Abstract: With the ageing population and the accelerating pace of urbanization, the demand for emergency medical services is experiencing sustained rapid growth. The traditional resource allocation model of ‘fixed stations plus return to base’ struggles to adapt to the dual time-varying characteristics of both resources and demand, resulting in an increasingly acute imbalance between supply and demand. This paper focuses on the dynamic return-to-base decision-making problem for ambulances that do not return to their original station upon completing a mission, and proposes a dynamic return-to-base strategy based on the Jarvis approximate hypercube model.This study advances ambulance return strategies from ‘static rule optimization to ‘dynamic online decision-making’, achieving an improvement from ‘single-objective’ to ‘multi-objective’ approaches, thereby providing theoretical and methodological support for the dynamic allocation of emergency resources Read More

Abstract: With the rapid development of the healthcare industry in China, the safe and efficient disposal of medical waste (MW) has become a critical issue in environmental governance and public health safety. The traditional territory-based MW disposal model has caused severe resource mismatch between the bordering areas of Shanghai and Jiangsu, where geographical proximity coexists with fragmented administrative governance. To solve this contradiction, this study converts the intangible administrative barrier into measurable administrative coordination cost, and establishes a bi-objective optimization model with the core objectives of minimizing total comprehensive cost and minimizing total carbon emissions. Aiming at the limitation of traditional K-means algorithm that only relies on geographic distance, an improved K-means clustering algorithm integrated with administrative cost and carbon cost weights is designed, and combined with an improved Genetic Algorithm (GA) to complete model solving. Taking Chongming District of Shanghai and Qidong City of Jiangsu as the empirical case, this study conducts a quantitative analysis with 218 medical institutions as research samples. The results show that compared with the traditional independent disposal model within administrative regions, the optimized cross-regional collaborative scheme reduces the total transportation mileage by 18.04%, the total operation cost by 13.20%, and the total carbon emissions by 17.65%, while increasing the 48-hour collection and transportation compliance rate from 92.5% to 99.8%. This study provides a scientific decision-making reference for cross-regional MW governance in the Yangtze River Delta, and offers a replicable theoretical framework for breaking administrative barriers and promoting the low-carbon transformation of reverse logistics networks. Read More

Abstract: With the official opening of the Pinglu Canal, the core backbone project of the New Western Land-Sea Corridor, the demand for clean energy refueling infrastructure for inland shipping has increased sharply. Liquefied Natural Gas (LNG), as a low-carbon and efficient ship fuel, has become the main direction for the green transformation of inland shipping. However, the current site selection of LNG refueling stations along inland rivers faces problems such as single evaluation dimension, strong subjectivity in weight determination, and lack of spatial quantitative analysis. To address these issues, this paper constructs a suitability evaluation index system for LNG refueling stations along the Pinglu Canal from four dimensions: waterway and navigation conditions, market demand conditions, resource and infrastructure conditions, and safety and environmental conditions. A combination weighting model integrating Analytic Hierarchy Process (AHP) and Entropy Weight Method (EWM) is established to determine the index weights, which effectively balances the subjectivity of expert judgment and the objectivity of data information. Combined with Geographic Information System (GIS) spatial analysis technology, the single-factor raster layers are superimposed and analyzed to obtain the comprehensive suitability distribution map of LNG refueling stations. The results show that the highly suitable areas for LNG refueling stations along the Pinglu Canal are mainly concentrated in the Qinzhou Port section, Luwu Town section and Xijin Reservoir area of Hengzhou, accounting for 4.2%, 2.5% and 2.0% of the total study area respectively (totaling 8.7% of the total region). Finally, 5 optimal alternative sites are proposed, which can provide scientific decision-making basis for the planning and construction of LNG refueling infrastructure along the Pinglu Canal. Read More

Abstract: Vehicle distribution is a critical link in logistics activities that directly connects with customers, and distribution costs account for a significant proportion of overall logistics operations. This paper aims to solve the vehicle scheduling problem faced by logistics enterprises in practice and proposes an optimization model for the Capacitated Vehicle Routing Problem based on the Ant Colony Algorithm. The main purpose of the study is to improve vehicle utilization efficiency and reduce operating costs by optimizing distribution paths. The experimental results show that the Ant Colony Algorithm has high efficiency and feasibility in solving the vehicle scheduling problem with capacity constraints, effectively reducing logistics distribution costs and providing a viable solution for practical logistics vehicle scheduling. Read More

Abstract: With the growth of container shipping demand and the increasing size of vessels, the scarcity of frontline port resources, such as berths and quay cranes, has become increasingly prominent. Traditional port operations usually treat berth allocation, quay crane assignment and charging mechanisms as separate decisions, making it difficult to fully reflect the internal relationship among resource scarcity, differentiated service demand and port revenue management. As a differentiated service with service commitment attributes, berth priority usage rights can guide vessels’ choices through pricing mechanisms and provide a new approach for optimizing port resource allocation and improving revenue. Therefore, this thesis studies the pricing problem of berth priority usage rights, focusing on the coordinated optimization relationship among priority pricing, berth planning and quay crane allocation. This thesis first defines the service connotation of berth priority usage rights, regarding them as differentiated services in which the port provides vessels with earlier latest service completion commitments. On the demand side, reservation price and consumer utility theory are introduced to describe vessels’ willingness to pay for different priority levels. Vessels make choices according to the net utility formed by the difference between the reservation price and the actual price of each level. When positive net utility exists, a vessel chooses the priority level with the highest utility; when all paid priority levels fail to provide positive net utility, the vessel chooses the non-priority option. In this way, the priority price is not only a charging parameter, but also an important decision variable that affects vessels’ priority-level choices, demand structure and resource allocation results. Read More

Abstract: Critical mineral supply chains—encompassing lithium, cobalt, and rare earth elements (REE)—underpin the global clean energy transition yet remain acutely vulnerable to multi-tier disruption cascades. Existing forecasting frameworks based on recurrent architectures or static Bayesian networks capture sequential dependencies but fail to distinguish genuine causal pathways from spurious temporal correlations, limiting their capacity to identify which network nodes amplify shocks across tiers. This paper introduces a causal Transformer (CT) architecture that integrates multi-head attention with a structural causal model (SCM) layer constrained by a directed acyclic graph (DAG) encoding domain knowledge. Applied to a four-tier network spanning extraction, processing, intermediate manufacturing, and end-use assembly for lithium-ion battery and permanent-magnet supply chains, the CT achieves F1 scores of 0.823–0.891 for cascade onset detection and a mean absolute error (MAE) of 0.97–1.31 tiers for propagation depth, outperforming long short-term memory (LSTM), gated recurrent unit (GRU), standard Transformer, and static Bayesian network baselines. Causal attribution identifies processing-tier geographic concentration as the dominant cascade amplifier, with Democratic Republic of Congo cobalt refining and Chinese REE separation collectively responsible for 63% of detected cascade events. Results carry direct policy implications, arguing for strategic stockpiling calibrated to processing-tier inventory compression cycles rather than extraction-tier geological events. Read More

Abstract: Maritime congestion at major global container ports represents one of the most pressing logistical bottlenecks of contemporary trade, with cascading consequences that permeate supply chains, freight economics, and carbon accounting simultaneously. This paper proposes a multimodal intelligence framework that integrates heterogeneous data streams — encompassing AIS positional records, meteorological observations, historical berth logs, and satellite-derived imagery — within a unified deep learning pipeline to forecast port congestion and optimize berth scheduling. A CNN-LSTM-GRU hybrid network with a cross-modal attention fusion layer is trained and evaluated on two-year real-world vessel traffic data from the Port of Shanghai and the Port of Singapore. Experimental results demonstrate that the proposed framework achieves a 23.7% reduction in MAE and a 19.4% reduction in RMSE relative to single-modality LSTM baselines. A downstream berth optimization module, driven by the congestion prediction output, reduces mean vessel waiting time by 17.6% under controlled simulation conditions. These findings confirm that multimodal data fusion constitutes a critical architectural principle for next-generation port intelligence systems. Read More

Abstract: In the context of global energy transition and sustainable development, liquefied natural gas (LNG) is becoming more and more prominent due to its clean and efficient advantages. As a key equipment in the LNG industry chain, gasifiers have a significant impact on their performance and efficiency, and different types of gasifiers have their own characteristics. This study aims to deeply explore the selection and application of LNG gasifiers, and establish scientific selection methods and application strategies through a comprehensive analysis of different types of gasifiers. From a theoretical point of view, it can fill the gaps in the comprehensive evaluation and systematic comparison of existing studies. In practice, it can ensure stable energy supply, reduce costs, and promote industrial technological progress. There has been progress in this field at home and abroad, but there are still problems such as imperfect multi-objective optimization and the need to strengthen reliability and safety. The innovation of this study lies in the multi-dimensional comprehensive analysis, the combination of qualitative and quantitative, and the focus on new technologies and application scenarios, providing strong support for LNG projects. Read More

Abstract: To further investigate the influence of leakage direction in buried pipelines on gas diffusion within soil, this study develops a fluid–solid coupled numerical model based on the unified Darcy–Brinkman–Biot equations. The migration behavior of methane and crack evolution characteristics under single-side, adjacent double-side, and three-side leakage conditions are systematically simulated and compared. The results show that leakage direction directly determines the geometric configuration of soil cracks by altering the initial kinetic energy distribution and local gas pressure. As the number of leakage directions increases, the number of cracks increases significantly; however, due to energy dispersion, the length and width of individual cracks decrease. The three-side leakage condition exhibits the highest peak pressure in the initial stage (exceeding 3700 Pa), which drives the formation of a more complex and dispersed crack network. In addition, the evolution of methane concentration fields is highly consistent with crack development. As the main cracks penetrate the boundaries and form stable flow channels, the gas transport mechanism transitions from pore diffusion to rapid transport along crack pathways, exhibiting a pronounced channeling effect. These findings provide important numerical evidence for urban pipeline safety monitoring and risk assessment. Read More

Abstract: To address the engineering challenge of debonding failure of the “second interface” (between the cement sheath and the formation rock) induced by alternating thermal-mechanical loads during geothermal well cementing, this study systematically investigated the reinforcement mechanism of a hybrid system of graphene and carbon nanotubes (CNTs) on the second-interface bonding performance of cement stone, using typical sandstone cores from the Ordos Basin as the substrate. The evolution of interfacial bond strength and failure mode under different CNTs contents (0%–0.12%) was evaluated by push-out shear tests. Combined with microstructural characterization techniques such as FE-SEM and EDS, the densification and toughening mechanisms of the interfacial transition zone (ITZ) were revealed from the perspectives of morphological evolution, element migration, and chemical bonding. The results showed that the 28-day second-interface bond strength reached 8.20 MPa, representing an approximately 15-fold increase compared to the baseline group (0.51 MPa). The shear stress–slip curve transitioned from a brittle “cliff-like” drop to a “pseudo-ductile” failure with serrated rebounds, indicating significantly enhanced fracture toughness. Microstructural analysis confirmed that graphene provided “template nucleation” and a two-dimensional skeleton, while CNTs played a “bridging–pull-out” energy dissipation role spanning cracks. Together, they constructed a “line-surface” three-dimensional interpenetrating network, reducing the interfacial Ca/Si atomic ratio from 0.59 to 0.43 and driving the interface bonding from physical van der Waals forces to chemical covalent bonds (Si–O–Si/Si–O–Ca). Excessive CNTs (≥0.12%) led to agglomeration, forming stress concentration sites and causing a decline in strength. This study provides a theoretical basis and material proportioning reference for the integrated design of “high thermal conductivity” and “strong interface” in geothermal well … Read More

Abstract: The Shanxi Formation in the Ordos Basin is an important strata for continental shale gas exploration in China. The study of the geochemical characteristics of its desorbed gas and the main controlling factors of reservoir formation is of great significance for resource potential assessment and development optimization. Based on the core samples from Well Chang96 and Well Yan2156 in the southeastern part of the basin, this paper systematically analyzes the characteristics of desorbed gas from shales in the Shanxi Formation. The research results show that: (1) The shale gas in the Shanxi Formation is mainly high-maturity thermogenic dry gas. The proportion of methane ranges from 80% to 93% (with an average of 80.05% in Member 1 and 84.02% in Member 2). The content of heavy hydrocarbons is extremely low (<0.3%), and the methane coefficient is >0.99. The non-hydrocarbon gases are mainly CO₂ and N₂ (with an average of 14% - 16%), and some are affected by air mixing. (2) The content of desorbed gas is closely related to lithology and organic matter abundance. Carbonaceous mudstone has the highest desorbed gas content, while fine-grained rocks such as mudstone and siltstone have significantly lower desorbed gas content, which is mainly controlled by differences in organic carbon content. (3) The desorbed gas content of shale gas in the Shanxi Formation of the Ordos Basin is low, which restricts resource potential assessment and favorable area prediction. This study provides a scientific basis for the efficient exploration and development of shale gas in the Ordos Basin and contributes to the improvement of the theoretical and technical systems for continental shale gas. Read More

Abstract: Bridges are important infrastructure for China's modernization. Currently, China's bridge construction scale, technical level, especially the construction level of long-span bridges, has leapt to the forefront of the world. Cable-supported bridges include cable-stayed bridges and suspension bridges. For bridge projects with a span exceeding 1000 m, cable-supported bridges are the only bridge type choice. Many early-built long-span cable-supported bridges at home and abroad have experienced service performance degradation during their service life. The actual service life of bridges is far shorter than the design life, one of the important reasons being the lack of management and maintenance. The domestic mainstream bridge maintenance management method is manual inspection, which is relatively passive, time-consuming, and has high repair costs. In recent years, UAV technology, robotics, machine learning algorithms, and LiDAR point cloud-based 3D reconstruction technology for buildings have made significant progress. Researchers have developed various bridge disease detection equipment and methods, some of which have been applied in practical engineering. This paper mainly introduces the main disease forms of cable-supported bridges and some research directions and achievements of intelligent detection technology, and analyzes the advantages and disadvantages of different intelligent detection technologies and equipment. Read More

Abstract: Automotive safety is the cornerstone of transformation in the transportation sector and a key pillar for safeguarding road traffic safety and sustaining the steady development of the industry. The advancement of automotive safety is not only pertinent to the lives, health and property security of road users, but also exerts a profound impact on the high-quality development of the automotive industry and the harmonious and stable operation of society. Continuously promoting the improvement of automotive safety levels is of great significance. Read More

Abstract: With the increasing scale and complexity of chain supermarkets, inventory management in multi-dimensional spatio-temporal data environments becomes more challenging, as traditional methods fail to handle regional demand heterogeneity. This paper proposes an integrated inventory management approach that leverages spatio-temporal data by combining the DeepAR probabilistic forecasting model with the newsvendor model for region-specific optimization. Sales regions are divided into five areas, and four demand-influencing features are selected. The DeepAR model, with a Gaussian likelihood, estimates demand distributions for each region. Experimental results show stable training convergence and high prediction interval coverage (PICP above 0.85 for most regions), while adaptively widening intervals in data-scarce or highly seasonal regions. These forecasts are then used in the newsvendor model to determine optimal order quantities by minimizing overage and underage costs. The proposed framework enables differentiated inventory strategies, improving service levels and operational efficiency. Read More

Abstract: With the continuous growth of China’s economy and the improvement of living standards, consumers have increasingly higher expectations for product quality. To meet market demand and promote industrial upgrading, enterprises are accelerating product renewal and placing greater emphasis on product design and quality assurance. However, this has also led to rising operating costs and declining profit margins. Therefore, reducing unnecessary daily expenses has become an important issue for enterprises, and workshop layout optimization is one effective way to improve operational efficiency and reduce costs. FlexSim is a computer-based simulation software used to model discrete-event processes, and it is widely applied in manufacturing, material handling, and office workflow analysis. In this study, POSCO-OSTEM (Suzhou) Automotive Parts Co., Ltd. in Kunshan is selected as the research object. Based on its workshop layout and production process, a production flow simulation model is established. Following the Systematic Layout Planning method, the production process and workshop layout are analyzed and improved, with the aim of developing a practical layout optimization scheme to reduce on-site management costs. Read More

Abstract: China’s urban development has entered a stage dominated by stock renewal, and the renovation of old residential communities has become an important starting point for high-quality urban development. The concept of complete community and the 15-minute living circle planning provide key guidance for the renewal of old communities. Based on the perspective of human geography, this paper takes old communities in Xi’an as the research object, constructs a three-dimensional analysis framework of “spatial facilities – service system – governance mechanism”, and systematically analyzes the practical dilemmas and explorations in the renovation of old communities. The study finds that the renovation of old communities in Xi’an is confronted with the coexistence of aging infrastructure and spatial resource constraints, mismatched supply and demand of public services and prominent shortcomings in full-age services, immature multi-stakeholder co-governance mechanism and lack of long-term management. Although distinctive experience has been formed in Party-building leading grassroots governance, there are still multiple tensions between patchwork renovation and systematic renewal demand, administrative leadership and resident participation. On this basis, it puts forward the optimization path of complete community construction from three dimensions: spatial reshaping, service embedding and governance restructuring, emphasizing solving spatial constraints through systematic renewal, filling service shortcomings through experience orientation, and building a long-term mechanism through multi-stakeholder co-governance. The study points out that the ultimate goal of old community renovation is to realize the leap from “living container” to “complete living community”. The construction of complete community is not only a realistic path for urban renewal in Xi’an, but also a livelihood practice to improve residents’ sense of happiness. It also reveals the internal connection between … Read More

Abstract: The effective performance evaluation of highly qualified specialists (HQS) remains a persistent challenge for Chinese enterprises transitioning to knowledge-intensive operations. Traditional evaluation systems, designed for routine work, fail to capture the multidimensional nature of HQS contributions, which encompass cognitive engagement, value congruence, and affective attachment. This study addresses this gap by developing and validating a comprehensive performance evaluation system specifically tailored to HQS. Using a mixed-methods design, the study first identified 22 candidate indicators through literature review and expert interviews. Rough set theory was then applied to reduce redundant indicators, yielding a parsimonious 17-indicator system organized across four dimensions: work engagement (5 indicators), organizational identification (4 indicators), value identification (4 indicators), and emotional belonging (4 indicators). Analytic Hierarchy Process (AHP) was subsequently employed to determine indicator weights, revealing that value identification (weight = 0.4564) and emotional belonging (weight = 0.2219) are the most influential criterion-level dimensions. At the indicator level, company culture (0.1896) and management systems (0.1336) emerged as the most heavily weighted individual measures. Confirmatory factor analysis (CFA) of survey data from 562 HQS in Chinese enterprises demonstrated good model fit (χ²/df = 2.462, GFI = 0.940, CFI = 0.939, RMSEA = 0.051), providing empirical validation of the proposed system. This study contributes a theoretically grounded, empirically validated, and practically operational evaluation system that enables Chinese enterprises to assess HQS performance more comprehensively and systematically. Read More

Abstract: Effective recycling and reuse of retired power batteries have become a critical issue for their sustainable development in the future. Currently, the market for retired power battery recycling is plagued by problems such as mixed recycling channels and lack of information transparency. Blockchain offers solutions for the full life-cycle management of power batteries. Thus, how to leverage blockchain to promote the efficient recycling and reuse of retired power batteries has emerged as a key issue. Considering two recycling channels and reuse modes empowered by blockchain, this paper establishes long-term dynamic decision-making models of the power battery closed-loop supply chain (PB-CLSC) using differential game, derives the feedback equilibrium strategies of all stakeholders. Furthermore, the impact of different recycling and reuse strategies with blockchain is thoroughly investigated, identifying the optimal recycling and reuse strategies. Read More

Abstract: To address the issues of insufficient injection capacity and slow energy replenishment associated with conventional waterflooding development in low-permeability oil reservoirs, this study takes typical low-permeability core samples from the X block in the eastern Yin'e Basin as the research subject. A systematic series of experiments on rock mechanics, single-phase and two-phase seepage, and imbibition is carried out to reveal the mechanical response of the reservoir, the evolution of seepage capacity, and the redistribution characteristics of residual oil under pressure-driven water injection conditions. The results indicate that pressure-driven water injection can significantly improve pore-throat connectivity and flow pathways, thereby enhancing the co-permeability of oil and water phases. In addition, imbibition oil displacement facilitates further mobilization of residual oil in medium and large pores. Read More

Abstract: With the rapid acceleration of prefabricated construction worldwide, new architectural wall panels have emerged as a critical vanguard of sustainable, high-efficiency engineering. Serving as a new generation of cement-based composites and lightweight structural assemblies, modern prefabricated panels feature ultra-high strength, exceptional toughness, superb thermal or acoustic insulation, and outstanding durability. This paper provides a comprehensive, deep-dive academic review synthesizing recent advancements across ultra-high space embedded wall panels, autoclaved lightweight aerated concrete (ALC) panels, light steel keel wallboards, and layered concrete-insulated composite systems. By aggregating recent empirical and numerical datasets, this review systematically dissects material composition optimization, joint connection mechanisms (rigid vs. flexible), structural reinforcement parameters, and multi-criteria lifecycle evaluation index systems. The findings demonstrate that while prefabricated wall technologies are maturing rapidly, critical challenges remain regarding the optimization of structural composite action, the elimination of localized thermal bridges, and the harmonization of objective-subjective lifecycle weighting. This review highlights prospective research paradigms to guide multi-scale testing, numerical standardization, and intelligent construction in green infrastructure. Read More