左-右手系材料界面上的表面波
作者:
蒋练军;熊翠秀;金辉霞
期刊:
湖南城市学院学报(自然科学版) ,2009年18(2):48-51 ISSN:1672-7304
作者机构:
湖南城市学院,物理与电子信息工程系,湖南,益阳,413000;[蒋练军; 熊翠秀; 金辉霞] 湖南城市学院
关键词:
左手材料;右手材料;非线性;表面波
摘要:
利用严格的电磁理论证明2种偏振入射都能在各向同性的负折射材料与正折射材料界面上激发表面波,并推导出了相应表面波的传播波矢和激发条件.针对电磁波在非线性左手系材料中的传播性质,研究左、右手系材料界面上非线性TE表面波的传播行为,分析表明:2种界面上的非线性TE表面波均存在频率通带和禁带.
语种:
中文
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对单模光场与二能级原子相互作用系统量子场熵演化的再研究
作者:
姚映波;唐炳
期刊:
湖南城市学院学报(自然科学版) ,2009年18(3):47-49 ISSN:1672-7304
作者机构:
湖南城市学院,物理与电子信息工程系,湖南,益阳,413000;[唐炳; 姚映波] 湖南城市学院
关键词:
单模光场;二能级原子;相互作用;量子场熵演化
摘要:
利用全量子理论,研究了单模光场与二能级原子相互作用系统的量子场熵演化规律.利用MATLAB进行数值计算,讨论了光场的平均光子数<n>、光场-原子之间的耦合系数g对量子场熵演化规律的影响,得到了相应的结论.
语种:
中文
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Jacobian函数行列式推导热力学关系的统一方法
作者:
张光富;熊洁;邓英
期刊:
考试周刊 ,2008年(6):192-194 ISSN:1673-8918
作者机构:
湖南城市学院物电系;湖南城市学院物电系 湖南益阳;湖南益阳
关键词:
雅可比函数;热力学函数;热力学关系
摘要:
本方利用雅可比函数行列式统一导出了简单可压缩系统的所有热力学关系式,同时指出了雅可比行列式推导热力学关系式的一般方法。它的优点是:不需要前提条件,只需利用雅可比函数行列式和麦克斯韦关系式进行简单的运算,便可推导所有的热力学关系式。
语种:
中文
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图书馆知识管理本质论析
作者:
汤利光
期刊:
城市学刊 ,2008年29(2):107-110 ISSN:2096-059X
作者机构:
武汉大学,信息管理学院,武汉,430072;湖南城市学院,网络中心,湖南,益阳,413000;[汤利光] 武汉大学
关键词:
图书馆;知识管理;本质
摘要:
图书馆知识管理已成为当代图书馆学研究的重要内容.图书馆知识管理的本质是客观知识信息的组织与传播,图书馆学研究应把握好图书馆知识管理的"度",否则又将陷入新的误区.
语种:
中文
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基于统计分析对交通信息集成的优化
作者:
阳王东;何焕民;祝青
期刊:
交通运输系统工程与信息 ,2008年8(4):114-118 ISSN:1009-6744
通讯作者:
Yang, W.-D.(yangwangdong@163.com)
作者机构:
[祝青; 阳王东] Department of Computer Science and Technology, Hunan City University, Yiyang 413000, China;[何焕民] Shan Tou Lin Baixin Science and Techology School, Shantou 515041, China
通讯机构:
Department of Computer Science and Technology, Hunan City University, China
关键词:
消息;信息集成;区间估计;通道
摘要:
交通信息集成能够综合分析和利用各种交通信息系统所产生和采集的数据,从而实现对城市交通的综合管理和统一调度.但由于交通信息数据量大且有较强的实时性,并且不同的交通信息对传输性能的要求也不尽相同,因此交通信息传输的QoS要求尤为重要.基于统计分析对交通信息集成的优化是在利用消息总线实现对数据集成,对实时交通信息的传输延时和信息之间的传输相干性进行统计分析,来获取交通信息传输的定量特性,为交通信息传输过程中的消息传输通道、缓冲队列和时间限制等参数设置提供依据,从而优化交通信息的集成,有助于提高实时交通信息的响应时间和处理效率.
语种:
中文
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星风和柱形喷流对伽玛射线暴余辉的联合作用
作者:
蒋练军;熊翠秀
期刊:
湖南师范大学自然科学学报 ,2008年31(02):59-63 ISSN:2096-5281
作者机构:
湖南城市学院物理与电子信息工程系,中国益阳,413000
关键词:
柱形喷流;伽玛射线暴;激波;统一动力学模型
摘要:
假设介质的数密度随激波半径呈幂律分布:next∝R-K.基于统一动力学模型和柱形喷流模型,用数值计算方法系统计算了K=2(即星风环境下)的动力学量随时间的演化,并计算了光学余辉和射电余辉随时间的演化,得出了相关的规律.
语种:
中文
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Rectangular Array Pattern Synthesis with Simple Method
作者:
Huang, Longyang* ;Cheng, En;Li, Mengxing
期刊:
International Conference on Signal Processing Proceedings, ICSP ,2008年:183-186
通讯作者:
Huang, Longyang
作者机构:
[Huang, Longyang; Cheng, En] Xiamen Univ, Minist Educ, Key Lab Underwater Acoust Commun & Marine Informa, Xiamen 361005, Peoples R China.;[Li, Mengxing] Hunan City Univ, Dept Phys & Telecommun, Yiyang 413000, Hunan, Peoples R China.
通讯机构:
[Huang, Longyang] X;Xiamen Univ, Minist Educ, Key Lab Underwater Acoust Commun & Marine Informa, Xiamen 361005, Peoples R China.
会议名称:
9th International Conference on Signal Processing(第九届国际信号处理学术会议)(ICSP'08)
会议时间:
2008-10-26
会议地点:
北京
会议论文集名称:
9th International Conference on Signal Processing(第九届国际信号处理学术会议)(ICSP'08)论文集
摘要:
A simple method for rectangular array pattern synthesis, which combines convolution of two perpendicular linear arrays with orthogonal approach for each linear array synthesis, is proposed. Because beam patterns derive from Fourier transforms of distributions in space, the distribution to produce the product of two simpler patterns is the convolution of the simpler distributions. A desired rectangular array pattern can be synthesized through multiplication of two perpendicular linear array patterns. At the same time, the relatively simple and general orthogonal method is applied for linear array synthesis to reduce the amount of computation further. ©2008 IEEE.
语种:
英文
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An Improved Mutual Authentication Scheme in Multi-Hop WiMax Network
作者:
Jin, Huixia* ;Tu, Li;Yang, Gelan;Yang, Yatao
期刊:
Proceedings of the 2008 International Conference on Computer and Electrical Engineering, ICCEE 2008 ,2008年:296-299
通讯作者:
Jin, Huixia
作者机构:
[Jin, Huixia] Hunan City Univ, Dept Phys & Telecom Engn, Yiyang 413008, Peoples R China.;[Yang, Gelan; Tu, Li] Hunan City Univ, Dept Comp Sci, Yiyang 413008, Peoples R China.;[Yang, Yatao] Beijing Elect Sci & Technol Inst, Beijing 100070, Peoples R China.
通讯机构:
[Jin, Huixia] H;Hunan City Univ, Dept Phys & Telecom Engn, Yiyang 413008, Peoples R China.
摘要:
The mutual authentication mechanism in the IEEE802.16e can avoid the man-in-middle attack, and can protect the multi-hop WiMax security in efficiency. An improved X.509 certificate based on ECC algorithm is designed, then an enhanced mutual authentication flow was proposed in this paper, which enhances the security and working efficiency of the mutual authentication in multi-hop WiMax system. The proposed scheme heightens the security and practicability of WiMax system, which has better referenced value to the improvement of IEEE 802.16e standards.
语种:
英文
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Optimal Model for Energy-Efficient Clustering in Wireless Sensor Networks Using Global Simulated Annealing Genetic Algorithm
作者:
Zhang, Jianming* ;Lin, Yaping;Zhou, Cuihong;Ouyang, Jingcheng
期刊:
2008 INTERNATIONAL SYMPOSIUM ON INTELLIGENT INFORMATION TECHNOLOGY APPLICATION WORKSHOP: IITA 2008 WORKSHOPS, PROCEEDINGS ,2008年:656-660
通讯作者:
Zhang, Jianming
作者机构:
[Zhang, Jianming; Ouyang, Jingcheng; Lin, Yaping] Hunan Univ, Coll Comp & Commun, Changsha 410082, Hunan, Peoples R China.;[Zhou, Cuihong; Zhang, Jianming] Hunan City Univ, Dept Comp Sci, Yiyang 413000, Hunan, Peoples R China.;[Lin, Yaping] Hunan Univ, Coll Software, Changsha 410082, Hunan, Peoples R China.
通讯机构:
[Zhang, Jianming] H;Hunan Univ, Coll Comp & Commun, Changsha 410082, Hunan, Peoples R China.
会议名称:
2nd International Symposium on Intelligent Information Technology Application
会议时间:
DEC 21-22, 2008
会议地点:
Shanghai, PEOPLES R CHINA
会议主办单位:
[Zhang, Jianming;Lin, Yaping;Ouyang, Jingcheng] Hunan Univ, Coll Comp & Commun, Changsha 410082, Hunan, Peoples R China.^[Zhang, Jianming;Zhou, Cuihong] Hunan City Univ, Dept Comp Sci, Yiyang 413000, Hunan, Peoples R China.^[Lin, Yaping] Hunan Univ, Coll Software, Changsha 410082, Hunan, Peoples R China.
关键词:
energy-efficient clustering;global simulated annealing genetic algorithm;wireless sensor networks
摘要:
Since the operations of sensors in wireless sensor networks (WSNs) mainly rely on battery energy, energy consumption becomes an important issue. In this paper, we use a global simulated annealing genetic algorithm (GSAGA) to create energy efficient clusters for routing in WSNs. The simulation results show that the proposed GSAGA algorithm has higher efficiency and can achieve better network lifetime and data delivery at the base station than a few existing cluster-based routing protocols.
语种:
英文
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A Novel Roaming Hand-off Authentication Scheme in Multi-Hop Wireless Network
作者:
Tu, Li* ;Jin, Huixia;Yang, Gelan;Yang, Yatao
期刊:
Proceedings of the 2008 International Conference on Computer and Electrical Engineering, ICCEE 2008 ,2008年:308-311
通讯作者:
Tu, Li
作者机构:
[Yang, Gelan; Tu, Li] Hunan City Univ, Dept Comp Sci, Yiyang 413008, Peoples R China.;[Jin, Huixia] Hunan City Univ, Dept Phys & Telecom Engn, Yiyang 413008, Peoples R China.;[Yang, Yatao] Beijing Elect Sci & Technol Inst, Beijing 100070, Peoples R China.
通讯机构:
[Tu, Li] H;Hunan City Univ, Dept Comp Sci, Yiyang 413008, Peoples R China.
摘要:
It can be inescapable to solve the issue of hand-off authentication between the different trusted domains in the future wireless network development. By adopting threshold scheme, distributed hand-off authentication secure communication model is designed, then the process of cross certificate being issued and the steps of roaming hand-off authentication from node leaving former network to joining in new network are described and analyzed. Without CA (Certificate Authority), a new roaming hand-off authentication scheme between the different trusted domains in multi-hop wireless network is proposed, an efficient method can be provided for node's roaming hand-off and secure communication, the attack of single node being captured also can be avoided, which has better flexibility and security, and has important referenced value for the future application of wireless multi-hop network. ©2008 IEEE.
语种:
英文
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Generation of dispersion-free millimeter wave signals by double sideband modulation and vestigial sideband filtering techniques
作者:
Xu, Lan Yun* ;Yu, Jian Guo;Xu, Hong Yun
期刊:
Microwave and Optical Technology Letters ,2008年50(8):2158-2161 ISSN:0895-2477
通讯作者:
Xu, Lan Yun
作者机构:
[Xu, Lan Yun] Hunan City Univ, Dept Phys & Elect Engn, Yiyang 413000, Hunan, Peoples R China.;[Yu, Jian Guo] Beijing No Fiberhome Technol Co Ltd, Beijing 100088, Peoples R China.;[Xu, Hong Yun] S China Univ Technol, Sch Comp Sci & Engn, Guangzhou 510640, Peoples R China.
通讯机构:
[Xu, Lan Yun] H;Hunan City Univ, Dept Phys & Elect Engn, Yiyang 413000, Hunan, Peoples R China.
关键词:
optical mm-wave generation;vestigial sideband filtering;radio-over-fiber;power penalty
摘要:
Fiber dispersion in standard single mode fiber (SSMF) limits the maximum delivery distance for the optical millimeter (mm)-wave signals generated by double sideband modulation and vestigial sideband filtering. We propose and experimentally demonstrate a novel scheme to generate mm-wave signals without dispersion limitation. The power penalty for 2.5-Gbit/s mm-wave signals carried by 40-GHz radio-frequency after transmission over 80-km SSMF is smaller than 0.5 dB. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 2158–2161, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23605
语种:
英文
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Photon-Assisted Electron Transport for a Λ-shaped Carbon Nanotube Junction
作者:
Jiang Lian-Jun;Liao Wen-Hu;Zhou Guang-Hui*
期刊:
中国物理快报:英文版 ,2008年25(5):1836-1839 ISSN:0256-307X
通讯作者:
Zhou Guang-Hui
作者机构:
[Zhou Guang-Hui; Liao Wen-Hu; Jiang Lian-Jun] Hunan Normal Univ, Dept Phys, Changsha 410081, Peoples R China.;[Jiang Lian-Jun] Hunan City Coll, Dept Phys & Elect Engn, Yiyang 413000, Peoples R China.
通讯机构:
[Zhou Guang-Hui] H;Hunan Normal Univ, Dept Phys, Changsha 410081, Peoples R China.
关键词:
QUANTUM-DOT;SINGLE;GRAPHENE;VICES;the time-averaged
摘要:
We theoretically study the electron transport properties for two coupled single-walled carbon nanotube quantum dots connected to metallic electrodes under the irradiation of an external electromagnetic field at low temperatures. Using the standard nonequilibrium Green's function techniques, we examine the time-averaged transmission coefficient and linear conductance. It is shown that by some numerical examples, the photon-assisted inter-dot coupling causes Fano resonance and the conductance of the system is sensitive to the external field parameters. The transport dependence on the external field parameters may be used to detect the high-frequency microwave irradiation.
语种:
英文
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一种基于服务空间的服务提供模型
作者:
阳王东;吴宏斌;祝青
期刊:
小型微型计算机系统 ,2008年29(11):2004-2011 ISSN:1000-1220
作者机构:
[阳王东] 中南大学,信息科学与工程学院,湖南,长沙,410008;[阳王东; 祝青; 吴宏斌] 湖南城市学院,计算机科学技术系,湖南,益阳,413000
关键词:
服务;代理;面向服务架构
摘要:
SOA的应用日益广泛,构建SOA的工具和平台也日益丰富.而集中式SOA架构会增加成本,限制资源的再利用,降低系统的灵活性,并且有可能导致成本高昂的系统瓶颈.基于服务空间的服务提供模型是一种分布式SOA架构,他通过构建和部署服务空间来分步骤渐进式地实施SOA,并且利用服务空间可以整合已有的系统和资源而提供服务功能,并不需要改变原有系统的运行环境,并且服务空间之间是独立的,不需要一个共有的Hub、Bus或中央服务器.这样不但使得已有(或新的)IT资产可以得到更好重用,而且避免新增加昂贵的服务器和中间件软件,因此,能够更好地满足基于SOA架构的应用程序对各项技术和成本的要求.
语种:
中文
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负折射系统中的光学补偿效应
作者:
饶坚
期刊:
湖南城市学院学报(自然科学版) ,2008年17(4):34-37 ISSN:1672-7304
作者机构:
湖南城市学院,物理与电子工程系,湖南,益阳,413000;湖南大学,材料科学与工程学院,长沙,410082;[饶坚] 湖南城市学院
关键词:
坐标变换;补偿效应;负折射
摘要:
利用Pendry提出的坐标变换方法,研究了负折射材料构成的旋转椭球体、旋转抛物体和双球面系统中的光学补偿效应,发现系统的介电常数和磁导率为某一定值,该系统就具有相应的光学补偿效应,即从系统中某一点所发出的光线可传播至系统中另一点,该点的光场和光源完全一致.特别是双球面系统,其介电常数和磁导率可设计为一个标量,大大降低了技术上的难度,从而可能应用于某些实际光学系统.
语种:
中文
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Negative specific heat, phase transition and particles spilling from a potential well
作者:
Rao, J.;Liu, Q. H.* ;Liu, T. G.;Li, L. X.
期刊:
Annals of Physics ,2008年323(6):1415-1423 ISSN:0003-4916
通讯作者:
Liu, Q. H.
作者机构:
[Liu, T. G.; Rao, J.; Liu, Q. H.; Li, L. X.] Hunan Univ, Sch Theoret Phys, Changsha 410082, Hunan, Peoples R China.;[Liu, T. G.; Rao, J.; Liu, Q. H.; Li, L. X.] Hunan Univ, Dept Appl Phys, Changsha 410082, Hunan, Peoples R China.;[Rao, J.] Hunan City Univ, Dept Phys & Elect Engn, Yiyang 413049, Peoples R China.
通讯机构:
[Liu, Q. H.] H;Hunan Univ, Sch Theoret Phys, Changsha 410082, Hunan, Peoples R China.
关键词:
05.20.-y;36.40.Ei;Classical statistical mechanics;Negative specific heat;Phase transition for finite number of particles
摘要:
For a finite number of noninteracting particles in a box with a potential well in the center, the microcanonical kinetic energy in dependence on the total energy as it is negative can be classified into three categories. The first exhibits a monotonical rise and the specific heat is positive. The second shows a diminishing sawtooth wave with a global rise. The last corresponds to the extreme case and takes the regular sawtooth wave form. The sawtooth wave portion associates periodically a kinetic energy fall in spite of an increase of the total energy; and we attribute to such a fall the negative specific heat. The phase transition can be defined when the relatively dense particle state in the well and relatively dilute particle state in the rest volume of the box coexist, and the appearance of the negative specific heat is sufficient but not necessary for the onset of the phase transition. © 2007 Elsevier Inc. All rights reserved.
语种:
英文
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含负折射率介质的光子隧道显微镜的分析
作者:
熊翠秀;蒋练军
期刊:
湖南城市学院学报(自然科学版) ,2008年(1):34-37 ISSN:1672-7304
作者机构:
湖南城市学院物理与电子信息工程系;湖南城市学院物理与电子信息工程系 湖南益阳413000
关键词:
左手性物质;光子隧道效应;传输矩阵
摘要:
利用多层结构的传输矩阵,分析了光子隧道显微镜中LHM层增强光子隧道效应的可能性,为左手性物质(LHMs)的应用提供了一种新思路.
语种:
中文
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左-右手介质层中的光子隧道效应的分析
作者:
蒋练军;金辉霞;熊翠秀
期刊:
海南大学学报(自然科学版) ,2008年26(2):126-130 ISSN:1004-1729
作者机构:
湖南城市学院物理与电子信息工程系,湖南,益阳,413000;[蒋练军; 熊翠秀; 金辉霞] 湖南城市学院
关键词:
左-右手介质;隧道效应;瞬逝波;折射率
摘要:
分析了TE波入射到包含左手介质的4层平板层的结构中的现象,若不考虑介质的损耗,当隧道层中左手介质层和右手介质层的厚度、折射率相匹配时,电磁波在这样的结构中传播能产生全透射,并且与只包含右手介质的光子隧道相比较,光子在这样的结构中能传播更远的距离(约几个波长).
语种:
中文
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有线无线网络拥塞控制技术最新研究进展
作者:
何建新;王建新
期刊:
电脑与信息技术 ,2008年16(2):5-7+13 ISSN:1005-1228
作者机构:
中南大学信息科学与工程学院,湖南,长沙,410075;湖南城市学院计算枳科学系,湖南,益阳,413000;[何建新; 王建新] 中南大学
关键词:
网络;拥塞控制;研究;进展
摘要:
文章阐述了资源供需关系与网络拥塞的影响,分析了网络拥塞的原因及拥塞控制算法性能评价方法,并分别对目前有线无线网络使用的各种拥塞控制算法进行了比较分析,指出了存在的缺陷和取得的最新研究进展。最后,根据目前最新研究情况,提出了把控制与优化理论引入到网络拥塞控制中的思路,进一步明确了研究趋势和发展方向。
语种:
中文
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一种基于能量检测及用户合作的协作感知技术
作者:
周来秀;贺建军;邓曙光;胡赛纯
期刊:
湖南城市学院学报(自然科学版) ,2007年16(2):50-53 ISSN:1672-7304
作者机构:
中南大学,信息科学与工程学院,长沙,410083;湖南城市学院,物理与电子信息工程系,湖南,益阳,413000;[周来秀; 贺建军] 中南大学;[胡赛纯; 邓曙光] 湖南城市学院
关键词:
感知无线电;频谱感知;能量检测;协作感知
摘要:
随着无线技术的飞速发展,频谱缺乏已经成为一个非常严重的问题.感知无线电技术能有效解决频谱紧张的现状.介绍了感知无线电概念及其内涵,然后介绍了检测频谱空穴的方法.为提高检测概率、降低设备复杂度及计算复杂度,将UWB与感知无线电结合,提出了基于能量检测及用户合作(EDAUC)的协作感知方法.仿真和分析表明:该方法能有效提高检测频谱空穴的概率.
语种:
中文
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On the similarity of DNA primary sequences based on 5-D representation
作者:
Liao, Bo* ;Li, Renfa;Zhu, Wen;Xiang, Xuyu
期刊:
Journal of Mathematical Chemistry ,2007年42(1):47-57 ISSN:0259-9791
通讯作者:
Liao, Bo
作者机构:
[Liao, Bo] Hunan Univ, Lab Embedded Comp & Syst, Sch Comp & Commun, Changsha 410082, Peoples R China.;Hunan City Univ, Dept Comp Sci, Yiyang 413000, Peoples R China.
通讯机构:
[Liao, Bo] H;Hunan Univ, Lab Embedded Comp & Syst, Sch Comp & Commun, Changsha 410082, Peoples R China.
关键词:
DNA;similarity;graphical representation;5-D representation;3-D GRAPHICAL REPRESENTATION;NUMERICAL CHARACTERIZATION;SIMILARITY/DISSIMILARITY;CURVES
摘要:
We propose a 5-D representation of DNA sequences based on the classifications of the four basic acid bases A,T,G, and C. The use of the 5-D representation is illustrated by constructing sequence invariants based on the entries in derived sequence matrices restricted to a selected width of a band along the main diagonal. As an application, we make a comparison for the first exon of beta-globin gene sequences belonging to eleven different species based on the 5-D representation.
语种:
英文
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