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1.
L. Leydesdorff 《Scientometrics》1987,11(5-6):295-324
The dynamic mapping of science using the data in theScience Citation Index was put on the research agenda of science studies byDe Solla Price in the mid 1960s. Recently, proponents of ‘co-citation cluster analysis’ have claimed that in principle their methodology makes such mapping possible. The study examines this claim, both methodologically and theoretically, in relation to other means of mapping science. A detailed study of a co-citation map, its core documents' citation patterns and the related journal structures, is presented. At these three levels of possible study of aggregates of citations, an analysis is pursued for the years 1978 to 1984. The many different statistical methods which are in use for the analysis of the respective datamatrices—such as cluster analysis, factor analysis and multidimensional scalling—are assessed with a view to their potential to contribute to a better undérstanding of the dynamics at the different levels in relation to each other. This will lead to some recommendations about methods to use and to avoid when we aim at a comprehensive mapping of science. Although the study is pursued at a formal and analytical level, in the conclusions an attempt is made to reflect on the results in terms of further substantial questions for the study of the dynamics of science.  相似文献   

2.
This paper gives an outline of a new bibliometric database based upon all articles published by authors from the Netherlands, and processed during the time period 1980–1993 by the Institute for Scientific Information (ISI) for theScience Citation Index (SCI),Social Science Citation Index (SSCI) andArts & Humanities Citation Index (A&HCI). The paper describes various types of information added to the database: data on articles citing the Dutch publications; detailed citation data on ISI journals and subfields; and a classification system of publishing main organizations, appearing in the addresses. Moreover, an overview is given of the types of bibliometric indicators that were constructed. Their relationship to indicators developed by other researchers in the field is discussed. Finally, two applications are given in order to illustrate the potentials of the database and of the bibliometric indicators derived from it. The first represents a synthesis of ‘classical’ macro indicator studies at the one hand, and bibliometric analyses of research groups or institutes at the other. The second application gives for the first time a detailed analysis of a country's publication output per institutional sector.  相似文献   

3.
Cuban scientific output at macro level has not been frequently studied in the literature on scientometrics. The current paper explores the different metric approaches to the Cuban scientific activity carried out by national and international authors. Also, the article develops a scientometric study of the Cuban scientific production as included in Scopus during the period 1996–2007, using socio-economic indicators combined with bibliometric indicators supported by the SCImago Journal & Country Rank. Web of Science and Scopus are compared as information sources. Results confirm the possibility to use Scopus to obtain an objective picture of the Cuban science behaviour during the end of the 1990s and the beginning of the XXI century. The SCImago Journal & Country Rank, in this case, offers an important set of indicators. The combination of these indicators with those related to socio-economic aspects of activities in Science and Technology, allow the authors to show a perspective of the Cuban science system evolution during the period analyzed. The inclusion in Scopus of less-cited journals published in Spanish language and its impact on productivity and citation-based indicators is also discussed. Our investigation found an increasing growth of the Cuban scientific production during the whole period, which is in correspondence to the country efforts and expenditures in Research and Development activities.  相似文献   

4.
Jiang Wu 《Scientometrics》2013,94(1):181-201
This paper proposes a citation rank based on spatial diversity (SDCR) in terms of cities and countries, focusing on the measurement of the “spatial” aspect in citation networks. Our main goal is to solve the citation bias caused by different geographical locations of citations. We empirically investigate spatial properties of citing distances, citation patterns and spatial diversity to understand geographical knowledge diffusion, based on the data from “Transportation Science and Technology” subject category in the Web of Science (1966–2009). We also compare the proposed ranking method with other bibliometric measures, and conduct a case study to figure out the recent ranks of the well-established authors in Transportation research. It is found that the SDCR of a focal author is highly correlated with the sum of spatial diversity weights (“strength”) of all his in-links, and it is better to set the damping factors smaller than 0.75 when ranking authors with various initial academic years by SDCR. The cases show that Hong Kong is becoming a cluster in Transportation research.  相似文献   

5.
Numerous studies have sought to uncover violations of objectivity and impartiality in peer review; however the notion of reciprocity has been absent in much of this discussion, particularly as it relates to gendered and ethnicized behaviors of peer review. The current study addresses this gap in research by investigating patterns of reciprocity (i.e., correspondences between patterns of recommendations received by authors and patterns of recommendations given by reviewers in the same social group) by perceived gender and ethnicity of reviewers and authors for submissions to the Journal of the American Society for Information Science and Technology from June 2009 to May 2011. The degree of reciprocity for each social group was examined by employing Monte Carlo resampling to extrapolate more robust patterns from the limited data available. We found that papers with female authors received more negative reviews than reviews for male authors. Reciprocity was suggested by the fact that female reviewers gave lower reviews than male reviewers. Reciprocity was also exhibited by ethnicity, although non-Western reviewers gave disproportionately more recommendations of major revision, while non-Western authors tended to receive more outright rejections. This study provides a novel theoretical and methodological basis for future studies on reciprocity in peer review.  相似文献   

6.
Uncovering the temporal trend in crash counts provides a good understanding of the context for pedestrian safety. With a rareness of pedestrian crashes it is impossible to investigate monthly temporal effects with an individual segment/intersection level data, thus the time dependence should be derived from the aggregated level data. Most previous studies have used annual data to investigate the differences in pedestrian crashes between different regions or countries in a given year, and/or to look at time trends of fatal pedestrian injuries annually. Use of annual data unfortunately does not provide sufficient information on patterns in time trends or seasonal effects. This paper describes statistical methods uncovering patterns in monthly pedestrian crashes aggregated on urban roads in Connecticut from January 1995 to December 2009. We investigate the temporal behavior of injury severity levels, including fatal (K), severe injury (A), evident minor injury (B), and non-evident possible injury and property damage only (C and O), as proportions of all pedestrian crashes in each month, taking into consideration effects of time trend, seasonal variations and VMT (vehicle miles traveled). This type of dependent multivariate data is characterized by positive components which sum to one, and occurs in several applications in science and engineering. We describe a dynamic framework with vector autoregressions (VAR) for modeling and predicting compositional time series. Combining these predictions with predictions from a univariate statistical model for total crash counts will then enable us to predict pedestrian crash counts with the different injury severity levels. We compare these predictions with those obtained from fitting separate univariate models to time series of crash counts at each injury severity level. We also show that the dynamic models perform better than the corresponding static models. We implement the Integrated Nested Laplace Approximation (INLA) approach to enable fast Bayesian posterior computation.  相似文献   

7.
A bibliometric analysis was conducted to evaluate the global scientific output of proteomics research in the Science Citation Index Expanded from 1995 to 2010. The document types, languages, journals, categories, countries, and institutions were analyzed to obtain publication patterns. Research focuses and trends were revealed by a word cluster method related to author keywords, title, abstract, and KeyWords Plus. Bradford’s Law and the correlation between keywords and institutions were identified to look deeper into the nature works. Proteomics and Journal of Proteome Research published the most articles in proteomics research. The researchers focused on the categories of biochemical research methods, and biochemistry and molecular biology. The USA and Harvard University were the most productive country and institution, respectively, while China was the fastest-growing country due to the support by Chinese government. The distribution of author keywords provided the important clues of hot issues. Results showed that mass spectrometry and two-dimensional gel electrophoresis had been the most frequently used research methods in the past 16 years; and cancer proteomics had a strong potential in the near future. Furthermore, biologists contributed significantly to proteomics research, and were more likely to co-operate with medical scientists.  相似文献   

8.
We study central-place foraging patterns of Aphaenogaster senilis ants at a population level by video framing individual ant trajectories in a circular arena with a nest connected to its centre. The ants naturally leave and enter the nest and forage generating non-trivial movement patterns around the nest. Our data analysis indicated that the trajectories observed can be classified into two strategies: the risk-averse strategy, which involves wandering around the nest without departing far from it and the risk-prone strategy, which involves long exploration paths with periodic returns to the central region, nearby the nest. We found that both risk-prone and risk-averse strategies exhibit qualitatively the same reorientation patterns, with the time between consecutive reorientations covering a wide range of scales, and fitting a stretched exponential function. Nevertheless, differences in the temporal scales and the time variability of such reorientation events differ, together with other aspects of motion, such as average speed and turns. Our results give experimental evidence that the internal mechanisms driving reorientations in ants tend to favour frequently long relocations, as theory predicts for efficient exploration in patchy landscapes, but ants engaged in central-place foraging can modulate such behaviour to control distances from the nest. Previous works on the species support the idea that risk-prone and risk-averse strategies may reflect actual differences between individuals age and experience; these factors (age and experience) should be then relevant in modulating the internal reorientation clocks. To support the validity of our findings, we develop a random-walk model combining stretched exponential reorientation clocks with klinokinesis that fits the time length and the travelled distance distributions of the observed trajectories.  相似文献   

9.
This paper reports first results on the interplay of different levels of the science system. Specifically, we would like to understand if and how collaborations at the author (micro) level impact collaboration patterns among institutions (meso) and countries (macro). All 2,541 papers (articles, proceedings papers, and reviews) published in the international journal Scientometrics from 1978–2010 are analyzed and visualized across the different levels and the evolving collaboration networks are animated over time. Studying the three levels in isolation we gain a number of insights: (1) USA, Belgium, and England dominated the publications in Scientometrics throughout the 33-year period, while the Netherlands and Spain were the subdominant countries; (2) the number of institutions and authors increased over time, yet the average number of papers per institution grew slowly and the average number of papers per author decreased in recent years; (3) a few key institutions, including Univ Sussex, KHBO, Katholieke Univ Leuven, Hungarian Acad Sci, and Leiden Univ, have a high centrality and betweenness, acting as gatekeepers in the collaboration network; (4) early key authors (Lancaster FW, Braun T, Courtial JP, Narin F, or VanRaan AFJ) have been replaced by current prolific authors (such as Rousseau R or Moed HF). Comparing results across the three levels reveals that results from one level might propagate to the next level, e.g., top rankings of a few key single authors can not only have a major impact on the ranking of their institution but also lead to a dominance of their country at the country level; movement of prolific authors among institutions can lead to major structural changes in the institution networks. To our knowledge, this is the most comprehensive and the only multi-level study of Scientometrics conducted to date.  相似文献   

10.
Designing is a knowledge-intensive activity. For novice design engineers, an important means of acquiring knowledge is to consult experienced colleagues. We observed novice?Cexpert consultations as part of three engineering projects in a large aerospace company. Seven meetings were analysed in detail regarding the design activity, the content, and the form of interaction. Although the meetings were initiated for the purpose of information seeking, this process amounted to only 8% of the time compared to knowledge creation between novices and experts (47% of meeting time), and contextual information sharing (45% of meeting time). Both experts and novices were found to contribute equally and interactively to the discussion and analysis of solutions. The analysis showed how the processes alternated in the meetings. We identified tentative patterns on how these consultation processes change over the course of the design process phases. The micro-level analysis of the design activities and form of interaction provided a deeper understanding of how the consultation processes are discursively produced by the experts and novices. Finally, implications for design engineering practitioners are derived and suggestions for further research are provided.  相似文献   

11.
A detailed analysis of the research carried out in Mexico in the physics specialty of particles and fields (MPPF) reveals the way the current production and citation patterns evolved over a period of 60 years. The basis for the analysis were the publications and citations registered in the Stanford Public Information REtrieval SystemHigh Energy Physics (SPIRES) from 1970 to 2007. The historical coverage afforded by the Science Citation Index provided supplementary data from 1948 to 1979. Papers were classified into five research types: theoretical, phenomenological, experimental, cosmological, and other, while citations were identified as coming from: published or unpublished sources. Results show that the development of MPPF emerged from traditional theoretical and phenomenological research and that the most notable changes taking place in production and impact are associated with the community’s involvement in more productive and more internationally visible research practices, characteristic of large international collaborations, leaders in experimental physics and in the authorship of review papers.  相似文献   

12.
Feiler, D., Nagel, M., Stottmeister, E., Hermenau, H., Hendel, P. and Dobberkau, H.-J., 1988. Interpretation of complex capillary chromatograms by means of structural pattern recognition algorithms using fuzzy theory. Chemometrics and Intelligent Laboratory Systems, 4: 231-237.The comparison of complex chromatographic patterns is a frequent task in analytical work, especially in the area of environmental analysis. The combination of capillary gas chromatography/automated pattern recognition can be considered to be an intelligent laboratory system that provides answers to a given analytical problem.A modern and effective approach in this field is the use of structural pattern recognition algorithms based on fuzzy theory.The application of library search algorithms for comparison of unknown sample patterns with reference patterns stored in a chromatogram library is described. The interpretation of the results for identification tasks is achieved by taking the expert knowledge of the analyst into account. A new aspect, presented here, is the illustration of the similarity measures using elements of the exploratory data analysis.  相似文献   

13.
The purpose of this paper is to highlight the weakness of innovative activities and guide the improvement of innovation efficiency at country-level through carefully comparing innovation efficiency across countries. Following the conceptual framework which divides innovation processes into knowledge production process (KPP) and knowledge commercialization process (KCP) and applying dual network-DEA models, this paper tries to take economic benefit of R&D outputs into account. Moreover, we construct the production frontier of the innovation processes and two component processes under different assumptions (e.g., constant returns-to-scale, variable returns-to-scale and non-increasing returns-to-scale) for 35 countries over the period 2007–2011. Based on the production frontier, we do not only estimate technical efficiency and scale efficiency for each country but also investigate and verify whether returns-to-scale of each country are decreasing or increasing. Furthermore, we add together the radial movement and the slack movement to acquire input redundancy. We decompose the input redundancy into two parts: redundancy caused by technical inefficiency (R_TI) and redundancy caused by scale inefficiency (R_SI), and carry out a detail analysis of the input redundancy. We find specific circumstances of inefficiency and redundancy vary with the different countries’ characteristics and development stages. Moreover, innovation efficiency statistically mainly depends on the KCP efficiency. In particular, the study reveals that China suffers scale inefficiency is attributed to insufficient macro-level coordination, malfunctioning funding system, and flawed evaluations and incentives. Finally, public policy implications are proposed for the inefficient countries.  相似文献   

14.
In this paper attempt has been made to unfold the intellectual base in ocean science and technology. The articles appeared in Science Citation Index (SCI) under Oceanography in the year 2000 were analyzed to decipher the scientist to scientist , organization to organization and country to country network structures. The causal linkages between the knowledge productivity function and the socio-economic imperatives of knowledge production units were studied.  相似文献   

15.
This study was designed to evaluate China’s scientific output of chemical engineering in Science Citation Index Expanded in the Web of Science from 1992 to 2011. The document type, language, trend and collaboration patterns were analyzed, as well as the output of different journals. Distributions of article titles and abstracts, author keywords, KeyWords Plus of different periods, and the most cited articles were studied to figure out the research focuses and trends. Chinese Journal of Catalysis, Industrial & Engineering Chemistry Research, and Chinese Journal of Chemical Engineering published most of Chinese articles in the area of chemical engineering. The Chemical Engineering Department of Tsinghua University, Zhejiang University, Tianjin University, and East China University of Science and Technology were the top four institutions that published most articles in China. This study showed that adsorption, photocatalysis and synthesis have been the hot points of research in the past two decades, while ionic liquid tends to be the new area of special interest in future. Pseudo-second order model for sorption processes is getting more and more popular with great influence since its publication. In addition, the ratio of institutional independent articles: nationally collaborative articles: internationally collaborative articles has been developed to compare different institutions’ publication characteristics.  相似文献   

16.
In this paper, we study the spatial characteristics of a sample of 2605 highly productive economists, and a subsample of 332 economists with outstanding productivity. Individual productivity is measured in terms of a quality index that weights the number of publications up to 2007 in four journal classes. We analyze the following four issues. (1) The “funneling effect” towards the US and the clustering of scholars in the top US institutions. (2) The high degree of collective inbreeding in the training of elite members. (3) The partition of those born in a given country into brain drain (who work in a country different from their country of origin), brain circulation (who study and/or work abroad followed by a return to the home country), and stayers (whose entire academic career takes place in their country of origin). We also study the partition of the economists working in 2007 in a given geographical area into nationals (stayers plus brain circulation) and migrants (brain drained from other countries). (4) Finally, we estimate the research output in different geographical areas in two instances: when we classify researchers by the institution where they work in 2007, or by their country of origin.  相似文献   

17.
Glänzel  Wolfgang  Schlemmer  Balázs  Thijs  Bart 《Scientometrics》2003,58(3):571-586
According to Garfield (1980),most scientists can name an example of an important discovery that had little initial impact on contemporary research. And he uses Mendel's work a classical example. Delayed recognition is sometimes used by scientists as an argument against citation-based indicators based on citation windows defined for a short- or medium-term initial period beginning with the paper's publication year. This study is focussed on a large-scale analysis of the citation history of all papers indexed in the 1980 annual volume of the Science Citation Index. The objective is two-fold, particularly, to analyse whether the share of delayed recognition papers is significant and whether such papers are typical of the work of their authors at that time. In a first step, the background of advanced bibliometric models by Glänzel, Egghe, Rousseau and Burrell of stochastic citation processes and first-citation distributions is described briefly. The second part is devoted to the bibliometric analysis of first-citation statistics and of the phenomenon of citation delay. In a third step, finally, delayed reception publications have been studied individually. Their topics and the citation patterns of other papers by the same authors have been studied to uncover principles of regularity or exceptionality of delayed reception publications.  相似文献   

18.
ABSTRACT

This paper studies open innovation practices in Russian state-owned enterprises (SOEs). In 2011, the Russian Government set ambitious goals in science, technology and innovation, and uses its large SOEs as channels to achieve these targets. These initiatives focus on the collaboration among innovation actors and introduce open innovation (OI) principles. Based on a large-scale innovation survey, we compare private enterprises to state-owned peers and present selected case studies. Our data support the claim that Russian SOEs are driving the demand for technology and mainly absorb incoming OI activities. Different to their peers, SOEs extend their OI activities to the country’s knowledge producers, such as research and technology organisations (RTOs), and leading universities. They work on incorporating scientific knowledge that could, indeed, hold the key to globally competitive technological innovations, but also have better capabilities to include business partners.

Abbreviation : OI: Open innovation; SOE: State-owned enterprise; RTO: Research and technology organisation; STI: Science, technology and innovation.  相似文献   

19.
20.
We analyze the morphology evolution of the Ga doped ZnO(GZO) films deposited on quartz substrates by a laser deposition system. The surface morphologies of the film samples grown with different times are measured by the atomic force microscope, and they are analyzed quantitatively by using the image data. In the initial stage of the growth time shorter than 8 min, our analysis shows that the GZO surface morphologies are influenced by such factors as the random fluctuations, the smoothening effects in the deposition, the lateral strain and the substrate. The interface width uw(t) and the lateral correlation length ξ(t) at first decrease with deposition time t. For the growth time larger than 8 min, w(t) and ξ(t) increase with time and it indicates the roughening of the surface and the surface morphology exhibits the fractal characteristics. By fitting data of the roughness w(t) versus deposition time t larger than 4 min to the power-law function, we obtain the growth exponent β is 0.3; and by the height-height correlation functions of the samples to that of the self-affine fractal model, we obtain the value of roughness exponent α about 0.84 for all samples with different growth time t.  相似文献   

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