1,720,961 research outputs found
Ortak kümeleme kullanarak 3b iç mekan sahne bölütlenmesi
No full textIn this study, we propose an indoor scene segmentation method which utilizes consensus clustering. Unlike most of the recently offered methods in literature, our approach does not rely on deep learning techniques. Therefore, it does not require a large dataset for training and spending a lot of time to learn a valid model is not necessary. In the first step of our algorithm, we construct uniform and cotangent Laplace operators. Then, we compute differential coordinates using them and global point signatures using the eigenbasis of cotangent Laplace operator. In the next step, we use these coordinates and global point signatures as features and run k-medoids multiple times to create an ensemble. With the help of Partial Evidence Accumulation Clustering method, which is a consensus clustering approach, we obtain the final segmentation. Optionally, we offer an interactive segmentation mechanism to our users, in case any adjustment on the final segmentation is needed. The key idea of our approach is to use a specialized function to compute distance between feature points, which takes the scene geometry into account by using surface properties such as normals. At the end of the thesis, we also present both qualitative and quantitative evaluation of our method and show that it outperforms some of the existing techniques, quantitatively.Bu çalı¸smada, iç mekan sahnelerinin bölütlenmesi sorununa ortak kümeleme kullanan bir yöntem öneriyoruz. Literatüre sunulan son çalı¸smaların çogunlu gunun aksine,
önerdigimiz yöntem derin ö ˘ grenme tekniklerine dayanmamaktadır. Bu nedenle, büyük veri kümelerine ihtiyaç duymamaktadır ve geçerli bir model ögrenmek için çok
zaman harcamasına gerek yoktur. Algoritmanın ilk adımında, tekdüze ve kotanjant Laplace operatörleri olu¸sturuyoruz. Sonra, Laplace operatörlerini kullanarak diferansiyel koordinatları ve kotanjant Laplace operatörünün eigen bazını kullanarak evrensel nokta imzalarını hesaplıyoruz. Sonraki adımda, bu koordinatları ve evrensel nokta imzalarını nitelik olarak kullanıyor ve topluluk olu¸sturmak için çok kere k-medoids çalı¸stırıyoruz. Bir ortak kümeleme yakla¸sımı olan Kısmı Kanıt Biriktirme Kümelenmesi yönteminin yardımıyla, nihai bölütlemeyi elde ediyoruz. ˙Istege ba ˘ glı olarak, eger nihai bölütleme üzerinde herhangi bir düzenleme gerekli görülürse, kullanıcılarımıza bir etkile¸simli bölütleme mekanizması sunuyoruz. Yakla¸sımımızın kilit fikri nitelik noktaları arasındaki mesafe hesaplanırken, normaller gibi yüzey özelliklerini kullanarak sahne geometrisini dikkate alan özelleşmiş bir fonksiyon kullanılmasıdır. Tezin sonunda, yöntemimizin hem nitel hem de nicel degerlendirmesini sunuyor ve varolan bazı tekniklerden nicel olarak daha üstün oldugunu gösteriyoruzM.S. - Master of Scienc
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
3D Shape Deformation Using Stick Figures
No full textObtaining new poses of an articulated character is a critical task in computer graphics. We address this issue with a new shape deformation approach consisting of two phases enabling the user to express the new pose as a simple stick figure, also called skeleton consisting of few bones. We interchangeably refer to this problem as shape transfer because the template shape is transferred to the independent stick figure that may be obtained from any source such as motion capture and 3D sketching. In the first phase, the stick figure is embedded into the template shape, resembling the rigging process of character skinning. Then, instead of computing blend weights as in skinning, the shape, discretized as a mesh, is augmented by adding extra edges between a subset of mesh vertices and the embedded stick figure. The second phase deforms the augmented mesh towards the new pose under the guidance of the embedded stick figure by minimizing an As-Rigid-As-Possible (ARAP) energy. The overall deformation is intuitive as skinning, preserves surface details as it is based on ARAP deformation yet has better volume preservation capability owing to the augmented mesh. Our results are validated both in terms of timing and accuracy in a comprehensive test suite that includes state-of-the-art deformation techniques. (C) 2022 Elsevier Ltd. All rights reserved
Scale Normalization for Isometric Shape Matching
No full textWe address the scale problem inherent to isometric shape correspondence in a combinatorial matching framework. We consider a particular setting of the general correspondence problem where one of the two shapes to be matched is an isometric (or nearly isometric) part of the other up to an arbitrary scale. We resolve the scale ambiguity by finding a coarse matching between shape extremities based on a novel scale-invariant isometric distortion measure. The proposed algorithm also supports (partial) dense matching, that alleviates the symmetric flip problem due to initial coarse sampling. We test the performance of our matching algorithm on several shape datasets in comparison to state of the art. Our method proves useful, not only for partial matching, but also for complete matching of semantically similar hybrid shape pairs whose maximum geodesic distances may not be compatible, a case that would fail most of the conventional isometric shape matchers.Computer Graphics Forum3
Coarse-to-Fine Combinatorial Matching for Dense Isometric Shape Correspondence
No full textWe present a dense correspondence method for isometric shapes, which is accurate yet computationally efficient. We minimize the isometric distortion directly in the 3D Euclidean space, i.e., in the domain where isometry is originally defined, by using a coarse-to-fine sampling and combinatorial matching algorithm. Our method does not require any initialization and aims to find an accurate solution in the minimum-distortion sense for perfectly isometric shapes. We demonstrate the performance of our method on various isometric (or nearly isometric) pairs of shapes.Computer Graphics Foru
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
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