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排序方式: 共有623条查询结果,搜索用时 29 毫秒
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DONG GuoXiang YU ShaoYing LIU YanXin SHEN CaiWan & DONG YongSheng I School of Science Huzhou Teachers College Huzhou China School of Science Information Engineering Zhejiang Normal University Jinhua 《中国科学:物理学 力学 天文学(英文版)》2010,(1)
Theoretical calculations of the energy bands in nucleus 102 Zr are carried out by taking the projected shell model approach, which has reproduced the experimental data. In addition, by analyzing band-head energies, corresponding configurations of yrast band, quasi-particle rotational bands and side bands, we have worked out the microscopic formation mechanism of axially symmetric deformation bands: The low-excitation deformation bands are attributed to the high-j intruder states 1g 7/2 and 1h 11/2 in the N=... 相似文献
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LU ZhiXin YU Li LI Kang LIU BingCan LIN JianGui JIAO RongZhen & YANG BoJun School of Science Beijing University of Posts Telecommunications Beijing China Key Laboratory of Information Photonics Optical Communication Ministry of Education 《中国科学:物理学 力学 天文学(英文版)》2010,(1)
An efficient and practical post-processing technique based on reverse reconciliation for continuous variable quantum key distribution is proposed and simulated with low-density parity check (LDPC) codes. MultiLevel Coding/ MultiStage Decoding, which fully utilizes optimization technique such as vector quantization and iterative decoding and the optimal channel coding most close to the Shannon limit, was used to realize efficient reverse reconciliation algorithm. Simulation results showed that the proposed m... 相似文献
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Analytical self-similar solutions of the Ginzburg-Landau equation with three-order dispersion effect
Based on the technique of the symmetry reduction, we find the asymptotic self-similarity analytical resolutions from the constant coefficient Ginzburg-Landau equation considering both influences of the thirdorder dispersion and gain dispersion on the evolution of pulses. We have obtained the self-similar pulse amplitude function, phase function, strict linear chirp function, and the effective temporal pulse width. Numerical simulations show qualitative agreement with these theoretical results. 相似文献
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<正>Wavefront coding(WFC) is used to extend the field depth of an incoherent optical system by employing a phase mask on the pupil.We uses a Fisher information(FI) metric based optimization method to design a phase mask by taking the modulation transfer function(MTF) of the practical optical system into consideration. This method can modulate the wavefront so that the point spread function and optical transfer function are insensitive to the object distance.The simulation results show that the optimized phase mask based on the proposed method can further improve the defocusing image quality while maintaining the focusing image quality. 相似文献
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何忠蛟 《中国光学快报(英文版)》2010,(3):259-261
<正>A novel band-rejection filter based on a Bragg fiber with a defect layer is proposed.A defect layer is introduced in the periodic high/low index layers in the cladding of the Bragg fiber,which results in large confinement loss for some resonant wavelengths inside the band gap range of the Bragg fiber.A segment of the Bragg fiber with a defect layer can be used as a band-rejection filter,whose characteristics are mainly determined by the structure of the Bragg fiber.The simulation results show that the bandwidth of such a band-rejection filter is dependent on the number of the periodic high/low index layers in both sides of the defect layer in the cladding of the Bragg fiber. 相似文献