SAU JOURNAL OF SCIENCE & TECHNOLOGY

Design and Development of Solar Panel Current-Voltage Characterization Instrument Using Arduino Nano Board

Chokchai Chuenwattanapraniti, Montana Rungsiyopas — Sat, 23 Dec 2023 00:00:00 +0700

It is necessary to measure the generation performance of solar panels installed on site since the yield of electricity produced by solar panels depends on many environmental factors. Therefore, this paper presents the design and development of a simple, small, and low-cost instrument for measuring the electrical characteristics of solar panels. The proposed instrument is equipped with the Arduino microcontroller board responsible for controlling and signal processing in conjunction with the capacitor charging circuit that sweeps the panel output voltage. The instrument’s display on the Human Machine Interface (HMI) screen has 2 formats including a current-voltage graph and a table showing electrical parameters for the diagnosis purpose. The 4% of maximum discrepancy between the test results carried out from the proposed instrument and a commercial device under different solar irradiance and the partial shading conditions confirmed that the proposed instrument is comparable with the commercial one.

Risk Perception and Hazard Prevention Behaviors of Garbage Collector of the Sathon District

patpischar tongjeeraanunt, Nipattra Haritavorn, Laksana Loakiat — Sat, 23 Dec 2023 00:00:00 +0700

The objectives of this cross-sectional descriptive research were to study the risk perception and hazard prevention behaviors of garbage collectors in the Sathon district office. The data were collected among 130 garbage collectors who had worked in this office at least 6 months by using a questionnaire and interviewed the executive officers related to occupational safety management. Descriptive statistics used for analysis were frequency, percentage, mean, and standard deviation, while inferential statistics were Chi-square and Pearson’s product-moment correlation coefficient at the statistical significance level of 0.05. The result showed that garbage collectors had a risk perception at a good level of only 38.5%, but the overall occupational hazard prevention behavior was at a good level of 53.1%. Personal factors, health and safety factors that had statistically significant correlation with occupational hazard prevention behaviors, were work cycle (p=0.042), working time in the day (p<0.001), and work-related accidents/illnesses (p<0.001). There was a moderate positive correlation between risk perception and occupational hazard prevention behavior (r=0.498, p-value<0.01). In addition, the interview results revealed that the Sathon district office had administrative control for occupational hazard prevention such as organizational safety policy, preventive training program, and supported personal protective equipment. Therefore, the Sathon district office should enhance the garbage collectors’ occupational hazard prevention behaviors at a good level continually by setting compliance with rules or regulations about occupational hazard prevention behaviors, such as establishing a clear penalty and providing information about correct occupational practices which will help workers collecting waste more efficient and safer.

Design and Build of Biomass Machine for Small Engines

Wasawat Saowadee; Anotai Suksangpanomrung, Chawin Chantharasenawong — Sat, 23 Dec 2023 00:00:00 +0700

Abstract Biomass machine are those causing incomplete combustion with the limited amount of oxygen used in combustion of 30–40% less than complete combustion. Biomass gas derived from the gasification combustion process contains such the main components as carbon monoxide (CO), hydrogen (H₂), methane (CH₄), carbon dioxide (CO₂), and other combustible gases. This research aims to study the design of a biomass generator for the military water supply unit’s engine when going out in the field or assisting various incidents by using biomass as its fuel. Initially, experiments were conducted to determine the biomass gas factors in each operating condition of the engine. Several parameters were adjusted, namely speed of biomass entering the engine, temperature of biomass in the combustion chamber, and the ratio of ingredients between biomass gas and air. Subsequently, the use of biomass fuel was compared with benzene gasohol 95 benzene. The results indicated that the average rate of using the gasohol 95 in running the engine for one hour used an amount of gasohol 95 of 722.67 cc, equivalent to 15.72 Thai Baht. On the contrary, changing to biomass fuel to run the engine for one hour is equal to using 975.50 grams of charcoal of Krathin-Narong trees, all of which are worth 9.75 Thai Baht. The prices of both types of fuel are referred to the one of gasohol 95 on September 9, 2020, at 21.75 baht per liter [9], and another of Krathin-Narong Charcoal at 10 Thai Baht per kilogram. Operating an engine using biomass fuel together with gasohol 95 could reduce benzene consumption by 7.86 Thai Baht per hour. In return for the cost of constructing a traditional biomass generator, it takes approximately 80 days for operation to become cost-effective.

Mathematical Model of Solidification of Hydrated Salts with a Longitudinal Fin of Rectangular Profile

Pheerawat Minta, Worachest Pirompugd — Sat, 23 Dec 2023 00:00:00 +0700

Salt hydrates are inorganic phase change materials (PCMs) that can absorb and release heat energy during the phase change process. There are good properties for many applications, such as high latent heat, non-flammable, good energy storage capacity and expensive. Salt Hydrates are used for storage applications such as greenhouses and PCMs energy storage. In this paper, a mathematical model of solidification of a PCMs called hydrated salt is developed and analyzed. The conditions are that the wall temperature is 25 °C, fin length is 0.05 m., fin width is 0.01 m. PCMs storage heights are 7 sizes, 0.01 – 0.07 m. in increments of 1 cm. For a height of 0.01 m, the total time of solidification of PCMs is minimum. For at a height of 0.05 – 0.07 meters, it takes the same time for solidification and takes the most time. From the mathematical model it is found that the time, wall temperature, and fin size affect the distance of PCMs solidification.

MACHINE LEARNING BASED PREDICTION ANALYSIS FOR THE SERVICE LEVEL AGREEMENT: A CASE STUDY OF DHANARAK ASSET DEVELOPMENT CO., LTD.

Panisara Phetkhong, Chutima Beokhaimook — Sat, 23 Dec 2023 00:00:00 +0700

The purpose of this research is to analyze and compare the efficiency of the prediction models for the success of the service level agreement of Dhanarak Asset Development Co., Ltd by using building management system data. The researcher has used five techniques, including support vector machines, decision tree, k-nearest neighbor, perceptron and Adaboost algorithms to create 5 classification models and compare the performance of success prediction among those 5 different models. The results showed that Adaboot Algorithm gave the highest accuracy of 69%, support vector machine and decision tree equally yielded 67% accuracy, while the nearest neighbor and perceptron provided 66% and the 56% accuracies, respectively. Although the evaluating results of the five forecasting models gave a not very high accuracies, the forecasting models can actually be used in business by considering other factors, such as, risk analysis in preparing spare equipment for repairs, analysis of building deterioration, preparation of various resources in order to determine work plans to be successful according to service level agreements.

Risk Management in the Electrical System Installations for Construction of High-Rise Buildings

Thadapong Khowploum, Sakchai Rakkarn, Podchanee Sriwichian — Sat, 23 Dec 2023 00:00:00 +0700

This research aims to efficiently analyze and manage risks in order to minimize accidents in high-rise installation of electrical systems by statistical number data for the year 2017-2021, more than 101 accidents occurred from accumulated operations, an average of 20.2 people per year or 10.1% of the average employee in the project, causing both direct and indirect losses for workers who are suffering from temporary construction time and other costs.be rooted in the act of it is not safe, so the nature of each task activity is used to analyze the risk of a problem that has occurred. The results of the study showed that the number of accidents could be reduced by an average of 1.0 times/month. It can correct unwanted incidents. It can also improve skills and reduce errors during operations.

Review of Energy Saving Technologies for Urban Rail Vehicles

Jingjie Yan; Wirogana Ruengphrathuengsuka — Sat, 23 Dec 2023 00:00:00 +0700

Urban rail transit systems have substantial power demands, with traction power alone constituting about 50% of the system's electrical consumption. As the operational mileage and number of vehicles increase, so does the energy consumption, underscoring the paramount importance of energy-efficient vehicles. This study systematically analyzes the energy transfer and the dissipation in urban rail transit vehicles. It delves into the potential energy-saving impacts of various strategies and technologies, including vehicle lightweighting, permanent magnet motor traction, silicon carbide applications, regenerative braking energy storage, efficiency enhancement of auxiliary inverters, variable-frequency drive air conditioning, and intelligent lighting systems. By elucidating these methods, this study offers potent strategies to curtail the urban rail transit vehicle energy consumption, thereby bolstering the overall competitiveness of urban rail transit systems.

Current Situation and Progress toward the 2030 Health-related Sustainable Development Goals (SDG 3): A Scoping Review in Thailand

Anunya Pradidthaprecha, Orawan Noiwat, Kultida Bunjongsiri — Sat, 23 Dec 2023 00:00:00 +0700

By adopting the Sustainable Development Goals (SDGs) in 2015, all of the goals are interconnected, even if only SDG 3 focuses on ensuring healthy lives and promoting wellbeing for all people at all ages. The United Nation member set a number of audacious and ambitious health-related goals that must be accomplished by 2030. While one of the SDGs is “health”, several other “health-related” goals also included. Health-related objectives can serve to direct efforts to promote health, direct health policy, and evaluate progress. A goals-setting process almost always results in a higher focus on illness prevention and health promotion. For Agenda 2030 to be realized, integrated implementation across Goals is required. A multistakeholder, multi-actor response is necessary to implement the 2030 Agenda. In addition to discussion between governments, the commercial sector, civil society organizations, and nongovernmental organizations, innovations and advancement in policy, technology, and research are required. Most significantly, a committed community is required. It is essential to comprehend Thailand’s development toward these goals if population health for 70 million citizens is to be improved. While the body of literature already in existence is replete with normative suggestions for potentially helpful measures, there is less evidence of national implementation plans.