the new non-conventional cutting process by the use of thermal shock is a convenient procedure for cutting the brittle materials such as glasses and ceramics. this method is based on the application of localized thermal shock to brittle materials by the use of hot air jet, which induces thermal stresses at the tip of an existed pre-crack. due to the thermo-elastic behavior of materials, the pre...

a new approach is proposed to model a crack in orthotropic composite media using the extended finite element method (xfem). the xfem uses the concept of partition of unity in addition to meshless basic idea of approximating a field variable by its values at a set of surrounding nodes. as a result, higher order approximations can be designed with the same total number of degrees of freedom. in t...

In this paper, the extended finite element method (XFEM) is employed to investigate the statics and vibration problems of cracked isotropic bars and beams. Three kinds of elements namely the standard, the blended and the enriched elements are utilized to discretize the structure and model cracks. Two techniques referred as the increase of the number of Gauss integration points and the rectangle...

In this paper, controlling the location of the tip of an L-shape beam under gravity field is investigated. The beam is covered with piezoelectric patches. The gravity filed moves the tip of beam downward and the actuators with induced voltage move the tip to the previous location. to optimize the best location and voltages for actuators, the particle swarm optimization algorithm code is develop...

A 31 year-old man with a biopsy-proved retroperiotoneal yolk sac tumor was referred to our clinic. Physical examination revealed a thum- tip sized left supra-clavicular mass, a huge right abdominal mass and a tiny hard mass of the right testis. On CT scan, the abdominal tumor, 13 cm in diameter, encircled the inferior vena cava. Serum levels of LDH, AFP and hCG-beta were 2,585 U/l, 19,922 ng/ml...

Displacing an object with a hand-held rod provided a simple paradigm for studying tool use. The authors asked how reaching was affected by manipulations of rod properties. Adults held a rod (length =.10 to 1.5 m), with its tip in the air; walked toward an object on a table; chose a place to stop; and displaced the object with the rod's tip. In 3 experiments (Ns = 9, 22, and 17 participants), th...

Numerical methods such as boundary element and finite element methods are widely used for the stress analysis in solid mechanics. This study presents boundary element method based on the displacement discontinuity formulation to solve general problems of interaction between hydraulic fracturing and discontinuities. The crack tip element and a higher order boundary displacement collocation techn...

J Postgrad Med 2004;50:287-8 55-year-old man presented to the ENT outpatients’ department with a mass at the tip of his nose, which bled occasionally. On examination, his pulse was 80/ minute; respiration was normal and blood pressure was 130/ 90 mm of Hg. The nasal mass was nodular, greyish black, covered with skin, measured 3x 3 cm, and bled on touch (Figure 1). Despite being advised surgical...

Mass spectrometry imaging (MSI) and in-situ single cell mass spectrometry (SCMS) analysis under ambient conditions are two emerging fields with great potential for the detailed mass spectrometry (MS) analysis of biomolecules from biological samples. The single-probe, a miniaturized device with integrated sampling and ionization capabilities, is capable of performing both ambient MSI and in-situ...

This study aimed to investigate the influence of bleeding position a self-circulating casing on aerodynamic performance transonic centrifugal compressor. Three types structures with positions 11% Ca (the axial chord length blade tip), 14% and 20% from leading edge were studied by using numerical simulation method, Krain impeller taken as research object. It was found that all three self-recircu...