• Journal of the korean society of oceanography
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• v.38 no.3
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• pp.122-134
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• 2003

Low-pass filtered time series of wind, coastal temperature, sea level and current were analyzed to understand the coastal upwelling processes in the southeast coast of Korea. Southerly winds favorable for coastal upwelling were dominant in summer of 1997. Total period of four major wind events amounts to 58 days during one hundred days from June to early September. Coastal temperature is most sensitive to variations of wind. The time lag between the onset of southerly (northerly) winds and decrease (increase) of temperature is 3-18 hours. In the frequency domain the coherent bands have periods of 2.4 and 4.0-5.4 days with respective phase lags of 17 and 27-37 hours. Despite the sensitive response, the magnitude of temperature change is not quantitatively proportional to the intensity or duration of the wind, because it depends on the degree of baroclinic tilting of isotherms built dynamically by the strong Tsushima Warm Current (TWC). Current is particularly strong near the coast and has a large vertical shear during the upwelling periods, which is associated with the baroclinic tilting. Both of current and sea level are poorly coherent with wind or temperature except for the period of 4 days.

• Korean Journal of Plant Resources
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• v.19 no.6
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• pp.687-691
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• 2006

This experiment was conducted on rice (cv. 2005 Thaoi) seeds to study whether priming with deep sea water (DSW) results in enhancement of seed emergence and seedling growth and to identify the optimum concentration of Deep Sea Water (DSW) for priming. Two experiments were conducted subsequently. In experiment 1, four concentrations of the DSW (10%, 20%, 30% and 40%), and in experiment 2, five concentrations of DSW (10%, 15%, 20%, 25% and 30%) were prepared and seeds were primed for 24 hours duration at $25^{\circ}C$. Beside this, hydro priming with plain water was also included as a control. Experiments were laid out in Completely Randomized Design (CRD) with three replications. Result showed that 20% DSW seed priming treatment had improved the emergence, seedling height, number of roots and root length as compare to other with DSW or without DSW treatments. Beyond 20% DSW priming (i.e. 25%, 30% and 40%) were not suitable for priming the seed. On the basis of seedlings growth parameters; emergence, seedling height, root number and length, and shoot root ratio, 20% DSW priming was the best priming treatment.

• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.222-222
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• 2015

Vietnam is one of the most vulnarable countries affected by climate change and sea level rise. One of the consequences of climate change and sea level rise is the increase of salinity intrusion into the rivers which is challenging to irrigation systems in coastal areas. This indicates the necessary to study the ability of taking water through sluice gates of irrigation systems in coastal zones, especially in the dry season with the effects of climate change and sea level rise in the future. In this paper, Nam Thai Binh irrigation system is selected as a case study. The irrigation system is one of 22 biggest irrigation systems of the Red River delta in Vietnam located in coastal region. The computed duration is selected in dry season to irrigate for Winter-Spring crops. The irrigation water for the study area is taken from different sluice gates along the Red River and the Tra Ly River. In this paper, MIKE-11 model was applied to assess the ability of taking water for irrigation of the study area in current situation and in the context of climate change and sea level rise senario in 2050 (under the medium emissions scenario (B2) published by the Ministry of Natural Resources and Environment of Vietnam published in 2012) with different condition of water availability. The operation of the gates depends on the water levels and sanility conditions. The sanility and water level at different water intake gates of Nam Thai Binh irrigation system were simulated with different senarios with and without climate change and sea level rise. The result shows that, under climate change and sea water level rise, some gates can take more water but some can not take water because of salinity excess and the total water taking from the different gates along the rivers decrease while the water demand is increase. The study indicates the necessary to study quantitatively some recommended solutions in the study area particularly and in coastal region generally in Vietnam to ensure water demand for irrigation and other purposes in the context of climate change and sea level rise in the future.

• Journal of Fisheries and Marine Sciences Education
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• v.25 no.6
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• pp.1408-1418
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• 2013

To investigate the quality properties of functional anchovy fish sauce added with raw sea tangle, 2%, 5%, and 10% (w/w) of sea tangle was added to 25% (w/w) salted anchovy and then fermented at $20^{\circ}C$. During fermentation period, the amino nitrogen contents were increased at all groups and the highest contents were at 450 days of fermentation with $11.99{\pm}0.08$, $12.51{\pm}0.08$, and $11.95{\pm}0.08mg/mL$ at 2%, 5%, and 10% addition of raw sea tangle, respectively. After later, the contents were keeping at a similar level. VBN contents were continuously increased until 270 days of fermentation with $208.10{\pm}3.50$, $210.00{\pm}4.10$, $215.15{\pm}1.50mg/100ml$ at 2%, 5%, 10% addition of raw sea tangle, respectively. Alginic acid recovery was gradually increased in fermentation duration, showed the highest concentration at 540 days of fermentation with 67.00, 67.25, 67.90% at 2%, 5% and 10% addition of raw sea tangle, respectively. Dietary fiber recovery was rapidly increased at the beginning of fermentation and then decreased slowly as the fermentation is progressed. The highest recovery was at 30 days with 18.7, 18.6, and 17.9%, and the lowest was at 360 days with 8.7 and 11.1% at 2 and 10% addition of raw sea tangle, respectively, and 450 days with 11.4% at 5% sea tangle. The lowest fucoidan contents were exhibited at 30 days of fermentation with 0.07% at both of 2% and 5% addition, and 90 days with 0.10% at 10% addtion of sea tangle. The highest fucoidan contents were 270 days showing 0.24, 0.25, and 0.23% at 2, 5, and 10% addition, respectively. All groups adding different sea tangle concentration were not significantly different at all properties. However, the newly developed products were sufficient to the standard guideline of Korea Food Drug Adminstration. The best processing process of functional anchovy fish sauce in addition with raw sea tangle is 2% addition of raw sea tangle and fermented more than 450 days. The results obtained in this study indicated that the fish sauce added with sea tangle is superior in taste, functions to traditional fish sauce and could be competitive fishery fermented food.

• Atmosphere
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• v.17 no.1
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• pp.45-53
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• 2007

In order to investigate the impacts of heat wave on human health, cluster analysis of meteorological elements (e.g., temperature, dewpoint, sea level pressure, visibility, cloud amount, and wind components) for identifying offensive synoptic air masses is employed. Meteorological data at Seoul during the past 30 years are used. The daily death data at Seoul are also employed. Occurrence frequency of heat waves which is defined by daily maximum temperature greater than the threshold temperature (i.e., $31.2^{\circ}C$) was analyzed. The result shows that the frequency and duration of heat waves at Seoul are increasing during the past 30 years. In addition, the increasing trend of the frequency and duration clearly appears in late spring and early autumn as well as summer. Factor analysis shows that 65.1% of the total variance can be explained by 4 components which are linearly independent. Eight clusters (or synoptic air masses) were classified and found to be optimal for representing the summertime air masses at Seoul, Korea. The results exhibit that cluster-mean values of meteorological variables of an offensive air mass (or cluster) are closely correlated with the observed and standardized deaths.

• Korean Journal of Plant Resources
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• v.19 no.6
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• pp.680-686
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• 2006

This experiment was conducted on wild vegetables; Gondalbi (Cirsium setidens), Deoduck (Codonopsis lanceolata Trautv.), and Jandae (Adenophora triphylla var. Joponica Hara) seed to study whether priming with deep sea water results in enhancement of seed germination and identify the optimum concentration of the priming solution, and duration of priming. Seeds were primed with 5 various concentrations (5%, 10%, 15%, 20% and 30%) of deep sea water (DSW) in 12 hours, 24 hours, and 48 hours at $24^{\circ}C$. Since Jandae had seed dormancy, it was kept for four weeks in refrigerator at $2^{\circ}C$ after priming treatment. In Deoduck, 5 percentage DSW priming significantly improved the early germination percentage, radicle length, and plumule emergence percentage. Among the priming period of treatments, 24 hours priming showed better performance in this treatment whereas, in Jandae, 12 hours priming with 10 percentages DSW significantly improved the germination percentage and germination rate. This treatment had increased the final germination percentage by 54%, 15% and 40% compared with control, plain water and $KNO_3$ priming respectively. But in Gondalbi, priming did not improve the germination of seed. However, among the priming treatments, 12 hours priming with 3% $KNO_3$ and 20% DSW gave better performance. In both the wild vegetables; Deoduck and Jandae, priming in deep sea water had improved the germination percentage and germination rate as compare to plain water, $KNO_3$, and without priming treatment. Hence the best seed priming treatment on Deoduck and Jandae are 24 hours with 5% DSW and 12 hours with 10% DSW respectively.

• Proceedings of the Korea Water Resources Association Conference
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• 2002.05b
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• pp.1195-1204
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• 2002

The impacts of El Nino Southern Oscillation (ENSO) phenomenon on climate are widespread and extend far beyond the tropical Pacific. The phenomenon can be characterized by Southern Oscillation Index (SOI) which is derived from values of the monthly mean sea level pressure barometric difference between Tahiti and Darwin, Australia. Its best-known extreme is the El Nino event. In this study, general statistical characteristics of SOI and the data from which it is derived (i.e. mean sea level pressure data at Tahiti and Darwin) are presented as guidance when using SOI far other analyses. The characteristics include the availability of the barometric pressure data, statistics of monthly pressure data, correlation of SO intensity, frequency analysis of SOI by magnitude and by month (January-December), duration properties of SOI by run analysis.

• International Journal of Industrial Entomology and Biomaterials
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• v.8 no.1
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• pp.27-32
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• 2004

With an objective of evolving quantitatively and qualitatively superior bivolitine silkworm hybrid of Bombyxmori L. for tropics with shorter larval duration without compromising on productivity traits, a breeding programme was initiated at this institute during 1997 by utilizing breeding resource material from the institutes Germplasm collection. The breed SD7 is characterized with plain larvae spinning white oval cocoons and SD12 is characterized by sex-limited larval markings spinning white dumb-bell cocoons. After fixation, these breeds along with other newly evolved breeds were subjected for hybrid evaluation in the laboratory. Based on the hybrid studies, the hybrid SD7${\times}$SD12 was selected and evaluated for one year comprising three major sea- sons (6 trials) of tropics viz., Pre-monsoon (characterized by high temperature, low humidity and without any rain fall), Monsoon (characterized by moderate temperature, heavy rain fall with high humidity) and post-monsoon season (characterized by low temperature and low humidity with frequent rain fall) to know the fluctuations in the larval duration. The evaluation studies indicated that the hybrid is having shorter larval duration with productive merits. The hybrid SD7${\times}$SD12 recorded survival percent of 92.74, shell weight of 46.7 cg, shell ratio % of 24.0 and filament length of 1,200 meters with a shorter larval duration of 24 hrs; when compared to productive hybrid CSR2${\times}$CSR5(control). The breeding methodologies and hybrids usefulness for tropics were discussed.

• The Korean Journal of Malacology
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• v.27 no.2
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• pp.99-105
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• 2011

This study was conducted to compare the species composition of sessile organisms on the artificial substrates of PVC submerged at different time intervals and duration in Jangmok Bay, Geoje Island, southern coast of Korea. Three PVC plates were submerged at one month interval from March to October and retrieved in November, 2007. A mussel, Mytilus galloprovincialis exclusively occupied the artificial substrates submerged from March to April and occurred as a dominant species to July. An ascidian, Styela plicata occurred as a dominant sessile species from May to August. Balanus amphtrite, Bugula sp., and hydrozoans occurred as dominant species on the plates submerged from July to September. There was a mis-match between the peak time of settlement and dominance of sessile organisms due to the interspecies competitions when the PVC plates were retrieved in November. There was no clear relationship between submerged duration and the abundance of sessile organisms due to the different settlement period. M. galloprovincialis seemed to be a strong competitor which could exclude the previous recruiters of macroalgae by overgrowth and occupy the substrate surface and maintain its high population density by preventing the settlement of other species until late autumn. These results suggested that the composition of sessile organisms in vacant hard substrates could be determined by the combined effects of supply-timing of larvae and post-settlement competitions.

• Journal of Environmental Science International
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• v.18 no.10
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• pp.1163-1170
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• 2009

The clam, Gomphina melanaegis, which is commonly called the sandy beach clam because of its habitat, is a valuable organism in the sandy coast of East Sea, Korea. It is frequently observed in large populations between 0.5 and 5 meters. We have released 50,000 seedling, ranging from the diameter of approximately 3 mm, 2007, and 1,000,000 seedling, ranging from the diameter of approximately 0.2 mm, plus 100,000 adult individuals, ranging from the shell length of approximately 20~40 mm, 2008 at Jinha beach. The spawning period of G. melanaegis, was from June to August, and the main spawning occurred in July. This investigation was carried out to elucidate population distribution on the stocking area of sandy beach clam, G. melanaegis. The relationship between shell length and ring radius in each ring was investigated as a regression line. The relationship between the shell length and shell height of released young clam was SH=1.0105SL-4.7764 ($R^2=0.7905$). The relationship between the shell length and total weight of released young clam was $TW=0.0013SL^{2.3966}$($R^2=0.71$). It draws a deduction that the ring of this clam was produced once a year during the duration between June and August.