Introduction. Experimental studies of crack formation and limit equilibrium a reinforced concrete floor slab-shell, developed by the authors, were carried out. Materials methods . The out on models made scale 1:5. Results. During tests, three stages stress-strain state established: first is elastic stage tensile work in lower part longitudinal contour ribs; second opening cracks; third destruct...

Supernumerary lumbar ribs are usually asymptomatic and discovered incidentally during routine diagnostic radiography. During a routine inventory of the research skeletal repository at the University of the Witwatersrand, a rare case of bilateral supernumerary ribs on the first lumbar vertebra was observed. The skeletal specimen belonged to a 70-year-old African male whose recorded cause of deat...

A rapid prototyping method is invented, which works on a specific data structure produced by an optical metrology technique: 360-degree surface profile scanning. A computer algorithm takes an object profile data, restructure the format, generate horizontal and vertical ribs, lay out the ribs on a 2D canvas and output the geometries to a file format compatible with laser cutters. A laser cutting...

The formation of oblique ribs of bivalve shells usually has been attributed to processes of reaction-diffusion of morphogens from cell to cell at the mantle margin or neural activation and lateral inhibition in the mantle. In particular, such ribs appear with high rates of lateral diffusion. Nevertheless, theoretical models fail to explain either partially or wholly some varieties of oblique ri...

This paper experimentally and numerically investigated the heat transfer and friction characteristics of microfluidic heat sinks with variously-shaped micro-ribs, i.e., rectangular, triangular and semicircular ribs. The micro-ribs were fabricated on the sidewalls of microfluidic channels by a surface-micromachining micro-electro-mechanical system (MEMS) process and used as turbulators to improv...

Distinguishing human from non-human bone fragments is usually accomplished by observation of gross morphology. When macroscopic analysis is insufficient, histological approaches can be applied. Microscopic features, like plexiform bone or osteon banding, are characteristic of non-humans. In the absence of such features, distinguishing Haversian bone as either human or non-human proves problemat...

The etiology of idiopathic scoliosis is still a matter of debate as its common cause had not been found. But some basic principles in its initiation and progression do exist. The curvature of the spine is always accompanied by rotation of the vertebrae and rib cage as ribs are connected by intercostal muscles and cannot spread apart on the convex side when the spine bends. The rib cage rotates ...

Temperature distribution in tissues behind ribs produced by weakly focused ultrasound had been calculated using Pennes bioheat equation and the validity of the theoretical model was experimentally confirmed in vitro using porcine live. We found that the position of the maximum temperature in tissue is strongly influenced by the distance between the transducer and ribs, while the gap between rib...

Solar air heater is a type of heat exchanger which transforms solar radiation into heat energy. The thermal performance of conventional solar air heater has been found to be poor because of the low convective heat transfer coefficient from the absorber plate to the air. It is attributed to the formation of a very thin boundary layer at the absorber plate surface commonly known as viscous sub-la...