The aim of the research presented here is to design and implement a system for automatic production of copper wire, by the method of up-casting. The subsystem for induction heating includes automatic control of the temperature of the melted as well as annealed copper, automatic regulation of the induction heating power. The induction coil was designed and made to provide proper heating of the copper wire that is produced, so that the necessary temperature can be reached and its annealing or melting obtained. The coil is made of copper tube and its temperature is regulated using forced oil flow through the tube. The system can be easily adapted to be used in automation of the process of steel wire or iron wire annealing, having in mind the electrical and magnetic properties of the steel and iron. The system was produced, tested and put to work.

High-frequency wood drying is the modern method used in raw wood drying so that treated wood can be used further in various processes. Such systems are used because of the economy, energy efficiency, obtaining of good mechanical properties of the wood after treatment, as well as reducing time consumption. Therefore, it is extremely important to understand each component of such systems and processes. The mentioned systems are implemented using high-frequency generators based on vacuum tubes (VT). Their development and, in particular, optimization are by far more complex than the transistor systems; therefore, the development is now compelled to rely on computer modelling and simulation. In this research, a high-frequency (HF) generator of 20 kW output power and 1.5–15 MHz adjustable frequency based on VT was produced and then, with the corresponding model for VT itself and the rest of the developed circuit, was followed by computer simulation and real-system measurement. The model parameters were adjusted, which provided additional system optimization. An extra match of the results from the simulation and measurement was obtained; thus, the optimization was performed faster and more precisely. In addition, an easier and quicker way of adjusting parameters of the PID controller using a developed software-based control system was attained. The problems of cooling the VT anode under high DC voltage, as well as temperature measurement in the HF electric field, have been solved.

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Cilj ovog rada je da se ispita primena LabVIEW programskog paketa za kontrolu i praćenje procesa rada uređaja, stanice za prekuglavanje BGA (eng. Ball Grid Array) čipova. Proces prekuglavanja je složen proces i obuhvata više faza. Uređaj je konstruisan u Boru, izvršeno je njegovo testiranje i utvrđene su njegove osnovne karakteristike.

Although the most prominent material in contemporary construction practice due to its obvious advantages, concrete possesses a number of drawbacks. One of the advantageous principles for decades is to enable a large scale on-site application of this material with acceptable properties, needed to withstand specific conditions. A concept of 3d printing concrete presents a promising ground for further improvement of this principle. While maintaining as much as possible of the prerequisite and common properties to answer the construction demands, this material has to evolve as much as possible to fulfill the 3d concept, which would, in turn, pave a way for the next level of its construction applications. This paper presents the main principles of 3d printing concrete, by discussing the main goals and the drawbacks that have to be solved prior to wider application. Also, one specific facility- wind tower will be reconsidered as a potentially promising ground for this old construction material dressed in a new suit.