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51.
The Swedish National Testing and Research Institute (SP) asked its clients in its 2001–2002 customer satisfaction survey how they valued an accredited test result on a scale of 1-6. As many as 81% of the recipients answered that it was important (a score of 5 or 6 on the scale ) to have an accredited test result. 12% found the question irrelevant, which could be interpreted as that they used some of SPs non-accredited services, or were just not interested in accredited test reports.  相似文献   
52.
宁波天童森林公园两栖爬行动物初步调查   总被引:1,自引:0,他引:1  
在1994~2000年间记录了天童森林公园活动的两栖动物15种,隶属2目6科,爬行动物30种,隶属3目8科.两栖动物东洋界种占80.0%,古北界种占20.0%;爬行动物东洋界种占76.7%,古北界东洋界广布种占23.3%,具有南北过渡特征,并对其区系成分进行了分析.  相似文献   
53.
A survey of approximately 100 000 entries in recent releases of the Cambridge Structural Database (CSD) has uncovered 156 crystal structures that were apparently described in inappropriate space groups. We have revised these space groups and prepared CIFs containing the new coordinates and brief comments describing the revisions.  相似文献   
54.
The vast majority of racemic solutions of chiral compounds apparently crystallize at room temperature in non‐Sohncke space groups as racemic crystals. However, kryptoracemic crystals composed of nearly enantiomeric pairs occasionally crystallize at room temperature, or appear as low‐temperature phases, in Sohncke space groups. As a complement to the previously published catalog of organic kryptoracemates [Fábián & Brock (2010). Acta Cryst. B 66 , 94–103], 1412 chiral organometallic crystal structures have now been extracted from the Cambridge Structural Database and analyzed. 26 are listed herein as credible kryptoracemates. The possible influence of temperature is discussed, together with some problems in characterizing and classifying these structures.  相似文献   
55.
船用惯性系统试验安装标校与变形测量   总被引:3,自引:2,他引:3  
船用惯性系统试验安装标校和变形测量是提高测量精度,保证试验质量的关键技术,因此在对设备的安装误差和船体变形造成的测量误差进行分析的基础上,重点阐述惯性系统试验零位对准和变形测量的相关理论和工程技术。  相似文献   
56.
分析了动态条件下,载体姿态参数的惯性测量问题。以实际工程应用为背景,推导了运动约束条件下,基于两个激光陀螺,两个加速度计的系统姿态测量模型。根据载体姿态动态变化的不同频谱特性,进行了基于频域分析的算法设计,通过实验验证了算法的可行性。  相似文献   
57.
介绍了兰州重离子医疗装置(HIMM)建造中准直安装方案里核心的测量控制网设计。同步环准直测量控制网是基于Leica AT401激光跟踪仪和综合测量软件SA建立的三维测量控制网,在控制网设计中采用9个基准柱和2个激光干涉测量得到的基准长度参考,以及Leica DNA03数字水准仪协同测量,使全局三维控制网设计精度达到0.04mm,最终确保同步环四极磁铁安装精度达到0.10mm的要求指标,为将来束流的稳定运行做好可靠的保证。  相似文献   
58.
本报告描述了1992年中央人民广播电台全国听众抽样调查的设计、主要结果和特色.  相似文献   
59.
The science of solid state nuclear track detectors (SSNTDs)—“Trackology”—developed by R.L. Fleischer, P.B. Price and R.M. Walker in the early 1960s of the last century is an interesting and potentially useful concept with something to offer to almost all branches of science and technology. In fact nuclear tracks find applications wherever solid state damage occurs. Apart from the direct applications of far reaching consequences in nuclear physics, other areas as diverse as bio-medical sciences, cosmic rays and space physics, environmental research, geological sciences, material science, microanalysis, mine safety, nuclear technology, uranium prospecting, etc. have been greatly influenced by SSNTDs.

In this presentation, we attempt to provide an overview of the growth of nuclear tracks research in India over the last four decades and the contributions of various groups from Universities, Institutes, Nuclear Track Society of India and the Department of Atomic Energy in nurturing nuclear track research in the country. Finally, a summary of the significant contributions made by Indian scientists is also presented in this paper along with the overall impact it has made at the national and international level in many areas of basic and applied sciences such as cosmic rays and space physics, fusion–fission and particle evaporation, heavy ion ranges and energy-loss measurements, country-wide indoor radon–thoron survey, geochronology, environmental sciences, track-etch membranes and ion tracks technology, material science, physics and chemistry of fission, etc.  相似文献   

60.
During 1999-2001 the building research establishment (BRE) undertook a measurement based survey of environmental noise levels and a social survey of population attitudes to environmental noise in the UK. The surveys involved a total of 1160 24-h noise measurements at a sample of dwellings in the UK, and over 5500 in-depth interviews with a sample of the UK adult population. Both samples were of a clustered random design, and were representative of the UK population. The results of the surveys have been compared with those from similar surveys undertaken by BRE in 1990/1991 and are currently being used to help formulate a more strategic approach to the control of environmental noise both nationally and in London.  相似文献   
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