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991.
Applications on iterative control and multiple input multiple output (MIMO) system were developed. Two new charts derived from extrinsic information transfer (EXIT) chart were employed as the designing tools, which are called as output mutual information chart with defined iterative degree (DID) chart and near optimum output mutual information (NOMI) chart respectively. Different from the EXIT chart, they can show the iterative performance on the whole signal-to-noise ratio range with one single curve, whereas computation complexity is greatly reduced compared with conventional bit error ratio (BER) performance curve. The iterative control was implemented according to a near-optimum iterative degree vector determined by NOMI chart, the reasonability of uncertain parameters was analyzed in one MIMO system. The concepts were illustrated based on bit-interleaved coded modulation with iterative decoding (BICM-ID). 相似文献
992.
Reflections on energy issues in China 总被引:2,自引:0,他引:2
江泽民 《上海交通大学学报(英文版)》2008,13(3):257-274
Energy, which has a bearing on both economic and national security, is of importance and a major constraining factor to the economic and social development of China. The article analyses the current worldenergy status and development trend from the perspectives of resources, production and consumption and in thecontext of its implications on the environment and economic and social development, and explores opportunitiesand challenges for China's energy development. With a focus on the strategy of energy development in China,the author proposes a new energy development approach with Chinese characteristics whose main elementsare: energy-saving, high-efficiency, diversified development, environment protection, technology guidance andinternational cooperation. In other words, China is striving to build a reliable energy production, circulationand consumption system that is efficient, technologically advanced, low polluting and ecologically friendly. Along-term development strategy with priority on energy conservation, efficient utilization of primary energyand advanced electricity system is expounded in the paper. The author also describes the prospect of energytechnology development and stresses the implementation of energy strategy by further improving energy policyand related mechanisms, strengthening macro-management and the essential role of the market in resourceallocation so as to ensure the economic and social development of China through reliable energy supply. 相似文献
993.
在路桥工程中,施工质量直接决定着工程整体质量.从软土地基本身的基本特点出发,阐述目前工程施工中面临的软土地基问题,并总结有针对性的施工技巧,可供广大同行参考. 相似文献
994.
为了缩短混合动力汽车开发时间,减少开发成本,本文以插电式并联混合动力汽车为研究对象,针对设计指标进行动力系统参数匹配以及使用AMESim软件搭建了整车模型,然后设计了基于门限值的能量管理策略并使用AMESim软件中的Signal,Control库进行搭建。之后对已搭建完成的车辆进行动力性经济性仿真分析,其中经济性分析是在NEDC工况下进行的,验证了本文所搭建策略和整车模型的正确性和可行性。 相似文献
995.
从地铁信息化建设的实际出发,提出了融合BIM(建筑信息模型)、GIS(地理信息系统)、SVG(可扩展矢量图)和其他业务数据的数字地铁信息资源集成模型。给出了数字地铁信息资源集成模型的数据构成和应用架构。通过上海轨道交通智慧车站的试点验证了模型的可行性。 相似文献
996.
ABSTRACTCost overruns are an endemic feature of the provision of transport infrastructure worldwide. In recent decades, a considerable amount of studies has been devoted to assessing the magnitude and determinants of cost overruns in the transportation sector. However, the empirical findings are scattered between different strands of literature, ranging from the fields of construction engineering and management to that of applied economics. To shed light on the determinants of cost overruns in the execution of transport infrastructure projects, we conduct a systematic review of the empirical literature on the topic. Of the 945 articles retrieved, 26 articles published between 2000 and 2016 meet our inclusion criteria. For them, we describe the different empirical approaches, we provide a classification of the determinants employed in the analyses and summarise their impact on cost overruns. Finally, we suggest some directions for further research in the field. 相似文献
997.
第三代完全数字化的系统技术使得公路信息采集和管理更加快捷,有效地提高了监督、决策及抢险指挥效率,为打造安全舒适的公路环境提供了有力保障。 相似文献
998.
计重收费是以收费站现场实际测量的车货总重为依据,对载货类机动车辆计重收取通行费的征收方式。文章对计重收费模式下货运车辆偷逃通行费的主要方式及特点进行了分析,阐述了当前车辆逃费治理工作中存在的困难及建议,提出了治理计重收费模式下货运车辆偷逃通行费的对策。 相似文献
999.
传统的物流外包决策方法忽略了物流服务交易市场中供需双方之间的消费偏好不相同,决策目标不一致,彼此信息不对称等客观因素.文中将多属性第一评分逆向拍卖模型引入物流服务交易机制设计中,扩展了物流服务投标者的成本函数类型,分析了其均衡策略,并给出了物流服务需求方的期望效用. 相似文献
1000.