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An on-site comparison of the quantum Hall effect (QHE) resistance standards of the Czech Metrology Institute (CMI) and of the Bureau International des Poids et Mesures (BIPM) was made in April 2017. Measurements of a 100 Ω standard in terms of the conventional value of the von Klitzing constant, R K-90, agreed to 6 parts in 1010 with a relative combined standard uncertainty u c = 25 × 10−10. Measurements of 10000 Ω/100 Ω and 100 Ω/1 Ω ratios agreed to 11 parts in 1010 with u c = 22 × 10−10 and to 33 parts in 1010 with u c = 32 × 10−10, respectively. The influence of the current reversal time has been systematically investigated in order to take into account possible errors due to the Peltier effect, which may be particularly large in 1 Ω standards. Main text To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCEM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

We analyse the application of an ultra wideband (UWB) balanced antipodal Vivaldi antenna to hyperthermia head and neck cancer treatment in this paper. Balanced antipodal Vivaldi antenna was primary developed for microwave imaging. The shape of isosurface, where specific absorption rate (SAR) decreases to 25% of its maximal value of one antenna, is observed in simple rectangular phantom at frequency 915 MHz for three different distances between antenna and phantom. Two different antenna configurations are then considered. Eight antenna configuration, where eight antennas are equidistantly placed in circle in one plane and three antenna configuration, where only three nearest antennas to the tumour region are placed in smaller circle with centre in the tumour region. Optimization of SAR distribution and thermal simulation was performed after electromagnetic simulation. Although thyroid gland tissue was covered by SAR quite well, its temperature did not rise. It confirms the importance of thermal simulation in treatment planning procedure.

Paper deals with a description of research activities in the field of Microwave Medical Diagnostics and Treatment done at the Dept. of EM Field, Czech Technical University (CTU) in Prague. History of these activities goes to year 1981, when the first apparatus for microwave hyperthermia cancer treatment has been developed at CTU and one year later started to be used for oncological patient treatments at Institute of Radiation Oncology (Hospital Bulovka in Prague).In present time we have several areas of research activities dealing with applications of microwave theory, technique and technologies in medical diagnostics and therapy.Future trends in medical applications of microwave technique and technology can be seen in development of new diagnostic and imaging methods based on microwaves. A significant importance for the future can be identified for the following microwave methods: Tomography, Radiometry, Measurement of complex permittivity, Imaging in the Terahertz waves band and Diagnostic radars.