Adnan Jahangir - Academia.edu (original) (raw)

Papers by Adnan Jahangir

Mechanics of Solids, Jul 19, 2022

Archive of Applied Mechanics

Archive of Applied Mechanics

This paper presents an analysis on the velocity of reflected waves through piezoelectric semicond... more This paper presents an analysis on the velocity of reflected waves through piezoelectric semiconductor medium. The medium is set on rotation with constant angular velocity about the axis of symmetry. The concept of nonlocal elasticity is considered, where the stress defined at some specific point is a function of strain at all neighboring points. Elastic distortion caused by an incident wave results in generation of four nonzero waves propagating back in the medium after reflection from the boundary z 0. The heat conduction that propagates through the medium is encountered by the theory of phase lags model along with fractionalorder time derivative. Secular equation involving the wave number is computed to study the nature of waves reflected. Special properties like velocities, attenuation coefficient and specific heat loss are further discussed using the obtained secular equations. The analytical results obtained are computed graphically for a particular material, ZnO with piezoelectric properties. Graphically, we have studied the influence of fractional-order time derivative, nonlocal parameter and rotational effect on properties of waves propagating through the medium.

I am sincere with my profession and trying to achieve the highest of my field, I am looking forwa... more I am sincere with my profession and trying to achieve the highest of my field, I am looking forward to work for a reputable organization that gives employees, opportunities to enhance and utilize their potentials.

Waves in Random and Complex Media

Indian Journal of Physics, 2020

In this study, we emphasize on the reflection of elastic waves through a homogenous micro-stretch... more In this study, we emphasize on the reflection of elastic waves through a homogenous micro-stretch thermoelastic medium. Material and elastic properties of the medium are considered to be temperature-dependent. The medium selected is rotating about an axis with some fixed angular frequency. Initially, the governing equations are formulated with the help of generalized thermoelastic theory. Heat conduction through the medium is encountered by the model proposed by Green and Naghdi. Governing equations are decomposed into longitudinal and transverse components with the help of Helmholtz decomposition principle. Harmonic representation of wave is used to find the solution to the problem. On the basis of solution, it is concluded that after reflection five quasi-waves propagate through the medium. The quasi term basically represents that the polarization vector of particles is not purely perpendicular or parallel to the propagation vector. The rotational frequency of the medium is respon...

The present work is supposed to analyze the propagation of plane harmonic waves in a homogeneous ... more The present work is supposed to analyze the propagation of plane harmonic waves in a homogeneous isotropic medium in the context of generalized dual phase lag model of thermoelasticity. The concept micro-temperature where the microelements have different temperatures is considered. Further, the medium is set on rotation with some specific rotating frequency to examine the wave propagation in rotating media like Earth. The governing equations for present model are solved by using Normal mode analysis method. The theoretical results are obtained for displacement, stress, temperature and micro-temperature distributions, which are also plotted against vertical and horizontal distances. It is found that rotation increases the absolute value of amplitude for plane wave propagating through the medium. By increasing rotation harmonic behavior of wave also increases which in result reduces the attenuation factor.

The effect of relaxation times is studied on plane waves propagating through semiconductor half-s... more The effect of relaxation times is studied on plane waves propagating through semiconductor half-space medium by using the eigen value approach. The bounding surface of the half-space is subjected to a heat flux with an exponentially decaying pulse and taken to be traction free. Solution of the field variables are obtained in the form of series for a general semiconductor medium. For numerical values, Silicon is considered as a semiconducting material. The results are represented graphically to assess the influences of the thermal relaxations times on the plasma, thermal, and elastic waves.

COVID-19 pandemic has halted fast-forwarding activities of the world. Everything has been confine... more COVID-19 pandemic has halted fast-forwarding activities of the world. Everything has been confined to homes with limited physical activity. The imposition of lockdowns has paralyzed activities and public interaction. Consequently, physical fitness has been disadvantaged compromising public health. Restrictions of COVID-19 also put down coaching and sports. Physical training and interaction between players and coaches are significant to improve players performance. The sports sector affected by pandemics due to the low-level education of the players and coaches and lacking knowledge of modern training programs. Technological illiteracy has also added to the adversity, preventing players from getting effective benefits from online training programs. This study explores the challenges to coaching during the COVID-19 pandemic. This research also explores a comparison between direct coaching and online training in this regard. The research emphasizes the scope of maintaining physical fit...

This paper investigates the propagation of surface waves in a rotating fibre-reinforced elastic m... more This paper investigates the propagation of surface waves in a rotating fibre-reinforced elastic media. The general surface wave speed is derived to study the effects of rotation on surface waves in fibrereinforced elastic solid and discussed its particular cases for Stoneley, Rayleigh and Love waves. The results obtained in this investigation are more general in the sense that some earlier published results are obtained from our result as special cases. Also by neglecting the reinforced elastic parameters, the results reduce to well known isotropic medium. It is observed that in a rotating medium the surface waves are dispersive whereas in a non-rotating medium waves are non dispersive. It is also observed that surface wave cannot propagate in a fast rotating medium.

Journal of Engineering and Thermal Sciences

In this paper, estimation is made to investigate the influence of thermal loading due to laser pu... more In this paper, estimation is made to investigate the influence of thermal loading due to laser pulse on elastic waves. The material through which the waves are propagating is homogeneous and isotropic in nature. Heat conduction through the media is analyzed by the model proposed by dual-phase-lag theory (DPL). The governing non-dimensional equations are solved by using the approximated harmonic solution. The expression for the field variables is obtained generally and represented graphically for a particular medium.

Journal of Thermal Stresses

REVIEWS ON ADVANCED MATERIALS SCIENCE

In this article, we analyzed the effect of variable thermal conductivity on reflected elastic wav... more In this article, we analyzed the effect of variable thermal conductivity on reflected elastic waves. The waves are propagating through a thermoelastic medium rotating with some angular frequency. The concept of micro-temperature is also been considered, in which microelements of the medium contain a high temperature. A heat conduction phenomenon is encountered by dual phase-lag heat conduction model. P (or SV)-type wave is incident on the medium with some specific angle of incidence. After reflection from the surface incident, P-wave is converted into quasi longitudinal and quasi transverse waves and propagates back into the medium. Helmholtz’s potential function along with the harmonic wave solution is used to obtain the solution of the model. Analytically, we calculated the amplitude ratios and attenuation factor for each reflected wave against the angle of incidence. The obtained results are also represented graphically for different values of rotational frequency and variable th...

IEEE Electron Device Letters

We present a Verilog-A based compact model for the superconductor-insulator-superconductor (SIS) ... more We present a Verilog-A based compact model for the superconductor-insulator-superconductor (SIS) Josephson junction. The model can generate both hysteretic and non-hysteretic current-voltage (I-V) response for the SIS junctions utilizing the Stewart-McCumber parameter. We calibrate our model with different SIS samples and demonstrate accurate matching between the simulated and experimental results. We implement temperature effect on the energy gap and the critical current of the superconductor to explore the dynamic trends in device characteristics. We calculate the junction inductance and energy as functions of junction current and temperature. We simulate the read/write operations of an SIS junction based cryogenic memory cell to illustrate the usability of our model.

Mathematical and Computer Modelling of Dynamical Systems

ABSTRACT In this article, we explore the three-dimensional boundary-layer flow over an exponentia... more ABSTRACT In this article, we explore the three-dimensional boundary-layer flow over an exponentially stretching surface in two parallel ways. Constitutive equations of a second-grade fluid are used. Instead of classical Fourier’s law, Cattaneo–Christov heat flux model is employed for the formulation of the energy equation. This model can predict the effects of thermal relaxation time on the boundary layer. The resulting partial differential equations are reduced into ordinary differential equations by similarity transformations. Homotopy Analysis Method (HAM) is employed to solve the non-linear problem. Physical impact of emerging parameters on the momentum and thermal boundary-layer thickness are studied.

Results in Physics

Abstract The analysis is made on reflection of waves in thermoelastic micropolar medium. The medi... more Abstract The analysis is made on reflection of waves in thermoelastic micropolar medium. The medium is having an additional property of viscosity, while studying waves the effect of micro-temperature is also been considered. It is found that after reflection three longitudinal and three transverse waves propagate through the medium. Reflected coefficients are calculated for each wave to examine deviation of reflected waves. Results obtained theoretically are shown graphically against angle of incidence. It is analyzed that effect of viscosity and micro-temperature reaches to its maximum level during intermediate values of angle of incident.

Waves in Random and Complex Media

This paper presents a coupled nonlocal elasticity theory and a three-phase lag model to study the... more This paper presents a coupled nonlocal elasticity theory and a three-phase lag model to study the reflection of thermo-elastic wave in a semiconducting nanostructure medium. The nonlocal elasticity...

Mechanics of Solids, Jul 19, 2022

Archive of Applied Mechanics

Archive of Applied Mechanics

This paper presents an analysis on the velocity of reflected waves through piezoelectric semicond... more This paper presents an analysis on the velocity of reflected waves through piezoelectric semiconductor medium. The medium is set on rotation with constant angular velocity about the axis of symmetry. The concept of nonlocal elasticity is considered, where the stress defined at some specific point is a function of strain at all neighboring points. Elastic distortion caused by an incident wave results in generation of four nonzero waves propagating back in the medium after reflection from the boundary z 0. The heat conduction that propagates through the medium is encountered by the theory of phase lags model along with fractionalorder time derivative. Secular equation involving the wave number is computed to study the nature of waves reflected. Special properties like velocities, attenuation coefficient and specific heat loss are further discussed using the obtained secular equations. The analytical results obtained are computed graphically for a particular material, ZnO with piezoelectric properties. Graphically, we have studied the influence of fractional-order time derivative, nonlocal parameter and rotational effect on properties of waves propagating through the medium.

I am sincere with my profession and trying to achieve the highest of my field, I am looking forwa... more I am sincere with my profession and trying to achieve the highest of my field, I am looking forward to work for a reputable organization that gives employees, opportunities to enhance and utilize their potentials.

Waves in Random and Complex Media

Indian Journal of Physics, 2020

In this study, we emphasize on the reflection of elastic waves through a homogenous micro-stretch... more In this study, we emphasize on the reflection of elastic waves through a homogenous micro-stretch thermoelastic medium. Material and elastic properties of the medium are considered to be temperature-dependent. The medium selected is rotating about an axis with some fixed angular frequency. Initially, the governing equations are formulated with the help of generalized thermoelastic theory. Heat conduction through the medium is encountered by the model proposed by Green and Naghdi. Governing equations are decomposed into longitudinal and transverse components with the help of Helmholtz decomposition principle. Harmonic representation of wave is used to find the solution to the problem. On the basis of solution, it is concluded that after reflection five quasi-waves propagate through the medium. The quasi term basically represents that the polarization vector of particles is not purely perpendicular or parallel to the propagation vector. The rotational frequency of the medium is respon...

The present work is supposed to analyze the propagation of plane harmonic waves in a homogeneous ... more The present work is supposed to analyze the propagation of plane harmonic waves in a homogeneous isotropic medium in the context of generalized dual phase lag model of thermoelasticity. The concept micro-temperature where the microelements have different temperatures is considered. Further, the medium is set on rotation with some specific rotating frequency to examine the wave propagation in rotating media like Earth. The governing equations for present model are solved by using Normal mode analysis method. The theoretical results are obtained for displacement, stress, temperature and micro-temperature distributions, which are also plotted against vertical and horizontal distances. It is found that rotation increases the absolute value of amplitude for plane wave propagating through the medium. By increasing rotation harmonic behavior of wave also increases which in result reduces the attenuation factor.

The effect of relaxation times is studied on plane waves propagating through semiconductor half-s... more The effect of relaxation times is studied on plane waves propagating through semiconductor half-space medium by using the eigen value approach. The bounding surface of the half-space is subjected to a heat flux with an exponentially decaying pulse and taken to be traction free. Solution of the field variables are obtained in the form of series for a general semiconductor medium. For numerical values, Silicon is considered as a semiconducting material. The results are represented graphically to assess the influences of the thermal relaxations times on the plasma, thermal, and elastic waves.

COVID-19 pandemic has halted fast-forwarding activities of the world. Everything has been confine... more COVID-19 pandemic has halted fast-forwarding activities of the world. Everything has been confined to homes with limited physical activity. The imposition of lockdowns has paralyzed activities and public interaction. Consequently, physical fitness has been disadvantaged compromising public health. Restrictions of COVID-19 also put down coaching and sports. Physical training and interaction between players and coaches are significant to improve players performance. The sports sector affected by pandemics due to the low-level education of the players and coaches and lacking knowledge of modern training programs. Technological illiteracy has also added to the adversity, preventing players from getting effective benefits from online training programs. This study explores the challenges to coaching during the COVID-19 pandemic. This research also explores a comparison between direct coaching and online training in this regard. The research emphasizes the scope of maintaining physical fit...

This paper investigates the propagation of surface waves in a rotating fibre-reinforced elastic m... more This paper investigates the propagation of surface waves in a rotating fibre-reinforced elastic media. The general surface wave speed is derived to study the effects of rotation on surface waves in fibrereinforced elastic solid and discussed its particular cases for Stoneley, Rayleigh and Love waves. The results obtained in this investigation are more general in the sense that some earlier published results are obtained from our result as special cases. Also by neglecting the reinforced elastic parameters, the results reduce to well known isotropic medium. It is observed that in a rotating medium the surface waves are dispersive whereas in a non-rotating medium waves are non dispersive. It is also observed that surface wave cannot propagate in a fast rotating medium.

Journal of Engineering and Thermal Sciences

In this paper, estimation is made to investigate the influence of thermal loading due to laser pu... more In this paper, estimation is made to investigate the influence of thermal loading due to laser pulse on elastic waves. The material through which the waves are propagating is homogeneous and isotropic in nature. Heat conduction through the media is analyzed by the model proposed by dual-phase-lag theory (DPL). The governing non-dimensional equations are solved by using the approximated harmonic solution. The expression for the field variables is obtained generally and represented graphically for a particular medium.

Journal of Thermal Stresses

REVIEWS ON ADVANCED MATERIALS SCIENCE

In this article, we analyzed the effect of variable thermal conductivity on reflected elastic wav... more In this article, we analyzed the effect of variable thermal conductivity on reflected elastic waves. The waves are propagating through a thermoelastic medium rotating with some angular frequency. The concept of micro-temperature is also been considered, in which microelements of the medium contain a high temperature. A heat conduction phenomenon is encountered by dual phase-lag heat conduction model. P (or SV)-type wave is incident on the medium with some specific angle of incidence. After reflection from the surface incident, P-wave is converted into quasi longitudinal and quasi transverse waves and propagates back into the medium. Helmholtz’s potential function along with the harmonic wave solution is used to obtain the solution of the model. Analytically, we calculated the amplitude ratios and attenuation factor for each reflected wave against the angle of incidence. The obtained results are also represented graphically for different values of rotational frequency and variable th...

IEEE Electron Device Letters

We present a Verilog-A based compact model for the superconductor-insulator-superconductor (SIS) ... more We present a Verilog-A based compact model for the superconductor-insulator-superconductor (SIS) Josephson junction. The model can generate both hysteretic and non-hysteretic current-voltage (I-V) response for the SIS junctions utilizing the Stewart-McCumber parameter. We calibrate our model with different SIS samples and demonstrate accurate matching between the simulated and experimental results. We implement temperature effect on the energy gap and the critical current of the superconductor to explore the dynamic trends in device characteristics. We calculate the junction inductance and energy as functions of junction current and temperature. We simulate the read/write operations of an SIS junction based cryogenic memory cell to illustrate the usability of our model.

Mathematical and Computer Modelling of Dynamical Systems

ABSTRACT In this article, we explore the three-dimensional boundary-layer flow over an exponentia... more ABSTRACT In this article, we explore the three-dimensional boundary-layer flow over an exponentially stretching surface in two parallel ways. Constitutive equations of a second-grade fluid are used. Instead of classical Fourier’s law, Cattaneo–Christov heat flux model is employed for the formulation of the energy equation. This model can predict the effects of thermal relaxation time on the boundary layer. The resulting partial differential equations are reduced into ordinary differential equations by similarity transformations. Homotopy Analysis Method (HAM) is employed to solve the non-linear problem. Physical impact of emerging parameters on the momentum and thermal boundary-layer thickness are studied.

Results in Physics

Abstract The analysis is made on reflection of waves in thermoelastic micropolar medium. The medi... more Abstract The analysis is made on reflection of waves in thermoelastic micropolar medium. The medium is having an additional property of viscosity, while studying waves the effect of micro-temperature is also been considered. It is found that after reflection three longitudinal and three transverse waves propagate through the medium. Reflected coefficients are calculated for each wave to examine deviation of reflected waves. Results obtained theoretically are shown graphically against angle of incidence. It is analyzed that effect of viscosity and micro-temperature reaches to its maximum level during intermediate values of angle of incident.

Waves in Random and Complex Media

This paper presents a coupled nonlocal elasticity theory and a three-phase lag model to study the... more This paper presents a coupled nonlocal elasticity theory and a three-phase lag model to study the reflection of thermo-elastic wave in a semiconducting nanostructure medium. The nonlocal elasticity...