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Nonlinear Dynamics Behaviors of a Rotor Roller Bearing System with Radial Clearances and Waviness Considered 被引量:16
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作者 王黎钦 崔立 +1 位作者 郑德志 古乐 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2008年第1期86-96,共11页
A rotor system supported by roller beatings displays very complicated nonlinear behaviors due to nonlinear Hertzian contact forces, radial clearances and bearing waviness. This paper presents nonlinear bearing forces ... A rotor system supported by roller beatings displays very complicated nonlinear behaviors due to nonlinear Hertzian contact forces, radial clearances and bearing waviness. This paper presents nonlinear bearing forces of a roller bearing under four-dimensional loads and establishes 4-DOF dynamics equations of a rotor roller bearing system. The methods of Newmark-β and of Newton-Laphson are used to solve the nonlinear equations. The dynamics behaviors of a rigid rotor system are studied through the bifurcation, the Poincar è maps, the spectrum diagrams and the axis orbit of responses of the system. The results show that the system is liable to undergo instability caused by the quasi-periodic bifurcation, the periodic-doubling bifurcation and chaos routes as the rotational speed increases. Clearances, outer race waviness, inner race waviness, roller waviness, damping, radial forces and unbalanced forces-all these bring a significant influence to bear on the system stability. As the clearance increases, the dynamics behaviors become complicated with the number and the scale of instable regions becoming larger. The vibration frequencies induced by the roller bearing waviness and the orders of the waviness might cause severe vibrations. The system is able to eliminate non-periodic vibration by reasonable choice and optimization of the parameters. 展开更多
关键词 roller bearing rotor system nonlinear bearing force dynamics behaviors BIFURCATION CHAOS
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CHEMICAL BEHAVIOR OF CERIUM ELEMENT IN ROCK WEATHERING SYSTEM 被引量:10
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作者 Chi, Ru'an Zhu, Guocai +1 位作者 Zhang, Ping Xu, Yinghui 《中国有色金属学会会刊:英文版》 EI CSCD 1999年第1期160-166,共7页
1INTRODUCTIONTheelectronicstructureofgroundstateatomceriumisXe4f15d16s2,andtheelectronicstructureoftrivalent... 1INTRODUCTIONTheelectronicstructureofgroundstateatomceriumisXe4f15d16s2,andtheelectronicstructureoftrivalentoxidizingstateisX... 展开更多
关键词 CERIUM rare earth ORE WEATHERING system CHEMICAL behavior
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Dynamic Behavior of Two Part Towing Cable System During Turning 被引量:3
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作者 GAO Hui WANG Zhibo 《Journal of Shanghai Jiaotong university(Science)》 EI 2018年第3期444-455,共12页
An improved numerical method is used to simulate the dynamic behavior of a two part towing cable systems during turnings. In U turns and full turns, periodical heave motions are found both for the towed vehicle and fo... An improved numerical method is used to simulate the dynamic behavior of a two part towing cable systems during turnings. In U turns and full turns, periodical heave motions are found both for the towed vehicle and for the depressor. Periodic motions of the subsea units and of the cable surface tension are closely related to the turning parameters, such as turning velocity and turning radius. System parameters, such as length of the second cable and the vehicle bydrodynamics, also damp turning instability. 展开更多
关键词 towing cable systems dynamic behavior periodic motion turning operation
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Study on Behavior Model in Open Architecture CNC System 被引量:1
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作者 王宇晗 吴祖育 +1 位作者 陆志强 蔡建国 《Journal of China Textile University(English Edition)》 EI CAS 1999年第4期52-55,共4页
Since a CNC controller has different real-time require-ments in difference levels,proper methods for dynamicmodeling must be employed when a CNC controller isdesigned.Based on behavior model in this paper,a newdynamic... Since a CNC controller has different real-time require-ments in difference levels,proper methods for dynamicmodeling must be employed when a CNC controller isdesigned.Based on behavior model in this paper,a newdynamic modeling method is given and used to analyzethe life cycle of application objects and their interactionsin an open architecture CNC controller modeling.Be-sides,the paper develop a solution how to realize recon-figurable structures in CNC systems and seamless con-nection between fuuction modules and system. 展开更多
关键词 CNC system MODEL behavior MODEL ttate MACHINE
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A Hybrid Intrusion Detection System for Smart Home Security Based on Machine Learning and User Behavior 被引量:1
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作者 Faisal Alghayadh Debatosh Debnath 《Advances in Internet of Things》 2021年第1期10-25,共16页
With technology constantly becoming present in people’s lives, smart homes are increasing in popularity. A smart home system controls lighting, temperature, security camera systems, and appliances. These devices and ... With technology constantly becoming present in people’s lives, smart homes are increasing in popularity. A smart home system controls lighting, temperature, security camera systems, and appliances. These devices and sensors are connected to the internet, and these devices can easily become the target of attacks. To mitigate the risk of using smart home devices, the security and privacy thereof must be artificially smart so they can adapt based on user behavior and environments. The security and privacy systems must accurately analyze all actions and predict future actions to protect the smart home system. We propose a Hybrid Intrusion Detection (HID) system using machine learning algorithms, including random forest, X gboost, decision tree, K -nearest neighbors, and misuse detection technique. 展开更多
关键词 Anomaly Detection Smart Home systems behavioral Patterns SECURITY Threats
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Research on Open Block's Pedestrian System Based on the EnvironmentBehavior Theory: A Case Study of Shenzhen Oct-loft 被引量:1
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作者 LIN Jingwei ZHANG Yinan 《Journal of Landscape Research》 2017年第4期17-21,28,共6页
In the context of banning gated communities, blocks returning to the human-oriented scale become the new normal, and pedestrian system design will be paid more attention in the urban planning field. Oct-Loft Creative ... In the context of banning gated communities, blocks returning to the human-oriented scale become the new normal, and pedestrian system design will be paid more attention in the urban planning field. Oct-Loft Creative Park is a template for open blocks in Shenzhen, with a convenient and humanized pedestrian system. This paper selects the creative park's pedestrian system as the research object, using the environment-behavior theory for analysis. Finally, optimization strategies of pedestrian system will be put forward. 展开更多
关键词 SHENZHEN OCT-Loft Open blocks Pedestrian system Environment-behavior
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Vaporization behavior of lead from the FeO-CaO-SiO_2-Al_2O_3 slag system 被引量:3
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作者 Yanling Zhang Rui Zhang +1 位作者 Eiki Kasai Shiqi Li 《Journal of University of Science and Technology Beijing》 CSCD 2008年第6期671-677,共7页
Vaporization behavior (1163-1463 K) of lead in the slag system of FeO-CaO-SiO2-Al2O3 with CaC% was examined. A thermodynamic estimation with the principle of Gibbs free energy minimization showed that the major vapo... Vaporization behavior (1163-1463 K) of lead in the slag system of FeO-CaO-SiO2-Al2O3 with CaC% was examined. A thermodynamic estimation with the principle of Gibbs free energy minimization showed that the major vapor species from the sample of the FeO-CaO-SiO2-Al2O3 system+PbO+CaCl2 were metallic Pb, PbCl, PbCl2, and FeCl2, at the experimental temperature range. The experimental results show that the mole ratio of vaporized Cl in lead chlorides to vaporized Pb, simply expressed as Cl/Pb decreases with increasing temperature. The larger Cl/Pb means a larger ratio of gaseous PbCl2, since metallic Pb and PbCl vapors are formed in a similar reduction atmosphere. The evaporation is initially rapid and becomes steady after holding for 10 min. Gaseous PbCl2 is mainly formed during the heating period, and at the holding stage, it reacts with FeO to produce gaseous FeCl2 With regard to slag composition, FeO content and basicity significantly affect the evaporation of lead. High FeO content and high basicity promotes the formation of metallic Pb and PbCI, whereas, it prohibits PbCl2 evaporation. 展开更多
关键词 slag system smelting process vaporization behavior LEAD
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An Event Alarm System Based on Single and Group Human Behavior Analysis 被引量:1
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作者 Hung-Yu Yeh I-Cheng Chang Yung-Hsin Chen 《Journal of Electronic Science and Technology》 CAS CSCD 2017年第2期123-132,共10页
Due to the increasing demand for security, the development of intelligent surveillance systems has attracted considerable attention in recent years. This study aims to develop a system that is able to identify whether... Due to the increasing demand for security, the development of intelligent surveillance systems has attracted considerable attention in recent years. This study aims to develop a system that is able to identify whether or not the people need help in a public place. Different from previous work, our work considers not only the behaviors of the target person but also the interaction between him and nearby people. In the paper, we propose an event alarm system which can detect the human behaviors and recognize the happening event through integrating the results generated from the single and group behavior analysis. Several new effective features are proposed in the study. Besides, a mechanism capable of extracting one-to-one and multiple-to-one relations is also developed. Experimental results show that the proposed approach can correctly detect human behaviors and provide the alarm messages when emergency events occur. 展开更多
关键词 Index Terms Event alarm system group behavior analysis human behavior recognition single behavior analysis stooping curve.
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Modeling Method for Flexible Energy Behaviors in CNC Machining Systems 被引量:4
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作者 Yu-Feng Li Yu-Lin Wang +2 位作者 Yan He Yan Wang Shen-Long Lin 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2018年第1期156-166,共11页
CNC machining systems are inevitably confronted with frequent changes in energy behaviors because they are widely used to perform various machining tasks. It is a challenge to understand and analyze the flexible energ... CNC machining systems are inevitably confronted with frequent changes in energy behaviors because they are widely used to perform various machining tasks. It is a challenge to understand and analyze the flexible energy behaviors in CNC machining systems. A method to model flexible energy behaviors in CNC machining systems based on hierarchical objected-oriented Petri net(HOONet) is proposed. The structure of the HOONet is constructed of a high-level model and detail models. The former is used to model operational states for CNC machining systems, and the latter is used to analyze the component models for operational states. The machining parameters having great impacts on energy behaviors in CNC machining systems are declared with the data dictionary in HOONet models. A case study based on a CNC lathe is presented to demonstrate the proposed modeling method. The results show that it is effective for modeling flexible energy behaviors and providing a fine-grained description to quantitatively analyze the energy consumption of CNC machining systems. 展开更多
关键词 Energy behaviors CNC machining systems Modeling method HOONet
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Vehicles, Advanced Features, Driver Behavior, and Safety: A Systematic Review of the Literature 被引量:1
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作者 Raghuveer Prasad Gouribhatla Srinivas Subrahmanyam Pulugurtha 《Journal of Transportation Technologies》 2022年第3期420-438,共19页
Driver errors contribute to more than 94% of traffic crashes. Automotive companies are striving to enhance their vehicles to eliminate driver errors and reduce the number of crashes. Various advanced features like lan... Driver errors contribute to more than 94% of traffic crashes. Automotive companies are striving to enhance their vehicles to eliminate driver errors and reduce the number of crashes. Various advanced features like lane departure warning (LDW), blind spot warning (BSW), over speed warning (OSW), forward collision warning (FCW), lane keep assist (LKA), adaptive cruise control (ACC), cooperative ACC (CACC), and automated emergency braking (AEB) are designed to assist with, or in some cases take over, certain driving maneuvers. They can be broadly categorized into advanced driver assistance system (ADAS) and automated features. Each of these advanced features focuses on addressing a particular task of driving, thereby, aiding the driver, influencing their behavior, and enhancing safety. Many vehicles with these advanced features are penetrating into the market, yet the total reported number of crashes has increased in recent years. This paper presents a systematic review of these advanced features on driver behavior and safety. The review is categorized into 1) survey and mathematical methods to assess driver behavior, 2) field test methods to assess driver behavior, 3) microsimulation methods to assess driver behavior, 4) driving simulator methods to assess driver behavior, and 5) driver understanding and the effectiveness of advanced features. It is followed by conclusions, knowledge gaps, and need for further research. 展开更多
关键词 Vehicle Advanced Driver Assistance system AUTOMATED DRIVER behavior SAFETY
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A System Status Definition to Improve Behavior Description in Specifications Based on Constructal Law
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作者 Luciano Ondir Freire Dr. Delvonei Alves de Andrade Daniel Monterrain 《Open Journal of Applied Sciences》 2018年第8期315-337,共23页
System behavior description using states faces problems like state explosion, lack of clear definition of state, state identification and coordination between multiple agents. The goals of this work are to ease design... System behavior description using states faces problems like state explosion, lack of clear definition of state, state identification and coordination between multiple agents. The goals of this work are to ease design activity, to reduce engineering efforts, and to mitigate project risks. The proposed way is to improve information flow during design by adding definitions and some protocols or rules for communicating a specification or design description. This work presented an objective definition of system status (way of interaction with the rest of the world) along other concepts. This work focused in definitions as mind entities and their importance to rationalize work and mitigate project risks during design. This article presented some simple examples to illustrate the advantages of each aspect of proposed definition of system status and discussed limits and exceptions for such definition. The key finding was the proposed definition which was the simplest while keeping completeness at a given product breakdown level. Such definition of status enforced formal segregation of needs and solutions, and eased the inclusion of behavior definition in specifications. 展开更多
关键词 CYBER systems system Design CONSTRUCTAL LAW system behavior Modelling State Analysis system Engineering
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EXISTENCE AND BLOW-UP BEHAVIOR OF CONSTRAINED MINIMIZERS FOR SCHRDINGER-POISSON-SLATER SYSTEM 被引量:1
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作者 朱新才 《Acta Mathematica Scientia》 SCIE CSCD 2018年第2期733-744,共12页
In this article, we study constrained minimizers of the following variational problem ε(p):={u∈H1 inf(R3),||u||22=p} E(u),ρ〉0,where E(u) is the SchrSdinger-Poisson-Slater (SPS) energy functional E(... In this article, we study constrained minimizers of the following variational problem ε(p):={u∈H1 inf(R3),||u||22=p} E(u),ρ〉0,where E(u) is the SchrSdinger-Poisson-Slater (SPS) energy functional E(u):1/2∫R3|△u(x)|2dx-1/4∫R3∫R3u2(y)u2(x)/|x-y|dydx-1/p∫R3|u(x)∫pdx in R3,and p ∈ (2,6). We prove the existence of minimizers for the cases 2 〈 p 〈10/3, p 〉 0, and P =10/3, 0 〈 p 〈 p*, and show that e(ρ) = -∞ for the other cases, where p* = ||φ||22 and φ(x) is the unique (up to translations) positive radially symmetric solution of -△u + u = u7/3 in R3. Moreover, when e(ρ*) = -∞, the blow-up behavior of minimizers as p/p* is also analyzed rigorously. 展开更多
关键词 SchrSdinger-Poisson-Slater system constrained minimizer blow-up behavior
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A Comparison of the Influence of World Views and Value Systems on Behavior between Chinese and Americans
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作者 李启宇 《海外英语》 2016年第23期170-172,共3页
This thesis compares the differences between Chinese and Americans in terms of their world view and value systems,and analyzes how these differences affect the behavioral patterns of people with different cultural bac... This thesis compares the differences between Chinese and Americans in terms of their world view and value systems,and analyzes how these differences affect the behavioral patterns of people with different cultural backgrounds. It also proposes some suggestions to overcome the difference. As globalization is quickening its pace, world views and value systems, as the core of culture, profoundly affect people's pattern of behavior. A deeper understanding and consciousness of the differences may promote a more effective communication between different cultural backgrounds. This thesis compares the differences between Chinese and US cultures from three perspectives: the different world view between Chinese and Americans, the different value systems between Chinese and Americans and how the two affect their behaviors. And some suggestions are also given. 展开更多
关键词 world view value system behavior
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Residential Electricity Consumption Behavior Mining Based on System Cluster and Grey Relational Degree
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作者 Mengjia Xu Yuhong Wang 《Energy and Power Engineering》 2017年第4期390-400,共11页
In order to improve the utilization of the residential electricity consumption data which contains the information on the user’s electricity consumption habits, a residential electricity consumption behaviors mining ... In order to improve the utilization of the residential electricity consumption data which contains the information on the user’s electricity consumption habits, a residential electricity consumption behaviors mining algorithm model is constructed. Firstly, according to the attribute, the collected data can be divided into the global data and the phase data, then the appropriate global variables are selected to mine the user’s electricity consumption patterns in the near future on the system clustering algorithm. Based on the theory of grey relational analysis, combing phase data with the power modes to analyze the potential characteristics of residential electricity consumption behaviors deeply that verify the ability of latest power mode to predict household electricity consumption situation in the coming few days and the effect of dominant phase variables on the peak load shifting. Finally, from the actual data of a certain family, the proposed data mining algorithm is testified that it can effectively explore the electricity consumption behavior habits and characteristics of the family. 展开更多
关键词 Data Mining ELECTRICITY Consumption behavior system CLUSTER GREY RELATIONAL Degree
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Chaotic behaviors of the (2+1)-dimensional generalized Breor-Kaup system 被引量:6
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作者 马松华 方建平 +1 位作者 任清褒 杨征 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第5期140-144,共5页
With the help of the Maple symbolic computation system and the projective equation approach,a new family of variable separation solutions with arbitrary functions for the(2+1)-dimensional generalized Breor-Kaup(GB... With the help of the Maple symbolic computation system and the projective equation approach,a new family of variable separation solutions with arbitrary functions for the(2+1)-dimensional generalized Breor-Kaup(GBK) system is derived.Based on the derived solitary wave solution,some chaotic behaviors of the GBK system are investigated. 展开更多
关键词 projective equation approach generalized Breor Kaup system variable separation solu-tion chaotic behavior
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LONG-TIME BEHAVIOR OF TRANSIENT SOLUTIONS FOR CELLULAR NEURAL NETWORK SYSTEMS
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作者 蒋耀林 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2000年第3期321-326,共6页
By establishing concept an transient solutions of general nonlinear systems converging to its equilibrium set, long-time behavior of solutions for cellular neural network systems is studied. A stability condition in g... By establishing concept an transient solutions of general nonlinear systems converging to its equilibrium set, long-time behavior of solutions for cellular neural network systems is studied. A stability condition in generalized sense is obtained. This result reported has an important guide to concrete neural network designs. 展开更多
关键词 dynamic stability cellular neural network systems long-time behavior of transient solutions
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Effects of interfacial discontinuity on the fracture behavior in the superconductor-substrate system
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作者 Lang Jiang Xiaoqiang Ren +1 位作者 Zhiwen Gao Youhe Zhou 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2019年第1期43-49,I0004,共8页
This study concerns a two-dimensional model and the corresponding virtual crack closure technique(VCCT) implemented to solve the general boundary value problems that may explain why interface discontinuity has effects... This study concerns a two-dimensional model and the corresponding virtual crack closure technique(VCCT) implemented to solve the general boundary value problems that may explain why interface discontinuity has effects on the fracture behavior in the superconductor-substrate system. The interfacial discontinuity can be classified according to the material properties' continuity and their derivatives' continuity at the interface. For nonhomogeneous superconductor and substrate specimens with various material properties, a VCCT method is developed to calculate their fracture behavior. Furthermore, the effects of applied magnetic field amplitude and nonhomogeneous parameters are extensively and parametrically studied in two activation processes(zero-field cooling and field cooling). The integrative and computational study presented here provide a fundamental mechanistic understanding of the fracture mechanism in the superconductor-substrate system and sheds light on the rational design of interfacial continuity. 展开更多
关键词 Superconductor-substrate system INTERFACIAL DISCONTINUITY Fracture behavior Activation processes
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Conversion of Object Oriented System into Software Product Line with Delta Modeling Abstract Behavioral Specification
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作者 Ricky Timothy Gultom Maya Retno Ayu Setyautami Iis Solichah 《Journal of Computer and Communications》 2014年第2期85-90,共6页
This article contains a system conversion from object oriented design into Software Product Line (SPL) using delta modeling of Abstract Behavioral Specification (ABS). ABS is a modeling language which targets system w... This article contains a system conversion from object oriented design into Software Product Line (SPL) using delta modeling of Abstract Behavioral Specification (ABS). ABS is a modeling language which targets system with high level of variety and supports SPL development with delta modeling. The case study of this thesis is a digital library system called Library Automation and Digital Archive (LONTAR). Originally, LONTAR only uses SOAP-based web service. With ABS, LONTAR will be converted into SPL and implement another web service called REST. The motivation of this conversion of LONTAR from object oriented into SPL is because it is easier to develop system with ABS than using regular object oriented. Product definition in ABS is relatively easier than creating a new subclass and do customization to make it works well. 展开更多
关键词 system CONVERSION ABSTRACT behaviorAL SPECIFICATION DELTA MODELING Software Product line Object Oriented
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Embed-Solitons and Their Evolutional Behaviors of (3+1)-Dimensional Burgers System
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作者 ZHU Hai-Ping ZHENG Chun-Long College of Mathematics and Physics,Lishui University,Zhejiang 323000,China2 Shanghai Institute of Applied Mathematics and Mechanics,Shanghai University,Shanghai 200072,China 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第7期57-62,共6页
With the help of an extended mapping approach and a linear variable separation method,new families ofvariable separation solutions with arbitrary functions for the(3+1)-dimensional Burgers system are derived.Based ont... With the help of an extended mapping approach and a linear variable separation method,new families ofvariable separation solutions with arbitrary functions for the(3+1)-dimensional Burgers system are derived.Based onthe derived exact solutions, some novel and interesting localized coherent excitations such as embed-solitons are revealedby selecting appropriate boundary conditions and/or initial qualifications.The time evolutional properties of the novellocalized excitation are also briefly investigated. 展开更多
关键词 extended mapping method (3+1)-dimensional Burgers system embed-soliton evolutional behavior
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