Calibration and Validation of Strategic Freight Transportation Planning Models with Limited Information

Strategic transportation network models are often used as support tools in the framework of decisions to be taken at the policy level, such as the Trans-European Network projects. These models are mostly setup using aggregated or limited data. If their calibration is regularly mentioned in the literature, their validation is barely discussed. In this paper, several modal choice model specifications that make only use of explanatory variables available at the network level are described and applied to a large scale case. A validation exercise is performed at three levels of aggregation. The paper is designed from a strategic transport planning perspective, and does not present new modal choice formulations or assignment procedures. Its main added value is the focus on calibration and validation considerations. Despite the limited explanatory information used, the global performance of the best models can be considered as satisfactory. However, the quality of the models varies from mode to mode, the use of railway transport being the most difficult to predict without more specific input.

Empirical Analysis of Multiple-Criteria Decision-Making (Mcdm) Process for Freight Transportation Mode Selection

In Ghana, freight transport is growing continuously every year due to its location and business processes. However, road transport carries 86% of freight despite its numerous negative impacts. Hence, the government has invested in rail transport, with 70% of its capacity is for freight transport in her busy freight transport corridor (eastern transport regions of Ghana). Thus, awareness of criteria considered when deciding on freight transport becomes vital. Hence, this study aims to improve the understanding of the factors of freight transport mode selection in Ghana from the decision-making process by identifying criteria that affect their decisions on mode transportation. The combination of Fuzzy AHP and Topsis is used to find the weights and suggest suitable alternatives for the decision-makers in the Eastern transport regions of Ghana. The result of this study shows that the criteria to consider when selecting freight transport mode in the regions are prioritized in other of Transport cost (0.6544), transport Time factors (0.2562), reliability, and flexibility (0.0605), and security, Risk of damage and lose factors (0.0287). Additionally, the suitable mode(s) of transportation in the stated corridor is owned truck carrier transport compared to the railroad, road-barge, and Contracted Carrier, thus, in descending order. The results provide organizations to prioritize these factors when deciding to select freight transport mode. At the same time, the government must remove some inputs that result in high transport costs, enforce policies, and invest in the appropriate mode.

Accessibility Measures in Modal Choice Models: A Proof of Concept Applied to Freight Transport

Modal choice models applied to interregional or international freight transportation network models are often based on rather coarse origin-destination matrices, containing annual transported tonnages between (sub)regions, for instance. Generally, only basic (sometimes constructed) independent variables (transportation costs or transit times) are used because other variables such as shipment sizes, service frequencies, etc. are not available. Using origin-destination matrices and an assignment model, it is also possible to compute spatial accessibility measures that can further be used as additional explanatory variables. Indeed, several published studies have identified network accessibility as an important element in the mode-choice decision. This paper also shows that the inclusion of an accessibility measure in the utility functions of a logit model substantially improves the performance of a transportation network model, both in the modal choice and the assignment levels of the classical four-step model. Consequently, the assignment of the estimated modal demands results in more accurate estimated traffic on the networks. The model presented in this paper is to be considered as a proof of concept because its workflow should further be streamlined to make it easily useable by modelers.

Intermodal Freight Network Design for Transport of Perishable Products

The amount of perishable products transported via the existing intermodal freight networks has significantly increased over the last years. Perishable products tend to decay due to a wide range of external factors. Supply chain operations mismanagement causes waste of substantial volumes of perishable products every year. The heretofore proposed mathematical models optimize certain supply chain processes and reduce decay of perishable products, but primarily deal with local production, inventory, distribution, and retailing of perishable products. However, significant quantities of perishable products are delivered from different continents, which shall increase the total transportation time and decay potential of perishable products as compared to local deliveries. This paper proposes a novel optimization model to design the intermodal freight network for both local and long-haul deliveries of perishable products. The objective of the model aims to minimize the total cost associated with transportation and decay of perishable products. A set of piecewise approximations are applied to linearize the non-linear decay function for each perishable product type. CPLEX is used to solve the problem. Comprehensive numerical experiments are conducted using the intermodal freight network for import of the seafood perishable products to the United States to draw important managerial insights. Results demonstrate that increasing product decay cost may significantly change the design of intermodal freight network for transport of perishable products, cause modal shifts and affect the total transportation time and associated costs.

ComplexTrans-Global Rail-Road Transportation System Economical and Clustered Individual and Individualised Public Transport also Prevents the Spread of Covid 19

Land transport can no longer meet the requirements.European transport can be described by these words−crowded motorways and cities,dangerous emissions,ubiquitous traffic accidents,delays,expensive railways.Solutions are being sought to transfer a large part of passengers and especially freight transport to(high-speed)rail,and efforts are moving towards electromobility,car-sharing,5G-connectivity,autonomous driving,MaaS(Mobility as a Service)-coordinated transport or hyperloop-type solutions.However,all these solutions have additional challenges and limitations.Solutions are not being searched where they really exist-in the mutual adaptation of road and rail vehicles and their deep cooperation.The ComplexTrans project shows that simply adapting the dimensions and functions of road and rail vehicles can eliminate(or at least significantly reduce)all the problems of existing land transport.The main features of the ComplexTrans system are sufficient parking spaces,reduction of urban and non-urban congestion,electric vehicles with unlimited range and cheaper than standard cars,cheaper and more accessible battery charging,“autonomous ride”,solving the overlap between passenger and freight rail transport and making it self-financing,transferring intercity freight transport to rail,replacing part of continental air transport and many others.The cost-effective and clustered individual transport and individualised public transport of the ComplexTrans system also bring very significant reductions in the risk of transmission of covid-19 and other contagious diseases during transport.

Factors Analysis of Affecting Loading and Reinforcing Scheme of Large Goods in Railway

Large goods transported in railway are kinds of special goods and they are very important in national construction. In order to transport safely, loading and reinforcing schemes must be made first. How to design a reasonable scheme will be affected by many factors. This paper presents the characteristic of the large goods, summarizes the process of designing a loading and reinforcing scheme of large good, then probes the factors of affecting the loading and reinforcing scheme and gives a detail analysis. It’s considered that those out-of-gauge and overweight degree of goods, center-of- gravity height of a loaded wagon, position of center-of-gravity of goods, type of wagon for using, reinforcement material and reinforcement method, transport expense and transport organization could affect a scheme in the aspects of safety, economy, rapidity and convenience. This conclusion will instruct and help to make a good scheme.

货车“司机荒”现象的成因及对策

当前,货车司机已经成为稀缺的人力资源,即使企业承诺高薪,应聘者还是寥寥无几。快递业的高速发展产生了大量的货车司机的需求,但受限驾考制度,驾培资源以及年轻人的职业观等因素,每年获得货车驾驶执照的人数不多,远不能满足市场需求。通过优化管理制度,投入更多驾培资源,创新物流业务模式,鼓励年轻人获取资质,能够有效地缓解这一困局。

城市交通与居民健康研究进展

Urban transportation is a major element of sustainable urban development and a key factor affecting the health of urban residents.It influences public health through noise,air pollution,social isolation,inactive modes of transportation,and sedentary behaviors.This paper reviews literature related to urban transportation and health from two perspectives:travel behavior and environmental impact.It focuses on passenger transportation and freight transportation to analyze their respective negative environmental externalities,such as noise,environmental pollution,and accidents.After the literature review,the paper identifies the main deficiencies in urban transportation research aiming to build healthy cities,and proposes measures and suggestions for future research.

A methodology for assessing the urban supply of on-street delivery bays

The loading and unloading operations carried out by transport and logistics operators have a strong impact on city mobility if they are not performed correctly.If loading/unloading bays,i.e.,delivery bays(DB),are not available for freight vehicle operations,operators may opt to double park or park on the sidewalk where there is no strong enforcement of these laws,with significant impact on congestion.This paper proposes a methodology for verifying and designing the number of delivery bays needed for freight vehicles for not interfere with cars or pedestrians.The methodology consists of two stages:in the first stage,an initial estimation is made using queueing theory.Subsequently,in the second stage,using such tentative scenario,in order to take into account the system stochasticity involving different entities,a discrete event simulation is performed to more realistically verify and upgrade(if necessary)the number of delivery bays to obtain the expected outcomes.The methodology was applied in the inner area of Santander(Spain).The study area was subdivided into 29 zones where the methodology was applied individually.The results indicated that none of these zones currently have an optimal number of delivery bays to satisfy demand.In some zones,there is an excess of delivery bays,although in most of them,there is a deficit which can cause significant impacts on traffic.The method proposed can be an effective tool to be used by city planners for improving freight operations in urban areas limiting the negative impacts produced in terms of internal and external costs.