We present a method by which to determine the bulk viscosity of water from pulse duration measurements of stimulated Brillouin scattering （SBS）. Beginning from a common model of Brillouin scattering, the bulk viscos...We present a method by which to determine the bulk viscosity of water from pulse duration measurements of stimulated Brillouin scattering （SBS）. Beginning from a common model of Brillouin scattering, the bulk viscosity is shown to play an important role in Brillouin linewidth determination. Pulse durations of SBS back-reflected optical pulses are measured over the temperature range of 5-40℃. SBS linewidths are de- termined via Fourier transformation of the time-domain results, and the bulk viscosity of water is measured and derived from the obtained values. Our results show that the proposed method for measurement of pulse durations is an effective approach for determining bulk viscosity. The method can be easily extended to determine bulk viscosities of other Newtonian liquids.展开更多
Real-time single-shot measurement of the femtosecond electron beam duration in laser wakefield accelerators is discussed for both experimental design and theoretical analysis that combines polarimetry and interferomet...Real-time single-shot measurement of the femtosecond electron beam duration in laser wakefield accelerators is discussed for both experimental design and theoretical analysis that combines polarimetry and interferometry.The probe pulse polarization is rotated by the azimuthal magnetic field of the electron beam and then introduced into a Michelson-type interferometer for self-interference. The electron beam duration is obtained from the region size of the interference fringes, which is independent of the pulse width of the probe laser. Using a larger magnification system or incident angle, the measurement resolution can be less than 1 fs.展开更多
This paper aims to design an automated Global Reporting Format’s (GRF) application in order to reduce time of manual application (on a runway) of the Global Reporting Format developed by International Civil Aviation ...This paper aims to design an automated Global Reporting Format’s (GRF) application in order to reduce time of manual application (on a runway) of the Global Reporting Format developed by International Civil Aviation Organization (ICAO). A method has been used to measure and generate Runway Condition Report (RCR) automatically. The developed computing model is an autonomous and automatic application implemented specially for West Africa (and can be extended to any rainy area). It uses Arduino materials and computing code developed by the authors. Results obtained show that using that method to retrieve the Runway Condition Report (RCR) is fast, so human presence on the runway is reduced. Even though the results obtained using this model are slightly different from those expected, the actual runway conditions are not too much affected.展开更多
基金supported by the National Natural Sci-ence Foundation of China under Grants Nos.41206084 and 61177096
文摘We present a method by which to determine the bulk viscosity of water from pulse duration measurements of stimulated Brillouin scattering （SBS）. Beginning from a common model of Brillouin scattering, the bulk viscosity is shown to play an important role in Brillouin linewidth determination. Pulse durations of SBS back-reflected optical pulses are measured over the temperature range of 5-40℃. SBS linewidths are de- termined via Fourier transformation of the time-domain results, and the bulk viscosity of water is measured and derived from the obtained values. Our results show that the proposed method for measurement of pulse durations is an effective approach for determining bulk viscosity. The method can be easily extended to determine bulk viscosities of other Newtonian liquids.
基金supported by the National Natural Science Foundation of China(Nos.11127901,11425418,11505263,and 61521093)the Strategic Priority Research Program(B)(No.XDB16)+2 种基金Shanghai Sailing Program(Nos.17YF1421100 and 18YF1426000)the Youth Innovation Promotion Association CASthe State Key Laboratory Program of the Chinese Ministry of Science and Technology
文摘Real-time single-shot measurement of the femtosecond electron beam duration in laser wakefield accelerators is discussed for both experimental design and theoretical analysis that combines polarimetry and interferometry.The probe pulse polarization is rotated by the azimuthal magnetic field of the electron beam and then introduced into a Michelson-type interferometer for self-interference. The electron beam duration is obtained from the region size of the interference fringes, which is independent of the pulse width of the probe laser. Using a larger magnification system or incident angle, the measurement resolution can be less than 1 fs.
文摘This paper aims to design an automated Global Reporting Format’s (GRF) application in order to reduce time of manual application (on a runway) of the Global Reporting Format developed by International Civil Aviation Organization (ICAO). A method has been used to measure and generate Runway Condition Report (RCR) automatically. The developed computing model is an autonomous and automatic application implemented specially for West Africa (and can be extended to any rainy area). It uses Arduino materials and computing code developed by the authors. Results obtained show that using that method to retrieve the Runway Condition Report (RCR) is fast, so human presence on the runway is reduced. Even though the results obtained using this model are slightly different from those expected, the actual runway conditions are not too much affected.
