In order to carry out comprehensive decision-making of multi-class shared parking measures within a region, a bilevel model assisting decision-making is proposed. The upper level selects parkers' average satisfaction...In order to carry out comprehensive decision-making of multi-class shared parking measures within a region, a bilevel model assisting decision-making is proposed. The upper level selects parkers' average satisfaction and the violation rate during peak hours as indices in object function, and sets probability distribution models describing dynamic parking demand of each site, the feasibility of shared parking scenarios and occupancy requirements during peak hours of each parking lot as restrictions. The simulation model in the lower level sets up rules to assign each parker in the random parking demand series to the proper parking lot. An iterative method is proposed to confirm the state of each parking lot at the start of formal simulations. Besides, two patterns linking initialization and formal simulation are presented to acquire multiple solutions. The results of the numerical examples indicate the effectiveness of the model and solution methods.展开更多
The Cloud is increasingly being used to store and process big data for its tenants and classical security mechanisms using encryption are neither sufficiently efficient nor suited to the task of protecting big data in...The Cloud is increasingly being used to store and process big data for its tenants and classical security mechanisms using encryption are neither sufficiently efficient nor suited to the task of protecting big data in the Cloud.In this paper,we present an alternative approach which divides big data into sequenced parts and stores them among multiple Cloud storage service providers.Instead of protecting the big data itself,the proposed scheme protects the mapping of the various data elements to each provider using a trapdoor function.Analysis,comparison and simulation prove that the proposed scheme is efficient and secure for the big data of Cloud tenants.展开更多
In Elastic Optical Networks(EONs)with flexible bandwidth allocation,the blocking probability is high because of spectral contention.Similar to the functionality of wavelength conversion in Wavelength-Division-Multiple...In Elastic Optical Networks(EONs)with flexible bandwidth allocation,the blocking probability is high because of spectral contention.Similar to the functionality of wavelength conversion in Wavelength-Division-Multiplexing(WDM)networks,waveband conversion has been proposed to solve spectral contention in EONs.In this paper,we discuss the design of node architectures for an EON with waveband conversion.Four node architectures with shared Tuneable Waveband Converters(TWBCs)are proposed,and their blocking performances are evaluated by simulation.Simulation results show that the blocking probability of a node is significantly improved by waveband conversion.The sharing efficiency of waveband converters is also investigated.Simulation results show that at the same blocking rate,the node architecture with converters shared per node can save more than 20% waveband converters compared with that of the one with converters shared per link.展开更多
基金The Planning Program of Science and Technology of Ministry of Housing and Urban-Rural Development of China (No. 2010-K5-16)
文摘In order to carry out comprehensive decision-making of multi-class shared parking measures within a region, a bilevel model assisting decision-making is proposed. The upper level selects parkers' average satisfaction and the violation rate during peak hours as indices in object function, and sets probability distribution models describing dynamic parking demand of each site, the feasibility of shared parking scenarios and occupancy requirements during peak hours of each parking lot as restrictions. The simulation model in the lower level sets up rules to assign each parker in the random parking demand series to the proper parking lot. An iterative method is proposed to confirm the state of each parking lot at the start of formal simulations. Besides, two patterns linking initialization and formal simulation are presented to acquire multiple solutions. The results of the numerical examples indicate the effectiveness of the model and solution methods.
基金supported in part by the National Nature Science Foundation of China under Grant No.61402413 and 61340058 the "Six Kinds Peak Talents Plan" project of Jiangsu Province under Grant No.ll-JY-009+2 种基金the Nature Science Foundation of Zhejiang Province under Grant No.LY14F020019, Z14F020006 and Y1101183the China Postdoctoral Science Foundation funded project under Grant No.2012M511732Jiangsu Province Postdoctoral Science Foundation funded project Grant No.1102014C
文摘The Cloud is increasingly being used to store and process big data for its tenants and classical security mechanisms using encryption are neither sufficiently efficient nor suited to the task of protecting big data in the Cloud.In this paper,we present an alternative approach which divides big data into sequenced parts and stores them among multiple Cloud storage service providers.Instead of protecting the big data itself,the proposed scheme protects the mapping of the various data elements to each provider using a trapdoor function.Analysis,comparison and simulation prove that the proposed scheme is efficient and secure for the big data of Cloud tenants.
基金supported by the National Key Basic Research Program of China (973 Program) under Grants No. 2010CB328201,No.2010CB328202the National Natural Science Foundation of China under Grants No. 60907030,No. 61275071,No. 60736003,No. 60931160439the National High Technical Research and Development Program of China (863 Program)under Grant No. 2011AA01A106
文摘In Elastic Optical Networks(EONs)with flexible bandwidth allocation,the blocking probability is high because of spectral contention.Similar to the functionality of wavelength conversion in Wavelength-Division-Multiplexing(WDM)networks,waveband conversion has been proposed to solve spectral contention in EONs.In this paper,we discuss the design of node architectures for an EON with waveband conversion.Four node architectures with shared Tuneable Waveband Converters(TWBCs)are proposed,and their blocking performances are evaluated by simulation.Simulation results show that the blocking probability of a node is significantly improved by waveband conversion.The sharing efficiency of waveband converters is also investigated.Simulation results show that at the same blocking rate,the node architecture with converters shared per node can save more than 20% waveband converters compared with that of the one with converters shared per link.