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121.
根据2000--2012年全国城镇生活污水排放量数据,建立了相应的GM(1,1)模型和预测函数。通过后验差检验等对预测函数进行了评估,并对2013--2017年城镇生活污水排放量进行了预测,结果表明,2013--2017年全国城镇生活污水的排放量逐年增加,呈上升趋势,从2013年的477.2736亿t上升到2017年的624.1022亿t;灰色预测模型和方法简单易用,利用较少的数据即可进行精度较高的预测。  相似文献   
122.
为掌握我国煤炭行业整体安全生产状况,构建动态无偏灰色马尔科夫模型,通过处理我国1999—2008年度煤矿百万吨死亡率数据,对2009—2011年度煤矿百万吨死亡率数据进行预测。用无偏灰色GM(1,1)模型代替传统灰色GM(1,1)模型,拟合得到煤矿百万吨死亡率数据的变化趋势,在此基础上应用马尔科夫模型进行预测,并在每一次预测中更新原始数据,最后对预测结果进行对比分析。计算结果表明:动态无偏灰色马尔科夫模型既能消除传统灰色GM(1,1)模型的固有偏差,又能提高预测精度尤其是中长期预测精度。其中,平均绝对误差为3.35%,平均相对误差为3.85%,均低于传统灰色GM(1,1)模型和一般灰色马尔科夫模型。动态无偏灰色马尔科夫模型对于煤矿百万吨死亡率数据的平均预测精度超过96%。  相似文献   
123.
基于多因素灰色预测模型的生活污水量预测研究   总被引:1,自引:0,他引:1  
生活污水作为城市水环境的主要污染源,进行生活污水排放量的预测是十分必要的.污水排放量预测方法有多种,不同的方法有各自不同的特点.为提高预测精度,采用灰色预测与多元线性回归相结合的方法,综合各种因素建立多因素灰色预测模型.并以人口和人均纯收入作为影响因素,将该模型应用于苏州横泾街道生活污水排放量的趋势预测中.结果表明:该模型能反映系统的实际情况,建模精度高,平均相对误差只有0.069 8%,值得在污水排放预测中推广应用.  相似文献   
124.
用MATLAB语言建立GM(1,1)模型,以湘江株洲段2003年-2008年氨氮监测值为基础,预测了湘江株洲段2003年-2015年氨氮年平均浓度。所建模型,经精度检验符合预测规律,具有一定的有效性、可行性和适应性。结果表明,建立的GM(1,1)模型精度较高,预测结果与实际监测浓度接近。氨氮年平均浓度呈下降的趋势。  相似文献   
125.
This study aims to recognize and select the appropriate strategy for implementing green manufacturing (GM) in Indian manufacturing industry by developing an instrument which could measure the progress of an organization towards the GM philosophy. This study identifies and analyses the key enablers behind the successful achievement of environmental sustainability in Indian manufacturing industry. Based on extensive literature review and discussions with experts, the critical success factors (CSFs) of GM have been identified. After examining the internal consistency of enablers, weightage is identified for finalizing the priority by analytical hierarchical process (AHP). The pairwise comparison method of AHP identified that top management commitment, green procurement practices and societal concern for protection of natural environment art the most important enablers, and competitiveness and availability of clean technology have comparatively less importance for the studied manufacturing industries. The purpose of this paper is to rank the enablers on identified weightage and develop the framework for offering the useful insights and guides about how industries should link CSFs of GM to improve the environmental and operational performance.  相似文献   
126.
以黑龙江省生态环境监测网监测结果为基础,总结归纳了"十三五"期间黑龙江省生态环境质量变化特征,并采用随机森林和GM(1,1)预测模型对"十四五"期间黑龙江省生态环境质量状况进行了预测。结果表明:"十三五"期间,黑龙江省环境空气、水环境和声环境质量全面好转。其中,环境空气主要污染物PM2.5、PM10、SO2、NO2和CO的年均质量浓度均呈现出明显下降的趋势,"哈大绥"重点区域PM10、SO2、NO2和CO年均质量浓度呈现下降趋势。地表水水质总体呈波动变化趋势,水质状况均为轻度污染。"十四五"期间,黑龙江省生态环境质量将处于稳中向好的趋势。环境空气主要污染物及地表水主要污染指标年均质量浓度均呈现明显的下降趋势,道路交通声环境质量也将得到进一步改善。  相似文献   
127.
Exposure to endocrine disrupting chemicals such as bisphenol A (BPA) and phthalates is prevalent among children and adolescents, but little is known regarding important sources of exposure at these sensitive life stages. In this study, we measured urinary concentrations of BPA and nine phthalate metabolites in 108 Mexican children aged 8–13 years. Associations of age, time of day, and questionnaire items on external environment, water use, and food container use with specific gravity-corrected urinary concentrations were assessed, as were questionnaire items concerning the use of 17 personal care products in the past 48-h. As a secondary aim, third trimester urinary concentrations were measured in 99 mothers of these children, and the relationship between specific gravity-corrected urinary concentrations at these two time points was explored. After adjusting for potential confounding by other personal care product use in the past 48-h, there were statistically significant (< 0.05) positive associations in boys for cologne/perfume use and monoethyl phthalate (MEP), mono(3-carboxypropyl) phthalate (MCPP), mono(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP), and mono(2-ethyl-5-oxohexyl) phthalate (MEOHP), and in girls for colored cosmetics use and mono-n-butyl phthalate (MBP), mono(2-ethylhexyl) phthalate (MEHP), MEHHP, MEOHP, and mono(2-ethyl-5-carboxypentyl) phthalate (MECPP), conditioner use and MEP, deodorant use and MEP, and other hair products use and MBP. There was a statistically significant positive trend for the number of personal care products used in the past 48-h and log-MEP in girls. However, there were no statistically significant associations between the analytes and the other questionnaire items and there were no strong correlations between the analytes measured during the third trimester and at 8–13 years of age. We demonstrated that personal care product use is associated with exposure to multiple phthalates in children. Due to rapid development, children may be susceptible to impacts from exposure to endocrine disrupting chemicals; thus, reduced or delayed use of certain personal care products among children may be warranted.  相似文献   
128.
环境振动的灰色预测模型   总被引:3,自引:0,他引:3  
利用GIM(1)的非时序直接建模法预测研究建筑施工的环境振动 ,并将GIM(1)模型与GM (1,1)模型进行比较分析 ,结果表明GIM(1)模型的拟合精度优良 ,对原始资料中白化信息的利用更加丰富 ,拓宽了GIM (1)模型在环境科学领域中的应用范围  相似文献   
129.
According to EC regulations the deliberate release of genetically modified (GM) crops into the agro-environment needs to be accompanied by environmental monitoring to detect potential adverse effects, e.g.unacceptable levels of gene flow from GM to non-GM crops, or adverse effects on single species or species groups thus reducing biodiversity. There is, however, considerable scientific and public debate on how GM crops should be monitored with sufficient accuracy, discussing questions of potential adverse effects, agro-environmental variables or indicators to be monitored and respective detection methods; Another basic component, the appropriate number and location of monitoring sites, is hardly considered. Currently, no consistent GM crop monitoring approach combines these components systematically. This study focuses on and integrates spatial agro-environmental aspects at a landscape level in order to design monitoring networks. Based on examples of environmental variables associated with the cropping of Bt-Maize (Zea maize L.), herbicide-tolerant (HT) winter oilseed rape (Brassica napus L.), HT sugar beet (Beta vulgaris L.), and starch-modified potato (Solanum tuberosum L.), we develop a transferable framework and assessment scheme that comprises anticipated adverse environmental effects, variables to be measured and monitoring methods.These we integrate with a rule-based GIS (geographic information system) analysis, applying widely available spatial area and point information from existing environmental networks. This is used todevelop scenarios with optimised regional GM crop monitoring networks.  相似文献   
130.
基于MATLAB的湘江流域工业固体废物灰色预测   总被引:3,自引:0,他引:3  
对灰色预测原理及其建模步骤作了系统介绍。借助MATLAB软件建立等维灰数递补残差修正动态模型预测湘江流域未来10年工业固体废物年产量,以期为湘江流域今后工业固体废物的管理、污染防治工作提供科学依据。结果表明:(1)用此模型进行预测,相对误差均在5%以下,预测精度较高,取得了较理想的预测效果;(2)湘江流域未来10年工业固体废物年产量预测值呈指数趋势增长,年增长率为8%~12%,到2016年湘江流域工业固体废物年产量预计将达到7645.01万t。  相似文献   
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