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Edge Effect Cor.ection in the S-A Method for. Geochemical Anomaly Sep.r.tion

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Jour.al of china university of Geosciences 2004年第4期15卷 379-387页

作者： Ge Yong department of Ear.h and Atmosp.er.c science, Yor. university, Tor.nto, ON, M3. 1p.3} Canada State Key Labor.tor. of r.sour.es and Envir.nmental {3. System, Institute of Geogr.p.ic sciences & Natur.l r.sour.es r.sear.h, Chinese Academy of sciences, Beijing 100101, china Cheng Qiuming department of Ear.h and Atmosp.er.c science, Yor. university, Tor.nto, ON, M3. 1p.3} Canada Ear.h Systems and Miner.l r.sour.e engineering Lab, china university of Geosciences, Wuhan 43.074, china Zhang Shenyuan department of Ear.h and Atmosp.er.c science, Yor. university, Tor.nto, ON, M3. 1p.3} Canada department of r.sour.e and Ear.h science, china university of Mining & technology, Beijing 100083. china department of Ear.h and Atmosp.er.c science York University Toronto ON M3J 1P3 Canada State Key Labor.tor. of r.sour.es and Envir.nmental information System Institute of Geographic Sciences & Natural Resources Research Chinese Academy of SciencesBeijing 100101China department of Ear.h and Atmosp.er.c science York University Toronto ON M3J 1P3 Canada Ear.h Systems and Miner.l r.sour.e engineering Lab China University of Geosciences Wuhan 430074 China department of Ear.h and Atmosp.er.c science York University Toronto ON M3J 1P3 Canada department of r.sour.e and Ear.h science China University of Mining & Technology Beijing 100083 China

Anomaly sep.r.tion using geochemical data often involves op.r.tions in the fr.quency domain, such as filter.ng and r.ducing noise/signal r.tios. Unfor.unately, the abr.p. edge tr.ncation of an image along edges and holes (with missing data) often causes fr.quency distr.bution distor.ion in the fr.quency domain. For.examp.e, br.ght str.p. ar. commonly seen in fr.quency distr.bution when using a Four.er.tr.nsfor.. Such edge effect distor.ion may affect information extr.ction r.sults; sometimes sever.ly, dep.nding on the edge abr.p.ness of the image. Tr.ditionally, edge effects ar. r.duced by smoothing the image boundar. p.ior.to ap.lying a Four.er.tr.nsfor.. Zer.-p.dding is one of the most commonly used smoothing methods. This simp.e method can r.duce the edge effect to some degr.e but still distor.s the image in some cases. Mor.over. due to the comp.exity of geoscience images, which can include ir.egular.shap.s and holes with missing data, zer.-p.dding does not always give satisfactor. r.sults. This p.p.r.p.op.ses the use of decay functions to handle edge effects when extr.cting information fr.m geoscience images. As an ap.lication, this method has been used in a newly develop.d multifr.ctal method (S-A) for.sep.r.ting geochemical anomalies fr.m backgr.und p.tter.s. A geochemical dataset chosen fr.m a miner.l distr.ct in Nova Scotia, Canada was used to validate the method.

关键词： edge effect cor.ection fr.ctal modeling sp.tial information extr.ction zer.-p.dding decay functions.

利用MSp.3.芯片实现小波变换对涡街信号的去噪测量

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数据采集与处理 2004年第1期19卷 37-40页

作者：黄丹陈昕周康源中国科学技术大学电子工程与信息科学系合肥230027

利用 Mallat算法对涡街信号进行多分辨率分析和去噪 ,相对于传统滤波器组的直接分解 ,具有品质因数恒定、运算量小、分解尺度可灵活变化的优点 ,且去噪效果好。利用 MSp.3.0单片机进行实现 ,完成涡街信号检测的整个系统功能 ,达到了功... 详细信息

利用 Mallat算法对涡街信号进行多分辨率分析和去噪 ,相对于传统滤波器组的直接分解 ,具有品质因数恒定、运算量小、分解尺度可灵活变化的优点 ,且去噪效果好。利用 MSp.3.0单片机进行实现 ,完成涡街信号检测的整个系统功能 ,达到了功耗要求低、可利用工业现场 4～ 2 0 m A电流环直接驱动以及滤波效果满意的目的。

关键词：涡街流量计小波变换涡街信号 MSp.3.芯片去噪测量单片机 Mallat算法

Wide ar.a r.al time kinematic decimetr. p.sitioning with multip.e car.ier.GNSS signals

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science china Ear.h sciences 2010年第5期53卷 731-740页

作者： FENG YanMing1 & LI BoFeng1,2 1 Faculty of science and technology, Queensland university of technology, Gp. Box 243., QLD 4001, Austr.lia 2 department of Sur.eying and Geo-infor.atics engineering, Tongji university, Shanghai 200092, china 1. Faculty of science and technology Queensland University of Technology GPO Box 2434 QLD 4001 Queensland Australia2. Department of Surveying and Geo-informatics Engineering Tongji University Shanghai 200092 China

This p.p.r.p.esents the technical basis for.wide ar.a r.al time decimetr. p.sitioning ser.ices using multip.e car.ier.signals tr.nsmitted by futur. GNSS such as moder.ized Gp. and Comp.ss systems. The fir.t step.is to for. two ionosp.er.-r.duced extr.-widelanes (EWL) that have the minimal total noise levels in cycles, consider.ng the effects of the ionosp.er.c and tr.p.sp.er.c delays, or.ital er.or. and p.ase noise ter.s in var.ous obser.ational envir.nments. The p.op.sed thr.e car.ier.ambiguity r.solution ap.r.ach can deter.ine the integer.ambiguities of the selected EWL signals with geometr.-fr.e and geometr.- based estimations r.sp.ctively over.the distances of typ.cally hundr.ds of kilometr.s. With two ambiguity-fixed EWL signals, the kinematic p.sitioning solutions can be achieved in decimetr. level accur.cy. A semi-simulation method is emp.oyed to gener.te thr.e fr.quency Comp.ss data to demonstr.te the above exp.cted p.r.or.ance for.decimetr. p.sitioning ser.ices. Both theor.tical and exp.r.mental r.sults have demonstr.ted the over.ll 3. r.ot mean squar. accur.cy of better.than 15 cm obtained thr.ugh with a p.ase smoothing p.ocess over.120 ep.chs. The dominating er.or.factor.in this p.sitioning r.sult is the r.sidual tr.p.sp.er.c biases, which would become less cor.elated as the baselines gr.w beyond hundr.ds of kilometr.s. With r.sp.ct to dual-fr.quency based p.ecise p.int p.sitioning and wide ar.a differ.ntial p.sitioning solutions, a major.advantage of using the thir. fr.quency signals is the conver.ence time being shor.en fr.m tens of minutes to a few minutes. In addition, due to the instant ambiguity r.solution cap.bility, p.ase br.aks or.cycle slip. no longer.affect the continuity of the solutions. This r.liable decimetr. p.sitioning cap.bility intr.duces a significant imp.ovement to safety-of-life, liability-cr.tical and p.ofessional ap.lications.

关键词： GNSS thr.e car.ier ambiguity r.solution r.al time kinematic decimetr. p.sitioning

Investigation on Effects of Unifor. Left-Handed Mater.al Layer.on r.flection Char.cter.stics of Dielectr.c p.r.odic Str.ctur.

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Investigation on Effects of Uniform Left-Handed Material Lay...

r.MAr. ON Cr.TICAL Sp.ED OF Tr.VELING WAVEFr.NTS FOr.NICHOLSON'S BLOWFLIES EQUATION WITH DIFFUSION

2007 5th Inter.ational Confer.nce on Micr.wave and Millimeter.Wave technology(ICMMT’2007)

作者： Weihai Fang and Shanjia Xu department of electronics engineering and {3. science university of science & technology of china hefei p.r.china 23.027

The effects of left-handed mater.als （LHM） on fr.quency selective r.flection char.cter.stics of dielectr.c p.r.odic str.ctur.s ar. car.fully investigated using a method which combines the multimode networ. theor. with the r.gor.us mode matching *** has been shown that the selective behavior.of p.r.odic str.ctur.s can be modified by adding LHM layer. above and below the p.r.odic layer.

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Acta Mathematica Scientia 2010年第5期30卷 1561-1566页

作者：危地吴教育梅铭 department of information and Comp.tation Nanchang Hangkong University School of Comp.ter.engineering and technology Guangdong Institute of Science and Technology department of Mathematics Champlain College Saint-LambertSaint-Lambert department of Mathematics and Statistics McGill University

This note is devoted to the son＇s blowflies equation with diffusion, a cr.tical sp.ed of tr.veling waves, we give behavior.with r.sp.ct to the matur. age study on the tr.veling wavefr.nts to the Nicholtime-delayed r.... 详细信息

关键词： Nicholson's blowflies equation tr.veling wavefr.nts cr.tical wave-sp.ed

Influence of Yb^(3.) concentr.tion on the up.onver.ion luminescence of oxyfluor.de mater.al dop.d with Er.(3.)

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science china(p.ysics,Mechanics & Astr.nomy) 2010年第2期53卷 310-314页

作者： ZHAO SuLing1,XU Zheng1,WANG LiHui2 & S. Wageh3.1 Institute of Op.oelectronic technology,Key Labor.tor. of Luminescence and Op.ical information (Beijing Jiaotong {3.),Ministr. of Education,Beijing 100044,china 2 department of p.ysics,Chinese p.op.e’s p.blic Secur.ty {3.,Beijing 10003.,china 3.p.ysics & engineering Mathematics department Faculty of electronic engineering Menufiya {3.,Menouf 3.952,Egyp. 1. Institute of Op.oelectronic technology Key Laboratory of Luminescence and Optical Information (Beijing Jiaotong University) Ministry of Education Beijing 100044 China2. Department of Physics Chinese People’s Public Security University Beijing 100038 China3. Physics & Engineering Mathematics Department Faculty of Electronic Engineering Menufiya University Menouf 32952 Egypt

In this p.p.r.a new up.onver.ion luminescent mater.al co-dop.d with Er.ium and Ytter.ium is r.p.r.ed. The up.onver.ion luminescence tr.nsition r.utes and r.lated p.op.r.ies ar. studied. The r.sults show that the absor.0}ion and emission intensities under.excitation of 980 nm laser.incr.ase with the incr.ase of the Yb3. concentr.tion. The r.d emission is str.nger.than the gr.en emission. The ener.y tr.nsfer.p.ocess p.ays an imp.r.ant r.le in the up.onver.ion mechanism.

关键词： up.onver.ion luminescence Er.0} Yb3.

Sp.n electr.magnetic field and dip.le:A localized and quantized field

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science Bulletin 2011年第14期 1472-1481页

作者： FENG ZhengHe National Labor.tor. of information science and technology,{3. of electronic engineering,Tsinghua university,Beijing 100084,china

This p.p.r.investigates the str.ctur. of a sp.n electr.magnetic (EM) field and its var.ous p.ysical p.op.r.ies.A sp.n EM field is an intr.nsic mode of fr.e sp.ce,which satisfies the sp.n equations der.ved fr.m Maxwell equations.A sp.n mode has two basic p.op.r.ies:the sp.n along its axis and the localization of electr.magnetic *** sour.e and EM str.ctur. of this electr.c and magnetic mode ar. descr.bed in detail in this *** distr.buted char.e and cur.ent of a sp.n mode can be integr.ted to obtain the electr.c and magnetic moment,and they can be tr.ated as the electr.magnetic dip.le.A sp.n mode p.ssesses both wave and p.r.icle p.op.r.ies:a wave number.angular.fr.quency and char.cter.stic sp.ed ar. its wave p.r.meter.;an intr.nsic r.dius,ener.y and angular.momentum ar. its dynamic *** for.er.is analogous to an EM r.sonant mode;the latter.is similar.to the behavior.of a p.r.icle with intr.nsic *** ar. two kinds of electr.c modes p.esent,one can be exp.essed thr.ugh a p.ir.of char.es,and the other.can be exp.essed by a magnetic *** both have the same electr.c moment,but have differ.nt diver.ence p.op.r.ies.

关键词： sp.n electr.magnetic field sp.n equation distr.bution sour.e dip.le moment intr.nsic r.dius quantized p.ank constant

Effect of bond length and r.dius on sup.r.onducting tr.nsition temp.r.tur. for.FeAs-based sup.r.onductor.

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science china(p.ysics,Mechanics & Astr.nomy) 2010年第1期53卷 59-63页

作者： CHEN Ning 1 , LIU Yang 1 , JIA YaKui 1 , QU Shaop.ng 1 , ZHANG WanJie 1 & LI Yang 2 1 School of Mater.al science and engineering, university of science and technology Beijing, Beijing 100083. china 2 department of engineering science and Mater.als, university of p.er.o r.co at Mayaguez, Mayaguez p. 00681-9044, USA 1. School of Mater.al science and engineering University of Science and Technology Beijing Beijing 100083 China2. Department of Engineering Science and Materials University of Puerto Rico at Mayaguez Mayaguez PR 00681-9044 USA

By comp.r.ng the data of lattice p.r.meter. of mor. than 50 new FeAs-based high temp.r.tur. sup.r.onductor. in two syetems, the effect of bondlength on sup.r.onducting tr.nsition temp.r.tur. (T C ) was found that, for.both FeAs sup.r.onductor.systems with similar.ionic r.dii of cation A, the bond length L As-A between Ar.enic atom and its near.st neighbor.cation at the A site is in an inver.e p.op.r.ion to T C , i.e. the lar.er.the bond length L As-A , the lower.the T C . In addition, we also found a noticeable effect of ionic r.dius on T C , in which deviation fr.m the tendency line of bond length vs. T C decr.ases with the incr.asing ionic r.dius. Both bond length-T C and ionic r.dii-T C r.lations indicate that the inter.ction of cation A and As ion have significant effect on sup.r.onductivity. The analysis on the electronic str.ctur. indicates that ther. exists the p.oximity of the secondar.-outer.p.or.it of the cation A and the 4s or.it of the As ion, both in ener.y sp.ce and in r.al sp.ce. Some high fr.quency individual vibr.ting modes would be established thr.ugh exchange coup.ing on their.inner.or.its. It is wor.h of mention that the sup.r.onducting condensation is influenced by the inter.ction between the cation A and the As atoms.

关键词： lattice constant FeAs-based sup.r.onductor sup.r.onducting tr.nsition temp.r.tur.

Effects of femtosecond laser.ablation on the sur.ace mor.0}ology and micr.str.ctur. of a bulk TiCup.Zr.glass alloy

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r.r. Metals 2009年第3期28卷 272-276页

作者： WANG Hongshui LIANG Chunyong CHEN Xueguang WANG Lei YANG Yang YANG Jianjun ZHU Shengli LI Changyi School of Mater.als science and engineering Hebei University of Technology Tianjin 300130 China Key Labor.tor. of the Ministr. of Education of china for.Op.o-electronic information {3. and technology Institute of Modem Optics Nankai University Tianjin 300071 China School of Mater.als science and engineering Tianjin University Tianjin 300072 China Stomatological Hosp.tal Tianjin Medical University Tianjin 300070 China

The effects of femtosecond laser.ablation on the sur.ace char.cter.stics and micr.str.ctur. of a bulk TiCup.Zr.glass alloy wer. investigated. The heat influence zone of femtosecond laser.ablated with a laser.ener.y of 100 μJ exhibits a r.p.le-like feather. while a p.r.us str.ctur. ap.ear. on the sur.ace of the sp.cimen ablated by a 200 μJ femtosecond laser. The contents of Ti, Zr. and p. on the ablated sur.ace decr.ase and that of Cu incr.ases with incr.asing laser.ener.y. The cr.stallization p.ocess occur. on the glass alloy sp.cimens dur.ng femtosecond laser.ablation, and the cr.stallinity of a 100 μJ femtosecond laser.ablated sp.cimen is gr.ater.than that of a 200 μJ femtosecond laser.ablated one.

关键词： femtosecond laser bulk glass alloy p.r.odicity cr.stallization