In situ high temperature oxidation analysis of Zircaloy-4 using acoustic emission coupled with thermogravimetry

High-temperature acoustic emission tests using lithium niobate piezocomposite transducers

Acoustic emission (AE) analysis is used for testing materials in structural components and machinery. Acoustic emission frequently consists of ultrasound in the frequency range 100 kHz to 1 MHz, generated either from growing cracks or from mechanical failure in rotating machinery. In the case of crack growth, individual AE events correspond to the release of elastic energy as the crack grows st...

In-situ Corrosion Damage Detector Using Acoustic Emission

This paper aims to present the newly designed acoustic emission AE instrument for the in-situ monitoring of corrosion damages of aircraft structures. The work was theoretically based on the combination of modal AE theory and AE parameter analysis technique. Previous research had shown that identification of corrosion AE and background noise by modal acoustic emission(MAE) technique was possible...

Study of the Frictional Surface Damage Using Acoustic Emission Method

In this study, the change at rubbing surfaces has been investigated experimentally using an acoustic emission signal monitoring system. A steel ring is slipped on the surface of  a metallic sheet to simulate frictional conditions. The mechanical disturbances caused by the movement of the ring produce stress waves propagating along the sheet surface. The out of plane displacement of the sheet su...

Preferential Field Evaporation during Atom Probe Analysis of Zircaloy-4

analysis of power in the network society

اندیشمندان و صاحب نظران علوم اجتماعی بر این باورند که مرحله تازه ای در تاریخ جوامع بشری اغاز شده است. ویژگیهای این جامعه نو را می توان پدیده هایی از جمله اقتصاد اطلاعاتی جهانی ، هندسه متغیر شبکه ای، فرهنگ مجاز واقعی ، توسعه حیرت انگیز فناوری های دیجیتال، خدمات پیوسته و نیز فشردگی زمان و مکان برشمرد. از سوی دیگر قدرت به عنوان موضوع اصلی علم سیاست جایگاه مهمی در روابط انسانی دارد، قدرت و بازتولید...