• 아시안잔디학회지
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• 제6권2호
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• pp.73-81
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• 1992

잔디(Zoysia japonica)의 1차 생산성과 광조건과 상호작용을 평가하고 생리생태학적인 특성을 규명하기 위하여 차광을 조절한 상태에서 인공군락의 물질생산과 성장해석에 미치는 영향에 대하여 분석하였다. 그 결과의 요약은 다음과 같이 하였다. 1. RGR은 각 시험구 공히 이식후 20일경까지의 생장과정에서 높게 나타나고 이후 생장이 진행됨에 따라 낮아지는 경향을 보였다. 차광율이 높고 광조사 시간이 짧을수록 이식후 초기생장부터 현저히 낮은 치를 보였다. 2. NAR은 이식후 초기생장과정에서 높은치를 보였고 이후 생장이 진행됨에 따라 낮은 치를 나타내었으며 차광율이 높고 광조사 시간이 짧을수록 현저히 낮은 치를 보였다. 3. LAR은 Control구와 30% 차광구에서 이식후 초기생장과정에서 증가율이 높게 나타났으나 50% 및 70% 차광에서는 이식후 40일 이후부터 높게 나타나는 경향을 보였다. LAR은 RGR에 대하여 역의 상관관계를 나타내었다. 4. CGR은 각 공히 이식후 50일까지는 생장이 낮아지는 경향을 보였다. LAI와는 정의 상관을 나타내었고 최적엽면적 지수는 Control구와 30%, 50% 및 70% 차광구에서 각각 2.10, 1.75, 1.25, 0.90으로 나타났다.

• 한국환경농학회지
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• 제25권3호
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• pp.268-275
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• 2006

ALA (5-aminolevulinic acid) has been proposed as a tetrapyrrole-dependent photodynamic herbicide by the action of the protoporphyrinogen IX oxidase (Protox IX). A study was conducted to determine photodynamic herbicidal effect of ALA on seedling growth of rice (Oryza sativa L.) and barnyard grass (Echinochloa crus-galli Beauv. var. oryzicola Ohwi) under dry and wet conditions. ALA effect on early plant growth of rice and barnyardgrass was greatly concentration dependant, suggesting that it promotes plant growth at very low concentration and inhibits at high concentration. No significant difference in herbicidal activity of biologically and synthetically produced ALAs on plant lengths of test plants was observed ALA exhibited significant photodynamic activity regardless of PSDIP and its duration. Significant shoot growth inhibition by ALA soaking treatment exhibited apparently, indicating that ALA absorbed through root system was translocated into shoot part of plants. ALA reduced plant heights of rice and barnyardgrass seedlings by 6% and 27%, respectively, showing more tolerant to ALA in rice under wet condition. Leaf thickness was reduced markedly by ALA with increasing of ALA concentration, due to mainly membrane destruction and severe loss of turgidity in mesophyll cells, although the epidermal was little affected. It was observed that photodynamic herbicidal activity of ALA applied by pre-and post-emergence application exhibited differently on plant species, and that the activity of ALA against susceptible plants was highly correlated with growing condition.

• KSBB Journal
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• 제30권1호
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• pp.33-37
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• 2015

Recently, several health benefits of rice wine, makgeolli, were known due to the interest on the traditional Korean liquor and the researches on the rice wine are increasing. Organic acids produced during the process of rice wine fermentation play important roles in the taste and flavor. In this study, we have examined the optimal conditions for lactic acid production in rice koji as a carbon source. Skim milk was also used as a supplementary ingredient for the optimization of lactic acid fermentation. Bacterial growth of Lactobacillus sakei was monitored under this condition. The pH, acidity of the culture and the ethanol tolerance of this bacterium were also tested. Through these experiments, we were able to optimize the growth condition of lactic acid bacteria by the addition of skim milk. This was also able to affect the change of pH, acidity, sugar concentration and alcohol tolerance, which might contribute to the improvement of the quality of rice wine. The optimal condition for the growth was 2 days with 10% (w/v) of skim milk concentration. With these results, it was confirmed that rice koji was an effective carbon source for the growth of lactic acid bacteria.

• 한국결정성장학회지
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• 제24권4호
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• pp.151-157
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• 2014

The degradation mechanisms of thermal barrier coatings (TBCs) were investigated in different thermal fatigue condition in terms of microstructural analyses. The isothermal and cyclic oxidation tests were conducted to atmospheric plasma sprayed-TBCs on NIMONIC 263 substrates. The delamination occurred by the oxide layer formation at the interface, the Ni/Cr-based oxide was formed after Al-based oxide layer grew up to ${\sim}10{\mu}m$ in the isothermal condition. In the cyclic oxidation with dwell time, the failure occurred earlier (500 hr) than in the isothermal oxidation (900 hr) at same temperature. The thickness of Al-based oxide layer of the delaminated specimen in the cyclic condition was ${\sim}4{\mu}m$ and the interfacial cracks were observed. The acoustic emission method revealed that the cracks generated during the cooling step. It was considered that the specimens were prevented from the formation of the Al-based oxide by cooling treatment, and the degradation mode in the cyclic test was dominantly interfacial cracking by the difference of thermal expansion coefficients of the coating layers.

• 한국신뢰성학회지:신뢰성응용연구
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• 제14권2호
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• pp.129-136
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• 2014

Reliability test is focusing to detect the unexpected reliability failure and solve them for the high quality of products. The test data should be used to assess and project the current level of interesting product reliability and so it is very important to have the accurately assessing methodology with test data. There are two type of trend for test data as constant and changing one during testing and this paper shows the difference in the assessing results of these two cases. There is less information how to define the existence of reliability growth rate changing and calculate the parameters of the reliability growth models to make an accurate assessment with such condition, so i established the process and mathematical model to calculate the parameters at such condition to make reliability growth curve with high Goodness of Fit. I validated the new method with the data made from Monte Carlo Simulation and case from Demko (1993). Even the assessed result with the new methodology may be different with the case by case because of very diversity in test condition and testing product quality, but the process and method founded in this research can be applied to any case using Duane and AMSAA model for their test data assessment. I also present the evaluation method to see the effectiveness with new one which is a conventional knowledge and not popular to use, so it is possible to compare the results with the newly presented and conventional method for better business decision.

• 한국작물학회지
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• 제51권5호
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• pp.401-407
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• 2006

본 시험은 논과 밭재배에 따른 양파생육 및 채종용 모구 생산, 저장력의 차이를 구명하고자 실시하였으며 그 결과는 다음과 같다. 1. 시험전후 토양의 화학적 성분을 보면 질소, 인산, 칼리는 밭토양에서 많았으며 칼슘, 마그네슘, 나트륨은 논토양에서 많았다. 토양수분은 논토양에서 많았고 지중온도는 밭 토양에서 높았다. 2. 양파의 지상부 생육은 밭재배가 양호했으나, 구의 발달은 월동이후 초기에는 논재배에서 빨랐으나 구 비대기 이후에는 밭재배가 더 컸다. 3. 구의 평균 무게는 밭재배가 무거으며, 양파구의 수분함량은 밭재배가 더 많았다. 경도는 논재배가 더 단단했으며 당도는 밭재배에서 더 높았다. 4. 양파의 무기성분 함량은 질소, 인산, 칼리는 밭재배에서 많았고 칼슘, 마그네슘, 나트륨은 논재배에서 많았다. 5. 구중 분포를 보면 밭재배에서는 구가 큰 양파가 많이 분포했으며 논재배에서는 작은 크기의 양파가 많이 분포하였고 양파 채종에 알맞은 모구 생산 비율은 논재배가 $63{\sim}70%$로 밭재배에 비해 $8{\sim}26%$ 더 많았다. 6. 부패율은 논재배가 $27.2{\sim}34.6%$이고 밭재배가 $37.5{\sim}51.4%$로 논재배가 $8.7{\sim}24.2%$ 적었다.

• Environmental Engineering Research
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• 제23권2호
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• pp.216-222
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• 2018

The growth characteristics of Spirulina platensis were investigated using four photo-bioreactors with $CO_2$-mixed air flows. Each reactor was operated under a specific condition: 3% $CO_2$ at 50 mL/min, 3% $CO_2$ at 150 mL/min, 6% $CO_2$ at 50 mL/min, and 6% CO2 at 150 mL/min. The 3% $CO_2$ at 150 mL/min condition produced the highest algal growth rate, while the 6% $CO_2$ at 150 mL/min conditioned produced the lowest. The algal growth performance was suitably assessed by the linear growth curve rather than the exponential growth. The medium pH decreased from 9.5 to 8.7-8.8 (3% $CO_2$) and 8.4-8.5 (6% $CO_2$), of which trends were predicted only by the pH-carbonate equilibrium and the reaction kinetics between dissolved $CO_2$ and $HCO_3{^-}$. Based on the stoichiometry between the nutrient amounts and cell elements, it was predicted that depleted nitrogen (N) at the early stage of the cultivation would reduce the algal growth rates due to nutrient starvation. In this study, use of the photobioreactors capable of good light energy distribution, proper ranges of $CO_2$ in bubbles and medium pH facilitated production of high amounts of algal biomass despite N limitation.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집A
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• pp.501-506
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• 2001

The creep crack growth properties in 3.5NiCrMoV steel were investigated at $550^{\circ}C$ by using CT specimen under constant $C_t$ condition that was held during crack growth of 1mm distance. $C_t$ lely on load line displacement rate and $C^*$ usually increase with crack length though load is reduced in order to maintain constant $C_t$ value as crack growth. Fully coalesced area(FCA) ahead of crack tip tend to increase as $C_t$ increase to the critical value, and after that value FCA decrease. For the tertiary creep stage of crack growth test, the most of displacement is due to the steady state creep, except only small part due to the primary creep and other effects. Therefore, tests were mainly interrupted in the tertiary stage to obtain high value of $C_t$. At constant load and $C_t$ region, crack growth slope was 0.900 and 0.844 each, on the other hand $C^*$ slope was 0.480.

• Mycobiology
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• 제34권2호
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• pp.83-91
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• 2006

Characteristic growth patterns of Cordyceps militaris isolates on various media, under varying light conditions and at varying incubation periods were examined. Light was found to be the most critical single factor in determining the density, texture, and pigmentation of the mycelial culture of the fungus. However, under the light condition, the degree of pigmentation and mycelial density were found to be affected by the incubation period and type of medium. Irrespective of the variations in medium type or incubation period, there was no pigmentation of the mycelium under dark condition. Radial growth of the mycelium was faster under dark incubation rather than under light incubation. Abundant mycelial density and darkest pigmentation of C. militaris isolates were produced in nutritionally rich media like SDAY, SMAY and CZYA, suggesting that these media may fulfill all the requirements for vegetative growth of the fungus. Growth characteristics of C. militaris isolates could be easily observed by the simple agar culture method, which would be useful to characterize the phenotypic characteristics of large number of pure cultures of the fungus under given conditions of growth factors such as medium, light and temperature.

• 한국환경복원기술학회지
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• 제7권2호
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• pp.1-11
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• 2004

The purpose of this study was to determine usability as potted flowers and garden plants by controlled plant height using growth retardants. There was no significant difference on the dwarfing effect according to the degree of exposure the sun, but growth was well under full exposure to the sun. The plant height was decreased by application of Cycocel (CCC), Bonzi (paclobutrzol), Ancymidol, and Uniconazole compared to the control group, and treatment of Bonzi $5mg{\cdot}L^{-1}$ was most dwarfing effect for both full sun exposure or 70% controlled shading condition. No consistent different was found in stem diameter, leaf color change, the content of chlorophyll and anthocyanin when the concentration of plant growth retardants was altered. These factors were affected only by light intensity. In comparison to the results of the control group, leaf length, leaf width, plant width and petiole length were all reduced by the application of growth retardants.