• Journal of Aquaculture
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• v.20 no.2
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• pp.90-95
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• 2007

Artificially-produced juvenile black sea bream, Acanthopagrus schlegeli (total length $10.4{\pm}1.1\;cm$, body weight $18.7{\pm}3.4\;g$) were released into the Gamak Bay in Korea. And their initial feeding habits and body compositions were compared with those of cultured fish (CUL) for a period of one month after release. The released black sea bream commenced feeding on the 1st day after release, and predation rate was more than 80% during the sampling period. The stomach content of fish was composed of mainly fishing bait and krill in fish sampled on 15th days after release; however, its content changed to the natural organisms such as algae and small crustaceans when the fish was sampled on 20th days after release. Crude lipid content of carcass of fish in the sampling station A (SA) were lower than that of fish in the initial, sampling station B (SB) and CUL for the 5th and 10th days after release. Carcass n-3 HUFA composition, total amino acid and essential amino acid contents of released fish showed high trend compared to that of cultured fish in 30th days after release. The released fish have the ability to adjust their feeding habits and biochemical metabolism to the natural environment within a short period even though they showed preference to artificial feed in the early days after release.

• Korean Journal of Ecology and Environment
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• v.33 no.4 s.92
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• pp.342-349
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• 2000

This paper demonstrates the influence of intensity of the monsoon on morpho-hydrological fluctuations in Taechung Reservoir during 1993${\sim}$1994. During the study, hydrological variables including rainfall, inflow, and discharge volume showed distinct contrast between 1993 and 1994. Interannaul differences in rainfall occurred during the monsoon in July${\sim}$August monsoon and influenced inflow, discharge, and water residence time (WRT). Total inflow in 1993 was four times greater than that of 1994, and summer inflow in 1993 was 8 times greater than summer 1994. Annual Mean WRT was 93.2 d in 1993 vs. 158.6 d in 1994 and the largest differences occurred between monsoons of 1993 and 1994. Morphometric variables reflected the interannual contrasts of hydrology, so that in 1993 surface area, total volume, shoreline development, and mean depth increased consistently from premonsoon to postmonsoon and over this same period in 1994 they decreased. This outcome indicates that the area of shallow littoral zones in 1993 was greater than in 1994. Also, the drainage area to surface area (D/L) at 80 m MSL was 60.7 which was much greater than values in Soyang and Andong reservoirs and natural lakes world-wide. The morpho-hydrodynamic conditions seemed to influence in-reservoir nutrient concentration which is one of the most important factors regulating the eutrophication processes. I believe, under the maximum hydrodynamic fluctuations in Korean waterbodies during the monsoon, applications of mass balance models to man-made lakes for assessments of external loading should be considered because the models can be used under the seasonally stable inflow and water residence time.

• Korean Journal of Environmental Biology
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• v.18 no.3
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• pp.323-330
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• 2000

Early life history and spawning for Odontobutis interrupta were observed in the laboratory during May-August 1999 with a condition of natural habitats in the field. Optimal water temperature for spawning was between 17.5 and 22.$0^{\circ}C$ and appropriate water depth and current velocity in the natural habitat ranged 0.3-0.6 m and 0.1-0.3 m/sec, respectively. Ovary maturation index peaked at about 100mm in the total length and their values gradually decreased after the size. Male fishes showed a territory and courtship behavior to adult females and the males frequently pushed upper-ventral part of females for egg releases. After females spawned, the males guarded the egg masses and supplied dissolved oxygen using pectoral fins. According to observation of egg development in the laboratory, blastodisc formed in 1hr 17 min after the fertilization, cleavaging at 36-minute interval regularly. Blastulation occurred in 7 hr 12 min after the fertilization, with gastrulation after 11 hr 11 mins and formation of york plug after 32 hr 48 min. Embryo was formed in 33 hr 45 min after fertilization and optic vesicles appeared in 47 hr 27 mins when 30-31 somites were formed. Cardiac primordium was formed in 65 hr 15mins and its beat averaged 44- 48 time/min. Pectoral fins were formed in 138 hr 40 min, air-bladder and black vesicles were observed in lower portion of young fish. Embryo hatched from she-11 membrane after about 10 days and juvenile was 5.8$\pm$0.2mm in total length 3.0$\pm$0.5mg in weight.

• The Journal of the Korea Contents Association
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• v.19 no.12
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• pp.113-120
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• 2019

South Korea is an aging society with 10.9 percent of its population over 65 years of age, and the aging population naturally leads to a surge in elderly care costs. Compared to general hospitals and other hospitals that have systematic management strategies in an environment of intensifying hospital competition, the design and management strategies of nursing hospitals are insufficient due to the hospital's characteristics of long-term hospital admission and treatment. In this study, We conducted a symbol mark color and form analysis of nursing hospitals to establish a design strategy to meet the increasing demand on nursing hospitals. The subjects of the study were 131 hospitals that received the first grade of nursing hospitals in Korea, and each symbol mark was collected to analyze its form and color. Analysis of the form of symbol revealed that the most anthropogenic symbols were made with artificial objects, and among them, the number of symbols with crosses, hearts and human forms were higher. The color analysis showed that more than 50% of symbols consisted of two colors and the main colors were blue and green. It is expected that this research data will be used as a reference in the design of the symbolism of nursing hospitals, which will help consumers choose and develop strategies for hospital management in order to compete with the ever-increasing demand of nursing hospitals and hospital competition.

• Spatial Information Research
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• v.19 no.2
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• pp.9-18
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• 2011

The purpose of this research is to evaluate an accurate biotope area ratio model with efficiency and convenience of database management through promoting sustainable development to provide people amenities in a new town. In particular, the biotope area ratio is used not only in the environment impact assessment but Green building certification criteria. But now there is no any index map of biotope. So it is very hard to implement with data for supplement results. In this research, we suggest the model of integrated attributable information. The evaluation of biotope area ratio is to include a basic land use planning map and a building coverage area which is a wall of greening surface and roof. In case of non building coverage area, the evaluation of biotope area ratio is to include water space, artificial ground, natural ground and pervious gap-pave. A weighted value on the spatial information is combined into the information. And then the merged one is given a land use planning information in a block. In the weighted value on the space type information, it is possible to in its circumstances. Therefore, it can be substituted a correspondence of numerical change for various values elastically in this model.

• Weed & Turfgrass Science
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• v.4 no.2
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• pp.118-123
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• 2015

Metagenomics is a powerful tool to isolate novel biocatalyst and biomolecules directly from the environmental DNA libraries. Since the metagenomics approach bypasses cultivation of microorganisms, un-cultured microorganisms that are majority of exists can be the richest reservoir for natural products discovery. To discover novel herbicidal substances from soil metagenome, we established three easy, simple and effective high throughput screening methods such as cucumber cotyledon leaf disc assay, microalgae assay and seed germination assay. Employing the methods, we isolated two active single clones (9-G1 and 9-G12) expressing herbicidal activity which whitened leaf discs, inhibited growth of microalgae and inhibited root growth of germinated Arabidopsis seeds. Spraying butanol fraction of the isolated active clones' culture broth led to growth retardation or desiccation of Digitalia sanguinalis (L) Scop. in vivo. These results represent that the screening methods established in this study are useful to screen herbicidal substances from metagenome libraries. Further identifying molecular structure of the herbicidal active substances and analyzing gene clusters encoding synthesis systems for the active substances are in progress.

• Journal of Sericultural and Entomological Science
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• v.53 no.2
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• pp.87-91
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• 2015

There is no specific data on Entomogenous fungus (DongChungHaCho) in accordance with the silkworm varieties, despite of very high value industrial use as functional materials at domestic and abroad. In this study, we investigated culture condition and characteristics of Paecilomyces tenuipes in 3 silkworm cultivars and 2 specific silkworm breeds. Infection rate of P. tenuipes for silkworm varieties was the highest Kumokjam, followed by Baegokjam, Daeseongjam, Golden silk, Yeonnokjam in that order. The optimum culture conditions were as follows: dark condition, $22^{\circ}C{\pm}1$, and about $4cm^2$ in planting density per pupa. Also, we have developed annual production technologies of P. tenuipes. First, in order that the moisture content of the infection pupa became 3% or less in the natural condition. Second, the dried pupa must be vacuum-packed and was kept under $4^{\circ}C$. Finally, by restoring the moisture content of the dried pupa and culture in optimal condition, the technique for annual production of the P. tenuipes was achieved. Therefore, we expect that the use of Kumokjam and annual production technique will contribute significantly to farm income.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.33 no.3
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• pp.110-121
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• 2021

The importance of tidal flats lost due to industrialization has recently received attention, and attention is being paid to the creation of artificial tidal flats and maintenance of natural tidal flats. However, there is still a lack of understanding about the behavioral characteristics of mud, mud, and sand that form tidal flats. Although research on the movement characteristics of mixed soils such as tidal flats has been conducted through field investigations and hydraulic experiments, interest in developing a numerical model based on these results has not yet reached. In this paper, the purpose of this paper is to establish a mixed soil model that can efficiently manage the low quality of the tidal flats. In constructing a model for reproducing the surface movement of mixed soil, the numerical stability of the reproduction and movement of sand and mud constituting the mixed soil in the numerical model should be considered first, so first, the volume of sand and mud constituting the mixed soil A mixed soil model representing the relationship was proposed based on a topographical diagram representing the geometric structure of the mixed soil. In order to consider the dry bulk density of the mixed soil, it was possible to consider the dry bulk density of the mud by introducing the water content of the mud containing water. In addition, it was confirmed that the mud and sand movement calculation according to the slope collapse of the mixed soil was stably performed through the calculation of the slope collapse of the mixed soil through the numerical analysis model to which the proposed mixed soil model was applied.

• Journal of Wetlands Research
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• v.24 no.4
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• pp.213-223
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• 2022

This study was conducted to establish a Habitat Suitability index (HSI) based on literature research and field surveys on ecology and habitat of 'Hynobius leechii'. And this study will be used as basic data for qualitative evaluation of habitat environment. The survey sites were divided into natural habitats close to the prototype habitat and artificial restoration areas where Hynobius leechii was monitored. So the types of habitats were diversified. Hynobius leechii is a vulnerable species to climate change because it is affected by the microhabitat and has low mobility. HSI variables of Hynobius leechii were extracted through domestic and overseas literature, and standards were extracted from literature research and field survey. The standards were presented as a value of the physical allowable category in consideration of realization. To verify the study, an in-depth consultation was conducted by amphibians experts. HSI variables of Hynobius leechii were included 9 variables such as Overstory canopy cover(%), Understory cover(%), Water-pH, Soil-pH, Soil relative humidity(%), Leaf litter depth(cm), Rock substrates (%), Type of Coarse woody, Distance from Street or Pollutant(m).

• Land and Housing Review
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• v.14 no.1
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• pp.83-97
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• 2023

The study aims to provide an academic basis for the preservation and restoration of abandoned paddy wetland and the enhancement of its carbon accumulation function. First, the temporal change of the wetlands was analysed, and a typological classification system for wetlands was attempted with the goal of carbon reduction. The types of wetland were classified based on three variables: hydrological environment, vegetation, and carbon accumulation, with a special attention on the function of carbon accumulation. The types of abandoned paddy wetlands were classified into 12 categories based on hydrologic variables- either high or low levels of water inflow potential-, vegetation variables with either dominance of aquatic plants or terrestrial plants, and three carbon accumulation variables including organic matter production, soil organic carbon accumulation, and decomposition. It was found that the development period of abandoned paddy analyzed with aerial photographs provided by the National Geographic Information Institute happened between 2010 and 2015. In the case of the wetland in Daejeon 1 (DJMN01) farming stopped by 1990 and it appeared to be a similar structure to natural wetlands after 2010 . Over the past 40 years the abandoned paddy wetland changed to a high proportion of forests and agricultural lands. As time went by, such forests and agricultural lands tended to decrease rapidly and the lands were covered by artificial grass and other types of forests.