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71.
This study considers a new design methodology in the context of active vehicle suspension control. The approach combines concepts from Stochastic Optimal Control with those of Learning Automata. A learning automaton effectively learns optimal control on-line in the vehicle, in an appropriate stochastic “test-track” environment. For practical application, the overwhelming advantage of this approach is that no explicit modelling is required, and considerable time savings may be expected in system development. This simulation study considers the on-line learning of optimal control in a low-bandwidth active suspension system, where control feedback is confined to a body-mounted accelerometer at each corner of the vehicle. It is shown that learning can successfully take place under a range of conditions, including the case when there is substantial transducer noise. The performance of the resulting control system is shown to depend heavily on the nature of the learning environment.  相似文献   
72.
Accurately estimating the SOC of a battery during the electric vehicle drive cycle is a vital issue that currently remains unresolved. A support vector regression algorithm (SVR), which has good nonlinear approximation ability, a quick convergence rate and global optimal solution, is proposed to estimate the battery SOC. First, the training data and the test data required in the estimation operation are collected using the ADVISOR software, followed by normalization of the data above. Then, cross validation and grid search methodologies are used to determine the parameters in the ν-SVR model. Finally, simulation experiments have been carried out in the LIBSVM simulator. The simulation results show that, compared to the BP neural network algorithm, the ν-Support Vector Regression algorithm performs better in estimating the battery SOC.  相似文献   
73.
As concerns of dynamic tensile measuring, a new tension mechanism driven by liner motor in high-speed tensile testing machine is presented. It satisfies the requirements for testing the dynamic tensile properties of plastic materials with strain rates from 1 to 100 s-1, which is relatively difficult to test for currently available machines. For this purpose the idle stroke principle is used to realize the dynamic load of plastic material with static grip. Computer aided engineering is used: i) to analyze and optimize the tension mechanism thus allowing reducing the system shock caused by collisions. ii) to avoid the influence of plastic materials specimen stress and strain uniformity on the measuring system. The analysis results agreed well with the established empirical relationships based on experimental evidence. Two sets of experiments for different strain rate tensile were conducted thus allowing proving the reliability and credibility of the designed tension mechanism.  相似文献   
74.
大众宝来,作为一款典型的德系紧凑型轿车,自2001年在中国上市以来,凭借其出色的制造工艺,灵活的操控性,高速行驶的稳定性,被消费者誉为“驾驶者之车”,并拥有了一大批忠实的拥趸,累计销量超过了37万辆。2008年10月,新款宝来隆重登场,尽管开始的几个月市场表现一直没有太多亮点,但2009年3月,新宝来的月销量猛蹿到10240辆,充分证明了这款在中国有着传统根基的德系车仍然有着不少的“粉丝”。  相似文献   
75.
Su G.  Zan Y.  Sun W.  Cai W.  Hu Q.  Liu X. 《现代隧道技术》2018,(6):170-175
The vehicle-mounted GPR technique, a non-contact and long-distance detection method with air-cou- pled antennas, is a fast nondestructive detecting technique in the field of structural health safety assessment of tunnels and underground engineering, which has changed the traditional measurement method of hand-held GPR antenna closely attached to the tunnel lining. This paper describes the detecting conditions and working principles of this technique used in health assessment of metro tunnels, and evaluates the feasibility of vehicle-mounted GPR to de- tect the metro tunnel in the basis of analyzing the test results. The experimental results show that this technique could detect the metro tunnel at normal operating speed within the vehicle gauge, providing a new method for the maintenance and safety inspection of operating metro tunnels. © 2018, Editorial Office of "Modern Tunnelling Technology". All right reserved.  相似文献   
76.
As the lack of guidancs for maintenance and repair of rail transit shield tunnels, this paper proposes a macroscopic method for grid assessment of shield tunnels. First, the tunnel serviceability index (TSI) is adopted as the tunnel condition assessment method and the results are compared with Chinese codes and the traditional fuzzy hierarchical comprehensive evaluation method. Second, based on the assumption that the factors affecting the conditions of the tunnels, such as the surrounding stratum environment, the structural overlying load and so on, are correlated spatially, the spatial variability theory is used for the grid assessment of shield tunnels. Finally, taking the Shanghai Rail Transit System as an example, the application results of the grid assessment method are described. © 2018, Editorial Office of "Modern Tunnelling Technology". All right reserved.  相似文献   
77.
The large settlements of tracks will emerge due to multiple disturbances in the construction of over- lapped shield tunnels, which affects the running safety of trains. Based on the overlapped Sungang station-Honghu station shield running tunnels of Shenzhen Metro line 7 passing underneath 26 tracks of high speed railways, a rein- forcement technology system consisting of”track support + subgrade reinforcement + interlayer soil consolidation + internal support of the lower tunnel”was developed. The settlements of tracks were mainly monitored automatically with manual monitoring as an auxiliary one. The results show that the maximum settlement of main track caused by constructing overlapped shield tunnels is -5.9 mm which is less than the control value of 10 mm, ensuring the opera- tion safety and verifying the reliability and practicability of the reinforcement technology system. © 2018, Editorial Office of "Modern Tunnelling Technology". All right reserved.  相似文献   
78.
79.
This "rutter for piracy" begins with a brief update on contemporary piratical incidents and a short review of books and collections of articles dedicated to the topic of piracy, before presenting the ground-breaking group of scholarly essays which make up WMU Journal of Maritime Affairs' special issue on piracy at sea.  相似文献   
80.
该文提出了基于军用互联网构建舰船电子设备远程维修系统的总体设计方案,并讨论了系统中关键模块的实现方法。该系统以信息的流动代替维修专家的流动,能够实现舰船电子设备远程故障诊断和维修,缩短维修时间、节约维修开支。  相似文献   
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