Kurum Yazarı "Gerek, Ömer Nezih" WoS İndeksli Yayınlar Koleksiyonu İçin Listeleme
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An Edge-Sensing Predictor in Wavelet Lifting Structures for Lossless Image Coding
Gerek, Ömer Nezih; Çetin, A. Enis (Springer, 2007)The introduction of lifting implementations for image wavelet decomposition generated possibilities of several applications and several adaptive decomposition variations. The prediction step of a lifting stage constitutes ... -
Editorial for Special Issue on Reproducible Research
Gerek, Ömer Nezih; Boashash, Boualem; Leszczuk, Mikolaj; Tsaftaris, Sotirios A.; Armour, Wes; Wallom, David (Academic Press Inc Elsevier Science, 2018)… -
The Effect of Markov Chain State Size for Synthetic Wind Speed Generation
Hocaoğlu, Fatih Onur; Gerek, Ömer Nezih; Kurban, Mehmet (IEEE, 2008)In this study hourly wind speed time series data of Eskisehir region, Turkey have been used for stochastic generation of wind speed data using the transition matrix approach of the Markov chain process. Previous work on ... -
The effect of model generated solar radiation data usage in hybrid (wind-PV) sizing studies
Hocaoğlu, Fatih Onur; Gerek, Ömer Nezih; Kurban, Mehmet (Pergamon-Elsevier Science LTD, 2009)Wind speed and solar radiation characteristics belonging to past years of a region are the main input parameters in wind-photovoltaic hybrid system (WPHS) sizing studies. Classically, these data are fed to several scenarios ... -
Empirical mode decomposition application for short-term flicker severity
Önal, Yasemin; Gerek, Ömer Nezih; Ece, Doğan Gökhan (Tubitak Scientific & Technical Research Council Turkey, 2016)In this article, an approach based on empirical mode decomposition (EMD) is suggested in order to calculate short-term flicker severity, Pst, in power systems. EMD is a new signal processing method used for the analysis ... -
A fast method for the implementation of common vector approach
Koç, Mehmet; Barkana, Atalay; Gerek, Ömer Nezih (Elsevier Science Inc, 2010)In this paper a novel computation method is proposed to perform the common vector approach (CVA) faster than its conventional implementation in pattern recognition. While conventional CVA calculations perform the classification ... -
Feature extraction, selection and classification code for power line scene recognition
Yetgin, Ömer Emre; Gerek, Ömer Nezih (Elsevier Science BV, 2018)Detection and avoiding of power lines and cables is a critical issue in aircraft flight safety. Despite various improvements in image analysis literature, most of the safety issues depend on visual capabilities of pilots. ... -
Harmonic analysis based hourly solar radiation forecasting model
Fidan, Mehmet; Hocaoğlu, Fatih Onur; Gerek, Ömer Nezih (Inst Engineering Technology-Iet, 2015)In this study, a novel two-step hourly solar radiation modelling procedure is developed. In the first step, hourly solar radiation data of a single day is considered and its periodic Fourier series coefficients are calculated. ... -
A Head-Mounted Sensor-Based Eye Tracking Device: Eye Touch System
Topal, Cihan; Gerek, Ömer Nezih; Doğan, Atakan (Assoc Computing Machinery, 2008)In this study, a new eye tracking system, namely Eye Touch, is introduced. Eye Touch is based on an eyeglasses-like apparatus on which IrDA sensitive sensors and IrDA light sources are mounted. Using inexpensive sensors ... -
Hilbert-Huang Transform Based Approach for Measurement of Voltage Flicker Magnitude and Frequency
Önal, Yasemin; Ece, Doğan Gökhan; Gerek, Ömer Nezih (Taylor & Francis Inc, 2015)Voltage flicker is a non-stationary waveform for which direct spectral analysis is not appropriate. To overcome this difficulty, a Hilbert-Huang transform based technique is proposed here. Hilbert-Huang transform is a new ... -
Hourly Forecasting of Long Term Electric Energy Demand Using Novel Mathematical Models and Neural Networks
Başaran Filik, Ümmühan; Gerek, Ömer Nezih; Kurban, Mehmet (Icic Int, 2011)In this work, hourly forecasting of long term electric energy demand is achieved using mathematical models and Artificial Neural Network (ANN) approaches. Previous works regarding energy demand forecasting either treated ... -
Hourly solar radiation forecasting using optimal coefficient 2-D linear filters and feed-forward neural networks
Hocaoğlu, Fatih Onur; Gerek, Ömer Nezih; Kurban, Mehmet (Pergamon-Elsevier Science LTD, 2008)In this work, the hourly solar radiation data collected during the period August 1, 2005-July 30, 2006 from the solar observation station in Iki Eylul campus area of Eskisehir region are studied. A two-dimensional (2-D) ... -
A Hysteresis Model for Fixed and Sun Tracking Solar PV Power Generation Systems
Başaran Filik, Ümmühan; Filik, Tansu; Gerek, Ömer Nezih (MDPI, 2018)In this study, a new solar photovoltaic (PV) panel output power model is proposed. The model is constructed as a function of ambient temperature and solar radiations for two types (fixed panel and sun tracking panel) of ... -
ICF: An algorithm for large scale classification with conic functions
Çimen, Emre; Öztürk, Gürkan; Gerek, Ömer Nezih (Elsevier Science BV, 2018)Incremental Conic Functions (ICF) algorithm is developed for solving classification problems based on mathematical programming. This algorithm improves previous version of conic function-based classifier construction in ... -
An Image-Processing Based Automated Bacteria Colony Counter
Ateş, Hüseyin; Gerek, Ömer Nezih (IEEE, 2009)This paper presents an image processing based automated counting system to detect the number of bacteria colonies that develop in Petri dishes of microbiology laboratories. The visible colonies represent the initial number ... -
Improved synthetic wind speed generation using modified Mycielski approach
Fidan, Mehmet; Hocaoğlu, Fatih Onur; Gerek, Ömer Nezih (Wiley-Blackwell, 2012)In this paper, novel approaches for wind speed data generation using Mycielski algorithm are developed and presented. To show the accuracy of developed approaches, we used three-year collected wind speed data belonging to ... -
Improving the Efficiency of Predictive Coders Via Adaptive Multiple Predictor Cooperation
Sar, Hüseyin; Topal, Cihan; At, Nuray; Gerek, Ömer Nezih (IEEE, 2013)Due to the popularity of the prediction concept in time series analysis, predictive coding has been an attractive approach, particularly in lossless image compression. Utilization of prediction in time series not only makes ... -
Incremental conic functions algorithm for large scale classification problems
Çimen, Emre; Öztürk, Gürkan; Gerek, Ömer Nezih (Academic Press Inc Elsevier Science, 2018)In order to cope with classification problems involving large datasets, we propose a new mathematical programming algorithm by extending the clustering based polyhedral conic functions approach. Despite the high classification ... -
Induction machine condition monitoring using notch-filtered motor current
Günal, Serkan; Ece, Doğan Gökhan; Gerek, Ömer Nezih (Academic Press LTD- Elsevier Science LTD, 2009)This paper presents a new approach to induction motor condition monitoring using notch-filtered motor current signature analysis (NFMCSA). Unlike most of the previous work utilizing motor current signature analysis (MCSA) ... -
Induction Motor Fault Diagnosis via Current Analysis on Time Domain
Günal, Serkan; Ece, Doğan Gökhan; Gerek, Ömer Nezih (IEEE, 2009)This study proposes a novel approach to induction motor fault diagnosis through motor current analysis. Most of the previous works employing motor current analysis use spectral methods to extract required features for ...