Urban renewal has entered a new stage where stock development is as important as quality improvement. At this stage, the urban renewal in policy new towns and ordinary new districts shows clearly distinguishable structural differences in terms of institutions, resources, and implementation. This study selects Qianhai and Xiongan as cases of policy new towns, and selects Bao 'an of Shenzhen and the main urban area of Baoding as ordinary new towns with the same geographic location, level and development period. The core focus of the study is the difference of urban renewal between policy new areas and ordinary new areas and which path will the next renewal take. Many documents indicate that policy-based new areas, leveraging their policy advantages, can shorten the decision-making process and gather information. In contrast, ordinary new areas have deficiencies in information acquisition and departmental collaboration, and urban renewal in these areas is prone to fluctuations and restrictions. For this purpose, we propose a differentiated urban renewal path centered on information governance, providing operational guidance for transitioning from pilot experience to large-scale promotion.

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Container terminals, handling over 80% of global trade, face a "triple dilemma": complex multi-equipment coupling, frequent disturbances, and stringent international carbon mandates like the IMO policies and EU ETS. Traditional optimization methods struggle with real-time adaptation and low-carbon compliance. Digital Twin (DT) technology offers a new paradigm for virtual–physical mapping and carbon efficiency management. This paper systematically reviews port digital twins and intelligent scheduling, constructing a four-dimensional framework: architecture, problems, technologies, and applications. Findings indicate that DTs are characterized by bidirectional closed-loop interaction, with a four-layer architecture becoming the mainstream paradigm. While scheduling models for multi-equipment collaboration are maturing, the research frontier has shifted toward DT-driven uncertainty rescheduling and low-carbon strategies, such as equipment ratio optimization and charging management. Core technologies—data fusion, virtual modeling, and reinforcement learning—are increasingly robust. Practical implementations in major hubs like Qingdao and Yangshan ports demonstrate that DT solutions significantly enhance operational efficiency and reduce emissions. Ultimately, DT technology provides a critical pathway for terminals to navigate international carbon regulations and achieve green, high-quality development.

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The evaluation of the geological environment carrying capacity of mines is crucial for achieving sustainable development and risk management of mines. This study proposes a spatio-temporal evaluation model that integrates remote sensing ecological indices and geological safety indices to take into account the surface ecological status of the mining area and underground geological safety. This method is based on the theoretical framework of "state-pressure-response", integrates multi-source remote sensing, InSAR, geology and other multi-temporal data, constructs RSEI through principal component analysis, builds GSI through analytic hierarchy process, and determines the weights using entropy weight method for comprehensive evaluation, generating the spatial distribution of carrying capacity. Taking the Pingshuo mining area in Shanxi Province as an example, the application of the model (from 2015 to 2024) shows that the high carrying capacity vulnerable areas present a "point-line-plane" composite feature, which is highly correlated with mining activities and structural zones. The verification indicates that the overall accuracy of the model is 86.4%, and it can identify 35% of the emerging deformation and ecological degradation risk areas that were underestimated by traditional methods, providing an effective spatialization tool for dynamic monitoring and precise control of the mining area environment.

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Magnesium silicate hydrate cement (MSHC) is considered a promising low-carbon alternative to ordinary Portland cement because of its lower calcination temperature and comparable mechanical performance. However, its application in reinforced concrete is limited by the corrosion risk of embedded steel, mainly associated with the relatively low alkalinity of the pore solution. This review summarizes the current understanding of the corrosion behavior and mechanisms of steel reinforcement in MSHC, with emphasis on passive film stability, chloride attack, and carbonation effects. Common evaluation methods, including electrochemical techniques and microstructural characterization, are also discussed. Existing studies indicate that although MSHC exhibits a relatively dense matrix and low chloride transport capacity, its weaker alkaline reserve reduces the stability of steel passivation compared with ordinary Portland cement. Current protection strategies mainly rely on modifying pore solution chemistry and improving interfacial conditions. Finally, key research needs are identified to support the durable application of reinforced MSHC in low-carbon construction.

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