• 한국작물학회지
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• 제32권4호
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• pp.386-391
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• 1987

재배광도와 재식밀도(40, 56, 90주/칸)가 인삼의 수량과 홍삼의 품질에 미치는 영향을 사양토산지삼포에서 수행하였다. 1. 20%의 광도는 수량이나 홍삼품질에서 5％ 관행광도에 이하여 유의차를 보이지 아니하였다. 2. 고광도는 줄기를 줄이고 엽면적을 적게 했으며 비엽중을 증대시켰으나 경직경이 적은 것으로 보아 조기낙엽의 피해 가능성이 있다. 3. 고광도는 엽록소함량을 적게 하였으나 Chl a /b값은 차이가 없었고 잎의 수분함량에 차이가 없었다(6 월 15일). 4 최대수량과 최대천지삼율을 나타내는 재식밀도는 칸당 64본으로 일치하였다. 5. 외관천지삼율은 천지삼율과 유의(P=0.01) 정 상관을 보였다. 6. 내백은 56 주구에서 유의성 있게 높았으며 백피는 90본에서만 유의성 있게 낮았다 7. 내공은 재식밀도와 유의성 있는 관계가 없어 밀식이 내공방지에 유효하다는 일반의 믿음과 일치하지 아니하였다.

• 한국수소및신에너지학회논문집
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• 제22권4호
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• pp.432-442
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• 2011

Anodized tubular $TiO_2$ electrodes (ATTEs) with three noticeably different lengths are prepared to determine their optimum length for the photo-driven activity in the reaction of Cr(VI) reduction and hydrogen evolution. The ATTEs with ethylene glycol have longer $TiO_2$ tubes (7-15.6 ${\mu}m$) than those with hydrfluoric acid (0.6-0.8 ${\mu}m$). These samples, which differ only in the length of the tubes, with a wall thickness of ca. 20 nm, consist mainly of an anatase crystalline phase after heat treatment at $650^{\circ}C$, since the anatase crystallites at the tube walls do not undergo transformation into rutile phase, due to the constraints imposed by the wall thickness. Among them, the medium size (ca. 8 ${\mu}m$) tubes provide the optimum conditions, irrespective of the light intensity, which is explained in terms of the correlation between the amount of photons and the adsorbed electron acceptors and their location. Photocatalytic Cr(VI) reduction leads to ca. 60% reduction of Cr(VI) even under 1 sun irradiation with the medium-sized anodized $TiO_2$ tubes, but only ca. 20% with the short- and long-sized tubes. For hydrogen evolution, tubes longer than 8 ${\mu}m$ do not exhibit better performance with any light intensity.

• 원예과학기술지
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• 제32권5호
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• pp.584-589
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• 2014

Jeffersonia dubia is a spring-flowering perennial found in rich forests in Korea and Northern China and has potential as an ornamental or medicinal plant. However, illegal picking and land use change have decreased the number of populations and overall population size of this plant in its natural habitat. Although J. dubia has been reported to be a shade-preferring plant, no study has determined the optimum light intensity for its growth. The objectives of this work were to observe the effects of various shading levels on the physiological responses of J. dubia and to determine the proper shading level for cultivation. Treatments consisted of four shading levels (0%, 50%, 75%, and 95% shade) imposed using black mesh cloth. The number of leaves and dry weight increased with decreased shading. The shoot-to-root ratio increased with increased shading, mainly due to decreased root dry weight under shading. Plants showed low net $CO_2$ assimilation rates and $F_v/F_m$ values combined with low dry matter levels when grown under 0% shade (full sunlight). These results indicate that J. dubia plants experience excessive irradiance without shading, resulting in damage to the photosynthetic apparatus. By contrast, the net photosynthesis rate increased as the shading level increased. $F_v/F_m$, the potential efficiency of PSII, was 0.8 under 95% shade, indicating that J. dubia is well-adapted under heavy shading. However, the low dry matter of plants in the 95% shade treatment indicated that the low light intensity under 95% shade led to a decline in plant growth. Thus, moderate light (50% shading) is recommended for cultivating J. dubia without physiological defects.

• ETRI Journal
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• 제39권6호
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• pp.859-865
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• 2017

This paper presents a method for determining the optimum active-area width (OAW) of solar cells in a module architecture. The current density-voltage curve of a reference cell with a narrow active-area width is used to reproduce the current density profile in the test cell whose active area width is to be optimized. We obtained self-consistent current density and electric potential profiles from iterative calculations of both properties, considering the distributed resistance of the contact layers. Further, we determined the OAW that yields the maximum efficiency by calculating efficiency as a function of the active-area width. The proposed method can be applied to the design of the active area of a dye-sensitized solar cell in Z-type series connection modules for indoor and building-integrated photovoltaic systems. Our calculations predicted that OAW increases as the sheet resistances of the contact layers and the intensity of light decrease.

• KSBB Journal
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• 제6권4호
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• pp.351-361
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• 1991

This study is on the investigation of hydrogen production and substrate removal by photosynthetic bacteria. After using of Rhodospillum rubrum KS-301 and IFO 3986, which are photosynthetic bacteria as strains, R. rubrum KS-301 was turned out a better strain. And result of experiment in which glucose and sodium lactate, components of wastewater, were used limiting substrates, showed that the productivity of hydrogen was indifferent with the kind of substrates. In batch experiments using free cells and immobilized whole cells, the decrease in hydrogen productivity was observed in the latter case. From the results of these experiments, specific growth rate of cells, specific utilization rate of glucose, and specific production rate of hydrogen were calculated. And each rate was expressed in the form of Monod equation of which parameters were estimated. Also the optimum condition of hydrogen production for free cells was $30^{\circ}C$, pH 7, and 12,000 Lux, and the optimum immobilized condition was as follows: initial immobilized cell concentration 1.0g/L, sodium alginate concentration 2% and light intensity 12,000 Lux.

• 한국작물학회지
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• 제42권1호
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• pp.22-32
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• 1997

국내 자생종인 광릉쥐오줌풀의 생육ㆍ수량 및 정유 함량에 미치는 온도 광도 및 토양 수분의 영향을 검토하여 쥐오줌풀의 재배법을 구명하고자 온도를 10, 15, 20, 25, 3$0^{\circ}C$ 등 5수준으로, 광도는 1,000, 2,500, 5,000, 20,000, 30,000, 40,000, 50,000, 60,000lux 등 8수준으로 처리하였고, 차광은 무차광 25% 차광ㆍ50% 차광구를 설치하였으며, 토양 수분 함량은 최대 용수량의 30, 45, 55, 70,.80, 90%등 6수준으로 각각 처리하여 시험한 결과를 요약하면 다음과 같다. 1. 온도와 쥐오줌풀 잎의 광합성간에는 고도로 유의한 2차 곡선회귀가 인정되었으며, 이 회귀식에 의해 산출한 쥐오줌풀의 최대 광합성을 위한 온도는 17.7$^{\circ}C$이었다. 2. 온도와 쥐오줌풀의 엽장ㆍ엽폭ㆍ엽병장 및 근 중간에는 각각 고도로 유의 한 2차 곡선회귀가 인정되었으며, 이 회귀식에 의해 산출한 뿌리 생장의 최적 온도는 약 20.3$^{\circ}C$였다. 3. 정유 및 extract함량은 온도 조건이 15~2$0^{\circ}C$에서 가장 높았다. 4. 광도와 쥐오준풀 잎의 광합성간에는 고도로 유의한 2차 곡선회귀가 인정되었으며, 이 회귀식에 의해 산출한 쥐오줌풀의 최대 광합성을 위한 광도는 40,000lux였다. 5. 쥐오줌풀의 정유 함량은 재배지역에 따른 차광의 유무와는 관계가 없었고, 정유 성분의 조성 비율은 재배지역 및 차광에 따라 영향을 받았다. 6. 토양수분 함량이 많을수록 엽병장ㆍ엽장ㆍ엽폭ㆍ근장이 길어지고, 뿌리 수량이 많아지는 경향을 보였는데, 토양 수분 함량이 최대 용수량의 80~90%일 때 쥐오줌풀의 생육이 양호하였고, 근중이 가장 많았다. 7. 쥐오줌풀 뿌리의 정유 및 extract함량은 토양 수분 함량이 90%에서 가장 많았고, 토양 수분함량이 낮을수록 감소하였다.

• 한국균학회지
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• 제36권1호
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• pp.31-35
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• 2008

잎새버섯의 생육환경 중에 광이 자실체 발생 및 생육에 미치는 영향을 구명하기 위하여 광질 3종류(청색광, 녹색광, 백색광), 광량 4수준(200, 500, 8000, 1200 lux)으로 시험한 결과는 다음과 같다. 광질이 자실체 발생 및 생육에 미치는 영향을 조사한 결과 백색광의 발이율이 청색, 적색보다 높고 초발이 소요일수도 3일로 청색광, 녹색광의 5일보다 빠른 것으로 나타났다. 생육일수는 백색광과 청색광이 14일로 녹색광(16일)보다 2일 빠르며, 전체 재배일수 또한 백색광이 52일로 청색광보다 1일, 녹색광보다 4일 단축되었다. 봉지당 수량성에서도 백색광이 242 g 으로 청색광(230 g)과 녹색광(216 g)보다 우수하였다. 백색광의 광량이 지질체 발생 및 생육에 미치는 영향을 조사한 결과 200 lux의 광량에서 발이율이 가장 우수하고, 초발이 소요일수도 4일로 500, 800, 1200 lux의 $7{\sim}8$일보다 $3{\sim}4$일 정도 빠른 것으로 나타났다. 생육일수는 500 lux가 9일로 가장 빨랐으며, 전체 재배일수는 200, 500 lux가 49일로 800, 1200 lux의 51일보다 2일정도 빨라 광량이 증가할수록 재배기간이 다소 길어졌다. 봉지당 수량성은 500 lux가 257 g 으로 가장 우수하였고, 광량이 증가할수록 갓의 크기가 신장되고, 갓 색이 다소 진한 것으로 나타났다.

• Asian-Australasian Journal of Animal Sciences
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• 제31권1호
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• pp.149-156
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• 2018

Objective: Broilers show clear preference towards red color light (RL). However setting of an optimum light intensity is difficult since dim intensities that favor growth reduce welfare. This experiment was conducted to test the most effective RL intensity regimen (Dim [5 lux; DI] vs high [320 lux; HI]) in combination applied at different growth stages that favors for both performance and welfare. Methods: Complete randomize design was adopted with 6 replicates. Treatments were; T1 = early DI (8-21 d)+latter HI (22-35 d); T2 = early DI (8-28 d)+latter HI (29-35 d), T3 = early HI (8-21 d)+latter DI (22-35 d), T4 = early HI (8-28 d)+latter DI (29-35 d) and T5 = control (white light; WT) (8-35 d) at medium intensity (20 lux). Body weight (BW), weight gain (WG), water/feed intake and ratio, feed conversion ratios (FCR) were assessed. Common behaviours (15) were recorded by scan sampling method. Lameness, foot pad dermatitis, breast blisters, hock burning damage were assessed as welfare parameters. Fear reactions were tested using Tonic Immobility Test. Ocular and carcass evaluations were done. Meat and tibiae were analyzed for fat and bone ash respectively. Results: On 35 d, the highest BW ($2,155.72{\pm}176g$), WG ($1,967.78{\pm}174g$) were recorded by T2 compared to WT ($BW_{WT}=1,878.22{\pm}155$, $WG_{WT}=1,691.83{\pm}160$). But, application of RL, either DI, or HI during early/latter stage had no significant effect on FCR. Under HI, birds showed much higher active behaviours. DI encourages eating. Though LI changed from DI to HI, same trend could be seen even under HI. The highest leg strength ($218.5{\pm}120s$) was recorded by T2. The lowest leg strength ($64.58{\pm}33s$) and the highest ocular weight ($2.48{\pm}1g$) were recorded by T1. Significantly (p<0.05) the highest skin weight ($162.17{\pm}6g$) but the lowest fat% in meat ($13.03%{\pm}5%$) was recorded by T2. Conclusion: Early exposure to DI-RL up to 28 days followed by exposure to HI-RL is the most favorable lighting regimen for optimizing production, better welfare of broilers and improving health benefits of meat.

• 한국환경보건학회지
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• 제26권4호
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• pp.29-37
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• 2000

Fenton’s oxidation process is one of the most commonly applied processes to the wastewater which cannot be treated by conventional biological treatment processes. However, it is necessary to minimize the cost of Fenton’s oxidation treatment by modifying the treatment processes or other means of chemical treatment. So, as a method for the chemical oxidation of biorefractory or nonbiodegradable organic pollutants, the Photo-Fenton-Reaction which utilizes iron(11)salt. $H_2O$$_2$ and UV-light simultaneously has been proprosed. Therfore, the purpose of this study is to test a removal efficiency of dye-wastewater and treatment cost with Fenton’s and Photo-Fenton’s oxidation process. The Fe(11)/$H_2O$$_2$ reagent is referred to as the fenton’s reagent. which produces hydroxy radicals by the interaction of Fe(11) with $H_2O$$_2$. In this exoeriment, the main results are as followed; 1. The Fenton oxidation was most efficient in the pH range of 3-5. The optimal condition for initial reaction pH was 3.5 for the high CO $D_{Cr}$ & TOC-removal efficiency. 2. The removal efficiency of TOC and CO $D_{Cr}$ increased up to the molar ration between ferrate and hydrogen peroxide 0.2:1, but above that ratio removal efficiency hardly increased. 3. The highest removal efficiency of TOC and CO $D_{Cr}$ were showed when the mole ration of ferrate to hydrogen peroxide was 0.2:3.4. 4. Without pretreatment process, photo-fenton oxidation which was not absorbed UV light was not different to fenton oxidation. 5. And Fenton oxidtion with pretreatment process was similar to Fenton oxidation in the absence of coagulation, the proper dosage of F $e^{2+}$: $H_2O$$_2$ was 0.2:1 for the optimal removal efficiency of TOC or CO $D_{Cr}$ .6. Also, TOC & CO $D_{Cr}$ removal efficiency in the photo-fenton oxidation with pretreatment was increased when UV light intensity enhanced.7. Optimum light intensity in the range from 0 to 1200 W/$m^2$ showed that UV-intensity with 1200W/$m^2$ was the optimum condition, when F $e_{2+}$:$H_2O$$_2$ ratio for the highest decomposition was 0.2:2.5.EX>$_2$ ratio for the highest decomposition was 0.2:2.5.

• 한국지반환경공학회 논문집
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• 제12권12호
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• pp.31-35
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• 2011

본 연구는 담수미세조류의 일종인 클로렐라를 발광다이오드를 이용하여 효율적으로 배양하기 위한 조건을 찾기 위해 수행되었다. 클로렐라 배양에 최적인 파장을 찾기 위해 청색, 적색, 백색, 그리고 혼합광을 클로렐라가 포함된 반응기에 각각 조사하여 성장속도 및 셀농도를 측정하였다. 적색파장이 클로렐라의 성장에 가장 효율적이었으며, 광량이 증가할수록 성장속도 및 셀농도도 광량에 비례하여 가장 많이 증가하였다. 본 연구를 통해 클로렐라를 효과적으로 배양하기 위해서는 적색파장의 발광다이오드를 광원으로 사용하는 것이 효과적임을 알 수 있었다.