• 한국해양공학회지
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• 제22권4호
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• pp.97-105
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• 2008

This paper represents the experimental identification of a finite-dimensional dynamical plant model for the HEMIRE Remotely Operated Vehicle. The experiments were conducted during sea trials in the East Sea in October 2006 and peer testing by the South Sea Research Institute in January 2007. A least-squares method was employed to identify decoupled single degree-of-freedom plant dynamical models for the X, Y, Z and heading degree-of-freedom from experimental data. The performance of the identified plant dynamical model was evaluated by directly comparing simulations of the identified plant model to the experimentally observed motion data from the actual vehicle.

• 한국해양공학회지
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• 제24권3호
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• pp.46-51
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• 2010

This paper describes the implementation of a precise underwater navigation solution using a multi-sensor fusion technique based on USBL, DVL, and IMU measurements. To implement this precise underwater navigation solution, three strategies are chosen. The first involves heading alignment angle identification to enhance the performance of a standalone dead-reckoning algorithm. In the second, the absolute position is found quickly to prevent the accumulation of integration error. The third one is the introduction of an effective outlier rejection algorithm. The performance of the developed algorithm was verified with experimental data acquired by the deep-sea ROV, Hemire, in the East-sea during a survey of a methane gas seepage area at a 1,500 m depth.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2018년도 추계학술대회
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• pp.248-255
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• 2018

Deep-sea fishing vessel No. 501 Oryong was fully flooded through the openings and was sunk down to the bottom of sea due to the very rough sea weather on the way of evasion after fishing operation in the Bearing Sea with many crews dead and/or missed. In this study, calculation of ship stability was carried out using KST-SHIP(ship calculation system of KST), considering the effect of flow fluid and fish catch arrangement according to the progress of its sinking accident, and damage stability was analyzed. For this study, intact stability calculation of its accident ship under the full load departure condition and its calculation result were verified by comparing with each other, and intact stability according to displacement from the departure of accident ship just before the accident was calculated and analyzed. Damage stability was calculated according to the progress during sinking accident and also analyzed.

• 지구물리와물리탐사
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• 제11권4호
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• pp.286-301
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• 2008

해양과 인접한 지역에서 MT탐사 자료를 해석하는 경우, 해양은 심부 구조의 반응을 왜곡시키는 역할을 한다. 본 연구에서는 해저면 MT탐사에서 해저 지형의 영향을 제거하는 지형보정 기법을 바탕으로, 반복적으로 해양효과를 보정하는 기법을 개발하였다. 제안된 기법은 우선 관측 MT 반응에서 주변 해양의 영향을 보정하고, 그 후 해양이 없는 모델공간에서 역산을 수행한다. 주변 해양과 지하구조와의 상호결합 때문에 이 과정은 반복적으로 수행되며, 보정 결과의 변화가 미미할 때 반복과정이 종료된다. 제안된 기법의 검증을 위해 해양을 포함하는 3차원 순산 모델링을 통하여 합성 자료를 생성하였고, 1차원 및 2차원 구조에서 보정기법을 적용하였다. 대체적으로 제안된 해양효과 보정 기법은 $2{\sim}3$회의 반복단계를 거친 후 해양이 없는 경우의 지하구조를 성공적으로 복원하였다. 실제 MT 자료와 유사한 자료를 획득하기 위해 1차원 구조로 잘 알려져 있는 제주도에 대한 3차원 모델링을 수행하여 유사 현장 자료를 생성하였다. 제주도 모델의 경우, 해양효과는 약 1 Hz 이하에서 나타나기 시작하였으며 측선의 위치 때문에 해안선과 수직한 전기장 성분에서 상대 적으로 왜곡이 심하게 나타났다. 이러한 왜곡은 3회의 해양효과 보정과정을 통해 성공적으로 제거되었으며, 1차원 및 2 차원 역산은 모델링 시 가정한 제주도의 지하구조를 성공적으로 복원하였다.

• Journal of Applied Biological Chemistry
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• 제59권3호
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• pp.233-237
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• 2016

Deep sea water (DSW) contains many inorganic materials and minerals, which are extracted for use in diverse fields. However, before application, safety tests should be performed. In the present study, two DSW-extracted minerals were analyzed: calcium (Ca) and magnesium (Mg). Eye and skin irritation tests of DSW-extracted Ca and Mg were performed according to the guidelines of the Ministry of Food and Drug Safety of Korea. These two types of mineral extracts caused no symptoms of eye and skin irritation when compared to the control. These results suggest that DSW-extracted minerals caused no irritation in the eyes and on the skin, and could be safely applied to these areas.

• 한국해양공학회지
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• 제23권6호
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• pp.32-38
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• 2009

An FMEA for the waterjet-lifter of a DSNM is performed to prevent the occurrence of device failure. A waterjet-lifter raises and transports manganese nodules from the deep-sea floor up to a somewhat elevated place, from which a pin-scraper transports the lifted nodules to the inner space of the DSNM. A concept design for a device using the axiomatic design methodology is shown as the mapping between the functional domain and physical domain. The FMEA for a DSNM is introduced briefly and the rating criteria of severity, occurrence, and detection for the DSNM are defined. The FMEA of the functional requirements of a DSNM device is accomplished. Three kinds of failure modes, as well as their effects and causes, are predicted. Current design control methods for detecting potential failures, such as physical or computational experiments, design confirmation, and mathematical calculation, are described and the recommended actions for several significant causes are suggested.

• Journal of Microbiology and Biotechnology
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• 제4권1호
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• pp.36-40
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• 1994

A water sample was taken from a black smoker chimney of a deep-sea hydrothermal vent by using an unmanned submersible "Dolphin 3K". The temperature of the hydrothermal fluid from the black smoker was $276^{\circ}C$. After isolation by repeated serial dilutions, An extremely thermophilic bacterial strain was selected. The strain designated as DT1331, was an anaerobic, non-motile, coccoid shaped bacterium with about 0.5 to $1.0\;\mu\textrm{m}$ in diameter. The strain DT1331 could grow up to $93^{\circ}C$, but the optimum temperature of this strain was $80^{\circ}C$. The growth occurred in the pH range of 4.5 to 8.5 and the optimum pH was 6.0. The strain DT1331 required 1% to 5% NaCl for growth and cell lysis was observed below 1% NaCl concentration. The bacterium could grow on polypeptides such as tryptone, peptone, soytone and on proteins such as casein or gelatin. However, no growth was observed on single amino acids, sugar and organic acids. Hydrogen gas was detected slightly during growth. This bacterium obligately required elemental sulfur and hydrogen sulfide gas was produced during growth.

• Journal of Microbiology and Biotechnology
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• 제24권10호
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• pp.1337-1345
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• 2014

A novel antifungal protein produced by the fungal strain Penicillium citrinum W1, which was isolated from a Southwest Indian Ocean sediment sample, was purified and characterized. The culture supernatant of P. citrinum W1 inhibited the mycelial growth of some plant pathogenic fungi. After saturation of P. citrinum W1 culture supernatants with ammonium sulfate and ion-exchange chromatography, an antifungal protein (PcPAF) was purified. The N-terminal amino acid sequence analysis showed that PcPAF might be an unknown antifungal protein. PcPAF displayed antifungal activity against Trichoderma viride, Fusarium oxysporum, Paecilomyces variotii, and Alternaria longipes at minimum inhibitory concentrations of 1.52, 6.08, 3.04, and $6.08{\mu}g/disc$, respectively. PcPAF possessed high thermostability and had a certain extent of protease and metal ion resistance. The results suggested that PcPAF may represent a novel antifungal protein with potential application in controlling plant pathogenic fungal infection.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2006년 창립20주년기념 정기학술대회 및 국제워크샵
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• pp.319-322
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• 2006

The Deep-sea miner system is composed of body, actuators, sensors, and devices for control and monitoring. At present, we are manufacturing the miner's body included actuators and already consisted with off-the-shelf embedded controller. But sensors and those devices were just determined. To previously test performance of embedded controller which manages control and monitoring of miner system, its simulator must be developed for control and monitoring. Hardware-In-the-Loop(HIL) simulation is being increasingly used in industrial applications. This is an effective tool for the evaluation of electric system and drives. In the HIL simulator, we can test and design the control and monitoring system freely without the risk of hardware ruins and the load of expenses. Also the programming software for miner operating is verified on the HIL simulator. In this paper, we introduce the concept of HIL simulator for control and monitoring of deep-sea miner.

• Ocean and Polar Research
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• 제21권2호
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• pp.127-136
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• 1999

Radiolarian assemblages from KODOS area were analyzed in order to understand the biostratigraphy and paleoceanography of deep-sea sediment from the Northeast Equatorial Pacific. The sediment core was divided into two or three units on the basis of the chemical and physical properties. In the upper sediment, mixtures of Quaternary and Tertiary radiolarians are found indicating active reworking processes. Dissolution of radiolarians seem to increase with depth. Radiolarians are seldom in Unit III presumably due to dissolution and corrosion. The middle part of unit I appears to correspond to Collosphaera invaginata Zone (0.21 Ma). Unit II belongs to Collosphaera tuberosa Zone. Based on the absence of Stylatractus universus, we estimate its age to be younger than 0.42 Ma. Based on our analyses of radiolarians in Unit I and II, we estimated the age of unit III as Tertiary, particularly from Oligocene to Miocene. There may to be hiatuses of more than 3 My from late Miocene to Pliocene, which probably resulted from erosion and dissolution by the Antarctic Bottom Water Sedimentation rates during Quaternary range from 0.15 to 0.50 mm/ky with significant variabilities among stations. Radiolarians in the study area were mostly warm-water species.