• 제목/요약/키워드: Morphological Evolution

검색결과 395건 처리시간 0.045초

Study on the Morphological Parameters and Evolution of Caragana microphylla Lam. Nebkhas in Inner Mongolia, China

  • Na, Yan;Eerdun, Hasi;Park, Ki-Hyung;Xia, Xian-Dong;Chun, Kun-Woo
    • 한국산림과학회지
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    • 제98권2호
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    • pp.156-162
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    • 2009
  • Nebkhas are widely distributed in farming-pastoral zones, typical grassland and desert margins. In the southeast of the Inner Mongolia Plateau, it is mainly distributed at the leeward of cultivated land and alluvial fan, severe deterioration rangeland and around residential points. Through the field measurement and statistical analysis of Caragana microphylla Lam. Nebkhas morphological parameters (length, width and height of Nebkhas are included), the results show that there were close correlations between the Nebkhas morphological parameters. The ranges of height and width of Nebkhas changed dramatically and have reached up to 11.44 m and 7.97 m respectively, however, the change range of height was relatively smaller and just 1.09 m. The morphological parameters change of the same type Nebkhas in the same region was large ranging from 0.56 m in height, 3.56 m in width to 6.96 m in length, while the morphological characteristics of the same type Nebkhas in different regions were much similar. A correlation between length and width was significantly positive, but the correlations between height and length, and between height and width were much more complicated. It can be concluded that the Nebkhas in Zhengxiangbai Banner and Taipusi Banner were at the initially growing stage, while the Nebkhas in Huade County belonged to a transitional stage from the growing phase to the stabilizing phase. The changing regularity of distance between Nebkhas in along-wind direction was not consistent.

SECULAR EVOLUTION OF SPIRAL GALAXIES

  • ZHANG XIAOLEI
    • 천문학회지
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    • 제36권3호
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    • pp.223-239
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    • 2003
  • It is now a well established fact that galaxies undergo significant morphological transformation during their lifetimes, manifesting as an evolution along the Hubble sequence from the late to the early Hubble types. The physical processes commonly believed to be responsible for this observed evolution trend, i.e. the major and minor mergers, as well as gas accretion under a barred potential, though demonstrated applicability to selected types of galaxies, on the whole have failed to reproduce the most important statistical and internal properties of galaxies. The secular evolution mechanism reviewed in this paper has the potential to overcome most of the known difficulties of the existing theories to provide a natural and coherent explanation of the properties of present day as well as high-redshift galaxies.

STUDYING THE MORPHOLOGY AND STAR FORMATION OF GALAXIES AS A PROBE OF GALAXY EVOLUTION

  • CHEN, HSUAN-JU;HWANG, CHORNG-YUAN
    • 천문학논총
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    • 제30권2호
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    • pp.511-512
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    • 2015
  • Star formation activities dominate the evolution of galaxies. Elliptical galaxies are believed to be old galaxies in the Hubble sequence, and elliptical galaxies at different evolution epochs might have different star formation activities and/or morphologies. We investigate the connection between star formation rates and the morphology of elliptical galaxies. With the Sloan Digital Sky Survey (SDSS) and the Galaxy Zoo, we select a sample of elliptical galaxies by morphology and consider their infrared emission as an index of star formation rate to study the relation between the star formation rates and their morphological properties, such as ellipticities. In addition, we select some nearby spiral galaxies with very low MIR emission to probe the mechanisms of these red spiral galaxies. We display our preliminary results and discuss their implication on the evolution of galaxies in this poster.

Capturing the Underlying Structure of a 'Segment-line' City: Its Configurational Evolution and Functional Implications

  • Ling, Michelle Xiaohong
    • 국제초고층학회논문집
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    • 제6권2호
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    • pp.139-147
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    • 2017
  • Analyzing morphological evolution over a long period of time is deemed an effective way to identify problems occurring in the process of urban development, in addition to achieving a fundamental understanding of socio-cultural changes and growth rooted from the context. As far as the urban morphology is concerned, Hong Kong is characterized by its unique high-density and compact layout patterns, which have aroused the interest of a number of authors in the urban design domain. Whilst an increasing number of redevelopment projects in Hong Kong were criticized for ignoring and destroying the old urban fabric, there is a need for research to investigate the origins and changes of various urban patterns and their implications for society. By employing the theories and techniques of space syntax, this paper accordingly provides a morphological analysis based on the Wanchai District - a 'Segment-line' city, which particularly epitomizes various urban grids of Hong Kong and may have different implications for functional aspects. By axial-mapping the urban layouts of five stages of growth since 1842 and subsequently investigating their spatial and functional transformation over the past 170 years, this paper identifies a series of spatial characteristics underlying different grid patterns, as well as achieves a precise understanding of their ever changing relationship. Based on these understandings, this paper intends to provide valuable reference and guidance for upcoming spatial development in Hong Kong and other regions.

질소추비와 생장조정제 Inabenfide 처리가 벼 도복 및 에틸렌 발생에 미치는 영향 (Effect of Inabenfide and Nitrogen Top-Dressing on Ethylene Evolution and Lodging in Rice)

  • Lee, Sang-Chul;Takeshi, Tanabe
    • 한국작물학회지
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    • 제38권5호
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    • pp.383-390
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    • 1993
  • 본 실험은 1992년 일본 동경농업대학 온실에서 질소 추비와 생장억제제 처리가 벼의 생육과 도복형질에 미치는 형태학적 특성과의 관계를 조사함과 동시에 내성 에틸렌 발생에 미치는 영향을 구명하기 위하여 실험을 수행한바 아래와 같은 결과를 얻었다. 1. 식물생장억제제인 Inabenfide는 초장은 감소시켰지만 수량구성요소, 엽록소 함량, $CO_2 동화량 및 분벽에는 변화가 없었다. 2. Inabenfide를 수잉기에 처리하였을 때 절간 신장을 감소시켰으나, 세 번째와 네 번째의 절간 직경과 줄기의 두께를 증가시켰다. 3. 질소추비는 대체로 초장과 $CO_2 동화률에는 뚜렷하게 영향을 나타내지 않았다. 4. 에틸렌 발생은 생장억제제에 대하여 많은 변화를 보여 주었으며 Inabenfide를 출수 15일 전에 처리하였을 때 에틸렌 발생은 무처리구보다 낮게 나타났다. 5. 질소 추비량에 따른 에틸렌 발생은 추비량이 많을 때 발생량이 높았으며 질소 추비와 에틸렌발생 사이에는 높은 상관관계가 있는 것으로 나타났다.

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수소 생성 광합성 세균 Rhodobacter sphaeroides KS 56 분리 (Isolation of Hydrogen Evolution Photosynthetic Bacteria Rhodobacter sphaeroides KS 56)

  • 이은숙;권애란
    • 한국식품영양학회지
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    • 제10권4호
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    • pp.549-552
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    • 1997
  • 혐기성 광조건의 낮은 농도의 NH4+ 존재하에서 포도당으로부터 많은 양의 수소를 생성하는 홍색 비유황 광합성 세균을 수계혐기층으로부터 분리하였다. 이 세균은 형태적, 배양적, 생리적 특성에 따라 Rhodobacter sphaeroides KS 56으로 동정되었다.

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