A method for optimizing automotive doors under multiple criteria involving the side impact, stiffness, natural frequency, and structure weight is presented. Metamodeling technique is employed to construct approximatio...A method for optimizing automotive doors under multiple criteria involving the side impact, stiffness, natural frequency, and structure weight is presented. Metamodeling technique is employed to construct approximations to replace the high computational simulation models. The approximating functions for stiffness and natural frequency are constructed using Taylor series approximation. Three popular approximation techniques,i.e.polynomial response surface (PRS), stepwise regression (SR), and Kriging are studied on their accuracy in the construction of side impact functions. Uniform design is employed to sample the design space of the door impact analysis. The optimization problem is solved by a multi-objective genetic algorithm. It is found that SR technique is superior to PRS and Kriging techniques in terms of accuracy in this study. The numerical results demonstrate that the method successfully generates a well-spread Pareto optimal set. From this Pareto optimal set, decision makers can select the most suitable design according to the vehicle program and its application.展开更多
Calcium sulfoaluminate,3CaO·3Al2O3·CaSO4,has been widely recognized in the realms of high-temperature combustion and cement chemistry.However,the lack of relevant thermodynamic data limits the progress of it...Calcium sulfoaluminate,3CaO·3Al2O3·CaSO4,has been widely recognized in the realms of high-temperature combustion and cement chemistry.However,the lack of relevant thermodynamic data limits the progress of its research and development.Through comparative calculations using several different approaches,we obtain the thermochemical properties of 3CaO·3Al2O3·CaSO4 in this work,such as its standard formation enthalpy,Gibbs free en- ergy of formation,entropy,and molar heat capacity.With these fundamental data,thermodynamic calculations become possible for reactions involving this mineral.It is found that some reactions proposed in literature to generate this mineral may not proceed thermodynamically.展开更多
On the example of copper fulvate, it is discussed the method of calculation of stability constants of fulvic complexes. At pH = 8, the complex formation of copper（ll） ions with fulvic acids was studied by the solubi...On the example of copper fulvate, it is discussed the method of calculation of stability constants of fulvic complexes. At pH = 8, the complex formation of copper（ll） ions with fulvic acids was studied by the solubility method. Fulvic acids were separated from the river Mtkvari by the adsorption-chromotographic method. The charcoal （BAU, Russia） was used as a sorbent. The suspension of copper（If） hydroxide was used as the solid phase, on which was added the increasing quantity of standard solution of fulvic acids. In diluted solutions, at pH = 8 the dominant form of copper（lI） is copper dihydroxo complex Cu（OH）^zO. It was established that in the Cu（OH）2 （solid）-Cu（OH）^20 （solution）-FA^2-H20 system, dominates copper dyhydroxo fulvate complex with the structure 1：1, [Cu（OH）2FA]^2. The average stability constant of copper dyhydroxo fulvate complex was calculated based on experimental data fl [Cu（OH）2FAJ^2 = 4.5× l0^5.展开更多
The present study investigates computer-antomated design and structural optimization of concrete slab frame bridges considering investment cost based on a complete 3D model. Thus, a computer code with several modules ...The present study investigates computer-antomated design and structural optimization of concrete slab frame bridges considering investment cost based on a complete 3D model. Thus, a computer code with several modules has been developed to produce parametric models of slab frame bridges. Design loads and load combinations are based on the Eurocode design standard and the Swedish design standard for bridges. The necessary reinforcement diagrams to satisfy the ultimate and serviceability limit states, including fatigue checks for the whole bridge, are calculated according to the aforementioned standards. Optimization techniques based on the genetic algorithm and the pattern search method are applied. A case study is presented to highlight the efficiency of the applied optimization algorithms. This methodology has been applied in the design process for the time-effective, material-efficient, and optimal design of concrete slab frame bridges.展开更多
In this paper,a detailed data list of water plan is given,based on its characteristics.This paper discusses the principles ofestablishing a system of standards for a water plan database,and amethod of modeling the wat...In this paper,a detailed data list of water plan is given,based on its characteristics.This paper discusses the principles ofestablishing a system of standards for a water plan database,and amethod of modeling the water plan data.The information is presentedin a standardization system graph.展开更多
基金Supported by National"863"Program of China (No.2006AA04Z127) .
文摘A method for optimizing automotive doors under multiple criteria involving the side impact, stiffness, natural frequency, and structure weight is presented. Metamodeling technique is employed to construct approximations to replace the high computational simulation models. The approximating functions for stiffness and natural frequency are constructed using Taylor series approximation. Three popular approximation techniques,i.e.polynomial response surface (PRS), stepwise regression (SR), and Kriging are studied on their accuracy in the construction of side impact functions. Uniform design is employed to sample the design space of the door impact analysis. The optimization problem is solved by a multi-objective genetic algorithm. It is found that SR technique is superior to PRS and Kriging techniques in terms of accuracy in this study. The numerical results demonstrate that the method successfully generates a well-spread Pareto optimal set. From this Pareto optimal set, decision makers can select the most suitable design according to the vehicle program and its application.
基金Supported by the National Natural Science Foundation of China(50906046)the National High-Tech Research and Development Program of China(2009AA05Z303)the Program for New Century Excellent Talents in University(NCET-10-0529)
文摘Calcium sulfoaluminate,3CaO·3Al2O3·CaSO4,has been widely recognized in the realms of high-temperature combustion and cement chemistry.However,the lack of relevant thermodynamic data limits the progress of its research and development.Through comparative calculations using several different approaches,we obtain the thermochemical properties of 3CaO·3Al2O3·CaSO4 in this work,such as its standard formation enthalpy,Gibbs free en- ergy of formation,entropy,and molar heat capacity.With these fundamental data,thermodynamic calculations become possible for reactions involving this mineral.It is found that some reactions proposed in literature to generate this mineral may not proceed thermodynamically.
文摘On the example of copper fulvate, it is discussed the method of calculation of stability constants of fulvic complexes. At pH = 8, the complex formation of copper（ll） ions with fulvic acids was studied by the solubility method. Fulvic acids were separated from the river Mtkvari by the adsorption-chromotographic method. The charcoal （BAU, Russia） was used as a sorbent. The suspension of copper（If） hydroxide was used as the solid phase, on which was added the increasing quantity of standard solution of fulvic acids. In diluted solutions, at pH = 8 the dominant form of copper（lI） is copper dihydroxo complex Cu（OH）^zO. It was established that in the Cu（OH）2 （solid）-Cu（OH）^20 （solution）-FA^2-H20 system, dominates copper dyhydroxo fulvate complex with the structure 1：1, [Cu（OH）2FA]^2. The average stability constant of copper dyhydroxo fulvate complex was calculated based on experimental data fl [Cu（OH）2FAJ^2 = 4.5× l0^5.
文摘The present study investigates computer-antomated design and structural optimization of concrete slab frame bridges considering investment cost based on a complete 3D model. Thus, a computer code with several modules has been developed to produce parametric models of slab frame bridges. Design loads and load combinations are based on the Eurocode design standard and the Swedish design standard for bridges. The necessary reinforcement diagrams to satisfy the ultimate and serviceability limit states, including fatigue checks for the whole bridge, are calculated according to the aforementioned standards. Optimization techniques based on the genetic algorithm and the pattern search method are applied. A case study is presented to highlight the efficiency of the applied optimization algorithms. This methodology has been applied in the design process for the time-effective, material-efficient, and optimal design of concrete slab frame bridges.
文摘In this paper,a detailed data list of water plan is given,based on its characteristics.This paper discusses the principles ofestablishing a system of standards for a water plan database,and amethod of modeling the water plan data.The information is presentedin a standardization system graph.
