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• Describe AN as a multiple weighted network with the CE of HSRN. • Consider the coverage distance of the CE on AN when assessing its robustness. • Investigate the spatial and temporal variations of the CE on AN's robustness. • Investigate the different levels of the CE on AN's robustness. Although previous studies explored the relationship between high-speed rail (HSR) and civil aviation, most of them focus on the negative effects of HSR on civil aviation, including the competition between them. However, studies exploring the positive effects of HSR on civil aviation remain limited. This study demonstrates that a high-speed rail network (HSRN) has a spatiotemporally complementary effect (CE) on the robustness of aviation networks (ANs) against different types of hazards. First, we describe the AN as a multiple weighted network with the CE of HSRN based on the operating routes of flights and trains, instead of an independent network. Then, a novel framework for assessing the robustness of AN is developed considering travel time and service frequency as its metrics and considering the coverage distance of the CE. We find that the CE can obviously reduce the loss of the AN's performance under various disaster scenarios by analyzing the robustness of the AN of Mainland China complemented by HSRN; different levels of CE have different effects on the robustness of AN. Besides the airports located in Eastern China, some non-hub airports such as Changzhou, Wuxi, and Shaorao, are easily complemented by the HSRN. Further, the CE at different times exerts different effects on the robustness of AN, which reach a peak at 16:00 and 07:00. These findings can help broaden the ideas and approaches for enhancing the robustness of the AN. [ABSTRACT FROM AUTHOR]

Massive open online courses (MOOCs) are very popular in China, and it is very important to evaluate and improve them. In this paper, a new evaluation method for MOOCs based on multi‐attribute group decision‐making is proposed. First, an evaluation index system of MOOCs is constructed, which contains six elements and 16 indicators, and multigranular unbalanced hesitant fuzzy linguistic term set (MGUHFLTS) is adopted to describe these indicators. Then based on MGUHFLTS, the aggregation operators are developed, including the multigranularity unbalanced hesitant fuzzy linguistic weighted averaging operator and the multigranularity unbalanced hesitant fuzzy linguistic order weighted averaging operator, moreover, a novel multi‐attributive border approximation area comparison model based on MGUHFLTS is proposed. This model is testified validity and superiority by comparison with other three methods and is applied in evaluation of MOOCs. After ranking five MOOCs, each indicator is analyzed to show how they influenced each element and suggestions are given. [ABSTRACT FROM AUTHOR]

• HSRN is modeled as a two-layer network based on high-speed trains running in it. • Space-time failure effects of high-speed trains on HSRN robustness are investigated. • A method assessing robustness is proposed from function feature and topology feature. • Travel time and passenger flow are taken into account in the methodology. High-speed rail (HSR) has become a critical infrastructure and even has formed a network in some countries, which plays an increasingly significant part in the modern transport system and exerts increasingly obvious impacts on regional economic activity and human mobility. Although its interruption may cause serious consequences, researching its robustness doesn't attract attention until recent years. Based on previous researches on the issue, this paper proposes a comprehensive method to assess the robustness of high-speed rail network (HSRN) by combining the network function features with network topology features and modeling HSRN as a two-layer network based on the high-speed trains running in the network, in which the travel time and passenger flow are taken into account. Finally, taking China's HSRN (CHSRN) as a case study, this paper investigates the failure effects of HSR stations and high-speed trains on the robustness of CHSRN, especially the space-time failure effects of high-speed trains at three typical HSR stations. Results reveal that the failure effects of trains at the selected stations on the performance of CHSRN are limited, and the failure effects of trains at three typical stations on the performance are different as the different failure time, which is beneficial to prioritize the decisions on maintenance resource allocation and prepare emergency response plans. [ABSTRACT FROM AUTHOR]

• A method to assess the vulnerability of PTS comprising subsystem is proposed. • Critical areas of PTS are identified based on running timetable and position data. • Differences of vulnerability or critical area between subsystem and PTS are revealed. • A case of high-speed rail and air transport coupling system in China is researched. The public transport system (PTS) consists of different types of transport subsystems, such as high-speed rail (HSR), air transport (AT), conventional railway, expressway and waterway in a state, which exerts significant impacts on distribution of demographic and economic activities. And its interruption or failure may cause severe social and economic disruption. So the vulnerability analysis of the system attracts an increasing attention. However, most of previous researches mainly concentrate on the vulnerability modeling and analyzing of a single subsystem, neglecting the simultaneous interruption of components, and less considering the complementary effects of other subsystems from systematic perspective and the geographic interdependency among components. For trying to fill these gaps, this paper proposes a method to analyze the vulnerability of PTS composed of two or more transport subsystems and identity the critical area within the system based on the data of running timetable and position coordinates. Finally, taking HSR and AT coupling system in mainland China as a case study, we investigate the differences of vulnerability and critical areas between individual subsystem and overall system. Results reveal that the vulnerability variations and the critical areas distribution of the system are different from these of the subsystems. The research also finds that whether a component is critical depends not only on the system's feature, but also on the component's feature, whether an area is critical depends on economic development and population density of the area. These findings are beneficial to prioritize the plan, budget and maintenance of PTS, and prepare emergency response plans. [ABSTRACT FROM AUTHOR]

Comprehensive risk evaluation of urban areas is important for disaster prevention and mitigation. Since disaster scenarios of urban areas are diverse and complex, the data are generally inadequate for understanding the absolute risk of disaster loss posed by any specific hazard or multi-hazards but adequate for identifying areas that are at relatively higher risk levels to some extent. Therefore, this paper focuses on modeling relative risk assessment for urban disaster loss. Based on disaster system theory, elements at risk and hazard-formative environments were determined as the crucial components to reflect risk discrepancies of different urban areas facing similar hazards. Furthermore, the critical path of interactions between components within the disaster system was constructed by introducing exposure and sensitivity as filtering processes. On this basis, a relative risk model for urban disaster loss assessment was constructed and applied to cities in Liaoning Province as an illustration. In addition, the results were represented and analyzed from multi-dimensions. A test for the uncertainties of the results indicates that this model shows a strong applicability for urban disaster loss relative risk assessment on the premise of accurate data concerning elements at risk and hazard-formative environments. [ABSTRACT FROM AUTHOR]

Regional human exposure to the hazard is an important basis of decision support for more efficient and effective emergency management especially pre-event. Due to the diverse locations of human activities and the displacements they induce, the spatial distribution of population is inhomogeneous and strongly time-dependent. Hence, in the present work, land use pattern was introduced to reflect the distribution characteristics of human exposure in hazard affected regions both in daytime and nighttime. Human activities that contribute to spatial distribution variance were considered to establish the correlation between human types and land-use patterns at a regional scale. Furthermore, hypergraph was used to model the regional human exposure in order to benefit the analysis of spatial–temporal distribution characteristics of population, and variance algorithms for disaggregating different styles of human to the regional land were constructed. What’s more, the model was applied to the analysis of potential human exposure in the built district of Dalian City. Results show that a great amount of area and population are beyond moderate exposure levels on urban construction land of Dalian City, and the population potentially exposed significantly increases from nighttime to daytime periods, especially in the zones with diverse human activities. The presented approach in this study can not only be of utmost importance for vulnerability assessment or risk evaluation, but also for regional and environmental planning as well as local development. [ABSTRACT FROM AUTHOR]

The contamination status of novel organophosphate esters (NOPEs) and their precursors organophosphite antioxidants (OPAs) and hydroxylated/diester transformation products (OH-OPEs/di-OPEs) in soils across a large-scale area in China were investigated. The total concentrations of the three test NOPEs in soil were 82.4-716 ng g -1 , which were considerably higher than those of traditional OPEs (4.50-430 ng g -1 ), OPAs (n.d.-30.8 ng g -1 ), OH-OPEs (n.d.-0.49 ng g -1 ), and di-OPEs (0.57-21.1 ng g -1 ). One NOPE compound, i.e., tris(2,4-di- tert -butylphenyl) phosphate (AO168 = O) contributed over 65% of the concentrations of the studied OPE-associated contaminants. A 30-day soil incubation experiment was performed to confirm the influence of AO168 = O on soil bacterial communities. Specific genera belonging to Proteobacteria, such as Lysobacter and Ensifer , were enriched in AO168 = O-contaminated soils. Moreover, the ecological function of methylotrophy was observed to be significantly enhanced ( t -test, p < 0.01) in soil treated with AO168 = O, while nitrogen fixation was significantly inhibited ( t -test, p < 0.01). These findings comprehensively revealed the contamination status of OPE-associated contaminants in the soil environment and provided the first evidence of the effects of NOPEs on soil microbial communities.