Search Results (120)

Linear assets (LAs), such as conveyor systems, road networks, pipelines, and power transmission lines, are typically maintained through localized, segment-based interventions. While such approaches effectively address spatially heterogeneous degradation, they often neglect the system-level consequences of repeated local actions. In particular, improvements in segment condition may be accompanied by increased structural complexity, leading to reduced reliability and higher lifecycle costs. This paper proposes a unified engineering framework that integrates segment-level condition assessment with system-level structural effects. The framework is based on a dual representation of asset condition, distinguishing between material state (MS) and structural state (SS), which correspond to material aging (MA) and structural aging (SA), respectively. A key contribution is the introduction of the fragmentation penalty (FP), capturing the negative impact of increasing segmentation and interface density on system performance. The framework incorporates multi-threshold decision logic, enabling differentiation between operational, refurbishment, and replacement regimes, and interprets maintenance actions as transformations affecting both condition and structure. A formal model is developed to represent the asset as a dynamic system of segments and interfaces. It provides a basis for future empirical calibration and structure-aware optimization. Although the model is developed using conveyor belt loops as a reference case, its broader relevance is discussed for other classes of linear assets with repeated local intervention and evolving structural heterogeneity. A simple worked example is included to demonstrate the operational meaning of the proposed fragmentation-aware perspective. The results show that maintenance decisions may change when structural side effects are considered together with local condition improvement, and they provide a basis for future empirical calibration and structure-aware optimization of maintenance strategies. Full article

Campus streetscapes are a key part of universities’ everyday public realm, yet the same scene may be perceived positively in one dimension while negatively in another. To diagnose such multi-dimensional perceptual differences and translate them into actionable design evidence, this study develops an interpretable vision analytics framework for adaptive campus design. Using 72,733 Baidu Street View images collected from 41 campuses in mainland China, the study integrates ResNet-50-based perception prediction, spatial element extraction, XGBoost–SHAP-based mechanism interpretation, Kruskal–Wallis H testing, and GIS-based scene mapping. Supported by supplementary in situ validation, six types of multi-dimensional perceptual differences were identified. Sky, buildings, vegetation, hardscape, and terrain were found to be the five most important spatial elements overall, among which sky, buildings, and vegetation repeatedly emerged as the dominant core elements distinguishing different perceptual types. These elements do not act independently or linearly, but jointly shape different types of multi-dimensional perceptual differences through nonlinear threshold effects and interactions. These perceptual difference types were further found to cluster in recognizable campus scenes, including main roads, plazas, lawns, forest belts, and lakeside spaces. Based on these findings, scene-specific piecemeal optimization strategies were derived to support the coordinated enhancement of perceived safety, liveliness, and beauty. Overall, the study shows that campus perception is shaped by holistic spatial configurations rather than the simple accumulation of isolated elements, and provides a quantitative basis for iterative, feedback-oriented adaptive campus design. Full article

Frequent major emergencies threaten the security of the feed grain import supply chain. Enhancing import resilience is essential for supporting a new development pattern. However, research on a dedicated system to evaluate the resilience of China’s feed grain imports remains limited. In addition, strategies to strengthen resilience based on country-specific distances are still underexplored. This study constructs a comprehensive indicator system for China’s feed grain import resilience, using data from 2000 to 2023. It empirically examines the impact of country distance on this resilience across four dimensions: geographic distance, economic distance, institutional distance, and cultural distance. The findings indicate that country distance has an inhibitory effect on China’s feed grain import resilience. This conclusion holds true even after testing various adjustments, such as changes to core explanatory and dependent variables, modifications in sample sizes, alterations in measurement methods, and the introduction of instrumental variables. Further analysis reveals that country distance undermines feed grain import resilience by significantly reducing trade efficiency. However, the Belt and Road Initiative (BRI) and Regional Trade Agreements (RTA) help mitigate the negative impact of country distance on resilience. To strengthen China’s feed grain import resilience, it is crucial to enhance cultural and institutional trust, improve trade efficiency, and optimize import distribution. This study provides empirical evidence to support the safety of China’s feed grain imports and promote efficient, mutually beneficial trade in feed grains with partner countries. Full article

As urbanization intensifies, improving street thermal comfort has become a critical issue in urban renewal. While existing studies generally assume that increasing the Green View Index (GVI) linearly improves pedestrian thermal comfort, this study identifies a significant “Decoupling Effect” in high-density commercial areas through field measurements and numerical simulations of three typical street types (commercial–service, ecological–recreational, and historical–cultural) in Shenyang. Integrating DeepLab V3 semantic segmentation with ENVI-met version 5.1.1 microclimate simulation, the results demonstrate a robust monotonic negative correlation between GVI and Physiological Equivalent Temperature (PET) in ecological streets (Spearman’s ρ = −0.692, p < 0.001), confirming the consistent cooling benefit of greenery in nature-dominated environments. However, a distinct “Threshold Effect” was identified in commercial streets using Piecewise Linear Regression (PLR). A critical breakpoint was detected at GVI = 22.08%. Below this threshold, visual greenery effectively contributes to cooling (slope = −0.454); yet, once GVI exceeds 22.08%, the cooling efficacy diminishes significantly (slope = −0.109), marking the onset of a “decoupling” phase. Specifically, despite Wenhua Road achieving a GVI of ~24.5% with a complex “three-board, four-belt” structure, its PET peak reaches 46.15 °C, approximately 5.5 °C higher than ecological streets. Mechanism analysis reveals that under peak thermal stress (Traffic Heat ≈ 75 W/m²), the high-intensity anthropogenic heat and hardscape radiation exceed the evaporative cooling threshold of vegetation. This study reveals the non-linear relationship between visual greenery and the physical thermal environment, suggesting that simply pursuing visual green quantity is ineffective in commercial canyon renewal; instead, a threshold-based synergistic optimization of canopy shading and pavement thermal performance is required. These findings provide a quantitative basis for sustainable street landscape planning and urban climate adaptation strategies in high-density cities. Full article

This paper investigates the coordination between logistics and policy decisions for electric vehicle (EV) exports under the Belt and Road Initiative. Focusing on the two modes—maritime shipping and the China Railway Express (CR Express)—along with government production subsidies, import tariffs, and service premium, a Stackelberg game model for a cross-border supply chain comprising a domestic manufacturer and an overseas retailer is constructed. The equilibrium outcomes under four scenarios formed by combining subsidy policies and transportation modes (Models NM, NR, GM and GR) are compared theoretically and numerically, with further evaluation of capacity constraints and power structures, as well as the robustness verification of the core findings. Results show that the CR Express mode exhibits a service-driven nonlinear cost pattern, where its service premium amplifies positive market responses. Its appeal to the manufacturer, however, is tightly constrained by fixed cost. Furthermore, government subsidies can overcome this barrier by synergizing with the service premium, turning the CR Express into a relatively advantageous strategy. Moreover, subsidy efficacy is conditional, depending heavily on the service premium level and logistics cost coefficient, leading to a proposed differentiated subsidy framework. This study offers a theoretical basis for corporate logistics strategy and targeted policy design. Full article

As China has increased implementation of its opening-up strategy and the “Belt and Road” initiative, Chinese enterprises have encountered significant historical opportunities to expand their outward foreign direct investment (OFDI). However, international organizations and major nations are increasingly focusing on nonfinancial indicators for multinational corporations; as a result, enterprises frequently encounter social responsibility crises in cross-border investments. Consequently, Chinese firms must enhance their environmental, social, and governance (ESG) practices to bolster their comprehensive competitiveness, which is crucial for promoting successful international engagement and sustainability. This research explores the U-shaped relationship between ESG performance and OFDI, examining how different stages of the corporate lifecycle affect OFDI. The findings indicate that ESG investments compete with OFDI for internal resources during the introduction, growth, and decline phases, thereby inhibiting OFDI activities. In contrast, strong ESG performance in the maturity phase provides a competitive advantage in international markets, facilitating OFDI. The empirical analysis uses a fixed-effects model on a sample of Chinese A-share-listed companies from 2009 to 2022 and employs the PSM, 2SLS, and System GMM methods to test for endogeneity. The results reveal that (1) a positive U-shape relationship between ESG performance and corporate OFDI, and the inflection point occurs when the ESG score equals 69.04. Moreover, (2) the corporate lifecycle intensifies this nonlinear relationship, with growth-phase firms showing a significant inhibitory effect and mature-phase firms showing a pronounced promotional effect. Finally, (3) the U-shaped relationship between ESG performance and corporate OFDI is more pronounced in nonstate-owned enterprises. Based on these findings, this paper provides targeted policy recommendations for enterprises and governments. Full article

Campus community gardens are expected to leverage disciplinary resources and spatial conditions to deliver ecological, educational, and social benefits beyond those of general community gardens. In China, these gardens are primarily established under the guidance of educational authorities, leading to issues such as significant homogenization and a lack of diversity, which hinders the full realization of their potential. This study investigates the potential factors influencing the development of campus gardens. Focusing on university campuses in Beijing, it employs stratified sampling and a questionnaire survey (n = 1008), utilizing methods including exploratory factor analysis (EFA), multiple linear regression, and analysis of variance (ANOVA) to systematically identify the factors affecting their differentiated development. The results indicate that: (1) the willingness to participate is collectively driven by four dimensions: “planting expectation,” “funding and site selection,” “personal motivation,” and “organizational support,” with “planting expectation” being the most significant factor. (2) Students’ academic disciplines influence their perceptions of the need for organizational support and spatial resources for gardens. (3) Campus location and size moderate the demand for gardens, with students in the urban expansion belt (between the 4th and 5th Ring Roads) and those from smaller campuses showing a stronger “pro-nature compensation” tendency. Based on campus spatial scale, urban location, and the academic backgrounds of participants, the study proposes integrated “space-organization” development strategies. This research provides targeted planning strategies for campus community gardens in China, aiming to leverage institutional disciplinary strengths, respond to participant needs, and maximize the gardens’ benefits. Full article

Against the backdrop of rapid urbanization and land development, the degradation of regional ecosystem services and the intensification of ecological risks have become prominent challenges. This study takes the Pinglu Canal Economic Belt—a region characterized by the triple pressures of “large-scale engineering disturbance, karst ecological vulnerability, and port economic agglomeration”—as a case study. Based on remote sensing image data from 2000 to 2020, a landscape ecological risk index was constructed, and regional landscape ecological risk levels were assessed using ArcGIS spatial analysis tools. On this basis, ecological sources were identified by combining the InVEST model with morphological spatial pattern analysis (MSPA),and an ecological resistance surface was constructed by integrating factors such as land use type, elevation, slope, distance to roads, distance to water bodies, and NDVI. Furthermore, the circuit theory method was applied to identify ecological corridors, ecological pinch points, and barrier points, ultimately constructing the ecological security pattern of the Pinglu Canal Economic Belt. The main findings are as follows: (1) Ecological risks were primarily at low to medium levels, with high-risk areas concentrated in the southern coastal region. Over the past two decades, an overall optimization trend was observed, shifting from high risk to lower risk levels. (2) A total of 15 ecological sources (total area 1313.71 km²), 31 ecological corridors (total length 1632.42 km), 39 ecological pinch points, and 15 ecological barrier points were identified, clarifying the key spatial components of the ecological network. (3) Based on spatial analysis results, a zoning governance plan encompassing “ecological protected areas, improvement areas, restoration areas, and critical areas” along with targeted strategies was proposed, providing a scientific basis for ecological risk management and pattern optimization in the Pinglu Canal Economic Belt. Full article

Traffic noise is one of the main sources of environmental problems and a growing challenge for national traffic authorities. It is widely accepted that tire-pavement interaction is the main cause of traffic noise at speeds between 40 and 90 km/h. Typically, noise attenuation strategies include earthworks, tree belts, or noise barriers. However, a solution that is almost always viable is the use of low-noise pavements, which are characterized by their porous macrotexture, such as Stone Mastic Asphalt (SMA) mixtures. These mixtures are increasingly used for heavy traffic volumes because of their many advantages, including drainage properties and mechanical strength. Based on the experimental results obtained on different roads in southern Spain, this paper compares noise reduction in an SMA standard mixture due to the incorporation of different additives, such as crumb rubber and polymeric additives. According to the analysis, increasing the additives content by 1% reduces CPX by 1.18 decibels, approximately, and none of the analyzed sections shows increases greater than 3 dB within 24 months. Additionally, the paper proposes design recommendations regarding macrotexture and the percentage of voids for zones with warm, dry climates, such as Mediterranean Spain. Full article

Despite the well-established ability of urban green belts to reduce traffic noise, a comprehensive analysis of the specific role played by mixed coniferous trees and shrubs in noise mitigation remains lacking. This study aimed to clarify how different planting patterns and the characteristics of plants affect their noise-reduction performance. To achieve this, noise reduction was measured at 18 roadside green spaces comprising mixed coniferous trees and shrubs in Harbin, China, and Moscow, Russia. The results indicate that in lanes 5–15 m wide, the ‘Abreast’ planting pattern consistently offered greater noise reduction than the ‘Taffy’ configuration at all measured distances (5, 10 and 15 m). In addition, in winter the effectiveness of noise reduction improved due to snow cover, which enhanced the sound-absorbing properties of the vegetation. In our analysis, key factors such as diameter at breast height, minimum height under branches and road width emerged as crucial predictors of traffic noise reduction. Among these, carriageway width and sidewalk width exhibited the strongest correlations with noise attenuation. Finally, we developed a quantitative model for roadside green spaces that incorporates plant characteristics, planting schemes and road features. This model allows us to assess the contribution of each factor to overall noise reduction. The results of this study provide a scientific basis for designing and optimising vegetation-based noise-mitigation strategies to enhance the urban acoustic environment while also offering an analytical framework to support evidence-based urban forestry planning and policy. Full article

With the comprehensive implementation of the “Belt and Road” initiative and the Western Development Strategy, the scale of tunnel construction has been continuously expanding, with many tunnels being built in high ground stress and fractured soft rock strata. The design, construction, and operation of tunnels all rely on the surrounding rock pressure as a fundamental basis. Therefore, determining the surrounding rock pressure is essential for ensuring the safe construction of tunnels. However, due to the complexity of geological conditions, differences in construction methods, variations in support parameters, and time–space effects, it is challenging to accurately determine the surrounding rock pressure. This paper proposes a design approach using the surrounding rock pressure design value as the “support force” for the tunnel, starting with the reserved deformation of soft rock tunnels. Based on the calculation principle of the surrounding rock pressure design value, a relationship curve between the support force and the maximum deformation of surrounding rock in high ground stress soft rock tunnels is developed. By combining the surrounding rock deformation grade with the tunnel’s reserved deformation index, a calculation method for the surrounding rock pressure design value for high ground stress soft rock tunnels is proposed. The method is verified by the measured surrounding rock pressure data from the Mao County Tunnel of the Chengdu–Lanzhou Railway. Furthermore, the study integrates the creep characteristics and strain softening properties of soft rock to implement a secondary development of the viscoelastic–plastic strain softening mechanical model. Based on a custom-developed creep model and the calculation method for the surrounding rock pressure design value, the relationship among time, support force, and surrounding rock deformation is comprehensively considered. A calculation method for the surrounding rock pressure design value, accounting for time effects, is proposed. Based on this method, a time-history curve of the surrounding rock pressure design value is obtained and used as the input load. The safety factor time evolution of the rock-anchor bearing arch, spray layer, and secondary lining is derived using the load-structure method, and the overall safety factor time evolution of the tunnel support structure is evaluated. The overall stability of the support structure is assessed, and numerical simulations are compared with field measurements based on the mechanical behavior evolution law of the secondary lining of the Chengdu–Lanzhou Railway Mao County Tunnel. The results indicate that the monitoring data of the internal forces of the field support structure is in good agreement with the numerical calculation results, validating the rationality of the proposed calculation method. Full article

Here we present a high-resolution landslide susceptibility model for Guiyang County, China, developed to support sustainable disaster risk management. Our approach couples optimized positive and negative training samples with an ensemble of machine-learning algorithms to maximize predictive fidelity. We compiled a georeferenced inventory of 146 landslides by integrating historical records with systematic field validation. Sample optimization was central to our methodology: landslide presence points were refined via buffer-based dilution, and four classifiers—SVM, LDA, RF, and ET—were trained with identical covariate sets to ensure comparability. Three strategies for selecting pseudo-absences—buffering, low-slope filtering, and coupling with the IOE—were benchmarked. The Slope-IOE-O model, which synergizes low-gradient screening with entropy-weighted sampling, yielded the highest predictive capacity (AUC = 0.965). SHAP-based interpretability revealed that slope, monthly maximum rainfall, surface roughness, and elevation collectively dominate susceptibility, with pronounced non-linearities and interactions. Slope contribution peaks at 20–30°, monthly maximum rainfall exhibits a critical threshold near 225 mm, and the synergy between high roughness and road density amplifies landslide risk. Spatially, susceptibility follows a pronounced north–south gradient, with high-hazard corridors aligned along northern and southern mountain belts and the urban core of southern Guiyang County. By integrating rigorously curated training data with robust machine-learning workflows, this study provides a transferable framework for proactive landslide risk assessment, offering scientific support for sustainable land-use planning and resilient development in mountainous regions. Full article

This study uses provincial panel data from China (2014–2022) to examine the effect of agricultural outward foreign direct investment (OFDI) on agricultural imports. Employing panel regression, mediation effect, and spatial Durbin models, it explores the underlying mechanisms, spatial spillover effects, and regional heterogeneity, while emphasizing the role of OFDI in building sustainable agricultural supply chains. The results show that: (1) OFDI significantly promotes agricultural imports, enhancing the stability and diversity of the domestic supply, supporting food security, and facilitating the sustainable allocation of resources. (2) Mechanism analysis reveals that OFDI affects imports through reverse technology spillovers and improved international relations. (3) Heterogeneity analysis indicates that OFDI exerts stronger influence in major grain-marketing areas, production–marketing balance regions, and provinces along the Belt and Road, compared with grain-producing areas and non-Belt and Road provinces. (4) Spatial analysis based on the 0–1 adjacency matrix reveals that agricultural imports across Chinese provinces exhibit significant positive spatial autocorrelation. Furthermore, OFDI not only directly promotes agricultural imports within a given province but also generates notable positive spatial spillover effects, whereby OFDI in neighboring provinces likewise exert a positive influence on the province’s agricultural imports. To enhance the import effect of agricultural OFDI and stabilize the domestic supply of agricultural products, policy implications suggest that the government should adhere to the agricultural “going global” strategy, enhance enterprises’ capacity to absorb reverse technology spillovers, and explore regionally differentiated pathways for agricultural OFDI, among other policy recommendations. Full article

Amid an increasingly complex and uncertain global landscape, geopolitical tensions and frequent trade frictions have emerged as critical external risks threatening the economic stability and sustainable development of Chinese cities. Enhancing cities’ economic resilience has become a key challenge in advancing China’s high-quality development agenda. As a major national strategic initiative, the Belt and Road Initiative (BRI) is expected to offer new development opportunities and pathways for risk mitigation, particularly for cities situated along its domestic routes. This paper examines whether and how the BRI affects the economic resilience of these cities and further explores the moderating role of local governance capacity in policy implementation. To this end, an empirical strategy combining the entropy weighting method and the difference-in-differences (DID) approach is employed to systematically assess the impact of the BRI on urban economic resilience at the city level. The key findings are as follows: (1) The findings show that the BRI has an enhancing effect on the economic resilience of cities along the routes, but governance is very weak, and urban resilience improves by 0.0045 units on average. Our findings imply that, while the BRI appears to be on the correct path, enhanced governance is necessary to implement city-specific planning approaches effectively. (2) The results of the moderating effect indicate that local governance capacity significantly amplifies the impact of the BRI on urban economic resilience, underscoring the critical role of institutional strength in the policy transmission process. (3) The heterogeneity analysis reveals significant regional disparities in policy effectiveness: while the BRI significantly improves economic resilience in eastern and central cities, it exerts a suppressive effect in western regions. This divergence is closely associated with variations in local governance capacity. In contrast, cities with stronger governance capabilities are more likely to experience positive outcomes, as confirmed by the significant moderating effect of local governance capacity. This study contributes to the growing literature on the spatial implications of national development strategies by empirically examining how the BRI reshapes urban economic resilience across regions. It offers important policy insights for enhancing the spatial governance of cities, particularly in aligning strategic infrastructure investment with differentiated local capacities. The findings also provide a valuable reference for land-use planning and regional development policies aimed at building resilient urban systems under conditions of global uncertainty. Full article

The carbon dioxide spillover effects and influencing factors of the “Belt and Road Initiative” (BRI) in African countries must be assessed to evaluate the effectiveness, promote low-carbon transmissions in African countries, and provide recommendations for achieving the 2030 Sustainable Development Goals. This novel study employs carbon dioxide emission intensity (CEI) and per capita carbon dioxide emissions (PCE) as dual indicators to evaluate the spatial spillover effects of 54 BRI African countries on their neighboring countries’ carbon emissions from 2007 to 2023. It identifies the key factors and mechanisms affecting these spillover effects using the spatial differences-in-differences (SDID) model. Results indicate that since the launch of the BRI, the CEI and PCE of BRI African countries have significantly increased, largely due to trade patterns and industrialization structures. Greater trade openness has further boosted local economic development, thereby increasing carbon dioxide’s spatial spillover. Government management and corruption control levels show some heterogeneity in the spillover effects, which may be attributed to long-standing issues of weak institutional enforcement in Africa. Overall, this study reveals the complex relationship between BRI African economic development and environmental outcomes, highlighting the importance of developing sustainable development strategies and establishing strong differentiated regulatory regimes to effectively address environmental challenges. Full article