排序方式: 共有101条查询结果,搜索用时 31 毫秒
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针对舰艇、轮船等经常处于低频圆锥运动、角机动等恶劣工作环境,传统姿态更新的误差补偿方法在多子样更新中补偿效果较差的问题,提出了一种改进方法。通过建立角增量的2N-2阶近似模型并利用其各阶导数之间的解析关系,实现了对等效旋转矢量的进一步修正。使用参数解析法与改进算法分别推导研究了四子样情况下的优化结果,并分析研究了改进算法在四子样以上情况下的适用性。研究表明,与参数解析法相比,改进算法可以在四子样及四子样以上的情况下简单直观地得到更加精准的优化系数,且与四子样参数解析法相比,其误差缩小了2个数量级,同时也比五子样参数解析法更精确。 相似文献
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用不求导数的最优化计算可靠度指标 总被引:10,自引:1,他引:9
本文从线性极限状态函数下独立正态分布变量的可靠度指标声的几何涵义出发,运
用最优化计算原理,提出了不用导数计算声和设计验算点的优化分析方法。文中用改
进Powcll法研制的计算程序,避免了大多数可靠度分析法有时甚繁的求导数工作。通
过对多个工程实例的可靠度分析表明,该方法使用方便、收敛快,计算精度不低于国
际结构安全度联合委员会(Jc5s)推荐采用的“Jc”法. 相似文献
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A rapid path planner for autonomous ground vehicle using section collision detection 总被引:1,自引:0,他引:1
Rapid path planner plays an important role in autonomous ground vehicle (AGV) operation. Depending on the non-holonomic kinematics
constraints of AGV, its path planning problem is discussed. Since rapidly-exploring random tree (RRT) can directly take non-holonomic
constraints into consideration, it is selected to solve this problem. By applying extra constraints on the movement, the generation
of new configuration in RRT algorithm is simplified and accelerated. With section collision detection method applied, collision
detection within the planer becomes more accurate and efficient. Then a new path planner is developed. This method complies
with the non-holonomic constraints, avoids obstacles effectively and can be rapidly carried out while the vehicle is running.
Simulation shows that this path planner can complete path planning in less than 0.5 s for a 170 m×170 m area with moderate
obstacle complexity.
相似文献
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搭载自动驾驶功能的智能网联汽车因可在其设计运行条件内承担全部动态驾驶任务,面临安全验证与评估挑战。基于场景的智能网联汽车安全测试评估方法已成为广泛的行业共识,模拟仿真测试是其重要手段之一。从第三方视角,针对自动驾驶安全性、高场景覆盖度、逻辑完备性等测试验证目标,搭建基于软件在环的模拟仿真测试环境框架,在此基础上研究基于设计运行条件覆盖的测试场景集构建方法,探索形成一套高可信智能网联汽车模拟仿真测试评估方法,并在特定应用场景进行初步实践。研究成果为模拟仿真测试在智能网联汽车安全测试与评估中的落地应用提供了参考。 相似文献
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This paper seeks to develop a multi-commodity network model to analyse the flow of containers within the Asia Pacific context. The model is used to evaluate the impact of container throughput in Asia's port by varying terminal handling charges and turnaround time. The three main regions analysed are north-east Asia, east Asia (Chinese port region) and south east Asia. Using the model, it could be shown that Busan port, which is an important transhipment hub in north-east Asia, could boost the container activities in the north-eastern part of China by improving its service quality. It is also found that the efficiency of the land link between Hong Kong and mainland China plays a crucial role for the future of Hong Kong port. While Singapore port maintains its position as a transhipment hub in south-east Asia, there would be expected competition from neighbouring low costs ports. 相似文献