搜索双安全边缘点的实时路径规划方法研究

针对未知不确定性环境下机器人路径规划的特点,提出了基于搜索双安全边缘点的实时路径规划新方法.该方法从有限的实时环境信息中搜索躲避障碍物和保证机器人到达目标点的双安全边缘点信息,并结合启发式算法,实现了基于双安全边缘点的实时路径规划.机器人的实际工作环境是十分复杂的,要求路径规划算法有较高的适应能力,特别在u型环境中要求算法能够脱离死区.仿真实验在2种U型环境和复杂环境中进行,仿真结果表明,该方法具有反应灵敏、实时性好的特点,对不确定环境具有良好的适应性,能够实现未知复杂环境下的路径规划.     

Mathematical models of grinding manufacture and tooth contact analysis of spherical gears

The spherical gear is a gear-driven mechanism with two degrees of freedom (DOF), which can transfer spatial motion and power. Grinding machining of the spherical gear is performed with a plate grinding wheel by using generating method, and based on mathematical model of the plate grinding wheel, the mathematical model of the spherical gear is set up. And then, the meshing model of a spherical gear pair is developed and the tooth contact analysis (TCA) of the spherical gear pairs is performed. After that, th...     

Hopfield神经网络在机器人路径规划中的应用

将Hopfield反馈型神经网络方法,应用于对机器人工作路径的合理规划中,解决了对两两给定通路的若干工作站点,机器人能顺序访问并最终返回起点的最短巡游路径问题。可针对不同的具体问题来设计网络的连接权及能量函数。对8站点和16站点仿真结果表明,此方法可以在较短的时间内寻优获得最佳工作路径。     

基于应用层流量优化的中继路径选择方案

基于网络层路由协议的缺省单一路径难以满足高带宽应用的端到端传输需求,多径传输是一种有效方式。在基于应用层中继的多径传输系统的基础上,提出基于应用层流量优化的中继路径选择方案：借助于应用层流量优化机制,提出中继路径选择过程中遵循的规则,提出基于运营商定义域的最优中继路径生成算法,为数据传输分配优质的中继路径,同时在运营商定义域之间以及中继服务转发器之间保持负载均衡。仿真结果表明,提出的方案在选择优质中继路径方面具有较优性能,同时能够灵活地均衡运营商定义域之间的负载。     

基于双层模糊逻辑的多机器人路径规划与避碰

针对无通信情况下的多机器人系统在未知动态环境下的路径规划问题,设计了基于双层模糊逻辑的多机器人路径规划与动态避碰系统。方向模糊控制器充分考虑了障碍物的距离信息和目标的角度信息,转化为机器人与障碍物的碰撞可能性,从而输出转向角度实现机器人的动态避障;速度模糊控制器将障碍物的距离信息作为输入,将速度因子作为输出,提高了多机器人路径规划与动态避碰系统的效率和鲁棒性。在Pioneer3-DX机器人实体上验证了该系统的可行性。     

Profiling selected paths with loops

Path profiling records the frequency of each path in an executed program.To accomplish profiling,probes are instrumented in the program and executed as the program runs.So,the number of probes has a significant impact on the efficiency of a profiling technique.By profiling only the interesting paths,existing techniques try to improve the profiling efficiency by reducing the number of probes and optimize path encodings for efficient storage.However,they lack accuracy,waste time on running uninteresting paths,and can mainly deal with acyclic paths.In this article,a novel technique called Profiling Selected Paths(PSP)is introduced to profile selected paths,which enables custom selection for both acyclic and cyclic paths and increases the execution efficiency by early termination on uninteresting paths.Theoretical analysis and experimental evaluation indicate that PSP performs better than existing techniques.     

Solid/liquid extraction and isolation by molecular distillation of hydroxytyrosol from Olea europaea L. leaves

Molecular distillation, or short‐path distillation (SPD), is particularly appropriate for processing of low‐volatility compounds, which are easily altered at high temperature. Olea europaea L. leaves constitute an olive tree by‐product very interesting for their natural antioxidants content. In this research, molecular distillation technology has been applied to obtain high‐value‐added compounds by the SPD fractionation of an olive tree leaf extract. The process consists of two stages: (a) ethanolic extraction of the olive leaves, followed by incorporation of the extract into glycerine and (b) molecular distillation of the glycerine enriched in olive leaf extract compounds (terpenic and phenolic compounds). Four molecular distillation tests under different conditions were carried out. Results showed that 80.9% 3,4‐dihydroxy‐phenylethanol (hydroxytyrosol) was recovered from the glycerine admixture under a pressure of 1.50–2.00 mbar, a temperature of 190 °C and a feed rate of 15 mL/min.     

社会资本支持矿产资源勘查开发的路径与举措

文章剖析了中国矿产资源勘查开发面临的战略机遇和风险挑战,从行业运行规律、宏观管理政策、资本市场发展等方面分析了资本支持矿产资源勘查存在的突出问题,在此基础上,提出了新形势下资本市场支持中国矿产资源勘查、助力国家资源安全的思路框架和路径举措：（1）统筹谋划,为社会资本支持矿产资源勘查开发提供战略指引。（2）改革创新,持续打造更加良好的矿业发展营商环境。（3）试点先行,建立完善以中国特色风险勘查资本市场为核心的多层次矿业资本市场。（4）银企联动,创新完善矿产资源勘查开发间接融资支持体系。（5）精心培育,弘扬企业家精神,加快建设风险勘查经营主体。（6）扩大开放,建立更高水平开放型勘查开采新体制。（7）综合保障,加快完善矿产资源勘查开发综合服务体系。     

新能源汽车低频振动噪声传递路径模拟方法

针对新能源汽车低频噪声分布规律具有复杂性,造成噪声传递路径模拟难度加大等问题,提出新能源汽车低频振动噪声传递路径模拟方法。定义声阻与声抗以明确材料声学特征,以此为基础建立新能源汽车低频振动方程。分析低频振动噪声传递路径,使用力锤激励法测量传递函数,同时采用悬置刚度方法测量激励力,分析噪声激励响应,并修正噪声响应系数。计算有效点导纳,分别获取每个噪声在对应传递路径上的贡献量,确定噪声分布规律,实现噪声传递路径模拟。仿真结果表明,所提方法噪声估计精准度高,模拟时间短,模拟准确率高,能够为汽车降噪提供重要参考。     

基于蚁群算法的三峡升船机船厢设备巡视点检路线规划

针对三峡升船机船厢结构复杂,设备巡视路线难以选择的问题,以升船机船厢巡视路线为研究对象,将设备巡视点检路线规划转换为TSP旅行商问题.通过巡视路线无向加权图及点位空间坐标,建立升船机设备巡视点检点位空间结构模型.结合蚁群算法在Matlab软件中分别计算出白班及中班的最佳巡视路线.实验结果表明,基于蚁群算法计算的最佳巡视路线符合三峡升船机设备巡视要求.