• Title/Summary/Keyword: warm current

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The Relationship between Oceanographic Condition and Fishing Ground Distribution of Yellow Croaker in the East China Sea and the Yellow Sea (동지나해, 황해의 참조기 어장분포와 해황과의 관계)

  • YANG Seong-Ki;CHO Kyu-Dae
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.15 no.1
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    • pp.26-34
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    • 1982
  • The East China Sea and the Yellow Sea are abundant in nutritions because of river inflows and are important as the nursery and spawning grounds of demersal and pelagic fishes. The remarkable thermal front between the Yellow Sea Bottom Cold Water and the Tsushima Warm Current is formed in this region, and the fluctuation of this front may affect the variation of the yellow croaker fishing ground. To investigate the mechanism of the yellow croaker fishing ground, the distribution ana seasonal change of the fishing ground are examined by using catch of stow net fishery (Fisheries Research and Development Agency, 1970-1979) and the water temperature data (Japan Hydrographic Association, 1978). The main fishing ground of yellow croaker was nine sea areas (rectangle of 30' latitude by 30' longitude) located at 40-150 nautical miles west and southwest of Jeju Island, the area of which occupies no more than $11\%$ of all fishing grounds, and it appeared that about $70\%$ of total catch of ten years was concentrated in this area. The main fishing periods were from March to May and September to October. The coefficients of variation of the catch for the main fishing ground were from 0.8 to 2.1 and the condition of all fishing grounds was generally unstable. The mean CPUE was 27kg/haul at the main fishing ground, while it was the largest on boundary area of the Yellow Sea Bottom Cold Water. It was found that the seasonal movement of fishing ground is related to the expansion and reduction of the Yellow Sea Bottom Cold Water ($10^{\circ}C$).

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A Study on Identity of Home Economics Education : Focusing on the Image and the Characteristics (가정과교육의 정체성 탐색 : 이미지와 성격을 중심으로)

  • Park, Mi-Jeong;Chae, Jung-Hyun
    • Journal of the Korean Home Economics Association
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    • v.45 no.4
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    • pp.1-16
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    • 2007
  • The purpose of this study was to explore the identity of home economics(HE) education by assessing perceptions of HE teacher, students, and general adults regarding the images and characteristics of HE education. Respondents in this study were 234 HE teachers, 505 students, and 264 general adults. Questionnaires were collected through both online and offline. The image and the characteristics of HE education were the factors of the identity that were also the byproducts of HE education operation of the past and present, and had the characteristics in changing in accordance with the change of time. The current image of HE education was shown to positive recognition as the curriculum helpful to the actual living and future living for the HE teacher, students, and the general adults. For the HE teacher, it had strong emotionally warm image similar to the image of 'home', and it was connected to the curriculum image to be acknowledged as good problem solving teachers in terms of competence and conservative image. However, on the images of the HE curriculum and HE teacher, the HE teachers had the most positive recognition, and on the image of the HE curriculum, the students had the most negative recognition while the image of the HE teacher, the general adults had the most negative recognition. The general adults among the three groups recognized the HE curriculum as the most technical oriented curriculum while the students recognized as interesting curriculum, curriculum contributing on society. In the meantime, for the characteristic of the HE education, the HE teachers recognized that it had weak female curriculum characteristics and strong living functional curriculum characteristics, and the practical curriculum characteristics would be important in the future. Accordingly, the identity of the HE education formulated might be considered as the practical curriculum that was helpful to problem solving in actual living of the family and family members with the connection to the concept of 'home'. However, depending on the definition on implication of practice and issue of actual living, the characteristics and appearance of the HE education had been changed and might interpret as changing according to the above.for the fertility policy and the methods for the estimation of the child cost were suggested based on the results.

The Marine Environment and Dinoflagellates Cysts in the Southwestern Sea of Korea (한국남서해역의 해양환경과 와편모조류 시스트 분포 특성)

  • Park, Jong-Sick;Yoon, Yang-Ho;Noh, Il-Hyeon;Soh, Ho-Young;Shin, Hyeon-Ho
    • ALGAE
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    • v.23 no.2
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    • pp.135-140
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    • 2008
  • A field survey for dinoflagellate cysts was carried out from May 2000 to November 2002 for the Southwest Sea of Korea. A total dinoflagellate cysts identified were 33 species, which belonged to 17 genera, 31 species, and 2 unidentified species. A cysts density were 16-1,501 cysts-gdry$^{-1}$. The dominant species of dinoflagellate cysts in the Southwestern Sea of Korea were Spiniferites bulloideus and Scrippsiella trochoidea, which are autotrophic species. To investigate the environmental characteristics of the Southwestern Sea of Korea using the dinoflagellate cysts, a principal component analysis (PCA) was conducted using the data collected from a total of 51 stations. From the score distribution map by the PCA, the Southwestern Sea of Korea was largely divided into three regions according to the first primary component and the second primary component. In other words, Group 1 was the western sea area of Mokpo and Jindo, Group 2 was the outer sea area of the South Sea, and Group 3 was the coastal areas of the South Sea around the Archipelago. It was found that this division of sea area was influenced by effects of the sea environment of the coastal areas of Korea. The coastal areas of Mokpo and Jindo that belong to Group 1 were affected by the cold Yellow Sea water. The outer sea area of the central parts of the South Sea that belong to Group 2, which is the boundary between the Southern coastal water of Korea and the Tsushima warm water, was subject to the formation of temperature fronts throughout the year, while Group 3 was affected by the coastal waters of Korea. It was also found that this division was in close relationship with the distribution of sediment facies in the bottom layer. From the above results, the environmental factors that influence the cyst distribution in he Southwestern Sea of Korea were found to include the eutrophication status of the sea area, the physical characteristics of the sea environment such as the flow of sea current and fronts, the sediment facies in the bottom layer, and the appearance volume of motile cells.

Empirical Orthogonal Function Analysis on the Monthly Variation of Flow Pattern in the East Sea of Kore (경험적 고유함수법에 의한 한국동해 해황변동해석)

  • CHANG Sun-Duck;LEE Jong-Sup;SUH Jong-Moon
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.21 no.6
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    • pp.323-330
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    • 1988
  • The spatial distribution of sea water temperature variation pattern in the South-eastern coastal region of Korea was studied by empirical orthogonal function (E. O. F) analysis in several depths from surface to 300m using the monthly mean water temperature averaged for 23 years, water mass analysis by T. S diagram and sectional diagram of water temperature. Typical type of water temperature variation in this area can be divided into surface (0m-50m), subsurface (100m-150m) and intermediate (200m-300m) layer. The first mode value of water temperature change on the surface layer showed $99\%$ of total variation, and decreased with the increase of the depth. It is deduced to be in the range of $60-70\%$ on the 300m layer. The representative type of water temperature fluctuation by the first mode in each layer is as follows. Water temperature change in the surface layer showed a seasonal variation. In the subsurface layer, it is governed by the interaction of the Tsushima Warm Current water with the cold water and by the heat transfer process from the upper layer. In the intermediate layer, water temperature variation seems to be governed by the advection of the bottom cold water.

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Niche characterization of the tree species of genus Ophiura (Echinodermata, Ophiuroidea) in Korean waters, with special emphasis on the distribution of Ophiura sarsi vadicola Dja (한국산 빗살거미불가사리 3종의 서식처 지위- 특히 Ophiura sarsi vadicola Djakonov의 분포를 중심으로)

  • 홍재상;유재원
    • 한국해양학회지
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    • v.30 no.5
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    • pp.442-457
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    • 1995
  • The relationships of environmental factors to the distribution patterns of the three species of ophiuroids, Ophiura kinbergi, O. sarsi and ). sarsi vadicola from Yellow Sea southeast seas and East Sea of Korea were studied to characterize their habitual niches. These three species chosen for study illustrated distinct niche and patterns according to their various preferences mainly for bottom water temperature, bottom water salinity and depth from seven environmental variables which were depth, bottom water temperature and salinity, density, bottom water oxygen content, grain size of the surface sediment, and sediment sorting coefficient. The results of habitat niche study mainly dealing with O. sarsi vadicola suggested that the optimum habitat rages were approximately 6$^{\circ}C$∼10$^{\circ}C$ in bottom temperature and 31%∼33.5% in bottom water salinity which also corresponded with the characteristic ranges of Yellow Sea Bottom Cold Water and higher probabilities of occurrence (more than 70%) were found in depth ranging from 100 to 200 m. In addition, the habitats of O. kinbergi and O. sarsi were compared with that of O. sarsi vadicola. Their ranges of habitat niches were found to have different niches in physical space of bottom water temperature, bottom water salinity and depth. Based on the distribution pattern of O. sarsi vadicola in the Yellow Sea, the ecological barrier which confined the distribution of benthic macro-invertebrates in southern Yellow Sea was determined to be the Yellow Sea Warm Current (approximately 34% < and 18$^{\circ}C$ in December) which occurs between 33$^{\circ}$ and 34$^{\circ}$N of southern Yellow Sea in winter time.

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Metagenomic Approach on the Eukaryotic Plankton Biodiversity in Coastal Water of Busan (Korea) (부산 연안역의 진핵플랑크톤 종다양성에 대한 메타게놈 분석 연구)

  • Yoon, Ji-Mie;Lee, Jee-Eun;Lee, Sang-Rae;Rho, Tae-Keun;Lee, Jin-Ae;Chung, Ik-Kyo;Lee, Tong-Sup
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.17 no.2
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    • pp.59-75
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    • 2012
  • The species composition of plankton is essential to understand the material and energy cycling within marine ecosystem. It also provides the useful information for understanding the properties of marine environments due to its sensitivity to the physicochemical characteristics and variability of water masses. In this study we adopted metagenomics to evaluate eukaryotic plankton species diversity from coastal waters off Busan. Characteristics of water masses at sampling sites is expected to be very complex due to the mixing of various water masses; Nakdong River runoff, Changjiang diluted water (CDW), South Sea coastal water, and Tsushima warm current. 18S rDNA clone libraries were constructed from surface waters at the three sites off Busan. Clone libraries revealed 94 unique phylotypes from 370 clones; Dinophyceae(42 phylotypes), Ciliophora(15 phylotypes), Bacillariophyta(7 phylotypes), Chlorophyta(2 phylotypes), Haptophyceae(1 phylotype), Metazoa(Arthropoda( 17 phylotypes), Chaetognatha(1 phylotypes), Cnidaria(2 phylotypes), Chordata(1 phylotype)), Rhizaria (Acantharea(2 phylotypes), Polycystinea(1 phylotype)), Telonemida(1 phylotype), Fungi(2 phylotypes). The difference in species diversity at the closely located three sites off Busan may be attributed to the various physicochemical properties of water masses at these sites by the mixture of water masses of various origins. Metagenomic study of species composition may provide useful information for understanding marine ecosystem of coastal waters with various physicochemical properties in the near feature.

Inversion Phenonena of Temperature Off East Cheju Island in Summer , 1986 (1986년 하계 제주도 동부 해역의 수온 역전 현상)

  • Jo, Gyu-Dae;Park, Seong-U
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.26 no.3
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    • pp.265-274
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    • 1990
  • The temperature inversions were studied on the basis of Digital Memory Bathythermography(DBT) data collected by training ship, Pusan 402, of the National Fisheries University of Pusan in August 23~25, 1986 and Fisheries Reserach and Development Agency of Korea in August, 1986, The results were as follows; Among the 67 stations of studied area, occurrence frequency of temperature inversion was 58.20%, And the frequency of onefold occurrence of temperature inversion at its profile of each station was 13.42%. of twofold occurrence was 20.80%, and of threefold occurrence was 23.88%. In the studied area, the temperature inversion usually occurred below the 40m depth and its layers also located below the thermocline. The temperature range of its inversion was from 14$^{\circ}C$ to 16$^{\circ}C$. The temperature inversion in the study area was oaused by the interaction between Tsushima Warm Current and Korea Coastal Waters.

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Seasonal Distribution of Oceanic Conditions and Water Mass in the Korea Strait and the East China Sea: Correction of Atmosphere Cooling Effect (대한해협과 동중국해의 해황과 수괴의 계절분포: 대기에 의한 냉각효과 보정)

  • Shin, Hong-Ryeol;Hwang, Sang-Chul;Kwak, Chong-Heum
    • Journal of the Korean earth science society
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    • v.22 no.1
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    • pp.47-64
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    • 2001
  • Water mass classification was conducted using the data of 1985 and 1986 in the East China Sea and the Korea Strait. Kuroshio water (type K) and mixed water (type I) were broadly distributed at 50 m depth in winter and spring, and mixed waters (type I to IV) were distributed in summer and autumn. At 100 m depth of the East China Sea, and mixed water (type I) was broadly distributed in winter and spring, and mixed waters (type I to III) were in summer, and type I was in autumn. Water mass in summer is the most influenced from the Chinese coastal water. In the Korea Strait, the Kuroshio water (type K) was the main water mass in winter and spring, and mixed waters (type I to IV) were in summer and autumn. If temperatures are corrected to remove the cooling effect from the atmosphere, the Kuroshiowater region was diminished, however the mixed water region was expanded in winter and spring. This shows that although the Kuroshio water appears to be a main water mass of the East China Sea and the Korea Strait in winter andspring, in reality the mixed water (type I) which is slightly changed from the Kuroshio water (type K) widely distributed. The tongue-shaped distribution of low density surface water indicates that the water mixed with the Chinese coastal water flows to the Korea Strait and the Okinawa in summer.

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The Effects of Mothers' Parenting Stress on Chilren's Learning Readiness Mediating Effects of Paren-Child Interactions and Parental Attitudes (어머니의 양육 스트레스가 아동의 학습준비도에 미치는 영향: 부모-자녀 상호작용과 온정적 양육태도의 매개효과)

  • Kim, Yeoung-Mi
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.12
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    • pp.563-573
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    • 2019
  • The purpose of this study is to confirm whether the parenting stress of mothers with preschool children mediated the parent-child interaction and parenting attitude on children's learning readiness. Data was used from the 5th (2012) to 7th (2014) Korean Children's Panel, and a total of 1,480 data sets were used for the analysis. The age of study participants was five years old. The Amos 23.0 program was used as an analytical tool, and the structural equation model analysis was applied to estimate the path coefficient corresponding to the research question. First, it was expected that mothers' parenting stress negatively affected the parent-child interaction, mother's parenting attitude, and children's readiness. Second, it was assumed that parent-child interaction and the mother's warm parenting attitude were positively significant to children's readiness. Third, the relationship between the parenting stress of mothers and children's learning readiness was partially mediated by a positive parenting attitude. The current study supplies valuable data to establish the educational support and efficiency strategy for domestic children. This study is meaningful in that it provides basic data in preparing a plan to more effectively provide educational support for domestic children.

The Development of the Hantan River Basin, Korea and the Age of the Sediment on the top of the Chongok Basalt (한탄강유역의 발달과정과 전곡현무암 위의 퇴적물의 연대)

  • Bae, Kidong
    • The Korean Journal of Quaternary Research
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    • v.3 no.1
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    • pp.87-101
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    • 1989
  • The development of the Hantan river basin can be divided into three stages. The first stage include the ancient Hantan channel system prior to the Chongokni basalt which yield dates of about 0.6 mya from the K/Ar dating method. During this period the Baekuyri formation was formed. The Baekuyri formation is widely observed under the Chongokni basalt along the current river system. The second stage is the period when stream channels stayed on the top of the basalt plateau. Aggradation and deggradation were continued by meandering and braiding channel systems until major stream channel was formed. The currently remaining deposit on the top of the basalt was formed by lacustrine and fluvial systems in this period. During this period Pleistocene hominid was present on edge of water and flood plain and left Paleolithic material. This period was begun at the time of the final basalt flow dated about 300,000 BP. The third stage is designed for the time when the Hantan river channel was dropped down to a level from which the channel could not influence the top of the basalt any more No more deposit could be formed but erosion by surface water has been continued on the top of the basalt since then. The dropping of the Hantan river channel was probably not very long after the final flow of the basalt. Because of frost action and heavy concentrated precipitation in the basin area along with blocky and clumnar joint structure of the basalt, erosional process of the basalt is believed to have been carried out within a relatively short time. The lowering of the Hantan river channel was probably completed in a cycle of major fluctuation of world cimate. Also, the redclay on the top of the basalt is believed to have been formed during a warm period around 200,000 BP, which accords with the climatic change suggested above fair1y well. The Paleolithic materials in tile deposits fell accordingly into approximately same time period.

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