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A microwave NDT method based on guided electromagnetic wave is described in order to detect longitudinal crack and evaluate its location in steel pipe. To detect longitudinal crack in pipe, suitable guided-mode should be propagated in the inspected pipe with crack. For this purpose, first and dominant circular TE 11 -mode is sent to the system by using a mode-converter. Mode-converter is used to convert rectangular TE 10 -mode to the circular TE 11 -mode. A network analyzer, which is a generator and receiver of the microwaves designed to process the magnitude and phase of the reflected and transmitted waves was used to generate continues signal and to measure the amplitude of reflection coefficient. The goal of this investigation is to demonstrate the capability of this technique for detecting longitudinal cracks in piping system with high speed. More emphasis is put on the evaluation of crack location by measuring time of flight (TOF) of the reflected waves from the crack. The results for two crack locations at several plunger positions either in frequency domain or time domain for measuring TOF of the waves are presented. The experimental results of TOF are compared with calculations to show that by knowing TOF of the reflected wave, it is possible to predict crack locations. The evaluated results of TOFs are shown to agree well with the calculated ones and crack locations can be estimated with error less than 0.13%.

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In this paper, we adopt the Verlinde hypothesis on the origin of gravity as the consequence of the tendency of systems to increase their entropy and employ the Tsallis statistics. Thereinafter, modifications to the Newtonian second law of motion, its gravity, and radial velocity profile are studied. In addition, and in a classical framework, the corresponding cosmology and also its ability in describing the inflationary phases are investigated.