Search results

Since the importance role of ultrasonic tomography (UT) in industry, especially in oil industry, to produce noninvasive and nondestructive plane images, research on UT system with a metal pipe conveyor is investigated. The produced cross-sectional images are used for detecting the concentration of solid and liquid mixture inside the pipe, noninvasively. In practice, due to application of metal pipes as the conveyor of oil mixture so the capability of manufacturing an UT system with a metal pipe is investigated in this paper. The paper aims to discuss these issues.

Finite element software (COMSOL Multiphysics 3.5) for visualizing the structure of pipe with mounted sensors on the periphery of the pipe is used. The manner of ultrasonic wave propagation on different layers on various frequencies and finding the time of flight for transmission mode signal and lamb mode signal are achieved by the means of done simulations. Finding the proper ultrasonic sensor base on its efficiency is the main step of designing an UT system. This is done by estimating the resonance frequency of sensor due to the manner of ultrasonic wave propagation in different frequencies shown in simulation results.

Due to simulation results, lamb wave is a permanent propagation mode of ultrasonic wave which makes interference in measuring process of straight path signal and it is impossible to remove. Relief of the mentioned problem finding an optimum frequency to decrease the affection of lamb wave in detecting point. Optimum frequency of ultrasonic wave to satisfy the objective is 45 kHz which is measured by considering of mathematic of ultrasonic wave propagation in different layers. The reaching time of straight path signal and lamb wave signal in opposite sensor as the receiver are 5.5 and 4.6 μs, respectively.

This investigation is the first step to perform the UT in a noninvasive method to produce the cross-sectional images of metal pipe. Due to the wide application of metal pipes as the conveyor of the liquids/gases, metal pipe for the UT application is studied in this research.

This study aims to identify the significant scientific actors, reveal the intellectual structure and explore essential features for future research direction in Sharia governance studies.

The study applies a hybrid review combining bibliometric analysis and content analysis. It uses Rstudio (biblioshiny), VOSviewer and Microsoft Excel to analyze 457 articles published in 206 journals indexed by Scopus and/or Web of Science during the period of 1985 until the end of 2022.

The paper discovered four distinct streams of Sharia governance studies: structure of Sharia governance, Sharia governance and risk management, Sharia governance and sustainability and the effect of Sharia governance toward firm’s financial performance. Furthermore, it derives and summarizes 26 main research questions for future studies.

In terms of theoretical implications, the finding contributes to the general literature on Sharia governance by conducting bibliometric analysis and content analysis. In terms of practical implications, this study suggests that Sharia governance should be strengthened by the management of Islamic banks and other Islamic-based businesses.

To the best of the authors’ knowledge, this study is among the early studies using a hybrid review on the topic of Sharia governance, allowing future researchers in this field to capture the trends and progress of current literature as well as the research gaps to be filled in by future researchers.