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Some New Transition Classes in the Fractional Quantum Hall Effect and Their Critical Filling Factors

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Chinese Physics Letters 1996年第3期13卷 215-218页

作者： CHEN Ying-jian institute of scientific and technical information of china Beijing 100038

The transitions between fractional quantum Hall states are classified into three equivalence classes by virtue of the matrix *** is pointed out that there probably exist two new transition classes and the critical fil... 详细信息

关键词： theory. transitions Transition

Research on technology cluster evolution of global MEMS sensors based on patent co-occurrence analysis

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High Technology Letters 2019年第2期25卷 197-206页

作者： Liang Qinqin institute of scientific and technical information of china

At present, microelectro mechanical systems (MEMS) sensors have gradually replaced traditional mechanical sensors and are applied to several fields. Many developed countries pay high attention to technological innovation of MEMS sensors, and have applied a large number of patents since 2000. In this study, the patents of MEMS sensor from 2000 to 2015 are researched, the patents data is collected from Derwent Innovation Index (DII), and the method of co-classification analysis is used to investigate the technology cluster evolution of MEMS sensors. Results show that the technology diffusion occurrs in each technical field and the technology relevance between different technical fields is changed over time. On the whole, the evolution process of MEMS sensor is the manufacture and material of sensor chip, the electronic components and measuring function, the computing and control technology, and applications to biochemical field and communication.

关键词： co-classification analysis technology cluster microelectro mechanical system(MEMS) patent analysis

Studies of layout of world machine tools industry based on patent analysis

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High Technology Letters 2013年第3期19卷 246-253页

作者：张涛 Zhang Xu Li Zhirong Zhao Yunhua Zhou Lijuan institute of scientific and technical information of china

As the foundation of an industrialized country nowadays,machine tools industry is regarded as the engine of industrial development of a *** developed countries,such as USA,Germany and Japan,have widely deployed the technology of using the patent in order to keep their strength in various *** research examins the CNC machine tools industry in the world by using the patent analysis *** first gives an overview about the world patent application in CNC machine tools industry from 1963 to 2010 and divides the development of the industry into five *** also lists the patent application of the world top 20 countries,where the top 5 countries are *** patents of the world top 10 companies of machine tools manufacturers are mapped according to the international patent classification(IPC),and the future trends of world machine tools industry are *** conclusions and suggestions are presented.

关键词： machine tools industry computerized numerical control (CNC) machine tools patent analysis international patent classification (IPC) development trends

Scientometric analysis of physics (1979-2008):A quantitative description of scientific impact

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Science china(Physics,Mechanics & Astronomy) 2011年第1期54卷 176-182页

作者： ZHENG YanNing YUAN JunPeng PAN YunTao ZHAO XiaoYuan institute of scientific and technical of information of china Beijing 100038 China

Citations are a way to show how researchers build on existing research to further evolve *** citation count is an indication of the influence of specific *** importance of citations means that it is valuable to analyze the articles that are cited the *** research investigates highly-cited articles in physics (1979-2008) using citation data from the ISI Web of *** this study,1544205 articles were *** objective of the analysis was to identify and list the highly-productive countries,institutions,authors,and fields in *** on the analysis,it was found that the USA is the world leader in physics,and Japan has maintained the highest growth rate in physics research since ***,the research focus at Bell Labs and IBM has played important roles in physics.A striking fact is that the five most active authors are all Japanese,but the five most active institutions are all in the *** fact,only The University of Tokyo is ranked among the top 11 institutions,and only American authors have single-author articles ranked among the top 19 *** highest-impact articles are distributed across 25 subjects ***,Multidisciplinary has 424 articles,and is ranked at No.1 in total articles;followed by Physics,Condensed *** study can provide science policy makers with a picture of innovation capability in this field and help them make better ***,this study will stimulate useful discussion among scientists and research managers about future research directions.

关键词： high-impact articles domestic articles international articles social network analysis Web of Science

Effective search with saliency-based matching and cluster-based browsing

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High Technology Letters 2013年第1期19卷 105-109页

作者：张晓宇 institute of scientific and technical information of china

Similarity matching and this paper, a saliency-based information presentation are two matching algorithm is proposed key factors in information retrieval. In for user-oriented search based on the psychological studies on human perception, and major emphasis on the saliently similar aspect of objects to be compared is placed and thus the search result is more agreeable for users. After relevant results are obtained, the cluster-based browsing algorithm is adopted for search result presentation based on social network analysis. By organizing the results in clustered lists, the user can have a general understanding of the whole collection by viewing only a small part of results and locate those of major interest rapidly. Experimental results demonstrate the advantages of the proposed algorithm over the traditional work.

关键词： information retrieval saliency-based matching human perception cluster-based browsing social network

Assessing china 2030 carbon emissions from fossil fuels:based on system dynamics model

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High Technology Letters 2015年第2期21卷 178-184页

作者：佟贺丰 Qu Weishuang institute of scientific and technical information of china Millennium institute

The Chinese government has set ambitious targets to reduce the per unit of GDP by 40% ~45% during 2005 to 2020 and achieve the intensity peaking of carbon emissions of CO2 emissions a- round 2030. The T21 national development model for china was developed for the purpose of analy- zing the effects of long-term national policies that relate to carbon emissions, loss of farm land, water shortage, energy security, food security, and their contributions to this reduction target. The focus of this paper is on the policies that have substantial impacts on carbon emissions from fossil fuels. Four scenarios are developed with the model to simulate future carbon emissions ： 1 ） the BAU （ busi- ness as usual） scenario, showing the likely results of continuing current policies; 2 ） the TECH （technology） scenario showing the effects of more investment in renewable energy sources and promoting more energy efficient technologies; 3 ） the BEHAVIOR scenario, showing how government tax and price policies, together with public education programs, would instigate behaviour changes towards more sustainable living; and 4 ） the TECH＆BEHA scenario, which shows the results of combining scenarios 2 and 3. The simulation results show that CO2 emissions reduction targets of china are achievable, but also require great effort to put in.

关键词： system dynamics model carbon emissions GDP carbon intensity system simulation

A New Algorithm for Literature Recommendation Based on a Bibliographic Heterogeneous information Network

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Chinese Journal of Electronics 2018年第4期27卷 761-767页

作者： LI Linna WANG Lijun JIANG Xueqin HAN Hongqi ZHAI Yun institute of scientific and technical information of china E-Government Research Center Chinese Academy of Governance

A literature recommendation algorithm based on a heterogeneous information network is proposed. The proposed algorithm can process different types of semantic information and implicit feedback. The experimental results show that the proposed algorithm can provide more effective recommendations than those algorithms without employing these semantic information and implicit feedback.

关键词： Literature recommendation algorithm Heterogeneous information network Meta-path Classification Bayesian ranking

A new item-based deep network structure using a restricted Boltzmann machine for collaborative filtering

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Frontiers of information Technology & Electronic Engineering 2017年第5期18卷 658-666页

作者： Yong-ping DU Chang-qing YAO Shu-hua HUO Jing-xuan LIU institute of Computer Science Beijing University of TechnologyBeijing 100124China institute of scientific and technical information of china Beijing 100038China

The collaborative filtering(CF) technique has been widely used recently in recommendation systems. It needs historical data to give predictions. However, the data sparsity problem still exists. We propose a new item-based restricted Boltzmann machine(RBM) approach for CF and use the deep multilayer RBM network structure, which alleviates the data sparsity problem and has excellent ability to extract features. Each item is treated as a single RBM, and different items share the same weights and biases. The parameters are learned layer by layer in the deep network. The batch gradient descent algorithm with minibatch is used to increase the convergence speed. The new feature vector discovered by the multilayer RBM network structure is very effective in predicting a rating and achieves a better result. Experimental results on the data set of MovieL ens show that the item-based multilayer RBM approach achieves the best performance, with a mean absolute error of 0.6424 and a root-mean-square error of 0.7843.

关键词： Restricted Boltzmann machine Deep network structure Collaborative filtering Recommendation system

Identifying multidisciplinary problems from scientific publications based on a text generation method

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Journal of Data and information Science 2024年第3期9卷 213-237页

作者： Ziyan Xu Hongqi Han Linna Li Junsheng Zhang Zexu Zhou institute of scientific and technical information of china Beijing 100038China

Purpose:A text generation based multidisciplinary problem identification method is proposed,which does not rely on a large amount of data ***/methodology/approach:The proposed method first identifies the research objective types and disciplinary labels of papers using a text classification technique;second,it generates abstractive titles for each paper based on abstract and research objective types using a generative pre-trained language model;third,it extracts problem phrases from generated titles according to regular expression rules;fourth,it creates problem relation networks and identifies the same problems by exploiting a weighted community detection algorithm;finally,it identifies multidisciplinary problems based on the disciplinary labels of ***:Experiments in the“Carbon Peaking and Carbon Neutrality”field show that the proposed method can effectively identify multidisciplinary research *** disciplinary distribution of the identified problems is consistent with our understanding of multidisciplinary collaboration in the *** limitations:It is necessary to use the proposed method in other multidisciplinary fields to validate its *** implications:Multidisciplinary problem identification helps to gather multidisciplinary forces to solve complex real-world problems for the governments,fund valuable multidisciplinary problems for research management authorities,and borrow ideas from other disciplines for ***/value:This approach proposes a novel multidisciplinary problem identification method based on text generation,which identifies multidisciplinary problems based on generative abstractive titles of papers without data annotation required by standard sequence labeling techniques.

关键词： Problem identification Multidisciplinary Text generation Text classification