Now showing items 21-40 of 71

    • Dual Kalman Filter based State-Parameter Estimation in Linear Lung Models 

      Akan, Aydın; Saatçı, Esra (Springer, 233 Spring Street, New York, Ny 10013, United States, 2009)
      Time-domain approach to inverse modeling of respiratory system requires estimation of the parameters from the noisy observation. In this work, states and parameters of the linear lung models are estimated simultaneously ...
    • Application of Stockwell Coherence To Prediction Of Alertness Under Anaesthesia 

      Gürkan, Güray; Akan, Aydın; Demiralp, Tamer (Brno Univ Technology Vut Press, Purkynova 118, Brno 61200, Czech Republic, 2010)
      In this paper, we represent an application of Stockwell Coherence to scalp EEG signals under anesthesia. By the analysis of overlapping, stationary data segments, we obtained the time-varying Stockwell coherence, which ...
    • Inverse Modeling of Respiratory System during Noninvasive Ventilation by Maximum Likelihood Estimation 

      Saatçı, Esra; Akan, Aydın (Hindawi Publishing Corporation, 410 Park Avenue, 15Th Floor, #287 Pmb, New York, Ny 10022 Usa, 2010)
      We propose a procedure to estimate the model parameters of presented nonlinear Resistance-Capacitance (RC) and the widely used linear Resistance-Inductance-Capacitance (RIC) models of the respiratory system by Maximum ...
    • Radiation Characteristics Of A Coaxial Waveguide With Opposing Dielectric Filled Grooves 

      Hacıvelioğlu, Feray; Uzgören, Gökhan; Büyükaksoy, Alinur (Inst Engineering Technology-Iet, Michael Faraday House Six Hills Way Stevenage, Hertford Sg1 2Ay, England, 2010-01)
      The purpose of the present study is to provide a rigorous analysis to the coaxial waveguide with two opposing grooves in the outer and inner cylinders with different depths and filled with different dielectric materials. ...
    • Respiratory Parameter Estimation In Non-İnvasive Ventilation Based On Generalized Gaussian Noise Models 

      Saatçı, Esra; Akan, Aydın (Elsevier Science Bv, Po Box 211, 1000 Ae Amsterdam, Netherlands, 2010-02)
      Modeling of respiratory system under non-invasive ventilation by using measured respiratory signals is of great interest in respiratory mechanics research area. Statistical processing techniques in the time-domain may be ...
    • Estimation Of The Respiratory System Parameters 

      Sert, Görkem; Saatçı, Esra; Gürkan, Güray; Akan, Aydın (European Assoc Signal Speech & Image Processing-Eurasip, Po Box 74251, Kessariani, 151 10, Greece, 2011)
      In clinical respiratory studies, resistance and the lung compliance are two important respiratory parameters that are often measured by physicians. In this work, Respiratory signals (mask pressure, airway flow, and lung ...
    • Posterior Cramer-Rao Lower Bounds for Dual Kalman estimation 

      Saatçı, Esra; Akan, Aydın (Academic Press inc Elsevier Science, 525 B St, Ste 1900, San Diego, Ca 92101-4495 USA, 2012-01)
      We present the Posterior Cramer-Rao Lower Bounds (PCRLB) for the dual Kalman filter estimation where the parameters are assumed to be time-invariant and stationary random variables. Relations between the PCRLB, the states, ...
    • Bayesian Compressive Sensing for Ultra-Wideband Channel Models 

      Özgör, Mehmet; Erküçük, Serhat; Çırpan, Hakan Ali (Ieee, 345 E 47Th St, New York, Ny 10017 Usa, 2012-07-03)
      Considering the sparse structure of ultra-wideband (UWB) channels, compressive sensing (CS) is suitable for UWB channel estimation. Among various implementations of CS, the inclusion of Bayesian framework has shown potential ...
    • High-Performance Mimo Ofdm Wireless Systems With Generalized Prefix 

      Acar, Yusuf; Yıldız, Hakan; Cooklev, Todor; Doğan, Hakan (IEEE, 345 E 47Th St, New York, Ny 10017 Usa, 2013)
      Consumers require increasing data rates and therefore it is important to develop techniques that increase the spectrum efficiency. MIMO OFDM is a fundamental technology for high data rate wireless systems. Correlation among ...
    • Performance Improvement for Correlated 4x4 MIMO-OFDM Systems by Generalized Prefix Approach 

      Acar, Yusuf; Cooklev, Todor; Doğan, Hakan; Yıldız, Hakan (IEEE, 345 E 47Th St, New York, Ny 10017 Usa, 2013)
      Antenna correlation limits the multiplexing gain achieved by practical MIMO-OFDM systems and degrades the performance significantly. Recently, investigations are focused to reduce the antenna correlation by the designing ...
    • A New Method for Doppler Centroid Estimation Based on Block Processing 

      Kartal, Mesut; Tunçay, Pelin (IEEE, 345 E 47Th St, New York, Ny 10017 Usa, 2013)
      Doppler centroid frequency is an important parameter for Synthetic Aperture Radar signal processing, which is used to design a proper matched filter in azimuth domain. Doppler centroid is estimated from the received data. ...
    • TEM Wave Scattering by a Step Discontinuity on the Outer Wall of a Coaxial Waveguide 

      Akşimşek, Sinan; Çınar, Gökhan; Nilsson, Börje; Nordebo, Sven (2013-08)
      In this paper, the propagation of TEM waves along a coaxial waveguide with a step discontinuity on its outer wall is investigated rigorously by applying the direct Fourier transform and reducing the problem into the solution ...
    • Three-Dimensional Fully Interlaced Woven Preforms for Composites 

      Bilişik, Nedim Erman; Bilişik, Havva Esra; Bilişik, Abdulkadir; Şahbaz Karaduman, Nesrin (Sage Publications Ltd, 1 Olivers Yard, 55 City Road, London Ec1Y 1Sp, England, 2013-11)
      The aim of this study was to develop three-dimensional (3D) fully interlaced and semi-interlaced representative woven preform structures and to understand the effects of weave pattern and number of layers on 3D woven ...
    • Iterative Channel Estimation For Spatial Modulation Systems Over Fast Fading Channels 

      Acar, Yusuf; Doğan, Hakan; Panayırcı, Erdal (IEEE, 345 E 47Th St, New York, Ny 10017 Usa, 2014)
      Spatial Modulation (SM) based on the use of antenna indices to transmit information in addition to the conventional signal constellations has been recently proposed to solve practical problems encountered in MIMO systems. ...
    • Analysis of brain connectivity changes after propofol injection by generalized partial directed coherence 

      Gürkan, Güray; Akan, Aydın; Özkan Seyhan, Tülay (Academic Press Inc Elsevier Science, 525 B St, Ste 1900, San Diego, Ca 92101-4495 Usa, 2014)
      In this paper we present a method for the analysis of multichannel EEG by using Generalized Partial Directed Coherence (gPDC) to extract cortical connectivity changes under anesthesia. 15 channel EEG data were recorded ...
    • Channel Estimation for SM Systems over Time-Varying Rayleigh Fading Channels 

      Acar, Yusuf; Doğan, Hakan; Panayırcı, Erdal (IEEE, 345 E 47Th St, New York, Ny 10017 Usa, 2014)
      This paper is concerned with the challenging and timely problem of channel estimation for spatial modulated systems in the presence of time varying channels. Recently, estimation of channel state information for SM systems ...
    • Generalized Prefix Approach for Alamouti Coded OFDM Systems over Gaussian Channels Correlated in Space 

      Acar, Yusuf; Yıldız, Hakan; Cooklev, Todor; Doğan, Hakan (IEEE, 345 E 47Th St, New York, Ny 10017 Usa, 2014)
      In this ivorkt, generalized frelix (GP) lbr space time block coded orthogonal frequency division multiplexing (STBC-OFDM) systems is considered in the presence of correlated channel. The 2x2 STBC case, in practice, lead ...
    • Three- dimensional circular various weave patterns in woven preform structures 

      Bilişik, Kadir; Şahbaz Karaduman, Nesrin; Bilişik, Nedim Erman; Bilişik, Havva Esra (Sage Publications Ltd, 1 Olivers Yard, 55 City Road, London Ec1Y 1Sp, England, 2014-04)
      The aim of this study was to develop three-dimensional (3D) fully interlaced representative circular woven preform structures and to understand the effects of weave pattern and number of layers on 3D circular woven structures. ...
    • Generalised prefix for space-time block-coded orthogonal frequency division multiplexing wireless systems over correlated multiple-input multiple-output channels 

      Yıldız, Hakan; Acar, Yusuf; Cooklev, Todor; Doğan, Hakan (Inst Engineering Technology-Iet, Michael Faraday House Sıx Hılls Way Stevenage, Hertford Sg1 2Ay, England, 2014-06-12)
      Space-time block coding (STBC) orthogonal frequency division multiplexing (OFDM) is known to improve the reliability of broadband communication over wireless links. However, this technique suffers from a performance loss ...
    • Pilot symbol assisted channel estimation for 4x4 space time block coded spatial modulation systems 

      Acar, Yusuf; Doğan, Hakan; Panayırcı, Erdal (IEEE, 345 E 47th St, New York, Ny 10017 USA, 2015)
      Recently, spatial modulation (SM) and space-time block coding (STBC) are combined to take advantage of the benefits of both while avoiding their drawbacks for multiple-input and multiple-output (MIMO) systems. The pioneering ...