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11.
Július Korbaš 《Acta Mathematica Hungarica》2004,105(1-2):129-137
We prove new results about the vector field problem on the real flag manifolds O(n)/O(1) x O(1) x O(n - 2). For some infinite families of these manifolds, we completely solve the vector field problem. 相似文献
12.
Given disjoint setsP
1,P
2, ...,P
d
inR
d
withn points in total, ahamsandwich cut is a hyperplane that simultaneously bisects theP
i
. We present algorithms for finding ham-sandwich cuts in every dimensiond>1. Whend=2, the algorithm is optimal, having complexityO(n). For dimensiond>2, the bound on the running time is proportional to the worst-case time needed for constructing a level in an arrangement
ofn hyperplanes in dimensiond−1. This, in turn, is related to the number ofk-sets inR
d−1
. With the current estimates, we get complexity close toO(n
3/2
) ford=3, roughlyO(n
8/3
) ford=4, andO(n
d−1−a(d)
) for somea(d)>0 (going to zero asd increases) for largerd. We also give a linear-time algorithm for ham-sandwich cuts inR
3 when the three sets are suitably separated.
A preliminary version of the results of this paper appeared in [16] and [17]. Part of this research by J. Matoušek was done
while he was visiting the School of Mathematics, Georgia Institute of Technology, Atlanta, and part of his work on this paper
was supported by a Humboldt Research Fellowship. W. Steiger expresses gratitude to the NSF DIMACS Center at Rutgers, and his
research was supported in part by NSF Grants CCR-8902522 and CCR-9111491. 相似文献
13.
14.
The partition coefficient of strontium upon its extraction from the aqueous solutions of picric acid into chloroform containing DC-18-crown-6, B-15-crown-5 after their exposition to gamma radiation has been studied. A significant decrease of the partition coefficient in the studied range of doses 10–70 kGy was observed. This effect can be attributed to the radiolytic products of chloroform. The radiation destruction as well as dehydrogenation of crown ethers were not observed. 相似文献
15.
K. Prokeš 《Czechoslovak Journal of Physics》2002,52(2):253-258
Many materials exhibit various magnetic phenomena as a function of magnetic field, temperature and/or pressure. Usually, bulk magnetic measurements provide first information on the magnetic state of the material by measuring their response on the applied magnetic field. However, it is necessary to investigate materials also on a microscopic scale. This is often done by means of neutron scattering. In this contribution we discuss basic ideas of this method and we report on few experimental results obtained with a split-pair coil 14.5 T superconducting magnet which can be combined with dilution stick offering temperatures as low as 30 mK and/or with a small clamped-type pressure cell which offers pressure up to 1.0 GPa. 相似文献
16.
The validity of local parton-hadron duality within the framework of HERWIG and JETSET event generators is investigated. We concentrate one
+
e
– annihilations in LEP 2 energy range as these interactions provide theoretically the cleanest condition for the discussion of this concept. We conclude that the concept of local parton-hadron duality is not valid in either of the two generators considered. 相似文献
17.
18.
Š. Jakševičius 《Lithuanian Mathematical Journal》1992,32(2):174-180
Kaunas Academy of Agriculture, 4324 Noreikiškés, Lithuania. Translated from Lietuvos Matematikos Rinkinys, Vol. 32, No. 2,
pp. 221–228, April–June, 1992. 相似文献
19.
František Toman Ludvík Beneš 《Journal of inclusion phenomena and macrocyclic chemistry》2007,59(3-4):231-236
Differential molar adsorption enthalpies (DMAE) were determined by gas chromatographic measurements of specific retention
volume of vapors on the surface of two forms of Mg–Al hydrotalcite. A linear dependence of the DMAE on the number of the carbon
atoms in hydrocarbons was observed for both form of hydrotalcite. The dependence of the differential molar adsorption enthalpies
on the number of chlorine atoms in organic molecules is discussed. A linear dependence of DMAE on the molecular weight of
chloroderivatives of methane and ethylene on the basic form in an order monochloromethane < dichloromethane < trichloromethane
or vinylidene chloride < 1,1-dichloroethylene < trichloroethylene was found. 相似文献
20.
The paper is devoted to the research of large deviation probabilities in the approximation by compound Poisson law. 相似文献