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Full-Text Articles in Physical Sciences and Mathematics
Bandwidth Extension Of Narrowband Speech In Log Spectra Domain Using Neural Network, Sara Pourmohammadi, Mansour Vali, Mohsen Ghadyani
Bandwidth Extension Of Narrowband Speech In Log Spectra Domain Using Neural Network, Sara Pourmohammadi, Mansour Vali, Mohsen Ghadyani
Turkish Journal of Electrical Engineering and Computer Sciences
In recent years, there have been significant advances in communication technology, but speech signals still suffer from low perceived quality caused by bandwidth limitations of telephone networks. The bandwidth extension (BWE) approach adds high-frequency components of the speech signal to band-limited telephone speech and increases speech perception significantly. In this work, we develop a new method for representation of vocal tract filter coefficients using log of filter bank energy (LFBE) parameters as an alternative for mel-frequency cepstral coefficients (MFCCs). This approach is based on a strong correlation between the spectral components of low- and high-band spectrums. Furthermore, the performances of …
An Intelligence-Based Islanding Detection Method Using Dwt And Ann, Mehrdad Heidari, Ghodratollah Seifossadat, Morteza Razaz
An Intelligence-Based Islanding Detection Method Using Dwt And Ann, Mehrdad Heidari, Ghodratollah Seifossadat, Morteza Razaz
Turkish Journal of Electrical Engineering and Computer Sciences
In this paper, a new method based on artificial neural network (ANN) and discrete wavelet transform (DWT) is proposed for electrical islanding detection. Transient signals produced during an event are used in the proposed method. ANN is trained to classify the transient events as islanding and nonislanding. The required features for classifying are extracted through DWT of voltage and current transient signals. The proposed method is then simulated on a medium voltage distribution system of CIGRE with 2 kinds of DGs. Results show that this method can detect electrical islands more rapidly and accurately.
Rfid Card Security For Public Transportation Applications Based On A Novel Neural Network Analysis Of Cardholder Behavior Characteristics, Gürsel Düzenli̇
Rfid Card Security For Public Transportation Applications Based On A Novel Neural Network Analysis Of Cardholder Behavior Characteristics, Gürsel Düzenli̇
Turkish Journal of Electrical Engineering and Computer Sciences
This paper proposes a novel approach that applies neural network forecasting to security for closed-loop prepaid cards based on low-cost technologies such as RFID and 1-Wire. The security vulnerability of low-cost RFID closed-loop prepaid card systems originates mostly from the card itself. Criminal organizations counterfeit or clone card data. Although high-security prepaid cards exist, they are often too expensive for transport ticketing, and even their security is not guaranteed for a well-defined period of time. Therefore, data encryption systems are used widely against counterfeiting with success. However, it has not been possible to develop countermeasures with comparable success against cloning. …
Improving The Drain-Current Expression Of Bsim4 For Hot-Carrier Degradation Modeling That Is Suitable For Analog Applications, Gürsel Düzenli̇
Improving The Drain-Current Expression Of Bsim4 For Hot-Carrier Degradation Modeling That Is Suitable For Analog Applications, Gürsel Düzenli̇
Turkish Journal of Electrical Engineering and Computer Sciences
The reliability evaluation of MOS transistors is one of the most important subjects in device engineering and VLSI design. The down-scaling of device dimensions adversely affects device reliability and lifetime. Although different factors contribute to device reliability and lifetime, the most influential factor is hot-carrier degradation. Furthermore, hot-carrier degradation affects each application uniquely. In analog applications, hot-carrier degradation is more complex and diverse relative to digital applications. In this study, we improve the BSIM4 drain-current model to develop a hot-carrier degradation model that is suitable for both analog and digital applications. Our approach is readily applicable to all process technologies …