Safety risk management in Bosnian-Herzegovinian underground coal mines is not based on a systematic approach and standardized risk management methods. Mostly there is a traditional approach present, i.e. reaction to incidents/accidents that happen. This paper aims to point out the need for proactive approach introduction with an emphasis on importance of ventilation systems failure mechanism simulation analysis in planning of people and property defense and rescue in crisis situations. Based on ventilation parameters measuring results for a given research site (brown coal mine), a model was developed on which a simulation analysis was performed for three characteristic ventilation failure cases: spontaneous oxidation at the longwall exit, collapse at the entrance to the longwall and methane outburst - preparation of a new excavation field. VnetPC and CFD “Fluent” software packages were used to simulate mine ventilation. Keywords: risk management, brown coal mine, safety, ventilation system, longwall, simulation analysis, VnetPC, Fluent.

Abstract Phase unbalance is a common issue encountered in LV electricity distribution networks, caused by uneven allocation of single-phase loads among phases. This paper analyses a part of a real LV distribution network, situated in Bosnia and Herzegovina. The impact of single-phase customers and single-phase charging of electric vehicles was analysed. To reduce unbalance and improve the voltage profiles, Phase Balance Optimization in DIgSILENT PowerFactory software was performed in six scenarios with different customer and electric vehicle unbalance. The goal was to find a method with the least number of changes in the customer and electric vehicle phase connection that fits within defined limits of voltage variations and voltage unbalance of a European norm for power quality (EN 50160). Results showed that all analysed scenarios were improved, with reference to voltage variation and voltage unbalance values, and were found acceptable by the limits from standard EN 50160.

Abstract In the past couple of years, the integration of electrical vehicles (EV) in the power system has been capturing the attention of many researchers, which has led to this being a frequently analysed topic in scientific papers and seminars. Some of the main parameters related to power quality that are observed, while integrating EVs, are voltage variations and voltage unbalance. The low-voltage rural network, of a small settlement located on the outskirts of Zavidovici, has been modelled for the purpose of this paper. Several cases were considered. As the first base case, an analysis was performed when there were no connected vehicles in the network, then the case with 20% penetration, 35% penetration, and 80% vehicle penetration. Practical analysis was done in DIgSILENT Power Factory software. It has been concluded that electrical vehicles cause a voltage drop in the network, while at the same time causing an increase in voltage unbalances.

In the present study, vortex-assisted matrix solid-phase dispersion (VA-MSPD) extraction was used to isolate the major bioactive compounds from H. arenarium. To reduce the negative environmental impact of the conventionally used organic solvents, four different choline chloride-based natural deep eutectic solvents (NADES) were investigated as possible eluents. The most influential VA-MSPD extraction parameters: stationary phase (adsorbent), adsorbent/sample ratio, vortex time, and volume of extraction solvent were systematically optimized. Ultrasound-assisted extraction with 80% MeOH was used as the standard method for the comparison of results. The stability of the obtained extracts was studied over a period of 0 to 60 days at three different temperatures (−18 °C, 4 °C, and 25 °C). All extracts were evaluated both spectrophotometrically (determination of total phenolic content (TPC) and antioxidant activity by ABTS and FRAP assay) and chromatographically (HPLC-UV). NADES based on choline chloride and lactic acid (ChCl-LA) was selected as the most effective extractant, with a determined TPC value of its extract of 38.34 ± 0.09 mg GA/g DW (27% higher than the methanolic VA-MSPD extract) and high antioxidant activity. The content of individual phenolic compounds (chlorogenic acid, dicaffeoylquinic acid isomers, naringenin isomers, and chalcones) in the ChCl-LA extract, determined by HPLC-UV, was comparable to that of the conventionally obtained one. Moreover, the stabilization effect of ChCl-LA was confirmed for the studied compounds: chlorogenic acid, naringenin-4′-O-glucoside, tomoroside A, naringenin-5-O-glucoside, isosalipurposide, and naringenin. The optimum VA-MSPD conditions for the extraction of H. arenarium polyphenols were: florisil/sample ratio of 0.5/1, a vortex time of 2 min, and an elution volume of ChCl-LA of 10 mL.

This study analyzed 16 bisphenols (BPs) in wastewater and sludge samples collected from different stages at a municipal wastewater treatment plant based on sequencing batch reactor technology. It also describes developing an analytical method for determining BPs in the solid phase of activated sludge based on solid-phase extraction and gas chromatography-mass spectrometry. Obtained concentrations are converted into mass flows, and the biodegradation of BPs and adsorption to primary and secondary sludge are determined. Ten of the sixteen BPs were present in the influent with concentrations up to 434 ng L−1 (BPS). Only five BPs with concentrations up to 79 ng L−1 (BPA) were determined in the plant effluent, accounting for 8 % of the total BPs determined in the influent. Eleven per cent of the total BPs were adsorbed on primary and secondary sludge. Overall, BPs biodegradation efficiency was 81%. The highest daily emissions via effluent release (1.48 g day−1) and sludge disposal (4.63 g day−1) were for BPA, while total emissions reached 2 g day−1 via effluent and 6 g day−1 via sludge disposal. The data show that the concentrations of BPs in sludge are not negligible, and their environmental emissions should be monitored and further studied.

In the present-day environment pertaining to digitalisation, increasing competition on the market and changes in industries, the CRM as a system is an essential tool for success. The issue of CRM system application in higher education institutions is insufficiently researched, especially in the parts that should indicate a clear connection between participants in higher education and CRM in higher education institutions, and factors that decision makers should pay attention to when making decisions about CRM implementation. Therefore, the aim of the paper is to research the functionality, application and advantages of CRM in the higher education sector, and to determine the features that will facilitate effective decision-making on the implementation of CRM. As a result of the research, a proposal for a conceptual model/framework of CRM was presented. The proposal is presented for the purpose of making appropriate decisions for higher education institutions when it comes to developing their own or purchasing a ready-made CRM solution. From the scientific aspect, the paper contributes to the existing literature by providing decision makers with an insight into the structure of the CRM system, its elements, connections and functionalities, as well as a description of the model with the information they need to pay attention to when making decisions.

Abstract The subject of this paper are the diary no- tes of the Bavarian botanist Otto Sendtner published in the German magazine "Das Ausland" regarding the medieval fortress of Srebrenik and the tradition about its fall under the Ottoman rule, which were completely unknown in the literature. This Munich university professor stayed in the Bosnian ejalet/Province in 1847, and on that occasion, he visited a significant number of cities, starting with Split, Livno and Travnik as the main destination. From the vizier's city and the seat of Ejalet, he went to Bosanska Posavina due to his botanical research, and on that occasion he passed through Srebrenik. Sendtner wrote in detail about the fortress, inspired by its features, and also left a note of local folklore tradition regarding its fall under the Ottomans, which deserves special attention. Also, in Send- tner's exposition, romantic narratives and orientalism ele-ments can be observed in the descriptions of the Srebrenik fortress and the landscape surrounding it, which can be attributed to the features of the imagi- nation about the Middle Ages presented in the European intellectual circles during the middle of the 19th century. Keywords Srebrenik, Bosnia, Middle Ages, oral tradition, travelogue, Otto Sendtner

Ensuring safety is of paramount importance in physical human-robot interaction applications. This requires both adherence to safety constraints defined on the system state, as well as guaranteeing compliant behavior of the robot. If the underlying dynamical system is known exactly, the former can be addressed with the help of control barrier functions. The incorporation of elastic actuators in the robot's mechanical design can address the latter requirement. However, this elasticity can increase the complexity of the resulting system, leading to unmodeled dynamics, such that control barrier functions cannot directly ensure safety. In this paper, we mitigate this issue by learning the unknown dynamics using Gaussian process regression. By employing the model in a feedback linearizing control law, the safety conditions resulting from control barrier functions can be robustified to take into account model errors, while remaining feasible. In order to enforce them on-line, we formulate the derived safety conditions in the form of a second-order cone program. We demonstrate our proposed approach with simulations on a two-degree-of-freedom planar robot with elastic joints.

The asphalt layer is an important financial part of the total cost of road infrastructure, so it is necessary to analyze and consider all the elements that may affect the quality of the same. One of them is certainly the influence of temperature during the installation of asphalt mass. Namely, neither high nor low temperature of asphalt and the environment are favorable for its installation, so it is necessary to find optimal conditions for the installation of asphalt in order to achieve the best possible results of compaction and cavities in the asphalt layer. The aim of this research is to find the optimal conditions for its installation by comparative analyzes of different temperatures of the asphalt mixture and the environment, in order to obtain the lowest percentage of cavities in the asphalt layer. The legal regulations, ie technical conditions, define the minimum temperature of the asphalt mixture as well as the limit air temperature during the installation of asphalt, but special emphasis is placed on the impact of the temperature of the asphalt installation on the cavities in the asphalt layer. Therefore, the paper observes the optimal temperature of the asphalt mixture so that the smallest possible percentage of cavities in the asphalt layer is obtained. Keywords: asphalt mixture temperature, installation, cavities

In this paper, it was necessary to prove that Semberija is in the geomorphological sense, the southern part of the Pannonian Basin, which is in contact with the Dinaric mountain system. Its done on the basis of the geo- morphological analysis of the terrain, primarily morphotectonic, morphological and morphogenetic similarities with the plain terrain of Pannonia. This was the basis for a complex geomorphological regionalization which included added similarities and connections with the Pannonian Basin in climate, pedogeography and biogeog- raphy sense. Thus, after the complex geomorphological regionalization, it was determined that Semberija is a meso-entity, a subunit of the geomorphological macroregion Sava Basin, ie the southernmost part of the geo- morphological megaregion Pannonian Basin. Key words: Complexed geomorphological regionalization, geomorphological meso-entity Semberija lowland plain, Pannonian Basin, Bosnia and Herzegovina.