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This paper explains the evolving role of the local supply chain across different disruption scenarios. A systematic literature review of 91 papers from 33 journals supports definition of the local supply chain and explication of benefits before, during and after COVID-19 disruption. Resilience emerges as the prevalent benefit at each stage, but to varying scales. In the pre-COVID-19 era, where the local supply chain serves as a back-up approach to the more dominant global supply chain, localisation's capacity to absorb change promotes resilience to mitigate low-magnitude disruption. At initial outbreak of COVID-19 disruption the local supply chain was necessitated as an emergency response to the untenability of global operations, demonstrating transformational resilience to survive. As disruption continued, the local supply chain upscaled and adapted to recover. In the post-COVID-19 era, resilience is expected to remain a strategic priority, promoting continued investment in local operations to thrive with embedded resilience. As a result, the COVID-19 pandemic welcomed a point of transition for the local supply chain as capacities and benefits are revaluated and localisation recognised as critical in developing resilient supply networks for the future. This study consolidates this evolution to offer a propositional framework showcasing the local supply chain across different disruption scenarios. This offers long overdue definition and explanation of the local supply chain and its relationship with resilience, addressing an existing lack of academic attention and encouraging alignment of local-versus-global decisions with changing strategic priorities. [ABSTRACT FROM AUTHOR]

COVID–19 has disrupted human life considerably since the beginning of 2020. The transport sector is one of the most affected sector due to restrictions imposed to curb COVID–19 pandemic. This paper evaluates the environmental impacts of COVID–19 response scenarios using life cycle assessment approach. Six regions selected for the study are Australia, China, European Union (EU), India, United Kingdom (UK), and United States of America (USA). Data for vehicle population, vehicle kilometers travelled, fleet type, and fuel efficiency were used for 2015–2020. The environmental impacts were calculated for five scenarios; Baseline–2019, Business As Usual (BAU) and COVID–19 Response Scenario (CRS) for 2020 and 2030 namely, 2020–BAU, 2020–CRS, 2030–BAU, and 2030–CRS. The results indicate that COVID–19 occurrence and related response measures did not contribute to significant environment benefits in terms of Global Warming Potential (GWP) and other pollutants in short term and long term. This implies that although immediate reductions in emissions were observed in many studies, the long term effects were minimal due to irregular policies and unmanaged demand. Further, to achieve environment benefits sustained measures should be implemented in long term with proper planning and supporting infrastructure. Although electric vehicle strategies will provide benefits; emphasis on vehicle production and fuel production technologies is also needed to achieve the emission reduction targets. The findings are relevant for policy makers while devising policies to achieve the targets. • Vehicle stock will grow significantly in 2030 for developing countries • China's 2030 transport sector GWP will be highest, 1772 MT CO 2 eq, surpassing USA • Only USA showed reductions for all pollutants in 2030 COVID-19 response scenario • All countries had similar trends for most pollutants at different life cycle stages • COVID–19 occurrence didn't contribute to significant benefits in short & long term [ABSTRACT FROM AUTHOR]

Since the beginning of the COVID-19 outbreak, understanding its impacts on cities has received much attention in science and policy circles. This paper systematically reviews the literature on the interface of the pandemic and urban sustainability. The objective is to portray the impacts brought by the COVID-19 outbreak in urban environments within the sustainability framework and to detect trends and challenges for future research. The paper follows a methodology that integrates both bibliometric and systematic review approaches. The first approach relies on bibliometric analysis to provide an overview of the landscape of main trends on this nexus. The second approach presents a content analysis that deepens the work by outlining the impacts of the pandemic and the challenges that emerged on five different key topics for urban sustainability. The role of resilient urban planning is discussed as an integrative concept to face diverse challenges in the construction of sustainable cities in a post-pandemic scenario. Likewise, the study deliberates on future research topics related to resilient urban planning, social equity, healthy urban environments, sustainable mobility, and circular economy. This review serves as a guide for researchers and urban planners to understand emerging challenges and future research trends in urban sustainability. [Display omitted] • A literature review integrating bibliometric and contents analysis synthesizes the effects of the COVID-19 on the urban sustainability. • The impacts are sorted into thematic areas: resilient urban planning, healthy urban environments, social equity, sustainable mobility, and circular economy. • Challenges for urban sustainability and resilience are proposed as topics for future research work. [ABSTRACT FROM AUTHOR]

The COVID-19 has become a global pandemic that dramatically impacted human lives and economic activities. Due to the high risk of getting affected in high-density population areas and the implementation of national emergency measures under the COVID-19 pandemic, both travel and transportation among cities become difficult for engineers and equipment. Consequently, the costly physical commissioning of a new manufacturing system is greatly hindered. As an emerging technology, digital twins can achieve semi-physical simulation to avoid the vast cost of physical commissioning of the manufacturing system. Therefore, this paper proposes a digital twins-based remote semi-physical commissioning (DT-RSPC) approach for open architecture flow-type smart manufacturing systems. A digital twin system is developed to enable the remote semi-physical commissioning. The proposed approach is validated through a case study of digital twins-based remote semi-physical commissioning of a smartphone assembly line. The results showed that combining the open architecture design paradigm with the proposed digital twins-based approach makes the commissioning of a new flow-type smart manufacturing system more sustainable. [ABSTRACT FROM AUTHOR]

This paper presents a comprehensive system for assessing contaminant emissions, including the dominant contaminant reduction effects, recessive contaminant reduction effects, and contaminant reduction efficiency indexes. The system is used to evaluate the linkage changes in contaminant emissions reduction across different sectors, the ease of regulation, and the returns on emissions reduction efforts. The study's results demonstrate that firstly, COVID-19 initially reduced contaminant emissions across almost all sectors, although this effect waned over time. Secondly, applying conventional regulatory measures to sectors with high reductions in contaminant emissions may not yield the expected results. Thirdly, while some sectors may be more difficult to regulate, they may offer a higher return on investment in terms of emissions reduction. Based on the above results, the paper advocates for timely measures to consolidate environmental gains, prevent rebounding of contaminant emissions, prioritize supervision and management of easily regulated sectors, prioritize upgrading of cleaner production in sectors with high reduction efficiency indices, and increase investment in environmental technology. • Created a new comprehensive system for assessing contaminant emission changes. • Quantified the unique linkage changes of contaminant emissions during COVID-19. • Developed new models to reveal contaminants' regulatory difficulty and return. • The innovative reduction effects of four key contaminant indicators were measured. • Applied WHEM firstly in research across multiple areas of contaminant emissions. [ABSTRACT FROM AUTHOR]

This paper investigates the causal effect of COVID-19 quarantine measures on the electricity consumption of different types of regulated customers. In particular, the average energy consumption of a group of customers in Chile is examined, exploiting the weekly variations in the application of the stages of the Step by Step Plan as a natural experiment. Step by Step Plan was the Chile COVID containment strategy, which involved implementing partial lockdowns based on the COVID incidence in the municipalities, and adjusted on a weekly basis. An econometric model is specified, and estimated using the technique Difference-in-Difference-in-Difference (DDD) to quantify the causal impact of these measures. After applying the model, it is found that the quarantine measures have had a negative effect on the trend weekly consumption of customers located in municipalities where some of the phases of the Plan have been applied. This effect is significantly different depending on each stage of the plan analysis, and statistically significant. It is also observed that, on average, the savings for a representative customer in the sample range from $ 8 to $ 6. 15 for some municipalities, and the sample costs range from $ 0. 02 to $ 0. 26 for others, depending on the municipality analyzed. The results can be expressed in a total of 2.95 tons less CO 2 emitted on a monthly basis. This shows a great impact in terms of sustainability and planning of energy demand and supply. • Quarantines by Covid 19 affected energy consumption, like a "Natural Experiment". • Using Panel Data of 400 thousand observations with geographic, temporal and Daylight Saving Time controls. • Difference-in-Difference-in-Difference method to quantify causal impact of quarantines on electric consumption. • Applying quarantines generated Energetic Savings from 8 cents to 6.15 dollars depending on client type. • An Event Study was designed to check the estimation results. [ABSTRACT FROM AUTHOR]

Resilience has a critical role to promote human well-being in turbulent environments. However, extensive interventions and stimulus measures not only achieve resilience goals with numerous unacceptable consequences, but also highlight the narrow definition of resilience. The study proposes the concept of resilience effectiveness to constrain the unsustainability of resilience in concept and practice. The resilience effectiveness of Chinese cities in the early stages of the pandemic is first implemented for evaluation based on input-output relationship, and then patterns and determinants are investigated using the GIS methods and the geographically optimal zones-based heterogeneity (GOZH) model. The study finds that the average resilience effectiveness is not high, indicating that China's strong resilience is the loss of safety, greenness, inclusiveness, and efficiency in the early stage of the pandemic. Resilience effectiveness has significant spatial heterogeneity and is dominated by innovation ability. The optimal geographic zones of Chinese cities for resilience effectiveness are identified, revealing that it is a complex and multifactorial process. This paper broadens resilience research and provides implications for city planning in the post-pandemic era. [ABSTRACT FROM AUTHOR]

A safe and effective medical waste transport network is beneficial to control the COVID-19 pandemic and at least decelerate the spread of novel coronavirus. Seldom studies concentrated on a two-phase COVID-19 medical waste transport in the presence of multi-type vehicle selection, sustainability, and infection probability, which is the focus of this paper. This paper aims to identify the priority of sustainable objectives and observe the impacts of multi-phase and infection probability on the results. Thus, such a problem is formulated as a mixed-integer programming model to minimise total potential infection risks, minimise total environmental risks, and maximise total economic benefits. Then, a hybrid solution strategy is designed, incorporating a lexicographic optimisation approach and a linear weighted sum method. A real-world case study from Chongqing is used to illustrate this methodology. Results indicate that the solution strategy guides a good COVID-19 medical waste transport scheme within 1 min. The priority of sustainable objectives is society, economy, and environment in the first and second phases because the total Gap of case No.35 is 3.20%. A decentralised decision mode is preferred to design a COVID-19 medical waste transport network at the province level. Whatever the infection probability is, infection risk is the most critical concern in the COVID-19 medical waste clean-up activities. Environmental and economic sustainability performance also should be considered when infection probability is more than a certain threshold. • Two-phase COVID-19 medical waste transport with infection probability is studied. • A mixed-integer programming model to optimise sustainability is formulated. • A hybrid solution strategy is designed to solve the proposed multi-objective model. • The priority of sustainable objectives is society, economy, and environment. [ABSTRACT FROM AUTHOR]

This paper examines the impact of COVID-19 on marginalised communities and its effects on the provision of public services. Focusing on two coal mining regions in Colombia during the pandemic crisis, and examining Indigenous and Afro-Colombian communities, we analyze the provision of public services at a local level, identifying both shortcomings and resilience. Findings show that the lack of resilient public services amplified the effects of COVID-19 and its containment measures, exacerbating existing structural inequalities within local marginalised communities. It also reinforced the control exercised by coal mining companies within local economies. However, the substantial lack of public service provision also provided space for the development and strengthening of several resilience strategies among local communities, such as solidarity networks and schemes and the revitalization of local environmental knowledge. The study identifies multiple shortcomings in how the national and local administrations handled the COVID-19 outbreak and highlights the potential of enhancing resilience in public services to support marginalised communities in times of crisis. • COVID-19 affected the delivery of public services at a national and local level in Colombia. • COVID-19 further aggravated living conditions of mining communities in the country. • Multinational companies replaced the government in delivering services to mining communities. • But the crisis gave an incentive to these communities to adopt resilient strategies themselves. • More resilient public services in Colombia are needed to help marginalised communities. [ABSTRACT FROM AUTHOR]

As a rapidly expanding type of shared mobility, bike sharing is facing severe challenges of bike over-supply and demand fluctuation in many Chinese cities. In this paper, a large-scale method is developed to determine the minimum fleet size under future demand uncertainty, which is applied in a case study with millions of bike sharing trips in Nanjing. The findings show that if future uncertainty is not considered, more than 12% of trip demands may not be satisfied. Nevertheless, the proposed algorithm for minimizing fleet size based on historical trip data is effective in handling future uncertainty. For a bike sharing system, supplying 14.5% of the original fleet could be sufficient to meet 96.8% of trip demands. Meanwhile, the results suggest a unified platform that integrates multiple companies can significantly reduce the total fleet size by 44.6%. Moreover, in view of the Coronavirus Disease 2019 (COVID-19) pandemic, this paper proposes a contact delay policy that maintains a suitable usage interval, which results in increased bike amount requirements. These findings provide useful insights for improving resource efficiency and operational services in shared mobility applications. [Display omitted] • Our method can minimize the fleet size for millions of trips in large size networks. • Our improved algorithm can handle the uncertainty of future trip demands. • Supplying 14.5% of the original fleet can meet 96.8% of dockless bike sharing trips. • A contact delay policy is proposed and tested for the COVID-19 pandemic response. • Integrating multiple companies into a unified platform can reduce fleet size. [ABSTRACT FROM AUTHOR]

This paper examines the risk transmissions across the green economy indices of three major regions which include US, Europe and Asia. The econometric analyses are conducted using DCC-GARCH and TVP-VAR connectedness approach to evaluate potential spillover effects within the context of oil and gold. Results indicate that green economy indices of US-Europe exhibit the greatest time-varying correlations among the three pairs during much of 2010–2022 consistent with that of the general equity market. However, co-movements during the COVID-19 pandemic period seem to display a change in pattern for green economy indices. The strength of the co-movements between the US and Europe displayed a declining trend, while that between US and Asia was strengthened, suggesting greater interdependence between these two markets. TVP-VAR connectedness analysis revealed that US and Europe dominate the transmission of the shocks across the years in the green economy, similar to that of the equity markets. However, during the pandemic a pronounced shift occurred in green economies when considering the risk transmissions within the context of commodities: oil and gold. While Asian green economy index was persistently a receiver of risk transmission from oil unlike the other two regions, since pandemic, oil displayed an asymmetric effect and has become the net transmitter of risk in negative returns of the green economies of US and Europe. This may reflect the diversion in environmental policies of the two regions in the recent past, and point to the dominance of energy sector in the green economy. These findings have substantial implications for the development of green economy policies and from an investment perspective. [ABSTRACT FROM AUTHOR]

This paper examines the risk transmissions across the green economy indices of three major regions which include US, Europe and Asia. The econometric analyses are conducted using DCC-GARCH and TVP-VAR connectedness approach to evaluate potential spillover effects within the context of oil and gold. Results indicate that green economy indices of US-Europe exhibit the greatest time-varying correlations among the three pairs during much of 2010–2022 consistent with that of the general equity market. However, co-movements during the COVID-19 pandemic period seem to display a change in pattern for green economy indices. The strength of the co-movements between the US and Europe displayed a declining trend, while that between US and Asia was strengthened, suggesting greater interdependence between these two markets. TVP-VAR connectedness analysis revealed that US and Europe dominate the transmission of the shocks across the years in the green economy, similar to that of the equity markets. However, during the pandemic a pronounced shift occurred in green economies when considering the risk transmissions within the context of commodities: oil and gold. While Asian green economy index was persistently a receiver of risk transmission from oil unlike the other two regions, since pandemic, oil displayed an asymmetric effect and has become the net transmitter of risk in negative returns of the green economies of US and Europe. This may reflect the diversion in environmental policies of the two regions in the recent past, and point to the dominance of energy sector in the green economy. These findings have substantial implications for the development of green economy policies and from an investment perspective. [ABSTRACT FROM AUTHOR]

As a result of the COVID-19 pandemic, supply chains (SCs) have been exposed to their greatest disruption in recent memory. This unprecedented situation has given rise to the concept of SC survivability, which is based on the need to find a new temporary equilibrium allowing SCs to survive during extreme events. The purpose of this paper is to contribute to the conceptualization of SC survivability by providing some basic foundations for this new concept. Our analysis shows that dealing with SC survivability requires a larger scale than those adopted for the analysis of SC resilience. To solve this issue, we propose a new framework called "Human Needs Supply chains". This framework shows the interdependencies between SCs, society, and the environment and enables a shift from the classical SC's product-profit view to a holistic view centred on the satisfaction of basic human needs. Another contribution of this research is to highlight the links between SC survivability, SC resilience, and SC sustainability. We show that the classical resilience capacities (i.e., absorptive, adaptive, and restorative) are not enough to deal with extraordinary and long-term disruptions such as COVID-19, and we propose an adaptation of the SC resilience concept to integrate a survivability capacity. Building resilience with a survivability capacity will allow SCs to stay alive in a temporary non-viable equilibrium of sustainability during a large disruption and to recover to a viable equilibrium at the end of the crisis. [ABSTRACT FROM AUTHOR]

The COVID-19 pandemic lockdowns led to a sharp drop in socio-economic activities in China in 2020, including reductions in fossil fuel use, industry productions, and traffic volumes. China's economy suffered a serious negative effect from COVID-19. However, there is a "positive effect" on CO 2 emissions reduction. Here, for the first time, this paper constructs a new model named "Weighted Multi-regional Hypothetical Extraction Method (WMHEM)" based on a multiregional input-output model. It not only solves the problems of traditional HEM methods such as improper use of assumptions, excessive reliance on industry intermediate input, but also accurately reflects the impact of external shocks on the inter-industry linkages. By using the monthly economic data of each provinces in China during COVID-19 (except Hong Kong，Macao and Taiwan) an the latest Multi-regional input-output tables, the "economic negative effect" and "CO 2 emission positive effect" under COVID-19 in China are measured. Results show that COVID-19 lockdown was estimated to have reduced China's CO 2 emissions substantially between January and March in 2020, with the largest reductions in February. With the spread of coronavirus controlled, China's CO 2 emissions rebounded in April. In addition, key emission reduction sectors and key development encouraged sectors are selected by combining "economic negative effect" and "CO 2 emission positive effect" during COVID-19. Therefore, policies recommendations are put forward based on forward and backward linkages respectively which are from two ends of the supply chain to turn pandemic-related CO 2 emissions declines into firm climate action. • COVID-19 has negative effects on economy, but positive effects on CO 2 emissions. • A new model is used to measure economic and CO 2 emission effects during COVID-19. • Hubei had the biggest economic and CO 2 emission effects on China due to COVID-19. • Economic and CO 2 emission effects of COVID-19 are combined to select key sectors. [ABSTRACT FROM AUTHOR]

The COVID-19 pandemic not only poses an unprecedented threat to global health but also severely disrupts the natural environment and ecosystems. Mitigating the adverse impacts of plastic-based personal protective equipment (PPE) waste requires the cooperation of professionals from various fields. This paper discusses a novel, cleaner approach to soil stabilisation by repurposing the nitrile gloves into a sustainable road material to improve the mechanical properties of expansive clay soil as pavement subgrade. For the first time, extensive geotechnical testings, including standard compaction, unconfined compressive strength (UCS), unsoaked California bearing ratio (CBR), repeated load triaxial (RLT), and swelling-shrinkage tests, were carried out to investigate the engineering performance of different proportions of the shredded nitrile gloves (SNG) (e.g., 1%, 1.5%, 2%) were blended with expansive clay (EC). In addition, surface roughness, scanning electron microscopy (SEM), and X-ray micro-CT analyses were conducted, and images were obtained to study the microstructural modification of the EC-SNG mixtures. The experimental results indicated that the blend of expansive clay with SNG helped in increasing the compressive strength, resilient modulus, and CBR and assisted in reducing the swelling and shrinkage of the soil. SEM and surface roughness analyses indicated the interaction between the soil matrix interface and the rough surface of the SNG. The main reasons for increasing the strength and stability of clay soil could be attributed to the high tensile strength of the SNG and the formation of the three-dimensional grid, and friction between the soil particles and SNG. According to the X-ray micro-CT test results, the incorporation of SNG led to an increase in closed porosity. [Display omitted] • An innovative approach to mitigate the problem of medical waste generation associated with COVID-19 is presented. • A cleaner and sustainable subgrade was developed by using discarded nitrile gloves. • The addition of 1.5% SNG to the soil provided the highest strength properties. • SNG reduced the swelling and shrinkage of the expansive clay subgrade. [ABSTRACT FROM AUTHOR]

This paper investigates whether or not Italian Certified B Corps® in the fashion industry achieved levels of corporate social responsibility (CSR) and financial performance that are comparable to listed companies in the same industry during the Covid-19 pandemic. After a review of the literature concerning B Corps, CSR and the circular economy, as well as some coverage of pandemic impacts, a quantitative approach is used to analyze the data empirically. Based on the data available, the study incorporated the entire population of Italian listed companies and B Corps in the fashion industry. Moreover, this study confirms the relationship between CSR and financial performance. The availability of sustainability documents other than the required social responsibility report does not directly affect a company's profitability, but they are necessary for the long term. The results also confirm the positive relationship between sustainability certification and higher financial performance, as the most sustainable companies were also the most profitable. Certified B Corps® declare their willingness to adopt circular economic principles to the same extent as non-certified listed companies. Moreover, the results show that consumers mainly remember the information disclosed on a company's homepage; therefore, managers should publish more there. However, they should not underestimate the importance of their sustainability report because it is an effective social communication tool, especially in the long term. Finally, obtaining the B Corp certification will allow companies to inform stakeholders of their social responsibility and achieve higher financial results. [ABSTRACT FROM AUTHOR]

Achieving the peak of carbon dioxide (CO 2) emissions requires a large amount of green and low-carbon investment. Whether the green finance system can efficiently support the capital need for achieving the CO 2 emissions target in the context of the COVID-19 epidemic is a matter of concern. This paper constructs a system dynamics model (SD model) to illustrate the quantitative relationship between the green finance system and CO 2 emissions and introduce the COVID-19 epidemic as a variable to analyze ten simulation scenarios regarding the carbon emissions commitment realization under different green finance and economic growth status. It is shown that: (1) Regardless of the impact of COVID-19, China can meet its commitment by reaching its CO 2 emissions peak in 2030 and realizing a 20% non-fossil energy proportion in 2025; (2) Under the impact of the epidemic, the goal can not be obtained in all energy consumption scenarios when the government expenditure on the environment is low. The target year of reaching CO 2 emissions peak becomes 2033, 2037, and 2040. The results indicate that reducing government expenditure on environment protection makes the CO 2 emissions peak target less likely to be achieved within a given time frame. We also concluded with important policy implications according to the result of the simulations. Overall, this study makes a reference for other economies and researchers to quantitatively predict the interaction relationship between the green finance system and CO 2 emissions in the context of COVID-19, which provides policymakers with insights into a joint power of energy consumption upgrading and green capital guidance. • Providing empirical studies regarding the mechanism of the inhibitory effect of green finance on CO 2 emissions. • Using systems dynamics model to address the missing data problem. • Making solid suggestions under COVID-19 Epidemic. • Building the relationship between the green finance system and CO 2 emissions and making forecasts for "3060" mission result. [ABSTRACT FROM AUTHOR]

COVID-19 pandemic has shown that sustainable development of energy, water and environment systems is essential for the basic life needs of humankind. Logistics problems, shortage of resources and goods, a crisis of traditional energy systems, all these COVID-19 caused problems show that available resources should be used with caution. This paper is an introduction article to the Virtual Special Issue that discusses some of the latest developments in three research topic areas, namely Energy, Water and Environment. These research topics emerged from the four Sustainable Development of Energy, Water and Environment Systems Conferences held in 2020. The purpose of the introduction article is to provide a brief introduction to the field and the articles included in this Journal of Cleaner Production Virtual Special Issue. [ABSTRACT FROM AUTHOR]

While the deployment of technological innovation was able to avert a devastating global supply chain fallout arising from the impact of ravaging COronaVIrus Disease 19 (COVID-19) pandemic, little is known about potential environmental cost of such achievement. The aim of this paper is to identify the determinants of logistics performance and investigate its empirical linkages with economic and environmental indicators. We built a macro-level dataset for the top 25 ranked logistics countries from 2007 to 2018, conducting a set of panel data tests on cross-sectional dependence, stationarity and cointegration, to provide preliminary insights. Empirical estimates from Fully Modified Ordinary Least Squares (FMOLS), Generalized Method of Moments (GMM), and Quantile Regression (QR) model suggest that technological innovation, Human Development Index (HDI), urbanization, and trade openness significantly boost logistic performance, whereas employment and Gross Fixed Capital Formation (GFCF) fail to respond in such a desirable path. In turn, an increase in the Logistic Performance Index (LPI) is found to worsen economic growth. Finally, LPI exhibits a large positive effect on carbon emissions, which is congruent with a strand of the literature highlighting that the modern supply chain is far from being decarbonized. Thus, this evidence further suggest that more global efforts should be geared to attain a sustainable logistics. • Examining 25 topmost Logistics Countries on many fronts. • Technological innovation, HDI, urbanization, and trade openness spur logistic performance. • Logistic performance does not improve with employment rate and Gross Fixed Capital Formation. • Logistic performance increases carbon dioxide emissions. [ABSTRACT FROM AUTHOR]

The COVID-19 pandemic has not only caused a global health crisis, but it has also had significant environmental and human consequences. During the COVID-19 pandemic, this study focused on emerging challenges in managing healthy personal protective materials (HPPM) in Kingdom of Saudi Arabia, using silty sand (SM) soil as an example since it covers large areas in KSA and in the whole world. The main objective of this paper is to find a novel way to minimize pandemic-related waste by using HPPM as waste materials in road construction. For the first time, a series of experiments was conducted on a mixture of different percentages of shredded HPPM (0, 0.5, 1 and 2%) added to the silty sand (SM) soil for road applications, including soil classification according to the USCS, modified compaction, UCS, UPV, and CBR. In addition, a numerical simulation was performed using geotechnical-based software Plaxis 3D to study the performance of the soil-HPPM mix as a subbase layer in the paving structure under heavy traffic loading. The modified compaction test results show that there is an increase in the optimum moisture content with increasing the HPPM contents from 0.5% to 1% and 2%. However, a reduction in the maximum dry density is observed. The values of dry density and water content at 0%, 0.5%, 1% and 2% pf HPPM are 2.045, 1.98, 1.86 and 1.8 g/cm3 and 7.65% 8%, 8.5% and 9.5%, respectively. The soaked CBR values at 0, 0.5, 1 and 2% HPPM are 23, 30, 8, 2% with the maximum value attained with the addition of 0.5% HPPM. The results of UCS were with the same percentages of HPPM 430, 450, 430 and 415 kPa, respectively, with the maximum value attained with 0.5% HPPM addition as well. In contrast, the values of UVP at 0%, 0.5%, 1% and 2% are 978.5, 680.3, 489.4 and 323.6 m/s, respectively, confirming the trends obtained by modified compaction test results. The simulation results confirm this conclusion that the soil-HPPM mix show a superior performance when used as a subbase layer and reduced vertical displacement by a percentage of 11% compared to the normal subbase material. By eliminating HPPM especially facemasks from the landfill lifecycle, incorporating them into high quality construction material production has the potential to deliver significant environmental benefits. [Display omitted] 1 Influence of polypropylene (HPPM) fibres on the performance of sandy soil is clearly studied. 2 The optimum fibres content is obtained as 0.5% volume fraction. 3 Positive improvement is also noticed in unconfined compressive strength and compaction after adding HPPM fibres. 4 Fibres play a major role in crack bridging. [ABSTRACT FROM AUTHOR]

The onset of 2020 is marked by stricter restrictions on maritime sulfur emissions and the spread of Coronavirus Disease 2019 (COVID-19). In this background, liner companies now face the challenge to find suitable sulfur reduction technologies, make reasonable decisions on fleet renewal, and prepare stable operation plans under the highly uncertain shipping market. Considering three sulfur reduction technologies, namely, fuel-switching, scrubber, and liquefied natural gas (LNG) dual-fuel engine, this paper develops a robust optimization model based on two-stage stochastic linear programming (SLP) to formulate a decision plan for container fleet, which can deal with various uncertainties in future: freight demand, ship charter rate, fuel price, retrofit time and Sulfur Emission Control Area (SECA) ratio. The main decision contents include ship acquisition, ship retrofit, ship sale, ship charter, route assignment, and speed optimization. The effectiveness of our plan was verified through a case study on two liner routes from the Far East to Northwest America, operated by COSCO Shipping Lines. The results from SLP model show that large-capacity fuel-switching ships and their LNG dual-fuel engine retrofits should be included in the long-term investment and operation plan; slow-steaming is an important operational decision for ocean liner shipping; if the current SECA boundary is not further expanded or the sulfur emission restrictions not further tightened, the scrubber ship will have no advantage in investment cost and operation. However, considering the probabilities of more flexible scenarios, the results from the robust model suggest that it is beneficial to install scrubber on medium-capacity fuel-switching ships, and carry out more LNG dual-fuel engine retrofits for large-capacity fuel-switching ships. Compared with SLP, this robust strategy greatly reduces sulfur emissions while slightly pushing up carbon emissions. • A robust optimization model was established based on two-stage stochastic linear programming. • Three sulfur reduction technologies were integrated into fleet renewal decisions. • Various uncertainties in liner shipping market amidst COVID-19 were considered. • Strategic and tactical decisions were optimized at the same time. • A real case of COSCO-Liner under the influence of COVID-19 is studied to demonstrate the effectiveness. [ABSTRACT FROM AUTHOR]

The COVID-19 virus in a short time has caused a terrible crisis that has been spread around the world. This crisis has affected human life in several dimensions, one of which is a sharp increase in urban waste. This increase in waste volume during the pandemic, in addition to the intense increase in costs associated with the risks of virus contagion through infectious waste. In this study, a hybrid mathematical modelling approach including a Bi-level programming model for infectious waste management has been proposed. At the higher level of the model, government decisions regarding the total costs related to infectious waste must be minimized. At this level, the collected infectious waste is converted into energy, the revenue of which is returned to the system. The lower level relates to the risks of virus contagion through infectious waste, which can be catastrophic if ignored. This study has considered the low, medium, high and very high prevalence scenarios as key parameters for the production of waste. In addition, the uncertainty in citizens' demand for waste collection was also included in the proposed model. The results showed that by energy production from waste during the COVID-19 pandemic, 34% of the total cost of collecting and transporting waste can be compensated. Finally, this paper obtained useful managerial insights using the data of Kermanshah city as a real case. [Display omitted] [ABSTRACT FROM AUTHOR]