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Milestone progress of the HEPS booster commissioning
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作者 Yue-Mei Peng Jian-She Cao +20 位作者 Jin-Hui Chen Hai-Yi Dong Ping He Yi Jiao Ling Kang Wen Kang Jian Li Jing-Yi Li Guo-Ping Lin Fang Liu Feng-Li Long Cai Meng Xin Qi Hua-Min Qu Yan-Feng Sui Sheng Wang Gang Xu Qiang Ye Jing Zhang Pei Zhang Wei-Min Pan 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第1期170-177,共8页
The high-energy photon source(HEPS)is the first fourth-generation synchrotron light source facility in China.The HEPS injector consists of a linear accelerator(Linac)and a full energy booster.The booster captures the ... The high-energy photon source(HEPS)is the first fourth-generation synchrotron light source facility in China.The HEPS injector consists of a linear accelerator(Linac)and a full energy booster.The booster captures the electron beam from the Linac and increases its energy to the value required for the storage ring.The full-energy beam could be injected to the storage ring directly or after“high-energy accumulation.”On November 17,2023,the key booster parameters successfully reached their corresponding target values.These milestone results were achieved based on numerous contributions,including nearly a decade of physical design,years of equipment development and installation,and months of beam commissioning.As measured at the extraction energy of 6 GeV,the averaged beam current and emittance reached 8.57 mA with 5 bunches and 30.37 nm rad with a single-bunch charge of 5.58 nC,compared with the corresponding target values of 6.6 mA and 35 nm rad,respectively.This paper presents the physical design,equipment development,installation,and commissioning process of the HEPS booster. 展开更多
关键词 High energy photon source BOOSTER Beam commissioning
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Science and Technology Commissioners Supporting High-Quality Development Project for Hundreds of Counties, Thousands of Towns, and Myriads of Villages in the Context of Rural Revitalization
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作者 Wenwen WEI Cuihong YANG Xiguang ZHU 《Asian Agricultural Research》 2024年第4期1-2,7,共3页
This paper discusses the important role of science and technology commissioners in the high-quality development of hundreds of counties,thousands of towns,and myriads of villages in the context of rural revitalization... This paper discusses the important role of science and technology commissioners in the high-quality development of hundreds of counties,thousands of towns,and myriads of villages in the context of rural revitalization,including building bridges,accelerating the transformation of achievements,promoting the value-added of the whole agricultural industry chain,and promoting the rapid development of rural industrial economy.It also discusses the working achievements of science and technology commissioners,in order to promote further development of rural revitalization in Guangdong Province. 展开更多
关键词 SCIENCE and TECHNOLOGY commissionERS Hundreds of counties thousands of TOWNS and myriads of VILLAGES SCIENCE and TECHNOLOGY support
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Design and commissioning of Brav measurement system for SC200 superconducting cyclotron 被引量:2
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作者 Man-Man Xu Yun-Tao Song +5 位作者 Gen Chen Yong-Hua Chen Kai-Zhong Ding Heng-Bo Li Jun Wang Jian Zhou 《Nuclear Science and Techniques》 SCIE CAS CSCD 2019年第6期57-62,共6页
The SC200 proton therapy superconducting cyclotron was developed by ASIPP (Hefei, China) and JINR (Dubna, Russia). A measurement system was designed to assess the average radial component of the magnetic field (Brav) ... The SC200 proton therapy superconducting cyclotron was developed by ASIPP (Hefei, China) and JINR (Dubna, Russia). A measurement system was designed to assess the average radial component of the magnetic field (Brav) with 15 search coils in the median plane. The winding differences of the search coils affect the measurement accuracy of the Brav. Based on the electromagnetic induction principle, to measure the Brav accurately, this paper focuses on the design and commissioning of the Brav measurement system. The preliminary results confirm that the system design is reasonable and suitable. After testing the search coil at different speeds, the optimal speed was determined as 2.5 mm/s. The relative error was approximately 0.1% under the maximum radial component of the magnetic field Br of 7 G. The measurement precision was up to 1.0×10^-3, which can provide the required measurement tolerance of 3–7 G for Br in the median plane. The commissioning of the Brav measurement system is an important step for Br measurement. It can check and adjust the asymmetry of the superconducting coils (SCs). 展开更多
关键词 SUPERCONDUCTING CYCLOTRON MAGNETIC FIELD MEASUREMENT system commissioning
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Building a New Socialist Countryside, Improving Commission and Agent System of “Village-level Accounting” 被引量:1
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作者 SHI Hong 《Journal of Northeast Agricultural University(English Edition)》 CAS 2006年第2期192-196,共5页
Rural finance is an issue concerned with rural people, improving rural financial management is important to close the relations of cadres and masses, maintain rural stability, and promote rural economic development. T... Rural finance is an issue concerned with rural people, improving rural financial management is important to close the relations of cadres and masses, maintain rural stability, and promote rural economic development. This article explained the main problems of village financial, the needs of introducing commission and agent system of "village-level accounting" for building a new socialist countryside, and the measures of improving commission and agent system of "village-level accounting". 展开更多
关键词 building a new socialist countryside rural financial management village-level accounting commission and agent system
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Design and Realization of Information System for Ningxia Sci-tech Special Commissioners
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作者 Changhong WANG 《Asian Agricultural Research》 2013年第6期133-135,共3页
The information system for Ningxia sci-tech special commissioners is an application system for realizing information collection,management and sharing in the entrepreneurial process of sci-tech special commissioners. ... The information system for Ningxia sci-tech special commissioners is an application system for realizing information collection,management and sharing in the entrepreneurial process of sci-tech special commissioners. This paper introduces overall design ideas,system functions,key technologies and realization methods of the information system for Ningxia sci-tech special commissioners. Completion of construction and coming into operation of the information system bring new breakthrough for information management and data statistics of sci-tech special commissioners. 展开更多
关键词 SCI-TECH SPECIAL commissionERS Infomration managem
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Baosteel's No.8 air separation unit and the practice of its system commissioning
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作者 ZHOU Chenhao CAI Lemin LI Zhengqiang 《Baosteel Technical Research》 CAS 2009年第3期23-26,共4页
This paper introduces the process flow, technical parameters and relevant features of Baosteel's No. 8 air separation unit (ASU) with a capacity of 60000m^3/h. It summarizes the commissioning work, which includes t... This paper introduces the process flow, technical parameters and relevant features of Baosteel's No. 8 air separation unit (ASU) with a capacity of 60000m^3/h. It summarizes the commissioning work, which includes the adjustment of the air compressor,the system's naked cooling,the precooling system and the operation adjustment. It also provides detailed analyses on some failures which occurred in the commissioning. Through the modification of the design and the interlocks, the tripping probability of the air compressor was greatly reduced. Through the heating of the system and the control of the water cooler's nitrogen flow,the overproof content of carbon dioxide and fluctuation of oxygen flow were avoided. Nitrogen-block in the argon system was eliminated by the precise control of the argon rectification flow and argon content. All these solutions have been proved to be effective by practice. 展开更多
关键词 air separation unit commissioning malfunction solution
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Commissioning of the TrueBeam STx 6 MV FFF Beam in the RayStation Treatment Planning System for SRS and SBRT Treatments
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作者 Yongsook C. Lee Yongbok Kim 《International Journal of Medical Physics, Clinical Engineering and Radiation Oncology》 2021年第1期16-37,共22页
<strong>Purpose:</strong> The purpose of this study is to provide technical information on commissioning the TrueBeam STx 6 MV flattening-filter free (FFF) beam in the RayStation treatment planning system ... <strong>Purpose:</strong> The purpose of this study is to provide technical information on commissioning the TrueBeam STx 6 MV flattening-filter free (FFF) beam in the RayStation treatment planning system (TPS) for stereotactic radiosurgery (SRS) and stereotactic body radiation therapy (SBRT) treatments. <strong>Methods:</strong> For beam modeling, percent depth dose curves, profiles and output factors for jaw-collimated fields and stereotactic cones as well as X-jaws transmission were measured. For multi-leaf collimator (MLC) modeling, MLC model parameters such as offset, gain, curvature, leaf tip width, tongue and groove and transmission were determined and output factors for MLC-collimated fields were measured. Absolute dose calibration was also performed. For beam model and MLC model validation, the American Association of Physicists in Medicine Task Group-119 plans, clinical SRS and SBRT plans and end-to-end testing were performed. <strong>Results:</strong> Beam characteristics of the 6 MV FFF beam agreed well with those in the literature. Validation results showed that our beam model and MLC model were acceptable for SRS and SBRT treatments. <strong>Conclusions:</strong> The technical information and dosimetric data provided in this study will be a useful reference for other clinics/institutions which will commission the same machine energy in the RayStation TPS. 展开更多
关键词 commissioning TrueBeam STx 6 MV Flattening-Filter Free (FFF) RayStation Stereotactic Radiosurgery (SRS) and Stereotactic Body Radiation Therapy (SBRT)
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Dataset for Beam Commissioning of the Vero4DRT System
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作者 Hideharu Miura Shuichi Ozawa +3 位作者 Shintaro Tsuda Masahiro Hayata Kiyoshi Yamada Yasushi Nagata 《International Journal of Medical Physics, Clinical Engineering and Radiation Oncology》 2016年第1期70-77,共8页
We present the results of measurements made using the Vero4DRT radiation therapy system, which is not yet widely used, to assist technicians in achieving reliable and safe radiotherapy to the patient. We measured perc... We present the results of measurements made using the Vero4DRT radiation therapy system, which is not yet widely used, to assist technicians in achieving reliable and safe radiotherapy to the patient. We measured percent depth dose, beam profile, and relative scatter factor under water and air conditions. The Vero4DRT system has a 150 × 150-mm fixed secondary collimator. Its multileaf collimator (MLC) design is a single-focus type, with 30 pairs of 5 mm thick leaves at the isocenter, and produces a maximum field size of 150 × 150 mm. Profile measurements were performed using a 0.016-cm<sup>3</sup> ionization chamber (PTW31016 pinpoint chamber;PTW, Freiburg GmbH Germany). A brass build-up cap was used for measurements obtained in air conditions. We present a useful measurement dataset for users of the Vero4DRT system. 展开更多
关键词 Vero4DRT Beam Characteristic commissioning
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Commissioning and operation of the cryostat for 3W1 SC wiggler
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作者 Miao-Fu Xu Xiang-Zhen Zhang +7 位作者 Rui Ye Jin-Can Wang Xiao-Juan Bian Yao Gao Min-Xian Li Fu-San Chen Xiao-Chen Yang Rui Ge 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第6期43-54,共12页
A 3W1 superconducting wiggler(SCW)with the pole gap of 68 mm was successfully tested and installed in a BEPC II storage ring in November,2019.The goal of zero liquid helium consumption was achieved,and the cryogenic s... A 3W1 superconducting wiggler(SCW)with the pole gap of 68 mm was successfully tested and installed in a BEPC II storage ring in November,2019.The goal of zero liquid helium consumption was achieved,and the cryogenic system exhibited a 12%residual cooling capacity(approximately 0.69 W@4.2 K).The 3W1-SCW was set to operate at 2.49 T and has been operating for more than seven months.Three instances of magnet quenching occurred during the normal operation.The evaporated helium gas can be recycled to the helium gas recycling system when the pressure in the helium tank is higher than the parameter value(the setpoint of the pressure value is 1.2 bara).The cryogenic system can be recovered within 4 h if sufficient liquid helium is available to inject into the cryostat. 展开更多
关键词 CRYOSTAT commissioning SC wiggler Synchrotron radiation
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Status of the Russian Human Rights Commissioner in the Russian State Power System and Practice of Human Rights Protection
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作者 刘秋岑 LU Mimi(Translated) 《The Journal of Human Rights》 2020年第6期837-853,共17页
In the 1990 s,Russia set up its system of human rights commissioners Although it does not have a long history,the system has been basically established,and it has played an important role in promoting the protection o... In the 1990 s,Russia set up its system of human rights commissioners Although it does not have a long history,the system has been basically established,and it has played an important role in promoting the protection of human rights and social development in Russia,as well as responding to unfriendly comments from the international community At the same time,Russia’s system of human rights commissioners remains insufficient in compulsory execution,the division of functions and powers,sources of funding,legal status,and operational efficiency These problems originate from deficient organizational design and external factors,including historical conditions,domestic politics,and international politics In the near future,Russia should strive to improve and develop its system of human rights commissioners under the cautious consideration of both internal and external factors. 展开更多
关键词 RUSSIA human rights commissioners protection of human rights
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基于科研诚信专员制度的图书馆科研诚信服务研究
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作者 钟源 吴振寰 《图书情报导刊》 2024年第5期9-14,共6页
高校科研诚信建设涉及主体众多,需要图书馆协同参与。从科研诚信专员制度入手,探讨了依托图书馆设立科研诚信专员岗位的必要性与可行性,并针对科研诚信问题发生前、中、后3个不同时期,探讨了图书馆进行科研诚信服务的途径;为进一步推动... 高校科研诚信建设涉及主体众多,需要图书馆协同参与。从科研诚信专员制度入手,探讨了依托图书馆设立科研诚信专员岗位的必要性与可行性,并针对科研诚信问题发生前、中、后3个不同时期,探讨了图书馆进行科研诚信服务的途径;为进一步推动图书馆依托科研诚信专员职能提供科研诚信服务,提出了应采取的措施:一是依托图书馆设立科研诚信专员岗位,完善相关制度;二是以科研诚信教育为基石,着重发挥图书馆咨询协调作用;三是主动探索学习,加强科研诚信专员培训。 展开更多
关键词 科研诚信专员制度 高校图书馆 科研诚信服务
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融入科技特派员制度的农林类专业实践教学体系建设——基于福建云霄杨桃科技小院案例的研究
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作者 曾芳芳 《中国现代教育装备》 2024年第3期154-156,共3页
在实施科技特派员制度的背景下,高校与科技特派员项目服务所在的乡村和企业经营主体签订实践教学基地建设合作协议,搭建农林类专业实践教学平台,是培养服务“三农”人才的重要渠道。在对福建云霄杨桃科技小院案例进行研究的基础上,着重... 在实施科技特派员制度的背景下,高校与科技特派员项目服务所在的乡村和企业经营主体签订实践教学基地建设合作协议,搭建农林类专业实践教学平台,是培养服务“三农”人才的重要渠道。在对福建云霄杨桃科技小院案例进行研究的基础上,着重从优化实践课程体系、改革实践教学内容、充实实践教学队伍、丰富实践教学形式、强化实践教学管理等方面对融入科技特派员制度的农林类专业实践教学体系建设进行了探索,并对实践成效进行了总结。 展开更多
关键词 科技特派员 农林类专业 实践教学体系
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科技特派员制度助力乡村人才振兴的路径探索
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作者 李菁菁 刘淑兰 《北京农业职业学院学报》 2024年第2期28-36,共9页
乡村人才振兴是实现农业现代化和乡村全面振兴的必然之举。然而目前在乡村人才使用过程中,存在“引才、育才、用才、留才”等方面的困境。科技特派员作为一支服务“三农”的人才队伍,能够提升乡村人才的反哺导向力、激发乡村人才的本土... 乡村人才振兴是实现农业现代化和乡村全面振兴的必然之举。然而目前在乡村人才使用过程中,存在“引才、育才、用才、留才”等方面的困境。科技特派员作为一支服务“三农”的人才队伍,能够提升乡村人才的反哺导向力、激发乡村人才的本土培育力、增强乡村人才平台的服务力以及提升乡村人才环境的吸引力。针对乡村人才振兴困境,可以从优化选聘机制、改进育人机制、健全服务机制、强化保障机制等方面探索科技特派员制度助力乡村人才振兴的路径。 展开更多
关键词 科技特派员制度 乡村振兴 乡村人才振兴
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Perceived stress among staff in Saudi Arabian dental colleges before and after an accreditation process: A cross-sectional study
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作者 Amal S Shaiban 《World Journal of Clinical Cases》 SCIE 2024年第4期758-765,共8页
BACKGROUND Accreditation processes are extensively employed to guarantee the quality of higher education institutions.However,this process can potentially generate a stressful atmosphere for staff,thus impacting their... BACKGROUND Accreditation processes are extensively employed to guarantee the quality of higher education institutions.However,this process can potentially generate a stressful atmosphere for staff,thus impacting their ability to perform optimally under pressure.AIM To examine the knowledge of the National Commission for Academic Assessment and Accreditation(NCAAA)and its effects on perceived stress among dental college staff before and after the program accreditation process.METHODS The present cross-sectional questionnaire-based study included 300 employees from three dental colleges.The same employees had to fill out the questionnaire 1 mo after the NCAAA process.RESULTS Approximately 51.33%of the included employees believed that NCAAA is essential to attract quality students to join the program before and after the program.A total of 44.67%felt that their stress was high before,and 31.33%had low stress levels before and after NCAAA.These findings were statistically significant(P≤0.05).CONCLUSION NCAAA raised the prestige of the institution and specific programmes and increased prospects to attract better students,staff,and money,according to the employees.In addition to their needed teaching,research,and other service responsibilities,this work requires a tremendous amount of faculty effort and may cause them stress. 展开更多
关键词 National commission for Academic Assessment and Accreditation Accreditation process Perceived stress STAFF
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我国科技特派员制度的CiteSpace可视化分析
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作者 姬淳睿 吴易雄 《科技与经济》 2024年第4期51-55,共5页
运用CiteSpace软件对1999—2024年539篇科技特派员制度相关研究文献进行可视化分析,绘制文献时序分布、发文作者、发文机构、关键词等知识图谱。结果显示,我国科技特派员制度研究分为初始起步、平稳推进和创新深化3个发展阶段;许多作者... 运用CiteSpace软件对1999—2024年539篇科技特派员制度相关研究文献进行可视化分析,绘制文献时序分布、发文作者、发文机构、关键词等知识图谱。结果显示,我国科技特派员制度研究分为初始起步、平稳推进和创新深化3个发展阶段;许多作者、团队之间合作关系还不够紧密;发文核心机构群尚未形成;研究热点聚焦于科技特派员制度的价值意蕴、运行机制、推广模式、政策分析、绩效评估和发展对策6个主题;研究前沿与我国“三农”发展密切关联。未来研究应丰富理论视角,构建科技特派员制度研究话语体系;进一步深化和拓展科技特派员制度相关经验和启示,补充地区适用性研究;紧跟新时代农业农村发展步伐,以满足当下农民实际需求为出发点和落脚点。 展开更多
关键词 科技特派员制度 CITESPACE 可视化分析
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Water Cooperation Priorities in the Lancang-Mekong River Basin Based on Cooperative Events Since the Mekong River Commission Establishment 被引量:9
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作者 FENG Yan WANG Wenling +2 位作者 SUMAN Daniel YU Shiwei HE Daming 《Chinese Geographical Science》 SCIE CSCD 2019年第1期58-69,共12页
The Lancang-Mekong River has attracted much attention from researchers, but the cooperation on water issues in this river basin has been limited, even after the establishment of the Mekong River Commission(MRC). Coope... The Lancang-Mekong River has attracted much attention from researchers, but the cooperation on water issues in this river basin has been limited, even after the establishment of the Mekong River Commission(MRC). Cooperation on water resources has been determined as one of the key priority areas in the Lancang-Mekong Cooperation Mechanism, but there are no details of targets. In order to establish the priorities of water cooperation under the mechanism, we adopted nine categories to classify the objectives of 87 water cooperation events based on the ‘Lancang-Mekong Water Cooperative Events Database' from 1995 to 2015. Based on the occurrence of cooperative events, cooperative objectives, cooperative scales, and approaches to cooperation, we conducted statistical, correlation, and text analyses. Our analyses indicated the following results: under the impact of economic conditions inside and outside the river basin, full cooperation appeared more difficult than bilateral and multilateral cooperation. Each of the partners adopted different preferences for cooperation targets. Cooperation with more definite objectives was easier to establish than cooperation with broader and more complex objectives. The potential objectives for water cooperation were navigation, hydropower, joint management, data sharing, flood control and water use. Because hydropower development is controversial, and because water cooperation is avoided by most existing regional cooperation mechanisms due to its complexity, we suggest the following priority areas for water cooperation in the Lancang-Mekong River Basin. 1) Navigation and flood control/drought relief are attractive objectives for all the riparian countries across the whole watershed. 2) Data sharing should be a priority for cooperation in the watershed due to its laying the foundation for the equitable and reasonable utilization of transboundary waters. 3) Hydropower is an objective best implemented mainly through bilateral cooperation, and on tributaries. 展开更多
关键词 water COOPERATION objective COOPERATIVE scale the Lancang-Mekong RIVER riparian country MEKONG RIVER commission
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Commission Strategy of the Auction House 被引量:5
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作者 WANG Yan~ 1,2 1. College of Economics, Fudan University, Shanghai 200433, China 2. School of Mathematics and Statistics, Wuhan University , Wuhan 430072, Hubei, China 《Wuhan University Journal of Natural Sciences》 EI CAS 2006年第3期507-510,共4页
In a SIPV model, when the commission proportion is not certain, but related with bargain price, generally, it is a linear function of the bargain price, this paper gives bidders' equilibrium bidding strategies in the... In a SIPV model, when the commission proportion is not certain, but related with bargain price, generally, it is a linear function of the bargain price, this paper gives bidders' equilibrium bidding strategies in the first-and secondprice auctions. We find that the equilibrium strategies in second-price auction are dominant strategies. For seller or auction house, whether the fixed proportion or the unfixed proportion is good is not only related with constant item and the linear coefficient of the linear function, the size of the fixed commission proportion, but also related with the value of the item auctioned. So, in the practical auctions, the seller and the auction house negotiated with each other to decide the commission rules for their own advantage. 展开更多
关键词 AUCTION commission proportion Bayesian equilibrium bidding strategy
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Beam dynamics,RF measurement,and commissioning of a CW heavy ion IH-DTL 被引量:2
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作者 Heng Du You-Jin Yuan +10 位作者 Zhong-Shan Li Zhi-Jun Wang Peng Jin Xiao-Ni Li Guo-Zhu Cai Wen-Wen Ge Guo-Feng Qu Yuan He Jia-Wen Xia Jian-Cheng Yang Xue-Jun Yin 《Nuclear Science and Techniques》 SCIE CAS CSCD 2018年第3期143-155,共13页
A 53.667 MHz CW(continuous-wave) heavy ion IH-DTL has been designed for the SSC-LINAC injector of HIRFL-CSR(Heavy Ions Research Facility at Lanzhou-Cooling Storage Ring). It accelerates ions with maximum mass-to-charg... A 53.667 MHz CW(continuous-wave) heavy ion IH-DTL has been designed for the SSC-LINAC injector of HIRFL-CSR(Heavy Ions Research Facility at Lanzhou-Cooling Storage Ring). It accelerates ions with maximum mass-to-charge ratio of 7.0 from 143 to 295 ke V/u. Low-power RF measurement of the IH-DTL1 has been taken to investigate the RF performance and the quality of the electric field distribution on the beam axis.The measured Q_0 value and the shunt impedance are 10,400 and 198 MX/m, respectively. The electric field distributions on and around the beam axis were evaluated and compared with the design value. By a new approach,the dipole field component is also estimated. The beam dynamics simulation using measured field distribution was presented in this paper. Based on the dynamics analysis in both transverse and longitudinal phase space, the field distribution can meet the design requirement. Finally, the RF conditioning and very first beam commissioning on the IH-DTL1 were finished. The beam test results agree well with the simulation results; what's more, the property of the variable output beam energy about the separated functions DTL was verified. 展开更多
关键词 LINAC RF MEASUREMENT BEAM DYNAMIC simulation commissioning
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RF tuning and beam commissioning of CW RFQ for China-ADS Injector-I 被引量:1
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作者 Hua Shi Huafu Ouyang +2 位作者 Shengchang Wang Ningchuang Zhou Gang Wu 《Nuclear Science and Techniques》 SCIE CAS CSCD 2018年第10期182-190,共9页
A 325-MHz continuous-wave(CW) four-vane radiofrequency quadrupole(RFQ) is employed in Injector-I of the China Accelerator-Driven Subcritical System. The radiofrequency tuning and beam commissioning were performed from... A 325-MHz continuous-wave(CW) four-vane radiofrequency quadrupole(RFQ) is employed in Injector-I of the China Accelerator-Driven Subcritical System. The radiofrequency tuning and beam commissioning were performed from January 2014 to January 2017. In a cold test, a stability study showed that the design of the segmented resonantly coupling and dipole stabilizer rods can shift the harmful quadrupole and dipole mode from the fundamental mode to above 2.6 MHz. We also found a simplified tuning method for the field unflatness, involving changing the inserted length of a few plug tuners. For achieving CW-beam commissioning, two full-size RFQs were constructed successively. The commissioning results indicate that the beam transmission rate decreased by approximately 3% as the normalized field unflatness decreased by 1%. A 10-MeV CW proton beam with an average beam current of 2.1 m A was achieved at the target of Injector-I, and the output beam energy of the RFQ was3.18 MeV. 展开更多
关键词 RFQ RF tuning CW-beam commissioning BEAM transmission rate
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Commissioning of TrueBeamTM Medical Linear Accelerator: Quantitative and Qualitative Dosimetric Analysis and Comparison of Flattening Filter (FF) and Flattening Filter Free (FFF) Beam 被引量:4
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作者 Ravindra Shende Gourav Gupta +1 位作者 Ganesh Patel Senthil Kumar 《International Journal of Medical Physics, Clinical Engineering and Radiation Oncology》 2016年第1期51-69,共19页
Motive of the study is to present quantitative and qualitative analysis and comparison of beam data measurement with FF (flattening filter) and FFF (flattening filter free) beam in a Varian TrueBeam<sup>TM</s... Motive of the study is to present quantitative and qualitative analysis and comparison of beam data measurement with FF (flattening filter) and FFF (flattening filter free) beam in a Varian TrueBeam<sup>TM</sup> Medical Linear Accelerator. Critique of beam characterization and evolution of dosimetric properties for 6 MV, 10 MV, 15 MV FF beam and 6 MVFFF, 10 MVFFF FFF beam has been carried out. We performed the comparison of photon beam data for two standard FF photon energy 6 MV, 10 MV verses 6 MVFFF, and 10 MVFFF FFF beam. Determination and comparison of parameter involved PDD (Percentage depth dose), Depth dose profile, Symmetry, Flatness, Quality index, Relative output factor, Penumbra, Transmission factor, DLG (Dosimetric leaf gap), in addition to degree of Un-flatness and off-axis ratio of FFF beam. Outcomes of presenting study had shown that change of various parameters such as Percentage depth dose curves, Shape of the depth dose profile, Transmission, Value of quality index and significant rise in surface dose for FFF in comparison with FF beam. Differences in the output factor at lower and higher field sizes for FFF beam compared to that of FF beam were found. The maximum output factor deviation between 6 MV and 6 MVFFF was found to be 4.55%, whereas in 10 MV and 10 MVFFF was 5.71%. Beam quality TPR20/10 for FFF beam was found to be lesser in magnitude, 5.42% for 6 MVFFF whereas 4.50% for 10 MVFFF compared to 6 MV and 10 MV FF beam respectively. Jaw transmission and interleaf leakage for FFF beam were found to be lesser than FF beam. Also DLG for FFF beam was found to be lesser in magnitude comparable to that of flattened beam. This study is mainly inclined towards evaluation and comparison of the FF and FFF beam. It has been observed that, the outcome of a commissioning beam data generation fully complies with vendor specification and published literature. 展开更多
关键词 True Beam Medical Linear Accelerator commissioning Photon Beam Data Flattening Filter Flattening Filter Free
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