A general numerical tool, based on thermal diffusion equation and full-vectorial eigen-mode equation, has been presented for the systematic analysis of graded index channel waveguide fabricated by ion exchange on Er^3...A general numerical tool, based on thermal diffusion equation and full-vectorial eigen-mode equation, has been presented for the systematic analysis of graded index channel waveguide fabricated by ion exchange on Er^3＋ doped glass. Finite difference method with full-vectorial formulation （FV-FDM） is applied to solving the full-vectorial modes of graded index channel waveguide for the first time. The coupled difference equations based on magnetic fields in FV-FDM are derived from the Taylor series expansion and accurate formulation of boundary conditions. Hybrid nature of vectorial guided modes for both pump （980 nm） and signal light （1550 nm） are demonstrated by the simulation. Results show that the fabrication parameters of ion exchange, such as channel opening width and time ratio of second step to first step in ion exchange, have large influence on the properties of waveguide. By optimizing the fabrication parameters, maintenance of monomode for signal light and improvement of the gain dynamics can be achieved in Er^3＋ doped waveguide amplifier （EDWA） fabricated by ion exchange technique. This theoretical model is significant for the design and fabrication of EDWA with ion exchange technique. Furthermore, a single polarization EDWA, which operates at wavelength from 1528 nm to 1541 nm for HE polarization, is numerically designed.展开更多
This paper presents an energy analysis of a counter-flow plate heat exchanger operating in stationary mode. The exchanger comprises a rectangular plate of which we vary the heat transfer surface (by fixing its width a...This paper presents an energy analysis of a counter-flow plate heat exchanger operating in stationary mode. The exchanger comprises a rectangular plate of which we vary the heat transfer surface (by fixing its width and varying its length) and analyze the evolution of some parameters as a function of this heat transfer surface. The parameters to be analyzed are the NTU (number of transfer units), the effectiveness, the temperatures of both primary and secondary fluids and the heat flux. The analysis carried out will help understand the behavior of the counter-flow plate heat exchanger operating in stationary mode. Then, the heat transfer surface of the exchanger is determined for the sizing of a counter-flow plate heat exchanger intended to produce hot air for drying. That plate heat exchanger uses water vapor heated by geothermal energy as a primary fluid and atmospheric air as a secondary fluid. The products to be dried are onions with a mass flow of water to be evacuated of 100 kg/h.展开更多
Based on the principle of minimal energy and the coherent rotation model, two types of the jump phenomena, complete and incomplete jump phenomenon, are proved to exist in the angular dependence of the exchange bias wi...Based on the principle of minimal energy and the coherent rotation model, two types of the jump phenomena, complete and incomplete jump phenomenon, are proved to exist in the angular dependence of the exchange bias with noncollinear unidirectional and uniaxial anisotropies. It is found that the transition between complete and incomplete jump phenomena occurs on condition that the exchange-coupling constant exceeds a critical value. Additionally, two different modes of the magnetization rotation, the whole-plane rotation, and the half-plane rotation are present in the magnetization reversal process, and they are dependent on the direction of the external field. Furthermore, the equations of the critical angle, at which orientation the exchange bias field reaches a maximum value and the coercivity disappears, are also derived in this paper. The numerical calculations in this paper are consistent with the relevant experimental observations, indicating that our method to study the angular dependence of the exchange bias as well as the magnetization reversal behaviors is valid. Our discussion about the jump phenomenon, the critical angle, and the modes of the magnetization reversal can explain the observed differences in results between different experiments.展开更多
This paper investigates the characteristics and evolution process of Sino-Japanese diet culture exchange in each historical period,analyzes the possible impact of globalization on Sino-Japanese diet culture exchange,a...This paper investigates the characteristics and evolution process of Sino-Japanese diet culture exchange in each historical period,analyzes the possible impact of globalization on Sino-Japanese diet culture exchange,and discusses the development direction of innovative mode of Sino-Japanese diet culture exchange under the background of globalization.展开更多
Data exchange between different mode channels is essential in the optical communication network with mode-division multiplexing(MDM).However,there are challenges in realizing mode exchange with low insert loss,low mod...Data exchange between different mode channels is essential in the optical communication network with mode-division multiplexing(MDM).However,there are challenges in realizing mode exchange with low insert loss,low mode crosstalk,and high integration.Here,we designed and fabricated a mode exchange device based on multiplane light conversion(MPLC),which supports the transmission of LP01,LP11a,LP11b,and LP21 modes in the C-band and L-band.The simulated exchanged mode purities are greater than 85%.The phase masks were fabricated on a silicon substrate to facilitate the integration with optical systems,with an insert loss of less than 2.2 dB and mode crosstalk below-21 dB due primarily to machining inaccuracies and alignment errors.We carried out an optical communication experiment with 10 Gbit/s OOK and QPSK data transmission at the wavelength of 1550 nm and obtained excellent performance with the device.It paves the way for flexible data exchange as a building block in MDM optical communication networks.展开更多
基金supported by the Foundation for Development of Science and Technology of Shanghai (Grant No 022261002)
文摘A general numerical tool, based on thermal diffusion equation and full-vectorial eigen-mode equation, has been presented for the systematic analysis of graded index channel waveguide fabricated by ion exchange on Er^3＋ doped glass. Finite difference method with full-vectorial formulation （FV-FDM） is applied to solving the full-vectorial modes of graded index channel waveguide for the first time. The coupled difference equations based on magnetic fields in FV-FDM are derived from the Taylor series expansion and accurate formulation of boundary conditions. Hybrid nature of vectorial guided modes for both pump （980 nm） and signal light （1550 nm） are demonstrated by the simulation. Results show that the fabrication parameters of ion exchange, such as channel opening width and time ratio of second step to first step in ion exchange, have large influence on the properties of waveguide. By optimizing the fabrication parameters, maintenance of monomode for signal light and improvement of the gain dynamics can be achieved in Er^3＋ doped waveguide amplifier （EDWA） fabricated by ion exchange technique. This theoretical model is significant for the design and fabrication of EDWA with ion exchange technique. Furthermore, a single polarization EDWA, which operates at wavelength from 1528 nm to 1541 nm for HE polarization, is numerically designed.
文摘This paper presents an energy analysis of a counter-flow plate heat exchanger operating in stationary mode. The exchanger comprises a rectangular plate of which we vary the heat transfer surface (by fixing its width and varying its length) and analyze the evolution of some parameters as a function of this heat transfer surface. The parameters to be analyzed are the NTU (number of transfer units), the effectiveness, the temperatures of both primary and secondary fluids and the heat flux. The analysis carried out will help understand the behavior of the counter-flow plate heat exchanger operating in stationary mode. Then, the heat transfer surface of the exchanger is determined for the sizing of a counter-flow plate heat exchanger intended to produce hot air for drying. That plate heat exchanger uses water vapor heated by geothermal energy as a primary fluid and atmospheric air as a secondary fluid. The products to be dried are onions with a mass flow of water to be evacuated of 100 kg/h.
基金supported by the Fundamental Research Foundation of Shanxi Province,China(Grant No.2013021010-3)the Natural Science Foundation of Shanxi Normal University,China(Grant No.872014)
文摘Based on the principle of minimal energy and the coherent rotation model, two types of the jump phenomena, complete and incomplete jump phenomenon, are proved to exist in the angular dependence of the exchange bias with noncollinear unidirectional and uniaxial anisotropies. It is found that the transition between complete and incomplete jump phenomena occurs on condition that the exchange-coupling constant exceeds a critical value. Additionally, two different modes of the magnetization rotation, the whole-plane rotation, and the half-plane rotation are present in the magnetization reversal process, and they are dependent on the direction of the external field. Furthermore, the equations of the critical angle, at which orientation the exchange bias field reaches a maximum value and the coercivity disappears, are also derived in this paper. The numerical calculations in this paper are consistent with the relevant experimental observations, indicating that our method to study the angular dependence of the exchange bias as well as the magnetization reversal behaviors is valid. Our discussion about the jump phenomenon, the critical angle, and the modes of the magnetization reversal can explain the observed differences in results between different experiments.
基金a preliminary research on BISU’s innovative cultural exchange mode between China and Japan:the project conclusion with the focus of cooking classroom.The approval number of the project is C3008190210the evolution and enlightenment of Japan’s pension problem from traditional to modern society.The approval number of the project is 18BSS033.
文摘This paper investigates the characteristics and evolution process of Sino-Japanese diet culture exchange in each historical period,analyzes the possible impact of globalization on Sino-Japanese diet culture exchange,and discusses the development direction of innovative mode of Sino-Japanese diet culture exchange under the background of globalization.
基金supported by the Guangdong Major Project of Basic Research(No.2020B0301030009)the National Natural Science Foundation of China(Nos.U23A20372,61935013,62105215,and 62275171)+3 种基金the Shenzhen Peacock Plan(No.KQTD20170330110444030)the Stable Support Project of Shenzhen(Nos.20220810152651001 and 20220811103827001)the Natural Science Foundation of GuangdongProvince(Nos.2020A1515011185and 2022A1515011642)Shenzhen University(No.2019075)。
文摘Data exchange between different mode channels is essential in the optical communication network with mode-division multiplexing(MDM).However,there are challenges in realizing mode exchange with low insert loss,low mode crosstalk,and high integration.Here,we designed and fabricated a mode exchange device based on multiplane light conversion(MPLC),which supports the transmission of LP01,LP11a,LP11b,and LP21 modes in the C-band and L-band.The simulated exchanged mode purities are greater than 85%.The phase masks were fabricated on a silicon substrate to facilitate the integration with optical systems,with an insert loss of less than 2.2 dB and mode crosstalk below-21 dB due primarily to machining inaccuracies and alignment errors.We carried out an optical communication experiment with 10 Gbit/s OOK and QPSK data transmission at the wavelength of 1550 nm and obtained excellent performance with the device.It paves the way for flexible data exchange as a building block in MDM optical communication networks.
