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121.
议信息时代图书馆员的角色转变及素质要求 总被引:10,自引:0,他引:10
指出信息时代图书馆员的角色定位由传统的图书馆员向具有时代特色的现代化信息馆员角色的转变,并重点阐述了信息馆员应具备的信息素质,以及提高信息素质的途径。 相似文献
122.
提出了旨在缩小信息鸿沟的电子政务中的智能Web信息服务模型。信息存取方式、信息理解能力和信息获取愿望的不同导致人们在决策时使用不同类型的信息。基于此,分析了当前我国电子政务网站服务提供现状,设计出一个由Web用户聚类层、Web信息利用分析层和个性化Web服务层三个层面构成的智能信息服务模型,并介绍了模型的主要特点和下一步的工作。 相似文献
123.
论文化发展视野下的图书馆功能 总被引:2,自引:0,他引:2
当今时代,文化在经济社会发展和综合国力竞争中的地位和作用日益凸显。文化发展的多样化、融合性、差异性、层次性等特征,必然带来图书馆功能的新变化。图书馆信息聚合与扩散功能的突显、教育引导功能的增强和社会服务功能的拓展,要求图书馆必须创新理念、机制、方式和文化。 相似文献
124.
Weijie Zhao 《国家科学评论(英文版)》2022,9(8)
‘We aim to have CO2 emissions peak before 2030 and achieve carbon neutrality before 2060,’ President Xi Jinping so declared at the General Debate of the 75th United Nations General Assembly on 22 September 2020. More than 130 countries globally have proposed their own carbon neutrality goals by 2050 or 2060. Thus, carbon neutrality is a collective effort of human societies to cope with the climate crisis. If all countries could follow their own plans and reach carbon neutrality in a few decades, we may have a chance to control global warming within 1.5 or 2oC, confining climate change to a relatively safe zone. As a developing country with a large population, high coal consumption and large manufacturing industries, can China achieve the huge task of societal transformation that will enable carbon peaking and carbon neutrality within the next four decades? How will China transform traditional power generation and manufacturing industries, as well as create new technologies for carbon capture and storage? In this panel discussion chaired by Prof. Xinhe Bao, a scientist of energy and chemistry, top experts gathered to discuss the challenges and potential solutions, outlining the coming ‘green industrial revolution’. Huiming Cheng Professor, Institute of Metal Research, Chinese Academy of Sciences; Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences Zhengtang Guo Professor, Institute of Geology and Geophysics, Chinese Academy of Sciences Yaling He Professor, School of Energy and Power Engineering, Xi’an Jiaotong University Zheng Li Professor, Institute of Climate Change and Sustainable Development, Tsinghua University Minggao Ouyang Professor, School of Vehicle and Mobility, Tsinghua University Zhengrong Shi Professor, College of Energy and Mechanical Engineering, Shanghai University of Electric Power Zaiku Xie Professor, China Petroleum and Chemical Corporation (SINOPEC) Xinhe Bao (Chair) Professor, University of Science and Technology of China, and Dalian Institute of Chemical Physics, Chinese Academy of Sciences Bao: Today we have experts from different disciplines related to energy to talk about the issues of carbon peaking and carbon neutrality in China. Since September 2020, China has initiated many plans and strategies for achieving these goals. I would like to invite Prof. Li to introduce the background and significance of achieving carbon neutrality in China. Li : There is now a global consensus on the crisis of climate change. It is a challenge for all human societies. Carbon peaking and carbon neutrality are the solutions targeting the source of climate change—the emission of greenhouse gases. Most countries have promised to achieve carbon neutrality, and from the European Green Deal to China''s initiatives, the goal is not just
From the European Green Deal to China''s initiatives, the goal is not just to reduce carbon emissions, but also to initiate a ‘green industrial revolution’.—Zheng Lito reduce carbon emissions, but also to initiate a ‘green industrial revolution’ and lead human society to a new path that does not depend upon fossil energies. Going green has become a global trend. If China wishes to achieve sustainable development in the future, the only wise choice is to follow, or even lead this trend. So, we can see that setting the carbon neutrality goal is a well-thought-out strategic decision of the Chinese government.Almost all countries aim to achieve carbon neutrality, but each country has its own energy structure and development stage, so the degree of difficulty in achieving these goals is different. In fact, western developed countries have already reached peak carbon emissions. Europe and the US reached their peak in the 1980s and 2005, thus have ∼70 and 45 years to achieve neutrality by 2050, respectively. But China is still developing and has not reached its peak. Moreover, our industrial structure is biased towards heavy industry and our energy structure is biased towards coal use, so it is a great challenge for China to reach its peak by 2030 and achieve neutrality by 2060.Furthermore, not all countries are equally responsible for the current climate crisis. Developing countries have not emitted as much carbon, historically, as developed countries, and they also have the right to develop. At the Glasgow Climate Change Conference in 2021, developed countries proposed setting 1.5°C, instead of 2°C, as the only limit for temperature rise, and proposed that all nations should ‘phase out’ the usage of coal. After negotiations and compromises, the final document kept the 2°C limit set by the 2015 Paris Agreement, and pointed out that we should keep 1.5°C within reach. It also replaced the term ‘phase out’ with ‘phase down’ regarding coal use.To summarize, to achieve carbon neutrality and to create a green society is a significant task for the entire world, benefiting all humanity. Bao: To achieve carbon neutrality, what can we learn from other countries? Li : There was a study of Net-Zero America in the US, which presented six different future scenarios under different energy structures and electrification levels. The study proposed several major strategies that we can learn from. First, the electrification of energy consumption end users is the most important approach for decreasing energy consumption and carbon emissions. Second, to achieve carbon neutrality, non-fossil energy will definitely need to become the primary energy source, but some fossil energy has to be maintained for the stability of the power grid. Thus, keeping a proper ratio of fossil and non-fossil sources is important. Third, carbon capture and storage (CCS) technologies must be simultaneously developed to neutralize the carbon emitted from fossil fuel usage. Actually, the CCS capacity is the decisive factor in determining the amount of fossil fuels we can use. Guo: Because of different social conditions, the challenges facing each country are also different. Many strategies cannot be simply transferred from other countries to China. I think there are three things we can learn from advanced countries. First, we can adopt advanced green technologies already implemented abroad. Second, we can learn how to build a low-carbon culture from European countries. In many European countries, almost everybody accepts the low-carbon concept, preferring to buy small-engined cars and saving energy and resources in their daily lives. That is what we can strive for. Third, in addition to the comprehensive national policies we have initiated, we should make customized plans of carbon neutrality for each province, each city and each town, in accordance with the unique regional conditions of natural resources, development level and energy structure. Cheng: When we talk about carbon neutrality, we mostly focus on energy and resource, but in Europe, people also consider industry, architecture, transportation, agriculture, ecology and many other sectors of society. I think this systematic approach is what we can learn from. Bao: China is also considering these various approaches. But as energy-related researchers, we may hear more about topics on energy. But you are right that carbon neutrality is a systems problem. Maybe we should first sort out the major topics we could talk about. He: I think there are three major aspects: first, emissions reduction in energy generation, namely, gradually replacing fossil fuels with natural gas and renewable energies; second, green transformation of energy consumption, such as the transformation of industries and transportation; third, development of CCS technologies. Moreover, both energy generation and energy consumption sectors are calling for breakthroughs in energy storage technologies. 相似文献
125.
Weijie Zhao 《国家科学评论(英文版)》2021,8(3):194-198
The COVID-19 pandemic has killed more than 1 000 000 people within nine months in 2020. The world is changed as the cities were locked down, the traffic reduced, and people forced to work from home and keep social distance. These controlling measures also resulted in drastic reduction of the emission of many air pollutants, providing researchers an unprecedented large-scale natural experiment in examining how the air quality would respond to a strong forcing. In this panel discussion held on 22 September 2020, five experts gathered to discuss their observations and analyses, as well as the current understanding and misconception about airborne transmission.This Forum article is dedicated to Prof. Martin Williams of the Imperial College London, who intended to join the panel discussion but passed away one day before it. Guy Brasseur Professor of Max Planck Institute for Meteorology, Germany Junji Cao Professor of Institute of Earth Environment, Chinese Academy of Sciences, China Aijun Ding Dean and Professor of School of Atmospheric Sciences, Nanjing University, China Lidia Morawska Professor of Queensland University of Technology, Australia Tong Zhu (Chair) Dean and Professor of College of Environmental Sciences and Engineering, Peking University, China 相似文献
126.
基于深度学习的中文专利自动分类方法研究 总被引:2,自引:0,他引:2
[目的/意义]面向当前国内专利审查和专利情报分析工作中对于海量专利分类的客观需求,设计了7种基于深度学习的专利自动分类方法,对比各种方法的分类效果,从而助力专利分类效率和效果的提升。[方法/过程]针对传统机器学习方法存在的缺陷,基于Word2Vec、CNN、RNN、Attention机制等深度学习技术,考虑专利文本语序特征、上下文特征以及分类关键特征,设计Word2Vec+TextCNN、Word2Vec+GRU、Word2Vec+BiGRU、Word2Vec+BiGRU+TextCNN等7种深度学习模型,以中国专利为例,选取IPC主分类号的"部"作为分类依据,对比这7种模型与3种传统分类模型在中文专利分类任务中的效果。[结果/结论]实证研究效果显示,采用考虑语序特征、上下文特征及强化关键特征的深度学习方法进行中文专利分类具有更优的分类效果。 相似文献
127.
[目的/意义]开放式创新背景下,平台企业所处的市场竞争越来越激烈,平台同质化严重,平台企业内部所拥有的创新资源、创新能力不足,无法有效支撑企业商业模式创新。跨界搜寻与大数据能力的协同作用能够为平台企业商业模式创新提供有力支撑。[方法/过程]对跨界搜寻、大数据能力及商业模式创新相关文献进行梳理,基于平台企业商业模式构成要素,构建跨界搜寻与大数据能力协同作用模型。[结果/结论]跨界搜寻有助于创新知识流动和创新资源获取,大数据能力可以完成资源整合及深度分析,二者的协同作用可以促进市场新知识发现,有利于平台企业商业模式创新。 相似文献
128.
基于地震反射波法超前预测系统的原理及主要技术手段,以栋梁坡隧道工程为实例,针对隧道复杂的地质条件,施工过程中将超前地质预报和地质素描调查相结合,先对隧道全段范围内地形、地层岩性等进行全面核查,然后结合核查结果运用地震反射波法预报掌子面前方的节理裂隙发育情况,围岩完整性等地质信息.开挖后验证情况与预测结果基本一致,为后续... 相似文献
129.
130.
赵勇军 《石家庄铁路职业技术学院学报》2007,6(1):69-72
结合马嘎车站站场改造实例,详细介绍站场改造的技术准备、施工方案、缩短封锁时间技巧、道岔整修,确保在封锁时间内完成施工任务,为今后站场改造施工组织提供借鉴。 相似文献