natural convection heat transfer from a tube bundle in the indirect water bath heaters is investigated. a computer-code is used for the solution of the governing equations of mass, momentum and energy transfer based on the simple-c algorithm. simulations are carried out for the gas pressure station heater of kermanshah city with various tube bundle arrangements. in order to validate the numeric...

In this paper, we tried to interrogate measurements and numbers extrapolated them, through an analytical study,and four relationships that are found called the basic equations for design of Malqaf, containing units their repetition, each which was expressed by a bundle identical straight lines represent line passing principle coordinates, These bundles relate size room, its width, depth height ...

Using Monte Carlo simulations, we investigate the possibility of an orientational melting transition within a "rope" of carbon nanotubes. When twisting nanotubes bundle up during the synthesis, orientational dislocations or twistons arise from the competition between the anisotropic intertube interactions, which tend to align neighboring tubes, and the torsion rigidity that tends to keep indivi...

A 25 year old man underwent electrophysiology study for recurrent symptomatic paroxysmal palpitations. There were no documented episodes of supraventricular tachycardia on surface ECG. Delta waves were absent on baseline ECG. A decapolar catheter was placed in the coronary sinus with the distal and proximal pair of electrodes configured as CS 1-2 and CS 9-10 respectively. Quadripolar catheters ...

transcatheteraortic valve implantation, first introduced in 2002, has been established as an alternative modality for patients deemed not suitable for open-heart surgery. the anatomical vicinity of the atrioventricular node and the his bundle to the non-coronary and rightcoronary aortic cusps predisposes patients to conduction abnormalities in case of severe calcification or mechanical trauma d...

We introduce additively-weighted straight skeletons as a new generalization of straight skeletons. An additively-weighted straight skeleton is the result of a wavefront-propagation process where, unlike in previous variants of straight skeletons, wavefront edges do not necessarily start to move at the begin of the propagation process but at later points in time. We analyze the properties of add...

We characterize the natural diagonal almost product (locally product) structures on the tangent bundle of a Riemannian manifold. We obtain the conditions under which the tangent bundle endowed with the determined structure and with a metric of natural diagonal lift type is a Riemannian almost product (locally product) manifold, or an (almost) para-Hermitian manifold. We find the natural diagona...

bubble columns are gas- liquid contactors that are widely used in chemical and bio- chemical industries. high mixing that result in high heat and mass transfer rates are amongst their advantages. heat transfer in a bubble column having a bundle of heaters investigated and the variation of heat transfer coefficient with variation in heaters pitch to diameter ratios in a bundle of heaters reporte...

Fast and reliable bundle adjustment is essential in many applications such as mobile vision, augmented reality, and robotics. Two recent ideas to reduce the associated computational cost are structure-less SFM (structure from motion) and incremental smoothing. The former formulates the cost function in terms of multi-view constraints instead of re-projection errors, thereby eliminating the 3D s...

Let $p:Xlo B$ be a locally trivial principal G-bundle and $wt{p}:wt{X}lo B$ be a locally trivial principal $wt{G}$-bundle. In this paper, by using the structure of principal bundles according to transition functions, we show that $wt{G}$ is a covering group of $G$ if and only if $wt{X}$ is a covering space of $X$. Then we conclude that a topological space $X$ with non-simply connected universal...