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41.
The International Organisation for Standardisation (ISO) has published many guides, or technical standards, of great value to analytical geochemists. Two of particular importance are Guide 33 (Uses of Certified Reference Materials) and Guide 35 (Certification of Reference Materials). Both were first developed in the 1980s and undergo regular review and updating by the Reference Materials Committee (REMCO) that operates within ISO. Recent revisions have focused on adding statistical rigour to both guides. Although this offers significant advantages for use by professional metrologists, there are consequent issues of comprehension by the analytical chemists who in fact have the greatest need of them. A major focus of Guide 35 is the development of reference material uncertainties that are in full compliance with the Guide on Measurement Uncertainty (GUM), jointly issued by ISO, IUPAC and others. Guide 35 details handling of uncertainty due to (1) degradation on the shelf and in transport, (2) sample heterogeneity and (3) inter‐method and inter‐laboratory bias, as well as within‐laboratory repeatability. The International Association of Geoanalysts has developed a protocol for reference material certification that applies Guide 35 to the specific needs of the geoanalytical community. The approach being taken by the IAG in developing GUM‐compliant uncertainties for its certified values is presented. Recommendations made in Guide 33 for how a laboratory should compare its own results with certified values in assessing laboratory accuracy are outlined. Additionally, the subject of misusing reference materials is discussed. The apparent misuse occurs because so few CRMs exist that meet critical measurement needs of geoanalytical laboratories and that also meet the rigorous metrological demands of the latest editions of the ISO Guides. All of the focus of the IAG certification programme has been to undertake certifications that would fill gaps in CRM availability and thus serve to limit this misuse.  相似文献   
42.
Development of a system of indicators for sustainable port management   总被引:2,自引:0,他引:2  
The 1998 project ECOPORT, “Towards A Sustainable Transport Network”, developed by the Valencia Port Authority (VPA), established the bases for implementing an Environmental Management System (EMS) in industrial harbours. The use of data and information shall always be required to develop an efficient EMS. The objective of the present research (INDAPORT) study is to propose a system of sustainable environmental management indicators to be used by any port authorities. All activities performed within a port area are analysed for any potential environmental impacts and risks.

An environmental analysis of port activities has been carried out with the objective of designing the indicators system. Twenty-one corresponding activities have been identified for large industrial ports. Subsequently, the same methodology developed to date will be later applied to other Spanish and European ports. The study has been developed by using an original system and a methodology, which simultaneously use stage diagrams and systemic models (material and energy flow charts). Multi-criteria analysis techniques were used to evaluate potential impacts (identification of factors and evaluation of impacts).  相似文献   

43.
Intraseasonal Oscillation in the Tropical Indian Ocean   总被引:1,自引:1,他引:1  
1. Introduction The intraseasonal oscillation (ISO or Madden- Julian Oscillation, MJO) in the tropical atmosphere has been studied extensively, including its existence, structure, evolution and propagation (Madden and Ju- lian, 1971; Murakami, et al., 198…  相似文献   
44.
S-100的体系结构和若干重要概念   总被引:1,自引:0,他引:1  
S-100海道测量数据空间标准是国际海道测量组织(IHO)为适应海道测量信息标准化新要求而开发的海道测量空间数据标准。着重介绍了S-100作为S-57替代标准的新特质,对其具体内容与ISO 19100系列标准做了对照,介绍了两者的关系。S-100通过采用崭新的标准化理念,实现完全与国际主流地理空间标准接轨。  相似文献   
45.
孟加拉湾西南季风与南海热带季风季节内振荡特征的比较   总被引:4,自引:2,他引:2  
李汀  琚建华 《气象学报》2013,71(3):492-504
采用美国国家环境预报中心的向外长波辐射和风场资料及日本气象厅的降水资料,用30-60d滤波后的夏季风指数在孟加拉湾和南海的区域平均值分别代表孟加拉湾西南季风和南海热带季风季节内振荡,对两支季风的季节内振荡特征进行比较分析,发现孟加拉湾西南季风的季节内振荡和南海热带季风的季节内振荡在夏季风期间(5-10月)都有约3次半的波动.夏季风期间,在阿拉伯海-西太平洋纬带上,夏季风的季节内振荡有4次从阿拉伯海的东传和3次从西太平洋的西传,其中7月后东传可直达西太平洋.孟加拉湾和南海在夏季风期间都有4次季节内振荡的经向传播,但孟加拉湾在约15°N以南为季节内振荡从热带东印度洋的北传,在约15°N以北则为副热带季风季节内振荡的南传;而在南海则是4次季节内振荡从热带的北传.在以孟加拉湾西南季风季节内振荡和南海热带季风季节内振荡分别划分的6个位相中,都存在1-3位相和4-6位相中低频对流、环流形势相反的特征,这是由热带东印度洋季节内振荡的东传和北传所致.热带印度洋季节内振荡沿西南-东北向经过约14d传到孟加拉湾,激发了孟加拉湾西南季风季节内振荡的东传,经过约6d到达南海,激发了南海热带季风季节内振荡的北传,经过约25d到达华南,形成热带印度洋季节内振荡向华南的经纬向接力传播(45d).孟加拉湾西南季风季节内振荡所影响的降水主要是在20°N以南的热带雨带随低频对流的东移而东移;而南海热带季风季节内振荡所影响的降水除了这种热带雨带随低频对流的东移外,还有在20°N以北的东亚副热带地区存在雨带随南海低频对流的北移而北移.  相似文献   
46.
国际标准ISO90 0 2是由ISO(国际标准化组织 )质量标准和质量保证技术委员会制定的。建立质量体系的过程是质量体系的策划与准备、质量体系文件的编制、质量体系程序文件的运行、以及改进和完善质量体系并保证其有效运行的全过程  相似文献   
47.
ISO/TC211首批研制的20项地理信息国际标准,是一组结构化的、定义、描述和管理地理信息的标准。本文分5方面内容,分别剖析ISO/TC211首批研制的各项标准的适用范围、主要内容、结构或特点等,以帮助读者更好地和容易地理解标准的内涵,从而能更好地吸取其精华,为我所用。  相似文献   
48.
利用ECMWF逐日再分析资料(1961—2000年),中国气象局国家气候中心提供的1961—2000年中国160个站降水资料,探讨了夏季逐月南海和南亚ISO的强弱对南海和南亚夏季风及中国东部降水的影响。研究表明,夏季各月南海和南亚ISO异常对夏季风活动及中国东部降水的影响存在显著的差异,有分月进行讨论的必要。夏季各个月南海大气ISO的异常对南海和南亚夏季风活动的影响在6、7月有些相似,都表现为ISO强(弱)与南海地区和南亚地区气旋性(反气旋性)环流相对应,而8月截然相反,ISO强(弱)与仍南海地区气旋性(反气旋性)环流对应,而南亚地区表现为反气旋性(气旋性)环流。南亚大气ISO异常对夏季风活动的影响与南海地区有较大差异,6月和8月南亚大气ISO强(弱)与南亚地区气旋性(反气旋性)环流对应,而7月ISO的强(弱)对应于南亚地区反气旋性(气旋性)环流。6月南亚大气ISO强(弱)对应于南海地区气旋性(反气旋性)环流,而7、8月无论是南亚大气ISO强年还是弱年,南海地区都表现为反气旋性异常环流。从降水来看,夏季6、7月南海大气ISO偏强(弱)年,长江以南大部分为正(负)距平而江淮流域降水基本上为负(正)距平。而8月南海大气ISO强弱年,长江以南与江淮流域这种反相的降水特征并不明显。7月南亚大气ISO强(弱)年,长江以南降水大部分为负(正)距平而江淮流域为正(负)距平,而6月和8月南亚大气ISO的强弱对中国东部降水的影响并不如7月表现明显。  相似文献   
49.
关于《数字地图产品模式》标准的思考   总被引:1,自引:0,他引:1  
苏山舞 《测绘科学》2006,31(1):80-81,89
基于《数字地图产品模式》(以下简称《标准》)研究成果,本文确定了《标准》的目的、编制理由和《标准》的用户;指出了《标准》在相关“参考模型”和“标准体系”中的位置;提出了《标准》的范围;分析了国内外同类标准及相关资料并介绍了其在《标准》中的应用概况;以列出修订前后标准目次和ISO19131草案目录结构对照表的方式,剖析了《标准》研究成果的结构框架;最终得出了《数字地图产品模式》标准的编制已经有了良好的开端和阶段性成果,应当抓紧时间完善成果,使研究成果尽快转化为国家标准的结论。  相似文献   
50.
The influence of intraseasonal oscillation (ISO) on TC genesis over the northwestern Pacific is studied through comparing analyses of the more and less TC years from 1979 to 2006. It is indicated that the ISO strongly affects the TC genesis. In the years for more TC genesis, the ISO is weak and propagates insignificantly in the area to the west of the Philippines, but the ISO is strong in the area to the east of the Philippines and propagates significantly northwestward. In this situation, the Walker cell shifts gradually westward from the tropical western Pacific to the tropical eastern Indian Ocean. Convergent winds appear in the lower atmosphere while divergent winds in the upper atmosphere, suggesting the presence of enhanced ascending flow over the 140-160°E region and a favorable condition for TC genesis. Moreover, in the years for less TC genesis, the ISO gradually becomes stronger in the area to the west of the Philippines and significant eastward propagation prevails from the eastern Indian Ocean to the area around 120°E; the ISO is weak in the area to the east of the Philippines. During these years, the Walker circulation gradually moved eastward, with convergent winds in the upper troposphere and divergent winds in the lower troposphere. Sinking motion was significant, unfavorable for the TC genesis over the Northwestern Pacific.  相似文献   
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