Cache-enabled small cell networks have been regarded as a promising approach for network operators to cope with the explosive data traffic growth in future 5 G networks. However, the user association and resource allo...Cache-enabled small cell networks have been regarded as a promising approach for network operators to cope with the explosive data traffic growth in future 5 G networks. However, the user association and resource allocation mechanism has not been thoroughly studied under given content placement situation. In this paper, we formulate the joint optimization problem of user association and resource allocation as a mixed integer nonlinear programming(MINLP) problem aiming at deriving a balance between the total utility of data rates and the total data rates retrieved from caches. To solve this problem, we propose a distributed relaxing-rounding method. Simulation results demonstrate that the distributed relaxing-rounding method outperforms traditional max-SINR method and range-expansion method in terms of both total utility of data rates and total data rates retrieved from caches in practical scenarios. In addition, effects of storage and backhaul capacities on the performance are also studied.展开更多
Climate protection is a problem of sustaining a public resource. All countries of the world should take action to deal with climate change. However, such an action is actually a game process where each country chooses...Climate protection is a problem of sustaining a public resource. All countries of the world should take action to deal with climate change. However, such an action is actually a game process where each country chooses to cooperate or defect under constrained condition. Here we study the group behavior of countries in dealing with climate change. In our study, the countries of the world are considered as players who are distributed on an assumed spatial network. A new evolution rule is proposed to model the game process among the players. Our extensive experiments demonstrate that under constrained condition, the local psychology of players possibly results in the formation of local group. Some local and global oscillations can be found where part or all of the players change their choices periodically.展开更多
Ubiquitous breadth of applications and data to quantify the sea and other features need an efficient means to provide information processing technology ensure. This paper analyzes the ubiquitous network application pl...Ubiquitous breadth of applications and data to quantify the sea and other features need an efficient means to provide information processing technology ensure. This paper analyzes the ubiquitous network application platform and its initial request for all kinds of computing and network resources. The current cloud computing technology distributed processing capabilities, which were assessed. And cloud computing in the future will provide a reference to the proposed application of research on cloud computing technology application and a new application fields.展开更多
The optimization process of embedded, or DG （distributed generation） is a very complex task, and it should be evaluated and compared by means of multi-criteria methods of analysis. The classical method for selection...The optimization process of embedded, or DG （distributed generation） is a very complex task, and it should be evaluated and compared by means of multi-criteria methods of analysis. The classical method for selection is usually based only on a single criterion analysis, and it is defined by thermal or economic aspects. The problem of optimal dispatch of DG is typical example of optimization, because it differs from the classical problem of generation dispatch in the power system, due to the specific criteria related to the DG interconnection. The most important goals are to maximize the renewable production and to minimize the total cost, while satisfying additional constraints related to the operation of a distribution network. As there are many DGs in a distribution network, it is very complicated to decide the optimal DG outputs to satisfy all the criteria and constraints imposed by the distribution network. Another problem is the lack of the dispatcher control over DGs, and very often, the only available action is to switch on or off the generator. Finally, network operator and DG owner perspective are often opposed regarding appropriate control action in the network. In this paper, a multicriteria decision support based on AHP （analytical hierarchical processes） method is proposed for the choice of the dispatching action. The method is illustrated on the choice of the DG to be switched off in the case or reverse power flow.展开更多
基金supported by National Natural Science Foundation of China under Grants No. 61371087 and 61531013The Research Fund of Ministry of Education-China Mobile (MCM20150102)
文摘Cache-enabled small cell networks have been regarded as a promising approach for network operators to cope with the explosive data traffic growth in future 5 G networks. However, the user association and resource allocation mechanism has not been thoroughly studied under given content placement situation. In this paper, we formulate the joint optimization problem of user association and resource allocation as a mixed integer nonlinear programming(MINLP) problem aiming at deriving a balance between the total utility of data rates and the total data rates retrieved from caches. To solve this problem, we propose a distributed relaxing-rounding method. Simulation results demonstrate that the distributed relaxing-rounding method outperforms traditional max-SINR method and range-expansion method in terms of both total utility of data rates and total data rates retrieved from caches in practical scenarios. In addition, effects of storage and backhaul capacities on the performance are also studied.
基金Supported by the State Key Laboratory of Rail Traffic Control and Safety under Grant Nos.RCS2008ZZ001 and RCS2010ZZ001,Beijing Jiaotong University
文摘Climate protection is a problem of sustaining a public resource. All countries of the world should take action to deal with climate change. However, such an action is actually a game process where each country chooses to cooperate or defect under constrained condition. Here we study the group behavior of countries in dealing with climate change. In our study, the countries of the world are considered as players who are distributed on an assumed spatial network. A new evolution rule is proposed to model the game process among the players. Our extensive experiments demonstrate that under constrained condition, the local psychology of players possibly results in the formation of local group. Some local and global oscillations can be found where part or all of the players change their choices periodically.
文摘Ubiquitous breadth of applications and data to quantify the sea and other features need an efficient means to provide information processing technology ensure. This paper analyzes the ubiquitous network application platform and its initial request for all kinds of computing and network resources. The current cloud computing technology distributed processing capabilities, which were assessed. And cloud computing in the future will provide a reference to the proposed application of research on cloud computing technology application and a new application fields.
文摘The optimization process of embedded, or DG （distributed generation） is a very complex task, and it should be evaluated and compared by means of multi-criteria methods of analysis. The classical method for selection is usually based only on a single criterion analysis, and it is defined by thermal or economic aspects. The problem of optimal dispatch of DG is typical example of optimization, because it differs from the classical problem of generation dispatch in the power system, due to the specific criteria related to the DG interconnection. The most important goals are to maximize the renewable production and to minimize the total cost, while satisfying additional constraints related to the operation of a distribution network. As there are many DGs in a distribution network, it is very complicated to decide the optimal DG outputs to satisfy all the criteria and constraints imposed by the distribution network. Another problem is the lack of the dispatcher control over DGs, and very often, the only available action is to switch on or off the generator. Finally, network operator and DG owner perspective are often opposed regarding appropriate control action in the network. In this paper, a multicriteria decision support based on AHP （analytical hierarchical processes） method is proposed for the choice of the dispatching action. The method is illustrated on the choice of the DG to be switched off in the case or reverse power flow.
