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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.

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.

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.

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.

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 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

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.

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.

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.

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.

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, This paper analyzes the effect of the limited range of battery electric bus on the operation of the bus services charged at the bus garage. A model has been built to calculate the performance of the routes according to the type of charging scheme. It evaluates the total cost of the bus service, considering the necessary resources due to range limitations and electric constraints. Based on the analysis of the real data of a bus line in the city of Barcelona, diesel or hybrid vehicles are still found to be more competitive than electric vehicles because of the acquisition costs of electrical technology. The study shows that the charging operation at the bus garage, without being the most profitable option a priori, is adequate when the design and operation parameters of the bus route fall below certain values.

The Yangtze River Delta (YRD) is the most developed area in China attracting global attention. Noting that the concentration ratio (CR(n)), Herfindahl-Hirschman Index (HHI) (also including Gini coefficient and Aitchison distance) and shift-share analysis (SSA) are only allowed to describe the concentration, inequality and competition of a multi-port system respectively. A novel ternary diagram method is proposed to include these five methods together and provide a comprehensive and visual tool to conveniently investigate the concentration gradient, inequality and competition of the YRD multi-port system simultaneously. The ternary diagram also permit to substitute individually for the CR(n), HHI (also including Gini coefficient and Aitchison distance) and SSA as a tool to investigate the concentration, inequality and competition of a multi-port system. This method provides a new perspective for better interpretation of the spatial and temporal evolution of shipping and multi-port systems.

Many transit network layouts require the operation of multiple routes along a common transit segment in the busiest area of the city. At some points, these routes branch out to provide spatial coverage to the city periphery. These schemes allow more efficient deployment of resources at the expense of introducing more complexity into the system operation. This study aims to determine the effect of the branched layout of a corridor, demand distribution and traffic lights on the total cost of the system as well as its service regularity. The transit corridor is operated by buses, although it can be generalized for other transit modes. An operational model to estimate the travel and waiting time of users and the performance of buses on each route segment is developed. The model considers the stochastic effect of the passenger arrivals at stops and vehicle acceleration–deceleration rates. An optimization procedure to determine the optimal headway and relative synchronization of routes, which minimizes the total cost incurred by transit agencies and users or the headway variations in the common route segment, is introduced. Furthermore, a performance evaluation of bus control strategies based on a combination of holding points and green extensions at traffic signals in the H10 cross-town corridor of Barcelona’s new bus network is presented.

Recent years have seen a renewed interest in Variable Speed Limit (VSL) strategies. New opportunities for VSL as a freeway metering mechanism or a homogenization scheme to reduce speed differences and lane changing maneuvers are being explored. This paper examines both the macroscopic and microscopic effects of different speed limits on a traffic stream, especially when adopting low speed limits. To that end, data from a VSL experiment carried out on a freeway in Spain are used. Data include vehicle counts, speeds and occupancy per lane, as well as lane changing rates for three days, each with a different fixed speed limit (80 km/h, 60 km/h, and 40 km/h). Results reveal some of the mechanisms through which VSL affects traffic performance, specifically the flow and speed distribution across lanes, as well as the ensuing lane changing maneuvers. It is confirmed that the lower the speed limit, the higher the occupancy to achieve a given flow. This result has been observed even for relatively high flows and low speed limits. For instance, a stable flow of 1942 veh/h/lane has been measured with the 40 km/h speed limit in force. The corresponding occupancy was 33%, doubling the typical occupancy for this flow in the absence of speed limits. This means that VSL strategies aiming to restrict the mainline flow on a freeway by using low speed limits will need to be applied carefully, avoiding conditions as the ones presented here, where speed limits have a reduced ability to limit flows. On the other hand, VSL strategies trying to get the most from the increased vehicle storage capacity of freeways under low speed limits might be rather promising. Additionally, results show that lower speed limits increase the speed differences across lanes for moderate demands. This, in turn, also increases the lane changing rate. This means that VSL strategies aiming to homogenize traffic and reduce lane changing activity might not be successful when adopting such low speed limits. In contrast, lower speed limits widen the range of flows under uniform lane flow distributions, so that, even for moderate to low demands, the under-utilization of any lane is avoided. These findings are useful for the development of better traffic models that are able to emulate these effects. Moreover, they are crucial for the implementation and assessment of VSL strategies and other traffic control algorithms., Transportation Research Part C: Emerging Technologies, 77, ISSN:0968-090X

This paper applies a mathematical model for supporting the decision and policy making in the city of Barcelona, presenting the key performance indicators of the Barcelona taxi market, which are waiting/access time and benefits of the drivers. The model accounts for demand elasticity, which allows for estimating the optimum fare level and estimating the related demand for taxi services, which allows the taxi decision makers to have a rough estimation of the taxi sector turn over. In addition, the model is applied to a full-day time period, allowing for useful insights on the duration and distribution of the taxi shifts that should be defined by the taxi policy makers as well as the optimal operation mode for each interval of the day. Finally, the model implementation in the city of Barcelona determines that the optimum fares for the taxi sector is 0.68 euros/kilometer and the optimum number of taxis is 19 taxis/km2. In this situation, the most effective taxi policy is to have 4 days with an 8-h shift and one day with two non-consecutive 4-h shifts every week.

The statistical techniques based on compositional data are applied to investigate the evolution of the traffic share of the container throughput in a multi-port system. Compositional vectors are those which contain relative information of parts of some whole. The application of conventional statistical techniques to compositional data may lead to erroneous conclusions and spurious correlations. Therefore, compositional data (CoDa) should be treated taking into account their own mathematical structure. The so-called log-ratio approach provides a set of transformations that allow to apply conventional statistical techniques to the transformed compositional data samples. Thus, the objective of this paper is double. As a first stage it aims to introduce the CoDa formalism and highlight its potentiality in the port container throughput analysis as example of transport system providing an applied example: the container throughput evolution in the Spanish Mediterranean Ports system during the period 1976–2015. Second, based on the previous analysis, the aim is to characterize the container throughput in SpanishMed ports and its temporal evolution. The CoDa analysis clarifies the interpretation and data association of the container traffic throughput evolution in function of some selected change points: boom of containerization in 1990s and 2008 crisis. This contribution proves that the CoDa methodology is useful to investigate the complexity of the transport disciplines in order to understand and to manage the spatial integration that results from the movement of people and freight.

The e-commerce boom has increased the complexity of last-mile logistics operations in urban environments. In this context, unmanned aerial vehicles (UAVs), also known as delivery drones, and ground autonomous delivery devices (GADDs) show great potentialities. The objective of this paper is to provide strategic insights to adequately match these autonomous technologies with some given characteristics of cities and help define relevant decision variables. Using continuous approximation equations, the operations costs as well as the externalities induced by a) GADDs in association with an urban consolidation center (UCC) and b) truck-launched UAVs are estimated. Then, the developed mathematical formulations are applied in two different use cases: a part of the Paris suburbs (France) and the historical center of Barcelona (Spain). In less dense and larger service regions such as the Paris suburbs, truck-launched delivery drones seem more suitable to reduce the carriers’ operations costs. In denser neighborhoods such as the Barcelona historical center, GADDs are expected to be more economically profitable. In both use cases, GADDs would generate less externalities. Finally, considering the high uncertainty of some input parameters, a sensitivity analysis of the models is done. 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. The authors acknowledge the comments of anonymous reviewers that greatly helped in improving and clarifying the paper.

During the last decade, public bike-sharing systems have gained momentum and popularity. Many cities worldwide have put their trust in bike-sharing to promote bicycle use and move towards more sustainable mobility. This paper presents a parsimonious model from which to derive the optimal strategical design variables for bike-sharing systems (i.e. the number of bicycles, the number of stations and the required intensity of rebalancing operations). This requires an integrated view of the system, allowing the optimization of the trade-off between the costs incurred by the operating agency and the level of service offered to users. The approach is based on the modelling technique of continuous approximations, which requires strong simplifications but allows obtaining very clear trade-offs and insights. The model has been validated using data from Bicing in Barcelona, and the results prove, for example, the existence of economies of scale in bike-sharing systems. Also, station-based and free-floating system configurations are compared, showing that free-floating systems achieve a better average level of service for the same agency costs. In spite of this, the performance of free-floating systems will tend to deteriorate in the absence of a strong regulation. Furthermore, if electrical bikes are used, results show that battery recharging will not imply an active restriction in station-based configurations. In conclusion, the proposed modeling approach represents a tool for strategic design in the planning phase and provides a better understanding of bike-sharing systems

The final publication is available at Springer via http://dx.doi.org/10.1007/s13437-018-0143-6 This contribution investigates the economic benefits of using weather ship routing on Short Sea Shipping (SSS) activities. The investigation is supported with the development of a ship routing system based on pathfinding algorithm, the parametrization of the wave effect on navigation, and the use of high-resolution meteo-oceanographic predictions. The optimal ship routing analysis is investigated in a European SSS system: the link between Spanish and Italian ports. The results show the economic benefits using ship routing in SSS during energetic wave episodes. The rate of cost savings may reach 18% of the total costs under particular bad weather conditions in the navigation area. The work establishes the basis of further developments in optimal route applied in relatively short distances and its systematic use in the SSS maritime industry.

This is the peer reviewed version of the following article: [Ros Chaos S, Pino Roca D, Saurí Marchán S, Sánchez‐Arcilla Conejo A. Cruise passenger impacts on mobility within a port area: Case of the Port of Barcelona. Int J Tourism Res. 2018;20:147–157. https://doi.org/10.1002/jtr.2165], which has been published in final f orm at https://doi.org/10.1002/jtr.2165.This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving. Cruise tourism has grown rapidly worldwide over the past 30 years. This increase in cruise passengers has brought a set of economic, socio-cultural, and environmental impacts. In a port context, it is reflected in mobility problems with long waiting times and queues. To assess cruise passenger impacts, a mobility analysis was performed. The results of this analysis demonstrate the importance of the disembarkation operation. Passengers have to be moved in short periods of time. It is vital to organize mobility and to have sufficient transport modes to move passengers to their inland destinations quickly, safely, and efficiently.

A basic question for the assessment of the fairness of a project financing formula on successive generations is to determine what is the most appropriate method to group the affected individuals over the years. The generational approach in the “Intergenerational Redistributive Effects Model” (IREM) deals with it through the ad-hoc concept of overlapping annual generations. This concept requires establishing the number of years (or timespan) included in the generation and how to incorporate in it those individuals living in years that are not the central one. To do so in a way that reflects the sensitivity of society to the effects of a major transport infrastructure project, specific surveys with a novel approach were designed. The outputs from the survey carried out in Catalonia show evidence suggesting that discount functions should tend to decline at a higher rate in the short term than in the long term. Thus, future impacts of transport investments, both future socio-economic net benefits and financial burdens, should be considered less important than immediate (present) outcomes in the decision-making process. Further, there are reasons to consider that discounting is not neutral to reflect the social interest of large-scale transport projects for the successive generations involved.

Conventional wisdom states that transit riders are averse to transfers and that consequently bus networks should be designed to limit their number. Probably as a result of this belief, many real bus systems try to connect as many origins and destinations as possible without transfers, so they are usually composed of long, circuitous routes with redundant overlapping sections – and the resulting bus map is hard to understand. If coverage is extensive, many routes are needed. Economics then prevents an agency from populating all routes with sufficient buses to provide attractively frequent service. This low frequency and the complicated circuitous map discourage transfers, perpetuating the belief that people are averse to transferring. Not surprisingly, the percentage of bus trips that includes a transfer has been reported to be: 1.5% for Boston, 3% for New York, 13% for London, and 16% for Melbourne. The Nova Xarxa in Barcelona was designed with a different paradigm. It was designed and deployed to cover the whole city on the belief that if a bus map is easy to understand, and has direct lines with frequent service and ubiquitous transfer points then the bus system would become more appealing, people would transfer more freely and become users of the network rather than its single lines. With this design paradigm, a city can be covered with fewer lines, which can be depicted on a simple map. The lines can in turn be economically populated with sufficient buses to deliver the high frequency required to encourage transfers. Could this work? To answer this question and see whether there is truth in the beliefs underlying the new paradigm, this paper examines data from the first three deployment phases of the Nova Xarxa (from 2012 to 2015). It is found that the Nova Xarxa is already attracting more demand than the network it replaced. This attests to its appeal. Furthermore, this demand has increased disproportionately with the number of lines opened for service in each phase, revealing that some people are using the Nova Xarxa as a network. The paper further shows that this growth is underpinned by transfers -- at the end of 2015, the percentage of trips that involved a transfer was approximately 26%, and it reached a maximum of 57% for line V7. These numbers should increase considerably (to 44% and 66%, respectively) once the Nova Xarxa is completed in 2018 and passengers have even more opportunities for transferring. The numbers disprove the conventional wisdom. They strongly suggest that transit providers can attract more demand by providing transfer-friendly networks that can be used as such and not as an inefficient aggregation of individual lines.

This paper provides an estimation of air emissions (CO2, NOX, SOX and PM) released by cruise vessels at the port level. The methodology is based on the Bfull bottom-up^ approach and starts by evaluating the fuel consumed by each vessel on the basis of its individual port activities (manoeuvring, berthing and hoteling). The Port of Barcelona was selected as the site at which to perform the analysis, in which 125 calls of 30 cruise vessels were monitored. Real-time data from the automatic identification system (AIS), factor emissions from engine certificates and vessel characteristics from IHS Sea-web database were also collected for the analysis. The research findings show that the most appropriate indicators are inventory emissions per Bport-time gross tonnage^, Bport-time passenger^ and Bport time^. These emission indicators improve our understanding of cruise emissions and will facilitate the work that aims to estimate reliably and quickly the in-port ship emission inventories of cruise ports.

This contribution investigates the container throughput flow in a multi-port gateway system: Barcelona-Tarragona-Valencia (BTV). First, the paper examine the recent dynamics of the total and transshipment flow showing a relevant shifting of traffic share from Barcelona to Valencia. A statistical model based on a two-state Markov model in conjunction with a Monte Carlo experiments is implemented to estimate the predictions of container throughput in BTV system. Verification tests shows how the predictions are reasonable good with an error metrics similar to other methods based on time series analysis. The method is considered suitable for short-term forecasting with a strong potential to be used as a complement of qualitative methods due to the statistical nature of the results. The implementation of the method considers separately the import/export and transhipment container throughput revealing a differentiate dynamics in both container flows. The transhipment flow is more volatile and induce more data dispersion in the container throughput predictions.

This paper proposes a bilevel formulation for solving the Bus Network Design Problem (BNDP) of interurban services entering a major city. It is focused in interurban services because it is a growing problem in most of major cities, yet new in the literature. The layout of interurban bus routes and the locations of transfer stations in the main city are the key factors to provide a competitive public transportation service to commuters in a metropolitan area. The number of commuters in huge urban concentrations is growing due to the difficulties of living near the city center. The objective function of the first level is defined with the aim of reducing user and agency costs. In the second level the performance of users is addressed. Furthermore, a local search method based on the Tabu Search algorithm was carried out to guide the exploration in the solution domain. The results obtained in a set of test problems have demonstrated that the restart parameters of the algorithm play a significant role in the efficiency of the algorithm. Finally, implementation in the large network of Barcelona (Spain) reduces the total cost by 5% with regard to the present situation.

[Abstract:] The introduction of autonomous vehicles (AV) will represent a milestone in the evolution of transportation and personal mobility. AVs are expected to significantly reduce accidents and congestion, while being economically and environmentally beneficial. However, many challenges must be overcome before reaching this ideal scenario. This study, which results from on-site visits to top research centres and a comprehensive literature review, provides an overall state-of-the-practice on the subject and identifies critical issues to succeed. For example, although most of the required technology is already available, ensuring the robustness of AVs under all boundary conditions is still a challenge. Additionally, the implementation of AVs must contribute to the environmental sustainability by promoting the usage of alternative energies and sustainable mobility patterns. Electric vehicles and sharing systems are suitable options, although both require some refinement to incentivise a broader range of customers. Other aspects could be more difficult to resolve and might even postpone the generalisation of automated driving. For instance, there is a need for cooperation and management strategies geared towards traffic efficiency. Also, for transportation and land-use planning to avoid negative territorial and economic impacts. Above all, safe and ethical behaviour rules must be agreed upon before AVs hit the road. Ministerio de Economía y Competitividad; TRA2016-79019-R/COOP

This paper presents the necessary conditions to ensure a minimal profitability of carrier-led consolidation strategies in urban distribution. These conditions are shown by compact formulas obtained by continuous approximations representing the cost of the stakeholders involved: society, regular carriers, consolidation facility operator and environment. The domain of the retailer density variable that always produces negative effects on each stakeholder has been identified. The envelope of this domain does not depend on vehicle costs and other site-related parameters. On the other hand, there is a critical density of receivers that makes the carrier cost savings higher than the CF operator costs.

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 World Trade Organization; (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.