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1.
In model inter-comparisons one major obstacle is the format of the reported data. To facilitate the analysis of the results from the different models they should all be reported in the same format. This requires that the format is flexible enough to be easily implemented into the different land surface schemes. It should also be fault tolerant and allow a few consistence checks to avoid erroneous data to be submitted. The present note describes such a format developed for the PILPS project. After discussing the aim of this new format we present the routines which are used to write and read data. Finally two applications are described which allow the user to perform a number of consistency checks on the data. 相似文献
2.
罗卫敏 《成都信息工程学院学报》2004,19(2):209-213
针对信息系统安全的考虑,介绍在PowerBuilder环境中对用户权限的具体控制. 相似文献
3.
A constitutive relation is derived for describing the mechanical response of chalk. The approach is based on a phenomenological framework which employs chemo‐plasticity. The properties of the material are assumed to be affected by the physico‐chemical processes that occur through the interaction between the skeleton and the pore fluid. The underlying mechanism is discussed by invoking a micromechanical analysis. The performance of the framework is illustrated by examining the evolution of mechanical characteristics in the presence of different pore fluids. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
4.
本文提出了一个普适的衡量成团天体系统成员概率计算结果的有效性指数:E=1-NΣ{P(i)[1-P(i)]}/ΣP(i)Σ[1-P(i)]},并以此对以Sanders方法为基础的各种成员确定模型的有效性进行了分析.从总体上说,运动学资料(自行、视向速度等)是一类有效的观测判据. 相似文献
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Application of MODFLOW and geographic information system to groundwater flow simulation in North China Plain, China 总被引:2,自引:0,他引:2
Shiqin Wang Jingli Shao Xianfang Song Yongbo Zhang Zhibin Huo Xiaoyuan Zhou 《Environmental Geology》2008,55(7):1449-1462
MODFLOW is a groundwater modeling program. It can be compiled and remedied according to the practical applications. Because
of its structure and fixed data format, MODFLOW can be integrated with Geographic Information Systems (GIS) technology for
water resource management. The North China Plain (NCP), which is the politic, economic and cultural center of China, is facing
with water resources shortage and water pollution. Groundwater is the main water resource for industrial, agricultural and
domestic usage. It is necessary to evaluate the groundwater resources of the NCP as an entire aquifer system. With the development
of computer and internet information technology it is also necessary to integrate the groundwater model with the GIS technology.
Because the geological and hydrogeological data in the NCP was mainly in MAPGIS format, the powerful function of GIS of disposing
of and analyzing spatial data and computer languages such as Visual C and Visual Basic were used to define the relationship
between the original data and model data. After analyzing the geological and hydrogeological conditions of the NCP, the groundwater
flow numerical simulation modeling was constructed with MODFLOW. On the basis of GIS, a dynamic evaluation system for groundwater
resources under the internet circumstance was completed. During the process of constructing the groundwater model, a water
budget was analyzed, which showed a negative budget in the NCP. The simulation period was from 1 January 2002 to 31 December
2003. During this period, the total recharge of the groundwater system was 49,374 × 106 m3 and the total discharge was 56,530 × 106 m3 the budget deficit was −7,156 × 106 m3. In this integrated system, the original data including graphs and attribution data could be stored in the database. When
the process of evaluating and predicting groundwater flow was started, these data were transformed into files that the core
program of MODFLOW could read. The calculated water level and drawdown could be displayed and reviewed online. 相似文献
7.
N. M. Sushchevskaya A. N. Evdokimov B. V. Belyatsky V. A. Maslov D. V. Kuz’min 《Geochemistry International》2008,46(1):1-16
Petrological and geochemical data obtained on the Quaternary lavas of volcanoes at Spitsbergen Island indicate that the rocks were produced via the deep-seated crystallization of parental alkaline magmas at 8–10 kbar. The character of clinopyroxene enrichment in incompatible elements indicates that the mineral crystallized from more enriched melts than those inferred from the composition of the host lavas. These melts were close to the parental melts previously found as veinlets in mantle hyperbasite xenoliths in the lavas. According to the character of their enrichment in Pb and Sr radiogenic isotopes and depletion in Nd, the basalts from Spitsbergen Island define a single trend with the weakly enriched tholeiites of the Knipovich Ridge, a fact suggesting the closeness of the enriched sources beneath the continental margin of Spitsbergen and beneath the spreading zone. Magmatic activity at Spitsbergen was related to the evolution of the Norwegian-Greenland basin, which evolved in pulses according to the shift of the spreading axes. The most significant of the latter events took place in the Neogene, when the Knipovich Ridge obtained its modern position near the western boundary of Spitsbergen. Early in the course of the evolution, the emplacement of alkaline melts generated at Spitsbergen into the oceanic mantle could form the enriched mantle, which was later involved in the melting process beneath the spreading zone. 相似文献
8.
3D models of apparent magnetization and density of rocks allow us to provide insights into the deep structure of the Volga-Ural, Pericaspian, and Fore-Caucasus petroliferous basins. In the Volga-Ural Basin, some Riphean rifts reveal close spatial relations to Paleoproterozoic linear zones, presumably of the rift nature as well. The structure of the Paleoproterozoic Toropets-Serdobsk Belt is interpreted in detail. Rocks with petrophysical properties inherent to basic volcanics are established in the pre-Paleozoic basement of the marginal zone of the Pericaspian Basin. These rocks locally spread beyond the boundary escarpment and may be regarded as a part of the Riphean plume-related basaltic province. It is shown that the Pericaspian Basin was formed on the place of a triple junction of Riphean rifts: the Sarpa and Central Pericaspian oceanic branches and the continental branch of the Pachelma Aulacogen. The drastically different petrophysical properties of the basement beneath Baltica and the Astrakhan Arch indicate that this arch is an element of the large terrane that was attached to Baltica in the Vendian. The suture along which the Astrachan Terrane is conjugated with the basement of the central and southern segments of the Karpinsky Ridge is traced beneath the Paleozoic complex. A system of northwest-verging thrust faults formed during the collision between Scythia and Eurasia is mapped in the basement of the junction zone between the Karpinsky Ridge and Scythian Platform (Terrane). According to geological data, this event took place in the Early Paleozoic. 相似文献
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