Turgut Ozturk

Extracting the dielectric constant of materials using ABC-based ANNs and NRW algorithms

ABSTRACT Five different Nicolson–Ross–Weir (NRW) extracting techniques are used to extract the dielectric constants of Teflon, Rexolite, Glass (borosilicate and soda-lime), Paper, and Ultralam 3850HT from S-parameters. The results of these extraction techniques are used to train the Artificial Neural Networks. In order to improve the accuracy of the results, the weights of ANNs are calculated using artificial bee colony estimation method. The results are compared with that obtained using NRW, Newton–Raphson, and genetic algorithm. The obtained results indicate that the proposed model gives good extracted parameters as compared with the previously published results.

Materials classification by partial least squares using S-parameters

This paper presents a simple and usable algorithm, which is called Partial Least Squares, to classify the samples in different thicknesses and frequency range. This model employed to reconstruct the samples using S-parameters which are collected by Vector Network Analyzer in Free Space Measurement method. The relationship of between S-parameters is showed to classify the materials using proposed model. The Partial Least Squares algorithm has a good potential to classify the different samples with non-contactless and non-destructive measurement method. The classification process will be easy by using the proposed model, due to its practical and simple usage. In addition, the extraction techniques, which are Nicolson Ross Weir, Newton–Raphson, and Genetic Algorithm, are used in order to extract the dielectric constant of samples, in this study. The Newton–Raphson algorithm is selected to obtain the complex permittivity of samples since it gives best results than other extracting techniques and the results are used for classification.

Improving the Energy Management of a Solar Electric Vehicle

A solar electric vehicle (SEV) is an electric vehicle (EV) with onboard photovoltaic cells charging a set of batteries for extended driving range. This study aimed to improve the energ ...

An induction motor design for urban use electric vehicle

Because of fossil fuel shortage and its damages on environment, electric vehicles (EV) are going to be more popular in science and car industry as well. So, EVs take an opportunity to spread over the traffic finally. But battery, which is the main energy supplier of the motor, has disadvantages as big volume and weight. Scientists try to enhance energy densities, ranges and quicken charging. All of research results force us to drive EV in a loop, close to charging stations for near future. So EVs should be designed by considering urban road and speed conditions as well. In this survey, we designed a new two pole 7,5 kW induction motor for a certain electric vehicle, which was designed to use urban drive. We considered urban traffic rules and conditions, while designing the motor. We simulated and verified analytical and finite element analysis of the designed induction motor. We also modelled and simulated the EV with the induction motor on MATLAB to observe control performance of field oriented control (FOC) on several urban use scenarios. According to our results, EV with designed motor can be realized and controlled.

Reduction of S-parameter errors using singular spectrum analysis

A free space measurement method, which consists of two horn antennas, a network analyzer, two frequency extenders, and a sample holder, is used to measure transmission (S21) coefficients in 75-110 GHz (W-Band) frequency range. Singular spectrum analysis method is presented to eliminate the error and noise of raw S21 data after calibration and measurement processes. The proposed model can be applied easily to remove the repeated calibration process for each sample measurement. Hence, smooth, reliable, and accurate data are obtained to determine the dielectric properties of materials. In addition, the dielectric constant of materials (paper, polyvinylchloride-PVC, Ultralam® 3850HT, and glass) is calculated by thin sheet approximation and Newton-Raphson extracting techniques using a filtered S21 transmission parameter.

A Single Band Antenna Design for Future Millimeter Wave Wireless Communication at 38 GHz

In this proposed paper, a single band microstrip patch antenna for fifth generation (5G) wireless application was presented. 28, 38, 60 and 73 GHz frequency bands have been allocated for 5G mobile communications by International Telecommunications Union (ITU). In this paper, we proposed an antenna, which is suitable for the millimeter wave frequency. The single band antenna consists of new slot loaded on the radiating patch with the 50 ohms microstrip line feeding used. This single band antenna was simulated on a FR4 dielectric substrate have relative permittivity 4.4, loss tangent 0.02, and height 1.6 mm. The antenna was simulated by Electromagnetic simulation, computer software technology High Frequency Structural Simulator. And simulated result on return loss, VSWR, radiation pattern and 3D gain was presented. The parameters of the results well coherent and proved the literature for millimeter wave 5G wireless application at 38 GHz.

Experimental studies based on classification of explosive and non-explosive liquids

Nowadays, since the explosive liquids can easily be obtained by mixing simple substances, the electromagnetic methods developed for safety purposes have gained acceleration. In this study; liquids which may be explosive with chemical explosion, combustion and combination, as well as, non-explosive liquids which may be found inside baggages in airports are used to measure electromagnetic responses ranging from 1–50 GHz and complex dielectric permeability coefficients are calculated with commercial software. Explosive and non-explosive liquids are classified a with the help of three different algorithms such as PLS, PCA and K-Means.

Permittivity measurements for dielectric lens and dielectric rod antenna designs

For dielectric materials being often utilized in quasi-optical components, the permittivity was evaluated by free-space method in W-band. The obtained permittivity value was applied to designing of low aberration large aperture aspheric dielectric lens and dielectric waveguide rod antenna. These components composed the antenna system for the passive radiometric imaging in 90-100 GHz frequency range. This antenna system was experimentally demonstrated to successfully detect and recognize the metallic weapon hidden under outer clothing.

Research on Control Strategy and Energy Consumption for Electric Vehicles

This paper presents the effect of different control methods on energy consumption of the electric vehicle. The vehicle model was created with Matlab program that has three components; battery model, IM driver model and drivetrain model, respectively. The commonly used drive cycle ECE-15 is adopted for simulation. PI and Fuzzy Logic control methods were applied on electric vehicle and the energy consumption of battery were compared by two different control methods for electric vehicle. Analysis of energy consumption has been intended by selecting the values of 50 km/h, 90 km/h and 120 km/h as reference velocities. Simulations like this will help which FLC method is more useful for performance of electric vehicle.