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101.
102.
Melvyn B Nathanson 《Journal of Combinatorial Theory, Series A》1977,22(1):61-68
Let f: I → I be a continuous function on a closed interval I. If there exists x?I which has period 3 with respect to f, then Li and Yorke [1] proved that f is chaotic in the sense that there are not only points x?I of arbitrarily large period, but also uncountably many points x?I which are not even asymptotically periodic with respect to f. By using only elementary combinatorial facts about permutations, it is shown that if there is a point x?I of period p with respect to f, where p is divisible by 3, 5, or 7, then f is chaotic. The proof is followed by a study of some related combinatorial problems in symmetric groups. 相似文献
103.
Wilfried Imrich J.M.S Simões-Pereira Christina M Zamfirescu 《Journal of Combinatorial Theory, Series B》1984,36(1):1-15
This paper extends previous results of the authors. In particular, non-treerealizable metrics are investigated and it is shown that every finite metric has an optimal realization by a graph. 相似文献
104.
105.
106.
Anthony H. Jackson K. R. Nagaraja Rao N. Sim Ooi Esther Adelakun 《Tetrahedron letters》1984,25(52):6049-6050
Treatment of α-methylpyrroles with thallium (III) nitrate/Montmorillonite clay affords the corresponding α-formylpyrroles in excellent yields. 相似文献
107.
A frequency doubled Nd glass laser was used to irradiate plane solid targets. Temporally and spectrally resolved measurements of the backscattered light were obtained together with calorimeter measurements of the backreflected energy. The results show the presence of stimulated Brillouin scattering and an estimate is made of the coronal electron temperature. 相似文献
108.
A. P. C. Malbouisson F. R. A. Simão J. Sá Borges 《Zeitschrift fur Physik C Particles and Fields》1985,29(1):75-77
We give a naïve perturbative proof of the existence of infrared renormalons for large distance asymptotically free theories. We argue that the extension of the result for small distance asymptotically free theories is not obvious. Indeed we do not find infrared renormalons for QCD. 相似文献
109.
One of the shortcomings of R&D evaluation is a lack of emphasis on analytical assessment of the value of an on-going R&D project. This paper addresses the problem concerning the distributive aspect of access to superior knowledge. Decision tree analysis and probability models appear to be appropriate tools for assessing the values of an intermediate result and patent reward of a firm's R&D decision in an environment of perfect information and oligopolistic competition. The assessed values are used as minimum prices acceptable to the firm when the knowledge is disseminated to the public. This paper will attempt to resolve this problem through the determination of the appropriate values of the reservation price of the first-stage invention in terms of the final reward and of a patent reward for which the inventor is willing to apply. 相似文献
110.