Characteristics, causes, and prevention measures of coal mine water hazard accidents in China

As one of the top “five major hazards” in coal mines, water hazards have become the second leading cause of danger for coal mine safety and worker lives, next only to gas accidents. Between 2000 and 2022, a total of 1206 water hazard accidents occurred in coal mines in China, resulting in 5018 deaths, among which 103 larger-scale events resulted in 2039 deaths. In order to identify accident patterns, summarize lessons learned, and promote prevention of water hazard accidents, various aspects were analyzed statistically, including geographical regions, years, seasons, hydrogeological types, water sources, and ownership of coal mines. Analyses revealed that the complexity of hydrogeological conditions highly correlated with the frequency of water-related accidents. Southern China recorded the highest number of incidents and casualties, and the peak incidence periods throughout the year mainly concentrated in March to May and July to August. Goaf water was identified as the primary source of water filling, which presented strong concealment and harm, mainly occurring in township-owned coal mines with weaker technical exploration and management capabilities. As for the causes of accidents, complex mining environments and insufficient attention subjectively, i.e., improper management and illegal mining, were the main reasons for accidents. Hidden water-bearing structures such as point-like collapse columns and linear fault structures, as well as goaf water that were not explored and placed in accordance with regulations, were identified as the main technical causes of accidents. By analyzing bibliometrics, it was found that current research themes focusing on coal mine water disasters align well with the principles of “predicting and forecasting, exploring if in doubt, exploring before mining, treating before mining”. To address the problems of “unclear risk assessment, inaccurate risk identification, and incapability to cope with accidents” in coal mine water disasters, corresponding countermeasures were proposed in three aspects: surveying filling factors and hidden geological factors causing disasters, analyzing three-dimensional hydrogeological conditions of filling water, and implementing an accurate classification source prevention. In response to the trend of informationization and intelligent development of water disaster prevention and control, technical measures such as transparent mines, water disaster monitoring and early warning, and emergency rescue were proposed

A grazing Gomphotherium in Middle Miocene Central Asia, 10 million years prior to the origin of the Elephantidae

Feeding preference of fossil herbivorous mammals, concerning the coevolution of mammalian and floral ecosystems, has become of key research interest. In this paper, phytoliths in dental calculus from two gomphotheriid proboscideans of the middle Miocene Junggar Basin, Central Asia, have been identified, suggesting that Gomphotherium connexum was a mixed feeder, while the phytoliths from G. steinheimense indicates grazing preference. This is the earliest-known proboscidean with a predominantly grazing habit. These results are further confirmed by microwear and isotope analyses. Pollen record reveals an open steppic environment with few trees, indicating an early aridity phase in the Asian interior during the Mid-Miocene Climate Optimum, which might urge a diet remodeling of G. steinheimense. Morphological and cladistic analyses show that G. steinheimense comprises the sister taxon of tetralophodont gomphotheres, which were believed to be the general ancestral stock of derived “true elephantids”; whereas G. connexum represents a more conservative lineage in both feeding behavior and tooth morphology, which subsequently became completely extinct. Therefore, grazing by G. steinheimense may have acted as a behavior preadaptive for aridity, and allowing its lineage evolving new morphological features for surviving later in time. This study displays an interesting example of behavioral adaptation prior to morphological modification

What Determines the Success of Culture-Led Regeneration Projects in China?

Culture-led regeneration projects (CRPs) have been identified as an effective means for enhancing the sustainable development of cities. Related topics have been investigated; however, relatively little information is known about what factors are critical for achieving success in these kinds of regeneration projects. Based on a literature review and five case studies, this study contributes to the body of knowledge by identifying 25 critical success factors (CSFs) for managing CRPs in China. A questionnaire survey was designed to evaluate the relative importance of these factors from practitioners’ and researchers’ perspectives. In addition, a factor analysis was carried out to group these CSFs into five categories, namely government policies and culture-led regeneration strategies, stakeholder management and financing support, technical solutions for CRPs, social security, and industry development. The results demonstrated that cultural value management, integrating cultural development with urban planning, adopting sustainable development principles, reconstructing the city image and brand, and the availability of culture-led planning methods played the most important roles in the success of CRPs. The findings of this study can help practitioners enhance their regeneration project performance

International competitiveness and potential for trade cooperation on clean energy between the USA and China

As two super powers in energy consumption and carbon emission, the United States and China have been striving to develop clean energy in recent years. In this paper, we study the international competitiveness and potential for trade cooperation in clean energy between the two countries. This paper reveals that the United States has comparative advantages in terms of biomass energy and nuclear power, while China has comparative advantages in terms of solar energy and wind energy. The two countries have a strong complementarity in solar energy, biomass energy and nuclear energy with exporting from the United States and importing from China. In solar energy and wind energy a strong complementarity has been formed with exporting from China and importing into the United States. So the two countries have a strong potential for cooperation. Meanwhile, the potential trade cooperation is enhancing with the United States accelerating the development and exportation in natural gas. Therefore, the two countries have a strong trade complementarity on clear energy and a strong potential for cooperation in general. At the same time, the VCR model is built based on the clean energy Trade Complementary Index(TCIc and TCIu) between the United States and China. It can be found that the clean energy trade cooperation helps to curb CO2 emissions and promotes the GDP growth in the United States. However, China is in the early stage of clean energy development, the cooperation would cause a decline of GDP in China

Unit Commitment of a Power System Including Battery Swap Stations Under a Low-Carbon Economy

Battery swap stations (BSSs) are of great importance as an energy supplement for electric vehicles (EVs). The batteries in these stations not only charge instantaneous energy from the grid (G2B) but also discharge stored energy to the grid (B2G). This bidirectional energy consuming scheme provides more flexibility to the grid operation options, and henceforth, may bring in new challenges to the systems as well. In the meanwhile, the carbon trading mechanisms for the low-carbon economy can also have impacts on the generation scheduling of the power system. Therefore, a unit commitment (UC) model of the power system with BSSs in the low-carbon economic background is proposed to coordinate the G2B/B2G process of BSSs. Our model weighted the carbon dioxide emission in the cost function and tightened the constraint set with BSSs limits and the carbon trading mechanism. Case studies on a 10-unit test system demonstrate the effectiveness of the proposed model

The Spatial Pedigree in Traditional Villages under the Perspective of Urban Regeneration—Taking 728 Villages in Jiangnan Region, China as Cases

In current urban regeneration, the conservation and reuse of traditional village space are significant measures to activate urban-rural development. Traditional villages in the Jiangnan region of eastern China represent the typical vernacular culture of urban-rural settlements, which affects the dynamic development of urban regeneration. Aiming at the disadvantages of the decentralization of research objects and the simplification of spatial characteristics in the research of traditional villages in the Jiangnan region, this paper will construct the spatial pedigrees of villages. This study takes 728 traditional villages in the Jiangnan region as cases. First, through on-site research, the spatial pattern of villages in isolated areas was mapped and drawn. Then, on the basis of on-site review, this study labeled the village space, summarized village space information, and used ArcGIS and BIM to create a 3D model of the village. In ArcGIS platform through SOA to establish criterion framework for recognizing the types of village pedigree. Finally, the classification of villages was spatially visualized, and a pedigree was constructed according to the type context. The research result indicates: (1) The aggregation mode of traditional villages in the south of the Jiangnan region presents the characteristics of local aggregation and partial dispersion, which are directly affected by factors such as elevation, water system, and road system. (2) Analysis of the spatial pedigrees of traditional villages through spatial types and spatial growth patterns revealed four pedigree types, including spatial environment pedigree, the spatial organization pedigree, spatial morphological pedigree, and architectural form pedigree. (3) The pedigree shows and distinguishes independent developmental context and evolved form, presenting an extended pattern of prototypes and sub-types