In the electromechanical impedance (EMI) method, the PZT patch performs the functions of both sensor and exciter. Due to the high frequency actuation and non-model based characteristics, the EMI method can be utilized to detect incipient structural damage. In recent years EMI techniques have been widely applied to monitor the health status of concrete and steel materials, however, studies on ap...

The collapse of young massive stars or the coalescence of a black holeneutron star binary is expected to give rise to a black hole-torus system. When the torus is strongly magnetized, the black hole produces electron-positron outflow along open magnetic field-lines. Through curvature radiation in gaps, this outflow rapidly develops into a eγ-wind, which is ultra-relativistic and of low comoving...

Received 4 November 2014 Accepted 1 December 2014 Abstract This study evaluated the depth of cure (DOC) of recently introduced resin composites for posterior use, bulk filled flowable composite (SureFil® SDR® flow DENTSPLY Caulk) at different depth. 30 specimens were prepared and divided into two Groups,Group 1: specimens with 2 mm depth, Group 2: specimens with 4mm depth. The composite specime...

it is now generally recognized that anaerobic bacteria may be involved in most human bacterial infections that follow any form of surgery or are related to those body sites that have a large anaerobic population. anaerobes must therefore be sought in a wide variety of clinical specimens. in this study, 3015 specimens of patients (1684 male and 1331 female) with periodontitis (160 cases), abcess...

In the present research, the mixed-mode fracture mechanics analysis in a plate with central hole under tensile loading is considered. It is assumed that a plate containing two symmetrical hole-edge cracks is bonded with two dissimilar planes. The stress intensity factors at the crack tips are calculated. The problem is modeled in Casca software and this model is analyzed with Franc software. Th...

Roll forming process is used for manufacturing sheet metal parts by successive bending and creating the final shape with gradual deformation. In this article, deformation of a pre-punched sheet due to the roll forming process was studied. Two main defects in the roll forming process are ovality of holes and bow defect. The ovality of the hole is influenced by the process parameters including sh...

We explore the concept of metastability or almost-invariance in open dynamical systems. In such systems, the loss of mass through a “hole” occurs in the presence of metastability. We extend existing techniques for finding almost-invariant sets in closed systems to open systems by introducing a closing operation that has a small impact on the system’s metastability.

Identification of mechanical parameters is still a challenge on real structures. With the improvement of optical full field measurement techniques, it becomes easier, but in spite of many publications showing the feasibility of such methods, experimental results are still scarce. We present here a first step towards a global approach of mechanical identification for composite materials. The cho...