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81.
现代汉语二合复句内分句语气同类组配是主体,异类组配是次要的。前后分句语气异类组配的使用频率具有一定的倾向性:陈述与疑问/祈使/感叹的组配〉疑问/祈使/感叹之间的两两组配;陈述+疑问/祈使/感叹〉疑问/祈使/感叹+陈述。陈述语气与疑问/祈使/感叹共享特征的数量都多于疑问、祈使、感叹两两语气之间共享特征的数量,因此前者是优势组配。疑问/祈使/感叹居前时通常要满足三个条件,居后时不受此限制,因此疑问/祈使/感叹居后是优势组配。 相似文献
82.
近年来,大数据浪潮兴起,大数据产业保持高速发展态势,大数据应用推进势头良好。政府数据作为价值密度高、涉足广度宽的数据资源,已成为各国争相创新开发的重要资产。但是长期以来,关于政府数据开发利用的理论研究却被忽视,如何科学有效地进行政府数据开发和利用已成为当前需要迫切关注的问题。文章系统总结了当前主要发达国家政府数据开发利用的政策措施和探索实践,以及通过梳理分析我国政府数据开发利用的政策体系和发展现状,尝试构建政府数据开发利用的过程机制模型,并提出:加强顶层立法,落实制度保障;扩大数据来源,提升数据质量;统一汇聚开放,深化行业应用;确立认证许可,明晰授权机制;创新开发模式,明确收益分配;推动试点先行,探索可行经验;强化技术支撑,保障数据安全等政策建议,以期为进一步推动政府数据开发利用提供决策参考。 相似文献
83.
The most fantastic optical phenomena in the Earth''s upper atmosphere are the auroras. They are highly informative indicators of solar activity, geomagnetic activity, upper atmospheric structures and dynamics, and magnetospheric energetic particles. An area where the geomagnetic field differs significantly from the expected symmetric dipole, such as at the South Atlantic Anomaly, where the magnetic field intensity is low, gives rise to stronger precipitation of energetic particles into the upper atmosphere. Impact excitation and the subsequent airglow emissions exhibit aurora-like dynamic signatures. Nomenclatures of nonpolar aurora or equatorial auroras are similar to those used with the polar auroras owing to their similar excitation mechanisms. This paper provides an overview of the knowledge and the challenges concerning auroral activity at the South Atlantic Anomaly, or more generally, at the negative magnetic anomaly. We emphasize systematic investigation of the equatorial auroras to reveal the temporal and spatial evolution of the magnetic anomaly and the behaviour of energetic particles in near-Earth space. 相似文献
84.
Honglei Lin Zhiping He Wei Yang Yangting Lin Rui Xu Chi Zhang Meng-Hua Zhu Rui Chang Jinhai Zhang Chunlai Li Hongyu Lin Yang Liu Sheng Gou Yong Wei Sen Hu Changbin Xue Jianfeng Yang Jie Zhong Xiaohui Fu Weixing Wan Yongliao Zou 《国家科学评论(英文版)》2020,7(5):913
Chang’E-4 landed in the South Pole-Aitken (SPA) basin, providing a unique chance to probe the composition of the lunar interior. Its landing site is located on ejecta strips in Von Kármán crater that possibly originate from the neighboring Finsen crater. A surface rock and the lunar regolith at 10 sites along the rover Yutu-2 track were measured by the onboard Visible and Near-Infrared Imaging Spectrometer in the first three lunar days of mission operations. In situ spectra of the regolith have peak band positions at 1 and 2 μm, similar to the spectral data of Finsen ejecta from the Moon Mineralogy Mapper, which confirms that the regolith''s composition of the landing area is mostly similar to that of Finsen ejecta. The rock spectrum shows similar band peak positions, but stronger absorptions, suggesting relatively fresh exposure. The rock may consist of 38.1 ± 5.4% low-Ca pyroxene, 13.9 ± 5.1% olivine and 48.0 ± 3.1% plagioclase, referred to as olivine-norite. The plagioclase-abundant and olivine-poor modal composition of the rock is inconsistent with the origin of the mantle, but representative of the lunar lower crust. Alternatively, the rock crystallized from the impact-derived melt pool formed by the SPA-impact event via mixing the lunar crust and mantle materials. This scenario is consistent with fast-cooling thermal conditions of a shallow melt pool, indicated by the fine to medium-sized texture (<3 mm) of the rock and the SPA-impact melting model [Icarus 2012; 220: 730–43]. 相似文献
85.
This study contributes to our understanding of the complex issues inherent in dealing with the heterogeneity of current high school science classrooms, by reporting on in-depth interviews with 38 experienced biology teachers. Analyses of teachers' responses revealed complex and occasionally counter-intuitive relationships among: (a) their perceptions of what was distinctive about their school, its biology program, or their students; (b) their allocation of class time; (c) their efforts to individualize instruction and meet the needs of a heterogeneous student population; (d) their student outcome goals; and (e) the methods they used to evaluate student progress. Thus, for example, of the 9 teachers who cited the diversity of their students. 4 also commented on their poor motivation, but another 4 also commented on their high motivation. In addition, teachers reported using a similar range of instructional formats but for different reasons, depending on the characteristics of their students (e.g., cooperative learning groups used to compensate for poor attention spans, to challenge bright students, and to foster social tolerance). Discussion of these findings addresses several points of relevance for science education, teacher preparation, and curriculum reform. © 1996 John Wiley & Sons, Inc. 相似文献
86.
采用自编问卷对北京市5538名幼儿园教师进行调查,调查发现真实性评价方法被广泛应用,过程性评价与终结性评价兼顾是普遍样态;幼儿发展评价工作实效性较好,与教师认知态度显著相关,公办园、6-15年教龄与本科(含)以上学历教师认知态度与工作实效性更好;教师认为内部评价主体更加重要。调查发现乡村教师认知与工作实效性有待提升、城区教师需重视评价结果运用等问题,并提出了针对性的对策与建议。 相似文献
87.
88.
A series of item analyses of the CAK-C was conducted for a sample of 155 educable mentally retarded children. The probability of a correct response was found to differ from task to task, and there was evidence that the order of difficulty of the tasks for this sample resembled that for nonretarded children. The probabilities of the two incorrect responses were generally not equal, and the choice of one or the other incorrect response showed some relation to CA, MA, and IQ, particularly the last two variables. 相似文献
89.
Kaufman's critique of our article was based on a misunderstanding of our purpose and procedures. This reply clarifies those points and suggests further areas of concern regarding the McCarthy Screening Test. 相似文献
90.
专利价值的评估指标体系及模糊综合评价 /FONT /P 总被引:20,自引:2,他引:20
专利是企业一项重要的无形资产,有效评估其价值对企业具有重大意义。基于专利价值的时效性、不确定性和模糊性,本文尝试建立一个科学的专利价值评估指标体系,用层次分析法计算指标的权重,再用模糊综合评价法得出专利的现时货币价值量,以期为企业专利价值评估提供一种新思路。 相似文献