In this paper a new spherical actuator is designed and its advantages are compared to an existing spherical actuator, which function is limited by several design bottlenecks. First the output torque is too small. Seco...In this paper a new spherical actuator is designed and its advantages are compared to an existing spherical actuator, which function is limited by several design bottlenecks. First the output torque is too small. Second, the attitude is difficult to be accurately detected. The new three-dimen- sional magnetic pole array can solve these major problems. The new actuator features an outer rotor with multiple permanent magnet (PM) poles. Using an analytical solution and the finite element so- lution simulation, the feasibility of the approach is verified. A prototype was developed, tested, and experiments were conducted to obtain the practical value of the magnetic flux density.展开更多
The impedance of a solid state active phased array antenna varing with frequency and beam scanning scanning angle be matched with the solid state active matching network (SSAMN). In order to adjust and measure the rad...The impedance of a solid state active phased array antenna varing with frequency and beam scanning scanning angle be matched with the solid state active matching network (SSAMN). In order to adjust and measure the radar conveniently and Securely, it is necessary for the impedance of the simulator of the phased array antennas to be optimized.Having selected the PIN dilde controlling circuits and the circuit parameters optimized,the simulator circuit is determined through numerical computation The experiment is given in support of the simulation.展开更多
Thin-film lithium niobate electro-optical modulator will become the key device in the future optical communication,which has the advantages of high modulation rate,low half-wave voltage,large bandwidth,and easy integr...Thin-film lithium niobate electro-optical modulator will become the key device in the future optical communication,which has the advantages of high modulation rate,low half-wave voltage,large bandwidth,and easy integration compared with conventional bulk lithium niobate modulator.However,because the electrode gap of the lithium niobate film modulator is very narrow,when the microwave frequency gets higher,it leads to higher microwave loss,and the electro-optical performance of the modulator will be greatly reduced.Here,we propose a thin film lithium niobate electro-optic modulator with a bimetallic layer electrode structure to achieve microwave loss less than 8 dB/cm in the range of 200 GHz,exhibiting a voltage-length product of 1.1 V·cm and a 3 dB electro-optic bandwidth greater than 160 GHz.High-speed data transmission test has been performed,showing good performance.展开更多
In this study,a moored array optimization tool(MAOT)was developed and applied to the South China Sea(SCS)with a focus on three-dimensional temperature and salinity observations.Application of the MAOT involves two ste...In this study,a moored array optimization tool(MAOT)was developed and applied to the South China Sea(SCS)with a focus on three-dimensional temperature and salinity observations.Application of the MAOT involves two steps:(1)deriving a set of optimal arrays that are independent of each other for different variables at different depths based on an empirical orthogonal function method,and(2)consolidating these arrays using a K-center clustering algorithm.Compared with the assumed initial array consisting of 17 mooring sites located on a 3°×3°horizontal grid,the consolidated array improved the observing ability for three-dimensional temperature and salinity in the SCS with optimization efficiencies of 19.03%and 21.38%,respectively.Experiments with an increased number of moored sites showed that the most cost-effective option is a total of 20 moorings,improving the observing ability with optimization efficiencies up to 26.54%for temperature and 27.25%for salinity.The design of an objective array relies on the ocean phenomenon of interest and its spatial and temporal scales.In this study,we focus on basin-scale variations in temperature and salinity in the SCS,and thus our consolidated array may not well resolve mesoscale processes.The MAOT can be extended to include other variables and multi-scale variability and can be applied to other regions.展开更多
In order to couple the numerical simulation of a primary test stand driver with an optimal load design, a zero- dimensional wire array load model is designed based on the Saturn load model using PSPICE, which is an up...In order to couple the numerical simulation of a primary test stand driver with an optimal load design, a zero- dimensional wire array load model is designed based on the Saturn load model using PSPICE, which is an upgraded version of the Simulation Program with Integrated Circuit Emphasis (SPICE) designed by the ORCAD Corporation to perform circuit simulations. This paper calculates different load parameters and discusses factors influencing the driving current curve. With appropriate driving current curves chosen, further magneto-hydrodynamic calculations are carried out and discussed to provide the best results for experiments. The suggested optimal load parameters play an important role in experimental load design.展开更多
A global optimum location algorithm called Variable Step-Size Generalized Simulated Annealing(VSGSA) was applied to treating the data obtained by using an array of ion-electrodes in solutions containing mixtures of Na...A global optimum location algorithm called Variable Step-Size Generalized Simulated Annealing(VSGSA) was applied to treating the data obtained by using an array of ion-electrodes in solutions containing mixtures of Na+, K+, Ca2+. Unlike traditional optimization algorithms such as simplex procedure, VSGSA can be used to determine the model parameters without any priori information about the analytical system under investigation and overcome the disadvantage of simplex method which might converge to local extrema depending on the starting positions. The algorithm was applied to po-tentiometric determination of ions in mixture solutions.展开更多
The corrosion behavior of B10 copper-nickel alloy welded joints in seawater pipeline system was analyzed under local turbulence induced by weld residual height.The corrosion behavior was evaluated by array electrode t...The corrosion behavior of B10 copper-nickel alloy welded joints in seawater pipeline system was analyzed under local turbulence induced by weld residual height.The corrosion behavior was evaluated by array electrode technology,mor-phology and elemental characterization,and COMSOL Multiphysics simulation.The results provide a theoretical basis for the corrosion and leakage of B10 alloy in seawater pipeline under the action of turbulence.The results show that residual height-induced turbulence exhibits a significant effect on the corrosion behavior in different areas of welded joints in B10 alloy.Turbulence can damage some surfaces,causing polarity deflection followed by acceleration of corrosion,or it is easier to form a protective film to slow down corrosion.COMSOL Multiphysics results show that the shear rate and turbulent kinetic energy increase linearly with the increase in residual height and velocity.The corrosion behavior of alloy surface is influenced by controlling the mass transfer rate and surface state.展开更多
Numerical simulations of electrostatic precipitators featuring wire and spiked electrode designs were performed to determine particle behavior and separation efficiency. The applied-voltage mechanism that alters the f...Numerical simulations of electrostatic precipitators featuring wire and spiked electrode designs were performed to determine particle behavior and separation efficiency. The applied-voltage mechanism that alters the flow structure of particles through ionic winds and mean electric fields are revealed. Numeri- cal studies throughout the past years have shown these structures for channel and pipe configurations. However, less attention was given to field averaging for the ni,~r-product and electric field. Our study focuses on this averaging and illustrates relevant differences between multidimensional setups concern- ~ng these fields. Turbulence was modeled using the Reynolds-averaged Navier-Stokes equations with a second-order Reynolds-stress-model closure. A high three-dimensionality of the ionic wind-induced turbulence is presented. This leads to an increase in the submicron-particle precipitation rate. The results confirm the dependence of separation efficiency on particle density and permittivity, thereby showing the advantages of spiked wires compared with wire-plate setups used in electrostatic precipitators.展开更多
基金Supported by the National Key Basic Research and Development Program(973 Program)(2014CB046405)
文摘In this paper a new spherical actuator is designed and its advantages are compared to an existing spherical actuator, which function is limited by several design bottlenecks. First the output torque is too small. Second, the attitude is difficult to be accurately detected. The new three-dimen- sional magnetic pole array can solve these major problems. The new actuator features an outer rotor with multiple permanent magnet (PM) poles. Using an analytical solution and the finite element so- lution simulation, the feasibility of the approach is verified. A prototype was developed, tested, and experiments were conducted to obtain the practical value of the magnetic flux density.
文摘The impedance of a solid state active phased array antenna varing with frequency and beam scanning scanning angle be matched with the solid state active matching network (SSAMN). In order to adjust and measure the radar conveniently and Securely, it is necessary for the impedance of the simulator of the phased array antennas to be optimized.Having selected the PIN dilde controlling circuits and the circuit parameters optimized,the simulator circuit is determined through numerical computation The experiment is given in support of the simulation.
基金supported by the Self-deployment Project of Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China(No.2021ZZ104)the Fujian Province STS Project(Nos.2020T3002 and 2022T3012)。
文摘Thin-film lithium niobate electro-optical modulator will become the key device in the future optical communication,which has the advantages of high modulation rate,low half-wave voltage,large bandwidth,and easy integration compared with conventional bulk lithium niobate modulator.However,because the electrode gap of the lithium niobate film modulator is very narrow,when the microwave frequency gets higher,it leads to higher microwave loss,and the electro-optical performance of the modulator will be greatly reduced.Here,we propose a thin film lithium niobate electro-optic modulator with a bimetallic layer electrode structure to achieve microwave loss less than 8 dB/cm in the range of 200 GHz,exhibiting a voltage-length product of 1.1 V·cm and a 3 dB electro-optic bandwidth greater than 160 GHz.High-speed data transmission test has been performed,showing good performance.
基金The National Key Research and Development Program of China under contract No.2019YFC1408400the National Natural Science Foundation of China under contract No.41876029.
文摘In this study,a moored array optimization tool(MAOT)was developed and applied to the South China Sea(SCS)with a focus on three-dimensional temperature and salinity observations.Application of the MAOT involves two steps:(1)deriving a set of optimal arrays that are independent of each other for different variables at different depths based on an empirical orthogonal function method,and(2)consolidating these arrays using a K-center clustering algorithm.Compared with the assumed initial array consisting of 17 mooring sites located on a 3°×3°horizontal grid,the consolidated array improved the observing ability for three-dimensional temperature and salinity in the SCS with optimization efficiencies of 19.03%and 21.38%,respectively.Experiments with an increased number of moored sites showed that the most cost-effective option is a total of 20 moorings,improving the observing ability with optimization efficiencies up to 26.54%for temperature and 27.25%for salinity.The design of an objective array relies on the ocean phenomenon of interest and its spatial and temporal scales.In this study,we focus on basin-scale variations in temperature and salinity in the SCS,and thus our consolidated array may not well resolve mesoscale processes.The MAOT can be extended to include other variables and multi-scale variability and can be applied to other regions.
文摘In order to couple the numerical simulation of a primary test stand driver with an optimal load design, a zero- dimensional wire array load model is designed based on the Saturn load model using PSPICE, which is an upgraded version of the Simulation Program with Integrated Circuit Emphasis (SPICE) designed by the ORCAD Corporation to perform circuit simulations. This paper calculates different load parameters and discusses factors influencing the driving current curve. With appropriate driving current curves chosen, further magneto-hydrodynamic calculations are carried out and discussed to provide the best results for experiments. The suggested optimal load parameters play an important role in experimental load design.
基金Supported by the National Natural Science Foundation of China Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Academia Sinica
文摘A global optimum location algorithm called Variable Step-Size Generalized Simulated Annealing(VSGSA) was applied to treating the data obtained by using an array of ion-electrodes in solutions containing mixtures of Na+, K+, Ca2+. Unlike traditional optimization algorithms such as simplex procedure, VSGSA can be used to determine the model parameters without any priori information about the analytical system under investigation and overcome the disadvantage of simplex method which might converge to local extrema depending on the starting positions. The algorithm was applied to po-tentiometric determination of ions in mixture solutions.
基金support from the National Natural Science Foundation of China(Grant No.42176209)the Natural Science Foundation of Shandong Province(Grant No.ZR2021MD064)the Fundamental Research Funds for the Central Universities(Grant No.19CX05001A).
文摘The corrosion behavior of B10 copper-nickel alloy welded joints in seawater pipeline system was analyzed under local turbulence induced by weld residual height.The corrosion behavior was evaluated by array electrode technology,mor-phology and elemental characterization,and COMSOL Multiphysics simulation.The results provide a theoretical basis for the corrosion and leakage of B10 alloy in seawater pipeline under the action of turbulence.The results show that residual height-induced turbulence exhibits a significant effect on the corrosion behavior in different areas of welded joints in B10 alloy.Turbulence can damage some surfaces,causing polarity deflection followed by acceleration of corrosion,or it is easier to form a protective film to slow down corrosion.COMSOL Multiphysics results show that the shear rate and turbulent kinetic energy increase linearly with the increase in residual height and velocity.The corrosion behavior of alloy surface is influenced by controlling the mass transfer rate and surface state.
文摘Numerical simulations of electrostatic precipitators featuring wire and spiked electrode designs were performed to determine particle behavior and separation efficiency. The applied-voltage mechanism that alters the flow structure of particles through ionic winds and mean electric fields are revealed. Numeri- cal studies throughout the past years have shown these structures for channel and pipe configurations. However, less attention was given to field averaging for the ni,~r-product and electric field. Our study focuses on this averaging and illustrates relevant differences between multidimensional setups concern- ~ng these fields. Turbulence was modeled using the Reynolds-averaged Navier-Stokes equations with a second-order Reynolds-stress-model closure. A high three-dimensionality of the ionic wind-induced turbulence is presented. This leads to an increase in the submicron-particle precipitation rate. The results confirm the dependence of separation efficiency on particle density and permittivity, thereby showing the advantages of spiked wires compared with wire-plate setups used in electrostatic precipitators.