nowadays cmm machines are widely used in surface measurement and inspection. as inspection results from cmm machine are obtained by the means of measuring surfaces with direct contact, they are more precise than non-contact method (like optical measurement). however, cmm machines give more reliable and accurate results rather than non-contact methods but also these results come with error when ...

Introduction: Micro-perforated absorbents are one of the structures that are widely used nowadays. The sound absorption mechanism is performed by viscous energy losses in the cavities on the plate. In this study, the acoustic properties of non-flat perforated panels in oblique angle was investigated in numerical method. Material and Methods: This paper examined the effect of the surface shape ...

The present paper reports the laminar fluid flow and heat transfer of a heated array of circular-perforated and solid fins mounted over a flat surface using the finite-volume method. One to four circular cross-sectional perforations are made along the length of the fins. The SIMPLE algorithm is used for pressure-velocity coupling and the second order upwind technique is employed to discreti...

A trisonic wind tunnel has been modified to improve its flow quality when operating at transonic speeds through perforated walls and side suctions. The usefulness of such a perforated wall, already known, is reduction of the blockage effect as well as the shock elimination. Two types of perforated walls have been used in this investigation. The first wall had a porosity of about 22% and the hol...

A technique, the "Loma Linda pouch," is introduced for repairing the perforated maxillary sinus membrane during sinus grafting procedures. A collagen membrane is placed against the perforated site and subsequently covers the internal surface of the maxillary sinus. The collagen membrane is then folded along the lateral access window to form a pouch that surrounds and isolates the graft material.

in this work, laser bending of perforated sheets has been investigated numerically. laser bending of perforated sheets is more complicated than non-perforated sheets due to their complex geometries. in this paper, laser bending of perforated sheets is studied numerically in the form of thermo-mechanical analysis with abaqus/implicit code. for this purpose, the effects of process and sheet param...

Fins are protrusions on a heat transfer surface to augment heat transfer rate from it. The increase in area exposed to convection in case of finned surfaces results in increased heat transfer rate. In this study heat transfer characteristics of a pin fin with perforation is numerically analyzed. A pin fin is fabricated and experiments are done under forced convection conditions. The experimenta...

PURPOSE The purpose of this study was to evaluate the results of the repair of perforated sinus membranes with resorbable collagen membrane. MATERIALS AND METHODS A split-mouth design was followed. Twelve subjects requiring bilateral sinus grafting were included in the study; one site had been accidentally perforated during sinus augmentation and the other site had not been perforated. The pe...