The assessment and prediction of temporal variations in surface water quality-a case study.

In order to optimize the processes of sampling, monitoring, and management, the initial aim of this paper was to develop a model for the definition and prediction of temporal changes of water quality. In the case of the Morava River Basin (Serbia), the patterns of temporal changes have been recognized by applying different multivariate statistical techniques. The results of the conducted cluster analysis are the indicators of the existence of the three monitoring periods: the low-water, transitional, and high-water periods, which is in accordance with changes in the water flow in the analyzed river basin. A possibility of reducing the initial data set and recognizing the main pollution sources was examined by carrying out the principal component/factor analysis. The results indicate that the natural factor has a dominant influence in temporal groups. In order to recognize the discriminatory water quality parameters, a discriminant analysis (DA) was carried out. Conducting the DA enabled a significant reduction in the data set by the extraction of two parameters (the water temperature and electrical conductivity). Furthermore, the artificial neural network technique was used for testing the possibility of predicting changes in the values of the discriminant factors in the monitoring periods. The reliability of this method for the prediction of temporal variations of both extracted parameters within all temporal clusters has been proven.

Evaluation of the ecochemical status of the Danube in Serbia in terms of water quality parameters.

The Danube is an international river passing partly through Serbia. The protection of the environment and sustainable use of water resources is a primary task that implies constant monitoring of the quality status and evaluation of ecochemical status of the water in the Danube basin. The investigation includes calculation of all-inclusive water quality by the Serbian water quality index (SWQI) method and an evaluation of eco-chemical status of the Danube water in terms of water quality parameters from the entry to the exit point along its course through Serbia in the year of 2009. The results show that the overall quality of the Danube water on the territory of Serbia corresponds to the descriptive indicator of "very good" water. According to the Council Directive75/440/EEC, the evaluation of the ecostatus, with slight deviation of individual parameters at Pancevo, corresponds to A1 category of the surface water quality intended for the abstraction of drinking water supplies in member states.

The relationship between ethical leadership, organizational commitment and Zero Accident Vision implementation in the defense industry.

The main aim of this research was to measure workers' perceptions of the four crucial success factors (commitment to safety, safety communication, the safety climate and learning from incidents) for Zero Accident Vision (ZAV) implementation by conducting a survey using a questionnaire given to four production plants in the Serbian military industrial complex. Almost 500 respondents participated in this survey with a response rate of over 90%. A possible influence of ethical leadership at work (ELW) and organizational commitment (OC) on ZAV enforcement was also examined. The reliability and validity of all of the measuring instruments were found to be acceptable. ELW was found to have a strong influence on ZAV implementation, whereas OC was found to have the mediating role in this relationship.