简介：ChengdeCity,famousforitsculturalsightseeingtourismindustry,andislocatedinChina's"CapitalHolidayTourismCircle".Thislocationisadvantageous,becauseoftherecentboominChina'snationaltourismindustry.Thisindustryhasgonethroughseveralstructuralanddevelopmentchangeswithinthepastseveralyears.Aresultoftheserestructuringpatternsisthegreatchangesconcerningcompetitiveandcooperativerelationsamongtourismdestinations,whichhaveprecipitatedthedeclineofthetraditionalsightseeingpattern.NorthernChina's"CapitalHolidayTourismCircle"isoneofninekeyareaswithintheChinesetourismindustryunderdevelopmentduringtheEleventhFive-YearPlan.Inthepresentarticlethemethodof"DistanceDeclineofTheTouristFlow"wasusedtodefinetheflowoftouristsintheCapitalHolidayTourismCircleanditsinfluenceuponChengde'stourismspatialdistribution.3aspectswillbediscussed:(1)ThetransformationfromsightseeingtoleisuremarketsmakesthechangepossibleinChengde'stourismspatialpattern.(2)Thelocationadvantage(adjacenttoBeijingandTianjin)alsoleadstothechangeinChengdetourismspatialpattern.(3)Theestablishmentoffreewaysalsocontributestoagreatdegreesofchange.TherapiddevelopmentofleisuretourismmightleadtothechangefromnucleusmodeltoadiversifiedonewithinChengde'stourism.Specifically,Chengdeisdevelopingthetourismindustrywiththecentralheritageareaasthenucleusandthenorthernforest,pasture,southernmountain,andriversasitsperiphery.

简介：Heuristicisanimportantmethodtosolvetheshortestpathproblems.Itindicatesliterallylearningbyexperience,ormoregenerallyintheartificialintelligenceliterature,aheuristicisa“ruleofthumb”andassuchistheapproachusedbyalmostanyhumaninconductingasearch［1］。Inthecontextofcomputersearchalgorithms,heuristicimpliessimplesearchthroughspecificknowledge.Un_deraspecialfunction,ateverystepthesealg_orithmssearchthenodewithhighestscoreasthenextnodetobeextended.Themajoreffectofheuristicsearchisthatinsomewayitconstrainsthesearchspace.Theshortestpathalgorithmsbasedonheuristicincludescostingalgorithm［1］，branch_and_boundalgorithm［2，3］，greedyalgorithms［4～11］，hill_climbingalgorithms［1～3］，andA*algorithm［12～14］,etc.　　Amongtheknownshortestpathalgorithms,manyofthemusethegreedystrategiesasthesearchstrategiesandexplorehowtodesigndelicaterunningdatastructuresandsearchingalgorithms,soastoimprovetherunningefficiencyofsequentialshortestpathalgorithmsundertheuniformtimecomplexity.Forthetwobranchesoflosslessshortestpathalgorithms：labelsettingandlabelcorrectingalgorithms，expertshavesetforwardvariousrunningdatastructuresandrelatedliteraturesemergeendlessly.Refs.［15～19］havemadedetailedanalysisandcomparisonfortheshortestpathalgorithmspresentedbefore.Becausetherealnetworks,suchastransportationnetworks,telecommunicationnetworks,facilitynetworksandhydrographicnetworksdonotconcernnegativeweights,afamouslabelsettingalgorithmadoptinggreedystrategy,namelyDijkstra'salgorithm,hasattractedwideattentionandgotwidedisseminationandapplications.Dijkstra'salgorithmisthemostmatureshortestpathalgorithmtheoreticallyuptodate［8,16,20］andhasbecomethecrucialalgorithmforthenetworkanalysismodulesofmanylargeGISplatforms.Differentimplementationmethodshaveformedalargefami

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简介：ＳｐａｔｉａｌＤｉｓｔｒｉｂｕｔｉｏｎｏｆＥＬ２ＤｅｆｅｃｔｉｎＳｅｍｉ－ｉｎｓｕｌａｔｉｎｇＧａＡｓＲｕＱｉｏｎｇｎａ；ＬｉＧｕａｎｇｐｉｎｇａｎｄＨｅＸｉｕｋｕｎ（汝琼娜）（李光平）（何秀坤）（ＴｉａｎｊｎｇＥｌｅｃｔｒｏｎｉｃＭａｔｅｒｉａｌｓ...

简介：PopularregionalinequalityindexessuchasvariationcoefficientandGinicoefficientcanonlyrevealoverallinequality,andhavelimitedabilityinrevealingspatialdependenceorspatialagglomeration.Recentlysomemethodsofexploratoryspatialdataanalysissuchasspatialautocorrelationhaveprovidedeffectivetoolstoanalyzespatialagglomerationandcluster,whichcanrevealthepatternofregionalinequality.ThisarticleattemptstousespatialautocorrelationatcountyleveltogetrefinedspatialpatternofregionaldisparityinChinesenortheasteconomicregionover2000-2006(2001absent).Theresultindicatesthatthebasictrendofregionaleconomyisanincreasingconcentrationofgrowthamongcountiesinnortheasteconomicregion,andtherearetwogeographicalclustersofpoorercountiesincludingthecountiesinwesternLiaoningProvinceandadjacentcountiesinInnerMongolia,poorercountiesofHeihe,QiqiharandSuihuainHeilongjiangProvince.Thisarticlealsorevealsthatwecanusethemethodsofexploratoryspatialdataanalysisasthesupplementaryanalysismethodsinregionaleconomicanalysis.

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简介：<正>ThespatialchaosofBose-Einsteincondensatesinacigar-shapedtrapisstudied.Forasystemwithasteadycurrent,weconstructthegeneralsolutionofthe1st-orderequation.Fromtheboundednessconditionofthegeneralsolution,weobtaintheMelnikovfunctionpredictingtheonsetofchaos.Theunpredictabilityofthesystem’sdis-tributionofatomdensityisalsotheoreticallyanalyzed.Fora23Nasystemmeetingtheperturbationoondition,numericalsimulationsshowtheexistenceofchaos,whichisinaccordancewithouranalyticalresults.Numericalsimulationsofa87Rbsystemdissatisfyingtheperturbationconditionalsodemonstratethatthereexistschaosinthesystem.Thecasewithoutacurrentisalsoinvestigated.

简介：海洋的生物多样性响应改变的物理环境，随后的生态的变化以及人为的骚乱正在变化。在这研究，在situ的浮游植物样品在1999和2010的7月在Bering海收集了被分析获得在浮游植物社区动力学的这十年，和关联的开始和结束之间的浮游植物社区结构和空间时间的变化，环境因素被调查。5个部门，58个类和属于3个生态的组的浮游植物的153种类的一个总数被识别。绝大多数浮游植物为66.7%全部的种类和95.2%全部的丰富由硅藻财务组成了。就在空间程度和浮游植物样品类型的区别而言，在种类作文有微妙的变化，在在二之间的空间分发的在丰富和重要变化的大改变调查。当潜水艇山峰在Bering海盆被发现时，丰富山峰区域在白令海峡被定位。北方适度的硅藻是主导的植物群，它被广温性、寒冷水的硅藻随后代替。在Bering海的浮游植物社区不是一个单一的一致社区，但是深海洋的集合和浅海的集合创作了。深海洋的集合位于西北的太平洋和Bering海盆，由北方适度的种类统治了(Neodenticulaseminae，Thalassiothrixlongissima，Amphiprora严寒，Chaetocerosatlanticus，Thalassiosiratrifulta，等等)并且散布很广的种类(Thalassionemanitzschioides，Ch。compressus，Rhizosoleniastyliformis，等等)，并且由低丰富，甚至interspecies丰富分配，多样的主导的种类和高种类差异描绘了。浅海的集合在大陆人架和Bering海的斜坡上被散布并且主要由寒冷水的种类组成(Th。nordenski?ldii，Ch。furcellatus，Ch。socialis，Bacteriosirafragilis，等等)并且广温性、能在不同盐分之环的种类(L。danicus，Ch。curvisetus，Coscinodiscuscurvatulus，等等)，并且它被高丰富，不平的interspecies分配，突出的主导的种类和低种类差异描绘。在Bering海的种类作文和许多浮游植物的空间时间的变化被表�

简介：Thebasicmathematicmodels,suchasthestatisticmodel,thetime-serialmodel,thespatialdynamicmodeletc.,andsometypicalanalysismethodsbasedon3DCMareproposedanddiscussed.Afewtypicalspatialdecisionmakingmethodsintegratingthespatialanalysisandthebasicmathematicalmodelsarealsointroduced,e.g.Visualimpactassessment,dispersionofnoiseimmissions,basestationplanforwirelesscommunication.Inaddition,anewideaofexpectationoffurtherapplicationsandadd-in-valueserviceof3DCMispromoted.Asanexample,thesunshineanalysisisstudiedandsomehelpfulconclusionsaredrawn.

简介：Inthispaper,weusethedailyrangesoftheverticalmagneticintensityofapproximately76geomagneticstationsfromJanuary1,2008toDecember31,2010toanalyzethespatialandtemporalcharacteristicsofZranges.Theresultsaresummarizedasfollows:(1)Temporally,weuseregressiveanalysisandFFTanalysistoanalyzethedata.TheresultsshowthattheZcomponentdailyrangesofallstationshaveanobviouscyclicalvariation,thecomputedFourierspectraofalldatasetshaveclearlyresolvedtherequiredperiodicitiesinthedata,intheformofdistinctpeaksatdays365,183,22,and73,andthepowerspectraofday365isthehighestinallperiods.(2)Intermsofspatialvariation,thedailyrangesshownonlinearvariationwithlatitudeinChina.Theresultsshowtheexistenceofapointofinflexion(maximalvaluepoint)nearbyatabout25°N,thedailyrangesofZrisefrom15°~25°Nandhaveagoodlineardecreasevariationalongwith25°~50°N.(3)ComparedwiththespatialandtemporalvariationsofZdailyrangeswiththeSqcurrentinversion,wefoundthatthespatialandtemporalcharacteristicsofZrangesaredecidedmainlybythespatio-temporalevolutionoftheSqcurrentsystem.(4)IfthelatitudesofthemaximumamplitudesofvariationoftheverticalcomponentinthegeomagneticquietdaysareroughlytakenasthelatitudescorrespondingtothefociofSqoverheadcurrentsystem,wecanseethattheselatitudesoffocibecomehigherinsummer,arelowestinwinterandhighestduringEquinoxes,displayingconspicuousmonthlyanddailyvariations.Fortwosuccessivegeomagneticquietdays,thelatitudesoffocimayvarytendegrees.

简介：地理信息系统(GIS)逐渐地正在管理数据的很大的集合，一个因此集中的数据索引不能总是提供最可伸缩的解决方案。最近，p2p(P2P)网络为以一种完全分散的方式分享信息变得很流行。在这份报纸，新混合P2P空间索引网络(HPSIN)被建议，它把分布式的空铅树与基于的分布式的哈希值桌子(DHT)相结合维持询问效率和系统负担的弦网络平衡。另外，一个简单理论模型基于为HPSIN的打开的排队网络被建立。在模型，作为M/M/1排队处理器假定每个同伴系统的基本特征被捕获，并且平均质问延期的表示在靠近的形式被获得。理论分析和数字计算结果证明那在那里存在在效率和负担平衡之间的折衷的一个最佳点。由将开始索引水平ls的合适的值放为不同网络规模和询问率，HPSIN将完成因此，延期能使适应不同P2P应用程序环境的最小的全面询问。

简介：Abinaural-loudness-model-basedmethodforevaluatingthespatialdiscriminationthresholdofmagnitudesofhead-relatedtransferfunction(HRTF)isproposed.Astheinputofthebinauralloudnessmodel,theHRTFmagnitudevariationscausedbyspatialpositionvariationswerefirstlycalculatedfromahigh-resolutionHRTFdataset.Then,threeperceptualrelevantparameters,namelyinterauralloudnessleveldifference,binauralloudnesslevelspectra,andtotalbinauralloudnesslevel,werederivedfromthebinauralloudnessmodel.Finally,thespatialdiscriminationthresholdsofHRTFmagnitudewereevaluatedaccordingtojust-noticedifferenceoftheabove-mentionedperceptual-relevantparameters.AseriesofpsychoacousticexperimentswasalsoconductedtoobtainthespatialdiscriminationthresholdofHRTFmagnitudes.Resultsindicatethatthethresholdderivedfromtheproposedbinaural-loudness-modelbasedmethodisconsistentwiththatobtainedfromthetraditionalpsychoacousticexperiment,validatingtheeffectivenessoftheproposedmethod.

简介：在3D抵抗力倒置最小化答案的数字，在倒置的一个固有的问题，考虑的数据的数量不得不大，优先的限制需要被使用。关于一个地质的异例的程度的地质、地球物理的数据是重要优先的信息。我们在3D建议形状限制的使用电的抵抗力倒置。三加权的直角的向量(正常和二正切向量)被用来在异例的边界控制抵抗力差别。异例的边界上的异例和限制的空间形状因此被建立。我们在3D抵抗力倒置的客观功能合并了空间形状限制并且与空间形状限制构造了3D抵抗力倒置方程。随后，我们使用了抑制方向向量和3D抵抗力倒置的重量的基于优先的空间形状数据的数字建模。我们建立了在方向向量和重量之间的一个合理范围，并且验证了使用空间形状的可行性和有效性在减少过多的结构和答案的数字的优先的限制。我们使用了优先的空间地抑制形状的倒置方法在广州地铁定位含水土层。空间形状限制从渗透雷达数据的地面被拿。含水土层的地点和形状的倒置结果与钻倒置的数据，和数字同意解决方案显著地被减少很好。

简介：TotalconcentrationsofZninthesedimentsoftheoffshoreandintertidalareasofthewestcoastofPeninsularMalaysiawererecentlyreportedintheliteraturs.However,totalconcentrationsofmetalsinthesedimentsamplesdonotreflecttheportionorcarrierphasewhichisattributabletoanthropogenicactivitiesandthoseofnaturalorigins.Inthiswork,geochemicalfractionofZninthesedimentsofthesameareaswasstudiedandthepotentialuseofCVasanindicatorofZnpollutionwasdetermined.Thegeochemicalstudybyusingsequentialextractiontechniquerevealedtions,respectively,inthesedimentswhilemostofthetotalzincconcentrations(offshore:70%;intertidal:52%)foundinthesedimentscouldbemostlyduetonaturalorigins(nonresistantfraction).Thus,theZnlevelsintheStraitsofMalaccashouldnotposearisktotheliyingorganisms.BasedonSpearman'scorrelationcoefficients,thesourceofZncontaminationintheStraitsofMalaccawasmainlycontributedbytheintertidalcoastalarearatherthanoffshorearea.ThepresentstudyalsoindicatedthecoefficientofvariationcanbeusedasapotentialindicatoroftotalsummationofgeochemicalZnconcentrationsinthecoastalsedimentbutofdifferentgeochemicalofZnneedsfurthervalidation.

简介：在台湾海峡的有颜色的溶解有机物(CDOM)的吸收性质的空间、时间的可变性在夏天(到2006的8月的7月)和冬季被调查(从2006年12月到2007的1月)季节。在280nm的CDOM吸收系数(一280)从nearshore显示出一个减少的趋势到近海区域当时光谱在275295nm(S275295)显示出的波长之间计算的斜坡系数参数增加，减少的aromaticity的陈述语气和CDOM的分子的重量。一般水准280在冬季(1.47牡敳

简介：Theresearchisabouttheeffectofalayerofvaryingdensityofsea-bottomsedimentsonspatialcorrelationofsea-bottombackscattering.Therelationshipbetweenscatteringcrosssectionandspatialcorrelationisthatbackscatteringcrosssectiondecreasesquicklyandthespatialcorrelationbecomesstrongerastheincidentangleincreases.Therefore,thedensitydepthprofileisintroducedintosea-bottomhigh-frequencybackscatteringechomodel,whichisusedtosimulatesea-bottombackscatteringandcalculatethefunctionofspatialcorrelation.Theinfluenceofthedensitygradientonspatialcorrelationofsea-bottombackscatteringisinvestigatedbyanalyzingtherelationsbetweenverticalgradientofdensityandthescatteringcrosssection.Ascanbeseenfromthesimulationresults,theimpactofthedensitygradientonthespatialcorrelationisfoundmoresignificant.Whilethedensitygradientincreases,thescatteringcross-sectionandtheradiusofthespatialcorrelationbroaden,thespatialcorrelationbecomesstronger.Atthesametime,thescatteringcross-sectiondecreasesmorequicklyastheincidentangleincreases.

简介：ThecommunitycharacteristicsofmangrovesintheFutianNatureReserve,Shenzhen,Chinaaregivenbasedonsurveyingof33quadratsin4transectswhichstretchfromthehighertidalzonetothelowertidalzone.Theresultsshowthatthereare6communitytypesinthisarea:Kandeliacardelassociation,Avicenniamarinaassociation,Aegicerascorniculatumassociation,Kardeliacardel+Aegicerascorniculatumassociation,Aegicerascorniculatum+KandeliacandelassociationandAcanthusilicifoliusassociation.Kandeliacandel,AegicerascorniculatumandAvicenniamarinadominatethetypicalquadrats.Kandeliacandelcanbeseenatalmostallquadrats,Aegicerascorniculatumdistributesmostlytowardtheestuaryandthehighertidalzone,Avicenniamarinadistributesmostlytowardthebayandthelowertidalzone,BruguieragymnorrhizaoccasionallyoccurstowardtheEstuarywithoneorseveralindividuals,Acanthusilicifoliuswascommontowardthehighertidalzone,asanaccompanyingspecies,Derristrifoliatawascommoninmanymaturequadrats.Totally,6speciesofmangroveplantsand3speciesofsemi-mangroveplantsappearinthisresearcharea.Fromthehighertidalzonetothelowertidalzone,theaveragediameterandbasalareaofmangrovetreesincreasegradually.Accordingtotheresults,theAvicenniamarinadominatesinaveragediameterandbasalarea,andtheAegicerascorniculatumtreesareonthecontrary.Fromthetransect1tothetransect4,theimportancevalueofAvicenniamarina,BruguieragymnorrhizaandKandeliacandeldecreases,andAegicerascorniculatumincreases.Inthisarea,theKandeliacandelpopulationandAegicerascorniculatumpopulationaredevelopingpopulationswithmanyseedlingsandsaplings,buttheAvicenniamarinapopulationisinamaturestagewithfewseedlingsandnotsomanytotalindividuals.Accordingtothisresearch,wesupposethatAegicerascorniculatumshouldbedevelopedtowardtheestuaryandtheAvicenniamarinaassociationshouldbeprotected.

简介：Thispaperdealswiththedesignandperformanceanalysisofthetransmissionprecoderoptimizationformultiple-inputmultiple-output(MIMO)systemswithlimitedfeedbackofchannelstateinformation(CSI).Weassumethatthereceivercangetperfectchannelknowledgebychannelestimationwhilethetransmitteronlyhaspartialchannelknowledgefromlimitedfeedback.Wepresentaminimummeansquareerror(MMSE)criterionbasedcodebookconstructionalgorithmforMIMOpre-codedspatialmultiplexingsystemsunderaspecificaveragepowerconstraint.Theoptimaltransmitterstructureisemployedinthispaper.SimulationresultsshowthattheMMSEcriteriabasedcodebookconstructionalgorithmwithhybriddesignofpowerallocationandprecodingcanachievebetterperformancethanthatofequalpowerallocationbasedcodebookofpreviousresearch.

简介：Stimulatedemissiondepletion(STED)microscopyisoneoffar-fieldopticalmicroscopytechniquesthatcanprovidesub-diffractionspatialresolution.ThespatialresolutionoftheSTEDmicroscopyisdeterminedbythespeciallyengineeredbeamprofileofthedepletionbeamanditspower.However,thebeamprofileofthedepletionbeammaybedistortedduetoaberrationsofopticalsystemsandinhomogeneityofaspecimen’sopticalproperties,resultinginacompromisedspatialresolution.Thesituationgetsdeterioratedwhenthicksamplesareimaged.Intheworstcase,theseveredistortionofthedepletionbeamprofilemaycausecompletelossofthesuperresolutioneffectnomatterhowmuchdepletionpowerisappliedtospecimens.Previouslyseveraladaptiveopticsapproacheshavebeenexploredtocompensateaberrationsofsystemsandspecimens.However,itisdifficulttocorrectthecomplicatedhigh-orderopticalaberrationsofspecimens.Inthisreport,wedemonstratethatthecomplicateddistortedwavefrontfromathickphantomsamplecanbemeasuredbyusingthecoherentopticaladaptivetechnique.Thefullcorrectioncaneffectivelymaintainandimprovespatialresolutioninimagingthicksamples.

简介：Anintegratedmethodbasedonopticalanddigitalimageprocessingispresentedtosuppressspeckleindigitalholography.Aspatiallightmodulatorisadoptedtointroducerandomphasestotheilluminatingbeam.Multiplehologramsarereconstructedandsuperimposed,andtheintensityisaveragedtosmooththenoise.Theadaptivealgorithmbasedonthenonlocalmeansisdesignedtofurthersuppressthespeckle.Thepresentedmethodiscomparedwithothermethods.Theexperimentalresultsshowthatspecklereductionisimproved,andtheproposedmethodiseffectiveandfeasible.