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Recently, a new shared micromobility service has become popular in cities. The service is supplied by a new vehicle, the e-scooter, which is equipped with a dockless security system and electric power assistance. The relatively unregulated proliferation of these systems driven by the private sector has resulted in numerous research questions about their repercussions. This paper reviews scientific publications as well as evaluation reports and other technical documents from around the world to provide insights about these issues. In particular, we focus on mobility, consumer perception and environment. Based on this review, we observe several knowledge needs in different directions: deeper comprehension of use patterns, their function in the whole transport system, and appropriate policies, designs and operations for competitive and sustainable shared e-scooter services.

The COVID-19 pandemic had a significant impact on container transportation. Accurate forecasting of container throughput is critical for policymakers and port authorities, especially in the context of the anomalous events of the COVID-19 pandemic. In this paper, we firstly proposed hybrid models for univariate time series forecasting to enhance prediction accuracy while eliminating the nonlinearity and multivariate limitations. Next, we compared the forecasting accuracy of different models with various training dataset extensions and forecasting horizons. Finally, we analysed the impact of the COVID-19 pandemic on container throughput forecasting and container transportation. An empirical analysis of container throughputs in the Yangtze River Delta region was performed for illustration and verification purposes. Error metrics analysis suggests that SARIMA-LSTM2 and SARIMA-SVR2 (configuration 2) have the best performance compared to other models and they can better predict the container traffic in the context of anomalous events such as the COVID-19 pandemic. The results also reveal that, with an increase in the training dataset extensions, the accuracy of the models is improved, particularly in comparison with standard statistical models (i.e. SARIMA model). An accurate prediction can help strategic management and policymakers to better respond to the negative impact of the COVID-19 pandemic.

Historical time-series data of container traffic in ports are characterised by strong randomness that causes the time-series prediction performance to vary significantly. In this sense, the prediction accuracy differs as a function of exogenous variables related to port characteristics and the maritime shipping context. Thus, the measuring problem of a priori container traffic predictability (i.e., the ability of methods to predict port traffic variables) arises. Academia suggests that this predictability may be related to entropy as a measure of the information provided. This paper analyses the Sample Entropy (SampEn), as an indicator of the complexity represented by the container traffic time-series data, comparing it with the error metrics provided by a statistical prediction and an artificial intelligent method. The Autoregressive Integrated Moving Average (ARIMA) and Back Propagation (BP) Neural Network are used to obtain the prediction performance of container port traffic in a data set composed of 20 Chinese ports and 5 selected international ports. Unexpectedly, the results indicate that the correlation between the SampEn and the prediction performance of the time series is weak. The complex ecosystem of the container shipping sector and the different port characteristics are suggested as the cause of this poor correspondence. Our findings help to understand the relationship between entropy and the predictability of time-series data in a sector (i.e. port traffic), which has not been explored before. The authors would like to thank the anonymous referees for their helpful comments on this paper. Their comments significantly increased the quality of this paper. We sincerely thank Prof. Zhongzhen Yang from the Faculty of Maritime and Transportation at Ningbo University and Prof. Jose A. Sanchez-Espigares from the Department of Statistics and Operation Research at Universitat Politècnica de Catalunya (UPC-Barcelona Tech) for their valuable suggestions on the revision of this paper. This work was sponsored by K.C. Wong Magna Fund in Ningbo University, China and 111 Project [grant number D21013] and the General Public Welfare Project of Zhejiang Science and Technology Department, China [grant number 2018LGF18E090005].

Water quality and pollution is the main environmental concern for ports and adjacent coastal waters. Therefore, the development of Port Environmental Management systems often relies on water pollution monitoring. Computer vision is a powerful and versatile tool for an exhaustive and systematic monitoring task. An investigation has been conducted at the Port of Palma de Mallorca (Spain) to assess the feasibility and evaluate the main opportunities and difficulties of the implementation of water pollution monitoring based on computer vision. Experiments on surface slicks and marine litter identification based on random image sets have been conducted. The reliability and development requirements of the method have been evaluated, concluding that computer vision is suitable for these monitoring tasks. Several computer vision techniques based on convolutional neural networks were assessed, finding that Image Classification is the most adequate for marine pollution monitoring tasks due to its high accuracy rates and low training requirements. Image set size for initial training and the possibility to improve accuracy through retraining with increased image sets were considered due to the difficulty in obtaining port spill images. Thus, we have found that progressive implementation can not only offer functional monitoring systems in a shorter time frame but also reduce the total development cost for a system with the same accuracy level. This work is supported by ECOBAYS project (MCIN/AEI/10.13039/501100011033) funded from the Agencia Española de Investigación (Spanish Research Agency).

Autonomous vehicles (AVs) are becoming a reality and may integrate with existing public transport systems to enable the new generation of autonomous public transport. It is vital to understand what are the alternatives for AV integration from different angles such as costs, emissions, and transport performance. With the aim to support AV integration in public transport, this paper takes a typical European city as a case study for analyzing the impacts of different AV integration alternatives. A transport planning model considering AVs is developed and implemented, with a methodology to estimate the costs of the transport network. Traffic simulations are conducted to derive key variables related to AVs. An optimization process is introduced for identifying the optimal network configuration based on a given AV integration strategy, followed by the design of different AV integration scenarios, simulation, and analyses. With the proposed method, a case study is done for the city of Uppsala with presentation of detailed cost results together with key traffic statistics such as mode share. The results show that integrating AVs into public transport does not necessarily improve the overall cost efficiency. Based on the results and considering the long transition period to fully autonomous vehicles, it is recommended that public transport should consider a gradual introduction of AVs with more detailed analysis on different combination and integration alternatives of bus services and AVs.

La mobilitat, entesa com el conjunt de viatges en un territori, és una característica inherent a la naturalesa humana. Des de l’origen dels temps, totes les societats han volgut moure’s i viatjar, bé per trobar un lloc millor per viure-hi, per guanyar-se el pa, o per conèixer altres comunitats i relacionar-s’hi. L’adveniment de les tecnologies de la informació i de les comunicacions pronosticava la fi dels viatges. Res més lluny de la realitat. Pot ser que canviïn els patrons i els motius dels viatges, però les persones continuem i continuarem movent-nos.

We describe the implementation of a comprehensive software for Ship Weather Routing referred to as SIM- ROUTE. The A* pathfinding algorithm is used to optimize the sailing route as a function of the wave action. The aim of the software is to provide a comprehensive, open and easy tool including pre- and post-processing for ship weather routing simulations. The software is constructed considering the Copernicus Marine Environment Monitoring Service (CMEMS) wave predictions systems which are available for free use. The code provides the optimized route and the minimum distance route together with additional modules to compute ship emission and safety on navigation monitoring. SIMROUTE has been tested in several cases using different CMEMS products over short and long distances. The comprehensive structure of the code enables it to be easily modified to include additional ship wave resistance models and the effect of the water currents and winds on navigation. SIMROUTE is also used for academic purposes, providing skills for ship routing optimization in the framework of standards of training, certification and watchkeeping (STCW) for competence-based maritime education and training. Due to the simplicity of its use, SIMROUTE is a good candidate for benchmarking strategies and inter-comparison exercises with advanced methods for ship weather routing. This contribution highlights the technical aspects, code organization and structure behind SIMROUTE, demonstrating its capabilities through examples of route optimization.

Barcelona (Spain) had a total population of 1,636,762 in 2019 that are distributed on 10 districts across the city. These districts have different characteristics in size and population density. As a result, this can lead to different traffic crashes injuries occurrences and numbers in these areas. Therefore, this study is attempting to determine the conditional probabilities for each district in order to identify the district that has highest number of injuries compared to other areas. A Bayesian network approach is utilized to analyze the dataset and identify the high-risk district alongside analyzing the varieties of traffic crashes during four-year intervals. The results have shown that the district that has the highest population, highest usage of private transport mode, and highest density of passenger cars per km2 (compared to all other districts), has the highest risk of having all types of injuries resulting from traffic crashes. For the temporal factor represented by the four years interval, traffic crashes occurrences varied from district to district based on the level of injury.

The ship's routing was adopted to organise marine traffic flow and reduce the risk of collision between ships in crowded waters. With the expansion of the world's fleet, ship traffic in shipping bottleneck and chokepoint areas became more and more busy and complex creating serious challenges for navigational safety. Therefore, quantitative collision risk assessment is significantly important for the ships' routeing waters. In this paper, the information entropy method which integrates the K-means clustering based on Automatic Identification System (AIS) data is introduced to quantitatively evaluate the collision risks in the ships' routeing waters. As a case study, the information entropy of Courses Over Ground (COG) for Ningbo-Zhoushan Port (the largest port in the world since 2009) is calculated by using historical AIS data. Then the K-means clustering is used to group the bytes of information entropy of the different legs in the shipping route. We find that in Ningbo-Zhoushan port Precautionary Area (PA) 2, 4 and 7 are the highest risk legs; PA 1, 5 and 6, Traffic Separation Scheme (TSS) 16, and 17 are medium-high risk areas. Therefore, ship collision risk prevention measures should be prioritised in those legs. Our contributions provide a novel approach to quantitatively assess ship collision risks in busy waters.

Trabajo presentado en: R-Evolucionando el transporte, XIV Congreso de Ingeniería del Transporte (CIT 2021), realizado en modalidad online los días 6, 7 y 8 de julio de 2021, organizado por la Universidad de Burgos, A platoon can be defined as a group of consecutive vehicles that exchange information, so that they drive in a coordinated way, allowing very small spacings and still travelling at relatively high speeds. The concept of vehicle platooning is not new. In fact, scientific articles on platooning were published as early as the 1970s, and the first large-scale pilot test on platooning was carried out at the end of the 1990s. The main purpose of these early research works was to improve traffic efficiency and reduce consumptions, as well as to develop the existing technology. These contributions were very valuable, although somehow limited by the relevant technology still being in its infancy. Precisely, the development of technology and communications in the last years has given new impetus to research on vehicle platooning on freeways as one of the possible forms of cooperation among connected automated vehicles (CAVs). The point of view of these recent studies has also been extended: in addition to traffic efficiency, the role of platooning is analyzed in terms of safety, sustainability, business productivity, etc. In this context, there are today many scientific publications on vehicle platooning with different purposes, set in distinct scenarios and based on diverse vehicles and technologies (regular or segregated lanes, cars or trucks, vehicles with different SAE levels, etc.). In order to organize and consolidate the existing knowledge, a comprehensive and systematic review must be performed. This work represents a first approximation to this more ambitious objective. Firstly, platooning has been conceptualized in order to facilitate its analysis and comparisons among studies. Secondly, key publications on platooning have been analyzed to determine the most significant impacts expected from its implementation. Finally, some important research gaps and disparate findings on the topic have been identified., This research has been partially funded by the Spanish Ministry of Economy, Industry and Competitiveness, within the National Programme for Research Aimed at the Challenges of Society (grant ref. PID2019-105331RB-I00).

Trabajo presentado en: R-Evolucionando el transporte, XIV Congreso de Ingeniería del Transporte (CIT 2021), realizado en modalidad online los días 6, 7 y 8 de julio de 2021, organizado por la Universidad de Burgos, Congestion is still a big challenge for urban mobility while vehicle sharing, eCommerce and autonomous vehicles will likely increase the unit veh-km of each vehicle and the density of vehicles moving on the streets. Urban vehicle congestion pricing schemes have been taken as effective solutions to this problem. This paper first reviews the research and application cases of urban congestion pricing through recent years, although with the well-developed theoretical basis and successful practices in Singapore, London, Stockholm, Milan, etc., public acceptance and equity concerns are still the main issues for such policies’ implementation. To circumvent this shortcomings of congestion pricing, a scheme of tradable mobility credits is proposed as an alternative. As travellers are distributed mobility credits within a specific urban area, which are allowed to be traded, those with low vehicleusing demands can sell their credits to those with more demands. Therefore with this scheme, people have the incentive to reduce the using of vehicles. This paper reviews the studies on this new urban mobility management strategy and compared it with ordinary congestion pricing schemes. Finally, we conclude the gap and possible directions for future work in this area., The first author is funded by the Joint Scholarship of China Scholarship Council and Universitat Politècnica de Catalunya.

Santiago, the capital city of Chile, has seven million inhabitants in an area of 850 km2. This city has a metro network with seven lines extending 140 kilometers and transports approximately 2.6 million people daily. The bus system has undergone significant transformations over the last three decades. The most relevant change having been Transantiago, the public transportation system implemented in 2007 for Santiago, Child, which combines the use of Metro and buses (BRT). Metropolitan Mobility Network (called Red) is the latest version of the public transportation plan. This paper aims to analyze the current subway infrastructure using the continuous approximation method for Santiago, Chile. We previously proposed a macroscopic methodology to identify the needs for an adequate level of service in urban mobility and transportation, and we applied it to Santiago’s Metro network. Our work focuses on functionality and demand distribution. Santiago’s demand varies spatially in volume and extension throughout the city. Using the latest origin-destination survey from 2012, we deduct the critical components in this current network structure. It is worth mentioning that the Metro design bases its network on a ring-radial structure. With our macroscopic model applied to Santiago, Chile, we have detected infrastructure needs in the current transit network. The supply of infrastructure should increase for two reasons: first, to achieve balanced cost levels between users and the agency and second, to reduce subway occupations. The optimal model outcomes for Santiago define the optimal network in which the system requires five rings and ten end-to-end longitudinal lines (20 radial routes), including lower levels of occupation. The obtained results are a good preliminary solution, considering the subway infrastructure supply could be sub-estimated in the public transportation plan. The authors had support from the Barcelona Innovative Transportation (BIT) Research Group. Moreover, the first author's work was supported by Chile's National Agency for Research and Development (ANID) / Becas-Chile Doctoral Scholarship Program No. 72160291. The first author had support from the Project 092112MT of the DICYT of the University of Santiago of Chile (USACH).

Trabajo presentado en: R-Evolucionando el transporte, XIV Congreso de Ingeniería del Transporte (CIT 2021), realizado en modalidad online los días 6, 7 y 8 de julio de 2021, organizado por la Universidad de Burgos, People face different barriers when choosing to commute by bike. The predominance of these barriers in users’ perception could explain the low cyclability rates present in many cities. An investigation of cyclists’ perceptions is developed using the data set obtained through a survey made to individuals from Quito, Ecuador. This study is aimed to evaluate the perception of a group of individuals about barriers to bike use, in particular, assesses how perception varies according to the available information and the different profiles. Using ordered probit models, the study compares the overall evaluation of bike acceptance before and after making individuals reflect on the importance of certain variables (e. g. lack of bike infrastructure, city temperatures, etc.). The main results show that to improve bike use acceptance, enhancing multimodality or providing facilities like electric bikes must be considered. The results also demonstrated a high heterogeneity of individuals’ perceptions caused by their socio-demographic characteristics and the environmental context., This research was partially funded by the Universitat Politècnica de Catalunya (UPC).

Trabajo presentado en: R-Evolucionando el transporte, XIV Congreso de Ingeniería del Transporte (CIT 2021), realizado en modalidad online los días 6, 7 y 8 de julio de 2021, organizado por la Universidad de Burgos, E-commerce sales worldwide are expected to skyrocket in future years, increasing freight traffic in cities. In this context, sidewalk autonomous delivery devices (ADDs) show great potentialities to decrease carriers’ last-mile operation costs. Nevertheless, the implementation of these autonomous robots requires some adjustments in the supply chain because of their particular characteristics. To avoid severe accidents with pedestrians, their speed and size will be limited and, as a consequence, ADDs seem more adapted to the delivery of small items. The objective of this paper is to estimate the carrier’s total operation costs in a dual delivery channel. If its size is lower than a given threshold, the parcel is delivered to the customer through a supply chain compound of a logistics micro-hub and ADDs. Otherwise, if the parcel is bigger than the given threshold, it is delivered through a business-as-usual supply chain with delivery vans. The carrier’s total operation costs is the sum of the costs induced by the two distribution channels. Assuming that the parcel size follows a known probability distribution function, the carrier’s total operation costs are estimated using the continuous approximation methodology. Different probability distribution functions modelling the size of the parcels are studied in the paper. Finally, the dual distribution channel is optimized considering the size threshold as a decision variable of the system., The first author would like to personally acknowledge CARNET Barcelona for the funding of this research article, developed in the framework of his PhD thesis.

Ship-related marine oil spills pose a significant threat to the environment, and while it may not be possible to prevent such incidents entirely, effective clean-up efforts can minimize their impact on the environment. The success of these clean-up efforts is influenced by various factors, including accident-related factors such as the type of accident, location, and environmental weather conditions, as well as emergency response-related factors such as available resources and response actions. To improve targeted and effective responses to oil spills resulting from ship accidents and enhance oil spill emergency response methods, it is essential to understand the factors that affect their effectiveness. In this study, a data-driven Bayesian network (TAN) analysis approach was used with data from the U.S. Coast Guard (USCG) to identify the key accident-related factors that impact oil spill clean-up performance. The analysis found that the amount of discharge, severity, and the location of the accident are the most critical factors affecting the clean-up ratio. These findings are significant for emergency management and planning oil spill clean-up efforts.

Cycling constitutes a clean, healthy, and low-cost mode of transport. Therefore, the promotion of cycling is currently one of the main goals of administrations around the word. Former studies have shown that safety perception plays a fundamental role in the acceptance of bikes as a habitual mode of transport. In this context, this research aims to determine which variables and actions can give rise to this feeling of safety and, therefore, collaborate in the modal shift towards a more sustainable mobility. For this purpose, different strategies have been developed in two different contexts, Helsinki and Barcelona, using two different methodologies, namely expert interviews and analysis of survey data. Particularly, the methodology of analysis used includes descriptive statistics and path analysis. Results point out that safety perception highly depends on trip purpose, as significant differences are observed for daily users compared to those who cycle for sport reasons. Demographic characteristics (age, gender, etc.) and use patterns are also associated with different perceptions of safety and different behaviors. However, for any cyclist, the quality of the available infrastructure significantly influences his/her safety perception. Thus, the provision of good quality and well-structured cycling infrastructure is the most important initiative to promote cycling. Peer Reviewed Objectius de Desenvolupament Sostenible::11 - Ciutats i Comunitats Sostenibles::11.2 - Per a 2030, proporcionar accés a sistemes de transport segurs, assequibles, accessi­bles i sostenibles per a totes les persones, i millorar la seguretat viària, en particular mitjan­çant l’ampliació del transport públic, amb especial atenció a les necessitats de les persones en situació vulnerable, dones, nenes, nens, persones amb discapacitat i persones grans Objectius de Desenvolupament Sostenible::11 - Ciutats i Comunitats Sostenibles

This paper presents the optimization problem of three different on-demand transit systems operated by vehicles of different sizes. This problem is aimed at minimizing the total cost of the system, which consists of the temporal cost experienced by users and the operating cost incurred by transit agencies. A compact set of estimations of the user performance and operating cost is provided, based on geometric probability. The optimization procedure allows the cost comparison of different semi-flexible services. Transit systems operated by cars (shared taxicabs) with flexible layouts are preferable for low demand densities (less than 92 pax/km2-h). For very high demand (higher than 200 pax/km2-h), bus systems with fixed layout and variable stop locations present the lowest total cost per passenger. In an intermediate domain, taxi and semi-flexible services compete among each other. The estimation of unit operating costs allows decision-makers to calculate the subsidies needed to make the system profitable. The first and last authors thank AMTU (public entity Association of Municipalities with Urban Transportation) that supported this research under the contract C-11523 “Flexitransport” with our University Barcelona TECH. The contribution of the third author has been supported by the Chilean Scientific Research Agency (CONICYT), under the grant PFCHA/BCH No. 72160291. This work was supported by the Chilean Scientific Research Agency (CONICYT), [PFCHA/BCH No. 72160291]; AMTU [C-11523].

This paper explores the factors influencing taxi travel in the context of COVID-19 from both demand and supply sides and provides a quantitative comparison of taxi travel characteristics and taxi industry operations before and after the epidemic. A model was established using system dynamics to simulate a taxi travel system, which was used to analyze the changes in demand and supply of taxi travel under scenarios such as closedowns, travel restrictions, etc. The analysis is based on a typical middle-sized city in China, Ningbo in Zhejiang Province, revealing factors leading to the significant drop in the amount of taxi travel due to the epidemic. The study can provide insights into impacts of public (or similar anomalous or catastrophic) events on taxi travel systems and could be useful for urban transport planning and management.

Traffic accidents are still wide causation for fatalities around the globe. The set of alarm for this cause of deaths is still on, since the number of fatalities is still representing an enormous issue and a challenge for most governments. In Barcelona, similar to the rest of the world, traffic accidents are threatening lives and raising the need to lessen the number of both fatalities and severities. This study is conducted to grasp the correlations between different classification factors with accident severities and fatalities. A total of 47,153 traffic accident cases that occurred between 2016 and 2019 are utilized. Then, a binary probit model and Chi-square automatic interaction detector are exploited to grasp the impact of several risk factors. The results confirmed that males and 65 years and older injured persons are more exposed to severe or fatal injuries compared to other categories. Pedestrians and drivers are found to have higher probabilities compared to passengers in being involved in severe or fatal injuries. Weekends, afternoon, night timings all have higher odds of having severe or fatal traffic accidents. The findings of this study can help road authorities in targeting these risk factors to mitigate their impact to achieve Vision Zero.

As for any other discipline, urban planning can only be considered sustainable if it combines care for the environment with the satisfaction of social needs and economic balance. Given that women make up almost 50% of the world's population, urban planning that neglects women’s needs is not sustainable. Numerous studies show that mobility patterns vary according to gender and are linked to people’s daily activities, which also depend, among others, on the economic and educational level. The other way round, limited mobility opportunities lead to some women’s restricted access to particular activities. This work aims to briefly explain existing inequalities and their potential solutions under different boundary conditions. Objectius de Desenvolupament Sostenible::5 - Igualtat de Gènere Objectius de Desenvolupament Sostenible::5 - Igualtat de Gènere::5.4 - Reconèixer i valorar les cures no remunerades i el treball domèstic no remunerat, mitjançant la prestació de serveis públics, la provisió d’infraestructures i la formulació de polítiques de protecció social, així com mitjançant la promoció de la responsabilitat compartida a la llar i la família, segons escaigui a cada país Objectius de Desenvolupament Sostenible::11 - Ciutats i Comunitats Sostenibles Objectius de Desenvolupament Sostenible::11 - Ciutats i Comunitats Sostenibles::11.2 - Per a 2030, proporcionar accés a sistemes de transport segurs, assequibles, accessi­bles i sostenibles per a totes les persones, i millorar la seguretat viària, en particular mitjan­çant l’ampliació del transport públic, amb especial atenció a les necessitats de les persones en situació vulnerable, dones, nenes, nens, persones amb discapacitat i persones grans Objectius de Desenvolupament Sostenible::5 - Igualtat de Gènere::5.1 - Posar fi a totes les formes de discriminació contra totes les dones i nenes a tot el món

A significant proportion of global carbon dioxide emissions are attributed to ocean-sailing ships and shipping emissions are predicted to double in less than 30 years. This paper investigates the benefit of using weather ship routing optimisation, assessing the ship emissions for minimum distance routes and optimised routes. The present contribution merges the estimation of shipping pollutants and their mitigation through weather routing optimisation; two lines of research widely analysed separately but seldom discussed together. A previously developed open software of weather ship routing is used to obtain the minimum cost (i.e. optimised route) in terms of sailing time, using high-resolution wave forecasting. The assessment of fuel consumption and ship emissions calculations were inspired by the STEAM2 bottom-up approach, in conjunction with the estimation of the power increase needed to overcome speed decrement due to waves. Several scenarios covering the Western Mediterranean Short Sea Shipping routes (from 24 to 600 nautical miles and using a real Ro-Pax vessel) are compared in terms of emissions between the minimum distance route and the optimum. The ship routing optimisation reveals a reduction up to 30% of ship emissions during severe storms on longer routes. Nevertheless, all the cases studied show emissions mitigation when ship routing optimisation is used. The expected increase of extreme weather events, in terms of frequency, intensity and duration due to climate change, suggests a gradual gain of implementing weather ship routing optimisation in all types of routes, regardless of the distance.

Current last-mile logistics operations are inefficient. The economic competitiveness of logistics service providers is affected by distinct factors, such as the limited time windows they are given to deliver freight in increasingly complex urban environments. This paper presents the different challenges that the sector faces to make its operations more sustainable, from both economic and environmental perspectives. Then, an exhaustive list of measures and initiatives is presented and for each of them, the impact on the different agents involved in last-mile operations is analyzed. This study is expected to help understand the relations between the different actors and design compensatory mechanisms between the parties that mostly benefit from the measures and the most affected ones. Finally, a particular focus is set on the technological developments that are expected to shape the evolution of last-mile operations in the medium or long term. As in the passenger mobility industry, digitization, the emergence of more innovative and modular vehicles, and automation are trends that will undoubtedly affect the market. To maximize the impact of these new technologies, balanced and fair governance schemes and compensatory mechanisms between agents should be designed. The authors believe that the EIT Urban Mobility framework is perfectly adequate to improve this required collaboration between all agents. As a first step towards an increased sustainability of last-mile operations, win-win and agreed measures should be implemented to set the ground for more innovative and disruptive solutions that will emerge in future years.

Coastal bays and estuaries with aquaculture activity may show spatial variability on the exposure at river-borne substances such as nutrients, pesticides or pollutants. In function of the relative geographical position of the rafts and the meteo-oceanographic conditions, the rafts affection from freshwater plume may entail substantial differences. This work evaluates the river-borne affection substances in function of the acute and chronic perspectives. We based on the results of a set of a conservative tracer numerical experiment designed to cover a wide range of meteo-oceanographic conditions. The indexes are obtained for a shallow and micro-tidal bay (i.e. Fangar Bay) where the 3-D TELEMAC numerical model is implemented. The numerical model in Fangar Bay is calibrated and verified using “in situ” current meter data, lagrangian buoys and CTD profiles. The exposure assessment helps to understand the spatial-temporal variability of the dynamics within the bay and the conclusions may support the developing of sustainable aquaculture activities. The authors want to acknowledge the Ecosistema-BC Spanish research project (CTM2017-84275-R/MICINN-AEI-FEDER, UE) and ECO-BAYS research project (PID2020-115924RB-I00, financed by MCIN/AEI/10.13039/501100011033)andthe projects “Carrying capacity for shellfish aquaculture in Fangar Bay” ARP029/18/00008 and “Buffer zones in shellfish aquaculture” ARP059/19/00006; both funded by the European Maritime and Fisheries Fund (EMFF) and the Ministry of Climate Action, Food and Rural Agend.

Customer demand is dynamic and changeable; thus, optimality of the enterprise’s initial location cannot be guaranteed throughout the planning period in order to minimize site selection cost and maximize service reliability in the whole operation cycle. The enterprise planning period is divided into different stages, and a static location model is established at the fixed stage. In addition, a multi-stage dynamic location model is established by introducing the transfer cost between adjacent stages. To reduce the difficulty of solving the dynamic location model, first, we determined the optimal site selection and allocation strategy for each stage. Second, we designed a novel method that transforms the multi-stage dynamic location problem into the shortest path problem in graph theory. Finally, the Dijkstra algorithm was used to find the optimal dynamic location sequence so that its cumulative cost was the lowest in the whole planning period. Through a case study in China, we compare the costs of static and dynamic locations and the location cost under different objectives. The results show that this dynamic location generates more income (as it reduces cost) in comparison to the previous static location, and different location objectives have a substantial influence on location results. At the same time, the findings indicate that exploring the problem of enterprise location from a dynamic perspective could help reduce the operating cost and resources from a sustainable development perspective.

This paper analyzes the new operations induced by the energy range limitation in battery electric bus (BEB) systems to ensure the service provision along the whole day. An operating model has been developed to estimate the number of resources to be deployed (extra vehicles and charging facilities) for two charging schemes: charging at bus garage facility and opportunity charging at on-street chargers. Firstly, the model calculates the entrance and exit time of buses in service assuming an unlimited battery capacity, caused by demand and headway variations in different time periods along day. Then, based on the previous results, the model estimates the moment when vehicles will run out of energy and proposes a charging schedule as well as new vehicle movements between chargers, bus garage and routes to maintain the targeted headway. Consequently, the model is able to calculate the number of resources needed and the total cost for a given route and battery size, allowing cost and performance comparison to diesel and hybrid powertrains. The estimated results in two bus routes in Barcelona indicate that the purchasing cost of BEB vehicles (670,000 euros/veh for articulated, 500,000Euros/veh for standard vehicles, both depreciated over a lifetime of 15 years), battery packs (231 Euro/kWh purchased, depreciated over a lifetime of 10 years), as well as the investment in chargers, are still high to clearly justify their cost-competitiveness against diesel or hybrid counterparts. Nevertheless, if the acquisition cost of both vehicles and battery pack are only reduced by 9%, the BEB technology may present cost savings for transit agencies. It only happens if the fleet size is as large as the corresponding to diesel and hybrid technologies. Opportunity charging is resulted to be more cost- efficient than charging at bus garage for small battery packs, routes with acceptable time headway adherence and, specially, when fast chargers are located very close to terminal stops. Nevertheless, when the real bus route design and operation do not fulfill these standards, charging scheme at bus garage is preferable. This research was partly developed within the ZeEUS project framework. ZeEUS was co-funded by the European Commission under the 7th Research and Technological Development Framework Programme (FP7), Directorate-General for Mobility and Transport under grant agreement n°605485. Peer Reviewed Objectius de Desenvolupament Sostenible::13 - Acció per al Clima Objectius de Desenvolupament Sostenible::11 - Ciutats i Comunitats Sostenibles Objectius de Desenvolupament Sostenible::7 - Energia Assequible i No Contaminant

The risk of ship–bridge collisions should be evaluated using advanced models to consider different anti-collision and bridge-protection measures. This study aimed to propose a method to evaluate the effectiveness of active and passive safety measures in preventing ship–bridge collision. A novel ship–bridge collision probability formulation taking into consideration different safety measures was proposed. The model was applied at Jintang Bridge in China where the surrounding vessel traffic is ultra-crowded. We calculated the collision probability between the bridge and passing traffic using automatic identification system (AIS) data, Monte Carlo simulation, and Bayesian networks. Results under four different safety measures (i.e., active measures, passive measures, both measures and none) were analyzed and compared. The analysis concluded that both active and passive safety measures are effective in reducing the ship–bridge collision probability. Active measures, if deployed properly, can provide protection at an equivalent level than passive measures against collision risks. However, passive measures, such as setting arresting cables, are necessary in cases where the response time of the active measures is long. The proposed method and the results obtained from the case study may be useful for robust and systematic effectiveness evaluation of safety measures in other cases worldwide.

This is the accepted version of the following article: [Sala, M, Soriguera, F. Lane‐changing and freeway capacity: A Bayesian inference stochastic model. Comput Aided Civ Inf. 2020; 1– 15. https://doi.org/10.1111/mice.12529], which has been published in final form at https://onlinelibrary.wiley.com/doi/abs/10.1111/mice.12529 This article presents a new stochastic computational model for determining freeway capacity reduction as a result of lane-changing activity. The probability density function for the maximum flow that can be sustained on a freeway for a given lane-changing level is obtained. The results can be used to support freeway management strategies aiming to mitigate the negative consequences of lane-changing in freeway capacity. A pilot test using empirical data obtained from the B-23 freeway accessing the city of Barcelona proves the validity of the modeling approach.

Autonomous vehicles (AV) will be present in freeways, and they will have to share current infrastructure with human driven vehicles. This mixed traffic scenario needs to be planed and managed. Some research points that an AV mismanagement could lead to a capacity decrease. This can be solved with connected AV traveling in platoons. Some research exist to that end, but all of them is done using microsimulation tools. These are very powerful and detailed tools but have the shortcoming of strongly rely on an uncertain calibration and give limited insights to the problem. The more robust and simpler to understand macroscopic tools, have almost no platooning models yet. The research presented in this paper fills the gap, by providing a generalized macroscopic model to estimate the average length in vehicle for platoons. This is done by giving a set of rules for AV to form a platoon, including two different platooning schemes representing the best and worst case scenarios. This is of a key importance as greater platoon length is the main factor to drive capacity improvements on highways, which under the appropriate conditions can exceed 10.000 vehicles per hour and lane. Authors want to acknowledge Frosso Makri that has shared some knowledge on how to compute the average opportunistic platoon mean. Also Marcos Medina and Enrique Jimenez are acknowledged for some useful comments on how to better explain and show some of the results presented in this reasearch. This research has been partially funded by the Spanish Ministry of Economy and Competitiveness (Ministerio de Economía y Competitividad, Gobierno de España), grant number TRA2016-79019-R/COOP.

Trabajo presentado en: R-Evolucionando el transporte, XIV Congreso de Ingeniería del Transporte (CIT 2021), realizado en modalidad online los días 6, 7 y 8 de julio de 2021, organizado por la Universidad de Burgos, The phenomenon of "smart cities" generalizes the use of Information and Communication Technologies. The generation and use of data to manage mobility is a challenge that many cities are betting on and investing in. Through the Internet of all things (IoT) and the use of sensors and mechanisms for capturing information, the number of data analysis tools such as Big Data, Artificial Intelligence (AI), and Augmented Reality (AR) has increased. The tools that are used to interpret events are applied to the analysis of video and photographic images and comprise of a set of programs, mathematical algorithms and protocols. The implementation of procedures could enable the automatic interpretation of image information, from the most basic such as changes in the presence of objects or people, to the identification of complex shapes and relevant event detection. With the constant use of the assisted process learning (Machine Learning), it’s possible to improve event interpretation through the customization of learning protocols. Repetitively trained software can identify relevant events and report changes in critical scenarios that can trigger a series of protocols. The use of artificial intelligence techniques makes it possible to automate monotonous processes and improve transport management. This article analyzes different technologies used to generate transport information and data validation. It is intended to experiment with the use of technologies in the detection of relevant facts, changes of state, and identification of events. It also measures the reliability level when detecting events, and studies the implementation of possible solutions into the transport management system, in order to assist in decision making processes.

Structural analysis in a transit network is a key aspect used to evaluate in a planning process. In this sense, the use of network science was applied in this work to generate a framework of the main structural features of a transport network. In this case, an alternative transport network in Guadalajara, Mexico was taken as an example. The network properties selected were grade of accessibility, spatial friction, and vulnerability. In the case of the grade of accessibility, this propriety makes reference to the efficiency of the travel time that the network gives due to its structural features. The spatial friction measures how direct in terms of distance the trips that the network provides are, and the vulnerability relates to the ease with which the network can comprise its performance by affectations to their nodes or links. In this sense, this work presents a detailed methodology and a set of open-source tools that can be used to measure these key structural elements for decision making. This research was funded by Mexican National Council for Science and Technology (CONACYT), grant number 641618.

This paper evaluates the impact of vehicle automation and electrification on the applicability of fixed routes and door-to-door services to supply a feeder transit solution in suburban areas. These technologies will modify the current cost structure of the bus system depending on how mature they are, reducing operating costs and increasing capital costs. By means of a continuum approximation model, we evaluate the performance for users and agency of the two feeder strategies in different scenarios of technological development. The results show that automation has the main impact on the applicability between the two feeder alternatives while the effects of electrification are considerably smaller. The future applicability of door-to-door trips reaches wider ranges, although this change is especially significant under some circumstances of technology, service area and users. The expansion of this range is relevant in case the automated bus is mature enough (high reduction of operating cost and low vehicle acquisition price), the areas are small, the trips are short and the value of time is high. However, the results reveal that fixed routes will remain a competitive feeder solution in a wide range of scenarios. We identify that the demand density threshold grows sharply in front of any reduction of agency costs once its value is around 200–300 pax/km2-h. Therefore, flexible services will gain applicability especially in environments that allow reaching this threshold. The research was funded by Stockholm County Council (grant no. 20170901), KTH Integrated Research Lab (ITRL) and TRENoP Strategic Research Area.

This is an Accepted Manuscript of an article published by Taylor & Francis Group in Maritime Policy & Management on Published online: 12 Sep 2021, available online at: http://www.tandfonline.com/10.1080/03088839.2021.1972175. The Yangtze River Delta multi-port system (YMPS) receives increasing attention due to its relevance in world trade and excellent competitiveness in the container traffic market. To insight into the development pattern of YMPS, this paper proposes a method that combines the Hierarchical Clustering with compositional data (CoDa) exploratory tools (i.e., biplot and dendrogram) to explore the temporal and spatial evolution of the YMPS from 1992 to 2019. CoDa describes parts of some whole (i.e., frequency and percentage), conveying relative information in the ratios between its components. Container traffic share in a multi-port region is typical CoDa. Traditional statistical approaches to CoDa could lead to spurious correlations and erroneous conclusions. However, using suitable CoDa techniques, such as the centered log-ratio (clr) transformation, can effectively avoid these misinterpretations. The novel method can simultaneously find the temporal and spatial characteristics. The findings indicate that the development of the YMPS has gone through four stages and the evolution of the YMPS is characterized by a tendency towards a ‘multi-core development’ and faces a differentiated pattern of ‘peripheral port challenges’. The analysis further improves the port system’s evolutionary model and explains the underlying reason for the YMPS development. CoDa techniques also provide a new perspective for the temporal and spatial evolution of the transport discipline. This work was supported by the Ministerio de Ciencia, Innovación y Universidades under project Methods for Compositional analysis of Data (CODAMET) [grant number RTI2018-095518-B-C22, 2019-2021] and 111 Project [grant number D21013]

The investment environment in port infrastructure appeared fluctuating in recent years, which threw more uncertainties and challenges in port Public-Private Partnership (PPP). Among ports in PPP, Dandong Port is the first case for port bankruptcy in China. In this contribution, the Interpretative Structural Model (ISM) is employed to investigate why the bankruptcy of Dandong Port happened and analyze the causes from different perspectives. The ISM-based model interprets the interrelationships among those causes and their positions in the structural hierarchy from high- to low-level. Results reveal that: (i) these factors ( i.e. the economy slowing down in the hinterland, ambitious port plan of local government and unprofessional top management) were the most direct factors to Dandong Port’s bankruptcy; (ii) these factors ( i.e. the economy slowing down in the hinterland, ambitious port plan of local government and unprofessional top management) were the most fundamental causes to this failure; (iii) these factors ( i.e. the ambitious port plan of local government, inappropriate strategic positioning, continuous expansion in port investment and unprofessional top management) were the most core causes for this collapse. Findings provide lessons to be learned from the bankruptcy for port PPP and offer managerial insight into port management policy.

Trabajo presentado en: R-Evolucionando el transporte, XIV Congreso de Ingeniería del Transporte (CIT 2021), realizado en modalidad online los días 6, 7 y 8 de julio de 2021, organizado por la Universidad de Burgos, Santiago, the capital city of Chile, has seven million inhabitants in an area of 850 km2. This city has a metro network with seven lines extending 140 kilometers and transports approximately 2.6 million people daily. The bus system has undergone significant transformations over the last three decades. The most relevant change having been Transantiago, the public transportation system implemented in 2007 for Santiago, Child, which combines the use of Metro and buses (BRT). Metropolitan Mobility Network (called Red) is the latest version of the public transportation plan. This paper aims to analyze the current subway infrastructure using the continuous approximation method for Santiago, Chile. We previously proposed a macroscopic methodology to identify the needs for an adequate level of service in urban mobility and transportation, and we applied it to Santiago's Metro network. Our work focuses on functionality and demand distribution. Santiago's demand varies spatially in volume and extension throughout the city. Using the latest origin-destination survey from 2012, we deduct the critical components in this current network structure. It is worth mentioning that the metro design bases its network on a ring-radial structure. With our macroscopic model applied to Santiago, Chile, we have detected infrastructure needs in the current transit network. The supply of infrastructure should increase for two reasons: first, to achieve balanced cost levels between users and the agency and second, to reduce subway occupations. The optimal model outcomes for Santiago define the optimal network in which the system requires five rings and ten end-to-end longitudinal lines (20 radial routes), including lower levels of occupation. The obtained results are a good preliminary solution, considering the subway infrastructure supply could be sub-estimated in the public transportation plan., The authors had support from the Barcelona Innovative Transportation (BIT) Research Group. Moreover, the first author's work was supported by Chile's National Agency for Research and Development (ANID) / Becas-Chile Doctoral Scholarship Program No. 72160291. The first author had support from the Project 092112MT of the Departamento de Investigaciones Científicas y Tecnológicas (DICYT) of the University of Santiago of Chile (USACH).

Trabajo presentado en: R-Evolucionando el transporte, XIV Congreso de Ingeniería del Transporte (CIT 2021), realizado en modalidad online los días 6, 7 y 8 de julio de 2021, organizado por la Universidad de Burgos, Working hours in Spain is generally last for 8 hours per day with a maximum of 40 hours per week. Working hours, therefore, can impact the traffic flow and characteristics due to the intensity of road usage by different road users. On the other side, traffic accidents can also be impacted by several temporal factors that may lead to a higher number of traffic accidents or may increase the level of injury alongside other risk factors. In this study, these timings are examined to comprehend the influence of the temporal factors represented by the working hours scheme on traffic accident injuries in Barcelona. Another temporal factor which is the season of the year is included to provide a wider and clearer image for the conducted results and the current situation. The data is collected from the open data service provided by the City Hall of Barcelona. Data preparation and segregation to include the categories of working hours that may lead to a different level of injury resulted from a traffic accident is, firstly, carried. Then, a machine learning model is applied to classify the correlations for both the temporal factors and traffic accidents. Eventually, a Tree Augmented Naïve Bayes model is applied. The results showed that both working hours timing and summer season have higher probabilities of having traffic accidents slight injuries with different medical care assistance provided compared to other timings.

Let $${\mathscr {S}}$$ be a set of n points in real four-dimensional space, no four coplanar and spanning the whole space. We prove that if the number of solids incident with exactly four points of $${\mathscr {S}}$$ is less than $$Kn^3$$ for some $$K=o(n^{{1}/{7}})$$ then, for n sufficiently large, all but at most O(K) points of $${\mathscr {S}}$$ are contained in the intersection of five linearly independent quadrics. Conversely, we prove that there are finite subgroups of size n of an elliptic curve that span less than $$n^3/6$$ solids containing exactly four points of $${\mathscr {S}}$$ .

This paper presents a framework to support the assessment of urban design projects through Urban Living Labs (ULLs). The framework is based on the Tactical Urbanism (TU) practices and involves the use of Mobile Urban Elements (MUE) in uncertain and potentially confusing conditions (e.g., the COVID-19 context). The methodology includes the application of the Four-Phase Model (problem and ideation, development, implementation, testing and assessment, final proposal) and a quantitative and qualitative assessment. The proposed assessment criteria were developed through an evaluation according to three aspects: (1) feasibility impact, (2) social impact, and (3) spatial impact. The methodology was applied to Furnish, an urban design project based on a ULL and prototyping, which was recently developed in five European cities. The empirical results, obtained using the impact analysis, indicate that the prototypes developed in the project are transferable to other cities and generate social interaction in public spaces. The applied research showed that the Four-Phase Model may be used as a new and improved iterative design process: the LOOP Scheme. The application of this assessment methodology to ULLs may provide valuable information for the future planning of urban interventions in public spaces.

In this contribution we investigate the hydrodynamic response in Alfacs Bay (Ebro Delta, NW Mediterranean Sea) to different anthropogenic modifications in freshwater flows and inner bay–open sea connections. The fresh water coming from rice field irrigation contains nutrients and pesticides and therefore affects in multiple ways the productivity and water quality of the bay. The application of a nested oceanographic circulation modelling suite within the bay provides objective information to solve water quality problems that are becoming more acute due to temperature and phytoplankton concentration peaks during the summer period when seawater may exceed 28 ∘C, leading to high rates of mussel mortality and therefore a significant impact on the local economy. The effects of different management “solutions” (like a connection channel between the inner bay and open sea) are hydrodynamically modelled in order to diminish residence times (e-flushing time) and water temperatures. The modelling system, based on the Regional Ocean Modeling System (ROMS), consists of a set of nested domains using data from CMEMS-IBI for the initial and open boundary conditions (coarser domain). One full year (2014) of simulation is used to validate the results, showing low errors with sea surface temperature (SST) and good agreement with surface currents. Finally, a set of twin numerical experiments during the summer period (when the water temperature reaches 28 ∘C) is used to analyse the effects of proposed nature-based interventions. Although these actions modify water temperature in the water column, the decrease in SST is not enough to avoid high temperatures during some days and prevent eventual mussel mortality during summer in the shallowest regions. However, the proposed management actions reveal their effectiveness in diminishing water residence times along the entire bay, thus preventing the inner areas from having poor water renewal and the corresponding ecological problems.

Wave–current interactions (WCIs) are investigated. The study area is located at the northern margin of the Ebro shelf (northwestern Mediterranean Sea), where episodes of strong cross-shelf wind (wind jets) occur. The aim of this study is to validate the implemented coupled system and investigate the impact of WCIs on the hydrodynamics of a wind-jet region. The Coupled Ocean–Atmosphere–Wave–Sediment Transport (COAWST) modeling system, which uses the Regional Ocean Model System (ROMS) and Simulating WAves Nearshore (SWAN) models, is used in a high-resolution domain (350 m). Results from uncoupled numerical models are compared with a two-way coupling simulation. The results do not show substantial differences in the water current field between the coupled and the uncoupled runs. The main effect observed when the models are coupled is in the water column stratification, due to the turbulent kinetic energy injection and the enhanced surface stress, leading to a larger mixed-layer depth. Regarding the effects on the wave fields, the comparison between the coupled and the uncoupled runs shows that, when the models are coupled, the agreement of the modeled wave period significantly improves and the wave energy (and thus the significant wave height) decreases when the current flows in the same direction as the waves propagate.

Estuaries and coastal bays are areas of large spatio-temporal variability in physical and biological variables due to environmental factors such as local wind, light availability, freshwater inputs or tides. This study focuses on the effect of strong wind events and freshwater peaks on short-term chlorophyll a (Chl a) concentration distribution in the small-scale and microtidal, Fangar Bay (Ebro Delta, northwestern Mediterranean). The hydrodynamics of this bay are primarily driven by local wind episodes modulated by stratification in the water column. Results based on field-campaign observations and Sentinel-2 images revealed that intense wind episodes from both NW (offshore) and NE-E (onshore) caused an increase in the concentration of surface Chl a. The mechanisms responsible were horizontal mixing and the bottom resuspension (also linked to the breakage of the stratification) that presumably resuspended Chl a containing biomass (i.e., micropyhtobentos) and/or incorporated nutrients into the water column. On the other hand, sea-breeze was not capable of breaking up the stratification, so the chlorophyll a concentration did not change significantly during these episodes. It was concluded that the mixing produced by the strong winds favoured an accumulation of Chl a concentration, while the stratification that causes a positive estuarine circulation reduced this accumulation. However, the spatial-temporal variability of the Chl a concentration in small-scale estuaries and coastal bays is quite complex due to the many factors involved and deserve further intensive field campaigns and additional numerical modelling efforts.

This is an Accepted Manuscript of an article published by Taylor & Francis Group in Transportation Letters on December 2020, available online at: http://www.tandfonline.com/10.1080/19427867.2020.1864134 Short-term travel time prediction on freeways is the most valuable information for drivers when selecting their routes and departure times. Furthermore, this information is also essential at traffic management centers in order to monitor the network performance and anticipate the activation of traffic management strategies. The importance of reliable short-term travel time predictions will even increase with the advent of autonomous vehicles, when vehicle routing will strongly rely on this information. In this context, it is important to develop a real-time method to accurately predict travel times. The present paper uses vehicle accumulation, obtained from input-output diagrams constructed from loop detector data, to predict travel times on freeway sections. Loop detector count drift, which typically invalidates vehicle accumulation measurements, is corrected by means of a data fusion algorithm using GPS measurements. The goodness of the methodology has been proven under different boundary conditions using simulated data. This research has been partially funded by the Spanish Ministry of Science and Innovation (Ministerio de Ciencia e Innovación, Gobierno de España), within the Program for Research Aimed at the Society’s Challenges (grant ref. PID2019-105331RB-I00). Authors especially acknowledge the work of Enrique Jiménez, who provided us with the simulation data to perform the case study.

A platoon can be defined as a group of consecutive vehicles that exchange information, so that they drive in a coordinated way, allowing very small spacings and still travelling at relatively high speeds. The concept of vehicle platooning is not new. In fact, scientific articles on platooning were published as early as the 1970s, and the first large-scale pilot test on platooning was carried out at the end of the 1990s. The main purpose of these early research works was to improve traffic efficiency and reduce consumptions, as well as to develop the existing technology. These contributions were very valuable, although somehow limited by the relevant technology still being in its infancy. Precisely, the development of technology and communications in the last years has given new ímpetus to research on vehicle platooning on freeways as one of the possible forms: of cooperation among connected automated vehicles (CAVs). The point of view of these recent studies has also been extended: in addition to traffic efficiency, the role of platooning is analyzed in terms of safety, sustainability, business productivity, etc. In this context, there are today many scientific publications on vehicle platooning with different purposes, set in distinct scenarios aud based on diverse vehicles and technologies (regular or segregated lanes, cars or trucks, vehicles with different SAE levels, etc.). In order to organize and consolidate the existing knowledge, a comprehensive and systematic review must be performed. This work represents a first approximation to this more ambitious objective. Firstly, platooning has been conceptualized in order to facilitate its analysis and comparisons among studies. Secondly, key publications on platooning have been analyzed to detennine the most significant impacts expected from its implementation. Finally, sorne important research gaps and disparate findings on the topic have been identified.

Dentro del contexto de planeación de transporte público el análisis estructural es clave para entender la eficiencia del sistema. En este trabajo se propone una metodología de análisis estructural aplicada a una red alternativa de transporte público en Guadalajara México. El análisis se deriva de teoría de redes y se enfoca en 3 propiedades: accesibilidad, resiliencia y fricción espacial. En el caso de la accesibilidad, esta se vincula con el Shimbel index que mide el promedio de tiempos de viajes de cada nodo al resto de los nodos. Por ende, el grado de accesibilidad brindará un parámetro de la efectividad en términos de tiempo de traslado que brinda cada red. Por otra parte, la resiliencia integra 3 propiedades de red los cuales son: betwenness centrality, central point dominance y average path length. El betwenness centrality mide la frecuencia en la que un aárea de la ciudad es usada como el camino más corto entre 2 destinos.Con esto se identifica las zonas con mayor polarización de uso. Mayores polarizaciones corresponderían a problemáticas de vulnerabilidades. Por otro lado, el central point dominance mide la variabilidad de la media del betwnneess centrality y el mayor betwness centrality. Una mayor variación se traduce en una mayor vulnerabilidad. Finalmente, el average path length mide el grado de conectividad de la red. Este se mide en un escenario base y se mide nuevamente cuando los principales nodos de la red fallan, esto con objeto de verificar el impacto que tiene la conectividad de la red cuando ciertos nodos fallan. Finalmente, se aborda la fricción espacial donde se toma el parámetro del índice deuter el cual compara la distancia euclidiana entre todos los posibles viajes y su distancia sobre la red de transporte. Esto otorgará un indicador de la eficiencia espacial.

[Resumen] La cantidad de preconceptos que los alumnos poseen antes de abordar el estudio de un tema influye de manera notable en la adquisición de nuevos conocimientos. Se ha diseñado una estrategia de enseñanza aprendizaje basada en el uso de cuestionarios y prácticas de ordenador realizadas con Easy Java Simulations. Las áreas trabajadas fueron mecánica, electromagnetismo y termodinámica. Se han detectado varias ideas preconcebidas y erróneas sobre todo en la parte de mecánica. Los resultados obtenidos muestran que la estrategia diseñada ha resultado útil al cometido abordado. [Abstract] The amount of preconceptions that students have before approaching the study of a topic has a significant influence on the acquisition of new knowledge. A teaching-learning strategy has been designed based on the use of questionnaires and computer practices carried out with Easy Java Simulations. The areas worked on were mechanics, electromagnetism and thermodynamics. Several preconceptions and erroneous ideas have been detected, especially in the mechanics part. The results obtained show that the designed strategy has been useful for the task undertaken. http://hdl.handle.net/2183/28796

Today, the possibility of accessing and processing large volumes of information (the binomial Big-Data ↔ Machine- Learning/IA) has motivated the review of methodologies for analysis, planning and m...

This paper analyses the spatio-temporal evolution of Ningbo-Zhoushan port growing from a feeder port to a hub port finding the historical pathways followed by its expanding in terms of container throughput capacity and total traffic. The dynamic mechanism of evolution is the results of economic globalization, containerization and its natural endowments in channel and terminal depths. Analysis of the traffic evolution and its underlying dynamics suggest 3 periods in the development processes of container transport in Ningbo-Zhoushan: (1) adoption period (1986-2000) in which the main dynamics is the impact of the Chinese ‘Open Door policy’; (2) acceleration period (2001-2008) in which the dynamics is related of the mainland China’s entry into the WTO; (3) peak growth period (2009-now) in which the dynamics is impacted by the anti-crisis strategy against the financial and economic crisis in 2008. We analyse the perspectives of Ningbo-Zhoushan port. ARIMA model is employed to forecast the container traffic in the coming future; about after 2026, the throughput in Ningbo-Zhoushan port would reach about 49 million TEU which would be approximately equal to that of Shanghai port. The resultant port development would exemplify a model of spatial distribution such as a multi-layered gateway hub. In the respect of growth potential, Ningbo-Zhoushan port possesses excellent coastline resource suitable for deep-water berthing, bonded port policy and free trade zone policy. Geographical position, service level, hinterland economic level and government will support its perspectives.

Trabajo presentado en: R-Evolucionando el transporte, XIV Congreso de Ingeniería del Transporte (CIT 2021), realizado en modalidad online los días 6, 7 y 8 de julio de 2021, organizado por la Universidad de Burgos, One of the main complaints about the performance of the bus systems is the time lost at recurrent stops along the route, that results in a low bus speed service. Among the potential measures to speed up the bus service, the introduction of the Autonomous Driving Modular Bus, able to adjust the transport unit by coupling or decoupled pods, will represent a new paradigm in the provision of service. This concept is able to maintain high stable cruising speeds to the transport unit, decoupling only one pod with passengers that may alight at the next stop. This paper analyze the potentialities of this concept in terms of user travel times and operationg cost. This work also features the formulation and analytical models to calculate the performance and oeprational variables, implementing them into two existing bus lines in Barcelona.

Trabajo presentado en: R-Evolucionando el transporte, XIV Congreso de Ingeniería del Transporte (CIT 2021), realizado en modalidad online los días 6, 7 y 8 de julio de 2021, organizado por la Universidad de Burgos, Cost-benefit analysis (CBA) is the most widely used tool for appraisal of transportation infrastructure projects, but there isn’t generalize guidelines about its implementation, there can be found different approaches that suit the perspectives of each evaluating entity. This document, it shows three different guidelines that used in practice for transportation infrastructure projects, in which there are some different costs and benefits considered informing decision makers about the project appraisal. The costs and benefits with market values have been the predominant ones in the CBA, but there is a transition to use without market values, however, there are no generalized methodologies, so more research will be needed.

This contribution examines the passenger forecasting performance of the SARIMA method applied to cruise activities in the main Spanish ports. In this port system, the cruise activity market is characterized by different seasonal patterns (i.e., once- or twice-yearly peaks, which means unimodal or bimodal behavior) due to repositioning strategy. The outcome of standard indicators for accuracy testing reveals inconsistent prediction performances among ports. These inconsistencies are analyzed using an index of bimodality and seasonal variability. The forecasted values for a high-level of bimodality and seasonal variability show worse prediction performances than unimodal patterns and low seasonal variability. Ports with less passenger activity entail larger predictions errors. Exponential and linear models were adjusted between the error metrics and the mentioned indexes.

In the near future, autonomous vehicles (AVs) will travel sharing the current freeways with human driven vehicles. The efficiency of this mixed traffic scenario will depend on the ability of AVs to behave cooperatively. Otherwise, the introduction of uncoordinated AVs might lead to capacity reductions. Connected AVs (CAVs) traveling in platoons represents a promising management strategy to get the most from the AVs’ technological revolution. Most of previous research has used traffic microsimulation tools to assess platooning and other CAVs’ cooperative driving strategies, achieving good results. However, the robust macroscopic modeling alternative, which typically yields the necessary insights and fundamental knowledge to set the foundations for the development of management and control strategies, remains almost unexplored. This paper contributes to fill this research gap by providing a generalized macroscopic model to estimate the average CAVs platoon length for a given traffic demand and penetration rate of CAVs. Two different platooning schemes are compared (i.e. cooperative and opportunistic) representing the best and worst case scenarios. The estimation of CAVs platoon length is of much importance as it is the main factor driving capacity improvements on freeways, which under the appropriate conditions could exceed 10.000 vehicles per hour and lane. Authors acknowledge Prof. Frosso Makri for her guidance in the computation of the average opportunistic platoon length. Also, the comments to preliminary versions of the paper of Mr. Marcos Medina and Mr. Enrique Jimenez are gratefully acknowledged. This research has been partially funded by the Spanish Ministry of Science and Innovation ( Ministerio de Ciencia e Innovación, Gobierno de España ), grant number PID2019-105331RB-I00.