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Tsallis model-based separation of overlapped peak signals

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Science china(information Sciences) 2010年第4期53卷 823-832页

作者： LI YuanLu*, ZHANG YingChao & TANG HuiQiang college of information and Control, Nanjing university of information Science & technology, Nanjing 210044, china 1. college of information and Control Nanjing University of Information Science & Technology Nanjing 210044 China

A simple scheme for separating overlapped peak signals (OPS) is proposed, with the Tsallis distribution as the model for OPS processing and fractional-order differentiation as tool for the signal analysis, the relationships of the maxima and zero-crossing values of the Tsallis peak signal, separately, to the order of differentiation are established, leading to two types of parameter estimators, which are utilized, by adjusting the peak-shape parameter, to calculate the parameters of position, height and width of the Gaussian, Lorentzian and Tsallis distribution. The obtained characteristic parameters can be employed to fit the peak signals to be treated, thereby fulfilling the OPS decomposition.

关键词： fractional differentials filter overlapped peak signal Tsallis model separation of overlapped peak signals

Surface characteristics of rapidly solidified nickel-based superalloy pow-ders prepared by PREP

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Rare Metals 2003年第4期22卷 309-314页

作者： CHEN Huanming , HU Benfu , and LI Huiying1) School of Materials Science and engineering, university of Science and technology Beijing, Beijing 100083, china2) School of Physics and electrical information engineering, Ningxia university, Yinchuan 750021, china School of Materials Science and engineering University of Science and Technology Beijing Beijing 100083 Chins

The surface microstructure and the surface segregation of FGH 95 nickel-basedsuperalloy powders prepared through plasma rotating electrode processing (PREP) have beeninvestigated by using SEM and AES. The results indicate that the surface microstructure of powderschanges from dendrite into cellular stricture as the particle size of powders decrease, and thepredominant precipitates solidified on the particle surfaces were identified as MC' type carbidesenriched with Nb and Ti. It was also indicated that along with the depth of particle surfaces, thesegregation layer of S, C and O elements are thick, and that of Ti, Cr elements are thin for largesire powders while they are in reverse for median size particles.

关键词： FGH 95 nickel-based superalloy powders surface characteristics microstructure plasma rotating electrode processing

Large eddies induced by local impulse at wall of boundary layer with pressure gradients

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Progress in Natural Science:Materials International 2008年第7期18卷 873-878页

作者： Changgen Lu a,b,*, Weidong Caob, Yanmei Zhang b, Jintao Pengb a college of Atmospheric Science, Nanjing university of information Science & technology, Nanjing 210044, china b college of Environmental Science and engineering, Hohai university, Nanjing 210098, china college of Atmospheric Science Nanjing University of Information Science & Technology Nanjing 210044 China college of Environmental Science and engineering Hohai University Nanjing 210098 China

Large eddies induced by local impulse at the wall with pressure gradients in the boundary layer was studied by direct numerical sim- ulations. The results show that the amplitude evolution, the high and low speed stripes, the formation of streamwise vortices, the ejection and sweeping, inflexions and distortion at the mean velocity profiles, as well as other characteristics, are consistent with the experimental and other numerical results. It is also found that large eddies are easy to be excited with adverse pressure gradient in the boundary layer, and the growth of amplitudes, formation of streamwise vortices and the influencing area etc., are much larger than those with favorable pressure gradient in the boundary layer. In contrast, large eddies are hardly to be induced through local impulse disturbance at the wall with favorable pressure gradients in the boundary layer.

关键词： Boundary layer Pressure gradients Impulse Large eddies

Deterministic secure quantum communication without unitary operation based on high-dimensional entanglement swapping

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Science china(information Sciences) 2012年第2期55卷 360-367页

作者： LIU ZhiHao1,CHEN HanWu1,LIU WenJie2,XU Juan1 & LI ZhiQiang3 1School of Computer Science and engineering,Southeast university,Nanjing 211189,china 2School of Computer and Software,Nanjing university of information Science & technology,Nanjing 210044,china 3college of information engineering,Yangzhou university,Yangzhou 225009,china 1. School of Computer Science and engineering Southeast University Nanjing 211189 China2. School of Computer and Software Nanjing University of Information Science & Technology Nanjing 210044 China3. College of Information Engineering Yangzhou University Yangzhou 225009 China

By analysis of the basic properties of entanglement swapping of high-dimensional Bell states,a universal and general deterministic secure quantum communication(DSQC)protocol is proposed,in which unitary operation is not *** making use of the results of high-dimensional Bell measurement,the sender and the receiver can encode and decode the message respectively by performing the modular addition and *** mutually complementary bases are constructed;and according to the property of mutual complement,a method for checking security of the high-dimensional quantum channel is put *** common attack strategies are analyzed,and the corresponding error rates are *** the upper bound of the threshold of error rate is deduced.

关键词： deterministic secure quantum communication high-dimensional Bell state entanglement swap-ping high-dimensional Bell measurement

Design of sequence set with group-wise zero correlation window

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The Journal of china Universities of Posts and Telecommunications 2009年第2期16卷 39-41页

作者： WANG Yang-zhi XU Cheng-qian college of information Science and engineering,Yanshan university,Qinhuangdao 066004,china [a]college of information Science and engineering Yanshan university Qinhuangdao 066004 china

Zero correlation window （ZCW） or zero correlation zone （ZCZ） sequence can be used in quasi-synchronous code division multiple access （QS-CDMA） system to eliminate multiple access and multipath interferences. However, as the length of ZCW or ZCZ increases, fewer sequences are available. Recently, a new concept, sequence set with group-wise zero correlation window is introduced, which can increase the number of available sequences for a QS-CDMA system. In this article, a new method for generating sequence set with group-wise zero correlation window is presented. This method is based on a Hadamard matrix of size N×N and a pair of Hadamard matrices of size M×M. Compared with previous methods, the proposed sequence set has a group-wise zero correlation window for both periodic and aperiodic cross-correlation functions.

关键词： ZCW group-wise zero correlation window multiuser detection Hadamard matrix

同步电动机做步进运动状态时的MATLAB仿真

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铁道学报 2004年第6期26卷 62-66页

作者：胡彦奎陶彩霞兰州交通大学信息与电气工程学院甘肃兰州730070

根据电机统一理论与电机步进运动特点,利用电机的矩阵分析方法,建立了同步电机做步进运动时的数学模型。运用MATLAB语言中的Simulink仿真工具对动态过程进行仿真分析,仿真结果有助于系统最佳参数的选择。

关键词：同步电动机步进运动 MATLAB仿真

Photoresponsive organogel and organized nanostructures of cholesterol imide derivatives with azobenzene substituent groups

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Progress in Natural Science:Materials International 2012年第1期22卷 64-70页

作者： Tifeng Jiao a,b,c,Yujin Wang a,Fengqing Gao a,Jingxin Zhou a,Faming Gao a a Hebei Key Laboratory of Applied Chemistry,college of Environmental and Chemical engineering,Yanshan university,Qinhuangdao 066004,china b college of Chemistry & Materials engineering,Wenzhou university,Wenzhou 325027,china c State Key Laboratory of Solid Lubrication,lanzhou Institute of Chemical Physics,Chinese Academy of Sciences,lanzhou 730000,china [a] Hebei Key Laboratory of Applied Chemistry College of Environmental and Chemical Engineering Yanshan University Qinhuangdao 066004 China [b] college of Chemistry & Materials engineering Wenzhou University Wenzhou 325027 China [c] State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou 730000 China

Two new cholesterol imide derivatives with azobenzene substituent groups have been *** compounds possess headgroups of hydrogen or methyl units,*** gelation test revealed that a subtle change in the headgroup of azobenzene segment produced a dramatic change in the gelation behavior of both *** compound with headgroups of hydrogen units only gelated N,N-Dimethylformamide(DMF),while the other compound with headgroups of methyl units cannot gelate any solvent tested *** DMF gel and solution of the gelator,the reversible photoisomerization transitions by irradiation with ultraviolet(UV) and visible light are investigated by UV-vis absorption spectra,Fourier transform infrared spectrometer,scanning electron microscope,atomic force microscope,and X-ray diffraction *** UV irradiation of the gel,trans-cis photoisomerization of the azobenzene groups occurs,the change in molecular polarity leads to the breaking of van der Waals interactions,resulting in the gel-sol *** gel can be recovered by the reverse cis-trans photoisomerization after exposure to visible *** and spectral studies reveal that the gelator molecules selfassemble into one-dimensional fibers,which further crossed-linked to form regular *** results afford useful information for the development of new versatile low molecular mass gelators and soft matter.

关键词： Organogel Cholesterol Azobenzene Photoisomerization Soft material

Contourlet HMT model with directional feature

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Science china(information Sciences) 2012年第7期55卷 1563-1578页

作者： WANG XiangHai 1,2,3 ,CHEN MingYing 1 ,SONG ChuanMing 1,2 ,XU MengChun 1 & FANG LingLing 3 1 college of Computer and information technology,Liaoning Normal university,Dalian 116029,china 2 State Key Laboratory for Novel Software technology,Nanjing university,Nanjing 210093,china 3 Provincial Key Laboratory for Computer information Processing technology,Soochow university,Suzhou 215006,china 1. college of Computer and information technology Liaoning Normal University Dalian 116029 China2. State Key Laboratory for Novel Software Technology Nanjing University Nanjing 210093 China3. Provincial Key Laboratory for Computer Information Processing Technology Soochow University Suzhou 215006 China

According to Shanno's information theory,the directional feature of texture is defined as the value of directional variable when an image signal attains a singularity of random *** terms of this definition,we calculate the texture's directional features using Tamura's method and study the directional probability distribution of Contourlet *** we find that the directional features tend to be conveyed across parent and child *** on this conclusion,we establish a novel probability distribution model of hidden direction variables under the condition of hidden state variable's distribution,named Contourlet HMT model with directional *** structure and training method of the model are presented as ***,an unsupervised context-based image segmentation algorithm is proposed on the basis of the proposed *** effectiveness is verified via extensive experiments carried out on several synthesized images and remote sensing images.

关键词： directional feature Contourlet HMT Contourlet HMT with directional feature unsupervised texture segmentation

Online multiple instance regression

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Chinese Physics B 2013年第9期22卷 656-661页

作者：王志岗赵增顺张长水 Department of Automation Tsinghua UniversityState Key Laboratory of Intelligent Technologie and SystemsTsinghua National Laboratory for Information Science and Technology college of information and electrical engineering Shandong University of Science and Technology School of Control Science and engineering Shandong University

The multiple instance regression problem has become a hot research topic recently. There are several approaches to the multiple instance regression problem, such as Salience, Citation KNN, and MI-ClusterRegress. All of these solutions work in batch mode during the training step. However, in practice, examples usually arrive in sequence. Therefore, the training step cannot be accomplished once. In this paper, an online multiple instance regression method ＂OnlineMIR＂ is proposed. OnlineMIR can not only predict the label of a new bag, but also update the current regression model with the latest arrived bag. The experimental results show that OnlineMIR achieves good performances on both synthetic and real data sets.

关键词： mutiple instance regression online learning