Comments on Abrahams and Alf's "Pratfalls in moderator research."

Reviews and comments on problems and pratfalls involved in moderator search strategies. Many arguments advanced by N. Abrahams and E. Alf(see PA, Vol. 49:Issue 1) are shown to be only partially relevant. Their arguments against quadrant analysis and against Ghiselli's "d" technique are criticized, and a distinction is made between grouping Ss on a psychometric and on a conceptual basis. 2 modifications of moderator search techniques are suggested: (a) a modified quadrant analysis, and (b) a 2-stage procedure for combining Ghiselli's "d" technique with a directional strategy. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

氢化锆慢化熔盐堆钍铀转换性能初步分析

中子能谱对钍基燃料在熔盐堆中的利用效率及温度反馈系数等安全问题有较大影响,所以对熔盐堆新型慢化剂的研究具有重要意义。本工作基于SCALE6计算程序,对不同几何栅元结构的氢化锆栅元组件在熔盐堆的物理性能进行了研究,分别计算了中子能谱、钍铀转换比、~(233)U浓度、总温度反馈系数以及燃耗等中子物理参量。结果表明,减小六边形栅元对边距或者增加熔盐占栅元体积比可以增加钍铀转换比和改善温度反应性系数;当加入的氢化锆慢化剂体积份额为0.1时就可以将熔盐堆~(233)U初始浓度降低到2.5×10~(-2)以内;氢化锆慢化熔盐堆在超热谱条件下,其~(233)U初装载量和超铀核素产量较小,同时堆芯较为紧凑。     

噪声法测量临界装置温度系数实验研究

为了用噪声法测量核电站反应堆的负慢化剂反应性温度系数(MTC),本文在铀溶液临界装置上研究噪声法实验测量反应性温度系数αT,并与周期法测量的αT进行比较。结果表明,两种方法测量的αT趋势基本一致。由于铀溶液临界装置中溶液的反应性温度效应与核电站反应堆的慢化剂温度效应的机理相似,因此本文利用噪声法测量铀溶液临界装置的αT对于核电站反应堆利用噪声法测量MTC有一定的参考价值。     

Measurements of neutronic characteristics of rectangular and cylindrical coupled hydrogen moderators

Extensive simulation calculations were performed in the design studies of the coupled hydrogen moderator for the pulsed spallation neutron source of the Japan Proton Accelerator Research Facility (J-PARC). It was indicated that a para-hydrogen moderator had an intensity-enhanced region at the fringe part, and that pulse shapes emitted from a cylindrical para-hydrogen moderator gave higher pulse-peak intensities with narrower pulse widths than those from a rectangular one without penalizing the time-integrated intensities. To validate the peculiar distribution and advantages in pulse shapes experimentally, some measurements were performed at the neutron source of the Hokkaido University electron linear accelerator facility. It was observed that the neutron intensity was enhanced at edges of the para-hydrogen moderators, whereas it decreased at the same part of the ortho-rich-hydrogen moderator, where the dimension of those moderators was 50 mm in thickness and 120 mm in width and height. The spatial distribution and pulse shapes were also measured for a cylindrical coupled para-hydrogen moderator that has the same dimensions as for the coupled moderator employed for J-PARC. The measured results from the cylindrical moderator were consistent with the results obtained in the design studies for the moderator for J-PARC.     

Examining the ICT access effect on socioeconomic development: the moderating role of ICT use and skills

This paper examines the role that Information and Communication Technologies (ICT) play in the socioeconomic development of countries. The proposed model analyzes the relationship between ICT access (available ICT infrastructure and individual’s access to ICT), ICT use (ICT intensity and usage, and ICT skills), and socioeconomic development. The methodology employed consists of a Structural Equation Model (SEM). To achieve this goal, country-level data across 163 countries for the year 2013 is used from developing to developed countries. Results obtained indicate the moderating role of ICT use and skills in the relationship between ICT access and the socioeconomic development. The ICT usage and ICT skills enhance the effect of ICT access on the socioeconomic development. The model is robust with respect to the development level.     

中国先进研究堆(CARR)冷中子源装置设计

对中国在建的核功率为60 MW的中国先进研究堆中冷中子源系统的设计作了总体描述.该冷中子源采用液氢作为慢化剂,主要由两个分系统氢循环系统和氦制冷系统构成.氢循环系统中的冷包设计为带氦助冷通道的液氢层为月牙形的冷包.氢在连接冷包与氢氦换热器的单管内进行两相热虹吸循环.冷包材料和慢化剂氢的核发热通过氦制冷系统产生的冷氦带走,氦制冷系统采用带液氮预冷的逆布雷顿制冷循环.     

Visual performance management as a fitness factor for Lean

Visual performance management (VPM) is a bundle of practices where visual techniques are used to offer timely information to shop-floor employees about the performance of processes. We investigate whether VPM contributes to the beneficial effects of Lean, and if so, what the relationship is between VPM and other Lean practices. Thus, the study builds on and adds to the stream of research that tries to establish how the various practices associated with Lean depend on and reinforce each other. Based on the outcomes of a survey, we establish that VPM is positively related with operations improvement. This effect is not direct, but mediated by Lean practices such as just-in-time and quality management. We conclude, therefore, that VPM should be seen as an infrastructural practice that reinforces an organisation’s general fitness, and acting as an enabler for more dedicated Lean practices. In addition, we find that VPM positively moderates the effects of Lean practices, which supports the same conclusion.     

ZrH2+2B体系自蔓延燃烧模型

研究建立了ZrH2 2B体系燃烧反应的近似数学模型。该燃烧模型反映了ZrH2 2B体系自蔓延燃烧过程的主要特点 ,模型的计算结果能很好解释实验现象 ,并能为实际生产工艺提供分析     

长中子计数管探测效率的模拟

为获得较高的探测效率且在较大范围内对中子有比较平坦的能量响应曲线,用蒙特卡罗程序研究了聚乙烯慢化体结构对BF3长正比计数管的中子探测效率的影响。模拟结果表明,增大慢化体半径可增加计数管探测效率,调节计数管前端慢化体厚度可改善能量响应曲线高能部分的平坦度。另外,利用建立的模型计算了1套现有的长硼计数器对D-D(2.4MeV)及D-T(14.1MeV)中子的相对探测效率。模拟结果为探测系统对D-D中子的探测效率为对D-T中子的75％,而加速器标定的实验结果为61％。两者可认为是近似一致的,这从实验上验证了模拟模型的可靠性。