• 제목/요약/키워드: growth environment characteristics

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인위적인 수분처리가 물푸레나무와 들메나무의 생장과 엽형특성에 미치는 영향 (Effects of artificial water treatment on the growth and leaf characteristics of Fraxinus rhynchophylla and Fraxinus mandshurica)

  • 정진철;최정호;박경우;유세걸;이수원;배종향
    • 생물환경조절학회지
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    • 제16권2호
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    • pp.135-141
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    • 2007
  • 인위적인 수분처리에 대한 묘고생장 결과 물푸레나무는 수분처리의 영향을 크게 받지는 않았으나, 토양수분이 감소할수록 생장이 감소하였고, 들메나무는 상대적으로 토양수분이 높은 처리구$(78{\sim}90%)$에서 높은 생장을 보였다. 물푸레나무와 들메나무의 근원직경 또한 토양수분이 감소할수록 생장이 감소하는 경향을 보였다. 물질생산량의 변화는 물푸레나무의 경우 잎, 줄기, 뿌리 등 건중량이 각 처리구별로 토양내 수분이 낮아질수록 통계적으로 유의성을 보이면서 감소하는 경향을 나타냈으며, 토양수분이 $78{\sim}90%(A)$인 처리구에서는 상대적으로 $18{\sim}30%(D)$ 처리구에 비해 약 2배 이상 높은 물질 생산량을 나타 냈다. 들메나무도 각 처리구간에 차이를 보이면서 A처리구와 D의 처리구에서는 통계적으로 유의성을 보였다. 이는 토양수분이 묘목의 수세 약화 및 잎을 포함한 조직의 연화 등 생리적인 부분에 영향을 미치는 것으로 생각된다. 물푸레나무와 들메나무의 엽 특성중 SLA는 토양수분처리에 따라 통계적으로 유의성을 보이진 않았지만 처리구간 수분함량이 적을수록 감소하는 경향을 나타냈다. 그러나 LAR과 LWR의 경우에는 각 처리구간 토양내 수분함량이 적을수록 통계적으로 유의성은 나타나지 않았지만 증가하는 경향을 나타냈다.

가속기 백색광 X-Ray Topography를 이용한 CVD 단결정 다이아몬드 내부 전위 분석 (Dislocation Analysis of CVD Single Crystal Diamond Using Synchrotron White Beam X-Ray Topography)

  • 유영재;정성민;배시영
    • 한국전기전자재료학회논문지
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    • 제32권3호
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    • pp.192-195
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    • 2019
  • Single-crystal diamond obtained by chemical vapor deposition (CVD) exhibits great potential for use in next-generation power devices. Low defect density is required for the use of such power devices in high-power operations; however, plastic deformation and lattice strain increase the dislocation density during diamond growth by CVD. Therefore, characterization of the dislocations in CVD diamond is essential to ensure the growth of high-quality diamond. In this work, we analyze the characteristics of the dislocations in CVD diamond through synchrotron white beam X-ray topography. In estimate, many threading edge dislocations and five mixed dislocations were identified over the whole surface.

암면큐브를 이용한 육묘에서 LED 광질에 따른 파프리카 묘의 생육 특성 (Growth Characteristics of Paprika Seedlings Affected by Different LED Light Qualities Raising Seedlings Using Rockwool Cube)

  • 이세형;고바울;배종향;구양규;김호철
    • 생물환경조절학회지
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    • 제31권1호
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    • pp.60-66
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    • 2022
  • 본 연구는 파프리카 육묘 시 다양한 LED 광질(red:blue = 10:0, 8:2, 2:8, white)에 따른 생육변화에 대하여 구명하여 수경재배용 묘 생산을 위한 전용육묘장의 기반기술로 활용하고자 수행하였다. 초장과 줄기직경의 생육은 red 비율이 높을수록 유의하게 길거나 굵었고, 엽면적은 LED red:blue = 8:2에서 가장 넓었다. 건물 중량도 엽면적과 동일한 경향이었다. LED white에서는 모든 묘의 소질에서 다른 처리들보다 뚜렷하게 저조하였다. 상대생장률은 red 비율이 높을수록 높은 경향을 나타내었고 순동화율은 blue 비율이 높을수록 높은 경향을 나타내었다. 따라서 본 시험에서 LED를 활용한 파프리카 육묘 시 초장, 엽면적, 단위엽면적당 건물생산능력 등을 고려하였을 때 혼합광을 이용하는 것이 적합하고 특히, LED red:blue = 8:2가 가장 적합한 것으로 생각된다. 그리고 red와 blue 파장의 적절한 혼합 비율을 통해 파프리카 묘의 초장 및 절간장을 제어할 수 있을 것으로 생각된다.

압력용기용 강의 저온 피로크랙전파 하한계 특성에 관한 연구 (A Study on the Fatigue Crack Propagation Threshold Characteristic in Steel of Pressure Vessel at Low Temperature)

  • 박경동;박상오
    • 한국해양공학회:학술대회논문집
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    • 한국해양공학회 2001년도 춘계학술대회 논문집
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    • pp.326-331
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    • 2001
  • In this study. CT specimens were prepared from ASME SA5l6 which was used for pressure vessel plates for room and low temperature service. And we got the following characteristics from fatigue crack growth test carried out in the environment of room and low temperature at $25^{\circ}C$, -3$0^{\circ}C$, -6$0^{\circ}C$, -8$0^{\circ}C$, -10$0^{\circ}C$ and -12$0^{\circ}C$ in the range of stress ratio of 0.1 by means of opening mode displacement. At the constant stress ratio, the threshold stress intensity factor range ΔKsub/th/ in the early stage of fatigue crack growth ( Region I) and stress intensity factor range ΔK in the stable of fatigue crack growth ( Region II) was increased in proportion to descend temperature. It assumed that the fatigue resistance characteristics and fracture strength at low temperature is considerable higher than that of room temperature in the early stage and stable of fatigue crack growth region. The straight line slope relation of logarithm da.dN -ΔK in RegionII, that is, the fatigue crack growth exponent m increased with descending temperature at the constant stress ratio. It assumed that the fatigue crack growth rate da/dN is rapid in proportion to descend temperature in Region II and the cryogenic-brittleness greatly affect a material with decreasing temperature.

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산느타리버섯 원목재배 시 수종별 생육 및 수량특성 (Growth and yield characteristics according to tree species in the log cultivation of Pleurotus pulmonarius)

  • 이재홍;이남길;문윤기;정태성;권순배;박영학;김인종
    • 한국버섯학회지
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    • 제14권3호
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    • pp.105-110
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    • 2016
  • 산느타리버섯의 원목재배 시험결과 플라스틱 콘테이너 상자($50cm{\times}35cm{\times}30cm$)내에 토양매립하였을 경우 '향산' 품종에서는 원목당 수량이 340 g 정도로 톱밥종균 접종과 액체종균 접종에서 큰 차이가 없었고, '호산' 품종에서는 톱밥종균 접종이 원목당 450 g으로 수량이 높았으나 액체종균 접종은 259 g으로 낮게 나타났다. 원목을 비가림하우스내 토양에 매립하였을 경우 미루나무에 비해 가중나무의 수량이 높게 나타났고, 품종에 있어서는 '향산' 품종보다 '호산' 품종의 수량이 더 높게 나타났다. 산느타리버섯의 적정 수종 선발시험에서는 버드나무와 벚나무가 '호산' 품종 및 '향산' 품종 모두에서 수량이 높게 나타났다.

꽃송이버섯의 균사 생장을 위한 배지 조건 최적화 (Optimization of Medium Composition for the Mycelial Growth of Sparassis crispa)

  • 김진우;천우재;채경희;김동관;손성호;김종국;임희재
    • 생명과학회지
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    • 제22권2호
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    • pp.200-208
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    • 2012
  • 본 연구에서는 균사의 액체 배양 특성 조사를 위하여 꽃송이버섯 균주 KGFS08과 KFRI746를 선발하였다. 균사 생장을 위한 우수 배지는 KTM 배지로 조사되었으며, 탄소원과 질소원은 각각 3% (w/v) starch와 0.3% (w/v) tryptone, 비타민은 folic acid로 나타났다. 따라서 액체 배양 최적 조건은 STK 배지[3% (w/v) starch, 0.3% (w/v) tryptone, 0.1% (w/v) $KH_2PO_4$, 0.1% (w/v) folic acid], pH는 4.0~5.0으로 확인되었다.

댐체 비탈면 녹화지역의 수목 생장 및 토양환경 특성에 관한 연구 (Studies on the Tree Growth and Soil Environmental Characteristics in the Planting Zone on the Back Slope of Dam)

  • 반권수
    • 한국환경복원기술학회지
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    • 제24권3호
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    • pp.85-98
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    • 2021
  • In this study, the characteristics of tree growth and soil environment were analyzed at 5 sites that had been planted on the back slope of dam for more than 15 years in Korea. First, as a result of investigating the growth of 15 trees planted on the back slope of the dam, the average height was 10.6m, diameter at roots was 27.3cm, and DBH was 22.9cm, showing good growth status of most of the trees. In particular, the growth levels of pine, hackberry, and oak were similar or better than those of general forests and artificial ground. As a result of excavating and investigating the roots of trees, horizontal roots grew well in the left and right directions of the back slope of the dam, and the growth of vertical roots was insufficient. Currently, the roots of trees do not directly affect dam safety, but they may continue to grow in the long term and interfere with dam management. Second, the physicochemical characteristics of the soil on the back slope of dam were generally above the intermediate level in terms of landscape design standards, and were similar to those of the domestic forest soil. Therefore, although it was judged to be suitable for plant growth, isolation of the site, soil acidification, and nutrient imbalance may affect tree growth and forest health in the long term. Through this study, it was possible to confirm the potential and applicability of planting area on the back slope of dam as an ecological base. Continuous monitoring is required for safety management and ecological value of dams in the future, and through this, it will be possible to secure the feasibility of planting trees on the slopes of new or existing dams and improving management.

현가장치재의 부식피로균열진전에 미치는 쇼트피닝의 영향 (An Effect of Shot Peening on Corrosion Fatigue Crack Growth of Suspension Material)

  • 박경동;안재필
    • 한국자동차공학회논문집
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    • 제14권3호
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    • pp.88-94
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    • 2006
  • The compressive residual stress, which is induced by shot peening process, has the effect of increasing the intrinsic fatigue strength of surface and therefore would be beneficial in reducing the probability of fatigue damage. However, the effect of shot peening in corrosion environment was not known. In this study, investigated is the effect of shot peening on corrosion fatigue crack growth of SAE 5155 steel immersed in 6% $FeCl_3$ solution and corrosion characteristics with considering fracture mechanics. The results of the experimental study corrosion fatigue characteristics of SAE 5155 are as follows; the fatigue crack growth rate of the shot peening material was lower than that of the non-peening material. And fatigue life shows more improvement in the shot peening material than in non-peening material. This is due to the compressive residual stress of surface increases resistance of corrosion fatigue crack propagation. It is assumed that the shot peening process improve corrosive resistance and mechanical property.

13~18세 청소년기 여학생의 체형 특성에 관한 연구 (A Study on the Somatotype Characteristics of Adolescent Girls between the Ages of 13 and 18)

  • 김상미;김소라
    • Human Ecology Research
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    • 제57권4호
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    • pp.513-522
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    • 2019
  • This study analyzes the characteristics of somatotype changes of girls from the ages of 13 to 18 that provide basic data on clothing construction for middle and high school girls. We use data obtained from body measurements of 1,590 adolescent girls 13 to 18 years of age provided in the 6th national anthropometric survey report. The differences among the age groups for 56 direct measurements were analyzed by ANOVA, and the structures of the differences by SNK (Students-Newman-Keuls test) were analyzed. The two major growth ages were 'ages 13-14' and 'ages 15-16'. The first major growth ages focused on all measurement items of height, length, circumference, breadth, depth and other items. The second one focused on measurement items of height and length of torso, circumference, and breadth of lower body. The major growth pattern of the age groups was 'ages 13<14&15<16&17&18' which appeared focused on the height and length items of upper body and torso, the width items of lower body and the circumference items of upper body and lower body. The measurement items of front length like waist front length, N.P. to B.P to waistline, N.P. to B.P., and B.P. to B.P. showed the growth pattern for 'ages 13<14<15<16<17&18'.

Dynamic Elasticities Between Financial Performance and Determinants of Mining and Extractive Companies in Jordan

  • Yusop, Nora Yusma;Alhyari, Jad Alkareem;Bekhet, Hussain Ali
    • The Journal of Asian Finance, Economics and Business
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    • 제8권7호
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    • pp.433-446
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    • 2021
  • This study aims to identify the elasticities and casualties of financial performance and determinants of the mining and extractive companies listed in Jordan's stock market over the 2005-2018 period. The conceptual framework is based on the Resource-Based View theory and Arbitrage Pricing theory is used to describe the relationship between the external environment and the financial performance of the companies. Profitability ratio (return on assets) is utilized as a proxy of financial performance measurement. Meantime, the company's characteristics, macroeconomic variables, and non-economic factors are utilized as independent factors. Data sources are panel data set for mining and extractive companies over the above period. Fully Modified Ordinary Least Square (FMOLS), Dynamic Ordinary Least Squares (DOLS), and Pooled Mean Group (PMG) methods are applied. The empirical findings indicated that company size, sales growth, financial leverage, liquidity, and GDP growth were the critical determinants of mining and extractive companies' financial performance in the Amman Stock Exchange. Thus, the findings conclude that company characteristics and GDP growth mainly drive financial performance. Moreover, the findings reveal that a bidirectional causal elasticity exists between GDP and financial leverage and return on assets (ROA). Sound financial performance can be obtained by paying more attention to GDP growth and firms' characteristics.