Browsing by Subject "Visual analysis"

Now showing 1 - 6 of 6

Open Access
CMGV: a unified framework for complexity management in graph visualization
(2023-08) Zafar, Osama
In today’s era of technological revolution, the sheer volume of data being produced poses a significant challenge for analyzing relational data of such scale, particularly in terms of visual analysis. Graphs provide an effective way of organizing and representing relational data, with nodes representing entities. In contrast, edges representing relationships, a comprehensive and intuitive view of complex large-scale data is created. A well-represented visualization of complex graphs allows users to understand relationships, uncover new insights, and discover hid-den patterns. To this end, we introduce a complexity management framework for effectively analyzing large-scale relational data represented as graphs. Existing methods for managing graph complexity work independently and may lead to in-consistencies and confusion consecutively applied. The Complexity Management Graph Visualization framework (CMGV) presents a novel approach integrating commonly used complexity management techniques while ensuring the preservation of the user’s mental map through a specialized layout algorithm. The frame-work introduces an intuitive Graph Complexity Management Model (CMGM) for both graph representation and complexity management. CMGV supports commonly utilized complexity management tasks, including filtering, hiding, showing, collapsing, and expanding graph elements. Importantly, CMGV is designed to be independent of the rendering method and can be seamlessly integrated with different graph rendering libraries. This is possible through an extension that synchronizes the graph models between the rendering library and CMGM. Our experiments performed on randomly generated graphs verify that CMGV flawlessly performs consecutive graph complexity management operations, leaving the user graph intact, and outperforms existing complexity management solutions in terms of both runtime and generally accepted graph layout criteria. It is fast enough to be used in interactive applications with small to medium-sized graphs.
Open Access
Hydra: Detecting fraud in financial transactions via graph based representation and visual analysis
(IEEE, 2020) Canbaz, Yusuf Sait; Doğrusöz, Uğur; Çeliksoy, M.; Güngör, F.; Kurban, K.
In this paper, we describe a web based tool named Hydra for analyzing financial transaction data with the aim to detect or verify fraudulent activities via visual analysis and graph based querying. Hydra exclusively uses graph based query algorithms to mine useful information in the transaction database, presents the results visually, facilitating interactive graphical analysis with state-of-the-art graph visualization technologies. We present the various components of Hydra and their aims. In addition, a number of different types of scenarios using these components for a network of prepaid card transactions are provided to illustrate the use of Hydra for detecting or verifying fraudulent activities.
Open Access
Mapping out socio-cultural transformations through food packaging design in Turkey : a case study
(2005) Karamullaoğlu, Nazife
Exploration of the impact of socio-cultural transformations in the development of food packaging design and brand identity in Turkey, in the post-1980 period, is the focus of this research. Accordingly, this thesis explores the related and broad issues of modernization and convergence; globalization, consumption contexts and culture; internationalization of retailing; postmodernism and aestheticized (conspicuous) consumption in parallel with developments in food packaging design and brand identity. All these are tied and analyzed in a case study where in the collected samples, developments in domestic and foreign food packaging design and the corresponding brand identities are socio-semiotically related to the transformations in socio-cultural context in Turkey. Socio-semiotic method of analysis, along with visual style analysis, has provided a study of images in their social and material context which is in accordance with this field of research.
Open Access
Redif extraction in handwritten Ottoman literary texts
(IEEE, 2010) Can, Ethem F.; Duygulu, Pınar; Can, Fazlı; Kalpaklı, Mehmet
Repeated patterns, rhymes and redifs, are among the fundamental building blocks of Ottoman Divan poetry. They provide integrity of a poem by connecting its parts and bring a melody to its voice. In Ottoman literature, poets wrote their works by making use of the rhymes and redifs of previous poems according to the nazire (creative imitation) tradition either to prove their expertise or to show respect towards old masters. Automatic recognition of redifs would provide important data mining opportunities in literary analyses of Ottoman poetry where the majority of it is in handwritten form. In this study, we propose a matching criterion and method, Redif Extraction using Contour Segments (RECS) using the proposed matching criterion, that detects redifs in handwritten Ottoman literary texts using only visual analysis. Our method provides a success rate of 0.682 in a test collection of 100 poems. © 2010 IEEE.
Open Access
Tissue object patterns for segmentation in histopathological images
(ACM, 2011) Gündüz-Demir, Çiğdem
In the current practice of medicine, histopathological examination is the gold standard for routine clinical diagnosis and grading of cancer. However, as this examination involves the visual analysis of biopsies, it is subject to a considerable amount of observer variability. In order to decrease the variability, it has been proposed to develop systems that mathematically model the histopathological tissue images and automate the analysis. Segmentation constitutes the first step for most of these automated systems. Nevertheless, the segmentation in histopathological images remains a challenging task since these images typically show variances due to their complex nature and may include a large amount of noise and artifacts due to the tissue preparation procedures. In our research group, we recently developed different segmentation algorithms that rely on representing a tissue image with a set of tissue objects and using the structural pattern of these objects in segmentation. In this paper, we review these segmentation algorithms, discussing their clinical demonstrations on colon tissues. © 2011 ACM.
Open Access
Visuall: a quickly customizable library for jumpstarting visual graph analysis components
(2021-09) Canbaz, Yusuf Sait
Graph visualization is an area of information visualization, where relational data is depicted in the form of nodes (objects) and edges (links). Many people or organizations utilize graph visualization for insightful analysis and interpretation of relational data. In graph visualization, primary challenges include complexity management, eﬃcient database querying, and customization for speciﬁc domains. Visuall aims to solve these problems by providing a generic, highly customizable, and easily conﬁgurable software component for building web-based visual graph analysis tools. Essential functionalities needed by such visual analysis components include manually or automatically setting the layout of graph elements, support for nested or hierarchical drawings, eﬃcient querying of the database or client-side data, emphasizing or highlighting graph elements of interest, customization of visuals and styles, clustering, calculating graph-theoretical properties, and time-based ﬁltering of graph elements. Although Visuall provides all these functionalities out of the box for jumpstarting, customization of software for domain-speciﬁc needs is still unavoidable. Such software changes might result in complications due to unstructured code and code ignoring the invariants assumed by the orig-inal development team. To prevent these and to facilitate easily maintainable customization, Visuall provides a modular architecture. Furthermore, the devel-opers straightforwardly upgrade the software so long as the Visuall developers and the users developing visual analysis components based on Visuall maintain the provided architecture. We tested our database queries on a database that contains about half a million graph elements. We also examined our client-side operations up to a thousand graph elements. In both client-side and database operations, we observe that operations take at most several seconds, making Visuall convenient for interactive exploration and analysis of networks.