This research aimed to isolate and culture four strains of lactic acid bacteria (LAB) isolated from fermented foods. The antimicrobial activity of the lactic acid bacteria was studied using the agar spot method and the antibiotic resistance properties of the lactic acid bacteria were studied using the agar overlay diffusion method. The results showed that each strain of lactic acid bacteria had different levels of antimicrobial activity and antibiotic resistance, which are safety properties of probiotic microorganisms.
จุลินทรีย์โพรไบโอติก (Probiotic) หมายความว่า จุลินทรีย์ที่มีชีวิต ซึ่งเมื่อร่างกายได้รับในปริมาณที่เพียงพอจะทำให้เกิดผลที่เป็นประโยชน์ต่อสุขภาพ อาหารที่มีการใช้จุลินทรีย์โพรไบโอติกต้องได้รับอนุญาตจากสำนักงานคณะกรรมการ อาหารและยา และ ต้องใช้จุลินทรีย์ตามที่กำหนดไว้ ดังนั้นการวิจัยนี้จึงนำเชื้อแบคทีเรียแลคติกที่แยกได้จากอาหารหมัก 4 สายพันธุ์ มาศึกษาฤทธิ์การต้านเชื้อแบคทีเรียก่อโรคในอาหาร และ ศึกษาสมบัติการดื้อยาของเชื้อแบคทีเรียแลคติก
คณะวิศวกรรมศาสตร์
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.
คณะครุศาสตร์อุตสาหกรรมและเทคโนโลยี
This project presents the development of a single-frequency GPS-based total electron content measurement tool. It applies theories related to total electron content in the ionospheric layer and the measurement of total electron content using GPS time delay to design the single-frequency GPS total electron content measurement tool. The tool consists of an antenna, a single-frequency GPS satellite receiver, a data processing unit for evaluating and calculating total electron content, and a display unit for showing total electron content data. The performance of the single-frequency GPS total electron content measurement tool is tested by comparing it with total electron content data obtained from the International Reference Ionosphere (IRI) model, which is a global reference model for electron content. The tool is also put to practical use. The results of the comparison and practical applications conclude that the single-frequency GPS-based total electron content measurement tool can be effectively utilized, with the difference from the IRI model being 50 TECU
คณะวิศวกรรมศาสตร์
This research project focuses on the design and development of a Manual Control Robot using Load Cell technology to enhance precision and reduce the time required for robot control. The use of automation robots in industries still presents challenges due to the complexity of programming and control. Therefore, developing a manual control system that responds to force input in all directions can significantly improve the efficiency of robots, making them more suitable for tasks requiring precise and intricate control. The study integrates Load Cell sensors, an HX711 amplifier circuit, and an Arduino UNO R3 to develop a control module that translates user-applied forces into commands for an RV-7FRL-D industrial robotic arm. Additionally, MATLAB is utilized for processing Load Cell data to analyze and optimize the robot’s movement accuracy. The results demonstrate that the developed system effectively reduces robot setup time while simplifying and improving control flexibility. This project represents a crucial step in enhancing the capabilities of industrial robots, allowing for seamless human-robot interaction through a manual control system that directly responds to user-applied forces.