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171.
用BP神经网络模型定量估算石化企业炼油废水处理中的VOCs   总被引:1,自引:0,他引:1  
将BP神经网络理论引入石化企业炼油厂废水处理中的VOCs挥发量估算。在分析影响VOCs挥发因素的基础上,利用基于MATLAB神经网络工具箱的图形用户界面GUI,建立了石化企业炼油废水处理中VOCs挥发量估算的BP神经网络模型。用该模型对样本集进行了学习训练和仿真测试,并将训练好的神经网络应用于相关实例的估算。结果表明,应用BP神经网络方法进行石化企业炼油废水处理中VOCs挥发量估算结果与美国环保局推荐软件WATER9的计算结果误差在1.49%~17.46%之间,为石化企业炼油废水处理中VOCs挥发量估算提供了一种较为可靠的方法。  相似文献   
172.
由于污染排放存在时空与行业"热点"(hot spots)问题,针对非均匀污染物建立跨区域排污权交易体系具有一定困难。基于一种新的污染外部性度量系数,本文对传统的达标检测方法进行了改进,在此改进达标检测法上构建的跨区域排污权交易体系,能够在简化交易机制和管理工作的同时较好地解决"热点"问题,在社会总产出和总排污量不变的情况下实现社会福利的帕累托改进。  相似文献   
173.
我国工业“三废”的环境库兹涅茨曲线实证研究   总被引:2,自引:0,他引:2  
选取我国1996~2008年共13年的人均GDP与工业"三废"排放量的统计数据,借助SPSS系统软件,建立计量经济学模型,分析了工业"三废"排放量的环境库兹涅茨曲线特征及其成因。研究发现:我国工业固体废物排放量的环境库兹涅茨曲线呈现出一条递增的直线;工业废水排放量的环境库兹涅茨曲线呈现出一条"倒N型"("U型"+"倒U型")曲线;工业废气排放量环境库兹涅茨曲线近似"倒U型"曲线的左半段。也就是说,除工业废水排放量回归曲线出现拐点外,工业固体废物产生量与工业废气排放量仍处于上升期。  相似文献   
174.
"十二五"时期,随着大连全域城市化快速推进,经济社会持续快速发展,资源消耗量、污染产生量迅速增加,给资源环境带来极大的挑战。结合大连市的环境现实,提出在"十二五"期间,大连市应坚持绿色、低碳发展理念,以生态市建设和节能减排为重点,健全激励和约束机制,加大环境保护力度,提高生态文明水平,建设环境优美、风光秀丽的生态宜居城市。  相似文献   
175.
以镇江为例,通过对“十一五”期间镇江生态环境变动趋势的分析,认为产业结构偏重、能源消费结构不合理、环保资金缺乏、城市化和工业化带来新的污染、城市污染转移到农村以及政府考核体系不科学和传统GDP制度有缺陷是造成环境污染的主要原因。建议采取综合治理措施,有针对性地解决环境污染问题,促进镇江经济社会的可持续发展。  相似文献   
176.
Volunteer involvement in biological surveys is becoming common in conservation and ecology, prompting questions on the quality of data collected in such surveys. In a systematic review of the peer‐reviewed literature on the quality of data collected by volunteers, we examined the characteristics of volunteers (e.g., age, prior knowledge) and projects (e.g., systematic vs. opportunistic monitoring schemes) that affect data quality with regards to standardization of sampling, accuracy and precision of data collection, spatial and temporal representation of data, and sample size. Most studies (70%, n = 71) focused on the act of data collection. The majority of assessments of volunteer characteristics (58%, n = 93) examined the effect of prior knowledge and experience on quality of the data collected, often by comparing volunteers with experts or professionals, who were usually assumed to collect higher quality data. However, when both groups’ data were compared with the same accuracy standard, professional data were more accurate in only 4 of 7 cases. The few studies that measured precision of volunteer and professional data did not conclusively show that professional data were less variable than volunteer data. To improve data quality, studies recommended changes to survey protocols, volunteer training, statistical analyses, and project structure (e.g., volunteer recruitment and retention).  相似文献   
177.
One-on-one interviews and focus-group meetings were held at 20 organizations that had implemented a behavior-based safety (BBS) process in order to find reasons for program success/failures. A total of 31 focus groups gave 629 answers to six different questions. A content analysis of these responses uncovered critical information for understanding what employees are looking for in a BBS program. A perception survey administered to individual employees (n = 701) at these organizations measured a variety of variables identified in prior research to influence success in safety efforts. The survey data showed five variables to be significantly predictive of employee involvement in a BBS process: 1) perceptions that BBS training was effective; 2) trust in management abilities; 3) accountability for BBS through performance appraisals; 4) whether or not one had received education in BBS; and 5) tenure with the organization. Also, employees in organizations mandating employee participation in a BBS process (n=8 companies) reported significantly higher levels of: (a) involvement; (b) trust in management; (c) trust in coworkers; and (d) satisfaction with BBS training than did employees whose process was completely voluntary (n = 12 companies). In addition, employees in mandatory processes reported significantly greater frequency of giving and receiving positive behavior-based feedback.  相似文献   
178.
The article examines whether agricultural training boosted technology adoption and productivity was a key issue that was concerned by policymakers and researchers. Thus, impacts of fertilizer application training programs on the adoption of formula fertilization techniques and agricultural productivity were analyzed by using the survey data of 691 apple growers. The results indicated that: (i) compared with farmers who did not participate in fertilizer application training programs, the probability of the adoption of formula fertilization techniques was significantly increased by 256.1% for farmers who participated in fertilizer application training programs; (ii) fertilizer application training programs boosted the adoption of formula fertilization techniques via influencing farmers' cognition and willingness; (iii) yield was significantly increased by 14.3% at the 5% level through participating in fertilizer application training programs, and fertilizer application training programs improved agricultural productivity by means of enhancing the adoption of formula fertilization techniques. This study was conducive to evaluating the effectiveness of agricultural training and boosting agricultural sustainable development.  相似文献   
179.
Sustainable use of military training lands requires understanding and prediction of the effects of military vehicles on vegetation. We examined the initial impacts of an 8-wheeled, light armored vehicle (LAV) on grassland vegetation at Fort Lewis, Washington. The LAV drove replicate spiral paths at two starting velocities, 10.3 and 5.1 m s(-1). The disturbed width (width of ground impacted by the tires) increased as turning radius decreased, but was unaffected by vehicle velocity. An inverse-exponential model predicted disturbed width (r(2)=0.68) at all turning radii for both velocities combined. In low-velocity spirals, and for straight tracking (turning radius>40 m) and moderate turns (radius 20-40 m) in high-velocity spirals, all vegetation damage was imprint (plants flattened by wheels). During sharp (radius <20 m), high-velocity turns, most or all of the disturbed width was scraped free of surface vegetation and soil, which was piled to the outside of each tire track. Total plant cover (all species) was not affected by track curvature in low-velocity spirals, but decreased in the order straight tracking>moderate turns>sharp turns in high-velocity spirals. In low-velocity spirals, post-tracking cover of several plant growth forms (non-native species, perennial species, sod-forming grasses) was similar to pre-tracking cover, but in high-velocity spirals, post-tracking cover of these growth forms decreased in the order straight > or =moderate=sharp. Cover of native species and forbs decreased more in high- than in low-velocity spirals, but was unaffected by curvature. Pre- and post-tracking cover of annual species, bunchgrasses, and shrubs was < or =3%. The most severe vegetation damage caused by operation of wheeled LAVs on grasslands is associated with sharp, high-velocity turns.  相似文献   
180.
详细介绍了美国环境空气监测培训课程设置的方法和结构,分析了其在课程的目标规划、内容设计和指导人员自学方面的主要做法,总结出应从监测人员能力和知识要求角度设定培训目标,以技术性实用性内容为主设计课程环节,将指导支持人员自学摆在更突出位置。借鉴美国经验,文章对探索我国环境空气监测培训的课程设置提出了具体建议。  相似文献   
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