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991.
通过对锦屏一级水电站左岸抗力体五层洞室岩体结构特征详细调查,采用水电围岩分类的方法对抗力体洞室进行围岩分类。分类结果表明:抗力体洞室围岩以Ⅲ2类围岩居多,占了50%左右,其次为Ⅳ类,占36%左右,Ⅲ1和Ⅴ类围岩所占比例较少。通过对洞室施工开挖失稳破坏现象的调查研究,分析了洞室失稳破坏的机制及破坏形式,认为围岩主要的破坏形式为弱面控制型的块体滑移塌落。对洞室监测资料的分析结果表明,在目前的支护条件下,总体监测未见异常,整体上基础处理洞室监测状态稳定。但F5、F42-9断层及煌斑岩脉等软弱部位应力及变形缓慢增加,需要加强监测。最后根据分析结果提出了建议。  相似文献   
992.
介绍了基于无线通讯网络的GPS多天线监测系统的构成情况,包括系统设计、数据传输与管理、数据处理、数据质量分析和控制等。在公路边坡变形监测中的实际应用结果表明,该系统1 h测量精度已达到3.0 mm左右,既能自动连续地对滑坡变形进行监测,又能大幅度降低整个监测系统的费用,是滑坡等地质灾害变形监测的理想技术之一。  相似文献   
993.
Brillouin optical time-domain reflectometer (BOTDR), a newly developed distributed fiber optic sensing technique, has been proved to be a very suitable and useful technique for monitoring and early warning of structural engineering by laboratory tests and practical projects due to its unique functions, such as distributing, long distance, anti-electromagnetic interference, waterproof, etc. However, its application to geotechnical engineering, especially soil-slope engineering, has been less carried out due to the complexity of the characteristics of geotechnical materials in the field. In this paper, BOTDR technique is applied to monitor the deformation of a laboratory soil-slope model in small scale in order to test the feasibility and early-warning characteristics of this technique with monitoring the deformation of soil slope. Different types of optical fibers are planted directly in the soil-slope model or bonded to geotextiles and geogrids that are planted in the fillings of the test model. Strain measurements of the model slope under various loads are obtained by BOTDR. By data processing and analysis, the abnormal strains can be obtained distributively, and the position of the abnormal strains can be located as well. The results show much valuable information for applications of BOTDR technique into soil-slope engineering. The test proves that the BOTDR technique can be used to ensure the stability of artificial soil slope and is useful for monitoring and early warning of the artificial soil-slope engineering.  相似文献   
994.
近20年来,高光谱遥感技术(Hyperspectral Remote Sensing)发展迅速,已成为遥感技术的前沿,而矿产资源评价与矿山环境监测是高光谱遥感应用中最成功的领域。高光谱遥感技术具有分辨率高的特点,通过对矿物种类、丰度和成分的识别,特别是对与成矿作用、矿山污染源密切相关的蚀变矿物的识别,可以有效地圈定热液矿化蚀变带,定量或半定量地估计相对蚀变强度和蚀变矿物含量,从而进行岩石矿物的分类和填图,并为矿产资源评价与矿山环境监测提供靶区,指导进一步找矿勘探和环境监测工作的开展。介绍了高光谱遥感技术在矿产资源评价与矿山环境监测中的应用原理和成像光谱学的逐步完善,并详细列举了高光谱遥感技术在斑岩铜矿、热液型金矿、地浸砂岩型铀矿、油气、金刚石等矿种的找矿方面,以及在矿山废弃物中生成酸和缓冲酸分布的监测等方面的具体案例,以期为中国矿产资源评价与矿山环境监测中高光谱遥感技术的应用提供借鉴。  相似文献   
995.
应用GPS定位技术进行城市或区域地壳变形监测,研究了GPS监测的数据处理和精度分析的理论和方法.使用高精度的定位分析软件GAMIT,对某城市地壳变形监测网的试验观测数据进行数据处理,并对解算得到的基线向量和坐标分别进行精度分析,结果表明:在100km范围内,GPS基线重复率在平面上比例误差可以达到10-8,垂直方向比例误差可以达到10-7;GPS监测点的三维坐标重复率精度可达到3mm左右,能满足城市或区域地壳变形监测的精度要求.  相似文献   
996.
为了改变以往土地管理部门对土地管理的传统方式,节省在常规管理中耗费的大量人力和物力,遥感技术作为新兴发展的科学技术,已应用于动态监测土地利用的变化。本文将具体论述如何利用微波遥感技术监测土地利用的动态变化。  相似文献   
997.
土地利用动态遥感监测数据库标准探讨   总被引:3,自引:1,他引:2  
马晶  曹银璇  燕琴 《测绘科学》2005,30(5):100-101
为了将土地利用动态遥感监测技术和成果进一步普及和应用,规范土地利用动态遥感监测数据库建设,依据国土资源信息化标准建设的总体部署和要求,参考相关标准和规程,结合土地利用动态遥感监测业务特点,制定了土地利用动态遥感监测数据库标准草案。  相似文献   
998.
Concurrent water data were collected by the U.S. Geological Survey, the U.S. Corps of Army Engineers, and the Maryland Department of Health and Mental Hygiene at the same site in order to describe present conditions and predict future environmental change in the Georges Creek basin in western Maryland. Evaluation of the data sets reveals measurement errors and weaknesses in sample design so that published complications contain significant errors. Unless these errors can be identified, policy based on such information may have unfortunate results.  相似文献   
999.
We surveyed small-scale farmers in the Kenyan Rift Valley province (Narok and Nakuru districts) to describe constraints to, and changes in, livestock production and to assess the extent to which farmers have adopted new technologies promoted by extension services. In the arid areas of southern Narok, farmers' main constraints were drought and disease. Farmers in Nakuru district, situated in the fertile highlands of the Rift Valley, were also affected by disease but also lacked markets and capital. Although 83% of the farmers had regular contact with extension services that provided advice on new technologies and livestock production innovations, only about half of the respondents implemented the proposed changes. Many of those who did change (38%) improved pasture/nutrition/manure management and relatively few (16%) improved their animal breeding practices. Results of a multinomial logit model revealed that, apart from the significant differences between the two districts, the nature of the advice and the expected outcomes had the strongest influence on the probability of successfully implementing changes to livestock production. The results further suggest that adoption of new technologies is limited by lack of knowledge, inadequate support and a failure to target local needs and conditions and empower livestock keepers.  相似文献   
1000.
When establishing environmental monitoring programmes, it crucial to make reliable cost estimates, especially where a field survey is involved. This paper presents a methodology for creating a spatial measure of a field survey effort (SE). A set of relevant variables affecting a SE (e.g. areas with rough terrain, or distant from the main road network) was classified using fuzzy sets and then combined to produce spatially explicit effort indicators, which were integrated to a single measure using an analytic hierarchy process (AHP). To evaluate this approach and identify the limits for its application, three spatially nested case studies were used to test the spatial expression of SE and the scalable capacity of the method itself. The presented methodology could cope with variations in the scale and data resolution, retrieving a coherent estimate of SE across the different case studies. The presented methodology is therefore useful for (i) testing the network designs for sampling bias related to SE, (ii) comparing alternative sampling designs, (iii) assessing the sampling costs and (iv) supporting the human and logistical resource management.  相似文献   
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