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11.
一氧化氮对植物生长发育的作用 总被引:1,自引:0,他引:1
一氧化氮(NO)是一种气体信号分子,参与调控植物的许多重要生理过程,介绍了NO信号分子的发现,内源NO的产生以及NO对植物生长发育的作用。 相似文献
12.
谷茂春 《甘肃广播电视大学学报》2005,15(4):41-44
介绍了内涵增长率和可持续增长率的含义,通过实例数据对比验证了在内涵增长率、可持续增长率和某种实际增长率情况下销售增长对企业资本结构和长期发展的影响。得出结论企业必须选择适当的发展速度,可持续增长率是企业发展速度的参照。 相似文献
13.
基于点云数据的复杂型面实体建模研究 总被引:1,自引:1,他引:0
陈雪芳 《苏州市职业大学学报》2006,17(2):64-66
文章针对复杂型面产品的特点,从工业产品设计的实际应用出发,提出将正向设计的尺寸和定位关系设计方法和逆向设计的复杂曲面设计方法有效结合起来,基于点云数据实现产品的实体模型重建。以摩托车覆盖件为例,利用逆向工程软件从点云数据中提取和重构特征曲线与曲面,然后将这些几何元素信息在正向设计系统中结合特征建模方法创建整体三维CAD模型。 相似文献
14.
Oliver Dieckmann 《Journal of Cultural Economics》1996,20(4):297-320
Shortcomings of neoclassical growth theory and growth accounting are viewed as a challenge for cultural economics. Recently, new growth theory has introduced several growth determinants and has closed the gap between theoretical and empirical research. Whether this development leaves space for cultural determinants in explaining economic growth is in the center of this paper. The theoretical analysis shows how an endogenous growth model can be used to explain the impact on economic growth of cultural determinants. The empirical part uses indices from cross-cultural studies to extend recent cross-country growth regressions. Among other Hofstedes uncertainty avoidance index is shown to be significantly correlated with economic growth.Discussion paper presented at the 9th international conference of the Association for Cultural Economics, Boston, May 8–11, 1996. 相似文献
15.
As the number and diversity of distributed Web databases on the Internet exponentially increase, it is difficult for user
to know which databases are appropriate to search. Given database language models that describe the content of each database,
database selection services can provide assistance in locating databases relevant to the information needs of users. In this
paper, we propose a database selection approach based on statistical language modeling. The basic idea behind the approach
is that, for databases that are categorized into a topic hierarchy, individual language models are estimated at different
search stages, and then the databases are ranked by the similarity to the query according to the estimated language model.
Two-stage smoothed language models are presented to circumvent inaccuracy due to word sparseness. Experimental results demonstrate
that such a language modeling approach is competitive with current state-of-the-art database selection approaches. 相似文献
16.
基于P2P的适应性信息检索系统的设计 总被引:3,自引:1,他引:3
江淇 《现代图书情报技术》2005,21(9):41-44
针对现有搜索引擎的不足,提出了一个基于P2P的适应性信息检索系统设计方案,详细介绍了系统的各主要模块的功能和技术方法,进而分析了该模型的优势。 相似文献
17.
Cathy Oxley 《International Information and Library Review》2018,50(1):69-75
Libraries play a critical role in enhancing the learning landscape of the schools they support. In order for any library to become a powerhouse and a community meeting place, all library team members need to align with the library's vision, own it and begin to add their own strengths and talents purposefully. This article explores practical strategies for developing a visionary team, including supportive leadership, daily stand-up meetings, weekly staff meetings, special-focus teams, rostering and the “five conversations” approach. These effective strategies can be implemented across a broad range of library workforce contexts in order to ensure the most effective workforce teams are built. 相似文献
18.
Jiawei Huang Mahda M. Bagher Heather Dohn Ross Nathan Piekielek Jan Oliver Wallgrün Jiayan Zhao 《Journal of Map & Geography Libraries》2018,14(1):40-63
Libraries have been the key to preserving culture and historic legacy for centuries. One such treasure cataloged in The Pennsylvania State University (Penn State) Libraries is a collection of over 33,000 Sanborn? Fire Insurance Maps. Originally kept safe in metal drawers, the library has embarked on a journey to digitize this abundance of information, combine it with other media such as photographs, and make it accessible through a web interface. Inspired by these efforts, we accessed this information and took it to the next level. Using state of the art 3D modeling and immersive technologies, we created a historic 3D model and immersive experiences of Penn State, exemplarily for the 1922 campus. The resulting experiences can be accessed through the web but also through head mounted displays (HMDs) and mobile phones in combination with VR viewers such as the Google Cardboard. Additionally, they can be used anywhere in the world or on the campus itself as a way to enable remote and in situ experiences and learning. Immersive experiences let us connect to the past, the present and the future, and as such offer value to digital cultural heritage efforts. 相似文献
19.
开展扎实有效的人格养成教育的序列研究,是江阴市晨光实验小学从"八五"到"十二五"课题实施的轨迹。文章在简要解读课题的内涵,回顾近20年的研究历程,以及探寻课题研究价值的基础上,从生活指导、社团活动、课堂教学三个维度对操作实施进行了具体的阐释,旨在促进学生形成积极的人生态度,培养健康的审美情趣,养成自主的学习能力。 相似文献
20.
Television viewers construct many different meanings from the programs they watch. Here, we investigated whether ethnic prejudice is differentially influenced by the genre of television programs in their portrayal of ethnic minorities. We also wanted to determine whether a higher educational level reduces ethnic prejudice and television use. A self-reported questionnaire was administered to 401 Italian adults. Structural equation modeling was used to analyze the relationships between ethnic prejudice and television program contents and educational level. Viewing Reality and Variety Shows was positively related to ethnic prejudice, News and Public Affairs was negatively related, and Films and TV series had no apparent influence on prejudice. Educational level was negatively related to both ethnic prejudice and watching Reality and Variety Shows, and positively related to viewing News and Public Affairs and Films and TV series programs. 相似文献