The irregularity profiles of steel samples after vapour blasting were measured. A correlation analysis of profile parameters was then carried out. As the result, the following parameters were selected: Pq, Pt, PDq, Pp/Pt and Pku. Surface profiles after vapour blasting were modeled. The modeled surfaces were correctly matched to measured surfaces in 78% of all analyzed cases. The vapour blasting experiment was then carried out using an orthogonal selective research plan. The distance between the nozzle and sample d and the pressure of feed system p were input parameters; selected surface texture coefficients were output parameters. As the result of the experiment, regression equations connecting vapour blasting process parameters p and d with selected profile parameters were obtained. Finally, 2D profiles of steel samples were forecasted for various values of vapour blasting parameters. Proper matching accuracy of modeled to measured profiles was assured in 75% of analyzed cases.

The paper presents traditional analogue and digital techniques in partial discharge measurement. The discharge current pulses are measured from high voltage machines like power plant generators and transformers. The presented modern digital techniques are suitable for all measurements where impulse energy will be calculated.

Outdoor remote temperature measurements in the infrared range can be very inaccurate because of the influence of solar radiation reflected from a measured object. In case of strong directional reflection towards a measuring device, the error rate can easily reach hundreds per cent as the reflected signal adds to the thermal emission of an object. As a result, the measured temperature is much higher than the real one. Error rate depends mainly on the emissivity of an object and intensity of solar radiation. The position of the measuring device with reference to an object and the Sun is also important. The method of compensation of such undesirable influence of solar radiation will be presented. It is based on simultaneous measurements in two different spectral bands, shor-twavelength and long-wavelength ones. The temperature of an object is derived from long-wavelength data only, whereas the short-wavelength band, the corrective one, is used to estimate the solar radiation level. Both bands were selected to achieve proportional changes of the output signal due to solar radiation. Knowing the relation between emissivity and solar radiation levels in both spectral bands, it is possible to reduce the measurement error several times.

The tendencies of modern industry are to increase the quality of manufactured products, simultaneously decreasing production time and cost. The hybrid system combines advantages of the high accuracy of contact CMM and the high measurement speed of non-contact structured light optical techniques. The article describes elements of a developed system together with the steps of the measurement process of the hybrid system, with emphasis on segmentation algorithms. Additionally, accuracy determination of such a system realized with the help of a specially designed ball-plate measurement standard is presented.

A data logger has been built to record, for a month, the power consumption of various equipment and the temperature at different points inside and outside of a radio communication base station operated by Vodafone Portugal. Here we show how the concerns with measurement uncertainty led us to choose an analog system over a digital one for AC power measurement.

To gather reproducible measurement results, metrologists need a variety of competences. Yet, also other groups of staff in a manufacturing enterprise need competences in metrology in order to assure the appropriate specification of tolerances or sufficient consideration of inspectional requirements in production processes.

Therefore, the strict focus of metrological qualification on staff preparing or performing the actual measurements is insufficient for the efficient assurance of conformity. Additionally, on the one hand a demand-oriented qualification concept is needed to impart required fundamental knowledge on manufacturing metrology according to the specific needs of each user group. On the other hand, appropriate measures of knowledge management have to be applied in order to assure a proper application of the gathered knowledge and enhance mutual understanding for the requirements of other involved user groups.

Thus, as amendment for user-specific measures of formal qualification, a concept has been developed to enable knowledge transfer among different groups and departments in an enterprise. By this holistic approach, the impact of measures of qualification can be increased and high product quality can be achieved as a common aim of all related groups of staff.

When observations are autocorrelated, standard formulae for the estimators of variance, s2, and variance of the mean, s2 (x), are no longer adequate. They should be replaced by suitably defined estimators, s2a and s2a (x), which are unbiased given that the autocorrelation function is known. The formula for s2a was given by Bayley and Hammersley in 1946, this work provides its simple derivation. The quantity named effective number of observations neff is thoroughly discussed. It replaces the real number of observations n when describing the relationship between the variance and variance of the mean, and can be used to express s2a and s2a (x) in a simple manner. The dispersion of both estimators depends on another effective number called the effective degrees of freedom Veff. Most of the formulae discussed in this paper are scattered throughout the literature and not very well known, this work aims to promote their more widespread use. The presented algorithms represent a natural extension of the GUM formulation of type-A uncertainty for the case of autocorrelated observations.

A thermal resistance characterization of semiconductor quantum-well heterolasers in the AlGaInAs-AlGaAs system (λst ≈ 0.8 μm), GaSb-based laser diodes (λst ≈ 2 μm), and power GaN light-emitting diodes (visible spectral region) was performed. The characterization consists in investigations of transient electrical processes in the diode sources under heating by direct current. The time dependence of the heating temperature of the active region of a source ΔT(t), calculated from direct bias change, is analyzed using a thermal RTCT equivalent circuit (the Foster and Cauer models), where RT is the thermal resistance and CT is the heat capacity of the source elements and external heat sink. By the developed method, thermal resistances of internal elements of the heterolasers and light-emitting diodes are determined. The dominant contribution of a die attach layer to the internal thermal resistance of both heterolaser sources and light-emitting diodes is observed. Based on the performed thermal characterization, the dependence of the optical power efficiency on current for the laser diodes is determined.

In the paper a new method of Random Telegraph Signal (RTS) noise identification is presented. The method is based on a standardized histogram of instantaneous noise values and processing by Gram-Charlier series. To find a device generating RTS noise by the presented method one should count the number of significant coefficients of the Gram-Charlier series. This would allow to recognize the type of noise. There is always one (first) significant coefficient (c0) representing Gaussian noise. If additional coefficients cr (where r > 0) appear it means that RTS noise (two-level as well as multiple-level) is detected. The coefficient representing the Gaussian component always has the highest value of all. The application of this method will be presented on the example of four devices, each with different noise (pure Gaussian noise signal, noise signal with two-level RTS noise, noise signal with three-level RTS noise and noise signal with not precisely visible occurrence of RTS noise).

Additional motor vibrations are the result of a faulty bearing. They are reflected in the harmonic content of stator currents. The object of the investigation presented in the paper are measurements related to diagnostics of induction motors, especially damages caused to bearings. Due to the fact that the amplitude of the network voltage basic harmonic in the current spectrum is high in comparison with components responsible for damages of bearings, preliminary elimination of this component from the analog current signal has been proposed.

The problem with interpretation of diagnostic measurements in present systems is the difference between measurement results of characteristic frequencies and theoretical calculations.

In the proposed measurement system this problem was solved in such a way that the value of the angular speed and of the supply frequency is calculated on the basis of appropriate components in the very same current spectrum that is further used in the search for diagnostic components.

The paper presents also the measuring system and provides results of the investigations carried out on a motor encumbered with a specially prepared defect.

A model-based approach, the Model-View-Interactor Paradigm, for automatic generation of user interfaces in software frameworks for measurement systems is proposed. The Model-View-Interactor Paradigm is focused on the "interaction" typical in a software framework for measurement applications: the final user interacts with the automatic measurement system executing a suitable high-level script previously written by a test engineer. According to the main design goal of frameworks, the proposed approach allows the user interfaces to be separated easily from the application logic for enhancing the flexibility and reusability of the software. As a practical case study, this approach has been applied to the flexible software framework for magnetic measurements at the European Organization for Nuclear research (CERN). In particular, experimental results about the scenario of permeability measurements are reported.