Abstract

The just-in-time (JIT) delivery of products is a considerable challenge for many firms, because suitable planning methods have to be developed and practically installed. One main problem refers to the suppliers’ strategy, as they are no longer able to keep their optimal lot sizes and production rates due to customers’ reduced call-forward rates (cf. e.g. Fandel et al. 1988 and Fandel 1988). Thus, the suppliers have to choose different planning procedures in order to assure that there will be no avoidable in-process costs, as concerns particularly the production, inventory, and transportation of products. Obviously, there exist remarkable trade-offs between the design parameters of the whole process (cf. Reese 1991), which require a simultaneous optimization of all variables. Document type: Part of book or chapter of book

Abstract

Rail transport generally has the advantage for large-volume long-haul freight operations. The literature generally shows that shipping distance, costs, and reliability are among the most important determinants of people's modal choice among road, rail, air, and coastal shipping transport. However, there is little evidence in Africa, although the region historically possesses significant rail assets. Currently, Africa's rail transport faces intense competition against truck transportation. With firm-level data, this paper examines shippers' modal choice in Tanzania. The traditional multinomial logit and McFadden’s choice models were estimated. The paper shows that rail prices and shipping distance and volume are important determinants of firms' mode choice. The analysis also finds that the firms' modal choice depends on the type of transactions. Rail transport is more often used for international trading purposes. Exporters and importers are key customers for restoring rail freight operations. Rail operating speed does not seem to have an unambiguous effect on firms' modal selection. Document type: Book

Abstract

Railway transport generally has the advantage for large-volume, long-haul freight operations. Africa possesses significant railway assets. However, many rail lines are currently not operational because of the lack of maintenance. The paper recasts light on the impact of rail transportation on firm productivity, using micro data collected in Tanzania. To avoid the endogeneity problem, the instrumental variable technique is used to estimate the impact of rail transport. The paper shows that the overall impact of rail use on firm costs is significant despite that the rail unit rates are set lower when the shipping distance is longer. Rail transport is a cost-effective option for firms. However, the study finds that firms' inventory is costly. This is a disadvantage of using rail transport. Rail operations are unreliable, adding more inventory costs to firms. The implied elasticity of demand for transport services is estimated at -1.01 to -0.52, relatively high in absolute terms. This indicates the rail users' sensitivity to prices as well as severity of modal competition against truck transportation. The study also finds that firm location matters to the decision to use rail services. Proximity to rail infrastructure is important for firms to take advantage of rail benefits. Document type: Book

Abstract

Chapitre 19; International audience; With a surface area of 2.38 million km2 and a coastline of 1,200 km, Algeria is the vastest country of the Mediterranean even if it does not have the longest maritime border. These two parameters reveal the potentialities but also the challenges which characterize the logistics sector and the agribusiness infrastructures of this country. Its economy is essentially based on hydrocarbons representing more than 50% of the GDP and 98% of income from exports. The strategic sectors including agriculture and the agro-food industry were ignored in development policies in the past. It is only during these last ten years that the decrease in food dependence is considered as a priority of the government.

Abstract

Cities can increase economic growth and participate in global economic flows by acting as hubs or gateways to regional corridors, that are supported by three dimensions of connectivity: physical (infrastructure) connectivity, digital connectivity, and economic integration. Integrating these dimensions increases economic output and generates more high-quality jobs. Connectivity integration also helps a city accumulate knowledge and has positive spillover effects for the broader economy. Chongqing stands out for its well-developed infrastructure and digital connectivity, but it has yet to leverage these assets to promote regional economic integration. This report recommends: leverage existing transport infrastructure and supplement it with better integration between land, air, and water transport to build a major logistics hub; strengthen cooperation with Chengdu, Sichuan, and other regional partners to promote regional economic integration; and improve digital infrastructure with faster internet connection speeds and promote the wider adoption of digitization of services.

Abstract

This Railway Reform Toolkit aims to provide an easy-to-use resource on the rail industry and to provide an experience-based set of best practices to aid in the planning and execution of railway reforms. It s based on international experiences with railway reform under a range of railway organizational forms, state agencies, state-owned, or private enterprises. The toolkit should be particularly useful to those thinking about transitions from one organizational form to another and for those seeking to improve railway performance through investment, reorganization, or changes in government policy.

Abstract

The Channel tunnel and the Eurostar TGV have been a great chance for the Nord-Pas de Calais Region replacing it in a European and French geography. The accompanying 'Transmanche plan' has provided new infrastructures, regional integration and new opportunities. They permitted the openness to Europe and neighbourhood regions and replace definitely the Region in a European dynamic. Nevertheless, the present changing economic context, new political philosophy and the wear dried up the driving forces. If the development conditions are there it lacks a new vision and a new engine. The restructuration around the Channel tunnel concession, the Port of Calais and the rail market with new operators could be the challenge for a new development for the Kent - Nord-Pas-de-Calais integrated maritime region.; Le tunnel sous la Manche et le TGV Eurostar ont été une grande chance pour le Nord-Pas de Calais le replaçant dans une géographie européenne et française. Le «plan Transmanche" d'accompagnement a fourni de nouvelles infrastructures, l'intégration régionale et de nouvelles opportunités. Ils ont permis l'ouverture vers l'Europe et les régions voisines et de replacer définitivement la région dans une dynamique européenne. Néanmoins, le changement actuel de contexte économique, la nouvelle philosophie politique et l'usure ont tari ces forces motrices. Si les conditions de développement sont là, il manque une nouvelle vision et un nouveau moteur. La restructuration autour de la concession du Tunnel sous la Manche, le port de Calais et le marché ferroviaire avec de nouveaux opérateurs pourraient être le défi pour un nouveau développement pour la région maritime intégrée du Kent - Nord-Pas-de-Calais.

Abstract

This report describes the methodology used in the ARTEMIS rail emissions model. The approached used is a matrix of operating conditions, speeds and accelerations, for which basic parameters are used to calculated the resistance to motion of trains. Four types of resistance are included: rolling, aerodynamic, gravitational and acceleration. A necessary element in the calculation is the driving pattern, that is, the distribution of speeds and accelerations for typical operation.In the report, data are analyzed to provide operation condition distributions on both a spatial and temporal basis. The calculation procedure is evaluated with respect to resolution of operation conditions, and then evaluated by comparison with experimental data for a variety of passenger and goods trains. The results indicate that the energy consumption from modeling approach is valid to better that 10% for known operating characteristics. Emissions are calculated from the energy consumption using average fuel based emissions factors and electrical production emissions factors. Document type: Book

Abstract

[EN] Nowadays one of the main priorities for metro line operators is the reduction of energy consumption, due to the environmental impact and economic cost. In order to achieve this objective different strategies can be applied, normally focused into rolling stock, infrastructure and/or operation. Considering short-term measures and related to the traffic operation strategies, different approaches are being researched. One of the most effective strategy which reduce net energy consumption is the use of efficient driving techniques. These techniques produces a speed profile between two stations that requires the minimum net energy consumption, without degrading commercial running times or passenger comfort. In this paper, a computer model for calculating the metro vehicles speed profiles minimizing the energy consumption was developed. The equations considered in the model represent the behavior of a single vehicle operated under manual driving, subject to different constraints such as the headway, cycle time, distances and acceleration limits. The proposed model calculates different commands to be systematically executed by the driver. The resulting simulator has been tuned by means of on board measurements of speed, accelerations and energy consumption obtained along different lines in Metro de Valencia network. For this purpose, different scenarios are analyzed to assess the achievable energy savings. In general terms and comparing with the actual energy consumption, the solutions proposed can reduce the net energy consumption around 19% The authors wish to thank Ferrocarrils de la Generalitat Valenciana (FGV) for their kind support during the development of this study, including their assistance during the installation of the consumption devices aboard their trains and their permission to carry out measurements during the normal service. This project has by funded by the Spanish Ministry of Economy and Competitiveness (Ref. TRA2011-26602). Villalba Sanchis, I.; Salvador Zuriaga, P. (2016). An energy-efficient metro speed profiles for energy savings: application to the Valencia metro. En XII Congreso de ingeniería del transporte. 7, 8 y 9 de Junio, Valencia (España). Editorial Universitat Politècnica de València. 1820-1832. https://doi.org/10.4995/CIT2016.2016.3774 OCS 1820 1832