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Compliance Modeling and Analysis of a 3-RPS Parallel Kinematic Machine Module

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Chinese Journal of Mechanical Engineering 2014年第4期27卷 703-713页

作者： ZHANG jun ZHAO Yanqin DAI Jiansheng School of Mechanical Engineering Anhui University of Technology Department of Informatics King's College London

The compliance modeling and rigidity performance evaluation for the lower mobility parallel manipulators are still to be remained as two overwhelming challenges in the stage of conceptual design due to their geometric complexities. By using the screw theory, this paper explores the compliance modeling and eigencompliance evaluation of a newly patented 1T2R spindle head whose topological architecture is a 3-RPS parallel mechanism. The kinematic definitions and inverse position analysis are briefly addressed in the first place to provide necessary information for compliance modeling. By considering the 3-RPS parallel kinematic machine（PKM） as a typical compliant parallel device, whose three limb assemblages have bending, extending and torsional deflections, an analytical compliance model for the spindle head is established with screw theory and the analytical stiffness matrix of the platform is formulated. Based on the eigenscrew decomposition, the eigencompliance and corresponding eigenscrews are analyzed and the platform＇s compliance properties are physically interpreted as the suspension of six screw springs. The distributions of stiffness constants of the six screw springs throughout the workspace are predicted in a quick manner with a piece-by-piece calculation algorithm. The numerical simulation reveals a strong dependency of platform＇s compliance on its configuration in that they are axially symmetric due to structural features. At the last stage, the effects of some design variables such as structural, configurational and dimensional parameters on system rigidity characteristics are investigated with the purpose of providing useful information for the structural design and performance improvement of the PKM. Compared with previous efforts in compliance analysis of PKMs, the present methodology is more intuitive and universal thus can be easily applied to evaluate the overall rigidity performance of other PKMs with high efficiency.

关键词： compliance modeling parallel kinematic machine eigencompliance eigenscrew

Evaluation of Remote-I/O Support for a DSM-Based Computation Offloading Scheme

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Journal of Computer Science & Technology 2017年第5期32卷 957-973页

作者： Yuhun jun Jaemin Lee Euiseong Seo College of Software Sungkyunkwan University Suwon 16419 Korea

Computation offloading enables mobile devices to execute rich applications by using the abundant computing resources of powerful server systems. The distributed shared memory based (DSM-based) computation offloading approach is expected to be especially popular in the near future because it can dynamically migrate running threads to computing nodes and does not require any modifications of existing applications to do so. The current DSM-based computation offloading scheme, however, has focused on efficiently offloading computationally intensive applications and has not considered the significant performance degradation caused by processing the I/O requests issued by offloaded threads. Because most mobile applications are interactive and thus yield frequent I/O requests, efficient handling of I/O operations is critically important. In this paper, we quantitatively analyze the performance degradation caused by I/O processing in DSM-based computation offloading schemes using representative commodity applications. To remedy the performance degradation, we apply a remote I/O scheme based on remote device support to computation offloading. The proposed approach improves the execution time by up to 43.6% and saves up to 17.7% of energy consumption in comparison with the existing offloading schemes. Selective compression of the remote I/O scheme reduces the network traffic by up to 53.5%.

关键词： computation offloading mobile-cloud computing distributed shared memory (DSM) mobile computing

Experimental Study of Operation Performance for Hydrocarbon Fuel Pump with Low Specific Speed

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Journal of Thermal Science 2017年第5期26卷 440-447页

作者： WU Xianyu YANG jun JIN Xuan College of Aerospace Science and Engineering National Univ. of Defense Technology ChangSha 410073 China

In this paper, a small flow rate hydrocarbon turbine pump was used to pressurize the fuel supply system of scramjet engine. Some experiments were carried out to investigate the characteristics of turbine pump driven by nitrogen or combustion gas under different operating conditions. A experimental database with regard to the curves of the rotational speed, mass flow rate and net head with regard to centrifugal pump were plotted. These curves were represented as functions of the pressure and temperature at turbine inlet/outlet and the throttle diameter at downstream of centrifugal pump. A sensitivity study has been carried out based on design of experiments. The experimental was employed to analyze net head of centrifugal and throttle characteristics. The research results can accumulate foundations for the close loop control system of turbine pump.

关键词： expansion cycle scram jet hydrocarbon fuel turbo-pump operation performance

Tunable Rashba spin splitting in quantum-spin Hall- insulator AsF bilayers

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Nano Research 2017年第2期10卷 491-502页

作者： jun Zhao Wanlin Guo Jing Ma School of Chemistry and Chemical Engineering Institute of Theoretical and Computational Chemistry Key Laboratory of Mesoscopic Chemistry of MOE Nanjing University Nanjing 210093 China State Key Laboratory of Mechanics and Control of Mechanical Structures Institute of Nano Science Nanjing University of Aeronautics and Astronau tics Nanjing 210016 China School of Physics and Optoelectronic Engineering Yangtze University Jingzhou 434023 China

Rashba spin splitting （RSS） in quantum-spin Hall （QSH） insulators is of special importance for fabricating spintronic devices. By changing the stacking order, a unique bilayered fluorinated arsenene （AsF） system is demonstrated to simultaneously possess RSS and non-trivial topological electronic states. We show by first-principle calculations that tunable RSS can be realized in bilayered AsF. Intrinsic RSS of 25 meV is obtained in the AA-stacked AsF bilayer by considering the spin-orbit coupling effect. The RSS can be tuned in the range of 0 to 50 meV by applying biaxial strains and can be significantly enhanced up to 186 meV in the presence of an external electric field. The AB-stacked AsF bilayer is shown to be a two-dimensional topological insulator with a sizable bulk bandgap of 140 meV （up to 240 meV）, which originates from the spin-orbit coupling within the p~,y-pz band inversion. Surprisingly, RSS up to 295 meV can be induced in the AB-stacked AsF bilayer by applying an external electric field, while the robust topology property without RSS can be retained under the applied strains. The AsF bilayers with tunable RSS and a nontrivial bandgap with AA- and AB-stacking orders can pave the way for designing spin field-effect transistors and new QSH devices.

关键词： Rashba spin splitting topological insulator bilayer AsF tensile strain electric field

混合动力汽车多能源动力总成的智能体控制技术

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上海交通大学学报 2015年第8期49卷 1108-1113,1122页

作者：牛礼民叶李军阮晓东安徽工业大学机械工程学院安徽马鞍山243032

为提高混合动力汽车的智能化控制水平,进一步改善整车燃油经济性和动力性,提出一种多能源动力总成的多智能体协调控制方法.以并联式混合动力汽车为原型,建立动力总成部件子系统智能体模型,构建多智能体系统协调控制框架,根据不同工况模... 详细信息

为提高混合动力汽车的智能化控制水平,进一步改善整车燃油经济性和动力性,提出一种多能源动力总成的多智能体协调控制方法.以并联式混合动力汽车为原型,建立动力总成部件子系统智能体模型,构建多智能体系统协调控制框架,根据不同工况模式对总成动力进行预分配,利用单智能体的智能行为和多智能体的协作能力解决车辆对复杂路况的自适应问题.在Cruise软件环境下对智能体控制系统和协调控制策略进行了仿真验证,结果表明,动力总成的多智能体协调控制策略正确可行,使混合动力汽车能根据不同工况自适应控制模式,进而对动力进行自适应匹配,能够改善整车燃油经济性和动力性.

关键词：智能体动力总成混合动力汽车协调控制

女大学生生理期负性情绪与自控力的关系研究:以情绪调节自我效能感为中介

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综合护理干预促进语前聋患儿人工耳蜗植入术后听觉言语康复的作用评价

心理月刊 2024年第15期 71-74页

作者：王紫微陈军安徽中医药大学人文与国际教育交流学院安徽合肥230012

目的探究女大学生生理期负性情绪、自控力以及情绪调节自我效能感三者的关联,分析情绪调节自我效能感能否于女大学生生理期的负性情绪和自控力之间发挥中介效用,从而为促进女大学生生理期心理健康提供理论支撑。方法本研究于2023年11月... 详细信息

目的探究女大学生生理期负性情绪、自控力以及情绪调节自我效能感三者的关联,分析情绪调节自我效能感能否于女大学生生理期的负性情绪和自控力之间发挥中介效用,从而为促进女大学生生理期心理健康提供理论支撑。方法本研究于2023年11月采用方便抽样的方法,采用抑郁-焦虑-压力量表(DASS)、自控力量表(SCS)和情绪调节自我效能感量表(ERES)对国内大学的460名本科生进行调查。共收回有效问卷445份,对数据进行相关分析以及中介效应检验。结果(1)女大学生在生理期间,其负性情绪体验与自我控制能力之间展现出显著的负向关联性,同时,这种负性情绪还与情绪调节的自我效能感知存在明显的负相关趋势。相反,自我控制能力与情绪调节的自我效能感知之间则显现出强烈的正向关联,即一者提升时另一者亦随之增强;(2)在女大学生生理期内负性情绪与自我控制能力的动态关系中,情绪调节的自我效能感起到了一个关键的中介桥梁作用,它调节并影响着两者之间的相互作用路径。结论女大学生生理期的负性情绪对该时期的自控力具有负向预测功效;情绪自我调节效能感,乃是个体内心深处对于自身能否成功管理并调节个人情绪状态所持有的一种自信水平,其在负性情绪和自控力之间起到了缓冲效用。

关键词：生理期负性情绪自控力情绪调节自我效能感中介作用

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中国医学文摘（耳鼻咽喉科学） 2024年第4期39卷 224-226,217页

作者：陈晶晶赵君聊城市东昌府区妇幼保健院山东聊城252000

目的分析并评价,为促进语前聋患儿人工耳蜗植入术(CochlearImplantation,CI)后听觉、言语的康复效果,实施综合护理干预的积极价值。方法以2020年9月-2023年10月为病例选取时段,将我院50例接受CI的语前聋患儿纳入研究,依据“平衡序贯法... 详细信息

目的分析并评价,为促进语前聋患儿人工耳蜗植入术(CochlearImplantation,CI)后听觉、言语的康复效果,实施综合护理干预的积极价值。方法以2020年9月-2023年10月为病例选取时段,将我院50例接受CI的语前聋患儿纳入研究,依据“平衡序贯法”分组处理。对照组接受常规护理方案,观察组综合护理干预。结果观察组患儿术后听觉、言语康复效果明显(P<0.05)。与对照组相比,观察组患儿生理机能、社会功能、生理职能等生活质量高于对照组(P<0.05)。观察组家长对护理工作(专科干预、服务态度、护理操作、语言沟通)的满意度更高显示(P<0.05)。结论对接受CI的语前聋患儿而言,综合护理干预优势明显,可促进术后听觉、言语的更好康复。

关键词：语前聋人工耳蜗植入术听觉言语康复生活质量满意度

Two-dimensional metal oxide nanosheets for rechargeable batteries

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Journal of Energy Chemistry 2018年第1期27卷 117-127页

作者： jun Mei Ting Liao Ziqi Sun School of Chemistry Physics and Mechanical EngineeringQueensland University of Technology2 George StreetBrisbane.OLD 4000Australia

Two-dimensional（2D） metal oxide nanosheets have attracted much attention as potential electrode materials for rechargeable batteries in recent years. This is primarily due to their natural abundance, environmental compatibility, and low cost as well as good electrochemical properties. Despite the fact that most metal oxides possess low conductivity, the introduction of some conductive heterogeneous components, such as nano-carbon, carbon nanotubes（CNTs）, and graphene, to form metal oxide-based hybrids,can effectively overcome this drawback. In this mini review, we will summarize the recent advances of three typical 2D metal oxide nanomaterials, namely, binary metal oxides, ternary metal oxides, and hybrid metal oxides, which are used for the electrochemical applications of next-generation rechargeable batteries, mainly for lithium-ion batteries（LIBs） and sodium-ion batteries（SIBs）. Hence, this review intends to functionalize as a good reference for the further research on 2D nanomaterials and the further development of energy-storage devices.

关键词： 2D nanomaterials Metal oxide Lithium-ion battery Rechargeable batteries Sodium-ion battery

强分离条件下自相似集的Lipschitz等价

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数学学报（中文版） 2008年第3期51卷 493-500页

作者：奚李峰阮火军浙江万里学院数学研究所宁波315100 浙江大学理学院数学系杭州310027

利用有向图结构刻画了满足强分离条件的自相似集Lipschitz等价的充要条件.

关键词：分形自相似集 Lipschitz等价