cover
Contact Name
Yuliah Qotimah
Contact Email
yuliah@itb.ac.id
Phone
+6281221296669
Journal Mail Official
jets@itb.ac.id
Editorial Address
ITB Journal, Gedung CRCS ITB Lantai 6 Jalan Ganesa No. 10 40132 Bandung - Indonesia
Location
Kota bandung,
Jawa barat
INDONESIA
Journal of Engineering and Technological Sciences
ISSN : 23385502     EISSN : 23375779     DOI : 10.5614/j.eng.technol.sci
Core Subject : Engineering,
ournal of Engineering and Technological Sciences welcomes full research articles in: General Engineering Earth-Surface Processes Materials Science Environmental Science Mechanical Engineering Chemical Engineering Civil and Structural Engineering Authors are invited to submit articles that have not been published previously and are not under consideration elsewhere.
Articles 132 Documents
Classifying Rockburst Events and Intensity in Underground Mines using Grey Wolf Optimization–Support Vector Machine and Extreme Gradient Boosting Nugraha, Adhitya Dwi; Wattimena, Ridho Kresna; Handari, Bevina Desjwiandra; Hertono, Gatot
Journal of Engineering and Technological Sciences Vol. 57 No. 6 (2025): Vol. 57 No. 6 (2025): December
Publisher : Directorate for Research and Community Services, Institut Teknologi Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.5614/j.eng.technol.sci.2025.57.6.6

Abstract

Rockbursts are destructive accidents that often occur in underground mines. With the advancement of technology, machine learning has emerged as an alternative solution that can be used for rockburst mitigation. In this research, we classify rockburst events and their intensities in underground mines using two machine learning models: grey wolf optimization–support vector machine (GWO–SVM) and extreme gradient boosting (XGBoost). Rockburst events are classified into two categories: Existent and None. Meanwhile, the intensities are classified into three categories: weak, moderate, and strong. The implementation used 476 cases of rockbursts with six variables: maximum tangential stress, uniaxial compressive strength, uniaxial tensile strength, stress coefficient, rock brittleness coefficient, and elastic strain index. Both models can better predict the “Existent” rockburst class with a “Weak” intensity compared with the other intensity classes. The performances of the models are evaluated using different proportions of training data, ranging from 50% to 90%. Both models have the same performance for rockburst event classification with 97.53% accuracy, 0.9444 precision, 0.9846 recall, and 0.9628 F1-score. Meanwhile, for intensity classification, XGBoost outperforms GWO-SVM with its 88.24% accuracy, 0.8413 precision, 0.9137 recall, and 0.8651 F1-score.
The Initial Development of Integrated Add-On Tele-Ultrasonography for Monitoring the Health of Pregnant Women and Fetuses in the Community Health Centers in Indonesia: - Susanti, Hesty; Setiyadi, Suto; Puspitasari, Dita; Alia, Fenty; Ramadhan, Muhammad Rizqi Syah
Journal of Engineering and Technological Sciences Vol. 57 No. 6 (2025): Vol. 57 No. 6 (2025): December
Publisher : Directorate for Research and Community Services, Institut Teknologi Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.5614/j.eng.technol.sci.2025.57.6.9

Abstract

Maternal health and fetal growth in rural areas require special attention due to limited access to adequate healthcare systems. Early detection of fetal health conditions can be achieved using B-mode ultrasonography (USG). However, expectant mothers in these regions often lack regular to regular check-up, even when healthcare facilities are available there may not be trained professionals available to analyze the B-mode images obtained in the Community Health Centres. To address this gap, a tele-USG system was developed that allows healthcare workers in remote areas to operate basic USG equipment and transmit real-time images to specialist doctors at higher-level healthcare facilities. During system development, a general-purpose USG phantom was used to test parameters: penetration depth, geometric accuracy, focal zone, and axial and lateral resolution. Testing confirmed that both USG and laptop used for streaming produce reliable and accurate results. A slight geometric representation differences of 2.74% (approximately 1 cm per target) was observed, attributed to dimensional distortion between devices with different monitor sizes. In geometric accuracy tests, five out of eight vertical and six out of seven horizontal targets were successfully detected. The smallest variation of 0.028 mm occurred at 5 MHz frequency, demonstrated high precision focal zone measurements. The axial resolution ranged between 0.25-0.5 mm, while lateral resolution ranged from 1.0-2.0 mm, indicating strong capability for fine-detail imaging. Overall, the system exhibited high sensitivity and excellent imaging performance, offering a promising solution to enhance maternal and fetal healthcare challenges faced by rural communities in Indonesia through accessible real-time diagnostic support
Sustainable thermal insulation of geopolymer blocks using solid waste: palm oil ash and palm oil clinker Hawa, Abideng; Salaemae, Preecha
Journal of Engineering and Technological Sciences Vol. 57 No. 6 (2025): Vol. 57 No. 6 (2025): December
Publisher : Directorate for Research and Community Services, Institut Teknologi Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.5614/j.eng.technol.sci.2025.57.6.8

Abstract

This paper has analyzed the thermal insulation of geopolymer blocks prepared using palm oil ash (POA) with the addition of alumina powder (AP) and field Para rubber latex (FPRL). The block samples were set up to use 3 and 5 channels and channel width of 2 and 4 mm each with geopolymer binder as POA (containing 5% FPRL and 0%, 2.5%, 5%, 7.5%, and 10% AP) and POC as fine aggregate. The compressive strength, water absorption, bulk density of the geopolymer mortars and thermal conductivity of geopolymer blocks were explored. The AP and FPRL had minimal impact on the compressive strength of the geopolymer mortars and the greater the amount of AP the less water was absorbed. Thermal conductivity of 4 mm wide channel geopolymer blocks was lower than that of 2 mm wide channel blocks and 5 channels blocks had lower thermal conductivity in comparison to 3 channel blocks. The geopolymer blocks had low thermal conductivity relative to the commercial concrete blocks. This study offers valuable information to the application of geopolymers made of POA with FPRL and AP to produce geopolymer materials, POC as a fine aggregate to produce green building materials with enhanced thermal insulation.
Electrochemiluminescence sensor based on GDYO-QD@M-ZnO and its application in the detection of free radicals and antioxidants Tian, Gang; Yang, Cong; Tian, Yihang; Wang, Zihuan; Dang, Yannan
Journal of Engineering and Technological Sciences Vol. 57 No. 6 (2025): Vol. 57 No. 6 (2025): December
Publisher : Directorate for Research and Community Services, Institut Teknologi Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.5614/j.eng.technol.sci.2025.57.6.7

Abstract

In view of the problems such as low luminous efficiency, poor stability and weak anti-interference ability of traditional electrochemiluminescence sensors, this study prepared graphdiyne oxide quantum dots by acid oxidation method and synthesized metal-organic skeleton derived zinc oxide by high-temperature calcination. The two were combined to construct a new ECL sensor. It is used for detecting free radicals and antioxidants such as vitamin C, trixerutin, and metformin hydrochloride. The results showed that GDYO-QD was successfully combined with M-ZnO. The constructed sensor has excellent electronic transmission ability, and the electrochemiluminescence signal is significantly enhanced compared with a single material, and has good detection performance for the target analyte. This study provides new ideas and practical tools for developing high-performance electrochemiluminescence sensors and effectively detecting free radicals and antioxidants.
Multi-criteria Decision Making to Improve Displacement Amplification Ratio of an Amplifying Compliant Mechanism Flexure Hinge Huynh, Ngoc Thai; Huynh, Van Nam; Tran, Quoc Nhiem; Phan, Chi Bao; Vu, Minh Hung; Nguyen, Trieu Khoa; Nguyen, Quoc Manh
Journal of Engineering and Technological Sciences Vol. 57 No. 6 (2025): Vol. 57 No. 6 (2025): December
Publisher : Directorate for Research and Community Services, Institut Teknologi Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.5614/j.eng.technol.sci.2025.57.6.5

Abstract

Multi-criteria decision-making methods including the Extended Additive Ratio Assessment (EAMR), Simple Additive Weighting (SAW), Weighted Aggregated Sum Product Assessment (WASPAS), and Evaluation based on Distance from Average Solution (EDAS) were employed in conjunction with the Taguchi method and finite element method (FEM) to optimize the displacement amplification of an amplifying compliant mechanism utilizing flexure joints. Initially, design variables for the compliant mechanism amplifier were selected. Minitab software was utilized to generate 27 experimental scenarios, and SolidWorks was employed to design 27 models of compliant mechanisms amplifier with flexure hinges. The stress and displacement of each design were estimated by FEM in ANSYS. The optimal mechanism was identified based on the largest displacement criterion as well as ensuring the smallest stress, as determined through the multi-criteria decision-making techniques and validated using the Taguchi method, variance analysis, and 3D surface plots. The predicted outcomes from the optimization methods are compared with FEM results for verification. For the EAMR method, the predicted and optimal values are 0.742046 and 0.74968, respectively. The SAW method yields values of 0.88684 (predicted) and 0.89210 (optimal), while the WASPAS method produces 0.8432 and 0.8481. The EDAS method results are 0.7978 (predicted) and 0.8187 (optimal). For displacement (Di), the predicted and optimal values are 0.65269 and 0.65238, respectively, and for stress (St), they are 49.3398 and 48.7950. In all methods, the deviation between predicted and optimal values remains under 3%. The resulting displacement amplification ratio (DAR) of the final mechanism is 65,237.
Sensitive Detection of Rhodamine B Using Surface Enhanced Raman Spectroscopy with a BiFeO3 based Substrate Mayora, Diva Cassia; Triyono, Djoko; Shiddiq, Muhandis; Rafsanjani, Rifqi Almusawi; Alaih, Akhmad Futukhillah Fataba
Journal of Engineering and Technological Sciences Vol. 57 No. 6 (2025): Vol. 57 No. 6 (2025): December
Publisher : Directorate for Research and Community Services, Institut Teknologi Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.5614/j.eng.technol.sci.2025.57.6.10

Abstract

Surface-Enhanced Raman Spectroscopy (SERS) is a highly effective technique for detecting trace amounts of molecular species. However, the widespread use of conventional noble metal substrates is limited by high fabrication costs and scalability issues. Perovskite materials have recently emerged as promising alternatives, though many are lead-based and pose environmental risks. In this study, we present a lead-free bismuth ferrite (BiFeO₃) perovskite synthesized via the sol–gel method as a novel SERS substrate for the detection of Rhodamine B, a toxic dye commonly used illicitly in food products. Comprehensive characterization using X-ray Diffraction (XRD), X-ray Fluorescence (XRF), and UV-Visible Diffuse Reflectance Spectroscopy confirmed the successful formation of a single-phase rhombohedral structure with a direct bandgap of 2.1 eV, indicating strong visible-light absorption. The BiFeO₃ substrate demonstrated effective SERS performance, facilitating a detection of Rhodamine B at concentrations as low as 10 ppm. These results highlight the potential of lead-free BiFeO₃ perovskites as practical and environmentally friendly alternatives to noble metals for SERS-based detection of hazardous dyes and other environmental contaminants.
Analysis of Gravity Data for Basement Depth Estimation of the Western Part of Java Island, Indonesia Ananda, Riski; Azhari, Na'ila Yuni; Rahadinata, Tony; Grandis, Hendra
Journal of Engineering and Technological Sciences Vol. 58 No. 1 (2026): February 2026 (In Progress)
Publisher : Directorate for Research and Community Services, Institut Teknologi Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.5614/j.eng.technol.sci.2026.58.1.1

Abstract

Studying the basement depth and fault structures is crucial for understanding basin geometry and fluid migration pathways. This study aims to understand basin geometry using gravity data in the Banten area, Indonesia, as a region with possible hydrocarbon prospects. Anomaly gradients derived from the Bouguer anomaly were conducted for fault analysis. Meanwhile, basement depth estimation was performed using Euler deconvolution, with a Structural Index (SI) of 0 and window sizes of 7 km × 7 km and 10 km × 10 km. Additionally, 3D inversion modelling with Grablox 1.6 was applied to model the sediment-basement interface. The anomaly gradient results correlate well with regional fault structures, and local structures align with high-gradient areas in southern Banten. Furthermore, high-gradient values are associated with hydrocarbon seep locations, indicating fractures or faults transporting hydrocarbons. The depth estimations of Euler deconvolution cannot accurately identify the discontinuities forming the basin. However, they align reasonably well with the sediment-basement interface of the density model. The model reveals basin structures up to 7.8 km deep in the Bogor Basin and its surroundings, consistent with low residual anomaly areas, aiding in the early estimation of lateral basin boundaries.
Dynamic Modeling and Response Characteristics Analysis in High-Temperature Melting and Rolling Process of Laminated Steel Xin, Yanli; Gao, Zhiying; Wang, Xiaoyong; Zhang, Qingdong; Zhou, Xiaomin
Journal of Engineering and Technological Sciences Vol. 58 No. 1 (2026): February 2026 (In Progress)
Publisher : Directorate for Research and Community Services, Institut Teknologi Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.5614/j.eng.technol.sci.2026.58.1.2

Abstract

High-temperature melting and rolling is the key process of laminated steel production. The dynamic fluctuation of the rolling force during the film covering process causes an alternating effect of positive and negative pressures in the film covering area. The roll vibration causes the film to vibrate up and down, leading to the generation and intensification of bubbles, which seriously affects the product quality. In this study, considering the nonlinear stiffness characteristics of a polyethylene terephthalate (PET) film under unidirectional compression in the roll gap, a melting and rolling dynamic model with the structure and process coupled was established. Taking the melting layer and the rolling force as intermediate variables, process parameters such as strip temperature and rolling speed were introduced into the dynamic model, and the influence of process parameters on the film filling rate and the roll vibration displacement response was discussed. Considering the external disturbances of the strip thickness difference and the roll eccentricity, the dynamic characteristics of the rolling force, roll displacement, and filling rate under different strip temperatures and rolling speeds were analysed. The research results indicated that with an increase in the rolling speed and a decrease in the strip temperature, the filling rate, roll displacement, and rolling force increased, affecting the quality of laminated steel. Therefore, modeling the dynamic mechanism and studying the dynamic rolling force characteristics of the high-temperature melting and rolling process of laminated steel can provide a theoretical basis for controlling and optimizing of the film covering process.
Emissions Analysis of Railway Transportation in Java Island Indonesia for Climate Change Mitigation – Study Case in 2023 Nurjani, Emilya; Astuti, Bernadetta Indri Dwi; Firmansyah, Anugrah Jorgi; Fawzia, Annisa Ayu; Sekaranom, Andung Bayu; Suarma, Utia
Journal of Engineering and Technological Sciences Vol. 58 No. 1 (2026): February 2026 (In Progress)
Publisher : Directorate for Research and Community Services, Institut Teknologi Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.5614/j.eng.technol.sci.2026.58.1.3

Abstract

Rail transportations are among the most environmentally friendly modes of transportation due to their low per capita emissions and carbon footprint. This study aims to analyze the total CO2 emissions and per capita emissions of long-distance and local rail transports operating on the island of Java in 2023. Emission calculations were conducted using the IPCC methodology and Sebos’s approach, incorporating factors such as locomotive types, which predominantly use B30 biodiesel and electricity as energy sources. The results are presented in the form of spatial maps for a comprehensive visualization. Key findings indicate that high emissions and per capita emissions are not exclusively associated with rail transports operating in urban areas. Areas with high long-distance train emissions (> 30,000 tons of CO2) are OP VI Yogyakarta and OP VIII Surabaya. High per capita emissions (> 0.005 tons of CO2/capita/year) are OP I Jakarta and OP VII Madiun. Instead, factors such as travel frequency, route length, locomotive type, fuel type, and passenger volume significantly influence emission outcomes. Commuter trains contribute higher emissions than long-distance trains and local non-commuter trains. The highest total emissions were recorded for the Jabodetabek Commuter Line, amounting to 14,545,676 tons of CO2. This line also exhibited the highest per capita emissions due to its high operational frequency and daily service schedule. These findings highlight the need for strategies to optimize rail transports operations and minimize environmental impacts, particularly in high-frequency commuter services.
Effect of Bolting on the Face of a Crushed Soft Rock Tunnel Chen, Lei; Cao, Yuxuan; Wen, Tongkai; Zhang, Haobin; Song, Zhanping
Journal of Engineering and Technological Sciences Vol. 58 No. 1 (2026): February 2026 (In Progress)
Publisher : Directorate for Research and Community Services, Institut Teknologi Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.5614/j.eng.technol.sci.2026.58.1.4

Abstract

To study the large deformation of surrounding rock during the passage of a soft rock tunnel through a fractured zone, a numerical simulation analysis was conducted on a specific tunnel section. The investigation focused on the extrusion deformation at the face, settlement deformation of the arch roof, and stress in the surrounding rock, considering the two support types used in the New Austrian Tunneling Method. The results show that the use of anchor bolts can reduce the pre-convergence deformation by 58.1% and its proportion by 23.5%, significantly increasing the minimum principal stress at the palm surface, maintaining the advanced core soil in the three-way stress state, and enhancing the longitudinal arch effect. These factors enhance the overall stability of the tunnel. Field monitoring data reveal that the convergence deformation of each part of the tunnel remains within a reasonable range, demonstrating the effectiveness of the face bolt in controlling deformation and adjusting the surrounding rock stress in the stratum, characterized by low quality and high degree of crushing.