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71.
中子活化分析在公路交通燧洞水文地质调查中的应用   总被引:1,自引:0,他引:1  
利用中子活化测试结果 ,对岩石及泉水干涸残余物中常量及微量元素的进行分析对比 ,以了解深层岩体有关的地质与水文地质信息  相似文献   
72.
Robustness analysis of geodetic horizontal networks   总被引:2,自引:1,他引:2  
  相似文献   
73.
目的:对颅脑转移瘤的来源、分布部位及瘤周水肿三者关系进行分析与探讨。方法:将54例颅脑转移瘤检出93个病灶,行平扫及增强扫描。将颅脑分为三个区:1区指大脑半球皮髓质交界区;2区指大脑半球;3区指小脑、脑干。水肿分为四个级别:0度无水肿;1度ETR<=1;2度1相似文献   
74.
方宏芳 《华南地震》2001,21(4):44-49
运用最大树法模糊聚类分析,将台湾地区1936年至1989年间的35个地震事件分成了三类6型,并运用聚类结果对1990年至2000年的11个地震事件进行检验,得出了比较合理的检验结果,最后用聚类结果对台湾地区2001年的地震趋势进行了预测,得出了与其它手段一致的预报结果.  相似文献   
75.
北秦岭地带断裂活动性氡气测试成果分析评价   总被引:6,自引:4,他引:6  
采用断层气体测试方法, 对北秦岭地带主要断裂及其活动性进行了测试, 首次提出了该区断裂活动性测氡成果判别的相对标准。进而对区内典型的氡气测试成果剖面作了解释分析, 并判别了断裂 (带)的相对活动强弱与活动水平等有关断裂活动性问题。最后, 简要地探讨了在北秦岭地区未来可持续发展中断裂 (带)对其模式及格局的影响。  相似文献   
76.
In order to realize sustainable development of the arid area of Northwest China, rational water resources exploitation and optimization are primary prerequisites. Based on the essential principle of sustainable development, this paper puts forward a general idea on water resources optimization and eco-environmental protection in Qaidam Basin, and identifies the competitive multiple targets of water resources optimization. By some qualitative methods such as Input-output Model & AHP Model and some quantitative methods such as System Dynamics Model & Produce Function Model, some standard plans of water resources optimization come into being. According to the Multiple Targets Decision by the Closest Value Model, the best plan of water resources optimization, eco-environmental protection and sustainable development in Qaidam Basin is finally decided.  相似文献   
77.
During the development of Qaidam Basin, which is an arid area in Northwest China, rational water resources utilization and optimization are primal prerequisites, and the main restrictive factors include the following facts: scarcy water resources are non-substitutional and uneven distributed in time and space. Based on the essential principle of sustainable development, this paper adopts Multiple Targets Decision by the Closest Value Model, and succeeds in getting the best plan, which can o…  相似文献   
78.
计算机仿真模型的灵敏度分析,是仿真建模中的重要研究内容,对实际系统的建立和优化具有重要意义。本文主要研究了在用蒙特卡洛方法仿真随机系统时,其仿真模型(输出)的灵敏度(导数、梯度、Hessian矩阵等),对系统性能函数和灵敏度的参数估计进行了探讨,并结合实际应用系统,对结论进行了分析比较。  相似文献   
79.
Aseismio fault slip and block deformation in North China   总被引:1,自引:0,他引:1  
In North China, the tectonic fault-block system enables us to use the Discontinuous Deformation Analysis (DDA) method to simulate the long-term cross-fault survey and other geodetic data related to aseismic tectonic deformation. By the simulation we have found that: (1) Slips on faults with different orientation are generally in agreement with the ENE-WSW tectonic stress field, but the slip pattern of faulting can vary from nearly orthogonal, to pure shear along the strike of the faults, this pattern cannot be explained by simple geometric relation between the strike of the fault and the direction of the tectonic shortening. This phenomenon has been observed at many sites of cross-fault geodetic surveys, and might be caused by the interactions between different blocks and faults. (2) According to the DDA model, if the average aseismic slip rate along major active faults is at the order of several tenths of millimeter per year as observed by the cross-fault geodetic surveys, the typical strain rate inside a block is at the order of 10–8 year–1 or less, so that the rate of 10–6 year–1, as reported by observations in smaller areas, cannot be the representative deformation rate in this region. (3) Between the slips caused by regional compression and block rotation, there is a possibility that the sense of slip caused by rigid body rotation in two adjacent blocks is opposite to the slip caused by the tectonic compression. But the magnitude of slip resulting from the tectonic compression is much larger than that due to the block rotation. Thus, in general, the slip pattern on faults as a whole agrees with the sense of tectonic compression in this region. That is to say, the slip caused by regional compression dominates the entire slip budget. (4) Based on (3), some observed slips in contradiction to ENE tectonic stress field may be caused by more localized sources, and have no tectonic significance.  相似文献   
80.
Monitoring and evaluation of groundwater quality in drinking water protectorates is of particular interest if the uncontrolled entry of pollutants, for example by infiltrating river water, cannot be excluded. A fluorescence spectroscopic method is presented as possible alternative to the conventional expensive hydrochemical investigations. This method uses the information yielded by synchronous fluorescence spectra. After a Fourier transformation of the original spectra and a following discriminant analysis, the samples can be classified in different groups corresponding to the different types of groundwater. The method was tested in the drinking water protectorate of a waterworks of a German metropolis (Halle, Sachsen-Anhalt). We found a prediction rate of about 90% in the investigated case.  相似文献   
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