This paper analyses the change of electric field in the proximity of 500 kV extra high voltage
(EHV) transmission lines, in the presence of raindrops and dew. The computations were carried out using
MatLab software by solving the electrostatic equations. The analysis depicts that the spatial distribution of
the electric field strength varies with water drop content along the lateral distance along the transmiss ion
line. The peak electric field reduces with the water drop content, whereas the electric field remains the
same at around 36 m from the transmission line. Then onwards the field strength increases with the water
drop content. At long distances the field strength is not affected by the water drops. Such variation is highly
important to analyse the adverse effects on the insulators used in HV applications. The results are of high
significance to a country such as Indonesia where the precipitation levels are generally high in most parts
of the country.
The Effect of High Zeta Potentials on the Flow Hydrodynamics in Parallel-Plat...CSCJournals
This paper investigates the effect of the EDL at the solid-liquid interface on the liquid flow through a micro-channel formed by two parallel plates. The complete Poisson-Boltzmann equation (without the frequently used linear approximation) was solved analytically in order to determine the EDL field near the solid-liquid interface. The momentum equation was solved analytically taking into consideration the electrical body force resulting from the EDL field. Effects of the channel size and the strength of the zeta-potential on the electrostatic potential, the streaming potential, the velocity profile, the volume flow rate, and the apparent viscosity are presented and discussed. Results of the present analysis, which are based on the complete Poisson-Boltzmann equation, are compared with a simplified analysis that used a linear approximation of the Poisson-Boltzmann equation.
Reduced Dielectric Losses for Underground Cable Distribution SystemsIJAPEJOURNAL
This paper describes the process to reduce dielectric losses for underground cable distribution system. As already known, that system is an alternative solution to energy distribution systems in urban areas. Influence of large capacitance is a separate issue that needs to be resolved.
Large capacitance effect on Express Feeder of 10 miles long has resulted in power losses more than 100 MW per month. In the no-load condition, current dispatch has recorded 10 Amperes, and has increased the voltage at receiving end by 200-500 Volts, with leading power factors.
Installation of the inductor to reduce cable loss dielectrics is done by changing the power factor (pf) to 0.85 lagging. After installation of the inductor, which is 5 mH/700 kVAR, dielectric losses is reduced to 3.57%, which is from 105,983 kW to 102,195 kWh per month. The capacitive leakage current has also been reduced from 249.61 Ampere to 245.17 Ampere.
Electric potential gradient fractal dimension for characterizing shajara rese...Khalid Al-Khidir
1. The document analyzes fractal dimensions derived from electric potential gradient and capillary pressure measurements on sandstone samples from the Shajara Formation in Saudi Arabia.
2. Equations relating wetting phase saturation, electric potential gradient, maximum gradient, and fractal dimension were developed and used to calculate fractal dimension from log-log plots. Fractal dimension was also calculated from the relationship between capillary pressure and wetting phase saturation.
3. Results showed that the electric potential gradient fractal dimension was equal to the capillary pressure fractal dimension. Higher fractal dimensions correlated with higher permeability and were found in the Upper Shajara Reservoir units, indicating more heterogeneous and interconnected pore spaces.
Modelling Quantum Transport in Nanostructuresiosrjce
IOSR Journal of Electronics and Communication Engineering(IOSR-JECE) is a double blind peer reviewed International Journal that provides rapid publication (within a month) of articles in all areas of electronics and communication engineering and its applications. The journal welcomes publications of high quality papers on theoretical developments and practical applications in electronics and communication engineering. Original research papers, state-of-the-art reviews, and high quality technical notes are invited for publications.
Quantum transport in semiconductor nanostructuressamrat saurabh
This document discusses quantum transport in semiconductor nanostructures. It begins by providing background on semiconductors, including their electrical properties between conductors and insulators. When sized below a certain limit, nanostructures constructed from semiconductors exhibit new electronic and optical properties due to quantization effects. An example is a quantum dot formed from a semiconductor with 5-10nm thickness. The document then discusses different types of quantum transport, including diffusive and ballistic transport, and provides examples of applications of semiconductor nanostructures in areas like lasers and quantum computing.
Types of conductors, line parameters, calculation of inductance and capacitance of single and double circuit transmission lines, three phase lines with bundle conductors. Skin effect and
proximity effect.
The Effect of High Zeta Potentials on the Flow Hydrodynamics in Parallel-Plat...CSCJournals
This paper investigates the effect of the EDL at the solid-liquid interface on the liquid flow through a micro-channel formed by two parallel plates. The complete Poisson-Boltzmann equation (without the frequently used linear approximation) was solved analytically in order to determine the EDL field near the solid-liquid interface. The momentum equation was solved analytically taking into consideration the electrical body force resulting from the EDL field. Effects of the channel size and the strength of the zeta-potential on the electrostatic potential, the streaming potential, the velocity profile, the volume flow rate, and the apparent viscosity are presented and discussed. Results of the present analysis, which are based on the complete Poisson-Boltzmann equation, are compared with a simplified analysis that used a linear approximation of the Poisson-Boltzmann equation.
Reduced Dielectric Losses for Underground Cable Distribution SystemsIJAPEJOURNAL
This paper describes the process to reduce dielectric losses for underground cable distribution system. As already known, that system is an alternative solution to energy distribution systems in urban areas. Influence of large capacitance is a separate issue that needs to be resolved.
Large capacitance effect on Express Feeder of 10 miles long has resulted in power losses more than 100 MW per month. In the no-load condition, current dispatch has recorded 10 Amperes, and has increased the voltage at receiving end by 200-500 Volts, with leading power factors.
Installation of the inductor to reduce cable loss dielectrics is done by changing the power factor (pf) to 0.85 lagging. After installation of the inductor, which is 5 mH/700 kVAR, dielectric losses is reduced to 3.57%, which is from 105,983 kW to 102,195 kWh per month. The capacitive leakage current has also been reduced from 249.61 Ampere to 245.17 Ampere.
Electric potential gradient fractal dimension for characterizing shajara rese...Khalid Al-Khidir
1. The document analyzes fractal dimensions derived from electric potential gradient and capillary pressure measurements on sandstone samples from the Shajara Formation in Saudi Arabia.
2. Equations relating wetting phase saturation, electric potential gradient, maximum gradient, and fractal dimension were developed and used to calculate fractal dimension from log-log plots. Fractal dimension was also calculated from the relationship between capillary pressure and wetting phase saturation.
3. Results showed that the electric potential gradient fractal dimension was equal to the capillary pressure fractal dimension. Higher fractal dimensions correlated with higher permeability and were found in the Upper Shajara Reservoir units, indicating more heterogeneous and interconnected pore spaces.
Modelling Quantum Transport in Nanostructuresiosrjce
IOSR Journal of Electronics and Communication Engineering(IOSR-JECE) is a double blind peer reviewed International Journal that provides rapid publication (within a month) of articles in all areas of electronics and communication engineering and its applications. The journal welcomes publications of high quality papers on theoretical developments and practical applications in electronics and communication engineering. Original research papers, state-of-the-art reviews, and high quality technical notes are invited for publications.
Quantum transport in semiconductor nanostructuressamrat saurabh
This document discusses quantum transport in semiconductor nanostructures. It begins by providing background on semiconductors, including their electrical properties between conductors and insulators. When sized below a certain limit, nanostructures constructed from semiconductors exhibit new electronic and optical properties due to quantization effects. An example is a quantum dot formed from a semiconductor with 5-10nm thickness. The document then discusses different types of quantum transport, including diffusive and ballistic transport, and provides examples of applications of semiconductor nanostructures in areas like lasers and quantum computing.
Types of conductors, line parameters, calculation of inductance and capacitance of single and double circuit transmission lines, three phase lines with bundle conductors. Skin effect and
proximity effect.
Analysis of Pseudogap in SuperconductorsIOSR Journals
The document analyzes the effect of the pseudogap on the static magnetic susceptibility of the high-temperature superconductor YBa2Cu3O7-δ. Magnetic susceptibility measurements were taken for various levels of oxygen deficiency δ, corresponding to different hole concentrations p. The data shows anomalous suppression of magnetic susceptibility above the critical temperature Tc in the underdoped region, indicative of the presence of a pseudogap. Analysis of the temperature and doping dependence of the magnetic susceptibility provides information about the pseudogap energy scale and its variation with hole concentration p.
Electrical Resistivity Survey Forground Water At Eye Zheba Village, Off Bida ...iosrjce
The paper titled “Electrical Resistivity survey for ground water” at EL-HALAL Farms, covered an
area of about 10km2
, located at Eye Zheba village along Minna-Bida Road, located on latitude 60
.001
and 6
0
7
1
West and longitude 90
3
1
and 9.101 North. As a result of water problem in Bida and its environs, the people living
in this environment suffered a lot due to lack of portable drinking water and water for domestic use. A
Geophysical survey carried out, employed the schlumberger Array method in which current were sent beneath
the earth surfaces, this was done at various points and the data collected. The area revealed three lithological
formations in some places while in some place five. With the lowest resistivty found to be 6.85 Ωm and the
highest resistivity was 12,774.46 Ωm. The lithotogical formation includes the sandstones, clayey sandstones,
sandy clay and ferruginised sandstone. Since this is a sedimentary area drilling is expected to be deep down to a
depth of about 70-75m
POWER SUPPLY SYSTEMS& DISTRIBUTION SYSTEMSDuddu Rajesh
Transmission and distribution systems- D.C 2-wire and 3- wire systems, A.C single phase, three phase and 4-wire systems, comparison of copper efficiency. Primary and secondary
distribution systems, concentrated & uniformly distributed loads on distributors fed at both ends, ring distributor, voltage drop and power loss calculation, Kelvin’slaw.
This document summarizes the results of a Monte Carlo simulation comparing electron transport properties in GaSb and GaAs semiconductors at high electric fields. The simulation includes nonparabolic band structures, acoustic and polar optical phonon scattering, and ionized impurity scattering. It finds that GaAs has a higher peak electron drift velocity of around 2.2x105 m/s compared to 1.2x105 m/s for GaSb. Both materials show velocity saturation at high fields due to increased intervalley scattering. Temperature is also found to decrease peak velocity and increase the critical field for velocity overshoot.
3D resistivity imaging uses multi-electrode systems to allow three-dimensional reconstruction of subsurface structures. It has advantages over 2D resistivity imaging in detecting complex underground features. The document discusses 3D resistivity imaging techniques, including:
- Inversion of large data sets using faster computers to model subsurface resistivity in small blocks
- Common electrode arrays like pole-pole, pole-dipole, and dipole-dipole
- Sensitivity patterns that make some arrays better for detecting off-axis underground objects
- Procedures for field measurement and combining multiple 2D data sets for 3D inversion modeling
This document discusses methods for measuring soil resistivity, which is an important factor in determining corrosion rates. It describes two key methods: (1) the Wenner four-pin method, where four pins are placed in the soil in a line and current is passed between the outer pins to measure voltage between the inner pins and calculate resistivity; and (2) the soil box method, where a soil sample is placed in a metal box and contacts make measurements to determine resistivity using the sample's dimensions. Both methods apply Ohm's Law and equations to calculate resistivity from resistance measurements. Temperature also affects resistivity, so measurements should not be taken below freezing.
1-D Electrical Resistivity Survey For Groundwater In Ketu-Adie Owe, Ogun Stat...iosrjce
This research involved the use of 1-D electrical resistivity survey method for groundwater
investigation in Ketu-Adie Owe, Ogun State. Seven (7) vertical electrical resistivity soundings (VES) using
Schlumberger array were carried out at different locations. The Schlumberger resistivity soundings were
executed with half-spacing in the range of 1.00 – 100.00 metres. The curve types are AAK, AAK, KHAK, AKQ,
KQH, AK. The study shows that viable aquifer is within 17.30 – 52.90 metres square.
This presentation discusses electrical resistivity methods for geophysical surveying. It describes how resistivity utilizes differences in electric potential to image the subsurface. Key concepts covered include Ohm's law, electrode configurations like Wenner and Schlumberger arrays, methods like vertical electrical sounding and electric profiling, and instrumentation used including current sources, resistivity meters, and electrode types. Applications mentioned are groundwater detection, mineral exploration, and waste exploration.
This document discusses the modeling of electric and magnetic fields under high voltage AC transmission lines. It begins by introducing the importance of modeling these fields and some of the factors that influence field strength. It then provides equations to calculate the electric field based on the method of images technique, accounting for parameters like conductor voltage, geometry, and distance from measuring point. Similar equations are given for calculating the magnetic field based on conductor current. The document emphasizes that these fields can induce currents and charges in nearby objects, and discusses how to calculate the induced short circuit current. The goal of the modeling is to understand safer operating practices near transmission lines.
THE STUDY ON THE PLASMA GENERATOR THEORY FOR THIN DISC AND THIN RING CONFIGUR...AM Publications
Various corona discharges plasma generators equipment have been composed with significant ability to produce saturation current effect. The effect was generated by the potential difference of the capacitive system where two electrodes are set with opposite charges to each other. The saturation current occurring in this capacitive electrode system can be generated by a small voltage source (about 12 volts). A sufficiently large electric field and a saturation current, can be obtained from a configuration of sharp electrodes. An example of the electrode shape is a configuration of a very thin and sharp disc surrounded by a ring electrode in a two-dimensional space. The value of the electric field and the saturation current will be calculated in mentioned electrode configuration.
Electrical resistivity data interpretation for groundwater detection in titta...eSAT Journals
Abstract The present study aims to detect the groundwater potential in Tittagudi Taluk of Cuddalore District, Tamil Nadu, India using electrical measurement. Electric resistivity data interpretation was carried out using Schlumberger configuration with electrode spacing (AB/2) of 100 m distance. The VES was calculated by multiplying the resistance by constant obtained from the Schlumberger formula. The resistivity curves were analysed with curve matching techniques along with the help of computer programme. The sub-surface lithology was evaluated and correlated with the available borehole data. The results of quantitative interpretation of geoelectrical data indicated that the layer system having minimum of two layers to a maximum of eight layers in the area. The low and high resistivities obtained are ranging from 0.5 to 27755 ohm/m respectively. Majority of resistivity curves are falling in ‘A’ type. The contact zone of sedimentary and crystalline rock formations are clearly delineated on Northeast to Southwest directions along Sirumangalam, Agaram and Sirumalai habitations. The prominent low resistivity anomaly observed in and around Adari area (VES. 03), this have been encountered in all the iso-resistivity contour maps, indicating that, a trend of structural elements like a weaker zone or lineament or fracture occurred in NE direction of the study area which may be a favorable zone for targeting groundwater. Key words: Electrical Measurements, Tittagudi Taluk, Schulmberger Configuration And Iso-Resistivity Maps.
The AC total interference of faulted power lines to gas pipelines sharing the same right of way, which may pose a threat to operating personnel and equipment, was studied. The main advantage of this work is to determine the effects of different soil structures on the induced voltage for various soil resistivities. Two main approaches were used to compute the induced voltages, namely the method of moment (MOM), which is based on electromagnetic field theory, and the circuit based method, which uses the circuit grounding analysis to compute the conductive interference and the circuit based models to compute the inductive interference. A 10-km-long parallel pipeline-transmission line model was developed. The soil resistivity was varied, and the induced voltages obtained from both approaches were compared. Soil resistivity and soil structure are important parameters that affect the AC interference level. The results of the study show that the earth potentials and the metal GPRS are independent. Higher soil resistivity causes the tower ground resistance to increase, thus making the shield wire’s attractiveness as a fault current return path to increase, which in turn forces the induced net EMF and the cumulative GPR in the pipeline to reduce.
To perform geological exploration by the geophysical method of electrical resistivity.
The objective of this research is to evaluate the water potential of the study area by investigating the shallow subsurface aquifer material properties and moisture distribution using 2D ERT techniques. During the shallow tube well design and development in the study area, some patches of land does have good potential and some does not, which motivated to understand the aquifer properties, aquifer material, and response. Hence the 2D ERT was carried out, oriented around the pond in the center and five ERT profiles.
This Lecture includes the Resistivity survey, field procedure, application advantage, limitaion, Apparant resistivity, VES (Vertical Electrical Sounding), Resistivity Profiling and IP Survey in brief.
Effect of earth on transmission line, bundle conductor & method of gmdvishalgohel12195
Effect of earth on transmission line, Bundle conductor & Method of GMD
EFFECTS OF EARTH ON THE CAPACITANCE OF THREE PHASE TRANSMISSION LINES
Bundle Conductors
H-mode-like confinement formation in the RF discharge plasma in the Uragan-3M...Aleksey Beletskii
This PhD thesis studied plasma confinement and heating in the Uragan-3M torsatron device. Experiments varied RF power levels and plasma densities. At RF powers over 100 kW and densities around 1.2×1012 cm-3, signs of improved confinement similar to the H-mode transition were observed, including increased density, temperature, and stored energy. Faster processes like an electric field bifurcation and turbulence suppression triggered the transition, while slower processes like increasing fast ion content and density decay preceded it. Detailed edge plasma turbulence measurements found fluctuations suppressed after the transition. The fast ion loss appears to trigger the transition by initiating the electric field bifurcation. Further study of fast ion generation mechanisms could provide more insight.
This document provides a review of High Electron Mobility Transistors (HEMTs). It discusses the motivation for developing HEMTs due to limitations of silicon MOSFETs and III-V MESFETs. The basic working principles of HEMTs are presented using the AlGaAs/GaAs material system, including the formation of a two-dimensional electron gas (2DEG) at the heterojunction interface which provides high electron mobility. Early developments of HEMTs in the 1980s by researchers at institutions including Fujitsu, Bell Labs, and the University of Illinois are summarized. More recent developments involving GaN HEMTs and MOSHEMT structures are also reviewed.
Transient response of grounding systems under impulse lightning currentHimmelstern
This document summarizes research on modeling the transient response of grounding systems during lightning strikes. It develops a lumped parameter model using transmission line theory to represent the distributed parameters of grounding conductors. The model accounts for time-varying soil properties like resistivity and ionization around electrodes during high current injections. Simulation results show the model can accurately estimate voltages along the grounding system under different lightning impulse currents and validate analytical methods.
1) The document presents the results of tests on a new method for de-icing high voltage transmission lines after severe ice storms. The method involves circulating a short-circuit current at the rated voltage of the lines to create electromagnetic forces that cause the conductors to knock against each other and dislodge ice.
2) Tests were conducted on sample overhead transmission lines with twin conductors (315 kV) and quad conductors (735 kV) installed at a high-power laboratory. The impacts on power system stability and power quality are also examined.
3) The test results show that the new de-icing method was effective in removing ice from conductors. For twin conductors, 30-70%
Application of LFAC { Hz} for electrical power transmission system: a compara...TELKOMNIKA JOURNAL
This document presents a simulation study comparing 50Hz and 16.67Hz frequencies for electrical power transmission. Two transmission systems were modeled in MATLAB/Simulink: one at 50Hz and one at 16.67Hz. Transmission lines of 50km, 150km, and 300km were used. Simulation results showed lower losses with 16.67Hz frequency, demonstrating it is better than 50Hz for energy savings. Low frequency AC transmission is currently used in some European countries for electric vehicles, but this study examines its application for long-distance bulk power transmission.
Partially filled electrode for DMF devicesWaleed Salman
This document describes research into partially filled electrodes for digital microfluidic devices. The researchers conducted simulations and experiments to evaluate how reducing the filled area of electrodes affects actuation forces on droplets. The simulations showed that actuation force decreases linearly as electrode fill percentage decreases. However, forces were independent of the vertical location of removed electrode areas. Experiments confirmed that partially filled electrodes can still achieve droplet actuation speeds sufficient for many applications, with frequencies over 10 electrodes per second achieved at 40% fill area. Partially filled electrodes also allow integration of additional on-chip elements and transmission microscopy imaging of droplets.
Analysis of Pseudogap in SuperconductorsIOSR Journals
The document analyzes the effect of the pseudogap on the static magnetic susceptibility of the high-temperature superconductor YBa2Cu3O7-δ. Magnetic susceptibility measurements were taken for various levels of oxygen deficiency δ, corresponding to different hole concentrations p. The data shows anomalous suppression of magnetic susceptibility above the critical temperature Tc in the underdoped region, indicative of the presence of a pseudogap. Analysis of the temperature and doping dependence of the magnetic susceptibility provides information about the pseudogap energy scale and its variation with hole concentration p.
Electrical Resistivity Survey Forground Water At Eye Zheba Village, Off Bida ...iosrjce
The paper titled “Electrical Resistivity survey for ground water” at EL-HALAL Farms, covered an
area of about 10km2
, located at Eye Zheba village along Minna-Bida Road, located on latitude 60
.001
and 6
0
7
1
West and longitude 90
3
1
and 9.101 North. As a result of water problem in Bida and its environs, the people living
in this environment suffered a lot due to lack of portable drinking water and water for domestic use. A
Geophysical survey carried out, employed the schlumberger Array method in which current were sent beneath
the earth surfaces, this was done at various points and the data collected. The area revealed three lithological
formations in some places while in some place five. With the lowest resistivty found to be 6.85 Ωm and the
highest resistivity was 12,774.46 Ωm. The lithotogical formation includes the sandstones, clayey sandstones,
sandy clay and ferruginised sandstone. Since this is a sedimentary area drilling is expected to be deep down to a
depth of about 70-75m
POWER SUPPLY SYSTEMS& DISTRIBUTION SYSTEMSDuddu Rajesh
Transmission and distribution systems- D.C 2-wire and 3- wire systems, A.C single phase, three phase and 4-wire systems, comparison of copper efficiency. Primary and secondary
distribution systems, concentrated & uniformly distributed loads on distributors fed at both ends, ring distributor, voltage drop and power loss calculation, Kelvin’slaw.
This document summarizes the results of a Monte Carlo simulation comparing electron transport properties in GaSb and GaAs semiconductors at high electric fields. The simulation includes nonparabolic band structures, acoustic and polar optical phonon scattering, and ionized impurity scattering. It finds that GaAs has a higher peak electron drift velocity of around 2.2x105 m/s compared to 1.2x105 m/s for GaSb. Both materials show velocity saturation at high fields due to increased intervalley scattering. Temperature is also found to decrease peak velocity and increase the critical field for velocity overshoot.
3D resistivity imaging uses multi-electrode systems to allow three-dimensional reconstruction of subsurface structures. It has advantages over 2D resistivity imaging in detecting complex underground features. The document discusses 3D resistivity imaging techniques, including:
- Inversion of large data sets using faster computers to model subsurface resistivity in small blocks
- Common electrode arrays like pole-pole, pole-dipole, and dipole-dipole
- Sensitivity patterns that make some arrays better for detecting off-axis underground objects
- Procedures for field measurement and combining multiple 2D data sets for 3D inversion modeling
This document discusses methods for measuring soil resistivity, which is an important factor in determining corrosion rates. It describes two key methods: (1) the Wenner four-pin method, where four pins are placed in the soil in a line and current is passed between the outer pins to measure voltage between the inner pins and calculate resistivity; and (2) the soil box method, where a soil sample is placed in a metal box and contacts make measurements to determine resistivity using the sample's dimensions. Both methods apply Ohm's Law and equations to calculate resistivity from resistance measurements. Temperature also affects resistivity, so measurements should not be taken below freezing.
1-D Electrical Resistivity Survey For Groundwater In Ketu-Adie Owe, Ogun Stat...iosrjce
This research involved the use of 1-D electrical resistivity survey method for groundwater
investigation in Ketu-Adie Owe, Ogun State. Seven (7) vertical electrical resistivity soundings (VES) using
Schlumberger array were carried out at different locations. The Schlumberger resistivity soundings were
executed with half-spacing in the range of 1.00 – 100.00 metres. The curve types are AAK, AAK, KHAK, AKQ,
KQH, AK. The study shows that viable aquifer is within 17.30 – 52.90 metres square.
This presentation discusses electrical resistivity methods for geophysical surveying. It describes how resistivity utilizes differences in electric potential to image the subsurface. Key concepts covered include Ohm's law, electrode configurations like Wenner and Schlumberger arrays, methods like vertical electrical sounding and electric profiling, and instrumentation used including current sources, resistivity meters, and electrode types. Applications mentioned are groundwater detection, mineral exploration, and waste exploration.
This document discusses the modeling of electric and magnetic fields under high voltage AC transmission lines. It begins by introducing the importance of modeling these fields and some of the factors that influence field strength. It then provides equations to calculate the electric field based on the method of images technique, accounting for parameters like conductor voltage, geometry, and distance from measuring point. Similar equations are given for calculating the magnetic field based on conductor current. The document emphasizes that these fields can induce currents and charges in nearby objects, and discusses how to calculate the induced short circuit current. The goal of the modeling is to understand safer operating practices near transmission lines.
THE STUDY ON THE PLASMA GENERATOR THEORY FOR THIN DISC AND THIN RING CONFIGUR...AM Publications
Various corona discharges plasma generators equipment have been composed with significant ability to produce saturation current effect. The effect was generated by the potential difference of the capacitive system where two electrodes are set with opposite charges to each other. The saturation current occurring in this capacitive electrode system can be generated by a small voltage source (about 12 volts). A sufficiently large electric field and a saturation current, can be obtained from a configuration of sharp electrodes. An example of the electrode shape is a configuration of a very thin and sharp disc surrounded by a ring electrode in a two-dimensional space. The value of the electric field and the saturation current will be calculated in mentioned electrode configuration.
Electrical resistivity data interpretation for groundwater detection in titta...eSAT Journals
Abstract The present study aims to detect the groundwater potential in Tittagudi Taluk of Cuddalore District, Tamil Nadu, India using electrical measurement. Electric resistivity data interpretation was carried out using Schlumberger configuration with electrode spacing (AB/2) of 100 m distance. The VES was calculated by multiplying the resistance by constant obtained from the Schlumberger formula. The resistivity curves were analysed with curve matching techniques along with the help of computer programme. The sub-surface lithology was evaluated and correlated with the available borehole data. The results of quantitative interpretation of geoelectrical data indicated that the layer system having minimum of two layers to a maximum of eight layers in the area. The low and high resistivities obtained are ranging from 0.5 to 27755 ohm/m respectively. Majority of resistivity curves are falling in ‘A’ type. The contact zone of sedimentary and crystalline rock formations are clearly delineated on Northeast to Southwest directions along Sirumangalam, Agaram and Sirumalai habitations. The prominent low resistivity anomaly observed in and around Adari area (VES. 03), this have been encountered in all the iso-resistivity contour maps, indicating that, a trend of structural elements like a weaker zone or lineament or fracture occurred in NE direction of the study area which may be a favorable zone for targeting groundwater. Key words: Electrical Measurements, Tittagudi Taluk, Schulmberger Configuration And Iso-Resistivity Maps.
The AC total interference of faulted power lines to gas pipelines sharing the same right of way, which may pose a threat to operating personnel and equipment, was studied. The main advantage of this work is to determine the effects of different soil structures on the induced voltage for various soil resistivities. Two main approaches were used to compute the induced voltages, namely the method of moment (MOM), which is based on electromagnetic field theory, and the circuit based method, which uses the circuit grounding analysis to compute the conductive interference and the circuit based models to compute the inductive interference. A 10-km-long parallel pipeline-transmission line model was developed. The soil resistivity was varied, and the induced voltages obtained from both approaches were compared. Soil resistivity and soil structure are important parameters that affect the AC interference level. The results of the study show that the earth potentials and the metal GPRS are independent. Higher soil resistivity causes the tower ground resistance to increase, thus making the shield wire’s attractiveness as a fault current return path to increase, which in turn forces the induced net EMF and the cumulative GPR in the pipeline to reduce.
To perform geological exploration by the geophysical method of electrical resistivity.
The objective of this research is to evaluate the water potential of the study area by investigating the shallow subsurface aquifer material properties and moisture distribution using 2D ERT techniques. During the shallow tube well design and development in the study area, some patches of land does have good potential and some does not, which motivated to understand the aquifer properties, aquifer material, and response. Hence the 2D ERT was carried out, oriented around the pond in the center and five ERT profiles.
This Lecture includes the Resistivity survey, field procedure, application advantage, limitaion, Apparant resistivity, VES (Vertical Electrical Sounding), Resistivity Profiling and IP Survey in brief.
Effect of earth on transmission line, bundle conductor & method of gmdvishalgohel12195
Effect of earth on transmission line, Bundle conductor & Method of GMD
EFFECTS OF EARTH ON THE CAPACITANCE OF THREE PHASE TRANSMISSION LINES
Bundle Conductors
H-mode-like confinement formation in the RF discharge plasma in the Uragan-3M...Aleksey Beletskii
This PhD thesis studied plasma confinement and heating in the Uragan-3M torsatron device. Experiments varied RF power levels and plasma densities. At RF powers over 100 kW and densities around 1.2×1012 cm-3, signs of improved confinement similar to the H-mode transition were observed, including increased density, temperature, and stored energy. Faster processes like an electric field bifurcation and turbulence suppression triggered the transition, while slower processes like increasing fast ion content and density decay preceded it. Detailed edge plasma turbulence measurements found fluctuations suppressed after the transition. The fast ion loss appears to trigger the transition by initiating the electric field bifurcation. Further study of fast ion generation mechanisms could provide more insight.
This document provides a review of High Electron Mobility Transistors (HEMTs). It discusses the motivation for developing HEMTs due to limitations of silicon MOSFETs and III-V MESFETs. The basic working principles of HEMTs are presented using the AlGaAs/GaAs material system, including the formation of a two-dimensional electron gas (2DEG) at the heterojunction interface which provides high electron mobility. Early developments of HEMTs in the 1980s by researchers at institutions including Fujitsu, Bell Labs, and the University of Illinois are summarized. More recent developments involving GaN HEMTs and MOSHEMT structures are also reviewed.
Transient response of grounding systems under impulse lightning currentHimmelstern
This document summarizes research on modeling the transient response of grounding systems during lightning strikes. It develops a lumped parameter model using transmission line theory to represent the distributed parameters of grounding conductors. The model accounts for time-varying soil properties like resistivity and ionization around electrodes during high current injections. Simulation results show the model can accurately estimate voltages along the grounding system under different lightning impulse currents and validate analytical methods.
1) The document presents the results of tests on a new method for de-icing high voltage transmission lines after severe ice storms. The method involves circulating a short-circuit current at the rated voltage of the lines to create electromagnetic forces that cause the conductors to knock against each other and dislodge ice.
2) Tests were conducted on sample overhead transmission lines with twin conductors (315 kV) and quad conductors (735 kV) installed at a high-power laboratory. The impacts on power system stability and power quality are also examined.
3) The test results show that the new de-icing method was effective in removing ice from conductors. For twin conductors, 30-70%
Application of LFAC { Hz} for electrical power transmission system: a compara...TELKOMNIKA JOURNAL
This document presents a simulation study comparing 50Hz and 16.67Hz frequencies for electrical power transmission. Two transmission systems were modeled in MATLAB/Simulink: one at 50Hz and one at 16.67Hz. Transmission lines of 50km, 150km, and 300km were used. Simulation results showed lower losses with 16.67Hz frequency, demonstrating it is better than 50Hz for energy savings. Low frequency AC transmission is currently used in some European countries for electric vehicles, but this study examines its application for long-distance bulk power transmission.
Partially filled electrode for DMF devicesWaleed Salman
This document describes research into partially filled electrodes for digital microfluidic devices. The researchers conducted simulations and experiments to evaluate how reducing the filled area of electrodes affects actuation forces on droplets. The simulations showed that actuation force decreases linearly as electrode fill percentage decreases. However, forces were independent of the vertical location of removed electrode areas. Experiments confirmed that partially filled electrodes can still achieve droplet actuation speeds sufficient for many applications, with frequencies over 10 electrodes per second achieved at 40% fill area. Partially filled electrodes also allow integration of additional on-chip elements and transmission microscopy imaging of droplets.
Wireless power transfer using the concept of magnetic coil resonant systemTELKOMNIKA JOURNAL
Long life lithium ion batteries and methanol fuel cells have been persuaded as ways to make
the electrical components more mobile, consumers’ expectations are still far from being met due to
the added weight and expenses for battery replacement. The discovery of wireless power is transfered as
a new option, and holds great promise to leave the oversized battery. The design of wireless power
transfer applies the concept of magnetic coil resonant system (MCRS). The concept of MCRS is similar
with a function of an antenna to transfer the power from one point to another. Simulation process is used to
produce the output wave on the virtual oscilloscope and to obtain the reading of output voltage from
the multimeter. The transmitter side contains power supply, transmitter oscillator circuit and transmitter
magnetic coil. Transmitter circuit convert DC to AC waveform and the receiver circuit convert AC to DC
voltage. The DC Source that connected to transmitter was provided by the DC source regulator acts as DC
source to adjust voltage and current separately. The project show the efficiency of the wireless power
transfer with different coil diameter and a distance between the transmitter and receiver coil. At a distance
of 15 cm, power is successfully transmitted as it is indicated by the LED light to turn on. The increment of
size in coil diameter has given a higher power and longer coverage distance for wireless transfer power.
This study examines how liquid electrical properties (conductivity and permittivity) and the frequency of an applied voltage affect electrodynamic forces on droplets in digital microfluidic devices. The study finds that forces increase with conductivity up to 10-3 S/m and decrease significantly above a threshold frequency that depends on conductivity. Numerical simulations and experiments show that low conductivity liquids are best actuated at low frequencies while high conductivity liquids can be manipulated at higher frequencies without reducing forces. These results help optimize voltage and frequency for generating the strongest actuating forces on droplets.
Seawater salinity modelling based on electromagnetic wave characterizationIJECEIAES
Wireless communications have experienced tremendous growth, and improving their performance based on specific parameters requires an accurate model. Salt seawater, being an abundant resource, could play a crucial role in various applications such as enhancing electrical conductivity, monitoring security, improving battery power efficiency, and creating liquid antennas. Salinity is an essential factor to consider when developing these applications. This paper focused on investigating the electromagnetic properties of seawater salinity in the context of marine wireless communications. The results of the study showed that salinity has a significant impact on the Fresnel reflection coefficient in terms of magnitude, phase shift, and polarization, and can either constructively or destructively affect it. The new model paved the way for the development of an integrated salt seawater model that addressed the complex salinity issues involved in these applications.
Great pyramid giza alternative energy pg circular timestavennerpride
1) The authors have found that the dimensions of the Great Pyramid of Giza express key ratios related to sine waves and Fibonacci numbers. They hypothesize that the pyramid shape could function as a wideband antenna for capturing atmospheric electrostatic discharge (ESD) impulses.
2) Experiments show that a pyramid-shaped transducer can absorb ESD impulses from an electrostatic field and convert them into exponentially decaying sinusoidal waveforms.
3) Through an inductive coil system, the transducer is able to transfer power from the captured ESD impulses. Measurements indicate the system can achieve efficiencies of around 20-30% in transferring power.
Effect of HVTL Phase Transposition on Pipelines Induced Voltageijeei-iaes
In this work, a study of the effect of the phase conductor transposition for a multi-circuit high voltage power transmission lines on the induced voltage on a buried pipeline was conducted and considered through modelling. The modelling was done applying Carson’s concept of mutual impedances for a double circuit, three circuits and four circuit power transmission line on a buried pipeline. The simulated results obtained showed that the transmission line with un-transposed phase combination has the greater effect on the induced voltage while for the one or more of the other combinations, a cancellation or reduction can occur. This also is dependent on the tower geometry and the relative position of the pipeline and the transmission line. Also, the magnitude of the induced voltage increases with increasing number of circuits.
Quantum Current in Graphene Nano Scrolls Based Transistortheijes
Graphene based material application as a new centuery material are growing rappidly its carrier transport phenomenon with fast mobility have been focused resently. In the graphene family nanoscrolls because of their especial structure need to be explored. In the presented work a theoretical model for carrier transport in the arcemedus graphene nanoscrolls is reported. Graphene nanoscroll chairal dependent electrical property is considered and then schottky transistor based platform is modeled. The transport coeficient as a fundamental transport factor is discussed. The geometrical paprameter effect on the working phenomenon is considered as well.
This document proposes and validates an equivalent circuit model for a wireless power transfer system capable of transferring 220W of power over a 30cm air gap with 95% efficiency. The model represents the transmitter and receiver coils as inductors with low mutual coupling. Analytical expressions for the model are derived and validated using finite element analysis and experimental results. Loss analysis is also performed to investigate skin effect and proximity effect losses at high operating frequencies. A new coil spatial design is proposed to reduce such losses compared to conventional coil designs.
Space charges analysis on insulator with uniform layer contamination effectTELKOMNIKA JOURNAL
High voltage direct current (HVDC) transmission provides an attractive alternative for bulk power transfer. However, HVDC transmission may have loss about half per unit length of high voltage alternating current (HVAC) at the same amount of power carried. This is due to the space charge formation around the conductor in HVDC cables. It is known that the presence of space charge inside an insulator may distort the local electric field and surface energy. This paper investigates the effect of electrostatics for space charge, electric field and surface energy in the HVDC cable in clean and contaminated conditions. The effect of uniform layer contamination from oil, sandstone and fresh water was conducted on 11 kV XLPE cable using finite element software under electrostatics study. The contamination layer was created around the XLPE cable by multifarious the radius of layer contamination from the conductor. The simulation results show that enlargement of contamination layer radius by 1.0 mm (light), 1.5 mm (medium) and 2.0 mm (heavy) resulted in the reduction of surface energy by 20% and electric field by 22% but increase the space charge amplitude by 76%. The study also found that fresh water can be considered as the worst contamination compared to oil and sandstone.
The purpose of this paper is to study and design of 230 kV twin bundle double circuit overhead transmission line. In design consideration, the selection of economic voltage, choice of conductor size, number of insulators, maximum sag of conductor and minimum height of conductor are considered. The electrical transfer of energy from one place to another over long distance with standard regulations is one of the major problems in the field of electrical power engineering. The parameters of overhead transmission line are resistance, inductance and capacitance. The bundle conductors are used for reducing the reactance on the line, corona losses, radio interference and surge impedance. Daw Hnin Yu Lwin | U Hla Myo Htay "Design of 230 kV Twin Bundle Double Circuit Overhead Transmission Line" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-3 | Issue-5 , August 2019, URL: https://www.ijtsrd.com/papers/ijtsrd27830.pdfPaper URL: https://www.ijtsrd.com/engineering/electrical-engineering/27830/design-of-230-kv-twin-bundle-double-circuit-overhead-transmission-line/daw-hnin-yu-lwin
Lightning protection for overhead distribution linesGilberto Mejía
This document summarizes techniques for lightning protection of overhead power distribution lines. It discusses the types of lightning overvoltages that can occur on medium voltage (MV) and low voltage (LV) networks from direct strikes and indirect strikes. Direct strikes can cause overvoltages over 2000kV, far exceeding insulation levels and causing flashovers. Indirect strikes have lower but still significant voltages and are more common. The document reviews methods to mitigate these overvoltages, including increasing insulation, using grounded shield wires, and installing surge arresters. Shield wires and arresters are most effective at reducing faults from direct strikes, while all methods help reduce faults from indirect strikes.
The electromagnetic interferance caused by high voltage power lines along the...IJECEIAES
The identification of risks linked to electromagnetic compatibility (EMC) in the electric railway is a major concern in identifying EMC problems and analyzing the unintentional various external disturbing sources as well as the probability of occurrence of interference, the level of interference along the railway system. The purpose of this analysis is to determine the electromagnetic interaction coupling generated by the high voltage (HV) lines located along the railway line by analyzing the voltage induced in the signaling transmission cables such as the european rail traffic management system/european train control system (ERTMS/ETCS) through the multi-conductor transmission line (MTL) theory which may have an impact on the transmitting information. Dubanton method and approximate calculation will be applied and simulated through COMSOL Multiphysics tool in order to analyze if the protection distance and coupling conditions are respected by the railway standards.
Electrostatic fields and field stress controlvhasmukh96
This document discusses high voltage engineering and focuses on electric field distributions. It covers fields in homogeneous insulating materials like gases, fields in multi-dielectric materials, and numerical methods for solving field problems like the Finite Element Method. Specific topics include uniform fields, coaxial cylindrical and spherical fields, fields between spheres, and how conducting particles can distort fields. Fields in multi-layer dielectrics address configurations, dielectric refraction, and using screens to control stress.
Battery-Equivalent DC Supply from Leakage Current: PV to Transformer-less Inv...IAES-IJPEDS
The document discusses using leakage currents that occur in different places in a photovoltaic (PV) system with a transformer-less inverter topology to generate a battery-equivalent DC supply. It simulates the various leakage current paths that occur and uses a summer circuit to add the leakage currents together. The summed leakage current is then rectified using either a fully cross-coupled rectifier or gate cross-coupled rectifier and amplified to produce around 1V of DC voltage. This demonstrates that with proper circuitry, the leakage currents in a PV system can be harnessed to generate a small DC supply without needing a battery, thus providing a potential alternative power source for standalone systems.
Fdtd calculation model for the transient analyses of grounding systemsHimmelstern
This document evaluates different parameters for calculating the transient impedance of grounding systems using the finite-difference time-domain (FDTD) method. It first adjusts the derivation of transient current to obtain more accurate impedance values. It then evaluates the FDTD calculation model to determine optimized parameters that accurately predict impedance without requiring huge computational resources. Specifically, it analyzes the effects of transient voltage integration path, reference electrode length and distance, injected current type and height. It finds that integrating the transient voltage parallel to the connecting line provides the most accurate impedance results without large computational needs.
Wireless power transfer using multiple-transmitters for high stability for p...IJECEIAES
The aim of this study is to optimize the system in the wireless power supply using multiple transmitters by algebraically analyzing the effects of both a circuit parameter and an axis displacement, etc. In addition to these analyses, the other aim is designing, producing and evaluating wireless charger with high stability for position. In the proposed method, we analyzed the situation in which three transmitters are used as power sources. It is turned out that the optimum arrangement of three transmitters is equilateral triangular from Biot-Savart law and circuit equation. In the experiment, transmitted power is measured when the receiver is moved on the vertical plane in regard to central axis of coils. It is confirmed that 4~4.5mW is transmitted at the face-to-face of transmitters and 2.4mW is transmitted at the center of transmitters.
Similar to Effect of Dew and Raindrops on Electric Field around EHV Transmission Lines (20)
Amazon products reviews classification based on machine learning, deep learni...TELKOMNIKA JOURNAL
In recent times, the trend of online shopping through e-commerce stores and websites has grown to a huge extent. Whenever a product is purchased on an e-commerce platform, people leave their reviews about the product. These reviews are very helpful for the store owners and the product’s manufacturers for the betterment of their work process as well as product quality. An automated system is proposed in this work that operates on two datasets D1 and D2 obtained from Amazon. After certain preprocessing steps, N-gram and word embedding-based features are extracted using term frequency-inverse document frequency (TF-IDF), bag of words (BoW) and global vectors (GloVe), and Word2vec, respectively. Four machine learning (ML) models support vector machines (SVM), logistic regression (RF), logistic regression (LR), multinomial Naïve Bayes (MNB), two deep learning (DL) models convolutional neural network (CNN), long-short term memory (LSTM), and standalone bidirectional encoder representations (BERT) are used to classify reviews as either positive or negative. The results obtained by the standard ML, DL models and BERT are evaluated using certain performance evaluation measures. BERT turns out to be the best-performing model in the case of D1 with an accuracy of 90% on features derived by word embedding models while the CNN provides the best accuracy of 97% upon word embedding features in the case of D2. The proposed model shows better overall performance on D2 as compared to D1.
Design, simulation, and analysis of microstrip patch antenna for wireless app...TELKOMNIKA JOURNAL
In this study, a microstrip patch antenna that works at 3.6 GHz was built and tested to see how well it works. In this work, Rogers RT/Duroid 5880 has been used as the substrate material, with a dielectric permittivity of 2.2 and a thickness of 0.3451 mm; it serves as the base for the examined antenna. The computer simulation technology (CST) studio suite is utilized to show the recommended antenna design. The goal of this study was to get a more extensive transmission capacity, a lower voltage standing wave ratio (VSWR), and a lower return loss, but the main goal was to get a higher gain, directivity, and efficiency. After simulation, the return loss, gain, directivity, bandwidth, and efficiency of the supplied antenna are found to be -17.626 dB, 9.671 dBi, 9.924 dBi, 0.2 GHz, and 97.45%, respectively. Besides, the recreation uncovered that the transfer speed side-lobe level at phi was much better than those of the earlier works, at -28.8 dB, respectively. Thus, it makes a solid contender for remote innovation and more robust communication.
Design and simulation an optimal enhanced PI controller for congestion avoida...TELKOMNIKA JOURNAL
This document describes using a snake optimization algorithm to tune the gains of an enhanced proportional-integral controller for congestion avoidance in a TCP/AQM system. The controller aims to maintain a stable and desired queue size without noise or transmission problems. A linearized model of the TCP/AQM system is presented. An enhanced PI controller combining nonlinear gain and original PI gains is proposed. The snake optimization algorithm is then used to tune the parameters of the enhanced PI controller to achieve optimal system performance and response. Simulation results are discussed showing the proposed controller provides a stable and robust behavior for congestion control.
Improving the detection of intrusion in vehicular ad-hoc networks with modifi...TELKOMNIKA JOURNAL
Vehicular ad-hoc networks (VANETs) are wireless-equipped vehicles that form networks along the road. The security of this network has been a major challenge. The identity-based cryptosystem (IBC) previously used to secure the networks suffers from membership authentication security features. This paper focuses on improving the detection of intruders in VANETs with a modified identity-based cryptosystem (MIBC). The MIBC is developed using a non-singular elliptic curve with Lagrange interpolation. The public key of vehicles and roadside units on the network are derived from number plates and location identification numbers, respectively. Pseudo-identities are used to mask the real identity of users to preserve their privacy. The membership authentication mechanism ensures that only valid and authenticated members of the network are allowed to join the network. The performance of the MIBC is evaluated using intrusion detection ratio (IDR) and computation time (CT) and then validated with the existing IBC. The result obtained shows that the MIBC recorded an IDR of 99.3% against 94.3% obtained for the existing identity-based cryptosystem (EIBC) for 140 unregistered vehicles attempting to intrude on the network. The MIBC shows lower CT values of 1.17 ms against 1.70 ms for EIBC. The MIBC can be used to improve the security of VANETs.
Conceptual model of internet banking adoption with perceived risk and trust f...TELKOMNIKA JOURNAL
Understanding the primary factors of internet banking (IB) acceptance is critical for both banks and users; nevertheless, our knowledge of the role of users’ perceived risk and trust in IB adoption is limited. As a result, we develop a conceptual model by incorporating perceived risk and trust into the technology acceptance model (TAM) theory toward the IB. The proper research emphasized that the most essential component in explaining IB adoption behavior is behavioral intention to use IB adoption. TAM is helpful for figuring out how elements that affect IB adoption are connected to one another. According to previous literature on IB and the use of such technology in Iraq, one has to choose a theoretical foundation that may justify the acceptance of IB from the customer’s perspective. The conceptual model was therefore constructed using the TAM as a foundation. Furthermore, perceived risk and trust were added to the TAM dimensions as external factors. The key objective of this work was to extend the TAM to construct a conceptual model for IB adoption and to get sufficient theoretical support from the existing literature for the essential elements and their relationships in order to unearth new insights about factors responsible for IB adoption.
Efficient combined fuzzy logic and LMS algorithm for smart antennaTELKOMNIKA JOURNAL
The smart antennas are broadly used in wireless communication. The least mean square (LMS) algorithm is a procedure that is concerned in controlling the smart antenna pattern to accommodate specified requirements such as steering the beam toward the desired signal, in addition to placing the deep nulls in the direction of unwanted signals. The conventional LMS (C-LMS) has some drawbacks like slow convergence speed besides high steady state fluctuation error. To overcome these shortcomings, the present paper adopts an adaptive fuzzy control step size least mean square (FC-LMS) algorithm to adjust its step size. Computer simulation outcomes illustrate that the given model has fast convergence rate as well as low mean square error steady state.
Design and implementation of a LoRa-based system for warning of forest fireTELKOMNIKA JOURNAL
This paper presents the design and implementation of a forest fire monitoring and warning system based on long range (LoRa) technology, a novel ultra-low power consumption and long-range wireless communication technology for remote sensing applications. The proposed system includes a wireless sensor network that records environmental parameters such as temperature, humidity, wind speed, and carbon dioxide (CO2) concentration in the air, as well as taking infrared photos.The data collected at each sensor node will be transmitted to the gateway via LoRa wireless transmission. Data will be collected, processed, and uploaded to a cloud database at the gateway. An Android smartphone application that allows anyone to easily view the recorded data has been developed. When a fire is detected, the system will sound a siren and send a warning message to the responsible personnel, instructing them to take appropriate action. Experiments in Tram Chim Park, Vietnam, have been conducted to verify and evaluate the operation of the system.
Wavelet-based sensing technique in cognitive radio networkTELKOMNIKA JOURNAL
Cognitive radio is a smart radio that can change its transmitter parameter based on interaction with the environment in which it operates. The demand for frequency spectrum is growing due to a big data issue as many Internet of Things (IoT) devices are in the network. Based on previous research, most frequency spectrum was used, but some spectrums were not used, called spectrum hole. Energy detection is one of the spectrum sensing methods that has been frequently used since it is easy to use and does not require license users to have any prior signal understanding. But this technique is incapable of detecting at low signal-to-noise ratio (SNR) levels. Therefore, the wavelet-based sensing is proposed to overcome this issue and detect spectrum holes. The main objective of this work is to evaluate the performance of wavelet-based sensing and compare it with the energy detection technique. The findings show that the percentage of detection in wavelet-based sensing is 83% higher than energy detection performance. This result indicates that the wavelet-based sensing has higher precision in detection and the interference towards primary user can be decreased.
A novel compact dual-band bandstop filter with enhanced rejection bandsTELKOMNIKA JOURNAL
In this paper, we present the design of a new wide dual-band bandstop filter (DBBSF) using nonuniform transmission lines. The method used to design this filter is to replace conventional uniform transmission lines with nonuniform lines governed by a truncated Fourier series. Based on how impedances are profiled in the proposed DBBSF structure, the fractional bandwidths of the two 10 dB-down rejection bands are widened to 39.72% and 52.63%, respectively, and the physical size has been reduced compared to that of the filter with the uniform transmission lines. The results of the electromagnetic (EM) simulation support the obtained analytical response and show an improved frequency behavior.
Deep learning approach to DDoS attack with imbalanced data at the application...TELKOMNIKA JOURNAL
A distributed denial of service (DDoS) attack is where one or more computers attack or target a server computer, by flooding internet traffic to the server. As a result, the server cannot be accessed by legitimate users. A result of this attack causes enormous losses for a company because it can reduce the level of user trust, and reduce the company’s reputation to lose customers due to downtime. One of the services at the application layer that can be accessed by users is a web-based lightweight directory access protocol (LDAP) service that can provide safe and easy services to access directory applications. We used a deep learning approach to detect DDoS attacks on the CICDDoS 2019 dataset on a complex computer network at the application layer to get fast and accurate results for dealing with unbalanced data. Based on the results obtained, it is observed that DDoS attack detection using a deep learning approach on imbalanced data performs better when implemented using synthetic minority oversampling technique (SMOTE) method for binary classes. On the other hand, the proposed deep learning approach performs better for detecting DDoS attacks in multiclass when implemented using the adaptive synthetic (ADASYN) method.
The appearance of uncertainties and disturbances often effects the characteristics of either linear or nonlinear systems. Plus, the stabilization process may be deteriorated thus incurring a catastrophic effect to the system performance. As such, this manuscript addresses the concept of matching condition for the systems that are suffering from miss-match uncertainties and exogeneous disturbances. The perturbation towards the system at hand is assumed to be known and unbounded. To reach this outcome, uncertainties and their classifications are reviewed thoroughly. The structural matching condition is proposed and tabulated in the proposition 1. Two types of mathematical expressions are presented to distinguish the system with matched uncertainty and the system with miss-matched uncertainty. Lastly, two-dimensional numerical expressions are provided to practice the proposed proposition. The outcome shows that matching condition has the ability to change the system to a design-friendly model for asymptotic stabilization.
Implementation of FinFET technology based low power 4×4 Wallace tree multipli...TELKOMNIKA JOURNAL
Many systems, including digital signal processors, finite impulse response (FIR) filters, application-specific integrated circuits, and microprocessors, use multipliers. The demand for low power multipliers is gradually rising day by day in the current technological trend. In this study, we describe a 4×4 Wallace multiplier based on a carry select adder (CSA) that uses less power and has a better power delay product than existing multipliers. HSPICE tool at 16 nm technology is used to simulate the results. In comparison to the traditional CSA-based multiplier, which has a power consumption of 1.7 µW and power delay product (PDP) of 57.3 fJ, the results demonstrate that the Wallace multiplier design employing CSA with first zero finding logic (FZF) logic has the lowest power consumption of 1.4 µW and PDP of 27.5 fJ.
Evaluation of the weighted-overlap add model with massive MIMO in a 5G systemTELKOMNIKA JOURNAL
The flaw in 5G orthogonal frequency division multiplexing (OFDM) becomes apparent in high-speed situations. Because the doppler effect causes frequency shifts, the orthogonality of OFDM subcarriers is broken, lowering both their bit error rate (BER) and throughput output. As part of this research, we use a novel design that combines massive multiple input multiple output (MIMO) and weighted overlap and add (WOLA) to improve the performance of 5G systems. To determine which design is superior, throughput and BER are calculated for both the proposed design and OFDM. The results of the improved system show a massive improvement in performance ver the conventional system and significant improvements with massive MIMO, including the best throughput and BER. When compared to conventional systems, the improved system has a throughput that is around 22% higher and the best performance in terms of BER, but it still has around 25% less error than OFDM.
Reflector antenna design in different frequencies using frequency selective s...TELKOMNIKA JOURNAL
In this study, it is aimed to obtain two different asymmetric radiation patterns obtained from antennas in the shape of the cross-section of a parabolic reflector (fan blade type antennas) and antennas with cosecant-square radiation characteristics at two different frequencies from a single antenna. For this purpose, firstly, a fan blade type antenna design will be made, and then the reflective surface of this antenna will be completed to the shape of the reflective surface of the antenna with the cosecant-square radiation characteristic with the frequency selective surface designed to provide the characteristics suitable for the purpose. The frequency selective surface designed and it provides the perfect transmission as possible at 4 GHz operating frequency, while it will act as a band-quenching filter for electromagnetic waves at 5 GHz operating frequency and will be a reflective surface. Thanks to this frequency selective surface to be used as a reflective surface in the antenna, a fan blade type radiation characteristic at 4 GHz operating frequency will be obtained, while a cosecant-square radiation characteristic at 5 GHz operating frequency will be obtained.
Reagentless iron detection in water based on unclad fiber optical sensorTELKOMNIKA JOURNAL
A simple and low-cost fiber based optical sensor for iron detection is demonstrated in this paper. The sensor head consist of an unclad optical fiber with the unclad length of 1 cm and it has a straight structure. Results obtained shows a linear relationship between the output light intensity and iron concentration, illustrating the functionality of this iron optical sensor. Based on the experimental results, the sensitivity and linearity are achieved at 0.0328/ppm and 0.9824 respectively at the wavelength of 690 nm. With the same wavelength, other performance parameters are also studied. Resolution and limit of detection (LOD) are found to be 0.3049 ppm and 0.0755 ppm correspondingly. This iron sensor is advantageous in that it does not require any reagent for detection, enabling it to be simpler and cost-effective in the implementation of the iron sensing.
Impact of CuS counter electrode calcination temperature on quantum dot sensit...TELKOMNIKA JOURNAL
In place of the commercial Pt electrode used in quantum sensitized solar cells, the low-cost CuS cathode is created using electrophoresis. High resolution scanning electron microscopy and X-ray diffraction were used to analyze the structure and morphology of structural cubic samples with diameters ranging from 40 nm to 200 nm. The conversion efficiency of solar cells is significantly impacted by the calcination temperatures of cathodes at 100 °C, 120 °C, 150 °C, and 180 °C under vacuum. The fluorine doped tin oxide (FTO)/CuS cathode electrode reached a maximum efficiency of 3.89% when it was calcined at 120 °C. Compared to other temperature combinations, CuS nanoparticles crystallize at 120 °C, which lowers resistance while increasing electron lifetime.
In place of the commercial Pt electrode used in quantum sensitized solar cells, the low-cost CuS cathode is created using electrophoresis. High resolution scanning electron microscopy and X-ray diffraction were used to analyze the structure and morphology of structural cubic samples with diameters ranging from 40 nm to 200 nm. The conversion efficiency of solar cells is significantly impacted by the calcination temperatures of cathodes at 100 °C, 120 °C, 150 °C, and 180 °C under vacuum. The fluorine doped tin oxide (FTO)/CuS cathode electrode reached a maximum efficiency of 3.89% when it was calcined at 120 °C. Compared to other temperature combinations, CuS nanoparticles crystallize at 120 °C, which lowers resistance while increasing electron lifetime.
A progressive learning for structural tolerance online sequential extreme lea...TELKOMNIKA JOURNAL
This article discusses the progressive learning for structural tolerance online sequential extreme learning machine (PSTOS-ELM). PSTOS-ELM can save robust accuracy while updating the new data and the new class data on the online training situation. The robustness accuracy arises from using the householder block exact QR decomposition recursive least squares (HBQRD-RLS) of the PSTOS-ELM. This method is suitable for applications that have data streaming and often have new class data. Our experiment compares the PSTOS-ELM accuracy and accuracy robustness while data is updating with the batch-extreme learning machine (ELM) and structural tolerance online sequential extreme learning machine (STOS-ELM) that both must retrain the data in a new class data case. The experimental results show that PSTOS-ELM has accuracy and robustness comparable to ELM and STOS-ELM while also can update new class data immediately.
Electroencephalography-based brain-computer interface using neural networksTELKOMNIKA JOURNAL
This study aimed to develop a brain-computer interface that can control an electric wheelchair using electroencephalography (EEG) signals. First, we used the Mind Wave Mobile 2 device to capture raw EEG signals from the surface of the scalp. The signals were transformed into the frequency domain using fast Fourier transform (FFT) and filtered to monitor changes in attention and relaxation. Next, we performed time and frequency domain analyses to identify features for five eye gestures: opened, closed, blink per second, double blink, and lookup. The base state was the opened-eyes gesture, and we compared the features of the remaining four action gestures to the base state to identify potential gestures. We then built a multilayer neural network to classify these features into five signals that control the wheelchair’s movement. Finally, we designed an experimental wheelchair system to test the effectiveness of the proposed approach. The results demonstrate that the EEG classification was highly accurate and computationally efficient. Moreover, the average performance of the brain-controlled wheelchair system was over 75% across different individuals, which suggests the feasibility of this approach.
Adaptive segmentation algorithm based on level set model in medical imagingTELKOMNIKA JOURNAL
For image segmentation, level set models are frequently employed. It offer best solution to overcome the main limitations of deformable parametric models. However, the challenge when applying those models in medical images stills deal with removing blurs in image edges which directly affects the edge indicator function, leads to not adaptively segmenting images and causes a wrong analysis of pathologies wich prevents to conclude a correct diagnosis. To overcome such issues, an effective process is suggested by simultaneously modelling and solving systems’ two-dimensional partial differential equations (PDE). The first PDE equation allows restoration using Euler’s equation similar to an anisotropic smoothing based on a regularized Perona and Malik filter that eliminates noise while preserving edge information in accordance with detected contours in the second equation that segments the image based on the first equation solutions. This approach allows developing a new algorithm which overcome the studied model drawbacks. Results of the proposed method give clear segments that can be applied to any application. Experiments on many medical images in particular blurry images with high information losses, demonstrate that the developed approach produces superior segmentation results in terms of quantity and quality compared to other models already presented in previeous works.
Automatic channel selection using shuffled frog leaping algorithm for EEG bas...TELKOMNIKA JOURNAL
Drug addiction is a complex neurobiological disorder that necessitates comprehensive treatment of both the body and mind. It is categorized as a brain disorder due to its impact on the brain. Various methods such as electroencephalography (EEG), functional magnetic resonance imaging (FMRI), and magnetoencephalography (MEG) can capture brain activities and structures. EEG signals provide valuable insights into neurological disorders, including drug addiction. Accurate classification of drug addiction from EEG signals relies on appropriate features and channel selection. Choosing the right EEG channels is essential to reduce computational costs and mitigate the risk of overfitting associated with using all available channels. To address the challenge of optimal channel selection in addiction detection from EEG signals, this work employs the shuffled frog leaping algorithm (SFLA). SFLA facilitates the selection of appropriate channels, leading to improved accuracy. Wavelet features extracted from the selected input channel signals are then analyzed using various machine learning classifiers to detect addiction. Experimental results indicate that after selecting features from the appropriate channels, classification accuracy significantly increased across all classifiers. Particularly, the multi-layer perceptron (MLP) classifier combined with SFLA demonstrated a remarkable accuracy improvement of 15.78% while reducing time complexity.
Comparative analysis between traditional aquaponics and reconstructed aquapon...bijceesjournal
The aquaponic system of planting is a method that does not require soil usage. It is a method that only needs water, fish, lava rocks (a substitute for soil), and plants. Aquaponic systems are sustainable and environmentally friendly. Its use not only helps to plant in small spaces but also helps reduce artificial chemical use and minimizes excess water use, as aquaponics consumes 90% less water than soil-based gardening. The study applied a descriptive and experimental design to assess and compare conventional and reconstructed aquaponic methods for reproducing tomatoes. The researchers created an observation checklist to determine the significant factors of the study. The study aims to determine the significant difference between traditional aquaponics and reconstructed aquaponics systems propagating tomatoes in terms of height, weight, girth, and number of fruits. The reconstructed aquaponics system’s higher growth yield results in a much more nourished crop than the traditional aquaponics system. It is superior in its number of fruits, height, weight, and girth measurement. Moreover, the reconstructed aquaponics system is proven to eliminate all the hindrances present in the traditional aquaponics system, which are overcrowding of fish, algae growth, pest problems, contaminated water, and dead fish.
Advanced control scheme of doubly fed induction generator for wind turbine us...IJECEIAES
This paper describes a speed control device for generating electrical energy on an electricity network based on the doubly fed induction generator (DFIG) used for wind power conversion systems. At first, a double-fed induction generator model was constructed. A control law is formulated to govern the flow of energy between the stator of a DFIG and the energy network using three types of controllers: proportional integral (PI), sliding mode controller (SMC) and second order sliding mode controller (SOSMC). Their different results in terms of power reference tracking, reaction to unexpected speed fluctuations, sensitivity to perturbations, and resilience against machine parameter alterations are compared. MATLAB/Simulink was used to conduct the simulations for the preceding study. Multiple simulations have shown very satisfying results, and the investigations demonstrate the efficacy and power-enhancing capabilities of the suggested control system.
TIME DIVISION MULTIPLEXING TECHNIQUE FOR COMMUNICATION SYSTEMHODECEDSIET
Time Division Multiplexing (TDM) is a method of transmitting multiple signals over a single communication channel by dividing the signal into many segments, each having a very short duration of time. These time slots are then allocated to different data streams, allowing multiple signals to share the same transmission medium efficiently. TDM is widely used in telecommunications and data communication systems.
### How TDM Works
1. **Time Slots Allocation**: The core principle of TDM is to assign distinct time slots to each signal. During each time slot, the respective signal is transmitted, and then the process repeats cyclically. For example, if there are four signals to be transmitted, the TDM cycle will divide time into four slots, each assigned to one signal.
2. **Synchronization**: Synchronization is crucial in TDM systems to ensure that the signals are correctly aligned with their respective time slots. Both the transmitter and receiver must be synchronized to avoid any overlap or loss of data. This synchronization is typically maintained by a clock signal that ensures time slots are accurately aligned.
3. **Frame Structure**: TDM data is organized into frames, where each frame consists of a set of time slots. Each frame is repeated at regular intervals, ensuring continuous transmission of data streams. The frame structure helps in managing the data streams and maintaining the synchronization between the transmitter and receiver.
4. **Multiplexer and Demultiplexer**: At the transmitting end, a multiplexer combines multiple input signals into a single composite signal by assigning each signal to a specific time slot. At the receiving end, a demultiplexer separates the composite signal back into individual signals based on their respective time slots.
### Types of TDM
1. **Synchronous TDM**: In synchronous TDM, time slots are pre-assigned to each signal, regardless of whether the signal has data to transmit or not. This can lead to inefficiencies if some time slots remain empty due to the absence of data.
2. **Asynchronous TDM (or Statistical TDM)**: Asynchronous TDM addresses the inefficiencies of synchronous TDM by allocating time slots dynamically based on the presence of data. Time slots are assigned only when there is data to transmit, which optimizes the use of the communication channel.
### Applications of TDM
- **Telecommunications**: TDM is extensively used in telecommunication systems, such as in T1 and E1 lines, where multiple telephone calls are transmitted over a single line by assigning each call to a specific time slot.
- **Digital Audio and Video Broadcasting**: TDM is used in broadcasting systems to transmit multiple audio or video streams over a single channel, ensuring efficient use of bandwidth.
- **Computer Networks**: TDM is used in network protocols and systems to manage the transmission of data from multiple sources over a single network medium.
### Advantages of TDM
- **Efficient Use of Bandwidth**: TDM all
DEEP LEARNING FOR SMART GRID INTRUSION DETECTION: A HYBRID CNN-LSTM-BASED MODELgerogepatton
As digital technology becomes more deeply embedded in power systems, protecting the communication
networks of Smart Grids (SG) has emerged as a critical concern. Distributed Network Protocol 3 (DNP3)
represents a multi-tiered application layer protocol extensively utilized in Supervisory Control and Data
Acquisition (SCADA)-based smart grids to facilitate real-time data gathering and control functionalities.
Robust Intrusion Detection Systems (IDS) are necessary for early threat detection and mitigation because
of the interconnection of these networks, which makes them vulnerable to a variety of cyberattacks. To
solve this issue, this paper develops a hybrid Deep Learning (DL) model specifically designed for intrusion
detection in smart grids. The proposed approach is a combination of the Convolutional Neural Network
(CNN) and the Long-Short-Term Memory algorithms (LSTM). We employed a recent intrusion detection
dataset (DNP3), which focuses on unauthorized commands and Denial of Service (DoS) cyberattacks, to
train and test our model. The results of our experiments show that our CNN-LSTM method is much better
at finding smart grid intrusions than other deep learning algorithms used for classification. In addition,
our proposed approach improves accuracy, precision, recall, and F1 score, achieving a high detection
accuracy rate of 99.50%.
Introduction- e - waste – definition - sources of e-waste– hazardous substances in e-waste - effects of e-waste on environment and human health- need for e-waste management– e-waste handling rules - waste minimization techniques for managing e-waste – recycling of e-waste - disposal treatment methods of e- waste – mechanism of extraction of precious metal from leaching solution-global Scenario of E-waste – E-waste in India- case studies.
Optimizing Gradle Builds - Gradle DPE Tour Berlin 2024Sinan KOZAK
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The proper function of the integrated circuit (IC) in an inhibiting electromagnetic environment has always been a serious concern throughout the decades of revolution in the world of electronics, from disjunct devices to today’s integrated circuit technology, where billions of transistors are combined on a single chip. The automotive industry and smart vehicles in particular, are confronting design issues such as being prone to electromagnetic interference (EMI). Electronic control devices calculate incorrect outputs because of EMI and sensors give misleading values which can prove fatal in case of automotives. In this paper, the authors have non exhaustively tried to review research work concerned with the investigation of EMI in ICs and prediction of this EMI using various modelling methodologies and measurement setups.
Embedded machine learning-based road conditions and driving behavior monitoringIJECEIAES
Car accident rates have increased in recent years, resulting in losses in human lives, properties, and other financial costs. An embedded machine learning-based system is developed to address this critical issue. The system can monitor road conditions, detect driving patterns, and identify aggressive driving behaviors. The system is based on neural networks trained on a comprehensive dataset of driving events, driving styles, and road conditions. The system effectively detects potential risks and helps mitigate the frequency and impact of accidents. The primary goal is to ensure the safety of drivers and vehicles. Collecting data involved gathering information on three key road events: normal street and normal drive, speed bumps, circular yellow speed bumps, and three aggressive driving actions: sudden start, sudden stop, and sudden entry. The gathered data is processed and analyzed using a machine learning system designed for limited power and memory devices. The developed system resulted in 91.9% accuracy, 93.6% precision, and 92% recall. The achieved inference time on an Arduino Nano 33 BLE Sense with a 32-bit CPU running at 64 MHz is 34 ms and requires 2.6 kB peak RAM and 139.9 kB program flash memory, making it suitable for resource-constrained embedded systems.
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Using recycled concrete aggregates (RCA) for pavements is crucial to achieving sustainability. Implementing RCA for new pavement can minimize carbon footprint, conserve natural resources, reduce harmful emissions, and lower life cycle costs. Compared to natural aggregate (NA), RCA pavement has fewer comprehensive studies and sustainability assessments.
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International Conference on NLP, Artificial Intelligence, Machine Learning and Applications (NLAIM 2024) offers a premier global platform for exchanging insights and findings in the theory, methodology, and applications of NLP, Artificial Intelligence, Machine Learning, and their applications. The conference seeks substantial contributions across all key domains of NLP, Artificial Intelligence, Machine Learning, and their practical applications, aiming to foster both theoretical advancements and real-world implementations. With a focus on facilitating collaboration between researchers and practitioners from academia and industry, the conference serves as a nexus for sharing the latest developments in the field.
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electric field intensity, a region where the electrical breakdown can initiate [3]. The presence of
water droplets at insulator surface will increase the electrical field intensity which creates
elecrical breakdown or flashover and combination of moisture and contamination causes
flashover at operating voltage; hence, affects reliability of power delivery [4]. Another research
that has been conducted showed that the occurrence of water droplets on outdoor insulators
due to rain, fog, dew etc. leads to localized field enhancement causing partial discharges and
dry arcs which ultimately result in complete flashover [5]. The presence of water droplets over
the insulator surface enhances the electric field intensity and leads to electrical breakdown.
Water droplets/films lead to the breakdown of the insulator even under the absence of actual
contaminants. The effect of water droplets / films in causing an electrical breakdown on practical
insulator at various levels of hydrophobicity [6].
The effect of water droplets on the surface of the insulating material (i.e. silicon rubber
and porcelain) against the electric field has been researched. The result showed that E-field
intensity depended on the distance between the water droplets and the electrodes and also on
the relative distance between two water droplets and for multiple droplets the field patterns
varied with respect to the change in number, relative position, contact angle of droplets and the
location of the water droplet is more significant compared with the number of water droplets [7].
Meanwhile, these water droplets cause the electric field enhancements at the triple points
(interfacial point of three dielectric mediums i.e. solid, liquid and air) which may lead to external
partial discharge or even flashover [8].
The purpose of this research is to know the fluctuation of the voltage gradient at the
ground surface that was affected by the presence of the raindrops and dew in the space
between each phase conductor of the extra high voltage transmission lines and the ground
surface. The research subject was a 500 kV, EHV Transmission lines that are located at
Gabusan Village in Sewon Sub-District, in Bantul Regency, in Yogyakarta Special
Territory, Indonesia.
By calculation, this paper analyzed the influences of the ‘fog-dew’ and raindrops on the
electric field through modelling approach of the conductors’ configuration design of the
transmission lines, the electrostatic equation model, to determine the Maxwell Potential
Coefficient Matrix (MPCM) and finally the magnitude of voltage gradient and the exposure of the
electric field can be visualized.
2. Research Method
2.1. General View of the Extra High Voltage Transmission Lines
The extra high voltage (EHV) transmission lines have 500 kV operational voltage at the
frequency of 50 Herzt, 3-phase, vertical configuration, two-ground wires, and 6-phase
conductors with double circuit. For the purpose of analysis, the method of computation indicated
in the following is valid for the most general case, and for any kind of line configuration,
including multiple circuits. Each conductor of the transmission line, including wires at the ground
potential, must be considered. In the case of regular bundles, it is sufficient to consider their
equivalent single conductor having diameter dEq [9] given by:
√ (1)
where D is the bundle diameter; i.e. the diameter of the circle on which the subconductors lie, n
is the number of subconductors, and d is the diameter of the subconductors. The charge Q on
the conductors is determined through the voltage and the Maxwell potential coefficients P, the
equation is known as electrostatic equation in the form of matrix [9].
, - ( ) , - (2)
Both voltages and charges can be represented by complex quantities [9] and the above matrix
relationship is intended for both the real and the imaginary part
, - , - , - , - * , - , - + (3)
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where
, - , - , - , - , - , - (4)
The elements of the matrix [ P ] are given by [9]
. / ( ) (5)
where Hx is the height of the conductor x above ground, dx is the conductor diameter, Lxy is the
distance between conductor x and conductor y, and L’xy is the distance between conductor x
and the image of conductor y. The voltage gradient at ground level [9] due to each conductor
line charge is:
( ) ( )
(6)
where Qrx and Qix are the real and the imaginary parts of the charge on the conductor x, Lx is
the horizontal distance between conductor and the point on the ground at which the gradient is
computed. Therefore, the total gradient of a transmission line [9], 3-phase is given by:
∑ (7)
The llustration of the voltage gradient Gx that corresponds to equation (7) is as follow [9]:
HX
Image - Q
Q = Qrx + j Qix
GX
LX
Figure 1. Voltage gradient at ground caused by a single conductor line charge
Several models and analysis in this research are needed. There are five stages that consist of :
a. Model of the air space of a 500 kV, EHV transmisson lines
b. Model of the Composite Dielectric Constant
c. Model of Maxwell Potential Coefficient Matrix
d. Model of Electrostatic Equation
e. Calculation of Electrical Field of a 500 kV, EHV Transmission lines
2.2. Model of the air space of a 500 kV, EHV transmisson lines
The model of the transmission line was the air space with 300 meters in length, 200
meters in width, and 60 meters in height. The air space will be filled by water when it rains and
filled by pure air when it does not rain. Because the rain is the water droplets, the medium
shape of a dielectric material is the composite medium between dielectric material of the water
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droplets and the pure air. The formulation of this composite medium is given by the
permittivity c [10]:
. /
. /
(8)
The following is the sequence of modelings of extra high voltage transmission lines when the air
space is filled by water droplets:
(a)
1
200 meter
Ls = 500 meter
a2
a
a1
2
(b)
4
Ruang lapisan yang terisi udara murni
Ruang air murni
a
a1
a2
Ls
a1 = C1
a2 = C2
Permukaan Tanah
3
(c) (d)
Figure 2. Modeling of the space between phase-conductor and ground surface when dew and
raindrops are present
2.3 Model of the Composite Dielectric Constant
Figures 2c and 2d are a model of the composite delectrics between the pure air and
dew and raindrops that have been composited and have value of composite permittivity as
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shown by the equation (8). From the computer study the value of composite permittivity
between water droplets and the pure air that entered the air space as shown in Figure 2a and
the curve of the composite permittivity is shown by Figure 3 [11].
(1.1, 43)
(1.15, 69)
(1.21, 98)
Light Raindrops
until heavy rain
Dense dew
Light dew
Contentsofwaterdroplets(%)
Composite Permittivity C
Figure 3. Composite permittivity between air and dew/raindrops
2.4 Model of Maxwell Potential Coefficient Matrix (MPCM)
The Maxwell Potential Coefficient Matrix (MPCM) is shaped by equation (5) through
design data of the transmission lines that apply the concept of electric dipole to the conductors
of transmission lines that have the tower structure of vertical configuration. The following is the
form of the MPCM that is based on the configuration of an extra high voltage transmission lines
which are evaluated [11].
P11 P12 P13 P14 P15 P16 P1-G1 P1-G2
P21 P22 P23 P24 P25 P26 P2-G1 P2-G2
P31 P32 P33 P34 P35 P36 P3-G1 P3-G2
P41 P42 P43 P44 P45 P46 P4-G1 P4-G2
P51 P52 P53 P54 P55 P56 P5-G1 P5-G2
P61 P62 P63 P64 P65 P66 P6-G1 P6-G2
PG1-1 PG1-2 PG1-3 PG1-4 PG1-5 PG1-6 PG1-G1 PG1-G2
PG2-1 PG2-3 PG2-3 PG2-4 PG2-5 PG2-6 PG2-PG1 PG2-G2
Figure 4. The Maxwell Potential Coefficient Matrix (MPCM)
2.5 Model of Electrostatic Equation
The electrostatic equation of the EHV tansmission lines 500 kV, vertical configuration,
double circuit (R, S, T and U, V, W), and two ground wires (G1 and G2) are the simultaneous
linear equations (SLE) that have 8 equations with 8 variables Q (electric charge) that were not
known. The variables of Q1 until Q6 are charges in phase-conductors. Furthermore, the Q7
and Q8 are charges in the ground wire respectively. The SLE can be written as follows:
(9)
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2.6 Simulation of Electrical Field of a 500 kV, EHV Transmission lines
The simulation was conducted using equation (6) at which value of charge (Q) was
determined by inversing [P] in the equation (9). The exposure of the electric field was ploted
through variables Lx, Hx, and the charge Q in equation (6).This simulation was conducted by
computer which used Matlab. The following is the flow chart of the simulation [11]:
S t a r t
With the Matlab Finding:
1. Maxwell Potential Coeff.
2. The Electric Charge at
Phase-conductors and
Ground wires
3. Composite Permittivity
4. Ploting :
a. Exposure of Electric
Field
b. Determining Value of
Electric field intensity
Through MATLAB Finding
Yes .. !
Not Yet...!
Exposure of Electic Field
in condition:
a. Fog/ dew
b. Raindroplets
c. Fair weather
Finish
Appearing :
Instalating of Data
1. Conductor diameter
2. Height conductor
3. Distance between:
phase conductors& its
image, conductor and
conductor
Have all data
been
considered ... ?
Figure 5. Flow chart of computer for the calculation of electric field
3. Results and Discussion
3.1 The Electric Field of a 500 kV EHV Transmission Line
The exposure of the electric field is presented in the condition: fair weather with
contents of water droplets 25%, 50%, 70%, and 100% (in heavy rain condition). The exposure
of electrical field is divided into four corridors: A, B, C, and D corridors. These corridors are
located at lateral distance which is the same as at its axis: 0 m, 36 m, 62 m, and 150 m
respectively as shown in Figure 6.
ElectricField(V/m)
Lateral Distance (m)
A
A
2525
BB
C C
DD
Figure 6. The exposure of lateral electric field with distance of 200 m
The result of the research conducted by Mpanga et al showed that the lateral distance
was taken as far as 40 meters on the corridor edge with a range of electric fields fluctuating
from 10 kV / m (minimum) to 32.38 kV /m (maximum) [12]. In this research, the growth of axis
was taken as far as 200 meters to the edge of the corridor, each divided into the corridors A, B,
C, and D, i.e. as far as: 0 m, 36 m, 62 m, and 150 m at the axis.
Mpanga et al did not take into account the air condition around transmission lines which
have construction of a horizontal configuration [12], not a vertical configuration, as in the case
under investigation. The consequence is that the position of the height of the conductor will
certainly be different. Mpanga et al only expose the electric field distribution in a longitudinal
profile and mix the exposure of the voltage gradient to the conductor surface and the lateral
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electric field distribution profile on the surface of the soil [12].This study showed that the electric
field exposure curve had a good agreement.
The electric field generated by the extra high-voltage transmission line is part of a
quasi-electrostatic electric field. The result of the research conducted by Caibo et al [13] about
the influence of contamination on electric field distribution in direct current (DC) voltage dividers
showed that the intensity of the electric field along the surface path which has been subjected to
electric field magnitudes for electrostatic field types is slightly larger than the type of quasi-
electrostatic field (almost insignificant) [13]. This fact indicates that when the air around the
phase conductor is contaminated with moisture and water droplets (in humid contamination
conditions) it turns out that each corridor has a small electric field fluctuation difference as
shown Table 1, except in corridor C where the fluctuation interval is slightly larger than
corridors A, B, and D. However, if a cluster of fog of the dew or rain droplets enter the volume
space of the EHV transmission lines, the electric field intensity of transmission lines at the level
extra high voltage (EHV) can increase and decrease.
3.2 The Electric Field at the Corridors A, B, C, and D
At corridor C located 62 meters from the coordinate (0.0) as shown in Figure 6, the
magnitude of the electric field is 5.59 Volt/m. On the other hand, the electric field in the corridor
A (0 meter from the coordinate 0.0) the magnitude of the electric field will be 3,821.31 Volt/m at
condition of fair weather. Furthermore, when the air is fog of dew with contents of the water 25
%, 50 %, 70 %, and 100 % (heavy rain), the electric field at corridor ‘A’ will be 3,594.44 Volt/m,
3,374.98 Volt/m, 3,205.77 Volt/m, and 2,964.81 Volt/m respectively. Tabel 1 below showed the
change of the electric field at corridors: A, B, C, and D.
Tabel 1. The influence of the dew and raindroplets against the elecric field Intensity
Corridor
Corridor
Location
(meter)
The intensity of Electric Field (Volt/meter)
Fair
Weather
CW = 0 %
Fog of Dew
Rain droplets
CW = 100 %CW = 25
%
CW = 50
%
CW = 70
%
A 0 3,821.31 3,594.44 3,374.98 3,205.77 2,964.81
B 36 718.36 674.79 651.22 648.30 670.78
C 62 5.59 57.71 115.82 162.38 232.25
D 150 45.15 44.14 45.75 48.78 55.60
Note: CW = Contents of Water
3.3 The Change of the Electric Field at Corridors A and B
Corridor A is a location of the exposure of electric field at the coordinate (0, 0), the
electric field of which has maximum value. At this corridor the electric field decreases linearly as
shown in Figure 7 when the weather under fog of the dew at which contents of the water
droplets in the air are from 0% to 25%, 50%, 70%, and 100% (rain droplets condition).
MagnitudeoftheElectricField(Voltpermeter)
Contents of Water Droplets (%)
25 50 70 100
Corridor A
Corridor B
Corridor C 232.25
670.78
2964.81
3821.31
718.36
(25, 3594.44)
(25, 674.79)
(50, 3374.98)
(50, 651.22)
(70, 3374.98)
(70, 648.30)
Figure 7. The change of the electric field at corridor A, B and C
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Corridor B is a location of the exposure of electric field at the coordinate (36.0) which is
the magnitude of the electric field with the value of: 718.36, 674.79, 651.22, 648.30, and rises
again to 670.78 V/m. The change of the electric field is shown by Figure 7 as a parabolic curve.
The change of the electric field corresponds to contents of the water in air i.e. 0%, 25%, 50%,
70%, and 100% at the coordinate (36.0).
3.4 The Change of the Electric Field at Corridors C and D
Corridor C is a location of the exposure of electric field at the coordinate (62.0) which is
the maghnitude of the electric field with the value of: 5.59, 57.71, 115.82, 162.38, and rises
again to 232.25 V/m. The change of the electric field is shown by Figure 8 as a linear curve and
makes the rate of electric field change that corresponds to contents of the water in air space i.e
0%, 25%, 50%, 70%, and 100% at the coordinate (62.0).
Corridor D is a location of the exposure of electric field at the coordinate (150.0) which
is the maghnitude of the electric field with the value of: 45.15, 44.14, 45.75, 48.78, and then
rises to 55.60 V/m. The effect of the droplets (raindrops) and dew agaisnt the exposure of the
electric field at corridor D is shown by Figure 8 as a little part of a parabolic curve that
corresponds to contents of the water in air i.e.: 0%, 25%, 50%, 70%, and 100% respectively.
MagnitudeoftheElectricField(Voltper
meter)
Contents of Water Droplets (%)
5025 70 100
232.25
162.38
115.82
57.71
45.75
(50, 45.75)(25, 44.14)
(70, 45.75)
Corridor C
Corridor D
Figure 8. The change of the electric field at corridor C and Corridor D
4. Conclusion
Based on the analysis and description above it can be concluded that the exposure and
intensity of the electric field in several places under the extra high voltage (UHV) transmission
lines changed when dew and raindrop were present in the air space under the UHV
transmission lines. There were four locations where the changing of the intensity of the electric
field occurred due to the dew and raindrops i.e. corridors A, B, C, and D with coordinate (0.0);
(36.0); (62.0) and (150.0) respectively. The effect of the water droplets either the water of dew
or the raindrops at corridors A, B, C, and D can increase and decrease the intensity of the
electric field. The corridor A, located at the coordinat (0, 0), the electric field will decrease along
with the increase of the contents of the water. Otherwise, at corridor C, the intensity of the
electric field will increase along with the increase of the contents of the water. At corridor B, the
electric field decreased to 648.30 Volt/meter that corresponds to the contents of the water in air
70% while at corridor D, the electric field decreased to 44.14 Volt/meter with condition that the
contents of the water in air are 25%.
Acknowledgements
The research project was financed by the Directorate General of Higher Education
(DGHE or DIKTI) Republic of Indonesia No. SP DIPA-023.04.1.673453/2015, through Letter of
the DGHE No. : 0100/E5.1/PE/2015, in its appendix at the serial number: 8933.
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