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Due to pollution caused by the expansion of human activities and economic development, water quality has gradually deteriorated
in many areas of the world. Therefore, analysis of water quality becomes one of the most essential issues of modern civilization.
Integrated interdisciplinary modeling techniques, providing reliable, efficient, and accurate representation of the complex
phenomenon of water quality, have gained attention in recent years. With the ability to deal with both numeric and nominal
information, and express knowledge in a rule-based form, the Rough Set Theory (RST) has been successfully employed in many
fields. However, the application of RST has not been widely investigated in water quality analysis. The reducts generated
by RST models become very time-consuming as the size of the problem increases. Using multinomial logistics regression (MLR)
techniques to provide reducts of RST models, this investigation develops a hybrid Multinomial Logistic Regression and Rough
Set Theory (MLRRST) model to analyze relations between degrees of water pollution and environmental factors in Taiwan. Empirical
results indicate that the MLRRST model could analyze water qualities efficiently and accurately, and yield decision rules
for the staff of water quality management. Thus, the proposed model is a promising and helpful scheme in analyzing water quality. 相似文献
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由集对分析理论导出了水环境质量评价的新模型,将水质实测指标与分类标准作为集对,通过对评价级别和实测数据归一化后,得到模型的平均联系度,建立了水质评价的集对分析模型。并以九寨沟五彩池水环境质量为例,选取具有代表性的CODcr、DO、NH3-N、TP、粪大肠菌群五项指标及其对应的Ⅰ至Ⅴ类水质标准的取值范围构造集对,建立了水质评价集对模型,计算出平均联系度,得出该九寨沟五彩池水环境质量属于Ⅰ级。实例研究表明:运用集对分析模型评价水环境质量,评价结果符合客观实际,方法是可行的,具有较好的实用性。 相似文献
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针对标准集对分析存在同异反评语细化问题,对传统模型进行改进。在水质权重确定过程中,因单一采用主观确权法或客观确权法均存在缺陷,提出综合确定权值的思路。选用改进后的AHP法主观确权和熵权系数法客观确权,然后依据最小鉴别信息原理进行综合确权,提高了权重确定的科学性。将新方法运用在大伙房水库水质评价中,将评价结果与基于模糊评价法、BP神经网络法的评价结果进行比较。结果表明新方法能更贴近实际,反映水质特征,具有良好的应用前景。 相似文献
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在分析水资源承载力构成要素的基础上,遵循科学性、层次性、可操作性和目标导向性原则,构建了水资源承载力评价指标体系,并将组合赋权法和集对分析法相结合,对三江平原及各分区水资源承载力进行评价。结果表明:研究区整体水资源承载力处于"中等"水平;7个县市中,七台河市与穆棱市水资源承载力为Ⅱ级,处于"较好"水平,鸡西市、鹤岗市、双鸭山市、佳木斯市与依兰县处于"中等"水平。 相似文献
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针对水资源安全评价指标的不确定性,提出了基于集对分析理论的水资源安全综合评价方法,用联系度诠释有关不确定性的因素,充分展现了研究问题中所包含的所有信息.结果表明,贵阳市水资源处于安全状态,六盘水市、黔南州、黔东南州和铜仁地区处于临界安全状态,其余4个地区处于不安全状态. 相似文献
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区域水资源可持续利用评价是区域资源-经济-社会可持续发展战略研究的核心问题之一,目前提出的评价模型大多存在结构复杂、不易操作等问题。为此,文章提出基于集对分析的水资源可持续利用评价模型。实例研究结果表明,在区域各种自然资源可持续利用系统评价中均具有推广应用价值。 相似文献
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Antecedent physical factors are used in calculations, which endowed set pair analysis with predictive abilities. Set pair analysis can make predictions based on calculations using antecedent physical factors. In this study, the fitted value $ {\widehat{Y}}_1 $ based on set pair analysis agreed with the actual value of the average annual discharge grade at Yamadu Station, which showed that the prediction was valid. It’s predicted that the average annual discharge at Yamadu Station in 1975 was a dry year, i.e. y?<?385 m3/s, while the actual average annual discharge at Yamadu Station in 1975 was 301 m3/s, which confirmed the prediction that it was a dry year. Three physical factors were not processed using set pair analysis so they could be compared with the calculated results. These factors were used directly to establish a regression equation for the average annual discharge grade and obtained a fitted value of $ {\widehat{Y}}_3 $ for the average annual discharge grade at Yamadu Station during 1953–1974. It’s known that the prediction of the average annual discharge grade for 1966 using a regression equation derived from the data differed from the actual situation, thereby indicating that set pair analysis can be used to improve the accuracy of predictions. 相似文献
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集对分析是处理不确定性问题的新方法,它通过联系度展示了研究对象间关系的详细结构。方法原理简单,使用方便,能解决很多实际水文水资源问题。简要介绍了集对分析的基本原理,重点分析了集对分析在水文水资源分析计算、预测和评价中的应用研究进展,展望了集对分析在水文水资源领域的研究目标、内容和拟解决的关键问题。 相似文献
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传统的模糊集分析法进行汛期分期过程中,在汛期区间与阈值的确定方面存在主观性较强的问题,同时该方法只能考虑单一的因素,针对这些问题提出改进模糊集分析法。使用变异系数法计算指标权重,用每个旬的所有指标加权组合成为一个综合指标,以代替原来的单一指标;使用模糊集合分析法计算隶属度,划分汛期与非汛期,最后在汛期区间内,使用均值变点分析法寻找变点,并以此进行汛期分期。改进的模糊集分析法的分期结果与数理统计法、传统模糊集合分析法的汛期分期结果大体一致,说明提出的改进模糊集分析法适用性强。 相似文献
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为合理评价湖北省水资源态势,在系统考虑湖北省水资源特点和实际情况的基础上,同时遵循代表性、科学性、可操作性和系统性等指标体系构建原则,构建了基于驱动力-压力-状态-影响-响应(DPSIR)概念框架的湖北省水资源评价指标体系,并将熵权法与模糊集对分析法相结合,建立了水资源评价模型,对湖北省2008-2016年水资源状态进行了定量评价。研究结果表明:(1)2008-2016年湖北省水资源状态呈现出波动式升高的趋势,研究结果表明近9年间湖北省的水资源状态良好;(2)从水资源DPSIR评价结果可以看出,研究时段内水资源影响和水资源响应是影响湖北省水资源状况的最重要因素。 相似文献
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