• 제목/요약/키워드: Yielding curve

검색결과 112건 처리시간 0.022초

Studies on the Fruiting Phase of Rape Under the Different Cultural Conditions

  • Kae, B.M.
    • 한국작물학회지
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    • 제12권
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    • pp.77-87
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    • 1972
  • The fruiting phase of rape under transplanting and direct-sowing conditions has been studied at Mokpo during the 2 years period from 1970 to 1971. Two varieties, Yudal and Miyuki were used in this study. The planting space and sowing time were also incorporated into this study. The results could be summarized as follows: 1. The plant tape of rape was nearly umbrella-shaped of all, but has changed to the laid elliptical-shaped, broadly ovate and spindle-shaped under different varieties and cultural conditions in the plant diagram(Fig. 2). 2. The length of the primary branches for each nodes had a tendency to the symmetric apical curve with the apex at the upper 10-12th node in the transplanting. but to the upper bias apical curve with the apex at the upper 5-7th node in the dense-sowing(Fig.3). 3. The ear of main stem was longer, more pods, heavier 1, 000 grains and more grain yield than ear of primary branches of all, Especially, as for that, the rate of yield constitution per plant in the direct-sowing was higher than in the transplanting(Fig. 4, 5, 6, 7, 8, 9). 4. The ear-length of the primary branches for each nodes had a tendency to the relatively slowly apical curve with the apex at the upper 3-4th node in the transplanting, but to the lower bias apical curve with the apex at the upper 2nd node in the dense-sowing. Especially, the possibility of growth at the lower ears was few in the early variety (Fig. 4). 5. The number of pod per ear on the primary branches for each nodes had a .tendency to the curve of ear-length with the apex at the upper 5-8thnode in the transplanting and at the upper 4-5th node in the dense-sowing (Fig. 5). Accordingly, a high positive correlation was found between the ear-length and number of pod per ear (Table 2) 6. In the transplanting, the high rate of effective ear was from the upper nods to the 12th node, but below the 16-17th nodes was ineffective. However, in the early dense-sowing the high rate of effective was to the 7th node. but below the 10th nodes was. ineffective. Especially, in the early variety has difficult to secure of poi-numbers for ineffective of the lower nodes(Fig. 6.). 7. The density of pod setting of the ear of main stem was the longest of all ears, and the lower nods were, the shorter it became. That had a tendency to the evidently apical growth. However. in the early variety, it was lengthened according to growth of ear-length(Fig.7). 8. The pod-length of the medium nodes was longer than the upper and lower, and the possitive correlation between pod-length and number of grain per poi was very high(Table 2.). 9. In the grain yield per node of primary branches, the most yielding node of transplanting was the upper 9th node, of dense-sowing 4-5th node(Fig 8.), and the possitive correlation between grain yield per node and ear-length or number of pod per ear was very high(Table 2). 10. The grain yield of ear of main stem was higher than that of primary branches in the percentage of dependence for grain yield per plant. The limint node of 50% of dependence to cumulative grain yield per plant was the upper 7-8th node in tranplanting, in the early dense-sowing 4-5th node, and in tke late dense-sowing-3th node(Fig. 9). 11. In the weight of 1, 000 grains the lower nodes were, the lighter it becames in dense-sowing. Therefore, this was also lighter than in the transplanting to the (Fig. 10.). 12. The oil content of grain at the medium nodes was low in the early variety, but at the ear of main stem and upper 1st node it was extremely high(Fig. 11.).

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기존 비선형약산법들의 신뢰성 개선을 위한 비선형직접스펙트럼법 (The Nonlinear Direct Spectrum Method Improving Application and Reliability of Existing Approximate Nonlinear Methods)

  • 김재웅;강병두;전대한
    • 한국지진공학회논문집
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    • 제10권4호
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    • pp.55-66
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    • 2006
  • 본 연구에서는 강성골격곡선으로부터 산정한 구조물의 초기 탄성진동주기 $T_1$와 응답스트럼으로부터 산정한 비선형 유사가속도 $A_{1y}/g$ 및 연성비 ${\mu}$를 사용하여, 반복적인 계산과정 없이 복합구조물의 내진성능을 평가하는 비선형직접스펙트럼법(NDSM)을 고려한다. 다양한 지진과 복합구조물에 대한 NDSM의 신뢰성과 실용성을 비선형시각이력해석(NRHA) 결과와 비교 검토하였다. 본 연구의 결론은 다음과 같다. (1) NDSM은 강성골격곡선으로부터 기본진동주기와 비선형 항복강도를 구하면, 비선형 응답스펙트럼으로부터 직접적으로 구조물의 비선형 최대응답을 산정할 수 있는 실용적인 방법으로 사료된다. (2) NDSM의 응답을 정산해와 비교한 결과, 대부분의 모델이 단순평균의 관점에서 전체 해석모델 중 3/4이 약 20% 이하의 오차를 나타내었고, 일반적으로 비선형시각이력해석의 응답보다 크게 산정되는 것으로 나타났다.

토끼 혈장 중 피록시캄의 HPLC 분석 및 패취제 투여 후 경피흡수 (HPLC Analysis of Piroxicam in the Rabbit Plasma and its Bioavailability after the Transdermal Administration of Patches)

  • 신대환;박승혁;이경복;이종길;정연복
    • Journal of Pharmaceutical Investigation
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    • 제39권3호
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    • pp.177-183
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    • 2009
  • A rapid and sensitive reversed-phase high performance liquid chromatography (HPLC) method was developed for the determination of piroxicam in the rabbit plasma. After a treatment of plasma sample by liquid-liquid extraction, the drug was analyzed on an HPLC system with ultraviolet detection at 330 nm. HPLC was carried out using reversed-phase isocratic elution with a C18 column, a mobile phase of a mixture of acetonitril, doubly deionized water and acetic acid 43.74:56.00:0.26 v/v%) at a flow rate of 1.1 mL/min. The chromatograms showed good resolution and sensitivity and no interference of plasma. The calibration curve for the drug in plasma sample was linear over the concentration range of 0.01-2.0 ${\mu}$g/mL. The intra- and inter-day assay accuracies of this method ranged from 86.82% to 108.33% of normal values and the precision did not exceed 13% of relative standard deviation. The plasma concentration of piroxicam decreased to below the quantifiable limit at 12 hr after the i.v. bolus administration to rabbits following dose of 0.375 mg/kg yielding a apparen t plasma half life of 1.38 hr. The transdermal route prolongs plasma levels of piroxicam. The bioavailability, calculated from the dose-adjusted ratio of the $AUC_{transdermal}$ to the $AUC_{i.v.}$, was 7.44%. The plasma concentration of piroxicam was detected by 48 hr after the transdermal administration of patch at a dose of 32 mg/kg. This method was suitable for cutaneous absorption studies of piroxicam in the rabbit after transdermal administration of different types of dosages of the drug.

Effects of face-sheet materials on the flexural behavior of aluminum foam sandwich

  • Xiao, Wei;Yan, Chang;Tian, Weibo;Tian, Weiping;Song, Xuding
    • Steel and Composite Structures
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    • 제29권3호
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    • pp.301-308
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    • 2018
  • Properties of AFS vary with the changes in the face-sheet materials. Hence, the performance of AFS can be optimized by selecting face-sheet materials. In this work, three types of face-sheet materials representing elastic-perfectly plastic, elastic-plastic strain hardening and purely elastic materials were employed to study their effects on the flexural behavior and failure mechanism of AFS systematically. Result showed face-sheet materials affected the failure mechanism and energy absorption ability of AFS significantly. When the foam cores were sandwiched by aluminum alloy 6061, the AFS failed by face-sheet yielding and crack without collapse of the foam core, there was no clear plastic platform in the Load-Displacement curve. When the foam cores were sandwiched by stainless steel 304 and carbon fiber fabric, there were no face-sheet crack and the sandwich structure failed by core shear and collapse, plastic platform appeared. Energy absorption abilities of steel and carbon fiber reinforced AFS were much higher than aluminum alloy reinforced one. Carbon fiber was suggested as the best choice for AFS for its light weight and high performance. The versus strength ratio of face sheet to core was suggested to be a significant value for AFS structure design which may determine the failure mechanism of a certain AFS structure.

철근 콘크리트 휨부재의 연성지수에 관한 해석적 연구 (Analytical Study on Ductility Index of Reinforced Concrete Flexural Members)

  • 이재훈
    • 대한토목학회논문집
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    • 제14권3호
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    • pp.391-402
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    • 1994
  • 철근 콘크리트구조는 극한하중에서 연성파괴가 일어나도록 하는 것이 가장 중요한 설계개념의 하나이며 단면이 충분한 소성변형능력을 가지고 있을 때에는 한계상태설계법 개념을 도입하여 소성구조해석이나 모멘트 재분배를 수행하여 경제적인 단면을 설계할 수 있다. 따라서 휨연성지수는 설계된 철근 콘크리트 구조물의 휨거동을 예측하는데 뿐만 아니라 모멘트 재분배의 가능성을 판단하는데에도 이용된다. 그러나 휨연성지수 공식은 인장철근이 항복하는 순간의 곡률에 대하여 선형의 콘크리트 압축응력으로 가정하기 때문에 근사값의 휨연성지수를 계산하게 된다. 본 연구에서는 콘크리트와 철근의 응력-변형도 곡선을 이용한 수치해석으로 이론적 정해에 가까운 휨연성지수를 구하고 각 변수에 따른 휨연성지수의 변화와 공식의 오차, 복철근보의 최대철근량은 고찰함으로써 철근콘크리트 구조설계의 참고자료를 제공하고자 하며 모멘트 재분배에 관한 연구에 이용될 수 있는 철근 콘크리트 휨부재의 모멘트-곡률 곡선 모델을 제시하고자 한다.

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Changes in Photosynthetic Characteristics during Grain Filling of a Functional Stay-Green Rice SNUSG1 and its $F_1$ Hybrids

  • Fu, Jin-Dong;Lee, Byun-Woo
    • Journal of Crop Science and Biotechnology
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    • 제11권1호
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    • pp.75-82
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    • 2008
  • Functional stay-green is a beneficial trait that may increase grain yield through the sustained photosynthetic competence during monocarpic senescence in cereal crops. The temporal changes of photosynthesis and related characteristics throughout the grain filling period of a stay-green japonica rice "SNU-SG1" was compared in growth chamber conditions with three high-yielding cultivars(HYVs) and their $F_1$ hybrids with SNU-SG1. SNU-SG1 exhibited a typical characteristic of functional stay-green in terms of chlorophyll degradation and photosynthetic competence during grain filling. According to the photosynthesis-light response curve measured at 10 and 35 d after heading for the flag leaf, SNU-SG1 exhibited higher initial light conversion efficiency and thus higher gross photosynthetic rate at light saturation compared to HYVs. Light saturation point was not different among genotypes, ranging from 1000 to 1500 ${\mu}mol$ photon $m^{-2}s^{-1}$. Net photosynthetic rate at light saturation($P_{max}$) of the upper four leaves in SNU-SG1 was much higher and sustained longer throughout grain-filling than HYVs and $F_1$ hybrids. The sustained high photosynthetic competence of SNU-SG1 during grain filling was ascribed to the longer maintenance of high mesophyll conductance that resulted from not only high chlorophyll content and its delayed degradation but also the slow degeneration of photosystem II(PS II) as judged by chlorophyll fluorescence($F_v/F_m$) of flag leaves. $F_1$ hybrids showed slow degeneration of photosystem II similar to the male parent SNU-SG1 while chlorophyll degradation pattern close to female parents, thus exhibiting a little higher $P_{max}$ than female parents. These results suggest that SNU-SG1 has a typical functional stay-green trait that can be utilized for increasing rice yield potential through the improved dry matter production during grain filling.

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탄소섬유시트로 보강된 철근콘크리트 보의 휨 거동 (Flexural Behaviors of Reinforced Concrete Beams Strengthened with Carbon Fiber Sheets)

  • 김성도
    • 한국전산구조공학회논문집
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    • 제23권2호
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    • pp.227-234
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    • 2010
  • 탄소섬유시트로 보강된 철근콘크리트 보의 휨 거동을 조사하기 위해 하나의 기준보와 8개의 보강보(4개의 NU-보강보, 4개의 U-보강보)에 대한 휨 실험을 수행하였다. NU-보강보는 단부에 U 밴드를 적용하지 않은 보를, U-보강보는 U 밴드를 가진 보를 의미한다. 보강보 실험에서의 실험변수들은 탄소섬유시트의 보강겹수, U 밴드의 적용유무등이 있다. U 밴드를 가진 보강 시스템은 섬유시트의 계면박리 파괴를 지연시키고, U 밴드가 없는 보강시스템보다 나은 연성거동을 나타내 보였다. NU 보강보와 U 보강보 모두에서 섬유시트 겹수의 증가에 따라 최대하중과 휨 강성은 증가하였다. 실험결과들을 이론적인 비선형 휨 해석결과와 비교하였으며, 하중-처짐 선도 및 항복이전단계와 항복이후단계에서의 항복하중, 최대하중, 휨 강성 등이 잘 일치함을 확인하였다.

건물의 내진보강을 위한 캔틸레버타입 강재댐퍼의 실험 (Experimental study on a Cantilever Type Metallic Damper for Seismic Retrofit of Building Structures)

  • 안태상;김영주;박진화;김형근;장동운;오상훈
    • 한국강구조학회 논문집
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    • 제24권2호
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    • pp.149-161
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    • 2012
  • 최근에 신축 건물이나 기존 건물의 내진보강을 위해서 수동제진장치의 일종인 에너지소산형 제진장치의 사용이 매우 증가하고 있다. 제진장치는 선진국을 중심으로 개발되어 왔고 제한적으로 사용해 오고 있었지만, 최근에는 다소 저렴한 장치개발을 통하여 강진지역의 개발도상국으로도 그 사용이 확대되고 있다. 본 연구는 기존 또는 신축 건물의 내진보강을 위한 캔틸레버타입 강재댐퍼를 개발하고 제안하였다. 댐퍼에 대한 반복가력 실험을 바탕으로 이력거동 및 에너지소산능력을 조사하였다. 실험결과는 제진장치가 안정된 이력특성을 나타내고 있으며 큰 에너지소산능력을 갖고 있음을 보여준다. 실험결과를 바탕으로 댐퍼에 대한 간단한 하중-변위 이력모델을 제안하였다.

3. 간척지에서 수도개체군과 재식밀도에 관하여 (Study on the Salt Tolerance of Rice and Other Crops in Reclaimed Soil Areas 3. Response of Rice to Plant Population and Spacing in the Slty Soil Area)

  • 임형빈
    • Journal of Plant Biology
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    • 제12권2호
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    • pp.28-42
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    • 1969
  • Field studies were conducted with the split plot design of 20 treatment with a combination of 4 levels of 3, 5, 7 and 9 plants per hill and 5 levels of 60, 80, 100, 120 and 140 hills per 3.3$m^2$ on non-, low- and high-salty areas. Rice variety, Kusabue was grown under jthe standard fertilization and cultivating. Investigation was made on the productive structure of plant population, leaf-area index, light intensity curve by stratum of crop population at the panicle differentiation stage. The competition density effect on the photosynthetic capacity was low as the salt concentration became higher. This seemed to suggest the possiblity of an increased yielding capacity by closer planting in the salty areas. The effect of an increased number of hills per unit area was greater than that of an increased unmber of plants per hill due to the total leaf area and space distribution of the actie assimilation parts of rice plants. The number of ppanicle per unit area in the salty areas were increased when the number of hill per 3.3$m^2$ increased over an increased number of plants per hill, and the panicle weight was reduced by close planting in the non-lalty area, while it was not reduced so much in the salty areas. The number of grains per panicle was significantly decreased by close planting in the salty areas as in the non-salty area, and ratio of matured grain was not decreased even by close planting in the salty areas, while it was significantly decreased by close planting in the non-salty area. An increase in the rice yield was possible by close planting and greatly related to leaf area index in the salty areas but not in the non-salty area. Increasing the number of hills per unit area showed greater effect on the increase of the rice yield than an increased number of plants per hill in the salty areas. Relationships between the growth characteristics and the rice population affected by plant spacing mode for maximum production were discussed.

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강도비를 적용한 Rice-저항곡선과 변형경화를 고려한 $J_{\delta}$-저항곡선과의 비교 (On Reliability and Comparison of $J_{Rice}$-Resistance considering Optimal Strength Ratio and $J_{\delta}$-Resistance Curves converted from CTOD using Appropriate Strength chosen according to Strain Hardening Level)

  • 장석기
    • Journal of Advanced Marine Engineering and Technology
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    • 제26권1호
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    • pp.59-67
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    • 2002
  • The comparison of $J_{Rice}$-resistance considering a few strength ratio in Rice J-integral formula and $J_{\delta}$-resistance curves converted from experimental CTOD using appropriate strength chosen according to strain hardening level, n=10.6 (A533B steel) and n=8.1 (BS4360 steel) is carried out. The optimal dimensionless strength ratio like the factor of revision, (see full text)reflecting strain hardening level in Rice\`s experimental formula is found out and the reliability of appropriate reference strength chosen according to strain hardening level in different materials is investigated through doing that CTOD is transformed from $J_{\delta}$-integral using relationship between J-integral and CTOD. The results are as follows; 1) The optimal factor of revision is when m equals to 3 in (see full text) for Rice's and the above optimal factor of revision multiplies by coefficient, η in Rice's experimental formula instead of n=2, 2) and the pertinent reference strength for high strain hardening material like BS4360 steel is ultimate strength, $\sigma_{u}$ and for material like A533B steel is ultimate-flow strength, $\sigma_{u-f}$. The incompatible of the behavior of both experimental J-resistance curves using Rice's formula and CTOD-resistance curves for A533B and BS4360 steel by Gordon, et al., could be corrected using the optimal factor of revision in Rice\`s and the pertinent reference strength in J=$m_{j}$${\times}$$\sigma_{i}$${\times}$CTOD.