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Yusuke Yano Shinichi Takagawa Kazuyasu Wada 《Journal of Marine Science and Technology》2003,7(3):101-108
The Japan Marine Science and Technology Center (JAMSTEC) has been, and is now promoting the “OD21” program (i.e., “Ocean
drilling in the 21st century”). This is the first plan in the world to utilize deep-water riser-drilling technologies for
scientific drilling. One of the important factors for the success of this program is the development of a high-performance
drilling vessel. Since 1990, JAMSTEC has been continuing a technological study of a riser-drilling vessel for scientific studies
with an operational capability in waters up to 4000 m deep. It was decided to start the construction with a two-phase plan:
a vessel with a riser operation for waters up to 2500 m deep will be constructed in the initial stage, and then the vessel
will be modified to a 4000-m depth capability. In the development process of the vessel, named Chikyu, many new technical developments have taken place, such as drilling/coring equipment, a dynamic positioning system, etc.
Thus, the Chikyu is expected to contribute to ocean engineering and other work, in addition to scientific advances.
Received: June 15, 2002 / Accepted: November 11, 2002
Address correspondence to: Y. Yano (e-mail: yanoy@jamstec.go.jp) 相似文献
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Adithya Arikere Derong Yang Matthijs Klomp 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2019,57(5):637-664
Collision avoidance at intersections involving a host vehicle turning left across the path of an oncoming vehicle (Left Turn Across Path/Opposite Direction) have been studied in the past, but mostly using simplified interventions and rarely considering the possibility of crossing the intersection ahead of a bullet vehicle. Such a scenario where the driver preference is to avoid a collision by crossing the intersection ahead of a bullet vehicle is considered in this work. The optimal vehicle motion for collision avoidance in this scenario is determined analytically using a particle model within an optimal control framework. The optimal manoeuvres are then verified through numerical optimisations using a two-track vehicle model, where it was seen that the wheel forces followed the analytical global force angle result independently of the other wheels. A Modified Hamiltonian Algorithm controller for collision avoidance that uses the analytical optimal control solution is then implemented and tested in CarMaker simulations using a validated Volvo XC90 vehicle model. Simulation results showed that collision risk can be significantly reduced in this scenario using the proposed controller, and that more benefit can be expected in scenarios that require larger speed changes. 相似文献
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物流调查是物流设施规划与政策制定的重要基础。物流数据统计发展滞后已成为制约中国物流业发展的重要瓶颈。通过梳理日本在物流调查方面的工作进展,总结其在调查制度保障、组织模式、调查方案、调查内容及方法等方面的特点。针对中国物流行业发展现状,提出具体建议:加快开展货运需求调查的前瞻性研究,规范并指导企业构建统一的物流信息数据与平台,远期将货运调查纳入综合交通调查体系等。 相似文献