• 한국분말재료학회지
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• 제20권2호
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• pp.107-113
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• 2013

In this study, the microstructure and valuable metals dissolution properties of PDP waste panel powders were investigated as a function of milling parameters such as ball diameter size, milling time, and rotational speed during high-energy milling process. The complete refinement of powder could achieved at the ball diameter size of 5 mm due to sufficient impact energy and the number of collisions. With increasing milling time, the average particle size was rapidly decreased until the first 30 seconds, then decreased gradually about $3{\mu}m$ at 3 minutes and finally, increased with presence of agglomerated particles of $35{\mu}m$ at 5 minutes. Although there was no significant difference on the size of the particle according to the rotational speed from 900 to 1,100 rpm, the total valuable metals dissolution amount was most excellent at 1,100 rpm. As a result, the best milling conditions for maximum dissolving amount of valuable metals (Mg: 375 ppm, Ag 135 ppm, In: 17 ppm) in this research were achieved with 5 mm of ball diameter size, 3min of milling time, and 1,100 rpm of rotational speed.

• 한국분말재료학회지
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• 제17권2호
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• pp.88-100
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• 2010

• 한국자원식물학회지
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• 제34권6호
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• pp.633-660
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• 2021

This study was carried out to elucidate the distribution of vascular plants and their usefulness of Mt. Munsusan (1,205 m) in Bonghwa County, North Gyeongsang Province, South Korea. The vascular plants that were investigated in 2 years (2019 ~ 2020) with 15 times consisted a total of 571 taxa; 94 families, 310 genera, 496 species, 4 subspecies, 63 varieties and 8 formas. For the Korean endemic plants, 17 taxa were recorded and 3 taxa of Vulnerable Species (VU) and 9 taxa of Least Concerned species (LC) categorized by the Korean Forest Service as rare plants were investigated in this region. Furthermore, IV, III degrees of floristic regional indicator plants designated by the Korean Ministry of Environment included 8 taxa and 27 taxa, respectively. Among them, edible, medicinal, ornamental, feed/composting, industrial plants were 391 taxa, 359 taxa, 301 taxa, 241 taxa, 217 taxa, respectively. In addition, 25 taxa of naturalized plants were observed.

• 한국자원식물학회지
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• 제22권2호
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• pp.180-194
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• 2009

본 조사지역의 관속식물은 121과 399속 510종 67변종 7품종 2아종 및 2교잡종 등 59 식재종을 포함하여 588종류로 조사되었으며. 이 중 116종은 금번 조사에서 새로이 추가되었다. 경부고속철도가 통과하는 지역인 무제치 3, 4, 5, 6늪과 대성사 주위의 습지와 천성산일원에서 희귀 및 멸종위기식물은 6종, 한국특산식물은 9종이 발견되었고, 식물구계학적 특정식물은 37종이 발견되었다. 경부고속철도건설로 인하여 나타날 식물상의 변화, 특히 습지의 식물에 미치는 영향을 알아보기 위해서는 사후 장기적인 모니터링이 필요할 것으로 보이며, 고층습지의 수원 변동에 대하여 식물보전계획을 수립해야한다.

• 한국한의학연구원논문집
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• 제14권3호
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• pp.49-56
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• 2008

Glehnia littoralis Fr. Schmidt et Miquel is an important medicinal plants in East Asian countries. This plant species naturally distributed in Korea, Japan, China, and Taiwan, but it is a rare plants living in the coastal dune in Korea. To investigate the genetic variation, genetic diversity and genetic evolutionary relationships of 14 different geographical G. littoralis, ITS sequence and random amplified polymorphic DNA (RAPD) were analyzed. On the basis of ITS sequences, it was clearly showed that the ITS1 and ITS2 sequences among 14 populations are identical regardless of geographical origin excepting 2 bp in pair-wise comparison of ITS1. Furthermore, RAPD results also showed that 14 different geographical G. littoralis produce various polymorphic patterns without critical relationship among neighboring regions. These combined results suggest that the geographical variation and genetic evolution of G. littoralis is stable and provide important information on genetic diversity, and conservation of this rare plant species in situ and ex situ.

• 식물분류학회지
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• 제52권1호
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• pp.24-28
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• 2022

Pteris griffithii Hook., one of the rarest fern species on the Indian subcontinent, is reported from Bhutan for the first time. The identity of this species was confirmed through morphological determination at the National Herbarium (THIM) of the National Biodiversity Centre (NBC) of Bhutan. It was found only in one location, in Gyelpozhing in eastern Bhutan, at an elevation of 521 m a.s.l. on 10 January 2016. Given that a very limited study of this species was conducted, the knowledge baseline with regard to its distribution is poor. It is also reported that this species has not been found for several years. The species is also considered to be very rare or critically endangered in some countries; however, there are no assessments on the International Union for Conservation of Nature (IUCN) Red List for this particular species. This paper attempts to provide baseline information considering its rarity and data deficiency. This species is also reported from the adjacent neighboring Indian state of Arunachal Pradesh as very rare, and also from Myanmar; however, confirmation of its presence in China is not clear at this time. Therefore, considering its data deficient status, we attempt to document it scientifically to create a knowledgebase pertaining to this particular species. Concurrently, this species merits further research to understand its distribution patterns in Bhutan and any related anthropogenic threats.

• 식물분류학회지
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• 제41권3호
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• pp.280-286
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• 2011

The natural habitats and distribution of five rare plants were recently discovered in Korea. Salomonia oblongifolia DC., which grows in mountain wetlands, was found in Gijang-gun, Busan, Gokseong-gun, Jeollanam-do, and Shinan-gun, Jeollanam-do. Glaux maritima var. obtusifolia Fernald, which grows along the coast, was found in Yangyang-gun, Gangwon-do, Pohang-si, Gyeongsangbuk-do and Buk-gu, Ulsan. Tillaea aquatica L. and Limosella aquatica L., which was previously not known to be present in Korea, were discovered in Gijang-gun, Busan for the first time. Apocynum lancifolium Russanov, which has a narrow distribution range in Korea, was also found in Samcheok-si, Gangwon-do, Ansan-si, Gyeonggi-do, Siheung-si, Gyeonggi-do, Jung-gu, Incheon, Yeongdeok-gun, Gyeongsangbuk-do and Shinan-gun, Jeollanam-do.

• Nuclear Engineering and Technology
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• 제49권2호
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• pp.373-379
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• 2017

Seismic probabilistic safety assessments are used to help understand the impact potential seismic events can have on the operation of a nuclear power plant. An important component to seismic probabilistic safety assessment is the seismic hazard curve which shows the frequency of seismic events. However, these hazard curves are estimated assuming a normal distribution of the seismic events. This may not be a strong assumption given the number of recorded events at each source-to-site distance. The use of a normal distribution makes the calculations significantly easier but may underestimate or overestimate the more rare events, which is of concern to nuclear power plants. This paper shows a preliminary exploration into the effect of using a distribution that perhaps more represents the distribution of events, such as the t-distribution to describe data. The integration of a probability distribution with potentially larger tails basically pushes the hazard curves outward, suggesting a different range of frequencies for use in seismic probabilistic safety assessments. Therefore the use of a more realistic distribution results in an increase in the frequency calculations suggesting rare events are less rare than thought in terms of seismic probabilistic safety assessment. However, the opposite was observed with the ground motion prediction equation considered.

• 한국자원식물학회지
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• 제29권5호
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• pp.604-619
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• 2016

본 연구는 강화도내의 3개 산지인 별립산, 봉천산, 국수산을 대상으로 관속식물을 조사하기 위해 수행되었다. 현지조사는 2015년 3월부터 10월까지 총 6회 실시한 결과, 관속식물은 총 93과 280속 392종 4아종 53변종 6품종이 확인되었다. 이 중 산림청 지정 희귀식물 3분류군, 특산식물 6분류군, 식물구계학적 특정식물 Ⅴ등급 1분류군, Ⅳ등급 4분류군, Ⅲ등급 8분류군으로 각각 확인되었다. 귀화식물은 29분류군이 확인되었으며, 귀화율 6.4%, 도시화지수 9%로 각각 나타났다. 본 연구에서 확인된 관속식물 455분류군을 유용도에 따라 구분하면 식용 203분류군(44.6%), 목초용 178분류군(39.1%), 약용 157분류군(34.5%), 관상용 50분류군(11%), 목재용 17분류군(3.7%), 염료용 10분류군(2.2%), 섬유용 3분류군(0.7%), 공업용 4분류군(0.9%)의 순으로 나타났고, 용도를 알지 못하는 식물은 88분류군(19.3%)으로 나타났다.

• 한국환경복원기술학회지
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• 제22권2호
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• pp.31-48
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• 2019

The purpose of this study is to present the basic data for establishing the plan of usage and management of healing forest by surveying and analysing the vascular plants distributed in Jangseong Healing Forest. The numbers of vascular plants were summarized as 338 taxa including 85 families, 211 genera, 294 species, 3 subspecies, 33 varieties and 8 forms. In the result of life form, hemicryptophytes and geophytes were the most common and hydrophytes were the least. The rare plants were 5 taxa including Abies koreana Wilson(planted), Thuja orientalis L.(planted), Scutellaria insignis Nakai, Tricyrtis macropoda Miq. and Arisaema heterophyllum Blume. The Korean endemic plants were 12 taxa including Philadelphus schrenkii Rupr., Indigofera koreana Ohwi, Lycoris flavescens M.Y.Kim ＆ S.T.Lee and so forth. The specific plants by floristic region were 28 taxa including 2 taxa of grade IV, 3 taxa of grade III, 7 taxa of grade II and 16 taxa of grade I. The naturalized plants were 20 taxa including Fallopia convolvulus (L.) $A.L{\ddot{o}}ve$, Ailanthus altissima (Mill.) Swingle, Veronica arvensis L., Poa pratensis L. and so forth. The invasive alien plants were Rumex acetocella L. and Ambrosia artemisiifolia L..