Bilgisayar Mühendisliği Bölümü Yayın Koleksiyonu
Permanent URI for this collectionhttps://hdl.handle.net/20.500.12416/253
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Article Citation - WoS: 14Citation - Scopus: 18Existence Theory and Numerical Simulation of HIV-I Cure Model with New Fractional Derivative Possessing a Non-Singular Kernel(Springeropen, 2019) Aliyu, Aliyu Lsa; Alshomrani, Ali Saleh; Li, Yongjin; Inc, Mustafa; Baleanu, DumitruIn this research work, a mathematical model related to HIV-I cure infection therapy consisting of three populations is investigated from the fractional calculus viewpoint. Fractional version of the model under consideration has been proposed. The proposed model is examined by using the Atangana-Baleanu fractional operator in the Caputo sense (ABC). The theory of Picard-Lindelof has been employed to prove existence and uniqueness of the special solutions of the proposed fractional-order model. Further, it is also shown that the non-negative hyper-plane a positively invariant region for the underlying model. Finally, to analyze the results, some numerical simulations are carried out via a numerical technique recently devised for finding approximate solutions of fractional-order dynamical systems. Upon comparison of the numerical simulations, it has been demonstrated that the proposed fractional-order model is more accurate than its classical version. All the necessary computations have been performed using MATLAB R2018a with double precision arithmetic.Article Citation - WoS: 3Citation - Scopus: 5Block Size Analysis for Discrete Wavelet Watermarking and Embedding a Vector Image as a Watermark(Zarka Private Univ, 2019) Sever, Hayri; Sever, Hayri; Senol, Ahmet; Elbasi, Ersin; Bilgisayar MühendisliğiAs telecommunication and computer technologies proliferate, most data are stored and transferred in digital format. Content owners, therefore, are searching for new technologies to protect copyrighted products in digital form. Image watermarking emerged as a technique for protecting image copyrights. Early studies on image watermarking used the pixel domain whereas modern watermarking methods convert a pixel based image to another domain and embed a watermark in the transform domain. This study aims to use, Block Discrete Wavelet Transform (BDWT) as the transform domain for embedding and extracting watermarks. This study consists of 2 parts. The first part investigates the effect of dividing an image into non overlapping blocks and transforming each image block to a DWT domain, independently. Then, effect of block size on watermark success and, how it is related to block size, are analyzed. The second part investigates embedding a vector image logo as a watermark. Vector images consist of geometric objects such as lines, circles and splines. Unlike pixel-based images, vector images do not lose quality due to scaling. Vector watermarks deteriorate very easily if the watermarked image is processed, such as compression or filtering. Special care must be taken when the embedded watermark is a vector image, such as adjusting the watermark strength or distributing the watermark data into the image. The relative importance of watermark data must be taken into account. To the best of our knowledge this study is the first to use a vector image as a watermark embedded in a host image.Article Petrol Flow Pattern Identification Via Data Mining Techniques(2012) Olcer, N.; Elbasi, E.Nowadays, petrol is an important resource for whole world, researchers are working on several mathematical models for flow pattern identification. One previous study is to find characterization of reservoir modeling in petrol flow data. Spatial data-mining can be used in reservoir geological research and ranking reservoir modeling. To find petrol flow patterns there is a study which aims to investigate and analyze the hole cleaning performance of gasified drilling fluids in horizontal, directional and vertical wells experimentally. Also, to identify the drilling parameters those have the major influence on cuttings transport, to define the flow pattern types and boundaries as well as to observe the behavior of cuttings in detail by using digital image processing techniques, and to develop a mechanistic model based on the fundamental principles of physics and mathematics with the help of the experimental observations. In this study we worked on petrol flow data with following features: mud flow rate, mud superficial velocity, pipe rotation per minute, rate of penetration, pressure transmitter and drill pipe. These features have been used in different classification and clustering algorithms to classify in nine class; Dispersed, Moving Bed, Stationary Bed, Dispersed Annular, Bubble, Elongated Bubble, Slug, Wavy Stratified, and Wavy Annular.We have received very promising results from 93% to 100% accuracy using different data mining algorithms. © Sila Science.Article Citation - WoS: 42Citation - Scopus: 50Mobile Language Learning: Contribution of Multimedia Messages Via Mobile Phones in Consolidating Vocabulary(Springer Heidelberg, 2012) Saran, Murat; Saran, Murat; Seferoglu, Golge; Cagiltay, Kursat; Bilgisayar MühendisliğiThis study aimed at investigating the effectiveness of using multimedia messages via mobile phones in helping language learners in consolidating vocabulary. The study followed a pre-test/post-test quasi-experimental research design. The participants of this study were a group of students attending the English Preparatory School of an English-medium university in Turkey. Six different groups were formed in order to investigate the comparative effectiveness of supplementary vocabulary materials delivered through three different means: via mobile phones, on web pages, and in print form. The multimedia messages in this study included the definitions of words, exemplary sentences, related visual representations, information on word formation, and pronunciations of words. Analyses of the quantitative data showed that using mobile phones had positive effects on students' vocabulary acquisition. The results suggest that mobile phones offer great potential for providing learners with supplementary opportunities to recontextualize, recycle, and consolidate vocabulary.Article Citation - WoS: 6Citation - Scopus: 7Illicit Material Detection Using Dual-Energy X-Ray Images(Zarka Private Univ, 2016) Hassanpour, Reza; Hassanpour, Reza; Yazılım MühendisliğiDual energy X-ray inspection systems are widely used in security and controlling systems. The performance of these systems however, degrades with the poor performance of human operators. Computer vision based systems are of vital importance in improving the detection rate of illicit materials, while keeping false alarms at a reasonably low level. In this study, a novel method is proposed for detecting material overlapping and reconstructing multiple images by alleviating these overlaps. Evaluation tests were conducted on images taken from luggage inspection X-ray screening devices used in shopping centres. The experimental results indicate that the reconstructed images are much easier to inspect by human operators than the unprocessed original images.Article Citation - WoS: 25Citation - Scopus: 31Supporting Foreign Language Vocabulary Learning Through Multimedia Messages Via Mobile Phones(Hacettepe Univ, 2010) Saran, Murat; Saran, Murat; Seferoglu, Goelge; Bilgisayar MühendisliğiThis study explored the effectiveness of mobile learning in foreign language education. With this purpose, instructional materials to be delivered through mobile phones operated in second generation GSM technology in order to improve English language learners' vocabulary acquisition were developed. The multimedia messages in this study allowed students to see the definitions of words, example sentences, related visual representations, and pronunciations. After students finished reading multimedia messages, interactive short message service (SMS) quizzes for testing their learning were sent. In addition, the study examined students' tendencies in using MMS in their second language vocabulary study and explored the opinions of the students toward the use of mobile phones for instructional purposes. The findings of this study suggest some important points to consider while creating MMS content and a SMS quiz system for educational purposes.Article Human Face Identification Using M-Pca Augmented With Gabor Wavelet(2005) Karaömeroǧlu, B.; Hassanpour, Reza; Hassanpour, R.; Yazılım MühendisliğiIn this paper, a specialized version of PCA augmented with Gabor Wavelet Transform is proposed for face identification. Firstly, to cope with the variations due to illumination and facial expression changes 2D Gabor Wavelet Transform is applied; then for reducing a large set of correlated variables to a small number of uncorrelated components the PCA approach is used with some modifications. Based on the effect of the illumination, facial expression and occluding objects such as eye glasses and facial hair, performance of the proposed algorithm is compared with the other algorithms.Article Citation - Scopus: 4Dynamic Binary Location Based Multi-Watermark Embedding Algorithm in Dwt(Asian Research Publishing Network, 2015) Hussein, A.J.; Yuksel, S.; Elbasi, E.In order to achieve a good imperceptibility and robustness, using 4-level DWT algorithm based on dynamic binary host image location and embedding two watermark logos in different DWT levels are proposed for copyright protection and authenticity. In the propounded watermarking algorithm, 5-level DWT is applied to host image to obtain the fifth low frequency sub band (LL5), and examination the dynamic binary location value of selected location for embedding purpose in five different locations in host image using the same algorithm process. Our experimental results demonstrate that our algorithm scheme is imperceptible and robust against several image processing attacks, and watermarked image quality evaluating by calculation of SNR, PSNR, RMSE, and MAE. © 2005 - 2015 JATIT & LLS. All rights reserved.Article Citation - Scopus: 6Design Effort Estimation Using Complexity Metrics(2004) Salman, N.; Salman, Nael; Doǧru, A.; Bilgisayar MühendisliğiComponent-oriented software development is a new trend and is becoming very popular these days. In addition to requiring a different development approach, the new orientation also requires a different metrics approach. A set of metrics for Component Oriented Software Engineering was first introduced in previous research. These metrics set were used to measure the quality of component-oriented software designs. The impact of these metrics on design effort is investigated in this paper. A statistical model is developed based on nine projects that carried out component-oriented software development. Design effort is expressed as a junction of a subset of the complexity metrics.Article Citation - WoS: 7Citation - Scopus: 10A Literature Survey: Is It Necessary To Develop a New Software Development Methodology for Virtual Reality Projects(Graz Univ Technolgoy, inst information Systems Computer Media-iicm, 2017) Güleç, Ulaş; Gulec, Ulas; Yilmaz, Murat; Yılmaz, Murat; Isler, Veysi; Bilgisayar Mühendisliği; Yazılım MühendisliğiSoftware development is a complex human endeavour with high failure rates. Although a variety of software development methodologies have been proposed to improve the software development process, there is no universal model for all software development organizations. Virtual reality (VR) is an emerging trend especially for the gaming industry, which should prepare itself for VR development. The goal of this study is to explore potential software development activities and determine whether designing a new software development methodology for VR projects is an important topic for software development organizations working on VR software development. For this purpose, a literature survey has been completed and 71 academic studies have been examined in detail. This study shows that no work is being conducted in the field of developing a new methodology for VR projects. However, the study does show that there are similar endeavours in the field of human computer interaction (HCI), such as game development methodology.