Aiming at the requirements of installation and work environment of metal-based fiber Bragg grating(FBG)sensor,a resistance spot welding method is presented.Firstly,the effect of welding parameters on welding quality i...Aiming at the requirements of installation and work environment of metal-based fiber Bragg grating(FBG)sensor,a resistance spot welding method is presented.Firstly,the effect of welding parameters on welding quality is discussed theoretically,and a suitable resistance spot welding method for the metal-based FBG sensor is proposed for the first time.Then through serial resistance spot welding tests,the feasibility and practicability of the method are verified,and optimal welding parameters for two different tested metals are obtained.Fatigue performance test validates FBG sensors installed by the proposed method with good fatigue properties and long-term stable measurement performance.The research results can provide technical guidance for engineering structure long-term safety monitoring.展开更多
The three-dimensional （3D） spot-scanning method is one of the most commonly used irradiation methods in charged particle beam radiotherapy. Generally, spot-scanning beam delivery utilizes the same size pencil beam t...The three-dimensional （3D） spot-scanning method is one of the most commonly used irradiation methods in charged particle beam radiotherapy. Generally, spot-scanning beam delivery utilizes the same size pencil beam to irradiate the tumor targets. Here we propose a spot-scanning beam delivery method with laterally- and longitudinally- mixed size pencil beams for heavy ion radiotherapy. This uses pencil beams with a bigger spot size in the lateral direction and wider mini spread-out Bragg peak （mini-SOBP） to irradiate the inner part of a target volume, and pencil beams with a smaller spot size in the lateral direction and narrower mini-SOBP to irradiate the peripheral part of the target volume. Instead of being controlled by the accelerator, the lateral size of the pencil beam was adjusted by inserting Ta scatterers in the beam delivery line. The longitudinal size Of the pencil beam （i.e. the width of the mini-SOBP） was adjusted by tilting mini ridge filters along the beam direction. The new spot-scanning beam delivery using carbon ions was investigated theoretically and compared with traditional spot-scanning beam delivery. Our results show that the new spot-scanning beam delivery has smaller lateral penumbra, steeper distal dose fall-off and the dose homogeneity （1-standard deviati^n/mean） in the target volume is better than 95%.展开更多
文摘Aiming at the requirements of installation and work environment of metal-based fiber Bragg grating(FBG)sensor,a resistance spot welding method is presented.Firstly,the effect of welding parameters on welding quality is discussed theoretically,and a suitable resistance spot welding method for the metal-based FBG sensor is proposed for the first time.Then through serial resistance spot welding tests,the feasibility and practicability of the method are verified,and optimal welding parameters for two different tested metals are obtained.Fatigue performance test validates FBG sensors installed by the proposed method with good fatigue properties and long-term stable measurement performance.The research results can provide technical guidance for engineering structure long-term safety monitoring.
基金Supported by Key Project of National Natural Science Foundation of China(U1232207)National Key Technology Support Program of the Ministry of Science and Technology of China(2015BAI01B11)+1 种基金National Key Research and Development Program of the Ministry of Science and Technology of China(2016YFC0904602)National Natural Science Foundation of China(11075191,11205217,11475231,11505249)
文摘The three-dimensional （3D） spot-scanning method is one of the most commonly used irradiation methods in charged particle beam radiotherapy. Generally, spot-scanning beam delivery utilizes the same size pencil beam to irradiate the tumor targets. Here we propose a spot-scanning beam delivery method with laterally- and longitudinally- mixed size pencil beams for heavy ion radiotherapy. This uses pencil beams with a bigger spot size in the lateral direction and wider mini spread-out Bragg peak （mini-SOBP） to irradiate the inner part of a target volume, and pencil beams with a smaller spot size in the lateral direction and narrower mini-SOBP to irradiate the peripheral part of the target volume. Instead of being controlled by the accelerator, the lateral size of the pencil beam was adjusted by inserting Ta scatterers in the beam delivery line. The longitudinal size Of the pencil beam （i.e. the width of the mini-SOBP） was adjusted by tilting mini ridge filters along the beam direction. The new spot-scanning beam delivery using carbon ions was investigated theoretically and compared with traditional spot-scanning beam delivery. Our results show that the new spot-scanning beam delivery has smaller lateral penumbra, steeper distal dose fall-off and the dose homogeneity （1-standard deviati^n/mean） in the target volume is better than 95%.
