108 research outputs found

    Manual Evaluation of Robot Performance in Identifying Open Access Articles

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    Antelman et al. (2005) hand-tested the accuracy of the algorithm that Hajjem et al.'s (2005) software robot used to trawl the web and automatically identify Open Access (OA) and Non-Open-Access (NOA) articles (references derived from the ISI database). Antelman et al. found much lower accuracy than Hajjem et al. Had reported. Hajjem et al. have now re-done the hand-testing on a larger sample (1000) in Biology, and demonstrated that Hajjem et al.'s original estimate of the robot's accuracy was much closer to the correct one. The discrepancy was because both Antelman et al. And Hajjem et al had hand-checked a sample other than the one the robot was sampling. Our present sample, identical with what the robot saw, yielded: d' 2.62, bias 0.68, true OA 93%, false OA 12%. We also checked whether the OA citation advantage (the ratio of the average citation counts for OA articles to the average citation counts for NOA articles in the same journal/issue) was an artifact of false OA: The robot-based OA citation Advantage of OA over NOA for this sample [(OA-NOA)/NOA x 100] was 70%. We partitioned this into the ratio of the citation counts for true (93%) OA articles to the NOA articles versus the ratio of the citation counts for the false (12%) "OA" articles. The "false OA" advantage for this 12% of the articles was 33%, so there is definitely a false OA Advantage bias component in our results. However, the true OA advantage, for 93% of the articles, was 77%. So in fact, we are underestimating the true OA advantage

    Complementarities between organizational changes, R&D activity and technological cooperation for the French manufacturing firms

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    This article analyzes the determinants of the French companies’ innovation activity while highlighting the importance and the complementarities of the organizational and technological practices’impact. Our results suggest on one hand, that the product or process innovation is determined by the internal and external attributes of the company (size, demand pull and technological class). On the other hand, the complementarities tests between the technological (R&D activity and technological partnership) and organizational practices showed that these strategies are interconnected and that they have complementary effects which call for their simultaneous adoption. Accordingly, to be able to benefit completely from the positive effect of the partnership and the R&D efforts on innovation, they must be accompanied by certain organizational practices related to a good skills management and the implementation of an organizational architecture facilitating the knowledge creation and sharing.innovation, complementarities, technological and organizational competencies

    Self-selected or mandated, open access increases citation impact for higher quality research

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    Articles whose authors make them Open Access (OA) by self-archiving them online are cited significantly more than articles accessible only to subscribers. Some have suggested that this "OA Advantage" may not be causal but just a self-selection bias, because authors preferentially make higher-quality articles OA. To test this we compared self-selective self-archiving with mandatory self-archiving for a sample of 27,197 articles published 2002-2006 in 1,984 journals. The OA Advantage proved just as high for both. Logistic regression showed that the advantage is independent of other correlates of citations (article age; journal impact factor; number of co-authors, references or pages; field; article type; country or institution) and greatest for the most highly cited articles. The OA Advantage is real, independent and causal, but skewed. Its size is indeed correlated with quality, just as citations themselves are (the top 20% of articles receive about 80% of all citations). The advantage is greater for the more citeable articles, not because of a quality bias from authors self-selecting what to make OA, but because of a quality advantage, from users self-selecting what to use and cite, freed by OA from the constraints of selective accessibility to subscribers only. [See accompanying RTF file for responses to feedback. Four PDF files provide Supplementary Analysis.

    Ten-Year Cross-Disciplinary Comparison of the Growth of Open Access and How it Increases Research Citation Impact

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    Lawrence (2001)found computer science articles that were openly accessible (OA) on the Web were cited more. We replicated this in physics. We tested 1,307,038 articles published across 12 years (1992-2003) in 10 disciplines (Biology, Psychology, Sociology, Health, Political Science, Economics, Education, Law, Business, Management). A robot trawls the Web for full-texts using reference metadata ISI citation data (signal detectability d'=2.45; bias = 0.52). Percentage OA (relative to total OA + NOA) articles varies from 5%-16% (depending on discipline, year and country) and is slowly climbing annually (correlation r=.76, sample size N=12, probability p < 0.005). Comparing OA and NOA articles in the same journal/year, OA articles have consistently more citations, the advantage varying from 36%-172% by discipline and year. Comparing articles within six citation ranges (0, 1, 2-3, 4-7, 8-15, 16+ citations), the annual percentage of OA articles is growing significantly faster than NOA within every citation range (r > .90, N=12, p < .0005) and the effect is greater with the more highly cited articles (r = .98, N=6, p < .005). Causality cannot be determined from these data, but our prior finding of a similar pattern in physics, where percent OA is much higher (and even approaches 100% in some subfields), makes it unlikely that the OA citation advantage is merely or mostly a self-selection bias (for making only one's better articles OA). Further research will analyze the effect's timing, causal components and relation to other variables.Comment: 10 pages, 5 figures, 3 table

    Repositories for Institutional Open Access: Mandated Deposit Policies

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    Only 15% of articles are currently being made Open Access (OA) through spontaneous self-archiving efforts by their authors. They average 25%-250% more citations in all 12 disciplines tested so far. Ninety-four percent of journals endorse immediate OA self-archiving. There is no evidence that self-archiving induces subscription cancellations. The “OA advantage” consists of: Early Advantage (early self-archiving produces both earlier and more citations), Usage Advantage (more downloads for OA articles, correlated with later citations), Competitive Advantage (relative citation advantage of OA over non-OA articles: disappears at 100% OA), Quality Advantage (OA advantage is higher, the higher the quality of the article) and Quality Bias (authors selectively self-archiving their higher quality articles – a non-causal component: disappears at 100% OA). We are currently comparing the OA advantage for mandated and spontaneous (self-selected) self-archiving. Deposit rates in Institutional Repositories (IRs) remain at 15% if unmandated, but climb toward 100% OA if mandated, confirming surveys that predicted 95% compliance. In the UK, 4 of the 8 research funding councils and the Wellcome Trust mandate self-archiving and it is being considered by the European Commission and the US federal FRPAA. There is no reason for universities to wait for the passage of the legislation. Five universities and two research institutions (including CERN) have already mandated it, with documented success. An Immediate-Deposit/Optional-Access Mandate covers all cases and moots all legal issues: metadata are immediately visible webwide and, where needed, access to the postprint can be set as Closed Access instead of OA throughout any embargo period. Software to support this approach (that allows the author to email individual copies of non-Open Access papers to individual requesters) has been created for both EPrints and DSpace repository platforms

    Techniques avancées d'optimisation pour la résolution du problÚme de stockage de conteneurs dans un port

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    The loading and unloading of containers and their temporary storage in the container terminal are the most important and complex operation in seaport terminals. It is highly inter-related with the routing of yard crane and truck and their costs increased significantly especially without an efficient terminal management. To improve this process, an efficiency decision for the container storage space allocation must be taken.In this thesis, we studied the container storage problem (CSP). It falls into the category of NP hard and NP complete problems. CSP consists on finding the most suitable storage location for incoming containers that minimizes rehandling operations of containers during their transfer to the ship, truck or train. In fact, the wait time of customer trucks, the transfer time of yard crane and the Ship turnaround time are advantageously reduced.Generally, this problem is studied considering a single container type. However, this does not stand the problem under its real-life statement as there are multiple container types that should be considered, (refrigerated, open side, empty, dry, open top and tank). Often, containers arrive at the port dynamically over time and have an uncertain departure date (ship delayed, a ship down, delayed arrival of customer trucks
). Indeed, CSP must be studied in dynamic aspectThe objective of this thesis is to study Static CSP for a single and various container type and dynamic CSP for ONE and several container types and to propose solutions for each of them. Genetic algorithm and Harmony Search algorithm are used to solve these problems and we compare the results of each approach with the LIFO algorithmLe chargement/dĂ©chargement des conteneurs et leurs stockages provisoires dans le port est la plus importante et complexe tĂąche dans les terminaux portuaires. Elle est fortement liĂ©e au routage des grues de quai et son coĂ»t augmente considĂ©rablement surtout en absence d’une gestion efficace du terminal. Dans ce travail, nous Ă©tudions le problĂšme de stockage des conteneurs (PSC). Il appartient Ă  la catĂ©gorie des problĂšmes NP-difficiles et NP-complets. PSC consiste Ă  dĂ©terminer un plan d’arrangement des conteneurs destinĂ©s Ă  l’import et Ă  l’export dans le port qui minimise les remaniements ultĂ©rieurs lors de leur transfert vers le bateau, camion ou train. En effet, le temps d'attente des camions des clients, le temps de transfert des grues de quai et le temps nĂ©cessaire au chargement/dĂ©chargement du navire sont avantageusement rĂ©duits. PSC est gĂ©nĂ©ralement Ă©tudiĂ© en considĂ©rant un seul type de conteneur. Cependant, plusieurs types de conteneurs sont utilisĂ©s dans les ports maritimes (dry, rĂ©frigĂ©rĂ©s, toit ouvert,...). En outre, le problĂšme de stockage de conteneurs peut ĂȘtre traitĂ© de façon statique ou dynamique (date d’arrivĂ©e et de dĂ©part des conteneurs incertains).L’objectif de cette thĂšse est de rĂ©soudre le PSC statique et le PSC dynamique pour un seul et plusieurs types de conteneurs en utilisant deux mĂ©taheuristiques : l’algorithme gĂ©nĂ©tique, la recherche harmoniquePour vĂ©rifier la performance de chacune des approches proposĂ©es, une Ă©tude comparative des rĂ©sultats gĂ©nĂ©rĂ©s par chaque mĂ©thode ainsi que celle de l’algorithme LIFO est Ă©tabli

    Complementarities between organizational changes, R&D activity and technological cooperation for the French manufacturing firms

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    This article analyzes the determinants of the French companies’ innovation activity while highlighting the importance and the complementarities of the organizational and technological practices’impact. Our results suggest on one hand, that the product or process innovation is determined by the internal and external attributes of the company (size, demand pull and technological class). On the other hand, the complementarities tests between the technological (R&D activity and technological partnership) and organizational practices showed that these strategies are interconnected and that they have complementary effects which call for their simultaneous adoption. Accordingly, to be able to benefit completely from the positive effect of the partnership and the R&D efforts on innovation, they must be accompanied by certain organizational practices related to a good skills management and the implementation of an organizational architecture facilitating the knowledge creation and sharing

    Open access increases citations of papers in ecology

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    Open access (OA) can effectively increase the accessibility and visibility of scientific articles and thus potentially confer them with citation advantages. Such an impact may be more pronounced in developing countries where the cost for journal subscription is comparably expensive and usually unaffordable. By comparing one OA article with one non‐OA article published in the same issue, we tested the impact of OA on citation advantages of articles published in 46 ecology journals indexed in the Journal Citation Reports (JCR). We compared OA to non‐OA articles published in the same issue of these journals, thereby controlling for potentially confounding effects of publication requirement and period. OA articles received significantly more citations than non‐OA articles, and this citation advantage of approximately one citation per year was sustained across publication years from 2009 to 2013. The OA citation advantage did not depend upon income of the country of origin of the citing scientists, and the OA citation advantage was found for citing scientists from North America, Europe, Asia, Africa, and Oceania, but not for Latin America. A total of 10 countries contributed more than 1000 citations each, and the OA citation advantage was found in all the 10 countries except Canada. Therefore, in ecology journals OA confers articles with citation advantages and such an impact accumulates with years and independent of the economic status of the countries. This information may guide decisions of scientific societies, journals, and individual authors as they weigh the relative costs and benefits of open electronic accessibility of scientific research

    Fractional modeling of wind speed turbulence

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    This paper proposes a method to design a wind turbulence model based on real wind spectral characteristics. It uses models based on Cole-Cole fractional functions to approximate the wind turbulence power spectral density. Von KĂĄrmĂĄn model is the most commonly used model but originally designed for aircraft in high altitude. Therefore, it is not suitable for systems operating at low altitude, hence the need for more accurate models in these specific conditions. Shaping filters issued from the fractional models are employed to generate realistic random wind speed turbulence from a random white noise input. Then, a grey box model is proposed from physical parameters such as the classic von KĂĄrmĂĄn ones (mean speed, turbulence intensity and length scale)
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