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• A comprehensive analysis of root causes for the accelerated internal corrosion in steel saltwater pipes coated with fusion bonded epoxy. • Cathodic delamination of the epoxy lining is identified as the primary cause of early internal corrosion failure. • Dynamic cyclic load has a greater chance for crack propagation in the epoxy lining compared to static load. • Development of recommendations and precautions based on the results of failure analysis. Effective functioning of saltwater supply system is essential to Hong Kong government agencies. However, it has been frequently observed that steel saltwater pipes suffered from severe internal corrosion and consequently early burst accidents, which may cause high economic loss and safety concerns to the public. Therefore, by taking a sample saltwater pipe made of DN450 mild steel with internal and external walls coated with fusion bonded epoxy in Hong Kong, this paper investigates the root causes and failure mechanism for the internal corrosion of this failed steel saltwater pipe through laboratory experiments and numerical simulation analysis. Two hypotheses are proposed and validated: (1) cathodic delamination of the epoxy lining, and (2) delamination of the epoxy lining due to external mechanical loads. The results verify that the sample saltwater pipe failed due to the cathodic delamination of the epoxy lining, and the electrochemical corrosion of the inner pipe wall. Moreover, it can be concluded that external mechanical load has few significant impacts on the damage of the epoxy lining for this sample pipe. This study exemplifies the importance of an in-depth analysis on the internal corrosion of steel water pipes, especially in a highly-corrosive internal environment. [ABSTRACT FROM AUTHOR]

Sewer overflow (SO) is becoming a concerning issue since discharged wastewater contains toxic substances and debris resulting in hazardous pollution to the surrounding environment and water quality degradation; and spilled stormwater may cause localized flooding and even back-up into buildings. Therefore, it is necessary to predict the occurrence of SO in advance, which enables the utilities to post warnings, prioritize the resource allocation and take proactive measures to minimize negative effects on environment and society. This paper aims to provide a state-of-the-art review for the prediction of sewer overflow which is lacking in literature, including bibliometric survey, scientometric analysis, in-depth systematic review, and elucidation of the existing research gaps and the potential future research directions. The findings reveal that the majority focuses on combined sewer overflow (CSO), and artificial intelligence-based models are the most popular ones. The input factors vary widely among three model categories. Volume , likelihood of occurrence and water level are the three mostly adopted output factors. Further research directions are recommended to fill these gaps (e.g., consider socio-economic factors and pipe properties, deploy IoT facilities to reduce false alarms, distinguish between regular and extreme weather conditions). This state-of-the-art review fills the gap of few endeavors focusing on SO prediction, and could provide the scholars and engineers with inclusive hindsight in dealing with harmful incidents. [ABSTRACT FROM AUTHOR]

• The incident records of gas transmission pipelines in the U.S. are investigated. • Effects of physical, environmental and operational factors are investigated. • The link between background, causal factors and incident consequences is explored. • Enhance a better understanding of pipeline failures and aid in development of predictive models. The contemporary world is confronted with a significant and pressing challenge in the form of the energy crisis. Natural gas represents a potential solution to the crisis, and its transportation relies heavily on transmission and distribution pipelines. Regrettably, these pipelines have witnessed a significant number of severe incidents in recent years due to various reasons. This study aims to investigate the influence of different background factors on pipeline incidents triggered by distinct causal factors, using incident records from the PHMSA in the United States. This study reveals that outside force damage is the most frequent causal factor, responsible for 41.21% of total incidents. The failure rate of gas transmission pipelines is notably affected by the operational pressure ratio and the laying location class. Moreover, this study explores the relationship between various factors and each causal factor leading to the incident, assessing the incident's consequences in terms of type, injury, fatality, and total cost. Generally, incidents involving larger-diameter pipelines with higher operational pressure ratios and deployed in higher location classes have more severe consequences, with the highest injury rate, fatality rate, and cost rate being 1.728 × 10−4, 1.043 × 10−4, and 1953.36 $ per incident per kilometer, respectively. These findings contribute to a better understanding of pipeline failures and can aid in the development of accurate and effective predictive models for gas pipelines. [ABSTRACT FROM AUTHOR]

Modular integrated construction (MiC) is a revolutionary construction method. However, the logistics management of MiC has always been a major barrier to the wider adoption of MiC. Nonetheless, this challenge can be tackled by the application of lean techniques, namely, just-in-time (JIT). Numerous studies have identified and evaluated the critical factors (CFs) required to implement JIT; however, there is no consensus among the previous studies on these CFs and their level of importance. Therefore, this research, for the first time, provides a systematic review and meta-analysis of these CFs. The systematic review identifies 42 CFs. To further provide a synthesis analysis of previous studies, a meta-analysis approach is used. This analysis is conducted on the identified CFs to evaluate their importance level and hence rank them. The results indicate that all the 42 CFs are important for applying JIT, of which seven are highly significant for successfully implementing JIT in MiC. Although the ranking obtained by meta-analysis is much more reliable than that provided in the individual studies, however, there is still a high heterogeneity in the results, which depicts the uncertain nature of the construction field. Therefore, sub-group analysis is conducted to investigate this heterogeneity and uncover the hidden patterns in the literature. This is achieved by studying the influence of predictive factors (moderators) on the importance level of CFs. This analysis shows that the economy of a country and the type of project executed are influential factors. The results further indicate that developing economies, in contrast to advanced economies, should pay more attention to three CFs. Also, the results show that seven CFs are much more important in MiC projects than the other project types. This research work is highly beneficial for theory development and for practitioners by identification of significant CFs that warrant management dedication to best apply JIT. Researchers, in particular, can consider the recommendations given here for implementing future meta-analysis studies. Image 1 • Critical factors to apply just-in-time in modular construction were reviewed. • Forty-two critical factors were identified through a systematic review. • The significance level of each critical factor was quantified through meta-analysis. • The study provided a more reliable evaluation and prioritization of these factors. • A sub-group analysis was conducted to study the effects of multiple moderators. [ABSTRACT FROM AUTHOR]

Modular integrated construction (MiC) has been an attractive research topic in the last decade. The adoption of this technology has increased in several countries worldwide, which shows the need for exploring its main research themes, characteristics, benefits, and challenges. Through a three-step research process integrating bibliometric search, quantitative analysis, and qualitative analysis, the literature of MiC was extensively analyzed. The aim was to identify ongoing research trends and current gaps that will benefit future research in this vital domain. The quantitative analysis of literature showed that almost 50% of research in MiC was conducted in only four countries. Science mapping of author keywords showed the connection between MiC and topics, such as simulation, sustainability, and scheduling, which indicated the diverse nature of the existing literature. The qualitative analysis of the literature showed that the categories of building design and management aspects were dominating the research in the area. Gaps in MiC research encompassed lack of quantitative analysis to assess the benefits of various innovative design proposals, lack of cost analysis for MiC to measure its savings, and lack of analysis to adopt the appropriate project delivery method in MiC projects. Future research directions comprise developing models to analyze stakeholder relationships during the design stage, examining contractual relationship among participants, investigating cost comparisons with different construction methods, and assessing the methods for introducing MiC into the curriculum of future engineers. This study provides a road map for future research projects and raise the practitioners' awareness of the latest methodologies and trends in global MiC research. • The study used mixed method analysis to review Modular integrated construction literature. • Journal and conference articles were analyzed. • Literature of MiC was categorized into six main categories and nine sub-categories. • Gaps in MiC literature were defined with analysis for current trends. • Future directions of research were provided. [ABSTRACT FROM AUTHOR]

Modular construction is considered as the future of the construction industry. While the sector is growing rapidly in some areas, there are still barriers to overcome. For more than two decades, several regions and countries, such as mainland China, Hong Kong, and Singapore, were using prefabricated/precast components to construct high-rise buildings in both private and public sectors. Such practices suffered from several limitations, which warrant the need for modular construction. Modular construction method needs to evolve so as to meet different regional requirements and restrictions, namely regulations, economy, market and building types. But the regional requirements and constraints on adopting modular construction remain unexplored. These differences are not widely appreciated. Hence, this research aims to perform comparative analysis of modular construction practices in terms of policies, specifications, and real projects in Hong Kong, Singapore, and mainland China. The results of the comparative analysis indicate that Singapore has developed a relatively effective policy system to help the construction industry embrace modular construction, while the three regions have not issued authoritative specifications. In general, modular construction still needs more support from the government, especially in terms of technical guidance and innovation. Cases studies show that the sustainability performance of modular construction is not balanced in terms of the economic, social and environmental dimensions. The lessons and challenges of modular construction drawn from the cases are also summarized. The construction industry should work closely with the government to achieve sustainable construction of modular building. The developed research on modular construction will increase the understanding of common practices in close countries where the industry in each can benefit from such practices to advance the domain. Image 1042 • This study aims to perform comparative analysis of modular construction practices. • The three regions have not issued authoritative specifications. • The sustainability performance of modular construction is not balanced. • Construction industry should work closely with the government in modular building. [ABSTRACT FROM AUTHOR]

Sewer overflow contains several hazardous contaminants causing adverse health effects and annoyance to the public. Despite this importance, few studies has hitherto been undertaken on examining the odor nuisance and risk of diseases due to contact with untreated overflow. However, quantitative investigation of odor emission from the sanitary sewage overflows has not been addressed. As such, this study aims to scrupulously investigate the deleterious impact of such phenomenon on public health in terms of the aforesaid matters. To this end, a multi-stage methodological approach was employed. Firstly, field data was collected from the vicinity of a wastewater treatment plant for three years, and then the concentrations of H 2 S in the aqueous phase and gaseous phase were estimated based on the environmental parameters. Afterward, the Gaussian aerial dispersion model and Quantitative Microbial Risk Assessment (QMRA) were employed. In parallel, the impact of the exposure to the malodorous H 2 S emitted from overflow cases was assessed. Furthermore, the results obtained from impact assessment were validated using the developed questionnaire survey. From the results obtained, the following major conclusions are drawn: (1) levels of H 2 S (g) near the overflow were high enough to be perceived by individuals, (2) concentrations of NH 3(g) in the ambient air were estimated lower than the perception threshold, (3) the sulfide concentration in the overflow was the most influential parameter with positive linear correlation with the concentration of H 2 S (g) , (4) the concentration of odor causes high annoyance, according to the questioning from the residents near the overflow events (5) exponential dose-response indicated 89–95% infection risk and (6) the good correlation between the estimated values of annoyance and the real annoyance level perceived by the residents proved accuracy of the methodology for estimation of H 2 S concentration and annoyance level. The unique findings obtained from this study guide the environmental decision-makers to take pre-emptive actions, preventing risk of infection and complaints from the residents. • A dispersion model is developed based on the wastewater and climate data. • A predictive-based model is developed to evaluate the annoyance of the odor from the sanitary overflows. • Initial sulfide concentration is the most significant parameter affecting the odor from an overflow. • The infection risk from the exposure to the sanitary overflows is assessed. [ABSTRACT FROM AUTHOR]

The deterioration of water pipes causes significant socio-economic and environmental burdens. Many predictors/factors are used to mitigate such problems by modelling the water pipe deterioration. However, these predictors have not been thoroughly investigated in the literature. This study adopts mixed systematic and scientometric analyses to review the predictors used in modelling water pipe deterioration. Within the study context, the predictors are categorised into pipe-related, soil and corrosion-induced, operational, and environmental. The results reveal that the pipe-related predictors have received the most attention in the reviewed studies, whereas further investigations are required to study long-term changes in the environmental-induced predictors. Accordingly, future research directions are recommended to fill these gaps (e.g., considering sustainability issues, and deploying real-time monitoring, and IoT facilities to enhance data availability. These directions greatly benefit practitioners and researchers from multidisciplinary backgrounds in research directions related to water pipes. [Display omitted] • The article reviews the predictors of the water pipe deterioration models. • A three-tier methodology is used to perform the review process. • Binary response statistic is used to extract the predictors and analysis them. • The fault tree diagram captures the logic behind the effect of the predictors on the water pipe deterioration. • Research gaps are discussed, and future direction are recommended. [ABSTRACT FROM AUTHOR]

The need for sustainable water infrastructure systems continues to grow as clean water is essential for daily life. Despite efforts to sustain water distribution networks (WDNs), they often experience frequent failures, leading to several environmental, social, and economic consequences. Previous studies have investigated the causes of water pipe failure in different contexts. However, a comprehensive and holistic understanding of these causes is lacking in the literature. Therefore, this study contributes to the existing knowledge by presenting 1) a scientometric analysis of the previous literature, 2) a systematic discussion of the causes, 3) an Analytical Hierarchy Process model and fault tree logic to prioritize and map the causes, respectively, and 4) an overview of techniques used in developing failure prediction models. The scientometric analysis reveals that little attention has been paid generally to the operational causes of water pipe failure. The same trend was supported by the systematic review, which divides a total of 33 causes into three main categories: pipe-related, environment-related, and operation-related causes. This study gives insights to academics and practitioners working in this domain on the contributions of various factors to the failure of water pipes, which would be useful in designing a sustainable and resilient WDN. [ABSTRACT FROM AUTHOR]

• Comprehensive scientometric and systematic reviews of corrosion protection methods for metallic pipelines are detailed. • 122 research articles are used to divide, classify, and discuss external and internal corrosion protection methods. • The functions, limitations, and requirements of corrosion protection methods are reported and discussed. • The purpose of this review is to assist researchers in filling research gaps and focusing on future directions. Metallic pipelines carrying water and/or oil/gas are exposed to deterioration, leaks/bursts, and failures due to corrosion. A suitable corrosion protection technique can prevent corrosion of these metallic pipelines, particularly in hostile environments, and corrosive soils. It can also reduce pipe deterioration, leaks/breaks, and failure, prolong service life, and improve the transportation process. Based on prior studies, this comprehensive review is regarded as an early attempt to cover both external and internal corrosion protection techniques for metallic pipelines in depth. The external corrosion protection techniques are classified into passive, active and hybrid corrosion protection techniques. The passive techniques include coatings, linings, barriers, material design, electrical isolation, inhibitors, and multi-passive techniques. Whereas active corrosion protection techniques include sacrificial anode and impressed current cathodic protections. Active and passive techniques are frequently combined to provide a more comprehensive corrosion protection system against newly discovered corrosion causes or coating degradations. On the other hand, internal corrosion protection techniques include internal coatings/linings/barriers, corrosion allowance, inhibitors/chemical treatments, dehydration, pigging, pipe material selection and flow control. The functions, merits, demerits, limitations/shortcomings, and requirements of corrosion protection techniques, as well as the various considerations that control their use have been covered and discussed. This comprehensive review will assist researchers, practitioners, and the industrial sector in prioritizing their policies in order not only to select the appropriate external and internal corrosion protection technique but also to fill current research gaps and focus on the future directions. [ABSTRACT FROM AUTHOR]

• Mechanical properties in centrifugal casting ductile iron pipes vary across thickness. • Equations are proposed to evaluate tube properties in ring hoop tension test. • Casting defects cause material inhomogeneity in ductile iron pipe walls. • Round bars in pipeline standards tend to overestimate actual pipe behaviour. Ductile iron pipes are widely used in pipe manufacturing for water and sewage transmission and distribution. In pipeline standards such as EN545, the pipe material is assumed isotropic and its mechanical properties are determined by tensile testing of round bars extracted along the longitudinal direction. This study experimentally examined the mechanical properties of centrifugal casting ductile iron pipes, focusing on the effects of sampling orientation, location, preparation, and test methodology. A ring hoop tension test (RHTT) was designed to evaluate circumferential properties. Force analysis of RHTT was performed and theoretical equation was derived to quantify the friction coefficient that existed between the coupon specimen and the loading fixture. A numerical study was conducted to further validate the effectiveness of the proposed theory. The test results indicated that the pipe mechanical property was inhomogeneous across the wall thickness, being inferior in the internal section and superior in the middle and external sections. This inferior layer would develop crack first and lead to subsequent outward propagation. This phenomenon led to a substantial degradation in the overall mechanical performance of the entire specimens, in comparison to the material in the middle portion. The material exhibited better performance in the circumferential direction compared to the longitudinal direction in terms of its mechanical properties, such as tensile strength and ductility. Flattened specimens showed enhanced strength and reduced ductility compared to the base pipe material. Fractographic and metallographic analyses revealed the existence of casting defects of porosity and agglomerated graphite in the internal section, which were the primary cause of material inhomogeneity. The round bars suggested per EN545 tended to overestimate the actual mechanical behaviour of ductile iron pipes, and may not be a true representation of the finished product of pipes. Flattened specimens as per ASTM E8/E8M were not recommended for ductile iron pipe material assessment, as the flattening process altered the stress–strain characteristics significantly. [ABSTRACT FROM AUTHOR]

• Optimization of fleet size combination in containers terminal is presented. • The optimization minimizes both vessel turnaround time and handling cost. • A new double-cycling handling strategy is incorporated in the optimization process. • The new strategy saved 20% in both time and cost and increased productivity by 25% Every few years, larger containerized vessels are introduced to the market to accommodate the increase in global trade. Although increasing the capacity of vessels results in maximizing the amount of imported and exported goods per voyage, yet it is accompanied with new challenges to terminal planners. One of the primary challenges is minimizing the vessel turnaround time with the least possible cost. In this context, this paper presents the development of a multi-level optimization model using the elitist non-dominated sorting genetic algorithm (NSGA-II) to determine the optimal or near-optimal fleet size combination of the different container handling equipment used in the terminal. The model aims to minimize two conflicting objective functions, namely, vessel turnaround time and total handling cost. Furthermore, the model considers a double-cycling strategy for the container handling process to achieve increased productivity and eventually more reduction in the vessel turnaround time. The model was implemented on a real-life case study to demonstrate its efficiency and the benefit of employing the double-cycling strategy compared with the traditional single-cycling strategy. The results demonstrated the efficiency of employing the double-cycling strategy by providing a reduction of above 20% in both the vessel turnaround time and the total handling cost and an increase of above 25% in the productivity when compared to the traditional single-cycling strategy. [ABSTRACT FROM AUTHOR]

• A four-point bending technique for measuring interface fracture toughness between a soft thin-film and a stiff substrate is developed. • The applicability of the technique is verified numerically. • The requirement for the specimen dimensions is proposed. • The technique is successfully applied to characterize the interface fracture toughness between a soft epoxy coating on a steel substrate. Interface fracture toughness, also called work of adhesion or adhesion energy, is a quantity characterizing the resistance of an interface between two adhered solids against interfacial delamination. Determining the interface fracture toughness should be of great value to the studies on the related adhesion and delamination problems. Four-point bending test is an experimental approach that was originally used to measure the flexural stiffness and fracture toughness of monolithic materials. It was also used to characterize the fracture toughness of the interface when a bi-layered notched composite beam specimen is adopted (Int. J. Frac. 1989; 40: 235). However, this method does not work very well when a thin and soft material is encountered because the interface delamination cannot be triggered easily. To address this problem, in this paper, we revise the configuration of the four-point bending specimen from bi-layer to tri-layer by imposing an additional stiffer layer on the top of the thin and soft layer. The analytical solution to the energy release rate of the preexisting interfacial crack is revisited. Finite element analysis is carried out to assess the applicability and limitations of the analytical solution. With the modified four-point bending specimen, the interface fracture toughness between an epoxy coating and a steel substrate is successfully measured from the critical load that leads to the delamination of the preexisting interfacial crack. [ABSTRACT FROM AUTHOR]

Leakages from water pipelines cause economic losses and environmental hazards. Despite the damages, it is challenging to avoid leaks throughout the lifetime. However, leak detection and localization, especially in real-time, minimize the damage. Owing to the recent advances, the micro-electromechanical systems (MEMS) based technologies have started to gaining recognition for water network monitoring in real-time, however, a systematic literature review to analyze the existing research trends, technological advances, and future research opportunities are largely missing. This study has based its investigation on three main MEMS-based technologies for real-time monitoring: MEMS sensors wireless networks, MEMS accelerometers, and MEMS hydrophones. Firstly, a scientometric analysis is conducted to 1) retrieve relevant research articles through Scopus, Web of Science, and Google Scholar, 2) visualize the publication trends, and 3) analyze the science mapping of influential authors, countries, organization, and top keywords occurrences. Secondly, qualitative discussions are made on research themes and sub-themes within three technologies: 1) MEMS WSNs are classified into static and mobile sensor-based wireless sensor networks. Seven sub-themes are categorized under static sensor-based wireless sensor networks such as PIPETECT, whereas three sub-themes are categorized under mobile sensor-based WSNs such as TriopusNet; 2) MEMS accelerometers are categorized into accelerometers based machine learning models and wireless systems; and 3) MEMS hydrophones are represented under one category. Thirdly, nine research opportunities including automated models, on-field real network-based experimental studies, optimal placement of sensor nodes for energy savings in wireless sensor networks, and a comparative analysis of real-time technologies are revealed. This study enhances the familiarity of early researchers with the application of MEMS-based technologies for leak detection and localization and provides seasoned researchers with a platform for future research development. • MEMS-based technologies create opportunities to enhance real-time leak detection and localization in water supply networks. • MEMS-based wireless sensor networks, accelerometers, and hydrophones are classified into different themes and sub-themes. • The bibliometric search process, scientometric analysis, and qualitative analyses are discussed in detail. • Future research directions are provided. [ABSTRACT FROM AUTHOR]

A large portion of natural gas is transferred through transmission pipelines. For these facilities, in the United States, external corrosion has led to more than 1700 failures in the past decades, causing a property damage of approximately $189 M. Such numbers highlight the importance of maintaining such facilities in safe conditions to postpone corrosion failure. Given such criticality, addressing pipeline availability is of high importance from economic consequences perspective for a national economy. However, most of the developed methods merely rely on considering costs, reliability or condition levels as maintenance decision criteria and ignore the importance of continuity of operation and pipeline availability. In this research, a maintenance planning framework is proposed for external corrosion of gas transmission pipelines through an availability-centered reliability-based maintenance planning procedure. This framework is based on the pipeline reliability profile obtained from a Monte Carlo simulation. This simulation is carried on a previously developed failure prediction model for gas transmission pipelines buried in the Great Plains region of the U.S. and considers failure uncertainties. In addition, a discrete event simulation (DES) approach is proposed to assess an availability-cost indicator of different maintenance scheduling alternatives for the case study of a 24-inch gas pipeline. This research reveals that a combination of wrap and replacement maintenance actions at the service life of 30.1 and 40.5 years respectively, is the most effective maintenance alternative in terms of improvement of availability per unit cost for the presented case study. This framework can help pipeline professionals in maintaining such facilities by considering their criticality using an availability-based maintenance scheduling approach. Such method can complement the conventional cost-based industry practices. • If added to inspections, maintenance planning models help avoid excessive inspections. • As a critical asset, considering gas pipeline availability helps reduce shutdowns. • As decision criteria, availability change per cost provides a balance between the two. • Combination of composite wrap with replacement is identified as the most effective. [ABSTRACT FROM AUTHOR]

Ranking and prioritizing pavement infrastructure for maintenance and rehabilitation have become major undertakings for several departments of transportation around the globe. This is a complex decision-making problem because multiple and conflicting criteria can contribute to the assessment. Multi-criteria decision analysis (MCDA) techniques evaluate the trade-off between several quantitative and qualitative criteria and facilitate complex decision-making. This research introduces a framework based on MCDA to support pavement management decision making, while quantifying emerging sustainability-related factors such as safety, noise, and pollution in the decision-making process. The framework features include 1) identifying pavement management main decision elements: objectives, criteria, and attributes by detailing the problem with a five-level hierarchy structure; 2) employing combined analytic hierarchy process and multi-attribute utility theory to develop representative set of utility functions; and 3) ranking and prioritizing large networks of pavement sections while incorporating sustainability-related criteria. Data used to assess the decision criteria and develop the utility functions is extracted by means of a questionnaire survey completed by professionals working in the field of pavement management. The proposed method is applied to a case study consisting of ten pavement sections extracted from the long-term pavement performance database, wherein the sections are ranked based on their attributes. Sensitivity analysis is performed to evaluate the impact of the different criteria on the ranking process. The proposed method has shown potential in ranking pavement networks based on the identified criteria. Future work can test the performance of the proposed methodology with a full-scale pavement network and apply it to other civil infrastructure assets to evaluate its performance with different types of projects. • Pavement management decision elements (objectives, criteria and attributes) are analyzed. • Integrated AHP-MAUT decision support framework for pavement management is developed. • An intuitive procedure to assess utility is implemented to develop the needed utility functions. • Data extracted from LTPP database is used to demonstrate the application of the proposed framework. • Sensitivity analysis is conducted to assess robustness of the developed method. [ABSTRACT FROM AUTHOR]

Estimating wastewater treatment plants' (WWTPs) influent parameters such as 5-day biological oxygen demand (BOD 5) and chemical oxygen demand (COD) is vital for optimizing electricity and energy consumption. Against this backdrop, the existing body of knowledge is bereft of a study employing Artificial Intelligence-based techniques for the prediction of BOD 5 and COD. Thus, in this study, Gene expression programming (GEP), multilayer perception neural networks, multi-linear regression, k-nearest neighbors, gradient boosting, and regression trees -based models were trained for predicting BOD 5 and COD, using monthly data collected from the inflow of 7 WWTPs over a three-year period in Hong Kong. Based on different statistical parameters, GEP provides more accurate estimations, with R2 values of 0.784 and 0.861 for BOD 5 and COD respectively. Furthermore, results of sensitivity analysis undertaken by monte Carlo simulation revealed that both BOD 5 and COD were mostly affected by concentrations of total suspended solids, and a 10% increase in the value of TSS resulted in a 7.94% and 7.92% increase in the values of BOD 5 and COD, respectively. It is seen that the GEP modeling results complied with the fundamental chemistry of the wastewater quality parameters and can be further applied on other sewage sources such as industrial sewage and leachate. The promising results obtained pave the way for forecasting the operational parameters during sludge processing, leading to an extensive energy savings during the wastewater treatment processes. • Different machine learning techniques for predicting BOD 5 and COD were employed. • GEP showed superior performance against other machine learning-based techniques. • BOD 5 and COD were correlated with TSS, NH 3 , OrgN, InorgP and OrgP. • The sensitivity analysis was undertaken through Monte Carlo simulation. [ABSTRACT FROM AUTHOR]

Developing a sustainable community is mainly contingent upon energy infrastructure driven by energy alternatives. It has been attempted to accomplish energy sustainability by just ranking energy alternatives. In the current work, an integrated decision support tool (IDST) and multi-level hierarchical structure (MLHS) are developed to instigate new notions for energy alternatives. The developed IDST is unique in dealing with two-dimensional assessment information and can also concurrently analyze hybrid information. The MLHS comprises eighteen attributes grouped into five sustainability aspects (operational, economic, technological, environmental, and social) to assess energy alternatives, including gas, coal, nuclear, solar, hydro, wind, and biomass. Firstly, the importance of attributes is calculated using the optimal weighting approach. Then, the ranking of alternatives is determined and validated. Lastly, the multi-facet performance of alternatives is assessed in terms of distributed performance and indexing using the probabilistic evidential reasoning algorithm, and the acceptability of alternatives is classified. The results revealed hydro is the most favorable energy alternative for achieving sustainability, followed by solar and wind, with a 'very good' index overall. The developed framework is useful for designing sustainable hybrid energy infrastructures and for intergovernmental organizations to draft long- and short-term policies for achieving the energy sustainability targets of SDG-7. • Constructed critical success factors for energy system quantitatively. • Evidential reasoning driven integrated multi-attribute decision tool is used. • Two-dimensional and hybrid assessment information of factors is used concurrently. • Sustainability is evaluated using some new notions in energy domain. • Long- and short-term policy recommendations for energy sustainability in Pakistan. [ABSTRACT FROM AUTHOR]

• Critical causes of RMAA-related accidents are identified. • Novel hybrid fuzzy-based algorithms are employed for result accuracy enhancement. • Considerable inherent interrelationships exist among RMAA-related causal factors. • "Limited financial/safety resources of SMEs" is the most influential causal factor. • The identified causes are prioritized using IVIF-DEMATEL-ANP method. Despite the recent improvements made to the area of occupational health and safety (OHS) within the construction sector, the Repair, Maintenance, Minor alteration, and Addition (RMAA) works have been given scant attention. In this study, given the significance of the injuries reported in the RMAA sector, a meticulous investigation is conducted into the causal factors contributing to the related accidents by capturing their causal interrelationships together with their importance levels. To this end, first, a comprehensive list of factors contributing to RMAA accidents was obtained through an extensive literature review and experts' interviews. Then, through the lenses of qualified relevant experts in Hong Kong, the proposed interval-valued intuitionistic fuzzy (IVIF) DEMATEL and IVIF analytic network process were employed to respectively uncover the cause-and-effect relationships among these factors and prioritize them. The findings show that "the lack of assessment and praising of workers' OHS understanding and performance," "the high turnover rate of workers resulting in difficulties in providing safety training and education," and "lack of safety training for workers" are the most critical causes to be given full attention by construction safety managers. The methodological approach proposed in this study brings about two theoretical contributions: unraveling interrelationships existing among the causal factors, and prioritization of them considering their interrelationships. The findings reported in this study also aid decision-makers in improving the critical causal factors in a way to enhance the OHS of RMAA sector. [ABSTRACT FROM AUTHOR]

One of the main components of smart and sustainable urban management is well-performed sewer networks. Therefore, maintaining and enhancing the functionality of sewer projects at an affordable cost are major challenges for decision-makers. However, the embracement of the Value Engineering (VE) concept to assess new sewer designs has not yet been fully embraced especially in developing countries. Thus, this study introduces a systematic VE approach for major sewer projects. A computer model based on six phases of VE methodology was developed, and named "Value Engineering Model" (VEM). To show its efficacy, it was applied to a real-life case study, leading to the following major contributions to the body of relevant knowledge: (1) unraveling the logical relations between the project functions, (2) a detailed life cycle cost analysis (LCCA), (3) a weighted evaluation matrix towards facilitating the decision-making procedure and (4) achieving an approximate 36% reduction in the sewer's project cost as compared to the common VE analysis technique. The developed model serves as a guide for design engineers and decision-makers in sewer projects. It will enable achieving the embracement of smart and sustainable drainage systems within cities at a greater pace. The results of this study will be a guide for decision-makers to reduce costs and improve sustainability by introducing VEs in the Egyptian sewer industry. • A new inclusive value engineering model for major sewer projects is developed. • The logical relations between the project functions are unravelled. • A detailed life cycle cost analysis (LCCA) of sewer projects is provided. • A weighted evaluation matrix towards facilitating the decision-making procedure is developed. • An approximate 36% reduction in the sewer's project cost is achieved. [ABSTRACT FROM AUTHOR]

The present study proposes a novel hybrid methodological approach for meticulously investigating the factors causing Sewer Overflow (SO). The proposed framework is based on a systematic literature review, experts' interviews, PLS-SEM statistical technique, and system dynamic modeling. Based on a large number of data collected from experts having rich experience in developed countries, three major findings are obtained: (1) three main factors and eighteen sub-factors are the main culprit of SO occurrence, (2) under design pipe diameter, blockages, and infiltration and inflow are the most significant sub-factors within the respective clusters, and (3) physical-related sub-factors are the most influential causes of SO occurrence under a dynamic environment. The findings attained in this study offer an insightful account for the concerned environmental decision-makers on coming up with further fecund measures towards reducing the magnitude of SO, preserving our environment from the occurrence of such harmful incidents. [Display omitted] • Through extensive literature review and experts' interviews, the contributors to sewer overflow are identified. • Through the PLS-SEM, the significance of identified contributors is quantified. • Using the System Dynamic Modeling, complex interrelationships among the contributors are uncovered. • Several theoretical and managerial implications are offered for the concerned decision-makers. [ABSTRACT FROM AUTHOR]