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光磁共振实验测量方法研究

陕西师范大学学报（自然科学版） 2001年第4期29卷 118-119页

作者：隋峰卢永智陕西师范大学物理学与信息技术学院陕西西安710062

从理论上对光磁共振实验的常规方法进行了分析 ,讨论了常规方法中影响测量精度的因素 ,提出了借助示波器及指南针调节扫描场幅度的改进措施 .改进后的实验可以避免对水平磁场。

关键词：光磁共振实验光抽运朗德因子测量原理铷原子偏激化测量方法

外磁场中Hubbard系统的表面传导电子能和自旋波

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陕西师范大学学报（自然科学版） 2007年第S2期35卷 46-48页

作者：赵新军张军伊犁师范学院物理与电子信息学院新疆伊宁835000 新疆大学物理科学与技术学院新疆乌鲁木齐830046

讨论了在外磁场中Hubbard系统的表面传导电子能和自旋波,发现在外磁场中Hubbard系统表面传导电子能明显不同于系统内部传导电子能,这正好可以解释在固体表面其特性是有异常的.对于自旋波谱的研究发现,由于外磁场的介入,自旋波谱不仅与... 详细信息

讨论了在外磁场中Hubbard系统的表面传导电子能和自旋波,发现在外磁场中Hubbard系统表面传导电子能明显不同于系统内部传导电子能,这正好可以解释在固体表面其特性是有异常的.对于自旋波谱的研究发现,由于外磁场的介入,自旋波谱不仅与自旋向上和向下的电子数有关,而且由于外磁场的存在而变得较为复杂.

关键词： Hubbard模型格林函数表面传导电子能自旋波

Prediction of Earthquake in Yunnan Region Based on the AHC over Sampling

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Prediction of Earthquake in Yunnan Region Based on the AHC o...

Research on the Security in Wireless Sensor Network

2010 Chinese Control and Decision Conference

作者： Kai Tan,Xiushan Cai college of mathematics,physics and information Engineering,Zhejiang Normal university,Jinhua,321004,china

The data of earthquake of magnitude 3.5 or greater that happened during the 1970 and 2008 in Yunnan region (22 degrees and 28 degrees north,98 degrees and 104 degrees east) were compiled and analyzed in this *** calculating the seismicity indicators and constructing the initial data set,AHC over sampling method was used on the imbalanced *** small earthquakes and large ones during the 1999 and 2008 were predicted and verified with the support vector machines(SVM) which contains different error *** result performs well,and it provides a new way for the earthquake prediction.

关键词： Earthquake prediction Biased support vector machines Over sampling Seismicity indicators

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Research on the Security in Wireless Sensor Network

互联网上三种外文期刊数据库的文献检索比较研究

中国通信学会第五届学术年会

作者： Wang Jianqiu1,2 Lang Weimin3 Ji Yinghua1 (1 college of physics and Communication Electronics, Jiangxi Normal university, Nanchang, 330027, china 2 college of Electronic and information Engineering,Wuhan Institute of technology, Wuhan, 430074, china 3 PLA Communication Commands Academy, Wuhan, 430010, china)

As sensor networks edge closer towards wide-spread deployment, security issues become a central concern. Typical sensors possess limited computation, energy, computation, memory resources and they are always deployed in a harsh, unattended or hostile environment, so the security issues posed by sensor networks represent a rich and challenging field of research problems. In this paper, we probe into various security requirements with regard to Wireless Sensor Network（WSN）. Furthermore, we analyze status quo of the security in WSN from three aspects: key management, identity authentication as well as attacks and countermeasures. In conclusion, we point out its development direction based on the analysis and remark of problems remaining unsolved in WSN.

关键词： Sensor Network Security Key Management Authentication Attacks and Countermeasures

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图书情报工作 2003年第5期47卷 77-79,86页

作者：章亚娟浙江师范大学数理与信息科学学院金华321004

对KLUIWER电子期刊数据库、EBSCO全文期刊数据库和维普库中的外文科技期刊数据库的收录范围、标引质量、检索功能、输出形式等进行比较分析后,指出它们各自的使用特点与不足,并提出在使用这些数据库时需注意的问题。

关键词：互联网外文期刊数据库文献检索比较研究收录范围标引质量检索功能

Growing Area Determination of Tremella Fuciformis Using Visible and Near-Infrared Spectroscopy

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Growing Area Determination of Tremella Fuciformis Using Visi...

Structure, spin reorientation and Mssbauer effect studies of Tb0.3Dy0.7(Fe1-xAlx)1.95 alloys

2010 3rd IEEE International Conference on Computer science and information technology—ICCSIT 2010

作者： Xiaojing Chen Meng Xu Xiangou Zhu college of physics and Electronic information Engineering Wenzhou university Wenzhou 325027 china

Visible and near infrared （NIR） spectroscopy was utilized to determine the growing areas of Tremella *** component analysis （PCA） obtained the cluster plot which shows the difficulty to determine the growing area by the first three principal ***-square support vector machine （LS-SVM） was used to establish the calibration *** projections algorithm （SPA） was applied to select the effective variables from the full-spectrum （FS） which have 675 spectra *** eleven variables were *** variables based LS-SVM model obtain 100% determination correct *** was proved that SPA was an effective algorithm for spectra variable *** a conclusion,Vis-NIR spectroscopy could be used to determine the growing areas of Tremella fuciformis fast and accurately.

关键词： Visible and near infrared Principal component analysis Least-square support vector machine Tremella fuciformis Successive projections algorithm

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science china(physics,Mechanics & Astronomy) 2006年第2期Mechanics & Astronomy) .卷 149-157页

作者： ZHENG Xiaoping1,2,4, ZHANG Peifeng1,3, FAN Duowang1, LI Fashen3 & HAO Yuan41. Key Laboratory of Opto-Electronic technology and Intelligent Control, Ministry of Education, Lanzhou Jiaotong university, Lanzhou 730070, china 2. Institute of Electronic information science and technology,Lanzhou Teachers college, Lanzhou 730070, china 3. Key laboratory for Magnetism and Magnetic Materials, Ministry of Education, Lanzhou university, Lan-zhou 730000, china 4. State Key Lab. of Advanced Non-Ferrous Materials, Gansu Province, Lanzhou university of technology, Lanzhou 730050, china

The effect of Al substitution for Fe on crystal structure, magnetostriction and spontaneous magnetostriction, anisotropy and spin reorientation of a series of polycrys-talline Tb0.3Dy0.7(Fe1?xAlx)1.95 alloys (x = 0, 0.05, 0.1, 0.15, 0.20, 0.25, 0.30, 0.35) at room temperature and 77 K was investigated systematically. It was found that the primary phase of Tb0.3Dy0.7(Fe1?xAlx)1.95 is the MgCu2-type cubic Laves phase structure when x 3Dy0.7(Fe1?xAlx)1.95 increases approximately and monotonically with the increase of x. The substitution of Al leads to the fact that the magnetostriction λ inceases slightly in a low magnetic field (H ≤ 40 kA/m), but decreases sharply and is easily close to saturation in a high applied field as x increases, showing that a small amount of Al substitution is beneficial to a decrease in the magnetocrystalline anisotropy. It was also found that the spontaneous magnetostriction λ111 decreases greatly with x in-creasing. The analysis of the M?ssbauer spectra indicated that the easy magnetization direction in the {110} plane deviates slightly from the main axis of symmetry with the changes of composition and temperature, namely spin reorientation. A small amount of non-magnetic phase exists for x = 0.15 in Tb0.3Dy0.7(Fe1?xAlx)1.95 alloys and the alloys be-come paramagnetic for x > 0.15 at room temperture, but at 77 K the alloys still remain magnetic phase even for x = 0.2. At room temperature and 77 K, the hyperfine field de-creases and the isomer shifts increase with Al concentration increasing.

关键词： magnetostriction cubic Laves phase spin reorientation M?ssbauer.

ALMOST AUTOMORPHIC MILD SOLUTIONS TO SOME FRACTIONAL DELAY DIFFERENTIAL EQUATIONS

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Annals of Differential Equations 2012年第4期28卷 412-416页

作者： Xiliang Li 1,Fenglong Qu 2,Yuliang Han 1(1.college of math.and information sciences,Shandong Institute of Business and technology,Yantai 264005,Shandong 2.School of math.and informational science,Yantai university,Yantai 264005,Shandong)

In this paper,a new and general existence and uniqueness theorem of almost automorphic mild solutions is obtained for some fractional delay differential equations,using sectorial operators and the Banach contraction p... 详细信息

关键词： sectorial operator almost automorphy fractional delay differential equation

Effects of the 3d transition metal doping on the structural, electronic, and magnetic properties of BeO nanotubes

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Chinese physics B 2014年第1期23卷 357-362页

作者：张建民宋婉婷李欢欢徐可为 JiVincent college of physics and information technology Shaanxi Normal University Xi 'an 710062 China State Key Laboratory for Mechanical Behavior of Materials Xi'an Jiaotong University Xi' an 710049 China ICMMO/LEMHE Universitd Paris-Sud 1191405 Orsay Cedex France

First-principles calculations have been performed on the structural, electronic, and magnetic properties of seven 3d transition-metal （TM） impurities （V, Cr, Mn, Fe, Co, Ni, and Cu） doped armchair （5,5） and zigzag （8,0） beryllium oxide nanotubes （BeONTs）. The results show that there exists a structural distortion around the 3d TM impurities with respect to the pristine BeONTs. The magnetic moment increases for V- and Cr-doped BeONTs and reaches a maximum for Mn-doped BeONT, and then decreases for Fe-, Co-, Ni-, and Cu-doped BeONTs successively, consistent with the predicted trend of Hund＇s rule to maximize the magnetic moments of the doped TM ions. However, the values of the magnetic moments are smaller than the predicted values of Hund＇s rule due to the strong hybridization between the 2p orbitals of the near O and Be ions of BeONTs and the 3d orbitals of the TM ions. Furthermore, the V-, Co-, and Ni-doped （5,5） and （8,0） BeONTs with half-metal ferromagnetism and thus 100% spin polarization character are good candidates for spintronic applications.

关键词： BeO nanotubes,transition-metal atoms half-metal ferromagnets first-principles calculation