In mine ventilation networks, the reasonable airflow distribution is very important for the production safety and economy. Three basic problems of the natural, full-controlled and semi-controlled splitting were review...In mine ventilation networks, the reasonable airflow distribution is very important for the production safety and economy. Three basic problems of the natural, full-controlled and semi-controlled splitting were reviewed in the paper. Aiming at the high difficulty semi-controlled splitting problem, the general nonlinear multi-objectives optimization mathematical model with constraints was established based on the theory of mine ventilation networks. A new algorithm, which combined the improved differential evaluation and the critical path method (CPM) based on the multivariable separate solution strategy, was put forward to search for the global optimal solution more efficiently. In each step of evolution, the feasible solutions of air quantity distribution are firstly produced by the improved differential evolu- tion algorithm, and then the optimal solutions of regulator pressure drop are obtained by the CPM. Through finite steps iterations, the optimal solution can be given. In this new algorithm, the population of feasible solutions were sorted and grouped for enhancing the global search ability and the individuals in general group were randomly initialized for keeping diversity. Meanwhile, the individual neighbor- hood in the fine group which may be closely to the optimal solutions were searched locally and slightly for achieving a balance between global searching and local searching, thus improving the convergence rate. The computer program was developed based on this method. Finally, the two ventilation networks with single-fan and multi-fans were solved. The results show that this algorithm has advantages of high effectiveness, fast convergence, good robustness and flexibility. This computer program could be used to solve lar^e-scale ~eneralized ventilation networks o^timization problem in the future.展开更多
In this paper, the relations of the network topology and the moving consensus of multi-agent systems are studied. A consensus-prestissimo scale-free network model with the static preferential-consensus attachment is p...In this paper, the relations of the network topology and the moving consensus of multi-agent systems are studied. A consensus-prestissimo scale-free network model with the static preferential-consensus attachment is presented on the rewired link of the regular network. The effects of the static preferential-consensus BA network on the algebraic connectivity of the topology graph are compared with the regular network. The robustness gain to delay is analyzed for variable network topology with the same scale. The time to reach the consensus is studied for the dynamic network with and without communication delays. By applying the computer simulations, it is validated that the speed of the convergence of multi-agent systems can be greatly improved in the preferential-consensus BA network model with different configuration.展开更多
City regions often have great diversity in form and function. To better understand the role of each region, the relations between city regions need to be carefully studied. In this work, the human mobility relations b...City regions often have great diversity in form and function. To better understand the role of each region, the relations between city regions need to be carefully studied. In this work, the human mobility relations between regions of Shanghai based on mobile phone data is explored. By formulating the regions as nodes in a network and the commuting between each pair of regions as link weights, the distribution of nodes degree, and spatial structures of communities in this relation network are studied. Statistics show that regions locate in urban centers and traffic hubs have significantly larger degrees. Moreover, two kinds of spatial structures of communities are found. In most communities, nodes are spatially neighboring. However, in the communities that cover traffic hubs, nodes often locate along corridors.展开更多
There seems to be a renewed interest in the last couple decades in studying and writing about consciousness. Consciousness may be the most difficult question humans are trying to resolve. Yet eliciting transcendence, ...There seems to be a renewed interest in the last couple decades in studying and writing about consciousness. Consciousness may be the most difficult question humans are trying to resolve. Yet eliciting transcendence, a phenomenon that rises above, or goes beyond, normal limits of consciousness, has been an identified goal for many artists in the past, possibly even in cave art. Drawing on works shown in the 2006 Art Gallery of Hamilton exposition called Sublime Embrace: Experiencing Consciousness in Contemporary Art and in the 2002 Houston Contemporary Art Museum 2002 show called THE INWARD EYE: Transcendence in Contemporary Art, the author will explore the biological, psychological, cultural, and spiritual facets of transcendence. Perhaps, with the renewed symbiotic relationship between the sciences and art, the convergence of digital media, and the emergence of global communication networks, we are at the verge of art that will create a change, an alteration in our consciousness, and an altercendent state. What this change will be is yet a mystery.展开更多
基金financially supported by the National Natural Science Foundation of China (No. 51134023)
文摘In mine ventilation networks, the reasonable airflow distribution is very important for the production safety and economy. Three basic problems of the natural, full-controlled and semi-controlled splitting were reviewed in the paper. Aiming at the high difficulty semi-controlled splitting problem, the general nonlinear multi-objectives optimization mathematical model with constraints was established based on the theory of mine ventilation networks. A new algorithm, which combined the improved differential evaluation and the critical path method (CPM) based on the multivariable separate solution strategy, was put forward to search for the global optimal solution more efficiently. In each step of evolution, the feasible solutions of air quantity distribution are firstly produced by the improved differential evolu- tion algorithm, and then the optimal solutions of regulator pressure drop are obtained by the CPM. Through finite steps iterations, the optimal solution can be given. In this new algorithm, the population of feasible solutions were sorted and grouped for enhancing the global search ability and the individuals in general group were randomly initialized for keeping diversity. Meanwhile, the individual neighbor- hood in the fine group which may be closely to the optimal solutions were searched locally and slightly for achieving a balance between global searching and local searching, thus improving the convergence rate. The computer program was developed based on this method. Finally, the two ventilation networks with single-fan and multi-fans were solved. The results show that this algorithm has advantages of high effectiveness, fast convergence, good robustness and flexibility. This computer program could be used to solve lar^e-scale ~eneralized ventilation networks o^timization problem in the future.
基金Supported in part by Chinese National Natural Science Foundation under Grant Nos. 60774016 60875039+2 种基金 60904022 60805039the Science Foundation of Education Office of Shandong Province of China under Grant No. J08LJ01
文摘In this paper, the relations of the network topology and the moving consensus of multi-agent systems are studied. A consensus-prestissimo scale-free network model with the static preferential-consensus attachment is presented on the rewired link of the regular network. The effects of the static preferential-consensus BA network on the algebraic connectivity of the topology graph are compared with the regular network. The robustness gain to delay is analyzed for variable network topology with the same scale. The time to reach the consensus is studied for the dynamic network with and without communication delays. By applying the computer simulations, it is validated that the speed of the convergence of multi-agent systems can be greatly improved in the preferential-consensus BA network model with different configuration.
基金Project(71303269)supported by the National Natural Science Foundation of ChinaProject(14ZZD006)supported by the Economics Major Research Task of Fostering,China
文摘City regions often have great diversity in form and function. To better understand the role of each region, the relations between city regions need to be carefully studied. In this work, the human mobility relations between regions of Shanghai based on mobile phone data is explored. By formulating the regions as nodes in a network and the commuting between each pair of regions as link weights, the distribution of nodes degree, and spatial structures of communities in this relation network are studied. Statistics show that regions locate in urban centers and traffic hubs have significantly larger degrees. Moreover, two kinds of spatial structures of communities are found. In most communities, nodes are spatially neighboring. However, in the communities that cover traffic hubs, nodes often locate along corridors.
文摘There seems to be a renewed interest in the last couple decades in studying and writing about consciousness. Consciousness may be the most difficult question humans are trying to resolve. Yet eliciting transcendence, a phenomenon that rises above, or goes beyond, normal limits of consciousness, has been an identified goal for many artists in the past, possibly even in cave art. Drawing on works shown in the 2006 Art Gallery of Hamilton exposition called Sublime Embrace: Experiencing Consciousness in Contemporary Art and in the 2002 Houston Contemporary Art Museum 2002 show called THE INWARD EYE: Transcendence in Contemporary Art, the author will explore the biological, psychological, cultural, and spiritual facets of transcendence. Perhaps, with the renewed symbiotic relationship between the sciences and art, the convergence of digital media, and the emergence of global communication networks, we are at the verge of art that will create a change, an alteration in our consciousness, and an altercendent state. What this change will be is yet a mystery.