Rattanakosin Journal of Science and Technology

Greenhouse Effect Solar Dryer for Banana

Yutthana Sriudom — 2025-12-30

The study aims to investigate the impact of varying wind speeds and to study the effects of wind speed, inlet, and outlet locations on the moisture reduction and drying rate of bananas using solar energy. The initial moisture content of the bananas is approximately 230 percent dry basis, and they are dried until the final moisture content reaches approximately 28 percent dry basis. The dimensions of the greenhouse are set at 1.25 meters in width, 1.90 meters in length, and 0.80 meters in height, utilizing translucent polycarbonate sheets as the primary construction material. Ventilation is facilitated by a 6-inch fan installed within the structure. The air flow rate is divided into 2 levels: 1.0 m/s (Level 1) and 1.5 m/s (Level 2). Results revealed that when the air inlet was positioned at the bottom with the air outlet open, and an average wind speed of 1.5 meters per second was maintained, the highest average weight loss rate was achieved. Specifically, the average weight loss rate per hour reached 0.157 kilograms.

Detection of Attack Behaviors in IoT Networks Using Temporal Convolutional Networks (TCN)

Praveen Maiget — 2025-12-30

This research aims to (1) develop a framework for detecting attack behaviors in IoT networks using the Temporal Convolutional Networks (TCN) model and (2) evaluate the performance of the TCN model by comparing it with RNN, LSTM, GRU, and DNN models. The experiment was conducted over a 12-week period using Python as the primary programming language. A synthetic dataset was utilized, simulating Denial-of-Service (DoS) and Man-in-the-Middle (MITM) cyberattacks. The research process involved data transformation and preprocessing, followed by training the models using TensorFlow/Keras on Google Colab. The experimental results revealed that the TCN model achieved a high recall score (0.9986), indicating its ability to detect nearly all attack events. However, its accuracy (≈0.50) and precision (0.4978) were low, leading to a high false positive rate. Additionally, the loss values exhibited significant fluctuations, reflecting the model's instability in learning the data effectively. In comparison, the RNN model provided balanced results, LSTM and GRU demonstrated high efficiency in handling complex data, and DNN achieved the highest accuracy. These findings suggest that while the
TCN model performs well in detecting attack behaviors in terms of recall, it requires further improvements to enhance precision and accuracy. To address these issues, improving dataset quality, applying hyperparameter tuning, implementing regularization techniques to reduce overfitting, and testing the framework with real-world datasets are recommended. These improvements will contribute to a more reliable and effective security system for IoT networks.

On Finding Integer Solutions to Homogeneous Ternary Quadratic Diophantine Equation

N. Thiruniraiselvi — 2025-12-30

The theoretical importance of polynomial equations of second degree in three unknowns with integral coefficients is great as they are closely connected with many problems of number theory. Specifically, the second degree polynomial equations with three unknowns in connection with geometrical figures occupy a pivotal role in the region of mathematics. The successful completion of exhibiting all integers satisfying the requirements set forth in the problem add to further progress of Number Theory as they offer good applications in the field of Graph theory, Modular theory, Coding and Cryptography, Engineering, Music and so on. Integers have repeatedly played a crucial role in the evolution of the Natural Sciences. The theory of integers provides answers to real world problems. Objectives: The objective of this research paper is to obtain varieties of integer solutions to homogeneous ternary quadratic Diophantine equation represented by the proposed equation . Geometrically, the considered polynomial equations of degree two with three unknowns represents cone. Methods: Various choices of integer solutions are secure from beginning to end employing linear modifications and used to simplify expressions. Patterns of solutions in integers are obtained by reducing the given polynomial equation to the equation which is solvable through employing suitable transformations and applying the factorization method. Findings: Six distinct transformations are applied to obtain choices of integral solutions for the considered second degree equation having three unknowns. Novelty: The equation in title has been reduced to either solvable ternary quadratic equation or a system of simultaneous equations through employing suitable transformations. Many lattice points satisfying the given cone are obtained through analytical process by means of substitution strategy and method of factorization.

Hot Air Drying Machine Set with Raspberry Pi

Yutti Chatwaranon — 2025-12-30

This research is the development of hot air herbal dryer model from the experiment using 3 types of hot air herbal dryers: (i). Factory hot air dryer (ii). Improved hot air dryer and (iii). Reverse hot air dryer. The two herbs, turmeric and lemongrass, were dried to 350 grams, divided into 4 layers, 87.5 grams each, at a drying temperature of 70 degrees Celsius, and for 540 minutes. In the weight test after drying herbs, it was found that the hot air herbal dryer model 3 could dry all layers of herbs thoroughly because the weight measurement of herbs in each layer was the closest. Lemongrass weighed a total of 49 grams and turmeric weighed 55 grams, which were less than the hot air herbal dryer models 1 and 2. The drying of herbs to measure the final moisture after drying took 9 hours, while the herbal dryer model 3 took 7 hours, which was less than the models 1 and 2, which had a difference of 2 hours. After drying, And the moisture content of the herbs that were baked, Type 1 and Type 2, were different from Type 3 in both samples. Turmeric had a moisture content of 16.14% when comparing Type 1 and Type 2 to Type 3, and lemongrass had a moisture content of 13.9% when comparing the same. In conclusion, Type 1 and Type 2, when compared to Type 3, had a baking time difference of 2 hours, and the moisture content when comparing lemongrass, where Type 3 was able to repel moisture better than Type 1 and Type 2.

Obstacle Detection Device to Enhance the Quality of Life for the Visually Impaired

Khanittha Wannakam — 2025-12-30

This paper presents the development of an obstacle detection device aimed at enhancing the quality of life for visually impaired individuals. The device was designed and constructed to detect obstacles in four directions, left, right, front, and back, incorporating an auditory alert system that increases in frequency as the user approaches an obstacle. Additionally, a fall detection system was integrated, enabling caregivers to automatically receive notifications via Line Notify in case of a fall or accident. Experimental evaluations demonstrated that the device exhibits high accuracy in obstacle detection across all directions and effectively identifies objects of varying colors and sizes. The sensors functioned reliably at both short and long distances. The fall detection system was tested by simulating falls in four directions: forward, backward, left, and right, with 30 trials per direction. The system achieved an accuracy rate of 95.83%, with an error margin of 4.17%, successfully sending notifications in every instance of a detected fall. A user satisfaction survey conducted with 10 visually impaired participants indicated an average satisfaction level categorized as "highest satisfaction." These findings highlight the potential of this device to significantly improve the safety and mobility of visually impaired individuals, offering a practical and effective assistive solution.

Static Analysis of Deep Water Hemi-Ellipsoidal Shells by Higher-Order Shear Deformation Theory

Pit Nantachaisi — 2025-12-30

This paper presents the static response of deep water hemi-ellipsoidal shells. The shell geometry is determined using differential geometry, while the displacement field is derived based on higher-order shear deformation theory. The energy functional of the shell system can be formulated via the principle of virtual work. The numerical results of the static deformed configuration of the hemi-ellipsoidal shells are obtained by the finite element method employing nine-node quadrilateral isoparametric elements. Specifically, this study examines the effects of external hydrostatic pressure on hemi-ellipsoidal shells under various height-to-base radius ratios and support conditions. The results indicate that the displacement response depends on the height-to-base radius ratios of the hemi-ellipsoidal shells. The normal displacement of the hemi-spherical shells is lower than the hemi-oblate and prolate shells at the apex and support, respectively.

Waste Situation and Geographic Information System Technology: A Case Study of Rajamangala University of Technology Rattanakosin, Salaya Campus

Samittanan Kanjanjongkol — 2025-12-30

waste, 3.48%. Many outdoor bin placement areas are not suitable due to being close to water bodies and office buildings, as well as incomplete waste separation management and the use of the wrong types of bins. The management approach should start with serious waste separation, with the discarders sorting them and using bins according to the type of waste. The analysis of the area for outdoor waste bin, which involved overlaying Union data, helped determine the appropriate trash bin placement points for up to 72 locations from 0.0045 km².

An Analysis of Energy and Carbon Emission in Coal-Fired Boiler of Beverage Industry

Kritsana Asuwan — 2025-12-30

The aim of this work is to assess the coal-fired boiler along with the combination of the energetic, environment and economic point of view at 25%, 50%, 75% and 100% of load boiler. The capacity of coal-fired boiler is 16 Ton/h, 8 bar (saturated vapor) with an economizer. The operation was conducted to collect and record data throughout the year. The results shown that energy in coal, energy in steam and energetic efficiency were increased with increase in load boiler. Eighty percentage of operating time (1 year), 50% and 75% in load boiler emitted the CO₂ emission into the atmosphere by approximately 28,710.53 tCO₂eq/y and the environmental cost value is 14,770,416.01 THB/y. Considering the operating boiler’s load throughout the year, the CO₂ emission into the atmosphere and the environmental cost value were 35,007.23 tCO₂eq/y and 18,009,819.40 THB/y, respectively.