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421.
通过计算和分析周期聚焦磁场强度和表征束自生场强度的束导流系数的变化对强流粒子束运动特征的影响,系统研究了强流粒子束的非线性共振和束晕现象。采用庞加莱截面技术对束核包络振荡及其单粒子运动轨迹进行了数值模拟,清楚地展示了不同情况下束核包络非线性振荡以及对应的试验粒子空间分布。结果表明:束核自生场使得束核包络发生非线性振荡,随着束核自生场和聚焦磁场的增加,伴随着束核共振岛的出现,单粒子空间分布出现越来越多的束晕粒子。  相似文献   
422.
首先研究了加倍周期序列的奇异词,进而得到序列的奇异分解.然后通过研究该序列的特殊诃和因子性质及结构,得到复杂度的新的计算方法.最后探讨了加倍周期序列的局部同态问题.  相似文献   
423.
An algorithm of generating graph structures for the ordering of datasets is proposed. It operates with the key concept of “sphere neighborhood” and generates the graph structured ordering of datasets, provided the elements of such sets can be related by some similarity relation. The algorithm always allows determining the shortest path between two nodes in a constructive way. It is demonstrated by an application to the famous Word Morph game and in addition to the ordering of logfiles with respect to the detection of errors. Therefore, the algorithm can be very useful for the dealing with Big Data problems. © 2016 Wiley Periodicals, Inc. Complexity 21: 426–436, 2016  相似文献   
424.
孙丽萍  刘文德 《数学学报》2021,64(1):167-176
本文将模李代数中环面与环面秩的理论推广到模李超代数中.应用模李超代数的限制包络得到了环面秩的若干重要性质.作为应用,计算了典型李超代数slm|n与限制Cartan型李超代数W(m,n,1),S(m,n,1)的绝对环面秩及S(m,n,1)在W(m,n,1)中的环面秩.  相似文献   
425.
In this paper, we explore some properties of the Moreau envelope function eλf(x) of f and the associated proximal mapping Pλf(x) in the sense of the Bregman distance induced by a convex function g. Precisely, we study the continuity, differentiability, and Clarke regularity of the Moreau envelope function and the upper semicontinuity and single-valuedness of the proximal mapping as well as its relation to the convexity of λf+g, where λ is a positive parameter.  相似文献   
426.
The starting point of this work is a paper by Alvarez, Lasry and Lions (1997) concerning the convexity and the partial convexity of solutions of fully nonlinear degenerate elliptic equations. We extend their results in two directions. First, we deal with possibly sublinear (but epi-pointed) solutions instead of 1-coercive ones; secondly, the partial convexity of C2 solutions is extended to the class of continuous viscosity solutions. A third contribution of this paper concerns C1,1 estimates for convex viscosity solutions of strictly elliptic nonlinear equations. To finish with, all the tools and techniques introduced here permit us to give a new proof of the Alexandroff estimate obtained by Trudinger (1988) and Caffarelli (1989).  相似文献   
427.
In this work, we present the modeling of three-phase vapor–liquid–liquid equilibria for a mixture of natural gas (Hogback gas) containing high concentrations in nitrogen (51.8 mol%) with the SRK and PC-SAFT equations of state. The interest of studying this mixture is due to the experimental evidence of the occurrence of multiple equilibrium liquid phases for this mixture over certain ranges of temperature and pressure. The calculation of the multiphase equilibria was carried out by using an efficient numerical procedure based on the minimization of the system Gibbs energy and thermodynamic stability tests to find the most stable state of the system. The results of the calculated vapor–liquid–liquid equilibria (VLLE) show that the PC-SAFT equation of state predicts satisfactorily the phase behavior that experimentally exhibits this mixture, whereas the SRK equation of state predicts a three-phase region wider than the experimentally observed. The two-phase boundary for this mixture was also calculated through flash calculations, and the results showed that this mixture does not present any gas-liquid critical point.  相似文献   
428.
证明了反射型的带跳倒向双重随机微分方程的解的存在唯一性.主要方法是Snell包和不动点定理.  相似文献   
429.
Assume that K⊂Rnm is a convex body with o∈int(K) and is a function with f|K∈C0(K,R) and f|(Rnm?K)≡+∞. We show that its lower semicontinuous quasiconvex envelope
  相似文献   
430.
In this paper we show existence and uniqueness of a solution for a system of m variational partial differential inequalities with inter-connected obstacles. This system is the deterministic version of the Verification Theorem of the Markovian optimal m-states switching problem. The switching cost functions are arbitrary. This problem is in relation with the valuation of firms in a financial market.  相似文献   
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