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1.
介绍了地震文书档案、科技档案、财会档案等不同类别的防震减灾档案的概况 ;总结了山西防震减灾档案在收集整理、开发利用过程中的规律和特点 ;叙述了加强防震减灾档案依法管理 ,建立健全规章制度 ,编写检索工具 ,提高编研质量 ,建立大震专题档案 ,创立山西地震档案文献信息系统 ,开发利用档案信息资源 ,实现科学化、规范化、现代化管理的经验和体会。  相似文献   

2.
何申红 《山西地震》2005,(Z1):42-42
地震科技档案以其独有的专业性、多样性、成套性和现实性为特征,它凝结着科技人员的心血和智慧,具有极珍贵的保存和开发利用价值,对指导地震科学研究起着举足轻重的作用.地震科学所表现出的探索性,地震观测项目的多样性,防震减灾涉及社会领域的广泛性,尤其以高科技为先导,地震科技现代化不断发展的新形势,决定了做好地震科技档案工作的重要意义.  相似文献   

3.
吴玉荣  王强 《高原地震》2003,15(4):63-66
地震科技档案鉴定是档案管理部门的一项重要工作。针对地震科技档案鉴定工作的重要意义进行了分析,定期对地震科技档案鉴定有利于优化馆藏、对重点地震科技档案的保管;并对提高档案工作服务水平和档案人员业务素质进行了探讨。  相似文献   

4.
紧紧围绕新常态下我国地震科技档案管理面临的新形势和新任务,分析了目前地震科技档案在管理制度、档案内容和提供服务利用等方面存在的问题,结合新常态下防震减灾工作需求,探讨并提出从做好地震科技档案的规划、丰富地震科技档案内容、争取实现地震科技档案的增值、不断提升地震科技档案社会服务的能力等几个方面来加强地震科技档案管理的对策和建议。  相似文献   

5.
了地震科技档案工作的现状及其存在的主要问题:了地震科技档案工作的发展趋势;最后提出了发展地震科技档案工作的对策。  相似文献   

6.
信息时代和科技体制改革给地震科技档案管理工作提出了新的要求。叙述了地震科技档案管理人员适应形势要求的体会,指出,只有转变观念.加强学习,不断提高业务素质,积极开发地震科技档案信息资源,努力提高地震科技档案的利用价值.才能开创科技档案为地震科研、防震减灾服务的新局面。  相似文献   

7.
信息化给地震科技档案工作带来了严峻的挑战,为了更好地发挥信息化在地震科技档案工作中的作用,就如何应用先进的设备和先进的技术实现地震科技档案管理现代化问题进行了阐述,对地震科技档案如何适应市场经济的需求提出了看法。  相似文献   

8.
1991年辽宁省地震科技档案工作会议7月23日至26曰在大连召开.出席会议的有省内各专业地震台、地震大队和省局情报资料室的代表共26人.省地震局副局长卢造勋同志出席了会议.会议总结交流了全省地震科技档案工作,检查了1990年地震科技档案;表彰了地震科技档案工作先进单位和个人.  相似文献   

9.
在总结辽宁省地震科技档案工作的基础上,就档案工作的意义、重要性、辽宁省地震科技档案工作的特点和今后工作展望等问题作了叙述。  相似文献   

10.
随着全国地震科技创新大会的召开和《国家地震科技创新规划》的实施,我国的防震减灾事业走上了快速发展的道路。如何为地震科技创新服务,是地震系统档案工作者面临的新课题。笔者从地震科技创新服务;积极推进档案数字化、网络化管理,实现数字档案室;深入开展创新型的档案宣传活动等几方面进行了阐述。  相似文献   

11.
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   

12.
Indicating the Trophic State of Running Waters by Using TIM (Trophic Index of Macrophytes) – Exemplary Implementation of a New Index in the River Inninger Bach The river Inninger Bach represents the outflow of the lake Wörthsee (Bavaria). The mean pH of the calcareous river has a value of ca. 8 during the vegetation period, the mean conductivity is about 350 to 400 μS/cm. The macrophyte vegetation of the river course was mapped and the nutrient concentrations of both the water body and the sediment were measured. In every mapping section the Trophic Index of Macrophytes (TIM) was calculated. By cluster analysis the mapping sections were grouped into three zones which differed in macrophyte vegetation. These differences are not associated with varying nutrient concentrations but are mainly due to differences in the degree of shading. In spite of the characterisation of the lake Wörthsee as oligo‐mesotrophic the river Inninger Bach, which represents the outflow of the lake Wörthsee, is classified as meso‐eutrophic by the Trophic Index of Macrophytes TIM. The increased trophic state of the river compared to the lake is caused by the river Krebsbach, a small tributary flowing into the river Inninger Bach only a short stretch downstream of its outflow of the lake Wörthsee. The river Krebsbach shows a total phosphorus concentration of about 56 μg/L P. The input of diaspores of submerged macrophytes both from the oligo‐mesotrophic lake Wörthsee and the eutrophic river Krebsbach leads to a submerged vegetation comprising species with different optima in regard to the trophic situation. This is one of the main reasons why many values of the TIM have to be labeled as “not sure”.  相似文献   

13.
通过大型地质力学模型试验,研究在无支挡结构下降雨对隧道-滑坡正交体系的作用机理。主要研究不同降雨阶段,隧道-滑坡正交体系下隧道纵向应变的变化特征及隧道不同横断面环向应力变化特点,并重点分析在不同降雨阶段,不同位置及其不同横断面滑体的位移变化特征。试验结果表明:(1)降雨可导致坡体横断面断裂而出现新的滑移面,从而导致坡体失稳。(2)在隧道-滑坡正交体系下,随着雨水的下渗及滑体土样含水率不断增大,隧道局部应变有明显突变,且山侧纵向应变比河侧应变要大。(3)在隧道-滑坡正交体系下,降雨使得隧道环向应力呈不均匀变化:隧道的底部应力大于顶部应力,山侧应力大于河侧应力,表明降雨可导致滑体蠕动或局部滑移,引起隧道不均匀受力及变形,这对隧道结构的安全非常不利。本次试验可为雨水充沛区的滑坡及隧道抗滑设计提供一定参考。  相似文献   

14.
ABSTRACT

The one-dimensional transient downward entry of water in unsaturated soils is investigated theoretically. The mathematical equation describing the infiltration process is derived by combining Darcy's dynamic equation of motion with the continuity and thermodynamic state equations adjusted for the unsaturated flow conditions. The resulting equation together with the corresponding initial and boundary conditions constitues a mathematical initial boundary value problem requiring the solution of a nonlinear partial differential equation of the parabolic type. The volumetric water content is taken as the dependent variable and the time and the position along the vertical direction are taken as the independent variables. The governing equation is of such nature that a solution exists for t > 0 and is uniquely determined if two relationships are defined, together with the specified state of the system, at the initial time t = 0 and at the two boundaries. The two required relations are those of pressure versus permeability and pressure versus volumetric water content.

Since the partial differential equation has strong non-linear terms, a discrete solution is obtained by approximating the derivatives with finite-differences at discrete mesh points in the solution domain and integrated for the corresponding initial and boundary conditions. The use of an implicit difference scheme is employed in order to generate a system of simultaneous non-linear equations that has to be solved for each time increment. For n mesh points the two boundary conditions provide two equations and the repetition of the recurrence formula provides n—2 equations, the total being n equations for each time increment. The solution of the system is obtained by matrix inversion and particularly with a back-substitution technique. The FORTRAN statements used for obtaining the solution with an electronic digital computer (IBM 704) are presented together with the input data.

Analysis of the errors involved in the numerical solution is made and the stability and convergence of the solution of the approximate difference equation to that of the differential equation is investigated. The method applied is that of making a Fourier series expansion of a whole line of errors and then following the progress of the general term of the series expansion and also the behavior of each constituent harmonic. The errors (forming a continuous function of points in an abstract Banach space) are represented by vectors with the Fourier coefficients constituting a second Banach space. The amplification factor of the difference equation is shown to be always less than unity which guarantees the stability of the employed implicit recurrence scheme.

Experiments conducted on a vertical column packed uniformly with very fine sand, show a satisfactory agreement between the theoretically and experimentally obtained values. Many experimental results are shown in an attempt to explain the infiltration phenomenon with emphasis on the shape and movement of the wet front, and the effects of the degree of compaction, initial water content and deaired water on the infiltration rate.  相似文献   

15.
16.
Desorption and bioaccumulation of Cd, Zn, and Pb were studied using naturally contaminated sediment from a brackish water pond in the Sunderban Biosphere Reserve in India. Pattern of desorption of the metals from the sediment and bioaccumulation in fingerlings of the teleost Oreochromis mossambicusand postlarvae of the shrimp Penaeus monodon were studied as a function of salinity and loading of detritus of a mangrove plant. Effects of both salinity and loading of detritus on bioaccumulation of the metals were studied under two conditions: either the animals were allowed free access to the sediment or access was denied. Ninety‐six hour experiments showed that desorption of Cd and Pb from sediment into water increased with salinity of the medium while desorption of Zn decreased. Salinity of the medium also had a significant effect on the bioaccumulation of metals by fish; Cd and Pb accumulation decreased in saline medium while the accumulation of Zn increased. Conditions of access to sediment had no effect on the bioaccumulation of metals by fish; effect of interaction between salinity and access condition was also insignificant. The access conditions, however, significantly influenced accumulation of metal by the shrimp postlarvae. The effect of interaction between salinity and access condition was insignificant in influencing the bioaccumulation of all metals except Zn. The accumulation of Zn increased as a function of the salinity of the medium when shrimp postlarvae were allowed access to the sediment. Desorption of metals from sediment to water were below detection limits when detritus of a mangrove plant was added to the medium. Both the level of detritus and the conditions of access influenced accumulation of metals by fish, but the effect of interaction between the two factors were found to be insignificant. Shrimp postlarvae showed net accumulation only of Pb in the presence of detritus and the accumulation of Pb increased when the larvae were separated from the sediment. The results are important in understanding the mobility of metals between solid and aqueous phases in brackish water environments that experience periodic fluctuations in salinity and fluxes of organic load in the form of mangrove detritus.  相似文献   

17.
本文以2021年2月13日和2022年3月16日日本福岛近海区域发生的Mw7.0和Mw7.3地震强震动数据为基础,从地震动的幅值、频谱、持时以及衰减关系等方面对比分析了强震动特征,解释了复发性地震的相似性,研究表明:当周期大于0.8s时,两个台站记录的加速度反应谱低于设计谱数值,对于长周期结构影响较小;随着场地和断层距的变化,同一台站在两次地震中加速度反应谱峰值对应的周期并没有发生明显的变化,在长周期部分,断层距较近的台站随着周期的增加反应谱下降的更快;两次地震中相应的PGA和PGV幅值呈对数线性关系;在等效卓越频率方面,2.0~4.0Hz范围内的离散点相对较少,解释了结构破坏较轻的现象;两次地震持时的回归曲线趋势相同,衰减相对较慢。  相似文献   

18.
龙门山中北段流域地貌特征及其构造意义   总被引:1,自引:1,他引:0  
龙门山中北段位于青藏高原东缘,该区作为高原向东扩展的前缘部位,其地形与河流水系的演化记录了高原隆升与挤压扩展及其气候环境效应的各种信息。龙门山中北段构造活动有明显差异,从中段逆冲为主转化为北段的走滑为主,本文采用定量化地貌参数从构造地貌的角度揭示了区域构造活动的差异。龙门山中北段地貌因子(坡度、地形起伏度和条带状剖面)的阶梯状分布特点,显示了高原扩展的逆冲推覆特征,在中央断裂处构造抬升作用最强,同时显示出了南北向构造活动减弱的趋势,由中段的逆冲转换为北段逆冲兼走滑的形式。北川-映秀断裂两侧流域的HI值也显示了断裂上盘高、下盘低、沿走向减弱的趋势。综合分析认为,本区构造活动是地貌演化的主控因素,龙门山中北段地形存在差异,北川-映秀断裂两侧的小流域地貌指数分析显示,构造抬升活动自南向北减弱,中段以逆冲为主,北段为逆冲兼走滑。  相似文献   

19.
现有大量观测记录表明:斜坡地形对地震波的传播有着非常强烈的影响。为服务于工程抗震设计,基于显式有限元方法,定量分析SH波垂直入射下二维斜坡地形的地震动响应与斜坡角度、土层厚度以及介质阻抗比的关系,总结了位于一维土层基本频率附近斜坡上台面各区域放大因子的变化规律。研究表明:(1)斜坡面对SH波的反射使二维斜坡地形的放大倍数较一维土层存在显著放大,且该现象在缓坡中更加明显。(2)当土层厚度为斜坡高度的1/4,介质阻抗比为0.368,坡度为30°时,放大因子在距坡顶1.67倍斜坡高度处取到最大值1.930。(3)斜坡覆盖土层薄时,放大因子受斜坡角度的影响大,斜坡覆盖土层厚时,阻抗比成为影响放大因子的主要因素。(4)分别考虑土层厚度、斜坡角度、介质阻抗比以及观测点位置对二维斜坡地形地表地震动响应的影响,取1倍斜坡高度作为区域间隔,统计每个区域内各参数对应的放大因子最大值,对比现有规范给出工程抗震设计参考值及放大因子大于1的基频比范围。  相似文献   

20.
砌体墙弹性计算采用的无转动假定与砌体房屋震害中所表现的墙体破坏模式不完全相符,砌体墙的转动变形是墙体受力过程中总变形的重要组成部分,转动失效也是一种典型的破坏模式。在前期试验研究基础上,进行了3片足尺门窗间砌体墙试件的低周反复荷载试验,立面形状为“凸”形和“L”形,介绍了试件的破坏过程及转动现象,分析了试件的滞回曲线和承载力差异;探讨了门窗间砌体窗间墙的转动变形机理,并分析了材料强度、竖向荷载和立面形状等因素对砌体墙转动变形的影响。研究结果表明:本文荷载及约束条件下,门窗间砌体墙试件均表现出明显的转动失效特征,属于窗间墙转动或窗间墙连带窗下墙整体转动失效的破坏模式;砌体墙发生受剪破坏或转动失效的关键在于窗间墙水平截面的受剪能力是否大于其受到的水平荷载;砌体材料强度越高、高宽比越大和立面对称性越差,砌体墙越容易出现转动变形现象以及发生转动失效,反之则容易发生受剪破坏。本文试验以及研究内容关注了门窗间砌体墙在受力全过程中实际存在而又常常被忽略的转动变形问题,试验数据及研究结论可为更加深入地了解砌体墙的变形机制提供参考。  相似文献   

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