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Öğe Ağırlıklı geometrik merkez metodu ile pratik PI-PD kontrolör tasarımı(Dicle Üniversitesi Mühendislik Fakültesi, 2016) Özyetkin, M. Mine; Toprak, AbdullahBu çalışmada zaman gecikmeli sistemler için ağırlıklı geometrik merkez metodu kullanılarak PI-PD kontrolör tasarımı yapılmıştır. Bunun için öncelikle verilen bir kontrol sistemini kararlı yapan tüm PD kontrolör parametreleri kararlılık sınır eğrisi metodu kullanılarak hesaplanmıştır. ( d f k ,k ) düzleminde çizilmiş olan bu eğriden yararlanılarak belirli bir ( d f k ,k ) parametre çifti elde edilmiştir. Daha sonra yine kararlılık sınır eğrisi metodu kullanılarak sistemi kararlı yapan tüm PI kontrolör parametreleri ( p i k ,k ) düzleminde çizilmiş ve bu kararlılık bölgesi içerisinden ağırlıklı geometrik merkez metodu vasıtasıyla belirli bir ( p i k ,k ) parametre çifti elde edilmiştir. ( d f k ,k ) ve ( p i k ,k ) düzlemlerinde çizilen kararlılık sınır eğrilerden yaralanarak, sistemi kararlı yapan tüm PI-PD kontrolör parametre değerleri hesaplanabilmektedir. Ancak bu bölgeler içerisinden sistem performansını en iyi şekilde sağlayabilecek parametrelerin seçimi önemli bir sorundur. Ağırlıklı geometrik merkez metodu bu soruna oldukça pratik ve kullanışlı bir çözüm sunmaktadır. Metotla ilgili bazı örnekler verilmiş ve birim basamak cevapları incelenerek kullanılan metodun performans analizi yapılmıştır.Öğe Angiograph image restoration with the use of rule base fuzzy 2D Kalman filter(Pergamon-Elsevier Science Ltd, 2008) Toprak, Abdullah; Gueler, InanRecursive estimation techniques such as Kalman filter have been used for a long time in image restoration. The aim of this paper is restoration of the images, which are heavy corrupted with the mix of Gaussian and impulse noises, by using novel rule base fuzzy 2D Kalman filter (RBFK). Rule base fuzzy 2D Kalman filter has been utilized for restoration of image which is contaminated with random noises. In the first step of the study, the noisy images were converted to stack which includes several stationary images in order to apply Kalman filter. The experiments which are indicated that rule based fuzzy 2D Kalman filter is one of the best techniques to remove the mix of Gaussian and impulse noises. Altough, Kalman Filter is used in motion images, in this study, it was applied to the stationary images which were duplicated many times to obtain stack. (C) 2007 Elsevier Ltd. All rights reserved.Öğe Bulanık SMRGT yönteminin pratik uygulamaları(Dicle Üniversitesi Mühendislik Fakültesi, 2017) Toprak, Abdullah; Aykaç, Zeynep; Toprak, Z. FuatBulanık modellemede, üyelik fonksiyonları ve bulanık kuralların uygun bir şekilde belirlenmesi, denemeyanılma sürecinin kısa tutulabilmesi ve modelin başarısı açısından birinci derecede önemlidir. Gerek üyelik fonksiyonlarının belirlenmesine gerek kuralların atanmasına ilişkin literatürde çeşitli yaklaşımlara rastlamak mümkündür (Genetik Algoritma, Yapay Sinir Ağları, Kalman Filtresi, çeşitli istatistiksel ve grafiksel yaklaşımlar gibi). Fakat bu algoritmalar genellikle, üyelik fonksiyonları ve bulanık kuralların belirlenmesi için ayrı ayrı geliştirilmiştir. Bu yöntemlerin bir kısmı ayrıca paket programları ve geniş zaman ve işlem hacmini gerektirirken bir kısmı ise deneme-yanılma yönteminden tümü ile kurtaracak kadar iyi sonuç verememektedir. Bu çalışmada ise hem üyelik fonksiyonlarının (üçgen/trapez) belirlenmesinde hem de bulanık kuralların atanmasında sentroid durulaştırma yöntemi ile kullanılabilecek SMRGT adında literatürde yeni olan bir yaklaşımın iki pratik uygulaması sunulmaktadır. Uygulama sonucunda, yöntemin başarılı olduğu görülmüştür.Öğe Cep telefonlarının yaydığı radyasyonunun testis üzerine etkilerinin elektron mikroskobik olarak değerlendirilmesi(2014) Toprak, AbdullahÖZET Cep Telefonlarının Yaydığı Radyasyonunun Testis Üzerine Etkilerinin Elektromikroskobik Olarak Değerlendirilmesi Abdullah TOPRAK Bu çalışmada cep telefonlarından yayınlanan mikrodalga radyasyonunun farelerin testis dokusu üzerine etkisinin araştırılması amaçlanmıştır. 36 Wistar albino rat dört gruba bölündü. Bunlar, sham uygulaması yapılan kontrol grubu erkek (n=6) ve dişi (n=12) ile deney grubu erkek (n=6) ve dişi (n=12) şeklindeydi. Fareler uygulama boyunca plexiglas kafeslere konuldu ve cep telefonları kafeslerin 0,5 cm altına yerleştirildi. Tüm deney gruplarında cep telefonları, iki saatlik uygulama periyodu süresince her biri birer dakikalık üç kez konuşma moduna getirildi. Erkek farelerde radyofrekans radyasyonu (RFR) ve sham uygulamaları bir ay devam etti.. Sham (Kontrol) grubundaki hayvanlar radyofrekans uygulamaları dışında aynı deney şartlarına maruz bırakıldılar (cep telefonları kapatıldı). Bu araştırmada yer alan ve uygulamaya tabi tutulan dişi farelerin erkek yavrularının testislerinde bir değişimin sözkonusu olup olmadığını tespit edilebilmesi amacıyla yavru deney ve kontrol grupları oluşturuldu. Son uygulamadan hemen sonra tüm fareler intraperitonal yolla letal öldürücü dozdaki pentobarbital ile öldürüldü. Tüm erkek erişkin ve yavru ratların testis dokuları histopatolojik olarak ışık ve elektron mikroskobu ile incelendi. Yapılan inceleme sonunda, deney ve kontrol grubu arasında histopatolojik olarak anlamlı farklılık gözlenmedi. Deney ve sham (kontrol) grubu farelerin rektal sıcaklıkları arasında anlamlı farklılık bulunmadı (P>0,05). Deney grubu farelerda spesifik absorblanma oranı (SAR) değeri 0,155 W/kg olarak bulundu. Anahtar Kelimeler : 1- Cep Telefonu 2- Mikrodalga Radyasyonu 3- Testis 4- Radyo Frekans ABSTRACT The Electron Microscopical Evaluation of Cell Phone Exposure on Rat TestesTissue Abdullah TOPRAK The present study aimed to investigate the effects of microwaves emitted by cellular phones on testis (male rats) tissues of rats. Thirtysix Wistar albino rats were divided into four groups, male (n=6) and female sham-exposed groups (n=12) and male (n=6) and female experimental groups (n=12). The rats were confined in plexiglas cages and cellular phones were placed 0,5 cm under the cages. In all the experimental groups, phones were turned to the speech position for 1 min. Three times a day during an exposure periad of 2 h. In male rats, Radiofrequency, Radiation (RFR) and sham exposures were continued for 1 month.. The animals in the sham groups were handled and treated identically to the exposed groups, except that no RFR was emitted from the cellular phones. The reason of female exposure group is to observe the effect of radiation emitted from cellular phones on the testes of male of springs. Immediately after the last exposure, all the rats were killed with alethal dose of pentobarbital introperitoneally. All adult male and male ofsprings rats testis tissue were examined with a light microscope and electron microscope. After the examination, no significant differences were observed between sham (control) and experimental groups histopathologically. It was not found significant differences between rectal temperatures of rats in the sham and experimental groups (P>0,05). The spesific absorbtion rate (SAR) was measured as to be 0,155 W/kg for the experimental groups. Key Words : 1- Cellular Phone 2- Microwave Radiations 3- Testes 4- Radiofrequency ^1Zv«J^OHÖğe Extreme learning machine (ELM)-based classification of benign and malignant cells in breast cancer(International Scientific Information, Inc., 2018) Toprak, AbdullahBackground: Breast cancer is one of the most common cancer types in the world and is a serious threat to health. This type of cancer is complex; it is a hereditary disease and does not result from a single cause. The diagnosis of cancer starts with a biopsy. Various methods are used to detect and recognize cancer cells, from microscopic images and mammography to ultrasonography and magnetic resonance images (MRI). Material/Methods: Detection and characterization of benign and malignant cells by image-processing-based segmentation for breast cancer diagnosis is important for early diagnosis. In the present study, Extreme Learning Machine (ELM) classification was performed for 9 features based on image segmentation in the Breast Cancer Wisconsin (Diagnostic) data set in the UC Irvine Machine Learning Repository database. Results: The results obtained with the developed method were compared with the results of other machine learning methods (Naive Bayes, Support Vector Machine, and Artificial Neural Network) and it showed the highest performance, with a result of 98.99%. Conclusions: It was found that both accuracy and speed were good. We present a method that can be applied in cell morphology detection and classification in automated systems that classify by computer-aided mammogram image features.Öğe Impulse noise reduction in medical images with the use of switch mode fuzzy adaptive median filter(Academic Press Inc Elsevier Science, 2007) Toprak, Abdullah; Gueler, InanIn this paper, a novel fuzzy adaptive median filter is presented for the noise reduction in MR images corrupted with heavy impulse (salt&pepper) noise. We propose a switch mode fuzzy adaptive median filter (SMFAMF) for removing highly corrupted salt&pepper noise without destroying edges and details in the image. The SMFAMF filter is an improved version of adaptive median filter (AMF) in order to reduce additive impulse noise in the images. The proposed filter can preserve details in the images better than AMF while suppressing additive salt&pepper or impulse type noises. In this paper, we placed our preference on bell-shaped membership function with adaptive parameters instead of triangular membership function without variable coefficients in order to observe better results. Experiments with the magnetic resonance (MR) image from healthy subject, an MR image having the opaque material, and an MR image having disease demonstrate the mean square error (MSE), root mean square error (RMSE), signal-to-noise ratio (SNR), and peak signal-to-noise ratio (PSNR) of the proposed method. The results show that the proposed method can be useful for MR images with impulse type noises. (c) 2006 Elsevier Inc. All rights reserved.Öğe Quantum noise suppression in X-ray images using fuzzy 2-D Wiener filter(Springer, 2007) Toprak, AbdullahThe noisy images are caused by decreasing quantity of the produced X-ray due to the deformation of the X-ray tube's anode. While obtaining the image from low quantity X-ray, shot noise or quantum noise occurs, and this decreases the quality of the image. The aim of this study is to define the novel method called as Fuzzy 2-D Weiner filter (FWF-2D), which suppresses the shot noise from noisy image by avoiding any harm to the image details. With this filtering technique, it is possible to preserve the sharp-edge and the details of the image without any damage during suppressing the noise from images. FWF-2D is one of the best techniques to suppress the corrupted quantum noises due to damaged X-ray tube. The fuzzy rules used in this filter are aimed to distinguish noise pixels from image ones, and the Wiener Filter is working to remove noise pixels distinguished by these fuzzy rules. It is then possible to obtain clean images from damaged X-ray tubes by using FWF-2D technique.Öğe Reduction in impulse noise in digital images through a new adaptive artificial neural network model(Springer, 2015) Budak, Cafer; Turk, Mustafa; Toprak, AbdullahIn this paper, an adaptive artificial neural network model is developed in order to restore severely corrupted images. The proposed new and effective impulse noise reduction filter is named as adaptive neural network models with an algorithm based on artificial neural networks. Networks trained at different noise intensities get activated according to the intensity of the noise and estimate the most suitable neighboring pixel that can replace the corrupted pixel. The proposed algorithm reduces impulse noise effectively while also protecting the details. Experimental results show that the proposed algorithm performs better compared with other traditional filters.Öğe Removal of impulse noise in digital images with naive Bayes classifier method(Tubitak Scientific & Technological Research Council Turkey, 2016) Budak, Cafer; Turk, Mustafa; Toprak, AbdullahA new method has been presented in this paper to remove randomly formed impulse noise in digital images. This method is one of the favorite learning approaches of the Bayes learning method and is frequently called the na ve Bayes classifier. It has especially been used more frequently in recent times in the field of signal processing. Prior to restoration of the noisy pixels of the image as is done here, the image is first separated into pieces, and then an associated learning set is formed for each piece using the noise-free pixels. These learning sets that are different for each piece are used in order to estimate the pixel that will replace the noisy one. The proposed method is both simple and easy to apply. Our comprehensive experimental studies show that our proposed method outperforms other filters that are very popular in the literature.Öğe Removal of impulse noise in digital images with na¨ıve Bayes classifier method(2016) Budak, Cafer; Toprak, Abdullah; Türk, MustafaA new method has been presented in this paper to remove randomly formed impulse noise in digital images. This method is one of the favorite learning approaches of the Bayes learning method and is frequently called the na¨ıve Bayes classifier. It has especially been used more frequently in recent times in the field of signal processing. Prior to restoration of the noisy pixels of the image as is done here, the image is first separated into pieces, and then an associated learning set is formed for each piece using the noise-free pixels. These learning sets that are different for each piece are used in order to estimate the pixel that will replace the noisy one. The proposed method is both simple and easy to apply. Our comprehensive experimental studies show that our proposed method outperforms other filters that are very popular in the literature.Öğe Suppression of impulse noise in medical images with the use of fuzzy adaptive median filter(2006) Toprak, Abdullah; Güler, İnan; 0000-0002-5058-0846A new rule based fuzzy filter for removal of highly impulse noise, called Rule Based Fuzzy Adaptive Median (RBFAM) Filter, is aimed to be discussed in this paper. The RBFAM filter is an improved version of Adaptive Median Filter (AMF) and is presented in the aim of noise reduction of images corrupted with additive impulse noise. The filter has three stages. Two of those stages are fuzzy rule based and last stage is based on standard median and adaptive median filter. The proposed filter can preserve image details better then AMF while suppressing additive salt&pepper or impulse type noise. In this paper, we placed our preference on bell-shaped membership function instead of triangular membership function in order to observe better results. Experimental results indicates that the proposed filter is improvable with increased fuzzy rules to reduce more noise corrupted images and to remove salt and pepper noise in a more effective way than what AMF filter does.Öğe Suppression of impulse noise in MR images using artificial intelligent based neuro-fuzzy adaptive median filter(Academic Press Inc Elsevier Science, 2008) Toprak, Abdullah; Ozerdem, Mehmet Sirac; Guler, InanThis paper presents a new artificial intelligent based neuro-fuzzy rule base adaptive median filter for removing highly impulse noise. Since the filter is rule base, it is called neuro-fuzzy rule base adaptive median (NFRBAM) filter. The NFRBAM filter is an improved version of switch mode fuzzy adaptive median filter (SMFAMF) and is presented for the purpose of noise reduction of images corrupted with additive impulse noise. The NFRBAM filter consists of a decision unit and three different types of filters. In the decision unit, the noisy input image is directed to the proper filter with respect to the noise density. Neuro-fuzzy rule based approach is used in both decision and filtering parts. In artificial neural network, multi layer perceptron (MLP) architecture with backpropagation (BP) algorithm is used for noise detection and removing highly impulse noise corrupted MR images. In fuzzy logic, bell-shaped membership function is employed in order to obtain better results. Experimental results indicate that the proposed filter is improvable with the increased fuzzy rules to reduce more noise corrupted images and preserve image details more than SMFAMF. (c) 2007 Elsevier Inc. All rights reserved.
