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Evolvement of the System Complexity Degree under Different Time Scalings:an Illustration of the Traffic Flow System 被引量:1
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作者 刘峰涛 姚卫新 《Journal of Donghua University(English Edition)》 EI CAS 2008年第2期241-244,共4页
It is investigable how the system scaling affects the system complexity degree. The traffic flow system is taken in this paper as an illustration to study this question. First, the Lempel-Ziv algorithm is introduced f... It is investigable how the system scaling affects the system complexity degree. The traffic flow system is taken in this paper as an illustration to study this question. First, the Lempel-Ziv algorithm is introduced for accurate depiction of the complexity degree of the traffic flow system. We gain 3 actual sequences and 20s period traffic flow sequences on the basis of the measure of the traffic flow data; we gain 5 traffic flow sequences whose periods are between 1-5min by simulating the traffic flow system. By calculating the complicacy of the 11 sequences, we obtain two hypothesis: the complicacies of the same system are different under different time scalings; negative correlation exists between the complicacy and the time scaling of the system. 展开更多
关键词 complexity degree SYSTEM SCALING evolvement
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Evaluaton model for the geometry complexity of casting based on fuzzy theory 被引量:1
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作者 吴士平 徐琴 +1 位作者 薛祥 吴光然 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2012年第4期9-12,共4页
The parameters that describe the complex degree of a certain casting are of some uncertainty. Therefore, a new method based on the fuzzy theory to classify the complex degree of castings has been presented in this pap... The parameters that describe the complex degree of a certain casting are of some uncertainty. Therefore, a new method based on the fuzzy theory to classify the complex degree of castings has been presented in this paper. The feasibility of fuzzy theory in describing the complex degree of castings has been discussed and the procedure of this method has been specified by analyzing the complex degrees of some typical castings. The element factors that influence the casting complexity, have been summarized, which include the wall-thickness and the number of transition surface, etc. The results show that it is reasonable and practicable to classify the complex degree of castings with the fuzzy theory. 展开更多
关键词 fuzzy theory CASTING complex degree GEOMETRY evaluation model
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Effect of Rice-Based Cropping System on Organic Matter Status in Soils 被引量:1
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作者 XIAO YONGLAN ZHANG YANGZHU +3 位作者 HU RUIZHI HUANG YUNXIANG ZHOUQING YUAN ZHENGPING( Department of Natural Resources, Hunan Agricultural University, Changsha 410128 (China)) YANG DONGPING( Soil and Fertilizer Center of Northern District of Yueyang Municipali 《Pedosphere》 SCIE CAS CSCD 1997年第4期349-354,共6页
A long-term simulation experiment was carried out to study the effect of rice-based cropping system,green manure and ground-water level on soil organic matter. Soil organic matter content increased when upland soil wa... A long-term simulation experiment was carried out to study the effect of rice-based cropping system,green manure and ground-water level on soil organic matter. Soil organic matter content increased when upland soil was puddled and cropped under submerged conditions. Among all treatments, soil organic matter contents in the treatments of rice-rice-flooded fallow in winter (WF) were the highest, those in the treatments of rice-rice-astragalus (WG) came the second, and those in the treatments of rice-rice-rape (WR)were the lowest. At the same rate of green manure application, the degrees of organo-mineral complexing in soils of treatments WG and WR were higher than those of treatment WF. After 9-year rice cultivation, the state of combination of humus in heavy fraction varied with treatments. The relative content of loosely bonded humus decreased in the order of WR > WG > WF, and it correlated significantly with Se availability. 展开更多
关键词 degree of organo-mineral complexing organic matter rice-based cropping system Se availability
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Acyclic colorings of graphs with bounded degree 被引量:2
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作者 FIEDOROWICZ Anna SIDOROWICZ Elzbieta 《Science China Mathematics》 SCIE CSCD 2016年第7期1427-1440,共14页
A k coloring(not necessarily proper) of vertices of a graph is called acyclic, if for every pair of distinct colors i and j the subgraph induced by the edges whose endpoints have colors i and j is acyclic. We consider... A k coloring(not necessarily proper) of vertices of a graph is called acyclic, if for every pair of distinct colors i and j the subgraph induced by the edges whose endpoints have colors i and j is acyclic. We consider some generalized acyclic k colorings, namely, we require that each color class induces an acyclic or bounded degree graph. Mainly we focus on graphs with maximum degree 5. We prove that any such graph has an acyclic 5 coloring such that each color class induces an acyclic graph with maximum degree at most 4. We prove that the problem of deciding whether a graph G has an acyclic 2 coloring in which each color class induces a graph with maximum degree at most 3 is NP complete, even for graphs with maximum degree 5. We also give a linear time algorithm for an acyclic t improper coloring of any graph with maximum degree d assuming that the number of colors is large enough. 展开更多
关键词 acyclic coloring bounded degree graph computational complexity
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