1,720,955 research outputs found
Scheduling of waiting queues in manufacturing workprocess using a human reliability measure
No full textIn the recent years the increasing recognition of the critical role of human factor in complex manufacturing
systems, has focused a new attention towards the Human Reliability Analysis (HRA). During the phases of
operations scheduling, engineers usually focus on problems caused by hardware, software or machinery
breakdowns and they seldom pay attention to problems caused by the human error, which significantly may
affect not only system reliability and safety but also the effectiveness of scheduling. The objective of the research
is to look for a job sequence, in a waiting queue, able to improve the economic “expected profit”, considering
the natural downsizing of the human performances during the workshift. Starting from a sequence of scheduled
jobs, the model analyses the human error probability (HEP) for each manual operation, and assesses its error
effects on the whole system. The model initially searches for the best job to be worked by the operator,
according to his reliability and specific HEP value; moreover it automatically determines, for that operator, the
optimal distribution of work pauses. The pauses are calculated in function of boundary causes that influence the
human reliability and are focused on the reduction of HEP. The proposed methodology determine, if it exists,
the optimal work sequence, that minimizes the HEP maximizing its deriving value of the global function of
profit
From ants colony to artificial ants: a nature inspired algorithm to solve job scheduling problems
No full textIncreased productivity and lower cost in manufacturing processes can be achieved through growing reduction of idle time so this justifies and requires a great deal to obtain an optimal scheduling. Newly, powerful methods for running optimization problems have been inspired by research on social insects’ behaviour and in particular on ants’ way. The cooperative behaviour that emerges from their organization has been dubbed as Swarm Intelligence. Ant System (AS) is a meta-heuristic approach with multi agent systems inspired by the foraging behaviour of real ant. Ants’ colony is able to find the shortest path among a lot of possible ones by stigmergic cooperation. This suitable framework joined with representation of a scheduling instance as graph, within each node represents an operation, makes the Ant Colony Optimization (ACO) algorithms well suited for scheduling duty. This paper deals with the application of an improved model based on ants’ way, with several specific rules incorporate, to schedule job shops associated with manufacturing operations with the aim to minimize the makespan. A comparison of solutions yielded by the proposed ant-colony algorithm with several priority dispatching rules and previous heuristic algorithms for several benchmark problems evinces that our model exhibits high performances
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
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