Narrow Results

The improved safety margins in complex systems have attained prime importance in the modern scientific environment. The analysis and implementation of complex systems demands the well quantified accuracy and capability of measurements. Careful measurement with properly identified and quantified uncertainties could lead to the actual discovery which further may contribute for social developments. Unfortunately most scientists and students are passively taught to ignore the possibility of definition problems in the field of measurement and are often source of great arguments. Identifying this issue, ISO has initiated the standardisation of methodologies but its Guide to the Expression of Uncertainty in Measurement (GUM) has yet to be adapted seriously in tertiary education institutions for understanding the concept of uncertainty. The paper has been focused for understanding the concepts of measurement and uncertainty. Further a case study for calculation and quantification of UOM for high voltage electrical testing of ceramic insulators has been explained.

The present paper discusses the establishment of traceability of reference grade hydrometers at National Physical Laboratory, India (NPLI). The reference grade hydrometers are calibrated and traceable to the primary solid density standard. The calibration has been done according to standard procedure based on Cuckow's Method and the reference grade hydrometers calibrated covers a wide range. The uncertainty of the reference grade hydrometers has been computed and corrections are also calculated for the scale readings, at which observations are taken.

Over the last period, increasing attention has been paid to measurement of small forces which play a more important role in nanotechnology and other significant areas such as MEMS (Micro-Electro-Mechanical Systems) and NEMS (nano-electro-mechanical systems) which can be found into everyday products (mobile phones, MP3 players, PCs, cars). In this respect, the development of mass standards and measurement techniques below the current limit of 1 milligram is vital to provide traceability to the SI for such measurements. In Romania, the Mass laboratory of INM considered it necessary to extend the dissemination of the mass unit below 1 mg, in order to meet current needs. Using the subdivision method and starting from the national prototype kilogram No. 2, all necessary experiments were performed for the first time in Romania to extend mass unit traceability till 100 μg. This extension also supports the provision of mass calibrations for low force measurements. The associated measurement procedure and measurement uncertainty results obtained in the calibration are described. In the article are also presented some of the worldwide methods currently used for measuring small forces.