Proposal for improving of paddy rice drying process in dryers inclined pools

The operation of inclined type dryers for paddy rice is studied to improve their operation and efficiency, considering the variables of drying time, humidity distribution in the rice layer after drying and air velocities within the plenum. Simulating the distribution and velocities of the air flow before crossing the rice layer, the outlet ducts to the plenum are relocated and dampers are placed to distribute the flow evenly. On the other hand, it is proposed to replace the flat-type mesh with a zigzag-type mesh. To verify the proposed modifications, a scale model was built to determine the humidity and drying time variation inside the rice layer, obtaining more uniform moisture percentages within the rice layer and a decrease in drying time.

A Note on the Three Dimensional Dirac Operator with Zigzag Type Boundary Conditions

In this note the three dimensional Dirac operator $$A_m$$ A m with boundary conditions, which are the analogue of the two dimensional zigzag boundary conditions, is investigated. It is shown that $$A_m$$ A m is self-adjoint in $$L^2(\Omega ;{\mathbb {C}}^4)$$ L 2 ( Ω ; C 4 ) for any open set $$\Omega \subset {\mathbb {R}}^3$$ Ω ⊂ R 3 and its spectrum is described explicitly in terms of the spectrum of the Dirichlet Laplacian in $$\Omega $$ Ω . In particular, whenever the spectrum of the Dirichlet Laplacian is purely discrete, then also the spectrum of $$A_m$$ A m consists of discrete eigenvalues that accumulate at $$\pm \infty $$ ± ∞ and one additional eigenvalue of infinite multiplicity.

EXPERIMENTAL STUDIES ON THE INFLUENCE OF TRANSVERSE REINFORCEMENT FOR STRENGTH OF COMPRESSED REINFORCED CONCRETE ELEMENTS

The infl uence of transverse reinforcement, including indirect reinforcement, on the strength of compressed reinforced concrete elements is analyzed. This question arose in connection with the possibility of increasing the strength of short reinforced concrete elements loaded with a longitudinal force with small eccentricities within the section of the element. For such elements, the cage eff ect may appear, associated with the coeffi cient of transverse deformations, the magnitude of which is a direct factor in the destruction of the concrete sample, and the limitation of these directly aff ects the bearing capacity of the sample in the direction of increase. The infl uence of transverse reinforcement in the form of stirrups located with diff erent spacing, as well as indirect reinforcement in the form of meshes with a classical rectangular cell and meshes of the “zigzag” type is considered.

Наноструктуры AlN и GaN: аналитические оценки характеристик электронного спектра

For AlN and GaN infinite flat sheets, free and decorated nanoribbons with the zigzag-type edges and linear chains the analytical expressions for the band-gap widths, characteristic velocities and effective masses are obtained. Numerical results are compared with the values of the corresponding characteristics calculated within the same models for the silicon carbide and carbon nanostructures. The role of substrate is also briefly discussed.