• Title/Summary/Keyword: warm vertical

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Characteristics of the Oceanographic Environment in the Aleutian Basin of the Bering Sea during Spring (춘계 베링해 알류산 해분의 해양환경 특성)

  • Choi, Seok-Gwan;Oh, Taeg Yun
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.46 no.2
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    • pp.201-215
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    • 2013
  • The characteristics of the oceanographic environment in the Aleutian Basin of the Bering Sea during spring in 1996, 1997, and 1999 were clarified. An investigation of the water properties revealed five basic layers in the Bering Sea during spring: (1) a surface layer of warm and low-salinity water induced by solar heating, (2) a subsurface layer of cold and low-salinity water propagated slowly by heat from the surface layer, (3) a thermocline layer where salinity was constant but temperature sharply decreased, (4) a temperature inversion layer, and (5) a deep layer with a gradual decrease in temperature and increase in salinity toward the bottom. The ranges of water temperature and salinity were $1.8-5.5^{\circ}C$ and 31.81-34.08 in 1996, $1.5-7.2^{\circ}C$ and 31.9-34.06 in 1997, and $0.5-5.6^{\circ}C$ and 32.0-34.11 in 1999, respectively. The water temperature of the surface layer was approximately $1.6^{\circ}C$ higher in 1997 than in 1996 and 1999. The lowest temperature at a depth of 100-150 m was about $1^{\circ}C$ lower in 1999 than in 1996 and 1997. Nutrient levels (nitrate, phosphate, and silicate) contributing to the control of the growth of phytoplankton were higher in the Aleutian Basin than in the eastern continental shelf and Bogoslof Island area. This was closely associated with the phytoplankton distribution. Nutrient concentrations were lowest at a depth of 25 m. The high primary production at that depth was confirmed from the vertical distribution of chlorophyll a. Chlorophyll a levels were above $4.0{\mu}L^{-1}$ in some areas in 1996 and 1999, but below $2.0{\mu}L^{-1}$ in most areas in 1997. Zooplankton density was about three times higher in 1999 than in 1997.

An Analysis of Low-level Stability in the Heavy Snowfall Event Observed in the Yeongdong Region (영동지역 대설 사례의 대기 하층 안정도 분석)

  • Lee, Jin-Hwa;Eun, Seung-Hee;Kim, Byung-Gon;Han, Sang-Ok
    • Atmosphere
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    • v.22 no.2
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    • pp.209-219
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    • 2012
  • Extreme heavy snowfall episodes have been investigated in case of accumulated snowfall amount larger than 50 cm during the past ten years, in order to understand the association of low-level stability with heavy snowfall in the Yeongdong region. In general, the selected 4 events have similar synoptic setting such as the Siberian High extended to East Sea along with the Low passing by the southern Korean Peninsula, eventually inducing easterly in the Yeongdong region. Specifically moist-adiabatically neutral layer has been observed during the heavy snowfall period, which was easily identified using vertical profiles of equivalent potential temperature observed at Sokcho, whereas convective unstable layer has been formed over the East sea due to relatively warm sea surface temperature (SST) about $8{\sim}10^{\circ}C$ and lower temperature around 1~2 km above the surface, obtained from RDAPS. Difference of equivalent potential temperature between 850 hPa and surface as well as difference between air and sea temperatures altogether gradually increased before the snowfall period. Instability-induced moisture supply to the atmosphere from the East sea, being cooled and saturated by the upper cold surge, would make low-level ice cloud, and eventually move inland by the easterly flow. Heavy snowfall will be enhanced in association with low-level convergence by surface friction and upslope wind against Taebaek mountains. This study emphasizes the importance of low level stability in the Yeongdong region using the radiosonde sounding and RDAPS data, which should quantitatively be examined through numerical model as well as heat and moisture supply from the ocean.

Effects of Temperature and Salinity on Development of Sea Peach Halocynthia aurantium (붉은멍게 Halocynthia aurantium 발생에 관한 수온 및 염분의 영향)

  • Lee, Chu;Park, Min-Woo;Lee, Chae-Sung;Kim, Su-Kyoung;Kim, Wan-Ki
    • Journal of Environmental Science International
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    • v.18 no.10
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    • pp.1171-1179
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    • 2009
  • The solitary ascidian, Halocynthia aurantium, which is commonly called the sea peach because of its coloration and general shape, is a valuable organism of benthic marine population in the northern region of the East Sea, Korea. It is seldom found at a depth of less than 10 meters and the sea peach is frequently observed in large populations between 20 and 100 meters. It appears to prefer attachment to vertical rocks faces and artificial cement blocks exposed to the currents. Mass mortality and reduction of resources in sea peach, H. aurantium, were occurred in the benthic area of the northern region of the East Sea because of the rapid fluctuation of environmental factors such as temperature and salinity due to mass rainfall in summer and going up north of a strong warm current in winter. Therefore, we examined the effects of temperature and salinity on embryonic development of fertilized eggs, tadpole larva to metamorphosis, and attachment to siphon development. Laboratory-raised larvae were studied using a two-factorial experimental design with four levels of temperature(8, 12, 16 and $20^{\circ}C$) and four levels of salinity(20, 25, 30 and 34 psu). The ascidian larvae of H. aurantium survived environmental conditions between temperature of $8{\sim}20^{\circ}C$ and salinity of 25~34 psu and exhibited positive growth at $8{\sim}16^{\circ}C$ and 30~34 psu. Fertilized eggs have not developed at lower salinity of 20 psu irrespective of temperature range tested and have showed an abnormal development at the salinity of 25 psu between higher temperatures of 20 and $24^{\circ}C$. This result suggests that temperature increase and salinity reduction depending on environmental fluctuation may have significant impacts on population variation of H. aurantium in the northern region of the East Sea.

Commissioning result of the KSTAR in-vessel cryo-pump

  • Chang, Y.B.;Lee, H.J.;Park, Y.M.;Lee, Y.J.;Kwag, S.W.;Song, N.H.;Park, D.S.;Joo, J.J.;Moon, K.M.;Kim, N.W.;Yang, H.L.;Oh, Y.K.
    • Progress in Superconductivity and Cryogenics
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    • v.15 no.4
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    • pp.53-58
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    • 2013
  • KSTAR in-vessel cryo-pump has been installed in the vacuum vessel top and bottom side with up-down symmetry for the better plasma density control in the D-shape H-mode. The cryogenic helium lines of the in-vessel cryo-pump are located at the vertical positions from the vacuum vessel torus center 2,000 mm. The inductive electrical potential has been optimized to reduce risk of electrical breakdown during plasma disruption. In-vessel cryo-pump consists of three parts of coaxial circular shape components; cryo-panel, thermal shield and particle shield. The cryo-panel is cooled down to below 4.5 K. The cryo-panel and thermal shields were made by Inconel 625 tube for higher mechanical strength. The thermal shields and their cooling tubes were annealed in air environment to improve the thermal radiation emissivity on the surface. Surface of cryo-panel was electro-polished to minimize the thermal radiation heat load. The in-vessel cryo-pump was pre-assembled on a test bed in 180 degree segment base. The leak test was carried out after the thermal shock between room temperature to $LN_2$ one before installing them into vacuum vessel. Two segments were welded together in the vacuum vessel and final leak test was performed after the thermal shock. Commissioning of the in-vessel cryo-pump was carried out using a temporary liquid helium supply system.

A Study on the Sensitive Image of Pattern Applied Color & Formative Types of the Traditional Jokakbo (전통조각보의 색채, 면구성을 응용한 패턴의 감성이미지 연구)

  • Choi, Yoon-Hye;Eun, Young-Ja
    • Fashion & Textile Research Journal
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    • v.6 no.3
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    • pp.266-274
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    • 2004
  • This study is on the sensitive image of pattern expressed in the color & formative types of traditional Jokakbo(scraps of cloth). The object of this research is Korean traditional scraps of cloth in the latter period of Chosun Dynasty. This study is to be classified into 10 formative types like square type 1, square type 2, diagonal type, diamond type, many color striped type, concentric circle type, pinwheel type, vertical line type, cintamani pattern type, and free style type to apply the design of Jokakbo to Korean design. And color group is divided into vivid tone and pale tone. And it constitutes 17 patterns from the combination of these two types. As for the factors of constitution of scraps of cloth, it consists of factors like revelation, attraction, temperature sense, abstract, and rigidity. In the emotional image in the patterns, both vivid tone and pale tone showed dynamic and warm emotion together. Also, the factors of revelation and attraction were evaluated as opposite images, and it evaluated the plain and dim emotion as more attractive emotion. They preferred the pale tone to the vivid tone. They preferred the cintamani pattern in the vivid tone, and the diamond pattern in the pale tone most. From the research result above, this study made the abstract image of scraps of cloth standardized and prepared for a basis to execute it essentially. This research will be used as basic data to make traditional Korean image spotlighted in the world fashion markets as well as it will be helpful to the development of pattern design for the scraps of cloth essentially.

Distribution of Larvae of the Common Squid Todarodes pacificus in the Northern East China Sea (동중국해 북부해역에서의 살오징어(Todarodes pacificus) 유생의 분포)

  • Kim, Jung-Jin;Lee, Hwa-Hyun;Kim, Su-Am;Park, Chul
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.44 no.3
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    • pp.267-275
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    • 2011
  • The common squid Todarodes pacificus is an ecologically and commercially important species in Korea and Japan. However, the distribution pattern of its eggs and larvae in Korean waters has not yet been clarified. To determine the horizontal and temporal distribution of common squid larvae in the northern East China Sea, samples collected using paired, 60 cm diameter Bongo nets from the three surveys conducted in August 2003, May 2004 and November 2005 were examined. In addition, the vertical distribution was examined from the samples collected using a $1\;m^2$ MOCNESS in April 1999 (20 m interval down to 100 m). A total of 218 larvae ranging in mantle length (ML) from 1.2 to 17.0 mm were counted at 27 stations. Larval abundance was highest in May 2004. The larvae mainly occurred in the southeastern area of Jeju Island, where the water temperature and salinity at 50 m deep ranged from $15-23^{\circ}C$ and 34-34.6 psu, respectively. Most larvae were collected in the frontal zone, where the Tsushima Warm Current and inshore waters meet. The results from the MOCNESS samples showed that the larvae occurred mostly in 20-80 m depth ranges (about 90%), although collections were only conducted above 100 m. No significant differences in larval mantle lengths (ANOVA, P>0.05) were found among each depth interval. Given the occurrence sites of the larvae <2.0 mm ML, the spawning ground of this species appears to be within the northern East China Sea, mainly to the southeast and northeast of Jeju Island, in early spring.

Changes in the Characteristics of Wintertime Climatology Simulation for METRI AGCM Using the Improved Radiation Parameterization (METRI AGCM의 복사 모수화 개선에 따른 겨울철 기후모의의 특징적 변화)

  • Lim, Han-Cheol;Byun, Young-Hwa;Park, Suhee;Kwon, Won-Tae
    • Atmosphere
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    • v.19 no.2
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    • pp.127-143
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    • 2009
  • This study investigates characteristics of wintertime simulation conducted by METRI AGCM utilizing new radiation parameterization scheme. New radiation scheme is based on the method of Chou et al., and is utilized in the METRI AGCM recently. In order to analyze characteristics of seasonal simulation in boreal winter, hindcast dataset from 1979 to 2005 is produced in two experiments - control run (CTRL) and new model's run (RADI). Also, changes in performance skill and predictability due to implementation of new radiation scheme are examined. In the wintertime simulation, the RADI experiment tends to reduce warm bias in the upper troposphere probably due to intensification of longwave radiative cooling over the whole troposphere. The radiative cooling effect is related to weakening of longitudinal temperature gradient, leading to weaker tropospheric jet in the upper troposphere. In addition, changes in vertical thermodynamic structure have an influence on reduction of tropical precipitation. Moreover, the RADI case is less sensitive to variation of tropical sea surface temperature than the CTRL case, even though the RADI case simulates the mean climate pattern well. It implies that the RADI run does not have significant improvement in seasonal prediction point of view.

Remote Sensing of Surface Films as a Tool for the Study of Oceanic Dynamic Processes

  • Mitnik, Leonid;Dubina, Vyacheslav;Konstantinov, Oleg;Fischenko, Vitaly;Darkin, Denis
    • Ocean and Polar Research
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    • v.31 no.1
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    • pp.111-119
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    • 2009
  • Biogenic surface films, which are often present in coastal areas, may enhance the signatures of hydrodynamic processes in microwave, optical, and infrared imagery. We analyzed ERS-1/2 Synthetic Aperture Radar (SAR) and Envisat Advanced Synthetic Aperture Radar (ASAR) images taken over the Japan/East Sea (JES). We focused on the appearance of the contrast SAR signatures, particularly the dark features of different scales caused by various oceanic and atmospheric phenomena. Spiral eddies of different scales were detected through surface film patterns both near the coast and in the open regions of the JES in warm and cold seasons. During field experiments carried out at the Pacific Oceanological Institute (POI) Marine Station 'Cape Shults' in Peter the Great Bay, the sea surface roughness characteristics were measured during the day and night using a developed polarization spectrophotometer and various digital cameras and systems of floats. The velocity of natural and artificial slicks was estimated using video and ADCP time series of tracers deployed on the sea surface. The slopes of gravity-capillary wave power spectra varied between .4 and .5. Surface currents in the natural and artificial slicks increased with the distance from the coast, varying between 4 and 40 cm/s. The contrast of biogenic and anthropogenic slicks detected on vertical and horizontal polarization images against the background varied over a wide range. SAR images and ancillary satellite and field data were processed and analyzed using specialized GIS for marine coastal areas.

A Study of Pulse Diagnosis in "Onbyeongjobyeon(溫病條辨)" ("온병조변(溫病條辨)"에 나타난 맥진(脈診) 연구(硏究))

  • Kwon, Jung-Hyun;Baik, You-Sang
    • Journal of Korean Medical classics
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    • v.23 no.3
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    • pp.23-48
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    • 2010
  • Onbyeong(溫病) is called an acute epidemic febrile disease caused by warm pathogen, a major symptom of Onbyeong is high fever. Doctrine of Onbyeong is a study of an occurrence, progress and treatments of an acute epidemic febrile disease. Doctrine of Onbyeong is valid in the Cheong Dynasty at China. Now, a theory of doctrine of Onbyeong at China and Korea is being applied in not only an acute febrile disease but also many other lifestyle diseases. Onbyeongjobyeon is a book written by Oguktong(吳鞠通). Oguktong was influenced by Jangjung-gyeong(張仲景) "Sanghanron(傷寒論)". Oguktong had organized Seopcheonsa(葉天士)'s medical thoughts and Oguktong's medical experiences. A Samcho(三焦) deteriorated case is divided into three groups - Upper, Middle and Lower-energizer - that is discussed of a vertical progress of Onbyeong. And a Wigiyeonghyeol(衛氣營血) deteriorated case is divided into four groups - Wi, Gi, Yeong and Hyeol - that is discussed of a horizontal progress of Onbyeong. In Korean medicine, there are four types of diagnosis which are watching, listening, asking and taking. Informations, got by four types diagnosis are synthesized and classified for medical treatments. A pulse diagnosis belongs to a method by taking a wrist among four diagnosis. A Korean Medicine doctor makes a conclusion of cause, region and condition of disease by taking a pulse. Because all organs in human body are connected by a meridian system. organs conditions are reflected in a meridian system. So by taking a pulse, a progress and a prognosis of disease is diagnosed In this thesis, by taking a pulse on "Onbyeongjobyeon(溫病條辨)", a location and a feature of disease's cause with weakness and strength of a vital force are examined, and a character of a pulse diagnosis of Onbyeong is examined.

A Numerical Simulation Study Using WRF of a Heavy Snowfall Event in the Yeongdong Coastal Area in Relation to the Northeasterly (북동 기류와 관련된 영동해안 지역의 대설 사례에 대한 WRF수치모의 연구)

  • Lee, Jae Gyoo;Kim, Yu Jin
    • Atmosphere
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    • v.18 no.4
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    • pp.339-354
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    • 2008
  • A numerical simulation of a heavy snowfall event that occurred 13 January 2008 along the Yeongdong coastal area, was performed using WRF (Weather Research and Forecasting) in order to reveal mesoscale structures and to construct a conceptual model showing the meteorological background that caused the large difference in snowfall amounts between the Yeongdong mountain area and the Yeongdong coastal area. The simulation results matched well with various observations such as corresponding 12h-accumulated observed precipitation, surface wind obscrvation, radar echoes, and satellite infrared images. The simulation and the observations showed that the scale of the event was of meso - $\beta$ and meso - $\gamma$ scale. The simulation represented well the mesoscale process causing the large difference in snowfall amounts in the two areas. First, wind flow was kept, to a certain extent, from crossing the mountains due to the blocking effect of the low Froude number (~1). The northeast flow over the adjaccnt sea tumcd northwest as it approachcd the mountains, where it was trapped, allowing so-called cold air damming. Second, a strong convergence area formed where the cold northwest flow along the Yeongdong coastal area and the relatively warm and moist northeast flow advecting toward the coast met, supporting the fonllation of a coastal front. Thus, the vertical motion was strongest over the front located near the coast, leading to the heavy snowfall there rather than in the remote mountain area.