Astrophysics Data System (ADS)

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.

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

2014-03-01

141

On Impact Penetration Analysis and Evaluation of Brittle Material Plate Using Three-Dimensional DEM  

NASA Astrophysics Data System (ADS)

It is important to know the impact fracture behaviors in the safety design of the brittle material board. However, the three-dimensional analysis for the impact fracture behaviors of the brittle material board is not done over the current. In this research, the impact penetration fracture when the impact body collides with the center of the brittle material board is analyzed by PFC3D. It is the general three-dimensional program that uses the Distinct Element Method (DEM). DEM is suitable for the analysis of the fracture behavior of the non-individual body and the break-up body. The analytical results are compared with the experimental one and the validity of analytical results are checked. By this research, it is obvious that the penetration speed and the loss energy increase as the impact velocity, radius and mass of the impact body increase. Moreover, the relations between the parameters of impact body and fracture behavior are clarified.

Oda, Juhachi; Yasuda, Hiroto

142

DEM generation and tidal deformation detection for sulzberger ice shelf, West Antarctica using SAR interferometry  

USGS Publications Warehouse

In this study we generated a relative Digital Elevation Model (DEM) over the Sulzberger Ice Shelf, West Antarctica using ERS1/2 synthetic aperture radar (SAR) interferometry data. Four repeat pass differential interferograms are used to find the grounding zone and to classify the study area. An interferometrically derived DEM is compared with laser altimetry profile from ICESat. Standard deviation of the relative height difference is 5.12 m and 1.34 m in total length of the profile and at the center of the profile respectively. The magnitude and the direction of tidal changes estimated from interferogram are compared with those predicted tidal differences from four ocean tide models. Tidal deformation measured in InSAR is -16.7 cm and it agrees well within 3 cm with predicted ones from tide models.

Baek, S.; Kwoun, O.-I.; Bassler, M.; Lu, Z.; Shum, C.K.; Dietrich, R.

2004-01-01

143

Asperity Degradation and Damage in the Direct Shear Test: A Hybrid FEM\\/DEM Approach  

Microsoft Academic Search

Summary  This paper investigates the processes of joint surface damage and near-surface intact rock tensile failure using a hybrid\\u000a FEM\\/DEM code. Selected Barton and Choubey JRC profiles were simulated in direct shear tests and the surface damage mechanisms\\u000a investigated in terms of joint surface wear or tensile fracturing of intact rock along the joint plane. Shear strength and\\u000a displacement profiles for

A. Karami; D. Stead

2008-01-01

144

Franz Schubert Der Hirt auf dem Felsen D. 965 (1828) (1797-1828)  

E-print Network

/11 8:00pm Visiting Artists Borromeo String Quartet Brooks-Rogers Recital Hall 4/15 4:15pm Class of 1960Franz Schubert Der Hirt auf dem Felsen D. 965 (1828) (1797-1828) Erin Nafziger, soprano; Susan Brooks-Rogers Recital Hall 3/15 8:00pm Visiting Artists Jimmy Greene Quartet Brooks-Rogers Recital Hall 3

Aalberts, Daniel P.

145

Anwendung der Massenspektrometrie zur Strukturaufklärung von Alkaloiden, 6. Mitt.: Pyrrolizidinalkaloide aus dem Goldregen  

Microsoft Academic Search

Im Samen des Goldregens konnten mit Hilfe der Massenspektrometrie neben dem bereits früher aufgefundenen und in seiner Konstitution aufgeklärten2, 3 Pyrrolizidin-alkaloid Laburnin noch zwei weitere Alkaloide als Vertreter dieses Skelett-typus erkannt werden: ein ebenfalls schon früher isoliertes, aber in seiner Struktur noch nicht bekanntes Alkaloid der Summenformel C12H22N2O4, für das wir nun den Namen Laburnamin vorschlagen, und ein 1-Hydroxymethyl-7-hydroxypyrrolizidin (Platynecin

N. Neuner-Jehle; H. Nesvadba; G. Spiteller

1965-01-01

146

Michael Zimmer’s Diary: Ein deutsches Tagebuch aus dem Amerikanischen Biirgerkrieg  

E-print Network

deutsches Tagebuch aus dem Amerikanischen Bürgerkrieg.” Edited by Jürgen Macha and Andrea Wolf. Yearbook of German-American Studies 40 (2005): 174-176 Terms of Use: http://www2.ku.edu/~scholar/docs/license.shtml YEARBOOK OF GERMAN-AMERICAN STUDIES Volume... Experiences During the Indian Uprising in Minnesota Don Heinrich Tolzmann, trans, and ed. Reviewed by Timothy J. Holian 171 Philip Otterness Becoming German: The 1709 Palatine Migration to New York Reviewed by J. Gregory Redding 173 Jiirgen Macha...

Keel, William

2005-01-01

147

A 'Drift' algorithm for integrating vector polyline and DEM based on the spherical DQG  

NASA Astrophysics Data System (ADS)

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.

Wang, Jiaojiao; Wang, Lei; Cao, Wenmin; Zhao, Xuesheng

2014-03-01

148

MFIX-DEM simulations of change of volumetric flow in fluidized beds due to chemical reactions  

Microsoft Academic Search

This study attempts to investigate the effect of gas volume change caused by chemical reactions on the flow hydrodynamics in a fluidized bed reactor. Various 2D simulations of ozone decomposition and the reverse reaction are conducted with a Eulerian–Lagrangian code-MFIX-DEM for a small-scale bubbling fluidized bed. The effect of particle size is studied by simulating two types of bed material

Tingwen Li; Chris Guenther

149

Von und ber Albert Einstein aus dem Bibliotheksbestand des kiz der Universitt Ulm  

E-print Network

Von und über Albert Einstein aus dem Bibliotheksbestand des kiz der Universität Ulm Titel Autor Synthese Madary, Carl Alberti 1921 J96: B 3500/1921 M Akademie-Vorträge Einstein, Albert Treder, Hans- Jürgen Akademie-Verl. 1979 BZ: p QC 3/1979 E Ex.2 W: p QC 3/1979 E Albert Einstein: sein Einflu� auf

Pfeifer, Holger

150

Combining ICESat altimetry and SPIRIT SPOT5 DEMs to detect recent elevation changes of Svalbard glaciers  

NASA Astrophysics Data System (ADS)

Estimation of recent glacier elevation changes in Svalbard is dependent upon the availability and overlap of geodetic data within the past decades. The ICESat altimeter has been a semi-continuous provider of elevation data between 2003 and 2008, though repeat track ICESat comparisons over rugged glacier terrain, like Svalbard, is complicated due to the unknown cross track slope. We test two methods of repeat track analysis to derive 2003-2008 elevation changes over Svalbard glaciers. The first method uses SPIRIT SPOT5 DEMs to correct for the cross track slope while the second method estimates slope and aspect along with elevation change using ICESat data only. The results are compared to decadal elevation change rates estimated by differencing older Norwegian Polar Institute maps, a 1990 DEM, and SPIRIT SPOT5 DEMs. Long term comparisons indicate that the rate of thinning has increased over the past 50 years, however, elevation change rates from 2003 to 2008 are less negative than the long term average.

Moholdt, G.; Nuth, C.; Kääb, A.; Kohler, J.

2009-12-01

151

Suitability of COSMO-SkyMed constellation for radargrammetric DEM generation  

NASA Astrophysics Data System (ADS)

The COSMO-SkyMed (CSK) constellation acquires data from its four SAR X-band satellites in several imaging modes, providing in particular different view angles. The present work investigates the potential of CSK constellation for ground elevation measurement through SAR radargrammetry. We selected an area around Parkfield (California), where several CSK acquisitions are available. We used for radargrammetric processing 2 CSK spotlight image pairs acquired at 1 day of separation, in Same Side Viewing configuration, with baselines of 350 km. Furthermore, a dataset of 33 spotlight images were selected to derive height measurements through both persistent scatterers interferometry(PSI) and interferometric processing of 5 1-day separated pairs included in the dataset. We first predict how the errors in the geometrical parameters and the correlation level between the images impact on the height accuracy. Then, two DEMs were derived by processing the radargrammetric CSK pairs. According to the outcomes of the feasibility analysis, processing parameters were chosen in order to guarantee nominal values of height accuracy within the HRTI Level 3 specifications. The products have a final resolution of 3 m. In order to assess the accuracy of these radargrammetric DEMs, we used the height values provided by the PSI, and an interferometric DEM derived from the CSK tandem-like pairs.

Conte, Domenico; Bovenga, Fabio; Refice, Alberto; Nitti, Davide O.; Nutricato, Raffaele; Chiaradia, Maria T.

2014-10-01

152

Detection and evaluation on phosphorite mining environment contamination sources using ASTER and DEM  

NASA Astrophysics Data System (ADS)

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.

Chen, Wei-tao; Zhang, Zhi; Li, Zhi-zhong; Yang, Jun-jie; Qian, Li-ping

2008-11-01

153

Creating Shaded Relief Images and 3D Scenes Using Aerial Photos, DEMs, Arc, and ArcScene  

NSDL National Science Digital Library

The first part of this activity teaches students how to make a high quality shaded relief image of an aerial photo using ArcMap, an orthophoto, and a DEM by matching the illumination direction on the hillshade created from the DEM with the illumination direction at the time the photo was taken. In the second part of this activity, students use a digital orthophoto with an associated DEM, and ArcScene to construct a high resolution 3D visual version of the scene that can be tilted, panned, and zoomed in real time, providing an outstanding way for students to visualize landscape. This activity does not come with a data set. Any orthophoto and DEM can be used.

Barb Tewksbury

154

A New Double-band-electrode Channel Flow DEMS Cell: Application for Detecting Product Formation during Methanol Electrooxidation  

SciTech Connect

We present a new double-band-electrode channel flow DEMS (differential electrochemical mass spectrometry) cell and demonstrate its application in mechanistic studies with particular relevance to fuel cells. The cell is composed of two band electrodes, which serve as working and detecting electrodes, respectively, separated by a porous Teflon membrane. The Teflon membrane serves as the interface between the aqueous solution and vacuum, through which gases and volatile species can be transported. The hydrodynamic electrochemical characteristics and mass spectrometric behavior have been characterized. With this DEMS cell, gaseous and volatile electrochemical products formed at the working electrode are monitored by mass spectrometry, while nonvolatile products can be selectively detected at the detecting (downstream) electrode. Thus, this system can be considered as the DEMS analogue of a rotating ring/disk electrode. As test cases, the electrooxidation of formaldehyde and methanol on carbon supported Pt nanoparticle catalysts have been studied using this new channel flow DEMS cell.

Wang, Hongsen; Rus, Eric; Abruña, Héctor D.

2010-01-01

155

TanDEM-X: a TerraSAR-X add-on satellite for single-pass SAR interferometry  

Microsoft Academic Search

TanDEM-X is a mission proposal for a TerraSAR-X add-on satellite for high-resolution single-pass SAR interferometry. This mission proposal has been selected for a Phase A study within the scope of a Call for Proposals for a next German Earth Observation Mission to be launched in 2008\\/2009. The mission has the goal of generating a global Digital Elevation Model (DEM) with

Alberto Moreira; Gerhard Krieger; Irena Hajnsek; David Hounam; Marian Werner; Sebastian Riegger; Eckard Settelmeyer

2004-01-01

156

Open-source MFIX-DEM software for gas–solids flows: Part I—Verification studies  

Microsoft Academic Search

With rapid advancements in computer hardware, it is now possible to perform large simulations of granular flows using the Discrete Element Method (DEM). As a result, solids are increasingly treated in a discrete Lagrangian fashion in the gas–solids flow community. In this paper, the open-source MFIX-DEM software is described that can be used for simulating the gas–solids flow using an

Rahul Garg; Janine Galvin; Tingwen Li; Sreekanth Pannala

2012-01-01

157

On the COSMO-SkyMed Exploitation for Interferometric DEM Generation  

NASA Astrophysics Data System (ADS)

DEM products for Earth observation space-borne applications are being to play a role of increasing importance due to the new generation of high resolution sensors (both optical and SAR). These new sensors demand elevation data for processing and, on the other hand, they provide new possibilities for DEM generation. Till now, for what concerns interferometric DEM, the Shuttle Radar Topography Mission (SRTM) has been the reference product for scientific applications all over the world. SRTM mission [1] had the challenging goal to meet the requirements for a homogeneous and reliable DEM fulfilling the DTED-2 specifications. However, new generation of high resolution sensors (including SAR) pose new requirements for elevation data in terms of vertical precision and spatial resolution. DEM are usually used as ancillary input in different processing steps as for instance geocoding and Differential SAR Interferometry. In this context, the recent SAR missions of DLR (TerraSAR-X and TanDEM-X) and ASI (COSMO-SkyMed) can play a promising role thanks to their high resolution both in space and time. In particular, the present work investigates the potentialities of the COSMO/SkyMed (CSK) constellation for ground elevation measurement with particular attention devoted to the impact of the improved spatial resolution wrt the previous SAR sensors. The recent scientific works, [2] and [3], have shown the advantages of using CSK in the monitoring of terrain deformations caused by landslides, earthquakes, etc. On the other hand, thanks to the high spatial resolution, CSK appears to be very promising in monitoring man-made structures, such as buildings, bridges, railways and highways, thus enabling new potential applications (urban applications, precise DEM, etc.). We present results obtained by processing both SPOTLIGHT and STRIPMAP acquisitions through standard SAR Interferometry as well as multi-pass interferometry [4] with the aim of measuring ground elevation. Acknowledgments Work supported by ASI (Agenzia Spaziale Italiana) in the framework of the project "AO-COSMO Project ID-1462 - Feasibility of possible use of COSMO/SkyMed in bistatic SAR Earth observation - ASI Contract I/063/09/0". References [1] B. Rabus, M. Eineder, A. Roth, and R. Bamler, "The Shuttle Radar Topography Mission-A new class of digital elevation models acquired by spaceborne radar," ISPRS J. Photogramm. Remote Sens., vol. 57, no. 4, pp. 241-262, Feb. 2003. [2] F. BOVENGA, D. O. NITTI, R. NUTRICATO, M. T. CHIARADIA, "C- and X-band multi-pass InSAR analysis over Alpine and Apennine regions". In Proceedings of the European Space Agency Living Planet Symposium, June 28 - July 2, 2010, Bergen, Norway. [3] D. REALE, D. O. NITTI, D. PEDUTO, R. NUTRICATO, F. BOVENGA, G. FORNARO, "Postseismic Deformation Monitoring With The COSMO/SKYMED Constellation". IEEE Geoscience Remote Sensing Letters, 2011. DOI: 10.1109/LGRS.2010.2100364 [4] Nitti, D.O., Nutricato, R., Bovenga, F., Conte, D., Guerriero, L. & Milillo, G., "Quantitative Analysis of Stripmap And Spotlight SAR Interferometry with CosmoSkyMed constellation.", Proceedings if IEEE IGARSS 2009, July 13-17, 2009. Cape Town, South Africa.

Teresa, C. M.; Raffaele, N.; Oscar, N. D.; Fabio, B.

2011-12-01

158

Creating High Quality DEMs of Large Scale Fluvial Environments Using Structure-from-Motion  

NASA Astrophysics Data System (ADS)

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-linear transformation to convert the point clouds to the absolute NZTM coordinate system, with average errors of 0.06 m in the horizontal and 0.11 m in the vertical dimensions. The final point clouds extracted had typical point spacings of 0.25 m, well above the metric resolution of airborne LiDAR. To improve data handling, the final point cloud was decimated to point spacings of 0.5 m using a recently developed gridding procedure (Rychkov, Brasington, & Vericat, 2012), and finally converted into a DEM using a Delaunay constrained TIN in ArcGIS. Results reveal SfM's ability to produce high quality terrain products of large scale fluvial environments that can outperform LiDAR, and can potentially compare with TLS. PhotoScan offers a straightforward method to generate, transform, and export DEMs that requires little user knowledge of photogrammetric processes. Further, the affordability and reduced field work offer low budget researchers the ability to produce repeat surveys for in-depth temporal studies. Funding supported by the New Zealand Department of Conservation.

Javernick, L. A.; Brasington, J.; Caruso, B. S.; Hicks, M.; Davies, T. R.

2012-12-01

159

Coupling photogrammetric data with DFN-DEM model for rock slope hazard assessment  

NASA Astrophysics Data System (ADS)

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 fracture persistency in order to enhance the possible contribution of rock bridges on the failure surface development. It is believed that the proposed methodology can bring valuable complementary information for rock slope stability analysis in presence of complex fractured system for which classical "Factor of Safety" is difficult to express. References • Harthong B., Scholtès L. & F.V. Donzé, Strength characterization of rock masses, using a coupled DEM-DFN model, Geophysical Journal International, doi: 10.1111/j.1365-246X.2012.05642.x, 2012. • Kozicki J & Donzé FV. YADE-OPEN DEM: an open--source software using a discrete element method to simulate granular material, Engineering Computations, 26(7):786-805, 2009 • Kozicki J, Donzé FV. A new open-source software developed for numerical simulations using discrete modeling methods, Comp. Meth. In Appl. Mech. And Eng. 197:4429-4443, 2008. • Poropat, G.V., New methods for mapping the structure of rock masses. In Proceedings, Explo 2001, Hunter Valley, New South Wales, 28-31 October 2001, pp. 253-260, 2001. • Scholtès, L. & Donzé FV. Modelling progressive failure in fractured rock masses using a 3D discrete element method, International Journal of Rock Mechanics and Mining Sciences, 52:18-30, 2012a. • Scholtès, L. & Donzé, F.-V., DEM model for soft and hard rocks: role of grain interlocking on strength, J. Mech. Phys. Solids, doi: 10.1016/j.jmps.2012.10.005, 2012b. • Sirovision, Commonwealth Scientific and Industrial Research Organisation CSIRO, Siro3D Sirovision 3D Imaging Mapping System Manual Version 4.1, 2010

Donze, Frederic; Scholtes, Luc; Bonilla-Sierra, Viviana; Elmouttie, Marc

2013-04-01

160

Dem Bones  

NSDL National Science Digital Library

In this case, students enter the world of a forensic anthropologist who must determine the sex and age of an individual from a collection of bones. Students, in turn, simulate some of the actual procedures conducted in a forensic anthropologist's lab, exa

Alease Bruce

2001-09-01

161

Computer vision: automating DEM generation of active lava flows and domes from photos  

NASA Astrophysics Data System (ADS)

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 Cordón-Caulle, images of the active lava flow were taken on foot from a ridge overlooking the flow. To assess the evolution of the flow front, two DEMs were derived from collections of ~400 images taken on different days. To scale and geo-reference the data, one image sequence was accompanied by simultaneous collection of a GPS track using a consumer handheld GPS unit; no control points were used. The second survey was then scaled and georeferenced to the first, using features identifiable in both image sets, giving an RMS error of ~0.22 m. DEM comparison then allows advance rates and mechanisms to be identified, and comparisons drawn with emplacement processes of basaltic flows. In both case studies, the SfM-MVS approach allowed DEM generation when access or lack of dedicated surveying equipment and expertise prevented standard techniques from being deployed.olima dome 2011: 3D point cloud data

James, M. R.; Varley, N. R.; Tuffen, H.

2012-12-01

162

High mobility of large mass movements: a study by means of FEM/DEM simulations  

NASA Astrophysics Data System (ADS)

Large mass movements, such as rock avalanches and large volcanic debris avalanches are characterized by extremely long propagation, which cannot be modelled using normal sliding friction law. For this reason several studies and theories derived from field observation, physical theories and laboratory experiments, exist to try to explain their high mobility. In order to investigate more into deep some of the processes recalled by these theories, simulations have been run with a new numerical tool called Y-GUI based on the Finite Element-Discrete Element Method FEM/DEM. The FEM/DEM method is a numerical technique developed by Munjiza et al. (1995) where Discrete Element Method (DEM) algorithms are used to model the interaction between different solids, while Finite Element Method (FEM) principles are used to analyze their deformability being also able to explicitly simulate material sudden loss of cohesion (i.e. brittle failure). In particular numerical tests have been run, inspired by the small-scale experiments done by Manzella and Labiouse (2013). They consist of rectangular blocks released on a slope; each block is a rectangular discrete element made of a mesh of finite elements enabled to fragment. These simulations have highlighted the influence on the propagation of block packing, i.e. whether the elements are piled into geometrical ordinate structure before failure or they are chaotically disposed as a loose material, and of the topography, i.e. whether the slope break is smooth and regular or not. In addition the effect of fracturing, i.e. fragmentation, on the total runout have been studied and highlighted.

Manzella, I.; Lisjak, A.; Grasselli, G.

2013-12-01

163

Multi-frequency study of DEM L299 in the Large Magellanic Cloud  

NASA Astrophysics Data System (ADS)

Aims: We have studied the H ii region DEM L299 in the Large Magellanic Cloud (LMC) to understand its physical characteristics and morphology in different wavelengths. Methods: 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?, [S ii], and [O iii] data from the Magellanic Cloud Emission Line Survey (MCELS) and radio 21 cm line data from the Australia Telescope Compact Array (ATCA) and the Parkes Telescope as well as radio continuum data (3 cm, 6 cm, 20 cm, 36 cm) from ATCA and from the Molonglo Synthesis Telescope (MOST). Results: 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 [S ii]/H? 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 a shell around both objects. Radio continuum data show diffuse emission at the position of DEM L299, which appears clearly distinguished from the H ii region LHA 120-N 164 that lies south-west of it. We determined the spectral index of SNR B0543-68.9 to be ? = -0.34, which indicates the dominance of thermal emission and therefore a rather mature remnant. We determined the basic properties of the diffuse X-ray emission for the SNR, the superbubble, and a possible blowout region of the bubble, as suggested by the optical and X-ray data. We obtained an age of (8.9+9.2-5.4) kyr for the SNR and a temperature of (0.64+0.73-0.20) keV for the hot gas inside the SNR, as well as a thermal energy content and temperature of the hot gas inside the superbubble of (4.3+8.1-2.6) × 1050 ?0.5 erg and (0.74+0.36-0.30) keV, with ? being the gas-filling factor. Conclusions: We conclude that DEM L299 consists of a superposition of SNR B0543-68.9 and a superbubble, which we identified based on optical data. Based on observations obtained with XMM-Newton, an ESA science mission with instruments and contributions directly funded by ESA member states and NASA.

Warth, Gabriele; Sasaki, Manami; Kavanagh, Patrick J.; Filipovi?, Miroslav D.; Points, Sean D.; Bozzetto, Luke M.

2014-07-01

164

The research by topographic correction methods of airborne hyperspectral remote sensing data based on DEM  

NASA Astrophysics Data System (ADS)

High spectral resolution is the main characteristic of hyperspectral remote sensing. The image of objects includes various information of space, radiation and spectral information, and we can also construct a continuous spectrum curve in the imaging range. The purpose of topographic correction is to eliminate the effects of solar light , which may make the spectral curve not accurate compared with the practical curve, on radiation values of irregular ground object. This paper is to analysis the advantages and disadvantages of various topographic correction methods, and provide accurate experimental data for quantitative remote sensing, which based on the area of airborne hyperspectral remote sensing image and DEM, comparing with the measured spectral curve.

Liu, Chunfeng; Li, Na; Li, Xudong; Zhao, Huijie

2014-12-01

165

DEM L241, A SUPERNOVA REMNANT CONTAINING A HIGH-MASS X-RAY BINARY  

SciTech Connect

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}.

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

166

A 3D DEM-LBM approach for the assessment of the quick condition for sands  

NASA Astrophysics Data System (ADS)

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).

Mansouri, M.; Delenne, J.-Y.; El Youssoufi, M. S.; Seridi, A.

2009-09-01

167

Comparison of elevation derived from insar data with dem from topography map in Son Dong, Bac Giang, Viet Nam  

NASA Astrophysics Data System (ADS)

Digital Elevation Models (DEMs) are used in many applications in the context of earth sciences such as in topographic mapping, environmental modeling, rainfall-runoff studies, landslide hazard zonation, seismic source modeling, etc. During the last years multitude of scientific applications of Synthetic Aperture Radar Interferometry (InSAR) techniques have evolved. It has been shown that InSAR is an established technique of generating high quality DEMs from space borne and airborne data, and that it has advantages over other methods for the generation of large area DEM. However, the processing of InSAR data is still a challenging task. This paper describes InSAR operational steps and processing chain for DEM generation from Single Look Complex (SLC) SAR data and compare a satellite SAR estimate of surface elevation with a digital elevation model (DEM) from Topography map. The operational steps are performed in three major stages: Data Search, Data Processing, and product Validation. The Data processing stage is further divided into five steps of Data Pre-Processing, Co-registration, Interferogram generation, Phase unwrapping, and Geocoding. The Data processing steps have been tested with ERS 1/2 data using Delft Object-oriented Interferometric (DORIS) InSAR processing software. Results of the outcome of the application of the described processing steps to real data set are presented.

Nguyen, Duy

2012-07-01

168

Kinematic behaviour of a large earthflow defined by surface displacement monitoring, DEM differencing, and ERT imaging  

NASA Astrophysics Data System (ADS)

Large earthflow-type landslides are destructive mass movement phenomena with highly unpredictable behaviour. Knowledge of earthflow kinematics is essential for understanding the mechanisms that control its movements. The present paper characterises the kinematic behaviour of a large earthflow near the village of ?ubietová in Central Slovakia over a period of 35 years following its most recent reactivation in 1977. For this purpose, multi-temporal spatial data acquired by point-based in-situ monitoring and optical remote sensing methods have been used. Quantitative data analyses including strain modelling and DEM differencing techniques have enabled us to: (i) calculate the annual landslide movement rates; (ii) detect the trend of surface displacements; (iii) characterise spatial variability of movement rates; (iv) measure changes in the surface topography on a decadal scale; and (v) define areas with distinct kinematic behaviour. The results also integrate the qualitative characteristics of surface topography, in particular the distribution of surface structures as defined by a high-resolution DEM, and the landslide subsurface structure, as revealed by 2D resistivity imaging. Then, the ground surface kinematics of the landslide is evaluated with respect to the specific conditions encountered in the study area including slope morphology, landslide subsurface structure, and local geological and hydrometeorological conditions. Finally, the broader implications of the presented research are discussed with particular focus on the role that strain-related structures play in landslide kinematic behaviour.

Prokešová, Roberta; Kardoš, Miroslav; Tábo?ík, Petr; Medve?ová, Alžbeta; Stacke, Václav; Chudý, František

2014-11-01

169

DEM modeling of failure mechanisms induced by excavations on the Moon  

NASA Astrophysics Data System (ADS)

2D Discrete Element Method (DEM) analyses were performed for excavations supported by retaining walls in lunar environment. The lunar terrain is made of a layer of sand (regolith) which differs from terrestrial sands for two main features: the presence of adhesive attractive forces due to van der Waals interactions and grains being very irregular in shape leading to high interlocking. A simplified contact model based on linear elasticity and perfect plasticity was employed. The contact model includes a moment - relative rotation law to account for high interlocking among grains and a normal adhesion law to account for the van der Waals interactions. Analyses of the excavations were run under both lunar and terrestrial environments. Under lunar environment, gravity is approximately one sixth than the value on Earth and adhesion forces between grains of lunar regolith due to van der Waals interactions are not negligible. From the DEM simulations it emerged that van der Waals interactions may significantly increase the bending moment and deflection of the retaining wall, and the ground displacements. Hence this study indicates that an unsafe estimate of the wall response to an excavation on the Moon would be obtained from physical experiments performed in a terrestrial environment, i.e., considering the effect of gravity but neglecting the van der Waals interactions.

jiang, mingjing; shen, zhifu; Utili, Stefano

2013-04-01

170

Assessment of an ASTER-generated DEM for 2D hydrodynamic flood modeling  

NASA Astrophysics Data System (ADS)

Flood modeling often provides inputs to flood hazard management. In the present work we studied the flooding characteristics in the data scarce region of the Lake Tana basin at the source of the Blue Nile River. The study required to integrate remote sensing, GIS with a two-dimensional (2D) module of the SOBEK flood model. The resolution of the topographic data in many areas, such as the Lake Tana region, is commonly too poor to support detailed 2D hydrodynamic modeling. To overcome such limitations, we used a Digital Elevation Model (DEM) which was generated from the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) image. A GIS procedure is developed to reconstruct the river terrain and channel bathymetry. The results revealed that a representation of the river terrain largely affects the simulated flood characteristics. Simulations indicate that effects of Lake Tana water levels propagate up to 13 km along the Ribb River. We conclude that a 15 m resolution ASTER DEM can serve as an input to detailed 2D hydrodynamic modeling in data scarce regions. However, for this purpose it is necessary to accurately reconstruct the river terrain geometry and flood plain topography based on ground observations by means of a river terrain model.

Tarekegn, Tesfaye Haimanot; Haile, Alemseged Tamiru; Rientjes, Tom; Reggiani, P.; Alkema, Dinand

2010-12-01

171

Open-source MFIX-DEM software for gas-solids flows: Part II Validation studies  

SciTech Connect

With rapid advancements in computer hardware and numerical algorithms, computational fluid dynamics (CFD) has been increasingly employed as a useful tool for investigating the complex hydrodynamics inherent in multiphase flows. An important step during the development of a CFD model and prior to its application is conducting careful and comprehensive verification and validation studies. Accordingly, efforts to verify and validate the open-source MFIX-DEM software, which can be used for simulating the gas solids flow using an Eulerian reference frame for the continuum fluid and a Lagrangian discrete framework (Discrete Element Method) for the particles, have been made at the National Energy Technology Laboratory (NETL). In part I of this paper, extensive verification studies were presented and in this part, detailed validation studies of MFIX-DEM are presented. A series of test cases covering a range of gas solids flow applications were conducted. In particular the numerical results for the random packing of a binary particle mixture, the repose angle of a sandpile formed during a side charge process, velocity, granular temperature, and voidage profiles from a bounded granular shear flow, lateral voidage and velocity profiles from a monodisperse bubbling fluidized bed, lateral velocity profiles from a spouted bed, and the dynamics of segregation of a binary mixture in a bubbling bed were compared with available experimental data, and in some instances with empirical correlations. In addition, sensitivity studies were conducted for various parameters to quantify the error in the numerical simulation.

Li, Tingwen [National Energy Technology Laboratory (NETL); Garg, Rahul [National Energy Technology Laboratory (NETL); Galvin, Janine [National Energy Technology Laboratory (NETL); Pannala, Sreekanth [ORNL

2012-01-01

172

Open-Source MFIX-DEM Software for Gas-Solids Flows: Part II - Validation Studies  

SciTech Connect

With rapid advancements in computer hardware and numerical algorithms, computational fluid dynamics (CFD) has been increasingly employed as a useful tool for investigating the complex hydrodynamics inherent in multiphase flows. An important step during the development of a CFD model and prior to its application is conducting careful and comprehensive verification and validation studies. Accordingly, efforts to verify and validate the open-source MFIX-DEM software, which can be used for simulating the gas–solids flow using an Eulerian reference frame for the continuum fluid and a Lagrangian discrete framework (Discrete Element Method) for the particles, have been made at the National Energy Technology Laboratory (NETL). In part I of this paper, extensive verification studies were presented and in this part, detailed validation studies of MFIX-DEM are presented. A series of test cases covering a range of gas–solids flow applications were conducted. In particular the numerical results for the random packing of a binary particle mixture, the repose angle of a sandpile formed during a side charge process, velocity, granular temperature, and voidage profiles from a bounded granular shear flow, lateral voidage and velocity profiles from a monodisperse bubbling fluidized bed, lateral velocity profiles from a spouted bed, and the dynamics of segregation of a binary mixture in a bubbling bed were compared with available experimental data, and in some instances with empirical correlations. In addition, sensitivity studies were conducted for various parameters to quantify the error in the numerical simulation.

Li, Tingwen

2012-04-01

173

Assessing volume change of tropical Peruvian glaciers from multi-temporal digital elevation models (DEMs)  

NASA Astrophysics Data System (ADS)

Although far smaller than large polar ice caps, mountain glaciers are significant contributors to sea level rise and tropical glaciers in particular are sources of critical water resources to regional societies. The glaciers in Cordillera Blanca, the Andes of Peru, hold important environmental and economic concerns of regional water supplies to communities in the arid western part of the country under continued global climate change. Yet steep relief and remote locations present challenges for measuring mass changes in tropical glaciers. Remotely sensed images provide feasible opportunities to measure glacier surface area changes. We use a combination of satellite and airborne remote sensing, digital photogrammetry and geospatial techniques to assess the surface area, volume and topographic changes of key glaciers in the Cordillera Blanca, Peru between 1962 and 2008. The intercomparison of digital elevation models (DEMs) from airborne Light Detection and Range (LiDAR) data of 2008, multispectral Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) of 2001-2008 and stereo-paired airborne photographs of 1962 for deriving elevation differences over time reveal the data quality to measure the volume loss in the area. The DEMs over non-glacier areas in the study sites were selected and differentially corrected Global Positioning System (dGPS) data points were used for comparison as well. The motivation of this study is to refine a surface area to volume scaling for tropical glaciers to enable extrapolation of more detailed inventory of glacier volume and water resources.

Huh, K.; Mark, B. G.

2012-12-01

174

Investigating sediment budgets and pathways using LiDAR DEMs of difference and a geomorphological map  

NASA Astrophysics Data System (ADS)

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.

Hilger, Ludwig; Becht, Michael; Heckmann, Tobias

2014-05-01

175

Micro relief parameters from high resolution DEMs as representative values for physical based soil erosion models  

NASA Astrophysics Data System (ADS)

Field parameters, such as hydraulic roughness are indispensable for modeling soil erosion on a physical base. Established approaches to acquire parameters for hydraulic roughness are based on flow velocity, flow volume and the slope angle. Other methods refer to grain sizes affecting a volume flow as an indicator for roughness. This work presents a remote sensing approach to generate high resolution surface reconstructions of rough terrain in different scales. As the ability of producing high resolution digital elevation models (DEM) is rapidly increasing over the last years, the possibilities of morphometric analysis of micro reliefs are also constantly developing. Point spacings of very dense point clouds acquired with the help of terrestrial laserscanning or structure from motion are minimal. Thus, even small grain sizes and inhomogeneity can be identified in the DEMs. Surface models used for this study were acquired in advance and afterwards simulated flow and rainfall events. Resulting changes in surface roughness caused by fluvial erosion could be detected on bare soil and sparsely vegetated areas. To validate the measured roughness values flow velocities and flow volumes were regularly recorded during the events. This work aims to present a step forward to standardizing new methods in data acquisition in soil erosion modeling.

Neugirg, Fabian; Kaiser, Andreas; Haas, Florian; Veh, Georg; Schindewolf, Marcus; Schmidt, Jürgen; Becht, Michael

2014-05-01

176

DEM generation from digital photographs using computer vision: Accuracy and application  

NASA Astrophysics Data System (ADS)

Data for detailed digital elevation models (DEMs) are usually collected by expensive laser-based techniques, or by photogrammetric methods that require expertise and specialist software. However, recent advances in computer vision research now permit 3D models to be automatically derived from unordered collections of photographs, and offer the potential for significantly cheaper and quicker DEM production. Here, we review the advantages and limitations of this approach and, using imagery of the summit craters of Piton de la Fournaise, compare the precisions obtained with those from formal close range photogrammetry. The surface reconstruction process is based on a combination of structure-from-motion and multi-view stereo algorithms (SfM-MVS). Using multiple photographs of a scene taken from different positions with a consumer-grade camera, dense point clouds (millions of points) can be derived. Processing is carried out by automated 'reconstruction pipeline' software downloadable from the internet. Unlike traditional photogrammetric approaches, the initial reconstruction process does not require the identification of any control points or initial camera calibration and is carried out with little or no operator intervention. However, such reconstructions are initially un-scaled and un-oriented so additional software has been developed to permit georeferencing. Although this step requires the presence of some control points or features within the scene, it does not have the relatively strict image acquisition and control requirements of traditional photogrammetry. For accuracy, and to allow error analysis, georeferencing observations are made within the image set, rather than requiring feature matching within the point cloud. Application of SfM-MVS is demonstrated using images taken from a microlight aircraft over the summit of Piton de la Fournaise volcano (courtesy of B. van Wyk de Vries). 133 images, collected with a Canon EOS D60 and 20 mm fixed focus lens, were used to create a ~1.6 km wide DEM covering the summit craters. When compared with a DEM constructed using close-range photogrammetry the SfM-MVS results showed an RMS error of 1.0 m. The overall precision of the project can be considered by ratioing this against the average viewing distance (1000 m). This relative precision of 1:1000 is in line with the results of other projects carried out over a range of spatial scales (down to ~0.1 m), so appears to be a characteristic expected achievable precision for the SfM-MVS approach. Consequently, over shorter viewing distances, absolute precisions increase - e.g. centimeter-level precisions for outcrop-scale studies where viewing distances may be expected to be of order 10 m. Although SfM-MVS cannot deliver the accuracy and precision of formal close-range photogrammetry, it can approach the results that are achievable from single stereo image pairs. However, the main advantages of the technique lie in the enhanced flexibility in image collection and automated processing, both of which significantly decrease the level of expertise required. When compared with terrestrial laser scanning at outcrop scales, the data collection time in the field can be reduced by ~80%. SfM-MVS data quality is sufficient for the technique to provide valuable DEMs of active flows and domes where access to (or for) modern surveying equipment is restricted.

James, M. R.; Robson, S.

2012-12-01

177

BOREAS HYD-8 DEM Data Over the NSA-MSA and SSA-MSA in the UTM Projection  

NASA Technical Reports Server (NTRS)

The BOREAS HYD-8 team focused on describing the scaling behavior of water and carbon flux processes at local and regional scales. These DEMs were produced from digitized contours at a cell resolution of 100 meters. Vector contours of the area were used as input to a software package that interpolates between contours to create a DEM representing the terrain surface. The vector contours had a contour interval of 25 feet. The data cover the BOREAS MSAs of the SSA and NSA and are given in a UTM map projection. Most of the elevation data from which the DEM was produced were collected in the 1970s or 1980s. The data are stored in binary, image format files. The data files are available on a CD-ROM (see document number 20010000884) or from the Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC).

Wang, Xue-Wen; Hall, Forrest G. (Editor); Knapp, David E. (Editor); Band, L. E.; Smith, David E. (Technical Monitor)

2000-01-01

178

Calibration and validation of DEM rolling and sliding friction coefficients in angle of repose and shear measurements  

NASA Astrophysics Data System (ADS)

Pile formation and rotating drum experiments followed by DEM simulations using glass beads (1.5 and 3.0 mm diameter) and polyamide spheres (3.0 mm diameter) were conducted. A wide range of rotation velocities was tested (from 1 to 90 rpm), the drum fill degree was set to 50%. The material inclination angles obtained in pile formation experiments were comparable with low speed rotating drum tests. The experimentally obtained results were used to determine DEM friction coefficients. Both, good qualitative and good quantitative agreements between experiments and simulations were found for rotation speeds up to 5 rpm, whereas for higher rotation speeds small discrepancies were observed.

Frankowski, Piotr; Morgeneyer, Martin

2013-06-01

179

Volcanic Landform Classification of Iwate Volcano from DEM-Derived Thematic Maps  

NASA Astrophysics Data System (ADS)

Over the last three decades, digital elevation models (DEMs) have been developed as surface data instead of contour lines to allow numerical analysis or modeling of terrain by computer. DEMs have allowed the development of algorithms to rapidly derive slope, relief, convexity, concavity and aspect of any points of surface, and also have allowed the definition of a number of new morphometric measures i.e. openness (Yokoyama et al., 2002). Openness is an angular measure of the relation between surface relief and horizontal distance. Openness has two viewer perspectives. Positive values, expressing openness above the surface, are high for convex forms, whereas negative values describe this attribute below the surface and are high for concave forms. The emphasis of terrain convexity and concavity in openness maps facilitates the interpretation of landforms on the Earth_fs surface. Prima et al. (2003) proposed automated landform classification using openness and slope with genetic factors. This method had been proved to produce good classification for constructional (alluvial plains, alluvial fans and volcanoes) and erosional (hills and mountains) landforms. The capability of this method to classify landforms from DEMs with genetic factors is important because it allows landform evolution to be numerically analyzed. In this study, we adopted this method to classify volcanic landforms of Iwate Volcano from Honshu, Japan, where volcanic landforms were categorized referring to geological map of Iwate Volcano (Doi, 2000). This process took three steps. First, the characteristic of each category was evaluated against the mean and standard deviation of slope, and both positive and negative openness, in two dimensional feature spaces. Second, the characteristic of each category were observed and the combinations of mean and standard deviation of slope and openness showing high separabilities were selected. We found that the standard deviation of slope, positive and negative openness yielded high separabilities of each category and indicated consistency between the trend of categories_f distribution and their geological successions. Third, Mahalanobis distance was used as classification rule to automatically classify the volcanic landforms of Iwate Volcano with those categories. The result shows fine interpretation of volcanic landforms of Iwate Volcano according to their geological successions. The northeastern sector of Iwate Volcano that has relatively young strata was clearly identified against other sectors of the volcano. Although some misclassification occurred in places where the ages of landform formation are relatively close, we considered that the present result is provisionally acceptable because the classified landforms in major accurately replicated many components of volcanic landforms of Iwate Volcano.

Prima, A. O.; Yoshida, T.

2004-12-01

180

Turbidity Current Transport using DEM and FEM: a Hybrid Lagrangian-Eulerian Approach  

NASA Astrophysics Data System (ADS)

In this work we describe a contribution to the study of turbidity transport in scales smaller than TFM (two-fluid models), The intent of the work, part of a large scale simulation project, is to assess local, small scale parameters and their upscaling. The hybrid model is based on a Lagrangian-Eulerian approach under a class of the so called Unresolved Discrete Particle Method (UDPM). In this 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 finite element method (FEM), Fluid motion is governed by Navier-Stokes equations which are solved by an appropriate FEM implementation. Closure equation are used to compute drag and lift forces over the particles in the DEM framework. Volume averaged momentum sink terms are included in the fluid equations. The resulting coupled DEM-FEM model is integrated in time with a subcycling scheme. The aforementioned scheme was applied in the simulation of a sedimentation basin as depicted in figures 1 and 2 to investigate flow and deposition features of the suspension in a finer scale. For this purpose a submodel of the basin was generated. Mapping variables back and forth the Eulerian (finite element) model and the Lagrangian (discrete element) model were performed during the subcycled integration of the hybrid model. References: [1] Hoomans, B.P.B., Kuipers, J.A.M., Swaaij, van W.P.M," Granular dynamics Simulation of segregation phenomena in bubbling gas-fluidised beds", Powder Technology, V 109, Issues 1-3, 3 April 2000, pp 41-48; [2] Cho, S.H., Choi,H.G, Yoo, J.Y.,"Direct numerical simulation of fluid flow laden with many particles", International Journal of Multiphase Flow, V 31, Issue 4, April 2005, pp 435-451;; Sedimentation basin: sectioning the turbidity plume in the Eulerian FE model for setting up the discrete particle model. ; Sedimentation Basin: section of the turbidity plume displaying the generated discrete particle model underneath.

Alves, J. L.; Guevara, N. O., Jr.; Silva, C. E.; Alves, F. T.; Gazoni, L. C.; Coutinho, A.; Camata, J.; Elias, R. N.; Paraizo, P.

2013-05-01

181

Semi-automated extraction of landslides in Taiwan based on SPOT imagery and DEMs  

NASA Astrophysics Data System (ADS)

The vast availability and improved quality of optical satellite data and digital elevation models (DEMs), as well as the need for complete and up-to-date landslide inventories at various spatial scales have fostered the development of semi-automated landslide recognition systems. Among the tested approaches for designing such systems, object-based image analysis (OBIA) stepped out to be a highly promising methodology. OBIA offers a flexible, spatially enabled framework for effective landslide mapping. Most object-based landslide mapping systems, however, have been tailored to specific, mainly small-scale study areas or even to single landslides only. Even though reported mapping accuracies tend to be higher than for pixel-based approaches, accuracy values are still relatively low and depend on the particular study. There is still room to improve the applicability and objectivity of object-based landslide mapping systems. The presented study aims at developing a knowledge-based landslide mapping system implemented in an OBIA environment, i.e. Trimble eCognition. In comparison to previous knowledge-based approaches, the classification of segmentation-derived multi-scale image objects relies on digital landslide signatures. These signatures hold the common operational knowledge on digital landslide mapping, as reported by 25 Taiwanese landslide experts during personal semi-structured interviews. Specifically, the signatures include information on commonly used data layers, spectral and spatial features, and feature thresholds. The signatures guide the selection and implementation of mapping rules that were finally encoded in Cognition Network Language (CNL). Multi-scale image segmentation is optimized by using the improved Estimation of Scale Parameter (ESP) tool. The approach described above is developed and tested for mapping landslides in a sub-region of the Baichi catchment in Northern Taiwan based on SPOT imagery and a high-resolution DEM. An object-based accuracy assessment is conducted by quantitatively comparing extracted landslide objects with landslide polygons that were visually interpreted by local experts. The applicability and transferability of the mapping system are evaluated by comparing initial accuracies with those achieved for the following two tests: first, usage of a SPOT image from the same year, but for a different area within the Baichi catchment; second, usage of SPOT images from multiple years for the same region. The integration of the common knowledge via digital landslide signatures is new in object-based landslide studies. In combination with strategies to optimize image segmentation this may lead to a more objective, transferable and stable knowledge-based system for the mapping of landslides from optical satellite data and DEMs.

Eisank, Clemens; Hölbling, Daniel; Friedl, Barbara; Chen, Yi-Chin; Chang, Kang-Tsung

2014-05-01

182

A New Processing Chain based on Neural Networks for the Construction of X-SAR DEM: Tuning of new algorithms and Validation of the Output  

NASA Astrophysics Data System (ADS)

The main goal of the activity we plan to perform concerns the description of a new approach for the production of Digital Elevation Models (DEM) based on neural network and the relative activity of their validation. The DEM have been extracted from the X-SAR images caught by the COSMO-SKYMED Italian space mission fully devoted to remote sensing. In particular we have developed in parallel two processing chain to obtain DEMs. The first one applies the conventional algorithms currently used and implemented in the DORIS open source software developed by Delft University. The second one implements our algorithms which apply neural networks to determine the features of the single pixels taking into account also the behavior of neighboring pixels. Thus a comparison of the achieved DEM with the two different processing chain is performed. For the validation of DEMs obtained with our algorithms we plan to construct a third DEM overlapped to the other two, using the GPS-RTK technique. This technique is capable to return DEMs with a precision of few tens of centimeters; i.e. enough precise to validate the X-SAR DEM. For the validation activity we have selected an area close to Matera Space Geodesy Center which cover both flat an hilly surfaces.

Brizio, Franco; Gentili, Mario; Fabrizi, Marco; Vespe, Francesco; Benedetto, Catia

2013-04-01

183

Augusta Ada Byron, Countess of Lovelace Ada Byron wird als Tochter von Anna Byron und dem Dichter Lord Byron 1815 in England  

E-print Network

Augusta Ada Byron, Countess of Lovelace Ada Byron wird als Tochter von Anna Byron und dem Dichter¨uckkehrt, lernt Ada ihn nie kennen. Sie verbringt ihre Kindheit bei ihrer zur¨uckgezogen lebenden Mutter. Diese k¨ummert sich auch um Adas Erziehung. Anna Byron hatte selbst Algebra, Geometrie und Astronomie bei dem

Pientka, Brigitte

184

Mechanistic Based DEM Simulation of Particle Attrition in a Jet Cup  

SciTech Connect

The attrition of particles is a major industrial concern in many fluidization systems as it can have undesired effects on the product quality and on the reliable operation of process equipment. Therefore, to accomodate the screening and selection of catalysts for a specific process in fluidized beds, risers, or cyclone applications, their attrition propensity is usually estimated through jet cup attrition testing, where the test material is subjected to high gas velocities in a jet cup. However, this method is far from perfect despite its popularity, largely due to its inconsistency in different testing set-ups. In order to better understand the jet cup testing results as well as their sensitivity to different operating conditions, a coupled computational fluid dynamic (CFD) - discrete element method (DEM) model has been developed in the current study to investigate the particle attrition in a jet cup and its dependence on various factors, e.g. jet velocity, initial particle size, particle density, and apparatus geometry.

Xu, Wei; DeCroix, David; Sun, Xin

2014-02-01

185

Revealing topographic lineaments through IHS enhancement of DEM data. [Digital Elevation Model  

NASA Technical Reports Server (NTRS)

Intensity-hue-saturation (IHS) processing of slope (dip), aspect (dip direction), and elevation to reveal subtle topographic lineaments which may not be obvious in the unprocessed data are used to enhance digital elevation model (DEM) data from northwestern Nevada. This IHS method of lineament identification was applied to a mosiac of 12 square degrees using a Cray Y-MP8/864. Square arrays from 3 x 3 to 31 x 31 points were tested as well as several different slope enhancements. When relatively few points are used to fit the plane, lineaments of various lengths are observed and a mechanism for lineament classification is described. An area encompassing the gold deposits of the Carlin trend and including the Rain in the southeast to Midas in the northwest is investigated in greater detail. The orientation and density of lineaments may be determined on the gently sloping pediment surface as well as in the more steeply sloping ranges.

Murdock, Gary

1990-01-01

186

Open-source MFIX-DEM software for gas-solids flows: Part I verification studies  

SciTech Connect

With rapid advancements in computer hardware, it is now possible to perform large simulations of granular flows using the Discrete Element Method (DEM). As a result, solids are increasingly treated in a discrete Lagrangian fashion in the gas solids flow community. In this paper, the open-source MFIX-DEM software is described that can be used for simulating the gas solids flow using an Eulerian reference frame for the continuum fluid and a Lagrangian discrete framework (Discrete Element Method) for the particles. This method is referred to as the continuum discrete method (CDM) to clearly make a distinction between the ambiguity of using a Lagrangian or Eulerian reference for either continuum or discrete formulations. This freely available CDM code for gas solids flows can accelerate the research in computational gas solids flows and establish a baseline that can lead to better closures for the continuum modeling (or traditionally referred to as two fluid model) of gas solids flows. In this paper, a series of verification cases is employed which tests the different aspects of the code in a systematic fashion by exploring specific physics in gas solids flows before exercising the fully coupled solution on simple canonical problems. It is critical to have an extensively verified code as the physics is complex with highly-nonlinear coupling, and it is difficult to ascertain the accuracy of the results without rigorous verification. These series of verification tests set the stage not only for rigorous validation studies (performed in part II of this paper) but also serve as a procedure for testing any new developments that couple continuum and discrete formulations for gas solids flows.

Garg, Rahul [National Energy Technology Laboratory (NETL); Galvin, Janine [National Energy Technology Laboratory (NETL); Li, Tingwen [National Energy Technology Laboratory (NETL); Pannala, Sreekanth [ORNL

2012-01-01

187

Open-source MFIX-DEM software for gas-solids flows: Part 1 - Verification studies  

SciTech Connect

With rapid advancements in computer hardware, it is now possible to perform large simulations of granular flows using the Discrete Element Method (DEM). As a result, solids are increasingly treated in a discrete Lagrangian fashion in the gas–solids flow community. In this paper, the open-source MFIX-DEM software is described that can be used for simulating the gas–solids flow using an Eulerian reference frame for the continuum fluid and a Lagrangian discrete framework (Discrete Element Method) for the particles. This method is referred to as the continuum discrete method (CDM) to clearly make a distinction between the ambiguity of using a Lagrangian or Eulerian reference for either continuum or discrete formulations. This freely available CDM code for gas–solids flows can accelerate the research in computational gas–solids flows and establish a baseline that can lead to better closures for the continuum modeling (or traditionally referred to as two fluid model) of gas–solids flows. In this paper, a series of verification cases is employed which tests the different aspects of the code in a systematic fashion by exploring specific physics in gas–solids flows before exercising the fully coupled solution on simple canonical problems. It is critical to have an extensively verified code as the physics is complex with highly-nonlinear coupling, and it is difficult to ascertain the accuracy of the results without rigorous verification. These series of verification tests set the stage not only for rigorous validation studies (performed in part II of this paper) but also serve as a procedure for testing any new developments that couple continuum and discrete formulations for gas–solids flows.

Garg, Rahul; Galvin, Janine; Li, Tingwen; Pannala, Sreekanth

2012-04-01

188

Open Source MFIX-DEM Software for Gas-Solids Flows: Part 1 - Verification Studies  

SciTech Connect

With rapid advancements in computer hardware, it is now possible to perform large simulations of granular flows using the Discrete Element Method (DEM). As a result, solids are increasingly treated in a discrete Lagrangian fashion in the gas–solids flow community. In this paper, the open-source MFIX-DEM software is described that can be used for simulating the gas–solids flow using an Eulerian reference frame for the continuum fluid and a Lagrangian discrete framework (Discrete Element Method) for the particles. This method is referred to as the continuum discrete method (CDM) to clearly make a distinction between the ambiguity of using a Lagrangian or Eulerian reference for either continuum or discrete formulations. This freely available CDM code for gas–solids flows can accelerate the research in computational gas–solids flows and establish a baseline that can lead to better closures for the continuum modeling (or traditionally referred to as two fluid model) of gas–solids flows. In this paper, a series of verification cases is employed which tests the different aspects of the code in a systematic fashion by exploring specific physics in gas–solids flows before exercising the fully coupled solution on simple canonical problems. It is critical to have an extensively verified code as the physics is complex with highly-nonlinear coupling, and it is difficult to ascertain the accuracy of the results without rigorous verification. These series of verification tests set the stage not only for rigorous validation studies (performed in part II of this paper) but also serve as a procedure for testing any new developments that couple continuum and discrete formulations for gas–solids flows.

Garg, Rahul; Galvin, Janine; Li, Tingwen; Pannala, Sreekanth

2012-04-01

189

A Progressive Black Top Hat Transformation Algorithm for Estimating Valley Volumes from DEM Data  

NASA Astrophysics Data System (ADS)

The amount of valley incision and valley volume are important parameters in geomorphology and hydrology research, because they are related to the amount erosion (and thus the volume of sediments) and the amount of water needed to create the valley. This is not only the case for terrestrial research but also for planetary research as such figuring out how much water was on Mars. With readily available digital elevation model (DEM) data, the Black Top Hat (BTH) transformation, an image processing technique for extracting dark features on a variable background, has been applied to DEM data to extract valley depth and estimate valley volume. However, previous studies typically use one single structuring element size for extracting the valley feature and one single threshold value for removing noise, resulting in some finer features such as tributaries not being extracted and underestimation of valley volume. Inspired by similar algorithms used in LiDAR data analysis to separate above ground features and bare earth topography, here we propose a progressive BTH (PBTH) transformation algorithm, where the structuring elements size is progressively increased to extract valleys of different orders. In addition, a slope based threshold was introduced to automatically adjust the threshold values for structuring elements with different sizes. Connectivity and shape parameters of the masked regions were used to keep the long linear valleys while removing other smaller non-connected regions. Preliminary application of the PBTH to Grand Canyon and two sites on Mars has produced promising results. More testing and fine-tuning is in progress. The ultimate goal of the project is to apply the algorithm to estimate the volume of valley networks on Mars and the volume of water needed to form the valleys we observe today and thus infer the nature of the hydrologic cycle on early Mars. The project is funded by NASA's Mars Data Analysis program.

Luo, W.; Pingel, T.; Heo, J.; Howard, A. D.

2013-12-01

190

Micromechanical modelling of monotonic drained and undrained shear behaviour of granular media using three-dimensional DEM  

NASA Astrophysics Data System (ADS)

In this paper, numerical simulation results of isotropic compression and triaxial static shear tests under drained and undrained stress paths on polydisperse assembly of loose and dense spheres are presented. An examination of the micromechanical behaviour of loose and dense assemblies under drained and undrained conditions, considering the particulate nature of granular materials, has been carried out to explain micromechanically the granular material behaviour at the grain scale level. The numerical simulations have been carried out using a discrete element model (DEM) which considers a 1000 sphere particle polydisperse assembly with periodic space representing an infinite three-dimensional space. In this paper, we present how DEM simulations can contribute to developments in constitutive modelling of granular materials through micromechanical approach using information on microstructure evolution. A series of numerical tests are performed using DEM on 3-D assemblages of spheres to study the evolution of the internal variables such as average co-ordination number and induced anisotropy during deformation along with the macroscopic behaviour of the assemblage in drained and undrained shear tests. In a qualitative sense, the macroscopic stress-strain results and stress path evolution in these simulations using 3-D assemblies demonstrate that DEM simulations are capable of reproducing realistic compression and shear behaviour of granular materials.

Sitharam, Thallak. G.; Dinesh, S. V.; Shimizu, N.

2002-10-01

191

Real Time 3D Visualization of DEM Combined with a Robust DCT Based Data-Hiding Method  

E-print Network

Real Time 3D Visualization of DEM Combined with a Robust DCT Based Data-Hiding Method A. Martina, G a technique for color data hiding of images, based on DC components of the DCT-coefficients. In our. The current paper presents a technique for color data hiding of images,4 based on DC components of the DCT

Paris-Sud XI, Université de

192

Atmosphere sounding by GPS radio occultation: First results from TanDEM-X and comparison with TerraSAR-X  

NASA Astrophysics Data System (ADS)

On 21 June 2010 the TerraSAR-X satellite was joined by the TanDEM-X satellite. A Global Positioning System (GPS) radio occultation (RO) experiment using the twin satellites has been carried out to estimate the precision of GPS atmospheric soundings. For the Day Of Year (DOY) 330-336, 2011, we analyze phase and amplitude data recorded by GPS receivers separated by a few hundred meters in a low earth orbit and derive collocated atmospheric refractivity profiles. In the altitude range 10-20 km the standard deviation between TerraSAR-X and TanDEM-X refractivity does not exceed 0.15%. The standard deviation is rapidly increasing for lower and higher altitudes; close to the surface and at an altitude of 30 km the standard deviation reaches 0.8% and 0.5%, respectively. Systematic deviations between TerraSAR-X and TanDEM-X refractivity in the considered altitude range (0-30 km) are negligible. The results confirm the anticipated high precision of the GPS RO technique. However, the difference in the retrieved refractivity in the lower troposphere for different Open Loop (OL) signal tracking parameters, altered onboard TanDEM-X for DOY 49-55, 2012, calls for an in depth analysis. At the moment we can not exclude that a potential bias in the OL Doppler model introduces a bias in our retrieved refractivity at altitudes <8 km.

Zus, Florian; Grunwaldt, Ludwig; Heise, Stefan; Michalak, Grzegorz; Schmidt, Torsten; Wickert, Jens

2014-01-01

193

Accuracy assessment of land cover dynamic in hill land on integration of DEM data and TM image  

NASA Astrophysics Data System (ADS)

To accurately assess the area of land cover in hill land, we integrated DEM data and remote sensing image in Lihe River Valley, China. Firstly, the DEM data was combined into decision tree to increase the accuracy of land cover classification. Secondly, a slope corrected model was built to transfer the projected area to surface area by DEM data. At last, the area of different land cover was calculated and the dynamic of land cover in Lihe River Valley were analyzed from 1998 to 2003. The results show that: the area of forestland increased more than 10% by the slope corrected model, that indicates the area correcting is very important for hill land; the accuracy of classification especially for forestland and garden plot is enhanced by integrating of DEM data. It can be greater than 85%. The indexes of land use extent were 266.2 in 1998, 273.1 in 2001, and 276.7 in 2003. The change rates of land use extent were 2.59 during 1998 to 2001 and 1.34 during 2001 to 2003.

Li, Yunmei; Wang, Xin; Wang, Qiao; Wu, Chuanqing; Huang, Jiazhu

2010-04-01

194

From Point Cloud to Grid DEM: A Scalable Pankaj K. Agarwal #1 , Lars Arge ##12 , and Andrew Danner ###1  

E-print Network

From Point Cloud to Grid DEM: A Scalable Approach Pankaj K. Agarwal #1 , Lars Arge ##12 20GB) in about 53 hours. Neither ArcGIS nor GRASS, two popular GIS products, were able to process this data set. 1 Introduction One of the basic tasks of a geographic information system (GIS) is to store

Danner, Andrew

195

Comparison of SIFT and SURF based DEM extraction approaches on a GEOEYE-1 satellite stereo-pair  

NASA Astrophysics Data System (ADS)

A MATLAB module for Digital Elevation Model (DEM) extraction from Very High Resolution (VHR) satellite stereo-pair imagery is used to compare the efficiency of two well established feature detection and description algorithms. A procedure for parallel processing of cascading image tiles is used for handling the large datasets requirements of VHR satellite imagery. Scale-Invariant Feature Transform (SIFT) and Speeded Up Robust Features (SURF) algorithms are used to detect potentially tentative feature matches in the members of the stereo-pair. The resulting feature pairs are filtered using the RANdom SAmple Consensus (RANSAC) algorithm by using a variable distance threshold. Finally, tentative feature matches are converted to point cloud ground coordinates for DEM generation. A 0.5 m × 0.5 m Geoeye-1 stereo-pair acquired over an area of 25 km2 in the island of Crete, Greece is used as input for the module. The resulting 2 m × 2 m DEMs has superior detail over previously developed 2 m and 5 m DEMs that are used as reference, and yields a Root Mean Square Error (RMSE) of about 1 m compared to ground truth measurements. Results suggest that SURF's superior runtime performance outweighs the slightly better feature quality attained with SIFT.

Daliakopoulos, Ioannis; Tsanis, Ioannis

2014-05-01

196

BOREAS HYP-8 DEM Data Over The NSA-MSA and SSA-MSA in The AEAC Projection  

NASA Technical Reports Server (NTRS)

These data were derived from the original Digital Elevation Models (DEMs) produced by the Boreal Ecosystem-Atmosphere Study (BOREAS) Hydrology (HYD)-8 team. The original DEMs were in the Universal Transverse Mercator (UTM) projection, while this product is projected in the Albers Equal-Area Conic (AEAC) projection. The pixel size of the data is 100 meters, which is appropriate for the 1:50,000-scale contours from which the DEMs were made. The original data were compiled from information available in the 1970s and 1980s. This data set covers the two Modeling Sub-Areas (MSAs) that are contained within the Southern Study Area (SSA) and the Northern Study Area (NSA). The data are stored in binary, image format files. The DEM data over the NSA-MSA and SSA-MSA in the AEAC projection are available from the Earth Observing System Data and Information System (EOSDIS) Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC). The data files are available on a CD-ROM (see document number 20010000884).

Knapp, David E.; Hall, Forrest G. (Editor); Wang, Xue-Wen; Band, L. E.; Smith, David E. (Technical Monitor)

2000-01-01

197

Exercise Lab: Where is the Himalaya eroding? Using GIS/DEM analysis to reconstruct surfaces, incision, and  

E-print Network

1 Exercise Lab: Where is the Himalaya eroding? Using GIS/DEM analysis to reconstruct surfaces similar). 5) Now you have a hillshade view of the Himalaya with drapedover elevation. 6) Let's import a spatial reference frame. The file we are using is in a Geographic projection (WGS84). Click on Advanced

Bookhagen, Bodo

198

Mapping hydrological environments in central Amazonia: ground validation and surface model based on SRTM DEM data corrected for deforestation  

NASA Astrophysics Data System (ADS)

One of the most important freely available digital elevation models (DEMs) for Amazonia is the one obtained by the Shuttle Radar Topography Mission (SRTM). However, since SRTM tends to represent the vegetation surface instead of the ground surface, the broad use of SRTM DEM as a framework for terrain description in Amazonia is hampered by the presence of deforested areas. We present here two datasets: (1) a deforestation-corrected SRTM DEM for the interfluve between the Purus and Madeira rivers, in central Amazonia, which passed through a careful identification of different environments and has deforestation features corrected by a new method of increasing pixel values of the DEM; and (2) a set of eighteen hydrological-topographic descriptors based on the corrected SRTM DEM. The hydrological-topographic description was generated by the Height Above the Nearest Drainage (HAND) algorithm, which normalizes the terrain elevation (a.s.l.) by the elevation of the nearest hydrologically connected drainage. The validation of the HAND dataset was done by in situ hydrological description of 110 km of walking trails also available in this dataset. The new SRTM DEM expands the applicability of SRTM data for landscape modelling; and the datasets of hydrological features based on topographic modelling is undoubtedly appropriate for ecological modelling and an important contribution for environmental mapping of Amazonia. The deforestation-corrected SRTM DEM is available at http://ppbio.inpa.gov.br/knb/metacat/naman.318.3/ppbio; the polygons selected for deforestation correction are available at http://ppbio.inpa.gov.br/knb/metacat/naman.317.3/ppbio; the set of hydrological-topographic descriptors is available at http://ppbio.inpa.gov.br/knb/metacat/naman.544.2/ppbio; and the environmental description of access trails is available at http://ppbio.inpa.gov.br/knb/metacat/naman.541.2/ppbio.

Moulatlet, G. M.; Rennó, C. D.; Costa, F. R. C.; Emilio, T.; Schietti, J.

2014-07-01

199

The effect of DEM resolution on the computation of the factor of safety using an infinite slope model  

NASA Astrophysics Data System (ADS)

The quality of digital elevation models (DEMs) is essential for reliable landslide susceptibility assessments. In this paper, two DEMs derived from ASTER (ASTER GDEM v.2 with 30 m horizontal resolution) and TerraSAR-X (GeoElevation10 with 10 m horizontal resolution) data are compared to study the effects of resolution on the derived slope and wetness index parameters in the application of the infinite slope model for the computation of the factor of safety. Several slope stability scenarios representing different wetness conditions with 5, 10 and 100 mm d- 1 of steady-state recharge were calculated for the eastern flank of Mount Rinjani Volcano on Lombok Island, Indonesia. Each scenario was conducted by computing the static factor of safety with mean values of the bulk density, angle of internal friction, cohesion, and failure depth parameters, as well as for their normally distributed values by Monte Carlo simulation. All scenarios were applied to both DEMs. The scenarios were evaluated by calculating the success/prediction rate using the respective area under the curve (AUC) and an existing landslide inventory. Additionally, uncertainties in the estimated positions of landslides were taken into account. Depending on the particular scenario, the success rate of the GeoElevation10 model shows differences up to 3% compared to the ASTER GDEM model. This apparent improvement is mainly caused by the higher ground resolution in GeoElevation10. However, the success rate increases for the 10 mm d- 1 and decreases for the 100 mm d- 1 steady-state recharge conditions. Consequently, the more detailed flow direction in the GeoElevation10 DEM has the highest impact under conditions with lower water saturation. The slight improvement in the total model quality shows that the higher resolution of the DEM has a small impact on poorly parameterized models, in which the material properties are described by roughly estimated parameters. Therefore, the application of a high-resolution DEM to areas with a lack of data on the soil's physical properties is inefficient due to its low cost-benefit ratio. For quick analysis, the ASTER GDEM is of a suitable quality. To fully benefit from the high resolution of the DEMs, other parameters should be available in appropriate detail.

Fuchs, Michael; Torizin, Jewgenij; Kühn, Friedrich

2014-11-01

200

Evaluation of terrain datasets for LiDAR data thinning and DEM generation for watershed delineation applications  

NASA Astrophysics Data System (ADS)

Watershed delineation based on Digital Elevation Models (DEM) is currently a standard practice in hydrologic studies. Efforts to develop DEMs of high resolution continues to take place, although the advantages of increasing the accuracy of the results are partially offset by the increased file size, difficulty to handle them, slow screen rendering and increase computational effort. Among these efforts, those based on the use of Light Detection and Ranging (LiDAR) pose the problem that interpolation techniques in commercially available GIS software packages (e.g., IDW, Spline, Kriging and TOPORASTER, among others) for developing DEMs from point elevations have difficulty processing large amounts of data. Terrain Dataset is an alternative format for storing topographic data that intelligently decimates data points and creates simplified, yet equally accurate for practical purposes, DEMs or Triangular Irregular Networks (TIN). This study uses terrain datasets to evaluate the impact that the thinning method (i.e., window size and z-value), pyramid level and the interpolation technique (linear or natural neighbor) used to create the DEMs have on the watersheds delineated from them. Two case studies were considered for assessing the effect of the different methods and techniques. One of them consisted of dendritic topography in Williamson Creek, Austin, Texas, and the other of deranged topography in Hillsborough County, Florida. The results were compared using three standardized error metrics that measure the accuracy of the watershed boundaries, and computational effort. For the Williamson creek (steeper terrain), point thinning during the terrain creation process or the interpolation method choice did not affect the watershed delineation; while, in the Hillsborough (flat terrain), the method for point thinning and interpolation techniques highly influenced the resulting watershed delineation.

Olivera, F.; Ferreira, C.; Djokic, D.

2010-12-01

201

Relationship between glomerular lesions, serum creatinine and interstitial volume in membrano-proliferative glomerulonephritis  

Microsoft Academic Search

Zusammenfassung An 33 Patienten mit membranoproliferativer GN verschiedener Schweregrade konnte gezeigt werden, daß keine sicheren Beziehungen zwischen Ausmaß der glomerulären Veränderungen und dem Serum-Kreatininspiegel bestehen.

H. Fischbach; S. Mackensen; K.-E. Grund; A. Kellner; A. Bohle

1977-01-01

202

The accuracy of photo-based structure-from-motion DEMs  

NASA Astrophysics Data System (ADS)

Data for detailed digital elevation models (DEMs) are usually collected by expensive laser-based techniques, or by photogrammetric methods that require expertise and specialist software. However, recent advances in computer vision research now permit 3D models to be automatically derived from unordered collections of photographs, offering the potential for significantly cheaper and quicker DEM production. Here, we assess the accuracy of this approach for geomorphological applications using examples from a coastal cliff and a volcanic edifice. The reconstruction process is based on a combination of structure-from-motion and multi-view stereo algorithms (SfM-MVS). Using multiple photographs of a scene taken from different positions with a consumer-grade camera, dense point clouds (millions of points) can be derived. Processing is carried out by automated 'reconstruction pipeline' software downloadable from the internet, e.g. http://blog.neonascent.net/archives/bundler-photogrammetry-package/. Unlike traditional photogrammetric approaches, the initial reconstruction process does not require the identification of any control points or initial camera calibration and is carried out with little or no operator intervention. However, such reconstructions are initally un-scaled and un-oriented so additional software (http://www.lancs.ac.uk/staff/jamesm/software/sfm_georef.htm) has been developed to permit georeferencing. Although this step requires the presence of some control points or features within the scene, it does not have the relatively strict image acquisition and control requirements of traditional photogrammetry. For accuracy, and to allow error analysis, georeferencing observations are made within the image set, rather than requiring feature matching within the point cloud. In our coastal example, 133 photos taken with a Canon EOS 450D and 28 mm prime lens, from viewing distances of ~20 m, were used to reconstruct a ~60 m long section of eroding cliff. The resulting surface model was compared with data collected by a Riegl LMS-Z210ii terrestrial laser scanner. Differences between the surfaces were dominated by the varying effects of occlusions on the techniques, and systematic distortion of the SfM-MVS model along the length of the cliff could not be resolved over the ±15 mm precision of the TLS data. For a larger-scale example, a ~1.6 km wide region over the summit of Piton de la Fournaise volcano was reconstructed using 133 photos taken with a Canon EOS D60 and 20 mm prime lens, from a microlight aircraft (with a representative viewing distance of 1.0 km). In this case, the resulting DEM showed an RMS error of 1.0 m when compared with the results from traditional photogrammetry and some areas of systematic error were evident. Such errors were minimised by reprocessing the SfM-MVS results with a more sophisticated camera model than is integrated into the reconstruction pipeline. In combination, the results indicate that, with a good, convergent image set, SfM-MVS can be anticipated to deliver relative precisions of 1:1000 or better, for geomorphological applications. However, under certain conditions, the restricted camera model used can result in detectable error. We highlight the requirement for new network design tools that will help optimise image collection, facilitate error visualisation and allow a user to determine whether their image network is fit for purpose.

James, M. R.; Robson, S.

2012-04-01

203

The Multi-Instrument, Comprehensive Differential Emission Measure (DEM) of the Solar Corona During Flares and Quiescent Periods  

NASA Astrophysics Data System (ADS)

Thermal plasma in the solar corona, while often modeled as isothermal for ease of analysis, is in fact decidedly multi-thermal, ranging from ~1-2 MK in the quiescent corona to ~30-50 MK in intensely flaring loops. It has proven difficult to obtain a well-constrained differential emission measure (DEM) from a single instrument, as the wavelength ranges of individual instruments, even those with broadband coverage, provide sensitivity to only a limited range of plasma temperatures. Recently, we developed a new technique using combined extreme ultraviolet (EUV) and soft and hard X-ray (SXR, HXR) data from the EUV Variability Experiment (EVE) onboard the Solar Dynamics Observatory (SDO) and the Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI), respectively, to obtain a self-consistent DEM that is strongly constrained across the full range of coronal plasma temperatures (<2 to >50 MK). An accurate, precise determination of the plasma temperature distribution enables not only studies of plasma heating and thermal plasma evolution, but can also provide strong constraints on the non-thermal accelerated electron population, including the low-energy cutoff which is typically determined only as a loose upper limit.We present EVE+RHESSI DEM results from selected intense (X-class) flares from solar cycle 24, including determining the non-thermal low-energy cutoff and examining how this evolves with the temperature distribution. We also apply this technique to combine EUV data from EVE with SXR data from the GOES X-ray Sensor (XRS) and the X123, a new SXR spectrometer flown on two recent SDO/EVE calibration sounding rockets, to examine the DEM during quiescent (non-flaring) times with varying activity levels; the X-ray data provide crucial constraints on the high-temperate extent of the DEM and any potential non-thermal emission. We compare these results with those from a parallel technique to derive DEMs from imaging data from the Atmospheric Imaging Assembly (AIA) onboard SDO, and we discuss the implications for plasma heating, both during flares and in the quiescent corona. This research is supported by NASA contracts NAS5-98033 and NAS5-02140, and NASA Heliophysics Guest Investigator Grant NNX12AH48G.

Caspi, Amir; McTiernan, James; Warren, Harry; Woods, Thomas N.

2014-06-01

204

Discrete element method (DEM) simulations of stratified sampling during solid dosage form manufacturing.  

PubMed

Discrete element model (DEM) simulations of the discharge of powders from hoppers under gravity were analyzed to provide estimates of dosage form content uniformity during the manufacture of solid dosage forms (tablets and capsules). For a system that exhibits moderate segregation the effects of sample size, number, and location within the batch were determined. The various sampling approaches were compared to current best-practices for sampling described in the Product Quality Research Institute (PQRI) Blend Uniformity Working Group (BUWG) guidelines. Sampling uniformly across the discharge process gave the most accurate results with respect to identifying segregation trends. Sigmoidal sampling (as recommended in the PQRI BUWG guidelines) tended to overestimate potential segregation issues, whereas truncated sampling (common in industrial practice) tended to underestimate them. The size of the sample had a major effect on the absolute potency RSD. The number of sampling locations (10 vs. 20) had very little effect on the trends in the data, and the number of samples analyzed at each location (1 vs. 3 vs. 7) had only a small effect for the sampling conditions examined. The results of this work provide greater understanding of the effect of different sampling approaches on the measured content uniformity of real dosage forms, and can help to guide the choice of appropriate sampling protocols. PMID:21635943

Hancock, Bruno C; Ketterhagen, William R

2011-10-14

205

CFD-DEM study of effect of bed thickness for bubbling fluidized beds  

SciTech Connect

The effect of bed thickness in rectangular fluidized beds is investigated through the CFD–DEM simulations of small-scale systems. Numerical results are compared for bubbling fluidized beds of various bed thicknesses with respect to particle packing, bed expansion, bubble behavior, solids velocities, and particle kinetic energy. Good two-dimensional (2D) flow behavior is observed in the bed having a thickness of up to 20 particle diameters. However, a strong three-dimensional (3D) flow behavior is observed in beds with a thickness of 40 particle diameters, indicating the transition from 2D flow to 3D flow within the range of 20–40 particle diameters. Comparison of velocity profiles near the walls and at the center of the bed shows significant impact of the front and back walls on the flow hydrodynamics of pseudo-2D fluidized beds. Hence, for quantitative comparison with experiments in pseudo-2D columns, the effect of walls has to be accounted for in numerical simulations.

Tingwen, Li; Gopalakrishnan, Pradeep; Garg, Rahul; Shahnam, Mehrdad

2011-10-01

206

Cooperative dynamics of a group of intruders subsiding in granular media: A DEM study  

NASA Astrophysics Data System (ADS)

We numerically investigated the subsidence of a group of solid intruders in a randomly generated granular bed using discrete element method (DEM) in 2D and explored the cooperative behaviour of these intruders. Five intruders with a specified separation distance were placed on the surface of the granular bed and released to subside with zero impact velocity. Dynamics of the intruders was analysed. In addition, the effects of friction, boundary constraints, and the diameter and density ratio of the intruders to particles in the granular bed on the cooperative dynamics were also examined. It was found that friction and boundary constraints significantly affected the subsiding kinematics of the intruders. Most interestingly, it was shown that the intruders subside in a cooperative manner as they initially split from each other, and then move toward each other, resembling the flying pattern of a flock of birds in the air. This cooperative behaviour is in broad agreement with the experimental observations of Pacheco-Vazquez and Ruiz-Suarez (2010).

Goey, Cher Hui; Wu, Chuan-Yu

2013-06-01

207

Classification of topography using DEM data and its correlation with the geology of Greece  

NASA Astrophysics Data System (ADS)

Continuous topography from Digital Elevation Model (DEM) data is frequently segmented into terrain classes based on local morphological characteristics of terrain elevation, e.g., local slope gradient and convexity. The resulting classes are often used as proxies for the average shear wave velocity up to 30 m, and the determination of ground types as required by the Eurocode (EC8) for computing elastic design spectra. In this work, we investigate the links between terrain related variables, particularly slope gradient, extracted for the area of Greece from the Shuttle Radar Topography Mission (SRTM) 30 arc second global topographic data available from the United States Geological Survey (USGS), with: (a) the global terrain classification product of Iwahashi and Pike (2007) in which 16 terrain types are identified for the same spatial resolution, and (b) information on geological units extracted at the same resolution from the geological map of Greece at a scale of 1/500000 as published from the Institute of Geology and Mineral Exploration (IGME). An interpretation of these links is presented within the context of understanding the reliability of using geology, slope and terrain classes for site characterizations of earthquake risk in a high seismicity area like Greece. Our results indicate that slope is a somewhat biased proxy for solid rocks, whereas in Alluvial deposits the distance to and type of the nearest geological formation appears to provide qualitative information on the size of the sedimentary deposit.

Zargli, Eleni; Liodakis, Stelios; Kyriakidis, Phaedon; Savvaidis, Alexandros

2013-08-01

208

Beziehungen zwischen Menschenbild und Psychotherapíe  

Microsoft Academic Search

The part played by psychotherapy in the treatment of different clinical conditions such as functional disturbances, neuroses, psychosomatic disease and a variety of somatic diseases varies in importance. It can be the treatment, an important part of a course of treatment, or only supportive to other clinical measures. In spite of differences in psycho-therapeutic approach, all forms of psychotherapy have

Christa Kohler; Karl Seidel

1974-01-01

209

Optimizing photogrammetric DEMs for glacier volume change assessment using laser-scanning derived ground-control points  

Microsoft Academic Search

Photogrammetric processing of archival stereo imagery offers the opportunity to reconstruct glacier volume changes for regions where no such data exist, and to better constrain the contribution to sea-level rise from small glaciers and ice caps. The ability to derive digital elevation model (DEM) measurements of glacier volume from photogrammetry relies on good-quality, well-distributed ground reference data, which may be

Nicholas E. Barrand; Tavi Murray; Timothy D. James; Stuart L. Barr; Jon P. Mills

2009-01-01

210

Instruments and Methods Optimizing photogrammetric DEMs for glacier volume change assessment using laser-scanning derived ground-control points  

Microsoft Academic Search

Photogrammetric processing of archival stereo imagery offers the opportunity to reconstruct glacier volume changes for regions where no such data exist, and to better constrain the contribution to sea-level rise from small glaciers and ice caps. The ability to derive digital elevation model (DEM) measurements of glacier volume from photogrammetry relies on good-quality, well-distributed ground reference data, which may be

Nicholas E. BARRAND; Tavi MURRAY; Timothy D. JAMES; Stuart L. BARR; Jon P. MILLS

211

Quantifying Ice-sheet/Ice-shelf Dynamics and Variability with Meter-scale DEM and Velocity Timeseries  

NASA Astrophysics Data System (ADS)

Both the Antarctic and Greenland ice sheets are losing mass at an increasing rate, although loss due to accelerating flow and dynamic thinning remains poorly understood. We are using complementary data from repeat satellite and airborne observations to investigate the relationship between ice-sheet/ice-shelf dynamics and geometry on seasonal to interannual timescales. High-resolution along-track stereo imagery from commercial satellite vendors DigitalGlobe and GeoEye provides unprecedented spatial (~0.5 m/px with ~17 km swath width) and temporal (weekly/monthly) resolution for these efforts. We have developed an automated pipeline using open-source software to produce orthoimage, DEM, and surface velocity products from DigitalGlobe imagery. High-contrast surface texture (e.g. sastrugi, crevasses) visible at sub-meter resolution provides near-perfect image correlation (~99% success rate) during DEM and velocity map derivation. Elevation data from IceBridge ATM/LVIS, ICESat GLAS, and GPS campaigns are used to correct DEMs and perform accuracy assessment. Preliminary tests over exposed bedrock provide relative vertical accuracy estimates of <1-2 m for Worldview-1/2 DEMs. Velocity data from TerraSAR-X and GPS campaigns provide validation for surface velocity products, with horizontal error estimates of <10 m. Velocity and elevation change products with 2-4 m/px spatial resolution allow for unprecedented 3D dynamic characterization of sub-km flow transition zones (e.g. grounding lines, shear margins), capturing both local and regional variations due to melting and dynamic thinning. We present timeseries for West Greenland (Jakobshavn front - 20 observations, Jakobshavn south catchment - 10) and West Antarctica (Pine Island and Thwaites - 5 each) from 2009-2012. These observations complement ongoing efforts to measure and model outlet glacier dynamics, with implications for future ice-sheet mass balance estimates.

Shean, D. E.; Joughin, I. R.; Smith, B. E.; Moratto, Z. M.; Porter, C.; Morin, P. J.

2012-12-01

212

Verbesserte Berechnung der Wasserstoffverteilung im Sicherheitsbehälter bei der Analyse schwerer Störfälle in Kernkraftwerken durch Kopplung von MELCOR und GASFLOW (KIT Scientific Reports ; 7658).  

E-print Network

??Der Bericht beschreibt die Entwicklung einer Kopplung zwischen dem integralen Störfall-Code MELCOR und dem CFD-Code GASFLOW, welcher die Wasserstoffverteilung im Reaktorsicherheitsbehälter berechnet. Der korrekte Datenaustausch… (more)

Szabó, Tobias

2014-01-01

213

Optimizing photogrammetric DEMs for glacier volume change assessment using laser-scanning derived ground-control points  

NASA Astrophysics Data System (ADS)

Photogrammetric processing of archival stereo imagery offers the opportunity to reconstruct glacier volume changes for regions where no such data exist, and to better constrain the contribution to sea-level rise from small glaciers and ice caps. The ability to derive digital elevation model (DEM) measurements of glacier volume from photogrammetry relies on good-quality, well-distributed ground reference data, which may be difficult to acquire. This study shows that ground-control points (GCPs) can be identified and extracted from point-cloud airborne lidar data and used to control photogrammetric glacier models. The technique is applied to midtre Lovénbreen, a small valley glacier in northwest Svalbard. We show that the amount of ground control measured and the elevation accuracy of GCP coordinates (based on known and theoretical error considerations) has a significant effect on photogrammetric model statistics, DEM accuracy and the subsequent geodetic measurement of glacier volume change. Models controlled with fewer than 20 lidar control points or GCPs from sub-optimal areas within the swath footprint overestimated volume change by 14-53% over a 2 year period. DEMs derived from models utilizing 20-25 or more GCPs, however, gave volume change estimates within ˜4% of those from repeat lidar data (-0.51 ma-1 between 2003 and 2005). Our results have important implications for the measurement of glacier volume change from archival stereo-imagery sources.

Barrand, Nicholas E.; Murray, Tavi; James, Timothy D.; Barr, Stuart L.; Mills, Jon P.

214

Release of a 10-m-resolution DEM for the whole Italian territory: a new, freely available resource for research purposes  

NASA Astrophysics Data System (ADS)

Digital elevation models (DEMs) are fundamental in any kind of environmental or morphological study. DEMs are obtained from a variety of sources and generated in several ways. Nowadays, a few global-coverage elevation datasets are available for free (e.g., SRTM, http://www.jpl.nasa.gov/srtm; ASTER, http://asterweb.jpl.nasa.gov/). When the matrix of a DEM is used also for computational purposes, the choice of the elevation dataset which better suits the target of the study is crucial. Recently, the increasing use of DEM-based numerical simulation tools (e.g. for gravity driven mass flows), would largely benefit from the use of a higher resolution/higher accuracy topography than those available at planetary scale. Similar elevation datasets are neither easily nor freely available for all countries worldwide. Here we introduce a new web resource which made available for free (for research purposes only) a 10 m-resolution DEM for the whole Italian territory. The creation of this elevation dataset was presented by Tarquini et al. (2007). This DEM was obtained in triangular irregular network (TIN) format starting from heterogeneous vector datasets, mostly consisting in elevation contour lines and elevation points derived from several sources. The input vector database was carefully cleaned up to obtain an improved seamless TIN refined by using the DEST algorithm, thus improving the Delaunay tessellation. The whole TINITALY/01 DEM was converted in grid format (10-m cell size) according to a tiled structure composed of 193, 50-km side square elements. The grid database consists of more than 3 billions of cells and occupies almost 12 GB of disk memory. A web-GIS has been created (http://tinitaly.pi.ingv.it/ ) where a seamless layer of images in full resolution (10 m) obtained from the whole DEM (both in color-shaded and anaglyph mode) is open for browsing. Accredited navigators are allowed to download the elevation dataset.

Tarquini, S.; Nannipieri, L.; Favalli, M.; Fornaciai, A.; Vinci, S.; Doumaz, F.

2012-04-01

215

The influence of accuracy, grid size, and interpolation method on the hydrological analysis of LiDAR derived dems: Seneca Nation of Indians, Irving NY  

NASA Astrophysics Data System (ADS)

Light Detection and Ranging (LiDAR) derived Digital Elevation Models (DEMs) provide accurate, high resolution digital surfaces for precise topographic analysis. The following study investigates the accuracy of LiDAR derived DEMs by calculating the Root Mean Square Error (RMSE) of multiple interpolation methods with grid cells ranging from 0.5 to 10-meters. A raster cell with smaller dimensions will drastically increase the amount of detail represented in the DEM by increasing the number of elevation values across the study area. Increased horizontal resolutions have raised the accuracy of the interpolated surfaces and the contours generated from the digitized landscapes. As the raster grid cells decrease in size, the level of detail of hydrological processes will significantly improve compared to coarser resolutions including the publicly available National Elevation Datasets (NEDs). Utilizing a LiDAR derived DEM with the lowest RMSE as the 'ground truth', watershed boundaries were delineated for a sub-basin of the Clear Creek Watershed within the territory of the Seneca Nation of Indians located in Southern Erie County, NY. An investigation of the watershed area and boundary location revealed considerable differences comparing the results of applying different interpretation methods on DEM datasets of different horizontal resolutions. Stream networks coupled with watersheds were used to calculate peak flow values for the 10-meter NEDs and LiDAR derived DEMs.

Clarkson, Brian W.

216

Three-dimensional Distinct Element Method (DEM) modelling of oblique-slip normal faulting  

NASA Astrophysics Data System (ADS)

Normal faults frequently exhibit a strike-slip displacement component, which can arise for example from oblique reactivation or from fault strike changes, e.g. along bends. It is well known from both natural examples and analogue experiments that fault zones developing above oblique normal faults are typically comprised of systematically stepping fault segments. However, dependencies of fault segment orientation and segmentation on fault obliquity and mechanical properties during faulting are poorly understood. For example, it is not clear whether systematically stepping fault segments link preferentially via footwall or hanging wall breaching. Moreover, the persistence of fault bends throughout mechanically layered sequences is another yet unexplored topic. Here we use three-dimensional Distinct Element Method (DEM) modelling to elucidate the geometry and kinematics of fault zones developing above oblique normal faults. We systematically vary both fault obliquity and confining pressure. Fault zone structure (e.g. segment orientations, drag, etc.) is quantified from horizon maps generated at different levels within the model. Irrespective of fault obliquity, fault zones become better localised with increasing confining pressure. Analysis of displacement partitioning at branch-points illustrates that neither footwall nor hanging wall breaching is the preferred mode of segment linkage. Fault segment orientations exhibit a systematic fault obliquity dependence, which can be rationalised using infinitesimal strain theory for transtensional shear zones. Our models therefore suggest that the orientation of fault segments developing above oblique normal faults may be used to estimate the extension direction, as suggested nearly 30 years ago by A.M. McCoss [1986, J. Struct. Geol. 8(6), p. 715-718].

Schöpfer, Martin; Childs, Conrad; Manzocchi, Tom; Walsh, John

2014-05-01

217

New insights from DEM's into form, process and causality in Distributive Fluvial Systems  

NASA Astrophysics Data System (ADS)

Recent developments in platforms and sensors, as well as advances in our ability to access these rich data sources in near real time presents geoscientists with both opportunities and problems. We currently record raster and point cloud data about the physical world at unprecedented rates with extremely high spatial and spectral resolution. Yet the ability to extract scientifically useful knowledge from such immense data sets has lagged considerably. The interrelated fields of database creation, data mining and modern geostatistics all focus on such interdisciplinary data analysis problems. In recent years these fields have made great advances in analyzing the complex real-world data such as that captured in Digital Elevation Models (DEM's) and satellite imagery and by LIDAR and other geospatially referenced data sets. However, even considering the vast increase in the use of these data sets in the past decade these methods have enjoyed only a relatively modest penetration into the geosciences when compared to data analysis in other scientific disciplines. In part, a great deal of the current research weakness is due to the lack of a unifying conceptual approach and the failure to appreciate the value of highly structured and synthesized compilations of data, organized in user-friendly formats. We report on the application of these new technologies and database approaches to global scale parameterization of Distributive Fluvial Systems (DFS) within continental sedimentary basins and illustrate the value of well-constructed databases and tool-rich analysis environments for understanding form, process and causality in these systems. We analyzed the characteristics of aggradational fluvial systems in more than 700 modern continental sedimentary basins and the links between DFS within these systems and their contributing drainage basins. Our studies show that in sedimentary basins, distributive fluvial and alluvial systems dominate the depositional environment. Consequently, we have found that studies of modern tributary drainage systems in degradational settings are likely insufficient for understanding the geomorphology expressed within these basins and ultimately for understanding the basin-scale architecture of dominantly distributive fluvial deposits preserved in the rock record.

Scuderi, Louis; Weissmann, Gary; Hartley, Adrian; Kindilien, Peter

2014-05-01

218

Forecasting of Storm-Surge Floods Using ADCIRC and Optimized DEMs  

NASA Technical Reports Server (NTRS)

Increasing the accuracy of storm-surge flood forecasts is essential for improving preparedness for hurricanes and other severe storms and, in particular, for optimizing evacuation scenarios. An interactive database, developed by WorldWinds, Inc., contains atlases of storm-surge flood levels for the Louisiana/Mississippi gulf coast region. These atlases were developed to improve forecasting of flooding along the coastline and estuaries and in adjacent inland areas. Storm-surge heights depend on a complex interaction of several factors, including: storm size, central minimum pressure, forward speed of motion, bottom topography near the point of landfall, astronomical tides, and, most importantly, maximum wind speed. The information in the atlases was generated in over 100 computational simulations, partly by use of a parallel-processing version of the ADvanced CIRCulation (ADCIRC) model. ADCIRC is a nonlinear computational model of hydrodynamics, developed by the U.S. Army Corps of Engineers and the US Navy, as a family of two- and three-dimensional finite-element-based codes. It affords a capability for simulating tidal circulation and storm-surge propagation over very large computational domains, while simultaneously providing high-resolution output in areas of complex shoreline and bathymetry. The ADCIRC finite-element grid for this project covered the Gulf of Mexico and contiguous basins, extending into the deep Atlantic Ocean with progressively higher resolution approaching the study area. The advantage of using ADCIRC over other storm-surge models, such as SLOSH, is that input conditions can include all or part of wind stress, tides, wave stress, and river discharge, which serve to make the model output more accurate. To keep the computational load manageable, this work was conducted using only the wind stress, calculated by using historical data from Hurricane Camille, as the input condition for the model. Hurricane storm-surge simulations were performed on an eight-node Linux computer cluster. Each node contained dual 2-GHz processors, 2GB of memory, and a 40GB hard drive. The digital elevation model (DEM) for this region was specified using a combination of Navy data (over water), NOAA data (for the coastline), and optimized Interferometric Synthetic Aperture Radar data (over land). This high-resolution topographical data of the Mississippi coastal region provided the ADCIRC model with improved input with which to calculate improved storm-surge forecasts.

Valenti, Elizabeth; Fitzpatrick, Patrick

2006-01-01

219

Sudan und Sd-Sudan. Vom Konflikt zur Kooperation?  

E-print Network

Sudan und Süd-Sudan. Vom Konflikt zur Kooperation? Professor Dr. Karl Wohlmuth (Fachbereich aktuellen Konflikte zwischen dem Sudan und dem Süd-Sudan haben, wie die Konflikte innerhalb der beiden internationalen Grenze zwischen Sudan und Süd-Sudan mobilisiert werden können. Schon vor der Unabhängigkeit des

Koenig, Friederike - Fachbereich 2 Biologie

220

Dry coating in a high shear mixer: Comparison of experimental results with DEM analysis of particle motions  

NASA Astrophysics Data System (ADS)

Experimental dry coating of guest particles on the surface of host particles is performed by mechanical forces in a high shear mixer called "Cyclomix". The studied system (a mixture of particles of sugar, "Suglet™" as host particles and magnesium stearate as guest particles) was chosen as a model one to achieve better understandings of the phenomena during mixing. To simulate the flow of host/guest particles in the mixer, the Discrete Element Method (DEM) was applied. Experimental results such as flowability and wettability can be explained by particles flows evolutions with different rotational speed or duration treatment inside the Cyclomix.

Serris, E.; Sato, A.; Chamayou, A.; Galet, L.; Baron, M.; Grosseau, P.; Thomas, G.

2013-06-01

221

Visualising shear stress distribution inside flow geometries containing pharmaceutical powder excipients using photo stress analysis tomography and DEM simulations  

NASA Astrophysics Data System (ADS)

For the first time, photo stress analysis tomography (PSAT) is applied to probe the distribution of maximum shear stress and direction of major principal stress field within `powder' assemblies inside hopper geometries, and further supported by discrete element model (DEM) simulations. The results show that for decrease in hopper angle, the direction of major principle stress aligns with the direction of gravity which could promote flow rate under dynamic conditions. Conversely, the propensity of developing relatively more non-homogeneous distribution of shear resistance zones inside powder assemblies increases with the hopper angle, which could subsequently decrease their macroscopic flow rate.

Albaraki, Saeed; Antony, S. Joseph.; Arowosola, C. Babatunde

2013-06-01

222

The Discrete Equation Method (DEM) for Fully Compressible Two-Phase Flows in Ducts of Spatially Varying Cross-Section  

SciTech Connect

Typically, multiphase modeling begins with an averaged (or homogenized) system of partial differential equations (traditionally ill-posed) then discretizes this system to form a numerical scheme. Assuming that the ill-posedness problem is avoided by using a well-posed formulation such as the seven-equation model, this presents problems for the numerical approximation of non-conservative terms at discontinuities (interfaces, shocks) as well as unwieldy treatment of fluxes with seven waves. To solve interface problems without conservation errors and to avoid this questionable determination of average variables and the numerical approximation of the non-conservative terms associated with 2 velocity mixture flows we employ a new homogenization method known as the Discrete Equations Method (DEM). Contrary to conventional methods, the averaged equations for the mixture are not used, and this method directly obtains a (well-posed) discrete equation system from the single-phase system to produce a numerical scheme which accurately computes fluxes for arbitrary numbers of phases and solves non-conservative products. The method effectively uses a sequence of single phase Riemann equation solves. Phase interactions are accounted for by Riemann solvers at each interface. Flow topology can change with changing expressions for the fluxes. Non-conservative terms are correctly approximated. Some of the closure relations missing from the traditional approach are automatically obtained. Lastly, we can often times identify the continuous equation system, resulting from taking the continuous limit with weak wave assumptions, of the discrete equations. This can be very useful from a theoretical standpoint. As a first step toward implict integration of the DEM method in multidimensions, in this paper we construct a DEM model for the flow of two compressible phases in 1-D ducts of spatially varying cross-section to test this approach. To relieve time step size restrictions due to stiffness and to achieve tighter coupling of equations, a fully implicit time integration method is employed. For the first time, we demonstrate on a converging-diverging two-phase nozzle that this well-posed, 2 pressure, 2 velocity DEM model can be integrated to a meaningful steady-state with both phases treated as compressible.

Ray A. Berry; Richard Saurel; Tamara Grimmett

2009-07-01

223

Extracting Precise and Affordable Dems Despite of the Clouds. Ajax: the Joining of Radar and Optical Strengths  

NASA Astrophysics Data System (ADS)

On the one hand, onboard SPOT 5, the HRS instrument systematically collects stereopairs around the Globe since 2002. Each stereopair can encompass an area up to 600 km x 120 km within a single pass (i.e. 72 000 km² stereoscopic strips). Covering now more than 120 millions sq.km of the Earth landmasses, SPOT 5 stereoscopic imagery has become one of main satellite data sources for accurate DEM extraction, at least where the cloud coverage leaves a chance to do so ! On the other hand, the TerraSAR-X satellite, launched in June 2007, is able to collect radar data through the clouds in several modes. An approach to extract height information by radargrammetry was developed, and the commercial distribution of Digital Elevation Models based on TerraSAR-X StripMap and SpotLight Modes (resp. 3m and 1m resolution) has started in 2010. To improve the overall height accuracy of the DEM, acquisitions from both orbit directions are utilised, each point on the ground being thus imaged at least 4 times by TerraSAR-X. Since 2002, Spot Image and French National Cartographic Institute (IGN) are building a worldwide database called Elevation30/Reference3D™, which includes a Digital Elevation Model at 1-arc-second resolution (DTED level 2) extracted from HRS stereopairs. To answer the wide demand of precise DEMs over Tropical and Northern areas, frequently covered by clouds, a study was performed to integrate StripMap radargrammetric TerraSAR-X data into the Reference3D process, and two prototype products were issued, over Colombia and Congo areas. During this experiment, efforts have been made to stick to technical steps that could be integrated within a standardized production process, in order to keep offering affordable prices while maintaining a high standard of horizontal and vertical accuracy. The DEMs extracted from TerraSAR-X and HRS proved extremely consistent with each other, showing a mean difference of 0.80m. This allows to propose a unified Elevation30 product to the users, with a guaranteed accuracy materialized into the product through a dedicated vertical Accuracy Commitment Mask.

Cunin, 1 L.; Nonin, 2 P.; Janoth, 3 J.; Bernard, 4 M.

2012-07-01

224

TanDEM-X mission-new perspectives for the inventory and monitoring of global settlement patterns  

NASA Astrophysics Data System (ADS)

TerraSAR-X add-on for digital elevation measurement (TanDEM-X) is a German Earth observation mission collecting a total of two global coverages of very high resolution (VHR) synthetic aperture radar (SAR) X-band data with a spatial resolution of around three meters in the years 2011 and 2012. With these, the TanDEM-X mission (TDM) will provide a unique data set which is complementary to existing global coverages based on medium (MR) or high resolution (HR) optical imagery. The capabilities of the TDM in terms of supporting the analysis and monitoring of global human settlement patterns are explored and demonstrated. The basic methodology for a fully-operational detection and delineation of built-up areas from VHR SAR data is presented along with a description of the resulting geo-information product-the urban footprint (UF) mask-and the operational processing environment for the UF production. Moreover, potential follow-on analyses based on the intermediate products generated in the context of the UF analysis are introduced and discussed. The results of the study indicate the high potential of the TDM with respect to an analysis of urbanization patterns, peri-urbanization, spatio-temporal dynamics of settlement development as well as population estimation, vulnerability assessment and modeling of global change.

Esch, Thomas; Taubenböck, Hannes; Roth, Achim; Heldens, Wieke; Felbier, Andreas; Thiel, Michael; Schmidt, Martin; Müller, Andreas; Dech, Stefan

2012-01-01

225

Modeling the motion and orientation of various pharmaceutical tablet shapes in a film coating pan using DEM.  

PubMed

Film coating uniformity is an important quality attribute of pharmaceutical tablets. Large variability in coating thickness can limit process efficiency or cause significant variation in the amount or delivery rate of the active pharmaceutical ingredient to the patient. In this work, the discrete element method (DEM) is used to computationally model the motion and orientation of several novel pharmaceutical tablet shapes in a film coating pan in order to predict coating uniformity. The model predictions are first confirmed with experimental data obtained from an equivalent film coating pan using a machine vision system. The model is then applied to predict coating uniformity for various tablet shapes, pan speeds, and pan loadings. The relative effects of these parameters on both inter- and intra-tablet film coating uniformity are assessed. The DEM results show intra-tablet coating uniformity is strongly influenced by tablet shape, and the extent of this can be predicted by a measure of the tablet shape. The tablet shape is shown to have little effect on the mixing of tablets, and thus, the inter-tablet coating uniformity. The pan rotation speed and pan loading are shown to have a small effect on intra-tablet coating uniformity but a more significant impact on inter-tablet uniformity. These results demonstrate the usefulness of modeling in guiding drug product development decisions such as selection of tablet shape and process operating conditions. PMID:21356296

Ketterhagen, William R

2011-05-16

226

Co-seismic landslide topographic analysis based on multi-temporal DEM-A case study of the Wenchuan earthquake.  

PubMed

Hillslope instability has been thought to be one of the most important factors for landslide susceptibility. In this study, we apply geomorphic analysis using multi-temporal DEM data and shake intensity analysis to evaluate the topographic characteristics of the landslide areas. There are many geomorphologic analysis methods such as roughness, slope aspect, which are also as useful as slope analysis. The analyses indicate that most of the co-seismic landslides occurred in regions with roughness, hillslope and slope aspect of >1.2, >30, and between 90 and 270, respectively. However, the intersection regions from the above three methods are more accurate than that derived by applying single topographic analysis method. The ground motion data indicates that the co-seismic landslides mainly occurred on the hanging wall side of Longmen Shan Thrust Belt within the up-down and horizontal peak ground acceleration (PGA) contour of 150 PGA and 200 gal, respectively. The comparisons of pre- and post-earthquake DEM data indicate that the medium roughness and slope increased, the roughest and steepest regions decreased after the Wenchuan earthquake. However, slope aspects did not even change. Our results indicate that co-seismic landslides mainly occurred at specific regions of high roughness, southward and steep sloping areas under strong ground motion. Co-seismic landslides significantly modified the local topography, especially the hillslope and roughness. The roughest relief and steepest slope are significantly smoothed; however, the medium relief and slope become rougher and steeper, respectively. PMID:24171155

Ren, Zhikun; Zhang, Zhuqi; Dai, Fuchu; Yin, Jinhui; Zhang, Huiping

2013-01-01

227

Developing and programming a watershed traversal algorithm (WTA) in GRID-DEM and adapting it to hydrological processes  

NASA Astrophysics Data System (ADS)

A methodology for programming hydrological processes into watersheds using grid-type digital elevation models (DEMs) is investigated. This methodology is based on the basic configuration of the flow directions structure in the DEM, which is stored in files where information about topological relations and other frequently used features are saved. Some basic functions for managing topological data that significantly simplify the source code programming are also presented and described. We develop an algorithm that runs the entire drainage network in a watershed in both directions, upwards and downwards, which is ideal for incorporating structural models of hydrological processes that occur in basins or assessing its characteristics. The main attribute of this method is that information about hydrological processes and properties is transmitted during the routing from one area to another of the basin. The information is used when developing models of these hydrological processes and transmitted throughout the basin. At the end of the article, using this methodology with the SHEE software is illustrated with some examples.

Mateo Lázaro, Jesús; Sánchez Navarro, José Ángel; García Gil, Alejandro; Edo Romero, Vanesa

2013-02-01

228

DEM-based Approaches for the Identification of Flood Prone Areas  

NASA Astrophysics Data System (ADS)

The remarkable number of inundations that caused, in the last decades, thousands of deaths and huge economic losses, testifies the extreme vulnerability of many Countries to the flood hazard. As a matter of fact, human activities are often developed in the floodplains, creating conditions of extremely high risk. Terrain morphology plays an important role in understanding, modelling and analyzing the hydraulic behaviour of flood waves. Research during the last 10 years has shown that the delineation of flood prone areas can be carried out using fast methods that relay on basin geomorphologic features. In fact, the availability of new technologies to measure surface elevation (e.g., GPS, SAR, SAR interferometry, RADAR and LASER altimetry) has given a strong impulse to the development of Digital Elevation Models (DEMs) based approaches. The identification of the dominant topographic controls on the flood inundation process is a critical research question that we try to tackle with a comparative analysis of several techniques. We reviewed four different approaches for the morphological characterization of a river basin with the aim to provide a description of their performances and to identify their range of applicability. In particular, we explored the potential of the following tools. 1) The hydrogeomorphic method proposed by Nardi et al. (2006) which defines the flood prone areas according to the water level in the river network through the hydrogeomorphic theory. 2) The linear binary classifier proposed by Degiorgis et al. (2012) which allows distinguishing flood-prone areas using two features related to the location of the site under exam with respect to the nearest hazard source. The two features, proposed in the study, are the length of the path that hydrologically connects the location under exam to the nearest element of the drainage network and the difference in elevation between the cell under exam and the final point of the same path. 3) The method by Manfreda et al. (2011) that suggested a modified Topographic Index (TIm) for the identification of flood prone area. 4) The downslope index proposed by Hjerdt et al. (2004) that quantifies the topographic controls on hydrology by evaluating head differences following the (surface) flow path in the steepest direction. The method does not use the exit point at the stream as reference; instead, the algorithm looks at how far a parcel of water has to travel along its flow path to lose a given head potential, d [m]. This last index was not defined with the aim to describe flood prone areas; in fact it represents an interesting alternative descriptor of morphological features that deserve to be tested. Analyses have been carried out for some Italian catchments. The outcomes of the four methods are presented using, for calibration and validation purposes, flood inundation maps made available by River Basin Authorities. The aim is, therefore, to evaluate the reliability and the relative errors in the detection of the areas subject to the flooding hazard. These techniques should not be considered as an alternative of traditional procedures, but additional tool for the identification of flood-prone areas and hazard graduation over large regions or when a preliminary identification is needed. Reference Degiorgis M., G. Gnecco, S. Gorni, G. Roth, M. Sanguineti, A. C. Taramasso, Classifiers for the detection of flood-prone areas using remote sensed elevation data, J. Hydrol., 470-471, 302-315, 2012. Hjerdt, K. N., J. J. McDonnell, J. Seibert, A. Rodhe, A new topographic index to quantify downslope controls on local drainage, Water Resour. Res., 40, W05602, 2004. Manfreda, S., M. Di Leo, A. Sole, Detection of Flood Prone Areas using Digital Elevation Models, Journal of Hydrologic Engineering, Vol. 16, No. 10, 781-790, 2011. Nardi, F., E. R. Vivoni, S. Grimaldi, Investigating a floodplain scaling relation using a hydrogeomorphic delineation method, Water Resour. Res., 42, W09409, 2006.

Samela, Caterina; Manfreda, Salvatore; Nardi, Fernando; Grimaldi, Salvatore; Roth, Giorgio; Sole, Aurelia

2013-04-01

229

The mass balance record and surge behavior of Drangajökull Ice Cap (Iceland) from 1946 to 2011 deduced from aerial photographs and LiDAR DEM  

NASA Astrophysics Data System (ADS)

High resolution and accuracy (e.g. based on LiDAR survey) Digital Elevation Models (DEMs) of glaciers and their close vicinity have significantly improved the methods for calculation of geodetic mass balance and study of changes in glacier dynamics. However additional data is needed to extend such studies back in time. Here we present a geodetically derived mass balance record for Drangajökull ice cap (NW-Iceland) since 1946 to present. The mass balance is calculated from a series of DEMs derived by photogrammetric processing of aerial photographs (years: 1946, 1975, 1985, 1994) and a LiDAR DEM (2011). All Ground Control Points (GCPs) used to constrain the orientation of the aerial photographs, used in the photogrammetric processing, are picked from the LiDAR derived DEM, thus eliminating the time consuming and expensive in situ survey of GCPs. The LiDAR DEM also helps to assess the accuracy of the photogrammetrically derived DEMs, by analyzing the residuals in elevation in ice-free areas. For the DEMs of 1975, 1985 and 1994 the Root Mean Square Error (RMSE) of the residuals is less than 2 m, whereas the accuracy of the DEM of 1946 is worse, with RMSE of 5.5 m, caused by the deteriorated images. The geodetic mass balance yields a negative specific mass balance of ~-0.5 m w.e.a-¹ for the period 1946-1975, followed by periods of positive mass balance: ~0.2 m w.e.a-¹ for the period 1975-1985 and ~0.3 m w.e.a-¹ for the period 1985-1994. Negative specific mass balance of ~-0.6 m w.e.a-¹ is derived for the period 1994-2011. High mass redistribution is observed during 1985-1994 and 1994-2011 on the three main outlets of the ice cap, related to surges. The derived orthophotographs allow tracking of stable features at individual locations on the northern part of Drangajökull, indicating an average velocity of 5-10 m a-¹ for the period 1946-1985 and speeding up in the last two periods due to a surge.

Muñoz-Cobo Belart, Joaquín; Magnússon, Eyjólfur; Pálsson, Finnur

2014-05-01

230

Machine vision approach to auto-generation of high resolution, continental-scale geomorphometric map from DEM  

NASA Astrophysics Data System (ADS)

Geomorphometric map (GM) is a map of landforms delineated exclusively on the basis of their morphology; it depicts a classification of landscape into its constituent elements. GM is a valuable tool for visual terrain analysis, but more importantly, it's a perfect terrain representation for its further algorithmic analysis. GMs themselves are auto-generated from DEM. We have developed a new technique for auto-generation of GMs that is based on the principle of machine vision. Such approach approximates more closely the mapping process of human analyst and results in an efficient generation of GMs having quality and utility superior to maps generated by a standard technique based on differential geometry. The core of the new technique is a notion of geomorphon. A geomorphon is a relief-invariant, orientation-invariant, and size-flexible abstracted elementary unit of terrain. It is calculated from DEM using simple ternary patterns defined on a neighborhood which size adapts to the character of local terrain. Geomorphons are both terrain attributes and landform types at the same time; they allow for a direct and highly efficient, single-step classification and mapping of landforms. There are 498 unique geomorphons but only a small fraction of them are found in typical natural terrain. The geomorphon-based mapping technique is implemented as a GRASS GIS extension written in ANSI C and will be available in the public domain. In order to showcase the capabilities of geomorphons we have calculated the GM for the entire conterminous United States from the 30m/pixel NED DEM. The map shows ten most abundant landforms: flat, peak, ridge, shoulder, spur, slope, hollow, footslope, valley, and pit; a lookup table was used to assign each of the remaining 488 infrequent forms to a morphologically closest mapped form. The result is a unique, never before seen, type of map that clearly shows multiple geomorphic features and indicates the underlying geologic processes. The auto-generation of GM from this high resolution, continental size raster having 168000x104000 cells took 60 hours on a single processor computer. Future applications of such GM include coupling it with a search tool capable of querying the continental-scale GM in order to identify all instances of a given type of local landscape.

Jasiewicz, J.; Stepinski, T. F.

2012-04-01

231

Analysis of the seasonal and interannual evolution of Jakobshavn Isbrae from 2010-2013 using high spatial/temporal resolution DEM and velocity data  

NASA Astrophysics Data System (ADS)

Greenland's large marine-terminating outlet glaciers have displayed marked retreat, speedup, and thinning in recent decades. Jakobshavn Isbrae, one of Greenland's largest outlet glaciers, has retreated ~15 km, accelerated ~150%, and thinned ~200 m since the early 1990s. Here, we present the first comprehensive analysis of high spatial (~2-5 m/px) and temporal (daily-monthly) resolution elevation and velocity data for Jakobshavn from 7/2010 to 7/2013. We have developed an automated processing pipeline using open-source software (Ames Stereo Pipeline, GDAL/OGR, NumPy/SciPy, etc.) to produce orthoimage, digital elevation model (DEM), and surface velocity products from DigitalGlobe WorldView-1/2 stereo imagery (~0.5 m/px, ~17 km swath width). Our timeseries consists of 35 WV DEMs (~2-4 m/px) covering the lower trunks of the main+north branches and fjord, but also extending >110 km inland. We supplement this record with 7 TanDEM-X DEMs (~5 m/px, ~35 km swath width) between 6/2011-9/2012. Elevation data from IceBridge ATM/LVIS, ICESat GLAS, and GPS campaigns provide absolute control data over fixed surfaces (i.e., exposed bedrock). Observed WV DEM offsets are consistent with DigitalGlobe's published value of 5.0 m CE90/LE90 horizontal/vertical accuracy. After DEM co-registration, we observe sub-meter horizontal and vertical absolute accuracy. Velocity data are derived from TerraSAR-X data with 11 day repeat interval. Supplemental velocity data are derived through correlation of high-resolution WV DEM/image data. The contemporaneous DEM and velocity data provide full 3D displacement vectors for each time interval, allowing for the analysis of both Eulerian and Lagrangian elevation change. The lower trunk of Jakobshavn displays significant seasonal velocity variations, with recent rates of ~8 km/yr during winter to >17 km/yr during summer. DEM data show corresponding elevation changes of -30 to -45 m in summer and +15 to +20 m in winter, corresponding to integrated volumes of -1.0 to -1.5 km3 and +0.3 to +0.6 km3 for the lower ~20 km of the main trunk. Further analysis will characterize the upstream propagation of the seasonal elevation change and the relationship with observed strain rates. Seasonal surface mass balance elevation changes are also observed over adjacent grounded, slow-moving (~100 m/yr) regions. The DEM timeseries shows a net interannual thinning trend of -15-20 m/yr for lower Jakobshavn, with decreasing magnitude upstream. This is consistent with long-term altimetry records. Interannual thinning of ~2 m/yr and lateral retreat is also observed for grounded ice sheet margins. These DEM and velocity data capture the timing, magnitude and evolution of dynamic thinning/thickening with unprecedented spatial and temporal resolution. These results also emphasize the importance of dense temporal elevation data when characterizing ice sheet variability and interpreting deviations from long-term records. Similar high-resolution timeseries are available for all major outlet glaciers and ice streams in Greenland and Antarctica. Ultimately, these observations will improve our understanding of outlet glacier behavior, while complementing ongoing efforts to constrain estimates for ice-sheet mass balance and contribution to present/future sea level rise.

Shean, D. E.; Joughin, I. R.; Smith, B. E.; Moratto, Z. M.; Alexandrov, O.; Floricioiu, D.; Morin, P. J.; Porter, C. C.; Beyer, R. A.; Fong, T.

2013-12-01

232

The evaluation of unmanned aerial system-based photogrammetry and terrestrial laser scanning to generate DEMs of agricultural watersheds  

NASA Astrophysics Data System (ADS)

Agricultural watersheds tend to be places of intensive farming activities that permanently modify their microtopography. The surface characteristics of the soil vary depending on the crops that are cultivated in these areas. Agricultural soil microtopography plays an important role in the quantification of runoff and sediment transport because the presence of crops, crop residues, furrows and ridges may impact the direction of water flow. To better assess such phenomena, 3-D reconstructions of high-resolution agricultural watershed topography are essential. Fine-resolution topographic data collection technologies can be used to discern highly detailed elevation variability in these areas. Knowledge of the strengths and weaknesses of existing technologies used for data collection on agricultural watersheds may be helpful in choosing an appropriate technology. This study assesses the suitability of terrestrial laser scanning (TLS) and unmanned aerial system (UAS) photogrammetry for collecting the fine-resolution topographic data required to generate accurate, high-resolution digital elevation models (DEMs) in a small watershed area (12 ha). Because of farming activity, 14 TLS scans (? 25 points m- 2) were collected without using high-definition surveying (HDS) targets, which are generally used to mesh adjacent scans. To evaluate the accuracy of the DEMs created from the TLS scan data, 1098 ground control points (GCPs) were surveyed using a real time kinematic global positioning system (RTK-GPS). Linear regressions were then applied to each DEM to remove vertical errors from the TLS point elevations, errors caused by the non-perpendicularity of the scanner's vertical axis to the local horizontal plane, and errors correlated with the distance to the scanner's position. The scans were then meshed to generate a DEMTLS with a 1 × 1 m spatial resolution. The Agisoft PhotoScan and MicMac software packages were used to process the aerial photographs and generate a DEMPSC (Agisoft PhotoScan) and DEMMCM (MicMac), respectively, with spatial resolutions of 1 × 1 m. Comparing the DEMs with the 1098 GCPs showed that the DEMTLS was the most accurate data product, with a root mean square error (RMSE) of 4.5 cm, followed by the DEMMCM and the DEMPSC, which had RMSE values of 9.0 and 13.9 cm, respectively. The DEMPSC had absolute errors along the border of the study area that ranged from 15.0 to 52.0 cm, indicating the presence of systematic errors. Although the derived DEMMCM was accurate, an error analysis along a transect showed that the errors in the DEMMCM data tended to increase in areas of lower elevation. Compared with TLS, UAS is a promising tool for data collection because of its flexibility and low operational cost. However, improvements are needed in the photogrammetric processing of the aerial photographs to remove non-linear distortions.

Ouédraogo, Mohamar Moussa; Degré, Aurore; Debouche, Charles; Lisein, Jonathan

2014-06-01

233

Automated classifications of topography from DEMs by an unsupervised nested-means algorithm and a three-part geometric signature  

USGS Publications Warehouse

An iterative procedure that implements the classification of continuous topography as a problem in digital image-processing automatically divides an area into categories of surface form; three taxonomic criteria-slope gradient, local convexity, and surface texture-are calculated from a square-grid digital elevation model (DEM). The sequence of programmed operations combines twofold-partitioned maps of the three variables converted to greyscale images, using the mean of each variable as the dividing threshold. To subdivide increasingly subtle topography, grid cells sloping at less than mean gradient of the input DEM are classified by designating mean values of successively lower-sloping subsets of the study area (nested means) as taxonomic thresholds, thereby increasing the number of output categories from the minimum 8 to 12 or 16. Program output is exemplified by 16 topographic types for the world at 1-km spatial resolution (SRTM30 data), the Japanese Islands at 270??m, and part of Hokkaido at 55??m. Because the procedure is unsupervised and reflects frequency distributions of the input variables rather than pre-set criteria, the resulting classes are undefined and must be calibrated empirically by subsequent analysis. Maps of the example classifications reflect physiographic regions, geological structure, and landform as well as slope materials and processes; fine-textured terrain categories tend to correlate with erosional topography or older surfaces, coarse-textured classes with areas of little dissection. In Japan the resulting classes approximate landform types mapped from airphoto analysis, while in the Americas they create map patterns resembling Hammond's terrain types or surface-form classes; SRTM30 output for the United States compares favorably with Fenneman's physical divisions. Experiments are suggested for further developing the method; the Arc/Info AML and the map of terrain classes for the world are available as online downloads. ?? 2006 Elsevier B.V. All rights reserved.

Iwahashi, J.; Pike, R.J.

2007-01-01

234

Helicobacter pylori proteomics by 2-DE/MS, 1-DE-LC/MS and functional data mining.  

PubMed

With its predicted proteome of 1550 proteins (data set Etalon) Helicobacter pylori 26695 represents a perfect model system of medium complexity for investigating basic questions in proteomics. We analyzed urea-solubilized proteins by 2-DE/MS (data set 2-DE) and by 1-DE-LC/MS (Supprot); proteins insoluble in 9 M urea but solubilized by SDS (Pellet); proteins precipitating in the Sephadex layer at the application side of IEF (Sephadex) by 1-DE-LC/MS; and proteins precipitating close to the application side within the IEF gel by LC/MS (Startline). The experimental proteomics data of H. pylori comprising 567 proteins (protein coverage: 36.6%) were stored in the Proteome Database System for Microbial Research (http://www.mpiib-berlin.mpg.de/2D-PAGE/), which gives access to raw mass spectra (MALDI-TOF/TOF) in T2D format, as well as to text files of peak lists. For data mining the protein mapping and comparison tool PROMPT (http://webclu.bio.wzw.tum.de/prompt/) was used. The percentage of proteins with transmembrane regions, relative to all proteins detected, was 0, 0.2, 0, 0.5, 3.8 and 6.3% for 2-DE, Supprot, Startline, Sephadex, Pellet, and Etalon, respectively. 2-DE does not separate membrane proteins because they are insoluble in 9 M urea/70 mM DTT and 2% CHAPS. SDS solubilizes a considerable portion of the urea-insoluble proteins and makes them accessible for separation by SDS-PAGE and LC. The 2-DE/MS analysis with urea-solubilized proteins and the 1-DE-LC/MS analysis with the urea-insoluble protein fraction (Pellet) are complementary procedures in the pursuit of a complete proteome analysis. Access to the PROMPT-generated diagrams in the Proteome Database allows the mining of experimental data with respect to other functional aspects. PMID:19941309

Jungblut, Peter R; Schiele, Franziska; Zimny-Arndt, Ursula; Ackermann, Renate; Schmid, Monika; Lange, Sabine; Stein, Robert; Pleissner, Klaus-Peter

2010-01-01

235

Comparative FEM and DEM modeling of basement-involved thrust structures, with application to Sheep Mountain, Greybull area, Wyoming  

NASA Astrophysics Data System (ADS)

Basement-involved fold and thrust systems have been widely studied in several locations, through field and seismic investigations. However, our understanding of the geometries of the faults that drive folding, and the mechanical conditions within the resulting folds, is still limited. Simulations run using the finite element and discrete element methods have great potential to help determine the mechanical evolution of structures at all scales. Both methods have been employed to explore the structural evolution of the Laramide-age Sheep Mountain anticline, located in the eastern Bighorn Basin of Wyoming. Both sets of simulations are constrained by experimental and well log data, and use the same size model domain and mechanical stratigraphy. The underlying basement-sediment boundary was deformed by a set of prescribed displacements. The results of the two simulations are geometrically similar, and match previous field-based interpretations of the Sheep Mountain fold to the first order. Stresses calculated by the two methods were also very similar, thus verifying the mechanical comparison. Differences in the geometric details, however, provide important perspectives on the capabilities of the two methods. For example, the major faults producing the Sheep Mountain fold develop slightly higher dips in the DEM simulation than the FEM simulation, yielding a better match with published interpretations. The crest of the anticline is characterized by distributed thinning of shallow strata in the FEM simulation, and by local extensional faulting in the DEM simulation. Neither simulation reproduced the north-south fold splay observed in the field, suggesting that this minor feature results from preexisting structure or 3D effects not modeled here.

Zhang, Jie; Morgan, Julia K.; Gray, Gary G.; Harkins, Nathan W.; Sanz, Pablo F.; Chikichev, Ivan

2013-11-01

236

Automated classifications of topography from DEMs by an unsupervised nested-means algorithm and a three-part geometric signature  

NASA Astrophysics Data System (ADS)

An iterative procedure that implements the classification of continuous topography as a problem in digital image-processing automatically divides an area into categories of surface form; three taxonomic criteria-slope gradient, local convexity, and surface texture-are calculated from a square-grid digital elevation model (DEM). The sequence of programmed operations combines twofold-partitioned maps of the three variables converted to greyscale images, using the mean of each variable as the dividing threshold. To subdivide increasingly subtle topography, grid cells sloping at less than mean gradient of the input DEM are classified by designating mean values of successively lower-sloping subsets of the study area (nested means) as taxonomic thresholds, thereby increasing the number of output categories from the minimum 8 to 12 or 16. Program output is exemplified by 16 topographic types for the world at 1-km spatial resolution (SRTM30 data), the Japanese Islands at 270 m, and part of Hokkaido at 55 m. Because the procedure is unsupervised and reflects frequency distributions of the input variables rather than pre-set criteria, the resulting classes are undefined and must be calibrated empirically by subsequent analysis. Maps of the example classifications reflect physiographic regions, geological structure, and landform as well as slope materials and processes; fine-textured terrain categories tend to correlate with erosional topography or older surfaces, coarse-textured classes with areas of little dissection. In Japan the resulting classes approximate landform types mapped from airphoto analysis, while in the Americas they create map patterns resembling Hammond's terrain types or surface-form classes; SRTM30 output for the United States compares favorably with Fenneman's physical divisions. Experiments are suggested for further developing the method; the Arc/Info AML and the map of terrain classes for the world are available as online downloads.

Iwahashi, Junko; Pike, Richard J.

2007-05-01

237

Estimation and analysis of land surface water and heat fluxes in mountain-plain area based on remote sensing and DEM  

Microsoft Academic Search

The income and expenses status of water along with heat on land surface determine the form and evolvement of environment to a great extent. This paper focus on the topic of estimation and analysis of land surface water and heat fluxes in mountain-plain area based on remote sensing and DEM, selecting Sunan Mountain and Zhangye Plain in China as a

Hequn Yang; Yong Liua; Yinming Yang; Cong Zhang

2009-01-01

238

Channel planform geometry and slopes from freely available high-spatial resolution imagery and DEM fusion: Implications for channel width scalings, erosion proxies,  

E-print Network

Channel planform geometry and slopes from freely available high-spatial resolution imagery and DEM fusion: Implications for channel width scalings, erosion proxies, and fluvial signatures in tectonicallyGeom) to extract continuous channel width and centerline datasets for single-thread channels using freely available

Bookhagen, Bodo

239

Surface lowering and flow speed decrease of Khumbu Glacier detected from GPS survey and ASTER-DEM, in Nepal Himalayas between 1995 and 2004  

Microsoft Academic Search

Four characteristic areas in the debris-covered ablation zone have been surveyed intermittently on Khumbu Glacier, Nepal Himalayas since 1978. We carried out ground survey by differential GPS (DGPS) in 2004 to clarify changes in surface elevation and flow speeds of the glacier. Surface lowerings are obtained by comparison of digital elevation model (DEM, 60 m grid size), which are generated

T. Nuimura; K. Fukui; K. Asahi; K. Fujita; Y. Ageta

2006-01-01

240

Assessment of a Near-Global 30-meter Resolution DEM Derived from the Publicly Available SRTM Data Set for Use in Orthorectification of Satellite SAR Imagery  

NASA Astrophysics Data System (ADS)

The Shuttle Radar Topography Mission (SRTM) utilized an interferometric synthetic aperture radar (InSAR) flown onboard the space shuttle Endeavour to obtain high resolution elevation data of Earth's land surface. Virtually all land surface between +/- 60 degrees latitude was mapped. Regions within these bounds contain some data gaps but this represents less than 0.2 % of the coverage. Standard publicly-available data sets from SRTM include a 3 arc-second (~90 meter) resolution Digital Elevation Model (DEM) with absolute average global vertical accuracy of approximately 4 to 5 meters. A 1 arc-second (~30 meter) resolution DEM has also been developed, but only the portion of the data set covering the United States is publicly available. The finished version of these products has been edited for pixel-level errors and delineation of coastlines and water bodies, although some data voids are still present. Utilizing such DEMs of appropriate resolution in a common framework with satellite synthetic aperture radar (SAR) data allows robust ortho-rectification and geo-referencing of the SAR data sets. We have derived a 1 arc-second resolution DEM over the entire domain of the SRTM coverage using a 3- dimensional interpolation scheme applied to the 3 arc-second SRTM DEM. Development of this product involves (1) translation of SRTM products into the WGS84 datum, (2) interpolation of the lower resolution DEMs to 1 arc- second, and (3) assembly of the global-scale 1 arc-second DEM. We assess effectiveness of this interpolation scheme through comparative statistical analysis of the 3 arc-second finished product, the 1 arc-second finished product, and the 1 arc-second interpolated product over selected test regions within the USA where all products are available. Comparisons are also made to standard GTOPO30 products for regions inside and outside of the USA. Comparisons are presented for regions representative of gentle and complex terrain. Ortho-rectification of SAR data such as those obtained from the Japanese Earth Resources Satellite (JERS) and ALOS PALSAR allows for an accurate representation of these data, providing crucial information accounting for effects of topography on geophysical retrievals. This work was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under contract to the National Aeronautics and Space Administration.

McDonald, K. C.; Chapman, B.; Podest, E.; Jimenez, A.

2007-12-01

241

[Development of the behaviour observation scale for psychomotor therapy for elderly people with dementia (BPMT-dem). Reliability and concurrent validity].  

PubMed

This article describes the development of the Behaviour observation scale for Psychomotor Therapy for elderly people with dementia (BPMT-dem). This scale was developed in the late 1980s in order to evaluate the effect of psychomotor group therapy on the cognitive, social, and emotional functioning of elderly people with dementia within the therapy situation. The currently described research investigates inter-assessor reliability and internal consistency of the ten subscales (such as memory, orientation, contact with others, initiative, anxious behaviour, aggressive behaviour) and three domains, as well as the scale's correlation with other observation scales (concurrent validity) in two different patient groups. The first group consisted of clients receiving psychomotor therapy in a nursing home or a psychiatric hospital (N = 130). Inter-assessor reliability (Cohen's kappa) varied between 0.27 and 1.00 the internal consistency of the subscales (Cronbach's alpha) was calculated between 0.46 and 0.86, and that of the domains between 0.76 and 0.81. Based on the findings of this study 15 of the original 88 items were removed, 5 items were moved to other subscales and the text of 2 items was changed. Next, the subscale internal consistency and concurrent validity of this modified (73-item version) BPMT-dem was investigated in a group of 41 elderly participating in a support programme in meeting centres for elderly people with dementia and their caregivers. Cronbach's alpha for the subscales in this study was calculated between 0.47 and 0.86. To determine concurrent validity, the BPMT-dem was compared with (subscales of) the Assessment Scale for Elderly Patients (ASEP), Behavioural assessment for Intramural Psychogeriatrics (BIP), Brief Cognitive Rating Scale (BCRS) and the Cornell Scale for Depression in Dementia. Correlations with related BPMT-dem subscales varied between 0.38 and 0.75. The inter-assessor reliability and concurrent validity of the 73-item version of the BPMT-dem are satisfactory. The internal consistency of 6 subscales is sufficient, and recommendations are proposed to improve the consistency of the remaining subscales. Further research to test the unidimensionality and scalability of the subscales of the BPMT-dem, as well as the effect of the recommended reformulation and removal of items, is recommended. Before the instrument can be used in actual practice, the psychometric qualities of the BPMT-dem73 need to be studied in a larger and in terms of severity of dementia more heterogeneous study sample, so that statements can also be made on which norms to use in various subgroups of elderly with dementia. PMID:17605286

Lauriks, S; Dröes, R M

2007-05-01

242

Estimation of mass change rates of surge-type glaciers in the Karakoram derived from TanDEM-X and SRTM Digital Elevation Models  

NASA Astrophysics Data System (ADS)

Glaciers in the Karakoram region exhibit stable and advancing termini positions accompanied by less negative or even positive surface mass balances in comparison to the adjacent Greater Himalaya Range and the Hindu Kush mountains. Moreover, a large number of surge-type glaciers is found in the Karakoram. During the active phase of a surge, ice masses are shifted from the reservoir area towards the receiving area of a glacier. Remote sensing based methods provide various possibilities to identify surge-type glaciers (termini position changes, surface velocity variations, mass changes), where in-situ measurements are hardly available. The present study focuses on glacier mass changes in the Karakoram between 2000 and 2013 derived from DEM differencing. We used the C-band SRTM DEM (February, 2000) and high resolution TanDEM-X data (2011-2013). Due to quasi bi-static image acquisitions, TanDEM-X data is very suitable for interferometric elevation generation minimizing decorrelation impacts. However, influences of different penetration depths of X- and C-band have to be considered. We quantified glacier volume and mass changes for the central part of the Karakoram for a twelve year period. For a surge-type glacier in the Shimshal Valley we observed a mass relocation of 2.96±2.52 m/a w.e. close to its snout between 2000 and 2012. Further case studies will be presented including annual mass changes (2011-2013) determined using repeat TanDEM-X acquisitions. In addition to interannual surface velocity changes, mass change observations can help to obverse the propagation of the surge front down-glacier and quantify the relocation of mass during an active surge phase.

Rankl, Melanie; Braun, Matthias; Vijay, Saurabh

2014-05-01

243

Site-specific assessment of the rockfall and the rock block volume distribution relations, using a LIDAR generated DEM  

NASA Astrophysics Data System (ADS)

The quantification of the rockfall hazard and, in particular of the rockfall propagation, requires information on the expected probability or frequency of rockfalls of a given magnitude (size), usually in the form of magnitude-frequency M-F relations. Two kinds of relations are needed. The first one characterises the rockfall masses that can be potentially detached from the slope face giving information on the volume distribution of rockfalls. From now on, this will be referred to as potential rockfall volume distribution VDR. For fragmental rockfalls, the evaluation of the VDR can be a first step towards the temporal M-F, The second one characterises the volume distribution of the rock blocks that result from the disintegration of the previous rockfall masses due to impact with the ground. This one will be referred to as rock block volume distribution VDB. In this work we present two analytical procedures which are independent from the existence of empirical data, for: (i) The calculation of the potential VDR that refers to big volumes with low probability of occurrence. This is realised by detection of the kinematically unstable surfaces on a DEM and on orthophotos, and calculation of the volumes that correspond to them. The basic assumptions here describing a conservative scenario of very low probability are: (a) the rockfall mass is detached entirely at a single rockfall event, without taking into account that smaller successive failures are possible instead; (b) all discontinuity sets are present everywhere in the slope and have infinite persistence; and (c) big stepped-path failures are possible. (ii) The assessment of the in-situ rock blocks volume distribution on the slope face, VDB, by calculation of the volume of the prisms which are formed by the intersection of the existing discontinuity sets and are kinematically unstable. This is also based on data obtained by DEM analysis. A high-resolution DEM obtained by Lidar is used. Both procedures are presented though an application example at the country of Andorra and in particular at the chute of Forat Negre. The results from the first procedure indicate that it is kinematically possible to have mobilised volumes of some thousands of cubic meters although the probability of generating large volumes is low. The VDR for big volume events was well fitted by a power-law equal to -0.5. The VDB from the second procedure, assuming three intersection types within the discontinuity network and two extreme cases of discontinuity persistence, was also found to follow a power-law, with exponent -1.3. The comparison with field data collected by past studies in the same area indicates that in reality, the discontinuities have a very high persistence and that considering only their visible trace length is very conservative.

Mavrouli, Olga; Corominas, Jordi; Jaboyedoff, Michel

2014-05-01

244

Topographic changes due to the 2008 Mw 7.9 Wenchuan earthquake as revealed by the differential DEM method  

NASA Astrophysics Data System (ADS)

Landscape evolution in active orogenic regions is inevitably affected by the repeated strong earthquakes triggered by the corresponding active faults. However, the lack of adequate methods for the documentation and monitoring of mountain-building processes has resulted in a shortage of quantitative estimates of orogenic and eroded volumes. A strong earthquake and its associated co-seismic landslides represent a sudden pulse in landscape evolution in tectonically active areas. The 2008 Mw 7.9 Wenchuan earthquake dramatically modified the topography of the Longmen Shan region. Based on topographic data before the earthquake and stereo pairs of post-earthquake remote sensing imagery, we derived pre- and post-earthquake DEMs (digital elevation models) of the three regions along the Longmen Shan Thrust Belt. By comparing the geomorphic features before and after the earthquake, we find that the Wenchuan earthquake smoothed the steep relief and caused a co-seismic uplift of the Longmen Shan region. The medium-relief regions increased; however, the high-relief regions decreased, indicating that the local relief is controlled by repeated strong earthquakes. The changed slope aspect indicates that the formation and modification of the east- and west-facing slopes are controlled by tectonic events in the Longmen Shan region, which might be associated with the regional stress field. However, the unchanged aspects of other slopes might be controlled by long-term erosion rather than tectonic events. The topographic changes, landslide volume and co-seismic uplift indicate that the greatest seismically induced denudation occurred in association with a thrust faulting mechanism and low-angle fault geometry. Our findings reveal that the local relief has been shaped by the localized, seismically induced high rate of denudation within the plateau margins, and that the formation of local relief is also related to tectonic events, especially the events that have occurred on low-angle faults. This study also indicates that the multi-temporal DEM differential method is valuable in detecting seismically induced topographic change.

Ren, Zhikun; Zhang, Zhuqi; Dai, Fuchu; Yin, Jinhui; Zhang, Huiping

2014-07-01

245

Developing sub 5-m LiDAR DEMs for forested sections of the Alpine and Hope faults, South Island, New Zealand: Implications for structural interpretations  

NASA Astrophysics Data System (ADS)

Kilometre-wide airborne light detection and ranging (LiDAR) surveys were collected along portions of the Alpine and Hope faults in New Zealand to assess the potential for generating sub 5-m bare earth digital elevation models (DEMs) from ground return data in areas of dense rainforest (bush) cover as an aid to mapping these faults. The 34-km long Franz-Whataroa LiDAR survey was flown along the densely-vegetated central-most portion of the transpressive Alpine Fault. Six closely spaced flight lines (200 m apart) yielded survey coverage with double overlap of swath collection, which was considered necessary due to the low density of ground returns (0.16 m-2 or a point every 6 m2) under mature West Coast podocarp-broadleaf rainforest. This average point spacing (˜2.5 m) allowed for the generation of a robust, high quality 3-m bare earth DEM. The DEM confirmed the zigzagged form of the surface trace of the Alpine Fault in this area, originally recognised by Norris and Cooper (1995, 1997) and highlights that the surface strike variations are more variant than previously mapped. The 29-km long Hurunui-Hope LiDAR survey was flown east of the Main Divide of the Southern Alps along the dextral-slip Hope Fault, where the terrain is characterised by lower rainfall and more open beech forest. Flight line spacings of ˜275 m were used to generate a DEM from the ground return data. The average ground return values under beech forest were 0.27 m-2 and yielded an estimated cell size suitable for a 2-m DEM. In both cases the LiDAR revealed unprecedented views of the surface geomorphology of these active faults. Lessons learned from our survey methodologies can be employed to plan cost-effective, high-gain airborne surveys to yield bare earth DEMs underneath vegetated terrain and multi-storeyed canopies from densely forested environments across New Zealand and worldwide.

Langridge, R. M.; Ries, W. F.; Farrier, T.; Barth, N. C.; Khajavi, N.; De Pascale, G. P.

2014-07-01

246

Numerical Modelling of the Anisotropic Mechanical Behaviour of Opalinus Clay at the Laboratory-Scale Using FEM/DEM  

NASA Astrophysics Data System (ADS)

The Opalinus Clay (OPA) is an argillaceous rock formation selected to host a deep geologic repository for high-level nuclear waste in Switzerland. It has been shown that the excavation damaged zone (EDZ) in this formation is heavily affected by the anisotropic mechanical response of the material related to the presence of bedding planes. In this context, the purpose of this study is twofold: (i) to illustrate the new developments that have been introduced into the combined finite-discrete element method (FEM/DEM) to model layered materials and (ii) to demonstrate the effectiveness of this new modelling approach in simulating the short-term mechanical response of OPA at the laboratory-scale. A transversely isotropic elastic constitutive law is implemented to account for the anisotropic elastic modulus, while a procedure to incorporate a distribution of preferentially oriented defects is devised to capture the anisotropic strength. Laboratory results of indirect tensile tests and uniaxial compression tests are used to calibrate the numerical model. Emergent strength and deformation properties, together with the simulated damage mechanisms, are shown to be in strong agreement with experimental observations. Subsequently, the calibrated model is validated by investigating the effect of confinement and the influence of the loading angle with respect to the specimen anisotropy. Simulated fracture patterns are discussed in the context of the theory of brittle rock failure and analyzed with reference to the EDZ formation mechanisms observed at the Mont Terri Underground Research Laboratory.

Lisjak, Andrea; Tatone, Bryan S. A.; Grasselli, Giovanni; Vietor, Tim

2014-01-01

247

Optimization of operating conditions in a high-shear mixer using dem model: determination of optimal fill level.  

PubMed

For the purpose of evaluating optimal fill level of starting materials in a high-shear mixer, discrete element method (DEM) simulation was conducted to visualize kinetic status between particles. The simulation results obtained by changing fill levels were used to determine solid fraction of particles, particle velocity, particle velocity vector, and kinetic energy and discuss the flow pattern. Optimal fill level was obtained from the information on these matters. It was pointed out that understanding the kinetic energy between particles in an agitating vessel was effective in determining the optimal fill level. Granulation experiment was conducted to validate the optimal fill level obtained by the simulation, confirming the good agreement between these two results. It was pointed out that determination of kinetic energy between particles through the simulation was effective in obtaining an index of the kinetic status of particles. Further, it was confirmed that the simulation could provide more information than conventional granulation experiments could provide and also helpful in optimizing the operating conditions. PMID:12499588

Terashita, Keijiro; Nishimura, Takehiko; Natsuyama, Susumu

2002-12-01

248

Mass changes of outlet glaciers along the Nordensjköld Coast, northern Antarctic Peninsula, based on TanDEM-X satellite measurements  

NASA Astrophysics Data System (ADS)

analyzed volume change and mass balance of outlet glaciers of the northern Antarctic Peninsula over the period 2011 to 2013, using topographic data of high vertical accuracy and great spatial detail, acquired by bistatic radar interferometry of the TanDEM-X/TerraSAR-X satellite formation. The study area includes glaciers draining into the Larsen-A, Larsen Inlet, and Prince-Gustav-Channel embayments. After collapse of buttressing ice shelves in 1995 the glaciers became tidewater calving glaciers and accelerated, resulting in increased ice export. Downwasting of most glaciers is going on, but at reduced rates compared to previous years in accordance with deceleration of ice flow. The rate of mass depletion is 4.2 ± 0.4 Gt a-1, with the largest contribution by Drygalski Glacier amounting to 2.2 ± 0.2 Gt a-1. On the technological side, the investigations demonstrate the capability of satellite-borne single-pass radar interferometry as a new tool for accurate and detailed monitoring of glacier volume change.

Rott, Helmut; Floricioiu, Dana; Wuite, Jan; Scheiblauer, Stefan; Nagler, Thomas; Kern, Michael

2014-11-01

249

DEMS study of gas evolution at thick graphite electrodes for lithium-ion batteries: the effect of ?-butyrolactone  

NASA Astrophysics Data System (ADS)

Differential electrochemical mass spectrometry (DEMS) was used to study the reductive decomposition of an electrolyte based on ethylene carbonate/dimethyl carbonate (EC/DMC), as well as the formation of a solid electrolyte interphase (SEI) in this electrolyte, at thick (75-100 ?m) porous graphite composite electrodes. A number of graphite electrodes differing in their electrochemical lithium intercalation properties were investigated in potential-sweep experiments. They proved to be similar with respect to the evolution of ethylene and hydrogen gas during the first two charge/discharge cycles. Due to an incomplete coulombic conversion, a high irreversible capacity, as well as slow diffusion kinetics and an enhanced ohmic resistance of the electrodes, SEI formation on these thick electrodes was not yet complete after the first charge/discharge cycle. Undesired gas evolution can be reduced by adding ?-butyrolactone (GBL) as an electrolyte co-solvent. The amount of ethylene and hydrogen gas evolved decreases with increasing percentages of GBL in an EC/DMC electrolyte, indicating that the SEI layer is built up from GBL rather than from EC decomposition products.

Lanz, Martin; Novák, Petr

250

Zur Unterscheidung von Thamnobryum subserratum (Hook. ex Harv.) Nog. & Z. Iwats. und Thamnobryum neckeroides (Hook.)  

Microsoft Academic Search

Zusammenfassung: Die Unterschiede zwischen den jüngst in Europa nachgewiesenen Thamnobryum subserratum, welches unter diesem Namen aus Japan und als Th. allegheniense aus Nordamerika bekannt ist, sowie dem zuvor nur aus dem westlichen Nordamerika bekannten Thamnobryum neckeroides und dem heimischen Thamnobryum alopecurum sind nach der Literatur zusammengestellt und an Hand von Herbarmaterial illustriert. Die Variabilität von Thamnobryum alopecurum ist diskutiert. Abstract:

E. Lawton; Jan-Peter Frahm

251

Validating the DemTect with 18-Fluoro-2DeoxyGlucose Positron Emission Tomography as a Sensitive Neuropsychological Screening Test for Early Alzheimer Disease in Patients of a Memory Clinic  

Microsoft Academic Search

Objectives: The first study to validate the diagnostic value of the DemTect, a short neuropsychological screening test for dementia (8–10 min), using 18-fluoro-2-deoxy-glucose positron emission tomography (FDG-PET) in patients of a memory clinic. Methods: DemTect results were compared to the clinical diagnosis and to FDG-PET as a reference method for the early in vivo detection of Alzheimer’s disease (AD). Results:

Armin Scheurich; Matthias J. Müller; Thomas Siessmeier; Peter Bartenstein; Lutz G. Schmidt; Andreas Fellgiebel

2005-01-01

252

Coastal flood risk analysis using landsat-7 ETM+ imagery and SRTM DEM: a case study of Izmir, Turkey.  

PubMed

The Intergovernmental Panel on Climate Change (IPCC) reports an acceleration of the global mean sea-level rise (MSLR) in the twentieth century in response to global climate change. If this acceleration remains constant, then some coastal areas are most likely to be inundated by the year 2100. The ability to identify the differential vulnerability of coastlines to future inundation hazards as result of global climate change is necessary for timely actions to be taken. Yildiz et al. (Journal of Mapping, 17, 1-75, 2003) reported that the local MSLR in the city of Izmir rose at a rate of 6.8 +/- 0.9 mm year(-1) between 1984 and 2002. In this study, the spatial distribution of the coastal inundation hazards of Izmir region was determined using not only land-use and land-cover (LULC) types derived from the maximum likelihood classification of Landsat-7 Enhanced Thematic Mapper Plus (ETM+) multi-spectral image set but also the classification of the digital elevation model (DEM) acquired by the shuttle radar topography mission (SRTM). Coastal areas with elevations of 2 and 5 m above mean sea-level vulnerable to inundation were found to cover 2.1 and 3.7% of the study region (6,107 km(2)), respectively. Our findings revealed that Menemen plain along Gediz river, and the settlements of Karsiyaka, Alacati, Aliaga, Candarli and Selcuk are at high risk in order of decreasing vulnerability to permanent and episodic inundation by 2100 under the high MSLR scenarios of 20 to 50 mm year(-1). PMID:17171268

Demirkesen, A C; Evrendilek, F; Berberoglu, S; Kilic, S

2007-08-01

253

Yaquina Bay Topobathy DEM  

EPA Science Inventory

The U.S.EPA contracted with the U.S.ACE to obtain intertidal and subtidal bathymetric soundings of Yaquina Bay between Poole Slough and the South Beach Marina in 2002. These data were compiled with U.S.ACE subtidal soundings from 1999, 1998, 2000 and National Ocean Service soundi...

254

Predict Dem Bones!  

ERIC Educational Resources Information Center

A detailed analysis and computer-based solution to a puzzle addressing the arrangement of dominoes on a grid is presented. The problem is one used in a college-level data structures or algorithms course. The solution uses backtracking to generate all possible answers. Details of the use of backtracking and techniques for mapping abstract problems…

Gray, John S.

1994-01-01

255

Activity of Nyiragongo and Nyamulagira Volcanoes (Dem. Rep. of Congo) Revealed Using Geological, Geophysical and InSAR data  

NASA Astrophysics Data System (ADS)

Ground-based monitoring of active volcanoes in Africa can be problematic due to political instabilities, safety issues and poor accessibility. Remote-sensing techniques such as Differential Interferometric Synthetic Aperture Radar (DInSAR, more commonly InSAR), are therefore very useful and provide robust observational tools for natural hazard assessment, regardless of local conditions. Nyiragongo and Nyamulagira volcanoes (which experienced nine eruptions from December 1996 to January 2010) are located in the western branch of the East African Rift (Virunga Volcanic Province, North Kivu, Dem. Rep. of Congo). InSAR has recorded ground displacements related to most of the tectonic and volcanic events that have occurred since 1996 using SAR images from the JERS, ERS-1/2, ENVISAT, RADARSAT-1, RADARSAT-2 and ALOS satellites. This database provides excellent spatial and temporal resolution of deformation, leading to insights into tectonic and volcanic processes. Loss of coherence within the SAR signal due to rapid-changing equatorial vegetation hampers the use of InSAR as a volcano-tectonic monitoring tool. We partially overcome this limitation using 1) a large number of SAR images, including about 150 ENVISAT and more than 100 RADARSAT-1 images, 2) short repeat times of 24 and 35 days for RADARSAT-1 and ENVISAT, respectively, and 3) satellites with longer wavelengths, such as JERS and ALOS. Using a large dataset combining short revisit time SAR images significantly increases the chances of producing interferograms with good coherence. A longer wavelength radar signal better penetrates vegetation cover, also increasing coherence. Furthermore, useful data were retrieved in low-coherence areas by applying the “StaMPS” (Stanford Method for Persistent Scatterers) method, which combines a small baseline and persistent scatterers approach, to our largest SAR datasets. Using several look angles from both ascending and descending orbital tracks, we were able to characterize the 3D ground displacement field. A 3D Mixed Boundary Element Method is used to infer geometry and physical characteristics of the sources controlling volcanic unrest and tectonic activity. In addition, we combined our InSAR database with other available data, such as seismicity from a network maintained since 2002 and results from geological and geophysical surveys from the volcanoes, to better constrain source processes. The improved understanding and constraints on volcanic processes in the North Kivu area made possible by this multidisciplinary approach will be highlighted with a few case studies of recent volcanic activity.

Wauthier, C.; Cayol, V.; Hooper, A.; Kervyn, F.; Marinkovic, P.; D'Oreye, N.; Poland, M. P.

2010-12-01

256

Intercomparison of DEM-based approaches for the identification of flood-prone areas in different geomorphologic and climatic conditions  

NASA Astrophysics Data System (ADS)

Floods represent the most critical natural hazard for many countries and their frequency appears to be increasing in recent times. The legal constraints of public administrators and the growing interest of private companies (e.g., insurance companies) in identifying the areas exposed to the flood risk, is determining the necessity of developing new tools for the risk classification over large areas. Nowadays, among the numerous hydrologic and hydraulic methods regularly used for practical applications, 2-D hydraulic modeling represents the most accurate approach for deriving detailed inundation maps. Nevertheless, data requirement for these modeling approaches is certainly onerous, limiting their applicability over large areas. On this issue, the terrain morphology may provide an extraordinary amount of information useful to detect areas that are particularly prone to serious flooding. In the present work, we compare the reliability of different DEM-derived quantitative morphologic descriptors in characterizing the relationships between geomorphic attributes and flood exposure. The tests are carried out using techniques of pattern classification, such as linear binary classifiers (Degiorgis et al., 2012), whose ability is evaluated through performance measures. Simple and composed morphologic features are taken into account. The morphological features are: the upslope contributing area (A), the local slope (S), the length of the path that hydrologically connects the location under exam to the nearest element of the drainage network (D), the difference in elevation between the cell under exam and the final point of the same path (H), the curvature (downtriangle2H). In addition to the mentioned features, the study takes into consideration a number of composed indices, such as: the modified topographic index (Manfreda et al., 2011), the downslope index (DI) proposed by Hjerdt et al. (2004), the ratio between the elevation difference H and the distance to the network D, and other indices. Each binary classifier is applied in several catchments in order to verify the reproducibility of the procedures in different geomorphologic, climatic and hydrologic conditions. The study explores the use of these procedures in gauged river basins located in Italy and in an ungauged basin located in Africa. References Degiorgis, M., G. Gnecco, S. Gorni, G. Roth, M. Sanguineti, A.C. Taramasso, 2012. Classifiers for the detection of flood-prone areas using remote sensed elevation data, J. Hydrol., 470-471, 302-315. Hjerdt, K. N., J.J. McDonnell, J. Seibert, A. Rodhe, A new topographic index to quantify downslope controls on local drainage, Water Resour. Res., 40, W05602, 2004. Manfreda, S., M. Di Leo, A. Sole, Detection of Flood Prone Areas using Digital Elevation Models, J. Hydrol. Eng., 16(10), 781-790, 2011.

Samela, Caterina; Nardi, Fernando; Grimaldi, Salvatore; De Paola, Francesco; Sole, Aurelia; Manfreda, Salvatore

2014-05-01

257

Study of Morphologic Change in Poyang Lake Basin Caused by Sand Dredging Using Multi-temporal Landsat Images and DEMs  

NASA Astrophysics Data System (ADS)

Sand dredging has been practiced in rivers, lakes, harbours and coastal areas in recent years in China mostly because of demand from construction industry as building material. Sand dredging has disturbed aquatic ecosystems by affecting hydrological processes, increasing content of suspended sediments and reducing water clarity. Poyang Lake, connecting with Yangtze River in the lower reaches of the Yangtze River, is the largest fresh water lake in China. Sand dredging in Poyang Lake has been intensified since 2001 because such practice was banned in Yangtze River and profitable. In this study, the morphologic change caused by sand dredging in Poyang Lake basin was analysed by overlaying two DEMs acquired in 1952 and 2010 respectively. Since the reflectance of middle infrared band for sand dredging vessel is much higher than that of water surface, sand dredging vessels were showed as isolated grey points and can be counted in the middle infrared band in 12 Landsat images acquired in flooding season during 2000~2010. Another two Landsat images (with low water level before 2000 and after 2010) were used to evaluate the morphologic change by comparing inundation extent and shoreline shape. The following results was obtained: (1) vessels for sand dredging are mainly distributed in the north of Poyang Lake before 2007, but the dredging area was enlarged to the central region and even to Gan River; (2) sand dredging area reached to about 260.4 km2 and is mainly distributed in the north of Songmen Mountain and has been enlarged to central of Poyang Lake from the distribution of sand vessels since 2007. Sand dredged from Poyang Lake was about 1.99 × 109 m3 or 2448 Mt assuming sediment bulk density of 1.23 t m-3. It means that the magnitude of sand mining during 2001-2010 is almost ten times of sand depositions in Poyang Lake during 1955-2010; (3) Sand dredging in Poyang Lake has alternated the lake capacity and discharge section area, some of the watercourse in the northern channel was enlarged by more than 1 km when in low lake level. This study is useful to understand the change of hydrological system, especially the drying up trend in Poyang Lake in recent autumns and winters.

Qi, S.; Zhang, X.; Wang, D.; Zhu, J.; Fang, C.

2014-11-01

258

Tracking and evolution of irrigation triggered active landslides by multi-source high resolution DEM: The Jiaojiacun landslide group of Heifangtai (Northwest of China)  

NASA Astrophysics Data System (ADS)

The construction of three large hydropower stations, i.e. Liujia, Yanguo and Bapan, resulted in the immigration of the impacted people to Heifangtai from 1960s. To support the living and farming of the immigrated people, a large amount of water has been pumped from the Yellow River to Heifangtai, which has changed the former underground water budget and led to 111 landslides from 1968 in this area. To reveal the deformation process of landslides in Heifangtai, a quantitative deformation analysis model of landslide based on multi-source DEM data is established using four periods of topographic maps obtained in 1970, 2001, 2010 and 2013 respectively, including two 1:10000 topographic maps and two 1:1000 data acquired from 3D Laser Scanner. The whole study area was divided into two sections based on the two distinct kinds of landslide patterns. The selected morphometric parameters, residual topographic surface and surface roughness, extracted from three typical landslides, and the statistical analysis (Box-plot diagrams) of the temporal variations of these parameters, allowed the reconstruction and tracking of these landslides. We monitored the changing of landslide boundaries, average vertical and horizontal displacement rates and zones of uplift and subsidence. The volumes of removed and/or accumulated material were estimated as well. We can then demonstrate the kinematics of landslides based on information from high-resolution DEM, and the changing table of underground water, ring-shear test and soil-water characteristic curve referenced from other researchers. The results provide a new insight on the use of multi-source high resolution DEM in the monitoring of irrigation-triggered landslides.

Zeng, Runqiang; Meng, Xingmin; Wang, Siyuan; Chen, Guan; Lee, Yajun; Zhang, Yi

2014-05-01

259

Transparente protokollierbare Kommunikation zwischen Funktionen kognitiver Systeme  

NASA Astrophysics Data System (ADS)

In kognitiven Systemen werden komplexe Entscheidungen getroffen, die ein umfassendes Umfeldverständnis erfordern. Technische Realisierungen sind meist datenintensiv und bestehen aus vielen Teilfunktionen. Um solche Systeme zu überwachen und neue Funktionen zu testen ist eine transparente und verfolgbare Kommunikation notwendig. Dieser Beitrag präsentiert einen datenzentrierten Ansatz zur Kommunikation und liefert eine Methode um alle Kommunikationsbeziehungen zu beobachten und ganzheitlich aufzuzeichnen. Ausgewählte Anwendungen demonstrieren die erzielten Ergebnisse.

Goebl, Matthias; Färber, Georg

260

Bilder als Vermittler zwischen Krebsforschung und Mathematik  

E-print Network

. The intestinal colon consists of about 400 billion cells intestinal tract (cell death) Functional Organization #12;1/7/2010 5 ... appr. 60% of the whole Eight ways to describe the role of cyclin Image from Chemical reactions Image from: The Systems Biology Graphical Notation, Nature Biotechnology, Vol 27, Nr 8

Rostock, Universität

261

Celestial architecture.  

E-print Network

??ABBILDUNGEN: nur in PRINTAUSGABE! Die vorliegende Studie betrachtet den komplexen, vielfältigen Dialog im Westlichen Trans-Himalaya, der zwischen der neuen buddhistischen Elite, dem Dro-Can in Ladakh,… (more)

Papa-Kalantari, Christiane

2008-01-01

262

Identifizierung und Charakterisierung von Interaktionen synaptischer Proteine aus Mus musculus.  

E-print Network

??Das postsynaptische Protein Neurobeachin brachte in einer Hefe-2-Hybrid-Suche die Interaktion zwischen der BEACH-Domäne mit dem Transkriptionsfaktor PLZF hervor. Diese Interaktion konnte in weiteren Experimenten aber… (more)

Kasper-Sonnenberg, Monika

2005-01-01

263

Klinisch-psychologische Aspekte der Mensch-Medien Kommunikation.  

E-print Network

??In dieser Diplomarbeit wurden einerseits Online-Dating in Verbindung mit dem klinischen Zustand der sozialen Phobie und andererseits Unterschiede zwischen deutschsprechenden und norwegischen Online-Dater/innen erforscht. Dies… (more)

Aunet, Kirsti Margrethe

2011-01-01

264

Erasmus Semester Lancaster University Linguistics and English Language Department 13.09.2013 -13.12.2013  

E-print Network

auf dem ,War of Roses` zwischen York und Lancaster und wird jedes Jahr zwischen der Lancaster LU bewerben. Wenn man erfolgreich war, folgt eine online Bewerbung an der LU selbst. Dabei geht es war die Anreise auch mit viel Gepäck ein leichtes und erste Kontakte knüpft man auch sehr schnell

Greifswald, Ernst-Moritz-Arndt-Universität

265

Semi-automatic recognition and mapping of event-induced landslides by exploiting multispectral satellite images and DEM in a Bayesian framework  

NASA Astrophysics Data System (ADS)

Landslides occur every year in many areas of the world, causing casualties, economic and environmental losses. Landslide inventory maps are important to document the extent of the landslide phenomena in a region, for risk estimation and management, and to study landscape evolution. We present a method to facilitate the semi-automatic recognition and mapping of event induced shallow landslides. The method is based on the combination in a Bayesian framework of information extracted from High Resolution optical multispectral satellite images and Digital Elevation Models (DEM). The landslide membership probability is estimated from post-event satellite images using a supervised image classification method. The likelihood of landslide occurrence is obtained adopting a "data-driven" approach, intersecting existing landslide inventories with maps of morphometric parameters (slope and curvature) calculated from the DEM. We tested the method in the Huaguoshan basin, Taiwan, where it proved capable of detecting and mapping landslides triggered by Typhoon Morakot in August 2009. Compared to other pixel-based approaches, the method reduces significantly the typical "salt-and-pepper" effect of landslide classifications, and allows the internal classification of landslide areas in landslide source areas and landslide travel and depositional ("run out") areas.

Mondini, Alessandro C.; Chang, Kang-tsung; Rossi, Mauro; Marchesini, Ivan; Guzzetti, Fausto

2012-10-01

266

Application of the inundation area—lake level rating curves constructed from the SRTM DEM to retrieving lake levels from satellite measured inundation areas  

NASA Astrophysics Data System (ADS)

Remote sensing technology has great potential for measuring lake inundation areas and lake levels, and providing important lake water quantity and quality information which can be used for improving our understanding of climate change impacts on the global water cycle, and assessing the influence of the projected future climate change on the global water resources. One remote sensing approach is to estimate lake level from satellite measured inundation area based on the inundation area—lake level rating (IALLR) curves. However, this approach is not easy to implement because of a lack of data for constructing the IALLR curves. In this study, an innovative and robust approach to construct the IALLR curves from the digital elevation model (DEM) data collected during the Shuttle Radar Topography Mission (SRTM) was developed and tested. It was shown that the IALLR curves derived from the SRTM DEM data could be used to retrieve lake level from satellite measured inundation area. Applying the constructed IALLR curve to the estimated inundation areas from 16 Landsat Thematic Mapper (TM) images, 16 lake levels of Lake Champlain in Vermont were obtained. The root mean square error (RMSE) of the estimated lake levels compared to the observed water levels at the U.S. Geological Survey (USGS) gauging station (04294500) at Burlington, Vermont is about 0.12 m.

Pan, Feifei; Liao, Jingjuan; Li, Xinwu; Guo, Huadong

2013-03-01

267

Uplift mechanism for a shallow-buried structure in liquefiable sand subjected to seismic load: centrifuge model test and DEM modeling  

NASA Astrophysics Data System (ADS)

Based on a centrifuge model test and distinct element method (DEM), this study provides new insights into the uplift response of a shallow-buried structure and the liquefaction mechanism for saturated sand around the structure under seismic action. In the centrifuge test, a high-speed microscopic camera was installed in the structure model, by which the movements of particles around the structure were monitored. Then, a two-dimensional digital image processing technology was used to analyze the microstructure of saturated sand during the shaking event. Herein, a numerical simulation of the centrifuge experiment was conducted using a two-phase (solid and fluid) fully coupled distinct element code. This code incorporates a particle-fluid coupling model by means of a "fixed coarse-grid" fluid scheme in PFC3D (Particle Flow Code in Three Dimensions), with the modeling parameters partially calibrated based on earlier studies. The physical and numerical models both indicate the uplifts of the shallow-buried structure and the sharp rise in excess pore pressure. The corresponding micro-scale responses and explanations are provided. Overall, the uplift response of an underground structure and the occurrence of liquefaction in saturated sand are predicted successfully by DEM modeling. However, the dynamic responses during the shaking cannot be modeled accurately due to the restricted computer power.

Zhou, Jian; Wang, Zihan; Chen, Xiaoliang; Zhang, Jiao

2014-06-01

268

An integrated Quality by Design (QbD) approach towards design space definition of a blending unit operation by Discrete Element Method (DEM) simulation.  

PubMed

A combined Quality by Design (QbD) and Discrete Element Model (DEM) simulation-approach is presented to characterize a blending unit operation by evaluating the impact of formulation parameters and process variables on the blending quality and blending end point. Understanding the variability of both the API and the excipients, as well as their impact on the blending process are critical elements for blending QbD. In a first step, the QbD-methodology is systematically used to (1) establish the critical quality attribute content uniformity and to link this CQA to its surrogate blend homogeneity, (2) identify potentially critical input factors that may affect blending operation quality and (3) risk-rank these factors to define activities for process characterization. Subsequently, a DEM-simulation-based characterization of the blending process is performed. A statistical evaluation is finally presented, relating blend homogeneity of systems with low particle number to the regulatory requirements. Data are then used to map out a three-dimensional knowledge space, providing parameters to define a design space and set up an appropriate control strategy. PMID:21056102

Adam, Siegfried; Suzzi, Daniele; Radeke, Charles; Khinast, Johannes G

2011-01-18

269

Application of Positron Emission Particle Tracking (PEPT) to validate a Discrete Element Method (DEM) model of granular flow and mixing in the Turbula mixer.  

PubMed

The laboratory-scale Turbula mixer comprises a simple cylindrical vessel that moves with a complex, yet periodic 3D motion comprising of rotation, translation and inversion. Arising from this complexity, relatively few studies to obtain fundamental understanding of particle motion and mixing mechanisms have been reported. Particle motion within a cylindrical vessel of a Turbula mixer has been measured for 2mm glass spheres using Positron Emission Particle Tracking (PEPT) in a 2l blending mixing vessel at 50% fill level. These data are compared to results from Discrete Element Method (DEM) simulations previously published by the authors. PEPT mixing experiments, using a single particle tracer, gave qualitatively similar trends to the DEM predictions for axial and radial dispersion as well as for the axial displacement statistics at different operational speeds. Both experimental and simulation results indicate a minimum mixing efficiency at ca. 46 rpm. The occupancy plots also show a non-linear relationship with the operating speed. These results add further evidence to a transition between two flow and mixing regimes. Despite the similarity in overall flow and mixing behaviour measured and predicted, including the mixing speed at which the flow behaviour transition occurs, a systematic offset between measured and predicted result is observed. PMID:23376506

Marigo, M; Davies, M; Leadbeater, T; Cairns, D L; Ingram, A; Stitt, E H

2013-03-25

270

GPS radio occultation with TerraSAR-X and TanDEM-X: sensitivity of lower troposphere sounding to the Open-Loop Doppler model  

NASA Astrophysics Data System (ADS)

The Global Positioning System (GPS) radio occultation (RO) technique provides valuable input for numerical weather prediction and is considered as a data source for climate related research. Numerous studies outline the high precision and accuracy of RO atmospheric soundings in the upper troposphere and lower stratosphere. In this altitude region (8-25 km) RO atmospheric soundings are considered to be free of any systematic error. In the tropical (30° S-30° N) Lower (<8 km) Troposphere (LT), this is not the case; systematic differences with respect to independent data sources exist and are still not completely understood. To date only little attention has been paid to the Open Loop (OL) Doppler model. Here we report on a RO experiment carried out on-board of the twin satellite configuration TerraSAR-X and TanDEM-X which possibly explains to some extent biases in the tropical LT. In two sessions we altered the OL Doppler model aboard TanDEM-X by not more than ±5 Hz with respect to TerraSAR-X and compare collocated atmospheric refractivity profiles. We find a systematic difference in the retrieved refractivity. The bias mainly stems from the tropical LT; there the bias reaches up to ±1%. Hence, we conclude that the negative bias (several Hz) of the OL Doppler model aboard TerraSAR-X introduces a negative bias (in addition to the negative bias which is primarily caused by critical refraction) in our retrieved refractivity in the tropical LT.

Zus, F.; Beyerle, G.; Heise, S.; Schmidt, T.; Wickert, J.

2014-12-01

271

Delineation of subglacial bedrock structure in glaciated regions using DEMs derived from stereoscopic satellite imagery: An example of the Land Glacier catchment, West Antarctica  

NASA Astrophysics Data System (ADS)

The Land Glacier of coastal Marie Byrd Land is proximal to the inferred tectonic boundary between the Ross and Amundsen provinces of the Marie Byrd Land terrane in West Antarctica. Its asymmetrical upper catchment draws ice from the volcanic peaks of the western Flood Range, a linear mountain change that is thought to be fault-controlled. A north-flowing ice stream with velocities >1200m/yr, Land Glacier occupies a narrow outlet flanked by sparse rock exposures along the remote Hobbs Coast. The narrow configuration and high flow velocity of the ice stream, together with the contrast in rock types on either side, suggest that the locus of Land Glacier is controlled by bedrock structures, however no faults have been mapped in this remote region on the basis of traditional ground-based methods nor airborne geophysics. We employ a new approach to mapping of subglacial bedrock faults and geological contacts in this region that entails quantitative analysis of high resolution DEMs computed from high resolution WorldView stereographic imagery. DEMs are computed using ERDAS Imagine's LPS eATE algorithm, followed by MATLAB-based routines to interpolate and remove artifacts in the terrain model. The resolution of the ice sheet DEM is 3 to 5 m, providing sufficient resolution for identification of geometrically regular features in the ice surface topography that may be attributable to bedrock faults and lithological contacts. The first phase of our ongoing work focuses upon lineaments that form a systematic array with regular geometry and spacing, that may be fault-controlled. A procedure involving use of hillshade applied from multiple sun angles, slope aspect, and slope gradient analysis of the high resolution DEMs was carried out in ArcGIS for characterization of the surface lineaments. We used the following criteria to distinguish bedrock-controlled lineaments from ice flow lineations: 1) laterally continuous for a minimum distance of 3 km, 2) vertical relief of ? 50m across a lineament, and 3) a minimum gradient of 5°. Raster layers of computed slope and aspect were cross-referenced to DEMs to confirm the location and geometry of lineaments that were identified. For the Land Glacier region, we discern two dominant sets of km-scale lineaments oriented ~E-W (~270-285°) and NW-SE (315-330°). The E-W trending lineaments are the most abundant and laterally continuous, with lengths up to 20 km and relief as high as 150 m. This trend is parallel to that of the Flood Range volcanoes that are ? 6 Ma in age. The NW-SE trending lineations range up to 14 km in length and attain 180 m of relief; they are coparallel to the alignment in the Ames Range (volcano ages 6 to 15 Ma). Potentially the regionally extensive Land Glacier lineament array is controlled by bedrock structures formed or reactivated during two Neogene stress states (e.g. Paulson & Wilson (2010, JGSL v167). Structural inheritance is a likelihood due to protracted tectonism and lithospheric thinning in West Antarctica since Cretaceous time.

Robertson, A. M.; Contreras, A.; Siddoway, C. S.; Gottfried, M.; Porter, C.

2012-12-01

272

Tibiale Torsionsfehler  

Microsoft Academic Search

Zusammenfassung  \\u000a Tibiale Torsionsfehler sind meistens klinisch nicht sehr evident und werden deshalb häufig übersehen. Zur Messung der statischen\\u000a Tibiatorsion hat sich am besten die klinische Untersuchung und das CT bewährt, während für die dynamische Messung die Klinik\\u000a und das Ganglabor zum Einsatz kommen. Es gibt nur wenige Studien, die einen Zusammenhang zwischen einem Torsionsfehler des\\u000a Unterschenkels (US) und zu erwartenden

C. Lampert; B. Thomann; R. Brunner

2000-01-01

273

Development of Flood Inundation Libraries using Historical Satellite Data and DEM for Part of Godavari Basin: An Approach Towards Better Flood Management  

NASA Astrophysics Data System (ADS)

Conventional method of identifying areas to be inundated for issuing flood alert require inputs like discharge data, fine resolution digital elevation model (DEM), software for modelling and technically trained manpower to interpret the results meaningfully. Due to poor availability of these inputs, including good network of historical hydrological observations and limitation of time, quick flood early warning becomes a difficult task. Presently, based on the daily river water level and forecasted water level for major river systems in India, flood alerts are provided which are non-spatial in nature and does not help in understanding the inundation (spatial dimension) which may be caused at various water levels. In the present paper a concept for developing a series of flood-inundation map libraries two approaches are adopted one by correlating inundation extent derived from historical satellite data analysis with the corresponding water level recorded by the gauge station and the other simulation of inundation using digital elevation model (DEM's) is demonstrated for a part of Godavari Basin. The approach explained can be one of quick and cost-effective method for building a library of flood inundation extents, which can be utilized during flood disaster for alerting population and taking the relief and rescue operations. This layer can be visualized from a spatial dimension together with other spatial information like administrative boundaries, transport network, land use and land cover, digital elevation data and satellite images for better understanding and visualization of areas to be inundated spatially on free web based earth visualization portals like ISRO's Bhuvan portal (http://bhuvan.nrsc.gov.in). This can help decision makers in taking quick appropriate measures for warning, planning relief and rescue operations for the population to get affected under that river stage.

Bhatt, C. M.; Rao, G. S.; Patro, B.

2014-12-01

274

Topographic precursors and geological structures of deep-seated catastrophic landslides caused by typhoon Talas, determined from the analysis of high-resolution DEMs  

NASA Astrophysics Data System (ADS)

Typhoon Talas crossed the Japanese Islands between 2 and 5 September 2011, causing more than 70 deep-seated catastrophic landslides in a Jurassic to Paleogene-Early Miocene accretion complex. Detailed examination of the topographic features of 10 large landslides before the event, recorded on DEMs with a resolution of 1 m (based on airborne laser scanner surveys), showed that all of the landslides had small scarplets near their future crowns prior to the slide, and one landslide had linear depressions along its future crown as precursor topographic features. These scarplets and linear depressions were caused by gravitational slope deformation that preceded the catastrophic failure. Strains, defined by the ratio of the length of a scarplet to the length of the whole slope (as measured along the slope line), ranged from 5% to 21%, and are the first reliable numerical data relating to the topographic precursor features of large and catastrophic landslides. Careful examination of aerial photographs from another four large landslides, for which no high-resolution DEMs were available, suggested that they also developed scarplets at their heads beforehand, which are not precisely quantified. Twelve of the 14 landslides we surveyed in the field had sliding surfaces with wedge-shaped discontinuities that consisted of faults, shear surfaces that formed during accretion, and bedding, suggesting that the buildup of pore pressure occurs readily in a gravitationally deformed rock body containing wedge-shaped discontinuities. Other types of gravitational deformation were also active; e.g., flexural toppling and buckling were each observed to have preceded one landslide.

Chigira, Masahiro; Tsou, Ching-Ying; Matsushi, Yuki

2013-04-01

275

Time-averaged discharge rate of subaerial lava at K?lauea Volcano, Hawai`i, measured from TanDEM-X interferometry: Implications for magma supply and storage during 2011-2013  

NASA Astrophysics Data System (ADS)

digital elevation models (DEMs) derived from TerraSAR add-on for Digital Elevation Measurements (TanDEM-X) synthetic aperture radar imagery provides a measurement of elevation change over time. On the East Rift Zone (EZR) of K?lauea Volcano, Hawai`i, the effusion of lava causes changes in topography. When these elevation changes are summed over the area of an active lava flow, it is possible to quantify the volume of lava emplaced at the surface during the time spanned by the TanDEM-X data—a parameter that can be difficult to measure across the entirety of an ~100 km2 lava flow field using ground-based techniques or optical remote sensing data. Based on the differences between multiple TanDEM-X-derived DEMs collected days to weeks apart, the mean dense-rock equivalent time-averaged discharge rate of lava at K?lauea between mid-2011 and mid-2013 was approximately 2 m3/s, which is about half the long-term average rate over the course of K?lauea's 1983-present ERZ eruption. This result implies that there was an increase in the proportion of lava stored versus erupted, a decrease in the rate of magma supply to the volcano, or some combination of both during this time period. In addition to constraining the time-averaged discharge rate of lava and the rates of magma supply and storage, topographic change maps derived from space-based TanDEM-X data provide insights into the four-dimensional evolution of K?lauea's ERZ lava flow field. TanDEM-X data are a valuable complement to other space-, air-, and ground-based observations of eruptive activity at K?lauea and offer great promise at locations around the world for aiding with monitoring not just volcanic eruptions but any hazardous activity that results in surface change, including landslides, floods, earthquakes, and other natural and anthropogenic processes.

Poland, Michael P.

2014-07-01

276

Informationstechnologie, Governance und Compliance  

Microsoft Academic Search

Zusammenfassung  In dem Beitrag werden die Ergebnisse einer Web-Recherche zu den Themen Governance und Compliance in Zusammenhang mit dem Einsatz\\u000a von Informationstechnologie vorgestellt. Hierbei zeigt sich, dass die Informationstechnologie eine doppelte Rolle einnimmt.\\u000a Sie tritt zum einen als Instrument zur Realisierung der betrieblichen Governance und Compliance in Erscheinung. Zum anderen\\u000a ist die IT auch ein wesentlicher Gegenstand von Governance und Compliance,

Alexander Teubner; Tom Feller

2008-01-01

277

Die Typenbestimmung von Brucellen und ihre Bedeutung fÜr die Systematik des Genus Brucella  

Microsoft Academic Search

Zusammenfassung Durch die Untersuchung der Farbstoffresistenz, der Schwefelwasserstoffbildung, der Ureaseaktivität, des Verhaltens gegenÜber DEDTC und der Agglutinabilität in monospezifischen Seren wurde die Typenzugehörigkeit von 164 Brucellastämmen untersucht. Neben den Typen abortus, melitensis und suis kommen Stämme vor, die weder dem einen noch dem anderen Typ eindeutig zugeordnet werden können und als Übergangsformen zwischen den klassischen Brucellatypen stehen. In Anbetracht der

Wilhelm Wundt

1958-01-01

278

Die gelben Engel von Noehtam  

NASA Astrophysics Data System (ADS)

Pech gehabt: Eine Panne auf der Autobahn! Zum Glück gibt es den ADAC. Etwa 30 Minuten nach dem Anruf aus der Notrufsäule steht ein Hilfefahrzeug beim Autofahrer mit der Panne - wir nennen ihn hier Havaristen. Damit das funktioniert, muss zwischen dem Anruf in einer ADAC-Hilfezentrale und der Ankunft eines gelben Engels eine Menge organisiert werden.

Rambau, Jörg

279

On the investigation of the performances of a DEM-based hydrogeomorphic floodplain identification method in a large urbanized river basin: the Tiber river case study in Italy  

NASA Astrophysics Data System (ADS)

Floodplains are critical landscape features for their importance in both ecohydrological and socio-economic terms. River valleys are, in fact, the domain where the interdependence of the complex human-environmental interface is more significant. Riparian zones, along perennial channels, where the frequency of saturation is high and most flooding occurs, are also the areas where urban areas and infrastructures (e.g. highways, bridges, railways, etc) are more present. This is mainly due to geomorphologic conditions since those areas are predominantly flat and easier to develop. One of the more challenging issues under changing climatic, environmental and human drivers for implementing efficient current and future urban plans is to accurately and timely identify, map and characterize the potential flooding scenarios of floodplains. This is currently achieved by implementing detailed topographic, hydrologic and hydraulic studies for flood modeling and mapping for different frequencies (i.e. return time), but those activities are rarely implemented at the large (river basin) scale for their economic cost and time of implementation. In addition to that, flood map updating is not as frequent as needed for following the rapid changing land use conditions. As a result, it is very often the case that urban plans are based on heterogeneous and discontinuous flood map information. Nevertheless, several recent researches demonstrated the potential for the use of high resolution digital elevation models (DEMs) to define the floodplain feature by means of automated hydrogeomorphic methods. This means identifying the flood prone area by filtering potentially inundated cells by implementing proper morphological and hydrological analyses. In this work we implemented the flooplain identification model proposed by Nardi et al. (WRR, 2006) which automatically extract the river network and estimate flood water levels according to a predefined scaling Leopold law. Inundated areas are consequently identified as those river buffers, draining towards the channel, with an elevation that is less than the maximum flow depth of the corresponding outlet. Keeping in mind that this hydrogeomorhic model performances are strictly related to the quality and properties of the input DEM and that the intent of this kind of methodology is not to substitute standard flood modeling and mapping methods, in this work the performances of this approach are qualitatively evaluated by comparing results with standard flood maps. The Tiber river basin was selected as case study, one of the main river basins in Italy covering a drainage area of approximately 17.000 km2. This comparison is interesting for understanding the performance of the model in a large and complex domain where the impact of the urbanization matrix is significant. Results of this investigation confirm the potential of such DEM-based floodplain mapping models for providing a fast timely homogeneous and continuous inundation scenario to urban planners and decision makers, but also the drawbacks of using such methodology where the humans are significantly and rapidly modifying the surface properties.

Nardi, Fernando; Biscarini, Chiara; Di Francesco, Silvia; Manciola, Piergiorgio

2013-04-01

280

Evaluation of the influence of metabolic processes and body composition on cognitive functions: Nutrition and Dementia Project (NutrDem Project).  

PubMed

The global increase in the prevalence of dementia and its associated comorbidities and consequences has stimulated intensive research focused on better understanding of the basic mechanisms and the possibilities to prevent and/or treat cognitive decline or dementia. The etiology of cognitive decline and dementia is very complex and is based upon the interplay of genetic and environmental factors. A growing body of epidemiological evidence has suggested that metabolic syndrome and its components may be important in the development of cognitive decline. Furthermore, an abnormal body mass index in middle age has been considered as a predictor for the development of dementia. The Nutrition and Dementia Project (NutrDem Project) was started at the Department of Old Age Psychiatry and Psychotic Disorders with close cooperation with Department of Medical Psychology. The aim of this study is to determine the effect of dietary patterns, nutritional status, body composition (with evaluation of visceral fat) and basic regulatory mechanisms of metabolism in elderly patients on cognitive functions and the risk of cognitive impairment (mild cognitive impairment and/or dementia). PMID:25139556

Magierski, R; K?oszewska, I; Sobow, T

2014-11-01

281

Modeling the evolution of loess-covered landforms in the Loess Plateau of China using a DEM of underground bedrock surface  

NASA Astrophysics Data System (ADS)

The evolution of loess-covered landforms is largely controlled by the pre-Quaternary underlying bedrock terrain, which is one of the most important factors in understanding the formation mechanism of the landforms. This study used multiple data sources to detect 1729 outcropping points of underlying terrain, in order to construct a digital elevation model (DEM) of the paleotopography of an area of the Loess Plateau subject to severe soil erosion. Four terrain characteristics, including terrain texture, slope gradient, the hypsometric curve, and slope aspect, were used to quantify topographic differences and reveal the loess-deposition process during the Quaternary. A loess thickness map was then created to show the spatial distribution of loess deposits in the test area. Finally, the geomorphological inheritance characteristics of the loess-covered landforms were evaluated in different landform divisions. The results showed the significant inheritance of modern topography from the underlying topography with a similar general relief trends. The average thickness of loess deposits was computed to be 104.6 m, with the thickest part located in the Xifeng loess tableland area. In addition, the slope aspects of the North and Northwest seem to have favored Quaternary loess deposition, which supported the hypothesis of an eolian origin for loess in China. The modern surface has lower topographic relief compared to the underlying terrain due to loess deposition.

Xiong, Li-Yang; Tang, Guo-An; Li, Fa-Yuan; Yuan, Bao-Yin; Lu, Zhong-Chen

2014-03-01

282

DemTect, PANDA, EASY, and MUSIC: cognitive screening tools with age correction and weighting of subtests according to their sensitivity and specificity.  

PubMed

Many cognitive screening instruments have been developed during the last decades to detect mild cognitive dysfunction and dementia, and there is an ongoing discussion as to which tool should be used in which setting and which challenges have to be considered. Among other aspects, dependence on age is a recognized problem in screening tools which still has not found its way into common scoring procedures. Another aspect which has been handled very heterogeneously is which domain is represented in which proportion in the total score. Furthermore, screening ethnic minority patients has been identified as an important but so far widely unresolved matter. In this review, four cognitive screening tools that all follow a common, stringent concept and pay regard to some critical aspects are described: the DemTect, a "generic" tool; the PANDA for Parkinson's disease patients; the EASY, a non-verbal, culture-fair screening test for patients with migration background; and the MUSIC for patients with multiple sclerosis. All of these screening instruments have an age-correction, provide a total score in which the different subtests are weighted according to their individual sensitivity and specificity, and include tasks that are specifically aligned to the cognitive profile of the target group, including the EASY with non-verbal, culture-fair tasks to overcome language and cultural barriers. The development, main characteristics, data, and limitations of these tools are presented and discussed against the background of the current landscape of cognitive screening tools. PMID:23313929

Kalbe, Elke; Calabrese, Pasquale; Fengler, Sophie; Kessler, Josef

2013-01-01

283

Kanban - der Weg ist das Ziel  

NASA Astrophysics Data System (ADS)

Wenn man aktuell Produktionsbereiche in Deutschland und Europa besucht, fallen im Zusammenhang mit modernen Produktionsmethoden immer öfter die Begriffe Kanban (jap. Karte, Signal) und Pull-Produktion, und dies nicht ohne Stolz, da diese mit dem schillernden Vorbild des Toyota Produktionssystems in Zusammenhang stehen. Tatsächlich ist Kanban ein integraler Bestandteil moderner Produktionssysteme. Blickt man aber im Rahmen von Prozessanalysen hinter die Fassaden", d. h. in die tägliche Praxis der Arbeitsprozesse, wird man schnell desillusioniert - die viel gepriesenen klassischen Kanban-Regeln werden im Tagesgeschäft nicht eingehalten.

Aull, Florian; Berlak, Joachim; Dickmann, Eva; Dickmann, Philipp; Fischäder, Holm; Gerlach, Joachim; Henneberg, Jens; Kapalla, Klaus; Kress, Oliver; Kuttler, Robert; Schneider, Herfried M.; Schürle, Philipp; Stellpflug, Franz-Josef; Wannenwetsch, Ralph; Wulz, Johannes; Zäh, Michael F.

284

Konsiliarisch-psychiatrische versorgung eines Allgemeinkrankenhauses im zusammenhang mit stationärer kriseninterventio  

Microsoft Academic Search

Summary This study examined the psychiatric care given at a general hospital associated with a clinical crisis-intervention ward in Munich. The correlations between frequency of suicide attempts, psychiatric crisis and the transfer of patients (treated by attending physicians) to a crisis-intervention ward of particular interest. Of the total 6,004 patients in the general hospital, 227 (130 female, 97 male) were

Christian Vogel; Cord-Michael Haf

1986-01-01

285

Beiträge zur ernährungsbiologie einheimischer süsswasserprosobranchier  

Microsoft Academic Search

1.Untersucht wurden 4 Süßwasserprosobranchier: Bithynia tentaculata L., Theodoxus fluviatilis L., Lithoglyphus naticoides C.Pfr. und Valvata piscinalisMüll.2.Bithynia ist in der Lage, die mit dem Atemwasser eingestrudelten Partikel durch die Ausbildung eines Kiemenschleimfilters abzufiltrieren, sie zur Nahrungswurst zu formen und auf einem besonderen Wege dem Munde zuzuführen. Das Tier vermittelt erndhrungsphysiologisch zwischen Strudlern und Schlammfressern.3.Theodoxus befördert die mit dem Atemstrom eingestrudelten Detrituspartikelchen

Heinrich Schäfer

1953-01-01

286

SPIRIT DEM applications over Svalbard  

E-print Network

output · Only 3D-shifts 13 Geolocation accuracy / co-registration (C. Nuth) Nuth and Kääb, in prep. #12;A) · Topographic phase for 2-pass InSAR · Orthoprojection of automatic camera data · Glacier outline mapping. Kääb GUIO NO-Oslo Uni 3 topography A. Shepherd SGUE UK-Edinburgh Uni 4 elevation change T. Strozzi

Berthier, Etienne

287

Nach dem TGN1412-Zwischenfall  

Microsoft Academic Search

\\u000a Zusammenfassung\\u000a   Der Einsatz monoklonaler Antikörper hat auf vielen klinischen Gebieten zu neuen therapeutischen Möglichkeiten geführt. Er\\u000a birgt aber auch Risiken, wie das akute Auftreten eines Zytokinsturms bei der Erstanwendung von TGN1412, einem Superagonisten\\u000a gegen CD28, im März 2006 gezeigt hat. Dieser Artikel beschreibt die Prinzipien, die das Paul-Ehrlich-Institut (PEI) bei der\\u000a wissenschaftlichen Bewertung von Anträgen auf klinische Prüfung zur Erstanwendung

C. K. Schneider; U. Kalinke

2007-01-01

288

Remote-sensing of Riverine Environments Utilized by Spawning Pallid Sturgeon Using a Suite of Hydroacoustic Tools and High-resolution DEMs  

NASA Astrophysics Data System (ADS)

The pallid sturgeon (Scaphirynchus albus) inhabits sandy-bedded rivers in the Mississippi River basin including the Missouri and Lower Yellowstone Rivers and has experienced decline generally associated with the fragmentation and alteration of these river systems. Knowledge gaps in the life history of the pallid sturgeon include lack of an understanding of conditions needed for successful reproduction and recruitment. We employed hydroacoustic tools to investigate habitats utilized by spawning pallid sturgeon in the Missouri River in Missouri, Kansas, Iowa, and Nebraska, and the Yellowstone River in Montana and North Dakota USA from 2008-2013. Reproductive pallid sturgeon were tracked to suspected spawning locations by field crews using either acoustic or radio telemetry, a custom mobile mapping application, and differential global positioning systems (DGPS). Female pallid sturgeon were recaptured soon after spawning events to validate that eggs had been released. Habitats were mapped at presumed spawning and embryo incubation sites using a multibeam echosounder system (MBES), sidescan sonar, acoustic Doppler current profiler, an acoustic camera and either a real-time kinematic global positioning system (RTK GPS) or DGPS. High-resolution DEM's and velocimetric maps were gridded from at a variety of scales from 0.10 to 5 meters for characterization and visualization at spawning and presumed embryo incubation sites. Pallid sturgeon spawning sites on the Missouri River are deep (6-8 meters) and have high current velocities (>1.5 meters per second). These sites are also characterized by high turbidity and high rates of bedload sediment transport in the form of migrating sand dunes. Spawning on the channelized Lower Missouri River occurs on or adjacent to coarse angular bank revetment or bedrock. Collecting biophysical information in these environmental conditions is challenging, and there is a need to characterize the substrate and substrate condition at a scale relevant to spawning fish and developing embryos (< 1 meter). The Yellowstone River in Montana and North Dakota provides the closest analog to a reference condition for pallid sturgeon spawning habitat with a natural flow regime and relatively natural channel geomorphology. Recent documented suspected spawning on the Yellowstone River occurs in a a sand-bedded reach with patches of gravel deposits, in zones of higher velocity (1.0-1.5 meters per second) compared to the ranges of velocities available in an adjacent reach and over a range of depths (2-5 meters). Results from substrate assessments at pallid sturgeon spawning sites on the Missouri and Yellowstone Rivers may have implications for sediment and flow management as well as provide guidance for potential habitat manipulation in support of the recovery of the pallid sturgeon.

Elliott, C. M.; Jacobson, R. B.; DeLonay, A. J.; Braaten, P. J.

2013-12-01

289

Tightening the River Meander-Belt: Application of a Topographic Erodible Corridor Concept Using DEM Raster Analysis. A Case Study of Highland Creek, Ontario.  

NASA Astrophysics Data System (ADS)

Planimetric river hazard assessments, typically delineated as meander-belts, are complicated in southern Ontario by rivers which are incised into thick glacial sediments. Active and relic floodplain surfaces are topographically diverse, with river terraces commonly observed in the valleys due to deglacial and Holocene incision. Consequently, channels are often in contact with a mixed boundary of alluvial and glaciogenic sediments. Accepted meander-belt delineation procedures and protocols vary between intra-national and international jurisdictions; however, a focus on planimetric mapping and historical techniques is common place. In the southern Ontario context, this type of reach-scale river hazard assessment is important for protection of upland property, erosion risks to valley bottom infrastructure, and delineation of new development limits. Given the ecological and public safety benefits, there is growing acceptance and expectation that river bank erosion processes should be preserved within an erodible corridor, with a decreased emphasis on channel intervention and engineering approaches where possible. However, the use of planimetric meander- belt delineation techniques for incised valley settings frequently meets both practical and conceptual challenges. This study explores the potential for a Topographic Erodible Corridor Concept (TECC) as an improved representation of river evolution compared to the traditional planimetric techniques, particularly in previously glaciated regions. Such a concept would account for differences in erodible volumes of sediment associated with topographic variations within incised river valleys. Application of this concept is investigated using raster analysis of a high resolution digital elevation model (DEM), within widely available GIS software. Initial results from a case study on Highland Creek (Ontario) confirm that the corridor alignment and diverse topography of the incised valley morphology are well represented by a TECC model, which can be translated into a detailed assessment of erosion risks. Erosion rate estimates may still require historical overlay techniques to characterize channel migration rates. However, it is proposed that development of a regional-scale probability distribution of erosion rates may later be integrated into the TECC model to constrain the erodible corridor envelope within typical planning horizons. Such probability distributions may be indexed to reach-scale characteristics such as stream power, boundary material, or basin landuse, for example. Sensitivity of local bank erosion rates to particular channel alignments, processes, and boundary materials may be considered in future TECC models to improve representation of lateral migration processes and avulsion potential. The TECC model also provides a solid framework to integrate geotechnical stable-slope analyses to erodible valley walls for confined valley settings.

Phillips, R. T.

2009-05-01

290

Unterschiede zwischen Evidence-Based Medicine und konventionell bester Medizin  

Microsoft Academic Search

Zusammenfassung  ? Die Umsetzung rationaler Konzepte im Gesundheitssystem wird möglich sein, wenn zwei Bedingungen erfüllt sind: Die gesetzlichen\\u000a Rahmenbedingungen müssen auf dieses Ziel abgestimmt sein, und neue Strategien sind zu etablieren. Die neuen Strategien werden\\u000a benötigt, um aus der Informationsflut die Daten zu finden, welche tatsächlich «Evidenz» zur Begründung des medizinischen Fortschritts\\u000a enthalten.\\u000a \\u000a Evidence-Based Medicine (EBM) bietet diese Strategien an. Um

Franz Porzsolt; Regina Kunz

1997-01-01

291

Politische Strategien der MILF zwischen Djihadismus und Verhandlungstisch  

Microsoft Academic Search

Nach Jahrzehnten sozialer und politischer Repression erwachte im Jahr 1968 das politische Bewusstsein der muslimischen Bevölkerung Mindanaos. Im Jahr 1969 gründete der säkulare Moslem Nurullaji Misuari die Moro National Liberation Front (MNLF), die bald die Führung im Widerstand gegen die philippinische Zentralregierung übernahm. Ideologische Spannungen innerhalb der MNLF führten seit 1976 zum Ende ihrer organisatorischen Einheit: Eine Fraktion hatte sich

Nicole Klitzsch

2006-01-01

292

Zum Briefwechsel zwischen Gottfried Kirch und Gottfried Wilhelm von Leibniz  

Microsoft Academic Search

\\u000a Summary  Between June 1702 and December 1708 the astronomer, Kirch in Berlin and the philosopher, Leibniz in Hannover exchanged eleven\\u000a letters. The letters from Leibniz to Kirch were published in 1900. The author will prove in this article, that the letters,\\u000a which are kept in the Leibniz-Archives in Hannover, are Kirch's original answers to Leibniz. For first time, these letters\\u000a will

Klaus-Dieter Herbst

1994-01-01

293

New insights into palaeoglaciological processes in northeastern Germany by analysis of a LiDAR DEM: using high-resolution elevation data to reassess the geomorphology of the Barnim till plain  

NASA Astrophysics Data System (ADS)

We used airborne LiDAR DEM data to reassess the current state of research of an intensively studied "classical" glacial landscape, the Barnim till plain northeast of Berlin. To gain new insights into palaeoglaciological dynamics, we examined a high-resolution DEM for geomorphic features that either prove or negate previous research. The study area was last glaciated in the Weichselian, and its landforms are associated with the W1B- (Brandenburg phase) and W1F-advances (Frankfurt phase), except for the eastern Barnim where a push moraine complex was compressed during the Saalian. The course and the timing of the W1F ice marginal position, which is assigned to the Barnim area, are contradictorily discussed in literature. Hence, landscape analysis with a high resolution DEM appears to be a promising tool. The LiDAR data used here has a ground resolution of 1 m and a height accuracy of 30 - 50 cm. In an ArcGIS 10 environment a database was created that contains spatial information about the study area collected from different sources. These include digitized geological and geomorphological maps as well as geochronological data from different authors. Owing to the size of the Barnim (~1900 km²), three subsets with a size of 10 x 15 km were selected for advanced analysis (western, middle and eastern Barnim). Each subset represents one of the most characteristic landscapes of the study area. For each subset we performed a qualitative analysis of landscape features. The results were compared with each other and connected to the whole Barnim area as well as the current state of research. The most remarkable discovery was made in the middle Barnim. Here we identified a set of consecutive arcuate ridges. Their widths (NE-SW) are around 1000 - 1500 m, and their lengths are around 10 - 15 km; they rise some 10 m above their surroundings. According to geological maps and our own fieldwork, they are covered by till. A sandy or peaty substrate lies between the ridges. The inner sides of the ridges are northeast-oriented and rather steep, and the outer sides face southwest with a dip at a flatter angle. The ridges are incised radially. Their lobe-like form and the distribution of the substrates suggest a glacial origin. We propose a genetic model of recessional moraines that were deposited in front of an oscillating glacier lobe; however, other possibilities are also discussed. Similar forms were recently found around the ice margin of piedmont glaciers, e.g. the Malaspina glacier in southwest Alaska. The timing of their formation still has to be investigated. Fine gravel analyses from other studies imply that they consist of a till that can probably be associated with a Weichselian ice advance. Understanding the genesis of the newly described ridges may be a key to solve the contradictory "Frankfurt phase problem" in terms of glaciodynamics and stratigraphy Our study shows that even in intensively researched areas high-resolution DEM data can reveal landscape features that shed a new light on landscape genesis. Nevertheless, further fieldwork and geochronological data are necessary to obtain a complete picture of palaeoglaciological processes in the northeastern German lowland.

Hardt, Jacob; Böse, Margot; Hebenstreit, Robert; Lüthgens, Christopher

2014-05-01

294

VERORDNUNG (EG) Nr. 742\\/2003 DER KOMMISSION vom 28. April 2003 zur siebzehnten Änderung der Verordnung (EG) Nr. 881\\/2002 des Rates über die Anwendung bestimmter spezifischer restriktiver Maßnahmen gegen bestimmte Personen und Organisationen, die mit Osama bin Laden, dem Al-Qaida-Netzwerk und den Taliban in Verbindung stehen, und zur Aufhebung der Verordnung (EG) Nr. 467\\/2001 des Rates  

Microsoft Academic Search

DIE KOMMISSION DER EUROPÄISCHEN GEMEINSCHAFTEN — gestützt auf den Vertrag zur Gründung der Europäischen Gemeinschaft, gestützt auf die Verordnung (EG) Nr. 881\\/2002 des Rates vom 27. Mai 2002 über die Anwendung bestimmter spezifischer restriktiver Maßnahmen gegen bestimmte Personen und Orga- nisationen, die mit Osama bin Laden, dem Al-Qaida-Netzwerk und den Taliban in Verbindung stehen, und zur Aufhebung der Verordnung (EG)

Christopher PATTEN

2003-01-01

295

Über das erkenntnistheoretische Raumproblem bei Moritz Schlick, Wilhelm Wundt und Albert Einstein  

Microsoft Academic Search

Dieser Aufsatz beleuchtet das Verhältnis zwischen Moritz Schlick und dem Begründer der experimentellen Psychologie Wilhelm\\u000a Wundt im Hinblick auf ihre Ansichten zum erkenntnistheoretischen Problem des Raumes.1 Es sollen zwei frühe nachgelassene Stücke Schlicks aus seinen durch die Beschäftigung mit der empirischen Psychologie geprägten\\u000a Züricher Jahren (1907–1909) diskutiert werden. Darin setzt er sich mit dem erkenntnistheoretischen Raumproblem in Verbindung\\u000a mit den

Fynn Ole Engler

296

Entwicklung und Aufbau einer Population der Silbermöwe, Larus argentatus argentatus  

Microsoft Academic Search

X. Zusammenfassung Die neben dem Institutsgebäude der Vogelwarte Helgoland in Wilhelmshaven gelegene Silbermöwenpopulation nahm ihren Anfang mit 2 Paaren im Jahre 1948, wuchs bis 1955 auf 51, 1956 auf über 100 Paare an und schwankte 1957–1959 zwischen 127 und 139 Paaren. 1960 waren es mindestens 150 Paare.

R. Drost; E. Focke; G. Freytag

1961-01-01

297

On the nature of scientific laws and theories  

Microsoft Academic Search

Zusammenfassung Ist der Unterschied zwischen wissenschaftlichen Gesetzen und Theorien ein qualitativer oder lediglich von quantitativer Art? Der Autor versucht zu zeigen, daß Gesetze und Theorien fundamental verschieden sind und daß die Kenntnis ihrer verschiedenen Natur notwendig für ein richtiges Wissenschaftsverständnis ist. Aus seiner Sicht sind Theorien geistigeKonstruktionen mit dem Ziel,kausale Erklärungen von empirischen Gesetzen zu geben, während diese Gesetze auf

Craig Dilworth

1989-01-01

298

Abstracts / Association of Institutes for Bee Research Seminar 613 et un arbre pour chacune des varits de Prunus.  

E-print Network

Abstracts / Association of Institutes for Bee Research Seminar 613 et un arbre pour chacune des Stachellose Biene, die im Südosten von Brasilien vorkommt. Bisherige Studien zeigten, dass sich die Popula Microsatelliten dar- auf hin, dass es zwischen Völkern, die über meh- rere Jahre auf dem gleichen Bienenstand

São Paulo, Universidade de

299

Unkrautflora in Mais  

Microsoft Academic Search

In den Jahren 2000 bis 2004 wurde von der Syngenta Agro GmbH in Zusammenarbeit mit der Universität Hohenheim ein Unkrautmonitoring in Mais durchgeführt. Ziel des Monitorings war, das Artenspektrum, die Stärke der Verunkrautung und das Verbreitungsgebiet von Unkrautarten im Maisanbau in Deutschland zu erfassen. Die Unkrauterhebungen wurden jedes Jahr einmal vor der chemischen Unkrautbekämpfung zwischen dem 2. und 6. Blattstadium

J. Mehrtens; M. Schulte; K. Hurle

2005-01-01

300

HEIDELBERGER VORTRGE ZUR KULTURTHEORIE  

E-print Network

-WALLBRECHT (HEIDELBERG) Hörsaal 14 der Neuen Universität Mittwoch, 23. Oktober 2013, 19 Uhr s.t. JOHANN WOLFGANG VON GOETHE: WEST-�STLICHER DIVAN EIN LIEBESGESPR�CH ZWISCHEN HATEM UND SULEIKA MIT KLAVIERST�CKEN VON CLAUDE VON DR. TAREK TAWFIK (KAIRO) GESPR�CH MIT DEM REFERENTEN UND DR. GABRIELE BERRER

Heermann, Dieter W.

301

Shape-selected nanocrystals for in situ spectro-electrochemistry studies on structurally well defined surfaces under controlled electrolyte transport: A combined in situ ATR-FTIR/online DEMS investigation of CO electrooxidation on Pt  

PubMed Central

Summary The suitability and potential of shape selected nanocrystals for in situ spectro-electrochemical and in particular spectro-electrocatalytic studies on structurally well defined electrodes under enforced and controlled electrolyte mass transport will be demonstrated, using Pt nanocrystals prepared by colloidal synthesis procedures and a flow cell set-up allowing simultaneous measurements of the Faradaic current, FTIR spectroscopy of adsorbed reaction intermediates and side products in an attenuated total reflection configuration (ATR-FTIRS) and differential electrochemical mass spectrometry (DEMS) measurements of volatile reaction products. Batches of shape-selected Pt nanocrystals with different shapes and hence different surface structures were prepared and structurally characterized by transmission electron microscopy (TEM) and electrochemical methods. The potential for in situ spectro-electrocatalytic studies is illustrated for COad oxidation on Pt nanocrystal surfaces, where we could separate contributions from two processes occurring simultaneously, oxidative COad removal and re-adsorption of (bi)sulfate anions, and reveal a distinct structure sensitivity in these processes and also in the structural implications of (bi)sulfate re-adsorption on the CO adlayer. PMID:24991511

Jusys, Zenonas; Behm, R Jürgen

2014-01-01

302

Shape-selected nanocrystals for in situ spectro-electrochemistry studies on structurally well defined surfaces under controlled electrolyte transport: A combined in situ ATR-FTIR/online DEMS investigation of CO electrooxidation on Pt.  

PubMed

The suitability and potential of shape selected nanocrystals for in situ spectro-electrochemical and in particular spectro-electrocatalytic studies on structurally well defined electrodes under enforced and controlled electrolyte mass transport will be demonstrated, using Pt nanocrystals prepared by colloidal synthesis procedures and a flow cell set-up allowing simultaneous measurements of the Faradaic current, FTIR spectroscopy of adsorbed reaction intermediates and side products in an attenuated total reflection configuration (ATR-FTIRS) and differential electrochemical mass spectrometry (DEMS) measurements of volatile reaction products. Batches of shape-selected Pt nanocrystals with different shapes and hence different surface structures were prepared and structurally characterized by transmission electron microscopy (TEM) and electrochemical methods. The potential for in situ spectro-electrocatalytic studies is illustrated for COad oxidation on Pt nanocrystal surfaces, where we could separate contributions from two processes occurring simultaneously, oxidative COad removal and re-adsorption of (bi)sulfate anions, and reveal a distinct structure sensitivity in these processes and also in the structural implications of (bi)sulfate re-adsorption on the CO adlayer. PMID:24991511

Brimaud, Sylvain; Jusys, Zenonas; Behm, R Jürgen

2014-01-01

303

Dynamic observations of the 8 January 2010 pyroclastic flow from the Soufriere Hills Volcano, Montserrat ascertained by high-definition and FLIR video analysis, as well as geometric analysis of the DEM  

NASA Astrophysics Data System (ADS)

On January 8th 2010, Soufriere Hills Volcano (Montserrat) experienced a collapse of the northwestern part of its andesitic lava dome. The ensuing explosive event lead to a 8.3 km high eruption column and generated a pyroclastic density current (PDC) that propagated down the northern flank of the volcano, moving down the Belham valley. This PDC was recorded from the Montserrat Volcano Observatory using both normal High- Definition and Forward Looking Infrared (FLIR) video cameras. The flow front velocity profile, plus the vertical motion of discrete buoyant thermals ascending above the PDC, were measured by combining the video data with a deposit map and a high spatial-resolution DEM. A theoretical treatment was then applied to extract key parameters that describe the buoyant motion of thermals ascending above the current (including density, particle mass volume fraction, and temperature). Interaction of the PDC with topographic features corresponded to important changes in the dynamics of the PDC as well as the ascent of the buoyant ash-clouds These interactions included an increase of the ascent rate of buoyant thermals when the PDC encountered topographic barriers, and deceleration of the flow front velocity due of high degrees of valley sinuosity. Additionally, a major change in flow dynamics was visible in our data 2 - 3 km from the dome. To investigate this further, channel slope, sinuosity, and cross-sectional area were measured from high-resolution DEMs using GIS software; and were compared to geometric parameters of the mapped ash-cloud surge deposits. The data illustrate three surge generation regimes: a proximal area of rapid lateral expansion; a medial deflation zone; and a steadier distal surge 'fringe'. These surge regimes relate directly the dramatic change in buoyant thermal flow dynamics observed 2-3 km from the dome and are also correlated with velocity and inversely correlated with valley cross-sectional area. Several possible origins can be proposed to explain this change, including changes in internal factors (i.e. degree of fluidization, sedimentation rate, and ash generation from block fragmentation) and/or external factors (influence of topographic barriers, changes in slope, sinuosity, valley-holding capacity). Complementary laboratory and dynamical observation would better constrain variations in the dynamics. Areas of topography-induced increases in velocity and inter-granular collisions are interpreted to result in more pervasive fluidization and thus enhanced surge generation. Distally, surge deposits appear as fringes with decaying extents, indicative of more passive expansion and decreasing velocity. The results indicate that surge mobility and detachment are a complex product of flow mass flux and topography and that future efforts to model dense-dilute coupled flows will need to account for and integrate several mechanisms acting on different parts of the flow.

Molle, A.; Ogburn, S. E.; Calder, E. S.; Roche, O.; Harris, A. J.

2012-12-01

304

Dem Bones: Forensic Resurrection of a Skeleton.  

ERIC Educational Resources Information Center

Presents an activity for students to determine the sex and age of an individual from a collection of bones. Simulates some of the actual procedures conducted in a forensic anthropologist's lab, examining and identifying bones through a series of lab activities. (Author/ASK)

Bruce, Alease

2001-01-01

305

Segregation in Rapid Flows: Continuum and DEM  

E-print Network

(e.g., fluid catalytic cracking unit) sand Saturn's rings asteroids lunar regolith biomass coal FCC catalyst #12;How do polydisperse flows differ from monodisperse? 1) Bulk flow behavior: solid") and instantaneous contacts (not enduring) · granular: role of interstitial fluid phase is negligible #12;Outline 1

Gruner, Daniel S.

306

Diesel Exhaust in Miners Study (DEMS)  

Cancer.gov

In March 2012, the National Cancer Institute (NCI) and the National Institute for Occupational Safety and Health (NIOSH) completed a retrospective cohort mortality and nested case-control study of 12,315 workers at eight non-metal mining facilities to investigate risk of lung cancer in relation to quantitative measures of historical exposure to diesel exhaust, after taking into account smoking and other lung cancer risk factors

307

Auf dem Weg zur prozessorientierten Patientenidentifikation  

Microsoft Academic Search

Wie in den meisten Branchen, sind auch im Gesundheitswesen die IKT-Lˆsungen ¸ber mehrere Jahre gewachsen. Eine heterogene Systemlandschaft ist die Folge. Eine zentrale Herausforderung stellt heute deswegen die organisationsinterne und organisations¸bergreifende Identifikation des Patienten dar. Obwohl eine Vielzahl technischer Hilfsmittel f¸r das Identit‰tsmanagement bereits zur Verf¸gung steht, scheitert die Umsetzung oftmals an der fehlenden Orientierung am Patientenprozess. In diesem Artikel

T. Mettler; P. Rohner

2008-01-01

308

Auf dem Weg zum universellen Quantencomputer  

NASA Astrophysics Data System (ADS)

Die Quantenmechanik eröffnet faszinierende Perspektiven für die Kommunikation und die Informationsverarbeitung. Um universell programmierbare Quantenrechner realisieren zu können bedarf es der Implementierung von Konzepten zur Quanteninformationsverarbeitung die sich auf eine große Anzahl von Qubits anwenden lassen.

Jaksch, Dieter; Calarco, Tommaso; Zoller, Peter

2000-11-01

309

Aus dem Inhalt ,,Willkommen zur besten Weihnachts-  

E-print Network

- Vorschlägen habe der des emeritierten Designprofessors Herbert Lindinger am meisten überzeugt. Gemeinsam mit Anna-Lena Lin- demann und der Moderator Sebastian Steinlechner die Zuschauerinnen und Zuschauer mit auf

Vollmer, Heribert

310

Die tibiotalare Arthrodese mit dem Kompressionsmarknagel  

Microsoft Academic Search

Objective Arthrodesis of the ankle joint in proper position (neutral position in respect to flexion\\/extension, 5° external rotation, 0–5° of valgus). Pain-free weight bearing of the affected limb. Indications Painful osteoarthritis of the ankle joint resistant to conservative approaches even in the presence of poor bone quality of the distal tibia such as after pilon fractures and osteoporosis. Failure of

Thomas Mückley; Gunther Hofmann; Volker Bühren

2005-01-01

311

Automatic DEM Generation Using Magellan Stereo Data  

NASA Technical Reports Server (NTRS)

The Magellan radar instrument collected a large volume of radar stereo images during its two years of operation. In order to make full use of this data an automatic means of generating digital elevation models is required. Because of Magellan's unique orbital geometry and radar image formation algorithm a number of modifications to the standard stereo processing scheme are required. This paper outlines a stereo algorithm suitable for Magellan data.

Hensley, S.; Shaffer, S.

1994-01-01

312

Fusionen auf dem Printmedienmarkt aus wirtschaftspolitischer Sicht  

Microsoft Academic Search

Printmedienmärkte weisen eine Reihe besonderer Eigenschaften auf, die sie von gewöhnlichen Produktmärkten unterscheiden. Die beiden wichtigsten dieser abgrenzenden Charakteristika sind (i) die direkte Abhängigkeit von Printmedienreichweite und Nachfrage nach Anzeigenseiten und (ii) die starke Fixkostendegression. Diese Arbeit zeigt aus wirtschaftstheoretischer Sicht, dass die Verbundenheit von Anzeigen- und Lesermarkt zu einer Reduktion der Anreize von Printmedienpreiserhöhungen im Fusionsfalle führt. Sie macht

Ralf Dewenter; Ulrich Kaiser

2005-01-01

313

Future earthquake source faults on deep sea-floor around the Boso triple plate junction revealed by tectonic geomorphology using 3D images produced from 150 meter grid DEM  

NASA Astrophysics Data System (ADS)

Boso triple junction, which is the only example of a triple trench junction on earth, is located off the southeast of Boso peninsula, where the Izu-Bonin trench meets with the Japan trench and the Sagami trench. Boso submarine canyon, which is extended to Katsuuma basin about 7000m deep, forms an incised meander along the north side of Sagami trough. Taito spur separate Katsuuma basin from Bando abyssal basin about 9000m deep, where Japan trench meet with Isu-Bonin trench. In this paper, we present detailed stereo-paired topographic images produced from 0.002 degree (about 150m) DBEM (Digital Bathymetry Model), which processed from the depth sounding data obtained by Japan Coast Guard and JAMSTEC around Boso triple junction. It enables us to observe submarine geomorphology easily and precisely. We identified submarine active faults and other tectonic features related to subduction by using the similar standard for air-photo interpretation of inland active faults. We made more precise submarine active tectonic geomorphological map around Boso triple junction than that by previous workers. Numerous distinct faults on the so-called outer rise associated with subduction of Pacific plate are regarded as normal faulting as widely accepted. While the normal faults on the outer rise are parallel to the trench in the southern part of the Japan trench and the northern part of the Izu-Bonin trench, these normal faults around the east of the triple junction with NNW-SSE extend slightly oblique to the trench. The western margin of Bando abyssal basin is bounded by the thrust faults, which form east-facing 200-500m-high convex scarps associated with raised basin floor to the west of the scarp. These faults also deform Mogi submarine fan surface and uplift to the west along the extension of the scarp. The antecedent valley is extended for about 10km across Taito spur that is an active anticlinal ridge about 1000m high. Katsuura basin is surrounded by terraced former basin floor that is tilted to the west, indicating up-growing of Taito spur. Northeastern part of Izu bar on Philippine Sea plate is characterized by rather smooth extensive convex slope between 1500m-7500m for over 200km long along the trench. On the lower part of the slope below 6000m, several gullies such as Mikura canyon and Kita-Hachijo canyon dissecting the slope forms rapids, probably due to continuous up-warping by subsurface thrusting dipping to the west under the slope. It is noteworthy that we can identify prominent active tectonic features on even very deep sea-floor along the plate boundaries, by using 3D images produced from 150 meter grid DEM.

Goto, H.; Nakata, T.; Watanabe, M.; Suzuki, Y.; Izumi, N.; Nishizawa, A.; Horiuchi, D.; Kido, Y. N.

2013-12-01

314

Floristische Beobachtungen aus dem östlichen Oberösterreich und dem angrenzenden Niederösterreich, Teil HI  

Microsoft Academic Search

Floristic records from eastern Upper Austria and the adjacent part of Lower Austria, Part ID New records of 100 rare vascular plant species are presented from eastern Upper Austria and the adjacent part of Lower Austria. Many of the species are aliens. The new localities are discussed with respect to relevant literature and the regional distribution of the species is

F. ESSL

315

Funde bemerkenswerter Gefaßpflanzenarten in den Mollner Kalkvoralpen, dem mittleren Steyrtal und dem oberen Kremstal (Oberösterreich)  

Microsoft Academic Search

Records of remarkable vascular plant species in the Mollner Kalkvoralpen, the middle Steyr valley and upper Krems valley (Upper Austria) New records of 58 rare vascular plant species of the upper Krems valley, the middle Steyr valley and the adjacent Upper Austrian limestone Alps are presented. The majority of the records was made during biotope mapping-projects of the area between

F. ESSL; C. H. EICHBERGER; K. HOLBER; C. H. JUSTIN; C. OTT; A. PÜRSTINGER; G. SCHNEEWEISS; P. SCHÖNSWETTER; M. STAUDINGER; O. STÖHR; A. TRIBSCH; B. TURNER

316

An application of the monetary approach to black market exchange rates  

Microsoft Academic Search

\\u000a Zusammenfassung  Eine Anwendung des monetÄren Ansatzes zur ErklÄrung von Schwarzmarkt-Wechselkursen. — Dieser Aufsatz entwickelt einen monetÄren\\u000a Ansatz zur Analyse der Schwarzmarkt-Wechselkurse unter besonderer Berücksichtigung Indiens. Der Gleichgewichtskurs auf solchen\\u000a MÄrkten wird in einem Modell durch die Bedingungen des Bestandsgleichgewichts bestimmt. Berücksichtigt wird dabei das mögliche\\u000a Zusammenwirken zwischen dem Schmuggel und dem Schwarzmarkt für Devisen. Die empirischen SchÄtzungen lassen vermuten, da? die

Sanjeev Gupta

1980-01-01

317

Versorgungsstruktur, Qualitätssicherung und klinische Studien beim invasiven Ovarialkarzinom in Deutschland — Aktionsprogramm QS-OVAR der AGO und Aktivitäten der AGO-Studiengruppe  

Microsoft Academic Search

Das Ovarialkarzinom ist unverändert die führende Todesursache bei den gynäkologischen Tumoren. Das Lebenszeitrisiko variiert\\u000a zwischen 1,1 und 1,6 in Europa und den USA (Parkin et al. 2002). Unter dem ICD-Code für maligne Ovarialtumoren verbergen sich so unterschiedliche Entitäten wie Keimzelltumoren, Stromazelltumoren,\\u000a Sarkome und epitheliale Tumoren. Legt man die amerikanischen Daten zugrunde, so sind 78,7% der malignen Ovarialtumoren invasive\\u000a Karzinome (Goodmann

A. Bois; J. Rochon; C. Lamparter; G. Elser; J. Pfisterer

318

Körperdysmorpher Wahn  

Microsoft Academic Search

In den aktuellen Klassifikationssystemen der WHO und der Amerikanischen Psychiatrischen Gesellschaft (APA) wird zwischen wahnhaften\\u000a und nichtwahnhaften Formen der körperdysmorphen Störung unterschieden. In der ICD-10 (Dilling et al. 1991) ist eine Zuordnung entweder zu den wahnhaften Störungen (F22.0) oder zur Hypochondrie (F45.2) vorgesehen. Beiden Krankheitsformen\\u000a gemeinsam ist eine intensive Beschäftigung mit dem eigenen Aussehen aus der Überzeugung heraus, missgestaltet zu

Dirk Schmoll

319

Zur Morphologie des Gynözeums von Berberis  

Microsoft Academic Search

Zusammenfassung An Hand abnorm dimerer Gynözeen vonBerberis vulgaris wird die Frage nach einer möglichen Pseudomonomerie desBerberis-Pistills neuerlich aufgeworfen. Der hier mögliche Vergleich zwischen sicheren Einzelkarpellen mit dem normalen Pistill ergibt aber einwandfrei, daß in beiden Organen die Bündel einander vollkommen entsprechen, daß also im normalen Gynözeum keine Restbündel eventuell eingeschmolzener Karpelle vorhanden sind und daß dieses Gynözeum somit echt monomer

Walter Leinfellner

1957-01-01

320

Verkndungsblatt 16|2008 Ausgabedatum 28.10.2008  

E-print Network

VG Dienstvereinbarung nach § 78 des Niedersächsischen Personalvertretungsgesetzes zwischen der Gottfried Wilhelm Leibniz Universität Hannover und dem Personalrat der Gottfried Wilhelm Leibniz Universität Hannover zum Einsatz der.uni-hannover.de/de/universitaet/veroeffentlichungen/verkuendungsblaetter/ #12;Verkündungsblatt der Gottfried Wilhelm Leibniz Universität Hannover vom 28.10.2008 16/2008 Die

Vollmer, Heribert

321

WS 2004/05 Uwe Franz Graphentheorie  

E-print Network

Preise: Nach: Merkur Venus Erde Mars Jupiter Saturn Uranus Neptun Pluto Von: Merkur 5 7 9 Venus 4 20 Erde 6 11 12 Mars 8 31 Jupiter 7 18 Saturn 11 14 Uranus 9 Neptun 13 13 Pluto 15 Z.B. kostet die Reise vom Merkur zur Erde 7 Solar-$ und von der Erde zum Merkur 6 Solar-$. Zwischen der Erde und dem Uranus gibt es

Schürmann, Michael

322

Magnetothermische untersuchungen an Cu-Al-Mn-legierungen (konzentrationsbereich der heusler-phase)  

Microsoft Academic Search

Ternäre Cu-Al-Mn-Legierungen mit konstantem Verhältnis Cu\\/Mn = 2\\/1 wurden im flüssigen und festen Zustand im Bereich zwischen dem Binärsystem Cu-Mn und nahezu reinem Al untersucht. Nach einer bestimmten Wärmebehandlung zeigen die Legierungen bei der Zusammensetzung Cu2MnAl (L21 Struktur, Heusler-Legierungen) bei Raum- temperatur maximale Magnetisierungswerte mit einer korrespondierenden Magnetonenzahl von nf = 3,5. Kühlt man diese Heusler-Legierung aus der Schmelze ab,

Ernst Wachtel; Franz Deissenrieder

1977-01-01

323

„Überholen ohne einzuholen“ Die Entwicklung von Technologien für übermorgen in Kernenergie und Mikroelektronik der DDR  

NASA Astrophysics Data System (ADS)

Dem nuklearen Patt zwischen Ostblock und westlichem Staatenbündnis ist es nach weitgehend übereinstimmender Auffassung von Politik und Wissenschaft zu danken, dass der "Kalte Krieg" in der zweiten Hälfte des 20. Jahrhunderts nicht zum weltumfassenden Flächenbrand eskalierte. An der raschen Herstellung dieses Patts waren zwei Dresdner Physiker maßgeblich beteiligt, deren einer im Manhattan-Projekt in den USA gearbeitet hatte und später in England der Spionage für die Sowjetunion und des Verrats des Know-how der Atombombe überführt wurde.

Barkleit, Gerhard

324

Zum Ablauf des Brutgeschäftes bei Enten  

Microsoft Academic Search

Zusammenfassung 1.Fortpflanzungszeit und anschließende Großgefiedermauser nehmen bei Enten über 100 Tage in Anspruch. Spät brütende Populationen können daher in Zeitdruck kommen.2.Im Ismaninger Teichgebiet (Oberbayern) liegt der Mittelwert des Legebeginns beiAnas platyrhynchos etwa Mitte Mai,Anas strepera Ende Mai,Aythya ferina Anfang Juni undA. fuligula nach dem 10. Juni (Tab. 1). Theoretisch hätten daher die ? im Mittel erst zwischen Ende August und

Einhard Bezzel; Eberhard von Krosigk

1971-01-01

325

Die Kumulation der galenischen Präparate aus Folia Digitalis purpurea und aus Folia Digitalis lanata, im Zusammenhang mit ihrem Gehalt an reinen Glykosiden  

Microsoft Academic Search

Zusammenfassung Die Kumulation der reinen Glykosidfraktionen aus Digitalis purpurea und aus Digitalis lanata wurde nach 2 Tagen bestimmt. Es zeigte sich, daß in Bezug auf diese Eigenschaft die Glykoside sich folgenderweise reihen lassen: 1. Lanatoxin, 2. Digitoxin, 3. Lanadigin, 4. Bigitalin, 5., 6. und 7.: Gitalin, Lanatalin und Glykosid IV.

R. A. Hoekstra

1932-01-01

326

Zwischen Europa und Amerika — Hannah Arendts Wanderungen durch die politische Ideengeschichte  

Microsoft Academic Search

\\u000a Abstract  This essay argues, that the path of Hannah Arendt, escaping the Hitler-regime, is reflected in a special mode in her trilogy\\u000a of political science. In the book on totalitarianism she would say good bye to the European modernity. But in “Vita activa”\\u000a she would turn back to the ancient greek origins of the political. And in her book on revolution

Alfons Söllner

2008-01-01

327

Untersuchungen über die Wechselwirkung zwischen Licht und Chemosynthese am Beispiel von Nitrobacter winogradskyi  

Microsoft Academic Search

1.In Nitrobacter winogradskyi, the influence of light on the respiratory chain enzymes, on oxidative phosphorylation and on CO2 fixation of whole cells was investigated by use of various methods. In addition, the effect of light on coupling reactions was studied.2.The spectral light sensitivity increases progressively from visible blue to ultra violet. The action spectrum is in accordance with the absorption

Eberhard Bock

1970-01-01

328

Fortpflanzungsbiologie der Kohlmeise Parus major auf kleinen Flächen: Vergleich zwischen einheimischen und exotischen Baumbeständen  

Microsoft Academic Search

In SW-Germany (Weinheim, 54.89 N; 34.76 E) some aspects of breeding biology of Great Tit were studied in forest patches with native versus exotic trees. Density of breeding pairs, breeding success, development of nestlings, food supply and foraging behaviour of feeding adults were compared between five patches with native and ten patches with exotic trees. Clutch size, hatching and fledging

Harald Kolb

1996-01-01

329

Nationalismus im Sonderangebot - Coca-Cola-Werbung zwischen Lifestyle Kreation und politischer Mythenbildung  

Microsoft Academic Search

Nationalism in the sense of symbols or actions glorifying the fatherland can be detected in many Chinese commercials today. In the form of a mythical narration, various aspects of an idealized China image are communicated, an image designed to bring about a sense of identity for all Chinese people. While first and foremost serving consumer pref- erences, these emotionally charged

Nora Frisch

2009-01-01

330

Zur Lokalisierung von Zellkontakten zwischen Cuscuta odorata und verschiedenen höheren Wirtspflanzen  

Microsoft Academic Search

Zusammenfassung Es wird eine Methode der gezielten Untersuchung von parasitierendenCuscuta-Hyphen innerhalb des Wirtsgewebes (Pelargonium zonale, Primula obconica) beschrieben. Das Arbeiten mit isolierten Leitbündeln (Primula) sowie eine verfeinerte Zielpräparation der fixierten und eingebetteten Gewebe vor der Ultramikrotomie führt bereits mit lichtoptischen Methoden zu einer zellularen Lokalisierung der Hyphen im Wirtsgewebe. Diese wiederum ermöglicht eine genaue Beurteilung des Differenzierungsstadiums der Parasitenzellen vor

Inge Dörr

1968-01-01

331

Über den Wirkungsmechanismus des Ephedrins und den Unterschied in der Wirkungsstärke zwischen seinen Isomeren  

Microsoft Academic Search

Zusammenfassung 1.Die Blutdruckwirkung des Ephedrins ist nicht als Herzwirkung aufzufassen. Sie ist eine rein periphere Gefäßwirkung und kommt dadurch zustande, daß durch das Ephedrin die Gefäße für Suprarenin sensibilisiert werden. An und für sich unwirksame Ephedrinkonzentrationen verursachen an den mit verdünnten Suprareninlösungen durchströmten Froschgefäßen eine starke, langanhaltende Vasokonstriktion.2.Mit derselben Methode lä\\\\t sich auch die sensibilisierende Wirkung des Kokains und die

Otto Schaumann

1928-01-01

332

Comparison of a 3-D DEM simulation with MRI data  

NASA Astrophysics Data System (ADS)

This paper presents a comparison of a granular material studied experimentally and numerically. Simple shear tests were performed inside the magnetic core of magnetic resonance imaging (MRI) equipment. Spherical pharmaceutical pills were used as the granular material, with each pill's centre location determined by MRI. These centre locations in the initial assembly were then used as the initial configuration in the numerical simulation using the discrete element method. The contact properties between pharmaceutical pills used in the numerical simulation were obtained experimentally. The numerical predication was compared with experimental data at both macroscopic and microscopic levels. Good agreement was found at both levels.

Ng, Tang-Tat; Wang, Changming

2001-04-01

333

7.5-Minute Digital Elevation Model (DEM)  

NSDL National Science Digital Library

The US Geological Survey (USGS) performs a wide variety of tasks related to the environment including data acquisition for use in geographical information systems. This data set provides elevation data for the contiguous US, Hawaii, and Alaska. Data are in one-by-one degree blocks and available via an online interface or by ftp download (instructions provided in the User Guide). Specific data can be located via alphabetical list, state, or a graphic of the US.

334

DEM Solutions Develops Answers to Modeling Lunar Dust and Regolith  

NASA Technical Reports Server (NTRS)

With the proposed return to the Moon, scientists like NASA-KSC's Dr. Calle are concerned for a number of reasons. We will be staying longer on the planet's surface, future missions may include dust-raising activities, such as excavation and handling of lunar soil and rock, and we will be sending robotic instruments to do much of the work for us. Understanding more about the chemical and physical properties of lunar dust, how dust particles interact with each other and with equipment surfaces and the role of static electricity build-up on dust particles in the low-humidity lunar environment is imperative to the development of technologies for removing and preventing dust accumulation, and successfully handling lunar regolith. Dr. Calle is currently working on the problems of the electrostatic phenomena of granular and bulk materials as they apply to planetary surfaces, particularly to those of Mars and the Moon, and is heavily involved in developing instrumentation for future planetary missions. With this end in view, the NASA Kennedy Space Center's Innovative Partnerships Program Office partnered with OEM Solutions, Inc. OEM Solutions is a global leader in particle dynamics simulation software, providing custom solutions for use in tackling tough design and process problems related to bulk solids handling. Customers in industries such as pharmaceutical, chemical, mineral, and materials processing as well as oil and gas production, agricultural and construction, and geo-technical engineering use OEM Solutions' EDEM(TradeMark) software to improve the design and operation of their equipment while reducing development costs, time-to-market and operational risk. EDEM is the world's first general-purpose computer-aided engineering (CAE) tool to use state-of-the-art discrete element modeling technology for the simulation and analysis of particle handling and manufacturing operations. With EDEM you'can quickly and easily create a parameterized model of your granular solids system. Computer-aided design (CAD) models of real particles can be imported to obtain an accurate representation of their shape. EDEM(TradeMark) uses particle-scale behavior models to simulate bulk solids behavior. In addition to particle size and shape, the models can account for physical properties of particles along with interaction between particles and with equipment surfaces and surrounding media, as needed to define the physics of a particular process.

Dunn, Carol Anne; Calle, Carlos; LaRoche, Richard D.

2010-01-01

335

Kafka's "Vor dem Gesetz": The Case for an Integrated Approach  

ERIC Educational Resources Information Center

Uses a parable from a Kafka novel to illustrate and support the premise that language and literature study should be integrated, even in the early stages. Reading short literary works can explain involved language problems better than long explanations, and can also stimulate further literary study. (CHK)

Pickar, Gertrud Bauer

1975-01-01

336

"Dem Wod Mo Saf": Materials for Reading Creole English.  

ERIC Educational Resources Information Center

As part of a study that sought ways to improve the language arts educational experience for Grenadian children, an anthropologist investigated how Carriacou Creole English (CCE) reading materials could be provided and how these children would react to them. CCE is the native language of the inhabitants of Carriacou, a sister island of Grenada. The…

Kephart, Ronald

337

ASSEMBLING DEM FILES FOR WATERSHED ANALYSIS. (R826595)  

EPA Science Inventory

The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

338

Case Study: Dem Bones - Forensic Resurrection of a Skeleton  

NSDL National Science Digital Library

This is a case study for high school and undergraduate students in anatomy and physiology. In particular this case study explores anatomy of the skeleton (including landmarks), sex and age determination via pelvic and skull morphology. Users of the National Center for Case Study Teaching in Science will be required to register (free) to gain access to the answer key (and must be of teaching status to receive the key). Included in the resource are the case overview, objectives, case study, teaching notes and answer key.

Alease S. Bruce (University of Massachusetts-Lowell Department of Health and Clinical Sciences)

2001-07-09

339

Natural Neighbor Interpolation Based Grid DEM Construction Using a GPU  

E-print Network

data into useful information for vastly different types of users requires solving several challenging Science Foundation. Permission to make digital or hard copies of all or part of this work for personal are constructed for a water level of 2 meters, it looks as if most of the island will be underwater; see Figure 1

Agarwal, Pankaj K.

340

Homogeneity and Symmetry in DEM Models of Cone Penetration  

NASA Astrophysics Data System (ADS)

A three—dimensional numerical model was implemented to PFC3D Code to simulate cone penetration test in Ticino sand in a calibration chamber. The model is calibrated using laboratory test results. The full/half/quarter calibration chamber was used to examine the effect of symmetry on the results. Examination of specimen homogeneity was done by (i) visual observation of the network of the contact forces developing between particles, (ii) examination of the porosity, d50 and Cu distributions inside the specimen by using a representative elementary volume (REV). Some overall results from these simulations are also presented here and compared with the experimental results from a calibration chamber test database.

Butlanska, Joanna; Arroyo, Marcos; Gens, Antonio

2009-06-01

341

Charakterisierung des Plasmamembranproteoms aus dem olfaktorischen Epithel von Mus musculus.  

E-print Network

??Für das Verständnis der Abläufe im olfaktorischen System sind Kenntnisse über die Proteinzusammensetzung der Plasmamembran (PM) eine wichtige Voraussetzung. Im Rahmen dieser Arbeit wurde erstmalig… (more)

Adler, Jenny

2009-01-01

342

Zur Theorie der Manganate Auf dem Weg zu neuer Elektronik  

E-print Network

wissenschaftliche Abhandlung 1600 von Sir William Gilbert heute: kollektive Anordnung von Elektronenspins trotz in China erste wissenschaftliche Abhandlung 1600 von Sir William Gilbert heute: kollektive Anordnung von

Peters, Achim

343

FORTSCHRITTE AUF DEM GEBIET DER HONIGTAU-FORSCHUNG  

E-print Network

the honeydew from only few (58 known) species of Ster- norrhyncha (coccids, aphids, psyllids) (Table 1. As a consequence, these aphids secret 2-3 times more honeydew with 25-40% dry weight sucrose (from coccids and aphids) instead of less than 1 % sucrose found from aphids without a filter - gut. The appearance

Paris-Sud XI, Université de

344

Leibniz und Hannover dem Universalgenie auf der Spur  

E-print Network

Universalgenie auf der Spur Leibniz war überzeugt: Honovere hei�t hohes Ufer. #12;4 5 Gottfried Wilhelm Leibniz überhaupt und Teil des Weltdokumentenerbes der UNESCO, von der Gottfried Wilhelm Leibniz Bibliothek Hannover-1784) Kupferstich von Martin Bernigeroth Gottfried Wilhelm Leibniz hat in Hannover Spuren hinterlassen. Mehrere

Vollmer, Heribert

345

Neue Daten zur Flora von Wien, Niederösterreich und dem Burgenland  

Microsoft Academic Search

New or rediscovered (*) taxa are presented for the flora of Vienna (Alyssum hirsutum, Carex divisa*, Cerastium lenoreanum*, Herniaria incana, Panicum miliaceum subsp. ruderale and Rubus laciniatus), for Lower Austria (Cotoneaster bullatus (!), C. dammeri, C. divaricatus (!), Elymus hispidus subsp. barbulatus x E. repens subsp. repens (!) and Ferulago galbanifera*), for Bureenland (Althaea cannabina, Duchesnea indica. Echinochloa crus-galli subsp.

H. MELZER

346

DEM Simulation of Rock Shed Failure due to Rockfall Impact  

NASA Astrophysics Data System (ADS)

The rock shed is a more costly but effective traffic facility used to keep out falling rocks in Taiwan. The main function of rock shed is to let the falling rock passing through via the top slab without hitting the road users. The failure mode of the rock shed due to rockfall impact generally includes punching of top slab, flexural cracks of beam, buckling of column, and damage of foundation, etc. Even so, the failure behavior of the rock shed is still complicated and difficult to predict. Accordingly, this study adopts the discrete element program (PFC2D) to simulate the failure behavior of rock shed. A comparison with uniaxial compression test was carried out firstly to determine the micro parameters of structure elements. The model was utilized to simulate the behavior of rock shed with impact load or hitting of falling block separately. Then, a case study of present rock shed of highway NO.18 in middle Taiwan was analyzed. The result indicates that: the primary causes of rock shed failure mode include block size, falling height, impact position, and structure system. The failure mode of punching shear failure or flexural cracks is dominated by block size and falling height. The occurrence of differential settlement is related to impact position and absence of combined footing. Considering the connection of beam and column, the structure is more likely to break at the joints rather than punching of the top slab. As a result, combined footing and beam-to-column joint should be to take into account to obtain safer protection of rock shed. Keywords: rockfall disaster, PFC, rock shed, discrete element method

Chen, Jian-An; Lin, Ming-Lang; Wang, Ching-Ping; Lo, Chia-Ming

2013-04-01

347

Two Preliminary SRTM DEMs Within the Amazon Basin  

Microsoft Academic Search

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

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

2002-01-01

348

Forecasting of Storm Surge Floods Using ADCIRC and Optimized DEMs  

NASA Technical Reports Server (NTRS)

Increasing the accuracy of storm surge flood forecasts is essential for improving preparedness for hurricanes and other severe storms and, in particular, for optimizing evacuation scenarios. An interactive database, developed by WorldWinds, Inc., contains atlases of storm surge flood levels for the Louisiana/Mississippi gulf coast region. These atlases were developed to improve forecasting of flooding along the coastline and estuaries and in adjacent inland areas. Storm surge heights depend on a complex interaction of several factors, including: storm size, central minimum pressure, forward speed of motion, bottom topography near the point of landfall, astronomical tides, and most importantly, maximum wind speed. The information in the atlases was generated in over 100 computational simulations, partly by use of a parallel-processing version of the ADvanced CIRCulation (ADCIRC) model. ADCIRC is a nonlinear computational model of hydrodynamics, developed by the U.S. Army Corps of Engineers and the US Navy, as a family of two- and three-dimensional finite element based codes. It affords a capability for simulating tidal circulation and storm surge propagation over very large computational domains, while simultaneously providing high-resolution output in areas of complex shoreline and bathymetry. The ADCIRC finite-element grid for this project covered the Gulf of Mexico and contiguous basins, extending into the deep Atlantic Ocean with progressively higher resolution approaching the study area. The advantage of using ADCIRC over other storm surge models, such as SLOSH, is that input conditions can include all or part of wind stress, tides, wave stress, and river discharge, which serve to make the model output more accurate.

Valenti, Elizabeth; Fitzpatrick, Patrick

2005-01-01

349

Über die Untersuchung von Haaren mit dem Rasterelektronenmikroskop  

Microsoft Academic Search

Summary The report deals with the application of the scanning electron microscope to forensic investigations carried out on hair. In particular, attention is paid to the cuticular characteristics of human hair in relation to age and origin (part of the body) as well as of animal hair in relation to the species of animal and location. In addition examples of

Volkmar Schneider

1972-01-01

350

Enossale Implantatversorgung von Tumorpatienten mit dem Bone-Lock-System  

Microsoft Academic Search

Zusammenfassung Die implantologische Versorgung von Patienten nach ablativer Tumorchirurgie und Defektrekonstruktion erfolgt meist abseits strenger Maßstäbe der Erfolgsbeurteilung. Deshalb untersuchten wir die von Juni 1990 bis Juni 1996 bei 58 Tumorpatienten enoral gesetzten 210 Implantate regelmäßig nach. Verwendung fand ausschließlich das enossale Bone-Lock-Implantatsystem (Howmedica Leibinger GmbH, Freiburg). Untersucht wurden der Plaqueindex (Silness und Löe), der Sulkusblutungsindex (Löe), die Sondierungstiefe, die

A. Kovács; Johann Wolfgang

1998-01-01

351

Multiscale curvatures for identifying channel locations from DEMs  

NASA Astrophysics Data System (ADS)

Curvature based methods are suitable for channel identification in digital elevation models. One obstacle in using these methods is the fact that channels generally occur at multiple scales in the landscape, from small creeks to large rivers. In this paper, we show how likely channel pixels can be identified simultaneously at a range of scales using multiscale curvature operators applied to digital elevation models. Our proposed Hyperscale Channel Extraction (HCE) method localizes channels at the smallest scale while simultaneously tracking the shape of the channel at a full interval of scales (the hyperscale). We test the method using two different types of curvature, and apply and validate it to a catchment representing terrain with a high slope sampled by airborne laser altimetry. The test results demonstrate that by explicitly employing the extra dimension of scale to localize channels, (a) we are able to robustly identify channel pixels, as possible channel locations are tracked through a full interval of scales, (b) no more a priori determination of the relevant scale is necessary, and (c) only one parameter remains to be set: a threshold on the curvature value that has a clear physical interpretation.

Koenders, R.; Lindenbergh, R. C.; Storms, J. E. A.; Menenti, M.

2014-07-01

352

DEM based simulation of concrete structures on GPU  

E-print Network

of rock im- pact on a concrete slab, before to discuss the pro and cons of moving such computation of severe dynamic loadings due to natural or anthropogenic hazards such as rock falls, aircraft or missile., 2010) impacted by large projectile like an aircraft, the size of the area that is represented by DEs

Paris-Sud XI, Université de

353

Aus den Augen, aus dem Sinn… — Die Pflanzenreste aus dem mittelalterlichen Abwasserkanal der Grabung Am Hof 10, Wien 1  

Microsoft Academic Search

Archaeobotanical analysis of the filling of a medieval sewage drain in the 1st district in Vienna (excavation “Am Hof 10”) resulted in a large amount of plant remains, predominantly 1,172 grapevine (Vitis vinifera subsp. vinifera) pips and their fragments. Among the cultivated cereals, barley (Hordeum vulgare), emmer (Triticum dicoccum), spelt (Triticum spelta), and broomcorn millet (Panicum miliaceum) were unequivocally identified,

Andreas G. Heiss; Ursula Thanheiser

2013-01-01

354

Market efficiency, purchasing power parity, and black markets: Evidence from latin american countries  

Microsoft Academic Search

\\u000a Zusammenfassung  Markteffizienz, KaufkraftparitÄt und SchwarzmÄrkte: Evidenz aus lateinamerikanischen LÄndern. - Die Arbeit verwendet den von\\u000a Rogalski\\/Vinso und Roll entwickelten theoretischen Rahmen, um das Verhalten der WÄhrungen von Kanada und den USA sowie von\\u000a ausgewÄhlten lateinamerikanischen LÄndern auf dem dortigen Schwarzmarkt zu untersuchen. Abweichungen von der KaufkraftparitÄt\\u000a werden analysiert, ebenso die Beziehungen zwischen diesen Abweichungen, den Wechselkursen und Inflationsdifferentialen, um\\u000a die Vereinbarkeit

Peter E. Koveos; Bruce Seifert

1986-01-01

355

Ressourcenaufteilung zwischen der oligolektischen Blattschneiderbiene Megachile lapponica L. (Hymenoptera, Apiformes) und anderen Blütenbesuchern am schmalblättrigen Weidenröschen (Epilobium angustifolium, Onagraceae)  

Microsoft Academic Search

Resource partitioning between the oligolectic leafcutter bee Megachile lapponica (Hymenoptera, Apiformes) and other visitors on flowers of Epilobium angustifolium (Onagraceae). In a clear-felling in the Kottenforst (Bonn) we registered the abundance of flower visiting insects on Epilobium angustifolium and observed their behaviour during flower visits. The most frequent bees on the flowers were Megachile lapponica, an oligolectic bee on Epilobium,

J. Kühn; A. Hamm; M. Schindler; D. Wittmann

356

Der Padagogische Umgang mit dem weltanschaulich-religiosen Pluralismus auf dem Prufstein (A Touchstone for the Pedagogical Approach to Ideological-Religious Pluralism).  

ERIC Educational Resources Information Center

Examines the model for ethical-religious instruction introduced in Brandenburg (Germany) from a constitutional and structural-pedagogical viewpoint. Points to problems with both the proposed "uniform" and "plural" models: the first infringes on minorities' interests and the second presupposes a high degree of cooperation between churches and state…

Nipkow, Karl Ernst

1996-01-01

357

Radiochirurgie mit dem Gamma Knife-System zur Sekundärtherapie der persistierenden Akromegalie.  

E-print Network

??Charakteristisch für das Krankheitsbild der Akromegalie sind eine pathologisch erhöhte Sekretion des Wachstumshormons (STH) im Erwachsenenalter und dadurch bedingte metabolische und morphologische Auswirkungen. In 99%… (more)

Alexandrov, Rumen

2004-01-01

358

FEM-DEM Simulation of Two-way Fluid-Solid Interaction in Fibrous Porous Media  

E-print Network

belts, modern engineering materials like composite materials, or geotechnical/physical systems [1. Srivastava and S. Luding Multi Scale Mechanics (MSM), MESA+ Institute for Nanotechnology, Faculty properties; Microstructure; Porous media; Drag force PACS: 47.11.Fg; 74.25.F; 61.72.-y; 47.56.+r INTRODUCTION

Luding, Stefan

359

Combining ICESat altimetry and SPIRIT SPOT5 DEMs to detect recent elevation changes of Svalbard glaciers  

Microsoft Academic Search

Estimation of recent glacier elevation changes in Svalbard is dependent upon the availability and overlap of geodetic data within the past decades. The ICESat altimeter has been a semi-continuous provider of elevation data between 2003 and 2008, though repeat track ICESat comparisons over rugged glacier terrain, like Svalbard, is complicated due to the unknown cross track slope. We test two

G. Moholdt; C. Nuth; A. Kääb; J. Kohler

2009-01-01

360

"Mit dem Autoschwimmbad in die Verkehrsmarmelade: Learning To Use Bilingual Dictionaries Successfully.  

ERIC Educational Resources Information Center

Introduces activities designed to wean students from equivalency thinking in the German as a foreign language classroom. Suggests that with sufficient prior linguistic awareness and some target language knowledge, use of a bilingual dictionary--in book form or on a computer--can become a successful learning experience. (Author/VWL)

Barbe, Katharina

2001-01-01

361

Political Participation of Non-Citzens in Germany and Western Europe. (Beitrage aus dem Fachbereich Padagogik).  

ERIC Educational Resources Information Center

This paper compares the present social, economic, and political rights labor immigrants enjoy within the European Community (EC). Its focus is the current debate about the municipal suffrage of permanent residents. The dual relevance of the topic is obvious. EC bodies like the Commission, Council of Ministers, Political Council, and European…

Reuter, Lutz R.

362

Das Spiel mit dem Rollenspiel (The Game with Role-Playing)  

ERIC Educational Resources Information Center

Maintains that role-play should not become the pre-eminent method in foreign language teaching, since it does not reach the broad goals of learning, such as the systematic acquisition of language material, achievement measuring, or the expression of personal views of many participants in adult education (Text is in German.) (IFS/WGA)

Hohmann, Heinz-Otto

1977-01-01

363

Dinner with "maTHEMATICs": in HonOUR of DemYstifyING Mathematics  

ERIC Educational Resources Information Center

Mathematics as a field of study is often encountered in its written form, captured in texts of various genres at primary and (post)secondary school levels. The way mathematics is WRITTEN (being referred to here as wrotographic evidence) determines to a greater extent how it is read and spoken (verbalized). This exploratory article has poetic…

Mwakapenda, Willy

2010-01-01

364

Unterrichtsversuche mit dem franzosischen Chanson (Instruction Experiments with the French Song)  

ERIC Educational Resources Information Center

Five teaching experiments with French songs, in grades 7, 8 and 9, are described. Aural understanding was practiced first, then use of the text. In the 9th grade, work on the content became most important, with the aim of correcting and expanding the common conception of France. (Text is in German.) (IFS/WGA)

Overbeck-Bollnow, Renate

1974-01-01

365

A First-Day "Realia" Activity: "Was ist in dem Umschlag?"  

ERIC Educational Resources Information Center

The first day of class is in many ways the most important one of the term. Students come into the classroom alert to everything around them, eager to piece together clues that will answer their ill-defined yet urgent question: "What is this course going to be like?" What teachers say and do on the first day of class is crucial, creating a first…

Bjornstad, Jennifer I.

2004-01-01

366

["Simulanten des Irrsinns auf dem Vortragspult": dada, war and psychiatry--'active dynamics of trauma'].  

PubMed

This paper relates stage performances of dada artists to war neurosis and shell shock as sociocultural phenomena. The leitmotif of this investigation is the notion of simulation, as dada artists were referred to as malingerers (simulators) of madness by the press at the time. I hypothesize that the performers imitate/simulate with drums, shouting and 'bruitist' sound poems, the noises of war, staging themselves as war neurotics in a kind of shocking clinical demonstration. Both discourses intersect in the fact that many dadaists try to dodge the draft by simulating madness. The scandalizing anti-art of dada will be understood as contagious anti-pedagogy, trying to vaccinate against the madness of the era. PMID:25671968

2014-12-01

367

"Doch ein Begriff muss bei dem Worte sein": Some Thoughts on Electronically Annotated Literary Texts.  

ERIC Educational Resources Information Center

Discusses the use of electronic glossaries, annotated texts, and other ancillae in German-as-a-Second-Language courses at the college level, and asserts that electronic media deliver lexical assistance far more effectively than do traditional methods, using texts in ways previously unavailable. (MDM)

Duncan, Bruce; Foelsche, Otmar K. E.

1995-01-01

368

Von den Weltkriegen nach Rom: Ideen und Stationen auf dem Weg zur EWG  

Microsoft Academic Search

\\u000a Seit den 1860er Jahren sorgte eine wachsende wirtschaftliche Verflechtung Europas für ein Fortschreiten der faktischen Integration.\\u000a Einer der wichtigsten Theoretiker dieser Integration um einen franzö-sisch-britischen-deutschen Kern war der englische Philosoph\\u000a Herbert Spencer (1820–1903; A System of Synthetic Philosophy, 1855–1896). Diese faktische Integration wurde von verschiedenen sozialen Gruppen\\u000a mitgetragen, deren Identität aus nationalen, aber ebensosehr aus internationalen und europäischen Elementen zusammengesetzt

Wolfgang Schmale

369

MURGANGAKTIVITT AUF EINEM BEWALDETEN KEGEL DER SCHWEIZER ALPEN SEIT DEM SPTEN HOLOZN  

E-print Network

on the forested cone of the Ritigraben torrent (Valais, Swiss Alps) allowed reconstruction of 123 debris torrent. In contrast, very low activity is observed for the last 10 years with only one debris-flow event

Stoffel, Markus

370

Proprocessing: Geocoding of AVIRIS Data Using Navigation, Engineering, DEM, and Radar Tracking System Data  

NASA Technical Reports Server (NTRS)

Remotely sensed data have geometric characteristics and representation which depend on the type of the acquisition system used. To correlate such data over large regions with other real world representation lools like conventional maps or Geographic Information Systems (GIS) for verification purposes, or for further treatment within different data sets, a coregistration has to be performed.

Meyer, P.; Larson, S. A.; Hansen, E. G.; Itten, K. I

1993-01-01

371

ALLE MACHT DEM VOLK? DAS DIREKTDEMOKRATISCHE INSTRUMENT ALS CHANCE FÜR DAS POLITISCHE SYSTEM JAPANS  

Microsoft Academic Search

The use of referendums and initiatives is generally increasing worldwide. In Japan referendums have been held since the mid-1990s. Nowadays, referen- dums are becoming popular among Japanese local citizen activists, but neverthe- less the position of referendums as an instrument of policy-making in the Japanese state is still weak. This weakness has its reasons not only in a lack of

Gabriele Vogt

372

IntroductIon The structure and composition of avian communities dem-  

E-print Network

, Cotton 2006, Craig & Hulley 1994, De Swardt 1991, Franklin & Noske 1999, Skead 1967, Symes et al. 2001. (Craig & Hulley 1994, Craig & Simon 1991, Skead 1967, Symes et al. 2001); Gurneys Sugarbird Promerops & Louw 1994, Symes et al. 2001); and the Cape sugarbird P. cafer which according to Fraser & Mc

de Villiers, Marienne

373

Ecology and behavior of reintroduced Hawaiian Geese Von dem Fachbereich Biologie  

E-print Network

of Forestry and Wildlife, the National Biological Survey, and Sandy and Jill Friedman, Honolulu, for financial and Susanne StrauÃ? were of invaluable assistance. My work on the State-wide database was only possible through

Black, Jeff

374

DEM SIMULATION OF MILL CHARGE IN 3D VIA GPU COMPUTING *R.K.Rajamani1  

E-print Network

for lifter design, power draft evaluation, etc. Both two-dimensional and three-dimensional codes are being used. The two-dimensional code dominates the user market since the code completes a simulation in one or two hours. On the other hand, three-dimensional codes have been in the domain of specialists who can

Callahan, Steven

375

Effektive oberflächennahe Erdwärmenutzung mit dem Geothermal Radial Drilling (GRD)Verfahren  

E-print Network

Effective Geothermal Utilisation close to the surface by the TT-Geothermal Radial Drilling (GRD-)Method In the late 1970-Years, Tracto-Technik developped a very effective radial-shaped percussion system for a geothermal heating, the ECOtherm-System, which was very well accepted by customers. Nowadays, a radial-shaped drilling system, operating some decameters below the surface, was developped by Tracto-Technik, which offers the chance of a very effective drilling for the use of geothermal energy. The main advantage of this development is the reduction of drilling costs by new constructions and new handling possibilities. Drilling processes like the rod connecting or the drill-hole enlargement were solved in other ways as usual, by very timeshortening and effective ways, which are presented in the paper. The new TT-Geothermal radial drilling methods need only a very small but highly effective drilling unit, which reduces the operational drilling cost in a enormous way. All operational drilling steps are reduced to less than a half time as usual. By these GRD-methods, the use of surface-close geothermal energy is simplified and less expansive.

Hans-joachim Bayer

376

Zur Anverwandlungsgeschichte eines Textes aus dem Corpus Hippocraticum in der Renaissance  

Microsoft Academic Search

\\u000a Abstract  The letters in the Hippocratic corpus that narrate the fictitious encounter between Hippocrates and Democritus met with exceptional\\u000a attention in the Renaissance. This article describes their reception as reflected in its textual history from the first Latin\\u000a version by Rinuccio d’Arezzo through the commentaries by Alaard of Amsterdam and Marcellin Bompart. It then highlights one\\u000a aspect of their intrepretative history

Thomas Rütten

1994-01-01

377

Assessment of an ASTER-generated DEM for 2D hydrodynamic flood modeling  

Microsoft Academic Search

Flood modeling often provides inputs to flood hazard management. In the present work we studied the flooding characteristics in the data scarce region of the Lake Tana basin at the source of the Blue Nile River. The study required to integrate remote sensing, GIS with a two-dimensional (2D) module of the SOBEK flood model. The resolution of the topographic data

Tesfaye Haimanot Tarekegn; Alemseged Tamiru Haile; Tom Rientjes; P. Reggiani; Dinand Alkema

2010-01-01

378

Globalität und Einheit- lichkeit mit Integrations- lösungen - auf dem Wege zum Wissensmanagement  

Microsoft Academic Search

Factiva, a Dow Jones and Reuters company, has its focal point in international news and in company information. The products of Factiva reach from a Web based research service (Factiva.com) to systems installed in knowledge management resp. customer relationship management (Factiva Fusi- on). Although including thousands of databases in different languages Factiva is an integrating retrie- val system with uniform

Wolfgang G. Stock

2003-01-01

379

Drug-eluting microspheres transarterial chemoembolization (DEM TACE) in patients with liver metastases. Pilot study  

PubMed Central

Summary Background: Only 10 to 20% of patients with hepatic metastases qualify for radical resection of their lesions. The treatment issue among the rest of patients is a small clinical response to overall chemiotherapy and the frequent inability to treat patients with percutaneous thermoablation. In the latter circumstance, parallel to the radical surgery, the reason is the size of the lesion or lack of access to it. Material/Methods: 15 patients with hepatic metastases, who had been rejected from consideration of radical resection and thermoablation were subjected to chemoembolization of the proper hepatic artery branches. The procedure was performed using Hepasphere 50–100 ?m impregnated with 100 mg of Doxorubicine. The primary tumor sites included: colorectal ca, cholangiocarcinoma, gastrinoma, gallbladder ca, pancreatic ca, GIST, lung ca, kidney ca, breast ca and larynx ca. The evolution of the disease was monitored by MRI scanning, which was performed after a mean time of 7.6 weeks from the chemoembolization. During the study, we compared patients’ quality of life (using Edmonton Evaluating System); length of hospital stay, chemoembolization side effects, and remission or progression of the disease by the RECIST 1.1 scale. Results: 26.7% of patients had remission of the metastatic disease, 33.4% experienced stable desease and 26,7% suffered lesion progression. Two patients did not report to the MRI examination. Chemoembolzation’s side effects were small and the quality of patients’ live improved. Effectiveness depended on the overal condition of the patient, and the stage of the primary disease. Conclusions: Chemoembolization is a minimally invasive, safe and possibly effective palliative procedure in patients with hepatic metastases. Further investigation on a larger group of patients is required and will be continued. PMID:22802838

Jarz?bek, Magdalena; Jargie??o, Tomasz; Wolski, Andrzej; Poluha, Pawe?; Szczerbo-Trojanowska, Ma?gorzata

2011-01-01

380

Automatic DEM Generation from CE-1's CCD Stereo Camera Images  

NASA Astrophysics Data System (ADS)

The goal of the CCD Stereo Camera is to acquire 3D-images of lunar surface bewteen 70S and 70N. We describe the process of the images acquired, configuration of imaging system, camera sensor model, camera trajectory model and EFP photogrammetric triangulation algorithm.

Liu, J. J.; Ren, X.; Mu, L. L.; Zhao, B. C.; Xiangli, B.; Yang, J. F.; Zou, Y. L.; Zhang, H. B.; Lu, C.; Liu, J. Z.; Zuo, W.; Su, Y.; Wen, W. B.; Bian, W.; Zou, X. D.; Li, C. L.

2009-03-01

381

TerraSAR-X and TanDEM-X: Revolution in spaceborne radar  

Microsoft Academic Search

Commercially available imagery is and will remain indispensable to civilian and military organizations gathering various types of geo-spatial information. Whether fulfilling international agreements, providing military contingents in international peacekeeping or humanitarian missions, or conducting joint technical exercises with other countries - a reliable access to timely, high resolution remote sensing data is an essential basis for well-informed decision making, particularly

N. Faller; M. Weber

2007-01-01

382

TerraSAR-X Instrument Calibration Results and Extension for TanDEM-X  

Microsoft Academic Search

Spaceborne remote sensing with synthetic aperture radar (SAR) has become an essential source of high-resolution and continuous Earth observation. Modern satellites like the German TerraSAR-X system provide state-of-the-art radar images with respect to operating flexibility and imaging quality. The outstanding performance of TerraSAR-X image products is achieved by an innovative calibration approach that minimizes systematic antenna and instrument characteristics. The

Benjamin Brautigam; Jaime Hueso Gonzalez; Marco Schwerdt; Markus Bachmann

2010-01-01

383

Mapping of debris-covered glaciers in the Garhwal Himalayas using ASTER DEMs and thermal data  

Microsoft Academic Search

Mapping of debris-covered glaciers using remote-sensing techniques is recognized as one of the greatest challenges for generating glacier inventories and automated glacier change analysis. The use of visible (VIS) and near-infrared (NIR) bands does not provide sufficient continual information to detect debris-covered ice with remote-sensing data. This article presents a semi-automated mapping method for the debris-covered glaciers of the Garhwal

R. Bhambri; T. Bolch; R. K. Chaujar

2011-01-01

384

A DEM-based Watershed Model with Spatial Hortonian Infiltration and Ruh-Off/On  

Technology Transfer Automated Retrieval System (TEKTRAN)

A physically based, distributed rainfall-runoff-runon model was developed for event-based studies of dynamic watershed processes, including space-time patterns of state variables (e.g., soil profile water storage) and fluxes (e.g., overland flow and infiltration). A routing hierarchy for dynamic ru...

385

Preprocessing: Geocoding of AVIRIS data using navigation, engineering, DEM, and radar tracking system data  

NASA Technical Reports Server (NTRS)

Remotely sensed data have geometric characteristics and representation which depend on the type of the acquisition system used. To correlate such data over large regions with other real world representation tools like conventional maps or Geographic Information System (GIS) for verification purposes, or for further treatment within different data sets, a coregistration has to be performed. In addition to the geometric characteristics of the sensor there are two other dominating factors which affect the geometry: the stability of the platform and the topography. There are two basic approaches for a geometric correction on a pixel-by-pixel basis: (1) A parametric approach using the location of the airplane and inertial navigation system data to simulate the observation geometry; and (2) a non-parametric approach using tie points or ground control points. It is well known that the non-parametric approach is not reliable enough for the unstable flight conditions of airborne systems, and is not satisfying in areas with significant topography, e.g. mountains and hills. The present work describes a parametric preprocessing procedure which corrects effects of flight line and attitude variation as well as topographic influences and is described in more detail by Meyer.

Meyer, Peter; Larson, Steven A.; Hansen, Earl G.; Itten, Klaus I.

1993-01-01

386

Dynamic simulations of geologic materials using combined FEM/DEM/SPH analysis  

SciTech Connect

An overview of the Lawrence Discrete Element Code (LDEC) is presented, and results from a study investigating the effect of explosive and impact loading on geologic materials using the Livermore Distinct Element Code (LDEC) are detailed. LDEC was initially developed to simulate tunnels and other structures in jointed rock masses using large numbers of polyhedral blocks. Many geophysical applications, such as projectile penetration into rock, concrete targets, and boulder fields, require a combination of continuum and discrete methods in order to predict the formation and interaction of the fragments produced. In an effort to model this class of problems, LDEC now includes implementations of Cosserat point theory and cohesive elements. This approach directly simulates the transition from continuum to discontinuum behavior, thereby allowing for dynamic fracture within a combined finite element/discrete element framework. In addition, there are many application involving geologic materials where fluid-structure interaction is important. To facilitate solution of this class of problems a Smooth Particle Hydrodynamics (SPH) capability has been incorporated into LDEC to simulate fully coupled systems involving geologic materials and a saturating fluid. We will present results from a study of a broad range of geomechanical problems that exercise the various components of LDEC in isolation and in tandem.

Morris, J P; Johnson, S M

2008-03-26

387

Open-source MFIX-DEM software for gas-solids flows: Part II — Validation studies  

Microsoft Academic Search

With rapid advancements in computer hardware and numerical algorithms, computational fluid dynamics (CFD) has been increasingly employed as a useful tool for investigating the complex hydrodynamics inherent in multiphase flows. An important step during the development of a CFD model and prior to its application is conducting careful and comprehensive verification and validation studies. Accordingly, efforts to verify and validate

Tingwen Li; Rahul Garg; Janine Galvin; Sreekanth Pannala

2012-01-01

388

Research Article Effects of lidar post-spacing and DEM resolution to mean slope  

E-print Network

CHOW*{ and MICHAEL E. HODGSON{ {Department of Earth and Resource Science, University of Michigan--Flint, Flint, MI 48502, USA {Department of Geography, University of South Carolina, Columbia, SC 29208, USA

Hodgson, Michael E.

389

Effects of LIDAR DEM resolution in hydrodynamic modelling: model sensitivity for cross-sections  

Microsoft Academic Search

With the development of science and technology the entire Earth, together with all of its phenomena, is gradually becoming an object of computer digitisation. For several years, this process has also affected water components, which are essential for the development of humans and economies on Earth. Therefore, monitoring of its resources and movement across the Earth's surface is the main

M. Podhorányi; J. Unucka; P. Bobál; V. ?íhová

2011-01-01

390

Modeling of glacier bed topography from glacier outlines, central branch lines, and a DEM  

Microsoft Academic Search

Due to the expected future climate change, glacier ice as a resource will be further diminished and its sea-level rise contribution further increased. A key for a more accurate determination of future glacier evolution is to improve our currently sparse knowledge on glacier bedrock topography. Here, we present a simplified method implemented in a geographic information system to approximate subglacial

Frank Paul; Andreas Linsbauer

2012-01-01

391

Aus dem Leben eines Beraters Als Mathematiker bei d-fine  

E-print Network

· Konzeption und Validierung von Modellen für die Bewertung und das Hedging von derivativen Produkten · Rating Scottish Widows IP Sparkasse KölnBonn Talanx Toyota Kreditbank UBS Union Investment VW Financial

Ferrari, Patrik L.

392

Comparison of mega-flood features of the Channeled Scabland and Martian outflow channels using DEMs  

NASA Astrophysics Data System (ADS)

Although current Martian surfaces are too cold and dry to hold liquid water, fluvial features such as valley networks and outflow channels have been observed on the surfaces. The analyses of the fluvial features on Mars are useful for examining past climatic conditions. Outflow channels are the characteristic large flood features on Mars and similar to some large terrestrial flood features such as those in the Channeled Scabland in east-central Washington, USA. The channeled scabland was formed by the Pleistocene Missoula Flood derived from the margins of the Cordilleran Ice Sheet, Glacial Lake Missoula. Thus the Channeled Scabland is useful for a comparison with Martian flood features and examining the paleoenvironment on Mars. However the effect of the Missoula Flood on the formation of the Channeled Scabland has some unresolved questions. Therefore, in this study we analyze the topography of the Channeled Scabland and the area of Glacial Lake Missoula using the ASTER Global Digital Elevation Model (ASTER GDEM) and The National Elevation Dataset (NED). We compare the topography of the Channeled Scabland with that of neighboring areas that has been free of megafloods., Topography in the area of Glacial Lake Missoula is also compared with neighboring areas without glacial lakes. We analyze the frequency distribution and statistical parameters of geomorphometric properties, e.g. slope angle, slope aspect, curvature, and drainage density of each region. We then compare the results with those for Martian outflow channels. The results show that average slope angle increases from the Channeled Scablands to non-megafloods areas, from areas without glacial lakes to the area of Glacial Lake Missoula, and from Martian flood areas to the Channeled Scabland. The same relation holds true for standard deviation except that the standard deviation of the Channeled Scabland is larger when compared to non-megafloods areas, reflecting the generally flat but locally steep topography of the former.

Okano, Miki; Oguchi, Takashi

2014-05-01

393

Simulations of Fracture and Fragmentation of Geologic Materials using Combined FEM/DEM Analysis  

SciTech Connect

Results are presented from a study investigating the effect of explosive and impact loading on geological media using the Livermore Distinct Element Code (LDEC). LDEC was initially developed to simulate tunnels and other structures in jointed rock masses with large numbers of intact polyhedral blocks. However, underground structures in jointed rock subjected to explosive loading can fail due to both rock motion along preexisting interfaces and fracture of the intact rock mass itself. Many geophysical applications, such as projectile penetration into rock, concrete targets, and boulder fields, require a combination of continuum and discrete methods in order to predict the formation and interaction of the fragments produced. In an effort to model these types of problems, we have implemented Cosserat point theory and cohesive element formulations into the current version of LDEC, thereby allowing for dynamic fracture and combined finite element/discrete element simulations. Results of a large-scale LLNL simulation of an explosive shock wave impacting an elaborate underground facility are also discussed. It is confirmed that persistent joints lead to an underestimation of the impact energy needed to fill the tunnel systems with rubble. Non-persistent joint patterns, which are typical of real geologies, inhibit shear within the surrounding rock mass and significantly increase the load required to collapse a tunnel.

Morris, J P; Rubin, M B; Block, G I; Bonner, M P

2005-05-26

394

Simulations of Fracture and Fragmentation of Geologic Materials using Combined FEM/DEM/SPH Analysis  

SciTech Connect

An overview of the Lawrence Discrete Element Code (LDEC) is presented, and results from a study investigating the effect of explosive and impact loading on geologic materials using the Livermore Distinct Element Code (LDEC) are detailed. LDEC was initially developed to simulate tunnels and other structures in jointed rock masses using large numbers of polyhedral blocks. Many geophysical applications, such as projectile penetration into rock, concrete targets, and boulder fields, require a combination of continuum and discrete methods in order to predict the formation and interaction of the fragments produced. In an effort to model this class of problems, LDEC now includes implementations of Cosserat point theory and cohesive elements. This approach directly simulates the transition from continuum to discontinuum behavior, thereby allowing for dynamic fracture within a combined finite element/discrete element framework. In addition, a Smooth Particle Hydrodynamics (SPH) capability has been incorporated into LDEC, permitting the simulation of fluid-structure interaction. We will present results from a study of detonation-induced fracture and fragmentation of geologic media surrounding a tunnel using LDEC.

Morris, J P; Johnson, S M

2007-04-05

395

Faculdade ou Institutos Total Dem/Ofer Faculdade de Direito -FDD 12  

E-print Network

Tecnologia em Arquitetura e Urbanismo 8 THA - Dep. de Teoria e História em Arquitetura e Urbanismo 7. Teorias e Fundamentos 9 FACE 45 ADM 21 CCA - Ciências Contábeis 5 Gestão de políticas Públicas - FACE 5 Instituto de Ciências Biológicas - IB 51 CEL - Biologia Celular 8 BOT - Botânica 10 CFS - Ciência

Maier, Rudolf Richard

396

Physician anger: Leggo dem managed care blues--leadership beyond the era of managed cost.  

PubMed

While managed care has caused great disruption, it has also provided physician executives with a natural leadership raison d'être. Managed care, with all its pros and cons, is largely a response to certain unrelenting trends. The core functions of leaders comprise the stewardship of organizations and colleagues in response to these trends. Four trends are explored: (1) The demise of open-ended funding of American health care; (2) continued competition for health care resources; (3) thriving pluralism; and (4) patients continually adjusting to assure themselves of appropriate health care access, quality, and service. In the 21st century, the industry will need a new brand of leader, one capable of balancing the needs of the professionals with the business and accountability requirements of a permanently competitive and resource-constrained service industry. The keys to successful leadership in the future include: (1) Clear service differentiation and a compelling vision to match it; (2) recruiting and retaining top clinical talent, including the required return to physician self-direction and governance; (3) successful partnerships with others outside your organization; and (4) a steady focus on performance in all its dimensions. PMID:10351726

Kirz, H L

1999-01-01

397

Zur roboterassistierten zementfreien Hüftprothesenimplantation mit dem System Caspar : eine prospektive Studie von 51 Fällen.  

E-print Network

??Problem: Um eine präzise Schaftimplantation zu erreichen, wurde der Operationsroboter CASPAR (Computer Assisted Surgical Planning And Robotics) eingesetzt. Die Fragestellung war: Ist der Einsatz des… (more)

Münst, Luise

2005-01-01

398

Automatic Building Extraction from DEMs using an Object Approach and Application to  

E-print Network

of Photogrammetry and Remote Sensing 63, 3 (2008) 365-381" DOI : 10.1016/j.isprsjprs.2007.09.003 #12;Model, 3D-reconstruction commu- nications, disaster recovery or creation of virtual realities require to be able to automatically build 3D-models with connected planar facets of towns. However the 3D building reconstruction

Paris-Sud XI, Université de

399

Die Ultrastruktur der Zellen aus dem interstitiellen Bindegewebe von Arion rufus (L.), Pulmonata, Gastropoda  

Microsoft Academic Search

The connective tissue of the membranes and the body wall ofArion rufus (L.) shows the following details:1.The vesicular cells (Blasenzellen) are characterized by numerous vesicles produced by the cell membrane. They appear in two different functional states: a) as cells, which contain a high amount of glycogen but only few membranes of the smooth-surfaced endoplasmic reticulum and b) as cells,

Günter Wondrak

1969-01-01

400

Wortbildung und Fremdsprachenunterricht. Ein Beitrag zur Vermittlung zwischen Theorie und Praxis [Word Formation and Foreign Language Teaching. A Contribution to Bridging between Theory and Practice (Part 2)].  

ERIC Educational Resources Information Center

Only regular word-building patterns are considered. Patterns are chosen for their communicative value, degree of difficulty, and applicability. Examples of word-building exercises are given, taken from actual texts. Work in word formation is recommended even for the beginners' level. (IFS/WGA)

Storch, Guenther

1979-01-01

401

Wortbildung und Fremdsprachenunterricht. Ein Beitrag zur Vermittlung zwischen Theorie und Praxis [Word Formation and Foreign Language Teaching. A Contribution to Bridging between Theory and Practice (Part 1)].  

ERIC Educational Resources Information Center

Sees word formation as an economical, important means of building vocabulary. Gives examples showing several different word-building patterns. Sees as a reasonable teaching goal the gaining of competence only in "receptive" word formation, i.e., recognition. The student can learn to build new words only from simple, frequently recurring patterns.…

Storch, Guenther

1979-01-01

402

"Astronomica" in the Correspondence between Leonhard Euler and Daniel Bernoull (German Title: "Astronomica" im Briefwechsel zwischen Leonhard Euler und Daniel Bernoulli)  

NASA Astrophysics Data System (ADS)

The Euler Commission of the Swiss Academy of Sciences intends to terminate the edition of Leonhard Euler's works in the next year 2011 after nearly one hundred years since the beginning of the editorial works. These works include, e.g., Volume 3 of the Series quarta A which will contain the correspondence between Leonhard Euler (1707-1783) and Daniel Bernoulli (1700-1783) and which is currently being edited by Dr. Emil A. Fellmann (Basel) and Prof. Dr. Gleb K. Mikhailov (Moscow). This correspondence contains more than hundred letters, principally from Daniel Bernoulli to Euler. Parts of this correspondence were published uncommented already in 1843. It is astonishing that, apart from mathematics and physics (mainly mechanics and hydrodynamics), many topics addressed concern astronomy. The major part of the preserved correspondence between Euler and Daniel Bernoulli, in which astronomical themes are discussed, concerns celestial mechanics as the dominant discipline of theoretical astronomy of the eighteenth century. It was triggered and coined mainly by the prize questions of the Paris Academy of Science. In more than two thirds of the letters current problems and questions concerning celestial mechanics of that time are treated, focusing on the lunar theory and the great inequality in the motions of Jupiter and Saturn as special applications of the three body problem. In the remaining letters, problems concerning spherical astronomy are solved and attempts are made to explain certain phenomena in the field of "cosmic physics" concerning astronomical observations.

Verdun, Andreas

2010-12-01

403

Zwischen Wollen, aber nicht können und Können, aber nicht wollen: Übergangsprobleme von Jugendlichen in Japan am Beispiel der „Freeter`` und „NEETs``  

NASA Astrophysics Data System (ADS)

Caught between wanting but not being able to, and being able, but not wanting to: Transitional problems among Japanese youths based on the examples of "Freeters" and "NEETs" - The study of processes of transition from the education system to employment is particularly important in light of youth unemployment. In Japan this transition process is often declared to be successful. In recent years, however, numerous signs have indicated a change in the situation. This article analyses this problem based on the examples of two Japanese social groups, "Freeters" and "NEETs". These terms refer to young adults who do not immediately move into to regular employment. The article begins by analysing the causes, then comments on education policy measures undertaken to tackle the issue. Drawing on scientifically grounded models it is shown that both social groups are characterised by meagre formal school qualifications. Social background, by contrast, is not particularly relevant; although there are hints that parents' financial means play an increasingly important role in determining whether a young person attends a high-level educational institution. Although public opinion in Japan frequently attributes values and attitudes to these groups that deviate from the norm, this is not conclusively supported by existing empirical findings. Consequently, the reasons for these transitional problems tend to be perceived as being connected to the difficult labour market situation resulting from the ongoing economic crisis. In addition to certain education policy initiatives, Japan will therefore rely heavily in future on the ability to effectively manage the integration of its shrinking cohorts of school and university graduates.

Eswein, Mikiko; Pilz, Matthias

2012-08-01

404

Tourette Syndrom.  

E-print Network

??Infektionen und postinflammatorische Prozesse scheinen bei einer Untergruppe von Tourette-Patienten ein wichtiger pathogenetischer Faktor zu sein. Einige Studien berichten von Streptokokken- und Mykoplasmeninfektionen im Zusammenhang… (more)

Nuernberger, Judith

2008-01-01

405

Organic chemistry as a useful tool in structural biology.  

E-print Network

??Die vorliegende Dissertation beschreibt fünf miteinander in direktem Zusammenhang stehende Projekte. Das Ziel dieser Arbeit war sowohl die Synthese von fluorierten Kohlenhydraten als auch die… (more)

Fischer, Michael

2011-01-01

406

Die Bedeutung der Rumänischen Revolution für den Legitimationsdiskurs der Postkommunisten in den Transformationsjahren 1990-1994.  

E-print Network

??Revolution oder Staatsstreich? Eine der meist gestellten Fragen im Zusammenhang mit der Rumänischen Revolution, die sowohl die wissenschaftliche Auseinandersetzung als auch die gesellschaftliche und politische… (more)

Hutter, Roman

2013-01-01

407

Die Rezeption Yoshimoto Bananas in Printmedien des deutschsprachigen Raums.  

E-print Network

??In dieser Arbeit werden Zeitungs- und Zeitschriftenartikel, die sich mit der japanischen Autorin Yoshimoto Banana befassen, untersucht und in Zusammenhang gestellt mit literaturtheoretischen Rezeptionstheorien des… (more)

Büchel, Barbara Anita

2009-01-01

408

Astronomische Kupferstiche von Gottfried Teuber für Erhard Weigel  

NASA Astrophysics Data System (ADS)

Zum Spektrum nichtverbaler Zeugnisse aus der Geschichte der Wissenschaften zählen auch die zahlreichen bildhaften Dokumente, auf denen die Objekte der wissenschaftlichen Untersuchung festgehalten sind, darunter auch die Kupferstiche (später Fotografien), die den astronomischen Büchern und Schriften beigegeben worden sind. Welcher wissenschaftshistorisch relevante Informationsgehalt ist nun solchen nichtverbalen Zeugnissen neben dem künstlerischen Aspekt der Illustration des Textes zuzubilligen? In Form einer Fallstudie soll im Vortrag ein bisher wenig beachteter Aspekt einer Antwort auf diese Frage angerissen werden. Im Rahmen dieser Fallstudie werden einige Kupferstiche aus dem Himmels=Zeiger`` von Erhard W eigel (1625-1699) vorgestellt, seit 1653 Professor für Mathematik an der Universität Jena und maßgeblicher Initiator der Kalenderreform in den protestantischen Ländern von 1699. Die in diesen Stichen enthaltenen Informationen können grob in drei Gruppen eingeteilt werden: A Aussagen zur Astronomie (dargestellte Himmelserscheinung), B Aussagen zur Drucktechnik (und künstlerischen Gestaltung), C Aussagen zur Biographie (des Herstellers bzw. Auftraggebers). Meines Erachtens ist der Aspekt C in der Historiographie bisher nicht erkannt worden. Hierauf soll mit einem Beispiel aufmerksam gemacht werden, wobei es um die Biographien von zwei Personen geht: die des Buchautors (Weigel) und die des Herstellers des Kupferstiches (Gottfried Teuber). Die Auswertung des Beispiels zeigt, daß durch Beachtung der sonst unauffällig erscheinenden Hersteller eines Kupferstiches Ansatzpunkte gefunden werden können, um Material für die noch unzureichend erforschte Beziehung zwischen den Gelehrten aus der ersten Reihe und deren Gehilfen aufzuspüren.

Herbst, Klaus-Dieter

409

An extended DEM–CFD model for char combustion in a bubbling fluidized bed combustor of inert sand  

Microsoft Academic Search

This paper proposes a transient three-phase numerical model for the simulation of multiphase flow, heat and mass transfer and combustion in a bubbling fluidized bed of inert sand. The gas phase is treated as a continuum and solved using the computational fluid dynamics (CFD) approach; the solid particles are treated as two discrete phases with different reactivity characteristics and solved

Yongming Geng; Defu Che

2011-01-01

410

Extraction of morphotectonic features from DEMs: Development and applications for study areas in Hungary and NW Greece  

Microsoft Academic Search

A procedure for the consistent application of digital terrain analysis methods to identify tectonic phenomena from geomorphology is developed and presented through two case studies. Based on the study of landforms related to faults, geomorphological characteristics are translated into mathematical and numerical algorithms. Topographic features represented by digital elevation models of the test areas were extracted, described and interpreted in

G. Jordan; B. M. L. Meijninger; D. J. J. van Hinsbergen; J. E. Meulenkamp; P. M. van Dijk

2005-01-01

411

ERS tandem InSAR processing for DEM generation, glacier motion estimation and coherence analysis on Svalbard  

Microsoft Academic Search

This paper describes the unique InSAR (Interferometric Synthetic Aperture Radar) processing algorithms at Norwegian Defence Research Establishment (FFI) and how ERS (European Remote Sensing Satellite) tandem data are used to prove the high performance of the processing chain. The InSAR baselines are estimated from the high precision orbit data only, without using ground control points in the Svalbard test area.

K. Eldhuset; P. H. Andersen; S. Hauge; E. Isaksson; D. J. Weydahl

2003-01-01

412

Phonetische Korrektur mit dem Frequenzfiltergeraet SUVAG-Lingua (Phonetic Correction with the Frequency Filter Device SUVAG-Lingua)  

ERIC Educational Resources Information Center

Maintains that teaching phonetics should be aimed at enabling the learner to correct himself and that intonation, rhythm and suprasegmental phonemes have commonly been neglected. Describes the value and use of the SUVAG-Lingua Frequency Filter for correcting pronunciation, individually and in groups. (Text is in German.) (IFS/WGA)

Kettemann, Bernhard

1977-01-01

413

Die Bewertung von Textaufgaben - dargestellt an Beispielen aus dem Franzoesischunterricht (Grading Textbook Lessons -- Presented with Examples from Teaching French)  

ERIC Educational Resources Information Center

Explains and illustrates the term "textbook lesson," and mentions the considerations that have led to the recommended grading system. The chief aim is to achieve uniformity in grading. Offers recommendations for formulating and ordering lessons, grading criteria, awarding of points and key for computing points. (Text is in German.) (IFS/WGA)

Edener, Wilfried

1975-01-01

414

Uberlegungen zur Arbeit mit Strukturubungen nach dem "Tandemprinzip" (Reflections of Work with Structured Exercises Based on the "Tandem Principle")  

ERIC Educational Resources Information Center

The tandem principle grows from the belief that foreign languages can be mutually supportive and informative if taught together. The pairing of French and German students for pattern practice in each other's native language is a practical application of the principle. (RS)

Leupold, Eynar

1972-01-01

415

(as) Stammzellen aus dem Knochenmark knnen nach einem Infarkt die Auswurf-Leistung des Herzens verbessern dies  

E-print Network

Studie »Reconstruction of the canine achilles tendon defect using an in vitro tissue engineered long tendon construct«. Die Deutsche Diabetes-Gesellschaft, Bochum, bewilligte ... Dr. med. Elmar Jaeckel

Manstein, Dietmar J.

416

Die konkrete Situation als Ausgangspunkt für die Begegnung mit dem "Du" bei Franz Fischer und Carl R. Rogers.  

E-print Network

??Täglich werden Menschen mit Situationen konfrontiert, die konkret und unmittelbar erlebt werden. In dieser Begegnung spürt der Mensch eine Verwobenheit von emotionalen, geistigen und körperlichen… (more)

Semler, Renate

2013-01-01

417

Suche nach der Produktion einzelner Top-Quarks durch Flavor-ändernde neutrale Ströme mit dem CDF II Experiment.  

E-print Network

??Verschiedene phaenomenologische Erweiterungen des Standard Modells sagen die Produktion von Einzel-Top-Quarks mittels Flavor-aendernden Neutralen Stroemen (FCNC) in fuehrender Ordnung vorher. Ein Beispiel fuer einen solchen… (more)

Papaikonomou, Antonios

2009-01-01

418

reinfarction, there was a statistically significant benefit dem-onstrated for enoxaparin vs unfractionated heparin in the  

E-print Network

unfractionated heparin in the full-dose tenecteplase group (4.4% vs 15.9%, log-rank P=.003) that was attenuated unfractionated heparin, as well as the unequal and nonrandom use of these agents in these 3 trials, confound treatment of STEMI with full- dose fibrinolytic drugs and unfractionated heparin, the use of half

Huey, Raymond B.

419

Comparison of DEM and BEET linearization techniques for flash analog-to-digital converters using a SFDR metric  

Microsoft Academic Search

Data converter linearization has been a subject of some interest for most of the past decade. New methods of linearizing analog-to-digital converters (ADC) continue to be developed. Various linearization methods are available but their comparative strengths and weaknesses are not easily recognizable, making it somewhat difficult to determine which compensator would provide maximum benefit for a specific device. This paper

Christopher D. McGuinness; Eric J Balster; Frank A. Scarpino

2010-01-01

420

3D morphometry of valley networks on Mars from HRSC/MEX DEMs: Implications for climatic evolution through time  

NASA Astrophysics Data System (ADS)

valley networks have been identified mainly in the Noachian heavily cratered uplands. Eight dense branching valley networks were studied in Noachian terrains of Huygens, Newcomb and Kepler craters, south Tyrrhena Terra, and Thaumasia, in Hesperian terrains of Echus Plateau and west Eberswalde craters, and in Amazonian terrains of Alba Patera, using images and digital elevation models from the Mars Express High Resolution Stereo Camera to determine 2D and 3D morphometric parameters. Extracted geomorphic parameters show similar geometry to terrestrial valleys: drainage densities, organization from bifurcation ratios and lengths ratios, Hack exponent consistent with terrestrial values of ~0.6, and progressive deepening of valleys with increasing Strahler order. In addition, statistics on valley depths indicate a deeper incision of Noachian valleys compared to younger post-Noachian valleys (<25 m for Amazonian ones compared to >100 m for Noachian ones), showing a strong difference in fluvial erosion. These characteristics show that dense Martian valley networks formed by overland flows in relation to a global atmospheric water cycle in Noachian epoch and confirm that the later stages of activity may be related to shorter duration of activity, distinct climatic conditions, and/or regional processes, or conditions.

Ansan, V.; Mangold, N.

2013-09-01

421

Evaluation of ASTER and SRTM DEM data for lahar modeling: A case study on lahars from Popocatpetl Volcano, Mexico  

E-print Network

on Popocatépetl Volcano, Mexico. Two GIS-based models are used for lahar modeling, LAHARZ and a flow of the glaciers on top of the volcano and data on recent and historical lahar events. As regards recently observed

Kääb, Andreas

422

Application of high resolution DEM data to detect rock damage from geomorphic signals along the central San Jacinto Fault  

Microsoft Academic Search

We analyze geomorphic properties extracted from LiDAR and SRTM (Shuttle Radar Topography Mission) data to test whether the damage zone along the central San Jacinto Fault (SJF) zone can be resolved with remotely-sensed data in a quantitative fashion. The SJF is one of the most active faults in southern California, with well expressed geomorphology and a fast slip rate, as

Neta Wechsler; Thomas K. Rockwell; Yehuda Ben-Zion

2009-01-01

423

Analysing, quantifying and modelling soil erosion on steep hillslopes in different climatic areas using LiDAR and SFM DEMs  

NASA Astrophysics Data System (ADS)

Soil erosion is a worldwide well known problem and has therefore been subject to various scientific studies, especially on agricultural areas. However soil erosion on steep hillslopes in mountainous drainage basins can be a threat to human infrastructure as it supplies material, e.g. for debris flows to torrents. The study presented here aims to analyse, quantify and model soil erosion on (very) steep hillslopes free of vegetation in different climatic areas ranging from South Germany to Central Italy. Multitemporal digital elevation models were acquired with terrestrial laserscanning and from terrestrial and aerial structure from motion-based imagery. Analysis of erosion is mainly based on slope wash and rill erosion during summer months as well as erosion through freezing and melting processes during winter months in catchments of the Bavarian Alps. Erosional processes in the Mediterranean are mainly controlled by different precipitation regimes throughout the year. Annual erosion and accumulation rates are quantified and used for modelling purposes. First results of the presented project show, that the amount of material eroded is mainly controlled by the size of the sediment contributing area. However there are also other controlling factors, such as slope angle, slope length and vegetation cover which are investigated within this project.

Neugirg, Fabian; Haas, Florian; Kaiser, Andreas; Schmidt, Jürgen; Becht, Michael

2014-05-01

424

A comparison of rigorous sensor model and rational function model for DEM generation from stereo SPOT images  

Microsoft Academic Search

Generation of accurate digital elevation models from stereo satellite images are becoming increasingly of interest. The primary\\u000a focus of this paper is to compare rigorous sensor model (RSM) and rational function model (RFM) for accurate generation of\\u000a digital elevation model from stereo satellite images. In the application of RSM, first degree of polynomials for the modeling\\u000a the satellite position ?

Ki Won Ahn; Byung Uk Park; Gun Gi Lee; Doo Chun Seo

2002-01-01

425

Perkutane Katheter-basierte Behandlung der schweren Mitralinsuffizienz Erste Schweizer Erfahrungen mit dem MitraClip ® System  

Microsoft Academic Search

Summary Many patients with severe mitral regurgitation and a high operative risk are treated conservatively despite their high morbidity and mortality. Here we report the first Swiss experience of a new technique for transve- nous mitral valve reconstruction using the Mitraclip ® system and performed in high-risk patients. Methods: Retrospective analysis of the clinical, echocardiographic and periprocedural data of the

Giovanni Pedrazzinia; Daniel Sürdera; Marco Moccettib; David Hürlimannb; Franco Faletraa; Christian Felixb; Dominique Bettex; Elena Pasotti; Ines Bühler; Julija Klimusina; Thomas F. Lüscher; Tiziano Moccetti; Jürg Grünenfelderb; Roberto Cortib

2010-01-01

426

1 die abteilung revision der Generalverwaltung der Max-Planck-Gesellschaft hat die Jahresrechnung 2012 entsprechend dem ihr von der  

E-print Network

aNHaNg 1 die abteilung revision der Generalverwaltung der Max-Planck- Gesellschaft hat die Wirtschaftsprüfungsgesellschaft, München, hat den Jahresabschluss des Max-Planck-Instituts für Plasmaphysik (haushalt B) und die Privaten Ver- mögens der Max-Planck-Gesellschaft ­ entsprechend den von der haupt- versammlung der

Falge, Eva

427

DEM-optical-radar data integration for palaeohydrological mapping in the northern Darfur, Sudan: implication for groundwater exploration  

Microsoft Academic Search

North?western Sudan, as a part of the eastern Sahara, is among the driest places on earth. However, the region underwent drastic climatic changes through the alternation of dry and wet conditions in the past. During humid phases, when the rain was plentiful over a prolonged time period, the surface was veined by rivers and dotted by large lakes. The new

E. Ghoneim; F. El-Baz

2007-01-01

428

Die Feder mit dem Degen tauschen – oder umgekehrt? Zur Dialektik der neueren transnationalen Kommunikation al-Qaidas  

Microsoft Academic Search

Zusammenfassung  Der vorliegende Aufsatz analysiert die sich verändernden Formen islamistischer Kommunikation am Beispiel der neueren Botschaften\\u000a al-Qaidas. In Abgrenzung zu der über Jahrzehnte zu beobachtenden kategorisch anti-demokratischen Rhetorik islamistischer Gruppierungen\\u000a kennzeichnen sich die transnationalen Ausführungen der Führungsspitze al-Qaidas in den letzten Jahren verstärkt durch eine\\u000a inhaltsorientierte Auseinandersetzung mit demokratischen Funktionsweisen. Basierend auf einer theoriegeleiteten Darstellung\\u000a islamistischer Grundprinzipien intendiert der vorliegende Aufsatz

Christoph Schuck

2009-01-01

429

854 Inorganic Chemistry, Vol. Id, No. 4, 1977 with the known spectra'.2of other NF4+salts clearly dem-  

E-print Network

bands in (NF4)$nF6 are also straightforward. The vibrational spectra of octahedral SnF6'- are ~ell-known'~~'~-'~and establish the presence of SnF62-in (NFJ2SnF6 (see Table 11). The anion spectrum in NF4SnF5shows a pattern tentative as- signments for the stretching modes of SnF5-and GeFS-based on tetrameric anions, which

Goodman, Wayne

430

Hohere Analysis und elementare Differentialgeometrie, WS 12/13, 2. Ubungsblatt  

E-print Network

die L¨ange des Parabelbogens y = x2 zwischen den Punk- ten (-1, 1) und (2, 4) und vergleiche zur Abstandes zwischen den beiden Punk- ten ist. Man zeige, dass dieses Kraftfeld konservativ ist, indem man ein

Schmeiser, Christian

431

The master and the telescopes - the interplay between astronomy and optics in history (German Title: Der Meister und die Fernrohre - Das Wechselspiel zwischen Astronomie und Optik in der Geschichte)  

Microsoft Academic Search

The use of the telescope for astronomical observations since 1609 was one of the milestones in the celestial research. The contributions in this volume present new insights into the invention of the telescope and its relations to reading stones and spectacles, present investigations of special telescope types of early manufacturers, and analyze the telescopes of some historical observatories and the

Jürgen Hamel; Inge Keil

2007-01-01

432

H.C. Schumacher - Center of international communication in astronomy and mediator betwen Denmark an Germany. (German Title: H.C. Schumacher - Zentrum der internationalen Kommunikation in der Astronomie und Mittler zwischen Dänemark und Deutschland)  

NASA Astrophysics Data System (ADS)

As the editor of the ``Astronomische Nachrichten'', H.C. Schumacher played an outstanding role among the astronomers of the first half of the 19th century. Altona, his place of activity, belonged to the kingdom of Denmark. Both the foundation of the ``Astronomische Nachrichten'' and its existence depended for several decades on the support by the Danish kings and high-ranking officials at the Copenhagen court. This paper analyses these questions on the basis of previously unused archival sources and discusses also Schumacher's life and his relations to the royal dynasty.

Hamel, Jürgen

433

The controversy between Alexander Friedmann and Albert Einstein about the possibility of a non-static world (German Title: Die Kontroverse zwischen Alexander Friedmann und Albert Einstein um die Möglichkeit einer nichtstatischen Welt)  

Microsoft Academic Search

Einstein's treatment of the cosmological problem as well as his unshakeable adherence to his own static solution of the complete field equations was throughout determined by Ernst Mach's idea of relativity of inertia. Friedmann, however, like Eddington, Weyl and others did not consider Mach's principle to be a part of general relativity, and so he regarded a time dependent developing

Georg Singer

2005-01-01

434

Der Briefwechsel zwischen Sidonie Na?dherny? und Albert Bloch : September 1947-September 1950 : mit einer Einfu?hrung in die Widmungsgedichte von Karl Kraus an Sidonie Na?dherny?  

E-print Network

Die Aufgabe dieser Arbeit besteht darin, Sidonie Na?dherny? Einfluß auf das Werk von Karl Kraus, vor allem auf seine Lyrik, an Hand der Albert Bloch/Sidonie Na?dherny?-Korrespondenz auszuwerten. Neben den eigentlichen ...

Champion, Elke Lorenz

1998-01-01

435

Hardware-Abbildung eines videobasierten Verfahrens zur echtzeitfähigen Auswertung von Winkelhistogrammen auf eine modulare Coprozessor-Architektur  

NASA Astrophysics Data System (ADS)

Dieser Beitrag behandelt die Abbildung eines videobasierten Verfahrens zur echtzeitfähigen Auswertung von Winkelhistogrammen auf eine modulare Coprozessor-Architektur. Die Architektur besteht aus mehreren dedizierten Recheneinheiten zur parallelen Verarbeitung rechenintensiver Bildverarbeitungsverfahren und ist mit einem RISC-Prozessor verbunden. Eine konfigurierbare Architekturerweiterung um eine Recheneinheit zur Auswertung von Winkelhistogrammen von Objekten ermöglicht in Verbindung mit dem RISC eine echtzeitfähige Klassifikation. Je nach Konfiguration sind für die Architekturerweiterung auf einem Xilinx Virtex-5-FPGA zwischen 3300 und 12 000 Lookup-Tables erforderlich. Bei einer Taktfrequenz von 100 MHz können unabhängig von der Bildauflösung pro Einzelbild in einem 25-Hz-Videodatenstrom bis zu 100 Objekte der Größe 256×256 Pixel analysiert werden. This paper presents the mapping of a video-based approach for real-time evaluation of angular histograms on a modular coprocessor architecture. The architecture comprises several dedicated processing elements for parallel processing of computation-intensive image processing tasks and is coupled with a RISC processor. A configurable architecture extension, especially a processing element for evaluating angular histograms of objects in conjunction with a RISC processor, provides a real-time classification. Depending on the configuration of the architecture extension, 3 300 to 12 000 look-up tables are required for a Xilinx Virtex-5 FPGA implementation. Running at a clock frequency of 100 MHz and independently of the image resolution per frame, 100 objects of size 256×256 pixels are analyzed in a 25 Hz video stream by the architecture.

Flatt, H.; Tarnowsky, A.; Blume, H.; Pirsch, P.

2010-10-01

436

Conditional logistic regression and odds ratio multifactor dimensionality reduction for the analysis of interactions of environmental risk factors and the 5-HT2A  – 1438 G/A polymorphism in anorexia nervosa.  

E-print Network

??Es ist bekannt, dass das Serotonin-System mit Essverhalten und Essstörungen in Zusammenhang steht. Im Zuge jüngerer genetischer Forschung wurden mehrere sogenannte Polymorphismen im Serotonin-System identifiziert.… (more)

Nader, Ingo

2008-01-01

437

Landslide-dammed lakes detection via ALOS\\/PALSAR InSAR DEM: A case study of the Iwate-Miyagi Nairiku earthquake  

Microsoft Academic Search

On 14th June 2008, the Japan Meteorological Agency recorded a 7.2 magnitude (Richter scale) earthquake with an epicenter depth of 8 km in the southern Iwate prefecture of the Tohoku region of Japan. In the hardest hit prefectures of Iwate and Miyagi, the earthquake produced 15 new landslide-dammed lakes; a phenomenon common when the earthquake hypocenter is within inland areas.

Tomohito Asaka; Yoshiyuki Yamamoto; Keishi Iwashita; Katsuteru Kudou; Hisao Fujii; Hajime Nishikawa

2010-01-01

438

Mass-balance estimates for Haut Glacier d'Arolla, Switzerland, from 2000 to 2006 using DEMs and distributed mass-balance modeling  

Microsoft Academic Search

A distributed mass-balance modeling approach is required to assess the impact of future climate scenarios on water availability in glaciated basins. Accurate estimation of water stored within the snow, firn and ice of such basins requires knowledge of the distributed snow and ice mass balance throughout the year. In this study, we estimate the annual mass balance and runoff for

Ruzica Dadic; Javier G. Corripio; Paolo Burlando

2008-01-01

439

PERSPECTIVES AND FEASIBILITY OF DERIVING MASS BALANCE OF MID LATITUDE MOUNTAIN GLACIERS FROM DIRECT GLACIOLOGIOCAL MEASUREMENTS, REPEATED OPTICAL IMAGERY AND DEMS  

Microsoft Academic Search

The melt of mountain glaciers provides the second major contribution to today's sea level rise. Direct measurements are restricted to a small percentage of glaciers and the distribution of these measurements is biased towards developed regions. Therefore, the important task of calculating the actual and future contribution of mountain glaciers to sea level rise must be based on remote sensing

A. Fischer

2009-01-01

440

Ausbildung in der Arbeit mit dem Sprachlabor fuer Lehramtskandidaten der Anglistik. Ein Erfahrungsbericht (Training in Language Laboratory Work for English Teacher Candidates. A Report on an Experience)  

ERIC Educational Resources Information Center

Reports on work at the University of Erlangen beginners' seminar on language laboratory work. This led to production of original laboratory exercises, which were tried out in a Gymnasium class. The aim was to introduce teacher candidates early to problems attending the introduction of language laboratories. (Text is in German.) (IFS/WGA)

Gorbahn, Adeline; Wilpert, Klaus

1975-01-01

441

Utopie: Eine Geschichte aus dem 15. Jahrhundert fur die Siebte Klasse, mit Ubungen (Utopia: A View of the 15th Century for the Seventh Class, with Exercises).  

ERIC Educational Resources Information Center

This German language textbook is intended for classroom use. The theme of the text relates to the Renaissance, and the narrative is based on Sir Thomas More's "Utopia" (1516) and relates to the experiences of its central character Raphael among the inhabitants of the strange island. Each chapter touches lightly on some thought provoking issue,…

Stott, Michael

442

MAPPING RELATIVE INUNDATION VULNERABILITY OF LAND PARCELS ON LOW-LYING GROUND: EXEMPLIFICATION WITH A PHOTOGRAMMETRICALLY-DERIVED DEM-BASED MODEL OF LAKES ENTRANCE, VICTORIA, AUSTRALIA  

Microsoft Academic Search

Using the townscape of Lakes Entrance (Victoria, Australia) as a case study, it is shown how, via adoption of a suitable digital spatial data handling process path, a high- resolution bare earth terrain model suitable for flood and storm surge\\/storm tide inundation modelling of low-lying coastal townscapes can be derived photogrammetrically. Model applications refer mostly to urban area planning and

P. J. Wheeler; J. Kunapo; J. A. Peterson; M. McMahon

443

Ein Märchen aus Tausend und einer Nacht? Kommentar zu dem Artikel von Frederike Wuermeling „Passt die Türkei zur EU und die EU zu Europa?“  

Microsoft Academic Search

\\u000a Zusammenfassung\\u000a   In ihrem in Heft 2\\/2007 dieser Zeitschrift erschienenen Artikel argumentiert Frederike Wuermeling, dass die vergleichsweise\\u000a niedrige Zustimmung der Türken zu den EU-Prinzipien kausal auf das niedrige Bruttosozialprodukt und den hohen Muslimanteil\\u000a zurückzuführen ist. Tatsächlich weist Wuermelings Analyse jedoch eine Vielzahl von methodischen und theoretischen Defiziten\\u000a auf. Die Kernaussagen ihres Beitrages sind deshalb durch die Daten nicht gedeckt.

Kai Arzheimer

2008-01-01

444

A geobotanical approach to the tropical rain forest environment of the Carajás Mineral Province (Amazon Region, Brazil), based on digital TM-Landsat and DEM data  

Microsoft Academic Search

Digital TM Landsat images integrated with elevation model variables were used to evaluate the potentiality of geobotany for lithological unit discrimination in the tropical rain forest environment of the Carajas Mineral Province, Brazilian Amazon region. The data set was analysed through digital image processing techniques (enhancements and non-supervised classification). The investigation has shown that the Up-Land rain forest vegetation in

W. R. PARADELLA; M. F. F. DA SILVA; N. DE A. ROSA

1994-01-01

445

This research is conducted to gauge the efficiency of the discrete element method (DEM) to reproduce the behaviour of masonry walls submitted to in plane or  

E-print Network

) to reproduce the behaviour of masonry walls submitted to in plane or membrane loading, and out of plane and the failure mode. Keywords: discrete element method, masonry walls, membrane loading, bending loading. 1 Introduction Several research have been conducted to simulate the behaviour of masonry structures, some

Paris-Sud XI, Université de

446

How to obtain constitutive relations about stress and density from DEM simulations Multi Scale Mechanics (MSM), University of Twente, Enschede, The Netherlands  

E-print Network

material properties involving, friction, rolling-resistance, and contact-adhesion. From a single simulation contact forces are equally important [1]. Friction, rolling-resistance, and contact-adhesion are active simulations to a later study. In the following, normal interactions, like adhesion and elasto-plastic contact

Luding, Stefan

447

Die Titicaca-See-Region auf dem Altiplano von Peru und Bolivien und die Folgen eingeführter Fische für Wildarten und ihren Lebensraum  

NASA Astrophysics Data System (ADS)

In the course of a long-term case study (since 1960) the interaction between different exotic fish (salmonids, atherinids) on the endemic ichthyofauna (genus Orestias: Cyprinodontidae) introduced to the interandean basin of Lake Titicaca was observed. The contribution deals not only with the actual consequences which endanger endemic species but also the socio-economic effects on the native Indian population, both causing further ecological problems in the region of concern.

Villwock, Wolfgang

1993-01-01

448

Valley Constraint Channel gradient was determined from 10m DEMs generated by interpolation between contour lines from USGS 7.5-minute  

E-print Network

with landslide inventories from the Siuslaw National Forest and the Oregon Depart- ment of Forestry. Management for western Oregon (Lorensen et al. 1994). The presumed species-specific relationships between habi- tat value-size streams (Sandercock 1991; Umpqua Land Exchange Project (ULEP 2001)) and that juvenile steelhead gener

449

Investigating a damaging buried sinkhole cluster in an urban area (Zaragoza city, NE Spain) integrating multiple techniques: Geomorphological surveys, DInSAR, DEMs, GPR, ERT, and trenching  

NASA Astrophysics Data System (ADS)

This contribution analyses a complex sinkhole cluster buried by urban elements in the mantled evaporite karst of Zaragoza city, NE Spain, where active subsidence has caused significant economic losses (~ 0.3 million Euro). The investigation, conducted after the development of the area, has involved the application of multiple surface and subsurface techniques. A detailed map of modern surface deformation indicates two active coalescing sinkholes, whereas the interpretation of old aerial photographs reveals the presence of two additional dormant sinkholes beneath human structures that might reactivate in the near future. DInSAR (Differential Interferometry Synthetic Aperture Radar) displacement data have limited spatial coverage mainly due to high subsidence rates and surface changes (re-pavement), and the Electrical Resistivity Tomography (ERT) and trenching investigations were severely restricted by the presence of urban elements. Nonetheless, the three techniques consistently indicate that the area affected by subsidence is larger than that defined by surface deformation features. The performance of the Ground Penetrating Radar (GPR) technique was adversely affected by the presence of highly conductive and massive anthropogenic deposits, but some profiles reveal that subsidence in the central sector of one of the sinkholes is mainly accommodated by sagging. The stratigraphic and structural relationships observed in a trench dug across the topographic margin of one of the sinkholes may be alternatively interpreted by three collapse events of around 0.6 m that occurred after 290 yr BP, or by progressive fault displacement combined with episodic anthropogenic excavation and fill. Average subsidence rates of > 6.6 mm/yr and 40 mm/yr have been calculated using stratigraphic markers dated by the radiocarbon method and historical information, respectively. This case study illustrates the need of conducting thorough investigations in sinkhole areas during the pre-planning stage including a geomorphic approach. A sound geomorphic model is essential for the proper design of the site investigation, the interpretation of the data and application of effective mitigation measures. Once sinkhole areas are developed, urban elements largely restrict the applicability and performance of multiple techniques, substantially decreasing the feasibility and benefit/effort ratio of the investigations.

Carbonel, Domingo; Rodríguez-Tribaldos, Verónica; Gutiérrez, Francisco; Galve, Jorge Pedro; Guerrero, Jesús; Zarroca, Mario; Roqué, Carles; Linares, Rogelio; McCalpin, James P.; Acosta, Enrique

2015-01-01

450

Factors that control the development of fault-bend versus fault-propagation folds: Insights from mechanical models based on the discrete element method (DEM)  

NASA Astrophysics Data System (ADS)

We investigate the role and relative importance of a range of geometric and mechanical factors in the development of contractional fault-related folds, with an emphasis on defining the factors that promote the development of fault-bend and fault-propagation folds. We construct a series of discrete-element mechanical models in order to test the effects of fault dip, bulk material strength, mechanical layer anisotropy and spacing, sedimentation rate, and boundary conditions on the style of fault-related fold that develops. We find that fault-bend folding is most favored at low fault ramp dips, with thinly-spaced mechanical layers, and strong layer strength contrasts. In contrast, conditions that inhibit slip on a potential upper detachment surface, such as increased friction and a fixed foreland boundary, encourage the development of fault-propagation folds. Additionally, steeper fault dips, more widely-spaced mechanical layers, and decreased layer strength contrast favor the increased localization of shear during the growth of structures. This leads to structures that deform by a mixture of fault-bend and fault-propagation folding styles. Observations of the distortional strains that develop in the model provide insight into the relationship between the different deformation mechanisms, such as flexural slip and localized shear, which accommodate structural growth and ultimately determine fault-related folding style. Thus, these models provide a context for understanding how rock and fault properties influence whether structures evolve as fault-bend or fault-propagation folds, or as combinations of these end members. We apply these insights to interpret two natural examples from the offshore Niger Delta outer fold-and-thrust belt that exhibit changes in structural style through time as a result of changes in fault properties and syntectonic sedimentation.

Hughes, Am