Search Results (7)

Green transportation is the core embodiment of ecological civilization and the concept of green development within the field of transportation, and it is an important strategic choice for sustainable urban development. National central cities represent the highest level in China’s urban system planning. This paper aims to evaluate the level of green transportation development in national central cities. It established a set of 29 specific evaluation indicators from five dimensions: basic indicators, green transportation infrastructure, traffic environmental protection, traffic travel, and traffic safety. It constructed an evaluation index system for the development level of green transportation. The entropy weight TOPSIS method was utilized to evaluate the development levels of green transportation in nine national central cities from 2020 to 2022. An obstacle degree model was constructed to identify key obstacle factors at both the criterion and indicator layers of the green transportation development level evaluation index system for national central cities. Suggestions were proposed from five aspects: establishing a comprehensive policy framework, promoting regional collaborative development, accelerating infrastructure construction, improving transportation service quality, and fostering the green upgrading of industries. The results showed that the comprehensive ranking of green transportation development levels among the national central cities from high to low for the years 2020–2022 was as follows: Shanghai, Chongqing, Chengdu, Beijing, Guangzhou, Tianjin, Wuhan, Xi’an, Zhengzhou. In terms of the regional spatial layout, the green transportation development levels of the nine national central cities generally exhibited a “high on the periphery, low in the center” distribution characteristic. The comprehensive ranking of the obstacle degree in the criterion layer was as follows: basic indicators, traffic travel, green transportation infrastructure, traffic environmental protection, traffic safety. After screening the criteria level where the obstacle degree calculation results are above 15%, traffic safety is eliminated. The nine cities, which were located in different regions, generally maintained consistent internal obstacle factors and their order. The top five indicators with the highest frequency of obstacle degrees at the indicator layer were as follows: total passenger transport volume, number of taxis, new energy vehicle production, expenditure for transportation, and total freight transport volume. The specific key obstacle factors at the indicator level were different in the nine cities. Full article

Exergy is a thermodynamic concept that ponders the quality of energy. It evaluates the irreversibilities of a machine, demonstrating its capacity to perform work associated with energy conversion. This article focuses on directing public policies and vehicle development toward their most proper usage worldwide. In the urban mobility scenario, there is an obvious demand to decrease greenhouse gas (GHG) emissions. In addition, the internal combustion engine (ICE) experiences considerable energy losses through heat exchange through the radiator and exhaust flow gases, which are not considerable in battery electric vehicles (BEVs) since there are no exhaust gases subsequent to combustion, nor combustion itself. This work presents longitudinal dynamics simulations of passenger vehicles to understand the magnitude of exergy destruction in ICEVs and BEVs, considering the Brazilian and European Union electric energy mix. Overall, the method can be applied to any other country. The simulation and model parameters were configured to match production road vehicles commercialized in the Brazilian market based on different versions of the same model. Two vehicle dynamic duty cycles were used, one relating to urban usage and another to highway usage, resulting in an overall exergy efficiency of around 50–51% for BEVs considering the exergy destruction in power plants. In contrast, ICE has an average efficiency of 20% in the urban cycle and around 30% in the highway cycle. By comparing the overall equivalent CO₂ emissions, it is possible to conclude that EVs in the European energy matrix produce more GHG than ICE vehicles running on ethanol in Brazil. Nevertheless, there are increasing uses of coal, natural gas, and oil thermal electric power plants, raising the question of how the transition may occur with a general increase in electrification since there is an increasing electric expenditure in all sectors of society, and the renewable energy plants may not meet all of the demand. Full article

Timetable optimization for urban subways is aimed at improving the transportation service. In congested subway systems, the effects of crowding at stations and inside the vehicles have not been properly addressed in timetabling. Moreover, it is difficult to show the time of values in different riding conditions. In this paper, we consider the passenger-travel process as a physical activity expending energy and formulate a travel energy expenditure function for a heavily congested urban subway corridor. A timetable optimization model is proposed to minimize the total energy expenditure, including waiting on the platform and travelling in the vehicle. We develop a heuristic generic algorithm to solve the optimization problem through a special binary coding method. The model is applied to the Yi-zhuang line in the Beijing subway system to obtain a passenger-oriented energy-minimizing timetable. Compared with using the existing timetable, we find a 20% reduction in average energy expenditure per passenger and a RMB 47,500 increase in social profits as the result of the timetable optimization. Full article

The purpose of the paper is to analyse the relationship between digitalisation of public services (e-government) and ESG factors (environmental, social and economic factors). As public administration is a major stakeholder influencing sustainable development and state governments are aiming to digitise their services, there is a need to better understand the effect of the digital revolution on ESG. This article aims to study the relationship between the E-Government Development Index (EGDI) and ESG factors in 26 European countries. The linear ordering method TOPSIS (Technique for Order Preference by Similarity to Ideal Solution) was used for the study, followed by the Perkal index and the method of optimal predictors’ selection—the Hellwig method. The study is based on the Eurostat data (in the period 2003–2020), and the analysis includes ten variables: Share of environmental taxes in GDP; Exposure to dust air pollution; Greenhouse gas emissions by source sector—carbon dioxide, methane, nitrous oxide, etc. (energy, industry, agriculture, forestry, waste management) (thousands of tonnes); Passenger transport volume in relation to GDP; At risk of poverty or social exclusion; Percentage of people satisfied with their financial situation among people aged 16+; Share of the ICT sector in GDP; Unemployment rate of people aged 20–64; Research and development expenditure in all sectors; GDP per capita. The in-depth analysis offers a matrix that represents the relationships between environmental taxes and the development of e-government. The main finding reveals statistically significant relationships between the EGDI and aggregate variables representing the environmental, social and economic spheres. It indicates a genuine, positive impact of digitalised administrative processes on sustainable development. It also seems to confirm that investments in digital infrastructure and government e-services bring multiple long-term benefits and contribute directly to all three domains relevant to the sustainability of modern development. The results of the analysis can be found useful by governments and governmental institutions as informing digitalisation strategies aimed at balancing the development of e-services and their support infrastructure. Nowadays, when planning strategic actions, one should take into account the social, economic and environmental impact of the digitalisation processes. Full article

Traffic carbon emissions have a non-negligible impact on global climate change. Effective estimation and control of carbon emissions from tourism transport will contribute to the reduction in the amount of global carbon emissions. Based on the panel data of Dunhuang in western China from 2010 to 2019, the process analysis method was used to estimate the carbon emissions from tourism traffic of Dunhuang. By establishing the Kaya identity of tourism traffic carbon emissions, the LMDI decomposition method was used to reveal the contribution of different factors to the change in tourism traffic carbon emissions. The results showed that the impact of tourism traffic carbon emissions was diversified; we found three main factors of promoting carbon emissions, namely the number of tourists, tourism expenditure per capita, and energy consumption per unit of passenger turnover. However, the contribution of tourism activities to GDP, passenger turnover per unit of GDP, and energy structure largely inhibited the increase in carbon emissions. Full article

An increase in energy-efficient transportation is one way that cities try to mitigate climate change. In coastal cities, public water transit is also undergoing transitions. A small zero-emission autonomous ferry seems to be a cutting-edge technology in this field. This study aims to decrease the knowledge gap in research on the impacts of autonomous passenger ferry development on urban mobility. In particular, the central theme regards the extent to which the new transport solution can help improve sustainable mobility patterns. This study explores the local spatial context of ferry development, land-use patterns, and transport network structure, and moderates the shift in urban mobility practices. Regarding land use patterns, the case of the coastal city of Gdańsk has been documented in secondary qualitative and quantitative data, including in a large body of policy documents, accompanying expert opinions, and scholarly literature. This study strongly emphasises that a typical short river crossing, due to autonomous vessels, can regain a competitive position, which was partially lost due to linear routes along the river. The research identified crucial benefits of autonomous ferry shipping on urban mobility by increasing public transport network connectivity, reducing travel distance, and creating modal shifts towards foot travel and bike riding. It appears as an exciting scalable solution for cities where limited or dispersed demand prevents achievement of economies of scale, therefore diminishing the necessary expenditures. Full article

Today the world’s largest cruise ships can take on board more than 6000 passengers and almost 3000 crew members. Managing a significant number of people and all equipment and operations on ships requires the delivery of tens of thousands of kilowatts, which poses a huge challenge for both cruise ship builders and ports supporting these ships as well as for ship owners themselves, as the costs involved represent the largest share in the structure of expenditure in cruise shipping companies. In recent years, various communities and institutions, including the International Maritime Organisation and the European Union, exert pressure on cruise ship owners to use green renewable energy solutions. For these reasons, cruise ship owners are constantly looking for cost-effective and environmentally responsible solutions regarding new energy sources for ships. The aim of this paper is to identify modern solutions applied on cruise ships in the field of energy generation and to indicate benefits for the environment and ship owners in this respect. The following research questions were formulated: (1) What factors force cruise ship owners to introduce modern energy policy solutions? (2) What kind of green energy solutions are currently used on cruise ships? (3) What kind of renewable energy solutions do cruise ship owners use to reduce energy consumption on board cruise ships? The research was conducted by applying a few research methods, i.e., desk research method and exploration method, critical and comparative analysis, and also inductive and deductive reasoning. The results of this research can provide an interesting source of information for cruise ship owners, cruise seaport authorities, and shipyards involved in the construction of new vessels. Full article