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31.
加入世界贸易组织以后我国测绘人才工作面临的挑战是严峻的。形势要求我们必须更加重视人才队伍建设 ,抓紧培养和造就一批更能适应今后测绘事业发展需要的测绘人才队伍 相似文献
32.
南黄海海域的中、古生代海相油气前景广阔,是重要的油气战略接替基地。由于多期构造运动的改造作用,原型盆地遭受强烈破坏,地质构造复杂,地球物理勘探精度低,造成对地层与构造认识不清,油气分布规律不明。针对勘探中面临的主要问题,提出的主要对策是:重点开展地球物理勘探技术创新研究与攻关试验工作,提高方法技术的适用性与有效性;在大地构造理论的指导下,重点开展多期构造活动背景下有效烃源岩、储层、保存条件等因素的研究工作,对区域油气地质条件优越且地层、岩性等特征存在争议的局部构造实施科学钻探等。 相似文献
33.
赵慧颖 《地质灾害与环境保护》2006,17(4):85-87
在分析呼伦贝尔市旱涝灾害的基础上,为了更好地减轻其损失,建立了“历史相似综合评估”和“气候背景统计评估”两个旱涝灾害经济损失评估模型。经5年的业务应用,效果很好。可以投入辅助决策服务使用。 相似文献
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35.
通过绵阳市普明街道鹏业小区边坡调查,研究了暴雨对边坡影响、变形破坏的特征和形成条件。研究表明:(1)边坡在暴雨后,北侧边坡形破坏发生明显变形破坏,北段上部墙体滑移开裂;(2)边坡的岩性、结构对滑塌的发育分布起控制作用,暴雨是滑塌的主要诱发因素;(3)计算表明北部边坡现状条件下处于基本稳定状态,在强降雨作用下,会发生大面积的滑移变形破坏。(4)建议对已滑塌地段采取清除损毁墙体后,用钢筋混凝土板墙加格构锚索进行修复,对未滑塌地段采取格构加锚杆进行护面墙体加固处理。 相似文献
36.
Farmers are both the producers and consumers of food, and as such have a dual role in food safety: they both generate risks and are exposed to them. Based upon a survey of the food production and consumption habits of 140 farm households and long-term research in two villages in Yunnan province, this study found that rural families are highly dependent on the market for food production and consumption. In their role as consumers, farmers are aware of food safety risks and concerned about them, but their ability to protect themselves is limited. They do so primarily by avoiding certain products and growing as much of their own food as possible. At the same time, in their role as producers, farmers engage in practices, primarily the overuse and inappropriate use of fertilizer and pesticides, that are damaging to food safety and the environment. There is therefore a disconnect in their roles as consumers and producers that needs to be addressed if policy goals for improving food safety and reducing the use of agricultural chemicals are to be achieved. Farmers need more information about food safety risks related to the products they consume themselves, and technical guidance on the safe use of farm chemicals when growing food for market. However, such measures will not be effective unless the external pressures on farmers are also addressed, through consideration of market incentives to use farm chemicals and the impact of consumer demand. 相似文献
37.
木里地区地处青藏高原的高寒地区,属于生态缺水区。运用综合污染指数法对该地区的地表水环境质量做出了初步评价,结果表明:该区挥发酚的污染指数为0.40,污染分担率为57.2%,远高于其它指标,但其含量〈0.002mg/L,基本无污染;其它污染物污染等级均属于清洁级;水质基本达到地表水环境质量Ⅲ级标准。随着木里煤田煤炭资源的开发利用,该地区的水环境质量和水体生态环境有污染的趋势。提出了建设小型调蓄、引水工程,加强点源和面源污染管理的防治对策及建议。 相似文献
38.
The time series of the dynamic response of a slender marine structure was predicted in approximate sense using a truncated quadratic Volterra series. The wave-structure interaction system was identified using the NARX (Nonlinear Autoregressive with Exogenous Input) technique, and the network parameters were determined through supervised training using prepared datasets. The dataset used for network training was obtained by nonlinear finite element analysis of the slender marine structure under random ocean waves of white noise. The nonlinearities involved in the analysis were both large deformation of the structure under consideration and the quadratic term of the relative velocity between the water particle and structure in the Morison formula. The linear and quadratic frequency response functions of the given system were extracted using the multi-tone harmonic probing method and the time series of the response of the structure was predicted using the quadratic Volterra series. To check the applicability of the method, the response of a slender marine structure under a realistic ocean wave environment with a given significant wave height and modal period was predicted and compared with the nonlinear time domain simulation results. The predicted time series of the response of structure with quadratic Volterra series successfully captured the slowly varying response with reasonably good accuracy. This method can be used to predict the response of the slender offshore structure exposed to a Morison type load without relying on the computationally expensive time domain analysis, especially for screening purposes. 相似文献
39.
世界软件产业发展的特点和地理构成 总被引:2,自引:0,他引:2
近几十年来,软件产业作为高效、低耗的绿色产业正在全球蓬勃发展。软件产业作为先导型的高技术产业,不仅顺应了当今“绿色”发展的国际潮流,也非常适合人均资源相对不足的中国经济的可持续发展。文章分析了世界软件产业的特征、发展现状、发展趋势和中国软件产业发展的状况,并提出了进一步发展的几点建议。 相似文献
40.
化工矿山企(事)业单位面对市场,在开展多种经营工作中,已进行了不同形式的探索。为进一步提高市场竞争能力,需根据矿山实际,认清优势、扬长避短、注重效益、充分发挥科技和人才的作用、做好综合利用及环境治理等工作。针对行业面临的困难,除努力挖掘自身潜力之外,尚需给予资金和政策方面的扶持。 相似文献