Q. Fu, Li Peng, Tianxiao Li, Song Cui, Dong Liu, Peiru Yan, Hong-Jin Chen
Snow characteristics were measured in the comprehensive experimental field and the results of a detailed analysis of physical snow properties indicated that snowpack characteristics are affected by a variety of climate parameters. The average liquid water content of snow increased from 0.5% to 3.5%. The bottom snow layer exhibited larger parameter variations than those in the surface and middle layers. The average snow porosity was 72.3% for the entire snowpack, and the changing rate of porosity ranged from 4% to 19% during the accumulation period and from 7% to 25% during the snowmelt period. The porosity of the bottom layer displayed the fastest decline and the largest range. The air temperature, snow temperature and solar radiation showed significant positive correlations with the liquid water content of the snow, and the calculated correlation coefficients were all above 0.9. In addition, relative humidity and temperature were negatively correlated. All meteorological factors studied affected the melting capacity of snow to varying degrees. This study included the design and implementation of snow experiments on bare land under natural conditions as well as measurements of snow parameters in detailed snowpack layers and explained the characteristics of snow parameters combined with meteorological factors.
{"title":"Analysis of characteristic snow parameters and associated factors in a cold region in northeast China","authors":"Q. Fu, Li Peng, Tianxiao Li, Song Cui, Dong Liu, Peiru Yan, Hong-Jin Chen","doi":"10.2166/WS.2018.096","DOIUrl":"https://doi.org/10.2166/WS.2018.096","url":null,"abstract":"Snow characteristics were measured in the comprehensive experimental field and the results of a detailed analysis of physical snow properties indicated that snowpack characteristics are affected by a variety of climate parameters. The average liquid water content of snow increased from 0.5% to 3.5%. The bottom snow layer exhibited larger parameter variations than those in the surface and middle layers. The average snow porosity was 72.3% for the entire snowpack, and the changing rate of porosity ranged from 4% to 19% during the accumulation period and from 7% to 25% during the snowmelt period. The porosity of the bottom layer displayed the fastest decline and the largest range. The air temperature, snow temperature and solar radiation showed significant positive correlations with the liquid water content of the snow, and the calculated correlation coefficients were all above 0.9. In addition, relative humidity and temperature were negatively correlated. All meteorological factors studied affected the melting capacity of snow to varying degrees. This study included the design and implementation of snow experiments on bare land under natural conditions as well as measurements of snow parameters in detailed snowpack layers and explained the characteristics of snow parameters combined with meteorological factors.","PeriodicalId":23573,"journal":{"name":"Water Science & Technology: Water Supply","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80083948","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A new derivative of chitosan functionalized with chloroacyl chloride and 2-(2-aminoethylamino) ethanol was synthesized for the preparation of the magnetic nanocomposite containing Fe 3 O 4 @TiO 2 nanoparticles. Characterizations were done by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and vibrating sample magnetometer (VSM). Nanocomposite was examined for the defluoridation of water, and the effect of contact time, pH, initial fluoride ion concentration, contact time and adsorbent dosage were investigated. Langmuir model showed the best agreement with the experimental data. The maximum adsorption capacity for the fluoride removal from aqueous solutions was 15.385 mg/g at 318 K and pH = 5.0. The adsorption mechanism matches the pseudo-second-order kinetic model with a rate constant ( k 2 ) of 0.68 g/mg·min. Thermodynamics study of the nature of adsorption showed that ΔH and ΔS was 13.767 kJ/mol and 0.066 kJ/mol·K respectively. A mechanism for the fluoride sorption was proposed by considering the electrostatic and hydrogen bonding interactions.
{"title":"Adsorption of fluoride on a chitosan-based magnetic nanocomposite: equilibrium and kinetics studies","authors":"A. Abri, M. Tajbakhsh, A. Sadeghi","doi":"10.2166/WS.2018.050","DOIUrl":"https://doi.org/10.2166/WS.2018.050","url":null,"abstract":"A new derivative of chitosan functionalized with chloroacyl chloride and 2-(2-aminoethylamino) ethanol was synthesized for the preparation of the magnetic nanocomposite containing Fe 3 O 4 @TiO 2 nanoparticles. Characterizations were done by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and vibrating sample magnetometer (VSM). Nanocomposite was examined for the defluoridation of water, and the effect of contact time, pH, initial fluoride ion concentration, contact time and adsorbent dosage were investigated. Langmuir model showed the best agreement with the experimental data. The maximum adsorption capacity for the fluoride removal from aqueous solutions was 15.385 mg/g at 318 K and pH = 5.0. The adsorption mechanism matches the pseudo-second-order kinetic model with a rate constant ( k 2 ) of 0.68 g/mg·min. Thermodynamics study of the nature of adsorption showed that ΔH and ΔS was 13.767 kJ/mol and 0.066 kJ/mol·K respectively. A mechanism for the fluoride sorption was proposed by considering the electrostatic and hydrogen bonding interactions.","PeriodicalId":23573,"journal":{"name":"Water Science & Technology: Water Supply","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74404448","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Amanda Mussared, R. Fabris, J. Vreeburg, J. Jelbart, M. Drikas
Sediment accumulates in distribution systems over time, and can potentially result in dirty water events. The primary origin of these particles in most networks has not been examined. Controlled sediment re-suspension (flushing) events were performed at 10 sites in a drinking water distribution system and repeated 6 months later to observe re-deposition. Different patterns of sediment deposition observed are suspected to be related to particle origin. A large proportion of pipe sediment re-suspended during the first flushing event was composed of iron, most likely arising from corrosion of distribution system infrastructure. This sediment appears to play a role in sheltering microbial cells from secondary disinfection. In this study, a source of particles was identified that may provide an alternate explanation for the presence of iron deposits in systems not dominated by iron pipework.
{"title":"The origin and risks associated with loose deposits in a drinking water distribution system","authors":"Amanda Mussared, R. Fabris, J. Vreeburg, J. Jelbart, M. Drikas","doi":"10.2166/WS.2018.073","DOIUrl":"https://doi.org/10.2166/WS.2018.073","url":null,"abstract":"Sediment accumulates in distribution systems over time, and can potentially result in dirty water events. The primary origin of these particles in most networks has not been examined. Controlled sediment re-suspension (flushing) events were performed at 10 sites in a drinking water distribution system and repeated 6 months later to observe re-deposition. Different patterns of sediment deposition observed are suspected to be related to particle origin. A large proportion of pipe sediment re-suspended during the first flushing event was composed of iron, most likely arising from corrosion of distribution system infrastructure. This sediment appears to play a role in sheltering microbial cells from secondary disinfection. In this study, a source of particles was identified that may provide an alternate explanation for the presence of iron deposits in systems not dominated by iron pipework.","PeriodicalId":23573,"journal":{"name":"Water Science & Technology: Water Supply","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85428321","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This paper presents the results of failure rate prediction by means of support vector machines (SVM) – a non-parametric regression method. A hyperplane is used to divide the whole area in such a way that objects of different affiliation are separated from one another. The number of support vector determines the complexity of the relations between dependent and independent variables. The calculations were performed using Statistical 12.0. Operational data (provided by the Water Utility) for one selected zone of the water supply system for the period 2008–2014 were used for forecasting. The whole data set (in which data on distribution pipes were distinguished from those on house connections) for the years 2008–2014 was randomly divided into two subsets: a training subset – 75% (5 years) and a testing subset – 25% (2 years). Dependent variables ( λ r for the distribution pipes and λ p for the house connections) were forecasted using independent variables (the total length – L r and L p and number of failures – N r and N p of the distribution pipes and the house connections, respectively). Four kinds of kernel functions: linear, polynomial, sigmoidal and radial basis functions were applied. The SVM model based on the linear kernel function was found to be optimal for predicting the failure rate of each kind of water conduit. This model9s maximum relative error of predicting failure rates λ r and λ p during the testing stage amounted to about 4% and 14%, respectively. The average experimental failure rates in the whole analysed period amounted to 0.18, 0.44, 0.17 and 0.24 fail./(km·year) for the distribution pipes, the house connections and the distribution pipes made of respectively PVC and cast iron.
本文介绍了一种非参数回归方法——支持向量机(SVM)的故障率预测结果。超平面用于划分整个区域，使不同隶属关系的对象彼此分离。支持向量的个数决定了因变量和自变量之间关系的复杂程度。使用Statistical 12.0进行计算。2008-2014年期间供水系统的一个选定区域的运行数据(由水务公司提供)用于预测。2008-2014年的整个数据集(其中配电管道的数据与房屋连接的数据不同)被随机分为两个子集:训练子集- 75%(5年)和测试子集- 25%(2年)。因变量(分配管道λ r和住宅连接λ p)使用自变量(分配管道和住宅连接的总长度- L r和L p以及故障数量- N r和N p)进行预测。采用了四种核函数:线性基、多项式基、s型基和径向基。基于线性核函数的支持向量机模型对各类输水管道的故障率预测效果最优。该模型在试验阶段预测故障率λ r和λ p的最大相对误差分别约为4%和14%。在整个分析期内，配水管、房屋连接件和配水管的平均试验故障率分别为0.18、0.44、0.17和0.24次/(km·年)。
{"title":"Forecasting failure rate of water pipes","authors":"M. Kutyłowska","doi":"10.2166/WS.2018.078","DOIUrl":"https://doi.org/10.2166/WS.2018.078","url":null,"abstract":"This paper presents the results of failure rate prediction by means of support vector machines (SVM) – a non-parametric regression method. A hyperplane is used to divide the whole area in such a way that objects of different affiliation are separated from one another. The number of support vector determines the complexity of the relations between dependent and independent variables. The calculations were performed using Statistical 12.0. Operational data (provided by the Water Utility) for one selected zone of the water supply system for the period 2008–2014 were used for forecasting. The whole data set (in which data on distribution pipes were distinguished from those on house connections) for the years 2008–2014 was randomly divided into two subsets: a training subset – 75% (5 years) and a testing subset – 25% (2 years). Dependent variables ( λ r for the distribution pipes and λ p for the house connections) were forecasted using independent variables (the total length – L r and L p and number of failures – N r and N p of the distribution pipes and the house connections, respectively). Four kinds of kernel functions: linear, polynomial, sigmoidal and radial basis functions were applied. The SVM model based on the linear kernel function was found to be optimal for predicting the failure rate of each kind of water conduit. This model9s maximum relative error of predicting failure rates λ r and λ p during the testing stage amounted to about 4% and 14%, respectively. The average experimental failure rates in the whole analysed period amounted to 0.18, 0.44, 0.17 and 0.24 fail./(km·year) for the distribution pipes, the house connections and the distribution pipes made of respectively PVC and cast iron.","PeriodicalId":23573,"journal":{"name":"Water Science & Technology: Water Supply","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83710095","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
As the capital and a major political hub for China, Beijing has undergone a rapid urbanization effect with significant population growth in recent years. At the same time, Beijing has also been suffering from severe water problems such as, water scarcity, urban flooding and other issues related to water pollution. These have increasingly generated severe water problems and stymied the pace and scope of sustainable urban development. The critical challenges faced by water resource administrations pertains to the issues of sustainable management of water resources and the relevant actions to be put in place in order to address these water related problems. In this study, the current water situation of Beijing are described in great details focusing on the water resources amounts, water supply, water consumption and water pollution changes analyzed from historical to the recent years. The challenges of Beijing urban water management systems are also analyzed to offer possible solutions in light of the current trends. Finally, a number of useful strategies and action-oriented measures are provided for Beijing9s urban water resource administration to assist them in overcoming the current water management challenges and or them to move towards a more sustainable developmental city.
{"title":"Situations, challenges and strategies of urban water management in Beijing under rapid urbanization effect","authors":"Wen Liu, Weiping Chen, Q. Feng, R. Deo","doi":"10.2166/WS.2018.057","DOIUrl":"https://doi.org/10.2166/WS.2018.057","url":null,"abstract":"As the capital and a major political hub for China, Beijing has undergone a rapid urbanization effect with significant population growth in recent years. At the same time, Beijing has also been suffering from severe water problems such as, water scarcity, urban flooding and other issues related to water pollution. These have increasingly generated severe water problems and stymied the pace and scope of sustainable urban development. The critical challenges faced by water resource administrations pertains to the issues of sustainable management of water resources and the relevant actions to be put in place in order to address these water related problems. In this study, the current water situation of Beijing are described in great details focusing on the water resources amounts, water supply, water consumption and water pollution changes analyzed from historical to the recent years. The challenges of Beijing urban water management systems are also analyzed to offer possible solutions in light of the current trends. Finally, a number of useful strategies and action-oriented measures are provided for Beijing9s urban water resource administration to assist them in overcoming the current water management challenges and or them to move towards a more sustainable developmental city.","PeriodicalId":23573,"journal":{"name":"Water Science & Technology: Water Supply","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83339414","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Improved analysis and usage of water resources in the Taoer River basin requires an evaluation of the contributions of precipitation and human activities to runoff. In this study, we apply an integrated method combining the non-parametric Mann–Kendall trend test and the double-mass curve to analyze runoff data from 1961 to 2010. The major findings are as follows: (1) annual runoff showed a statistically significant decrease, while precipitation showed no significant trend; (2) an abrupt change point was identified in 1998 at four representative stations, resulting in the study period being divided into pre-change and post-change periods for subsequent analysis. The double-mass curves were approximately linear in the pre-change periods, indicating that the dominant factor was probably climate change. Annual precipitation–runoff curves showed a decreasing trend from 1998, probably because of human activity; (3) the contributions of human activity to runoff in the post-change period for the four selected stations were 58.31%, 17.81%, 37.17%, and 47.66%, and the influence of human activity increased after the abrupt change point.
{"title":"Quantitative impact of precipitation and human activity on runoff in the upper and middle Taoer River basin","authors":"Ying Sun, Xiujuan Liang, Changlai Xiao, Z. Fang","doi":"10.2166/WS.2018.049","DOIUrl":"https://doi.org/10.2166/WS.2018.049","url":null,"abstract":"Improved analysis and usage of water resources in the Taoer River basin requires an evaluation of the contributions of precipitation and human activities to runoff. In this study, we apply an integrated method combining the non-parametric Mann–Kendall trend test and the double-mass curve to analyze runoff data from 1961 to 2010. The major findings are as follows: (1) annual runoff showed a statistically significant decrease, while precipitation showed no significant trend; (2) an abrupt change point was identified in 1998 at four representative stations, resulting in the study period being divided into pre-change and post-change periods for subsequent analysis. The double-mass curves were approximately linear in the pre-change periods, indicating that the dominant factor was probably climate change. Annual precipitation–runoff curves showed a decreasing trend from 1998, probably because of human activity; (3) the contributions of human activity to runoff in the post-change period for the four selected stations were 58.31%, 17.81%, 37.17%, and 47.66%, and the influence of human activity increased after the abrupt change point.","PeriodicalId":23573,"journal":{"name":"Water Science & Technology: Water Supply","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89692195","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The main objective of this paper is to propose a method for quantifying the energy consumption in the life cycle of different plumbing fixtures. The method can be used to estimate the energy consumption in the production, use and disposal phases of plumbing fixtures. This allows for the comparison between the performances of different plumbing fixtures and the identification of the share of each phase on the energy consumption over the life cycle. The method was applied in a case study in Southern Brazil to quantify the energy consumption in the life cycle of two types of taps installed on a university campus. The total energy consumption in the life cycle of ordinary and self-closing taps used in the study was respectively, 177.71 MJ and 164.11 MJ over four years. Production accounted for 33% of the energy consumption share of the ordinary tap, while the use phase accounted for 65% and the disposal phase for 2%. For the self-closing tap, the production phase accounted for 46% of the energy consumption share, the use phase for 52% and the disposal phase for 2%. Therefore, considering the energy consumption in the life cycle, self-closing taps should be preferred over ordinary taps.
{"title":"Energy consumption in the life cycle of plumbing fixtures","authors":"A. Kalbusch, E. Ghisi","doi":"10.2166/WS.2018.053","DOIUrl":"https://doi.org/10.2166/WS.2018.053","url":null,"abstract":"The main objective of this paper is to propose a method for quantifying the energy consumption in the life cycle of different plumbing fixtures. The method can be used to estimate the energy consumption in the production, use and disposal phases of plumbing fixtures. This allows for the comparison between the performances of different plumbing fixtures and the identification of the share of each phase on the energy consumption over the life cycle. The method was applied in a case study in Southern Brazil to quantify the energy consumption in the life cycle of two types of taps installed on a university campus. The total energy consumption in the life cycle of ordinary and self-closing taps used in the study was respectively, 177.71 MJ and 164.11 MJ over four years. Production accounted for 33% of the energy consumption share of the ordinary tap, while the use phase accounted for 65% and the disposal phase for 2%. For the self-closing tap, the production phase accounted for 46% of the energy consumption share, the use phase for 52% and the disposal phase for 2%. Therefore, considering the energy consumption in the life cycle, self-closing taps should be preferred over ordinary taps.","PeriodicalId":23573,"journal":{"name":"Water Science & Technology: Water Supply","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81760806","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abdul Razzaq Khan, M. Rafique, S. Rahman, M. Basharat, Chand Shahzadi, Ishtiaq Ahmed
Radon activity concentration was measured in 101 springs and well water samples collected from Muzaffarabad city and its outskirts. Sixty springs and 41 well water samples were analyzed, using RAD7, an electronic radon detector manufactured by Durridge Company Inc., for the estimation of radon borne activities and their relevant effects. Results obtained show that for spring water, the water borne radon activity varied from 0.246 ± 0.348 to 34.36 ± 5.54 Bq L −1 with an average value of 10.16 ± 2.42 Bq L −1 . For well water, the water borne radon activity varied from 0.86 ± 0.10 to 16.12 ± 0.22 Bq L −1 with an average value of 4.21 ± 0.13 Bq L −1 . Concentration of radon borne activities were subsequently used for determination of inhalation and ingestion doses. The inhalation and ingestion doses for spring water samples varied from 0.0062 ± 0.0087 to 0.865 ± 0.14 mSv y −1 and 0.052± 0.073 to 7.22 ± 1.16 mSv y −1 , respectively. The inhalation and ingestion doses for well water varied from 0.022 ± 0.0025 to 0.41 ± 0.0054 mSv y −1 and 0.18± 0.021 to 3.38 ± 0.045 mSv y −1 , respectively. 33.33% of spring and 7.32% of well water samples were found with values above the recommendation levels of the United States Environmental Protection Agency (∼11.1 Bq L −1 ). As a single measurement cannot serve as a best estimate of the unsampled areas in the region, Kriging interpolation method, a geo-statistical method, was used to get an estimate of spatial distribution of water borne radon in the area of study. Kriging mapping shows that higher radon concentrations are found in areas with lithology consisting of sandstones, siltstones, shales and claystones.
在穆扎法拉巴德市及其郊区采集的101个泉水和井水样本中测量了氡活度浓度。采用美国Durridge公司生产的RAD7电子氡检测仪对60个泉水和41个井水样品进行了分析，以估计氡的携带活性及其相关影响。结果表明:泉水的氡活度变化范围为0.246±0.348 ~ 34.36±5.54 Bq L−1，平均值为10.16±2.42 Bq L−1;井水氡活度变化范围为0.86±0.10 ~ 16.12±0.22 Bq L−1，平均值为4.21±0.13 Bq L−1。氡传播活性的浓度随后被用于确定吸入和摄入剂量。泉水样品的吸入和摄入剂量分别为0.0062±0.0087 ~ 0.865±0.14 mSv y - 1和0.052±0.073 ~ 7.22±1.16 mSv y - 1。井水的吸入和摄入剂量分别为0.022±0.0025 ~ 0.41±0.0054 mSv y - 1和0.18±0.021 ~ 3.38±0.045 mSv y - 1。33.33%的泉水和7.32%的井水样本的值高于美国环境保护署的建议水平(~ 11.1 Bq L−1)。由于单次测量不能很好地估计研究区域内的未采样区域，因此采用地质统计学方法Kriging插值法对研究区域内水体氡的空间分布进行了估计。Kriging测图显示，在砂岩、粉砂岩、页岩和粘土岩岩性组成的地区，氡浓度较高。
{"title":"Geo-spatial analysis of radon in spring and well water using kriging interpolation method","authors":"Abdul Razzaq Khan, M. Rafique, S. Rahman, M. Basharat, Chand Shahzadi, Ishtiaq Ahmed","doi":"10.2166/WS.2018.070","DOIUrl":"https://doi.org/10.2166/WS.2018.070","url":null,"abstract":"Radon activity concentration was measured in 101 springs and well water samples collected from Muzaffarabad city and its outskirts. Sixty springs and 41 well water samples were analyzed, using RAD7, an electronic radon detector manufactured by Durridge Company Inc., for the estimation of radon borne activities and their relevant effects. Results obtained show that for spring water, the water borne radon activity varied from 0.246 ± 0.348 to 34.36 ± 5.54 Bq L −1 with an average value of 10.16 ± 2.42 Bq L −1 . For well water, the water borne radon activity varied from 0.86 ± 0.10 to 16.12 ± 0.22 Bq L −1 with an average value of 4.21 ± 0.13 Bq L −1 . Concentration of radon borne activities were subsequently used for determination of inhalation and ingestion doses. The inhalation and ingestion doses for spring water samples varied from 0.0062 ± 0.0087 to 0.865 ± 0.14 mSv y −1 and 0.052± 0.073 to 7.22 ± 1.16 mSv y −1 , respectively. The inhalation and ingestion doses for well water varied from 0.022 ± 0.0025 to 0.41 ± 0.0054 mSv y −1 and 0.18± 0.021 to 3.38 ± 0.045 mSv y −1 , respectively. 33.33% of spring and 7.32% of well water samples were found with values above the recommendation levels of the United States Environmental Protection Agency (∼11.1 Bq L −1 ). As a single measurement cannot serve as a best estimate of the unsampled areas in the region, Kriging interpolation method, a geo-statistical method, was used to get an estimate of spatial distribution of water borne radon in the area of study. Kriging mapping shows that higher radon concentrations are found in areas with lithology consisting of sandstones, siltstones, shales and claystones.","PeriodicalId":23573,"journal":{"name":"Water Science & Technology: Water Supply","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82040167","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The suspended sediment load estimation of rivers is one of the main issues in hydraulic engineering. Different traditional methods such as sediment rating curve (SRC) can be used to estimate the suspended sediment load of rivers. The main problem of this method is its low accuracy and uncertainty. In this study, the ability of three intelligence models namely Gene Expression Programming (GEP), Artificial Neural Networks (ANN) and Adaptive Neuro Fuzzy Inference System (ANFIS) were compared to the SRC method. The daily flow discharge and sediment discharge of two hydrometric stations of Kasilian and Telar rivers in the period of 1964–2014 were used to develop intelligence models. The performance of these methods indicated that all intelligence models give reliable results in the estimation of the suspended sediment load and their performance was better than the SRC method. Moreover, results showed that the GEP model with a high coefficient of determination (R 2 ) and a low mean absolute error (MAE) was better than both the ANN and ANFIS models for the estimation of daily suspended sediment load of the two sub-basins of Kasilian and Telar rivers.
{"title":"A comparison of artificial intelligence models for the estimation of daily suspended sediment load: a case study on the Telar and Kasilian rivers in Iran","authors":"S. Emamgholizadeh, Razieh Karimi Demneh","doi":"10.2166/WS.2018.062","DOIUrl":"https://doi.org/10.2166/WS.2018.062","url":null,"abstract":"The suspended sediment load estimation of rivers is one of the main issues in hydraulic engineering. Different traditional methods such as sediment rating curve (SRC) can be used to estimate the suspended sediment load of rivers. The main problem of this method is its low accuracy and uncertainty. In this study, the ability of three intelligence models namely Gene Expression Programming (GEP), Artificial Neural Networks (ANN) and Adaptive Neuro Fuzzy Inference System (ANFIS) were compared to the SRC method. The daily flow discharge and sediment discharge of two hydrometric stations of Kasilian and Telar rivers in the period of 1964–2014 were used to develop intelligence models. The performance of these methods indicated that all intelligence models give reliable results in the estimation of the suspended sediment load and their performance was better than the SRC method. Moreover, results showed that the GEP model with a high coefficient of determination (R 2 ) and a low mean absolute error (MAE) was better than both the ANN and ANFIS models for the estimation of daily suspended sediment load of the two sub-basins of Kasilian and Telar rivers.","PeriodicalId":23573,"journal":{"name":"Water Science & Technology: Water Supply","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73465270","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Garmendia, J. Almandoz, A. Arrizabalaga, F. Arregui
The benefits of applying pressure management in urban water supply networks have been well known for more than 10 years. Apart from reducing leakage, it also reduces burst frequency and consumption. However, the reduction of consumption with pressure is an objective that has only been considered a priority in water scarcity scenarios and suffers from a lack of systematic or conclusive studies. This paper analyses the relationship between pressure and consumption in a water distribution network equipped with remote water meter reading. Based on end use breakdowns, the paper estimates the percentage of pressure-dependent consumption. It establishes three different scenarios and assesses the relationship between pressure and consumption by means of the N3 coefficient.
{"title":"Pressure management and residential consumption reduction","authors":"M. Garmendia, J. Almandoz, A. Arrizabalaga, F. Arregui","doi":"10.2166/WS.2018.071","DOIUrl":"https://doi.org/10.2166/WS.2018.071","url":null,"abstract":"The benefits of applying pressure management in urban water supply networks have been well known for more than 10 years. Apart from reducing leakage, it also reduces burst frequency and consumption. However, the reduction of consumption with pressure is an objective that has only been considered a priority in water scarcity scenarios and suffers from a lack of systematic or conclusive studies. This paper analyses the relationship between pressure and consumption in a water distribution network equipped with remote water meter reading. Based on end use breakdowns, the paper estimates the percentage of pressure-dependent consumption. It establishes three different scenarios and assesses the relationship between pressure and consumption by means of the N3 coefficient.","PeriodicalId":23573,"journal":{"name":"Water Science & Technology: Water Supply","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87542688","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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