Search

Using the deep-level transient spectroscopy and reverse recovery method, the minority carrier lifetime in the base n0-layers of high-voltage GaAs p+–p0–i–n0–n+-diodes grown by the liquid phase epitaxy in argon atmosphere has been estimated before and after irradiation by neutrons with the energy of 1 MeV and the fluence of 1.6 × 1014cm–2. Correlation between the values of the minority carrier lifetime determined by both methods was found. EL2 defects where shown to govern the dynamic switching characteristics of non-irradiated GaAs diodes, while the switching process in the irradiated diodes is determined by the acceptor-like states of defect bands located above the midgap, which are D–states of a three-charged donor. Having been irradiated with neutrons, the diodes revealed a significant decrease in the time of their reverse recovery upon changing the character of the diode switching from the “hard” mode to the “soft” one.

The article considers the verification and validation processes algorithms of the finite element model calculation results of wooden structures joints with the use of glued steel flat rods. The introduction shows the relevance of the determination processes the accordance between numerical and mathematical models and numerical and physical models accepted for calculation. As an example, methods for calculating multicomponent joints of wooden structures on glued steel flat rods pasted into wood are considered, and structural nodes solutions of wooden trusses on these type connections are given. The second paragraph describes the features of finite element models creation for calculating the stress-strain state of the glued joint of flat rods with wood when they are pulled out with rigid nodes in the conjugation zone of finite elements from various materials and when contact surfaces are created in this zone. A mathematical solution of this problem, reduced to the plane deformation problem for finite canonical domains, is considered. An analytic solution of this three-dimensional problem, reduced to the plane deformation problem for finite canonical domains, is considered. The mathematical solution is based on obtaining functions that are biorthogonal to the Papkovich-Fadl eigenfunctions. The calculation results comparison of the stress-strain state of the finite element model of the steel flat rods' glued joint with wood, the analytical solution and experiment are given. On the basis of verification and validation it was shown that the proposed approaches to the construction and calculation of the glued joint of steel flat rods with wood can be reasonably applied to determine the stress-strain state and the design of the wooden structures nodes