In an era of increased scarcity of resources and pollution, the concept of the circular economy is re-emerging to steer supply chains towards more sustainable business practices. The potential of value recovery provides opportunities for the creation of circular supply chains. Reverse flows and value recovery processes are scarcely studied in the context of fresh food supply chains. In this paper, we report findings from an empirical study of three fresh food supply chain networks by considering: product residual value, quantities available for recovery, value from recovery and markets for recovered products. We show that (1) financial value from recovery is a necessary condition for profitability of operations of any value recovery process in fresh food supply chains, but not for the occurrence of the corresponding loop itself; (2) reuse and remanufacturing loops likely feed into alternative markets, while recycling loops likely feed back into fresh food supply chains.
Reducing CO2 emission is one of the major environmental challenges for transportation. One way to solve this problem is to replace old cars that use fossil fuels (petrol, diesel) with new electric cars. In this paper, the existing model for calculating well-to-wheels CO2 emission during the life cycle of the car (fossil fuel car and electric car) is upgraded. The developed model is used for comparing optimal lifetime and optimal car?s kilometers driven during a lifetime in the replacement process of a fossil fuel car with a new electric car. We find that reducing CO2 emission depends on the type of fossil fuel, and the weight of fossil fuel cars and electric cars. Changing petrol fossil fuel cars with lower weight electric cars have the greatest potential for reducing CO2 emission. However, the introduction of electric cars does not achieve a significant reduction of CO2 emission in countries where electricity is primarily produced in thermal power plants, i. e. in countries with a high emission factor of electricity production.
Transport represents an industry sector with intense energy consumption, the road transport sector within is the dominant subsector. The objective of the research presented in this paper is in defining the activities which applied within road freight transport companies contribute to enhancing vehicles’ energy efficiency. Vehicle fleet operation management process effects on fuel consumption decrease have been looked into. Operation parameters that influence vehicle fuel consumption were analyzed. In this sense, a survey has been realized in order to evaluate the vehicle load factor impact on the specific fuel consumption. Measures for enhancing vehicle’s logistics efficiency have been defined. As a tool for those measures’ implementation an algorithm for vehicle fleet operation management was developed which represented a basis for a dedicated software package development for vehicle dispatching process decision support. A set of measures has been recommended and their effects in fuel savings were evaluated.
The paper deals with the problem of a dynamic analysis of truck-cranes. Therefore, the article has developed a mechanical-mathematical model having 18 generalized coordinates. Depending on the type of truck crane operation as well as on the fact whether the aim of the article is to conduct the dynamic analysis of the whole truck crane or only that of one of its components, simpler mechanical models are also offered. The presented model is more realistic than those describing the dynamic behaviour of the truck-crane performing all necessary functions, i.e. a mobile means of lifting, transportation and reloading.