1,720,966 research outputs found
Transformations for Variants of the Travelling Salesman Problem and Applications
No full textA Master of Science thesis in Engineering Systems Management by Mustafa Jamil Assaf entitled, "Transformations for Variants of the Travelling Salesman Problem and Applications," submitted in April 2017. Thesis advisor is Dr Malick Ndiaye. Soft and hard copy available.The Travelling Salesman Problem (TSP) is a well-known problem in the operations research field. This research focuses on solving variants of the TSP through the use of proper transformations, which allows the use of existing solution approaches and algorithms. In this thesis, a comprehensive review with graphical illustrations is provided for the multiple Travelling Salesmen problem (mTSP) and the Multi Depot multiple Travelling Salesmen Problem (MmTSP) transformations that are available in the literature. Furthermore, several variants were solved for the MmTSP such as the Fixed Destination MmTSP, Non-Fixed Destination MmTSP and the Open Path MmTSP through formulated transformations based on duplicated and dummy depots. Solving mTSP and MmTSP variants through duplicating the depots is very traditional, while the use of dummy nodes is not common. We proved that the proposed transformations yield the same optimal solutions for the different variants. Then, numerical testing was used to validate the transformations. Also, a new variant of the TSP is introduced and the Mixed Integer Linear Programming (MILP) formulation is provided. In this variant, salesmen are allowed to start from any city, unlike the traditional TSP and its variants where salesmen are bind to start from a predetermined node. The proposed solution is done by adding dummy nodes that serve as depots to the regular TSP problem. We refer to this model as the Depot-less Travelling Salesmen Problem (DTSP). For the validation of the work, the model is used to solve an already existing problem from the online TSP library via an optimization software. Later, the proposed model is applied to solve supervisors' allocation problem and a clustering problem. Our results confirm that both the transformed and the original graphs yield the same answer, which is the main purpose of using transformation.College of EngineeringDepartment of Industrial EngineeringMaster of Science in Engineering Systems Management (MSESM
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
Photosynthetic variability along an elevational gradient in the chaparral
No full textA field study was conducted on the incorporation of the Carbon-14 by several chaparral species along an elevational transect from the coast to inland California in San Diego county. Measurements were carried out under natural conditions and included photosynthesis, xylen water potentials, light intensity, air temperature, and leaf density.
The results show that the evergreen sclerophyllous shrubs have higher rates of daily carbon uptake at high elevations than at low elevation. This is correlated with higher precipitation at high elevations of the chaparral. Among the evergreen shrubs, the shallow rooted(e.g. C.greggii shrubs)indicated more water stress and an earlier decline in their carbon uptake with advancing drought than did the deep rooted shrubs (e.g. A. fasciculatum and Q. dumosa). The dependence of the daily carbon uptake on dawn water potentials is well illustrated in A. fasciculatum, an evergreen shrub that was sampled at all elevations, and in the drought-deciduous shrubs S. apiana and S. mellifera that occurred at low elevations of the transect.Oechel Walter C., Mustafa Jamil. Photosynthetic variability along an elevational gradient in the chaparral. In: Ecologia mediterranea, tome 8 n°1-2, 1982. Définition et localisation des écosystèmes méditerranéens terrestres / Definition and localization of terrestrian Mediterranean biota. Saint-Maximin (France) 16-20/11/81. pp. 417-433
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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