兰州新区地理国情监测三维展示系统的设计与实现

兰州新区地理国情监测三维展示系统以兰州新区地理国情普查综合统计成果为基础,基于Skyline软件建立三维场景。在所建成的三维场景中叠加地理国情监测各类专题信息并设计展示效果,最后将三维场景封装入所开发的展示系统中,用以展示兰州新区的区位优势、地形地貌、总体规划、地理国情监测成果等内容。     

应用遥感技术进行森林资源监测方法的研究

森林资源有较强的动态性,监测技术的改进具有重要的生产意义。采用遥感技术,地理信息系统技术与森林连续清查技术相结合的方法实施森林资源监测具有极大的潜力。通过在松江河进行的研究,证明了这种方法的可行性和优越性。 文章探讨了使用新方法的关键技术环节,提供了实施监测的实际结果,指出了在我国北方国有林区推广的前景。与传统方法相比,新方法提供了图面资料,减少地面工作量50％,降低经费20％。     

PDR—2台网的群延迟

本文以PDR—2记录仪构成的小型数字化地震观测系统为基础,从理论上对该系统的群延迟进行了分析,同时还进行了实际测算,发现在这种具有不太复杂电子线路的短周期地震观测系统中,群延迟的数值也是可观的。文章分析了它的特性及从中发现的信息还谈到了有关测试方法。     

论火山喷发危险的监测研究中的CT技术的应用前景

在“九五”科技重点项目“中国若干近代火山潜在喷发危险及其监测研究”项目起动之际,作者对于火山喷发危险的监测研究中的ＣＴ技术者进行调研,本文总结了这方面的研究３方法和思路,并介绍了中国在这方面的部分成果,展望今后的研究动向。     

The mechanics of mudslides as a cyclic undrained–drained process

Data collected by monitoring suggest that the movement of mudslides essentially develops through alternating stages of undrained–drained deformation. Undrained conditions are established as a consequence of landslide mobilisation or reactivation. Every acceleration phase is followed by progressive deceleration associated with dissipation of excess pore pressure. This paper reports the results of some simple numerical analyses performed to investigate the role of pore pressure on mudslide behaviour.     

Lava effusion rate definition and measurement: a review

Measurement of effusion rate is a primary objective for studies that model lava flow and magma system dynamics, as well as for monitoring efforts during on-going eruptions. However, its exact definition remains a source of confusion, and problems occur when comparing volume flux values that are averaged over different time periods or spatial scales, or measured using different approaches. Thus our aims are to: (1) define effusion rate terminology; and (2) assess the various measurement methods and their results. We first distinguish between instantaneous effusion rate, and time-averaged discharge rate. Eruption rate is next defined as the total volume of lava emplaced since the beginning of the eruption divided by the time since the eruption began. The ultimate extension of this is mean output rate, this being the final volume of erupted lava divided by total eruption duration. Whether these values are total values, i.e. the flux feeding all flow units across the entire flow field, or local, i.e. the flux feeding a single active unit within a flow field across which many units are active, also needs to be specified. No approach is without its problems, and all can have large error (up to ∼50%). However, good agreement between diverse approaches shows that reliable estimates can be made if each approach is applied carefully and takes into account the caveats we detail here. There are three important factors to consider and state when measuring, giving or using an effusion rate. First, the time-period over which the value was averaged; second, whether the measurement applies to the entire active flow field, or a single lava flow within that field; and third, the measurement technique and its accompanying assumptions.     

基于ArcGIS的青藏高原生态地质环境遥感监测系统

青藏高原生态地质环境监测系统以ArcG IS为支撑平台,采用C/S和B/S混合模式,在空间地理基础上建立了青藏高原现代冰川雪线、河流湖泊、地质灾害、荒漠化、地质构造等多专业、多层面、多功能的生态地质环境遥感监测系统。本文重点介绍了系统功能及相关开发技术。     

Assessment of the Water and Habitat Quality of a Mediterranean River (Kalamas,Epirus, Hellas), in Accordance with the EU Water Framework Directive

In the present study, the water quality of Kalamas river (NW Greece) was evaluated using physicochemical and hydromorphological parameters and benthic macroinvertebrates. Statistical analyses (Cluster and FUZZY analyses) were performed and two biotic scores (BMWP' and HS) were used in order to classify the sites according to water quality. Kalamas river appeared to have excellent tomoderate water quality at all sampling sites except one (close to the delta area) which was ”fairly or significantly polluted”. During the low flow season water quality appeared poorer than during the high flow season. The ecological parameters (hydromorphological, chemical, and biological) used for this integrated approach are the ones proposed by the New Water Directive 2000/60 EC for an efficient surveying monitoring of running waters.     

填埋场渗滤液污染地下水问题实例分析

结合工程实例叙述了填埋场场址选择和防渗处理设施,建立针对填埋场地下水污染问题的预测模型,利用该预测模型对填埋场渗滤液污染地下水进行计算与分析,结果表明,选择合适的填埋场不仅工程措施简单,工程投资少,而且对地下水的污染甚微,能更好满足填埋要求。     

三维扫描仪协同GNSS-RTK在复杂地形测量中的应用研究

建设工程进行过程中施工现场地形复杂且呈现动态变化,施工过程中工程实体形度和施工操作对周围环境造成的影响都需要进行监控测量,建设工程施工测量是复杂地形测量的代表。本文讨论复杂地形监控测量过程中利用三维激光扫描测量的快速获取数据,获取到的据利用专业的处理软件处理后获得监控测量物体的立体成像结果,再利用全球导航卫星系统实时动态载波相位差分技术(GNSS-RTK)辅助测量监控点的空间坐标变化以及高程差。两者协同应用可以既快速又准确的进行复杂地形的监控测量。