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1.
2004年全国防震减灾工作会议和《国务院关于加强防震减灾工作的通知》明确了今后一个时期防震减灾工作方向和主要工作任务,同时把防震减灾宣传工作提到了前所未有的高度。本文通过总结山西省防震减灾宣传工作实践,结合新时期防震减灾工作的要求,就进一步做好防震减灾宣传工作提  相似文献   

2.
李玉柱 《高原地震》2007,19(2):84-84
防震减灾是一项关系国计民生的重要工作,健全和完善地震工作机构是加强防震减灾工作中的一项必要措施。基层地震工作机构是否能够正常开展工作,直接影响防震减灾工作的顺利进行。从近几年的实际情况看,基层地震工作机构的现状还远远不能满足工作需要。  相似文献   

3.
郑仙蓉 《地球》2014,(2):12-15
1月16日至17日,全国粮食流通工作会议在北京召开。会议认真贯彻党的十八届三中全会精神,全面落实中央经济工作会议、中央农村工作会议关于粮食工作的决策部署,传达贯彻国务院领导同志最近关于粮食流通工作的重要批示精神,总结交流2013年粮食流通工作,分析当前面临的形势,研究部署2014年工作任务。同时召开了全国粮食纪枪监察工作会议。  相似文献   

4.
正1月16日至17日,全国粮食流通工作会议在北京召开。会议认真贯彻党的十八届三中全会精神,全面落实中央经济工作会议、中央农村工作会议关于粮食工作的决策部署,传达贯彻国务院领导同志最近关于粮食流通工作的重要批示精神,总结交流2013年粮食流通工作,分析当前面临的形势,研究部署2014年工作任务。同时召开了全国粮食纪检监察工作会议。会议认真学习了习近平总书记关于粮食安全和粮食工作一系列重要讲话精神,传达学习了李克强总理和张高丽副总理、汪洋副总理最近对粮食流通工作作出的重要批示。与会代表  相似文献   

5.
《地球》2015,(1):1-3
<正>在2015全国国土资源工作会议上,国土资源部部长、党组书记、国家土地总督察姜大明发表重要讲话。姜大明指出,这次国土资源工作会议的主要任务是,深入贯彻党的十八大和十八届三中、四中全会精神,全面落实中央经济工作会议和农村工作会议部署,分析经济发展新常态下国土资源工作面临的形势任务,总结2014年工作情况,部署2015年重点工作。姜大明表示,2014年,国际环境复杂多变,世界经济  相似文献   

6.
县级地震工作机构是防震减灾事业发展的基础,工作任务繁重,责任重大。通过对云南省县级地震工作机构现状的调查与分析,归纳了云南省县级防震减灾工作发展过程及其作用,探讨了进一步推进工作的思路与措施,并对云南省县级防震减灾工作的发展前景进行了展望。  相似文献   

7.
城市是我国防震减灾工作的重点,建国以来我国城市防震减灾工作历经数次调整,形成了符合当前实际的工作思路.本文阐述了城市防震减灾工作的特殊性和重要性,并针对我国城市防震工作存在的一些问题,提出了若干工作建议和措施.  相似文献   

8.
地震群测群防工作是我国防震减灾工作的重要组成部分,是国家鼓励、引导社会组织和个人开展地震群测群防活动的重要途径。本文在认真回顾山东省群测群防工作发展历程的基础上,结合山东省群测群防工作的实践经验,从5个方面归纳介绍了山东省群测群防工作的有效作法,并展望了进一步深入开展地震群测群防工作的发展空间。  相似文献   

9.
地震现场监测工作   总被引:2,自引:2,他引:0  
破坏性地震发生后,立即开展地震现场监测工作尤为重要。论文概述了地震现场监测工作的主要任务和组织管理规定,重点分析中国大陆6次强地震发生后现场监测工作,通过总结已有工作经验,就进一步提高地震现场监测效能提出相关建议,认为应扎实做好准备工作,健全制度,提高地震现场监测工作现代化和智能化水平。  相似文献   

10.
对推进地震预测、预报工作的一些政策问题的讨论   总被引:2,自引:0,他引:2  
推进地震预测、预报不能只是地震局工作的改进,国家对待地震预测、预报的工作必须有一个政策的调整。当前地震预测预报工作基本上沿用气象工作的模式,但地震预报和气象预报的水平完全不在一个水平上。地震预测预报工作要把科学研究放到首位,在地震工作的管理体制、财政体制方面都应有一个大的调整。  相似文献   

11.
为研究斜腿夹角对V形墩连续刚构桥地震响应的影响及合理斜腿夹角角度,以一座典型V形墩预应力混凝土连续刚构桥为研究对象,采用有限元分析方法研究了斜腿夹角θ对桥梁内力及位移的影响,得出了θ对结构地震响应的影响规律和变化曲线。研究结果表明:随着斜腿夹角的增加,在纵向地震力作用下,墩底纵向弯矩逐渐减小,墩顶和主梁墩顶支撑处纵向弯矩逐渐增大;在横向地震力作用下,跨中横向弯矩逐渐减小,墩底横向弯矩逐渐增大,墩顶横向弯矩基本不变;在竖向地震力作用下,墩底和墩顶竖向弯矩逐渐增大,主梁支撑处竖向弯矩逐渐减小;斜腿夹角对纵向或横向地震力作用下结构位移影响不大,对竖向地震力作用下的位移影响较大。在满足静力设计的前提下,当两斜腿夹角为90°时,结构地震响应相对较小,受力合理性最优。研究成果可为该类桥梁的抗震设计与斜腿夹角角度选取提供参考和依据。  相似文献   

12.
The spatial and temporal distribution of physical, chemical and biological variables of the NE continental shelf of the Gulf of Cadiz were analyzed monthly during almost three annual cycles. This analysis was performed with the aim of deriving the main forcing factors controlling variability at inter-annual, seasonal and short-time scales. Meteorological forcing related to heavy episodes of rainfall that affected river discharges and the wind regime, controlled both the currents along the shelf together and the nutrient concentrations of the surface waters. Meteorological forcing in turn determined the subsequent development and maintenance of phytoplankton blooms. Superimposed on the seasonal cycle typical of temperate latitudes, the inputs of continental nutrients mainly from the Guadalquivir River, along with episodes of upwelling favored by the predominance of westerly winds triggered phytoplankton growth on the shelf, highlighting the markedly relevant role of this large estuary in the control of the biological activity on the shelf.  相似文献   

13.
This paper gives analytical expressions for the 1-D and 2-D frequency spectra of the self-potential field produced by a polarized sphere. In 1-D, the amplitude spectrum of the potential field leads to a criterion for determination of the depthh to the centre of the sphere. The polarization angle of the buried sphere can be calculated from the maximum point of the amplitude spectrum of the electric field. In 2-D, the depth to the centre of the polarized sphere can be calculated if the polarization is vertical.  相似文献   

14.
Twentyfive years of research on the effects of acid rain on rivers and lakes has, to a very small extent, documented changes in the nature and properties of natural organic matter (NOM). In Western Norway, a "whole-watershed-artificial-acidification-experiment" took place in the period 1988–1996. The goals of this long-term experiment were to study the role of NOM in acidification of surface water and the effects of acid precipitation on the quality and properties of NOM. In the HUMEX project (Humic Lake Acidification Experiment) one half of a lake and the corresponding catchment was artificially acidified with H2SO4 and NH4NO3 over a period of 5 years. The other half of the lake and catchment served as a control. In addition to monitoring of the general chemical composition of the water from the two lake halves, a number of other chemical and biological characteristics were studied. Here, we report the results related to changes in the nature and chemical properties of NOM. During the first few years of acidification, a significantly lower concentration of NOM was recorded in the acidified half of the catchment, compared with the control. However, statistical analyses of all data (covering a 2-years pre-treatment period and 5 years of treatment) related to the concentration of NOM (TOC, colour, and UV absorbance) did not suggest any significant effect on the quantity of NOM. This apparent discrepancy between the initial decrease in the concentration of NOM and no effect when the whole 5-years period is considered, may be due to the results of two different simultaneous processes. The results suggest that there first was a reduction of TOC and colour, as a consequence of the acidification, followed by an increase, perhaps owing to increased fertilisation (nitrogen) and in addition to a general temperature increase during the period. In addition, short-term studies of the aquatic surface microlayers, lipophilicity of the NOM, content of organic sulfur, and molecular size indicate differences in the quality of the NOM between the two lake halves, which could affect light absorption.  相似文献   

15.
随着我国医疗保险制度的全面实施和逐步完善和医疗保障体制改革的深入开展,我国医疗卫生行业必将引进社会主义经济体制下的宏观调控和市场竞争机制,这无疑有利于我国卫生事业的健康发展。面对当今科技进步与医院建设的新形势,对开展医院医疗仪器设备的管理提出了挑战。为此,本文探讨了在医院中,医学影像设备管理的几个问题和解决的方案。  相似文献   

16.
In this study, we examine the development of topography on a thin dense layer at the base of the lower mantle. The effect of the convecting mantle above is represented as a traction acting on the upper surface of the layer. Topography on the layer boundaries is predicted by a balance of dynamic flow stress and external traction. The nature of boundary topography depends on the magnitude of the driving tractions and the density variation within the layer. If we assume that the layer density is greatest beneath areas of mantle downwelling and decreases to a minimum beneath areas of mantle upwelling (the layer is thermally coupled to the convection in the overlying mantle) then its upper boundary develops a cusp-like peak beneath the upwelling mantle. The height of this peak is potentially much greater than the layer thickness. If, however, the layers are effectively coupled by viscous shear then internal density gradients of the opposite sign may be established. In this case, we observe solutions where the layer is completely swept away beneath areas of mantle downwelling leaving steep-sided ‘islands’ of dense material. This mechanism therefore provides a possible explanation for steep-sided anomalously slow regions at the base of the mantle observed by seismic methods (e.g. beneath south Africa) or for discrete ultralow velocity zones detected at the core-mantle boundary beneath locations of surface hotspots. The magnitude of the upper boundary driving tractions compared to the density gradient within the layer is the key parameter that determines the nature of flow in, and consequently boundary topography of, the layer. The deflection of the core-mantle boundary is small compared with that of the top of the dense layer, but a change in sign of the ratio of these deflections is observed as the magnitude of the driving tractions changes relative to the magnitude of the internal density gradient. We compare seismic measurements of core-mantle boundary topography and D′′ topography with the predictions of this model in an attempt to constrain model parameters, but no clear correlation seems to exist between D′′ thickness and CMB topography.  相似文献   

17.
We present a methodology conducive to the application of a Galerkin model order reduction technique, Proper Orthogonal Decomposition (POD), to solve a groundwater flow problem driven by spatially distributed stochastic forcing terms. Typical applications of POD to reducing time-dependent deterministic partial differential equations (PDEs) involve solving the governing PDE at some observation times (termed snapshots), which are then used in the order reduction of the problem. Here, the application of POD to solve the stochastic flow problem relies on selecting the snapshots in the probability space of the random quantity of interest. This allows casting a standard Monte Carlo (MC) solution of the groundwater flow field into a Reduced Order Monte Carlo (ROMC) framework. We explore the robustness of the ROMC methodology by way of a set of numerical examples involving two-dimensional steady-state groundwater flow taking place within an aquifer of uniform hydraulic properties and subject to a randomly distributed recharge. We analyze the impact of (i) the number of snapshots selected from the hydraulic heads probability space, (ii) the associated number of principal components, and (iii) the key geostatistical parameters describing the heterogeneity of the distributed recharge on the performance of the method. We find that our ROMC scheme can improve significantly the computational efficiency of a standard MC framework while keeping the same degree of accuracy in providing the leading statistical moments (i.e. mean and covariance) as well as the sample probability density of the state variable of interest.  相似文献   

18.
Nitrification – Fundamentals of the Metabolism and Problems at the Use of Ammonia Oxidizers From an ecological point of view, a great problem results from the release of increasing amounts of inorganic and organic nitrogen compounds. Apart from gaseous nitrogen compounds, such as the greenhouse gas N2O, soluble nitrogen compounds such as ammonium cause difficulties. In recent years, great progress has been made regarding the reduction of the emission of sulfur and phosphorus compounds. Since there are no effective strategies for the decrease of nitrogen releases, the emission of such compounds has even been increasing. Therefore, great efforts are being made to eliminate the soluble nitrogen compounds in particular, for example in wastewater treatment plants. A decisive meaning befits the chemolithoautotrophic ammonia oxidizers. This review focuses on the ecological consequences of the release of ammonia in particular, the metabolism of the ammonia oxidizing microorganisms under consideration of the latest research results, and the problems that arise in the context of using these bacteria for the removal of ammonia.  相似文献   

19.
林婷婷  林小雪  万玲  杨莹 《地球物理学报》1954,63(11):4256-4267
地面磁共振方法探测地下水趋于成熟.随着研究的深入,磁共振技术在隧道超前探测方面也开展了应用.然而,由于隧道空间特殊环境限制,获取的磁共振信号信噪比极低,解释结果中各参数的确定性值得深思.基于这一问题,本文提出隧道磁共振测深超前探测模型参数不确定度分析方案,实际工作前,根据不同探测目标要求及环境噪声水平,优化仪器装置参数设计,提高解释结果准确性.本文首先在地面磁共振探测理论基础上,推导了考虑天线铺设角度影响的隧道矩形线圈激发场计算表达式,模拟了隧道准全空间磁共振测深正演响应.其次,基于后验模型协方差矩阵,计算模型参数标准偏差因子,划分参数不确定度等级.最后,构建三层含水模型,将第二层含水体作为观测目标.在仿真合成数据的基础上,分别探讨了电阻率、含水量、水体厚度、线圈边长、匝数、线圈旋转角度以及噪声水平等参数对目标含水体测定的影响.通过对比分析,得到如下结论:当探测目标前方地层的电阻率小于10 Ωm时,目标含水体的不确定度随着该电阻率的增大而降低;当该电阻率大于10 Ωm时,其不影响目标含水体的不确定度;目标体前方地层含水量的增大能够明显增加目标含水体的不确定度;目标层电阻率以及含水量对该层含水体的不确定度几乎不造成影响;目标层厚度越大其含水体的确定度越高;线圈边长和匝数的增大都能在很大程度上降低含水体的不确定度;线圈的偏转角度不影响目标体的不确定度;磁共振信号中噪声的幅度越大,含水体参数的不确定度越大.本文的研究结论有助于提高隧道磁共振探测数据反演参数的准确性,同时能够为实际探测提供预先优化参数的分析方案.  相似文献   

20.
为了研究水平地震作用下桥梁结构及地铁设施的相互影响,以山西省太原市解放路改造工程为依托工程,分别建立了高架桥、地铁站、高架桥及地铁设施组合结构的三维动力有限元模型,并考虑设置碎石隔震层,进行不同工况下结构的抗震性能分析。结果表明:由于碎石层的缓冲隔震作用,组合结构中高架桥的桥墩内力更小,且地震作用越大时,内力减小程度越大;另一方面,高架桥的建造对地铁结构的抗震性能影响较小。此外,对于桥梁结构而言,碎石层的厚度变化对桥墩内力有一定影响,但影响程度较小;而对于地铁结构而言,碎石层厚度越小,地铁柱剪力弯矩值往往会越大,但增加幅度有限。  相似文献   

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