简介：以应用为切人点，介绍用VB开发基于SQLSERVER的C／S软件中的系统配置、前后台连接、数据访问等实际问题的解决思路及实例。对数据库控件、数据库访问对象及ODBC三种数据库访问方法进行比较分析，得出在气象业务C／S应用系统开发中，ADO数据访问方法是一种较佳的选择。

简介：引言当前我国正积极筹备加入世界贸易组织(WTO),一旦加入,中国的一些农产品将受到国外农产品的严重冲击.在这种形势下,除了依靠政府制定有利于产业结构调整,稳定农民收入的政策外,生产者还应更加注重资源的合理利用,达到生态、经济、社会和生产的可持续发展.

简介：Netprimaryproduction(NPP)ofcroprepresentsthecapacityofsequestratingatmosphericCO_2inagro-ecosystem,anditplaysanimportantroleinterrestrialcarboncycling.BylinkingtheCrop-CmodelwithclimatechangescenarioprojectedbyacoupledGCMFGOALSviageographicalinformationsystem(GIS)techniques,cropNPPinChinawassimulatedfrom2000to2050.ThenationalaveragedsurfaceairtemperaturefromFGOALSisprojectedtoincreaseby1.0℃overthisperiodandthecorrespondingatmosphericCO_2concentrationis535ppmby2050undertheIPCCAIBscenario.Withaspatialresolutionof10×10km~2,modelsimulationindicatedthatanannualaverageincreaseof0.6TgCyr~(-1)(Tg=10~(12)g)wouldbepossibleundertheAIBscenario.TheNPPinthelate2040swouldincreaseby5%(30TgC)withinthe98×10~6hm~2croplandareaincontrastwiththatintheearly2000s.AfurtherinvestigationsuggestedthatchangesintheNPPwouldnotbeevenlydistributedinChina.AhigherincreasewouldoccurinamajorityofregionslocatedineasternandnorthwesternChina,whileaslightreductionwouldappearinHebeiandTianjininnorthernChina.ThespatialcharacteristicsofthecropNPPchangeareattributedprimarilytotheunevendistributionoftemperaturechange.

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简介：Long-termintegrationsareconductedusingtheSpectralAtmosphericModel(referredtoasSAMIL),whichwasdevelopedintheLaboratoryforNumericalModelingforAtmosphericSciencesandGeophysicalFluidDynamics(LASG)intheInstituteofAtmosphericPhysics(IAP),withdifferentresolutionstoinves-tigatesensitivityoftheMadden-JulianOscillation(MJO)simulationstothemodel'sresolution(horizontalandvertical).Threeresolutionsofthemodel,R15L9,R42L9andR42L26,withidenticalphysicalprocesses,allproducedthebasicobservedfeaturesoftheMJO,includingthespatiotemporalspace-timespectraandeastwardpropagation.Nofundamentaldifferencesamongthesesimulationswerefound.ThisindicatesthatthemodelresolutionisnotadeterminingfactorforsimulatingtheMJO.Detaileddifferencesamongthesemodelingresultssuggest,however,thatmodelresolutioncansubstantiallyaffectthesimulatedMJOincertainaspects.Forinstance,atalowerhorizontalresolution,highfrequencydisturbanceswereweakerandthestructuresofthesimulatedMJOwerebetterdefinedtoacertainextent.AhigherverticalresolutionledtoamorerealisticspatiotemporalspectrumandspatialdistributionofMJOprecipitation.Meanwhile,increasingthemodel'sresolutionimprovedsimulationoftheclimatology.However,increasingtheresolutionshouldbebasedonimprovingthecumulusparameterizationscheme.

简介：利用^14C的比度测定年代是一项划时代的工作，对推动考古学及古气候研究起了决定性的作用。这项工作是从Libby开始的，他创建了^14C年代学的理论基础和实验方法。^14C年代学的原理是放射性^14C只存在于大气和一切与大气处于交换状态的含碳物质中。一旦该物质脱离交换状态，^14C放射性不再得到补偿，只会按衰变规律降低。这样就可以按下列公式算出该物质的年龄，即：

简介：一座大楼城市的流动上的密度的效果与RNGκ用一个CFD模型被调查-ɛ骚乱闭合计划。有不同的造的27个案例是密度参数(例如，大楼和街峡谷纵横比)数字地被模仿。当大楼的密度参数变化，不同流动政体出现。当街峡谷相对狭窄、高时，在垂直方向的二个相反旋转的旋涡被产生。沿着街的风速被大楼的长度主要影响。然而，以一座单个大楼的密度参数发现或概括街峡谷流动的特征是很困难的。这是因为复杂流动模式由于旋涡结构和旋涡数字的变化出现。平均卷的涡度大小是很好的指示物尽管有流动的强壮的相关性，在大楼的密度参数的变化上反映流动特征。平均卷的涡度大小是大楼的长度和街峡谷宽度的强壮的功能的多线性的回归表演。大楼的长度的增加减少街峡谷的涡度流动，当时，在街上，峡谷宽度增加的增加涡度。

简介：2004台风Aere的降水的结构的特征从测量国家航空学空间管理(NASA)的使命(TRMM)的热带降雨用高分辨率的数据被分析。台风的特征在它的发展的不同阶段变化，这被发现。分析降水分发的不对称的引起，从环境预言(NCEP)分析的国家中心的数据被用来计算水蒸汽流动向量的垂直积分。因为这个过程，结果显示出那，与成双台风的循环的唯一的现象一起，在东方台风的北方面的空气电流和它的南部的方面的西南的空气水流在搬运水起一个联合作用蒸汽。而且，它的运输效果在开发的不同阶段极大地变化，显示出为这台风进程的水来源的怪癖。由重降水和水蒸汽流动的一个最大值的区域描绘区域的台风传送对流的分布，以及在台风的发展的不同阶段的强壮的上升运动区域不同。水蒸汽流动和垂直运动的不一致的分发引起台风降水的不均匀的分发。

简介：“粒径××，粒子数××，粒普××，PM2．5浓度××”，通过电子触摸屏，工作人员每隔3S就能采集一次空气中可吸入颗粒物（PM2．5和PM10）的浓度和粒径分布。3月29日我国首台可实时检测可吸入颗粒物浓度及粒径分布的仪器（LD310和LD320）在京通过了专家鉴定。

简介：BasedonChina’sobservationaldatain1951-1990,afterminimizingthepossiblebiasescausedbystationrelocationandurbanheatisland,thespatialandtemporaldistributionsoftrendsformaximumandminimumtemperaturesarestudied.Theresultsshowthatincreasingtrendsofmaximumtemperaturesareintheareaswestto95°E,andnorthtotheHuanghe(Yellow)River,whiledecreasingtrendsexistineasternChinasouthtotheYellowRiver.MinimumtemperaturesaregenerallyincreasingthroughoutChina,withdominantwarmingtrendsatthehigherlatitudes.Thisresultedinveryobviousdecreasingtrendsindiurnaltemperatureranges.Theperiodiccyclesareconsistentbetweenthemaximumandminimumtemperatures,butasymmetrictrendsareveryobvious.Thesignificantincreaseofminimum(nighttime)temperaturesreflectstheevidenceofenhancementofgreenhouseeffect.Furtheranalysisshowsthatthechangesofmaximumandminimumtemperaturesaremainlyrelatedtosunshinedurationandatmosphericwatervaporcontent.

简介：介绍了基于B／S结构的网上考试系统应用于气象部门的理论研究，并分析了系统总体结构，提供了一种应用SQL数据库以及ASP编程实现的网络考试系统，详细阐述了科目管理、随机生成试卷等模块的设计与实现，以及相关数据库表的结构。

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简介：Thesimplelinearrelationshipbetweenclear-skyplanetaryandsurfacealbedocanbeadoptedforcertainaccuracy.Therearedifferentparameterizationschemesofatmosphericcorrectionfordifferentretrievalmodels.Inthispaper,severalrepresentativeretrievalmodelsarecomparedandtestedwithobservationaldatafromHEIhebasinFieldExperiment(HEIFE)inwesternChina.Someevaluationsandsuggestionsonimprovementareproposedformodelswhichwouldbemoreapplicabletoplateauandaridareas.

简介：Itispresentedthatthereisapumpingeffectatitsbaseinthedevelopmentprocessofacumulus.Inthestrongeststageofcumulusdevelopment,thepumpingismainlyproducedbythebuoyanceatthebase,andmaybetakenasthefirstapproximationoftheascendingspeedatthebase.Theresultsofnumericalcalculationsandsimulationsoffourobservedradarechoesshowthatasthefirstapproximation,theheightofair-masscumulusmaybesimulatedbyHaltinermodelintheabsenceofob-servedascendingspeedsatthebase,andtheHaltinermodelcanbecharacterizedbythesensitivityofthecumulusdevelopmenttothevirtualtemperatureexcessoverenvironmentatthebase.

简介：ThisworkinvestigatesthedistributionofhighwindsaboveBeaufortscale6intheoffshorezonesofChinausinghigh-resolutionsatellitemeasurements.AnumericalexperimentiscarriedoutinordertofindouttheeffectsofTaiwanIslandontheformationofstrongwinds.Theanalysisindicatesthatthedistributionofhighwindoccurrenceissimilartothatoftheaveragewindvelocityinwinter.Highwindstendtobeanchoredinspecialtopographicalregions,suchastheTaiwanStrait,theBashiChannelandthesoutheastcoastofVietnam.HighwindsoccurmuchmorefrequentlyoverthewarmerthanthecolderflankofKuroshiofrontasitmeandersfromTaiwantoJapan.Thefrequencyofhighwindsdecreasesdrasticallyinspring.TheTaiwanStraitmaintainsthelargesthighwindoccurrence.Besides,highwindsremainfrequentintheBashiChannel,thesoutheasttipofTaiwanIslandandthewarmerflankofKuroshiofront.Insummer,highwindsgenerallyoccurinfrequentlyexceptoverabroadregionoffthesoutheastcoastofVietnamnear10°Nandthefrequencytheredecreasesfromsouthwesttonortheast.HighwindsaroundTaiwanIslandpresentnearaxisymmetricdistributionwithlargerfrequencyalongsoutheast-northwestdirectionandsmallerfrequencyalongsouthwest-northeastdirection.Thedominantdirectionofhighwindsexhibitsacounterclockwisecirculationsurroundingtheisland.Thefrequencyofhighwindsincreasesrapidlyinautumnandalmostrepeatsthedistributionthatappearsinwinter.ThesimulationresultssuggestthattheeffectsofTaiwanIslandtopographyonhighwindsvarywithseasons.Inwinter,topographyisthemajorcauseofhighwindsinthesurroundingoceaniczones.HighwindsinbothTaiwanStraitandthesoutheastcorneroftheislanddisappearandthefrequencydecreasesgraduallyfromsouthtonorthwhentheterrainisremoved.However,insummer,highwindfrequencyderivedfromtwosimulationswithandwithoutterrainisalmostidentical.Weattributethisphenomenontothefactorswhicharerespon

简介：1引言2001年12月6日,707-C波段测风雷达仰角驱动电路出现故障.通过分析判断,并对仰角驱动电路部分和机械部分进行检查,找出了发生故障的原因,同时也为该雷达的维修维护积累了宝贵的经验.

简介：1雷达显示的方位角度值与实际方位不符1.1故障现象通电以后,继电器吸合,角度指示出现三次数值,第一次复零,第二次是粗同步机的读数,第三次是正常角度值.摇动方位手轮,天线正常驱动,角度值也能按规律变化.但是,从开机后的方位角度显示以及后来驱动天线转动所显示的方位角度值都是错误的,不是雷达真正的空间方位角度值.

简介：ThedistributionofmonthlymeanerrorofNMCmodelforecastsanditsseasonalvariationareinvesti-gated.Theratioofmonthlymeanerrortostandarddeviationisusedheretofindoutthattheregionwhereacorrectionofsystematicerrorisneededandappropriateismainlyinlowlatitudes.Theimprovement,afterthemodel’sverticalresolutionandsomephysicalparameterswerechangedfromApril1985,isinvestigated,andtheNMCoperationalmodelforecastshavealsocomparedwiththoseofECMWF.

简介：随着浙江省各地对人影业务的需求日益提高，人影作业量逐年增加，这对浙江如何科学管理人影业务提出了新挑战。基于B／S模式建设一套面向省市县的人影业务管理系统，解决了人影业务操作规范化，管理标准化、科学化，信息数据化，信息口径统一化等问题，一定程度上提高了工作效率，促进了人影业务现代化发展的目的。另外，系统还具备对业务工作实时监管和弹药安全审批等功能，增强了人影安全生产的监管能力。

简介：TheoreticalstudyanddevelopmentofaduallinearpolarizationweatherradarinChinaarebrieflypresented.Alsodiscussedarethepotentialusesofthenewradarsysteminimprovingtheaccuracyofarealrainfallmeasure-mentsandanalysingthespacialstructureofstormsanddistributionofhydrometecrsincloudsbasedontheradarobservationaldatafromthefieldexperimcntsduringthesummersof1987—1989.TheresultsindicatethataC-banddualpolarizationweatherradar,afterconsideringthemicrowaveattenuationcorrection,maybeemployedtoquantitativelymeasurerainfallandtomonitorheavyrainandfloodeventsandbecomesanimpor-rantmeanstostudystormstructure.