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Lossless Watermarking Using Improved DE Method of Triplets

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Lossless Watermarking Using Improved DE Method of Triplets

2007北京地区高校研究生学术交流会通信与信息技术会议

作者： Lu Wenfeng~1 Jing Fang~2 Jian Yu~3 1 college of Management engineering,Shandong Jianzhu university Jinan 250101,china 2 college of physics and Electronics,Shandong normal university,Jinan 250014,china 3 Jinan Electronic Mechanical engineering School,Jinan 250101,china

The paper proposes an improved high-capacity data-hiding method to make some space to embed a *** proposed method uses spatial triplets of pixels to calculate the average value and the pair-wise difference values between the adjacent two elements to hide pairs of bits.A spatial triplet of pixels is any three adjacent pixel values (column or row-wise) extracted from the pixels of the *** the triplets of pixels into one of three *** record the location information of the Class One and Class Two to decrease the additional capacity caused by the location information and consequently improve the hiding *** experimental results show the hiding capacity is very high and the resulting distortion is very low.

关键词： Watermarking DE Triplets

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基于超混沌的活动图像的加密新方法

计算机工程与应用 2004年第35期40卷 53-54,144页

作者：肖要强王玲湖南师范大学物理与信息学院长沙410081

基于超混沌信号的非周期性和不收敛性,提出了利用超混沌信号对活动图像进行加密的一种新方法,详细地论述了加密矩阵的实现。用产生的加密矩阵随机地改变每一帧图像的每一个像素,并利用图像置乱变换技术来实现对活动图像加密的目的。实... 详细信息

基于超混沌信号的非周期性和不收敛性,提出了利用超混沌信号对活动图像进行加密的一种新方法,详细地论述了加密矩阵的实现。用产生的加密矩阵随机地改变每一帧图像的每一个像素,并利用图像置乱变换技术来实现对活动图像加密的目的。实验结果表明此方法是可行的。

关键词：活动图像加密加密矩阵置乱变换超混沌序列图像处理

Generation of high-energy dual-wavelength domain wall pulse with low repetition rate in an HNLF-based fiber ring laser

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Chinese physics B 2014年第6期23卷 217-220页

作者：罗智超林振彬李金玉朱鹏飞宁秋奕邢晓波罗爱平徐文成 Laboratory of Nanophotonic Functional Materials and Devices School of Information and Optoelectronic Science and Engineering South China Normal University Department of Environmental engineering Guangdong Industry Technical College MOE Key Laboratory of Laser Life Science and Institute of Laser Life Science College of BiophotonicsSouth China Normal University

The generation of high-energy dual-wavelength domain wall pulse with a low repetition rate is demonstrated in a highly nonlinear fiber （HNLF）-based fiber ring laser. By introducing the intracavity birefringence-induced spectral filtering effect, the dual-wavelength lasing operation can be achieved. In order to enhance the cross coupling effect between the two lasing beams for domain wall pulse formation, a 215-m HNLF is incorporated into the laser cavity. Experimentally, it is found that the dual-wavelength domain wall pulse with a repetition rate of 77.67 kHz could be efficiently obtained through simply rotating the polarization controller （PC）. At a maximum pump power of 322 mW, the 655-nJ single pulse energy in cavity is obtained. The proposed configuration provides a simpler and more efficient way to generate high energy pulse with a low repetition rate.

关键词： fiber lasers high-energy pulse domain wall low repetition rate

On the Zero-State Observability/Detectability of Switched and Hybrid Hamiltonian Systems with Infinite Number of Switching Subsystems

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On the Zero-State Observability/Detectability of Switched an...

第二十七届中国控制会议

作者： Zhu Liying1,Wang Yuzhen2 1.college of Mathematics,physics and information engineering,Zhejiang normal university,Jinhua 321004,P.R.china 2.School of Control Science and engineering,Shandong university,Jinan 250061,P.R.china

This paper investigates the zero-state observability and detectability of switched and hybrid dissipative Hamiltonian systems with infinite number of switching subsystems,and proposes a number of new results for the ***,study of two examples shows the complexity of the relationship between the zero-state detectability/observability of a switched and hybrid Hamiltonian system and that of its ***,by fully exploiting the Hamiltonian structural properties,the（uniform） zero-state observability and detectability of switched and hybrid Hamiltonian systems with infinite number of switching subsystems are investigated,and several criterions are obtained.

关键词： Hybrid hamiltonian system Zero-state detectability/observability Criterion Sufficient condition

A Fast Algorithm for Ontology Similarity Measure and Ontology Mapping

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A Fast Algorithm for Ontology Similarity Measure and Ontolog...

2011 4th IEEE International Conference on Computer Science and information Technology(ICCSIT 2011)

作者： Xiao Huang 1 2 1 college of Mathematics physics and information engineering Zhejiang normal university Zhejiang Jinhua 321004 P.R. china 2 college of Education Zhejiang normal university Zhejiang Jinhua 321004 P.R. china Wei Gao 3 4 3 Department of information Yunnan normal university Kunming 650092 P.R. china 4 Department of Mathematics Soochow university Suzhou 215006 P.R. china Tianwei Xu 3 3 Department of information Yunnan normal university Kunming 650092 P.R. china Zhiyang Jia 5 5 Tourism and Literature college Yunnan university Lijiang 674100 P.R.china

Ontology similarity calculation and ontology mapping are important research topics in information retrieval. By analyzing the fast algorithm for learning large scale preference relations, we propose the fast algorithm for ontology similarity measure and ontology mapping. Via the ranking learning algorithm, the ontology graph is mapped into a line consists of real numbers. The similarity between two concepts then can be measured by comparing the difference between their corresponding real numbers. Experimental results show that the proposed algorithm has high accuracy and efficiency.

关键词： ontology similarity computation ranking error function conjugate gradient H -exact approximation

Performance Analysis of Alamouti Scheme With Imperfect Multiple Transmit Antennas Selection in Rayleigh Fading Channel

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Performance Analysis of Alamouti Scheme With Imperfect Multi...

2006 7th International Symposium on Antennas, Propagation and EM Theory

作者： Zhuang Mingjie Lin Bihong (information college, Huaqiao university, Quanzhou, Fujian, 362021, P. R china) (information engineering college, Jimei university, Xiamen 361021, P. R. china) (Department of physics, Quanzhou normal university, Quanzhou 362000, R R. china)

In a multiple-input-single-output (MISO) communications system, we take the presence of the erroneous channel state information (CSI) into consideration. Multiple transmit antennas selection (TAS) over MSO systems with Alamouti space-time scheme is investigated, and a solution over order statistic characteristic of the selective channel with CSI feedback error is proposed. We assume that channel is an independent and flat Rayleigh fading channel and the system employs Binary Phase-Shift Keying (BPSK) modulation. The accurate analytical expressions of bit-error rate (BER) of Alamouti scheme with TAS have been derived. The analysis results show that when the error is existed in CSI we ought to try to choose the subset consisting of largest ordinal number as transmit in a practical system.

关键词： Alamouti space-time scheme, transmit antennas selection, CSI, BER, ordinal number, Rayleigh fading channel

Adaptive Filtering for Medical Image Based on 3-order Tensor Field

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Adaptive Filtering for Medical Image Based on 3-order Tensor...

第24届中国控制与决策会议

作者： Ping Zhang 1,2 , liqun gao 1 , Bin Fu 1 , Zhaohua Cui 1 , Xiaoyou Shan 2 1. college of information Science and engineering, Northeastern university, Shenyang, 110819,china2. physics Department, Anshan normal university, Anshan 114005, china

Structure tensors are a common tool for orientation estimation in image processing and computer vision. But the problem is that there is more than one significant orientation in corners, junctions, and multichannel images in second order model , In this paper, We provide a theoretical analysis for high order structure tensor which contains more configuration information in corners, junctions, and multichannel images better than second-order model. This paper deals with the problem of de-noising using 3D statistics. We present a novel non-iterative filter algorithm based on 3D tensor field . The algorithm consist of the following steps .Firstly,we sample every simple neighbourhood of the 3D data set and produced 3D tensor field according to a certain mapping relation. Secondly, According the characteristic of tensor filed , we can externalize the local orientation information which can control the size, shape and orientation of the filter. The highpass filter along with the main orientation of tensor to protect structure information from damage and low-pass filter along with the weak orientation denoising . we have tested this algorithm by medical image. The PSNR increased 32% averagely and the structure information was reserved well. Nevertheless, Better results the three order tensor got at the cost of low operating speed. Further work is to develop the operating speed in three order tensor.

关键词： 3D tensor orientation image de-noising filter

Ultra-wideband reflective polarization converter based on anisotropic metasurface

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Chinese physics B 2016年第8期25卷 402-406页

作者：吴家梁林宝勤达新宇 information and Navigation college Air Force Engineering University

In this paper, we propose an ultra-wideband reflective linear cross-polarization converter based on anisotropic metasurface. Its unit cell is composed of a square-shaped resonator with intersectant diagonal and metallic ground sheet separated by dielectric substrate. Simulated results show that the converter can generate resonances at four frequencies under normal incident electromagnetic（EM） wave, leading to the bandwidth expansion of cross-polarization reflection. For verification,the designed polarization converter is fabricated and measured. The measured and simulated results agree well with each other, showing that the fabricated converter can convert x- or y-polarized incident wave into its cross polarized wave in a frequency range from 7.57 GHz to 20.46 GHz with a relative bandwidth of 91.2%, and the polarization conversion efficiency is greater than 90%. The proposed polarization converter has a simple geometry but an ultra wideband compared with the published designs, and hence possesses potential applications in novel polarization-control devices.

关键词： polarization converter anisotropic metasurface ultra-wideband

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基于信息熵的IP网端到端行为分析与建模

计算机工程与应用 2004年第18期40卷 15-18,28页

作者：张连明陈志刚湖南师范大学物理与信息科学学院中南大学信息科学与工程学院长沙410083 中南大学信息科学与工程学院

具有开放、分布式、不协作、异构、无中心控制等特点的Internet复杂巨系统的管理、容量规划、新一代网络体系结构设计与分析和性能预测都离不开对网络行为的充分理解。而端到端行为作为网络行为的一个重要组成部分,具有一定的研究价值... 详细信息

具有开放、分布式、不协作、异构、无中心控制等特点的Internet复杂巨系统的管理、容量规划、新一代网络体系结构设计与分析和性能预测都离不开对网络行为的充分理解。而端到端行为作为网络行为的一个重要组成部分,具有一定的研究价值。该文利用信息熵原理建立用于分析端到端整体宏观行为的信息熵模型,该模型能很好地反映端到端整体宏观行为与链路上各节点的状态概率之间关系,根据该模型可以分析端到端链路上各节点之间的相互作用关系以及它们是如何引起端到端整体宏观行为的。最后,给出了该模型的有效性和稳定性定量分析的判别式。

关键词：网络宏观行为端到端行为信息熵状态概率