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There is a growing global interest in preserving transportation infrastructure. This necessitates routine evaluation and timely maintenance of road networks. The effectiveness of pavement management systems (PMSs) heavily relies on accurate pavement deterioration models. However, there are limited comparative studies on modeling approaches for rural roads in arid climatic conditions using the same datasets for training and testing. This study compares three approaches for developing a pavement condition index (PCI) model as a function of pavement age: classical regression, machine learning, and deep learning. The PCI is a pavement management index widely adopted by many road agencies. A dataset on pavement age and distress was collected over a twenty-year period to develop reliable predictive models. The results demonstrate that the regression model, machine learning model, and the deep learning model achieved a coefficient of determination ( R 2 ) of 0.973, 0.975, and 0.978, respectively. While these values are technically equal, the average bias for the deep learning model (1.14) was significantly lower than that of the other two models, signaling its superiority. Additionally, the trend predicted by the deep learning model showed more distinct phases of PCI deterioration with age than the machine learning model. The latter exhibited a wider range of PCI deterioration rates over time compared to the regression model. The deep learning model outperforms a recently developed regression model for a similar region. These findings highlight the potential of using deep learning to estimate pavement surface conditions accurately and its efficacy in capturing the PCI-age relationship. [ABSTRACT FROM AUTHOR]

Coupled human and natural systems (CHANS) represent dialectic interaction between human and nature subsystems. This dynamic interaction involves a prominent level of complexity stemming from the uncertain interrelation between the systems and the incorporated subsystems. The complexity within CHANS includes reciprocal effects, nonlinearity, uncertainties, and heterogeneity. Although many researchers have highlighted the significance of understanding the nature of the coupling effect, most of the prevailing literature emphasises either human or natural systems separately, while considering the other as exogenous, despite evaluating the reciprocal and complex interrelations. The current review utilises the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA). It focuses on synthesising the prevailing literature on the CHANS framework in several disciplines, focusing on the approach, findings, limitations, and implications. The review comprises 56 relevant articles, found through Endnote and Covidence database searches. The findings identify the dominant complexity character as reciprocal effects and feedback loops, confirming the complex interactions between human and natural systems. Furthermore, the review provides evidence surrounding the significance of developing an analytical framework that can better explain the complex connections between humans and nature, as it provides a comprehensive understanding of CHANS and their potential impacts. [ABSTRACT FROM AUTHOR]

Incorporating sustainability concepts at all decision-making stages in the construction of residential buildings is essential to maximize benefits without compromising functionality. This study aimed to identify and analyze the obstacles hindering the application of Agile Project Management (APM) in residential construction projects. The research specifically addressed the following questions: What are the key barriers to APM adoption in Nigerian residential construction projects? How do these barriers impact the effectiveness of APM in promoting sustainability? A questionnaire survey was distributed to 120 construction professionals in Nigeria, capturing insights on APM challenges. Exploratory factor analysis was employed to categorize these obstacles into four main areas: social, economic, human factors, and culture and expectations. Subsequently, partial least squares-structural equation modeling was used to construct a model assessing the significance of these barriers. The findings revealed that economic factors, with a statistical significance coefficient of 0.516, are the most significant barriers to APM adoption. Social factors, cultural expectations, and human factors also play notable roles, though to a lesser extent. The outcomes provide valuable guidance for decision-makers in Nigeria's construction sector, emphasizing the need for strategies that address economic constraints and foster greater adoption of APM practices to achieve cost reduction and enhanced sustainability. [ABSTRACT FROM AUTHOR]

Landfills are one of the main point sources of groundwater pollution. This research mainly aims to assess the risk of nitrate transport from the unlined landfill to subsurface layers and groundwater using experimental results and the SESOIL model. Samples from 12 groundwater wells downstream of the landfill were collected and analyzed in 2008, 21 years after the landfill construction. The average concentration in the wells was 54 mg/L, slightly higher than the World Health Organization ( 50 mg/L) standards. SESOIL model was used to predict the concentration at the bottom of the unsaturated zone. Results indicated that the current mean concentration at the bottom of the unsaturated zone is 75 mg/L. the model predicted that the level of NO3 will increased up to 325 mg/L within 30 years. Accordingly, the concentration in groundwater wells near the landfill area is expected to gradually increase with time. Although the current risk associated with the level might not be harm to adults, however, it might pose severe risks to both adults and infants in the near future due to leaching. Urgent mitigation measures such as final cell cover (cap), lining system and vertical expansion should be considered at the landfill to protect the public health in the area. [ABSTRACT FROM AUTHOR]

This study was conducted between 2008 and 2009 to investigate the impacts of treated wastewater irrigation on soil and alfalfa crop after 7 years of wastewater irrigation. Beit-Lahia Pilot Project (BLPP) was initiated in 2003 where alfalfa crop was irrigated with partially treated wastewater form Beit-Lahia wastewater treatment plant. A control unit irrigated with well water was initiated in parallel for comparison. Soil and alfalfa samples were collected and analyzed for the main physiochemical, fecal coliform (FC), and heavy metals level through the field trial and the applied wastewater quality was also tested. These results were compared with the available data from 2003 to 2007. Results revealed that there is a concern in using treated wastewater under current quality as it negatively impacted the soil physico-chemical properties. Sodium adsorption ratio and electrical conductivity increased significantly by about 160% and 130%, respectively, due to wastewater irrigation (WWI) in both soil layers compared with well water irrigation. WWI caused slight decrease in soil pH in both surface and subsurface soil layers while it increased the soil organic matter content which varied seasonally due to climatic conditions and alfalfa uptake. Slight metal built up was noticed due to wastewater irrigation while metals level remained in the allowable range for soil by the time of this study. Alfalfa metals uptake was within the permissible range. Occasional high FC (900 and 2100 CFU/ml) level was noticed in the applied wastewater did not cause soil biological contamination as the FC level in the soil at BLPP due to wastewater irrigation was almost 260 CFU/g. © 2014 American Institute of Chemical Engineers Environ Prog, 34: 648-654, 2015 [ABSTRACT FROM AUTHOR]

The evolving water scarcity in the Gaza Strip adds extra pressure on the limited available groundwater source and leads to water quality deterioration. There is a high need for sustainable nonconventional water resource. Wastewater reuse (WWR) is one of the main water strategies in the Gaza Strip due to the increase amount of generated wastewater and the rehabilitation of treatment facilities. However, WWR can generate negative impacts to the ecological and the socio- economical system once it has been poorly applied. The current study investigates the most sustainable WWR schemes by accounting for the impacts of WWR based on real field study. Multicriteria analysis and experts' judgment were used to identify the impacts of WWR and to prioritise the severity of these impacts, respectively. WWR impacts were weighed using multi criteria analysis DEFINITE software according to their relative importance. Results indicated that public health and cost of treatment are of the most concern. Spatial analysis using geographic information system (GIS 9.2) was conducted to investigate the areas with high potential for WWR over the Gaza Strip based on the multicriteria results. Resulted map showed that Gaza southern area has the high potential for WWR with the least possible generated impacts. [ABSTRACT FROM AUTHOR]

Microbial fuel cells (MFCs) are a viable source of clean and renewable energy from wastewater and gaining attention on a global scale. Thus, this research work focuses on the energy production from high-strength palm oil mill wastewater using MFCs. A state-of-the-art technique for improving the performance of MFCs by covering a carbon fibre anode with various sized powdered activated carbon (PAC) particles was investigated. In addition, the MFCs were tested at various hydraulic retention times (HRT) to assess the performance displayed by modified MFCs. Results showed that a relatively smaller amount of PAC with a diameter of 13 μm coated at the anode during the cultivation stage at a shorter hydraulic retention time (4 days) would produce 504.1 ± 8.7 mW m−3 of power, 39.9 ± 2.9% of chemical oxygen demand removal efficiency, and 299 ± 63 mL of biogas. While, MFC running at a longer hydraulic retention time (12 days) was able to produce more power and had better effluent quality than those operating at a shorter hydraulic retention period. [Display omitted] • Ability of MFC to produce energy and treat palm oil wastewater simultaneously. • MFC-carbon cloth anode coated PAC produced almost doubled energy than control. • About 10% higher COD removal with MFC-carbon cloth anode coated PAC than control. • Inverse relationship between biogas production and power generation was identified. [ABSTRACT FROM AUTHOR]