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李清照词的拟问艺术
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作者 沈荣森 《成都大学学报(社会科学版)》 2003年第2期79-81,共3页
李清照词以婉约著称 ,其疑问句式也体现了李词的艺术风格。李清照词的疑问句 ,清晰可见 ,形式多样 ,作用鲜明 ,表达巧妙。李清照词拟问 ,用于想象、启迪思路、抒发感情。李词疑问句 ,浸透了作者的忧思 ,体现了情感与思维相融合的一种心... 李清照词以婉约著称 ,其疑问句式也体现了李词的艺术风格。李清照词的疑问句 ,清晰可见 ,形式多样 ,作用鲜明 ,表达巧妙。李清照词拟问 ,用于想象、启迪思路、抒发感情。李词疑问句 ,浸透了作者的忧思 ,体现了情感与思维相融合的一种心理活动 ,是词人的理想精神与现实社会相碰撞的结晶 ,浸染着一种悲剧性的美感。因此 ,李清照词的疑问句 ,比陈述句曲婉 ,比感叹句含蓄 ,蕴涵沉郁思想 ,大大加强了李词的婉约风格。 展开更多
关键词 李清照 婉约 李词 艺术风格
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明代职官奏请取问制度
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作者 周囿杉 柏桦 《西南大学学报(社会科学版)》 CSSCI 北大核心 2018年第4期178-185,共8页
明代职官奏请取问制度,是将职官犯罪情况奏报皇帝,由皇帝决定是否问罪。除了《大明律》"职官有犯"与"军官有犯"所规定的奏请取问之外,在各种典章制度中也有相关的规定。皇帝对奏请问罪的职官采取取问、不取问及便... 明代职官奏请取问制度,是将职官犯罪情况奏报皇帝,由皇帝决定是否问罪。除了《大明律》"职官有犯"与"军官有犯"所规定的奏请取问之外,在各种典章制度中也有相关的规定。皇帝对奏请问罪的职官采取取问、不取问及便宜处置,既有制度上的依据,也有人为的因素,更有政治的需要,存在许多变数。职官奏请取问制度的设计与实施,既反映出君主专制中央集权制度之君权至高无上的特点,也反映出官僚政治的特征,其中蕴涵的政治因素是值得关注的。 展开更多
关键词 明代职官 奏请取 劾奏 问拟 《大明律》
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Some studies on finding the nearest volume-preserving matrix
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作者 沐建飞 黄建国 《Journal of Southeast University(English Edition)》 EI CAS 2005年第1期119-122,共4页
Finding the nearest volume-preserving matrix for a given matrix is studied. Amatrix equation is first obtained, which is a necessary condition for the solution to the problem.Then the equation is solved by the singula... Finding the nearest volume-preserving matrix for a given matrix is studied. Amatrix equation is first obtained, which is a necessary condition for the solution to the problem.Then the equation is solved by the singular value decomposition method. Some additional results arealso provided to further characterize the solution. Using these results, a numerical algorithm isintroduced and a numerical test is given to illustrate the effectiveness of the algorithm. 展开更多
关键词 volume-preserving matrix matrix nearness problem singular valuedecomposition
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CONSTRAINT QUALIFICATIONS AND DUAL PROBLEMS FOR QUASI-DIFFERENTIABLE PROGRAMMING
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作者 殷洪友 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2002年第2期199-202,共4页
In classical nonlinear programming, it is a general method of developing optimality conditions that a nonlinear programming problem is linearized as a linear programming problem by using first order approximations of ... In classical nonlinear programming, it is a general method of developing optimality conditions that a nonlinear programming problem is linearized as a linear programming problem by using first order approximations of the functions at a given feasible point. The linearized procedure for differentiable nonlinear programming problems can be naturally generalized to the quasi differential case. As in classical case so called constraint qualifications have to be imposed on the constraint functions to guarantee that for a given local minimizer of the original problem the nullvector is an optimal solution of the corresponding 'quasilinearized' problem. In this paper, constraint qualifications for inequality constrained quasi differentiable programming problems of type min {f(x)|g(x)≤0} are considered, where f and g are qusidifferentiable functions in the sense of Demyanov. Various constraint qualifications for this problem are presented and a new one is proposed. The relations among these conditions are investigated. Moreover, a Wolf dual problem for this problem is introduced, and the corresponding dual theorems are given. 展开更多
关键词 quasi differentiable programming constraint qualification dual problems
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MULTI-MATERIAL NUMERICAL SIMULATION OF MOVING SHOCK INTERACTING WITH CONSECUTIVE BUBBLES
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作者 张军 任登凤 谭俊杰 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2009年第3期199-205,共7页
Numerical simulations are performed on the interface with large deformation induced by the interaction between a moving shock and two consecutive bubbles. The high performance of the level set method for multi-materia... Numerical simulations are performed on the interface with large deformation induced by the interaction between a moving shock and two consecutive bubbles. The high performance of the level set method for multi-material interfaces is demonstrated. Discontinuous Galerkin finite element method is used to solve Euleri- an equations. And the fifth-order weighted essentially non-oscillatory (WENO) scheme is used to solve the level set equation for capturing multi-material interfaces. The ghost fluid method is used to deal with the interfacial boundary condition. Results are obtained for two bubble interacting with a moving shock. The contours of the constant density and the pressure at different time are given. In the computational domain, three different cases are considered, i.e. two helium bubbles, a helium bubble followed by an R22 bubble in the direction of the moving shock, and an R22 bubble followed by a helium bubble. Computational results indicate that multi-mate- rial interfaces can be properly captured by the level set method. Therefore, for problems involving the flow of three different materials with two different interfaces, each interface separating two different materials can be similarly handled. 展开更多
关键词 finite element method shock problems numerical simulation level set method ghost fluid multimaterial
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A FICTITIOUS DOMAIN METHOD FOR DIRICHLET PROBLEM AND ITS APPLICATIONS TO GENER ALIZED STOKES PROBLEM
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作者 周春华 唐海敏 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2001年第1期22-28,共7页
This paper discusses a fictitious domain method for the linear Dirichlet problem and its applications to the generalized Stokes problem. This method treats Dirichlet boundary condit ion via a Lagrange multiplier tec... This paper discusses a fictitious domain method for the linear Dirichlet problem and its applications to the generalized Stokes problem. This method treats Dirichlet boundary condit ion via a Lagrange multiplier technique and is well suited to the no-slip bound ary condition in viscous flow problems. In order to improve the accuracy of solu tions, meshes are refined according to the a posteriori error estimate. The mini -element discretization is applied to solve the generalized Stokes problem. Fin ally, some numerical results to validate this method are presented for partial d ifferential equations with Dirichlet boundary condition. 展开更多
关键词 fictitious domain Diri chlet problem finite element generalized Stokes problem Lagrange multiplier
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Quasilinear singularly perturbed problem with boundary perturbation 被引量:2
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作者 莫嘉琪 《Journal of Zhejiang University Science》 CSCD 2004年第9期1144-1147,共4页
A class of quasilinear singularly perturbed problems with boundary perturbation is considered. Under suitable conditions, using theory of differential inequalities we studied the asymptotic behavior of the solution fo... A class of quasilinear singularly perturbed problems with boundary perturbation is considered. Under suitable conditions, using theory of differential inequalities we studied the asymptotic behavior of the solution for the boundary value problem. 展开更多
关键词 Quasilinear problem Singular perturbation Boundary perturbation
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Kinematic Analysis of Persian Joint Using 3D Rotation Matrix 被引量:1
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作者 Hoang Nguyen Hoang Vi +1 位作者 Vu Thi Lien Tran The Long 《Journal of Environmental Science and Engineering(A)》 2013年第12期770-775,共6页
This paper has been done on study kinematic problem of Persian joint in a general way. In this study, instead of using simulation analysis method as in the previous researches, the 3D rotation matrix method is applied... This paper has been done on study kinematic problem of Persian joint in a general way. In this study, instead of using simulation analysis method as in the previous researches, the 3D rotation matrix method is applied to present the relationship of angular velocities of input shaft and output shaft. The result shows that when the angle between intersecting shafts changes from 0 to 135°, the angular velocity is maintained constant. This new result completely matches with analysis from kinematic simulation of this mechanism. The obtained result is an important base to solve dynamic problem in order to develop the applicability of this joint in reality. 展开更多
关键词 Kinematic analysis Persian joint constant-velocity joint 3D rotation matrix.
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A finite volume algorithm based on overlapping meshes for simulation of hydrodynamic problems
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作者 Roozbeh PANAHI Mehdi SHFIEEFAR 《Journal of Marine Science and Application》 2009年第4期281-290,共10页
A finite volume algorithm was established in order to investigate two-dimensional hydrodynamic problems. These include viscous free surface flow interaction with free rigid bodies in the case of large and/or relative ... A finite volume algorithm was established in order to investigate two-dimensional hydrodynamic problems. These include viscous free surface flow interaction with free rigid bodies in the case of large and/or relative motions. Two-phase flow with complex deformations at the interface was simulated using a fractional step-volume of fluid algorithm. In addition, body motions were captured by an overlapping mesh system. Here, flow variables are transferred using a simple fully implicit non-conservative interpolation scheme which maintains the second-order accuracy of implemented spatial discretisation. Code was developed and an appropriate set of problems investigated. Results show good potential for development of a virtual hydrodynamics laboratory. 展开更多
关键词 interfacial flow fluid-structure interaciion wave tank
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Full waveform inversion based on improved MLQN method
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作者 LU Xiaoman FENG Xuan +4 位作者 LIU Cai ZHOU Chao WANG Baoshi ZHANG Minghe XU Cong 《Global Geology》 2015年第4期238-244,共7页
Full waveform inversion( FWI) is a challenging data-fitting procedure between model wave field value and theoretical wave field value. The essence of FWI is an optimization problem,and therefore,it is important to stu... Full waveform inversion( FWI) is a challenging data-fitting procedure between model wave field value and theoretical wave field value. The essence of FWI is an optimization problem,and therefore,it is important to study optimization method. The study is based on conventional Memoryless quasi-Newton( MLQN)method. Because the Conjugate Gradient method has ultra linear convergence,the authors propose a method by using Fletcher-Reeves( FR) conjugate gradient information to improve the search direction of the conventional MLQN method. The improved MLQN method not only includes the gradient information and model information,but also contains conjugate gradient information. And it does not increase the amount of calculation during every iterative process. Numerical experiment shows that compared with conventional MLQN method,the improved MLQN method can guarantee the computational efficiency and improve the inversion precision. 展开更多
关键词 MLQN method FR conjugate gradient frequency domain full waveform inversion
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Drum instability of thinning spinning ultra thin-walled tubes with large diameter-to-thickness ratio 被引量:2
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作者 罗不凡 李新和 +1 位作者 张旭 骆亚洲 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第7期2456-2462,共7页
In order to explore drum instability problems of thinning spinning ultra thin-walled tubes with large diameter-to-hickness ratio, experiments of thinning spinning ultra thin-walled tubes with different clearances betw... In order to explore drum instability problems of thinning spinning ultra thin-walled tubes with large diameter-to-hickness ratio, experiments of thinning spinning ultra thin-walled tubes with different clearances between the mandrel and the tube were carried out. The phenomena of drum instability were analyzed. Drum instability mechanism was studied. The important influence of the mandrel-locked ring on stable thinning spinning was found. Besides, two important parameters, namely drum ratio and drum stiffness, were proposed to characterize the drum instability of spinning ultra thin-walled tubes with large diameter-to-thickness ratio. What's more, numerical simulations were applied to explore the influences of different clearance ratios and diameter-to-thickness ratios on the drum instability. As a result, it is found that the mandrel-locked ring is the key to the stability and precision of spinning; drum ratio can reflect the degree of the deformation of the tubes; drum stiffness is a comprehensive index to measure the influences of the tube's own parameters on the spinning instability; both the clearance ratio and diameter-thickness ratio have significant influences on the drum ratio and drum stiffness. 展开更多
关键词 drum instability mechanism clearance ratio mandrel-locked ring drum ratio drum stiffness
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SIMULATED ANNEALING BASED POLYNOMIAL TIME QOS ROUTING ALGORITHM FOR MANETS
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作者 Liu Lianggui Feng Guangzeng 《Journal of Electronics(China)》 2006年第5期691-697,共7页
Multi-constrained Quality-of-Service (QoS) routing is a big challenge for Mobile Ad hoc Networks (MANETs) where the topology may change constantly. In this paper a novel QoS Routing Algorithm based on Simulated Anneal... Multi-constrained Quality-of-Service (QoS) routing is a big challenge for Mobile Ad hoc Networks (MANETs) where the topology may change constantly. In this paper a novel QoS Routing Algorithm based on Simulated Annealing (SA_RA) is proposed. This algorithm first uses an energy function to translate multiple QoS weights into a single mixed metric and then seeks to find a feasible path by simulated annealing. The pa- per outlines simulated annealing algorithm and analyzes the problems met when we apply it to Qos Routing (QoSR) in MANETs. Theoretical analysis and experiment results demonstrate that the proposed method is an effective approximation algorithms showing better performance than the other pertinent algorithm in seeking the (approximate) optimal configuration within a period of polynomial time. 展开更多
关键词 Energy function Multi-constrained Quality-of-Service (QoS) routing Nondeterministic polynomial time complete problem Polynomial time algorithm Simulated annealing
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A New Power Allocation Algorithm in Cognitive Radio Networks 被引量:2
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作者 ZHOU Mingyue ZHAO Xiaohui 《China Communications》 SCIE CSCD 2014年第4期64-72,共9页
Most resource allocation algorithms are based on interference power constraint in cognitive radio networks.Instead of using conventional primary user interference constraint,we give a new criterion called allowable si... Most resource allocation algorithms are based on interference power constraint in cognitive radio networks.Instead of using conventional primary user interference constraint,we give a new criterion called allowable signal to interference plus noise ratio(SINR) loss constraint in cognitive transmission to protect primary users.Considering power allocation problem for cognitive users over flat fading channels,in order to maximize throughput of cognitive users subject to the allowable SINR loss constraint and maximum transmit power for each cognitive user,we propose a new power allocation algorithm.The comparison of computer simulation between our proposed algorithm and the algorithm based on interference power constraint is provided to show that it gets more throughput and provides stability to cognitive radio networks. 展开更多
关键词 cognitive radio power allocation spectrum sharing
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An application-layer based centralized information access control for VPN 被引量:2
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作者 欧阳凯 周敬利 +1 位作者 夏涛 余胜生 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第2期240-249,共10页
With the rapid development of Virtual Private Network (VPN), many companies and organizations use VPN to implement their private communication. Traditionally, VPN uses security protocols to protect the confidentiality... With the rapid development of Virtual Private Network (VPN), many companies and organizations use VPN to implement their private communication. Traditionally, VPN uses security protocols to protect the confidentiality of data, the message integrity and the endpoint authentication. One core technique of VPN is tunneling, by which clients can access the in- ternal servers traversing VPN. However, the tunneling technique also introduces a concealed security hole. It is possible that if one vicious user can establish tunneling by the VPN server, he can compromise the internal servers behind the VPN server. So this paper presents a novel Application-layer based Centralized Information Access Control (ACIAC) for VPN to solve this problem. To implement an efficient, flexible and multi-decision access control model, we present two key techniques to ACIAC—the centralized management mechanism and the stream-based access control. Firstly, we implement the information center and the constraints/events center for ACIAC. By the two centers, we can provide an abstract access control mechanism, and the material access control can be decided dynamically by the ACIAC’s constraint/event mechanism. Then we logically classify the VPN communication traffic into the access stream and the data stream so that we can tightly couple the features of VPN communication with the access control model. We also provide the design of our ACIAC prototype in this paper. 展开更多
关键词 Virtual private network Access control TUNNELING Centralized management STREAM
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Numerical Simulation of Two-dimensional Nonlinear Sloshing Problems
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作者 梁志勇 刘东顺 严承华 《Journal of Donghua University(English Edition)》 EI CAS 2005年第4期41-46,共6页
Numerical simulation of a two-dimensional nonlinear sloshing problem is preceded by the finite element method. Two theories are used. One is fully nonlinear theory; the other is time domain second order theory. A liqu... Numerical simulation of a two-dimensional nonlinear sloshing problem is preceded by the finite element method. Two theories are used. One is fully nonlinear theory; the other is time domain second order theory. A liquid sloshing in a rectangular container subjected to a horizontal excitation is simulated using these two theories. Numerical results are obtained and comparisons are made. It is found that a good agreement is obtained for the case of small amplitude oscillation. For the situation of large amplitude excitation, although the differences between using the two theories are obvious the second order solution can still exhibit typical nonlinear features of nonlinear wave. 展开更多
关键词 numerical simulation sloshing problem finite element nonlinear theory time domain second order theory.
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Dynamic determination reserves of the underground gas storage
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作者 谭羽非 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2004年第5期516-518,共3页
One of the key problems in the use of underground gas storage is frequent leakage. It can lead to the actual gas storage amount being less than that accounted for. Combining numerical simulation and parameter auto fit... One of the key problems in the use of underground gas storage is frequent leakage. It can lead to the actual gas storage amount being less than that accounted for. Combining numerical simulation and parameter auto fit, this paper ascertains the dynamic variation of the pressure in the storage reservoir, adjusts the actual injecting and producing gas to fit the accounted pressure with the tested pressure, obtains the gas leakage of the storage, and then determines the difference between accounted amount and leakage amount. The result is the actual reserves of the storage. The simulation result shows that the method presented can provide a theoretic foundation for estimating the leakage amount, thereby ensuring the actual reserves, searching the leakage route, and reducing leakage by adjusting the storage method. 展开更多
关键词 underground gas storage RESERVES fraction step solution numerical simulation parameter auto fit leakage problem
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Interprofessional education in nursing: The impact of collaboration between physical and mental health care professionals
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作者 Cristina Amparo Munoz-Rubilar Carolina Pezoa Carrillos Claudio Barrales Díaz 《International Journal of Nursing Sciences》 CSCD 2020年第3期262-268,共7页
Objectives:lnterprofessional collaboration in the training of nursing and psychology students helps provide students of both disciplines with the ability and competences they need to best attend to their patients.This... Objectives:lnterprofessional collaboration in the training of nursing and psychology students helps provide students of both disciplines with the ability and competences they need to best attend to their patients.This study implemented and analyzed a method for developing the competences of each discipline in a scenario of joint clinical simulation that incorporates mental and physical health simultaneously,and measured the caring ability of the participating students.Methods:Participants took a self-applied survey measuring their own caring ability.After,a clinical simulation was performed where nursing students performed clinical interviews on psychology students,who acted as standardized patients.Caring abilities were measured in the nursing students,and the psychology students implemented an intervention service measuring caring ability and brief-debrief simulation by coaching to nursing students.Results:The results indicated that the self-applied questionnaire of caring ability resulted in scores significantly higher than what was measured by observers.Conclusions:The results contribute to the development of protocols,training and collaborative work practices in interprofessional education,which allow the scaling of these competences. 展开更多
关键词 Caring ability Mental health Nursing education Nursing students Simulation training Surveys and questionnaires
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Cooperative Game Approach for Scheduling in Two-Virtual-Antenna Cellular Networks with Relay Stations Fairness Consideration 被引量:1
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作者 滕颖蕾 黄韬 +2 位作者 刘媛媛 满毅 宋梅 《China Communications》 SCIE CSCD 2013年第2期56-70,共15页
In thsssse cellular network, Relay Stations (RSs) help to improve the system performance; however, little work has been done considering the fairness of RSs. In this paper, we study the cooperative game approaches for... In thsssse cellular network, Relay Stations (RSs) help to improve the system performance; however, little work has been done considering the fairness of RSs. In this paper, we study the cooperative game approaches for scheduling in the wireless relay networks with two-virtual-antenna array mode. After defining the metric of relay channel capacity, we form a cooperative game for scheduling and present the interpretation of three different utilization objectives physically and mathematically. Then, a Nash Bargaining Solution (NBS) is utilized for resource allocation considering the traffic load fairness for relays. After proving the existence and uniqueness of NBS in Cooperative Game (CG-NBS), we are able to resolve the resource allocation problem in the cellular relay network by the relay selection and subcarrier assignment policy and the power allocation algorithm for both RSs and UEs. Simulation results reveal that the proposed CG-NBS scheme achieves better tradeoff between relay fairness and system throughput than the conventional Maximal Rate Optimization and Maximal Minimal Fairness methods. 展开更多
关键词 relay network resource alloca-tion cooperative game theory NBS
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A Simulation Environment for Intrusion Detection System in IEC 61850 Based Substation Automation System
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作者 YooJin Kwon Seongho Ju Yonghun Lim 《Computer Technology and Application》 2013年第7期335-340,共6页
Greater complexity and interconnectivity across systems embracing electrical power technologies has meant that cyber-security issues have attracted significant attention. In this paper a simulation environment for int... Greater complexity and interconnectivity across systems embracing electrical power technologies has meant that cyber-security issues have attracted significant attention. In this paper a simulation environment for intrusion detection system in IEC 61850 standard-based substation automation system is provided to test simulated attacks on IEDs (intelligent electronic devices). Intrusion detection is the process of detecting malicious attacker, so it is an effective and mature security mechanism to protect electrical facility. However, it is not harnessed when securing IEC 61850 automated substation. To prove the detection capability of the system testing environment was developed to analyze and test attacks simulated with different test cases. It shows that the simulation environment works accordingly to various network traffic scenarios and eventually proves the functionality of intrusion detection system to be later deployed in the real IEC 61850 based substation automation system site. 展开更多
关键词 IEC 61850 substation automation system simulation environment.
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Numerical Simulation of Multicomponent Alloy Solidification
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作者 Vladimir Pavlovich Ginkin Svetlana Mikhailovna Ganina Andrey Valentinovich Kartavykh 《Journal of Mechanics Engineering and Automation》 2014年第10期828-837,共10页
A non-equilibrium model of multicomponent melt solidification has been developed in which a Stefan problem with two boundaries is solved numerically, the boundaries being between the solid phase and the two-phase tran... A non-equilibrium model of multicomponent melt solidification has been developed in which a Stefan problem with two boundaries is solved numerically, the boundaries being between the solid phase and the two-phase transition zone and between the two-phase transition zone and the liquid phase. The two-phase zone is represented as a porous medium with variable porosity. The additional force resisting the melt flow due to porosity and introduced by analogy with Darcy's law is taken into account. Computer simulation has been performed of the experiment on Sn-20 wt.%Pb binary alloy solidification by the method of downward-directed crystallization along the gravity vector. The paper shows the results of a quasi two-dimensional benchmark experiment on horizontal (i.e., at the right angle to the gravity vector) directional solidification of a binary Sn-3 wt.%Pb alloy. The calculations were done using two crystallization models: the equilibrium model and the non-equilibrium one. It is shown that the non-equilibrium model gives a better description of the thermal field evolution and solute distribution caused by natural convection. 展开更多
关键词 SOLIDIFICATION binary alloy mushy zone MACROSEGREGATION CONVECTION heat-mass transfer modelling comparison withexperimental results.
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