This paper presents the design of a novel oscillometry device for the measurement of respiratory mechanics based on piezoelectric bimorph actuator technology. To predict performance for measurement of human respirator...This paper presents the design of a novel oscillometry device for the measurement of respiratory mechanics based on piezoelectric bimorph actuator technology. To predict performance for measurement of human respiratory mechanics, a dynamic model was developed based on a bimorph piezoelectric actuator driving a linear resistance mesh screen including subject’s respiratory impedance loads, and realistic breathing noise. Model performance was also validated in a prototype device. We found that while breathing noise substantially lowered SNR, the model could produce sufficient pressure and flow for acceptable SNRs exceeding 35 dB, and accuracies exceeding 99%. Satisfactory accuracy could be achieved with load impedance errors less than 3%. Maintaining the air-gap around the oscillating mesh with a resistance against the leak greater than 0.38 cmH2O/L/s maintained good performance, with an acceptable 4 dB decrease to SNR. Moreover, this work provides multiple solutions to host higher amounts of noise and nonlinearities. These results indicate that the development of an accurate lightweight portable single frequency FOT device is feasible.展开更多
Optical traps have emerged as powerful tools for immobilizing and manipulating small particles in three dimensions.Fiber-based optical traps(FOTs)significantly simplify optical setup by creating trapping centers with ...Optical traps have emerged as powerful tools for immobilizing and manipulating small particles in three dimensions.Fiber-based optical traps(FOTs)significantly simplify optical setup by creating trapping centers with single or multiple pieces of optical fibers.In addition,they inherit the flexibility and robustness of fiber-optic systems.However,trapping 10-nm-diameter nanoparticles(NPs)using FOTs remains challenging.In this study,we model a coaxial waveguide that works in the optical regime and supports a transverse electromagnetic(TEM)-like mode for NP trapping.Single NPs at waveguide front-end break the symmetry of TEM-like guided mode and lead to high transmission efficiency at far-field,thereby strongly altering light momentum and inducing a large-scale back-action on the particle.We demonstrate,via finite-difference time-domain(FDTD)simulations,that this FOT allows for trapping single 10-nm-diameter NPs at low power.展开更多
文摘This paper presents the design of a novel oscillometry device for the measurement of respiratory mechanics based on piezoelectric bimorph actuator technology. To predict performance for measurement of human respiratory mechanics, a dynamic model was developed based on a bimorph piezoelectric actuator driving a linear resistance mesh screen including subject’s respiratory impedance loads, and realistic breathing noise. Model performance was also validated in a prototype device. We found that while breathing noise substantially lowered SNR, the model could produce sufficient pressure and flow for acceptable SNRs exceeding 35 dB, and accuracies exceeding 99%. Satisfactory accuracy could be achieved with load impedance errors less than 3%. Maintaining the air-gap around the oscillating mesh with a resistance against the leak greater than 0.38 cmH2O/L/s maintained good performance, with an acceptable 4 dB decrease to SNR. Moreover, this work provides multiple solutions to host higher amounts of noise and nonlinearities. These results indicate that the development of an accurate lightweight portable single frequency FOT device is feasible.
基金the National Natural Science Foundation of China(Grant No.11874164)the Innovation Fund of Wuhan National Laboratory for Optoelectronics and 1000 Talent Youth Program.The authors declare no conflicts of interest.
文摘Optical traps have emerged as powerful tools for immobilizing and manipulating small particles in three dimensions.Fiber-based optical traps(FOTs)significantly simplify optical setup by creating trapping centers with single or multiple pieces of optical fibers.In addition,they inherit the flexibility and robustness of fiber-optic systems.However,trapping 10-nm-diameter nanoparticles(NPs)using FOTs remains challenging.In this study,we model a coaxial waveguide that works in the optical regime and supports a transverse electromagnetic(TEM)-like mode for NP trapping.Single NPs at waveguide front-end break the symmetry of TEM-like guided mode and lead to high transmission efficiency at far-field,thereby strongly altering light momentum and inducing a large-scale back-action on the particle.We demonstrate,via finite-difference time-domain(FDTD)simulations,that this FOT allows for trapping single 10-nm-diameter NPs at low power.
