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    Hydrogen Production from Wind and Solar Power in Weak Grids in Norway

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    In this thesis, the possibility of implementing an hydrogen factory in the north of Norway was studied through the simulation of the system and an optimization of the needed investment with the exclusion of the grid and in the first scenario of 10% of the production coming from electrolysis. The same study was then repeated multiple times to study how the previous results changes if the proportion of hydrogen produced by electrolysis is increased. The necessary grid upgrade to avoid rationing was also found out. The main results were that the investment in wind power was mainly at bus 9 and 8 and that even if the electrolyzer size increased approximately linearly, the storage size on the other hand does not and increase greatly after the case 40%. The possibility of investing in solar was then added to the model at a price of 3,8/Wpanditturnedouttonotbeprofitableatthispricebeforethecase50Thenextstepwastostudydifferentpricesinordertofindwhensolarbecomesprofitable.Theresultingvalueforthecase10/Wp and it turned out to not be profitable at this price before the case 50%. It was however found that the addition of solar power yields a positive impacts on the size of the storage needed due to advantageous seasonal effects. The next step was to study different prices in order to find when solar becomes profitable. The resulting value for the case 10% was around 0.4/Wp much lower than the current price of 1,6$/Wp but also reasonable in a longer term as suggested by some other studies. The next study was to account for the cost of the grid expansion in different cases to see if only limiting rationing is a good criteria. The simulation was used again with different grids and it appears that limiting the rationing was often giving the cheapest result even though upgrading the grid further do not result in a big increase in cost due to a trade off between operation cost and investment cost. The last study was focused on the behaviour of the hydro system during the previous simulation cases and it highlighted some interesting seasonal effect of the different technology. As of now, solar power does not appear to be a good solution for the case of 10% of the total hydrogen coming from electrolysis due to its cost. Wind power appears to be a preferable solution even if the investment is not large and thus does no take fully advantage of the resources of the north of Norway

    Hydrogen Production from Wind and Solar Power in Weak Grids in Norway

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    In this thesis, the possibility of implementing an hydrogen factory in the north of Norway was studied through the simulation of the system and an optimization of the needed investment with the exclusion of the grid and in the first scenario of 10% of the production coming from electrolysis. The same study was then repeated multiple times to study how the previous results changes if the proportion of hydrogen produced by electrolysis is increased. The necessary grid upgrade to avoid rationing was also found out. The main results were that the investment in wind power was mainly at bus 9 and 8 and that even if the electrolyzer size increased approximately linearly, the storage size on the other hand does not and increase greatly after the case 40%. The possibility of investing in solar was then added to the model at a price of 3,8/Wpanditturnedouttonotbeprofitableatthispricebeforethecase50Thenextstepwastostudydifferentpricesinordertofindwhensolarbecomesprofitable.Theresultingvalueforthecase10/Wp and it turned out to not be profitable at this price before the case 50%. It was however found that the addition of solar power yields a positive impacts on the size of the storage needed due to advantageous seasonal effects. The next step was to study different prices in order to find when solar becomes profitable. The resulting value for the case 10% was around 0.4/Wp much lower than the current price of 1,6$/Wp but also reasonable in a longer term as suggested by some other studies. The next study was to account for the cost of the grid expansion in different cases to see if only limiting rationing is a good criteria. The simulation was used again with different grids and it appears that limiting the rationing was often giving the cheapest result even though upgrading the grid further do not result in a big increase in cost due to a trade off between operation cost and investment cost. The last study was focused on the behaviour of the hydro system during the previous simulation cases and it highlighted some interesting seasonal effect of the different technology. As of now, solar power does not appear to be a good solution for the case of 10% of the total hydrogen coming from electrolysis due to its cost. Wind power appears to be a preferable solution even if the investment is not large and thus does no take fully advantage of the resources of the north of Norway

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The 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

    Variations on the Author

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    “Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship

    Appropriate Similarity Measures for Author Cocitation Analysis

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    We 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

    Dispelling the Myths Behind First-author Citation Counts

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    We 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

    Author Index

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    koamabayili/VECTRON-author-checklist: VECTRON author checklist

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    We have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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