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The reduction of urban congestion represents one of the main challenges for increasing sustainability. This implies the necessity to increase our knowledge of urban mobility and traffic. The fundamental diagram (FD) is a possible tool for analyzing the traffic conditions on an urban road link. FD is commonly associated with the links of a transport network, but it has recently been extended to the whole transport network and named the network macroscopic fundamental diagram (NMFD). When used at the link or network level, the FD is important for supporting the simulation, design, planning, and control of the transport system. Recently, floating car data (FCD), which are based on vehicles' trajectories using GPS, are able to provide the trajectories of a number of vehicles circulating on the network. The objective of this paper is to integrate FCD with traffic data obtained from traditional loop-detector technology for building FDs. Its research contribution concerns the proposal of a methodology for the extraction of speed data from taxi FCD, corresponding to a specific link section, and the calibration of FDs from FCD and loop detector data. The methodology has been applied to a real case in the city of Santander. The first results presented are encouraging, supporting the paper's thesis that FCD can be integrated with data obtained from loop detectors to build FD. [ABSTRACT FROM AUTHOR]

Urban mobility is evolving today towards the concept of Mobility as a Service (MaaS). MaaS allows passengers to use different transport services as a single option, by using a digital platform. Therefore, according to the MaaS concept, the mobility needs of passengers are the central element of the transport service. The objective of this paper is to build an updated state-of-the-art of the main disaggregated and aggregated variables connected to travel demand in presence of MaaS. According to the above objective, this paper deals with methods and case studies to analyze passengers' behaviour in the presence of MaaS. The methods described rely on the Transportation System Models (TSMs), in particular with the travel demand modelling component. The travel demand may be estimated by means of disaggregated, or sample, surveys (e.g., individual choices) and of aggregate surveys (e.g., characteristics of the area, traffic flows). The surveys are generally supported by Information Communication System (ICT) tools, such as: smartphones; smartcards; Global Position Systems (GPS); points of interest. The analysis of case studies allows to aggregate the existing scientific literature according to some criteria: the choice dimension of users (e.g., mode, bundle and path, or a combination of them); the characteristics of the survey (e.g., revealed preferences or stated preferences); the presence of behavioural theoretical background and of calibrated choice model(s). [ABSTRACT FROM AUTHOR]

The paper deals with the interaction between freight flows, land use, and economy of a suburban area. In urban freight distribution, the process of freight acquisition of commercial establishments represents a crucial element. Therefore, it is necessary to plan city logistics in order to reduce the negative externalities generated by freight transport without depressing the economic and social vitality. In order to estimate and evaluate the performance and impacts generated by urban freight distribution, Transport System Models (TSMs) play an important role in reproducing and forecasting the process of distribution of final products to retailers and consumers. In recent years, Information and Communication Technologies (ICTs) have made new sources of data in great amounts available at lower costs than data provided from traditional surveys. Among the different data sources, Floating Car Data (FCD), obtained through GPS trackers installed on board the vehicles, offer partial insights into the examined process with lower cost and provide continuous information in space and time. In order to obtain reliable results, it is necessary to combine TSMs and ICTs as observed data could feed Transport System Models and could allow their calibration and therefore their application in real cases. In the above context, the paper deals with TSMs related to estimating urban freight demand flows. The work carried out concerns the specification-calibration-validation of a freight zonal acquisition model by means of FCD related to interzonal trips of commercial vehicles inside the Locride area (Reggio Calabria, Italy). The obtained models, estimated from FCD, could support the a priori evaluation of city logistics measures. The results are more important considering that they are obtained in an area with a lack of transport monitoring technologies. They could be adopted in other similar areas and confirm that adequate planning of city logistics determines advantages for environmental, social, and economic sustainability. [ABSTRACT FROM AUTHOR]

This research concerns the topic of Land Use and Transport Interaction (LUTI) models. In particular, the patterns between residential households' location and mobility choices are analyzed and simulated. The attributes that influence household residential location choices belong to four categories: socioeconomic and mobility attributes of households and/or of their components; land use; real-estate market; transport system. The paper presents the results of a pilot study on households' location and mobility patterns in the metropolitan area of Reggio Calabria (Southern Italy). The pilot study is divided into two stages. In the first stage, a survey allowed to collect information and identify existing patterns about residential and mobility choices of a sample of households. In the second stage, a residential location model is proposed and some preliminary calibrations are presented in a prototypal way. The pilot study could be extended and improved in terms of spatial extension and sample dimension in order to allow a complete specification-calibration-validation process of the model. The model development can support the land use-transport planning process in the Metropolitan City of Reggio Calabria. [ABSTRACT FROM AUTHOR]

The paper proposes a methodology for the evaluation of an Urban Distribution Center (UDC) location in order to pursue sustainability goals. The methodology integrates indications deriving from public policies (objectives and constraints) and efficiency needs of carriers and retailers. For this reason, two planning levels are integrated into the methodology: an outer level in which a set of feasible UDC locations is defined; an inner level in which, for each location, the carrier behaviour in delivering freight to a set of retailers, characterized by variable restocking demand, is simulated (by means of a vehicle routing problem). The aim of the paper is to support the planning of city logistics measures by means of quantitative evaluations; that could be carried out by public authority to verify sustainability of logistic operations. A laboratory test is implemented in the town of Reggio Calabria (Southern Italy) to assess the effects of a combination of two city logistics measures: a nodal physical measure, such as an UDC, and an equipment measure, specifically Fully Electric Vehicles (FEVs). • Ex-ante evaluations supporting UDC location planning. • Integrated planning levels: sustainability at outer level; efficiency at inner level. • Methodology that considers at the same time public and private objectives. • Vehicle routing model with variable restocking demand scenarios. [ABSTRACT FROM AUTHOR]

This paper presents a procedure for the solution of the Vehicle Routing Problem (VRP) based on reliable link travel times. They are obtained as a combination of spatially disaggregated and aggregated data about simulated traffic conditions on an urban road network. The disaggregated data concern the congested link travel times, which are traditionally used as variable to be minimized in VRP. The novelty of this research article consists in the introduction of spatially aggregated data, which are estimated by means of the Network Fundamental Diagram (NFD). In a within-day dynamic context, they are a measure of reliability of travel times because they could anticipate the latter ones' variation in the short term. The equation of reliable link travel times is composed of a congestion term, expressing the traditional congested link travel times (or generalized costs), and a reliability term, which depends on the fundamental diagram of the link and the NFD of the homogeneous cluster of adjacent links. The proposed procedure has been validated and applied for two real test cases. NFDs data are used in the proposed link travel time function to calculate reliable travel times. The reliable link travel times are used for the solution of VRP to obtain optimal routes of freight vehicles. [ABSTRACT FROM AUTHOR]

Traffic signal setting is an important element in traffic planning of urban road networks in ordinary conditions and/or in emergency conditions. As traffic signal setting affects user behaviour mainly at the path choice dimension, this dependence has to be studied by means of assignment models. We thus present a system of models and procedures for signal setting optimization with assignment of travel demand to a congested road transport network. Two interacting procedures are developed to solve the system of models: (i) an optimization procedure to obtain an optimal configuration of signal setting parameters and (ii) an assignment procedure, incorporating a path choice model with explicit path enumeration and a flow propagation model, to capture the effects of signal setting configuration on user path choice behaviour. The system of models and procedures is applied and validated on a real test site, where the transport system is in dynamic conditions due to the time-varying road network and travel demand. The test site is a portion of a small-size town where the population needs to be evacuated due to an imminent calamitous event. The results show considerable reductions in total delays on the network and evacuation times in the case of optimized signal setting parameters. [ABSTRACT FROM AUTHOR]

The presence of transhipment services in a region has previously been analyzed relative to ports and shippers with no consideration to the geographical factors of the sea basin serving the region. We hypothesize that attributes related to basin morphology also should be considered, as the processes involved in the maritime container freight market are comparable to processes in other transport markets. We show that transhipment services are relevant in those regions with closed sea basins. This article addresses the following issues: the traditional analytic methods used to determine, directly or indirectly, the presence of transhipment services; the role of transhipment in some geographic regions by estimating the rate of transhipment relative to throughput for each region; and the estimation of a statistical model that can determine the presence of transhipment by means of aggregate variables related to the morphology of a sea basin serving each region and to the socioeconomic characteristics of the region served. La presencia de servicios de transbordo en una región ha sido analizada en relación a los puertos y cargadores, sin considerar los factores geográficos de las cuencas marítimas al servicio de una región. Nuestra hipótesis es que los atributos relacionados a la morfología de las cuencas también deberían tomarse en cuenta, ya que los procesos involucrados en el mercado de contenedores de carga marítima son comparables a los procesos de otros mercados de transporte. Mostramos que los servicios de transbordo son relevantes en aquellas regiones con cuencas marítimas cerradas. El presente artículo aborda los siguientes temas: los métodos analíticos tradicionales generalmente usados para determinar, directa o indirectamente, la presencia de servicios de transbordo; el rol del transbordo en algunas regiones geográficas, a partir de la estimación de las tasas de transbordo relativas a su rendimiento ( throughput) en cada región; y la estimación de un modelo estadístico que pueda determinar la presencia de transbordo a partir de variables agregadas relacionadas a la morfología de la cuenca marítima al servicio de cada región, y a las características socioeconómicas de cada región. 区域海运转运服务的分析已经将港口和航运商纳入研究范畴，但忽视了区域海洋盆地地理因素的影响。由于参与海运集装箱货运市场的过程与其他运输市场的过程具有可比性，因而本文认为和海盆形态有关的属性也应考虑在内。研究结果显示，转运服务与那些靠近海盆的区域具有相关性。本文将重点对以下问题进行阐述：过去经常用来直接或间接判断转运服务的传统分析方法；通过估计一个地区相对于自身吞吐量的转运率来判断部分地理区域在转运服务中的角色；通过区域海盆形态和社会经济属性相关的综合变量，构建能够判别转运服务的统计模型. [ABSTRACT FROM AUTHOR]

Abstract: Much effort has been expended in the last decades in developing modelling frameworks to simulate the so-called Spatial Economic Transport Interaction (SETI) process. Models have been originated according to autonomous bodies of knowledge connected to the analysis and interpretation of each reference spatial scale: urban and national. However, there have been few exchanges of knowledge flowing from one scale to another. This paper proposes a unifying modelling framework able to capture the two-way relationship between spatial economic and transport systems at both the national and urban scales. Four main elements are presented: (i) a literature review of Spatial Economic (SE) models at national and urban scales; (ii) a description of the theoretical evolution involving a class of SE models from the theoretical backgrounds to the current formulations; (iii) the proposition of a SETI model which has two modelling components: a transport macro-model and a spatial economic macro-model; (iv) a model specification for national and urban scales. [Copyright &y& Elsevier]

This paper focuses on the estimation of energy consumption of Electric Vehicles (EVs) by means of models derived from traffic flow theory and vehicle locomotion laws. In particular, it proposes a bi-level procedure with the aim to calibrate (or update) the whole parameters of traffic flow models and energy consumption laws by means of Floating Car Data (FCD) and probe vehicle data. The reported models may be part of a procedure for designing and planning transport and energy systems. This aim is to verify if, and in what amount, the existing parameters of the resistances/energy consumptions model calibrated in the literature for Internal Combustion Engines Vehicles (ICEVs) change for EVs, considering the above circular dependency between supply, demand, and supply–demand interaction. The final results concern updated parameters to be used for eco-driving and eco-routing applications for design and a planning transport system adopting a multidisciplinary approach. The focus of this manuscript is on the transport area. Experimental data concern vehicular data extracted from traffic (floating car data and probe vehicle data) and energy consumption data measured for equipped EVs performing trips inside a sub-regional area, located in the Città Metropolitana of Reggio Calabria (Italy). The results of the calibration process are encouraging, as they allow for updating parameters related to energy consumption and energy recovered in terms of EVs obtained from data observed in real conditions. The latter term is relevant in EVs, particularly on urban routes where drivers experience unstable traffic conditions. [ABSTRACT FROM AUTHOR]

The mobility of people and goods represents an essential activity that influences sustainability owing to energy consumption. Generally, electrical mobility problems concern the selection of technology (e.g. electrical vehicles (EVs)), monitoring the ex-post effects of their implementation. However, an ex-ante quantitative assessment of transport services in relation to travel demand is necessary in decision-making processes. The objective of this study is to propose a framework that supports decision-making regarding the optimisation of transport services for people in an effort to minimise renewable energy resources. Transport system models (TSMs) are the core of the framework, adopted to design transport services operated with EVs. TSMs are examined in a practical scenario, represented by the touristic port "Porto delle Grazie", located in the Città Metropolitana of Reggio Calabria, south of Italy. Clean energy is produced from maritime waves. Transport services are designed considering travel demand by means of TSMs. The novelties of this study are a framework to support decision-making processes aimed at optimising renewable energy consumption, while ensuring the satisfaction of mobility requirements, and an application in a practical scenario where energy is produced by the sea waves to facilitate green transport services for people mobility. The application represents a prototypical experiment aimed at validating the proposed framework. A discussion section presents the main potentialities and limitations of this work, which can be extended to wider geographical scales and over different time periods. • Framework to support a decision making process concerning sustainable mobility with elecrical vehicles. • Energy resources management and transport services optimisation. • Ex-ante quantitative assessment with Transport System Models (TSMs). • Experimentation in a port area with renewable energy produced by sea waves. • Framework to be extended at wider geographical scales and over different time periods. [ABSTRACT FROM AUTHOR]

The paper deals with the integration of data provided from traditional transport surveys (small data) with big data, provided from Information and Communication Technology (ICT), in building Transport System Models (TSMs). Big data are used to observe historical mobility patterns and transport facilities and services, but they are not able to assess ex-ante effects of planned interventions and policies. To overcome these limitations, TSMs can be specified, calibrated and validated with small data, but they are expensive to obtain. The paper proposes a procedure to increase the benefits of TSMs' building in forecasting capabilities, on one side; and limiting the costs connected to traditional surveys thanks to the availability of big data, on the other side. Small data (e.g., census data) are enriched with Floating Car Data (FCD). At the current stage, the procedure focuses on two specific elements of TSMs: zoning and graph building. These processes are both executed considering the estimated values of an intensity function of FCDs, consistently with traditional methods based on small data. The data-fusion of small and big data, operated with a Geographic Information System (GIS) tool, in a real extra-urban context is presented in order to validate the proposed procedure. [ABSTRACT FROM AUTHOR]

This research aims to verify the influence of traffic control strategies using signal plans at junctions on observed Network Macroscopic Fundamental Diagram (NMFD), as a variable to describe the aggregate traffic conditions of an urban road network. After establishing the theoretical basis of its existence, the research on NMFDs has been finalized for applications connected to traffic congestion control and management. The degree NMFD depends on traffic control strategies has not been fully demonstrated, nor has its relationship with different congestion levels. In the opinion of the authors, experimental NMFDs based on observed traffic data in the presence of different control strategies are key elements in supporting the understanding of this relationship. The paper has been structured into two parts. The first part presents the formulation of an optimization model for the design of signal plans at junctions which incorporates NMFD variables. The more extensive second part examines the effects of traffic control strategies on observed NMFDs, built with real traffic data. The investigation follows a procedure where observed traffic data are analysed to find variables, functions and diagrams at link and network levels (NMFD). The procedure is applied in two adjacent urban zones located in the central area of Santander (Spain). These zones were identified according to traffic characteristics and land uses. The junctions on the road sub-networks in the two zones have different control regulations, but they are used by the same road users (with the same behavioural strategy). Observed traffic data (flows, densities) from loop sensors have been collected and correlated with the signal control plans at different periods of a working day. What emerges from the analysis is that junction regulation affects traffic flow variables at a link and network level. The NMFDs are statistically different when comparing junction regulations at two homogenous adjacent zones. The results apply only to the studied area and should be confirmed in other real transport systems. [ABSTRACT FROM AUTHOR]