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    Uthyrningsbehov av byggmaskiner baserat på projektkaraktär: Prediktiv modellering med maskininlärning

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    För uthyrningsföretag som Skanska Rental, finns det en stor nytta av att kunna prediktera uthyrningsbehovet av deras produkter för att kunna säkerställa att rätt maskiner och utrustning finns tillgängliga för kunderna samt för att kunna investera i nya, efterfrågade produkter. Detta examensarbete introducerar tre olika modelltyper i form av random forest, support vector machine och logistisk regression som testades med två olika typer av klassificeringsmetoder, binär relevans samt klassificeringskedja, för att kunna prediktera maskinuthyrningsbehovet. Modellerna som gjordes var multi-label klassificeringar där varje klass representerar en maskintyp. Modelleringen gjordes på två olika dataset med olika uppsättningar av förklarande variabler. Gemensamt för de båda dataseten var att modellerna med klassificeringskedja presterade bättre än de med binär relevans vilket tyder på att det finns beroenden mellan maskintyperna. Resultaten visar på att maskininlärningsmodeller kan användas för att ge indikationer på uthyrningsbehovet men det finns stora variationer i modellprestanda mellan olika maskintyper. Variabler som beskriver typ av byggnation verkar vara mer betydelsefulla för predikteringen jämfört med variabler som beskriver ekonomiska faktorer eller projektlängd. Vidare visar examensarbetet på att det finns tydliga skillnader i byggmaskinsbehovet baserat på projektkaraktär. For rental companies like Skanska Rental, there is great benefit in being able to predict the rental demand for their products to ensure that the right machines and equipment are available for customers and to invest in new, demanded products. This thesis introduces three different model types in the form of random forest, support vector machine and logistic regression which were tested with two different types of classification methods, binary relevance and classifier chain, to predict machine demand. The models created were multi-label classifications where each class represents a machine type. The modeling was done on two different datasets with different sets of explanatory variables. Common to both datasets was that the models with classifier chains performed better than those with binary relevance, indicating dependencies between different machine types. The results show that machine learning models can be used to provide indications of rental demands, but there are large variations in model performance between the different machine types. Variables describing type of construction seem to be more significant for prediction compared to variables describing economic factors or project duration. Furthermore, the thesis shows that there are clear differences in construction machine needs based on project characteristics.

    Uthyrningsbehov av byggmaskiner baserat på projektkaraktär: Prediktiv modellering med maskininlärning

    No full text
    För uthyrningsföretag som Skanska Rental, finns det en stor nytta av att kunna prediktera uthyrningsbehovet av deras produkter för att kunna säkerställa att rätt maskiner och utrustning finns tillgängliga för kunderna samt för att kunna investera i nya, efterfrågade produkter. Detta examensarbete introducerar tre olika modelltyper i form av random forest, support vector machine och logistisk regression som testades med två olika typer av klassificeringsmetoder, binär relevans samt klassificeringskedja, för att kunna prediktera maskinuthyrningsbehovet. Modellerna som gjordes var multi-label klassificeringar där varje klass representerar en maskintyp. Modelleringen gjordes på två olika dataset med olika uppsättningar av förklarande variabler. Gemensamt för de båda dataseten var att modellerna med klassificeringskedja presterade bättre än de med binär relevans vilket tyder på att det finns beroenden mellan maskintyperna. Resultaten visar på att maskininlärningsmodeller kan användas för att ge indikationer på uthyrningsbehovet men det finns stora variationer i modellprestanda mellan olika maskintyper. Variabler som beskriver typ av byggnation verkar vara mer betydelsefulla för predikteringen jämfört med variabler som beskriver ekonomiska faktorer eller projektlängd. Vidare visar examensarbetet på att det finns tydliga skillnader i byggmaskinsbehovet baserat på projektkaraktär. For rental companies like Skanska Rental, there is great benefit in being able to predict the rental demand for their products to ensure that the right machines and equipment are available for customers and to invest in new, demanded products. This thesis introduces three different model types in the form of random forest, support vector machine and logistic regression which were tested with two different types of classification methods, binary relevance and classifier chain, to predict machine demand. The models created were multi-label classifications where each class represents a machine type. The modeling was done on two different datasets with different sets of explanatory variables. Common to both datasets was that the models with classifier chains performed better than those with binary relevance, indicating dependencies between different machine types. The results show that machine learning models can be used to provide indications of rental demands, but there are large variations in model performance between the different machine types. Variables describing type of construction seem to be more significant for prediction compared to variables describing economic factors or project duration. Furthermore, the thesis shows that there are clear differences in construction machine needs based on project characteristics.

    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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    Nao informado

    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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