The railway brake system usually uses compressed air brake system which uses high-pressure air to press the brake shoe on the surface of the wheel to reduce the speed of the train. Repeated friction generates heat at the contact surface, increasing thermal stress on the cast iron brake shoe. The purpose of this study is to investigate the thermal stress on a prototype of cast iron brake shoe using the finite element method compare the analytical results to the actual brake shoe and redesign a brake shoe prototype to reduce thermal stress. Based on the results of the thermal stress study using the finite element method, it has shown that the location of the thermal stress on the prototype brake shoe according to the location of the crack on the real brake shoe. The brake shoe's design which includes single notch in the center of brake shoe which is can help to reduce thermal stress. The results from this study should be validated with the results from the field test to evaluate both of thermal distribution and braking efficiency in term of braking distances as well.
ระบบเบรกของรถไฟนิยมใช้ระบบเบรกแบบลมอัด โดยใช้อากาศแรงดันสูงกดแท่งห้ามล้อไปสัมผัสกับผิวของล้อเพื่อลดความเร็วของรถไฟ เมื่อเกิดการเสียดสีกันซ้ำ ๆ จึงเกิดความร้อนขึ้นบริเวณผิวสัมผัส ทำให้เกิดความเค้นสะสมเนื่องจากความร้อนบนแท่งห้ามล้อวัสดุเหล็กหล่อ งานวิจัยนี้จึงมีวัตถุประสงค์เพื่อศึกษาความเค้นเนื่องจากความร้อน (Thermal stress) บนแท่งห้ามล้อวัสดุเหล็กหล่อรูปแบบต้นแบบด้วยระเบียบวิธีไฟไนต์เอลิเมนต์เพื่อเปรียบเทียบผลการวิเคราะห์ที่ได้กับแท่งห้ามล้อชิ้นงานจริง และออกแบบแท่งห้ามล้อวัสดุเหล็กหล่อในรูปแบบใหม่เพื่อลดความเค้นเนื่องจากความร้อนที่เกิดขึ้น
คณะวิศวกรรมศาสตร์
The integration of intelligent robotic systems into human-centric environments, such as laboratories, hospitals, and educational institutions, has become increasingly important due to the growing demand for accessible and context-aware assistants. However, current solutions often lack scalability—for instance, relying on specialized personnel to repeatedly answer the same questions as administrators for specific departments—and adaptability to dynamic environments that require real-time situational responses. This study introduces a novel framework for an interactive robotic assistant (Beckerle et al. , 2017) designed to assist during laboratory tours and mitigate the challenges posed by limited human resources in providing comprehensive information to visitors. The proposed system operates through multiple modes, including standby mode and recognition mode, to ensure seamless interaction and adaptability in various contexts. In standby mode, the robot signals readiness with a smiling face animation while patrolling predefined paths or conserving energy when stationary. Advanced obstacle detection ensures safe navigation in dynamic environments. Recognition mode activates through gestures or wake words, using advanced computer vision and real-time speech recognition to identify users. Facial recognition further classifies individuals as known or unknown, providing personalized greetings or context-specific guidance to enhance user engagement. The proposed robot and its 3D design are shown in Figure 1. In interactive mode, the system integrates advanced technologies, including advanced speech recognition (ASR Whisper), natural language processing (NLP), and a large language model Ollama 3.2 (LLM Predictor, 2025), to provide a user-friendly, context-aware, and adaptable experience. Motivated by the need to engage students and promote interest in the RAI department, which receives over 1,000 visitors annually, it addresses accessibility gaps where human staff may be unavailable. With wake word detection, face and gesture recognition, and LiDAR-based obstacle detection, the robot ensures seamless communication in English, alongside safe and efficient navigation. The Retrieval-Augmented Generation (RAG) human interaction system communicates with the mobile robot, built on ROS1 Noetic, using the MQTT protocol over Ethernet. It publishes navigation goals to the move_base module in ROS, which autonomously handles navigation and obstacle avoidance. A diagram is explained in Figure 2. The framework includes a robust back-end architecture utilizing a combination of MongoDB for information storage and retrieval and a RAG mechanism (Thüs et al., 2024) to process program curriculum information in the form of PDFs. This ensures that the robot provides accurate and contextually relevant answers to user queries. Furthermore, the inclusion of smiling face animations and text-to-speech (TTS BotNoi) enhanced user engagement metrics were derived through a combination of observational studies and surveys, which highlighted significant improvements in user satisfaction and accessibility. This paper also discusses capability to operate in dynamic environments and human-centric spaces. For example, handling interruptions while navigating during a mission. The modular design allows for easy integration of additional features, such as gesture recognition and hardware upgrades, ensuring long-term scalability. However, limitations such as the need for high initial setup costs and dependency on specific hardware configurations are acknowledged. Future work will focus on enhancing the system’s adaptability to diverse languages, expanding its use cases, and exploring collaborative interactions between multiple robots. In conclusion, the proposed interactive robotic assistant represents a significant step forward in bridging the gap between human needs and technological advancements. By combining cutting-edge AI technologies with practical hardware solutions, this work offers a scalable, efficient, and user-friendly system that enhances accessibility and user engagement in human-centric spaces.
คณะอุตสาหกรรมอาหาร
Coffee is a critical agricultural commodity to be used to produce a premium beverage to serve people worldwide. Coffee microbiome turned to be an essential tool to improve the bean quality through the natural fermentation. Therefore, understanding the microbial diversities could create the final product's better quality. This study investigated the natural microbial consortium during the wet process fermentation of coffee onsite in Thailand to characterize the microorganisms involved in correlation toward the biochemical characteristics and metabolic attributes. Roasting is another important step in developing the complex flavor/ aroma that make coffee to be enjoyable. During the roasting process, the beans undergo many complex and alternatively change in the physicochemical properties from the gained substances in the fermentation process. The changing in the formation of the substances responsible for the sensory qualities, physicochemical/ aroma attributes as well as the health benefits of the final product. Using the starter culture could also develop the distinguished characteristics of coffee (Research collaboration with Van Hart company)
คณะบริหารธุรกิจ
CO Breathalyzer with Voice Response is the device to measured the level of CO residual in a person's lung who consume tobacco. Measuring residual CO in human breath can identify the tobacco addiction level instead of measuring nicotine in blood.