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761.
James P. Henderson 《Topology and its Applications》1981,12(3):267-282
A compact subset X of a polyhedron P is cellular in P if there is a pseudoisotropy of P shrinking precisely X to a point. A proper surjection between polyhedra f:P→Q is cellular if each point inverse of f is cellular in P. It is shown that if f:P→Q is a cellular map and either P or Q is a generalized n-manifold, n≠4, then f is approximable by homeomorphisms. Also, if P or Q is an n-manifold with boundary, n≠4, 5, then a cellular map f:P→Q is approximable by homeomorphisms. A cellularity criterion for a special class of cell-like sets in polyhedra is established. 相似文献
762.
763.
Igor Kříž 《Combinatorica》1984,4(4):317-319
Forn≧6 there exists a graphG with dimG=n, dimG*≧n+2, whereG* isG with a certain edge added. 相似文献
764.
765.
Kiyokatsu Jinno 《Journal of separation science》1984,7(2):66-67
The possibility of high-speed micro-HPLC has been investigated using a short micro-column (35 mm × 0.5 mm i.d.) packed with 3 μm ODS particle. The results indicate that this approach has considerable potential for good separations with short analysis time. A typical example shows only three minutes is required with a plate count of 3,800 to separate seven PAHs. 相似文献
766.
Pranab Kumar Sen 《Statistics & probability letters》1984,2(4):193-196
For testing the hypothesis that two (symmetric) distributions may differ only in locations, a Kolmogorov-Smirnov type test based on the aligned observations is considered and its properties are studied. 相似文献
767.
768.
Wolfgang Hackbusch 《Numerische Mathematik》1977,28(2):121-142
Summary The procedurediwiex presented in this paper provides an approximate solution to Cauchy's initial value problem for general hyperbolic systems of first order. The procedurecharex can be applied to the initial value problem for a hyperbolic system of quasi-linear differential equations. This second method is a kind of method of characteristics. It produces a solution for the whole domain of determinancy. Both procedures use extrapolation to the limit.
Editor's Note. In this fascile, prepublication of algorithms from the Approximations series of the Handbook for Automatic Computation is continued. Algorithms are published in ALGOL 60 reference language as approved by the IFIP. Contributions in this series should be styled after the most recently published ones 相似文献
769.
A necessary and sufficient condition is given for the existence of stationary probability distributions of a non-Markovian model with linear transition rule. Similar to the Markovian case, stationary probability distributions are characterized as eigenvectors of nonnegative matrices. The model studied includes as special cases the Markovian model as well as the linear learning model and has applications in psychological and biological research, in control theory, and in adaption theory. 相似文献
770.
Using the concepts of conditional expectation and independence of subalgebras, we characterize those contractive projections, P, on Lp, over a probability measure space, having the property that I − P is contractive. By contractive projection we mean a linear operator, P, on the Lebesgue space, Lp, 1 < p < ∞, ≠2, with P2 = P, ∥ = 1. 相似文献