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153.
城市边缘区景观变化与人为影响的空间分异研究 总被引:38,自引:5,他引:38
利用1988、1993、1998年的遥感影像,应用最大似然法和概率松弛法对马山景观组分进行了测量,在此基础上,对分类结果进行比较求得研究区景观变化的转移短也阵,分析了人为改造活动与景观组分之间的对应关系和空间变化过程,马山区已经从1988年的传统农业景观转化为1998年的城郊混合景观,人口、经济、产业结构均发生了巨大变化,借助人为影响指数,利用网格采样和地统计学分析,研究了马山1988-1998年间景观的人为开发利用活动,揭示人为活动的空间变异强度分布及景观转变过程的社会驱动力。 相似文献
154.
山东数字遥测地震台网地震监测能力评估 总被引:3,自引:0,他引:3
根据地震仪器的性能对山东数字遥测地震台网的监测能力进行评估,并利用2000年3-10月地震资料进行了检验。其结果为:山东地区12%的面积监测能力为ML≥2.0级,山东中部及渤海、黄河沿海地区监测能力为ML≥2.5级,渤海、黄海近海地区的监测能力为ML≥3.0级。最后指出台网布局的疏密程度、观测条件及台基条件的优劣等是影响台网监控能力的重要因素。 相似文献
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156.
本文以赤水油气遥感为例,说明油气直接探测的意义,选择TM数字磁带资料作为提取油气遥感信息源的原因,经计算机图象处理,将直接提取出的遥感信息分类,排除油气遥感无用信息,保留其有用信息,图出有可能的天然气远景区,为进一步油气勘探提供科学依据。 相似文献
157.
通过镇江市邮电通信指挥中心大楼深基坑工程的设计与施工,全面介绍了组合钢支撑在深基坑支护工程应用中的设计、施工方法及支撑效果.实践证明,组合钢支撑是一种施工方法简单、施工速度快、对周边环境影响小、安全可靠的支撑形式,具有较强的市场竞争能力及良好的推广应用前景. 相似文献
158.
This paper describes a GPR study carried out with the aim of evaluating deterioration of concrete floors in a textile factory. In the past, production process waste was spilt onto the floor of the factory. A slow but continuous action from this waste on the concrete caused a significant variation in its porosity that can be detected by studying changes in the GPR reflected pulse. A simple synthetic model was developed in order to obtain information about how the response of the GPR antenna pulse is affected by changes in the porosity of concrete. It should also be taken into account the different conditions of the factory floor at the time of testing, as it had been isolated from the action of waste for many years. The heterogeneous conditions of the floor and the simplicity of the model used did not allow for an accurate estimate of the porosity; however, it was possible to map degraded areas of the floor in relationship to changes in the reflected signal. Core samples taken showed that some areas had concrete porosity of 15% and up to 25%, which is closer to that of sand than to concrete. 相似文献
159.
Protection of groundwater already is and will also be in the future, a particularly important environmental, socio-economic, social welfare and political task. The fact that the costs of preventive measures are 10–20 times lower than the funds needed to clean up and revitalize polluted aquifers, as well as the fact that the area to be occupied with transport communications and other infrastructure facilities will aggravate protection, both call for an urgent introduction of modern methods of monitoring and preserving all the existing and potential groundwater resources. The basic principle of groundwater protection against pollution means constant control and preventive measures of protection, namely prevention of incidental and other kinds of pollution. The very construction of communications and all accompanying facilities changes and degrades the existent natural geological environment, and when in use they may become structures in whose immediate surrounds surface and ground waters may be polluted by the toxic and waste substances transported. The experience gained through the following activities: the ‘pilot model’ for groundwater monitoring in the zone of Makis, the investigations and monitoring of critical sites polluted with xylene (CIP, Belgrade, 1994/95), and information on the latest achievements in this field in the world (obtained while working on the study of methodology of hydrogeological investigations needed for groundwater quality monitoring system — Jaroslav Cerni Institute for the Development of Water Resources, Belgrade, 1998), stresses a necessity to obligatory design and construct operational systems for groundwater quality monitoring, particularly in the zones of infrastructure facilities (roads, railway, gas pipelines, oil pipelines), which can be considered as potential linear polluters. In that light, this paper is a contribution to developing hydrogeological investigation methodology for designing and operating a monitoring system in the zones of roads, and its legal and practical incorporation in the technical documents of each project. Besides, an emphasis is put on multidisciplinary approach to system implementation, its full automation, rational management, and effective and optimal measures for groundwater protection. 相似文献
160.
应用精密水准测量方法,于1993年在温泉区取得三个周期的观测成果,结合以往资料进行综合分析,得出初步结论。并为福州市地下热水开采的控制、预防及减轻因沉降产生的地灾害方面提出有益的建议。 相似文献