• Title/Summary/Keyword: Open sea

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A Relationship between Oceanic Conditions and Meteorological Factors in the Western Sea of Korea in Winter (동계 서해의 해황과 기상인자와의 관계)

  • Go Woo-Jin;Kim Sang-Woo;Kim Dong-Sun
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.12 no.1 s.24
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    • pp.23-32
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    • 2006
  • This study was conducted to find out the effects of meterological factors on oceanic conditions when cold and dry continental air mass passes through the western sea of Korea The change of ocean conditions during the winter season were more obvious in coastal area than open sea And sea surface temperature (SST) during February is lower by $3^{\circ}C$ than December but in coastal area SST dropped by $3^{\circ}C$. As for the salinity, there was not much difference between areas except southern area of Mokpo. In the coastal regions, air temperature(AT) and SST showed a positive correlation; as the air temperature goes up with the increase of SST and when the former goes down the latter decrease. SST of open sea seems to be changed by latent (Qe) and sensible heat (Qs), when the open sea lose its heat by Qe and Qs then SST goes down And when they get the heat then the SST goes up. 1here was a positive correlation between the AT of the coastal region and sea surface salinity (SSS), when the AT goes up then SSS increase and when the former goes down the latter decrease. Precipitation during the summer seasons (June$\sim$September) appeared to the more closely related with salinity of February of the following year than those of October and December.

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The Radiation Evaluation for Development of Solar System by Using Solar on the Sea (해상용 태양열 시스템 개발을 위한 일사량 평가)

  • 강일권
    • Journal of Ocean Engineering and Technology
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    • v.14 no.2
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    • pp.13-18
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    • 2000
  • Recently due to the environmental pollution and the requirement for the substitute energy the interest for development of the solar energy system has been highly escalated It has been approved that the solar energy is a very useful on e because of purity and low cost. Some studies about the evaluation of solar radiation on the land has been carried out but few studies on the sea. This paper deals with a study on the evaluation of solar radiation on the sea. The experiments were carried out on the training vessel on the adjacent water of Korea Japan and China for twenty days. The distributions of solar radiation from the sea were changed into nonlinear in from according to the temperature. The solar radiation on the sea has a great influence on the velocity of wind as well as the temperature The distribuition of solar radiation has higher values on the track of the coastal sea than the open sea at same conditions.

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Comparison of Topex/Poseidon sea surface heights and Tide Gauge sea levels in the South Indian Ocean

  • Yoon, Hong-Joo
    • Proceedings of the KSRS Conference
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    • 1998.09a
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    • pp.70-75
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    • 1998
  • The comparison of Topex/Poseidon sea surface heights and Tide Gauge sea levels was studied in the South Indian Ocean after Topex/Poseidon mission of about 3 years (11- 121 cycles) from January 1993 through December 1995. The user's handbook (AVISO) for sea surface height data process was used in this study Topex/Poseidon sea suface heights ($\zeta$$^{T/P}$), satellite data at the point which is very closed to Tide Gauge station, were chosen in the same latitude of Tide Gauge station. These data were re-sampled by a linear interpolation with the interval of about 10 days, and were filtered by the gaussian filter with a 60 day-window. Tide Gauge sea levels ($\zeta$$^{Argos}$, $\zeta$$^{In-situ}$ and $\zeta$$^{Model}$), were also treated with the same method as satellite data. The main conclusions obtained from the root-mean-square and correlation coefficient were as follows: 1) to Produce Tide Gauge sea levels from bottom pressure, in-situ data of METEO-FRANCE showed very good values against to the model data of ECMWF and 2) to compare Topex/Poseidon sea surface heights of Tide Gauge sea levels, the results of the open sea areas were better than those of the coast and island areas.

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Three-Dimensional Finite Element Modeling for the Yellow Sea - Initial approach -

  • Suh, Seung-Won;M.G.G. Foreman
    • Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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    • 1996.10a
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    • pp.14-14
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    • 1996
  • In order to understand the tidal hydrodynamics of the Yellow Sea and Parts of the East China Sea, we have developed a three-dimensional, fine resolution, nonlinear, harmonic finite element model. Major four tidal constituents, M$_2$, S$_2$, K$_1$ and O$_1$ are used as forcing along the open boundary. Due to the shallowness of the region, tidal results are strongly affected by the bottom roughness coefficients, especially for the quadratic form. (omitted)

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DSP Implementation and Open Sea Test of Underwater Image Transmission System Using QPSK Scheme (QPSK 방식을 이용한 수중영상 정보전송 시스템의 DSP구현 및 실해역 실험 연구)

  • 박종원;고학림;이덕환;최영철;김시문;김승근;임용곤
    • The Journal of the Acoustical Society of Korea
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    • v.23 no.2
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    • pp.117-124
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    • 2004
  • In this paper, we have been implemented the QPSK-based underwater transmission systems using DSP in order to transmit the underwater image data. We have adopted a BDPA (Block Data Parallel Architecture) to control multiple DSPs used in the transmitter and receiver in order to transmit the image data in real-time. We also have developed GUI software in order to drive and to debug the implemanted system in real-time. We have executed open sea tests in order to analyze the performance of the implemented system at East Sea near Kosung in Kangwon-Do. As a result of these experiments, it has been demonstrated that 10 kbps image data can be received without errors at 30m and 80m depth points, while the distance between the transmitter and the receiver is up to 20m.

Environmental Factors and the Distribution of Eggs and Larvae of the Anchovy (Engraulis japonica) in the Coastal Waters of Jeju Island (제주도 주변해역의 해양환경요인과 멸치 난자치어 분포)

  • Ko, Joon-Chul;Yoo, Joon-Taek;Rho, Hong-Kil
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.40 no.6
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    • pp.394-410
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    • 2007
  • Anchovy spawn from the end of May to mid-October, when the water temperature is $14.8-27.2\;^{\circ}C$ and the salinity is 26.0-33.6 psu. The main spawning season is between July to August, when the water temperature is $21.7-27.2\;^{\circ}C$ and the salinity is between 26.0-32.2 psu. The main spawning grounds of anchovy are coastal areas shallower than 50 m around the islands located in the Jeju Strait. Anchovy larvae are distributed near the fronts between Chuja-do, Jangsu-do, Yeoseo-do, and the open sea rather than in the spawning grounds. Anchovy eggs and larvae density increased in accordance with the high level of $Chlorophyll-{\alpha}$ during the summer season (July-August). In terms of the suspended sediment (SS) levels along the northern coast of the Jeju Strait, high densities of anchovy eggs (12.0-18.0 mg/L) were observed, mainly in the area affected by the coastal waters of the southern sea with high SS levels, while larvae (10.0-19.0 mg/L) tended to be distributed over a wide area with high SS levels, including the open sea. In terms of the dissolved oxygen (DO) content, eggs (5.4-6.8 mg/L) were observed in coastal areas with a high DO content, while larvae (4.2-6.4 mg/L) were distributed widely in areas with a relatively low DO content, from the southern coast to the open sea.

Improvement Alternative of Korean Environmental Assessment through the EA of the European Union (유럽연합의 EA에 비춰본 한국의 환경평가제도 개선 방안)

  • Kim, Im-Soon;Han, Sang-Wook;Park, Joo-Hyun
    • Journal of Environmental Impact Assessment
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    • v.15 no.2
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    • pp.139-155
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    • 2006
  • The introduction of Strategic Environmental Assessment (SEA) has strengthened and extended the value of Environmental Impact Assessment (EIA) as a fundamental tool for sustainable development. In particular, SEA helps to overcome the limitation of project EIA as a stand alone approach that is applied relatively late in the decision making cycle. SEA is applied to proposals of policy, plan, and/or programme when major alternatives are open. In Korea, similar to SEA, the Prior Environmental Review System (PERS) was introduced to overcome the limitations of the EIA, by checking the environmental impacts on major policy and administrative actions in the early stage of decision making process. SEA appears in various national, regional and international laws. SEA is addressed specifically in the UNECE SEA protocol to the Espoo Convention on Environmental Impact Assessment in a transboundary context, as well as the European Commission SEA Directive (2001/42/EC). SEA is a valuable tool for integrating sustainability decisions into country's policies, plans and programmes. This paper reviews the policy direction for implementation of the SEA and efficient Environmental Assessment (EA) through integration of the PERS and the EIA.

Study on the Korean Waters using the CAL/VAL of the OSMI Level 2 Data

  • Suh, Young-Sang;Jang, Lee-Hyun;Mitchell, B.G.;Kahru, M.;Prasad, Kota;Shin, H.Y.
    • Korean Journal of Remote Sensing
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    • v.18 no.3
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    • pp.127-139
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    • 2002
  • A comparison was made between the chlorophyll $\alpha$ and suspended solid (SS) retrievals from OSMI and SeaWiFS sensor to chlorophyll $\alpha$ and SS values determined with the standard method during the NFRDI's research cruises. The percentage of organic and inorganic materials from the SS was calculated to study the contribution of turbid water in the northern part of the East China Sea. The open sea waters in the Kuroshio regions of the East China Sea showed relatively higher concentration of volatile SS. However, towards the northwestern part of the East China Sea, the situation became much more optically different with the non-volatile SS from the Yangtze river and the sea bottom sources in the sea in winter and spring seasons. Furthermore, in order to indirectly detect low salinity water with high turbidity, which related to the Yangtze river using remote sensed data from the satellites, a comparison between the results of the band ratio(nLw 490nm/nLw 555nm) of SeaWiFS(OSMI) and the distribution of low salinity around the Jeju Island was presented.

Release of Ammonia Odor from AAFA (Ammonia Adsorbed Fly Ash) by Installation of NOx Reduction System

  • Kim, Jae-kwan;Park, Seok-un;Lee, Hyun-dong;Chi, Jun-wha
    • KEPCO Journal on Electric Power and Energy
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    • v.2 no.3
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    • pp.437-445
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    • 2016
  • This paper discussed the effect of ammonia concentration adsorbed on fly ash for the ammonia emission as AAFA (Ammonia Adsorbed Fly Ash) produced from coal fired plants due to operation of NOx reduction technologies was landfilled with distilled or sea water at closed and open systems, respectively. Ammonia bisulfate and sulfates adsorbed on fly ash is highly water soluble. The pH of ammonium bisulfate and sulfate solution had significant effect on ammonia odor emission. The effect of temperature on ammonia odor emission from mixture was less than pH, the rate of ammonia emission increased with increased temperature when the pH conditions were kept at constant. Since AAFA increases the pH of solution substantially, $NH_3$ in the ash can release the ammonia order unless it is present at low concentration. $NH_4{^+}$ ion is unstable in fly ash and water mixtures of high pH at open system, which is changed to nitrite or nitrate and then released as ammonia gas. The proper conditions for < 20 ppm of ammonia concentration released from the AAFAs landfilled in ash pond were explored using an open system with sea water. It was therefore proposed that optimal operation to collect AAFA of less than 168 ppm ammonia at the electrostatic precipitator were controlled to ammonia slip with less than 5 ppm at SCR/SNCR installations, and, ammonia odor released from mixture of fly ash of 168 ppm ammonia with sea water under open system has about 20 ppm.

A Study on A Proper Application for The Navigational Rules in The Public Order in Open Port Act (개항질서법상 항법적용)

  • JI, Sang-Won
    • Journal of Navigation and Port Research
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    • v.28 no.5
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    • pp.359-364
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    • 2004
  • When sea going vessel approaches her destination port, marine traffic density is increased, especially, the marine traffic is concentrated in the entrance channel and the fairway in the inner harbour is more narrow. Therefore, special navigational rules for preventing collision at sea is needed in the inner harbour. Hence there are the rules in The Public Order in Open Port Act in Korea But, in the case of conflict of navigational rule concerned, it is possible to be raised a question that which rule shall be applied preferentially. Also, it is necessary to understand the exact meaning of the navigational rules in The Public Order in Open Port Act. Because the misunderstanding of the rule is caused the collision Therefore, this paper aims to discuss the exact meaning of the navigational rule concerned in the view of legal basis and suggest the principles for a proper application of it.