117,195 research outputs found

    Microwave integrated circuit for Josephson voltage standards

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    A microwave integrated circuit comprised of one or more Josephson junctions and short sections of microstrip or stripline transmission line is fabricated from thin layers of superconducting metal on a dielectric substrate. The short sections of transmission are combined to form the elements of the circuit and particularly, two microwave resonators. The Josephson junctions are located between the resonators and the impedance of the Josephson junctions forms part of the circuitry that couples the two resonators. The microwave integrated circuit has an application in Josephson voltage standards. In this application, the device is asymmetrically driven at a selected frequency (approximately equal to the resonance frequency of the resonators), and a d.c. bias is applied to the junction. By observing the current voltage characteristic of the junction, a precise voltage, proportional to the frequency of the microwave drive signal, is obtained

    Acyclic orientations on the Sierpinski gasket

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    We study the number of acyclic orientations on the generalized two-dimensional Sierpinski gasket SG2,b(n)SG_{2,b}(n) at stage nn with bb equal to two and three, and determine the asymptotic behaviors. We also derive upper bounds for the asymptotic growth constants for SG2,bSG_{2,b} and dd-dimensional Sierpinski gasket SGdSG_d.Comment: 20 pages, 8 figures and 6 table

    Exposing the dressed quark's mass

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    This snapshot of recent progress in hadron physics made in connection with QCD's Dyson-Schwinger equations includes: a perspective on confinement and dynamical chiral symmetry breaking (DCSB); a pre'cis on the physics of in-hadron condensates; results on the hadron spectrum, including dressed-quark-core masses for the nucleon and Delta, their first radial excitations, and the parity-partners of these states; an illustration of the impact of DCSB on the electromagnetic pion form factor, thereby exemplifying how data can be used to chart the momentum-dependence of the dressed-quark mass function; and a prediction that F_1^{p,d}/F_1^{p,u} passes through zero at Q^2\approx 5m_N^2 owing to the presence of nonpointlike scalar and axial-vector diquark correlations in the nucleon.Comment: 10 pages, 4 figures, 2 tables. Contribution to the Proceedings of the 4th Workshop on Exclusive Reactions at High Momentum Transfer, Thomas Jefferson National Accelerator Facility Newport News, Virginia, 18-21 May 201

    What do Experts Know About Ranking Journal Quality? A Comparison with ISI Research Impact in Finance

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    Experts possess knowledge and information that are not publicly available. The paper is concerned with the ranking of academic journal quality and research impact using a survey of experts from a national project on ranking academic finance journals. A comparison is made with publicly available bibliometric data, namely the Thomson Reuters ISI Web of Science citations database (hereafter ISI) for the Business - Finance category. The paper analyses the leading international journals in Finance using expert scores and quantifiable Research Assessment Measures (RAMs), and highlights the similarities and differences in the expert scores and alternative RAMs, where the RAMs are based on alternative transformations of citations taken from the ISI database. Alternative RAMs may be calculated annually or updated daily to answer the perennial questions as to When, Where and How (frequently) published papers are cited (see Chang et al. (2011a, b, c)). The RAMs include the most widely used RAM, namely the classic 2-year impact factor including journal self citations (2YIF), 2-year impact factor excluding journal self citations (2YIF*), 5-year impact factor including journal self citations (5YIF), Immediacy (or zero-year impact factor (0YIF)), Eigenfactor, Article Influence, C3PO (Citation Performance Per Paper Online), h-index, PI-BETA (Papers Ignored - By Even The Authors), 2-year Self-citation Threshold Approval Ratings (2Y-STAR), Historical Self-citation Threshold Approval Ratings (H-STAR), Impact Factor Inflation (IFI), and Cited Article Influence (CAI). As data are not available for 5YIF, Article Influence and CAI for 13 of the leading 34 journals considered, 10 RAMs are analysed for 21 highly-cited journals in Finance. Harmonic mean rankings of the 10 RAMs for the 34 highly-cited journals are also presented. It is shown that emphasizing the 2-year impact factor of a journal, which partly answers the question as to When published papers are cited, to the exclusion of other informative RAMs, which answer Where and How (frequently) published papers are cited, can lead to a distorted evaluation of journal impact and influence relative to the Harmonic Mean rankings. A simple regression model is used to predict expert scores on the basis of RAMs that capture journal impact, journal policy, the number of high quality papers, and quantitative information about a journal.IFI;PI-BETA;STAR;article influence;eigenfactor;h-index;C3PO;impact factor;research assessment measures;C81;C83;C18;expert scores;journal quality

    Daily Tourist Arrivals, Exchange Rates and Volatility for Korea and Taiwan

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    Both domestic and international tourism are a major source of service export receipts for many countries worldwide, and is also increasingly important in Taiwan. One of the three leading tourism source countries for Taiwan is the Republic of Korea, which is a source of short haul tourism. Daily data from 1 January 1990 to 31 December 2008 are used to model the Korean Won / New Taiwan exchangerateandtouristarrivalsfromKoreatoTaiwan,aswellastheirassociatedvolatility.ThesampleperiodincludestheAsianeconomicandfinancialcrisesin1997,andasignificantpartoftheglobalfinancialcrisisof200809.InclusionoftheexchangerateallowsapproximatedailypriceeffectsonKoreantourismarrivalstoTaiwantobecaptured.TheHeterogeneousAutoregressive(HAR)modelisusedtocapturelongmemorypropertiesinexchangeratesandKoreantouristarrivals,totestwhetheralternativeestimatesofconditionalvolatilityaresensitivetothelongmemoryintheconditionalmean,andtoexamineasymmetryandleverageinvolatility.Theempiricalresultsshowthattheconditionalvolatilityestimatesarenotsensitivetothelongmemorynatureoftheconditionalmeanspecifications.TheQMLEfortheGARCH(1,1),GJR(1,1)andEGARCH(1,1)modelsforKoreantouristarrivalstoTaiwanandtheKoreanWon/NewTaiwan exchange rate and tourist arrivals from Korea to Taiwan, as well as their associated volatility. The sample period includes the Asian economic and financial crises in 1997, and a significant part of the global financial crisis of 2008-09. Inclusion of the exchange rate allows approximate daily price effects on Korean tourism arrivals to Taiwan to be captured. The Heterogeneous Autoregressive (HAR) model is used to capture long memory properties in exchange rates and Korean tourist arrivals, to test whether alternative estimates of conditional volatility are sensitive to the long memory in the conditional mean, and to examine asymmetry and leverage in volatility. The empirical results show that the conditional volatility estimates are not sensitive to the long memory nature of the conditional mean specifications. The QMLE for the GARCH(1,1), GJR(1,1) and EGARCH(1,1) models for Korean tourist arrivals to Taiwan and the Korean Won / New Taiwan exchange rate are statistically adequate and have sensible interpretations. Asymmetry (though not leverage) is found for several alternative HAR models.exchange rates;GARCH;leverage;asymmetry;long memory;EGARCH;HAR;Korean tourist arrivals;GJR;global financial crisis;approximate price effect

    How are Journal Impact, Prestige and Article Influence Related? An Application to Neuroscience

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    The paper analyses the leading journals in Neurosciences using quantifiable Research Assessment Measures (RAM), highlights the similarities and differences in alternative RAM, shows that several RAM capture similar performance characteristics of highly cited journals, and shows that some other RAM have low correlations with each other, and hence add significant informational value. Alternative RAM are discussed for the Thomson Reuters ISI Web of Science database (hereafter ISI). The RAM that are calculated annually or updated daily include the classic 2-year impact factor (2YIF), 5-year impact factor (5YIF), Immediacy (or zero-year impact factor (0YIF)), Eigenfactor score, Article Influence score, C3PO (Citation Performance Per Paper Online), h-index, Zinfluence, PI-BETA (Papers Ignored - By Even The Authors), 2-year and historical Self-citation Threshold Approval Ratings (STAR), Impact Factor Inflation (IFI), and Cited Article Influence (CAI). The RAM are analysed for 26 highly cited journals in the ISI category of Neurosciences. The paper finds that the Eigenfactor score and PI-BETA are not highly correlated with the other RAM scores, so that they convey additional information regarding journal rankings, that Article Influence is highly correlated with some existing RAM, so that it has little informative incremental value, and that CAI has additional informational value to that of Article Influence. Harmonic mean rankings of the 13 RAM criteria for the 26 highly cited journals are also presented. Emphasizing the 2-year impact factor of a journal to the exclusion of other informative RAM criteria is shown to lead to a distorted evaluation of journal performance and influence, especially given the informative value of several other RAM.prestige;IFI;PI-BETA;STAR;eigenfactor;h-index;immediacy;zinfluence;C3PO;impact factor;article Influence;cited article influence

    What Makes a Great Journal Great in Economics? The Singer Not the Song.

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    The paper is concerned with analysing what makes a great journal great in economics, based on quantifiable measures. Alternative Research Assessment Measures (RAM) are discussed, with an emphasis on the Thomson Reuters ISI Web of Science database (hereafter ISI). The various ISI RAM that are calculated annually or updated daily are defined and analysed, including the classic 2-year impact factor (2YIF), 5-year impact factor (5YIF), Immediacy (or zero-year impact factor (0YIF)), Eigenfactor score, Article Influence, C3PO (Citation Performance Per Paper Online), h-index, Zinfluence, PI-BETA (Papers Ignored - By Even The Authors), and two new RAM measure, the Self-citation Threshold Approval Rating (STAR) score and the Impact Factor Inflation (IFI) score. The ISI RAM data are analysed for the most highly cited journals in the ISI categories of Economics, Management, Business, and Business - Finance. The journals are chosen on the basis of 2YIF (including self citations by both author and journal). The application to these four ISI categories could be used as a template for other ISI categories in both the Social Sciences and the Sciences, and as a benchmark for newer journals in a range of ISI disciplines. In addition to evaluating high quality research in the most highly cited Economics journals, the paper also compares the most highly cited journals in Management, Business, and Business - Finance, alternative RAM, highlights the similarities and differences in alternative RAM criteria, finds that several ISI RAM capture similar performance characteristics for the most highly cited Economics, Management, Business and Business - Finance journals, determines that the Immediacy and PI-BETA scores are not highly correlated with the other ISI RAM, and hence conveys additional information regarding ISI RAM criteria. Harmonic mean rankings of the 12 RAM criteria for the most highly cited journals in the four categories are also presented. It was shown that emphasizing THE impact factor, specifically the 2-year impact factor, of a journal to the exclusion of other useful and illuminating RAM criteria, can lead to a distorted evaluation of journal performance and influence on the profession.IFI;PI-BETA;STAR;article influence;eigenfactor;h-index;immediacy;impact factors;measures;research assessment;zinfluence;C3PO

    Least-squares finite elements for Stokes problem

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    A least-squares method based on the first-order velocity-pressure-vorticity formulation for the Stokes problem is proposed. This method leads to a minimization problem rather than to a saddle-point problem. The choice of the combinations of elements is thus not subject to the Ladyzhenskaya-Babuska-Brezzi (LBB) condition. Numerical results are given for the optimal rate of convergence for equal-order interpolations
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