• Title/Summary/Keyword: morphological features

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Correlation defects of macrostructure with morphology of BGO crystals grown by low thermal gradient Czochralski technique

  • Shlegel, V.N.;Shubin, Yu.V.;Ivannikova, N.V.
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.13 no.1
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    • pp.1-4
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    • 2003
  • In the present work we consider morphological structure of the faces of BGO crystals grown by Czochralski technique under the conditions of low temperature gradient (0.1~1 deg/cm) and interconnection between the morphological features of faces at the crystallization front and the formation of defects within the crystal volume. It is demonstrated that the {112} faces retain stability while the growing surface deviates from the crystallographic (112) plane up to 1 degree. At larger deviation, the region of the stable facet growth passes either to the region of macrosteps or to the region of normal growth. depending on conditions.

Notes on Two Marine Algal Halymeniacean Species from Korea (한국산 해조 보들지누아리과 2종의 주해)

  • KANG, Pil Joon;NAM, Ki Wan
    • Journal of Fisheries and Marine Sciences Education
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    • v.27 no.6
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    • pp.1593-1601
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    • 2015
  • Two marine algal halymeniacean species were collected from eastern coast of Korea during the survey of indigenous species of algae. One is distinct from other similar species by foliose thalli with irregular shape and several branches and linear proliferations without division. The other is characterized by indistinct midrib, foliose unbranched thalli and refractive ganglioid cells in medulla. These two species are identified as Grateloupia latissima and Cryptonemia yendoi based on the morphological features, respectively. Morphological and taxonomic notes on these species are included in the present study. This is the first record of G. latissima and C. yendoi from Korea.

A Study on the Morphological Characteristics of the River Mouth in the East Coast and Analysis of It's Causes (동해안 하구 형태의 특성과 그 요인 분석에 관한 연구)

  • 이원환;송재우
    • Water for future
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    • v.8 no.2
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    • pp.65-74
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    • 1975
  • The east coast seems to have remarkably different features from the west and south coast in the geographical, geomorphological, and oceanographical senses. In this paper the auther wishes to introduce some results of investigation morphological characteristics of the river mouth in the east coast an of analysis of it's causes. There are various closing form in river mouth by many causes, but the east coast hs the same closing form(the ratio of closing; roughly 0.18), as well known, by the sand spit, and has not hydrological but littoral drift background. The river of the east coast is proved mature age from hypsometric analysis. The wave and longshore current must be principal factor to be considered, in the analysis of the closing phenomenon owing to littoral drift. The research of the blown sand is considered valuable for the next study of this subject.

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Taxonomical Studies of Three Unrecorded Entoloma Species in Korea

  • Cho, Sung Eun;Jo, Jong Won;Kwag, Young-Nam;Han, Jae-Gu;Han, Sang-Kuk;Oh, Seung Hwan;Kim, Chang Sun
    • The Korean Journal of Mycology
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    • v.47 no.4
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    • pp.281-289
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    • 2019
  • Since 2013, more than 100 Entoloma (Entolomataceae, Agaricales) collections have been made during field investigations of mushroom flora in Korea. Among these collections, three Entoloma species were identified as new records from Korea. Morphological examinations were made based on the macro- and micro-morphological features of the isolates collected during field visits. To ensure the identity of the isolates at the species level, DNA sequences from four gene regions (rpb2, ITS, 28S, and mtSSU) were compared. To the best of our knowledge, these are the first records of E. aprile, E. chytrophilum, and E. hirtipes in Korea. Comprehensive descriptions, photographs, and phylogenetic examinations are presented here.

The Complete Larval Development of Enocheir japonicus De Haan (Crustacea, Brachytira, Grapsidae) Reared in the Laboratory (동남참게 Enocheir japonicus의 유생 발생)

  • 김창현;황상구
    • The Korean Journal of Zoology
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    • v.33 no.4
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    • pp.411-427
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    • 1990
  • The complete larval development of Enocheir japonicus De Haan reared in the laboratory is described and illustrated. E. japonicus passes through 5 zoeal stages before metamorphosis to the megalopal stage. The megalopa and crab I inStar are attained in 17 and 27 days after hatching, respectively. The culture was carried out under a photoperiod of 14 h light and 10 h dark and a constant temperature of $25^{\circ}C$. Morphological charaderistics of each larval stage of this species are compared with those of E. japonicus from Japan. Morphological features between zoea I of the Varuninae are briefly discussed.

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Comparative Morphology and Seasonality of Campylaephora borealis and C. crassa (Ceramiaceae, Rhodophyta)

  • Seo, Kyung-Suk;Boo, Sung-Min
    • ALGAE
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    • v.20 no.4
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    • pp.325-331
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    • 2005
  • Populations of Campylaephora borealis (Nakamura) Seo, Cho et Boo and C. crassa (Okamura) Nakamura show a year-around occurrence of all life-history stages. Such a concurrency of life-history stages produces problems in recognizing species in the field. Here, we invesitgated the morphological variation and life-history stages of both species using a statistical character analysis. Life-history stage was correlated with the seawater temperature in C. borealis, whereas it was dependant on biomass in C. crassa. Thalli had dichotomous branches with adaxial branchlets. The statistics showed that the seasonal change in morphology of C. borealis was significantly different from that of C. crassa in seven qualitative characters and five quantitative characters (p < 0.001), although six quantitative features including tetrasporangial size were similar in both species. The morphological difference between the two species may be due to the annual variation of branchlet number and the variance of branch subangle.

Further observations on the genetics and morphometrics of Coolia santacroce (Dinophyceae)

  • Karafas, Sarah J.;Tomas, Carmelo R.
    • ALGAE
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    • v.30 no.4
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    • pp.275-280
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    • 2015
  • Coolia santacroce is a newly described epibenthic dinoflagellate species collected from the U.S. Virgin Islands. The original description indicates this species is unique from others in the Coolia monotis complex due to the relative size of the apical pore complex, broad range of pore sizes, and ribosomal DNA. The original description was done based on the isolation and cultivation of one isolate of the organism. In this study, we report three more isolates of Coolia santacroce collected from the Bahamas. Morphological observations were made using scanning electron microscopy that do not correspond to those from the original description, indicating the variability of the morphological features. However, analysis of the D1 / D2 regions of the large subunit rDNA places the three strains in a strongly supported monophyletic clade with the type specimen.

Plocamium serrulatum(Plocamiaceae), a red algal species newly recorded in Korea

  • Kang, Pil Joon;An, Jae Woo;Nam, Ki Wan
    • Korean Journal of Environmental Biology
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    • v.38 no.3
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    • pp.476-480
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    • 2020
  • A marine red algal species was collected from Uljin, located on the eastern coast of Korea, during a survey of marine algal flora. This alga shares the generic features of Plocamium, and is characterized by linear, flat and thin thalli with narrow axes, branches developing in alternating pairs from margins of the axes, two to four times alternately pinnately branching, linear or occasionally adaxially curved lowermost branchlets and distinctly and compactly clustered stichidia. In a phylogenetic tree based on rbcL sequences, the Korean alga nests in the same clade as P. serrulatum. The genetic distance between both sequences within the clade was calculated as 0.0-0.2%. Based on the morphological and molecular data, this Korean species is identified as P. serrulatum described originally from Taiwan. This is the first record of P. serrulatum in Korean marine algal flora.

New record of Chondrus retortus (Gigartinales, Rhodophyta) in Korea

  • Kang, Pil Joon;An, Jae Woo;Nam, Ki Wan
    • Korean Journal of Environmental Biology
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    • v.38 no.3
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    • pp.481-485
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    • 2020
  • A marine red algal species was collected from Honghyeon-ri, Namhae located on the southern coast of Korea during a survey of marine algal flora. This alga shares the generic features of Chondrus, and is characterized by short and thin, canaliculated and crisped fronds as C. retortus. Tetrasporangia are developed from shallow medullary cells on both sides of branches. In a phylogenetic tree based on rbcL sequences, the Korean alga nests in the same clade as C. retortus originally described from Japan. The genetic distance between both sequences within the clade was calculated as 0.0-0.1%. Based on the morphological and molecular data, the alga is identified as Chondrus retortus. This is the first record of C. retortus in Korean marine algal flora.

Texture Classification Based on Morphological Subband Decomposition (모폴로지컬 부대역 분할에 기초한 질감영상 분류)

  • 김기석;도경훈;권갑현;하영호
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.31B no.12
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    • pp.51-58
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    • 1994
  • Mathematical morphology based on set theory is easy to be implemented in parallel and can be applied to various fields in image analysis. Particularly mophological pattern spectrum can detect critical scales in an image object and quantify various aspects of the shape-size content. In this paper, texture classification using pattern spectrum based on morphological subband decomposition is porposed. The low-low band extracts pattern spectrum features, and the high-low, low-high, and high-high bands extrack the structural information. This approach has the advantages of efficient information extraction, less time-consuming, high accuacy, less computation, and parallel implementation.

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