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A taxonomic study of Korean Artemisia L. using somatic chromosome numbers (한국산 쑥속의 체세포 염색체수에 의한 분류학적 연구)

  • Park, Myung Soon;Jang, Jin;Chung, Gyu Young
    • Korean Journal of Plant Taxonomy
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    • v.39 no.4
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    • pp.247-253
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    • 2009
  • Somatic chromosome numbers for 20 taxa of Korean Artemisia L. were investigated for the purpose of classification. Somatic chromosome numbers of treated taxa were 2n = 16, 18, 34, 36, 50, 52, 54, and therefore their basic chromosome numbers were x = 8, 9, 10, 13, 17. The chromosome number of A. japonica var. angustissima is being reported for the first time in this study. The chromosome numbers of 13 taxa were the same as in previous reports; A. capillaris (2n = 18), A. japonica var. hallaisanensis (2n = 36), A. japonica subsp. littoricola (2n = 36), A. annua (2n = 18), A. carvifolia (2n = 18), A. fukudo (2n = 16), A. keiskeana (2n = 18), A. stolonifera (2n = 36), A. sylvatica(2n = 16), A. selengensis (2n = 36), A. montana (2n = 52), A. lancea (2n = 16), A. sieversiana (2n = 18); however, the chromosome numbers of 6 taxa were different; A. japonica var. japonica (2n = 18, 36 vs 2n = 36), A. sacrorum (2n = 18, 54 vs 2n = 54), A. rubripes (2n = 16, 34 vs 2n = 16), A. indica (2n = 34, 36 vs 2n = 34), A. codonocephala (2n = 18, 50, 54 vs 2n = 50), A. argyi (2n = 34, 36, 50 vs 2n =34). The somatic chromosome numbers of Korean Artemisia are thought to be good characteristics for classifying some taxa such as A. japonica var. japonica, A. sacrorum, A. codonocephala, A. argyi, A. montana, A. sylvatica.

Effects of Amorphous Si3N4 Phase on the Mechanical Properties of Ti-Al-Si-N Nanocomposite Films Prepared by a Hybrid Deposition System (하이브리드 증착 시스템에 의해 합성된 나노복합체 Ti-Al-Si-N 박막 내 존재하는 Si3N4 비정질상이 기계적 특성에 미치는 영향)

  • An, Eun-Sol;Jang, Jae-Ho;Park, In-Uk;Jeong, U-Chang;Kim, Gwang-Ho;Park, Yong-Ho
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 2014.11a
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    • pp.304-304
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    • 2014
  • Quaternary Ti-Al-Si-N films were deposited on WC-Co substrates by a hybrid deposition system of arc ion plating (AIP) method for Ti-Al source and DC magnetron sputtering technique for Si incorporation. The synthesized Ti-Al-Si-N films were revealed to be composites of solid-solution (Ti,Al)N crystallites and amorphous $Si_3N_4$ by instrumental analyses. The Si addition in Ti-Al-N films affected the refinement and uniform distribution of crystallites by percolation phenomenon of amorphous silicon nitride, similarly to Si effect in TiN film. As the Si content increased up to about 9 at.%, the hardness of Ti-Al-N film steeply increased from 30 GPa to about 50 GPa. The highest microhardness value (~50 GPa) was obtained from the Ti-Al-Si-N film having the Si content of 9 at.%, the microstructure of which was characterized by a nanocomposite of $nc-(Ti,Al)N/a-Si_3N_4$.

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Microstructure and Mechanical Properties of Mo-Si-N Coatings Deposited by a Hybrid Coating System (하이브리드 코팅시스템에 의해 제조된 Mo-Si-N 박막의 미세구조 및 기계적 특성연구)

  • Heo, Su-Jeong;Yun, Ji-Hwan;Kang, Myung-Chang;Kim, Kwang-Ho
    • Journal of the Korean institute of surface engineering
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    • v.39 no.3
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    • pp.110-114
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    • 2006
  • In this work, comparative studies on microstructure and mechanical properties between $Mo_2N$ and Mo-Si-N coatings were conducted. Ternary Mo-Si-N coatings were deposited on AISI D2 steel substrates by a hybrid method, where AIP technique was combined with a magnetron sputtering technique. Instrumental analyses of XRD, HRTEM, and XPS revealed that the Mo-Si-N coatings must be a composite consisting of fine $Mo_2N$ crystallites and amorphous $Si_3N_4$. The hardness value of Mo-Si-N coatings significantly increased from 22 GPa of $Mo_2N$ coatings to about 37 GPa with Si content of 10 at.% due to the refinement of $Mo_2N$ crystallites and the composite microstructure characteristics. The average friction coefficient of the Mo-Si-N coatings gradually decreased from 0.65 to 0.4 with increasing Si content up to 15 at.%. The effects of Si content on microstructure and mechanical properties of Mo-N coatings were systematically investigated.

Asn124 of Cel5A from Hypocrea jecorina not only provides the N-glycosylation site but is also essential in maintaining enzymatic activity

  • Qin, Yuqi;Qu, Yinbo
    • BMB Reports
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    • v.47 no.5
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    • pp.256-261
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    • 2014
  • To investigate the function of N-glycosylation of Cel5A (endoglucanase II) from Hypocrea jecorina, two N-glycosylation site deletion Cel5A mutants (rN124D and rN124H) were expressed in Saccharomyces cerevisiae. The weights of these recombinant mutants were 54 kDa, which were lower than that of rCel5A. This result was expected to be attributed to deglycosylation. The enzyme activity of rN124H was greatly reduced to 60.6% compared with rCel5A, whereas rN124D showed slightly lower activity (10%) than that of rCel5A. rN124D and rN124H showed different thermal stabilities compared with the glycosylated rCel5A, especially at lower pH value. Thermal stabilities were reduced and improved for rN124D and rN124H, respectively. Circular dichroism spectroscopy showed that the modification of secondary structure by mutation may be the reason for the change in enzymatic activity and thermal stability.

Controlling of the heterogeniously growing GaN polycrystals using a quartz ring in the edge during the HVPE-GaN bulk growth

  • Park, Jae Hwa;Lee, Hee Ae;Park, Cheol Woo;Kang, Hyo Sang;Lee, Joo Hyung;In, Jun-Hyeong;Lee, Seong Kuk;Shim, Kwang Bo
    • Journal of Ceramic Processing Research
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    • v.19 no.5
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    • pp.439-443
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    • 2018
  • The outstanding characteristics of high quality GaN single crystal substrates make it possible to apply the manufacture of high brightness light emitting diodes and power devices. However, it is very difficult to obtain high quality GaN substrate because the process conditions are hard to control. In order to effectively control the formation of GaN polycrystals during the bulk GaN single crystal growth by the HVPE (hydride vapor phase epitaxy) method, a quartz ring was introduced in the edge of substrate. A variety of evaluating method such as high resolution X-ray diffraction, Raman spectroscopy and photoluminescence was used in order to measure the effectiveness of the quartz ring. A secondary ion mass spectroscopy was also used for evaluating the variations of impurity concentration in the resulting GaN single crystal. Through the detailed investigations, we could confirm that the introduction of a quartz ring during the GaN single crystal growth process using HVPE is a very effective strategy to obtain a high quality GaN single crystal.

Constant Time Algorithms for Region Expansion and Scaling of Linear Quadtrees on RMESH (RMESH 구조에서 선형 사진트리의 영역 확장과 스케일링을 위한 상수시간 알고리즘)

  • Woo, Jin-Woon
    • The KIPS Transactions:PartA
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    • v.11A no.3
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    • pp.173-180
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    • 2004
  • Quadtree, which 11 a hierarchical data structure, is a very important data structure to represent images. The linear quadtree representation as a way to store a quadtree is efficient to save space compared with other representations. Therefore, it has been widely studied to develop efficient algorithms to execute operations related to quadtrees. The region expansion is an operation to expand images by a given distance and the scaling If an operation to scale images by a given scale factor. In this paper, we present algorithms to perform the region expansion and scaling of images represented by quadtrees, using three-dimensional n${\times}$n${\times}$n processors on RMESH(Reconfigurable MESH). These algorithms have constant time complexities by using efficient basic operations to route the locational codes of quadtree on the hierarchical structure of n${\times}$n${\times}$n RMESH.

A Review of Domestic Research Trends Related to the International Classification of Functioning, Disability and Health (ICF): 2015-2020

  • Song, Ju-Min
    • Journal of the Korean Society of Physical Medicine
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    • v.16 no.3
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    • pp.65-80
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    • 2021
  • PURPOSE: This study was conducted as a literature review to analyze the research trends related to the International Classification of Functioning, Disability and Health (ICF) in Korea from 2015 to 2020. METHODS: Precedent studies were searched with the search term "ICF" or "international classification of functioning, disability and health" from the databases of RISS, KISS, DBpia, and Pubmed. The inclusion criteria are that the studies have been carried out in Korea from 2015 to 2020 using ICF by researchers consisting of one or more Koreans and have been peer-reviewed. RESULTS: Of the total 269 studies, 107 that met the inclusion criteria were analyzed. It was found that these studies were published at a similar frequency each year. The most common area of expertise was identified as the clinical area (n = 67), followed by special education (n = 21) and social welfare (n = 13). The study subject groups were mostly patients (n = 39), disabled people (n = 25), and related experts (n = 13). The most common research topic was functioning evaluation (n = 49) and followed by a literature review (n = 29), and the most frequently used components in all the areas of expertise were activity and participation (n = 98), body function and structure (n = 73), and environmental factors (n = 61). CONCLUSION: For the past six years, domestic ICF-related research has been conducted in a wider range of expertise areas on more subdivised subject groups. Continuous research, development of standardized curricula and contents, and development of coding tools are considered to be important in vitalizing the use of the ICF.

ON THE C-PROJECTIVE VECTOR FIELDS ON RANDERS SPACES

  • Rafie-Rad, Mehdi;Shirafkan, Azadeh
    • Journal of the Korean Mathematical Society
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    • v.57 no.4
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    • pp.1005-1018
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    • 2020
  • A characterization of the C-projective vector fields on a Randers space is presented in terms of 𝚵-curvature. It is proved that the 𝚵-curvature is invariant for C-projective vector fields. The dimension of the algebra of the C-projective vector fields on an n-dimensional Randers space is at most n(n + 2). The generalized Funk metrics on the n-dimensional Euclidean unit ball 𝔹n(1) are shown to be explicit examples of the Randers metrics with a C-projective algebra of maximum dimension n(n+2). Then, it is also proved that an n-dimensional Randers space has a C-projective algebra of maximum dimension n(n + 2) if and only if it is locally Minkowskian or (up to re-scaling) locally isometric to the generalized Funk metric. A new projective invariant is also introduced.

Deposition Behaviors of Ti-Si-N Thin Films by RF Plasma-Enhanced Chemical Vapor Deposition. (RF-PECVD법에 의한 Ti-Si-N 박막의 증착거동)

  • 이응안;이윤복;김광호
    • Journal of the Korean institute of surface engineering
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    • v.35 no.4
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    • pp.211-217
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    • 2002
  • Ti-Si-N films were deposited onto WC-Co substrate by a RF-PECVD technique. The deposition behaviors of Ti-Si-N films were investigated by varying the deposition temperature, RF power, and reaction gas ratio (Mx). Ti-Si-N films deposited at 500, 180W, and Mx 60% had a maximum hardness value of 38GPa. The microstructure of films with a maximum hardness was revealed to be a nanocomposite of TiN crystallites penetrated by amorphous silicon nitride phase by HRTEM analyses. The microstructure of maximum hardness with Si content (10 at.%) was revealed to be a nanocomposite of TiN crystallites penetrated by amorphous silicon nitride phase, but to have partly aligned structure of TiN and some inhomogeniety in distribution. and At above 10 at.% Si content, TiN crystallite became finer and more isotropic also thickness of amorphous silicon nitride phase increased at microstructure.

SUMMING AND DOMINATED OPERATORS ON A CARTESIAN PRODUCT OF c0 (𝓧) SPACES

  • Badea, Gabriela;Popa, Dumitru
    • Journal of the Korean Mathematical Society
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    • v.54 no.3
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    • pp.967-986
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    • 2017
  • We give the necessary condition for an operator defined on a cartesian product of $c_0(\mathcal{X})$ spaces to be summing or dominated and we show that for the multiplication operators this condition is also sufficient. By using these results, we show that ${\Pi}_s(c_0,{\ldots},c_0;c_0)$ contains a copy of $l_s(l^m_2{\mid}m{\in}\mathbb{N})$ for s > 2 or a copy of $1_s(l^m_1{\mid}{\in}\mathbb{N})$, for any $l{\leq}S$ < ${\infty}$. Also ${\Delta}_{s_1,{\ldots},s_n}(c_0,{\ldots},c_0;c_0)$ contains a copy of $l_{{\upsilon}_n(s_1,{\ldots},s_n)}$ if ${\upsilon}_n(s_1,{\ldots},s_n){\leq}2$ or a copy of $l_{{\upsilon}_n(s_1,{\ldots},s_n)}(l^m_2{\mid}m{\in}\mathbb{N})$ if 2 < ${\upsilon}_n(s_1,{\ldots},s_n)$, where ${\frac{1}{{\upsilon}_n(s_1,{\ldots},s_n})}={\frac{1}{s_1}}+{\cdots}+{\frac{1}{s_n}}$. We find also the necessary and sufficient conditions for bilinear operators induced by some method of summability to be 1-summing or 2-dominated.