Erkan Deniz

Prof. Dr. Erkan Deniz

Electrical Electronics Engineering, Fırat University, Elazığ, Turkey (Türkiye)
orcid

Research Focus & Metrics

Academic Career Length

16Years (2011-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 May 2016 in Measurement
Verified
Journal Article
Closed access
Erkan DenizErkan Deniz
Erkan Deniz
OAOmur Aydogmus
Omur Aydogmus
ZAZafer Aydogmus
Zafer Aydogmus

26 April 2016 in Neural Computing and Applications
Verified
Journal Article
Closed access
PDF file
Erkan DenizErkan Deniz
Erkan Deniz

4 January 2023 in Diagnostics
Verified
Journal Article
Open access
PDF file
SOSalih Taha Alperen Ozcelik
Salih Taha Alperen Ozcelik
HAKAN UYANIKHAKAN UYANIK
HAKAN UYANIK
Erkan DenizErkan Deniz
Erkan Deniz
AŞAbdulkadir Şengür
Abdulkadir Şengür
Blood pressure is the pressure exerted by the blood in the veins against the walls of the veins. If this value is above normal levels, it is known as high blood pressure (HBP) or hypertension (HPT). This health problem which often referred to as the “silent killer” reduces the quality of life and causes severe damage to many body parts in various ways. Besides, its mortality rate is very high. Hence, rapid and effective diagnosis of this health problem is crucial. In this study, an automatic diagnosis of HPT has been proposed using ballistocardiography (BCG) signals. The BCG signals were transformed to the time-frequency domain using the spectrogram method. While creating the spectrogram images, parameters such as window type, window length, overlapping rate, and fast Fourier transform size were adjusted. Then, these images were classified using ConvMixer architecture, similar to vision transformers (ViT) and multi-layer perceptron (MLP)-mixer structures, which have attracted a lot of attention. Its performance was compared with classical architectures such as ResNet18 and ResNet50. The results obtained showed that the ConvMixer structure gave very successful results and a very short operation time. Our proposed model has obtained an accuracy of 98.14%, 98.79%, and 97.69% for the ResNet18, ResNet50, and ConvMixer architectures, respectively. In addition, it has been observed that the processing time of the ConvMixer architecture is relatively short compared to these two architectures.

8 August 2023 in Sensors
Verified
Journal Article
Open access
PDF file
OAOrhan Atila
Orhan Atila
Erkan DenizErkan Deniz
Erkan Deniz
AAAli Ari
Ali Ari
AŞAbdulkadir Şengür
Abdulkadir Şengür
Subrata ChakrabortySubrata Chakraborty
Subrata Chakraborty
U Rajendra AcharyaU Rajendra Acharya
U Rajendra Acharya
Anxiety, learning disabilities, and depression are the symptoms of attention deficit hyperactivity disorder (ADHD), an isogenous pattern of hyperactivity, impulsivity, and inattention. For the early diagnosis of ADHD, electroencephalogram (EEG) signals are widely used. However, the direct analysis of an EEG is highly challenging as it is time-consuming, nonlinear, and nonstationary in nature. Thus, in this paper, a novel approach (LSGP-USFNet) is developed based on the patterns obtained from Ulam’s spiral and Sophia Germain’s prime numbers. The EEG signals are initially filtered to remove the noise and segmented with a non-overlapping sliding window of a length of 512 samples. Then, a time–frequency analysis approach, namely continuous wavelet transform, is applied to each channel of the segmented EEG signal to interpret it in the time and frequency domain. The obtained time–frequency representation is saved as a time–frequency image, and a non-overlapping n × n sliding window is applied to this image for patch extraction. An n × n Ulam’s spiral is localized on each patch, and the gray levels are acquired from this patch as features where Sophie Germain’s primes are located in Ulam’s spiral. All gray tones from all patches are concatenated to construct the features for ADHD and normal classes. A gray tone selection algorithm, namely ReliefF, is employed on the representative features to acquire the final most important gray tones. The support vector machine classifier is used with a 10-fold cross-validation criteria. Our proposed approach, LSGP-USFNet, was developed using a publicly available dataset and obtained an accuracy of 97.46% in detecting ADHD automatically. Our generated model is ready to be validated using a bigger database and it can also be used to detect other children’s neurological disorders.

5 April 2014 in Arabian Journal for Science and Engineering
Verified
Journal Article
Closed access
PDF file
OAOmur Aydogmus
Omur Aydogmus
Erkan DenizErkan Deniz
Erkan Deniz
KKKorhan Kayisli
Korhan Kayisli

1 March 2015
Verified
Conference Paper
Closed access
Erkan DenizErkan Deniz
Erkan Deniz
OAOmur Aydogmus
Omur Aydogmus
ZAZafer Aydogmus
Zafer Aydogmus
Selective harmonic elimination (SHE) is a well-known PWM technique applied voltage source inverters (VSI) to control fundamental voltage and eliminate chosen harmonics. This technique requires the determination of optimum switching angles by solving the nonlinear equation set and a look-up table stored the switching times in a real-time application. This paper presents a hybrid genetic algorithm (GA) to optimize offline of optimum 11-switching angles for three-phase two-level inverter. In addition, the paper proposes two Artificial Neural Networks (ANN) based solution. The first ANN was trained by the data obtained from GA to calculate the switching angles without using a look-up table. Second ANN was trained by using these switching angles to generate PWM signals. GA and ANN are performed by using MATLAB environment. The ANN-based SHEPWM was designed to obtain inverter output voltage which has a bipolar waveform with quarter-wave symmetry. The waveforms of inverter output voltage and load current are analyzed with FFT for a RL load.