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Digital Library Service Initiative of the Hong Kong Institute of Education Library
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作者 Lucia Tsui Sidney Cheng Ivan Chan 《上海交通大学学报》 EI CAS CSCD 北大核心 2003年第S1期95-100,共6页
This paper presented the philosophy and the design concepts of the Hong Kong Institute of Education (HKIEd) Library Digital Library Service Initiative, focusing on two in house developed digital library components, Ed... This paper presented the philosophy and the design concepts of the Hong Kong Institute of Education (HKIEd) Library Digital Library Service Initiative, focusing on two in house developed digital library components, EdIS and EdVideo, around its core digital library components of the INNOPAC Integrated Library System, Library Website, electronic resources from vendors. Description on the development of these systems was made. 展开更多
关键词 EdIs EdVideo INNOPAC DIGITAL LIBRARY PROJECTS
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Future China-Africa research collaboration in geoscience:Challenges and opportunities
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作者 Michael H.STEPHENSON Hassina MOURI +5 位作者 Gbenga OKUNLOLA CHENG Li WANG Meng ZHAO Yu GU Liping WANG Chengshan 《地学前缘》 北大核心 2025年第1期459-465,共7页
At the 19th G20 Summit in Brazil in November 2024,China promoted the development of sustainable solutions to climate change,biodiversity loss,and environmental pollution.This continued the theme of the 2016 G20 Hangzh... At the 19th G20 Summit in Brazil in November 2024,China promoted the development of sustainable solutions to climate change,biodiversity loss,and environmental pollution.This continued the theme of the 2016 G20 Hangzhou Summit,at which China placed development at the center of the G20’s macroeconomic policy coordination for the first time,adopting the G20 Action Plan on the United Nations 2030 Agenda for Sustainable Development and the G20 Initiative on Supporting Industrialization in Africa and Least Developed Countries.In Brazil,China announced actions on advancing modernization in Africa over the next three years with a Chinese commitment of RMB360 billion yuan in financial support.In this article,we examine the potential role of geoscience research and practice in development,particularly in the sustainable use of natural resources,the prevention of climate change impacts,as well as mitigation of geo-hazards and their health implications,indicating the areas where China’s geoscience for Africa is strong and where it requires more effort.We find that although China is the world’s leading publisher of scientific papers,its contribution to geoscience in Africa(the globe’s fastest-growing economic area),as shown by bibliometric research,appears to be rather small and inconsistent with the research priorities of Africa.Amongst the priorities for geoscience research in Africa,which are not addressed substantially by the research conducted so far,are sustainable mineral and hydrocarbon development,hydrology and hydrogeology,climate change and resilience,natural hazards,medical geology,agrominerals,and geoscience education and training.A particular opportunity for African nations is the presence of critical minerals-minerals needed for the energy transition and for batteries for electric cars in particular.Africa is well-endowed with many of these critical materials,such as rare earth elements and platinum group metals.Several research groups stress the need for the agency on the part of African institutions to map out these valuable resources,understand their value and the economics and sustainability of their extraction,encourage local business,attract investment,and scrutinize proposals from potential international investors to get the best deals.A strong point of existing China-led geoscience development includes the Deep-time Digital Earth(DDE)program online computing platform and its artificial intelligence tool GeoGPT,which is being developed in partnership with Zhejiang Laboratory.These are being developed with strong China funding support for free and wide global access,with a particular focus on Africa.These advanced tools will help to place the agency of development squarely in the hands of African scientists and institutions.In summary,the following are recommended:(1)a more coordinated and strategic approach to China-led geoscience research in Africa;(2)an Africa-centered,geoscience funding initiative that concentrates on relevant topics to the continent such as critical minerals exploration and other geological resources,materials and processes and their health implications on the populations and ecosystems in general,as well as climate change and climate change resilience;and(3)continued support for China-led international initiatives that seek to increase the agency and capacity of Africa geoscience researchers,for example the Deep-time Digital Earth platform. 展开更多
关键词 open science sustainable development digital empowerment China-Africa geo-collaboration Deep-Time Digital Earth
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一种结合有监督学习的动态主题模型 被引量:11
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作者 蒋卓人 陈燕 +2 位作者 高良才 汤帜 刘晓钟 《北京大学学报(自然科学版)》 EI CAS CSCD 北大核心 2015年第2期367-376,共10页
针对传统主题模型存在的不足,提出一种新的结合有监督学习的动态主题模型(Supervised Dynamic Topic Model,S-DTM)。该模型不仅能够随时间的变化对语言进行动态建模,而且结合有监督学习技术,在主题变分推理中加入标签约束,从而建立主题... 针对传统主题模型存在的不足,提出一种新的结合有监督学习的动态主题模型(Supervised Dynamic Topic Model,S-DTM)。该模型不仅能够随时间的变化对语言进行动态建模,而且结合有监督学习技术,在主题变分推理中加入标签约束,从而建立主题与标签之间的映射关系,提高主题的表达解释能力。通过在一个跨越25年"以自然语言处理领域的中文期刊论文为主导"的中文语料库上的实验,证明该模型相较于静态的有监督主题模型和无监督的动态主题模型,具有更好的语义解释概括能力,能更准确地反映文档的主题结构,更精确地捕捉主题–词汇概率分布的动态演化。 展开更多
关键词 有监督学习 动态主题模型 变分推理
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基于全文内容的学术论文研究方法自动分类研究 被引量:31
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作者 章成志 李卓 储荷婷 《情报学报》 CSSCI CSCD 北大核心 2020年第8期852-862,共11页
对学术论文所采用的研究方法进行自动分类,有助于研究方法使用行为的分析与研究方法的评估,进而为科研人员推荐或选择合适的研究方法提供依据。相比于摘要信息,全文内容包含更多关于研究方法的上下文信息,因此探索基于全文内容的学术论... 对学术论文所采用的研究方法进行自动分类,有助于研究方法使用行为的分析与研究方法的评估,进而为科研人员推荐或选择合适的研究方法提供依据。相比于摘要信息,全文内容包含更多关于研究方法的上下文信息,因此探索基于全文内容的学术论文研究方法自动分类具有重要的意义。本研究以图书情报领域的820篇学术论文全文为研究对象,邀请专家对其研究方法进行标注得到研究方法训练语料;采用多标签分类任务中问题转换法和算法自适应法,将朴素贝叶斯与支持向量机作为问题转换法的底层分类器,构建6种不同的分类模型,同时选用算法自适应法中的ML-KNN模型,分别对论文中使用的研究方法进行自动分类。实验结果表明,相较于学术论文的摘要信息,全文内容在研究方法分类的性能上有较大的提升;朴素贝叶斯算法在问题转换法的分类器链策略中表现最佳,F1值达到0.705;另外结果也表明不同的学术论文研究方法的特征表征能力不同,训练集的规模较少会导致分类的泛化效果差。 展开更多
关键词 研究方法分类 文本分类 全文内容 多标签分类
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全球网上中文人文社会科学期刊的现状与趋势 被引量:8
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作者 叶继元 Vickie Fu Doll 《大学图书馆学报》 CSSCI 北大核心 2001年第2期44-47,共4页
目前全球网络中文人文社会科学电子期刊已有数百种,涉及较多学科和门类,其发行方式、价格、可检内容多种多样。一些网上期刊代理发行机构和行业组织也已出现。但在上网数量、检索、精审制度、汉字编码、版权、服务方式等方面尚存在不... 目前全球网络中文人文社会科学电子期刊已有数百种,涉及较多学科和门类,其发行方式、价格、可检内容多种多样。一些网上期刊代理发行机构和行业组织也已出现。但在上网数量、检索、精审制度、汉字编码、版权、服务方式等方面尚存在不足。更多的印刷型期刊上网,更多的学术单位创办网上期刊,更好的编排、界面、链接,合理的权益和价格体系,采、编、发行、订购、检索、阅读、交流的新模式将是今后的发展趋势。 展开更多
关键词 世界 网络电子期刊 中文期刊 人文科学 社会科学 期刊质量 期刊代理发行机构 现状 发展趋势
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Characterization and technology of fast reducing roasting for fine iron materials 被引量:15
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作者 罗立群 黄红 余永富 《Journal of Central South University》 SCIE EI CAS 2012年第8期2272-2278,共7页
The features of the techniques of fast reducing roasting (FRR) and conventional magnetic roasting, as well as tremendous demands of iron ores in iron and steel industry of China, were briefly described. The test equ... The features of the techniques of fast reducing roasting (FRR) and conventional magnetic roasting, as well as tremendous demands of iron ores in iron and steel industry of China, were briefly described. The test equipment suitable for FRR of fine-grained materials was introduced. Weakly magnetic materials with grain size of 〈0.30 mm were converted into strongly magnetic materials by FRR for several to dozens of seconds. In a weakly reducing atmosphere and at 740-800 ~C, refractory powder iron material (〈0.30 mm) which is rich in specularite, limonite and Mg-Mn siderite was subjected to FRR for a few seconds to 60 s. Concentrate with iron grade of 55.67%-55.21%, high contents of Mg and Mn in the ore is obtained and the yield of magnetic separation reaches 81.66%-86.57%. The results of X-ray diffraction (XRD) analysis and magnetism detection of the material before and after FRR indicate that weakly magnetic material is mainly converted into strongly magnetic material Fe304 with specific saturation magnetic moment. The efficiency of FRR is consistent with TFe recovery of magnetic separation; meantime, the specific sa^u'ation magnetic moment increases from 33 to 42 times after FRR. Calculations show that speeds of flash magnetic roasting are obtained from several dozen to two or three hundred times, compared with rotary kiln or shaft furnace. This indicates that it is practicable to use the fast reducing roasting technique to improve the comprehensive utilization of iron ore resources. 展开更多
关键词 iron material reducing roasting thermal decomposition X-ray diffraction magnetic property
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Bibliometric analysis of UAV swarms 被引量:4
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作者 JIANG Yangyang GAO Yan +2 位作者 SONG Wenqi LI Yue QUAN Quan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2022年第2期406-425,共20页
Projects on unmanned aerial vehicle(UAV) swarms have been initiated in a big way in the last few years, especially from 2015 to 2016. As a result, the number of related works on UAV swarms has been on the rise, with t... Projects on unmanned aerial vehicle(UAV) swarms have been initiated in a big way in the last few years, especially from 2015 to 2016. As a result, the number of related works on UAV swarms has been on the rise, with the rate of growth dramatically accelerating since 2017. This research conducts a bibliometric analysis of robotics swarms and UAV swarms to answer the following questions:(i) Disciplines mentioned in the UAV swarms research.(ii) The future development trends and hotspots in the UAV swarms research.(iii) Tracking related outcomes in the UAV swarms research. 展开更多
关键词 unmanned aerial vehicle(UAV)swarm BIBLIOMETRIC mapping knowledge domain
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韩国的科学及其国际合作(1995-2000年) 被引量:2
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作者 Mee-Jean Kim +1 位作者 莫京(译) 任胜利(校) 《管理科学学报》 CSSCI 北大核心 2007年第A01期65-75,共11页
通过对期刊论文的分析,研究了韩国以国际合作方式的科技产出.此项研究涉及发表于1995-2000年间被SCI收录的44534篇论文,作者来自韩国的科研机构.为了方便对比,将研究分为1995-1997年和1998-2000年两个时段.结果表明,韩国的国际... 通过对期刊论文的分析,研究了韩国以国际合作方式的科技产出.此项研究涉及发表于1995-2000年间被SCI收录的44534篇论文,作者来自韩国的科研机构.为了方便对比,将研究分为1995-1997年和1998-2000年两个时段.结果表明,韩国的国际合作程度在第2阶段明显低于第1阶段.经济改革后,韩国的科研人员数量及研究和发展(R&D)总经费都有大幅度削减.当一些决定性因素,诸如科技规模、国家科技基础设施等增长时,科学上的国际合作程度却在降低.这种下降趋势很大程度上与不同学科领域被SCI收录的情况不同有关.在排名前10位的合作国家中,只有中国、加拿大与韩国的合作论文数有所上升. 展开更多
关键词 国际合作 韩国 科学 期刊论文 合作方式 科研机构 经济改革 定性因素
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Preparation,characterization and catalytic performance of Cu nanowire catalyst for CO_(2) hydrogenation 被引量:1
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作者 ZHANG Xiao-yan WANG Ming-hua +1 位作者 CHEN Zhong-yi ZHAI Yu-chun 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第4期691-700,共10页
Pure Cu nanowires as catalyst were prepared by electrochemical deposition and were used in CO2 hydrogenation to methanol.The active sites of the Cu based catalyst were discussed.The performance and structural developm... Pure Cu nanowires as catalyst were prepared by electrochemical deposition and were used in CO2 hydrogenation to methanol.The active sites of the Cu based catalyst were discussed.The performance and structural development of the catalyst were observed during CO2 hydrogenation.A mechanism for the deactivation of the catalyst was discussed.The key factors that affect the deactivation of the catalyst were found.Cu nanowire sample was characterized by SEM,EDS,XRD,and BET.The results show that Cu nanowires have very high sintering resistance and catalytic stability.This helps to develop high performance catalysts.The changes in the grain size,SEM morphology and catalytic properties of the sample during CO2 hydrogenation show that the migration of the Cu atoms on the surface of the Cu nanowires can occur.Continuous migration of Cu atoms and sintering of Cu grains can lead to flow blockage in gas channels.The gas channel flow blockage or the sintering of Cu grains can lead to deactivation of the catalyst.However,the shape of catalytic performance curve indicates that the main reason for the deactivation of the catalyst is the gas channel flow blockage. 展开更多
关键词 CO_(2) hydrogenation METHANOL Cu nanowire migration sintering flow blockage
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Scientometric and Webometric Methods 被引量:1
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作者 彼得.英格沃森 《图书情报知识》 CSSCI 北大核心 2010年第1期4-11,共8页
The paper presents two fundamental models of scientific communication and characterizes and exemplifies the concept of Scientometrics' and its sub-research areas: publication analysis, including so-called publicat... The paper presents two fundamental models of scientific communication and characterizes and exemplifies the concept of Scientometrics' and its sub-research areas: publication analysis, including so-called publication point evaluation; citation analysis; and crown indicators for research evaluation. The recent research area Webometrics' is briefly discussed. 展开更多
关键词 图书 情报 出版物 读者
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Humidity-Induced Spectral Shift in a Cross-DispersionEchelle Spectrometer and Its Theoretical Investigation 被引量:1
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作者 LIU Ke-ling HUANG Mao Hieftje Gary M 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2010年第9期2555-2559,共5页
The relationship between ambient relative humidity H and the position shift of a spectral line was investigated both experimentally and theoretically.An echelle-based ICP emission spectrometer equipped with a CID dete... The relationship between ambient relative humidity H and the position shift of a spectral line was investigated both experimentally and theoretically.An echelle-based ICP emission spectrometer equipped with a CID detector was used for experimental verification of the derived model.The shift of a spectral line is quantitatively described by two defined spectral shift functions: Δλx(x,λ,H)(in the x direction of the CID detector) and Δλy(y,λ,H)(in the y direction of the CID detector).Experimental results indicate that Δλx(x,λ,H) does not change with a variation in ambient relative humidity, but Δλy(y,λ,H) does.A spectral shift equation,i.e.an empirical second-order polynomial equation,can be used to describe the relationship between Δλy(y,λ,H) and H.Based on the classical dipole model,classical mechanics and electrodynamics the empirical spectral-shift equation involving Δλy(y,λ,H) and H was theoretically deduced.The theoretical result is in good agreement with the experimental findings.The theoretical results indicate that the coefficients of the empirical spectral-shift equation are related to the basic physical parameters of materials and the geometric configuration of the echelle CID ICP-AES,and also provide physical meaning to the coefficients of the empirical shift equation obtained experimentally. 展开更多
关键词 Emission spectrometry Position shift of a spectral line Spectral-shift equation
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一个争议性科研领域的文献计量学研究:聚合水领域1962—1974
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作者 EricAckermann 李小宁(译) 梁立明(校) 《管理科学学报》 CSSCI 北大核心 2007年第A01期1-12,共12页
本项研究关注不同类型的文献(书籍、期刊文章、会议论文集和技术报告),探讨了聚合水研究这个有争议的科研领域的文献计量学特征.文章以发表数量(P)计量发表状态或模式以及产出量,以篇(部)均被引率(CPP)计量影响力,还考察了... 本项研究关注不同类型的文献(书籍、期刊文章、会议论文集和技术报告),探讨了聚合水研究这个有争议的科研领域的文献计量学特征.文章以发表数量(P)计量发表状态或模式以及产出量,以篇(部)均被引率(CPP)计量影响力,还考察了作者自引频次(SC)和未被引发表物数量(UP)对P和CPP的影响.研究发现,该研究领域的发表模式类似于流行病传播模型,期刊文章的P值最高,书籍的CPP值最高,而SC和UP的影响并不重要.与几个非争议性科研领域文献的比较表明,我们的这些发现可能也是其他争议性研究领域文献共有的特征. 展开更多
关键词 文献计量学 科研 聚合 技术报告 传播模型 CPP 论文集
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A new discriminative sparse parameter classifier with iterative removal for face recognition
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作者 TANG De-yan ZHOU Si-wang +2 位作者 LUO Meng-ru CHEN Hao-wen TANG Hui 《Journal of Central South University》 SCIE EI CAS CSCD 2022年第4期1226-1238,共13页
Face recognition has been widely used and developed rapidly in recent years.The methods based on sparse representation have made great breakthroughs,and collaborative representation-based classification(CRC)is the typ... Face recognition has been widely used and developed rapidly in recent years.The methods based on sparse representation have made great breakthroughs,and collaborative representation-based classification(CRC)is the typical representative.However,CRC cannot distinguish similar samples well,leading to a wrong classification easily.As an improved method based on CRC,the two-phase test sample sparse representation(TPTSSR)removes the samples that make little contribution to the representation of the testing sample.Nevertheless,only one removal is not sufficient,since some useless samples may still be retained,along with some useful samples maybe being removed randomly.In this work,a novel classifier,called discriminative sparse parameter(DSP)classifier with iterative removal,is proposed for face recognition.The proposed DSP classifier utilizes sparse parameter to measure the representation ability of training samples straight-forward.Moreover,to avoid some useful samples being removed randomly with only one removal,DSP classifier removes most uncorrelated samples gradually with iterations.Extensive experiments on different typical poses,expressions and noisy face datasets are conducted to assess the performance of the proposed DSP classifier.The experimental results demonstrate that DSP classifier achieves a better recognition rate than the well-known SRC,CRC,RRC,RCR,SRMVS,RFSR and TPTSSR classifiers for face recognition in various situations. 展开更多
关键词 collaborative representation-based classification discriminative sparse parameter classifier face recognition iterative removal sparse representation two-phase test sample sparse representation
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RKP based secure tracking in wireless sensor networks
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作者 Wang Jiahao Qin Zhiguang +1 位作者 Geng Ji Wang Shengkun 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第1期175-183,共9页
To enhancing the wireless sensor network's security in target tracking and locating application, this article proposes a tracking cluster based mobile cluster distributed group rekeying protocol (MCDGR). Based on t... To enhancing the wireless sensor network's security in target tracking and locating application, this article proposes a tracking cluster based mobile cluster distributed group rekeying protocol (MCDGR). Based on the given sensitivity, sensors can locate the moving object in the monitored area and form a tracking cluster around it. This tracking cluster can follow the target logically, process data on the target and report to the sink node, and thus achieve the tracking function. We introduce a multi-path reinforcement scheme, q-composition scheme and one-way cryptographic hash function based random key predistribution algorithm (RKP), which can guarantee a high accuracy and security and a low energy consumption on the same time in large-scale sensor networks. 展开更多
关键词 sensor network MCDGR RKP SINK tracking cluster
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A dataset of scientific literature on floods,1990-2017
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作者 Zhang Hongyue Li Guoqing +2 位作者 Huang Mingrui Qing Xiuling Zhang Huarong 《中国科学数据(中英文网络版)》 CSCD 2018年第3期76-85,共10页
With an increasing number of scientific achievements published,it is particularly important to conduct literature-based knowledge discovery and data mining.Flood,as one of the most destructive natural disasters,has be... With an increasing number of scientific achievements published,it is particularly important to conduct literature-based knowledge discovery and data mining.Flood,as one of the most destructive natural disasters,has been the subject of numerous scientific publications.On January 1,2018,we conducted literature data collection and processing on flood research and categorized the retrieved paper records into Whole SCI Dataset(WS)and High-Citation SCI Dataset(HCS).These data sets can serve as basic data for bibliometric analysis to identify the status of global flood research during 1990-2017.Our study shows that while the Chinese Academy of Sciences was the most productive institution during this period,the United States was the most productive country.Besides,our keyword analysis reveals the potential popular issues and future trends of flood research. 展开更多
关键词 literature data sets FLOOD WS HCS
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