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71.
S. J. Cheng W. Sheng P. Hawrylak S. Raymond S. Studenikin A. Sachrajda Z. Wasilewski A. Babinski M. Potemski G. Ortner M. Bayer 《Physica E: Low-dimensional Systems and Nanostructures》2004,21(2-4):211
We present results of calculations and experiments on electron–hole complexes in InGaAs/GaAs self-assembled quantum dots in high magnetic field (B). Due to hidden symmetries, the chemical potential of an N-exciton system at special B fields becomes insensitive to the exciton number as well as the magnetic field. This results in plateau regions of high intensity in measured magneto-PL spectrum. Theoretical calculations using exact diagonalization techniques successfully explain the measured magneto-photoluminescence spectrum with B fields up to 28 T. 相似文献
72.
73.
程晓雷 《信息安全与通信保密》2005,(6):118-120
背景和意义劳动保障部门作为统一管理和组织协调社会劳动力,统筹城乡就业,规划、引导劳动力市场的发展,组织建立健全就业服务体系,负责社会保障基金的缴纳、记录、核算、支付的部门,运用信息技术来实现劳动保障管理工作的电子化、自动化和网络化,更科学、更迅速、更准确地汇集、加工、传递、运用各类信息,是社会保障电子政务系统建设的重要内容,也是加快由行政管理向社会服务转化的突破口。随着社会保障电子政务系统建设的不断深入以及网络技术的发展,基于Internet的网上应用已逐步开展。如参保单位的网上申报、网上缴费以及信息查询等。这… 相似文献
74.
A subspace detection method of analog space-time codes for multiantenna ultra-wideband transmissions
Xiantao Cheng Weile Zhu 《Communications Letters, IEEE》2005,9(6):493-495
In this letter, we propose a subspace based detection method for space-time block codes (STBC) wedded with ultra-wideband (UWB) transmissions. Without the need of channel information, the proposed algorithm yields the estimation of transmitted symbols by minimizing some quadratic form built on the orthogonality between signal and noise subspaces. Simulations in flat-faded application scenarios show that the subspace method can achieve the same diversity and a loss of about 2 dB at the 10/sup -3/ level with more than four successive space-time codes being decoded jointly, compared to the coherent decoding algorithm. 相似文献
75.
76.
基于EAI的多层分布式应用与实现 总被引:5,自引:0,他引:5
针对目前大型企业各类应用迅速增加但应用之间缺乏有效通信的问题,采用企业应 用集成(EAI)技术,提出了4层分布式应用体系结构,实现流程自动化和松耦合的应用集成.文中首先从EAI技术和常见解决方案出发,详细阐述了表示层、企业门户、EAI总线层和数据源层的功能及软件结构,并结合电信业务运营支撑系统的实际需求,给出了J2EE平台下的应用实例开发.利用组件和容器的技术构建企业门户,通过工作流和企业Java组件(EJB)技术实现EAI总线,借助资源适配器完成应用之间的互连互通.该系统现已投入实际运行,取得了良好的应用效果. 相似文献
77.
Hsing-Chung Liang Wen-Chin Ho Ming-Chieh Cheng 《Reliability, IEEE Transactions on》2005,54(2):358-365
In this paper, we discuss some strategies for identifying unrepairable memories, and from that to introduce a novel theorem that can make more precise identification. A new algorithm for searching repair solutions is also proposed, which characterizes the rows, and columns of defective memory cells with revised effective coefficients. We have simulated it on many generated example maps, and compared it with the previous algorithms to verify its efficiency. It's combined with those arranged strategies of judging unrepairability to generate a complete flow. The complete algorithm has also been run on many examples with various memory sizes, defect numbers, and distribution types. The simulation results further show that identifying unrepairability in advance can help the reconfiguration procedure run much faster than searching solutions directly. 相似文献
78.
A new frequency notched ultra-wideband microstrip slot antenna with a parasitic tuning stub is proposed. The antenna is similar in configuration to a conventional microstrip slot antenna; by introducing a parasitic open-circuit tuning stub, flexible frequency notched function is achieved. Several properties of the antenna, such as frequency notched function, antenna transfer function and gain, have been investigated. As is reported, the operation bandwidth of the antenna is 2.91-11.16 GHz, in which a frequency notched band of 5.10-5.85 GHz has been achieved. Furthermore, good ultra-wideband linear transmission performance over the entire operation frequency range has also been achieved. 相似文献
79.
Ching‐Yuan Cheng Kuan‐Jiuh Lin 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(8):m363-m365
In the title compound, catena‐poly[lithium‐μ3‐ethylenediphosphonato], [Li(C2H7O6P2)]n, the supramolecular monoclinic (C2/c) structure consists of one‐dimensional lithium chains [Li⋯Li = 2.7036 (8) Å] that are embedded within ethylenediphosphonate anions linked by strong symmetric hydrogen bonds [O⋯O = 2.473 (3) Å]. The Li atoms and the H atom in the symmetric hydrogen bond reside on twofold rotation axes and there is an inversion center at the mid‐point of the C—C bond of the ethylenediphosphonate ligand. 相似文献
80.
Wang Qing-Lun Zhao Bin Liao Dai-Zheng Yan Shi-Ping Cheng Peng Jiang Zong-Hui 《Transition Metal Chemistry》2003,28(3):326-330
The copper(II) complex Na2[Cu(pba)] · 6H2O has been synthesized and its structure determined. It consists of a novel two-dimensional network of [Cu(pba)]2– anions connected to each other through the sodium ion as a bridge. Spectroscopic and magnetic properties have been measured and a spin distribution calculation has been carried out with the GAUSSIAN-94. Theoretical calculations indicate the rather larger spin density on nitrogen atoms should be responsible for the satellite lines appearing beside the main hyperfine coupling signs of copper(II). The antiferromagnetic interaction may be due to the intermolecular interaction and/or different copper(II) ions through the Na+ bridge in the same layer. 相似文献