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21.
Cecil B. Read 《School science and mathematics》1969,69(9):778-780
22.
K.A. Mohamed G.C. King F.H. Read 《Journal of Electron Spectroscopy and Related Phenomena》1977,12(3):229-237
The lifetime of the (B3Σ+υ= 0, 1 state of the CN radical has been measured by the photon-photon delayed coincidence technique, the CN radical being produced by electron impact dissociation of acetonitrile. This is the first lifetime measurement in a free radical by this method. The optical cascade in the band spectrum of CN used for the present measurement is H2Πr - B2Σ+ - X2Σ+. The lifetime of the (B2Σ+)υ=0, 1 state in CN has been found to be 61.1 ± 7.6 ns. 相似文献
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Orderly algorithms for the generation of exhaustive lists of nonisomorphic graphs are discussed. The existence of orderly methods to generate the graphs with a given subgraph and without a given subgraph is established. This method can be used to list all the nonisomorphic subgraphs of a given graph, as well as to produce catalogs of Hamiltonian graphs, pancyclic graphs, degree-constrained graphs, and other classes. A generalization of this method is given that can be used to generate lists of graphs with given girth, planar graphs, k-colorable graphs, and k-connected graphs, for example. Finally, these observations are employed to generate restricted classes of digraphs, notably acyclic digraphs and poset digraphs. The generation of poset digraphs is shown to supply a practical orderly method for producing a catalog of lattices. Similar observations concerning vertex addition generation methods allow one to improve on existing methods for the generation of catalog of interval and circle graphs. 相似文献
25.
In this paper we show that two dynamical invariants, the second order Renyi entropy and the correlation dimension, can be estimated from recurrence plots (RPs) with arbitrary embedding dimension and delay. This fact is interesting as these quantities are even invariant if no embedding is used. This is an important advantage of RPs compared to other techniques of nonlinear data analysis. These estimates for the correlation dimension and entropy are robust and, moreover, can be obtained at a low numerical cost. We exemplify our results for the Rossler system, the funnel attractor and the Mackey-Glass system. In the last part of the paper we estimate dynamical invariants for data from some fluid dynamical experiments and confirm previous evidence for low dimensional chaos in this experimental system. 相似文献
26.
Lewis PT Davis CJ Cabell LA He M Read MW McCarroll ME Strongin RM 《Organic letters》2000,2(5):589-592
[structure: see text] Heating aqueous DMSO solutions of five saccharides in the presence of 1-3 reveals that each receptor promotes solution colors characteristic for each sugar. New compound 3 allows the direct correlation of sugar concentration with visible region absorbance and/or fluorescence intensities. 相似文献
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Dwight Read 《Computational & Mathematical Organization Theory》2010,16(4):329-347
The promise of agent-based for explicating properties of social systems has not yet been fully realized. Agent models sometimes
provide only a veneer of, rather than substantive engagement with, social behavior. The problem will be illustrated with Axelrod’s
model for evolution of ethnocentrism (a biological model) versus Schelling’s model for spatial segregation based on preferences
(a cultural model). The examples show the need to incorporate both the biological and cultural basis for behavior through
a schema that includes behavior based on cultural/cognitive processing of information and behavior based on biological/cognitive
processing of information. An example of an agent-based model that implements decision making in this manner is discussed.
The model accounts for heterogeneity in behavior outcomes and leads to two main predictions: (1) small scale, hunter-gatherer
societies in resource scarce environments will have stable adaptations less affected by variation in resource abundance in
comparison to groups in resource rich regions where inter-group conflict is more likely and (2) the relationship between community
size, population size and administrative complexity will have two distinct patterns, one for patrilineally organized societies
and the other for matrilineally organized societies. Both predictions have been verified empirically. 相似文献
29.
Ronald C. Read 《Aequationes Mathematicae》1986,31(1):47-63
A class of plane multigraphs having a series-parallel structure is defined and enumerated. The enumeration is carried out both for the rooted graphs as originally defined, and also for those where no distinctions are made between the vertices. Some other related problems are also discussed. 相似文献
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