• Proceedings of the Korea Water Resources Association Conference
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• 2005.05b
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• pp.1393-1397
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• 2005

홍수유출을 저감시키기 위해서 유역의 저류기능을 강화시킬 수 있는 댐 건설은 이수적인 측면에서 안정적인 용수공급을 보장해주는 수단으로 겸용되어 왔으며, 특히 다목적댐이 건설되면서 하도의 첨두홍수유출량을 줄이는데 크게 기여해 왔다. 하지만 그로 인해 물의 흐름이 막히는 정체수역이 증가하고 있으며, 생활오수, 산업폐수의 발생은 정체수역에서의 영양염류 부하량을 증가시켜 부영양화를 초래하고 있다. 수생식물은 태양빛을 받아 광합성 작용을 하여 수중에서 성장하면서 수중의 유$\cdot$무기물질을 영양소로 섭취함으로써 수질을 정화시키는 작용을 하게 된다. 영양염류 부하량이 큰 정체수역의 오염된 물은 식물의 성장활동에 의해서 어느 정도 정화시킬 수 있으며, 이와 같이 수중에 식물을 식재하기 위해서는 식물이 하상에 쉽게 그리고 지속적으로 성장하고 번식활동을 할 수 있는 여건이 필요하다. 따라서 본 연구에서는 Mattress/Filter를 정체수역에 설치함으로써 이러한 식물의 성장과 번식을 도와줄 수 있는 환경조건을 제안하였다. 연구결과, Mattress에 식재한 갈대, 줄 및 애기부들의 피도는 $60-80\%$ 정도로 나타났다. 각 Mattress의 식물군집에는 초기 식재한 식물의 우점도가 가장 높았으나 갈대와 줄 군락의 경우 다른 종이 많이 출현하는 것으로 나타났다. 갈대 군락에서는 갈대가 크게 우점하였으나 그 외에 돌피, 하늘지기, 여뀌바늘 등이 우점하는 것으로 나타났다. 또한 줄 군락에서는 역시 줄이 크게 우점하였으나 방동사니, 돌피, 조개풀 등이 출현하였다. 애기부들 군락에서는 애기부들외에 세모고랭이와 미국가막사리 두가지 종만 출현한 것으로 나타났다. 갈대와 줄 군락의 출현 종수는 각각 7과 11이었으며, 다양도지수가 1.67, 2.18로 식물다양성이 크게 증가한 것으로 나타났다. 수질은 BOD 10mg/L, TN 15mg/L, TP 2.0mg/L이하로 이를 유등천 상류부에 공급할 경우 유등천의 수질은 BOD 6.7mg/L, TN 9.80mg/L, TP 0.90mg/L를 나타낼 것으로 예측된다. 고도처리시설의 도입 후 금강 합류점에서 갑천의 예측 BOD는 7.4mg/L로 현재 9.0mg/L에 비하여 개선되지만 이는 금강수계 오염총량 관리계획의 시$\cdot$도 경계지점 목표수질인 5.9mg/L를 만족시키지 못하므로, 이를 만족시키기 위해서는 방류수 BOD 7.2mg/L이하로 처리해야 할 것으로 판단된다.which support only concepts or image features.방하는 것이 선계기준에 적합한 것으로 나타났다. 밸브 개폐에 따른 수압 변화를 모의한 결과 밸브 개폐도를 적절히 유지하여 필요수량의 확보 및 누수방지대책에 활용할 수 있을 것으로 판단된다.8R(mm)(r^2=0.84)$로 지수적으로 증가하는 경향을 나타내었다. 유거수량은 토성별로 양토를 1.0으로 기준할 때 사양토가 0.86으로 가장 작았고, 식양토 1.09, 식토 1.15로 평가되어 침투수에 비해 토성별 차이가 크게 나타났다. 이는 토성이 세립질일 수록 유거수의 저항이 작기 때문으로 생각된다. 경사에 따라서는 경사도가 증가할수록 증가하였으며 $10\% 경사일 때를 기준으로 $Ro(mm)=Ro_{10}{\times}0.797{\times}e^{-0.021s(\%)}$로 나타났다.천성 승모판 폐쇄 부전등을 초래하는 심각한 선천성 심질환이다. 그러나 진단 즉시 직접 좌관상동맥-대동맥 이식술로 수술적 교정을 해줌으로써 좋은 성적을 기대할 수 있음을 보여주었다.특히 교사들이 중요하게 인식하는 해방적 행동에 대한 목표를 강조하여 적용할 필요가 있음을 시사하고

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.9
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• pp.1281-1287
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• 2012

In this study, soy milk jellys with medicinal herbs (MH) composites showing cognitive effects were prepared and their characteristics were examined. Eight kinds of medicinal herbs were extracted with hot water and added to soy milk based on their contents. Medicinal herbs showed cognitive effects, namely promoting acetylcholinesterase (AChE) inhibition. In the preparation of soy milk jellys containing MH extracts of various contents (0%, 5%, 10%, 15% and 20%), pH of all groups significantly (p<0.05) decreased with increasing MH extracts compared to the control group. The brix of the soy milk jellys was the highest in the 5% content of MH extracts among all groups. The "a" and "b" values of soy milk jellys increased with the content of MH extracts, while the "L" value decreased adding to the content of MH extracts compared to the control. The hardness, gumminess, and chewiness of soy milk jellys were improved the most by the addition of 15~20% MH extracts, while the fracturability, adhesiveness, springiness, cohesiveness, and resilience of soy milk jelly was not significantly different (p<0.05) among all groups. Through a sensory evaluation, it was revealed that the taste, texture, overall preference, flavor, and sweetness of soy milk jellys was not significantly different (p<0.05) among all groups. Therefore, since the addition of 20% MH extracts did not significantly alter the sensory evaluation, it can usually be adjusted to make soy milk jellys with cognitive effects.

• Journal of the Institute of Electronics and Information Engineers
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• v.49 no.10
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• pp.60-68
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• 2012

Current wireless sensor networks are considered to support more complex operations ranging from military to health care which require energy-efficient and timely transmission of large amounts of data. In this paper, we propose an adaptive temporal suppression algorithm which exploits a temporal correlation among sensor readings. The proposed scheme can significantly reduce the number of transmitted sensor readings by sensor node, and consequently decrease the energy consumption and delay. Instead of transmitting all sensor readings from sensor node to sink node, the proposed scheme is to selectively transmit some elements of sensor readings using the adaptive temporal suppression, and the sink node is able to reconstruct the original data without deteriorating data quality by linear interpolation. In our proposed scheme, sensing data stream at sensor node is divided into many small sensing windows and the transmission ratio in each window is decided by the window complexity. It is defined as the number of a fluctuation point which has greater absolute gradient than threshold value. We have been able to achieve up about 90% communication reduction while maintaining a minimal distortion ratio 6.5% in 3 samples among 4 ones.

• Journal of Navigation and Port Research
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• v.37 no.5
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• pp.551-557
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• 2013

In this paper, we manufactured portable inflatable kayak using ultra high pressure drop stitch. by improving inflatable kayaks' performance with a design using the extra-high-voltage special space paper, they were manufactured to go near to performance of hard shell kayaks. The kayaks were manufactured having all merits of the performance of hard shell kayaks and functionality and portability of the inflatable kayaks, and through performance evaluation of test products, the performance was compared with previous hard shell kayaks. About 6 knot of target speed in the verification result of resistance performance, the developed kayak was more excellent than the HOBIE-KONA kayak by 12.33%. In case of same displacement in a result of inclination test, the centroid of the developed kayak was less distributed by 22.7% than the HOBIE-KONA kayak, based on the bottoms of the ships. This makes the difference for righting arm (GZ) lessened to some degree because the developed kayak is lower than the HOBIE-KONA kayak in the centroid. In the dynamic stability of ship bodies, the HOBIE-KONA kayak showed a little excellent performance. However, in rudder force and resistance factor, the developed kayak was more outstanding than the HOBIE-KONA kayak.

• Korean Journal of Soil Science and Fertilizer
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• v.32 no.4
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• pp.375-382
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• 1999

In order to investigate the contamination characteristics of the heavy metals in the mine tailings of abandoned gold mine and its surrounding agricultural soils, a sequential extraction procedure of increasing reactivity in the dissolution processes of the heavy metals(Cd, Cu, and Pb) which were associated with solid and/or solution phase in soils was attempted to partition into six particulate fractions : exchangeable, bound to carbonate, bound to Fe-Mn oxides, bound to organic matter, residual, and soluble. Among indigenous heavy metals in the mine tailings, Pb was the most abundant and Cu and Cd were followed by. Fractionation result of Pb obtained from the triplicate samples of the mine tailings were in the order of Fe-Mn oxide> Carbonate> Residual> Organic> Exchangeable> Soluble, while Wolgok series were Exchangeable > Fe-Mn oxide > Carbonate> Organic> Residual> Soluable. However the other heavy metals studied were not followed this trend. The fractionation results of mine tailing and agricultural soils demonstrated that different geochemical fractions were operationally defined by an extraction sequence that generally followed the order of decreasing solubility. Therefore potential mobility and bioavailability of heavy metals as toxic pollution sources can be evaluated when studying the pollution levels of heavy metals in soils.

• 보존과학연구
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• s.35
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• pp.45-55
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• 2014

The small dining tables which are made of bamboo were deteriorated condition when those were excavated from Mado shipwreck No.1. Therefore, preliminary test was conducted for consolidation (Sucrose, Dammar gum, Cetyl alcohol and Polyethylene glycol 4000) then impregnated and vacuum freeze dried. After the test, since the treatment with vacuum freeze drying using an aqueous solution of PEG 4000 keep the shape well the most and present bright colour, waterlogged archaeological bamboo conserved with vacuum freeze drying using an aqueous solution of PEG 4000. One bamboo table consolidated with soluble PEG 4000 from 10% to 40%, then vacuum freeze dried. Another impregnated with soluble PEG 4000 from 10% to 70%. After that, it was separated and held in polycarbonate sheet for preventing bending during dry. The small dining tables are the three dimensional shapes and have some loss. Therefore the mounting for support tables were necessary which are made of acrylic sheet. It keep the table shape and make it convenient for storage and handling.

• Journal of the Korea Institute of Building Construction
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• v.15 no.6
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• pp.579-587
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• 2015

In this paper, microencapsulated healing agent was embedded in the polymer matrix to obtain self healing properties. Microencapsulation of methacrylate using polyurea-formaldehyde as a shell material and studied the effect of agitation rate on capsule characteristics such as size, shell thickness, and surface morphology. The formation of microcapsules was confirmed by FTIR and TGA, and capsule characteristics were studied by optical microscopy and SEM. The self-healing effect was evaluated using permeability measurements and further confirmed by surface analytical tools including optical microscope. According to the experimental results, the microencapsulated healing system has the self-heaing ability for artificial cracks.

• Journal of Science and Technology Studies
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• v.9 no.2
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• pp.51-78
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• 2009

Usually, Technological failures have been recognized as a mundane and inevitable process of trial and error for finally achieving success, or pathological technologies clearly different from success. These approaches easily ignore that a failed technology also constructed complex technological networks with various actors for some times. Consequently, failed technologies failed not only technological realization, but also got a proper evaluation. This paper explore the emergence and decline of the city phone project (CT-2 technology), the very typical failure cases in the telecommunications industry at Korea. This story shows that the city phone project with low-price and low-technology could constructed a stable network at agreement the result from interaction between various actors, and then, changed because various actors gave technologies different meaning and desire. Finally, it suggests that collapse of its technological network was attributed to uncertain future and contingent, rather than technological limits.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.30 no.2
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• pp.153-162
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• 2012

In this paper, we propose a new shape similarity measure for M:N polygon pairs regardless of different object cardinalities in the pairs. The proposed method compares the projections of two shape functions onto Zernike polynomial basis functions, where the shape functions were obtained from each overall region of objects, thus not being affected by the cardinalities of object pairs. Moments with low-order basis functions describe global shape properties and those with high-order basis functions describe local shape properties. Therefore several moments up to a certain order where the original shapes were similarly reconstructed can efficiently describe the shape properties thus be used for shape comparison. The proposed method was applied for the building objects in the New address digital map and a car navigation map of Seoul area. Comparing to an overlapping ratio method, the proposed method's similarity is more robust to object cardinality.

• Proceedings of the Korea Water Resources Association Conference
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• 2012.05a
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• pp.669-673
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• 2012

제방안전성 모니터링은 제방파괴로부터 국민의 생명과 재산을 보호하는데 필요한 정보를 얻을 수 있는 하나의 방법이 될 수 있다. 근래에 미국은 2005년 허리케인 카타리나에 의해 2,000여명의 인명손실을 경험하였고 2011년 3월 일본은 도후쿠지역의 초강력 지진에 의한 쓰나미로 인해 수만명의 인명과 후쿠시마 원자력 발전소의 침수로 지금까지 방사능 누출 차단작업을 벌이고 있다. 국내에서는 4대강 복원사업으로 주요 국가 하천 구간에서 홍수 및 체제 불안정에 의한 제방붕괴사고위험이 현격하게 줄어들었으나 제방의 안전성은 더욱 강조되고 있다. 즉 신설된 보 주변, 배수통문 신설구간 그리고 제방누수 예상지점 등에서는 아직 안전한 상태라고 확신할 수 없으며 지속적인 모니터링이 요구된다. 따라서 본 연구에서는 광섬유를 이용하여 개발한 간극수압 및 온도 센서 등을 위험예상지점에 설치하고 정보시스템을 통하여 어떻게 관리 할 것인가에 대한 사전 검토를 계획하였다. 이를 위하여 제방에 센서를 설치하기 전에 주요 검토사항에 대하여 연구분석하였다. 주요 검토사항에는 설치하고자 하는 지점의 제방거동 메커니즘 예측, 왜 계측시스템을 설치하는지에 대한 목적에 대한 평가, 설치 지점의 제방의 토질공학적 문제점 파악, 모니터링 대상 매개변수 혹은 항목 선정, 조사대상 항목의 변화정도를 예측하여 거동 범위 확정, 적정 계측기기 설치 지점을 선청, 계측기기 선정, 자동화 혹은 실시간 정보시스템에 필요한 사항 결정, 관측에 영향을 미치는 인자들의 기록 계획, 정보의 타당성 확보를 위한 필요사항 정립, 비용의 결정, 장기 예측 계획, 정기 검 보정 및 관리 계획, 자료수집 및 관리계획, 자원의 공조 및 생애주기 비용 등을 포함하였다.