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111.
原子荧光光度法测定土壤样品中砷的不确定度评定 总被引:1,自引:0,他引:1
通过原子荧光光度法对土壤样品中砷重复测定6次,计算实验标准差,同时对测试过程系统效应产生的不确定度分量进行评估,从而评定其不确定度。 相似文献
112.
通过对某高层建筑物的雷电风险评估,雷电风险评估方法和从雷电环境特点、风险分量和损失类型、风险评估计算等方面对某高层建筑物的雷电风险评估,得到评估建筑物的雷电风险评估综合结论,并提出了具体的防护建议. 相似文献
113.
可能最大风暴潮风险评估中各等级热带气旋设定方法 总被引:1,自引:0,他引:1
可能最大热带气旋的设定是可能最大风暴潮计算的基础,对风暴潮灾害应急疏散具有重要意义。利用1949~2011年中国气象局(CMA)西北太平洋热带气旋最佳路径数据集、美国联合台风预警中心(JTWC)以及美国国家海洋和大气管理局(NOAA)最大风速半径数据集,基于各等级热带气旋参数之间的定量关系,建立了各等级可能最大热带气旋最大风速、中心气压、最大风速半径、移动速度、移动方向等参数设定及路径合成的方法。以福建省连江县为例,按照台风、强台风及超强台风强度等级,分强度衰减和不衰减2种情况,设定3种移动方向,合成了共216场热带气旋作为可能最大风暴潮的计算输入。另外,对参数敏感性、风场参数设定、参数设定与计算量的关系、叠加天文潮以及溃堤等问题进行了讨论。 相似文献
114.
115.
Ecosystem-based marine spatial management: Review of concepts, policies, tools, and critical issues 总被引:1,自引:0,他引:1
Stelios Katsanevakis Vanessa Stelzenmüller Andy South Thomas Kirk Sørensen Peter J.S. Jones Sandy Kerr Fabio Badalamenti Christos Anagnostou Patricia Breen Guillem Chust Giovanni D’Anna Mike Duijn Tatiana Filatova Fabio Fiorentino Helena Hulsman Kate Johnson Aristomenis P. Karageorgis Ingrid Kröncke Simone Mirto Carlo Pipitone Susan Portelli Wanfei Qiu Henning Reiss Dimitris Sakellariou Maria Salomidi Luc van Hoof Vassiliki Vassilopoulou Tomás Vega Fernández Sandra Vöge Anke Weber Argyro Zenetos Remment ter Hofstede 《Ocean & Coastal Management》2011,54(11):807-820
Conventional sectoral management and piecemeal governance are considered less and less appropriate in pursuit of sustainable development. Ecosystem based marine spatial management (EB-MSM) is an approach that recognizes the full array of interactions within an ecosystem, including human uses, rather than considering single issues, species, or ecosystem services in isolation. Marine spatial planning and ocean zoning are emerging concepts that can support EB-MSM. EB-MSM is driven by high-level goals that managers aim to achieve through the implementation of measures. High-level goals and objectives need to be translated into more operational objectives before specific targets, limits and measures can be elaborated.Monitoring, evaluation and adaptation are necessary to ensure that marine management measures are both effective and efficient. Solid monitoring frameworks are the foundation of adaptive management, as they provide the necessary information to evaluate performance and the effectiveness of management actions. Marine protected areas (MPAs) - possibly set up in networks - constitute a key component in EB-MSM policies and practises and have been applied as a cornerstone in conservation of marine biodiversity, management of fish populations, development of coastal tourism, etc. Moreover, MPA experiences have provided methods and concepts (such as zoning) to a wider EB-MSM context. The assignment of values to biophysical features of the marine environment allows the direct assessment of related management choices and may assist EB-MSM.A range of monetary valuation techniques have been proposed to reduce attributes of goods and services to a single metric. However, in the marine environment such an approach is often over simplistic, and thus less reductive techniques may be necessary. Rather than producing a single metric, the results of non-monetary assessments guide policy allowing weight to be given as necessary to potential areas of conflict and consensus.Strategies to take into account climate change effects and geohazard risks in EB-MSM have been applied or proposed worldwide. EB-MSM regimes must be alert to such risks and flexible to account for changes. 相似文献
116.
关志强 《广东海洋大学学报》1997,(2)
通过模拟计算压力比、单位容积制冷量和理论循环制冷系数等性能指标,对比评价HCFC-123和CFC-11两种制冷工质。理论分析表明:HCFC-123工质性质接近于CFC-11,是当前可以接受的CFC-11的过渡性替代工质. 相似文献
117.
MONA Lisa 《《地质学报》英文版》2014,88(4):1157-1168
The site of Mansehra is located seismically in an active regime, known as the Crystalline Nappe Zone and Hazara-Kashmir Syntaxis in NW Himalayas, Pakistan. Seismic Hazard Assessment (SHA) for the site has been carried out by considering the earthquake source zones, selection of appropriate attenuation equations, near fault effects and maximum potential magnitude estimation. The Mansehra Thrust, Oghi Fault, Banna Thrust, Balakot Shear Zone, Main Boundary Thrust, Panjal Thrust, Jhelum Fault and Muzaffarabad Fault and, further to the south, the Sanghargali, Nathiagali, and Thandiani Thrusts are the most critical tectonic features within the 50 km radius of Mansehra. Using the available instrumental seismological data from 1904 to 2007, SHA has been carried out. Other reactivated critical tectonic features in the area have been investigated. Among them the Balakot-Bagh fault, with the fault length of 120 km from Balakot to Poonch, has been considered as the most critical tectonic feature on the basis of geological/structural/seismological data. The potential earthquake of maximum magnitude 7.8 has been assigned to the Balakot-Bagh fault using four regression relations. The peak ground acceleration value of 0.25 g (10% probability of exceedance for 50 years) and 0.5 g has been calculated with the help of the attenuation equation using probabilistic and deterministic approaches. 相似文献
118.
梅岭矿区勘探程度较高,积累了大量的地质资料及研究成果,此次研究,建立了梅岭矿区三维地质数据库,应用Micromine软件建立铜矿体三维模型及Fm1断层模型,并应用距离反比法对M1和M2号矿体矿块模型进行空间插值,获得相应的品位模型.通过对比不同勘探网度条件下的矿体三维模型及矿体品位、矿石储量等特征的变化,探讨了在M1和M2号矿体勘探范围内设计勘探网度的合理性. 相似文献
119.
Qin-Bo Cheng Christian Reinhardt-Imjela Xi Chen Achim Schulte Xiang Ji Fu-Lin Li 《水文科学杂志》2013,58(8):1460-1476
ABSTRACTA new physics-based rainfall–runoff method of the Soil and Water Assessment Tool (SWAT) was developed, which integrates a water balance (WB) approach with the variable source area (WB-VSA). This approach was further compared with four methods—soil-water-dependent curve number (CN-Soil), evaporation-dependent curve number (CN-ET), Green and Ampt equation (G&A) and WB—in a monsoonal watershed, Eastern China. The regional sensitivity analysis shows that volumetric efficiency coefficient (VE) with river discharges is sensitive to the most parameters of all approaches. The results of model calibration against VE demonstrate that WB-VSA is the most accurate owing to its reflection of the spatial variation of runoff generation as affected by topography and soil properties. Other methods can also mimic baseflow well, but the G&A and CN-ET simulate floods much worse than the saturation excess runoff approaches (WB-VSA, WB and CN-Soil). Meanwhile, CN-Soil as an empirical method fails to simulate groundwater levels. By contrast, WB-VSA captures them best.
Editor M.C. Acreman; Associate editor S. Kanae 相似文献
120.