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Proton exchange membrane fuel cell (PEMFC) is significant and favorable to the long-range and short refueling time in the vehicle industry. However, the non-uniform distribution of gas flow supply, particularly in the fuel cell stack is neglected in the electrochemical model for PEMFC performance optimization. The purpose of this study is to break through this limitation to establish an optimized electrochemical fuel cell performance model, with porous media methods considering the non-uniform gas flow distribution in fuel cell stack with different compression of the gas distribution layer (GDL). The numerical models are validated by experimentation of a practical fuel cell stack. For the established fuel cell model, there is a 5% difference between the maximum and minimum speeds of various flow channels in the anode flow field under 10% GDL compression. Furthermore, the single-channel electrochemical performance model is optimized by considering the non-uniform gas flow distribution of the fuel cell stack. The results of the optimized electrochemical fuel cell performance model demonstrate that the correlation coefficient between the experiment results and the simulation results is nearly 99.50%, which is higher than that of the original model under 20% GDL compression. This established model is effective in enhancing the prediction accuracy of the PEMFC performance. [ABSTRACT FROM AUTHOR]

The transition analysis and type division of landscape heritage are the effective management methods to achieve the overall conservation and targeted utilization of modern urban parks. In this study, Shenyang Zhongshan Park, the first modern urban park in Shenyang, was taken as the research object to explore the historical and cultural value of modern urban parks in Northeast China. The current status and transition characteristics of landscape heritage were analyzed, and the landscape heritage types were divided by their conservation and utilization evaluations. A total of 44 landscape heritages existed in Shenyang Zhongshan Park, including three categories, i.e., 15 historic sites, 20 cultural comprehensive sites, and 9 natural sites. Based on the IPA model, the landscape heritage was further divided into three subcategories, i.e., already designated for conservation (ADC), should be designated for conservation (SDC), and should be restricted scale (SRS). ADC was composed of one historic (Chiyoda water tower), two cultural comprehensive (water sources), and three natural (ancient trees) landscape heritages. SDC was a landscape heritage with long construction age, high importance, poor conservation, and high utilization, which can represent the cultural characteristics of the park and the need to speed up the improvement of its protection system. SRS weakened the cultural characteristics of the park. Its construction intensity should be reduced to highlight the core themes of the park (i.e., historical and cultural themes). In the future, modern urban parks should be conserved and utilized based on identifying different landscape heritage types. This study provides a theoretical basis for the management and development of modern urban parks from the perspective of conservation and utilization of landscape heritage. [ABSTRACT FROM AUTHOR]

Increasing concentrations of atmospheric particulate matter (PM) can cause a serious threat to urban air quality and human health. To reduce PM pollution in urban environments, pragmatic screening and planting of tolerant tree species can be effective and sustainable ways. However, our understanding of the effects of the capture ability of PM2.5 on plant tolerance, and efforts to devise explicit assessment tools for suitability analysis for urban green belt plantations, are still inadequate. In this study, six common green tree species (Pinus tabuliformis, Abies holophylla, Juniperus chinensis, Salix babylonica, Robinia pseudoacacia, and Populus alba) from three pollution sites in Shenyang City, China, were collected in order to assess their PM2.5 capture ability, biochemical characteristics, leaf microstructures, and air pollution tolerance index (APTI). The results revealed that different sites and tested plant species can significantly affect the amount of PM2.5 retained by leaf surfaces. The PM2.5 retention amount of Abies holophylla was the highest at the SFH site and 1.41–8.89 times that of other tested species (p < 0.05). Morphological plant attributes, such as leaf surface roughness (r = 0.52 **) and contact angle (r = −0.57 **), were strongly related to the PM2.5 retention amount. The PM2.5 retention amount per unit leaf area had the strongest and most significant negative influence on total chlorophyll content (r = −0.743 **), indicating that the accumulation of leaf PM2.5 reduced the photosynthetic efficiency of the plants. Among the tested plants, Robinia pseudoacacia had the highest APTI value and was identified as the most resilient plant at all three sites, whereas Juniperus chinensis had the lowest APTI at all study sites. However, the integration of PM2.5 capture ability with APTI showed Pinus tabuliformis to be the best species for the construction of urban green belts in Shenyang City. [ABSTRACT FROM AUTHOR]

In order to study the physical and mechanical properties of sandstone under high-temperature water-cooling cycling conditions, an RMT-150B electrohydraulic servo rock testing system and a DS-5 acoustic emission detection and analysis system were used to conduct uniaxial compression acoustic emission tests on sandstone after high-temperature water-cooling cycles. The deformation, strength, and acoustic emission characteristics of sandstone were analyzed under different temperatures and cycle times. The results show that the high-temperature water-cooling effect caused changes in the physical properties of sandstone. The volumetric expansion rate of the rock samples first decreased, then increased in temperature, and the strength first increased, then decreased, whereas the number of cycles had less of an impact on the physical properties. At 200 °C, with increased cycle number, the elastic modulus increased by 20.1%, and the compressive strength increased from 63.9 MPa to 71.46 MPa. At 300–600 °C, the elastic modulus and compressive strength of sandstone gradually decreased with increases in the temperature and cycle number, with reductions of 6.04%, 7.24%, 28.7%, 35.57%, 17.6%, 18.2%, 20.4%, and 60.5%, respectively. With increased temperature and cycle times, the acoustic emission ringing counts increased, ringing counts and cumulative energy appeared earlier, the rock samples entered elastic deformation earlier, the yield stage length increased, and the samples showed a tendency to transition from brittle to ductile damage. [ABSTRACT FROM AUTHOR]

Given the escalating issue of climate change, environmental protection is of growing importance. A rising proportion of battery-powered scooters are becoming available. However, their range is limited, and they require a long charging time. The fuel cell–battery-powered electric scooter appears to be a promising alternative. Further development of the active hybrid is the passive hybrid, in which the fuel cell is directly coupled to the battery, eliminating the need for a DC/DC converter. The passive hybrid promises the possibility of a reduction in the installation volume and cost. A simulation model is created MATLAB/Simulink for the passive fuel cell–battery hybrid electric scooter. It specifically focuses on how the power split between the fuel cell and battery occurs under dynamic load requirements. The scooter is powered by two air–hydrogen Proton Exchange Membrane Fuel Cell (PEMFC) systems with a nominal power of 250 W each and a Li-ion battery (48 V, 12 Ah). The validation is performed following an ECE-R47 driving cycle. The maximum relative deviation of the fuel cell is 2.82% for the current value. The results of the simulation show a high level of agreement with the test data. This study provides a method allowing for an efficient assessment of the passive fuel cell–battery hybrid electric scooter. [ABSTRACT FROM AUTHOR]

PEMFCs (Proton Exchange Membrane Fuel Cells) are commonly used in fuel cell vehicles, which facilitates energy conversation and environmental protection. The fuel cell electrochemical performance is significantly affected by the contact resistance and the GDL (Gas Diffusion Layer) porosity due to ohmic and concentration losses. However, it is difficult to obtain the exact performance prediction of the electrochemical reaction for a fuel cell design, resulting from the complex operating conditions of fuel cells coupled with the assembly force, operating temperature, relative humidity, etc. Considering the compression behavior of porosity and the contact pressure in GDLs, a force-temperature-humidity multi-field coupled model is established based on FEA (Finite Element Analysis) and CFD (Computational Fluid Dynamics) for the fuel cell electrochemical performance. Aside from that, the characteristics between the contact resistance and the contact pressure are measured and fitted through the experiments in this study. Finally, the numerical model is validated by the experiment of the fuel cell stack, and the error rate between the presented model and the experimentation of the full-dimensional stack being a maximum of 3.37%. This work provides important insight into the force-temperature-humidity coupled action as less empirical testing is required to identify the high fuel cell performance and optimize the fuel cell parameters in a full-dimensional fuel cell stack. [ABSTRACT FROM AUTHOR]

Health is the basis of human survival and development. It is not only related to quality of life but also guarantees national security and social stability. Under the combined influence of various factors, large regional differences exist with regard to the health levels of residents in the Yellow River Basin (YRB). Here, we took 73 prefecture-level cities (leagues and prefectures) in the YRB as our research object. We constructed an index system and a measurement model and applied geographical information system (GIS) technology and quantitative analysis methods to make comprehensive spatial and temporal measurements of the health index of residents in the YRB and further analyzed the influencing factors. Overall, the health index of residents in the YRB showed a steady upward trend. However, some differences exist across various regions with regard to residents' health index. The YRB resident health index displayed positive spatial autocorrelation; spatial clustering showed an initial decrease, followed by an increase, suggesting notable fluctuations. With the increase in per capita GDP, urbanization rate, and household size, the health index of residents in the YRB has improved. However, increased wastewater and waste gas discharge has led to a decrease in the health index of residents in the YRB. [ABSTRACT FROM AUTHOR]

Air pollution is a pressing issue that poses significant threats to human health and the ecological environment. The accurate prediction of air quality is crucial to enable management authorities and vulnerable populations to take measures to minimize their exposure to hazardous pollutants. Although many methods have been developed to predict air quality data, the spatio-temporal correlation of air quality data is complex and nonstationary, which makes air quality prediction still challenging. To address this, we propose a novel spatio-temporal neural network, GCNInformer, that combines the graph convolution network with Informer to predict air quality data. GCNInformer incorporates information about the spatial correlations among different monitoring sites through GCN layers and acquires both short-term and long-term temporal information in air quality data through Informer layers. Moreover, GCNInformer uses MLP layers to learn low-dimensional representations from meteorological and air quality data. These designs give GCNInformer the ability to capture the complex and nonstationary relationships between air pollutants and their surrounding environment, allowing for more accurate predictions. The experimental results demonstrate that GCNInformer outperforms other methods in predicting both short-term and long-term air quality data. Thus, the use of GCNInformer can provide useful information for air pollutant prevention and management, which can greatly improve public health by alerting individuals and communities to potential air quality hazards. [ABSTRACT FROM AUTHOR]

Building atrium design is crucial to maintaining a sustainable built environment and providing thermal comfort to occupants. This study proposes a parametric framework to optimize the atrium's geometry for environmental performance and thermal comfort improvement. It integrates the parametric design, performance simulation, and multi-objective optimization in the Rhino and Grasshopper platform to realize automatic optimization. The atrium's well index, shape ratio, volume ratio, position index, and inner interface window-to-wall ratio were set as optimized factors. For the optimization objectives, useful daylight illuminance (UDI), energy use intensity (EUI), and the discomfort time percentage (DTP) were chosen as metrics for the measurement of daylighting, energy use efficiency, and thermal comfort, respectively. Moreover, a geometry mapping method is developed; it can turn atrium shape into rectangular profiles. Thus, the framework can apply to general buildings. To validate the effectiveness of the proposed framework, an atrium optimization case study is conducted for a villa in Poland. According to the optimization results, the performance of the compared three objectives are improved by 43.20%, 15.52%, and 3.89%, respectively. The running time for the optimization is about 36 s per solution, which greatly reduce the human and time cost compared to the traditional working method. [ABSTRACT FROM AUTHOR]

The quest for carbon neutrality raises challenges in most sectors. In coal mining, overcapacity cutting is the major concern at this time, and the increase in the number of abandoned mine shafts is a pervasive issue. Pumped storage hydropower (PSH) plants built in abandoned mine shafts can convert intermittent electricity into useful energy. However, studies on basic theories and key technologies are a pressing issue. Six key scientific problems have been identified in PSH development in abandoned mine shafts that are relevant to China's national conditions, current resource structure, and relative status of energy storage technologies in China and other countries. It is proposed that the research on pumped storage should move closer to the direction of intelligence, stabilization, and greening, and the construction and development should gradually realize integration, completion, and coordination. The goal is to realize integrated, complete, and coordinated development of PSH in abandoned mine shafts, streamline national policies concerning PSH, drive the co-development of industry, education and research, and achieve the carbon neutrality targets set by China. [ABSTRACT FROM AUTHOR]

A set of Belleville springs integrated into an endplate plays a key role in a proton exchange membrane fuel cell (PEMFC) stack, which makes the applied assembly force smoother, resulting from the absorbed vibration and thermal expansion. The appropriate arrangement of Belleville springs is important in PEMFC stack design. The aim of this study is to establish an equivalent beam model to optimize the numbers and positions of Belleville springs to minimize endplate deformation. Based on this, a finite element analysis (FEA) model of the PEMFC stack is proposed to further optimize the cross-sectional shape of the endplate. For the endplate with two, three and four groups of Belleville springs, its optimal positions correspond to 0.17 l in , 0.27 l in and 0.5 l in (lin is the equal distance between steel belts). In addition, the low thickness should be 2/3 of the high thickness of the curved endplate for a uniform contact pressure distribution as well as the high-volume-specific power. However, the curvature radius of the endplate arc is negative to the uniformity of the contact pressure distribution, and particularly the internal cells of the PEMFC stack. This study provides a design direction for endplates combined with Belleville springs in large fuel cell stacks clamped with steel belts. [ABSTRACT FROM AUTHOR]

High-performance proton exchange membrane fuel cell (PEMFC) vehicles are important for realizing carbon neutrality in transportation. However, the optimal power density of the fuel cell performance is difficult to achieve due to the internal complex operating conditions of a fuel cell stack. Moreover, there is a lack of effective models to solve the coupled multi-physical fields (force, temperature and humidity, etc.) in the PEMFC, particularly considering the gas diffusion layer (GDL) compression. Thus, a force-temperature-humidity coupled modeling method is introduced to evaluate the effects of key operating conditions for the fuel cell performance parameter matching. Firstly, the interfacial contact resistance and GDL porosity are obtained by a force-temperature coupled simulation using a finite element analysis (FEA) modeling, then the obtained results are introduced into a temperature-humidity coupled simulation using a computational fluid dynamics (CFD) modeling. An iteration algorithm is proposed to realize the force-temperature-humidity coupled simulation for the PEMFC performance. The main characteristics of the PEMFC performance parameters are revealed and the optimum matching criteria of the main performance parameters (temperature, stoichiometric ratio and relative humidity) are determined. The presented co-simulation method is significant and effective for realizing the PEMFC performance parameter matching condition, and it provides a design direction for an optimal power density of a fuel cell stack. [ABSTRACT FROM AUTHOR]

As effective filters for natural particulate matter (PM), plants play an important role in the reduction of PM, thus improving air quality. However, research on the relationship between leaf functional traits and PM retention capacity in different polluted environments remains limited. In this study, six tree species (Abies holophylla, Pinus tabuliformis, Juniperus chinensis, Populus berolinensis, Salix babylonica, Robinia pseudoacacia) in Shenyang city, China were selected as research objects to analyze their PM retention capacity in three different polluted environments (i.e., a busy road, an industrial area of the urban center, and a green space). Additionally, we determined the composition of trace elements associated with the different polluted environments; we also evaluated the impact of different polluted environments on leaf surface traits. The results showed that the actual amounts of PM and trace elements that accumulated on leaf surfaces differed considerably between pollution sites and plant species. The greatest accumulation of PM10 and PM2.5 deposited on the leaves of tested plants was at a traffic-related pollution site and the smallest accumulation was at a park site. There were significant differences in the PM10 and PM2.5 retention capacities of leaves among the different tree species (p < 0.05), in the following order: Abies holophylla > Pinus tabuliformis > Juniperus chinensis > Populus berolinensis > Salix babylonica > Robinia pseudoacacia. The average PM10 and PM2.5 accumulation amounts of Abies holophylla were 1.28–8.74 times higher than these of the other plants (p < 0.05). Trace element analysis showed that the elemental composition of PM accumulated on leaf surfaces was location-dependent. In conclusion, a highly polluted environment can increase the average groove width, stomatal density, and roughness compared to a low-polluted environment. In contrast, the average value of contact angle is higher at low-pollution sites than at other sites. These results suggest that Abies holophylla is the most suitable greening tree species and that its widespread use could significantly reduce PM pollution in urban environments. [ABSTRACT FROM AUTHOR]

The deflection of the endplate under the clamping force has a vital effect on fuel cell performance. An optimal cross-sectional shape with a high moment of inertia of the endplate is significant to maximize the bending stiffness of the fuel cell stack. Five cross-sectional shapes (rectangular, round, parabolic, rectangular + round, and rectangular + parabolic) of the typical endplates are proposed. An analytical study on the moments of inertia of the endplates is introduced and analyzed. The maximum moments of inertia of the cross-sections are obtained and displayed in a matrix in thickness and length. The statistical results show that the "rectangular + parabolic" cross-section has the advantage of wide dimensional size while maintaining a high moment of inertia. Finally, the analytical studies are validated by a finite element method (FEM) and the corresponding trends are highly agreed upon. The maximum moment of inertia of the parabolic endplate is 85.71% higher than the rectangular endplate with a thickness of 80 mm, and the corresponding contact pressure variance is 6.15% less than the rectangular endplate. The presented analytical study is significant and effective to optimize the cross-sectional shape of the endplate and provide an endplate design direction for a large fuel cell stack. [ABSTRACT FROM AUTHOR]

The transformation of old neighborhoods involves many important types of livelihood development projects, of which smart transformation is considered one of the most important tasks at present. The smart transformation of old neighborhoods provides an important means to promote sustainable development; however, enhancing the willingness of residents to participate is an important prerequisite for the smart transformation of old neighborhoods. Considering perceptive value acceptance theory and community ownership theory in the field of information management and sociology, we study the intention of residents in old communities to participate in intelligent transformation and its influence mechanisms. Our results show that willingness to participate in the smart renovation of old residential areas is positively affected by the perceived value of smart renovation and the sense of community attachment of residents. The sense of community plays an intermediary role in the relationship between perceived value and willingness to participate in smart renovation. At the same time, the perceived value of intelligent renovation of old residential areas and a sense of community have chain mediating effects between perceived usefulness, perceived enjoyment, perceived risk, perceived cost, and willingness to participate. This paper not only achieves theoretical expansion but also provides good support for accelerating the intelligent transformation of old communities in China. [ABSTRACT FROM AUTHOR]

High-power proton exchange membrane (PEM) fuel cell vehicles are important for the realization of carbon neutrality in transportation. However, it is difficult to maintain enough fuel supply and quick water removal capacity at a high current density where reactant gas transportation and water concentration are directly affected by flow channel configurations. This study aims to investigate the tapered slope effects of a flow channel on fuel cell performance using a 3-D CFD model. The positive, negative, zero and hybrid tapered slopes are proposed to illustrate the fuel cell voltage, reactant gas and water vapor concentration in the flow channels. Among them, the flow channel with a positive tapered slope performs better, especially at a high current density. Then, the positive tapered slope effects are discussed, including different tapered slopes, inlet depths and widths of flow channels. The results show that the larger the tapered slope, the smaller the depth and width, and the better the fuel cell performs; the corresponding current densities are increased by a maximum of 6.53%, 12.72% and 61.13%. The outcomes stated above provide a key direction for flow channel design that can particularly achieve higher fuel cell power density at high current densities. [ABSTRACT FROM AUTHOR]

To feed the growing human population, natural grasslands are being converted to agricultural use at a massive scale. This conversion may have consequences for soil biodiversity, but its impact on the community assembly of differentially microbial groups remains largely unknown. Here, we selected the three typical land-use types: grassland, arable land (formerly grassland), and forest (formerly grassland) in the Songnen Plain, Northeastern China. Illumina MiSeq high-throughput sequencing technology based on bacterial 16S rRNA and fungal ITS rRNA was used to study the community structures and diversities of soil bacteria and fungi and to explore the drivers of these changes. The results showed that bacterial community diversity did not change after grassland conversion to forest and arable land, but affected bacterial community abundance at the phylum level. Actinomycetes and Proteobacteria were significantly reduced, Acidobacteria were significantly increased, and Gemmatimonadetes and Bacteroidetes were the most abundant in arable land. Land conversion had significant effects on both fungal community diversity and abundance. After the grassland was converted into forest, the fungal community diversity decreased, but the community abundance increased significantly, the Ascomycetes decreased significantly, and Basidiomycetes became the dominant phylum, especially white rot fungi. Interestingly, the fungal community diversity and community abundance increased significantly after grassland was converted to arable land, and the abundance of Zygomycota increased significantly but the dominant phylum was still Ascomycetes. Canonical correlation analysis (CCA) showed pH, MC, NO3−-N, TP, AP, and other soil factors are important factors affecting the composition of microbial communities. In the soil of this study area, the composition of bacterial communities is mainly driven by changes in pH and soil texture, and the composition of fungal communities is most closely related to changes in soil nutrient utilization. Changes in land-use patterns have an effect on the structure and diversity of microbial communities by changing the physical and chemical properties of the soil. [ABSTRACT FROM AUTHOR]

The contact pressure between bipolar plates (BPPs) and a membrane electrode assembly (MEA) has a key impact on Proton Exchange Membrane Fuel Cell (PEMFC) performance. However, it is difficult to obtain the contact pressure combined with operating temperature action via the finite element analysis (FEA) model, resulting in limited calculation resources for the problem of multiscale and thermo-mechanical coupled action in a full-dimensional fuel cell stack. This paper establishes an equivalent stiffness model for contact pressure, which could be predicted simply and quickly compared with the FEA model. Then, this presented model is validated by experimentation with a full-dimensional fuel cell stack assembled with 10 cells using pressure-sensitive film. The error between the presented model and the experimentation of the full-dimensional stack is a maximum of 4.41%. This work provides important insight into thermo-mechanical coupled action, as less empirical testing is required to identify the contact pressure in a full-dimensional fuel cell stack. [ABSTRACT FROM AUTHOR]

The endplate plays an important role in the performance and durability of fuel cell stacks, and also to mass power density. Aiming at a lightweight endplate and uniform deflection of the endplate, the purpose of this study is to model the endplate including the supply, discharge ports and the distribution manifolds. The stress and displacement distribution of the endplate are also analyzed by numerical simulation. After that, the three optimized topologies aiming to minimize compliance, uniform stress distribution and two objectives coupling are discussed, and the intake endplate and blind endplate are individually reconstructed. The mass of optimized intake endplate is reduced by 35%, and the mass of optimized blind endplate is reduced by 46% for the goal of attaining a lightweight endplate, while maintaining the uniformity of the stress distribution of the first cell next to the endplate. Considering these factors, optimized endplates are obtained, which are valuable to fuel cell stack design. [ABSTRACT FROM AUTHOR]

Studies on land use structural optimization can support the sustainability of land resources. The Taipusi Banner lies in the arid and semiarid area of northern China, with rapid economic development and a vulnerable ecological condition. Taking the Taipusi Banner as a research case, we adopted a land use map and statistical data, and employed the ecosystem process model to establish five scenarios, including an economically optimal scenario, an ecologically optimal scenario, a comprehensively optimal scenario, a status quo, and a projected scenario. Based on multi-objective linear programming, the land use demand was optimized; then, the CLUE-S model and adaptability evaluation were adopted to establish spatial patterns. The ecological and economic benefits were then analyzed and policy suggestions are provided. The main results include the following: (1) The optimization outputs of various scenarios show that under optimization, cropland and forestland increased by 9.13% and 18.9%, respectively, and grassland decreased by 9.81%. (2) The land use optimization shows that comprehensive optimization aimed at achieving comprehensive benefits, ecological benefits, and economic benefits increased these benefits by 3.89%, 2.1%, and 6.2%, respectively. Compared with other scenarios, focusing on the comprehensive benefits of land use can result in the greatest increase in benefits to improve sustainability land resources. Land use optimization must consider not only the optimization of both the quantity and configuration but also the dimensions of both ecology and the economy. Land use should be based on a land suitability evaluation and optimization of the land use spatial configuration to update ineffective land uses and should gradually adjust both the ecological and engineering measures. [ABSTRACT FROM AUTHOR]

Consumers are increasingly concerned about food quality. The "Same line Same standard Same quality" (Santong) program has been implemented to improve food quality in the Chinese domestic market. The Santong program means that exporters are encouraged to produce goods on the same production line, following the same standards and the same quality requirements for both the export target market and the domestic market. Using data collected from an online choice experiment on tomatoes, we examine Chinese consumer preferences and their willingness to pay (WTP) for the Santong claim, export target market quality and organic certification. Three types of export target market, indicating different technical regulations and standards, are considered. Our results show that consumers are willing to pay for the Santong quality claim and for export goods with a target market of "EU". Furthermore, we also identify the substitution effects between the Santong claim and organic certification. The results of our study provide solutions for both Chinese exporters and the Chinese government to meet the need for a high level of food quality accompanied by domestic consumption upgrade, and achieve the transformation from export to domestic sales. Our results may also provide solutions for other emerging economies, where governments raise the level of food quality in domestic markets and support the domestic sales of exporters after the shock of the coronavirus (COVID-19) pandemic in 2019. [ABSTRACT FROM AUTHOR]

Education for sustainable development is an evolving concept aimed at providing an understanding of the relationship between sustainable development issues and the development of knowledge, skills, perspectives and values, which will enable people of all ages to commit themselves to creating a sustainable future. The aim of the study is the development of a widely applicable model of e-learning, which consists of seven consecutive levels of professional and personal development and is conceptually associated with a self-regulation strategy. The methodological core of such model creation is the theory of niche construction. Its application to the understanding of the systemic educational process allowed the assumption that, under the evolutionary pressure of the educational environment, a person is engaged in self-learning and self-development processes. Thus, needing to adapt to the educational niche's interaction, the individual affects its development through active inclusion in the training process, showing a personal evolutionary impulse. The system, in turn, affects one's individual growth through the socialization of his/her personal and professional qualities. The scientific novelty of this article lies in the proposed widely applicable, presumably universal model of distance education, which consists of seven levels of professional development. The results show progress in students' mastery of skills, which are an integral part of education for sustainable development (ESD), namely, foresight, critical thinking and reflection, systemic thinking, building partnerships, and participating in decision-making. This article also demonstrates the existing functionality of platforms that technologically support the educational process, indicates their strengths and defines areas for further improvement and development within the framework regarding the concept of education for sustainable development. The study outcomes confirm the effectiveness of a universal distance education model for the stable professional growth of tourism and hospitality staff. Thus, it is advisable to implement the model's conceptual structure into educational programs of modern e-learning systems. Supposed universality of the model opens up the possibility of its use in almost all fields for training personnel. [ABSTRACT FROM AUTHOR]

Trust as a form of social capital plays an important role in improving the cooperation between agents, especially in credit lending activities. Trust building has attracted significant research interest, and gift giving has been shown to be one of its main drivers. Nonetheless, the mechanism of gift giving in the formation of trust networks and the channels through which gift giving and trust affect cooperation require further investigation. In this paper, we first separate social trust into community trust and personal trust, and we examine how gift giving affects the formation of each level of trust. We then explore how trust and gift giving affect rural households' access to formal and informal sources of credit. Our results show that gift giving mainly helps in forming trust at the personal level rather than the community level. In turn, personal and community trust can facilitate access to informal and formal sources of credit, respectively. In addition, personal trust facilitates access to informal loans for consumption and medical expenses but not production. Overall, our findings show that gift giving is mainly used to build personal trust which facilitates access to informal lending for risk-sharing purposes. [ABSTRACT FROM AUTHOR]

The global background of energy shortages and climate deterioration demands bioclimatic sustainable buildings. Vernacular architecture can provide a useful resource of passive strategies and techniques for creating inner comfort conditions with minimum heating, ventilation, and air conditioning (HVAC) assistance. The identification and verification of such knowledge are essential for climate responsive or energy passive building design. Among the methods, computational fluid dynamics (CFD) is a useful tool for simulating convective heat transfer of vernacular architecture and predicting the convective heat transfer coefficient (CHTC) and flow field. Geometric complexity and diversity of building samples are crucial in the development of an effective simulation methodology in terms of computational cost and accuracy. Therefore, this paper presents high-resolution 3D steady Reynolds-averaged Navier–Stokes (RANS) CFD simulations of convective heat transfer on Japanese vernacular architecture, namely, "machiya." A CFD validation study on the CHTC is performed based on wind-tunnel experiments on a cube heated by constant heat flux and placed in a turbulent channel flow with a Reynolds number of 3.3 × 104. Three steady RANS models and two boundary layer modeling approaches are compared and discussed. Results show that the SST k-ω model applied with low Reynolds number modeling approach is suitable for CHTC simulations on a simplified building model. The RNG k-ε model applied with wall functions is an appropriate choice for simulating flow field of a complicated building model. Overall, this study develops a methodology involving RANS model selection, boundary layer modeling, and target model fitting to predict the convective heat transfer on vernacular architecture. [ABSTRACT FROM AUTHOR]

Commercial banks follow sustainable development strategies to provide green credit for companies. As the main target for banks to issue green credit, environmental protection companies carry out research and development (R&D) activities for the purposes of protecting the environment and sustainable development. Therefore, the R&D level of environmental protection companies is a measure of whether the green credit policy meets its purpose. Therefore, it is particularly important to study green credit from a company perspective. This paper used panel data from 24 environmental protection companies listed on the Shanghai and Shenzhen Stock Exchange from 2012 to 2017 and adopted a threshold model to examine the relationship between green credit and company R&D level. The results indicate that there is a positive but nonlinear relationship between green credit and company R&D levels. The empirical analysis through the threshold model shows that a threshold effect remains on the relationship and this threshold effect is caused by the levels of firm size, bank lending, and government subsidies. [ABSTRACT FROM AUTHOR]

Focusing on the multi-depot vehicle routing problem (MDVRP) for hazardous materials transportation, this paper presents a multi-objective optimization model to minimize total transportation energy consumption and transportation risk. A two-stage method (TSM) and hybrid multi-objective genetic algorithm (HMOGA) are then developed to solve the model. The TSM is used to find the set of customer points served by each depot through the global search clustering method considering transportation energy consumption, transportation risk, and depot capacity in the first stage, and to determine the service order of customer points to each depot by using a multi-objective genetic algorithm with the banker method to seek dominant individuals and gather distance to keep evolving the population distribution in the second stage, while with the HMOGA, customer points serviced by the depot and the serviced orders are optimized simultaneously. Finally, by experimenting on two cases with three depots and 20 customer points, the results show that both methods can obtain a Pareto solution set, and the hybrid multi-objective genetic algorithm is able to find better vehicle routes in the whole transportation network. Compared with distance as the optimization objective, when energy consumption is the optimization objective, although distance is slightly increased, the number of vehicles and energy consumption are effectively reduced. [ABSTRACT FROM AUTHOR]

The cultural attributes of architecture in touristic cities are vital to city image building, city branding, and rebranding, as well as generating more economic profits for sustainable urban development, and protecting cultural sustainability. However, many studies on this theme focus on the singularity of architecture referring to its stylistic or morphological definitions, lacking attention to visitors’ cultural experiences in the architectures. Considering the importance of personal experience involved in cultural activities as a process of spatial narration through which architecture makes sense to visitors and generates cultural values, the aim of this paper is to reveal the respective correlations between different types of architecture regarding the cultural experience it imparts and the non-positive dimensions of the city image. This research builds a categorization system of three cultural types of architecture, and designs a questionnaire to collect tourists’ personal opinions concerning architectures and the city image of Amsterdam’s waterfront in order to calculate such correlations statistically. The results associate architectures with ‘tourism-oriented’, ‘present/process-based’, and ‘mass’ cultural types with non-positive dimensions of city image, which leads to further discussions of ‘authenticity’, ‘identity’, and ‘mass culture’, suggesting the significance of urban cultural policies and local communities in terms of city rebranding. [ABSTRACT FROM AUTHOR]

For a long time, governments and enterprises have been the two main subjects for environmental governance in China. With the growing complexities of environmental issues and the improvement of public environmental awareness, public participation is gradually playing an important role in the process of China’s environmental governance. This paper aims to explore the necessity, the rationale, and the specific effect of public participation on environmental governance in China. A theoretical model is first proposed to illustrate the significance of public participation. Then, an empirical model is built to investigate the impact of public participation on pollutant emissions of the four main pollutants SO2, NOx, COD, and NH4, based on the panel data of 30 provinces from 2011 to 2015 in China. The results and main findings are: (1) public environmental complaints exert a noticeable and positive impact on the reductions of pollutants; (2) this impact varies according to different pollutants, among which reducing SO2 emissions shows the most efficiency; and (3) the impact of public participation on the reduction of pollutants shows the characteristics of hysteresis and regional difference. We find that when the rate of public participation of lagging one period increases by 1%, the reduction of SO2 is 5.03 tons per capita, 1.54 tons per capita, and 0.94 tons per capita in the region of middle, east, and west China, respectively. Therefore, the status of public participation should be strengthened and effective public participation is urgently needed in environmental governance. A systematic cooperative governance among the public, governments, and enterprises needs to be established in the long run. [ABSTRACT FROM AUTHOR]