• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.3
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• pp.240-244
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• 1993

Yacon(Polymina sonchifolia POEPP), an indigenous Andean natural resource food plant, was imported as a new root crop from New Zealand in 1986. However the chemical composition and planting system of it have not been research in Korea. The experimental results for the optimum planting densities and mulching effect are as follows. Height of the main stem of yacon was grown linear from July to October, is showed more fast growth as density increased, and showed highest in 70 ${\times}$ 55cm density. The tiller was bubed 3 month after planting but there was no significant difference among mulching, non-mulching condition and planting density. The fresh weight of root of mulching condition was heavier than that in non-mulching condition and 70 ${\times}$ 40cm mulching condition. In mulching treatment, number of roots in dense planting were more than that in sparse planting. The effect of mulching was not shown significantly in root diameter and root length.

• Korean Journal of Plant Resources
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• v.16 no.2
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• pp.118-122
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• 2003

These studies were carried out to clarify the effects of black P.E. mulching and planting density on the growth and rhizome yield of Jihwang #1, a new high yielding Rehmannia glutinosa variety. Emergence ratio was higher 3.1％ in mulching than in non-mulching, but was not affected by planting density. Plant height and fresh leaf weight per plant were increased by mulching and at lower planting density. However, the fresh leaf weight per unit area was increased at higher planting density. Dry rhizome weight was increased 28% in mulching than that of non-mulching. Dry rhizome weight per plant was increased, but that of per unit area was decreased at lower planting density.

• Korean Journal of Plant Resources
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• v.19 no.2
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• pp.374-380
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• 2006

With the aim of inducing mutation in fern Cyrtomium caryoptideum var. coreanum, rhizome segments of In vitro-grown cultures were treated with chemical mutagens such as EMS, NMU and colchicine. Based on regeneration ratios, sensitivities for each treatments were assessed and also optimum treatment condition of each mutagens was explored. Optimum concentration for EMS treatment was considered to be 20 to 50mM and for NMU 5 to 10mM. NMU was found to be more effective in inducing chlorophyll and morphological variations than EMS. The RAPD were performed to check the genetic modification of phenotypical variants. As a result, polymorphic DNA band patterns between wild type and variants were observed by two 10-mer primers.

• Korean Journal of Plant Taxonomy
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• v.46 no.3
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• pp.306-313
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• 2016

A new variety, Hosta clausa Nakai var. geumgangensis M. Kim & H. Jo, was found in Geumgang River in Korea. This variety shares several characteristics (rhizomes with underground stolon, smooth scape and purple-colored anthers) with the $re{\acute{o}}lated$ varieties H. clausa Nakai var. clausa and H. clausa var. normalis F. Maekawa. However, H. clausa var. normalis has open flowers, capsules with seeds, purple-spotted petioles, long pistils, and long narrow perianth tubes, whereas this new variety has open flowers, seedless capsules, green-colored petioles, short pistils, and short narrow perianth tubes. Hosta clausa Nakai var. clausa has closed flowers and seedless capsules.

• Korean Journal of Pharmacognosy
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• v.13 no.4
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• pp.145-152
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• 1982

Three species of genus Polygonum, namely P. cuspidatum, P. sachalinense and P. ellipticum are distributed in Korea. Polygonum ellipticum Migo is a perennial herb in Polygonaceous plants. The root of the plant (Polygoni Rhizoma, 'Ho-jang') have been used as laxative, diuretic and for the treatment suppurative dermatitis in the oriental medicine. As the part of the study for the comparison of the three species in their components, the authors attempted to isolate the anthraquinones and stilbene derivative from the rhizome of P. ellipticum. The methanolic extract of dried rhizome of this plant was fractionated into ether soluble and insoluble fraction and each fraction was applied to column chromatography to isolate above mentioned components. Anthraquinone derivatives were isolated first; comp. I, mp $204{\sim}205^{\circ}$ (physcion), comp. II, mp $254{\sim}255^{\circ}$ (emodin), comp. IV, mp $191{\sim}192^{\circ}$ $(emodin-8-O-{\beta}-D-glucoside)$ and comp. III, mp $280{\sim}282^{\circ}$ $({\beta}-sitosterol-glucoside)$. They were identified by chemical properties and UV, IR and NMR spectra and by the direct comparison with authentic samples. Stilbene derivative was isolated secondly; comp. V, mp $255{\sim}256^{\circ}$ which was reported to possess antibacterial and antifungal activities.

• Korean Journal of Optics and Photonics
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• v.18 no.6
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• pp.421-425
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• 2007

A new 3D rear projection display system using double-layer polarization-selective screen systems, one stacked in front of the other, has been developed. The front and rear screens are made of scattering polarizer films, and they either diffuse-scatter or transmit the incident light depending on the polarization state of the light. The near and for images are projected onto the front and rear screens, respectively, using light waves with mutually orthogonal polarization states. The new display system produces clear high-resolution images, which are visible over a wide range of viewing angle. It was found that the impression of depth is pronounced and eyestrain is only comparable to that by 2D display systems.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.1
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• pp.80-86
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• 1998

This work was designed to determine the optimum roasting conditions with application of a pressure roaster for improving the roasting process of the Polygonatum sibiricum tea which has been roasting with a traditional method. Soluble solid content of the Polygonatum cibiricum tea was 63.16% in the tea roasted at 0.85kgf/$\textrm{cm}^2$(roasting pressure) and 13.9min(roasting time) which were maximum point by the ridge analysis. The optimum conditions predicted for each corresponding sensory properties of the Polygonatum cibirium tea were 0.87kgf/$\textrm{cm}^2$ and 9.2min in color, 0.89kgf/$\textrm{cm}^2$ and 9.7min in sweet 0.72kgf/$\textrm{cm}^2$ and 5.4min in burnt flavor, 0.89kgf/$\textrm{cm}^2$ and 9.9min in appetizing flavor, 0.87kgf/$\textrm{cm}^2$ and 9.3min in aftertaste, 0.89kgf/$\textrm{cm}^2$ and 10.0min in aroma, and 0.88kgf/$\textrm{cm}^2$ and 9.6min in overall acceptability of the tea. The optimum conditions based on the soluble solid content and sensory properties of the Polygonatum cibiricum tea, were 0.83~0.88kgf/$\textrm{cm}^2$ and 9.7~10.4min.

• YAKHAK HOEJI
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• v.36 no.5
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• pp.474-480
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• 1992

Astilbes rhizoma has been used for headache, arthralgia, chronic bronchitis and stomachalgia in traditional chinese medicine. The analgesic activities and their components of Astilbe chinensis var. davidii Rhizomes were evaluated. The ether and ethylacetate fractions of 70% EtOH extract showed considerable analgesic activities by acetic acid induced writhing method. Compound $1{\sim}5$ were isolated from ethylacetate fraction and identified as gallic acid, (+)-catechin, (+)-gallocatechin, bergenin and 11-O-galloylbergenin on the basis of spectroscopic methods. Among them (+)-gallocatechin showed stronger analgesic activity than that of other compounds.

• Journal of the Korean Institute of Landscape Architecture
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• v.29 no.2
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• pp.50-60
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• 2001

교량설계에 있어서는 교량의 기능과 안전성, 경제성 등 구조 광학적인 면을 고려하여 설계하게 되는데 최근에는 교량의 경관설계에 관해서도 많은 관심을 갖고 있다. 그러나, 국내에선 교량의 구조적인 측면에서의 연구는 활발하게 이루어지고 있으나 교량의 경관설계에 대한 연구는 거의 이루어지고 있지 않다. 따라서, 본 연구의 목적은 교량의 구조 공학적인 판단과 경관 공학적인 판단에 의해서 교량 형식을 결정하는 방법과 선호도가 높은 현수교의 시점장을 분석하는데 있다. 교량형식을 결정하는 방법은 기초설계단계에서 Seen 경관을 고려하여 교량의 유형을 결정하고, 교량의 구조적인 정.동역학적 검토와 Seen경관.Sequence 경관 등을 고려하여 교종의 형식을 결정하게 되는 각 단계별 설계조건에 따른 교량설계 방법을 흐름도로 제시하였다. 또한, 현수교의 시점장의 범위를 정량적으로 나타내기 위해서 교량전체에 대한 시선입사각, 가까운 쪽의 주탑에 대한 시선입사각, 가까운 쪽 주탑의 외관 크기에 대한 연직시각, 교량전체가 시야에 들어올 수 있는 수평시각 등을 주시실험 자료와 Professional 현수교의 사진에 의한 구조형태의 비율 등을 측정하여 분석 교차한 결과 교량전체에 대한 시선입사각 $\alpha$=(15$\pm$7.5)$^{\circ}$, 가까운 쪽의 주탑에 대한 시선입사각 V=(30$\pm$7.5)$^{\circ}$, 가까운 쪽 주탑의 외관 크기에 대한 연직시각 18$^{\circ}$$\leq$$\delta$27$^{\circ}$, 교량전체가 시야에 들어올 수 있는 수평시각 $\theta$$\leq$60$^{\circ}$의 시점장을 얻을 수 있었다.

• Proceedings of the Korea Water Resources Association Conference
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• 2010.05a
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• pp.1956-1960
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• 2010

최근 이상홍수 및 하천정비 등으로 인해 갈수시 또는 홍수시 하천 모니터링을 위한 기초자료로 유량측정의 필요성이 부각되고 있다. 기존 유량측정 방법은 고비용과 다수의 측정인력이 필요하기 때문에 이를 개선하기 위하여 최근 전자장비를 이용한 비접촉식 유량측정에 대한 연구가 다수 진행 중에 있다. 이 중 간편하고 측정 정확도를 유지할 수 있는 표면영상유속계(SIV, Surface Image Velocimetry)에 대한 연구가 국내외에서 다양하게 이루어지고 있다. 표면영상유속계는 일정 시간 간격을 갖는 두 영상을 분석하여 유속을 계산하기 때문에 수표면이 움직이는 시간보다 두 영상 사이의 시간 간격을 길게 할 경우 잘못된 상관영역을 찾게 되어 유속 측정의 정확도를 떨어뜨릴 수 있다. 이러한 문제점을 개선하기 위해서 영상간의 시간간격 변화에 따른 표면영상유속계의 정확도 분석을 수행하였다. 본 연구에서는 영상간의 시간간격에 따른 표면영상유속계의 정확도 분석을 위해 현장에서 수면 요철이 발생하는 근경 영상을 이용하여 영상내의 수면 움직임의 최소 지속시간을 측정하였다. 측정 결과 대부분의 수면 요철은 0.1 ~ 0.2 초 내에서 발생하였다. 측정 결과 일반 캠코더를 이용하여 초당 최대 30장의 영상을 이용하여 하천 표면유속을 측정한다면 문제가 없을 것으로 판단된다.