CORC
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天文学 9 光学工程 7 光学 5
健康心理学 4 植物学 4 生态学 3
计算机科学技术基础学科::数据安全与计算机安全 3 主要研究方向::海洋生物学 2 基础心理学 2
应用心理学 2 环境科学 2 自然地理学 2
行为遗传学 2 计算机科学技术其他学科 2 计算机科学技术基础学科 2
计算机科学技术基础学科::计算机科学技术基础学科其他学科 2 Conservation genetics of L. decora: The nucleotide sequences from three chloroplast DNA (cpDNA) regions (the rpl16 intron, trnQ-5’rps16 intergenic spacer and rpl32-trnL intergenic spacer) and two nuclear gene (GAPDH and GBSSI) were selected to characterize the genetic structure and phylogeography of this species. Eleven populations were sampled across the distribution range of L. decora in China. Low levels of cpDNA genetic diversity were found in this species and within populations, with the identification of 2 haplotypes in a total of 2745 bp (cpDNA: π = 0.00102, Hd = 0.468, HT = 0.480), while the levels of genetic diversity revealed by the nuclear gene GAPDH and GBSSI (GAPDH: π = 0.00237, Hd = 0.773, HT = 0.807; GBSSI: π = 0.00167, Hd = 0.751, HT = 0.790) were relatively high, indicating that random losses of genetic polymorphisms from populations may have occurred recently. Relatively high genetic differentiation for both markers (cpDNA: GST = 0.899, FST = 0.893; GAPDH: GST = 0.309, FST = 0.432; GBSSI: GST = 0.274, FST = 0.263) were detected at the wide-species level. Two cpDNA haplotypes, twelve GAPDH haplotypes and ten GBSSI haplotypes were recovered, respectively. Almost every population except the population SP was fixed for one cpDNA haplotype, causing no variation within the populations. Several nuclear haplotypes were distributed widely in most populations. These results may be mainly explained by long-term fragmentation and the limited gene flow caused by geographic isolation among populations. The mismatch distribution analyses and neutrality tests provided no evidence for a recent population expansion in L. decora. The time of all GAPDH haplotypes coalesced to the most recent common ancestor was dated to between 0.46 (95% CI 0.14-0.89)-0.65 (95% CI 0.18-1.22)mya, which predates the LGM. In situ shrinking or extinction might have occurred to L. decora during the glacial ages and L. decora populations did not retreat to common refugia or migrated backwards. Based on the genetic diversity and uniqueness of the populations, conservation strategies are discussed for this endangered species.2. 1 GNSS interoperability signal performance analysis Signal is very important for the satellite navigation service, which determines the navigation accuracy. GPS and Galileo have made the MBOC signal as the baseline of interoperability signal, more specialists work on the interoperability signal design and performance analysis in recent years. As MBOC plays an important role in interoperability signal, the research of MBOC interoperability performance is useable. This paper introduced the basic theory of MBOC signal, analyze the correlation characteristics, the tracking accuracy, and multipath error of interoperability signal TMBOC and CBOC.(2)GNSS interoperability signal interference analysis.GNSS interoperability will take more visible satellites and navigation signals for users. The realization of GNSS interoperability is a process of multi-GNSS resource sharing, and union of signals from systems. So, monitoring the anti-interference and interference level of MBOC is an important work for the choice of future interoperability signal. This paper analyzed the spectrum separation coefficient, the code tracking interference coefficient, interference coefficient and equivalent carrier-to-noise ratio of TMBOC and CBOC signal. This paper also analyzes the Weil code and Random code performance. 1
人工智能 1 人工智能::人工智能其他学科 1 人工智能::人工智能理论 1
人工智能::机器翻译 1 人工智能::模式识别 1 人工智能::自然语言处理 1
养殖生态学 1 化学 1 固体力学 1
图书情报理论研究与信息社会学::数字图书馆研究 1 地球科学::海洋科学 1 地球科学::海洋科学::物理海洋学 1
地理学::自然地理学::资源评价,地理学::自然地理学::水文地理学及水资源 1 地质学::第四纪地质学 1 应用心理 1
植物生态学 1 模式识别与智能系统 1 水土保持学 1
流体力学 1 测绘工程 1 环境科学技术::环境科学技术基础学科::环境生态学 1
理学 1 生物学::动物学,农学 1 生物学::植物学::植物生态学,生物学::植物学::植物生理学 1
生物学::植物学::植物生理学 1 生物资源::生物传感器技术 1 生物资源::能源植物资源 1
电子、通信与自动控制技术::信息处理技术 1 第一研究方向 1 计算机应用::中国语言文字信息处理(包括汉字信息处理) 1
计算机应用::计算机应用其他学科 1 计算机科学技术基础学科::数据结构 1 计算机科学技术基础学科::算法理论 1
计算机视觉与模式识别 1 计算机软件::计算机软件其他学科 1 认知神经科学 1

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