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排序方式: 共有719条查询结果,搜索用时 343 毫秒
101.
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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
103.
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
104.
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
105.
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
106.
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
107.
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.
Mit 7 Textabbildungen.
Nach einem am 15. Oktober 1951 auf der Meteorologentagung in Bad Kissingen gehaltenen Vortrag. 相似文献
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.
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.
Mit 7 Textabbildungen.
Nach einem am 15. Oktober 1951 auf der Meteorologentagung in Bad Kissingen gehaltenen Vortrag. 相似文献
108.
Bruno Simmersbach 《International Journal of Earth Sciences》1920,10(4-8):158-182
Ohne Zusammenfassung 相似文献
109.
110.