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The distribution of titanium abundance on the lunar surface is important knowledge for lunar geologic studies and future resource utilization.In this paper,we develop a preliminary model based on"ground truths"from Apollo and Luna sample-return sites to produce a titanium abundance map from Chang’E-1 Imaging Interferometer(IIM) images.The derived TiO2 abundances are validated with Clementine UVVIS results in several regions,including lunar highlands neighboring the Apollo 16 landing site,and high-Ti and low-Ti maria near the standard site of Mare Serenitatis(MS2) .The validation results show that TiO2 abundances modeled with Chang’E-1 IIM data are overestimated for highlands(~0.7 wt.%) and low-Ti maria(~1.5 wt.%) and underestimated for high-Ti maria(~0.8 wt.%).  相似文献   

3.
Using the spherical harmonic (SH) function model and the dual frequency GPS data of 139 International GPS Service (IGS) stations for July 15 of 2000, the global ionospheric total electron content (TEC) is calculated and the basic method is investigated. Here, preliminary results are reported and the problems and difficulties to be solved for using GPS data to determine the global ionospheric TEC are discussed.  相似文献   

4.
通过对白化微分方程解的指数函数特性的分析,提出原始灰序列的归一化映射规则,使非等间距灰预测模型NGM(1,1)适应一般灰序列,灰预测精度也大大提高;这亦解决了含负值灰序列预测的理论问题,拓宽了灰色预测理论,最后给出了两个验证性算例。  相似文献   

5.
Sub 16 is a substitution line with G. hirsutum cv. TM-1 genetic background except that the 16th chro-mosome (Chr. 16) is replaced by the corresponding homozygous chromosome of G. barbadense cv. 3-79, and T586 is a G. hirsutum multiple gene marker line with 8 dominant mutation genes. The R1 gene for anthocyanin pigmentation was tagged in Chr. 16 in T586. The objective of this research was to screen SSR markers tightly linked with R1 by using the F2 segregating population containing 1259 plants derived from t...  相似文献   

6.
高时空分辨率遥感影像的反演可有效解决南方云雨地区的数据缺失问题。本文以广西典型丘陵山地为试验区,利用时空自适应反射率融合模型(Spatial and Temporal Adaptive Reflectance Fusion Model,STRAFM)和增强型时空自适应反射率融合模型(Enhanced Spatial and Temporal Adaptive Reflectance Fusion Model,ESTRAFM)两种融合算法,选取小范围的国产环境减灾卫星(HJ-1 CCD)和中分辨率成像光谱仪(Moderate-resolution Imaging Spectroradiometer,MODIS)数据,比较分析两种融合算法所生成的高空间分辨率影像的优劣。与真实HJ-1 CCD的红、近红外(Near-infrared,NIR)波段影像相比,STRAFM和ESTRAFM预测影像在空间分布上均具有较好的一致性,R值均为极显著相关,差分图像98.94%以上像元反射率差值小于0.1,平均绝对差值(Average Absolute Difference,AAD)、平均差值(Average Difference,AD)、标准差(Standard Deviation,SD)均较小,融合效果好。与STRAFM相比较,ESTRAFM融合算法对真实HJ-1CCD影像的细节捕捉能力更强,高低反射率区域没有明显缩小或放大现象,破碎地物边界更清晰,不存在斑块。ESTRAFM预测影像与真实HJ-1 CCD红、近红外波段影像的相关性均高于STRAFM,相关系数(Pearson Correlation Coefficient,R)分别为0.930, 0.885。ESTRAFM预测影像与真实HJ-1 CCD影像差异小于STRAFM,其差分影像的AD、AAD、SD分别为-0.005、0.013、0.017。  相似文献   

7.
To identify useful genes from wild rice which have been lost or weakened in cultivated rice has become more and more important for modern breeding strategy. In this study, a BC4 population derived from 94W1, an acces-sion of common wild rice (Oryza rufipogon Griff.) from Dongxiang in Jiangxi Province of China, as the donor, and a high-yielding Indica cultivar (O. sativa L.), "Guichao 2", as the recipient, was used to identify quantitative trait loci (QTL) associated with yield and its components. Based on the analysis for the genotype of BC4F1 population with 87 SSR markers distributed throughout the genome and investigation of the plant height, yield and yield components of BC4F2, a total of 52 QTLs, were detected. Of 7 QTLs associated with grain yield per plant, 2 QTLs on chro-mosome 2 and chromosome 11 for grain yield, explaining 16% and 11% of the phenotypic variance respectively, were identified. The alleles from Dongxiang common wild rice in those two loci could increase the yield of "Guichao 2" by 25.9% and 23.2% respectively. The QTL on chromosome 2 increasing grain yield of cultivar is actually a major gene, which did not coincide with any previously published QTLs in rice.  相似文献   

8.
[目的]黑龙江省是中国重要的林业省份之一,也是受林火危害最严重的地区之一.通过遥感数据获取森林火点信息,充分了解近年来黑龙江省林火发生的时空分布格局,探索林火发生规律.[方法]根据黑龙江省2001—2018年MODIS(分辨率成像光谱仪)遥感图像的MCD64A1火烧迹地产品数据集,提取林火火点信息,结合历史火灾记录资料...  相似文献   

9.
为利用新一代欧洲太空局SAR系统Sentinel-1A卫星获取大面积地震变形数据,对其监测模式和数据特点进行研究,给出针对TOPSAR成像干涉数据处理的拼接方法,并利用Sentinel-1A数据获取尼泊尔"4·25"地震区域约160 km×180 km的地表形变。结果显示,地震导致的雷达视线向相对变形最大达2 m。  相似文献   

10.
The HJ-1A satellite was successfully launched on September 6, 2008. The inclusion of a HyperSpectral Imager (HSI) as one of the payloads of the HJ-1A Satellite is a major milestone in the field of the remote sensing in China. It is also the first Fourier transform imaging spectrometer routinely used to acquire scientific data from a satellite orbiting Earth. This paper briefly introduces the basic imaging theories of the spatially modulated Fourier transform imaging spectrometer, and then discusses the theoretical analysis and algorithms of spectrum reconstruction. Results of the operational spectrum reconstruction for the raw data of the HJ-1A satellite Fourier transform HSI are presented. At present, the algorithms and processing flow have been used successfully in the Ground Data Processing System (GDPS) built by the China Center for Resource Satellite Data and Applications (CRESDA).  相似文献   

11.
Sub 16 is a substitution line with G. hirsutum cv. TM-1 genetic background except that the 16th chromosome (Chr. 16) is replaced by the corresponding homozygous chromosome of G. barbadense cv. 3-79, and T586 is a G. hirsutum multiple gene marker line with 8 dominant mutation genes. The R 1 gene for anthocyanin pigmentation was tagged in Chr. 16 in T586. The objective of this research was to screen SSR markers tightly linked with R 1 by using the F2 segregating population containing 1259 plants derived from the cross of Sub 16 and T586 and the backbone genetic linkage map from G. hirsutum×G. barbadense BC1 newly updated by our laboratory. Genetic analysis suggested that the segregation ratio of red plants in the F2 population fit Mendelian 1:2:1 inheritance, confirming that the red plant trait was controlled by an incomplete dominance gene. Preliminary mapping of R 1 was conducted using 237 randomLy selected F2 individuals and JoinMap v3.0 software. Then, a fine map of R1 was constructed using the F2 segregating population containing 1259 plants, and R 1 was located between NAU4956 and NAU6752, with only 0.49 cM to the nearest maker loci (NAU6752). These results provided a foundation for map-based cloning of R 1 and further development of cotton cultivars with red fibers by transgenic technology. Supported by National Natural Science Foundation of China (Grant No. 30730067) and Programme of Introducing Talents of Discipline to Universities (Grant No. B08025)  相似文献   

12.
哈茨木霉(Trichoderma harzianum)是优良的生物防治真菌,能产生抗生性聚酮化合物(polyketides).目前没有关于催化木霉聚酮化合物合成的聚酮合成酶(polyketide synthase,PKS)的相关编码基因的报道,这限制了对聚酮化合物代谢合成途径的研究.该研究通过融合PCR技术获得哈茨木霉的聚酮合成酶pkst-1基因的编码区序列,成功构建了RNAi介导的pkst-1基因沉默表达载体,使pkst-1基因的表达量在mRNA水平上显著降低.pkst-1基因失活使转化子发酵液产生了类似基因敲除的抑菌效果,降低了哈茨木霉抑菌能力,研究表明pkst-1基因编码催化抗生性聚酮化合物合成的关键酶.此外,RNA干扰技术在研究中的成功应用为哈茨木霉或其它丝状真菌的次级代谢合成途径相关基因的功能鉴定提供新的研究思路.  相似文献   

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