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191.
有界凸圆型域上的准凸映照 总被引:7,自引:1,他引:6
本文研究星形映照的一类子族——有界凸圆型城上的准凸映照,并讨论了它与星形映照及凸映照的关系,建立其与凸映照同形的增长定理和掩盖定理. 相似文献
192.
Sergiu Shova Vasile Tiron Angelica Vlad Ghenadie Novitchi Dan G. Dumitrescu Madalin Damoc Mirela-Fernanda Zaltariov Maria Cazacu 《应用有机金属化学》2020,34(12):e5957
A di-manganese(III) complex structure was built by an original approach consisting of a two-step procedure. First, the mononuclear complex of the manganese(III) with the Schiff base of the salen-type ligand (H2L) derived from 1,3-bis(3-aminopropyl)tetramethyldisiloxane and 3,5-di-tert-butyl-2-hydroxybenzaldehyde was prepared. The main feature of note is the 12-membered chelate ring formed upon coordination of the Schiff base to central atom, which adopts a distorted N2O4 octahedron environment. In the second step, the acetato co-ligand in this complex is replaced by the carboxylate anion of a dicarboxilic acid, namely adipic acid. This metathesis reaction leads to the formation of dinuclear structure by connecting two manganese centers. The structure, as was determined by X-ray single crystal diffractometry, elemental and spectral analysis, is permethylated dinuclear complex with long aliphatic bridge. Thermal and magnetic properties were studied. In addition, the formation of magnetically induced stripe-ordered domains was highlighted by the magnetic force microscopy (MFM) on films born from diluted solution. 相似文献
193.
194.
Bernd Flemisch Barbara I. Wohlmuth 《Numerical Methods for Partial Differential Equations》2004,20(3):374-387
A one directionally coupled problem on two nested domains is analyzed. The global domain and the subdomain are discretized by two triangulations that do not match on the subdomain. The connection between the two grids is established by using a stable projection operator onto the interface. An a priori error analysis is carried out and several numerical examples are given. The method is ideally suited for the case of a moving subdomain. © 2004 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 20: 374–387, 2004. 相似文献
195.
积域上的一类粗糙奇异积分算子 总被引:4,自引:0,他引:4
本文讨论了积域Rn×Rm上一类带粗糙核的奇异积分算子Tf(x,y)=p.v.Rn×RmΩ(u,v)|u|n|v|mh(|u|,|v|)f(x-u,y-v)dudv的Lp(Rn×Rm)有界性.这里,Ω为原子Hardy空间H1a(Sn-1×Sm-1)中的函数且h为空间l∞(Lq)(R+×R+)中的径向函数. 相似文献
196.
197.
Isabel Escudero 《The Journal of Mathematical Behavior》2007,26(4):312-327
This study is a part of a research project that seeks to characterize the relationship between mathematics teachers’ knowledge and their practice. In this paper, we focus on identifying the characteristics of subject matter knowledge and pedagogical content knowledge that two teachers integrate in decisions they make about the introduction of specific mathematical content. Then, we examine the changes that arise in their classrooms as their plans are put in action. Data were obtained through audiotapes of several semi-structured interviews, through observations, and through videotapes. Although the two teachers in this study had similar backgrounds and experiences, our analysis shows differences in the characteristics of the domains of knowledge they integrated in their planning as well as differences in the adaptations that each made in the classroom. In this sense, this study contributes to better understanding the complexity of teachers’ professional practice. 相似文献
198.
Hideo Ueda 《Annals of Global Analysis and Geometry》1998,16(5):477-495
In this paper a Dirichlet problem for the Laplacian in a domain with a corner in R2 is treated and a new method of construction of a local parametrix for that Dirichlet problem at a corner point is given. In order to construct a parametrix a certain class of operators in a slab domain is introduced and it is shown that that operator class is an algebra. 相似文献
199.
P. N. Shankar 《Proceedings Mathematical Sciences》2006,116(3):361-371
The recently suggested embedding method to solve linear boundary value problems is here extended to cover situations where
the domain of interest is unbounded or multiply connected. The extensions involve the use of complete sets of exterior and
interior eigenfunctions on canonical domains. Applications to typical boundary value problems for Laplace’s equation, the
Oseen equations and the biharmonic equation are given as examples. 相似文献
200.
A. R. Maikov 《Computational Mathematics and Mathematical Physics》2006,46(6):1007-1022
Initial-boundary value problems formulated in spatially unbounded domains can be sometimes reduced to problems in their bounded subdomains by using the so-called open boundary conditions. These conditions are set on the surface separating the subdomain from the rest of the domain. One of the approaches to obtaining such a kind of conditions is based on an approximation of the kernels of the time convolution operators in the relations connecting the exact solution of the original problem and its derivatives on the open boundary. In this case, it is possible to considerably reduce the requirements for system resources required to solve numerically for a wide range of physical and engineering problems. Estimates of the perturbations of the exact solution due to the approximate conditions are obtained for a model problem with one space variable. 相似文献