WT5”BZ]A numerical method, the boundary fitted coordinate method (BFC), was used to investigate the transmission and reflection of water waves due to a rigid thin vertical barrier descending from the water surface to...WT5”BZ]A numerical method, the boundary fitted coordinate method (BFC), was used to investigate the transmission and reflection of water waves due to a rigid thin vertical barrier descending from the water surface to a depth, i.e., a curtain-wall type breakwater. A comparison between the present computed results and previous experimental and analytical results was carried out which verifies the prediction of the BFC method. Wave transmission and reflection due to the barrier were computed, and the transmission and refiection coefficients were given in a figure. [WT5”HZ]展开更多
Vertical GaN Schottky barrier diodes with Ti N anodes were fabricated to investigate the electrical performance. The turn-on voltage and specific on-resistance of diodes are deduced to be approximately 0.41 V and 0.98...Vertical GaN Schottky barrier diodes with Ti N anodes were fabricated to investigate the electrical performance. The turn-on voltage and specific on-resistance of diodes are deduced to be approximately 0.41 V and 0.98 mΩ·cm2, respectively.The current-voltage curves show rectifying characteristics under different temperatures from 25℃ to 200℃, implying a good thermal stability of Ti N/Ga N contact. The low-frequency noise follows a 1/f behavior due to the multiple traps and/or barrier inhomogeneous at Ti N/Ga N interface. The trapping/de-trapping between traps and Fermi level causes the slight capacitance dispersion under reverse voltage.展开更多
The effect of porosity on surface wave scattering by a vertical porous barrier over a rectangular trench is studied here under the assumption of linearized theory of water waves.The fluid region is divided into four s...The effect of porosity on surface wave scattering by a vertical porous barrier over a rectangular trench is studied here under the assumption of linearized theory of water waves.The fluid region is divided into four subregions depending on the position of the barrier and the trench.Using the Havelock’s expansion of water wave potential in different regions along with suitable matching conditions at the interface of different regions,the problem is formulated in terms of three integral equations.Considering the edge conditions at the submerged end of the barrier and at the edges of the trench,these integral equations are solved using multi-term Galerkin approximation technique taking orthogonal Chebyshev’s polynomials and ultra-spherical Gegenbauer polynomial as its basis function and also simple polynomial as basis function.Using the solutions of the integral equations,the reflection coefficient,transmission coefficient,energy dissipation coefficient and horizontal wave force are determined and depicted graphically.It was observed that the rate of convergence of the Galerkin method in computing the reflection coefficient,considering special functions as basis function is more than the simple polynomial as basis function.The change of porous parameter of the barrier and variation of trench width and height significantly contribute to the change in the scattering coefficients and the hydrodynamic force.The present results are likely to play a crucial role in the analysis of surface wave propagation in oceans involving porous barrier over submarine trench.展开更多
Oblique surface waves incident on a fixed vertical porous membrane of various geometric configurations is analyzed here.The mixed boundary value problem is modified into easily resolvable problems by using a connectio...Oblique surface waves incident on a fixed vertical porous membrane of various geometric configurations is analyzed here.The mixed boundary value problem is modified into easily resolvable problems by using a connection.These problems are reduced to that of solving a couple of integral equations.These integral equations are solved by a one-term or a two-term Galerkin method.The method involves a basis functions consists of simple polynomials multiplied with a suitable weight functions induced by the barrier.Coefficient of reflection and total wave energy are numerically evaluated and analyzed against various wave parameters.Enhanced reflection is found for all the four barrier configurations.展开更多
文摘WT5”BZ]A numerical method, the boundary fitted coordinate method (BFC), was used to investigate the transmission and reflection of water waves due to a rigid thin vertical barrier descending from the water surface to a depth, i.e., a curtain-wall type breakwater. A comparison between the present computed results and previous experimental and analytical results was carried out which verifies the prediction of the BFC method. Wave transmission and reflection due to the barrier were computed, and the transmission and refiection coefficients were given in a figure. [WT5”HZ]
基金Project supported by the Open Project of State Key Laboratory of Superhard Materials,Jilin University(Grant No.201906)Key Laboratory of Microelectronic Devices and Integrated Technology,Institute of Microelectronics(Grant No.202006)the Science and Technology Program of Ningbo(Grant No.2019B10129).
文摘Vertical GaN Schottky barrier diodes with Ti N anodes were fabricated to investigate the electrical performance. The turn-on voltage and specific on-resistance of diodes are deduced to be approximately 0.41 V and 0.98 mΩ·cm2, respectively.The current-voltage curves show rectifying characteristics under different temperatures from 25℃ to 200℃, implying a good thermal stability of Ti N/Ga N contact. The low-frequency noise follows a 1/f behavior due to the multiple traps and/or barrier inhomogeneous at Ti N/Ga N interface. The trapping/de-trapping between traps and Fermi level causes the slight capacitance dispersion under reverse voltage.
文摘The effect of porosity on surface wave scattering by a vertical porous barrier over a rectangular trench is studied here under the assumption of linearized theory of water waves.The fluid region is divided into four subregions depending on the position of the barrier and the trench.Using the Havelock’s expansion of water wave potential in different regions along with suitable matching conditions at the interface of different regions,the problem is formulated in terms of three integral equations.Considering the edge conditions at the submerged end of the barrier and at the edges of the trench,these integral equations are solved using multi-term Galerkin approximation technique taking orthogonal Chebyshev’s polynomials and ultra-spherical Gegenbauer polynomial as its basis function and also simple polynomial as basis function.Using the solutions of the integral equations,the reflection coefficient,transmission coefficient,energy dissipation coefficient and horizontal wave force are determined and depicted graphically.It was observed that the rate of convergence of the Galerkin method in computing the reflection coefficient,considering special functions as basis function is more than the simple polynomial as basis function.The change of porous parameter of the barrier and variation of trench width and height significantly contribute to the change in the scattering coefficients and the hydrodynamic force.The present results are likely to play a crucial role in the analysis of surface wave propagation in oceans involving porous barrier over submarine trench.
文摘Oblique surface waves incident on a fixed vertical porous membrane of various geometric configurations is analyzed here.The mixed boundary value problem is modified into easily resolvable problems by using a connection.These problems are reduced to that of solving a couple of integral equations.These integral equations are solved by a one-term or a two-term Galerkin method.The method involves a basis functions consists of simple polynomials multiplied with a suitable weight functions induced by the barrier.Coefficient of reflection and total wave energy are numerically evaluated and analyzed against various wave parameters.Enhanced reflection is found for all the four barrier configurations.