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201.
This paper presents an input and system identification technique for a soil–structure interaction system using earthquake response data. Identification is carried out on the Hualien large‐scale seismic test structure, which was built in Taiwan for international joint research. The identified quantities are the input ground acceleration as well as the shear wave velocities of the near‐field soil regions and Young's moduli of the shell sections of the structure. The earthquake response analysis on the soil–structure interaction system is carried out using the finite element method incorporating the infinite element formulation for the unbounded layered soil medium and the substructured wave input technique. The criterion function for the parameter estimation is constructed using the frequency response amplitude ratios of the earthquake responses measured at several points of the structure, so that the information on the input motion may be excluded. The constrained steepest descent method is employed to obtain the revised parameters. The simulated earthquake responses using the identified parameters and input ground motion show excellent agreement with the measured responses. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
202.
Rou-Fei Chen Yu-Chang Chan Jacques Angelier Jyr-Ching Hu Chung Huang Kuo-Jen Chang Tian-Yuan Shih 《Comptes Rendus Geoscience》2005,337(13):1164-1172
The 1999 Chi-Chi earthquake triggered the catastrophic Tsaoling landslide in central Taiwan. We mapped the landslide area and estimated the landslide volume, using high-resolution digital elevation model from airborne LiDAR (Light Detection and Ranging), satellite images, aerial photographs and topographic maps. The comparison between cut and fill volumes, about 0.126 and 0.150 km3, respectively, suggests a volume increase of 19% due to decompaction during landsliding. In April 2002, the cut and fill volumes were about 0.137 and 0.116 km3, respectively. These estimates suggest that 2.5 years after the event, the volume of landslide debris removed by river erosion was nearly 0.045 km3. Such a large value highlights the importance of landslide processes for erosion and long-term denudation in the Taiwan mountain belt. To cite this article: R.-F. Chen et al., C. R. Geoscience 337 (2005). 相似文献
203.
The representation of geoscience information for data integration 总被引:17,自引:0,他引:17
In mineral exploration, resource assessment, or natural hazard assessment, many layers of geoscience maps such as lithology, structure, geophysics, geochemistry, hydrology, slope stability, mineral deposits, and preprocessed remotely sensed data can be used as evidence to delineate potential areas for further investigation. Today's PC-based data base management systems, statistical packages, spreadsheets, image processing systems, and geographical information systems provide almost unlimited capabilities of manipulating data. Generally such manipulations make a strategic separation of spatial and nonspatial attributes, which are conveniently linked in relational data bases. The first step in integration procedures usually consists of studying the individual charateristics of map features and interrelationships, and then representing them in numerical form (statistics) for finding the areas of high potential (or impact).Data representation is a transformation of our experience of the real world into a computational domain. As such, it must comply with models and rules to provide us with useful information. Quantitative representation of spatially distributed map patterns or phenomena plays a pivotal role in integration because it also determines the types of combination rules applied to them.Three representation methods—probability measures, Dempster-Shafer belief functions, and membership functions in fuzzy sets—and their corresponding estimation procedures are presented here with analyses of the implications and of the assumptions that are required in each approach to thematic mapping. Difficulties associated with the construction of probability measures, belief functions, and membership functions are also discussed; alternative procedures to overcome these difficulties are proposed. These proposed techniques are illustrated by using a simple, artificially constructed data set. 相似文献
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保安林分布遍及全台湾省,但在自然与社会环境的变迁下,民众对土地资源需求日益迫切,区外保安林常遭非法使用,因此如何有效地订定经营决策,为经营者应注视之问题。本研究以垦丁公园辖区之区外保安林为研究范围,利用1993与2001年SPOT卫星遥测影像为材料,并用监督性分类法中之最大概似法进行影像分类,建立都市、森林、农耕地等3种土地利用类型,分类结果提供监测1993至2001年间保安林之土地变迁。此外保安林地受人为之冲击评估乃采用分类之结果与地理信息系统之空间分析技术,配合保安林地之开发地成长率、农耕地开垦率及保安林地受人为潜在开发率等冲击指标,评估垦丁公园境内各编号保安林所受到的人为冲击。研究结果显示,共有8处保安林所受之冲击最为严重,值得管理者加以重视。 相似文献
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Natural Hazards - Many countries aim to efficiently allocate limited national research and development resources to produce optimal research. A proportion of limited national research and... 相似文献
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Ki-Hoon Song Ki-Young Choi Chang-Joon Kim Young-Il Kim Chang-Soo Chung 《Ocean Science Journal》2015,50(4):721-740
As with many countries, the Korea government has made a variety of efforts to meet the precautionary principle under the London Convention and Protocol acceded in 1994 and 2009. However, new strategies for the suitable marine dumping of waste materials have since been developed. In this study, the distribution and contamination of heavy metals including Al, Fe, Mn, Li, Co, Cr, Ni, Cu, Zn, As, Cd, Pb and Hg in bottom sediments were analyzed and compared to various criteria in order to evaluate the effectiveness of the management of the East Sea-Jung (ES-Jung) dumping site by the Korea government. The results indicate that the average metal concentrations were significantly lower than Effects Range Low (ERL) values, and generally similar to or lower than the Threshold Effect Levels (TEL) from the Sediment Quality Guidelinces (SQGs). According to analyses of various metal contamination indexes (Enrichment Factor: EF, Pollution Load Index: PLI and the Index of Geoaccumulation: Igeo), most areas were found to be uncontaminated by heavy metals with the exception of several moderately contaminated stations (ESJ 33, 54, 64 and ESJR 20). Heavy metal concentrations in areas grouped as G1, G2, DMDA, N-Ref and S-Ref which showed similar characteristics between 2007-2013 and 2014, were compared. Unexpectedly, most concentrations in the northern reference area (N-Ref) were much higher than those in the actual dumping areas (G1 and G2), may be due to the influences from nearby cities to the west of the ES-Jung site, rather than from the dumping site itself. Additionally, heavy metal concentrations in the dredged material dumping area (DMDA) were found to be low although they have slightly increased over time and those in the southern reference area (S-Ref) were found to have gradually decreased with year. The concentrations of most metals in the East Sea-Jung dumping site were similar to or less than those in the Earth’s crust and approximately the same as those in continental sediments. As a result, this site can be considered as uncontaminated or slightly contaminated. This implies that the efforts made by the Korea government to manage and govern the dumping site through various policies, including ‘the focal point system’, ‘the responsibility zones system’ and ‘the principle of pollution causing party liability’, have been successful. 相似文献