The geological hazards, such as water inrush and mud outburst, are easily induced by the high water pressure caverns ahead of a karst tunnel face. Therefore, it is a pivotal issue to determine the reserved thickness o...The geological hazards, such as water inrush and mud outburst, are easily induced by the high water pressure caverns ahead of a karst tunnel face. Therefore, it is a pivotal issue to determine the reserved thickness of rock plug during the construction of tunnels. The limit analysis principle is employed to analyze the safe thickness from the point of energy dissipation, and the nonlinear and non-associated characteristics of geotechnical materials are both considered. On the basis of a plane failure pattern of rock plug, the expressions of detaching curve and rock plug thickness are derived. The effect of each parameter on the safe thickness of rock plug is discussed in detail, which interprets the corresponding failure scope of rock plug. The obtained results indicate that the thickness of rock plug is highly influenced by the nonlinear dilatancy coefficient and the nonlinear coefficient. The proposed method is validated by a comparison of the calculated results with those of the engineering project of the "526 karst cavern" of Yunwushan tunnel. This proposed method can provide reference basis for the design and excavation of karst tunnels in the future.展开更多
Incremental data mining is an attractive goal for many kinds of mining in large databases or data warehouses. A new incremental updating algorithm rule growing algorithm (RGA) is presented for efficient maintenance di...Incremental data mining is an attractive goal for many kinds of mining in large databases or data warehouses. A new incremental updating algorithm rule growing algorithm (RGA) is presented for efficient maintenance discovered association rules when new transaction data is added to a transaction database. The algorithm RGA makes use of previous association rules as seed rules. By RGA, the seed rules whether are strong or not can be confirmed without scanning all the transaction DB in most cases. If the distributing of item of transaction DB is not uniform, the inflexion of robustness curve comes very quickly, and RGA gets great efficiency, saving lots of time for I/O. Experiments validate the algorithm and the test results showed that this algorithm is efficient.展开更多
In 1966, Imai, Y. and the latter author of this paper introduced the BCK-algebra in the following Definition 1. Let X be a set with a binary operation * and a constant 0. Then X is called a BCK-algebra, if it satisfie...In 1966, Imai, Y. and the latter author of this paper introduced the BCK-algebra in the following Definition 1. Let X be a set with a binary operation * and a constant 0. Then X is called a BCK-algebra, if it satisfies the following conditions: (ⅰ) (x*y)*(x*展开更多
On sait qu’un espace local homogène formé de l’algèbre de Lie réelle g et sa sousalgèbre g1 est dit symétrique （E.L.S.）lorsque g1 est composé des éléments invariants d...On sait qu’un espace local homogène formé de l’algèbre de Lie réelle g et sa sousalgèbre g1 est dit symétrique （E.L.S.）lorsque g1 est composé des éléments invariants d’un automorphisme involutif σ de g. On se borne ici àétudier le cas où g est une algèbre de Lie simple qui a une décomposition de Cartan g=k+p. D’après M. Berger, nous savons que tout automorphisme involutif展开更多
基金Project(2013CB036004) supported by the National Basic Research Program of ChinaProjects(51378510,51308072) supported by National Natural Science Foundation of ChinaProject(CX2014B069) supported by the Hunan Provincial Innovation Foundation for Postgraduate,China
文摘The geological hazards, such as water inrush and mud outburst, are easily induced by the high water pressure caverns ahead of a karst tunnel face. Therefore, it is a pivotal issue to determine the reserved thickness of rock plug during the construction of tunnels. The limit analysis principle is employed to analyze the safe thickness from the point of energy dissipation, and the nonlinear and non-associated characteristics of geotechnical materials are both considered. On the basis of a plane failure pattern of rock plug, the expressions of detaching curve and rock plug thickness are derived. The effect of each parameter on the safe thickness of rock plug is discussed in detail, which interprets the corresponding failure scope of rock plug. The obtained results indicate that the thickness of rock plug is highly influenced by the nonlinear dilatancy coefficient and the nonlinear coefficient. The proposed method is validated by a comparison of the calculated results with those of the engineering project of the "526 karst cavern" of Yunwushan tunnel. This proposed method can provide reference basis for the design and excavation of karst tunnels in the future.
基金The work is supported by Chongqing Municipal Education Commission Science Research Program( No.KJ060511)
文摘Incremental data mining is an attractive goal for many kinds of mining in large databases or data warehouses. A new incremental updating algorithm rule growing algorithm (RGA) is presented for efficient maintenance discovered association rules when new transaction data is added to a transaction database. The algorithm RGA makes use of previous association rules as seed rules. By RGA, the seed rules whether are strong or not can be confirmed without scanning all the transaction DB in most cases. If the distributing of item of transaction DB is not uniform, the inflexion of robustness curve comes very quickly, and RGA gets great efficiency, saving lots of time for I/O. Experiments validate the algorithm and the test results showed that this algorithm is efficient.
文摘In 1966, Imai, Y. and the latter author of this paper introduced the BCK-algebra in the following Definition 1. Let X be a set with a binary operation * and a constant 0. Then X is called a BCK-algebra, if it satisfies the following conditions: (ⅰ) (x*y)*(x*
文摘On sait qu’un espace local homogène formé de l’algèbre de Lie réelle g et sa sousalgèbre g1 est dit symétrique （E.L.S.）lorsque g1 est composé des éléments invariants d’un automorphisme involutif σ de g. On se borne ici àétudier le cas où g est une algèbre de Lie simple qui a une décomposition de Cartan g=k+p. D’après M. Berger, nous savons que tout automorphisme involutif
