introduction: the restoration of endodontically treated teeth is a topic that has been studied extensively but it is still a challenge for dental practitioners. the aim of this study was to evaluate fracture resistance, fracture patterns and fracture location of endodontically treated human maxillary premolars restored with direct and indirect composite resin and ceramic restoration. methods: e...

Introduction: To evaluate and compare shear bond strength of self-cure and  light-cure composites using a universal bonding system. Materials and Methods: Superficial coronal dentin of 62 intact extracted  premolars was exposed and bonding agent (All-Bond Universal) was applied over the  dentin surface according to the manufacturer instruction (self-etch mode). Then  samples were distribut...

This work aims at developing a genetic algorithm (GA) to pursue the optimization of hybrid laminated composite structures. Fiber orientation (predefined ply angles), material (glass-epoxy or carbon-epoxy layer) and total number of plies are considered as design variables. The GA is chosen as an optimization tool because of its ability to deal with nonconvex, multimodal and discrete optimization...

First-ply failure (FPF) of composite thin-walled columns and frames is investigated in the buckled structure. Elastic behavior is assumed during the pre-buckling and buckling states, and along part of the post-buckling equilibrium path. The Tsai-Hill criterion is employed to identify failure of one ply at one specific location. The technique of analysis is based on evaluation of the post-buckli...

Caterpillar compaction NA compaction, say Ryan Case, YunPei Chang, Nicholas Cozzarelli, Carlos Bustamante, and colleagues (University of California, Berkeley, CA), may work via a cooperative caterpillar-like mechanism. The caterpillar is formed by multiple copies of condensin protein—in this case MukBEF—with each V-shaped condensin contributing two legs. Compaction occurs when the caterpillar’s...

This work explores the postbuckling behavior of a marine stiffened composite plate in presence initial imperfections. The imperfection shapes are derived from buckling mode and their combinations. Thereafter, these applied to model, nonlinear large deflection finite element progressive failure analyses performed ANSYS 18.2 software. Hashin criterion is employed model plate. effect geometric on ...

We find that the classical failure criteria, i.e., maximum normal stress criterion, Tresca criterion, Mohr-Coulomb criterion, and von Mises criterion, cannot satisfactorily explain the tensile fracture behavior of the bulk metallic glass (BMG) materials. For a better description, we propose an ellipse criterion as a new failure criterion to unify the four classical criteria above and apply it t...

SUMMARY In this paper, we propose a novel Web service composition framework which dynamically accommodates various failure recovery requirements. In the proposed framework called Adaptive Failure-handling Framework (AdaFF), failure-handling submodules are prepared during the design of a composite service and some of them are systematically selected and combined with the composite Web service at...

We present an experimentally-based failure criterion for symmetric two-ply plain-weave laminates of carbon-fiber reinforced plastic. The criterion is formulated in terms of six force and moment stress resultants and consists of a set of three inequalities, related to in-plane, bending, and combined in-plane and bending types of failure. All failure parameters in the criterion are measured direc...

because of inhomogeneity and anisotropy of composite materials, defining a unique fatigue criterion to be suitable for different loading conditions is much more difficult in comparison with traditional materials. for this reason many tests on evaluating the damages such as crack density, stiffness reduction and residual strength are used by various researchers to monitor the fatigue process. in...