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51.
数学的发现与数学的论证是数学的两大重要内容,如果没有数学的发现则论证就成了无源之水,无本之木;如果没有论证,命题的真假就不得而知,则发现就失去了意义。阐述了几何学中的升维类比与发现,一是命题的发现,二是论证的思想方法的发现。 相似文献
52.
近年来,随着我国教育改革的不断深化实践,教育也越来越重视对人的创新精神和创造能力的培养。独特的创新精神是推动一个人不断向前发展的动力,对于艺术设计行业而言,创新是成为一个合格的设计师必须要拥有的能力。本文基于当前艺术设计教育过程中对学生创新意识的培养情况,结合艺术设计对学生创新能力的培养要求,对艺术设计创新人才教育的培养模式进行深入的探讨。 相似文献
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Wei Ren Tang Li Qiuzhi Qu Bin Wang Lin Li Desheng Lü Weibiao Chen Liang Liu 《国家科学评论(英文版)》2020,7(12):1828
Atomic clocks with cold atoms play important roles in the field of fundamental physics as well as primary frequency standards. Operating such cold atom clocks in space paves the way for further exploration in fundamental physics, for example dark matter and general relativity. We developed a space cold atom clock (SCAC), which was launched into orbit with the Space Lab TG-2 in 2016. Before it deorbited with TG-2 in 2019, the SCAC had been working continuously for almost 3 years. During the period in orbit, many scientific experiments and engineering tests were performed. In this article, we summarize the principle, development and in-orbit results. These works provide the basis for construction of a space-borne time-frequency system in deep space. 相似文献
55.
Yanhua Qu Chunhai Chen Ying Xiong Huishang She Yong E Zhang Yalin Cheng Shane DuBay Dongming Li Per G P Ericson Yan Hao Hongyuan Wang Hongfeng Zhao Gang Song Hailin Zhang Ting Yang Chi Zhang Liping Liang Tianyu Wu Jinyang Zhao Qiang Gao Weiwei Zhai Fumin Lei 《国家科学评论(英文版)》2020,7(1):113
Known as the ‘third polar region’, the Qinghai-Tibet Plateau represents one of the harshest highland environments in the world and yet a number of organisms thrive there. Previous studies of birds, animals and humans have focused on well-differentiated populations in later stages of phenotypic divergence. The adaptive processes during the initial phase of highland adaptation remain poorly understood. We studied a human commensal, the Eurasian Tree Sparrow, which has followed human agriculture to the Qinghai-Tibet Plateau. Despite strong phenotypic differentiation at multiple levels, in particular in muscle-related phenotypes, highland and lowland populations show shallow genomic divergence and the colonization event occurred within the past few thousand years. In a one-month acclimation experiment investigating phenotypic plasticity, we exposed adult lowland tree sparrows to a hypoxic environment and did not observe muscle changes. Through population genetic analyses, we identified a signature of polygenic adaptation, whereby shifts in allele frequencies are spread across multiple loci, many of which are associated with muscle-related processes. Our results reveal a case of positive selection in which polygenic adaptation appears to drive rapid phenotypic evolution, shedding light on early stages of adaptive evolution to a novel environment. 相似文献
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Cong Liu Feng An Paria S M Gharavi Qinwen Lu Junkun Zha Chao Chen Liming Wang Xiaozhi Zhan Zedong Xu Yuan Zhang Ke Qu Junxiang Yao Yun Ou Zhiming Zhao Xiangli Zhong Dongwen Zhang Nagarajan Valanoor Lang Chen Tao Zhu Deyang Chen Xiaofang Zhai Peng Gao Tingting Jia Shuhong Xie Gaokuo Zhong Jiangyu Li 《国家科学评论(英文版)》2020,7(1):84
Complex oxides with tunable structures have many fascinating properties, though high-quality complex oxide epitaxy with precisely controlled composition is still out of reach. Here we have successfully developed solution-based single-crystalline epitaxy for multiferroic (1-x)BiTi(1-y)/2FeyMg(1-y)/2O3–(x)CaTiO3 (BTFM–CTO) solid solution in large area, confirming its ferroelectricity at the atomic scale with strong spontaneous polarization. Careful compositional tuning leads to a bulk magnetization of 0.07 ± 0.035 μB/Fe at room temperature, enabling magnetically induced polarization switching exhibiting a large magnetoelectric coefficient of 2.7–3.0 × 10−7 s/m. This work demonstrates the great potential of solution processing in large-scale complex oxide epitaxy and establishes novel room-temperature magnetoelectric coupling in epitaxial BTFM–CTO film, making it possible to explore a much wider space of composition, phase, and structure that can be easily scaled up for industrial applications. 相似文献
57.
根据《技术创新》课程的性质及功能,提出了课题研讨式课内教学和技术创新实践式课外教学交叉配合的《技术创新》课程教学模式。在转变教育观念的基础上,提出了《技术创新》课程全程多方位成绩考核模式。 相似文献
58.
基于网络的教学管理实践与思考 总被引:1,自引:1,他引:0
基于网络的教学管理具有涉及人员广泛、影响深刻、易于实践与检验的特点,因而可以做为建设数字化校园的突破口。本文以青岛大学教务在线的实践为例,探讨了高等学校实现在线教务管理的步骤、方法及应注意的问题,通过实践效果肯定了在线教务管理对教学管理工作的积极影响,指出了深化数字化校园建设中应进一步解决的问题。 相似文献
59.
"朱子民本思想与当代"学术研讨会,于2007年5月12日在安徽省黄山市召开,与会专家学者对朱子民本思想及其当代价值、朱子理学、朱子思想的历史影响、朱子其人及故里等方面的问题,进行了热烈而又深入的探讨,提出了一些新见解、新观点,进一步拓宽了朱子学研究的视野。 相似文献
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