Now showing items 1-20 of 45

  • A framework for combined recognition of actions and objects 

    Authors:Ar, İlktan; Akgül, Yusuf Sinan
    Publisher and Date:(Springer-Verlag Berlin, 2012)
    This paper proposes a novel approach to recognize actions and objects within the context of each other. Assuming that the different actions involve different objects in image sequences and there is one-to-one relation between object and action type we present a Bayesian network based framework which combines motion patterns and object usage information to recognize actions/objects. More specifically our approach recognizes high-level actions and the related objects without any body-part segmentation ...

  • A Novel Image Steganography Technique based on Similarity of Bits Pairs 

    Authors:Shehzad, Danish; Daǧ, Tamer
    Publisher and Date:(IEEE, 2017)
    Steganography is one of the most important information hiding mechanism which can be used along with cryptography for providing adequate data security. The common Steganographic mediums used are text image audio and video for hiding secret information. In the case of image medium mostly least significant bits of pixels of a cover image are used for hiding secret information. In this paper a new technique based on pairs matching is proposed data bits of the message to be secured are arranged in ...

  • A portable high-productivity approach to program heterogeneous systems 

    Authors:Bozkuş, Zeki; Fraguela, Basilio B.
    Publisher and Date:(IEEE, 2012)
    The exploitation of heterogeneous resources is becoming increasingly important for general purpose computing. Unfortunately heterogeneous systems require much more effort to be programmed than the traditional single or even multi-core computers most programmers are familiar with. Not only new concepts but also new tools with different restrictions must be learned and applied. Additionally many of these approaches are specific to one vendor or device resulting in little portability or rapid ...

  • A Robust Localization Framework to Handle Noisy Measurements in Wireless Sensor Networks 

    Authors:Erten, Cesim; Karataş, Ömer
    Publisher and Date:(IEEE, 2009)
    We construct a robust localization framework to handle noisy measurements in wireless sensor networks. Traditionally many approaches employ the distance information gathered from ranging devices of the sensor nodes to achieve localization. However the measurements of these devices may contain noise both as hardware noise and as environmental noise due to the employment conditions of the network. It Is necessary to provide a general framework that handles such a noise in data and yet still be ...

  • A Software Component Architecture for Adaptive and Predictive Rate Control of Video Streaming 

    Authors:Arsan, Taner; Saydam, Tuncay
    Publisher and Date:(Springer, 2008)
    Quality of Service and Transmission Rate Optimization in live and on-demand video streaming is a very important issue in lossy IP networks. Infrastructure of the Internet exhibits variable bandwidths delays congestions and time-varying packet losses. Because of such attributes video streaming applications should not only have good end-to-end transport layer performance but also a robust rate control optimization mechanisms. This paper gives an overview of video streaming applications and proposal ...

  • Accelerating Brain Simulations on Graphical Processing Units 

    Authors:Kayraklıoğlu, Engin; El-Ghazawi, Tarek A.; Bozkuş, Zeki
    Publisher and Date:(IEEE, 2015)
    NEural Simulation Tool(NEST) is a large scale spiking neuronal network simulator of the brain. In this work we present a CUDA(R) implementation of NEST. We were able to gain a speedup of factor 20 for the computational parts of NEST execution using a different data structure than NEST's default. Our partial implementation shows the potential gains and limitations of such possible port. We discuss possible novel approaches to be able to adapt generic spiking neural network simulators such as NEST ...

  • Action Recognition Using Random Forest Prediction with Combined Pose-based and Motion-based Features 

    Authors:Ar, İlktan; Akgül, Yusuf Sinan
    Publisher and Date:(IEEE, 2013)
    In this paper we propose a novel human action recognition system that uses random forest prediction with statistically combined pose-based and motion-based features. Given a set of training and test image sequences (videos) we first adopt recent techniques that extract low-level features: motion and pose features. Motion-based features which represent motion patterns in the consecutive images are formed by 3D Haar-like features. Pose-based features are obtained by the calculation of scale invariant ...

  • An energy efficient routing algorithm (X-Centric routing) for sensor networks 

    Authors:Ataç, Göktuğ; Daǧ, Tamer
    Publisher and Date:(INT INST Informatics & Systemics, 2011)
    Recent developments in wireless communications and electronics technologies have enabled the progress in low cost sensor networks. Sensor networks differ from traditional networks in several ways such as the severe energy constraints redundant low-rate date and many-to-one flows that the sensor networks require. One of the major challenges facing the design of a routing protocol for Wireless Sensor Networks (WSNs) is to find the most reliable path between the sources and the sink node by considering ...

  • An Integrated Software Architecture for Bandwidth Adaptive Video Streaming 

    Authors:Arsan, Taner
    Publisher and Date:(World Acad Sci Eng & Tech-Waset, 2008)
    Video streaming over lossy IP networks is very important issues due to the heterogeneous structure of networks. Infrastructure of the Internet exhibits variable bandwidths delays congestions and time-varying packet losses. Because of variable attributes of the Internet video streaming applications should not only have a good end-to-end transport performance but also have a robust rate control furthermore multipath rate allocation mechanism. So for providing the video streaming service quality some ...

  • An Analysis for the Use of Compressed Sensing Method in Microwave Imaging 

    One of the most important problems encountered in microwave imaging methods is intensive data processing traffic that occurs when high resolution and real time tracking is desired. Radar signals can be recovered without loss of data with a randomly selected subset of the measurement data by compression sensing (CS) method which has been popular in recent years. For this reason, in this study, the use and capabilities of the CS method were investigated for tracking moving human, and the target ...

  • Analytical Expense Management System 

    Authors:Bozkuş, Zeki; Bisson, Christophe; Arsan, Taner
    Publisher and Date:(IEEE, 2009)
    Although the development of communication technologies (e.g: UMTS ADSL) allowed the elaboration of multiple users' web applications (e.g. information storage) there are still many improvements on many applications to be done and uncovered areas. Expense management systems on web application area are still in their infancy. Expense management software is widely spread in companies and most of time supported by their intranet. These solutions are quite simple as they mainly collect the information ...

  • Biclustering Expression Data Based on Expanding Localized Substructures 

    Authors:Erten, Cesim; Sözdinler, Melih
    Publisher and Date:(Springer-Verlag Berlin, 2009)
    Biclustering gene expression data is the problem of extracting submatrices of genes and conditions exhibiting significant correlation across both the rows and the columns of a data matrix of expression values. We provide a method LEB (Localize-and-Extract Biclusters) which reduces the search space into local neighborhoods within the matrix by first localizing correlated structures. The localization procedure takes its roots from effective use of graph-theoretical methods applied to problems ...

  • Big Data Platform Development with a Domain Specific Language for Telecom Industries 

    This paper introduces a system that offer a special big data analysis platform with Domain Specific Language for telecom industries. This platform has three main parts that suggests a new kind of domain specific system for processing and visualization of large data files for telecom organizations. These parts are Domain Specific Language (DSL) Parallel Processing/Analyzing Platform for Big Data and an Integrated Result Viewer. hi addition to these main parts Distributed File Descriptor (DFD) is ...

  • Channel estimation in underwater cooperative OFDM system with amplify-and-forward relaying 

    Authors:Şenol, Habib; Panayirci, Erdal; Erdoğan, Mustafa; Uysal, Murat
    Publisher and Date:(IEEE, 2012)
    This paper is concerned with a challenging problem of channel estimation for amplify-and-forward cooperative relay based orthogonal frequency division multiplexing (OFDM) systems in the presence of sparse underwater acoustic channels and of the correlative non-Gaussian noise. We exploit the sparse structure of the channel impulse response to improve the performance of the channel estimation algorithm due to the reduced number of taps to be estimated. The resulting novel algorithm initially estimates ...

  • Contraction Blockers for Graphs with Forbidden Induced Paths 

    We consider the following problem: can a certain graph parameter of some given graph be reduced by at least d for some integer d via at most k edge contractions for some given integer k? We examine three graph parameters: the chromatic number clique number and independence number. For each of these graph parameters we show that when d is part of the input this problem is polynomial-time solvable on P-4-free graphs and NP-complete as well as W[1]-hard with parameter d for split graphs. As split ...

  • Cosmic ray intensity variation during a CME 

    The June 6 2000 coronal mass ejection was an exceptional full halo which made it possible to measure cosmic ray (CR) decrease with a simple experimental set-up. Variation in the local secondary cosmic ray density has been investigated by means of gamma rays. The experiment site was located in Istanbul (41.1N 29.0E). CR electrons and slow gamma rays have been eliminated. The CR density has dropped drastically starting on June 8 2000. The counts have been compared with the pre-shock levels and some ...

  • Dark Patches in Clustering 

    Authors:Ishaq, Waqar; Büyükkaya, Eliya
    Publisher and Date:(IEEE, 2017)
    This survey highlights issues in clustering which hinder in achieving optimal solution or generates inconsistent outputs. We called such malignancies as dark patches. We focus on the issues relating to clustering rather than concepts and techniques of clustering. For better insight into the issues of clustering we categorize dark patches into three classes and then compare various clustering methods to analyze distributed datasets with respect to classes of dark patches rather than conventional ...

  • Data-Aided Autoregressive Sparse Channel Tracking for OFDM Systems 

    In order to meet future communication system requirements channel estimation over fast fading and frequency selective channels is crucial. In this paper Space Alternated Generalized Expectation Maximization Maximum a Posteriori (SAGE-MAP) based channel estimation algorithm is proposed for Orthogonal Frequency Division Multiplexing (OFDM) systems for Autoregressive (AR) modeled time-varying sparse channels. Also an initialization algorithm has been developed from the widely used sparse approximation ...

  • Distributed estimation over parallel fading channels with channel estimation error 

    Authors:Şenol, Habib; Tepedelenlioğlu, Cihan
    Publisher and Date:(IEEE, 2008)
    We consider distributed estimation of a source observed by sensors in additive Gaussian noise where the sensors are connected to a fusion center with unknown orthogonal (parallel) flat Rayleigh fading channels. We adopt a two-phase approach of (i) channel estimation with training and (ii) source estimation given the channel estimates where the total power is fixed. We prove that allocating half the total power into training is optimal and show that compared to the perfect channel case a performance ...

  • Distributed estimation with channel estimation error over orthogonal fading channels 

    Authors:Şenol, Habib; Tepedelenlioğlu, Cihan
    Publisher and Date:(IEEE, 2007)
    We study distributed estimation of a source corrupted by an additive Gaussian noise and observed by sensors which are connected to a fusion center with unknown orthogonal (parallel) flat Rayleigh fading channels. The fading communication channels are estimated with training. Subsequently source estimation given the channel estimates and transmitted sensor observations is performed. We consider a setting where the estimated channels are fed-back to the sensors for optimal power allocation which ...