• Title/Summary/Keyword: Plant specimens

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Taxonomic revision of the Artemisia sacrorum group (더위지기 및 근연분류군의 분류학적 재검토)

  • Park, Myung Soon;Nam, Bo Mi;Chung, Gyu Young
    • Korean Journal of Plant Taxonomy
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    • v.46 no.2
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    • pp.175-186
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    • 2016
  • The taxonomic status and scientific names of Artemisia gmelinii and its allied taxa have long been debated. To provide correct names and taxonomic status, A. gmelinii and its allied taxa were reviewed in this study based on morphological characters. After a comparison of original descriptions and type specimens, the names of A. freyniana f. discolor and A. freyniana f. vestita used in Korea were recognized as A. sacrorum var. sacrorum and A. sacrorum var. incana, respectively, based on the characters of the trichome on the leaf, the geographical distributions, the chromosome numbers, and the existence of a pinule connection on the exine of the pollen. A. iwayomogi, the scientific name misused as A. gmelinii, was combined and newly named A. sacrorum var. iwayomogi (Kitam.) M. S. Park & G. Y. Chung based on its morphological similarity to the A. sacrorum group. A description, illustration, and key for each of the taxa are provided here.

Reexamination on foreign collectors' sites and exploration routes in Korea (II) - with respect to T. Nakai - (외국인의 한반도 식물 채집행적과 지명 재고(II): Takenoshin Nakai (中井益之進))

  • Kim, Hui;Chang, Gae-Sun;Chang, Chin-Sung;Choi, Byoung-Hee
    • Korean Journal of Plant Taxonomy
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    • v.36 no.3
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    • pp.227-255
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    • 2006
  • Takenoshin Nakai (1882-1952), Japanese taxonomist and professor of the University of Tokyo, who was one of Korean flora specialists, conducted his plant exploration from 1909 to 1942 after he completed two volumes of Flora Koreana. His collections, which are currently deposited at the University of Tokyo herbarium (TI), are important research resources. Since all collection sites were simply described in his collection sites in Romanized characters based on Japanese pronunciation, it is difficult for Korean as well as Japanese botanists to pinpoint those sites using the current or the old Korean maps. No single literature has been available regarding his collection routes and sites, although this information is essential to current plant systematic research in Korea. From this current study, all locality names were reviewed based on his own collections as well as his written literatures, and those were listed as the order of his collection dates with seven maps here.

Vascular Plants of Mt. Manhobong in Mt. Tohamsan District, Gyeongju National Park (경주국립공원 토함산지구 내 만호봉 일대의 관속식물상)

  • You, Ju Han;Kwon, Soon Young
    • Korean Journal of Plant Resources
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    • v.31 no.5
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    • pp.575-589
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    • 2018
  • The purpose of this study is to provide the baseline data for conservation and management of the ecosystem of Gyeongju National Park by surveying and analysing the vascular plants distributed in Mt. Manhongbong (522 m). The vascular plants were surveyed form May 2012 to August 2017. The vascular plants on this site was classified as follow. Based on voucher specimens, the vascular plants of this site consisted of 91 families, 292 genera, 397 species, 4 subspecies, 48 varieties and 8 forms. The 2 taxa of threatened species, 11 taxa of rare plants and 14 taxa of Korean endemic plants were investigated. The specific plants by floristic region were totally 39 taxa, which were 3 taxa of grade V, 5 taxa of grade IV, 2 taxa of grade III, 11 taxa of grade II and 18 taxa of grade I. The naturalized plants were identified as 33 taxa and the percentage of naturalized index (NI) was 7.2%, and urbanized index (UI) was 10.3%, respectively. The invasive alien plants were 2 taxa, such as Ambrosia artemisiifolia L. and Aster pilosus Willd.

Preparation and characteristics of modified Ni/YSZ cermet for high temperature electrolysis (고온 수전해 전극용 modified Ni/YSZ cermet 제조 및 전극특성)

  • Chae, Ui-Seok;Park, Geun-Man;Hong, Hyeon-Seon;Choo, Soo-Tae;Yun, Yongseung
    • Transactions of the Korean hydrogen and new energy society
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    • v.15 no.2
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    • pp.98-107
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    • 2004
  • Modified Ni/YSZ cermets for high temperature electrolysis were synthesized by dry or wet mechanical alloying methods. The Ni/YSZ composit particle was directly fabricated from the ball milling of Ni and YSZ powder or obtained from the reduction of NiO/YSZ particle after the ball milling of NiO and YSZ. In the case of the NiO/YSZ composite particle, the dry milling increased the average particle size whereas the wet milling decreased the size. The dry milling showed that fine YSZ particles were distributed over large Ni surfaces while Ni and YSZ particles similar in size were well mixed in the wet milling method. These features were the same in the Ni/YSZ composite particle prepared from Ni and YSZ powders. The electrical conductivity of the wet-milled Ni/YSZ cermet showed the highest value of $2{\times}10^2S/cm$ among the specimens and this value was increased to $1.4\times10^4S/cm$ after the sintering at $900^\circ{C}$ for 1 h.

Procedure and Method of Equipment Qualification for Solenoid-Operated Valves Used in Nuclear Power Plants (원전용 솔레노이드 밸브의 기기검증 절차 및 방법)

  • Lim, Byung-Ju;Park, Chang-Dae;Chung, Kyung-Yul
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.35 no.6
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    • pp.683-691
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    • 2011
  • In order to develop technology for an equipment qualification (EQ) test, which is an important process in localizing solenoid-operated valves used in nuclear power plants, we analyzed related regulations, test procedures, conditions, equipment, and acceptance criteria. EQ regulations for the solenoid-operated valve are classified as law, guide, and standard, and are subdivided according to test specimens and contents. The EQ test is composed of functional, normal-, and accident- condition tests. The solenoid-operated valve is aged under normal and accident conditions, which are predicted in the design conditions of a nuclear power plant, and the performance of the valve is measured by a functional test. The test method and procedure analyzed in this paper might be very useful for manufacturers as well as EQ testers.

Reexamination on foreign collectors' sites and exploration routes in Korea - with respect to U. Faurie - (외국인의 한반도 식물 채집행적과 지명 재고: Urbain Faurie)

  • Chang, Chin-Sung;Choi, Byoung-Hee;Kim, Hui;Lee, Ji-Yeon
    • Korean Journal of Plant Taxonomy
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    • v.34 no.2
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    • pp.87-96
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    • 2004
  • Father, U. Faurie visited Korea (Busan, Incheon, Nampo, Pyongyang, Seoul, Wonsan, Mt. Geumgang of Gangwon-do, and Jeju-do) three times for his plant collections (1901, 1906, and 1907). During his plant explorations, Faurie collected many specimens which were investigated and studied by T. Nakai and H. L$\acute{e}$veill$\acute{e}$ later. Unfortunately all collection sites were simply described in his collection sites in Romanized character, so that it is difficult to pinpoint those sites using the current or old Korean map. From this study, many locality names were reviewed based on his own collections and literatures, and those were listed as the order of his collection dates.

The Classification of U.T Defects in the Pressure Vessel Weld using the Pattern Recognition Analysis (형상인식을 이용한 압력용기 용접부 결함 특성 분류)

  • Shim, C.M.;Joo, Y.S.;Hong, S.S.;Jang, K.O.
    • Journal of the Korean Society for Nondestructive Testing
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    • v.13 no.2
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    • pp.11-19
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    • 1993
  • It is very essential to get the accurate classification of defects in primary pressure vessel weld for the safety of nuclear power plant. The signal analysis using the digital signal processing and pattern recognition is performed to classify UT defects extracting feature vector from ultrasonic signals. The minimum distance classifier and the maximum likelihood classifier based on statistics were applied in this experiment to discriminate ultrasonics data obtained form both the training specimens (slit, hole) and the testing specimens(crack, slag). The classification rate was measured using pattern classifier. Results of this study show the promise in solving the many flaw classification problems that exist today.

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Evaluation of Vacuum Brazed WC and Stainless Steel for Oil Sands Plant (오일샌드 플랜트용 초경합금과 스테인레스강의 진공브레이징 특성평가)

  • Chang, Se-Hun;Cho, Seung-Hyun;Ahn, Seong-Woo;Heo, Joong-Sik;Kim, In-Pyo;Oh, Ik-Hyun
    • The KSFM Journal of Fluid Machinery
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    • v.19 no.3
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    • pp.48-52
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    • 2016
  • Microstructure and tensile strength of the vacuum brazed stainless steel(STS304) and WC-8 %Co were investigated. For brazing, the BNi-2, 3(A.W.S standard) were used as filler metals. It was found that metallic compounds of W-Ni were observed at the between WC metrix and brazed layer. Among these filler metals, the BNi-2 showed excellent wettability, but tensile strength was lower than BNi-3. The fracture of the brazed specimens with BNi-2 was occurred at the between WC metrix and brazed layer. The fracture of the brazed specimens with BNi-3 was occurred at the between WC metrix and brazed layer, and between brazed layer and stainless steel.

Molecular Taxonomical Re-classification of the Genus Suillus Micheli ex S. F. Gray in South Korea

  • Min, Young Ju;Park, Myung Soo;Fong, Jonathan J.;Seok, Soon Ja;Han, Sang-Kuk;Lim, Young Woon
    • Mycobiology
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    • v.42 no.3
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    • pp.221-228
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    • 2014
  • The fungal genus Suillus Micheli ex S. F. Gray plays important roles in the survival and growth of plant seedlings. Humans have utilized these ectomycorrhizal fungi to enhance the nutrient uptake and defense systems of plants, particularly in the reforestation of coniferous forests. The genus Suillus is easily distinguishable by its distinctive morphological features, although the morphology of the fruiting body does not facilitate reliable interspecies discrimination. On the basis of micro-morphological features and internal transcribed spacer sequence analysis, we found that 51 of 117 Korean Suillus specimens had initially been misidentified. The list of the 12 Suillus species previously recorded in Korea was re-evaluated and revised to only eight distinct species: S. americanus, S. bovinus, S. granulatus, S. grevillei, S. luteus, S. pictus, S. placidus, and S. viscidus. We provide taxonomical descriptions for six of these species from the sample specimens.

The Evaluation of Fretting Fatigue Behavior on Rotary Bending Fatigue for Railway Axle Material (회전굽힘 피로 하에서의 철도 차축재료 프레팅 피로거동 평가)

  • Choi, Sung-Jong;Kwon, Jong-Wan
    • Transactions of the Korean Society of Automotive Engineers
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    • v.18 no.2
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    • pp.74-82
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    • 2010
  • Fretting damage can be observed in automobile and railway vehicle, fossil and nuclear power plant, aircraft etc. In the present study, railway axle material RSA1 used for evaluation of fretting fatigue life. Plain and fretting fatigue tests were carried out using rotary bending fatigue tester with proving ring and bridge type contact pad. Through these test, the following results are obtained: 1) it is found that the fretting fatigue limit of standard specimen decreased about 37% compared to the plain fatigue limit. 2) The early crack of Shinkansen type specimens initiated in contact area and final fractured below samp=214 MPa. 3) The early crack of all TGV type specimens initiated in rounded area and fractured. 4) Tire tracks and rubbed scars were observed in the oblique crack region and fatigue crack growth region of fracture surface. 5) The wear debris is observed on the contact surface, and oblique cracks at an earlier stage are initiated in contact area. These results can be used as useful data in a structural integrity evaluation of railway axle.