Focusing on the stability of surrounding rock around the roadway driving along next goaf with a narrow coal pillar, a mechanics model of the triangle block structure of main roof above the roadway is established, and ...Focusing on the stability of surrounding rock around the roadway driving along next goaf with a narrow coal pillar, a mechanics model of the triangle block structure of main roof above the roadway is established, and the sliding stability coefficient K 1 and the rotation stability coefficient K 2 are proposed to describe the stability of the triangle block structure quantitatively. The structure can keep a self stability before and after the roadway excavation, at the stage of mining induced effect, the stability of the structure is lowered, and the structure may become instability with decreasing the coal strength, increasing the mining height of working face and the mining depth.展开更多
A homogeneous and lattice self-reconfigurable robot module is designed, and each module is composed of a center body and six connection planes which can independently rotate. A module can independently connect or disc...A homogeneous and lattice self-reconfigurable robot module is designed, and each module is composed of a center body and six connection planes which can independently rotate. A module can independently connect or disconnect with other modules, and then change its connection by collaborating with other modules. We discuss how to describe and discover configuration of robot. Furthermore, we describe its motion planning based on the appraisal function and the adjacency matrix which is effective to solve the computationally difficult problem and optimize the system motion path during the self-reconfiguration process. Finally, a simulation experiment is demonstrated, which verifies the correctness of locomotion method.展开更多
This paper discribes the importance and necessity of the study on the data structures for displaying the mining field using the interactive technology in open pit design and planning,based upon the grid block model. T...This paper discribes the importance and necessity of the study on the data structures for displaying the mining field using the interactive technology in open pit design and planning,based upon the grid block model. The commonly used data structures--rectangular array structure and quadtree structure ,are analyzed. Two compressed data structures--compressed circular link array structure and compressed doubly-linked circular array structure,are proposed,which are much more suitable for displaying the regularly gridded block model. When the two compressed data structures are adopted,the storage space can be tremendously saved and the algorithms are simple,while the requirements of the accuracy and the manipulating speed will be both satisfied for the interactive open pit short range plan formulation.展开更多
In this paper new criteria for designing of temporary architectures, which can be used as a uniform coverage for open spaces, are discussed. Frequently temporary architectures use building techniques and materials lig...In this paper new criteria for designing of temporary architectures, which can be used as a uniform coverage for open spaces, are discussed. Frequently temporary architectures use building techniques and materials lightweight. In the case of temporary architectures the theme of sustainability requires that the structure can be reused in different occasions and contexts. The solution to these issues, developed in this paper, makes use of a innovative constructive procedure of prestressed masonry in blocks of natural stone. This procedure is used for the construction of the vertical supports of the cover, consisting of a tensostructure with shape of hyperboloid, obtained by products standard （steel profiles and membrane）. The columns with prestressed blocks of natural stone, dry assembled, allow you to have a modular structure, easily assembled and disassembled, with full recovery of all elements; the stone columns, due to their weight, are able to stabilize the whole structure, even to the dynamic stresses, without using any type of foundation structure fixed to the ground. This paper shows the description of all the elements that make up the new type of temporary architecture designed.展开更多
Numerical simulation on conjugate heat transfer of an internal cooled turbine vane was carried out. Numerical techniques employed included the third-order accuracy TVD scheme, multi-block structured grids and the tech...Numerical simulation on conjugate heat transfer of an internal cooled turbine vane was carried out. Numerical techniques employed included the third-order accuracy TVD scheme, multi-block structured grids and the technique of arbitrary curved mesh. Comparison between results of commercial CFD codes with several turbulence models and those of this code shows that it is incorrect of commercial CFD codes to predict the thermal boundary layer with traditional turbulence models, and that turbulence models considering transition lead to more accurate heat transfer in thermal boundary layer with some reliability and deficiency yet. The results of this code are close to those of CFX with transition model.展开更多
Bodies of plants are modularly organized. Development proceeds by adding new modules to open endings with a potential for branching. Each module is autonomous to some extent. Development relies on the self-organized p...Bodies of plants are modularly organized. Development proceeds by adding new modules to open endings with a potential for branching. Each module is autonomous to some extent. Development relies on the self-organized patterns that emerge from the interactions of individual modules. Interactions include both competition and cooperation,and several types of positive and negative feedback loops are involved. Development can be open to external influences, thus enabling the plant to adjust its form to the environment,for example, to the spatial distribution of ecological resources. This paper provides a review on adaptive plasticity in plants.展开更多
文摘Focusing on the stability of surrounding rock around the roadway driving along next goaf with a narrow coal pillar, a mechanics model of the triangle block structure of main roof above the roadway is established, and the sliding stability coefficient K 1 and the rotation stability coefficient K 2 are proposed to describe the stability of the triangle block structure quantitatively. The structure can keep a self stability before and after the roadway excavation, at the stage of mining induced effect, the stability of the structure is lowered, and the structure may become instability with decreasing the coal strength, increasing the mining height of working face and the mining depth.
文摘A homogeneous and lattice self-reconfigurable robot module is designed, and each module is composed of a center body and six connection planes which can independently rotate. A module can independently connect or disconnect with other modules, and then change its connection by collaborating with other modules. We discuss how to describe and discover configuration of robot. Furthermore, we describe its motion planning based on the appraisal function and the adjacency matrix which is effective to solve the computationally difficult problem and optimize the system motion path during the self-reconfiguration process. Finally, a simulation experiment is demonstrated, which verifies the correctness of locomotion method.
文摘This paper discribes the importance and necessity of the study on the data structures for displaying the mining field using the interactive technology in open pit design and planning,based upon the grid block model. The commonly used data structures--rectangular array structure and quadtree structure ,are analyzed. Two compressed data structures--compressed circular link array structure and compressed doubly-linked circular array structure,are proposed,which are much more suitable for displaying the regularly gridded block model. When the two compressed data structures are adopted,the storage space can be tremendously saved and the algorithms are simple,while the requirements of the accuracy and the manipulating speed will be both satisfied for the interactive open pit short range plan formulation.
文摘In this paper new criteria for designing of temporary architectures, which can be used as a uniform coverage for open spaces, are discussed. Frequently temporary architectures use building techniques and materials lightweight. In the case of temporary architectures the theme of sustainability requires that the structure can be reused in different occasions and contexts. The solution to these issues, developed in this paper, makes use of a innovative constructive procedure of prestressed masonry in blocks of natural stone. This procedure is used for the construction of the vertical supports of the cover, consisting of a tensostructure with shape of hyperboloid, obtained by products standard （steel profiles and membrane）. The columns with prestressed blocks of natural stone, dry assembled, allow you to have a modular structure, easily assembled and disassembled, with full recovery of all elements; the stone columns, due to their weight, are able to stabilize the whole structure, even to the dynamic stresses, without using any type of foundation structure fixed to the ground. This paper shows the description of all the elements that make up the new type of temporary architecture designed.
基金Sponsored by the National Natural Science Foundation of China (Grant No.5047028 and 50476017)
文摘Numerical simulation on conjugate heat transfer of an internal cooled turbine vane was carried out. Numerical techniques employed included the third-order accuracy TVD scheme, multi-block structured grids and the technique of arbitrary curved mesh. Comparison between results of commercial CFD codes with several turbulence models and those of this code shows that it is incorrect of commercial CFD codes to predict the thermal boundary layer with traditional turbulence models, and that turbulence models considering transition lead to more accurate heat transfer in thermal boundary layer with some reliability and deficiency yet. The results of this code are close to those of CFX with transition model.
基金This research was subsidized by the Hungarian National Research Fund(OTKA T35009,and NWOOTKA N34028),the Hungarian Ministry of Education(FKFP 0187/1990,Istvn Szchenyi Scolarship),and the International Program of the Santa Fe Institute,NM,USA.
文摘Bodies of plants are modularly organized. Development proceeds by adding new modules to open endings with a potential for branching. Each module is autonomous to some extent. Development relies on the self-organized patterns that emerge from the interactions of individual modules. Interactions include both competition and cooperation,and several types of positive and negative feedback loops are involved. Development can be open to external influences, thus enabling the plant to adjust its form to the environment,for example, to the spatial distribution of ecological resources. This paper provides a review on adaptive plasticity in plants.
