• 한국해양공학회지
• /
• 제17권2호
• /
• pp.72-76
• /
• 2003

This paper presents the design concept and operation results of float-off for FSO (340,000 DWT Class, ELF AMENAM KPONO Project) built on the ground, without dry dock facilities. It was the first attempt to build FSO, completely, on the ground and launch it using DBU (Double Barge Unit, which was connected by rigid frame structure.) The major characteristics of FSO, which are similar to general VLCC type hull, including topside structure, weigh 51,000 metric ton. In order to have sufficient stability during the deck immersion of DBU, while passing through a minimum water plane area zone, proper trim control was completed with LMC (Load Master Computer). The major features of the monitoring system include calculation for transverse bending moment, shear force, local strength check of each connector, based on component stress, and deformation check during the load-out and float-off. Another major concern during the operation was to avoid damages at the bottom and sides of FSO, due to motion & movement after free-floating; therefore, adequate clearances between DBU and FSO were to be provided, and guide posts were installed to prevent side damage of the DBU casings. This paper also presents various measures that indecate the connector bending moment, damage stability analysis, and mooring of DBU during float off.

• 한국해양공학회:학술대회논문집
• /
• 한국해양공학회 2002년도 추계학술대회 논문집
• /
• pp.206-211
• /
• 2002

FPSO(FSO)같은 대형 구조물을 육상에서 건조하여 LOAD-OUT 과 FLOAT-OFF 를 수행하기 위해 한 척의 반 잠수바지로는 불가능하였다. 그래서 두 척의 반 잠수 식 바지를 HINGED TYPE 이 아닌 FIXED TYEP 으로 연결하였고 이에 따라 FLOAT OFF 시에 고려하여야 할 사항 중에서 횡강도 및 바지가 잠수 할 시점의 STABILITY 가 중요시되었다. 또한 FSO 가 잠수바지로부터 떨어져 나올 시점에서, STABILITY CASING 과 FSO 와의 충돌가능성도 고려하여야 할 사항이다. 이 논문에서는 안정성 측면에서의 반 잠수식 바지의 BALLASTING과 충돌방지 차원에서 전체적인 OPERATION에 대하여 언급하였다.

• 한국해양공학회:학술대회논문집
• /
• 한국해양공학회 2002년도 추계학술대회 논문집
• /
• pp.51-55
• /
• 2002

End of July. 2002 Hyundai Heavy Industries Co. Ltd. Offshore Division is successfully completed Load-out & Float-off work of "AMENAM KPONO/FSO Project" similar to 300K VLCC size. The AMENAM FSO hull and topside module built at the HHI Offshore yard using "On-Ground Building Method" developed by HHI. Various methodologies/techniques like Flexi-built FPSO Hull. Topside module erection method. Load-out Float-off methodology etc. are combined to develop a successful on-ground building method. In this paper, we described the "Hull Structural Strength Analysis Methodology" using 3-D Finite Element Analysis and results. This analysis is performed to verily the structural integrity or the AMENAM FSO hull during the main load-out on two semi-submersible barges combined together.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 1991년도 한국자동제어학술회의논문집(국제학술편); KOEX, Seoul; 22-24 Oct. 1991
• /
• pp.1899-1903
• /
• 1991

This paper presents a water level control method using Z-80 microcomputer. The process considered in this paper is one tank system which is described by an unknown nonlinear differential equation. The water level is measured by the end of bar installed at a float passing through 8 pair of photointerrupters located at equal distance. Therefore, the input data to 8255 which is interface between Z-80 and photointerrupters is discrete value, namely, value under 1. values from 1 to 8, and value upper 8. The water is pumped into the tank from a reservoir by switching on a relay connected to a moter and pump driving system. The pumping is stopped by switching off the relay. Experimental studies for two types of controllers are performed in order to investigate the control performance of water level of the water pumping system.

• 수산해양기술연구
• /
• 제22권4호
• /
• pp.32-40
• /
• 1986

A model experiment of purse seine by the circulating water tank was carried out on the changes of net shape and the tension of purseline under operation in two layer current. In the circular tank, the two layer current was made by cutting off the current of upper layer and producing the bottom current by the equipment shown in Fig. 1. The model experiment of purse sein was made on a reduced scale 1 :400, and the experiment was carried out according to the Tauti's model law. When the bottom current of O. 5 knot flows to lower part of three-eighths of net, following results are derived. The depth of sinkerline reached only about 80% of that of no current set. The horizontal shift of sinker line caused by the bottom current is maximized in tight set. The enclosed area by the floatIine immediately after the completion of set net is 61. 5% in tight set, 50. 0 % in loose set and 54. 1 % in lateral set of those in the case of no current. In the first half period of pursing, the tension of the purseline is enhenced by the bottom current and the pattern of increasing is irregular in the tension curves.

• 한국펄프종이공학회:학술대회논문집
• /
• 한국펄프종이공학회 2006년도 PAN PACIFIC CONFERENCE vol.1
• /
• pp.129-136
• /
• 2006

Although cleaner and cheaper deinking of ONP could be performed at the neutral or low alkaline condition excessive loss from froth-flotation is unavoidable and so reduction of alkali or caustic soda dosage sacrifices recycling yield. Now the new trade-off regarding alkali dosage versus flotation yield is urgently required in order to set the optimized neutral or low alkaline deinking process of ONP. Lipase from Thermomyces Lanuginosus has an effect on desizing and deacetylation reaction and it could be applied to the stock of pre flotation secondary stage in order to reduce the flotation reject without the sacrifice of optical properties of flotation accepts. Instead of inorganic base, lipase could be applied as a biochemical catalyst for the selective modification of valuable hydrophobic particles in deinking stock, for example cellulose fines and inorganic fillers covered by hydrophobic additives or contaminants. When the enzymatic hydrolysis of ester bond could be made on the surface of hydrophobic particulates, unwanted float of fine particles could be prevented. Now the enhancement of flotation selectivity or the modification of the hydrophobicity of deinking stock is expected to be promoted by the enzymatic pre treatment. And the reduction of recycling cost with the saves of raw material, recovered paper would be possible as a result.

• 수산해양기술연구
• /
• 제46권2호
• /
• pp.148-156
• /
• 2010

This study was conducted to collect the information on the behavioral characteristics and the habitat environment of mandarin fish (Siniperca schezeri) and catfish (Parasilurus asitus) with acoustic telemetry method in Chungju Lake, Korea. Mandarin fish tended to stay within 1km from the release points in downstream, and had a strong diurnal behavior. They approached to the lakefront at night. They also preferred to stay at deep water off the lakefront. The average swimming speed was faster at night (0.4BL/s) than during a day (0.2BL/s). They swam the shallow water area at night. Catfish frequently moved between upstream and downstream. Catfish tended to act during a day. The average swimming speed was faster during a day (0.3BL/s) than at night (0.2 BL/s). The average swimming depth was 14.3m, and they tended to float about 4m during a day.

• Ocean Science Journal
• /
• 제40권1호
• /
• pp.25-44
• /
• 2005

Long-term, continuous, and real-time ocean monitoring has been undertaken in order to evaluate various oceanographic phenomena and processes in the East/Japan Sea. Recent technical advances combined with our concerted efforts have allowed us to establish a real-time monitoring system and to accumulate considerable knowledge on what has been taking place in water properties, current systems, and circulation in the East Sea. We have obtained information on volume transport across the Korea Strait through cable voltage measurements and continuous temperature and salinity profile data from ARGO floats placed throughout entire East Sea since 1997. These ARGO float data have been utilized to estimate deep current, inertial kinetic energy, and changes in water mass, especially in the northern East Sea. We have also developed the East Sea Real-time Ocean Buoy (ESROB) in coastal regions and made continual improvements till it has evolved into the most up-to-date and effective monitoring system as a result of remarkable technical progress in data communication systems. Atmospheric and oceanic measurements by ESROB have contributed to the recognition of coastal wind variability, current fluctuations, and internal waves near and off the eastern coast of Korea. Long-tenn current meter moorings have been in operation since 1996 between Ulleungdo and Dokdo to monitor the interbasin deep water exchanges between the Japanese and Ulleung Basins. In addition, remotely sensed satellite data could facilitate the investigation of atmospheric and oceanic surface conditions such as sea surface temperature (SST), sea surface height, near-surface winds, oceanic color, surface roughness, and so on. These satellite data revealed surface frontal structures with a fairly good spatial resolution, seasonal cycle of SST, atmospheric wind forcing, geostrophic current anomalies, and biogeochemical processes associated with physical forcing and processes. Since the East Sea has been recognized as a natural laboratory for global oceanic changes and a clue to abrupt climate change, we aim at constructing a 4-D continuous real-time monitoring system, over a decade at least, using the most advanced techniques to understand a variety of oceanic processes in the East Sea.

• 보존과학회지
• /
• 제25권4호
• /
• pp.347-361
• /
• 2009

포항 칠포리 지역의 암각화는 한반도에서 암각화의 도상이 가장 많고 넓게 분포하는 곳이다. 포항 칠포리와 신흥리 암각화는 석영과 장석이 반정과 기질로 산출되는 유문암질암인 암반과 전석에 방패형, 여성성기형, 윷판형 등의 그림이 새겨져있다. 암석의 표면은 황갈색을 띠며 심한 풍화에 의해 불규칙한 요철 양상을 보이고 점토광물로는 일라이트와 고령토가 산출된다. 이들 점토광물과 수용성 염성분에 의해 표면박리와 입자박락 현상이 발달되어진다. 훼손양상은 주로 표면박리, 입자박락, 파손 및 낙서 등이다. 칠포리 암각화의 1면은 강수에 의한 침식이, 2면은 표면의 마모현상이, 3면은 표면박리현상이, 그리고 4면은 토양화가 심하다. 신흥리 암각화의 1면은 강수에 의한 마식현상과 흑화현상이, 2면은 표면박리와 낙서가 심하다. 훼손요인은 지형, 식생, 풍화에 비교적 약한 암상 및 인위적 영향(음각 낙서와 산불 등)등 이다. 보존을 위해서는 약해진 표면층의 보존처리와 주변 환경의 정리 및 차수벽의 설치 등의 대책이 필요하다.