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Fuzzy recognition of missile borne multi-line array infrared detection based on size calculating

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Defence Technology（防务技术） 2021年第4期17卷 1135-1142页

作者： bing-shan Lei Jing Li Wei-na Hao Ke-ding Yan School of Mechanical and Electrical Engineering Xi’an Technological UniversityXi’an710021China School of Electronic and Information Engineering Xi’an Technological UniversityXi’an710021China Key Laboratory of Education Ministry for Modern Design&Rotor-Bearing System Xi’an Jiaotong UniversityXi’an710049China

In order to improve the infrared detection and discrimination ability of the smart munition to the dynamic armor target under the complex background,the multi-line array infrared detection system is established based on the combination of the single unit infrared *** surface dimension features of ground armored targets are identified by size calculating solution *** signal response value and the value of size calculating are identified by the method of fuzzy recognition to make the fuzzy classification judgment for armored *** to the characteristics of the target signal,a custom threshold de-noising function is proposed to solve the problem of signal *** multi-line array infrared detection can complete the scanning detection in a large area in a short time with the characteristics of smart munition in the steady-state scanning *** method solves the disadvantages of wide scanning interval and low detection probability of single unit infrared *** reducing the scanning interval,the number of random rendezvous in the infrared feature area of the upper surface is increased,the accuracy of the size calculating is *** experiments results show that in the fuzzy recognition method,the size calculating is introduced as the feature operator,which can improve the recognition ability of the ground armor target with different shape size.

关键词： Multi-line array infrared detection Size calculating Custom threshold de-noising Fuzzy comprehensive discrimination algorithm

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

Design and Analysis of a Novel 2T2R Parallel Mechanism with the Closed-loop Limbs

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International Journal of Automation and computing 2021年第4期18卷 654-666页

作者： Hai-Rong Fang Peng-Fei Liu Hui Yang bing-shan Jiang School of Mechanical Electronic and Control EngineeringBeijing Jiaotong UniversityBeijing 100044China

This paper presents a novel four degrees of freedom(DOF) parallel mechanism with the closed-loop limbs, which includes two translational(2 T) DOF and two rotational(2 R) DOF. By connecting the proposed parallel mechanism with the guide rail in series,the 5-DOF hybrid robot system is obtained, which can be applied for the composite material tape laying in aerospace industry. The analysis in this paper mainly focuses on the parallel module of the hybrid robot system. First, the freedom of the proposed parallel mechanism is calculated based on the screw theory. Then, according to the closed-loop vector equation, the inverse kinematics and Jacobian matrix of the parallel mechanism are carried out. Next, the workspace stiffness and dexterity analysis of the parallel mechanism are investigated based on the constraint equations, static stiffness matrix and Jacobian condition number. Finally, the correctness of the inverse kinematics and the high stiffness of the parallel mechanism are verified by the kinematics and stiffness simulation analysis, which lays a foundation for the automatic composite material tape laying.

关键词： 2T2R parallel mechanism close loop structure high stiffness kinematics analysis workspace

Correlation between age of onset and gastrointestinal stenosis in hospitalized patients with Crohn's disease

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World Journal of Clinical Cases 2020年第13期8卷 2769-2777页

作者： shan-bing Yang Shu-Wen Du Ji-Heng Wang Department of Gastroenterology the Seventh Medical CenterChinese People’s Liberation Army General HospitalBeijing 100700China

BACKGROUND Patients affected by Crohn's disease(CD)are more likely to develop gastrointestinal stenosis and often undergo surgery during the duration of *** To identify the risk factors for gastrointestinal stenosis in hospitalized CD patients in *** The clinical data of CD patients hospitalized at the Seventh Medical Center,Chinese People's Liberation Army General Hospital from January 2010 to December 2018 were *** with gastrointestinal stenosis were compared to those without gastrointestinal stenosis for clinical *** risk factors for gastrointestinal stenosis were identified using univariate and multivariable logistic regression *** treatments for patients with gastrointestinal stenosis were analyzed,and the characteristics of different treatment methods were *** The incidence of gastrointestinal stenosis was 59.02%in the 122 hospitalized CD *** of onset of more than 40 years(odds ratio[OR]=3.072,95%confidence interval[CI]:1.298-7.272,P=0.009)and duration of disease of more than 5 years(OR=2.101,95%CI:1.002-4.406,P=0.048)were associated with the occurrence of gastrointestinal ***(20.83%)patients did not undergo surgery and received internal medicine and nutrition *** treatments were performed in 72.22%(52)of *** rate of postoperative complications was 15.38%(8 cases),and during a median follow-up period of 46 mo,11.54%(6 cases)underwent reoperation.A total of 29.17%(21 cases)were treated with endoscopic therapy,and during a median follow-up period of 32 mo,76.19%(16 cases)had no surgical event,23.81%(5 cases)failed to avoid surgical treatments,and no serious postoperative complications occurred after endoscopic *** Age of onset of more than 40 years and duration of disease of more than 5 years may be strongly correlated with a higher risk of gastrointestinal stenosis in hospitalized CD *** therapy for gastrointestinal stenosis

关键词： Crohn's disease Gastrointestinal stenosis Age of onset Duration of disease Endoscopy Surgery

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

Promoting electrochemical reduction of CO_(2) to ethanol by B/N-doped sp^(3)/sp^(2) nanocarbon electrode

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Chinese Chemical Letters 2022年第10期33卷 4691-4694页

作者： Yanming Liu Haolei Yang Xinfei Fan bing shan Thomas J.Meyer Key Laboratory of Industrial Ecology and Environmental Engineering(Ministry of Education) School of Environmental Science and TechnologyDalian University of TechnologyDalian 116024China Department of Chemistry University of North Carolina at Chapel HillChapel HillNorth Carolina 27599United States College of Environmental Science and Engineering Dalian Maritime UniversityDalian 116026China

Electrochemical reduction of CO_(2) to value-added chemicals holds promise for carbon utilization and renewable electricity ***,selective CO_(2) reduction to multi-carbon fuels remains a significant ***,we report that B/N-doped sp^(3)/sp^(2) hybridized nanocarbon(BNHC),consisting of ultra-small nanoparticles with a sp^(3) carbon core covered by a sp^(2) carbon shell,is an efficient electrocatalyst for electrochemical reduction of CO_(2) to ethanol at relatively low ***_(2) reduction occurs with a Faradaic efficiency of 58.8%-69.1% for ethanol and acetate production at -0.5∼-0.6 V(***),among which 51.6%-56.0% is for *** high selectivity for ethanol is due to the integrated effect of sp^(3)/sp^(2) carbon and B/N *** sp^(3) carbon and B/N doping contribute to enhanced ethanol production with sp^(2) carbon reducing the overpotential for CO_(2) reduction to ethanol.

关键词： CO_(2)reduction Ethanol B/N-doped sp^(3)/sp^(2)hybridized nanocarbon Electrocatalysis multi-carbon product

Characteristics of Titanocene Catalyst Supported on Palygorskite for Ethylene Polymerization

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Chinese Chemical Letters 2006年第5期17卷 653-656页

作者： Xiao Wei YAN Jing Dai WANG Yi bing shan Yong Rong YANG Department of Chemical Engineering Zhejiang University Hangzhou 310027

A series of heterogeneous catalysts with Cp2TiCl2 supported on palygorskite were prepared and evaluated by ethylene slurry polymerizations. The so-called direct supported catalyst, for which the pretreatment of palygorskite with MAO or Al（i-Bu）3 was not necessary, gave the highest activity among these supported catalysts and could be more robust than homogeneous Cp2TiCl2. With the direct supported catalyst, no significant activity loss was observed under low Al/Ti molar ratios （Al/Ti=300） and the decay of polymerization rate was slower when compared to the other supported catalysts. It was found that the surface Lewis acidity of palygorskite after thermal treatment played an important role in activation of metallocene compound and resulted in high catalyst activity.

关键词： Playgorskite supported catalyst ethylene polymerization Lewis acidity.