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31.
There is a low nutrient level in the Aoshan Bay. In June 1999, the chemical adjustmentand control experiment was made in the Aoshan Bay. Following tracts investigation was carried out before the experiment and on the 1st, 2nd, 4th, 5th, 6th and 45th day/after the experiment. While the variance of amount of phytoplankton, the replacement of superior species and the species composition of phytoplankton were researched. The results show that the amount of phytoplankton in the Aoshan Bay rises gradually after the experiment. Ceratium macroceros Cleve of pyrophyta was the dominant species before the experiment, its dominant index was 37.7%. Six days after the experiment, its dominant index dropped to 17.6% . Meanwhile the dominant index of Asterionella japanics Cleve rose from 7.1% to 39.2% , it became the first dominant species. Forty-five days after the experiment, the amount of phytoplankton in the Aoshan Bay was 5.15 to 137.32 times more than that in 1997. 相似文献
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Generally, the underwater flight vehicle (UFV) depth control system operates with the following problems: it is a multi-input multi-output (MIMO) system, it requires robustness, a continuous control input, and further, it has the speed dependency of controller parameters. To solve these problems, an expanded adaptive fuzzy sliding mode controller (EAFSMC), which is based on the decomposition method designed by using an expert knowledge and the decoupled sub-controllers and composition method designed by using the fuzzy basis function expansions (FBFEs), is proposed. To verify the performance of the EAFSMC, the depth control of UFV in various operating conditions is performed. Simulation results show that the EAFSMC solves all problems experienced in the UFV depth control system online. 相似文献
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本方案采用850、700、500hPa三个层次的环境平均流场作控制点法。综合考虑这些层次上的引导气流在不同时、空域中的相对重要性。试验结果表明,其效果比单一取某层作引导为佳。且对用来预测台风的未来24小时路径是否异常具有一定的参考价值。 相似文献
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This paper proposes a nonlinear robust adaptive control strategy to force a six degrees of freedom underactuated underwater vehicle with only four actuators to follow a predefined path at a desired speed despite of the presence of environmental disturbances and vehicle’s unknown physical parameters. The proposed controller is designed using Lyapunov’s direct method, the popular backstepping and parameter projection techniques. The closed loop path following errors can be made arbitrarily small. Interestingly, it is shown that our developed control strategy is easily extendible to situations of practical importance such as parking and point-to-point navigation. Numerical simulations are provided to illustrate the effectiveness of the proposed methodology. 相似文献
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本文介绍了海洋技术研究所质量管理处在维护质量体系运行方面的主要作法和经验体会,结合2000版ISO9201标准的新内容,提出适应新版标准的想法。 相似文献
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具有匹配不确定的奇异摄动系统的鲁棒控制 总被引:2,自引:0,他引:2
对于同时具有结构匹配不确定和系统不确定量的奇异摄动系统,利用Lyapunov稳定性理论进行了鲁棒性研究。给出了1个理想奇异摄动系统的稳定鲁棒控制也是不确定奇异摄动系统稳定控制的稳定条件和鲁棒界,讨论了鲁棒界及其随参数变化的变化范围。本文是王宪杰,高存臣已有结果的推广。 相似文献
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In this paper, we focus on the status and trends of the current Korean fisheries management regime. Specifically, this paper briefly introduces the Korean conventional fisheries management regime (KCFMR) and discusses its problems and limitations. In describing policy evolution, this paper finds reasons why the Korean government has chosen a TAC system, an output control approach, besides input control approaches in force for almost a century. This paper also describes the evolution of the Korean TAC system, which is carrying out a pivotal role in Korean fisheries development, and analyzes problems of the Korean TAC system. Finally, this paper gives a perspective on expanding the Korean TAC system toward Output Control Systems (OCSs) such as Individual Quotas (IQs), Individual Vessel Quotas (IVQs), Individual Transferable Traps (ITTs), Community Quotas (CQs), and Individual Transferable Quotas (ITQs). 相似文献