1,720,994 research outputs found
Data-driven digital twin of a chemical production site for production and utilities planning
Get PDFThe BASF Antwerp site is one of the most advanced and integrated chemical production sites of the BASF group and worldwide. The chemical plants on site are heavily interconnected, i.e., the product of one plant is the raw material used in the next one and some of the plants use the steam produced from neighboring ones. This high degree of interconnection makes it quite difficult to assess the feasibility let alone the economic optimality of production and maintenance plans for the entire site. This research explores the use of a data-driven digital twin to simulate and assess these plans. Two value chains, i.e., a collection of plants converting raw material to valuable end products have been selected as a proof-of-concept for the entire site. Each plant has been modeled by utilizing simple or multiple regression. Each regression model correlates the final product of a plant with the needed raw materials or utilities (e.g., steam or electricity). All regression models have been found using the software JMP. Additionally, all relevant tanks used to stock raw materials, intermediates and final products have been modelled. This allowed for the visualization and troubleshooting of a particular component excess or shortage. The resulting system of 76 variables has been solved in MATLAB in a multi-period fashion, where a period represents a day. The simulation has been first performed on the training data set, and then on a validation period to verify the models' performance
Value chain planning optimization: a data driven digital twin approach
Get PDFThe long term production planning for a large chemical production site, where 10+ different chemical plants share raw materials, infrastructure (e.g., tank farm, filling stations) and utilities (e.g. steam, electricity, technical gasses) might prove to be a challenging task. This paper introduces a data driven approach to build a digital twin of a chemical production site to aid the relevant decision makers in defining and evaluating the economic impact of a long term (i.e. several months ahead) production planning. Each chemical plant and energy production unit on site is represented by simple regression models relating the consumption of raw materials and utilities to its products. The resulting system of algebraic equations has been inserted in an optimization environment with the objective of maximizing the profit. In the optimization, also the electricity and steam generation were introduced to obtain a global energy balance of the production site. This combination resulted in a multi period Mixed-Integer Linear Programming (MILP) problem. The effect of electricity price and external temperature on the optimization results are also investigated
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Get PDFWe 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
Get PDFWe 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
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe 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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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