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1.
Sangwal K 《Scientometrics》2012,92(3):575-591
A general expression based on the concepts of the progressive nucleation mechanism is proposed in the form [Formula: see text] to describe the growth behavior of items in an individual system and a collective of systems. In the above relation, α(t) is the ratio of items N(t) at time t to the maximum number C of possible items for the system, Θ is the corresponding time constant and q is the exponent. The above relation is then used to analyze: (1) the growth behavior of cumulative number N(t) of papers published by individual authors and cumulative citations L(t) of N(t) papers of an author as a function of citation duration t, and (2) the relationship between cumulative citations L(t) of papers and cumulative number N(t) of papers. The proposed approach predicts that: (1) the fraction of items produced by successive systems is additive, (2) the cumulative fraction α(sum)(t) of maximum number of sites is the sum of contributions of fractions of maximum number of items produced by different systems, and (3) the values of time constants Θ and exponent q increase with the addition of fraction of items produced by subsequent systems, but their values are the lowest for individual systems. The approach is applied to explain the growth behavior of cumulative N(t) papers and L(t) citations of four selected Polish professors.  相似文献   

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The number of citations of journal papers is an important measure of the impact of research. Thus, the modeling of citation behavior needs attention. Burrell, Egghe, Rousseau and others pioneered this type of modeling. Several models have been proposed for the citation distribution. In this note, we derive the most comprehensive collection of formulas for the citation distribution, covering some 17 flexible families. The corresponding estimation procedures are also derived by the method of moments. We feel that this work could serve as a useful reference for the modeling of citation behavior.  相似文献   

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The senior author is usually last on the byline of scientific publications, yet generally has made the second most important contribution. The explosion in author number per scientific paper, has necessitated limits on the number of authors allowed in cited references, frequently resulting in senior author truncation. Would potential visibility gained from citations in top-tier journals be offset by senior author omission? We found evidence for this in a sample of 208 journals, showing significant associations between author limits in cited references and various measures of journal quality. These associations, however, differed among biological science, physical science, and interdisciplinary journals.  相似文献   

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Under the sponsorship of the U.S. National Science Foundation, CHI Research, Inc. developed the bibliometric indicators for the U.S. National Science Board'sScience Indicators Reports starting withScience Indicators 1972. In the work reported here, for the Commission of the European Communities, CHI has extended the Science Indicators techniques and database to a study of publication, coauthorship and citation within 28 scientific fields related to various European Community programs.Perhaps the most important finding of the research was that internationally coauthored papers — papers authored by scientists affiliated with institutions in more than one EC country — were cited two times as highly as papers authored by scientists working at a single institution within a single country. These EC-EC internationally coauthored papers were cited as highly as EC-Non EC and Non-EC papers. This indicates that the internationally linked European science is of as high impact as any other science in the world.A second key finding was that, after compensating for national scientific size, the degree of international coauthorship did not appear to be particularly dependent upon size. However, linguistic and cultural factors were found to be very strong. The patterns of coauthorship amongst the European countries are far from homogeneous, and are quite heavily affected by linguistic, historical, and cultural factors.Finally, it was found that international coauthorship is increasing steadily, both within and outside of the Community, with some evidence that international cooperation is increasing more rapidly in scientific fields that have been targeted by the Commission.This work has been sponsored by the MONITOR programme of the Commission of the European Communities.  相似文献   

6.
Gong  Kaile  Xie  Juan  Cheng  Ying  Larivière  Vincent  Sugimoto  Cassidy R. 《Scientometrics》2019,120(3):1439-1460

Contemporary scientific exchanges are international, yet language continues to be a persistent barrier to scientific communication, particularly for non-native English-speaking scholars. Since the ability to absorb knowledge has a strong impact on how researchers create new scientific knowledge, comprehensive access to and understanding of both domestic and international scientific publications is essential for scientific performance. This study explores the effect of absorbed knowledge on research impact by analyzing the relationship between the language diversity of cited references and the number of citations received by the citing paper. Chinese social sciences are taken as the research object, and the data, 950,302 papers published between 1998 and 2013 with 8,151,327 cited references, were collected from the Chinese Social Sciences Citation Index. Results show that there is a stark increase in the consumption of foreign language material within the Chinese social science community, and English material accounts for the vast majority of this consumption. Papers with foreign language references receive significantly more citations than those without, and the citation advantage of these internationalized work holds when we control for characteristics of the citing papers, such as the discipline, prestige of journal, prestige of institution, and scientific collaboration. However, the citation advantage has decreased from 1998 to 2008, largely as an artifact of the increased number of papers citing foreign language material. After 2008, however, the decline of the citation advantage subsided and became relatively stable, which suggests that incorporating foreign language literature continues to increase scientific impact, even as the scientific community itself becomes increasingly international. However, internationalization is not without concerns: the work closes with a discussion of the potential problems associated with the lack of linguistic diversity in scientific communication.

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The effect of highly cited papers on national citation indicators   总被引:3,自引:3,他引:0  
Aksnes  Dag W.  Sivertsen  Gunnar 《Scientometrics》2004,59(2):213-224
Scientometrics - Citation distributions are extremely skewed. This paper addresses the following question: To what extent are national citation indicators influenced by a small minority of highly...  相似文献   

9.
Ding  Yang  Dong  Xianlei  Bu  Yi  Zhang  Bin  Lin  Kexin  Hu  Beibei 《Scientometrics》2021,126(9):7609-7621
Scientometrics - Downloads and citations of papers are regarded as significant metrics of the academic level of researchers and the influence of journals. Besides, exploring the association between...  相似文献   

10.
Lee  Danielle H. 《Scientometrics》2019,118(1):281-304
Scientometrics - This paper aims to determine the factors significantly predicting the future citation rates of conference papers. Whereas a large body of bibliometric studies has investigated the...  相似文献   

11.
X-ray diffraction analysis was used to study changes in the distribution of stresses of the first and the second kind in surface layers of stressed Cr18Ni10Ti steel specimens during the nucleation and growth of corrosion cracks. Based on the results obtained, a mechanism of nucleation of corrosion cracks in 18-8-type steels was postulated.  相似文献   

12.
Larsen  Birger 《Scientometrics》2002,54(2):155-178
A new citation search strategy is proposed for Information Retrieval (IR) based on the principle of polyrepresentation (Ingwersen, 1992, 1996). The strategy exploits logical overlaps between a range of cognitively different interpretations of the same documents in a structured manner, i.e. so-called cognitive overlaps of representations. The strategy is essentially a "cycling strategy" starting with documents retrieved by a subject search, wherefrom new documents are identified automatically by following the network of citations in scientific papers backwards and forwards in time. In contrast to earlier citation search strategies the proposed strategy does not require known relevant documents (seed documents) as a starting point, but may be based on a subject search. A pilot study is reported where the ability of the strategy to retrieve additional relevant documents is analysed. Results show that a very large amount of documents can be retrieved by the strategy, and that these may be segmented in a number of distinct "overlap levels". It is demonstrated that the combined core of the higher-level overlaps contains higher relevance density than found in the original retrieval results. Based on these results it is suggested that the documents be displayed in order of their presence in higher-level overlaps, so as to maximise the chances that as many relevant documents as possible will be presented first to a user. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

13.
Ravikumar  S.  Boruah  Bidyut Bikash  Ravikumar  M. N. 《Scientometrics》2022,127(8):4873-4885
Scientometrics - In this paper, the correlation of the citation count and Mendeley readership score of the articles by the Sri Lankan authors was studied. The study presents how the correlation...  相似文献   

14.
The citation motivations among 51 self citing authors in several natural science disciplines were investigated. Results of a survey on reasons for both self citation and citation to others show that there are very few differences in motivation, and that there are plausible intellectual grounds for those differences which are substantial. Analysis of exposure in text reveals virtually no differences between self citations and citations to others. Analysis of individual disciplines also uncover no substantive differences in either motivation or exposure in text.  相似文献   

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Quasi-static axial compression behavior of cellular materials can be explained by two ideal deformation scenarios: homogeneous deformation and progressive collapse. An elastic–plastic–rigid (E–P–R) foam model is used to derive the energy absorbed under these two deformation scenarios. It has been identified that the progressive collapse mode of deformation can absorb more energy than homogeneous deformation prior to full densification. The additional energy is shown to be proportional to the magnitude of the tangent modulus in the plateau region of the stress–strain curve. The model also shows that energy absorption is equivalent for all deformation states of progressive and homogenous collapse for materials that exhibit elastic–perfectly-plastic–rigid behavior.  相似文献   

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This paper identifies the main references, authors and journals influencing the sustainable development literature. The task is accomplished by means of a citation analysis based on the records of ISI Web of Science. We found that the core of sustainability thinking is framed by a pattern of landmark studies published around every 5 years. Only 380 publications have been cited at least ten times. References with the highest influence are those with a global dimension and large diffusion, such as Brundtland Commission’s “Our common future” (1987) and classics such as Meadows’ et al. “Limits to growth” (1972). The list of the most influential references over the period 1960–2005 is dominated by contributions from economics (particularly ecological economics) and environmental science, but includes many other disciplines such as urban planning, political sciences and sociology. References are also made to policy documents such as “Agenda 21”, one of the main outcomes of the Rio Summit in 1992. In analyzing citation trends, we found that classics, because of their high rates of citations per year, seem to have a more enduring and stable influence.  相似文献   

18.
A microscopic model based on the appearance, diffusion, and aggregation of point defects allows to calculate the time of appearance of the first nucleus on a surface during a reaction between a solid and a gas. Calculated distributions of these times of appearance of the first nucleus are qualitatively compared to experimental ones, previously determined. The appearance of the point defects seems to be the most influential step on the time of appearance of the first nucleus. Moreover the comparison between experimental and calculated distributions allows to conclude that the frequency of appearance of the defects is higher on the edges than on the faces of the single crystal.  相似文献   

19.
A hypothesis on heterogeneous nucleation in a liquid volume is used as a basis for obtaining a relation to close a system of equations which describes non equilibrium discharge.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 46, No. 3, pp. 371–375, March, 1984.  相似文献   

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