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1.
B. Satco 《Journal of Mathematical Analysis and Applications》2007,332(2):919-933
Existence theorems and some properties of solutions set of three boundary value second order differential equations and inclusions in Banach spaces are obtained under Henstock, respectively Henstock-Kurzweil-Pettis integrability assumptions. Our results extend those obtained by Azzam, Castaing and Thibault in the Bochner integrability setting and in the Pettis integrability one. The continuity of the (unique) solution with respect to a parameter in the single-valued case is also studied. 相似文献
2.
Abstract This paper develops a bioeconomic forestry model that makes it possible to take ecosystem services that are independent of the age structure of trees into account. We derive the Faustmann–Hartman optimal harvesting strategy as a special case. The bioeconomic model is then extended to account for the fact that forest harvesting decisions impact on other ecological resources, which provide benefits for the wider community. The paper focuses on impacts associated with disturbance caused by logging operations and habitat destruction due to tree removal. This enables us to explore the interactions between forest management and the dynamics of ecological resources. The optimal rotation rule is obtained as a variation on the traditional Faustmann–Hartman equation, where an additional term captures the potential benefits derived from the growth of the ecological resource valued at its shadow price. The steady‐state solutions to the problem and sensitivity to model parameter are identified using numerical analysis. 相似文献
3.
Laurent Baratchart Monique Chyba Jean-Baptiste Pomet 《Journal of Dynamics and Differential Equations》2007,19(1):75-107
We consider the problem of locally linearizing a control system via topological transformations. According to [2,3], there is no naive generalization of the classical Grobman–Hartman theorem for ODEs to control systems: a generic control system, when viewed as a set of under-determined differential equations parametrized by the control, cannot be linearized using pointwise transformations on the state and the control values. However, if we allow the transformations to depend on the control at a functional level (open loop transformations), we are able to prove a version of the Grobman–Hartman theorem for control systems. 相似文献
4.
We consider the time delay of massive, non-relativistic, one-dimensional particles due to a tunneling potential. In this setting
the well-known Hartman effect asserts that often the sub-ensemble of particles going through the tunnel seems to cross the
tunnel region instantaneously. An obstacle to the utilization of this effect for getting faster signals is the exponential
damping by the tunnel, so there seems to be a trade-off between speedup and intensity. In this paper we prove that this trade-off
is never in favor of faster signals: the probability for a signal to reach its destination before some deadline is always
reduced by the tunnel, for arbitrary incoming states, arbitrary positive and compactly supported tunnel potentials, and arbitrary
detectors. More specifically, we show this for several different ways to define “the same incoming state” and “the same detector”
when comparing the settings with and without tunnel potential. The arrival time measurements are expressed in the time-covariant
approach, but we also allow the detection to be a localization measurement at a later time.
Dedicated to Pekka Lahti on the occasion of his 60th birthday. 相似文献
5.
1IntroductionConsiderthesecondorderordinarydiferentialequationx″+q(t)x=0,t≥0.(1.1)SupposethatQ(t)=∫+∞tq(s)ds(1.2)converges(po... 相似文献
6.
The resonant and non-resonant dynamies of a Gaussian quantum wave packet travelling through a double barrier system is studied
as a function of the initial characteristics of the spectrum and of the parameters of the potential. The behaviour of the
tunnelling time shows that there are situations where the Hartman effect occurs, while, when the resonances are dominant,
and in particular for b>π/Δk (b being the inter-barrier distance and Δk the spectrum width), the tunnelling time becomes very large and the Hartman effect
does not take place. 相似文献
7.
Bernd Aulbach 《Journal of Difference Equations and Applications》2013,19(3-4):283-296
In this paper, we continue the study of geometric properties of nonautonomous difference equations in arbitrary Banach spaces which was begun in [2,3]. Building on previous results on invariant fiber bundles and foliations, this paper addresses the problem of topological simplifications via continuous conjugacies and semiconjugacies. In particular, we establish a reduction principle for not necessarily invertible difference equations, as well as a generalized Hartman–Grobman theorem for systems with not necessarily invertible linear part. 相似文献
8.
We study the spin-dependent tunneling time, including group delay and dwell time, in a graphene based asymmetrical barrier with Rashba spin–orbit interaction in the presence of strain, sandwiched between two normal leads. We find that the spin-dependent tunneling time can be efficiently tuned by the barrier width, and the bias voltage. Moreover, for the zigzag direction strain although the oscillation period of the dwell time does not change, the oscillation amplitude increases by increasing the incident electron angle. It is found that for the armchair direction strain unlike the zigzag direction the group delay time at the normal incidence depends on the spin state of electrons and Hartman effect can be observed. In addition, for the armchair direction strain the spin polarization increases with increasing the RSOI strength and the bias voltage. The magnitude and sign of spin polarization can be manipulated by strain. In particular, by applying an external electric field the efficiency of the spin polarization is improved significantly in strained graphene, and a fully spin-polarized current is generated. 相似文献
9.
Some questions on the generalized Hartman effect presented by Kudaka and Matsumoto [S. Kudaka, S. Matsumoto, Phys. Lett. A 375 (2011) 3259] and a comment on them given by Milanovi? and Radovanovi? are discussed. 相似文献
10.