Data flow diagram(DFD),as a special kind of data,is a design artifact in both requirement analysis and structured analysis in software development.However,rigorous analysis of DFD requires a formal semantics.Formal re...Data flow diagram(DFD),as a special kind of data,is a design artifact in both requirement analysis and structured analysis in software development.However,rigorous analysis of DFD requires a formal semantics.Formal representation of DFD and its formal semantics will help to reduce inconsistencies and confusion.The logical structure of DFD can be described using formalism of Calculus of Communicating System(CCS).With a finite number of states based on CCS,state space methods will help a lot in analysis and verification of the behavior of the systems.But the number of states of even a relatively small system is often very great that is called state explosion.In this paper,we present a visual system which combines Formal methods and visualization techniques so as to help the researchers to understand and analyze the system described by the DFD regardless of the problem of state explosion.展开更多
A stable and recyclable of BiOBr/silk fibroincellulose acetate composite film was prepared by blendingwet phase transformation and in situ precipitate technology.The cellulose acetate film modified by silk fibroin for...A stable and recyclable of BiOBr/silk fibroincellulose acetate composite film was prepared by blendingwet phase transformation and in situ precipitate technology.The cellulose acetate film modified by silk fibroin formed a finger-shaped porous structure,which provided a large space for the uniform growth of BiOBr nanosheets and facilitated the shuttle flow of dyes in film.The morphology,phase structure,and optical properties of the composite films were characterized using various techniques,and their photocatalytic performance for dye wastewater was evaluated under visible light irradiation.Results showed that the BiOBr/SF-CA composite film exhibited efficient photocatalytic activity with 99.9%of rhodamine B degradation rate.Moreover,the composite film maintained high catalytic stability because Bi as the active species deposited on the film showed almost no loss.Finally,the possible photocatalytic mechanisms in the BiOBr/SF-CA composite film were speculated through radical-trapping experiments and electron spin resonance testing.展开更多
文摘Data flow diagram(DFD),as a special kind of data,is a design artifact in both requirement analysis and structured analysis in software development.However,rigorous analysis of DFD requires a formal semantics.Formal representation of DFD and its formal semantics will help to reduce inconsistencies and confusion.The logical structure of DFD can be described using formalism of Calculus of Communicating System(CCS).With a finite number of states based on CCS,state space methods will help a lot in analysis and verification of the behavior of the systems.But the number of states of even a relatively small system is often very great that is called state explosion.In this paper,we present a visual system which combines Formal methods and visualization techniques so as to help the researchers to understand and analyze the system described by the DFD regardless of the problem of state explosion.
基金the financial support by the National Natural Science Foundation of China(Grant No.22202068)Natural Science Foundation in Hunan Province(Grant No.2021JJ30239)Natural Science Foundation for Distinguished Young Scholars in Hunan Province(Grant No.2020JJ2014).
文摘A stable and recyclable of BiOBr/silk fibroincellulose acetate composite film was prepared by blendingwet phase transformation and in situ precipitate technology.The cellulose acetate film modified by silk fibroin formed a finger-shaped porous structure,which provided a large space for the uniform growth of BiOBr nanosheets and facilitated the shuttle flow of dyes in film.The morphology,phase structure,and optical properties of the composite films were characterized using various techniques,and their photocatalytic performance for dye wastewater was evaluated under visible light irradiation.Results showed that the BiOBr/SF-CA composite film exhibited efficient photocatalytic activity with 99.9%of rhodamine B degradation rate.Moreover,the composite film maintained high catalytic stability because Bi as the active species deposited on the film showed almost no loss.Finally,the possible photocatalytic mechanisms in the BiOBr/SF-CA composite film were speculated through radical-trapping experiments and electron spin resonance testing.