Dexterous workspace optimization of an asymmetric six-degree of freedom Stewart–Gough platform type manipulator

In this paper, an asymmetric Generalized Stewart–Gough Platform (GSP) type parallel manipulator is designed by considering the type synthesis approach. The asymmetric six-Degree Of Freedom (DOF) manipulator optimized in this paper is selected among the GSPs classified under the name of 6D. The dexterous workspace optimization of Asymmetric parallel Manipulator with tEn Different Linear Actuator Lengths (AMEDLAL) subject to kinematics and geometric constraints is performed by using the Particle Swarm Optimization (PSO). The condition number and Minimum Singular Value (MSV) of homogenized Jacobian matrix are employed to obtain the dexterous workspace of AMEDLAL. Finally, the six-DOF AMEDLAL is also compared with the optimized Traditional Stewart–Gough Platform Manipulator (TSPM) considering the volume of the dexterous workspace in order to demonstrate its kinematic performance. Comparisons show that the manipulator proposed in this study illustrates better kinematic performance than TSPM.     

Acid/base and hydrogen bonding effects on the proton-coupled electron transfer of quinones and hydroquinones in acetonitrile: Mechanistic investigation by voltammetry, H NMR and computation

This report seeks to address the role of hydrogen bonding with Brønsted acids and bases in proton-coupled electron transfer (PCET) as it pertains to concerted or stepwise pathways of quinone (Q) and hydroquinone (QH₂) electrochemistry. This study was performed using a series of techniques that included cyclic voltammetry (CV), digital simulations, computational chemistry and ¹H NMR. Hydrogen bonding was inferred by a decrease in diffusion coefficient (D) values measured using a pulsed gradient echo- (PGE-) ¹H NMR technique. Changes of 40.8% and 37.9% in D values were only noted after the addition of two equivalents of acetate to 1,4-hydroquinone (1,4-QH₂) and catechol (1,2-QH₂), respectively. In contrast, the D values for the addition of selected amines (pyridine, N,N-diisopropylethylamine and triethylamine) changed only 3.2% on average. Quantum mechanical calculations were conducted to determine the pK_a of all quinoid species to serve as a starting point for the determination of equilibrium constants in voltammetric simulations. Simulations indicate that 1,4-benzoquinone undergoes stepwise electron-proton transfer upon addition of acetic acid, N-ethyldiisopropylammonium perchlorate and pyridinium nitrate and were simulated without the presence of hydrogen bonds. The QH₂ compounds show stepwise proton-electron transfers after addition of the both the conjugate amines and acetate.     

大学生的10种价值观-相关行为结构的联系紧密度研究

研究探讨大学生的10种价值观与各自相关行为的相关程度及各价值观一行为表现之间的关系。结果发现，价值观与相关行为结构存在程度不同的相关性，除变量类型和测量来源，动机内容成为更重要的划分依据。     

型钢混凝土柱轴压比限值的研究

文章推导出了具有明显物理意义的型钢混凝土柱轴压比限值的计算公式,且其结果与<混凝土结构设计规范>中规定的钢筋混凝土柱的轴压比限值有很好的吻合度.     

薄膜干涉的色度学分析

从色度学的角度,对薄膜干涉光的颜色进行了定量分析。     

一种基于直方图的图像签名方法

提出了一种基于直方图的图像签名方法.该方法首先提取图像的直方图信息,然后用其生成哈希值,并将所生成的哈希值加密,最终得到图像签名.实验结果显示,该方法能够有效地抵抗旋转,缩放等不修改内容的操作,并能够灵敏的检测出恶意攻击.     

高职学生职业价值观的分析与探讨

运用自编的职业价值观调查表,对我院2003级（包括经管专业、计算机专业、通信专业）学生进行测试,以探讨2003级高职学生的职业价值观特点,以及专业和性别对高职学生职业价值观的影响。     

论《谭政报告》与当代革命军人核心价值观

当代革命军人核心价值观是对《谭政报告》主要精神的传承,强调党对军队的绝对领导;强调军队思想政治教育的重要性;强调人民利益高于一切。当代革命军人核心价值观是对《谭政报告》的创新,大力弘扬爱国主义精神,精忠报国;提升履行职责能力,献身使命;培育崇高的精神追求,崇尚荣誉。培育践行当代革命军人核心价值观,就要铸牢听党指挥的强军之魂、紧贴军队使命任务、坚持事实求是。     

含空值关系数据中规范化的研究

在关系数据库中,由于空值的存在而使得传统数据依赖公理系统的存在性受到了严重的挑战,有的公理在非空值环境下存在,但在空值环境都不存在了,分别对含有空值关系数据库中规范化,即（N）1NF,（N）2NF、（N）3NF、（N）4NF、（N）5NF进行了讨论,并且给出了含有空值关系数据库中的各范式的相应定义、定理和有关概念,研究了相关的理论,还设计出了分解为（N）4NF的分解算法。     

论人与自然和谐发展的价值观

人与自然和谐发展的价值观的提出源于对现时代环境危机和传统价值观的反思。本文首先阐述了这一价值观的现实基础,即人与自然本质上的整体性;其次论述了这一价值观的基本观点,即把内在价值的概念由人扩展到各种物种以及整个自然共同体,同时也强调了人类的实践能动作用和道德代理人作用,并由此推出人类对自然不可推卸的责任和义务;最后归纳了这一价值观的基本原则,即整体优化原则、尊重自然原则和责任原则。