Journal of Opto-Electro-Medic Science

Economical instrumentation utilising ultrasonic guided waves on threaded steel with a USB oscilloscope

2025-02-08T11:08:22+07:00

Guided ultrasonic wave is a diagnostic method that utilizes high frequency wave propagation to analyze the physical condition of a material in real-time. This research aims to develop economical instrumentation using guided ultrasonic waves on threaded steel with the help of a USB oscilloscope. Threaded steel, which is used as reinforcement in construction structures, often develops cracks that affect its strength and reliability. Therefore, there is a need for an efficient evaluation method to identify the condition of this material. The system developed in this study overcomes measurement challenges at high frequencies, such as significant noise and complex propagation modes, by utilizing narrow bandwidth signals. The performance of the system is evaluated through analysis of signal to noise ratio, averaging effect, filtration, and initial gain. The results show that techniques such as averaging, bandpass filtration, and gain using a pre-amplifier successfully improve measurement accuracy and reliability despite the limitations of USB oscilloscopes in signal capture quality. These findings provide a reliable low-cost instrumentation alternative for monitoring and physical characterization of threaded steel in civil engineering applications.

Analysis of fibre optic evanescent wave sensor for the rapid detection of organic pollutants in drinking water sources

2025-02-08T11:15:08+07:00

Fibre optic evanescent wave (FOEW) sensor is an optical-based technology used to detect organic pollutants in drinking water sources quickly and efficiently. It utilizes the interaction of evanescent waves with a sensitive coating to identify optical changes that indicate the presence of organic contaminants. This research examines the working principle of the FOEW sensor, including the ability to detect volatile organic compounds in water at low concentrations of up to 10 ppb within five minutes. FOEW technology offers various advantages, such as corrosion resistance, fast response, low cost, and ease of real-time online measurement. Results show that FOEW sensors have high sensitivity for detecting organic contaminants and provide accurate data for water quality monitoring. These findings demonstrate the great potential of FOEW sensors as a reliable environmental monitoring tool, particularly in detecting water pollution due to human activities.

Application of stereoelectroencephalography utilising single pulse electrical stimulation method for brain connectivity

2025-02-08T13:55:02+07:00

Stereoelectroencephalography (SEEG) is a technique that allows direct observation of brain activity through electrodes implanted into the brain. This study utilized the single pulse electrical stimulation (SPES) method to explore brain connectivity structurally, functionally, and effectively. Results showed that SEEG with SPES was able to record pulse evoked potentials (PEP) indicating connections between neurons with high accuracy. Connectivity analysis identified PEP features, such as C1 peak amplitude, that significantly correlated with structural connection strength. However, connectivity models show limitations in areas with low connectivity or complex anatomy, such as brain sulci. In addition, the three-dimensional network topology showed improved conductivity resolution around the electrodes. This study underscores the need to improve methodologies to improve precision and resolution in brain connectivity assessment, as well as stimulation procedures.

Impact of gamma irradiation on the properties of fiber Bragg grating

2025-02-08T14:11:00+07:00

Fiber Bragg grating (FBG) is an optical sensor used to detect environmental changes, such as temperature, pressure, and radiation. This study analyzes the impact of gamma-ray irradiation on the shift of Bragg reflection wavelength in FBG optical fibers at various temperatures. The results show that increasing temperature from 18°C to 40°C before gamma irradiation causes a Bragg wavelength shift of about 5.48 pm/°C. Gamma-ray irradiation with a cumulative dose of 22.85 kGy for 124 min at 35°C resulted in a radiation dose-dependent Bragg wavelength shift, with a value of about 5.25 × 10^-3 pm/Gy. After the irradiation was stopped, the Bragg reflection wavelengths on the FBG fibers showed a recovery of up to 84.4% for the buffer fiber and 36.2% for the reference fiber. These findings provide important insights into the behavior of FBG sensors in an environment of gamma radiation and temperature fluctuations, making them potential for applications in extreme condition monitoring.

Factors contributing to slice loss in small-angle X-ray scattering tensor tomography in real space

2025-02-08T14:20:16+07:00

X-ray small-angle scattering tensor tomography (SAXSTT) technique is an innovative method that enables 3D tomographic reconstruction of large-volume voxels non-destructively. This study identifies factors that affect slice loss in SAXSTT in real space. Results show that the quality and resolution of the resulting images are strongly influenced by the signal to noise ratio (SNR), absorption, as well as scattering in the sample. In addition, parameters such as collimator and slice thickness during CT scanning prove crucial for obtaining optimal image results. Reconstruction using SAXSTT shows great potential in high-precision material analysis, especially in applications where sample integrity is required to be maintained.