数字化核测量仪表的研制

介绍了数字化核测量仪表的设计与算法分析，给出了数字化核测量仪表的工作原理，以及单片机为核心的硬件，软件的实现方法，实现准则，实现意义和反应堆测量的一些算法分析。     

基于LabVIEW的核信号数字滤波器的研制

本文介绍了基于LabVIEW的核信号数字滤波器的设计与测试。该数字滤波器实现了3种核信号的数字滤波成形方法--基于小波分析技术的高斯滤波成形、匹配滤波成形和梯形滤波成形。为验证该滤波器的性能,利用计算机产生的数字化核脉冲信号作为信号源,对各种滤波成形算法的效果进行了测试。测试结果表明,该数字滤波器的性能良好,参数调节方便,适用于对核信号进行数字滤波成形。     

数字化核测仪表的设计与算法分析

介绍了数字化核测仪表的设计与算法分析，给出了数字化核测仪表的工作原理，以及以单片机为核心的硬件、软件的实现方法、实现准则，以及对反应堆测量的一些算法分析。     

基于无线局域网的多道脉冲幅度分析器

介绍了一种基于无线局域网络技术的数字化多道脉冲幅度分析器的设计,根据无线局域网络的特性改进了能谱数据存储结构与传输算法,减小了多道系统的死时间。使用无线局域网技术将多道系统与上位机无线互联,可以实现远程核脉冲信号采集与分析,减少工作人员现场操作仪器所受的辐射剂量。     

DMCA中基于补偿最小二乘法的基线估计算法

介绍了一种用于数字化多道脉冲幅度分析(DMCA)中的基线估计算法。该算法针对核脉冲信号尾部衰减很慢的特点,首先对核脉冲信号死时间内的信号作直线替代预处理,以减小核脉冲信号尾部对基线估计的影响,然后用补偿最小二乘法对预处理后的信号进行拟合,从而估计出基线。仿真结果表明,本文算法估计出的基线平滑稳定,能够很好的逼近真实基线。通过与常规算法估计结果的均方误差作对比,得出本文算法具有更高的基线估计精度。     

基于FPGA的核信号高速采集系统的设计

对核信号高速采集系统的研究可实现数字核信号处理方法的改进与算法的验证,以及对数字化核能谱测量系统性能指标的提升具有重要意义。研发一套核信号高速采集系统,通过高速ADC将信号调理电路输出核脉冲信号进行采样,同时在FPGA系统中实现FIFO、USB接口传输功能,将采样后的数据经过FIFO缓存,再通过USB接口传送给后续计算机系统进行保存、显示与进一步处理。在搭建的核信号采集系统上进行测试,通过对5、10、20与33.3 MHz采样率下得到的核信号进行分析与讨论,表明该系统可有效地实现核信号的高速采集。     

任意分布的高速仿核信号发生器

针对核信号在时间、幅度上的随机性,探讨模拟核信号的发生装置。采用基于混合同余法、舍选控制法的蒙特卡洛方法在MATLAB中产生任意分布随机波形数据。高速FPGA通过串口接收上位机发出的控制命令和波形数据并存储在双口RAM,利用控制命令快速实现DDS技术和外部DAC,从而实现具有统计特性的核信号。实验结果表明所设计的仿核信号发生器能够有效模拟真实核信号的发生,对数字化核测量系统研究工作有重要意义。     

数字化能谱获取中梯形成形研究

在数字化能谱采集系统中,往往需要添加适当的脉冲成形算法对数字化核信号进行处理,以提升系统能量分辨率等指标。梯形成形算法因具有实现简单、成形脉冲窄等诸多优势而得到广泛的应用。从探测器输出的脉冲信号进行数学模型建立及简化出发,对信号模型的梯形成形算法进行分析讨论,并利用Simulink在现场可编程逻辑门阵列(Field-Programmable Gate Array,FPGA)上实现并改进梯形成形算法,通过实验测试了成形算法的可行性及其在能谱测量过程中对能量分辨率的提升。     

堆外核测量系统的数字化设计

为实现堆外核测量系统的数字化,在原有模拟电路基础上,对堆外核测量系统的数据处理和控制部分进行数字化设计。本文提出了使用工业级集成化PC/104模块电路的硬件平台和使用BOR.LANDC++开发的核安全级软件程序的方案实现核测量系统的数字化,描述了堆外核测系统数字化的软硬件设计,介绍了样机在堆上试验的数据等。实验测试表明:该系统具有高稳定性、安全性、快速响应性、确定性和可扩展性,满足堆外核测量系统的设计要求。     

基于冲激响应不变法的核信号数字滤波成形算法研究

核能谱测量仪器中,常将探测器的输出信号成形为需要的波形,以滤除噪声并将信号成形为方便后续分析的波形。提出了一种数字滤波成形算法。根据模拟CR-RC成形电路,推导出模拟成形系统的单位冲激响应;再用冲激响应不变法实现从模拟域到数字域的转换,得到数字高斯成形系统的冲激响应;将数字核脉冲信号与该单位冲激响应进行卷积和运算实现数字成形。仿真信号及实测采样信号的结果验证了算法是有效的,有效的滤除噪声的同时核脉冲信号被成形为准高斯信号。     

数字化多道脉冲幅度分析技术研究

多道脉冲幅度分析技术正在朝数字化方向发展,基于数字信号处理技术的数字化多道具有脉冲处理能力强、速度快、稳定性高和灵活性强等特点。文章分析了数字核脉冲处理关键技术,利用MATLAB完成了梯形成形、数字基线估计、数字极零零极补偿、极零点识别等核心算法的模拟。给出了数字化多道初步总体设计方案,探讨了工程没计中的关键技术问题,为研制国产数字化核谱仪打下了基础。     

Test bed for real-time image acquisition and processing systems based on FlexRIO,CameraLink, and EPICS

Image diagnostics are becoming standard ones in nuclear fusion. At present, images are typically analyzed off-line. However, real-time processing is occasionally required (for instance, hot-spot detection or pattern recognition tasks), which will be the objective for the next generation of fusion devices. In this paper, a test bed for image generation, acquisition, and real-time processing is presented. The proposed solution is built using a Camera Link simulator, a Camera Link frame-grabber, a PXIe chassis, and offers software interface with EPICS. The Camera Link simulator (PCIe card PCIe8 DVa C-Link from Engineering Design Team) generates simulated image data (for example, from video-movies stored in fusion databases) using a Camera Link interface to mimic the frame sequences produced with diagnostic cameras. The Camera Link frame-grabber (FlexRIO Solution from National Instruments) includes a field programmable gate array (FPGA) for image acquisition using a Camera Link interface; the FPGA allows for the codification of ad-hoc image processing algorithms using LabVIEW/FPGA software. The frame grabber is integrated in a PXIe chassis with system architecture similar to that of the ITER Fast Controllers, and the frame grabber provides a software interface with EPICS to program all of its functionalities, capture the images, and perform the required image processing. The use of these four elements allows for the implementation of a test bed system that permits the development and validation of real-time image processing techniques in an architecture that is fully compatible with that of the ITER Fast Controllers. This paper provides a specific example of a pattern search in a movie, its real-time implementation, and a performance analysis of the entire platform.     

Construction and Implementation of the Online Data Analysis System on EAST

In order to obtain diagnostic data with physical meaning,the acquired raw data must be processed through a series of physical formulas or processing algorithms.Some diagnostic data are acquired and processed by the diagnostic systems themselves.The data processing programs are specific and usually run manually,and the processed results of the analytical data are stored in their local disk,which is unshared and unsafe.Thus,it is necessary to integrate all the specific process programs and build an automatic and unified data analysis system with shareable data storage.This paper introduces the design and implementation of the online analysis system.Based on the MDSplus event mechanism,this system deploys synchronous operations for different processing programs.According to the computational complexity and real-time requirements,combined with the programmability of parallel algorithms and hardware costs,the OpenMP parallel processing technology is applied to the EAST analysis system,and significantly enhances the processing efficiency.     

次声波图数字化系统

介绍一套次声波形图数字化系统。该系统以图像处理技术为基础提供次声波形图扫描,倾斜矫正,图像剪切,去除水平线和垂直线,波形跟踪等功能。其关键技术包括小波分析、图像细化和像素跟踪。该系统使用户可以用计算机处理分析记录在图纸上的次声波形,使次声研究更加快捷方便,为大气核爆炸监测,爆炸源定位和当量计算,地震预测预报等研究提供一种先进的次声数据分析和管理方法。     

核电子学与核探测技术领域中的计算机应用问题

文中对近十年来核电子学与核探测技术领域内计算机应用的状况作了概括;简要的讨论了能谱数据获取、计算机断层成象、以及大型数据获取等系统方面的技术进展。对值得注意引用的计算机学科内发展起来的一些新技术与新技术产品作了简单的评价。     

Digital Image Processing

In this paper we give a tutorial overview of the field of digital image processing. Following a brief discussion of some basic concepts in this area, image processing algorithms are presented with emphasis on fundamental techniques which are broadly applicable to a number of applications. In addition to several real-world examples of such techniques, we also discuss the applicability of digital image processing to one particular field, that of medical radiography.     

虚拟技术在核谱仿真与处理系统中的应用

介绍了基于图形化编程环境的LabVIEW平台在核谱仿真和处理系统中的应用,该系统具有核谱分布的模拟、平滑处理、寻峰、感兴趣区的计算等一系列功能。     

Adaptive digital spectroscopy in programmable logic

High data rate in nuclear spectroscopy can be achieved by using digital shaping techniques. Currently, the use of held-programmable gate arrays as digital processors is hugely increasing, especially in real time applications. In this paper, we deal with the problem of the minimization of the computation burden, in order to allow the use of the least possible hardware, which in turn allows the minimization of power dissipation, size etc., of the processing machine. In order to get at-most advantages of spatial computing in programmable devices, data-path structures of temporal computing process techniques have been revised. Among the improvements consequent to the optimization of architectures, we address three topics: reduction of processing speed, resource saving, and adaptive dynamic management of digital filters length for increasing resolution     

Analytical and experimental studies of the modeling of a class of nonlinear systems

This paper deals with the identification of complex structural and mechanical systems often encountered in the nuclear industry. Nonparametric identification techniques are used to analyse the response of a class of nonlinear components. Efficient computational algorithms and experimental techniques based on nonparametric system identification methods such as the Wiener-kernel approach and least-squares regression techniques involving the system state-variables are developed and applied to an example system. The variation of system signature with its change in characteristics is studied and the effects of various parameters of the excitation, system, and the computation algorithm on the signature analysis are investigated. The use of the methods for modelling of realistic systems is evaluated and found to be promising. They appear to hold out considerable hope in the damage assessment of critical facilities such as nuclear reactors.     

数字化核能谱获取中信号处理方法的研究

介绍了将核辐射能量信号离散化后进行数字极零识别及补偿、基线扣除、低通滤波、脉冲成形和幅度分析等一系列数字化信号的处理方法，将长尾指数衰减信号成形为梯形波或三角波信号。用所述方法对实测波形进行离线处理后的结果表明，所获能谱的能量分辨率好于模拟式多道系统的测量结果。