月球车视觉系统的一种匹配算法

针对月球车立体视觉系统对匹配速度和准确度要求较高的特点，提出了一种基于特征约束的区域匹配算法。该算法用多尺度小波变换实现边缘提取和降噪，采用多特征匹配、双向匹配、部分二次采样、选取图像子集等技术保证匹配的速度和精度。最后对匹配结果进行滤波，进一步提高匹配的准确性。     

Ambiguity resolution performance with GPS and BeiDou for LEO formation flying

The evolving BeiDou Navigation Satellite System constellation brings new opportunities for high-precision applications. In this contribution the focus will be on one such application, namely precise and instantaneous relative navigation of a formation of LEO satellites. The aim is to assess the ambiguity resolution performance with the future GPS and BeiDou constellations depending on system choice (GPS, BeiDou, or GPS+BeiDou), single- or dual-frequency observations, receiver noise, and uncertainties in ionosphere modelling. In addition, for the GPS+BeiDou constellation it will be shown how the growing BeiDou constellation in the years to come can already bring an important performance improvement compared to the GPS-only case. The performance will be assessed based on the percentage of time that the required precision can be obtained with a partial ambiguity resolution strategy.     

充水式潜水电机转子水磨耗的计算方法

充水式潜水电机转子水磨耗占电机机械损耗的绝大部分,但至今还没有比较简单实用的计算方法。在理论分析和大量试验的基础上,找出了影响转子水磨耗的主要因素,研究、总结了比较实用的转子水磨耗的计算方法并在设计和生产中得到了验证和应用。     

Effect of system response on partial surge initiated instability in a transonic axial flow compressor

Partial surge is a type of instability inception in transonic compressors and occurs in the form of axisymmetric low-frequency disturbances localized in the hub region. Previous studies illustrate that the frequency of partial surge is set by the Helmholtz frequency of the entire system,which motivates to propose a hypothesis that the system response performs an important role in the formation of partial surge. For further verification, a series of experiments are conducted to explore the link b...     

航空发动机滑油颗粒监测与控制标准研究

在航空发动机零部件的加工、装配及发动机工厂试车和检验试车过程中,运用先进的技术手段,开展以发动机零部件清洁度控制、装配清洁度控制及试车阶段滑油磨粒的监测试验,探索滑油中污染物的来源、污染程度及其对发动机使用的影响,确定磨粒来源、产生原因及典型故障模式,提出减少、控制污染物及磨粒的改进意见,进而制定出发动机滑油颗粒监测与控制标准,并应用于发动机生产及零部件的质量控制,对改进产品质量,降低生产成本,缩短生产周期等具有重要意义。     

基于接触状态的叶冠预扭设计和磨损分析

接触状态包括接触形式和接触参数,通过接触形式可从结构上判断结构设计的合理性．通过接触参数可从力学性能上评价叶冠的阻尼效果。接触状态能够细致地反映出叶冠工作状态下真实的接触情况．为叶冠结构设计和阻尼效果判定提供更准确、详尽的参考依据。本文针对某工程实际问题,建立了叶片三维分析模型,应用谐波平衡法和时频转换法分析了叶冠结构参数与安装状态下叶冠力学性能的关系,总结了叶冠几何参数对接触状态的影响规律。本文还进一步就叶冠接触状态与叶冠磨损之间的关系进行了讨论,最后基于接触状态的设计理论,提出了叶冠预扭设计的指导思想和工程方法。     

Spiking-free HGO-based DSC for flexible joint manipulator

The tracking control problem for Flexible Joint Manipulator Control System(FJMCS)with unmeasurable states is addressed in this paper. Firstly, a High-Gain Observer(HGO) is constructed to estimate the unmeasurable states and the uncertainties. Then, a Dynamic Surface Control(DSC) scheme is developed by using the estimation of HGO. The newly proposed controller has two advantages over the existing methods:(A) a novel Spike Suppression Function(SSF) is developed to avoid the estimation spike proble...     

粒子分离器叶片涂层冲蚀磨损的数值模拟

以叶片涂层为对象,研究其冲蚀过程中损伤的演化过程.首先进行了流场计算.其次通过对单个固体颗粒冲蚀过程的模拟,提出了"碰撞有效影响区域"的概念,使得多个固体颗粒连续冲蚀数值模拟得以实现.接下来通过模拟"碰撞有效影响区域"内材料受到固体颗粒连续冲蚀的过程获得材料的抗冲蚀磨损性能.最后,将流场数据和涂层抗冲蚀磨损性能参数相结合来模拟叶片涂层的冲蚀过程,指出了涂层的薄弱区域并进行了寿命预测.      

改进的相似度算法在复合材料构件成型工艺检索中的应用

对比传统的局部相似度的计算方法,指出了其局限性,在考虑了生产实际情况中可能出现的几种情况后,提出了不同属性局部相似度计算的方法,使其能解决复合材料构件成型工艺系统中相似实例检索的问题,系统检索结果符合实际生产情况,表明了该方法在复合材料构件成型工艺相似实例检索中应用的可行性和准确性.     

C语言常见错误

C语言是一种功能应用比较广泛的高级语言，作为教学语言非常方便，实用。