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Eng. Proc., 2025, MEST 2024

The 8th Mechanical Engineering, Science and Technology International Conference

Perlis, Malaysia | 11–12 December 2024 

Volume Editors:
Noor Hanita Abdul Majid, Universiti Muhammadiyah Malaysia (UMAM), Malaysia
Agus Dwi Anggono, Universitas Muhammadiyah Surakarta (UMS), Indonesia
Waluyo Adi Siswanto, Universiti Muhammadiyah Malaysia (UMAM), Malaysia
Tri Widodo Besar Riyadi, Universitas Muhammadiyah Surakarta (UMS), Indonesia
Mohammad Sukri Mustapa, Universiti Tun Hussein Onn Malaysia (UTHM), Malaysia
Nur Rahmawati Syamsiyah, Universitas Muhammadiyah Surakarta (UMS), Indonesia
Afif Faishal, Universitas Muhammadiyah Surakarta (UMS), Indonesia

Number of Papers: 24
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Cover Story (view full-size image): The 8th Mechanical Engineering, Science, and Technology Conference (MEST 2024) is hosted by the Institute of Strategic Science and Technology (ITSaT), Universiti Muhammadiyah Malaysia (UMAM), which [...] Read more.
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2 pages, 134 KiB  
Editorial
Preface of the 8th Mechanical Engineering, Science and Technology International Conference (MEST 2024)
by Noor Hanita Abdul Majid, Agus Dwi Anggono, Waluyo Adi Siswanto, Tri Widodo Besar Riyadi, Nur Rahmawati Syamsiyah, Afif Faishal and Mohammad Sukri Mustapa
Eng. Proc. 2025, 84(1), 1; https://doi.org/10.3390/engproc2025084001 - 21 Jan 2025
Viewed by 416
Abstract
The 8th Mechanical Engineering, Science and Technology (MEST) Conference was held at the Universiti Muhammadiyah Malaysia, Bangunan Wisma MAIPs, Blok S1, Kompleks Desa Siswa, Uniciti Alam, 02100 Padang Besar, Perlis, Malaysia on 11–12 December 2024 [...] Full article

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10 pages, 3063 KiB  
Proceeding Paper
Clustering Batik SMEs: Open Innovation for Environmental Sustainability
by Amelia Kurniawati, Fahmy Habib Hasanudin, Fandi Achmad, Raihan Abdurrahman and Rizki Fajar Ahmad Gurnita
Eng. Proc. 2025, 84(1), 2; https://doi.org/10.3390/engproc2025084002 - 22 Jan 2025
Viewed by 335
Abstract
Environmental sustainability is challenging for SMEs, mainly due to SMEs’ limited resources. To achieve environmental sustainability, SMEs must innovate their production process and waste management. SMEs can utilize open innovation to counter their limited resources problem. This study aims to explore the clustering [...] Read more.
Environmental sustainability is challenging for SMEs, mainly due to SMEs’ limited resources. To achieve environmental sustainability, SMEs must innovate their production process and waste management. SMEs can utilize open innovation to counter their limited resources problem. This study aims to explore the clustering of SMEs based on their environmental sustainability achievement and the utilization of open innovation to achieve it. The data used in this study are from 38 SMEs that produce Batik and are located in Rembang Regency, Indonesia. The clustering process is performed using the K-Means algorithm. The results show that the data are grouped into two clusters. The first cluster, with 26 entities, tends to have higher environmental sustainability achievement and open innovation involvement than the second cluster with 12 entities. Therefore, the second cluster needs more attention from external stakeholders to encourage and support them in achieving environmental sustainability, primarily related to using environmentally friendly materials in production. Full article
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7 pages, 899 KiB  
Proceeding Paper
The In-Situ Epoxidation of Rubber Seed Oil (Hevea brasiliensis) by Peroxyacids
by Eni Budiyati, Auliya Rahmah and Nur Ahmad Fauzi
Eng. Proc. 2025, 84(1), 3; https://doi.org/10.3390/engproc2025084003 - 22 Jan 2025
Viewed by 252
Abstract
This paper adds to the sustainable materials field by in-situ epoxidation of rubber seed oil (RSO), a highly underutilized resource that has been sporadically used, using an optimized combination of 30% hydrogen peroxide and acetic/formic acid sulfuric acid. Most of the previous studies [...] Read more.
This paper adds to the sustainable materials field by in-situ epoxidation of rubber seed oil (RSO), a highly underutilized resource that has been sporadically used, using an optimized combination of 30% hydrogen peroxide and acetic/formic acid sulfuric acid. Most of the previous studies deal with more common vegetable oils, where the main focus in most is given to the epoxidation of these oils and their derivatives. The RSO contained a high iodine value around 135.36 g–I2/100 g. The central to this work is the systematic study of the oxirane number as a function of reaction temperature and the double bond:RCOOH:H2O2 molar ratios. By testing the temperatures of 40, 50, 60, and 70 °C and three specific molar ratios (1:0.6:1.4, 1:1:2, and 1:1.5:3), this research not only found the optimal conditions for epoxidation but also gave valuable information on the reaction kinetics of rubber seed oil. The results showed that a temperature of 60 °C with a 1:1:2 molar ratio gave the highest oxirane number, especially with performic acid, which was 3.200 mmol/g. Then, overall, formic acid consistently outperforms acetic acid in terms of product yields, facilitating a more effective epoxidation process. Full article
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10 pages, 1225 KiB  
Proceeding Paper
Compromise Parameters of Temperature, Light, and Noise in Confined Spaces on Work Duration and Number of Errors
by Nachnul Ansori, Fito Rolis Agung Pratama, Fitri Agustina, Issa Dyah Utami, Ernaning Widiaswanti and Rullie Annisa
Eng. Proc. 2025, 84(1), 4; https://doi.org/10.3390/engproc2025084004 - 23 Jan 2025
Viewed by 172
Abstract
The physical work environment may affect worker productivity. This study simulated physical work environment parameters, such as temperature, light, and noise, in a confined space in relation to work duration and the number of errors. This study was conducted on a laboratory scale [...] Read more.
The physical work environment may affect worker productivity. This study simulated physical work environment parameters, such as temperature, light, and noise, in a confined space in relation to work duration and the number of errors. This study was conducted on a laboratory scale involving six operators of different genders. Results show a difference in work duration, while no difference existed in the number of errors. Female participants were better at assembly work than male participants were. On the other hand, based on the variance, light and noise affected the work duration of male operators, while temperature and noise influenced female operators. In contrast, tested parameters did not affect the number of errors. An interaction between temperature and light affected male operators. Finally, further tests showed that noise was the factor that had the most influence on participants’ responses. Full article
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10 pages, 905 KiB  
Proceeding Paper
R Analysis for Optimizing Enzymatic Saccharification of Watermelon (Citrullus lanatus) Rind
by Wan Zafira Ezza Wan Zakaria, Khairunisa Yusof and Noor Aziah Serri
Eng. Proc. 2025, 84(1), 5; https://doi.org/10.3390/engproc2025084005 - 23 Jan 2025
Viewed by 234
Abstract
Watermelon waste was chosen as the main material due to the abundance of discarded rinds and the widespread consumption of this fruit in Malaysia. The cellulose, hemicellulose, and pectin within watermelon rinds, classified as lignocellulosic materials, underwent hydrolysis. This involved using cellulase and [...] Read more.
Watermelon waste was chosen as the main material due to the abundance of discarded rinds and the widespread consumption of this fruit in Malaysia. The cellulose, hemicellulose, and pectin within watermelon rinds, classified as lignocellulosic materials, underwent hydrolysis. This involved using cellulase and auxiliary enzymes like hemicellulose and pectinase to convert polysaccharides into simple sugars, yielding valuable end products. Thus, R software optimized saccharification yield in watermelon rind enzymatic hydrolysis. Four parameters were studied: substrate loading (1–5 g), enzyme loading (5–85 U/mg), temperature (35–55 °C), and hydrolysis time (6–30 h). Preliminary screening showed each parameter significantly affected saccharification yield. A mathematical model predicting optimal enzymatic hydrolysis conditions was developed through Response Surface Methodology (RSM) using Box–Behnken Design (BBD). The presented mathematical model exhibited a strong correlation between actual and predicted values, with a predicted R2 value of 0.96%. Optimization led to conditions of 1.15 g substrate, 24.85 U/mg enzyme, 44.79 °C temperature, and 11.47 h hydrolysis time. Under these conditions, the actual saccharification yield of watermelon rind reached 70.72%. Full article
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12 pages, 4206 KiB  
Proceeding Paper
Achieving Manufacturing Excellence Using Lean DMAIC
by Rindi Kusumawardani, Ana and Moses Laksono Singgih
Eng. Proc. 2025, 84(1), 7; https://doi.org/10.3390/engproc2025084007 - 23 Jan 2025
Viewed by 256
Abstract
This paper explores the role of business process optimization in achieving manufacturing excellence in railway manufacturing through Lean principles and Quality Function Deployment (QFD). It identifies key inefficiencies, such as waiting times, overproduction, and document errors, using the DMAIC method, along with Root [...] Read more.
This paper explores the role of business process optimization in achieving manufacturing excellence in railway manufacturing through Lean principles and Quality Function Deployment (QFD). It identifies key inefficiencies, such as waiting times, overproduction, and document errors, using the DMAIC method, along with Root Cause Analysis (RCA) and Failure Mode and Effect Analysis (FMEA), to prioritize waste reduction. A significant 42.86% of activities were classified as non-value added, pointing to substantial opportunities for improvement. This study proposes key solutions, including the development of a shared database, streamlined procedures, and the alignment of targets with the Master Production Schedule to reduce waste and improve operational efficiency. These recommendations aim to foster manufacturing excellence by enhancing communication, process integration, and employee training. Full article
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11 pages, 2239 KiB  
Proceeding Paper
Village Road Geometric Design Using AutoCAD® CIVIL 3D: The Case of Majalengka, Indonesia
by Renaldi Agustian, Andri Irfan Rifai, Arief Rijaluddin and Joewono Prasetijo
Eng. Proc. 2025, 84(1), 8; https://doi.org/10.3390/engproc2025084008 - 24 Jan 2025
Viewed by 368
Abstract
The latest technology to support geometric road planning must be implemented properly. Village road design using digital applications is believed to be able to produce the best planning. This paper aims to analyze the geometric planning of village roads using the AutoCAD® [...] Read more.
The latest technology to support geometric road planning must be implemented properly. Village road design using digital applications is believed to be able to produce the best planning. This paper aims to analyze the geometric planning of village roads using the AutoCAD® Civil 3D application. The data and planning location is on Village Road in Majalengka Regency, Indonesia. The research method used is to digitize manual planning using the AutoCAD application. The planning standard uses a combination of AASHTO and Indonesia Standard. The study results show that using AutoCAD® Civil 3D for village road planning provides convenience, speed, and the best planning precision. Full article
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8 pages, 2197 KiB  
Proceeding Paper
HHO Gas Production Assessment for Different NaOH Concentrations and Electrode Plates Under Hydrostatic Pressure
by Ummi Kultsum, Cahyo Jawoto Anggoro, Dewi Mahyunani and Andi Ibrahim Soumi
Eng. Proc. 2025, 84(1), 9; https://doi.org/10.3390/engproc2025084009 - 27 Jan 2025
Viewed by 250
Abstract
Hydrogen generated through electrolysis is a feasible, sustainable energy source. HHO gas, a combination of hydrogen and oxygen generated via water electrolysis, is a clean and efficient energy source. The influence of NaOH electrolyte concentrations (2%, 4%, 6%, 8%, and 10%) and electrode [...] Read more.
Hydrogen generated through electrolysis is a feasible, sustainable energy source. HHO gas, a combination of hydrogen and oxygen generated via water electrolysis, is a clean and efficient energy source. The influence of NaOH electrolyte concentrations (2%, 4%, 6%, 8%, and 10%) and electrode plate numbers (2, 4, and 6) on HHO gas production and hydrostatic pressure will be examined in this study. Both NaOH concentration and electrode plate number increase HHO gas generation and hydrostatic pressure. A 10% NaOH concentration with six plates produced the most pressure and highest rate of hydrogen production. Full article
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9 pages, 1533 KiB  
Proceeding Paper
Design of a Strategy for the Sustainable Development of the Bakery Industry in Medan City
by Tania Alda, Ahmad Shalihin, Chindy Elsanna Revadi, Fadylla Ramadhani Putri Nasution, Raja Ahsan Andifa, Natalia Sri Fifani Br Tarigan, Mhd Irsan, Andreas Pandapotan, Jasmine Meilani Halim and Ranti Widya Ningsih
Eng. Proc. 2025, 84(1), 10; https://doi.org/10.3390/engproc2025084010 - 27 Jan 2025
Viewed by 289
Abstract
Medan City has excellent potential to develop small and medium industries. One of the industries that has potential is the bakery industry. Based on the data obtained, it is known that the small-scale bakery industry dominates by 86%. To create a competitive bakery [...] Read more.
Medan City has excellent potential to develop small and medium industries. One of the industries that has potential is the bakery industry. Based on the data obtained, it is known that the small-scale bakery industry dominates by 86%. To create a competitive bakery industry, the products must be varied, innovative, good quality, follow market needs, and follow the eco-friendly production process. Based on this, the right strategy is needed so that the bakery industry can develop and increase its competitiveness towards sustainability. This research aims to create a strategy design that the bakery industry can implement to improve competitiveness and productivity toward sustainability. Based on the IFE and EFE matrix results, the bakery industry in Medan City is in quadrant IV, namely in the growth and built position. The right strategy, namely a market penetration strategy, and also a strategy for product development, is required. Based on the results of the QSPM matrix, the strategy with the highest score was obtained, namely, improvement in production processes in the bakery industry through the efficient and eco-friendly production process. Full article
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7 pages, 2494 KiB  
Proceeding Paper
The Effect of Using Variations of Radiator Coolant on the Effectiveness of Engine Cooling and the Rate of Corrosion of Radiator Materials in 1300 cc Cars
by Rizki Dwi Ardika, Sudarno Sudarno, Kuntang Winangun, Chikal Singgih Pangesthu, Nur Rashid Mat Nuri and Marwan Effendy
Eng. Proc. 2025, 84(1), 11; https://doi.org/10.3390/engproc2025084011 - 27 Jan 2025
Viewed by 234
Abstract
Engine coolant plays an important role in maintaining optimal engine performance, where it has good effectiveness and can prevent corrosion in the engine cooling system (radiator). This study aims to determine the effect of the use of coolant variations (engine coolant) on the [...] Read more.
Engine coolant plays an important role in maintaining optimal engine performance, where it has good effectiveness and can prevent corrosion in the engine cooling system (radiator). This study aims to determine the effect of the use of coolant variations (engine coolant) on the effectiveness of engine cooling (radiator) and to determine the effects of the coolants on the corrosion rate. To achieve this, coolant variations were used in the forms of mineral water, radiator coolant (prestone), and power coolant (TOP 1), which were applied at engine speeds of 1000, 1500, and 2000 rpm. Temperature data collection at the coolant inlet and outlet was carried out every 10 min at different rpm. The corrosion rate test used the AA 3102 series aluminum radiator material, which was tested using the potentiodynamic polarization method. The results showed that the best coolant effectiveness value was found for the power coolant (TOP1). This is influenced by the ethylene glycol contained within it, which helps to accelerate the decrease in temperature in the engine. The lowest corrosion rate was found for the power coolant (TOP1), with a corrosion rate value of 0.0074480 mm/year. This is because the power coolant (TOP1) contains organic carboxylate rust inhibitors, which can inhibit corrosion. Full article
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12 pages, 3101 KiB  
Proceeding Paper
A Bibliometric Analysis of Risk Management and Sustainability in the Agri-Food Supply Chain: Future Directions
by Dhita Morita Ikasari, Mokh Suef and Iwan Vanany
Eng. Proc. 2025, 84(1), 13; https://doi.org/10.3390/engproc2025084013 - 27 Jan 2025
Viewed by 258
Abstract
Sustainability issues often trigger risks that require systematic management. Risks associated with various sustainability factors in the supply chain are becoming more pertinent in many food industries because of growing concerns about food safety and quality. This paper aims to identify the development [...] Read more.
Sustainability issues often trigger risks that require systematic management. Risks associated with various sustainability factors in the supply chain are becoming more pertinent in many food industries because of growing concerns about food safety and quality. This paper aims to identify the development of research topics related to risk management and sustainability in agri-food supply chains and to identify future research opportunities related to these topics through bibliometric analysis. We analyzed 320 articles from the Scopus database to determine publication trends, the most productive journals, the largest publishers, and the most cited articles. We visualized this bibliometric analysis using VosViewer version 1.6.20. The analysis reveals that “sustainability” is the most frequently studied keyword, clustering together with “risk management”, “agri-food supply chain”, “circular economy”, “supply chain resilience”, “artificial intelligence”, and “blockchain”, indicating a close relationship between these topics. “Food supply chain” and “agri-food supply chain” are also topics that have emerged in the last few years. However, there are still a few authors who publish on this topic. The combination of these keywords offers a potential avenue for future research. Full article
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12 pages, 1564 KiB  
Proceeding Paper
Effect of Polylactic Acid (PLA) as Reinforcement for Jackfruit Seed Starch-Based Degradable Plastic
by Rozanna Dewi, Novi Sylvia and Medyan Riza
Eng. Proc. 2025, 84(1), 14; https://doi.org/10.3390/engproc2025084014 - 27 Jan 2025
Viewed by 283
Abstract
Synthetic plastics harm the environment, so finding better materials is important. Researchers have studied PLA and starch to replace non-degradable petrochemicals. This research uses jackfruit seed starch and PLA to make degradable plastics. The tensile strength of degradable plastics was 3.35–9.08 MPa. Tests [...] Read more.
Synthetic plastics harm the environment, so finding better materials is important. Researchers have studied PLA and starch to replace non-degradable petrochemicals. This research uses jackfruit seed starch and PLA to make degradable plastics. The tensile strength of degradable plastics was 3.35–9.08 MPa. Tests showed that the plastics were hydrophilic, meaning they bind to water and break down easily. The combination of the jackfruit seed starch with PLA-reinforced plastic had better thermal stability. Starch made the material swell more, while PLA made it swell less. Jackfruit seed starch-based plastics reinforced with PLA degraded in 52–56 days, meeting the ASTM 6400 standard. Full article
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15 pages, 2613 KiB  
Proceeding Paper
Correlation Between Friction Time, Rotational Speed, and Mechanical Properties in Aluminum-Based Friction Welding Processes
by Bibit Sugito, Agus Dwi Anggono, Agung Setyo Darmawan and Agus Hariyanto
Eng. Proc. 2025, 84(1), 15; https://doi.org/10.3390/engproc2025084015 - 27 Jan 2025
Viewed by 280
Abstract
In friction welding, rotational speed is a critical parameter that influences the welding outcomes by interacting with time and temperature variables. This study investigates the effects of varying friction times on the microstructure, hardness, and mechanical properties of friction-welded aluminum alloys. The experiments [...] Read more.
In friction welding, rotational speed is a critical parameter that influences the welding outcomes by interacting with time and temperature variables. This study investigates the effects of varying friction times on the microstructure, hardness, and mechanical properties of friction-welded aluminum alloys. The experiments involved analyzing samples using Scanning Electron Microscopy with Energy Dispersive Spectroscopy (SEM-EDS) to assess elemental composition, alongside measuring hardness, stress, and strain values. Microstructural analysis revealed that a rotation duration of 7 s produced finer grain boundaries than those observed at 3 and 5 s, correlating with enhanced mechanical properties. At a rotational speed of 1450 rpm with a friction time of 3 s, the maximum stress and strain values reached 192.85 MPa and 19.48%, respectively. Increasing the friction time to 5 s resulted in a maximum stress of 196.60 MPa and a strain value of 17.50%, while at 7 s, the maximum stress reached 194.64 MPa with a strain of 17.66%. Findings indicate that prolonged friction time tends to increase material brittleness. Hardness testing at 1450 rpm revealed values of 73.59 VHN at 3 s, 70.23 VHN at 5 s, and 79.47 VHN at 7 s, with increased rotation time resulting in finer grain structure and improved hardness. SEM-EDS analysis across all conditions (3, 5, and 7 s) consistently identified aluminum (Al) as the primary elemental constituent, reflective of the base alloy composition. These results highlight the influence of friction time and rotational speed on the material’s microstructural integrity and mechanical performance in friction welding applications. Full article
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15 pages, 2406 KiB  
Proceeding Paper
Supporting Sustainable Workforce Management for Worker Illness Absence Through Predictive Analytics
by Ida Lumintu and Achmad Maududie
Eng. Proc. 2025, 84(1), 17; https://doi.org/10.3390/engproc2025084017 - 28 Jan 2025
Viewed by 196
Abstract
This study aimed to predict employee sickness absence, vital for sustainable workforce management and organizational productivity. Despite its importance, gaps exist in using advanced machine learning for this purpose. This research developed and validated models—Gradient Boosting, CatBoost, and Random Forest—focused on predictors like [...] Read more.
This study aimed to predict employee sickness absence, vital for sustainable workforce management and organizational productivity. Despite its importance, gaps exist in using advanced machine learning for this purpose. This research developed and validated models—Gradient Boosting, CatBoost, and Random Forest—focused on predictors like health conditions, mental well-being, and work stress. Using a factory worker dataset, this study conducted feature engineering, causal inference, and model performance evaluation. Random Forest proved especially effective in predicting absence, with key factors including recent performance and health. The findings support targeted interventions and efficient resource allocation, promoting sustainable business practices. Full article
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11 pages, 4780 KiB  
Proceeding Paper
Development and Performance Analysis of Coconut Coir Waste-Based Recycle Papers for Cooling Pad Applications
by Agus Dwi Anggono, Agung Setyo Darmawan and Agus Yulianto
Eng. Proc. 2025, 84(1), 18; https://doi.org/10.3390/engproc2025084018 - 28 Jan 2025
Viewed by 313
Abstract
Paper is an essential material in daily life, yet its widespread use contributes significantly to waste, which poses environmental hazards. In Indonesia, paper waste is one of the most substantial types of solid waste. Recycling waste paper into new, usable products offers both [...] Read more.
Paper is an essential material in daily life, yet its widespread use contributes significantly to waste, which poses environmental hazards. In Indonesia, paper waste is one of the most substantial types of solid waste. Recycling waste paper into new, usable products offers both environmental and economic benefits. This study investigates the tensile strength, tearing strength, and microstructure of recycled paper produced using 70 g HVS waste paper, coconut husk fibers, NaOH as a chemical treatment, and tapioca powder as an adhesive. NaOH concentrations were varied at 2%, 4%, 6%, and 8% to assess their effects on the mechanical properties of the recycled paper. Results from tensile strength tests indicated that the highest tensile strength, 2.2774 MPa, was achieved with a 6% NaOH concentration, while the lowest tensile strength, 1.1065 MPa, was observed at a 4% NaOH concentration. Tearing strength tests showed that the highest tearing strength of 2.6145 MPa was obtained with a 4% NaOH concentration, whereas the lowest tearing strength of 1.8481 MPa was observed at an 8% NaOH concentration. Microstructural analysis of the fracture and tear zones revealed non-uniform fiber pullout, highlighting the influence of NaOH concentration on fiber bonding. These findings provide insights into optimizing NaOH concentration for improved mechanical properties in recycled paper products. Full article
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12 pages, 2659 KiB  
Proceeding Paper
Risk Mitigation Analysis for Tofu Production Process to Minimize Product Defects Using House of Risk Approach
by Hadi Susanto, Sheila Amalia Salma and Hanifa Rahmani
Eng. Proc. 2025, 84(1), 19; https://doi.org/10.3390/engproc2025084019 - 28 Jan 2025
Viewed by 192
Abstract
Enhancing the sustainability of manufacturing systems requires reducing product defects through effective management of risks that impact product quality. A crucial component in minimizing defects is the adoption of robust risk management strategy. This study examines risk mitigation in the tofu production process [...] Read more.
Enhancing the sustainability of manufacturing systems requires reducing product defects through effective management of risks that impact product quality. A crucial component in minimizing defects is the adoption of robust risk management strategy. This study examines risk mitigation in the tofu production process to reduce product defects, by employing the House of Risk (HOR) framework to prioritize mitigation efforts. Data were collected through observations, in depth interviews, and focus group discussions, following the two-step HOR methodology. The analysis identified 12 risk events and seven risk agents, along with six prioritized mitigation strategies, based on the Aggregate Risk Potential (ARP) ranking of the identified risk agents. The highest-priority strategy involves developing standardized work instructions for the tofu production process. This study offers practical insights for companies seeking to lower defect rates, thereby supporting the sustainability of their manufacturing systems. Full article
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9 pages, 2544 KiB  
Proceeding Paper
Microstructural and Mechanical Analysis of Aluminum Joints Under Varying Rotational Speeds in Friction Welding with Post-Quenching
by Bibit Sugito, Agus Dwi Anggono, Agung Setyo Darmawan and Agus Hariyanto
Eng. Proc. 2025, 84(1), 20; https://doi.org/10.3390/engproc2025084020 - 29 Jan 2025
Viewed by 279
Abstract
This study examines the effects of rotational speed and post-weld quenching on aluminum friction-welded joints’ microstructure, hardness, and mechanical properties. Tests were conducted at rotational speeds of 1250 rpm, 1350 rpm, and 1450 rpm, with elemental composition assessed via SEM–EDS, and the hardness [...] Read more.
This study examines the effects of rotational speed and post-weld quenching on aluminum friction-welded joints’ microstructure, hardness, and mechanical properties. Tests were conducted at rotational speeds of 1250 rpm, 1350 rpm, and 1450 rpm, with elemental composition assessed via SEM–EDS, and the hardness and mechanical properties were measured. The results showed that aluminum (Al) was the primary element in all samples. Hardness increased with rotational speed, reaching 70 VHN at 1250 rpm, 80 VHN at 1350 rpm, and 81 VHN at 1450 rpm. The highest stress was recorded at 1350 rpm, with the lowest at 1450 rpm. The aluminum joints exhibited high stress and strain values, confirming their ductile nature. These findings highlight the significant influence of rotational speed and quenching on friction-welded aluminum’s microstructural and mechanical behavior, providing insights for optimizing welding parameters for improved material performance in industrial applications. Full article
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9 pages, 823 KiB  
Proceeding Paper
Dual Collection Channels Under a Carbon Tax Scheme in CLSC: Decentralized vs. Alliance
by Nur Layli Rachmawati and Chung-Chi Hsieh
Eng. Proc. 2025, 84(1), 21; https://doi.org/10.3390/engproc2025084021 - 27 Jan 2025
Viewed by 80
Abstract
This paper compares dual collection mode strategies under carbon tax regulation: (1) a decentralized strategy when both manufacturer and retailer collect EoL independently and they determine their pricing and collection decision separately and (2) an alliance strategy by incorporating backward integration, when manufacturer [...] Read more.
This paper compares dual collection mode strategies under carbon tax regulation: (1) a decentralized strategy when both manufacturer and retailer collect EoL independently and they determine their pricing and collection decision separately and (2) an alliance strategy by incorporating backward integration, when manufacturer and retailer make an alliance to recycle EoL but their pricing decisions are determined independently. The results show that the alliance strategy performs better in terms of total supply chain profit. Performing alliances benefits the manufacturer and supply chain. Full article
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8 pages, 6349 KiB  
Proceeding Paper
Enhancing Hydrophilicity and Efficiency of PVC-Based Nanofiber Membranes by Adding PEG, Chitosan, and Silver Nanoparticles for Water Filtration
by Harini Sosiati, Lambang Prabowo Iqbal Hanafi, Kasyi Ridha Takiyudin, Sabtanti Harimurti and Yusmaniar Yusmaniar
Eng. Proc. 2025, 84(1), 22; https://doi.org/10.3390/engproc2025084022 - 29 Jan 2025
Viewed by 156
Abstract
This study aims to investigate PVC-based nanofiber membranes added with PEG, chitosan, and silver nanoparticles (CSNPs and AgNPs) to improve their hydrophilicity and filtration efficiency. The nanofiber membranes were fabricated by an electrospinning technique. All nanofiber membranes were subjected to a tensile test [...] Read more.
This study aims to investigate PVC-based nanofiber membranes added with PEG, chitosan, and silver nanoparticles (CSNPs and AgNPs) to improve their hydrophilicity and filtration efficiency. The nanofiber membranes were fabricated by an electrospinning technique. All nanofiber membranes were subjected to a tensile test according to the ASTM D882 standard and water contact angle (WCA) measurement. SEM was used to examine nanofiber morphology. Adding PEG to PVC increased hydrophilicity, lowering the water contact angle from 135° to 83°, while adding CSNPs and AgNPs to PEG/PVC slightly decreased it. The inclusion of these nanoparticles improved membrane tensile strength. In filtration tests, 0.5% AgNPs/PEG/PVC worked better against Colitinja bacteria than the CSNP variant. However, both types of nanoparticles were equally effective at inhibiting E. coli. These results indicate that 0.5% CSNP/PEG/PVC and 0.5% AgNPs/PEG/PVC membranes are promising for antibacterial water filtration applications due to their hydrophilic and durable properties. Full article
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241 KiB  
Proceeding Paper
Implementation of Green Infrastructure in Sustainable Transportation in Supporting Urban Mobility: A Literature Review
by Aditya Restu Hapriyanto and Hafidzul Azmi
Eng. Proc. 2025, 84(1), 25; https://doi.org/10.3390/engproc2025084025 - 30 Jan 2025
Viewed by 13
Abstract
This research explores the implementation of green infrastructure in supporting sustainable transportation systems to improve urban mobility in big cities. The background of this research is based on the need to reduce the environmental impact of the transportation sector, which contributes significantly to [...] Read more.
This research explores the implementation of green infrastructure in supporting sustainable transportation systems to improve urban mobility in big cities. The background of this research is based on the need to reduce the environmental impact of the transportation sector, which contributes significantly to carbon emissions and air pollution, especially in dense urban areas. Green infrastructure, such as bicycle lanes, pedestrian-friendly sidewalks, and green open spaces, has been proven to have a positive impact in reducing pollution and improving people’s quality of life. This research aims to analyze how the implementation of green infrastructure can support sustainable transportation and improve the quality of mobility in urban areas, with a focus on case studies of cities such as Copenhagen, Amsterdam, and Singapore, and large cities in Indonesia, including Bandung. Using the literature review method, this research analyzes various reports, journal articles, and statistical data from previous studies regarding the impact of green infrastructure in reducing emissions and promoting environmentally friendly transportation. The results of the discussion show that the implementation of green infrastructure provides various benefits, such as reducing carbon emissions, improving public health, and creating a more comfortable urban environment. Large cities in Europe and Asia have been pioneers in implementing this system, while in Indonesia, cities such as Jakarta, Surabaya, and Bandung have begun to adopt similar concepts with some success, although they still face various challenges. In conclusion, green infrastructure is an important element in sustainable city development that not only improves mobility but also the overall quality of life of society. Full article
11 pages, 3826 KiB  
Proceeding Paper
Analysis of a 40-Story Office Building Combining a Post Tensioned Flat Slab with Separated Gravity Lateral Resisting Implementation
by Alexandra Patricia Andriani, Jessica Sjah, Indra Nurudin Fathoni and Nuraziz Handika
Eng. Proc. 2025, 84(1), 26; https://doi.org/10.3390/engproc2025084026 - 30 Jan 2025
Viewed by 102
Abstract
Compared to other countries, the adoption of post-tensioned flat slab (PTFS) in Indonesia is relatively limited due to the susceptibility of flat slab to lateral forces. Nevertheless, flat slabs in high seismic zones scan still be achieved by utilizing the separated gravity lateral [...] Read more.
Compared to other countries, the adoption of post-tensioned flat slab (PTFS) in Indonesia is relatively limited due to the susceptibility of flat slab to lateral forces. Nevertheless, flat slabs in high seismic zones scan still be achieved by utilizing the separated gravity lateral resisting (SGLR) system. This study analyzes a 40-story office building by comparing the structural response, volume, and cost of PTFS with conventional structures. The findings reveal that PTFSs exhibit greater story drift and displacement but experience reduced story shear and overturning moments with a reduction in concrete volume of up to 10% and a 6% decrease in overall costs. Full article
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10 pages, 1035 KiB  
Proceeding Paper
Conceptual Framework for Halal Supply Chain Traceability and Food Safety in Indonesia Based on Blockchain Technology and Internet of Things to Support Sustainable Development
by Miftakhurrizal Kurniawan, Suparno Suparno and Iwan Vanany
Eng. Proc. 2025, 84(1), 27; https://doi.org/10.3390/engproc2025084027 - 31 Jan 2025
Viewed by 86
Abstract
Halal supply chain traceability and food safety are critical issues in the food industry, especially in Indonesia, which has the largest Muslim population in the world. This study aims to develop a halal supply chain traceability and food safety model based on Blockchain [...] Read more.
Halal supply chain traceability and food safety are critical issues in the food industry, especially in Indonesia, which has the largest Muslim population in the world. This study aims to develop a halal supply chain traceability and food safety model based on Blockchain and Internet of Things (IoT) that can improve transparency, efficiency, consumer trust in food products, and support sustainable development. This study proposes a conceptual framework for a halal supply chain traceability and food safety model based on Blockchain and IoT technologies. This model is expected to help Indonesia address issues related to halal assurance and food safety. Full article
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16 pages, 2326 KiB  
Proceeding Paper
Quality Control Analysis in the Production of Decorative Resin Lamps Using the Six Sigma and Failure Mode and Effect Analysis Methods
by Arinda Soraya Putri, Adhimsa Arrizal Salam, Ahmad Kholid Al Ghofari and Siti Nandiroh
Eng. Proc. 2025, 84(1), 30; https://doi.org/10.3390/engproc2025084030 - 3 Feb 2025
Abstract
A creative industry company producing resin-based decorative lamps is facing quality issues due to production defects. This study applied the Six Sigma and FMEA methods to identify controls, analyze causes, and propose improvements. Six Sigma reduces defects using the DMAIC approach, while FMEA [...] Read more.
A creative industry company producing resin-based decorative lamps is facing quality issues due to production defects. This study applied the Six Sigma and FMEA methods to identify controls, analyze causes, and propose improvements. Six Sigma reduces defects using the DMAIC approach, while FMEA assesses risks through the Risk Priority Number (RPN). The analysis showed a DPMO of 14,587.89 and a sigma level of 3.7, aligning with industry standards in Indonesia. Key defects included bubbles (57%), uneven surfaces (24%), and cracks (19%). Suggested improvements included training, production evaluations, rotary casting tools, safety measures, and enhanced cleanliness in the sanding area. Full article
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7 pages, 2884 KiB  
Proceeding Paper
Experimental Study of Amorphous Photovoltaic Systems in Indoor Performance with Different Coolants
by Dessy Ade Pratiwi, Andi Ibrahim Soumi, Gumilang Wicaksono, Nurmuntaha Agung Nugraha, Azizah Fatmawati, Rizki Nurilyas Ahmad, Wafiq Kurniawan and Cahyo Jawoto Anggoro
Eng. Proc. 2025, 84(1), 84024; https://doi.org/10.3390/engproc2025084024 - 29 Jan 2025
Viewed by 158
Abstract
The aim of this research is to investigate the performance of indoor amorphous photovoltaic systems with PVC water cooling and compare them with those using heatsink cooling. The amorphous approach used in this study involves water flowing through a PVC pipe and a [...] Read more.
The aim of this research is to investigate the performance of indoor amorphous photovoltaic systems with PVC water cooling and compare them with those using heatsink cooling. The amorphous approach used in this study involves water flowing through a PVC pipe and a heatsink cooler. The circular heatsink that was used has fins all around it. The water flow through the pipe is pumped from the reservoir to the PVC pipe. The study found that a PVC water flow-based active cooling system is the most effective at preserving thermal stability and improving the performance of amorphous PV modules under high light intensity circumstances, providing insights for future advancements. Full article
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