The Impact Of Transmission Power Levels Set Size On Lifetime Of Wireless Sensor Networks In Smart Grids,
2018
TÜBİTAK
The Impact Of Transmission Power Levels Set Size On Lifetime Of Wireless Sensor Networks In Smart Grids, Hüseyi̇n Uğur Yildiz
Turkish Journal of Electrical Engineering and Computer Sciences
Wireless sensor networks (WSNs) have been confirmed as one of the most promising technologies for many smart grid (SG) applications due to their low complexity and inexpensive costs. A typical WSN is formed with numerous battery limited sensor nodes mounted on critical components of a SG system for monitoring applications. Acquired monitoring data by sensor nodes are conveyed to the base station generally by using multihop communication techniques. WSN-based SG applications encounter severe propagation losses due to extreme channel conditions of the SG environment. In order to reduce possible packet errors caused by channel variations, transmission power control approaches can …
Improved Design Of Axial Flux Permanent Magnet Generator For Small-Scale Wind Turbine,
2018
TÜBİTAK
Improved Design Of Axial Flux Permanent Magnet Generator For Small-Scale Wind Turbine, Mojtaba Eldoromi, Sajjad Tohidi, Mohammad Reza Feyzi, Naghi Rostami, Reza Emadifar
Turkish Journal of Electrical Engineering and Computer Sciences
Recently, much attention has been given to axial flux permanent magnet generators due to some advantages such as high efficiency, high power density, and higher torque compared to radial flux generators. In addition, increased number of poles makes them appropriate for low-speed applications such as wind power generators. In this study, an axial flux permanent magnet synchronous generator with unique features such as high power density is designed for small-scale wind turbines. The structure of generator includes a rotor and a stator. The generator is designed and then analyzed by Flux 11.2 software. The analysis includes the effects of air …
Average Modeling And Evaluation Of 18-Pulse Autotransformer Rectifier Unit Without Interphase Transformers,
2018
TÜBİTAK
Average Modeling And Evaluation Of 18-Pulse Autotransformer Rectifier Unit Without Interphase Transformers, Shahbaz Khan, Xiaobin Zhang, Husan Ali, Haider Zaman, Muhammad Saad, Bakht Muhammad Khan
Turkish Journal of Electrical Engineering and Computer Sciences
This paper presents an improved average model and evaluation of an 18-pulse autotransformer rectifier unit (ATRU) in differential delta configuration. Average models remove the switching behavior of diode rectifiers and high bandwidth transients, which not only facilitates simulation of power systems by reducing computational cost but also enables impedance-based stability analysis for large complex power systems. To experimentally validate the proposed average model, a 2-kW, 18-pulse ATRU has been tested and the results of the derived model are compared with those of the switching model and experimental prototype. Computed transfer function of load impedance from the proposed average model closely …
L-Index Based Contingency Filtering For Voltage Stability Constrained Reactive Power Planning,
2018
TÜBİTAK
L-Index Based Contingency Filtering For Voltage Stability Constrained Reactive Power Planning, Farid Karbalaei, Shahriar Abbasi
Turkish Journal of Electrical Engineering and Computer Sciences
One of the most important objectives in reactive power planning (RPP) is maintaining required voltage stability margin under normal and single-contingency situations. For this, an optimization problem must be formulated considering N-1 contingencies constrained for a set of predetermined contingencies. Traditionally, all these contingencies must simultaneously be addressed in the optimization problem. This can dramatically increase the problem dimension and decrease the convergence ability of its solution for large scale applications. This paper uses an L-index based contingency filtering strategy to select a small number of contingencies to be addressed in RPP problem. For this, the predetermined set of all …
Application Of Acf-Wavelet Feature Extraction For Classification Of Some Artificial Pd Models Of Power Transformer,
2018
TÜBİTAK
Application Of Acf-Wavelet Feature Extraction For Classification Of Some Artificial Pd Models Of Power Transformer, Vahid Parvin Darabad
Turkish Journal of Electrical Engineering and Computer Sciences
In this paper, 7 different artificial partial discharge (PD) models of power transformer defect types are built in a high voltage laboratory, and then PD signals are recorded in the whole power frequency cycle to develop a preliminary PD knowledge base. A specific technique is used to extract single PD events from the recorded knowledge base. By application of wavelet transform, different decomposition levels of extracted PD signals are investigated. Feature extraction is performed by application of statistic moments on the autocorrelation function of PD signal decompositions. "Best" features are selected based on the F-test. To evaluate the performance of …
Controlling The Speed And Flux Of A Dual Stator Winding Induction Motor Using An Emotional Intelligent Controller And Integration Algorithm, Hojat Moayedirad, Mohammad Ali Shamsi Nejad
Turkish Journal of Electrical Engineering and Computer Sciences
The appropriate efficiency of a dual stator winding squirrel-cage induction motor (DSWIM) is obtained when the ratio of two frequencies feeding the machine is equal to the ratio of the number of poles. In the vector control method, the estimation of flux at low speed is difficult. To solve this problem, researchers have benefited from the free capacity of the two windings of the stator. This makes the motor deviate from its standard operating mode at low speed. The main purpose of the present study is to reduce the power losses of the inverter units in the sensorless DSWIM drive …
Constrained Multiobjective Pso And T-S Fuzzy Models For Predictive Control,
2018
TÜBİTAK
Constrained Multiobjective Pso And T-S Fuzzy Models For Predictive Control, Ali Thamallah, Anis Sakly, Faouzi M'Sahli
Turkish Journal of Electrical Engineering and Computer Sciences
Multiobjective optimization problems are still a challenging area in the field of control system engineering. In this context, the current study describes a new multivariable predictive control scheme formulated by using the T-S fuzzy modeling method and a new constrained multiobjective PSO algorithm. The T-S fuzzy modeling technique is applied to forecast the behaviors of the nonlinear system. It also aims at establishing some conditions so that the proposed control loop is asymptotically stable. The obtained experimental results show that the combination of the philosophy of the T-S fuzzy model and multiobjective PSO is very good in the controlling of …
A Model-Based Transformation Framework For Designing And Analyzing Wireless Sensor Networks,
2018
TÜBİTAK
A Model-Based Transformation Framework For Designing And Analyzing Wireless Sensor Networks, Raoudha Saida, Yessine Hadj Kacem, Mohammed Sulaiman Bensaleh, Mohamed Abid
Turkish Journal of Electrical Engineering and Computer Sciences
Wireless sensor networks (WSNs) comprise resource-constrained (e.g., memory, processing, and energy) sensor nodes that are deployed in different areas and are able to monitor environmental conditions. Simulation has been widely used in order to evaluate the network performance. In this context, software designers need to evaluate, refine, and validate high-level models for WSN applications at early stages of development via simulation tools, in particular for WSN applications supporting energy-harvesting devices. In the present paper, we propose a model-based transformation framework that allows the modeling and simulation of a WSN system supporting energy-harvesting capabilities. In this proposal, we start from a …
New Optimization Algorithm Inspired By Fluid Mechanics For Combined Economic And Emission Dispatch Problem,
2018
TÜBİTAK
New Optimization Algorithm Inspired By Fluid Mechanics For Combined Economic And Emission Dispatch Problem, Ruyi Dong, Shengsheng Wang
Turkish Journal of Electrical Engineering and Computer Sciences
With the increasing concern over environmental protection, the combined economic emission dispatch (CEED) problem has received much attention. It needs to minimize both fuel cost and emission pollution. This study aims to propose a new metaheuristic algorithm inspired by fluid mechanics to solve the CEED problem with the weighted sum method. The new algorithm simulates the inverse process of fluid flowing spontaneously from high pressure to low pressure, similar to the optimization process of the CEED problem. When applied in two real-world cases, the new algorithm achieves better performance compared with other algorithms in the literature.
A Distributed Admm Approach For Energy-Efficient Resource Allocation In Mobile Edge Computing,
2018
TÜBİTAK
A Distributed Admm Approach For Energy-Efficient Resource Allocation In Mobile Edge Computing, Weiwei Fang, Wenchen Zhou, Yangyang Li, Xuening Yao, Feng Xue, Naixue Xiong
Turkish Journal of Electrical Engineering and Computer Sciences
Mobile edge computing (MEC) is a new promising technique to provide cloud-computing capabilities at the edge of cellular networks in close proximity to mobile users. In this paper, we consider joint optimization of the communication and computation resources in a multiuser, multiserver MEC system. The objective of this optimization problem is to minimize the total energy consumption of mobile devices under the time-sharing constraint. Given the fact that no coordination is involved between mobile devices, we propose a light-weight and decentralized algorithm based on the alternating direction method of multipliers (ADMM) framework. Experimental results demonstrate that the proposed algorithm performs …
Extending Co-Citation Using Sections Of Research Articles,
2018
TÜBİTAK
Extending Co-Citation Using Sections Of Research Articles, Arjumand Yar Khan, Abdul Shahid Khattak, Muhammad Tanvir Afzal
Turkish Journal of Electrical Engineering and Computer Sciences
The excessive amount of digital information has made it crucial to extract the relevant information. This hinders researchers in finding documents pertaining to their research. There exist various state-of-the-art techniques, such as co-citation, bibliographic coupling, and their recent extensions like citation proximity analysis and citation order analysis, that recommend the relevant documents against the posed query. Most of these approaches are statistical in nature and thus can further be extended by incorporating some semantics to enhance the results. In this paper, we present an extension of a co-citation-based technique to identify the most relevant documents to co-cited document(s). The proposed …
Influence Maximization In Social Networks: An Integer Programming Approach,
2018
TÜBİTAK
Influence Maximization In Social Networks: An Integer Programming Approach, Muhammed Emre Keski̇n, Mehmet Güray Güler
Turkish Journal of Electrical Engineering and Computer Sciences
The use of social networks has been spreading rapidly in recent years. There is a growing interest in influence maximization in social networks, especially after observing that the effects of social events of the Arab Spring, Gezi events of Turkey, uprising in Ukraine, etc. have been built by the help of social networks. Consequently, many institutions like political parties or commercial firms are willing to spread their messages throughout social networks. There are many studies that concentrate on finding the most influential initial nodes, called seeds, which maximize the spread of an intended message over the social network. However, most …
Improvement Of Heart Attack Prediction By The Feature Selection Methods,
2018
TÜBİTAK
Improvement Of Heart Attack Prediction By The Feature Selection Methods, Hi̇dayet Takci
Turkish Journal of Electrical Engineering and Computer Sciences
Prediction of a heart attack is very important since it is one of the leading causes of sudden death, especially in low-income countries. Although cardiologists use traditional clinical methods such as electrocardiography and blood tests for heart attack prediction, computer aided diagnosis systems that use machine learning methods are also in use for this task. In this study, we used machine learning and feature selection algorithms together. Our aim is to determine the best machine learning method and the best feature selection algorithm to predict heart attacks. For this purpose, many machine learning methods with optimum parameters and several feature …
Estimating Left Ventricular Volume With Roi-Based Convolutional Neural Network,
2018
TÜBİTAK
Estimating Left Ventricular Volume With Roi-Based Convolutional Neural Network, Feng Zhu
Turkish Journal of Electrical Engineering and Computer Sciences
The volume of the human left ventricular (LV) chamber is an important indicator for diagnosing heart disease. Although LV volume can be measured manually with cardiac magnetic resonance imaging (MRI), the process is difficult and time-consuming for experienced cardiologists. This paper presents an end-to-end segmentation-free method that estimates LV volume from MRI images directly. The method initially uses Fourier transform and a regression filter to calculate the region of interest that contains the LV chambers. Then convolutional neural networks are trained to estimate the end-diastolic volume (EDV) and end-systolic volume (ESV). The resulting models accurately estimate the EDV and ESV …
Gnss Augmentation Through Ku-Band Communication Satellites With Rtkrealization,
2018
TÜBİTAK
Gnss Augmentation Through Ku-Band Communication Satellites With Rtkrealization, Şenol Gülgönül
Turkish Journal of Electrical Engineering and Computer Sciences
In this study, a method to broadcast real-time kinematics (RTK) corrections over a communication satellite is proposed. RTK corrections generated by the reference station are uplinked to the communication satellite within a multiplexed DVB-S carrier. Corrections are received by a satellite dish and the DVB-S satellite receiver. Better than 18 cm of accuracy is achieved for rover distances of up to 500 km in Turkey. The proposed method can be used as an alternative satellite-based augmentation system for Turkey and other countries.
Real-Time Chaff Generation For A Biometric Fuzzy Vault,
2018
TÜBİTAK
Real-Time Chaff Generation For A Biometric Fuzzy Vault, Manvjeet Kaur, Sanjeev Sofat
Turkish Journal of Electrical Engineering and Computer Sciences
Biometric technology is rapidly being adopted in wide variety of security applications. However, the system itself is not completely foolproof and is vulnerable to many attacks. Some of the attacks on the biometric system are very severe, one of which is the attack on template security. In spite of the various template security techniques presented in the literature, none of them is able to provide security, diversity, revocability, and good performance simultaneously to the biometric system. Fuzzy vault is one of the most promising bio-cryptographic techniques to prevent the template data from being misused. To make the fuzzy vault practically …
A Strategy For Improving Netclust Server Placement For Multicloud Environments,
2018
TÜBİTAK
A Strategy For Improving Netclust Server Placement For Multicloud Environments, Yuting Zhao, Jinhong Liu, Qing Fang, Lifang Xu, Changlai Du, Yuan Xiaoqun
Turkish Journal of Electrical Engineering and Computer Sciences
In this paper, we propose a fast server placement algorithm to improve the NetClust framework and make it more efficient and exible. To this end, we introduce hierarchical clustering technologies to the NetClust framework and propose a exible server placement algorithm, which integrates the agglomerative and divisive clustering technologies to reduce the time complexity and avoid the performance uctuation affected by the initial node selection. The experiment results show that our server placement algorithm may reduce the time complexity of server selection of NetClust significantly and improve the exibility and applicability of the NetClust.
An Efficient Algorithm To Decompose A Compound Rectilinear Shape Into Simplerectilinear Shapes,
2018
TÜBİTAK
An Efficient Algorithm To Decompose A Compound Rectilinear Shape Into Simplerectilinear Shapes, Imran Sharif, Debasis Chaudhuri, Naveen Kushwaha, Ashok Samal, Brij Mohan Singh
Turkish Journal of Electrical Engineering and Computer Sciences
Detection of a compound object is a critical problem in target recognition. For example, buildings form an important class of shapes whose recognition is important in many remote sensing based applications. Due to the coarse resolution of imaging sensors, adjacent buildings in the scenes appear as a single compound shape object. These compound objects can be represented as the union of a set of disjoint rectilinear shaped objects. Separating the individual buildings from the resulting compound objects in a segmented image is often difficult but important nevertheless. In this paper we propose a new and efficient technique to decompose a …
A New Method Based On Pixel Density In Salt And Pepper Noise Removal,
2018
TÜBİTAK
A New Method Based On Pixel Density In Salt And Pepper Noise Removal, Uğur Erkan, Levent Gökrem
Turkish Journal of Electrical Engineering and Computer Sciences
In this paper, we deliver a new method to remove salt and pepper noise, which we refer to as based on pixel density filter (BPDF). The first step of the method is to determine whether or not a pixel is noisy, and then we decide on an adaptive window size that accepts the noisy pixel as the center. The most repetitive noiseless pixel value within the window is set as the new pixel value. By using 18 test images, we give the results of peak signal-to-noise ratio (PSNR), structural similarity (SSIM), image enhancement factor (IEF), standard median filter (SMF), adaptive …
Blood Glucose Control Using An Abc Algorithm-Based Fuzzy-Pid Controller,
2018
TÜBİTAK
Blood Glucose Control Using An Abc Algorithm-Based Fuzzy-Pid Controller, Seli̇m Soylu, Kenan Danişman
Turkish Journal of Electrical Engineering and Computer Sciences
In this paper, a Mamdani-type fuzzy controller is proposed as the controller part of an artificial pancreas. The controller is optimized with the artificial bee colony optimization algorithm. The glucose{insulin regulatory system, based on a nonlinear differential model in the presence of delay, is used both for virtual patient and healthy person data. The main target of the controller is to mimic a blood glucose concentration profile of the healthy person with exogenous insulin infusion. Simulations are performed to assess the control function in terms of tracking the blood glucose concentration profile of the healthy person and minimizing errors. To …
