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1.
2.
Jean-Pierre Aubin 《Journal of Evolution Equations》2012,12(1):99-117
We assume that the evolution of the population is governed by a controlled McKendrick age-structured partial differential
equation where the mortality rate and immigrated population levels are no longer known coefficients, but contingent regulation
parameters chosen for a given purpose, for instance, for requiring that the population satisfies prescribed viability constraints
depending on time and age. The Lotka renewal equation relating the boundary condition (number of births) to the integral with
respect to age of the population is replaced by the introduction of another regulation parameter in the boundary condition,
regarded as a natality policy. We may control it by its derivative, regarded as a natality decision. We then construct a regulation map, associating with the population level, the time and the age the subset of natality policies,
a mortality rates and an immigration levels needed for governing viable evolutions of the population. 相似文献
3.
The ionized-impurity mobility of Cd3As2 at 4.2 K with carrier concentration lying in the range 1018–1019 cm?3 has been calculated taking into account the inverted HgTe-type energy band structure of this material. A comparison of the results with experimental mobility data leads to a static dielectric constant of ?0 = 36. This value represents a lower limit since any compensation effects would increase the fitted estimate of ?0. 相似文献
4.
Jean-Louis Tassoul Gilles Aubin 《Journal of Mathematical Analysis and Applications》1974,45(1):116-126
This paper deals with finite-amplitude axisymmetric disturbances in a self-gravitating fluid column of finite radius R. It is shown that the cutoff wavelength λnl above which gravitational breakup occurs now depends on the relative amplitude of the initial perturbation. Actually, for small-but finite-amplitude disturbances, , where λl ( = 5.8898R) designates the cutoff wavelength predicted in the linear approximation. 相似文献
5.
Behnia K Bel R Kasahara Y Nakajima Y Jin H Aubin H Izawa K Matsuda Y Flouquet J Haga Y Onuki Y Lejay P 《Physical review letters》2005,94(15):156405
We present a study of thermal conductivity in the normal state of the heavy-fermion superconductor URu2Si2. Ordering at 18 K leads to a steep increase in thermal conductivity and (in contrast with all other cases of magnetic ordering in heavy-fermion compounds) to an enhancement of the Lorenz number. By linking this observation to several other previously reported features, we conclude that most of the carriers disappear in the ordered state and this leads to a drastic increase in both the phononic and electronic mean free path. 相似文献
6.
Aubin C Bernard C Detar C Di Pierro M Freeland ED Gottlieb S Heller UM Hetrick JE El-Khadra AX Kronfeld AS Levkova L Mackenzie PB Menscher D Maresca F Nobes M Okamoto M Renner D Simone J Sugar R Toussaint D Trottier HD;Fermilab Lattice Collaboration;MILC Collaboration;HPQCD Collaboration 《Physical review letters》2005,95(12):122002
We present the first lattice QCD calculation with realistic sea quark content of the D+-meson decay constant f(D+). We use the MILC Collaboration's publicly available ensembles of lattice gauge fields, which have a quark sea with two flavors (up and down) much lighter than a third (strange). We obtain f(D+)=201+/-3+/-17 MeV, where the errors are statistical and a combination of systematic errors. We also obtain f(Ds)=249+/-3+/-16 MeV for the Ds meson. 相似文献
7.
Short peptides derived from p14ARF and Hdm2 (14 and 15 amino acids in length, respectively), two cancer associated proteins, have been found to co-assemble into amyloid-like structures. Larger protein domains containing these peptide segments interact in cells and also undergo a disorder-to-order transition upon binding in vitro. In contrast to the association of beta-strand assemblies with amyloid diseases, the system described herein utilizes the formation of binary, extended beta-strands as a novel mechanism of biomolecular assembly. The beta-strand-containing fibrils formed from these peptides may allow the directed assembly of decorated fibrils with applications as biological nanostructures. 相似文献
8.
The aim of this paper is to combine two ways for representing uncertainty through stochastic differential inclusions: a 'stochastic uncertainty", driven by a Wiener process, and a 'contingent uncertainty", driven by a set-valued map. The paper is also devoted to the invariance of closed under stochastic differential inclusions with a Lipschitz right-hand side, characterized in terms of stochastic tangent sets to closed subsets. 相似文献
9.
Volume Contents
Contents to Volume 8 相似文献10.
Lengagne T Aubin T Jouventin P Lauga J 《The Journal of the Acoustical Society of America》2000,107(1):508-516
In the king penguin, Aptenodytes patagonicus, incubation and brooding duties are undertaken alternately by both partners of a pair. Birds returning from foraging at sea find their mate in the crowded colony using acoustic signals. Acoustic recognition of the mate maintains and strengthens the mate's fidelity and favors synchronization in the different stages of reproduction. In this study it was found that the king penguin vocalizes in response to the mate's playback calls, but not to those of neighbors or unfamiliar conspecific individuals. To study individual features used by the birds for individual recognition of mates, various experimental signals consisting of synthesized modifications of the mate' s call were played back to the incubating bird. Results indicated that birds attend to the FM profile of the call, in particular its initial inflexion. The frequency modulation shape of the syllable can be assimilated to a vocal signature repeated though the different syllables of the call. King penguins pay little attention to the call' s AM envelope or its absolute frequency. 相似文献