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991.
Hiroshi Shibata 《Physica A》1998,260(3-4)
Disorderness of spatiotemporal patterns which are obtained by nonlinear partial differential equations is characterized quantitatively. The mean Lyapunov exponent for a nonlinear partial differential equation is given. The local Lyapunov exponent which is a finite time average of the mean Lyapunov exponent is shown to have close relation to the spatiotemporal patterns. It is suggested that the systems which are described by nonlinear partial differential equations are characterized statistically through the probability distribution function of the local Lyapunov exponent. 相似文献
992.
R. Seki D. Arai Y. Nagashima T. Imanaka T. Takahashi T. Matsuhiro 《Journal of Radioanalytical and Nuclear Chemistry》2003,255(2):245-247
Long-lived chlorine, 36Cl (T1/2 = 301,000 y) in environmental samples has been measured by the AMS system installed in Tandem Accelerator Center, University of Tsukuba. A tri-carbon-molecular 12C3
- pilot beam method is used to stabilize the terminal voltage of the tandem. A small amount of pure carbon graphite is well mixed into a AgCl target material for creating Cl- and 12C3
- in the ion source. A 36S isobaric interference in the system is eliminated to determine 36Cl in environmental samples by chemical procedure. Some samples containing chlorine such as soil, chemical reagents and table salt have been collected in the JCO criticality accident site and analyzed to detect neutron-induced 36Cl. The experimental result has been compared with a theoretical calculation. 相似文献
993.
Hiroshi Zuzuki 《Graphs and Combinatorics》1994,10(1):61-65
We apply a circuit chasing technique to distance-biregular graphs of girth divisible by four to derive a parameter restriction. As an application, we give a classification of distance-biregular graphs of girth divisible by four with trivalent vertices. 相似文献
994.
995.
We study the spectral properties of a chiral random banded matrix (chRBM) with elements decaying as a power-law Hij|i−j|−. This model is equivalent to a chiral 1D Anderson Hamiltonian with long range power-law hopping. In the weak disorder limit we obtain explicit nonperturbative analytical results for the density of states (DoS) and the two-level correlation function (TLCF) by mapping the chRBM onto a nonlinear σ model. We also put forward, by exploiting the relation between the chRBM at =1 and a generalized chiral random matrix model, an exact expression for the above correlation functions. We give compelling analytical and numerical evidence that for this value the chRBM reproduces all the features of an Anderson transition. Finally we discuss possible applications of our results to quantum chromodynamics (QCD). 相似文献
996.
be a network, where is an undirected graph with nodes and edges, is a set of specified nodes of , called terminals, and each edge of has a nonnegative integer capacity . If the total capacity of edges with one end at is even for every non-terminal node , then is called inner Eulerian. A free multiflow is a collection of flows between arbitrary pairs of terminals such that the total flow through each edge
does not exceed its capacity.
In this paper we first generalize a method in Karzanov [11] to find a maximum integer free multiflow in an inner Eulerian network, in time, where is the complexity of finding a maximum flow between two terminals. Next we extend our algorithm to solve the so-called laminar locking problem on multiflows, also in time.
We then consider analogs of the above problems in inner balanced directed networks, which means that for each non-terminal node , the sums of capacities of arcs entering and leaving are the same. We show that for such a network a maximum integer free multiflow can be constructed in time, and then extend this result to the corresponding locking problem.
Received: March 24, 1997 相似文献
997.
998.
In this paper, we present an efficient implementation of theO(mn + n
2 logn) time algorithm originally proposed by Nagamochi and Ibaraki (1992) for computing the minimum capacity cut of an undirected network. To enhance computation, various ideas are added so that it can contract as many edges as possible in each iteration. To evaluate the performance of the resulting implementation, we conducted extensive computational experiments, and compared the results with that of Padberg and Rinaldi's algorithm (1990), which is currently known as one of the practically fastest programs for this problem. The results indicate that our program is considerably faster than Padberg and Rinaldi's program, and its running time is not significantly affected by the types of the networks being solved.Corresponding author. 相似文献
999.
Takako Yamaguchi Kohei Hasegawa Shinichiro Kamino Kanako Miyachi Hiroshi Tominaga Yoshikazu Fujita 《Analytical sciences》2007,23(2):223-226
A simple and highly sensitive spectrophotometric method for the determination of uric acid (UA) was established based on fading of the o-hydroxyhydroquinonephthalein-palladium(II)-hexadecyltrimethylammonium complex. In the determination of UA, Beer's law is obeyed in the range of 0.01-0.20 microg ml(-1), with an effective molar absorptivity at 635 nm, the relative standard deviation being 6.5 x 10(5) dm(3) mol(-1) cm(-1) and 1.5% (n = 5). This method is about 20-times more sensitive than the conventional methods. The method was successfully applied to the assay of UA in human urine. 相似文献
1000.
Anthony To-Ming Lau Hiromichi Miyake Wataru Takahashi 《Nonlinear Analysis: Theory, Methods & Applications》2007
The purpose of this paper is to study iterative schemes of Browder and Halpern types for a semigroup of nonexpansive mappings on a compact convex subset of a smooth (and strictly convex) Banach space with respect to a sequence of strongly asymptotic invariant means defined on an appropriate space of bounded real valued functions of the semigroup. Various applications to the additive semigroup of nonnegative real numbers and commuting pairs of nonexpansive mappings are also presented. 相似文献