In order to study the thermoelectric efficiency of microwave heating and reproduction of asphalt pavements and the uniformity of reproduction temperature distribution, a waveguide excitation cavity is designed and app...In order to study the thermoelectric efficiency of microwave heating and reproduction of asphalt pavements and the uniformity of reproduction temperature distribution, a waveguide excitation cavity is designed and applied to the structural design of a microwave heater. The structural sizes of the incentive cavities are determined based on the waveguide transmission line theory. Using IE3D software, electromagnetic simulations are respectively carried out in four different situations, including the distances between the magnetron probes (antennas) and a short-circuit board, different horn electric lengths and aperture sizes, different dielectric properties of the asphalt mixture, and the distances between the asphalt surface and the mouth cavity. The results show that, when the distance between the magnetron probe and the short-circuit board is 32.5 ram, it is the best installation site; reduction of aerial length is the main factor in improving the heating uniformity. When the aggregate is limestone, the best heating effect can be produced. Maximum radiation efficiency can be realized by adjusting the space between the heater radiation port and the asphalt pavement. The experimental results of asphalt mixture heating in four different situations have a substantial agreement with the simulation results, which confirms that the developed microwave heater can achieve better impedance matching, thus improving the quality and efficiency of heating regeneration.展开更多
In this paper we study the mean first passage time (MFPT) over a fluctuation potential barrier driven by a coupled noise. It is shown that the MFPT over the fluctuation potential barrier displays resonant activation...In this paper we study the mean first passage time (MFPT) over a fluctuation potential barrier driven by a coupled noise. It is shown that the MFPT over the fluctuation potential barrier displays resonant activations as the function of the flipping rate of the fluctuation potential barrier, and as the function of the dichotomous noise transition rate.展开更多
Theoretical analyses have been performed to describe the coupling losses for a plane mirror in rectangular waveguide resonator for an arbitrary waveguide mode as a function of the Fresnel number for several values of ...Theoretical analyses have been performed to describe the coupling losses for a plane mirror in rectangular waveguide resonator for an arbitrary waveguide mode as a function of the Fresnel number for several values of the aspect ratio by using Fresnel approximation.展开更多
We recently proposed a new class of wavelength-swept lasers for swept-source optical coherence tomography (SS-OCT). It uses the same gain medium with the conventional swept lasers, but does not require any tunable f...We recently proposed a new class of wavelength-swept lasers for swept-source optical coherence tomography (SS-OCT). It uses the same gain medium with the conventional swept lasers, but does not require any tunable filters. It is based on a principle called "dispersion tuning", in which a highly dispersive medium is inserted in the laser cavity, and loss/gain modulation is applied to mode-lock the laser. Since the cavity contains no mechanical components, such as tunable filters, we could achieve the very high sweep rate. In this review paper, we describe the principle of the dispersion-tuned swept lasers in detail and present our recent work on the application to the SS-OCT system.展开更多
In the present paper the problem of nonlinear interaction of two mildly-relativistic circularly polarized lasers in a cold plasma is studied in order to investigate electromagneticaily induced transparency (EIT). Ba...In the present paper the problem of nonlinear interaction of two mildly-relativistic circularly polarized lasers in a cold plasma is studied in order to investigate electromagneticaily induced transparency (EIT). Based on a relativistic kinetic model, by expansion of relativistic Lorentz factor in terms of lasers amplitude, we obtain the coupled nonlinear dispersion relations. It is observed that due to resonance in the second harmonic of plasma beat-wave, the new EIT pass-band is created in the high intensities of lasers. The effect of amplitude and frequency variation on the dispersion is numerically investigated.展开更多
基金The Sci-Tech Achievements Transformation Program of Colleges and Universities in Jiangsu Province(No.JH09-13)the Research Fund of Nanjing Institute of Technology(No.YKJ201005)
文摘In order to study the thermoelectric efficiency of microwave heating and reproduction of asphalt pavements and the uniformity of reproduction temperature distribution, a waveguide excitation cavity is designed and applied to the structural design of a microwave heater. The structural sizes of the incentive cavities are determined based on the waveguide transmission line theory. Using IE3D software, electromagnetic simulations are respectively carried out in four different situations, including the distances between the magnetron probes (antennas) and a short-circuit board, different horn electric lengths and aperture sizes, different dielectric properties of the asphalt mixture, and the distances between the asphalt surface and the mouth cavity. The results show that, when the distance between the magnetron probe and the short-circuit board is 32.5 ram, it is the best installation site; reduction of aerial length is the main factor in improving the heating uniformity. When the aggregate is limestone, the best heating effect can be produced. Maximum radiation efficiency can be realized by adjusting the space between the heater radiation port and the asphalt pavement. The experimental results of asphalt mixture heating in four different situations have a substantial agreement with the simulation results, which confirms that the developed microwave heater can achieve better impedance matching, thus improving the quality and efficiency of heating regeneration.
基金The project supported by National Natural Science Foundation of China under Grant No. 10375009, and the Scientific Research Foundation for the Returned 0verseas Chinese Scholars, State Education Ministry and by K.C. Wong Magna Fund in Ningbo University
文摘In this paper we study the mean first passage time (MFPT) over a fluctuation potential barrier driven by a coupled noise. It is shown that the MFPT over the fluctuation potential barrier displays resonant activations as the function of the flipping rate of the fluctuation potential barrier, and as the function of the dichotomous noise transition rate.
文摘Theoretical analyses have been performed to describe the coupling losses for a plane mirror in rectangular waveguide resonator for an arbitrary waveguide mode as a function of the Fresnel number for several values of the aspect ratio by using Fresnel approximation.
文摘We recently proposed a new class of wavelength-swept lasers for swept-source optical coherence tomography (SS-OCT). It uses the same gain medium with the conventional swept lasers, but does not require any tunable filters. It is based on a principle called "dispersion tuning", in which a highly dispersive medium is inserted in the laser cavity, and loss/gain modulation is applied to mode-lock the laser. Since the cavity contains no mechanical components, such as tunable filters, we could achieve the very high sweep rate. In this review paper, we describe the principle of the dispersion-tuned swept lasers in detail and present our recent work on the application to the SS-OCT system.
文摘In the present paper the problem of nonlinear interaction of two mildly-relativistic circularly polarized lasers in a cold plasma is studied in order to investigate electromagneticaily induced transparency (EIT). Based on a relativistic kinetic model, by expansion of relativistic Lorentz factor in terms of lasers amplitude, we obtain the coupled nonlinear dispersion relations. It is observed that due to resonance in the second harmonic of plasma beat-wave, the new EIT pass-band is created in the high intensities of lasers. The effect of amplitude and frequency variation on the dispersion is numerically investigated.