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91.
本文主要分析了气象科研机构情报室用户群的特点及需求,探讨了在网络信息技术条件下,为这些用户提供个性化服务的对策。 相似文献
92.
本文介绍了数字频率计设计的基本原理,对频率计所采用各种硬件除法进行了比较,提出了倍频计数法测量数字高频的实现方案,并给出了频率计设计的硬件电路原理和软件实现,结果表明这种方法实现了频率计的高速和高精度。 相似文献
93.
从现有城市规划数据的数据分类、数据代码、数据标准、数据报告入手,结合城市用地国家分类标准进行分析,提出一种包括专题规划信息分类、数据编码、数据分层的规划专题信息数据标准化技术。 相似文献
94.
在全球化时代,国际合作不仅成为大飞机研制生产的主要模式,同时也成为各国发展大飞机产业的战略选择。在我国国产大飞机项目实施过程中,要在坚持自主创新发展战略的同时,推动研发领域国际合作,通过在研发合作方式、合作内容、合作主体等方面的创新,加快技术追赶,并为我国大飞机领域的自主创新提供有效支撑。 相似文献
95.
Longitudinal trends in networks of university-industry-government relations in South Korea: The role of programmatic incentives 总被引:1,自引:0,他引:1
This study examines the longitudinal trend of systemness in networked research relations in South Korea using a triple helix (TH) indicator of university-industry-government (UIG) relations. The data were harvested from the Science Citation Index (SCI) and its counterparts in the social sciences (SSCI) and the arts and humanities (A&HCI). The total number of Korean SCI publications has grown rapidly since 1965. However, the TH indicator shows that the network dynamics have varied considerably according to the research policies of the national government. The collaboration patterns, as measured by co-authorship relations in the SCI noticeably increased, with some variation, from the mid-1970s to the mid-1990s. However, inter-institutional collaboration in the first decade of the 21st century was negatively influenced by the new national science and technology (S&T) research policies that evaluated domestic scientists and research groups based on their international publication numbers rather than on the level of cooperation among academic, private, and public domains. The results reveal that Korea has failed to boost its national research capacity by neglecting the network effects in science, technology, and industry. 相似文献
96.
97.
Fangzhou Liu Xiang Li Muhua Zhao Mengjian Guo Kehong Han Xinxin Dong Jing Zhao Wanlun Cai Qifa Zhang Hongxia Hua 《国家科学评论(英文版)》2020,7(7):1181
Rice planthoppers, the most devastating rice pests, occur in two wing forms: the short-wing form for rapid population growth and long-wing form for long-distance migration, which together create the mechanism for outbreak. Here we show that Ultrabithorax (Ubx) is a key regulator for switching between the long- and short-wing forms of rice planthoppers. Ubx is expressed in both forewing and hindwing pads, which is different from the canonical model of Ubx expression. In brown planthoppers, expression of Ubx (NlUbx) is regulated by nutritional status of the rice host. High-quality young plants induce NlUbx expression leading to the short-wing form; low-quality ripe plants reduce NlUbx expression resulting in long-wing form. We also showed that NlUbx is regulated by the insulin receptors NlInR1 and NlInR2. The default expression of NlInR1 inhibits NlUbx resulting in long-wings, while high-quality hosts induce NlInR2 expression, which represses NlInR1 thus promoting NlUbx expression to produce short-wings. 相似文献
98.
Xier Luo Yu Zhou Bing Zhang Yi Zhang Xiaobo Wang Tong Feng Zhipeng Li Kuiqing Cui Zhiqiang Wang Chan Luo Hui Li Yanfei Deng Fenghua Lu Jianlin Han Yongwang Miao Huaming Mao Xiaoyan Yi Cheng Ai Shigang Wu Alun Li Zhichao Wu Zijun Zhuo Do Da Giang Bikash Mitra Mohammad Farhad Vahidi Shahid Mansoor Sahar Ahmed Al-Bayatti Eka Meutia Sari Neena Amatya Gorkhali Sigit Prastowo Laiba Shafique Guoyou Ye Qian Qian Baoshan Chen Deshun Shi Jue Ruan Qingyou Liu 《国家科学评论(英文版)》2020,7(3):686
Domesticated buffaloes have been integral to rice-paddy agro-ecosystems for millennia, yet relatively little is known about the buffalo genomics. Here, we sequenced and assembled reference genomes for both swamp and river buffaloes and we re-sequenced 230 individuals (132 swamp buffaloes and 98 river buffaloes) sampled from across Asia and Europe. Beyond the many actionable insights that our study revealed about the domestication, basic physiology and breeding of buffalo, we made the striking discovery that the divergent domestication traits between swamp and river buffaloes can be explained with recent selections of genes on social behavior, digestion metabolism, strengths and milk production. 相似文献
99.
当前经济环境中,供应链企业间进行协同创新对于提升企业竞争力乃至整个供应链的市场竞争力都具有十分重要的意义;而供应链企业进行充分的知识共享是其进行有效的协同创新的必要条件。本文首先对供应链企业间协同创新及其知识共享相关文献进行系统的梳理及理论分析,在此基础上构建供应链企业间基于知识共享的协同创新模型,模型分析表明当知识共享风险过大时,企业间的协同创新行为难以发生;当知识共享风险较小时,企业才酌情考虑协同创新相关事宜。最后,本文主要就如何规避知识共享中的风险进而促进供应链企业间的协同创新提出了有针对性的建议。 相似文献
100.
Finite-time synchronization of drive-response systems via periodically intermittent adaptive control
Jun Mei Minghui Jiang Xiaohong Wang Jiali Han Shuangtao Wang 《Journal of The Franklin Institute》2014
In this paper, the finite-time synchronization between two complex dynamical networks via the periodically intermittent adaptive control and the periodically intermittent feedback control is studied. The finite-time synchronization criteria are derived based on finite-time stability theory, the differential inequality and the analysis technique. Since the traditional synchronization criteria for some models are improved in the convergence time by using the novel periodically intermittent adaptive control and periodically intermittent feedback control, the results of this paper are important. Numerical examples are finally presented to illustrate the effectiveness and correctness of the theoretical results. 相似文献