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951.
基于OPC的煤矿安全监测系统的设计   总被引:1,自引:0,他引:1  
针对控制网接入上层管理网难和各个安全监控系统互不兼容的问题,设计了一种基于OPC技术的煤矿安全监测系统。通过各种工控设备配有的OPC服务器,与矿井下各安全监控分站建立通讯关系,并遵循统一的OPC协议,将采集的井下实时状况数据整合到SQL Server2005关系数据库中,借助工业以太网上传给企业的安全管理平台,经过数据分析和图表显示,可以快捷直观地了解井下具体情况,同时也可以通过网页W eb在整个煤矿企业内部办公网络中进行发布,让安全信息得到全矿的分享。这里以煤矿注浆监测系统为例,重点介绍了利用OPC技术实现上层网与终端注浆监控网通讯的方案。  相似文献   
952.
为进一步提升北京市科技攻关能力,推进北京市科技创新体系建设,由北京市劳动保护科学研究所牵头,联合有关单位共同申请的《北京市职业安全健康重点实验室》,将成为北京市首个多方合作、优势互补、强强联合的典范。该实验室对于全面提升我国和北京市职业安全健康科技创新能力,加快科研成果的转化和培养新型复合型职业安健康领域的科研人才,以及在引领相关领域科研模式创新发展等方面将发挥重要的作用。  相似文献   
953.
试论石油企业环境监测机构的现状及发展   总被引:1,自引:0,他引:1  
文章分析了石油企业环境监测机构的现状,明确了石油企业环境监测机构的工作立足点。同时,在中国石油天然气集团公司创建综合性国际能源公司、深化HSE体系推进的大背景下,对各油气田企业环境监测机构的未来与发展进行探讨,并结合实际提出较为合理的发展设想。  相似文献   
954.
“十一五”期间辽河铁岭段及支流水质变化趋势   总被引:2,自引:0,他引:2  
用Daniel的Spearman秩相关系数法对辽河铁岭段及支流在"十一五"期间水质进行趋势检验,确定各监测断面超标污染物及综合污染指数上升或下降趋势的显著性,结合铁岭市"十一五"期间的污染治理措施,分析各项污染物产生变化的原因,提出了今后的工作方向,为进一步加强环境管理提供了依据。  相似文献   
955.
淮河流域某地区地下水污染健康风险评价   总被引:2,自引:0,他引:2  
杨莉霞  王琳  姜朴  徐顺清 《环境化学》2011,30(9):1599-1603
为研究淮河流域下游某地区地下水中污染物对人体产生的潜在健康危害风险,对该地区的水质进行了监测分析,并采用美国环境保护署(U.S.EPA)推荐的健康风险评价模型对该地区地下水中污染物所引起的健康风险进行了评价.结果表明,所监测的污染物浓度都在生活饮用水卫生标准(GB 5749—2006)和地下水质量标准(GB/T 148...  相似文献   
956.
957.
Saad, David A., Gregory E. Schwarz, Dale M. Robertson, and Nathaniel L. Booth, 2011. A Multi‐Agency Nutrient Dataset Used to Estimate Loads, Improve Monitoring Design, and Calibrate Regional Nutrient SPARROW Models. Journal of the American Water Resources Association (JAWRA) 47(5):933‐949. DOI: 10.1111/j.1752‐1688. 2011.00575.x Abstract: Stream‐loading information was compiled from federal, state, and local agencies, and selected universities as part of an effort to develop regional SPAtially Referenced Regressions On Watershed attributes (SPARROW) models to help describe the distribution, sources, and transport of nutrients in streams throughout much of the United States. After screening, 2,739 sites, sampled by 73 agencies, were identified as having suitable data for calculating long‐term mean annual nutrient loads required for SPARROW model calibration. These sites had a wide range in nutrient concentrations, loads, and yields, and environmental characteristics in their basins. An analysis of the accuracy in load estimates relative to site attributes indicated that accuracy in loads improve with increases in the number of observations, the proportion of uncensored data, and the variability in flow on observation days, whereas accuracy declines with increases in the root mean square error of the water‐quality model, the flow‐bias ratio, the number of days between samples, the variability in daily streamflow for the prediction period, and if the load estimate has been detrended. Based on compiled data, all areas of the country had recent declines in the number of sites with sufficient water‐quality data to compute accurate annual loads and support regional modeling analyses. These declines were caused by decreases in the number of sites being sampled and data not being entered in readily accessible databases.  相似文献   
958.
Two computational methods were applied to classification of movement patterns of zebrafish (Danio rerio) to elucidate Markov processes in behavioral changes before and after treatment of formaldehyde (0.1 mg/L) in semi-natural conditions. The complex data of the movement tracks were initially classified by the Self-organizing map (SOM) to present different behavioral states of test individuals. Transition probabilities between behavioral states were further evaluated to fit Markov processes by using the hidden Markov model (HMM). Emission transition probability was also obtained from the observed variables (i.e., speed) for training with the HMM. Experimental transition and emission probability matrices were successfully estimated with the HMM for recognizing sequences of behavioral states with accuracy rates in acceptable ranges at central and boundary zones before (77.3-81.2%) and after (70.1-76.5%) treatment. A heuristic algorithm and a Markov model were efficiently combined to analyze movement patterns and could be a means of in situ behavioral monitoring tool.  相似文献   
959.
Knowledge gain and behavioral change in citizen-science programs   总被引:1,自引:0,他引:1  
Citizen-science programs are often touted as useful for advancing conservation literacy, scientific knowledge, and increasing scientific-reasoning skills among the public. Guidelines for collaboration among scientists and the public are lacking and the extent to which these citizen-science initiatives change behavior is relatively unstudied. Over two years, we studied 82 participants in a three-day program that included education about non-native invasive plants and collection of data on the occurrence of those plants. Volunteers were given background knowledge about invasive plant ecology and trained on a specific protocol for collecting invasive plant data. They then collected data and later gathered as a group to analyze data and discuss responsible environmental behavior with respect to invasive plants. We tested whether participants without experience in plant identification and with little knowledge of invasive plants increased their knowledge of invasive species ecology, participation increased knowledge of scientific methods, and participation affected behavior. Knowledge of invasive plants increased on average 24%, but participation was insufficient to increase understanding of how scientific research is conducted. Participants reported increased ability to recognize invasive plants and increased awareness of effects of invasive plants on the environment, but this translated into little change in behavior regarding invasive plants. Potential conflicts between scientific goals, educational goals, and the motivation of participants must be considered during program design.  相似文献   
960.
北京建成区道路绿化空间结构和行道树健康状况   总被引:2,自引:0,他引:2  
采用实地普查测量方法,定量研究了北京建成区188条道路行道树的树种结构、径级分布、立木层次和健康状况。结果表明,国槐(Sophora japonica)、毛白杨(Populus alba)、银杏(Ginkgo biloba)是建成区主要行道树种,使用量分别占研究区树木总株数的54.7%、13.7%和7.4%。建成区树木...  相似文献   
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