如何在湖北省地震网络系统中架构VPDN平台   总被引：1，自引：1，他引：0  

刘可  张亦梅  特木其勒 《大地测量与地球动力学》2010,30(Z1)

湖北省地震系统约有100个站点需要利用无线网络系统进行信息传输,前期是利用自建的VPN网络,其传输速度受互联网的影响较大,传输速度较慢,甚至出现不能对仪器进行实时监控、数据不能按时收取、无法按时向国家台网中心报送数据的情况。而目前湖北省地震网络系统业务的拓展,需要进一步完善覆盖全省的数据传输网络,用于承载前兆无人职守系统、流动测震系统和移动办公系统。鉴于上述情况,湖北省地震信息网络部门通过分析各分支点所处的地理位置及数据传输的要求,最终使用中国电信的无线VPDN业务,组建湖北省地震数据监测VPDN网络系统。从而满足了数据传输的安全性、观测数据上报的安全性和地震分析预报的及时性要求。  相似文献   

Modeling dynamic assessment of ecosystem services based on remote sensing technology: A sampling of the Gansu grassland ecosystem     

Jian Wang  ZhengHua Chen 《寒旱区科学》2010,2(6):0514-0521

The ecosystem is important because it is the life sustaining system for human survival.Three ecosystem characteristics are:regional particularities,ecosystem complexity and conventional cultural particularities.This paper develops a remote sensing based dynamic model to assess grassland ecosystem service values involving multidisciplinary knowledge.The ecological value of grassland ecosystems is focused on using a remote sensing technique in the model,and setting up the framework for a dynamic assessing model.The grassland ecological services condition and value in 1985 is used as the benchmark.The dynamic model has two adjusting indicators:biomass and price index.The biomass is simulated using the CASA(Carnegie-Ames-Stanford Approach) model.The price index was obtained from statistics data published by the statistical bureau.Results show that the grassland ecosystem value in Gansu Province was 28.36 billion Chinese Yuan in 1985,140.37 billion in 1999 and 130.86 billion in 2002.  相似文献   

草原生态系统生态补偿机制研究:中德案例研究比较(英文)     

Sandra UTHES  ;李芬  ;甄霖  ;曹晓昌 《资源与生态学报(英文版)》2010,(4):319-330

目前,草地生态系统退化成为全球关注的问题。生态补偿机制(PES)是为了草地生态系统的恢复/保护,采取补贴或支付费用的方式,改变使用者资源利用方式的制度安排。科学、合理的生态补偿制度需要全面地考虑可能出现的风险和挑战:如环境效益的滞后性,不可预见的监督、管理成本和社会经济目标(足额补偿标准、公平)的实现。本文的目标是通过中德两国生态补偿措施的对比(选取中国内蒙古锡林郭勒盟,德国勃兰登堡州为案例区域进行研究),为今后中德两国的生态补偿理论和实践提供依据。研究着重以下四个方面进行分析:中德两国生态补偿的实施框架,目标人群,实施效果评估等。研究结果表明,由于缺乏有效的激励机制,农户作为最基层的执行单位和实施者,其参与的主动性不够,中德两国生态补偿措施实施的成效有待提高。基于研究结果,提出了今后生态补偿项目设计中,中国应侧重于项目实施的监控和管理制度;而德国应在空间目标规划和具体管理措施和方式等方面进行完善。  相似文献   

MODIS影像的局地云量信息元数据提取算法与应用     

钟洪麟  施润和  曲培青  张慧芳  高炜 《地球信息科学学报》2010,12(4):587-592

云对于光学遥感影像质量及其反演地表参数精度有着重要影响,且其作为时空多变要素之一,在一定程度上制约了光学遥感影像的应用。对于具有2 330km的大扫描幅宽MODIS影像而言,现有的元数据标准仅能反映影像的总体云量,而无法反映云的空间分布状况,限制了MODIS数据的局地研究和应用。本文在现有遥感影像元数据标准的基础上,提出了新的元数据项--局地云量,用于反映云在条带影像中的空间分布状况,并实现在MODIS二级云掩膜条带产品(MOD35)中针对特定区域的局地云量信息提取算法。经验证,本算法能较快速和准确地提取省级行政区的局地云量信息,并可根据用户的需求进一步推广到任意指定的多边形区域,为MODIS数据在局地研究和应用提供了便利。  相似文献   

基于中分辨率成像光谱仪数据的洋面云检测新方法的研究   总被引：1，自引：0，他引：1  

郭金伟  许丽生  邓小波  丁继烈  刘海磊 《成都信息工程学院学报》2010,25(3):252-255

提出了一种利用中分辨率成像光谱仪热红外窗区通道数据进行云、晴空分离的新方法。该云检测算法从热红外窗区通道亮温出发,并结合水汽廓线,运用水汽规度法计算规度因子的值,利用规度因子的数值状态实现分离云和晴空,从而达到云检测的目的。经过大量的实验,并将结果与中分辨率成像光谱仪官方云检测产品作对比分析,结果表明准确率为91％,算法具有可行性。  相似文献   

基于语义描述的制造业Web服务合成研究     

卢健  刁雅静  王志英 《成都信息工程学院学报》2010,25(2):162-166

在因特网环境下,如何对服务描述是基于web服务的应用集成的关键问题之一。Web服务合成技术为这一问题提供了很好的解决方案。以基于语义的web服务合成理论为基础,在分析制造业信息资源特点的基础之上,以库存管理领域为应用实例,选取面向服务的网络本体语言提出了制造业web服务合成语义描述的一种方法。  相似文献   

Torsionally coupled dynamic performance analysis of asymmetric offshore platforms subjected to wave and earthquake loadings     

Xiaoyu He  Hongnan Li 《地震工程与工程振动(英文版)》2010,9(2):247-258

The dynamic equations of motion of asymmetric offshore platforms under three different environmental conditions:seismic action,wave action and their combination are established in this paper. In establishing these motion equations,three typical eccentricity types including mass eccentricity,rigidity eccentricity and their combination were considered,as are eccentricities that occur un-idirectionally and bi-directionally. The effects of the eccentricity type,the dynamic characteristics and the environmental conditions on the torsional coupling response of platforms are investigated and compared. An effort has also been made to analyze the inffluence of accidental eccentricity on asymmetric platforms with different eccentricity in two horizontally orthogonal directions. The results are given in terms of non-dimensional parameters,accounting for the uncoupled torsional to lateral frequency ratio. Numerical results reveal that the eccentricity type has a great inffluence on the torsionally coupled response under different environmental conditions. Therefore,it is necessary to consider the combination of earthquake and wave action in the seismic response analysis of some offshore platforms.  相似文献   

新疆西克尔地区下奥陶统鹰山组岩溶分带性研究   总被引：1，自引：0，他引：1  

冯海霞  李树新  陈冬梅  和虎  周彩虹 《现代地质》2010,24(6):1065-1071

塔里木盆地岩溶缝洞型储层作为重要的油气储层备受关注,而目前预测此类型储层的方法较有限。在新疆伽什县西克尔野外露头区地表岩溶现象丰富,志留系地层以填平补齐的方式充填在一系列的溶沟和溶槽中,部分洼地中还有志留系地层残留,表明该区发育加里东中期岩溶。在本区岩溶古地貌的基础上,基于排泄基准面的分析,划分出3级岩溶台面并对应发育3期岩溶。据现代地貌学和岩溶学理论,按照水动力条件的不同并结合本区岩溶发育特征,运用岩溶旋回的观点将第二期岩溶剖面分为表层岩溶带、垂直渗滤带和水平潜流带,认识到西克尔地区古岩溶地下水发育规律及洞穴发育程度。构造运动是垂向岩溶分带性的主控因素;因此,在大的构造背景的前提下,可以有效地预测巴楚地区的缝洞型储层。  相似文献   

Root properties of vegetation communities and their impact on the erosion resistance of river dikes   总被引：1，自引：0，他引：1       下载免费PDF全文

Wouter Vannoppen  Jean Poesen  Patrik Peeters  Sarah De Baets  Bart Vandevoorde 《地球表面变化过程与地形》2016,41(14):2038-2046

Predicted climate change and the associated sea level rise poses an increased threat of flooding due to wave overtopping events at sea and river dikes. To safeguard the land from flooding it is important to keep the soil erosion resistance at the dikes high. As plant roots can be very effective in reducing soil erosion rates by concentrated flow, the main goal of this study is to explore the variability in root system characteristics of five dike vegetation communities along the Scheldt River (Belgium) and to assess their effectiveness in controlling soil erosion rates during concentrated flow. This study is the first one to investigate systematically the erosion‐reducing potential of the root properties of representative dike vegetation communities in a temperate humid climate. Results show that the presence of Urtica dioica resulted in large differences in root length density (RLD) among dike vegetation communities. Observed RLD values in the topsoil ranged from 129 to 235 km m^‐3 for dike vegetation communities without U. dioica, while smaller values ranging from 22 to 58 km m^?3 were found for vegetation communities with U. dioica. The erosion‐reducing effect of the dike vegetation communities was estimated based on a global Hill curve model, linking the RLD to the soil detachment ratio (SDR; i.e. the ratio of the soil detachment rate for root‐permeated topsoils to the soil detachment rate for root‐free topsoils). Concentrated flow erosion rates are likely to be reduced to 13–16% of the erosion rates for root‐free topsoils if U. dioica is absent compared to 22–30% for vegetation communities with U. dioica. Hence, to maintain a high resistance of the soil against concentrated flow erosion it is important to avoid the overgrowth of grassland by U. dioica through an effective vegetation management. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   

Long time-series spatiotemporal variations of NPP and water use efficiency in the lower Heihe River Basin with serious water scarcity     

《Physics and Chemistry of the Earth》2016

It is of great significance to analyze the long time-series spatiotemporal dynamics of water use efficiency (WUE) to formulating appropriate management measures in response to the growing water scarcity in arid and semi-arid regions. This study analyzed the long time-series variations of WUE in the Lower Heihe River Basin, a typical arid and semi-arid region in China. The net primary productivity (NPP) was first estimated with the C-fix model, then WUE during 2001–2010 was calculated with the NPP and evapotranspiration (ET) data, and the accumulative WUE was further calculated. The results showed that the annual NPP and WUE in the study area ranged from zero to 448.70 gC/(m² a) and from zero to 2.20 gC kg⁻¹ H₂O, respectively, both of which showed an overall increasing trend during 2001–2010. Besides, the spatial pattern of WUE kept overall unchanged during 2001–2010, but with remarkable change in some part of the study area. In addition, the accumulative WUE of the whole study area showed a first sharply decreasing and then gradually increasing trend, but there was still some scope to improve the WUE, and it is necessary to carry out some more specific policies to further improve the water allocation and WUE within the Lower Heihe River Basin. Although with some uncertainties, these results still can provide valuable reference information for improving the water resource management and ecological conservation to guarantee provision of essential ecosystem services in arid and semi-arid regions.  相似文献