组织变革中员工创新行为影响机制研究——以责任导向为调节变量

世界经济环境日趋复杂,企业竞争也愈加激烈,因此,变革已成为企业更好地生存和可持续发展的必然手段。对45家变革企业员工及其直属领导的访谈和实证研究表明,工作不安全感对员工创新行为有负面影响,变革情感承诺在其中起到了中介作用,员工的任务责任导向在员工变革情感承诺和员工创新行为之间起到了调节作用。国家自然科学基金项目(71402153

Control on model attitude and oscillation by wire-driven parallel manipulator support system for low-speed wind tunnel

介绍了基于机器人技术的绳牵引并联机构的特点;设计并建造了适用于低速风洞试验的八绳六自由度绳牵引并联支撑机构样机(WDPSS-8),给出其具体的结构参数,分析了该机构的特点及可行性;建立了该系统的运动学位姿逆解模型和静力学模型,完成了运动学逆解的推导,得到已知缩比模型位姿求绳长变化的公式;搭建了相应的绳牵引并联机构的控制实验平台,在此基础上进行了静力学工作空间的分析,通过Matlab编程仿真得到了缩比模型在主位姿处3个姿态角的工作空间;并在此实验平台上进行了缩比模型的三转动自由度姿态变化运动控制,实现了缩比模型运动到指定角度的控制;在此基础上按指定振幅和频率进行了三转动单自由度振荡的运动控制;对运动控制试验结果进行了初步的误差分析。A 6-DOF WDPSS-8(WDPSS:Wire-Driven Parallel Suspension System)suitable to low-speed wind tunnel was designed.The structural parameter of the system was given.The feasibility of the WDPSS-8 has been analyzed.The inverse kinematics position model and statics model have been set up.The solutions to the inverse kinematics problem and the formula of the wire length variation have been deducted.The prototype of the WDPSS-8 was manufactured.The workspace of the scale model attitude in main position has been simulated with a Matlab programming.The attitude control has been accomplished and the appointed attitude angle of the model can be achieved on the demand.Based on the work mentioned above,oscillation control experiment in three freedoms has been carried out respectively according to required amplitude and frequency.At last the error analysis of the system has been made.国家自然科学基金(50475099)资助;; 福建省青年人才创新基金(2006F3083)资

Overview of Wire-driven Parallel Kinematic Manipulators for Aircraft Wind Tunnels

【中文文摘】首先概述了法国航空局SACSO项目关于绳牵引并联机构应用于飞行器风洞试验的研究工作,然后从六自由度绳牵引并联机构的结构设计、运动学及性能分析、工作空间的分析与综合、静刚度分析、运动控制和力控制等六方面,详细分析了六自由度绳牵引并联机构应用于飞行器风洞试验中的关键技术。分析结果表明:六自由度绳牵引并联机构必须根据飞行器的类型,以工作空间大小为依据进行构型设计;其运动控制方案可借用PID控制或自适应控制,其优点是便于动力学模型的线性化和解耦;其力控制方案可借用经典的阻抗控制和力/位置混合控制,但适用于飞行器风洞试验的六自由度绳牵引并联机构的更完善的力控制策略还有待进一步的研究。 【英文文摘】First, an overview of the research work on the SACSO project at ONERA in France is presented, and then the key issues of six DOFs wire-driven PKMs for aircraft wind tunnels are addressed.And the key issues are focused on structural design,kinematics analysis,workspace analysis and synthesis,static stiffness analysis,motion control scheme,and force control scheme.The results demonstrate that the structure of a wire-driven PKM should be based on the aircraft model and its workspace volume.The PID and self-ada..

Kinematic analysis of a wire-driven parallel manipulator with 1R2T type on upright position

设计了立面1R2T三自由度绳牵引并联机构的模型.在竖直平面上对末端执行器模型进行了速度、加速度运动学分析,包括速度、加速度运动学逆解.用力矩平衡法确定其质心位置,对位姿运动学模型进行了一阶、二阶求导,得出了运动学速度、加速度逆解模型.根据封闭矢量三角形法则,求出了速度运动学逆解模型,给出了运动学速度逆解Jacobian矩阵.在规划的椭圆轨迹下,采用Simulink仿真软件进行了末端执行器质心的速度、加速度和绳速度变化规律的仿真,并搭建了控制系统的硬件设备.研究表明,在所规划椭圆轨迹下,所有绳速度、加速度的变化是连续的且求解速度、加速度逆解的算法正确、通用.A kind of 3-DOF wire-driven parallel manipulator with 1R2T type is designed.The kinematical analysis on the velocity and acceleration of its end effector is given on the upright position according to the manipulator.The centroid position of the effector is determined by moment balance principle.The inverse solution of both velocity and acceleration kinematics has got through first and second derivative of the position kinematics.The principle of closed vector triangle is applied when deriving the inverse solution of velocity kinematics.In the meantime,Jacobian Matrix of inverse solution of velocity kinematics is set up.In the ellipse trace designed for the effector,the simulation results including both velocity and acceleration of end effector's centroid and the velocity varying of cables have showed.The equipment of control system is constructed.The results indicate that the velocity and acceleration of cables are continuous and the method presented is available and universal.国家自然笠学基金资助项目(50475099

System simulation of vertical 3-DOF cord-drawn parallel mechanism

给出所设计的立面一个转动两个平动(1R2T)三自由度绳牵引并联机构的模型.针对此机构模型,建立了运动学逆解模型;接着提出两种计算绳拉力的算法,并具体分析了其中一种算法.以末端执行器实现椭圆型的运动轨迹为目标,进行轨迹规划,研究绳的运动特性.采用Simlink仿真软件对该系统进行了一系列的仿真,包括:绳长变化、绳的速度、加速度变化以及绳的拉力变化.仿真结果表明:在所规划椭圆轨迹下,所有绳速度、加速度的变化是连续的;一些绳拉力的变化比较大,另一些绳拉力的变化比较小.提出的运动轨迹规划方法,具有通用性.A model of the vertical 1R2T 3-DOF cord-drawn parallel mechanism is presented in this study.Afterwards,a reverse kinematical model is established.The cord tension is subsequently obtained via two different calculations,one of which is analyzed in details.Accordingly,a generic track planning is conducted based on the motion tracking of end manipulator.Consequently,the cord motion characteristics,including variations of cord length,velocity,acceleration and tension,are simulated using Simulink TM.It is indicted that the variation of cord velocity and acceleration is consecutive,whereas the variation of cord tension is not tendentious.国家自然科学基金资助项目(50475099

On Wire-driven Parallel Suspension Systems for Static and Dynamic Derivatives of Aircraft in Low-speed Wind Tunnels

为了用同一套绳牵引并联支撑系统来实现低速风洞静导数和动导数实验,采用理论与实验相结合的方法,总结了在WdPSS-8项目中所做的研究工作。结果表明,传统的杆支撑系统存在如支架对空气流场的影响等不可避免的缺陷;张线支撑系统很适合用于飞行器的静导数实验中,但它不能用在飞行器的动导数实验中;绳牵引并联支撑系统WdPSS-8能成功用于静导数实验中,且它在动导数实验中有潜在用途。WdPSS-8项目中的理论问题都得到解决,但实验方面还有不少问题有待解决。In order to use the same wire-driven parallel suspension system to implement static and dynamic derivative experiments in low-speed wind tunnels,a survey of the research work addressing the wire-driven parallel suspension system with eight wires(WDPSS-8) projects is presented in this article.The research methodology combines both theoretical and experimental aspects.The results show that,there are some unavoidable drawbacks,such as the interference of the streamline flow brought by the strut in the traditional suspension system.Moreover,cable-mounted systems are suitable for experiments of the static derivatives of the aircraft;however,they cannot be used in the experiments of dynamic derivatives;WDPSS-8 can be successfully used in experiments of static derivatives,and it has the potentiality to be used in experiments of dynamic derivatives.The issues in the theoretical aspect have been addressed.However,much work has to be done in the experimental aspects.国家自然科学基金(50475099);福建省青年科技人才创新基金(2006F3083

Model Aerodynamic Tests with a Wire-driven Parallel Suspension System in Low-speed Wind Tunnel

根据绳牵引并联机构的优点,建造了一种新型的用于低速风洞试验的飞机模型绳牵引并联支撑系统,研究该系统中模型的空气动力参数的测量与计算方法。文中对机构进行了静力学分析,建立了描述实验模型气动载荷的数学模型,提出了通过测量绳系拉力求得模型空气动力参数的解算方法;设计并构建了绳系拉力测量及数据采集系统;将该系统置于开口式回流低速风洞中进行了吹风试验,采集了模型在不同姿态和不同风速下的各牵引绳的拉力数据,并对数据进行了处理分析,通过解算得到了不同吹风条件下模型的气动载荷参数曲线。研究结果表明,绳牵引并联机构用于低速风洞试验的支撑系统是可行的。Owing to the advantages of wire-driven parallel manipulator, a new wire-driven parallel suspension system for airplane model in low-speed wind tunnel is constructed, and the methods to measure and calculate the aerodynamic parameters of the airplane model are studied.In detail, a static model of the wire-driven parallel suspension is analyzed, a mathematical model for describing the aerodynamic loads exerted on the scale model is constructed and a calculation method for obtaining the aerodynamic parameters of the model by measuring the tension of wires is presented.Moreover, the measurement system for wire tension and its corresponding data acquisition system are designed and built.Thereafter, the wire-driven parallel suspension system is placed in an open return circuit low-speed wind tunnel for wind tunnel tests to acquire data of each wire tension when the airplane model is at different attitudes and different wind speeds.A group of curves about the parameters for aerodynamic load exerted on the airplane model are obtained at different wind speeds after the acquired data are analyzed.The research results validate the feasibility of using a wire-driven parallel manipulator as the suspension system for low-speed wind tunnel tests.NationalNaturalScienceFoundationofChina(50475099

野战方舱医院检伤分类虚拟培训系统的建立及应用

检伤分类是伤员流救治、后送的重要环节,也是影响整体救治效果的瓶颈之一〔1〕。随着计算机共享、远程通讯、影像数字化、射频识别等网络技术的日益发展,现有的伤员流救护模式已不能适应高科技条件下大规模伤亡救治的要求〔2-3〕。笔者所在医院结合未来战争和重大自然灾害条件下南京军区重点课题项目(08Z021); 南京军区“十一五”计划课题项目(06MA99

柠檬酸镍(Ⅱ)配合物的合成、光谱和晶体结构

在弱酸性介质中，氯化镍和柠檬酸铵反应可得到镍水合离子与二聚柠檬酸镍配离子的加合配合物（ＮＨ４）［Ｎｉ（Ｈ２Ｏ）６］［Ｎｉ（Ｈｃｉｔ）（Ｈ２Ｏ）２］４·１０Ｈ２Ｏ１。该配合物的晶体属三斜晶系，空间群为Ｐ１，晶胞参数：ａ＝９．７２７３（９），ｂ＝１２．０３４（２），ｃ＝１３．３４８（２），α＝６３．５４（２），β＝８８．４５（１），γ＝８６．２８（１）°，Ｖ＝１３９５．９（３）３，Ｚ＝１，配合物的阳离子为两个铵离子和一个六水合镍离子，阴离子由两个二聚柠檬酸镍［Ｎｉ（Ｈｃｉｔ）（Ｈ２Ｏ）２］２－２组成。在不对称的配阴离子中，两个柠檬酸分别以羟基、α－羧基和一个β－羧基同第一个镍配位，剩下的β－羧基作为桥基同另一个镍配位形成二聚体

集成磁共振成像技术评估COVID-19康复患者神经损伤

目的应用集成磁共振成像技术（SyMRI）评估COVID-19康复患者脑灰质微结构的改变。方法29例COVID-19康复患者分为重症患者组（SG=11例）和普通患者组（OG=18例），选取年龄、性别、体质指数（BMI）和教育年限相匹配的健康志愿者作为健康对照组（HC=23例）。所有受试者均行SyMRI扫描，生成T1、T2定量图谱，利用自动解剖标记（AAL）模板将T1和T2图谱分割成90个感兴趣区（ROIs）。通过对ROI内的所有体素进行平均得到每个ROI的T1、T2弛豫值。分析比较三组间90个脑区的T1、T2值。结果HC相比，SG在双侧眶内额上回、双侧海马旁回、双侧豆状壳核、双侧颞中回、双侧颞下回、左侧眶部额上回、左侧眶部额下回、左侧直回、左侧前扣带与旁扣带脑回、右侧内侧和旁扣带脑回、左侧后扣带回、左侧缘上回的T2值显著升高（P < 0.05）；与OG相比，SG在左侧直回、左侧海马旁回、双侧颞中回、双侧颞下回的T2值显著升高（P < 0.05）。与HC相比SG在双侧眶内额上回、左侧直回、左侧前扣带和旁扣带脑回、右侧后扣带回、左侧海马旁回、左侧舌回、左侧豆状壳核、左侧丘脑的T1值显著升高（P < 0.05）；与OG相比，SG在右侧后扣带回、右侧距状裂周围皮层、左侧豆状壳核的T1值显著升高（P < 0.05）。结论COVID-19患者即使在康复后脑灰质微结构仍可能存在持续性或迟发性损伤，且损伤程度与病情严重程度相关；SyMRI可作为一项敏感的工具评估中枢神经系统（CNS）微结构损伤情况，有助于早期临床诊断