English–Chinese Abstract Collection
Abstract of Journal of Engineering Researcher and Lecturer
English–Chinese Abstract Collection
Tensile strength study of mensiang (scirpuss grossus) fibre composites with unsaturated polyester resin matrix
剑草（scirpuss grossus）纤维增强不饱和聚酯树脂基复合材料拉伸强度研究
Evan Hakiim, Hendri Nurdin, Zainal Abadi, Wei-Ting Zhuang
Department of Mechanical Engineering, Faculty of Engineering, Universitas Negeri Padang, Indonesia
Department of Mechanical Engineering, National Cheng Kung University (NCKU), Taiwan
DOI: https://doi.org/10.58712/jerel.v3i3.164
Abstract
The mensiang (scirpuss grossus) is a plant that grows on moist and watery land. Mensiang plants are commonly used by the society to produce mats or bags that have a strong and durable texture. This mensiang plant has fibres that can be used as reinforcement in polymer composites as a substitute for synthetic fibres. In composite manufacturing, one of the important factors in determining strength is the fraction between fibre and matrix. This study was conducted to determine the effect of different volume fractions of composites on the tensile strength of mensiang fibre reinforcement. Extraction of fibre from the stem of the mensiang plant was done manually by combing, so that the fibre was obtained. The fibres were then naturally dried by the sun for 2–3 days. The composite manufacturing process was carried out by using the hand lay-up method. Specimens and tensile testing procedures refer to the ASTM D638 standard. Several specimens were made by varying the fibre and matrix fractions. The test results showed that the 12.5% fibre volume fraction had the highest tensile strength. In this study there was no chemical treatment on the fibres before the lamination process, thus, this can be suggested for future researchers to study on the effect of chemical treatment on mensiang fibres on fibre bonding with the matrix.
摘要
剑草（scirpuss grossus）是一种生长于潮湿及积水环境中的植物。剑草通常被用于编织具有良好强度和耐久性的草席或手提袋。剑草纤维可作为聚合物复合材料中的增强材料，以替代合成纤维。在复合材料制造过程中，影响材料强度的重要因素之一是纤维与基体之间的体积分数。本研究旨在探讨不同复合材料体积分数对剑草纤维增强复合材料拉伸强度的影响。剑草纤维通过人工梳理方式从其茎部提取获得，随后采用自然日晒方式干燥2–3天。复合材料采用手糊成型（hand lay-up）工艺制备。试样制备及拉伸试验均依据 ASTM D638 标准进行。通过改变纤维与基体的体积分数制备了多个试样。测试结果表明，当纤维体积分数为12.5%时，复合材料获得了最高的拉伸强度。本研究在层压成型前未对纤维进行任何化学处理，因此建议未来研究进一步探讨化学处理对剑草纤维与基体界面结合性能的影响。
Keywords: mensiang fiber; natural fiber; nature composite; renewable material
关键词： 剑草纤维；天然纤维；天然复合材料；可再生材料
How to Cite: Hakiim, E., Nurdin, H., Abadi, Z., & Zhuang, W.-T. (2025). Tensile strength study of mensiang (scirpuss grossus) fibre composites with unsaturated polyester resin matrix. Journal of Engineering Researcher and Lecturer, 4(1), 1–8. https://doi.org/10.58712/jerel.v3i3.164
Performance analysis of inserted resonators in microstrip array antenna for biomedical applications
用于生物医学应用的微带阵列天线插入式谐振器性能分析
Cing Nuam Man, Thanda Win, Hla Myo Tun, Mya Mya Aye
Department of Electronic Engineering, Yangon Technological University, Myanmar
Department of Electronic Engineering, Yangon Technological University, Myanmar
DOI: https://doi.org/10.58712/jerel.v4i1.177
Abstract
This paper investigates the use of inserted resonators in designing microstrip patch array antenna for biomedical applications, such as respiratory rate detection. The purpose of this study is to analyze size and placement of resonator, and slots which influence the overall performance. The antenna was constructed by connecting two single microstrip patch antennas (11.7 mm × 15.7 mm × 1.6 mm) on an FR4 substrate with a dielectric constant (εr = 4.4) to form (26 mm × 50 mm × 1.6 mm). It achieves a miniaturized design of the expected resonance frequency with directional polarization, and provides good gain and bandwidth. The simulations were operated using FEKO software. The results and size of antenna were compared with references designs. The antenna was also designed for a 5–6 GHz frequency range, making it suitable for ISM band (Industrial, Medical, and Science) applications, low-power wireless applications including Wi-Fi and Bluetooth, as well as robotic systems, low-noise amplifier (LNA), 5G applications, and WiFi 6E standard applications.
摘要
本文研究了插入式谐振器在微带贴片阵列天线设计中的应用，面向生物医学领域，如呼吸频率检测。研究旨在分析谐振器的尺寸、布局位置以及开槽结构对天线整体性能的影响。该天线采用介电常数为 εr = 4.4 的 FR4 基板，将两个尺寸为 11.7 mm × 15.7 mm × 1.6 mm 的单微带贴片天线连接组成尺寸为 26 mm × 50 mm × 1.6 mm 的阵列结构。该设计在实现预期谐振频率小型化的同时，具有定向极化特性，并能够提供良好的增益和带宽。仿真采用 FEKO 软件完成，并将所得结果及天线尺寸与参考设计进行了比较。此外，该天线工作于 5–6 GHz 频段，适用于 ISM（工业、医疗与科学）频段、低功耗无线通信应用（包括 Wi-Fi 和 Bluetooth），以及机器人系统、低噪声放大器（LNA）、5G 应用和 WiFi 6E 标准等应用场景。
Keywords: microstrip patch array antenna; FR4 substrate; resonance frequency; resonator
关键词： 微带贴片阵列天线；FR4 基板；谐振频率；谐振器
How to Cite: Man, C. N., Win, T., Tun, H. M., & Aye, M. M. (2025). Performance analysis of inserted resonators in microstrip array antenna for biomedical applications. Journal of Engineering Researcher and Lecturer, 4(1), 9–21. https://doi.org/10.58712/jerel.v4i1.177
A concave impeller: A new modified semi-open impeller for higher performance of centrifugal pumps
凹形叶轮：一种提升离心泵性能的新型改进半开式叶轮
Rahmat Azis Nabawi, Egi Fadillah, Haris Shiddiq Mulyadi, Muhammad Shadiq Fahrezi, Firza Fernanda Putra
Department of Mechanical Engineering, Faculty of Engineering, Universitas Negeri Padang, Indonesia
DOI: https://doi.org/10.58712/jerel.v4i1.178
Abstract
The performance enhancement of centrifugal pumps is continuously pursued to meet increasingly complex operational demands. Ongoing improvements in pump component design, particularly the impeller, are essential to achieving optimal configurations. The impeller is a critical component that significantly influences the overall performance of centrifugal pumps. This study aims to develop an impeller design that offers higher performance compared to the original one. The methodology utilized was Computational Fluid Dynamics (CFD). The primary focus was on modifying the semi-open impeller type. Two modified impellers were developed with concave and convex design. They were simulated and compared to the original impeller configuration. The simulation results indicate that pressure distribution at the inlet remains similar for all designs. However, pressure variations at the outlet and differences in volumetric flow rate between inlet and outlet were found. The contour visualization of pressure and flow velocity for each impeller configuration shown from the CFD simulation results is further discussed, in terms of pressure distribution and flow trajectory pressure.
摘要
为了满足日益复杂的运行需求，提高离心泵性能一直是相关研究持续追求的目标。持续优化泵关键部件，尤其是叶轮的设计，对于实现最佳性能配置至关重要。叶轮作为离心泵的核心部件，对整机性能具有决定性影响。本研究旨在开发一种较原始设计具有更高性能的新型叶轮。研究采用计算流体力学（Computational Fluid Dynamics，CFD）方法，以半开式叶轮为主要改进对象，设计了两种改进型叶轮，分别为凹形和凸形结构，并将其与原始叶轮进行了仿真对比分析。仿真结果表明，各种叶轮设计在进口处的压力分布基本一致。然而，在出口处的压力分布以及进口与出口之间的体积流量方面均存在明显差异。本文进一步结合 CFD 仿真所得的压力和流速云图，对不同叶轮结构的压力分布特性及流动轨迹进行了分析与讨论。
Keywords: centrifugal pump; impeller design; CFD simulation; pressure distribution; volume flow rate; semi-open impeller
关键词： 离心泵；叶轮设计；CFD 仿真；压力分布；体积流量；半开式叶轮
How to Cite: Nabawi, R. A., Fadillah, E., Mulyadi, H. S., Fahrezi, M. S., & Putra, F. F. (2025). A concave impeller: A new modified semi-open impeller for higher performance of centrifugal pumps. Journal of Engineering Researcher and Lecturer, 4(1), 22–30. https://doi.org/10.58712/jerel.v4i1.178
Students’ regional potential-based project for vocational education in engineering field
基于学生区域潜力的工程领域职业教育项目学习
Syahril Syahril, Rizky Ema Wulansari, Dian Safitri, Tee Tze Kiong, Sokolova Elizaveta Vitalyevna, Agariadne Dwinggo Samala
Department of Mechanical Engineering, Faculty of Engineering, Universitas Negeri Padang, Indonesia
Department of English Language and Literature, Universitas Negeri Padang, Indonesia
Faculty of Technical and Vocational Education, Universiti Tun Hussein Onn Malaysia, Malaysia
Specialist of the Science Metrics Department, Ural State University of Economics, Russian Federation
Department of Electronics, Faculty of Engineering, Universitas Negeri Padang, Indonesia
DOI: https://doi.org/10.58712/jerel.v4i1.180
Abstract
This article discusses Students’ Regional Potential-based Project for Vocational Education in Engineering Field as a strategy to strengthen the quality of project-based learning implementation, covering project-based learning, a project task based on potential of student’s region, the seven standard elements on a project task based on potential of student’s region, the stages of the implementation, and its effectiveness. It was driven by the existence of enormous potentials in Indonesia which have not been optimally developed. Most of universities here are located in urban areas, while most of the students come from rural regions. The previous research discloses students’ positive perceptions toward this learning implementation. It helps them develop their soft skills, fosters better engagement with the learning process, and improves their 4C skills (Critical Thinking, Communication, Collaboration, and Creativity). The approach is able to serve as a model for vocational education learning, particularly in the field of engineering. It not only provides students with the opportunity to acquire knowledge, technology, and soft skills, but also contributes to students’ regional development. This article is highly beneficial for learning implementation in Indonesia, particularly in vocational education, as well as a reference for further studies.
摘要
本文探讨了基于学生区域潜力的工程领域职业教育项目学习，作为提升项目式学习（Project-Based Learning）实施质量的一种策略。内容涵盖项目式学习、基于学生所在地区潜力的项目任务、项目任务的七项标准要素、实施阶段以及实施效果。该研究源于印度尼西亚拥有丰富但尚未得到充分开发的区域资源潜力。印度尼西亚多数高校位于城市，而大多数学生来自农村地区。既有研究表明，学生对该教学模式持积极态度。该模式有助于培养学生的软技能，提高其学习参与度，并提升其4C能力（Critical Thinking、Communication、Collaboration 和 Creativity）。该方法可作为职业教育，尤其是工程领域职业教育的重要教学模式。它不仅为学生提供了获取知识、技术和软技能的机会，同时也有助于促进学生所在地区的发展。本文对于印度尼西亚职业教育，特别是工程职业教育中的教学实施具有重要参考价值，同时也可为后续相关研究提供借鉴。
Keywords: project-based learning; vocational education; engineering student; regional potential
关键词：项目式学习；职业教育；工程专业学生；区域潜力
How to Cite: Syahril, S., Wulansari, R. E., Safitri, D., Kiong, T. T., Vitalyevna, S. E., & Samala, A. D. (2025). Students’ regional potential-based project for vocational education in engineering field. Journal of Engineering Researcher and Lecturer, 4(1), 39–51. https://doi.org/10.58712/jerel.v4i1.180
The effectiveness of project tasks on students’ regional potential-based to increase students’ knowledge
基于学生区域潜力的项目任务提高学生知识水平的有效性
Dinda Khaira Latifa, Rezkilaturahmi Rezkilaturahmi
Department of Technology and Vocational Education, Graduate School, Universitas Negeri Yogyakarta, Indonesia
Department of Educational Research and Evaluation, Graduate School, Universitas Negeri Yogyakarta, Indonesia
DOI: https://doi.org/10.58712/jerel.v4i1.175
Abstract
The industrial world needs professionals who are able to align the needs of the market. Its intense market competition not only demands the ability to work, but also the ability to create innovative products. Therefore, higher education must prepare excellent graduates with those ability. One of the efforts is to improve the learning model by implementing Project Tasks on Students’ Regional Potential. This study belongs to pre-experimental research with a one-group pretest-posttest design, subjected to 30 students of D3 Mechanical Engineering study program. Based on the research results, it can be concluded that the students who were taught by Project Tasks on Students’ Regional Potential got significant improvement from their pre-test to post-test scores. Consequently, it can be interpreted as there was an effect of the Project Tasks treatment given to research subjects. Therefore, this model can be referred as an effective model to adapt, implemented on learning for vocational higher education.
摘要
工业领域需要能够满足市场需求的专业人才。激烈的市场竞争不仅要求从业人员具备工作能力，还要求具备创新产品开发能力。因此，高等教育必须培养具备这些能力的优秀毕业生。改进教学模式的措施之一是实施基于学生区域潜力的项目任务（Project Tasks on Students’ Regional Potential）。本研究属于前实验研究，采用单组前测–后测（one-group pretest-posttest）研究设计，以30名机械工程专科（D3）专业学生为研究对象。研究结果表明，接受基于学生区域潜力项目任务教学的学生，其后测成绩较前测成绩有显著提高。因此，可以认为所实施的项目任务教学对研究对象产生了积极影响。由此可见，该教学模式可作为一种有效的职业高等教育教学模式，并可推广应用于职业教育教学实践。
Keywords: project-based learning; vocational education; engineering student; regional potential
关键词：项目式学习；职业教育；工程专业学生；区域潜力
How to Cite: Latifa, D. K., & Rezkilaturahmi, R. (2025). The effectiveness of project tasks on students’ regional potential-based to increase students’ knowledge. Journal of Engineering Researcher and Lecturer, 4(1), 31–38. https://doi.org/10.58712/jerel.v4i1.175
Comparative study on energy absorption capacities of normal and rubberized concrete columns under sinusoidal wave
正弦波作用下普通混凝土与橡胶混凝土柱能量吸收能力的比较研究
Cho Zin Win, Khin Su Su Htwe, Nyan Myint Kyaw
Department of Civil Engineering, Yangon Technological University, Myanmar
DOI: https://doi.org/10.58712/jerel.v4i2.183
Abstract
This research explores the use of rubberized concrete composite as an innovative structural material designed to improve energy dissipation and enhance seismic resistance by incorporating recycled rubber crumb into concrete. A reference test model was constructed using normal concrete, while the remaining models were made from concrete in which a portion of the fine aggregates was partially replaced with crumb rubber particles. Lumped mass columns were tested on a shaking table using sine wave excitation to evaluate dynamic behaviour and seismic response with 4 Hz sinusoidal base motion. Acceleration measurements were obtained and analysed in MATLAB using Fast Fourier Transform (FFT), allowing for comparison between normal and rubberized concrete specimens. The results indicated that as the rubber content in the concrete increased, the frequency of the columns decreased under base excitation. Additionally, three-dimensional finite element simulations of lumped mass column models were conducted in ANSYS. Linear dynamic analysis was conducted to assess the system’s behaviour when subjected to harmonic loading. In addition, resonance conditions were also considered to assess the dynamic interaction of the column. With higher rubber content, the acceleration response is reduced due to the enhanced damping and energy absorption capabilities of rubberized concrete, leading to a significant decrease in peak acceleration values.
摘要
本研究探讨了橡胶混凝土复合材料作为一种创新结构材料的应用，通过在混凝土中掺入再生橡胶颗粒，提高结构的能量耗散能力和抗震性能。参考试件采用普通混凝土制作，其余试件则以橡胶颗粒部分替代细骨料制备橡胶混凝土。采用振动台对集中质量柱进行4 Hz正弦基底激励试验，以评估其动力特性和抗震响应。加速度数据通过 MATLAB 中的快速傅里叶变换（Fast Fourier Transform，FFT）进行分析，以比较普通混凝土与橡胶混凝土试件的动力响应差异。结果表明，随着混凝土中橡胶含量的增加，柱体在基底激励下的固有频率逐渐降低。此外，利用 ANSYS 建立了集中质量柱的三维有限元模型，并进行了线性动力分析，以评估结构在谐波荷载作用下的动力响应。同时，还考虑了共振工况，以分析柱体的动力相互作用。随着橡胶掺量的增加，橡胶混凝土因其优异的阻尼性能和能量吸收能力，使结构加速度响应明显降低，从而显著减小了峰值加速度。
Keywords: rubberized concrete; energy absorption; sinusoidal wave; acceleration response
关键词：橡胶混凝土；能量吸收；正弦波；加速度响应
How to Cite: Win, C. Z., Htwe, K. S. S., & Kyaw, N. M. (2025). Comparative study on energy absorption capacities of normal and rubberized concrete columns under sinusoidal wave. Journal of Engineering Researcher and Lecturer, 4(2), 52–65. https://doi.org/10.58712/jerel.v4i2.183
System dynamics modelling of integrated urban clean water management: A case study in Padang City, Indonesia
城市综合清洁供水管理系统动力学建模：印度尼西亚巴东市案例研究
Yaumal Arbi, Rumia Ramadhianty, Shinta Rahayu, Widia Putri
Department of Civil Engineering, Faculty of Engineering, Universitas Negeri Padang, Indonesia
Department of Environmental Engineering, Faculty of Engineering, Universitas Andalas, Indonesia
DOI: https://doi.org/10.58712/jerel.v4i2.184
Abstract
Access to clean water is essential for human life and a key target of Sustainable Development Goal (SDG) 6: Clean Water and Sanitation. However, cities in developing countries, including Padang City, Indonesia, face significant challenges in meeting the growing demand due to population growth and limited water infrastructure. This study used system dynamics modelling approach with Powersim Studio 10 to develop an integrated clean water management system for Padang City. The model simulates the dynamics of population growth, water consumption, production, and distribution efficiency over a 20-year period (2022–2042). Several policy scenarios—optimistic, moderate, and pessimistic—were tested to evaluate their impact on water availability. The baseline scenario predicts a continuous decline in clean water supply due to increasing population, high leakage rates (11.99%), and water wastage (2%), which surpass the water production growth rate (5.01%). As a result, a water deficit is expected. However, under the optimistic scenario, with increased production (10%), reduced leakage (8%), and reduced wastage (3%), Padang City could achieve a clean water surplus by 2042. The moderate and pessimistic scenarios still result in a deficit. This research highlights the value of the system dynamics modelling in forecasting urban water demand and assessing policy impacts. The findings emphasize the need for integrated planning, combining technical solutions and behavioural change, to ensure sustainable water management and support the achievement of SDG 6.
摘要
清洁用水是人类生存的基本需求，也是可持续发展目标（SDG）6——“清洁饮水与卫生设施”的核心目标之一。然而，包括印度尼西亚巴东市在内的发展中国家城市，由于人口增长和供水基础设施有限，在满足日益增长的用水需求方面面临巨大挑战。本研究采用系统动力学建模方法，并利用 Powersim Studio 10 构建巴东市综合清洁供水管理系统模型。该模型模拟了2022—2042年20年期间人口增长、用水量、供水量以及供水效率的动态变化。研究设计了乐观、中等和悲观三种政策情景，以评估不同政策对清洁供水能力的影响。基准情景预测，由于人口持续增长、供水管网漏损率较高（11.99%）以及水资源浪费（2%）超过供水增长率（5.01%），巴东市未来将面临清洁供水短缺。然而，在乐观情景下，通过将供水增长率提高至10%、漏损率降低至8%、水资源浪费降低至3%，预计到2042年巴东市可实现清洁供水盈余。而中等和悲观情景仍将出现供水不足。本研究表明，系统动力学建模能够有效预测城市用水需求并评估不同政策的实施效果。研究结果强调，应通过技术措施与公众行为改变相结合的综合规划，实现可持续水资源管理，并支持实现可持续发展目标6。
Keywords: system dynamics; urban water management; policy scenario; clean water sustainability; clean water and sanitation
关键词：系统动力学；城市水资源管理；政策情景；清洁供水可持续性；清洁饮水与卫生设施
How to Cite: Arbi, Y., Ramadhianty, R., Rahayu, S., & Putri, W. (2025). System dynamics modelling of integrated urban clean water management: A case study in Padang City, Indonesia. Journal of Engineering Researcher and Lecturer, 4(2), 66–76. https://doi.org/10.58712/jerel.v4i2.184
Optimization of Artec Leo 3D Scanner parameters for object accuracy using the Taguchi Method
基于田口方法优化 Artec Leo 三维扫描仪参数以提高对象扫描精度
Ananda Jafron Rhionaldo, Rifelino Rifelino, Delima Yanti Sari, Febri Prasetya
Department of Mechanical Engineering, Faculty of Engineering, Universitas Negeri Padang, Indonesia
DOI: https://doi.org/10.58712/jerel.v4i2.186
Abstract
This study focuses on optimizing the scanning parameters of the Artec Leo 3D Scanner to enhance scanning accuracy by minimizing geometric deviations. The experimental design utilizes the Taguchi L4(2³) orthogonal array method to examine the influence of three scanning factors: distance, angle, and lighting at two levels. A 16-inch car wheel, chosen for its geometric complexity, was scanned under various parameter combinations. The results indicated that the combination of indoor lighting, a 45° angle, and a scanning distance of 100 cm yielded the smallest deviation (0.5%) and the highest signal-to-noise (S/N) ratio (6.02 dB). Analysis of variance (ANOVA) revealed that the scanning distance contributed the most to the variation in scanning accuracy (65.09%), followed by lighting (34.64%) and angle (0.27%). A confirmation test with the optimal parameters further reduced the deviation to 0.4%, validating the effectiveness of the Taguchi method for parameter optimization. This study’s findings contribute valuable insights for industries that require high-precision 3D models, such as aerospace, automotive, and healthcare. The research demonstrates the importance of optimizing scanning parameters and offers a practical approach to improving 3D scanning processes. Future research can expand by exploring environmental conditions, scan resolution, and machine learning integration for real-time adjustments.
摘要
本研究旨在优化 Artec Leo 三维扫描仪的扫描参数，通过最小化几何偏差来提高扫描精度。实验采用田口 L4(2³) 正交表设计方法，研究扫描距离、扫描角度和照明条件三个因素在两个水平下对扫描精度的影响。选取具有复杂几何形状的16英寸汽车轮毂作为扫描对象，在不同参数组合下进行扫描实验。结果表明，室内照明、45°扫描角度以及100 cm扫描距离的组合获得了最小几何偏差（0.5%）和最高信噪比（S/N）（6.02 dB）。方差分析（ANOVA）结果显示，扫描距离对扫描精度变化的贡献率最高（65.09%），其次为照明条件（34.64%），扫描角度的影响最小（0.27%）。采用最优参数进行确认试验后，几何偏差进一步降低至0.4%，验证了田口方法在参数优化中的有效性。本研究成果可为航空航天、汽车制造及医疗等需要高精度三维模型的行业提供重要参考，同时表明优化扫描参数对于提升三维扫描质量具有重要意义，并为未来结合环境条件、扫描分辨率以及机器学习实现实时参数优化提供了研究方向。
Keywords: 3D scanner; Artec Leo; scanning accuracy; Taguchi; geometric deviation
关键词：三维扫描仪；Artec Leo；扫描精度；田口方法；几何偏差
How to Cite: Rhionaldo, A. J., Rifelino, R., Sari, D. Y., & Prasetya, F. (2025). Optimization of Artec Leo 3D Scanner parameters for object accuracy using the Taguchi Method. Journal of Engineering Researcher and Lecturer, 4(2), 77–89. https://doi.org/10.58712/jerel.v4i2.186
The effectiveness of the STAD Cooperative Learning Method assisted by Flashcard Media in improving students’ learning outcomes
Flashcard 媒体辅助 STAD 合作学习法提高学生学习成效的有效性
Yoan Alfarezy Indra, Febri Prasetya, Primawati Primawati, Zainal Abadi
Department of Mechanical Engineering, Faculty of Engineering, Universitas Negeri Padang, Indonesia
DOI: https://doi.org/10.58712/jerel.v4i2.187
Abstract
This study explores the effectiveness of the Student Teams Achievement Divisions (STAD) cooperative learning model, supported by flashcard media, in enhancing student learning outcomes in Manufacturing Technical Drawing at SMK Negeri 1 West Sumatra. A quasi-experimental control group design was employed, where the experimental group used the STAD method integrated with flashcards, and the control group received traditional lecture-based instruction. Post-test results showed that the experimental group significantly outperformed the control group, achieving a higher mean score of 79.68 compared to 63.84, with an N-Gain score of 50.81%, indicating moderate improvement. The study found that the STAD model, combined with flashcards, boosted academic achievement and promoted more consistent and equitable learning outcomes. Flashcards played a vital role by simplifying complex concepts and enhancing student engagement. This study fills a gap in vocational education by demonstrating the effectiveness of combining cooperative learning and visual aids in technical education. The research offers valuable insights for educators in similar contexts, proposing a cost-effective and scalable instructional method that can be applied across various technical disciplines. However, the study’s limitation lies in its short-term implementation, and further research is needed to explore the long-term effects of this combined learning strategy.
摘要
本研究探讨了 Flashcard 媒体辅助学生团队成就分组法（Student Teams Achievement Divisions，STAD）合作学习模式在提高西苏门答腊国立第一职业中学（SMK Negeri 1 West Sumatra）制造技术制图课程学生学习成效方面的有效性。研究采用准实验控制组设计，实验组实施结合 Flashcard 的 STAD 教学模式，对照组采用传统讲授法。后测结果表明，实验组学习成绩显著优于对照组，平均成绩达到79.68分，高于对照组的63.84分；N-Gain值为50.81%，表明学生学习成效达到中等提升水平。研究结果显示，STAD 合作学习模式结合 Flashcard 教学媒体不仅能够提高学生的学业成绩，而且能够促进更加稳定、公平的学习效果。Flashcard 在简化复杂概念和提高学生课堂参与度方面发挥了重要作用。本研究通过验证合作学习与视觉辅助教学相结合在技术教育中的有效性，填补了职业教育领域相关研究的不足。研究成果可为类似教育环境中的教师提供有价值的参考，并提出一种成本较低、易于推广、可应用于多个技术学科的教学方法。然而，本研究的局限在于实施周期较短，未来仍需进一步探讨该教学策略的长期应用效果。
Keywords: STAD cooperative learning; flashcard media; manufacturing technical drawing; vocational education; learning outcomes
关键词：STAD 合作学习；Flashcard 教学媒体；制造技术制图；职业教育；学习成效
How to Cite: Indra, Y. A., Prasetya, F., Primawati, P., & Abadi, Z. (2025). The effectiveness of the STAD Cooperative Learning Method assisted by Flashcard Media in improving students’ learning outcomes. Journal of Engineering Researcher and Lecturer, 4(2), 90–102. https://doi.org/10.58712/jerel.v4i2.187
Enhancing vocational education through augmented reality: Android-based learning media for CNC TU-2A instruction in technical and vocational high schools
通过增强现实提升职业教育：面向职业高中的 CNC TU-2A 安卓学习媒体
Rezky Azhari Salim, Syahril Syahril, Nelvi Erizon
Department of Mechanical Engineering, Faculty of Engineering, Universitas Negeri Padang, Indonesia
DOI: https://doi.org/10.58712/jerel.v4i2.188
Abstract
The rapid evolution of digital technologies has opened new opportunities for transforming vocational education, particularly in CNC (Computer Numerical Control) machining. Despite its vital role in preparing skilled workers, CNC instruction in Indonesian vocational schools remains constrained by teacher-cantered methods, static materials, and limited access to costly machines, resulting in low engagement and achievement. This study aimed to design, implement, and evaluate Android-based Augmented Reality (AR) learning media for CNC TU-2A machines to enhance students’ cognitive performance, psychomotor skills, and classroom participation. Using a Classroom Action Research (CAR) model across two cycles, the research involved 31 eleventh-grade Mechanical Engineering students at SMK Negeri 5 Padang. Data were collected through cognitive tests, student activity observations, and surveys. Results showed significant improvements: average cognitive scores rose from 75.91 to 82.47, classical mastery increased from 54.83% to 100%, and psychomotor scores improved by 3.24 points. Student learning activities also climbed from 72.2% to 80.4%, with discussion and collaboration showing the highest gain (17%). While barriers such as device limitations and technical issues arose, they were addressed through device sharing, offline content, and teacher mentoring. Findings confirm AR as an effective, scalable tool for modernizing CNC instruction, fostering engagement, and preparing vocational students for Industry 4.0 learning demands.
摘要
数字技术的快速发展为职业教育转型，特别是数控（Computer Numerical Control，CNC）加工教学，提供了新的机遇。尽管 CNC 教学在培养高技能人才方面具有重要作用，但印度尼西亚职业学校的 CNC 教学仍受限于以教师为中心的教学方式、静态教学材料以及昂贵设备获取受限等因素，导致学生学习参与度和学习成效较低。本研究旨在设计、开发并评估基于 Android 的增强现实（Augmented Reality，AR）学习媒体，用于 CNC TU-2A 机床教学，以提升学生的认知能力、动作技能（psychomotor skills）和课堂参与度。研究采用课堂行动研究（Classroom Action Research，CAR）两轮循环模式，以巴东第五国立职业高中（SMK Negeri 5 Padang）31名十一年级机械工程专业学生为研究对象。数据通过认知测试、学生学习活动观察及问卷调查收集。研究结果表明，学生平均认知成绩由75.91提高至82.47，班级整体达标率由54.83%提高至100%，动作技能得分提高3.24分。学生学习活动参与率也由72.2%提升至80.4%，其中讨论与合作能力提升最为显著（17%）。虽然研究过程中存在设备不足及技术问题等障碍，但通过设备共享、离线学习内容和教师指导等方式得到有效解决。研究结果证实，增强现实技术是一种高效且易于推广的现代化 CNC 教学工具，能够有效提高学生学习参与度，并帮助职业教育学生更好地适应工业4.0时代的人才培养需求。
Keywords: augmented reality; CNC TU-2A; Android learning media; vocational education; student engagement; psychomotor skills
关键词：增强现实；CNC TU-2A；Android 学习媒体；职业教育；学生参与度；动作技能
How to Cite: Salim, R. A., Syahril, S., & Erizon, N. (2025). Enhancing vocational education through augmented reality: Android-based learning media for CNC TU-2A instruction in technical and vocational high schools. Journal of Engineering Researcher and Lecturer, 4(2), 103–114. https://doi.org/10.58712/jerel.v4i2.188
Automated drip rate monitoring and control system for intravenous fluids of varying viscosities
适用于不同黏度静脉输液的自动滴速监测与控制系统
Justin Suarez, Allain Jessel Macas
Department of Electronics Engineering, University of Science and Technology of Southern Philippines, Philippines
DOI: https://doi.org/10.58712/jerel.v4i3.192
Abstract
Nurses play an essential role in society by advocating for health promotion, educating the public and patients on injury and sickness prevention, engaging in rehabilitation, and giving care and support. However, increasing patient loads significantly affect nurses’ available time for critical tasks, such as monitoring intravenous (IV) fluid flow. The accuracy of IV administration can also be affected by the viscosity of the infused fluid, making precise drip rate control challenging. This study aims to develop a cost-effective IV fluid monitoring and flow rate control device using a Raspberry Pi Pico microcontroller board. The device would enable nurses to monitor and control the IV drip rate accurately and easily. The accuracy of a prototype sensor for measuring drip rates in different fluids with varying viscosities is evaluated through comparison with a manual method. The results indicate that the experimental method shows good agreement and accuracy compared to the manual method, with minor biases and acceptable ranges of differences. Control charts demonstrate higher precision in the experimental method, indicating stable and consistent measurements. Overall, the findings suggest that the prototype is effective in measuring drip rates and has potential for drip rate monitoring applications. The prototype demonstrated excellent performance in handling fluids of varying viscosities, surpassing 85%. The average percentage errors were 7.5% for Sodium Chloride, 7.67% for Hetastarch, and 8.09% for fresh milk. The prototype demonstrates the ability to enhance safety and precision in IV infusions.
摘要
护士在促进健康、开展公众和患者健康教育、预防疾病与损伤、参与康复治疗以及提供护理和支持等方面发挥着至关重要的作用。然而，随着患者数量不断增加，护士用于执行关键护理任务（如监测静脉输液（Intravenous，IV）流速）的时间受到显著影响。此外，输注液体的黏度差异也会影响静脉输液的准确性，使滴速的精确控制更加困难。本研究旨在基于 Raspberry Pi Pico 微控制器开发一种低成本的静脉输液监测与流速控制装置，以帮助护士更加准确、便捷地监测和控制 IV 输液滴速。研究通过与人工测量方法进行比较，对原型传感器在测量不同黏度液体滴速时的准确性进行了评估。结果表明，该实验方法与人工测量结果具有良好的一致性和较高的准确性，仅存在较小的系统偏差，并且误差范围处于可接受水平。控制图分析进一步表明，该实验方法具有更高的测量精度，能够实现稳定且一致的测量结果。总体而言，研究结果证明该原型装置能够有效测量滴速，具有应用于滴速监测系统的潜力。该原型在处理不同黏度液体时表现优异，整体性能均超过85%。其中，对氯化钠溶液（Sodium Chloride）、羟乙基淀粉（Hetastarch）和鲜牛奶（fresh milk）的平均百分比误差分别为7.5%、7.67%和8.09%。研究结果表明，该原型系统能够有效提高静脉输液过程的安全性和控制精度。
Keywords: intravenous (IV) therapy; IV fluid monitoring; drip rate control; viscosity
关键词：静脉输液（IV）治疗；静脉输液监测；滴速控制；黏度
How to Cite: Suarez, J., & Macas, A. J. (2025). Automated drip rate monitoring and control system for intravenous fluids of varying viscosities. Journal of Engineering Researcher and Lecturer, 4(3), 115–124. https://doi.org/10.58712/jerel.v4i3.192
Nickel mining on small islands and the conservation mandate: A regulatory review and policy analysis based on the Raja Ampat case study
小岛镍矿开采与生态保护使命：基于拉贾安帕特案例的法规审查与政策分析
Wahyudi Zahar, Fadhila Achmadi Rosyid
Earth Resources Exploration Research Group, Faculty of Mining and Petroleum Engineering, Doctoral Program in Mining Engineering, Institut Teknologi Bandung, Indonesia
Mining Engineering Research Group, Faculty of Mining and Petroleum Engineering, Institut Teknologi Bandung, Indonesia
DOI: https://doi.org/10.58712/jerel.v4i3.195
Abstract
Indonesia plays a strategic role in global mineral supply, but the expansion of mining into coastal–small-island areas demand governance that balances downstreaming objectives with the conservation mandate. This article presents a regulatory review and policy analysis illustrated by the Raja Ampat case. The policy framework examined includes Government Regulation (PP) No. 25 of 2024, Ministry of Energy and Mineral Resources Regulation (Permen ESDM) No. 15 of 2024, and Ministerial Decree (Kepmen ESDM) No. 177.K/MB.01/MEM.B/2024. The analysis shows that: (i) licensing and enforcement instruments have been strengthened, as reflected in corrective actions against non-compliant permits; (ii) in small-island contexts with high conservation value, the principal risks stem from sedimentation and declining water quality, which affect coral-reef ecosystems and fisheries–tourism livelihoods; and (iii) the effectiveness of regulations is highly determined by consistency of implementation, data traceability, and public participation. Policy recommendations include indicator-based enforcement (quarterly inspections and an RKAB compliance dashboard), a sediment-focused “AMDAL+” environmental impact assessment for coastal–reef settings, synchronizing a “small-island/geopark” filter in WIUP/WIUPK designation, supply-chain transparency, and strengthening local economic alternatives that are compatible with conservation. The findings affirm that a balance between economic growth and ecosystem sustainability can be achieved through a combination of stringent licensing screening, adaptive monitoring, and transparent governance.
摘要
印度尼西亚在全球矿产资源供应中具有重要的战略地位。然而，采矿活动向沿海及小岛地区的扩张，要求建立能够兼顾矿产下游产业发展目标与生态保护使命的治理体系。本文以拉贾安帕特（Raja Ampat）案例为例，开展法规审查与政策分析。研究所依据的政策框架包括《2024年第25号政府条例》（Government Regulation/PP No. 25 of 2024）、《2024年第15号能源与矿产资源部长条例》（Permen ESDM No. 15 of 2024）以及《2024年第177.K/MB.01/MEM.B/2024号部长决定》（Kepmen ESDM No. 177.K/MB.01/MEM.B/2024）。分析结果表明：（i）许可管理和执法机制已得到强化，体现在对不符合规定许可证采取的纠正措施；（ii）在具有高度生态保护价值的小岛地区，主要风险来源于泥沙沉积和水质下降，这将影响珊瑚礁生态系统以及渔业与旅游业生计；（iii）法规实施效果在很大程度上取决于执行的一致性、数据可追溯性以及公众参与程度。本文建议采取基于指标的监管措施（包括季度检查和 RKAB 合规仪表板）、针对沿海珊瑚礁环境的“AMDAL+”环境影响评价、在 WIUP/WIUPK 划定中同步引入“小岛/地质公园”筛选机制、提高供应链透明度，并加强符合生态保护要求的地方替代产业发展。研究结果表明，通过严格的许可审查、自适应监测和透明治理相结合，可以实现经济增长与生态系统可持续发展的平衡。
Keywords: mineral mining; small islands; conservation; environmental policy
关键词：矿产开采；小岛；生态保护；环境政策
How to Cite: Zahar, W., & Rosyid, F. A. (2025). Nickel mining on small islands and the conservation mandate: A regulatory review and policy analysis based on the Raja Ampat case study. Journal of Engineering Researcher and Lecturer, 4(3), 125–135. https://doi.org/10.58712/jerel.v4i3.195
Influence of fiber content and applied load on the wear mechanisms of oil palm frond fiber/phenol-formaldehyde composites with functional fillers
纤维含量与载荷对功能填料油棕榈叶柄纤维/酚醛复合材料磨损机理的影响
Budi Istana, Indra Hasan, Kuntang Winangun
Department of Mechanical Engineering, Faculty of Engineering, Universitas Muhammadiyah Riau, Indonesia
Department of Mechanical Engineering, Faculty of Engineering, Universitas Muhammadiyah Riau, Indonesia
Department of Mechanical Engineering, Universitas Muhammadiyah Ponorogo, Indonesia
DOI: https://doi.org/10.58712/jerel.v4i3.198
Abstract
The tribological behavior of oil palm fiber (OPF)-reinforced polymer composites was investigated with varying fiber contents (10, 20, and 30 wt.%) under different applied loads (20, 40, and 60 N) at a sliding speed of 2.5 m/s. Experimental results show that wear rate decreases significantly with increasing fiber content up to 20 wt.% at all loads, reaching minimum values of 1.2, 2.1, and 3.9 ×10-4 mm³/Nm at 20, 40, and 60 N, respectively. Beyond 20 wt.%, wear rate increases, indicating fiber agglomeration and interfacial defects at higher loadings. A second-degree polynomial regression model was developed to predict wear rate as a function of fiber content and load. Model analysis and contour mapping identified an optimum wear resistance region centered at 20 wt.% fiber content and ~35–45 N load. The improved wear performance at this composition is attributed to enhanced fiber–matrix adhesion, improved stress transfer, and reduced microstructural discontinuities. These findings suggest that OPF composites with 20 wt.% reinforcement provide optimal wear resistance under moderate load conditions, making them promising candidates for tribological applications such as automotive and industrial components.
摘要
本研究考察了不同油棕榈纤维（Oil Palm Fiber，OPF）含量（10、20 和 30 wt.%）的聚合物复合材料在不同载荷（20、40 和 60 N）及滑动速度为 2.5 m/s 条件下的摩擦磨损性能。实验结果表明，在所有载荷条件下，随着纤维含量增加至20 wt.%，磨损率显著降低；在20、40和60 N载荷下，其最低磨损率分别达到1.2、2.1和3.9 ×10-4 mm³/Nm。当纤维含量超过20 wt.%时，磨损率开始增加，表明较高纤维含量导致纤维团聚及界面缺陷的产生。研究进一步建立了二次多项式回归模型，以预测纤维含量和载荷对磨损率的影响。模型分析及等值线图显示，最佳耐磨区域位于纤维含量约20 wt.%、载荷约35–45 N范围内。该组成具有优异耐磨性能，主要归因于纤维与基体之间更强的界面结合、更有效的应力传递以及更少的微观结构缺陷。研究结果表明，含20 wt.% OPF增强体的复合材料在中等载荷条件下具有最佳耐磨性能，可作为汽车和工业零部件等摩擦学应用的潜在候选材料。
Keywords: oil palm fronds; phenol formaldehyde; pin-on-disc tribometer; tribology; natural fiber composites
关键词：油棕榈叶柄；酚醛树脂；销盘式摩擦磨损试验机；摩擦学；天然纤维复合材料
How to Cite: Istana, B., Hasan, I., & Winangun, K. (2025). Influence of fiber content and applied load on the wear mechanisms of oil palm frond fiber/phenol-formaldehyde composites with functional fillers. Journal of Engineering Researcher and Lecturer, 4(3), 136–145. https://doi.org/10.58712/jerel.v4i3.198
Comparative static structural assessment of an energy-efficient prototype vehicle chassis using finite element analysis: AISI 1020 steel vs. 6061-T6 aluminum
基于有限元分析的节能原型车底盘静态结构性能比较：AISI 1020 钢与 6061-T6 铝合金
Muhammad Fadil Andira, Wanda Afnison, Waskito Waskito, Delima Yanti Sari
Department of Mechanical Engineering, Faculty of Engineering, Universitas Negeri Padang, Indonesia
DOI: https://doi.org/10.58712/jerel.v4i3.199
Abstract
This study evaluates the static structural performance of a Prototype-class energy-efficient vehicle chassis for the Indonesian Kontes Mobil Hemat Energi (KMHE; Energy-Efficient Car Competition) by comparing two material options, AISI 1020 carbon steel and Al 6061-T6, under a consistent load representation. Three-dimensional chassis models were developed in SolidWorks and assessed using static finite element analysis (FEA). The loading scenario included gravitational body force and two concentrated static loads representing operational conditions: 700 N applied at the driver seat region and 300 N applied at the engine mounting area. A curvature-based meshing strategy was adopted, with element sizes ranging from 1.6 to 8 mm, resulting in approximately 1,700,093 nodes to capture geometric details in joints and curved members. The AISI 1020 chassis produced a maximum von Mises stress of 278.6 MPa concentrated near the engine mounting joint, a maximum total deformation of 2.1 mm in the roll-bar region, and a minimum factor of safety of 1.3. In contrast, the Al 6061-T6 chassis exhibited a lower peak stress of 61 MPa at the rear wheel mounting region, a higher deformation of 3.4 mm at the roll bar, and a factor of safety of 4.5. The findings confirm a trade-off between stiffness and safety margin: steel offers higher stiffness but an insufficient safety margin, while aluminium significantly improves the static safety margin with increased deformation. These results provide design guidance for reinforcing critical regions and enhancing the robustness of competition-ready chassis.
摘要
本研究采用有限元分析（Finite Element Analysis，FEA），比较 AISI 1020 碳钢和 Al 6061-T6 铝合金两种材料在相同载荷条件下作为印度尼西亚节能汽车竞赛（Kontes Mobil Hemat Energi，KMHE）原型车底盘材料时的静态结构性能。研究利用 SolidWorks 建立三维底盘模型，并开展静态有限元分析。载荷工况包括重力载荷以及两个集中静载荷：驾驶员座椅区域施加700 N载荷，发动机安装区域施加300 N载荷。网格划分采用基于曲率的网格生成策略，单元尺寸范围为1.6–8 mm，共生成约1,700,093个节点，以准确捕捉连接部位及曲面构件的几何细节。结果表明，AISI 1020 钢底盘在发动机安装接头附近产生最大 von Mises 应力278.6 MPa，滚架区域最大总变形为2.1 mm，最小安全系数为1.3。相比之下，Al 6061-T6 铝合金底盘在后轮安装区域产生较低的最大应力61 MPa，但滚架区域最大变形增至3.4 mm，安全系数提高至4.5。研究结果表明，底盘刚度与安全裕度之间存在权衡关系：钢材具有更高的结构刚度，但安全裕度较低；而铝合金虽然变形较大，却显著提高了静态安全裕度。研究结果可为关键结构部位的强化设计及竞赛型节能汽车底盘结构优化提供重要参考。
Keywords: vehicle chassis; finite element analysis; von Mises stress; total deformation; lightweight structures
关键词：车辆底盘；有限元分析；von Mises 应力；总变形；轻量化结构
How to Cite: Andira, M. F., Afnison, W., Waskito, W., & Sari, D. Y. (2025). Comparative static structural assessment of an energy-efficient prototype vehicle chassis using finite element analysis: AISI 1020 steel vs. 6061-T6 aluminum. Journal of Engineering Researcher and Lecturer, 4(3), 146–158. https://doi.org/10.58712/jerel.v4i3.199
Simulation–adventure virtual worlds in the metaverse for engineering education and training: A domain-stratified narrative review
元宇宙中模拟–冒险虚拟世界在工程教育与培训中的应用：基于领域分类的叙述性综述
Aprilla Fortuna, Muhammad Raihan, Dimas Aulia Saputra, Juan Luis Cabanillas García, Firas Tayseer Ayasrah
Department of Mechanical Engineering, Faculty of Engineering, Universitas Negeri Padang, Indonesia
Master's in Vocational and Technology Education, Universitas Pendidikan Indonesia, Indonesia
Department of Didactics, Organization and Research Methods, Universidad de Extremadura, Spain
College of Education, Humanities and Science, Al Ain University, United Arab Emirates
DOI: https://doi.org/10.58712/jerel.v4i3.191
Abstract
This study employs a narrative review methodology to analyze the integration of Virtual Worlds, specifically Simulation Worlds and Adventure Worlds, in engineering education, aiming to enhance conceptual understanding, technical competence, and 21st-century skills. The study synthesizes 23 peer-reviewed articles selected from the Scopus database using stringent inclusion criteria. Simulation-based learning models focus on procedural accuracy and conceptual mastery, while adventure-based models emphasize transversal skills like creativity, collaboration, and problem-solving. Hybrid models combining both approaches are identified as the most effective, fostering technical expertise and soft skills simultaneously. Despite challenges such as high infrastructure costs and potential cognitive overload, immersive virtual environments offer significant opportunities for scalable and adaptable remote learning. Thematic analysis is employed to synthesize findings and provide recommendations for future implementation. This review highlights the importance of integrating these technologies in engineering education and suggests exploring their long-term impact on engineering careers. Additionally, it underscores the need for further research on the application of immersive technologies across diverse engineering disciplines, focusing on overcoming existing challenges and maximizing their educational potential.
摘要
本研究采用叙述性综述（Narrative Review）方法，分析虚拟世界（Virtual Worlds），特别是模拟世界（Simulation Worlds）和冒险世界（Adventure Worlds）在工程教育中的应用，旨在提升学习者的概念理解能力、专业技术能力以及21世纪核心技能。研究依据严格的纳入标准，从 Scopus 数据库筛选并综合分析了23篇同行评审文献。研究发现，基于模拟的学习模式侧重于程序执行的准确性和概念掌握，而基于冒险的学习模式则更加注重创造力、协作能力和问题解决能力等跨领域技能的培养。同时结合两种模式的混合学习模式被认为最具成效，能够同时促进专业技术能力和软技能的发展。尽管沉浸式虚拟环境仍面临基础设施建设成本高以及可能导致学习者认知负荷增加等挑战，但其在构建可扩展、适应性强的远程学习环境方面具有巨大潜力。研究采用主题分析法综合相关研究成果，并提出未来实施建议。本文强调，将虚拟世界技术融入工程教育具有重要意义，并建议进一步探讨其对工程专业人才长期职业发展的影响。此外，研究还指出，有必要进一步探索沉浸式技术在不同工程学科中的应用，以解决现有挑战并充分发挥其教育价值。
Keywords: metaverse; virtual worlds; engineering education; immersive learning; narrative review
关键词：元宇宙；虚拟世界；工程教育；沉浸式学习；叙述性综述
How to Cite: Fortuna, A., Raihan, M., Saputra, D. A., García, J. L. C., & Ayasrah, F. T. (2025). Simulation–adventure virtual worlds in the metaverse for engineering education and training: A domain-stratified narrative review. Journal of Engineering Researcher and Lecturer, 4(3), 159–182. https://doi.org/10.58712/jerel.v4i3.191
Experimental study on the use of wood pellet briquettes in rocket stoves for household energy needs
木颗粒压块燃料在火箭炉中满足家庭能源需求的实验研究
Rafki Irianto, Yolli Fernanda, Primawati Primawati, Dori Yuvenda
Department of Mechanical Engineering, Faculty of Engineering, Universitas Negeri Padang, Indonesia
DOI: https://doi.org/10.58712/jerel.v5i1.206
Abstract
This experimental study investigates the effect of air supply configurations on the combustion performance and thermal efficiency of wood pellet briquettes in rocket stoves for household energy use. With increasing global demand for energy and the depletion of fossil fuels, the shift to renewable biomass fuels, such as wood pellets, is essential to reduce carbon emissions and enhance energy efficiency. The study evaluates four airflow configurations: right fan only (F3), lower-left + right fans (F2+F3), two left fans (F1+F2), and all fans (F1+F2+F3). The results show that the F3 configuration achieved the fastest boiling time, highest boiling temperature, and lowest heat-loss temperature, indicating superior thermal performance. In contrast, configurations with higher airflow (F1+F2 and all fans) led to greater heat losses and slower boiling times, suggesting that excessive airflow can negatively affect efficiency. Additionally, the analysis of residual mass revealed that F3 and F2+F3 configurations produced the lowest residuals, indicating more complete combustion. This study provides important insights into optimising airflow configurations to improve the efficiency of biomass stoves. The findings offer practical implications for the design and operation of sustainable cooking technologies, promoting energy efficiency and reducing reliance on fossil fuels in households, particularly in rural areas.
摘要
本实验研究探讨了不同供风配置对火箭炉中木颗粒压块燃料燃烧性能和热效率的影响，以满足家庭能源需求。随着全球能源需求不断增长以及化石燃料日益枯竭，采用木颗粒等可再生生物质燃料对于减少碳排放和提高能源利用效率具有重要意义。本研究比较了四种供风配置：仅右侧风机（F3）、左下风机与右侧风机（F2+F3）、两个左侧风机（F1+F2）以及全部风机（F1+F2+F3）。研究结果表明，仅采用右侧风机（F3）时，沸腾时间最短、沸腾温度最高、热损失温度最低，表现出最佳的热性能。相比之下，供风量较大的配置（F1+F2 和 F1+F2+F3）产生了更大的热损失和更长的沸腾时间，说明过大的供风量会降低燃烧效率。此外，对燃烧残余物质量的分析表明，F3 和 F2+F3 配置产生的残余物最少，表明燃烧更加充分。本研究为优化供风配置、提高生物质炉具燃烧效率提供了重要参考。研究结果对可持续炊事技术的设计与运行具有实际指导意义，有助于提高能源利用效率，并减少家庭特别是农村地区对化石燃料的依赖。
Keywords: forced-draft air supply; thermal efficiency; combustion performance; biomass energy
关键词：强制送风；热效率；燃烧性能；生物质能源
How to Cite: Irianto, R., Fernanda, Y., Primawati, P., & Yuvenda, D. (2026). Experimental study on the use of wood pellet briquettes in rocket stoves for household energy needs. Journal of Engineering Researcher and Lecturer, 5(1), 1–15. https://doi.org/10.58712/jerel.v5i1.206
A literature review of ecosystem-based strategies to reduce public building vulnerability to earthquakes: A case study of Tarakan City
基于生态系统策略降低公共建筑地震脆弱性的文献综述：以塔拉坎市为例
Eko Prihartanto, Widyo Nugroho, Budi Setiawan
Department of Civil Engineering, Faculty of Engineering, Universitas Borneo Tarakan, Indonesia
Department of Civil Engineering, Faculty of Science and Engineering, Universitas Bojonegoro, Indonesia
Department of Civil Engineering, Faculty of Engineering, Universitas Borneo Tarakan, Indonesia
DOI: https://doi.org/10.58712/jerel.v5i1.203
Abstract
Tarakan City, an archipelagic region in Indonesia, exhibits a high level of vulnerability to earthquake disasters, particularly regarding public infrastructure that has not been fully designed using seismic resilience approaches. Public buildings such as schools, hospitals, and government offices play a vital role in supporting social functions and basic services, making their earthquake resilience highly crucial. This study aims to identify and analyze ecosystem-based strategies that can be employed to reduce the vulnerability of public buildings to earthquakes. Through a systematic literature review method, this research examines various approaches involving technical, social, institutional, and environmental aspects in building infrastructure resilience. The results indicate that the integration of earthquake-resistant building design, community participation, risk-based spatial planning policies, early warning systems, and institutional capacity building forms an effective and sustainable resilience ecosystem. The contextual analysis of Tarakan City suggests the need for synergy between local government, the community, and the technical sector to strengthen the adaptive capacity of public infrastructure, particularly within the context of archipelagic regions facing logistical and resource constraints. This study provides a conceptual framework that can serve as a basis for developing resilient ecosystem-based mitigation policies for earthquake-prone areas.
摘要
印度尼西亚群岛城市塔拉坎（Tarakan）面临较高的地震灾害风险，尤其是部分公共基础设施尚未充分采用抗震韧性设计理念，使其地震脆弱性更加突出。学校、医院和政府办公楼等公共建筑承担着社会服务和公共职能，其抗震能力对于保障社会正常运行至关重要。本研究旨在识别并分析可用于降低公共建筑地震脆弱性的生态系统策略。采用系统性文献综述（Systematic Literature Review）方法，研究综合分析了提升基础设施韧性的多种技术、社会、制度及环境策略。研究结果表明，将抗震建筑设计、社区参与、基于风险的空间规划政策、地震预警系统以及制度能力建设相结合，可构建高效且可持续的韧性生态系统。结合塔拉坎市的实际情况分析发现，在物流和资源受限的群岛地区，应加强地方政府、社区和技术部门之间的协同合作，以提升公共基础设施的适应能力。本研究提出了一个概念性框架，可为地震易发地区制定基于生态系统的韧性减灾政策提供理论依据。
Keywords: ecosystem; earthquake; infrastructure; resilience
关键词：生态系统；地震；基础设施；韧性
How to Cite: Prihartanto, E., Nugroho, W., & Setiawan, B. (2026). A literature review of ecosystem-based strategies to reduce public building vulnerability to earthquakes: A case study of Tarakan City. Journal of Engineering Researcher and Lecturer, 5(1), 16–29. https://doi.org/10.58712/jerel.v5i1.203
Numerical and experimental performance evaluation of an Eppler 420–based horizontal-axis hydrokinetic turbine for low-velocity river applications
基于 Eppler 420 翼型的水平轴水动力涡轮机在低流速河流中的数值与实验性能评估
Ma. Leona Maye B. Pepito
Department of Mechanical Engineering, University of Science and Technology of Southern Philippines, Philippines
DOI: https://doi.org/10.58712/jerel.v5i1.202
Abstract
Small-scale hydrokinetic turbines offer a viable solution for harnessing renewable energy from low-velocity rivers and canals, particularly in developing countries such as the Philippines, where a large portion of hydropower potential remains untapped. However, limited studies have experimentally validated the performance of airfoil-based propeller hydrokinetic turbines optimized for shallow, low-speed water streams. This study addresses this gap by designing, simulating, fabricating, and experimentally evaluating a horizontal-axis propeller hydrokinetic turbine based on the Eppler 420 airfoil. A combined Computational Fluid Dynamics (CFD) and field-testing approach was employed to optimize blade geometry, tip speed ratio, and diffuser configuration for a turbine with a swept area of 0.18 m² operating at stream velocities of 0.7–1.3 m/s. CFD results indicate that the venturi-type diffuser increased the inlet water velocity by an average of 62%, resulting in a simulated shaft power increase from 56 W for the bare turbine to 70 W for the diffuser-augmented configuration. Field experiments conducted in a local river validated these trends, achieving a maximum measured shaft power of 65 W at 1.3 m/s with a corresponding power coefficient of approximately 0.30. The close agreement between simulated and experimental results confirms the suitability of the Eppler 420 airfoil for low-velocity hydrokinetic applications and demonstrates the effectiveness of diffuser augmentation. The findings provide practical design guidance and experimental validation for efficient small-scale hydrokinetic turbine deployment in shallow inland water streams.
摘要
小型水动力涡轮机（hydrokinetic turbine）为开发低流速河流和运河中的可再生能源提供了一种可行方案，尤其适用于菲律宾等大量水电资源尚未得到充分开发的发展中国家。然而，目前针对浅水、低流速水体优化的翼型螺旋桨式水动力涡轮机，其性能实验验证研究仍然有限。本研究针对这一研究空白，设计、仿真、制造并实验评估了一种基于 Eppler 420 翼型的水平轴螺旋桨式水动力涡轮机。研究采用计算流体力学（Computational Fluid Dynamics，CFD）与现场试验相结合的方法，对叶片几何形状、叶尖速比（tip speed ratio）及扩散器（diffuser）结构进行了优化。该涡轮机扫掠面积为0.18 m²，适用于0.7–1.3 m/s的水流速度范围。CFD 仿真结果表明，文丘里型扩散器使入口水流速度平均提高62%，从而使模拟轴功率由无扩散器时的56 W提高至采用扩散器后的70 W。随后在当地河流开展的现场实验验证了上述结果，在1.3 m/s流速条件下测得最大轴功率为65 W，相应功率系数约为0.30。数值模拟与实验结果之间具有良好的一致性，证明 Eppler 420 翼型适用于低流速水动力发电应用，同时验证了扩散器增效技术的有效性。本研究为浅水内陆河流水动力涡轮机的高效设计、优化及实际应用提供了重要的实验依据和工程设计参考。
Keywords: renewable energy; hydrokinetic turbine; Eppler 420; diffuser-augmented
关键词：可再生能源；水动力涡轮机；Eppler 420；扩散器增效
How to Cite: Pepito, M. L. M. B. (2026). Numerical and experimental performance evaluation of an Eppler 420–based horizontal-axis hydrokinetic turbine for low-velocity river applications. Journal of Engineering Researcher and Lecturer, 5(1), 30–43. https://doi.org/10.58712/jerel.v5i1.202
3D scanner technology in the reverse engineering of complex mechanical components: A literature review
复杂机械零部件逆向工程中的三维扫描技术：文献综述
Afferli Seftian, Delima Yanti Sari, Rifelino Rifelino, Zainal Abadi
Department of Mechanical Engineering, Faculty of Engineering, Universitas Negeri Padang, Indonesia
Abstract
This study addresses the challenges involved in the reverse engineering of complex mechanical components, where conventional manual measurement methods often produce geometric deviations that negatively affect the reliability of advanced engineering analyses. A descriptive literature review was conducted to evaluate the role of 3D scanning technology in overcoming these limitations. The study compares various data acquisition methods, including laser scanning, structured light scanning, and photogrammetry, while also analysing how the level of geometric accuracy influences finite element simulation results and structural analysis outcomes. The review found that 3D scanning significantly improves geometric fidelity compared with traditional techniques, thereby enhancing the validity of numerical simulations. However, the review also identified that the quality of the final model is highly dependent on the selected scanning technology, surface conditions, and advanced reconstruction processes such as point cloud registration and mesh generation. The findings indicate that although 3D scanning offers superior precision, geometric deviations may still occur and influence structural parameters. This study concludes that the integration of 3D scanning into reverse engineering workflows requires systematic validation to ensure not only visual accuracy but also functional reliability in engineering applications. Furthermore, this review highlights a critical research gap, suggesting that future studies should place greater emphasis on the direct correlation between geometric accuracy and engineering simulation outcomes.
摘要
本研究针对复杂机械零部件逆向工程过程中所面临的挑战展开讨论，其中传统人工测量方法常产生几何偏差，从而降低先进工程分析结果的可靠性。研究采用描述性文献综述方法，评估三维扫描（3D Scanning）技术在克服上述局限性方面的作用。本文比较了多种数据采集方法，包括激光扫描（Laser Scanning）、结构光扫描（Structured Light Scanning）和摄影测量（Photogrammetry），同时分析几何精度水平对有限元仿真（Finite Element Simulation）结果及结构分析性能的影响。文献综述结果表明，与传统测量技术相比，三维扫描技术能够显著提高几何保真度，从而增强数值模拟结果的有效性。然而，研究同时指出，最终模型的质量高度依赖于所采用的扫描技术、工件表面条件以及点云配准（Point Cloud Registration）和网格生成（Mesh Generation）等高级重建过程。研究结果表明，尽管三维扫描具有较高的测量精度，但几何偏差仍可能存在，并对结构分析参数产生影响。因此，本研究认为，将三维扫描技术应用于逆向工程流程时，需要进行系统性的验证，以确保模型不仅具有较高的几何精度，而且能够满足工程应用中的功能可靠性要求。此外，本综述还指出了当前研究中的一个重要空白，即未来研究应更加关注几何精度与工程仿真结果之间的直接关联。
Keywords: 3D scanning; geometric accuracy; modal analysis; reverse engineering
关键词：三维扫描；几何精度；模态分析；逆向工程
How to Cite: Seftian, A., Sari, D. Y., Rifelino, R., & Abadi, Z. (2026). 3D scanner technology in the reverse engineering of complex mechanical components: A literature review. Journal of Engineering Researcher and Lecturer, 5(1), 44–62. https://doi.org/10.58712/jerel.v5i1.213
Adhesion mechanisms and mechanical performance of single-lap joints in FDM-3D printed: A review
FDM 三维打印单搭接接头的粘接机制与力学性能：综述
Muhamad Qeisya Hanif, Rifelino Rifelino, Febri Prasetya, Zainal Abadi
Department of Mechanical Engineering, Faculty of Engineering, Universitas Negeri Padang, Indonesia
DOI: https://doi.org/10.58712/jerel.v5i1.214
Abstract
Additive Manufacturing (AM), particularly Fused Deposition Modeling (FDM), has evolved from a rapid prototyping technology into a manufacturing approach for producing functional components across a wide range of industrial sectors. Nevertheless, the limited build volume of FDM systems has encouraged the use of adhesive bonding as a practical method for joining sub-components, with the single-lap joint (SLJ) configuration being among the most widely adopted designs. This review aims to provide an integrated analysis of the relationship between FDM-induced surface morphology, the adhesion mechanisms developed at the bonded interface, and their implications for stress distribution, shear strength, and joint failure modes. The findings indicate that the surface characteristics generated by the FDM process, including layer lines, stair-stepping effects, voids, and porosity, create interfacial conditions that differ fundamentally from those of homogeneous materials. These characteristics also produce a non-linear relationship between surface roughness and joint strength. Process parameters such as printing orientation and layer height were identified as key controlling factors that influence surface topography and adhesive performance. From a mechanical perspective, the eccentric load path inherent in SLJ configurations generates significant shear and peel stress concentrations at the overlap ends. These stress concentrations coincide with structurally weak regions that are intrinsically associated with FDM adherends, making them the primary sites for crack initiation and joint failure. Furthermore, modifications to overlap geometry and tailored adhesive distribution have been recognized as effective strategies for improving stress redistribution and enhancing the load-bearing capacity of the joint. This review highlights that the assessment of adhesive joints in FDM-manufactured components requires an integrated analytical framework that accounts for the coupled interactions among printing process parameters, surface conditions, adhesive properties, and progressive failure modeling. Such an approach is essential for the development of reliable structural joint designs for FDM-based applications.
摘要
增材制造（Additive Manufacturing，AM），特别是熔融沉积成型（Fused Deposition Modeling，FDM），已从快速原型制造技术发展成为适用于多个工业领域功能性零部件制造的重要制造方法。然而，由于 FDM 系统成形尺寸受限，胶粘连接（adhesive bonding）已成为连接多个子部件的实用方案，其中单搭接接头（Single-Lap Joint，SLJ）是应用最广泛的连接结构之一。本文综述旨在综合分析 FDM 成形表面形貌、粘接界面形成的粘附机制及其对接头应力分布、剪切强度和失效模式的影响。研究结果表明，FDM 工艺形成的层纹（layer lines）、台阶效应（stair-stepping effect）、孔隙（voids）和多孔结构（porosity）等表面特征，使粘接界面与均质材料存在本质差异，并导致表面粗糙度与接头强度之间呈现非线性关系。打印方向和层厚等工艺参数被认为是影响表面形貌及胶粘性能的关键因素。从力学角度来看，SLJ 结构固有的偏心载荷路径会在搭接端部产生显著的剪切应力和剥离应力集中，而这些区域通常也是 FDM 打印基材结构最薄弱的位置，因此成为裂纹萌生和接头失效的主要区域。此外，优化搭接几何形状及合理设计胶层分布已被证明能够有效改善应力重新分布，并提高接头承载能力。本文强调，对 FDM 制造构件胶粘接头性能的评估，应建立综合分析框架，同时考虑打印工艺参数、表面状态、胶粘剂性能及渐进失效模型之间的耦合作用。该研究框架对于开发适用于 FDM 制造结构件的高可靠性胶粘接头设计具有重要意义。
Keywords: adhesive bonding; additive manufacturing; fused deposition modeling; interlayer bonding
关键词：胶粘连接；增材制造；熔融沉积成型；层间结合
How to Cite: Hanif, M. Q., Rifelino, R., Prasetya, F., & Abadi, Z. (2026). Adhesion mechanisms and mechanical performance of single-lap joints in FDM-3D printed: A review. Journal of Engineering Researcher and Lecturer, 5(1), 63–80. https://doi.org/10.58712/jerel.v5i1.214
Post-weld heat treatment of GTAW-repaired aluminium 6061-T6 calliper brackets: Effects on surface integrity and micro Vickers hardness
GTAW 修复的 6061-T6 铝合金制动卡钳支架焊后热处理：对表面完整性与显微维氏硬度的影响
Dipo Ariyo Nugroho, Zainal Abadi, Rifelino Rifelino, Andril Arafat
Department of Mechanical Engineering, Faculty of Engineering, Universitas Negeri Padang, Indonesia
DOI: https://doi.org/10.58712/jerel.v5i2.218
Abstract
The caliper bracket is a critical component of a motorcycle braking system that maintains the alignment between the brake caliper and the rotor. Repair of damaged caliper brackets is commonly carried out using the Gas Tungsten Arc Welding (GTAW) process. However, the thermal cycle during welding may alter the microstructure and degrade the mechanical properties of Aluminum 6061-T6. To overcome this limitation, post-weld heat treatment (PWHT), in accordance with ASTM B918, can be applied to restore the material properties and enhance the quality of the welded joint. This study investigates the effect of PWHT on the surface quality and microhardness of Aluminum 6061-T6 caliper brackets repaired using the GTAW process. An experimental approach was employed in which all specimens were welded using identical welding parameters and subsequently subjected to PWHT consisting of solution heat treatment, quenching, and artificial aging. Surface quality was evaluated through liquid penetrant testing in accordance with ASTM E165, while microhardness was measured using the Micro Vickers hardness test based on ASTM E384. The penetrant test results revealed that the welded specimens before PWHT contained welding defects, including porosity, lack of fusion, and lack of penetration, with a total of 35 defect indications. After PWHT, the number of defect indications decreased to 19, consisting only of microscopic porosity and lack of fusion. The average microhardness increased from 67.34 HV to 92.26 HV in the Fusion Zone (FZ), from 69.66 HV to 97.78 HV in the Heat-Affected Zone (HAZ), and from 62.44 HV to 95.70 HV in the Base Metal (BM), corresponding to increases of 45.66%, 40.49%, and 53.27%, respectively. Furthermore, PWHT restored the material hardness to 91.62% of the raw material hardness (103.96 HV). These findings demonstrate that PWHT effectively improves both the mechanical performance and the overall quality of GTAW-repaired Aluminum 6061-T6 caliper brackets.
摘要
制动卡钳支架（caliper bracket）是摩托车制动系统中的关键部件，其作用是保持制动卡钳与制动盘之间的正确对中。受损的卡钳支架通常采用钨极惰性气体保护焊（Gas Tungsten Arc Welding，GTAW）进行修复。然而，焊接过程中的热循环会改变 6061-T6 铝合金的显微组织，并降低其力学性能。为克服这一问题，可依据 ASTM B918 标准实施焊后热处理（Post-Weld Heat Treatment，PWHT），以恢复材料性能并提高焊接接头质量。本研究旨在探讨 PWHT 对采用 GTAW 修复的 6061-T6 铝合金卡钳支架表面质量及显微硬度的影响。研究采用实验方法，所有试样均在相同焊接参数下完成 GTAW 焊接，随后依次进行固溶处理、淬火和人工时效等 PWHT 工艺。表面质量依据 ASTM E165 标准采用液体渗透检测（Liquid Penetrant Testing）进行评估，显微硬度则依据 ASTM E384 标准采用显微维氏硬度试验（Micro Vickers Hardness Test）测定。渗透检测结果表明，PWHT 前焊接试样共发现35处缺陷，包括气孔（porosity）、未熔合（lack of fusion）和未焊透（lack of penetration）。经过 PWHT 后，缺陷数量减少至19处，仅保留微小气孔和未熔合缺陷。显微维氏硬度平均值在熔合区（Fusion Zone，FZ）由67.34 HV提高至92.26 HV，在热影响区（Heat-Affected Zone，HAZ）由69.66 HV提高至97.78 HV，在母材区（Base Metal，BM）由62.44 HV提高至95.70 HV，分别提高45.66%、40.49%和53.27%。此外，PWHT 后材料硬度恢复至原始母材硬度（103.96 HV）的91.62%。研究结果表明，焊后热处理能够有效改善 GTAW 修复的 6061-T6 铝合金卡钳支架的力学性能和整体焊接质量。
Keywords: Aluminium 6061-T6; Calliper Bracket; GTAW; Micro Vickers Hardness; Penetrant Testing; Post-Weld Heat Treatment
关键词：6061-T6 铝合金；制动卡钳支架；GTAW；显微维氏硬度；渗透检测；焊后热处理
How to Cite: Nugroho, D. A., Abadi, Z., Rifelino, R., & Arafat, A. (2026). Post-weld heat treatment of GTAW-repaired aluminium 6061-T6 calliper brackets: Effects on surface integrity and micro Vickers hardness. Journal of Engineering Researcher and Lecturer, 5(2), 81–98. https://doi.org/10.58712/jerel.v5i2.218
Finite element analysis and crashworthiness evaluation of a multi-stage aluminium alloy 6061-T6 impact attenuator for Formula SAE
用于 Formula SAE 多级 6061-T6 铝合金碰撞吸能器的有限元分析与耐撞性能评估
Aditia Pratama, Zainal Abadi, Delima Yanti Sari, Wanda Afnison
Department of Mechanical Engineering, Faculty of Engineering, Universitas Negeri Padang, Indonesia
DOI: https://doi.org/10.58712/jerel.v5i2.219
Abstract
Formula SAE regulations require every prototype vehicle to be equipped with an impact attenuator as a passive safety system capable of absorbing a minimum frontal impact energy of 7,350 J at an impact velocity of 7 m/s for a vehicle with a mass of approximately 300 kg. This study aims to design an impact attenuator that satisfies the Formula SAE requirements to improve vehicle crashworthiness. Three design variations were analyzed using Finite Element Analysis (FEA) with LS-DYNA to evaluate energy absorption, impact force, acceleration/deceleration, and displacement. The accuracy of the numerical model was validated using previously published experimental data before analyzing the effect of thickness variation in each stage of the impact attenuator. The simulation results show that the optimum design is capable of absorbing impact energy above the minimum requirement of 7,350 J, exhibits a high Crash Force Efficiency (CFE), produces acceleration within the prescribed safety limits, and provides controlled deformation during the impact process. The results indicate that the proposed impact attenuator design satisfies the Formula SAE safety requirements and has the potential to be applied to prototype vehicles to improve safety performance during frontal collisions.
摘要
Formula SAE 竞赛规则要求所有原型赛车均配备碰撞吸能器（Impact Attenuator）作为被动安全系统，以确保质量约300 kg的车辆在7 m/s正面碰撞速度下能够吸收至少7,350 J的碰撞能量。本研究旨在设计一种满足 Formula SAE 技术规范要求的碰撞吸能器，以提高车辆的耐撞性能（Crashworthiness）。研究采用 LS-DYNA 有限元分析（Finite Element Analysis，FEA）对三种不同设计方案进行了数值模拟，评估其能量吸收能力、碰撞载荷、加速度/减速度以及位移响应。数值模型首先依据已发表的实验数据进行了验证，随后分析了碰撞吸能器各级结构厚度变化对其性能的影响。模拟结果表明，优化后的设计能够吸收超过7,350 J的碰撞能量，具有较高的碰撞力效率（Crash Force Efficiency，CFE），产生的加速度满足安全规范要求，并在碰撞过程中实现可控变形。研究结果表明，所提出的多级6061-T6铝合金碰撞吸能器设计符合 Formula SAE 的安全要求，具有应用于原型赛车以提升正面碰撞安全性能的潜力。
Keywords: AA6061-T6 aluminium alloy; Crashworthiness; Energy absorption; Finite Element Analysis (FEA); Formula SAE; Impact attenuator
关键词：AA6061-T6 铝合金；耐撞性能；能量吸收；有限元分析（FEA）；Formula SAE；碰撞吸能器
How to Cite: Pratama, A., Abadi, Z., Sari, D. Y., & Afnison, W. (2026). Finite element analysis and crashworthiness evaluation of a multi-stage aluminium alloy 6061-T6 impact attenuator for Formula SAE. Journal of Engineering Researcher and Lecturer, 5(2), 95–109. https://doi.org/10.58712/jerel.v5i2.219
Mechanical characteristics and FEA-based non-uniform infill density approaches for Fused Deposition Modelling (FDM)-printed components: A literature review
熔融沉积成型（FDM）打印构件的力学特性及基于有限元分析的非均匀填充密度方法：文献综述
Mhd. Fahri Meihanda Putra, Syahril Syahril, Delima Yanti Sari
Department of Mechanical Engineering, Faculty of Engineering, Universitas Negeri Padang, Indonesia
DOI: https://doi.org/10.58712/jerel.v5i2.220
Abstract
Fused Deposition Modelling (FDM) is one of the most widely used additive manufacturing (AM) technologies for producing functional polymer components. However, commercially available slicing software generally applies a uniform infill density throughout the entire component without considering the actual stress distribution, resulting in excessive material usage in low-stress regions and unnecessary increases in component weight. This literature review synthesizes current knowledge on the mechanical characteristics of FDM-printed components and evaluates Finite Element Analysis (FEA)-based non-uniform infill density approaches as a promising strategy for structural optimization. The reviewed literature covers the effects of anisotropic behaviour, internal voids, infill density, infill pattern, and the integration of FEA with topology optimization techniques for FDM components. The findings indicate that the layer-by-layer deposition process produces pronounced mechanical anisotropy and introduces internal voids that influence structural performance. The relationship between infill density and mechanical strength is positive but nonlinear, whereas different infill patterns at the same density can produce variations of up to 82% in flexural strength. Although FEA provides reliable estimates of stress distribution, prediction errors of approximately 8.67–12% remain because conventional simulations assume homogeneous and isotropic materials that do not accurately represent the actual characteristics of FDM-printed components. Furthermore, FEA-based multi-zone non-uniform infill density strategies have been reported to increase peak load by up to 49% and bending stiffness by up to 46% compared with conventional uniform-density configurations. Overall, this review demonstrates that FEA-based non-uniform infill density is a promising design optimization strategy for functional FDM-printed components by improving structural performance while reducing unnecessary material usage. Future research should focus on density transition design and experimental validation to improve the reliability and practical implementation of this approach.
摘要
熔融沉积成型（Fused Deposition Modelling，FDM）是应用最广泛的增材制造（Additive Manufacturing，AM）技术之一，可用于制造功能性聚合物构件。然而，目前商业切片软件通常在整个构件中采用均匀填充密度（uniform infill density），而未考虑实际应力分布，导致低应力区域材料使用过量，并造成构件重量不必要的增加。本文通过文献综述综合分析了 FDM 打印构件的力学特性，并评估了基于有限元分析（Finite Element Analysis，FEA）的非均匀填充密度方法作为结构优化策略的应用潜力。综述内容涵盖了各向异性行为、内部孔隙、填充密度、填充图案以及 FEA 与拓扑优化技术相结合在 FDM 构件中的应用。研究结果表明，逐层沉积制造工艺会产生显著的力学各向异性，并形成内部孔隙，从而影响构件的整体结构性能。填充密度与力学强度之间呈正相关但具有非线性关系，而在相同填充密度下，不同填充图案可导致弯曲强度最高相差82%。尽管 FEA 能够较准确地预测应力分布，但由于传统仿真通常假设材料均质且各向同性，与 FDM 打印构件的实际材料特性存在差异，因此预测误差仍约为8.67%–12%。此外，文献表明，基于 FEA 的多区域非均匀填充密度策略相比传统均匀填充结构，可使峰值载荷提高约49%，弯曲刚度提高约46%。总体而言，本综述认为，基于 FEA 的非均匀填充密度是一种具有广阔应用前景的 FDM 功能构件设计优化策略，可在减少材料消耗的同时显著提高结构性能。未来研究应重点关注填充密度过渡设计及实验验证，以进一步提高该方法的可靠性和工程应用可行性。
Keywords: additive manufacturing; fused deposition modelling; finite element analysis; non-uniform infill density; topology optimization; anisotropy
关键词：增材制造；熔融沉积成型；有限元分析；非均匀填充密度；拓扑优化；各向异性
How to Cite: Putra, M. F. M., Syahril, S., & Sari, D. Y. (2026). Mechanical characteristics and FEA-based non-uniform infill density approaches for Fused Deposition Modelling (FDM)-printed components: A literature review. Journal of Engineering Researcher and Lecturer, 5(2), 110–123. https://doi.org/10.58712/jerel.v5i2.220
```
System dynamics for integrated domestic wastewater management: A review of stock–flow models, policy scenarios, and river water quality
综合生活污水管理的系统动力学：存量–流量模型、政策情景与河流水质综述
Widia Putri, Denny Helard, Shinta Indah
Department of Environmental Engineering, Faculty of Engineering, Universitas Andalas, Indonesia
DOI: https://doi.org/10.58712/jerel.v5i2.221
Abstract
Domestic wastewater management is a long-term systems problem shaped by population growth, water use, sanitation coverage, treatment capacity, infrastructure deterioration, institutional performance, finance, pollutant generation, and receiving-water conditions. This review synthesizes the use of System Dynamics (SD) for integrated domestic wastewater planning, with emphasis on causal-loop structures, stock–flow models, policy scenarios, pollutant-load estimation, and river-water-quality responses. A structured narrative search covering 2010 to June 2026 was used to identify peer-reviewed studies that applied explicit SD concepts to wastewater, sanitation, water pollution, or coupled water-quality management. The literature shows that most models represent population, wastewater generation, treatment capacity, and pollution control, but fewer integrate on-site sanitation, faecal-sludge pathways, microbiological pollutants, river hydrology, climate stress, finance, and institutional behavior in one model. Scenario analysis is widely used, particularly business-as-usual, capacity expansion, service-coverage improvement, treatment-efficiency enhancement, and combined-policy scenarios. The evidence indicates that isolated infrastructure expansion often underperforms when household connections, operation and maintenance, financing, or treatment efficiency remain constrained. More robust models combine service coverage and capacity dynamics with pollutant mass balance, receiving-water dilution, validation tests, and sensitivity or uncertainty analysis. Coastal and data-limited cities require additional representation of shallow groundwater, infiltration and inflow, flooding, tidal backwater, sea-level rise, and the dominance of on-site sanitation. The review proposes an integrated framework linking socio-demographic, service, infrastructure, treatment, pollutant, river-quality, financial, institutional, and climate subsystems. Future development should prioritize spatial SD, participatory modelling, global sensitivity analysis, adaptive policy pathways, real-time monitoring, and hybridization with GIS, hydrological models, optimization, and machine learning.
摘要
生活污水管理是一个长期性的系统问题，其发展受到人口增长、用水需求、卫生服务覆盖率、污水处理能力、基础设施老化、机构绩效、资金投入、污染物产生以及受纳水体状况等多种因素的共同影响。本文综述了系统动力学（System Dynamics，SD）在综合生活污水管理规划中的应用，重点分析因果回路结构（causal-loop structures）、存量–流量模型（stock–flow models）、政策情景分析、污染负荷估算以及河流水质响应等方面的研究进展。研究采用结构化叙述性文献检索方法，对2010年至2026年6月期间发表的同行评议文献进行筛选，纳入明确应用系统动力学概念于污水处理、环境卫生、水污染控制或耦合水质管理的相关研究。文献表明，大多数模型涵盖人口增长、污水产生、处理能力和污染控制等核心要素，但较少有研究能够在同一模型中整合分散式卫生设施、粪污处理路径、微生物污染物、河流水文过程、气候压力、资金机制及制度行为等因素。政策情景分析被广泛采用，其中包括维持现状（business-as-usual）、处理能力扩展、服务覆盖率提升、处理效率提高以及综合政策组合等情景。研究证据表明，当居民接管率、运行维护、资金保障或处理效率受到限制时，仅依靠基础设施扩建往往难以取得理想效果。更具稳健性的模型通常结合服务覆盖率、处理能力动态、污染物质量平衡、受纳水体稀释过程、模型验证以及敏感性或不确定性分析。对于沿海地区及数据有限的城市，还需进一步考虑浅层地下水、渗入与入流、城市内涝、潮汐顶托、海平面上升以及分散式卫生设施占主导等特殊因素。本文提出了一个综合分析框架，将社会人口、公共服务、基础设施、污水处理、污染物、河流水质、财政、制度及气候等多个子系统进行有机整合。未来研究应重点发展空间系统动力学、参与式建模、全局敏感性分析、自适应政策路径、实时监测，以及与 GIS、水文模型、优化算法和机器学习等方法的融合应用。
Keywords: system dynamics; domestic wastewater; stock–flow model; policy scenarios; river water quality; urban sanitation
关键词：系统动力学；生活污水；存量–流量模型；政策情景；河流水质；城市环境卫生
How to Cite: Putri, W., Helard, D., & Indah, S. (2026). System dynamics for integrated domestic wastewater management: A review of stock–flow models, policy scenarios, and river water quality. Journal of Engineering Researcher and Lecturer, 5(2), 124–156. https://doi.org/10.58712/jerel.v5i2.221
```
Assessment of floating marine debris density, composition, chemical characteristics, and recycling potential along Gajah Beach and Pasir Putih Tabing Beach, Padang City, Indonesia
印度尼西亚巴东市 Gajah 海滩与 Pasir Putih Tabing 海滩漂浮海洋垃圾密度、组成、化学特性及回收潜力评估
Rizki Aziz, Budhi Primasari, Hirzan Salda Putra, Cici Amelia Edriani
Department of Environmental Engineering, Faculty of Engineering, Universitas Andalas, Indonesia
DOI: https://doi.org/10.58712/jerel.v5i2.222
Abstract
Floating marine debris is one of the major environmental challenges affecting coastal ecosystems and marine activities. Accumulation of floating debris can interfere with fishing operations by increasing the amount of debris captured in fishing nets and reducing fishing efficiency. This study evaluated the density, composition, chemical characteristics, and recycling potential of floating marine debris along Gajah Beach and Pasir Putih Tabing Beach, Padang City, Indonesia. Floating marine debris was collected using fishing trawls under two environmental conditions: normal weather and one day after a rainfall event. Samples were collected from three sampling points representing the study area and analyzed for debris density, material composition, proximate characteristics, and recycling potential. The average debris density increased from 1.18 g/m² under normal weather conditions to 3.13 g/m² after rainfall. Five material categories were identified, namely plastic, wood, rubber, fabric, and coconut husk. Plastic was the dominant material, accounting for 90% of the debris under normal weather conditions and 50% after rainfall, with corresponding densities of 0.90 g/m² and 1.66 g/m², respectively. Proximate analysis showed average values of 25.05% moisture content, 56.33% volatile matter, 8.53% ash content, and 9.09% fixed carbon. The results also indicate that plastic, wood, fabric, and coconut husk have potential for recycling or resource recovery. These findings provide baseline information for marine debris monitoring and support the development of more effective coastal waste management and resource recovery strategies in Padang City.
摘要
漂浮海洋垃圾（Floating Marine Debris）是影响沿海生态系统和海洋活动的主要环境问题之一。漂浮垃圾的累积不仅增加渔网中夹带杂物的数量，还会降低捕鱼效率，从而影响渔业生产。本研究对印度尼西亚巴东市 Gajah 海滩和 Pasir Putih Tabing 海滩漂浮海洋垃圾的密度、组成、化学特性及回收潜力进行了评估。在两种环境条件下开展采样，即正常天气条件和降雨后一天，采用渔船拖网（fishing trawls）收集漂浮海洋垃圾样品。研究在代表研究区域的三个采样点进行采样，并对垃圾密度、材料组成、工业分析特性（proximate characteristics）及资源回收潜力进行了分析。结果表明，漂浮垃圾平均密度由正常天气条件下的1.18 g/m²增加至降雨后的3.13 g/m²。共识别出五类主要材料，包括塑料、木材、橡胶、织物和椰壳。其中，塑料为占比最高的垃圾类型，在正常天气和降雨后分别占垃圾总量的90%和50%，对应密度分别为0.90 g/m²和1.66 g/m²。工业分析结果显示，样品平均含水率为25.05%，挥发分为56.33%，灰分为8.53%，固定碳为9.09%。研究进一步表明，塑料、木材、织物和椰壳均具有资源回收或再利用潜力。本研究为海洋垃圾监测提供了基础数据，并为巴东市制定更加有效的沿海固体废弃物管理和资源回收策略提供了科学依据。
Keywords: floating marine debris; debris density; marine debris composition; chemical characteristics; recycling potential; coastal waste management
关键词：漂浮海洋垃圾；垃圾密度；海洋垃圾组成；化学特性；回收潜力；沿海废弃物管理
How to Cite: Aziz, R., Primasari, B., Putra, H. S., & Edriani, C. A. (2026). Assessment of floating marine debris density, composition, chemical characteristics, and recycling potential along Gajah Beach and Pasir Putih Tabing Beach, Padang City, Indonesia. Journal of Engineering Researcher and Lecturer, 5(2), 157–171. https://doi.org/10.58712/jerel.v5i2.222
