A numerical model for simulating Residence Time Distribution (RTD) of turbulent flows in helical static mixers is proposed and developed to improve the understanding of static mixers. The results of this model is presented in terms of different volumetric flow rate to illustrate the complicated flow patterns that drive the mixing process i...

this paper may be regarded as a new numerical method for the analysis of triangular thin plates using the natural area coordinates. previous studies on the solution of triangular plates with different boundary conditions are mostly based on the rayleigh-ritz principle which is performed in the cartesian coordinates. consequently, manipulation of the geometry and numerical calculation of the int...

objective:more similarity to in vivo medium may help to increase the proliferation and differentiation of cells at in vitro condition. the present study has investigated the effect of a dynamic mediumand nano hydroxyapatite (nha) presence on proliferation and differentiation of mesenchymal stem cells (mscs) to bone cells using electrospun polycaprolactone (pcl) scaffolds. methods: we prepared p...

springs are the  mechanical parts which have many application in industries. static and dynamic forces cause relaxation in these parts so that they lose some of their free length and reaction force. springs constant are very important in airplane and vailway industry since constant and variable forces are applied to them in period time, therefore it is necessary to avoid decreasing in spring co...

network expansion studies normally offer new power lines, new substations or expansion of existing substations. they are generally proposed based on technical requirements, but financial restrictions are not considered. because of financial restrictions, ranking of network expansion plans is required. in this paper an algorithm for such ranking, based on technical and financial view points and ...

background: the incomplete maturation of brain in preterm children results in long-term neurodevelopmental impairment. this study aimed to investigate the static balance function in children with a history of preterm birth. methods: participants were 31 preterm children including 21 moderately preterm (mpt), 10 very preterm (vpt), and 20 term children aged 5.5 and 6.5 years. the cervical vestib...

this study compares and contrasts tense and inherent aspect in english and persian lan-guage from a semantic and syntactic point of view. the aspectual verb system in both english and persian are semantically interpreted alike. however, in persian a group of stative verbs are grammaticalized by the imperfective obligatory morpheme mi-, while in english all sta-tive verbs perfective. furthermore...

physical and mechanical properties of alfalfa (medicago sativa, l.) grind are required for optimum design of equipment used in transporting, processing and storage of the material. this study was conducted to determine the effect of particle size (2.38, 3.36 and 4.76 mm) and moisture content (8, 9.3 and 11% wb) on some physical and mechanical properties of alfalfa grind. these properties includ...

the paper presents a mathematical base modeling combined to modified-winding -function-approach (mwfa) for eccentricity fault detection of a round-rotor synchronous machine. for this aim, a 6-pole machine is considered, and the machine inductances are computed by mwfa in healthy and also under eccentricity fault. a numerical discrete-time method has been proposed to machine modeling in voltage-...