Monte Carlo Markov Chain parameter estimation in semi-analytic models of galaxy formation     

Bruno M. B. Henriques  Peter A. Thomas  Seb Oliver  Isaac Roseboom 《Monthly notices of the Royal Astronomical Society》2009,396(1):535-547

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Coordinated Study on Solar Wind Turbulence During the Venus-Express, ACE and Ulysses Alignment of August 2007     

R. Bruno  V. Carbone  Z. Vörös  R. D’Amicis  B. Bavassano  M. B. Cattaneo  A. Mura  A. Milillo  S. Orsini  P. Veltri  L. Sorriso-Valvo  T. Zhang  H. Biernat  H. Rucker  W. Baumjohann  D. Jankovičová  P. Kovács 《Earth, Moon, and Planets》2009,104(1-4):101-104

At the end of August 2007, Venus, Earth and Ulysses were aligned within a few degrees. This unusual event gives the opportunity to attempt a coordinated study on the radial evolution of solar wind turbulence and coronal transients like CMEs between 0.7 and 1.4 AU. Interplanetary magnetic field data and moments of proton velocity distribution function such as density, speed and temperature are required for this programme and will be provided by ACE at Earth, Venus Express at Venus and Ulysses at 1.4 AU. This project has been recently proposed as a Coordinated Investigation Programme (CIP35) for the International Heliophysical Year.  相似文献   

Discussion on “Effects of different drying rates on shrinkage characteristics of a residual soil and soil mixtures” by Henry Krisdani, Harianto Rahardjo, Eng-Choon Leong [Engineering Geology 102 (2008) 31–37]     

Mamert Mbonimpa  Michel Aubertin  Bruno Bussire 《Engineering Geology》2009,107(3-4):172-173

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Rapid and cyclic aeolian deposition during the Last Glacial in European loess: a high-resolution record from Nussloch, Germany   总被引：1，自引：0，他引：1  

Pierre Antoine  Denis-Didier Rousseau  Olivier Moine  Stphane Kunesch  Christine Hatt  Andreas Lang  Hlne Tissoux  Ludwig Zller 《Quaternary Science Reviews》2009,28(25-26):2955-2973

This paper reports the results of an investigation of the Weichselian Upper Pleniglacial loess sequences of Nussloch (Rhine Valley, Germany) based on stratigraphy, palaeopedology, sedimentology, palynology, malacology and geochemistry (δ¹³C), supported by radiocarbon, TL and OSL dating. Grain-size and magnetic susceptibility records are taken at 5 cm intervals from the Upper Pleniglacial (UPG) loess. The data indicate cyclic variations in loess deposition between ca 34 and 17 ka, when the sedimentation rate is especially high (1.0–1.2 m per ka for more than 10 m). The grain-size index (GSI: ratio of coarse silt versus fine silt and clay) shows variations, which are assumed to be an indirect measurement of wind intensity. The sedimentation rate, interpreted from the profiles, indicates high values in loess (Loess events LE-1 to LE-7) and low or negligible values in tundra gley horizons G1 to G8. OSL ages from the loess and ¹⁴C dates from organic matter in the loess show that loess deposition was rapid but was interrupted by shorter periods of reduced aeolian sedimentation. Comparison between the data from Nussloch and other European sequences demonstrates a progressive coarsening of the loess deposits between ca 30 and 22 ka. This coarsening trend ends with a short but major grain-size decrease and is followed by an increase to a new maximum at 20 ± 2 ka (“W” shape). Correlation between the loess GSI and the Greenland ice-core dust records, suggests a global connection between North Atlantic and Western European global atmospheric circulation and wind regimes. In addition, the typical Upper Pleniglacial loess deposition begins at ca 30–31 ka, close to Heinrich event (HE) 3, and the main period of loess sedimentation at about 25 ± 2 ka is coeval to HE 2. Correlation of magnetic susceptibility and grain-size records shows that the periods, characterised by high GSI, coincide with an increase in the amount of ferromagnetic minerals reworked from the Rhine alluvial plain. They suggest enhancement in the frequency of the storms from N–NW. These results are integrated within a palaeogeographical model of dust transport and deposition in Western Europe for the Weichselian Upper Pleniglacial (or Late Pleniglacial).  相似文献   

AVES: A high performance computer cluster array for the INTEGRAL satellite scientific data analysis     

Memmo Federici  Bruno Luigi Martino  Pietro Ubertini 《Experimental Astronomy》2012,34(1):105-121

In this paper we describe a new computing system array, designed, built and now used at the Space Astrophysics and Planetary Institute (IAPS) in Rome, Italy, for the INTEGRAL Space Observatory scientific data analysis. This new system has become necessary in order to reduce the processing time of the INTEGRAL data accumulated during the more than 9 years of in-orbit operation. In order to fulfill the scientific data analysis requirements with a moderately limited investment the starting approach has been to use a ??cluster?? array of commercial quad-CPU computers, featuring the extremely large scientific and calibration data archive on line.  相似文献   

Investigating Ionospheric Scintillation Effects on Multifrequency GPS Signals     

Salles  Lucas A.  Vani  Bruno C.  Moraes  Alison  Costa  Emanoel  de Paula  Eurico R. 《Surveys in Geophysics》2021,42(4):999-1025

Surveys in Geophysics - Over the last 15 years, the satellite constellation of the global positioning system (GPS) has been modernized for more precise applications, with the introduction...  相似文献   

Mantle source heterogeneity in subduction zones: constraints from elemental and isotope (Sr,Nd, and Pb) data on Vulcano Island,Aeolian Archipelago,Italy     

Pinarelli  Laura  Gioncada  Anna  Capaccioni  Bruno  Vaselli  Orlando  Downes  Hilary 《Mineralogy and Petrology》2019,113(1):39-60

Mineralogy and Petrology - Vulcano is part of the Aeolian volcanic arc in the southern Tyrrhenian Sea. Its products were emplaced through multiple episodes of edifice building and collapse since...  相似文献   

Do static stress changes of a moderate‐magnitude earthquake significantly modify the regional seismic hazard? Hints from the L'Aquila 2009 normal‐faulting earthquake (Mw 6.3, central Italy)     

Bruno Pace  Gian Maria Bocchini  Paolo Boncio 《地学学报》2014,26(6):430-439

We investigated the Coulomb stress changes in the active faults surrounding a moderate‐magnitude normal‐faulting earthquake (2009 L'Aquila, Mw 6.3) and the associated variations in the expected ground motion on regional probabilistic seismic hazard maps. We show that the static stress variations can locally increase the seismic hazard by modifying the expected mean recurrence time on neighbouring faults by up to ~290 years, with associated variations in the probability of occurrence of the maximum expected earthquake of up to ~2%. Our findings suggest that the increase in seismic hazard on neighbouring faults following moderate‐magnitude earthquakes is probably not sufficient to necessitate systematic upgrades of regional probabilistic seismic hazard maps, but must be considered to better address and schedule strategies for local‐scale mitigation of seismic risk.  相似文献   

Identification of groundwater mean transit times of precipitation and riverbank infiltration by two‐component lumped parameter models     

Nguyen Le Duy  Nguyen Viet Dung  Ingo Heidbüchel  Hanno Meyer  Markus Weiler  Bruno Merz  Heiko Apel 《水文研究》2019,33(24):3098-3118

Groundwater transit time is an essential hydrologic metric for groundwater resources management. However, especially in tropical environments, studies on the transit time distribution (TTD) of groundwater infiltration and its corresponding mean transit time (mTT) have been extremely limited due to data sparsity. In this study, we primarily use stable isotopes to examine the TTDs and their mTTs of both vertical and horizontal infiltration at a riverbank infiltration area in the Vietnamese Mekong Delta (VMD), representative of the tropical climate in Asian monsoon regions. Precipitation, river water, groundwater, and local ponding surface water were sampled for 3 to 9 years and analysed for stable isotopes (δ¹⁸O and δ²H), providing a unique data set of stable isotope records for a tropical region. We quantified the contribution that the two sources contributed to the local shallow groundwater by a novel concept of two‐component lumped parameter models (LPMs) that are solved using δ¹⁸O records. The study illustrates that two‐component LPMs, in conjunction with hydrological and isotopic measurements, are able to identify subsurface flow conditions and water mixing at riverbank infiltration systems. However, the predictive skill and the reliability of the models decrease for locations farther from the river, where recharge by precipitation dominates, and a low‐permeable aquitard layer above the highly permeable aquifer is present. This specific setting impairs the identifiability of model parameters. For river infiltration, short mTTs (<40 weeks) were determined for sites closer to the river (<200 m), whereas for the precipitation infiltration, the mTTs were longer (>80 weeks) and independent of the distance to the river. The results not only enhance the understanding of the groundwater recharge dynamics in the VMD but also suggest that the highly complex mechanisms of surface–groundwater interaction can be conceptualized by exploiting two‐component LPMs in general. The model concept could thus be a powerful tool for better understanding both the hydrological functioning of mixing processes and the movement of different water components in riverbank infiltration systems.  相似文献   

Der Einfluß der Vegetation auf die Schwankungen des CO2-Gehaltes der Atmosphäre     

Bruno Huber 《Theoretical and Applied Climatology》1952,4(2):154-167

Zusammenfassung Mit Hilfe des Ultrarot-Absorptionsschreibers wurden Tagesgänge des CO₂-Gehaltes in verschiedenen Höhen über einem Weizenfeld registriert. Während sich nachts durch die Atmung der Vegetation CO₂ am Boden anreichert, verarmt die bodennahe Luftschicht tagsüber infolge der Assimilation an CO₂. Das CO₂-Gefälle wechselt demnach zweimal täglich (morgens und abends) sein Vorzeichen. Infolge größerer Turbulenz ist das Gefälle bei Tag kleiner als bei Nacht; nach Multiplikation mit der Windgeschwindigkeit als Relativmaß des Austausches ergeben sich aber glaubhafte Relativwerte für den vertikalen CO₂-Strom und damit für die Kohlenstoffbindung und-entbindung durch die Pflanzendecke.

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Summary With the help of an infrared absorption-recorder the daily variation of CO₂ content in different heights above a wheat field has been recorded. During the night the CO₂ content is accumulated at the plant level by respiration, during the day diminished by photosynthesis. The CO₂ gradient thus changes its sign (+ or –) twice a day in the morning and evening. The CO₂ gradient is smaller during the day than in the night due to the stronger turbulence of the air. In multiplying gradients with wind velocities (used as a measure for the eddy exchange) one gets reasonable relative values for the vertical CO₂-stream, and thus also for photosynthesis and respiration of vegetation.

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Résumé La variation diurne de la teneur de l'air en CO₂ a été mesurée à différentes hauteurs au-dessus d'un champ de froment à l'aide d'un appareil enregistreur de l'absorption à l'infra-rouge. Tandis que cette teneur augmente de nuit au voisinage du sol par la respiration végétale, elle diminue au cours du jour par suite de l'assimilation. Le gradient vertical de la teneur en CO₂ change par conséquent de signe deux fois par jour, le matin et le soir; il est plus faible de jour à cause de la turbulence accrue que de nuit. Après multiplication par la vitesse du vent, mesure relative de l'échange turbulent, on obtient des valeurs relatives mais vraisemblables du courant vertical de CO₂ et par conséquent de la fixation et de la libération du carbone par la végétation.

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Mit 7 Textabbildungen.

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Nach einem am 15. Oktober 1951 auf der Meteorologentagung in Bad Kissingen gehaltenen Vortrag.  相似文献