基于GTL技术的高速背板总线设计

介绍了一个高速背板总线的设计尝试。采用新型的GTL总线收发器、时钟相位调节和组合式匹配等技术措施,解决了总线设计的驱动、时序和信号完整性问题,实现了100Mbd/s的同步数据传输。     

外热式等离子体实验装置数据获取和处理系统

介绍了外热式等离子体实验装置数据获取和处理系统的设计与实现。该数据获取和处理系统支持20通道差分信号采样,每通道最高采样率1Msps,基于USB2.0的数据接口的实时传输能力为10M Byte/sec,能够满足外热式等离子体实验装置等离子体流场采样测量的技术要求。     

手持式单板500MHz采样率数字化多道设计

针对Cs2LiYC16:CE(CLYC)闪烁晶体、掺硼塑料闪烁体等中子/γ探测器的电流脉冲波形的甄别,需要高速数字化多道脉冲幅度分析器。采用直接耦合方式设计高速模拟前端电路,将高速模数转换器(Analog-to-Digital Converter,ADC)配合现场可编程逻辑门阵列(Field-Programmable Gate Array,FPGA)芯片实现数字化设计,在FPGA内部实现了高速数字滤波、脉冲幅度提取、基线扣除、谱线存储与传输等功能。通过嵌入式的Power PC内核,实现替代外部控制器的复杂时序功能,并挂接通用串行总线(Universal Serial Bus,USB)外设芯片实现与外部计算机的高速双向数据传输。本文还设计了低噪声、大电流的开关电源,最终实现了可脱机独立运行的手持式单板高速数字多道。通过实测数字多道的模拟前端电路大信号带宽达110 MHz,小信号带宽达200 MHz,实时采样率为500 MHz,脉冲计数通过率大于107 s-1,线性度达0.999 8,连接NaI(Tl)、掺硼塑料闪烁体、LaBr_3(Ce)等闪烁体探测器实测谱线合理,满足实际使用要求。     

LabVIEW-based auto-timing counts virtual instrument system with ORTEC 974 Counter/Timer

In order to achieve the auto-timing counts measurement of nuclear radiation using ORTEC 974 Counter/Timer,an auto-timing counts virtual instrument system based on the LabVIEW virtual instrument development platform and GPIB instrument control and transmission bus protocol is designed in this paper.By introducing software timing technique,the minimum time base of factory setting improves from 0.1 s to 0.03 s.The timing counts performance and longtime stability are also discussed in detail.The automatic data recording and saving facilitates data analysis and processing.Its real-time display and statistic function is very convenient for monitoring the nuclear radiation.     

光纤在合肥同步辐射装置新时序系统定时信号传输中的应用

本文讨论一种利用高速光纤传输定时精度，低重复率触发信号的方法，此方法在两相邻定地脉冲的时间间隔加入周期脉冲，在接收端剔除叠加的周期脉冲，检出定时脉冲，解决了由于光接收器低端截止频率高于定时脉冲频率的矛盾。     

同步加速器束流能量自动切换控制系统

带电粒子放射治疗中3D主动治疗方式需要不同的束流能量照射不同的病灶切面,这就需要同步加速器控制系统能实现多级束流能量的自动切换控制并提供接口对接治疗计划进行自动变能控制。本文开发了同步加速器束流能量切换控制系统,同步加速器的前端服务器中存储着执行1个同步加速器加速周期所需的全部控制数据集,其中控制数据通过索引标号对其进行区分,同步事例信息是同步加速器多级束流能量切换的触发信号。当前端控制器被同步时间系统的同步事例触发激活后,从DSP波形发生器的SDRAM空间中读出磁铁电源、高频等控制数据进行数据切换。同步事例信号包含同步触发信息、束流能量控制数据的索引信息和控制数据的更新操作信息。多级束流能量自动切换控制系统能实现255级束流能量间自动切换控制（碳束能量在50～500 MeV间切换,步长可控制在1.77 MeV）,完全能满足实际中碳束能量在50～500 MeV间以10 MeV为步长的自动切换控制。     

A RPC test station based on ROOT and VME

Due to its advantages in large-area application situations, the RD of the resistive plate chamber(RPC)has always been carried out. A performance test station for RPC RD has been designed and developed based on the VME bus and ROOT in Linux. This system can be customized expediently according to the requirements of different tests, which facilitates detector RD because of its automatic HV scan, especially for long-term test. With this system, we have implemented the RPC performance test,including the efficiency curve, counting rate, dark current and charge and timing resolution.     

用于In-BeamTOF-PET的时间校正系统

设计和构建了用于In-BeamTOF-PET时间校正的定时系统。该系统是由1对BaF₂( 40mm× 45mm)晶体耦合到光电倍增管XP2020Q和标准核电子学插件构成。经测试,系统对511keV γ射线测量的最佳符合时间分辨达576ps。对光电倍增管、信号读取方式、定时放大器以及甄别器等对该定时系统时间分辨的影响进行了测试分析。结果表明：从光电倍增管打拿级引出信号的读取模式的系统分辨率最佳;光电倍增管类型,尤其是它的上升时间和电子渡越时间对定时系统性能影响较大。光电倍增管的上升时间和电子渡越时间越短,其定时性能越好。系统的定时性能也与电子学插件的组合有关。     

基于DRS4波形数字化的高速数据采集系统设计

针对一些粒子物理实验中高采样率、多参数测量以及长距离传输等要求,设计了一套基于DRS4波形数字化的高速数据采集系统。该系统由波形数字化前端板、高速数据传输板和上位机软件组成。测试结果表明,该数据采集系统具有较高的数据传输速率和较低的误码率,采集到的数据能很好地重建和还原输入信号波形。该数据采集系统具有一定的通用性,适用于对采样率和传输距离有较高要求的粒子物理实验。     

锆合金氧化膜的内应力计算

锆合金氧化膜中的内应力是锆合金腐蚀动力学中的重要影响因素,目前没有统一的方法得到氧化膜中内应力的大小,且数值差异较大。在传统的实验和理论方法的基础上,建立ZrO₂/Zr合金双层氧化弯曲几何模型,计算不同腐蚀状态下氧化膜中的内应力大小,得到内应力变化规律并分析其影响因素,为锆合金氧化膜内应力研究提供了一种较为可靠的方法。      

用于普通能谱实验室的基于VME总线的数据获取系统研制

介绍了一套基于VME总线的实验室数据获取系统的设计及应用。此系统主要针对普通核物理或探测器实验室的实验探测器系统,获取系统硬件用通用ADC插件作为模数转换,用基于VME总线的单板机算计进行数据传输。获取程序基于ROOT数据处理平台,可实现在线监控数据,并使用直方图等数据格式将数据存储。通过这套系统获得的碲锌镉探测器对241Am的59 keVγ射线能谱,数据获取速率达4 MB/s。这套数据获取系统可很好地应用在探测器测试及相关实验领域。     

Kicker磁铁电源控制系统设计

兰州重离子加速器冷却储存环包含多个注入和引出环节,其中较为关键的是CSRm的引出和CSRe的注入系统,其时间控制精度直接影响束流的注入引出效率。本文采用先进的ARM+FPGA技术实现对踢轨电源系统的精确控制,其时间控制精度达ns量级。ARM主要实现控制数据的下载与上传,踢轨系统的控制时序主要通过FPGA编程完成。远程时序控制信号均通过光纤传输,同时对踢轨电源的电压给定采用数字电位器技术实现,给定精度达0.1%。     

New CAMAC based data acquisition and beam control system for Lund nuclear microprobe

A new CAMAC based data acquisition system has been installed at the Lund Nuclear Microprobe facility. This paper reports on the development and present status of the data acquisition system. The system is a true multiparameter CAMAC based system with fast Fera bus readout and in crate memory buffer. The user interface is based on Sparrow Kmax software for a Power Macintosh platform. The system read out and tag the event data with position on-line, which make fast on-line monitoring of spectra or element maps possible.Simultaneously, all data can be saved event by event for off-line analysis. The beam scanning part is software controlled through a timed D/A converter, this allows fast scanning of the beam. With a CCD-camera and video card the area to be analysed could be defined directly from the image, and the sample position can be moved. Any kind of irregular scan patterns could be defined.     

The Designed Operation of the Machine Control System on HL-2A Tokamak

The Ethernet and field-bus communications are used in the machine control system （MCS） of HL-2A. The control net, with a programmable logic controller （PLC） as its logic control master, an engineering control management station as its net server, and a timing control PC connected to a number of terminals, flexibly and freely transfers information among the nodes on it with the Ethernet transmission techniques. The PLC masters the field bus, which carries small pieces of information between PLC and the field sites reliably and quickly. The control net is connected into the data net, where Internet access and sharing of more experimental data are enabled. The communication in the MCS guarantees the digitalization, automation and centralization. Also provided are a satisfactory degree of safety, reliability, stability, expandability and flexibility for maintenance.     

Erratum to “Thomson scattering upgrade on Tore Supra” [Fusion Eng. Des. 85 (2010) 335–339]

The Thomson scattering diagnostic supplies the electron temperature and density of Tore Supra plasmas from the spectrum analysis of scattered light of a very short laser pulse. A new spectrometer has been realized to improve the signal to noise ratio. In order to obtain an efficient noise reduction, a real time calculation is necessary. The current analogue integration of the signal is inadequate. A fast digitalization must be used with a sampling rate of 1 GSamples by second, a bandwidth of 150 MHz and a 12 bit dynamic range. In a first step, fast analogue data acquisition boards for 4 channels were added in 2009 to the VME acquisition system in place. A MATACQ (Matrix for acquisition) board was chosen for sampling analogue data up to 2 GSamples/s over 4 channels with a large bandwidth of 300 MHz and a 14 bit dynamic range. This solution offers a low cost acquisition system that is not available in any other commercial board with this dynamic range. The first results will be obtained on calibration period with a light emitted diode before the summer 2009. This article will present the new data acquisition system and the coming first results.     

~(60)Co船只辐射成像嵌入式数据获取系统设计

介绍了~(60)Co辐射成像检查系统中嵌入式数据获取系统的设计,重点介绍了基于模块化驱动和网络传输的嵌入式数据获取系统的组成,采用分时复用方式简化了系统各部分接口设计。嵌入式系统作为数据采集系统的控制中心,通过以太网接收上位机的控制命令,产生采集控制时序,从前置放大器读取数据并缓存、传输至上位机。经过对系统性能的测试,验证了该嵌入式数据获取系统具有连接接口简洁、便于扩展、性能稳定可靠的特点。     

Waveform digitization utilizing switched-capacitor arrays

Compared with traditional waveform digitization with flash-ADCs, waveform digitization with switched-capacitor arrays (SCAs) is able to achieve the sampling speed above 1 GS/s without degrading the analog to digital conversion precision significantly. In this paper, we present the implementation of a fast waveform digitization system with the use of SCAs, and evaluate its performance of waveform digitization and the waveform timing. At about 5 GS/s, the dynamic input range of the digitizer is about 66 dB, and its timing precision is about 20 ps (RMS).     

基于FPGA的8通道高速计数器的研制

介绍了一种基于FPGA的8通道高速定时计数器的NIM插件的设计原理与实现.电子学测试表明该插件能够响应最小脉宽为2ns的脉冲输入,最高计数率达到170MHz,定时精度为100ns.插件可以在联机和脱机两种模式下工作:联机工作模式下,PC机通过USB接口控制插件工作,实时地在主机上采集和显示各通道计数状态,并支持多个相同设备的热插拔;脱机模式下,可通过本地面板控制插件工作及显示各通道计数值.     

单晶硅受照热中子注量率的双箔活化法测量研究

由于活化箔材料和单晶硅目标核素的活化截面随中子能量的变化曲线形状不同,导致等效2200 m/s热中子注量率的活化箔法确定值与单晶硅目标活化率的对应值存在一定的偏差。为研究活化截面的变化差异对测量的影响,对热中子活化截面均服从1/v规律,但共振积分和2200 m/s热中子活化截面的比值相差较大的Zr箔和CoAl箔进行了测量比较。结果表明,由于超热中子对前者的活化率贡献更大,导致Zr箔确定的值明显高于CoAl箔的值,活化截面的变化差异对测量结果有显著影响。为消除该影响,采用通过两种活化箔确定的值和Stoughton-Halperin约定关系式建立方程组的方法,确定了与单晶硅目标活化率对应的等效2 200 m/s热中子注量率。