Abstract. The isothermal and non-isothermal characteristics of silicon carbide Schottky diodes in the wide range of currents and ambient temperatures are investigated in this paper. The measurements of the diodes characteristics have been performed with the use of a pulse method, with fast registration of measurement points after the diode current turning on, or with the use of a fully static method, in which the self-heating phenomenon is taken into account. Apart from the measurements, the series of numerical experiments, giving the isothermal and non-isothermal characteristics as a result, were executed. The complex, accurate numerical procedures as well as simplified analytical calculations were implemented. A good conformity of all calculation and measurement results have been obtained.In the presented investigations, for relatively high currents and ambient temperatures, the influence of self-heating on the SiC Schottky diodes static characteristics is significant. The large (even 4 V for the ambient temperature 300• C ) values of voltages corresponding to the nominal diode currents have been observed.

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Unmanned aerial vehicles (UAVs) have been used extensively for search and rescue operations, surveillance, disaster monitoring, attacking terrorists, etc. due to their growing advantages of low-cost, high maneuverability, and easy deployability. This study proposes a mixed-integer programming model under a multi-objective optimization framework to design trajectories that enable a set of UAVs to execute surveillance tasks. The first objective maximizes the cumulative probability of target detection to aim for mission planning success. The second objective ensures minimization of cumulative path length to provide a higher resource utilization goal. A two-step variable neighborhood search (VNS) algorithm is offered, which addresses the combinatorial optimization issue for determining the near-optimal sequence for cell visiting to reach the target. Numerical experiments and simulation results are evaluated in numerous benchmark instances. Results demonstrate that the proposed approach can favorably support practical deployability purposes.

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