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A Finite and Instantaneous Screw Based Approach for Topology Design and Kinematic Analysis of 5-Axis Parallel Kinematic Machines

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Chinese Journal of Mechanical Engineering 2018年第2期31卷 66-75页

作者： Tao Sun shuo-fei yang Tian Huang Jian S.Dai Key Laboratory of Mechanism Theory and Equipment Design of Ministry of Education Tianjin University School of Engineering The University of Warwick Centre for Robotics Research School of Natural Sciences and Mathematics King’s College London University of London

Unifying the models for topology design and kinematic analysis has long been a desire for the research of parallel kinematic machines(PKMs). This requires that analytical description, formulation and operation for both finite and instantaneous motions are performed by the same mathematical tool. Based upon finite and instantaneous screw theory, a unified and systematic approach for topology design and kinematic analysis of PKMs is proposed in this paper. Using the derivative mapping between finite and instantaneous screws built in the authors’ previous work, the finite and instantaneous motions of PKMs are analytically described by the simple and non?redundant screws in quasi?vector and vector forms. And topological and parametric models of PKMs are algebraically formulated and related. These related topological and parametric models are ready to do type synthesis and kinematic analysis of PKMs under the unified framework of screw theory. In order to show the validity of the proposed approach, a kind of two?translational and three?rotational(2T3R)5?axis PKMs is taken as example. Numerous new structures of the 2T3R PKMs are synthe?sized as the results of topology design, and their Jacobian matrix is obtained easily for parameter optimization and performance evaluation. Some of the synthesized PKMs have outstanding capabilities in terms of large workspaces and flexible orientations, and have great potential for industrial applications of machining and manufacture. Among them, METROM PKM is a typical example which has attracted a lot of attention from global companies and already been developed as commercial products. The approach is a general and unified approach that can be used in the innovative design of different kinds of PKMs.

关键词： Innovative design Parallel kinematic machines Screw theory Finite screw Instantaneous screw

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Initial transcatheter thrombolysis for acute superior mesenteric venous thrombosis

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World Journal of Gastroenterology 2014年第18期20卷 5483-5492页

作者： shuo-fei yang Bao-Chen Liu Wei-Wei Ding Chang-Sheng He Xing-Jiang Wu Jie-Shou Li Research Institute of General Surgery Jinling HospitalMedical School of Nanjing University

AIM: To determine the optimal initial treatment modality for acute superior mesenteric vein thrombosis (ASMVT) in patients with circumscribed peritonitis.

关键词： Acute superior mesenteric venous thrombosis Transcatheter thrombolysis Initial management Circumscribed peritonitis

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Open surgical treatment for rare epithelioid hemangioendothelioma of the common femoral vein

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Journal of Interventional Medicine 2019年第4期2卷 178-180页

作者： Xiangjiang Guo shuo fei yang Guan hua Xue Jia quan Chen Hao Zhang Lan Zhang Department of Vascular Surgery Renji HospitalSchool of MedicineShanghai Jiaotong UniversityShanghai200127China

Epithelioid hemangioendothelioma is a very rare disease affecting big blood vessels,especially *** have been very few articles describing the *** hereby present the case of a 56-year-old woman presenting with lower limb edema,who was initially being treated for residual thrombus in the common femoral vein but was eventually diagnosed with epithelioid hemangioendothelioma(EHE).The common femoral vein was resected and reconstructed using the external jugular *** additional therapy was *** this article,previous literature about EHE has been reviewed and oncologic principles have been discussed.

关键词： Open surgical treatment rare epithelioid hemangioendothelioma common femoral vein

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肝癌干细胞的研究进展

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世界华人消化杂志 2009年第36期17卷 3704-3710页

作者：宋凯杨硕菲吴俊华江春平南京大学医学院江苏省南京市210046 南京大学肝胆研究所江苏省南京市210008 南京大学医学院附属鼓楼医院肝胆外科江苏省南京市210008

肿瘤干细胞已经被证实存在于一些肿瘤组织中,而肝癌干细胞是否存在仍未得到确切的结果.通过实验,研究人员对于肝癌干细胞的来源提出了两个假说:成熟肝细胞的去分化与肝干细胞的"成熟受阻".目前后者是较为公认的肝癌形成途径.同时,为了... 详细信息

肿瘤干细胞已经被证实存在于一些肿瘤组织中,而肝癌干细胞是否存在仍未得到确切的结果.通过实验,研究人员对于肝癌干细胞的来源提出了两个假说:成熟肝细胞的去分化与肝干细胞的"成熟受阻".目前后者是较为公认的肝癌形成途径.同时,为了得到肝癌干细胞存在的直接证据,研究人员一直致力于其表面标志物的研究,希望通过得到理想的标志物来鉴定分选出肝癌干细胞.SP细胞与肝癌干细胞的研究也是目前研究的热点.因此,肝癌干细胞的研究将会对肝癌的诊断和治疗产生重大的意义.

关键词：肝癌干细胞表面标志物侧群细胞靶向治疗

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硫掺杂氧化钨电催化剂的析氢性能研究

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陕西科技大学学报 2025年第1期43卷 107-114,125页

作者：贾鹏飞杨军李硕郑璐瑶张煜国陕西科技大学材料科学与工程学院陕西西安710021

通过硫掺杂来改善氧化钨(WO_(3))电催化剂活性不足和反应动力学缓慢的问题.采用二次煅烧法成功合成了硫掺杂氧化钨(S-WO_(3))电催化剂,并系统地研究了掺杂浓度对其形貌、结构和电化学性能的影响.结果表明,硫掺入氧化钨后能够在引入氧缺... 详细信息

通过硫掺杂来改善氧化钨(WO_(3))电催化剂活性不足和反应动力学缓慢的问题.采用二次煅烧法成功合成了硫掺杂氧化钨(S-WO_(3))电催化剂,并系统地研究了掺杂浓度对其形貌、结构和电化学性能的影响.结果表明,硫掺入氧化钨后能够在引入氧缺陷的同时调控电子结构,显著提高了氧化钨的电催化活性.使用硫粉量为0.11 g的S-WO_(3)-1催化剂具有最佳的硫掺杂浓度.为了实现10 mA cm^(-2)的电流密度仅仅需要161 mV过电位,并且能够持续长达30000 s的析氢过程,显示出优异的催化活性和循环稳定性.本研究为开发掺杂型高效析氢电催化剂提供了新途径.

关键词：电催化剂析氢反应氧化钨硫掺杂电子结构

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Bioinspired All‑Fibrous Directional Moisture‑Wicking Electronic Skins for Biomechanical Energy Harvesting and All‑Range Health Sensing

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Nano-Micro Letters 2023年第4期15卷 277-293页

作者： Chuanwei Zhi shuo Shi Shuai Zhang Yifan Si Jieqiong yang shuo Meng Bin fei Jinlian Hu Department of Biomedical Engineering City University of Hong KongHong Kong S.A.R 999077China Institute of Textiles and Clothing The Hong Kong Polytechnic UniversityHong Kong S.A.R 999077China City University of Hong Kong Shenzhen Research Institute Shenzhen 518057People’s Republic of China

Electronic skins can monitor minute physiological signal variations in the human skins and represent the body’s state,showing an emerging trend for alternative medical diagnostics and human-machine *** this study,we designed a bioinspired directional moisture-wicking electronic skin(DMWES)based on the construction of heterogeneous fibrous membranes and the conductive MXene/CNTs electrospraying *** moisture transfer was successfully realized by surface energy gradient and push-pull effect via the design of distinct hydrophobic-hydrophilic difference,which can spontaneously absorb sweat from the *** DMWES membrane showed excellent comprehensive pressure sensing performance,high sensitivity(maximum sensitivity of 548.09 kPa^(−1)),wide linear range,rapid response and recovery *** addition,the single-electrode triboelectric nanogenerator based on the DMWES can deliver a high areal power density of 21.6μW m^(−2) and good cycling stability in high pressure energy ***,the superior pressure sensing and triboelectric performance enabled the DMWES for all-range healthcare sensing,including accurate pulse monitoring,voice recognition,and gait *** work will help to boost the development of the next-generation breathable electronic skins in the applications of AI,human-machine interaction,and soft robots.

关键词： Bioinspired Electrospinning Electronic skin Directional moisture wicking MXene

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Enhanced electrochemical oxidation of benzene and toluene in aqueous environments using Sb–SnO2-doped TiO2 nanotubes modified by hydrophobic polytetrafluoroethylene（PTFE）

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Progress in Natural Science:Materials International 2024年第5期34卷 1009-1020页

作者： Yameng Li shuo Zhang Peizhen yang Yilin yang fei Chen Xiang Liu Miao Li School of Environment Tsinghua University Tianjin Key Laboratory of Water Resources and Environment Tianjin Normal University

The presence of benzene and toluene in groundwater poses a serious threat to both aquatic ecosystems and human health. The electrochemical removal of these contaminants is primarily hindered by the low generation yield of reactive oxygen species（ROS）. Herein, polytetrafluoroethylene（PTFE） was electrodeposited onto the surface of Sb–SnO2-doped TiO2nanotubes（TNT/Sb–SnO2/5PTFE-300） to enhance electrochemical activity. The resulting nanoelectrode achieved removal efficiencies of 96.2 % for benzene and 97.6 % for toluene. The minimal variation in the degradation of benzene and toluene following 8 cycles of use verified its stability. Experiments confirmed that ·OH was the primary ROS. Hydrophobic surface of the nanoelectrode promoted the one-electron reaction of H2O oxidation, leading to ·OH concentrations that were 54.0 and 27.5 times higher, respectively, than those produced by Ti/Sb–SnO2, and 4.7 and 2.0 times higher, respectively, than those produced by TNT/Sb–***, intermediate products suggested the ring-opening of benzene and toluene, yielding easily degradable small organic molecules. The electrochemical oxidation（EO） process revealed a competitive relationship between benzene and toluene, with toluene exhibiting stronger competitive effects（kinetic constant was 2.1 times that of benzene）. The efficient nanoelectrode provide a novel approach for the removal of benzene and toluene from aquatic environments through EO.

关键词： Aquatic environment remediation Benzene and toluene removal Competitive oxidation Electrochemical oxidation Hydrophobicity

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OPTIMAL QUADRATIC NITSCHE EXTENDED FINITE ELEMENT METHOD FOR INTERFACE PROBLEM OF DIFFUSION EQUATION

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Journal of Computational Mathematics 2018年第5期36卷 693-717页

作者： fei Wang shuo Zhang School of Mathematics and Statistics Xi'an Jiaotong University Xi'an 710049 China Department of Mathematics Pennsylvania State University University Park PA 16802 USA. LSEC ICMSEC NCMIS Academy of Mathematics and System Sciences Chinese Academy of Sciences Beijing 100190 China.

In this paper, we study Nitsche extended finite element method （XFEM） for the inter- face problem of a two dimensional diffusion equation. Specifically, we study the quadratic XFEM scheme on some shape-regular family of grids and prove the optimal convergence rate of the scheme with respect to the mesh size. Main efforts are devoted onto classifying the cases of intersection between the elements and the interface and prove a weighted trace inequality for the extended finite element functions needed, and the general framework of analysing XFEM c^n be implemented then.

关键词： Interface problems Extended finite element methods Error estimates Nitsche's scheme Quadratic element.

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Aircraft Observation and Simulation of the Supercooled Liquid Water Layer in a Warm Conveyor Belt over North China

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Advances in Atmospheric Sciences 2024年第3期41卷 529-544页

作者： Jiefan yang fei YAN Hengchi LEI shuo JIA Xiaobo DONG Xiangfeng HU Key Laboratory of Cloud Physics and Severe Storms Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Weather modification office of Hebei Province Hebei Meteorology AdministrationShijiazhuang 050000China

This paper studied a snow event over North China on 21 February 2017,using aircraft in-situ data,a Lagrangian analysis tool,and WRF simulations with different microphysical schemes to investigate the supercooled layer of warm conveyor belts(WCBs).Based on the aircraft data,we found a fine vertical structure within clouds in the WCB and highlighted a 1-2 km thin supercooled liquid water layer with a maximum Liquid Water Content(LWC) exceeding0.5 g kg^(-1) during the vertical aircraft *** the main features of thermodynamic profiles were essentially captured by both modeling schemes,the microphysical quantities exhibited large diversity with different microphysics *** conventional Morrison two-moment scheme showed remarkable agreement with in-situ observations,both in terms of the thermodynamic structure and the supercooled liquid water ***,the microphysical structure of the WCB clouds,in terms of LWC and IWC,was not apparent in HUJI fast bin *** reduce such uncertainty,future work may focus on improving the representation of microphysics in bin schemes with in-situ data and using similar assumptions for all schemes to isolate the impact of physics.

关键词： warm conveyor belt Microphysical properties supercooled liquid water microphysics schemes

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Relay selection based on MAP estimation for cooperative communication with outdated channel state information

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Chinese Journal of Aeronautics 2013年第3期26卷 661-667页

作者： Ding Wenrui fei Li Gao Qiang Liu shuo Institute of Unmanned Air Vehicle Beihang University School of Electronic and Information Engineering Beihang University

In this paper, we consider an amplify-and-forward （AF） cooperative communication system when the channel state information （CSI） used in relay selection differs from that during data transmission, i.e., the CSI used in relay selection is outdated. The selected relay may not be actually the best for data transmission and the outage performance of the cooperative system will deteriorate. To improve its performance, we propose a relay selection strategy based on maximum a posteriori （MAP） estimation, where relay is selected based on predicted signal-to-noise ratio （SNR）. To reduce the computation complexity, we approximate the a posteriori probability density of SNR and obtain a closed-form predicted SNR, and a relay selection strategy based on the approximate MAP estimation （RS-AMAP） is proposed. The simulation results show that this approximation leads to trivial performance loss from the perspective of outage probability. Compared with relay selection strategies given in the literature, the outage probability is reduced largely through RS-AMAP for medium-to-large transmitting powers and medium-to-high channel correlation coefficients.

关键词： Cooperative communication MAP estimation Outdated CSI Relay selection Wireless networks

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