• SOCIETY & ”INDUSTRY 4.0”

    CHARACTERISTICS OF RADIATION AND SOURCES OF RADIATION AS A RESULT OF HUMAN ACTIVITY

    Industry 4.0, Vol. 2 (2017), Issue 6, pg(s) 312-316

    The main features of the radiation environment in the surrounding environment are presented. Over the last 5 years no values other than the natural ones have been observed, with the lowest values in Veliko Tarnovo. The main characteristics of the radiation in operation in nuclear power plants and the major accidents resulting from the operation of the NPP in the development of humanity are shown. Radiation as a result of the uranium mining and uranium processing industry in Bulgaria is also under consideration. It also shows the actions of radiation as a result of other people’s activities.

  • SCIENCE

    SOURCE SKIN DISTANCE DEPENDENCE OF RESPONSE OF IN VIVO EXIT DOSE DIODE DETECTORS USED IN

    Science. Business. Society., Vol. 2 (2017), Issue 2, pg(s) 46-50

    Linear Accelerators and Cobalt units are common source of radiation for external radiotherapy. In Vivo Dosimetry (IVD) is a real time quality control set of methods used in cancer treatment clinics to assure that dose is delivered as prescribed to tumor, while surrounding healthy tissue is spared. Silicon Diode detectors are among most popular detectors used for IVD. In certain clinical conditions, both entrance and exit dose measurements are needed, for quality insurance, to calculate the dose received by tissue or organ inside patient’s body. Response of silicon diode detectors depends on multiple factors therefore prior of use in IVD each detector needs to be calibrated and corresponding factors of correction need to be calculated. Correction factors are needed to calculate dose for different field sizes, angle between beam axis and couch axis, skin to source distance (SSD), temperature etc. In this work we present our calculation of exit dose calibration factors for six silicon diode detectors made by PTW Frieburg Germany. Diodes are calibrated for exit dose under either 6 MVor 18 MV beam of photons as designated by manufacturer. Further we study dependence of response of individual diodes on distance from source and calculate corresponding correction factors. It was found that exit dose SSD dependence is pronounced and correction factors are necessary for exit dose IVD with diode detector in clinics.

  • INNOVATIVE SOLUTIONS

    DEVICE FOR FOG DENSITY CONTROL

    Innovations, Vol. 5 (2017), Issue 1, pg(s) 21-24

    А relatively inexpensive instrument (for fog density control), which works in the visible specter, is presented. Its purpose will be to alert the occurrence of fog or visible pollution in the air. It can also detect, if the cleaning fog has reached all areas. This equipment can be used to assess the density of fog. The device is designed for continuous monitoring of the atmospheric air and detection of dispersed agents in the form of aerosols. The total concentration of aerosols is measured and if it exceeds the pre-set threshold, an indication is given via a LED and the information can be exported to external systems. The principle of operation of the device is based on the spectrophotometric method. A beam of monochromatic light is passed through the investigated environment and its intensity is attenuated by the presence of pollutants. The hardware of the device is described, as well as its construction, software and the measuring procedure.

  • CFD MODELLING OF A COMPLETE ELECTRIC ARC FURNACE ENERGY SOURCES

    Innovations, Vol. 4 (2016), Issue 1, pg(s) 22-24

    This paper, concentrates on a three-dimensional (3D) computational fluid-dynamics (CFD) model for coal combustion and electrode radiation inside an electric-arc furnace (EAF). Simulation of the complete EAF model includes combustion reactions of coal particles and radiation from electrodes. Particle surface and gas phase reactions were used to predict injected coal particle combustion. The CFD model provided detail information for the coal particles combustion and radiation interactions phoneme inside the electric-arc furnace.

    Results showed that CFD simulation could efficiently be used to develop and investigate EAF in design phase.