cover
Contact Name
Andi Adriansyah
Contact Email
andi@mercubuana.ac.id
Phone
+628111884220
Journal Mail Official
sinergi@mercubuana.ac.id
Editorial Address
Fakultas Teknik Universitas Mercu Buana Jl. Raya Meruya Selatan, Kembangan, Jakarta 11650 Tlp./Fax: +62215871335
Location
Kota adm. jakarta barat,
Dki jakarta
INDONESIA
Sinergi
ISSN : 14102331     EISSN : 24601217     DOI : https://dx.doi.org/10.22441/sinergi
Core Subject : Engineering,
SINERGI is a peer-reviewed international journal published three times a year in February, June, and October. The journal is published by Faculty of Engineering, Universitas Mercu Buana. Each publication contains articles comprising high quality theoretical and empirical original research papers, review papers, and literature reviews that are closely related to the fields of Engineering (Mechanical, Electrical, Industrial, Civil, and Architecture). The theme of the paper is focused on new industrial applications and energy development that synergize with global, green and sustainable technologies. The journal registered in the CrossRef system with Digital Object Identifier (DOI). The journal has been indexed by Google Scholar, DOAJ, BASE, and EBSCO.
Articles 531 Documents
An ultra-broadband microstrip antenna using a triple dumbbell-shaped defected ground structure Haryanto, Puji; Astuti, Dian Widi; Alaydrus, Mudrik; Firdausi, Ahmad; Rusdiyanto, Dian; A Majid, Huda
SINERGI Vol 30, No 1 (2026)
Publisher : Universitas Mercu Buana

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22441/sinergi.2026.1.008

Abstract

Microstrip antennas are widely used in modern communication systems due to their compact size and low profile. However, they typically suffer from narrow bandwidth, limiting their performance in advanced wireless applications. This study addresses this limitation by employing a triple dumbbell-shaped defected ground structure (DGS). The antenna is designed to operate at 3.5 GHz using a Rogers RT5880 substrate, and its performance was analyzed through simulations in HFSS 15.0 software. Without the DGS, the antenna exhibits a fractional bandwidth (FBW) of only 1.71%, operating from 3.47 GHz to 3.53 GHz. Incorporating the triple dumbbell-shaped DGS in the ground layer increases the FBW significantly to 53.6%, extending the operating frequency range from 2.39 GHz to 4.14 GHz. This improvement was achieved through the careful optimization of DGS parameters. The simulated gain at 3.5 GHz is 5.13 dBi. The proposed design demonstrates superior performance compared to conventional techniques such as split-ring resonators (SRR) and Butler matrix (BM) configurations. Simulation and measurement results show excellent agreement, validating the design. The achieved ultra-wideband performance benefits 5G and next-generation systems, offering greater frequency tolerance, diverse signal support, increased capacity, and reliable operation, making the antenna a promising candidate for future wireless applications. 
Towards low-carbon ammonia: simulation and economic evaluation of blue ammonia with carbon utilization Pratiwi, Vibianti Dwi; Kunup, Sukmawati; Aulia, Nada Rahma; Hasan, Helmi Sayid; Suhartono, Jono
SINERGI Vol 30, No 1 (2026)
Publisher : Universitas Mercu Buana

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Abstract

The proposed blue ammonia production considers technical, environmental, and economic aspects. The design of the blue ammonia using CCUS (Carbon Capture, Utilization, and Storage) technology in this study contributes to reducing carbon emissions and providing a more environmentally friendly ammonia supply in East Java, Indonesia, due to the availability of raw materials and geological storage locations for CO2 storage. Technically, the blue ammonia production was simulated with Aspen Hysys V.14.0. uses the Kellogg process, where the ammonia converter operates at a temperature of 437.60 °C and a pressure of 141.9 bar. From the environmental aspect, as much as 68.34 tons/h of ammonia produced produces CO2 71.36 tons/h, which is a total emission of 1.06 tons CO2/ tons NH3. In this study, CO2 delivery with a pipe length of 85 km  (ID:539.8mm; OD: 558.7mm) was simulated using default parameters in Aspen Hysys V.14.0. In economic calculations from APEA (Aspen Process Economic Analyzer), the manufacture of blue ammonia designed in this study is very large, with a TAC (Total Annual Cost) of $82.25x106/year and an LCOA (Levelized Cost of Ammonia) of $93.28x108/ tons NH3. This study demonstrates the integration of CCUS technology into ammonia production, resulting in a reduction of CO₂ emissions by 1.06 tons CO₂ per ton of ammonia produced. The proposed system provides a practical approach for improving the environmental sustainability of industrial chemical processes.
Use of activated carbon from NiO modified Polyethylene Terephthalate plastic bottle waste to optimize natural gas storage in Adsorbed Natural Gas (ANG) technology Yuliusman, Yuliusman; Kamilia, Athaya Khanza; Utomo, Anggi Nugroho; Nasruddin, Nasruddin
SINERGI Vol 30, No 1 (2026)
Publisher : Universitas Mercu Buana

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Abstract

Storage and transportation of natural gas are major challenges in optimizing energy use. To overcome the challenges, Adsorbed Natural Gas (ANG) technology offers a promising alternative for increasing storage capacity at lower pressures. Therefore, this study aims to explore the efficiency of waste polyethylene terephthalate (PET) bottles converted into activated carbon through pre-treatment, carbonization, chemical activation with 4 M KOH, and physical activation using N₂ flow. Modification of activated carbon was carried out using NiO metal impregnation at concentrations of 0.5%, 1%, and 2% to enhance adsorption performance. The results of characterization using iodine number, scanning electron microscopy (SEM), and energy dispersive X-ray spectroscopy (EDS) showed that the 2% NiO-impregnated sample had the highest surface area of 997.65 m²/g. Natural gas adsorption and desorption testing showed that this material achieved the maximum storage capacity of 138.9 g/kg at 28°C and 9 bar, with superior performance compared to non-impregnated samples and several previously reported ANG adsorbents. These results showed that combining NiO modification with KOH-activated PET waste improved methane uptake beyond commercial activated carbons and provided an environmentally sustainable solution for plastic waste valorization. 
Land cover changes, built-up and vegetation density, and the Urban Heat Island (UHI) phenomenon in Pekanbaru City Sari, Meassa Monikha; Dewi, Atri Prautama; Lestari, Valdya Hartati; Deviro, Sonya Okta
SINERGI Vol 30, No 1 (2026)
Publisher : Universitas Mercu Buana

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22441/sinergi.2026.1.004

Abstract

Pekanbaru city has a high population growth rate and is currently experiencing rapid urbanization, which is driving urban expansion. Urban development alters land cover patterns and reduces environmental quality. The development of residential areas and infrastructure reduces vegetation, affecting Land Surface Temperature (LST) and contributing to the emergence of the Urban Heat Island (UHI) phenomenon. This study aims to analyze changes in land cover, examine the correlation between LST and the Normalized Difference Built-up Index (NDBI) and the Normalized Difference Vegetation Index (NDVI), and then investigate the UHI phenomenon in Pekanbaru City. The research method is quantitative, using data from Pekanbaru City, an administrative map, and Landsat 8 OLI/TIRS imagery, which were spatially analyzed in ARGIS and QGIS. The novelty is the use of guided classification and maximum likelihood algorithms for land cover classification, which revealed significant changes over the five years from 2018 to 2023 in Pekanbaru City. Over 5 years, land cover in the city of Pekanbaru changed, with water bodies increasing by 23%, palm areas increasing by 5%, built-up areas increasing by 34%, and vegetation increasing by 10%, while bare land decreased by 57%. There are significant changes in built-up and vegetation density. The correlation between land surface temperature and built-up density is positive; however, it is negatively correlated with vegetation density. There is an urban heat island phenomenon in Pekanbaru City, characterized by surface temperatures exceeding the UHI threshold. 
Towards enhanced acoustic fan booster damage detection: a comparative study of feature-based and machine learning approaches Youlia, Rikko Putra; Romahadi, Dedik; Feleke, Aberham Genetu; Nugroho, Irfan Evi; Alina, Alina
SINERGI Vol 30, No 1 (2026)
Publisher : Universitas Mercu Buana

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Abstract

Machine failure detection frequently uses non-destructive monitoring techniques such as vibration analysis. Although vibration analysis can identify machine degradation, the apparatus is often costly and necessitates specialist knowledge. Additionally, many existing methods in audio classification rely on characteristics represented as pictures or vectors, which increases computational complexity. In contrast, this research introduces a novel method that substitutes vibration data with a singular numerical feature derived from audio signals, addressing both cost and complexity issues. Our objective is to develop a rapid and precise audio-based method for detecting machine damage. The acoustic signals from the machine apparatus were classified into three categories: normal, belt damage, and combined belt and bearing defect. The data processing technique involved lowering the sample rate and segmenting the data to improve computational efficiency and classification performance. We use the Welch method and appropriate statistical techniques to analyze Power Spectral Density (PSD). The performance of seven classifier models, KNN, LDA, SVM, NB, ANN, RF, and DT, was evaluated using accuracy, precision, sensitivity, specificity, and F-score. LDA achieved the highest accuracy at 92.83%, followed by ANN (92.75%), NB (92.74%), and DT (92.34%). These models outperformed KNN (89.90%) and RF (89.40%), with SVM recording the lowest accuracy at 85.40%. LDA was highly effective, achieving the highest accuracy with a single average PSD-type feature, showcasing its robustness in machine defect diagnosis. Compared to previous methods, this approach simplifies feature extraction, reduces computational demands, and maintains high diagnostic performance, providing notable benefits in terms of effectiveness and precision. 
Experimental investigation of PWHT and normalizing effects on SMAW low-carbon steel joint properties Manik, Parlindungan; Firdhaus, Ahmad; Prasetya, Blinka Hernawan; Prayoga, Rhizky
SINERGI Vol 30, No 1 (2026)
Publisher : Universitas Mercu Buana

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22441/sinergi.2026.1.009

Abstract

The influence of post-weld heat treatment (PWHT) followed by normalizing on the mechanical properties of AH36 low-carbon steel is significant, particularly in the context of marine applications, such as shipbuilding welded joints. According to the extant literature, PWHT has been demonstrated to reduce residual stresses and enhance microstructural uniformity. However, the suitable PWHT temperatures for AH36 steel welds to balance strength, ductility, and toughness prior to normalizing remain underexplored. The objective of this study is to ascertain the suitable PWHT temperatures prior to normalizing, with the aim of improving weld performance in marine environments. A parametric study was conducted on AH36 steel specimens welded using shielded metal arc welding. The specimens were subjected to PWHT at 0°C (as-welded), 450°C, 600°C, and 750°C, followed by normalizing. Tensile, bending, and Charpy impact tests were utilized to assess the mechanical properties against established maritime safety standards. The results show that 600°C is the optimal PWHT temperature, effectively reducing residual stresses and promoting microstructural homogeneity. This, in turn, ensures that welds meet safety standards while preserving mechanical integrity. Higher temperatures increased the risk of brittleness, while lower temperatures provided insufficient stress relief. This study demonstrates that precise selection of PWHT temperature prior to normalizing is critical for ensuring reliable welds in marine structures. It identifies the optimal condition that maximizes strength, ductility, and impact toughness of AH36 steel while satisfying the Indonesian Classification Bureau (BKI) maritime safety standards. 
The effect of different levels of cleanness of the pre-coat surface on adhesion and corrosion performance of A36 steel with epoxy coating Widodo, Teguh Dwi; Setyarini, Putu Hadi; Sugiarto, Sugiarto; Raharjo, Rudianto; Bintarto, Redi; Darmadi, Djarot Bangun; Sagita, Sagita
SINERGI Vol 30, No 1 (2026)
Publisher : Universitas Mercu Buana

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22441/sinergi.2026.1.010

Abstract

Adhesion and corrosion protection are the main properties of epoxy coatings, especially when applied to materials exposed to harsh environments, such as chloride-containing water. However, the adhesion and corrosion protection of coatings are affected by surface preparation, especially the cleanliness of the substrate surface prior to coating application. Choosing the proper surface preparation can optimize the coating's capabilities. This research aims to evaluate the Effect of blasting process cleanliness on coating performance on the steel surface. The novel approach is to correlate NACE surface cleanliness standards with coating performance. In this study, A36 steel is used. The cleaning procedure uses an air-blasting process with an 8-bar nozzle pressure and at least 5 minutes of spraying time to meet the desired National Association of Corrosion Engineers (NACE) standard. The abrasive utilizing garnet with a mesh of 30-40. Meanwhile, coating is performed at room temperature using the airless spray method with a 90° angle, a distance of 25 cm from the substrate and the nozzle, and a nozzle speed of 300 mm/s. The gap in the coating process between the first and second layers is 24 hours. The results showed that surface preparation influenced the coating's pullout strength and corrosion performance. The pullout strength test demonstrated that NACE 2 provided the highest pullout strength. Likewise, corrosion rate testing showed that surface preparation affects the corrosion rate, with NACE 1 providing the lowest corrosion rate (the best corrosion protection). 
Stress-Strain Behavior and Residual Strength of Petobo Sand with Variable Fines Content after the 2018 Palu Liquefaction Vidayanti, Desiana; Rahardjo, Paulus Pramono; Nazir, Ramli
SINERGI Vol 30, No 1 (2026)
Publisher : Universitas Mercu Buana

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Abstract

Liquefaction was one of the main causes of severe ground deformation during the 2018 Palu earthquake, particularly in the Petobo area where large-scale flow liquefaction occurred. Despite extensive field investigations, no laboratory-based residual shear strength data for Petobo soil have been available to explain the exceptional mobility of the flowslide. This study investigates the stress–strain response and residual strength of Petobo silty sand containing different proportions of fines through monotonic Consolidated Undrained (CU) triaxial tests. Reconstituted specimens were prepared using the moist tamping method with fines contents of approximately 9% and 26.4%, and tested under three levels of initial mean effective stress.The higher-fines specimen generated excess pore water pressure more rapidly and showed stronger contractive behavior at small strains. However, at larger strains, the 26.4% fines specimen mobilized greater residual strength, expressed as the ratio of residual deviator stress to initial mean effective stress (0.79-0.94), compared with the 9% fines specimen (0.85-0.89). These results indicate that fines increase contractive tendency during initiation but enhance resistance against large post-liquefaction deformation. The influence of fines on post-liquefaction behavior is therefore nonlinear and dependent on deformation stage and initial density. This study provides the first laboratory-based residual strength data of Petobo silty sand within the Critical State Soil Mechanics framework, clarifying its post-liquefaction resistance characteristics. The findings improve understanding of flow behavior in silty sands, offer mechanistic insight into the 2018 Petobo failure, and supply essential parameters for calibrating constitutive models and supporting liquefaction hazard mitigation in similar alluvial deposits in Central Sulawesi
Utilization of teak wood powder waste as eco-friendly filler in HRS-WC asphalt: a comparative analysis of dry and wet Marshall mix methods Machsus, Machsus; Mawardi, Amalia Firdaus; Basuki, Rachmad; Hadi, Achmad Faiz; Islamey, Annizza Putri; Ndruru, Kornelius Sofinner; Wirawan, Arkaan Fadhiilah
SINERGI Vol 30, No 1 (2026)
Publisher : Universitas Mercu Buana

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Abstract

With the increasing demand for road durability driven by rapid economic development, innovative and sustainable approaches are essential to improve the strength and service life of road pavements. This study investigates the use of teak wood powder waste (TWPW) as a cost-effective and environmentally friendly filler material in Hot Rolled Sheet – Wearing Course (HRS-WC) asphalt mixtures. Utilizing bio-waste not only supports circular economic principles but also offers economic benefits by reducing the reliance on conventional and more expensive fillers. The research evaluates various TWPW concentrations (0%, 0.3%, 0.6%, and 0.9%) and their effects on key Marshall test parameters, including stability, flow, Marshall Quotient (MQ), Voids in Mineral Aggregate (VMA), Voids in Mix (VIM), and Voids Filled with Asphalt (VFA). Samples were prepared using both dry and wet methods in accordance with Bina Marga (2018) specifications. The results indicate that the optimum filler content was 0.9% for the dry method (stability: 1042.68 kg) and 0.6% for the wet method (stability: 1161.14 kg). SEM analysis confirmed that filler dispersion significantly influences the internal structure and porosity of the mixture. At 0.3% and 0.6%, the filler was more evenly distributed, leading to improved compaction and mechanical performance. Conversely, agglomeration at 0.9% increased voids and reduced compaction quality. This study demonstrates that TWPW can serve as a viable low-cost filler alternative, maintaining pavement performance while reducing material costs and environmental impact. The findings support the adoption of sustainable waste utilization practices in road construction.
Sustainable competitiveness through community empowerment and the success factors of SMEs? Kartika, Hayu; Hardjomidjojo, Hartrisari; Machfud, Machfud; Warsiki, Endang
SINERGI Vol 30, No 1 (2026)
Publisher : Universitas Mercu Buana

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22441/sinergi.2026.1.005

Abstract

This study aims to examine the relationship between sustainable competitiveness and community empowerment in the context of small and medium enterprises (SMEs) by conducting a systematic literature review using the PRISMA guidelines. The review identified relevant studies published between 2021 and 2025 in the Scopus database and analyzed them using the VOS Viewer bibliometrics tool. This study explores the role of empowerment in improving Sustainable Competitiveness. Findings show that the topics of sustainable competitiveness and community empowerment are still rarely discussed in an integrated manner, although both are significantly interrelated. The analysis identified six main dimensions that contribute to sustainable competitiveness in SMEs: Economic, Social, Environmental, Technological, Organizational, and Human Resources that correlate with sustainable competitiveness in SMEs. In various literature, sustainable competitiveness in SMEs is often discussed and has a close relationship with the use of technology in SMEs businesses. However, on the other hand, it also needs to be supported by the role of the community, which is included in the social dimension, which also plays an important role in SMEs that support business sustainability, foster cooperation networks, and improve the welfare of local communities. These findings provide a basis for insight and information to develop targeted business strategies and public policies aimed at enhancing sustainable competitiveness in SMEs through community engagement.