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排序方式: 共有511条查询结果,搜索用时 406 毫秒
11.
A. A. Tolstonogov 《Set-Valued Analysis》1998,6(2):129-147
Existence theorems of continuous selectors whose values are fixed points of multivalued contractions are proved. As an application, the existence of continuous selectors to generalized solution sets of partial differential inclusions, depending on a parameter, is obtained. 相似文献
12.
Uwe Bandelow Mindaugas Radziunas Andrei Vladimirov Bernd Hüttl Ronald Kaiser 《Optical and Quantum Electronics》2006,38(4-6):495-512
We study both theoretically and experimentally typical operation regimes of 40 GHz monolithic mode-locked lasers. The underlying
Traveling Wave Equation model reveals quantitative agreement for characteristics of the fundamental mode-locking as pulse
width and repetition frequency tuning, as well as qualitative agreement with the experiments for other dynamic regimes. Especially
the appearance of stable harmonic mode-locking at 80 GHz has been predicted theoretically and confirmed by measurements. Furthermore,
we derive and apply a simplified Delay-Differential-Equation model which guides us to a qualitative analysis of bifurcations
responsible for the appearance and the breakup of different mode-locking regimes. Higher harmonics of mode-locking are predicted
by this model as well. 相似文献
13.
N. V. Kas’yan A. V. Shvets S. A. Sergienko V. G. Il’in 《Theoretical and Experimental Chemistry》2006,42(4):255-259
The zeolite IPC-3, isomorphous with germanate zeolite ASU-16, and its silicon, aluminum, and titanium analogs, were obtained
in the presence of 1,6-diaminohexane as a template. It is possible to incorporate selectively the elements in different crystallographic
positions, determined by the nature of the element, particularly its valency and its coordination number with respect to oxygen.
Silicon takes tetrahedral positions in the IPC-3 lattice, Al either tetrahedral or octahedral positions, and Ti octahedral
positions. Small amounts of the lithium cations facilitate tetrahedral coordination and increase the Al content in IPC-3.
__________
Translated from Teoreticheskaya i éksperimental’naya Khimiya, Vol. 42, No. 4, pp. 246–251, July–August, 2006. 相似文献
14.
Hybrid systems with memory are dynamical systems exhibiting both delayed and hybrid dynamics. Such systems can be described by hybrid functional inclusions. Classical invariance principles play an instrumental role in proving stability and convergence of dynamical systems. Invariance principles for general hybrid systems with delays, however, remain an open topic. In this paper, we prove invariance principles for hybrid systems with memory, using both Lyapunov–Razumikhin function and Lyapunov–Krasovskii functional methods. These invariance principles are then applied to derive two stability results as corollaries. 相似文献
15.
We consider a transmission problem on a polygonal partition for the two-dimensional conductivity equation. For suitable classes of partitions we establish the exact behaviour of the gradient of solutions in a neighbourhood of the vertexes of the partition. This allows to prove shape differentiability of solutions and to establish an explicit formula for the shape derivative. 相似文献
16.
G. Gebhardt 《Isotopes in environmental and health studies》2013,49(10):347-349
Zur Isolierung von Einshlüssen aus hochlegierten Stählen werden die Hauptkomponenten Fe, Ni, Cr und weitere Metalle durch mehrstufig ausgeführte Flüssig-Flüssig-Extraktionen mit verschiedenen Extraktionsmitteln abgetrennt. Die im Eindampfrückstand der wäβrigen Phase nach der Extraktion verbleibenden Einschlüsse können für die meisten Radionuklide ohne nennenswerte Selbstabsorption mit einem Groβflächenzählrohr oder anderen geeignetenZählvorrichtungen ausgemessen werden. 相似文献
17.
研究含双周期分布的圆形刚性夹杂在无穷远受纵向剪切的弹性平面问题,遵循复合材料中各夹杂相互影响的重要条件。采用复变函数方法。构造相应模型的复应力函数。通过坐标变换,同时满足夹杂边界位移条件,再利用围线积分将求争方程组化为线性代数方程组。导出了圆形刚性夹杂双周期分布的界面应力解析表达式。算例给出了界面应力最大值与夹杂间距的变化规律。求出了刚性夹杂的合理间距问题,本文发展的分析方法为研究夹杂材料的细观机理探索了一条有效的分析途径。 相似文献
18.
《Optimization》2012,61(3-4):325-338
Asymptotic properties of reachable sets of singularly perturbed differential inclusions are given. Their applications to optimal control problems are also studied 相似文献
19.
Zeph A. Landau 《Geometriae Dedicata》2002,95(1):183-214
An inclusion of II
1 factors NM of finite index has as an invariant, a double sequence of finite-dimensional algebras known as the standard invariant. Planar algebras were introduced by V. Jones as a geometric tool for computing standard invariants of existing subfactors as well as generating standard invariants for new subfactors. In this paper we define a class of planar algebras, termed exchange relation planar algebras, that provides a general framework for understanding several classes of known subfactor inclusions: the Fuss–Catalan algebras (i.e. those coming from the presence of intermediate subfactors) and all depth 2 subfactors. In addition, we present a new class of planar algebras (and thus a new class of subfactors) coming from automorphism subgroups of finite groups. 相似文献
20.
Motivated by the applications to differential equations without uniqueness conditions, we separately prove multivalued versions of the celebrated Sharkovskii and Li–Yorke theorems. These are then applied, via multivalued Poincaré operators, to Carathéodory differential inclusions. Thus, besides another, infinitely many subharmonics of all integer orders can be obtained. Unlike in the single-valued case, for example, period three brings serious obstructions. Three counter-examples, related to these complications, are therefore presented as well. In a multivalued setting, new phenomena are so exhibited. 相似文献