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101.
通过对一种同轴并联式混合动力城市客车总成选型匹配及整车控制策略制定等研发活动的分析,提出一种同轴并联式混合动力城市客车的设计方法。 相似文献
102.
Micro incision vitrectomy system (MIVS) is considered to be one of the most difficult tasks of eye surgery,due to its requirements of high accuracy and delicate operation under blurred vision environment.There-fore,robot-assisted ophthalmic surgery is a potential and efficient solution.Based on that consideration,a novel master-slave system for vitreoretinal surgery is realized.A 4-DOF remote center of motion (RCM) mechanism with a novel linear stage and end-effector is designed and the master-slave control system is implemented.The forward and inverse kinematics are analyzed for the controller implementation.Then,algorithms with motion scaling are also integrated into the control architecture for the purpose to enhance the surgeon's operation accu-racy.Finally,experiments on an eye model are conducted.The results show that the eye robotic system can fulfill surgeon's motion following and simulate operation of vitrectomy,demonstrating the feasibility of this system. 相似文献
103.
为了求解面向制造领域物料配送和废旧产品回收的同时送取货的车辆路径优化问题(VRPSDP),提出一种主从式并行模拟退火算法代替传统的串行模拟退火算法.算法首先使用剩余承载力和径向附加费(RCRS)算法求得初始解,然后在并行模拟退火算法框架下使用4种邻域搜索方法对初始解进行优化.最后,选取国际上通用的Montane和Galvao测试数据集(18个顾客数为100~400的测试问题)对算法性能进行测试,与文献中其他5种算法的比较显示,提出的并行模拟退火算法总体性能较优. 相似文献
104.
In this paper, we analyze the physical layer abstraction for bit interleaved coded orthogonal frequency division multiplexing (BIC-OFDM) system from a parallel bit channel perspective. By combining the exponential effective SNR (signal-to-noise ratio) mapping (EESM) with the maximum a posteriori (MAP) algorithm, a bit LLR (log-likelihood ratio) wise EESM (BL-EESM) method is proposed. This method can abstract the link performance with high accuracy, especially for the case when channel estimation is imperfect. Afterward, the BL-EESM method is simplified by utilizing the non-linear quantization idea, which can reduce the times of exponential operation by two orders of magnitude at wide system bandwidth, yet shows little loss in accuracy. Our proposal can be applied to both system level simulations to save the time consumption and to practical terminals to facilitate the adaptive modulation and coding (AMC) procedure, bringing about throughput improvement at low hardware cost. 相似文献
105.
106.
近年来,柱管接管相贯线接缝焊割由传统的手工焊逐渐被焊割机器人操作所代替。本文建立了圆锥、球体与柱管相贯线的一般化数学模型,并将空间相贯线展成平面曲线,利用等步长原理获取焊割轨迹的路径点。为保证焊割精度,步长的数值由输入的允许插补误差值经计算获得。文中还给出了柱管相贯线获取焊割路径点的流程图。此方法方便了焊割程序的编制,提高了工作效率,同时又保证了焊割的平稳性和精确性。最后给出了一个常见的柱管相贯实例,利用Matlab软件编程得到了其相贯线焊割路径点。 相似文献
107.
通过数学建模分析阻抗分配对电流转移过程的影响,并通过Ansoft仿真软件仿真两种并联真空断路器结构的电流分配、电动力以及温升情况,为并联真空断路器断口结构优化设计提供理论支持和技术依据. 相似文献
108.
Fuel economy comparison of conventional drive trains series and parallel hybrid electric step vans 总被引:1,自引:0,他引:1
S. B. Han Y. H. Chang Y. J. Chung E. Y. Lee B. Suh A. Frank 《International Journal of Automotive Technology》2009,10(2):235-240
A hybrid electric vehicle (HEV) is a vehicle that combines a conventional propulsion system with an on-board rechargeable
energy storage system to achieve better fuel economy than a conventional vehicle HEVs do not have limited ranges like battery
electric vehicles, which use batteries charged by an external source. The different propulsion power systems may have common
subsystems or components. The objective of this study is to compare the fuel economies of a conventional step van, a series
hybrid electric step van (HESV), and a parallel HESV by calculating the fuel consumption using the ADVISOR software by NREL.
We also showed the results of the vehicles in different driving cycles including the Central Business District bus cycles,
the New York City Cycle, and the US EPA City and Highway cycles. 相似文献
109.
110.
IntroductionIt is very important to master the locomotionprinciple of a micro piezoelectric actuator for peo-ple to design a micro piezoelectric actuator or arobot. so far,experimental method has been theonly approach available to design a micro piezoelec-tric actuator or a robot[1~ 4 ] .As a result,itis diffi-cult to make a parameterized design or an optimaldesign for a micro piezoelectric robot. Therefore,it is in dire need to constitute the locomotion equa-tion of the robot. In the paper,t… 相似文献