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991.
Watershed water quality models are increasingly used in management. However, simulations by such complex models often involve significant uncertainty, especially those for non-conventional pollutants which are often poorly monitored. This study first proposed an integrated framework for watershed water quality modeling. Within this framework, Probabilistic Collocation Method (PCM) was then applied to a WARMF model of diazinon pollution to assess the modeling uncertainty. Based on PCM, a global sensitivity analysis method named PCM-VD (VD stands for variance decomposition) was also developed, which quantifies variance contribution of all uncertain parameters. The study results validated the applicability of PCM and PCM-VD to the WARMF model. The PCM-based approach is much more efficient, regarding computational time, than conventional Monte Carlo methods. It has also been demonstrated that analysis using the PCM-based approach could provide insights into data collection, model structure improvement and management practices. It was concluded that the PCM-based approach could play an important role in watershed water quality modeling, as an alternative to conventional Monte Carlo methods to account for parametric uncertainty and uncertainty propagation. 相似文献
992.
B. Flemisch M. DarcisK. Erbertseder B. FaigleA. Lauser K. MosthafS. Müthing P. NuskeA. Tatomir M. WolffR. Helmig 《Advances in water resources》2011,34(9):1102-1112
DuMux is a free and open-source simulator for flow and transport processes in porous media, based on the Distributed and Unified Numerics Environment (DUNE). Its main intention is to provide a sustainable and consistent framework for the implementation and application of model concepts, constitutive relations, discretizations, and solvers. The paper provides an overview of DuMux with the focus on software-related aspects. Selected examples highlight the multi-scale and the parallel capabilities. 相似文献
993.
Electrical Resistivity Tomography (ERT) can provide images of subsurface electrical structure between two boreholes. Data quality control is a key issue before ERT inversion. However, there is no effective data quality control method on an ERT survey. In this paper, a method called common current gather for a bipole–bipole array (CCGbb) was proposed to check ERT data quality in a rapid way. Synthetic models were conducted to compare the response difference between pole–pole array and bipole–bipole array. A field work at granite area was tested to verify the applicability of the proposed CCGbb method. From the results of this study, we suggested that conducting CCGbb before ERT inversion and a cross-borehole tracer test for both field data quality control and possible water conducting fractures (WCFs) delineation. 相似文献
994.
云南地区背景噪声互相关函数中体波信号来源初探 总被引:3,自引:0,他引:3
利用云南地区43个宽频带地震台站记录的2008~2010年垂直分量数据,计算了台站对间的互相关函数并得到了5~40 s周期的瑞利面波信号。研究发现在5~10 s周期范围内,瑞利面波信号之前存在很强的前驱信号,该信号能量优势频段为0.1~0.2 Hz,其到时接近噪声互相关函数零点,视速度约为30 km/s。该信号到时随季节存在正负交替变化,进一步的质点分析表明该信号为出射角较小的P波信号。参考已有的研究,认为远场地脉动噪声源中的P波信号穿过地球深部到达云南地区,形成了噪声互相关函数中视速度较高的体波信号,并且相关的噪声源位置在冬季和夏季分别位于北太平洋和南印度洋,具有明显的季节性空间变化。 相似文献
995.
Kateline Young 《地震学报(英文版)》2011,(2):199-206
The 2009 M W 7.8 Fiordland (New Zealand) earthquake is the largest to have occurred in New Zealand since the 1931 M W 7.8 Hawke’s Bay earthquake, 1 000 km to the northwest. In this paper two tracks of ALOS PALSAR interferograms (one ascending and one descending) are used to determine fault geometry and slip distribution of this large earthquake. Modeling the event as dislocation in an elastic half-space suggests that the earthquake resulted from slip on a SSW-NNE orientated thrust fault that is associated w... 相似文献
996.
997.
利用宁夏及邻区的数字测震资料,选取2009年5月至2010年10月间的31个M2.7-ML4.9地震事件的波形记录,以Brune提出的震源谱为平方模型基础,通过消除观测谱中的几何扩散、非弹性衰减、场地响应、仪器响应等影响因素,得到这些地震的震源谱,根据Brune的圆盘震源模型计算并研究地震矩、矩震级、地震应力降、震源尺... 相似文献
998.
对湟源地震台周边各种因素所致的地震记录干扰情况进行了分析,认为干扰源主要有采石场爆破、灌溉水渠、小河、车辆干扰及各种天气及固有干扰等。根据这些干扰源的频谱特性,采用MATLAB语言,设计、编制了不同类型的滤波器,在震相识别上发挥了很大作用。 相似文献
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1000.
对近年来有关生物质燃烧排放的颗粒物中有机化合物和有机示踪物的研究进展进行了综述,分析了各国学者根据有机示踪物研究城市大气颗粒物中生物质燃烧和其他排放源对空气污染的贡献,对以后的相关研究具有借鉴意义. 相似文献