• Journal of the korean society of oceanography
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• v.34 no.1
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• pp.49-57
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• 1999

A red tide organism, Amphidinium carterae was incubated under different iron/chelator and nitrate concentrations to investigate the factors controlling the growth. The chelation capacity played a critical role in regulating the nitrate reductase (NR) activity and in vivo fluorescence of this organism. However, there was a significant difference between the NR activity and in vivo fluorescence in response to trace metals and chelator treatments. In vivo fluorescence was the highest in FeEDTA 10 ${\mu}$M treatments and the lowest in DTPA 10 ${\mu}$M treatments. This indicates that the availability of the trace metal is important in regulating the in vivo fluorescence of this photosynthetic microalgae In contrast, NR activity showed the highest values in trace metal enriched treatments, and trace metal + DTPA treatments showed fairly high NR activities. This suggests that DTPA treatment did not hinder the NR activity as much as it did in vivo fluorescence. In vivo fluorescence and NR activity increased with nitrate concentration of up to 50 ${\mu}$M and remained relatively constant or the rate of increase decreased above that concentration, indicating that initial nitrate concentration of higher than a certain level would not accelerate the growth of A. carterae. Further investigation is needed to elucidate the reason for the difference in timing sequence between the NR and in vivo fluorescence in response to different metal treatments and chelation capacity.

• Journal of Arbitration Studies
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• v.15 no.2
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• pp.61-91
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• 2005

It is well recognized that the availability of prompt, effective and economical means of dispute resolution is an important element in the orderly growth and encouragement of international trade and investment. Increasingly, ADR(Alternative Dispute Resolution) including arbitration and mediation, instead of litigation in national courts, has become the preferred means of resolving private international commercial disputes. Under the situation, efforts for settlement of trade and investment disputes by ADR have been made between Korea and China through trade and investment agreements and arbitration agreement. Judging from the importance of economic exchange between Korea and Qingdao including Shandong Province, The Korean Commercial Arbitration Board(KCAB) and The Qingdao Arbitration Commission(QAC) should strengthen mutual cooperation to develop efficient methods of resolving commercial disputes arising between the two countries and to assist parties in solving those disputes through conclusion of arbitral agreement. Recently, efforts for conclusion of a Korea-China-Japan Free Trade Agreement(FTA) received strong support at Korea-Japan and Korea-China Summit Meeting held on June and July, 2003 respectively. If the conclusion of FTA among the three countries would be realized, it would promote regional trade and investment, contributing to economic growth in the Northeast Asian region. Under the circumstances, the key arbitral institutions including KCAB and QAC should consider to take the initiative in setting up tentatively called ${\ulcorner}$Joint Arbitration Center for Northeast Asia${\lrcorner}$ for which the CAMCA of NAFTA will be the good example.

• Korean Journal of Environmental Agriculture
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• v.22 no.3
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• pp.197-202
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• 2003

Phosphorus is one of the major plant growth limiting nutrients, despite being abundant in soils in both inorganic and organic forms. Phosphobioinoculants in the form of microorganisms can help in increasing the availability of accumulated phosphates for plant growth by solubilization. Penicillium oxalicum CBPSTsa, isolated from paddy rhizosphere, was studied for its phosphate solubilization. The influence of various carbon sources like glucose, sucrose, mannitol and sorbitol and nitrogen sources like arginine, sodium nitrate, potassium nitrate, ammonium chloride and ammonium sulphate were evaluated using liquid media with tricalcium phosphate (Ca-P), ferric phosphate (Fe-P) and aluminium phosphate (Al-P). Maximum soluble phosphate of 824 mg/L was found in the amendment of sucrose-sodium nitrate from 5 g/L of Ca-P. Mannitol, sorbitol, and ariginine were poor in phosphate solubilization. While sucrose was better carbon source in solubilization of Ca-P and Al-P, glucose fared better in solubilization of Fe-P. Though all the nitrogen sources enhanced P solubilization, nitrates were better than ammonium In the amendments of ammonium chloride and ammonium sulphate, higher uptake of available phosphates by the fungus was found, and this resulted in depletion of available P in Fe-P amendment Phosphate solubilization was accompanied by acidification of the media, and the highest pH decrease was observed in glucose amendment Among the nitrogen sources, ammonium chloride favored greater pH decrease.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.8
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• pp.1089-1101
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• 2013

Effects of varied dietary energy densities on immune response and performance of Muzzafarnagari lambs were ascertained in a 180-d study. Animals (n = 24), in three groups, were fed diets providing 100% (100E), 80% (80E) or 70% (70E) of their metabolizable energy requirement. Mean nutrient digestibilities varied significantly among treatments. Nitrogen intake was lower (p<0.01) in the 70E. Nitrogen retention, was reduced (p<0.001) in 80E and 70E vs 100E. The average daily gain (p<0.001) was $47.01{\pm}4.23$, $13.54{\pm}1.72$ and $-16.67{\pm}8.24$ g for 100E, 80E and 70E, respectively. Hemoglobin concentration, haematocrit, total and differential leukocyte counts were lower (p<0.001) for 80E and 70E than for 100E with a similar trend (p<0.05) for serum glucose and total protein. Serum cortisol was reduced (p<0.001) with decreased energy availability. Antibody titre to Brucella abortus S19 showed an initial reduction in 80E and 70E vs 100E. Delayed-type hypersensitivity response was lower (p<0.001) in 80E and 70E vs 100E, accompanying a lower (p<0.001) nitric oxide production by the peripheral lymphocytes. It is concluded that the reduced dietary energy density significantly affects the growth performance and immune response of lambs.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.3
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• pp.316-320
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• 2001

Sixteen growing crossbred Anglo-Nubian goats, 10-12 months old, pre-experimental average body weights of $18.3{\pm}0.28kg$ were randomly allotted to four diets to investigate the efficiency of utilisation of diets containing increasing levels of desiccated coconut waste meal (DCWM) in the tropical environment of Samoa, South Pacific region. The four diets were designated as 1, 2, 3 and 4. Diet 1 that has no DCWM served as the control, while diets 2, 3 and contained different levels of DCWM. Voluntary concentrate intake, growth rate, feed efficiency and nutrient digestibility coefficients were measured. Gross energy (GE) and organic matter (OM) values of the diets increased linearly with increase in the levels of DCWM in the diets. Voluntary concentrate intake decreased with increasing proportion of DCWM in the diets. Forage intake increased with increase in the levels of DCWM diets offered to the growing goats. Total voluntary feed intakes were statistical significant (p<0.05) and the goats on diet 4 had the least intake followed by those on diet 3. Goats an diets 1 and 2 were different in total feed intake but not at a significant level (p>0.05). Feed efficiency (FE) followed the trend of voluntary concentrate intake and daily live weight gains. Dry matter digestibility (DMD) was significantly different (p<0.05) among the goats offered the different diets. DMD improved with increasing levels of DCWM. The goats accepted all, the diets that were compounded with the different levels of dried DCWM and this seems to suggest that DCWM have no deleterious effects. However, the best level at which dried DCWM could replace brewers dried grains in the diets of growing goats is at 38.5% (diet II). Based on voluntary feed intake, live-weight gain and apparent nutrient digestibility coefficients of the goats it could be concluded that DCWM based diets merits further attention as a locally available feed source in ruminants nutrition in the Pacific Island countries where feed availability is seasonal.

• Journal of The Korean Society of Agricultural Engineers
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• v.51 no.5
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• pp.1-8
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• 2009

Photobioreactor (PBR) that houses and cultivates microalgae providing a suitable environment for its growth, such as light, nutrients, CO2, heat, etc. is now getting more popular in the last decade. Among the many types of PBRs, the bubble column type is very attractive because of its simple construction and easy operation. However, despite the availability of these PBRs, only a few of them can be practically used for mass production. Many limitations still holdback their use especially during their scale-up. To enlarge the culture volume and productivity while supplying optimum environmental conditions, various PBR structures and process control are needed to be investigated. In this study, computational fluid dynamics (CFD) was economically used to design a bubble-column type PBR taking the place of field experiments. CFD is a promising technique which can simulate the growth and production of microalgae in the PBR. To study bubble column PBR with CFD, the most important factor is the possibility of realizing bubble. In this study, multi-phase models which are generally used to realize bubbles were compared by theoretical approaches and comparing in a 2D simulation. As a result, the VOF (volume of fluid) model was found to be the most effective model to realize the bubbles shape as well as the flow inside PBR which may be induced by bubble injection. Considering the accuracy and economical efficiency, 0.005 second time step size was chosen for 2.5 mm mesh size. These results will be used as criteria for scale-up in the PBR simulation.

• Asian Journal of Turfgrass Science
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• v.15 no.1
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• pp.15-20
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• 2001

Two types of annual bluegrass have been reported, and those consist of annual type (Poa annua ssp. annua) and perennial type (Poa annua ssp. reptans). As a weed, annual bluegrasses are commonly found in putting greens and fairways in many golf courses. Due to its strong competitiveness such as tremendous seed reproduction rate a year, prostrate growth habit, and no herbicide availability, annual bluegrasses have been considered as one of the most hard-to-control weeds in turf management systems. A growth chamber study was conducted to determine seed dormancy and to understand seed germination characteristics of annual bluegrass (Poa annua ssp. annua). Freshly harvested seeds showed 80 and 55% germination at 30 and $35^{\circ}C$, respectively, indicating that the optimum temperature of annual bluegrass is $30^{\circ}C$. However, the seed germination occurred only under light condition at any given temperature. This result demonstrated that light is prerequisite for the seed germination, and no primary dormancy of annual bluegrass seed exists. Secondary seed dormancy induced by unfavorable temperatures and dark condition was broken through 4 to 6 wk-storage at $4^{\circ}C$ with moisture, and the stored seeds germinated at $20^{\circ}C$ even under the dark. In red and far-red light trial, fresh seeds resulted in 40% germination under red while no seed germination occurred under far-red light condition, indicating that phytochrome Pr and Pfr could be related to annual bluegrass seed germination. When the far-red light replaced the red the germination was recovered, but this reversibility did not reach to the germination level under the red light only. This result implied that other lights than red and far-red would play an important role on seed germination of annual bluegrass.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.30 no.4
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• pp.143-149
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• 2020

Calcium phosphates recognized as important bio-materials have been successfully synthesized by simple precipitation using waste abalone shells, which are rich mineral sources of calcium. Calcium hydroxide (Ca(OH)₂) originated from abalone shells was used as calcium source (precursor) for the preparation. Synthesis of calcium phosphates was performed by reacting calcium hydroxide with phosphoric acid (H₃PO₄) in aqueous solution. The initial precursor Ca/P ratios were adjusted to 1.50, 1.59 and 1.67, and the effect of the composition and the heat treatment on the synthesized powders and sintered bodies was investigated. The phases of the sintered ceramics prepared at 1150℃ were hydroxyapatite (HAp), β-tricalcium phosphate (β-TCP), and biphasic phosphate (HAp with β-TCP)), which were determined by the initial precursor Ca/P ratios. The results demonstrate the possibility for the synthesis of high value-added calcium phosphates from economical starting materials with low cost and high availability.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.7 no.3
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• pp.35-47
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• 2004

In order to study changes in vegetation pursuant to rooftop revegetation plantation methods, plantation methods for rooftop revegetation were divided into two types through an analysis of recent trends. Then, Planted plants and invasive plants on sites where the planting methods were introduced were monitored. Planting methods were divided into mono-layer meadow cover type and multi-layer planting cover type. They showed some differences in terms of the availability of wetland, the structure of vegetation layers, the planted species, and the material of mulching. According to the results of monitoring the two sample sites for different plantation methods, the number of invasive plants was higher in multi-layer planting cover type and the ratio of naturalized plants was higher by 30% in average in mono-layer meadow cover type. The main reason for such a result is that the natural soil used in the multi-layer planting cover type likely contained some seeds. Moreover, it's harder for invasive plant seeds to germinate in volcanic rocks than in natural soil. Also, it is attributable to wetlands available in multi-layer planting cover type and diverse living environments created by multi-layer planting. The reason of the ratio of naturalized plants being higher by at least 10% in mono-layer meadow cover type is the character of naturalized plants being stronger in unfavorable conditions than nature plants are. Accordingly, the germination rate in the volcanic rock mulching has likely contributed in raising the introduction and germination of naturalized plants. The results showed that multi-layer planting cover type using wetland creation and nature soil can increase the number of invasive plants and lower the ratio of naturalized plants. However, since seeds contained in the natural soil can affect the growth of planted plants, this needs to be clarified, It was judged that mono-layer meadow cover type may affect more greatly on the germination and growth of invasive plants than on those of planted plants, Its potential adoption in highly urbanized areas was examined. By complementing with the mutual benefits of each plantation method, it appeared possible to shift to a rooftop revegetation system suitable to the site.

• Korean Journal of Remote Sensing
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• v.33 no.6_1
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• pp.993-1001
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• 2017

Drought is a worldwide natural disaster with extensively adverse impacts on natural ecosystems, agricultural products, social communities and regional economy. Various global satellite observations, including SMAP soil moisture, GRACE terrestrial water storage, Terra and Aqua vegetation productivity, evapotranspiration, and satellite precipitation measures are currently used to characterize seasonal timing and inter-annual variations of regional water supply pattern, vegetation growth, drought events, and its associated influence ecosystems and human society. We suggest the satellite monitoring system development to quantify meteorological, eco-hydrological, and socio-ecological factors related to drought events, and characterize spatial and temporal drought patterns in Korea. The combination of these complementary remote sensing observations(visible to microwave bands) provide an effective means for evaluating regional variations in the timing, frequency, and duration of drought, and availability of water supply influencing vegetation and crop growth. This integrated drought monitoring could help national capacity to deal with natural disasters.