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71.
The dynamic behaviour of the one-dimensional family of maps f(x)=c2[(a−1)x+c1]−λ/(α−1)f(x)=c2[(a1)x+c1]λ/(α1) is examined, for representative values of the control parameters a,c1a,c1, c2c2 and λλ. The maps under consideration are of special interest, since they are solutions of the relaxed Newton method derivative being equal to a constant aa. The maps f(x)f(x) are also proved to be solutions of a non-linear differential equation with outstanding applications in the field of power electronics. The recurrent form of these maps, after excessive iterations, shows, in an xnxn versus λλ plot, an initial exponential decay followed by a bifurcation. The value of λλ at which this bifurcation takes place depends on the values of the parameters a,c1a,c1 and c2c2. This corresponds to a switch to an oscillatory behaviour with amplitudes of f(x)f(x) undergoing a period doubling. For values of aa higher than 1 and at higher values of λλ a reverse bifurcation occurs. The corresponding branches converge and a bleb is formed for values of the parameter c1c1 between 1 and 1.20. This behaviour is confirmed by calculating the corresponding Lyapunov exponents.  相似文献   
72.
We prove a limit theorem for the argument of zeta-functions of holomorphic normalized Hecke-eigen cusp forms near the critical line.  相似文献   
73.
A nonlinear multiobjective optimization problem is considered. Two methods are proposed to generate solutions with an approximately uniform distribution in a Pareto set. The first method is supposed to find the solutions as minimizers of weighted sums of objective functions where the weights are properly selected using a branch and bound type algorithm. The second method is based on lexicographic goal programming. The proposed methods are compared with several metaheuristic methods using two and three-criteria tests and applied problems.  相似文献   
74.
A well-recognized one-dimensional global optimization method is generalized to the multidimensional case. The generalization is based on a multidimensional statistical model of multimodal functions constructed by generalizing computationally favorable properties of a popular one-dimensional model—the Wiener process. A simplicial partition of a feasible region is essential for the construction of the model. The basic idea of the proposed method is to search where improvements of the objective function are most probable; a probability of improvement is evaluated with respect to the statistical model. Some results of computational experiments are presented.  相似文献   
75.
This paper summarizes the results of axiomatic constructing statistical models of complicated multimodal functions. It is shown that an optimization algorithm may be constructed on the basis of a statistical model and some ideas of the rational choice theory. A brief review of related algorithms and reports on investigations of their efficiency is given.  相似文献   
76.
77.
A model of a complicated function under uncertainty is constructed axiomatically, formalizing suppositions on rationality of information on a considered function.  相似文献   
78.
Transformations of α-chloro- and α-bromobicyclo[3.3.1]nonanones under conditions of the Favorskii reaction were studied. The interaction of dihalodiketones with MeONa gives 2-oxatricyclo[4.3.1.03.8]decane (oxaprotoadamantane) derivatives as a result of intramolecular cyclization, whereas 3-bromobicyclononanone undergoes only nucleophilic substitution of bromine. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 342–344, February, 1997.  相似文献   
79.
A limit theorem in the sense of the weak convergence of probability measures in the space of meromorphic functions for the Estermann zeta-function is obtained. Partially supported by Lithuanian Foundation of Studies and Science  相似文献   
80.
We obtain a limit theorem in the sense of weak convergence of probability measures in the space of analytic functions for the Lerch zeta-function with algebraic irrational parameter. Partially supported by the Lithuanian Studies and Science Foundation.  相似文献   
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