After a composite service is deployed, user privacy requirements and trust levels of component services are subject to variation. When the changes occur, it is critical to preserve privacy information flow security. W...After a composite service is deployed, user privacy requirements and trust levels of component services are subject to variation. When the changes occur, it is critical to preserve privacy information flow security. We propose an approach to preserve privacy information flow security in composite service evolution. First, a privacy data item dependency analysis method based on a Petri net model is presented. Then the set of privacy data items collected by each component service is derived through a privacy data item dependency graph, and the security scope of each component service is calculated. Finally, the evolution operations that preserve privacy information flow security are defined. By applying these evolution operations, the re-verification process is avoided and the evolution efficiency is improved. To illustrate the effectiveness of our approach, a case study is presented. The experimental results indicate that our approach has high evolution efficiency and can greatly reduce the cost of evolution compared with re-verifying the entire composite service.展开更多
Since the official operation of the BeiDou Global Navigation Satellite System (BDS-3), it has played a vitalrole in the national economy, national defence and security, and to enhance the people’s productivity and li...Since the official operation of the BeiDou Global Navigation Satellite System (BDS-3), it has played a vitalrole in the national economy, national defence and security, and to enhance the people’s productivity and life. Basedupon the three main characteristics, route design inheritance and development, highly integrated services, and “spiraling”incremental development, this paper introduces the service composition of BeiDou Navigation Satellite System (BDS)and summarizes the evolution of four types of BDS services, that include Positioning, Navigation and Timing (PNT),message communications, navigation augmentation, and international Search and Rescue (SAR). Moreover, the designfeatures and performance of each service are discussed in detail, and the development trend of BDS services is examinedin the light of the latest round of changes in the Global Navigation Satellite System (GNSS). Finally, developmentproposals are proposed, namely, stable operation of the system, enhancement of service performance, and empowermentthrough integration of multiple means.展开更多
With the development of message service in telecom networks as well as the Internet,multiple message service formats have been emerging,including Short Message Service (SMS),Multimedia Messaging Service (MMS),Mobile E...With the development of message service in telecom networks as well as the Internet,multiple message service formats have been emerging,including Short Message Service (SMS),Multimedia Messaging Service (MMS),Mobile Email Message (MEM) and Instant Message (IM).Based on the latest research achievements of OMA CPM Organization and GSMA RCS Organization,the message service evolution may have two phases:Integration and convergence,with corresponding overall framework realization methods.展开更多
The issue of burst losses imposes a constraint on the development of Optical Burst Switching （OBS） networks. Heavy burst losses strongly affect the Quality of Service （QoS） intended by end users. This article pres...The issue of burst losses imposes a constraint on the development of Optical Burst Switching （OBS） networks. Heavy burst losses strongly affect the Quality of Service （QoS） intended by end users. This article presents a QoS aware Routing and Wavelength Allocation （RWA） technique for burst switching in OBS networks. The RWA problem is modeled as a bi-objective Integer Linear Programming （ILP） problem, where objective functions are based on minimizing the number of wavelengths used and the number of hops traversed to fulfill the burst transmission requests for a given set of node pairs. The ILP model is solved using a novel approach based on a Differential Evolution （DE） algorithm. Analytical results show that the DE algorithm provides a better performance compared to shortest path routing, which is a widely accepted routing strategy for OBS networks.展开更多
A comprehensive understanding of the spatial-temporal evolution and driving forces on ecosystem services(ES)is essential for the agro-pastoral ecotone’s ecological security in northern China.However,the land-use patt...A comprehensive understanding of the spatial-temporal evolution and driving forces on ecosystem services(ES)is essential for the agro-pastoral ecotone’s ecological security in northern China.However,the land-use pattern(LULC)agglomeration with spatial differentiation in the pastoral and agricultural areas has been rarely concerned.Taking distinct LULC(1980-2018)in Chifeng as an example,we compared four crucial categories of ESs with InVEST.Using SEM,we further contrasted the effects of several variables on regional ES variations in pastoral-dominated(North)and agriculture-dominated(South)regions,respectively.Results revealed the conversion between forest and grassland oriented the LULC transformation in the North.In contrast,human-activitiy-oriented land tended to occupy environmentally sensitive places in the South.Similar ES variations were supplied with the North outperforming the South when soil conservation was omitted.As for the impacts of regional ES variations,the natural and LULC policies both showed positive effects,whereas the anthropogenic factors showed positive in the North,which was negative in the South.Therefore,the ecologicallymaintained-dominant and ecologically-restored-dominant strategies should be separately adopted in the North and South.Our study provided appropriate regional ecological management suggestions for balancing the LULC-driven conflicts between ecological protection and regional development.展开更多
基金Project supported by the National Natural Science Foundation of China(Nos.61562087 and 61772270)the National High-Tech R&D Program(863)of China(No.2015AA015303)+2 种基金the Natural Science Foundation of Jiangsu Province,China(No.BK20130735)the Universities Natural Science Foundation of Jiangsu Province,China(No.13KJB520011)the Science Foundation of Nanjing Institute of Technology,China(No.YKJ201420)
文摘After a composite service is deployed, user privacy requirements and trust levels of component services are subject to variation. When the changes occur, it is critical to preserve privacy information flow security. We propose an approach to preserve privacy information flow security in composite service evolution. First, a privacy data item dependency analysis method based on a Petri net model is presented. Then the set of privacy data items collected by each component service is derived through a privacy data item dependency graph, and the security scope of each component service is calculated. Finally, the evolution operations that preserve privacy information flow security are defined. By applying these evolution operations, the re-verification process is avoided and the evolution efficiency is improved. To illustrate the effectiveness of our approach, a case study is presented. The experimental results indicate that our approach has high evolution efficiency and can greatly reduce the cost of evolution compared with re-verifying the entire composite service.
文摘Since the official operation of the BeiDou Global Navigation Satellite System (BDS-3), it has played a vitalrole in the national economy, national defence and security, and to enhance the people’s productivity and life. Basedupon the three main characteristics, route design inheritance and development, highly integrated services, and “spiraling”incremental development, this paper introduces the service composition of BeiDou Navigation Satellite System (BDS)and summarizes the evolution of four types of BDS services, that include Positioning, Navigation and Timing (PNT),message communications, navigation augmentation, and international Search and Rescue (SAR). Moreover, the designfeatures and performance of each service are discussed in detail, and the development trend of BDS services is examinedin the light of the latest round of changes in the Global Navigation Satellite System (GNSS). Finally, developmentproposals are proposed, namely, stable operation of the system, enhancement of service performance, and empowermentthrough integration of multiple means.
文摘With the development of message service in telecom networks as well as the Internet,multiple message service formats have been emerging,including Short Message Service (SMS),Multimedia Messaging Service (MMS),Mobile Email Message (MEM) and Instant Message (IM).Based on the latest research achievements of OMA CPM Organization and GSMA RCS Organization,the message service evolution may have two phases:Integration and convergence,with corresponding overall framework realization methods.
文摘The issue of burst losses imposes a constraint on the development of Optical Burst Switching （OBS） networks. Heavy burst losses strongly affect the Quality of Service （QoS） intended by end users. This article presents a QoS aware Routing and Wavelength Allocation （RWA） technique for burst switching in OBS networks. The RWA problem is modeled as a bi-objective Integer Linear Programming （ILP） problem, where objective functions are based on minimizing the number of wavelengths used and the number of hops traversed to fulfill the burst transmission requests for a given set of node pairs. The ILP model is solved using a novel approach based on a Differential Evolution （DE） algorithm. Analytical results show that the DE algorithm provides a better performance compared to shortest path routing, which is a widely accepted routing strategy for OBS networks.
基金This study was funded by The National Key Research and Development Program of China(No.2016YFC0503603)The Science and Technology Plan Project of Inner Mongolia(No.2022YFDZ0073)。
文摘A comprehensive understanding of the spatial-temporal evolution and driving forces on ecosystem services(ES)is essential for the agro-pastoral ecotone’s ecological security in northern China.However,the land-use pattern(LULC)agglomeration with spatial differentiation in the pastoral and agricultural areas has been rarely concerned.Taking distinct LULC(1980-2018)in Chifeng as an example,we compared four crucial categories of ESs with InVEST.Using SEM,we further contrasted the effects of several variables on regional ES variations in pastoral-dominated(North)and agriculture-dominated(South)regions,respectively.Results revealed the conversion between forest and grassland oriented the LULC transformation in the North.In contrast,human-activitiy-oriented land tended to occupy environmentally sensitive places in the South.Similar ES variations were supplied with the North outperforming the South when soil conservation was omitted.As for the impacts of regional ES variations,the natural and LULC policies both showed positive effects,whereas the anthropogenic factors showed positive in the North,which was negative in the South.Therefore,the ecologicallymaintained-dominant and ecologically-restored-dominant strategies should be separately adopted in the North and South.Our study provided appropriate regional ecological management suggestions for balancing the LULC-driven conflicts between ecological protection and regional development.
