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Product Modular Design Incorporating Preventive Maintenance Issues

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Chinese Journal of Mechanical Engineering 2016年第2期29卷 406-420页

作者： GAO yicong FENG Yixiong tan Jianrong State Key Laboratory of Fluid Power Transmission and Control Zhejiang University

Traditional modular design methods lead to product maintenance problems, because the module form of a system is created according to either the function requirements or the manufacturing considerations. For solving these problems, a new modular design method is proposed with the considerations of not only the traditional function related attributes, but also the maintenance related ones. First, modularity parameters and modularity scenarios for product modularity are defined. Then the reliability and economic assessment models of product modularity strategies are formulated with the introduction of the effective working age of modules. A mathematical model used to evaluate the difference among the modules of the product so that the optimal module of the product can be established. After that, a multi-objective optimization problem based on metrics for preventive maintenance interval different degrees and preventive maintenance economics is formulated for modular optimization. Multi-objective GA is utilized to rapidly approximate the Pareto set of optimal modularity strategy trade-offs between preventive maintenance cost and preventive maintenance interval difference degree. Finally, a coordinate CNC boring machine is adopted to depict the process of product modularity. In addition, two factorial design experiments based on the modularity parameters are constructed and analyzed. These experiments investigate the impacts of these parameters on the optimal modularity strategies and the structure of module. The research proposes a new modular design method, which may help to improve the maintainability of product in modular design.

关键词： modular design modularity strategy preventive maintenance optimization design

Layout design and application of 4D-printing bio-inspired structures with programmable actuators

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Bio-Design and Manufacturing 2022年第1期5卷 189-200页

作者： Siyuan Zeng Yixiong Feng yicong Gao Hao Zheng Jianrong tan State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou 310027China Hangzhou Innovation Institute Beihang UniversityHangzhou 310000China

Four-dimensional(4D)printing is an advanced form of three-dimensional(3D)printing with controllable and programmable shape transformation over *** are used as a controlling factor with multi-stage shape recovery,with emerging opportunities to customize the mechanical properties of bio-inspired *** print pattern of shape memory polymer(SMP)fbers strongly afects the achievable resolution,and consequently infuences several other physical and mechanical properties of fabricated ***,the deformations of bio-inspired structures due to actuator layout are more complex because of the presence of the coupling of multi-directional *** this study,the initial structure was designed from closed-shell behavior and divided into a general unit and actuator unit,the latter responsible for driving the *** stress confrontation between the actuator and the general unit was considered in the layout thermodynamic model,in order to eliminate the transformation produced by the uncontrolled shape memory behavior of the general *** critical and efective strategies for the layout design of actuators were proposed and then applied to achieve the desired accurate deformation of 3D-printed bilayer ***,the proposed approach was validated and adopted for fabricating a complex shell-like gripper structure.

关键词： Bio-inspired structure Layout design Programmable actuators Bilayer structure 4D printing

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惠州市不同水域鲫、鲮鱼重金属含量比较分析

惠州学院学报 2018年第3期38卷 29-36页

作者：马细兰谭烨聪林佳泓黄耀源梁浩亮惠州学院生命科学学院惠州516007 惠州市海洋局海洋技术中心惠州516000

水生环境重金属污染日益严重,水产品安全问题倍受关注.本研究以惠州市内主要河流东江以及其一级支流和二级支流中的鲫、鲮鱼为研究对象,比较重金属元素在鱼类肌肉、鳃、肝脏组织间的含量差异,并分析鱼类重金属含量与环境的相关性.结果如... 详细信息

水生环境重金属污染日益严重,水产品安全问题倍受关注.本研究以惠州市内主要河流东江以及其一级支流和二级支流中的鲫、鲮鱼为研究对象,比较重金属元素在鱼类肌肉、鳃、肝脏组织间的含量差异,并分析鱼类重金属含量与环境的相关性.结果如下:(1)Cu、Pb元素主要存在于肝脏,最高达到7.355μg/g、22.386μg/g;Zn元素主要存在于鳃,最高达到28.017μg/g;Cr元素无明显规律.(2)主要食用部位肌肉中的Cu、Cr、Zn含量较低,含量范围分别为0.093~0.752μg/g、0.057~0.488μg/g、7.841~9.271μg/g,均低于我国水产品食用安全的上限标准:50μg/g、2μg/g、40μg/g,但Pb的含量范围为0.689~7.287μg/g,远高于安全食用上限标准0.5μg/g.(3)除鲮鱼鳃的Pb元素外,东江样品与其他采样点样品间同一组织的Cu、Zn、Cr、Pb元素含量均存在显著差异;鲫鱼肌肉中Zn元素,鳃部的Cu、Zn元素,肝脏的Cu、Pb元素与环境水质的重金属含量均存在密切的相关性;鲮鱼肌肉、鳃和肝脏中的Cu、Zn、Pb元素以及肌肉中Cr元素与环境水质的重金属含量密切相关,因此,鱼类组织中重金属的含量可作为该水域重金属污染的参考指标,也可用该水域的重金属污染情况作为鱼类重金属污染的参考指标.

关键词：鲮鱼鲫鱼重金属不同组织环境相关性

Trajectory optimisation in electrical discharge machining of three-dimensional curved and twisted channels

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Chinese Journal of Aeronautics 2022年第4期35卷 473-484页

作者： Jianshe ZHAO yicong QIU Jian YUAN Chao LIU College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China Laboratory of Integrated Electrical Processing Nanjing HANGPU Machinery Technology Company LimitedNanjing 210000China Military Representative Bureau of the Air Force Equipment Department in Shanghai and Military Representative Office in Zhuzhou Region Zhuzhou 412002China AECC South Industry Company Limited Zhuzhou 412002China

Numerical control electrical discharge machining(NC EDM) is one of the most widely used machining technologies for manufacturing a closed blisk flow path, particularly for three-dimensional(3D) curved and twisted flow channels. In this process, tool electrode design and machining trajectory planning are the key factors affecting machining accessibility and efficiency. Herein, to reduce the difficulty in designing the electrode and its motion path in the closed curved and twisted channels, a heuristic search hybrid optimisation strategy based on channel grids is adopted to realise the initial electrode trajectory design search and optimised size reduction. By transferring the trajectory optimisation constraints from the complex free-form surface to numbered grids, the search is found to be more orderly and accurate. The two trajectory indicators, namely argument angle and minimum distance, are analysed separately for the optimised results of the adaptive learning particle swarm optimisation algorithm, demonstrating that they can meet the actual processing *** results of NC EDM indicate that the motion path generated by this design method can meet the machining requirements of 3D curved and twisted flow channels.

关键词： Blisk Electrical discharge machining(EDM) Electrode Objective functions Trajectory generation

Modular chaotification model with FPGA implementation

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Science China(Technological Sciences) 2021年第7期64卷 1472-1484页

作者： HUA Zhong Yun ZHOU BingHang ZHANG YinXing ZHOU yicong School of Computer Science and Technology Harbin Institute of TechnologyShenzhenShenzhen518055China College of Electrical and Information Engineering Hunan UniversityChangsha410082China Department of Computer and Information Science University of MacaoMacao999078China

Chaotic systems are an effective tool for various applications, including information security and internet of things. Many chaotic systems may have the weaknesses of incomplete output distributions, discontinuous chaotic regions, and simple chaotic *** may result in many negative influences in practical applications utilizing chaos. To deal with these issues, this study introduces a modular chaotification model(MCM) to increase the dynamic properties of current one-dimensional(1 D) chaotic maps. To exhibit the effect of the MCM, three 1 D chaotic maps are improved using the MCM as examples. Studies of the resulting properties show the robust and complex dynamics of these improved chaotic maps. Moreover, we implement these improved chaotic maps of MCM in a field-programmable gate array hardware platform and apply them to the application of PRNG. Performance analyses verify that these chaotic maps improved by the MCM have more complicated chaotic behaviors and wider chaotic ranges than the existing and several new chaotic maps.

关键词： nonlinear system chaotic system field-programmable gate array(FPGA) pseudorandom number generator(PRNG) hardware implementation

安氏Ⅱ类错[牙合]畸形佩戴Twin-block矫治器时上颌骨的应力分布

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中国组织工程研究 2025年第5期29卷 881-887页

作者：李帅刘桦商永慧刘义琮赵启航刘文大连医科大学辽宁省大连市116000 康复大学青岛医院/青岛市市立医院口腔医学中心山东省青岛市266000 青岛市崂山区青岛恩典嘉美口腔门诊部山东省青岛市266100

背景:Twin-block矫治器常用于安氏Ⅱ类错[牙合]畸形的矫治,其刺激下颌骨生长的作用机制已得到许多研究证实,但对上颌骨生长的影响尚不清楚。目的:通过有限元法分析安氏Ⅱ类错[牙合]畸形患者佩戴Twin-block矫治器时上颌骨复合体、周围骨... 详细信息

背景:Twin-block矫治器常用于安氏Ⅱ类错[牙合]畸形的矫治,其刺激下颌骨生长的作用机制已得到许多研究证实,但对上颌骨生长的影响尚不清楚。目的:通过有限元法分析安氏Ⅱ类错[牙合]畸形患者佩戴Twin-block矫治器时上颌骨复合体、周围骨缝及上颌牙列的应力分布。方法:选择在山东省康复大学青岛医院/青岛市市立医院口腔正畸科进行正畸治疗的安氏Ⅱ类错[牙合]畸形患者1例,测量患者佩戴Twin-block矫治器时的咬合力数据,采集其锥形束CT数据,建立包含上颌骨复合体、周边各骨缝、Twin-block矫治器及上颌牙列在内的有限元模型,通过ABAQUS软件模拟患者戴入Twin-block时上颌骨、骨缝及上颌牙列的应力分布与位移。结果与结论:①上颌前牙受到的等效应力明显小于后牙,两侧牙齿的最大等效应力分别为4.7975 MPa和8.7161 MPa,均位于第一前磨牙处;最大位移呈现在两侧上颌切牙处,分别为0.0805 mm和0.0810 mm;②骨缝的最大等效应力为1.284 MPa,主要集中在两侧翼腭缝及额颌缝,其余骨缝受力情况几乎无差异;骨缝的最大位移为0.07 mm,其中翼腭缝的位移量最大,其次是额颌缝;③上颌骨复合体受到的最大等效应力为27.18 MPa,主要集中在上颌骨前面梨状孔两侧、鼻额缝周边及颚骨后部翼腭缝附近;上颌骨的最大位移值为0.07 mm,主要集中于上颌牙槽骨;④结果显示,咬合力通过Twin-block矫治器作用于上颌骨复合体,导致上颌骨顺时针旋转、牙合平面变陡,应采取相应措施补偿这种趋势,例如建牙合过程中考虑上颌磨牙伸长、下颌磨牙压低,不仅能够将牙合平面整平,同时有利于下颌前伸,这将进一步提高Ⅱ类错[牙合]正畸治疗效果。

关键词：错牙合畸形组织构建骨组织工程 Twin-block矫治器功能矫治有限元分析

Recovery of natural active molecules using aqueous two-phase systems comprising of ionic liquids/deep eutectic solvents

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Green Chemical Engineering 2022年第1期3卷 5-14页

作者： yicong Wang Shanshan Wang Leilei Liu Key Laboratory of Hunan Forest Products and Chemical Industry Engineering Jishou UniversityZhangjiajie427000China

Due to environmental protection requirements,extraction of bioactive compounds from plant materials using environment-friendly green solvents has always been a research *** great efforts of scholars have been made in this direction,as well as environment-friendly solvents have been used to develop many innovative extraction *** liquids(ILs)and deep eutectic solvents(DESs)are two kinds of typical designable green solvents,which are potential replacements for traditional volatile organic solvents used for *** the substances action of inorganic salts or polymers,ILs/DESs can form an aqueous two-phase system(ATPS),which has obvious advantages for separating natural *** paper discussed the phase separation principle of ILs/DESs-based ATPSs and reviewed the applications in the extraction of natural active molecules in recent years,as well as to promote the development of separation of the active constituents in Chinese materia medica.

关键词： Ionic liquids Deep eutectic solvents Aqueous two-phase system Natural active molecules Extraction and separation

Viromes in marine ecosystems reveal remarkable invertebrate RNA virus diversity

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Science China(Life Sciences) 2022年第2期65卷 426-437页

作者： Yu-Yi Zhang yicong Chen Xiaoman Wei Jie Cui CAS Key Laboratory of Molecular Virology&Immunology Institut Pasteur of ShanghaiCenter for Biosafety Mega-ScienceChinese Academy of SciencesShanghai 200031China University of Chinese Academy of Sciences Beijing 100049China Laboatory for Marine Biology and Biotechnology Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China

Little is known about ocean viromes and the ecological drivers of the evolution of aquatic RNA *** study employed a meta-transcriptomic approach to characterize the viromes of 58 marine invertebrate species across three *** revealed the presence of 315 newly identified RNA viruses in nine viral families or orders(Durnavirales,Totiviridae,Bunyavirales,Han-taviridae,Picornavirales,Flaviviridae,Hepelivirales,Solemoviridae,and Tombusviridae),with most of them being sufficiently divergent to the already documented ***,this study revealed three marine invertebrate hantaviruses that are rooted to vertebrate hantaviruses,further supporting that hantaviruses may have a marine *** have also found evidence for possible host sharing and switch events during virus ***,we have revealed the hidden diversity of marine invertebrate RNA viruses.

关键词： ocean aquatic invertebrate RNA virome evolution host sharing

Valence electron structure analysis of refining mechanism of Sc and Ti additions on aluminum

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Chinese Science Bulletin 2009年第5期54卷 836-841页

作者： LI PieJie YE yicong HE LiangJu Sino-Russia Light Metals International Cooperate R&D Center Department of Mechanical Engineering Tsinghua University Beijing 100084 China School of Aerospace Tsinghua University Beijing 100084 China

The mechanism of the difference of refining effect between Sc and Ti adding to aluminum can not be explained substantially with traditional theory. Valence electron structures of Al-Ti and Al-Sc alloys have been studied by using the empirical electron theory of solids and molecules (EET). The covalent bond electron numbers and interfacial electron density differences are calculated. The conclusion is that, in the two alloys, different covalent bond electron numbers of nucleation particles, and different electron densities on the interface between the second phase particles and the matrix, fundamentally lead to the difference of refining effect between Sc and Ti adding to aluminum.

关键词：价电子结构经验电子理论细化机制钪钛 Al3Sc Al3Ti