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排序方式: 共有129条查询结果,搜索用时 625 毫秒
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深圳市排污收费系统的开发与研究 总被引:1,自引:0,他引:1
排污收费是环境保护工作中的重要内容,它直接体现了监管的力度和执法的效果。由于这项工作与其他业务部门,如建设项目审批、环境监督、环境监测、环境执法等部门联系密切,因而信息结构复杂。目前在我国投入使用的排污收费管理系统软件大多是FOXPRO数据库,难于实现收费信息共享。基于城市级环境信息管理系统的需求以及目前进行的污染物总量排污收费制度的试点,开发出一套WINDOWS环境采用SYBASE数据库的排污收费管理系统PWSF是十分必要的。 相似文献
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罗伟坚 《中国特种设备安全》2014,(12):36-40
本文分析了特种设备的安全状况、应急救援预案的管理要求和现状,提出了应急救援预案的构成要素及其主要内容,以液化石油气储罐为例阐述了危险源辨识、后果预测以及现场应急处置方法,为企业编制特种设备应急预案提供了参考。 相似文献
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Problem: Speeding-related crashes continue to be a serious problem in the United States. According to the National Highway Traffic Safety Administration, 26% of all fatal crashes in 2017 had speeding as a contributing factor. Method: Vehicle speed data recorded during the Strategic Highway Research Program 2 (SHRP 2) Naturalistic Driving Study were analyzed to identify the frequency of speeding episodes. Up to 100 trips were sampled from 2,910 individual drivers aged 16–64. Vehicle speed data from individual trips were parsed into continuous speeding episodes (SEs) and Free-Flow Episodes (FFEs), which approximated opportunities to speed. Results & Discussion: Driving 10 mph above the posted speed limit (PSL) was common, and 99.8% of drivers had at least one occurrence SE within their trip sample, yielding an average of 2.75 SEs per trip (623,202 SEs in total). The analysis focused on a subset of higher-speed SEs in which the vehicle reached speeds of at least 15 mph above the PSL during the SE (71,113 SEs in total). Average maximum speeds for most higher-speed SEs ranged between 12 mph to 15 mph above the PSL, and most also lasted less than 2 min. Most drivers spent less than 5% of the FFE time speeding, and only a small number of drivers spent more than 10% of the time speeding. There was also a clear trend towards the younger group having higher overall percentages of SE time relative to FFE time. Practical Applications: The methods and measures developed in this study provide the foundation for future analyses to determine if there are different types of speeding that vary in terms of risky characteristics, and further, if certain drivers are more likely to engage in riskier speeding behavior. Identifying higher-risk speeders is an important step for developing countermeasures and strategies targeting drivers that are at greatest risk of speed-related crashes. 相似文献
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Understanding the process of the changing phytoplankton patterns can be particularly useful in water quality improvement and management decisions. However, it is generally not easy to illustrate the interactions between phytoplankton biomass and related environmental variables given their high spatial and temporal heterogeneity. To elucidate relationships between them, in a eutrophic shallow lake, Taihu Lake, relative long-term data set of biotic and abiotic parameters of water quality in the lake were conducted using multivariate statistical analysis within seasonal periodicity. The results indicate that water temperature and total phosphorus (TP) played governing roles in phytoplankton dynamics in most seasons (i.e. temperature in winter, spring and summer; TP in spring, summer and autumn); COD (chemical oxygen demand) and BOD (biological oxygen demand) presented significant positive relationships with phytoplankton biomass in spring, summer and autumn. However, a complex interplay was found between phytoplankton biomass and nitrogen considering significant positive relationships occurring between them in spring and autumn, and conversely negative ones in summer. As the predatory factor, zooplankton presented significant grazing-pressure on phytoplankton biomass during summer in view of negative relationship between them in the season. Significant feedback effects of phytoplankton development were identified in summer and autumn in view that significant relationships were obser,qed between phytoplankton biomass and pH, Trans (transparency of water) and DO. The results indicate that interactions between phyto:plankton biomass and related environmental variables are highly sensitive to seasonal periodicity, which improves understanding of different roles of biotic and abiotic variables upon phytoplankton variability, and hence, advances management methods for eutrophic lakes. 相似文献
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水产养殖对水生生态系统中汞甲基化影响研究进展 总被引:3,自引:0,他引:3
水产养殖造成的水体富营养化不仅导致有机质增加,而且致使很多水体理化参数发生变化,包括水中溶解氧下降、沉积物中有机质和硫酸盐、硫化氢的增加、pH值的下降、生物和微生物群落的破坏等.然而,目前国内外在这方面的研究极少,水产养殖对水体汞甲基化的影响尚不清楚,对其进行深入的研究,并提出合理利用和开发水资源的科学建议具有重要的现实意义. 相似文献
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组织滴虫病是近年来国内养禽业中出现的一个新问题。作者根据国内外资料,对本病的病原、流行特点和症状、诊断进行了较为详细的评述,并提出了科学的饲养管理措施和防治方法。 相似文献