上海光源储存环机器保护系统升级

上海光源线站工程（二期）对机器保护系统提出的高要求是现有系统无法满足的,需对机器保护系统进行升级改造。本文使用FL-net技术实现了光源储存环所有联锁可编程逻辑控制器单元间的数据共享,解决了联锁系统跨单元通信的问题。机器保护系统的远程控制基于分布式EPICS设计,扩充部分通过统一接口形式和使用层次化设计方法,避免了对原系统的改动。新系统通过测试,在线运行可靠稳定,单元间联锁响应时间小于21 ms,满足加速器运行的需求,且改造后的系统更灵活、易扩充,可满足日后不同的联锁需求。     

同步辐射区光束线位置测量系统的控制和数据获取

介绍了上海同步辐射光源的X射线光束位置测量系统的控制和数据获取,具体描述了位置测量系统的控制和数据获取的总体设计、原理和软件系统,以及在上海同步辐射光源(SSRF)光束线线站的应用。     

冬季上海吴淞地区大气颗粒物PM10的元素主成分分析

从2002年12月到2003年2月,利用8通道采样器对上海吴淞地区进行3个月的大气气溶胶PM10(空气动力学直径小于10μm的颗粒)的采样。使用质子激发X射线荧光(PIXE)分析方法进行了多元素质量浓度测定,然后对获取数据进行主成分分析,讨论了吴淞地区8个风向采集的PM10中含有的主要化学元素成分和可能的来源。     

Development of a reduced order model for severe accident analysis codes by singular value decomposition aiming probabilistic safety margin analysis

ABSTRACT

Severe accident codes (e.g. MAAP, RELAP, and MELCORE) model various physical phenomena during severe accidents. Many analyses using these codes for safety margin evaluation are impractical due to large computational costs. Surrogate models have an advantage of quickly reproducing multiple results with a low computational cost. In this study, we apply the singular value decomposition to the time-series results of a severe accident code to develop a reduced order modeling (ROM). Using the ROM, the probabilistic safety margin analysis for the station blackout with a total loss of feedwater capabilities at a boiling water reactor is carried out. The dominant parameters to the accident progression are assumed to be the down-time and the recovery-time of the reactor core isolation cooling system, and decay heat. To reduce the number of RELAP5/SCDAPSIM analyses while maintaining the prediction accuracy of ROM, we develop a data sampling method based on adaptive sampling, which selects the new sampling data based on the dissimilarity with the existing training data for ROM. Our ROM can rapidly reproduce the time-series results and can estimate core conditions. By reproducing multiple results by ROM, a time-dependent core damage probability distribution is calculated instead of the direct use of RELAP5/SCDAPSIM.