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Wavelet analysis of sunspot relative numbers

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Chinese Science Bulletin 2002年第7期47卷 609-612页

作者： HAN Yanben & HAN YonggangNational Astronomical Observatories, Chinese Academy of Sciences, beijing 100012. china Department of Applied Mathematics,{2., beijing 10002., china 1. National Astronomical Observatories Chinese Academy of Sciences 100012 Beijing China 2. Department of Applied Mathematics Beijing Polytechnic University 100022 Beijing China

The time series of the monthly smoothed sun-spot numbers in 1749-2.00 is analyzed with the wavelet. The result shows that besides the known time-variation of the period about 11 years, other main periods of the sunspot numbers, such as the periods of about 100 years and so on, vary with time. We suggest that the time-variation of the main periods is the manifestation of the complex variation of sunspot numbers. It is significant to make a thorough study of the character and mechanism of the time-variation of the periods for proving prediction of sunspot numbers, especially for understanding the variation process of sunspot numbers.

关键词： sunspot numbers prediction wavelet time-variation.

Changes in EEG measurements in intractable epilepsy patients with neurofeedback training

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Progress in Natural Science:Materials International 2009年第11期19卷 1509-1514页

作者： Longlian Zhao~a,Wenqing Wu~b,Zuoqing Liang~a,Guangshu Hu~(a,*) a Department of biomedical engineering,Tsinghua {2.,beijing 100084,china b Department of Neural Internal Medicine,beijing Friendship Hospital,beijing 100050,china [a]Department of biomedical engineering Tsinghua University Beijing 100084 China [b]Department of Neural Internal Medicine Beijing Friendship Hospital Beijing 100050 China

To assess the effects of neurofeedback on brain electrophysiology and to determine how biofeedback works,power spectral density (PSD) and approximate entropy(ApEn) analyses are applied to the EEGs of six patients with intractable epilepsy who received neurofeedback *** sessions of treatment,the EEG sensorimotor rhythm to theta PSD ratio calculated from the C4 electrode site becomes larger than that before the treatment,which is consistent with the biofeedback *** ApEn over 16-channel EEG recordings all increase to different *** increases occur in channels located near the training position(C4).All these results suggest that these EEG measurements are new criteria that can be used to evaluate the effect of neurofeedback.

关键词： Biofeedback Electroencephalogram Epilepsy Power spectral density Approximate entropy

Surface Carbonization of Mo La_2._3 Cathode

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中国有色金属学会会刊：英文版 1999年第3期9卷 442-445页

作者： Nie Zuoren(聂祚仁), Zuo Tieyong(左铁镛), Zhou Meiling(周美玲), Liu Danmin(刘丹敏), Wang Jinshu(王金淑) School of Materials Science and engineering, beijing polytechnic university,{2., P.R. china beijing Polytech Univ Sch Mat Sci & Engn Beijing 100022 Peoples R China

The carbonized structures of Mo La 2. 3 cathode specimens have been investigated by means of FESEM and XRD, respectively. The substructure of carbonized layer in the Mo La 2. 3 cathode has been found for the first time. The results showed that the carbonized layer with uniform Mo 2. was helpful to emission, while the demixing carbonized layer with a compact MoC outside layer was harmful to emission. The uniform Mo 2. layer consists of coarse particles with lots of grain boundary crevices as well as holes arranging perpendicular to the wire axle and up to surface, which was beneficial to the migration of activated rare earth in activation and operating.

关键词： microstructure cathodes Mo La 2. 3 carbonization emissionDocument code:A

Weak Morrey spaces and strong solutions to the Navier-Stokes equations

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Science china Mathematics 2007年第10期50卷 1401-1417页

作者： Chang-xing MIAO~(1+) Bao-quan YUAN~2.~1 Institute of Applied Physics and Computational Mathematics,P.O.Box 8009,beijing 100088,china ~2.College of Mathematics and Informatics,Henan {2. university,Jiaozuo 454000,china 1. Institute of Applied Physics and Computational Mathematics P.O. Box 8009 Beijing 100088 China 2. College of Mathematics and Informatics Henan Polytechnic University Jiaozuo 454000 China

We consider the Cauchy problem of Navier-Stokes equations in weak Morrey *** first define a class of weak Morrey type spaces M_(p,λ)~*(R^n)on the basis of Lorentz space L_(p,∞)=L_p~*(R^n) (in particular,M_(?)~*(R^n)=L_(p,∞),if p>1),and study some fundamental properties of them;Second, we prove that the heat operator U(t)= e^(tΔ)and Calderón-Zygmund singular integral operators are bounded linear operators on weak Morrey spaces,and establish the bilinear estimate in weak Morrey ***,by means of Kato's method and the contraction mapping principle,we prove that the Cauchy problem of Navier-Stokes equations in weak Morrey spaces M_(p,λ)~*(R^n)(1

关键词： Navier-Stokes equations, weak Morrey spaces, Lorentz spaces, Cauchy problem,time-global well-posedness, self-similar solutions

Formation of Superoxide Radical and Hydrogen Peroxide Enhanced by Trinitrotoluene in Rat Liver, Brain, Kidney, and Testicle in Vitro and Monkey Liver in Vivo

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biomedical and Environmental Sciences 1989年第1期2卷 72-77页

作者： KONG LINGYUAN, JIANG QUANGUAN,~2.AND QU QINGSHAN Department of Occupational Health, School of Public Health, beijing Medical university, beijing, china Department of Occupational Health School of Public Health Beijing Medical University China.

Trinitrotoluene (TNT) increased the formation of adrenochrome from adrenaline and the formation of formaldehyde from methanol in rat liver mitochondria and microsomes in vitro as well as in monkey liver mitrochondria and microsomes in vivo. The effects were more prominent at higher TNT concentrations. These findings indicate that TNT enhances the production of superoxide radicals (O_2.-) and hydrogen peroxide (H_2._2.. The production of O_2.- was more prominent in systems containing added TNT than in those containing added benzyl viologen. H_2._2.production by mitochondria was more pronounced in the liver than in other organs, but its production by microsomes was more pronounced in the brain than in other organs. The results suggest that TNT undergoes cycling reduction which produces oxidative stress. 1989 Academic Press, Inc.

关键词： Brain Formation of Superoxide Radical and Hydrogen Peroxide Enhanced by Trinitrotoluene in Rat Liver Kidney and Testicle in Vitro and Monkey Liver in Vivo

Preparation and microstructure of CuO-CoO-MnO/SiO2.nanocomposite aerogels and xerogels as catalyst carriers

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Progress in Natural Science:Materials International 2011年第4期21卷 330-335页

作者： Yue-qing ZHAO~1,Ying-hua LIANG~2.Xi-zhe ZHAO~3,Qian-yi JIA~4,Hong-sheng LI~4 1.College of Light Industry,Hebei United university,Tangshan 063000,china 2.College of Chemical {2.,Hebei United university,Tangshan 063009,china 3.College of Printing and Packaging {2.,beijing Institute of Graphic Communication,beijing 102.00,china 4.College of Materials Science and {2.,Hebei United university,Tangshan 063009,china [a] College of Light Industry Hebei United University Tangshan 063000 China [b] College of Chemical engineering Hebei United University Tangshan 063009 China [c] College of Printing and Packaging engineering Beijing Institute of Graphic Communication Beijing 102600 China [d] College of Materials Science and engineering Hebei United University Tangshan 063009 China

CuO-CoO-MnO/SiO2.anocomposite aerogels and xerogels were prepared using tetraethyl orthosilicate（TEOS） as Si source,and aqueous solution of Cu,Co and Mn acetates as the precursor via sol-gel process,CO2.upercritical drying（SCD） technique or ambient pressure drying *** microstructure of the CuO-CoO-MnO/SiO2.anocomposite aerogels and xerogels were characterized by field emission scanning electron microscopy（FE-SEM）,transmission electron microscopy（TEM） and X-ray diffraction（XRD）.The specific surface area,pore size and pore size distribution of the nanocomposite aerogels and xerogels were determined by the Brunauer-Emmett-Teller（BET） *** results showed that CuO-CoO-MnO/SiO2.anocomposite aerogels are porous,with a pore size distribution of 2.50 nm,an average pore size of 19.4 nm,a specific surface area of 384.9 m2.g and a particle size distribution of 10-150 nm,whereas the pore size distribution of CuO-CoO-MnO/SiO2.omposite xerogels is 1.7-12..6 nm,the average pore size is only 9.9 nm,the specific surface area is only 99.1 m2.g,and the particle size distribution is 100-500 *** structure of CuO-CoO-MnO/SiO2.anocomposite aerogels is favorable to increase the loading of catalysts.

关键词： composite aerogel composite xerogel catalyst carrier preparation microstructure

A Characterization for Windowed Fourier Orthonormal Basis with Compact Support

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Acta Mathematica Sinica,English Series 2001年第3期17卷 501-506页

作者： You Ming LIU Department of Applied Mathematics,beijing polytechnic {2..beijing 10002.,P.R.china E-mail:liuym@*** Department of Applied Mathematics Beijing Polytechnic University Beijing 100022 P. R. China

Let g（x） ∈L2.R） and （ω） be the Fourier transform of g（x）.Define gmn（x）=eimxg（x- 2.n）.In this paper we shall give a sufficient and necessary condition under which {gmn（x）} constitutes an orthonormal ba... 详细信息

Let g（x） ∈L2./sup>（R） and （ω） be the Fourier transform of g（x）.Define gmn（x）=eimxg（x- 2.n）.In this paper we shall give a sufficient and necessary condition under which {gmn（x）} constitutes an orthonormal basis of L2./sup>（R） for compactly supported g（x） or （ω）.

关键词： Windowed Fourier basis Congruence

Spatio-temporal model for soil characteristic of reclamation land

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中国有色金属学会会刊：英文版 2005年第S1期15卷 45-48页

作者： CHEN Qiu-ji~(1, 2., HU Zhen-qi~1, FU Mei-chen~3, XIE Hong-quan~4, HAO Hai-fu~5 (1. china university of Mining and Technology({2. Campus), {2. 100083, china 2. Henan polytechnic university, Jiaozuo 454000, china 3. china university of Geosciences, {2. 100083, china 4. Hebei polytechnic university, Tangshan 063009, china 5. china Railway Shiqiju Group Corporation, Taiyuan 030600, china) china Univ Min & Technol Beijing 100083 Peoples R China Henen Polytech Univ Jiaozuo 45400 Peoples R China china Univ Geosci Beijing 100083 Peoples R China Hebei Polytech Univ Tangshan 063009 Peoples R China china Railway Shiqiju Grp Corp Taiyuan 030600 Peoples R China

The development of spatio-temporal data model is introduced. According to the soil characteristic of reclamation land, we adopt the base state with amendments model of multi-layer raster to organize the spatio-temporal data, using the combined data structure on linear quadtree and linear octree to code. The advantage of this model is that it can easily obtain the information of certain layer and integratedly analyze the data with other methods. Then, the methods of obtain and analyses are introduced. The method can provide a tool for the research of the soil characteristic change and spatial distribution in reclamation land.

关键词： reclamation soil spatio-temporal data model linear quad-tree linear octree

A Review of Speech Coding

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通信学报 1998年第5期19卷 45-56页

作者： Bao ChangchunAssociate professor of Information engineering, beijing polytechnic university, Ph.D, CIE senior member (Department of Electronic engineering, beijing polytechnic university, beijing 10002.) Fan ChangxinProfessor with Xidian university, C

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关键词：语音编码线性估计综合分析波形编码