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Comprehensive security risk factor identification for small reservoirs with heterogeneous data based on grey relational analysis model 被引量:6
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作者 Jing-chun Feng Hua-ai Huang +1 位作者 Yao Yin Ke Zhang 《Water Science and Engineering》 EI CAS CSCD 2019年第4期330-338,共9页
Identification of security risk factors for small reservoirs is the basis for implementation of early warning systems.The manner of identification of the factors for small reservoirs is of practical significance when ... Identification of security risk factors for small reservoirs is the basis for implementation of early warning systems.The manner of identification of the factors for small reservoirs is of practical significance when data are incomplete.The existing grey relational models have some disadvantages in measuring the correlation between categorical data sequences.To this end,this paper introduces a new grey relational model to analyze heterogeneous data.In this study,a set of security risk factors for small reservoirs was first constructed based on theoretical analysis,and heterogeneous data of these factors were recorded as sequences.The sequences were regarded as random variables,and the information entropy and conditional entropy between sequences were measured to analyze the relational degree between risk factors.Then,a new grey relational analysis model for heterogeneous data was constructed,and a comprehensive security risk factor identification method was developed.A case study of small reservoirs in Guangxi Zhuang Autonomous Region in China shows that the model constructed in this study is applicable to security risk factor identification for small reservoirs with heterogeneous and sparse data. 展开更多
关键词 Security risk factor identification Heterogeneous data Grey relational analysis model relational degree Information entropy Conditional entropy Small reservoir GUANGXI
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Two Classes of Models of Granular Computing 被引量:1
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作者 Daowu Pei 《南昌工程学院学报》 CAS 2006年第2期52-55,共4页
This paper reviews a class of important models of granular computing which are induced by equivalence relations,or by general binary relations,or by neighborhood systems,and propose a class of models of granular compu... This paper reviews a class of important models of granular computing which are induced by equivalence relations,or by general binary relations,or by neighborhood systems,and propose a class of models of granular computing which are induced by coverings of the given universe. 展开更多
关键词 granular computing GRANULE rough set theory relation based model covering based model
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Developing a Data Modelling Tool to Visualize the Transformation of an ER Diagram into a Relational Schema
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作者 Elitsa Silyanova Arsova Silyan Sibinov Arsov 《Computer Technology and Application》 2012年第3期201-205,共5页
In this paper, the authors present the development of a data modelling tool that visualizes the transformation process of an "Entity-Relationship" Diagram (ERD) into a relational database schema. The authors' foc... In this paper, the authors present the development of a data modelling tool that visualizes the transformation process of an "Entity-Relationship" Diagram (ERD) into a relational database schema. The authors' focus is the design of a tool for educational purposes and its implementation on e-learning database course. The tool presents two stages of database design. The first stage is to draw ERD graphically and validate it. The drawing is done by a learner. Then at second stage, the system enables automatically transformation of ERD to relational database schema by using common rules. Thus, the learner could understand more easily how to apply the theoretical material. A detailed description of system functionalities and algorithm for the conversion are proposed. Finally, a user interface and usage aspects are exposed. 展开更多
关键词 E-learning course data modelling tool entity-relationship model relational model.
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Interpersonal Perception in Virtual Groups: Examining Homophily, Identification and Individual Attraction Using Social Relations Model in Network
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作者 Zuoming Wang 《Social Networking》 2023年第2期45-56,共12页
With the penetration of the Internet, virtual groups have become more and more popular. The reliability and accuracy of interpersonal perception in the virtual environment is an intriguing issue. Using the Social rela... With the penetration of the Internet, virtual groups have become more and more popular. The reliability and accuracy of interpersonal perception in the virtual environment is an intriguing issue. Using the Social relations model (SRM) [1], this paper investigates interpersonal perception in virtual groups from a multilevel perspective. In particular, it examines the following three areas: homophily, identification, and individual attraction, and explores how much of these directional and dyadic relational evaluations can be attributed to the effect of the actor, the partner, and the relationship. 展开更多
关键词 Virtual Groups Interpersonal Perception Social Relations Model HOMOPHILY IDENTIFICATION Individual Attraction
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Business domain oriented AI planning for web service composition
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作者 代钰 杨雷 张斌 《Journal of Southeast University(English Edition)》 EI CAS 2007年第3期421-424,共4页
In order to improve the effectiveness of the artificial intelligence (AI) planning based web service composition problem, a business domain oriented AI planning algorithm for web service composition is introduced. T... In order to improve the effectiveness of the artificial intelligence (AI) planning based web service composition problem, a business domain oriented AI planning algorithm for web service composition is introduced. The algorithm uses the proposed business relation model to minimize the searching space and uses the proposed goal distance as a heuristic rule. Compared with other algorithms tackling web service composition such as AI planning, the proposed algorithm focuses not only on how to convert the web service composition problem to the AI planning problem, but also exerts its effort on how to apply the business feature of web service composition into planning in order to improve the effectiveness. The experiment shows the better performance of the proposed algorithm. 展开更多
关键词 AI planning web service web service composition business relation model
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θ-improved limited tolerance relation model of incomplete information system for evaluation of water conservancy project management modernization 被引量:4
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作者 Yu-qin GAO Guo-hua FANG Ya-qin LIU 《Water Science and Engineering》 EI CAS CSCD 2013年第4期469-477,共9页
The modernization of water conservancy project management is a complicated engineering system involving a management system, a management method, management personnel, the exertion of social, economic, and ecological ... The modernization of water conservancy project management is a complicated engineering system involving a management system, a management method, management personnel, the exertion of social, economic, and ecological effects, and so on. However, indices for evaluating the modernization of water conservancy project management are usually unobtainable in practical applications. Conducting appropriate extension of the classical rough set theory and then applying it to an incomplete information system are the key to the application of the rough set theory Based on analysis of some extended rough set models in incomplete information systems, a rough set model based on the θ-improved limited tolerance relation is put forward. At the same time, upper approximation and lower approximation are defined under this improved relation. According to the evaluation index system and management practices, the threshold for θ is defined. An example study indicates the practicability and maneuverability of the model. 展开更多
关键词 Key words: modernization of water conservancy project management O-improved limitedtolerance relation model upper and lower approximations threshold
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On grey relation projection model based on projection pursuit 被引量:3
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作者 Wang Shuo Yang Shanlin Ma Xijun 《Engineering Sciences》 EI 2008年第4期49-52,共4页
Multidimensional grey relation projection value can be synthesized as one-dimensional projection value by using projection pursuit model. The larger the projection value is,the better the model. Thus,according to the ... Multidimensional grey relation projection value can be synthesized as one-dimensional projection value by using projection pursuit model. The larger the projection value is,the better the model. Thus,according to the projection value,the best one can be chosen from the model aggregation. Because projection pursuit modeling based on accelerating genetic algorithm can simplify the implementation procedure of the projection pursuit technique and overcome its complex calculation as well as the difficulty in implementing its program,a new method can be obtained for choosing the best grey relation projection model based on the projection pursuit technique. 展开更多
关键词 grey relation projection model projection pursuit real coded accelerating genetic algorithm identification coefficient objective weight
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Conducting a Correlation Model Between TCM Constitution and Physical Examination Index Based on BPNN Algorithm 被引量:3
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作者 Yue LUO Bing LIN +1 位作者 Chuan-Biao WEN Mao LUO 《Digital Chinese Medicine》 2018年第1期84-89,共6页
This paper studies the correlation between Traditional Chinese Medicine(TCM)Constitution discrimination and physical examination index based on BPNN algorithm.253cases of routine urine test were used to build a linkag... This paper studies the correlation between Traditional Chinese Medicine(TCM)Constitution discrimination and physical examination index based on BPNN algorithm.253cases of routine urine test were used to build a linkage model between TCM Constitution and physical indicators via BPNN algorithm.According to the test,the correct rate of learning and test group are60%and40%,respectively.A strong correlation was found between TCM Constitution and physical examination indexes.By applying cutting-edge knowledge and technologies,the development and modernization process of TCM can be greatly promoted. 展开更多
关键词 BPNN algorithm Constitution of TCM Physical examination target relational model Preventive treatment of disease
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Attitude control of spacecraft during propulsion of swing thruster 被引量:1
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作者 夏喜旺 荆武兴 +1 位作者 高长生 韦文书 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2012年第1期94-100,共7页
As for orbit transfer vehicle (OTV) with multiple satellites/payloads carried,the release of each payload will bring serious change to the mass center of OTV and the thrust produced by the swing thruster will form a r... As for orbit transfer vehicle (OTV) with multiple satellites/payloads carried,the release of each payload will bring serious change to the mass center of OTV and the thrust produced by the swing thruster will form a rather large disturbance to the attitude of OTV. Steering the nozzle to track the estimated center of mass (ECM) of OTV can reduce but not remove the disturbance due to the difference between the ECM and the practical mass center (PCM) of OTV. The practical propelling direction will change with the internal motion during the propulsion process and attitude control system should be enabled to guarantee that the propelling direction is collinear with the command. Since the structural parameters have changed,which is due to internal motion and fuel consumption,the dynamic model have to be formulated to determine these time-varying parameters and the required attitude of OTV should be determined as well. Modulating attitude quaternion results in quasi Euler angles. Based on the resulting quasi Euler angles,a novel attitude switching control law is introduced to control the variable-mass OTV. Simulation results show that,even in the case of structural asymmetry,control torque matrix asymmetry,attitude disturbance and strong coupling between the channels,the attitude of OTV can be controlled perfectly,and the proposed attitude control law is effective for the variable-mass OTV with swing thruster. 展开更多
关键词 variable-mass spacecraft relative motion dynamic modeling quasi Euler angle attitude switching control law
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Generalized δ-entropy condition to Riemann solution for Chaplygin gas in traffic flow 被引量:1
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作者 Wancheng SHENG Ying ZENG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2015年第3期353-364,共12页
The Riemann problem for the Aw-Rascle model in the traffic flow with the Delta initial data for the Chaplygin gas is studied. The solutions are constructed globally under the generalized Rankine-Hugoniot relations, t... The Riemann problem for the Aw-Rascle model in the traffic flow with the Delta initial data for the Chaplygin gas is studied. The solutions are constructed globally under the generalized Rankine-Hugoniot relations, the δ-entropy conditions, and the generalized δ-entropy conditions. A new Delta wave, which is called a primary Delta wave, is defined in some solutions. The primary Delta wave satisfies the generalized Rankine- Hugoniot relations and the generalized δ-entropy conditions. It generates initially from the Delta initial data, which either evaluates a Delta wave, whose weight becomes stronger and stronger, or disappears at a finite time. 展开更多
关键词 generalized δ-entropy condition Riemann problem for Aw-Rascle model generalized Rankine-Hugoniot relation Delta initial datum Chaplygin gas
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The rough representation and measurement of quotient structure in algebraic quotient space model 被引量:5
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作者 陈林书 Wang Jiayang 《High Technology Letters》 EI CAS 2017年第3期293-297,共5页
Granular computing is a very hot research field in recent years. In our previous work an algebraic quotient space model was proposed,where the quotient structure could not be deduced if the granulation was based on an... Granular computing is a very hot research field in recent years. In our previous work an algebraic quotient space model was proposed,where the quotient structure could not be deduced if the granulation was based on an equivalence relation. In this paper,definitions were given and formulas of the lower quotient congruence and upper quotient congruence were calculated to roughly represent the quotient structure. Then the accuracy and roughness were defined to measure the quotient structure in quantification. Finally,a numerical example was given to demonstrate that the rough representation and measuring methods are efficient and applicable. The work has greatly enriched the algebraic quotient space model and granular computing theory. 展开更多
关键词 granular computing algebraic quotient space model quotient structure upper(lower) congruence relation
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System failure analysis based on DEMATEL–ISM and FMECA 被引量:2
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作者 申桂香 孙曙光 +3 位作者 张英芝 王志琼 陈炳锟 马闯 《Journal of Central South University》 SCIE EI CAS 2014年第12期4518-4525,共8页
A new method of system failure analysis was proposed. First, considering the relationships between the failure subsystems,the decision making trial and evaluation laboratory(DEMATEL) method was used to calculate the d... A new method of system failure analysis was proposed. First, considering the relationships between the failure subsystems,the decision making trial and evaluation laboratory(DEMATEL) method was used to calculate the degree of correlation between the failure subsystems, analyze the combined effect of related failures, and obtain the degree of correlation by using the directed graph and matrix operations. Then, the interpretative structural modeling(ISM) method was combined to intuitively show the logical relationship of many failure subsystems and their influences on each other by using multilevel hierarchical structure model and obtaining the critical subsystems. Finally, failure mode effects and criticality analysis(FMECA) was used to perform a qualitative hazard analysis of critical subsystems, determine the critical failure mode, and clarify the direction of reliability improvement.Through an example, the result demonstrates that the proposed method can be efficiently applied to system failure analysis problems. 展开更多
关键词 system failure analysis related failure decision making and evaluation laboratory-interpretative structural modeling(DEMATEL-ISM) failure mode effects and criticality analysis(FMECA)
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AXIAL HEAT CONDUCTION MODEL TO PREDICT MAXIMUM HEAT REMOVE OF MINIATURE HEAT PIPE BASED ON GREY MODEL THEORY 被引量:3
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作者 Tsai Mengchang Chang Shinhsing Kang Shungwen 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2005年第4期477-481,共5页
Computer chip is always accompanied by the increase of heat dissipation and miniaturization. The miniature heat pipes are widely used in notebook computer to resolve the heat dissipation problems. Maximum heat removed... Computer chip is always accompanied by the increase of heat dissipation and miniaturization. The miniature heat pipes are widely used in notebook computer to resolve the heat dissipation problems. Maximum heat removed model of miniature heat pipes building by grey model is presented. In order to know the foundation for modeling, the smooth grade of error examination is inquired and the accuracy of grey relational grade is verified. The model can be used to select a suitable heat pipes to solve electric heat problems in the future. Final results show that the grey model only needs four experiment data and its error value is less than 10%, further, it is better than computational fluid dynamics (CFD) model. 展开更多
关键词 Maximum heat removed model Miniature heat pipe Grey model theory Computational fluid dynamics (CFD) Grey relational grade
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Study on Mandatory Access Control in a Secure Database Management System
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作者 ZHU Hong, FENG Yu cai School of Computer Science and Technology, Huazhong University of Science and Technology, Wuhan 430074, China 《Journal of Shanghai University(English Edition)》 CAS 2001年第4期299-307,共9页
This paper proposes a security policy model for mandatory access control in class B1 database management system whose level of labeling is tuple. The relation hierarchical data model is extended to multilevel relatio... This paper proposes a security policy model for mandatory access control in class B1 database management system whose level of labeling is tuple. The relation hierarchical data model is extended to multilevel relation hierarchical data model. Based on the multilevel relation hierarchical data model, the concept of upper lower layer relational integrity is presented after we analyze and eliminate the covert channels caused by the database integrity. Two SQL statements are extended to process polyinstantiation in the multilevel secure environment. The system is based on the multilevel relation hierarchical data model and is capable of integratively storing and manipulating multilevel complicated objects ( e.g., multilevel spatial data) and multilevel conventional data ( e.g., integer, real number and character string). 展开更多
关键词 multilevel relation hierarchical data model covert channels mandatory access control POLYINSTANTIATION hierarchical classification non hierarchical category security level multilevel relation hierarchical instance INTEGRITY cluster
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On the Relation Redundancy in Fuzzy Databases
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作者 唐晓辉 陈国青 《Journal of Donghua University(English Edition)》 EI CAS 2006年第6期67-70,83,共5页
This paper concentrates on the problem of data redundancy under the extended-possibility-based model. Based on the information gain in data classification, a measure - relation redundancy - is proposed to evaluate the... This paper concentrates on the problem of data redundancy under the extended-possibility-based model. Based on the information gain in data classification, a measure - relation redundancy - is proposed to evaluate the degree of a given relation being redundant in whole. The properties of relation redundancy are also investigated. This new measure is useful in dealing with data redundancy. 展开更多
关键词 fuzzy relational data model CLOSENESS relation redundancy.
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Research of storage technique for C-Temporal Relation Data Model
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作者 (Dept. of Computer & Engineering, Guangxi University of Technology, Guangxi Liuzhou 645006, China) WANG Zhi-wen (Mechanical Engineering College, Guangxi University, 530004, NanNin China )CAI Qi-xian, Wang Hu-Qi 《微计算机信息》 北大核心 2008年第9期273-275,共3页
As there is datum redundancy in tradition database and temporal database in existence and the quantities of temporal database are increasing fleetly. We put forward compress storage tactics for temporal datum which co... As there is datum redundancy in tradition database and temporal database in existence and the quantities of temporal database are increasing fleetly. We put forward compress storage tactics for temporal datum which combine compress technology in existence in order to settle datum redundancy in the course of temporal datum storage and temporal datum of slow acting domain and momentary acting domain are accessed by using each from independence clock method and mutual clock method .We also bring forward strategy of gridding storage to resolve the problems of temporal datum rising rapidly. 展开更多
关键词 Temporal Relation Data Model Datum redundancy Compress storage Independence clock method Mutual clock method Gridding Storage
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EFFECT OF SHS PARAMETERS OF Ni0.35Zn0.65Fe2O4 FERRITE ON MAGNETIC PROPERTIES AND ESTABLISHMENT OF MATHEMATICAL MODEL
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作者 Y. Li J. P. Zhao +1 位作者 H. M. Huang J. C. Han and S. Y. Du (Harbin Institute of Technology, Harbin 150001, China) 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2000年第2期821-824,共4页
Ni0.35Zn0.65Fe2O4 ferrite was synthesized by SHS method. In the process of SHS, combustion temperature and velocity were the main process parameters , which were decided by the Fe content, grain size of the ferrite po... Ni0.35Zn0.65Fe2O4 ferrite was synthesized by SHS method. In the process of SHS, combustion temperature and velocity were the main process parameters , which were decided by the Fe content, grain size of the ferrite powder, relative density and the oxygen pressure. In this paper the effects of Fe content, grain size and oxygen pressure on combustion temperature and velocity were discussed. The relation between combustion temperature and magnetic permeability was also studied and the method of polynomial regression was used to establish the mathematical model of the relation. 展开更多
关键词 combustion temperature combustion velocity Fe content relative density oxygen pressure mathematical model
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Estimation of the water–oil–gas relative permeability curve from immiscible WAG coreflood experiments using the cubic B-spline model
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作者 Dai-Gang Wang Yong-Le Hu +1 位作者 Jing-Jing Sun Yong Li 《Petroleum Science》 SCIE CAS CSCD 2016年第3期507-516,共10页
Immiscible water-alternating-gas(WAG) flooding is an EOR technique that has proven successful for water drive reservoirs due to its ability to improve displacement and sweep efficiency.Nevertheless,considering the c... Immiscible water-alternating-gas(WAG) flooding is an EOR technique that has proven successful for water drive reservoirs due to its ability to improve displacement and sweep efficiency.Nevertheless,considering the complicated phase behavior and various multiphase flow characteristics,gas tends to break through early in production wells in heterogeneous formations because of overriding,fingering,and channeling,which may result in unfavorable recovery performance.On the basis of phase behavior studies,minimum miscibility pressure measurements,and immiscible WAG coreflood experiments,the cubic B-spline model(CBM) was employed to describe the three-phase relative permeability curve.Using the Levenberg-Marquardt algorithm to adjust the vector of unknown model parameters of the CBM sequentially,optimization of production performance including pressure drop,water cut,and the cumulative gas-oil ratio was performed.A novel numerical inversion method was established for estimation of the water-oil-gas relative permeability curve during the immiscible WAG process.Based on the quantitative characterization of major recovery mechanisms,the proposed method was validated by interpreting coreflood data of the immiscible WAG experiment.The proposed method is reliable and can meet engineering requirements.It provides a basic calculation theory for implicit estimation of oil-water-gas relative permeability curve. 展开更多
关键词 Cubic B-spline model Immiscible WAG flooding Relative permeability Numerical inversion
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A new relative efficiency in parameter estimation for linear model
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作者 YANG Hu CHEN Zhu-liang 《Journal of Chongqing University》 CAS 2007年第2期141-145,共5页
A new relative efficiency of parameter estimation for generalized Gauss-Markov linear model was proposed. Its lower bound was also derived. Its properties were explored in comparison with three currently very popular ... A new relative efficiency of parameter estimation for generalized Gauss-Markov linear model was proposed. Its lower bound was also derived. Its properties were explored in comparison with three currently very popular relative efficiencies. The new relative efficiency not only reflects sensitively the error and loss caused by the substitution of the least square estimator for the best linear unbiased estimator, but also overcomes the disadvantage of weak dependence on the design matrix. 展开更多
关键词 linear model: narameter estimation: relative efficiency
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A New Model of China-US Big Power Relations: A Symbolic Sign in Foreign Affairs
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作者 Siyuan Huang 《International Relations and Diplomacy》 2016年第6期371-377,共7页
To cope with the current crisis and tensions full-filled China-US relationship, Chinese President Xi Jinping put forward the concept of building a new model of China-US big power relations, which the US agrees. Yet th... To cope with the current crisis and tensions full-filled China-US relationship, Chinese President Xi Jinping put forward the concept of building a new model of China-US big power relations, which the US agrees. Yet the new model won a heated discussion. In China this new model was evaluated positively and optimistically, while in the US it was perceived as a strategic challenge or even a threat. In the present article, the author proposes that this new model of China-US big power relations is more like a symbolic sign in foreign affairs rather than a strategic challenge or a threat or an effective and workable mechanism at this moment, and meanwhile analyses this view from diachronic and semiotic perspectives. The analyses reveal that the new model functions as a symbolic sign, signifying to the world that conceptually the two big powers have a good and harmonious relationship. 展开更多
关键词 a new model of China-US big power relations a symbolic sign diachronic perspective semioticperspective
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