Scopus İndeksli Yayınlar Koleksiyonu
Permanent URI for this collectionhttps://hdl.handle.net/20.500.12416/8651
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Article Diffraction of Waves by a Wedge with Phase Conjugate Faces(Association for Scientific Research, 2011) Umul, Yusuf ZiyaArticle Vessel Segmentation in MRI Using a Variational Image Subtraction Approach(Tubitak Scientific & Technological Research Council Turkey, 2014) Nar, Fatih; Saran, Ayse Nurdan; Saran, MuratVessel segmentation is important for many clinical applications, such as the diagnosis of vascular diseases, the planning of surgery, or the monitoring of the progress of disease. Although various approaches have been proposed to segment vessel structures from 3-dimensional medical images, to the best of our knowledge, there has been no known technique that uses magnetic resonance imaging (MRI) as prior information within the vessel segmentation of magnetic resonance angiography (MRA) or magnetic resonance venography (MRV) images. In this study, we propose a novel method that uses MRI images as an atlas, assuming that the patient has an MRI image in addition to MRA/MRV images. The proposed approach intends to increase vessel segmentation accuracy by using the available MRI image as prior information. We use a rigid mutual information registration of the MRA/MRV to the MRI, which provides subvoxel accurate multimodal image registration. On the other hand, vessel segmentation methods tend to mostly suffer from imaging artifacts, such as Rician noise, radio frequency (RF) inhomogeneity, or partial volume effects that are generated by imaging devices. Therefore, this proposed method aims to extract all of the vascular structures from MRA/MRI or MRV/MRI pairs at the same time, while minimizing the combined effects of noise and RF inhomogeneity. Our method is validated both quantitatively and visually using BrainWeb phantom images and clinical MRI, MRA, and MRV images. Comparison and observer studies are also realized using the BrainWeb database and clinical images. The computation time is markedly reduced by developing a parallel implementation using the Nvidia compute unified device architecture and OpenMP frameworks in order to allow the use of the method in clinical settings.Article Vertical and Horizontal Spillovers from Foreign Direct Investment: Evidence from Malaysian Manufacturing(MIT Press Journals, 2017) Dogan, Ergun; Wong, Koi Nyen; Yap, Michael M.C.Article Singular Dirac Systems in the Sobolev Space(Tubitak Scientific & Technological Research Council Turkey, 2017) Ugurlu, EkinIn this paper we construct Weyl's theory for the singular left-definite Dirac systems. In particular, we prove that there exists at least one solution of the system of equations that lies in the Sobolev space. Moreover, we describe the behavior of the solution belonging to the Sobolev space around the singular point.Article Outputs Bounds for Linear Systems with Repeated Input Signals: Existence, Computation and Application to Vehicle Platooning(Tubitak Scientific & Technological Research Council Turkey, 2018) Schmidt, Klaus Werner; Saglam, Harun BugraThis paper investigates the effect of repeated time-limited input signals on the output excursion of stable, linear time-invariant systems. It is first shown that the maximum norm of the output signal remains bounded if the repeated input signals are separated by a nonzero dwell time. Then a novel method for computing a tight bound on the output signal norm is proposed. The setting of the paper is motivated by a vehicle platooning application, where vehicles repeatedly open/close gaps in order to perform lane changes. The developed method analyzes driving safety by computing a bound on the spacing error between vehicles when performing repeated open/close gap maneuvers.Article Natural Transform Decomposition Method for Solving Fractional-Order Partial Differential Equations with Proportional Delay(MDPI AG, 2019) Baleanu, Dumitru; Shah, Rasool; Arif, Muhammad; Khan, Hassan; Kumam, PoomArticle Inequalities by Means of Generalized Proportional Fractional Integral Operators with Respect to Another Function(MDPI AG, 2019) Rashid, Saima; Noor, Muhammad Aslam; Jarad, Fahd; Kalsoom, Humaira; Chu, Yu-MingArticle Effects of Routing Algorithms on Novel Throughput Improvement of Mobile Ad Hoc Networks(Tubitak Scientific & Technological Research Council Turkey, 2012) Preveze, Barbaros; Safak, AyselA cognitive method called most congested access first (MCAF), minimizing the packet loss ratio and improving the throughput of a multihop mobile WiMAX network, is proposed. MCAF combines both the time division multiple access and the orthogonal frequency division multiple access methods. MCAF additionally uses spectral aid and buffer management methods, which air proposed in this paper, to manage both spectrum. access and packets in the buffers. By using these novel methods, real-time video and voice packet transmission is achieved, data packet loss rate is minimized, and the system throughput per node is improved. Effects of fastest path and ant colony routing algorithms on throughput improvement methods are investigated. It is shown that the fastest path routing algorithm, provides higher throughput values than the ant colony routing algorithm.Article Effects of Calibration Sample Size and Item Bank Size on Ability Estimation in Computerized Adaptive Testing(EDAM, 2015) Weiss, David J.; Şahin, AlperArticle Dualisation of the D = 9 Matter Coupled Supergravity(Institute of Physics Publishing, 2005) Yilmaz, Nejat T.