Article Per Year (5 Year)
p-Index From 2021 - 2026
0.408
P-Index
This Author published in this journals
All Journal Mechanical Engineering for Society and Industry Automotive Experiences
Abdul Mudjib Sulaiman Wahid
Nanyang Technological University, Singapore
Aerospace Engineering Automotive Engineering Chemical Engineering, Chemistry & Bioengineering Control & Systems Engineering Electrical & Electronics Engineering Energy Engineering Industrial & Manufacturing Engineering Materials Science & Nanotechnology Mechanical Engineering Transportation

Published : 2 Documents Claim Missing Document
Claim Missing Document
Check
Articles

Found 2 Documents
Search

 1 
Probabilistic Performance Prediction of a Hydrogen-Converted SI Engine Using a Markov-Chain-Wiebe Framework Purnami; Willy Satrio Nugroho; Lilis Yuliati; Fikrul Akbar Alamsyah; Abdul Mudjib Sulaiman Wahid; I Nyoman Gede Wardana
Automotive Experiences Vol. 9 No. 1 (2026)
Publisher : Universitas Muhammadiyah Magelang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.31603/ae.15544

Abstract

This study employs a novel Markov-chain modeling framework to analyze the combustion-performance interaction in a hydrogen-fueled spark-ignition engine. The methodology integrates a Wiebe heat-release model within a Markov-chain state-transition framework, where each discrete engine state defines combustion parameters and probabilistic transitions capture cycle-to-cycle variability. Results demonstrate that engine behavior is dominantly governed by combustion phasing, with spark timing exerting primary control over torque, efficiency, and brake-specific fuel consumption (BSFC). Sensitivity analysis confirms spark timing produces the steepest performance gradients, while ignition voltage offers secondary benefits and engine speed exhibits minimal influence. The model reveals a highly nonlinear torque response to spark advance, characterized by a rapid rise culminating in a narrow maximum brake torque (MBT) plateau at 8°–10° BTDC, corresponding to a distinct BSFC minimum. Significant data scatter underscores the stochastic nature of hydrogen combustion, arising from multidomain interactions between air-fuel ratio, ignition strength, and phasing. The Markov-chain approach successfully captures this coupled deterministic-probabilistic behavior, highlighting the critical need for precise spark-timing control to optimize performance in hydrogen applications.
Flash joule heating synthesis of porous graphene oxide from banana leaf waste for high-performance supercapacitor electrodes Ikhwanul Qiram; Dewi Sartika; Wisnu Kuncoro; Willy Satrio Nugroho; Abdul Mudjib Sulaiman Wahid
Mechanical Engineering for Society and Industry Vol. 6 No. 1 (2026): Issue in Progress
Publisher : Universitas Muhammadiyah Magelang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.31603/mesi.14658

Abstract

This study investigates the synthesis of porous graphene oxide (GO) derived from banana leaf waste using the Flash Joule Heating (FJH) method for supercapacitor electrode applications. Carbonization was conducted at input voltages of 5, 10, and 15 VA for 2 s, followed by activation with 0.3 M KOH. Structural characterization (SEM, EDX, FTIR, and XRD) confirmed the formation of hierarchical porous carbon with oxygen-containing functional groups. Electrochemical evaluation revealed that the sample synthesized at 10 VA exhibited the best performance, achieving a specific capacitance of 345 F g⁻¹, low internal resistance of 0.65 Ω, and capacitance retention of 95% after 500 cycles. In contrast, the 5 VA sample showed lower conductivity due to its amorphous structure, while the 15 VA sample exhibited reduced capacitance due to excessive macropore formation. These results demonstrate that controlled FJH voltage plays a critical role in optimizing pore structure and electrochemical performance, highlighting banana leaf-derived GO as a promising and sustainable electrode material for high-performance supercapacitors.
Co-Authors Dewi Sartika Fikrul Akbar Alamsyah I Nyoman Gede Wardana Ikhwanul Qiram Lilis Yuliati Purnami Willy Satrio Nugroho Wisnu Kuncoro