Table of Contents

  • TRANSPORT TECHNICS. INVESTIGATION OF ELEMENTS. RELIABILITY

    • Influence of non-metallic inclusions and products of corrosion on the wear particles formation on the railway wheel and rail treads

      pg(s) 96-101

      The effect of inclusions and corrosion products on the mechanism of wear of railway wheels made of R7 steel and also of rails made of R7 steel M76. was studied. The research was carried out by several methods: metallographic, electron microscopy, X-ray, micro-X-ray spectral analysis. The features of the formation of wear particles near nonmetallic inclusions and corrosion products related to structural changes near the treads of railway wheels and rails as well as to the interaction of steel with the surrounding atmosphere during operation were investigated. The influence of various factors on the role of nonmetallic inclusions and corrosion products in the formation of wear particles is shown, which makes it possible to predict the nature of wear of the rolling surface of railway wheels and rails under various operating conditions. The main sources and the mutual influence of various factors on the formation of wear particles near nonmetallic inclusions and corrosion products have been established, which makes it possible to predict the nature of wear of the rolling surface of railway wheels and rails under various operating conditions.

    • Characteristics of the materials used in the design of unmanned aircraft aircraft type

      pg(s) 101-104

      The use of aircraft-type unmanned aerial vehicles (UAVs) is considered. The advantages, disadvantages and limitations of specific configurations of the UAV body are described. The requirements for simultaneous assessment of materials are described, with an emphasis on modern composite materials forming structurally reinforced or three-layer structures of some UAV elements. It is proposed to take the mass efficiency coefficient of the model as a basis for comparison of aircraft-type UAVs, which determines what part of the mass of the considered design corresponds to the requirements of users. A static analysis of the fuselage and wings of aircraft-type UAVs, made with new materials, was carried out, determining the parameters and their shapes in order to reduce the bending moment acting on the structural elements of the wing, which would reduce its weight. Safety coefficients for the operation of aircraft-type UAVs with certain materials and the financial situation in their design based on forecasting time series of changes in the requirements for the use of UAVs are proposed.

  • TRANSPORT. SAFETY AND ECOLOGY. LOGISTICS AND MANAGEMENT

    • Eco-Efficiency and Service Quality as Dual Drivers of Competitiveness in Liberalized Suburban Rail Transport

      pg(s) 105-107

      The liberalisation of European passenger rail markets under the EU’s Fourth Railway Package confronts suburban rail operators with a fundamentally new competitive environment. Where incumbents once operated under protected concessions, they now face the prospect of open-access competition and competitive tendering. This paper proposes a two-dimensional model of competitiveness centred on eco-efficiency and service quality — treated not as independent performance metrics, but as mutually reinforcing drivers of long-term market position. Eco-efficiency is defined as the ratio of transport output, measured in passenger-kilometres, to the energy and resource inputs required to achieve it, including CO₂ emissions. Service quality is assessed across five dimensions: reliability, passenger comfort, rolling-stock condition, accessibility, and the onboard environment. Drawing on European comparative practice and a focused analysis of the Plovdiv–Karlovo suburban corridor in Bulgaria, the paper demonstrates that these two dimensions operate in a relationship of synergy. Modern, energy-efficient rolling stock improves the passenger experience and raises load factors, which in turn yields further gains in eco-efficiency. The corridor analysis illustrates both the potential and the current constraints facing operators in a post-socialist railway context.
      An examination of existing Public Service Obligation (PSO) frameworks reveals a structural misalignment: current subsidy schemes are oriented predominantly toward maintaining geographic service coverage, rather than rewarding environmentally efficient and high-quality delivery. This creates an incentive structure that may discourage investment in precisely the capabilities that would enhance competitiveness under liberalisation. The paper concludes with targeted recommendations for reorienting performance indicators and funding mechanisms toward the proposed dual-driver model, with the aim of placing suburban rail development on a more sustainable and competitive footing.

    • Macrosimulation-based evaluation of a planned urban arterial: the extended branimirova street in sesvete, Zagreb

      pg(s) 108-110

      Zagrebačka Road is the most heavily loaded corridor in Sesvete, the easternmost district of Zagreb, Croatia, and the city’s planning documents foresee the extended Branimirova Street as a second longitudinal to relieve it. This paper evaluates the conceptual design of that arterial with a calibrated macroscopic model. Morning-peak origin–destination demand was obtained from unmanned-aerial-vehicle traffic counts at five key intersections and assigned in a PTV Visum subnetwork calibrated against the counts (R² = 0.91). Two design variants were tested under identical demand: one following the General Urban Plan and one with two additional junctions. Both reduce the daily volume on Zagrebačka Road by about 22–23% and attract 12000–15000 vehicles per day to the new corridor, while the second adds only local benefit. Fuel use and CO₂ fall correspondingly on the relieved corridor.

  • VEHICLE ENGINES. APPLICATION OF FUELS TYPES. EFFICIENCY