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991.
The sinh-Gordon equation expansion method is further extended by generalizing the sinh-Gordon equation and constructing new ansatz solution of the considered equation. As its application, the (2+1)-dimensional Konopelchenko-Dubrovsky equation is investigated and abundant exact travelling wave solutions are explicitly obtained including solitary wave solutions, trigonometric function solutions and Jacobi elliptic doubly periodic function solutions, some of which are new exact solutions that we have never seen before within our knowledge. The method can be applied to other nonlinear evolution equations in mathematical physics.  相似文献   
992.
The Elementary Goldstone Higgs(EGH) model is a perturbative extension of the standard model(SM),which identifies the EGH boson as the observed Higgs boson. In this paper, we study pair production of the EGH boson via gluon fusion at the LHC and find that the resonant contribution of the heavy scalar is very small and the SM-like triangle diagram contribution is strongly suppressed. The total production cross section mainly comes from the box diagram contribution and its value can be significantly enhanced with respect to the SM prediction.  相似文献   
993.
Bing Tang 《中国物理C(英文版)》2021,45(5):055101-055101-10
Based on the Melnikov method, we investigate chaotic behaviors in the extended thermodynamic phase space for a slowly rotating Kerr-AdS black hole under temporal and spatial perturbations. Our results show that the temporal perturbation coming from a thermal quench of the spinodal region in the phase diagram may cause temporal chaos only when the perturbation amplitude is above a critical value, which involves the angular momentum J. Under the spatial perturbation, however, it is found that spatial chaos always occurs, independent of the perturbation amplitude.  相似文献   
994.
995.
During the thermal evolution of the universe, symmetry of the vacuum state in the presence of quantum fields should have changed at various stages. A possible indication of this effect on the DFSZ invisible axion model of the Peccei-Quinn CP conserving mechanism is presented here. To start with, the background theory of this mechanism in the cosmic evolution has been fully reviewed, as well as the leading cosmological arguments setting limits on the mass and coupling of such a particle. The CP conserving lagrangian of the invisible axion model also includes instanton gauge field configurations. In our opinion, these configurations could behave non trivially while decreasing the temperature as a consequence of the vacuum symmetry modifications. The interplay between symmetry modifications and cosmic evolution may thus lead to yet unclear effects. In fact, the model considered here is really quite a baby version of the real world, so that only preliminary indications and bare consistency arguments have been done from it. Nevertheless, the underlying idea, a possible neutral Higgs fields approximate resonance condition, seems to survive even in more sophisticated models.  相似文献   
996.
This paper describes a function space algorithm for the solution of a class of linear-quadratic optimal control problems.The research of the first author was supported by Senate Research Grant No. 8.187.17, University of Ilorin, Ilorin, Kwara State, Nigeria.The authors thank two anonymous referees for their useful and challenging suggestions and comments which improved the quality of this paper. The authors are also indebted to I. Orisamolu for carrying out the computing work.  相似文献   
997.
在扩展有限元的框架内,本文发展了一种构造裂尖单元位移场的方法。整个裂纹沿程两侧的非连续位移场只通过富集变换的阶梯函数表征,在裂尖单元,通过调整形函数使得非连续性严格地消失于裂纹尖端。在避免混合区单元引入不满足单位分解的附加位移项的同时,实现了裂纹尖端单元位移场部分非连续特性的表达。还对裂尖单元的形函数调整原则进行了分析,以平面四节点单元为例提出了两种调整方式。文中裂尖单元中含有曲折裂纹的算例说明了本文方法的有效性和适用性。  相似文献   
998.
改进的曲波变换图像融合方法   总被引:1,自引:0,他引:1  
考虑将曲波变换引入图像融合能够更好地提取原始图像,对一种新的图像融合方法—曲波变换图像融合法进行了研究。将图像序列进行曲波变换后,通过对所有图像的高频进行逆变换及域值处理来获得区域图。根据区域图中高频区域的边界点在每张图层上的活跃度不同求得区域边界的图层分布,利用插值获得高频区域的区域分布图。通过高频区域的膨胀求得整幅图的区域分布图,然后在曲波变换的变换域,利用区域分布图对多尺度的高频系数采用高斯加权求和;对低频系数采用取平均值的规则完成图像的融合。进行了图像融合实验,实验结果表明,与传统的小波变换及基于像素的曲波变换相比,提出的方法获得的融合图像边缘更清晰,更接近参考图像。  相似文献   
999.
The evasion of massless Goldstone bosons by the non-abelian Higgs mechanism is proved by a non-perturbative argument in the local BRST gauge.  相似文献   
1000.
The accurate pKa determinations for three carboxylic acids have been investigated using the combination of the extended clusters‐continuum model at B3LYP/6‐31+g(d,p) and B3LYP/6‐311++g(d,p) levels. To take into account of the effect of the water combined with carboxylic acids in different positions, eleven molecular clusters were considered. Among these clusters, the one involving the carboxylic acid wrapped up with water molecules and saturated with hydrogen bonds (four hydrogen bonds around ? COOH) leads to the best B3LYP pKa results compared to the experimental data. For those clusters saturated with hydrogen bonds, when n = 3 (the number of water molecules), the average absolute errors between the calculated pKa results and experimental data of these three carboxylic acids were 0.19 (0.23) and 0.12 (0.22) pKa at B3LYP/6‐31+g(d,p)//PCM (IEFPCM) and B3LYP/6‐311++g(d,p)//PCM (IEFPCM) levels, respectively; when n = 4, they are 0.53 (1.23) and 1.09 (1.03) pKa, respectively. On the basis of the above results, the molecular cluster saturated with four hydrogen bonds formed by three waters and one carboxylic acid molecule was the chief existence in the carboxylic acid solution. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2012  相似文献   
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