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Type Synthesis and Kinematics Performance Analysis of a Class of 3T2R Parallel Mechanisms with Large Output Rotational Angles

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International Journal of Automation and computing 2019年第6期16卷 775-785页

作者： Bing-Shan Jiang hai-Rong Fang hai-qiang zhang School of Mechanical Electronic and Control Engineering Beijing Jiaotong University

Based on Lie group theory and the integration of configuration, a class of 3T2 R(T denotes translation and R denotes rotation) parallel mechanisms with large output rotational angles is synthesized through a five degree of freedom single limb evolving into two five degree of freedom limbs and constraint coupling of each kinematics chain. A kind of 3T2 R parallel mechanisms with large rotational angles was selected from type synthesis of 3T2 R parallel mechanisms, inverse kinematics and velocity Jacobian matrix of the parallel mechanism are established. The performance indices including workspace, rotational capacity, singularity and dexterity of the parallel mechanism are analyzed. The results show that the parallel mechanism has not only large output rotational angles but also better dexterity.

关键词： Type synthesis Lie group theory configuration evolution kinematics performance evaluation

Motion-force Transmissibility Characteristic Analysis of a Redundantly Actuated and Overconstrained Parallel Machine

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International Journal of Automation and computing 2019年第2期16卷 150-162页

作者： hai-qiang zhang hai-Rong Fang Bing-Shan Jiang School of Mechanical Electronic and Control EngineeringBeijing Jiaotong University

This paper presents a novel 1T2R three degrees of freedom redundantly actuated and overconstrained ■parallel machining head(■denotes the active prismatic joint), which can construct 5-axis hybrid machine to complete high speed freedom surface milling for large complex structural components in aerospace. Firstly, based on the screw theory, the mobility of the proposed parallel manipulator is briefly analysed. Secondly, the kinematic inverse position and the parasitic motion of the parallel manipulator are explicitly expressed. Furthermore, motion-force transmission performance evaluation indices are derived in detail via an alternative approach based on the screw theory. More importantly, a simple method for quickly solving the maximum virtual power coefficient is proposed, and the motion-force transmission performance evaluation index is greatly improved. To evaluate the kinematic performance, its workspace is calculated. With numerical examples, performance distribution atlases of the manipulator are depicted visually. The corresponding results illustrate that the proposed parallel manipulator has better orientation workspace and superior motion-force transmission performance than the 2 PRU-PRS parallel manipulator, which proves the validity and applicability of applying this manipulator as a machining head.

关键词： Redundantly actuated overconstrained parallel manipulator motion-force transmission performance workspace

Dynamic Performance Evaluation of a Redundantly Actuated and Over-constrained Parallel Manipulator

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International Journal of Automation and computing 2019年第3期16卷 274-285页

作者： hai-qiang zhang hai-Rong Fang Bing-Shan Jiang Shuai-Guo Wang School of Mechanical.Electronic and Control Engineering Beijing Jiaotong UniversityBeijing 100044China MH Robot&Automation Limited Company Wei fang 262200China

This paper presents a redundantly actuated and over-constrained 2 RPU-2 SPR parallel manipulator with two rotational and one translational coupling degrees of *** kinematics analysis is firstly carried out and the mapping relationship of the velocity,acceleration and the independent parameters between the actuator joint and the moving platform are deduced by using the vector dot product and cross product *** employing d′Alembert′s principle and the principle of virtual work,the dynamics equilibrium equation is derived,and the simplified dynamics mathematical model of the parallel manipulator is further ***,the generalized inertia matrix which can characterize the acceleration performance between joint space and operation space is further separated,and the performance indices including the dynamics dexterity,inertia coupling characteristics,energy transmission efficiency and driving force/torque balance are *** analysis results show that the proposed redundantly actuated and over-constrained 2 RPU-2 SPR parallel manipulator in comparison with the existing non-redundant one has better dynamic comprehensive performance,which can be demonstrated practically by the successful application of the parallel kinematic machine head module of the hybrid machine tool.

关键词： Redundantly actuated over-constrained parallel manipulator dynamics performance index

Design and Analysis of a Novel Hybrid Processing Robot Mechanism

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International Journal of Automation and computing 2020年第3期17卷 403-416页

作者： hai-Rong Fang Tong Zhu hai-qiang zhang Hui Yang Bing-Shan Jiang School of Mechanical Electronic and Control EngineeringBeijing Jiaotong UniversityBeijing 100044China

In order to satisfy the requirements of large workspace and high dexterity for processing equipment of oversized cylindrical boxes′spherical crown surfaces in the aerospace industry,a novel serial-parallel hybrid processing robot mechanism is *** degrees of freedom of the 5PUS-(2UR)PU parallel mechanism are obtained by using the screw *** inverse kinematics of the hybrid mechanism are analyzed and the velocity Jacobian matrix is ***,the constraints of the main factors influencing workspace of the mechanism are given,and the position and posture workspace are ***,the dexterity and stiffness performance of the mechanism is analyzed based on the Jacobian *** virtual prototype is established,and the theoretical calculation and simulation analysis of the hybrid mechanism with arc curve as the processing trajectory are carried out by using Matlab and Adams *** research results show that the mechanism can satisfy the requirements of large workspace and high dexterity of oversized cylindrical boxes′spherical crown surface processing,and has feasibility and practical application value.

关键词： Hybrid mechanism kinematic analysis large workspace dexterity kinematic simulation

Bcklund Transformation and Conservation Laws for the Variable-coefficient N-Coupled Nonlinear Schrdinger Equations with Symbolic Computation

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Acta Mathematica Sinica,English Series 2012年第5期28卷 969-974页

作者： Xiang Hua MENG Bo TIAN Tao XU hai qiang zhang School of Science Beijing University of Posts and Telecommunications Department of Mathematics School of Applied ScienceBeijing Information Science and Technology University

Considering the integrable properties for the coupled equations, the variable-coefficient N- coupled nonlinear Schrodinger equations are under investigation analytically in this paper. Based on the Lax pair with the nonisospectral parameter, a Backlund transformation for such a coupled system denoting in the F functions is constructed with the one-solitonic solution given as the application sample. Furthermore, an infinite number of conservation laws are obtained using symbolic computation.

关键词： Variable-coefficient N-coupled nonlinear SchrSdinger equations Backlund transformation conservation laws solitonic solution symbolic computation

A dual measurement method of strain and temperature

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Journal of Marine Science and Application 2007年第1期6卷 63-68页

作者： JIANG hai-li SUN Wei-min zhang Cong LIU Zhi-hai JIANG Fu-qiang zhang Yang College of Science Harbin Engineering University Harbin 150001 China

With the rapid development of China's foreign trade, the coastal and inland waterway transport has been increased rapidly. The potential market for marine engines is more and more obvious. The measurement of the engine temperature and strain becomes very important. The fluorescence fiber sensors are broadly used to measure temperature, concentration, and pH value, etc. The fluorescence sensing systems are based on different principles, namely fluorescence intensity, fluorescence intensity ratio, and fluorescence lifetime. The fluorescence lifetime is an effective parameter for sensing purpose, because it is independent of the intensity of the pumping source and does not need expensive narrow-band filters. An experiment system has been established, in which some samples were produced to measure the fluorescence lifetime and temperature characteristics and the relationship of the strain and temperature versus the fluorescence lifetime was achieved at the same time. The experiment result was fitted and analyzed. The test results show that the fluorescence lifetime decreases with the increasing of temperature. The change of fluorescence lifetime with the strain is inconspicuous comparing to that with the temperature.

关键词： fluorescence lifetime fluorescence fiber simultaneous measurement temperature strain

Therapeutic effects of Clostridium butyricum on experimental colitis induced by oxazolone in rats

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World Journal of Gastroenterology 2009年第15期15卷 1821-1828页

作者： hai-qiang zhang Tomas T Ding Jun-Sheng Zhao Xin Yang hai-Xia zhang Juan-Juan zhang Yun-Long Cui Qingdao Research Center of Microecology-Engineering Technology Jiaonan 266400 Shandong Province China BRITE/Department of Pharmaceutical Sciences North Carolina Central University Durham NC27707 United States Pathology Department of People's Hospital Jiaonan 266400 Shandong Province China Qingdao East Sea Pharmaceutical Co. Ltd Jiaonan 266400 Shandong Province China

AIM： To evaluate the therapeutic effects of a probiotic supplement （Clostridium butyricum, CGMCC0313 ） in a chemically-induced rat model of experimental colitis. METHODS： An experimental ulcerative colitis model was established by rectal injection of oxazolone into the colon of 40 Wistar rats randomly divided into four groups. The positive control group was sacrificed 3 d after colitis onset. The remaining groups were fed daily with either 2 mL of C. butyricum （2.3 × 10^11 CFU/L）, 2 mL of mesalamine （100 g/L）, or 1 mL of sodium butyrate （50 mmol/L） for 21 d. The animals＇ body weight, behavior, and bowel movements were recorded weekly. After sacrifice, visual and microscopic observations of pathological changes of colon tissue were made, body weight and wet colon mass index were measured and recorded, and serum levels of interleukin-23 （IL-23） and TNF-α were measured using ELISA. Expression of calcitonin gene-related peptide in colon tissue was measured by RT-PCR. Finally, changes in rat intestinal microflora status were measured in all *** the serum levels of both IL-23 and tumor necrosis factor-α （TNF-α） with similar or even better efficiency than that of mesalamine or sodium butyrate. The rat intestinal flora appeared to recover more quickly in the group treated with C. butyricum than in the mesalamine and sodium butyrate groups. Finally, we found that the expression level of calcitonin gene related peptide was elevated in colon tissue in the sodium butyrate treated group but not in the C. butyricum or mesalamine treated groups, indicating a sensitization of colon following sodium butyrate treatment. CONCLUSION： In our experimental colitis model, treatment with C. butyricum CGMCC0313, a probiotic supplement, is at least as efficient as treatment with mesalamine.

关键词： Clostridium butyricum Interleukin-23 Tumor necrosis factor-m Calcitonin gene relatedpeptide Colitis

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图的点可区别的分数边染色数

数学的实践与认识 2017年第19期47卷 245-250页

作者：刘海涛张强兰州城市学院数学学院甘肃兰州730070 北京理工大学管理与经济学院北京100081

讨论了图的点可区别的边染色数在分数图论的拓展,采用分数图论中超图的a:b-染色方法,证明了邻点可区别的分数边染色数与分数边染色数的等价性,同时进一步推导出经典图论中几类点可区别的边染色数概念如κ-D(β)-点可区别的边染色数、点... 详细信息

讨论了图的点可区别的边染色数在分数图论的拓展,采用分数图论中超图的a:b-染色方法,证明了邻点可区别的分数边染色数与分数边染色数的等价性,同时进一步推导出经典图论中几类点可区别的边染色数概念如κ-D(β)-点可区别的边染色数、点可区别的边染色数和边染色数也在分数图论的拓展下具有等价性.

关键词：邻点可区别边染色数分数染色等价性超图

The emerging role of nitric oxide in the synaptic dysfunction of vascular dementia

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Neural Regeneration Research 2025年第2期20卷 402-415页

作者： Xiaorong zhang Zhiying Chen Yinyi Xiong Qin Zhou Ling-qiang Zhu Dan Liu Department of Pathology Affiliated Hospital of Jiujiang UniversityJiujiangJiangxi ProvinceChina Jiujiang Clinical Precision Medicine Research Center JiujiangJiangxi ProvinceChina Center for Cognitive Science and Transdisciplinary Studies Jiujiang UniversityJiangxi ProvinceChina Department of Neurology Affiliated Hospital of Jiujiang UniversityJiujiangJiangxi ProvinceChina Department of Rehabilitation Affiliated Hospital of Jiujiang UniversityJiujiangJiangxi ProvinceChina Department of Pathophysiology School of Basic MedicineTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei ProvinceChina

With an increase in global aging,the number of people affected by cerebrovascular diseases is also increasing,and the incidence of vascular dementia-closely related to cerebrovascular risk-is increasing at an epidemic ***,few therapeutic options exist that can markedly improve the cognitive impairment and prognosis of vascular dementia *** in Alzheimer’s disease and other neurological disorders,synaptic dysfunction is recognized as the main reason for cognitive *** oxide is one of the ubiquitous gaseous cellular messengers involved in multiple physiological and pathological processes of the central nervous ***,nitric oxide has been implicated in regulating synaptic plasticity and plays an important role in the pathogenesis of vascular *** review introduces in detail the emerging role of nitric oxide in physiological and pathological states of vascular dementia and summarizes the diverse effects of nitric oxide on different aspects of synaptic dysfunction,neuroinflammation,oxidative stress,and blood-brain barrier dysfunction that underlie the progress of vascular ***,we propose that targeting the nitric oxide-sGC-cGMP pathway using certain specific approaches may provide a novel therapeutic strategy for vascular dementia.

关键词： endoplasmic reticulum stress endothelial nitric oxide synthase gene therapy nitric oxide NO-sGC-cGMP pathway synaptic dysfunction vascular dementia