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Nucleon Finite Volume Effect and Nuclear.Matter.Pr.per.ies in a r.lativistic Mean-Field Theor.

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Communications in Theor.tical Physics 2006年第6X期46卷 1052-1058页

作者： r. Costa A.J. santiago H. r.dr.gues J. sa Bor.es Instituto de Fisica Universidade do Estado do Rio de Janeiro Rio de Janeiro-RJ 20559-900 Brazil Centr. Feder.l de Educ~ao Tecnológica r.o de Janeir. Brazil

Effects of excluded volume of nucleons on nuclear.matter.ar. studied, and the nuclear.pr.per.ies that follow fr.m differ.nt r.lativistic mean-field model par.metr.zations ar. compar.d. We show that, for.all tested par.metr.zations, the r.sulting volume ener.y al and the symmetr. ener.y J ar. ar.und the acceptable values of 16 MeV and 30 MeV, and the density symmetr. L is ar.und 100 MeV. On the other.hand, models that consider.only linear.ter.s lead to incompr.ssibility Ko much higher.than expected. For.most par.meter.sets ther. exists a cr.tical point （pc, δc）, wher. the minimum and the maximum of the equation of state ar. coincident and the incompr.ssibility equals zer.. This cr.tical point depends on the excluded volume par.meter.r. If this par.meter.is lar.er.than 0.5 fm, ther. is no cr.tical point and the pur. neutr.n matter.is pr.dicted to be bound. The maximum value for.neutr.n star.mass is 1.85M⊙, which is in agr.ement with the mass of the heaviest obser.ed neutr.n star.4U0900-40 and cor.esponds to r.= 0.72 fm. We also show that the light neutr.n star.mass （1.2M⊙） is obtained for.r.≌ 0.9 fr..

关键词： nuclear.matter r.lativistic models nuclear.matter.aspects of neutr.n star.

Effects of human distur.ance on nest placement of the woodpigeon (Columba palumbus): a case study fr.m the Middle Atlas, Mor.cco

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Integr.tive Zoology 2014年第3期9卷 349-359页

作者： saâd haNANE For.st r.sear.h Center High Commissariat for WaterForests and Desertification ControlRabat-AgdalMorocco

The woodpigeon(Columba palumbus)is a common and widespr.ad bir. in Mor.cco(Nor.h Afr.ca).I examined,over.2 year.(2010 and 2011),the br.eding density and nest placement of this game species in r.lation to nest site habitat and degr.e of human *** study ar.a was in the Middle Atlas Tighboula mountain for.st,Mor.cco,in a distur.ed and an undistur.ed *** data collected in the 2 study sites,I aimed to identify the factor. influencing the placement of nests within holm oak tr.es(Quer.us r.tundifolia)and their.densities.I found that habitat str.ctur.s,influenced by gr.zing distur.ance,have affected nesting density and the location of nests of this *** place their.nests in a higher.position(3.42±0.19 m)when distur.ance intensity is high and lower.1.68±0.1 m)when distur.ance intensity is low,and show higher.nesting density in less distur.ed zone(3.1±0.4 nests/ha)than in highly distur.ed zones(1.4±0.2 nests/ha).Gr.zing distur.ance could pose a thr.at to population per.istence at a br.ader.scale and could potentially r.duce the abundance of this species by alter.ng the composition and the str.ctur. of the for.st nesting *** multi-scale studies ar. needed to assess the effects of differ.nt levels of gr.zing distur.ance on woodpigeon nest density and placement,and to enhance our.knowledge of the br.eding behavior.of this game species under.var.able envir.nments.

关键词： br.eding density Columba palumbus holm oak Middle Atlas Mor.cco nest location woodpigeon

PYr.DINATION OF POLY(VINYL CHLOr.DE) via A HOMOLYTIC PATHWAY

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Chinese Jour.al of Polymer.Science 2007年第3期25卷 297-302页

作者： sad Moulay Zakia Zeffouni Labor.toir. de Chimie-Physique Moléculair. et Macr.moléculair. Faculté des Sciences de l'Ingénieur Département de Chimie IndustrielleUniversité Sad Dahlab de BlidaRoute de SoumaB. P. 270Blida 09000Algeria

PVC was subjected to a chemical modification aiming at r.placing the chlor.ne atoms by pyr.dine gr.ups via a homolytic r.ute. Pyr.dine gr.ups wer. peculiar.y affixed to the PVC matr.x via a car.on-car.on bond r.ther.than a car.onnitr.gen one. PVC was fir.t iodinated using the Conant-Finkelstein r.action, followed by the application of the homolytic conditions of Minisci to gener.te pyr.dinated PVC with a var.ing degr.e of substitution. The extent of substitution was not high; the r.action on 30% iodinated PVC affor.ed a degr.e of modification no gr.ater.than 3%.

关键词： Conditions of Minisci Iodinated PVC Pyr.dinated PVC

Changes in plant community diver.ity and abovegr.und biomass along with altitude within an alpine meadow on the Thr.e-r.ver.sour.e r.gion

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Chinese Science Bulletin 2012年第27期57卷 3573-3577页

作者： sa WenJun AN LiZhe sa Wei Institute of Botany Science School of Life SciencesLanzhou UniversityLanzhou 730000China School of Life Science Qinghai UniversityXining 810008China

The gr.ssland is an impor.ant component of ter.estr.al ecosystems and plays a significant r.le in biodiver.ity and ecosystem *** the pr.sent study,the changes of plant species diver.ity and abovegr.und biomass pr.ductivity wer. examined along with the altitude in natur.l alpine gr.ssland in the sour.e r.gion of thr.e r.ver. on the Qinghai-Tibetan *** exper.mental locations wer. selected with altitudes r.nging fr.m 3862 to 4450 m above sea level(a.s.l.).The r.sults indicated that Kobr.sia pygmaea meadow,Kobr.sia humilis meadow and salix cupular.s shr.b meadow had higher.indices of diver.ity and abovegr.und *** distr.bution of species diver.ity,r.chness and abovegr.und biomass showed similar.y unimodal patter.s acr.ss the altitude gr.dient with the highest indices appear.d at mid-altitudes *** changing tr.nd of species diver.ity,r.chness and evenness also showed significant unimodal patter.s with total abovegr.und biomass,and the highest species diver.ity occur.ed at inter.ediate level of *** r.sear.h would pr.vide a valuable r.fer.nce for.the pr.tection of gr.ssland biodiver.ity and maintaining of the gr.zing ecosystem function in the sour.e r.gion of the Thr.e r.ver..

关键词：植物群落多样性地上生物量海拔高度高寒草甸三江源地区植物物种多样性生态系统功能生物多样性

haLOMETHYLATION OF POLYSTYr.NE AND SUBSEQUENT PYr.DINATION VIA A HOMOLYTIC PATHWAY

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Chinese Jour.al of Polymer.Science 2006年第6期24卷 627-635页

作者： sad Moulay Nadia Mehdi Labor.toir. de Chimie-Physique Moléculair. et Macr.moléculair. Faculté des Sciences de l'Ingénieur Departement de Chimie IndustrielleUniversité de BlidaRoute de SoumaB. P. 270Blida 09000Algeria

Chlor.methylation of polystyr.ne （PS） with two differ.nt chlor.methylating systems methylal/thionyl chlor.de and par.for.aldehyde/tr.methylchlor.silane was studied. Soluble chlor.methylated polystyr.ne with a degr.e of substitution of 89% was obtained. The Conant-Finkelstein r.action on the chlor.methylated PS affor.ed soluble iodomethylated polystyr.ne with a degr.e of substitution as high as 96%. The r.action conditions of Minisci wer. employed to r.dically pyr.dinate PS via its iodomethylated der.vative. Polyelectr.lytes wer. for.ed which could be conver.ed to nor.al polymer. by tr.atment with a 20% aqueous solution of NaOH.

关键词： Chlor.methylated polystyr.ne Conditions of Minisci Iodomethylated polystyr.ne Pyr.dinated polystyr.ne.

r.sponse of photosynthesis,gr.wth,and acor. mass of pedunculate oak to diff er.nt levels of nitr.gen in wet and dr. gr.wing seasons

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Jour.al of For.str. r.sear.h 2023年第1期34卷 167-176页

作者： Kr.noslav Sever.saša Bogdan ŽeljkoŠkvor. Faculty of For.str. and Wood Technology University of ZagrebSvetošimunska 2510000 ZagrebCroatia

The objective was to examine the effects of optimal leaf nitr.gen levels>2.0%and suboptimal levels<2.0%,nitr.gen nutr.tion on net photo synthetic r.te,stem diameter.incr.ment,height gr.wth incr.ment and acor. mass of ... 详细信息

The objective was to examine the effects of optimal leaf nitr.gen levels>2.0%and suboptimal levelsr.gen nutr.tion on net photo synthetic r.te,stem diameter.incr.ment,height gr.wth incr.ment and acor. mass of pedunculate oak dur.ng 2010 in the absence of dr.ught str.ss and dur.ng 2011 under.the impact of moder.te dr.ught *** to the r.sults,moder.te dr.ught str.ss significantly r.duced net photo synthetic r.te,stem diameter.incr.ment and height gr.wth incr.ment,while acor. mass was not *** nitr.gen nutr.tion significantly r.duced the net photo synthetic r.te and stem diameter.incr.ment only in the wet year.acor. mass in both wet and dr. year.,while height gr.wth incr.ment was not significantly r.duced by suboptimal nitr.gen nutr.tion in either.*** r.sults indicate that optimal nitr.gen levels can stimulate photo synthetic r.te and stem diameter.incr.ment of pedunculate oak only in the absence of moder.te dr.ught ***,the r.sults show that moder.te dr.ught str.ss is a mor. dominant str.ssor.for.photosynthesis and gr.wth of pedunculate oak than suboptimal nitr.gen nutr.tion,while for.acor. development,it is the mor. dominant str.ssor.

关键词： Quer.us r.bur.L. Dr.ught str.ss Net photosynthic r.te Stem diameter.incr.ment Height gr.wth incr.ment Acor. mass

一种基于DTW-DP-GMM的工业机器人轨迹学习策略

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天津大学学报（自然科学与工程技术版） 2025年第1期58卷 68-80页

作者：肖洒陈旭阳叶锦华吴海彬福州大学机械工程及自动化学院福州350108 福建省特种智能装备安全与测控重点实验室福州350108

针对机器人示教编程过程中使用高斯混合模型(GMM)规划运动轨迹时存在的高斯分布个数难以选择、复现轨迹精度较低等问题,提出了一种复合的机器人运动轨迹学习策略.该策略包含动态时间规整(DTW)算法、高斯混合模型与道格拉斯-普克(DP)算法... 详细信息

针对机器人示教编程过程中使用高斯混合模型(GMM)规划运动轨迹时存在的高斯分布个数难以选择、复现轨迹精度较低等问题,提出了一种复合的机器人运动轨迹学习策略.该策略包含动态时间规整(DTW)算法、高斯混合模型与道格拉斯-普克(DP)算法.首先,针对示教过程中采集的多条轨迹在时间长度上存在差异的问题,采用DTW算法来统一示教轨迹在时域上的变化.其次,使用GMM算法对示教轨迹的特征进行提取,并利用高斯混合回归(GMr.算法将其重构为复现轨迹.在这个过程中采用DP算法来预估GMM算法的关键参数高斯分布的数量,与传统方法相比,能够简单直观地得到相对准确的参数值.利用DP算法对复现轨迹的数据点进行稀疏化并优化,不仅确保了机器人最终运动轨迹的精度,而且大幅减少了最终轨迹数据点的数量.最后,进行了不同形状的模拟焊接轨迹学习规划实验.结果表明:经由DTW对齐后的示教轨迹具有更加明显的运动特征,经过GMM-GMr.习输出的复现轨迹具有良好的表征结果;在使用GMM-GMr.法学习示教轨迹的过程中,采用DP算法可以有效预估高斯分布个数;经过DP算法稀疏化并优化的最终轨迹的平均位置误差均在0.500 mm以内,其最大误差可以控制在0.800 mm以内,可以满足焊接轨迹规划的精度要求,验证了该策略的有效性和优越性.

关键词：工业机器人示教编程高斯混合模型道格拉斯-普克算法动态时间规整轨迹复现

Ecor.gional height-diameter.models for.Scots pine in Tur.iye

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Jour.al of For.str. r.sear.h 2024年第6期35卷 49-61页

作者： Fadime sağlam Oytun Emr. sakici Depar.ment of For.st Engineer.ng Faculty of ForestryKastamonu University37150 KastamonuTurkey

Ecor.gion-based height-diameter.models wer. developed in the pr.sent study for.Scots pine(Pinus sylves-tr.s L.)stands in Tur.iye and included sever.l ecological factor. der.ved fr.m a pr.-existing ecor.gional classification *** data wer. obtained fr.m 2831 sample tr.es in 292 sample *** gener.lized height–diameter.models wer. developed,and the best model(HD10)was selected accor.ing to statistical ***,nonlinear.mixed-effects modeling was applied to the best *** r. for.the gener.lized height‒diameter.model(r.char.s function)modified by Shar.a and Par.on is 0.951,and the final model included number.of tr.es,dominant height,and diameter.at br.ast height,with a r.ndom par.meter.associated with each ecor.gion attached to the inver.e of the mean basal *** full model pr.dictions using the nonlinear.mixed-effects model and the r.duced model(HD10)pr.dictions wer. compar.d using the nonlinear.sum of extr. squar.s test,which r.vealed significant differ.nces between ecor.-gions;ecor.gion-based height–diameter.models wer. thus found to be suitable to *** addition,using these models in appr.pr.ate ecor.gions was ver. impor.ant for.achieving r.liable pr.dictions with low pr.diction er.or..

关键词： Tr.e height Nonlinear.mixed-effects modelling Nonlinear.sum of extr. squar.s method Ecor.gion Scots pine

Pr.ctices of backuping homomor.hically encr.pted databases

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Fr.ntier. of Computer.Science 2019年第2期13卷 220-230页

作者： sa WANG Yiwen ShaO Yungang BAO SKL Computer.Ar.hitectur. Institute of Computing Technology Chinese Academy of Sciences Beijing 100190 China Univer.ity of Chinese Academy of Sciences Beijing 100049 China

Ideal homomor.hic encr.ption is theor.tically achievable but impr.ctical in r.ality due to tr.mendous computing over.ead. Homomor.hically encr.pted databases, such as Cr.ptDB, lever.ge r.plication with par.ially homomor.hic encr.ption schemes to suppor. differ.nt SQL quer.es over.encr.pted data dir.ctly. These databases r.ach a balance between secur.ty and efficiency, but incur.consider.ble stor.ge over.ead, especially when making backups. Unfor.unately, gener.l data compr.ssion techniques r.lying on data similar.ty exhibit inefficiency on encr.pted data. We pr.sent Cr.ptZip, a backup and r.cover. system that could highly r.duce the backup stor.ge cost of encr.pted databases. The key idea is to lever.ge the metadata infor.ation of encr.ption schemes and selectively backup one or.sever.l columns among semantically r.dundant columns. The exper.mental r.sults show that Cr.ptZip could r.duce up to 90.5% backup stor.ge cost on TPC-C benchmar..

关键词： homomor.hic encr.ption secur.ty deduplication