1、5月 12日1、机器人同时定位与地图构建技术研究Research of simultaneous localization and mapping in robot【作者】柯文德; 蔡则苏; 李家兰【Author】 KE Wen-de1; 2; CAI Ze-su2; LI Jia-lan1 (1.Dept.of Computer Science; Maoming College; Maoming Guangdong 525000; China; 2.School of Computer Science; Harbin Institute of Technology; Harbin 15000
2、1; China)【作者机构】茂名学院计算机科学与技术系; 哈尔滨工业大学计算机科学与技术学院【摘要】 移动机器人同时定位与地图创建是实现未知环境下机器人自主导航的关键性技术,具有广泛的应用前景,也是目前机器人研究的热门课题之一。针对国内外近年来关于移动机器人同时定位与地图创建的研究工作进行了总结和分析,重点介绍了机器人的地图创建方法类别、基于概率理论的自主定位方法、同时定位与地图创建的问题描述及研究方法等方面的发展现状及存在的不足。【Abstract】 Simultaneous localization and mapping is the key technology to realize
3、 the auto navigation for robot in the unknown environment,which has been a particularly active topic of mobile robot due to its potential.This paper was a survey of the recent researches on such areas of SLAM as types of map construction,self localization based on probability,description of SLAM and
4、 its researching methods,etc.Raised some aspects in SLAM needed to be improved finally.【关键词】 机器人; 地图; 未知环境; 同时定位与地图创建【Key words】 robot; map; unknown environment; simultaneous localization and mapping2、延迟反馈法控制四阶混沌系统的解析研究Analytic study of controlling chaotic system with n=4 by delayed feedback【作者】王鹍【A
5、uthor】 WANG Kun(College of Information Science and Electronic Technology; Jiamusi University; Jiamusi 154007; China)【作者机构】佳木斯大学信息电子技术学院【摘要】 以一个新型四阶混沌系统为例,研究延迟反馈消除四阶系统混沌的方法.利用分析延迟系统产生 Hopf分支条件的方法,给出控制参数的一般解析关系.仿真实验表明,在由解析分析得到的控制条件下,混沌系统的不稳定周期轨道被稳定到平衡点,验证了这种控制方法的有效性.【Abstract】 Delayed feedback method
6、was studied to deal with chaos elimination in a new chaotic system with n=4.Via the analysis of emerging Hopf bifurcation of delay system.A general analytical relationship of control parameters was given in this paper.Simulation results showed that the unstable orbits of chaotic system can be stabil
7、ized to equilibrium point under the control conditions from analytic analysis,and demonstrate the effectiveness of the proposed control approach.【关键词】 混沌控制; 延迟反馈; Hopf分支【Key words】 Chaos control; delayed feedback; Hopf bifurcation3、矩阵式变换器的输入功率因数控制Input power factor control for matrix converters【作者】梅
8、杨; 孙凯; 黄立培【Author】 MEI Yang1; 2; SUN Kai1; HUANG Lipei1(1.State Key Laboratory of Control and Simulation of Power Systems and Generation Equipment; Department of Electrical Engineering; Tsinghua University; Beijing 100084; China; 2.Field Bus Technique and Automation Key Laboratory; North China Unive
9、rsity of Technology; Beijing 100041; China)【作者机构】清华大学电机工程与应用电子技术系电力系统及大型发电设备安全控制和仿真国家重点实验室; 北方工业大学现场总线及自动化北京市重点实验室【摘要】 矩阵式变换器输入滤波器会引起滤波前后电流基频分量的相位差,降低矩阵式变换器的输入功率因数。为了保证其输入功率因数始终接近1,以减小对电网的不利影响,提出了一种自适应控制方法。根据输入电压和电流值计算输入滤波器前后的电流相位差,并据此实时调节输入相移角的设定值,实现在任意工况下对输入功率因数的有效控制。在一台基于逆阻式 IGBT(RB-IGBT)的矩阵式变换器驱
10、动异步电机调速系统样机上进行了实验测试。在不同负载情况下,采用该方法均有效减小了输入功率因数角,使输入功率因数始终接近于1,从而改善了矩阵式变换器的输入性能。【Abstract】 A matrix converter(MC) input filter introduces a phase difference between the input current before and after the filter,which directly influences the MC input power factor.An adaptive input power factor control
11、 method was developed to maintain a unity input power factor and reduce the negative influences on the power grid.Measurements of the input voltage and current can be used to adjust the displacement angle in real time to modify the input power factor at the grid side for any load condition.Tests on
12、a RB-IGBT based MC fed induction motor drive prototype demonstrate that the input power factor angle is reduced and matrix converter input power factor is maintained at unity by this control method.【关键词】 矩阵式变换器; 相位角; 输入功率因数; 控制【Key words】 matrix converter(MC); phase angle; input power factor; contro
13、l4、用于电阻抗谱测量的脉冲式方法的研究Research on a Pulsed Approach for Electrical Impedance Spectroscopy Measurement【作者】董恩生; 董永贵; 孙国强; 吕文尔; 潘海洋【Author】 DONG Ensheng1 DONG Yonggui2 SUN Guoqiang1 L Wener3 PAN Haiyang1 (1. Department of the Aviation Control and Engineering; Aviation University of Air Force; Changchun 1
14、30022; 2. Department of Precision Instruments and Mechanology; Tsinghua University; Beijing 100084; 3. Health Science and Technology Division; Massachusetts Institute of Technology; MA 2139; USA)【作者机构】空军航空大学航空控制工程系; 清华大学精密仪器及机械学系; 麻省理工学院健康科学与技术系【摘要】 为了将电阻抗谱应用于复合材料构件的异常检测,针对被测对象电阻抗谱的测量,提出一种不同于传统扫频方式的
15、脉冲式方法。采用软/硬件协同设计方法设计并实现基于现场可编程门阵列(Field programmable gate array,FPGA)的脉冲式检测系统。该系统能产生频率和脉宽可调的方波脉冲作为敏感电极的激励信号,基于 FPGA芯片实现了一种能对瞬态响应电流曲线进行高速采集的步进采样方法,对采集到的电流曲线作进一步的处理以获得被测对象的电阻抗谱。为了验证脉冲式检测系统用于电阻抗谱测量的可行性和有效性,对 Randles单元模型及双弛豫时间等效电路模型电阻抗谱的测量进行试验研究,并与理论计算得到的电阻抗谱进行了对比分析。初步的试验结果表明,脉冲式检测系统能有效地提取被测对象的电阻抗谱信息,所提
16、出的方法用于测量被测对象的电阻抗谱是可行的和有效的。【Abstract】 For the application of electrical impedance spectroscopy to the anomaly detection of composite material component, a pulsed method for impedance spectroscopy measurement, different from the traditional swept frequency methods, is presented. A string of square-wav
17、e pulses is digitally generated as the exciting signal to the sensing electrodes. A step sampling method for collecting the instantaneous response current curves is realized on the basis of a field programmable gate array (FPGA) chip. The collected curves are further processed to obtain the impedanc
18、e spectroscopy. Experiments are carried out for the measurement of electrical impedance spectroscopy of the demo electric circuits in order to verify the feasibility and practicability validity of the pulsed measurement system. The preliminary experimental results indicate that the pulsed measuremen
19、t system can effectively extract the electrical impedance spectroscopy information of the detected object. The proposed approach is feasible and practicable for evaluating the electrical impedance spectroscopy of the detected object.【关键词】 电阻抗谱; 脉冲式检测系统; 脉冲激励; 现场可编程门阵列; 电阻抗模型【Key words】 Electrical im
20、pedance spectroscopy Pulsed measurement system Pulse excitation Field programmable gate array Electrical impedance model5、就业与我国大学应届毕业生焦虑和抑郁的关系Employment-related anxiety and depression in senior college students in China【作者】彭敏宁; 胡国清; 董晶; 张玲玲; 刘彬彬; 孙振球【Author】 PENG Minning1; 2; HU Guoqing1; DONG Jing1
21、; ZHANG Lingling3; LIU Binbin1; SUN Zhenqiu1(1.Department of Epidemiology and Health Statistics; School of Public Health; Central South University; Changsha 410078; China; 2.Central South University Press; Changsha 410083; China; 3.Department of Population and International Health; Harvard School of
22、 Public Health; Boston 02115; USA)【作者机构】中南大学公共卫生学院流行病与卫生统计学系; 中南大学出版社; 哈佛大学公共卫生学院人口与国际卫生学系【摘要】 目的:探讨大学应届毕业生就业相关事件与抑郁和焦虑的关系。方法:采用横断面研究对1321名来自中南大学的应届毕业生进行匿名调查。采用自评焦虑量表(SAS)和美国 CDC编制的流行病学调查用抑郁量表(CES-D)分别评价焦虑和抑郁情况。就业相关事件采用被调查时学生面临的就业选择来反映。采用 logistic回归分析就业相关事件对焦虑和抑郁的影响。结果:收到有效问卷1178份。以50分和16分分别作为 SAS和
23、CES-D的判断临界值时,分别有18.9%和55.4%出现了焦虑和抑郁。控制其他因素后,考研且感觉良好、考研但感觉不是很好以及既未考研又目前没工作意向的学生出现焦虑的风险分别是直接保研且确定读研学生的2.5,2.3和3.5倍(P0.05);上述3类学生出现抑郁的风险分别是直接保研且确定读研学生的2.0,1.5和2.6倍(P0.05)。结论:就业意向较差的大学应届毕业生出现焦虑和抑郁的风险高于就业意向较好的学生。【Abstract】 Objective To examine the association of employment-related events with depression
24、and anxiety in senior college students in China.Methods Altogether 1321 senior college students were recruited from Central South University and the survey was administered anonymously.Anxiety and depression were assessed with the Self-rating Anxiety Scale(SAS)and the Center for Epidemiologic Studie
25、s Depression Scale(CES-D),respectively.Employment-related events were reflected by the employment-related options when students were surveyed.Logistic regression was used to estimate the effect of employment-related events on anxiety and depression.Results We collected 1178 valid questionnaires.Taki
26、ng 50 and 16 as the cutting-point of SAS and CES-D,we found 18.9% and 55.4% of the participants showed symptoms of anxiety and depression,respectively.After controlling confounding factors,those students who had taken the entrance exam of graduate schools and were optimistic for the result,those who
27、 had taken the entrance exam of graduate schools but were pessimistic for the result,and those who neither took the entrance exam of graduate schools nor received a job offer,had a higher risk of anxiety than those who would attend a graduate school without exam,and the odds ratios were 2.5,2.3,and
28、3.5,respectively.For students depression,the odds ratios of the three categories mentioned above were 2.0,1.5,and 2.6,respectively.Conclusion Senior college students who face bad employment-related events are at a higher risk of anxiety and depression.【关键词】 就业; 抑郁; 焦虑; 大学应届毕业生; 中国【Key words】 employm
29、ent; depression; anxiety; senior college students; China5月 15日1、开环零点、极点的位置，决定了根轨迹的形状。Open-loop zero, pole position, determine the shape of root locus.2、开环和闭环的基本差异是可连续或断续的反馈作用。Open and closed loop of fundamental differences between continuous or intermittent feedback.3、系统的稳、准、快，由闭环传递函数的极点，稳态误差，动态指标来控
30、制。System of steady,accurate,fast,by the poles of the closed-loop transfer function,steady-state error, dynamic index to control.4、比例控制，K 增大时,稳态误差终值减小，相角裕度降低，剪切频率增加，调节时间减少，动态性能变好。Proportional control,when K increases, the steady-state error of the final value lower,phase margin decrease, cut the freq
31、uency increased,reduce the settling time, changed for the better dynamic performance.5月 17日、5 月 19日根轨迹法The Root-Locus Method艾久超Ai Jiuchao（佳木斯大学信息电子技术学院）（ College of Information Science and Electronic Technology; Jiamusi University; Jiamusi 154007; China)【摘要】系统的稳定性完全由它的特征根所决定，而特征方程的根又与系统参数密切相关。那么如果系统
32、中某个参数发生变化，特征方程的根会怎样变化，系统的稳定性又会怎样变化？当特征方程阶次高时，手工求解方程相当繁琐。1948年，伊文思（W.R.Evans）提出一种求闭环系统特征根的简便图解法。它的主要内容是，当系统的某一参数变化时，利用已知的开环传递函数的极点和零点，依照一些简单的规则，用作图的方法绘制闭环系统的特征根的轨迹。根轨迹法比满了复杂的数学计算，因此是分析控制系统的简单方法。【Abstract】Stability of the system is entirely determined by its characteristic roots, while the characteris
33、tic equation has roots with the system parameters. So if the system changes in a parameter, the root of the characteristic equation will be how changes in the stability of the system what will change? When the high order of the characteristic equation, solving equations by hand rather cumbersome. In
34、 1948, Evans (W.R.Evans) proposed a closed-loop system eigenvalue seeking simple graphic method. Its main content is that when the system changes a parameter, using the known open-loop transfer function poles and zeros, according to some simple rules for closed-loop system for drawing graphs of the characteristic roots of the track. Root locus method than the full complex mathematical calculations, it is a simple method of control system.【关键词】系统参数；特征根；根轨迹；稳定性【Key words】system parameters；characteristic root; root locus; stability
