Jasmin Hrnjadović1 Anadel Galamić2 Mufid Tokić3 UDK: 519.6:628.1 DOI: 10.14415/konferencijaGFS2019.074 Summary: The water supply system is a planned and meaningfully connected set of facilities and activities aimed at ensuring sufficient quantity of water in the most economical way. Defining the functional dependence of the hydraulic parameters of the water supply system is crucial because it enables the calculation of unknown values based on the appropriate available or measurable values. „Spline“ interpolation is one of the methods by which it is possible approximately, but with sufficient accuracy, to define the functional dependence of hydraulic parameters if we have known values at certain characteristic intervals that can be measured or calculated by one of the numerical methods. "Spline" interpolation denotes the method of constructing a function within the range of a discrete set, which approximates the already known points. The result is a function, or set of functions, by which it is possible to calculate the value of an unknown function for any value of the variable at a defined interval. The specific application of this method will be shown on the example in this paper.

Paper monitors seasonal dynamics of heavy metals bioaccumulation (Fe, Mn, Cu, Zn and Pb) of emerged plant Phragmites australis (Cav.) Trin. ex Steud. on two localities (Necik and Sinjak) in the area of Bardača fishpond (BiH-Republic of Srpska). Dynamics of heavy metals bioaccumulation varied depending on sampling period, locality and plant organ. Concentration, transfer (transport) and accumulation of metals from sediment to rhizome above ground plant part was evaluated based on biological concentration factor (BCF), translocation ability (TA) and bioaccumulation factor (BAC). The highest average BCF value in researched species was determined for Fe (0.87) and the lowest for Zn (0.18). Bioaccumulation coefficient was the highest for Mn (0.82) and the lowest for Fe (0.20) whereas TA was the highest for Zn (2.28) and Mn (2.70). For Fe, it was significantly lower (0.24). Based on values for BCF, TA and BAC, Phragmites australis (Cav.) Trin. ex Steud. could be identified as accumulator for Mn and indicator for metals Fe, Zn and Cu and it has good potential for application in phytoremediation techniques, especially in phytostabilization and phytoextraction of polluted land. Considering the fact that higher degree of bioaccumulation was recorded in the period at the end of season, we could take this period as a signal for their removal from water ecosystems.

The objective of the study was to explore the barriers or the reasons behind the insufficient use of Web 2.0 technology in companies. The empirical research was conducted among managers in companies in Bosnia and Herzegovina during 2015. The results indicate that managers see information technology infrastructure (department size, technology implementation costs) and computer illiteracy as the main barriers to intensified use of Web 2.0 technology in business. The least relevant obstacles are related to the lack of support from, and the inability to protect the data privacy and integrity in an adequate manner. The results indicate that significant efforts to promote the benefits that Web 2.0 technology brings to the business are needed, which would, in turn, significantly affect the perception of their disadvantages.

This Publication has to be referred as: Cekic, A[hmet]; Muhamedagic, K[enan]; Cohodar, M[aida]; Begic-Hajdarevic, D[erzija] & Biogradlija, S[amra] (2019). Experimental Investigation of Effect of Overhang Tool Length on Tool Vibration and Surface Roughness, Proceedings

Abstract Virtual power plant (VPP) technology aggregates geographically distributed energy resources enabling the management of flexible capacity in the power network on a large scale while implementing local grid constrains. In the smart grid concept, electricity generation and consumption requires the efficient, reliable, and real-time coordination of demand and supply using modern information and communication technologies (ICTs). VPPs enable the inclusion of distributed energy resources into ancillary service provision, typically for load-frequency control. Ancillary services demand reliable communication systems for the exchange of relevant information. This chapter investigates the communication system architecture of VPPs, giving an overview of current communication technologies and communication protocols, which are illustrated with relevant information from selected pilot studies and real deployments. We focus on downstream communication between the VPP and distributed energy resources, and on upstream communication between the VPP, transmission system operator, distribution system operator, electricity market, and retailers. Monitoring quality of service (QoS) parameters enable insights into communication system performance and enable VPP optimization by selecting the most reliable resources for particular services.

Abstract This paper investigates a virtual power plant (VPP) using the OpenADR 2.0b communication protocol to securely and reliably operate distributed energy resources (DERs) over public Internet infrastructure, providing ancillary services to the transmission system operator (TSO). VPP performance analysis was based on an experimental setup as well as a dynamic behavioural model and numerical simulations. The experimental setup consisted of battery stacks from automated guided vehicles at a harbour container terminal. Within this experimental study, we analysed data exchange utilising the OpenADR protocol over a four-week period between the VPP in Slovenia and the terminal management system in Germany by assessing the selected quality of service parameters – latency (round-trip time), packet loss, retransmissions, bandwidth, amount of traffic and message patterns. The impact of latency on performance of the VPP aggregating battery stacks with other DER types was investigated using numerical simulations. Load profiles for the selected DERs and communication channel models were derived from field measurements.