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2017

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Articles 6001 - 6030 of 8353

Full-Text Articles in Engineering

Freeze-Drying As A Novel Biofabrication Method For Achieving A Controlled Microarchitecture Within Large, Complex Natural Biomaterial Scaffolds, Claire Brougham, Tanya J. Levingstone, Nian Shen, Gerard M. Cooney, Thomas C. Flanagan, Stefan Jockenhoevel, Fergal J. O’Brien Jan 2017

Freeze-Drying As A Novel Biofabrication Method For Achieving A Controlled Microarchitecture Within Large, Complex Natural Biomaterial Scaffolds, Claire Brougham, Tanya J. Levingstone, Nian Shen, Gerard M. Cooney, Thomas C. Flanagan, Stefan Jockenhoevel, Fergal J. O’Brien

Articles

The biofabrication of large scaffolds from natural biomaterials into complex 3D shapes with controllable microarchitecture remains a major challenge. Freeze-drying (or lyophilization) is a technique used to create bioactive scaffolds with a porous architecture and is typically only used to generate scaffolds in planar 3D geometries. Here we report the development of a new biofabrication process to form a collagen-based scaffold into a large, complex geometry which has a large height to width ratio, and a controlled porous microarchitecture. This biofabrication process was validated through the successful development of a heart valve shaped scaffold, fabricated from a collagen-glycosaminoglycan co-polymer. Notably, …

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Glass-Ceramic Optical Fiber Containing Ba2 Tisi2o8 Nanocrystals For Frequency Conversion Of Lasers, Zaijin Fang, Xusheng Xiao, Xin Wang Xin Wang, Zhijun Ma, Elfed Lewis, Gerald Farrell, Pengfei Wang, Jing Ren, Haitao Guo, Jianrong Qiu Jan 2017

Glass-Ceramic Optical Fiber Containing Ba2 Tisi2o8 Nanocrystals For Frequency Conversion Of Lasers, Zaijin Fang, Xusheng Xiao, Xin Wang Xin Wang, Zhijun Ma, Elfed Lewis, Gerald Farrell, Pengfei Wang, Jing Ren, Haitao Guo, Jianrong Qiu

Articles

A glass-ceramic optical fiber containing Ba2TiSi2O8 nanocrystals fabricated using a novel combination of the melt-in-tube method and successive heat treatment is reported for the first time. For the melt-in-tube method, fibers act as a precursor at the drawing temperature for which the cladding glass is softened while the core glass is melted. It is demonstrated experimentally that following heat treatment, Ba2TiSi2O8 nanocrystals with diameters below 10 nm are evenly distributed throughout the fiber core. Comparing to the conventional rod-in-tube method, the melt-in-tube method is superior in terms of controllability of crystallization to allow for the fabrication of low loss glass-ceramic …

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Selective Doping Of Ni2+ In Highly Transparent Glass-Ceramics Containing Nano-Spinels Znga2o4 And Zn1+Xga2−2xgexo4 For Broadband Near-Infrared Fiber Amplifiers, Zhigang Gao, Yinyao Liu, Jing Ren, Zaijin Fang, Xiaosong Lu, Elfed Lewis, Gerald Farrell, Jun Yang, Pengfei Wang Jan 2017

Selective Doping Of Ni2+ In Highly Transparent Glass-Ceramics Containing Nano-Spinels Znga2o4 And Zn1+Xga2−2xgexo4 For Broadband Near-Infrared Fiber Amplifiers, Zhigang Gao, Yinyao Liu, Jing Ren, Zaijin Fang, Xiaosong Lu, Elfed Lewis, Gerald Farrell, Jun Yang, Pengfei Wang

Articles

Selective doping of Ni2+ in octahedral sites provided by nanocrystals embedded in glass-ceramics (GCs) is crucial to the enhancement of broadband near-infrared (NIR) emission. In this work, a NIR emission with a full-width-at-half-maximum (FWHM) of 288 nm is first reported from ZnGa2O4: Ni2+ nano-spinels embedded GCs with excellent transparency. A comparison is made of the NIR luminescence properties of Ni2+ doped GCs containing ZnGa2O4, germanium-substituted ZnGa2O4 nano-spinels (Zn1+xGa2−2xGexO4), and Zn2GeO4/Li2Ge4O9 composite nanocrystals that are free of Ga3+. The results show that ZnGa2O4: Ni2+ GCs exhibit a significantly enhanced NIR emission. The incorporation of the nucleating agent TiO2 is favored in …

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Level Anticrossing Of Impurity States In Semiconductor Nanocrystals, Anvar S. Baimuratov, Ivan D. Rukhlenko, Vadim K. Turkov, Irina Ponomareva, Mikhail Yu Leonov, Tatiana S. Perova, Kevin Berwick, Alexander V. Baranov, Anatoly V. Federov Jan 2017

Level Anticrossing Of Impurity States In Semiconductor Nanocrystals, Anvar S. Baimuratov, Ivan D. Rukhlenko, Vadim K. Turkov, Irina Ponomareva, Mikhail Yu Leonov, Tatiana S. Perova, Kevin Berwick, Alexander V. Baranov, Anatoly V. Federov

Articles

The size dependence of the quantized energies of elementary excitations is an essential feature of quantum nanostructures, underlying most of their applications in science and technology. Here we report on a fundamental property of impurity states in semiconductor nanocrystals that appears to have been overlooked—the anticrossing of energy levels exhibiting different size dependencies. We show that this property is inherent to the energy spectra of charge carriers whose spatial motion is simultaneously affected by the Coulomb potential of the impurity ion and the confining potential of the nanocrystal. The coupling of impurity states, which leads to the anticrossing, can be …

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An Equivalent Circuit For Corona Discharges Caused By A Point To Plane Arrangement At Ac, Dc And Combined Voltages, Tobias Dezenzo, Thomas Betz, Andreas Schwarzbacher Jan 2017

An Equivalent Circuit For Corona Discharges Caused By A Point To Plane Arrangement At Ac, Dc And Combined Voltages, Tobias Dezenzo, Thomas Betz, Andreas Schwarzbacher

Conference papers

In this paper a new two stage equivalent circuit for corona discharges is introduced. Its aim is to fill the gap between complexity of the circuit and accurate representation of the physical properties, which underlay a corona discharge. The first stage represents the voltage distribution and the occurrence of a discharge with respect to the applied voltage. The second stage models the physical discharge behavior like ionization, number of electrons, positive and negative ions as well as their interaction. The proposed circuit is able to model the different modes of corona discharges, which is experimentally verified. The simulation results are …

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Multi-Band Antenna Array Based On Double Negative Metamaterial For Multi Automotive Applications, Mohd Jamlos, Abdulrahman Alqadami,, Imtiaz Islam, Ping Soh, Rizalman Mamat, Khairil Khairi, Adam Narbudowicz Jan 2017

Multi-Band Antenna Array Based On Double Negative Metamaterial For Multi Automotive Applications, Mohd Jamlos, Abdulrahman Alqadami,, Imtiaz Islam, Ping Soh, Rizalman Mamat, Khairil Khairi, Adam Narbudowicz

Articles

Nowadays, the demand for antennas in wireless communication system for automotive applications is rising at a rapid rate [1, 2]. Their usage includes collision avoidance system (CAS), Vehicle-to-vehicle communications, pre-crash safety systems, Global Positioning Systems (GPS), tyre pressure monitoring system (TPMS), Wireless Local Area Network (WLAN), etc. To enhance its effectiveness in these new applications, a small, multi-band, multi-functional antenna is required instead of conventional single band antennas [2, 3]. Such multifunctional antennas with favourable radiation characteristics are more practical in addressing modern antenna design requirements. However, the achievement of the above mentioned antenna’s features using conventional materials and structures …

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Uav Data For Coastal Dune Mapping, Chen Suo, Eugene Mcgovern, Alan Gilmer Jan 2017

Uav Data For Coastal Dune Mapping, Chen Suo, Eugene Mcgovern, Alan Gilmer

Conference papers

High resolution topographic maps are critical for the development of rigorous and quantitative numerical simulation landscape models. These models can inform targeted land management actions that maintain biodiversity and ecological functions. Mapping functional vegetation communities to obtain accurate distribution and population estimates is an important element of landscape models and is a challenging task which requires a considerable investment in time and resources. A recent development in surveying technologies, Unmanned Aerial Vehicles (UAV’s), also known as drones, has enabled high resolution and high accuracy ground-based data to be gathered quickly and easily on-site. The application of UAV’s represents a new …

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Strain Sensor Based On Grourd-Shaped Single-Mode-Multimode-Single-Mode Hybrid Optical Fibre Structure, Ke Tian, Gerald Farrell, Xianfan Wang, Wenlei Yang, Yifan Xin, Haidong Liang, Elfed Lewis, Pengfei Wang Jan 2017

Strain Sensor Based On Grourd-Shaped Single-Mode-Multimode-Single-Mode Hybrid Optical Fibre Structure, Ke Tian, Gerald Farrell, Xianfan Wang, Wenlei Yang, Yifan Xin, Haidong Liang, Elfed Lewis, Pengfei Wang

Articles

A fibre-optic strain sensor based on a gourd-shaped joint multimode fibre (MMF) sandwiched between two single-mode fibres (SMFs) is described both theoretically and experimentally. The cladding layers of the two MMFs are reshaped to form a hemisphere using an electrical arc method and spliced together, yielding the required gourd shape. The gourd-shaped section forms a Fabry-Perot cavity between the ends of two adjacent but noncontacting multimode fibres’ core. The effectiveness of the multimode interference based on the Fabry-Perot interferometer (FPI) formed within the multimode inter-fibre section is greatly improved resulting in an experimentally determined strain sensitivity of −2.60 pm/με over …

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Reneb - Running The European Network Of Biological Dosimetry And Physical Retrospective Dosimetry, Ulrike Kulka, Michael Abend, Liz Ainsbury, Christophe Badie, Joan-Francesc Barquinero, Leonardo Barrios, Christina Beinke, Emanuela Bortolin, Alexandra Cucu, Fiona Lyng Jan 2017

Reneb - Running The European Network Of Biological Dosimetry And Physical Retrospective Dosimetry, Ulrike Kulka, Michael Abend, Liz Ainsbury, Christophe Badie, Joan-Francesc Barquinero, Leonardo Barrios, Christina Beinke, Emanuela Bortolin, Alexandra Cucu, Fiona Lyng

Articles

Purpose: A European network was initiated in 2012 by 23 partners from 16 European countries with the aim to significantly increase individualized dose reconstruction in case of large-scale radiological emergency scenarios.

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Back Diffusion Of Electrons In Argon Subjected To Uniform Time Invariant Orthogonal Electric And Magnetic Fields, M.S. Dincer, Samet Biricik, S.S. Tezcan, S. Bektas Jan 2017

Back Diffusion Of Electrons In Argon Subjected To Uniform Time Invariant Orthogonal Electric And Magnetic Fields, M.S. Dincer, Samet Biricik, S.S. Tezcan, S. Bektas

Articles

In this study, the processes of back diffusion in Ar subjected to crossed fields are analyzed by using the Monte Carlo simulation method in the E/N range of 50 to 500 Td (1 Td = 1 × 10–17 V cm2) for 0 < B/N < 25 × 10−19 T cm3. At a given constant E/N, escape factors decrease with an increasing crossed, reduced magnetic field B/N. This reduction in the escape factor is more pronounced in the lower E/N range. Furthermore, the mean number of collisions of back scattered electrons is quite large, and at a given E/N, the mean …

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Enhanced Master/Slave Control Strategy Enabling Grid Support Services And Offshore Wind Power Dispatch In A Multi-Terminal Vsc Hvdc Transmission System, Roberto Sandano, Michael Farrell, Malabika Basu Jan 2017

Enhanced Master/Slave Control Strategy Enabling Grid Support Services And Offshore Wind Power Dispatch In A Multi-Terminal Vsc Hvdc Transmission System, Roberto Sandano, Michael Farrell, Malabika Basu

Articles

New high voltage direct current (HVDC) installations are expected to be able to provide stability support to the main synchronous networks to which they are connected. In multi-terminal HVDC (MTDC) schemes incorporating offshore wind farm this issue could be addressed by setting aside a reserve of wind energy by the curtailment of wind turbine generators (WTGs). This paper proposes a communication-less dc voltage cooperative control strategy for MTDC transmission systems. A grid side converter, the master, and a wind farm are designed to work cooperatively to maintain a stable dc link voltage, facilitating normal power dispatch orders and the provision …

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Hybrid Graphene–Copper Uwb Array Sensor For Brain Tumor Detection Via Scattering Parameters In Microwave Detection System, Mohd Aminudin Jamlos, Abdul Hafiizh Ismail, Mohd Faizal Jamlos, Adam Narbudowicz Jan 2017

Hybrid Graphene–Copper Uwb Array Sensor For Brain Tumor Detection Via Scattering Parameters In Microwave Detection System, Mohd Aminudin Jamlos, Abdul Hafiizh Ismail, Mohd Faizal Jamlos, Adam Narbudowicz

Articles

Hybrid graphene–copper ultra-wideband array sensor applied to microwave imaging technique is successfully used in detecting and visualizing tumor inside human brain. The sensor made of graphene coated film for the patch while copper for both the transmission line and parasitic element. The hybrid sensor performance is better than fully copper sensor. Hybrid sensor recorded wider bandwidth of 2.0–10.1 GHz compared with fully copper sensor operated from 2.5 to 10.1 GHz. Higher gain of 3.8–8.5 dB is presented by hybrid sensor, while fully copper sensor stated lower gain ranging from 2.6 to 6.7 dB. Both sensors recorded excellent total efficiency averaged …

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The Impact Of Sampling Frequency And Amplitude Modulation Index On Low Order Harmonics In A 3-Phase Sv-Pvm Voltage Source Inverter, Qamil Kabashi, Myzafere Limani, Nebi Caka, Milaim Zabeli Jan 2017

The Impact Of Sampling Frequency And Amplitude Modulation Index On Low Order Harmonics In A 3-Phase Sv-Pvm Voltage Source Inverter, Qamil Kabashi, Myzafere Limani, Nebi Caka, Milaim Zabeli

Turkish Journal of Electrical Engineering and Computer Sciences

Nowadays, variable speed AC motors are widely used in industry and there are many speed adjustment techniques available. In the last decade there has been a trend towards the use of space vector PWM--IGBT inverters, due to easier digital realization and better utilization of the DC bus. Every power inverter produces a total harmonic distortion (THD) on its output that causes extra losses in stator of induction motors. By eliminating a number of low order voltage/current harmonics it is possible to reduce harmonic losses (stator losses) and mechanical oscillations in general. This could be achieved by implementing filters in the …

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Neville Interpolation-Based Normal Estimation, Buse Meli̇s Özyildirim, Ulus Çevi̇k Jan 2017

Neville Interpolation-Based Normal Estimation, Buse Meli̇s Özyildirim, Ulus Çevi̇k

Turkish Journal of Electrical Engineering and Computer Sciences

Displaying useful and meaningful information from 3D data is known as volume rendering. Ray casting is one of the most frequently used direct volume rendering methods. It consists of data preparation, sampling, classification, compositing, and shading steps. Normal values are needed for efficient shading. However, 3D volumetric data are discrete and cannot be used directly for shading. Hence, the estimation of normal values, at each voxel on the surface, is needed for realistic shading. In normal estimation, the use of small voxel neighborhoods results in the staircase effect. On the other hand, the use of larger voxel neighborhoods causes loss …

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A Computer-Based Modification Solution For Old Type Of Electro-Controlled Mechanical Jacquard Looms, Mahmut Aykaç, Ercan Yildiz, Abdurrahman Oğuz Jan 2017

A Computer-Based Modification Solution For Old Type Of Electro-Controlled Mechanical Jacquard Looms, Mahmut Aykaç, Ercan Yildiz, Abdurrahman Oğuz

Turkish Journal of Electrical Engineering and Computer Sciences

In this study, we modified the old type of electro-controlled mechanical Jacquard looms for the carpet weaving industry by substituting a Jacquard controller with a modern computer running software called the "Weaving Control System", which has also been developed in the context of this study. By this modification, the Jacquard controller, which requires expensive electronic components and maintenance, has been discarded, and a contemporary computer-based solution that is easy to control and use, and cheap to install and maintain, has been employed in the place of the Jacquard controller. Even though the proposed solution has been tested on the Schleicher-type …

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A 2-D Analytical Model For Cylindrical Gate Tunnel Fet (Cg-Tfet) Based On Center Potential, Sidhartha Dash, Guru Prasad Mishra Jan 2017

A 2-D Analytical Model For Cylindrical Gate Tunnel Fet (Cg-Tfet) Based On Center Potential, Sidhartha Dash, Guru Prasad Mishra

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a 2-D cylindrical gate tunnel FET (CG-TFET) model is developed based on the potential at the center of cylinder. The center potential is obtained by Laplace solution in the cylindrical coordinate system and the accuracy is validated using a 2-D TCAD device simulator. The tunneling of charge carriers in the CG-TFET is analyzed using the center potential and the results are compared to the surface potential-based model. The drain current is formulated using the initial tunneling point and tunneling path, which further helps to obtain the threshold voltage of this model. The effect of gate engineering and …

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Full Occlusion Handling For Pedestrian Tracking Via Hybrid System, Xiaoyu Zhang, Shiqiang Hu, Huanlong Zhang, Xing Hu Jan 2017

Full Occlusion Handling For Pedestrian Tracking Via Hybrid System, Xiaoyu Zhang, Shiqiang Hu, Huanlong Zhang, Xing Hu

Turkish Journal of Electrical Engineering and Computer Sciences

Occlusion and lack of visibility even in sparse crowd scenes make it difficult to track individual pedestrians correctly and consistently, particularly in a single view. We present a novel pedestrian tracking approach that connects tracking with reidentification to locate and maintain the identity of certain people who may be occluded for a long time. First, two models are constructed. One model tracks the pedestrian and trains a classifier, while the other model reidentifies the pedestrian of interest from detection results with the trained classifier. Secondly, we design a set of transition rules for model switching. Finally, the two models work …

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A Novel Direct Torque Control Using Second Order Continuous Sliding Mode Of A Doubly Fed Induction Generator For A Wind Energy Conversion System, Zinelaabidine Boudjema, Rachid Taleb, Youcef Djeriri, Adil Yahdou Jan 2017

A Novel Direct Torque Control Using Second Order Continuous Sliding Mode Of A Doubly Fed Induction Generator For A Wind Energy Conversion System, Zinelaabidine Boudjema, Rachid Taleb, Youcef Djeriri, Adil Yahdou

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper a new robust direct torque control strategy based on second order continuous sliding mode and space vector modulation of a doubly fed induction generator integrated in a wind energy conversion system is presented. The conventional direct torque control (C-DTC) with hysteresis regulators has significant flux and torque ripples at steady-state operation and also the switching frequency varies in a wide range. The proposed DTC technique based on second order continuous sliding mode control reduces flux, current, and torque ripples. It also narrows down the switching frequency variations in induction machine control. Two different sliding surfaces such as …

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A Methodology To Include Real-Life Failure Data In The Failure Rate Estimation Of Power Distribution Systems, Mojtaba Gilvanejad, Hossein Askarian Abyaneh, Kazem Mazlumi Jan 2017

A Methodology To Include Real-Life Failure Data In The Failure Rate Estimation Of Power Distribution Systems, Mojtaba Gilvanejad, Hossein Askarian Abyaneh, Kazem Mazlumi

Turkish Journal of Electrical Engineering and Computer Sciences

Random failure rates are usually assumed as constant values in reliability calculations. In this paper, this topic is investigated using stochastic models of uncertain phenomena like lightning, cold load pickup, and overloading, which result in random failures. An algorithm is developed to estimate the random failure rates in distribution networks during their lifetime. This algorithm stochastically generates the random failures as well as sustained failures as a result of equipment wear-out state due to the aging process and finally estimates the total number of temporary/sustained failures in a period of the network lifetime. The results of applying this algorithm to …

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Experimental Evaluation And Fdtd Method For Predicting Electromagnetic Fields In The Near Zone Radiated By Power Converter Systems, Mohammed Laour, Redouane Tahmi, Christian Vollaire Jan 2017

Experimental Evaluation And Fdtd Method For Predicting Electromagnetic Fields In The Near Zone Radiated By Power Converter Systems, Mohammed Laour, Redouane Tahmi, Christian Vollaire

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents the study of conducted electromagnetic interference (EMI) currents flowing through the power cables of a DC-DC converter system and its correlation with the near field radiated from these cables. The radiated emission measurement contains a common mode (CM) and a differential mode (DM), and accurate separation of the radiated emissions of these two modes is necessary. The finite-difference time-domain (FDTD) method is used to predict the electromagnetic radiation caused by CM currents and DM currents. An experimental bench has been designed to allow access to the measurement of EMI disturbances at various sensitive places. The CM and …

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Whole Body Motion Control Of Humanoid Robots Using Bilateral Control, Emre Sariyildiz, Hakan Temeltaş Jan 2017

Whole Body Motion Control Of Humanoid Robots Using Bilateral Control, Emre Sariyildiz, Hakan Temeltaş

Turkish Journal of Electrical Engineering and Computer Sciences

This paper deals with the whole body motion control problem of humanoid robots by using automatic and bilateral control methods. Advanced motion controllers are proposed so that human daily life activities, such as walking on an uneven terrain and contacting an unknown object, can be performed. It is shown that the uncertainty of environmental impedance variation is one of the main challenging issues in the design of the automatic control systems, i.e. a humanoid robot may easily lose its stability when it contacts an unstructured environment. A novel bilateral control method is proposed for humanoid robots so as to overcome …

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Ionolab-Ray: A Wave Propagation Algorithm For Anisotropic And Inhomogeneous Ionosphere, Esra Erdem, Feza Arikan Jan 2017

Ionolab-Ray: A Wave Propagation Algorithm For Anisotropic And Inhomogeneous Ionosphere, Esra Erdem, Feza Arikan

Turkish Journal of Electrical Engineering and Computer Sciences

A high-frequency (HF) radio wave propagation model based on ray tracing for anisotropic, inhomogeneous, and time-varying ionosphere is developed to form the basis for a user-friendly modular algorithm. The algorithm IONOLAB-RAY applies the principles of ray tracing through the spherical 3D grid model of the ionosphere. The physical parameters of the ionosphere in each voxel are obtained from the ionosphere model IRI-Plas-G. The refractive index of each voxel is calculated with the Appleton-Hartree formula, which includes electron cyclotron frequency, collision frequency, and anisotropicity due to the geomagnetic field. The developed propagation algorithm allows the input of total electron content (TEC) …

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Optimal Design Of Voltage Regulators For Static Excitation System In Synchronous Generator To Reduce Shaft-Induced Voltage, Mahmoud Samieimoghaddam, Mohammad Tavakoli Bina, Masoud Aliakbar Golkar, Shokrollah Shokrikojoori Jan 2017

Optimal Design Of Voltage Regulators For Static Excitation System In Synchronous Generator To Reduce Shaft-Induced Voltage, Mahmoud Samieimoghaddam, Mohammad Tavakoli Bina, Masoud Aliakbar Golkar, Shokrollah Shokrikojoori

Turkish Journal of Electrical Engineering and Computer Sciences

Long-term shaft-induced voltage could harm synchronous generators, specifically their bearings and insulators. This paper investigates the reduction of shaft-induced voltage using both a passive filter and an active voltage regulator. An RLC circuit is used as a passive filter, and a DC-DC buck converter is used as an active voltage regulator. As a result, they remove high-frequency spikes, leading to the reduction of shaft-induced voltage. Buck converters show minimum-phase behavior and can pose as stable-casual converters. A 5 kW synchronous generator was considered for the laboratory setup in which a static excitation system using a 6-pulse thyristor rectifier supplies the …

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Intrusion Detection In Network Flows Based On An Optimized Clustering Criterion, Jaber Karimpour, Shahriar Lotfi, Aliakbar Tajari Siahmarzkooh Jan 2017

Intrusion Detection In Network Flows Based On An Optimized Clustering Criterion, Jaber Karimpour, Shahriar Lotfi, Aliakbar Tajari Siahmarzkooh

Turkish Journal of Electrical Engineering and Computer Sciences

Graph-based intrusion detection approaches consider the network as a graph and detect anomalies based on graph metrics. However, most of these approaches succumb to the cluster-based behavior of the anomalies. To resolve this problem in our study, we use flow and graph-clustering concepts to create a data set first. A new criterion related to the average weight of clusters is then defined and a model is proposed to detect attacks based on the above-mentioned criterion. Finally, the model is evaluated using a DARPA data set. Results show that the proposed approach detects the attacks with high accuracy relative to methods …

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Techno-Economic Analysis Using Different Types Of Hybrid Energy Generation For Desert Safari Camps In Uae, Ali Aziz Jan 2017

Techno-Economic Analysis Using Different Types Of Hybrid Energy Generation For Desert Safari Camps In Uae, Ali Aziz

Turkish Journal of Electrical Engineering and Computer Sciences

Remote areas in UAE are still fully powered by diesel generators. The rapid rise in the prices of petroleum products and environmental concerns have led to demand for hybrid renewable energy generators. Advances in renewable energy technologies impart further impetus to techno-economic power production. Protecting the landscape and demography of the desert by optimizing the power supply cost via an efficient hybrid power system is the key issue. Simulation results on the cross utilization of a photovoltaic/wind/battery/fuel-cell hybrid-energy source to power the off-grid living space are presented. Simultaneous exploitation of different renewable energy sources to power off-grid applications together with …

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A Steganographic Approach To Hide Secret Data In Digital Audio Based On Xor Operands Triplet Property With High Embedding Rate And Good Quality Audio, Krishna Bhowal, Debasree Chanda Sarkar, Sushanta Biswas, Partha Pratim Sarkar Jan 2017

A Steganographic Approach To Hide Secret Data In Digital Audio Based On Xor Operands Triplet Property With High Embedding Rate And Good Quality Audio, Krishna Bhowal, Debasree Chanda Sarkar, Sushanta Biswas, Partha Pratim Sarkar

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a unique and transparent data hiding algorithm based on XOR operands triplet (XOT) is proposed. In XOT, an XOR operation applied on any two members of a triplet provides the third member of the same triplet. Taking advantage of the low computational complexity and fascinating properties of the XOR operator, it is possible to embed 4-ary secret digits with negligible changes in the host digital audio. The proposed scheme has been designed to ensure that a minimum number of bit alterations happen in the host digital audio during the data hiding process, which also increases the security …

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A Neuro-Fuzzy Controller For Grid-Connected Heavy-Duty Gas Turbine Power Plants, Mohamed Iqbal Mohamed Mustafa, Joseph Xavier Rayappan, Kanakaraj Jagannathan Jan 2017

A Neuro-Fuzzy Controller For Grid-Connected Heavy-Duty Gas Turbine Power Plants, Mohamed Iqbal Mohamed Mustafa, Joseph Xavier Rayappan, Kanakaraj Jagannathan

Turkish Journal of Electrical Engineering and Computer Sciences

Frequent load fluctuation and set-point variation may affect the stability of grid-connected heavy-duty gas turbine power plants. To overcome such problems, a novel neuro-fuzzy controller is proposed in this paper for single-shaft heavy-duty gas turbines ranging from 18.2 MW to 106.7 MW. A neuro-fuzzy controller was developed using a hybrid learning algorithm and the effectiveness of the controller for all heavy-duty gas turbine plants (5, 6, 7, and 9 series) is demonstrated against load disturbance and set-point variation in a grid-connected environment. Various time domain specifications and performance index criteria of the neuro-fuzzy controller are compared with that of a …

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A Switched Current Controller With Commutation Delay Compensation For The Reduction Of Commutation Torque Ripple In Bldcm Drives, Türker Türker, Ihsan Obayes Khudhair Khudhair Jan 2017

A Switched Current Controller With Commutation Delay Compensation For The Reduction Of Commutation Torque Ripple In Bldcm Drives, Türker Türker, Ihsan Obayes Khudhair Khudhair

Turkish Journal of Electrical Engineering and Computer Sciences

The mathematical model of the equivalent circuit of a brushless DC motor switches during the operation due to commutation. This issue causes a sudden ripple in the output torque, which is called commutation torque ripple. Brushless DC motor drives suffer from commutation torque ripple, affecting the performance of the motor in practical applications. A discrete-time switched controller is proposed to reduce the commutation torque ripple in brushless DC motor drives. The proposed controller is a combination of two distinct controllers designed for two different working regions of brushless DC motors. In addition, the commutation delay is also considered in the …

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Extraction Of Geometric And Prosodic Features From Human-Gait-Speech Data For Behavioral Pattern Detection: Part I, Raj Kumar Patra, Tilendra Shishir Sinha, Ravi Prakash Dubey Jan 2017

Extraction Of Geometric And Prosodic Features From Human-Gait-Speech Data For Behavioral Pattern Detection: Part I, Raj Kumar Patra, Tilendra Shishir Sinha, Ravi Prakash Dubey

Turkish Journal of Electrical Engineering and Computer Sciences

In this work, we extract prosodic features from subjects while they are talking while walking using human-gait-speech data. These human-gait-speech data are separated into 1D data (human-speech) and 2D data (human-gait) using the adaptive-lifting scheme of wavelet transform. We carry out extraction of prosodic features from human-speech data, such as speech duration, pitch, speaking rate, and speech momentum, using five different natural languages (Hindi, Bengali, Oriya, Chhattisgarhi, and English) for the detection of behavioral patterns. These behavioral patterns form real-valued measured parameters, stored in a knowledge-based model called the human-gait-speech model. Extraction of geometrical features from human-gait data, such as …

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Temporal Preconditioners For Marching-On-In-Time-Based Time Domain Integral Equation Solvers, Hüseyi̇n Arda Ülkü Jan 2017

Temporal Preconditioners For Marching-On-In-Time-Based Time Domain Integral Equation Solvers, Hüseyi̇n Arda Ülkü

Turkish Journal of Electrical Engineering and Computer Sciences

Temporal preconditioners to stabilize the marching-on-in-time (MOT)-based time domain integral equation (TDIE) solvers are proposed. Exponentially decaying functions are used as temporal preconditioners and the proposed scheme is applied to analyze scattering from perfect electrically conducting objects using the second-order formulation. The effectiveness of the proposed scheme is demonstrated via numerical examples. It is shown that the temporal preconditioners stabilize the MOT system and the solution. In addition, the initial condition problem of TDIEs is investigated by extending the second-order formulation of the time domain electric field integral equation to the time domain magnetic and combined field integral equations.

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