Mathematical models to determine the influence of road parameters and conditions on vehicular speed

Abstract The study of vehicular movement modes in adverse weather conditions allowed defining the dependence of traffic modes at certain road segments on weather conditions. It is found that the average vehicle speed changes within a year over a wide range depending on road conditions even on its straight horizontal sections. There is a considerable difference in the maximum speed of traffic movement. Complex road sections significantly influence the traffic mode during any period of the year, especially in adverse weather conditions. The road surface condition exerts the greatest impact on the traffic speed. If the adhesion coefficient equals 0.2-0.3 the average traffic speed is 20-25% lower than if that adhesion coefficient equals 0.5-0.6, and in ice conditions the average traffic speed decreases by 40-50%. The proposed calculation formula allows defining the influence of weather conditions on the traffic mode of free-moving cars or cars in a joint traffic flow. It provides for the feasibility study regarding measures aimed to increase the traffic speed in adverse weather conditions of the year. Based on the observations and calculations the correlation dependences of average and maximum traffic speeds on the adhesion coefficient within a 7.0 m-wide road without the hard shoulder were obtained.</jats:p

Analysis of modern wood processing techniques in timber terminals

The transportation of forestry products is performed over long distances and is quite expensive, which limits the development of biofuel plants in Russia and around the world. The use of timber terminals contributes to transportation cost reduction and mitigates negative environmental impacts. This work aims to analyze various technological solutions for optimization of forestry products processing at temporary terminals and cost reduction of transportation, shipping, and wood treatment. The work presents a discussion on the technological and economic possibilities of the mobile pellet plant, the mobile essential oil production plant, and an enhanced autonomous electric generator system. It is shown that the use of mobile plants for obtaining pellets and essential oils allows processing wood residues at the terminal, which reduces the cost of transportation and shipment of raw materials and improves the quality of the finished products. The current study also examines some of the modern scanning technologies used to detect log defects and obtain complete biometric information in real time while assessing the productivity of wood processing operations. The results of the study can be used to develop efficient movable timber terminals. © 2022 Oľga Kunickaya et al., published by Sciendo