OBJECTIVE This study aimed to compare the frequency of dentinal microcracks after root canal shaping with 2 reciprocating (Reciproc and WaveOne) and 1 combined continuous reciprocating motion twisted files adaptive (TFA) rotary system. MATERIALS AND METHODS Ninety molars were chosen and divided into three groups of 30 each. Root canal preparation was achieved by using Reciproc R25, Primary Wa...

Carbon fiber reinforced polymer laminates are increasingly used in the aerospace and civil engineering fields. Identifying cracks in carbon fiber reinforced polymer laminated beam components is of considerable significance for ensuring the integrity and safety of the whole structures. With the development of high-resolution measurement technologies, mode-shape-based crack identification in such...

Vibrothermography often employs a high-power actuator to generate heat on a specimen to reveal damage, however, the high-power actuator brings inconvenience to the application and possibly introduces additional damage to the inspected objects. This study uses a low-power piezoceramic transducer as the actuator of vibrothermography and explores its ability to detect multiple surface cracks in a ...

The boundary element method (BEM) has proven to be an efficient approach for crack analysis in fracture mechanics, while its versatility application problems of complex structures with irregular boundaries deserves further attention. In this study, improve the applicability analysis, a cracked superelement is first established BEM model near-crack region, and problem then solved within frame fi...

We analyzed broadband and low-frequency events recorded on Mars made the first detection of horizontally polarized shear wave reflections, which help constrain crustal structure at NASA's InSight lander site. Coherent signals from five well-recorded marsquakes appear to be independent focal depth are consistent with SH-wave reflections off topmost interface (8 ± 2 km). This phase confirms exist...

Sand-®lled cracks from the Lower Fine-grained Quartzite of Dalradian (late Proterozoic) age on the Island of Islay, western Scotland, may be divided into two main types, both of which form orthogonal and non-orthogonal closed patterns on bedding surfaces. Type 1 cracks are short and lenticular in cross-section, contain sand which had been injected downwards, and are found on the bottoms of cros...

Two-dimensional weakly-singular Symmetric Galerkin Boundary Elements (SGBEMs) are developed, following the work of [Han and Atluri (2003)], using non-hypersingular integral equations for tractions. Specifically, the present 2D SGBEM is used to compute the stress intensity factors for arbitrary-shaped line cracks, including embedded, edge, branching, and intersecting cracks. The computed stress ...

Indentation cracks on ceramics are frequently used not only for the semi-empirical determination of the fracture toughness KIC but also as a method for generating semielliptical surface cracks to be used in as starting cracks in fracture and fatigue studies. Tetragonal zirconia stabilized with 3 % mol of yttria (3Y-TZP) is a biocompatible ceramic with good mechanical properties which is used in...

DETECTING DEFECTS IN CHERRIES USING MACHINE VISION By Patchrawat Uthaisombut This thesis describes machine vision procedures which are able to classify defective cherries from non-defective cherries. Defects can be divided into bruises, dry cracks, and wet cracks. Bandpass lters that enhance the intensity contrast between bruised and unbruised cherries are determined. An optimum combination of ...

The dilemma of diagnosing and possibly treating dentinal cracks continues to present a challenge in endodontics. The purpose of this in vitro study was to compare the effectiveness of transillumination and dyes in identifying root-end dentinal cracks. Fifty maxillary central incisors were decoronated, and the canals were instrumented to an ISO size 50 at the working length. The apical 3 mm of t...