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Chinese Journal of Chemical Engineering 2024年第1期65卷 276-285页

作者： yin Wu Yan Sun Department of Biochemical Engineering School of Chemical Engineering and Technology and Key Laboratory of Systems Bioengineering and Frontiers Science Center for Synthetic Biology(Ministry of Education)Tianjin UniversityTianjin 300350China

Biocatalysis in organic solvents(OSs)has numerous important applications,but native enzymes in OSs often exhibit limited catalytic ***,we proposed a computation-aided surface charge engineering strategy to improve the catalytic performance of haloalkane dehalogenase DhaA in OSs based on the energetic analysis of substrate binding to the DhaA *** variants with enhanced OS resistance were obtained by replacing negative charged residues on the surface with positive charged residue(Arg).Particularly,a four-substitution variant E16R/E93R/E121R/E257R exhibited the best catalytic performance(five-fold improvement in OS resistance and seven-fold half-life increase in 40%(vol)dimethylsulfoxide).As a result,the overall catalytic performance of the variant could be at least 26 times higher than the wild-type *** spectroscopy and molecular dynamics simulation studies revealed that the residue substitution mainly enhanced OS resistance from four aspects:(a)improved the overall structural stability,(b)increased the hydrophobicity of the local microenvironment around the catalytic triad,(c)enriched the hydrophobic substrate around the enzyme molecule,and(d)lowered the contact frequency between OS molecules and the catalytic *** findings validate that computationaided surface charge engineering is an effective and ingenious rational strategy for tailoring enzyme performance in OSs.

关键词： Surface charge engineering Organic solvent resistance Molecular dynamics simulation Haloalkane dehalogenase

Finite element modeling of thermo-active diaphragm walls

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Frontiers of Structural and Civil Engineering 2020年第3期14卷 646-663页

作者： Yi RUI Mei yin Centre for Smart Infrastructure and Construction Department of EngineeringUniversity of CambridgeCambridgeCB3 OFAUK Civil and Environmental Engineering Department Brunei UnivisityLondon UBS 3PHUK

There are two major challenges faced by modern society:energy security,and lowering carbon dioxide gas ***-active diaphragm walls have a large potential to remedy one of these problems,since they are a renewable energy technology that uses underground infrastructure as a heat exchange ***,extensive research is required to determine the effects of cyclic heating and cooling on their geotechnical and structural *** this paper,a series of detailed finite element analyses are carried out to capture the fully coupled thermo-hydro-mechanical response bf the ground and diaphragm *** is demonstrated that the thermal operation of the diaphragm wall causes changes in soil temperature,thermal expansion/shrinkage of pore water,and total stress applied on the diaphragm ***,in turmn,cause displacements of the diaphragm wall and variations of the bending ***,these effects on the performance of diaphragm wall are not *** thermally induced bending strain is mainly governed by the temperature differential and uneven thermal expansion/shrinkage across the wall.

关键词： thermo-active diaphragm wall finite element analysis thermo-hyro-mechanical coupling ground source heat pump

The hydrodynamic performance of a turbine in shallow free surface flow

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Journal of Hydrodynamics 2021年第4期33卷 804-820页

作者： Zeda yin Mehdi Esmaeilpour Department of Mechanical Engineering College of Engineering and Computer SciencesMarshall UniversityHuntingtonWV25755USA

The performance and flow field of hydropower turbine in shallow water can be affected by the presence of free surface. Therefore, the influence of free surface on the turbine performance was studied through transient computational fluid dynamics (CFD) analysis. The turbine included three blades made of NACA0018 hydrofoil. Submerged depths and different tip speed ratio (TSR) were two main variables in this numerical simulation. A comprehensive simulation of quantities was performed for submerged depths ranging from h / R = 1.2 to 2.0, and tip speed ratio from λ = 1.0 to 30. The results revealed that the presence of the free surface decreased the power coefficient by 19.05% for the closest submerged depth of h / R = 1.2 at optimal tip speed ratio of λ = 2.5. The wave breaking also occurred when the submerged depth was smaller than h / R = 2.0. In the case of variable pitch, the top speeds for free-to-spin cases were investigated by 6DOF method. The top speed had a 4.24% drop by comparing the largest and the smallest submerged depths. Variable pitch also improved the power coefficient by 28.09% when the free surface was far from the hydropower turbine. However, the power coefficient improvement became significantly small when the hydropower turbine was placed close to the free surface.

关键词： Hydropower turbine free surface computational fluid dynamics(CFD) Froude number tip speed ratio(TSR)

VIBRATION ANALYSIS OF MICROSCALE PLATES BASED ON MODIFIED COUPLE STRESS THEORY

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Acta Mechanica Solida Sinica 2010年第5期23卷 386-393页

作者： Li yin Department of Mechanics Huazhong University of Science and Technology Wuhan 430074 China Hubei Key Laboratory for Engineering Structural Analysis and Safety Assessment Wuhan 430074 China

A non-classical Kirchhoff plate model is developed for the dynamic analysis of microscale plates based on the modified couple stress theory in which an internal material length scale parameter is included. Unlike the classical Kirchhoff plate model, the newly developed model can capture the size effect of microscale plates. Two boundary value problems of rectangular micro- plates are solved and the size effect on the lowest two natural frequencies is investigated. It is shown that the natural frequencies of the microscale plates predicted by the current model are size-dependent when the plate thickness is comparable to the material length scale parameter.

关键词： microscale plate vibration natural frequency modified couple stress theory size effect

A generalized presentation of multi-caloric effects based on exterior derivative theory and its applications

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Communications in Theoretical Physics 2024年第8期76卷 156-163页

作者： Jun yin School of Materials Science and Engineering Nankai UniversityTianjin 300350China School of Mechanical Engineering and Automation Fuzhou UniversityFuzhou 350108China

The emerging concept of multi-caloric effects, introduced in 2010, entails the application of multiple interplay fields to a thermodynamic system. While multi-caloric effects are the main focus of experimental endeavors, theoretical considerations fall short of providing a thorough understanding. This paper introduces a comprehensive presentation on multi-caloric effects,employing the method and theory of exterior derivative formations. It addresses every aspect of thermodynamic systems, showcasing its applicability to multi-caloric materials(both singlephase and multi-phase materials), and its adaptability to different scenarios(either in single or multiple force fields). The formulation of Maxwell relationships, characterized by their generality and universality, enables a clear prediction in entropy and temperature, facilitating a distinct identification between independent and interdependent contributions from multi-caloric effects. These insights hold significant importance in designing and developing specialized thermodynamic materials, optimizing functional performances and exploring innovative mechanisms.

关键词： multicaloric effects Maxwell relations isothermal entropy adiabatic temperature

A local limit theorem for the probability of ruin

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Science China Mathematics 2004年第5期47卷 711-721页

作者： yin Chuancun Department of Mathematics Qufu Normal University Qufu 273165 China

In this paper, we give a result on the local asymptotic behaviour of the probability of ruin in a continuous-time risk model in which the inter-claim times have an Erlang distribution and the individual claim sizes have a distribution that belongs to S(v) with v ≥ 0, but where the Lundberg exponent of the underlying risk process does not exist.

关键词： Cramér-Lundberg model, Erlang risk model, probability of ruin, subexponential distribution.

Assembly design system based on engineering connection

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Frontiers of Mechanical Engineering 2016年第4期11卷 423-432页

作者： Wensheng yin School of Mechanical Science and Engineering Huazhong University ofScience and Technology Wuhan 430074 China

An assembly design system is an important part of computer-aided design systems, which are important tools for realizing product concept design. The traditional assembly design system does not record the connection information of production on the engineering layer; consequently, the upstream design idea cannot be fully used in the downstream design. An assembly design model based on the relationship of engineering connection is presented. In this model, all nodes are divided into two categories: The component and the connection. Moreover, the product is constructed on the basis of the connection relationship of the components. The model is an And/Or graph and has the ability to record all assembly schemes. This model records only the connection information that has engineering application value in the product design. In addition, this model can significantly reduce the number of combinations, and is very favorable for the assembly sequence planning in the downstream. The system contains a connection knowledge system that can be mapped to the connection node, and the connection knowledge obtained in practice can be returned to the knowledge system. Finally, VC++6.0 is used to develop a prototype system called Connect-based Assembly Planning (CAP). The relationship between the CAP system and the commercial assembly design system is also established.

关键词： product design assembly design engineering connection assembly sequence planning

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面向工业物联网的策略隐藏属性基加密方案

现代电子技术 2025年第1期48卷 90-96页

作者：尹建标张言史培中古春生江苏理工学院计算机工程学院江苏常州213001

针对工业物联网中的生产和监管数据易泄露与数据获取中断的问题,提出支持策略隐藏的属性基加密方案。将属性信息分为属性名和属性值进行方案构造,属性值在构造过程中并未暴露并且上传到云服务器的访问策略仅由属性名构成,工业物联网设... 详细信息

针对工业物联网中的生产和监管数据易泄露与数据获取中断的问题,提出支持策略隐藏的属性基加密方案。将属性信息分为属性名和属性值进行方案构造,属性值在构造过程中并未暴露并且上传到云服务器的访问策略仅由属性名构成,工业物联网设备在获取生产信息时不会完整的访问策略,防止了不法分子对设备信息盗取进而导致访问策略及生产信息的泄露。同时,授权多个半可信云服务器,当某个半可信云服务器不能正常工作时可快速根据服务器密钥更新用户私钥,使得其他半可信云服务器接替其工作,保证物联网设备读取数据的连续性。此外,引入属性认证,在撤销过程中无需重更新密文,适用于产生大量数据的物联网环境的撤销。经过安全性分析和性能分析,该方案能抵抗选择明文攻击,且系统初始化、用户密钥生成、加密、解密都具有较高的运行效率。

关键词：工业物联网数据安全策略隐藏单点故障属性认证属性撤销

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Bifurcation analysis of dual-sidestay landing gear locking performance considering joint clearance

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Chinese Journal of Aeronautics 2022年第7期35卷 209-226页

作者： Kui XU yin yin Yixin YANG Hong NIE Xiaohui WEI State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and AstronauticsNanjing 210016China Key Laboratory of Fundamental Science for National Defense-Advanced Design Technology of Flight Vehicle Nanjing University of Aeronautics and AstronauticsNanjing 210016China

Sidestay lock mechanism is an important part of landing gear system,and the locking performance can be analyzed based on changes in its ***,during numerical continuation analysis of fully-rigid dual-sidestay landing gear without clearance,it has been found that the appearance of bifurcation points does not necessarily imply that both sidestay links can be locked *** problem reveals the limitations of fully-rigid model with ideally-articulated in solving dual-sidestay mechanisms with extremely high motion ***,this study proposes a bifurcation analysis method for synchronous locking of dual-sidestay landing gears,which takes into consideration the joint *** in-depth analysis of this problem,we initially build kinematic and mechanical models of a landing gear mechanism that consider joint ***,the models are solved based on *** fundamental causes of synchronous locking are discussed in detail,and the number of bifurcation points is found to be closely related to whether the landing gear is completely ***,the effects of structural parameters on the synchronous locking are analyzed,and the feasible region of parameters satisfying synchronous locking condition is given,which agrees well with the test results.

关键词： Bifurcation Clearance Dual-sidestay landing gear Numerical continuation Synchronous locking

On the solution of Dirichlet problem of complex Monge-Ampère equation on Cartan-Hartogs domain of the second type

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Science China Mathematics 2009年第12期52卷 2829-2840页

作者： yin WeiPing yin XiaoLan School of Mathematical Sciences Capital Normal UniversityBeijing 10048China Technology Center of Software Engineering Institute of SoftwareChinese Academy of SciencesBeijing 100080China Graduate University of Chinese Academy of Sciences Beijing 100049China

Complex Monge-Ampère equation is a nonlinear equation with high degree, so its solution is very difficult to get. How to get the plurisubharmonic solution of Dirichlet problem of complex Monge-Ampère equation on the Cartan-Hartogs domain of the second type is discussed by using the analytic method in this paper. Firstly, the complex Monge-Ampère equation is reduced to a nonlinear second-order ordinary differential equation (ODE) by using quite different method. Secondly, the solution of the Dirichlet problem is given in semi-explicit formula, and under a special case the exact solution is obtained. These results may be helpful for the numerical method of Dirichlet problem of complex Monge-Ampère equation on the Cartan-Hartogs domain.

关键词： complex Monge-Ampère equation Dirichlet problem Cartan-Hartogs domain Kaehler-Einstein metric 65E05 32C17 53C55 35G30