The Emergence of Digital Twins in Remediation: How Platform Synchrony Will Change the Model for Delivery     

John Horst  Nick Welty  Allison Yanites  Francois Appere  Monica Dupre  Shahansha Shaik 《Ground Water Monitoring & Remediation》2020,40(3):14-20

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Qualitätssicherung beim chemischen Meeresmonitoring     

Woitke  Peter  Gaul  Horst 《Ocean Dynamics》1999,51(10):171-177

Ocean Dynamics - Für eine Bewertung des Zustands der Meeresumwelt sind die Richtigkeit und die Vergleichbarkeit der im marinen Monitoring erhobenen Daten wesentliche Voraussetzungen. Ein...  相似文献   

Testing the blast wave model with Swift GRBs     

P. A. Curran  R. L. C. Starling  A. J. van der Horst  R. A. M. J. Wijers 《Monthly notices of the Royal Astronomical Society》2009,395(1):580-592

The complex structure of the light curves of Swift Gamma-Ray Bursts (GRBs) has made the identification of breaks, and the interpretation of the blast wave caused by the burst, more difficult than in the pre- Swift era. We aim to identify breaks, which are possibly hidden, and to constrain the blast wave parameters; electron energy distribution, p , density profile of the circumburst medium, k , and the continued energy injection index, q . We do so by comparing the observed multiwavelength light curves and X-ray spectra of our sample to the predictions of the blast wave model. We can successfully interpret all of the bursts in our sample of 10, except two, within this framework and we can estimate, with confidence, the electron energy distribution index for 6 of the sample. Furthermore, we identify jet breaks in a number of the bursts. A statistical analysis of the distribution of p reveals that, even in the most conservative case of least scatter, the values are not consistent with a single, universal value. The values of k suggest that the circumburst density profiles are not drawn from only one of the constant density or wind-like media populations.  相似文献   

Ground-based calibration and characterization of the Fermi gamma-ray burst monitor detectors     

E. Bissaldi  A. von Kienlin  G. Lichti  H. Steinle  P. N. Bhat  M. S. Briggs  G. J. Fishman  A. S. Hoover  R. M. Kippen  M. Krumrey  M. Gerlach  V. Connaughton  R. Diehl  J. Greiner  A. J. van der Horst  C. Kouveliotou  S. McBreen  C. A. Meegan  W. S. Paciesas  R. D. Preece  C. A. Wilson-Hodge 《Experimental Astronomy》2009,24(1-3):47-88

One of the scientific objectives of NASA’s Fermi Gamma-ray Space Telescope is the study of Gamma-Ray Bursts (GRBs). The Fermi Gamma-Ray Burst Monitor (GBM) was designed to detect and localize bursts for the Fermi mission. By means of an array of 12 NaI(Tl) (8 keV to 1 MeV) and two BGO (0.2 to 40 MeV) scintillation detectors, GBM extends the energy range (20 MeV to > 300 GeV) of Fermi’s main instrument, the Large Area Telescope, into the traditional range of current GRB databases. The physical detector response of the GBM instrument to GRBs is determined with the help of Monte Carlo simulations, which are supported and verified by on-ground individual detector calibration measurements. We present the principal instrument properties, which have been determined as a function of energy and angle, including the channel-energy relation, the energy resolution, the effective area and the spatial homogeneity.  相似文献   

Man's role in changing the coastal landscapes in Denmark     

Horst Meesenburg 《GeoJournal》1996,39(2):143-151

This article describes the influence of man on the coastal landscapes along the Danish and part of the German west coast. While the tidal coast south of Blåvandshuk was formed by man since premedieval times, the northern part of Jutlands coast nearly avoided human influence until the late 19th century when dune plantation and coast protection was begun. At the same time, the first harbours were built by the Danish state, mainly for fishing purposes. The human influence increased through the 20th century, with tourism as a main factor. The article highlights the radical changes and the fragile balance between human action and natural processes on a debris coast. The article summarizes some of the authors contributions in the Danish landscape magazine Bygd, of which he is editor.  相似文献   

Footprint estimation for scalar flux measurements in the atmospheric surface layer   总被引：12，自引：2，他引：12  

T. W. Horst  J. C. Weil 《Boundary-Layer Meteorology》1992,59(3):279-296

The flux footprint is the contribution, per unit emission, of each element of a surface area source to the vertical scalar flux measured at height z _m ; it is equal to the vertical flux from a unit surface point source. The dependence of the flux footprint on crosswind location is shown to be identical to the crosswind concentration distribution for a unit surface point source; an analytic dispersion model is used to estimate the crosswind-integrated flux footprint. Based on the analytic dispersion model, a normalized crosswind-integrated footprint is proposed that principally depends on the single variable z/z _m , where z is a measure of vertical dispersion from a surface source. The explicit dependence of the crosswind-integrated flux footprint on downwind distance, thermal stability and surface roughness is contained in the dependence of z on these variables. By also calculating the flux footprint with a Lagrangian stochastic dispersion model, it is shown that the normalized flux footprint is insensitive to the analytic model assumption of a self-similar vertical concentration profile.The National Center for Atmospheric Research is funded by the National Science Foundation.  相似文献   

Intercomparison of sediment sampling techniques by means of radionuclide and heavy metal analysis     

Dr. Hartmut Nies  Dr. Horst Albrecht  Volker Rechenberg  Ingo Goroncy  Dr. Henning Dahlgaard  Dietmar Weiß  Prof. Dr. Lutz Brügmann 《Ocean Dynamics》1990,43(1):27-53

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Detrital,metamorphic and metasomatic tourmaline in high-pressure metasediments from Syros (Greece): intra-grain boron isotope patterns determined by secondary-ion mass spectrometry     

Horst R. Marschall  Rainer Altherr  Angelika Kalt  Thomas Ludwig 《Contributions to Mineralogy and Petrology》2008,155(6):703-717

The boron isotopic composition of zoned tourmaline in two metasediments from the island of Syros, determined by secondary-ion mass spectrometry (SIMS), reflects the sedimentary and metamorphic record of the rocks. Tourmaline from a silicate-bearing marble contains small (≤20 μm) detrital cores with highly variable δ ¹¹B values (−10.7 to +3.6‰), pointing to a heterogeneous protolith derived from multiple sources. The sedimentary B isotopic record survived the entire metamorphic cycle with peak temperatures of ∼500°C. Prograde to peak metamorphic rims are homogeneous and similar among all analysed grains (δ ¹¹B ≈ +0.9‰). The varying δ ¹¹B values of detrital cores in the siliceous marble demonstrate that in situ B isotope analysis of tourmaline by SIMS is a potentially powerful tool for provenance studies not only in sediments but also in metasediments. A meta-tuffitic blueschist bears abundant tourmaline with dravitic cores of detrital or authigenic origin (δ ¹¹B ≈ −3.3‰), and prograde to peak metamorphic overgrowth zones (−1.6‰). Fe-rich rims, formed during influx of B-bearing fluids under retrograde conditions, show strongly increasing δ ¹¹B values (up to +7.7‰) towards the margins of the grains. The δ ¹¹B values of metamorphic tourmaline from Syros, formed in mixed terrigenous–marine sediments, reflect the B signal blended from these two different sources, and was probably not altered by dehydration during subduction.  相似文献   

Coronal holes and icosahedral symmetry     

Herbert Kalisch  Wolfram Neutsch  Horst Fichtner  S. Ranga Sreenivasan  Maurice Shevalier 《Astrophysics and Space Science》2003,288(4):445-469

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Second-degree Stokes coefficients from multi-satellite SLR   总被引：1，自引：1，他引：0  

Mathis Bloßfeld  Horst Müller  Michael Gerstl  Vojtěch Štefka  Johannes Bouman  Franziska Göttl  Martin Horwath 《Journal of Geodesy》2015,89(9):857-871

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