104,844 research outputs found
The effect of water related traps on the reliability of organic based transistors
No full textThe electrical stability of metal-insulator semiconductor (MIS) capacitors and field-effect transistor structures based in organic semiconductors were investigated. The device characteristics were studied using steady state measurements AC admittance measurements as well as techniques for addressing trap states. Temperature-dependent measurements show clear evidence that an electrical instability occurs above 200 K and is caused by an electronic trapping process. Experimental results show that water is responsible for the trapping mechanism. (c) 2006 Elsevier B.V. All rights reserved
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Appropriate Similarity Measures for Author Cocitation Analysis
No full textWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Drift kappenspuit bij onkruidbestrijding in de boomteelt : veldmetingen 2011
No full textVoor neerwaartse bespuitingen in de boomteelt (laan - en parkbomen, bos - en haagplantsoen, vruchtbomen, rozestruiken, sierconiferen, etc.) wordt nu gebruik gemaakt van de driftcijfers voor veldspuiten. Deze driftcijfers zijn afgeleid van bespuitingen in aardappelen met een veldspuit. Onkruidbestrijding wordt in de boomteelt echter vooral uitgevoerd met spuitboompjes die laag boven het grondoppervlak (max. 3 0 cm) bewegen met neerwaarts gerichte spuitdoppen. Aangenomen mag worden dat de drift bij deze toepassing aanzienlijk lager zal zijn dan bij een bespuiting van aardappelen (50 cm boomhoogte boven een gewas van 50 - 75 cm hoog). Om de optredende drift bij onkruidbespuitingen in de boomteelt te kwantificeren en aan te tonen dat de drift lager is dan het nu gehanteerde driftpercentage in het Toelatingsbeleid (Ctgb, 2012; 1% driftdepositie op wateroppervlak) zijn in 2010 en 2011 veldmetingen uitgevo erd in een perceel laanbomen (Stallinga et al. , 2012). De percelen waren beschikbaar omdat daar driftmetingen bij gebruik van een mastspuit in de hoge laanbomen uitgevoerd werden (Stallinga et al. , 2011). In de boomteelt worden bespuitingen ook uitgevoerd met een zogenaamde kappenspuit. De spuitdoppen worden hierbij afgeschermd met een kap, zodat uitsluitend het onkruid geraakt wordt en niet de gewasplanten. Om de mate van driftbeperking door een kappenspuit vast te stellen zijn in 2011 veldmetingen uitgevoerd
Dispelling the Myths Behind First-author Citation Counts
No full textWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
The construction of Karen Karnak: The multi-author-function
No full textThis thesis is situated within the comparatively recent developments of Web 2.0 and the emergence of interactive WikiMedia, and explores the mode of authorship within a Read/Write culture compared to that of a Read/Only tradition. The hypothesis of this study is that the role of the audience has become merged with the author, and as such, represents new functions and attributes, distinct from a more conventional concept of authorship, in which the roles of audience and author are more separate. Read/Write and participatory culture, as defined by this study, is focused on collaboration, and includes the influences of D.I.Y. culture, Open-Source practices and the production of text by multiple authors. Multi-authorship presents a re-thinking of several concepts which support the notion of the individual author, since the focus of multi-authorship is not on attribution and ownership of a finished text, but on the continued malleability of a text. Modes of multi-authorship, demonstrated in the use of the pseudonyms Alan Smithee and Karen Eliot, represent declarative authors whose names signify multiple origins, whilst concurrently indicating a distinct body of work. The function of these names form an important context to this study, since primary research involves the construction of an experimental mode of multi-authorship utilising WikiMedia technology and the interaction of thirty nine participants, who are invited to create a body of work under the collective pseudonym Karen Karnak. The data generated by this experiment is analysed using aspects of Michel Foucault's author-function to identify and determine power structures inherent in the WikiMedia context. The interplay of power structures, including concepts such as identity, ownership and the body of work, affect the resulting mode of authorship and contribute to the construction of Karen Karnak, suggesting further areas of research into the emerging multi-author
Electronic Transport in Field Effect Transistors of Sexithiophene
No full textThe electronic conduction of thin-film field-effect-transistors (FETs) of sexithiophene was studied. In most cases the transfer curves deviate from standard FET theory; they are not linear, but follow a power law instead. These results are compared to conduction models of "variable-range hopping" and "multi-trap-and-release". The accompanying IV curves follow a Poole-Frenkel (exponential) dependence on the drain voltage. The results are explained assuming a huge density of traps. Below 200 K, the activation energy for conduction was found to be ca. 0.17 eV. The activation energies of the mobility follow the Meyer-Neldel rule. A sharp transition is seen in the behavior of the devices at around 200 K. The difference in behavior of a micro-FET and a submicron FET is shown. (C) 2004 American Institute of Physics
Contribution of Information and Communication Technology (ICT) in Country’S H-Index
No full textThe aim of this study is to examine the effect of Information and Communication Technology (ICT) development on country’s scientific ranking as measured by H-index. Moreover, this study applies ICT development sub-indices including ICT Use, ICT Access and ICT skill to find the distinct effect of these sub-indices on country’s H-index. To this purpose, required data for the panel of 14 Middle East countries over the period 1995 to 2009 is collected. Findings of the current study show that ICT development increases the H-index of the sample countries. The results also indicate that ICT Use and ICT Skill sub-indices positively contribute to higher H-index but the effect of ICT access on country’s H-index is not clear
Fully Turbulent Mean Velocity Profile for Purely Viscous non-Newtonian Fluids
No full textThe characteristic near wall behavior of turbulent flow of purely-viscous non-Newtonian fluids is discussed for both power-law (P.-L.) and Herschel-Bulkley (H.-B.) rheological models. A proper scaling is presented for H.-B. fluids to establish an analogy with power-law fluids with same flow index. To provide reference data for turbulent flow of non-Newtonian fluids, DNS simulations of power-law fluids are conducted in a rectangular channel for a large range of power-law indices ( = 0.5, 0.69, 0.75, 0.9, 1, 1.2). The DNS data show that the mean velocity profile in the viscous and logarithmic layers follow expressions of the form and respectively, where shows a logarithmic dependency on the flow index.Comparison with some experimental data shows the above formulation to be valid for Reynolds numbers (based on shear velocity) as high as 1000
Drift kappenspuit bij onkruidbestrijding in de boomteelt : veldmetingen 2011
No full textVoor neerwaartse bespuitingen in de boomteelt (laan - en parkbomen, bos - en haagplantsoen, vruchtbomen, rozestruiken, sierconiferen, etc.) wordt nu gebruik gemaakt van de driftcijfers voor veldspuiten. Deze driftcijfers zijn afgeleid van bespuitingen in aardappelen met een veldspuit. Onkruidbestrijding wordt in de boomteelt echter vooral uitgevoerd met spuitboompjes die laag boven het grondoppervlak (max. 3 0 cm) bewegen met neerwaarts gerichte spuitdoppen. Aangenomen mag worden dat de drift bij deze toepassing aanzienlijk lager zal zijn dan bij een bespuiting van aardappelen (50 cm boomhoogte boven een gewas van 50 - 75 cm hoog). Om de optredende drift bij onkruidbespuitingen in de boomteelt te kwantificeren en aan te tonen dat de drift lager is dan het nu gehanteerde driftpercentage in het Toelatingsbeleid (Ctgb, 2012; 1% driftdepositie op wateroppervlak) zijn in 2010 en 2011 veldmetingen uitgevo erd in een perceel laanbomen (Stallinga et al. , 2012). De percelen waren beschikbaar omdat daar driftmetingen bij gebruik van een mastspuit in de hoge laanbomen uitgevoerd werden (Stallinga et al. , 2011). In de boomteelt worden bespuitingen ook uitgevoerd met een zogenaamde kappenspuit. De spuitdoppen worden hierbij afgeschermd met een kap, zodat uitsluitend het onkruid geraakt wordt en niet de gewasplanten. Om de mate van driftbeperking door een kappenspuit vast te stellen zijn in 2011 veldmetingen uitgevoerd
- …
