The hybrid genetic algorithm is utilized to facilitate model parameter estimation.The tri-dimensional compression tests of soil are performed to supply experimental data for identifying nonlinear constitutive model of...The hybrid genetic algorithm is utilized to facilitate model parameter estimation.The tri-dimensional compression tests of soil are performed to supply experimental data for identifying nonlinear constitutive model of soil.In order to save computing time during parameter inversion,a new procedure to compute the calculated strains is presented by multi-linear simplification approach instead of finite element method(FEM).The real-coded hybrid genetic algorithm is developed by combining normal genetic algorithm with gradient-based optimization algorithm.The numerical and experimental results for conditioned soil are compared.The forecast strains based on identified nonlinear constitutive model of soil agree well with observed ones.The effectiveness and accuracy of proposed parameter estimation approach are validated.展开更多
Aggregate stability is a very important predictor of soil structure and strength, which influences soil erodibility. Several aggregate stability indices were selected erodibility of four soil properties from temperate...Aggregate stability is a very important predictor of soil structure and strength, which influences soil erodibility. Several aggregate stability indices were selected erodibility of four soil properties from temperate for estimating interrill types with contrasting and subtropical regions of China. This study was conducted to investigate how closely the soil interrill erodibility factor in the Water Erosion Prediction Project （WEPP） model relates to soil aggregate stability. The mass fractal dimension （FD）, geometric mean diameter （GMD）, mean weight diameter （MWD）, and aggregate stability index （ASI） of soil aggregates were calculated. A rainfall simulator with a drainable flume （3.0 m long × 1.0 m wide × 0.5 m deep） was used at four slope gradients （5°,10 °,15° and 20°）, and four rainfall intensities （0.6, 1.1, 1.7 and 2.5 mm/min）. Results indicated that the interriU erodibility （Ki） values were significantly correlated to the indices of ASI, MWD, GMD, and FD computed from the aggregate wet-sieve data. The Kihad a strong positive correlation with FD, as well as a strong negative correlation with ASI, GMD, and MWD. Soils with a higher aggregate stability and lower fractal dimension have smaller Ki values. Stable soils were characterized by a high percentage of large aggregates and the erodible soils by a high percentage of smaller aggregates. The correlation coefficients of Ki with ASI and GMD were greater than those with FD and MWD, implying that both the ASI and GMD may be better alternative parameters for empirically predicting the soil Ki factor. ASI and GMD are more reasonable in interrill soil erodibility estimation, compared with Ki calculation in original WEPP model equation. Results demonstrate the validation of soil aggregation characterization as an appropriate indicator of soil susceptibility to erosion in contrasting soil types in China.展开更多
Today, individuals can effectively use all kinds of communication tools with digital transformation. This transformation process is called ＂The Network Society＂ by Castells. According to Castells, people are living ...Today, individuals can effectively use all kinds of communication tools with digital transformation. This transformation process is called ＂The Network Society＂ by Castells. According to Castells, people are living with long cables or networks that connect each other. With the progressing and spreading technological advances, entertainment sector is booming since 1950s even more dramatically than the computer sector. Digital games sector, in this perspective, has been the intersection area of the entertainment sector and the computer sector. We can include to these three sectors a fourth one： Communication （or Media） sector. With the convergence of these four sectors, there is an enormous sea of possibilities, opportunities and problemles faced by humans. Our information society is turning into games. Today, the traditional understanding of play has been replaced by digital games. Digital games as an independent communication tool differ from traditional play in that they include a new communication medium into action. There is a different communication process in these digital games, which especially is an interest to younger generations. Digital games provide an interactive environment with individuals as they allow electiveness, mobility and non-linearity. In an era of economic angst and where real and virtual identities are being discussed, individuals of the information society are searching for something different other than mass communication. They seek after individual experiences. The main focus in this study will be to analyze the habits of play in digital games. The relationship between digital games and their users will also be examined. The quantitative study of digital games will be a useful source for future studies and will bridge the gap in this area.展开更多
基金Project(2007CB714006) supported by the National Basic Research Program of China Project(90815023) supported by the National Natural Science Foundation of China
文摘The hybrid genetic algorithm is utilized to facilitate model parameter estimation.The tri-dimensional compression tests of soil are performed to supply experimental data for identifying nonlinear constitutive model of soil.In order to save computing time during parameter inversion,a new procedure to compute the calculated strains is presented by multi-linear simplification approach instead of finite element method(FEM).The real-coded hybrid genetic algorithm is developed by combining normal genetic algorithm with gradient-based optimization algorithm.The numerical and experimental results for conditioned soil are compared.The forecast strains based on identified nonlinear constitutive model of soil agree well with observed ones.The effectiveness and accuracy of proposed parameter estimation approach are validated.
基金supported by the National Natural Science Foundation of China(Grant Nos.41271303,40901135)the National Key Technology R&D Program(Grant Nos.2012BAK10B04,2008BAD98B02)+2 种基金the Non-profit Industry Financial Program of MWR(Grant No.201301058)the Changjiang River Scientific Research Institute of Sciences Innovation Team Project(Grant No.CKSF2012052/TB)Central public welfare scientific research project(Grant No.CKSF2013013/TB)
文摘Aggregate stability is a very important predictor of soil structure and strength, which influences soil erodibility. Several aggregate stability indices were selected erodibility of four soil properties from temperate for estimating interrill types with contrasting and subtropical regions of China. This study was conducted to investigate how closely the soil interrill erodibility factor in the Water Erosion Prediction Project （WEPP） model relates to soil aggregate stability. The mass fractal dimension （FD）, geometric mean diameter （GMD）, mean weight diameter （MWD）, and aggregate stability index （ASI） of soil aggregates were calculated. A rainfall simulator with a drainable flume （3.0 m long × 1.0 m wide × 0.5 m deep） was used at four slope gradients （5°,10 °,15° and 20°）, and four rainfall intensities （0.6, 1.1, 1.7 and 2.5 mm/min）. Results indicated that the interriU erodibility （Ki） values were significantly correlated to the indices of ASI, MWD, GMD, and FD computed from the aggregate wet-sieve data. The Kihad a strong positive correlation with FD, as well as a strong negative correlation with ASI, GMD, and MWD. Soils with a higher aggregate stability and lower fractal dimension have smaller Ki values. Stable soils were characterized by a high percentage of large aggregates and the erodible soils by a high percentage of smaller aggregates. The correlation coefficients of Ki with ASI and GMD were greater than those with FD and MWD, implying that both the ASI and GMD may be better alternative parameters for empirically predicting the soil Ki factor. ASI and GMD are more reasonable in interrill soil erodibility estimation, compared with Ki calculation in original WEPP model equation. Results demonstrate the validation of soil aggregation characterization as an appropriate indicator of soil susceptibility to erosion in contrasting soil types in China.
文摘Today, individuals can effectively use all kinds of communication tools with digital transformation. This transformation process is called ＂The Network Society＂ by Castells. According to Castells, people are living with long cables or networks that connect each other. With the progressing and spreading technological advances, entertainment sector is booming since 1950s even more dramatically than the computer sector. Digital games sector, in this perspective, has been the intersection area of the entertainment sector and the computer sector. We can include to these three sectors a fourth one： Communication （or Media） sector. With the convergence of these four sectors, there is an enormous sea of possibilities, opportunities and problemles faced by humans. Our information society is turning into games. Today, the traditional understanding of play has been replaced by digital games. Digital games as an independent communication tool differ from traditional play in that they include a new communication medium into action. There is a different communication process in these digital games, which especially is an interest to younger generations. Digital games provide an interactive environment with individuals as they allow electiveness, mobility and non-linearity. In an era of economic angst and where real and virtual identities are being discussed, individuals of the information society are searching for something different other than mass communication. They seek after individual experiences. The main focus in this study will be to analyze the habits of play in digital games. The relationship between digital games and their users will also be examined. The quantitative study of digital games will be a useful source for future studies and will bridge the gap in this area.
