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Full-Text Articles in Computer Sciences

New Metrics For Clustering Of Identical Products Over Imperfect Data, Zeki̇ Yetgi̇n, Furkan Gözükara Jan 2015

New Metrics For Clustering Of Identical Products Over Imperfect Data, Zeki̇ Yetgi̇n, Furkan Gözükara

Turkish Journal of Electrical Engineering and Computer Sciences

This paper introduces the concept of product identity-clustering based on new similarity metrics and new performance metrics for web-crawled products. Product identity-clustering is defined here as the clustering of identical products, e.g., for price comparison purposes. Products blindly crawled over web sources, e.g., online marketplaces, have different description formats, where the features describing the same products differ in both number and representation formats. This problem causes imperfect feature vectors, where the vectors are considered to be not uniform in length and structure, with the features of various data types (numeric, categorical), and unknown vector structures. Furthermore, the product information usually …


Rfid Card Security For Public Transportation Applications Based On A Novel Neural Network Analysis Of Cardholder Behavior Characteristics, Gürsel Düzenli̇ Jan 2015

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. …


A Fourth-Order Accurate Compact 2-D Fdfd Method For Waveguide Problems, Lokman Kuzu Jan 2015

A Fourth-Order Accurate Compact 2-D Fdfd Method For Waveguide Problems, Lokman Kuzu

Turkish Journal of Electrical Engineering and Computer Sciences

In this work, a fourth-order accurate 2-D finite difference frequency domain method is proposed for the analysis of general waveguide structures. Finite difference techniques have been extensively used to solve electromagnetic problems over the decades. These methods discretize the computational domain using the Yee cell, but the standard Yee scheme used in these methods is only second-order accurate. In order to demonstrate the advantages of the proposed scheme compared to the multiresolution frequency domain method and the traditional 2-D finite difference frequency domain scheme, the dispersion characteristics of various waveguide structures are analyzed.


An Aggregate Indicator For Mobile Application Quality Assessment, Paul Pocatilu, Ion Ivan, Alin Zamfiroiu, Catalin Boja Jan 2015

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. …


Fast Bitwise Pattern-Matching Algorithm For Dna Sequences On Modern Hardware, Giyasetti̇n Özcan, Osman Sabri̇ Ünsal Jan 2015

Fast Bitwise Pattern-Matching Algorithm For Dna Sequences On Modern Hardware, Giyasetti̇n Özcan, Osman Sabri̇ Ünsal

Turkish Journal of Electrical Engineering and Computer Sciences

We introduce a fast bitwise exact pattern-matching algorithm, which speeds up short-length pattern searches on large-sized DNA databases. Our contributions are two-fold. First, we introduce a novel exact matching algorithm designed specifically for modern processor architectures. Second, we conduct a detailed comparative performance analysis of bitwise exact matching algorithms by utilizing hardware counters. Our algorithmic technique is based on condensed bitwise operators and multifunction variables, which minimize register spills and instruction counts during searches. In addition, the technique aims to efficiently utilize CPU branch predictors and to ensure smooth instruction flow through the processor pipeline. Analyzing letter occurrence probability estimations …


Effective Cooperative Dtv Detection Using The Goertzel Algorithm, Selman Kulaç, Murat Hüsnü Sazli Jan 2015

Effective Cooperative Dtv Detection Using The Goertzel Algorithm, Selman Kulaç, Murat Hüsnü Sazli

Turkish Journal of Electrical Engineering and Computer Sciences

In digital TV (DTV) detection, to monitor the DTV spectrum, only pilot tone frequency values can be observed in order to achieve calculation and energy savings. These savings can be achieved using the Goertzel algorithm. However, more than one receiver sensor is needed in order to increase the detection quality. In this technique, the Goertzel algorithm is used for energy-efficient pilot tone detection and a new effective cooperative structure is proposed. There is no extra fusion center and more than one DTV band can be monitored with this OR rule-based cooperative structure. With this new cooperative structure, reaching the desired …


Optimization Of Electrical Power Transmission Lines'' Routing Using Ahp, Fuzzy Ahp, And Gis, Hasan Eroğlu, Musa Aydin Jan 2015

Optimization Of Electrical Power Transmission Lines'' Routing Using Ahp, Fuzzy Ahp, And Gis, Hasan Eroğlu, Musa Aydin

Turkish Journal of Electrical Engineering and Computer Sciences

With the increase of people's need for energy, electrical energy transmission has become a very important issue as well as electrical power generation. One of the most important problems in energy transmission is finding the best route in a very complex study area. To date, many people from different disciplines have come together to find the best routes by manual methods like using paper maps and deciding which route is the least-cost path (LCP) to the destination point. Today it is known that, in engineering problems, and especially in path-finding or site-placing problems, the Geographic Information System (GIS) is the …


Optimal Ipfc Damping Controller Design Based On Simplex Method And Self-Tuned Fuzzy Damping Scheme In A Two-Area Multimachine Power System, Ahmet Mete Vural, Kami̇l Çağatay Bayindir Jan 2015

Optimal Ipfc Damping Controller Design Based On Simplex Method And Self-Tuned Fuzzy Damping Scheme In A Two-Area Multimachine Power System, Ahmet Mete Vural, Kami̇l Çağatay Bayindir

Turkish Journal of Electrical Engineering and Computer Sciences

This paper develops a novel self-tuned fuzzy damping control scheme for an interline power flow controller (IPFC) to suppress the interarea mode of oscillations in a multimachine power system. The nonlinear adaptive damping controller is based on coordinated operation of two fuzzy inference systems. The first one produces the required $q$-axis voltage reference of the quasi multipulse series converter in response to generator angle oscillations, while the second one is used to tune the output of the first one online for further reducing the error signal using a given set of fuzzy rules. The simplex method is employed to search …


A New Bitwise Voting Strategy For Safety-Critical Systems With Binary Decisions, Mustafa Seçki̇n Durmuş, Oytun Eri̇ş, Uğur Yildirim, Mehmet Turan Söylemez Jan 2015

A New Bitwise Voting Strategy For Safety-Critical Systems With Binary Decisions, Mustafa Seçki̇n Durmuş, Oytun Eri̇ş, Uğur Yildirim, Mehmet Turan Söylemez

Turkish Journal of Electrical Engineering and Computer Sciences

The main issue in controlling safety-critical systems such as nuclear power reactors or railway interlocking systems is to provide high safety and reliability where the risk ratio is at the highest level because small errors might result in hazardous accidents (e.g., death or injury of many people). The N-version programming technique, where N-different modules run in parallel, can be used to improve the reliability and safety of such systems at the desired safety level. Decisions of N-different modules are then evaluated by another component, usually known as the voter, using different voting strategies. In the current study a bitwise voting …


A Novel Control Method For A Vsc-Hvdc System In A Grid-Connected Wind Farm, Yingpei Liu, Ran Li Jan 2015

A Novel Control Method For A Vsc-Hvdc System In A Grid-Connected Wind Farm, Yingpei Liu, Ran Li

Turkish Journal of Electrical Engineering and Computer Sciences

The voltage source converter-high voltage direct current (VSC-HVDC) transmission is the ideal integration technology for grid-connected wind farms. A passivity-based control (PBC) method for VSC-HVDC when the wind farm voltage is unbalanced is proposed in this paper. The mathematical model of a VSC with unbalanced voltage is established. The PBC theory including dissipation inequality and system strict passivity is introduced, and then the stability of PBC is proven in light of the Lyapunov stability theory. According to PBC theory, a Euler--Lagrange mathematical model of a VSC is constructed. After that, the strict passivity of the VSC is proven. On the …


Electromagnetic Performance Analysis Of Multilayer Interior Pmsm With Fractional Slot Concentrated Windings For Electric Vehicle Applications, Zhiwei Zhang, Libing Zhou Jan 2015

Electromagnetic Performance Analysis Of Multilayer Interior Pmsm With Fractional Slot Concentrated Windings For Electric Vehicle Applications, Zhiwei Zhang, Libing Zhou

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents the design and analysis of fractional slot multilayer interior permanent magnet synchronous machines (PMSMs) with concentrated winding for electric vehicles applications. The major advantages of concentrated winding will be analyzed first. The significant design consideration of multilayer interior permanent magnet machines will be illustrated, as well. Finally, the advanced finite element method will be employed to verify the detailed electromagnetic performance of the proposed interior PMSMs.


Optimal Integration Of Hybrid (Wind--Solar) System With Diesel Power Plant \Newline Using Homer, Muhammad Noman Siddique, Aftab Ahmad, Muhammad Kashif Nawaz, Syed Basit Ali Bukhari Jan 2015

Optimal Integration Of Hybrid (Wind--Solar) System With Diesel Power Plant \Newline Using Homer, Muhammad Noman Siddique, Aftab Ahmad, Muhammad Kashif Nawaz, Syed Basit Ali Bukhari

Turkish Journal of Electrical Engineering and Computer Sciences

Most energy worldwide is supplied through conventional energy sources, such as thermal, hydro, and nuclear. There have been serious energy crises in the last couple of years and so it is essential to consider renewable energy sources. This paper proposes a cost-effective solution for integrating a wind--solar system with an existing diesel power plant of a grid-connected site at Taxila, Pakistan. In the case of nonavailability of power from the grid, this diesel power plant acts as a standby system. Three cases were considered in this paper: 1) using the diesel power plant during load-shedding hours; 2) assisting the system …


Active Filter Solutions In Energy Systems, Sabi̇r Rüstemli̇, Mehmet Sai̇t Cengi̇z Jan 2015

Active Filter Solutions In Energy Systems, Sabi̇r Rüstemli̇, Mehmet Sai̇t Cengi̇z

Turkish Journal of Electrical Engineering and Computer Sciences

Recent developments in power electronics have increased the usage of nonlinear loads in energy systems. With increases in the usage of semiconductor-sourced nonlinear loads, the adverse effects of harmonics-sensitive loads (e.g., protection control circuits and circuit breakers) have also increased. Generally, the negative effects of harmonics in power systems include the following: increased power losses; motor, generator, and transformer overheating; faulty operation of measurement and protection systems; lifetime shortening of electrical components; and parallel and series resonance problems. Therefore, harmonics has become a serious problem in current power electronics systems. However, harmonics can be reduced, particularly through drainage using filters. …


Variable Charge/Discharge Time-Interval Control Strategy Of Bess For Wind Power Dispatch, Wei Chai, Zheng Li, Xu Cai Jan 2015

Variable Charge/Discharge Time-Interval Control Strategy Of Bess For Wind Power Dispatch, Wei Chai, Zheng Li, Xu Cai

Turkish Journal of Electrical Engineering and Computer Sciences

A variable charge/discharge time-interval ($T_{C/D})$ control strategy of a battery energy storage system (BESS) for wind power dispatch is proposed in this paper, aiming at: 1) extending the BESS life, 2) reducing the total BESS energy loss, and 3) increasing the dispatch tracking accuracy. A multifactor life model of a large-scale BESS containing four factors, charge/discharge rate, times, $T_{C/D}$, and temperature, is developed, which has taken into account the cell series/parallel effects and BESS operational characteristics. A comprehensive evaluation system including BESS aging level (BAL), energy loss index (ELI), and tracking inaccuracy index (TII) is proposed, and the relationships between …


Low-Cost Sliding Mode Control Of Wecs Based On Dfig With Stability Analysis, Abdelhak Djoudi, Hachemi Chekireb, El Madjid Berkouk, Seddik Bacha Jan 2015

Low-Cost Sliding Mode Control Of Wecs Based On Dfig With Stability Analysis, Abdelhak Djoudi, Hachemi Chekireb, El Madjid Berkouk, Seddik Bacha

Turkish Journal of Electrical Engineering and Computer Sciences

The aim of this work is to developing sliding mode control of active and reactive stator powers produced by a wind energy conversion system (WECS), based on doubly fed induction generator (DFIG). A flux estimation model and rotor current sensor are no longer required. The controller is developed from the DFIG nonlinear-coupled model. Moreover, the global stability and the DFIG states' boundedness when our low-cost sliding mode control is applied are established analytically. It is revealed that the $(dq)$ components of the rotor flux remain near their nominal values. Our approach is validated via simulation in the case of a …


Evaluation Of Field Data And Simulation Results Of A Photovoltaic System In Countries With High Solar Radiation, Serkan Abbasoğlu, Akinola Adeyinka Babatunde Jan 2015

Evaluation Of Field Data And Simulation Results Of A Photovoltaic System In Countries With High Solar Radiation, Serkan Abbasoğlu, Akinola Adeyinka Babatunde

Turkish Journal of Electrical Engineering and Computer Sciences

The objective of this study is to examine the conformity of different simulation tools in analyzing the performance of photovoltaic (PV) systems in countries with high solar radiation. Primarily an installed system was evaluated and the results were compared with the simulation results of 3 globally known PV software tools: pvPlanner, PVsyst, and Homer. The parameters evaluated in this study are energy production, specific yield, performance ratio, and capacity factor. Detailed explanations are presented for monthly, seasonal, and annual variation of installed system data and simulation results. Northern Cyprus is selected as a case study due to high solar radiation …


A Statistical Analysis Of Wind Speed Data Using Burr, Generalized Gamma, And Weibull Distributions In Antakya, Turkey, İlker Mert, Cuma Karakuş Jan 2015

A Statistical Analysis Of Wind Speed Data Using Burr, Generalized Gamma, And Weibull Distributions In Antakya, Turkey, İlker Mert, Cuma Karakuş

Turkish Journal of Electrical Engineering and Computer Sciences

The wind energy potential of the Antakya area was statistically analyzed based 8 years of wind data sets (2002--2009). The 4-parameter Burr, 3-parameter generalized gamma, and conventional Weibull distributions were regarded as suitable statistical models for describing wind speed profiles. The suitability of the models was tested by $R^{2}$, \textit{RMSE}, chi-squared, and Kolmogorov--Smirnov analysis. According to goodness-of-fit tests, the Burr distribution was found to be more suitable than the generalized gamma or Weibull distributions for representing the actual probability of wind speed data for Antakya. Based on the capacity factors estimated by the Burr model at a hub height, the …


Transient Stability Analysis Of Vsc Hvdc Transmission With Power Injection On The Dc-Link, Agha Francis Nnachi, Josiah Munda, Dan Valentine Nicolae, Augustin Mabwe Mpanda Jan 2015

Transient Stability Analysis Of Vsc Hvdc Transmission With Power Injection On The Dc-Link, Agha Francis Nnachi, Josiah Munda, Dan Valentine Nicolae, Augustin Mabwe Mpanda

Turkish Journal of Electrical Engineering and Computer Sciences

The utilization of a DC-link transmission corridor of embedded VSC HVDC for a DC power injection from renewable energy sources to increase the power flow capability and AC network stability support is a promising technology. However, DC faults on the DC transmission line are likely to threaten the system's operation and stability, especially when the DC power injection exceeds certain limits. A DC single line-to-earth fault is the most likely fault scenario and its effect on the VSC HVDC operation will depend on the earth-loop impedance. Adding an injection point on the DC-link will reduce the earth-loop impedance, hence imposing …


Performance Improvement Of Three-Phase Self-Excited Induction Generator Feeding Induction Motor Load, Jyotirmayee Dalei, Kanungo Barada Mohanty Jan 2015

Performance Improvement Of Three-Phase Self-Excited Induction Generator Feeding Induction Motor Load, Jyotirmayee Dalei, Kanungo Barada Mohanty

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, the transient and steady-state performances of an isolated self-excited induction generator driven by a wind turbine and feeding power to a dynamic load such as a three-phase induction motor are analyzed. Mathematical modeling and simulation study of the whole system, including the wind turbine, induction generator, capacitor, pulse width modulated voltage source inverter, and dynamic load, are carried out with closed-loop voltage and frequency controller. The complete system is modeled in the stationary $d-q$ frame and validated by comparing simulation and experimental results at no-load. The same mathematical model is then used to study the transient performance …


The Integrated Control Of Fuzzy Logic And Model-Based Approach For Variable-Speed Wind Turbine, Jian Yang, Dongran Song, Hua Han, Pengsha Tong, Ling Zhou Jan 2015

The Integrated Control Of Fuzzy Logic And Model-Based Approach For Variable-Speed Wind Turbine, Jian Yang, Dongran Song, Hua Han, Pengsha Tong, Ling Zhou

Turkish Journal of Electrical Engineering and Computer Sciences

For a variable-speed wind turbine (VSWT), the primary objective of control is to maximize power generation while maintaining the desired rotor speed and avoiding equipment overloads. To fulfill the control objectives, the classical model-based control (MBC) has been widely used, which refers to two controllers: torque controller (TC) and pitch controller (PC). In this work, the drawbacks of MBC for VSWTs are studied extensively. It reveals that there are transition issues between the TC and PC, and over-speed problems under large turbulent wind when only MBC is taken. To improve the control performance of the VSWT, an integrated control solution …


Group Control And Identification Of Residential Appliances Using A Nonintrusive Method, Sunil Semwal, Munendra Singh, Rai Sachindra Prasad Jan 2015

Group Control And Identification Of Residential Appliances Using A Nonintrusive Method, Sunil Semwal, Munendra Singh, Rai Sachindra Prasad

Turkish Journal of Electrical Engineering and Computer Sciences

Identifying and controlling (ON/OFF) electrical appliance(s) from a remote location is an essential part of energy management. This motivated us to design a system that can collect the aggregate load signature from a single point, obtain the features, and finally identify the ON state of electrical appliance(s). The proposed disaggregation technique can be divided into two modules: the first part proposes an electrical installation system to disaggregate the appliance at the circuit level, whereas the second part consists of feature selection, dimension reduction, and classification algorithms. Load signatures of electrical appliances were combined with white Gaussian noise to analyze how …


Capacity Allocation Of Hybrid Solar-Wind Energy System Based On Discrete Probabilistic Method, Chengjin Ye, Minxiang Huang Jan 2015

Capacity Allocation Of Hybrid Solar-Wind Energy System Based On Discrete Probabilistic Method, Chengjin Ye, Minxiang Huang

Turkish Journal of Electrical Engineering and Computer Sciences

Complementary renewable energies like wind and solar power may be more sufficient to satisfy reliability requirements. This paper proposes a quantitative capacity allocation method of a hybrid wind and solar energy system. First, discrete probability distributions are established to model the random factors including the volatility of power outputs and the failure of components. Then a multiobjective optimization model is formulated with objectives of minimization of the total investment, the nodal voltages violating limits probability, and power supply inadequacy probability. For the purpose of fast probability computing with a satisfactory precision degree, an innovative probabilistic load flow algorithm is introduced, …


An Economic And Environmental Analysis Of Biomass-Solar Hybrid System For The Textile Industry In India, Mahalakshmi Mahadevan, Latha Salai Jan 2015

An Economic And Environmental Analysis Of Biomass-Solar Hybrid System For The Textile Industry In India, Mahalakshmi Mahadevan, Latha Salai

Turkish Journal of Electrical Engineering and Computer Sciences

This paper focuses on the design and analysis of a hybrid biomass-solar photovoltaic system for the textile industry with the goal of minimizing the cost and greenhouse gas emissions. The feasibility analysis of the hybrid system is performed based on the resource availability and the power generation potential of the existing biomass power plant near the textile plant at T.Kallupatti in Tamil Nadu, India. The power plant located at the site (9.66$^{\circ}$N, 77.79$^{\circ}$E) has an average daily global horizontal irradiance of 4.86 kWh/m$^{2}$, which has been validated through NASA Surface Meteorology and Solar Energy data. The chosen site also has …


Frequency-Adaptive Grid-Virtual-Flux Synchronization By Multiple Second-Order Generalized Integrators Under Distorted Grid Conditions, Yingjie Wang, Haiyuan Liu, Xuelong Han, Kangan Wang Jan 2015

Frequency-Adaptive Grid-Virtual-Flux Synchronization By Multiple Second-Order Generalized Integrators Under Distorted Grid Conditions, Yingjie Wang, Haiyuan Liu, Xuelong Han, Kangan Wang

Turkish Journal of Electrical Engineering and Computer Sciences

With some of the intermittent new energy and large nonlinear loads, grid voltage unbalance, harmonics, and frequency deviation are increasing year by year. The voltage source converter (VSC) is seriously affected by the various unexpected factors, and the presence of grid impedance makes the situation worse. In order to make the VSC track the nonideal grid quickly and accurately, this paper proposes a frequency-adaptive grid-virtual-flux synchronization by multiple second-order generalized integrators (MSOGI-GVFS). Key expressions of the MSOGI-GVFS and its frequency response characteristics are described in this paper. A second-order generalized integrator configured as a quadrature signal generator generates a specific-frequency …


An Improved Incremental Conductance Based Mppt Approach For Pv Modules, Mustafa Engi̇n Başoğlu, Beki̇r Çakir Jan 2015

An Improved Incremental Conductance Based Mppt Approach For Pv Modules, Mustafa Engi̇n Başoğlu, Beki̇r Çakir

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents a new maximum power point tracking (MPPT) method based on an incremental conductance (IC) algorithm, constant voltage, and look-up table approach. Convergence time, one of the indicators of MPPT quality, is considered for improving MPPT performance of photovoltaic (PV) modules. In this context, a novel hybrid MPPT approach has been proposed. This proposed method consists of three stages. In the first stage, the value of load resistance is calculated. Then the initial operation point of the PV module is determined by using the constant voltage method or look-up table approach. An IC algorithm is used in order …


Ray Tracing For Optimization Of Compound Parabolic Concentrators For Solar Collectors Of Enclosed Design, Vladimir Yurchenko, Eduard Yurchenko, Mehmet Çi̇ydem, Onat Totuk Jan 2015

Ray Tracing For Optimization Of Compound Parabolic Concentrators For Solar Collectors Of Enclosed Design, Vladimir Yurchenko, Eduard Yurchenko, Mehmet Çi̇ydem, Onat Totuk

Turkish Journal of Electrical Engineering and Computer Sciences

We present our developments in computer simulations and optimization of compound parabolic concentrators (CPCs) for solar heat collectors. Issues of both the optical and thermal optimization of CPC collectors of enclosed design are discussed. Ray tracing results for a CPC with a V-shaped absorber are presented. A range of optimal values for the apex angle of a V-shaped absorber is proposed for a CPC collector of typical design.


Supercapacitor Energy Storage Based-Upqc To Enhance Ride-Through Capability Of Wind Turbine Generators, Gangatharan Sivasankar, Velu Suresh Kumar Jan 2015

Supercapacitor Energy Storage Based-Upqc To Enhance Ride-Through Capability Of Wind Turbine Generators, Gangatharan Sivasankar, Velu Suresh Kumar

Turkish Journal of Electrical Engineering and Computer Sciences

The recent advancement in electric energy storage technologies provides an opportunity of using energy storage systems to address the issues of grid-integrated wind energy conversion systems. This paper proposes a novel configuration of a unified power quality conditioner (UPQC) with a supercapacitor-based short-term energy storage system for managing wind power intermittency during grid faults. The STATCOM-like compensation device can compensate only current related issues. The dynamic voltage restorer can compensate voltage-related issues but it can contribute only 50{\%} voltage due to converter rating limitations. Moreover, real power handling capabilities of these devices are very poor. This new UPQC scheme can …


Reliability Assessment Of A Standalone Wind-Conventional/Energy Storage System Using Probabilistic Production Simulation Method, Hossein Delavaripour, Behzad Mirzaeian Dehkordi Jan 2015

Reliability Assessment Of A Standalone Wind-Conventional/Energy Storage System Using Probabilistic Production Simulation Method, Hossein Delavaripour, Behzad Mirzaeian Dehkordi

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents a reliability evaluation technique for a small standalone system including wind and conventional resources integrated with an energy storage system. A battery bank is considered as the energy storage system. The focus in this analysis is on the effect of battery modeling and its performance on system reliability. In this way, this paper presents an accurate model for the electrochemical batteries, which takes into account all the influential characteristics of the battery related to reliability studies, such as depth of charge, efficiency of charge, and rate of discharge. The proposed reliability evaluation method is based on the …


Renewable Energy Integration In Smart Grids-Multicriteria Assessment Using The Fuzzy Analytical Hierarchy Process, Aleksandar Janjic, Suzana Savic, Lazar Velimirovic, Vesna Nikolic Jan 2015

Renewable Energy Integration In Smart Grids-Multicriteria Assessment Using The Fuzzy Analytical Hierarchy Process, Aleksandar Janjic, Suzana Savic, Lazar Velimirovic, Vesna Nikolic

Turkish Journal of Electrical Engineering and Computer Sciences

Unlike the traditional way of efficiency assessment of renewable energy sources integration, the smart grid concept is introducing new goals and objectives regarding increased use of renewable electricity sources, grid security, energy conservation, energy efficiency, and deregulated energy market. Possible benefits brought by renewable sources integration are evaluated by the degree of the approach to the ideal smart grid. In this paper, fuzzy analytical hierarchy process methodology for the integration efficiency has been proposed, taking into account the presence of multiple criteria of both qualitative and quantitative nature, different performance indicators, and the uncertain environment of the smart grid. The …


High-Speed Separation Of Anechoic Mixtures Of Speech Signals Using Fusion Of Iterative And Closed-Forms Separation Method, Mahdi Mahdikhani, Mohammad Hosein Kahaei Jan 2015

High-Speed Separation Of Anechoic Mixtures Of Speech Signals Using Fusion Of Iterative And Closed-Forms Separation Method, Mahdi Mahdikhani, Mohammad Hosein Kahaei

Turkish Journal of Electrical Engineering and Computer Sciences

We introduce the fusion of iterative and closed-forms separation (FICS) method for high-speed separation of anechoic mixed speech signals. This method is performed in two stages: 1) iterative-form separation and 2) closed-form separation. This algorithm significantly improves the separation quality simply due to incorporating only some specific frequency bins into computations. We apply the FICS method to the frequency-domain independent component analysis (ICA) to evaluate its performance in increasing the signal separation speed for anechoic mixtures. Simulation results show that for speech signals and anechoic conditions, the proposed algorithm is on average 65 times faster than ICA while preserving the …