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991.
Lijun Zhang Yue Wang Chaudry Masood Khalique Yuzhen Bai 《Journal of Applied Analysis & Computation》2018,8(6):1938-1958
The bounded traveling wave solutions of a generalized Camassa-Holm-Novikov equation with $p=2$ and $p=3$ are derived via the dynamical system approach. The singular wave solutions including peakons and cuspons are obtained by the bifurcation analysis of the corresponding singular dynamical system and the orbits intersecting with or approaching the singular lines. The results show that the generalized Camassa-Holm-Novikov equation with $p=2$ and $p=3$ both admit smooth solitary wave, smooth periodic wave solutions, solitary peakons, periodic peakons, solitary cuspons and periodic cuspons as well. It is worth pointing out that the Novikov equation has no bounded traveling wave solutions with negative wave speed, but has a family of new periodic cuspons which are distinguished with the normal periodic cuspons for their discontinuous first-order derivatives at both maximum and minimum. 相似文献
992.
Dynamic analysis of a non-autonomous ratio-dependent predator-prey model with additional food 下载免费PDF全文
Jie Song Mi Hu Yuzhen Bai Yonghui Xia 《Journal of Applied Analysis & Computation》2018,8(6):1893-1909
In this paper, a non-autonomous ratio-dependent three species predator-prey system with additional food to top predator was proposed. The permanence of the model is obtained. Based on the continuation theorem, the sufficient conditions for the existence of a periodic solution are obtained. By using the method of Lyapunov function, we prove that the system exists a unique positive almost periodic solution under some certain conditions. 相似文献
993.
C. H. Lin L. Jiang Y. H. Chai H. Xiao S. J. Chen H. L. Tsai 《Applied Physics A: Materials Science & Processing》2009,97(4):751-757
This article reports the fabrication of high-fill-factor plano-convex cylindrical and spherical microlens arrays horizontally
and vertically embedded in a photosensitive Foturan glass chip by femtosecond (fs) laser micromachining. The microlens arrays
were fabricated by modifying the microstructure of Foturan glass using fs laser direct writing followed by thermal treatment,
wet etching, and additional annealing. The focusing ability and image quality of the microlens arrays were examined, showing
that the lens arrays not only can focus light well but also provide an imaging capability that holds great potential for lab-on-a-chip
applications. 相似文献
994.
995.
一种快速双目视觉立体匹配算法 总被引:11,自引:0,他引:11
针对目前双目视觉立体匹配算法计算量过大、实时性不强的问题,提出了一种平行配置系统的快速立体匹配算法.利用两幅视图的差异将视图分为特征点和非特征点,然后对特征点采用WTA(winner-take-all)方法进行匹配,而对非特征点只进行简单的验证,最后得出致密的视差图.该算法利用视差的分段连续性,大大减少了运算量.实验结果表明,该算法提取的特征点集中于视差不连续区,与目前其它基于区域的匹配算法相比,该算法得到的误匹配像素百分比与其它算法相当,而计算速度却提高了一个数量级,并且边缘特征较好,是一种有效可行的高实时性立体匹配算法. 相似文献
996.
997.
C.H. Sun Y.S. Chai J. Liu H.X. Gao L. Cheng J.B. Wang L.Z. Cao 《Journal of Physics and Chemistry of Solids》2009,70(2):286-290
The experiments of electrical resistivity and thermopower on Nd0.75Sr1.25CoO4 film in the temperature range 90 K<T<310 K were carried out. The great difference in the activation energies estimated from thermopower and resistivity, a characteristic of small polarons, is observed, providing strong evidence for polaron-dominated transport mechanism in this material. Furthermore, the activation energy at intermediate-temperature region is larger than that at low-temperature region in resistivity, but it is not observed in thermopower, indicating that the energy for the creation of the carriers is slightly lower at low-temperature region than that at intermediate-temperature region. At the same time, the abrupt drop in the thermopower and the abnormal peak in the differential curve of resistivity indicate that a phase transition between a paramagnetic state and a ferromagnetic state occurs at temperature about 218 K. The positive thermopower in the whole temperature range measured suggests that the carriers are holes in this system. 相似文献
998.
Yuzhen Guo Enmin Feng Zikaio Wu Jincheng Zhao 《Journal of Applied Mathematics and Computing》2006,22(3):381-391
Protein structure alignment is one of the most important computational problems in molecular biology. From the viewpoint of computational complexity, a pairwise structure alignment is a NP-hard problem. In this paper, based on the discrepancy of two proteins, we define the structure alignment as a mixed integer-programming (MIP) problem with the simpler form and prove the existence of optimal solution. The optimal alignment is achieved by incorporating improved complete information set method used to modify the score matrix into iterative double dynamic programming algorithm. Convergence of algorithm is proved. A number of benchmark examples are tested. The results show that our model and approach are general and improve computational efficiency as well as quality of the structure alignment. 相似文献
999.
In this paper, we have investigated the grating erasure of a reduced LiNbO3:Fe crystal with different erasing wavelengths. The overall hologram evolution in the process of grating erasure is nonexponential due to strong absorption which is contrary to the mono-exponential law. The hologram in the rear part of the crystal can persist for a long time in the grating erasure due to weak erasing light intensity by strong absorption, which can enlarge the erasure time constant. From the erasure experiments, the global absorption d≈5 can be taken as the optimum absorption to acquire a good trade-off between the sensitivity and hologram strength in the crystal. 相似文献
1000.
CHEN Jing & BAI Yuzhen Department of Mathematics Nanjing University Nanjing China Department of Mathematics Qufu Normal University Qufu China 《中国科学A辑(英文版)》2006,49(12):1864-1866
Mane conjectured that every minimal measure in the generic Lagrangian systems is uniquely ergodic. In this paper, we will show that the answer to the Mane's conjecture is negative by analyzing the structure of the supports of minimal probability measures for some kinds of the Lagrangian systems. 相似文献