Application of micro-computed X-ray tomography for improving the hole erosion test analysis on high plastic clay     

Zaid  Bahaeldeen  Vollert  Florian  Gibmeier  Jens  Mengel  Lena  Stelzer  Oliver  Schneider  Achim 《Acta Geotechnica》2023,18(2):865-876

Acta Geotechnica - The hole erosion test (HET) was developed to simulate piping erosion and to study the erosion parameters of cohesive soils. The erosion rate in the HET is evaluated by the...  相似文献   

Potential of radiotelescopes for atmospheric line observations: I. Observation principles and transmission curves for selected sites     

Nicola Schneider  Joachim Urban 《Planetary and Space Science》2009,57(12):1419-1433

Existing and planned radiotelescopes working in the millimetre (mm) and sub-millimetre wavelengths range provide the possibility to be used for atmospheric line observations. To scrutinize this potential, we outline the differences and similarities in technical equipment and observing techniques between ground-based aeronomy mm-wave radiometers and radiotelescopes. Comprehensive tables summarizing the technical characteristics of existing and future (sub)-mm radiotelescopes are given. The advantages and disadvantages using radiotelescopes for atmospheric line observations are discussed. In view of the importance of exploring the sub-mm and far-infrared wavelengths range for astronomical observations and atmospheric sciences, we present model calculations of the atmospheric transmission for selected telescope sites (DOME-C/Antarctica, ALMA/Chajnantor, JCMT and CSO on Mauna Kea/Hawaii, KOSMA/Swiss Alpes) for frequencies between 0 and 2000 GHz () and typical atmospheric conditions using the forward model MOLIERE (version 5). For the DOME-C site, the transmission over a larger range of up to 10 THz () is calculated in order to demonstrate the quality of an Earth-bound site for mid-IR observations. All results are available on a dedicated webpage.  相似文献   

The Stern Review debate: an editorial essay     

Stephen H. Schneider 《Climatic change》2008,89(3-4):241-244

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Integrated, watershed-based management for sustainable water resources     

Rebecca L. Schneider 《Frontiers of Earth Science》2010,4(1):117-125

Water scarcity is a becoming a critical issue globally, driven largely by the demands of an exponentially growing human population and complicated by the impacts of climate change on the amounts and distribution of precipitation. It is also due to mismanagement as scarce water resources are being used simultaneously for irrigation, power generation, public and industrial water supply, flood reduction, and wastewater disposal without consideration of the cumulative impacts to the water resources themselves. This paper outlines eight ecologically based principles and associated guidelines as the basis for integrated and watershed-based management of the world’s water resources.  相似文献   

<Emphasis Type="Italic">Climatic Change</Emphasis> 100th volume: be careful what you wish for!—what if you get it?     

Stephen H. Schneider 《Climatic change》2010,100(1):1-5

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MegaZ-LRG: a photometric redshift catalogue of one million SDSS luminous red galaxies     

Adrian Collister  Ofer Lahav  Chris Blake  Russell Cannon  Scott Croom  Michael Drinkwater  Alastair Edge  Daniel Eisenstein  Jon Loveday  Robert Nichol  Kevin Pimbblet  Roberto De Propris  Isaac Roseboom  Nic Ross  Donald P. Schneider  Tom Shanks  David Wake 《Monthly notices of the Royal Astronomical Society》2007,375(1):68-76

We describe the construction of MegaZ-LRG, a photometric redshift catalogue of over one million luminous red galaxies (LRGs) in the redshift range  0.4 < z < 0.7  with limiting magnitude   i < 20  . The catalogue is selected from the imaging data of the Sloan Digital Sky Survey (SDSS) Data Release 4. The 2dF-SDSS LRG and Quasar (2SLAQ) spectroscopic redshift catalogue of 13 000 intermediate-redshift LRGs provides a photometric redshift training set, allowing use of ann z, a neural network-based photometric-redshift estimator. The rms photometric redshift accuracy obtained for an evaluation set selected from the 2SLAQ sample is  σ _z = 0.049  averaged over all galaxies, and  σ _z = 0.040  for a brighter subsample  ( i < 19.0)  . The catalogue is expected to contain ∼5 per cent stellar contamination. The ann z code is used to compute a refined star/galaxy probability based on a range of photometric parameters; this allows the contamination fraction to be reduced to 2 per cent with negligible loss of genuine galaxies. The MegaZ-LRG catalogue is publicly available on the World Wide Web from http://www.2slaq.info .  相似文献   

Aspects Of Ring Lasers As Local Earth Rotation Sensors     

U. Schreiber  M. Schneider  C.H. Rowe  G.E. Stedman  W. Schlüter 《Surveys in Geophysics》2001,22(5-6):603-611

Ring laser rotation sensors are best known from inertial navigation, wherethey have many advantages over mechanical gyroscopes. They have recentlybeen greatly improved, and show potential as fully independent length-of-daysensors. We discuss some important aspects of current limitations in theirperformance. In particular we demonstrate a novel scheme for thestabilisation of a large ring laser against frequency pulling effectsinduced by backscatter.  相似文献   

Rhyolithischer Vulkanismus des Südharzer Rotliegenden     

Dr. Alfred Schneider 《Contributions to Mineralogy and Petrology》1963,9(2):148-174

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The Equatorial Ring Current as a Part of a Coupled System     

Van Zele  María Andrea  Schneider  Otto 《Studia Geophysica et Geodaetica》1999,43(3):284-288

The equatorial ring current is the symmetrical plasmaspheric drift current of energetic plasma trapped by the geomagnetic field. Assuming that, during a geomagnetic storm, the ring can exchange energy with other regions of the magnetosphere, a second-order differential equation must be considered as its dynamical expression, and contributions other than the solely solar-wind-induced electric field must express the forced input. The decay parameters of the recovery phase of the storm must be determined considering periods with Bz(IMF) Bz(IMF) 0.  相似文献   

Vulkanismus und Graben-Bildung im Roten Meer     

Dr. W. Schneider  Dr. H. Wachendorf 《International Journal of Earth Sciences》1973,62(3):754-773

Zusammenfassung Von Vulkanit-Proben derValdivia-Kampagnen 1971/72 werden die Ergebnisse petrographischer und chemischer Untersuchungen dargestellt. Im zentralen Graben des Roten Meeres sind Olivin-Tholeiit-Baselte ohne modalen Pyroxen verbreitet. Außerhalb des zentralen Grabens treten neben vorwiegend holokristallinen Pyroxen-führenden Olivin-Tholeiit-Basalten Alkali-Basalte sowie basaltische Tuffe und Hyaloklastite auf. Vergleichsweise wurden Basalte und deren saure Differentiate aus dem Hinterland von Djibouti untersucht. Kristallisations- und Differentiationsgrad der Gesteine sind Abbild eines diapirartig aufgestiegenen Asthenolithen. Die Aufwölbung der Asthenosphäre wird durch die Einsenkung eines Scheitelgrabens kompensiert. Eine Trennung der kontinentalen Kruste betrifft nur den Bereich des zentralen Grabens.

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During theValdivia cruise 1971/72 volcanic fragments were raised from the bottom of the Red Sea, especially from the axial through. Data on petrography and chemistry are represented. The axial trough is floored with olivine-tholeiitic basalts without modal pyroxene. According to the rapid ascent from relatively shallow depth olivinetholeiitic magma reached the sea-floor before any substantial differentiation took place. Beyond the axial trough alkali-basalts, basaltic tuffs, hyaloklastites are distributed as well as olivine-tholeiitic basalts with modal pyroxene. For comparison basalts and their acid differentiates from the hinterland of Djibouti have been analyzed and discussed. The grade of crystallisation and fractionation of the melt is in a direct connection with the diapiric upwelling of the asthenosphere. The upwarped asthenosphere is compensated by normal faulting and rifting of the axial trough. The attenuation and separation of the continental crust is restricted to the axial trough.

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Résumé Pendant les campagnes de laValdivia en 1971/72, des échantillons de volcanites ont été prélevés au fond de la Mer Rouge, à des fins d'analyses pétrographiques et chimiques. Dans le fossé central il y a des basaltes tholéiitiques à olivine sans pyroxène modal. En dehors du fossé central apparaissent des basaltes alcalins, des tufs basaltiques et des hyaloclastites ainsi que des basaltes tholéiitiques à olivine et pyroxène modal prédominemment holocristallins. A titre de comparaison, des basaltes et leurs différenciats acides, prélevés dans le hinterland de Djibouti, ont été analysés. Le degré de cristallisation et de différenciation des roches est en relation avec l'asténolite monté par voie diapirique. Le bombement de l'asténosphère est compensé par l'enfoncement du fossé. La séparation de la croûte continentale est restreinte au fossé axial.

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, 1971/1972 . - . , - , , . . . . .

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Herrn Dr. H.Bäcker von derPreussag AG, Hannover, danken wir für dieÜberlassung des Proben-Materials und für das Einverständnis zur Publikation. Wir danken unseren Kollegen A.Baumann, Braunschweig, und H.Raschka, BfB Hannover, für die Bestimmung der Schwermetall- und Spurenelement-Gehalte sowie den Herren H.Pichler, Tübingen, und A.Schneider, Göttingen, für die Norm-Berechnungen.  相似文献