This paper looks at axioms for convexity, and shows how they can be applied to discrete spaces. Two structures for a discrete geometry are considered: oriented matroids, and cell complexes. Oriented matroids are shown to have a structure which naturally satisfies the axioms for being a convex geometry. Cell complexes are shown to give rise to various different notions of convexity, one of which...

Stair pressurization systems are designed to create a smoke-proof barrier, preventing the ingress of smoke into staircases within buildings. In tall buildings over 25 m, evacuation strategies can utilize phased or simultaneous evaluation multiple storeys. This paper examines performance stair with differing number doors open starting from two doors, an incremental step up total 10 shaft. Simula...

the complexation reaction between 1,13-bis(8-quinolyl)-1,4,7,10,13-pentaoxatridecane (kryptofix5) ligand with zn2+, ni2+, co2+, pb2+, mn2+ and cu2+ ions were studied conductometrically in different acetonitrile-nitromethane (an-nm) and acetonitrile-methanol (an-meoh) mixtures. the formation constants of the resulting 1:1 complexes were calculated from the computer fitting of the molar conductan...

Assessment of the annual radon concentration is often required in indoor surveys territories and individual dwellings for comparison with reference levels, studying factors affecting accumulation dwellings, assessment exposure epidemiological studies, etc. The were carried out multistorey buildings eight Russian cities using solid state nuclear track detectors an period three months. For these ...

Introduction: The present study aimed to present a numerical analysis of the penetration depth,  specific absorption rate (SAR), and temperature rise in various eye tissues with varying distance between radiation source and exposed human eye tissues (i.e., cornea, posterior chamber, anterior chamber, lens, sclera, vitreous humor, and iris) at frequencies of 900 and1800 MHz. Materials and Method...