Search Results (34)

The Jiangsu Yangtze River city cluster is a key growth pole of the Yangtze River Economic Belt, yet substantial disparities in development levels persist across cities, and the role of rail transit investment in fostering regional economic coordination remains insufficiently understood. This study aims to reveal the dynamic mechanisms through which railway transportation investment influences regional economic growth via population migration and service industry agglomeration, and to quantify the economic multiplier effects under different investment scenarios. Considering the close economic linkages among cities, spatial autocorrelation analysis is applied to assess intercity economic dependence, which provides the basis for developing a system dynamics model that links the rail transit system with the regional economy. Using data from eight core cities over the period 2014–2023, the model is employed to simulate long-term economic responses under different investment scenarios. The results indicate that increasing the rail transit investment ratio from 0.0077 to 0.02 is associated with an estimated 13.2% increase in regional GDP by 2030, with a corresponding economic multiplier of approximately 1.8, while simulation errors remain within 4.1–16.2% compared with historical data. The findings suggest that rail transit investment promotes regional growth through improved accessibility, factor agglomeration, and industrial upgrading, and that coordinated planning at the urban agglomeration scale is more effective than isolated city-level strategies. By integrating spatial dependence analysis with system dynamics modeling, this study offers a dynamic perspective on the regional economic impacts of rail transit investment. Full article

To elucidate the micromechanical origins of the macroscopic anisotropic behavior of granular materials, this study develops a micromechanically based elastoplastic constitutive model for sand. First, anchored in the static equilibrium hypothesis and granular micromechanics theory, a true stress tensor is introduced to characterize the authentic inter-particle contact forces. Serving as a coupled variable of the macroscopic stress and the microscopic fabric tensor, this formulation not only quantifies the directional distribution of the contact network but also enables the mapping of anisotropic yielding and deformation analyses into an equivalent isotropic true stress space. Subsequently, a comprehensive constitutive framework is established by integrating critical state theory, an anisotropic fabric evolution law, and an energy-based stress–dilatancy relationship that explicitly accounts for the evolution mechanism of the microscopic coordination number. The physical interpretation, calibration procedure, and sensitivity analysis of the model parameters are also presented. The predictive capability of the model is rigorously validated against conventional triaxial tests on Ottawa sand, true triaxial numerical simulations, and experimental data for Toyoura sand with inherent anisotropy. The comparisons demonstrate that the model accurately captures not only the stress–strain response and volumetric deformation under conventional loading but also the strength dependency on loading direction and mechanical characteristics under complex stress paths, substantiating the validity and universality of the proposed micromechanical approach. Full article

Urban rail transit system planning is significant for alleviating traffic congestion and optimizing spatial resource allocation in cities with scarce land resources. However, the long period of rail transit construction, large-scale investment, and its planning involve a variety of factors, which require scientific and reasonable evaluation methods to ensure that its construction can realize the expected economic and social benefits. To solve this problem, this study first establishes an appropriate evaluation system by selecting suitable evaluation indicators. Then, the comprehensive assignment method combining the ordinal relationship method (G1 method) and the improved entropy weight method is applied to assign weights to the indicators in the evaluation system, and the correlation degree is calculated by combining with the matter-element model for evaluating the planning scheme of the urban rail transit system. Finally, the urban rail transit system planning scheme of Zhengzhou City is verified by example. The results show that the proposed method can balance the practical significance and dynamics of the evaluation indices, evaluate the importance of each index more objectively, and provide methodological support for dynamic decision-making in rail transportation planning in the context of a smart city, which is of guiding significance for the sustainable development of the city. Full article

The hybridization of ADM-Type Rail Service Cars aims to enhance energy efficiency, environmental sustainability, and cost-effectiveness within Uzbekistan’s railway network. Diesel-powered service cars currently contribute to high fuel consumption, elevated emissions, and costly maintenance, necessitating a transition to hybrid technology. This study introduces an innovative “sequence of linear sets–torsion electric motor–wheel pairs” design, optimizing torque distribution and power efficiency for improved operational reliability. Through system modeling, performance simulations, and real-world field trials, the hybrid system demonstrates a 15% reduction in energy consumption, a 25% decrease in CO₂ emissions, and up to 30% lower maintenance costs compared to conventional diesel models. Additionally, the hybrid technology enhances operational flexibility, allowing seamless functionality on both electrified and non-electrified railway lines. From an economic perspective, retrofitting existing service cars instead of full fleet replacement provides a cost-effective alternative, offering an estimated 10-year return on investment (ROI) through fuel savings and reduced downtime. This initiative directly supports Uzbekistan’s Green Development Strategy and railway modernization plans while holding significant commercialization potential in Central Asia and other regions with aging railway infrastructure. By addressing technical scalability, regulatory compliance, and economic feasibility, this study proposes a practical and timely hybrid retrofit solution for sustainable railway operations, aligning current industry needs with long-term environmental and financial benefits. Full article

Most European Union governments and numerous railway operators have announced plans to replace most of their diesel units by 2030–2040. However, a significant portion of the rail network remains non-electrified. In some cases, the proposed solution has been to close certain tracks, but this approach entails considerable societal costs for small cities and represents a loss of prior railway investments. Consequently, hybrid locomotives and multiple units (either new or refurbished) emerge as a viable solution during this transitional period to enhance energy efficiency and preserve services on these lines, particularly for freight operations. These hybrid units can operate on both electrified and non-electrified tracks and can also serve as “railway prosumers”, contributing to both storage and generation in fully or partially electrified areas. However, implementing these “prosumer tasks” faces challenges, such as the rapid power demand fluctuations during acceleration and the loss of energy recovery potential during braking in hybrid or fully electric units. These losses may also impact the overall power system. This paper presents an alternative approach to modeling double-layer capacitors (supercapacitors) combined with electrical equivalent models for lithium-ion batteries. The Differential Transformation Method (DTM) is used to solve the non-linear ordinary differential equations governing the supercapacitor model, while parameter optimization is achieved through a grid search approach, demonstrating high accuracy compared with laboratory trials. This framework highlights the potential of hybrid units, as illustrated through simulations that analyze storage sizing, energy management, increased energy recovery, and changes in unit performance. These models facilitate a pre-feasibility evaluation of energy storage systems for hybrid railway applications. Full article

Dar es Salaam Port, a crucial logistical hub in East Africa, faces significant challenges related to cargo handling efficiency, road congestion, and capacity constraints. The port’s performance is pivotal for regional trade, necessitating a comprehensive analysis to identify and address operational inefficiencies. This study employed Markov processes to evaluate cargo handling and delivery times, cellular automata for simulating road traffic dynamics, and max-flow models to optimize cargo flow from the port to hinterland destinations. The analysis incorporated factors such as road and rail capacities, traffic conditions, and environmental impacts. The Markov process model indicated that cargo spends 15% of its time waiting at the port, 50% in transit, and 10% delayed, with only 25% successfully delivered. The Cellular Automata simulation revealed severe congestion for heavy trucks due to poor road conditions, with an additional 10 min delay during the rainy season. The max-flow model highlighted that while the road and rail networks generally meet demand, significant bottlenecks exist, particularly for Lubumbashi, which faces a capacity shortfall of 500 t/day. The findings offer actionable insights for stakeholders. Logistics operators can leverage the framework to predict delays, optimize resource allocation, and improve delivery reliability. Policymakers can prioritize strategic investments in infrastructure upgrades, traffic management, and road maintenance to reduce delays and congestion. Scholars can adopt the integrated methodology to analyze similar systems. Together, these efforts can enhance Dar es Salaam Port’s operational efficiency, reduce transit times, and support regional trade development.. Full article

To effectively and objectively evaluate the spatial efficiency of rail transit station areas, seventeen typical rail station areas in Xi’an were selected as the research object. An evaluation system for spatial efficiency was constructed based on data from field research, satellite images, Baidu heat maps, and station passenger flow statistics. Key factors such as land use, transportation systems, social aspects, and spatial efficiency are considered in the framework. A data envelopment analysis (DEA) method was used to evaluate the spatial efficiency of these sample station areas. The results are as follows. ① An incomplete symmetric relationship exists between the Constant Returns to Scale Technical Efficiency (Crste) and the Variable Returns to Scale Technical Efficiency (Vrste) of station area spatial efficiency. The keys to improving station area spatial efficiency include reducing redundant resource investments and establishing a rational resource allocation structure. ② For high-efficiency station areas, the Crste and Vrste are relatively high, with an overall increasing return to scale efficiency (Scale). In medium-efficiency station areas, the Crste is relatively high, but either Vrste or Scale is low. In low-efficiency station areas, the Crste is moderate, and both Vrste and Scale are low. The findings provide a reference for the intensive use of land around Xi’an rail stations, as well as support for the sustainable operation of rail transit. Full article

The Rurality Index is an important reference for the formulation of rural development strategies and policies, but the evaluation of the rurality of megacities based on the township scale is relatively limited. Based on the perspective of spatial governance, this study constructed the evaluation index system of Shanghai’s rurality and carried out the evaluation of Shanghai’s rurality at the township scale from 2005 to 2020. The article adopts the MGWR model to analyze the driving effects of five key driving factors (the proportion of foreign population, per capita industrial output value, public finance revenue, social fixed asset investment, and rail transit coverage), and adopts the Geo-Detector model to analyze the interactive driving effects of two factors. The results indicate that the rurality index of megacities and townships as a whole shows a weakening trend, and the above factors have a predominantly negative impact on rurality, with differences in the intensity of the impact in different periods. There is an obvious interactive additive effect between the factors. When formulating policies for township development, government departments need to take into account the functional positioning of the region and comprehensively adopt targeted policies on population, industry, transportation, finance and investment to regulate and guide the transformation or sustainable development of the countryside. Full article

The original meaning of city–industry integration should be understood as the coordination, balance, reasonable layout, and mutual support between urban production functional areas and service functional areas, which both have urban populations as their core element. The evaluation of city–industry integration in industrial parks can be carried out from two aspects: land–industry integration and residence–industry integration. The secondary indexes of the former mainly include industrial land efficiency and service sector land efficiency, while the secondary indicators of the latter mainly include supporting rail transit and the matching degree between residence and environment. The output value, land use structure, enterprise profile, employment rates, investments, air quality, rail transit system and other data points regarding sample industrial parks were collected by means of geofencing as well as through the creation of an enterprise credit information database and development area yearbook. The Analytic Hierarchy Process (AHP) combined with expert scoring was used to determine the index weights and implement the evaluation of city–industry integration. This study found that city–industry integration in Beijing and the Chengdu Economic and Technological Development Zones is at the forefront of sample industrial parks, and the entropy weight evaluation method verified this evaluation result. The analysis of the benchmark development zone of city–industry integration shows that the Chengdu model and the Beijing model are worthy of reference for growing and mature industrial parks when promoting city–industry integration. Full article

Population and tourism growth has increased congestion, collisions, climate harming emissions, and transport inequities in the Okanagan Valley, British Columbia (B.C.), Canada. Surveys indicate a willingness among residents to switch from cars to public transit featuring better service levels and connections. We conducted an analysis on the economic feasibility of an Okanagan Valley Electric Regional Passenger Rail (OVER PR) powered by zero-emission (ZE) Fuel Cell/Battery Hybrid Rail (Hydrail) technology along a 342-km route between Osoyoos, B.C., at the US Border and Kamloops, B.C., the Canadian VIA rail hub. Hydrail passenger light-rail has operated successfully since 2018 in Germany and was demonstrated in Quebec, Canada, in 2023. Technical analyses have confirmed the feasibility in B.C. on steep Highway (Hwy) 97 grades and mountainous weather, with mode shift forecasts in the range of 30%. OVER PR economic analyses were also favorable, with net present value (NPV) = CAD 40 billion (CDN, base year 2023), benefit–cost ratio (BCR) = 9:1, and Return on Investments (IRR) = 33% over 30 years. Subject to additional stakeholder consultations and final design reviews, these results were tested against risks using Monte Carlo Simulation (MCS) and Reference-Class Forecasting (RCF), including worst-case risks such as 70% cost over-runs. OVER PR promises an economic transition to clean energy, sustainable transportation, and more livable communities, benefiting all Valley communities through greater transportation equity. Full article

This paper presents a novel theoretical framework for incorporating climate risks and adaptation investments into infrastructure debt pricing. Utilizing the Capital Asset Pricing Model (CAPM), the framework extends the conventional modeling of infrastructure project revenues and costs to include climate risk considerations. It proposes three climate-informed revenue and cost formulations: adjustmentment of mean and standard deviation, incorporation of extreme climate events via Pareto and Poisson distributions, and a climate-informed cost model that includes adaptation investment. The paper demonstrates the application of this model in pricing a loan for a Light Rail Transit project in Costa Rica, introducing the concepts of “flood risk premium” and “adaptation curves”. This study not only offers a novel lens through which to view infrastructure investment under climate uncertainty but also sets the stage for transformative policy and practice in financial risk assessment, encouraging a shift towards more sustainable and resilient infrastructure development. Full article

Public–private partnership (PPP) projects have the features of extended investment cycles, diminished returns, and high demand for technology. Inadequate utilization of these projects may result in an accumulation of new implicit debt for the government. Consequently, it becomes imperative for the government to manage and mitigate implicit debt risks associated with urban rail transit PPP projects, which is a crucial prerequisite for ensuring the progression of such projects and the unhindered functioning of the financial system. The objective of this study is to investigate the factors that influence government implicit debt risks in urban rail transit PPP projects from the perspective of policy. This study employs the grounded theory method to develop a comprehensive framework model that identifies the influencing factors of government implicit debt risk in urban rail transit public–private partnership (PPP) projects. The contributions of this study are twofold: (1) it highlights the role of policy as a significant determinant of implicit debt risks of urban rail PPP projects, which contain governmental subsidies, external environmental risk sharing, and supporting measures. Specifically, government subsidies directly contribute to the government’s implicit expenses, thereby impacting the level of implicit debt risks associated with urban rail transit PPP projects. Supporting measures exert an indirect influence on the implicit debt risks of the government, thereby imposing a significant burden on local fiscal expenditure. External environmental risk sharing, as an external factor, leads to an increase in fiscal expenditure due to the government’s social responsibility; and (2) it provides a qualitative method that examines the government implicit risk factors associated with urban rail trait PPP projects based on grounded theory. The model that examines the influencing factors of government implicit debt risk in urban rail transit PPP projects adopts a policy perspective, which can inform policymakers on a heretofore unexplored adverse effect of guarantee policy. Full article

The IPCC highlighted the potential for rail transport to play a vital role in transitioning to a low-carbon economy. In many countries, rail networks are operated and maintained by private companies. However, in N.Z., the privatization was undone in 2008. The nationalization was necessary to enable public investments to gain long-term benefits for N.Z. as a whole. Literature shows that accurate life cycle cost analysis of networks is very complex, and benefits are financial, environmental, and social. The latter two categories of benefits are often not considered by private companies. The uncertainties in calculations are often so significant that perhaps a more relevant issue is determining the long-term benefits of a network for a country. Full article

Climate change is the main cause of frequent extreme weather and natural disasters. Therefore, effective climate adaptation strategies for urban rail transit (URT) should be adopted to cope with extreme precipitation events (EPEs). This study proposes a decision-making model based on climate change for drainage renovation, which consists of an optimal renovation sequence model and an optimal investment timing model. This study analyzes the inundation risk of each station and its node importance in the URT network and then uses a multi-attribute decision analysis (MADA) to determine the optimal renovation sequence. This study also uses a real options pricing approach to calculate the value of an option in order to defer the renovation project and determine the optimal investment timing. Then, the Beijing Urban Rail Transit (BURT) is taken as an example to conduct an empirical analysis of the proposed model. Considering the uncertainty of climate change and the complexity of the URT network, the model can obtain the optimal renovation sequence and the investment timing of each station, which is expected to provide a decision-making tool for urban governments to formulate an optimal plan that strengthens the prevention of flooding disasters. Full article

The financial market has a strong influence on supporting the transition to a zero-emission transport system, as this sector requires large investments to implement low-emission technologies and infrastructure and to promote intermodality. This article presents the results obtained from a literature review on the financing mechanisms that have been used in different countries to finance alternatives to decarbonization in rail and inland waterway modes. For this purpose, databases such as Google Scholar, Scopus, MDPI, websites of governments and other related organizations were reviewed. Over 240 sources of information from articles and documents focusing on green finance in rail and inland waterway modes were reviewed. Our study identified many gaps in the literature on green transport financing. We also identified that in the databases consulted, it was possible to obtain more academic sources related to rail transport than inland waterway transport. Finally, an analysis is made of how implementation projects in the rail and inland waterway modes have been financed in Colombia. Full article