In this paper, with the aim of developing a nondestructive evaluation technique using piezoelectric signals in
wooden materials, we theoretically study the electroelastic field in a semi-infinite body with D∞ symmetry
subjected to surface friction parallel to the ∞-fold rotation axis. By applying the analytical technique previously
proposed by us, we formulate expressions for electroelastic field quantities, including electric potential, electric
field, electric displacement, elastic displacement, strain, and stress by using two “elastic displacement potential
functions” and two “piezoelastic displacement potential functions.” These potential functions and, consequently,
the electroelastic field quantities are formulated using Fourier transforms in order to satisfy electroelastic
boundary conditions. We carried out numerical calculations to correctly evaluate field quantities inside the body
and at its surface. As a result, we were successful in quantitatively elucidating the surface electric displacement
in response to the elastic stimulus of surface friction and suggested the possibility of a nondestructive evaluation
technique using piezoelectric signals.
Vibrational Behaviour of Composite Beams Based on Fiber Orientation with Piez...IJMERJOURNAL
ABSTRACT: A smart structure can sense the vibration and generate a controlled actuation, so that the vibration can be minimized. For this purpose, smart materials are used as actuators and sensors. Among all the smart materials Lead Zirconate Titanate (PZT) is used as smart material and the smart structures are taken as carbon-epoxy cantilever beams. In the present work an attempt has been made to study the effect of dimensions of PZT and position of PZT on the natural frequency of smart structure. In this work the simulation analysis and experimental analysis were carried out on the carbon epoxy cantilever beams for different fibre orientations like 00 ,300 and 600 with and without PZT patch at different positions. The simulation is carried out by using ANSYS and experimentation is carried out by using FFT analyser, accelerometer and impact hammer. Both the experimentation and simulation results show the effective control in the vibration of the structure, the required decrease in the natural frequency is observed with reference to the both patch dimension and position. Thus the results of this work conclude that the dimensions of the PZTand positioning of the PZT influences the natural frequency of the smart structure.
Hysteresis Loops for Magnetoelectric Multiferroics Using Landau-Khalatnikov T...IJECEIAES
We present a theoretical discussion of the hysteresis in magnetoelectric multiferroics with bi-quadratic magnetoelectric coupling. The calculations were performed by employing Landau-Khalatnikov equation of motion for both the ferroelectric and ferromagnetic phase, then solve it simultaneously. In magnetoelectric, we obtain four types of hysteresis: ferroelectric hysteresis, ferromagnetic hysteresis and two types of cross hysteresis (electric field versus magnetization and magnetic field versus electric polarization). The cross hysteresis has butterfly shape which agree with the result from the previous research. It can also be seen from that hysteresis, that magnetization / electric polarization can not be flipped into the opposite direction using external electric / magnetic field when the magnetoelectric coupling is bi-quadratic type. Overall, the result shows that LandauKhalatnikov equation is able to approximate hysteresis loops in multiferroics system.
Galerkin’s indirect variational method in elastic stability analysis of all e...eSAT Publishing House
1. The document describes using Galerkin's indirect variational method (Galerkin's method) to analyze the buckling of thin rectangular plates with all edges clamped.
2. Galerkin's method involves approximating the solution to differential equations using a polynomial involving characteristic orthogonal polynomials.
3. The authors formulated shape functions using characteristic orthogonal polynomials and applied them in Galerkin's method to analyze buckling loads. Their results were close to those of previous research using different methods.
Transient Numerical Analysis of Induction Heating of Graphite Cruciable at Di...ijeljournal
Mathematical modeling of Induction heating process is done by using 2D axisymmetric geometry.
Induction heating is coupled field problem that includes electromagnetism and heat transfer. Mathematical
modeling of electromagnetism and heat transfer is done by using maxwell equations and classical heat
transfer equation respectively. Temperature dependent material properties are used for this analysis. This
analysis includes coil voltage distribution, crucible electromagnetic power, and coil equivalent impedance
at different frequency. Induction coil geometry effect on supply voltage is also analyzed. This analysis is
useful for designing of induction coil for melting of nonferrous metal such as gold, silver, uranium etc.
Transient numerical analysis of induction heating of graphite cruciable at di...ijeljournal
This document summarizes a numerical analysis of induction heating of a graphite crucible at different frequencies. It includes the following key points:
1. A 2D axisymmetric finite element model was developed to simulate the coupled electromagnetic and thermal behavior during induction heating. Temperature dependent material properties were considered.
2. Results showed that magnetic field penetration decreased at higher frequencies. Crucible temperature increased faster at higher frequencies due to better coupling.
3. Voltage distribution in the induction coil turns showed higher losses in the center turns due to proximity effects. This helps with coil cooling design.
4. Electromagnetic power induced in the crucible initially decreased then increased due to the unique temperature dependent conductivity of graphite
Transient Numerical Analysis of Induction Heating of Graphite Cruciable at Di...ijeljournal
Mathematical modeling of Induction heating process is done by using 2D axisymmetric geometry.
Induction heating is coupled field problem that includes electromagnetism and heat transfer. Mathematical
modeling of electromagnetism and heat transfer is done by using maxwell equations and classical heat
transfer equation respectively. Temperature dependent material properties are used for this analysis. This
analysis includes coil voltage distribution, crucible electromagnetic power, and coil equivalent impedance
at different frequency. Induction coil geometry effect on supply voltage is also analyzed. This analysis is
useful for designing of induction coil for melting of nonferrous metal such as gold, silver, uranium etc.
Analytical, Numerical and Experimental Validation of Coil Voltage in Inductio...ijeljournal
This paper presents, mathematical model of induction heating process by using analytical and numerical methods. In analytical method, series equivalent circuit (SEC) is used to represent induction coil and work piece. Induction coil and workpiece parameters (resistance and reactance) are calculated by standard formulas along with Nagaoka correction factors and Bessel functions. In Numerical method, magnetic vector potential formulation is done and finite element method (FEM) is used to solve the field equations. Analytically and numerically computed parameters such as equivalent coil resistance, reactance, coil voltage, work piece power are compared and found that they are in good agreement. Analytically and numerically obtained coil voltages at different frequencies are validated by experimental results. This mathematical model is useful for coil design and optimization of induction heating process.
Analytical, Numerical and Experimental Validation of Coil Voltage in Inductio...ijeljournal
This paper presents, mathematical model of induction heating process by using analytical and numerical methods. In analytical method, series equivalent circuit (SEC) is used to represent induction coil and work piece. Induction coil and workpiece parameters (resistance and reactance) are calculated by standard formulas along with Nagaoka correction factors and Bessel functions. In Numerical method, magnetic vector potential formulation is done and finite element method (FEM) is used to solve the field equations. Analytically and numerically computed parameters such as equivalent coil resistance, reactance, coil voltage, work piece power are compared and found that they are in good agreement. Analytically and numerically obtained coil voltages at different frequencies are validated by experimental results. This mathematical model is useful for coil design and optimization of induction heating process.
Vibrational Behaviour of Composite Beams Based on Fiber Orientation with Piez...IJMERJOURNAL
ABSTRACT: A smart structure can sense the vibration and generate a controlled actuation, so that the vibration can be minimized. For this purpose, smart materials are used as actuators and sensors. Among all the smart materials Lead Zirconate Titanate (PZT) is used as smart material and the smart structures are taken as carbon-epoxy cantilever beams. In the present work an attempt has been made to study the effect of dimensions of PZT and position of PZT on the natural frequency of smart structure. In this work the simulation analysis and experimental analysis were carried out on the carbon epoxy cantilever beams for different fibre orientations like 00 ,300 and 600 with and without PZT patch at different positions. The simulation is carried out by using ANSYS and experimentation is carried out by using FFT analyser, accelerometer and impact hammer. Both the experimentation and simulation results show the effective control in the vibration of the structure, the required decrease in the natural frequency is observed with reference to the both patch dimension and position. Thus the results of this work conclude that the dimensions of the PZTand positioning of the PZT influences the natural frequency of the smart structure.
Hysteresis Loops for Magnetoelectric Multiferroics Using Landau-Khalatnikov T...IJECEIAES
We present a theoretical discussion of the hysteresis in magnetoelectric multiferroics with bi-quadratic magnetoelectric coupling. The calculations were performed by employing Landau-Khalatnikov equation of motion for both the ferroelectric and ferromagnetic phase, then solve it simultaneously. In magnetoelectric, we obtain four types of hysteresis: ferroelectric hysteresis, ferromagnetic hysteresis and two types of cross hysteresis (electric field versus magnetization and magnetic field versus electric polarization). The cross hysteresis has butterfly shape which agree with the result from the previous research. It can also be seen from that hysteresis, that magnetization / electric polarization can not be flipped into the opposite direction using external electric / magnetic field when the magnetoelectric coupling is bi-quadratic type. Overall, the result shows that LandauKhalatnikov equation is able to approximate hysteresis loops in multiferroics system.
Galerkin’s indirect variational method in elastic stability analysis of all e...eSAT Publishing House
1. The document describes using Galerkin's indirect variational method (Galerkin's method) to analyze the buckling of thin rectangular plates with all edges clamped.
2. Galerkin's method involves approximating the solution to differential equations using a polynomial involving characteristic orthogonal polynomials.
3. The authors formulated shape functions using characteristic orthogonal polynomials and applied them in Galerkin's method to analyze buckling loads. Their results were close to those of previous research using different methods.
Transient Numerical Analysis of Induction Heating of Graphite Cruciable at Di...ijeljournal
Mathematical modeling of Induction heating process is done by using 2D axisymmetric geometry.
Induction heating is coupled field problem that includes electromagnetism and heat transfer. Mathematical
modeling of electromagnetism and heat transfer is done by using maxwell equations and classical heat
transfer equation respectively. Temperature dependent material properties are used for this analysis. This
analysis includes coil voltage distribution, crucible electromagnetic power, and coil equivalent impedance
at different frequency. Induction coil geometry effect on supply voltage is also analyzed. This analysis is
useful for designing of induction coil for melting of nonferrous metal such as gold, silver, uranium etc.
Transient numerical analysis of induction heating of graphite cruciable at di...ijeljournal
This document summarizes a numerical analysis of induction heating of a graphite crucible at different frequencies. It includes the following key points:
1. A 2D axisymmetric finite element model was developed to simulate the coupled electromagnetic and thermal behavior during induction heating. Temperature dependent material properties were considered.
2. Results showed that magnetic field penetration decreased at higher frequencies. Crucible temperature increased faster at higher frequencies due to better coupling.
3. Voltage distribution in the induction coil turns showed higher losses in the center turns due to proximity effects. This helps with coil cooling design.
4. Electromagnetic power induced in the crucible initially decreased then increased due to the unique temperature dependent conductivity of graphite
Transient Numerical Analysis of Induction Heating of Graphite Cruciable at Di...ijeljournal
Mathematical modeling of Induction heating process is done by using 2D axisymmetric geometry.
Induction heating is coupled field problem that includes electromagnetism and heat transfer. Mathematical
modeling of electromagnetism and heat transfer is done by using maxwell equations and classical heat
transfer equation respectively. Temperature dependent material properties are used for this analysis. This
analysis includes coil voltage distribution, crucible electromagnetic power, and coil equivalent impedance
at different frequency. Induction coil geometry effect on supply voltage is also analyzed. This analysis is
useful for designing of induction coil for melting of nonferrous metal such as gold, silver, uranium etc.
Analytical, Numerical and Experimental Validation of Coil Voltage in Inductio...ijeljournal
This paper presents, mathematical model of induction heating process by using analytical and numerical methods. In analytical method, series equivalent circuit (SEC) is used to represent induction coil and work piece. Induction coil and workpiece parameters (resistance and reactance) are calculated by standard formulas along with Nagaoka correction factors and Bessel functions. In Numerical method, magnetic vector potential formulation is done and finite element method (FEM) is used to solve the field equations. Analytically and numerically computed parameters such as equivalent coil resistance, reactance, coil voltage, work piece power are compared and found that they are in good agreement. Analytically and numerically obtained coil voltages at different frequencies are validated by experimental results. This mathematical model is useful for coil design and optimization of induction heating process.
Analytical, Numerical and Experimental Validation of Coil Voltage in Inductio...ijeljournal
This paper presents, mathematical model of induction heating process by using analytical and numerical methods. In analytical method, series equivalent circuit (SEC) is used to represent induction coil and work piece. Induction coil and workpiece parameters (resistance and reactance) are calculated by standard formulas along with Nagaoka correction factors and Bessel functions. In Numerical method, magnetic vector potential formulation is done and finite element method (FEM) is used to solve the field equations. Analytically and numerically computed parameters such as equivalent coil resistance, reactance, coil voltage, work piece power are compared and found that they are in good agreement. Analytically and numerically obtained coil voltages at different frequencies are validated by experimental results. This mathematical model is useful for coil design and optimization of induction heating process.
Characteristic orthogonal polynimial application to galerkin indirect variati...eSAT Publishing House
This document discusses using characteristic orthogonal polynomials (COPs) with the Galerkin method to analyze buckling of thin rectangular plates with simply supported edges under in-plane loading. COPs are generated using the Gram-Schmidt process and employed as displacement functions. The governing partial differential equation is solved using the Galerkin method by approximating the solution as a linear combination of COPs. The results are compared to previous research and show good agreement, validating that COPs provide an accurate approximation when used with the Galerkin method for buckling analysis of plates.
Analytical, Numerical and Experimental Validation of Coil Voltage in Inductio...ijeljournal
This paper presents, mathematical model of induction heating process by using analytical and numerical
methods. In analytical method, series equivalent circuit (SEC) is used to represent induction coil and work
piece. Induction coil and workpiece parameters (resistance and reactance) are calculated by standard
formulas along with Nagaoka correction factors and Bessel functions. In Numerical method, magnetic
vector potential formulation is done and finite element method (FEM) is used to solve the field equations.
Analytically and numerically computed parameters such as equivalent coil resistance, reactance, coil
voltage, work piece power are compared and found that they are in good agreement. Analytically and
numerically obtained coil voltages at different frequencies are validated by experimental results. This
mathematical model is useful for coil design and optimization of induction heating process.
Analytical, Numerical and Experimental Validation of Coil Voltage in Inductio...ijujournal
This document presents an analytical, numerical, and experimental validation of coil voltage in an induction melting process. It describes mathematical models using analytical and numerical methods to represent the induction coil and workpiece. The analytical method uses a series equivalent circuit to calculate coil and workpiece parameters. The numerical method uses finite element analysis and magnetic vector potential formulation to solve field equations. Analytically and numerically computed coil voltages are compared and found to be in good agreement. Experimental results also validate the computed coil voltages at different frequencies. The mathematical models provide a useful tool for coil design and optimization of induction heating processes.
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
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.
A chaotic particle swarm optimization (cpso) algorithm for solving optimal re...Alexander Decker
This document presents a chaotic particle swarm optimization (CPSO) algorithm for solving the multi-objective reactive power dispatch problem. The CPSO algorithm aims to avoid premature convergence by fusing ergodic and stochastic chaos. It formulates reactive power dispatch as an optimization problem with two objectives: minimizing real power losses and maximizing static voltage stability margin. The CPSO is tested on the IEEE 30 bus system and is shown to reduce power losses and maximize voltage stability more than other algorithms.
A N APPROACH TO MODEL OPTIMIZATION OF MA N- UFACTURING OF EMI T TER - COUPLE...ijcsitcejournal
In this paper we consider an approach to optimiz
e
manufacturing elements of emitter
-
coupled logic. The
optimization
leads
to decreas
ing
dimensions of these elements.
Framework this pa
per we consider man
u-
facturing
these
elements of emitter
-
coupled logic
framework
a heterostructure with required configur
a
tion
.
After grown the heterostructure
the
required areas
have been doped
by diffusion or ion implant
a
tion
.
It is
attracted an interest
optimization of annealing of dopant and/or radiation defects
to decrease dimensions
of the considered elements
.
We co
n
sider
an approach
to make the optimization.
The modeling part based
on modified method of functional corrections, which
gives us possibili
ty to analyzed manufacturing the
elements of emitter
-
coupled logic
without crosslinking of solutions on interfaces between layers of heter
o-
stru
c
ture
Static and Dynamic Reanalysis of Tapered BeamIJERA Editor
Beams are one of the common types of structural components and they are fundamentally categorized as
uniform and non-uniform beams. The non-uniform beams has the benefit of better distribution of strength and
mass than uniform beam. And non-uniform beams can meet exceptional functional needs in
aeronautics,robotics,architecture and other unconventional engineering applications. Designing of these
structures is necessary to resist dynamic forces such as earthquakes and wind.
The present paper focuses on static and dynamic reanalysis of a tapered cantilever beam structure using
multipolynomial regression method. The method deals with the characteristics of frequency of a vibrating
system and the procedures that are available for the modification of physical parameters of vibrating system.
The method is applied on a tapered cantilever beam for approximate structural static and dynamic reanalysis.
Results obtained from the assumed conditions of the problem indicate the high quality approximation of stresses
and natural frequencies using ANSYS and Regression method.
Measuring Plastic Properties from Sharp Nanoindentation: A Finite-Element Stu...CrimsonPublishersRDMS
Measuring Plastic Properties from Sharp Nanoindentation: A Finite-Element Study on the Uniqueness of Inverse Solutions by Fabian Pöhl* in Crimson Publishers: Peer Reviewed Material Science Journals
This paper studies nonlinear constitutive equations for gravitoelectromagnetism. Eventually, the problem is solved of finding, for a given particular solution of the gravity-Maxwell equations, the exact form of the corresponding nonlinear constitutive equations.
Analytical Solution Of Schrödinger Equation With Mie–Type Potential Using Fac...ijrap
we have obtained the analytical solution of Schrödinger wave equation with Mie – type potential
using factorization method. We have also obtained energy eigenvalues of our potential and the
corresponding wave function using an ansatz and then compare the result to standard Laguerre’s
differential equation. Under special cases our potential model reduces two well known potentials such as
Coulomb and the Kratzer Feus potentials.
Derivation of Maxwell's Equation for Diffusion Current and Klein-Gordon Equat...iosrjce
IOSR Journal of Applied Physics (IOSR-JAP) is a double blind peer reviewed International Journal that provides rapid publication (within a month) of articles in all areas of physics and its applications. The journal welcomes publications of high quality papers on theoretical developments and practical applications in applied physics. Original research papers, state-of-the-art reviews, and high quality technical notes are invited for publications.
Dynamic Homogenisation of randomly irregular viscoelastic metamaterialsUniversity of Glasgow
An analytical framework is developed for investigating the effect of viscoelasticity on irregular hexagonal lattices. At room temperature, many polymers are found to be near their glass temperature. Elastic moduli of honeycombs made of such materials are not constant, but changes in the time or frequency domain. Thus consideration of viscoelastic properties is essential for such honeycombs. Irregularity in lattice structures being inevitable from a practical point of view, analysis of the compound effect considering both irregularity and viscoelasticity is crucial for such structural forms. On the basis of a mechanics-based bottom-up approach, computationally efficient closed-form formulae are derived in the frequency domain. The spatially correlated structural and material attributes are obtained based on Karhunen-Lo\`{e}ve expansion, which is integrated with the developed analytical approach to quantify the viscoelastic effect for irregular lattices. Consideration of such spatially correlated behaviour can simulate the practical stochastic system more closely. Two Young's moduli and shear modulus are found to be dependent on the viscoelastic parameters, while the two in-plane Poisson's ratios are found to be independent of viscoelastic parameters. Results are presented in both deterministic and stochastic regime, wherein it is observed that the elastic moduli are significantly amplified in the frequency domain. The response bounds are quantified considering two different forms of irregularity, randomly inhomogeneous irregularity and randomly homogeneous irregularity. The computationally efficient analytical approach presented in this study can be quite attractive for practical purposes to analyse and design lattices with predominantly viscoelastic behaviour along with consideration of structural and material irregularity.
The peer-reviewed International Journal of Engineering Inventions (IJEI) is started with a mission to encourage contribution to research in Science and Technology. Encourage and motivate researchers in challenging areas of Sciences and Technology.
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) .
ON OPTIMIZATION OF MANUFACTURING OF AN AMPLIFIER TO INCREASE DENSITY OF BIPOL...ijoejournal
In this paper we consider a possibility to increase density of bipolar heterotransistor framework an amplifier
due to decreasing of their dimensions. The considered approach based on doping of required areas of
heterostructure with specific configuration by diffusion or ion implantation. The doping finished by optimized
annealing of dopant and/or radiation defects. Analysis of redistribution of dopant with account redistribution
of radiation defects (after implantation of ions of dopant) for optimization of the above annealing
have been done by using recently introduced analytical approach. The approach gives a possibility
to analyze mass and heat transports in a heterostructure without crosslinking of solutions on interfaces
between layers of the heterostructure with account nonlinearity of these transports and variation in time of
their parameters.
This document describes a study that uses finite element modeling to analyze heat transfer and thermal stresses in a circular plate due to radiation. The study solves the heat conduction equation using finite element methods to determine transient temperature distributions in the plate. Boundary conditions include radiation on the upper surface, a constant temperature on the lower surface, and insulation on the circular edge. Results for temperature, displacement, and thermal stresses in the plate are determined numerically and graphically. The finite element model provides more accurate solutions than previous analytical methods for problems with complex geometries and boundary conditions.
Bandwidth Improvement of UWB Microstrip Antenna Using Finite Ground PlaneIJERA Editor
Microstrip antennas play a vital role in communication system. It is required in high performance wireless applications. But due to its resonant nature microstrip antennas have some considerable drawbacks like narrowband performance. Extensive study has been carried out on microstrip patch antennas in the recent past, but it still have large scope for improvement in the near future. To overcome narrow bandwidth problem, number of methods and techniques have been suggested and investigated, keeping in mind that the basic advantages of microstrip antenna should not be altered such as low profile, light weight, low cost and simple printed circuit structure. The area of investigation includes modification in geometrical shape of the antenna, use of resonators, use of dipole, and many other parameters. This paper presents a comparison between conventional microstrip antenna and microstip antenna with finite ground plane at ultra wideband. HFSS simulation tool is used here for antenna simulation. For feeding purpose microstrip feed line is used (50Ω). Optimized result provides impedance bandwidth of 7.2GHz with VSWR<2, operating frequency range is from 6.5GHz to 13.7GHz. Proposed antenna is useful for many ultra wideband applications. =
This document summarizes a research paper on improving the performance of multimodal biometrics using cryptosystems. The paper proposes fusing iris and fingerprint biometrics at the feature level before applying encryption for enhanced security. It discusses extracting features from iris and fingerprint images, fusing the features, and then encrypting the fused template. This approach aims to improve accuracy over unimodal biometrics while enhancing security through encryption. The paper reviews related work on multimodal biometrics and cryptosystems, and presents results showing the proposed approach effectively extracts features and fuses the biometrics for identification.
The Information Communication and Technology industry is made up of enterprises concerned with the design, manufacture, installation, development, support and management of computer-based information systems (both software and hardware). The rapid expansion of electronic technologies within the global TELECOM industry has been accompanied by an explosion of automation applications that are redefining the way we perceive and experience communication, entertainment and security in our personal and professional environments. Convenience is now a function of the extent to which electronic appliances and gadgets are „online‟ and accessible through land and wireless networks. Information flow is expected on demand -constant, reliable, accurate and accessible. Such changes have understandably raised expectations with regards to the how effectively we function, in the places we live and work. No where have the effects of this new technology been felt as powerfully as in the global real estate industry.
Measuring innovation in the "Process" approach: the case of agro-food product...IJERA Editor
Today, innovation is an important pillar to effectively position in global markets. Nevertheless, produce a good completely new or significantly improved, requires reducing the gap between the intended purpose and the end result it either internally or externally of the firm. This paper also proposes a measurement model based on the "process" approach. This proposal is based on a set of explanatory variables and explained linking internal and external effectiveness of innovative product.
Characteristic orthogonal polynimial application to galerkin indirect variati...eSAT Publishing House
This document discusses using characteristic orthogonal polynomials (COPs) with the Galerkin method to analyze buckling of thin rectangular plates with simply supported edges under in-plane loading. COPs are generated using the Gram-Schmidt process and employed as displacement functions. The governing partial differential equation is solved using the Galerkin method by approximating the solution as a linear combination of COPs. The results are compared to previous research and show good agreement, validating that COPs provide an accurate approximation when used with the Galerkin method for buckling analysis of plates.
Analytical, Numerical and Experimental Validation of Coil Voltage in Inductio...ijeljournal
This paper presents, mathematical model of induction heating process by using analytical and numerical
methods. In analytical method, series equivalent circuit (SEC) is used to represent induction coil and work
piece. Induction coil and workpiece parameters (resistance and reactance) are calculated by standard
formulas along with Nagaoka correction factors and Bessel functions. In Numerical method, magnetic
vector potential formulation is done and finite element method (FEM) is used to solve the field equations.
Analytically and numerically computed parameters such as equivalent coil resistance, reactance, coil
voltage, work piece power are compared and found that they are in good agreement. Analytically and
numerically obtained coil voltages at different frequencies are validated by experimental results. This
mathematical model is useful for coil design and optimization of induction heating process.
Analytical, Numerical and Experimental Validation of Coil Voltage in Inductio...ijujournal
This document presents an analytical, numerical, and experimental validation of coil voltage in an induction melting process. It describes mathematical models using analytical and numerical methods to represent the induction coil and workpiece. The analytical method uses a series equivalent circuit to calculate coil and workpiece parameters. The numerical method uses finite element analysis and magnetic vector potential formulation to solve field equations. Analytically and numerically computed coil voltages are compared and found to be in good agreement. Experimental results also validate the computed coil voltages at different frequencies. The mathematical models provide a useful tool for coil design and optimization of induction heating processes.
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
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.
A chaotic particle swarm optimization (cpso) algorithm for solving optimal re...Alexander Decker
This document presents a chaotic particle swarm optimization (CPSO) algorithm for solving the multi-objective reactive power dispatch problem. The CPSO algorithm aims to avoid premature convergence by fusing ergodic and stochastic chaos. It formulates reactive power dispatch as an optimization problem with two objectives: minimizing real power losses and maximizing static voltage stability margin. The CPSO is tested on the IEEE 30 bus system and is shown to reduce power losses and maximize voltage stability more than other algorithms.
A N APPROACH TO MODEL OPTIMIZATION OF MA N- UFACTURING OF EMI T TER - COUPLE...ijcsitcejournal
In this paper we consider an approach to optimiz
e
manufacturing elements of emitter
-
coupled logic. The
optimization
leads
to decreas
ing
dimensions of these elements.
Framework this pa
per we consider man
u-
facturing
these
elements of emitter
-
coupled logic
framework
a heterostructure with required configur
a
tion
.
After grown the heterostructure
the
required areas
have been doped
by diffusion or ion implant
a
tion
.
It is
attracted an interest
optimization of annealing of dopant and/or radiation defects
to decrease dimensions
of the considered elements
.
We co
n
sider
an approach
to make the optimization.
The modeling part based
on modified method of functional corrections, which
gives us possibili
ty to analyzed manufacturing the
elements of emitter
-
coupled logic
without crosslinking of solutions on interfaces between layers of heter
o-
stru
c
ture
Static and Dynamic Reanalysis of Tapered BeamIJERA Editor
Beams are one of the common types of structural components and they are fundamentally categorized as
uniform and non-uniform beams. The non-uniform beams has the benefit of better distribution of strength and
mass than uniform beam. And non-uniform beams can meet exceptional functional needs in
aeronautics,robotics,architecture and other unconventional engineering applications. Designing of these
structures is necessary to resist dynamic forces such as earthquakes and wind.
The present paper focuses on static and dynamic reanalysis of a tapered cantilever beam structure using
multipolynomial regression method. The method deals with the characteristics of frequency of a vibrating
system and the procedures that are available for the modification of physical parameters of vibrating system.
The method is applied on a tapered cantilever beam for approximate structural static and dynamic reanalysis.
Results obtained from the assumed conditions of the problem indicate the high quality approximation of stresses
and natural frequencies using ANSYS and Regression method.
Measuring Plastic Properties from Sharp Nanoindentation: A Finite-Element Stu...CrimsonPublishersRDMS
Measuring Plastic Properties from Sharp Nanoindentation: A Finite-Element Study on the Uniqueness of Inverse Solutions by Fabian Pöhl* in Crimson Publishers: Peer Reviewed Material Science Journals
This paper studies nonlinear constitutive equations for gravitoelectromagnetism. Eventually, the problem is solved of finding, for a given particular solution of the gravity-Maxwell equations, the exact form of the corresponding nonlinear constitutive equations.
Analytical Solution Of Schrödinger Equation With Mie–Type Potential Using Fac...ijrap
we have obtained the analytical solution of Schrödinger wave equation with Mie – type potential
using factorization method. We have also obtained energy eigenvalues of our potential and the
corresponding wave function using an ansatz and then compare the result to standard Laguerre’s
differential equation. Under special cases our potential model reduces two well known potentials such as
Coulomb and the Kratzer Feus potentials.
Derivation of Maxwell's Equation for Diffusion Current and Klein-Gordon Equat...iosrjce
IOSR Journal of Applied Physics (IOSR-JAP) is a double blind peer reviewed International Journal that provides rapid publication (within a month) of articles in all areas of physics and its applications. The journal welcomes publications of high quality papers on theoretical developments and practical applications in applied physics. Original research papers, state-of-the-art reviews, and high quality technical notes are invited for publications.
Dynamic Homogenisation of randomly irregular viscoelastic metamaterialsUniversity of Glasgow
An analytical framework is developed for investigating the effect of viscoelasticity on irregular hexagonal lattices. At room temperature, many polymers are found to be near their glass temperature. Elastic moduli of honeycombs made of such materials are not constant, but changes in the time or frequency domain. Thus consideration of viscoelastic properties is essential for such honeycombs. Irregularity in lattice structures being inevitable from a practical point of view, analysis of the compound effect considering both irregularity and viscoelasticity is crucial for such structural forms. On the basis of a mechanics-based bottom-up approach, computationally efficient closed-form formulae are derived in the frequency domain. The spatially correlated structural and material attributes are obtained based on Karhunen-Lo\`{e}ve expansion, which is integrated with the developed analytical approach to quantify the viscoelastic effect for irregular lattices. Consideration of such spatially correlated behaviour can simulate the practical stochastic system more closely. Two Young's moduli and shear modulus are found to be dependent on the viscoelastic parameters, while the two in-plane Poisson's ratios are found to be independent of viscoelastic parameters. Results are presented in both deterministic and stochastic regime, wherein it is observed that the elastic moduli are significantly amplified in the frequency domain. The response bounds are quantified considering two different forms of irregularity, randomly inhomogeneous irregularity and randomly homogeneous irregularity. The computationally efficient analytical approach presented in this study can be quite attractive for practical purposes to analyse and design lattices with predominantly viscoelastic behaviour along with consideration of structural and material irregularity.
The peer-reviewed International Journal of Engineering Inventions (IJEI) is started with a mission to encourage contribution to research in Science and Technology. Encourage and motivate researchers in challenging areas of Sciences and Technology.
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) .
ON OPTIMIZATION OF MANUFACTURING OF AN AMPLIFIER TO INCREASE DENSITY OF BIPOL...ijoejournal
In this paper we consider a possibility to increase density of bipolar heterotransistor framework an amplifier
due to decreasing of their dimensions. The considered approach based on doping of required areas of
heterostructure with specific configuration by diffusion or ion implantation. The doping finished by optimized
annealing of dopant and/or radiation defects. Analysis of redistribution of dopant with account redistribution
of radiation defects (after implantation of ions of dopant) for optimization of the above annealing
have been done by using recently introduced analytical approach. The approach gives a possibility
to analyze mass and heat transports in a heterostructure without crosslinking of solutions on interfaces
between layers of the heterostructure with account nonlinearity of these transports and variation in time of
their parameters.
This document describes a study that uses finite element modeling to analyze heat transfer and thermal stresses in a circular plate due to radiation. The study solves the heat conduction equation using finite element methods to determine transient temperature distributions in the plate. Boundary conditions include radiation on the upper surface, a constant temperature on the lower surface, and insulation on the circular edge. Results for temperature, displacement, and thermal stresses in the plate are determined numerically and graphically. The finite element model provides more accurate solutions than previous analytical methods for problems with complex geometries and boundary conditions.
Bandwidth Improvement of UWB Microstrip Antenna Using Finite Ground PlaneIJERA Editor
Microstrip antennas play a vital role in communication system. It is required in high performance wireless applications. But due to its resonant nature microstrip antennas have some considerable drawbacks like narrowband performance. Extensive study has been carried out on microstrip patch antennas in the recent past, but it still have large scope for improvement in the near future. To overcome narrow bandwidth problem, number of methods and techniques have been suggested and investigated, keeping in mind that the basic advantages of microstrip antenna should not be altered such as low profile, light weight, low cost and simple printed circuit structure. The area of investigation includes modification in geometrical shape of the antenna, use of resonators, use of dipole, and many other parameters. This paper presents a comparison between conventional microstrip antenna and microstip antenna with finite ground plane at ultra wideband. HFSS simulation tool is used here for antenna simulation. For feeding purpose microstrip feed line is used (50Ω). Optimized result provides impedance bandwidth of 7.2GHz with VSWR<2, operating frequency range is from 6.5GHz to 13.7GHz. Proposed antenna is useful for many ultra wideband applications. =
This document summarizes a research paper on improving the performance of multimodal biometrics using cryptosystems. The paper proposes fusing iris and fingerprint biometrics at the feature level before applying encryption for enhanced security. It discusses extracting features from iris and fingerprint images, fusing the features, and then encrypting the fused template. This approach aims to improve accuracy over unimodal biometrics while enhancing security through encryption. The paper reviews related work on multimodal biometrics and cryptosystems, and presents results showing the proposed approach effectively extracts features and fuses the biometrics for identification.
The Information Communication and Technology industry is made up of enterprises concerned with the design, manufacture, installation, development, support and management of computer-based information systems (both software and hardware). The rapid expansion of electronic technologies within the global TELECOM industry has been accompanied by an explosion of automation applications that are redefining the way we perceive and experience communication, entertainment and security in our personal and professional environments. Convenience is now a function of the extent to which electronic appliances and gadgets are „online‟ and accessible through land and wireless networks. Information flow is expected on demand -constant, reliable, accurate and accessible. Such changes have understandably raised expectations with regards to the how effectively we function, in the places we live and work. No where have the effects of this new technology been felt as powerfully as in the global real estate industry.
Measuring innovation in the "Process" approach: the case of agro-food product...IJERA Editor
Today, innovation is an important pillar to effectively position in global markets. Nevertheless, produce a good completely new or significantly improved, requires reducing the gap between the intended purpose and the end result it either internally or externally of the firm. This paper also proposes a measurement model based on the "process" approach. This proposal is based on a set of explanatory variables and explained linking internal and external effectiveness of innovative product.
Determination of homogenous regions in the Tensift basin (Morocco).IJERA Editor
The aim of this study is to determine homogenous region in the Tensift basin within which the hydrological behavior is similar. In order to do this we used two methods: The Principal components analysis on the monthly precipitation registered at the 23 rainfall stations. This resulted in setting apart 4 groups of stations. The second method is analysis of land use map, geological map, pedagogical map, vegetation map and slope map of the studied area. This method allowed us to delineate 4 homogenous areas. The two methods yielded complementary results and the superposition of groups and regions obtained allowed us to retain 4 homogenous regions corresponding to 3 groups of stations.
The study of the basic mechanical properties of polyvinyl alcohol fiber cemen...IJERA Editor
As a new material in the construction field,polyvinyl alcohol fiber cement stabilized macadam pavement has a
very broad application prospects. The study of the basic mechanical properties of polyvinyl alcohol fiber cement
stabilized macadam is also a hot spot today. This paper studies the flexural strength of polyvinyl alcohol fiber
content is at 0.9Kg / m3,and the affect between the splitting tensile strength and the polyvinyl alcohol fiber.
This document provides information about the Parramasala festival happening in Parramatta, NSW from October 4-7, 2013. It will feature performances from international and Australian artists representing various cultures. Highlights include performances by Raghu Dixit, Fearless Nadia, Aakash Odedra Company, and a concert featuring Bollywood star Shahrukh Khan. The festival will also include parades, markets, food stalls, and family entertainment at Prince Alfred Park.
La depresión postparto afecta al 20% de las mujeres y se presenta principalmente dentro de los 3 primeros meses después del parto. Los factores de riesgo incluyen antecedentes familiares de depresión, embarazos no deseados o complicados, y falta de apoyo. Los síntomas incluyen tristeza, ansiedad, cambios de apetito y sueño. El tratamiento efectivo involucra medicamentos, terapia o ambos. Con atención médica adecuada, los síntomas generalmente desaparecen.
Premiera PricePanorama.com @ Shopcamp (14.06.2013)Grupa Manubia
Prezentacja z premiery systemu PricePanorama.com - narzędzia do monitorowania cen wszystkich produktów w internecie.
Prezentacja odbyła się 14 czerwca 2013 w Krakowie podczas kolejnej edycji spotkania "Shopcamp". Dane w prezentacji aktualne na dzień 13.06.2013.
O documento apresenta um plano de aula para o conto "O Primeiro Beijo", de Antonio Barreto. O plano inclui informações sobre o autor, o público-alvo, objetivos, atividades propostas e referências bibliográficas. As atividades envolvem a leitura do conto com perguntas, discussão de vocabulário desconhecido e intertextualidade com outras obras.
Materi Tentang Bakteriologi_Bagi Mahasiswa Keperawatanyohanes meor
Bakteri (dari kata Latin bacterium; jamak: bacteria) adalah kelompok organisme yang tidak memiliki membran inti sel. Organisme ini termasuk ke dalam domain prokariota dan berukuran sangat kecil (mikroskopik), serta memiliki peran besar dalam kehidupan di bumi. Beberapa kelompok bakteri dikenal sebagai agen penyebab infeksi dan penyakit, sedangkan kelompok lainnya dapat memberikan manfaat dibidang pangan, pengobatan, dan industri. Struktur sel bakteri relatif sederhana: tanpa nukleus/inti sel, kerangka sel, dan organel-organel lain seperti mitokondria dan kloroplas. Hal inilah yang menjadi dasar perbedaan antara sel prokariot dengan sel eukariot yang lebih kompleks.
Reliability and Fuzzy Logic Concepts as Applied to Slope Stability Analysis –...IJERA Editor
Considerable uncertainty exist with regard to stability of slopes due to several factors and recognition of these uncertainties has made designees to introduce factor of safety. Several studies, during recent years on analytical methods using soil properties have improved understanding the several uncertainties. The reliability analysis of slopes can be used to represent uncertainty in mathematical models, which can be assumed to follow the characteristic of random uncertainty. The distribution uncertain variable, which is unknown, makes its estimation difficult. Hence, the concepts of fuzzy set theory appear to be quite reliable when limited information is available. This paper attempts to review the slope stability problem and deals with the intricacies of the concept of reliability and fuzzy logic as applied to stability analysis of slope. It has been suggested that the FOSM algorithm provides a general agreement among the different slope stability solutions.
Distribution and Mobility of Heavy Metal Materials in Settling Ponds Post Lat...IJERA Editor
This document summarizes a study on the distribution and mobility of heavy metals in settling ponds after laterite nickel mining in North Motui Konawe, Southeast Sulawesi, Indonesia. The study found that:
1) The distributions of iron and chromium in the settling ponds strengthened constantly over time, indicating similar mobility and ability to form chemical compounds. Nickel and cobalt showed relatively flat distributions, suggesting similar low mobility.
2) Iron and chromium were most concentrated in sediments, forming ferrochrome compounds, while nickel had very low mobility and cobalt had even lower mobility.
3) Principal component analysis confirmed nickel had the greatest influence on the underlying ultramafic rocks, followed by iron then cobalt, and chromium
This document provides contact information for Matt Swain, a creative marketing consultant. It lists Matt Swain's name, website www.bringtheswain.com, phone number 540.336.3981 and email mswain@bringtheswain.com. It also includes a link to his LinkedIn profile at www.linkedin.com/in/mswain.
Design And Implementation Of Tiny Encryption AlgorithmIJERA Editor
Over the recent years, several smart applications like RFID‟s, sensor networks, including industrial systems, critical infrastructures, private and public spaces as well as portable and wearable applications in which highly constrained devices are interconnected, typically communicating wirelessly with one another, working in concert to accomplish some task. Advanced safety and security mechanisms can be very important in all of these areas. Light weight cryptography enables secure and efficient communication between networked smart objects. This proposed system focuses on the FPGA implementation of light weight cryptographic algorithm Tiny Encryption Algorithm TEA to adapt with many real time constraints such as memory, data loss and low cost. The proposed scheme uses Linear Feedback Shift Register to generate the random key making it more secure for sensitive information transfer in many real-time applications. In this study,operation of this cryptosystem is analyzed by implementing the cryptographic algorithm TEA with the key generation unit in FPGA Spartan 3E. We have also compared the results with the IDEA.
Qcl 14-v3 [poor placement of students]-[banasthali_university]_[rajani_ranjan]Rajani Ranjan
The document outlines the main causes of poor student placement as college factors like improper syllabus sequencing and lack of support, personal factors such as poor communication skills and low confidence, and being from a disadvantaged social group. It recommends avoiding reservation seats, enhancing student skills and personality, improving the education system, and making changes to the college selection process to overcome the root causes of poor placement. Students should also enhance themselves, manage their time well, and learn from the start.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
On the Vibration Characteristicsof Electrostatically Actuated Micro\nanoReson...IJERDJOURNAL
Electrostatic actuation is one of the most prevalent methods of excitation and measurement in micron to Nano scale resonators. Heretofore, in the dynamical behavior analyses of these systems, the resonating beam has been assumed to be perfect conductor which is obviously an approximation. In this paper, effect of electrical resistivity on the vibrational response of these systems including natural frequency and damping, is investigated. The governing coupled nonlinear partial differential equations of motion are extracted and a finite element formulationby developinga new electromechanical element is presented. Calculated natural frequencies are compared with experimental measurements and a closer agreement is achieved in comparison with previousfindings. Results indicate there is a jump in frequency and damping of the system at a critical resistivity. As system size is decreased and applied voltage approaches toward pull-in voltage, electrical resistivity fully dominates the response nature of the system.
Getting Electric Power For Piezoelectricitytheijes
This work presents the design and the implementation of a floor tile piezoelectric to obtain electric power and to feed a system of low power. To obtain the electric power across the floor tile, it is necessary to know the phenomenon called the piezoelectric effect, which is used as way that produces the electric power to a material ceramic call PZT-4 that operates as a generator, which produces the electric power for the application of mechanical energy to the material, that is to say, on having deformed the material piezoelectric for the mechanical action this one generates electric power.
TRANSIENT ANALYSIS OF PIEZOLAMINATED COMPOSITE PLATES USING HSDTP singh
Piezoelectric materials have excellent sensing and actuating capabilities have made them the most practical smart materials to integrate with laminated structures. Integrated structure system can be called a smart structure because of its ability to perform self-diagnosis and quick adaption to environment changes. An analytical procedure has been developed in the work based on higher order shear deformation theory subjected to electromechanical loading for investigating transient characteristics of smart material plates. For analysis two displacement models are to be considered i.e., model-1 accounts for strain in thickness direction is zero whereas in model-2 in-plane displacements are expanded as cubic functions of the thickness coordinate. Navier’s technique has been adopted for obtaining solutions of anti-symmetric cross–ply and angle-ply laminates of both model-1 and model-2 with simply supported boundary conditions. For obtaining transient response of a laminated composite plate attached with piezoelectric layer Newmark’s method has been used. Effect of thickness coordinate of composite laminated plates attached with piezoelectric layer subjected to electromechanical loadings is studied.
IJCER (www.ijceronline.com) International Journal of computational Engineerin...ijceronline
This document summarizes an article that presents an analytical model for the electromechanical dynamics of a simply-supported micro-plate subjected to electrostatic excitation. The model derives equations of motion for the plate and uses Galerkin's method to obtain closed-form solutions for static deflection and natural frequencies. The effect of applied voltage, gap height, and plate dimensions on natural frequencies is illustrated. A reduced-order model is also developed and compared to the distributed parameter model.
International Journal of Computational Engineering Research(IJCER)ijceronline
International Journal of Computational Engineering Research(IJCER) is an intentional online Journal in English monthly publishing journal. This Journal publish original research work that contributes significantly to further the scientific knowledge in engineering and Technology.
Analysis of the equations of discrete electron–wave interaction and electron ...Victor Solntsev
This document discusses approaches to calculating the electromagnetic field excited by an electron beam in microwave vacuum devices. It analyzes the equations of discrete interaction between an electron beam and the electromagnetic field of periodic and pseudoperiodic slow-wave structures (SWSs). The analysis is based on the difference theory of excitation of SWSs and allows for a unified description of interaction in both the passbands and rejection bands of the structures. Comparison of electron bunching processes in the linear field of a periodic SWS versus a pseudoperiodic SWS confirms the selective properties of pseudoperiodic SWSs.
Analysis of Hysteresis and Eddy Current losses in ferromagnetic plate induced...IRJET Journal
This document analyzes hysteresis and eddy current losses in a ferromagnetic plate induced by a time-varying electromagnetic field. It establishes a three-dimensional mathematical model to determine the magnetic field intensity, temperature, and stresses inside the plate. The model considers the heat generated from both eddy currents induced in the plate from the changing magnetic field, as well as hysteresis losses from the time lag of magnetization and demagnetization of the ferromagnetic material. Governing equations are derived and solved using integral transforms to illustrate the influence of various parameters on the magnetic, thermal, and elastic fields within the plate.
This document analyzes the admittance characteristics of an H-plane tee junction formed by coupling two rectangular waveguides of different bands through an inclined slot in the narrow wall. The analysis uses concepts of self-reaction and discontinuity in modal current to determine the admittance loading, coupling, and voltage standing wave ratio as functions of slot width, length, and inclination angle. Results are compared to practical measurements. Previous work analyzing longitudinal and transverse slots is discussed, but no prior literature examines an inclined slot between waveguides of different bands.
The document summarizes research investigating the influence of infinite impedance flanges on the electromagnetic field of a plane waveguide. It presents the theoretical background, describing the problem of analyzing the EM field behavior from the open end of a parallel-plate waveguide. It then details the solution approach using integral equations and the method of moments technique. Numerical results are presented demonstrating the effects of impedance flanges and edge features on the EM field and radiation patterns.
The document summarizes research investigating the influence of infinite impedance flanges on the electromagnetic field of a plane waveguide. It presents the theoretical background, describing the problem setup and boundary conditions considered. It then outlines the solution method used, which involves formulating integral equations for the unknown tangential electric field component on the waveguide surface. Numerical results are presented analyzing the effects of impedance flanges and edge features on the electromagnetic field and radiation patterns. The method of moments technique is used to solve the integral equations.
The document summarizes research investigating the influence of infinite impedance flanges on the electromagnetic field of a plane waveguide. It presents the theoretical background, describing the problem of analyzing the EM field behavior from the open end of a parallel-plate waveguide with and without impedance flanges. It also accounts for edge features of the waveguide. The method of moments technique is used to solve integral equations and obtain numerical results demonstrating the effects of impedance flanges and edges on the EM field and radiation patterns.
The Influence Of Infinite Impedance Flanges On The Electromagnetic Field Of A...IJERA Editor
The document summarizes research investigating the influence of infinite impedance flanges on the electromagnetic field of a plane waveguide. It presents the theoretical background, describing the problem setup and boundary conditions considered. It then outlines the solution method, detailing the integral equations derived to relate the unknown tangential electric field on the waveguide surface. Numerical results are presented analyzing the effects of impedance flanges and edge features on the electromagnetic field and radiation patterns.
The document summarizes research investigating the influence of infinite impedance flanges on the electromagnetic field of a plane waveguide. It presents the theoretical background, describing the problem of analyzing the EM field behavior from the open end of a parallel-plate waveguide. It then details the solution approach using integral equations and the method of moments technique. Numerical results are presented demonstrating the effects of impedance flanges and edge features on the EM field and radiation patterns.
The document summarizes research investigating the influence of infinite impedance flanges on the electromagnetic field of a plane waveguide. It presents the theoretical background, describing the problem of analyzing the EM field behavior from the open end of a parallel-plate waveguide. It then details the solution approach using integral equations and the method of moments technique. Numerical results are presented demonstrating the effects of impedance flanges and edge features on the EM field and radiation patterns.
Piezoelectricity involves using crystals that generate an electric charge in response to applied mechanical stress. Some materials that exhibit piezoelectricity include quartz, bone, wood, and synthetic ceramics. The document discusses the piezoelectric effect and electromechanical effect at the crystal structure level. It also provides the mathematical descriptions and constitutive equations for relating mechanical and electrical behavior in piezoelectric materials. The main applications discussed are piezoelectric actuators and transducers used in microelectromechanical systems.
A general theoretical design of semiconductor nanostructures withAlexander Decker
This document presents a theoretical design for semiconductor nanostructures with equispaced energy levels, specifically for quantum wells in semiconductor ternary alloys. The procedure maps the envelope function Schrodinger equation for a realistic quantum well into an effective-mass Schrodinger equation with a linear harmonic oscillator potential through coordinate transformation. This allows the electron effective mass and potential to be obtained, providing signatures for the equispaced energy levels in quantum wells of semiconductor ternary alloys. Preliminary results are presented for ternary alloy quantum wells, with the goal of generalizing previous studies and obtaining solutions that depict the signatures for equispaced energy levels.
Hamiltonian Approach for Electromagnetic Field in One-dimensional Photonic Cr...IRJET Journal
1) The document presents a novel Hamiltonian approach for determining the classical electromagnetic field distribution in one-dimensional photonic crystals.
2) The approach starts from a microscopic Hamiltonian describing the interaction between quantized electromagnetic fields and medium oscillators. Approximations are made to derive a macroscopic Hamiltonian in terms of averaged field operators and material susceptibilities.
3) Using the macroscopic Hamiltonian and coherent states of the electromagnetic field, the electric field operator for the photonic crystal is obtained. The expectation value of this operator gives the classical electric field distribution inside the photonic crystal.
4) As an example, the electric field distribution in a one-dimensional photonic crystal of alternating dielectric layers is determined and a phot
Study of Multiple Plasmon Resonance based Broadband Cross- Polarization Conve...IRJET Journal
This document presents the design and simulation of a broadband metasurface for cross-polarization conversion (CPC). The metasurface consists of a periodic array of split-ring resonators (SRRs) with a circular split-ring resonator (C-SRR) printed within each SRR. Simulation results show the metasurface achieves over 73% fractional bandwidth for CPC between 5-15 GHz. Multiple plasmonic resonances at 5.5 GHz, 8.2 GHz, and 14.1 GHz contribute to the broadband performance. The metasurface exhibits stable CPC for both normal and oblique incidences due to its subwavelength unit cell size and symmetric structure.
This document compares the harvesting of energy from vibration using a magnetostrictive material (Metglas2605SC) under harmonic and random excitation. It presents a linear model of a single degree of freedom vibration energy harvesting system (mass-spring-damper) and derives the governing equations. It then analyzes the system under random excitation applied to the support and compares the output current and harvested energy for different substrate materials (silicon, steel, copper, silver, gold). The results show that the output current and power is highest for gold substrates and that random excitation produces lower output current than harmonic excitation for the same copper substrate.
Similar to Electroelastic Response of a Piezoelectric Semi-infinite Body with D∞ Symmetry to Surface Friction (20)
Presentation of IEEE Slovenia CIS (Computational Intelligence Society) Chapte...University of Maribor
Slides from talk presenting:
Aleš Zamuda: Presentation of IEEE Slovenia CIS (Computational Intelligence Society) Chapter and Networking.
Presentation at IcETRAN 2024 session:
"Inter-Society Networking Panel GRSS/MTT-S/CIS
Panel Session: Promoting Connection and Cooperation"
IEEE Slovenia GRSS
IEEE Serbia and Montenegro MTT-S
IEEE Slovenia CIS
11TH INTERNATIONAL CONFERENCE ON ELECTRICAL, ELECTRONIC AND COMPUTING ENGINEERING
3-6 June 2024, Niš, Serbia
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.
KuberTENes Birthday Bash Guadalajara - K8sGPT first impressionsVictor Morales
K8sGPT is a tool that analyzes and diagnoses Kubernetes clusters. This presentation was used to share the requirements and dependencies to deploy K8sGPT in a local environment.
Electric vehicle and photovoltaic advanced roles in enhancing the financial p...IJECEIAES
Climate change's impact on the planet forced the United Nations and governments to promote green energies and electric transportation. The deployments of photovoltaic (PV) and electric vehicle (EV) systems gained stronger momentum due to their numerous advantages over fossil fuel types. The advantages go beyond sustainability to reach financial support and stability. The work in this paper introduces the hybrid system between PV and EV to support industrial and commercial plants. This paper covers the theoretical framework of the proposed hybrid system including the required equation to complete the cost analysis when PV and EV are present. In addition, the proposed design diagram which sets the priorities and requirements of the system is presented. The proposed approach allows setup to advance their power stability, especially during power outages. The presented information supports researchers and plant owners to complete the necessary analysis while promoting the deployment of clean energy. The result of a case study that represents a dairy milk farmer supports the theoretical works and highlights its advanced benefits to existing plants. The short return on investment of the proposed approach supports the paper's novelty approach for the sustainable electrical system. In addition, the proposed system allows for an isolated power setup without the need for a transmission line which enhances the safety of the electrical network
Literature Review Basics and Understanding Reference Management.pptxDr Ramhari Poudyal
Three-day training on academic research focuses on analytical tools at United Technical College, supported by the University Grant Commission, Nepal. 24-26 May 2024
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.
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%.
International Conference on NLP, Artificial Intelligence, Machine Learning an...gerogepatton
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.
Electroelastic Response of a Piezoelectric Semi-infinite Body with D∞ Symmetry to Surface Friction
1. Masayuki Ishihara et al. Int. Journal of Engineering Research and Applications www.ijera.com
ISSN : 2248-9622, Vol. 5, Issue 6, ( Part -2) June 2015, pp.26-32
www.ijera.com 26 | P a g e
Electroelastic Response of a Piezoelectric Semi-infinite Body with
D∞ Symmetry to Surface Friction
Masayuki Ishihara*, Yoshihiro Ootao**, and Yoshitaka Kameo***
*(Graduate School of Engineering, Osaka Prefecture University;)
**(Graduate School of Engineering, Osaka Prefecture University;)
***(Institute for Frontier Medical Sciences, Kyoto University;)
ABSTRACT
In this paper, with the aim of developing a nondestructive evaluation technique using piezoelectric signals in
wooden materials, we theoretically study the electroelastic field in a semi-infinite body with D∞ symmetry
subjected to surface friction parallel to the ∞-fold rotation axis. By applying the analytical technique previously
proposed by us, we formulate expressions for electroelastic field quantities, including electric potential, electric
field, electric displacement, elastic displacement, strain, and stress by using two “elastic displacement potential
functions” and two “piezoelastic displacement potential functions.” These potential functions and, consequently,
the electroelastic field quantities are formulated using Fourier transforms in order to satisfy electroelastic
boundary conditions. We carried out numerical calculations to correctly evaluate field quantities inside the body
and at its surface. As a result, we were successful in quantitatively elucidating the surface electric displacement
in response to the elastic stimulus of surface friction and suggested the possibility of a nondestructive evaluation
technique using piezoelectric signals.
Keywords - D∞ symmetry, electroelastic problem, piezoelectric body, theoretical analysis
I. Introduction
Because of rising demands to reduce the global
carbon footprint, wooden materials have attracted
considerable attention in engineering production as
“carbon-neutral” materials. To ensure wooden
materials of satisfactory quality, nondestructive
evaluation techniques need to be developed. The
electroelastic behaviors of wood, which is known as
a piezoelectric material [1], have been investigated
using piezoelectric effects. Piezoelectric signals
were related to the profiles of defects [2-4],
deformation [5, 6], and the stress–strain relation [7,
8].
Because wooden materials contain complicated
microstructures, their detailed electroelastic behavior
needs to be investigated from a microscopic
standpoint. Such an approach, however, entails a
considerably high computational cost and is
impractical for engineering applications. Therefore,
a macroscopic approach is required. From a
macroscopic viewpoint, woods are generally
recognized as orthotropic materials with their
principal axes in the longitudinal, radial, and
tangential directions [9, 10].
Furthermore, according to another approach,
woods are considered to have D symmetry [5-8].
This is the consequence of an aggregation of natural
cellulose chains in a certain manner [1, 8]. D
symmetry is characterized by an “ -fold rotation
axis” and a “two-fold rotation axis” perpendicular to
it [11]. In other words, the material is isotropic
within the plane perpendicular to the longitudinal
direction. One of the most striking characteristics of
a body with D symmetry is the coupling between
the shear strain (or shear stress) in the plane parallel
to the -fold rotation axis and the electric field (or
electric displacement) perpendicular to the plane.
Considering the importance of electroelastic
problems in wooden materials, we developed an
analytical technique to obtaining general solutions to
coupled electroelastic problems in bodies with D
symmetry, and presented new possibilities in the
theoretical investigation of the electroelastic
behavior of wooden materials [12]. In that study, by
way of a trial application of the technique, we
treated a semi-infinite body and investigated the
response of “elastic quantities,” such as stress and
strain, resulting from “electric stimulus” by an
electric potential on its surface. In order to develop
nondestructive evaluation techniques, however, the
response of electric quantities due to elastic stimuli
need to be elucidated.
In this paper, therefore, we study the
electroelastic field in a semi-infinite body subjected
to surface friction parallel to the -fold rotation
axis in order to explore techniques of nondestructive
evaluation. By applying the analytical technique
previously proposed by us [12], electroelastic field
quantities, including electric potential, electric field,
electric displacement, elastic displacement, strain,
RESEARCH ARTICLE OPEN ACCESS
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and stress, can be expressed by two “elastic
displacement potential functions” and two
“piezoelastic displacement potential functions.”
These potential functions and, consequently, the
electroelastic field quantities are formulated to
satisfy electroelastic boundary conditions. Moreover,
we performed numerical calculations to investigate
the effects of the elastic stimulus modeled by the
surface friction on the electric quantities.
II. Theoretical analysis
2.1 Problem
xy
z
y
z
x
),(0 zyf
Fig. 1: Analytical model
We consider a semi-infinite piezoelectric body
0x with D symmetry, as shown in Fig. 1,
where the z -axis is parallel to the -fold rotation
axis of the body. The surface of the body is
subjected to surface friction zyf ,0 , which is anti-
symmetric and symmetric with respect to y and z ,
respectively. The surface 0x is chosen as the
reference plane of electric potential. The
displacements and electric potential are assumed to
be zero at infinity. Our purpose in this section is to
formulate the components of displacement, strain,
stress, electric field, and electric displacement in the
Cartesian coordinate system zyx ,, , which are
denoted as zyx uuu ,, , xyzxyzzzyyxx ,,,,, ,
xyzxyzzzyyxx ,,,,, , zyx EEE ,, , and
zyx DDD ,, , respectively and to formulate the
electric potential .
2.2 Fundamental equations
The fundamental equations for the problem stated in
Subsection 2.1 are provided by the displacement-
strain relations
x
u
y
u
z
u
x
u
y
u
z
u
z
u
y
u
x
u
yx
xy
xz
zx
zy
yz
z
zz
y
yy
x
xx
2
,2,2
,,,
, (1)
the relation between the electric potential and
electric field
z
E
y
E
x
E zyx
,, , (2)
the constitutive equations
z
y
x
xy
zx
yz
zz
yy
xx
xy
zx
yz
zz
yy
xx
E
E
E
e
e
cc
c
c
c
cc
ccc
000
00
00
000
000
000
2
2
2
2
sym.
0
00
000
000
000
14
14
1211
44
44
33
1311
131211
, (3)
z
y
x
xy
zx
yz
zz
yy
xx
z
y
x
E
E
E
e
e
D
D
D
33
11
11
14
14
sym.
0
00
2
2
2
000000
00000
00000
, (4)
the equilibrium equations of stresses
0
,0
,0
yxz
xzy
zyx
yzzxzz
xyyzyy
zxxyxx
, (5)
and Gauss’s law
0
z
D
y
D
x
D zyx
, (6)
where ijc , kl , and kje denote the elastic stiffness
constant, dielectric constant, and piezoelectric
constant, respectively [12]. The boundary conditions
are then described as
0,,,:
;0,0,0,,:0
222
0
zyx
xyxxzx
uuuzyx
zyfx
. (7)
2.3 Potential function method
According to the analytical technique previously
proposed by us [12], the electroelastic field
quantities are described by elastic displacement
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potential functions i , piezoelastic displacement
potential functions i , certain constants ik 2,1i ,
and electric potential as follows:
2
1
2
1
2
1
,,
i
iiz
i
ii
y
i
ii
x
k
z
u
xy
u
yx
u
, (8)
z
E
y
E
x
E zyx
,, , (9)
2
1
2
2
2
22
2
1
22
2
1
22
2
1
2
22
1
2
2
2
2
1
2
2
2
22
,12
,12
,,
,
i
iii
xy
i
ii
izx
i
ii
iyz
i
i
izz
i
ii
yy
i
ii
xx
yxyx
zyxz
k
xzzy
k
z
k
yxy
yxx
. (10)
The components of stress and electric displacement
are obtained by a simple algebraic operation, namely
by substituting equations (9) and (10) into equations
(3) and (4). For the sake of brevity, only the
components closely related to the boundary
conditions and electroelastic coupling are shown as
yzyxz
keD
xxzzy
keD
y
e
zyxz
kc
x
e
xzzy
kc
yxyx
cc
yx
cc
z
ck
y
c
x
c
i
ii
iy
i
ii
ix
i
ii
izx
i
ii
iyz
i
iii
xy
i
i
i
i
ii
xx
11
2
1
22
14
11
2
1
22
14
14
2
1
22
44
14
2
1
22
44
2
1
2
2
2
22
1211
2
1
2
1211
2
2
132
2
122
2
11
1
,1
,1
,1
,2
2
,
. (11)
The governing equations for i , i , and are
given by
2
1
2
2
32
2
2
2
3
44
14
2
2
2
2
2
2
2
2
2
2
2
2
,0
,0
i
i
ii
ii
zyxzc
e
zyx
zyx
, (12)
where 1 and 2 are the roots of a quadratic
equation with respect to
02 44334413
2
133311
2
4411 ccccccccc ,(13)
1 and 2 are the roots of a quadratic equation with
respect to
01 3
2
couple3
2
k ; (14)
1144
2
142
couple
11
33
1211
44
3 ,,
2
c
e
k
cc
c
, (15)
and
i
ii
i
cc
cc
cc
cc
k
4433
4413
4413
4411
. (16)
2.4 Formulae for electroelastic field quantities
As described in Subsection 2.1, the surface friction
zyf ,0 is anti-symmetric and symmetric with
respect to y and z , respectively, and so is the
surface shear stress zx obtained from equation (7).
By referring to the fourth equation in equations (11),
we find that i is antisymmetric with respect to y
and z , and that i is symmetric and antisymmetric
with respect to y and z , respectively. By
considering these symmetric and anti-symmetric
properties and the finiteness of the electroelastic
field described by the second equation in equation
(7), and applying the Fourier transform [13] to
equation (12), the solutions for i and i 2,1i
are obtained as
21222122
0 0
0 0
,
dd
sincos
exp,
,dd
sinsin
exp,
iiii
ii
i
ii
i
zy
xC
zy
xA
, (17)
which in turn give
2
1
0 0
3
314
44
dd
coscos
exp,
1
i
iii
zy
xC
e
c
... (18)
from the third equation in equation (12).
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By substituting equations (17) and (18) into
equations (8)-(11), the electroelastic field quantities
are obtained. For the sake of brevity, only the
components of equation (11) are shown as
2
1
0 0
2
couple3
2
couple3
314
1144
2
1
0 0
2
couple3
2
couple3
314
1144
2
1
0 0
3
3
44
2
1
0 0
3
3
44
2
1
0 0
22
3
44
2
1
0 0
2
3
2
3
44
ddcossin
exp,
1
exp,
1
,
ddcoscos
exp,
1
exp,
1
,
ddcossin
exp,
exp,
1
,
ddcoscos
exp,
exp,
1
,
ddsincos
exp,
2
exp,2
,
ddsinsin
exp,2
exp,
12
i
ii
i
ii
ii
y
i
ii
ii
ii
i
x
i iii
ii
ii
zx
i iiii
ii
i
yz
i ii
i
iii
xy
i iii
ii
i
xx
zy
xC
k
xA
kk
e
c
D
zy
xC
k
xA
kk
e
c
D
zy
xC
xA
k
c
zy
xC
xA
k
c
zy
xC
xA
c
zy
xC
xA
k
c
.
... (19)
The distribution function for surface friction,
zyf , , is expressed in Fourier integral form [13] as
0 0
*
ddcossin,, zyfzyf , (20)
where
0 02
*
ddcossin,
4
, zyzyzyff
. (21)
By substituting equations (18)-(20) into equation (7),
a set of simultaneous equations for ,iA and
,iC 2,1i is obtained as
0,
,0,2,2
,
,
,,1
,0
,2
,12
2
1
3
2
1
22
*
44
03
2
1
3
2
1
2
3
2
i
ii
i
iiii
i
iiiii
i ii
ii
C
CA
f
c
CAk
C
Ak
.(22)
The solution to this is obtained as
,
,
,
,
,
1,
,
,
,
,
*
2
*
1
*
2
*
1
*
44
0
2
1
2
1
C
C
A
A
f
c
C
C
A
A
(23)
together with
122121
2
3
2
21
13
*
2
122121
2
3
2
21
23
*
1
1221213
2
1
2
3
22
31
2
21
*
2
1221213
2
2
2
3
22
32
2
21
*
1
2211
4
21
22
3
2
213
21
2
32121
2
21
21
2121
2
21213
2
2,
,
2
2,
,4
212
,
,4
212
,
,
4
2
11
2
22
,
kk
C
kk
C
k
A
k
A
kk
kk
kk
kk
.
... (24)
By substituting equations (23) and (24) into equation
(19), the electroelastic field quantities are
formulated. Thus, our purpose in this section has
been attained. Although for a simple model, these
formulae are advantageous in that they enable us to
evaluate field quantities without errors, and to
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investigate quantities inside the body, namely
experimentally-unmeasurable quantities.
III. Numerical calculation
3.1 Numerical specifications
The distribution function for surface friction,
zyf , , is assumed to have a Rayleigh distribution
with respect to y and a Gaussian distribution with
respect to z , with an effective width as
2
2
2
2
expexp,
zyy
zyf , (25)
for which equation (21) is calculated as
4
exp
2
,
223
*
f . (26)
It should be noted that zyf , in Fig. 1 is shown
actually as defined by equation (25).
As an example of a piezoelectric body, we chose
Sitka spruce (Picea sitchensis). Although a complete
set of its material constants was not found in a
common condition or in the form of equations (3)
and (4), it was built in our past work [12] as
2-3
14
2-1-212
33
2-1-212
11
44
1312
3311
Cm1014850.0
,mNC10490.22
,mNC10823.16
,MPa50.742
,MPa07.472,MPa47.294
,GPa276.12,MPa84.830
e
c
cc
cc
. (27)
To show the numerical results, we introduced the
following nondimensional quantities:
44
0140
44
33131211
33131211
,
,,
,
,
,
,,,
,,,
,
,,
,,
c
e
DD
DD
c
cccc
cccc
zyx
zyx
yx
yx
zxyz
zxyz
. (28)
For brevity, we hereafter omit the signs for
nondimensional quantities, ⌒.
3.2 Distributions of field quantities
Figure 2, which is expressed by equation (19), shows
the distribution of stress zx inside the body. From
Fig. 2, we see that stress zx is maximum at the
surface 0x and decreases monotonically toward
zero with x to satisfy the finiteness of the field
described by equation (7). Figure 2 shows one of the
most important aspects of this study: electroelastic
field quantities inside the body, which are nearly
impossible to obtain experimentally, are obtained.
-0.4
-0.35
-0.3
-0.25
-0.2
-0.15
-0.1
-0.05
0
0 0.5 1 1.5 2 2.5 3 3.5 4
x
zx
0y
5.0y
1y
2y
Fig. 2: Distribution of stress zx inside the body
0z
Figures 3 and 4 show the distributions of stress
zx and yz , respectively, on the surface 0x . It
should be noted that the direction of the y -axis was
taken as in the left part of Fig. 1. By referring to Fig.
1, which shows the distribution of zyf , as
defined by equation (25), we found that the
numerical results in Fig. 3 satisfied the boundary
condition described by the first equation in equations
(7), namely zyfxzx ,0
. From Fig. 4, we
found that stress yz , for respective values of z ,
was positive and maximum at 0y , decreased to a
negative and minimum value with y , and finally
converged to zero for y to satisfy the
finiteness of the field described by equation (7).
-0.45
-0.4
-0.35
-0.3
-0.25
-0.2
-0.15
-0.1
-0.05
0
4 3.5 3 2.5 2 1.5 1 0.5 0
y
zx
0z
5.0z
1z
2z
4z
Fig. 3: Distribution of stress zx on the surface
0x
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-0.15
-0.1
-0.05
0
0.05
0.1
0.15
0.2
0.25
0.3
4 3.5 3 2.5 2 1.5 1 0.5 0
y
yz
0z
5.0z
1z
2z
4z
Fig. 4: Distribution of stress yz on the surface
0x
Figures 5 and 6 show that the magnitudes of
electric displacements xD and yD were maximum
at the surface 0x , and decreased to zero with x .
Figures 5 and 6 also show the important aspect
mentioned with regard to Fig. 2 above because both
figures elucidate experimentally-unmeasurable
quantities.
At the same time, experimentally-measurable
responses to disturbances need to be investigated
from the viewpoint of nondestructive evaluation
techniques. By regarding surface friction zyf , in
Fig. 1 as such a disturbance, the electric
displacement xD on the surface 0x is one of the
candidates for such a response. From this viewpoint,
the distribution of electric displacement xD on the
surface 0x is shown in Fig. 7, where the direction
of the y -axis was taken as that in Fig. 4. By
comparing Fig. 7 with Fig. 4, we found that the
variations in electric displacement xD with y for
various values of z were roughly proportional to
those of stress yz . This tendency was considered to
be a consequence of the coupling behavior in yz ,
yz , xD , and xE through the piezoelectric constant
14e in the fourth and first lines of equations (3) and
(4), respectively, and suggested the possibility of a
nondestructive evaluation technique using
piezoelectric signals. Although the electroelastic
response discussed in this paper occurred due to the
disturbance defined in equation (25), responses for
other disturbances can be easily investigated by
updating zyf , in equation (21). Furthermore, we
expect that various configurations of the body,
including bodies with defects such as notches,
cracks, or inclusions, can be analyzed because the
governing equations (12) for i and i are
essentially the Laplace equations, which are
mathematically well established.
-0.25
-0.2
-0.15
-0.1
-0.05
0
0.05
0.1
0 0.5 1 1.5 2 2.5 3 3.5 4
x
xD
Fig. 5: Distribution of electric displacement xD
inside the body 0z
-0.4
-0.35
-0.3
-0.25
-0.2
-0.15
-0.1
-0.05
0
0 0.5 1 1.5 2 2.5 3 3.5 4
x
yD
0y
5.0y
1y
2y
Fig. 6: Distribution of electric displacement yD
inside the body 0z
-0.2
-0.15
-0.1
-0.05
0
0.05
0
0.5
1
1.5
2
2.5
3
3.5
4
4 3.5 3 2.5 2 1.5 1 0.5 0
y
xD
z
Fig. 7: Distribution of electric displacement xD on
the surface 0x
IV. Concluding remarks
In this paper, we studied the electroelastic field
in a semi-infinite body with D symmetry subjected
to surface friction. We theoretically formulated
electroelastic field quantities by the potential
function method and obtained the distributions of
electroelastic field quantities inside the body by
numerical calculations. These achievements,
although their success depends on the characteristics
of the model, have a great significance because they
7. Masayuki Ishihara et al. Int. Journal of Engineering Research and Applications www.ijera.com
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enable us to accurately evaluate actual field
quantities and to investigate experimentally-
unmeasurable quantities.
Moreover, we quantitatively investigated the
surface electric displacement in response to an
elastic stimulus of the surface friction and suggested
the possibility of a nondestructive evaluation
technique using piezoelectric signals.
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