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Radio frequency conditioning of an S-band accelerating structure prototype for compact proton therapy facility 被引量:3
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作者 Yu Zhang Wen-Cheng Fang +7 位作者 Xiao-Xia Huang Jian-Hao Tan Shao-Peng Zhong Cheng-Cheng Xiao Jun-Qiang Zhang Cheng Wang Yu-Qing Yang Zhen-Tang Zhao 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2021年第6期94-107,共14页
The development of a high-gradient accelerating structure is underway to construct a compact proton linear accelerator for cancer treatment.Extensive experiments and numerous studies are being conducted to develop com... The development of a high-gradient accelerating structure is underway to construct a compact proton linear accelerator for cancer treatment.Extensive experiments and numerous studies are being conducted to develop compact linear accelerators for proton therapy.Optimization of the electromagnetic and mechanical design has been performed to simplify the manufacturing process and reduce costs.A novel high-gradient structure with a low relativistic proton velocity(β),v/c=0.38,was designed,fabricated,and tested at high power.The first full-scale prototype was also successfully tested with high radio frequency(RF)power,a repetition rate of 50 Hz,and pulse length of 3μs to reach a high-gradient of 46 MV/m using a 50 MW S-band klystron power supply obtained from the Shanghai Soft X-ray Free Electron Laser Facility.This is the first high-power test in China,which is in line with the expected experimental goal.This study presents preliminary high-power testing of S-band standing wave accelerating structures with 11 cells.This work aims to verify the feasibility of using a high-gradient RF accelerating structure in compact proton therapy facilities.The cold test of the prototype cavity was completed in advance.Details of the high-power RF test setup,the process of RF conditioning,and the high-power results are described. 展开更多
关键词 s-band Standing wave(SW) High-gradient accelerating structure RF conditioning
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A compact X-band backward traveling-wave accelerating structure
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作者 Xian-Cai Lin Hao Zha +4 位作者 Jia-Ru Shi Qiang Gao Fang-Jun Hu Qing-Zhu Li Huai-Bi Chen 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第5期13-29,共17页
Very high-energy electrons(VHEEs)are potential candidates for FLASH radiotherapy for deep-seated tumors.We proposed a compact VHEE facility based on an X-band high-gradient high-power technique.In this study,we invest... Very high-energy electrons(VHEEs)are potential candidates for FLASH radiotherapy for deep-seated tumors.We proposed a compact VHEE facility based on an X-band high-gradient high-power technique.In this study,we investigated and realized the first X-band backward traveling-wave(BTW)accelerating structure as the buncher for a VHEE facility.A method for calculating the parameters of single cell from the field distribution was introduced to simplify the design of the BTW structure.Time-domain circuit equations were applied to calculate the transient beam parameters of the buncher in the unsteady state.A prototype of the BTW structure with a thermionic cathode-diode electron gun was designed,fabricated,and tested at high power at the Tsinghua X-band high-power test stand.The structure successfully operated with 5-MW microwave pulses from the pulse compressor and outputted electron bunches with an energy of 8 MeV and a pulsed current of 108 mA. 展开更多
关键词 Backward traveling-wave accelerating structure Equivalent circuit model High-power test Very high-energy electron radiotherapy
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Design,fabrication,and cold test of an S-band high-gradient accelerating structure for compact proton therapy facility 被引量:4
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作者 Yu Zhang Wen-Cheng Fang +4 位作者 Xiao-Xia Huang Jian-Hao Tan Cheng Wang Chao-Peng Wang Zhen-Tang Zhao 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2021年第4期38-48,共11页
An S-band high-gradient accelerating structure is designed for a proton therapy linear accelerator(linac)to accommodate the new development of compact,singleroom facilities and ultra-high dose rate(FLASH)radiotherapy.... An S-band high-gradient accelerating structure is designed for a proton therapy linear accelerator(linac)to accommodate the new development of compact,singleroom facilities and ultra-high dose rate(FLASH)radiotherapy.To optimize the design,an efficient optimization scheme is applied to improve the simulation efficiency.An S-band accelerating structure with 2856 MHz is designed with a low beta of 0.38,which is a difficult structure to achieve for a linac accelerating proton particles from 70 to 250 MeV,as a high gradient up to 50 MV/m is required.A special design involving a dual-feed coupler eliminates the dipole field effect.This paper presents all the details pertaining to the design,fabrication,and cold test results of the S-band high-gradient accelerating structure. 展开更多
关键词 s-band High gradient accelerating structure COMPACT Single-room facility Dual-feed coupler Cold test
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Design, fabrication, and testing of low-group-velocity S-band traveling-wave accelerating structure 被引量:1
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作者 Xian-Cai Lin Hao Zha +6 位作者 Jia-Ru Shi Liu-Yuan Zhou Yi-Fan Liang Jian Gao Qiang Gao Huai-Bi Chen Chuan-Xiang Tang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2022年第11期133-143,共11页
To implement the Tsinghua Thomson Scattering X-ray Source upgrade plan and the Very Compact Inverse Compton Scattering Gamma-ray Source (VIGAS) program, a new 1.5-m traveling-wave accelerating structure was designed t... To implement the Tsinghua Thomson Scattering X-ray Source upgrade plan and the Very Compact Inverse Compton Scattering Gamma-ray Source (VIGAS) program, a new 1.5-m traveling-wave accelerating structure was designed to replace the old 3-m SLAC-type structure with the aim of increasing the accelerating gradient from15 to 30 MV/m. The new type of structure works in the 3π/4 mode with a comparatively low group velocity varying from 0.007c to 0.003c to increase the accelerating gradient at a given power. An elliptical iris was employed to reduce the surface field enhancement. The filling process of the low-group-velocity structure was analyzed using a circuit model. After fabrication, the structure was precisely tuned using the non-contact tuning method, followed by detailed low-power radiofrequency measurements. The structure was first installed and utilized at a beamline for the terahertz experiment at Tsinghua University. After 120 h of conditioning, it is now operating at a gradient of 24.2 MV/m and a 20.7-MW input power, with the klystron operating at its full power. It is expected to generate an accelerating gradient of 30 MV/m when the klystron power is upgraded to 30 MW in the near future. 展开更多
关键词 Traveling-wave accelerating structure Cavity optimization Tuning method High-power test
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Aseismic performances of constrained damping lining structures made of rubber-sand-concrete
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作者 Xiancheng Mei Qian Sheng +4 位作者 Jian Chen Zhen Cui Jianhe Li Chuanqi Li Daniel Dias 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第5期1522-1537,共16页
Flexible damping technology considering aseismic materials and aseismic structures seems be a good solution for engineering structures.In this study,a constrained damping structure for underground tunnel lining,using ... Flexible damping technology considering aseismic materials and aseismic structures seems be a good solution for engineering structures.In this study,a constrained damping structure for underground tunnel lining,using a rubber-sand-concrete(RSC)as the aseismic material,is proposed.The aseismic performances of constrained damping structure were investigated by a series of hammer impact tests.The damping layer thickness and shape effects on the aseismic performance such as effective duration and acceleration amplitude of time-domain analysis,composite loss factor and damping ratio of the transfer function analysis,and total vibration level of octave spectrum analysis were discussed.The hammer impact tests revealed that the relationship between the aseismic performance and damping layer thickness was not linear,and that the hollow damping layer had a better aseismic performance than the flat damping layer one.The aseismic performances of constrained damping structure under different seismicity magnitudes and geological conditions were investigated.The effects of the peak ground acceleration(PGA)and tunnel overburden depth on the aseismic performances such as the maximum principal stress and equivalent plastic strain(PEEQ)were discussed.The numerical results show the constrained damping structure proposed in this paper has a good aseismic performance,with PGA in the range(0.2-1.2)g and tunnel overburden depth in the range of 0-300 m. 展开更多
关键词 Constrained damping structure Aseismic performance Hammer impact tests Damping layer Peak ground acceleration Overburden depth
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Structure study of a dielectric laser accelerator with discrete translational symmetry
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作者 何阳帆 孙斌 +3 位作者 马铭江 李伟 崔志浩 赵宗清 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第11期413-418,共6页
The dielectric laser accelerator(DLA) is a promising technology for achieving high-gradient acceleration in a compact design. Its advantages include ease of cascading and an energy gain per unit distance which can exc... The dielectric laser accelerator(DLA) is a promising technology for achieving high-gradient acceleration in a compact design. Its advantages include ease of cascading and an energy gain per unit distance which can exceed that of conventional accelerators by two orders of magnitude. This paper establishes rules for efficient particle acceleration using dielectric structures based on basic equations, proposes a design principle for DLA structures with clear physical images and verifies the accuracy of the corresponding formula for energy gain. DLA structures with different specifications, materials and geometric shapes are constructed, and the achievable acceleration gradient is calculated. Our results demonstrate that effective acceleration can be achieved when the electric field sensed by particles in the acceleration cavity has zero frequency,which provides a powerful method for designing such devices. Furthermore, we demonstrate that the simplified formula for calculating energy gain presented in this paper can accurately determine the energy gain of particles during the design of acceleration structures using a dielectric accelerator. 展开更多
关键词 dielectric laser accelerator acceleration structure high-gradient accelerator
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Structure and material study of dielectric laser accelerators based on the inverse Cherenkov effect
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作者 孙斌 何阳帆 +5 位作者 罗若云 章太阳 周强 王少义 王度 赵宗清 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第9期250-254,共5页
Dielectric laser accelerators(DLAs)are considered promising candidates for on-chip particle accelerators that can achieve high acceleration gradients.This study explores various combinations of dielectric materials an... Dielectric laser accelerators(DLAs)are considered promising candidates for on-chip particle accelerators that can achieve high acceleration gradients.This study explores various combinations of dielectric materials and accelerated structures based on the inverse Cherenkov effect.The designs utilize conventional processing methods and laser parameters currently in use.We optimize the structural model to enhance the gradient of acceleration and the electron energy gain.To achieve higher acceleration gradients and energy gains,the selection of materials and structures should be based on the initial electron energy.Furthermore,we observed that the variation of the acceleration gradient of the material is different at different initial electron energies.These findings suggest that on-chip accelerators are feasible with the help of these structures and materials. 展开更多
关键词 dielectric laser accelerator high gradient accelerator inverse Cherenkov effect accelerated structure and material
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Design and calculation of a side-coupled accelerating structure 被引量:1
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作者 Ming-Xuan Liu Cong-Feng Wu +1 位作者 Yun-Gai Tang Gui-Rong Huang 《Nuclear Science and Techniques》 SCIE CAS CSCD 2017年第11期204-209,共6页
In this paper, we present the design and optimization of a side-coupled accelerating structure with an energy switch. The beam parameters are optimized, and the electric field asymmetry in the first cell is analyzed. ... In this paper, we present the design and optimization of a side-coupled accelerating structure with an energy switch. The beam parameters are optimized, and the electric field asymmetry in the first cell is analyzed. The new structure we designed has an improvement of 10 times in the accelerating field symmetry. Thermo-mechanical analysis is performed based on the electromagnetic results. The highest temperature is 72.5 ℃ at the nose cone, and the maximal deformation is 73 μm at the outer edge of the coupling cavity. 展开更多
关键词 Side-coupled accelerating structure Energy SWITCH BEAM dynamics Asymmetry THERMOMECHANICAL analysis
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Fabrication,tuning,and high-gradient testing of an X-band traveling-wave accelerating structure for VIGAS 被引量:2
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作者 Xian-Cai Lin Hao Zha +6 位作者 Jia-Ru Shi Qiang Gao Jia-Yang Liu Liu-Yuan Zhou Jian Gao Huai-Bi Chen Chuan-Xiang Tang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2022年第8期77-88,共12页
X-band high-gradient linear accelerators are a challenging and attractive technology for compact electron linear-accelerator facilities.The Very Compact Inverse Compton Scattering Gamma-ray Source(VIGAS)program at Tsi... X-band high-gradient linear accelerators are a challenging and attractive technology for compact electron linear-accelerator facilities.The Very Compact Inverse Compton Scattering Gamma-ray Source(VIGAS)program at Tsinghua University will utilize X-band high-gradient accelerating structures to boost the electron beam from 50 to 350 MeV over a short distance.A constant-impedance traveling-wave structure consisting of 72 cells working in the 2π/3 mode was designed and fabricated for this project.Precise tuning and detailed measurements were successfully applied to the structure.After 180 h of conditioning in the Tsinghua high-power test stand,the structure reached a target gradient of 80 MV/m.The breakdown rate versus gradient of this structure was measured and analyzed. 展开更多
关键词 Traveling-wave accelerating structure X-band high gradient Tuning method High-power test
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Structure of Relatively Accelerating Universe
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作者 Aloysius Sebastian 《International Journal of Astronomy and Astrophysics》 2014年第1期165-177,共13页
This article is about the structure of expanding universe. Here I am trying to create a structural model of universe according to my thoughts. Studies showthat universe is accelerating its rate of expansion. Here I am... This article is about the structure of expanding universe. Here I am trying to create a structural model of universe according to my thoughts. Studies showthat universe is accelerating its rate of expansion. Here I am trying to get some conclusions according to my thoughts. In my opinion, our universe is under a gravitational frame with all the matters in it. In this gravitational frame of universe we can consider our universe as a closed system and the empty space outside the frame as an open system. There are two possibilities we can find. One is relative motion of the objects inside the frame. By this way we can feel the universe is accelerating its expansion, but it is not. Another one is the vacuum energy absorption and negative pressure inside the frame. According to this thought, we can say that universe is accelerating and it can continue its motion at present conditions on it, even the force created by the big bang is decreasing. The other point is that, once the absorbed vacuum can create a negative pressure inside the frame, there is no need for the concept of dark energy in our universe [1]. According to this model, negative pressure inside the frame will be created by the absorbed vacuum from the space. So the existence of dark energy can be questioned. In this model, dark energy doesn't play any role in the expansion or rate of acceleration on the expansion of universe. So the dark energy doesn’t exist in this model. During the absorption of vacuum to the frame, it will increase the volume of the frame. It will create free spaces inside the frame to accommodate the vacuum inside the frame. The rest of the absorbed vacuum will move to the center of the frame by the action against gravity and the force created by the big bang. It will increase the density of the absorbed vacuum in the center and can create the negative pressure on the frame to pull it outside to the empty space. It will cause the acceleration on expansion of universe. These things are explained deeply in this article. And here it also explains the destiny of universe according to the frame and expansion of universe. 展开更多
关键词 structure of UNIVERSE Relatively accelerating UNIVERSE DOES DARK Energy Exist GRAVITATIONAL FRAME of UNIVERSE
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A Method for Reducing Noise Radiated from Structures with Vibration Absorbers by Using an Accelerated Neural Network 被引量:2
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作者 李连进 葛为民 《Transactions of Tianjin University》 EI CAS 2004年第1期9-15,共7页
A method for reducing noise radiated from structures by vibration absorbers is presented. Since usual design method for the absorbers is invalid for noise reduction, the peaks of noise power in the frequency domain as... A method for reducing noise radiated from structures by vibration absorbers is presented. Since usual design method for the absorbers is invalid for noise reduction, the peaks of noise power in the frequency domain as cost functions are applied. Hence, the equations for obtaining optimal parameters of the absorbers become nonlinear expressions. To have the parameters, an accelerated neural network procedure has been presented. Numerical calculations have been carried out for a plate type cantilever beam with a large width, and experimental tests have been also performed for the same beam. It is clarified that the present method is valid for reducing noise radiated from structures. As for the usual design method for the absorbers, model analysis has been given, so the number of absorbers should be the same as that of the considered modes. While the nonlinear problem can be dealt with by the present method, there is no restriction on the number of absorbers or the model number. 展开更多
关键词 structure vibration and noise control vibration absorber neural network accelerated neural network
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Design of 10 MeV electron linear accelerator for space environment simulation
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作者 Shu Zhang Cai Meng +6 位作者 Zu-Sheng Zhou Xiang He Jing-Ru Zhang Munawar Iqbal Zhan-Dong Zhang Bo-Wen Bai Yun-Long Chi 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第10期96-109,共14页
A compact 10 MeV S-band irradiation electron linear accelerator(linac)was developed to simulate electronic radiation in outer space and perform electron irradiation effect tests on spacecraft materials and devices.Acc... A compact 10 MeV S-band irradiation electron linear accelerator(linac)was developed to simulate electronic radiation in outer space and perform electron irradiation effect tests on spacecraft materials and devices.According to the requirements of space environment simulation,the electron beam energy can be adjusted in the range from 3.5 to 10 MeV,and the average current can be adjusted in the range from 0.1 to 1 mA.The linac should be capable of providing beam irradiation over a large area of 1 m^(2) with a uniformity greater than 90% and a scanning rate of 100 Hz.A novel method was applied to achieve such a high beam scanning rate by combining a kicker and a scanning magnet.Based on this requirement,a design for the10 MeV linac is proposed with an RF power pulse repetition rate of 500 Hz;it includes a thermal cathode electron gun,a bunching-accelerating section,and a scanning transport line.The detailed physical design and dynamic simulation results of the proposed 10 MeV electron linac are presented in this paper. 展开更多
关键词 Electron linac accelerating structure Beam scanning Beam homogenization Irradiation linac
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Design and implementation of dual-mode configurable memory architecture for CNN accelerator
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作者 山蕊 LI Xiaoshuo +1 位作者 GAO Xu HUO Ziqing 《High Technology Letters》 EI CAS 2024年第2期211-220,共10页
With the rapid development of deep learning algorithms,the computational complexity and functional diversity are increasing rapidly.However,the gap between high computational density and insufficient memory bandwidth ... With the rapid development of deep learning algorithms,the computational complexity and functional diversity are increasing rapidly.However,the gap between high computational density and insufficient memory bandwidth under the traditional von Neumann architecture is getting worse.Analyzing the algorithmic characteristics of convolutional neural network(CNN),it is found that the access characteristics of convolution(CONV)and fully connected(FC)operations are very different.Based on this feature,a dual-mode reronfigurable distributed memory architecture for CNN accelerator is designed.It can be configured in Bank mode or first input first output(FIFO)mode to accommodate the access needs of different operations.At the same time,a programmable memory control unit is designed,which can effectively control the dual-mode configurable distributed memory architecture by using customized special accessing instructions and reduce the data accessing delay.The proposed architecture is verified and tested by parallel implementation of some CNN algorithms.The experimental results show that the peak bandwidth can reach 13.44 GB·s^(-1)at an operating frequency of 120 MHz.This work can achieve 1.40,1.12,2.80 and 4.70 times the peak bandwidth compared with the existing work. 展开更多
关键词 distributed memory structure neural network accelerator reconfigurable arrayprocessor configurable memory structure
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PetroChina accelerating implementation of restructuring strategy; downstream business experiencing structural adjustment smoothly
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《China Oil & Gas》 CAS 2000年第4期20-21,共2页
关键词 PetroChina accelerating implementation of restructuring strategy downstream business experiencing structural adjustment smoothly
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Numerical simulation of projectiles with different structures penetrating multi-storey concrete target board 被引量:2
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作者 靳书云 朱倩倩 宁倩慧 《Journal of Measurement Science and Instrumentation》 CAS 2014年第3期1-5,共5页
Because the difference between the acceleration curve of traditional projectile structure and the measured accelera- tion curve is large, refining projectile structure is proposed. After setting up multi-storey concre... Because the difference between the acceleration curve of traditional projectile structure and the measured accelera- tion curve is large, refining projectile structure is proposed. After setting up multi-storey concrete target board penetrated by the projectiles with different structures, the simulations with traditional projectile structure and refining projectile structure are conducted using ANSYS/LS-DYNA, and two acceleration curves are obtained, respectively. And then the target experi- ment that the projectile penetrates eight-storey concrete board is conducted and the measured acceleration curves are ob- tained. By comparing the simulation acceleration curves with the measured acceleration curves, it can be concluded that the acceleration curve with refined projectile structure is closer to the measured curve. Therefore, the simulation curve with re- fined projectile structure is of higher reference value for simulation research. 展开更多
关键词 refined projectile structure LS-DYNA acceleration curve
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Optimization of the S-band side-coupled cavities for proton acceleration 被引量:3
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作者 Hao-Yun Li Xin-Miao Wan +2 位作者 Wei Chen Chen-Hui Shi Zhi-Hui Li 《Nuclear Science and Techniques》 SCIE CAS CSCD 2020年第3期1-9,共9页
The proton beam with energy around 100 MeV has seen wide applications in modern scientific research and in various fields.However,proton sources in China fall short for meeting experimental needs owing to the vast siz... The proton beam with energy around 100 MeV has seen wide applications in modern scientific research and in various fields.However,proton sources in China fall short for meeting experimental needs owing to the vast size and expensive traditional proton accelerators.The Institute of Nuclear Science and Technology of Sichuan University proposed to build a 3 GHz side-coupled cavity linac(SCL)for re-accelerating a 26 MeV proton beam extracted from a CS-30 cyclotron to 120 MeV.We carried out investigations into several vital factors of S-band SCL for proton acceleration,such as optimization of SCL cavity geometry,end cell tuning,and bridge coupler design.Results demonstrated that the effective shunt impedance per unit length ranged from 22.5 to 59.8 MX/m throughout the acceleration process,and the acceleration gradient changed from 11.5 to 15.7 MV/m when the maximum surface electric field was equivalent to Kilpatrick electric field.We obtained equivalent circuit parameters of the biperiodic structures and applied them to the end cell tuning;results of the theoretical analysis agreed well with the 3D simulation.We designed and optimized a bridge coupler based on the previously obtained biperiodic structure parameters,and the field distribution un-uniformness was\1.5%for a two-tank module.The radio frequency power distribution system of the linac was obtained based on the preliminary beam dynamics design. 展开更多
关键词 Proton beam Side-coupled cavity linac accelerating cavity Biperiodic structure Bridge coupler
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On time-step in structural seismic response analysis under ground displacement/acceleration 被引量:3
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作者 TianYuji~+ and Yang Qingshan~(++) School of Civil Engineering,Beijing Jiaotong University,Beijing 100044,China +Associate Professor ++Professor 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2009年第3期341-347,共7页
There are two models in use today to analyze structural responses when subjected to earthquake ground motions, the Displacement Input Model (DIM) and the Acceleration Input Model (AIM). The time steps used in dire... There are two models in use today to analyze structural responses when subjected to earthquake ground motions, the Displacement Input Model (DIM) and the Acceleration Input Model (AIM). The time steps used in direct integration methods for these models are analyzed to examine the suitability of DIM. Numerical results are presented and show that the time-step for DIM is about the same as for AIM, and achieves the same accuracy. This is contrary to previous research that reported that there are several sources of numerical errors associated with the direct application of earthquake displacement loading, and a very small time step is required to define the displacement record and to integrate the dynamic equilibrium equation. It is shown in this paper that DIM is as accurate and suitable as, if not more than, AIM for analyzing the response of a structure to uniformly distributed and spatially varying ground motions. 展开更多
关键词 integration time step multi-supported structure displacement input model acceleration input model spatially varying ground motions
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Investigation on seismic response of a three-stage soil slope supported by anchor frame structure 被引量:5
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作者 LIN Yu-liang LI Ying-xin +1 位作者 ZHAO Lian-heng YANG T Y 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第4期1290-1305,共16页
Based on a typical prototype of a soil slope in engineering practice, a numerical model of a three-stage soil slope supported by the anchor frame structure was established by means of FLAC3D code. The dynamic response... Based on a typical prototype of a soil slope in engineering practice, a numerical model of a three-stage soil slope supported by the anchor frame structure was established by means of FLAC3D code. The dynamic responses of three-stage soil slope and frame structure were studied by performing a series of bidirectional Wenchuan motions in terms of the failure mode of three-stage structure, the acceleration of soil slope, the displacement of frame structure, and the anchor stress of frame structure. The response accelerations in both horizontal and vertical directions are the most largely amplified at the slope top of each stage subjected to different shaking cases. The platforms among the stages reduce the amplification effect of response acceleration. The residual displacement of frame structure increases significantly as the intensity of shaking case increases. The frame structure at each stage presents a combined displacement mode consisting of a translation and a rotation around the vertex. The anchor stress of frame structure is mainly increased by the first intense pulse of Wenchuan seismic wave, and it is sensitive to the intensity of shaking case. The anchor stress of frame structure at the first stage is the most considerably enlarged by earthquake loading. 展开更多
关键词 three-stage soil slope anchor frame structure accelerATION DISPLACEMENT anchor stress
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Structure optimization of connection frames based on frequency sensitivity in macro-micro motion platforms 被引量:1
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作者 Lufan Zhang Xueli Li +3 位作者 Haihong Zhang Haixin Li Hu Li Jun Wu 《Nanotechnology and Precision Engineering》 EI CAS CSCD 2019年第1期40-47,共8页
High-performance connection frames are of great significance for ultra-high acceleration and ultra-precision positioning in macro-micro motion platforms. This paper first takes the connection frame as a research objec... High-performance connection frames are of great significance for ultra-high acceleration and ultra-precision positioning in macro-micro motion platforms. This paper first takes the connection frame as a research object,builds a finite element model(FEM) of the natural frequency of the frame, and then verifies the correctness of this model. The frequency sensitivity method is then used to perturb the structural parameters of the FEM of the connection frame, and the sensitivities of the first-order natural frequency and mass of the corresponding structural parameters are obtained by calculation and analysis. The design variables are also determined. The natural frequency is used as the optimization objective, and the design parameters and mass of the connection frame are constrained. The structural parameters of the connecting frame are obtained through optimization, and the model is built and verified by experiments. The results show that the first-order natural frequency of the connecting frame is effectively improved by the frequency sensitivity method, avoids resonance between the connecting frame and the voice coil motor, and realizes the lightweight design of the connection frame. This research provides a reliable basis for the stable operation and ultra-precision positioning of ultra-high acceleration macro-motion platforms. 展开更多
关键词 Ultra-high accelerATION CONNECTION FRAME NATURAL frequency Sensitivity structure optimization
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Design and validation of wireless acceleration sensor network for structural health monitoring 被引量:3
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作者 喻言 Ou Jinping 《High Technology Letters》 EI CAS 2006年第4期358-362,共5页
A wireless sensor network is proposed to monitor the acceleration of structures for the purpose of structural health monitoring of civil engineering structures. Using commercially available parts, several modules are ... A wireless sensor network is proposed to monitor the acceleration of structures for the purpose of structural health monitoring of civil engineering structures. Using commercially available parts, several modules are constructed and integrated into complete wireless sensors and base stations. The communication protocol is designed and the fusion arithmetic of the temperature and acceleration is embedded in the wireless sensor node so that the measured acceleration values are more accurate. Measures are adopted to finish energy optimization, which is an important issue for a wireless sensor network. The test is perfonned on an offshore platform model, and the experimental results are given to show the feasibility of the designed wireless sensor network . 展开更多
关键词 wireless sensor network structural health monitoring wireless sensor accelerATION energy optimization
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