• Title/Summary/Keyword: 반상근

Search Result 7, Processing Time 0.019 seconds

Effects of Temperature and Irradiance on the Growth of Basal Crust of Economic Red Alga Gloiopeltis tenax (유용 홍조류 참풀가사리(Gloiopeltis tenax) 반상근의 생장에 미치는 온도와 광도의 영향)

  • Lee, Hyeon Jeong;Kim, Young Sik
    • Journal of Marine Life Science
    • /
    • v.5 no.2
    • /
    • pp.64-71
    • /
    • 2020
  • Gloiopeltis tenax is one of the most economically useful species in China and Japan that has been applied to glue and food since ancient times. The material used in the experiment was a large quantity of basal crusts obtained from the culture of tetraspores that were released from the mature tetrasporophytes collected at Gyeokpori, Byeonsan-myeon, Buan-gun, Jeollabuk-do in Korea. The basal crusts were cut into quadrisect under a dissecting microscope so as to monitor the process of regeneration and growth. The cut crusts were cultured under varying conditions, where the photoperiod was 16:8 h L:D; the temperature range was 10, 15, 20, and 25℃; the irradiance range was 30 and 85 µmol photons m-2s-1. The quadrisect basal crusts grew to an oval shape, then formed a vertical axis of cylindrical shape. The maximum growth of basal crusts was 9.61±3.59 mm2 under the condition of 15℃ temperature and 85 µmol photons m-2s-1 irradiance, after 12-weeks culture. The mean relative growth rate after 12-weeks culture showed the maximum rate of 5.15±0.80 %day-1 at 15℃ and the minimum growth rate was 3.15±0.94 %day-1 at 10℃, with a statistically significant difference (p < 0.05). In conclusion, it has shown the possibility that growth of basal crusts of G. tenax is one of the good farming method of potential alga.

Tissue Culture of Grateloupia acuminata (Rhodophyta) from the Eastern Coast of Koea (동해안 홍조 지누아리사촌(Grateloupia acuminata) 식물의 조직배양)

  • Kim Hyung-Geun;Park Joong-Goo
    • Journal of Aquaculture
    • /
    • v.19 no.3
    • /
    • pp.216-221
    • /
    • 2006
  • The Effect of different temperatures and photon irradiance on the growth of crust and the regeneration of tissue fragments of the commercially important red alga Grateloupia acuminat Okamura were examined in laboratory cultures. The tetraspore developed into basal crusts and produced upright thalli. Crust grew very fast at $25^{\circ}C$ and $80{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ after one week in indoor culture. However, they stopped growing after three weeks. Maximum growth was $275{\mu}m$ in diameter. They required four weeks to get upright thalli at $5^{\circ}C$, while only three weeks were required at $10^{\circ}C$. When different light intensities were compared at $15^{\circ}C$, cells of the crusts were well differentiated $80{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ and consistently divided so that upright thalli were produced. In aeration culture, the upright thalli grew up to 6.5 cm in length within 4 months. Thus, it is possible to produce mass cultures of Grateloupia in the field. In addition, female and male gametophytes developed from the tetraspores and they were fertilized to produce tetrasporohyte thalli. By this procedure, the normal life cycle of the red alga G. acuminata was completed.

Horizontal Displacement Analysis of Electric Pole from Full Scale Pull-Out Test in Softground (연약지반에 시공된 전주의 실물인장실험을 통한 수평변위분석)

  • Ahn, Tae-Bong
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
    • /
    • v.23 no.12
    • /
    • pp.115-126
    • /
    • 2009
  • Many electric poles in the softground have been collapsed due to external load such as typhoon wind load. In this study, the location, numbers and depths of acnchor blocks as well as depth of poles were varied to find horizontal displacement of poles through pull-out tests. The 10 types of tests were performed, and lateral displacements showed differences depending on location, numbers and depth of poles. The bending is generated in the upper part at the initial load, but it moved to central part as load increased. The maximum horizontal displacement decreased to 1/1.6 at -0.5[m] depth of anchor block and 1.3[m] additional laying depth of poles into ground. Two anchor blocks of poles are better than one acnchor block system, but one anchor block system is recommended because difference of displacement is not too large, and constructibilty is bad due to increase of excavation for anchor blocks.

전북 남원 일대의 야외지질 학습자료 개발

  • Jo, Gyu-Seong;Jeong, Deok-Ho;Park, Gyeong-Jin;Jang, Hyeon-Geun
    • 한국지구과학회:학술대회논문집
    • /
    • 2010.04a
    • /
    • pp.66-66
    • /
    • 2010
  • 야외지질학습은 교실에서 경험할 수 없는 물질과 현상을 관찰하고 직접 경험할 수 있는 기회를 제공받을 수 있어서 매우 중요하다(Orion 1989). 또한 체험활동으로서 교실에서 학습한 내용의 구체적인 예를 제공하여 교육과정을 촉진시키는데 중요한 요소로 인식되고 있다. 일반적으로 야외 활동은 교실 활동보다 학생들의 경험과 훨씬 더 밀접히 관련되어 있기 때문에 보다 의미가 있을 수 있다. 야외실습 중에서 얻은 경험은 학생들이 그가 관찰한 것에 대해 읽도록 동기화시키고, 교과서와 자연조건에서의 실제적 경험 사이의 차이를 연결해 주는 다리를 제공해 줄 수 있다(홍정수, 장남기, 1997). 야외학습을 위한 적절한 장소는 먼저 학습주제나 목표와 부합되는 곳이어야 하며, 지리적으로 가깝고 안전한 곳이어야 한다(김찬종, 2008). 그렇기 때문에 각 지역별로 학습주제와 부합된 지역을 선정하여 야외지질 학습자료를 개발하는 것은 무엇보다 중요하다. 따라서, 본 연구에서는 전북 남원 일대를 중심으로 한 야외지질 학습자료를 개발하는데 그 목적이 있다. 전북 남원지역은 한반도의 중요지괴에 해당하는 영남육괴 지리산지구에 해당하며 편마암 복합체를 기저로 이를 관입하는 수 차례의 화성활동과 지구조운동으로 복잡한 지질양상을 보인다. 또한 지리산 지역은 평안분지와 경상분지의 일부가 보존되어 있고 지질시대를 달리하는 각종 화성암류가 골고루 분포하여 각 지질시대별로 화성활동과 지구조 운동이 활발했음을 시사해준다. 본 연구에서는 남원 지역의 지질학적 특징을 관찰하기 용이한 지역을 대상으로 총 5곳을 선정하였다. 남원 시내에 소재한 춘향대교 아래 지역은 중생대 쥐라기에 관입한 저반상의 남원화강암과 페그마타이트가 다수 분포하는 곳이다. 이 지역에서는 무수히 많은 관입암체를 찾을 수 있는데 다수의 지진과 지각변동이 있었음을 알 수 있다. 두 번째 장소는 다양한 바위들을 관찰할 수 있는 구룡계곡 일대이다. 이 장소는 오랜기간 동안 물의 흐름에 의해 풍화와 침식을 받은 다양한 크기의 바위를 관찰하고 구별함으로써 풍화에 따른 원마도의 관계, 바위들의 배치 형태를 통해 고지형 및 고수류의 방향을 유추해 볼 수 있다. 남원에서 장수 방향에 위치한 만행산 주변에는 흑운모편마암에 우세한데, 이 지역에서는 흑운모편마암에 나타나는 변성구조로 볼 때 높은 열과 압력을 받은 광역변성작용을 받는 것으로 판단된다. 또한 관입암체 내에 다양한 맥들이 관입을 해와 이를 통해 관입암체들의 상대연령을 판단해보는 학습자료로 활용될 수 있다. 네 번째 장소는 남원시 인월면 인풍리 소재의 인월 피바위 지역이다. 이 지역에서는 압쇄상 화강암이 주로 관찰되는데 이는 기원암인 반상화강암이 동력변성작용을 받아 생성된 것이다. 다섯 번째 지역은 지리산 내의 뱀사골로 지리산 인근에 분포하는 대표적인 편마암인 반상변정질 편마암을 관찰할 수 있다. 변정이란 변성작용을 받는 동안 형성되는 것으로 변성작용을 받는 동안 생긴 것도 있으나 경우에 따라 생성당시 원래 모암속에 포함되어 있는 반정들도 있다.

  • PDF

A Study on Lateral Movement of Bridge Abutment on Soft Ground (연약지반상 교대의 측방이동에 관한 연구)

  • 홍원표;한중근
    • Geotechnical Engineering
    • /
    • v.10 no.4
    • /
    • pp.53-66
    • /
    • 1994
  • In case of using pile foundation to support bridge abutments on soft ground, the soft ground often causes serious troubles such as lateral movement of the bridge abutments. The foundation piles in soil undergoing lateral movement is one of the typical passive piles. However, Generally, on design of the piles for abutments, the piles have not been considered as a passive piles; sofar:. Because it is difficult to assess the effect of the lateral movement on the desigin and reasonable design method is not established yet. In this study, several abutments, of which lateral movement was taken place, was investigated. Based on the investigation a criterion was presented to assess the lateral movement of the soft soil under backfill for abutment. By use of the criterion, the lateral movement of abutment could be predicted. As the results of thin study, it was anon that the lateral movement of abutment could be occured when the safety factor of slope stability is lese than either 1.5(without the pile effect) or 1.8 (with the pile effect). Especially, excessive lateral movements were occurred when the safety factor of slope stability is less than either 1.0(without the pile effect) or 1.1 (with the pile effect).

  • PDF

Analytical Investigation on the Deflection Characteristics of Steel Piles in Bridge Abutment for Aspect Ratio and Ground Properties (형상비 및 지반특성에 따른 교대 강관파일의 변위특성에 대한 해석적 연구)

  • Jang, Gab-Chul;Chang, Kyong-Ho;Han, Jung-Geun;Lee, Yang-Koo;Kim, Jong-Ryeol
    • Journal of Korean Association for Spatial Structures
    • /
    • v.7 no.4
    • /
    • pp.73-78
    • /
    • 2007
  • The surrounding ground was much transformed by the lateral movement on the soft ground, and consequently the stake basis was damaged. In this case the installed stake is ratted the passive stake, and is actively being researched. When the unevenly distributed load was applied on the stake, and thus the lateral ground pressure was operated, and then the lateral movement was occurred, and consequently the structure is influenced. However, prediction and mechanism for the relationship of piles and abutment deformation is not sufficient. In this paper, coupled three-dimensional finite element analysis, which can be described solid, plate and frame elements at the same time, is developed by the authors. The lateral movement of bridge abutment for the aspect ratio of steel piles on soft clay is clarified by using developed numerical analysis.

  • PDF

Deterioration Assessment and Structural‐Reinforcement of Stone Lantern of the Four Guardian Kings in Beopjusa Temple, Boeun (보은 법주사 사천왕석등의 비파괴 훼손도 평가 및 구조보강)

  • Choie, Myoungju;Lee, Myeong Seong;Jun, Yu Gun;Lee, Mi Hye;Kim, Yuri;Ha, Jun Kyeong
    • Journal of Conservation Science
    • /
    • v.33 no.1
    • /
    • pp.25-33
    • /
    • 2017
  • The stone lantern of the four guardian kings in the Beopjusa temple at Boeun was mainly made of biotite granodiorite consisting of porphyritic-textured potassium feldspar and included in ilmenite series. A base stone made of alkali granite was buried, after founded its place during an earlier restoration process. Cracking and break out are noticeable on this object. In addition, discoloration, salt crusting, and epiphytes were observed. The lantern was vulnerable in terms of physical and structural stability caused by cracking in the front and back of the light chamber and in the non-horizontal direction. According to the conservational condition of the stone lantern, structural reinforcement was carried out based on calculations, including those on the position, size, and anchor length of the titanium stiffener. Chemical and biological pollutants were washed off without damage to the surface of the stone material. Oxygenated iron pieces were replaced with titanium. Ethyl silicate was applied to the surface of the lantern for consolidation and smooth drainage.