The influence of different voltage measurement and current injection configurations on the quality of image reconstruction in electrical impedance tomography (EIT) was investigated using numerical simulations. Adjacent and opposing techniques were systematically used to examine their effectiveness in voltage acquisition and current delivery. The simulation model employed 16 equally spaced electrodes arranged around a circular domain, with an injected alternating current of 1 mA at a frequency of 50 kHz. A circular object with a conductivity of 0.9 units was sequentially positioned at five distinct locations within the imaging domain, each spaced 0.05 units apart. The reconstructed images were analyzed for positional accuracy and contrast resolution. While each configuration offers specific advantages, they exhibit inherent limitations depending on the application. The results of this study enable the understanding of the trade-offs involved in selecting electrode drive and measurement strategies for optimizing image quality in EIT systems.

The atomic mechanism of the melting process of the free-standing h-BN is studied using Molecular dynamics simulation. The critical value of the Lindemann criterion for the free-standing h-BN is defined at 0.0326 which is used to classify solid-like and liquid-like atoms. The influence of the edge types on the melting process is observed based on the study of the free-standing hexagonal boron nitride (h-BN), armchair h-BN nanoribbon, and zigzag h-BN nanoribbon using molecular dynamics simulation. Due to dangling bonds at the armchair edge, the phase transition from crystalline to liquid in armchair h-BN nanoribbon occurs at a lower temperature (3700 K) than in zigzag h-BN nanoribbon (4200 K), and the free-standing configuration (4550 K). At the melting temperature, most B atoms in the zigzag h-BN nanoribbon exhibit coordination numbers of one or two, whereas most B atoms in the armchair h-BN nanoribbon and the free-standing h-BN have a coordination number of zero.

The study uses a low-cost, dual Geiger-Müller (GM) tubes coincidence detection device in an outdoor environment to evaluate the relationship between cosmic muon flux on zenith angle. Coincidence occurrences decreased from 484 counts at vertical alignment to 47 counts at horizontal alignment, with zenith angles of 0°, 30°, 45°, 60°, and 90°. Under normal values at sea level, the measured directional muon flux at 0° was 1.301 muons/cm²/min. An exponent of n = 1.063 ± 0.107 was obtained by fitting the angular dependency to a cosine power law via a Bayesian Markov Chain Monte Carlo (MCMC) approach. The result indicates a qualitative agreement with a cosine-based angular distribution under practical constraints, despite the fact that this value is less than the theoretical expectation (n ≈ 2). The setup achieved a Noise Rejection Ratio (NRR) of 0.373% and a Directional Index (DI) of 0.804, indicating moderate directional selectivity and noise suppression. This study demonstrates the viability of Geiger-Müller detectors in basic cosmic ray research and educational contexts.