• Journal of Environmental Impact Assessment
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• v.30 no.4
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• pp.203-214
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• 2021

Assessment of benthic quality status was implemented along the subtidal areas of Jindo and Jejudo to understand faunal structure of polychaete assemblages and ecological quality of the benthic environment. Sediment analysis was characterized by well sorted of both mud and sand in Jindo, and a little higher sand in Jejudo instead. A total of 68 polychaete species were found at 14 sampling stations with a mean density of 231 inds./m², and 61 species, 167 inds./m² and 62 species, 295 inds./m² in Jindo areas and Jejudo areas. Dominant species found in Jindo areas were Heteromastus filiformis, Ampharete arctica, Prionospio sp., Sigambra tentaculata, Thelepus sp. and Amphicteis gunneri, Ampharete arctica, Prionospio sp., Spiochaetopterus costarum, Heteromastus filiformis in Jejudo. With a help of cluster analysis, it was found that the sampling stations showed distinctive pattern of the distribution pattern and benthic quality status in Jindo and Jejudo except sampling station numbers 5 and 6, respectively. AMBI analysis the results were 1.2-3.4, grade V benthic polychaetes did not appear. It was evident that both Jindo and Jejudo had different sedimentary characteristics as well as distribution pattern of polychaete assemblages.

• 한국지구과학회:학술대회논문집
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• 2005.02a
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• pp.126-134
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• 2005

최근 중생대 전기 백악기(약 1.2Ma) 지층이 분포하는 경북 고령의 지역에서 대량으로 발견된 골설목(骨舌目, Osteoglosomorpha) 어류화석을 기재하고 특징을 살펴본 후 현생골설목과의 관계를 조사하고, 아울러 다른 나라에서 발견된 것과의 비교연구를 통해 우리나라에서 발견된 어류화석의 고생물학적 의의를 살펴보았다. 경상층군에서 발견된 어류 화석군은 Semionotiformes, Amiiformes목, 골설목, 당멸치목(Elopiformes), 여을멸목(Albuliformes), Ichthyodectiformes목 등으로 구성되어 있으며, 그중 골설목(Osteoglossiformes)과 여을멸목(Albuliformes)이 가장 풍부하다. 경상어류화석군은 한국의 중생대 백악기 지층에서는 유일한 어류화석군이다. 또한 어류화석과 함께 발견된 여러 화석 및 지질학적 자료를 토대로 어류화석 서식 당시의 고환경을 유추하였다.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.05a
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• pp.281-282
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• 2001

본 연구는 현재까지 국내에서 가숭어, Chelon lauvergnii의 성숙 및 인공 종묘 생산에 관한 구체적인 연구 보고는 매우 미흡한 실정임을 고려, 가숭어의 효과적인 인공 종묘 생산을 위한 기초 자료로서 산란기 특성 조사 및 부화 자어에 대한 rotifer, Artefnia, 배합사료 공급에 따른 성장과 생존을 조사하였다. 또한 rotifer와 brine shrimp, Artemia nauplius를 오징어 간유, 식물성 플랑크톤 건조 분말인 Maxima$^{TR}$ , Chlorella sp.로 각각 영양 강화한 후 치어에 공급시 자어의 성장과 생존에 대한 그 효과를 비교 분석하였다. 아울러 밀도별 사육 실험을 통한 적정 밀도를 규명하여 가숭어 종묘 생산시 효율적이고 경제적인 기술을 개발하고자 본 연구를 수행하였다. (중략)

• Korean Journal of Environmental Agriculture
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• v.35 no.1
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• pp.79-86
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• 2016

BACKGROUND: This study was initiated to quantitatively evaluate the effects of five heavy metals on the growth and P removal efficiencies of Alcaligenes sp., known as the Phosphorus Accumulating Organisms (PAOs). It was cultivated in the batch system with five heavy metals, such as Cd, Cu, Zn, Pb and Ni, added in single and binary mixtures, respectively.METHODS AND RESULTS: IC₅₀ (half of inhibition concentration of bacterial growth) and EC₅₀ (half of effective concentration of phosphorus removal Efficiencies) were used to quantitatively evaluate the effects of heavy metals on the growth and phosphorus removal Efficiencies of Alcaligenes sp. In addition, Additive Index Value (A.I.V.) method was used to evaluate the interactive effects between Alcaligenes sp. and heavy metals. As a result, as the five heavy metals were singly added to Alcaligenes sp., the greatest inhibitory effects on the growth and P removal efficiencies of each bacteria was observed in the cadmium (Cd). In the binary mixture treatments of heavy metals, the treatments of lowest IC₅₀ and EC₅₀ were the Cd + Cu treatment. Based on the IC₅₀ and EC₅₀ of the binary mixtures of heavy metals treatments, most interactive effects between the heavy metals were found to be antagonistic.CONCLUSION: Based on the results obtained from this study, it appears that they could provide the basic information about the toxic effects of the respective treatments of single and binary mixtures of heavy metals on the growth and P removal efficiencies of Alcaligenes sp. through further study about the characterization of functional proteins involved in toxic effects of heavy metals.

• Geotechnical Engineering
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• v.14 no.5
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• pp.235-247
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• 1998

The IIA(Inchon International Airport) which will function as the HUB airport in the northeast Asian region in the upcoming 21th century will be located in the reclaimed land with sand dredged in the vicinity of project area between Youngjong and Yongyu islands. The original ground is composed of soft clayey silt (ML) or silty clay (CL). The reclaimed land is classified as being SP-SM and having poor gradation of Cu<3 which resulted in the anticipation for difficulty in compaction (compaction index = 0.6~0.7). This anticipation shedded light on the necessity of performing test compactions for the thickness of 3~5meters of reclaimed land, aiming at the discovery of effective and economical compaction method. Upon the call for the test compaction performance 4 different compaction methods have been selected for trial from the research done on the international and local academic papers, past experience with compaction works, and their written materials. For the precise interparetation of test results, the ground survey and measurements have been performed. The Hydraulic Hammer Compaction has been chosen as the most optimum in accordance withe the test results.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.1 no.1
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• pp.52-57
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• 2002

A simulation tool for an optimal ATIS design and drivers' dynamic route choice behavior analysis is developed, which is applicable to urban networks. Due to the difficulty to make drivers feel the time pressure according to traffic conditions, current SP questionnaire survey type surveys have a limitation to capture correct driver reactions to real-time traffic Information provision. The simulator Is a web-based upgraded version, named WATiSim (Web-based ATIS Simulator), to quickly perform a wide population survey with a minimal cost using INTERNET Furthermore, the time pressure issue is lessened by its interface and simulation modules. After WATiSim mimicked a VMS based ATIS in a partial network of Seoul Metropolitan, reactions of drivers to various traffic conditions were surveyed through INTERNET and analyzed using a logit model. Drivers under the ATIS environment clearly understood the provided traffic information, and their reactions were closely related to traffic conditions, scheduled delay, trip purposes as well as toll charge if any.

• Journal of the Korean Society for Railway
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• v.20 no.5
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• pp.683-691
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• 2017

It is important to compare the present condition of railway and marine freight transportation corridors to make good progress for freight transportation to the Eurasia region. This study is performed to investigate the current state of international corridors and to analyze mode choice characteristics between railway and marine transportation in the Eurasia region. SP (Stated Preference) data surveyed from international forwarders who are dealing with international freight shipment to the Eurasia area was used. The analysis results show that there is a competitive relationship between railway and marine transportation to Eurasia, and that the accessibility to each mode has an influence on freight mode choice. It is expected that this study will provide good insight to make effective use of various international corridors in the Eurasia region.

• Proceedings of the Ginseng society Conference
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• 1988.08a
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• pp.129-132
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• 1988

Ginseng is cultivated in Korea. Japan. China. the Soviet Union and North America. Studies of the macroclimate of each of these producing areas shows that ginseng has certain requirements for production. In each producing area the microclimate is modified in different ways. Comparisons of recent research data from North America. Korea and China is presented in order to define. more precisely. the various microclimate requirements for ginseng production. These include studies of light interception as influenced by different shade materials. In North America. wood. woven black polypropylene and knitted polyethylene shade are used. whereas in China. dried grasses are bound together in layers with wire and polyvinylchloride is inserted between the layers. The influence of these various shade materials in terms of crop grow1h and root yield are presented. The major effect of temperature seems to be on root growth. During much of the growing season optimum temperatures for root grow1h are not reached. Growth analysis data for different age plants are being used to show the effects of different soil temperature regimes on distribution of dry matter between the shoot and root.

• Korean journal of applied entomology
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• v.59 no.2
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• pp.93-107
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• 2020

Adults of seven noctuid potential pests (Spodoptera frugiperda, S. litura, S. exigua, Ctenoplusia agnata, Mythimna loreyi, Athetis dissimilis, and A. lepigone) of soybean and maize in Suwon, Korea were identified by their morphological characteristics in the wing pattern and male genitalia and partial mitochondrial DNA sequences of cytochrome c oxidase subunit 1 gene. The generation number of adults that emerge annually in six species (except A. lepigone) was estimated from the data on density fluctuations of adults caught in sex pheromone traps in 2019 and the forecasted data using temperature-associated development and reproduction models for those species. S. frugiperda adults were caught from July 27th to October 31st in 2019, and hence were initially estimated to emerge three times per year. But, it was finally expected that S. frugiperda adults could possibly emerge a total of four times per year in Suwon, considering larval emergence observed during mid- and late June in other areas. Adult emergence of S. litura, S. exigua, C. agnata, and M. loreyi in 2019 was observed from May 29th to November 6th, from May 14th to November 6th, from May 26th to October 25th, and from May 31st to November 23rd, respectively. Annual adult emergence of these four species was estimated as at least four times. Adults of A. dissimilis were caught from May 26th to September 11th in 2019, and adult emergence was estimated at only twice per annum. It was postulated that the first adult populations of five species except the two Athetis species were probably migrated from other areas.

• Korean Journal of Food Science and Technology
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• v.25 no.6
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• pp.689-693
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• 1993

${\alpha}-galactosidase$ releases galactoside from raffinose and stachyose which are the major sugars in soybean, Although raffinose and stachyose were known as flatulence factors, these sugars were recently claimed as bifidus factors. In this experiment we studied the properties of ${\alpha}-galactosidase$ and its production from Bifidobacterium sp. Int-57. Int-57 produced higher level of ${\alpha}-galactosidase$ than other intestinal bacteria. The production of ${\alpha}-galactosidase$ was greater when grown on raffinose compared with other carbohydrates tested. Partially purified ${\alpha}-galactosidase$ was obtained after sonication of harvested cell pellet followed by DEAE-cellulose chromatography and Sepharose CL-6B gel filtration, and assayed using PNP-${\alpha}-galactosidase$ as a substrate. Optimum pH for activity was 7.0 and optimum temperature was $40^{\circ}C$. At 5 mM concentration of metal ions, $CoCl_{2}\;and\;CuCl_{2}$ and inhibited the enzyme activity by 33% and 21% respectively. The enzyme was shown to hydrolyse genuine substrates, i.e. raffinose and stachyose.