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181.
Conversion of Industry Foundation Classes (IFC) building models into CityGML city models is one of the operational scenarios for BIM–GIS integration, with a variety of applications producing and consuming data on either side. Given the in‐depth cross‐domain knowledge required to specify such conversions, the heterogeneity of the IFC input data and the use cases for the resulting CityGML, flexible and configurable solutions are needed that make conversion details accessible to domain specialists. Graph transformation as a conversion method fulfils these requirements. We propose to extend the modularity given by single transformation rules at a more coarse‐grained level and identify four layers with modules of associated rules. We describe a self‐contained set of rules across these modules and demonstrate its application to a range of building models.  相似文献   
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Indonesia as an archipelagos country consisting of more than 17,508 islands has a challenging problem in terms of island management and the provisional ocean services to the coastal community. The population growth (especially in coastal areas) followed by declining natural resources caused by overfishing and overexploitation is one of the biggest concerns both for the central and the local governments in Indonesia. Integrated Coastal Zone Management (ICZM) is one of the attempted solutions to overcome these difficulties, however, it is known to be unsatisfactory even after several programs under ICZM have been developed and implemented. Therefore, further facilitation of ICZM programs is necessary in order to benefit to Indonesian governmental management of their islands, coastal areas and oceans. In doing so, ICZM will also make a significant contribution towards the implementation of the Indonesia Global Ocean Observing System (INA-GOOS). This paper aims to review ICZM activities in Indonesia to obtain a better understanding of, and the need for ICZM implementations in support of their policy, sustainability and decision-making process in the direction of INA-GOOS. It is expected that the ICZM implementations will have a high impact on INA-GOOS programs.  相似文献   
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We have performed spherically symmetric and axisymetric hydrodynamic simulations of wind–clump interactions in order to determine the conditions under which a wind, impacting upon a clump and increasing in power with time, drives a strong shock into the clump. If the wind ram pressure and the clump thermal pressure are comparable when the impact first occurs, then the wind ram pressure must increase on a time-scale markedly smaller than the sound-crossing time of the clump if it is to drive a shock that becomes strong at any point in the clump. We comment on the possible relevance of this result for the dynamics and chemistry of hot cores in regions of high-mass star formation.  相似文献   
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Abstract— Asteroid and comet impacts can have a profound influence on the habitats available for lithophytic microorganisms. Using evidence from the Haughton impact structure, Nunavut, Canadian High Arctic, we describe the role of impacts in influencing the nature of the lithophytic ecological niche. Impact‐induced increases in rock porosity and fracturing can result in the formation of cryptoendolithic habitats. In some cases and depending upon the target material, an increase in rock translucence can yield new habitats for photosynthetic cryptoendoliths. Chasmoendolithic habitats are associated with cracks and cavities connected to the surface of the rock and are commonly increased in abundance as a result of impact bulking. Chasmoendolithic habitats require less specific geological conditions than are required for cryptoendolithic habitats, and their formation is likely to be common to most impact events. Impact events are unlikely to have an influence on epilithic and hypolithic habitats except in rare cases, where, for example, the formation of impact glasses might yield new hypolithic habitats. We present a synthetic understanding of the influence of asteroid and comet impacts on the availability and characteristics of rocky habitats for microorganisms.  相似文献   
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Regional projection of future extreme wave heights around Korean Peninsula   总被引:1,自引:0,他引:1  
In this study, future changes in regional extreme wave heights around the Korean Peninsula are projected by using the results of an atmosphere general circulation model and a third-generation wave model. The direct use of the model output at each grid point is not appropriate even though high resolution of 20 km is used for the models. Therefore, the model output is grouped into six regions around the Korean Peninsula. The grouping approach is reasonable in assessing climate change effects with alleviated model uncertainty. The extreme wave heights are simulated for two climate periods of 1979–2003 (present climate) and 2075–2099 (future climate). The model results are validated by comparing the simulated wave heights for the present climate with observed and hindcasted wave data. The extreme wave heights for the future climate are then projected for different seasons and in different regions. The 50-year return wave height in summer is projected to increase in most regions, especially in the high-latitude Yellow Sea and the East Sea, while the wave height in winter is projected to decrease in all the regions, especially in the East Sea.  相似文献   
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This paper discusses the hydrochemistry variation and its quality status in Langat River, based on the chemistry of major ions, metal concentrations and suitability for drinking purposes. Water samples were collected from 30 different stations to assess their hydrochemical characteristics. The physico-chemical parameters selected were temperature, electrical conductivity, total dissolved solids (TDS), salinity, dissolved oxygen , pH, redox potential, HCO3, Cl, SO4, NO3, Ca, Na, K, Mg, 27Al, 138Ba, 9Be, 111Cd, 59Co, 63Cu, 52Cr, 57Fe, 55Mn, 60Ni, 208Pb, 80Se and 66Zn to investigate the variation of the constituents in the river water. Most of the parameters comply with the Drinking Water Quality Standard of the World Health Organization and the Malaysian National Standard for Drinking Water Quality by the Malaysia Ministry of Health except for EC, TDS, Cl, HCO3, SO4, Na, Mg, Al, Fe and Se. The results show that the Langat River is unsuitable for drinking purposes directly without treatment.  相似文献   
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