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991.
Alexandre Goldsztejn Ferenc Domes Brice Chevalier 《Journal of Global Optimization》2014,58(4):653-672
Three rejection tests for multi-objective optimization problems based on first order optimality conditions are proposed. These tests can certify that a box does not contain any local minimizer, and thus it can be excluded from the search process. They generalize previously proposed rejection tests in several regards: Their scope include inequality and equality constrained smooth or nonsmooth multiple objective problems. Reported experiments show that they allow quite efficiently removing the cluster effect in mono-objective and multi-objective problems, which is one of the key issues in continuous global deterministic optimization. 相似文献
992.
Alexandre F. Benchimol J.L. Dangla J. Dubon-Chevallier C. Amarger V. 《Electronics letters》1990,26(21):1753-1755
The first demonstration of a GaInP/GaAs heterojunction bipolar transistor grown by chemical beam epitaxy is reported. A common-emitter current gain of 30 at a current density of 110 A/cm/sup 2/ is obtained for a beryllium base doping as high as 8*10/sup 19/ cm/sup -3/. The base sheet resistance of 140 Omega / Square Operator is among the lowest reported values.<> 相似文献
993.
Elisa M. P. Ciapina Walber C. Melo Lidia M. M. Santa Anna Alexandre S. Santos Denise M. G. Freire Nei Pereira Jr. 《Applied biochemistry and biotechnology》1996,131(1-3):880-886
The production of biosurfactant by Rhodococcus erythropolis during the growth on glycerol was investigated. The process was carried out at 28°C in a 1.5-L bioreactor using glycerol
as carbon source. The bioprocess was monitored through measurements of biosurfactant concentration and glycerol consumption.
After 51 h of cultivation, 1.7 g/L of biosurfactant, surface, and interfacial tensions values (with n-hexadecane) of 43 and 15 mN/m, respectively, 67% of Emulsifying Index (E
24), and 94% of oil removal were obtained. The use of glycerol rather than what happens with hydrophobic carbon source allowed
the release of the biosurfactant, originally associated to the cell wall. 相似文献
994.
995.
Transport in Porous Media - 相似文献
996.
Fernando Loup Paulo Alexandre Santos Dorabella Martins da Silva Santos 《General Relativity and Gravitation》2003,35(11):2035-2044
It is shown that the ansatz of Chung-Freese models a new braneworld, and while superluminal, this braneworld does not suffer from the pathologies of other FTL methods. It is also shown that our universe is a trapped surface inside a universe with large extra dimensions, and in order to preserve compatibility with the Standard Model (SM), we present two trapping mechanisms that keeps SM fields inside our brane. For the Chung-Freese braneworld we develop a similar formalism to Morris domain walls, and we present our universe as a low level state in a potential well with the bulk in the highest levels of potential. Finally, we show that the Israel condition can also act as a trapping mechanism for SM fields inside the brane. Our model uses the idea that fermions are allowed to escape to the bulk inspired by the work of Havoudiasl-Hewett-Rizzo [2]. 相似文献
997.
Alexandre Froda 《Mathematische Zeitschrift》1965,89(2):126-136
Sans résumé 相似文献
998.
Insertion poly(methyl acrylate) and poly(methyl methacrylate) were prepared from monomers adsorbed in monolayers on the surface of montmorillonite clay, both in the presence and in the absence of bifunctional crosslinkers (ethylene glycol dimethacrylate and tetramethylene glycol dimethacrylate). The insertion poly(methyl acrylate) and the crosslinked insertion poly(methyl methacrylate) and dilute-solution properties quite different from conventional polymers of these monomers, the differences including high light-scattering molecular weights combined with low viscosities, low values of the second virial coefficient, unusually large variations of the Huggins' constant k′ with the time-temperature history of the solutions, and low sedimentation velocities. These properties suggest that the insertion polymers have compact structures and are consistent with the postulate of sheetlike macromolecules. The dilute-solution properties of insertion poly(methyl methacrylate) made without crosslinker, unlike those of similarly prepared poly(methyl acrylate), were similar to those of conventional poly(methyl methacrylate). This difference in behavior is attributed to the different tendencies of the two monomers to undergo branching or crosslinking during radical polymerization. 相似文献
999.
Alexandre J. Chorin 《Journal of statistical physics》1994,76(3-4):835-856
A phase diagram is mapped out for a 21/2-dimensional vortex lattice model in which vortex filaments lie in a plane, while both the velocity field and the Green function are three-dimensional. Both positive and negative temperatures are considered. Various qualitative properties of turbulent states and of the super-fluid transition are well verified within the limitations of the model; the percolation properties of vortex transitions are exhibited; the differences between superfluid and classical vortex motion are highlighted, as is the importance of topological constraints in vortex dynamics; an earlier model of intermittency is verified. 相似文献
1000.
Alexandre I. Danilenko Valentin Ya. Golodets 《Transactions of the American Mathematical Society》1996,348(12):4857-4882
Let be an ergodic automorphism of a Lebesgue space and a cocycle of with values in an Abelian locally compact group . An automorphism from the normalizer of the full group is said to be compatible with if there is a measurable function such that at a.e. . The topology on the set of all automorphisms compatible with is introduced in such a way that becomes a Polish group. A complete system of invariants for the -outer conjugacy (i.e. the conjugacy in the quotient group is found. Structure of the cocycles compatible with every element of is described.