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KD(D&K) and Double-Bases Cooperating Mechanism 被引量:7
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作者 Yang Bingru(School of information Engineering,University of Science and Technology of BeiJing,100083, P. R. China)Xiong Fanlun(The institute of Intelligent Machine, Academic Sinica,Hefei 230031, P. R. China) 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1999年第2期48-54,共7页
KD(D&K) (Synthesized Knowledge Discovery System based on Database and KnowledgeBase Cooperating Mechanism) is first advanced in this paper on the basis of KDD (KnowledgeDiscovery System based on Database) and KDK ... KD(D&K) (Synthesized Knowledge Discovery System based on Database and KnowledgeBase Cooperating Mechanism) is first advanced in this paper on the basis of KDD (KnowledgeDiscovery System based on Database) and KDK (Knowledge Discovery System based on KnowledgeBase). KD (D&K) is not simple addition of KDD and KDK but a new system with absolutelynew character and essential development, which is distinct from KDD and KDK and includes them.Not only the generalized structural frame of control rules KD (D&K) acquiring method is proposed,but also the theoretical basis of its key technical problem--don ble-bases cooperating mechanism isdiscussed according to the original academic idea to restrict KDD by basic knowledge base. 展开更多
关键词 Knowledge discovery General structure cooperating mechanism.
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KDD Based on Double-Base Cooperating Mechanism and Its Realization of Software 被引量:3
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作者 Yang Bingru & Shen Jiangtao(Information Engineering School, University of Science and Technology, Beijing100083, P. R. China) 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1999年第4期1-9,共9页
On the basis of KDD(Knowledge Discovery based on Database), this paper proposesthe general framework of open KDD system, discusses its theoretical foundation and realization of technology of its key technology-double ... On the basis of KDD(Knowledge Discovery based on Database), this paper proposesthe general framework of open KDD system, discusses its theoretical foundation and realization of technology of its key technology-double base cooperating mechanism, and especially introduces themining method of cause-and-effect rule. The result of initial illustration shows that the structure ofKDD is effective and available. 展开更多
关键词 Knowledge discovery cooperating mechanism General framework Cause statistic induction.
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Global asymptotic stability of positive equilibrium in a 3-species cooperating model with time delay
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作者 王长有 《Journal of Chongqing University》 CAS 2007年第3期192-199,共8页
The asymptotic behavior of the time-dependent solution for a 3-species cooperating model was investigated with the effects of both diffusion and time delay taken into consideration. We proved the global asymptotic sta... The asymptotic behavior of the time-dependent solution for a 3-species cooperating model was investigated with the effects of both diffusion and time delay taken into consideration. We proved the global asymptotic stability of a positive steady-state solution to the model problem by using coupled upper and lower solutions for a more general reaction-diffusion system that gives a common framework for 3-species cooperating model problems. The result of global asymptotic stability implies that the model system coexistence is permanent. Some global asymptotic stability results for 2-species cooperating reaction-diffusion systems are included in the discussion, and some known results are extended. 展开更多
关键词 3-species cooperating model asymptotic stability time delay positive equilibrium
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Allied Signal Inc.Cooperating with China's Auto Industry
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作者 Wu Wei 《China's Foreign Trade》 1994年第10期56-56,共1页
The Beijing American Allied Signal Inc. Auto Division announced in Beijing in June that it will invest about US$100 million in expanding cooperation with China’s auto industry. Allied Signal Inc. is a leading manufac... The Beijing American Allied Signal Inc. Auto Division announced in Beijing in June that it will invest about US$100 million in expanding cooperation with China’s auto industry. Allied Signal Inc. is a leading manufacturer providing worldwide service in aero-space, auto, chemicals, 展开更多
关键词 AUTO US WILL Allied Signal Inc.cooperating with China’s Auto Industry AASI
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Dual Dynamic PTZ Tracking Using Cooperating Cameras
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作者 Mohammed A. Eslami John R. Rzasa +1 位作者 Stuart D. Milner Christopher C. Davis 《Intelligent Control and Automation》 2015年第1期45-54,共10页
This paper presents a real-time, dynamic system that uses high resolution gimbals and motorized lenses with position encoders on their zoom and focus elements to “recalibrate” the system as needed to track a target.... This paper presents a real-time, dynamic system that uses high resolution gimbals and motorized lenses with position encoders on their zoom and focus elements to “recalibrate” the system as needed to track a target. Systems that initially calibrate for a mapping between pixels of a wide field of view (FOV) master camera and the pan-tilt (PT) settings of a steerable narrow FOV slave camera assume that the target is travelling on a plane. As the target travels through the FOV of the master camera, the slave cameras PT settings are then adjusted to keep the target centered within its FOV. In this paper, we describe a system we have developed that allows both cameras to move and extract the 3D coordinates of the target. This is done with only a single initial calibration between pairs of cameras and high-resolution pan-tilt-zoom (PTZ) platforms. Using the information from the PT settings of the PTZ platform as well as the precalibrated settings from a preset zoom lens, the 3D coordinates of the target are extracted and compared to those of a laser range finder and static-dynamic camera pair accuracies. 展开更多
关键词 SURVEILLANCE PTZ Cameras cooperating Cameras
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OPTIMAL DYNAMIC LOAD DISTRIBUTION OF MULTIPLE COOPERATING ROBOT MANIPULATORS 被引量:1
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作者 Zhao Yongsheng Huang Zhen Gao Feng(Yanshan University) 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 1994年第2期108-111,共17页
For the situation of multiple cooperating manipulators handling a single object,an equilibrium equation is presented in which the manipulator dynamics and control forces/torques are taken into account,and a expression... For the situation of multiple cooperating manipulators handling a single object,an equilibrium equation is presented in which the manipulator dynamics and control forces/torques are taken into account,and a expression is derived to allow the optimal dynamic load distribution of the combined system can be made. 展开更多
关键词 Multiple cooperating robot manipulators Optimal distribution Dynamic coordinate
全文增补中
NEW APPROACHES FOR COMPUTING DYNAMIC LOAD-CARRYING CAPACITY OF MULTIPLE COOPERATING ROBOTIC MANIPULATORS
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作者 Yang Yulin Lu Ling Zhao Yongsheng Zhou Yulin Yanshan University 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 1998年第2期67-72,共6页
A novel unified method for computing the dynamic load carrying capacity(DLCC) of multiple cooperating robotic manipulators is developed.In this method,the kinematic constraints and the governing dynamic equations of ... A novel unified method for computing the dynamic load carrying capacity(DLCC) of multiple cooperating robotic manipulators is developed.In this method,the kinematic constraints and the governing dynamic equations of the multiple robot system are formulated in the joint space by using the method of transference of dependence from one set of generalized coordinates to another,and the virtual work principle,which includes the readily available dynamics and joint torques of individual manipulators,and the dynamic of payload.Based on this dynamic model,the upper limit of the DLCC at any points on a given trajectory is obtained by solving a small size linear programming problem.This method is conceptually straightforward,and it is applicable also to the cases of multi fingered robot hands and multi legged walking machines. 展开更多
关键词 Robotic manipulators cooperating DYNAMICS Load carrying capacity
全文增补中
Communication Resource-Efficient Vehicle Platooning Control With Various Spacing Policies 被引量:2
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作者 Xiaohua Ge Qing-Long Han +1 位作者 Xian-Ming Zhang Derui Ding 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第2期362-376,共15页
Platooning represents one of the key features that connected automated vehicles may possess as it allows multiple automated vehicles to be maneuvered cooperatively with small headways on roads. However, a critical cha... Platooning represents one of the key features that connected automated vehicles may possess as it allows multiple automated vehicles to be maneuvered cooperatively with small headways on roads. However, a critical challenge in accomplishing automated vehicle platoons is to deal with the effects of intermittent and sporadic vehicle-to-vehicle data transmissions caused by limited wireless communication resources. This paper addresses the co-design problem of dynamic event-triggered communication scheduling and cooperative adaptive cruise control for a convoy of automated vehicles with diverse spacing policies. The central aim is to achieve automated vehicle platooning under various gap references with desired platoon stability and spacing performance requirements, while simultaneously improving communication efficiency. Toward this aim, a dynamic event-triggered scheduling mechanism is developed such that the intervehicle data transmissions are scheduled dynamically and efficiently over time. Then, a tractable co-design criterion on the existence of both the admissible event-driven cooperative adaptive cruise control law and the desired scheduling mechanism is derived. Finally, comparative simulation results are presented to substantiate the effectiveness and merits of the obtained results. 展开更多
关键词 Automated vehicles constant time headway spacing constant spacing cooperative adaptive cruise control event-triggered communication vehicle platooning
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Cooperative UAV search strategy based on DMPC-AACO algorithm in restricted communication scenarios 被引量:1
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作者 Shiyuan Chai Zhen Yang +3 位作者 Jichuan Huang Xiaoyang Li Yiyang Zhao Deyun Zhou 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期295-311,共17页
Improvement of integrated battlefield situational awareness in complex environments involving dynamic factors such as restricted communications and electromagnetic interference(EMI)has become a contentious research pr... Improvement of integrated battlefield situational awareness in complex environments involving dynamic factors such as restricted communications and electromagnetic interference(EMI)has become a contentious research problem.In certain mission environments,due to the impact of many interference sources on real-time communication or mission requirements such as the need to implement communication regulations,the mission stages are represented as a dynamic combination of several communication-available and communication-unavailable stages.Furthermore,the data interaction between unmanned aerial vehicles(UAVs)can only be performed in specific communication-available stages.Traditional cooperative search algorithms cannot handle such situations well.To solve this problem,this study constructed a distributed model predictive control(DMPC)architecture for a collaborative control of UAVs and used the Voronoi diagram generation method to re-plan the search areas of all UAVs in real time to avoid repetition of search areas and UAV collisions while improving the search efficiency and safety factor.An attention mechanism ant-colony optimization(AACO)algorithm is proposed for UAV search-control decision planning.The search strategy is adaptively updated by introducing an attention mechanism for regular instruction information,a priori information,and emergent information of the mission to satisfy different search expectations to the maximum extent.Simulation results show that the proposed algorithm achieves better search performance than traditional algorithms in restricted communication constraint scenarios. 展开更多
关键词 Unmanned aerial vehicles(UAV) Cooperative search Restricted communication Mission planning DMPC-AACO
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Effect of distribution of fines on evolution of cooperation in spatial public goods game
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作者 Xing-Ping Sun Yan-Zheng Bi +2 位作者 Hong-Wei Kang Yong Shen Qing-Yi Chen 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第9期239-245,共7页
In the realm of public goods game,punishment,as a potent tool,stands out for fostering cooperation.While it effectively addresses the first-order free-rider problem,the associated costs can be substantial.Punishers in... In the realm of public goods game,punishment,as a potent tool,stands out for fostering cooperation.While it effectively addresses the first-order free-rider problem,the associated costs can be substantial.Punishers incur expenses in imposing sanctions,while defectors face fines.Unfortunately,these monetary elements seemingly vanish into thin air,representing a loss to the system itself.However,by virtue of the redistribution of fines to cooperators and punishers,not only can we mitigate this loss,but the rewards for these cooperative individuals can be enhanced.Based upon this premise,this paper introduces a fine distribution mechanism to the traditional pool punishment model.Under identical parameter settings,by conducting a comparative experiment with the conventional punishment model,the paper aims to investigate the impact of fine distribution on the evolution of cooperation in spatial public goods game.The experimental results clearly demonstrate that,in instances where the punishment cost is prohibitively high,the cooperative strategies of the traditional pool punishment model may completely collapse.However,the model enriched with fine distribution manages to sustain a considerable number of cooperative strategies,thus highlighting its effectiveness in promoting and preserving cooperation,even in the face of substantial punishment cost. 展开更多
关键词 PUBLIC GOODS GAME FINE distribution COOPERATION
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Multi-UAV cooperative maneuver decision-making for pursuitevasion using improved MADRL
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作者 Delin Luo Zihao Fan +1 位作者 Ziyi Yang Yang Xu 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第5期187-197,共11页
Aiming at the problem of multi-UAV pursuit-evasion confrontation, a UAV cooperative maneuver method based on an improved multi-agent deep reinforcement learning(MADRL) is proposed. In this method, an improved Comm Net... Aiming at the problem of multi-UAV pursuit-evasion confrontation, a UAV cooperative maneuver method based on an improved multi-agent deep reinforcement learning(MADRL) is proposed. In this method, an improved Comm Net network based on a communication mechanism is introduced into a deep reinforcement learning algorithm to solve the multi-agent problem. A layer of gated recurrent unit(GRU) is added to the actor-network structure to remember historical environmental states. Subsequently,another GRU is designed as a communication channel in the Comm Net core network layer to refine communication information between UAVs. Finally, the simulation results of the algorithm in two sets of scenarios are given, and the results show that the method has good effectiveness and applicability. 展开更多
关键词 Reinforcement learning UAV Maneuver decision GRU Cooperative control
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An integrated MINLP model for multi-party coordination in downstream oil supply chain
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作者 Rui Qiu Bo Zhang +4 位作者 Wei Zhao Ren-Fu Tu Man-Qiu He Qi Liao Yong-Tu Liang 《Petroleum Science》 SCIE EI CAS CSCD 2024年第3期2066-2079,共14页
Cooperation among enterprises can bring overall and individual performance improvement,and a smooth coordination method is indispensable.However,due to the lack of customized coordination methods,cooperation in the do... Cooperation among enterprises can bring overall and individual performance improvement,and a smooth coordination method is indispensable.However,due to the lack of customized coordination methods,cooperation in the downstream oil supply chain cannot be carried out smoothly.This paper intends to propose a multi-party coordination method to promote cooperation between oil shippers and pipeline operator by optimizing oil transportation,oil substitution and pipeline pricing schemes.An integrated game-theoretic modeling and analysis approach is developed to characterize the operation behaviors of all stakeholders in the downstream oil supply chain.The proposed mixed integer nonlinear programming model constrains supply and demand capacity,transportation routes,oil substitution rules and pipeline freight levels.Logarithm transformation and price discretization are introduced for model linear approximation.Simulation experiments are carried out in the oil distribution system in South China.The results show that compared to the business-as-usual scheme,the new scheme saves transportation cost by 3.48%,increases pipeline turnover by 5.7%,and reduces energy consumption and emissions by 7.66%and 6.77%.It is proved that the proposed method improves the revenue of the whole system,achieves fair revenue distribution,and also improves the energy and environmental benefits of the oil supply chain. 展开更多
关键词 Downstreamoil supplychain Multi-partycoordination Cooperative game Mixed integernonlinear programming MODEL Pipeline transportation Revenue distribution
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Discreet investors exert greater influence on cooperation in the public goods game
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作者 康洪炜 金展瑶 +4 位作者 李明远 旺咩 孙兴平 沈勇 陈清毅 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期170-178,共9页
This paper studies the evolutionary process of cooperative behavior in a public goods game model with heterogeneous investment strategies in square lattices.In the proposed model,players are divided into defectors,coo... This paper studies the evolutionary process of cooperative behavior in a public goods game model with heterogeneous investment strategies in square lattices.In the proposed model,players are divided into defectors,cooperators and discreet investors.Among these,defectors do not participate in investing,discreet investors make heterogeneous investments based on the investment behavior and cooperation value of their neighbors,and cooperators invest equally in each neighbor.In real life,heterogeneous investment is often accompanied by time or economic costs.The discreet investors in this paper pay a certain price to obtain their neighbors'investment behavior and cooperation value,which quantifies the time and economic costs of the heterogeneous investment process.The results of Monte Carlo simulation experiments in this study show that discreet investors can effectively resist the invasion of the defectors,form a stable cooperative group and expand the cooperative advantage in evolution.However,when discreet investors pay too high a price,they lose their strategic advantage.The results in this paper help us understand the role of heterogeneous investment in promoting and maintaining human social cooperation. 展开更多
关键词 public goods game heterogeneous investment discreet investors COOPERATION
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Roles of N-cadherin in cerebral cortical development:cooperation with membrane trafficking and actin cytoskeletal regulation
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作者 Shiho Ito Takeshi Kawauchi 《Neural Regeneration Research》 SCIE CAS 2025年第1期188-190,共3页
Cell adhesion plays pivotal roles in the morphogenesis of multicellular organisms.Epithelial cells form several types of cell-to-cell adhesion,including zonula occludens(tight junctions),zonula adhaerens(adherens junc... Cell adhesion plays pivotal roles in the morphogenesis of multicellular organisms.Epithelial cells form several types of cell-to-cell adhesion,including zonula occludens(tight junctions),zonula adhaerens(adherens junctions),and macula adhaerens(desmosomes).Although these adhesion complexes are basically observed only in epithelial cells,cadherins,which are the major cell adhesion molecules of adherens junctions,are expressed in both epithelial and non-epithelial tissues,including neural tissues(Kawauchi,2012).The cadherin superfamily consists of more than 100 members,but classic cadherins. 展开更多
关键词 CEREBRAL SKELETAL COOPERATION
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Cooperative Rate Splitting Transmit Design for Full-Duplex-Enabled Multiple Multicast Communication Systems
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作者 Siyi Duan Mingsheng Wei +2 位作者 Shidang Li Weiqiang Tan Bencheng Yu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第1期619-638,共20页
This paper examines the performance of Full-Duplex Cooperative Rate Splitting(FD-CRS)with Simultaneous Wireless Information and Power Transfer(SWIPT)support in Multiple Input Single Output(MISO)networks.In a Rate Spli... This paper examines the performance of Full-Duplex Cooperative Rate Splitting(FD-CRS)with Simultaneous Wireless Information and Power Transfer(SWIPT)support in Multiple Input Single Output(MISO)networks.In a Rate Splitting Multiple Access(RSMA)multicast system with two local users and one remote user,the common data stream contains the needs of all users,and all users can decode the common data stream.Therefore,each user can receive some information that other users need,and local users with better channel conditions can use this information to further enhance the reception reliability and data rate of users with poor channel quality.Even using Cell-Center-Users(CCUs)as a cooperative relay to assist the transmission of common data can improve the average system speed.To maximize the minimum achievable rate,we optimize the beamforming vector of Base Station(BS),the common streamsplitting vector,the cooperative distributed beamvector and the strong user transmission power under the power budget constraints of BS and relay devices and the service quality requirements constraints of users.Since the whole problem is not convex,we cannot solve it directly.Therefore,we propose a low complexity algorithm based on Successive Convex Approximation(SCA)technology to find the optimal solution to the problemunder consideration.The simulation results show that FD C-RSMA has better gain andmore powerful than FD C-NOMA,HD C-RSMA,RSMA and NOMA. 展开更多
关键词 Full-duplex cooperative rate segmentation SWIPT RSMA power control
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Optimization of Cooperative RelayingMolecular Communications for Nanomedical Applications
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作者 Eman S.Attia Ashraf A.M.Khalaf +4 位作者 Fathi E.Abd El-Samie Saied M.Abd El-atty Konstantinos A.Lizos Osama Alfarraj Heba M.El-Hoseny 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第2期1259-1275,共17页
Recently,nano-systems based on molecular communications via diffusion(MCvD)have been implemented in a variety of nanomedical applications,most notably in targeted drug delivery system(TDDS)scenarios.Furthermore,becaus... Recently,nano-systems based on molecular communications via diffusion(MCvD)have been implemented in a variety of nanomedical applications,most notably in targeted drug delivery system(TDDS)scenarios.Furthermore,because the MCvD is unreliable and there exists molecular noise and inter symbol interference(ISI),cooperative nano-relays can acquire the reliability for drug delivery to targeted diseased cells,especially if the separation distance between the nano transmitter and nano receiver is increased.In this work,we propose an approach for optimizing the performance of the nano system using cooperative molecular communications with a nano relay scheme,while accounting for blood flow effects in terms of drift velocity.The fractions of the molecular drug that should be allocated to the nano transmitter and nano relay positioning are computed using a collaborative optimization problem solved by theModified Central Force Optimization(MCFO)algorithm.Unlike the previous work,the probability of bit error is expressed in a closed-form expression.It is used as an objective function to determine the optimal velocity of the drug molecules and the detection threshold at the nano receiver.The simulation results show that the probability of bit error can be dramatically reduced by optimizing the drift velocity,detection threshold,location of the nano-relay in the proposed nano system,and molecular drug budget. 展开更多
关键词 Nanomedical system molecular communication cooperative relay OPTIMIZATION
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User Preference Aware Hierarchical Edge-User Cooperative Caching Strategy
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作者 Wu Dapeng Yang Lin +2 位作者 Cui Yaping He Peng Wang Ruyan 《China Communications》 SCIE CSCD 2024年第6期69-86,共18页
The emergence of various new services has posed a huge challenge to the existing network architecture.To improve the network delay and backhaul pressure,caching popular contents at the edge of network has been conside... The emergence of various new services has posed a huge challenge to the existing network architecture.To improve the network delay and backhaul pressure,caching popular contents at the edge of network has been considered as a feasible scheme.However,how to efficiently utilize the limited caching resources to cache diverse contents has been confirmed as a tough problem in the past decade.In this paper,considering the time-varying user requests and the heterogeneous content sizes,a user preference aware hierarchical cooperative caching strategy in edge-user caching architecture is proposed.We divide the caching strategy into three phases,that is,the content placement,the content delivery and the content update.In the content placement phase,a cooperative content placement algorithm for local content popularity is designed to cache contents proactively.In the content delivery phase,a cooperative delivery algorithm is proposed to deliver the cached contents.In the content update phase,a content update algorithm is proposed according to the popularity of the contents.Finally,the proposed caching strategy is validated using the MovieLens dataset,and the results reveal that the proposed strategy improves the delay performance by at least 35.3%compared with the other three benchmark strategies. 展开更多
关键词 cooperative caching network delay timevarying popularity user preference
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等离子体环境中相对论效应对类氢离子光电离过程的影响
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作者 戈迪 赵国鹏 +3 位作者 祁月盈 陈晨 高俊文 侯红生 《物理学报》 SCIE EI CAS CSCD 北大核心 2024年第8期97-104,共8页
本文在偶极近似下计算了Debye等离子体环境中C^(5+),Al^(12+)和W^(73+)离子的光电离截面,重点研究了相对论效应对势形共振、Cooper极小和虚态效应的影响.研究结果表明,相对论效应随核电荷数的增大而增大,使得精细结构劈裂越来越显著,在... 本文在偶极近似下计算了Debye等离子体环境中C^(5+),Al^(12+)和W^(73+)离子的光电离截面,重点研究了相对论效应对势形共振、Cooper极小和虚态效应的影响.研究结果表明,相对论效应随核电荷数的增大而增大,使得精细结构劈裂越来越显著,在光电离截面中出现了双共振结构的现象,并且共振峰的大小、宽度和位置的差异都随着核电荷数的增加而越来越大;分截面出现Cooper极小位置的差异也越来越大,在总截面中叠加的极小值越来越浅;出现虚态效应的等离子体屏蔽长度以及低能区光电离截面虚态增强的截面值也存在明显差异. 展开更多
关键词 光电离 相对论效应 势形共振 Cooper极小
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Layered Coded Cache Placement and Cooperative Delivery with Sharing Links in Satellite-Terrestrial Integrated Networks
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作者 Gu Shushi Chen Zihan +2 位作者 Wu Yaonan Zhang Qinyu Wang Ye 《China Communications》 SCIE CSCD 2024年第3期217-229,共13页
Cooperative utilization of multidimensional resources including cache, power and spectrum in satellite-terrestrial integrated networks(STINs) can provide a feasible approach for massive streaming media content deliver... Cooperative utilization of multidimensional resources including cache, power and spectrum in satellite-terrestrial integrated networks(STINs) can provide a feasible approach for massive streaming media content delivery over the seamless global coverage area. However, the on-board supportable resources of a single satellite are extremely limited and lack of interaction with others. In this paper, we design a network model with two-layered cache deployment, i.e., satellite layer and ground base station layer, and two types of sharing links, i.e., terrestrial-satellite sharing(TSS) links and inter-satellite sharing(ISS) links, to enhance the capability of cooperative delivery over STINs. Thus, we use rateless codes for the content divided-packet transmission, and derive the total energy efficiency(EE) in the whole transmission procedure, which is defined as the ratio of traffic offloading and energy consumption. We formulate two optimization problems about maximizing EE in different sharing scenarios(only TSS and TSS-ISS),and propose two optimized algorithms to obtain the optimal content placement matrixes, respectively.Simulation results demonstrate that, enabling sharing links with optimized cache placement have more than 2 times improvement of EE performance than other traditional placement schemes. Particularly, TSS-ISS schemes have the higher EE performance than only TSS schemes under the conditions of enough number of satellites and smaller inter-satellite distances. 展开更多
关键词 coded content placement cooperative delivery energy efficiency sharing links STINs
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Joint computation offloading and parallel scheduling to maximize delay-guarantee in cooperative MEC systems
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作者 Mian Guo Mithun Mukherjee +3 位作者 Jaime Lloret Lei Li Quansheng Guan Fei Ji 《Digital Communications and Networks》 SCIE CSCD 2024年第3期693-705,共13页
The growing development of the Internet of Things(IoT)is accelerating the emergence and growth of new IoT services and applications,which will result in massive amounts of data being generated,transmitted and pro-cess... The growing development of the Internet of Things(IoT)is accelerating the emergence and growth of new IoT services and applications,which will result in massive amounts of data being generated,transmitted and pro-cessed in wireless communication networks.Mobile Edge Computing(MEC)is a desired paradigm to timely process the data from IoT for value maximization.In MEC,a number of computing-capable devices are deployed at the network edge near data sources to support edge computing,such that the long network transmission delay in cloud computing paradigm could be avoided.Since an edge device might not always have sufficient resources to process the massive amount of data,computation offloading is significantly important considering the coop-eration among edge devices.However,the dynamic traffic characteristics and heterogeneous computing capa-bilities of edge devices challenge the offloading.In addition,different scheduling schemes might provide different computation delays to the offloaded tasks.Thus,offloading in mobile nodes and scheduling in the MEC server are coupled to determine service delay.This paper seeks to guarantee low delay for computation intensive applica-tions by jointly optimizing the offloading and scheduling in such an MEC system.We propose a Delay-Greedy Computation Offloading(DGCO)algorithm to make offloading decisions for new tasks in distributed computing-enabled mobile devices.A Reinforcement Learning-based Parallel Scheduling(RLPS)algorithm is further designed to schedule offloaded tasks in the multi-core MEC server.With an offloading delay broadcast mechanism,the DGCO and RLPS cooperate to achieve the goal of delay-guarantee-ratio maximization.Finally,the simulation results show that our proposal can bound the end-to-end delay of various tasks.Even under slightly heavy task load,the delay-guarantee-ratio given by DGCO-RLPS can still approximate 95%,while that given by benchmarked algorithms is reduced to intolerable value.The simulation results are demonstrated the effective-ness of DGCO-RLPS for delay guarantee in MEC. 展开更多
关键词 Edge computing Computation offloading Parallel scheduling Mobile-edge cooperation Delay guarantee
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