1,720,968 research outputs found
Sustainable and cost-effective optimal design of steel structures by minimizing cutting trim losses
Full text linkSince the beginning of the structural optimization field, the optimal design was characterized by the least-weight configuration. In this sense, all the researchers agreed on adopting the minimum-weight optimization statement as the most promising approach to achieve an optimized employment of material. However, especially for steel structures, this approach completely fails the primary goal of encouraging standardization of pieces during the production phase. Except for rare cases, increasing diversity among structural elements leads to a dramatic increase in the financial cost as well as the environmental impact of the structure because of the material waste generated during the cutting procedure. In this paper, a real-coded Genetic Algorithm has been adopted and the well-known one-dimensional Bin Packing Problem has been implemented within the structural optimization process. The Objective Function formulation lies in a marked change of the paradigm in which the target function is represented by the amount of steel required by the factory instead of the structural cost (e.g. weight). The proposed approach is tested on different steel structures moving from 2D truss beams to 3D domes. Addressing the optimal stock of existing elements leads to a significant waste reduction of 40% in almost all the investigated case studies
Constructability-based design approach for steel structures: From truss beams to real-world inspired industrial buildings
Full text linkThis paper presents an optimization framework for steel trusses. The authors implemented a penalty-based approach to optimise the size, shape, and topology based on a dynamic grouping strategy to address the constructability challenges. The main contribution of the paper is the use of damped exponential constructability penalties. This approach ensures optimal designs by balancing structural complexity, through standardization in design, and minimizing the total number of members and variety of sections, with the overall structural cost. The paper also presents a detailed analysis that underscores the sensitivity of the optimization convergence to the algorithmic hyperparameters, emphasizing the role of cross-section assignments and stabilization of truss piece counts. The optimization framework is validated on a trussed roof structure based on the findings from the single truss optimization. The best truss topology proved to be the Howe truss configuration, highlighting its efficiency in meeting the defined objective function
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Full text linkWe 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
Full text linkWe 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
Stiffness Ratio Evaluation of Steel Exoskeletons Through Performance-Based Optimal Design
Full text linkAmong the various seismic retrofitting techniques, steel exoskeletons are distinguished by their non-invasive nature. However, only a few consolidated methodologies have been proposed for their design. The approach of several standard codes is based on the classification of elements according to their relative stiffness. In this way, a ratio between the stiffness of the exoskeletons and that of the building is taken as the main design parameter. In this study, a performancebased design approach was employed, with the inter-story drift of the building as the performance target. A sensitivity analysis was conducted to assess the impact of different inter-story drift thresholds on the structural behavior of the buildingexoskeleton system. For each threshold, an optimization process was conducted to identify the optimal number of exoskeletons, their placement around the building, and the dimensions of their elements. Finally, the stiffness ratios were determined for each optimal configuration and were compared to the threshold provided by the regulations. This comparison yielded interesting insights into the differences in the approaches
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