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1.
A study is described of the rank/JIF (Journal Impact Factor) distributions in the high-coverage Scopus database, using recent data and a three-year citation window. It includes a comparison with an older study of the Journal Citation Report categories and indicators, and a determination of the factors most influencing the distributions. While all the specific subject areas fit a negative logarithmic law fairly well, those with a greater External JIF have distributions with a more sharply defined peak and a longer tail—something like an iceberg. No S-shaped distributions, such as predicted by Egghe, were found. A strong correlation was observed between the knowledge export and import ratios. Finally, data from both Scopus and ISI were used to characterize the rank/JIF distributions by subject area.  相似文献   

2.
Journal impact factor (JIF) has been used for journal evaluation over a long time, but also accompanied by the continuing controversy. In this study, a new indicator, the Journal’s Integrated Impact Index (JIII) has been proposed for journal evaluation. In the JIII, one journal’s average citations per paper, total citations, and all journals’ average level of average citations per paper and total citations have been used to characterize the integrated impact of journals. Some contrastive analyses were carried out between JIII and JIF. The results show some interesting properties of the new indicator, and also reveal some relevant relationships among JIII, JIF, and other bibliometric indicators.  相似文献   

3.
The science and engineering base is a key source of knowledge for the development and use of Information and Communication Technologies (ICTs). In order to be able to effectively describe and monitor world-wide scientific activity related to ICTs, it is important to be able to provide reliable macro-level statistics of this knowledge base. International bibliographic databases and related bibliometric indicators together provide an analytical framework and appropriate measures to cover both the ‘supply side’—research capabilities and outputs—and ‘demand side’—collaboration, diffusion and citation impact—related to the ICT research. This paper presents results of such a bibliometric study describing macro-level features of this ICT knowledge base. The data were retrieved from a specially developedCWTS ICT Database which provides a broad-scope world-wide coverage of ICT-relevant research papers published in high-quality international scientific and technical journals. The cross-country comparison focuses on the level of scientific output and co-operation patterns of the most actively publishing nations with a focus on the three Triad zones—the European Union, the USA and Japan.  相似文献   

4.
A structural model with three compositional phases and two levels of hierarchical organization is proposed for predicting Young’s modulus of porous bones with microstructural variations and anisotropy based on their geometric similarity to metal foams. It has been shown that the proposed single model provides predictions of Young’s modulus with high accuracy up to ±30% for cortical and cancellous bones compared with measured data from the literature. In addition, the conversion of the solid bone shape from “Plate-like” to “Rod-like” at a porosity of 70% or higher (BV/TV 30% or lower)—verified by observations—can be predicted using the proposed model.  相似文献   

5.
The ISI journal impact factor (JIF) is based on a sample that may represent half the whole-of-life citations to some journals, but a small fraction (<10%) of the citations accruing to other journals. This disproportionate sampling means that the JIF provides a misleading indication of the true impact of journals, biased in favour of journals that have a rapid rather than a prolonged impact. Many journals exhibit a consistent pattern of citation accrual from year to year, so it may be possible to adjust the JIF to provide a more reliable indication of a journal’s impact.  相似文献   

6.
In the assessment of success of new analgesic drugs over the past 50 years (Kissin, Anesth Analg 110:780–789, 2010) we observed a difference in the publication response to a new drug between biomedical journals in general and top journals: number of published articles on a drug increased (and declined) more rapidly in the top journals. Based on this phenomenon we present a new publication indicator—the Top Journal Selectivity Index (TJSI). It represents the ratio between the number of all types of articles in the top 20 biomedical journals and the number of articles in all (>5,000) journals covered by Medline, over 5 years after a drug’s introduction. Ten analgesics developed during the period 1986–2009 were selected for analysis. Three publication indices were used for assessment: the number of all types of articles presented in Medline, the number of articles covering only randomized controlled trials (RCT), and the Top Journal Selectivity Index. We also assessed the success score in the development of these analgesics based on the following criteria: novelty of molecular target, analgesic efficacy, and response by the pharmaceutical market. The relationships between the publication indices and analgesic’s success score were determined with the use of the Pearson correlation coefficient. Positive relationship was found only with the Top Journal Selectivity Index (r = 0.876, p < 0.001). We suggest that this index can predict success in drug development at least in the field of analgesics.  相似文献   

7.
Résumé La fabrication des matériaux de construction nécessite des contr?les systématiques de qualité, en laboratoire. Il est tout aussi important de pouvoir effectuer des contr?lesin situ, une fois l’ouvrage terminé et dans le temps. La dynamostratigraphie apporte une solution à ces deux problèmes. Cette méthode est basée sur la mesure de l’effort de pénétration (R) d’un foret animé simultanément de mouvements de rotation (ϕ) et de translation (x) à des vitesses imposées. L’enregistrement de la variationR(x) permet de constater les variations de résistance mécanique et par là-même l’épaisseur des différents constituants traversés. Deux exemples d’utilisation de la dynamostratigraphie sont présentés à partir de mesures effectuées en laboratoire. Lorsque le matériau n’est pas stratifié—un mortier—la résistance à la pénétration permet de comparer différentes compositions (sable/ciment) et leurs évolutions au cours du séchage. Lorsque le matériau est hétérogène—un béton—la résistance à la pénétration décèle la taille des gravillons et la qualité du mortier. La dynamostratigraphie s’applique avec succès à tous les matériaux.
Summary The manufacture of building materials calls for systematic quality control in the laboratory. It is equally important to be able to carry out control on site, once the construction is completed, and then later during service. Dynamostratigraphy brings a solution to these two problems. This method is based on the measurement of the penetration force (R) of a drill driven simultaneously in rotation (ϕ) and sideways (x) at imposed rates. Recording the variation inR(x) indicates the variation in the mechanical resistance and thereby the thickness of the different constituents penetrated. Details are given of two examples of the use of dynamostratigraphy in the laboratory. When the material examined is not a stratified medium—a mortar—the resistance to penetration will give the possibility of comparing different design mixes (sand/cement) and their modification during drying. When the material is heterogeneous—concrete—the resistance to penetration defines the size of gravel and the quality of the mortar. In fact, dynamostratigraphy can be applied successfully to all materials.
  相似文献   

8.
Two broad classes of scientific impact indices are proposed and their properties - both theoretical and practical — are discussed. These new classes were obtained as a geometric generalization of the well-known tools applied in scientometric, like Hirsch’s h-index, Woeginger’s w-index and the Kosmulski’s Maxprod. It is shown how to apply the suggested indices for estimation of the shape of the citation function or the total number of citations of an individual. Additionally, a new efficient and simple O(log n) algorithm for computing the h-index is given.  相似文献   

9.
Article-count impact factor of materials science journals in SCI database   总被引:2,自引:0,他引:2  
This article proposed a new index, so-called “Article-Count Impact Factor” (ACIF) for evaluating journal quality in light of citation behaviour in comparison with the ISI journal impact factors. The ACIF index was the ratio of the number of articles that were cited in the current year to the source items published in that journal during the previous two years. In this work, we used 171 journal titles in materials categories published in the years of 2001–2004 in international journals indexed in the Science Citation Index Expanded (SCI) database as data source. It was found that ACIF index could be used as an alternative tool in assessing the journal quality, particularly in the case where the assessed journals had the same (equal or similar) JIF values. The experimental results suggested that the higher the ACIF value, the more the number of articles being cited. The changes in ACIF values were more dependent on the JIF values rather than the total number of articles. Polymer Science had the greatest ACIF values, suggesting that the articles in Polymer Science had greater “citation per article” than those in Metallurgical Engineering and Ceramics. It was also suggested that in order to increase a JIF value of 1.000, Ceramics category required more articles to be cited as compared to Metallurgical Engineering and Polymer Science categories.  相似文献   

10.
This paper presents the results of an exploratory bibliometric study aiming at an analysis of basic high energy physics (HEP) research impact on fields other than physics, and particularly on application-oriented R&D. After a general discussion of an extensive citation analysis of basic research publications from three HEP institutes—CERN, DESY, and SLAC—the paper focuses on the ‘knowledge flow’ from physics to non-physics, and more specifically the flow from basic physics research to the ‘applied world’. At this level, we report journal- as well as research field characteristics, and we identify the most frequently citing R&D groups. We conclude that DESY is most cited by the ‘applied world’, followed by SLAC and CERN. If the number of journals that institutes have in common—whether based on the source or the citing publication—is taken as an indicator of the resemblance of their research interests, we found that CERN and SLAC have the closest resemblance, followed by SLAC and DESY, with CERN and DESY having the least in common.  相似文献   

11.
Evitherm is a web-based thermal resource centre, resulting from a 3-year project partly funded by the EU’s GROWTH programme (2002–05). Evitherm links together the widely distributed centres of excellence (NMIs, research and teaching institutes, consultants, etc.) and others concerned with thermal measurements and technology to provide a focal point for information exchange and knowledge transfer between all these organizations and industry. To facilitate the quick and easy flow of thermal knowledge to users of thermal technologies, evitherm has a website (www.evitherm.org) through which it disseminates information and by which it also provides access to resources such as training, property data, measurements and experts. Among the resources available from the website are (1) thermal property data—offering access to some of the world’s leading databases; (2) expertise— evitherm has a database of consultants, an Advice line, a public Forum and a unique Consultancy Brokering Service whereby users are linked to the expert they need to solve their thermal industrial problems; (3) industry resources—thermal information for particular industry sectors; (4) services—information directories on thermal property measurement, training, equipment supply, reference materials, etc.; (5) literature—links to books, papers, standards, etc.; (6) events—conferences, meetings, seminars, organizations and networks, what’s happening. A user only has to register (for free) to gain access to all the information on the evitherm website. Much of the thermal property data can be accessed for free and in a few cases we have negotiated affordable rates for access to some leading databases, such as CINDAS, THERSYST and NELFOOD. This article illustrates the aims and structure of the evitherm Society, how it is directed, and how it serves the thermal community worldwide in its need for quick and easy access to the resources needed to help ensure a well resourced industrial work force and clean and efficient thermal processes.  相似文献   

12.
Currently the Journal Impact Factors (JIF) attracts considerable attention as components in the evaluation of the quality of research in and between institutions. This paper reports on a questionnaire study of the publishing behaviour and researchers preferences for seeking new knowledge information and the possible influence of JIF on these variables. 54 Danish medical researchers active in the field of Diabetes research took part. We asked the researchers to prioritise a series of scientific journals with respect to which journals they prefer for publishing research and gaining new knowledge. In addition we requested the researchers to indicate whether or not the JIF of the prioritised journals has had any influence on these decisions. Furthermore we explored the perception of the researchers as to what degree the JIF could be considered a reliable, stable or objective measure for determining the scientific quality of journals. Moreover we asked the researchers to judge the applicability of JIF as a measure for doing research evaluations. One remarkable result is that app. 80% of the researchers share the opinion that JIF does indeed have an influence on which journals they would prefer for publishing. As such we found a statistically significant correlation between how the researchers ranked the journals and the JIF of the ranked journals. Another notable result is that no significant correlation exists between journals where the researchers actually have published papers and journals in which they would prefer to publish in the future measured by JIF. This could be taken as an indicator for the actual motivational influence on the publication behaviour of the researchers. That is, the impact factor actually works in our case. It seems that the researchers find it fair and reliable to use the Journal Impact Factor for research evaluation purposes.  相似文献   

13.
This article reports for first time the state of science and technology in the African Continent on the basis of two scientometric indicators — number of research publications and number of patents awarded. Our analysis shows that Africa produced 68,945 publications over the 2000–2004 period or 1.8% of the World’s publications. In comparison India produced 2.4% and Latin America 3.5% of the World’s research. More detailed analysis reveals that research in Africa is concentrated in just two countries — South Africa and Egypt. These two counties produce just above 50% of the Continent’s publications and the top eight countries produce above 80% of the Continent’s research. Disciplinary analysis reveals that few African countries have the minimum number of scientists required for the functioning of a scientific discipline. Examination of the Continent’s inventive profile, as manifested in patents, indicates that Africa produces less than one thousand of the world’s inventions. Furthermore 88% of the Continent’s inventive activity is concentrated in South Africa. The article recommends that the African Governments should pay particular attention in developing their national research systems.  相似文献   

14.
The article describes the method for the online determination of the journal impact factor (JIF). The method is very simple and can be used both for the ISI defined journal impact factor and for the calculation of other generalised journal impact factors. But the direct online method fails for non-ISI journals i.e. journals not indexed by ISI to the three citation databases. For such journals only the “External Cited Impact Factor” associated with citations from ISI journals (ECIFisi) can be determined online by the common method. As an extra benefit the online method makes available the determination of the geographical distribution of citations and citable units in relation to any given JIF, i.e. the international impact for a particular journal in a given year. The method is illustrated by calculating the generalised JIF, self-citations and ECIF(isi) as well as the international impact for Journal of Documentation and Scientometrics.  相似文献   

15.
This paper deals with the determination of unknown heating temperatures and temperature distributions on the upper surface of a thin circular plate, defined as 0 ≤ r ≤a, —b/2 ≤zb/2. The expressions of unknown heating temperatures and temperature distributions are obtained in series form, involving Bessel’s functions with the help of the integral transform technique. Thermoelastic deformations are discussed with the help of temperature and are illustrated numerically.  相似文献   

16.
M Goldshtik  F Hussain  R J Yao 《Sadhana》1997,22(3):323-367
By exploiting three unique characteristics of confined swirling incompressible flows — centrifugal acceleration, internal separation or recirculation zones near the axis, andbistability (i.e. rarefied and condensed stable states) of multi-phase flows — we developed several innovativevortex machines which will revolutionize mechanical technologies in a variety of industries. The machines utilizing these features include:Vortex Engine, Vortex Thruster, Vortex Suction Device, Vortex Chemical Reactor, Bubbling Centrifuge andVortex Mill. As a specific example, we describe here in some detail the development of a liquid piston engine, including analysis of its hydrodynamic and thermodynamic features. We have designed a laboratory ‘cold’ model and performed detailed experimental, theoretical and numerical analyses to study the role of the controlling parameters and are now ready to test a ‘hot’ model. In addition, we mention a few other vortex technologies of interest to us. A list of symbols used appears at the end of the paper.  相似文献   

17.
There is general consensus that the field of nanotechnology will be very important in the future. An open question is, however, which technological approaches or paradigms will be important in the field. The paper assumes that the carbon nanotube will be a key element of an emerging technological paradigm in nanotechnology. This study employs a bibliometric method — bibliographic coupling — to identify important nanotubes-related ‘leitbilder’ — a concept meaning ‘guiding images’ that provide a basis for different professions and disciplines to work in the same direction. Until recently, bibliographic coupling has been applied rarely for purposes of research evaluation, not to mention technology foresight. Our case study seems to suggest that bibliographic coupling is particularly suitable for anticipating technological breakthroughs. Bibliographic coupling analysis of recent nanotube-related patents focused our attention to recent patents owned by Nantero Inc. Nantero’s main focus is the development of NRAM — a high-density nonvolatile random access memory. The NRAM leitbild seems to be an important emerging leitbild. It connects technical opportunities and promising applications relating to the memories in devices such as cell phones, MP3 players, digital cameras, as well as applications in networking arena.  相似文献   

18.
Hirsch-index for countries based on Essential Science Indicators data   总被引:7,自引:0,他引:7  
The authors present ranked lists of world’s countries — with main focus on EU countries (together with newly acceeded and candidate countries) — by their h-index on various science fields. As main source of data Thomson Scientific’s Essential Science Indicators (ESI) database was used. EU countries have strong positions in each field but none of them can successfully compete with the USA. The modest position of the newly accessed and candidate countries illustrate the importance of supportive economic and political background in order to achieve scientific success. An attempt is made to fit a recent theoretical model relating the h-index with two traditional scientometric indicators: the number of publications and the mean citation rate.  相似文献   

19.
Freek Wiedijk 《Sadhana》2009,34(1):193-220
A small project in which I encoded a proof of Arrow’s theorem—probably the most famous results in the economics field of social choice theory—in the computer using the Mizar system is presented here. The details of this specific project, as well as the process of formalization (encoding proofs in the computer) in general are discussed.  相似文献   

20.
Skeletal tissues as nanomaterials   总被引:1,自引:0,他引:1  
Collagen is the most abundant protein in the body and, though the fibre-forming collagens have a ‘common’ structure, it is adapted to perform a large range of functions—from the differing mechanical needs of tendon versus bone to forming a transparent support structure in the cornea. This perfidy also suggests that collagen could form a generic basis for a range of scaffold needs for tissue engineering or medical device coating applications. We at the London Centre for Nanotechnology—a joint venture between University College London and Imperial College—are taking a bottom-up approach having decided that many of the ‘accepted dogmas’ of collagen biology may not be quite as soundly based as currently held. We are using several of the tools of ‘hard’ nanotechnology—such as atomic force microscopy—to re-examine collagen structure with the longer term aim of using such information to design materials with appropriate physical attributes. Examples of our current research on mineralised and soft tissue collagens are presented.  相似文献   

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