Highlights The impact of people's behavior during COVID 19 quarantine on energy consumption was investigated. The study was conducted numerically (using EnergyPlus software) on a specific facility located in the city of Kragujevac during March 2020. Four simulation scenarios were developed to examine the impact of human behavior on energy consumption (natural gas, electricity and water), CO2 emissions and economic analysis in atypical situations, as is the case with the COVID-19 virus pandemic. The protection measures, adopted by the Government of the Republic of Serbia in order to prevent the COVID-19 virus pandemic, have been taken into account. The thesis presents energy and environmental indicators (heat consumption, natural gas consumption, electricity consumption, water consumption and air quality) of the city of Kragujevac for the month of March for the last three years (2018-2020).

This paper presents a comparative analysis of the application of biologically inspired algorithms and methodologies in CAD software packages, for determining the optimal profile values in carriers with two independent variables. As an example of a biologically inspired algorithm to solve this optimization problem, the scroll algorithm was applied, while the SolidWorks software package was used as an example of CAD.

Despite significant improvements in vehicle technology in recent years, vehicle emissions remain a major influencing factor on air quality. Although air quality in the City of Zagreb is still relatively acceptable, official standards, i.e. limiting values are under threat. More than ever, policymakers are actively exploring options for new vehicle emission control and local fleet management policies, as well as the new monitoring technologies to support these activities. The goal of the research was to assess the influence of the introduction of Low Emission Zone on the total emission from the road traffic in the City of Zagreb. To make a model of emissions from road traffic, emissions on selected roads in the City of Zagreb using measured traffic activity data and adequate vehicle fleet characteristics description are calculated. Traffic activity data were obtained from traffic study of the City of Zagreb, while vehicle fleet characteristics are extracted from the database maintained by Center for Vehicles of Croatia and the Ministry of the Interior of the Republic of Croatia. The database contains all the data collected during the homologation process of the vehicles registered in Croatia as well as the data collected during the vehicle periodical technical inspection.