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Articles 841 - 870 of 3020
Full-Text Articles in Physical Sciences and Mathematics
Low-Cost Multimode Diode-Pumped Tm:Yag And Tm:Luag Lasers, Ersen Beyatli
Low-Cost Multimode Diode-Pumped Tm:Yag And Tm:Luag Lasers, Ersen Beyatli
Turkish Journal of Electrical Engineering and Computer Sciences
We report a continuous-wave operation of Tm:YAG and Tm:LuAG lasers pumped with a low-cost, multimode AlGaAs laser diode. First, the lifetime and the absorbance behavior of 5 mm, 6 % Tm$^{3+}$-doped YAG and LuAG crystals were thoroughly investigated. A low-cost multimode 3W laser diode at 781 nm was then used as a pump source for the Tm$^{3+}$-doped laser systems. Using three different output couplers, up to 636 mW of output power was obtained from Tm:YAG laser, with a slope efficiency of 29 % at 2017 nm. The maximum output power was 637 mW in the Tm:LuAG laser, with a slope …
A Smart Wireless Sensor Network Node For Fire Detection, Wajahat Khalid, Asma Sattar, Muhammad Ali Qureshi, Asjad Amin, Mobeen Ahmed Malik, Kashif Hussain
A Smart Wireless Sensor Network Node For Fire Detection, Wajahat Khalid, Asma Sattar, Muhammad Ali Qureshi, Asjad Amin, Mobeen Ahmed Malik, Kashif Hussain
Turkish Journal of Electrical Engineering and Computer Sciences
Fires generally occur due to human carelessness and the change in environmental conditions. The uncontrolled fire results in death incidents of humans and animals as well as severe threats to the ecosystem. The preservation of the natural environment is important. The wireless sensor networks, widely used in different monitoring applications, is used in this work. For fire detection, we use flame, smoke, temperature, humidity, and light intensity sensors in our proposed network node which is low-cost, reduced-size, and power-efficient. The experiments are performed in a well-controlled real-time environment. The proposed node transmits the sensed data to the central node. The …
Optimal Dg Allocation For Enhancing Voltage Stability And Minimizing Power Loss Using Hybrid Gray Wolf Optimizer, Salah Kamel, Ayman Awad, Hussein Abdel-Mawgoud, Francisco Jurado
Optimal Dg Allocation For Enhancing Voltage Stability And Minimizing Power Loss Using Hybrid Gray Wolf Optimizer, Salah Kamel, Ayman Awad, Hussein Abdel-Mawgoud, Francisco Jurado
Turkish Journal of Electrical Engineering and Computer Sciences
High penetration of photovoltaic and wind turbine-based distributed generators (DGs) can help reduce carbon emissions which is an important goal for the whole world. DG can be used to improve the voltage stability, present generation reserve/emergency, and consequently, the system power quality can be improved. However, it is very important to select the right size and location of a DG so that the power system can increase the gained benefits of such an installation to the maximum. In this paper, a hybrid optimization technique is proposed to determine the optimal allocation of DG in the standard IEEE 33-bus radial distribution …
Method Of Limiting The Emissivity Of Wsn Networks, Tomasz Marciniak, Slawomir Bujnowski, Beata Marciniak, Zbigniew Lutowski
Method Of Limiting The Emissivity Of Wsn Networks, Tomasz Marciniak, Slawomir Bujnowski, Beata Marciniak, Zbigniew Lutowski
Turkish Journal of Electrical Engineering and Computer Sciences
Wireless sensor networks (WSNs) are a current topic of research that find usage in many applications from environmental monitoring and health protection to military applications. In this paper, analysis of the possibility of reducing the emissivity of radio sensor networks with the assumed transmission probability is discussed. This has a direct influence on power consumption by the nodes and network lifetime. A method based on introducing retransmissions on individual links creating paths between the nodes is presented. Two approaches are used in analyses, the first one being deterministic methods and the second one simulation. Both methods are used to determine …
Reusable And Interactive Classes: A New Way Of Object Composition, Saeid Masoumi, Ali Mahjur
Reusable And Interactive Classes: A New Way Of Object Composition, Saeid Masoumi, Ali Mahjur
Turkish Journal of Electrical Engineering and Computer Sciences
Separating object features from base classes is one of the popular ways of software development. Some popular programming approaches like object-oriented programming, feature-oriented programming, and aspect-oriented programming follow this approach. There are four advantages of using features: 1) Instantiability: the ability to create instances of a feature, 2) Reusability: the quality of a feature being reusable in many compositions, 3) Loosely coupled composability: the ability to compose/decompose features easily at object instantiation time (not offering new data types for compositions), and 4) Interactability: the ability of a feature to crosscut (interact with) other features inside the object. Existing approaches do …
Speech Emotion Recognition Using Semi-Nmf Feature Optimization, Surekha Reddy Bandela, T Kishore Kumar
Speech Emotion Recognition Using Semi-Nmf Feature Optimization, Surekha Reddy Bandela, T Kishore Kumar
Turkish Journal of Electrical Engineering and Computer Sciences
In recent times, much research is progressing forward in the field of speech emotion recognition (SER). Many SER systems have been developed by combining different speech features to improve their performances. As a result, the complexity of the classifier increases to train this huge feature set. Additionally, some of the features could be irrelevant in emotion detection and this leads to a decrease in the emotion recognition accuracy. To overcome this drawback, feature optimization can be performed on the feature sets to obtain the most desirable emotional feature set before classifying the features. In this paper, semi-nonnegative matrix factorization (semi-NMF) …
Evaluating The Attributes Of Remote Sensing Image Pixels For Fast K-Means Clustering, Ali̇ Sağlam, Nurdan Baykan
Evaluating The Attributes Of Remote Sensing Image Pixels For Fast K-Means Clustering, Ali̇ Sağlam, Nurdan Baykan
Turkish Journal of Electrical Engineering and Computer Sciences
Clustering process is an important stage for many data mining applications. In this process, data elements are grouped according to their similarities. One of the most known clustering algorithms is the k-means algorithm. The algorithm initially requires the number of clusters as a parameter and runs iteratively. Many remote sensing image processing applications usually need the clustering stage like many image processing applications. Remote sensing images provide more information about the environments with the development of the multispectral sensor and laser technologies. In the dataset used in this paper, the infrared (IR) and the digital surface maps (DSM) are also …
A Crowdsensing-Based Framework For Urban Air Quality Decision Support, Hasna Elalaoui Elabdallaoui, Abdelaziz Elfazziki, Jamal Ouarzazi, Fatima Zohra Ennaji, Mohamed Sadgal
A Crowdsensing-Based Framework For Urban Air Quality Decision Support, Hasna Elalaoui Elabdallaoui, Abdelaziz Elfazziki, Jamal Ouarzazi, Fatima Zohra Ennaji, Mohamed Sadgal
Turkish Journal of Electrical Engineering and Computer Sciences
Air pollution is considered a major health problem in urban areas. Small sensor technology integrated with smart phones can be widely used to collect air quality information in real time using mobile applications. By applying the concept of crowdsensing, citizens and authorities can be aware of exposure to pollution during their daily activities in urban areas. This paper describes an on-road air quality monitoring and control approach based on the crowdsensing paradigm. In addition to collecting air pollution data, we are exploring the possibility of using this technology to effectively detect critical situations and redistribute all information through a proactive …
Rough Fuzzy Cuckoo Search For Triclustering Microarray Gene Expression Data, Swathypriyadharsini Palaniswamy, Premalatha K
Rough Fuzzy Cuckoo Search For Triclustering Microarray Gene Expression Data, Swathypriyadharsini Palaniswamy, Premalatha K
Turkish Journal of Electrical Engineering and Computer Sciences
Analyzing time series microarray gene expression data is a computational challenge due to its three-dimensional characteristics. Triclustering techniques are applied to three-dimensional data for mining similarly expressed genes under a subset of conditions and time points. In this work, a novel rough fuzzy cuckoo search algorithm is proposed for triclustering genes across samples and time points simultaneously. By applying the upper and lower approximation of rough set theory and the objective function of fuzzy k-means, rough fuzzy k-means was incorporated into a cuckoo search to handle the uncertainty of the data. The proposed method was applied to three real-life time …
Performance Evaluation Of Webrtc-Based Online Consultation Platform, Ergün Alperay Tarim, Hüseyi̇n Cumhur Teki̇n
Performance Evaluation Of Webrtc-Based Online Consultation Platform, Ergün Alperay Tarim, Hüseyi̇n Cumhur Teki̇n
Turkish Journal of Electrical Engineering and Computer Sciences
Information technologies give patients the opportunity to communicate with medical professionals remotely. Telemedicine uses these technologies to provide advanced healthcare and medical services. We present a medical online consultation application based on Web Real-Time Communications (WebRTC) technology enabling chat, audio, and video calls. Communication architecture and protocols of the application are explained in detail. Additionally, the user interface of the application is shown via performed calls. The application is tested and evaluated on different network connections (3G, 4G, local, and DSL) and different browsers and mobile operating systems (Android, Chrome, Firefox, Internet Explorer, iOS, Opera, Safari). During calls, communication quality …
On The Output Regulation For Linear Fractional Systems, Jesus Alberto Meda Campana, Elba Cinthya Garcia Estrada, Julio Cesar Gomez Mancilla, Jose De Jesus Rubio Avila, Mario Ricardo Cruz Deviana, Ricardo Tapia Herrera
On The Output Regulation For Linear Fractional Systems, Jesus Alberto Meda Campana, Elba Cinthya Garcia Estrada, Julio Cesar Gomez Mancilla, Jose De Jesus Rubio Avila, Mario Ricardo Cruz Deviana, Ricardo Tapia Herrera
Turkish Journal of Electrical Engineering and Computer Sciences
In this work, the regulation problem is extended to the field of fractional-order linear systems considering the Caputo fractional derivative. The regulation equations are obtained on the basis of the Francis equations. It is also shown that the linear fractional regulator exists at $t=0$ only if the order of the plant is not greater than the order of the reference system.
Adaptive Iir Filter Design Using Self-Adaptive Search Equation Based Artificial Bee Colony Algorithm, Burhanetti̇n Durmuş, Gürcan Yavuz, Doğan Aydin
Adaptive Iir Filter Design Using Self-Adaptive Search Equation Based Artificial Bee Colony Algorithm, Burhanetti̇n Durmuş, Gürcan Yavuz, Doğan Aydin
Turkish Journal of Electrical Engineering and Computer Sciences
Infinite impulse response (IIR) system identification problem is defined as an IIR filter modeling to represent an unknown system. During a modeling task, unknown system parameters are estimated by metaheuristic algorithms through the IIR filter. This work deals with the self-adaptive search-equation-based artificial bee colony (SSEABC) algorithm that is adapted to optimal IIR filter design. SSEABC algorithm is a recent and improved variant of artificial bee colony (ABC) algorithm in which appropriate search equation is determined with a self-adaptive strategy. Moreover, the success of the SSEABC algorithm enhanced with a competitive local search selection strategy was proved on benchmark functions …
Improving Side Lobe Level Of X-Band Microstrip Rotman Lens Utilizing Nonuniform Distribution Of Output Ports, Ehsan Zareian Jahromi, Raheleh Basiri, Parvin Salehi, Hamidreza Karami
Improving Side Lobe Level Of X-Band Microstrip Rotman Lens Utilizing Nonuniform Distribution Of Output Ports, Ehsan Zareian Jahromi, Raheleh Basiri, Parvin Salehi, Hamidreza Karami
Turkish Journal of Electrical Engineering and Computer Sciences
A new microstrip Rotman lens with enhanced side lobe level (SLL) is proposed for X-band applications. A proper nonuniform distribution of the initial width of output ports is considered to improve the SLL. The benefit of SLL improvement is not based on using additional attenuators or amplifiers at the output ports. Moreover, an analytical background is presented to investigate the resulting SLL of the proposed structure. The advantage of SLL enhancement is obtained at all noncorner scan angles considering 10 GHz operating frequency. As the middle input port is excited, more than 3 dB of SLL enhancement is achieved at …
A Novel And Unified Approach For Averaged Channel Capacity And Averagedeffective Capacity Analyses Of Diversity Combining And Multihop Transmissionschemes In Flat Fading Environments, Ferkan Yilmaz, Mohamed-Slim Alouini
A Novel And Unified Approach For Averaged Channel Capacity And Averagedeffective Capacity Analyses Of Diversity Combining And Multihop Transmissionschemes In Flat Fading Environments, Ferkan Yilmaz, Mohamed-Slim Alouini
Turkish Journal of Electrical Engineering and Computer Sciences
n this paper, we introduce an Lp -norm aggregation to present a signal-to-noise ratio expression unified not only for such diversity combining schemes as equal-gain combining, maximal-ratio combining, and selection combining, but also for such transmission techniques as multihop transmission. Accordingly, we propose two moment-generating function-based approaches that both respectively unify the exact analyses of the averaged channel capacity and averaged effective capacity over generalized fading channels with respect to the diversity combining and multihop transmission schemes. Finally, the mathematical formalism is illustrated by numerical special cases and verified by simulations.
Determination Of Distance Between Dc Traction Power Centers In A 1500-V Dc Subway Line With Artificial Intelligence Methods, Mehmet Taci̇ddi̇n Akçay, İlhan Kocaarslan
Determination Of Distance Between Dc Traction Power Centers In A 1500-V Dc Subway Line With Artificial Intelligence Methods, Mehmet Taci̇ddi̇n Akçay, İlhan Kocaarslan
Turkish Journal of Electrical Engineering and Computer Sciences
The electrification system in rail systems is designed with regard to the operating data and design parameters. While the electrification system is formed, the minimum voltage rating that the traction force requires during the operation needs to be provided. The highest value of the voltage drop occurring on the line is determined by the distance between power centers. This value needs to be kept within certain limits for the continuity of operation. In this study, the determination of the distance between DC traction power centers for a 1500-V DC-fed rail system is done by means of the adaptive neuro-fuzzy inference …
A Coordinated Dc Voltage Control Strategy For Cascaded Solid State Transformer With Star Configuration, Zhendong Ji, Yichao Sun, Cheng Jin, Jianhua Wang, Jianfeng Zhao
A Coordinated Dc Voltage Control Strategy For Cascaded Solid State Transformer With Star Configuration, Zhendong Ji, Yichao Sun, Cheng Jin, Jianhua Wang, Jianfeng Zhao
Turkish Journal of Electrical Engineering and Computer Sciences
Cascaded solid-state transformer (SST) can be directly connected to the high-voltage distribution grid, and it has broad applications in the future smart grid, traction locomotive, and renewable energy integration. However, the reliability of the cascaded SST is seriously influenced by the DC voltage and power imbalance issues with this configuration. This paper presents a coordinated DC voltage control strategy for cascaded SST with star configuration, in which the average DC voltage and the balancing DC voltage are controlled separately without current sensors in dual active bridge (DAB) modules. This strategy not only reduces the cost and the complexity of the …
Approximation Of Planar Curves, Malik Zawwar Hussain, Ayesha Shakeel, Maria Hussain
Approximation Of Planar Curves, Malik Zawwar Hussain, Ayesha Shakeel, Maria Hussain
Turkish Journal of Electrical Engineering and Computer Sciences
In the present article, we have developed the $G^{2}$-approximation scheme for planar curves arising in science, engineering, computer-aided design, computer-aided manufacturing, and many other fields. The obtained results reveal that the proposed method is a significant addition to the approximation of planar curves. The method is illustrated using different numerical examples. The smaller absolute error confirms the applicability and efficiency of the proposed method.
Cost-Effective Telemetry For Energy Network Of An Electricity Distribution Company: Part I, Asim Zaheer Ud Din, Yasar Ayaz, Mian Ilyas Ahmad Ahmad, Momena Hasan, Salman Masaud, Naveed Muhammad
Cost-Effective Telemetry For Energy Network Of An Electricity Distribution Company: Part I, Asim Zaheer Ud Din, Yasar Ayaz, Mian Ilyas Ahmad Ahmad, Momena Hasan, Salman Masaud, Naveed Muhammad
Turkish Journal of Electrical Engineering and Computer Sciences
We present a novel application of radio frequency wireless mesh network and general packet radio service technologies in a telemetry solution to measure power flow in the energy network of an electricity distribution company. The telemetry solution utilizes some selected circuits of grid stations and calculates total power consumed, total power imported, and total power exported by the distribution company. The selection of circuits for sensors installation is the key for reducing solution cost as compared to the case when sensors are installed on all the power output points. The framework involves installation of specially developed energy sensors (smart energy …
Understanding Attribute And Social Circle Correlation In Social Networks, Pranav Nerurkar, Madhav Chandane, Sunil Bhirud
Understanding Attribute And Social Circle Correlation In Social Networks, Pranav Nerurkar, Madhav Chandane, Sunil Bhirud
Turkish Journal of Electrical Engineering and Computer Sciences
Social circles, groups, lists, etc. are functionalities that allow users of online social network (OSN) platforms to manually organize their social media contacts. However, this facility provided by OSNs has not received appreciation from users due to the tedious nature of the task of organizing the ones that are only contacted periodically. In view of the numerous benefits of this functionality, it may be advantageous to investigate measures that lead to enhancements in its efficacy by allowing for automatic creation of customized groups of users (social circles, groups, lists, etc). The field of study for this purpose, i.e. creating coarse-grained …
Investigating The Occurrence Mechanism Of Cytokine-Like Formations By The Electromagnetic Approach, Cahi̇t Canbay, Özgün Palak, Aydoğa Kallem
Investigating The Occurrence Mechanism Of Cytokine-Like Formations By The Electromagnetic Approach, Cahi̇t Canbay, Özgün Palak, Aydoğa Kallem
Turkish Journal of Electrical Engineering and Computer Sciences
This study aims to elucidate the production mechanism of cytokine-like formations secreted from T cells and similar cells by electromagnetic modeling techniques. Three Hertz dipole antennas polarized in arbitrary directions were placed without touching each other at the center of spherical T-cell models to test the Canbay hypothesis about the formation mechanism of cytokines (CHAFMOC) on T-cell surfaces. A dielectrophoretic force field was created within the gelatin layer of the T-cell model. The prepared control and electromagnetically stimulated T-cell model samples were incubated in water in a glass container in a Faraday cage for the specified period and then photographed. …
Electron Energy Loss Spectroscopy Simulation By A Frequency Domain Surface Integral Equation Solver, İsmai̇l Enes Uysal
Electron Energy Loss Spectroscopy Simulation By A Frequency Domain Surface Integral Equation Solver, İsmai̇l Enes Uysal
Turkish Journal of Electrical Engineering and Computer Sciences
Plasmonic nanoparticles have been mostly studied using conventional light sources. Recently, electron energy loss spectroscopy (EELS) has started to be used to analyze plasmonic nanoparticles where incident electromagnetic fields are created by swift electrons. To accurately simulate EELS experiments, several numerical methods have been adapted. In this paper, a frequency domain surface integral equation (FDSIE) solver is modified to simulate EELS for plasmonic nanoparticles of gold and silver. Accuracy and versatility of the proposed FDSIE solver are shown by several numerical examples and compared to existing numerical, analytical, and experimental results.
Outage Probability Analysis And Adaptive Combiner For Multiuser Multipolarized Antenna Systems, Abdul Hai Muzammil Mohammed, Muhammad Moinuddin, Ubaid Muhsen Al-Saggaf, Ahmad Kamal Hassan
Outage Probability Analysis And Adaptive Combiner For Multiuser Multipolarized Antenna Systems, Abdul Hai Muzammil Mohammed, Muhammad Moinuddin, Ubaid Muhsen Al-Saggaf, Ahmad Kamal Hassan
Turkish Journal of Electrical Engineering and Computer Sciences
In this paper, we characterize the performance metrics of a multiuser multipolarized antenna system in a Rayleigh fading channel. We start by formulating a downlink system model that features a multiuser scenario in the presence of additive noise and a multipolarized antenna system; this is followed by evaluation of the outage probability in closed form. This is done by deriving the cumulative distribution function (CDF) of the signal-to-interference-plusnoise ratio using the approach of the ratio of indefinite quadratic forms. We thereby characterize the gradient of this CDF with respect to the combining vectors. Eventually, we obtain the optimum combining vectors …
Bow-Tie-Shaped Wideband Conformal Antenna With Wide-Slot For Gps Application, Ratikanta Sahoo, Damera Vakula
Bow-Tie-Shaped Wideband Conformal Antenna With Wide-Slot For Gps Application, Ratikanta Sahoo, Damera Vakula
Turkish Journal of Electrical Engineering and Computer Sciences
In this article, a novel wideband cylindrical conformal antenna using a wide slot in the ground plane is proposed. A bow-tie-shaped patch antenna is designed for Global Positioning System applications. The bandwidth of the antenna is improved by using a similar bow-tie-shaped slot in the ground plane with a larger dimension. The bandwidth is further enhanced by introducing a dumbbell-shaped slit in the patch. The antenna is fed by a 50-$ \Omega $ microstrip line. The proposed planar antenna is printed on a ground plane of size 0.5$ \lambda $ mm$ \times $ 0.5$ \lambda $ mm, where $ \lambda …
Three-Channel Control Architecture For Multilateral Teleoperation Under Time Delay, Uğur Tümerdem
Three-Channel Control Architecture For Multilateral Teleoperation Under Time Delay, Uğur Tümerdem
Turkish Journal of Electrical Engineering and Computer Sciences
Multilateral teleoperation is an extension of bilateral/haptic teleoperation framework to multiple operators/robots and finds applications in haptic training. As in bilateral teleoperation, time delay is an important problem, and stability and transparency, which quantifies the performance of the teleoperation system, are critical in the design of multilateral control systems. This paper proposes a novel three-channel-based multilateral control architecture with damping injection to guarantee delay-independent L2 stability and high transparency in multilateral teleoperation systems. The theoretical and computational analyses are verified with experiment results.
Pipelined Adders For Ultralow-Power Wearables, Mansi Jhamb, Tejaswini Dhall, Tamish Verma, Hinduja Puri
Pipelined Adders For Ultralow-Power Wearables, Mansi Jhamb, Tejaswini Dhall, Tamish Verma, Hinduja Puri
Turkish Journal of Electrical Engineering and Computer Sciences
For continuous real-time monitoring of personal health, wearable devices are indispensable. The constraintsof cost, power consumption, and limited device dimensions are the critical issues which need to be handled carefullywhile designing these battery-powered devices. The wearables employ high-end processors dedicated for complex signalprocessing. The core of every digital signal processor is its data path. The arithmetic units like adders constitute thecore of data path and addressing unit. This work proposes a novel low-complexity asynchronous pipelined adder. Theproposed design guarantees great savings in power and latency, which makes it a suitable candidate for low-power high-speed sophisticated wearables. The proposed design consumes …
Contribution Of Artificial Proprioception On A Dynamic Finger Flexion Task, Mehdi Hojatmadani, Evren Samur
Contribution Of Artificial Proprioception On A Dynamic Finger Flexion Task, Mehdi Hojatmadani, Evren Samur
Turkish Journal of Electrical Engineering and Computer Sciences
There has been a considerable effort to provide sensory feedback for myoelectric prostheses. Among the solutions provided in the literature, sensory substitution is an easy and cost-effective way to provide feedback through different sensory modalities at different locations on the body. In this study, we evaluate the effect of sensory substitution of force and position feedback on a two-degree-of-freedom dynamic finger flexion task. For this purpose, a new methodology and an experimental setup are developed. The experimental methodology is based on the "strength-dexterity test", working on the principle of buckling of compression springs. The experimental setup comprises a haptic interface, …
Thyristor-Based "Phase Hopping" Frequency Conversion Technique, Zhenwang Xu, Jiarui Zhang, Yuchun Yi, Cheng Chen, Jiaqi Yu, Wei Mei, Daiwei Feng
Thyristor-Based "Phase Hopping" Frequency Conversion Technique, Zhenwang Xu, Jiarui Zhang, Yuchun Yi, Cheng Chen, Jiaqi Yu, Wei Mei, Daiwei Feng
Turkish Journal of Electrical Engineering and Computer Sciences
This study proposes a new AC/AC "phase hopping" frequency conversion method based on the analyses of the disadvantages of the conventional cosine wave-crossing method. The advantages of this new method include no circulating current, no dead time, and an output frequency close to the power frequency. This study also introduces the basic principles of the "phase hopping" method and analyzes these principles combined with the voltage phase-changing comparison to that of the cosine wave-crossing method. The "phase hopping" principles are used to analyze the generation of thyristor trigger pulses, including the generation time and duration. A simulation is conducted in …
Optimized Modeling Of Ni-Mh Batteries Primarily Based On Taguchi Approach And Evaluation Of Used Ni-Mh Batteries, Hani Muhsen, Ahmad Al-Muhtady
Optimized Modeling Of Ni-Mh Batteries Primarily Based On Taguchi Approach And Evaluation Of Used Ni-Mh Batteries, Hani Muhsen, Ahmad Al-Muhtady
Turkish Journal of Electrical Engineering and Computer Sciences
This paper aims to generate an optimized model of the Ni-MH battery based on the Taguchi method and it further aims to evaluate used Ni-MH batteries that served in hybrid electric vehicles and electric vehicles. The status of twelve used Ni-MH batteries is studied to determine their usefulness after their life cycle in automotive applications. The status of used batteries is evaluated by investigating their state of charge, remaining useful life, and degradation in performance. Accordingly, the tested batteries are classified into four categories and they are proposed to serve in different applications. The novelty of the work lies in …
Evaluation Of Power System Robustness In Order To Prevent Cascading Outages, Farnaaz Hajbani, Heresh Seyedi, Kazem Zare
Evaluation Of Power System Robustness In Order To Prevent Cascading Outages, Farnaaz Hajbani, Heresh Seyedi, Kazem Zare
Turkish Journal of Electrical Engineering and Computer Sciences
Power system robustness against overload condition is a challenging issue in the fields of power system planning and operation. In this paper, two indices are proposed to evaluate power system robustness. The proposed indices are used to identify critical lines whose failure is due to overload, leading the power system to cascading outages and blackout. The first proposed index is a linear index. The second index is based on graph theory metrics. To prevent cascading outages, system robustness is calculated for all N-1 and N-2 contingencies. The lines whose outages lead to the smallest robustness values are considered as critical …
A Fuzzy Model Of Directional Relationships From The Phi-Descriptor, Mohammad Naeem, Nasir Ahmad, Sahib Khan, Asma Gul
A Fuzzy Model Of Directional Relationships From The Phi-Descriptor, Mohammad Naeem, Nasir Ahmad, Sahib Khan, Asma Gul
Turkish Journal of Electrical Engineering and Computer Sciences
Directional spatial relationships are a category of spatial relationships and have applications in the fields of image processing, geographic information systems, natural language processing, and robot navigation. They can be directly extracted from images or can be interpreted from a type of image descriptors called the relative position descriptors. Examples of relative position descriptors are the angle histogram, the force histogram, and the recently proposed phi-descriptor. So far, fuzzy models of directional spatial relationships from the angle histogram and force histograms have been proposed in the literature. These include the compatibility method, the aggregation method, and the method of effective …