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排序方式: 共有920条查询结果,搜索用时 93 毫秒
721.
722.
This paper researches how to apply the advanced control technology of model predictive control(MPC) to the design of the dynamic positioning system(DPS) of a semi-submersible platform.First,a linear low-frequency motion model with three degrees of freedom was established in the context of a semi-submersible platform.Second,a model predictive controller was designed based on a model which took the constraints of the system into account.Third,simulation was carried out to demonstrate the feasibility of the controller.The results show that the model predictive controller has good performance and good at dealing with the constraints of the system. 相似文献
723.
在具有水下岩基的港区、码头、航道施行拓深、拓宽的钻孔爆破船的快速移位和准确定位,是保证钻孔爆破船工作质量和施工效率至关重要的工序和过程。对传统的锚索定位方法和最时行的桩腿定位方法进行了阐述和比较,并展示了经创新设计的桩腿定位系统的结构和特点。 相似文献
724.
从分析规范对有二级动力定位的船舶推进系统的冗余要求出发,阐述了某起重铺管船冷却水系统为满足单个故障时的冗余要求而采取的措施:发电机组和系统分组,设备元件的冗余设置,以及冷却水系统的平衡。 相似文献
725.
726.
管道挖沟动力定位工程船是一艘集首部拖缆作业系统、尾部拖缆作业系统以及其他多项水下作业功能的海底施工作业船舶,为配合其作业功能,对诸多大型作业设备进行结构加强,并创新性地设计凹形首柱拖缆槽和导缆圆尾。通过计算分析,对横剖面进行优化,校核总纵强度以及校核主要设备加强结构的局部强度,对船体振动进行评估并采取一定的减振措施。 相似文献
727.
728.
In this paper, graphical-user-interface (GUI) software for simulation and fuzzy-logic control of a remotely operated vehicle (ROV) using MATLABTM GUI Designing Environment is proposed. The proposed ROV... 相似文献
729.
Driven by sustainability objectives, Australia like many nations in the developed world, is considering the option of battery electric vehicles (BEVs) as an alternative to conventional internal combustion engine vehicles (ICEVs). In addition to issues of capital and running costs, crucial questions remain over the specifications of such vehicles, particularly the required driving range, recharge time, re-charging infrastructure, performance, and other attributes that will be of importance to consumers. With this in mind, this paper assesses (hypothetically) the extent to which current car travel needs could be met by BEVs for a sample of motorists in Sydney assuming a home-based charging set-up, which is likely to be the primary option for early adopters of the technology. The approach uses five weeks of driving data recorded by GPS technology and builds up home-home tours to assess the distances between (in effect) charging possibilities. An energy consumption model based on characteristics of the vehicle, and the speeds recorded by the GPS is adapted to determine the charge used, while a battery recharge function is used to determine charging times based on the current battery level. Among the most pertinent findings are that over the five weeks, (i) BEVs with a range as low as 60 km and a simple home-charge set-up would be able to accommodate well over 90% of day-to-day driving, (ii) however the incidence of tours requiring out-of-home charging increases markedly for vehicles below 24 kWh (170 km range), (iii) recharge time in itself has little impact on the feasibility of BEVs because vehicles spend the majority of their time parked and (iv) effective range can be dramatically impacted by both how a vehicle is driven and use of electrical auxiliaries, and (v) while unsuitable for long, high-speed journeys without some external re-charging options, BEVs appear particularly suited for the majority of day-to-day city driving in big cities where average journey speeds of 34 km/h are close to optimal in terms of maximising vehicle range. The paper has implications for both policy-makers and auto manufacturers in breaking down some of the (perceived) barriers to greater uptake of BEVs in the future. 相似文献
730.