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881.
J. J. EGOZCUE J. L. DIAZ-BARRERO V. PAWLOWSKY-GLAHN 《数学学报(英文版)》2006,22(4):1175-1182
The set of probability functions is a convex subset of L1 and it does not have a linear space structure when using ordinary sum and multiplication by real constants. Moreover, difficulties arise when dealing with distances between densities. The crucial point is that usual distances are not invariant under relevant transformations of densities. To overcome these limitations, Aitchison's ideas on compositional data analysis are used, generalizing perturbation and power transformation, as well as the Aitchison inner product, to operations on probability density functions with support on a finite interval. With these operations at hand, it is shown that the set of bounded probability density functions on finite intervals is a pre-Hilbert space. A Hilbert space of densities, whose logarithm is square-integrable, is obtained as the natural completion of the pre-Hilbert space. 相似文献
882.
883.
O.G. Kosareva N.A. Panov N. Akozbek V.P. Kandidov Q. Luo S.A. Hosseini W. Liu J.-F. Gravel G. Roy S.L. Chin 《Applied physics. B, Lasers and optics》2006,82(1):111-122
We demonstrate a three orders of magnitude increase and stability in the backscattered fluorescence signal from nitrogen molecules
by terawatt femtosecond laser pulse induced air filaments using a new method. The method is based on squeezing the initial
beam diameter using a telescope. The effect of laser shot-to-shot fluctuations was included in numerical simulations by a
random distribution of the initial intensity in both squeezed and non-squeezed beams. Statistical processing of the simulation
results shows that the average diameter of plasma channels as well as the total amount of free electrons generated in a bunch
of multiple filaments in air is larger in the squeezed beam. Shot-to-shot stability of the simulated plasma density increases
in the squeezed beam. The change of this plasma density with propagation distance is in good qualitative agreement with the
change of the range-corrected nitrogen fluorescence signal with distance.
PACS 42.65.Jx; 42.60.Jf; 42.68.Ay; 42.68.Wt 相似文献
884.
A. V. Kopylov I. V. Orekhov V. V. Petukhov A. E. Solomatin 《Physics of Atomic Nuclei》2006,69(11):1829-1832
Experiments sensitive to pp neutrinos from the Sun are very promising for precise measurement of the mixing angle ϑ
12. A νe
− scattering experiment (XMASS) and/or a charged-current experiment (indium detector) can measure the flux of electron pp neutrinos. One can find the total flux of pp neutrinos from a luminosity constraint after the contributions of 7Be and CNO neutrinos to the total luminosity of the Sun are measured. A radiochemical experiment utilizing a lithium target
has high sensitivity to the CNO neutrinos; thus, it has a good promise for precise measurement of the mixing angle and for
a test of the current theory of evolution of the stars.
The text was submitted by the authors in English. 相似文献
885.
V. S. Bilanych I. I. Makauz T. D. Mel’nichenko I. M. Rizak V. M. Rizak 《Physics of the Solid State》2006,48(11):2060-2064
The internal friction in Ge x As40 ? x S60 glasses is investigated in the temperature range 100 K-T g at infralow frequencies (10?3?10?1 Hz). It is shown that the concentration dependence of the internal friction of these materials changes as a result of the transformation of the dominant kinetic unit in dissipative processes of the relaxation and nonrelaxation types. It is established tha the change in the mechanism of internal friction in the Ge x As40 ? x S60 glasses leads to a jump in the activation energy of the α relaxation and to a local minimum in the frequency factor τ0. 相似文献
886.
P. V. Dvornikov 《Russian Physics Journal》2006,49(4):392-401
A standard model Lagrangian is constructed making the pseudo-Finsleroid generalization of the Yang-Mills field equation by
the conformal method. The Higgs field potential is suggested that ensures generation of particle masses caused by the spontaneous
symmetry breaking. After transition to the conformal coordinates, the expressions obtained assume the standard form that in
many cases allows the results of pseudo-Euclidean theory to be used in calculations of the Feynman diagrams.
__________
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 4, pp. 44–51, April, 2006. 相似文献
887.
888.
M. R. Darafsheh N. S. Karamzadeh A. R. Moghaddamfar 《Journal of Applied Mathematics and Computing》2006,21(1-2):437-450
IfG is a finite group, we define its prime graph Г(G), as follows: its vertices are the primes dividing the order ofG and two verticesp, q are joined by an edge, if there is an element inG of orderpq. We denote the set of all the connected components of the graph Г(G) by T(G)= {πi(G), fori = 1,2, …,t(G)}, where t(G) is the number of connected components of Г(G). We also denote by π(n) the set of all primes dividingn, wheren is a natural number. Then ¦G¦ can be expressed as a product of m1, m2, …, mt(G), where mi’s are positive integers with π(mi) = πi. Thesem i ’s are called the order components ofG. LetOC(G) := {m 1,m 2, …,m t (G)} be the set of order components ofG. In this paper we prove that, if G is a finite group andOC(G) =OC(M), where M is a finite simple group witht(M) ≥ 2, thenG is neither Frobenius nor 2-Frobenius. 相似文献
889.
890.
Electron beam processing of poly(ethylene terephthalate) (PET) films is found to promote significant changes in the melting heat, intrinsic viscosity and polymer film-liquid (water, isooctane and toluene) boundary surface tension. These properties are featured with several maximums depending on the absorbed dose and correlating with the modification of PET surface functionality. Studies using adsorption of acid-base indicators and IR-spectroscopy revealed that the increase of PET surface hydrophilicity is determined by the oxidation of methylene and methyne groups. Electron beam treatment of PET films on the surface of N-vinylpyrrolidone aqueous solution provided graft copolymerization with this comonomer at optimum process parameters (energy 700 keV, current 1 mA, absorbed dose 50 kGy). 相似文献