A female patient at the age of 17 received dilator implant on the right part of her face to prepare skin flap for her facial scar.The skin flap was in good conditions before scar cutting,but showed poor blood circulat...A female patient at the age of 17 received dilator implant on the right part of her face to prepare skin flap for her facial scar.The skin flap was in good conditions before scar cutting,but showed poor blood circulation after being transferred.Hyperbaric oxygen therapy was given at 0.2 MPa(2ATA) in double pure oxygen cabins for 90 min every day for 10 d.The skin flap showed in sound viability and sound blood circulation after the treatment.Hyperbaric oxygen therapy can be used to treat blood circulation disorder in transferred skin flap.展开更多
Photodynamic therapy (PDT) is an established endoscopic technique for ablating Barrett's esophagus with high-grade dysplasia or early-stage intraepithelial neoplasia. The most common clinically significant adverse...Photodynamic therapy (PDT) is an established endoscopic technique for ablating Barrett's esophagus with high-grade dysplasia or early-stage intraepithelial neoplasia. The most common clinically significant adverse effect of PDT is esophageal stricture formation. The strictures are usually superficial and might be dilated effectively with standard endoscopic accessories, such as endoscope balloon or Savary dilators. However, multiple dilations might be required to achieve stricture resolution in some cases. We report the case of stricture that recurred after dilation with a bougie, which was completely relieved by a self-expandable metal stent.展开更多
The multi-dimensional time-domain computational fluid dynamics(CFD) approach is extended to calculate the acoustic attenuation performance of water-filled piping silencers. Transmission loss predictions from the time-...The multi-dimensional time-domain computational fluid dynamics(CFD) approach is extended to calculate the acoustic attenuation performance of water-filled piping silencers. Transmission loss predictions from the time-domain CFD approach and the frequency-domain finite element method(FEM) agree well with each other for the dual expansion chamber silencer, straight-through and cross-flow perforated tube silencers without flow. Then, the time-domain CFD approach is used to investigate the effect of flow on the acoustic attenuation characteristics of perforated tube silencers. The numerical predictions demonstrate that the mean flow increases the transmission loss, especially at higher frequencies, and shifts the transmission loss curve to lower frequencies.展开更多
In order to meet the precision requirements and tracking performance of the continuous rotary motor electro-hydraulic servo system under unknown strong non-linear and uncertain strong disturbance factors,such as dynam...In order to meet the precision requirements and tracking performance of the continuous rotary motor electro-hydraulic servo system under unknown strong non-linear and uncertain strong disturbance factors,such as dynamic uncertainty and parameter perturbation,an improved active disturbance rejection control(ADRC)strategy was proposed.The state space model of the fifth order closed-loop system was established based on the principle of valve-controlled hydraulic motor.Then the three parts of ADRC were improved by parameter perturbation and external disturbance;the fast tracking differentiator was introduced into linear and non-linear combinations;the nonlinear state error feedback was proposed using synovial control;the extended state observer was determined by nonlinear compensation.In addition,the grey wolf algorithm was used to set the parameters of the three parts.The simulation and experimental results show that the improved ADRC can realize the system frequency 12 Hz when the tracking accuracy and response speed meet the requirements of double ten indexes,which lay foundation for the motor application.展开更多
文摘A female patient at the age of 17 received dilator implant on the right part of her face to prepare skin flap for her facial scar.The skin flap was in good conditions before scar cutting,but showed poor blood circulation after being transferred.Hyperbaric oxygen therapy was given at 0.2 MPa(2ATA) in double pure oxygen cabins for 90 min every day for 10 d.The skin flap showed in sound viability and sound blood circulation after the treatment.Hyperbaric oxygen therapy can be used to treat blood circulation disorder in transferred skin flap.
文摘Photodynamic therapy (PDT) is an established endoscopic technique for ablating Barrett's esophagus with high-grade dysplasia or early-stage intraepithelial neoplasia. The most common clinically significant adverse effect of PDT is esophageal stricture formation. The strictures are usually superficial and might be dilated effectively with standard endoscopic accessories, such as endoscope balloon or Savary dilators. However, multiple dilations might be required to achieve stricture resolution in some cases. We report the case of stricture that recurred after dilation with a bougie, which was completely relieved by a self-expandable metal stent.
基金Project(11174065)supported by the National Natural Science Foundation of China
文摘The multi-dimensional time-domain computational fluid dynamics(CFD) approach is extended to calculate the acoustic attenuation performance of water-filled piping silencers. Transmission loss predictions from the time-domain CFD approach and the frequency-domain finite element method(FEM) agree well with each other for the dual expansion chamber silencer, straight-through and cross-flow perforated tube silencers without flow. Then, the time-domain CFD approach is used to investigate the effect of flow on the acoustic attenuation characteristics of perforated tube silencers. The numerical predictions demonstrate that the mean flow increases the transmission loss, especially at higher frequencies, and shifts the transmission loss curve to lower frequencies.
基金Project(51975164)supported by the National Natural Science Foundation of ChinaProject(2019-KYYWF-0205)supported by the Fundamental Research Foundation for Universities of Heilongjiang Province,China。
文摘In order to meet the precision requirements and tracking performance of the continuous rotary motor electro-hydraulic servo system under unknown strong non-linear and uncertain strong disturbance factors,such as dynamic uncertainty and parameter perturbation,an improved active disturbance rejection control(ADRC)strategy was proposed.The state space model of the fifth order closed-loop system was established based on the principle of valve-controlled hydraulic motor.Then the three parts of ADRC were improved by parameter perturbation and external disturbance;the fast tracking differentiator was introduced into linear and non-linear combinations;the nonlinear state error feedback was proposed using synovial control;the extended state observer was determined by nonlinear compensation.In addition,the grey wolf algorithm was used to set the parameters of the three parts.The simulation and experimental results show that the improved ADRC can realize the system frequency 12 Hz when the tracking accuracy and response speed meet the requirements of double ten indexes,which lay foundation for the motor application.
