Valaya Alongkorn Rajabhat University

This study proposes an innovative discontinuous Space Vector Pulse Width Modulation (SVPWM) technique integrated with a DQ-based current control scheme for a three-level T-type (3L-T-Type) inverter running in grid-connected mode. The discontinuous modulation technique employs the Nearest Three Vectors (NTVs) from the space vector diagram to provide appropriate switching signals, which substantially decreases the commutation of the Controllable Power Switches (CPSs), thus reducing switching losses. To enhance the output power quality prior to grid injection, a transformation from standard DQ current control to active and reactive Power Control (PQ) is implemented. The proposed method allows for separate control of the d-axis and q-axis components while keeping them in sync with the grid voltage. A mathematical model was developed to compute the stay time of each switching state across different regions and sectors, facilitating the generation of discontinuous modulation waves for each phase leg. The simulation results in MATLAB/Simulink demonstrate improved performance with a 33% reduction in switching commutations, a Total Harmonic Distortion (THD) of 4.67% for the current, proper alignment with the grid voltage at the main frequency of 50 Hz, and effective balancing of the DC-link voltage. These findings confirm the proposed controller's efficacy and its appropriateness for high-performance grid-connected applications, including renewable energy integration and electric vehicle infrastructure.

This study compares traditional manual and modern mechanical methods of producing puffed rice in Thailand, in order to improve the efficiency and quality of the process and increase its scalability. Thailand is one of the world’s leading rice producers, but the industry faces challenges due to limited mechanization, high labor intensity, and underdeveloped value-added applications. Experimental trials were conducted using selected rice varieties with different grain sizes and amylose contents. The findings showed that rice with higher length-to-width ratios and amylose contents had better results. The mechanical method exhibited a higher average expansion ratio (12.50) than the manual one (11.80), and doubled production capacity (400 kg/day versus 200 kg/day). Furthermore, the mechanical method achieved a production rate of 55.81 kg/h, a lower loss rate of 7.67%, and batch time reduced to 10 min, with no significant taste quality differences. Using salt soaking and maintaining an optimal moisture content of 10%-13% improved puffing consistency. This research introduces a novel, semi-automatic, double-head puffing prototype that integrates electro-pneumatic actuation and a Programmable Logic Controller (PLC), enabling synchronized, continuous puffing operations. This increases automation and labor efficiency beyond the capabilities of conventional single-head machines. Although traditional methods are appropriate for small-scale use, the mechanical system offers significant advantages in consistency, and ergonomics.

Erythemal ultraviolet (EUV) irradiance, with a wavelength range of 280–400 nm, is associated with both health risks and physiological benefits. While moderate EUV exposure stimulates vitamin D synthesis—essential for bone health and immune function—excessive exposure can cause skin damage, ocular complications, and increased risk of skin cancer, highlighting the need for accurate UV monitoring. However, ground-based measurements remain limited due to the high cost of instrumentation. This study introduces a semi-empirical model for estimating hourly EUV irradiance in Thailand using meteorological and satellite data. The model was developed using cloud index, visibility, total column ozone, and the cosine of the solar zenith angle across four stations: Chiang Mai, Ubon Ratchathani, Nakhon Pathom, and Songkhla. The baseline model, constructed using data from 2016 to 2019, achieved a mean bias difference (MBD) of 3.57%, a root mean square difference (RMSD) of 21.80%, and an R² of 0.81. However, its performance declined in areas with high aerosol loading and low visibility, particularly in Chiang Mai, where seasonal biomass burning is prevalent. To improve accuracy, a modified model was developed by incorporating aerosol optical depth (AOD) at stations where such data were available. The enhanced model yielded an MBD of 6.18%, an RMSD of 15.16%, and an R² of 0.93. These results highlight the critical role of aerosols in UV attenuation and demonstrate the model’s potential for scalable, cost-effective applications in UV risk assessment, especially in regions lacking high-resolution ground monitoring infrastructure.

การวิจัยนี้มีวัตถุประสงค์เพื่อศึกษาทัศนคติและการมีส่วนร่วมในการพัฒนาการท่องเที่ยวเชิงวัฒนธรรม ตำบลโคกสูง อำเภอโคกสูง จังหวัดสระแก้ว โดยวิธีวิจัยเชิงปริมาณเก็บรวบรวมข้อมูลโดยใช้แบบสอบถาม ลักษณะแบบสอบถามเป็นแบบตรวจสอบรายการ (Check list) ใช้วิธีหาค่าร้อยละ และเป็นแบบมาตราส่วนประมาณค่า (Rating Scale) ใช้วิธีหาค่าเฉลี่ย () และค่าส่วนเบี่ยงเบนมาตรฐาน การสุ่มแบบตามสะดวกจากประชาชนภายในชุมชนตำบลโคกสูงทั้งหมด 11 หมู่บ้านและผู้ที่ทำงานในตำบลโคกสูงแต่พำนักอาศัยนอกพื้นที่ตำบล จำนวน 375 คน พบว่า ทัศนคติที่มีต่อการพัฒนาการท่องเที่ยวเชิงวัฒนธรรมทุกด้าน ได้แก่ ด้านสังคม ด้านเศรษฐกิจ ด้านวัฒนธรรม และด้านสิ่งแวดล้อมอยู่ในระดับมาก ขณะเดียวกันผลการมีส่วนร่วมในการจัดการท่องเที่ยวเชิงวัฒนธรรม พบว่า ด้านการมีส่วนร่วมในการปฏิบัติอยู่ในระดับมาก ขณะที่ด้านการมีส่วนร่วมในการรับผลประโยชน์ ด้านการมีส่วนร่วมในการติดตามประเมินผล และด้านการมีส่วนร่วมในการตัดสินใจอยู่ในระดับปานกลาง ทั้งนี้ผลการศึกษาสามารถใช้เป็นข้อมูลสำหรับหน่วยงานท้องถิ่นในการวางแผนพัฒนาแหล่งท่องเที่ยวให้เหมาะสมกับบริบทของชุมชนเพื่อความยั่งยืนของการบริหารจัดการท่องเที่ยวของตำบลโคกสูง อีกทั้งสถานศึกษาในท้องถิ่นสามารถนำข้อมูลมาใช้วางแผนการฝึกอบรม พัฒนา หรือส่งเสริมศักยภาพการมีส่วนร่วมของคนในชุมชน สร้างความตระหนักถึงคุณค่าของการมีส่วนร่วมในการพัฒนาท้องถิ่นเพื่อให้วัฒนธรรมท้องถิ่นยังคงอยู่ต่อไป

Pesticide exposure is a significant occupational hazard among cassava farmers, raising various health and environmental concerns. Health literacy plays a crucial role in enabling farmers to understand and implement effective pesticide protective behaviors. This cross-sectional study examined health literacy and factors influencing pesticide protective behavior among cassava farmers. The participants were 399 cassava farmers registered as growers in one province in eastern Thailand, aged 20-65. They had at least one year of experience using chemical pesticides in cassava cultivation. Data was collected using structured questionnaires from December 2024 to January 2025. Instruments were comprised of Individual and Health Factors, Pesticide Usage Factors, Health Literacy on Pesticide Use, and Pesticide Protective Behaviors Questionnaire. Data analysis was conducted through descriptive statistics and multiple logistic regression techniques. The findings indicated that the majority of cassava farmers possessed a moderate level of overall health literacy (48.1%) and exhibited pesticide protective behaviors (57.6%). A statistically significant positive relationship was observed between health literacy and pesticide protective behavior. Factors significantly associated with pesticide protective behaviors among cassava farmers included health literacy, age, education level, monthly income, allergic reactions from pesticide use, and duration of pesticide use, with health literacy being the strongest predictor. This study demonstrates that health literacy is crucial for enhancing pesticide protective behaviors. Nursing interventions should focus on educational strategies that enhance health literacy to promote safer pesticide practices, as well as the need for public health policies that support health literacy in agricultural safety programs, to safeguard the health of farming communities.

Background and aims: With the continuous development and change of the national actual situation and educational policies, to adapt to the development of the era and the changing needs of students, improve the teaching quality and effect, and promote the professional development of teachers, establishing and improving the education curriculum system for middle school music teachers is an urgent task for cultivating middle school music teachers. The objectives of this research were as follows: 1) To study the background information focusing on course components, existing problems, and relevant educational theories for developing the Music Teaching Practice in Middle Schools Course based on Team-based learning (TBL) combined with a peer assessment method. 2) To develop the Music Teaching Practice in Middle Schools Course based on Team-based learning (TBL) combined with the peer assessment method. Materials and methods: In Phase 1, the first step is to query relevant documents and obtain background information through content analysis; The second step is to use interview forms to interview 5 teachers and 15 students, and the data on existing problems is collected by the interview process and the voice record tool. The content analysis through the thematic coding analysis method is used for analyzing and summarizing collected data. In Phase 2, the researchers drafted course content, and 5 experts evaluated the course composition draft. After gathering the data, the data were analyzed for appropriateness. Results: The components of the Music Teaching Practice in Middle Schools course, based on Team-based learning (TBL) combined with the peer assessment method, were: 1) Course principles, 2) Course objectives, 3) Course contents, 4) Course instructional strategy, 5) Course materials and resources, 6) Course evaluation methods. And these components had a good quality of appropriateness. Conclusion: Through the analysis of background information, it is necessary to improve and develop a Music Teaching Practice in Middle Schools Course model that conforms to the actual music teaching in middle schools. The course document evaluation by experts shows that the Music Teaching Practice in Middle Schools Course, based on Team-based learning (TBL) combined with the peer assessment method developed in this study at a high level is satisfactory.

Background and Aim: Based on relevant policies and literature, such as higher education planning at home and abroad, policies of the Chinese Ministry of Education, educational concepts, cognitive learning theories, project-based learning methods, teaching strategies, and teaching evaluations, researchers interviewed teachers and students on the current foundation of the programming design course. This research and development aimed 1 to study the background information focusing on the course components of the foundation of programming design course to enhance students’ computational thinking ability. 2) To develop the foundation of a programming design course based on Cognitive learning theory, combined with Project-based learning to enhance students’ computational thinking ability. 3) To determine the effectiveness of implementing the foundation of programming design course based on Cognitive learning theory combined with Project-based learning. Materials and Methods: The sample of this research was 30 first-year students (1 class) majoring in Network Engineering class 1, in the academic year 2024-2025 of Zhoukou Normal University, Henan Province, China. They are derived from using a cluster random sampling method. The experimental design adopted in this research was a group posttest-only design. The research instruments from each Phase of the study were as follows: Phase I: Interview forms for teachers and students on course-related questions. Phase II: 1) Foundation of programming design course based on Cognitive learning theory combined with Project-Based Learning. 2) 12 lesson plans for the foundation of the programming design course. 3) Evaluation form of computational thinking skills. 4) Learning achievement test. 5)Satisfaction questionnaire. The data were analyzed by using mean, standard deviation, and the one-sample t-test. Results: The results of this research were as follows: 1) The researcher reviewed the related documents about the Foundation of Programming Design Course and interviewed the 4 teachers and 30 students about problems of the Foundation of Programming Design Course, and the information gathered was used to develop the course. 2) The course development in six aspects: Course principles, Course objectives, Course content, Course instructional strategies, Course media and resources, and Course evaluation. 3) After implementing through Foundation of Programming Design Course based on Cognitive Learning Theory combined with Project-Based Learning, students’ computational thinking ability (Knowledge) was higher than the determined criterion of 70% at a significance level of 0.05; students’ computational thinking ability (Skills) was higher than the determined criterion of 70% at a significance level of .05. 4) The mean scores of students’ satisfaction after implementing the Foundation of Programming Design Course based on Cognitive Learning Theory combined with Project-Based Learning was 4.838 from a possible full mark of 5, and the standard deviation was 0.176, which was statistically higher than the criterion of 70% at the .05 level of statistical significance. Conclusion: This research confirms the effectiveness of the teaching model based on Cognitive learning theory combined with Project-Based Learning to enhance students' computational thinking ability.

This research aims to analyze the land use and land cover change (LULCC) in Yang Talat District, Kalasin Province, using Sentinel-2 satellite imagery from 2019 to 2024. A supervised classification technique, specifically the Spectral Angle Mapper (SAM) algorithm, was employed to classify land use into six main categories: built-up areas, forest, water bodies, paddy fields, shrimp farms, and field crops. The accuracy assessment of the classified maps demonstrated high reliability, with an overall accuracy of 88.33% for 2019 and 89.00% for 2024. The change analysis revealed a significant increase in field crops (+39.82%) and shrimp farms (+35.23%), while forest area decreased by -9.60% and paddy fields by -1.35%. The transition matrix analysis confirmed that the most notable changes were the conversion of forest and paddy fields into field crops and built-up areas. These findings highlight the dynamic nature of LULCC in the study area, influenced by socioeconomic factors. The results provide valuable data for local policymakers to develop sustainable land management strategies

This research aimed to evaluate the potential of tobacco extract for controlling stable flies (Stomoxys calcitrans L.) in beef cattle. The study was divided into three experiments: 1) determination of nicotine concentration in tobacco extract using different fermentation times, 2) laboratory assessment of tobacco extract efficacy against stable flies, and 3) field evaluation of tobacco extract efficacy against stable flies. Results showed that fermenting tobacco with 95% ethanol for 48 hours yielded the highest nicotine content at 46.71 μg/mg, which was significantly different (P<0.001) compared to other fermentation periods. Laboratory studies revealed that the efficacy of tobacco extract in eliminating stable flies increased with concentration and exposure time. The 20% tobacco extract showed maximum efficacy with mortality rates of 98.33% at 24 hours and 100% at 48 hours, while 3% tobacco extract achieved 95% mortality of stable flies at 72 hours. In field trials, 3% tobacco extract demonstrated significantly better control of stable flies compared to the control treatment (distilled water) (P<0.001), but was less effective than 35% cypermethrin. The efficacy of tobacco extract decreased after 96 hours post-application, corresponding with increased fly-repelling behaviors in cattle, including tail flicking, skin twitching, foot stamping, and head swinging. Results from this study indicate that tobacco extract has potential as an alternative to synthetic chemicals for controlling stable flies in beef cattle, which helps reduce chemical use and is environmentally friendly.