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排序方式: 共有637条查询结果,搜索用时 140 毫秒
521.
522.
深基坑施工安全监测的探讨 总被引:1,自引:0,他引:1
文章从明确深基坑施工安全监测的关键出发,确定了监测内容和相关极限报警值,用工程实例进行了阐述。 相似文献
523.
伽师地震与区域断层活动研究 总被引:1,自引:1,他引:0
利用GPS、连续倾斜和地震活动性资料分析了伽师地区构造活动的特点和伽师强震群的动力背景,结果表明:在印度洋板块的挤压下,塔里木盆地的右旋腑冲运动是造成南天山区地震活动的主要原因;1996年3月19日伽师阿图什6.7级地震,强烈地影响了该地区块体由向西南倾斜转向北向倾斜,并可能成为诱伽师地区强震群活动的主要动力因素,利用1998年和1999年对该地区GPS测量的结果,给出了该地区断层活动的水平。 相似文献
524.
The loss of natural habitats and the loss of biological diversity is a global problem affecting all ecosystems including agricultural landscapes. Indicators of biodiversity can provide standardized measures that make it easier to compare and communicate changes to an ecosystem. In agricultural landscapes the amount and variety of available habitat is directly correlated with biodiversity levels. Linear woody features (LWF), including hedgerows, windbreaks, shelterbelts as well as woody shrubs along fields, roads and watercourses, play a vital role in supporting biodiversity as well as serving a wide variety of other purposes in the ecosystem. Earth observation can be used to quantify and monitor LWF across the landscape. While individual features can be manually mapped, this research focused on the development of methods using line intersect sampling (LIS) for estimating LWF as an indicator of habitat availability in agricultural landscapes. The methods are accurate, efficient, repeatable and provide robust results. Methods were tested over 9.5 Mha of agricultural landscape in the Canadian Mixedwood Plains ecozone. Approximately 97,000 km of LWF were estimated across this landscape with results useable both at a regional reporting scale, as well as mapped across space for use in wildlife habitat modelling or other landscape management research. The LIS approach developed here could be employed at a variety of scales in particular for large regions and could be adapted for use as a national scale indicator of habitat availability in heavily disturbed agricultural landscape. 相似文献
525.
Sinem Yavuz Roman Pevzner Sofya Popik Konstantin Tertyshnikov Todd Wood Michelle C. Robertson Julia Correa Barry Freifeld 《Geophysical Prospecting》2022,70(1):108-120
Time-lapse seismic is one of the main methods for monitoring changes in reservoir conditions caused by production or injection of fluids. One approach to time-lapse seismic is through permanent reservoir monitoring, whereby seismic sources and/or receivers are permanently deployed. Permanent reservoir monitoring can offer a more cost-effective and environmentally friendly solution than traditional campaign-based surveys that rely on temporarily deployed equipment while facilitating more frequent measurements. At the CO2CRC Otway Project, surface orbital vibrators were coupled to a buried geophone array to form a permanent reservoir monitoring system. These are fixed position seismic sources that provide both P and S waves using induction motor-driven eccentric masses. After an initial injection of CO2 in February 2016, five months of continuous seismic data were acquired, and reflection imaging was used to assess the system performance. Analysis of the data showed the effects of weather variations on the near-surface conditions and the sweep signatures of surface orbital vibrators. Data processing flows of the continuous data was adapted from Vibroseis four-dimensional data processing flows. Ground roll proved a significant challenge to data processing. In addition, variations in the surface wave pattern were linked to major rainfall events. For the appraisal of surface orbital vibrators in imaging, a Vibroseis four-dimensional monitor survey data with similar geometry was also processed. Surface orbital vibrators are observed to be reliable sources with a potential to provide a repeatable signal, especially if the ground roll should fall outside the target window of interest. To guide future permanent reservoir monitoring applications, a repeatability analysis was performed for the various key data processing steps. 相似文献
526.
北京地区地质遗迹现状与保护对策研究 总被引:1,自引:0,他引:1
地质遗迹是珍贵不可再生的自然遗产,北京地区拥有丰富的地质遗迹资源,部分地质遗迹因工程建设、矿产资源开发等原因正在遭受破坏或已完全破坏,现状堪忧,从保护地质遗迹资源、推进生态文明建设、落实国家有关办法规定、落实有关规划和示范意义等方面,建议开展地质遗迹监测工作。通过分析认为,北京地区地质遗迹监测对象明确;目前监测技术成熟,包括人工巡查监测、遥感监测和物联网监测等;信息系统建立有基础,有大批从事地质遗迹相关工作的专业技术人才;资金落实有保障,地质遗迹监测主责单位和服务对象明确,监测技术的应用将有利于北京地区地质遗迹的保护研究。 相似文献
527.
阐述了建设重庆市气候灾害监测预警系统的意义,介绍了系统设计方案、系统结构与功能、气候灾害指标以及在试运行中的监测效果,最后描述系统后期的完善设计思路及欲达的目标。 相似文献
528.
本文就浙江省电子监察数据采集系统(以浙江省建设用地审批管理信息系统为例)的应用和数据采集进行了探索和研究,为信息化目前面临的主要整合系统、建立一体化运营平台工作提供思路和技术路线。 相似文献
529.
基于C/S与B/S混合体系结构的林业管护经营监控系统的设计 总被引:1,自引:0,他引:1
对C/S,B/S两种软件体系结构进行了分析比较,论述了林业管护经营监控系统是一个大型的、复杂的监控系统,针对不同的用户,采取合理的软件体系结构设计,将会使该系统具有更好的应用前景.提出了基于C/S与B/S混合体系的林业管护经营监控系统的设计框架,包括其实现的主要功能、体系结构、安全策略、数据备份与恢复等关键技术. 相似文献
530.
M. Tataranni F. Maltagliati A. Floris A. Castelli C. Lardicci 《Marine environmental research》2009,67(4-5):219-229
The effects of taxonomic resolution on the variance estimates of macrobenthic assemblages were studied at four spatial scales in a Mediterranean coastal lagoon. The assemblages exhibited significant differences at all the investigated scales; however, spatial variability was mainly associated with the smallest and the largest scales. The decrease of taxonomic resolution (from species to family) was not related to a decrease of the overall variability and similar estimates of variance components were obtained using species and family resolution levels. The ordination models derived from species and family abundances were very similar both in terms of location and dispersion effect, while further aggregation to the class level began to alter the observed spatial patterns. In future studies aimed at assessing changes in the lagoon, resources derived from the cost reductions achieved using family level could be employed to plan more frequent surveys and/or to adopt complex spatial sampling designs with a high number of replicates. 相似文献