简介:包含的28年的最好的轨道数据集缩放在西北的太平洋包括s−1弯屈的15.4m(R15)和热带气旋(TC)的s−1弯屈的25.7m(R26)的半径的参数,NCEP/NCAR分析数据集和扩大重建的海面温度(ERSST)数据集在这研究被采用。为在从1977~2004的西北的太平洋的热带气旋的尺寸参数的气候学以空间、时间的分布被调查。结果证明在西北的太平洋的TC的主要活动从7月到10月。在150°E的海洋西方上的TC谎言的一个多数,和一些TC能加强到Saffir-Simpson(S-S)范畴4,5。R15和R26趋于作为热带气旋增加加强。R15和R26的价值通常比在北方大西洋为在西北的太平洋的强烈TC是更大的。R15和R26在10月达到顶点,并且在10月,R15和R26前后减少它与在北方大西洋的案例不同。更小的R15s和R26s在西北的太平洋上发生在一个大范围,当更大的R15s和R26s主要从台湾岛在东方海洋躺着到在哪儿的菲律宾的岛时许多热带气旋在强烈系统发展。有R15或R26的参数平均拿的尺寸的热带气旋比变弱加强的很长时间,和弱热带气旋比增强率有更快变弱的率。从1977~2004,R15的年平均价值与年基本上增加;在28年的时期期间,由52.7km的R15增加的价值,而是R26不显然随着年变化。
简介:【内容摘要】真空断路器具有维护工作量小、断流容量大、重量轻、噪声低、易安装、适宜频繁操作等许多优点,在电力系统10kV-35 kV电压等级中逐渐取代了其它类型断路器,得到了广泛的应用。真空断路器是一种以气体分子极为稀少,分子间的平均自由行程很大,电子与分子相碰撞的机会极少,绝缘强度很高的真空空间为熄弧介质的新型断路器。
简介:Intheestimationofseismictendency,usingGutenberg-Richter¢sb-valueandusingHurstexponentaretwocom-monlyusedmethods.Basedonthefractalgeometryofearthquaketimeseries,wepointoutthatthesetwomethodscorrelatetoeachother.IntheperspectiveoffractionalBrownianmotion(FBM),anearthquakesequencewithb>3/4andthatwithb<3/4havedifferentdynamicproperties.
简介:WeusedearthquakecatalogsrecordedbyGuangdongSeismologicalNetworkfrom2008to2014toresolvethespatialvariationsofb-valuesinthecoastalareaofGuangdong,particularlyinthreekeyresearchareas(Yangjiang,Heyuan,andoffshoreNanaoIsland)withstrongseismicity.Ourresultsrevealedthatb-valuesexhibitedsignificantspatialvariations,andzoneswithlowb-valuescouldindicatethemostlikelyseismogenicareaoflargeearthquakes.Weobservedthreeclearlowb-valuepatchesintheoffshoreNanaoIsland.Wefoundadistincthighb-valuepeakatthedepthof11kmandtwominimumpeaksatabout14and7–8kmintheYangjiangarea.Theoverallb-valuesgenerallydecreasewithdepthintheHeyuanarea.Thespatialvariationsofb-valuesreflecttectonicanomalies;thatis,the‘low-high-low’distributionofb-valuesintheoffshoreNanaoIslandandtheYangjiangareamayindicatetheanomalyofthecrustalstructurewithaweaklayer.Theb-valuesofreservoir-inducedseismicityareobviouslylowerthanthatinducedbytectonism.Thisfindingindicatesthatthereservoirareaisgenerallyathighstressstateundertheconditionofhighporepressure.Weinferredthatlargeearthquakesmightbepronetooccurat10–12kmdepthintheoffshoreNanaoIsland,at12–15kmdepthintheYangjiangarea,andatthelowerpartoftheseismicactivityzoneintheHeyuanarea.Moreover,theupstreamareaoftheXinfengjiangreservoiristhemostlikelyareaoffuturelargeearthquakesintheHeyuanarea.
简介:IntroductionRegionalseismicitytriggeredbybigearthquakesaswellasattershocksinsourcezonecouldbedetectedduetothehighseismicmonitoringcapabilitytoday(Anderson,etal,1994;Bodin,Gomberg,1994;Caskey,Wesnousky,1997;Deng,Sykes,1996;Hill,etal,1993;King,etal,19...
简介:SequencevariationofpartialcytochromebgenesbetweentwoCoiliaspecies,C.ectenesandC.mystus,wasinvestigated.Ofthe402nucleotides,twenty-seven(6.72%)arepolymorphicandallaresynonymoussubstitutions.Atthethirdpositionsofgeneticcondonofcytochromebgene,thetwospeciesshowanextremeanti-Gbias(<4%)andapronouncedbiastowardsAandC(>68%).Thereisnoaminoacidsequencedivergencebetweenthepartialcytochromebgenesofthetwospecies,indicatingaclosegeneticrelationshipbetweenthem.Thek-2pgeneticdistanceofpartialcytochromebsegmentofthetwospeciesis0.072,suggestingthatthespecieswereseparated3.6Maago,inthemiddlePliocene.Ourresultrevealsthatthecytochromebgeneisanappropriatemarkerforstudiesofpopulationgeneticstructuresandphylogeographicpatternsofthetwospecies.