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针对污水处理运行过程COD、BOD5、TN和TP实时测量的问题,提出一种基于絮体形态参数的偏最小二乘法模型.采用图像分析技术对污泥絮体形态特征进行提取,基于相关性从提取的形态参数和试验期间的运行参数中选择模型的输入变量,通过偏最小二乘法建立输入变量与4个水质指标的预测关系模型.结果表明,COD、BOD5、TN、TP的交... 相似文献
53.
A government-funded scheme, the UK Climate Change Communications Initiative (UKCCCI), has provided money for organisations to deliver projects that attempt to impact positively on people's attitudes towards climate change. This devolution of communications is a relatively novel approach after previous centralised campaigns. This paper considers what size of target audience is most appropriate for attitude change initiatives. It compares data from a regional UKCCCI project aimed at residents of two counties with a nationally representative dataset. Regional data are also analysed to see if there are differences in attitudes within the two-counties target audience. The study suggests that attitude change interventions must strike a balance between personalisation of information and the higher cost of targeting smaller groups with more specific material. 相似文献
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Shehu Usman Adam Mad Nasir Shamsudin Shaufique F. Sidique Khalid Abdul Rahim Alias Radam 《Journal of Environmental Planning and Management》2015,58(10):1804-1826
The growing popularity of privatized solid waste management service in least developed countries warrants an exploration of factors that are likely to impact on its sustainability. This study takes integrated solid waste management approach by analyzing relevant issues on both market sides. We use a three step theme development sequence to analyze the data obtained on service providers through library research, observations and interviews. This was followed by an opinion survey on the demand side to elicit households’ support for service improvement. Findings show that source-separation issues, government enforcement, market segmentation, financial issues and waste disposal issues are key factors influencing improved service provision. Meanwhile, on the demand side, we found that households are willing to support proposed regulatory improvement in service provision. Thus, we suggest industrial stakeholders to consider the aforementioned supply side issues in designing future service improvements that will take advantage of existing demand side feasibility. 相似文献
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Monika Filipensk Petra Vasatov Lenka Pivokonsk Lenka Cermakov Andrea Gonzalez-Torres Rita K. Henderson Jana Naceradsk Martin Pivokonsky 《环境科学学报(英文版)》2019,31(6):116-127
Coagulation followed by floc separation is a key process for the removal of algal organic matter(AOM) in water treatment. Besides optimizing coagulation parameters,knowledge of the properties of AOM-flocs is essential to maximizing AOM removal.However, the impact of AOM on the floc properties remains unclear. This study investigated how peptides/proteins derived from the cellular organic matter(COM) of the cyanobacterium Microcystis aeruginosa influenced the size, structure, and shape of flocs formed at different shear rates(G). Flocs formed by kaolinite, COM-peptides/proteins and a mixture of the same were studied, and the effect of intermolecular interactions between floc components on floc properties was assessed. The coagulation experiments were performed in a Taylor–Couette reactor, with aluminum(Al) or ferric sulphate(Fe) utilized as coagulants. Image analysis was performed to gauge floc size and obtain data on fractal dimension. It was found that floc properties were affected by the presence of the COM-peptides/proteins and the coagulant used. COM-peptides/proteins increased floc size and porosity and widened floc size distributions. The Fe coagulant produced larger and less compact flocs than Al coagulant. Moreover, the decrease in floc size that occurred in parallel with increase in shear rate was not smooth in progress. A rapid change for the kaolinite-coagulant suspension and two rapid changes for the suspensions containing COM were observed. These were attributed to various intermolecular interactions between floc components participating in coagulation at different G. Based on the results obtained, shear rates suitable for efficient separation of flocs containing COM were suggested. 相似文献
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In this work, an artificial intelligent plastic bottles classification system is proposed, developed and tested. Classifying bottles based on their chemical composition and color is attempted. Near infrared (NIR) reflectance measurements are used to identify bottle composition class. Charged coupled device (CCD) camera with the fusion of quadratic discriminant analysis (QDA) and tree classifiers are used to detect the bottle color.Results have shown that the dip wavelength and average values of the reflective NIR spectrum could be used as features to distinguish between chemical compositions. This resulted in 94.14% classification accuracy. In addition to various preprocessing techniques, the use of principal component analysis algorithm for bottle orientation facilitates the detection of the bottle color avoiding mixing it with the bottle's label or cap. Ninety-two percent color classification accuracy is achieved for clear bottles while 96% is achieved for opaque one, with proposed method. The aggregate classification accuracy of the combined system (i.e. accurate classification of color as well as chemical composition) is 83.48%. 相似文献
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SEM照片孔隙参数提取技术研究 总被引:1,自引:0,他引:1
扫描电镜技术对岩土体微观结构的分析起着越来越重要的作用,从SEM照片中获得定量化的信息参数是众多岩土工程研究者关注的问题。本文以湖南省郴州市王仙岭的黏性土SEM照片的二维和三维分析方法为例来说明SEM照片孔隙参数的提取,并对这两种方法所得结果进行分析比较,结果表明:通常采用的二维及三维分析方法所求得的孔隙率参数值往往偏大;在二维方法中合理选择分割阈值是孔隙率提取的关键,过大过小的阈值都会导致较大的误差;三维方法中需要考虑实际的颗粒形态而不能简单地按照像素值进行三维高程建模。 相似文献
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Tobias Füchslin Mike S. Schäfer Julia Metag 《Environmental Communication: A Journal of Nature and Culture》2018,12(8):1095-1108
ABSTRACTSurveys play a key role in researching public perceptions of and attitudes toward science. Accordingly, there is a breadth of often-used survey instruments available which have also been adopted for segmentation analyses. Even though many of these segmentation solutions are similar in their aims, they often include a large numbers of variables, making it more difficult for other researchers to build on these solutions, as survey time is scarce. Therefore, we demonstrate how a large number of variables that were used for a comprehensive segmentation analysis can be reduced considerably without losing too much information. We develop and test a short survey instrument to segment populations according to their attitudes toward science. Results show that segmentation results can be replicated with over 90% accuracy by reducing the instrument from 20 to 10 variables. This reduction does not significantly affect the predictive power of segment attribution on three dependent variables, which suggests that many segmentation analyses could be similarly optimized, helping researchers save survey time and standardize segmentation analyses more. 相似文献