On a family of diophantine triples {K,A 2 K + 2A, (A + 1)2 K + 2(A + 1)} with two parameters II

Periodica Mathematica Hungarica
Authors: Bo He and Alain Togbé

Abstract

Let A and k be positive integers. In this paper, we study the Diophantine quadruples

\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$\{ k,A^2 k + 2A,(A + 1)^2 k + 2(A + 1)d\} .$$ \end{document}
If d is a positive integer such that the product of any two distinct elements of the set increased by 1 is a perfect square, then
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$\begin{gathered} d = (4A^4 + 8A^3 + 4A^2 )k^3 + (16A^3 + 24A^2 + 8A)k^2 + \hfill \\ + (20A^2 + 20A + 4)k + (8A + 4) \hfill \\ \end{gathered}$$ \end{document}
for A ≥ 52330 and any k. This extends our result obtained in [4].

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On Templeman averages and variation functions

Periodica Mathematica Hungarica
Author: R. Nair

Abstract

Let S be a countable semigroup acting in a measure-preserving fashion (gT g) on a measure space (Ω, A, µ). For a finite subset A of S, let |A| denote its cardinality. Let (A k)k=1 be a sequence of subsets of S satisfying conditions related to those in the ergodic theorem for semi-group actions of A. A. Tempelman. For A-measureable functions f on the measure space (Ω, A, μ) we form for k ≥ 1 the Templeman averages

\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$\pi _k (f)(x) = \left| {A_k } \right|^{ - 1} \sum\nolimits_{g \in A_k } {T_g f(x)}$$ \end{document}
and set V q f(x) = (Σk≥1|π k+1(f)(x) − π k(f)(x)|q)1/q when q ∈ (1, 2]. We show that there exists C > 0 such that for all f in L 1(Ω, A, µ) we have µ({x ∈ Ω: V q f(x) > λ}) ≤ C(∫Ω | f | dµ/λ). Finally, some concrete examples are constructed.

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Quasilinearity of some composite functionals associated to Schwarz’s inequality for inner products

Periodica Mathematica Hungarica
Authors: S. Dragomir and Anca Goşa

Abstract

The quasilinearity of certain composite functionals associated to Schwarz’s celebrated inequality for inner products is investigated. Applications for operators in Hilbert spaces are given as well.

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Some examples of Hermitian surfaces

Periodica Mathematica Hungarica
Author: Jaeman Kim

Abstract

The Riemannian version of the Goldberg-Sachs theorem says that a compact Einstein Hermitian surface is locally conformal Kähler. In contrast to the compact case, we show that there exists an Einstein Hermitian surface which is not locally conformal Kähler. On the other hand, it is known that on a compact Hermitian surface M 4, the zero scalar curvature defect implies that M 4 is Kähler. Contrary to the compact case, we show that there exists a non-Kähler Hermitian surface with zero scalar curvature defect.

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Strong representations of the polycyclic inverse monoids: Cycles and atoms

Periodica Mathematica Hungarica
Authors: D. Jones and M. Lawson

Abstract

This paper was inspired by a monograph by Bratteli and Jorgensen, and the work of Kawamura. We introduce two new semigroups: a wide inverse submonoid of the polycyclic inverse monoid, called the gauge inverse monoid, and a Zappa-Szép product of an arbitrary free monoid with the free monoid on one generator. Both these monoids play an important role in studying arbitrary, not necessarily transitive, strong actions of polycyclic inverse monoids. As a special case of such actions, we obtain some new results concerning the strong actions of P 2 on ℤ determined by the choice of one positive odd number. We explain the role played by Lyndon words in characterising these repesentations and show that the structure of the representation can be explained by studying the binary representations of the numbers

\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$\frac{1} {p},\frac{2} {p}, \ldots \frac{{p - 1}} {p}$$ \end{document}
. We also raise some questions about strong representations of the polycyclic monoids on free abelian groups.

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The comprehensive competitiveness evaluation of American universities in Bridge Engineering

Scientometrics
Authors: Yuan Wang, Ruimin Ma, Tianhao Tang, Xia Liu, Ping Xie, Jianxin Wang, Jianxiang Liu, Haideng Zhou and Siwei Zhang

Abstract

This article explores a method of evaluating the comprehensive competitiveness of American universities in Bridge Engineering, which is beneficial for students’ picking up an ideal university for further study in America. Making use of ESI database, SCI database and EI database as well as the ranking of American universities from U.S. News and World Report, the author evaluates the comprehensive competitiveness of American universities in Bridge Engineering, and then develops the ranking of comprehensive competitiveness of American universities in Bridge Engineering specialty. From the ranking, the author reaches the conclusion that American universities such as University of Illinois-Urbana-Champaign and Georgia Institute of Technology and so on, have comparatively higher international influence and competitiveness in the field of Bridge Engineering.

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A deductive approach to select or rank journals in multifaceted subject, Oceanography

Scientometrics
Authors: Satya Ranjan Sahu and Krushna Chandra Panda

Abstract

Whether singleton approach (citation analysis of identified source journals) used by Gross and Gross (Science 66(1713):385–389, ) or differential approach (citation analysis of articles in specific subject field) applied by Bradford (Engineering 137:85–86, ) suitable to select or rank journals in multifaceted subject—‘Oceanography’ is presented. This study discusses both the approaches analyzing citations of published literature in oceanography from 30 countries. The ranking correlation of journals showed better positive correlation (lowest ρ = 0.662 for 2005–2009 to highest ρ = 0.817 for 1995–1999) when top ranked journals from the list generated complying Gross and Gross approach (GA) were correlated with same journal titles of the list generated complying Bradford approach than the other way (lowest ρ = 0.588 for 2005–2009 to highest ρ = 0.726 for 1990–1994). Both the approaches matched similar number of journals to country-wise lists and give unbiased choice in preferring a ranking list. The journals distribution graphs showed typical Bradford–Leimkuhler curves in both the approaches for all the datasets. But the groos droop appears comparatively early with shorter straight line in GA. The high clustering of literature to limited number of journals is a disadvantage in multifaceted subject. So the differential approach used by Bradford is being considered suitable for multifaceted subject like, ‘Oceanography’.

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The role of core documents in bibliometric network analysis and their relation with h-type indices

Scientometrics
Author: Wolfgang Glänzel

Abstract

The notion of core documents and their application is discussed in the context of scientometric networks. An interesting solution of the problem of the arbitrariness of thresholds emerges from the application of Hirsch-type indices to dense networks as are typically observed in local clustering. Examples from several disciplines in the sciences and social sciences illustrate how these core vertices can be determined using this approach, and visualise how core documents are applied to represent the internal structure of the complete network or of parts of it.

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Using complex networks concepts to assess approaches for citations in scientific papers

Scientometrics
Authors: D. R. Amancio, M. G. V. Nunes, O. N. Oliveira Jr. and L. da F. Costa

Abstract

The number of citations received by authors in scientific journals has become a major parameter to assess individual researchers and the journals themselves through the impact factor. A fair assessment therefore requires that the criteria for selecting references in a given manuscript should be unbiased with regard to the authors or journals cited. In this paper, we assess approaches for citations considering two recommendations for authors to follow while preparing a manuscript: (i) consider similarity of contents with the topics investigated, lest related work should be reproduced or ignored; (ii) perform a systematic search over the network of citations including seminal or very related papers. We use formalisms of complex networks for two datasets of papers from the arXiv and the Web of Science repositories to show that neither of these two criteria is fulfilled in practice. By representing the texts as complex networks we estimated a similarity index between pieces of texts and found that the list of references did not contain the most similar papers in the dataset. This was quantified by calculating a consistency index, whose maximum value is one if the references in a given paper are the most similar in the dataset. For the areas of “complex networks” and “graphenes”, the consistency index was only 0.11–0.23 and 0.10–0.25, respectively. To simulate a systematic search in the citation network, we employed a traditional random walk search (i.e. diffusion) and a random walk whose probabilities of transition are proportional to the number of the ingoing edges of the neighbours. The frequency of visits to the nodes (papers) in the network had a very small correlation with either the actual list of references in the papers or with the number of downloads from the arXiv repository. Therefore, apparently the authors and users of the repository did not follow the criterion related to a systematic search over the network of citations. Based on these results, we propose an approach that we believe is fairer for evaluating and complementing citations of a given author, effectively leading to a virtual scientometry.

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The evaluation of Indian cancer research, 1990–2010

Scientometrics
Authors: Grant Lewison and Philip Roe

Abstract

Cancer research outputs in India have expanded greatly in recent years, with some concomitant increase in their citation scores. Part of the increase in output is attributable to greater coverage in the Web of Science of Indian journals, which are more clinical than international ones, and much less often cited. Other measures of esteem have also increased, such as the percentage of reviews and the immediacy with which Indian cancer articles are cited. Most of the output came from just nine of the 35 Indian states and Union Territories, led by New Delhi and Maharashtra. The distribution of the amount of research by cancer site correlates moderately positively with the relative disease burden, with mouth (head and neck) cancer (often caused by the chewing of tobacco or areca, betel or paan) causing the highest number of deaths and also being well researched. We also analysed the articles by type of research, with articles in genetics and chemotherapy being the most numerous. For articles published in 2009–2010, data were available on the funding acknowledgements, and we found, as expected, that articles in clinical subjects were less often supported by external funding than ones in basic research. The major source of support was the Government of India, with relatively small contributions from charities and industry, unlike the situation in the UK and other western European countries.

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Positive and negative aspects of citation indices and journal impact factors

Scientometrics
Author: Alexandru T. Balaban

Abstract

The Hirsch citation index h is nowadays the most frequently used numerical indicator for the performance of scientists as reflected in their output and in the reaction of the scientific community reflected in citations of individual contributions. A few of the possible improvements of h are briefly reviewed. Garfield's journal impact factor (IF) characterizes the reaction of the scientific community to publications in journals, reflected in citations of all papers published in any given journal during the preceding 2 years, and normalized against all citable articles during the same period. Again, a few of the possible improvements or supplements of IF are briefly reviewed, including the journal-h index proposed by Braun, Glänzel, and Schubert. Ascribing higher weighting factors to citations of individual papers proportionally to IF is considered to be a misuse of useful numerical indices based on citations. At most, one could turn this argument on its head and one can find reasons to ascribe an inverse proportionality relative to IF for individual citations: if a paper is considered worthy to be cited even if it was published in a low-IF journal, that citation ought to be worth more than if the citation would have been from a higher-impact journal. A weight factor reflecting the prestige of the citing author(s) may also be considered.

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Testing differences statistically with the Leiden ranking

Scientometrics
Authors: Loet Leydesdorff and Lutz Bornmann

Abstract

The Leiden ranking 2011/2012 provides the Proportion top-10% publications (PP top-10%) as a new indicator. This indicator allows for testing performance differences between two universities for statistical significance.

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Exploring Web keyword analysis as an alternative to link analysis: a multi-industry case

Scientometrics
Authors: Liwen Vaughan and Esteban Romero-Frías

Abstract

The study explored the feasibility of using Web keyword analysis as an alternative to link analysis and tested the feasibility in a multi-industry environment. The keyword is the organization's name, in this case the company name. American companies from five industries were included in the study. The study found that the Web visibility of a company as measured by the number of Webpages on which the company name appears correlates with the company's business measures (revenue, profits, and assets). The correlation coefficients are similar to that between the inlink counts and the business measures. This suggests that the keyword count (searched by the company name) could replace inlink count as an alternative indicator of some commonly used business measures. The co-word (the co-occurrence of the names of two companies on Webpages) count was used as a measure of the relatedness of the two companies. Multidimensional scaling (MDS) analysis was applied to the co-word matrices and generated MDS maps that showed relationships among companies in a multi-industry context. Keyword data were collected from three different types of Websites (general Websites, blog sites, and Web news sites) and results were compared. The study found blog sites to be the better source to collect data for this type of study. The comparison of MDS maps generated from co-link data and the blog co-word data showed that the co-word analysis is as effective as co-link analysis in mapping business relationships. The value of the study is not limited to the business sector as the co-word method could be applied to analysing relationships among other types of organizations.

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Optimal and hierarchical clustering of large-scale hybrid networks for scientific mapping

Scientometrics
Authors: Xinhai Liu, Wolfgang Glänzel and Bart De Moor

Abstract

Previous studies have shown that hybrid clustering methods based on textual and citation information outperforms clustering methods that use only one of these components. However, former methods focus on the vector space model. In this paper we apply a hybrid clustering method which is based on the graph model to map the Web of Science database in the mirror of the journals covered by the database. Compared with former hybrid clustering strategies, our method is very fast and even achieves better clustering accuracy. In addition, it detects the number of clusters automatically and provides a top-down hierarchical analysis, which fits in with the practical application. We quantitatively and qualitatively asses the added value of such an integrated analysis and we investigate whether the clustering outcome provides an appropriate representation of the field structure by comparing with a text-only or citation-only clustering and with another hybrid method based on linear combination of distance matrices. Our dataset consists of about 8,000 journals published in the period 2002–2006. The cognitive analysis, including the ranked journals, term annotation and the visualization of cluster structure demonstrates the efficiency of our strategy.

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Scientometrics
Author: Joaquín M. Azagra-Caro

Abstract

Access to public knowledge is a prerequisite for the good functioning of developed economies. Universities strive and are also requested to contribute to this knowledge both locally and internationally. Traditional studies on the geography of knowledge flows have identified a localisation effect; however, these studies do not use the country as the unit of observation and hence do not explore national patterns. In this paper, we hypothesise that the localisation of university knowledge flows is directly related to share of firm expenditure on research and development. To test this hypothesis, we use references to universities in patent documents as indicators based on a data set of around 20,000 university references, for 37 countries in the period 1990–2007, resulting in panels of around 300–500 observations. We build indicators for the university knowledge flows both inside and outside the applicant country, which we explain as a function of some proxies for national size and research structure based on econometric estimations. We draw some conclusions as to the importance of national business scientific strength for fostering increased domestic university knowledge flows.

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Metrics to evaluate research performance in academic institutions: a critique of ERA 2010 as applied in forestry and the indirect H2 index as a possible alternative

Scientometrics
Authors: Jerome K. Vanclay and Lutz Bornmann

Abstract

Excellence for Research in Australia (ERA) is an attempt by the Australian Research Council to rate Australian universities on a 5-point scale within 180 Fields of Research using metrics and peer evaluation by an evaluation committee. Some of the bibliometric data contributing to this ranking suffer statistical issues associated with skewed distributions. Other data are standardised year-by-year, placing undue emphasis on the most recent publications which may not yet have reliable citation patterns. The bibliometric data offered to the evaluation committees is extensive, but lacks effective syntheses such as the h-index and its variants. The indirect H2 index is objective, can be computed automatically and efficiently, is resistant to manipulation, and a good indicator of impact to assist the ERA evaluation committees and to similar evaluations internationally.

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Response to Chuang and Ho's comments on “a bibliometric study of the trend in articles related to eutrophication published in Science Citation Index”

Scientometrics
Authors: Yi Huang and Jie Wang

Abstract

This note is a response Chuang and Ho's comments regarding to the appropriate selection of keywords for a bibliometric study entitled “a bibliometric study of the trend in articles related to eutrophication published in Science Citation Index” published in Scientometrics. Chuang's inquiry was Huang and Yi's careless use of filter, which had committed inaccurate results and wrong conclusions. This short note will explain the authors’ arguments to Chuang and Ho's inquiry in two folds, the conceptual analysis of keywords selection, and bibliometric comparison between ‘eutrophication’ and ‘eutrophication and eutrophic’.

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Where demographics meets scientometrics: towards a dynamic career analysis

Scientometrics
Authors: Lin Zhang and Wolfgang Glänzel

Abstract

In an earlier exercise some demographic methods were reformulated for application in a scientometric context. Age-pyramids based on annual publication output and citation impact was supplemented by the change of the mean age of the publications in the h-core at any time. Although the method was introduced to shed some demographic–scientometric light on the career of individual researchers, the second component, i.e., the age dynamics of the h-core can however be applied to higher levels of aggregation as well. However, the found paradigmatic shapes and patterns do not only characterise individual careers and positions, but are also typical of life cycles and subject-specific peculiarities. In the present study, the proposed approach is used to visualise the careers of scientists active in different fields of the sciences and social sciences and notably the second component, the h-core dynamics, is extended to the analysis of scientific journals from the same fields. In addition to the dynamics of productivity and citation impact, the evolution of co-authorship patterns of the same scientists is studied to capture another facet of individual academic careers.

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On the age-independent publication index

Scientometrics
Author: Keshra Sangwal

Abstract

It is shown that the age-independent index based on h-type index per decade, called hereafter an α index instead of the a index, suggested by Kosmulski (Journal of Informetrics 3, 341–347, ) and Abt (Scientometrics ) is related to the square-root of the ratio of citation acceleration a to the Hirsch constant A.

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Homotopical complexity of 2D billiard orbits

Studia Scientiarum Mathematicarum Hungarica
Authors: Lee Goswick and Nándor Simányi

Traditionally, rotation numbers for toroidal billiard flows are defined as the limiting vectors of average displacements per time on trajectory segments. Naturally, these creatures live in the (commutative) vector space ℝn, if the toroidal billiard is given on the flat n-torus. The billiard trajectories, being curves, often getting very close to closed loops, quite naturally define elements of the fundamental group of the billiard table. The simplest non-trivial fundamental group obtained this way belongs to the classical Sinai billiard, i.e. the billiard flow on the 2-torus with a single, strictly convex obstacle (with smooth boundary) removed. This fundamental group is known to be the group F 2 freely generated by two elements, which is a heavily noncommutative, hyperbolic group in Gromov’s sense. We define the homotopical rotation number and the homotopical rotation set for this model, and provide lower and upper estimates for the latter one, along with checking the validity of classically expected properties, like the density (in the homotopical rotation set) of the homotopical rotation numbers of periodic orbits.The natural habitat for these objects is the infinite cone erected upon the Cantor set Ends (F 2) of all ŋds" of the hyperbolic group F 2. An element of Ends (F 2) describes the direction in (the Cayley graph of) the group F 2 in which the considered trajectory escapes to infinity, whereas the height function t (t≧ 0) of the cone gives us the average speed at which this escape takes place.The main results of this paper claim that the orbits can only escape to infinity at a speed not exceeding \documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \usepackage{bbm} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $\sqrt 2$ \end{document}, and any direction e ∈ Ends (F 2) for the escape is feasible with any prescribed speed s, 0 ≦ s\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \usepackage{bbm} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $\sqrt 2$ \end{document}/2. This means that the radial upper and lower bounds for the rotation set R are actually pretty close to each other.

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Representability and amalgamation for Heyting polyadic algebras

Studia Scientiarum Mathematicarum Hungarica
Author: Tarek Ahmed

We prove that every (not necessarily locally finite) polyadic Heyting algebra of infinite dimension is representable in some concrete sense. We also show that this class has the super amalgamation property. As a byproduct we infer that a certain infinitary extension of predicate intuitionistic logic, or equivalently, the intuitionistic fragment of Keisler’s infinitary logics, is complete and enjoys the Craig interpolation property.

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The values of additive forms at prime arguments

Studia Scientiarum Mathematicarum Hungarica
Author: Haiwei Sun

Let E 2(V;X; δ) and E 4(V;X; δ) respectively denote the number of vV, vx such that the inequality \documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \usepackage{bbm} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $\left| {\lambda _1 p_1 + \lambda _2 p_2 ^2 - v} \right| < v^{ - \delta }$ \end{document} has no solution in primes p 1, p 2, and the number of vV, vx such that the inequality \documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \usepackage{bbm} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $\left| {\lambda _1 p_1 ^2 + \lambda _2 p_2 ^2 + \lambda _3 p_3 ^2 + \lambda _4 p_4 ^2 - v} \right| < v^{ - \delta }$ \end{document} has no solution in primes p 1, p 2, p 3, p 4. In both cases, we assume that all λ j are non-zero real numbers satisfying that λ 1/λ 2 is irrational and algebraic, and V is a well-spaced set. In this note we prove that \documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \usepackage{bbm} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $\begin{gathered} E_2 (\mathcal{V},X,\delta ) \ll X^{\tfrac{7}{8} + 2\delta + \varepsilon } , \hfill \\ E_4 (\mathcal{V},X,\delta ) \ll X^{\tfrac{3}{4} + 4\delta + \varepsilon } . \hfill \\ \end{gathered}$ \end{document}.

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A comparative study of interdisciplinary changes between information science and library science

Scientometrics
Authors: Mu-Hsuan Huang and Yu-Wei Chang

Abstract

This study employs the method of direct citation to analyze and compare the interdisciplinary characteristics of the two disciplines of library science and information science during the period of 1978–2007. Based on the research generated by five library science journals and five information science journals, library science researchers tend to cite publications from library and information science (LIS), education, business/management, sociology, and psychology, while researchers of information science tend to cite more publications from LIS, general science, computer science, technology, and medicine. This means that the disciplines with larger contributions to library science are almost entirely different from those contributing to information science. In addition, researchers of library science frequently cite publications from LIS; the rate is as high as 65.61%, which is much higher than the rate for information science, 49.50%. However, a decreasing trend in the percentage of LIS in library science indicates that library science researchers tend to cite more publications from non-LIS disciplines. A rising trend in the proportion of references to education sources is reported for library science articles, while a rising trend in the proportion of references to computer science sources has been found for information science articles. In addition, this study applies an interdisciplinary indicator, Brillouin's Index, to measurement of the degree of interdisciplinarity. The results confirm that the trend toward interdisciplinarity in both information science and library science has risen over the years, although the degree of interdisciplinarity in information science is higher than that in library science.

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Individual cognitive structures and collaboration patterns in academia

Scientometrics
Author: Bulent Ozel

Abstract

This article, elaborating on mutuality of knowledge and social structure theory borrowed from sociology of knowledge literature, where knowledge is perceived as an essentially social and societal category, develops a coherent research framework which relates cognitive structure and the collaboration patterns into an integrated socio-knowledge analysis of a given scientific community. The framework extends co-word analysis combining it with social network analysis. The framework is enhanced by introducing a novel model. The new model maps actors from co-authorship networks into a strategic diagram of scientists. The mapping is based on cohesiveness and pervasiveness of issues each author has published in the field. The exemplary longitudinal case from Turkey covers scientific publication activities in Turkish management academia spanning the years from 1922 until 2008. It is seen that, while within local community diffusion of management knowledge is lead by academicians with certain socio-cognitive properties, academicians publishing at international arena do not show any significantly differing socio-cognitive properties, instead, they are merely embedded in strongly connected groups. Leading academicians within local community, however, exhibit a common socio-cognitive structure relative to the rest of the community. They have more social ties and more diversified disseminated knowledge compared to the rest. Knowledge they disseminate is distinct compared to their peers in the network, they hold certain part of their knowledge exclusively, thus knowledge-wise they don't resemble the rest, but they keep a level of common knowledge with the rest of the community.

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The pathway of development: science and technology of NIEs and selected Asian emerging economies

Scientometrics
Authors: Chan-Yuan Wong and Kim-Leng Goh

Abstract

Many emerging countries in Asia demonstrate a strong pattern of growth and potential of diffusion in science and technology that is dynamic and self-propagating. To elucidate the evolution in science and technology and the institutional dynamics that drive the self-propagating behavior, this paper examines the divergent models pursued by selected Asian economies in regard to science and technological catch-up. An analysis of papers and patents production for each nation was conducted to examine the indigenous science and technology capabilities. This study focuses on six major economies, namely China, Malaysia, South Korea, Singapore, Taiwan and Thailand. In addition, Japan, a country with advanced development of science and technology, is included for comparison. The findings provided insight and understanding of evolving science and technological waves and the dynamic potentials in science and technology. We demonstrate the pursued catching-up models that drive the self-propagating behavior and industrialization, thus providing a more complete understanding of the innovation systems than those examined in previous studies.

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Research on the cross-citation relationship of core authors in scientometrics

Scientometrics
Authors: Feifei Wang, Junping Qiu and Houqiang Yu

Abstract

Generally speaking, citation relationship among authors can be divided into 3 types: co-citation, coupling and cross-citation. Since author co-citation analysis was first introduced in 1982, it has been widely applied to study discipline structure, research state and research trends. Afterwards, conception of author bibliographic-coupling analysis was put forward and related empirical studies provided a method for mapping active authors in a research field for a more realistic picture of the current state of its research activities. Additionally, if one of author A's papers has a citation from one of author B's, there is cross-citation relationship between A and B. However, studies based on author cross-citation relationship mainly describe citation behaviors themselves using citation identity and citation image; they rarely involve any implicit knowledge communication, author research correlation or discovering academic communities. Author cross-citation analysis infers to both citing and cited phenomenon, which can be roughly correspond to citation identity and citation image. The study will further explore the author cross-citation relationship with core authors in scientometrics field as study object in order to provide reference for development of scientometrics field and in-depth application of citation analysis.

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Research status and trends in limnology journals: a bibliometric analysis based on SCI database

Scientometrics
Authors: Xiaofeng Cao, Yi Huang, Jie Wang and Shengji Luan

Abstract

An effective bibliometric analysis was applied in this work to evaluate global scientific production of the subject category of “limnology” from 2001 to 2010. Data was based on the Science Citation Index compiled by Institute for Scientific Information (ISI), Philadelphia, USA. The h-index and NetDraw were designed to characterize the limnology publications. The results showed that the limnology research constantly increased over the past decade. The researchers paid most attention to “diatoms”, “eutrophication” and “phosphorus”. Moreover, the keywords plus of “growth”, “model”, “dynamic”, offered a thorough description for the limnology research. Among the research institutes interested in limnologic research, the US Geological Survey was the flagship while the USA attained a dominant position in the global research in the field.

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Visualization of research fronts and knowledge bases by three-dimensional areal densities of bibliographically coupled publications and co-citations

Scientometrics
Author: Edgar Schiebel

Abstract

In this work the well known scientometric concepts of bibliographically coupled publications and co-cited references were applied to produce interactive maps of research fronts and knowledge bases of research fields. This article proposes a method and some standardization for the detection and visualization of research fronts and knowledge bases with two and three dimensional graphics inspired by geographical maps. Agglomerations of bibliographically coupled publications with a common knowledge base are identified and graphically represented by a density function of publications per area unit. The research fronts become visible if publications with similar vectors of common citations are associated and visualized as an ensemble in a three dimensional graphical representation as a mountain scenery measured with the help of a spatial density. Knowledge bases were calculated in the same way. Maps similar to the geographic representation of oceans and islands are used to visualize the two-dimensional spatial density function of references weighted by individual links. The proposed methodology is demonstrated by publications in the field of battery research.

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A bibliometric study of earthquake research: 1900–2010

Scientometrics
Authors: Xingjian Liu, F. Benjamin Zhan, Song Hong, Beibei Niu and Yaolin Liu

Abstract

We evaluated earthquake research performance based on a bibliometric analysis of 84,051 documents published in journals and other outlets contained in the Scientific Citation Index (SCI) and Social Science Citation Index (SSCI) bibliographic databases for the period of 1900–2010. We summarized significant publication indicators in earthquake research, evaluated national and institutional research performance, and presented earthquake research development from a supplementary perspective. Research output descriptors suggested a solid development in earthquake research, in terms of increasing scientific production and research collaboration. We identified leading authors, institutions, and nations in earthquake research, and there was an uneven distribution of publications at authorial, institutional, and national levels. The most commonly used keywords appeared in the articles were evolution, California, deformation, model, inversion, seismicity, tectonics, crustal structure, fault, zone, lithosphere, and attenuation.

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Energy indicators and percentile ranking normalization

Scientometrics
Author: Gangan Prathap

Abstract

Scalar measures of research performance (Energy, Exergy, and Entropy or EEE) are based on what can be called the bibliometrics-thermodynamics consilience. Here, their application to the percentile ranking normalization scheme is demonstrated.

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Progressive nucleation mechanism for the growth behavior of items and its application to cumulative papers and citations of individual authors

Scientometrics
Author: Keshra Sangwal

Abstract

A general expression based on the concepts of the progressive nucleation mechanism is proposed in the form 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.

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Tendencies in scientific output on carbon nanotubes and graphene in global centers of excellence for nanotechnology

Scientometrics
Authors: Goio Etxebarria, Mikel Gomez-Uranga and Jon Barrutia

Abstract

A change has been taking place in the world of nanotechnologies since 2009, marking the beginning of a new era of end consumer goods related to these new technologies. In this article, our aim is to know the dominant tendencies observed in scientific output on carbon nanotubes at centres and poles from different countries and considered to be at the forefront of nanotechnologies research. We have selected a sample comprised of eight universities and locally coherent concentrations from different geographic areas: Europe, America and Asia. Based on this sample, we have used the Scopus database to analyse scientific output on carbon nanotubes in order to determine if there are significant differences in behaviour. We observe that dynamics of scientific output on nanotubes are similar in the universities and clusters analysed over time although a drop in publications was noted in 2009 in part of the organizations included in the sample. We have seen a large amount of publications on graphene in the last several years, due to the fact that researchers working in the field of carbon nanotubes gradually move towards the study of graphene, explained by the high expectations concerning the use of this element. The results lead us to conclude that advances in knowledge on carbon nanotubes and graphene will make it possible to meet the growing needs of a new and powerful market for products that are progressively including these new elements.

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Alone or together: examples from history research

Scientometrics
Author: Ülle Must

Abstract

Individualistic nature of research in the humanities is a common fact, as well as the notion that boundaries in humanities are poorly defined. Using citation analysis we have to take into account differences in citation practices not only between humanities and sciences but also within narrower fields of humanities. In the current study we observe differences between publication behaviour of historians and archaeologists, examine some aspects of citation practices in those fields, and show their effect on visibility.

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‘Cognitive mobility’ or migration of authors between fields used in mapping a network of mathematics

Scientometrics
Authors: Aparna Basu and Roland Wagner Dobler

Abstract

In this paper we have looked at a new measure of connectedness between research areas, namely, the migration of authors between subfields as seen from their contributions to different areas. Migration may be considered as an embodied knowledge flow that bridges some part of the cognitive gap between fields. Our hypothesis is that the rate of author migration will reflect cognitive similarity or affinity between disciplines. This is graphically shown to be reasonable, but only above certain levels of migration for our data from mathematical reviews spanning 17 years (1959–1975). The inter-related structure of Mathematics is then mapped using migration data in the appropriate range. We find the resulting map to be a good reflection of the disciplinary variation in the field of Mathematics.

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Comprehensive bibliographic coverage of the social sciences and humanities in a citation index: an empirical analysis of the potential

Scientometrics
Authors: Gunnar Sivertsen and Birger Larsen

Abstract

A well-designed and comprehensive citation index for the social sciences and humanities has many potential uses, but has yet to be realised. Significant parts of the scholarly production in these areas are not published in international journals, but in national scholarly journals, in book chapters or in monographs. The potential for covering these literatures more comprehensively can now be investigated empirically using a complete publication output data set from the higher education sector of an entire country (Norway). We find that while the international journals in the social sciences and humanities are rather small and more dispersed in specialties, representing a large but not unlimited number of outlets, the domestic journal publishing, as well as book publishing on both the international and domestic levels, show a concentration of many publications in few publication channels. These findings are promising for a more comprehensive coverage of the social sciences and humanities.

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A study of scientometric methods to identify emerging technologies via modeling of milestones

Scientometrics
Authors: Robert K. Abercrombie, Akaninyene W. Udoeyop and Bob G. Schlicher

Abstract

This work examines a scientometric model that tracks the emergence of an identified technology from initial discovery (via original scientific and conference literature), through critical discoveries (via original scientific, conference literature and patents), transitioning through Technology Readiness Levels (TRLs) and ultimately on to commercial application. During the period of innovation and technology transfer, the impact of scholarly works, patents and on-line web news sources are identified. As trends develop, currency of citations, collaboration indicators, and on-line news patterns are identified. The combinations of four distinct and separate searchable on-line networked sources (i.e., scholarly publications and citation, patents, news archives, and on-line mapping networks) are assembled to become one collective network (a dataset for analysis of relations). This established network becomes the basis from which to quickly analyze the temporal flow of activity (searchable events) for the example subject domain we investigated.

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The development trends of science in the CIS countries on the basis of some scientometric indicators

Scientometrics
Author: Renat Karamourzov

Abstract

The article attempts to assess the results of the independent development of the CIS countries in the field of science over the period 1990–2009. The analysis of the numerous scientometric indicators reveals the decrease of the number of expert researchers and the significant decrease in the scientific and technical output. The article also provides the information about the dynamics of a set of indicators which allows to draw conclusions about the effectiveness of the research activity in the CIS countries.

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The 13th International Conference on Scientometrics and Informetrics

Scientometrics
Authors: Dennis Ocholla, Peter Ingwersen, Ed C.M. Noyons and Wolfgang Glänzel
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Comments on “a bibliometric study of the trend in articles related to eutrophication published in Science Citation Index”

Scientometrics
Authors: Kun-Yang Chuang and Yuh-Shan Ho
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Research performance and collaboration in the Novosibirsk region

Scientometrics
Authors: V. A. Markusova, A. N. Libkind, A. E. Varshavsly and C. N. M. Jansz

Abstract

The Novosibirsk region is one of the most industrialized in Siberia. In 1957 the Siberian Branch of the Academy of Sciences of the USSR (now Siberian Branch of the RAS (SBRAS)) was set up to stimulate a rapid development of the Siberian and Far East research forces. The goal of this mainly bibliometric, empirical study is to obtain insight into R&D performance in the Novosibirsk region, domestic and international collaborations and the impact of new government science policies focused on boosting the research and innovation activities of regional universities. Key drivers of research performance are institutions of the SBRAS. Second place in terms of research output belongs to Novosibirsk State University. Its research focuses on hard sciences. 75% of its papers were published in collaboration with SBRAS institutions. Research output is growing. Novosibirsk area's share of RFBR grants was stable around 8%. Publications from RFBR grantees in 34 subject categories had a level-aggregated indicator value of one or higher. In these hard-science areas Russian research develops in accordance with global trends. We observed a concentration of domestic collaboration in the Novosibirsk area as well as a strong international collaboration with advanced economies, in particular in the Asia–Pacific region.

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Authors’ sources of information: a new dimension in information scattering

Scientometrics
Authors: Zahed Bigdeli and Ali Gazni

Abstract

The purpose of this study is to determine the usage patterns of core journals by scholars, and to address the differences among various academic disciplines. Thus, the references of 11,230 corresponding authors for the past 35 years from the world's top five highly cited universities and institutions were analyzed. To build robust models of information scattering, we need a deeper understanding of this phenomenon. The results show that core journals usage is a social phenomenon, in exactly the same way as Bradford's law, Zipf's law and Lotka's law. The analysis of author references shows that if core scientific journals are arranged in order of decreasing productivity, then they could be divided into a small group of highly cited periodicals and a large group of minimally cited ones. Scholars may do browsing and similar information-seeking activities to form their core journals, and the findings may support Bates's hypothesis that Bradford's core zone is best searched by browsing. Bradford's law and relevant research may consequently help to solve many of the practical problems that practitioners of the profession face, particularly in collection development in libraries, and help users to gather highly scattered information.

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Collaboration network patterns and research performance: the case of Korean public research institutions

Scientometrics
Authors: Duk Hee Lee, Il Won Seo, Ho Chull Choe and Hee Dae Kim

Abstract

This study examines the impact of collaborating patterns on the R&D performance of public research institutions (PRIs) in Korea's science and engineering fields. For the construction of R&D collaborating networks based on the co-authorship data of 127 institutions in Scopus, this paper proposes four types of collaborations by categorizing network analyses into two dimensions: structural positions (density, efficiency, and betweeness centrality) and the relational characteristics of individual nodes (eigenvector and closeness centralities). To explore the research performance by collaboration type, we employ a data envelopment analysis window analysis of a panel of 23 PRIs over a 10-year period. Comparing the R&D productivities of each group, we find that the PRIs of higher productivity adhere to a cohesive networking strategy, retaining intensive relations with their existing partners. The empirical results suggest that excessively cohesive alliances might end up in ‘lock-in’ relations, hindering the exploitation of new opportunities for innovation. These findings are implicit in relation to the Korean Government's R&D policies on collaborating strategies to produce sustained research results with the advent of the convergence research era.

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ASEAN benchmarking in terms of science, technology, and innovation from 1999 to 2009

Scientometrics
Authors: V. Rodriguez and A. Soeparwata

Abstract

This article provides an empirical assessment of the performance of the member states of the Association of Southeast Asian Nations in terms of science, technology, and innovation. This study is relevant because it employs a larger data set, examines more countries, and covers more years than previous studies. The results indicate that these countries had differing patterns of performance, and the pattern of growth among them was asymmetrical. Additional findings suggest that these countries performed idiosyncratically with respect to the six quantitative dimensions we examined. Our research includes a form of comparative policy evaluation that might assist the monitoring of the implementation of “Vision 2020”. The results simplify how we determine the relative strengths and weaknesses of national innovation systems and are relevant to policy discussions. In relation to transferability, the findings demonstrate similarities to the European Union with regard to performance and governance.

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Comments on “A Hirsch-type index of co-author partnership ability”

Scientometrics
Author: Ronald Rousseau
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South African universities in world rankings

Scientometrics
Author: Alan Peter Matthews

Abstract

South Africa has 23 universities, of which five are placed in one or more of the 2011 Shanghai Jiao Tong, Times Higher Education, and Quacquarelli Symonds world university rankings. The five are: Cape Town, Witwatersrand, KwaZulu-Natal, Stellenbosch and Pretoria. They are ranked above the other 18 universities, with Cape Town in top position, mainly because they have significantly higher publication and citation counts. In the Shanghai Jiao Tong ranking Cape Town's Nobel Prize alumni and highly-cited researchers give it an additional lead over second-placed Witwatersrand, which has Nobel Prize alumni but no highly-cited researchers. KwaZulu-Natal, in third place, has no Nobel Prize alumni but one highly-cited researcher, which places it ahead of Stellenbosch and Pretoria despite the latter two having higher publication output. However, in the Times Higher Education ranking, which places Cape Town first and Witwatersrand second, Stellenbosch is ranked but not KwaZulu-Natal, presumably because the publication and citation counts of Stellenbosch are higher. The other 18 universities are ranked by the SCImago and Webometrics rankings in an order consistent with bibliometric indicators, and consistent with approximate simulations of the Shanghai Jiao Tong and Times Higher Education methods. If a South African university aspires to rise in the rankings, it needs to increase publications, citations, staff-student ratio, and proportions of postgraduate students, international students and international staff.

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Finite groups with sn-embedded or s-embedded subgroups

Acta Mathematica Hungarica
Author: Izabela Agata Malinowska

Abstract

A number of authors have studied the structure of a finite group G under the assumption that some subgroups of G are well located in G. We will generalize the notion of s-permutable and s-permutably embedded subgroups and we will obtain new criterions of p-nilpotency and supersolvability of groups. We also generalize some known results.

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On relations between γ-operations

Acta Mathematica Hungarica
Author: Won Keun Min

Abstract

Let expX be the power set of a non-empty set X. A function γ: expX→expX is said to be monotonic iff ABX implies γAγB. Császár [2] investigated relations between the monotonic functions. The purpose of the paper is to investigate some results concerning particular monotonic functions.

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On the sum of a prime and a k-th power of prime in short intervals

Acta Mathematica Hungarica
Author: Y. C. Wang

Abstract

Let denote the set {n∣2|n, ∀ p>2 with p−1|k}. We prove that when , almost all integers can be represented as the sum of a prime and a k-th power of prime for k≧3. Moreover, when , almost all integers n∊(X,X+H] can be represented as the sum of a prime and a k-th power of integer for k≧3.

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Remark on the completeness of an exponential type sequence

Acta Mathematica Hungarica
Authors: Yong-Gao Chen and Jin-Hui Fang

Abstract

B. J. Birch [1] proved that all sufficiently large integers can be expressed as a sum of pairwise distinct terms of the form p a q b, where p, q are given coprime integers greater than 1. Subsequently, Davenport pointed out that the exponent b can be bounded in terms of p and q. N. Hegyvári [3] gave an effective version of this bound. In this paper, we improve this bound by reducing one step.

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Remarks on generalized hyperconnectedness

Acta Mathematica Hungarica

Abstract

The main aim of this paper is to show that every GTS can be realized as a μ-closed subspace of a generalized hyperconnected space. Also, we give more characterizations of generalized hyperconnected spaces.

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Self-intersections of immersions and Steenrod operations

Acta Mathematica Hungarica
Authors: Peter J. Eccles and Mark Grant

Abstract

We present a formula describing the action of a generalised Steenrod operation of ℤ2-type [14] on the cohomology class represented by a proper self-transverse immersion f: MX. Our formula depends only on the Umkehr map, the characteristic classes of the normal bundle, and the class represented by the double point immersion of f. This generalises a classical result of R. Thom [13]: If αH k(X;ℤ2) is the ordinary cohomology class represented by f: MX, then Sq i(α)=f w i(ν f).

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Citation genetic genealogy: a novel insight for citation analysis in scientific literature

Scientometrics
Authors: Fengjun Sun and Lijun Zhu

Abstract

Citation relationships are commonly described with citation network or citation graph, but in this article, the author introduced the notion of citation genetic genealogy and apply it in citation analysis. A citing document usually only uses pieces of its cited document, so the author of this article defined these valuable pieces of a scientific document, which carry the information that have been used by its citing documents as its document genes. Besides, with the definition of symbolic information of a scientific document, the conclusion that a citing document inherited the document genes from its references can be drawn. Based on these understandings, citation genetic genealogy is constructed to describe citation relationships. With citation genetic genealogy, it is easy to map the citation relationships, like bibliographic coupling and co-citation, with familiar family relationships and illustrate the inheritance relationships in scientific literatures. Also, citation genetic genealogy may provide an interface between the citation analysis of a document set and the content analysis for each individual document inside this document set.

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Identifying the global core-periphery structure of science

Scientometrics
Author: Ryan Zelnio

Abstract

While there is a consensus that there is a core-periphery structure in the global scientific enterprise, there have not been many methodologies developed for identifying this structure. This paper develops a methodology by looking at the differences in the power law structure of article outputs and degree centrality distributions of countries. This methodology is applied to five different scientific fields: astronomy and astrophysics, energy and fuels, nanotechnology and nanosciences, nutrition, and oceanography. This methodology uncovers a two-tiered power law structure that exists in all examined fields. The core-periphery structure that is unique to each field is characterized by the core's size, minimum degree, and exponent of its power law distribution. Stark differences are identified between technology and non-technology intensive scientific fields.

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The impact factor: its place in Garfield's thought, in science evaluation, and in library collection management

Scientometrics
Author: Stephen J. Bensman

Abstract

This paper is a response to that of Vanclay, who proposes, that since the impact factor (IF) is so seriously flawed, Thomson Reuters should either correct the measure or—preferably—no longer publish it and restrict itself to journal certification. It is argued here that Vanclay's analysis is itself seriously flawed, because he appears totally ignorant of the thought structure of Eugene Garfield, IF's creator. As a result, Vanclay appears unaware of the importance of total cites and the close connection of IF with review journals, where the paradigms of science are defined. This paper's author agrees that IF is a defective measure, analyzing its defects from the perspective of the frequency theory of probability, on which modern inferential statistics is based. However, he asserts that abandoning it would be counterproductive because of its demonstrated ability—even with its defects—to identify small important journals like review journals, giving it an important role in science evaluation and library collection management.

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Mapping technological innovations through patent analysis: a case study of foreign multinationals and indigenous firms in China

Scientometrics
Authors: Chan-Yuan Wong and Xiao-Shan Yap

Abstract

This study attempts to expand the work on patenting activities of China. The characteristics of foreign multinationals and indigenous entities’ patenting activities in the US patent system are examined in our analysis. This study also attempts to model the diffusion trajectories of patenting activities that result from the functioning of two competing innovation system models adopted by China-FDI and indigenous—to compare the extent of divergence of technological innovations. The findings are useful for highlighting the path of technological innovations and understanding the dynamic potentials through analysis of the growth process. While the results suggest a dominance of foreign firms in patenting activities since the early 2000s, there is a sign of transition from industrial-based to knowledge-driven activities and the formation of evolving propagating behaviour in the production of indigenous technology.

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Structural indicators in citation networks

Scientometrics
Authors: Xiaojun Hu, Ronald Rousseau and Jin Chen

Abstract

New indicators, including the outgrow index, characterizing an article in its ego citation network are introduced. We take full advantage of the existing duality (cites–is cited by) in a citation network. Although algebraic aspects are emphasized, a first step towards their interpretation is attempted. Examples of their calculation and of future applications are provided.

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Analysis of the relationship between citation frequency of patents and diversity of their backward citations for Japanese patents

Scientometrics
Authors: Fuyuki Yoshikane, Yutaka Suzuki and Keita Tsuji

Abstract

Conventional patent citation analyses have focused mainly on the presence of citation relationships, the number of patents cited by the subject patent, and the number of times the subject patent is cited by others (i.e., the numbers of backward and forward citations of the subject patent). However, most of them have not focused on patent classifications. Assuming that a patent based on a variety of technological bases tends to be an important patent that is cited more often, this study examines and clarifies the relationship between the diversity of classifications assigned to backward citations and the number of forward citations for Japanese patents. The results show notable differences in the number of classifications assigned to backward citations between the often cited and less frequently cited groups. It is considered that the diversity of backward citations can be utilized in the evaluation criteria for grouping that roughly identifies the often cited patents or eliminates a large part of less frequently cited patents.

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Author disambiguation using multi-aspect similarity indicators

Scientometrics
Authors: Thomas Gurney, Edwin Horlings and Peter van den Besselaar

Abstract

Key to accurate bibliometric analyses is the ability to correctly link individuals to their corpus of work, with an optimal balance between precision and recall. We have developed an algorithm that does this disambiguation task with a very high recall and precision. The method addresses the issues of discarded records due to null data fields and their resultant effect on recall, precision and F-measure results. We have implemented a dynamic approach to similarity calculations based on all available data fields. We have also included differences in author contribution and age difference between publications, both of which have meaningful effects on overall similarity measurements, resulting in significantly higher recall and precision of returned records. The results are presented from a test dataset of heterogeneous catalysis publications. Results demonstrate significantly high average F-measure scores and substantial improvements on previous and stand-alone techniques.

Open access

An impact-citations-exergy (iCX) trajectory analysis of leading research institutions in India

Scientometrics
Authors: P. Nishy, Yatish Panwar, Suresh Prasad, G. K. Mandal and Gangan Prathap

Abstract

A thermodynamic analogy allows bibliometric research assessment of information production processes to be based on a scalar indicator which is an energy-like term called exergy. Derived from standard indicators like impact, citations and number of papers, the exergy indicator X is a multiplicative product of quality and quantity of a scientist's or group's performance using available bibliometric information. Thus, given the bibliometric sequences of leading research agencies and institutions, research performance can be displayed as trajectories on a two-dimensional map as time progresses. In this paper, we track the performance of several of the leading players contributing to academic scientific research in India.

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A co-word analysis of digital library field in China

Scientometrics
Authors: Gao-Yong Liu, Ji-Ming Hu and Hui-Ling Wang

Abstract

The aim of this study is to map the intellectual structure of digital library (DL) field in China during the period of 2002–2011. Co-word analysis was employed to reveal the patterns of DL field in China through measuring the association strength of keywords in relevant journals. Data was collected from Chinese Journal Full-Text Database during the period of 2002–2011. And then, the co-occurrence matrix of keywords was analyzed by the methods of multivariate statistical analysis and social network analysis. The results mainly include five parts: seven clusters of keywords, a two-dimensional map, the density and centrality of clusters, a strategic diagram, and a relation network. The results show that there are some hot research topics and marginal topics in DL field in China, but the research topics are relatively decentralized compared with the international studies.

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Mapping interactions within the evolving science of science and innovation policy community

Scientometrics
Authors: Angela M. Zoss and Katy Börner

Abstract

The Science of Science and Innovation Policy (SciSIP) program at the National Science Foundation (NSF) supports research designed to advance the scientific basis of science and innovation policy. The program was established at NSF in 2005 in response to a call from Dr. John Marburger III, then science advisor to the U.S. President, for a “science” of science policy. As of January 2011, it has co-funded 162 awards that aim to develop, improve, and expand data, analytical tools, and models that can be directly applied in the science policy decision making process. The long-term goals of the SciSIP program are to provide a scientifically rigorous and quantitative basis for science policy and to establish an international community of practice. The program has an active listserv that, as of January 2011, has almost 700 members from academia, government, and industry. This study analyzed all SciSIP awards (through January 2011) to identify existing collaboration networks and co-funding relations between SciSIP and other areas of science. In addition, listserv data was downloaded and analyzed to derive complementary discourse information. Key results include evidence of rich diversity in communication and funding networks and effective strategies for interlinking researcher and science policy makers, prompting discussion, and resource sharing.

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Scientometrics