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91.
利用面向对象技术、多线程技术和动态链接技术在嵌入式操作Windows CE上开发了移动环境监测系统。介绍了基于实时嵌入式操作的移动环境监测系统的设计原理、系统框架及关键技术。指出在嵌入式计算机上实现移动环境监测,既可以进行在线环境监测,也可以减少开发的费用和硬件投资。该系统的特点是集成度高,体积小,反应速度快,智能化高,稳定性好和可靠性强。 相似文献
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94.
灰色模型在确定关键污染因子中的应用 总被引:1,自引:2,他引:1
将灰色模型引入水环境质量评价中 ,通过对某个时间段内污染物原始监测数据的灰色处理 ,从动态演变中找出关键因子 ,客观地判定各污染因子所起的作用 ,并对各因子在下一个时间段的发展趋势作出判断 ,增加了评价的准确性。经过实例运用分析表明 ,该方法物理意义明确 ,简便易用 相似文献
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96.
氨基酸法现场快速测定废水中的磷酸盐 总被引:3,自引:0,他引:3
通过磷酸盐与钼酸盐、氨基酸反应使样品呈淡蓝色,讨论了在事故现场快速测定水中磷的方法。试验表明方法灵敏,操作简单快速。检测范围0~15mg/L。 相似文献
97.
Bass B Economou V Lee CK Perks T Smith SA Yip Q 《Environmental monitoring and assessment》2003,85(2):199-219
Indoor environmental health is now recognized as an important factor in preventing respiratory health problems in the United States. It is also a concern in Canada due to the amount of time that Canadians spend indoors because of cold weather and the potential for increased time indoors during the summer if theclimate warms. The negative health effects are often labeled assick building syndrome, but diagnosing a building or itsoccupants as sick is complicated by the variety of symptoms, thepresence of chronic versus acute symptoms and social andpsychological (socio-psychological) factors that may reduce theeffectiveness of an engineering solution. As a case study, thecontribution of various factors to indoor environmental health,in three buildings at the University of Toronto, was examinedusing five different methods. The results indicate that theinhabitants of the buildings consider features other than airquality in considering building health such as design,maintenance, funding cuts and socio-psychological factors. 相似文献
98.
Longhurst J 《Environmental monitoring and assessment》2005,111(1-3):27-42
Denmark has a long tradition of monitoring the aquatic environment. Previous monitoring has mainly focused on loss of nutrients
and subsequent impacts on the biological structure in lakes and coastal areas. However, as part of the third Action Plan for
the Aquatic Environment more emphasis has been put on stream ecology. The present paper describes background, strategy and
content of the new NOVANA stream programme, which will run for the period 2004–2009. The new programme will encompass more
than 800 stations covering all stream types in Denmark and monitoring will include three biological quality elements (macrophytes,
macroinvertebrates and fish) as well as physico-chemical features and hydromorphological elements. In addition, the new programme
integrates monitoring of elements both in the stream itself and in the riparian zone. Compliance with important European Commission
Directives such as the Water Framework Directive and the Habitat Directive is discussed. 相似文献
99.
Graef F Schmidt G Schröder W Stachow U 《Environmental monitoring and assessment》2005,108(1-3):189-203
A representative environmental monitoring network at the regional scale cannot use raster-based or random sampling designs, but requires a stratified sampling procedure integrating different information layers, and it has to occur in ecologically differing homogeneous regions (ecoregions). These we have determined using a set of spatial strata with ecological variables which we analysed with classification and regression trees (CART). We present a framework for environmental monitoring, that covers different scales, and we transfer the framework to a potential GMO (genetically modified organisms) monitoring network. We use ecoregion and other environmental strata together with existing environmental monitoring networks to determine GMO monitoring sites more precisely. 相似文献
100.
Landsat 7s recent malfunctioning will result in significant gaps in long-term satellite monitoring of Earth, affecting not only the research of the Earth science community but also conservation users of these data. To determine whether or how important Landsat monitoring is for conservation and natural resource management, we reviewed the Landsat programs history with special emphasis on the development of user groups. We also conducted a bibliographic search to determine the extent to which conservation research has been based on Landsat data. Conservation biologists were not an early user group of Landsat data because a) biologists lacked technical capacity – computers and software – to analyze these data; b) Landsats 1980s commercialization rendered images too costly for biologists budgets; and c) the broad-scale disciplines of conservation biology and landscape ecology did not develop until the mid-to-late 1980s. All these conditions had changed by the 1990s and Landsat imagery became an important tool for conservation biology. Satellite monitoring and Landsat continuity are mandated by the Land Remote Sensing Act of 1992. This legislation leaves open commercial options. However, past experiments with commercial operations were neither viable nor economical, and severely reduced the quality of monitoring, archiving and data access for academia and the public. Future satellite monitoring programs are essential for conservation and natural resource management, must provide continuity with Landsat, and should be government operated. 相似文献