Characterization of the Graphite Pile as a Source of Thermal Neutrons

The absorption cross sections of low energy neutrons obey 1/v law for most materials. Therefore, the detection efficiency of a particular detector increase with decreasing neutron energy. Consequently, most of neutron measuring instruments consist of the detector of thermal neutrons which is located inside of the polyethylene moderator. Development of such instruments requires testing and response calibrations in the field of thermal neutrons. Availability of thermal neutron beams on nuclear reactors is limited and access to them is rather complicated, so it is more convenient to moderate neutrons from the radionuclide neutron sources. Since radionuclide neutron sources are producing fast neutrons it is necessary to use an appropriate moderator material like heavy water or graphite to thermalize neutrons from the source and to avoid thermal neutron capture in the same time.The absorption cross sections of low energy neutrons obey 1/v law for most materials. Therefore, the detection efficiency of a particular detector increase with decreasing neutron energy. Consequently, most of neutron measuring instruments consist of the detector of thermal neutrons which is located inside of the polyethylene moderator. Development of such instruments requires testing and response calibrations in the field of thermal neutrons. Availability of thermal neutron beams on nuclear reactors is limited and access to them is rather complicated, so it is more convenient to moderate neutrons from the radionuclide neutron sources. Since radionuclide neutron sources are producing fast neutrons it is necessary to use an appropriate moderator material like heavy water or graphite to thermalize neutrons from the source and to avoid thermal neutron capture in the same time

Mutual combination of selected principles and technologies of Industry 4.0 and quality management methods - case study

In this paper the case study of the application of Failure Mode and Effects Analysis (FMEA) on the testbed “Smart Factory Line” has been described. The main goals of this study have been to verify feasibility and applicability of FMEA on such complex technical system and to show real possibilities of integration of Industry 4.0 principles and technologies with selected methods of quality management. The significant part of the paper is formed by extensive literature review of the related topics such as mass customization and individualization, Industry 4.0, Quality 4.0, fault management and their selected principles, methods and technologies, putting the stress on the team cooperation of experts of different specializations. The attention also has been put on the describing testbeds as platforms for the academy world and practice connection. This case of the practical integration of the smart factory testbed design and its products with the new FMEA approach based on the harmonized AIAG and VDA manual has brought new views on the practical realization of smart factories, on importance of building Quality 4.0 and on requirements for interdisciplinary education of the technicians and quality specialists for Industry 4.0.</p

In-orbit commissioning of Czech nanosatellite VZLUSAT-1 for the QB50 mission with a demonstrator of a miniaturised lobster-eye X-ray telescope and radiation shielding composite materials

This paper presents the results of in-orbit commissioning of the first Czech technological CubeSat satellite of VZLUSAT-1. The 2U nanosatellite was designed and built during the 2013 to 2016 period. It was successfully launched into Low Earth Orbit of 505km altitude on June 23, 2017 as part of international mission QB50 onboard a PSLV C38 launch vehicle. The satellite was developed in the Czech Republic by the Czech Aerospace Research Centre, in cooperation with Czech industrial partners and universities. The nanosatellite has three main payloads. The housing is made of a composite material which serves as a structural and radiation shielding material. Anovel miniaturized X-Ray telescope with lobster-eye optics and an embedded Timepix detector represents the CubeSat's scientific payload. The telescope has a wide field of view. VZLUSAT-1 also carries the FIPEX scientific instrument as part of the QB50 mission for measuring the molecular and atomic oxygen concentration in the upper atmosphere