Now showing 1 - 4 of 4
  • Publication
    LASER TECHNOLOGIES – MASTER’S PROGRAM BETWEEN TWO EUROPEAN UNIVERSITIES OF APPLIED SCIENCES FROM LATVIA AND GERMANY
    (2017)
    Aivars Vilkaste
    ;
    ;
    Hristina Deneva
    ;
    ; ;
    Pāvels Narica
    Laser equipment and laser technologies are among the most modern, fastest growing and most promising branches of science and technology in the 21st century. The first laser was created in 1960 and for about 55 years, today there is hardly any area of our lives in which lasers and related technologies are not applied. Laser systems and related innovative technologies ensuring high precision, productivity and quality of production have been developed and proposed worldwide from hundreds of scientific research institutes and companies. The Master's program is accredited in two European universities in Germany and Latvia and allows for the production of double diplomas. The course is based on international experience and reflects the most recent advances in laser techniques and technologies. The program examines the physical fundamentals and technical realization of various types of laser systems and their specific characteristics. First the necessary foundations of the laser physics, optics and the interaction of radiation with matter are presented, followed by more detailed examination of the problems of laser technology in various fields of science, technology and industrial production. Basic physical and technical solutions of the building blocks of lasers are presented in details, such as: optical resonators, active environments, excitation systems, management systems, laser generation. As well as specific issues and practical examples of industrial applications are described.
  • Publication
    STUDY OF AUXILIARY GAS PRESSURE ON LASER CUTTING TECHNOLOGY
    (2017) ;
    Hristina Deneva
    ;
    Two types of electrical sheet steel M250-35A and M530-50A were used to cut by melting with a TruLaser 1030 technological system. It was observed that pressure of auxiliary gas had a major effect on kerf width b and cut angle deviation α. Nitrogen as an assisted gas has been taken. The basic parameters as laser power, cutting speed, focus position were constantly supported and the pressure was changed from 4 bar to 20 bar by step 2 bar. As well as the experimental results of gas pressure on entrance and exit kerf widths, have been analyzed and discussed in this study.
    Scopus© Citations 3
  • Publication
    INFLUENCE OF DEFOCUS POSITION ON LASER CUTTING PROCESS IN SHEET STEEL
    (2017) ;
    Hristina Deneva
    ;
    Some researches about influence of defocus position to carry out laser cutting technological process through melting when producing lamellae for electric motors are presented here. Experimental series at defocus position Δf in the range – 3, 5 mm to + 3, 5 mm with two grade electrical steels M250-35A and M530-50A are described, too. The experiments are performed with a technological laser system TruLaser 1030. Functional dependencies of cutting width from defocus position b = b (Δf) have been shown. Theoretical relationships connected to the change of impact on a unit of area working spot over power density qs of the laser radiation and interaction time tproz (respectively cutting speed v), are examined too
    Scopus© Citations 4
  • Publication
    LASER AS A DEVICE FOR MEASUREMENT OF THIN THREADS - A SCHOOL LABORATORY EXPERIMENT IN PHYSICS
    (2017)
    Hristina Deneva
    ;
    ;
    The physics of the last century is included in all EU curricula and emphasis in education is shifted from content to the forms, methods and means of teaching and learning. Different kinds of lessons (including laboratory classes) and their didactic structure are subject to the understanding, adoption and creating conditions to build motivation to learn physics and astronomy, active utilization of physical knowledge and building cognitive and practical skills. Performance of demonstration and laboratory classes using a laser device is a type of teaching strategy to good education in physics. Properties of laser light as observation, classification, communication, drawing conclusions, planning, interpretation and forecasting, are particularly suitable when monitoring and studying the phenomena of interference and diffraction. Through both qualitative and quantitate ways, in this paper is presented a physical experiment for measurement of thin threads in a High school from students. Experimental skills will enhance interest in physics and especially to modern applications of laser devices, as well as career guidance of students.