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991.
GIS-based distributed technique for assessing economic loss from flood damage: pre-feasibility study for the Anyang Stream Basin in Korea 总被引:4,自引:4,他引:0
Large national budgets are required for flood damage reduction projects, making it critical to ensure that public money used
therein be spent efficiently. Accordingly, reliable assessment of flood damage is a critical issue in analysis of the economic
aspects of flood damage reduction projects. To this end, this study aims to provide a GIS (geographical information system)-based
technique for distributed flood damage assessment. We consider two aspects of flood damage assessment from an engineering
and economic perspective, i.e. flood inundation analysis and multi-dimensional flood damage analysis (MD-FDA). To perform
this assessment, we used a GIS-based framework and data processing method to assess damages. The proposed methodology was
applied to flood control channel projects for flood disaster prevention in the Anyang Stream Basin in Korea and presents detailed
GIS data processing and assessment results. Findings from this study may contribute to the improvement of usability of MD-FDA
and may provide research directions for integrating economic and engineering factors. This distributed technique will also
assist in the decision-making process when evaluating the economic feasibility of flood damage reduction projects for structural
and non-structural measures. 相似文献
992.
鄂尔多斯盆地晚三叠世湖盆西南缘及东北缘发育典型坳陷型湖盆坡折带。研究表明,在北东缘具有多级缓坡坡折带特征,坡度1°~3°,宽度15~25 km;西南缘具有单一陡坡坡折带特征,坡度3°~5°,宽度10~20 km。由于受湖盆收缩原因影响,坡折带平面展布局部会发生变化。与此同时,坡折带在对地层的超覆叠置、岩性纵向组合以及沉积体的纵横向展布上均具有重要的控制作用。以坡折带特征研究为基础,建立坡折带控制非构造圈闭展布模式,对于指导鄂尔多斯盆地晚三叠世地层的油气勘探具有重要意义。 相似文献
993.
994.
995.
根据粘土矿物含量的图版计算方法,计算了实际井段的粘土矿物含量,分析了高岭石、伊利石和蒙脱石与U、Th、K含量的相关关系,由此分析得到粘土矿物含量与放射性元素含量的多元线性关系,建立了粘土矿物含量计算的回归方程。通过对不同井段以及同一井段不同地层数据建立的回归方程分析,给出了具有代表性的线性回归方程模型。根据一个实际井段粘土矿物的计算,获得粘土矿物含量随深度的变化,其粘土矿物含量计算结果与原测井解释相吻合,同时与岩心分析误差在10%左右。 相似文献
996.
A sea-survey was carried out along the Chinese coast from the Bohai Sea to South China Sea, and 15 surficial samples were
taken from major coastal estuaries, i.e., from north to south, the Yellow, abandoned Yellow, Yangtze, Qiantang, Ou, Min, Han,
and Pearl River estuaries. On the basis of clay mineral analysis and published data collection, this paper discusses the characteristics
of clay minerals of each coastal river and potentials of implications of sediment sources. The results show that the change
of diagnostic clay minerals from smectite to kaolinite from the Yellow to the Pearl River estuaries is southward, as clearly
shown by the ratios of smectite to chlorite (S/Ch) and kaolinite to illite (K/I). S/Ch decreases southward, while K/I moves
reversely, implying change in climate setting from cool/dry to humid/hot with intensified weathering processes. Besides, these
two indicators in the estuaries are also linked with the derivation of parent-rock of each river-basin and coastal hydrodynamics.
The disproportional higher ratio of K/I in the Yellow and abandoned Yellow River estuaries is ascribed to their sediment sources
with abundant loess component in the north-central China. The K/I decrease offshore from the Pearl River estuary is primarily
due to hydrodynamic sorting. Therefore, the S/Ch and K/I of the present study comprehensively reflect the controls of climate,
parent-rock, and sediment transport along the coast. 相似文献
997.
综合物探技术在煤系上覆薄硬岩矿区的应用初探——以山西潞安集团司马矿区为例 总被引:1,自引:0,他引:1
山西潞安集团司马矿区东高西低,西部延至长治盆地,矿区水系发育。主采3#煤层埋藏较浅,层位稳定。新生界不整合于下伏基岩之上,厚度变化较大,属典型的薄硬岩煤矿区。为准确提供矿区煤炭开采上限的地质依据,采用了综合勘探技术,其中利用三维地震勘探技术追踪新生界底面反射波及第四系"天窗"位置,利用直流电法与瞬变电磁法提供电性分层,并对其解释结果进行相互印证。勘探实例表明,三维地震勘探、电法勘探与钻探的综合运用不仅可解决薄硬岩煤矿区新生界厚度、含水层富水性及第四系缺失等问题,还可提供新生界含水层与基岩含水层之间的水力联系、制约因素等资料。 相似文献
998.
Gyesoon Park Samgyu Park Myeong-Jong Yi Hyoungrae Rim Seong-Jun Cho Jung-Ho Kim 《Environmental Earth Sciences》2010,60(5):965-974
Two-dimensional (2-D) electrical resistivity and three-dimensional (3-D) gravity explorations were undertaken to estimate
the 3-D distribution of karst cavities at the area of Yongweol-ri in Korea where ground subsidence has occurred. Although
the gravity method is a low-cost way of analyzing a 3-D continuous structure, its vertical resolving power is poor. In contrast,
the electrical resistivity method can provide a 2-D and/or 3-D subsurface structure with a much higher lateral and vertical
resolution than the gravity method. Accordingly, geostatistical methods and density information were used to enhance the 2-D
resistivity structure revealed by the electrical resistivity method into a 3-D structure. The assumptions are, first, that
each data set senses the same underlying geological structure in terms of different material properties and, secondly, that
two different material properties are correlated locally or globally throughout the entire target area. As a result, the distribution
of limestone cavities can be estimated under the assumption that they are mostly filled with groundwater and clayey soils
and have abnormally low levels of resistivity and density. The estimated distribution corresponds with the grouting, borehole
imaging and monitoring data. In this example, it can be seen that the integration analysis of 2-D electrical resistivity and
3-D gravity methods is a very powerful tool for 3-D subsurface imaging and that the method can provide enhanced imaging capabilities
for 3-D cavities. 相似文献
999.
Jianbu Wang Zhaoyang Lin Yuanqing Ma Guangbo Ren Zijun Xu Xiukai Song Yi Ma Andong Wang Yajie Zhao 《海洋学报(英文版)》2022,41(6):31-40
Spartina alterniflora as an alien invasive plant, poses a serious threat to the ecological functions of the coastal wetland of the Jiaozhou Bay. As of 2019, the distribution area of S. alterniflora in the Jiaozhou Bay has reached more than 500 hm2. For this reason, combined with field surveys, remote sensing monitoring of the invasion S.alterniflora in the Jiaozhou Bay has been carried out. To accurately identify S. alterniflora within the Jiaozhou Bay coastal wetland, we used a new m... 相似文献
1000.
The modern fishery stock assessment could be conducted by various models, such as Stock Synthesis model with high data requirement and complicated model structure, and the basic surplus production model, which fails to incorporate individual growth, maturity, and fishery selectivity, etc. In this study, the Just Another Bayesian Biomass Assessment (JABBA) Select which is relatively balanced between complex and simple models, was used to conduct stock assessment for yellowfin tuna (Thunnus albacares) in the Atlantic Ocean. Its population dynamics was evaluated, considering the influence of selectivity patterns and different catch per unit effort (CPUE) indices on the stock assessment results. The model with three joint longline standardized CPUE indices and logistic selectivity pattern performed well, without significant retrospective pattern. The results indicated that the stock is not overfished and not subject to overfishing in 2018. Sensitivity analyses indicated that stock assessment results are robust to natural mortality but sensitive to steepness of the stock-recruitment relationship and fishing selectivity. High steepness was revealed to be more appropriate for this stock, while the fishing selectivity has greater influence to the assessment results than life history parameters. Overall, JABBA-Select is suitable for the stock assessment of Atlantic yellowfin tuna with different selectivity patterns, and the assumptions of natural mortality and selectivity pattern should be improved to reduce uncertainties. 相似文献