In this paper methods and their examination results for automatic segmentation and parameterization of vessels based on spectral domain optical coherence tomography (SD-OCT) of the retina are presented. We present three strategies for morphologic image processing of a fundus image reconstructed from OCT scans. A specificity of initial image processing for fundus reconstruction is analysed. Then, the parameterization step is performed based on the vessels segmented with the proposed algorithm. The influence of various methods on the vessel segmentation and fully automatic vessel measurement is analysed. Experiments were carried out with a set of 3D OCT scans obtained from 24 eyes (12 healthy volunteers) with the use of an Avanti RTvue OCT device. The results of automatic vessel segmentation were numerically compared with those prepared manually by the medical doctor experts.

This study presents the dependence of the level and harmonic structure of the cogging torque in permanent magnet synchronous motors (PMSM) to imperfections of permanent magnet (PM) dimensions and positions, which can not be avoided in massproduction. Slightly diverse dimensions and misplacements of PMs are introducing asymmetries in magnetic field distribution which cause additional harmonic components. A finite element method (FEM) and Fast Fourier transform (FFT) were used to calculate cogging torque harmonic components with regard to several combinations of PM assembly imperfections. It has been established and proved that unequal PMs cause magnetic asymmetries which give rise to additional cogging torque harmonic components and consequently increase the total cogging torque. It is also shown that in some particular combinations the influence of an individual PM imprecision could compensate with others due to different phase shifts which can result even in the decrease of cogging torque. Considering presented results it is possible to foresee which additional harmonic components will comprise the cogging torque of mass-produced PMSMs due to PM imperfections. In this way the designers are able to predetermine required manufacturing tolerances to keep the level of cogging torque in a admissible level. Simulation results were verified and confirmed by laboratory tests.

Grounding electrode resistance non-linearly changes under impulse conditions due to soil ionisation phenomenon. Several models have been proposed to model soil ionisation for grounding electrodes applications. However, to date, there is yet an attempt made to compile all these works into a comprehensive review article. Therefore, this paper is written with the objective of summarizing all related works in this field as a one– stop reference. With reference to the literature, this paper is written to summarize the working principles of the soil ionisation models as well as the accuracy and performance analysis of the models. This paper, particularly highlights the deficiencies of the available models in terms of accuracy and performance. This knowledge will contribute to the development of a new accurate and efficient soil ionisation model.