Shima Haghgooyan, Fatemeh Ostovari, Hakimeh Zare, Zahra Shahedi,
Volume 16, Issue 1 (1-2022)
Abstract
ta charset="UTF-8" >Silk fibroin (SF) is a natural material that has received special attention due to its excellent mechanical and electrical properties. Nowadays, it is tried to improve the properties of SF by adding other nanomaterials such as graphene oxide (GO). Here, we extracted SF from silk cocoon and studied its properties in pure state and in the combination with graphene oxide (SF/GO). The results have shown that the presence of graphene oxide in the structure of fibroin increases the random winding formation of SF. The measurements show that the water content has a great effect on the properties of SF and SF/GO films. The contact angle (less than 70) indicates the hydrophilic property of these films. In addition, in times greater than 50 seconds, the contact angles drop to 27° and 5° for SF and SF/GO respectively. Also, the surface resistance of the completely dried SF/GO film increases from 50 kW/sq to 220 kW/sq for 42% wt water content.
Ehsan Adibnia, Majid Ghadrdan, Mohammad Ali Mansouri-Birjandi,
Volume 17, Issue 2 (6-2023)
Abstract
This research addresses the complexities and inefficiencies encountered in fabricating fiber Bragg gratings (FBGs), which are crucial for applications in optical communications, lasers, and sensors. The core challenge lies in the intricate relationship between fabrication parameters and the FBG's physical properties, making optimization time-consuming. To circumvent these obstacles, the study introduces an artificial intelligence-based approach, utilizing a neural network to predict FBG physical parameters from transmission spectra, thereby streamlining the fabrication process. The neural network demonstrated exceptional predictive accuracy, significantly reducing the parameter prediction time from days to seconds. This advancement offers a promising avenue for enhancing the efficiency and precision of FBG sensor design and fabrication. The research not only showcases the potential of artificial intelligence in revolutionizing FBG production but also contributes to the broader field of optical technology by facilitating more rapid and informed design decisions, ultimately paving the way for developing more sophisticated and sensitive FBG-based applications.
Morteza Janfaza, Hamed Moradi, Arsalan Jalil,
Volume 17, Issue 2 (6-2023)
Abstract
In this study, we present the findings derived from our simulation and experimental investigation of a distributed optical fiber acoustic sensor. The proposed sensor operates by utilizing the self-interference of Rayleigh backscattering. When the optical pulse propagates through the optical fiber, the phase of the Rayleigh backscattered light changes at the location where the acoustic signal is present. This phase change is then amplified through the self-interference of two Rayleigh backscattered beams in the Michelson interferometer scheme. This study aims to present the Phase Generated Carrier (PGC) demodulation method along with the arctangent function (ATAN) and the Coordinate Rotation Digital Computer (CORDIC) algorithm. This method offers a simple and efficient algorithm for computing hyperbolic and trigonometric functions. The system allows for the detection of acoustic waves caused by sinusoidal disturbances with a spatial resolution of approximately 20 m.
