Engineering Access

Performance Evaluation of Low-Cost Airborne Infection Isolation Room

Mon, 19 Feb 2024 00:00:00 +0700

This study presents the performance of a low-cost airborne infection isolation room (AIIR). The system consists of an ante room, two AIIRs, a blower, two butterfly valves, an air conditioner, a controller, and a ventilation system. Pressure and temperature sensors were calibrated and installed in all rooms. The control was an in-house system, including Arduino Uno R3, ESP32, NI-USB 6009, and PLC FX5U. PID control was employed to regulate the pressure inside the AIIRs by adjusting the outlet air blower speed. The system was tested under various negative pressures, i.e. -2.5 to -10 Pa, and the effect of inlet opening was also investigated. The results showed that the system effectively controlled the pressure under all experimental conditions. The blower speed and room pressure were found to be related, with higher blower speeds required when all butterfly valves were open. The current of the motor increased with the valve set connected, and the highest current was observed when all butterfly valves were open. The air velocity generated by the blower suction varied with the room pressure, with a decrease in pressure leading to an increase in air velocity. However, for one room operation, the velocity difference was insignificant.

Optimization of Wire Electrical Discharge Machining Process Parameters in AZ91 Magnesium Alloy Using Taguchi-Based Fuzzy Analytic Hierarchy Process (TFAHP) Method

Mon, 19 Feb 2024 00:00:00 +0700

In the electrical discharge machining process optimization domain, a dominant approach to optimization is the Taguchi method, which is favoured for its simplicity and low-cost implementation requirements. However, the results obtained from the Taguchi method have been criticized as susceptible to errors and wrong decisions since it is based on crisp numerical values. Unfortunately, the impact of such wrong decisions cannot be tolerated as it has a chain effect on the non-financial aspects of the organization’s practice such as loss of goodwill. To reverse this issue, research is urgently desired. This article aims to optimize and fuzzifier the electrical discharge machining process parameters using the Taguchi method and the fuzzy analytic hierarchy process method. This article introduces a capturing mechanism of uncertainty and imprecision aspects into the Taguchi method and the Taguchi method has been modified as a new method termed the Taguchi method fuzzy analytic hierarchy process method (T-FAHP). The T-FAHP converts the crisp numerical values into fuzzy numbers which were optimized. The optimal parametric settings and rankings of factors were determined. The optimal parametric settings, delta values, ranks and comparison results were pursued. It was found that the optimal parametric setting did not change from those of the T-AHP results. It yielded A₁B₁C₁D₁E₁F₁ interpreted as pulse on time (160units), pulse off time (40units), pulse current (70 units), gap voltage (20 units), wire feed (4 units) and wire tension (4 units). The ranks were led by pulse current and last by wire feed. The ranking occurred in a different order but the first and the last positions were assigned to pulse current and wire feed, respectively. For the delta values, considering Taguchi AHP against when using the Taguchi-fuzzy analytical hierarchy process, we had a reduction of 16.49% for the pulse current, an increase of 28.57%, for the pulse off time, a decrease of 55.56%, for the gap voltage, no changes, for wire feed, no changes, for wire tension, an increase of roughly 10%. The results obtained from this study are suitable for use by process engineers in the machining industry for cost-effective machining decisions.

Optimization Design of a V-shaped Flux Switching Permanent Magnet Traction motor for Railway Applications

Pattasad Seangwong, Pirat Khunkitti — Mon, 19 Feb 2024 00:00:00 +0700

This paper presents the optimization design of a V-shaped flux-switching permanent magnet motor (V-FSPM) for railway traction applications. The analysis of this V-FSPM involved employing 2-D FEM. Given the complexity of this motor's structure, to achieve accurate and efficient optimization, the comprehensive genetic design optimization method is utilized in this study. This method takes into consideration various sensitivity indices, incorporating design variable sensitivity analysis and genetic algorithm (GA) optimization. The results demonstrate a significant enhancement in the output torque with reduced torque ripple of the proposed V-FSPM motor. These enhancements collectively contribute to the advancement of a more dependable and efficient railway system.

Coupled Taguchi-Pareto-Box Behnken Design-Grey Wolf Optimization Methods for Optimization Decisions when Boring IS 2062 E250 Steel Plates on CNC Machine

Mon, 19 Feb 2024 00:00:00 +0700

Optimizing process parameters in boring operation is extremely important as aids to maintain high resource conservation and efficiency and the free flow of boring data while optimally using boring resources. With optimal parameters, real-time information is offered to process engineers for the practical control the boring operation thus reducing the cost of boring operations. This article presents an investigation on the use of optimization and prioritization in the boring process of IS 2062 E250 steel plates using coupled Taguchi-Pareto-Box Behnken Design-grey wolf optimization approach. The experimental data, drawn from the literature, was initially provided by Patel and Deshpande on CNC TC machine. The objective function, constraints, population size, number of iterations, and fitness function were determined. Then the solution for the grey wolf optimization is generated using the python programming language. Three representative parameters of speed, feed and depth of cut were foundations of the Taguchi’s experimental design used for solving the problem. The optimal parameters were determined from the experiments. For the first time, the coupled Taguchi-Pareto-Box Behnken Design-grey wolf optimization method to make optimization decisions for the boring process. Using 50 iterations and 200 wolfs, the best fitness value of wolves at the end of the 50^th iteration is 872728.53 when the objective function is generated from optimized Box Behnken Design parameters. It also has an optimal solution of speed, feed, depth of cut and nose radius as 800rpm, 0.06,1 and 0, respectively. However, on the application of the regression equation from the Box Behnken Design to form an objective function, using the same 50 iteration and 200 wolves the best fitness value of wolves at the end of 50^th iteration is -51.49 while the optimal parameters are 1189.58, 0.089, 1.22, 0.55 for the speed, feed, depth of cut and nose radius, respectively. Hence, the outcome of this study may be a route to reducing time and money associated with unnecessary usage of non-optimal boring data during operations planning decisions.

An Evaluation of UAV-Derived Aerial Imagery for Estimating the Fresh ABG Biomass of Cassava

Siwa Kaewplang, Thiti Savigamin , Jurawan Nontapon — Mon, 19 Feb 2024 00:00:00 +0700

The objective of this study to estimate the above-ground biomass of cassava using aerial imagery-derived UAV. The cassava plantation aerial imagery by UAV with a 20M pixel camera was acquired by flying at an altitude of 30 meters and 90 meters to compare the ability to estimate the fresh ABG biomass of cassava. The data processing of UAV images was carried out using modern computer vision algorithms for estimating the geometric parameters of cassava to calculate the fresh above-ground biomass of cassava from the allometric equation derived from the measurement of height (H) and the fresh biomass above the ground of the cassava from the cassava plantation. The results showed that the flying altitudes of 30 meters and 90 meters of the accuracy achievement had RMSE values of 0.65 and 0.98 respectively. This study can be used as a guideline for estimating the fresh above ground biomass of cassava plantation with UAV photogrammetry.

The Development of PID Controller by Chess Algorithm

Mon, 19 Feb 2024 00:00:00 +0700

The paper discusses the design and analysis of the control of two interconnected thermal power generation systems using the proportional-integral-derivative (PID) control method, which is further enhanced by the Chess algorithm (CA). Typically, power and control systems exhibit non-linear behavior. Therefore, it is necessary to optimize the automatic gain controllers (AGCs), especially the PID controllers that rely on numerous factors. The Chess algorithms and Particle Swarm Optimization (PSO) have been introduced to enhance the parameterization and evaluate the effectiveness of this method in the context of a dynamic electric load size change approach. Through experimentation, employing the Chess algorithm to enhance the generating system's parameters will render the system more resilient to variations and yield superior performance.

Efficient Waste Detection and Classification based on YOLOv5 Models

Suksun Promboonruang, Thummarat Boonrod, Yongyut Ratchatawetchakul — Mon, 19 Feb 2024 00:00:00 +0700

This paper proposes efficient waste detection and classification based on YOLOv5 by utilizing YOLOv5 for waste detection and classification. Divide the dataset into 4 classes consisting of wood, glass, plastic, and metal. The dataset is methodically divided into three subsets: the training set consisting of 1,860 images, the validation set consisting of 200 images, and the test set consisting of 235 images. The objective of our study is to assess the effectiveness of three YOLOv5 models, namely Yolov5s, Yolov5m, and Yolov5x, across several waste object categories. The methodology employed in this research is as follows: Compilation of datasets and development of models specific to each iteration of YOLOv5. Comparing models. We assess the precision, recall, and mean average precision (mAP) to measure the correctness and speed of their processing. The empirical findings from our investigation suggest that Yolov5x demonstrates the highest level of accuracy and mAP scores (0.41), whilst Yolov5s showcases the shortest processing time (0.83 hours).

The Prototype of Smart Farming System for Installation to Greenhouse using the Internet of Things Technology

Mon, 19 Feb 2024 00:00:00 +0700

This paper proposes a prototype for a smart farming system intended for integration into traditional greenhouses, transforming them into automated environments. Utilizing Internet of Things (IoT) technology, the system dynamically adjusts the conditions to optimize the growth of vegetables. The research methodology consists of seven sequential steps: (1) Exploring possibilities through study and analysis, (2) gathering information on the cultivation of vegetables, (3) designing and developing the prototype system, (4) installing the system in an experimental greenhouse, (5) conducting experiments to observe vegetable growth, (6) collecting data on vegetable growth in the experimental greenhouse, and (7) modifying and enhancing the system based on the collected information. The results indicate that the smart farming system prototype is effective for cultivating Green Oak lettuce. When compared to a non-smart farming system, the average results show significant improvements: canopy width increased by 10.59%, plant height by 11.42%, trunk width by 23.60%, and root length by 14.37%.

Assessing the Impact of Groundwater Variability on Dam Safety Based on Flood Situation and Climate Change Scenarios Using Hydrological Model

Anongrit Kangrang, Phitsanu Srisupaus, Ounla Sivanpheng, Haris Prasanchum — Mon, 19 Feb 2024 00:00:00 +0700

Monitoring dam behavior during severe storms is a crucial step in assessing dam safety. Utilizing hydrological models is considered an effective approach to studying dam safety by analyzing the relationship among hydrological parameters. The objective of this study is to simulate groundwater conditions associated with runoff into the Lam Khan Chu Reservoir in the northeastern region of Thailand. This is achieved by applying the SWAT hydrologic model to simulate daily runoff conditions from 2018 - 2020 and extending the analysis to the future period from 2021 - 2030 using data from the HadGEM2-AO model in RCP4.5 and RCP8.5 scenarios. The aim is to develop criteria for checking dam safety and predicting the impact of future groundwater changes. The results indicated that the SWAT model exhibited good performance in runoff calculation accuracy, as indicated by R², NS, and PBIAS statistical indices. Additionally, the relationship between groundwater level from the SWAT-Check model and those obtained from observation wells was noteworthy. Simulating future dam safety conditions for both RCP4.5 and RCP8.5 forecasts over five years revealed that surveillance measures are necessary for Lam Khan Chu Dam during the rainy season (August - October). This is due to the groundwater showing a trend above normal in the forecasted cases for the specified period. The research methods and findings are anticipated to serve as crucial guidelines for officials overseeing dam safety. These guidelines can be applied to plan preparedness measures, facilitating the timely monitoring and resolution of situations. This applies even to dams or reservoirs lacking a Dam instrument installation.

Energy Efficiency Evaluation for Buildings with Solar Window Technology using BEC Codes of Thailand: Case Study of Skyscrapers in Nanning, China

Mon, 19 Feb 2024 00:00:00 +0700

Energy efficiency and management for buildings plays a more and more important role for modern and smart city development worldwide, especially for glass buildings. The new technology of solar windows allows possibility of increasing renewable energy (RENEW) utilization while decreasing the overall total thermal transfer value (OTTV) based on most global Building Energy Codes. This research proposed an empirical study that explicitly confirmed the successive profile when utilizing solar windows for glass buildings compared to conventional glass windows. Three skyscrapers in Nanning, China (China Resources Center, Nanning Long Guang Century, and Guangxi Financial Plaza) when implementing with the hot summer and warm winter zone BEC such one of Thailand were investigated due to similarity of their annual weathers. The test results showed that the OTTV of the buildings was greatly reduced from 134.90 – 167.30 W/m² to 29.30-40.49 W/m², which was 3.89-4.96 times reduction. The additional renewable energy of 3,525-4,526 MWh/year was generated for solar windows compared with 0 MWh/year the standard glasses, which covering 87-92.2% of the total energy consumption for the buildings (4,058-4911 MWh/year). However, when considering in terms of investment cost, the implementation of solar windows was extremely expensive, reflected by all negative net present value (NPV) of -42 to -64 MRMB. These results revealed that replacing solar windows significantly provided high energy efficiency with additional green energy production, as well as the feasibility of using BEC of Thailand for Naning-Guangxi of China, but extremely high investment cost would still be the main challenge for further research.