• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.29 no.1
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• pp.28-41
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• 2024

The carbon balance serves as a valuable indicator of a plant's physiological status under diverse environmental conditions. We investigated the photosynthetic and respiratory responses of the Asian surfgrass Phyllospadix iwatensis along the northeast coast of the Korean peninsula in response to changing water temperature (ranging from 5℃ to 30℃) to estimate the seasonal whole-plant carbon balance through a series of incubation experiments. The maximum gross photosynthetic rate (P_max) showed a significant difference among the temperature treatments, while there was no significant difference in photosynthetic efficiency (α). The maximum gross photosynthetic rate of P. iwatensis reached its peaks at 20℃ treatment (101.65 μmol O₂ g^-1 DW h^-1) but decreased rapidly at 30℃. The saturation irradiance (I_k), compensation irradiance (I_c), and respiration rate (R) of P. iwatensis exhibited significant differences among the temperature treatments. The saturation irradiance increased up to 20-25℃ (121.59-124.50 μmol photons m^-2 s^-1) and sharply decreased at 30℃. The compensation irradiance and respiration rate increased steadily with rising water temperature. The ratio of P_max to R (P_max:R ratio) was the highest at 5℃ but dramatically decreased at 30℃. The whole-plant carbon balance, calculated based on photosynthetic parameters, respiration rates, and biomass, exhibited distinct seasonal variation, increasing during winter and spring and decreasing during summer and fall, which is consistent with the highest in situ growth in spring and severely limited growth at the highest water temperature conditions. Phyllospadix iwatensis displayed a negative carbon balance during late summer, fall, and winter, but demonstrated a positive carbon balance during spring and early summer. Our findings suggest that the rising seawater temperatures associated with climate change may lead to significant alterations in the seagrass ecosystem functioning along the rocky shores of the Korean east coast.

• (The) Research of the performance art and culture
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• no.39
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• pp.279-323
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• 2019

The musical characteristics of Fishing songs in North Korean which recorded on Anthology of North Korean Folk Songs were examined in this paper. The results are as follows. Among Fishing songs in North Korea, there are "Rowing Song," the "Song for Hauling Nets," and the "Song for Picking Up Fish" in songs related to walleye pollack fishing and in songs related to croaker fishing, the "Song for Dropping Anchor" and the "Full-Load-of-Fish Song" in songs related to croaker fishing, the "Song for Weighing Anchor," the "Song for Shaking Fish," the "Full-Load-of-Fish Rowing Song," and the "Song for Hanging Walleye Pollack" in songs related to walleye pollack fishing. There are the "Song for Setting a sail" and the "Song for catching shells" in Fishing songs in North Korea, too. In the rhythmic elements of Fishing songs in North Korea, the tempo of the "Songs for Setting a sail" is moderato, and that of the "Songs for Picking Up Fish" of songs related to anchovy or herring fishing is quite slow. "Rowing Songs"(croaker fishing) have various tempos but faster than moderato, and usually get faster and faster as time goes by. Most songs have 4/♩. time and there are some of 2, 3 or 5 time. Some songs use irregular time or 6 time overlapping 2 beats. The mode Menari is the most common tonal system used in fishing songs of North Korea. And the mode Susimga, the mode Changbutaryeong, the mode Nanbongga, and the mode Odolttogi are also used in the tonal system of Fishing songs in North Korea. There are shoutting intonations that have indefinite pitch, too. Modulation or interaction by the mode Changbutaryeong appeared in songs of the mode Menari. There is a tendency to favor a certain tonal system by category. Responsorial form is mostly used, but in the most cases, they were sung in solo. In responsorial songs, several calling songs overlap with the responding songs. Durchkomponiert form is sung by antiphon or in solo, but the case sung in solo originally seems to have been sung by antiphon or unison, if we consider the procedure of the work. The "Song for Picking Up Fish" of Seonbong-gun of North Hamgyeong Province and Yangyang-gun of Gangwon Province, the "Full-Load-of-Fish Song-Bongjuktaryeong" of Jeungsan-gun of South Pyeongan Province and "Full-Load-of-Fish Song-Baechigisory" of Taean-gun of South Chungcheong Province, "Rowing Song" of Nampo City and Ganghwa-gun of Gyeonggi Province are resembled. In neighboring areas, even if the songs of different categorys, sometimes share a same melody. In a certain category, sometimes a same melody is shared to a considerable distance. It was first identified that in anchovy or herring fishing or dybowskii' sand eel fishing, the "Song for Picking Up Fish" is widely shared in the East Sea Coast area.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.5 no.2
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• pp.119-130
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• 2000

Mn, Zn, Cd and Pb in shells of Littorina brevicula, which lives ubiquitously in intertidal zone around the Korean coast, were analyzed to determine the relationship between metal levels in its shell, ambient seawater and its tissue. Periwinkles and seawater samples were collected from 38 sites along the Korean coast in January 1997. Mn contents in shells of this organism show the range of 7.0 ${\mu}g$/g-211 ${\mu}g$/g (mean 59 ${\mu}g$/g) and are the lowest in northern east coast but high in western south and west coast. Close relationship between Mn contents in shells and metal levels both in seawater and in tissues indicates that Mn in shell might be incorporated from ambient seawater by a biological process. Although the contents of Cd in shells did not reflect the distribution of total Cd in seawaters and they were very low compared to those in tissues, they followed spatial gradient of contents in tissues. However, the spatial distribution of Zn contents in shells accords neither ambient seawater nor tissues, while it is negatively correlated with the contents of Na in shells. This fact suggests that Zn contents might be controlled by salinity of ambient seawater. On the contrary, Zn contents in highly polluted sites near Onsan Bay show generally higher levels than other sites. The contents of Pb show the range of 0.1 ${\mu}g$/g-17.5 ${\mu}g$/g (mean 1.01 ${\mu}g$/g) and the highest in sites near Onsan Bay. Although the spatial distribution of shell Pb does not follow those of tissue, Pb in shells of Littorina brevicula may be controlled both by shell secretion process and by Pb levels in ambient seawater because the contents of Pb in the shell decrease steadily with growth and vary with levels of Pb in ambient seawater.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.22 no.5
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• pp.266-280
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• 1989

Gonadal maturation of the Korean pomfrets, Pampus echinogaster (Basilewsky) and Pampus argenteus (Euphrasen) were histologically investigated based on the samples captured in the East China Sea from January 1987 to December 1988. Gonadosomatic index (GSI) of P. echinogaster began to increase from March, and reached maximum between May and July. It began to decrease from July and reached mini-mum between August and February. P. argenteus had a similar cycle, however, P. argenteus has higher values in April than P. echinogaster. Hepatosomatic index (HSI) were positively related to GSI. HIS of P. echinogaster and P. argenteus reached maximum in $April\~July$ and $April\~August$, respectively, Fatness coefficient of two Pampus species were low in the summer, and high in the winter. Ovary is of saccular structure, and testis is of lobular structure. From February, the early oocyte (ca. $100\mu$ in diameter grows) rapidly at the germinal epithelium of ovarian sacs. From March to April the oocytes grew up to cu $400\~500\mu$ in diameter. At this stage, the yolk globules are accumulated rapidly in the cytoplasmic layer. From May, the oocytes roached ca. $650\~850\mu$ in diameter, and they are spawned in $May\~July$. After spawning the residual follicles and remained ripe eggs degenerate. From February, spermatogonia grows into spermatocyte on the epithelium of the testicular lobuli. From May, spermatozoa appeared and spawning occurs. After spawning, the epithelium is thickened and the remained spermatozoa degenerate. Annual reproductive cycle of two Pampus species could be divided into four successive stages: Growing stage ($March\~April$), Mature stage ($April\~May$), Ripe and spent stage ($June\~July$) and Recovery and resting stage ($August\~January$). Absolute fecundity of P. echinogaster was $9,441\~135,294$, and that of P. argenteus was $50,678\~221,894$. Absolute fecundity of two Pampus species were positively related to body length and total weight. Relative fecundity was positively related to body length, while it was reversely related to total weight. The increasing rate of absolute fecundity of P. echinogaster was lower than P. argenteus. In P. echinogaster half of female and male reached first maturity at body length of $15.0\~$17.9cm and $12.0\~14.9cm$, respectively. All of females and males reached first maturity at body length of $18.0\~20.9cm$ and $21.0\~23.9cm, respectively. In P. argenteus all of females and males reached first maturity at body length of 18.6cm and 16.7cm$, respectively.

• Korean Journal of Remote Sensing
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• v.39 no.6_1
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• pp.1255-1272
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• 2023

Satellite-based chlorophyll-a concentration, produced as a long-term time series, is crucial for global climate change research. The production of data without gaps through the merging of time-synthesized or multi-satellite data is essential. However, studies related to satellite-based chlorophyll-a concentration in the waters around the Korean Peninsula have mainly focused on evaluating seasonal characteristics or proposing algorithms suitable for research areas using a single ocean color sensor. In this study, a merging dataset of remote sensing reflectance from the geostationary sensor GOCI-II and polar-orbiting sensors (MODIS, VIIRS, OLCI) was utilized to achieve high spatial coverage of chlorophyll-a concentration in the waters around the Korean Peninsula. The spatial coverage in the results of this study increased by approximately 30% compared to polar-orbiting sensor data, effectively compensating for gaps caused by clouds. Additionally, we aimed to quantitatively assess accuracy through comparison with global chlorophyll-a composite data provided by Ocean Colour Climate Change Initiative (OC-CCI) and GlobColour, along with in-situ observation data. However, due to the limited number of in-situ observation data, we could not provide statistically significant results. Nevertheless, we observed a tendency for underestimation compared to global data. Furthermore, for the evaluation of practical applications in response to marine disasters such as red tides, we qualitatively compared our results with a case of a red tide in the East Sea in 2013. The results showed similarities to OC-CCI rather than standalone geostationary sensor results. Through this study, we plan to use the generated data for future research in artificial intelligence models for prediction and anomaly utilization. It is anticipated that the results will be beneficial for monitoring chlorophyll-a events in the coastal waters around Korea.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.25 no.3
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• pp.147-153
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• 2013

There exist various types of the WEC (Wave Energy Converter), and among them, the point absorber is the most popularly investigated type. However, it is difficult to find examples of systematically measured data analysis for the design of the point absorber type of power buoy in the world. The study investigates the wave load acting on the point absorber type resonance power buoy wave energy extraction system proposed by Kweon et al. (2010). This study analyzes the time series spectra with respect to the three-year wave data (2002.05.01~2005.03.29) measured using the pressure type wave gage at the seaside of north breakwater of Hupo harbor located in the east coast of the Korean peninsula. From the analysis results, it could be deduced that monthly wave period and wave height variations were apparent and that monthly wave powers were unevenly distributed annually. The average wave steepness of the usual wave was 0.01, lower than that of the wind wave range of 0.02-0.04. The mode of the average wave period has the value of 5.31 sec, while mode of the wave height of the applicable period has the value of 0.29 m. The occurrence probability of the peak period is a bi-modal type, with a mode value between 4.47 sec and 6.78 sec. The design wave period can be selected from the above four values of 0.01, 5.31, 4.47, 6.78. About 95% of measured wave heights are below 1 m. Through this study, it was found that a resonance power buoy system is necessary in coastal areas with low wave energy and that the optimal design for overcoming the uneven monthly distribution of wave power is a major task in the development of a WEF (Wave Energy Farm). Finding it impossible to express the average spectrum of the usual wave in terms of the standard spectrum equation, this study proposes a new spectrum equation with three parameters, with which basic data for the prediction of the power production using wave power buoy and the fatigue analysis of the system can be given.

• Sijohaknonchong
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• v.25
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• pp.175-209
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• 2006

This study focuses on Korean-American writer Hong-Eun$(1880{\sim}1951)'s$ American travel gasaes and sis who played an active role under the rule of Japanese imperialism. This study also investigates Hong-Eun's experience and expression on American travel and culture and discusses his changes in stream of consciousness. According to American travel sigaes which were published in the New Koren Times in 1936. 1937, and 1949, his consciousness can be summarized as follows. First travel siga depicts his inner conflict as a refugee who lost one's home country. That is to say. by observing Indians' losing identity and their miserable labor conditions, he developed his own critical eyes on American society. Eventually he missed his country desperately and sought for the ways of his returning there. Second travel sijo reveals his own agony about not be able to return his home country where he could Possibly visit. In other words, after suffering from his agony, it is evident that he started to take positive attitude towards American society and establish his own identity. Based upon Hong-Eun's changes in consciousness as a writer, the researcher hypothesizes that there exists Diaspora-Consciousness in his work. His consciousness is strongly related with his attitude towards his home country whether it Is positive or vice versa. When his home country declared her independence. his attitude towards immigrant society was positively changed, which was quite contradictory from his previous one. In this transition period, not only he accepted American ideology and life, but he re-conceptualized them as a Korean mode. In sum, Hong-Eun's mental traces lie on the core of hybrid and diaspora which Post-Colonial literature values highly of.

• Korean Journal of Environment and Ecology
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• v.36 no.2
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• pp.118-138
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• 2022

This study was conducted to identify the vegetation structure of major vegetation by region and elevation in the subalpine zone of Seoraksan National Park and prepare an inventory of flora. We reviewed the results of the previous subalpine studies and, through a preliminary survey, determined that the first appearance point of subalpine vegetation was about 800 m based on the south. Then we conducted a site survey by installing a total of 77 plots, including 12 plots on the northern Baekdamsa-Madeungnyeong trail (BD), 13 plots on the west Hangyeryeong-Kkeutcheong trail (HG), 13 plots on the east side of Sinheungsa-Socheongbong trail (SA), and 39 plots in the southern Osaek-Kkeutcheong, Osaek-Daecheongbong trail (OS), in an interval of 50 m above sea level. The analysis classified 7 communities, including Qercus mongolica-Abies holophylla-Acer pseudosieboldianumcommunity, Q. mongolica-Tilia amurensiscommunity, Q. mongolica-Pinus koraiensiscommunity, Q. mongolica-A. pseudosieboldianumcommunity, Betula ermanii-A. nephrolepiscommunity, P. koraiensis-A. nephrolepiscommunity, and mixed deciduous broad-leaf tree community according to the species composition based on the appearance of the major subalpine plants such as Quercus mongolica, Betula ermanii, and Abies nephrolepis, region, and elevation. 10.68±2.98 species appeared per plot (100 m²), and 110.87±63.89 individuals were identified. The species diversity analysis showed that the subalpine vegetation community of Seoraksan National Park was a mixed forest in which various species appeared as important species. Although there was a difference in the initial elevation for the appearance of major subalpine plants by region, they were distributed intensively in the elevation range of 1,100 to 1,300 m. In the Seoraksan National Park, 322 taxa, 83 families, 193 genera, 196 species, 1 subspecies, 26 varieties, and 4 forms of vascular plants were identified. One taxon of Trientalis europaeavar.arcticawas identified as the protected species. The endemic plants were 19 taxa, and 58 taxa were identified as subalpine plants.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.17 no.3
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• pp.139-148
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• 2012

The short-term variation of salinity and temperature in a dyked estuarine environment is mainly controlled by the freshwater discharge from the dyke. We examined the distribution of salinity and temperature by the freshwater discharge in the Yeongsan River estuary using the CTD data obtained from 8 stations through three surveys in June (weak discharge) and August (intensive discharge), 2010. During the weak discharge in June, the surface salinity showed 30-32.5 psu and its horizontal gradient was relatively high around Goha-do (0.25~0.32 psu/km). On the other hand, the salinity of the bottom layer was almost constant in the range of 33 psu. Water temperature ranged $19{\sim}21^{\circ}C$ and displayed higher gradient in north-south direction than the gradient of east-west direction. During the intensive freshwater discharge on August 12, the salinity dropped to 9~26 psu. The maximum horizontal gradient of surface salinity reached 3.8 psu/km in the north of Goha-do where the strong salinity front was formed, and the horizontal salinity gradient of bottom layer was 0.28 psu/km. The horizontal gradient of water temperature was $-0.45^{\circ}C/km$ in the surface and $-0.12^{\circ}C/km$ in the bottom with high surface temperature near the dyke and decreasing gradually to the river mouth. After 3 days of the intensive discharge ($3^{rd}$ survey), the surface salinity increased to 22~26 psu. However, there still existed relatively high horizontal gradient around Goha-do. In the mean time, the bottom salinity decreased to 26.5~27.5 psu, but its gradient was not big as much as the surface gradient. According to time series of CTD profile near the dyke, the discharged fresh water jetted down temporarily and then recovered gradually with the recovering speed of 0.4 m/hour for the discharge case of $13{\times}10^6$ ton. Due to the combined effects of freshwater discharge and surface heating during the summer of 2010, the Yeongsan estuary, in general, underwent intensified vertical stratification, which in turn caused the inhibition of vertical mixing, especially inside area of estuary. Based on the spatial distribution of salinity and temperature, the Yeongsan estuary can be divided into three regions: the Goha-do area with strong horizontal gradient of salinity and temperature, inner estuary from Goha-do to the dyke with low salinity, and outer estuary from Goha-do to the coasts with relatively high salinity.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.28 no.6
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• pp.812-813
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• 1995

Lactococcal cells are nutritionally fastidious and thus, generally cultured either in milk or M17 medium (Terzaghi and Sandine, 1975). In this study, Lactococcus cremoris wild-type (KH) and its less­proteolytic mutant (KHA1) cells were grown on the M17 medium or with modified M17 medium by replicated parallel experiments. The modified M17 medium had the same composition as M17 medium, except that lactose was replaced by glucose. Analyses of culture-broth samples, in which the M17 and the modified M17 media were used, were conducted by high-performance liquid chromatography (HPLC). But, working with these media created noisy problems in analyses of samples. Therefore, a new semi-synthetic medium was developed on the basis of nutritional requirements (Morishita et al., 1981). The composition of the semi-synthetic medium determined on the basis of the nutritional requirements and the composition of milk, is presented in Table 1. The composition of M17 medium is also presented and compared in the table. L. cremoris KH and KHA1 cells were grown again on the new synthetic medium containing glucose or lactose. The broth samples were then drawn and analyzed by HPLC. Clearer separations of fermented products were achieved from the new medium than those with the M17 and the modified M17 media. In comparison with the M17 or the modified M17 media, growth on the new medium was good (Kim et al, 1993). Additional fermentations were also carried out at a controlled pH of 7.0, where enhanced growth of lactococcal cells was obtained. In the fermentations, samples were also analyzed for the concentrations of sugar and lactic acid. The results showed that the new synthetic medium was as good as or better than the M 17 and the modified M 17 media. This is because casein hydrolysate in the synthetic medium provided a ready supply of amino acids and peptides for L. cremoris KH and KHA1 cells. Lactic acid bacteria (LAB) including Lactococcal cells have been known to be an effective means of preserving foods, at the same time as giving particular tastes in fields of dairy products. LAB also have always occupied an important place in the technology of sea products, and marine LAB have known to be present in traditional fermented products (Ohhira et al, 1988). To apply the new synthetic medium to marine LAB, two different LAB were isolated from pickled anchovy and pollacks caviar and were grown on the new media in which various concentrations of NaCl $(3, 5, 7 and 10\%)$ added. They were also grown on the medium solution in natural seawater $(35\%o\;salinity)$ and on the solution of natural seawater itself, too. As seen in Fig. 1, Marine LAB were grown best on the synthetic medium solution in natural seawater and the higher concentrations of NaCl were added to the medium, the longer lag-phase of growth profile appeared. Marine LAB in natural seawater were not grown well. From these results, the synthetic medium seems good to cultivate cells which are essential to get salted fish aged. In this study, it showed that the new synthetic medium provided adequate nutrition for L. cremoris KH and KHA1 cells, which have been used as cheese starters (Stadhouders et al, 1988). Using this new medium, the acid production capability of starter cultures could be also measured quantitatively. Thus, this new medium was inferior to the M17 or the modified M17 medium in culturing the cheese starters and in measuring fermentation characteristics of the starter cells. Moreover, this new medium found to be good for selected and well-identified marine LAB which are used in rapid fermentations of low-salted fish.