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Temporal and spatial water quality data are essential to evaluate human health risks. Understanding the interlinking variations between water quality and socio-economic development is the key for integrated pollution management. In this study, we applied several multivariate approaches, including trend analysis, cluster analysis, and principal component analysis, to a 15-year dataset of water quality monitoring (1999 to 2013) in the Thi Vai estuary, Southern Vietnam. We discovered a rapid improvement for most of the considered water quality parameters (e.g., DO, NH4, and BOD) by step trend analysis, after the pollution abatement in 2008. Nevertheless, the nitrate concentration increased significantly at the upper and middle parts and decreased at the lower part of the estuary. Principal component (PC) analysis indicates that nowadays the water quality of the Thi Vai is influenced by point and diffuse pollution. The first PC represents soil erosion and stormwater loads in the catchment (TSS, PO4, and Fetotal); the second PC (DO, NO2, and NO3) determines the influence of DO on nitrification and denitrification; and the third PC (pH and NH4) determines point source pollution and dilution by seawater. Therefore, this study demonstrated the need for stricter pollution abatement strategies to restore and to manage the water quality of the Thi Vai Estuary. [ABSTRACT FROM AUTHOR]

In remote communities, hybrid energy systems are increasingly used to improve the reliability and renewability of power supply. The techno-economic analysis is often used to develop these promising energy systems, ignoring some performance indicators and environmental factors. This study proposes a multi-approach framework for developing operationally feasible, economically viable, and environmentally sustainable hybrid energy systems in remote areas. A case study is conducted on Con Dao Island in Vietnam to supply its electricity demand using six on-grid and off-grid hybrid energy systems. After finding the best techno-economic configurations of the six developed systems, they are subjected to multi-approach analysis and exhaustive comparison using a set of performance, economic, and environmental indicators. An off-grid hybrid energy system comprising photovoltaics, wind turbines, lead-acid batteries, and diesel generators has the lowest net present cost (109.7 million USD) to supply the predicted island's electricity consumption (with a total on-site electricity generation of 184.1 GWh/yr). However, this off-grid system indicates the highest excess energy fraction (55%), while the on-grid systems with the ability to export excess energy to the grid have no excess energy fraction. In terms of eco-friendliness, an on-grid hybrid energy system consisting of a high level of photovoltaics and wind turbines shows the best results, with a negative total environmental impact and CO 2-eq emissions. This on-grid system shows the best cost of energy (0.1 USD/kWh) with approximately 450% less total environmental impact than the best off-grid system investigated, offsetting about 48.2 kilotonnes of CO 2-eq /yr by exporting net emission-free electricity. Overall, the proposed framework can assist decision-makers in finding feasible, viable, and sustainable hybrid energy systems. [Display omitted] • A multi-approach framework is used to develop hybrid energy systems for remote areas. • Six hybrid energy systems are developed to supply Con Dao Island's electricity demand. • An off-grid hybrid energy system has the lowest net present cost (109.7 million USD). • An on-grid hybrid system shows negative environmental impacts and CO 2-eq emissions. • The framework can help hybrid energy systems become feasible, viable, and sustainable. [ABSTRACT FROM AUTHOR]

Objectives: Workplace productivity has always been affected by a high-stress level and lack of sports activities. This aspect requires the researchers' emphasis and the present research performs this role by examining the much neglected impact of sports activities, stress management, and work-life balance on workplace productivity of manufacturing firms in Vietnam. The study also investigated the mediating impact of stress management and work-life balance among sports activities and workplace productivity of manufacturing firms in Vietnam. Methods: The primary data was collected through survey questionnaires from the employees of manufacturing companies in Vietnam. The research also applied the PLS-SEM using Smart-PLS to check the reliability and association among variables. Results: The outcomes indicated that sports activities, stress management, and work-life balance have a positive linkage with the workplace productivity of manufacturing firms in Vietnam. The outcomes also revealed that stress management and work-life balance significantly mediate among sports activities and workplace productivity of manufacturing firms in Vietnam. Conclusion: This research guides the policymakers in making policies related to workplace productivity improvement using sports activities, work-life balance, and stress management.