An air cushion chamber is a feasible and efficient hydraulic device to control water hammers for pressurized pipeline systems. Considering that all factors simultaneously can be incredibly difficult, even for a simple air chamber pipeline valve layout, this study introduces the dimensionless transfer function and expression for air chambers in the dimensionless frequency domain to effectively address the water hammer generation and its counteracting processes. To comprehensively characterize hydraulic transients for pipeline systems equipped with air chambers, two representative dimensionless parameters were used. One parameter corresponded to the main pipeline and the other to the air chamber. Along the pipeline system, it is possible to develop a frequency-independent expression for hydraulic impedance, which can be translated into a time-domain expression for pressure. A comparison between the developed method and other existing methods (e.g. characteristic method and impulse response method) revealed excellent agreement. Application of the dimensionless parameters to systems with different dimensions and hydraulic conditions shows that the proposed dimensionless parameters can address substantial ranges of real systems. It has been investigated how two dimensionless parameters have an impact on hydraulic responses over a wide range of parameter combinations and flow conditions.
{"title":"Generalized characterization of pipeline systems with air chamber through development of the dimensionless impedance response","authors":"Sanghyun Kim","doi":"10.2166/aqua.2024.129","DOIUrl":"https://doi.org/10.2166/aqua.2024.129","url":null,"abstract":"\u0000 \u0000 An air cushion chamber is a feasible and efficient hydraulic device to control water hammers for pressurized pipeline systems. Considering that all factors simultaneously can be incredibly difficult, even for a simple air chamber pipeline valve layout, this study introduces the dimensionless transfer function and expression for air chambers in the dimensionless frequency domain to effectively address the water hammer generation and its counteracting processes. To comprehensively characterize hydraulic transients for pipeline systems equipped with air chambers, two representative dimensionless parameters were used. One parameter corresponded to the main pipeline and the other to the air chamber. Along the pipeline system, it is possible to develop a frequency-independent expression for hydraulic impedance, which can be translated into a time-domain expression for pressure. A comparison between the developed method and other existing methods (e.g. characteristic method and impulse response method) revealed excellent agreement. Application of the dimensionless parameters to systems with different dimensions and hydraulic conditions shows that the proposed dimensionless parameters can address substantial ranges of real systems. It has been investigated how two dimensionless parameters have an impact on hydraulic responses over a wide range of parameter combinations and flow conditions.","PeriodicalId":513288,"journal":{"name":"AQUA — Water Infrastructure, Ecosystems and Society","volume":" 28","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141679098","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}
R. K. Pongiannan, R. Brindha, A. Geetha, K. Ganesan, M. JayeKumar, Telugu Maddileti, K. Preethivarshni
The demand for water resources has increased due to population growth and the effects of cyclical droughts on irrigated agriculture. Due to these current circumstances, there is an imbalance between the limited supply of water and the rising demand for water. According to this perspective, accurate data on the spatial and temporal patterns of stockholder water demand can only be obtained through effective water planning and management. Geographic information system (GIS) mapping and smart metering are being used to implement intelligent water supply systems for dependable water supply management. In water supply systems, GIS models aid in data comprehension, analysis, and querying using advanced technologies that can significantly enhance work in the field of urban planning. They can be utilised as analytical tools and significantly improve the skills of researchers and professionals who are tasked with looking into different water management options.
{"title":"Implementation of an intelligence drinking water supply system using GIS mapping and smart metering for reliable water supply management","authors":"R. K. Pongiannan, R. Brindha, A. Geetha, K. Ganesan, M. JayeKumar, Telugu Maddileti, K. Preethivarshni","doi":"10.2166/aqua.2024.179","DOIUrl":"https://doi.org/10.2166/aqua.2024.179","url":null,"abstract":"\u0000 \u0000 The demand for water resources has increased due to population growth and the effects of cyclical droughts on irrigated agriculture. Due to these current circumstances, there is an imbalance between the limited supply of water and the rising demand for water. According to this perspective, accurate data on the spatial and temporal patterns of stockholder water demand can only be obtained through effective water planning and management. Geographic information system (GIS) mapping and smart metering are being used to implement intelligent water supply systems for dependable water supply management. In water supply systems, GIS models aid in data comprehension, analysis, and querying using advanced technologies that can significantly enhance work in the field of urban planning. They can be utilised as analytical tools and significantly improve the skills of researchers and professionals who are tasked with looking into different water management options.","PeriodicalId":513288,"journal":{"name":"AQUA — Water Infrastructure, Ecosystems and Society","volume":"33 12","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141687538","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 discharge of fluoride-containing wastewater poses a severe threat to global water resources, ecosystems, and human health. Urgently needed are economically feasible and environmentally sustainable solutions for worldwide fluoride contamination. This study explores utilizing unmodified and modified red clay soils from China's Loess Plateau as adsorbents for fluoride mitigation. Sulfuric acid-modified red clay soil showed higher fluoride removal than unmodified, NaOH-modified, and thermally modified soils. Fluoride adsorption decreased with rising pH from 2.0 to 10.0 for unmodified (67.67–3.91%) and acid-modified red clay soil (90.44–32.06%). The Langmuir model better described the data (R2 = 0.9821, 0.9901 for unmodified, acid-modified soil), improving maximum adsorption capacity by 252%. Pseudo-second-order kinetics (R2 = 0.9925, 0.9954 for unmodified, acid-modified soil) accurately described the kinetic data. Acid modification improved reaction rates, shortening the breakpoint from 6.694 to 2.318 min1/2. Over time, the process transitioned from intraparticle diffusion to external mass transfer and intraparticle diffusion. FTIR analysis showed that acid modification strengthened ligand exchange and provided ion exchange opportunities. This study advances fluoride adsorption through innovative clay soil utilization, offering economical, viable, and environmentally friendly solutions.
{"title":"Enhanced fluoride removal from water using acid-modified red clay soil from the Loess Plateau of China","authors":"Bingzi Zhu, Runbin Duan, Yuzhen Li, Xinyu Lu, Yao Sun, Jiangqi Gao","doi":"10.2166/aqua.2024.045","DOIUrl":"https://doi.org/10.2166/aqua.2024.045","url":null,"abstract":"\u0000 \u0000 The discharge of fluoride-containing wastewater poses a severe threat to global water resources, ecosystems, and human health. Urgently needed are economically feasible and environmentally sustainable solutions for worldwide fluoride contamination. This study explores utilizing unmodified and modified red clay soils from China's Loess Plateau as adsorbents for fluoride mitigation. Sulfuric acid-modified red clay soil showed higher fluoride removal than unmodified, NaOH-modified, and thermally modified soils. Fluoride adsorption decreased with rising pH from 2.0 to 10.0 for unmodified (67.67–3.91%) and acid-modified red clay soil (90.44–32.06%). The Langmuir model better described the data (R2 = 0.9821, 0.9901 for unmodified, acid-modified soil), improving maximum adsorption capacity by 252%. Pseudo-second-order kinetics (R2 = 0.9925, 0.9954 for unmodified, acid-modified soil) accurately described the kinetic data. Acid modification improved reaction rates, shortening the breakpoint from 6.694 to 2.318 min1/2. Over time, the process transitioned from intraparticle diffusion to external mass transfer and intraparticle diffusion. FTIR analysis showed that acid modification strengthened ligand exchange and provided ion exchange opportunities. This study advances fluoride adsorption through innovative clay soil utilization, offering economical, viable, and environmentally friendly solutions.","PeriodicalId":513288,"journal":{"name":"AQUA — Water Infrastructure, Ecosystems and Society","volume":"5 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141693785","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}
J. L. Ng, Yuk Feng Huang, S. L. S. Yong, Jin Chai Lee, Ali Najah Ahmed, Majid Mirzaei
Climate change is intensifying the occurrence of extreme rainfall events, drawing attention to the importance of understanding the return period concept within the realm of extreme weather studies. This study evaluates the stationarity of extreme rainfall series on both monthly and annual series across East Malaysia, employing the Augmented Dickey–Fuller, Phillips Perron, and Kwiatkowski–Phillips–Schmidt–Shin tests. To model these extreme rainfall series, various probability distributions were applied, followed by goodness-of-fit tests to determine their adequacy. The study identified the stationary and non-stationary return values at 25-, 50-, and 100-year return periods. Additionally, maps depicting the spatial distribution for non-stationary increment were generated. The results indicated that extreme monthly rainfall exhibited stationary characteristics, while extreme yearly rainfall displayed non-stationary characteristics. Among the tested probability distributions, the generalised extreme value distribution was found to be superior in representing the characteristics of the extreme rainfall. Furthermore, a significant finding is that the non-stationary rainfall exhibits higher return values than those of stationary rainfall across all return periods. The northeast coast of Sabah highlighted as the most affected area, with notably high return values for extreme rainfall.
{"title":"Analysing the variability of non-stationary extreme rainfall events amidst climate change in East Malaysia","authors":"J. L. Ng, Yuk Feng Huang, S. L. S. Yong, Jin Chai Lee, Ali Najah Ahmed, Majid Mirzaei","doi":"10.2166/aqua.2024.132","DOIUrl":"https://doi.org/10.2166/aqua.2024.132","url":null,"abstract":"\u0000 Climate change is intensifying the occurrence of extreme rainfall events, drawing attention to the importance of understanding the return period concept within the realm of extreme weather studies. This study evaluates the stationarity of extreme rainfall series on both monthly and annual series across East Malaysia, employing the Augmented Dickey–Fuller, Phillips Perron, and Kwiatkowski–Phillips–Schmidt–Shin tests. To model these extreme rainfall series, various probability distributions were applied, followed by goodness-of-fit tests to determine their adequacy. The study identified the stationary and non-stationary return values at 25-, 50-, and 100-year return periods. Additionally, maps depicting the spatial distribution for non-stationary increment were generated. The results indicated that extreme monthly rainfall exhibited stationary characteristics, while extreme yearly rainfall displayed non-stationary characteristics. Among the tested probability distributions, the generalised extreme value distribution was found to be superior in representing the characteristics of the extreme rainfall. Furthermore, a significant finding is that the non-stationary rainfall exhibits higher return values than those of stationary rainfall across all return periods. The northeast coast of Sabah highlighted as the most affected area, with notably high return values for extreme rainfall.","PeriodicalId":513288,"journal":{"name":"AQUA — Water Infrastructure, Ecosystems and Society","volume":"2 2","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141693264","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}
Lin Shi, Jian Zhang, Xiao-dong Yu, Daoyong Fu, Wen-long Zhao
Hydraulic models of long-distance water supply systems are usually used to regulate valves and pumps to realize the expected water distribution. Establishing and calibrating the hydraulic model is time-consuming and requires many engineering parameters, which are usually uncertain. This paper proposes a metamodel based on artificial neural networks (ANNs) to replace the computationally costly hydraulic model. The metamodel is designed to bypass the modeling and calibration processes of the hydraulic model and directly estimate the target state of valves and pumps to realize real-time water distribution. The proposed approach uses the water levels of reservoirs and the flow demands of water plants as input data to the ANN. The metamodel's output prescribes the opening of regulating valves and the speed of pumps. A realistic case study is presented to validate the accuracy and efficiency of the approach. The results show that ANN is feasible as a state predictor to realize real-time water distribution in practical water supply projects.
长距离供水系统的水力模型通常用于调节阀门和水泵，以实现预期的水量分配。建立和校准水力模型非常耗时，而且需要许多工程参数，而这些参数通常是不确定的。本文提出了一种基于人工神经网络（ANN）的元模型，以取代计算成本高昂的水力模型。该元模型可绕过水力模型的建模和校准过程，直接估算阀门和水泵的目标状态，从而实现实时配水。所提出的方法将水库水位和水厂的流量需求作为 ANN 的输入数据。元模型的输出结果规定了调节阀的开度和水泵的转速。为验证该方法的准确性和效率，介绍了一个实际案例研究。结果表明，在实际供水项目中，ANN 作为状态预测器实现实时配水是可行的。
{"title":"Artificial neural network-based water distribution scheme in real-time in long-distance water supply systems","authors":"Lin Shi, Jian Zhang, Xiao-dong Yu, Daoyong Fu, Wen-long Zhao","doi":"10.2166/aqua.2024.087","DOIUrl":"https://doi.org/10.2166/aqua.2024.087","url":null,"abstract":"\u0000 \u0000 Hydraulic models of long-distance water supply systems are usually used to regulate valves and pumps to realize the expected water distribution. Establishing and calibrating the hydraulic model is time-consuming and requires many engineering parameters, which are usually uncertain. This paper proposes a metamodel based on artificial neural networks (ANNs) to replace the computationally costly hydraulic model. The metamodel is designed to bypass the modeling and calibration processes of the hydraulic model and directly estimate the target state of valves and pumps to realize real-time water distribution. The proposed approach uses the water levels of reservoirs and the flow demands of water plants as input data to the ANN. The metamodel's output prescribes the opening of regulating valves and the speed of pumps. A realistic case study is presented to validate the accuracy and efficiency of the approach. The results show that ANN is feasible as a state predictor to realize real-time water distribution in practical water supply projects.","PeriodicalId":513288,"journal":{"name":"AQUA — Water Infrastructure, Ecosystems and Society","volume":"6 15","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141700437","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 development of low-cost methods for wastewater treatment and the separation of oil-in-water emulsions is of considerable significance. Recently, natural material-based, inexpensive membranes have become a hot area of research. In this work, natural olive seeds were used to develop a novel ceramic membrane support. With the oil filtration process in place, the choice was reached to utilize the olive kernels’ beneficial qualities best. The process involved blending plastic paste with water and organic ingredients, followed by extruding the resulting paste into a porous tubular. After firing at 200 °C/2 h, the membrane's water permeability and porosity were 1,852 L/h m2 bar and 45%, respectively, and its average pore width varied from 2 to 15 μm. The efficiency of the microfiltration membrane in separating oil-in-water emulsions was assessed using two test solutions containing oil concentrations of 500 and 1,000 mg/L. Under a transmembrane pressure of 1 bar, the membrane exhibited exceptional permeate flux exceeding 200 L/m2 h, along with a high oil rejection rate of over 96% across all feed concentrations.
{"title":"A new ceramic microfiltration membrane based on olive seeds: development and characterization","authors":"Mourad Addich, Abdelillah Fatni, Siham Bouzrour, Gomathi Thandapani, Noureddine El Baraka, Abdellatif Laknifli","doi":"10.2166/aqua.2024.152","DOIUrl":"https://doi.org/10.2166/aqua.2024.152","url":null,"abstract":"\u0000 \u0000 The development of low-cost methods for wastewater treatment and the separation of oil-in-water emulsions is of considerable significance. Recently, natural material-based, inexpensive membranes have become a hot area of research. In this work, natural olive seeds were used to develop a novel ceramic membrane support. With the oil filtration process in place, the choice was reached to utilize the olive kernels’ beneficial qualities best. The process involved blending plastic paste with water and organic ingredients, followed by extruding the resulting paste into a porous tubular. After firing at 200 °C/2 h, the membrane's water permeability and porosity were 1,852 L/h m2 bar and 45%, respectively, and its average pore width varied from 2 to 15 μm. The efficiency of the microfiltration membrane in separating oil-in-water emulsions was assessed using two test solutions containing oil concentrations of 500 and 1,000 mg/L. Under a transmembrane pressure of 1 bar, the membrane exhibited exceptional permeate flux exceeding 200 L/m2 h, along with a high oil rejection rate of over 96% across all feed concentrations.","PeriodicalId":513288,"journal":{"name":"AQUA — Water Infrastructure, Ecosystems and Society","volume":"35 34","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141340344","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 study investigates rapid dynamic pressure variations in water distribution networks due to critical incidents such as pipe bursts and valve operations. We developed and implemented a machine learning (ML)-based methodology that surpasses traditional slow cycles of pressure data acquisition, facilitating the efficient capture of transient phenomena. Employing the Orion ML library, which features advanced algorithms including long short-term memory dynamic threshold, autoencoder with regression, and time-series anomaly detection using generative adversarial networks, we engineered a system that dynamically adjusts data acquisition frequencies to enhance the detection and analysis of anomalies indicative of system failures. The system's performance was extensively tested using a pilot-scale water distribution network across diverse operational conditions, yielding significant enhancements in detecting leaks, blockages, and other anomalies. The effectiveness of this approach was further confirmed in real-world settings, demonstrating its operational feasibility and potential for integration into existing water distribution infrastructures. By optimizing data acquisition based on learned data patterns and detected anomalies, our approach introduces a novel solution to the conventionally resource-intensive practice of high-frequency monitoring. This study underscores the critical role of advanced ML techniques in water network management and explores future possibilities for adaptive monitoring systems across various infrastructural applications.
本研究调查了配水管网中因管道爆裂和阀门操作等突发事件引起的快速动态压力变化。我们开发并实施了一种基于机器学习（ML）的方法，该方法超越了传统的缓慢压力数据采集周期，有助于有效捕捉瞬态现象。Orion ML 库采用了包括长短期记忆动态阈值、带回归的自动编码器和使用生成式对抗网络的时间序列异常检测在内的先进算法，我们设计的系统可动态调整数据采集频率，以加强对表明系统故障的异常情况的检测和分析。该系统的性能在不同运行条件下的试点规模配水管网中进行了广泛测试，在检测泄漏、堵塞和其他异常情况方面取得了显著提高。这种方法的有效性在实际环境中得到了进一步证实，证明了其操作可行性以及集成到现有配水基础设施中的潜力。通过根据学习到的数据模式和检测到的异常情况优化数据采集，我们的方法为传统的资源密集型高频监测实践引入了一种新的解决方案。这项研究强调了先进的 ML 技术在水网管理中的关键作用，并探索了自适应监测系统在各种基础设施应用中的未来可能性。
{"title":"Rapid response to pressure variations in water distribution networks through machine learning-enhanced data acquisition","authors":"Hyunjun Kim, K. Jung, S. Lee, E. Jeong","doi":"10.2166/aqua.2024.030","DOIUrl":"https://doi.org/10.2166/aqua.2024.030","url":null,"abstract":"\u0000 \u0000 This study investigates rapid dynamic pressure variations in water distribution networks due to critical incidents such as pipe bursts and valve operations. We developed and implemented a machine learning (ML)-based methodology that surpasses traditional slow cycles of pressure data acquisition, facilitating the efficient capture of transient phenomena. Employing the Orion ML library, which features advanced algorithms including long short-term memory dynamic threshold, autoencoder with regression, and time-series anomaly detection using generative adversarial networks, we engineered a system that dynamically adjusts data acquisition frequencies to enhance the detection and analysis of anomalies indicative of system failures. The system's performance was extensively tested using a pilot-scale water distribution network across diverse operational conditions, yielding significant enhancements in detecting leaks, blockages, and other anomalies. The effectiveness of this approach was further confirmed in real-world settings, demonstrating its operational feasibility and potential for integration into existing water distribution infrastructures. By optimizing data acquisition based on learned data patterns and detected anomalies, our approach introduces a novel solution to the conventionally resource-intensive practice of high-frequency monitoring. This study underscores the critical role of advanced ML techniques in water network management and explores future possibilities for adaptive monitoring systems across various infrastructural applications.","PeriodicalId":513288,"journal":{"name":"AQUA — Water Infrastructure, Ecosystems and Society","volume":"56 9","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141353393","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}
Each year, floods, as one of the natural calamities, lead to significant destruction in various regions globally. Consequently, precise flood prediction becomes crucial in mitigating human and financial losses and effectively managing water resources. To achieve this, Convolutional Neural Network and Long Short-Term Memory (LSTM) models were utilized in this study to map flood hazards in the Aji Chay watershed. Flood data points were collected from the study area and subsequently divided into two groups using the Absence Point Generation technique. The first group, comprising 70% of the data, served as the training dataset for model construction, while the remaining 30% formed the testing dataset for validation. Seven key factors influencing floods, namely, precipitation, land use, Normalized Difference Vegetation Index, drainage density, flow direction, topographic wetness index, and terrain ruggedness index, were identified through Leave-One-Feature-Out approach and employed in the modeling process. The LSTM model with a Kolmogorov–Smirnov (KS) statistic value of 88.14 was chosen as the best model based on the KS plot. The results revealed that approximately 37% of the study area fell into high and very high flood risk classes. These research findings can be valuable in the effective management of flood-prone areas and the reduction of flood damages.
{"title":"A novel approach to flood risk zonation: integrating deep learning models with APG in the Aji Chay catchment","authors":"Ali Abdollahzadeh Bina, Sina Fard Moradinia","doi":"10.2166/aqua.2024.023","DOIUrl":"https://doi.org/10.2166/aqua.2024.023","url":null,"abstract":"\u0000 \u0000 Each year, floods, as one of the natural calamities, lead to significant destruction in various regions globally. Consequently, precise flood prediction becomes crucial in mitigating human and financial losses and effectively managing water resources. To achieve this, Convolutional Neural Network and Long Short-Term Memory (LSTM) models were utilized in this study to map flood hazards in the Aji Chay watershed. Flood data points were collected from the study area and subsequently divided into two groups using the Absence Point Generation technique. The first group, comprising 70% of the data, served as the training dataset for model construction, while the remaining 30% formed the testing dataset for validation. Seven key factors influencing floods, namely, precipitation, land use, Normalized Difference Vegetation Index, drainage density, flow direction, topographic wetness index, and terrain ruggedness index, were identified through Leave-One-Feature-Out approach and employed in the modeling process. The LSTM model with a Kolmogorov–Smirnov (KS) statistic value of 88.14 was chosen as the best model based on the KS plot. The results revealed that approximately 37% of the study area fell into high and very high flood risk classes. These research findings can be valuable in the effective management of flood-prone areas and the reduction of flood damages.","PeriodicalId":513288,"journal":{"name":"AQUA — Water Infrastructure, Ecosystems and Society","volume":"68 2","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141353226","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}
Enrique Cabrera, José Manuel Abreu, E. Gómez, Roberto Del Teso, Elvira Estruch
In improving the energy efficiency of water transport systems, two critical stages are involved: assessment (to understand the system's operation and identify potential energy savings) and auditing (to locate and break down the energy losses). Both stages are based on energy balances, which can be conducted using either the extended Bernoulli equation or the energy integral equation. Both equations can be applied, but depending on the system, data availability, and the kind of study to be performed, one is preferable over the other. This paper analyses, applies and compares both equations, with a particular focus on the less commonly used energy integral equation in the hydraulic field. This more general equation includes thermal and transient effects and it is more suitable for analyzing complex systems. In contrast, the extended Bernoulli equation, while simpler to apply, can lead to the loss of relevant information, such as the evaluation of the topographic energy. The main objective of this work is to bridge the gap between these two fundamental energy equations and recommend the most appropriate one for hydraulic problems. Real examples are presented to show their differences and validate our recommendations.
{"title":"Assessing and auditing water transport systems by applying the energy equations","authors":"Enrique Cabrera, José Manuel Abreu, E. Gómez, Roberto Del Teso, Elvira Estruch","doi":"10.2166/aqua.2024.278","DOIUrl":"https://doi.org/10.2166/aqua.2024.278","url":null,"abstract":"\u0000 In improving the energy efficiency of water transport systems, two critical stages are involved: assessment (to understand the system's operation and identify potential energy savings) and auditing (to locate and break down the energy losses). Both stages are based on energy balances, which can be conducted using either the extended Bernoulli equation or the energy integral equation. Both equations can be applied, but depending on the system, data availability, and the kind of study to be performed, one is preferable over the other. This paper analyses, applies and compares both equations, with a particular focus on the less commonly used energy integral equation in the hydraulic field. This more general equation includes thermal and transient effects and it is more suitable for analyzing complex systems. In contrast, the extended Bernoulli equation, while simpler to apply, can lead to the loss of relevant information, such as the evaluation of the topographic energy. The main objective of this work is to bridge the gap between these two fundamental energy equations and recommend the most appropriate one for hydraulic problems. Real examples are presented to show their differences and validate our recommendations.","PeriodicalId":513288,"journal":{"name":"AQUA — Water Infrastructure, Ecosystems and Society","volume":"72 12","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141353217","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}
Bruna da Silveira Guimarães, Kepler Borges França, Danilo Freire de Sousa Santos, João Alexandre Rodrigues do Nascimento, Bernardo José Gomes de Matos da Costa e Silva
The cultivation of microalgae in domestic wastewater offers a sustainable solution for the treatment of effluents, while at the same time producing biomass rich in lipids, potentially usable in the production of biofuels. Furthermore, reuse contributes to the treatment of wastewater, transforming a byproduct into a valuable source of nutrients for the production of microalgae biomass. This study involves the production of microalgae in open cultivation, using domestic effluents as a source of nutrients in brackish environments, to study the potential for biodiesel production. Intracellular lipids were between 17 and 20%. As for the bioremediation capacity, the results showed removal levels greater than 95% of nutrients, as well as bacterial and pollutant load reduction. The growth kinetics and the prediction of theoretical kinetic models through the use of computational tools show significant differences, due to the lack of control of process parameters in open cultivations. Based on the literature review and market research, a cost analysis for large-scale production in open crops was made, comparing with closed crops and finding lower costs in the implementation, maintenance and production of biodiesel in the production open.
{"title":"Production of microalgae in wastewater and brackish waters: kinetic, lipid content, bioremediation and cost analysis studies","authors":"Bruna da Silveira Guimarães, Kepler Borges França, Danilo Freire de Sousa Santos, João Alexandre Rodrigues do Nascimento, Bernardo José Gomes de Matos da Costa e Silva","doi":"10.2166/aqua.2024.092","DOIUrl":"https://doi.org/10.2166/aqua.2024.092","url":null,"abstract":"\u0000 The cultivation of microalgae in domestic wastewater offers a sustainable solution for the treatment of effluents, while at the same time producing biomass rich in lipids, potentially usable in the production of biofuels. Furthermore, reuse contributes to the treatment of wastewater, transforming a byproduct into a valuable source of nutrients for the production of microalgae biomass. This study involves the production of microalgae in open cultivation, using domestic effluents as a source of nutrients in brackish environments, to study the potential for biodiesel production. Intracellular lipids were between 17 and 20%. As for the bioremediation capacity, the results showed removal levels greater than 95% of nutrients, as well as bacterial and pollutant load reduction. The growth kinetics and the prediction of theoretical kinetic models through the use of computational tools show significant differences, due to the lack of control of process parameters in open cultivations. Based on the literature review and market research, a cost analysis for large-scale production in open crops was made, comparing with closed crops and finding lower costs in the implementation, maintenance and production of biodiesel in the production open.","PeriodicalId":513288,"journal":{"name":"AQUA — Water Infrastructure, Ecosystems and Society","volume":"47 36","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141269872","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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