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Let G be a graph with vertex set V(G) and edge set E(G). A labeling f : V(G) →Z2 induces an edge labeling f*: E(G) → Z2 defined by f*(xy) = f(x) + f(y), for each edge xy ∈ E(G). For i ∈ Z2, let vf(i) = |{v ∈ V(G) : f(v) = i}| and ef(i) = |{e ∈ E(G) : f*(e) =i}|. A labeling f of a graph G is said to be friendly if |vf(0)- vf(1)| ≤ 1. The friendly index set of the graph G, denoted FI(G), is defined as {|ef(0)- ef(1)|: the vertex labeling f is friendly}. This is a generalization of graph cordiality. We investigate the friendly index sets of cyclic silicates CS(n, m). 相似文献
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以马蹄金素[N-(N-苯甲酰基-L-苯丙氨酰基)-O-乙酰基-L-苯丙氨醇,MTS]为先导化合物,设计并合成了16个杂环取代的马蹄金素衍生物,其结构经NMR,ESI-MS和元素分析确证.以HepG2 2.2.15细胞为乙肝病毒(HBV)载体,对合成的马蹄金素衍生物进行了抗HBV活性测试.实验结果表明,在测试浓度范围内,化合物5b(IC50=8.20μg/L,SI=10.26),5g(IC50=5.58μg/L,SI=22.78)和5i(IC50=5.07μg/L,SI=16.67)的抗HBV活性较强;在8μg/mL的浓度下,其抑制率分别为56.57%,67.06%和66.83%. 相似文献
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Evolution map from TD-SCDMA to FuTURE B3G TDD 总被引:6,自引:0,他引:6
Guangyi Liu Jianhua Zhang Ping Zhang Ying Wang Xiantao Liu Shuang Li 《Communications Magazine, IEEE》2006,44(3):54-61
The rapid growth of mobile applications in recent years has created a need for wideband wireless communication. The only predictable trend is that data-rate and QoS requirements will increase rapidly. This demand is pushing time-division-synchronous code-division multiple access (TD-SCDMA) to evolve in order to provide higher and higher data rates. This article presents the evolution map from TD-SCDMA to future terrestrial universal radio environment (FuTURE) TDD in China. The evolution includes four phases: low chip rate (LCR), high-speed downlink/uplink packet access (HSxPA)/TD-SCDMA EV 1x, long-term evolution (LTE) TDD, and FuTURE beyond 3G TDD. The main features of each phase are described in detail. By introducing the new technologies into the system step by step, for example, multiple input and multiple output (MIMO), orthogonal frequency-division multiplexing (OFDM), TD-SCDMA system can evolve to FuTURE B3G TDD smoothly, and provide high-data-rate services with low cost, low latency, and improved coverage and capacity. 相似文献
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Guangyi?Gu Bing?Dai Xunlei?Ding Jinlong?YangEmail author 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2004,29(1):27-31
Hybrid density functional calculations are performed to study the structural and electronic properties of neutral, anionic and cationic Y3O clusters. The most stable structures of these clusters are found to be triply bridging oxygen atom structures with CS symmetry. The ground states of Y3O, Y3O- and Y3O + are doublet (2A), triplet (3A) and singlet (1A), respectively. The calculated electron affinities and ionization potentials are in good agreement with the available experimental data. Time-dependent density functional theory is used to calculate the low-lying excited states. A theoretical assignment for the features in the experimental photoelectron spectra is given.Received: 5 November 2003, Published online: 20 January 2004PACS:
36.40.Mr Spectroscopy and geometrical structure of clusters - 31.15.Ew Density-functional theory - 34.50.Gb Electronic excitation and ionization of molecules; intermediate molecular states (including lifetimes, state mixing, etc.) 相似文献
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本文根据美声演唱的具体需要,在分析了室内混响时间测量方式的基础上,以VRAS(可变室内声学系统)为例探究了室内声学系统建设的可行性及重要意义。 相似文献
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Based on the recognition requirement to suppress types of noise created in the conversion process of handwritten characters
into binary patterns in our optical character recognition, an algorithm of processing digital character noise is presented.
The software and hardware of the algorithm is described. 相似文献
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