• Current Photovoltaic Research
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• v.1 no.2
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• pp.122-125
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• 2013

The Floating Photovoltaic System was installed on the surface of water. There were some researches in this subject. But there was not many studies with experiment on a high waterproof Floating Photovoltaic modules. The aim of this study was to analyze the performance of the Floating Photovoltaic System. For this experiment, a high waterproof Floating Photovoltaic modules were designed and applied to the module capacity of 10 kW Tracking-Type structure. The experiment results indicated the performance of the daily production is 51.6 kW; the production capacity of Floating Photovoltaic System is expected to be 23% higher than that of the ground-mounted photovoltaic system.

• Journal of Ocean Engineering and Technology
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• v.26 no.1
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• pp.78-83
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• 2012

The abundant nutrients contained in deep seawater are delivered by natural upwellings from the deep sea to the surface sea. However, the natural upwelling phenomenon is limited to specific areas of the sea; in other areas, the thermocline separates the surface sea from the lower layer. Thus, the surface layer is often deficient in nutritive salts, causing the deterioration of its primary productivity and ultimately leading to an imbalance in the marine ecosystem. Without a consistent supply of nitrogenous nutritive salts, they are absorbed by phytoplankton, resulting in a considerable problem in primary productivity. To solve this issue, a floating type of artificial upwelling system is suggested to artificially pump up, distribute, and diffuse deep seawater containing rich nutritive salts. The key technologies for developing such a floating artificial upwelling system are a floating offshore structure with a large diameter riser, self-supplying energy system, density current generating system, method for estimating the emission and absorption of CO2, and way to evaluate the primary production variation. Strengthening the primary production of the sea by supplying deep seawater to the sea surface will result in a sea environment with abundant fishery resources.

• Journal of Advanced Marine Engineering and Technology
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• v.39 no.3
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• pp.342-347
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• 2015

Floating LNG is a new concept which is used as LNG regasification/receiving facility and for LNG production/export facility. LNG Floating Production Storage and Offloading(FPSO) concept will put vitality into marginal gas fields which were delayed because of excessive investment cost in the world. LNG Floating Storage Regasification Unit(FSRU) also provides commercially competitive and effective solutions to the areas where onshore infrastructure is not well established. LNG cargo containment system is one of the key functions for FLNG to store produced LNG on a floating structure. This paper presents a new technology related to a LNG containment system; a combined cargo containment system utilizing the advantages of iIndependent tank type and membrane system. Technical advantages have been validated through research work.

• Ocean Systems Engineering
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• v.12 no.1
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• pp.39-61
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• 2022

Renewable energy such as wave energy has gained popularity as a means of reducing greenhouse gases. However, the high cost and lack of available sea space in some countries have hindered the deployment of wave energy converters (WEC) as alternative means of sustainable energy production. By combining WECs with infrastructures such as floating breakwaters or piers, the idea of electricity generated from WECs will be more appealing. This paper considers the integration of vertical raft-type WEC (commonly known as the vertical flap WEC) with floating breakwater as means to generate electricity and attenuate wave force in the tropical sea. An array of 25 WECs attached to a floating breakwater is considered where their performance and effect on the wave climate are presented. The effects of varying dimensions of the WEC and mooring system of the floating breakwater have on the energy generation are investigated. The integrated WECs and floating breakwater is subjected to both the regular and irregular waves in the tropical sea to assess the performance of the system. The result shows that the integrated vertical flap-floating breakwater system can generate a substantial amount of wave energy and at the same time attenuate the wave force effectively for the tropical sea when optimal dimensions of the WECs are used.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.46 no.1
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• pp.20-31
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• 2010

In this research, the submersible fish cage was designed to avoid structural and biological damage during harsh sea conditions. The submersible cage system consists of netting, mooring ropes, a floating collar, floats, sinkers and anchors. Whole elements of the cage were modeled on the mass-spring model. The computer simulations were carried out to investigate the dynamic behavior of the cage and to calculate mooring line tension subjected to tidal currents and waves. As expected, the tension values in the mooring line of the submerged position are 36% less compared to that of the surface cage under the same loading conditions. As the wave was used in combination with the current velocity of 1m/s, the average tensile load for the submerged cage showed 85% of the value for the floating cage. The simulation results provide an improved understanding of the behaviors of the structure and valuable information on the optimized design of the cage system exposed to open ocean environmental factors.

• International Journal of Ocean Engineering and Technology Speciallssue:Selected Papers
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• v.3 no.1
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• pp.1-7
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• 2000

A new alternative for large deepwater field development is described. This "Oil Box" (aka "Box Spar") is a multifunction vessel capable of floating drilling, production, storage and offloading (FDPSO). It is distinguished from other Floating Production, Storage and Offloading (FPSO) vessels by its unique hull form and oil storage system. It's main advantages are flexibility derived from the floatover deck option, use of proven top tensioned riser technology, and motion characteristics which make it operable in a wide range of environmental conditions.

• Journal of the Korean Society of Tobacco Science
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• v.19 no.2
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• pp.102-106
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• 1997

The inluence of styrofoam-panel thickness of floating frame on the seedling growth of flue-cured tobacco(Nicotiana tabacum L.) in the newly developed direct-seed float system was investigated . Floating frame used instead of styrofoam-tray consisted of styrofoam-panel (106×108cm) for floating, eight holes(1.Sx2S.0 cm) to uniform the water, and nutrition supply far seedling and water and nutrition absorption cloth placed on the styrofoam-panel. Each floating-frame may lay eight plastic-trays on it. Eight grades of styrofoam-panel thickness from 26 mm to 46mm and two kinds of media were used in the greenhouse system. Dry cells were found from the styrofoam-panel thickness of 43mm in carbonized chaff, compost and original soil rate of L3-3(v/v) media, and of 37mm in peat and perlite rate of 8-2(v/v) media. The thinner styrofoam-panel produced more tender and succulent seedling with the more trunk and the less root weight. When considering the appearance of dry cell, seedling growth, producing healthy tobacco seedlings, and utilization of styrofoam-panel for two kinds of medias the ideal styrofoam-panel thickness were suggested to be around 34mm for flue-cured tobacco reeling production in the newly developed direct-seeding float system. Key words : tobacco seedlings, float system, medium, styrofoam pannel, dry cell.

• International Journal of Naval Architecture and Ocean Engineering
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• v.6 no.2
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• pp.307-322
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• 2014

With the rate of worldwide LNG demand expected to grow faster than that of gas demand, most major oil companies are currently investing their resources to develop floating LNG-FLNG (i.e. LNG FSRU and LNG FPSO). The global Floating LNG (FLNG) market trend will be reviewed based on demand and supply chain relationships. Typical technical issues associated with FLNG design are categorized in terms of global performance evaluation. Although many proven technologies developed through LNG carrier and oil FPSO projects are available for FLNG design, we are still faced with several technical challenges to clear for successful FLNG projects. In this study, some of the challenges encountered during development of the floating LNG facility (i.e. LNG FPSO and FSRU) will be reviewed together with their investigated solution. At the same time, research of new LNG-related technologies such as combined containment system will be presented.

• Special Issue of the Society of Naval Architects of Korea
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• 2009.09a
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• pp.97-106
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• 2009

Many production methods are tried to enhance the productivity efficiency. Parallel connected floating cranes are one of the examples to lift mega-blocks quickly and efficiently. However, a general operation manual to operate parallel connected floating cranes and a method to consider risks during lifting operation are not confirmed. And if each floating crane is operated by itself, it is very hard to cooperate. Therefore, Synchronized operation system is installed to control parallel connected floating cranes simultaneously and to be informed of each floating cranes data. And weighting factor is calculated by considering all hazards during the operation and the general operation manual is confirmed based on the factor. This paper introduces the procedure for lifting operations by parallel Connected Floating Cranes using synchronized operation system, and its applications to lifting operation of a heavy cargo such as barge lifting test, floating dock installation and 900 ton goliath crane replacement operation, etc.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2000.11a
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• pp.307-310
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• 2000

Recently, the demand for the Floating, Production Storage, and Offloading facility(FPSO) which has some economic and technical advantages, has increased in offshore oil production areas. The basic characteristics of a 343,000 DWT class FPSO which is being built in Hyundai Heavy Industries and shall be installed in offshore Angola, is almost same as that of oil carriers. However, she do not have self-propulsion system, but has additional facilities for oil production and positioning system. Main noise source contributing to the cabin noise of the accommodation, are classified into the machine in the engine room and the deckhouse, HVAC system, and the topside equipments. In general, the noise regulation for the offshore structure is much severer than that of the common commercial ships and the maximum acceptable sound pressure level of cabins is specified in 45dB(A). This paper describes the procedure of noise analysis along with its results. Noise analysis has been carried out for the case of emergency diesel generator running condition and the case of normal production condition and the results has been compared with the measurement results of the first case. Based on the results, proper countermeasures to reduce excessive noise level has been applied considering the characteristics of sources and receiver spaces and can be satisfied the specifications at all spaces.