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Journal of Materials science & Technology 2022年第6期101卷 28-36页

作者： Y.T.Zhou X.H.shao s.J.zheng X.l.Ma shenyang National laboratory for Materials science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Tianjin Key laboratory of Materials.l.minating Fabrication and Interface Control Technology School of Materials Science and EngineeringHebei University of TechnologyTianjin 300130China

Cold-drawn pearlitic steel wire is irreplaceably used in industry owing to its outstanding mechanical property which is dominated by the cementite/ferrite(Fe_(3)C/Fe) interfaces in the material. However, the fine structures of the Fe3C/Fe interfaces in the deformed wires are less known to date. In this work, transmission electron microscopic investigation was performed on the atomic structures of the interfaces with the Isaichev orientation relationship(OR) in the wires with progressive deformation strains. In addition to the effect of the dislocation/interface interactions, this work revealed that the deformation-induced partial decomposition of cementite plays an important role in the interface reconstruction during deformation. The interfacial carbon vacancies generated by cementite decomposition and particularly, the amorphization of cementite layers in the sample with ε > 1 could effectively annihilated the interfacial dislocations and consequently relaxed the interfacial stress. The correlations between the interface structure changes and the mechanical properties of the wires were discussed.

关键词： Pearlitic steel Cementite decomposition Interface structure Deformation Transmission electron microscopy

Automatic search of Threshold Implementations of 4-Bit s-Boxes Resisting DPA

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Chinese Journal of Electronics 2017年第1期26卷 93-100页

作者： lIU Bozhong GONG zheng QIU Weidong school of Information security Shanghai Jiao Tong University school of Computer science South China Normal University state Key laboratory of Information security Institute of Information Engineering Chinese Academy of Sciences

The threshold implementation method of substitution box(s-box) has been proposed by Nikova et al. for resisting first-order Differential power attacks with glitches. To lower the time complexity for a threshold implementation of a specific non-linear function, one needs to decompose the function first and then search possible share methods for it. However, the time complexity for this search process is still non-trivial. In this paper, an effective method of searching threshold implementations of4-bit s-boxes is proposed. It mainly consists of two *** the decomposing stage, an efficient way of decomposing an s-box is introduced. For the sharing stage, the search complexity is.l.wered by the technique of time memory trade-off. As a res.l., threshold implementations of various.l.ghtweight block ciphers’ s-boxes are given. Moreover, our method is applied to each 4-bit involutive s-box and some candidates of threshold implementations are presented.

关键词： s-box Differential power attacks Threshold implementation Time memory trade-off

Vascular endothelial growth factor:a double-edged sword in the development of white matter lesions

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Neural Regeneration Research 2025年第1期20卷 191-192页

作者： Narek Manukjan Daniel Fulton Zubair Ahmed WMatthijs Blankesteijn sébastien Foulquier Department of Pharmacology and Toxicology Maastricht UniversityMaastrichtThe Netherlands CARIM-school for Cardiovascular Diseases Maastricht UniversityMaastrichtThe Netherlands Neuroscience and Ophthalmology Institute of Inflammation and AgeingUniversity of BirminghamEdgbastonBirminghamUK Centre for Trauma sciences Research University of BirminghamEdgbastonBirminghamUK MHeNs-school for Mental Health and Neuroscience Maastricht UniversityMaastrichtThe Netherlands Department of Neurology Maastricht University Medical CenterMaastrichtThe Netherlands

As the population ages,the burden of age-related diseases becomes ***,over 55 million people suffer from dementia worldwide,with Alzheimer’s disease being the most common ***,it is becoming clearer that underlying vascular pathology such as cerebral small vess.l.disease(csVD)may be a more detrimental cause for dementia(Cuadrado-Godia et al.,2018).It is estimated that 10%-30%of the elderly population and 35%-90%of all dementia patients exhibit signs of *** term csVD refers to pathology affecting the small vess.l. of the brain,which can lead to lacunar cerebral infarcts,enlarged perivascular spaces,and cortical hemorrhages(Cuadrado-Godia et al.,2018).CsVD is often associated with cognitive decline,gait problems,and dementia(Cuadrado-Godia et al.,2018).

关键词： pathology becoming white

leader-follower: Human-centered intention-guided controller for novel superlimb with application to load-carrying scenarios

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science China Technological sciences 2025年第1期 325-338页

作者： Qinghua ZHANG Xianglong lI Hongwei JING Kerui sUN Yuancheng lI sikai ZHAO lele lI Haotian JU Ziqi WANG Rui WU Tianjiao zheng Jie ZHAO Yanhe ZHU The state Key laboratory of Robotics and system Harbin Institute of Technology The learning Algorithms and systems.l.boratory School of Engineeringécole Polytechnique Fédérale de Lausanne

supernumerary robotic arms(superlimb) are a new type of wearable robot that works clos.l. with humans as a third hand to augment human operation capability. Accurate conveyance of wearers' intentions, allocation of roles, and humancentered interaction considerations are the key points in the process of human–superlimb collaboration. This paper proposes a human-centered intention-guided leader–follower controller that relies on the dynamic modeling of superlimb with application to load-carrying scenarios. The proposed leader–follower controller takes the human as the leader and the superlimb as the follower, achieving effective information communication, autonomous coordination, and good force compliance between superlimb, humans, and the environment under human safety assurance. First, the human–superlimb dynamic system is modeled to achieve force interaction with the environment and wearer. second, to achieve the precise intention extraction of humans, pose data from five visual odometry sensors are fused to capture the human state, the generalized position, the velocity of hands, and the surface electromyography signals from two myoelectric bracelets sensors are processed to recognize the natural hand gestures during load-carrying scenarios by a designed swin transformer network. Then, based on the real-time distance detection between human and mechanical limbs, the security assurance and force-compliant interaction of the human–superlimb system are realized. Finally, the human hand mus.l. intention recognition, human–robot safety strategy verification,and comparative load-carrying experiments with and without the proposed method are conducted on the superlimb *** showed that the task parameters are well estimated to produce more reasonable planning trajectories, and superlimb could well understand the wearer's intentions to switch different superlimb actions. The proposed sensor-based human–robot communication framework motivates future studies of o

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structural phase transition, precursory electronic anomaly, and strong-coupling superconductivity in quasi-skutterudite (sr1-xCax)3Ir4sn13 and Ca3Rh4sn13

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Chinese Physics B 2018年第7期27卷 163-170页

作者： Jun luo Jie Yang s Maeda zheng li Guo-Qing zheng Institute of Physics Chinese Academy of Sciences and Beijing National Laboratory for Condensed Matter Physics Beijing 100190 China school of Physical sciences University of Chinese Academy of Sciences Beijing 100049 China Department of Physics Okayama University Okayama 700-8530 Japan

The interplay between superconductivity and structural phase transition has attracted enormous interest in recent years. For example, in Fe-pnictide high temperature superconductors, quantum fluctuations in association with structural phase transition have been proposed to lead to many novel physical properties and even the superconductivity its.l.. Here we report a finding that the quasi-skutterudite superconductors （sr1-xCax）3Ir4sn13 （x = 0, 0.5, 1） and Ca3Rh4s.l. show some unusual properties similar to the Fe-pnictides, through 119sn nuclear magnetic resonance （NMR） measurements. In （sr1-xCax）3Ir4sn13, the NMR linewidth increases below a temperature T＊ that is higher than the structural phase transition temperature Ts. The spin-lattice relaxation rate （1/T1 ） divided by temperature （T）, 1/TI T and the Knight shift K increase with decreasing T down to T＊, but start to decrease below T＊, and followed by more distinct changes at Ts. In contrast, none of the anomalies is observed in Ca3Rh4sn13 that does not undergo a structural phase transition. The precursory phenomenon above the structural phase transition resembles that occurring in Fe-pnictides. In the superconducting state of Ca3Ir4sn13, 1/T1 decays as exp（-△/kBT） with a large gap △ = 2.21kBTc, yet without a Hebel-slichter coherence peak, which indicates strong-coupling superconductivity. Our res.l.s provide new insight into the relationship between superconductivity and the electronic-structure change associated with structural phase transition.

关键词： nuclear magnetic resonance antiferromagnetic fluctuation structural phase transition phase diagram

Reliability-based multidisciplinary design optimization using incremental shifting vector strategy and its application in electronic product design

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Acta Mechanica sinica 2018年第2期34卷 285-302页

作者： Z.l.Huang Y.s.Zhou C.Jiang J.zheng X.Han school of Mechanical and Electrical Engineering Hunan City University state Key laboratory of Advanced Design and Manufacturing for Vehicle Body College of Mechanical and Vehicle Engineering Hunan University

Use of multidisciplinary analysis in reliabilitybased design optimization(RBDO) res.l.s in the emergence of the important method of reliability-based multidisciplinary design optimization(RBMDO). To enhance the efficiency and convergence of the overall s.l.tion process,a decoupling algorithm for RBMDO is proposed ***, to decouple the multidisciplinary analysis using the individual disciplinary feasible(IDF) approach, the RBMDO is converted into a conventional form of RBDO. secondly,the incremental shifting vector(IsV) strategy is adopted to decouple the nested optimization of RBDO into a sequential iteration process composed of design optimization and reliability analysis, thereby improving the efficiency significantly. Finally, the proposed RBMDO method is applied to the design of two actual electronic products: an aerial camera and a car pad. For these two applications, two RBMDO models are created, each containing several finite element models(FEMs) and relatively strong coupling between the involved disciplines. The computational res.l.s demonstrate the effectiveness of the proposed method.

关键词： Reliability-based design optimization(RBDO) Multidisciplinary design optimization(MDO) Incremental shifting vector(IsV) Decoupling algorithm Electronic product

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卵磷脂对甲烷水合物形成的影响

化工学报 2007年第11期58卷 2895-2900页

作者：陈卫东 Patil s.l. Kamath V.A. Chukwu G.A. 中海油田服务股份有限公司 University of Alaska-Fairbanks FairbanksAK 99775USA Oil and Gas Division Reliance Industries LimitedNavi MumbaiIndia

建立了用于测定卵磷脂(lecithin)对钻井液中水合物形成影响的实验装置及方法,以理解化学添加剂卵磷脂对北极Cascade地区钻井过程中水合物层的稳定作用。本研究旨在理解卵磷脂对纯水中甲烷水合物形成热力学和动力学的影响。结果表明,卵... 详细信息

建立了用于测定卵磷脂(lecithin)对钻井液中水合物形成影响的实验装置及方法,以理解化学添加剂卵磷脂对北极Cascade地区钻井过程中水合物层的稳定作用。本研究旨在理解卵磷脂对纯水中甲烷水合物形成热力学和动力学的影响。结果表明,卵磷脂基本上不影响甲烷水合物生成的热力学条件,但当卵磷脂在水中的浓度超过0.003g.g-1时,它会影响甲烷水合物的生成速度和数量,是很好的水合物生成动力学促进剂。

关键词：甲烷水合物热力学动力学卵磷脂纯水促进剂

On s-uniform property of compressing sequences derived from primitive sequences modulo odd prime powers

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science China(Information sciences) 2017年第5期60卷 84-95页

作者： Yupeng JIANG Qun-Xiong zheng Dongdai lIN state Key laboratory of Information security Institute of Information EngineeringChinese Academy of Sciences state Key laboratory of Mathematical Engineering and Advanced Computing Zhengzhou Information Science and Technology Institute

let Z/（p;） be the integer residue ring modulo pewith p an odd prime and e 2. We consider the suniform property of compressing sequences derived from primitive sequences over Z/（p;）. We give necessary and sufficient conditions for two compressing sequences to be s-uniform with α provided that the compressing map is of the form φ(x;, x;,..., x;) = g(x;) + η(x;, x;,..., x;), where g(x;) is a permutation polynomial over Z/（p） and η is an（e-1）-variable polynomial over Z/（p）.

关键词： compressing map linear recurring sequence primitive sequence permutation polynomial s uniform

HOT CORROsION BEHAVIOR OF K38G AllOY AND ITs sPUTTERED NANOCRYsTAllINE COATING BY PRE-DEPOsITED s.l.ATE AT 900℃

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Acta Metallurgica sinica(English letters) 2002年第1期15卷 119-122页

作者： s.J. Geng Fuhui Wang s.l. Zhu W.T. Wu state Key laboratory for Corrosion and Protection Institute of Metal Research The Chinese Academy of Sciences Shenyang 110016 China

The sputtered nanocrystalline coating of K38G alloy was obtained by magnetron sput-tering. The hot corrosion behaviors of cast K38G alloy and its sputtered nanocrys-talline coating by pre-deposited 75wt%Na2sO4+25wt%K2sO4 at 900℃ were studied. The res.l.s indicated the occurrence of internal s.l.idation in the cast K38G alloy with pre-deposited s.l.attes of 0.8 and 3.0mg/cm2. However, the internal s.l.idation was not observed in the coating with pre-deposited 0.8mg/cm2 s.l.ate. The hot corrosion resistance of K38G alloy was clearly enhanced through nanocrystallinzation, although the internal s.l.ides were still formed for the coating with s.l.ate deposit of 3mg/cm2. The relevant hot corrosion mechanism was also discussed.

关键词： K38G sputtered nanocrystalline coating hot corrosion

GREEN’s FUNCTION AND EFFECTIVE ElAsTIC sTIFFNEss TENsOR FOR ARBITRARY AGGREGATEs OF CUBIC CRYsTAls

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Acta Mechanica s.l.da sinica 2004年第4期17卷 337-346页

作者： Huang Mojia zheng Chaomei Institute of Engineering Mechanics Nanchang UniversityNanchang 330029China Computer Center Nanchang UniversityNanchang 330029China

A closed but approximate formula of Green’s function for an arbitrary aggregate of cubic crystallites is given to derive the e?ective elastic sti?ness tensor of the polycrystal. This formula, which includes three elastic constants of single cubic crystal and ?ve texture coe?cients, accounts for the e?ects of the orientation distribution function (ODF) up to terms.l.near in the tex- ture coe?cients. Thus it is expected that our formula would be applicable to arbitrary aggregates with weak texture or to materials such as aluminum whose single crystal has weak anisotropy. Three examples are presented to compare predictions from our formula with those from Nishioka and lothe’s formula and synge’s contour integral through numerical integration. As an applica- tion of Green’s function, we brie?y describe the procedure of deriving the e?ective elastic sti?ness tensor for an orthorhombic aggregate of cubic crystallites. The comparison of the computational res.l.s given by the ?nite element method and our e?ective elastic sti?ness tensor is made by an example.

关键词： Green’s function aggregates of cubic crystallites texture coeffcients, effective elastic stiffness tensor