Sukru Ozen - Academia.edu (original) (raw)

Papers by Sukru Ozen

2021 Photonics & Electromagnetics Research Symposium (PIERS), 2021

Acoustic waves are longitudinal waves and create sound pressure due to particle velocity and vibr... more Acoustic waves are longitudinal waves and create sound pressure due to particle velocity and vibration direction. The FDTD method is increasingly used in acoustic simulations. In the study, the alterations of pressure and velocity caused by sound waves on different media surfaces were discussed. Sound waves were used in the study due to their similarity to ultrasound waves. The Gaussian pulse wave model was considered as the wave model. Inanimate surfaces such as air, water, glass, and polyethylene were analyzed as media surfaces, and brain and breast tissue surfaces were selected as different tissue types. Finite difference time domain (FDTD) method was used in the analysis of acoustic waves. The analyses of the sampled Gaussian sound wave signify that as the number of iterations increased, the propagation value increased correspondingly. The pressure (Pmathrmbreastmax=0.99mathrmP˜a,Pmathrmbrainmax=0.97mathrmP˜a)(P_{\mathrm{breast}}^{\max}=0.99\mathrm{~Pa},P_{\mathrm{brain}}^{\max}=0.97\mathrm{~Pa})(Pmathrmbreastmax=0.99mathrmP˜a,Pmathrmbrainmax=0.97mathrmP˜a) and velocity left(Vtextbreastmax=right.left.0.65mumathrmm/mathrmsn,Vtextbrainmax=0.64mumathrmm/mathrmsnright)\left(V_{\text {breast }}^{\max }=\right. \left.0.65 \mu \mathrm{m} / \mathrm{sn}, V_{\text {brain }}^{\max }=0.64 \mu \mathrm{m} / \mathrm{sn}\right)left(Vtextbreastmax=right.left.0.65mumathrmm/mathrmsn,Vtextbrainmax=0.64mumathrmm/mathrmsnright) of the sound wave show so close characteristics in both breast and brain tissues.

Shielding efiectiveness (SE) of multi-layered shield models of two and three layered structures a... more Shielding efiectiveness (SE) of multi-layered shield models of two and three layered structures are investigated. For high frequency analysis, SE declines are noted.

Electromagnetic Biology and Medicine, 2021

ABSTRACT With the development of today’s technology, the electromagnetic radiation spread by mobi... more ABSTRACT With the development of today’s technology, the electromagnetic radiation spread by mobile phones and base stations is also rapidly increasing, and this causes serious concerns about the environment and human health. The Drosophila model organism is widely used in genetic toxicology studies because its genome is highly similar to the genes identified in human diseases. In this study, the genotoxic effects of radiofrequency electromagnetic radiation were evaluated by the wing Somatic Mutation and Recombination Test (SMART) in Drosophila melanogaster at 900 MHz, 1800 MHz, and 2100 MHz. The SMART method is based on the observation of genetic changes occurring in the trichomes of the Drosophila wings appearing as mutant clones under the microscope. Throughout the study, total clone parameters were evaluated by exposing the Drosophila larvae to electromagnetic fields for two, four, and six hours per day for two days. As a result of the study, it was observed that the number of mutant clones was statistically increased according to the negative control group in all applications except for the six-hour application at 1800 MHz.

2010 15th National Biomedical Engineering Meeting, 2010

... Evaluation of the Electric and Magnetic Field Levels of Around the Medium Voltage Power Lines... more ... Evaluation of the Electric and Magnetic Field Levels of Around the Medium Voltage Power Lines in Related to Public Health Evin Gizem ÖGEL, şükrü ÖZEN ve Selçuk HELHEL ... Leukemia and residence near electrical transmission lines: a case control study. Br J Cancer. ...

2021 Photonics & Electromagnetics Research Symposium (PIERS)

Lightning electromagnetic impulse (LEMP) falling on a power line or power plant creates an effect... more Lightning electromagnetic impulse (LEMP) falling on a power line or power plant creates an effect like closing a large switch between a large current source and a power line circuit. Turning off this switch generates a transient state by causing a sudden change in circuit conditions. In order to minimize the damage caused by this situation on the lines, protection elements are used. If a LEMP impact falls on a power plant or power transmission line, the most effective way to protect against them is the use of surge arresters. They ensure that these peak currents are drawn to the ground thanks to their non-linear resistance structures and are generally used at the entrance of transformer centers. However, in recent years, besides being used at the end of the line or at the beginning of the line, it has also started to be used by inserting to certain line poles. This has led to the rapid development of polymeric ZnO surge arresters. Recently, a significant number of line surge arresters with different voltage levels are in service. In the study, the situation created by the line surge arresters against the fault due to the LEMP hitting the protection conductor on the energy transmission line axis was examined. By using the ATP-EMTP software, the contribution of line surge arresters to protect a realistic 380 kV double-circuit overhead transmission line from LEMP has been investigated. All the models were compared with the existing models in the literature, and practical suggestions were made for the improvement of energy transmission lines against LEMP failures.

2019 Medical Technologies Congress (TIPTEKNO)

In this study, especially the effects of wireless communication systems used in industrial areas ... more In this study, especially the effects of wireless communication systems used in industrial areas on human body with implant were investigated. The specific absorption rate (SAR) changes on a model considering the electrical properties of the human body in the study were determined in the tissue of interest. Nowadays, radio frequency waves are increasingly exposed in parallel with the rapid spread of the use of these devices. There are many studies reporting that harmful effects of this uncontrolled exposure on living organisms are present. In this study, a plane wave source was placed near the human model. Average SAR mass was taken as 10 grams. In the simulations, the electric field values for the 900 MHz, 1800 MHz and 2450 MHz operating frequencies were taken as 41.25 V/m, 58.33 V/m and 61 V/m respectively (the radiation limits set by ICNIRP for public exposure). According to the obtained simulation results, it was observed that the SAR values were increased in the arm with implant at the 1800 and 2450 MHz frequencies compared to the non-implanted model, and it was also observed that as the frequency value decreased.

2019 Medical Technologies Congress (TIPTEKNO)

Behavior of the electromagnetic field acting on any tissue can be explained by electromagnetic do... more Behavior of the electromagnetic field acting on any tissue can be explained by electromagnetic dosimetry. As a result of unexpected exposure of external electromagnetic fields to biological tissue, adverse effects are observed. In this study, electromagnetic dosimetry evaluation of rats has been performed with finite integration technique (FIT) based specific absorption rate (SAR) simulations. A monopole antenna radiating at 2100 MHz has been designed as external electromagnetic source. The antenna has been located at 4 cm and 14 cm away from the nearest point of the rat model and whole body total SAR for model has been calculated as 0.22 W/kg and 0.039 W/kg, respectively. Induced SAR at the head and body models have been varied due to the electrical properties of each tissue. Also, as the distance between the antenna and the rat model has increased, the induced SAR has decreased. Results showed that the 1 gr average tissue SAR results was higher than the 10 gr average tissue SAR results.

2019 Medical Technologies Congress (TIPTEKNO), 2019

In this study, galvanic coupled intrabody communication has been studied due to finite element me... more In this study, galvanic coupled intrabody communication has been studied due to finite element method. Thus, electric field distribution and induced current densities have been analyzed. Multi-layered cylinder has been examined as the tissue model and modelled as skin, fat, muscle, cortical bone, cancellous bone. During the investigations, both physical and electrical properties of the tissues have been considered according to realistic values. Simulations have been performed at 1 MHz, 10 MHz and 21 MHz. Results showed that the electrical properties of the tissues have different variations at the operating frequencies, and as a result of this, it has been shown that the behavior of the signal in the tissue has changed. Electric field distributions have been obtained mostly in tissue layers close to the electrodes for all three frequencies. Maximum current density has been induced in muscle tissue for 1 MHz, whereas it has been observed in skin tissue for 10 MHz and 21 MHz.

There is a tremendous increase in use of RF electronics in veterinary for tracking and health che... more There is a tremendous increase in use of RF electronics in veterinary for tracking and health check of animals. The mechanisms of magnetic and electromagnetic effects in biological systems are known, effect of electromagnetics in biological tissues are generally studied in human tissues in the literature, and the mechanism was convincingly established for enzymatic adenosine triphosphate (ATP) and desoxynucleic acid (DNA) synthesis. In this study, the SAR effect of pH boluses used to monitor the rumen pH value of animals has been tried to be revealed. For this purpose, active RFID tags operating at 434 MHz have been placed in the rumen zone by adding a pH sensor and the rumen pH values have been monitored dynamically for two months. The SAR value generated by active RFID tag antennas with 1 mW output power has been modeled with the help of a simulation program. The resulting SAR effect appears to be well below the legal limit. Keywords— SAR, Active RFID Tags, pH bolus.

Scientific Research and Essays, 2013

The polynomial-based differential quadrature method (PDQM) and Fourier expansion-based differenti... more The polynomial-based differential quadrature method (PDQM) and Fourier expansion-based differential quadrature method (FDQM) are examined to solve 2D Helmholtz problem expressing definition of many electromagnetic problems. PDQM and FDQM solution of the problems were calculated and compared, analytically. While grid node and wave number are steady, the PDQM and FDQM were applied to 2D Helmholtz problem for calculation and comparison. While the grid node is equal to 7 (N=M=7) and the wave number is equal to 1 (k=1), (maximum absolute error between the numerical result and the exact solution) for PDQM and for FDQM has been found as 2.758×10-5 and 2.921×10-6 respectively. Then wave number was increased in order to examine the effects of its variation to the accuracy, while grid node was kept in steady state. While grid node was steady and equal to 7 and the wave number was increased from 1 to 5, for FDQM has been found as 2.921×10-6, 7.995×10-5, 1.020×10-4, 0.1825 and 1.779 respectiv...

In this study, planar near-fleld antenna measurement system has been used as a controlled radar s... more In this study, planar near-fleld antenna measurement system has been used as a controlled radar setup and bistatic wave scattering conditions have been formed. A metal having 1cm £ 5cm dimensions has been buried in a non-conductive cylinder having a diameter of 5cm and height of 10cm. Then, electromagnetic scattering pattern of cylinder has been obtained by using S21 parameter. Using some image processing techniques on obtained pattern, detection of the metal buried in cylinder has been realized. The detection of buried objects in other mediums is important since there are many related appli- cations such as security, military, and medical applications. This issue force scientists to conduct researches on similar issues (1{3). Marr etal. (1) investigated the scattering characteristic of the metallic sphere by using cylindrical near fleld scanning system. They investigated the radar cross section and pattern of the sphere by putting it in the center of the scanner They compared numerical solutions with far fleld data computed from measured near fleld. Amineh etal. (2) investigated the capabilities and limits of the horn antennas flrst and then they proposed a microwave imaging setup by using planar aperture raster scanning. They used blind de-convolution algorithm and tested the performance of their technique. Burkholder etal. (3) used model-based imaging method instead of conventional imaging ap- proaches and they investigated the detection of objects inside a room. Since the topic has many applications, it is important to develop an e-cient technique. In this study, buried metal detection has been realized by using a planar near fleld antenna measurement system, which is mainly used for measuring and testing antennas, as a bistatic radar setup. Also, image processing techniques have been used.

Radiation Protection Dosimetry, 2021

In this study, electric field and magnetic field strengths at 50 Hz are measured in a solar power... more In this study, electric field and magnetic field strengths at 50 Hz are measured in a solar power plant located far from residential areas, and the measurement results near various sources of the electric and magnetic fields in the power plant are presented. Although the measured values for the electric field caused by the solar panel range between 0.07 and 1.33 V/m, the measured values for the magnetic field by the solar panel range between 0.037 and 0.19 μT. In front of the inverter, the measured value of the electric field reaches 0.7 V/m, whereas the measured value of the magnetic field reaches 2.2 μT. The results are presented and evaluated in light of the exposure limits to electromagnetic fields published by international organisations.

International Journal Of Engineering & Applied Sciences, 2015

International Journal Of Engineering & Applied Sciences, 2015

International Journal of Occupational Safety and Ergonomics, 2021

Non-ionising dosimetry investigations of extremely low frequency (ELF) magnetic fields that are g... more Non-ionising dosimetry investigations of extremely low frequency (ELF) magnetic fields that are generated by underground power cables as well as the minimisation of their health effects are significant topics handled by numerous researchers. In this study, ELF magnetic fields and current densities caused by three-phased underground transmission lines induced in the human model were examined utilising both analytical and numerical methods. Analyses were carried out using a two-dimensional problem scenario for the comprehensive head and body model. The results of the finite element method-based (FEM) simulation studies and the analytical calculations are consistent with each other. Moreover, a magnetic field shielding method utilising conductive material was presented in the study. The shielding technique performed with copper material was carried out to mitigate the magnetic field and possible dosimetry hazards in the ELF region. The proposed shield was a four millimetre (mm) reversed-U-shaped copper material.

Nowadays, complex electromagnetic scenarios carried out by numerical techniques can be solved eas... more Nowadays, complex electromagnetic scenarios carried out by numerical techniques can be solved easily by state-of-the-art technology computers. Thus, many numerical techniques have been emerged in order to solve the different problems. In this way, scientists can define and predict the various circumstances for any problem. In this study, a microstrip patch antenna has been analyzed by using finite difference time domain (FDTD) method which is the one of the most utilized technique in computational electromagnetics. Antenna has been fed through the Gaussian pulse from the microstrip line. Microstrip patch antenna has been designed as three layered structure which are ground, substrate and patch. Although the ground and patch layers have been selected as perfectly electric conductor (PEC), substrate layer has been selected as a dielectric material whose dielectric constant has been 4.4. Also, designed antenna has been surrounded by perfectly matched layer (PML). FDTD based investigati...

IEEE Antennas and Wireless Propagation Letters, 2008

Mühendislik Bilimleri ve Tasarım Dergisi, 2020

2017 Progress In Electromagnetics Research Symposium - Spring (PIERS)

The characteristic parameters of the lightning electromagnetic pulse (LEMP) current have been inv... more The characteristic parameters of the lightning electromagnetic pulse (LEMP) current have been investigated for many years on the basis of the isolation coordination by scientists studying in the field of electricity and physics. The necessity of studying in this area has arisen in order to protect the electrical and electronic equipment inside the power transmission lines and electrical installations against the harmful effects of the harmonic current of the lightning electromagnetic pulse. In this study, the over-voltages, which occur due to the lightning electromagnetic wave strikes on the pylons, were investigated with the Alternative Transient Program (ATP). The Heidler function is used to simulate the LEMP model. Analyzes of the over-voltages that occur as a result of the lightning strike to the protection conductor on the top of a grounded pole or one of the pole conductors of the pylon are carried out. Moreover, high voltage, electric field and magnetic field changes in the environment where the lightning electromagnetic pulse strikes are analyzed numerically in MATLAB using Rusk equations and compared with ATP simulation results.

2021 Photonics & Electromagnetics Research Symposium (PIERS), 2021

Acoustic waves are longitudinal waves and create sound pressure due to particle velocity and vibr... more Acoustic waves are longitudinal waves and create sound pressure due to particle velocity and vibration direction. The FDTD method is increasingly used in acoustic simulations. In the study, the alterations of pressure and velocity caused by sound waves on different media surfaces were discussed. Sound waves were used in the study due to their similarity to ultrasound waves. The Gaussian pulse wave model was considered as the wave model. Inanimate surfaces such as air, water, glass, and polyethylene were analyzed as media surfaces, and brain and breast tissue surfaces were selected as different tissue types. Finite difference time domain (FDTD) method was used in the analysis of acoustic waves. The analyses of the sampled Gaussian sound wave signify that as the number of iterations increased, the propagation value increased correspondingly. The pressure (Pmathrmbreastmax=0.99mathrmP˜a,Pmathrmbrainmax=0.97mathrmP˜a)(P_{\mathrm{breast}}^{\max}=0.99\mathrm{~Pa},P_{\mathrm{brain}}^{\max}=0.97\mathrm{~Pa})(Pmathrmbreastmax=0.99mathrmP˜a,Pmathrmbrainmax=0.97mathrmP˜a) and velocity left(Vtextbreastmax=right.left.0.65mumathrmm/mathrmsn,Vtextbrainmax=0.64mumathrmm/mathrmsnright)\left(V_{\text {breast }}^{\max }=\right. \left.0.65 \mu \mathrm{m} / \mathrm{sn}, V_{\text {brain }}^{\max }=0.64 \mu \mathrm{m} / \mathrm{sn}\right)left(Vtextbreastmax=right.left.0.65mumathrmm/mathrmsn,Vtextbrainmax=0.64mumathrmm/mathrmsnright) of the sound wave show so close characteristics in both breast and brain tissues.

Shielding efiectiveness (SE) of multi-layered shield models of two and three layered structures a... more Shielding efiectiveness (SE) of multi-layered shield models of two and three layered structures are investigated. For high frequency analysis, SE declines are noted.

Electromagnetic Biology and Medicine, 2021

ABSTRACT With the development of today’s technology, the electromagnetic radiation spread by mobi... more ABSTRACT With the development of today’s technology, the electromagnetic radiation spread by mobile phones and base stations is also rapidly increasing, and this causes serious concerns about the environment and human health. The Drosophila model organism is widely used in genetic toxicology studies because its genome is highly similar to the genes identified in human diseases. In this study, the genotoxic effects of radiofrequency electromagnetic radiation were evaluated by the wing Somatic Mutation and Recombination Test (SMART) in Drosophila melanogaster at 900 MHz, 1800 MHz, and 2100 MHz. The SMART method is based on the observation of genetic changes occurring in the trichomes of the Drosophila wings appearing as mutant clones under the microscope. Throughout the study, total clone parameters were evaluated by exposing the Drosophila larvae to electromagnetic fields for two, four, and six hours per day for two days. As a result of the study, it was observed that the number of mutant clones was statistically increased according to the negative control group in all applications except for the six-hour application at 1800 MHz.

2010 15th National Biomedical Engineering Meeting, 2010

... Evaluation of the Electric and Magnetic Field Levels of Around the Medium Voltage Power Lines... more ... Evaluation of the Electric and Magnetic Field Levels of Around the Medium Voltage Power Lines in Related to Public Health Evin Gizem ÖGEL, şükrü ÖZEN ve Selçuk HELHEL ... Leukemia and residence near electrical transmission lines: a case control study. Br J Cancer. ...

2021 Photonics & Electromagnetics Research Symposium (PIERS)

Lightning electromagnetic impulse (LEMP) falling on a power line or power plant creates an effect... more Lightning electromagnetic impulse (LEMP) falling on a power line or power plant creates an effect like closing a large switch between a large current source and a power line circuit. Turning off this switch generates a transient state by causing a sudden change in circuit conditions. In order to minimize the damage caused by this situation on the lines, protection elements are used. If a LEMP impact falls on a power plant or power transmission line, the most effective way to protect against them is the use of surge arresters. They ensure that these peak currents are drawn to the ground thanks to their non-linear resistance structures and are generally used at the entrance of transformer centers. However, in recent years, besides being used at the end of the line or at the beginning of the line, it has also started to be used by inserting to certain line poles. This has led to the rapid development of polymeric ZnO surge arresters. Recently, a significant number of line surge arresters with different voltage levels are in service. In the study, the situation created by the line surge arresters against the fault due to the LEMP hitting the protection conductor on the energy transmission line axis was examined. By using the ATP-EMTP software, the contribution of line surge arresters to protect a realistic 380 kV double-circuit overhead transmission line from LEMP has been investigated. All the models were compared with the existing models in the literature, and practical suggestions were made for the improvement of energy transmission lines against LEMP failures.

2019 Medical Technologies Congress (TIPTEKNO)

In this study, especially the effects of wireless communication systems used in industrial areas ... more In this study, especially the effects of wireless communication systems used in industrial areas on human body with implant were investigated. The specific absorption rate (SAR) changes on a model considering the electrical properties of the human body in the study were determined in the tissue of interest. Nowadays, radio frequency waves are increasingly exposed in parallel with the rapid spread of the use of these devices. There are many studies reporting that harmful effects of this uncontrolled exposure on living organisms are present. In this study, a plane wave source was placed near the human model. Average SAR mass was taken as 10 grams. In the simulations, the electric field values for the 900 MHz, 1800 MHz and 2450 MHz operating frequencies were taken as 41.25 V/m, 58.33 V/m and 61 V/m respectively (the radiation limits set by ICNIRP for public exposure). According to the obtained simulation results, it was observed that the SAR values were increased in the arm with implant at the 1800 and 2450 MHz frequencies compared to the non-implanted model, and it was also observed that as the frequency value decreased.

2019 Medical Technologies Congress (TIPTEKNO)

Behavior of the electromagnetic field acting on any tissue can be explained by electromagnetic do... more Behavior of the electromagnetic field acting on any tissue can be explained by electromagnetic dosimetry. As a result of unexpected exposure of external electromagnetic fields to biological tissue, adverse effects are observed. In this study, electromagnetic dosimetry evaluation of rats has been performed with finite integration technique (FIT) based specific absorption rate (SAR) simulations. A monopole antenna radiating at 2100 MHz has been designed as external electromagnetic source. The antenna has been located at 4 cm and 14 cm away from the nearest point of the rat model and whole body total SAR for model has been calculated as 0.22 W/kg and 0.039 W/kg, respectively. Induced SAR at the head and body models have been varied due to the electrical properties of each tissue. Also, as the distance between the antenna and the rat model has increased, the induced SAR has decreased. Results showed that the 1 gr average tissue SAR results was higher than the 10 gr average tissue SAR results.

2019 Medical Technologies Congress (TIPTEKNO), 2019

In this study, galvanic coupled intrabody communication has been studied due to finite element me... more In this study, galvanic coupled intrabody communication has been studied due to finite element method. Thus, electric field distribution and induced current densities have been analyzed. Multi-layered cylinder has been examined as the tissue model and modelled as skin, fat, muscle, cortical bone, cancellous bone. During the investigations, both physical and electrical properties of the tissues have been considered according to realistic values. Simulations have been performed at 1 MHz, 10 MHz and 21 MHz. Results showed that the electrical properties of the tissues have different variations at the operating frequencies, and as a result of this, it has been shown that the behavior of the signal in the tissue has changed. Electric field distributions have been obtained mostly in tissue layers close to the electrodes for all three frequencies. Maximum current density has been induced in muscle tissue for 1 MHz, whereas it has been observed in skin tissue for 10 MHz and 21 MHz.

There is a tremendous increase in use of RF electronics in veterinary for tracking and health che... more There is a tremendous increase in use of RF electronics in veterinary for tracking and health check of animals. The mechanisms of magnetic and electromagnetic effects in biological systems are known, effect of electromagnetics in biological tissues are generally studied in human tissues in the literature, and the mechanism was convincingly established for enzymatic adenosine triphosphate (ATP) and desoxynucleic acid (DNA) synthesis. In this study, the SAR effect of pH boluses used to monitor the rumen pH value of animals has been tried to be revealed. For this purpose, active RFID tags operating at 434 MHz have been placed in the rumen zone by adding a pH sensor and the rumen pH values have been monitored dynamically for two months. The SAR value generated by active RFID tag antennas with 1 mW output power has been modeled with the help of a simulation program. The resulting SAR effect appears to be well below the legal limit. Keywords— SAR, Active RFID Tags, pH bolus.

Scientific Research and Essays, 2013

The polynomial-based differential quadrature method (PDQM) and Fourier expansion-based differenti... more The polynomial-based differential quadrature method (PDQM) and Fourier expansion-based differential quadrature method (FDQM) are examined to solve 2D Helmholtz problem expressing definition of many electromagnetic problems. PDQM and FDQM solution of the problems were calculated and compared, analytically. While grid node and wave number are steady, the PDQM and FDQM were applied to 2D Helmholtz problem for calculation and comparison. While the grid node is equal to 7 (N=M=7) and the wave number is equal to 1 (k=1), (maximum absolute error between the numerical result and the exact solution) for PDQM and for FDQM has been found as 2.758×10-5 and 2.921×10-6 respectively. Then wave number was increased in order to examine the effects of its variation to the accuracy, while grid node was kept in steady state. While grid node was steady and equal to 7 and the wave number was increased from 1 to 5, for FDQM has been found as 2.921×10-6, 7.995×10-5, 1.020×10-4, 0.1825 and 1.779 respectiv...

In this study, planar near-fleld antenna measurement system has been used as a controlled radar s... more In this study, planar near-fleld antenna measurement system has been used as a controlled radar setup and bistatic wave scattering conditions have been formed. A metal having 1cm £ 5cm dimensions has been buried in a non-conductive cylinder having a diameter of 5cm and height of 10cm. Then, electromagnetic scattering pattern of cylinder has been obtained by using S21 parameter. Using some image processing techniques on obtained pattern, detection of the metal buried in cylinder has been realized. The detection of buried objects in other mediums is important since there are many related appli- cations such as security, military, and medical applications. This issue force scientists to conduct researches on similar issues (1{3). Marr etal. (1) investigated the scattering characteristic of the metallic sphere by using cylindrical near fleld scanning system. They investigated the radar cross section and pattern of the sphere by putting it in the center of the scanner They compared numerical solutions with far fleld data computed from measured near fleld. Amineh etal. (2) investigated the capabilities and limits of the horn antennas flrst and then they proposed a microwave imaging setup by using planar aperture raster scanning. They used blind de-convolution algorithm and tested the performance of their technique. Burkholder etal. (3) used model-based imaging method instead of conventional imaging ap- proaches and they investigated the detection of objects inside a room. Since the topic has many applications, it is important to develop an e-cient technique. In this study, buried metal detection has been realized by using a planar near fleld antenna measurement system, which is mainly used for measuring and testing antennas, as a bistatic radar setup. Also, image processing techniques have been used.

Radiation Protection Dosimetry, 2021

In this study, electric field and magnetic field strengths at 50 Hz are measured in a solar power... more In this study, electric field and magnetic field strengths at 50 Hz are measured in a solar power plant located far from residential areas, and the measurement results near various sources of the electric and magnetic fields in the power plant are presented. Although the measured values for the electric field caused by the solar panel range between 0.07 and 1.33 V/m, the measured values for the magnetic field by the solar panel range between 0.037 and 0.19 μT. In front of the inverter, the measured value of the electric field reaches 0.7 V/m, whereas the measured value of the magnetic field reaches 2.2 μT. The results are presented and evaluated in light of the exposure limits to electromagnetic fields published by international organisations.

International Journal Of Engineering & Applied Sciences, 2015

International Journal Of Engineering & Applied Sciences, 2015

International Journal of Occupational Safety and Ergonomics, 2021

Non-ionising dosimetry investigations of extremely low frequency (ELF) magnetic fields that are g... more Non-ionising dosimetry investigations of extremely low frequency (ELF) magnetic fields that are generated by underground power cables as well as the minimisation of their health effects are significant topics handled by numerous researchers. In this study, ELF magnetic fields and current densities caused by three-phased underground transmission lines induced in the human model were examined utilising both analytical and numerical methods. Analyses were carried out using a two-dimensional problem scenario for the comprehensive head and body model. The results of the finite element method-based (FEM) simulation studies and the analytical calculations are consistent with each other. Moreover, a magnetic field shielding method utilising conductive material was presented in the study. The shielding technique performed with copper material was carried out to mitigate the magnetic field and possible dosimetry hazards in the ELF region. The proposed shield was a four millimetre (mm) reversed-U-shaped copper material.

Nowadays, complex electromagnetic scenarios carried out by numerical techniques can be solved eas... more Nowadays, complex electromagnetic scenarios carried out by numerical techniques can be solved easily by state-of-the-art technology computers. Thus, many numerical techniques have been emerged in order to solve the different problems. In this way, scientists can define and predict the various circumstances for any problem. In this study, a microstrip patch antenna has been analyzed by using finite difference time domain (FDTD) method which is the one of the most utilized technique in computational electromagnetics. Antenna has been fed through the Gaussian pulse from the microstrip line. Microstrip patch antenna has been designed as three layered structure which are ground, substrate and patch. Although the ground and patch layers have been selected as perfectly electric conductor (PEC), substrate layer has been selected as a dielectric material whose dielectric constant has been 4.4. Also, designed antenna has been surrounded by perfectly matched layer (PML). FDTD based investigati...

IEEE Antennas and Wireless Propagation Letters, 2008

Mühendislik Bilimleri ve Tasarım Dergisi, 2020

2017 Progress In Electromagnetics Research Symposium - Spring (PIERS)

The characteristic parameters of the lightning electromagnetic pulse (LEMP) current have been inv... more The characteristic parameters of the lightning electromagnetic pulse (LEMP) current have been investigated for many years on the basis of the isolation coordination by scientists studying in the field of electricity and physics. The necessity of studying in this area has arisen in order to protect the electrical and electronic equipment inside the power transmission lines and electrical installations against the harmful effects of the harmonic current of the lightning electromagnetic pulse. In this study, the over-voltages, which occur due to the lightning electromagnetic wave strikes on the pylons, were investigated with the Alternative Transient Program (ATP). The Heidler function is used to simulate the LEMP model. Analyzes of the over-voltages that occur as a result of the lightning strike to the protection conductor on the top of a grounded pole or one of the pole conductors of the pylon are carried out. Moreover, high voltage, electric field and magnetic field changes in the environment where the lightning electromagnetic pulse strikes are analyzed numerically in MATLAB using Rusk equations and compared with ATP simulation results.