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This paper addresses the two-stage hybrid flow shop scheduling problem with a batch processor in the first stage and a discrete processor in the second stage. Incompatible job families and limited buffer size are considered. This hybrid flow shop configuration commonly appears in manufacturing operations and the batch processor is always the bottleneck which breaks the symmetry of processing time. Since making a real-time high-quality schedule is challenging, we focus on the automatic design of efficient heuristics for this two-stage problem based on the genetic programming method. We develop a hyper-heuristic approach to automate the tedious trial-and-error design process of heuristics. The goal is to generate efficient dispatching rules for identifying complete schedules to minimize the total completion time. A genetic programming with cooperative co-evolution approach is proposed to evolve the schedule policy automatically. Numerical results demonstrate that the proposed approach outperforms both the constructive heuristic and meta-heuristic algorithms, and is capable of producing high-quality schedules within seconds. [ABSTRACT FROM AUTHOR]

Abstract Suppliers' adoption of sustainable practices plays a critical role for global companies to improve environmental performance. Based on the absorptive capacity theory, this study empirically explores how suppliers' knowledge bases and power relationships influence their adoption of sustainability practices. A longitudinal case study with eight suppliers has been conducted. We find that the adoption of leading sustainable practices requires a supplier's good knowledge base whereas a supplier can adopt imitating and toddling sustainable practices even if it has a limited knowledge base. Both the power of internal sustainability teams and external buyers enhance the effects of suppliers' knowledge bases on the adoption of sustainable practices. Suppliers choose the strategy used in adopting sustainable practices according to the configuration of internal and external power. The results enhance the current understandings of the mechanisms through which knowledge bases and power relationships affect the adoption of sustainable practices. The findings can also help global companies improve the effectiveness of their supplier development efforts and enhance the environmental performance of supply chains. Highlights • Absorptive capacity is crucial for environmental management performance. • A supplier's knowledge base is critical for adoption of sustainable practices. • The power of sustainability team will enhance the effect of good knowledge base. • The power of dominant buyer will enhance the effect of good knowledge base. • Internal and external power outlines the env. management strategy of suppliers. [ABSTRACT FROM AUTHOR]

In this article the authors discuss the results of a study of the Chinese population in which many of those surveyed were concerned about urban air pollution or its health effects. The authors argue that despite the survey's results, ways to manage urban air quality through monitoring, information, and participatory approaches remains unresolved. Topics include the public perception about urban air quality and environmental information in China, the power of information, and social change.

Pakistan is a resource-constrained country facing severe power shortages. To address the power demand-supply gap, Pakistan has increased its use of fossil fuel energy sources for power generation. To support a lower carbon power supply Pakistan needs renewable energy sources such as hydropower. However, most of the water for irrigation and power generation in the country is derived from a watershed in a disputed territory shared between India and Pakistan. Construction of hydroelectric dams over transboundary rivers have led to concerns regarding their ecological impacts. In this paper, we evaluated the sustainability of the Bursar Hydroelectric Project, proposed on such a transboundary river. Emergy analysis was used to holistically determine the change in the intrinsic value of the local ecosystem both before and after the construction of the dam. The results show that the project would increase the qualitative value of outputs derived from the local ecosystem. However, it would also extract and stock significant resources thus decreasing the overall sustainability of the system. In conclusion, the construction of the subject dam has negative consequences for unrestricted flow of water, sediments and biomass downstream. Policy makers can use this study to design mitigation measures for ecological conservation. [ABSTRACT FROM AUTHOR]

Over the past few decades, the pollutant emissions trading policies in China have undergone significant innovation and exploration. It is considered as a market-based approach that became integrated with command-and-control mechanisms such as total emissions control or pollution permits. This study is the first to provide systematic, reflective thinking that tracks the regional initiatives of pollutant emissions trading systems in China. In this article, we divided China's emissions trading practices into three stages and conducted a comparative qualitative analysis of the country's eleven provincial emissions trading pilots. We found that provincial pilots are highly diverse and complex regarding the pollutants that can be traded, the industrial sectors involved, the design of trading administration and processes, and the implementation of trading practices such as allowance, pricing and platforms. We also identified four main challenges: legislation setup, monitoring and verification, administrative interference, and the technical quantification of pollutant hotspots. We conclude the article by providing policy implications so that emissions trading policies can be integrated with the newly developed pollution permitting system. • Pollutants emission trading systems in China have been shaped at regional level instead of central. • 11 provincial pilots of PETS have high diversity and complexity thanks to socio-economic variey. • PETS faces challenges such as legislation setup, monitoring, and administrative interference. [ABSTRACT FROM AUTHOR]

Environmental incidents are among the most significant environmental challenges in China. Hundreds of environmental incidents occur every year, endangering human health and ecosystems. In this paper, we conducted an analytical study of environmental incidents from 2006 to 2015 in China. We first examined the spatiotemporal characteristics of the total 5213 incidents based on the statistical data collected from the China Statistical Yearbook on Environment . We then examined the characteristics of the sources of risk, causes of harm and resulting damage of environmental incidents based on first-hand data from 1369 cases collected by the Ministry of Environmental Protection (MEP) of China, which obtains detailed incident information. The results show that (1) there was a significant downward trend in the overall number of environmental incidents between 2006 and 2015, and developed eastern regions were high incidence areas; (2) hazardous chemicals were the main risk stressors; (3) production safety accidents and traffic accidents were the two major causes, and (4) most of these incidents resulted in polluted water and air. This paper is the first to provide a longitudinal analysis of the full scope of environmental incidents across the different regions of China, which has useful implications for policy-making and environmental management. [ABSTRACT FROM AUTHOR]

Food system resilience has multiple dimensions. We draw on food system and resilience concepts and review resilience framings of different communities. We present four questions to frame food system resilience (Resilience of what? Resilience to what? Resilience from whose perspective? Resilience for how long?) and three approaches to enhancing resilience (robustness, recovery, and reorientation—the three "Rs"). We focus on enhancing resilience of food system outcomes and argue this will require food system actors adapting their activities, noting that activities do not change spontaneously but in response to a change in drivers: an opportunity or a threat. However, operationalizing resilience enhancement involves normative choices and will result in decisions having to be negotiated about trade-offs among food system outcomes for different stakeholders. New approaches to including different food system actors' perceptions and goals are needed to build food systems that are better positioned to address challenges of the future. [ABSTRACT FROM AUTHOR]

• Localized structural equation models are estimated for the 13 cities of Jiangsu. • Residents' intentions to participate in source separation and recycling are quantified. • Main influencing factors and their degrees of influence are identified across cities. • Tailored and localized management strategies are proposed. Source separation and recycling (SSR) for municipal solid waste is an important strategy for the transition to a circular economy and requires broader resident participation. How can residents' participation in SSR be promoted? Here, we consider 13 cities in Jiangsu as microcosms of China. We quantify residents' intentions to participate in SSR by distributing a validated questionnaire to 2,963 urban residents, analyze the results through structural equation modeling, and propose localized policy recommendations. We find that residents have positive attitudes toward SSR, although 92.6% of residents in southern Jiangsu were more willing to participate than those in northern Jiangsu (84.6%). Additionally, the influencing factors and their degree of influence on resident SSR participation intentions exhibit disparities across cities. "Accessibility of SSR facilities" simultaneously affects the 13 studied cities and is a key factor. "Environmental knowledge" and "environmental attitudes" are important impact factors, with occurrence frequencies of 84.6% and 69.2%, respectively. However, laws and regulations have no significant effect on residents' SSR participation intentions. We recommend that the government create favorable external conditions related to facilities and services, promote extensive publicity and educational activities through various channels, and improve the effectiveness of SSR laws and regulations. Future SSR management strategies should be localized, flexible and comprehensive. This research could help decision makers in China and other countries design policy guides to promote SSR and help link current research areas to social development. [ABSTRACT FROM AUTHOR]

Recycling is an essential practice for the successful operation of zero waste cities. It is essential to understand the recyclable waste recycling potential (RWRP). This study quantifies the RWRP of different cities in China. Suzhou, Yangzhou, and Suqian represent high-, middle- and low-income cities, respectively. The RWRP statistics are based on systematic multiple longitudinal tracking field surveys conducted between 2016 and 2019. Obvious RWRP spatio-temporal disparities were observed between inter-city and intra-city. For instance, Suzhou showed a slight increase in high resource value paper; Yangzhou had a slight increase in low resource value paper; and Suqian had a huge increase in no resource value paper and plastic. Additionally, more recyclable organics were generated in the old districts of Suzhou, and they were also predominant in the new districts of Yangzhou. No significant difference was observed in recyclable organics and recyclable material in Suqian. However, recyclable organics is a constant, while recyclable material fluctuates in the case cities. Household consumption structure has a major impact on RWRP. Other factors, such as economic development, urban resident population, consumption preferences, local customs and culture, as well as residential lifestyles also affect RWRP. This study proposes three policies: 1) to establish flexible and carefully planned recycling strategies, 2) to develop the distribution market of composting products, and 3) to incorporate economic and demographic initiatives to develop a workable recycling policy that can lead to zero waste implementation in the future. The zero waste concept was further assessed by the authors' review of 69 cities worldwide based on previous research. We compared past results with the three featured cities in this study and 35 other Chinese cities, thereby presenting a world view of zero waste potential. It is anticipated that representative cities' RWRP quantification and policy implementations can be a model for municipal solid waste management and recycling policies in other Chinese cities, which will help them transition to zero waste cities and probably provide a model for cities worldwide. [Display omitted] • A longitudinal survey was performed in 3 cities with different income levels. • Recycling potential and recyclable waste stream generation were quantitated. • Spatiotemporal disparity effects on recycling potential are discussed. • Practical recycling policies are suggested with zero waste goals in the future. [ABSTRACT FROM AUTHOR]

Over the past 20 years, the spatial distribution of electrical generation and its relationship to cross-regional power transmission has impacted China's power generation system and significantly affected the total amount of NO x and the aggregated nitrogen oxides intensity (ANI) of the system. An investigation of the driving mechanisms of ANI that considers the unevenness of regional electricity generation will be crucial to future improvements in the NO x efficiency of the electrical generation system in China. In this study, we built a decomposition model for ANI by incorporating the spatial distribution of electrical generation and found that the spatial distribution of electricity generation together with energy-related factors gradually caused decreases in ANI. The efficiency of electricity generation presented the dominant inhibitory effect on ANI, but its effect size has weakened since 2010. In contrast, the fossil fuel structure of thermal power shows an increasingly positive effect on changes in ANI. The primary energy composition only slightly affected changes in ANI. Moreover, the changed geographical distribution of electricity generation is non-negligible and has a positive effect on reduction of the ANI of the Chinese electrical generation system. The transferred amount of local NO x emissions by cross-provincial electricity transmission, however, could cause lead to additional environmental costs for generators. This issue should receive more attention in the future. Highlights • The ANI of electrical generation has decreased by 33.18% over the past 20 years. • Electrical generation efficiency inhibited ANI strongly but gradually weakened over time. • The geographical distribution effect reduced the ANI but transferred environmental costs. • The electrical generation structure will hopefully affect ANI reduction in future. [ABSTRACT FROM AUTHOR]

In the West, limited government capacity to solve environmental problems has triggered the rise of a variety of “nonstate actors” to supplement government efforts or provide alternative mechanisms for addressing environmental issues. How does this development - along with our efforts to understand it - map onto environmental governance processes in China? China's efforts to address environmental issues reflect institutionalized governance processes that differ from parallel western processes in ways that have major consequences for domestic environmental governance practices and the governance of China “going abroad.” China's governance processes blur the distinction between the state and other actors; the “shadow of the state” is a major factor in all efforts to address environmental issues. The space occupied by nonstate actors in western systems is occupied by shiye danwei (“public service units”), she hui tuanti (“social associations”) and e-platforms, all of which have close links to the state. Meanwhile, international NGOs and multinational corporations are also significant players in China. As a result, the mechanisms of influence that produce effects in China differ in important ways from mechanisms familiar from the western experience. This conclusion has far-reaching implications for those seeking to address global environmental concerns, given the importance of China's growing economy and burgeoning network of trade relationships. [ABSTRACT FROM AUTHOR]

In China, nitrogen oxide (NOx) emissions have been declining in recent years, whereas NOx generation continues to increase. This has prompted a growing focus of policy design to inspect the driving mechanisms of NOx generation. In this study, a decomposition model of NOx generation in China from 1995 to 2014 was built using the Logarithmic Mean Divisia Index (LMDI) method. According to the decomposition results, technological effects (e.g., energy intensity and the sector generation factor) inhibited NOx generation in China, while gross domestic product (GDP) per capita was found to have the most positive effect on increasing NOx generation, accounting for 151.00% of the total change and showing an increasing trend in recent years. The sector structure of energy consumption always increased NOx generation, which contradicts the results of previous studies. All population effects considered in this study contributed to the growth in NOx generation. The population scale effect was increasingly impactful on the growth of NOx generation; the population spatial structure was active but less impactful. In general, technological impact cannot offset the increases caused by economic, structural, and population effects. Considering NOx reduction policy in China, more attention should be given to emission reduction policies, energy consumption, and socio-economic effects; together, these approaches will improve initiatives to reduce NOx. [ABSTRACT FROM AUTHOR]

China has modified its pollution control policy system with such price tools as the pollution charge (PC) policy and the payment for initial emission allowance (PIEA) policy. The aim of PC policy is to compensate for the environment damage caused by pollutants, while PIEA is in charge of the initial emission allowance (IEA) within the emission trading system (ETS). However, since the implementation of PIEA, it has been criticized as redundant because of the similar pricing scheme with the PC. In addition, the existing PIEA pricing approaches have ignored interactions with other policies, such as PC and total emission control (TEC) policies. In this research, we established an optimal control-based model with chemical oxygen demand (COD) and ammoniacal nitrogen (NH 3 -N), two independent pollutants variables, to simulate the water pollutants' PIEA price. Simulation results indicated that emission quantity and optimal social benefit in the PC–PIEA combination scenario was equal to the situation in the PIEA scenario. Under this design, PC compensated for the emission damage, and PIEA paid for the scarcity rent, while PIEA does not duplicate the PC policy. In addition, the PIEA policy has a complex effect on pollutant emission. Because PIEA policy increases the enterprises' discharging cost, most regions' COD emissions are less than the baseline, excepting Beijing, Shanghai, Jiangsu, Zhejiang, Fujian, Shandong, and Guangdong, in which emission quantities are greater than the baseline. The NH 3 -N emission shows an opposite trend. The simulation result is that excluding Inner Mongolia, Hubei, Hunan, Tibet, Gansu, Qinghai, Ningxia, and Xinjiang, the NH 3 -N emissions in the rest of regions are increased. TEC policy has a significant effect on pollutant emissions and the PIEA price. The COD emission quantity with TEC is lower than that without the TEC policy, therefore, the TEC policy will be effective for pollutant emission control. The pollutant beyond the restricted target will be charged a payment for IEA at a higher price than without the TEC policy. [ABSTRACT FROM AUTHOR]

Urban agriculture (UA), the growing of fruits and vegetables in urban and peri-urban areas, may improve food security and access, public health and dietary quality on both a broad and personal scale. However, there is little research on the relationship between UA and diet, and potential mediating factors are also unclear. This study aimed to investigate if proximity to and engagement with UA is associated with better diet quality, and what accounts for this relationship. UK-based adults (N = 583, 69% Female) completed measures of proximity to and engagement with UA, perceived access to fruits and vegetables, health and ethical food choice motivations, connection with nature, psychological distress and dietary quality in an online survey. Participants were recruited from UA-related groups and the general public. Proposed relationships were analysed using a structural equation model. Greater proximity to and engagement with UA was associated with greater perceived access to fruits and vegetables, more health-related food choice motivations, more ethical-related food choice, feeling more connected with nature, and, surprisingly greater psychological distress. Furthermore, proximity to and engagement with UA was indirectly associated with better diet quality via health-, and ethical-related, food choice motivations. While the direct pathway between proximity to and engagement with UA and diet quality was not significant, UA is associated with better diet quality, partly via healthier and ethical food choice motivations. Upscaling UA may have benefits for dietary quality via these factors, and more research is needed to test causal relationships and understand these complex interactions. [ABSTRACT FROM AUTHOR]

The increasing vehicle numbers in China have raised issues on effective mitigation of the vehicular NO x emissions recently. Notably, temporally growing and spatial agglomeration of high vehicular NO x emissions make an essential challenge to the mitigation strategy-makers. However, so far, there have been few studies to give insight into the socioeconomic drivers like the spatial imbalance of socioeconomic development, vehicle structure and road infrastructure to help governors. To fill the above gap, this study explores drivers of temporal change and spatial differences by building a temporal-spatial decomposition model and accounting for national and regional NO x emissions from vehicles in China from 2005 to 2015. Results show that, of all the driving forces in this study, only road vehicle carrying capacity (ΔN VI) acts as a primary driving force for both temporal growing and spatial agglomeration of vehicular NO x emissions in China. Regional vehicle emission intensity (ΔN NI) and road economic growth (ΔN EI) only mainly contributed to spatial agglomeration. While economic development (ΔN G) played a crucial role in the temporal growing of vehicular NO x emissions in China. These findings indicate that the future mitigation policy should fully cover the comprehensive socioeconomic factors, which would be useful for China and other developing countries when aiming to improve the performance of their current vehicle emissions policy system. Image 1 • China's NO x emissions from provincial vehicles were estimated during 2005–2015. • A new temporal-spatial decomposition model was built to identify emission drivers. • Road vehicle carrying capacity drives both temporal change and spatial difference. • Regional emission intensity and road economic growth affect spatial difference. • Economic development played a crucial role in the temporal change. [ABSTRACT FROM AUTHOR]

Emissions of NOx, a precursor to several atmospheric pollutants, are a crucial aspect of air pollution in China, which is closely related to its booming economy and high energy consumption. However, few studies explore the economic structure factors on NOx emissions from energy consumption, especially the spatial heterogeneity of economic drivers. To bridge the knowledge gap, this study adopts a structural decomposition analysis (SDA) to quantify and map the contributions of six drivers of China's NOx emissions from energy consumption (NEEC) between 2007 and 2012, which represent economic scale, economic structure, and energy consumption patterns. For China as a whole, the final demand scale and energy intensity factors increased NEEC, whereas economic structure factors showed an inhibiting effect. However, the change in provincial NEEC due to the production structure and product mix of the final demand varied in a large interval. A negative production structure accompanying a positive final demand product mix led to NEEC growth in metropolises like Beijing and Shanghai. Provincial disparities were dramatic within economic regions in eastern China, including the northwest, north coast, east coast, and south coast regions. These findings indicate that spatially differentiated economic structure and economic growth diversely featured the driving mechanism on provincial NOx emissions, which should be generally considered to make the different regional reduction policies in the future. Image 1 [ABSTRACT FROM AUTHOR]

Nitrogen oxides (NO x) has become the priority of China's air pollution control, but the regional socio-economic factors responsible for NO x generation are embedded with spatial disparities, which leads to different effects of air quality policy at the local level. This study applied a geographically weighted regression (GWR) model to investigate the drivers of NO x generation from energy consumption (NGEC) in China's 30 provinces, to explore nonstationary spatial effects of NGEC. The results showed that population size has always been the dominant factor in spatial NGEC across all regions of China, although there is a minor north-south difference. However, the effect of per capita GDP and energy intensity leads to a significant north-south difference when they are influencing NGEC, which shows a minor west-east difference from thermal power generation (TE). We also found that in Northern and Northeast China, the transition towards cleaner energy structure based on natural gas has started correlating significantly with NO x generation through a weakly negative effect in 2015. Our findings show alternative strategies on NO x reduction, which include the spatially differentiated effect of regional socioeconomic factors on energy consumption. • We examined spatially differentiated effects of NO x generation using GWR. • Economic growth and energy intensity showed the largest south-north spatial effects. • PS always dominantly affected spatial NGEC with a minor north-south difference. • NGR correlated significantly with NGEC through a weakly negative effect in 2015. • Spatially differentiated reduction policies need region-wise redesigning. [ABSTRACT FROM AUTHOR]