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Makara Journal of Technology
Published by Universitas Indonesia
ISSN : 23552786     EISSN : 23564539     DOI : https://doi.org/10.7454/mjt
Core Subject : Science, Engineering,
Chemical Engineering, Chemistry & Bioengineering Civil Engineering, Building, Construction & Architecture Electrical & Electronics Engineering Engineering Materials Science & Nanotechnology Mechanical Engineering
MAKARA Journal of Technology is a peer-reviewed multidisciplinary journal committed to the advancement of scholarly knowledge and research findings of the several branches of Engineering and Technology. The Journal publishes new results, original articles, reviews, and research notes whose content and approach are of interest to a wide range of scholars. It also offers rapid dissemination. MAKARA Journal of Technology covers the recent research in several branches of engineering and technology include Electrical & Electronics Engineering, Computer Engineering, Mechanical Engineering, Chemical & Bioprocess Engineering, Material & Metallurgical Engineering, Industrial Engineering, Civil & Architecture Engineering, and Marine Engineering. Criteria used in determining acceptability of contributions include newsworthiness to a substantial part of the engineering & technology and the effect of rapid publication on the research of others. This journal, published three times each year, is where readers look for the advancement of discoveries in engineering and technology.
Arjuna Subject : Teknik (semua kategori) - Teknik (Lain-Lain)
Articles 494 Documents
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Computational Fluid Dynamics (CFD) Modeling for Bio-Inspired Aerodynamic Optimization in Autonomous Drones Unegbu, Hyginus C.O.; Yawas, Danjuma Saleh
Makara Journal of Technology Vol. 29, No. 2
Publisher : UI Scholars Hub

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Abstract

This study explores the aerodynamic benefits of bio-inspired design modifications for autonomous drones using advanced Computational Fluid Dynamics (CFD) simulations. Four bio-inspired configurations—leading-edge serrations, winglets, riblet surfaces, and curved wings—were assessed and compared against a baseline drone model to evaluate their impact on aerodynamic performance. The results indicated that all bio-inspired designs significantly enhanced lift, reduced drag, and improved overall aerodynamic efficiency. The leading-edge serration configuration achieved the highest performance gains, with a 33.6% increase in maximum lift coefficient (CL) and a 29.5% improvement in lift-to-drag ratio (CL/CD), primarily due to delayed flow separation and reduced turbulence. Winglets minimized wingtip vortices, leading to an 18.3% reduction in drag coefficient (CD) and improved lift efficiency. Riblet surfaces moderately decreased drag by streamlining boundary layer flow, while the curved wing design enhanced stability and manoeuvrability at high angles of incidence. These findings demonstrate the potential of bio-inspired designs to optimize drone performance, extending their operational range and adaptability across varying flight conditions. The study provides valuable insights for development of next-generation UAVs, offering a pathway to improved energy efficiency, flight stability, and versatility in diverse operational environments.
Assessing Solar Radiation Patterns in Sarawak using Measured Data and the Hargreaves-Samani Model for Photovoltaic Systems Application Soo, Chun Yong; Chan, Xian Hwa; Wan Mokhtar, Wan Mohamad Husni; Mohd Rais, Ahmad Rujhan
Makara Journal of Technology Vol. 29, No. 2
Publisher : UI Scholars Hub

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Abstract

This study evaluates the Hargreaves-Samani model for estimating solar radiation in five locations in Sarawak: Bintulu, Kapit, Sri Aman, Kuching, and Miri (Subis), using minimum and maximum temperatures as key inputs. Analysis reveals stable minimum temperatures (19.7 °C to 28.8 °C), supporting consistent solar radiation patterns favorable for Photovoltaic (PV) performance. Miri (Subis) recorded the highest daily maximum temperature of 44.8 °C, while Kuching had the lowest at 24.7 °C, highlighting significant regional climatic variability. Analysis also indicates strong solar potential in Bintulu, Kapit, Sri Aman, Kuching, and Miri, with radiation peaking at 7.5 kWh/m², though seasonal variations impact PV power generation. Initial solar radiation, RI estimates range from 2.49 to 7.81 kWh/m² annually, demonstrating substantial seasonal and regional differences. Re-optimized adjustment coefficients (k) indicate that Bintulu (0.190) and Kuching (0.186) exceed coastal standards (0.16), while Kapit (0.168), Sri Aman (0.175), and Miri (0.160) are below inland standards (0.19). These adjustments yield optimized solar radiation, RO values ranging from 2.15 to 7.351 kWh/m², confirming significant PV potential. Cloud cover varies from 20.3% to 100%, peaking during monsoon seasons and decreasing in drier months. The Hargreaves-Samani model demonstrated the highest accuracy in Sri Aman (RMSE: 29.63%) and Kapit (RMSE: 32.76%), with lower accuracy in Bintulu (RMSE: 59.34%) when comparing measured and optimized solar radiation. These findings provide valuable insights for enhancing solar energy utilization and optimizing PV systems in Sarawak’s tropical climate.
Direct Control Strategy using Polynomial Fuzzy-Based Adaptive Fractional Order PID Controller Rospawan, Ali; Angelina, Clara Lavita; Samsuri, Faisal; Baihaqi, Muhammad Yeza; Halawa, Edmun; Munajat, Muhammad; Vincent, Vincent; Setiyadi, Surawan; Purnama, Irwan; Simatupang, Joni Welman
Makara Journal of Technology Vol. 29, No. 2
Publisher : UI Scholars Hub

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Abstract

This paper presents a novel direct control strategy using a polynomial fuzzy neural network-based adaptive fractional order proportional integral derivative (PFNN-AFOPID) controller for nonlinear and time-varying systems. The proposed approach integrates the enhanced flexibility of fractional order calculus PID with the superior nonlinear approximation capabilities of polynomial fuzzy models, enabling dynamic adjustment of all control parameters without requiring precise mathematical modeling of system dynamics. By extending traditional PID control with fractional-order operations, the controller achieves improved frequency response and robustness against disturbances. Experimental validation on a DC motor position control system demonstrates significant performance improvements. Compared to traditional PID, the proposed PFNN-AFOPID achieved a performance improvement of 53.69% in RMSE, 78.56% in ISE, 69.92% in IAE, and 83.98% in ITAE. When compared to the existing fuzzy neural network-based adaptive PID (FNN-APID), our approach delivered improvements of 21.06% in RMSE, 28.79% in ISE, 5.69% in IAE, and 32.86% in ITAE. These results confirm the superior capability of the proposed approach in handling system nonlinearities while maintaining precise control under varying operational conditions, without requiring prior system dynamics knowledge or extensive offline training.
Effect of Contact Time and Concentration on Adsorption of Pb2+Metal Ion Utilizing Crab Shell Chitosan and Activated Bentonite Clay Composite Sasria, Nia; Wisaka, Adi; Yusariarta Putra Parmita, Ade Wahyu; Nur Tajalla, Gusti Umindya
Makara Journal of Technology Vol. 29, No. 2
Publisher : UI Scholars Hub

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Abstract

Indonesia produced 1,508 tons of nonliving crabs in the January–March 2020 period. The number of shells generated can account for 40%–60% of the overall weight. Therefore, using crab shells made into chitosan is expected to increase the economic value and reduce waste from crab shells. Chitosan can be modified with clay previously activated with an acid solution to form a chitosan–clay composite to improve the adsorption capacity. This study aims to analyze the differences in characteristics between chitosan and clay before and after the immobilization process. A comparison of chitosan and clay (1:2) is conducted on the basis of variations in the contact time for 5, 30, 55, and 80 min and in the concentration of metal solution as much as 10, 30, and 50 ppm. The results of the Fourier transform infrared spectroscopy (FTIR) study found stretching vibrations of –NH originating from the chitosan structure, as well as several functional groups from clay, such as silanol (Si–OH) and siloxane (Si–O–Si). The results of the X-ray diffraction (XRD) test show that the clay used was bentonite clay. Meanwhile, the scanning electron microscopy (SEM) and surface area analyzer (SAA) test results show that the chitosan–clay adsorbent has a rougher and hollower surface with a surface area of 23,666 m2/g. The best adsorption percentage of 90.59% occurred at a concentration of 10 ppm with a contact time of 30 min.
Determination of Excess Pore Pressure in Under Consolidating Soil by using CPTu Ihut, Karolina Villa Delfia; Wijaya, Martin; Lim, Aswin; Satyanaga, Alfrendo; Aglia, Grisella; Syifanaya, Sharfina Faradiba; Sugianto, Andy
Makara Journal of Technology Vol. 29, No. 2
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Abstract

North Jakarta is predominantly composed of soft soil that is still undergoing consolidation. According to research by Raharjo et al. (2022), excess pore pressure is still present in the soils of Jakarta. The degree of consolidation and excess pore pressure values indicate that consolidation is not yet complete (Raharjo et al., 2022). In this study, the researchers developed two methods to determine excess pore pressure using field testing. The Stress History and Normalized Soil Engineering Properties (SHANSEP) model equation from Ladd and Foot (1974), as well as Finite Element Method (FEM) modeling using the PLAXIS program, were utilized to estimate the excess pore pressure in the soil. The results from the SHANSEP-based analysis were then compared with those from the FEM analysis using PLAXIS. The comparison showed that the excess pore pressure estimated using PLAXIS closely matched the values obtained from CPTu tests based on the SHANSEP model. Interpretation of parameters from the Cone Penetration Test with pore pressure measurement (CPTu) indicates that the soil at the project site is still consolidating and undergoing settlement. Similarly, the settlement results from the PLAXIS analysis support this conclusion.
Control Strategies for 6-DOF Quadcopter UAVs: Cascade PID Stabilization in White Noise Conditions Van, An Vo; Duy, Hung Ha
Makara Journal of Technology Vol. 29, No. 3
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In this study, a cascade PID control structure is proposed and implemented for a 6-degree-of-freedom (6-DOF) unmanned aerial vehicle (UAV) to enhance stability and trajectory tracking capabilities under both noise and non-noise conditions. The controller was designed based on the Tyreus–Luyben tuning method and was evaluated using quantitative metrics, including rise time, settling time, overshoot, and steady-state error. Simulation results on MATLAB/Simulink show that the controller achieves high performance in angular channels (ϕ, θ, ψ) and altitude (z) with a short rise time (< 2s), slight overshoot (< 1%), and nearly eliminated steady-state error. However, the horizontal position channels (x, y) have a longer settling time (~110s) and are sensitive to white noise. Quantitative comparisons with other control methods show that the cascade PID outperforms the standard PID in terms of accuracy and stability, achieving a performance comparable to LQR under noise-free conditions, but is less robust in the presence of noise than advanced methods like SMC and MPC. These results confirm the feasibility of cascade PID in UAV applications and indicate potential future improvements by integrating nonlinear, adaptive, or intelligent control strategies.
Helical Coil Compression Spring Retrofit Design of Wheelbarrow for Optimal Load Carrying Effectiveness Agbo, Cornelius Ogbodo Anayo
Makara Journal of Technology Vol. 29, No. 3
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Wheelbarrows are essential multipurpose and dual-function materials handling equipment for many industries and homes. They find exclusive use in the movement of finished goods and raw materials where no other form of transportation works. However, the traditional wheelbarrows require enormous human effort to accomplish the task of conveying a reasonable amount of load from one place to another. During the process, shock loads from road irregularities are transmitted directly to the Barrow pusher. Therefore, this study investigated a retrofitted helical coil, compression spring, wheelbarrow design for effective load transportation. A wheelbarrow with a trapezoidal bucket capacity of 50 l was fabricated and mounted on a hollow pipe galvanized steel chassis frame. The bucket was supported on the front end of the frame using two helical coil compression springs to cushion the shock loads transmitted to the Barrow pusher. For a 150-kg payload, three standard bags of cement equivalent, and a deadweight of 22kg, the spring retrofit design wheelbarrow effectively reduces the galloping shocks through bumps and other path surface irregularities better than conventional non-spring wheelbarrows. The new design can therefore provide succor to the regular wheelbarrow pushers who tend to develop unintended health issues, such as muscular build-up and cramps, as they use a wheelbarrow to move materials over a distance.
Aerodynamics and Heat Transfer in Polymer Blown Film Processing: Experimental and Numerical Investigation Zulbakri, Mohammad Luqman; Mat. Rautin, Nur Atiqah; Shuib, Raa Khimi; Ku Ishak, Ku Marsilla; Abdul Hamid, Auratus Zuratul Ain; Shafiq, Mohamad Danial; Idroas, Mohamad Yusof; Abdullah, Muhammad Khalil
Makara Journal of Technology Vol. 29, No. 3
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The effects of airflow dynamics, heat transfer, and mechanical properties on the HDPE blown film extrusion process were examined using a single-lip air ring with a fixed compressed-air valve opening angle of 10°. Reynolds numbers ranging from 9175 to 25911 were analyzed to understand their impact on cooling efficiency, bubble morphology, and film properties. Numerical simulations employing the Standard k−ω turbulence model in ANSYS FLUENT v2023, with mesh refinement achieving y+ ≈ 1, captured detailed flow and heat transfer behavior. Results showed that higher Reynolds numbers significantly enhanced the heat transfer coefficient, with values increasing from 1096 W/m²·K at Reynold number of 9175 to 1438 W/m²·K at Reynolds number of 25911, reducing the axial cooling distance by up to 30%. This rapid cooling improved the cooling rate but led to a reduced lay-flat width (from 29.10 cm at a Reynolds number of 9175 to 27.50 cm at a Reynolds number of 25911) and thicker films. The tensile stress decreased from 25.25 MPa at a Reynolds number of 9175 to 20.84 MPa at a Reynolds number of 25911, reflecting the impact of turbulence on the polymer chain alignment. These findings emphasize the trade-offs between enhanced cooling efficiency and material properties, offering critical insights for optimizing blown film extrusion processes for improved quality and operational performance.
Dual-Interface WiFi Packet Sniffer System using ESP32-CAM with Real-Time PCAP Generation for IoT Network Analysis Setiawan, Boy, Boy; Maulani, Maghfiroh; Pratama Putra, Zico; Senoyodha Brennaf, Muhammad
Makara Journal of Technology Vol. 29, No. 3
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This study focuses on designing and implementing a cost-effective and energy-efficient WiFi packet sniffer system using the ESP32. The ESP32-CAM module, which combines WiFi, Bluetooth, and microSD support, is used to capture IEEE 802.11 frames in real-time via promiscuous mode. Packets are stored in packet capture format, which is compatible with tools such as Wireshark and Scapy. Developed using the official ESP-IDF, it offers low-level control and high performance. Two user interfaces were implemented: a UART-based text menu and a web-based HTTPS menu hosted on the ESP32 itself. Functional and performance evaluations were conducted with a focus on capturing broadcast and management frames without payload decryption. The system achieves 99.99% packet capture accuracy at 500,000 packets with a total hardware cost of $25 and power consumption of 2.1 W during active capture, representing a 95% cost reduction and 80% power savings compared to commercial alternatives. The download and file-listing speeds through the web-based menu were also evaluated, revealing that the system performs optimally with fewer files but experiences interruptions during large-scale operations. The proposed system provides a lightweight, standalone, and highly portable alternative to conventional packet sniffing tools despite the limitations in encryption handling and resource constraints. This makes it suitable for educational, diagnostic, and preliminary network analysis, particularly in low-power scenarios.
Prediction of Maximum Local Scour Depth Due to Horizontal Jets of Flushing Gate using Artificial Neural Network Kurniawan, Adhy; Sulaiman, Muhammad; Maryono, Agus; Kironoto, Bambang Agus; Hazhiyah, Amalia Ula
Makara Journal of Technology Vol. 29, No. 3
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Local scour is a serious concern for hydraulic engineers. To maintain the reservoir capacity, flushing accumulated sediment is necessary, resulting in a turbulent and scouring jet from the flushing gate. Predicting the maximum scour depth from these water jets is crucial for civil engineers. Despite many proposed equations, one have shown consistent applicability due to the complex nature of the process. Ensuring accurate prediction between hydraulic parameters and the geometry of the scour hole in prototype experiments remains a key issue. To address this issue, this paper examines the use of artificial neural network (ANN) analysis as a computing device for predicting the maximum local scour depth due to horizontal water jets. The neural network is developed using the data collected from previous experiments and an ongoing study. This paper selected four dimensionless parameters as the key variables: the densimetric Froude number (Frd), the relative roughness (d50/hv), the submergence (ht/hv), and the dimensionless apron length or the length of bed protection (La/hv). This paper describes the development of a feed-forward neural network trained by back-propagation for modeling. This study indicates that the ANN is an effective tool for accurately predicting the scour depth.

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