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Review on Dynamic Behaviour of Moored Twin Hulls FPSO Nik Ismail, Nik Mohd Khairuddin B.; Koto, Jaswar
Journal of Ocean, Mechanical and Aerospace -science and engineering- Vol 14 No 1 (2014): Journal of Ocean, Mechanical and Aerospace -science and engineering- (JOMAse)
Publisher : International Society of Ocean, Mechanical and Aerospace -scientists and engineers- (ISOMAse)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.36842/jomase.v14i1.466

Abstract

The development of floating offshore structures have been successfully and rapidly in many years. Many researchers has studied the dynamic behavior of of moored floating production storage and offloading structure. This paper investigated the dynamic behavior of catenary anchor leg moored twin hulls floating production storage and offloading which subjected to sea waves, in order to get insight knowledge on its dynamic behaviours due to various turret locations with different loading conditions. The comparison of the dynamics behaviour to the FPSO and it mooring lines are important when choosing potential development and optimal options. The research founded that it currently no information is available for the comparison of the dynamic behaviour of the internal turret moored of twin hulls FPSO at different loading conditions with various turret locations under the action of wave.
Initial Imperfection Design of Subsea Pipeline to Response Buckling Load Junaidi, Abdul Khair; Koto, Jaswar
Journal of Ocean, Mechanical and Aerospace -science and engineering- Vol 15 No 1 (2015): Journal of Ocean, Mechanical and Aerospace -science and engineering- (JOMAse)
Publisher : International Society of Ocean, Mechanical and Aerospace -scientists and engineers- (ISOMAse)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.36842/jomase.v15i1.462

Abstract

Oil and gas transportation in subsea operation continues to the extreme depth. Harsh environment in deep water lead to a challenge for especially pipeline design. The pipelines are operated at high pressure and high temperature in order to be able to transport the crude oil from the well to the end termination of loading. Such condition, the pipelines are subjected to axial compressive forces which will cause the pipelines to expand, consequently the pipelines tend to buckle for certain size and distance from the initial of pipeline. The sleeper is one of method to control the pipeline expansion by insertion of bar underneath the pipeline. The sleeper results initial imperfection for pipeline which forms a curvature. The magnitude of curvature is designed comply with DNV OS F101 where the design load will accommodate the combination load works on pipeline and the curvature configuration will validate by using ANSYS 14.
Air Flow Characteristics and Behaviour of Main Rotor Blade of Remote Controlled Model Scale Helicopter Ammoo, Mohd. Shariff bin; Awal, Ziad Bin Abdul; Koto, Jaswar
Journal of Ocean, Mechanical and Aerospace -science and engineering- Vol 16 No 1 (2015): Journal of Ocean, Mechanical and Aerospace -science and engineering- (JOMAse)
Publisher : International Society of Ocean, Mechanical and Aerospace -scientists and engineers- (ISOMAse)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.36842/jomase.v16i1.460

Abstract

The airflow through the main rotor blade system of a helicopter is still not exceedingly well understood owing to its obscurity in aerodynamics. It is prognosticated that helicopter wakes can be significantly greater than those formed by a fixed wing aircraft of the same weight. Nuisance incidents such as brownout & noises are engendered from rotor wake. Study through flow visualization plays a key role in understanding the airflow distinctiveness and vortex interaction of a helicopter rotor blade. Inspecting and scrutinizing the effects of wake vortices during operation is a great challenge and imperative in designing effective rotor system. This study aimed at finding a suitable method to visualize the main rotor airflow pattern of a remote controlled subscale helicopter and seek for the vortex flow at the blade tip. The experimental qualitative data is correlated with quantitative data to perform meticulous study on the airflow behaviour & characteristics along with its distinctiveness generated by the main rotor in various flight conditions. Simulation is also performed in similar conditions to bequeath with comparability between the flow visualization results. Several dissimilar flow patterns were identified throughout the blade span. At the centre of the main rotor hub, the presence of turbulent flow was perceived. This is because of the low energy of air pooled in this region. Conversely, an apparent straight streamline pattern in the middle portion of the rotor blade was noticed as the air in this section encompassed high kinetic energy.
Reviewed on Combustion Modelling of Marine Spark-Ignition Engines Nekooei, Mohammad Javad; Koto, Jaswar; Priyanto, A.; Dehghani, Zahra
Journal of Ocean, Mechanical and Aerospace -science and engineering- Vol 17 No 1 (2015): Journal of Ocean, Mechanical and Aerospace -science and engineering- (JOMAse)
Publisher : International Society of Ocean, Mechanical and Aerospace -scientists and engineers- (ISOMAse)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.36842/jomase.v17i1.454

Abstract

This research reviewed combustion modelling of marine sparkignition engine using mass fraction burned based on Wiebe function approach. In the paper, firstly, the cylindrical pressure is discussed and correlated function of engine operation condition. The cylinder pressure signal was constructed as a function of crank angle over an engine operational map. The parameters of the cylindrical pressure model were calibrated with s-curve matching techniques. The objectives of the research was to construct a combustion model on the cylindrical pressure suitable for control oriented model.
Integrated Port Traffic Management using Automatic Identification System and Radar Amran, Nur Aireen; Koto, Jaswar
Journal of Ocean, Mechanical and Aerospace -science and engineering- Vol 28 No 1 (2016): Journal of Ocean, Mechanical and Aerospace -science and engineering- (JOMAse)
Publisher : International Society of Ocean, Mechanical and Aerospace -scientists and engineers- (ISOMAse)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.36842/jomase.v28i1.423

Abstract

In Vessel Traffic System (VTS), AIS can detect a larger number of targets without considering the shadow effect and can provide more voyage information for port center. For radar system can detect target actively even buoys or rock no matter ship size or fitted equipment. But even radar can detect all targets, it is cannot give full information as AIS. AIS can give full information such as types of ship, size, name, MMSI number and etc. AIS and radar system is very important in the VTS to control ship in and out at the port area. They have to use two different computers, which is one computer for AIS and another computer is for radar systems. By integrating AIS and radar, the officer can control port with more accurate and systematic. This paper will focus on integration of AIS and Radar for managing the movement of vessels in port for safety purpose by taking Port TanjungPelepas (PTP) as a case study.
Development of Automatic Identification System in Straitof Batam-Singapore Koto, Jaswar; Amran, Nur Aireen
Journal of Ocean, Mechanical and Aerospace -science and engineering- Vol 29 No 1 (2016): Journal of Ocean, Mechanical and Aerospace -science and engineering- (JOMAse)
Publisher : International Society of Ocean, Mechanical and Aerospace -scientists and engineers- (ISOMAse)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.36842/jomase.v29i1.419

Abstract

In Vessel Traffic System (VTS), AIS can detect a larger number of targets without considering the shadow effect and can provide more voyage information for port center.AIS can give full information such as types of ship, size, name, MMSI number and etc. AIS system is very important in the VTS to control ship in and out at the port area. This paper discussed on development of AIS system. The system was applied for safety purpose by taking ship tracking in Strait of Batam-Singapore.
2 MW Closed Cycle SWOTEC in Mentawai, Sumatera Barat, Indonesia Koto, Jaswar
Journal of Ocean, Mechanical and Aerospace -science and engineering- Vol 38 No 1 (2016): Journal of Ocean, Mechanical and Aerospace -science and engineering- (JOMAse)
Publisher : International Society of Ocean, Mechanical and Aerospace -scientists and engineers- (ISOMAse)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.36842/jomase.v38i1.395

Abstract

Solar, Wind and Ocean Thermal Energy Conversion (SWOTEC) is a clean marine renewable energy using temperature difference between the sea surface and the deep ocean to rotate a generator to produce electrical energy. Indonesia is an equatorial country located at latitudes less than 20 degrees covered by 77 % ocean, thousand islands, strain and many difference of topography, SWOTEC is very compatible build in Indonesian. This paper discussed on performance of 2MW closed cycle of SWOTEC in Siberut Island, Sumatera Barat-Indonesia. Siberut Island has a hot and humid tropical rainforest climate, with an annual rainfall of 4,000 mm with temperatures range 22 - 31 0C and humidity averages 81-85%. The study founded that the Siberut island has potential SWOTEC due to the gradient temperature more than 20 0C. The electricity and fresh water generated by the SWOTEC are more promising to be applied in the island.
Application of Hybrid Fuzzy Logic Controller for Controlling AFR Engine Nekooei, Mohammad Javad; Koto, Jaswar
Journal of Ocean, Mechanical and Aerospace -science and engineering- Vol 41 No 1 (2017): Journal of Ocean, Mechanical and Aerospace -science and engineering- (JOMAse)
Publisher : International Society of Ocean, Mechanical and Aerospace -scientists and engineers- (ISOMAse)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.36842/jomase.v41i1.385

Abstract

The Kyoto Protocol (1997) has been a turning point for future economic and environmental policies for both industrialized and developing countries. The vehicle engine manufacturers are continuously working towards reducing fuel consumption and emissions while maintaining optimum performance by keeping the Air to fuel ratio (AFR) as close to the stoichiometric value of 14.7. In the present paper, new simulation model using Matlab Simulink for a SI (Spark-Ignition) engine has been developed that included all engine dynamic models such as dynamic model of the throttle body, a lambda dynamic model, a model of the intake manifold dynamic, and models of engine torque and fuel injection dynamic. Then, to control the AFR in SI engines, new controllers were proposed to maximize fuel economy and minimize exhaust emissions. A hybrid fuzzy logic controller (HFLC) was created by combining a PID control and fuzzy control. However, this model was validated using the results from engine for various constant load operation tests such as 40 Nm, 50 Nm and 60 Nm but this paper only presented operation at 60 Nm. The simulation results founded that the maximum and minimum AFR for convectional look-up and HFLC methods were (16.80, 12.4) and (15.02, 14.4) respectively. Simulation results from HFLC were lower than other methods such as Sliding Mode Control (SMC), Neural Network (NN), Proportional–Integral controller (PI) and Model-based Predictive Control (MPC) extracted from publishing data.
Implementation of PSAK 64 in Indonesian Oil and Gas Companies under Production Sharing Contracts Renaldo, Nicholas; Junaedi, Achmad Tavip; Suhardjo, Suhardjo; Tanjung, Amries Rusli; Jahrizal, Jahrizal; Dalil, M; Arief, Dodi Sofyan; Koto, Jaswar; Musa, Sulaiman; Veronica, Kristy
International Conference on Business Management and Accounting Vol 3 No 2 (2025): Proceeding of International Conference on Business Management and Accounting (May
Publisher : Institut Bisnis dan Teknologi Pelita Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35145/icobima.v3i2.5115

Abstract

This study seeks to identify best practices, uncover implementation gaps, and provide recommendations to improve the quality and comparability of financial reporting in the sector. This study employs a qualitative case study approach to gain an in-depth understanding of the implementation of PSAK 64 in Indonesian oil and gas companies operating under the Production Sharing Contract (PSC) model. The sample is selected using purposive sampling, focusing on companies that: Operate in the upstream oil and gas sector in Indonesia, are governed by the PSC model, and have published financial reports in accordance with PSAK 64. The study findings reveal that while companies generally comply with the basic requirements of PSAK 64, there is considerable variation in the interpretation and application of specific provisions, particularly those related to the recognition, measurement, and disclosure of exploration and evaluation (E&E) assets. This study contributes to the accounting literature by highlighting how a single standard (PSAK 64) can be applied differently based on the contractual and regulatory environment.
Empowering Farmers Through a Practical and Energy-Efficient Goat Feed Chopping Machine Dalil, M; Arief, Dodi Sofyan; Jahrizal, Jahrizal; Junaedi, Achmad Tavip; Susanti, Wilda; Tendra, Gusrio; Renaldo, Nicholas; Koto, Jaswar; Musa, Sulaiman; Wahid, Nabila; Cecilia, Cecilia
International Conference on Business Management and Accounting Vol 2 No 2 (2024): Proceeding of International Conference on Business Management and Accounting (May
Publisher : Institut Bisnis dan Teknologi Pelita Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35145/icobima.v2i2.5075

Abstract

This initiative is part of a broader commitment to support rural agricultural development through technological innovation and knowledge transfer. Through workshops, demonstrations, and direct community involvement, this program will not only provide access to the feed chopper but also equip farmers with the skills and understanding needed to adopt and sustain its use. This community service project was designed using a participatory and problem-solving approach, integrating technical innovation with local knowledge to empower goat farmers. This community service initiative successfully introduced a practical and energy-efficient goat feed chopping machine to a rural farming community. The machine effectively addressed key challenges in manual feed preparation, including time consumption, labor intensity, and inconsistency in feed size. This initiative demonstrates that small-scale engineering solutions, when aligned with local needs and capacities, can significantly advance rural development and agricultural sustainability.