机械臂绝对定位精度测量

提出了用激光跟踪仪标定机械臂的D-H参数、测量机械臂绝对位姿以及对机械臂的绝对定位精度进行分析的方法;用激光跟踪仪测量机械臂各个关节单独运动时得到的一系列离散点,就可确定机械臂各个关节的轴线,由此建立机械臂的D-H坐标系,并对D-H参数进行标定;然后,给出了由6D激光头位姿确定机械臂末端位姿的方法;最后,推出了由测量位姿值与命令位姿值相比较,得到机械臂绝对定位的位置和姿态偏差的方法;这些方法可以有效、迅速地完成对机械臂绝对定位精度的测量.     

Complexity of families of learning algorithms and estimation of the nonrandomness of extraction of empirical regularities

The paper presents a general approach to the evaluation of the complexity of classes of algorithms, so-called pVCD-method. To develop this method, all the examined families of models of empiric generalization were restricted to classes implementable on computers and, wider, by examining their partially recursive representations. Within the framework of the algorithmic approach, the concept of Kolmogorov’ complexity of algorithms for the recognition of properties or the extraction of regularities is proposed. The method proposed to evaluate the nonrandomness of the extraction of empirical regularities is based on this concept.     

机车空调逆变电源设计

本文讨论的是机车空调逆变电源系统的设计与研究。该电源系统主要是由DC/DC的BOOST升压部分和DC/AC三相逆变部分两部分组成。DC/DC部分所得直流电压通过DC/AC部分逆变成三相交流电,供给空调机组工作。同时,为使电源系统能更可靠的运行,也设计了相应的故障检测、保护等辅助电路。     

Modifications of the method of variation of parameters

In spite of being a classical method for solving differential equations, the method of variation of parameters continues having a great interest in theoretical and practical applications, as in astrodynamics. In this paper we analyse this method providing some modifications and generalised theoretical results. Finally, we present an application to the determination of the ephemeris of an artificial satellite, showing the benefits of the method of variation of parameters for this kind of problems.     

神华集团数字矿山建设研究

探讨了数字矿山的内涵及特征、神华集团建设数字矿山的意义及目标,得出结论:数字矿山以面向矿山业务为依托,以数据互联互通为原则,以信息的整合、利用为核心,以矿山生产过程自动化为基础,以统一的传输网络平台为框架,以统一的软件平台为手段,以绿色开采技术、装备技术、信息技术为支撑,以标准体系为保障,其建设目标为"安全、绿色、智能、高效"。     

传输线信号完整性的反射分析

针对高速电路系统的传输线信号完整性问题,通过对高速电路PCB上传输线等效电路的分析,给出了信号传输时产生反射现象的原因;介绍了常用的消除反射的方法,即选择均匀传输线、采用合适的拓扑结构布线和阻抗匹配法,指出阻抗匹配法可解决信号传输的反射现象;阐述了源端阻抗匹配法和负载端阻抗匹配法消除反射的原理和适用条件。针对时钟电路中的反射问题,采用PADS/Hyperlynx软件对阻抗匹配法进行仿真,结果表明,阻抗匹配法能够改善信号传输的反射现象。     

A series of maximum subalgebras of direct products of algebras of finite-valued logics

We construct a series of maximum subalgebras of direct products of algebras of finite-valued logics, which are subdirect products of the corresponding Boolean algebras. We show that subdirect products make the largest contribution to the number of maximum subalgebras. The completeness problems is solved in the algebra of vector Boolean functions.Translated from Kibernetika No. 3, pp. 11–16, May–June, 1989.     

石油钻井泵阀体高频淬火温度的自动控制

针对石油钻井泵阀体高频淬火工艺要求，选用红外测温传感器测量石油钻井泵阀体的淬火温度，采用8031单片机自动控制温度，并可随时打印温度值，工件计数值，该系统控制精度高，抗干扰能力强，运行效果良好。     

Monte Carlo analysis of probability of inundation of Rome

Rome's monumental centre has often been inundated by Tiber River. In the last decades of the 19th century, river walls were erected to protect Rome from floods so that the last significant flood, which occurred in 1937, caused only marginal damages. Although the probability of inundation of the city seems to be now substantially reduced, the evaluation of the residual risk is still worthwhile. With this aim, rainfall, rainfall–runoff, river flood propagation and street flooding processes are simulated in detail to produce the inundation scenarios analysed by the Monte Carlo method. The study shows that severe floods, having a return period greater than 180 years, overtop both the left and right river banks and inundate the northern outskirts of Rome, while extreme events, with 1000 years return period, submerge large parts of the monumental centre of Rome.     

Analysis of microdensitometric data in terms of probability of cleavage of DNA

Computer-aided analysis of autoradiographic films of DNA fragments is presented. The Powell least-squares procedure is used for optimization of parameters for components of complex densitometric curves. Since each densitometric spectrum may be divided for several non-overlapped blocks of bands, there is no upper limit on the number of parameters which must be optimized. Eight shapes for the component bands are utilized: symmetric and asymmetric Gauss and Cauchy functions, direct, symmetric and asymmetric product of Gauss function and inverse of Cauchy function, and log-normal function. The probability of DNA cleavage is calculated with correction for multiple cuts. The methods presented was applied to detailed analysis of densitometric spectra of a 21-bp DNA restriction fragment and allowed for direct correlation between structural microheterogeneity of DNA and the resulting cutting pattern. This method should facilitate the analysis of densitometric data from antibiotic-induced cleavage of DNA and footprinting experiments.     

风电机组电动变桨距控制系统的优化研究

由于风速的随机性、不稳定性及气动效应的影响,使得风力发电机组变桨距控制系统具有非线性、参数时变性、强耦合等特点,难于实现高精度控制,导致风电机组输出电能质量较差。为了改善系统在恒功率输出运行区域内的动态性能,分析了风电机组变桨距控制系统的现状,建立了整个风电机组模型,提出了优化的变桨距控制策略,并设计了基于模糊控制的变桨距控制器。仿真结果表明,独立变桨距控制技术的控制效果比统一变桨距好,实现了风力机各叶片的优化独立变桨距控制,优化了风力发电系统在超过额定风速时的恒功率控制,具有抗干扰能力强、控制精度高的特点。     

联合收割机脱粒滚筒恒速智能控制器设计

研究了轴流式联合收割机的控制问题,给出了联合收割机脱粒滚筒的数学模型,介绍了基于模式识别的智能控制原理,建立了联合收割机脱粒滚筒恒速控制模型,设计了基于模式识别的智能恒速控制器.应用Matlab/Simulink进行了控制器仿真,其结果表明,将基于模式识别的智能控制应用于联合收割机脱粒滚筒的恒速控制,其过渡过程平稳、响应速度快、无超调、无振荡并且无稳态误差.     

支持向量机多类目标分类器的结构简化研究

由于支持向量机(SVM)在模式识别和回归分析中有着独特优势，因此成为近来研究的热点，其优势主要体现在处理非线性和高维数据问题方面。最初的SVM特别适合解决两类目标分类问题，而对于多类目标分类，则需将其转化为多个两类目标分类问题，相应地即可构造多个两类目标子分类器，但由于这种情况导致了分类器结构的过于复杂，从而导致判决速度的降低。为了快速地进行分类．提出了一种简化结构的多类目标分类器，其不仅使得子分类器数目大大减少，而且使分类速度明显提高；同时对其分类精度和复杂度进行了对比分析。实验结果证明。该分类器是有效的。     

物联网传感节点的无线供电技术研究

传统的物联网传感节点多采用电池供电,大大限制了传感器节点在更加恶劣的环境中工作的可靠性。同时,大量电池的使用和更换,既浪费了人力也给环境带来了污染。射频无线供电将使传感器节点彻底摆脱传统电池供电的种种束缚与弊端,通过高频信号输出、高频放大器、势垒稳压电路、动态释放电路等模块进行非接触式的微电量传输。本文分析了物联网以及无线供电在国内外的发展现状,并对以上各核心电路模块进行了设计与描述,最后总结了射频无线供电在物联网领域的应用前景。     

超大规模集成电路可调试性设计综述

随着硬件复杂度的不断提高和并行软件调试的需求不断增长,可调试性设计已经成为集成电路设计中的重要内容.一方面,仅靠传统的硅前验证已经无法保证现代超大规模复杂集成电路设计验证的质量,因此作为硅后验证重要支撑技术的可调试性设计日渐成为大规模集成电路设计领域的研究热点.另一方面,并行程序的调试非常困难,很多细微的bug无法直接用传统的单步、断点等方法进行调试,如果没有专门的硬件支持,需要耗费极大的人力和物力.全面分析了现有的可调试性设计,在此基础上归纳总结了可调试性设计技术的主要研究方向并介绍了各个方向的研究进展,深入探讨了可调试性结构设计研究中的热点问题及其产生根源,给出了可调试性结构设计领域的发展趋势.     

基于多DSP并行处理的发动机综合参数测试系统设计

为了实现发动机动态参数的综合测试、实时在线检测和故障诊断,综合考虑其通用性和专用性,提出了一种基于多DSP并行处理和虚拟仪器技术的新型发动机综合参数实时测试系统设计,重点阐述了系统的硬件结构和软件框架设计．并对系统实时、远程故障诊断进行了探讨。系统的实际应用,显著提高了测试精度和工程试验效率,同时也为发动机在线实时监测和故障诊断提供了可靠保障。     

《数据库系统概论》教学方法探索

针对<敷据库系统概论>课程的教学性质,结合其理论和实践教学并重的教学特点,对该门课程的本科生教学进行了探索.分析该门课程的体系结构和教学中存在的问题,给出了相应的解决办法,对该门课程的教学方法进行了研究、探索和总结.     

两种直方图规定化实现算法的分析

直方图规定化可以将图像的直方图转化为需要的形状,有目的地增加某个灰度区间的图像,使用户获得感兴趣的信息.本文介绍了直方图规定化的两种经典的实现算法--单映射规则(SML)和组映射规则(GML)的基本原理,并应用这两种算法对实例图像进行规定化处理和比较分析,证明了GML相对于SML的优越性.     

The computation of zones of influence of linear geological structures

The concept of a zone of influence of a linear geological structure provides a method of quantifying the effect of the structure on the properties of its neighborhood. For example, a fault may exert some influence on the local roof conditions in a mine opening, or on the location of mineral deposits, where the influence at any given distance (up to the specified half-width of the zone of influence) from the fault is estimated by some postulated influence function. Any area of interest may be partitioned into a large number of cells, and the sum of the influences due to the nearby faults calculated for the midpoint of each cell. The program groups the cells, by midpoints, into sets comprising those cells affected by precisely 0,1,2,... faults, calculates the proportion each set constitutes of the area of interest, and the total of the midpoint sums of the cells in each set. Although the program was developed for a specific problem in a New South Wales colliery, the method is not specific to this problem and has application to many situations in rock mechanics, metallogenesis, seismicity, and in other fields in which the concept of a zone of influence may be relevant.