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121.
V. N. Paimushin V. A. Ivanov S. N. Bobrov T. V. Polyakova 《Mechanics of Composite Materials》2000,36(3):185-192
The solution of the stability problem of a circular sandwich ring under uniform external pressure is given in a refined statement.
The need to determinate the precritical stresses in load-bearing layers in the refined statement with regard to the transverse
compression of the core is established, which is the basis for the detection of the mixed flexural buckling forms (BFs) with
more than two half-waves along the circumferential coordinate (n>2). It is found that sandwich structures with a determining
parameter of transverse compression corresponding to the limit of transition from the mixed BFs to synphasic ones are the
most efficient from the weight viewpoint.
Translated from Mekhanika Kompozitnykh Materialov, Vol. 36, No. 3, pp. 317–328, May–June, 2000. 相似文献
122.
Henri Cohen. 《Mathematics of Computation》1996,65(216):1681-1699
We show how the usual algorithms valid over Euclidean domains, such as the Hermite Normal Form, the modular Hermite Normal Form and the Smith Normal Form can be extended to Dedekind rings. In a sequel to this paper, we will explain the use of these algorithms for computing in relative extensions of number fields.
123.
Joachim Gwinner 《Optimization》2018,67(7):1017-1030
AbstractThis paper is concerned with elliptic variational inequalities that depend on two parameters. First, we investigate the dependence of the solution of the forward problem on these parameters and prove a Lipschitz estimate. Then, we study the inverse problem of identification of these two parameters and formulate two optimization approaches to this parameter identification problem. We extend the output least-squares approach, provide an existence result and establish a convergence result for finite-dimensional approximation. Further, we investigate the modified output least-squares approach which is based on energy functionals. This latter approach can be related to vector approximation. 相似文献
124.
针对给出的函数y=f(x),x∈[a,b],将其值域进行n等分,设yi为其中任一分点,对应x=xi(i=1,2,…,m),用GM(1,1)模型对序列{x1,x2,…,xm}进行预测,得到曲线y=f(x)在下一段时间与直线y=yi的交点位置.当GM(1,1)模型的误差较大时,可利用带有残差修正的GM(1,1)模型进行残差修正,以提高GM(1,1)模型预测值的精确度. 相似文献
125.
In this paper, we considered the multiple rogue wave solutions of a (3+1)-dimensional Hirota bilinear equation by using a symbolic computation approach. Based on the bilinear form of this equation, the first-order rogue waves, the second-order rogue waves and the third-order rogue waves are presented. Moreover, some basic properties of multiple rogue waves and their collision structures are explained by drawing the three dimensional plot. 相似文献
126.
Volker D. Burkert 《中国物理 C》2009,33(12):1043-1050
Recent measurements of nucleon resonance transition form factors with CLAS at Jefferson Lab are discussed. The new data confirm the assertion of the symmetric constituent quark model of the Roper as the first radial excitation of the nucleon. The data on high Q2 nπ+ production better constrain the branching ratios liNK and [3Nn. For the first time, the longitudinal transition amplitude to the S11(1535) was extracted from the nπ+ data. Also, new results on the transition amplitudes for the D13(1520) resonance are presented showing a rapid transition from helicity 3/2 dominance seen at the real photon point to helicty 1/2 dominance at higher Q2. I also discuss the status of the search for new excited nucleon states. 相似文献
127.
B. Z. Shavarovskii 《Mathematical Notes》1998,64(5):663-673
The structure of polynomial matrices in connection with their reducibility by semiscalar-equivalent transformations and similarity
transformations to simpler forms is considered. In particular, the canonical form of polynomial matrices without multiple
characteristic roots with respect to the above transformations is indicated. This allows one to establish a canonical form
with respect to similarity for a certain type of finite collections of numerical matrices.
Translated fromMatematicheskie Zametki, Vol. 64, No. 5, pp. 769–782, November, 1998. 相似文献
128.
Within framework of zero curvature representation theory, a family of integrable rational semi-discrete systems is derived from a matrix spectral problem. The Hamiltonian forms of obtained semi-discrete systems are constructed by means of the discrete trace identity. The Liouville integrability for the obtained family is demonstrated. In the end, a reduced family of obtained semi-discrete systems and its Hamiltonian form are worked out. 相似文献
129.
Jiunn-Wei Chen Hiroaki Kohyama Kazuaki Ohnishi Udit Raha Yue-Long Shen 《Physics letters. [Part B]》2010
We present a combined analysis of the space- and time-like electromagnetic pion form factors in light-cone perturbative QCD with transverse momentum dependence and Sudakov suppression. Including the genuine non-perturbative “soft” QCD and the power suppressed twist-3 corrections to the standard twist-2 perturbative QCD result, the experimental form factor data available at moderate energies/momentum transfers can be explained reasonably well. To this end, the bulk of the existing discrepancy between the space- and time-like experimental data is ostensibly reconciled. 相似文献
130.
本文通过将高阶非线性自治微分方程转化为Lurie型控制系统的方法,借助于Popov的频率判据,得到了它们全局渐近稳定的判别准则,推广了文[1]的结果. 相似文献