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141.
台湾海峡是一个海雾多发的交通要道,海雾灾害往往会导致人员和财产损失。对当前有关的海雾研究现状进行总结,以海峡西岸为代表,比较台湾海峡海雾和其他海域的大雾研究进展状况,主要包括海雾发生时的天气气候学特征、监测手段、微物理特征研究和海雾数值预报研究等。结果表明,台湾海峡西岸在天气气候学方面已经取得了一定的成果;监测手段随着科学技术的发展,也不断的完善,但在如何对卫星遥感监测结果进行反演方面还需进一步研究;海雾的微物理特征研究有助于海雾模式的改进和卫星遥感海雾反演技术的提高,但台湾海峡西岸尚未开始研究,是下一步的研究重点;台湾海峡海雾数值模拟工作较少,伴随观测技术的不断进步、动力统计方法的不断完善,可通过数值预报产品与传统的天气学方法相结合,提高台湾海峡海雾预报水平。 相似文献
142.
根据重力梯度观测各分量的方差及协方差信息,提出了利用GOCE梯度数据计算径向重力梯度的优化方法。首先给出了径向重力梯度的计算方法,并深入分析了误差传播规律,通过建立相应的条件极值问题,给出了计算径向重力梯度最优组合因子的方法;通过模拟数据验证了本文所提出的优化因子的优越性。实际数据计算表明:相对于传统方法,采用优化组合因子可使反演所得引力位模型的累积大地水准面精度在250阶时提高约2 cm。由于径向重力梯度不仅可以用于地球引力场模型的求解,也可直接应用于地球物理问题的讨论,因此本文所提出的优化方法也可对部分地球动力学问题的讨论提供方便。 相似文献
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水质关键因素光谱遥感监测技术分析 总被引:1,自引:0,他引:1
针对传统水体水质分析方法过度依赖于实地测量和实验室化学分析,需要耗费大量人力物力且效率不高的问题,从水质遥感监测数据获取手段、典型反演监测模型、不同水体光谱遥感监测应用状况、水质遥感监测技术应用及前景等方面分析归纳了使用遥感技术监测水质的新方法。从可用数据类型、数据特征等方面对水质遥感监测数据获取的3种主要手段进行了比较;从复杂程度、使用场景、优缺点等方面对4种典型的反演模型进行了归纳;对遥感数据和模型在Ⅰ类和Ⅱ类水体应用中的常用组合方式进行了分析总结。 相似文献
145.
The bus route map is a diagram that aims to convey necessary information for map readers to find an appropriate way of moving from an origin to a destination. Design of bus route map is a complicated and time-consuming task that requires careful consideration of readability and aesthetics. This paper proposes a new computational method for designing bus route maps. The method helps us to reduce six types of undesirable elements in bus route maps, i.e., gap, shift, crossing, overlap, misalignment, and acute bend. The method consists of two phases: line layout phase determines the relative order of bus routes on each road segment and map layout phase calculates the actual position of bus routes drawn on a map. This paper applies the method to the design of bus route maps of Chiba City, Japan. The result supports the effectiveness of the method as well as reveals open topics for future research. 相似文献
146.
As a milestone of the entire energy industry, unconventional resources have inevitably swept the world in the last decade, and will certainly dominate the global oil and gas industry in the near future. Eventually, the “unconventional” will become “conventional”. Along with the rapid development, however, some issues have emerged, which are closely related to the viability of unconventional resources development. Under the current circumstances of low crude oil and gas price, coupled with the prominent environmental concerns, the arguments about the development and production of unconventional resources have been recently heated up. This work introduced the full-blown aspects of unconventional resources especially shale reservoirs, by discussing their concepts and definitions, reviewing the shale gas and shale oil development history and necessity, analyzing the shale plays’ geology and petroleum systems with respects to key hydrocarbon accumulation elements and mechanisms, and summarizing the technology resolution. This study also discussed the relevant key issues, including significant estimation uncertainty of technically recoverable resources, the equivocal understanding of complex geology preventing the production and technologies implementation optimization, the difficulties of experiences and technologies global expanding, and the corresponding risks and uncertainties. In addition, based on the latest production and exploration data, the future perspective of the unconventional resources was depicted from global unconventional resources assessments, technology development, and limitations constraining the development. 相似文献
147.
Analysis on Marine Science and Technology Strategy and Key Layout of Japan and the Inspirations to China 总被引:1,自引:0,他引:1
The Basic Ocean Law (BOL) and Basic Ocean Plan (BLP) are important guarantee for the maritime strategy of Japan, which has established a complete policy system for the development of marine science and technology. On the other hand, the Japanese Government has started some major marine strategies and plans to promote the BLP. In this paper, the marine science and technology plans launched by the Japanese Government and its participation in the international cooperative research projects were introduced. The research of Japan Marine Science and Technology Center and the University of Tokyo Institute of Oceanography in the long-term planning and focus on the layout features, deep sea research technology layout, contents and advanced equipment were analyzed. At last, some recommendations for China’s development on marine science and technology were proposed, such as strengthening the legislation work and process, carrying out research and development of marine infrastructure with independent intellectual property rights, actively participating in international large-scale ocean plan, improving the discourse right and enhancing national maritime awareness and suggestions and so on. 相似文献
148.
重点介绍了福建马坑矿区ZK8321分支孔受控定向钻进技术。施工中运用了国内先进的螺杆钻造斜技术及光纤陀螺测量定向技术,避开上部复杂孔段(松散破碎层、溶洞地层、采空区等)及对勘探工作的影响,达到了施工目的;总结了施工技术难点与措施,分析了施工技术效果,积累了宝贵的施工经验。 相似文献
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