Elastic control could balance the distributed control plane in Software-Defined Networking(SDN). Dynamic switch migration has been proposed to achieve it. However, existing schemes mainly focus on how to execute migra...Elastic control could balance the distributed control plane in Software-Defined Networking(SDN). Dynamic switch migration has been proposed to achieve it. However, existing schemes mainly focus on how to execute migration operation, but not why. This paper designs a decision-making mechanism based on zero-sum game theory to reelect a new controller as the master for migrated switches. It first chooses a switch for migration in the heavy controller which invites its neighbors as the game players to compete for the master role of this switch in the game-playing field(GPF) which is an occasional and loose domain for game-playing. Second, based on the concept of GPF, we design a decentralized strategy to play the game and determine which player as the final master. We implement it by extending the Open Flow protocol. Finally, numerical results demonstrate that our distributed strategy can approach elastic control plane with better performance.展开更多
As the ability of a single agent is limited while information and resources in multi-agent systems are distributed, cooperation is necessary for agents to accomplish a complex task. In the open and changeable environm...As the ability of a single agent is limited while information and resources in multi-agent systems are distributed, cooperation is necessary for agents to accomplish a complex task. In the open and changeable environment on the Internet, it is of great significance to research a system flexible and capable in dynamic evolution that can find a collaboration method for agents which can be used in dynamic evolution process. With such a method, agents accomplish tasks for an overall target and at the same time, the collaborative relationship of agents can be adjusted with the change of environment. A method of task decomposition and collaboration of agents by improved contract net protocol is introduced. Finally, analysis on the result of the experiments is performed to verify the improved contract net protocol can greatly increase the efficiency of communication and collaboration in multi-agent system.展开更多
Objective:To explore the mechanism of acupuncture in regulating cognitive deficits in insomnia rats by observing the effect of acupuncture on microglia in thalamic reticular nucleus(TRN).Methods:Thirty rats were rando...Objective:To explore the mechanism of acupuncture in regulating cognitive deficits in insomnia rats by observing the effect of acupuncture on microglia in thalamic reticular nucleus(TRN).Methods:Thirty rats were randomly divided into a control group,a model group and an acupuncture group,with 10 rats in each group.The insomnia model was established by intraperitoneal injection of para-chlorophenylalanine(PCPA)once a day for 2 d.Rats in the control group were intraperitoneally injected with the same amount of normal saline.Rats in the acupuncture group received acupuncture at Neiguan(PC 6)and Zusanli(ST 36)for 5 consecutive days.The CLOCKLAB 2 data acquisition system was used to dynamically observe the sleep of the rats throughout the experiment.The cognition of rats was evaluated by event-related potentials(ERPs).After intervention,brain tissue was extracted.Immunofluorescence was used to test the fluorescence expression in TRN region.The concentrations of interleukin(IL)-1βand tumor necrosis factor(TNF)-αwere detected by enzyme-linked immunosorbent assay.Results:After intraperitoneal injection of PCPA suspension,the spontaneous activity in light period of rats in the model group and acupuncture group increased significantly compared with the control group(both P<0.01).After acupuncture treatment,the rats in the acupuncture group had much less spontaneous activity during the light period than those in the model group(P<0.01),and the results indicated that acupuncture could effectively improve the sleep quality of insomnia rats.Compared with the control group,rats in the model group showed that the P3 latency,the average optical density of microglia,and the concentrations of IL-1βand TNF-αincreased significantly(all P<0.05),and the P3 amplitude decreased significantly(P<0.01).Compared with the model group,rats in the acupuncture group presented that the P3 latency,the average optical density of microglia,and the concentrations of IL-1βand TNF-αwere significantly decreased(all P<0.05),and the amplitude of P3 was significantly increased(P<0.05).Conclusion:Acupuncture possesses an ability to improve the cognitive state in insomnia rats.The mechanism may be related to inhibiting the microglial activation,diminishing the levels of pro-inflammatory mediators like IL-1βand TNF-α,and promoting the recovery of central nervous system function.展开更多
This paper focuses on the existence, uniqueness and global robust stability of equilibrium point for complex-valued recurrent neural networks with multiple time-delays and under parameter uncertainties with respect to...This paper focuses on the existence, uniqueness and global robust stability of equilibrium point for complex-valued recurrent neural networks with multiple time-delays and under parameter uncertainties with respect to two activation functions. Two sufficient conditions for robust stability of the considered neural networks are presented and established in two new time-independent relationships between the network parameters of the neural system, Finally, three illustrative examples are given to demonstrate the theoretical results.展开更多
Software Defined Networking (SDN) is an emerging networking paradigm that assumes a logically centralized control plane separated from the data plane. Despite all its advantages, separating the control and data plan...Software Defined Networking (SDN) is an emerging networking paradigm that assumes a logically centralized control plane separated from the data plane. Despite all its advantages, separating the control and data planes introduces new challenges regarding resilient communications between the two. That is, disconnec- tions between switches and their controllers could result in substantial packet loss and performance degradation. This paper addresses this challenge by studying the issue of control traffic protection in SDNs with arbitrary numbers of controllers. Specifically, we propose a control traffic protection scheme that combines both local rerouting and constrained reverse path forwarding protections, through which switches can locally react to fail- ures and redirect the control traffic using standby backup forwarding options. Our goal is then to find a set of primary routes for control traffic, called protected control network, where as many switches as possible can benefit from the proposed protection scheme. We formulate the protected control network problem, prove its NP-hardness, and develop an algorithm that reconciles proteetability and performance (e.g., switch-to-control latency). Through extensive simulations based on real topologies, we show that our approach significantly im- proves protectability of control traffic. The results should help further the process of deploying SDN in real-world networks.展开更多
基金supported by the Foundation for Innovative Research Groups of the National Natural Science Foundation of China(Grant No.61521003)the National Basic Research Program of China(2012CB315901,2013CB329104)+2 种基金the National Natural Science Foundation of China(Grant No.61372121,61309020,61309019)the National High-Tech Research&Development Program of China(Grant No.2013AA013505)the National Science and Technology Support Program Project(Grant No.2014BAH30B01)
文摘Elastic control could balance the distributed control plane in Software-Defined Networking(SDN). Dynamic switch migration has been proposed to achieve it. However, existing schemes mainly focus on how to execute migration operation, but not why. This paper designs a decision-making mechanism based on zero-sum game theory to reelect a new controller as the master for migrated switches. It first chooses a switch for migration in the heavy controller which invites its neighbors as the game players to compete for the master role of this switch in the game-playing field(GPF) which is an occasional and loose domain for game-playing. Second, based on the concept of GPF, we design a decentralized strategy to play the game and determine which player as the final master. We implement it by extending the Open Flow protocol. Finally, numerical results demonstrate that our distributed strategy can approach elastic control plane with better performance.
基金Projects(61173026,61373045,61202039)supported by the National Natural Science Foundation of ChinaProjects(K5051223008,BDY221411)supported by the Fundamental Research Funds for the Central Universities of ChinaProject(2012AA02A603)supported by the High-Tech Research and Development Program of China
文摘As the ability of a single agent is limited while information and resources in multi-agent systems are distributed, cooperation is necessary for agents to accomplish a complex task. In the open and changeable environment on the Internet, it is of great significance to research a system flexible and capable in dynamic evolution that can find a collaboration method for agents which can be used in dynamic evolution process. With such a method, agents accomplish tasks for an overall target and at the same time, the collaborative relationship of agents can be adjusted with the change of environment. A method of task decomposition and collaboration of agents by improved contract net protocol is introduced. Finally, analysis on the result of the experiments is performed to verify the improved contract net protocol can greatly increase the efficiency of communication and collaboration in multi-agent system.
文摘Objective:To explore the mechanism of acupuncture in regulating cognitive deficits in insomnia rats by observing the effect of acupuncture on microglia in thalamic reticular nucleus(TRN).Methods:Thirty rats were randomly divided into a control group,a model group and an acupuncture group,with 10 rats in each group.The insomnia model was established by intraperitoneal injection of para-chlorophenylalanine(PCPA)once a day for 2 d.Rats in the control group were intraperitoneally injected with the same amount of normal saline.Rats in the acupuncture group received acupuncture at Neiguan(PC 6)and Zusanli(ST 36)for 5 consecutive days.The CLOCKLAB 2 data acquisition system was used to dynamically observe the sleep of the rats throughout the experiment.The cognition of rats was evaluated by event-related potentials(ERPs).After intervention,brain tissue was extracted.Immunofluorescence was used to test the fluorescence expression in TRN region.The concentrations of interleukin(IL)-1βand tumor necrosis factor(TNF)-αwere detected by enzyme-linked immunosorbent assay.Results:After intraperitoneal injection of PCPA suspension,the spontaneous activity in light period of rats in the model group and acupuncture group increased significantly compared with the control group(both P<0.01).After acupuncture treatment,the rats in the acupuncture group had much less spontaneous activity during the light period than those in the model group(P<0.01),and the results indicated that acupuncture could effectively improve the sleep quality of insomnia rats.Compared with the control group,rats in the model group showed that the P3 latency,the average optical density of microglia,and the concentrations of IL-1βand TNF-αincreased significantly(all P<0.05),and the P3 amplitude decreased significantly(P<0.01).Compared with the model group,rats in the acupuncture group presented that the P3 latency,the average optical density of microglia,and the concentrations of IL-1βand TNF-αwere significantly decreased(all P<0.05),and the amplitude of P3 was significantly increased(P<0.05).Conclusion:Acupuncture possesses an ability to improve the cognitive state in insomnia rats.The mechanism may be related to inhibiting the microglial activation,diminishing the levels of pro-inflammatory mediators like IL-1βand TNF-α,and promoting the recovery of central nervous system function.
基金This publication was made possible by NPRP Grant ≠NPRP 4-1162-1-181 from the Qatar National Research Fund (a member of Qatar Foundation). The statements made herein are solely the responsibility of the authors. This work was also supported by Natural Science Foundation of China (Grant No. 61374078).
文摘This paper focuses on the existence, uniqueness and global robust stability of equilibrium point for complex-valued recurrent neural networks with multiple time-delays and under parameter uncertainties with respect to two activation functions. Two sufficient conditions for robust stability of the considered neural networks are presented and established in two new time-independent relationships between the network parameters of the neural system, Finally, three illustrative examples are given to demonstrate the theoretical results.
基金supported in part by National High-tech R&D Program of China(863 Program)(Grant Nos.2013AA0133012015AA016101)
文摘Software Defined Networking (SDN) is an emerging networking paradigm that assumes a logically centralized control plane separated from the data plane. Despite all its advantages, separating the control and data planes introduces new challenges regarding resilient communications between the two. That is, disconnec- tions between switches and their controllers could result in substantial packet loss and performance degradation. This paper addresses this challenge by studying the issue of control traffic protection in SDNs with arbitrary numbers of controllers. Specifically, we propose a control traffic protection scheme that combines both local rerouting and constrained reverse path forwarding protections, through which switches can locally react to fail- ures and redirect the control traffic using standby backup forwarding options. Our goal is then to find a set of primary routes for control traffic, called protected control network, where as many switches as possible can benefit from the proposed protection scheme. We formulate the protected control network problem, prove its NP-hardness, and develop an algorithm that reconciles proteetability and performance (e.g., switch-to-control latency). Through extensive simulations based on real topologies, we show that our approach significantly im- proves protectability of control traffic. The results should help further the process of deploying SDN in real-world networks.