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1.
Modelling daily multivariate pollutant data at multiple sites   总被引:7,自引:1,他引:6  
Summary. This paper considers the spatiotemporal modelling of four pollutants measured daily at eight monitoring sites in London over a 4-year period. Such multiple-pollutant data sets measured over time at multiple sites within a region of interest are typical. Here, the modelling was carried out to provide the exposure for a study investigating the health effects of air pollution. Alternative objectives include the design problem of the positioning of a new monitoring site, or for regulatory purposes to determine whether environmental standards are being met. In general, analyses are hampered by missing data due, for example, to a particular pollutant not being measured at a site, a monitor being inactive by design (e.g. a 6-day monitoring schedule) or because of an unreliable or faulty monitor. Data of this type are modelled here within a dynamic linear modelling framework, in which the dependences across time, space and pollutants are exploited. Throughout the approach is Bayesian, with implementation via Markov chain Monte Carlo sampling.  相似文献   
2.
Low dose risk estimation via simultaneous statistical inferences   总被引:2,自引:0,他引:2  
Summary.  The paper develops and studies simultaneous confidence bounds that are useful for making low dose inferences in quantitative risk analysis. Application is intended for risk assessment studies where human, animal or ecological data are used to set safe low dose levels of a toxic agent, but where study information is limited to high dose levels of the agent. Methods are derived for estimating simultaneous, one-sided, upper confidence limits on risk for end points measured on a continuous scale. From the simultaneous confidence bounds, lower confidence limits on the dose that is associated with a particular risk (often referred to as a bench-mark dose ) are calculated. An important feature of the simultaneous construction is that any inferences that are based on inverting the simultaneous confidence bounds apply automatically to inverse bounds on the bench-mark dose.  相似文献   
3.
史料是史学研究的基础.但自古以来,由于种种原因,错误的或者事实模糊不清的史料很多,如果不作必要的考证鉴别,很难获得科学的研究成果.造成史料引用致误的原因是多方面的,归结起来主要有:(1)史料本身无误,由于没有正确理解原意或者标点不正确而致误;(2)史料本身无误,由于引用者推断不确而致误;(3)史料内容比较含蓄,由于引用者缺乏深入辨析而致误;(4)没有直接引用原书而致误;(5)因版本不善而造成史料的错误或脱漏;(6)史料本身就有错误.  相似文献   
4.
"城中村"城市化的对策研究   总被引:11,自引:0,他引:11  
随着城市化速度的加快 ,因城市的扩张产生的“城中村”所造成的社会问题日益突出。本文对“城中村”改造过程中遇到的政策和现实问题进行了剖析 ,认为“城中村”改造的主要困难是社会经济政策滞后问题 ,提出了超前调整政策 ,促进“城中村”改造的思路和对策  相似文献   
5.
The development of a Municipal Information System, or currently better known as a local spatial data infrastructure, is considered complex due to the required inter-institutional relationships. In many developing countries Geographical Information Systems (GISs) are introduced but the benefits are modest as no changes take place in technical and organisational structure of organisations. Digital databases and computer-aided design (CAD) maps are mushrooming in great variety within different private and public institutions, municipal organisations and even within single departments and with structures similar to the paper period and thus operating on a stand-alone basis.Many national mapping agencies are not able to provide large-scale digital urban base maps, while the absence or low quality of cadastres makes those basic core data sets unavailable or inaccessible. The result is that duplication and incompatible data are frequently observed and also donor-driven stand-alone projects have a limited impact through the lack of institutional embedding and are not able to mature from the project to the institutional level. However, a positive sign is that there is an increasing awareness among data producers and consumers that investments in the development of digital data sets should be combined to reduce costs and increase benefits from especially GIS, and information and communication technology (ICT) in general.Within Trujillo a long-term vision was developed to make full use of ICT and GIS to modernise all operations of the Municipality to increase the efficiency and effectiveness of its tasks. However, large investments are not feasible due to the very limited municipal budgets. To guarantee the support of the municipal council, short-term results are required. This paper describes three ‘products’ as part of the vision to develop through a step-by-step approach a local spatial data infrastructure for Trujillo.The three, rather different, products are:
1. fiscal cadastre, to increase municipal revenues through property taxation;
2. an ‘environmental atlas’ based on a compatible spatial and attribute data sets from a variety of organisations; and
3. a municipal website with interactive GIS and meta data information.
The paper concludes with some comments on the institutional and political requirements for the successful development of a local spatial data infrastructure and stresses that such an infrastructure is not a product but an incremental development process that will progress only in case such a process is simple, cost effective, user-friendly, and flexible with clear products.Political interest and institutional stability and genuine interest for inter-institutional cooperation will add much to the success of this process.  相似文献   
6.
生态道德教育是一个普遍性的社会伦理问题。生态危机的特征 ,生物共同体的联系以及我国生态环境的现状 ,都客观地要求我们必须注重人与自然界的和谐发展 ,加强全民性的生态道德教育。  相似文献   
7.
在我国,环境审计对于国家审计、内部审计和民间审计来说都是一个新内容。作为环境管理系统的重要组成部分,环境审计具有重大的意义。因此,建立健全环境审计制度,采取切实可行的措施,是环境管理和环境审计的重要任务。  相似文献   
8.
情歌在<诗经>中占有非常重要的地位,其情节形象地再现了古代社会隆重的祭高禖仪式,这一仪式与先民的生殖崇拜密切相关,不仅反映了人们自由、奔放的性爱意识,揭示了人们对生命的热爱和重视,而且寄托着远古民族浓重的宗教情结,从而使<诗经>具有了深厚的人类学价值和深远的文化意蕴.  相似文献   
9.
源于老庄思想的自足、闲适心态 ,是晚年白居易之所以能在洛阳实现身心自然合一的“中隐”生活的心理基础。因为自足 ,才会身心闲适 ,适又以闲为前提条件。其闲适诗中失落了表现社会责任的儒家精神。  相似文献   
10.
企业作为环境污染的主要肇事者, 理应承担起治理环境污染的责任, 由此就会产生相应的环境支出和环境收益, 并因而影响企业的财务状况和经营成果。将环境活动纳入企业会计核算体系, 反映企业对自然资源的消耗和对环境的污染及其治理情况, 披露环境会计信息, 成为传统会计面临的新课题, 本文主要对环境会计信息披露的内容和方式进行探讨  相似文献   
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