International Journal of Modern Engineering Research (IJMER) is Peer reviewed, online Journal. It serves as an international archival forum of scholarly research related to engineering and science education.
Determination of Surface Currents on Circular Microstrip AntennaswailGodaymi1
This work aims to present a theoretical analysis of the electric and magnetic surface current densities of a circular
microstrip antenna (CMSA) as a body of revolution.
The rigorous analysis of these problems begins with the application of the equivalence principle, which introduces
an unknown electric current density on the conducting surface and both unknown equivalent electric and magnetic
surface current densities on the dielectric surface. These current densities satisfy the integral equations (IEs) obtained
by canceling the tangential components of the electric field on the conducting surface and enforcing the continuity
of the tangential components of the fields across the dielectric surface. The formulation of the radiation problems is
based on the combined field integral equation. This formulation is coupled with the method of moments (MoMs) as
a numerical solution for this equation.
Radiation patterns account of a circular microstrip antenna loaded two annularwailGodaymi1
In this paper, theoretical study of circular microstrip antenna loaded two annular (CMSAL2AR) and calculation
of the radiation pattern using principle equivalence with moment of method formulation of electromagnetic
radiation in this these based on the bodies of revolution (BoR), which are generated by revolution a planar curve
about an axis called axis of symmetry to solving the electric fields integral equation (EFIE) and magnetic field
integral equation (MFIE). To find an unknown electric current density on the conductor surface ,and both
unknowns electric and magnetic density current on the dielectric surface which are responsible for the
generation of far fields radiation in the space for the components (Eθ ,Eφ) ,the surface currents was represented
by a set of basis functions that give the Fourier series because the body has a circular symmetry property and
then select a set of weighted functions to find a linear system by using Galerkin method which requires that the
weighted functions are equal to the complex conjugate of the current ( ) * W = J .from radiation pattern
calculated the Directive gain can be utilized to the directive gain increased to (G= 21.30 dB) when
( 0.015λ 1 = g R ) for the ratio of (Rab= 5.5), and bandwidth has been better (BW%= 19.9%) when
( 0.01λ 1 = g R ) for the ratio (Rab= 6.5) .
Determination of Surface Currents on Circular Microstrip AntennaswailGodaymi1
This work aims to present a theoretical analysis of the electric and magnetic surface current densities of a circular
microstrip antenna (CMSA) as a body of revolution.
The rigorous analysis of these problems begins with the application of the equivalence principle, which introduces
an unknown electric current density on the conducting surface and both unknown equivalent electric and magnetic
surface current densities on the dielectric surface. These current densities satisfy the integral equations (IEs) obtained
by canceling the tangential components of the electric field on the conducting surface and enforcing the continuity
of the tangential components of the fields across the dielectric surface. The formulation of the radiation problems is
based on the combined field integral equation. This formulation is coupled with the method of moments (MoMs) as
a numerical solution for this equation.
Radiation patterns account of a circular microstrip antenna loaded two annularwailGodaymi1
In this paper, theoretical study of circular microstrip antenna loaded two annular (CMSAL2AR) and calculation
of the radiation pattern using principle equivalence with moment of method formulation of electromagnetic
radiation in this these based on the bodies of revolution (BoR), which are generated by revolution a planar curve
about an axis called axis of symmetry to solving the electric fields integral equation (EFIE) and magnetic field
integral equation (MFIE). To find an unknown electric current density on the conductor surface ,and both
unknowns electric and magnetic density current on the dielectric surface which are responsible for the
generation of far fields radiation in the space for the components (Eθ ,Eφ) ,the surface currents was represented
by a set of basis functions that give the Fourier series because the body has a circular symmetry property and
then select a set of weighted functions to find a linear system by using Galerkin method which requires that the
weighted functions are equal to the complex conjugate of the current ( ) * W = J .from radiation pattern
calculated the Directive gain can be utilized to the directive gain increased to (G= 21.30 dB) when
( 0.015λ 1 = g R ) for the ratio of (Rab= 5.5), and bandwidth has been better (BW%= 19.9%) when
( 0.01λ 1 = g R ) for the ratio (Rab= 6.5) .
NON-SPLIT PERFECTLY MATCHED LAYER BOUNDARY CONDITIONS FOR NUMERICAL SOLUTION ...ijeljournal
This paper developed a non - split perfectly matched layer (PML) boundary condition (BC) for Finite Difference Time Domain (FDTD) simulation of electromagnetic wave propagation in 2D structure. The
point source for electric field has been exploited for propagation of electromagnetic field through 2D structures to validate developed approach. The identity of resulted field distribution to that obtained for split PML BC have been demonstrated.
Non-split Perfectly Matched Layer Boundary Conditions for Numerical Solution ...ijeljournal
This paper developed a non - split perfectly matched layer (PML) boundary condition (BC) for Finite Difference Time Domain (FDTD) simulation of electromagnetic wave propagation in 2D structure. The point source for electric field has been exploited for propagation of electromagnetic field through 2D structures to validate developed approach. The identity of resulted field distribution to that obtained for split PML BC have been demonstrated.
Method of Moment analysis of a printed Archimedian Spiral antenna Piyush Kashyap
A single arm Archimedean spiral printed on a grounded dielectric substrate is analyzed using the method of moments. Piecewise sinusoidal subdomain basis and test functions are used over curved segments that exactly follow the spiral curvature. Results for the input impedance obtained using the curved segmentation approach on MATLAB are compared with those obtained after simulating the model on FEKO. A comparison with published results shows that the curved segment model requires fewer segments and is therefore significantly more computationally efficient than the linear segmentation model.
The main stake is to detect a defective component or likely to become it during manufacture or inservice inspections, while improving control productivity. In this context, we develop a simulation tool of EC fastened structures testing, integrated to the ANSYS platform, aimed at conceiving testing methods, optimizing and qualifying it. The finite element method has been chosen, it is suitable for this type of problem. Various configurations have been considered for the inspection of a target with a defect in different thicknesses. Due to the impossibility to detect a defect located at a distance much greater than the skin depth δ. Indeed, the eddy currents amplitude are less than 95% of the maximum amplitude beyond a depth greater than 3 δ. We are interested in the detection of defects located at depths higher to three times the skin depth.
Numerical simulation of electromagnetic radiation using high-order discontinu...IJECEIAES
In this paper, we propose the simulation of 2-dimensional electromagnetic wave radiation using high-order discontinuous Galerkin time domain method to solve Maxwell's equations. The domains are discretized into unstructured straight-sided triangle elements that allow enhanced flexibility when dealing with complex geometries. The electric and magnetic fields are expanded into a high-order polynomial spectral approximation over each triangle element. The field conservation between the elements is enforced using central difference flux calculation at element interfaces. Perfectly matched layer (PML) boundary condition is used to absorb the waves that leave the domain. The comparison of numerical calculations is performed by the graphical displays and numerical data of radiation phenomenon and presented particularly with the results of the FDTD method. Finally, our simulations show that the proposed method can handle simulation of electromagnetic radiation with complex geometries easily.
Electronic bands structure and gap in mid-infrared detector InAs/GaSb type II...IJERA Editor
We present here theoretical study of the electronic bands structure E (d1) of InAs (d1=25 Å)/GaSb (d2=25 Å) type
II superlattice at 4.2 K performed in the envelope function formalism. We study the effect of d1 and the offset ,
between heavy holes bands edges of InAs and GaSb, on the band gap Eg (), at the center of the first Brillouin
zone, and the semiconductor-to-semimetal transition. Eg (, T) decreases from 288.7 meV at 4.2 K to 230 meV
at 300K. In the investigated temperature range, the cut-off wavelength 4.3 m ≤ c ≤ 5.4 m situates this sample
as mid-wavelength infrared detector (MWIR). Our results are in good agreement with the experimental data
realized by C. Cervera et al.
This is a webquest about Digital Citizenship for sixth to eighth graders. It covers topics such as plagiarism and "netiquette". From this webquest, the students will create a Digital Citizenship portfolio and analyze the information to conclude what Digital Citizenship means to them.
Education set for collecting and visualizing data using sensor system based ...IJMER
This article presents the issues of the wireless sensor measuring systems design which might
be used in education process of computer science faculty. The work shows the integration of a simple
measuring system, data management system, visual system and the hardware. Education set is designed
to consolidate knowledge in many fields of computer science and the interdependence between them, as
programming techniques, database, Web server, communications protocols, software and hardware.
Presented measuring sensor system consists of a number of measurement nodes, whose role is to
provide information about certain desirable characteristics, warning against natural hazards or
violation of the physical safety. An important part of the sensor system is a measuring subsystem and
the collecting measurement data subsystem. The article presents the temperature measurement sensor
system concepts and measurement data storage and visualization methods
An Inclusive Analysis on Various Image Enhancement TechniquesIJMER
Digital Image enhancement is the process of adjusting digital images so that the results are
more suitable for display or further image analysis. It provides a multitude of choices for improving the
visual quality of images or to provide a “better transform representation for future automated image
processing. The enhancement technique differs from one field to another field. The existing techniques
of image enhancement can be classified into two categories: Spatial Domain and Frequency domain
enhancement. Many images like satellite images, medical images, aerial images and even real life
photographs suffer from poor contrast and noise. It improves the quality (clarity) of images for human
viewing by eradicating blurs, noise, increasing contrast, and revealing image details.
NON-SPLIT PERFECTLY MATCHED LAYER BOUNDARY CONDITIONS FOR NUMERICAL SOLUTION ...ijeljournal
This paper developed a non - split perfectly matched layer (PML) boundary condition (BC) for Finite Difference Time Domain (FDTD) simulation of electromagnetic wave propagation in 2D structure. The
point source for electric field has been exploited for propagation of electromagnetic field through 2D structures to validate developed approach. The identity of resulted field distribution to that obtained for split PML BC have been demonstrated.
Non-split Perfectly Matched Layer Boundary Conditions for Numerical Solution ...ijeljournal
This paper developed a non - split perfectly matched layer (PML) boundary condition (BC) for Finite Difference Time Domain (FDTD) simulation of electromagnetic wave propagation in 2D structure. The point source for electric field has been exploited for propagation of electromagnetic field through 2D structures to validate developed approach. The identity of resulted field distribution to that obtained for split PML BC have been demonstrated.
Method of Moment analysis of a printed Archimedian Spiral antenna Piyush Kashyap
A single arm Archimedean spiral printed on a grounded dielectric substrate is analyzed using the method of moments. Piecewise sinusoidal subdomain basis and test functions are used over curved segments that exactly follow the spiral curvature. Results for the input impedance obtained using the curved segmentation approach on MATLAB are compared with those obtained after simulating the model on FEKO. A comparison with published results shows that the curved segment model requires fewer segments and is therefore significantly more computationally efficient than the linear segmentation model.
The main stake is to detect a defective component or likely to become it during manufacture or inservice inspections, while improving control productivity. In this context, we develop a simulation tool of EC fastened structures testing, integrated to the ANSYS platform, aimed at conceiving testing methods, optimizing and qualifying it. The finite element method has been chosen, it is suitable for this type of problem. Various configurations have been considered for the inspection of a target with a defect in different thicknesses. Due to the impossibility to detect a defect located at a distance much greater than the skin depth δ. Indeed, the eddy currents amplitude are less than 95% of the maximum amplitude beyond a depth greater than 3 δ. We are interested in the detection of defects located at depths higher to three times the skin depth.
Numerical simulation of electromagnetic radiation using high-order discontinu...IJECEIAES
In this paper, we propose the simulation of 2-dimensional electromagnetic wave radiation using high-order discontinuous Galerkin time domain method to solve Maxwell's equations. The domains are discretized into unstructured straight-sided triangle elements that allow enhanced flexibility when dealing with complex geometries. The electric and magnetic fields are expanded into a high-order polynomial spectral approximation over each triangle element. The field conservation between the elements is enforced using central difference flux calculation at element interfaces. Perfectly matched layer (PML) boundary condition is used to absorb the waves that leave the domain. The comparison of numerical calculations is performed by the graphical displays and numerical data of radiation phenomenon and presented particularly with the results of the FDTD method. Finally, our simulations show that the proposed method can handle simulation of electromagnetic radiation with complex geometries easily.
Electronic bands structure and gap in mid-infrared detector InAs/GaSb type II...IJERA Editor
We present here theoretical study of the electronic bands structure E (d1) of InAs (d1=25 Å)/GaSb (d2=25 Å) type
II superlattice at 4.2 K performed in the envelope function formalism. We study the effect of d1 and the offset ,
between heavy holes bands edges of InAs and GaSb, on the band gap Eg (), at the center of the first Brillouin
zone, and the semiconductor-to-semimetal transition. Eg (, T) decreases from 288.7 meV at 4.2 K to 230 meV
at 300K. In the investigated temperature range, the cut-off wavelength 4.3 m ≤ c ≤ 5.4 m situates this sample
as mid-wavelength infrared detector (MWIR). Our results are in good agreement with the experimental data
realized by C. Cervera et al.
This is a webquest about Digital Citizenship for sixth to eighth graders. It covers topics such as plagiarism and "netiquette". From this webquest, the students will create a Digital Citizenship portfolio and analyze the information to conclude what Digital Citizenship means to them.
Education set for collecting and visualizing data using sensor system based ...IJMER
This article presents the issues of the wireless sensor measuring systems design which might
be used in education process of computer science faculty. The work shows the integration of a simple
measuring system, data management system, visual system and the hardware. Education set is designed
to consolidate knowledge in many fields of computer science and the interdependence between them, as
programming techniques, database, Web server, communications protocols, software and hardware.
Presented measuring sensor system consists of a number of measurement nodes, whose role is to
provide information about certain desirable characteristics, warning against natural hazards or
violation of the physical safety. An important part of the sensor system is a measuring subsystem and
the collecting measurement data subsystem. The article presents the temperature measurement sensor
system concepts and measurement data storage and visualization methods
An Inclusive Analysis on Various Image Enhancement TechniquesIJMER
Digital Image enhancement is the process of adjusting digital images so that the results are
more suitable for display or further image analysis. It provides a multitude of choices for improving the
visual quality of images or to provide a “better transform representation for future automated image
processing. The enhancement technique differs from one field to another field. The existing techniques
of image enhancement can be classified into two categories: Spatial Domain and Frequency domain
enhancement. Many images like satellite images, medical images, aerial images and even real life
photographs suffer from poor contrast and noise. It improves the quality (clarity) of images for human
viewing by eradicating blurs, noise, increasing contrast, and revealing image details.
Secure and Efficient Hierarchical Data Aggregation in Wireless Sensor NetworksIJMER
International Journal of Modern Engineering Research (IJMER) is Peer reviewed, online Journal. It serves as an international archival forum of scholarly research related to engineering and science education.
International Journal of Modern Engineering Research (IJMER) covers all the fields of engineering and science: Electrical Engineering, Mechanical Engineering, Civil Engineering, Chemical Engineering, Computer Engineering, Agricultural Engineering, Aerospace Engineering, Thermodynamics, Structural Engineering, Control Engineering, Robotics, Mechatronics, Fluid Mechanics, Nanotechnology, Simulators, Web-based Learning, Remote Laboratories, Engineering Design Methods, Education Research, Students' Satisfaction and Motivation, Global Projects, and Assessment…. And many more.
International Journal of Modern Engineering Research (IJMER) is Peer reviewed, online Journal. It serves as an international archival forum of scholarly research related to engineering and science education.
International Journal of Modern Engineering Research (IJMER) covers all the fields of engineering and science: Electrical Engineering, Mechanical Engineering, Civil Engineering, Chemical Engineering, Computer Engineering, Agricultural Engineering, Aerospace Engineering, Thermodynamics, Structural Engineering, Control Engineering, Robotics, Mechatronics, Fluid Mechanics, Nanotechnology, Simulators, Web-based Learning, Remote Laboratories, Engineering Design Methods, Education Research, Students' Satisfaction and Motivation, Global Projects, and Assessment…. And many more.
An Empirical Study on Identification of Strokes and their Significance in Scr...IJMER
International Journal of Modern Engineering Research (IJMER) is Peer reviewed, online Journal. It serves as an international archival forum of scholarly research related to engineering and science education.
International Journal of Modern Engineering Research (IJMER) covers all the fields of engineering and science: Electrical Engineering, Mechanical Engineering, Civil Engineering, Chemical Engineering, Computer Engineering, Agricultural Engineering, Aerospace Engineering, Thermodynamics, Structural Engineering, Control Engineering, Robotics, Mechatronics, Fluid Mechanics, Nanotechnology, Simulators, Web-based Learning, Remote Laboratories, Engineering Design Methods, Education Research, Students' Satisfaction and Motivation, Global Projects, and Assessment…. And many more.
Crack Detection of Ferromagnetic Materials through Non Destructive Testing Me...IJMER
The real components have so many defects in the material, which acts as a crack. In fact,
manufacturing of a component is not ideal. In manufacturing several kinds of defects are generated
like voids and inclusions. Thus, it must be check all the critical components through non-destructive
techniques (NDT) to detect the potential dangerous cracks. In Certain crucial components such as
Airplanes, Space Vehicles, Nuclear Plants, Heavy Machinery, Dams, Concrete etc., online monitoring
of defects is necessary. Concrete is different from other construction materials. Concrete can be made
from combination of different materials. Its final properties depend on its treatment at construction
site. To achieve this, sophisticated technologies are used. Ferromagnetic Composite Iron (FCI) is
used in power generating devices and DC brushless Motors. Laminations can be substituted by
Ferromagnetic Composite Iron (FCI) materials which offer a great manufacturing advantage. Non
Destructive testing (NDT) is a major part of quality control. In Non-Destructive testing (NDT)
different materials are tested for surface, volumetric and internal defects present in it. Non
Destructive testing (NDT) is also an assurance that the proposed product is good and reliable. To
apply these techniques, a certain level of skills is very necessary so that maximum amount of
information is fetched related to the proposed product during testing. This paper deals with the Non
Destructive Testing Methodology Used for crack detection in ferromagnetic materials.
A Subgraph Pattern Search over Graph DatabasesIJMER
International Journal of Modern Engineering Research (IJMER) is Peer reviewed, online Journal. It serves as an international archival forum of scholarly research related to engineering and science education.
International Journal of Modern Engineering Research (IJMER) covers all the fields of engineering and science: Electrical Engineering, Mechanical Engineering, Civil Engineering, Chemical Engineering, Computer Engineering, Agricultural Engineering, Aerospace Engineering, Thermodynamics, Structural Engineering, Control Engineering, Robotics, Mechatronics, Fluid Mechanics, Nanotechnology, Simulators, Web-based Learning, Remote Laboratories, Engineering Design Methods, Education Research, Students' Satisfaction and Motivation, Global Projects, and Assessment…. And many more.
The Influence Of Infinite Impedance Flanges On The Electromagnetic Field Of A...IJERA Editor
The problem of analysis of the electromagnetic field behaviour from the open end of the parallel-plate
waveguide with infinite impedance flanges is theoretically investigated. The case with the absence of impedance
flanges is also considered. Furthermore, we take into account particular features of the waveguide edges. The
effects of the impedance flanges and the edge features on the electromagnetic field and the radiation patterns of a
plane waveguide with flanges are demonstrated. The method of moments (MoM) technique which was used to
solve the integral equations is presented along with the numerical results.
The metal-insulator-semiconductor (MIS) capacitor is the most useful device in the study of semiconductor surfaces. Since most practical problems in the reliability and stability of all semiconductor devices are intimately related to their surface conditions, an understanding of the surface physics with the help of MIS capacitors is of great importance to device operations.
Effect of mesh grid structure in reducing hot carrier effect of nmos device s...ijcsa
This paper presents the critical effect of mesh grid that should be considered during process and device
simulation using modern TCAD tools in order to develop and optimize their accurate electrical
characteristics. Here, the computational modelling process of developing the NMOS device structure is
performed in Athena and Atlas. The effect of Mesh grid on net doping profile, n++, and LDD sheet
resistance that could link to unwanted “Hot Carrier Effect” were investigated by varying the device grid
resolution in both directions. It is found that y-grid give more profound effect in the doping concentration,
the junction depth formation and the value of threshold voltage during simulation. Optimized mesh grid is
obtained and tested for more accurate and faster simulation. Process parameter (such as oxide thicknesses
and Sheet resistance) as well as Device Parameter (such as linear gain “beta” and SPICE level 3 mobility
roll-off parameter “ Theta”) are extracted and investigated for further different applications.
This document presents the calculation of the electric field and electric potential in a coaxial cable using Maxwell's equations in the electrostatic case in an analytical and simulated manner using COMSOL Multiphysics.
Investigation on EM radiations from interconnects in integrated circuitsTELKOMNIKA JOURNAL
Characterization and estimation of interconnections behavior in integrated circuits design before the implementation phase is of paramount importance. This behavior seen as microstrip antennas gets complex as the internal signal (square or sine waves) frequencies increase. Thus, they become the preferred path for the propagation of electromagnetic disturbances. In this work we have worked out the numerical modeling of the electromagnetic interactions characterizing the electromagnetic compatibility in the microstrip transmission lines. The effect of these electromagnetic interactions in different structures topologies are studied through the analysis of the influence of the supply signals frequency and structures. The spacing between transmission line tracks and the number of tracks superposition is modeled. The evolution and variation of the scheme parameters in the frequency domain are determined. The transmission lines are considered parallel of equal spacing and superposed tracks of equal spacing and thickness. The capacitance and inductance matrices are computed and discussed. The results are found to comply with current research outcomes.
Research on Transformer Core Vibration under DC Bias Based on Multi-field Cou...inventionjournals
The Mathematical models for DC bias vibration analysis of the transformer core are developed in this paper. The model is combined into multi-physical field coupling modeling for vibration analysis of the transformer. By applying the primary voltage as excitation and under different DC bias, vibrations of the transformer core is simulated and analyzed.
NS2 installation guideline for the student to install the software . It use for student to install and download the software. The software is about the experimental of communication technology.
Effect of Piezoelectric Layer on Beam Parameters using Zigzag TheoryIDES Editor
An efficient higher order theory is presented for
static analysis of multilayered composite beams with
piezoelectric layers embedded or bonded to the surface, under
static electromechanical load. In this theory, the in-plane
displacement field is taken as a combination of a layer-wise
linear variation and a cubic variation across the thickness.
Transverse normal strains are neglected. The electric field is
also approximated as piecewise linear across the sub layers.
The displacement field is expressed in terms of only three
primary displacement variables excluding electric potential
variables by enforcing the conditions of zero transverse shear
stress at top and bottom of the beam and its continuity at layer
interfaces under general electromechanical loading. The effect
of thickness of the piezo-layer is observed for various loading
conditions. Also, the effect of beam lay-up on various
parameters is studied.
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Effect of Mobility on (I-V) Characteristics of Gaas MESFET Yayah Zakaria
We present in this paper an analytical model of the current–voltage (I-V) characteristics for submicron GaAs MESFET transistors. This model takes into account the analysis of the charge distribution in the active region and incorporate a field depended electron mobility, velocity saturation and charge
build-up in the channel. We propose in this frame work an algorithm of simulation based on mathematical expressions obtained previously. We propose a new mobility model describing the electric field-dependent. predictions of the simulator are compared with the experimental data [1] and
have been shown to be good.
Similar to Optimization of Surface Impedance for Reducing Surface Waves between Antennas (20)
A Study on Translucent Concrete Product and Its Properties by Using Optical F...IJMER
- Translucent concrete is a concrete based material with light-transferring properties,
obtained due to embedded light optical elements like Optical fibers used in concrete. Light is conducted
through the concrete from one end to the other. This results into a certain light pattern on the other
surface, depending on the fiber structure. Optical fibers transmit light so effectively that there is
virtually no loss of light conducted through the fibers. This paper deals with the modeling of such
translucent or transparent concrete blocks and panel and their usage and also the advantages it brings
in the field. The main purpose is to use sunlight as a light source to reduce the power consumption of
illumination and to use the optical fiber to sense the stress of structures and also use this concrete as an
architectural purpose of the building
Developing Cost Effective Automation for Cotton Seed DelintingIJMER
A low cost automation system for removal of lint from cottonseed is to be designed and
developed. The setup consists of stainless steel drum with stirrer in which cottonseeds having lint is mixed
with concentrated sulphuric acid. So lint will get burn. This lint free cottonseed treated with lime water to
neutralize acidic nature. After water washing this cottonseeds are used for agriculter purpose
Study & Testing Of Bio-Composite Material Based On Munja FibreIJMER
The incorporation of natural fibres such as munja fiber composites has gained
increasing applications both in many areas of Engineering and Technology. The aim of this study is to
evaluate mechanical properties such as flexural and tensile properties of reinforced epoxy composites.
This is mainly due to their applicable benefits as they are light weight and offer low cost compared to
synthetic fibre composites. Munja fibres recently have been a substitute material in many weight-critical
applications in areas such as aerospace, automotive and other high demanding industrial sectors. In
this study, natural munja fibre composites and munja/fibreglass hybrid composites were fabricated by a
combination of hand lay-up and cold-press methods. A new variety in munja fibre is the present work
the main aim of the work is to extract the neat fibre and is characterized for its flexural characteristics.
The composites are fabricated by reinforcing untreated and treated fibre and are tested for their
mechanical, properties strictly as per ASTM procedures.
Hybrid Engine (Stirling Engine + IC Engine + Electric Motor)IJMER
Hybrid engine is a combination of Stirling engine, IC engine and Electric motor. All these 3 are
connected together to a single shaft. The power source of the Stirling engine will be a Solar Panel. The aim of
this is to run the automobile using a Hybrid engine
Fabrication & Characterization of Bio Composite Materials Based On Sunnhemp F...IJMER
The present day technology demands eco-friendly developments. In this era the
composite material are playing a vital roal in different field of Engineering .The composite materials
are using as a principle materials. Nowaday the composite materials are utilizing as a important
component of engineering field .Where as the importance of the applications of composites is well
known, but thrust on the use of natural fibres in it for reinforcement has been given priority for some
times. But changing from synthetic fibres to natural fibres provides only half green-composites. A
partial green composite will be achieved if the matrix component is also eco-friendly. Keeping this in
view, a detailed literature surveyed has been carried out through various issues of the Journals
related to this field. The material systems used are sunnhemp fibres. Some epoxy and hardener has
been also added for stability and drying of the bio-composites. Various graphs and bar-charts are
super-imposed on each other for comparison among themselves and Graphs is plotted on MAT LAB
and ORIGIN 6.0 software. To determining tensile strengths, Various properties for different biocomposites
have been compared among themselves. Comparison of the behaviour of bio-composites of
this work has been also compare with other works. The bio-composites developed in this work are
likely to get applications in fall ceilings, partitions, bio-degradable packagings, automotive interiors,
sports things (e.g. rackets, nets, etc.), toys etc.
Geochemistry and Genesis of Kammatturu Iron Ores of Devagiri Formation, Sandu...IJMER
The Greenstone belts of Karnataka are enriched in BIFs in Dharwar craton, where Iron
formations are confined to the basin shelf, clearly separated from the deeper-water iron formation that
accumulated at the basin margin and flanking the marine basin. Geochemical data procured in terms of
major, trace and REE are plotted in various diagrams to interpret the genesis of BIFs. Al2O3, Fe2O3 (T),
TiO2, CaO, and SiO2 abundances and ratios show a wide variation. Ni, Co, Zr, Sc, V, Rb, Sr, U, Th,
ΣREE, La, Ce and Eu anomalies and their binary relationships indicate that wherever the terrigenous
component has increased, the concentration of elements of felsic such as Zr and Hf has gone up. Elevated
concentrations of Ni, Co and Sc are contributed by chlorite and other components characteristic of basic
volcanic debris. The data suggest that these formations were generated by chemical and clastic
sedimentary processes on a shallow shelf. During transgression, chemical precipitation took place at the
sediment-water interface, whereas at the time of regression. Iron ore formed with sedimentary structures
and textures in Kammatturu area, in a setting where the water column was oxygenated.
Experimental Investigation on Characteristic Study of the Carbon Steel C45 in...IJMER
In this paper, the mechanical characteristics of C45 medium carbon steel are investigated
under various working conditions. The main characteristic to be studied on this paper is impact toughness
of the material with different configurations and the experiment were carried out on charpy impact testing
equipment. This study reveals the ability of the material to absorb energy up to failure for various
specimen configurations under different heat treated conditions and the corresponding results were
compared with the analysis outcome
Non linear analysis of Robot Gun Support Structure using Equivalent Dynamic A...IJMER
Robot guns are being increasingly employed in automotive manufacturing to replace
risky jobs and also to increase productivity. Using a single robot for a single operation proves to be
expensive. Hence for cost optimization, multiple guns are mounted on a single robot and multiple
operations are performed. Robot Gun structure is an efficient way in which multiple welds can be done
simultaneously. However mounting several weld guns on a single structure induces a variety of
dynamic loads, especially during movement of the robot arm as it maneuvers to reach the weld
locations. The primary idea employed in this paper, is to model those dynamic loads as equivalent G
force loads in FEA. This approach will be on the conservative side, and will be saving time and
subsequently cost efficient. The approach of the paper is towards creating a standard operating
procedure when it comes to analysis of such structures, with emphasis on deploying various technical
aspects of FEA such as Non Linear Geometry, Multipoint Constraint Contact Algorithm, Multizone
meshing .
Static Analysis of Go-Kart Chassis by Analytical and Solid Works SimulationIJMER
This paper aims to do modelling, simulation and performing the static analysis of a go
kart chassis consisting of Circular beams. Modelling, simulations and analysis are performed using 3-D
modelling software i.e. Solid Works and ANSYS according to the rulebook provided by Indian Society of
New Era Engineers (ISNEE) for National Go Kart Championship (NGKC-14).The maximum deflection is
determined by performing static analysis. Computed results are then compared to analytical calculation,
where it is found that the location of maximum deflection agrees well with theoretical approximation but
varies on magnitude aspect.
In récent year various vehicle introduced in market but due to limitation in
carbon émission and BS Séries limitd speed availability vehicle in the market and causing of
environnent pollution over few year There is need to decrease dependancy on fuel vehicle.
bicycle is to be modified for optional in the future To implement new technique using change in
pedal assembly and variable speed gearbox such as planetary gear optimise speed of vehicle
with variable speed ratio.To increase the efficiency of bicycle for confortable drive and to
reduce torque appli éd on bicycle. we introduced epicyclic gear box in which transmission done
throgh Chain Drive (i.e. Sprocket )to rear wheel with help of Epicyclical gear Box to give
number of différent Speed during driving.To reduce torque requirent in the cycle with change in
the pedal mechanism
Integration of Struts & Spring & Hibernate for Enterprise ApplicationsIJMER
The proposal of this paper is to present Spring Framework which is widely used in
developing enterprise applications. Considering the current state where applications are developed using
the EJB model, Spring Framework assert that ordinary java beans(POJO) can be utilize with minimal
modifications. This modular framework can be used to develop the application faster and can reduce
complexity. This paper will highlight the design overview of Spring Framework along with its features that
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δ
ˆ
s-locally closed sets and spaces are known as
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ˆ
s-normal space and
δ
ˆ
s-connected space and
discussed some of their properties
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Today in era of software industry there is no perfect software framework available for
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Energy Audit is the systematic process for finding out the energy conservation
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An Implementation of I2C Slave Interface using Verilog HDLIJMER
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and from the Slave with proper synchronization.
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XST 14.1. This module acts as a slave for the microprocessor which can be customized for no data loss.
Discrete Model of Two Predators competing for One PreyIJMER
This paper investigates the dynamical behavior of a discrete model of one prey two
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Dev Dives: Train smarter, not harder – active learning and UiPath LLMs for do...UiPathCommunity
💥 Speed, accuracy, and scaling – discover the superpowers of GenAI in action with UiPath Document Understanding and Communications Mining™:
See how to accelerate model training and optimize model performance with active learning
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GDG Cloud Southlake #33: Boule & Rebala: Effective AppSec in SDLC using Deplo...James Anderson
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The Art of the Pitch: WordPress Relationships and SalesLaura Byrne
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Optimization of Surface Impedance for Reducing Surface Waves between Antennas
1. www.ijmer.com
International Journal of Modern Engineering Research (IJMER)
Vol. 3, Issue. 5, Sep - Oct. 2013 pp-3267-3271
ISSN: 2249-6645
Optimization of Surface Impedance for Reducing
Surface Waves between Antennas
Jean-François D. Essiben1, Eric R. Hedin2, and Yong S. Joe2
1
Department of Electrical Engineering, Advanced Teachers’ Training College for Technical Education University of Douala,
B. P. 1872, Douala, Cameroon
2
Center for Computational Nanoscience, Department of Physics and Astronomy Ball State University, Muncie, IN 47306,
USA
ABSTRACT: Electromagnetic coupling between two aperture antennas in the shape of the open ends of parallel-plate waveguides located on the same metal surface has been analyzed. The design optimization of the surface impedance model is
used to solve this problem. The required level of antenna decoupling is obtained taking into account the initial metal surface,
which is a natural decoupling structure. The search method is applied to determine a minimum value of the antennacoupling coefficient. The method of moments (MoM) technique has been used to solve the integral equations. Numerical solutions for optimized surface impedance distributions and antenna decouplings are presented.
Keywords: Aperture Antennas, Coupling, Method of Moments, Surface Impedance.
I. INTRODUCTION
Nonplanar antennas with radiating apertures find frequent use in radio electronics. These antennas have several advantages compared to traditional antennas with plane apertures. One of these advantages is the possibility of placing such
antennas directly on surfaces with a complex shape. Another important advantage is the fact that antennas with nonplanar
apertures allow the realization of a wider class of geometries than antennas with planar apertures.
High saturation of modern systems of radio electronics necessitates creating the placement of antennas of different
usage in direct proximity relative to other antennas. As a result, these antennas can produce interference with each other.
With the aim of reducing this harmful form of mutual influence, various measures are used to increase the decoupling between the antennas. One of the most effective measures, as shown in Refs. [1-3] for the case of surface plane location of antennas, is the use of corrugated structures. The corresponding electrodynamic model has been considered [1, 2, 4], where the
problem of coupling of two antennas located on a plane in the presence of an intervening corrugated structure is solved explicitly. The results obtained from this model can be used as an initial proposition or approximation [4].
The main purpose of this paper is the optimization problem of surface impedance for decreasing antenna-coupling
coefficients, in the case where the antennas have a common location. The history of this problem is addressed in Refs. [5-7],
where the antenna coupling coefficients are defined for different dispositions of antennas on a mobile board. Although the
problem of the definition of a minimum value of the antenna-coupling coefficient is not mentioned in these papers, the problem of minimization of the antenna-coupling coefficients for the radio board and electronic systems has been solved using
the search method [8]. The minimum value of the antenna-coupling coefficient is defined with the help of the Gauss-Zeidel
optimization method [9, 10].
In Section II of this paper, а solution to the problem of the reduction in coupling between two waveguide antennas
located on a surface impedance is given. A solution to the design optimization problem of the surface impedance for reducing coupling between antennas is obtained in section III. In section IV, the numerical simulation results are presented. Finally, conclusions are drawn in Section IV.
II. ANALYTICAL FORMULATION
We consider the problem of coupling between two waveguide antennas as shown in Figure 1a. The two aperture antennas in the shape of the open ends of parallel-plate waveguides (transmitting and receiving) with opening sizes of a and
b are located on the y 0 plane, separated by a distance L . On the surface S , the impedance boundary conditions of Shukin-Leontovich are fulfilled:
n E Zn (n H ),
(1)
where n is the normal unit to the y 0 plane, Z is the surface impedance, and E and H are the electric and magnetic
fields, respectively.
www.ijmer.com
3267 | Page
2. www.ijmer.com
International Journal of Modern Engineering Research (IJMER)
Vol. 3, Issue. 5, Sep - Oct. 2013 pp-2719-2727
ISSN: 2249-6645
(a)
(b)
Figure 1. (a) Geometry of the problem. (b) Geometry of the design problem. The magnetic current J m.ex. is located at the
height h .
It is necessary to determine the electromagnetic field (EMF) in the following regions: the upper half-space ( y 0 ,
region V1 ), the radiating waveguide ( y 0 and 0 x a , region V2 ), and the receiving waveguide ( y 0 and
a L x a L b , region V3 ). The minimum level of coupling between the two antennas can then be determined using
the surface impedance plane synthesized below. Notice that the required EMF should satisfy boundary conditions on the
flange, namely the requirement of infinite tangential components in the openings, and the standard conditions of Maxwell’s
equations for radiation.
For the solution of the general structure studied in our calculations and sketched schematically in Figure 1a, we use
the Lorentz lemma in the integral form and obtain integral correlations for each of the regions, V1 , V2 and V3 , respectively
[1, 2]. We consider the boundary conditions on the surfaces of the impedance flanges, and the equality of the tangential field
components in the openings of the waveguides ( Hz1 Hz2 , Ex1 Ex 2 in x0, a ; Hz1 Hz3 , E x1 E x3 in
x a L, a L b ), where the subscript numbers refer to the regions V1 , V2 and V3 . With regards to the specifics of the
electric field at the edges, x 0, a, a L, a L b , the solution will consist in solving the system of integral equations,
subject to the boundary conditions, for the unknown tangential component of the electric field on the surface S
( x [L1, a L b L2 ] and y 0 ) as shown in detail in Refs. [1, 2]. The solution of this equation is conveniently solved
with the use of the Krylov–Bogolyubov method [11], which gives an iterative approximation for the required value. After
obtaining the system of integral equations relative to the electric field E x ( x ) on the y 0 plane, we propose the use of the
periodic structure designed below in order to solve the given problem of coupling between the antennas.
III. DESIGN OPTIMIZATION OF THE SURFACE IMPEDANCE PLANE
In this section, we consider a solution to the two-dimensional design problem for the arrangement shown in Figure
1b. Above the plane S y 0 , there is an infinite thread of in-phase magnetic current J m.ex. located at height h . On the
surface S , the boundary impedance conditions of Shukin-Leontovich are fulfilled by Eq. (1). It is necessary to determine the
dependence of the passive impedance Zx (Re(Z) 0) on the surface S . Once Zx is obtained, the complete field in the
upper space is found, and then the degree of decoupling between antennas can be obtained.
www.ijmer.com
3268 | Page
3. International Journal of Modern Engineering Research (IJMER)
www.ijmer.com
Vol. 3, Issue. 5, Sep - Oct. 2013 pp-2719-2727
ISSN: 2249-6645
It is well known that surface impedance, comprising a mathematical model of a corrugated structure, can be used
systematically to control the radiation, scattering and propagation characteristics of the waves and, thereby, can be used to
design better antennas. Furthermore, the effective solution to the problem of reducing the coupling of airborne antennas requires the solution of the structural design problem. The design of such a two-dimensional structure is obtained in Ref. [12],
which investigates the design problem of the impedance surface when an infinite thread of in-phase magnetic current is located above the plane at a certain height. The designed impedance structure has the following form:
Z iW cos r tan
2
,
(2)
where i is the imaginary unit, W 120 ohms is the characteristic resistance of a free space and r is the angle of reflection. k(R i x cos 0 ) is a dimensionless quantity, k 2 is the wave number, R i h 2 x 2 , h is the height, and
the coordinate x gives the position of the subsidiary source. The derived impedance variation can be used as an independent
solution of the problem of providing electromagnetic compatibility, as well as the first step in further optimization of the
structure with the help of non-linear programming methods.
IV. NUMERICAL RESULTS
The solution for the designed impedance distribution is given as
(3)
Z ( x) i tan k h 2 x 2 x cos0 ,
in which the two free parameters h and 0 are included [12]. These parameters can be used for an optimization of the impedance, Zx , yielding a minimal coefficient of coupling (maximum decoupling) between the antennas.
In Figure 2, we show a graph of the variation of the impedance distribution, which provides the best decoupling for
the parameters, h 0.5 and 0 54 . The optimized impedance also gives a nearly hyperbolic reactance. The vertical solid lines represent the geometry of the problem.
Figure 2. Variation of the optimized surface impedance for the parameters: h 0.5 and
0 54 . The vertical solid lines
represent the geometry of the problem.
Figure 3 shows the dependence (red solid curve) of the decoupling coefficient K on the parameter 0 for the fixed
value h 0.5 , for a structure with length L and a b 0.34 . The blue dashed curve corresponds to the ideal conducting structure. As seen, the optimum in this case occurs for the angle of 54 . It can be stated that decoupling of antennas
does not depend sensitively on the angle 0 . This parameter alters K by not more than 10 dB.
K (), dB
Im pedance
Ordinary metal
, degrees
Figure 3. Dependence of the decoupling coefficient K on the parameter 0 for the fixed value h 0.5 . The optimal decoupling in this case is when the angle equal to 54 . L and a b 0.34 .
www.ijmer.com
3269 | Page
4. International Journal of Modern Engineering Research (IJMER)
www.ijmer.com
Vol. 3, Issue. 5, Sep - Oct. 2013 pp-2719-2727
ISSN: 2249-6645
In Figure 4, the dependence of the decoupling coefficient K on the parameter h for the fixed angle 0 54 is
shown for the same structure (red solid curve). As in the previous graph, the blue dashed curve corresponds to the ideal conducting structure. As shown here, the best decoupling of K 40 dB is obtained for the parameter h 0.5 ~ 0.6 . Further
numerical research shows that alteration of the height h leads to a shift of the maximum reactance from the opening of one
antenna to the other. This, in turn, leads to periodic alteration of the decoupling coefficient between antennas. Increasing the
length of the structure leads to the appearance of an additional maximum in the variation of the impedance distribution.
K (h), dB
Im pedance
Ordinary metal
h
Figure 4. Dependence of the decoupling coefficient K on the parameter h for the fixed angle 0 54 . The best decoupling is obtained for the parameter h 0.5 ~ 0.6 . The parameters for our calculation are the same as in the previous case.
Figure 5 shows the dependence (red solid curve) of the decoupling coefficient K for the fixed angle 0 45 , for
a structure with the parameters, L 2 and a b 0.34 . The impedance distributions for h 0.5 and h 1.8 , which
give the maximum values of decoupling, are also presented in Figures 6 (a) and 6 (b), respectively. Here, it is also possible
(with L 2 ) to consider the parameter h 0.5 as optimum. Compared to the reactance of Figure 6 (a), the reactance of
Figure 6 (b) shows a shift of x 0.5 in the values of the sharp transitions. Additionally, the reactance of the Figure 6 (a)
shows a half parabola between the points x and x 2.3 .
The impedance distributions considered above have a reactance following the functional form of tangent or cotangent over
the region x= 0 ~ :
Z ( x) iZ 0 tan(qkx) or Z ( x) iZ 0 cot(qkx) .
(4)
K (h), dB
Im pedance
Ordinary metal
h
Figure 5. Dependence of the decoupling coefficient K on the parameter h over a wide range for a fixed angle 0 45 .
Parameters used are a b 0.34 and L 2 .
Figure 6. Variations of impedance distribution for (а) h 0.5 and (b) h 1.8 . In both cases, the parameters used are
a b 0.34 , 0 45 , and L 2 .
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5. International Journal of Modern Engineering Research (IJMER)
www.ijmer.com
Vol. 3, Issue. 5, Sep - Oct. 2013 pp-2719-2727
ISSN: 2249-6645
Figure 7 (a) shows (red solid curve) the dependence of the decoupling coefficient of the two antennas
a b 0.34 , separated by the impedance structure with length L , using the form of the impedance Z i tan(qkx)
with the dimensionless parameter q . Analogous results (red solid curve) are shown in Figure 7(b) for the structure with the
impedance Z i cot(qkx) . The reactance with the functional form of the tangent gives larger local minima, reaching –43
dB. The reactance with the functional form of the cotangent gives smaller local minima but has a smoother dependence on
the parameter q . As shown, the decoupling coefficient for the cotangent case becomes K 30 ~ 40 dB, reached when
q 0.4 ~ 2 . This means that if such a structure is calculated with a coefficient q 0.4 on the lower frequency of the range, it
will give a decoupling of K 30 ~ 40 dB over the frequency range of interest. From the viewpoint of frequency properties, such a structure is preferable. We observe that in Figures 5, 7(a) and 7(b), the blue dashed curve also corresponds to the
decoupling level for the case of an ideal conducting structure.
(a )
(b )
Im pedance
Ordinary metal
K (q), dB
K (q), dB
Im pedance
Ordinary metal
q
q
Figure 7. Dependence of the decoupling coefficient K on the parameter q for the impedances (а)
Z i tan(qkx) and (b)
Z i cot(qkx) . Parameters used are a b 0.34 and L .
IV. CONCLUSION
We have solved the optimization problem of the surface impedance for reducing surface waves between antennas
located on a common plane surface. The optimized surface impedance is an inhomogeneous impedance plane designed by a
fixed reflected field. In the optimization results, we have obtained a reactance close to the functional form of tangent or cotangent, which can provide significant decoupling over a large range of frequencies.
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