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991.
阮于洲 《测绘与空间地理信息》2011,34(1):202-204,207
测绘发展战略研究是国家层面战略研究--国家可持续发展国土资源战略研究的一个子课题.本文对测绘发展战略研究工作的意义、当前测绘事业发展面临的形势进行了分析,对测绘发展战略研究应遵循的基本要求进行了思考. 相似文献
992.
Wei Shen 《Climate Policy》2013,13(3):339-354
This article explores the incentives and challenges for Chinese business companies in participating in carbon emissions trading schemes (ETSs). Based on extensive interviews with the business managers and government officers who are currently involved in the ongoing policy experiments of pilot ETS programmes across China, the article identifies factors that either motivate or discourage companies in participating in carbon trading activities. It argues that different business groups, i.e. capped enterprises, uncapped enterprises, and carbon intermediaries, are affected by these factors to significantly different extents in terms of formulating their specific carbon strategies. It also illustrates some factors, such as a lack of stakeholder pressure and fragmented political interests, which have a distinctive Chinese character and are believed will have a fundamental impact on the quality and efficiency of Chinese ETSs in the future.Policy relevanceAt the outset, the successful implementation of any ETS depends critically on the active involvement of business actors across various industries. Hence, having an understanding of the business incentives and obstacles in participating in carbon trading is crucial, as these factors will ultimately determine the size and quality of the carbon market, and the total volume and integrity of the GHG emissions to be traded. This article also illustrates the common factors that affect business appetite for carbon trading throughout the world, as well as the factors that are unique to the Chinese political and economic context to constrain business in the market. Finally, a presentation of the business attitude towards the ETS experiment indicates the most worrying aspects of the policy design regarding carbon trading in China. As the construction and implementation of the ETS is a long-term undertaking, such investigation deserves attention from both policy makers and business leaders alike. 相似文献
993.
目前国内大多数无人机航测系统所采用的单相机平面精度可达到要求,但高程精度无法满足大比例尺测图要求。本文主要介绍一种无人机载双拼组合宽角相机低空航测系统,其组成结构、双拼组合宽角数码相机原理、数据处理软件,以及利用该系统进行大比例尺测图的生产流程。它与单相机系统的最大不同点是,通过双拼组合扩大了成像系统的旁向视场角,使得在等同航高条件下,航带影像地面覆盖宽度增加一倍,从而达到提高效率的目的。 相似文献
994.
整数相位钟法精密单点定位模糊度固定模型及效果分析 总被引:1,自引:1,他引:0
精密单点定位(PPP)模糊度固定方法有3种:星间单差法、整数相位钟法和钟差解耦法,但目前仅法国CNES公开发布用于整数相位钟法PPP模糊度固定的产品,因此研究基于整数相位钟法的用户端PPP模糊度固定模型很有必要.本文分析了整数相位钟法PPP模糊度固定模型,着重指出该模型与传统浮点解PPP模型的区别;提出一种顾及质量控制的逐级模糊度固定策略用于具体实施PPP模糊度固定.大量动态PPP解算试验表明:与浮点解PPP相比,固定解PPP具有更快的收敛速度且定位精度和稳定性更好. 相似文献
995.
996.
东海边际油气田类型主要有低渗透气田、复杂断块气田、微构造气田和高凝原油油气田等.在分析东海边际油气田开发特点和难点的基础上,按照区域整合、统筹兼顾的原则,提出了坚持勘探开发一体化,建立低渗开发先导试验区,打造区域设施中心、组建区域管网、电网,简化平台功能实现标准化设计,依托已建/拟建平台滚动扩边,论证FPSO方案作为原油外输第二出路的边际油气田开发策略,力求突破边际油气田开发壁垒,实现边际油气田低成本高效开发.其开发经验和策略对其它海域类似边际油气田高效开发具有一定的借鉴意义. 相似文献
997.
A discussion on improving typhoon observation through radar by scanning the negative elevation angle
Certain feasibilities and features were discussed in typhoon detection by radar with a negative elevation angle according to the relationship between the remote detecting range and the elevation angle of the new generation weather radar, in order to rectify the disadvantages of detecting capability for remote low-level echo with a lowest elevation angle of 0.5° in the common detecting mode. The data obtained from detecting the typhoon of Haitang and Changmi with radar for their negative elevation angles and the observed data for the common lowest elevation angle of 0.5° were compared to each other. The results showed that the detection of remote low level cloud system with radar could be improved by using the negative elevation angle, and the structure and the evolution trend of a typhoon could be better judged. The increasing degree of detection for negative elevation angles in the current volume scanning mode should be helpful for predicting the intensity and developing trend of windstorms, to further improve the capability of warning and nowcasting. The detection of negative elevation angle could also help reveal the development and change of typhoon's low level cloud system. As far as the typhoons of Haitang and Changmi were concerned, the detecting area of Changmi was increased by 1.09 times with the negative elevation angle of 0.31°, compared with the elevation angle of 0.48° if the threshold value for the sea echo within 100 km was eliminated. Several volume scans of Haitang were increased by 2.1%-7.9% for the negative elevation angle of 0.36° compared with the elevation angle of 0.49° . Therefore, the radar detecting capability of typhoons could be improved by the detection of negative elevation angles to some extent. This could make up for the disadvantages of a low detecting capability for remote low-level echo in the common detecting mode. At the same time, a negative elevation angle could be easily influenced by the ground clutter and the close sea wave clutter which interfered with the asses 相似文献
998.
目前海油低渗探明储量和低渗的产量分别占海油总探明储量和总产量比例虽然小,但在海油实现5 000万t年产后稳产阶段所起的作用将会越来越大。对于海上10~50 mD之间的一般低渗为主要考虑的勘探开发对象,当渗透率是5~10 mD之间的特低渗油田时需要优选出构造相对简单、储层比较连续的区块开发;对于复杂断块特低渗透油田和小于5 mD的超低渗油田,在目前海上经济技术条件下暂不具备勘探开发条件。在海上低渗透油田开发中需考虑压裂、注水的综合应用,尽量采用水平井和分支井开发,并且在开采过程中注意低渗储层的保护。 相似文献
999.
我国近海海洋油气产量接替现状与面临的问题及应对策略 总被引:1,自引:0,他引:1
我国海洋油气勘探开发经过近年来的发展,逐渐成为重要的储量与产量接替区.主要表现在:渤海盆地逐渐接替南海东部成为我国近海目前勘探前景最好、也是对我国油气储量和产量接替贡献最大的海区;南海西部通过重点地区、重要目的层和新区新领域的勘探突破,油气稳产前景良好;我国海上天然气剩余技术可采储量非常可观,产量增长比例上升迅速,成为... 相似文献
1000.
An improved particle swarm optimization algorithm with harmony strategy for the location of critical slip surface of slopes 总被引:1,自引:0,他引:1
The determination of optimal values for three parameters required in the original particle swarm optimization algorithm is very difficult.It is proposed that two new parameters simulating the harmony search strategy can be adopted instead of the three parameters which are required in the original particle swarm optimization algorithm to update the positions of all the particles.The improved particle swarm optimization is used in the location of the critical slip surface of soil slope,and it is found that the improved particle swarm optimization algorithm is insensitive to the two parameters while the original particle swarm optimization algorithm can be sensitive to its three parameters. 相似文献