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排序方式: 共有104条查询结果,搜索用时 15 毫秒
61.
大气平均作用温度Ta是地表温度遥感单窗算法中一个关键的参数,利用2008~2011年全国123个探空站点资料,针对大气水汽量的垂直分布特征,分析了利用近地层气温T0估算大气有效平均温度的可行性;进一步分析了T0和Ta之间的相关性,建立了适合我国地区大气平均温度估算的最佳模型Ta=44.97098+0.80512 T0,模型的决定系数R2为0.859,均方根误差为4.198 K。通过对44幅HJ|1B/IRS热红外图像地温反演的敏感性分析,结果表明:模型估算的Ta用于地表温度反演时的误差为1.734 K;当大气透射率τ很小时,模型估算的Ta误差对地温反演很敏感,较小的估算误差会给地温反演带来很大的误差;随着大气透射率τ的增加,Ta的估算误差对地温反演的敏感性逐渐降低。 相似文献
62.
Due to their highly branched structure and the large number of functional groups hyperbranched polymers possess unique properties that make them interesting for uses in a wide variety of applications. Some of the most widely investigated hyperbranched polymers are the polyesters based on 2,2-bis(methylol)propionic acid. In this paper we present the results of characterization studies of hyperbranched polyesters based on 2,2-bis(methylol)propionic acid which show that they are very complex products with a multidimensional distribution of various properties. The influence of the synthesis conditions on the structure and molar-mass characteristics of hyperbranched polyesters as well as the findings that allow a thorough understanding of the structure-property relationships are reviewed in detail. 相似文献
63.
十屋断陷层序地层特征与生储盖组合 总被引:2,自引:0,他引:2
十屋断陷经历了早期断陷和晚期消亡两大发育阶段,依据不整合面及对应的整合面,可划分出2个超层序。4个层序,分别与构造演化阶段相匹配,层序A为断陷早期形成,层序B为断陷中期产物,层序C与断陷后期相当,而层序D是断陷向坳陷转化阶段形成,同时依据基准面旋回与次级不整合面,建立起年代地层格架及基准面变化曲线。系统地划分了各层序的体系域,各体系域的生储盖分析结果表明,低水位,高水位体系域具有较好的储集条件,水进体系域则具备良好的烃和封盖条件。之间相互组合形成了十屋断陷4个生储盖组合。 相似文献
64.
Kabir MA Kaminska J Segel GB Bethlendy G Lin P Della Seta F Blegen C Swiderek KM Zoładek T Arndt KT Sherman F 《Yeast (Chichester, England)》2005,22(3):219-239
Eukaryotic chaperonins, the Cct complexes, are assembled into two rings, each of which is composed of a stoichiometric array of eight different subunits, which are denoted Cct1p-Cct8p. Overexpression of a single CCT gene in Saccharomyces cerevisiae causes an increase of the corresponding Cct subunit, but not of the Cct complex. Nevertheless, overexpression of certain Cct subunits, especially CCT6, suppresses a wide range of abnormal phenotypes, including those caused by the diverse types of conditional mutations tor2-21, lst8-2 and rsp5-9 and those caused by the concomitant overexpression of Sit4p and Sap155p. The examination of 73 altered forms of Cct6p revealed that the cct6-24 mutation, containing GDGTT --> AAAAA replacements of the conserved ATP-binding motif, was unable to suppress any of these traits, although the cct6-24 allele was completely functional for growth. These results provide evidence for functional differences among Cct subunits and for physiological properties of unassembled subunits. We suggest that the suppression is due to the competition of specific Cct subunits for activities that normally modify various cellular components. Furthermore, we also suggest that the Cct subunits can act as suppressors only in certain states, such as when associated with ATP. 相似文献
65.
The urban morphology is regarded as one of the main reasons for urban heat island (UHI). However, its effect on UHI in city-scale urban areas has seldom been examined. In this paper, we presented a rule-based regression model for investigating the nonlinear relationship between land surface temperature (LST) and urban morphology represented by building height, building density and sky view factor (SVF) across different dates in 2005. Results found that an urban morphology of medium building height and lower density significantly yielded higher LST variation levels, whereas the lowest LST variation levels occurred in high-rise and high-dense building arrays. Compared to building height, building density had a stronger influence on LST. Medium SVF values produced the lowest LST, whereas the largest and smallest SVF values produced the highest LST. Results also showed how rule-based regression model offer great performance in detecting the nonlinear mechanisms of LST as well. 相似文献
66.
The relationship between land surface temperature (LST) and Normalized Difference Vegetation Index (NDVI) associated with urban land‐use type and land‐use pattern is discussed in the City of Shanghai, China using data collected by the Enhanced Thematic Mapper Plus (ETM+) and aerial photographic remote sensing system. There is an apparent correlation between LST and NDVI from the visual interpretation of LST and NDVI contrasts. Mean LST and NDVI values associated with different land‐use types are significantly different. Multiple comparisons of mean LST and NDVI values associated with pairings of each land‐use type are also shown to be significantly different. The result of a regressive analysis shows an inverse correlation relationship between LST and NDVI within all land‐use polygons, the same to each land‐use type, but correlation coefficients associated with land‐use types are different. An analysis on the relationship between LST, NDVI and Shannon Diversity Index (SHDI) shows a positive correlation between LST and SHDI and a negative correlation between NDVI and SHDI. According to the above results, LST, SHDI and NDVI can be considered to be three basic indices to study the urban ecological environment and to contribute to further validation of the applicability of relatively low cost, moderate spatial resolution satellite imagery in evaluating environmental impacts of urban land function zoning, then to examine the impact of urban land‐use on the urban environment in Shanghai City. This provides an effective tool in evaluating the environmental influences of zoning in urban ecosystems with remote sensing and geographical information systems. 相似文献
67.
东营凹陷下第三系低位域沉积及非构造圈闭 总被引:6,自引:6,他引:6
低位域是一个层序地层学概念,即发育在I型层序界面之上、初次水泛面之下的,常由盆底扇、斜坡扇和低位楔状体组成的体系域。由于控制低位域发育的坡折带类型不同,低位域的沉积体构成也就有所不同。北部陡坡断裂坡折带发育以冲积扇、小型低位三角洲、近岸水下扇和浊积扇为特征的低位域;东部东营三角洲沉积坡折带,发育以斜坡扇、低位三角洲和水下扇为特征的低位域;南部缓坡带,低位域以低位三角洲和低位滨浅湖相沉积为主。在这些低位域中,发育了不同类型的非构造圈闭,北部和南部坡折带为超覆型地层圈闭,东部沉积坡折带发育岩性圈闭。经过对这些圈闭的精细描述和初步评价,认为含油气前景比较乐观,有望为东营凹陷非构造圈闭勘探作出重要贡献 相似文献
68.
基于MODIS 影像数据的劈窗算法研究及其参数确定 总被引:12,自引:0,他引:12
劈窗算法是目前由热红外遥感数据获取陆面温度的主要方法。在介绍劈窗算法的一般表现形式的基础上, 我们推导出适合于MOD IS 影像数据的劈窗算法。大气透过率和地表比辐射率是求解地表温度的两个关键参数。由于MOD IS 图像分辨率较低,MOD IS 像元主要由水面、植被和裸土3种地物类型构成, 故可依据这3 种地物的构成比例确定地表比辐射率。从遥感影像上反演大气的水汽含量, 再根据大气水汽含量与大气透过率的关系计算出大气透过率。最后将文中推导的劈窗算法用于江苏省地表温度的反演。反演出来的地表温度图显示出明显的地表温度空间差异、城市热岛效应和不同的地物类型。 相似文献
69.
南阳凹陷北部坡折带隐蔽油气藏勘探 总被引:13,自引:4,他引:9
坡折带是沉积学和层序地层学中的一个极其重要的概念。对南阳凹陷北部坡折带进行了系统的研究,阐述了坡折带的形成机制及坡折带控制下的层序的基本类型、体系域构成模式,并对坡折带控制下的隐蔽油藏的成藏条件进行了研究。勘探结果表明,南阳凹陷坡折带控制下的隐蔽油气藏具有较大的勘探潜力。图5参4 相似文献
70.
以北京市Landsat TM为数据源,提出了一种新的地表温度光谱分解模型(Temperature Unmixing with Spectral,TUS),以期将地表温度的空间分辨率提高到30 m.首先,基于线性光谱混合模型获得地表组分的丰度值.然后,基于温度/植被指数选取典型端元的地表温度.最后,综合地表组分的比辐射率数据实现地表温度的分解.结果表明,TUS模型能够有效地提高地表温度的空间分辨率,反映不同地表组分地表温度的空间差异性,平均绝对误差(MAE)和均方根误差(RMSE)分别为1.25 K和2.27 K,非常适合于复杂地表覆盖地区的地表温度降尺度处理. 相似文献