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Several advantages of multihull, such as catamaran, have been extensively discussed in the previous research. Therefore, this research focuses on developing a catamaran hull form for the fish processing vessel hull. The initial stage is determining the principal dimension and exploring the configurations of catamaran hull forms. The existing high-speed craft catamarans have been adopted to determine the parent model main dimensions using a linear regression equation model. Otherwise, the catamarans single demi-hull geometry was developed by converting and modifying the parent model hull form with enlarging the hull displacement to achieve the deadweight capacity and service speed requirements. The demi-hull spacing configuration with s/L 0.17, s/L 0.20, s/L 0.30, and s/L 0.40 on the resistance characteristics, intact stability, and sea-keeping behaviour were also explored. Furthermore, the comparisons with the previously proposed monohull were presented. Regarding the hull resistance performance, the analysis indicated that the catamaran hull form had better total resistance characteristics than the monohull on the service speed over 23 knots. In the case of intact stability, the analysis results presented that the catamaran hull form has better intact stability characteristics than the monohull. The dynamic stability of the catamarans also gave better dynamic stability at the heeling angle below 41.57°. Otherwise, the catamarans with s/L 0.17 and s/L 0.20 have lower dynamic stability than the monohull at the heeling angle larger than 41.57° and 58.03°, respectively. In the sea-keeping performance, the catamaran hull has shown an excellent rolling motion required for the offshore environment loading/unloading process. The large demi hull spacing of the catamarans hull can reduce the effect of the wave creating load on the roll motion response at the Beam Sea.

The main objective of the research was to investigate the structural response of the Glass Fiber Reinforced Plastic modular pontoon unit due to the impact load during the drop test. The impact load was defined as the drop phenomena that might be occurred while GFRP modular pontoon unit is being packaged, stacked and transported. Numerical simulation was performed using nonlinear finite element method to obtain the response characteristics. The maximum effective (Von Mises) stress of the GFRP modular pontoon unit was estimated as a design consideration for the structure strength. The external dynamics parameter which includes as the drop orientation and drop velocity which is equivalent to the drop height is being considered on the simulation analysis. According to the simulation result, it can be found that the maximum effective stress is occurred on the corner side drop position. The magnitude of maximum effective stress is larger than the yield strength of the GRFP material. Therefore the plastic deformation is observed on the corner side of the modular pontoon unit. The results of simulation analysis present that the most vulnerable drop position is the corner side position. It is recommended that the corner side of the modular pontoon unit is the important part for design improvement to increase the structure reliability during the drop phenomena.

In the shipbuilding and ship repair industry, the most common surface preparation technique used is abrasive blasting. The abrasive blasting and the other surface preparation techniques are the significant sources of shipyard waste and air pollution. The one of any kind techniques to reduce the hazardous air contaminant associated with the abrasive media is blasting room. The abrasive blasting operation is isolated by the blasting room to reduce the exposure to the shipyard environment. The portable blasting room design has been developed using the modular wall panel system. The research is focused on the strength analysis of portable modular blast room using glass reinforced plastics as the wall panels. The research method has two main steps during the strength analysis of the portable blast room. At first, the geometric form of the modular blast room was developed and defined to obtain the finite element model. Secondly, the load and boundary condition was defined, considering the wind load and the structure weight which are exerted to the blast room structure. The displacement method was adopted for the numerical analysis.

The size of net cages increases rapidly, reaching volumes above current experience. More exposed locations are used for fish production, introducing higher loads on the net cage and fish farm from strong water currents and large waves. Strength analysis can be a useful tool for development of net-cage designs to avoid escape of fish and ensure sufficient volume for good fish welfare and water quality. The main objectives of this research are to investigate the structural response of modular pontoon collar floating cage due to the current load to support the fish farming activities. Strength analysis was performed using commercial explicit finite element software to calculate the distribution of loads in the net cage due to current, weights and gravity. The net cage was modeled using truss elements that represented several parallel twines. Sub-elements allowed the trusses to buckle in compression, and only negligible compressive forces were seen in the numerical results. Resulting drag loads and cage volume were shown to be dependent on the net cage size and collar shape.

During floods disaster in the heavy populated residential area, the lack of existing life saving appliances system such as rubber boat and wooden boat were not able to evacuate the disaster victims spontaneously in mass. The condition might be explained since the rubber boat and wooden boat have limited occupant capacity. Based on the conditions, the main objectives of the research are focused on the evaluation of the application of modular floating pontoon as multipurpose floating equipment to support floods disaster evacuation process. The investigation of the modular floating pontoon performance such as hydrostatics characteristics, the equilibrium condition and the intact stability was studied using strip theory and Krylov’s method. Furthermore, the strength analysis of the modular floating pontoon structure was calculated using finite element method. The results show that the modular floating pontoon is reliable to support the evacuation process.

Composite materials have offered some improvements on the performance of hydrodynamic and structures of marine constructions. The high strength to weight and stiffness to weight ratio might be tailored through the exploitation of the fiber orientation in order to reduce the load and the stress distribution of the structure. In order to fully explore the performance of the developed glass fiber reinforce plastics (GFRP) B-series propeller for traditional purse seine boat in the North Coast of Central Java, the aim of the research is focused on the comparison of the rigid and the flexible model adopted for the simulation analysis of the propeller performance. The thrust force, the torque moment and the efficiency of the two propeller models are discussed.

Recently the diversity of fish populations in the waters Karimunjawa Island is only appreciated by those who have the ability to play diving and snorkeling. It is due to the unavailability of a vehicle that is specially made to delight in the fascination of the underwater panorama. One of the alternative solutions is using the glass bottom boat technology which is using transparent bottom that might look out the underwater scenery instead of swimming and snorkeling. The paper has focused on the study of intact stability and seakeeping characteristics of glass bottom boat trimaran in Karimunjawa Island. The intact stability characteristics will be investigated at the various load cases and weight distribution configurations which are influenced by the passenger positions and fuel tank condition. Regarding the seakeeping performance analysis, the ITTC-Bretschneider will be adopted as the wave spectrum at the wave parameters defined from the operational environment. The influence of the parameters on the stability and seakeeping of the glass bottom boat trimaran are presented and discussed.

Modular floating pontoon is a floating device commonly used as civil and marine construction. Pontoon is usually made of steel and high-density polyethylene (HDPE). Although the steel and HDPE has its own advantages and disadvantages in terms of economic, strength, and capacity. However the study of alternative raw materials for modular floating pontoon construction as multipurpose floating equipment is needed. Ferrocement which is familiar in the used for building construction material is an alternative material. Since the material is easy to find and it is such a versatile material that can be mass produced and has the mechanical strength that is simillar to steel and other materials. Following that condition the research is focused on the application of ferrocement technology for modular floating floating pontoon. The results show that the principal dimension of modular floating pontoon are length 80 cm, width 80 cm, height 75 cm, with the lightweight draft of pontoons is 30 cm. The material proportions for the modular floating pontoon are sand 48.2%, cement 34.5% and water 17.3%. Modular floating pontoon series consists of four Pontoons Square compiled with interlink (hook) so that the total of the package pontoon has a 160 cm long, 160 cm wide and 75 cm high.

Aulia Windyandari, in paper simulation model of development method for passenger savety evaluation of freefaal lifeboat explain that since the launching procedure of Freefall Lifeboat (FFL) may have an impact with the water surface, the occupant injury is possible be occured in the evacuation process of the offshore structures. The FFL shock acceleration has been conducted by the impact force when the lifeboat entry the water surface. If the shock acceleration over the human conciousness allowance, the serious injury will be happened during the FFL launching.According to the conditions, the IMO regulations have standard for the acceptance criteria of FFL shock acceleration induced by water entry impact load. The results measurement of Combined Acceleration Ratio Index (CAR) or Combined Dynamic Response Ratio Index (CDRR) should be comply with the IMO index criteria.In this paper, the methodology of FFL acceleration response prediction by the simulation model analysis will be proposed. The simulation model will be developed by using LS-Dyna code. The Simplified Arbitratry Lagrangian Eulerian Coupling will be used to define the coupling analysis between the Lifeboats (Lagrangian elements) with Water Fluids (the Eulerian Elements)Keywords: Free Fall Lifeboat, Response Acceleration, Impact Load

The freefall lifeboats have been designed to be fast and reliable evacuation system. Once the occupants have gone onboard, the lifeboat is simply sliding from a skid before the freefall. Some second after the water impact, the propulsion system can be started and the lifeboat can sail away from parent vessel. During the launching process, trajectories of freefall lifeboats can be divided into such categories, depending on the headway and advance speed after water entry and surfacing of the lifeboats. The aim of the paper is investigating the influence of the launching parameters such as, sliding distance, angle of skid and the falling height on the motion pattern of the freefall lifeboats by using Fluid Structure Interaction (FSI) analysis. The fluid structure interaction analysis is simulated using penalty coupling algorithm. The fluid is treated on a fixed mesh using a Single Material Arbitrary Lagrangian Eulerian formulation and the lifeboat structure on a rigid shell element mesh using a Lagrangian formulation. The results of the numerical simulations provide the magnitude of launching parameters for safely launching of the freefall lifeboat.