No abstract

In practice of loading of oil-immersed distribution transformers, there is a need to have lumped thermal model, requiring no big computational resources and computational time. One such model is presented in international transformer loading guide (IEC 60076-7), where heat transfer inside the transformer is modeled. In case of indoor transformer operation, this model does not consider transient thermal phenomena in the room. We developed a lumped model that includes heat transfer in the transformer room. In scope of the research, we also built FEM CFD (finite element method, computational fluid dynamics) model of air flow and heat transfer. The purpose of FEM CFD was to make a better insight into air flow, i.e. to study the simplifications introduced in lumped model and suggest potential improvements. This paper presents results achieved with FEM CFD. The considered case was the transformer with natural oil and natural air flow (ONAN).

some machine learning algorithms for sex identification based on linear mandibular measurements derived from CT scans .

No abstract

The paper presents an innovated hardware and software platform for the implementation of the fuzzy controller fortemperature and temperature slope change in an electric resistance chamber furnace. The point of this paper is to present the modernhardware and software tools that we used to lift up the base for continuation of the research done in the laboratory for electricalheating of Faculty of electrical engineering, University of Belgrade, more than 15 years ago. In that period, also the robustness ofcontrol in respect to the amount of load in the furnace was investigated. This paper focuses to the further investigation of therobustness. More precisely, experiments were performed to study if the controller can be applied as "plug and play controller", i.e. ifthe controller can be applied without additional tuning on another furnace with the similar construction in respect to the one where thefuzzy controller is tuned. The tests on two electric chamber furnaces with different rated power and volumes confirm the "plug andplay controller" principal is realistic.