Hybrid systems, which were created by integrating the structural systems of different behavior in the transfer of loads, represent a new efficient system, with low self-weight, increased capacity characteristics and reduced deformability compared to the systems of which they are made of. Applicable to all materialization and logical geometric forms, they represent transparent systems suitable for optimization of structures. In this paper is represented the original analysis of parameters, reduced to relative values of a hybrid system with and without pre-stressing of different geometric shapes, particularly in terms of deformability. The results of the research are represented through the practical expressions and diagrams for use in practice, and on the basis of which can be determined suitable constellation of system from a simple girder, strut type hybrid system with different geometrical characteristics and pre-stressed hybrid system, and in the case of wood-steel hybrid system for different percentage of moisture of wood girder. To give access presents the accurate method that can be applied to any combination of materials in the context of a hybrid system.

Professional paper The basic aim of this paper is to estimate possible hazards at casting machines under high pressure in production conditions, by failure modes and effect analysis (FMEA) method. Providing high reliability, safeness and quality in the use of any technical system (TS), is a complex task for designers, engineers, technologists in the process of production and maintenance. The example, shown in the paper (casting machines under high pressure), can be used for the analysis of the reliability in the design phase and in the exploitation period of many processes in the machine industry. For this purpose an "adjusted" (simplified) procedure for failure analysis has been developed. Analysis was conducted in the production conditions in the factory FAM Secanj, Serbia. In the paper, we evaluated the failure at four casting machines by using FMEA method and by using FMEA Worksheets according to standard SRPS EN 60812:2011. Based on the RPN value (Risk Priority Number) certain corrective actions have been implemented. By application of these actions, it is possible to predict the maintenance procedures of the system in order to provide the required reliability during operation of the system.

Due to the increased use of fossil fuels and industrial production, the concentration of carbon dioxide in the atmosphere increases, causing greenhouse effect and, consequently, climate change. Stationary CO2 sources like coal power plants produce the bulk of the world’s CO2 emissions. Electricity and heat plants and other fuel transformation activities account for 40% of total global CO2 emissions. Therefore, great interest in the possibilities of CCS systems to reduce CO2 emission is evident, either through removal or reduction measures. The experimental part of this paper deals with the determination of the potential of alternative media for use in CCS technologies, describing the lab-scale investigation. The role of alternative media in that context has been assigned to recurrent water from fly ash and slag disposal pond Jezero II of Power Plant Tuzla. When choosing an alternative medium for CCS applications, the following features were considered: that the medium currently has a negative impact on the environment; that the medium is available in sufficient quantities; that the medium has a low price and that its final disposal causes costs. Hence, the ability of the selected media (recurrent water) for CO2 capture has been confirmed and its capacity in that context roughly determined.