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101.
详实地阐述了运输部多年来坚持高效的群众性技术创新,在丰富的创新实践中凝练并提出了“问题就是管理资源”的全新理念,在这一理念的推动下,运输部坚持向问题要课题,向问题要成效,向问题要成果,并建立了以现实问题和前瞻性问题管理为核心,以“十大机制”、“四个系统”、“三个流程”为主线的技术创新模式。技术创新成了推动莱钢铁运发展和精细管理的活的灵魂。 相似文献
102.
V. M. Kravtsov 《Cybernetics and Systems Analysis》2007,43(1):25-33
It is proved that, for any r ∈ { 2n, 2n + 1,…, 3n−2} and only for such r, the polytope of a three-index axial assignment problem
of order n, n ≥ 2, contains completely r-noninteger vertices (r-CNVs), i.e., vertices such that all their positive components
are fractional and their number equals r. For each r ∈ {2n, 2n + 1,…, 3n −2}, all the types of r-CNVs are characterized and
the combinatorial properties of completely r-noninteger vertices of the polytope are studied.
__________
Translated from Kibernetika i Sistemnyi Analiz, No. 1, pp. 33–44, January–February 2007. 相似文献
103.
The concept of combinatorial objects is formalized. It allows strict definition of a combinatorial optimization problem (COP).
An efficient metaheuristic method to solve COPs (H-method) is considered. It includes stochastic local search algorithms as
a built-in procedure. A parallel implementation of the H-method is set forth and analyzed. The results from a numerical experiment
and solution of some well-known COPs on personal computers and on the SKIT cluster supercomputer are presented.
The study was supported by INTAS (Project 06-1000017-8909).
__________
Translated from Kibernetika i Sistemnyi Analiz, No. 6, pp. 70–79, November–December 2007. 相似文献
104.
The efficiency characteristics of multicast key distribution schemes based on (v, b, r, λ)-designs are investigated. The stability
and connectivity of such designs are estimated. These estimates generalize and enhance the well-known estimates for the efficiency
characteristics of multicast key distribution schemes based on incomplete block designs.
__________
Translated from Kibernetika i Sistemnyi Analiz, No. 3, pp. 100–111, May–June 2007. 相似文献
105.
A pseudohyperbolic problem of optimal control of intratumoral drug distribution is formulated. It takes into account the heterogeneity
of tumor tissues and effects of convection diffusion in a fissured porous medium. A mathematical model constructed and the
corresponding optimal control problem are shown to be correct.
__________
Translated from Kibernetika i Sistemnyi Analiz, No. 6, pp. 147–154, November–December 2007. 相似文献
106.
《中华人民共和国煤炭法》亟待修订 总被引:1,自引:0,他引:1
当前,由于《煤炭法》颁布的时代背景发生很大变化,该法已经不能适应形势发展和实际工作的需要。该法存在的主要问题包括煤炭开采市场准入门槛设置过低、对煤炭生产开发规划规定过分原则等。我们应以科学发展观为指导,按照市场经济规律的要求,针对存在的问题尽快对《煤炭法》进行修订和完善。 相似文献
107.
Uwe Schöning 《Information Processing Letters》2006,98(4):127-129
An N-superconcentrator is a directed, acyclic graph with N input nodes and N output nodes such that every subset of the inputs and every subset of the outputs of same cardinality can be connected by node-disjoint paths. It is known that linear-size and bounded-degree superconcentrators exist. Here it is proved that such superconcentrators exist (by a random construction of certain expander graphs as building blocks) having density 28 (where the density is the number of edges divided by N). The best known density before this paper was 34.2 [U. Schöning, Construction of expanders and superconcentrators using Kolmogorov complexity, J. Random Structures Algorithms 17 (2000) 64-77] or 33 [L.A. Bassalygo, Personal communication, 2004]. 相似文献
108.
109.
Alessandra Lumini 《Pattern recognition》2006,39(4):714-716
We present a system for fingerprint verification that approaches the problem as a two-class pattern recognition problem. The features extracted by “FingerCode” are used to capture the ridge strength. This feature vector is then classified as genuine or impostor according to a novel approach to handle the fingerprint verification as a two-class problem. Moreover, we show that extracting the features from sub-images around the core permits to better represent the local information. 相似文献
110.
Given a scalar, stationary, Markov process, this short communication presents a closed-form solution for the first-passage problem for a fixed threshold b. The derivation is based on binary processes and the general formula of Siegert [Siegert AJF. On the first-passage time probability problem. Physical Review 1951; 81:617–23]. The relation for the probability density function of the first-passage time is identical to the commonly used formula that was derived by VanMarcke [VanMarcke E. On the distribution of the first-passage time for normal stationary random processes. Journal of Applied Mechanics ASME 1975; 42:215–20] for Gaussian processes. The present derivation is based on more general conditions and reveals the criteria for the validity of the approximation. Properties of binary processes are also used to derive a hierarchy of upper bounds for any scalar process. 相似文献