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Advances of graphene application in electrode materials for lithium ion batteries

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Science China(Technological Sciences) 2015年第11期58卷 1829-1840页

作者： LU XiaoYu jin XiHai SUN jing State Key Lab of High Performance Ceramics and Superfine Microstructure Shanghai Institute of Ceramics Chinese Academy of Sciences

The demands for better energy storage devices due to fast development of electric vehicles(EVs) have raised increasing attention on lithium ion batteries(LIBs) with high power and energy densities. In this paper, we provide an overview of recent progress in graphene-based electrode materials. Graphene with its great electrical conductivity and mechanical properties have apparently improved the performance of traditional electrode materials. The methods and electrochemical properties of advanced graphene composite as cathode and anode for LIBs are reviewed. Two novel kinds of graphene hybrid materials are specially highlighted: three-dimensional porous and flexible binder-free graphene-based materials. Challenges for LIBs and future research trend in the development of high-performance electrode materials are further discussed.

关键词： lithium ion batteries (LIBs) graphene cyclability rate capability nanomaterials three dimensional structure flexibleand binder-free electrode

Error analysis and a new steering law design for spacecraft control system using SGCMGs

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Acta Mechanica Sinica 2011年第5期27卷 803-808页

作者： jin jin jing-Rui Zhang Zao-Zhen Liu Beijing Institute of Technology School of Aerospace Engineering100081 Beijing China

Based on the singular value decomposition theory,this paper analyzed the mechanism of escaping/avoiding singularity using generalized and weighted singularity-robust steering laws for a spacecraft that uses single gimbal control moment gyros （SGCMGs） as the actuator for the attitude control *** expression of output-torque error is given at the point of singularity,proving the incompatible relationship between the gimbal rate and the output-torque *** method of establishing a balance between the gimbal rate and the output-torque error is discussed,and a new steering law is *** results show that the proposed steering law can effectively drive SGCMGs to escape away from singularities.

关键词： Single gimbal control moment gyros (SGCMGs) Attitude control Singularity analysis Steering law

A New Method for Finding Impossible Differentials of Generalized Feistel Structures

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Chinese Journal of Electronics 2018年第4期27卷 728-733页

作者： CUI Ting jin Chenhui MA jing Information Science and Technology Institute

Impossible differential cryptanalysis is one of the most powerful attacks against modern block *** most cases, the resistance of a block cipher against impossible differential cryptanalysis can be measured by the length of the longest impossible differentials. By taking a closer look into the round function, we present a new method to find longer impossible differentials of wordoriented generalized Feistel structures. We conclude the existence of impossible differentials by the nonzero points of the XOR-ed masked differences in the middle *** method uses differential style and its nonzero point to find the impossible differential, which is much easier than the classical impossible differential searching *** applying our method, we can find several longest impossible differentials of some famous block cipher structures with SP(Substitution-permutation) round *** some extra conditions of the round function are taken into consideration(e.g. the permutation layer is designed as binary matrix or some sparse matrix), longer impossible differentials could be achieved by our method.

关键词： Impossible differential Generalized Feistel structure Differential style Nonzero point method

Priority probability deceleration deadline-aware TCP

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Journal of Systems Engineering and Electronics 2015年第3期26卷 595-602页

作者： jin Ye jing Lin Jiawei Huang School of Computer and Electronic Information Guangxi University Guangxi Experiment Center of Information School of Information and Communication Guilin University of Electronic Technology School of Information Science and Engineering Central South University

In modern data centers, because of the deadline- agnostic congestion control in transmission control protocol （TCP）, many deadline-sensitive flows can not finish before their deadlines. Therefore, providing a higher deadline meeting ratio becomes a critical challenge in the typical online data intensive （OLDI） ap- plications of data center networks （DCNs）. However, a problem named as priority synchronization is found in this paper, which de- creases the deadline meeting ratio badly. To solve this problem, we propose a priority probability deceleration （P2D） deadline-aware TCP. By using the novel probabilistic deceleration, p2D prevents the priority synchronization problem. Simulation results show that P2D increases the deadline meeting ratio by 20% compared with D2TCP.

关键词： data center networks (DCNs) deadline priority synchronization transport control protocol (TCP).

Low-Dimensional SIR Epidemic Models with Demographics on Heterogeneous Networks

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Journal of Systems Science & Complexity 2018年第5期31卷 1103-1127页

作者： jing Wenjun jin Zhen ZHANG Juping Complex Systems Research Center Shanxi University

To investigate the impacts of demographics on the spread of infectious diseases, a susceptib- le-infectious-recovered （SIR） pairwise model on heterogeneous networks is established. This model is reduced by using the probability generating function and moment closure approximations. The basic reproduction number of the low-dimensional model is derived to rely on the recruitment and death rate, the first and second moments of newcomers＇ degree distribution. Sensitivity analysis for the basic reproduction number is performed, which indicates that a larger variance of newcomers＇ degrees can lead to an epidemic outbreak with a smaller transmission rate, and contribute to a slight decrease of the final density of infectious nodes with a larger transmission rate. Besides, stochastic simulations indicate that the low-dimensional model based on the log-normal moment closure assumption can well capture important properties of an epidemic. And the authors discover that a larger recruitment rate can inhibit the spread of disease.

关键词： Complex networks demographic process moment closure approximation probability gen-erating function.

某高校护理专业学生失眠现状及相关因素的研究

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卫生职业教育 2025年第1期43卷 122-125页

作者：金亚萍杜晶宁夏医科大学护理学院宁夏银川750004 宁夏医科大学第二附属医院宁夏银川750004

目的调查医学院校在校护理专业学生失眠现状,进一步探讨学生失眠相关危险因素,为提升学生生活品质提供参考。方法采取整群抽样法选取某医学院校全日制护理专业学生为研究对象,采用一般资料调查表、匹兹堡睡眠质量指数量表分析其失眠现... 详细信息

目的调查医学院校在校护理专业学生失眠现状,进一步探讨学生失眠相关危险因素,为提升学生生活品质提供参考。方法采取整群抽样法选取某医学院校全日制护理专业学生为研究对象,采用一般资料调查表、匹兹堡睡眠质量指数量表分析其失眠现状及其相关因素。结果护理专业学生失眠发生率为28.5%,电子产品使用时间、宿舍环境对睡眠质量的影响较大(P<0.05)。结论护理专业学生失眠发生率较高,应引起重视。为提高学生睡眠质量,使其身心健康发展,应加强睡眠健康教育,改善其睡眠环境,从而使其改变不良的睡眠习惯。

关键词：护理专业在校学生失眠

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Classification of Positive Solutions to a Divergent Equation on the Upper Half Space

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Acta Mathematica Sinica,English Series 2022年第3期38卷 499-509页

作者： jin Ge YAO jing Bo DOU School of Mathematics and Statistics Shaanxi Normal UniversityXi’an710119P.R.China

In this paper we classify the positive solutions of the divergent equation with Neumann boundary on the upper half space{-div(t^(α)∇u)=t^(β)f(u),(y,t)∈R^(n+1)_(+),lim t→0^(+)t^(α)■u/■t=0 by the method of moving spheres and Kelvin transformations,where n≥1,α>0,β>−1,n−1/n+1β≤α<β+2,and f:(0,∞)→(0,∞)is non-negative continuous function satisfying some *** equation arises from a weighed Sobolev inequality involving divergent operator div(t^(α)∇u)on the upper half space.

关键词： Divergent operator Liouville theorem Neumann boundary method of moving spheres Kelvin transformation

Pitting corrosion resistance of a novel duplex alloy steel in alkali-activated slag extract in the presence of chloride ions

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International Journal of Minerals,Metallurgy and Materials 2017年第10期24卷 1134-1144页

作者： jin-jie Shi jing Ming Xin Liu Jiangsu Key Laboratory of Construction Materials School of Materials Science and Engineering Southeast University Nanjing 211189 China

In this study, two types of reinforcing steels(conventional low-carbon steel and a novel duplex alloy steel with Cr and Mo) were exposed to chloride-contaminated extract solutions(ordinary Portland cement(OPC) extract and alkali-activated slag(AAS) extract) to investigate their pitting corrosion resistance. The results confirm that the pitting corrosion resistance of the alloy steel is much higher than that of the low-carbon steel in both extract solutions with various Na Cl concentrations. Moreover, for each type of steel, the AAS extract contributes to a higher pitting corrosion resistance compared with the OPC extract in the presence of chloride ions, likely because of the formation of flocculent precipitates on the steel surface.

关键词： pitting corrosion resistance alloy steel alkali-activated slag chloride ions electrochemical impedance spectroscopy cyclic potentiodynamic polarization

Three-dimensional Numerical Simulation of Viscoelastic Phase Separation under Shear: the Roles of Bulk and Shear Relaxation Moduli

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Chinese Journal of Polymer Science 2015年第11期33卷 1562-1573页

作者： jing-yi Chen Zhong jin 杨科大 School of Materials Science and Engineering Beihang University Supercomputing Center Computer Network Information Center Chinese Academy of Sciences

The morphological, dynamic and rheological characteristics in the viscoelastic phase separation（VPS） of sheared polymer solutions are investigated by three-dimensional（3D） numerical simulations of viscoelastic model. The simulations are accelerated by graphic process unit（GPU） to break through the limitation of computation power. Firstly, the morphological and dynamic characteristics of VPS under shear are presented by comparing with those in classic phase separation（CPS）. The results show that the phase inversion and phase shrink take place in VPS under shear. Then, the roles of bulk and shear relaxation moduli in VPS are investigated in details. The bulk relaxation modulus slows down the phase separation process under shear, but not affects the dynamic path of VPS. The dynamic path can be divided into three stages： freezing stage, growth stage and stable stage. The second overshoot phenomenon in the shear stress is observed, and explained by the breakdown and reform of string structures. The shear modulus affects morphology evolution in the late stage of VPS under shear.

关键词： Viscoelastic model Phase separation Polymer solution Shear