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针对水上复杂多变的环境给无人艇(USV)控制带来的不确定性干扰,提出基于二型模糊控制算法的USV航向航速控制器,并运用所提算法研制一套智能自主稳健的控制系统。
构建USV航向航速运动特性模型,利用递推最小二乘法(RLS)对航向航速运动特性模型进行参数辨识,基于辨识的航向航速运动特性模型分别设计二型模糊控制算法和滑模控制算法,并进行实艇验证试验。
结果表明,相较于滑模控制算法,二型模糊控制算法在控制USV时表现出了较好的鲁棒性,具有较理想的抗干扰能力,但在实时响应方面略长。
研究结果可为在不确定干扰环境下的USV运动控制提供参考。
955.
南京地铁2号线跨仙林大道斜拉桥为国内首座采用单索面的曲线地铁斜拉桥,以其为工程背景,介绍该桥的景观设计、结构设计及施工方案,阐述该桥与常规单索面直线斜拉桥的不同之处及其技术难点,为类似桥梁的设计提供参考. 相似文献
956.
Ella Graham-Rowe Stephen Skippon 《Transportation Research Part A: Policy and Practice》2011,45(5):401-418
Transport accounts for nearly a quarter of current energy-related carbon dioxide emissions with car travel constituting more than three quarters of all vehicle kilometres travelled. Interventions to change transport behaviour, and especially to reduce car use, could reduce CO2 emissions from road transport more quickly than technological measures. It is unclear, however, which interventions are effective in reducing car use and what the likely impact of these interventions would be on CO2 emissions. A two-stage systematic search was conducted focusing on reviews published since 2000 and primary intervention evaluations referenced therein. Sixty-nine reviews were considered and 47 primary evaluations found. These reported 77 intervention evaluations, including measures of car-use reduction. Evaluations of interventions varied widely in the methods they employed and the outcomes measures they reported. It was not possible to synthesise the findings using meta-analysis. Overall, the evidence base was found to be weak. Only 12 of the 77 evaluations were judged to be methodologically strong, and only half of these found that the intervention being evaluated reduced car use. A number of intervention approaches were identified as potentially effective but, given the small number of methodologically strong studies, it is difficult to draw robust conclusions from current evidence. More methodologically sound research is needed in this area. 相似文献
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介绍盐田港二期3个5万吨级集装箱码头结构的计算原则,基桩类型及其结构型式,沉桩控制标准及嵌岩桩、锚定桩、锚定嵌桩的施工机具和施工方法,还介绍了采用高应变动力试验与静载试验相结合的方法验证工程桩实际承载力的情况。 相似文献
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S. J. Lee S. J. Jeong W. S. Kim C. B. Lee 《International Journal of Automotive Technology》2008,9(6):659-670
The use of a diesel particulate filter (DPF) in a diesel aftertreatment system has proven to be an effective and efficient
method for removing particulate matter (PM) in order to meet more stringent emission regulations without hurting engine performance.
One of the favorable PM regeneration technologies is the NO2-assisted regeneration method due to the capability of continuous regeneration of PM under a much lower temperature than that
of thermal regeneration. In the present study, the thermal behavior of the monolith during regeneration and the conversion
efficiency of NO2 from NO with an integrated exhaust system of a diesel oxidation catalyst (DOC) and DPF have been predicted by one-channel
numerical simulation. The simulation results of the DOC, DPF, and integrated DOC-DPF models are compared with experimental
data to verify the accuracy of the present model for the integrated DOC and DPF modeling. The effects of catalyst loading
inside the DOC and the volume ratio between the DOC and DPF on the pressure drop, the conversion efficiency, and the oxidation
rate of PM, have been numerically investigated. The results indicate that the case of the volume ratio of ‘DOC/DPF=1.5’ within
the same diameter of both monoliths produced close to the maximum conversion efficiency and oxidation rate of PM. Under the
engine operating condition of 175 kW at 2200 rpm, 100% load with a displacement of 8.1, approximately 55 g/ft3 of catalyst (Pt) loading inside the DOC with the active Pt surface of 5.3 m2/gpt was enough to maximize the conversion efficiency and oxidation rate of PM. 相似文献
960.
文中采用溶胶-凝胶法,以正硅酸乙酯(TEOS)为硅源,氨水为催化剂,醇为溶剂,制备了 SiO2微球,并研究了正硅酸乙酯添加方式、溶剂类型、反应温度对其形貌和粒径的影响。通过 SEM,XRD,FT - IR,UV - Vis 测试分析 SiO2微球的形貌、结构、成分以及光学性能。结果表明,正硅酸乙酯水解对醇溶剂有选择性,乙醇作为溶剂合成 SiO2的分散性和球形较好,溶剂类型对 SiO2紫外吸收影响不大,SiO2对200~250 nm 紫外线吸收最强。逐步滴定法更利于 SiO2的合成,而 TEOS 添加方式对其非晶化程度影响不大。温度变化会影响氨水催化效率,进而会影响生成 SiO2的粒径。 相似文献