近年来 ,通过影像学及眼眶的组织学研究证实在眼球赤道部附近有一个由胶原、弹性蛋白和平滑肌构成的 pulley。Pulley作为眼外肌的功能性起点决定着直肌作用力的方向和大小。本文就 pul ley的提出、组织结构、位置及对于非共同性斜视的...近年来 ,通过影像学及眼眶的组织学研究证实在眼球赤道部附近有一个由胶原、弹性蛋白和平滑肌构成的 pulley。Pulley作为眼外肌的功能性起点决定着直肌作用力的方向和大小。本文就 pul ley的提出、组织结构、位置及对于非共同性斜视的意义等作一综述。展开更多
According to the requirements of designing V-groove pulley transmission, an application development based on AutoCAD environment and using AutoLISP language is presented. As an example of effective solution for CAD ap...According to the requirements of designing V-groove pulley transmission, an application development based on AutoCAD environment and using AutoLISP language is presented. As an example of effective solution for CAD application, the CAD system for V-groove pulley transmission is established.展开更多
Due to the small models and compact structures,small harvesters have also caused problems such as poor threshing separation performance and large loss rates.In order to solve unstable cleaning effects of small harvest...Due to the small models and compact structures,small harvesters have also caused problems such as poor threshing separation performance and large loss rates.In order to solve unstable cleaning effects of small harvesters when they facing different working conditions,this study selected rice plants in hilly areas for the experiment.Tensile breaking force of different parts of mature rice was tested,which revealed the fracture mechanism of each part under the combined force.Inertial threshing method was used to simulate artificial plate bin and design three kinds of non-circular pulley variable speed transmission threshing mechanism.With the help of transient inertia force,threshing force was compensated.This paper tested the harvesting performance of the variable speed threshing device with the help of the harvest performance test.Results show when facing the small rice planting area,the T/2 variable speed threshing device has better cleaning performance,and also the harvest loss rate of T/4 variable speed threshing device is the lowest.Compared with the constant speed threshing device,the impurity content rate of the variable speed threshing device is increased by 0.64%to 8.76%;the loss rate is reduced by 0.45%to 1.79%,which provides a basis for the optimization design of small combine harvester in hilly areas.展开更多
To construct structurally stable sulfur cathode of Li-S battery with improved cycling performance,poly(acrylic acid)(PAA)crosslinked by cationic hydroxypropyl polyrotaxane(HPRN+)via dynamically reversible boronic este...To construct structurally stable sulfur cathode of Li-S battery with improved cycling performance,poly(acrylic acid)(PAA)crosslinked by cationic hydroxypropyl polyrotaxane(HPRN+)via dynamically reversible boronic ester bonds is synthesized and serves as the cathode binder.The smart polymer networks offer multifunction including buffering the volume change of the cathode during charge/discharge through the pulley effect of polyrotaxanes(PR),suppressing the shuttle effect by adsorption of polysulfide using the plentiful carboxyl,hydroxyl and quaternary ammonium cationic groups,and self-healing the micro-damages to ensure stable conduction pathways of the electrode.As a result,the Li-S batteries based on this novel multifunctional binder and simple commercial sulfur/carbon composites cathode exhibit excellent specific capacity and cycling stability.In particular,the specific capacity decay per cycle of the cell is only 0.064%along with high Coulombic efficiency after 550 cycles at 1.0 C,which is superior to most of the reported binders.Even under high sulfur loading,moreover,the cathode can deliver superior areal capacity and cycling stability.This proposed binder provides a new way for the design of high-stability sulfur cathodes.展开更多
Taking the MK7-3 of USA hydraulic buffer arresting device as the research subject,the dynamical model for the shipboard aircraft arresting system is established,and the magneto-rheological(MR) damper is applied to pul...Taking the MK7-3 of USA hydraulic buffer arresting device as the research subject,the dynamical model for the shipboard aircraft arresting system is established,and the magneto-rheological(MR) damper is applied to pulley shock absorbers for shipboard aircraft block system.Due to the effect of the MR damper has not been known completely and so far MR damper model has not been defined,we use a set of characteristic test of the MR damper,through the process of parameters identification,to establish the dynamical model for the MR damper based on the Bingham plastic model.Then,the fuzzy control rules are designed,the buffer control for the pulley buffer of shipboard aircrafts is completed in touchdown moment based on MR technology. Compared with blocking device of hydraulic pulley buffer in the same condition,the simulations results show that the proposed MR pulley buffer can effectively recognize the impact energy for shipboard block system and reduce the pull peak of arresting cable.It improves significantly safety during landing of the air vehicles and lowers the risk of accidents.展开更多
In order to improve the elderly people's quality of life,supporting their walking behaviors is a promising technology.Therefore,based on one ultrasonic motor,a wire-driven series elastic mechanism for walking assi...In order to improve the elderly people's quality of life,supporting their walking behaviors is a promising technology.Therefore,based on one ultrasonic motor,a wire-driven series elastic mechanism for walking assistive system is proposed and investigated in this research.In contrast to tradition,it innovatively utilizes an ultrasonic motor and a wire-driven series elastic mechanism to achieve superior system performances in aspects of simple structure,high torque/weight ratio,quiet operation,quick response,favorable electromagnetic compatibility,strong shock resistance,better safety,and accurately stable force control.The proposed device is mainly composed of an ultrasonic motor,a linear spring,a steel wire,four pulleys and one rotating part.To overcome the ultrasonic motor's insufficient output torque,a steel wire and pulleys are smartly combined to directly magnify the torque instead of using a conventional gear reducer.Among the pulleys,there is one tailored pulley playing an important role to keep the reduction ratio as 4.5 constantly.Meanwhile,the prototype is manufactured and its actual performance is verified by experimental results.In a one-second operating cycle,it only takes 86 ms for this mechanism to output an assistive torque of 1.6 N·m.At this torque,the ultrasonic motor's speed is around 4.1 rad/s.Moreover,experiments with different operation periods have been conducted for different application scenarios.This study provides a useful idea for the application of ultrasonic motor in walking assistance system.展开更多
文摘According to the requirements of designing V-groove pulley transmission, an application development based on AutoCAD environment and using AutoLISP language is presented. As an example of effective solution for CAD application, the CAD system for V-groove pulley transmission is established.
基金the National Natural Science Foundation of China(Grant No.52175235)Key Laboratory of Intelligent Equipment and Robotics for Agriculture of Zhejiang Province(Grant No.2023ZJZD2302)+1 种基金Jiangsu Province and Education Ministry Co-sponsored Synergistic Innovation Center of Modern Agricultural Equipment(Grant No.XTCX2007)Taizhou Science and Technology Support Plan(Agriculture)Project(TN202219).
文摘Due to the small models and compact structures,small harvesters have also caused problems such as poor threshing separation performance and large loss rates.In order to solve unstable cleaning effects of small harvesters when they facing different working conditions,this study selected rice plants in hilly areas for the experiment.Tensile breaking force of different parts of mature rice was tested,which revealed the fracture mechanism of each part under the combined force.Inertial threshing method was used to simulate artificial plate bin and design three kinds of non-circular pulley variable speed transmission threshing mechanism.With the help of transient inertia force,threshing force was compensated.This paper tested the harvesting performance of the variable speed threshing device with the help of the harvest performance test.Results show when facing the small rice planting area,the T/2 variable speed threshing device has better cleaning performance,and also the harvest loss rate of T/4 variable speed threshing device is the lowest.Compared with the constant speed threshing device,the impurity content rate of the variable speed threshing device is increased by 0.64%to 8.76%;the loss rate is reduced by 0.45%to 1.79%,which provides a basis for the optimization design of small combine harvester in hilly areas.
基金the National Natural Science Foundation of China(Nos.52033011,51873235 and 51973237)Natural Science Foundation of Guangdong Province,China(Nos.2019B1515120038 and 2021A1515010417)+1 种基金Science and Technology Planning Project of Guangdong Province(No.2020B010179001)Industry-University-Research Collaboration Project of Zhuhai City(No.ZH22017001200004PWC).
文摘To construct structurally stable sulfur cathode of Li-S battery with improved cycling performance,poly(acrylic acid)(PAA)crosslinked by cationic hydroxypropyl polyrotaxane(HPRN+)via dynamically reversible boronic ester bonds is synthesized and serves as the cathode binder.The smart polymer networks offer multifunction including buffering the volume change of the cathode during charge/discharge through the pulley effect of polyrotaxanes(PR),suppressing the shuttle effect by adsorption of polysulfide using the plentiful carboxyl,hydroxyl and quaternary ammonium cationic groups,and self-healing the micro-damages to ensure stable conduction pathways of the electrode.As a result,the Li-S batteries based on this novel multifunctional binder and simple commercial sulfur/carbon composites cathode exhibit excellent specific capacity and cycling stability.In particular,the specific capacity decay per cycle of the cell is only 0.064%along with high Coulombic efficiency after 550 cycles at 1.0 C,which is superior to most of the reported binders.Even under high sulfur loading,moreover,the cathode can deliver superior areal capacity and cycling stability.This proposed binder provides a new way for the design of high-stability sulfur cathodes.
基金the National Natural Science Foundation of China(No.61074090)the Program for Liaoning Excellent Talents in University(No.LR2011005)the Aviation Industry Corporation of China Innovation Funds(No.cxy2011SH)
文摘Taking the MK7-3 of USA hydraulic buffer arresting device as the research subject,the dynamical model for the shipboard aircraft arresting system is established,and the magneto-rheological(MR) damper is applied to pulley shock absorbers for shipboard aircraft block system.Due to the effect of the MR damper has not been known completely and so far MR damper model has not been defined,we use a set of characteristic test of the MR damper,through the process of parameters identification,to establish the dynamical model for the MR damper based on the Bingham plastic model.Then,the fuzzy control rules are designed,the buffer control for the pulley buffer of shipboard aircrafts is completed in touchdown moment based on MR technology. Compared with blocking device of hydraulic pulley buffer in the same condition,the simulations results show that the proposed MR pulley buffer can effectively recognize the impact energy for shipboard block system and reduce the pull peak of arresting cable.It improves significantly safety during landing of the air vehicles and lowers the risk of accidents.
基金Supported by China Scholarship Council(Grant No.202006830033),Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)of China.
文摘In order to improve the elderly people's quality of life,supporting their walking behaviors is a promising technology.Therefore,based on one ultrasonic motor,a wire-driven series elastic mechanism for walking assistive system is proposed and investigated in this research.In contrast to tradition,it innovatively utilizes an ultrasonic motor and a wire-driven series elastic mechanism to achieve superior system performances in aspects of simple structure,high torque/weight ratio,quiet operation,quick response,favorable electromagnetic compatibility,strong shock resistance,better safety,and accurately stable force control.The proposed device is mainly composed of an ultrasonic motor,a linear spring,a steel wire,four pulleys and one rotating part.To overcome the ultrasonic motor's insufficient output torque,a steel wire and pulleys are smartly combined to directly magnify the torque instead of using a conventional gear reducer.Among the pulleys,there is one tailored pulley playing an important role to keep the reduction ratio as 4.5 constantly.Meanwhile,the prototype is manufactured and its actual performance is verified by experimental results.In a one-second operating cycle,it only takes 86 ms for this mechanism to output an assistive torque of 1.6 N·m.At this torque,the ultrasonic motor's speed is around 4.1 rad/s.Moreover,experiments with different operation periods have been conducted for different application scenarios.This study provides a useful idea for the application of ultrasonic motor in walking assistance system.
