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Building, bridge or wind turbine maintenance requires manual dexterity tasks by a specialist rope-access trained workforce via two principal means: harness suspension of individual workers from above, or deployment of a suspended platform or cradle from which workers access the structure to be maintained. Currently no published research compares accuracy and efficiency of simulated maintenance tasks between these modalities. This study investigated manual dexterity task performance of peg placement and shape delineation in seated, standing and suspended environments in 16 healthy controls and 26 professional rope-access trained individuals. Both seated and standing assessments were superior to those suspended, and height of suspension, total mass and years of experience had no influence on the task outcome. These findings suggest that, where feasible, cradle suspension mechanisms which permit standing maintenance are favourable in terms of task efficacy and where feasible, should be considered for deployment in wind energy and other engineering applications.

Multistakeholder Meta-Organisations (MS-MOs) are often perceived as a ‘magic bullet’ that can tackle societal grand challenges in global supply chains. In this paper, we consider the case of the Roundtable on Sustainable Palm Oil (RSPO), and we investigate the extent to which an MS-MO reshapes the attribution of responsibility for sustainability in supply chains, especially in relation to underlying power dynamics. We conduct a multimodal critical discourse analysis of a broad range of sources, including videos and interviews. We show that through its discursive strategies, the RSPO allocates the responsibility for social and environmental issues to the two extremes of the supply chain: objectifying consumers at one end and smallholders at the other, hence reproducing and even exacerbating the traditional imbalanced power dynamics in supply chains. Our work contributes to the emerging, more critical strand of research investigating meta-organisations (MOs) and sustainable supply chain management.

Car-sharing services are developing at an ever-increasing pace. Taking into account the reduction of carbon dioxide emissions and pursuit of the sustainable development of transport, implementing electric cars in car-sharing fleets is being proposed. On the one hand, these types of vehicles are referred to as emission-free, but on the other hand, their environmental friendliness is questionable due to the emission of carbon dioxide during the production of energy to power them. Although many scientific papers are devoted to the issue of reducing emissions through car sharing, there is a research gap concerning the real production of carbon dioxide by car-sharing vehicles during car-sharing trips. To fill this research gap, the objective of the article was to analyze the actual level of carbon dioxide emissions from combustion and electric vehicles from car-sharing systems produced when renting rides. The test results showed that the electric car turned out to be significantly less emitting. The use of electric vehicles in car-sharing fleets can reduce carbon dioxide emissions from 14% to 65% compared to using cars with internal combustion engines. However, the key role during car-sharing trips is played by the driving style of the drivers, which has been omitted from the literature to date. This should be properly regulated by service providers and focus on the proper use of energy from electric vehicle batteries, especially at low temperatures. The article provides support for operators planning to modernize their fleet of vehicles and fills the research gap concerning car-sharing emissions.

Giant urban rail transit (GURT) systems have been formed in many metropolises and play a critical role in addressing serious traffic congestion. Unfortunately, as a dynamic and complex system, the vulnerability of GURT networks under various failure scenarios will be more prominent as the network expansion continues. Thus, it is imperative to explore the complex structural characteristics of the network and improve the ability to deal with the disturbance of emergencies. In this study, the destruction resistance of GURT networks with scale growth is illustrated from a vulnerability perspective. Specifically, taking Shanghai rail transit (SHRT) system as an example, the network topology model is constructed using the Space L method, and the network structure characteristics are analyzed based on the complex network theory. In addition, five attack strategies are developed to represent random and targeted attacks during the simulation of network failure, and two metrics are determined to evaluate the network vulnerability. Some meaningful results have been obtained: (i) The Shanghai rail transit planning network (SHRTPN) has increased the network efficiency by more than 10% over the Shanghai rail transit operating network (SHRTON) and has effectively enhanced the network destruction resistance. (ii) The SHRT network is a small-world network and shows significant vulnerability under the targeted attacks. The failure of only 3% high betweenness stations in SHRTON can lead to a 66.2% decrease in the network efficiency and a 75.8% decrease in the largest connected component (LCC) ratio. (iii) Attacking stations will cause more severe network failures than attacking edges, and it is necessary to focus on preventing catastrophic network failure caused by the critical station’s failure breaking the threshold. Finally, the strategies for improving the destruction resistance of GURT networks are proposed. The findings of this research can provide an essential reference for the rational planning, safety protection, and sustainable construction of GURT systems.

Although the United Nations’ Sustainable Development Goals (SDGs) advocate, through SDG 4 and SDG 10, equitable quality education and the reduction of inequalities within and between countries, respectively, few studies have examined how inequalities in regional sustainability influence higher education. Therefore, this study aims to examine the relationship between regional sustainability and higher education in China using fixed-effects panel modelling. A systematic force framework showing how regional sustainability drives higher education was constructed from economic, social, and environmental perspectives, and the endogeneity in the process of how regional sustainability affects higher education was explored by introducing one-year lagged values as instrumental variables. Our results show that regional sustainability has a significant impact on higher educational attainment in China, with differing effects in the eastern, central, and western regions, respectively. In central China, economic sustainability plays a significant positive role in higher educational attainment; in the western region, economic and social sustainability have stronger positive effects, while environmental sustainability has significantly negative effects. In terms of policy implications, our findings can be used to support regional development policies to promote regional higher education.

The aim of this study is to simulate the self-organized evolution mechanism of inner innovation of large-scale construction enterprises (LSCE) under different contexts. Based on NK stochastic combinatorial optimization model with two parameters (N, K), this study proposes three modules—ambidexterity, punctuated equilibrium, and automation—to simulate the change behaviors of the inner innovation system. Furthermore, this study analyses the influence of factor correlation on inner innovation performance under discusses nine different combination situations. The research results show that (a) regardless of how the relationship strength changes, fitness increases with an increasing K value; and (b) the comparison of optimization modes show that the punctuated equilibrium mode can guarantee the long- and short-term inner innovation performance LSCE. This study therefore reveals the mutual effects of the factors in the inner innovation system in LSCE and provides an effective model for internal systems analyses in the construction industry and in other sectors.

Abstract Numerous countries have set up strategic petroleum reserves (SPRs) in response to oil disruptions since 1970. While numerous studies model such programs, we found few that evaluate SPRs' historical performance. Thus, we evaluate the U.S. SPR's performance by comparing actual real costs with estimated real benefits. From 1976 to 2014, the real U.S. SPR cost was about $219 billion real (2014$) dollars, whereas the real benefit was only $122 billion. Sensitivity testing suggests such negative net benefits are qualitatively robust. However, if world oil demand is extremely inelastic to oil price or GDP is elastic enough to oil price shocks, the estimated U.S. SPR net benefit is positive. Sensitivity testing around total real costs and benefits range from $380 billion to $80 billion. Limited testing of IEA coordinated drawdowns suggests that total U.S. benefits jump from $122 billion to more than $400 billion putting the SPR strongly in the black. Limited testing of private sector inventory changes was more disappointing and tentatively suggests private activities may at times have offset some of the government drawdowns. With 20-20 hindsight, initial experimentation found that better management could have significantly enhanced the value of the U.S. SPR, especially for the 1990-91 disruption.

Enhancing academic engagement in university students can help enrich students’ educational experience. Drawing on the Conservation of Resources Model and the Job Demand-Resources Model, this study aims to explore the links between undergraduates’ achievement goal orientation and academic engagement (AE), by examining the mediating functions of perceived school climate (PSC) and academic self-efficacy (ASE). Using whole-group sampling, 571 Chinese undergraduates were selected using a self-reporting method to explore the impacts of mastery-approach goals (MAGs) and performance-avoidance goals (PAGs) on AE, as well as the chain mediating effects of PSC and ASE. The findings show that both MAGs and PAGs have a positive, direct, predictive effect on university students’ AE. Additionally, both goal orientations indirectly predict AE through PSC and ASE, separately. The results showed there was also a significant chain mediating effect of PSC and ASE, where for both goal orientations, AE was positively predicted. This study highlights the role of environmental as well as personal factors in facilitating self-regulated learning among university students, and it discusses implications for future research.