• 식물분류학회지
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• 제50권4호
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• pp.403-412
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• 2020

Colonies of three independent gametophytes (one that is filamentous and two that are ribbon-like) without sporophytes occur in Gyeonggi-do, Gangwon-do, Gyeongsang-do, and Jeju-do, Korea. They have a moss-like appearance at first sight, with tiny plantlets and gemmae, and grow in cool, shaded, relatively deep dint places of large rocks, such as the small caves in high mountains, close to valleys. The gametophytes were identified based on morphological and molecular data by chloroplast DNA (cpDNA) sequence data (rbcL, rps4 gene and rps4-trnS intergenic spacer). Here, rbcL, rps4 gene and rps4-trnS intergenic spacer data of one independent gametophyte distributed in Korea have the same morphology, DNA sequence and monophyletic group as Crepidomanes intricatum from the eastern United States. They also share the same cpDNA data with Crepidomanes schmidtianum recently reported from Korea. The other independent gametophyte should be Hymenophyllum wrightii based on cpDNA data. The last one was presumed to be Pleurosoriopsis makinoi based on molecular data. The taxonomic status was confirmed to be the forma of Hymenophyllum wrightii through a revision of Hymenophyllum wrightii f. serratum based on molecular data.

• 새물리
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• 제68권11호
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• pp.1215-1224
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• 2018

Most solar photovoltaic (PV) modules frequently get shadowed, completely or partially, resulting in a reduction of PV generation. This paper presents and compares the results from simulations and experimental measurements of the power output from a single PV module under various shading conditions. The study was carried out with a 90 W PV module and a 250 W PV module. The shaded area was increased from 0 to 100% for both variable and constant irradiances to analyze the effect of fluctuations in the solar irradiance certain shading conditions. The effect of shading for irradiance levels from 100 to $900W/m^2$ was investigated. Results showed that for every $100W/m^2$ decrease in the solar irradiance level, the power output decreased by 9, 0.7 and 1.5 W at 0, 25 and 50% shading, respectively. For solar irradiance levels higher than $500W/m^2$, the temperature increased by 1.6, 2.7 and $1.1^{\circ}C$ at 0, 25 and 50% shading, respectively, for every $100W/m^2$ increase in the irradiance.

• Journal of Plant Biotechnology
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• 제2권1호
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• pp.43-49
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• 2000

An efficient and reliable Agrobacterium transformation procedure based on TDZ (thidiazuron)-induced organogenesis was established and applied to six Brazilian eggp1ant varieties. Optimum transgenic plants recovery was achieved upon the study of the following parameters affecting transformation efficiency, using F-100 variety as a model: i) explant source; ii) pre-culture period; iii) physical state of the pre-culture medium and iv) coculture conditions. The highest frequency of kanamycin-resistant calli derived from leaf explants (5%) was obtained without a pre-culture period and co-cultivation for 24 h in liquid medium followed by five days on solid RM (regeneration medium). For cotyledon explants, best results were achieved upon a pre-culture of 24 h in liquid RM and a co-cultivation period of 24 h in liquid RM followed by three days in solid RM, resulting in a transformation Sequency of 22.7%. Kanamycin-resistant organogenic calli were also obtained from cultivars Emb, Preta Comprida, Round nose Shaded, Campineira and Florida Market. The expression pattern of an epidermis-specific promoter was studied using transformants expressing a chimaeric construct comprised by the promoter Atgrp-5 transcriptionally fused to the coding region of the gus gene. The expression pattern was similar to that previously observed in tobacco and Arabidopsis thaliana, with preferential expression at the epidermis and the stem phloem. These results support the idea that the Atgrp-5 promoter can be used to drive defense genes in these tissues, which are sites of pathogen interaction and spread, in programs for the genetic improvement of eggplant.

• Journal of Korean Neurosurgical Society
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• 제30권6호
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• pp.711-716
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• 2001

Objectives : Three-dimensional computed tomographic angiography(3D-CTA) is recently developed diagnostic imaging modality. We have studied this noninvasive method for possible role in replacing conventional angiography( CA) in the detection of aneurysms of the circle of Willis in patients with subarachnoid hemorrahge(SAH). Methods : We studied retrospectively, the 100 patients with SAH or unruptured aneurysms admitted to our hospital from October 1997 to December 1998. Among there, 85 patients underwent CTA, 82 patients underwent CA and 67 patients underwent both of CTA and CA. 3D-CTA was obtained using maximum intensity projection(MIP) and shaded-surface display(SSD) reconstruction. Results : Total 107 aneurysms were detected in 92 patients, and 64 aneurysms were detected in 67 patients underwent both CTA and CA. In five cases of those 67 cases, aneurysms were detected by CA but not by 3D-CTA. The detection rate of aneurysms(91.8%) and the detection rate of parent artery in cases of anterior communicating artery aneurysms(86.9%) with total 3D-CTA were relatively compatible with that of CA. But 3D-CTA was not enough in detection of posterior communicating artery aneurysms, internal carotid artery aneurysms as well as small sized aneurysm(<3mm). Conclusion : We consider CTA is valuable in as a screening test for cerebral aneurysm and follow-up test. And it is also valuable in early surgery for patients with aneurysmal rebleeding because of simple, quick, non-invasive method.

• 한국버섯학회지
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• 제14권3호
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• pp.105-110
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• 2016

산느타리버섯의 원목재배 시험결과 플라스틱 콘테이너 상자($50cm{\times}35cm{\times}30cm$)내에 토양매립하였을 경우 '향산' 품종에서는 원목당 수량이 340 g 정도로 톱밥종균 접종과 액체종균 접종에서 큰 차이가 없었고, '호산' 품종에서는 톱밥종균 접종이 원목당 450 g으로 수량이 높았으나 액체종균 접종은 259 g으로 낮게 나타났다. 원목을 비가림하우스내 토양에 매립하였을 경우 미루나무에 비해 가중나무의 수량이 높게 나타났고, 품종에 있어서는 '향산' 품종보다 '호산' 품종의 수량이 더 높게 나타났다. 산느타리버섯의 적정 수종 선발시험에서는 버드나무와 벚나무가 '호산' 품종 및 '향산' 품종 모두에서 수량이 높게 나타났다.

• 전력전자학회논문지
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• 제21권4호
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• pp.335-342
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• 2016

This paper proposes an energy storage-assisted, series-connected module-integrated power conversion system that integrates a photovoltaic power conditioner and a charge balancing circuit. In conventional methods, a photovoltaic power conditioner and a cell-balancing circuit are needed for photovoltaic systems with energy storage devices, but they cause a complex configuration and high cost. Moreover, an imbalanced output voltage of the module-integrated converter for PV panels can be a result of partial shading. Partial shading can lead to the fault condition of the boost converter in shaded modules and high voltage stresses on the devices in other modules. To overcome these problems, a bidirectional buck-boost converter with an integrated magnetic device operating for a charge-balancing circuit is proposed. The proposed circuit has multiple secondary rectifiers with inductors sharing a single magnetic core, which works as an inductor for the main bidirectional charger/discharger of the energy storage. The secondary rectifiers operate as a cell-balancing circuit for both energy storage and the series-connected multiple outputs of the module-integrated converter. The operating principle of the cell-balancing power conversion circuit and the power stage design are presented and validated by PSIM simulation for analysis. A hardware prototype with equivalent photovoltaic modules is implemented for verification. The results verify that the modularized photovoltaic power conversion system in the output series with an energy storage successfully works with the proposed low-cost bidirectional buck-boost converter comprising a single magnetic device.

• 한국조경학회지
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• 제15권2호
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• pp.139-148
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• 1987

Exochorda serratifolia, broad-leaved shrub has beautiful flowers and is resistant to cold, shade and decease. New this native plant is considered to be worth being exploited as the outstanding plant for landscaping and horticulture. So this study was executed to utilize Exochorda serratifolia as the planting material for landscaping and horticulture through the survey of its habitat environment and the experimennt of its seed physiology and germination, vegetative propagation, culture and utilization, etc.. The results are as follows ; 1. The color of the flower is white, blooming in the early and middle of May and the seeds ripen late in Sep.. 2. The elevation, elevation, gradient and direction of the native habitat were 250m, 20-25$^{\circ}$and northern side respectively. 3. The soil pH of the natural habitat was 5.3 and soil fertility was poor. 4. Exochorda serratifolia appeared as indicator within P. densiflora community and its neighboring species were Q. mongolica, Q. dentata, R. mucronulatum, L. obtusiloba, E. oxyphillus, C. heterolphylla, var thunbergii, etc.. 5. The optimum temperature for seed germination was found at 20$^{\circ}C$ and the longer the stratification period at 5$^{\circ}C$ was, the lower the germination rate was. 6. The treat merits of GA and Kinetin increased the seed germination rate, especially under the dark condition but their high concentrations decreased the seed germination rate. 7. The rooted rate of the greenwood cutting was the highest at IBA 100ppm plot of vermiculite bed but its high concentration decreased the rooted rate conspicuously. 8. In the tissue culture, the each 1.0 ppd plot of NAA, Kinetin and NAA 1.0ppm + Kinetin showed the best growth. And the mixture of NAA 1.0ppm and Kinetin showed better growth than the single treatment of NAA or Kinetin did. 9. Transplanted Exochorda serratifolia showed healthy growth with shaded environmental condition(42.1% light intensity), therefore they can be cultivated as a shade tolerant landscape plant. 10. It was considered that Exochorda serratifolia was applicable to group planting at shade places or under trees in parks, homes, etc..

• 한국의학물리학회지:의학물리
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• 제17권3호
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• pp.167-172
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• 2006

전산화단층촬영에서 조영 증강을 위한 조영제 주입은 정맥내에 삽입한 카테터를 통해 자동주입기로 주입하고 있다. 정맥내에 위치한 카테터를 제거하는 도중에 IV 카테터가 부러져 정맥내에 남아 있는 카테터의 조각은 환자에게 순환기 질환의 위험을 초래할 수 있다. CT 검사 중에 정맥내에 카테터 조각이 남아있는 2명의 환자를 대상으로 카테터의 크기 및 위치를 정확히 확인하기 위해 MDCT를 이용하여 정맥내 주사부위를 스캔하였다. 3D 재구성은 MPR, MIP, 볼륨렌더링, SSD 등으로 구성하였다. 정맥내에 위치한 카테터 조각을 MDCT로 스캔한 데이터를 3D 재구성으로 정맥내의 위치 및 크기를 확인하였고, 카테터 조각을 제거하는데 일조하였다.

• 한국전자통신학회논문지
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• 제13권3호
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• pp.539-546
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• 2018

최근 태양광발전시장이 급격히 증가하면서 태양전지 모듈 출력 최소화를 위한 연구에 관심이 집중되고 있다. 태양광 발전에서 부정합이 발생하면 옵티마이저의 역할이 중요하다. 기존의 시스템에서는 중앙 집중형 인버터 방식과 직렬형 마이크로인버터방식을 주로 사용되고 있다. 본 논문에서는 기존의 시스템 구성방식과 부정합으로 인한 발전효율 손실 문제를 분석하였다. 또한 음영으로 인한 부정합이 발생하게 되면 이를 개선할 수 있는 모듈 부착형 전력보상방식을 제안하였다. 제안한 모듈 부착형 옵티마이저를 구현하여 기존의 운영방식과 비교, 분석한 결과 제안한 운영방식의 효율이 크게 향상됨을 확인하였다.

• 생약학회지
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• 제38권2호통권149호
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• pp.157-163
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• 2007

Trillium tschonoskii Maxim. is a kind of 64 endangered plant species designated by the Ministry of Environment in Korea. It is very a rare native plant throughout the country. Therefore, this study was conducted to investigate the native T. tschonoskii in Ulleung Island for their distribution and ecological characteristics. They were mostly distributed valley, mid-slope of the mountain from 186 to 458 m altitude. They had a little low light conditions as they faced west, north west, south west, south-south west, north-north east and east-east north. They were provided with slightly humid condition. Aerial humidities of these quadrates were variable as 21.5-71%. They were located on the variable slopes of 5 to 43 degrees. Soil humidity was slightly dry. Native sites were semi-shaded because tree layer such as Tilia insularis, Zelkova serrata, okamotoanum etc.and sub-tall tree layer such as Ligustrum foliosum, Comellia japonica, Tilia insularis, Callicarpa japonica and so on were grown near by. Woody plants such as A. Okamotoanum, Sorbus commixta, Fagus japonica var. multinervis etc. were frequently observed. These environmental conditions were suitable that T. tschonoskii grows up naturally because of high Percentage as 52.78% of blooming individuals in this study. These native sites were classified with three communities, T. tschonoskii-Majanthemum dilatatum community, T. tschonoskii-Anthriscus sylvestris community and T. tschonoskii-Hepatica maxima community in accordance with altitude and aerial humidity. The best way ffr the preservation of T. tschonoskii habitats and maintainance of its recent population is maintained in recent environmental condition and ecological condition without any management by human-being.