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The aim of this work was the classification of milk samples with the use of Support Vector Machine networks. An electronic tongue, based on a sensor array of miniaturized solid-state potentiometric electrodes, was used for measurements of milk originating from various dairies (i.e. various brands) and with different fat content. The sensors were mounted into the measurement flow-cell developed at Warsaw University of Technology. Their signals were input to the Support Vector Machine neural network without a pre-processing stage. The results of the classification of milk by trademark and by fat content proved the proposed system to be very efficient.

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Ellipsometry is used to measure the strain induced in the oxide film by the electric field during the anodic oxidation of tungsten. The strain is found to vary as the 5/3 power of the field.and to equal 1% at a field of 5.25 • 106 V/cm under galvanostatic oxidation at 200 ~A/cm 2. Open-circuit transient analysis is used to determine the dependence of the current density and the dielectric constant on the field in the oxide film. The current is found to be limited by an effective field proportional to the product of the field and the dielectric constant. The dielectric constant is found to vary linearly with field, decreasing by 45% between zero field and the oxidation field. The Clausius-Mossotti relation is used to relate the variation in the dielectric constant to the strain in the film, and the results of the open-circuit transient analysis are found to be in very good agreement with the ellipsometric measurements of strain. It is concluded that field-induced strain in the oxide film has a strong effect on its dielectric constant, and through it on the el~ective field which controls the anodic oxidation process.In a previous paper (1), we reported a field dependence of the dielectric constant during the anodic oxidation of tantalum, niobium, and tungsten, and used an effective-field model to relate it to the field dependence of the ionic current density. Ellipsometry was used to measure the strains induced in the oxide films by changes in field, and the associated changes in the low and high frequency dielectric constants were found to agree reasonably well with values predicted using the Clausius-Mossotti relation between dielectric constant and density. By assuming log (i) proportional to an effective field, we found that the field dependence of the dielectric constant could account fairly well for the curvature in the dependence of log (i) on E for the anodic oxidation of tantalum (2) and niobium (3). We were unable to test an effective field model for tungsten because no attempt had been made to measure log (i)-E curvature. We have now developed a technique for determining log (i)-E curvature from the analysis of open-circuit transients (4), and we apply this technique here to the anodic oxidation of tungsten.More recently, Young and co-workers found that the field induces anisotropy in the anodic oxides of tantalum (5) and niobium (6), and carried out an anisotropic analysis of their optical data. Their values for the sign and magnitude of the strains and index changes agreed reasonably well with the results of our earlier work which used isotropic optical analysis. They varied the field over a wider range than we had used and found a quadratic field dependence instead of the linear dependence we had reported. More recent work in our laboratory (7) confirms the optical anisotropy of the anodic oxide of niobium, but not the quadratic field dependence, and concludes that relaxation processes complicate attempts to determine the field dependence. Studies on tantalum film capacitors (8, 9) found a complicated...