Shahmir Janjua

In the original publication [1], there were two mistakes in relation to the cited references (within the References section) as follows:Reference 52 (Xin-gang et al

This study examines the impact of upstream structures on the bulk drag coefficient of vegetation through experimental means, which has not been previously conducted. An embankment model was placed upstream of the vegetation, both with and without a moat/depression. The results showed that the presence of an upstream structure reduced the bulk drag coefficient of vegetation as the structure shared the drag. When only the embankment was placed upstream, a maximum decrease of 11% in the bulk drag coefficient was observed. However, when both the embankment and moat models were placed upstream, a 20% decrease in the bulk drag coefficient was observed. Regression models and artificial neural network (ANN) models were developed to predict the bulk drag coefficient based on the variables affecting it. Five ANN models with different training functions were compared to find the best possible training function, with performance indicators such as coefficient of determination (R²), root mean square error (RMSE), Nash–Sutcliffe efficiency (NSE), sum of square error (SSE), mean absolute error (MAE), and Taylor’s diagrams used to evaluate the model performance. The ANN model with nine neurons in each hidden layer performed the best, achieving the highest R² and NSE values and the lowest RMSE, SSE, and MAE values. Finally, the comparison between the regression model and the ANN model showed that the best ANN model outperformed the regression models, achieving R² values of 0.99 and 0.98 for the training and validation subsets, respectively.

Water scarcity is a major issue for developing countries due to the continuous increase in population every year, the major environmental challenges faced by developing countries such as Pakistan being the scarcity of water. One proposed solution to meet the requirements is to conserve water from rainfall. The process consists of the collection, storage, and use of rainwater. The rooftop rainwater harvesting systems (RWH) and rainfall harvesting system for artificially recharged water by recharge wells have received increased attention in the recent past as an efficient means of water conservation. In this study, both the systems have been analyzed for the University of Engineering and Technology Taxila (UET Taxila), Pakistan. The objective of this study is to propose a system to harvest water from the rooftops of all of the buildings on the campus and also to propose the most optimum locations of recharge wells for the artificial recharge of groundwater development. Numerous field visits were conducted after every rainfall over the past few months to identify lower elevation areas, which were further validated by the results obtained by Arc GIS. The total area of catchments available for rainwater harvesting in UET Taxila and the amount of water that could be harvested or used for replenishing groundwater reserves were also assessed in the current study. The results show that the harvestable rooftop water per month is 59% of the currently available source for watering trees and plants, and the harvestable water by recharge wells is 761,400 ft³ per year.

For the sustainable socio-economic growth, the energy supply is one of the foundations for any country. The gas shortage is one of the most significant impediments to any emerging country’s economic progress, making it a contested and disputed resource. In the middle of a supply–demand mismatch, distributing limited available gas across administrative units/provinces with competing requirements is a key challenge. In this work, an asymmetric gas allocation bargaining model is proposed under gas shortage to resolve natural gas-related disputes among Pakistan’s administrative units/provinces. Each administrative unit/province is characterized by its gas demand. Results show that the Nash bargaining theory, when applied under equal and bargaining weights, can address the supply–demand mismatches of the gas sector in Pakistan. Such an approach could help policymakers to make a fair gas-supply management system during gas shortage periods and would help in resolving the disputes between the provinces.