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New Experimental Scheme of Quantum Teleportation and Dense Coding

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量子光学学报 2000年第3期 131-132页

作者： ZHANGJing , PENGKun -chi (InstituteofOpto -Electronics,ShanxiUniversity,Taiyuan 0 30 0 0 6P .R .China)

ItisacommonpursuitinthescientificandtecNewExperimentalSchemeofQuantumTeleportationandDenseCoding ZHANGJing , PENGKun -chi (InstituteofOpto -Electronics,ShanxiUniversity,Taiyuan 0 30 0 0 6P .R .China) Abstract:Itisacommonpursuitinthescientificandtechnicalfieldtofindouttheschememoreeasilytorealizethe quantumteleportationanddensecoding .Weconsiderateleportationschemebyusingasimple“Bell -state” measurementatAliceinsteadoftwobalancedhomodynedetectorsusually .OneoftheEPRbeamsisphase -shiftedπ/ 2 andtheniscombinedwiththeinputbeamofsameintensityon 50 %beamsplitter .Theamplitudeandphasequadratureareobtainedfromthedirectdetectionimplementedwithtwophoto -detectorsandtwoRFsplitters ,thereforethelocal oscillatorisnotneeded .Arealizableexperimentalsystemtoachievethecontinuous -variableteleportationbymeansof thebrightEPRbeamsisdescribed .ThenthedensecodingforcontinuousvariablebasedonusingbrightEPRbeamsand thedirectdetectionof“Bell -state”isdiscussed .Thetransmittedphaseandamplitudesignalsaremodulatedonthe phaseandamplitudequadratureofoneoftheEPRbeamsrespectively .Bobcombinesitwiththestandardquantumlimited (SQL)bythedirectdetectionof“Bell -state” .Thisschemeisactuallyequaltodensecodingfordiscretevariable .The densecodingcapacityapproachestwicethatofcoherent-stateandsqueezed -statecommunication .

关键词： Quantum Teleportation Dense Coding

ESTABLISHMENT OF THE OCEAN DYNAMIC SYSTEM WITH FOUR SUB-SYSTEMS AND THE DERIVATION OF THEIR GOVERNING EQUATION SETS

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Journal of Hydrodynamics 2012年第2期24卷 153-168页

作者： YUAN Ye-li QIA0 Fang-li YIN Xun-qiang HAN Lei LU Ming The First Institute of Oceanography State Oceanic Administration of ChinaQingdao 266061China

Based on their differences in physical characteristics and time-space scales,the ocean motions have been divided into four types in the present paper：turbulence,wave-like motion,eddy-like motion and *** the three-fold Reynolds averages to the governing equations with Boussinesq approximation,with the averages defined on the former three sub-systems,we derive the governing equation sets of the four sub-systems and refer to their sum as ＂the ocean dynamic system＂.In these equation sets,the interactions among different motions appear in two forms：the first one includes advection transport and shear instability generation of larger scale motions,and the second one is the mixing induced by smaller scale motions in the form of transport flux *** governing equation sets are the basis of analytical/numerical descriptions of various ocean processes.

关键词： ocean dynamic system four sub-systems advection transport shear instability transport flux residue

Fluid flow and heat transfer characteristics of spiral coiled tube: Effects of Reynolds number and curvature ratio

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Journal of Central South University 2012年第2期19卷 471-476页

作者： YOO Geun-jong CHOI Hoon-ki DONG wa-ryong School of Mechatronics Changwon National University

Numerical analysis was performed to investigate flow and heat transfer characteristics in spiral coiled tube heat exchanger. Radius of curvature of the spiral coiled tube was gradually increased as total rotating angle reached 12n. As the varying radius of curvature became a dominant flow parameter, three-dimensional flow analysis was performed to this flow together with different Reynolds numbers while constant wall heat flux condition was set in thermal field. From the analysis, centrifugal force due to curvature effect is found to have significant role in behavior of pressure drop and heat transfer. The centrifugal force enhances pressure drop and heat transfer to have generally higher values in the spiral coiled tube than those in the straight tube. Even then, friction factor and Nusselt number are found to follow the proportionality with square root of the Dean number. Individual effect of flow parameters of Reynolds number and curvature ratio was investigated and effect of Reynolds number is found to be stronger than that of curvature effect.

关键词： spiral coiled tube heat exchanger Reynolds number curvature ratio secondary flow friction factor Nusselt number

Effect of stand density and humus removal on regeneration of Pinus densiflora seedlings in a mixed conifer and broad-leaved forest

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Forestry Studies in China 2012年第2期14卷 85-91页

作者： WUChu-ping MakotoAND0 ZHANGJun SHENAi．hua YUANWei-gao ZHUJin—ru JIANGB0 ZhejiangForestryAcademy Hangzhou310023PR．China FieldScienceEducationandResearchCenter KyotoUniversityKitashirakawa—oiwakeKyoto6068502Japan

We studied the impact of stand density and forest floor humus removal on regeneration ofPinus densiflora in a mixed co- nifer and broad-leaved forest on the Daimonji-Yama Mountain, Kyoto, Japan. Three levels of stand density were set, i.e., a clear-cut site, a heavily thinned site and a lightly thinned site. In each density treatment, comparisons were carried out between humus removal （A0-free） and humus intact （A0-intact） subplots. We counted the emergence of sown pine seeds and measured survival and growth of pine seedlings over the next four years. In addition, light conditions and the recovery of understory were monitored. Results show that thinning intensity and humus removal promoted the establishment and growth of seedlings. One exception, however, was that seedling growth was minimal in the heavily thinned A0-intact subplots. This was due to a strong response of understory vegetation growth on the treatment combination, which hindered the pine seedling growth. Furthermore, we found that the canopy openness measured at 1.3-m height remained at least 35% for the heavily thinned site in 2008. The results suggest that the removal of the A0 layer after heavy thinning is the most effective and labor-saving operation for P. densifiora regeneration.

关键词： Pinus densiflora regeneration understory vegetation thinning forest operation

Thinning effects on walnut stem and crown diameter growth and fruiting in the walnut-fruit forests of Kyrgyzstan

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Journal of Mountain Science 2016年第9期13卷 1558-1566页

作者： Jean-Pierre SORG Zora Lea URECH Davlet MAMADZHAN0V Maik REHNUS Groupe deforesterie pour le developpement Department of Environmental SciencesETH Zurich8092 ZurichSwitzerland HEL VETAS Swiss Intercooperation 3001 BerneSwitzerland Laboratory of Forest Resources Forest Research Institute720015 BishkekKyrgyzstan Swiss Federal Research Institute WSL Ziircherstrasse 1118903 BirmensdorfSwitzerland

The walnut-fruit forests （Juglans regia L.） in southern Kyrgyzstan are considered to be biodiversity hotspots and of considerable economic and ecological importance to local populations. The fruiting ability and stability of these forests are, however, decreasing because of infrequent silvicultural interventions and non-existent natural regeneration. Continuous inventories and walnut harvest measurements were carded out on 18 trial and control plots over the course of i3 year. Results showed that i） thinning had a positive influence on diameter at breast height （dbh） increase, ii） dbh growth and crown area increases are strongly and positively correlated, iii） large crowns enhanced the production of fruits, and iv） temperature conditions had a major influence on the production of fruits. The above-mentioned points are particularly relevant for young plantations but are also valid for relatively old plantations （〉 50 years）. We conclude that regular thinning substantially improves diameter growth, fruit production and ability of trees to withstand wind and snow damage in both young stands and in older walnut-fruit forests.

关键词： Juglans regia Silviculture Orchardmanagement Fruit harvest Nut production

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Editorial

Science China(Physics,Mechanics & Astronomy) 2009年第12期52卷 1813-1814页

作者： Ping JinSong Qian ZhiHan Fung Lai-wa Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai200030China

Since the 1990s, a new round of lunar exploration missions have aroused profound interest of such big aerospace nations as U.S., Japan, Europe, China and India in broad-based active participation. In

关键词： VLBI Editorial CE

Added value of ratio of cross diameters of the appendix in ultrasound diagnosis of acute appendicitis

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World Journal of Gastrointestinal Surgery 2024年第1期16卷 21-28页

作者： Feng-wa Gu Si-Ze Wu Department of Ultrasound The First Affiliated Hospital of Hainan Medical UniversityHaikou 570102Hainan ProvinceChina

BACKGROUND The maximum outer diameter(MOD)of the appendix is an essential parameter for diagnosing acute appendicitis,but there is space for improvement in ultrasound(US)diagnostic *** To investigate whether combining the ratio of the cross diameters(RATIO)of the appendix with MOD of the appendix can enhance the diagnostic performance of acute *** A retrospective study was conducted,and medical records of 233 patients with acute appendicitis and 112 patients with a normal appendix were *** MOD and RATIO of the appendix were calculated and tested for their diagnostic performance of acute appendicitis,both individually and in *** The RATIO for a normal appendix was 1.32±0.16,while for acute appendicitis it was 1.09±*** cut-off value for RATIO was determined to be≤*** area under the receiver operating characteristic curve(AUC)for diagnosing acute appendicitis using RATIO≤1.18 and MOD>6 mm was 0.870 and 0.652,*** was a significant difference in AUC between RATIO≤1.18 and MOD>6 mm(P6 mm with MOD>6 mm alone,the combination showed increased specificity,positive predictive value(PPV),and ***,the sensitivity and negative predictive value *** Combining RATIO of the appendix≤1.18 and MOD>6 mm can significantly improve the specificity,PPV,and AUC in the US diagnosis of acute appendicitis.

关键词： Acute appendicitis Diameter Ratio Diagnosis Ultrasound

The wavelet Property of the Geomagnetic Anomaly Signal

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Communications in Nonlinear Science and Numerical Simulation 1997年第4期2卷 244-248页

作者： Jiangfa L IN &Gang waNG&Saizhen ZHANG&Yaosong CHEN (Dept. of Mech.,Peking Univ.,Bei Jing 1 0 0 871 ,P.R.China) Department of Mechanics and Engineering Science Peking University Beijing 100871 China

In this study,wavelet analysis is utilized to analyze the geomagnetic signals for oil- gas exploration,in order to show the relation between the wavelet property of the geomagnetic signals and the underground treasure. At first,the global geomagnetic anomaly signal in the oil exploration is ***,with the wavelet theory the geomagnetic signals of an oil- gas field is *** preliminary wavelet analysis shows thatthe underground oil- gas location can be determined with the help of its regional high frequency signal distributions.

关键词： wavelet analysis geomagnetic anomaly high frequency

北祁连山高压变质带的变形和变质特征及其对俯冲带折返的意义

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岩石学报 2009年第9期25卷 2235-2246页

作者：曹毅宋述光 CA0 Peking Univ MOE Key Lab Orogen Belts & Crustal Evolut Dept Geol Beijing 100871 Peoples R China

北祁连造山带是早古生代大洋板块"冷"俯冲的典型地区,形成了一系列高压低温变质的岩石组合。基性榴辉岩是俯冲洋壳变质的产物,根据其结构构造特征可以划分为(1)粒状榴辉岩,峰期变质矿物组合为Grt+Omp+Phn+Rut±Lws,硬柱石呈包裹体和假... 详细信息

北祁连造山带是早古生代大洋板块"冷"俯冲的典型地区,形成了一系列高压低温变质的岩石组合。基性榴辉岩是俯冲洋壳变质的产物,根据其结构构造特征可以划分为(1)粒状榴辉岩,峰期变质矿物组合为Grt+Omp+Phn+Rut±Lws,硬柱石呈包裹体和假象分布于石榴石内,变质温压条件T=465～508℃,p=2.30～2.60GPa。(2)片状榴辉岩,岩石具片状构造,其共生矿物组合Omp+Czo/Ep+Phn+Gln构成透入性面理S_1和线理L_1,以及宏观和显微同斜褶皱F_1。其峰期变质温压条件为T=466～510℃,P=1.9～2.2GPa。(3)蓝片岩相退化变质榴辉岩,蓝片岩相变质矿物Gln+Ep+Phn±Ab强烈交代榴辉岩相矿物,并发生强烈D_2期变形作用,岩石形成明显的透入性面理S_2和线理L_2,以及同斜剪切褶皱F_2。蓝闪石和多硅白云母线理的统计揭示D_2期变形以斜向走滑剪切为主,与D_1期变形的榴辉岩的运动学特征大体相似。D_2同变质的温压条件为T=422～487℃,P=1.15～1.37GPa。高压变质带晚期的绿片岩相叠加和D_3期变形,形成透入性面理S_3和线理L_3,其运动特征为近于垂直构造线的逆冲剪切。结合榴辉岩变形特征,变质温压条件和同位素年代学资料,我们认为退变质的强弱与变形程度有密切关系。峰期变质后的榴辉岩经过早期绿帘石榴辉岩相到蓝片岩相斜向走滑剪切,和晚期绿片岩相逆冲,在泥盆纪早期快速折返的出露地表。

关键词：北祁连山高压变质带变形变质特征俯冲带折返 implications 榴辉岩相峰期变质温压条件 mineral assemblage 蓝片岩相 North Qilian Mountains isotopic geochronology 走滑剪切线理绿片岩相矿物组合变质矿物 movement Early Paleozoic