• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2012.03a
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• pp.86-86
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• 2012

고속방사소재는 연신공정이 없이 6,000m/min이상의 고속방사공정만이 있으므로 원가절감이 되고, 빠른 냉각, 높은 변형속도 등으로 섬유의 결정화도, 분자와 결정의 배향 및 모폴로지(morphology) 변화 등의 기계적 및 섬유상의 특성이 종래의 원사와는 다르게 된다. 방사속도가 증가함에 따라 배향도가 증가하면서 결정영역 또한 증가한다. 또한 기존 연신사에 비해 큰 결정크기를 갖는데 방사속도에 에 따른 방사응력의 증가가 응력유도 결정화도를 유발하여 결정크기 및 결정화도를 증가시키고,따라서 고분자의 용융점도를 고온측으로 이동시키는 현상을 나타내게 한다. 즉, 고속방사에 있어서는 연신에 필요한 임계응력 이상의 과도한 응력이 가해짐으로 인해 결정구조가 일반 연신사에 비해 현저히 발달한다는 것을 알 수 있다. 고속방사 원사를 통일한 조건으로 염색하는 경우 기존의 연신사보다 염착량이 많아 농색으로 염색이 가능하고 염착속도도 빠른 특징을 갖는 데이는 고속방사 원사의 비결정 배향이 낮고 느슨한 구조를 갖기 때문에 염료의 침투가 용이한 것으로 해석되고 있다. PET 섬유는 방사 후 형태안정성을 부여하기 위해서 염색 전처리 공정에서 열을 가하게 된다. 이런 과정에서 섬유의 미세구조가 변하게 되는데,특히 고속방사의 경우 섬유 형성과정이 연신사와는 다르므로 열에 의한 구조 변화와 이에 따른 염색성 변화에 대해 검토해 보는 것은 고속방사의 응용면에서 꼭 필요하다. 본 연구에서는 고속방사소재의 가장 단점인 잔류신도, 저수축현상, stiff감을 보완하면서 고속방사소재의 장점인 심색성을 부각시켜 차별화된 복합사 제조기술을 개발하기 위해 그 기술개발이 기초 연구로서 일반 일반 DTY사와 고속방사소재인 HOY사를 이용한 DTY사의 물성 및 염색 특성을 비교분석 하고자 한다.

• Applied Biological Chemistry
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• v.42 no.3
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• pp.199-204
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• 1999

Soft-rot bacterial pathogen, Erwinia sp., was isolated from chinese cabbage tissue showing soft-rot symptom. This bacterial strain caused soft-rot to chinese cabbage and potato, and identified as Erwinia chrysanthemi PY35(Ech PY35). Ech PY35 have extracellular CMCase, pectinase, pectate lyase, and protease activity, but not hemicellulase activity. The results of the microscopy showed that chinese cabbage tissue and potato tissue were macerated by infection of Ech PY35. In analysis of the CMCases activity in the total protein of Ech PY35, three CMCases were detected as intracellular protein while two CMCases were as extracellular protein by CMC-SDS-PAGE direct stain method.

• Korean Journal of Materials Research
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• v.2 no.3
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• pp.197-201
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• 1992

The temperature dependence of the magentic moment was determined for the system of high $T_{c}$ superconductor $Y_{1-X}Sm_{x}Ba_2Cu_3O_{7-y}$ with x=0, 0.2, 0.4, 0, 6, 0.8 and 1.0. Also the magnetic susceptibility and the magnetic critical current density were measured from the magnetic hysterisis loops obtained at 30 K. From the results of the magnetic susceptibility measurements, the high $T_{c}$ phase were ranged from 14.7 to 49.1%. The values of the magnetic critical current densities were in the range of $10^3~10^4A/cm^2$. The penetration depth was approximately ninety times larger than the coherence length.

• Proceedings of the Korea Water Resources Association Conference
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• 2008.05a
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• pp.1240-1243
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• 2008

제주도는 연평균 강우량이 1,975mm에 달하는 우리나라 최대의 다우지역이며 투수성이 좋은 다공질 화산암류 및 화산회토로 이루어져 있어 총 강우량의 48.5%에 이르는 빗물이 지하로 침투하여 대부분의 하천들은 건천을 이루고 있다. 제주도의 143개 하천 중 6개의 하천을 제외한 전 하천들은 건천의 형태를 이루고 있어 지표수의 발달이 매우 빈약하다. 본 연구에서는 장기 강우-유출 모형인 SWAT(Soil and Water Assessment Tool) 모형을 적용하여 제주도 주요하천의 유출량을 산정하고자 한다. 143개 하천 중 제주도 동부유역의 천미천과 북부유역의 외도천을 연구대상유역으로 선정하여 SWAT 모형을 적용하였다. 연구 대상유역에 대한 SWAT 모형의 입력자료인 수문 기상자료(Precipitation, Solar Radiation, Wind Speed, Climate, Humidity)와 지형자료(DEM(Digital Elevation Model), Land Use, Soil Type)를 구축하였으며, 동시에 모형의 보정 및 검증을 위하여 천미천 외도천 유역의 실측 유출자료를 수집하여 정리하였다. 모델의 입력자료를 구축하고 SWAT 모형을 이용하여 천미천 외도천 유역의 유출 모의를 하였고, 유출 모의 결과를 바탕으로 하여 수문관련 매개변수들의 민감도 분석을 하였으며, 민감도 분석을 통하여 보정을 수행하였다. 보정을 수행한 결과를 바탕으로 하여 천미천 외도천의 유출모의 결과를 분석하였으며, 향후 제주도에 필요한 연구결과 활용방안에 대하여 검토한 이상의 결과들로부터 제주도 하천에 대하여 SWAT모형을 적용한 결과 장기 일 유출량 모의에 대하여 전체적으로 우수한 결과를 보이고 있다. 향후 많은 보다 많은 유출량 자료를 확보하여 본 연구의 결과와 비교 검정하여 SWAT 모형을 구축한다면 제주도 하천의 장기 일 유출량 모의를 할 수 있을 것이라 판단된다.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.4
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• pp.309-314
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• 2001

In order to promote the consumption of small red muscle fish, such as saury, sardine, herring, etc., a new conditioning technique to soften backbone and small bones was investigated by using kimchi seasoning ingredients and organic acids. In the conditioning process, various chemical changes were examined during 60 days at 15 days intervals, The decrease of moisture content and the increase of salt concentration in seasoned fish meat were good correlated respectively. In the dry salt conditioning, the moisture content was more rapidly decreased than wet salt conditioning. The pH of fish meat during conditioning were more slowly decreased in dry salting than in wet salting. The VBN contents were suppressed under 30 mg/100 g in dry salt conditioning during 60 days at $5^{\circ}C$. The addition of rice bran in dry salting was effective on retarding lipid oxidation because the TBA value was most effectively retarded.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.417-420
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• 2008

The requirement for durability of concrete is increasing recently as a large-scale concrete structure is built. For this reason, the concern about high-durable concrete is being high. Recently, metakaoline to be profitable in economical aspect as well as to have strength and durability of level similar to silica fume is evaluated highly as new admixture. In this study, the scaling, the drying shrinkage, the chloride resistance and the air-void structure are compared for both metakaolin and silica fume concrete. According to the results, the replacement of metakaoline improved the resistance of chloride penetration, freezing and thawing in concrete. On the other hand, as metakaolin was replaced to 10%, it was similar level with OPC in the property of scaling. It was showed that replacement of only metakaoline was similar with OPC in the drying shrinkage. However, MS5 reduced the drying shrinkage about 10%. In conclusion, replacement of the metakaoline 10% is the most excellent performance in terms of durability of concrete.

• Proceedings of the Korean Geotechical Society Conference
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• 2006.03a
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• pp.75-85
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• 2006

In recent geotechnical engineering, geothermal approach has been on the horizon to deal with geoenvironmental issues, freezing and thawing problems, and seepage phenomenon in dams and embankments. In this study, geothermal characteristic through inner body of dams and its influence on the seepage flow were experimented by lab test and field instrumentation. Also, one of up-to-date temperature monitoring technique, called as multi-channel thermal line sensing, was evaluated its availability. As a result of lab test, it is found that the seepage flow has influence on the geothermal characteristic and a potential of finding phreatic line and seepage fluctuation could be possible by continuous temperature monitoring using thermal line sensing skills. These kine of geothermal information could be available to the modelling of water geo-structure interaction. Out of short-term field tests, clear water table and temperature distribution of a dam were easily found through temperature monitoring in holes located near a reservoir and holes within a depth of constant temperature layer. However, it is also found that the geothermal flow and finding seepage line could not be easily understandable through multi-channel temperature monitoring because of the existence of constant temperature field, thermal conductivity of soils and rocks, and unsaturated characteristics of geo-material. In this case, long-term geothermal monitoring is recommended to find sudden fluctuation of seepage line and amount of leakage.

• Korean journal of applied entomology
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• v.32 no.2
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• pp.123-128
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• 1993

The comparative toxicities of selected acaricides against the twospotted spider mite, Tetranychus urticae, were investigated. The ovicidal and adulticidal activities of selected acaricides were examined under different developmental stages. Fenpyroximate showed high activity throughout all developmental stages of mites. The oviposition inhibition effect of fenpyroximate was more highly effective than that of cyhexatin. At 100 ppm concentration, the effect of fenpyroximate on the residual oviposition inhibition was persistant during 25 days with 85% level, while the effect of cyhexatin gradually decreased, and then decreased to 40% at 25 days after treatment. Fenpyroximate at 100 ppm showed 100% knockdown activity within 3 hour while cyhexatin showed only 91% knockdown activity within 24 hours after treatment. Most of selected acaricides had no systemic activity, but metasystox at 800 ppm had 100% of the systemic activity at 24 hours after treatment. For the influence of temperature on the activity, fenpyroximate showed stable activity and no temperature-dependent in comparison with other selected adaricides.

• Korean Journal of Plant Taxonomy
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• v.44 no.1
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• pp.18-21
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• 2014

We report a naturalized alien species, Solanum elaeagnifolium Cav. from Chodo Isl., Samsanmeon, Yeosushi, Jeollanam-do province. The native distribution range of the species is the southwestern US and the adjacent region of northern Mexico. The species is related to S. nigrum L., but the species can be distinguished from S. nigrum by the silver green stellate trichome on the surfaces of plants, the elongated leaf shape, and the size and color of the flowers and fruits. Solanum elaeagnifolium Cav. belongs to the Solanum subgenus Leptostemonum. The species is recorded on the invasive species list in the subtropical or temperate regions of many European, Mediterranean, African, South American, Asian, and Australian countries. Therefore, we also need a careful monitoring and prevention strategy for this new invasive species in Korea.

• Journal of the Korea Concrete Institute
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• v.20 no.6
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• pp.741-746
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• 2008

Many methods have been introduced to protect the corrosion of embedded steel in RC structure. One of the methods that restrain corrosion of steel is corrosion inhibitor. The technology that delayed the progress of corrosion is developed recently by converting active rust to passive rust. However, the performance for concrete structure is not fully examined because this corrosion inhibitor is developed for normal metal product. In this study, the application of corrosion inhibitor that use tannin acid is investigated by concrete specimen. According to the results, tannin acid corrosion inhibitor does not occur reduction of workability and strength in concrete. When corrosion inhibitor is added more than 4% per cement weight, the penetration depth of chloride decrease about 10%. Also, corrosion resistance of concrete is improved because tannin acid corrosion inhibitor has an effect on converting the rust of steel into stable state. It is showed in special that the addition more than 6% is effective in corrosion resistance.