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101.
运用对偶标度统计方法计算儿童发展调查问题中原始数据的变量权和样本得分,从而确定评价因素集.采用多层前馈模糊神经网络——FM LP实现对儿童个体综合素质的定量评价. 相似文献
102.
在核电站安全研究中,概率安全评价方法已经得到了广泛的应用.但是对于采用非能动设计的核电站系统,其可靠性分析的研究还处于初级阶段.非能动系统的失效不但要考虑常规可靠性分析中考虑的设备失效,还要考虑物理过程的失效.物理过程失效概率的计算方法和能动系统可靠性分析方法完全不同.本文给出物理过程失效的数学描述,介绍了一次二阶矩法、响应面方法,并且应用响应面方法计算了清华大学核能技术设计研究院10MW高温气冷实验堆(HTR-10)余热排出系统失效概率的近似值.
关键词:
概率安全评价
非能动系统
可靠性
响应面 相似文献
103.
自然条件下,铂族元素(PGEs)一直被认为是表生条件下的痕量元素。但是,随着铂族元素在机动车排放催化剂及其他方面的广泛使用,最终导致Pt,Pd,Rh会排放到环境中。目前,铂族元素在环境中存在一定程度的积累现象,机动车尾气催化转换器被认为是其污染的主要来源。为研究北京市城区内道路尘土铂族元素的污染状况,于2010年11月采集了北京市内大型居民社区内的道路尘土样品。样品先经王水热消解以及阳离子交换树脂(Dowex AG50W-X8)分离纯化后,采用电感耦合等离子体质谱仪(ICP-MS)分析了道路尘土样品中三种铂族元素(铂(Pt)、钯(Pd)和铑(Rh))的浓度。结果表明:北京城区内居民社区道路尘土中Pd,Pt和Rh的含量范围分别为:14.20~161.80,9.39~70.80和3.18~17.05 ng·g-1,其平均浓度分别为50.76,23.82和7.54 ng·g-1,高于北京市土壤背景值, 说明北京城市居民社区内道路尘土中PGEs已经有了一定程度的富集。其中,Pd,Pt和Rh分别高于北京土壤背景值约49.8,32.6和5.1倍。为了定量评价道路尘土中PGEs的污染状况,采用地积累指数法对北京市道路尘土进行了评价。地积累指数法评价结果发现:大型居民社区内道路尘土中PGEs污染程度由强至弱的顺序依次为:Pd>Pt>Rh,总体而言,北京城区内大型居民社区内道路尘土存在较为明显的PGEs污染。 相似文献
104.
表面粗糙度的测量与评定一直是机械行业的重要课题。提出了一种基于机器视觉检测工件表面粗糙度的方法。首先利用显微镜获取端铣、刨、车不同等级下工件表面的序列图像,采用方差聚焦测度算子对序列图像中的每一个点进行高度计算;然后再利用高斯插值法计算出微观物体表面的准确高度,重构其表面微观形貌;最后计算出各个工件表面的三维粗糙度。通过对实验数据的分析和讨论,可以确定出表面均方根偏差Sq、表面偏斜度Ssk和表面峰密度Sds这三个参数,它们是常用地对工件表面粗糙度进行评价的可靠参数,可为以后三维粗糙度体系的科学建立提供依据。 相似文献
105.
106.
《应用有机金属化学》2017,31(12)
The tetradentate Schiff base ligand (SB), N,N′‐bis‐(2‐mercaptophenylimine)‐2,5‐thiophenedicarboxaldehyde was prepared via condensation of 2,5‐thiophene‐dicarboxaldehyde with 2‐aminothiophenol in a 1:2 molar ratio by conventional method. Additionally, its Co(II), Ni(II), Cu(II) and Zn(II) complexes have been synthesized and fully characterized by elemental analysis, FT‐IR, 1H NMR, 13C NMR, UV–Vis, ESR, ESI‐mass, conductivity and magnetic susceptibility measurements. Spectral studies suggested that, the Schiff base coordinate metal ions through the azomethine N‐ and deprotonated thiol S‐ atoms. Based on UV–Vis absorption and magnetic susceptibility data, tetrahedral geometry was assigned for both Co(II) and Zn(II) complexes, whereas on the other hand, square planar geometry for both Ni(II) and Cu(II) complexes. The Schiff base and its metal complexes were screened for their in vitro antimicrobial activity by minimum inhibitory concentration (MIC) method. Free radical scavenging activity of the novel compounds was determined by elimination of 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) radicals. In addition, the interactions of the free ligand and its complexes with calf thymus DNA (CT‐DNA) were explored using absorption, emission and viscosity measurements techniques. 相似文献
107.
The specific standard described here constitutes the heart of the quality system set up by the Commissariat à l'Energie Atomique
– French Atomic Energy Commission – for its main "Fundamental Research" entity, the Directorate for the Sciences of Matter.
It is a coherent standard (set of shared rules and provisions laid out in a clear fashion) designed, in the first instance,
to provide those taking part in research, including the hierarchy, with the means to satisfy their requirements in the field
of quality. And, secondly, to create the conditions for recognition of this action by third parties, which all research entities
must nowadays convince of their trustworthiness (supervisory ministries, research partners, industrial companies, etc.). This
standard places particular emphasis on the preponderant roles of initiative and freedom in fundamental research, which are
a prerequisite for creativity, innovation and, last but not least, the motivation of personnel. 相似文献
108.
W. Kleiböhmer 《Accreditation and quality assurance》1999,4(12):517-520
Maintaining a high quality of research and development (R&D) is fundamental for the competitiveness of European industry.
The development of new technologies and the improvement of existing technologies, products, production processes, measurement
instrumentation and methods as well as basic research is essential. The objective of the workshop on "Quality Management in
Analytical Chemical Research and Development" was to bring together experts from the academic world, industrial and institutional
laboratories and also accreditation bodies to discuss the actual state of the art in the field of quality management in R&D,
and to set up milestones for further activities. Furthermore, an important objective was to present the EURACHEM/CITAC Guide
2. The paper outlines the programme of the workshop and summarises the round-table discussions and expert recommendations.
Most of the contributions to the round-table discussions will be published as full papers in a forthcoming issue of Accreditation
and Quality Assurance. The workshop was organised by the Institut für Chemo- und Biosensorik (ICB), Münster, with the financial
support of the SMT-Programme of the European Commission (Contract No.: SMT4-CT98-6534). 相似文献
109.
Jean-Claude Petit 《Accreditation and quality assurance》1999,4(11):458-462
An appropriate Quality approach in fundamental research should have its roots in the very principles of the "scientific method".
Quality and fundamental research could thus reconcile at the condition, on the one hand, that Quality practioners understand
and take into account the reality of the "science in action" and, on the other hand, that scientists improve their awareness
of the new deal which is being made between science, technology and society as well as of the actual issues of Quality. A
modern Quality approach, well adapted to this specific activity, should help both scientists, decision-makers and the public
face the issues concerning the role of science in society in the future. In this context, I specify a number of practical
proposals concerning, in particular, the adaptation of the requirements of the quality approach to the type of research, the
distinction between the three major steps of a research programme (i.e. quality of the objective, the process and the results)
and the encouragement of experience feedback.
Received: 8 March 1998 / Accepted: 8 December 1998 相似文献
110.
Klaus Reber 《Accreditation and quality assurance》1999,4(4):156-157
The Swiss Federal Laboratories for Materials Testing and Research (EMPA) have established a quality assurance system based
on EN 45001 which meets the requirements for accreditation of all EMPA's testing activities. As testing is only a part of
EMPA's range of activities, and is performed in decentralised departments, the system does not satisfy the management needs.
The fundamental reorganisation of EMPA's St. Gallen site was used as an opportunity to implement an overall process-oriented
management system which also included quality and the needs for accreditation. Later, an environmental management system was
added and then certified for ISO 9001 and 14001. The system consists of a "Management Manual" for the St. Gallen site and
a customised "Quality Manual" for each department. One of the key elements is a comprehensive review and planning procedure
covering all business aspects. 相似文献