Advances in Intelligent Systems and Computing

Introduction: Every measuring instrument is subject to ageing as a result of mechanical, chemical or thermal stress and thus delivers measured values that change over time. This cannot be prevented, but it can be detected in good time by calibration. The Egyptians already knew this almost 5000 years ago. The workers calibrated their yard sticks by comparing them with a “royal cubit” (approx. 52.36 cm) made of stone and thus managed to achieve, for example, side lengths on the Cheops pyramid of 230.33 m which differ from each other by only about 0.05 per cent. In the process of calibration, the displayed value of the measuring instrument is compared with the measuring result of a different measuring device which is known to function correctly and accurately and which itself has been made to coincide directly or indirectly with a national (or international) reference instrument (standard) (Fig. 1). One talks about verification  when the calibration has been carried out or supervised by an official body. Both of these variants are purely intended for determining the quality of the displayed values. No intervention to the measuring instrument itself is allowed. With adjustment, it is understood that there is an intervention to the measuring device in order to minimise a detected measuring deviation. Typically, adjustment is followed by a further calibration, in order to check and document the final state of the measuring instrument following the intervention. In contrast to verification, which will lose its validity after a period of time set by law, the validity period of a calibration is subject to practical specifications0.

Abstract: This review is devoted to the features of the formation and application of ceramic membranes in water treatment technologies. The structure, composition and geometric configuration of ceramic membranes were analyzed. A comparison with polymer membranes was made, as a result of which it was determined that the use of ceramic membranes is safer for the environment and will contribute to the creation of sustainable water treatment technologies, which can be completely closed. Despite their widely recognized shortcomings – fragility and cost, the use of ceramic membranes can pay off quickly due to higher performance and longer service life. Besides, a promising direction in overcoming these shortcomings is the fabrication of cheap and highly functional ceramic membranes using nanotechnology, modification of their surface against biofouling and for disinfection and creation of hybrid membranes. Additionally, the perspective direction of ceramic membranes creation based on low-cost raw materials and the development of cheap anisotropic inorganic membranes is outlined. In general, it is noted that membrane technologies, while eliminating certain shortcomings, will be recognized as a universal and "green" method of wastewater treatment, which will address a wide range of water treatment issues