ABSTRACT:Harvester technologies represent the second most common logging system in the Czech Republic. The high productivity of this technology is very necessary to cover its acquisition and operational costs. A human factor -a machine operator is the most important factor that surely influences the machine productivity. That is why the aim of this study is as follows: to analyze the mutual dependence of machine operator's education and working experience and harvester and forwarder productivity. The analysis proves that the operator's education and even more his working experience are very important. The time of harvesting work stages was measured when the harvester was operated by an operator with two-year working experience and by an operator with no experience. The average time difference between the harvester operators was 64.9 seconds in one work stage. The statistical significance of different operation times was confirmed during technically demanding segments in the working stage (the boom out the felling head and tree processing). Operators with the same working experience in forestry mechanization -about 13 years but with different education carried out the haulage work stage. In this case, the statistical significance between calculated differences was not proved. This fact proves that the operator's working experience is more important than his education.

Accident statistics show that a collision of a train with a car has a significant share of the number of traffic accidents. It also ranks among the most tragic. Three crash tests were made simulating the side impact of a railway vehicle with a car on a level crossing to monitor the biomechanics of possible injury. This study pays particular attention to head injuries. Head acceleration in all three axes was captured on a mannequin during an impact with Skoda Superb and Skoda Favorit vehicles. The most common head injury criterion (HIC) was selected as a quantitative indicator for comparison. It transpired that the contact of the head with an element of the car interior, whether or not the out-of-position occurs during the impact, plays an important role in the severity of head injuries.

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