With the growing popularity of data-intensive services on the Internet, the traditional process-centric model for business process meets challenges due to the lack of abilities to describe data semantics and dependenc...With the growing popularity of data-intensive services on the Internet, the traditional process-centric model for business process meets challenges due to the lack of abilities to describe data semantics and dependencies, resulting in the inflexibility of the design and implement for the processes. This paper proposes a novel data-aware business process model which is able to describe both explicit control flow and implicit data flow. Data model with dependencies which are formulated by Linear-time Temporal Logic(LTL) is presented, and their satisfiability is validated by an automaton-based model checking algorithm. Data dependencies are fully considered in modeling phase, which helps to improve the efficiency and reliability of programming during developing phase. Finally, a prototype system based on j BPM for data-aware workflow is designed using such model, and has been deployed to Beijing Kingfore heating management system to validate the flexibility, efficacy and convenience of our approach for massive coding and large-scale system management in reality.展开更多
In order to improve the energy efficiency, reduce the CO2 emission and decrease the cost, a cogenera- tion system for desalination water, heat and power production was studied in this paper. The superstructure of the ...In order to improve the energy efficiency, reduce the CO2 emission and decrease the cost, a cogenera- tion system for desalination water, heat and power production was studied in this paper. The superstructure of the cogeneration system consisted of a coal-based thermal power plant （TPP）, a multi-stage flash desalination （MSF） module and reverse osmosis desalination （RO） module. For different demands of water, heat and power production, the corresponding optimal production structure was different. After reasonable simplification, the process model ot each unit was built. The economical model, including the unit investment, and operation and maintenance cost, was presented. By solving this non-linear programming （NLP） model, whose objective is to minimize the annual cost, an optimal cogeneration system can be obtained. Compared to separate production systems, the optimal system can reduce 16.1%-21.7% of the total annual cost. showing this design method was effective.展开更多
The specification of authorization policies in access control models proposed so far cannot satisfy the requirements in workflow management systems(WFMSs).Furthermore,existing approaches have not provided effective co...The specification of authorization policies in access control models proposed so far cannot satisfy the requirements in workflow management systems(WFMSs).Furthermore,existing approaches have not provided effective conflict detection and resolution methods to maintain the consistency of authorization polices in WFMSs.To address these concerns,we propose the definition of authorization policies in which context constraints are considered and the complicated requirements in WFMSs can be satisfied.Based on the definition,we put forward static and dynamic conflict detection methods for authorization policies.By defining two new concepts,the precedence establishment rule and the conflict resolution policy,we provide a flexible approach to resolving conflicts.展开更多
The authors study radial solutions to a model equation for the Navier-Stokes equations. It is shown that the model equation has self-similar singular solution if 5 ≤ n ≤ 9. It is also shown that the solution will bl...The authors study radial solutions to a model equation for the Navier-Stokes equations. It is shown that the model equation has self-similar singular solution if 5 ≤ n ≤ 9. It is also shown that the solution will blow up if the initial data is radial, large enough and n ≥ 5.展开更多
基金supported by the National Natural Science Foundation of China (No. 61502043, No. 61132001)Beijing Natural Science Foundation (No. 4162042)BeiJing Talents Fund (No. 2015000020124G082)
文摘With the growing popularity of data-intensive services on the Internet, the traditional process-centric model for business process meets challenges due to the lack of abilities to describe data semantics and dependencies, resulting in the inflexibility of the design and implement for the processes. This paper proposes a novel data-aware business process model which is able to describe both explicit control flow and implicit data flow. Data model with dependencies which are formulated by Linear-time Temporal Logic(LTL) is presented, and their satisfiability is validated by an automaton-based model checking algorithm. Data dependencies are fully considered in modeling phase, which helps to improve the efficiency and reliability of programming during developing phase. Finally, a prototype system based on j BPM for data-aware workflow is designed using such model, and has been deployed to Beijing Kingfore heating management system to validate the flexibility, efficacy and convenience of our approach for massive coding and large-scale system management in reality.
基金Supported by the National Natural Science Foundation of China(21076202)
文摘In order to improve the energy efficiency, reduce the CO2 emission and decrease the cost, a cogenera- tion system for desalination water, heat and power production was studied in this paper. The superstructure of the cogeneration system consisted of a coal-based thermal power plant （TPP）, a multi-stage flash desalination （MSF） module and reverse osmosis desalination （RO） module. For different demands of water, heat and power production, the corresponding optimal production structure was different. After reasonable simplification, the process model ot each unit was built. The economical model, including the unit investment, and operation and maintenance cost, was presented. By solving this non-linear programming （NLP） model, whose objective is to minimize the annual cost, an optimal cogeneration system can be obtained. Compared to separate production systems, the optimal system can reduce 16.1%-21.7% of the total annual cost. showing this design method was effective.
基金supported by the National Natural Science Foundation of China (Nos.50705084 and 60473129)the Science and Technology Plan of Zhejiang Province,China (No.2007C13018)
文摘The specification of authorization policies in access control models proposed so far cannot satisfy the requirements in workflow management systems(WFMSs).Furthermore,existing approaches have not provided effective conflict detection and resolution methods to maintain the consistency of authorization polices in WFMSs.To address these concerns,we propose the definition of authorization policies in which context constraints are considered and the complicated requirements in WFMSs can be satisfied.Based on the definition,we put forward static and dynamic conflict detection methods for authorization policies.By defining two new concepts,the precedence establishment rule and the conflict resolution policy,we provide a flexible approach to resolving conflicts.
基金supported by the China Postdoctoral Science Foundation (No. 20070410683).
文摘The authors study radial solutions to a model equation for the Navier-Stokes equations. It is shown that the model equation has self-similar singular solution if 5 ≤ n ≤ 9. It is also shown that the solution will blow up if the initial data is radial, large enough and n ≥ 5.
