Лесотехнически Университет

Summary

Wood machining through milling is one of the wide-used cutting processes in woodworking and furniture industry. It is also one of the noisiest, due to the high noise immission levels that often exceed the accepted sanitary standards.

In this work the influence of the feed rate, the speed of the working shaft (or cutting speed) and the thickness of the out cut layer on the noise levels, measured at work place, generated during Pinus silvestris L. milling process has been evaluated.

Summary

Strengthening the links between education systems, in order to develop the potential of young people is at the core of European cooperation process. Leading institutions are there to introduce and provide better teaching and learning through use of new information and communication technologies (ICT). One of the priority areas of the Strategic framework for education and training („ET 2020“) is to promote and develop creativity and innovation through new instruments, which use modern ICT and by training teachers to use ICT.

Information and communication technologies provide a variety of methods and tools that open up new opportunities in distance learning students from the University of Forestry. They allow supporting the educational process by organizing it in a way, that takes into account the individual needs of students and allow building up of important digital competencies needed to achieve "knowledge-based" economy.

Summary

The paper presents a new approach for the 3D colour visualization of the obtained with the help of own mathematical model calculated results about the non-stationary temperature distribution in the volume of frozen wood materials with prismatic shape during their defrosting. An example for the application of the approach for visualization of the temperature distribution in frozen beech prisms with thickness 0,4 m, width 0,4 m, length 0,8 m, initial temperature -40 оC, and moisture content 0,3 kg.kg-1 (wood with ice from the bounded water in it) and 0,6 kg.kg-1 (wood with ice from both the bounded and the free water in it) during their defrosting at temperature of the processing medium 80 оC has been given. The results from the studies can be used for the creation of an optimal energy saved thermal treatment of prismatic wood materials during their defrosting with an aim of following plasticizing in the veneer production.

Summary

This paper presents the structure and functions of system for automatic control of the rotation frequency of an alternating current powerful electromotor of the cutting mechanism of machine for slice veneer production. In the system a microprocessor programmable frequency regulator for the supplying of the controlled electromotor have been inbuilt.

There is already the automated system integrated, as a result of which the productivity of the veneer slice machine has improved significantly, the specific energy consumption has reduced and the intellectual pressure of the operator has decreased.

Summary

The European Union (EU) policy, concerning employment and social activities, recognizes competitiveness and sustainability as essential goals for the EU to be achieved through building an economically dynamic labour market. To achieve these objectives, the EU should modernise working life, creating ‘more and better jobs’ as specified in the Lisbon Strategy, and deliver ‘smart, sustainable and inclusive growth’ according to the words of the Europe 2020 strategy. Ensuring quality of work and employment and healthy and safe working conditions are core elements in achieving these objectives.

A research on the dynamics of working conditions in EU member states has been carried out in the present article on the basis of the results from the fifth European Working Conditions Survey.

Summary

A methodology for the creation of colourful 2D diagrams using MS Excel 2010, illustrating the temperature distributions in the longitudinal sections of frozen logs during different moments of their defrosting, has been suggested in this paper. For the creation of the diagrams numerical results have been used, which represent the solutions to a non-linear mathematical model of the logs’ defrosting process. These numerical results are presented in files in the .txt format before their processing with the software of MS Excel 2010 aiming at the creation of the 2D colourful diagrams.

Summary

In the first and at the beginning of the second part of this work the methodology for creation of 2D colourful diagrams has been described as thematically-oriented sequence of the used procedures of MS Excel 2010. In this part of the work the methodology has been applied for the preparation of 2D colourful diagrams of temperature distribution in the longitudinal sections of a frozen oak log during its defrosting. The methodology can be used for the preparation of various 2D diagrams for the change of temperature, moisture, and other fields in the volume of different materials in the cases when the diagrams are created using extensive numerical results from models, adequately describing the studied processes.