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排序方式: 共有3256条查询结果,搜索用时 15 毫秒
991.
992.
A continuous g-frame is a generalization of g-frames and continuous frames, but they behave much differently from g-frames due to the underlying characteristic of measure spaces. Now, continuous g-frames have been extensively studied, while continuous g-sequences such as continuous g-frame sequence, g-Riesz sequences, and continuous g-orthonormal systems have not. This paper addresses continuous g-sequences. It is a continuation of Zhang and Li, in Numer. Func. Anal. Opt., 40 (2019), 1268-1290, where they dealt with g-sequences. In terms of synthesis and Gram operator methods, we in this paper characterize continuous g-Bessel, g-frame, and g-Riesz sequences, respectively, and obtain the Pythagorean theorem for continuous g-orthonormal systems. It is worth that our results are similar to the case of g-ones, but their proofs are nontrivial. It is because the definition of continuous g-sequences is different from that of g-sequences due to it involving general measure space. 相似文献
993.
Gui Yu Yang 《数学学报(英文版)》2011,27(8):1645-1654
In this paper we describe explicitly the generating relations for the Grothendieck groups of trivial extension algebras of
tame hereditary algebras. 相似文献
994.
995.
DONG WeiPing* CHEN Zheng & WANG YongXin State Key Laboratory of Solidification Processing Northwestern Polytechnical University Xi’an China 《中国科学:物理学 力学 天文学(英文版)》2011,(5)
Based on the phase field theory, the phase precipitation sequence of Ni75Al10Cr15 alloy and the free energy of each phase were studied. Moreover, the interatomic potentials of L10 phase, L12 phase and DO22 phase changing with temperature and concentrations were computed through utilizing the interatomic potentials equations induced by Khachaturyan’s relational equations between the interatomic potentials and the long-range order (LRO) parameters. Results match preceding work and demonstrate that the phase p... 相似文献
996.
997.
Some convergence theorems of Ishikawa type iterative sequence with errors for nonlinear general quasi- contractive mapping in convex metric spaces are proved. The results not only extend and improve the corresponding results of L . B . Ciric , Q . H. Liu , H. E. Rhoades and H. K. Xu , et al. , but also give an affirmative answer to the open question of Rhoades-Naimpally-Singh in convex metric spaces . 相似文献
998.
相关地磁匹配定位技术 总被引:12,自引:4,他引:12
地磁匹配定位算法的本质是数字地图匹配,相关匹配算法是数字地图匹配的有效算法。在地磁导航中该匹配算法自适应实时构造基准数据序列,并以Hausdorff距离作为相关判断准则。为了提高了算法实时性,提出了预匹配和精匹配相结合的改进措施优化了运算过程。在预匹配过程中,由于地磁数据的离散性,搜索步长定为一个基本网格单元,并与序贯相似检测原则相结合,这样可快速排除非匹配区,筛选得到精匹配所需要的可行区域。在精匹配中,引入了双线性插值法对地磁场原始数据进行加密内插以提高匹配精度。最后利用地磁场数据进行了仿真试验,结果表明在一定条件下该相关匹配算法对地磁导航具有适用性。 相似文献
999.
刘国栋 《应用数学和力学(英文版)》2002,23(11):1348-1356
IntroductionThekthorderN rlundEulerpolynomialsE(k)v (x|ω1,… ,ωk)andBernoullipolynomialsB(k)v (x|ω1,… ,ωk)aregivenbythefollowingexpansionformularespectively[1]2 kext(eω1 t+ 1 )… (eωkt+ 1 ) = ∞v=0E(k)v (x|ω1,… ,ωk) tvv!,( 1 )ω1…ωktkext(eω1 t-1 )… (eωkt-1 ) = ∞v=0B(k)v (x|ω1,… ,ωk) tvv!. ( 2 )Clearlyt… 相似文献
1000.
The controllability for switched linear systems with time-delay in controls is first investigated. The whole work contains
three parts. This is the third part. The definition and determination of controllability of switched linear systems with multiple
time-delay in control functions is mainly investigated. The sufficient and necessary conditions for the one-periodic, multiple-periodic
controllability of periodic-type systems and controllability of aperiodic systems are presented, respectively. Finally, the
case of distinct delays is discussed, it is shown that the controllability is independent of the size of delays.
Contributed by YE Qing-kai
Foundation items: the National Natural Science Foundation of China (69925307, 60274001); the National Key Basic Research and Development Program
(2002CB312200); the Postdoctoral Program Foundation of China
Biography: XIE Guang-ming (1972≈), Doctor (E-mail:xiegming@mech.pku.edu.cn) 相似文献