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2018

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Articles 13111 - 13140 of 13644

Full-Text Articles in Physical Sciences and Mathematics

Ultra Low-Power Dc Voltage Limiter For Rfid Application In 0.18-Μm Cmostechnology, Rezvan Dastanian, Sajad Nejadhasan Jan 2018

Ultra Low-Power Dc Voltage Limiter For Rfid Application In 0.18-Μm Cmostechnology, Rezvan Dastanian, Sajad Nejadhasan

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a low-power DC voltage limiter is designed for radio frequency identification tags. In this design, the low-power bandgap reference (BGR) circuit, which is insensitive to temperature, and also the comparator are used for the voltage limiter circuit. To make the I-V curve approach the ideal one, four inverter stages are employed to the output of the comparator. The structure of the BGR and comparator use only MOSFET transistors that work in subthreshold region when the limiter is inactive. These two blocks have power consumption of 220 pW and 1300 pW, respectively. The limited output voltage is 1.5 …

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Model-Free Approach Based On Intelligent Pd Controller For Vertical Motionreduction In Fast Ferries, Mounia Ticherfatine, Zhu Qidan Jan 2018

Model-Free Approach Based On Intelligent Pd Controller For Vertical Motionreduction In Fast Ferries, Mounia Ticherfatine, Zhu Qidan

Turkish Journal of Electrical Engineering and Computer Sciences

A new model-free approach was investigated to control two moving aps and a T-foil of a fast ferry traveling in the head sea. Considered as a highly perturbed system, fast ferries in sea waves suffer from the undesirable effects of pitch and heave motions causing severe vertical accelerations that lead to the discomfort of passengers who then experience seasickness. To appropriately control this multivariable system, a model-free control strategy was adopted. An augmented PD controller with compensating terms resulting from an online identification of an ultralocal model of the system was designed. Relying only on input{output data and using online …

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Energy-Efficient And Reliable Data Collection In Wireless Sensor Networks, Deepa Puneeth, Nishanth Joshi, Pradeep Kumar Atrey, Muralidhar Kulkarni Jan 2018

Energy-Efficient And Reliable Data Collection In Wireless Sensor Networks, Deepa Puneeth, Nishanth Joshi, Pradeep Kumar Atrey, Muralidhar Kulkarni

Turkish Journal of Electrical Engineering and Computer Sciences

Ensuring energy efficiency, data reliability, and security is important in wireless sensor networks (WSNs). A combination of variants from the cryptographic secret sharing technique and the disjoint multipath routing scheme is an effective strategy to address these requirements. Although Shamir's secret sharing (SSS) provides the desired reliability and information-theoretic security, it is not energy efficient. Alternatively, Shamir's ramp secret sharing (SRSS) provides energy efficiency and data reliability, but is only computationally secure. We argue that both these approaches may suffer from a compromised node (CN) attack when a minimum number of nodes is compromised. Hence, we propose a new scheme …

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Indoor Localization Of Wireless Emitter Using Direct Position Determination And Particle Swarm Optimization, Saeid Hassanhosseini, Mohammad Reza Taban, Jamshid Abouei Jan 2018

Indoor Localization Of Wireless Emitter Using Direct Position Determination And Particle Swarm Optimization, Saeid Hassanhosseini, Mohammad Reza Taban, Jamshid Abouei

Turkish Journal of Electrical Engineering and Computer Sciences

Many methods are introduced to accomplish determining the position of emitters with respect to known-position receivers in indoor localizations. Among them, the direct position determination (DPD) approach advocates using the received signals by all the base stations together in order to estimate the locations in a single step. However, DPD is not very accurate due to the use of a gridding area, the effect of noise, and the multipath phenomenon. In order to improve the DPD performance, we derive an analytic model based on weighted least square estimation that uses simultaneously the effect of delay, Doppler, attenuation, and angle of …

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Choice Of Battery Energy Storage For A Hybrid Renewable Energy System, Kusum Lata Tharani, Ratna Dahiya Jan 2018

Choice Of Battery Energy Storage For A Hybrid Renewable Energy System, Kusum Lata Tharani, Ratna Dahiya

Turkish Journal of Electrical Engineering and Computer Sciences

There are certain unelectrified villages across the Indian subcontinent where providing supply through the grid is difficult due to forest cover or mountainous terrain. The most feasible option is to provide off-grid electrification through renewable energy resources such as solar or wind energy. These intermittent sources do not promise a 24 $\times $ 7 supply system. Thus, along with solar or wind energy systems, it becomes important to use a renewable resource, such as biomass, which is available in abundance in rural areas. The need for battery energy storage becomes mandatory in order to store the surplus energy produced by …

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Brain-Computer Interface: Controlling A Robotic Arm Using Facial Expressions, Humaira Nisar, Hong-Way Khow, Kim Ho Yeap Jan 2018

Brain-Computer Interface: Controlling A Robotic Arm Using Facial Expressions, Humaira Nisar, Hong-Way Khow, Kim Ho Yeap

Turkish Journal of Electrical Engineering and Computer Sciences

The aim of this paper is to develop a brain-computer interface (BCI) system that can control a robotic arm using EEG signals generated by facial expressions. The EEG signals are acquired using a neurosignal acquisition headset. The robotic arm consists of a 3-D printed prosthetic hand that is attached to a forearm and elbow made of craft wood. The arm is designed to make four moves. Each move is controlled by one facial expression. Hence, four different EEG signals are used in this work. The performance of the BCI robotic arm is evaluated by testing it on 10 subjects. Initially …

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Supercapacitor Utilization For Power Smoothening And Stability Improvement Of Ahybrid Energy System In A Weak Grid Environment, Rahul Sharma, Sathans Suhag Jan 2018

Supercapacitor Utilization For Power Smoothening And Stability Improvement Of Ahybrid Energy System In A Weak Grid Environment, Rahul Sharma, Sathans Suhag

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a novel control scheme based on the application of a supercapacitor (SC) is proposed for power smoothening and stability improvement of a hybrid energy system (HES) in weak grid conditions. The basic property of fast charging/discharging of the SC is utilized to design the proposed control. In weak grid conditions, the control structure is proposed for power smoothening and DC link voltage regulation with the help of the SC. Moreover, the stability is increased, ripples in voltage are reduced, there is fast dynamic response, and oscillations are damped out under different conditions. In conventional control, voltage controller …

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Highly Accurate And Sensitive Short Read Aligner, Mehmet Yağmur Gök, Sezer Gören Uğurdağ, Cem Ünsalan, Mahmut Şami̇l Sağiroğlu Jan 2018

Highly Accurate And Sensitive Short Read Aligner, Mehmet Yağmur Gök, Sezer Gören Uğurdağ, Cem Ünsalan, Mahmut Şami̇l Sağiroğlu

Turkish Journal of Electrical Engineering and Computer Sciences

Next-generation sequencing generates large numbers of short reads from DNA. This makes it difficult to process and store. Therefore, efficient sequence alignment and mapping techniques are needed in bioinformatics. Alignment and mapping are the basic steps involved in genetic data analysis. The Smith-Waterman (SW) algorithm, a well-known dynamic programming algorithm, is often used for this purpose. In this work, we propose to utilize Phred quality scores in Gotoh's affine gap model to increase the accuracy and sensitivity of the SW algorithm. Hardware platforms such as FPGAs and GPUs are commonly used to solve computationally expensive problems. In this work, a …

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A Novel Solution In The Simultaneous Deep Optimization Of Rgb-D Camera Calibration Parameters Using Metaheuristic Algorithms, Amir Safaei, Saeid Fazli Jan 2018

A Novel Solution In The Simultaneous Deep Optimization Of Rgb-D Camera Calibration Parameters Using Metaheuristic Algorithms, Amir Safaei, Saeid Fazli

Turkish Journal of Electrical Engineering and Computer Sciences

This article presents a novel method for estimating 19 parameters of RGB and depth camera calibration simultaneously. The proposed algorithm is based on applying metaheuristic methods for deep optimization and estimating all parameters of intrinsic, extrinsic, and lens distortions of cameras. This paper compares four metaheuristic algorithms, i.e. a genetic algorithm, particle swarm optimization, the colonial competitive algorithm, and the shuffled frog leaping algorithm, with a numerical algorithm called singular value decomposition. The proposed method does not need the initial estimation for optimization and it can avoid being trapped in local minima. By using nondirect estimation, we achieve middle computing …

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Qrmw: Quantum Representation Of Multi Wavelength Images, Engi̇n Şahi̇n, İhsan Yilmaz Jan 2018

Qrmw: Quantum Representation Of Multi Wavelength Images, Engi̇n Şahi̇n, İhsan Yilmaz

Turkish Journal of Electrical Engineering and Computer Sciences

In this study, we propose quantum representation of multiwavelength images (QRMW) that gives preparation and retrieving procedures of quantum images. The proposed QRMW model represents multichannel and $2^{n}\times 2^{m}$ images. Moreover, we present image comparison and some image operations based on the QRMW model. Comparing our model with the models in the literature, the QRMW model has less time complexity. It also uses fewer qubits than existing models in the literature.

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Nonintrusive Identification Of Residential Appliances Using Harmonic Analysis, Srdjan Djordjevic, Milan Simic Jan 2018

Nonintrusive Identification Of Residential Appliances Using Harmonic Analysis, Srdjan Djordjevic, Milan Simic

Turkish Journal of Electrical Engineering and Computer Sciences

The role of nonintrusive load monitoring (NILM) is to identify the operating schedules of individual appliances and their power consumption from single-point electrical measurements. This paper discusses appliance load monitoring based on the harmonic analysis of the steady-state current, which is specifically suited for identification of nonlinear appliances. The existing harmonic-based NILM methods have limited applicability due to the fact that their complexity increases exponentially with the number of target appliances. In order to overcome this problem, this study suggests the use of the step changes of current harmonic phasors as a feature for appliance detection. The key benefit of …

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Insider Threat Detection Of Adaptive Optimization Dbn For Behavior Logs, Jiange Zhang, Yue Chen, Ankang Ju Jan 2018

Insider Threat Detection Of Adaptive Optimization Dbn For Behavior Logs, Jiange Zhang, Yue Chen, Ankang Ju

Turkish Journal of Electrical Engineering and Computer Sciences

For the problems of insider threats such as great harm due to damage and resultant loss, difficulty in extracting abnormal behavior features of insiders because of transparency and concealment, and low detection rate, an insider threat detection model using adaptive optimization DBN for behavior logs is put forward. The model carries out deep learning based on the integrated and normalized behavior logs to fully learn normal and abnormal behavior features of insiders to form optimal representations of the behavior features of insiders. The experimental results show that the multiple-hidden-layer deep learning model can fully learn the behavior features of insiders, …

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Relation Extraction Via One-Shot Dependency Parsing On Intersentential, Higher-Order, And Nested Relations, Gözde Gül Şahi̇n, Erdem Emekli̇gi̇l, Seçi̇l Arslan, Onur Ağin, Gülşen Eryi̇ği̇t Jan 2018

Relation Extraction Via One-Shot Dependency Parsing On Intersentential, Higher-Order, And Nested Relations, Gözde Gül Şahi̇n, Erdem Emekli̇gi̇l, Seçi̇l Arslan, Onur Ağin, Gülşen Eryi̇ği̇t

Turkish Journal of Electrical Engineering and Computer Sciences

Despite the emergence of digitalization, people still interact with institutions via traditional means such as submitting free formatted petitions, orders, or applications. These noisy documents generally consist of complex relations that are nested, higher-order, and intersentential. Most of the current approaches address extraction of only sentence-level and binary relations from grammatically correct text and generally require high-level linguistic features coming from preprocessors such as a parts-of-speech tagger, chunker, or syntactic parser. In this article, we focus on extracting complex relations in order to automate the task of understanding user intentions. We propose a novel language-agnostic and noise-immune approach that does …

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Optimizing Fpga-Based Cnn Accelerator For Energy Efficiency With An Extended Roofline Model, Sayed Omid Ayat, Mohamed Khalil-Hani, Ab Al-Hadi Ab Rahman Jan 2018

Optimizing Fpga-Based Cnn Accelerator For Energy Efficiency With An Extended Roofline Model, Sayed Omid Ayat, Mohamed Khalil-Hani, Ab Al-Hadi Ab Rahman

Turkish Journal of Electrical Engineering and Computer Sciences

In recent years, the convolutional neural network (CNN) has found wide acceptance in solving practical computer vision and image recognition problems. Also recently, due to its flexibility, faster development time, and energy efficiency, the field-programmable gate array (FPGA) has become an attractive solution to exploit the inherent parallelism in the feedforward process of the CNN. However, to meet the demands for high accuracy of today's practical recognition applications that typically have massive datasets, the sizes of CNNs have to be larger and deeper. Enlargement of the CNN aggravates the problem of off-chip memory bottleneck in the FPGA platform since there …

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Concurrency Control Algorithms For Deduplicated Cloud Storage, Prabavathy Balasundaram, Chitra Babu Jan 2018

Concurrency Control Algorithms For Deduplicated Cloud Storage, Prabavathy Balasundaram, Chitra Babu

Turkish Journal of Electrical Engineering and Computer Sciences

Deduplication of data is essential to effectively use cloud storage. As the metadata in deduplicated cloud storage are shared across multiple users, concurrent updates may result in inconsistencies. A coarse-grained locking strategy that has been proposed earlier to overcome this difficulty is not suited for inline deduplication owing to poor performance. In the present work, a fine-grained locking strategy that overcomes this shortcoming is proposed. A metadata structure along with a set of concurrent control mechanisms to accomplish this is presented. This strategy is shown to improve the throughput by as much as 60% with only marginal lock overhead.

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Analysis And Design Of A Converter Based On Noncascading Structure, Sunil Kumar, Kanwar Pal Singh Rana, Vineet Kumar Jan 2018

Analysis And Design Of A Converter Based On Noncascading Structure, Sunil Kumar, Kanwar Pal Singh Rana, Vineet Kumar

Turkish Journal of Electrical Engineering and Computer Sciences

In the present work, a converter employing two noncascading structures, combined in a single circuit, is presented. The power stored by the storage element is transferred to two subconverters by means of two storage capacitors that complement each other. The stress on the main power switch is of interest as it reduces as the load falls, which in turn reduces the power loss. By means of the storage elements, the input power factor as well as the load transient response can be improved simultaneously. The overall efficiency is high because the amount of power processed twice decreases. There is no …

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An Adaptive Fault Diagnosis Approach Using Pipeline Implementation For Railway Inspection, Yunus Santur, Mehmet Karaköse, Erhan Akin Jan 2018

An Adaptive Fault Diagnosis Approach Using Pipeline Implementation For Railway Inspection, Yunus Santur, Mehmet Karaköse, Erhan Akin

Turkish Journal of Electrical Engineering and Computer Sciences

Railway tracks must be periodically inspected. This study proposes a new approach for eliminating two major disadvantages experienced during rail inspection applications performed via computer vision. The first is the blurring effect on images, resulting from physical vibration during movement on the rail lines. This effect significantly reduces the high accuracy rate expected from anomaly inspection algorithms. The second disadvantage is the need to operate in real time. This study presents a new three-stage computer vision method approach that eliminates both disadvantages. First, a three-stage pipeline architecture is implemented and IMU-assisted blur detection is performed on images taken from the …

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High-Speed Switched Reluctance Machine: Natural Frequency Calculation And Acoustic Noise Prediction, Yusuf Yaşa, Yilmaz Sözer, Muhammet Gari̇p Jan 2018

High-Speed Switched Reluctance Machine: Natural Frequency Calculation And Acoustic Noise Prediction, Yusuf Yaşa, Yilmaz Sözer, Muhammet Gari̇p

Turkish Journal of Electrical Engineering and Computer Sciences

In this study, an analytical model is proposed for natural frequency calculation and acoustic noise prediction for high speed switched reluctance machines. The developed natural frequency model results are compared with the mechanical finite element analysis results in terms of 6 different mode shapes that cause the majority of the acoustic noise in switched reluctance machines. The results show that the analytical results are consistent with the numerical method results with minimum 90% matching. Based on the natural frequency calculation model, a new acoustic noise prediction method is developed that only needs a radial force waveform as an input emerging …

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Simplification Of Harmonics Filter For A Matrix Converter-Based Drive, Gytis Petrauskas, Gytis Svinkunas, Rasa Juraskiene Jan 2018

Simplification Of Harmonics Filter For A Matrix Converter-Based Drive, Gytis Petrauskas, Gytis Svinkunas, Rasa Juraskiene

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, an analysis of the interaction between the switching ripple filter components of a matrix converter-based drive and the components of a 0.4-kV electrical grid is presented. Based on the analysis, we propose a simplification of the conventional LCR filter. An inductance of the power grid transformer windings and an impedance of the power distribution lines could be considered as a filter component. Stemming from the above, a simplification of the filter topology is proposed. Only the capacitance component is necessary for realizing a conventional LCR filter. The effectiveness of this simplification is demonstrated through calculations, simulations performed …

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Design And Comparison Of Embedded Air Coils For Small Satellites, Anwar Ali, Zeeshan Mukhtar, Khalil Ullah, Leonardo Reyneri Jan 2018

Design And Comparison Of Embedded Air Coils For Small Satellites, Anwar Ali, Zeeshan Mukhtar, Khalil Ullah, Leonardo Reyneri

Turkish Journal of Electrical Engineering and Computer Sciences

The paper discusses the comparison of different shapes of embedded air coils for the attitude control of small satellites. Various systems are available in the market for the attitude control of small satellites such as reaction wheels, permanent magnets, magnetic rods, and thrusters. The available systems have large size, heavier weight, and relatively higher power consumption. A miniaturized system with less power consumption and heat dissipation is required that can provide the anticipated torque. This paper focuses on the design and comparison of square and circular air coils embedded in four internal layers (i.e. 2nd, 3rd, 4th, and 5th) of …

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Electronically Tunable Grounded/Floating Inductance Simulators Using Z-Copy Cfccc, Alok Kumar Singh, Pragati Kumar, Raj Senani Jan 2018

Electronically Tunable Grounded/Floating Inductance Simulators Using Z-Copy Cfccc, Alok Kumar Singh, Pragati Kumar, Raj Senani

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, new electronically tunable grounded and floating inductance simulators employing a Z-copy current follower current controlled conveyor (CFCCC) and one grounded capacitor have been proposed and their workability has been demonstrated by PSPICE simulations in 0.18-$\mu $m TSMC CMOS technology.

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Unit Commitment Considering The Emergency Demand Response Programs And Interruptible/Curtailable Loads, Javad Nikoukar Jan 2018

Unit Commitment Considering The Emergency Demand Response Programs And Interruptible/Curtailable Loads, Javad Nikoukar

Turkish Journal of Electrical Engineering and Computer Sciences

After restructuring the power systems, demand response programs form the main part of consumption management programs. This is because these programs are by nature particularly suitable for adapting to the new structure in power system management. These programs are considered as a suitable solution for solving some problems in power system restructuring. Unit commitment (UC) programs are used for power production with minimum cost. In this paper, after presenting an overview of demand response methods, a mechanism is proposed for simultaneous execution of the UC program, emergency demand response programs, and interruptible/curtailable loads. The proposed mechanism, in addition to decreasing …

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Measurement Of Active Power, Electrical Energy, And Trms Voltage And Current Using The Dual Slope Conversion Technique, Khaoula Khlifi, Ahlem Ayari, Amira Haddouk, Hfaiedh Mechergui Jan 2018

Measurement Of Active Power, Electrical Energy, And Trms Voltage And Current Using The Dual Slope Conversion Technique, Khaoula Khlifi, Ahlem Ayari, Amira Haddouk, Hfaiedh Mechergui

Turkish Journal of Electrical Engineering and Computer Sciences

We have exploited the dual slope (DS) conversion technique to realize an intelligent system with high resolution that ensures active power measurement and electrical energy consumption. The load power is suited by two Hall effect current and voltage transducers, which are associated upstream with a precision analogue multiplier. A DS analogue-to-digital converter (DS-ADC) performs the conversion by rejecting noise with a conversion time that is multiple frequencies of the ADC's first slope. The digital acquisition is made by a PIC 16F877 using a management algorithm ensuring the control, acquisition, and treatment of information. Results are displayed on a 2-line and …

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Electrostatic Discharge Currents And Their Derivatives' Approximation By Piecewise Power-Exponential Functions, Vesna Javor, Karl Lundengard, Milica Rancic, Sergei Silvestrov Jan 2018

Electrostatic Discharge Currents And Their Derivatives' Approximation By Piecewise Power-Exponential Functions, Vesna Javor, Karl Lundengard, Milica Rancic, Sergei Silvestrov

Turkish Journal of Electrical Engineering and Computer Sciences

An analytically extended function based on power-exponential functions is used in this paper for approximation of electrostatic discharge (ESD) currents and their derivatives. The Marquardt least-squares method (MLSM) is applied for obtaining nonlinear function parameters. IEC 61000-4-2 Standard ESD current is approximated, as well as some measured ESD currents' wave shapes. Power-exponential terms are extended at the local maxima and minima of the represented wave shape, so that this approximation is done from peak to peak. ESD current derivative is approximated using the same procedure in order to obtain the continuous second order derivative of the current, as all piecewise …

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Optimal Sizing Hydrokinetic-Photovoltaic System For Electricity Generation In A Protected Wildlife Area Of Ecuador, Juan Lata- Garcia, Francisco Jurado-Melguizo, Higinio Sanchez-Sainz, Christopher Reyes-Lopez, Luis Fernandez- Ramirez Jan 2018

Optimal Sizing Hydrokinetic-Photovoltaic System For Electricity Generation In A Protected Wildlife Area Of Ecuador, Juan Lata- Garcia, Francisco Jurado-Melguizo, Higinio Sanchez-Sainz, Christopher Reyes-Lopez, Luis Fernandez- Ramirez

Turkish Journal of Electrical Engineering and Computer Sciences

Rural electrification is one of the most significant issues faced by electricity companies. For this reason, these companies are choosing alternative sources to generate energy in isolated regions. Furthermore, hybrid generation systems are an effective option for supplying protected areas. In this context, this research aims at designing an autonomous hybrid system to meet the annual electricity demand of the inhabitants of a national park. Fluvial and solar energies are the best options to reduce environmental impact and to ensure the conservation of the endemic fauna and flora of the island at a low carbon footprint. The system comprises a …

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Energy Efficiency With An Application Container, Özmen Emre Demi̇rkol, Aşkin Demi̇rkol Jan 2018

Energy Efficiency With An Application Container, Özmen Emre Demi̇rkol, Aşkin Demi̇rkol

Turkish Journal of Electrical Engineering and Computer Sciences

Efficient use of energy is an issue that the information technology (IT) world gives prominence to both in academia and industry. Cloud computing and the Internet of things, today's most popular subjects, make the efficient use of resources and energy even more important. Every year, millions of smart devices connected to the Internet increase the demand for data center capacity to provide service to those devices. This increases energy consumption in the IT sector. Thus, more efficient use of energy in these systems is of critical importance. The increase in the migration to cloud computing makes fast and efficient infrastructure-as-a-service …

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A Compact Branch-Line Coupler Design Using Low-Pass Resonators And Meandered Lines Open Stubs, Fatemeh Hosseinkhani, Saeed Roshani Jan 2018

A Compact Branch-Line Coupler Design Using Low-Pass Resonators And Meandered Lines Open Stubs, Fatemeh Hosseinkhani, Saeed Roshani

Turkish Journal of Electrical Engineering and Computer Sciences

A compact 1.5 GHz microstrip branch-line coupler with harmonic suppression, using low-pass resonators and meandered lines open stubs, is designed and fabricated in this paper. Both significant size reduction and harmonics suppression are achieved in the proposed structure using U-shape low-pass resonators and meandered lines open stubs. The proposed coupler shows more than 24 dB suppression for harmonics (2nd up to 10th). The proposed coupler size has been reduced by almost up to 81{\%} compared to the typical one. The designed coupler is simulated using Advanced Design System software. The measured results verify the simulation data of the designed coupler.

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A Comparative Study On Different Types Of Metamaterials For Enhancement Of Microstrip Patch Antenna Directivity At The Ku-Band (12 Ghz), Bi̇lal Tütüncü, Hami̇d Torpi̇, Bülent Urul Jan 2018

A Comparative Study On Different Types Of Metamaterials For Enhancement Of Microstrip Patch Antenna Directivity At The Ku-Band (12 Ghz), Bi̇lal Tütüncü, Hami̇d Torpi̇, Bülent Urul

Turkish Journal of Electrical Engineering and Computer Sciences

This paper proposes improving the directivity of microstrip patch antennas (MPAs) by using metamaterials. Four different metamaterial types are used as a flat lens in front of the MPA, respectively, which are tuned to 12 GHz (Ku-band) resonance frequency. Thus, it can be decided which metamaterial is more proper for antenna directivity enhancement at this band. One additional new metamaterial structure is proposed in this paper, which is called a Euro-shaped resonator, and other metamaterials used are the triangular split ring resonator, symmetrical ring structure, and split ring resonator. The permeability and permittivity of metamaterials are extracted from the S …

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A New Inset-Fed Uwb Printed Antenna With Triple 3.5/5.5/7.5-Ghz Band-Notched Characteristics, Avez Syed, Rabah Wasel Aldhaheri Jan 2018

A New Inset-Fed Uwb Printed Antenna With Triple 3.5/5.5/7.5-Ghz Band-Notched Characteristics, Avez Syed, Rabah Wasel Aldhaheri

Turkish Journal of Electrical Engineering and Computer Sciences

A novel low-profile inset-fed ultrawideband printed antenna with triple band-notched characteristics is proposed. Wide inverted U-shaped and crescent-shaped slots are used to achieve first and second notched bands in the 3.3--3.7 GHz and 5.1--5.9 GHz ranges for WiMAX and WLAN systems, respectively. Additionally, an altered ground plane with an open-ended L-shaped slot generated a third notched band in the 7.25--7.85 GHz range for downlink of X-band satellite communication systems. The center frequencies of the stop bands are adjusted by altering the parameters of corresponding slots. The antenna prototype is built on a 28 mm $\times $ 24 mm Rogers RT/duroid …

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Investigating The Experimental Limits Of The Brewster's Angle Method, Can Sümer, Alp Kuştepeli̇, Mehmet Sali̇h Di̇nleyi̇ci̇ Jan 2018

Investigating The Experimental Limits Of The Brewster's Angle Method, Can Sümer, Alp Kuştepeli̇, Mehmet Sali̇h Di̇nleyi̇ci̇

Turkish Journal of Electrical Engineering and Computer Sciences

We present the method, analysis, and experimental results of the Brewster's angle method commonly used for determining the refractive indices of optical films. We show the significance of the intersection of reflectance curves, in that the necessity for substrate refractive index and film layer thickness knowledge are both eliminated. We present the conditions for the existence of the second intersection of reflectance curves and introduce a method for determining the refractive index of the substrate layer by using the angular information alone. Analytical results reveal impressive practical sensitivity and accuracy limits for the method, where the experimental results also support …

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