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Article Citation - WoS: 7Citation - Scopus: 10Comparison of Three Different Learning Methods of Multilayer Perceptron Neural Network for Wind Speed Forecasting(Gazi Univ, 2021) Bulut, Mehmet; Tora, Hakan; Buaisha, Dr.magdiIn the world, electric power is the highest need for high prosperity and comfortable living standards. The security of energy supply is an essential concept in national energy management. Therefore, ensuring the security of electricity supply requires accurate estimates of electricity demand. The share of electricity generation from renewables is significantly growing in the world. This kind of energy types are dependent on weather conditions as the wind and solar energies. There are two vital requirements to locate and measure specific systems to utilize wind power: modelling and forecasting of the wind velocity. To this end, using only 4 years of measured meteorological data, the present research attempts to estimate the related speed of wind within the Libyan Mediterranean coast with the help of ANN (artificial neural networking) with three different learning algorithms, which are Levenberg-Marquardt, Bayesian Regularization and Scaled Conjugate Gradient. Conclusions reached in this study show that wind speed can be estimated within acceptable limits using a limited set of meteorological data. In the results obtained, it was seen that the SCG algorithm gave better results in tests in this study with less data.Conference Object Naturalness Analysis of the Speech Synthesized by a Tts Card(Ieee, 2016) Tora, Hakan; Uslu, BaranIt is known that the performance of a developed text-to-speech (TTS) synthesis system is assessed by subjective tests. These assessments are usually based on the intelligibility and naturalness of the synthesized speech. In this study, an investigation on relating these subjective test results, thus the naturalness of the synthesized speech, to which acoustic features is accomplished. Consequently the features which will increase the performance while synthesizing the speech are determined. Our work is focused especially on the pitch frequency and energy parameters.Conference Object Citation - WoS: 1THE USE OF CUMULANTS FOR VOICED-UNVOICED SEGMENTS IDENTIFICATION IN SPEECH SIGNALS(Ieee, 2014) Uslu, Baran; Tora, HakanIn this study, voiced-unvoiced classification performance of Turkish sounds using skewness and kurtosis is examined. The analyses show that higher order cumulants can be employed as a feature in voiced-unvoiced classification that is vital in speech processing applications. Furthermore, it has been shown that cumulants are also useful for identifying voiced and unvoiced segments in noisy speech signals.Master Thesis Rc8660 Ses Sentezleyici ile Türkçe Metinden Konuşma Sentezleme(2015) Karamehmet, Timur; Tora, Hakan; Uslu, İbrahim BaranBu çalışma, metinden konuşma sentezleme problemini ve RC8660 gömülü sisteminin Türkçe'ye uyarlanması için yapılan çalışmaları incelemektedir. Tezde, İngilizce fonemlerle yüklü gelen RC8660 kartının Türkçe konuşma sentezlemesi hedeflenmiştir. Bu amaçla, öncelikle İngilizce'de bulunan fonemlere karşılık gelen Türkçe fonemler tanımlanmıştır. Bunun için IPA: International Phonetic Alphabet'den yararlanılmıştır. Türkçe ve İngilizce'nin hece yapıları farklı olduğu için, kartın sahip olduğu metin ve fonem modlarından yararlanılarak yeni bir harici sözlük tanımlamaya ihtiyaç duyulmuştur. Doğru heceleme için gerekli kurallar, oluşturulan bu sözlüğe tek tek eklenmiştir. RC8660'ın bir konuşmacı doğallığında Türkçe konuşması için vurgu ve tonlama kuralları da tanımlanmıştır. Üretilen konuşmanın düzgün ve anlaşılabilir olması amacıyla karakterler ve sayılar için farklı fonemler kullanılmıştır. Kartın yazılımı olan RC Studio'da yer alan hız, ifade, perde, formant frekansı, ton, gecikme ve telaffuz ayarlarının konuşma üzerindeki etkileri de test edilmiştir. Üretilen konuşmanın kalitesi ortalama görüş skoru (MOS) testi ile ölçülmüştür.Master Thesis Avuç İçi Tanımlaması(2018) Jebrıel, Belal Alı Mesbah; Tora, HakanBu tez, standart bir veritabanı ve bir temizleyici aracılığıyla avuç izi tanımlanmasının uygunluğunu araştırmaktadır. Bu çalışma, sol el ve sağ el görüntüleri içeren veritabanları CASIA ve IIT için iki öznitelik kümesi kullanmaktadır. Yerel ikili örüntü (YİÖ) ve yönlü gradyan histogram (YGH) öznitelikleri, MATLAB tarafından görüntülerden elde edilmiştir. Eğitim ve test setleri bu özelliklerden oluşturuldu. Çok katmanlı katmanlı bir sinir ağı ve lineer ve kuadratik kernel kullanan destek vektör makineleri (DVM), seçilen veritabanlarında eğitilmiş ve test edilmiştir. Seçilen özellikler deneysel olarak birbirleriyle karşılaştırılmıştır. Her iki sınıflandırıcı için YGH'de daha iyi sonuçlar elde edilmiştir. Ayrıca, sınıflandırıcıların performansı da değerlendirilmiştir. Sinir ağın, her iki veri setinin YİÖ öznitelikleri için SVM'den daha iyi sonuçlar verdiği gözlenmiştir. Ancak, YGH özellikleri için birbirlerine göre çok fazla avantajları yoktur. Anahtar Kelimeler: Avuç izi tanımlama, yerel ikili örüntü (YİÖ), yönlü gradyan histogramı (YGH), sinir ağları, destek vektör makinesi (DVM).Conference Object Segmentation of Isolated Words Into Voiced-Unvoiced Sound Components by Kurtosis;(Institute of Electrical and Electronics Engineers Inc., 2015) Uslu,B.; Tora, Hakan; Tora,H.; Tora, Hakan; Airframe and Powerplant Maintenance; Airframe and Powerplant MaintenanceThis study presents a new approach to the segmentation of isolated words into their voiced/ unvoiced parts. It is well known that voiced/ unvoiced discrimination has an important role in speech synthesis and coding applications. The offered method makes this discrimination using the kurtosis values of the words. The performance of the proposed approach was tested on Turkish digit recordings from zero to nine. It has been observed that this approach segments the parts successfully in not only clean speech but also in noisy speech. © 2015 IEEE.Conference Object Segmentation of Isolated Words Into Voiced-Unvoiced Sound Components by Kurtosis(Ieee, 2015) Uslu, Baran; Tora, HakanThis study presents a new approach to the segmentation of isolated words into their voiced/unvoiced parts. It is well known that voiced/unvoiced discrimination has an important role in speech synthesis and coding applications. The offered method makes this discrimination using the kurtosis values of the words. The performance of the proposed approach was tested on Turkish digit recordings from zero to nine. It has been observed that this approach segments the parts successfully in not only clean speech but also in noisy speech.Article Citation - WoS: 2Citation - Scopus: 2Risk Assessment of Sea Level Rise for Karasu Coastal Area, Turkey(Mdpi, 2023) Eliawa, Ali; Genc, Asli Numanoglu; Tora, Hakan; Maras, Hadi HakanSea Level Rise (SLR) due to global warming is becoming a more pressing issue for coastal zones. This paper presents an overall analysis to assess the risk of a low-lying coastal area in Karasu, Turkey. For SLR scenarios of 1 m, 2 m, and 3 m by 2100, inundation levels were visualized using Digital Elevation Model (DEM). The eight-side rule is applied as an algorithm through Geographic Information System (GIS) using ArcMap software with high-resolution DEM data generated by eleven 1:5000 scale topographic maps. The outcomes of GIS-based inundation maps indicated 1.40%, 6.02%, and 29.27% of the total land area by 1 m, 2 m, and 3 m SLR scenarios, respectively. Risk maps have shown that water bodies, low-lying urban areas, arable land, and beach areas have a higher risk at 1 m. In a 2 m scenario, along with the risk of the 1 m scenario, forests become at risk as well. For the 3 m scenario, almost all the territorial features of the Karasu coast are found to be inundated. The effect of SLR scenarios based on population and Gross Domestic Product (GDP) is also analyzed. It is found that the 2 and 3 m scenarios lead to a much higher risk compared to the 1 m scenario. The combined hazard-vulnerability data shows that estuarine areas on the west and east of the Karasu region have a medium vulnerability. These results provide primary assessment data for the Karasu region for the decision-makers to enhance land use policies and coastal management plans.Conference Object Citation - WoS: 1Recognition of Hand-Sketched Digital Logic Gates(Ieee, 2015) Gul, Nuray; Tora, HakanHand-Sketched circuit recognition is a very useful tool in engineering area. Because most of the engineers prefer to design their circuits on the paper firstly. So, this can cause time wasting and some mistakes. In this study, which is based on the solving these kinds of problems, classification and recognition of the handwritten digital logic gates according to their complex and scalar FDs (Fourier Descriptors) is presented. Test results are obtained as 84.3 % accuracy rate for complex FDs, 98.6 % for scalar FDs. Then these results are compared and decided the optimum FDs type for this study.Article Citation - WoS: 13Citation - Scopus: 16A Novel Data Encryption Method Using an Interlaced Chaotic Transform(Pergamon-elsevier Science Ltd, 2024) Gokcay, Erhan; Tora, HakanWe present a novel data encryption approach that utilizes a cascaded chaotic map application. The chaotic map used in both permutation and diffusion is Arnold's Cat Map (ACM), where the transformation is periodic and the encrypted data can be recovered. The original format of ACM is a two-dimensional mapping, and therefore it is suitable to randomize the pixel locations in an image. Since the values of pixels stay intact during the transformation, the process cannot encrypt an image, and known-text attacks can be used to get back the transformation matrix. The proposed approach uses ACM to shuffle the positions and values of two-dimensional data in an interlaced and nested process. This combination extends the period of the transformation, which is significantly longer than the period of the initial transformation. Furthermore, the nested process's possible combinations vastly expand the key space. At the same time, the interlaced pixel and value transformation makes the encryption highly resistant to any known-text attacks. The encrypted data passes all random-data tests proposed by the National Institute of Standards and Technology. Any type of data, including ASCII text, can be encrypted so long as it can be rearranged into a two-dimensional format.
