Bulletin of Applied Sciences

Low-cost toilet-based sit-to-stand device for elderly with lower limb weakness

Thanakorn Yootho, Yutthana Pititheeraphab — Tue, 30 Jun 2026 00:00:00 +0700

Falls in the bathroom pose a serious risk to older adults, leading to physical and psychological consequences and a reduced quality of life, including fractures, head injuries, fear of movement, and loss of independence. These falls result from both personal factors, such as muscle weakness, impaired balance, chronic conditions, and medication side effects, and environmental factors, including slippery floors, inadequate lighting, insufficient assistive devices, and unsuitable sanitary fixtures. This research aimed to design and develop a low-cost toilet-based sit to stand device for elderly with lower limb weakness that can be used with both standard and multipurpose toilet bowls. The device supports safe and comfortable transitions between sitting and standing and is designed based on biomechanical principles of the sit-to-stand movement. The system comprises a mechanical unit with a linear electric actuator, an electrical control system, a C-based control program, and a battery-powered energy source. Biomedical engineering tests confirmed correct operation and stable performance of the control and safety systems. Biomedical tests confirmed stable control and safety performance. The device safely supported loads of 10–120 kg. Lifting time ranged from 11.73–16.15 s, while lowering time ranged from 11.14–12.93 s. In 30 volunteers (15 males, 15 females), knee flexion angles decreased after device use from 86.07–89.93° to 60.70–72.90° in males and from 78.10–88.13° to 59.10–67.90° in females, indicating reduced knee joint load during sit-to-stand. These results indicate that the device effectively reduces biomechanical load on the knee joint during the sit-to-stand movement.

An innovative of the portable electric tjanting pen

Apaporn Sinthusarn, Somphon Sincharoenpokai, Kartoon Pengprom — Tue, 30 Jun 2026 00:00:00 +0700

This research aimed to develop a portable electric tjanting pen to replace the traditional tjanting pen, which requires lengthy preparation of melted wax and poses health risks to batik artisans. The study began with a problem analysis, followed by the design of the external structure and internal system, as well as an investigation into alternative materials for batik wax. The process included the construction and development of the portable electric tjanting pen and palm wax sticks, preliminary usability testing, and refinement of the device based on expert recommendations. Additionally, the study assessed the satisfaction of batik artisans using the portable electric tjanting pen. The research results demonstrated that the portable electric tjanting pen could effectively be used to apply wax on batik fabric. When operated at a current of 15 volts in combination with palm wax sticks, the device achieved a maximum continuous writing time of 6 minutes and a maximum writing distance of 1,662 centimeters at a speed of 277 centimeters per minute. The portable electric tjanting pen and palm wax sticks were found to be user-friendly, time-saving by eliminating the need to boil wax, cost-effective in terms of production, and posed no long-term health risks. Moreover, the device is convenient to carry, making it suitable for use by children, youth, and the elderly. The batik artisans who tested the device reported a very high level of satisfaction (x̄ = 4.44, S.D. = 0.69), equivalent to 88.8%.

Improving coconut fiber sheet performance via stepwise chemical treatments

Thitarini Suropan, Surawut Puangmalee, Jarawee Leksuksri — Tue, 30 Jun 2026 00:00:00 +0700

Coconut fibers have gained increasing attention due to their sustainability, eco-friendly characteristics, and potential as a reinforcing component in composite materials. However, coconut fibers possess a hydrophilic nature, a heterogeneous structure, and poor interfacial adhesion with matrix materials. Therefore, surface modification is essential to enhance their properties before application. This research aims to improve the physical, mechanical, hydrophobic, and interfacial adhesion properties of coconut fibers for the development of interior decorative wall panels, using polyvinyl alcohol (PVA) as a binder. Sequential chemical surface treatments were investigated using potassium permanganate combined with sulfuric acid and benzoyl chloride as well as a treatment sequence starting with sodium hydroxide followed by potassium permanganate combined with sulfuric acid and benzoyl chloride. The morphological characteristics of the fibers were analyzed using scanning electron microscopy (SEM) and the elemental composition was detected by energy-dispersive X-ray spectroscopy (EDX). Physical and mechanical properties of the fiber sheets were underwent testing. The sodium hydroxide pre-treatment effectively removed some of the outer layer of fibers that were damaged and peeled off during the grinding process, resulting in improved accessibility of reactive sites for subsequent chemical modifications and reduced water absorption. Subsequent oxidation with potassium permanganate combined with sulfuric acid increased surface roughness and surface area, leading to a significant enhancement in tensile strength and interfacial bonding with the PVA matrix. In the final step with benzoyl chloride treatment, the hydrophilicity was reduced and the flame-retardant properties were improved, although a slight decrease in tensile strength was observed. Overall, the results indicate that sequential chemical modification significantly influences the structural, morphological, physical, and mechanical properties of coconut fibers and coconut fiber sheets. The most effective treatment was the sodium hydroxide pre-treatment followed by potassium permanganate / sulfuric acid oxidation, which provided optimal improvement for composite applications requiring high mechanical strength, reduced water absorption, and enhanced fiber–matrix interfacial adhesion with PVA binders.

Determination of technical measurement uncertainty and method verification for coliform detection using the Multiple Tube Fermentation method in drinking water in sealed containers, ice, and raw water samples

Tue, 30 Jun 2026 00:00:00 +0700

Coliform bacteria are a group of microorganisms commonly used as bacteriological indicators for assessing the microbiological quality and hygiene of water and food products. However, most laboratories in Thailand still lack verification data for microbiological analytical methods in accordance with ISO 16140-3:2021, which is essential for enhancing laboratory competence and supporting ISO/IEC 17025 accreditation. The determination of the Standard Deviation for Intralaboratory Reproducibility (S_IR) and the method verification serves as definitive evidence that a laboratory can competently perform reference methods to ensure accurate and reliable results for clients. This study aimed to evaluate laboratory capability in quantifying coliform bacteria across various water samples, including bottled drinking water, ice, raw water, food-contact surface water, and deionized (DI) water. The evaluation determined the S_IR and the Estimated bias (eBias) using the Multiple Tube Fermentation (MTF) method based on ISO 16140-3:2021 protocol for the verification of reference methods in a single laboratory. Three inoculation levels were evaluated: low (1 cfu/mL), medium (10 cfu/mL), and high (20 cfu/mL). The results revealed an overall S_IR of 0.14. The eBias values for Group (A) samples were 0.00, 0.30, and 0.05 Log₁₀ MPN/100 mL; for Group (B) samples were 0.18, 0.01, and 0.02 Log₁₀ MPN/100 mL; and for Group (C) samples were 0.12, 0.06, and 0.05 Log₁₀ MPN/100 mL, respectively. The method verification demonstrated that both S_IR and the eBias values across all water types complied with the acceptability limit of ≤0.5 Log₁₀ MPN/100 mL specified by ISO 16140-3:2021. This confirms that the laboratory can successfully implement the MTF method according to APHA, AWWA, and WEF standards with high accuracy and reliability. Consequently, these findings support the laboratory's application for ISO/IEC 17025:2017 accreditation and demonstrate that this verified MTF technique is highly suitable for drinking water quality surveillance systems to protect public health.

Performance investigation of a transparent roof forced convection solar drying system for drying Andrographis paniculata

Kotchanipha Yuyen, Sarawut Nabnean — Tue, 30 Jun 2026 00:00:00 +0700

This research investigated the performance of a transparent roof forced convection solar drying Andrographis paniculata (commonly known as “Fah Talai Jone”). The system was designed as a large-scale greenhouse with an area of 3×12 m². The roof structure consisted of alternating transparent and opaque corrugated metal sheets, each measuring 50×120 cm², while the walls were constructed from concrete blocks enclosing all four sides. The ventilation system comprised 6 fans powered by two 80 watt photovoltaic panels. In the experiment, a total of 200 kg of Andrographis paniculata was dried using the system between 8:00 a.m. and 6:00 p.m. The average solar radiation intensity during the experimental period was 366 W/m². Drying system temperature ranged from 36 - 41 °C, which is suitable for herbal processing as it prevents thermal degradation. The initial moisture content of 82% (wb) was successfully reduced to 10% (wb) within only three days. In comparison, natural sun drying achieved a final moisture content of 22% (wb). Thae solar dryer compared to natural sun drying a 40% reduction in drying time. The dried Andrographis paniculata obtained from the solar dryer demonstrated superior quality in terms of bioactive compound retention, color attributes, and a water activity of 0.41, which allows for extended storage stability by reducing the risk of fungal growth. Furthermore, the system effectively prevented insect infestation, rainfall interference, and dust contamination, ensuring a more hygienic and reliable drying process.

Study on the efficiency of automatic village water disinfection system using ultraviolet radiation

Apaporn Sinthusarn, Anucha Sinthusarn — Tue, 30 Jun 2026 00:00:00 +0700

This research study aimed to evaluate the efficiency of an automatic ultraviolet (UV) disinfection system for village tap water, beginning with the system’s design and development and followed by real-world application testing in target communities. The findings revealed that the automatic UV disinfection system effectively functioned and was appropriately designed for integration into various village tap water systems across Thailand. The system includes twelve low-pressure mercury UV lamps with a total power consumption of 658 watts. Lamps rated at 100, 75, and 18 watts produced UV doses of 9.314, 7.737, and 4.643 milliwatt-seconds per square centimeter, respectively, resulting in a significant microbiological reduction of Escherichia coli and most pathogens by 90% (1-log or D₉₀). At a water flow rate of 32 liters per second, the UV radiation achieved a 99% reduction (2-log or D₉₉) in microbial contamination. Field implementation was conducted at a large surface water village supply system in Moo 2, Phon Khrok Sub-district, Tha Tum District, Surin Province, where the system was installed at the main distribution pipe connected to the elevated water tank. The results confirmed effective disinfection; however, pathogen contamination was still detected at the endpoints due to pipeline recontamination. To address this, drinking water filtration systems developed by the Department of Science Service were installed to ensure compliance with the potable water quality standards of the Department of Health. This research is scalable for addressing village tap water quality nationwide and aligns with the 20-Year Master Plan for Water Resource Management (2018–2037), which mandates that every village have access to clean water for consumption and household use that meets quality standards.