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毫米波云雷达功率谱密度数据的检验和在弱降水滴谱反演中的应用研究
刘黎平 LIU Liping,谢蕾 XIE Lei, CUI Zhehu
大气科学 , 2014, DOI: 10.3878/j.issn.1006-9895.2013.12207
Abstract: 本文首先利用数值模拟的方法,分析了利用毫米波云雷达功率谱密度反演雨滴谱时,降水粒子米散射效应、空气湍流、空气上升速度等对雨滴谱和液态水含量等参数反演的影响;建立了功率谱密度处理及其直接反演雨滴谱、液态水含量、降水强度和空气上升速度的方法;并利用2012年7月在云南腾冲观测的二次弱降水数据,采用毫米波雷达和Ku波段微降水雷达观测的回波强度、径向速度垂直廓线以及780m高度上的功率谱密度对比的方法,以及毫米波云雷达观测的780m高度上功率谱密度、回波强度与地面雨滴谱计算得到的这些量的对比方法,分析了毫米波雷达数据的可靠性;并将780m高度上毫米波雷达反演的雨滴谱与地面雨滴谱数据进行了对比,分析了毫米波雷达反演的雨滴谱的准确性;分析了毫米波雷达回波强度偏弱的原因,讨论了该高度以下降水对毫米波雷达衰减的影响。结果表明:空气湍流对弱降水微物理参数反演影响不大,而空气上升速度和米散射效应均对反演结果有一定影响;毫米波雷达观测到的径向速度和功率谱密度与微降水雷达比较一致,回波强度的垂直廓线的形状与微降水雷达也比较一致,但毫米波雷达观测的回波强度偏弱;与雨滴谱计算值相比,毫米波雷达观测的低层的回波强度也偏弱,天线上的积水是造成毫米波雷达回波强度变弱的主要原因。毫米波雷达观测的低层的功率谱密度与地面雨滴谱观测的数据形状比较一致,但有一定的位移。毫米波雷达反演的雨滴谱与地面观测的谱型和粒子大小也比较一致。这些结果初步验证了毫米波雷达观测的功率谱密度及其反演方法的可靠性。
Genetic diversity and differentiation of two ecotypes of Leymus chi-nensis populations in microhabitat--Allozyme analysis
微生境下羊草两种生态型种群的遗传多样性及遗传分化——等位酶分析

CUI Ji Zhe,

生态学报 , 2000,
Abstract: Leymus chinensis (Trin.) Tzvel.is a rhizome grass species,which has two ecotypes,a gray green type and a yellow green type,in the south of the Songnen Plain of China.Levels of allozyme diversity and genetic differentiation were assessed for 14 allozyme loci in 7 populations of the gray green type and 2 populations of the yellow green type (a total of 271 individuals). Leymus chinensis maintained relatively high genetic variation at the ecotype,population and species levels as compared with the average plant species.Significant differences of genetic diversity and genetic differentiation were found between the gray green and yellow green ecotypes.Percentage of polymorphic loci,mean number of alleles per locus and expected heterozygosities between the gray green type and the yellow green type were 67.3% and 57.1%,2.2 and 1.9,0.348 and 0 298 respectively.The means of genetic distance were 0.18 between the ecotypes,0 045 and 0 099 within the gray green type and the yellow green type respectively.While the means of genetic identity were 0 836 between the types,those within the gray green type and the yellow green type were 0 956 and 0 914 respectively.
对流性降水云辐射特性研究
王小兰,程明,
气象 , 2005, DOI: 10.7519/j.issn.1000-0526.2005.9.001
Abstract: 结合mm5模式和三维微波辐射传输模式,对2002年7月22~23日发生在湖北宜昌附近一次中尺度强降水过程中的强降水中心的对流性降水云的微波辐射特性进行了模拟,模拟结果表明:mm5模式可以较好地模拟此次降水过程;云中各微物理量的含量和分布对上行微波辐射亮温有重要影响;就物理方法而言,选用适当的云廓线,是利用微波信息反演降水的关键。
洋面上层状性降水云数值模拟研究
,刘锦丽,程明
气象 , 2005, DOI: 10.7519/j.issn.1000-0526.2005.4.002
Abstract: 利用改进后的双参数层状性降水云模式,对洋面上层状性降水云进行了数值模拟研究。模拟结果表明:对于洋面上较厚的层云降水机制为冰相降水粒子的融化导致的,但降水增长与大陆上层状云不同,主要是在0℃层以下的暖区中进行的。在0℃层以上的负温度区域,几乎不存在液态雨滴。
Genetic Differentiation in Leymus chinensis Populations Revealed by RAPD Markers Ⅱ. Statistics Analysis
羊草种群遗传分化的RAPD分析Ⅱ.RAPD数据的统计分析

CUI Ji-Zhe,

生态学报 , 2002,
Abstract: Leymus chinensis (Trin.)Tzvel., which is one of rhizome grass species, has two ecotypes in the Songnen Plain,including a gray green type and a yellow green type. The levels of genetic diversity and genetic differentiation based on RAPDs were assessed among seven populations of the gray green type and two populations of the yellow green type (a total of 105 individuals). Fifteen 10-mer primers screened from seventy Operon's primer series were used to amplify RAPD fragments using a standard RAPD protocol. The number of amplified fragments and the percentage of polymorphic loci were different among nine populations. Populations that belong to the yellow green type possessed fewer amplified fragments (<90) and lower percentage of polymorphic loci(<50%)than that of the gray green type (>100 and >70% respectively). Genetic diversity based on RAPD phenotypic or genotypic frequencies was calculated using seven published methods by the statistical package RAPDISTANCE. The genetic diversity level in the yellow green type was lower than that in the gray green type. F_ IS value previously estimated with codominant markers, e.g.allozymes for the same population was used to estimate the null-allele frequencies for putative RAPD loci corrected for potential deviations from Hardy-Weinberg equilibrium. Shannon's information index and Nei's index of genetic diffferentiation were used to partition diversity within and among population components, and 37.6% or 35.7% of the variation detected with RAPDs was partitioned among populations. Genetic identity between the populations of two types were both on 0.8, while the genetic indentity within the gray green populations was above 0.9. The results achieved by the methods of either allozymes previously adopted or RAPDs revealed the same genetic pattern of variation. These results at the DNA level were parallel to those at the protein level. At both the protein and DNA levels, genetic polymorphism was higher in the populations of the gray green type than that in the yellow green populations.
Analysis on Relationship between Incidence of Acute Myocardial Infarction and Meteorology in Toutunhe District of Urumqi
乌鲁木齐头屯河区急性心肌梗塞发病率与气象关系的分析

Wang Shangtong,Cui Hu,
王尚桐
,

气候与环境研究 , 1999,
Abstract: Season characteristic of myocardial infarction's occuring and five kinds of climate are analyzed based on 168 cases of acute myocardial infarction from Xinjiang Steel and iron Company Hospital during 17 years from 1979 to 1996 and meteorological data. Winter and spring are considered to be seasons when myocardial infarction frequently occurs. Among the five kinds of climate the high air pressure-low temperature kind and the low air pressure-high temperature one are two kinds of climate when the incidence is highest, while the incidence is lowest during the low air pressure-low temperature kind of climate.
快速中值滤波方法及其在Doppler雷达资料处理中的应用
,程明,乌秋力,王柏忠
高原气象 , 2005,
Abstract: 提出了一种适用于Doppler雷达信号处理的快速中值滤波方法,与传统方法相比,它的特点是考虑了相邻中值滤波窗口内信号数据的相关性。在滤波过程中,由于该方法保留了前面滤波窗口内数据的排序信息,作为下一个滤波窗口内数据排序的参考,减少了当前滤波窗口内比较运算的次数,因此,提高了运算效率。我们将该种方法应用于Doppler雷达信号处理中,进行了3点、5点和7点中值滤波试验。结果表明,5点中值滤波较为适用于Doppler雷达信号处理,它既较好地保留了Doppler雷达信号,又有效地滤除了随机脉冲噪声。同时,由于Doppler雷达观测特点,对于雷达信号不宜进行方位中值滤波。
多普勒雷达实时反射率因子垂直廓线观测研究
史锐,程明,,何会中,刘朝晖
气象 , 2005, DOI: 10.7519/j.issn.1000-0526.2005.9.008
Abstract: 使用2002年6~7月长江中游地区宜昌s波段多普勒雷达在两次大范围混合性强降水过程中部分时段体积扫描强度数据以及周边100km范围内的7个雨量计整理成10min记录一次的雨量资料,分析了实时雷达反射率因子垂直廓线的特征。研究表明:反射率因子垂直廓线可反映出所选区域上空零度层亮带高度位置、回波的垂直变化规律等信息,以此分析降水的类型、云中粒子的发展变化;从雷达连续体扫得到的中、低仰角对应高度上的实时反射率因子垂直廓线的变化规律、ppi图像上对应雨量站点上空的回波变化情况及10min记录一次的地面雨量的变化趋势对比来看,发现三者能很好地统一起来,可用来较细致地分析降水云体的变化,有利于在无地面雨量计的地区分析降水量的大小、确定降水类型、估测降水的发展;对无亮带、反射率因子值较大而且越低仰角值越大的反射率因子垂直廓线的区域,对应地面上常有对流性强降水出现。
长江流域多普勒雷达回波强度资料对比分析
史锐,程明,,王柏忠
气象 , 2004, DOI: 10.7519/j.issn.1000-0526.2004.11.006
Abstract: 利用2002年夏季长江中下游外场试验中几对双多普勒天气雷达资料,对比分析了同一时间、同一位置的s波段与c波段雷达的cappi和部分ppi回波强度资料。分析结果显示,宜昌和荆州雷达回波强度统计分布一致性较好,合肥、马鞍山、无为三部多普勒雷达回波强度统计分布一致性相对较差。回波强度资料的散点图表明,不同雷达回波强度资料之间的相关性较低。另外进一步证实c波段雷达在大范围降水区域需要进行降水的衰减订正。
用云和辐射传输模式研究对流性降水云微物理及辐射特性
黄容,程明,,王柏忠,何会中
气象 , 2004, DOI: 10.7519/j.issn.1000-0526.2004.3.002
Abstract: 利用中国气象科学研究院的三维对流云模式模拟了1998年发生在我国武汉地区的特大暴雨过程中的对流云。在模拟云的成熟阶段,模拟结果和地面最大降水量实况及热带测雨卫星trmm(tropicalrainfallmeasuremission)的降水雷达pr(precipitationradar)的零度层高度和降水粒子达到的高度较接近。将该云物理模式的输出结果输入到liu的三维辐射模式的输入场,模拟了以trmm的微波成像仪tmi(trmmmicrowaveimager)的扫描角为入射角,频率为85.5ghz和37.0ghz的星载微波辐射仪接受到的亮温,模拟的结果表明云中各微物理量的分布对上行微波辐射的影响较大。
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