The Detailed Analysis Of Rate Equation Roots Of Bh-Laser Diode Using Volterra Series,
2015
TÜBİTAK
The Detailed Analysis Of Rate Equation Roots Of Bh-Laser Diode Using Volterra Series, Remzi̇ Yildirim, Ahmet Karaarslan
Turkish Journal of Electrical Engineering and Computer Sciences
In this study, the rate equation analysis of a BH-laser diode was performed for output carrier density (N_o) using the zero-degree solution of the Volterra series. The carrier rate equation of the laser diode was analyzed in terms of input carrier density (N_i) and output carrier density modeling (N_i-N_o), with respect to the DC current (I_o). The polynomial root, which is obtained from the zero-degree solution (N_o) and limit values of I_o, was found. For the linear operation of the laser diode, the range of I_o current was also determined using a linearization approach and the maximum value of N_o.
Efficient Id-Based Authentication And Key Agreement Protocols For The Session Initiation Protocol,
2015
TÜBİTAK
Efficient Id-Based Authentication And Key Agreement Protocols For The Session Initiation Protocol, Haci Hakan Kilinç, Yolguly Allaberdiyev, Tuğrul Yanik, Serdar Süer Erdem
Turkish Journal of Electrical Engineering and Computer Sciences
In a widely deployed VoIP system tens of thousands of clients compete for the SIP proxy server's authentication service. SIP protocol implementations have to meet certain QoS and security requirements. In this study new ID-based protocols are proposed for the SIP authentication and key agreement protocols. These protocols minimize the use of expensive pairing functions but still resist notable attacks. The security of the proposed protocols are analyzed and demonstrated with security proofs based on the BJM security model. Finally, the performance overhead of the proposed protocols are compared to ID-based SIP authentication and key agreement protocols given in the …
A Fault Detection, Diagnosis, And Reconfiguration Method Via Support Vector Machines},
2015
TÜBİTAK
A Fault Detection, Diagnosis, And Reconfiguration Method Via Support Vector Machines}, Rana Ortaç Kabaoğlu
Turkish Journal of Electrical Engineering and Computer Sciences
This paper presents a fault detection, diagnosis, and reconfiguration method based on support vector machines. This method is appropriate for certain or predetermined faults and involves a fault detection and diagnosis unit and an online controller selection type reconfiguration mechanism. In this method, when a fault is detected and diagnosed by the fault detection and diagnosis unit, a suitable controller, which has been determined via an optimization algorithm in an off-line fashion, is activated to maintain proper closed-loop performance of the system in an on-line manner. In the detection, diagnosis, and reconfiguration stages of the method, support vector classification and …
Design And Control Of A Visual Servomechanism For Automating Corneal Cross-Linking Treatment In Keratoconus Patients,
2015
TÜBİTAK
Design And Control Of A Visual Servomechanism For Automating Corneal Cross-Linking Treatment In Keratoconus Patients, Onurcan Şahi̇n, Erdi̇nç Altuğ
Turkish Journal of Electrical Engineering and Computer Sciences
A novel mechatronic system designed for automated corneal cross-linking (CCL) treatment in keratoconus patients is introduced. Keratoconus is a serious illness that if not treated may cause serious distortion of vision. Currently, the CCL operation, which is the most promising treatment of this disease, is performed manually. The automated system developed is the first of its kind to automate the treatment with visual feedback, and it aims to increase the efficiency in treatment and to eliminate any potential side effects and risks of the treatment. To track the eye of the patient, the system consists of a camera, an image …
A New Feature Selection Model Based On Id3 And Bees Algorithm For Intrusion Detection System,
2015
TÜBİTAK
A New Feature Selection Model Based On Id3 And Bees Algorithm For Intrusion Detection System, Adel Sabry Eesa, Zeynep Orman, Adnan Mohsin Abdulazeez Brifcani
Turkish Journal of Electrical Engineering and Computer Sciences
Intrusion detection systems (IDSs) have become a necessary component of computers and information security framework. IDSs commonly deal with a large amount of data traffic and these data may contain redundant and unimportant features. Choosing the best quality of features that represent all of the data and exclude the redundant features is a crucial topic in IDSs. In this paper, a new combination approach based on the ID3 algorithm and the bees algorithm (BA) is proposed to select the optimal subset of features for an IDS. The BA is used to generate a subset of features, and the ID3 algorithm …
Dwmt Transceiver Equalization Using Overlap Fde For Downlink Adsl,
2015
TÜBİTAK
Dwmt Transceiver Equalization Using Overlap Fde For Downlink Adsl, Arsla Khan, Sobia Baig, Tabassum Nawaz
Turkish Journal of Electrical Engineering and Computer Sciences
Discrete wavelet multitone (DWMT) modulation is a wavelet transform based technique implemented using perfect reconstruction filter banks. It has been recently proposed for various wireline channels such as digital subscriber loops (DSLs) as a solution to the problems posed by a discrete multitone (DMT) transceiver including interblock interference (IBI) and lower spectral efficiency due to the employment of a cyclic prefix (CP) in the guard interval (GI) for DMT symbols. The greater side lobe attenuation offered by wavelet filter banks results in improved spectral containment and lower IBI in DWMT transceivers. However, no standard equalization technique exists for a DWMT …
Performance Of Support Vector Regression Machines On Determining The Magnetic Characteristics Of The E-Core Transverse Flux Machine, Çi̇ğdem Gündoğan Türker, Feri̇ha Erfan Kuyumcu, Nurhan Türker Tokan
Turkish Journal of Electrical Engineering and Computer Sciences
The E-core transverse flux machine (ETFM) has major advantages with its different and unique structure in conventional electrical machines. It is a combination of transverse flux and reluctance principle. In this work, support vector regression machines (SVRMs) are used to obtain the magnetic characteristic parameters of the ETFM for the first time and it is compared with its artificial neural network model. The data for the training and testing of the SVRMs are obtained from experimental measurements. It is proven that SVRMs can conveniently be used in the modeling of the magnetic behaviors of highly nonlinear ETFM with better accuracy …
A Novel Adaptive Filter Design Using Lyapunov Stability Theory,
2015
TÜBİTAK
A Novel Adaptive Filter Design Using Lyapunov Stability Theory, Engi̇n Cemal Mengüç, Nuretti̇n Acir
Turkish Journal of Electrical Engineering and Computer Sciences
This paper presents a new approach to design an adaptive filter using Lyapunov stability theory. The design procedure is formulated as an inequality constrained optimization problem. Lagrange multiplier theory is used as an optimization tool. Lyapunov stability theory is integrated into the constraint function to satisfy the asymptotic stability of the proposed filtering system. The tracking capability is improved by using a new analytical adaptation gain rate, which has the ability to adaptively adjust itself depending on a sequential tracking square error rate. The fast and robust convergence ability of the proposed algorithm is comparatively examined by simulation examples.
An E-Nose-Based Indoor Air Quality Monitoring System: Prediction Of Combustible And Toxic Gas Concentrations,
2015
TÜBİTAK
An E-Nose-Based Indoor Air Quality Monitoring System: Prediction Of Combustible And Toxic Gas Concentrations, Beki̇r Mumyakmaz, Keri̇m Karabacak
Turkish Journal of Electrical Engineering and Computer Sciences
A system for monitoring and predicting indoor air quality level is proposed in this paper. The system comprises a computer with a monitoring program and a sensor cell, which has an array of metal oxide gas sensors along with a temperature and humidity sensor. The gas sensors in the cell have been chosen to detect only hydrogen, methane, and carbon monoxide gases. Methane was selected as a representative for indoor combustible gases, and carbon monoxide was used to represent indoor toxic gases. Hydrogen was used as an interfering (and also combustible) gas in the study. A number of experiments were …
Novel Congestion Control Algorithms For A Class Of Delayed Networks,
2015
TÜBİTAK
Novel Congestion Control Algorithms For A Class Of Delayed Networks, Shoorangiz Shams Shamsabad Farahani, Mohammad Reza Jahed Motlagh, Mohammad Ali Nekoui
Turkish Journal of Electrical Engineering and Computer Sciences
Time delays are often instability sources and give rise to undesired oscillation and performance degradation, so it is necessary to consider delay in general congestion control schemes. In this paper, a new system model for wireless sensor networks (WSNs) is established in discrete time, subsystems including delay are presented, and the overall model is achieved by blending these subsystems. For controller synthesis, common quadratic Lyapunov functions and a new approach based on nonquadratic Lyapunov functions are utilized, and a controller is designed to stabilize each subsystem. The controller synthesis results are expressed in terms of linear matrix inequalities. Moreover, the …
Forecasting The Day-Ahead Price In Electricity Balancing And Settlement Market Of Turkey By Using Artificial Neural Networks,
2015
TÜBİTAK
Forecasting The Day-Ahead Price In Electricity Balancing And Settlement Market Of Turkey By Using Artificial Neural Networks, Mehmet Ali̇ Kölmek, İsa Navruz
Turkish Journal of Electrical Engineering and Computer Sciences
In determination of electric energy price, most price information coming from bilateral contracts is effective, but the importance of the spot market (pool market) price cannot be ignored. Forecasting the spot market price is very crucial, especially for companies actively participating in the spot market and giving purchase and sale bids. An artificial neural network is a way frequently used for price forecasting research. In this study, simulation studies about price modeling via artificial neural networks and proper artificial neural network configurations are examined. After selection of different network topologies and parameters, attempts are made to observe network performance by …
Conceptual Design Of A Low-Cost Real-Time Hardware-In-The-Loop Simulator For Satellite Attitude Control System,
2015
TÜBİTAK
Conceptual Design Of A Low-Cost Real-Time Hardware-In-The-Loop Simulator For Satellite Attitude Control System, Farhad Bayat
Turkish Journal of Electrical Engineering and Computer Sciences
Integration of flight hardware with real-time simulation increases satellite attitude control system (ACS) reliability by providing greater test coverage through end-to-end testing in a realistic test environment. In this paper, a compound hardware and software simulator has been designed for evaluation and testing of the spacecraft ACS, placing emphasis on the real-time hardware-in-loop (RTHIL) architecture. The environment comprises both real-time control and data acquisition applications on a network of ACS hardware, the MATLAB Real-Time Workshop, and a PCI device to join the hardware and software units. Moreover, a graphical 3D simulator has been designed, enabling the designers and researchers to …
Detection Of Microcalcification In Digitized Mammograms With Multistable Cellular Neural Networks Using A New Image Enhancement Method: Automated Lesion Intensity Enhancer (Alie), Levent Ci̇vci̇k, Burak Yilmaz, Yüksel Özbay, Gani̇me Di̇lek Emli̇k
Turkish Journal of Electrical Engineering and Computer Sciences
Microcalcification detection is a very important issue in early diagnosis of breast cancer. Generally physicians use mammogram images for this task; however, sometimes analyzing these images become a hard task because of problems in images such as high brightness values, dense tissues, noise, and insufficient contrast level. In this paper, we present a novel technique for the task of microcalcification detection. This technique consists of three steps. The first step is focused on removing pectoral muscle and unnecessary parts from the mammogram images by using cellular neural networks (CNNs), which makes this a novel process. In the second step, we …
Emg Classification In Obstructive Sleep Apnea Syndrome And Periodic Limb Movement Syndrome Patients By Using Wavelet Packet Transform And Extreme Learning Machine, Necmetti̇n Sezgi̇n
Turkish Journal of Electrical Engineering and Computer Sciences
Electromyogram (EMG) signals, measured at the skin surface, provide crucial access to the muscle tones of a body. Some diseases, such as obstructive sleep apnea syndrome (OSAS) and periodic limb movement syndrome (PLMS), are closely associated with the electrical activity of muscle tones. In this paper, a hybrid model containing wavelet packet transform (WPT) plus an extreme learning machine (ELM) was proposed to classify EMG signals in OSAS and PLMS patients. At first, the WPT was used to extract the features of the EMG signal, and then these features were fed to the ELM classifier. The mean classification accuracy of …
An Ofdm Throughput Analysis For Cognitive Radio Application In Contiguous Or Noncontiguous Tv White Spaces,
2015
TÜBİTAK
An Ofdm Throughput Analysis For Cognitive Radio Application In Contiguous Or Noncontiguous Tv White Spaces, Cebrai̇l Çi̇fli̇kli̇, Ahmet Turgut Tuncer, Yusuf Öztürk
Turkish Journal of Electrical Engineering and Computer Sciences
Radio frequency spectrum is a finite and scarce resource. Efficient use of the radio frequency spectrum is a fundamental research issue. Since a large portion of the assigned radio frequency spectrum is used only sporadically, the bands currently allocated to TV services can be opportunistically reassigned to support broadband networking services while continuing to provide broadcast TV. The fragmented and unused TV channels named white spaces have a considerable amount of bandwidth potential and long transmission ranges. Bandwidth scalability can be supported by bonding multiple contiguous or noncontiguous consecutive channels using orthogonal frequency division multiplexing (OFDM)-based cognitive radio. In this …
Synthesis Of Real-Time Cloud Applications For Internet Of Things,
2015
TÜBİTAK
Synthesis Of Real-Time Cloud Applications For Internet Of Things, Slawomir Bak, Radoslaw Czarnecki, Stanislaw Deniziak
Turkish Journal of Electrical Engineering and Computer Sciences
This paper presents the methodology for the synthesis of real-time applications working in the ``Internet of Things'' environment. We propose the client-server architecture, where embedded systems act as smart clients and the Internet application is a server of the system. The architecture of the application conforms to the cloud computing model. Since centralized systems are prone to bottlenecks caused by accumulation of transmissions or computations, we propose the distributed architecture of the server and the methodology that constructs this architecture using Internet resources supported by a cloud provider. We assume that the function of the server is specified as a …
A Comparative Study Of Denoising Semg Signals,
2015
TÜBİTAK
A Comparative Study Of Denoising Semg Signals, Ulvi̇ Başpinar, Volkan Yusuf Şenyürek, Bariş Doğan, Hüseyi̇n Selçuk Varol
Turkish Journal of Electrical Engineering and Computer Sciences
Denoising of surface electromyography (sEMG) signals plays a vital role in sEMG-based mechatronics applications and diagnosis of muscular diseases. In this study, 3 different denoising methods of sEMG signals, empirical mode decomposition, discrete wavelet transform (DWT), and median filter, are examined. These methods are applied to 5 different levels of noise-added synthetic sEMG signals. For the DWT-based denoising technique, 40 different wavelet functions, 4 different threshold-selection-rules, and 2 threshold-methods are tested iteratively. Three different window-sized median filters are applied as well. The SNR values of denoised synthetic signals are calculated, and the results are used to select DWT and median …
Design And Analysis Of Ei Core Structured Transverse Flux Linear Reluctance Actuator,
2015
TÜBİTAK
Design And Analysis Of Ei Core Structured Transverse Flux Linear Reluctance Actuator, Ahmet Fenerci̇oğlu, Yusuf Avşar
Turkish Journal of Electrical Engineering and Computer Sciences
In this study, an EI core linear actuator is proposed for horizontal movement systems. It is a transverse flux linear switched reluctance motor designed with an EI core structure geometrically. The actuator is configured into three phases and at a 6/4 pole ratio, and it has a stationary active stator along with a sliding passive translator. The stator consists of E cores and the translator consists of I cores. The actuator has a yokeless design because the stator and translator have no back iron. The E and I cores are separated from each other to provide a fault-tolerant design and …
An Aggregate Indicator For Mobile Application Quality Assessment,
2015
TÜBİTAK
An Aggregate Indicator For Mobile Application Quality Assessment, Paul Pocatilu, Ion Ivan, Alin Zamfiroiu, Catalin Boja
Turkish Journal of Electrical Engineering and Computer Sciences
The mobile applications environment has a multitude of particularities generated by the complex system of devices, hardware, and software profiles and categories of users. The mobile industry has also evolved rapidly in the last 5 years from single-core mobile platforms to multiple-core mobile application platforms, able to compete in terms of user services with notebooks. New types of devices, like tablets, or shifts in human-computer interface paradigms from button click to screen touch, have opened new perspectives both for users and software developers. This requires an adaptable approach for performance analysis in terms of total quality management for software projects. …
A Performance Comparison Of Conventional And Transverse Flux Linear Switched Reluctance Motors,
2015
TÜBİTAK
A Performance Comparison Of Conventional And Transverse Flux Linear Switched Reluctance Motors, Nuretti̇n Üstkoyuncu, Krishnan Ramu
Turkish Journal of Electrical Engineering and Computer Sciences
This paper presents a comprehensive comparison between conventional (longitudinal flux) linear switched reluctance machines (CLSRMs) and transverse flux linear switched reluctance machines (TLSRMs) so as to enable engineers to choose a structure suitable for their applications. A commonly-used single-sided CLSRM and 4 different TLSRM structures are considered for the comparison. For a fair comparison of the 2 types of LSRMs, equal dimensions, including equal length and magnetomotive force, are applied as much as possible. The analytical approach and 3-dimensional finite element analysis (FEA) are employed to obtain the performance of these machines. It is proven analytically that the CLSRM has …
