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排序方式: 共有1115条查询结果,搜索用时 31 毫秒
1.
Ortiz Adolfo Yang Jianhua Coccolo Mattia Seoane Jesús M. Sanjuán Miguel A. F. 《Nonlinear dynamics》2020,102(4):2323-2337
Nonlinear Dynamics - The main purpose of this paper is to study both the underdamped and the overdamped dynamics of the nonlinear Helmholtz oscillator with a fractional-order damping. For that... 相似文献
2.
When an organization solves a portfolio problem with public projects evaluated by multiple criteria, in which the economic dimension is not essential or not well characterized, the classical methods are not useful. We propose a non-linear preference model developed from normative Value Theory and using fuzzy sets to model some sources of imprecision. This model can be considered as a generalization of the classical approaches. However, the optimization problem is very complex in order to be solved with non-linear programming techniques. Therefore, the model is exploited by an evolutionary algorithm, able to achieve a strong improvement of the quality of solution. 相似文献
3.
The problem of finding the Euclidean distance between two convex polyhedra can be reduced to the combinatorial optimization problem of finding the minimum distance between their faces. This paper presents a global optimality criterion for this problem. An algorithm (QLDPA) for the fast computation of the distance between convex and bounded polyhedra is proposed as an application of it. Computer experiments show its fast performance, especially when the total number of vertices is large. 相似文献
4.
E. Casarejos P. Armbruster L. Audouin J. Benlliure M. Bernas A. Boudard R. Legrain S. Leray B. Mustapha S. Czajkowski T. Enqvist B. Fernandez J. Pereira M. Pravikoff F. Rejmund K. -H. Schmidt C. Stephan J. Taieb L. Tassan-Got C. Villagrasa C. Volant W. Wlazlo 《Physics of Atomic Nuclei》2003,66(8):1413-1420
The isotopic production cross sections of heavy residues in relativistic heavy-ion collisions have been investigated in inverse kinematics. The primary reaction products were fully identified in mass and atomic number prior to beta decay using the fragment separator FRS. The huge collection of data obtained helps in the understanding of the two main reaction mechanisms involved: fragmentation and fission. These data provide basic information for future radioactive ion beam facilities and for technical applications like intense neutron sources by means of spallation targets. 相似文献
5.
Novel oscillatory flow results of phenoxy/organoclay nanocomposites are analysed considering the blocking effect of nanostructure on polymer chain mobility. The modification provoked by this hindering effect on loss tangent spectrum is investigated. The study of three different systems, involving a pristine montmorillonite and two montmorillonites modified with one alkyl tail and two alkyl tails, respectively, leads to conclude that polymer-alkyl repulsive interactions play the most important role in the chain mobility obstruction process. Our results suggest that polymer-alkyl interactions increase with temperature. 相似文献
6.
Wagner SR Hinshaw DA Ong RA Snyder A Abrams G Adolphsen CE Akerlof C Alexander JP Alvarez M Amidei D Baden AR Ballam J Barish BC Barklow T Barnett BA Bartelt J Blockus D Bonvicini G Boyarski A Boyer J Brabson B Breakstone A Brom JM Bulos F Burchat PR Burke DL Butler F Calvino F Cence RJ Chapman J Cords D Coupal DP DeStaebler HC Dorfan DE Dorfan JM Drell PS Feldman GJ Fernandez E Field RC Ford WT Fordham C Frey R Fujino D Gan KK Gidal G Gladney L Glanzman T Gold MS Goldhaber G Green A 《Physical review letters》1990,64(10):1095-1098
7.
Weir AJ Klein SR Abrams G Adolphsen CE Akerlof C Alexander JP Alvarez M Amidei D Baden AR Ballam J Barish BC Barklow T Barnett BA Bartelt J Blockus D Bonvicini G Boyarski A Boyer J Brabson B Breakstone A Brom JM Bulos F Burchat PR Burke DL Butler F Calvino F Cence RJ Chapman J Cords D Coupal DP DeStaebler HC Dorfan DE Dorfan JM Drell PS Feldman GJ Fernandez E Field RC Ford WT Fordham C Frey R Fujino D Gan KK Gidal G Gladney L Glanzman T Gold MS Goldhaber G Green A Grosse-Wiesmann P Haggerty J 《Physical review D: Particles and fields》1990,41(5):1384-1388
8.
Adolfo M. Nemirovsky Maurício D. Coutinho-Filho 《Journal of statistical physics》1988,53(5-6):1139-1153
A field-theoretic representation is presented to count the number of configurations of a single self-avoiding walk on a hypercubic lattice ind dimensions with periodic boundary conditions. We evaluate the connectivity constant as a function of the fractionf of sites occupied by the polymer chain. The meanfield approximation is exact in the limit of infinite dimensions, and corrections to it in powers ofd
–1 can be systematically evaluated. The connectivity constant and the site entropy calculated throughout second order compare well with known results in two and three dimensions. We also find that the entropy per site develops a maximum atf1–(2d)–1. Ford=2 (d=3), this maximum occurs atf~0.80 (f~0.86) and its value is about 50% (30%) higher than the entropy per site of a Hamiltonian walk (f=1). 相似文献
9.
J. Fernandez M.I. Paz Andrade F. Sarmiento R. Bravo 《The Journal of chemical thermodynamics》1983,15(12):1145-1149
The excess molar enthalpies HmE of methyl propanoate or methyl pentanoate + 1-butanol, + 1-hexanol, + 1-octanol, and + 1-decanol have been determined experimentally at 298.15 K using a Calvet microcalorimeter. For all these mixtures HmE > 0; the values increase with the chain length of the alkanol but decrease as the ester chain lengthens. 相似文献
10.
N. S. Nesterenko F. Thibault-Starzyk V. Montouilliout V. V. Yushchenko C. Fernandez J.-P. Gilson F. Fajula I. I. Ivanova 《Kinetics and Catalysis》2006,47(1):40-48
A new approach to the evaluation of the accessibility of acid sites in microporous/mesoporous materials is developed and tested
using a series of dealuminated mordenites. This approach is based on an IR-spectroscopic study of the consecutive adsorption
of substituted alkylpyridines (pyridine, 2,4,6-trimethylpyridine, and 2,4,6-triethylpyridine) and carbon monoxide. This method
allowed us to determine the strength and number of acid sites with various degrees of accessibility. The adsorption of 2,4,6-triethylpyridine
on various types of materials is studied. The extinction coefficients of alkylpyridines are determined using a McBain balance
placed in a cell for IR-spectroscopic measurements.
Original Russian Text N.S. Nesterenko, F. Thibault-Starzyk, V. Montouilliout, V.V. Yushchenko, C. Fernandez, J.-P. Gilson,
F. Fajula, I.I. Ivanova, 2006, published in Kinetika i Kataliz, 2006, Vol. 47, No. 1, pp. 45–53. 相似文献