• Transactions on Electrical and Electronic Materials
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• 제13권3호
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• pp.149-152
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• 2012

The effects of amino silane coupling agent on the AC electrical treeing and breakdown behaviors in an epoxy/layered silicate (1 wt%) were examined in needle-plate electrode geometry. A layered silicate was exfoliated in an epoxy base resin by using our AC electric field apparatus. To measure the tree initiation and propagation and the breakdown rate, an alternating current (AC) of 10 kV (60 Hz) was applied to the specimen in needle-plate electrode arrangement with a $30^{\circ}C$ insulating oil bath. In the epoxy/amino silane system, the tree initiation time was 11.5 times higher and the breakdown time was 17.9 times higher than those of the neat epoxy resin. The tree initiation time in the epoxy/layered silicate (1 wt%) system with the amino silane was 2.0 times higher, and the breakdown time was 1.5 times higher than those of the epoxy/layered silicate (1 wt%) system.

• Journal of Information Processing Systems
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• 제20권1호
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• pp.131-147
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• 2024

A routing strategy based on traffic prediction and dynamic cache allocation for satellite nodes is proposed to address the issues of high propagation delay and overall delay of inter-satellite and satellite-to-ground links in low Earth orbit (LEO) satellite systems. The spatial and temporal correlations of satellite network traffic were analyzed, and the relevant traffic through the target satellite was extracted as raw input for traffic prediction. An improved gradient boosting regression tree algorithm was used for traffic prediction. Based on the traffic prediction results, a dynamic cache allocation routing strategy is proposed. The satellite nodes periodically monitor the traffic load on inter-satellite links (ISLs) and dynamically allocate cache resources for each ISL with neighboring nodes. Simulation results demonstrate that the proposed routing strategy effectively reduces packet loss rate and average end-to-end delay and improves the distribution of services across the entire network.

• International Journal of Fuzzy Logic and Intelligent Systems
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• 제16권1호
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• pp.27-35
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• 2016

Black-box classifiers, such as artificial neural network and support vector machine, are a popular classifier because of its remarkable performance. They are applied in various fields such as inductive inferences, classifications, or regressions. However, by its characteristics, they cannot provide appropriate explanations how the classification results are derived. Therefore, there are plenty of actively discussed researches about interpreting trained black-box classifiers. In this paper, we propose a method to make a fuzzy logic-based classifier using extracted rules from the artificial neural network and support vector machine in order to interpret internal structures. As an object of classification, an anomalous propagation echo is selected which occurs frequently in radar data and becomes the problem in a precipitation estimation process. After applying a clustering method, learning dataset is generated from clusters. Using the learning dataset, artificial neural network and support vector machine are implemented. After that, decision trees for each classifier are generated. And they are used to implement simplified fuzzy logic-based classifiers by rule extraction and input selection. Finally, we can verify and compare performances. With actual occurrence cased of the anomalous propagation echo, we can determine the inner structures of the black-box classifiers.

• 한국작물학회지
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• 제46권6호
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• pp.464-467
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• 2001

황칠나무의 선발된 우량개체군의 집단재배시 우량해체간의 교잡에 의해서 형성된 종자를 증식하기 위한 기내배양체계를 확립하기 위해서 기내 발아, 증식, 발근에 적합한 식물생장조절제를 구명하기 위하여 본 실험을 실시한 결과는 다음과 같다. 황칠나무 종자의 무균발아에 적합한 배지로는 MS(Murasinge Skook)기본배지가 발아율이 높고 유식물체(plantlet)의 생장이 양호하여 알맞는 배지로 판단 된다. 기내에서 신초의 증식과 생육에 효과적인 식물생장조절제는 사이토키닌(BAP 0.1~l.0 mg/l)과 오옥신(NAA 0.5~1.0 mg/l)의 혼용처리가 효과적이었다. 또한 기내의 발근은 오옥신의 첨가에서 쉽게 유도되었으며, 그 중에서 NAA1.0 mg/l첨가에서 가장 양호하였다.

• 농업생명과학연구
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• 제45권3호
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• pp.53-58
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• 2011

향료 및 약용 수종으로 가치 있는 좀목형 (Vitex negundo var. insica)의 기내증식 기술을 개발하고자 3년생 나무의 당년생 신초지로부터 채취한 신초의 기내 증식 및 발근에 미치는 생장조절제의 효과를 구명하였다. 다경줄기 유도는 0.5-2.0 mg/L BA가 첨가된 WPM 배지에서 효과적이었고, 가장 많은 줄기 수 (7.9개/절편)는 1.0 mg/L BA 농도에서 얻었다. 줄기 생장은 WPM 기본배지에서 1-2개의 우세 줄기로 자라는 특징이 있었고 길이는 3.4 cm 정도이었다. BA 2.0 + GA 0.5 mg/L 혼용처리는 증식과 더불어 생장을 촉진하는 효과를 보였다. 줄기 증식 시 처리된 생장조절제는 차후의 발근에 영향을 미치는 것으로 나타났다. 전반적으로 BA 처리로 유도된 줄기는 차후 발근도 잘되었으나 고농도 BA 처리 (4.0 mg/L)는 발근을 억제하였다. 저농도의 TDZ 처리도 BA 처리와 유사한 경향을 보였으나 0.5 mg/L 농도로 유도된 줄기는 발근이 현저히 억제되었고 그 이상의 농도에서 유도된 줄기는 전혀 발근되지 못했다. 증식 시 BA에 IBA를 혼용처리하면 증식은 물론 차후의 발근에 가장 좋은 것으로 나타났다. 이상의 결과는 약용가치가 뛰어난 좀목형의 기내배양을 통한 효율적인 증식 가능성을 보여주었다.

• 생물환경조절학회지
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• 제19권4호
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• pp.246-250
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• 2010

본 실험은 희귀 자생식물인 백서향의 삽목 증식 특성을 구명하기 위해 수행되었다. 백서향은 남부지방 해변의 산기슭에 나는 상록관목으로 이른 봄에 향기가 아주 뛰어난 식물이다. 자웅이주식물로 국내에는 대부분 수나무가 많아 채종이 어려워 종자번식이 힘든 상황이므로 삽목 방법을 통해 증식을 시도하였다. 백서향의 삽목에 적합한 토양을 찾기 위해 펄라이트, 버미큘라이트, 펄라이트와 버미큘라이트 혼용(1 : 1), 모래로 4 처리를 수행한 결과, 발근율은 각각 86.7%, 95%, 75%, 95%로 나타났다. 온도를 달리히여 3처리로 삽목을 하였더니 발근율과 뿌리길이의 생육을 살펴볼 때 $27^{\circ}C$에서 생육이 우수하였다. 시기별로 6월 19일, 7월 19일, 8월 19일에 삽목한 결과 생존율, 발근율은 통계적으로 오차 범위 내에서 공통적으로 우수하였고, 그 중 7월 삽목의 뿌리생장이 가장 우수하였다. 백서향의 삽목증식은 펄라이트와 버미큘라이트를 혼용하여 7월에 삽수를 채취하고 생육기간 중 온도를 $27^{\circ}C$로 관리히는 것이 우수한 것으로 나타났다.

• 전기학회논문지
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• 제62권11호
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• pp.1571-1577
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• 2013

Electrical tree structure is one of the most important influencing factors for electrical treeing characteristics in polymers. In this paper, we focused on the structure characteristics of electrical treeing in epoxy resins (original) insulation under different high-frequency voltages (60, 500, 1000Hz). Effects of voltage frequency on the ac electrical treeing phenomena in an epoxy resins were carried out in needle-plate electrode arrangement. To measure the treeing initiation and propagation, and the breakdown rate, constant AC of 10 kV with three different voltage frequencies (60, 500 and 1,000 Hz) was applied to the specimen in needle-plate electrode specimen at $30^{\circ}C$ of insulating oil bath. At 60 Hz, the treeing initiation time was 360 min and the propagation rate was $6.85{\times}10^{-4}mm/min$, and the morphology was dense branch type. As the voltage frequency increased, the treeing initiation time decreased and the propagation rate increased. At 1,000 Hz, the treeing initiation time was 0 min and the propagation rate was $7.81{\times}10^{-2}mm/min$, and the morphology was dense bush type.

• 한국조경학회지
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• 제34권3호
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• pp.79-90
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• 2006

Tamarix chinenis blooms twice a you and its flowers, branches and leaves make the adjustment of tree shape. Propagation methods and growth characteristics of T. chinensis were studied in order to ascertain its potential use as one of vegetation resources for coast forestation and landscaping. The study results indicated that 1 or 2 you old hard wood cuttings showed higher rooting ratio than greenwood or semi hard wood cuttings. One to one mixture between vermiculite and pearlite appeared to be the best for bed soil, and sea sand and silt(loess) mixture was the next. Sea sand and granitic soil followed after. In terms of seasonal differences, spring cuttings showed the best rooting ratio, root number, and root length. Fall cuttings followed after spring cutting, and summer cuttings showed worst results regarding rooting ratio, root number, and root length. The best rooting promotion effects of growth regulators were observed with sea sand bed soils. There was no significant difference among growth regulators in terms of rooting and shoot growth. Low concentration below 100 ppm of growth regulators was enough for rooting promotion effect. In general, the number and mean length of roots and shoots were showed the excellent records in the sites with high rooting ratio. The study result strongly showed that T. chinensis can be considered as a suitable tree for coast forestation and landscaping because of its easy cutting propagation and rapid growth on saline lands.

• 정보과학회 논문지
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• 제44권7호
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• pp.686-691
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• 2017

텔레마케팅은 지식정보화 사회가 되면서 기업 마케팅 활동의 중심축으로 발전하였다. 최근 금융 데이터에 기계학습을 적용하는 연구가 활발하게 진행되고 있으며 좋은 성과를 내고 있다. 하지만 지도학습법이 대부분이어서 많은 양의 클래스가 있는 데이터가 필요하다. 본 논문에서는 텔레마케팅의 목표 고객을 선정하는데 클래스가 없는 금융 데이터에 자동으로 클래스를 부여하는 방법을 제안한다. 준지도 학습법 중 레이블 전파와 의사결정나무 기반의 협동 학습으로 클래스가 없는 데이터를 레이블링한다. 신뢰도가 낮은 데이터를 제거한 후 두 방법이 같은 클래스로 예측한 데이터만 추출한다. 이를 학습 데이터에 추가한 후 의사결정나무를 학습하여 테스트 데이터로 평가한다. 제안하는 방법의 유용성을 입증하기 위해 실제 포르투갈 은행의 텔레마케팅 데이터를 이용하여 실험을 수행하였다. 비교 실험 결과, 정확도가 83.39%로 1.82% 향상되고, 정밀도가 19.37%로 2.67% 향상되었으며, t-검증을 통해 유의미한 성능 향상이 있음을 입증하였다.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2000년도 The 7th International Symposium
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• pp.114-115
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• 2000

Aralia elata is found in mountain areas all over Korean peninsula. Aralia elata is the scientific name for Japanese angelica tree. The tree belongs to the family Araliaceae, commonly known as ginseng family. Bud sprouts from apical shoot tip of the plants are rich in flavor and thus mainly used for both folk medicine and vegetable. The stalks with apical buds are gathered in the early spring and planted in sandy soil or water in the greenhouse. The sprouting buds are then collected and sold as fresh vegetable. Although the plants have been used for food, they have been cultivated in a very small scale. In spring, local farmers just go around mountain areas to search the trees and gather the stalks as much as they get and sell them to the market. No conservation efforts have been made to stop the exploitation or to save the dwindling population. We tried to provide local farmers with the plants that may be used as an alternative to stalks from wild populations. This will bel! p conserve the wild populations. However, it is hard to propagate them either by conventional cuttings or by seed germination in a short period of time. Mass propagation using tissue culture systems have shown a great promise with several woody plants. Recently we developed a mass propagation technique via somatic embryogenesis system using mature and/or juvenile explants for Aralia elata. Several factors affecting somatic embryogenesis system including SE(somatic embryo) induction, embryogenic callus proliferation, SE germination, plant regeneration and transplanting to field frill be presented. And some problems arising for the somatic embryogenesis system will be also discussed.