PKRU SciTech Journal

The Adsorption of Methylene Blue Dye Using Pineapple Peel Waste

Areerat Sombatphutthakun — 2025-03-27

The aim of this research is to investigate the adsorption of methylene blue dye using pineapple peel waste, with the goal of applying it to wastewater treatment and dye removal from wastewater. Various parameters, such as contact time, initial concentration, and temperature, were investigated. The results showed that the amount of methylene blue dye adsorbed increased as the initial concentration increased. The adsorption amount was 109.77 mg/g at an initial concentration of 500 mg/L. Adsorption reached equilibrium within 2 hours of contact time. Different temperatures had no effect on the amount of adsorption. The Freundlich and Langmuir isotherm models were used to determine adsorption constants, with the Langmuir isotherm model providing the best fit. The correlation coefficient (R) was 0.9901, and the maximum adsorption capacity was 123.46 mg/g.

Effects of Material Shape and Air Resistance Area on Damped Oscillation of Spring Mass System

Vilaiporn Luksameevanish — 2025-03-27

This research aims to study the influence of the shape and size of air resistance areas on the period of oscillation and the air damping constant in a spring-mass system using video recordings from a mobile phone camera and analysis with the Tracker program. The air resistance areas are made from future board and consist of three shapes: equilateral triangle, square, and circle. The results show that the vertical oscillation period of the spring-mass system, with a constant total mass of 180 grams, is independent of the shape of the air resistance area but tends to increase with area size, following the equation T(s)=1.2525+5.3254x10^-5A, where A represents the air resistance area ranging from 25–707 square centimeters. The air damping constant increases with area, following a second-order polynomial equation, and depends on the shape of the air resistance area, with values ranging between 1 and 17 mN·s/m. The air damping constant for square-shaped areas is slightly higher than that of equilateral triangles and circular areas, respectively.

The Development of a Ventilator Counting System Based on the Internet of Things for Hospitals

Pranomkorn Choosri — 2025-03-27

The research focused on developing a counting system for spare ventilators in the emergency room of a hospital in Bangkok using Internet of Things (IoT) technology. The system aimed to prevent ventilator shortages during emergencies and reduce the workload of staff who would otherwise need to manually check the ventilator count. It was designed to count ventilators using object-detection infrared sensors and transmit the data via Wi-Fi, which was then displayed on a webpage. Hospital staff could continuously monitor the remaining number of ventilators, and a notification system via the Line application alerted them when the number of ventilators dropped below a set threshold. This allowed staff to promptly replenish ventilators as needed. The test results demonstrated that the sensors detected ventilators with 97% accuracy, while the alert system performed with 100% accuracy. For future development, improvements are expected in the aesthetic presentation of the website and the connectivity of devices in areas without wireless internet access.