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Environmental sustainability of the transport sector is a highly important issue today. The European Commission has made a goal of delivering a minimum 60% reduction in greenhouse gas emissions from transport by 2050. Part of this reduction will come from the railway sector by making the maintenance processes more environmentally friendly. This paper presents the results of the environmental assessment of the self-propelled bulk carriage (SPBC), an innovative new product aiming to decrease the environmental impact of the railway maintenance processes. The life cycle assessment (LCA) methodology was used in the study, and environmental impact is given in five impact categories based on the CML 2001 method through three main modules of the self-propelled bulk carriage life cycle: upstream, core, and downstream. The novelty of the research includes the fact that this is the first life cycle assessment study done for the bulk carriage, as well in that the authors have proposed the use of a new functional unit in the category of freight railway vehicles. The biggest environmental impact of the self-propelled bulk carriage across all five categories is in the use and maintenance phase of its life cycle and mainly due to diesel fuel use. The SPBC uses significantly less fuel than a conventional diesel locomotive.

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In this research, field and laboratory testing of three commercially available brake pads with the lowest, mid-dle, and highest price were performed. Complex field testing, where brake pads were tested in real extreme conditions on a loaded van vehicle and laboratory tests were performed. The field testing intended to investigate the temperatures that occur during the braking process and to determine the stopping distance, deceleration, and stopping time separately on the type of brake pads. Labo-ratory tests included the determination of the friction co-efficient according to ASTM G77, the structure of brake pad surfaces before and after the testing, and quantitative chemical analysis of brake pads. The aim of this study was to determine the influence of brake pad temperature on braking time depending on their purchase prices. The obtained results show a significant difference between the temperature, friction coefficient, chemical composi-tion, and braking time of the brake pads and their price.

This paper presents the design of a fuzzy logic-based traffic scheduling algorithm aimed at reducing traffic congestion for the case of partial obstruction of a bidirectional traffic lane. Such a problem is typically encountered in rail traffic and personal rapid transportation systems with predefined and fixed traffic corridors. The proposed proportional-derivative (PD) fuzzy control algorithm, serving as a traffic control automaton, alternately assigns adaptive green light periods to traffic coming from each direction. The proposed fuzzy logic-based traffic controller has been compared with the conventional traffic control automaton featuring fixed-durations of green light intervals. The comparison has been carried out within a simulation environment for four different probability distributions of stochastic traffic flows at each end of the considered traffic corridor. Results have shown that the proposed fuzzy logic-based traffic controller performance is far superior to that of the conventional traffic control law in terms of achieving shorter vehicle queue lengths and less disparity in queue lengths for all considered simulation scenarios.

The railway sector plays an important role in the European transport sector and its environmental sustainability is a highly important issue today recognized by all the main stakeholders, including the European Commission. EU-28 railway transport network consisted of 220,000 km of railway lines in 2013. Such a big railway transport network requires maintenance. Maintenance of a railway infrastructure is a resource-and cost-demanding activity that has as well a considerable impact on the environment. This paper presents the results of the environmental assessment of an innovative new product which aims to decrease the environmental impact of the railway maintenance processes. Life cycle assessment methodology was used and results show that the biggest environmental impact, in all impact categories, is achieved in the use and maintenance phase. In the end, the normalized data of the environmental impact were presented using the standard functional unit for the freight trains: tonne for kilometre (tkm). Additionally, authors have compared two different functional units that could be used in Life cycle assessment of the self-propelled freight railway vehicles, proposing the use of the new functional unit: tonne for working hour (twh). Use of such customized functional unit is more appropriate because of the specific nature of work that selfpropelled bulk carriages have.