The paper presents a general approach to the evaluation of the complexity of classes of algorithms, so-called pVCD-method. To develop this method, all the examined families of models of empiric generalization were restricted to classes
implementable on computers and, wider, by examining their partially recursive representations. Within the framework of the
algorithmic approach, the concept of Kolmogorov’ complexity of algorithms for the recognition of properties or the extraction
of regularities is proposed. The method proposed to evaluate the nonrandomness of the extraction of empirical regularities
is based on this concept. 相似文献
Computer-aided analysis of autoradiographic films of DNA fragments is presented. The Powell least-squares procedure is used for optimization of parameters for components of complex densitometric curves. Since each densitometric spectrum may be divided for several non-overlapped blocks of bands, there is no upper limit on the number of parameters which must be optimized. Eight shapes for the component bands are utilized: symmetric and asymmetric Gauss and Cauchy functions, direct, symmetric and asymmetric product of Gauss function and inverse of Cauchy function, and log-normal function. The probability of DNA cleavage is calculated with correction for multiple cuts. The methods presented was applied to detailed analysis of densitometric spectra of a 21-bp DNA restriction fragment and allowed for direct correlation between structural microheterogeneity of DNA and the resulting cutting pattern. This method should facilitate the analysis of densitometric data from antibiotic-induced cleavage of DNA and footprinting experiments. 相似文献
In this paper, we study the semicycles of oscillatory solutions of the delay difference equation yn+1 − yn + pnyn-k = 0, where pn is a sequence of nonnegative real numbers and k is a positive integer. Upper bound of numbers of terms of semicycles are determined in the case when Our results improve and complement known results in literature. 相似文献
The problem to find a 4-edge-coloring of a 3-regular graph is solvable in polynomial time but an analogous problem for 3-edge-coloring is NP-hard. To make the gap more precise, we study complexity of approximation algorithms for invariants measuring how far is a 3-regular graph from having a 3-edge-coloring. We show that it is an NP-hard problem to approximate such invariants with an error O(n1−ε), where n denotes the order of the graph and 0<ε<1 is a constant. 相似文献
In spite of being a classical method for solving differential equations, the method of variation of parameters continues having a great interest in theoretical and practical applications, as in astrodynamics. In this paper we analyse this method providing some modifications and generalised theoretical results. Finally, we present an application to the determination of the ephemeris of an artificial satellite, showing the benefits of the method of variation of parameters for this kind of problems. 相似文献
