• The Journal of Fisheries Business Administration
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• v.39 no.2
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• pp.25-39
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• 2008

The Korean government is in the establishment process of plan for managing fishing effort by setting up the maximum fishing gear usage per fishery type for the recovery of fishery resources, for the settlement of disputes between fishery sectors over fishing gears, and for the stability of fishing business condition. Especially in the setting up of the maximum fishing gear usage, economic standards as well as biological standards are being considered as a significant factor to promote the sustainable and economically viable development of fisheries. This study is, thus, to analyze the optimal economic fishing gear usage ($E_{MEY}$) as the most economically efficient one for the coastal snow crab gillnet fishery, one of the most controversial sectors in establishing the maximum fishing gear usage. The data of logbooks per trip were used for concentrating on the estimation of $E_{MEY}$ per trip because it was considered there were limitations of data available for analyses. As a finding drawn from the analyses, the optimal economic trap usage ($E_{MEY}$) of coastal snow crab gillnet vessels per trip has to be decreased by about 13%. That is, reducing the trip gillnet usage up to the level of $E_{MEY}$ can lead to the reduction of trip fishing costs, thereby resulting in the increased trip profits.

• Journal of Microbiology and Biotechnology
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• v.25 no.9
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• pp.1547-1554
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• 2015

The potential of microalgae biofuel has not been realized because of the low productivity and high costs associated with the current cultivation systems. In this study, a new low-cost and transparent attachment material was tested for cultivation of a filamentous algal strain, Stigeoclonium sp., isolated from wastewater. Initially, the different materials tested for Stigeoclonium cultivation in untreated wastewater were nylon mesh, polyethylene mesh, polypropylene bundle (PB), polycarbonate plate, and viscose rayon. Among the materials tested, PB led to a firm attachment, high biomass (53.22 g/m², dry cell weight), and total lipid yield (5.8 g/m²) with no perceivable change in FAME profile. The Stigeoclonium-dominated biofilm consisted of bacteria and extracellular polysaccharide, which helped in biofilm formation and for effective wastewater treatment (viz., removal efficiency of total nitrogen and total phosphorus corresponded to ~38% and ~90%, respectively). PB also demonstrated high yields under multilayered cultivation in a single reactor treating wastewater. Hence, this system has several advantages over traditional suspended and attached systems, with possibility of increasing areal productivity three times using Stigeoclonium sp. Therefore, multilayered attached growth algal cultivation systems seem to be the future cultivation model for large-scale biodiesel production and wastewater treatment.

• Journal of the Korean Society of Groundwater Environment
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• v.1 no.1
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• pp.33-50
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• 1994

The Hydrogeologic data of 455 water wells comprising geologic log and aquifer test were analyzed to determine hydrogeologic characteristics of the Cheju island. The groundwater. of the Cheju island is occurred in unconsolidated pyroclastic deposits and crinker interbedded in highly jointed basaltic and andesic rocks as high level, basal and parabasal types under unconfined condition. The average transmissivity and specific yield of the aquifer are at about 29,300㎡/day and 0.12 respectively, The total storage of groundwater is estimated about 44 billion cubic meters. Average annual precipitation is about 3,390 million ㎥ among which average recharge is estimated for 1,494 million ㎥ being equivalent 44.1% of total annual precipitation with 638 million ㎥ of runoff and 1,256 million ㎥ of evapotranspiration. Based on groundwater budget analysis, the sustainable yield is about 620 million ㎥(41% of annual recharge)and rest is discharging into the sea. The geologic logs of recently drilled thermal water wells indicate that very low-permeable marine sediments(Sehwa-ri formation) composed of loosely cemented sandy silt derived from mainly volcanic ashes at the 1st stage volcanic activity of the area is situated at the 120${\pm}$68m below sea level. Another low-permeable sedimentary rock called Seogipo-formation which is deemed younger than the former marine sediment is occured at the area covering north-west and western part of the Cheju island at the ${\pm}$70m below sea level. If these impermeable beds art distributed as a basal formation of fresh water zone of the Cheju island, the most of groundwater in the Cheju island will be para-basal type. These formations will be one of the most important hydrogeologic boundary and groundwater occurences in the area.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.59-59
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• 2017

Rice (Oryza sativa L.) is the most important crop and its yield must be improved to feed the increasing global population. Recently developed high-yielding varieties with extra-large sink capacity often have a problem in unstable grain-filling. Therefore, understanding limiting factors for improving grain-filling and controlling them are essential for further improvement of rice grain yield. However, since grain-filling rate was determined by complex sink-source balance, the ability of grain-filling was very difficult to evaluate. Source ability for 'grain' was not only determined by the ability of carbon assimilation in leaves, but also that of carbon translocation from leaves to panicles. Sink strength was determined by the complex carbon metabolism from sucrose degradation to starch synthesis. Hence, to evaluate the grain-filling ability and determine its regulatory steps, the whole picture of carbon flow from photosynthesis at leaves to starch synthesis at grains must be revealed in a metabolite level. In this study, the yield and grain growth rate of three high-yielding varieties, which show high sink capacity commonly, were compared. Momiroman showed lower grain filling rate and slower grain growth rate than the other varieties, Hokuriku 193 and Tequing. To clarify the limiting point in the carbon flow of Momiroman, $CO_2$ labeled by stable isotope ($^{13}C$) was fed to three varieties during ripening period. The ratio of $^{13}C$ left in the stem was higher in Momiroman 24 hours after feeding, suggesting inefficient carbon translocation of Momiroman. More interestingly, $^{13}C$ translocation from soluble fraction to insoluble one in the grain seemed to be slower in Momiroman. To get the further insight in a metabolite level, we are now trying the $^{13}C$ labeling metabolome analysis in the developing grains.

• Korean Journal of Soil Science and Fertilizer
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• v.47 no.3
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• pp.165-171
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• 2014

Assessment of sustainable production on a cropland can help to determine the most proper management practices. In this study, we evaluated the sustainable production on paddy field treated with green manure crops using sustainability index which based on nutrient index, microbiological index, and crop index related to nutrient-supplying capacity. Especially choosing appropriate indicators from a minimum data set (MDS) were used the principal components analysis (SI-2) as well as expert opinion (SI-1) usually used in sustainability index. Six treatments including the two tillage treatments and two green manure crops were investigated as follows; (i) moldrotary + rotary tillage without green manure crop (Con), with (ii) hairy vetch (Con-HV), and (iii) hairy vetch + green barely (Con-HV+GB), (iv) rotary tillage without green manure crop (Rot), with (ii) hairy vetch (Rot-HV), and (iii) hairy vetch + green barly (Rot-HV+GB). Con-HV and Rot-HV in SI-1 were maintained sustainability while Rot-HV and Rot-HV+GB in SI-2. Especially, treatments (Con and Rot) without green manure crops were more unsustainable than with green manure crops because of the low value of microbiological and crop index than with green manure crops. Meanwhile, sustainability indices and grain yield had the high correlation values ($R^2=0.756$ and 0.928 in SI-1 and SI-2, respectively). These results meant that application of green manure crops such as hairy vetch could improve both yield and soil quality in paddy.

• Food Science of Animal Resources
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• v.37 no.6
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• pp.955-961
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• 2017

Edible insects are attracting growing interest as a sustainable source of protein for addition to processed meat and dairy products. The current study investigated the optimal method for protein extraction from mealworm larvae (Tenebrio molitor), cricket adults (Gryllus bimaculatus), and silkworm pupae (Bombyx mori), for use in further applications. After defatting with n-hexane for up to 48 h, sonication was applied for 1-20 min and the protein yield was measured. All samples showed a total residual fat percentage below 1.36%, and a 35% to 94% improvement in protein yield (%). In conclusion, defatting with n-hexane combined with sonication improves the protein yield from insect samples.

• Food Science and Industry
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• v.51 no.2
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• pp.114-126
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• 2018

The production of high quality oil to meet new standard needs a 'next generation' innovative oil refining tool in paradigm shift. 'Nanoneutralization' using controlled hydrodynamic cavitation-assisted Nanoreactor is successfully being introduced and commercialized into edible oil industry and it plays a key driver for sustainable development of food processing. This emerging technology using bubble dynamics as a consequence of Bernoulli's principle by hydrodynamic cavitation in Venturi-designed multi-flow through cell is radically changing the conventionally chemical-oriented neutralization. Nanoneutralization derived by the creation of nanometer-sized bubbles formed through scientifically structured geometric channels under high pressure has been proven to improve mass transfer and reaction rate so substantially reduce the chemicals required for refined vegetable oil and to increase oil yield while even improving oil quality. More researches on science behind this revolutionary technology will help usto better understand the principle and process hence makes its potential applications expandable in extraction, refining and modification of fats and oils processing.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.45 no.5
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• pp.493-498
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• 2012

We derived biological reference points for Pacific cod Gadus macrocephalus in southeastern Korean waters by applying a yield-per-recruit analysis based on a daily simulation that adopted size-dependent fecundity, growth, and natural mortality functions. This showed that the yield per recruit of Pacific cod can be maximized at an instantaneous rate of fishing mortality (F)=0.37 $yr^{-1}$ under the current regulations, where the minimum catch size ($L_c$)=30 cm in total length (TL). The maximum economic yield was estimated to be attained at $L_c$=35-45 cm TL, if F>1 $yr^{-1}$ but at $L_c$=35-40 cm TL, if F<1 $yr^{-1}$. Despite great uncertainty in the stock assessment, to develop fisheries management plans for the sustainable exploitation of Pacific cod in southeastern Korean waters, it is necessary to estimate F using capture-recapture or other expedient methods.

• Journal of Forest and Environmental Science
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• v.30 no.2
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• pp.189-200
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• 2014

The tropical wet evergreen, tropical semi evergreen and moist deciduous forest types are projected to be impacted by climate change. In the Western Ghats region, a biodiversity hotspot, evergreen forests including semi evergreen account for 30% of the forest area and according to climate change impact model projections, nearly a third of these forest types are likely to undergo vegetation type change. Similarly, tropical moist deciduous forests which account for about 28% of the forest area are likely to experience change in about 20% of the area. Thus climate change could adversely impact forest biodiversity and product flow to the forest dependent households and communities in Uttara Kannada district of the Western Ghats. This study analyses the distribution of non-timber forest product yielding tree species through a network of twelve 1-ha permanent plots established in the district. Further, the extent of dependence of communities on forests is ascertained through questionnaire surveys. On an average 21% and 28% of the tree species in evergreen and deciduous forest types, respectively are, non-timber forest product yielding tree species, indicating potential high levels of supply of products to communities. Community dependence on non-timber forest products is significant, and it contributes to Rs. 1199 and Rs. 3561/household in the evergreen and deciduous zones, respectively. Given that the bulk of the forest grids in Uttara Kannada district are projected to undergo change, bulk of the species which provide multiple forest products are projected to experience die back and even mortality. Incorporation of climate change projections and impacts in forest planning and management is necessary to enable forest ecosystems to enhance resilience.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.54 no.2
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• pp.124-137
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• 2018

Due to the decrease in coastal productivity and deterioration in the quality of ecosystem which result from the excessive overfishing of fisheries resources and the environmental pollution, fisheries resources in the Korean waters hit the dangerous level in respect of quantity and quality. In order to manage sustainable and effective fisheries resources, it is necessary to suggest the potential yield (PY) for clarifying available fisheries resources in the Korean waters. So far, however, there have been few studies on the estimation methods for PY in Korea. In addition, there have been no studies on the comparative analysis of the estimation methods and the substantial estimation methods for PY targeted for large marine ecosystem (LME) For the reasonable management of fisheries resources, it is necessary to conduct a comprehensive study on the estimation methods for the PY which combines population dynamics and ecosystem dynamics. To reflect the research need, this study conducts a comparative analysis of estimation methods for the PY in the Korean waters of the East Sea to understand the advantages and disadvantages of each method, and suggests the estimation method which considered both population dynamics and ecosystem dynamics to supplement shortcomings of each method. In this study, the maximum entropy (ME) model of the holistic production method (HPM) is considered to be the most reasonable estimation method due to the high reliability of the estimated parameters. The results of this study are expected to be used as significant basic data to provide indicators and reference points for sustainable and reasonable management of fisheries resources.