Electrical - Electronic Engineering / Elektrik - Elektronik Mühendisliği

Permanent URI for this collectionhttps://hdl.handle.net/11147/11

Browse

Filters

2014 - 20203

Settings

Author: search.filters.author.Karakuş, OktayScopus Q: search.filters.scopusQuartile.Q2

Search Results

Now showing 1 - 3 of 3
  • Article
    Citation - WoS: 22
    Citation - Scopus: 27
    Modelling Impulsive Noise in Indoor Powerline Communication Systems
    (Springer Verlag, 2020) Karakuş, Oktay; Kuruoğlu, Ercan E.; Altınkaya, Mustafa Aziz
    Powerline communication (PLC) is an emerging technology that has an important role in smart grid systems. Due to making use of existing transmission lines for communication purposes, PLC systems are subject to various noise effects. Among those, the most challenging one is the impulsive noise compared to the background and narrowband noise. In this paper, we present a comparative study on modelling the impulsive noise amplitude in indoor PLC systems by utilising several impulsive distributions. In particular, as candidate distributions, we use the symmetric alpha-Stable (S alpha S), generalised Gaussian, Bernoulli Gaussian and Student's t distribution families as well as the Middleton Class A distribution, which dominates the literature as the impulsive noise model for PLC systems. Real indoor PLC system noise measurements are investigated for the simulation studies, which show that the S alpha S distribution achieves the best modelling success when compared to the other families in terms of the statistical error criteria, especially for the tail characteristics of the measured data sets.
  • Article
    Citation - WoS: 103
    Citation - Scopus: 122
    One-Day Ahead Wind Speed/Power Prediction Based on Polynomial Autoregressive Model
    (Institution of Engineering and Technology, 2017) Karakuş, Oktay; Kuruoğlu, Ercan Engin; Altınkaya, Mustafa Aziz
    Wind has been one of the popular renewable energy generation methods in the last decades. Foreknowledge of power to be generated from wind is crucial especially for planning and storing the power. It is evident in various experimental data that wind speed time series has non-linear characteristics. It has been reported in the literature that nonlinear prediction methods such as artificial neural network (ANN) and adaptive neuro fuzzy inference system (ANFIS) perform better than linear autoregressive (AR) and AR moving average models. Polynomial AR (PAR) models, despite being non-linear, are simpler to implement when compared with other non-linear AR models due to their linear-in-the-parameters property. In this study, a PAR model is used for one-day ahead wind speed prediction by using the past hourly average wind speed measurements of Ceşme and Bandon and performance comparison studies between PAR and ANN-ANFIS models are performed. In addition, wind power data which was published for Global Energy Forecasting Competition 2012 has been used to make power predictions. Despite having lower number of model parameters, PAR models outperform all other models for both of the locations in speed predictions as well as in power predictions when the prediction horizon is longer than 12 h.
  • Article
    Citation - WoS: 3
    Citation - Scopus: 4
    Perceptual Quality Evaluation of Asymmetric Stereo Video Coding for Efficient 3d Rate Scaling
    (Türkiye Klinikleri Journal of Medical Sciences, 2014) Özbek, Nükhet; Ertan, Gizem; Karakuş, Oktay
    In 3D perception, the binocular suppression of the human vision, perceiving high quality 3D video in the case of a view in higher quality, can be exploited in asymmetric stereo video coding for efficient 3D rate scaling. Hence, the best stereo rate-visual distortion performance may be gained by asymmetric coding, which is the reduction of the spatial and/or quantization resolution of the low-quality view, while keeping the high-quality view in full resolution. However, how to determine the level of asymmetry and what type of scaling should be chosen are still in question. In this work, we try to assess the overall performance of the scalability options with several test contents. The test videos are encoded at critical bitrates with symmetric options and spatial or signal-to-noise ratio (SNR) asymmetric coding, and are subjectively evaluated in a stereo-polarized projection 3D display system. Two different types of evaluation methodologies are used: the Double-Stimulus Continuous-Quality Scale (DSCQS) and Subjective Evaluation of Stereo Video Quality (SESVIQ). Dense visual tests show that the spatial scaling is generally inferior when compared to SNR scaling, except that high motion scenes and symmetric SNR are more preferable for a higher bitrate. The characteristics of the video content should be taken into consideration for efficient stereo rate scaling.