Browsing by Subject "Hybrid approach"

Now showing 1 - 5 of 5

Open Access
Data and model driven hybrid approach to activity scoring of cyclic pathways
(Springer, Dordrecht, 2010) Işık, Z.; Atalay V.; Aykanat, Cevdet; Çetin-Atalay, Rengül
Analysis of large scale -omics data based on a single tool remains inefficient to reveal molecular basis of cellular events. Therefore, data integration from multiple heterogeneous sources is highly desirable and required. In this study, we developed a data- and model-driven hybrid approach to evaluate biological activity of cellular processes. Biological pathway models were taken as graphs and gene scores were transferred through neighbouring nodes of these graphs. An activity score describes the behaviour of a specific biological process was computed by owing of converged gene scores until reaching a target process. Biological pathway model based approach that we describe in this study is a novel approach in which converged scores are calculated for the cellular processes of a cyclic pathway. The convergence of the activity scores for cyclic graphs were demonstrated on the KEGG pathways. © 2011 Springer Science+Business Media B.V.
Open Access
A hybrid approach for line segmentation in handwritten documents
(2012) Adıgüzel, Hande; Şahin, Emre; Duygulu, Pınar
This paper presents an approach for text line segmentation which combines connected component based and projection based information to take advantage of aspects of both methods. The proposed system finds baselines of each connected component. Lines are detected by grouping baselines of connected components belonging to each line by projection information. Components are assigned to lines according to different distance metrics with respect to their size. This study is one of the rare studies that apply line segmentation to Ottoman documents. Further, it proposes a new method, Fourier curve fitting, to detect the peaks in a projection profile. The algorithm is demonstrated on different printed and handwritten Ottoman datasets. Results show that the method manages to segment lines both from printed and handwritten documents under different writing conditions at least with 92% accuracy.
Open Access
A novel hybrid approach for interestingness analysis of classification rules
(Springer, Berlin, Heidelberg, 2007) Aydın, Tolga; Güvenir, Halil Altay
Data mining is the efficient discovery of patterns in large databases, and classification rules are perhaps the most important type of patterns in data mining applications. However, the number of such classification rules is generally very big that selection of interesting ones among all discovered rules becomes an important task. In this paper, factors related to the interestingness of a rule are investigated and some new factors are proposed. Following this, an interactive rule interestingness-learning algorithm (IRIL) is developed to automatically label the classification rules either as "interesting" or "uninteresting" with limited user participation. In our study, VFP (Voting Feature Projections), a feature projection based incremental classification learning algorithm, is also developed in the framework of IRIL. The concept description learned by the VFP algorithm constitutes a novel hybrid approach for interestingness analysis of classification rules. © Springer-Verlag Berlin Heidelberg 2007.
Open Access
Physically-based simulation of hair strips in real-time
(UNION Agency - Science Press, 2005) Taşkıran, Hasan Dogu; Güdükbay, Uğur
In this paper, we present our implementation of physically-based simulation of hair strips. We used a mass-spring model followed by a hybrid approach where particle systems and the method of clustering of hair strands are employed. All the forces related to springs are implemented: gravity, repulsions from collisions (head and ground), absorption (ground only), frictions (ground and air), internal spring frictions. Real-time performance is achieved for physically-based simulation of hair strips and promising results in terms of the realistic hair behavior and hair rendering are obtained. Copyright UNION Agency - Science Press.
Open Access
Strategies for setting time-to-live values in result caches
(ACM, 2013-10-11) Sazoğlu, Fethi Burak; Cambazoğlu, B. B.; Özcan, R.; Altıngövde, İsmail Şengör; Ulusoy, Özgür
In web query result caching, staleness of queries are often bounded via a time-to-live (TTL) mechanism, which expires the validity of cached query results at some point in time. In this work, we evaluate the performance of three alternative TTL mechanisms: time-based TTL, frequency-based TTL, and click-based TTL. Moreover, we propose hybrid approaches obtained by pair-wise combination of these mechanisms. Our results indicate that combining time-based TTL with frequency-based TTL yields superior performance (i.e., lower stale query traffic and less redundant computation) than using a particular mechanism in isolation. Copyright is held by the owner/author(s).