THE IMPACT OF VEHICLES ON AIR QUALITY IN ZAGREB AND KOROMAČNO, CROATIA

This paper describes and analyses concentrations of main traffic related air pollutants and their impact on air quality, which affects the quality of human life. The data are obtained from the measuring stations in Zagreb and Koromačno (Croatia). These two places were chosen because of their diversity, related to traffic density – Zagreb is capital of Croatia, and Koromačno is a small town in Istria region. Due to a specific way of pollution assessment, the data are presented in diagrams using an application, designed for this purpose, which enables easy comparisons and interpretation of the data. The results of this research indicate specific patterns of changes in the pollutant concentrations in relation to emissions of road motor vehicles

The Relevance of GHG Emissions from Motor Vehicles

The Earth\u27s atmosphere contains not more than 2% of greenhouse gases (GHG), and only 3.4% of them are produced by human activities. GHG emissions from road transport amount to less than 0.3 % of global GHG emissions. In spite of that, even in the Kyoto Protocol, road transport is pointed out as one of the most important targets when the global GHG emission reduction is concerned. In April 2009, the European Commission adopted the regulation (EC) 443/2009, setting CO2 emission performance standards for new passenger cars. The paper briefly describes the global economic impact of the Kyoto Protocol on developing countries. Then, total GHG emissions of various types of vehicles are reviewed, and the emerging vehicle technologies, focusing on reducing GHG emissions and replacing fossil fuels with alternative energy resources, are discussed. A well-to-wheel (WTW) analysis of a midsize electric car operating in Croatia has been carried out in the case study. Finally, the main conclusions are drawn: further reduction in GHG emissions from road transport would result in marginal global effects and, compared to all new power train systems, internal combustion engine running on fossil fuels still has great potential for further improvements thus remaining the most viable solution for the future

Analysis of out-of-hospital cardiac arrest in Croatia – survival, bystander cardiopulmonary resuscitation, and impact of physician’s experience on cardiac arrest management: a single center observational study

Aim To analyze the initial rhythm, bystander cardiopulmonary resuscitation (CPR) rate, and survival after out-of-hospital cardiac arrests (OHCA) in Varaždin County (Croatia), and to investigate whether physician’s inexperience in emergency medical services (EMS) has an impact on resuscitation management. Methods We reviewed clinical records and Revised Utstein cardiac arrest forms of all out-of-hospital resuscitations performed by EMS Varaždin (EMSVz), Croatia, from 2007-2013. To analyze the impact of physician’s inexperience in EMS (<1 year in EMS) on resuscitation management, we assessed physician’s turnover in EMSVz, as well as OHCA survival, airway management, and adherence to resuscitation guidelines in regard to physician’s EMS experience. Results Of 276 patients (median age 68 years, interquartile range [IQR] 16; 198 male; 37% ventricular fibrillation/ventricular tachycardia, bystander CPR rate 25%), 80 were transferred to hospital and 39 were discharged (median survival after discharge 23 months, IQR 46 months). During the 7-year study period, 29 newly graduated physicians inexperienced in EMS started to work in EMSVz (performing 77 resuscitations), while 48% of them stayed for less than one year. Airway management depended on physician’s EMS experience (P = 0.018): inexperienced physicians performed bag-valve-mask ventilation (BMV) more than the experienced, with no impact on survival rate. Physician’s EMS experience did not influence adherence to resuscitation guidelines (P = 0.668), survival to hospital discharge (P = 0.791), or survival time (P = 0.405). Conclusion OHCA survival rate of EMSVz resuscitations was higher than in Europe, but bystander CPR needs to be improved. Compared to experienced physicians, inexperienced physicians preferred BMV over intubation, but with similar adherence to resuscitation guidelines and survival after OHCA

Multi-objective optimization model in the vehicle suspension system development process

U cilju unapređenja konceptualne faze razvoja vozila, ovo istraživanje je usmjereno na razvoj novog višekriterijskog optimizacijskog modela za određivanje optimalnih parametara ovjesa vozila. U ovom istraživanju naglasak je na razvoju ovjesa vozila promatrano kroz dinamičko ponašanje kompletnog vozila. Novi optimizacijski model temelji se na integraciji brzih simulacijskih alata s zadovoljavajućom razinom točnosti za analizu kinematike ovjesa i dinamiku vozila unutar okruženja za višekriterijsko optimiranje. Nužni koraci koji prethode razvoju optimizacijskog modela su identifikacija utjecajnih parametara, definiranje kriterija za ocjenu dinamičkih karakteristika vozila u različitim ispitnim procedurama i odabir višekriterijskih optimizacijskih algoritama, prvenstveno suvremenih evolucijskih algoritama. Usporedba optimizacijskih algoritama pokazala je da se najbolji rezultati u pogledu konvergencije, broja mogućih rješenja, trajanja računanja i približavanja Pareto fronti postižu s FMOGA-II algoritmom.In order to improve conceptual phase of vehicle development, this research is focused on development of new multi-objective optimization model for determining the optimal parameters of the suspension system. In this research emphasis is on the development of suspension system from the viewpoint of full vehicle dynamics behaviour. The new optimization model consists of the integration of fast simulation tools with a suitable degree of accuracy for analysis of suspension system kinematics and analysis of vehicle dynamics into multi-objective optimization environment. The necessary steps that proceed to development of optimization model are identification of influence parameters, definition of criteria for the evaluation of vehicle dynamic characteristics in different test procedures and selection of multi-objective optimization algorithms, primarily contemporary evolutionary algorithms. In comparison of the algorithms, the best results in terms of convergence, number of solutions, short computing time and Pareto front approximation were achieved with the FMOGA-II algorithm

Višekriterijski optimizacijski model u razvoju ovjesa vozila

U cilju unapređenja konceptualne faze razvoja vozila, ovo istraživanje je usmjereno na razvoj novog višekriterijskog optimizacijskog modela za određivanje optimalnih parametara ovjesa vozila. U ovom istraživanju naglasak je na razvoju ovjesa vozila promatrano kroz dinamičko ponašanje kompletnog vozila. Novi optimizacijski model temelji se na integraciji brzih simulacijskih alata s zadovoljavajućom razinom točnosti za analizu kinematike ovjesa i dinamiku vozila unutar okruženja za višekriterijsko optimiranje. Nužni koraci koji prethode razvoju optimizacijskog modela su identifikacija utjecajnih parametara, definiranje kriterija za ocjenu dinamičkih karakteristika vozila u različitim ispitnim procedurama i odabir višekriterijskih optimizacijskih algoritama, prvenstveno suvremenih evolucijskih algoritama. Usporedba optimizacijskih algoritama pokazala je da se najbolji rezultati u pogledu konvergencije, broja mogućih rješenja, trajanja računanja i približavanja Pareto fronti postižu s FMOGA-II algoritmom

Model for Calculating Average Vehicle Mileage for Different Vehicle Classes Based on Real Data: A Case Study of Croatia

Mileage data collected via surveys based on self-estimation, reports from garages and other sources which use estimations are rough estimates and differ greatly from the actual mileage. Vehicle mileage is a major factor in emission calculations and needs to be as accurate as possible to obtain reliable emission models. Odometer readings are collected annually at the periodic technical inspection in Croatia. Average mileage data were analyzed for vehicles up to 20 years of age in 2017. Vehicles were classified by curb weight and fuel type. Such classification proved to follow driver behavior and the intended purpose of the vehicle. For each vehicle class, the model was applied using the vehicle age and its population size as inputs for calculating average mileage. Real data shows that vehicles in Croatia considerably exceed the estimated mileage in the years following the first registration of the vehicle and that they cannot be compared to data collected in other studies based on estimations. The difference lies in the covered mileage after vehicles reach ten years of age. The outcome of this study has resulted in a model for calculating average vehicle mileage. The model is suitable for use in various analyses for Croatia or for countries with similar driving habits and economic status now and for years to come

RETROFIT OF A ROLLER BRAKE TESTER AT FAMENA

The vehicle brake tester described in this paper is placed in the Laboratory for IC Engines and Motor Vehicles at the Faculty of Mechanical Engineering and Naval Architecture (FAMENA) in Zagreb. As the device, built in 1983, was inoperative, a decision was made for retrofit rather than repair. The retrofit included a reconstruction of some parts and modification of the braking force measurement. Adaptation of monitoring and control was made on electronic components that control the roller set during the manual and the automatic operation. Using the LabVIEW programming software, our team created a computer program for monitoring the positioning of a vehicle on the device, the measuring of vehicle mass needed for the calculation of braking coefficient, the control of operating mode (automatic or manual) and the start/stop mode of electro motors inside the device