A model is proposed to describe the local connection between the capacitive and the inductive unbalance functions of two neighbouring twisted pairs. A realistic simulation of the unbalance functions indicates that the constant ratio of the inductive unbalance with respect to the capacitive unbalance is a workable model. Using this model, it is demonstrated that the calculation of the reflective coupling constant for the calculation of reflective crosstalk is possible when one has disposal of the widely used coupling constants to predict Near-End and Far-End crosstalk in case the line ends are perfectly terminated. The reflective coupling constant is necessary to model the power spectral densities of the crosstalk signals when the line ends are not matched.

In this paper we present the results of electromagnetic field measurements near two RF transmitters: one in the medium wave domain and one in FM radio and television frequency range. The RF transmitters are situated at about 15 km distance from the town, but near them there are: tourist places; main roads; houses, where the public may be present. Using both a set of near field E & H probes and the adjustable dipole antennas, comparative measurements were made. Beside the instantaneous values of the fields, the maximum and average values for 1 minute observation period were determined.

This paper deals with the problem of measuring the thermal resistance of silicon p-n diodes. The values of this parameter given in the catalogues rarely correspond to the real conditions of device cooling, e.g. the diode operating on the heat-sink. Therefore, the value of the thermal resistance has to be obtained from measurements. In the paper a new comfortable method of the measurement of the thermal resistance of silicon p-n diodes, based on measurements of their d.c. current-voltage characteristic and the estimation of the model parameter values with the use of PARTS-software, is presented. The results of measurements obtained by the new method are compared to the standard pulse method.

Diffusion coefficient is an important quantity that affects any migration process on food or nutritional systems. Special care has to be done to migration of undesirable substances from packaging into foods, if the diffusion is the only process involved in mass transfer. The Fick´s equation resolution permits to describe the kinetic of migration from polymer packaging into food or simulant, once it was given the correct contour and initial conditions. Another important quantity is the partition coefficient, which quantifies the relation between the final or equilibrium concentrations in polymer and that in the food or simulant. Here it is proposed a simple procedure, based on numerical resolution of the Fick´s equation, where the diffusion coefficient could indirectly be measured, if the kinetic of migration had been measured and the partition coefficient is known.

Reliable, traceable and comparable measurements provide the rational basis for evaluation of the quality of a result and the starting point for laboratory accreditation. Nowadays good measurements are essential not only for manufacturing, science and trade, they also underpin a wide range of aspects of the quality of live, from healthcare to sport. Starting from the role of the National Institute of Metrology (INM) in assuring the traceability of all measurements, regardless their end-use and level of accuracy, the paper depicts some aspects related to the present state-of-art in the field of metrology in chemistry in Romania. The paper reviews locally available reference materials (RMs) and certified reference materials (CRMs) in quality of life related measurements, the experience of the INM in developing new measurement standards and aspects of certification of RMs issued in Romania. Practical examples on the use of CRMs for calibration, traceability and measurement uncertainty evaluation are discussed.