简介：1994年4、5月间,我部会同海军海洋测绘研究所,在福建某海区,首次使用新近研制的多功能差分GPS测绘自动化系统(以下简称差分GPS系统)进行1:1万沿岸水深测量定位试验,同时投入T2002/DI3000/GRE4a全站式电子速测仪系统(以下简称全站仪系统)配合定位试验。从定位精度、定位自动化程度、工作效率到成果质量方面,都取得了令人满意的效果,为沿岸测量1:1万乃至更大比例尺的水深图工作带来了新的生机和活力。正如GPS定位系统在中、近海测量和全站仪系

简介：Inthisstudy,familiesofselectedpopulationforgrowth(SP_BWT),selectedpopulationforwhitespotsyndromevirus(WSSV)resistance(SP_RW),Bohaiwildpopulation(WP_BH)andHuanghaiwildpopulation(WP_HH)ofF.chinensiswereconstructedthroughartificialinseminationandwiththestandardizedprocedureoflarvaerearing.Growthandsurvivalperformancewerestudiedamongfourpopulationsaftera70dayscommontest.Theresultsshowedthatthemaximumleastsquaremeanofbodyweightwas17.50ginSP_BWTwhiletheminimumwas13.03ginWP_HH.ComparedwithWP_BH,bodyweightofSP_BWTincreasedby23.41%(P<0.01)andthatofSP_RWby12.20%(P>0.05).BodyweightsofSP_BWTandSP_RWweresignificantlyhigherthanthatofWP_HH,whichincreasedby34.31%(P<0.01)and22.10%(P<0.05),respectively.ThemeanAGRoffourpopulationswas0.19,0.18,0.17and0.16gd-1,respectively.Coefficientofvariationofbodyweightamongfourpopulationswashigh,whichrangedfrom32.67%to35.25%.Sucharangeshowedthattherewasthepotentialityforfurtherimprovementinselectedpopulations.Coefficientofvariationofsurvivalrateamongfourpopulationswaslow,varyingbetween3.20%and5.90%.Thedifferenceofsurvivalwashighlysignificant(P<0.01)betweenSP_BWTandWP_BH,andsignificant(P<0.05)betweenSP_RWandWP_BH.However,nosignificantdifferenceamongotherpopulations(P>0.05)wasobserved.Differentgrowthperformanceswerealsoobservedamongdifferentfamiliesineachpopulation.Thebodyweightof798Ffamilywasthehighest.Theabsolutegrowthrate(AGR)was0.25gd-1,150%higherthanthatofthelowestone,0.1gd-1in807Ffamily.Survivalrateoffamiliesamongfourpopulationswasdifferent.Thehighestwas94.74%,andthelowestwas71.88%.