The present study introduced a new motion analysis method for total hip arthroplasty (THA). A motion simulation module of THA was designed and developed, which can simulate the THA’s implantation condition and motion...The present study introduced a new motion analysis method for total hip arthroplasty (THA). A motion simulation module of THA was designed and developed, which can simulate the THA’s implantation condition and motion and detect the theoretic range of motion (ROM) before the prosthetic component impingement happens.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
We extend the third perturbation theory to study the polarization control behavior of the intermediate state absorption in Nd^（3＋）ions. The results show that coherent interference can occur between the single-photo...We extend the third perturbation theory to study the polarization control behavior of the intermediate state absorption in Nd^（3＋）ions. The results show that coherent interference can occur between the single-photon and three-photon excitation pathways, and depends on the central frequency of the femtosecond laser field. Moreover,single-photon and three-photon absorptions have different polarization control efficiencies, and the relative weight of three-photon absorption in the whole excitation processes can increase with increasing the laser intensity.Therefore, the enhancement or suppression of the intermediate state absorption can be realized and manipulated by properly designing the intensity and central frequency of the polarization modulated femtosecond laser field.This research can not only enrich theoretical research methods for the up-conversion luminescence manipulation of rare-earth ions, but also can provide a clear physical picture for understanding and controlling multi-photon absorption in a multiple energy level system.展开更多
A simplified simulation method based on the FDTD technique that can handle active devices is proposed. This method well suits the electrical crosstalk analysis of multi-channel integrated, opto-electronic mixed module...A simplified simulation method based on the FDTD technique that can handle active devices is proposed. This method well suits the electrical crosstalk analysis of multi-channel integrated, opto-electronic mixed modules. We apply this method to an 8-channel integrated super-compact high-sensitivity optical module. The results show good agreement between simulations and measurements.展开更多
Fault characteristic gas analysis is one of the important methods for monitoring the operating status of power equipment.This study presents the construction of a simulation model for a hollow-core photonic crystal fi...Fault characteristic gas analysis is one of the important methods for monitoring the operating status of power equipment.This study presents the construction of a simulation model for a hollow-core photonic crystal fibre(HC-PCF)-based photothermal spectroscopy gas detection system.The relationship between the phase change of the probe beam and the acetylene concen-tration,pump power,ambient temperature and the modulation frequency is examined.It is achieved by simulating the wavelength modulation of the pump beam and the phase change of the probe beam.The findings demonstrate that there is a linear positive correlation between the pump power and the amplitude of the phase change of the probe beam and the acetylene concentration.For example,acetylene concentration grew from 1 to 10,000 ppm,whereas phase change amplitude increased from 4.71×10^(−4) to 3.70 rad.The pump power grew from 7 to 2000 mW,whereas phase change amplitude increased from 3.73×10^(−4) to 1.01×10^(−1) rad.The phase change of the probe beam is non-linearly and negatively correlated with the ambient temperature.The ambient temperature decreases from 373.15 to 173.15 K,and phase change amplitude increases from 5.05×10^(−3) to 2.15×10^(−2) rad,an enhancement of 4.26 times.The modulation frequency is needed to balance the thermal conduction process in the HC-PCF.In the 1-100 Hz range,the amplitude of the phase change is stable and almost independent of the modulation frequency.In the 100-40,000 Hz range,the amplitude of the phase change decreases rapidly with the increase of the modulation frequency.The results of the paper provide a reference for constructing the HC-PCF-based photothermal spectroscopy gas detection system.展开更多
基金supported by the National Natural Science Foundation of China(No. 30810103908)the Science Foundation of Shanghai(No.09441900300)the National Basic Research Program(973)of China(No.2011CB711000)
文摘The present study introduced a new motion analysis method for total hip arthroplasty (THA). A motion simulation module of THA was designed and developed, which can simulate the THA’s implantation condition and motion and detect the theoretic range of motion (ROM) before the prosthetic component impingement happens.
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Supported by the National Natural Science Foundation of China under Grant Nos 51132004,11474096,11604199,U1704145 and 11747101the Science and Technology Commission of Shanghai Municipality under Grant No 14JC1401500+1 种基金the Henan Provincial Natural Science Foundation of China under Grant No 182102210117the Higher Education Key Program of He’nan Province of China under Grant Nos 17A140025 and 16A140030
文摘We extend the third perturbation theory to study the polarization control behavior of the intermediate state absorption in Nd^（3＋）ions. The results show that coherent interference can occur between the single-photon and three-photon excitation pathways, and depends on the central frequency of the femtosecond laser field. Moreover,single-photon and three-photon absorptions have different polarization control efficiencies, and the relative weight of three-photon absorption in the whole excitation processes can increase with increasing the laser intensity.Therefore, the enhancement or suppression of the intermediate state absorption can be realized and manipulated by properly designing the intensity and central frequency of the polarization modulated femtosecond laser field.This research can not only enrich theoretical research methods for the up-conversion luminescence manipulation of rare-earth ions, but also can provide a clear physical picture for understanding and controlling multi-photon absorption in a multiple energy level system.
文摘A simplified simulation method based on the FDTD technique that can handle active devices is proposed. This method well suits the electrical crosstalk analysis of multi-channel integrated, opto-electronic mixed modules. We apply this method to an 8-channel integrated super-compact high-sensitivity optical module. The results show good agreement between simulations and measurements.
基金supported by National Natural Science Foundation of China,Grant No.52277161.
文摘Fault characteristic gas analysis is one of the important methods for monitoring the operating status of power equipment.This study presents the construction of a simulation model for a hollow-core photonic crystal fibre(HC-PCF)-based photothermal spectroscopy gas detection system.The relationship between the phase change of the probe beam and the acetylene concen-tration,pump power,ambient temperature and the modulation frequency is examined.It is achieved by simulating the wavelength modulation of the pump beam and the phase change of the probe beam.The findings demonstrate that there is a linear positive correlation between the pump power and the amplitude of the phase change of the probe beam and the acetylene concentration.For example,acetylene concentration grew from 1 to 10,000 ppm,whereas phase change amplitude increased from 4.71×10^(−4) to 3.70 rad.The pump power grew from 7 to 2000 mW,whereas phase change amplitude increased from 3.73×10^(−4) to 1.01×10^(−1) rad.The phase change of the probe beam is non-linearly and negatively correlated with the ambient temperature.The ambient temperature decreases from 373.15 to 173.15 K,and phase change amplitude increases from 5.05×10^(−3) to 2.15×10^(−2) rad,an enhancement of 4.26 times.The modulation frequency is needed to balance the thermal conduction process in the HC-PCF.In the 1-100 Hz range,the amplitude of the phase change is stable and almost independent of the modulation frequency.In the 100-40,000 Hz range,the amplitude of the phase change decreases rapidly with the increase of the modulation frequency.The results of the paper provide a reference for constructing the HC-PCF-based photothermal spectroscopy gas detection system.
