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This paper investigates the structural performance of novel steel-plate concrete containment structures, focusing on third-generation nuclear power plants. To address the challenges of increased complexities and costs associated with double-layer containment designs, this study explores the potential of steel-plate concrete structures to enhance safety, economic efficiency, and construction simplicity. The steel-plate concrete structure, characterized by its core concrete and dual steel plates, shows superior compressive strength, bending resistance, and elastoplasticity. Extensive numerical analyses, including finite element modeling and thermal-stress coupling, were conducted under various load conditions. Under structural integrity test conditions, the maximum radial displacement observed was 24.59 mm. Under design basis conditions, the maximum radial displacement was 47.61 mm; under severe accident conditions, it was 53.83 mm. The ultimate bearing capacity was 0.91 MPa, 2.17 times the design pressure. This study concludes that the steel-plate concrete containment structure maintains a high safety margin under all tested conditions, with stress and strain well within acceptable limits. It can effectively serve as a robust barrier against radioactive leakage and malicious impacts, providing a viable alternative to conventional containment designs. [ABSTRACT FROM AUTHOR]

A prestressed concrete containment is the enclosure structure of a nuclear reactor that serves as the last physical barrier of a nuclear power plant (NPP) safety defense system. It plays a key role in the prestress time-limited aging analysis (TLAA) required for operating license extensions for NPPs. Considering prestress containment systems without long-term monitoring tendons in a nuclear power plant, the technical route for prestress TLAAs involves analyzing operating license extension regulations and in-service monitoring technical requirements for prestressed tendons performance. Using tendons based on theoretical calculations of prestress loss in a nuclear power plant and the minimum required value of prestress determined by numerical simulation, the theoretical predictive value can be compared with the minimum required value for prestressed steel tendons. This comparison can be used to evaluate the 20-year life extension of the prestress system and provide a reference for aging and life management of NPPs. [ABSTRACT FROM AUTHOR]

Abstract: Studies on volunteered geographic information (VGI) have focused on examining its validity to reveal geographic phenomena in relatively recent periods. Empirical evaluation of the validity of VGI to reveal geographic phenomena in historical periods (e.g., decades ago) is lacking, although such evaluation is desirable for assessing the possibility of broadening the temporal scope of VGI applications. This article presents an evaluation of the validity of VGI to reveal historical geographic phenomena through a citizen data‐based habitat suitability mapping case study. Citizen data (i.e., sightings) of the black‐and‐white snub‐nosed monkey (Rhinopithecus bieti) were elicited from local residents through three‐dimensional (3D) geovisualization interviews in Yunnan, China. The validity of the elicited sightings to reveal the historical R. bieti distribution was evaluated through habitat suitability mapping using the citizen data in historical periods. The results of controlled experiments demonstrated that suitability maps predicted using the historical citizen data had a consistent spatial pattern (correlation above 0.60) that reflects the R. bieti distribution (Boyce index around 0.90) in areas free of significant environmental change across historical periods. This in turn suggests that citizen data have validity for mapping historical geographic phenomena. It provides supporting empirical evidence for potentially broadening the temporal scope of VGI applications. [ABSTRACT FROM AUTHOR]

Numerous restoration programs have been launched worldwide in recent years, but the effectiveness of such programs for biodiversity conservation remains unclear. Additionally, priority areas of restoration need to be identified in a region where resources are limited. Habitat availability combines habitat amounts with interpatch connectivity, governing whether a landscape can shelter biological populations in the long term. Consequently, restoration efforts should focus on enhancing habitat availability to promote biological flows. In this study, we proposed a multi-scale approach to evaluate the effectiveness of restoration program and to set priority areas for forest restoration. The evaluations of effectiveness highlighted the contributions of forest cover change to habitat availability. The restoration priorities of landscapes were ranked by three indicators which are also tightly associated with habitat availability: relative urgency of intervention, efficiency of restoration, and connectivity importance for broader-scale biotic flows. We applied the approach in the Eastern Himalaya region of China, a global biodiversity conservation hotspot. Forest cover has been increasing by 3.4% in this region since 2000 due to the implementation of the Grain-for-Green Program, but not all the new forest areas were available as species habitat and/or stepping stones. By the method we developed, 14% of the areas are ranked as the high restoration priorities aiming to enhance available habitat for multiple species with different dispersal abilities. Our approach can significantly improve the outcome of a restoration program. It is flexible and can aid policy makers in optimizing restoration efforts given the biodiversity conservation goals and available resources. • Restoration effectiveness was evaluated in terms of habitat availability. • Grain-for-Green Program increased forest cover rather than habitat availability. • Priority areas can benefit multiple species with different dispersal abilities. • Our framework can promote the efficiency of a restoration program. • The method is flexible and not restricted by biological data deficiencies. [ABSTRACT FROM AUTHOR]

Ecotourism is considered to be an effective means of promoting nature conservation and sustainable development in less developed regions. However, its widespread adoption may be the result of a misunderstanding due to confusion about definitions and interpretations. Using web map browsers, we assessed the distribution pattern of ecotourism sites in both number and density in the 31 provinces of mainland China, and found that it positively correlated with gross domestic products (GDP) and population size, showing spatial dynamics similar to the general tourism model. However, negative-weak or no correlation at all was found with the presence and size of nature variables such as protected areas. These results support previous suspicions that the term ecotourism and its associated concept may be misused in China and that the regions that could benefit the most from this form of tourism have yet to properly develop it. Although this pattern could reflect a huge demand for genuine ecotourism, we recommend that China, to achieve its ambitious sustainable development goals, adapt ecotourism policies in its environmental and socio-cultural context, manage them with a trans-disciplinary expert board, and regulate its market by introducing a rigorous admittance system with continuous monitoring and evaluation. [ABSTRACT FROM AUTHOR]