核仪器系统的仿真及其实现

针对核物理实验的特殊性,设计了一套基于LabVIEW平台的、在核物理实验中常用的核仪器仿真系统,包括核随机信号发生器、单道脉冲幅度分析器、定标器等插件仪器的仿真与集成.运用该系统进行了部分本科核物理实验的实验验证.结果表明,系统中核随机信号发生器所产生的仿真信号符合核脉冲信号的统计规律,仿真系统界面逼真,操作与真实的实验操作基本一致.该仿真系统的应用对于掌握常规核辐射探测方法及避免实验中可能的辐射损伤具有实际意义.     

The MPO API: A tool for recording scientific workflows

Data from large-scale experiments and extreme-scale computing is expensive to produce and may be used for high-consequence applications. The Metadata, Provenance and Ontology (MPO) project builds on previous work [M. Greenwald, Fusion Eng. Des. 87 (2012) 2205–2208] and is focused on providing documentation of workflows, data provenance and the ability to data-mine large sets of results. While there are important design and development aspects to the data structures and user interfaces, we concern ourselves in this paper with the application programming interface (API) – the set of functions that interface with the data server.Our approach for the data server is to follow the Representational State Transfer (RESTful) software architecture style for client–server communication. At its core, the API uses the POST and GET methods of the HTTP protocol to transfer workflow information in message bodies to targets specified in the URL to and from the database via a web server. Higher level API calls are built upon this core API. This design facilitates implementation on different platforms and in different languages and is robust to changes in the underlying technologies used. The command line client implementation can communicate with the data server from any machine with HTTP access.     

先进核反应堆专家评估系统架构的设计和实现

先进核反应堆专家评估系统是核电反应堆评估软件系统开发的初次尝试。本系统在VisualStudio.NET开发平台上，使用C＋＋编程语言，在Model-View-Control（MVC）体系架构的基础上实现了系统的具体功能。在国内先进反应堆的评估运用实践中表明，该系统的设计是可行有效的。     

核能谱模拟的正态组合实现方法

结合核能谱的随机特性,探讨了核能谱的正态组合模拟方法。该方法将核能谱分解为正态分布函数的组合,进而转化为参数化模型,并对正态组合函数进行随机抽样以模拟原始能谱。该方法可以灵活地调整正态函数的个数和各正态函数的标准偏差,以满足模拟中对谱线平滑度、准确度的不同要求,是一种效果较好的参数化模拟方法。     

Nuclear magnetic resonance: A new tool for the validation of multiphase multidimensional CFD codes

Turbulent transport models and data in bubbly flows are briefly reviewed since they play an important role in the modeling of boiling flows in forced convection. Shortcomings of earlier measurements of the eddy diffusivity by NMR (Lemonnier and Leblond, 2007b) are analyzed and a new procedure is presented which is now consistent with the procedure of Gatenby and Gore (1994) developed for single-phase turbulent flow characterization. The newly estimated eddy diffusivity agrees now with that previously obtained by Serizawa et al. (1975b) with a thermal method and that of the model of Sato and Sadatomi (1981). This procedure also provides the liquid velocity fluctuation RMS and the Lagrangian correlation time of velocity fluctuations. In addition, the same NMR technique provides also the area-averaged liquid velocity and void fraction. Bubbly flow data up to transition to slug flow are provided which also agree with existing drift-flux models (Ishii and Hibiki, 2006). It is finally discussed how the NMR method can be extended to local measurements and may provide a fully non-intrusive diagnostic in two-phase flows and which is not limited to bubbly flow.     

一种仿252Cf中子源随机脉冲信号参数检测系统的FPGA设计与实现

从252Cf自发裂变中子源之裂变中子在时间分布上相互独立的基本原理出发,针对随机核信号在时间上呈泊松分布,在幅度上服从高斯分布这一特征,开展了基于FPGA技术的仿252Cf中子源随机核信号产生及其脉冲参数的检测研究。研究结果表明,仿252Cf中子源随机核脉冲参数检测系统,在脉冲上升沿或下降沿到达后的第一个时钟周期,便能开始输出检测结果,满足了随机脉冲参数检测的实时性要求。通过观察LabVIEW GUI上显示的参数检测结果,与核脉冲的计数率、幅度统计特性、时间间隔统计特性基本相吻合,表明基于FPGA的仿252Cf源的核信号参数检测系统是切实可行的。     

Properties of Plutonium Dioxide as Nuclear Fuel

Generalized structural, thermodynamic, thermophysical, and strength characteristics as well as data on the dimensional stability, compatibility, and fragment gas release under irradiation of plutonium dioxide, used as a compact nuclear fuel for fuel elements in fast research reactors, are presented. Reliable operation of reactors with fuel elements based on plutonium dioxide confirmed that the properties of the fuel ceramic of fuel elements with austenitic stainless steel cladding have been determined with a high degree of reliability. 7 figures, 6 tables, 23 references.     

PSA as a tool for decision making

The question on “How safe is safe enough?” is being responded presently by deterministic criteria. Probabilistic criteria in support to more rational and less emotional decisions in regulatory and licensing issues, rationalization of resource allocation and research prioritization, among others, have a potential which is only marginally being explored.This paper discussed PSA limitations and proposes three areas for the use of PSA in decision making, namely:

1. (a) preventing accidents,

2. (b) mitigating accidents, and

3. (c) defining regulatory requirements.

Current activities of the International Atomic Energy Agency in these areas are mentioned.PSA studies depict clearly the uncertainties and this is viewed as a positive aspect, which is unique to the use of probabilistic methods.     

大亚湾核电站全范围模拟机硬件I／O实现

广东大亚湾核电站全范围模拟机(以下简称模拟机)是从法国汤普森公司引进的。它是用数字仿真技术对大亚湾核电站主控制室进行1:1高保真模拟的大型设备,用于培训核电站的操作运行人员、系统分析包括对操作规程的验证等。模拟机的 I/O 接口系统是计算机与各种开关、仪表交换信息的桥梁。本文力求从数据传输的角度,结合程序流程图论述 I/O 接口系统的工作原理。     

Nuclear Data and Nuclear Model Methods

Developing nuclear data needs towards to sustainable development on fission reactor design and many nuclear applications out the field of fission reactor technology that are growing economicsignificance and that have substantial data requirements are introduced. International standard codes used in nuclear data evaluations and calculations are introduced and compared each other. Generally     

Exploring reciprocity as a tool in low-energy electronic stopping

A computer code has been developed to explore reciprocity, i.e. the equivalence of electronic stopping cross sections for the ion-target pair A in B with that for B in A in the regime around and below the Bohr speed. With the aim of establishing reciprocity as a tool for identifying reliable experimental data and interpolating between them, we have studied stopping cross sections involving carbon, aluminium and gold either as projectile ions or as target materials. The case of carbon - where numerous data are available - is used to illustrate in detail various options to establish a body of credible data. Aluminium and gold serve to illustrate the case where these elements mostly are found as target materials in available data.