Modern ac-dc transfer equipments can operate up to 1 GHz at least. These equipments and the related ac-voltage measurements may be attractive for calibrating high frequency power sensors in term of ac-dc transfer difference instead of effective efficiency. Furthermore, below 30 MHz, the ac-voltage standard can be also used as powerful alternative and complement to the microcalorimeter technique for the realization of the RF power standard. In the paper experimental measurements and data analysis are presented that prove the previous assertions.

Design of experiments is a theory that can not be neglected in any technical education as well as in applied statistics or economics education. For longer than a year lasted a project aiming to publish a new book in Slovak language entitled Design of Experiments with SAS. This book of eleven Chapters combines theoretical knowledge in the scientific area of design and evaluation of experimental results with application of SAS® statistical software.
A model of a simple strategy for design of experiments starts with description of a problem, choosing an appropriate design with responses and factors, collection of experimental data which is followed by fitting of an appropriate model that can be used for predicting.

This paper present a new instrument named STASI (Seismic and Accelerometers Calibration System) invented and patented by Aldo Renato Terrusi of ENEA - Italian Agency for New Technologies, Energy and Environment (patent n° RM2004A000147,3-22-2004). This paper is a brief overview on the state of the art at international level, describing and comparing the general characteristics and costs of the instruments in relation with what is currently available on the world market. The modifications on the STASI prototype were made after the I.N.RI.M.'s comments and the experimental tests performed by ENEA Casaccia Metrology Laboratories (SIT Center n° 10), which showed an improvement to reliability, calibration's uncertainty of and the ease of use.

A laser interferometer mercury manobarometer has been designed and manufactured. It works from 1 kPa up to 130 kPa (gauge, absolute and differential modes) with line pressure up to 500 kPa. The uncertainty budget depends on the range and working mode. In absolute mode the expanded uncertainty ranges from 0.13 Pa up to 0.42 Pa.

A loading frame structure and a piezoelectric actuator were applied to a force comparator referring to a tuning-fork-type force transducer. The gravitational force acting on the loading frame was shared between the reference transducer and another transducer under calibration. Introduction of the loading frame structure improved reproducibility of the force transducer under calibration, and the piezoelectric actuator improved force controllability in comparison with that of the previous reported force comparator. Because of the excellent linearity and small hysteresis of the reference transducer, the force comparator showed a capability comparable to dead-weight-type force standard machines.