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Probe topology of complex networks by searching

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Probe topology of complex networks by searching

第二届全国复杂动态网络学术论坛

作者： Shi-Jie Yang department of physics, beijing normal university, beijing 100875, china

We carry out a comparative study on the problem for a walker searching on several typical complex *** search efficiency is evaluated for various *** no knowledge of the global properties of the underlying networks and the optimal path between any two given nodes,it is found that the best search strategy is the self-avoiding random walk. In return, topological information of the underlying networks may be drawn by comparing the results of the different search strategies.

关键词： complex network search strategy topology

Fuzzy cluster analysis of the provenance of ancient Yaozhou porcelain body

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Chinese Science Bulletin 2003年第1期48卷 27-30页

作者： LI Guoxia1, ZHAO Weijuan1, LI Rongwu2, XIE Jianzhong1, FENG Songlin3, FAN Dongyu3, ZHANG Ying3, CAI Zhifang3, ZHUO Zhenxi4 & GAO Zhengyao1 1. Faculty of Physical Engineering, Zhengzhou university, Zhengzhou 450052, china 2. department of physics, beijing normal university, beijing 100875, china 3. High Energy physics Institute, the Chinese Academy of Sciences, beijing 100080, china 4. Archaeology Research Institute, Shanxi Province, Xian 710000, china Correspondence should be addressed to Li Guoxia (e-mail: Liguoxia@ ***) Faculty of Physical Engineering Zhengzhou University Zhengzhou 450052 China department of physics Beijing Normal University Beijing 100875 China High Energy physics Institute Chinese Academy of Sciences Beijing 100080 China Archaeology Research Institute Shanxi Province Xi'an 710000 China

The technique of neutron activation analysis (NAA) has been employed to measure the content of 29 kinds of elements in the sample of Yaozhou porcelain bodies. Then a fuzzy cluster analysis has been conducted to the NAA data and a diagram of the dynamic fuzzy cluster analysis has been achieved. The results indicate that the batch of ancient Yaozhou porcelain bodies, which were of different overglaze color and were produced by different kilns during a period of over 800 years from the Tang Dynasty (618—907 A.D.) to the Yuan Dynasty (1271—1368 A.D.), has shared a stable and concentrated raw material source. Provenances of por-celain bodies from different times, though having their spe-cific independence, enjoy a close relationship and are not far from one another. Provenances of porcelain bodies made during the Tang Dynasty and the Five Dynasties (907—960 A.D.) are found to be closer to one another, while those of the Song (960—1279 A.D.) and the Jin Dynasty (1115—1234 A.D.) are comparatively concentrated in certain areas and are dif-ferent from those of the Tang Dynasty. Both the tri-colored glazed pottery made in Yaozhou kilns during the Tang Dy-nasty and the Yaozhou porcelain bodies of the Tang period are from the same provenance.

关键词：古代姚州瓷胎窑址粘土矿原料来源中子活化分布模糊聚类分析

Self-assembled growth of CeO2 nanostructures on r-cut sapphire

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Self-assembled growth of CeO2 nanostructures on r-cut sapphi...

2005年纳米和表面科学与技术全国会议

作者： J.C.Nie department of physics,beijing normal university,beijing 100875,china

CeO thin films have been largely stimulated because of their relatively highelectrical conductivity,chemical stability,transmission in the visible and infraredregions,and efficiency for absorbing ultraviolet *** fabrication and study ofnanostructured CeO thin films has been of interest by new phenomena arising from thereduction of dimensionality,from 3D in the bulk to 2D in the ultrathin films,1D in thenanostripes and/or 0D in the *** evidence of a cooperativeself-assembly process was obtained where high-temperature O annealing(1025℃)

关键词：

Microwave propagation in air drilling

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Petroleum Science 2010年第3期7卷 390-396页

作者： Meng Xiaofeng Chen Yijian Zhou Jing Meng Yingfeng physics department Beijing Normal University Beijing 100875 China State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum University Chengdu Sichuan 610500 China

This paper examines the feasibility in air drilling of transmitting down-hole signals by using microwaves. Firstly the basic theory of microwave propagation in the drill-pipe or casing was studied, including power loss, cutoff wavelength, and dust scattering. Theoretical analysis indicates that the microwave propagation distance in a cb214mm casing can easily reach 5,000 m. When the effect of dust particles is taken into account, the propagation distance decreases to 2,000 m. We conducted both laboratory experiments and field tests in casings commonly used in oil fields. The field tests show that the effective propagation distance of microwave in the casing is about 1,300 m. The experimental results do not match well with theoretical prediction, but are acceptable. In future commercial applications, by applying multiple relay amplifiers, the microwave propagation distance could be long enough for most drilling wells.

关键词： Microwave waveguide drill-pipe casing air drilling

胸腺T细胞由双阳到单阳分化发育的非线性模型

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生物化学与生物物理进展 2002年第1期29卷 69-73页

作者：张丽梅杜婵英北京师范大学物理学系北京100875

根据指令与随机相结合模型的理论 ,建立非线性数学模型 ,从理论上描述了胸腺内T细胞从双阳到单阳细胞的分化发育过程 .发现随着胸腺基质细胞 (TSCs)上MHCⅠ位点的增加 ,CD4+ 8+ 双阳胸腺细胞数量减少 ,CD4-8+ 单阳胸腺细胞数增加 ;随着C... 详细信息

根据指令与随机相结合模型的理论 ,建立非线性数学模型 ,从理论上描述了胸腺内T细胞从双阳到单阳细胞的分化发育过程 .发现随着胸腺基质细胞 (TSCs)上MHCⅠ位点的增加 ,CD4+ 8+ 双阳胸腺细胞数量减少 ,CD4-8+ 单阳胸腺细胞数增加 ;随着CD4+ 8+ 细胞与TSCs亲和力的增加 ,更多的双阳细胞进一步分化为单阳细胞 ,描述了胸腺基质细胞如何介导胸腺细胞从双阳向单阳分化发育的过程 .

关键词：胸腺细胞胸腺基质细胞胸腺选择 T细胞单阳细胞双阳细胞分化发育非线性模型

电磁直线加速动态黑洞时空中Dirac粒子的Hawking辐射

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物理学报 2003年第8期52卷 2096-2101页

作者：张靖仪赵峥北京师范大学物理系

研究了作直线加速运动的电磁黑洞视界面上Dirac粒子的Hawking辐射 .首先 ,构造对称化零标架 ,计算旋系数 ,导出Dirac方程 ,并对其进行化简 .然后 ,通过引入广义乌龟坐标 ,在视界面上将Dirac方程退耦 .利用Damour Ruffini方法 ,求出了温... 详细信息

研究了作直线加速运动的电磁黑洞视界面上Dirac粒子的Hawking辐射 .首先 ,构造对称化零标架 ,计算旋系数 ,导出Dirac方程 ,并对其进行化简 .然后 ,通过引入广义乌龟坐标 ,在视界面上将Dirac方程退耦 .利用Damour Ruffini方法 ,求出了温度以及热谱公式 ,并对所得结果进行了讨论 .

关键词：电磁直线加速动态黑洞时空 Dirac粒子 Hawking辐射 Damour-Ruffini方法温度热谱公式视界面

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一般球对称带电蒸发黑洞的温度

物理学报 2002年第5期51卷 1144-1148页

作者：宋太平姚国政北京师范大学物理学系

从视界附近的Klein Gordon方程出发 ,准确地定出了一般球对称带电蒸发黑洞的Hawking温度和辐射谱 ,同时计算出事件视界方程 .所得结果与用零曲面方程得到的结果一致 .

关键词：一般球对称带电蒸发黑洞温度视界辐射谱热力学

Analyzing chaotic systems by network characters

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Analyzing chaotic systems by network characters

第三届全国复杂动态网络学术论坛

作者： Xiaojuan Ma, Yan Wong, Zhigang Zheng physics department of beijing normal university, beijing, 100875, china

＜正＞In this paper, complex networks are constructed from the time series of chaotic systems, with different definitions of a node in the network. By analyzing the characters of the corresponding networks, we can ide... 详细信息

关键词： chaos networks critical threshold degree distribution weight distribution

Bell States and Two-Qubit Logic Gate with Superconducting Charge Qubits Coupling to a Nanomechanical Resonator

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Communications in Theoretical physics 2007年第12期48卷 999-1002页

作者： LIAO Jie-Qiao~1 and WANG Xin-Wen~(2,3)~1 department of physics,Hunan normal university,Changsha 410081,china~2 department of physics,beijing normal university,beijing 100875,china~3 department of Electronic Engineering and physics,Hunan university of Science and Engineering,Yongzhou 425100,china department of physics Hunan Normal University department of physics Beijing Normal University department of Electronic Engineering and physics Hunan University of Science and Engineering

We propose a scheme for generating Bell states involving two SQUID-based charge qubits by coupling themto a nanomechanical *** also show that it is possible to implement a two-qubit logic gate between the twocharge qu... 详细信息

关键词： Bell states superconducting charge qubit two-qubit logic gate nanomechanical resonator