Transmission line structure based on substrate integrated waveguide (SIW) loaded with new structure of octagonal complementary split ring resonator (CSRR) has been proposed. The SIW loaded CSRR pair is used in dual/quad octagonal structure to design dual band pass filter (single and double pole) with improved performance characteristics. The proposed band pass filter (BPF) yields two passbands ...

The Galerkin weighted residuals method is extended solve the laminar, fully developed flow and heat transfer of Al2O3-water nanofluid inside polygonal ducts with round corners for the constant heat flux and uniform wall temperature boundary conditions. Using the method, semi-analytical, closed-form solutions are obtained for the friction coefficient and the Nusselt number in terms of the radius...

OBJECTIVE The purpose of this systematic review was to evaluate the effectiveness of roll-over protection structures (ROPS) as an engineering control for prevention of fatalities from farm tractor roll-overs. METHODS Using a systematic approach to literature searching, relevant studies from peer-reviewed journals, technical and government reports, and unpublished reports were retrieved. Studi...

Hydrogen sulfide (H2S) gas levels were monitored in the human-occupied zone at four spent mushroom compost (SMC) storage sites during removal of SMC for application on agricultural land. During SMC removal operations, H2S gas monitors were mounted on the outside of the tractor positioned at the SMC periphery, and worn by individual tractor drivers. The highest H2S concentrations (10 s average) ...

The aim of this paper and its sequel is to introduce and classify the holonomy algebras of the projective Tractor connection. After a brief historical background, this paper presents and analyses the projective Cartan and Tractor connections, the various structures they can preserve, and their geometric interpretations. Preserved subbundles of the Tractor bundle generate foliations with Ricci-f...

In this paper a geometric approach is suggested to ®nd the closest approximation to Euclidean metric based on geometric measures of the digital circles in 2D and the digital spheres in 3D for the generalized octagonal distances. First we show that the vertices of the digital circles (spheres) for octagonal distances can be suitably approximated as a function of the number of neighborhood types ...

In order to investigate the eff ect of transition of mounted implements from operation to transport on longitudinal stability of a tractor that works on sloping land, a mathematical model was developed. In this model two operation modes for a mounted chisel plow were considered: penetration of the plow into the soil and depth reduction of it, and the eff ects of transferred forces and torques f...