In the paper we continue our research on traffic modelling in the Next Generation Network (NGN) architecture, which includes the IP Multimedia Subsystem (IMS) elements. A simulation model of a single NGN domain with transport stratum based on the Multiprotocol Label Switching (MPLS) technology is proposed, which allows evaluation of mean response time of this stratum. The simulation model is applied to verify the results obtained...

In current telecommunications it is assumed that demands of information society for quickly delivered services will be satisfied by Next Generation Network (NGN) architecture, which includes IP Multimedia Subsystem (IMS) elements. To guarantee Quality of Service (QoS), proper design and dimensioning of NGN is absolutely necessary, for which appropriate models have to be proposed. As NGN architecture is very complicated, the most...

The understanding of simulation semantics of a hybrid system is a challenge for computational engineers as it requires expertise in computer science, engineering, numerical methods, and mathematics at once. The testing methods for the execution of a simulation are being researched but not yet applied on the industrial level. Consequently, the semantics of the simulation becomes a critical artifact in the system development process....

Here, variable-fidelity electromagnetic (EM)-based design optimisation of miniaturised antennas is discussed. The authors focus on an appropriate selection of discretisation density of the low-fidelity EM model, which results in good performance of the optimisation algorithm in terms of its computational complexity and reliability. Trust-region gradient search with low-fidelity model corrected by means of non-linear frequency scaling...

This paper presents an energetic model of hydraulic system of a refuse collection vehicle. First, benefits resulting from implementation of an energetic model in the industry and operation of a Refuse Collection Vehicle are briefly explained. Then, components of the energy consumption in hydraulic circuits of compactor and lifting device are described and combined into a comprehensive model that can be evaluated using basic measurement...