PKRU SciTech Journal

The Adsorption of Methylene Blue Dye Using Pineapple Peel Waste

Areerat Sombatphutthakun, Sirithon Sinpiang, Suwakon Janta — Thu, 27 Mar 2025 00:00:00 +0700

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

Thu, 27 Mar 2025 00:00:00 +0700

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 , 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 triangle areas and circular areas, respectively.

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

Pranomkorn Choosri, Sirirat Solos, Tawiwan Sareebot, Po Sinchoo — Thu, 27 Mar 2025 00:00:00 +0700

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.

A Real-Time Hand Gesture Recognition System for Elderly Care Using MediaPipe and Line Application

Ponwana Rattanachuchok, Chulawalee Maneelert — Mon, 09 Jun 2025 00:00:00 +0700

This research presented a real-time hand gesture recognition system for elderly care using MediaPipe and the LINE application. The primary objective was to develop a prototype of a real-time hand gesture recognition system for elderly care using MediaPipe and the LINE application. When predefined hand gestures were detected, the system sent notification alerts to users via the LINE application. The prototype development was divided into two main components: hardware, consisting of a Raspberry Pi 5 and a Raspberry Pi Camera Module 3; and software, featuring a gesture detection notification system integrated with LINE. The innovation effectively identified three specific gestures used for requesting assistance and delivered alerts via the LINE application. Accuracy measurements for the system showed that Gesture 1 ("love") achieved 93%, Gesture 2 ("pointing up") reached 98.5%, and Gesture 3 ("victory") attained 99.5%. This innovation demonstrated its potential applicability in assisting elderly individuals by enabling them to communicate with caregivers using simple hand signals.

Composition and Properties of Red Soil from Surat Thani for Developing Natural Color in Art

Tanupol Chantakul, Arnon Chukaew, Chanya Udompramuan, Wirot Chaowiset — Mon, 09 Jun 2025 00:00:00 +0700

This research aimed to investigate the properties of natural pigments derived from local red soils in Surat Thani Province and establish knowledge for the development of natural clay pigment products. Soil samples were collected from Phanom and Khiri Rat Nikhom districts, focusing on Soil Group 26 (Ao Luk soil series) and Soil Group 34 (Fang Daeng soil series), both known for their distinct red hues. Soil sampling was conducted at three depth levels (0-10, 10-20, and 20-30 cm). The analysis included physical and chemical properties, including soil texture, pH, electrical conductivity, and soil color. The morphology, adhesion structure, and surface characteristics of pigment nanoparticles were examined using a scanning electron microscope (SEM). Mineral components in the soil were analyzed using the X-ray diffraction (XRD) technique. The results revealed that soil from Khiri Rat Nikhom exhibited high potential as a natural pigment source, containing significant amounts of hematite, stilpnomelane, and copper vanadium oxide, which contribute to a deep reddish-brown hue, particularly in the KRN-A area. SEM analysis revealed diverse shapes and sizes of soil particles, affecting their adhesion properties and dispersion on different surfaces. Therefore, red soil from Khiri Rat Nikhom District, Surat Thani Province, which has a high amount of hematite and red-colored minerals, and has an appropriate particle size, can be developed into natural color products for art, especially in the KRN-A area, which has the most outstanding properties. This will help reduce the reliance on synthetic colors, and provide a guideline for using environmentally friendly materials.

Enhancing Productivity Through Object Detection Systems on Production Conveyors in the Carton Milk

Mon, 09 Jun 2025 00:00:00 +0700

This research investigates the application of an object detection system on a conveyor belt for sorting carton milk products. The study involves experimentation, data collection on machine-based sorting processes, and the calculation of energy consumption. The implemented system consists of a 5-meter-long conveyor integrated with industrial cameras and sensors functioning as input devices. When a product moves along the conveyor, the camera and sensor detect the object and send a signal to the PLC (Programmable Logic Controller) to verify its accuracy. The system then sends output signals to direct the carton milk products to the packaging department. The system was programmed to detect three types or colors of milk cartons and was applied to the production line in a dairy factory. The performance of the conveyor system was evaluated at three different speeds: 0.2, 0.4, and 0.6 meters per second. The detection and sorting capacities were found to be 1,200, 2,400, and 3,600 cartons per hour, respectively. The system was applied to a dairy industry case study located in an industrial estate in Phra Nakhon Si Ayutthaya Province. Based on feedback from the case study company, increasing the conveyor speed beyond 0.6 meters per second could further enhance sorting productivity and reduce production costs. The company aims to achieve a target sorting rate of 6,000 cartons per hour.

The Expansion of the Small Universe Model: Balloon

Somyot Srikongrug, Sookpichaya Charrunchon, Chote Nuangnun — Tue, 10 Jun 2025 00:00:00 +0700

This research emphasized on create a model of the expansion of the small universe and study the physical characteristics of the expansion of the small universe, including a comparative study with the theory of universe expansion using balloon technique, which is an easy-to-find material, cheap and convenient for experimentation. The research results found that the experimental data were consistent with theoretical results. The regression velocity and arc length show a linear relationship that corresponds to the equation . The change in the value of the Hubble constant over time is given by . The change of arc length between two points with time (seconds) is given by . Finally, the analysis of the motion of objects on the surface of the balloon expansion found that the experimental results were basically consistent with the theoretical results .