Stamping process,which is widely used in automobile,aerospace,machine-building industries,and etc.,is a creative process needing time and experiences.The lead time is mainly spent on stamping die design and manufactur...Stamping process,which is widely used in automobile,aerospace,machine-building industries,and etc.,is a creative process needing time and experiences.The lead time is mainly spent on stamping die design and manufacturing.As the ba- sis of die design,process design is a non-linearity and creative process,which can be solved by using the fuzzy synthetic evaluation. In this paper,the potential o f fuzzy synthetic evaluation for dealing with stamping process design was explored.The influencing factor set,factor weight set,evaluation set,single factor fuzzy evaluation matrix,and fuzzy synthetic evaluation scheme were studied.Finally,the washer part,considering forming equipment,part dimensions and other factors,was selected to testify the evaluation process.展开更多
This paper uses a Modified Soil-Plant-Atmosphere Scheme (MSPAS) to study the interaction between land surface and atmospheric boundary layer processes. The scheme is composed of two main parts: atmospheric boundary la...This paper uses a Modified Soil-Plant-Atmosphere Scheme (MSPAS) to study the interaction between land surface and atmospheric boundary layer processes. The scheme is composed of two main parts: atmospheric boundary layer processes and land surface processes. Compared with SiB and BATS, which are famous for their detailed parameterizations of physical variables, this simplified model is more convenient and saves much more computation time. Though simple, the feasibility of the model is well proved in this paper. The numerical simulation results from MSPAS show good agreement with reality. The scheme is used to obtain reasonable simulations for diurnal variations of heat balance, potential temperature of boundary layer, and wind field, and spatial distributions of temperature, specific humidity, vertical velocity, turbulence kinetic energy, and turbulence exchange coefficient over desert and oasis. In addition, MSPAS is used to simulate the interaction between desert and oasis at night, and again it obtains reasonable results. This indicates that MSPAS can be used to study the interaction between land surface processes and the atmospheric boundary layer over various underlying surfaces and can be extended for regional climate and numerical weather prediction study.展开更多
In this paper, we propose numerical schemes for stochastic differential equations driven by G-Lévy process under the G-expectation framework. By using G-Itôformula and G-expectation property, we propose ...In this paper, we propose numerical schemes for stochastic differential equations driven by G-Lévy process under the G-expectation framework. By using G-Itôformula and G-expectation property, we propose Euler scheme and Milstein scheme which have order-1.0 convergence rate. And two numerical experiments including Ornstein-Uhlenbeck and Black-Scholes cases are given.展开更多
文摘Stamping process,which is widely used in automobile,aerospace,machine-building industries,and etc.,is a creative process needing time and experiences.The lead time is mainly spent on stamping die design and manufacturing.As the ba- sis of die design,process design is a non-linearity and creative process,which can be solved by using the fuzzy synthetic evaluation. In this paper,the potential o f fuzzy synthetic evaluation for dealing with stamping process design was explored.The influencing factor set,factor weight set,evaluation set,single factor fuzzy evaluation matrix,and fuzzy synthetic evaluation scheme were studied.Finally,the washer part,considering forming equipment,part dimensions and other factors,was selected to testify the evaluation process.
基金supported by the National Natural Science Foundation of China (Grant No.40275004)the State Key Laboratory of Atmosphere Physics and Chemistry,and the City University of Hong Kong(Grant No.8780046)the City University of Hong Kong Strategic Research(Grant No.7001038)
文摘This paper uses a Modified Soil-Plant-Atmosphere Scheme (MSPAS) to study the interaction between land surface and atmospheric boundary layer processes. The scheme is composed of two main parts: atmospheric boundary layer processes and land surface processes. Compared with SiB and BATS, which are famous for their detailed parameterizations of physical variables, this simplified model is more convenient and saves much more computation time. Though simple, the feasibility of the model is well proved in this paper. The numerical simulation results from MSPAS show good agreement with reality. The scheme is used to obtain reasonable simulations for diurnal variations of heat balance, potential temperature of boundary layer, and wind field, and spatial distributions of temperature, specific humidity, vertical velocity, turbulence kinetic energy, and turbulence exchange coefficient over desert and oasis. In addition, MSPAS is used to simulate the interaction between desert and oasis at night, and again it obtains reasonable results. This indicates that MSPAS can be used to study the interaction between land surface processes and the atmospheric boundary layer over various underlying surfaces and can be extended for regional climate and numerical weather prediction study.
文摘In this paper, we propose numerical schemes for stochastic differential equations driven by G-Lévy process under the G-expectation framework. By using G-Itôformula and G-expectation property, we propose Euler scheme and Milstein scheme which have order-1.0 convergence rate. And two numerical experiments including Ornstein-Uhlenbeck and Black-Scholes cases are given.
