• 한국환경과학회지
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• 제33권5호
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• pp.305-322
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• 2024

The aim of this study was to investigate the effects of artificial light sources on the germination and seedling vigor of lettuce, aiming to identify the optimal artificial light source for producing high-quality seedlings. Lettuce cultivar of 'Tomalin' and 'Seonpunggold' exhibited the highest seed emergence in the Metal halide(MH) lamp and High-pressure sodium(HPS) lamp treatment group, while the emergence rate parameter, T50, was the fastest in the HPS lamp treatment group. Both cultivars showed good growth characteristics such as number of leaves, root length, and stem diameter under RGB-LED, and their seedling vigor was excellent as well. The plant height was smallest in the Red + Green + Blue LED treatment, but the leaves were round and thick, resulting in higher biomass and dry weight. Single light sources of Red LED and Blue LED led to reduced growth compared with that under the mixed light treatments. Chlorophyll content in lettuce varied with the type of artificial light, with both cultivars exhibiting the highest chlorophyll content in the Red + Green + Blue LED treatment. The most suitable artificial light for lettuce seedling growth was the Red + Green + Blue LED treatment.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 B
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• pp.699-701
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• 2000

It leaves much room for improvement that UTM-01 is of practical use. Therefor we will design of UTM-02 system. The design of new magnet is based on light weight for bogie system. We used Maxwell-3D FEM for design of new magnet. The new magnet for UTM-02 that was reduced weight of magnet. 22kg, then it was increased ratio lift to weight is 9.87.

• 콘크리트학회논문집
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• 제27권2호
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• pp.169-176
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• 2015

현재까지 발표된 크기효과법칙은 보통중량 콘크리트에 기반하고 있어 파괴특성이 다른 경량골재 콘크리트에서는 그 활용성이 의문시되고 있다. 따라서 이 연구에서는 콘크리트의 기건단위질량이 압축강도의 크기효과에 미치는 영향을 예측할 수 있는 모델을 개발하고 기존 연구결과들을 모아 데이터베이스화하였다. 그리고 비선형 파괴역학에 근거한 Ba${\check{z}}$ant와 Kim and Eo의 예측모델 및 이 연구에서 제안한 식에 대한 실험상수들을 결정한 후, 상호 비교 분석하였다. 그 결과, 콘크리트의 기건단위질량을 고려한 본 연구의 예측모델이 Ba${\check{z}}$ant와 Kim and Eo의 예측모델보다 경량골재 콘크리트에 대한 실험결과를 더 잘 예측하고 있음을 알 수 있었다.

• 한국식품저장유통학회지
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• 제14권4호
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• pp.400-407
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• 2007

본 연구는 진열중 조도 처리에 따른 재래종 돈육과 개량종 돈육의 지방산화 및 육색 안정성을 비교하고자 실시하였다. 평균 출하체중 66 kg의 재래종 돼지(거세돈) 5두와 112 kg인 개량종 돼지($Landrace{\times}Yorkshire{\times}Duroc$, 거세돈) 5두를 도축하여 등심(M. longissimus) 부위를 $1^{\circ}C$에서 5일 동안 숙성한 다음 $4^{\circ}C$의 암실 및 3,000 lux에 7일 동안 진열하였다. 재래종이 개량종보다 높은 지방 함량을 가진 반면(p<0.05), 개량종보다 낮은 $C_{14:0},\;C_{18:3},\;C_{20:5}$ 함량을 가졌다(p<0.05). pH는 진열기간 동안 재래종이 개량종보다 낮았으며(p<0.05), 조도 처리시 두 돈육의 PH가 빨리 증가하였다. TBARS는 재래종이 진열기간 동안 개량종보다 빨리 촉진되었으며, 조도 처리시 더 빨리 증가하였다. 표면육색은 조도 처리시 두 돈육 모두 빨리 변질되었으나, 재래종의 육색이 개량종보다 붉고 진함을 더 오랫동안 유지하였다. 신선육의 기호도는 진열기간 동안 조도 처리에 의해 빨리 감소하였지만, 재래종이 개량종보다 높은 기호도를 보였다. 결론적으로, 진열기간 동안 재래종 돈육이 개량종 돈육보다 우수한 색택과 신선육 기호도를 보였으나, 개량종 돈육보다 낮은 지방산화 안정성을 보였다. 또한 식육을 조도 처리시 지방산화와 변색이 더 빨리 촉진되었다.

• Journal of Animal Science and Technology
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• 제64권5호
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• pp.985-996
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• 2022

This study investigated the effects of light intensity on growth performance, blood components, eye condition, and carcass characteristics of broiler chickens. Three hundred and fifty-two 1-day-old male chicks were assigned to one of four treatments (four repetitions per treatment, 22 birds per repetition) and reared in a floor pen for 5 weeks. From the second week, chicks were reared under four different levels of light intensity (5, 20, 35, and 50 lx) and the lighting duration was maintained at 18-hours light : 6-hours dark (18L : 6D). The feed intake and body weight were measured weekly. At 35 days of age, 12 birds per treatment were randomly selected for blood sampling, eye measurement, and carcass analysis. There were no significant differences in body weight gain, feed intake, and feed conversion ratio among treatments. Triglyceride levels in the serum were significantly higher in the 5 lx treatment, and creatinine was significantly lower in the 5 lx treatment (p < 0.05). The heterophil : lymphocyte ratios decreased significantly as light intensity increased (p < 0.05); however, other blood cell compositions were not affected by light intensity. Interleukin-6 content was significantly higher in the 5 lx treatment than in other treatments (p < 0.05), but the content of tumor necrosis factor-α was not significantly different among treatments. Serum corticosterone concentration was significantly higher at 5 lx than at 20, 35, and 50 lx (p < 0.05). The corneal diameter was the highest in 5 lx treatment (p < 0.05), and tended to increase as the light intensity decreased. Other eye parameters were not significantly different among treatments, but displayed a tendency to increase as the light intensity decreased. Carcass yield and part yields were not affected by light intensity. Meat quality parameters (pH, color, cooking loss, and water-holding capacity) did not show significant difference among the treatments. The results indicate that a light intensity of 5 lx may increase physiological stress or have a negative effect on broiler welfare, even if the performance and carcass characteristics are not affected. Therefore, a light intensity of 20 lx or above is recommended considering both the growth performance and welfare of broilers.

• 한국작물학회지
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• 제40권5호
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• pp.543-547
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• 1995

들깨잎의 주년생산을 위한 일장이 짧은 겨울동안 개화를 억제하기 위하여 들깨품종 엽실들깨, 옥동들깨에 대한 광조도별 0.5∼1 Lux, 3∼10 Lux, 30∼100 Lux, 야간조명시간별 10, 30, 60분간 처리로 실험을 수행한 결과를 요약하면 다음과 같다. 1. 엽실들깨는 옥동들깨보다 처리에 따라 정식후 개화소요일수는 1∼4일 정도 더 소요되었으며 광조도 0.5∼1Lux/야간조명시간 10분간 처리구 에서 개화소요일수가 가장 짧았으며 광조도 3∼10 Lux/야간조명시간 60분간 처리구와 광조도 30∼100Lux/야간조명시간 10, 30, 60분간 처리구 모두 개화가 되지 않았다. 2. 경장은 광조도 0.5∼1 Lux/야간조명시간 10분 처리구가 53∼56cm로 가장 작았고, 광조도 30∼100 Lux/야간조명시간 10분 처리구가 87∼91cm로 가장 컸다. 3.엽면적은 광조도 0.5∼1 Lux, 3∼10 Lux의 처리구에서는 야간조명시간이 길수록 광조도가 강할수록 엽면적은 증가되었으며 광조도 30∼100 Lux 처리구에서는 야간조명시간에 관계없이 엽면적은 큰 차이를 보이지 않았다. 4. 건물량은 광조도 30∼100 Lux/야간조명시간 10, 30, 60분간 처리구에서 주당 25∼29g으로 가장 무거웠고, 광조도 0.5∼1 Lux/야간조명시간 10분간 처리구에서 주당 16g으로 가장 낮았다. 5. 따라서 일장이 짧은 겨울동안의 개화억제 정도는 광조도 30∼100 Lux/ 야간조명시간 10분 정도 처리하면 효과가 커 그 이상 광조도와 야간조명시간은 엽생산을 위해 필요 없을 것으로 사료되었다.

• 생명과학회지
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• 제10권5호
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• pp.519-523
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• 2000

The action spectrum for light-induced growth of fruit body in Pleurotus ostreatus has been studied by irradiation at various wavelengths. Effective wavelengths were distributed from near ultraviolet to blue region of spectrum. The most effect of light was observed in the region between 340 to 520 nanometers. The growth weigth obtained from which has been irradiated 144 hours in the region of 340-520 nm increases 74%, on the contrary the observed growth weight has been observed in the longer wavelengths than 620 nm. The pileus size was promoted 30$\times$32% in the region of 340-500 nm, and retarded 22$\times$19% in the dark. the strip length was rearded 12% in the region of 340-500 nm, and promoted 38% in the dark. The color thickness for pileus is getting light in longer wavelengths.

• The Korean Journal of Ecology
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• 제20권4호
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• pp.285-291
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• 1997

The taxonomic characteristics of Eupatorium rugosum were reviewed and growth responses under different light intensities were investigated. Changes of soil and vegetation environments at experimental plots on Mt. Namsan were surveyed and the distribution pattern examined. The distribution of E. rugosum was closely related to the content of total nitrogen and available phosphorus in the soil. No competitors which could inhibit the growth of E. rugosum were present. Growth of E. rugosum was highest at a light intensity of 7, 500 lux, but dry weight was highest at a light intensity of 15, 000 lux followed by 30, 000 and 7, 500 lux. Growth in height of E. rugosum under a light intensity of 1, 500 lux continued even though the amount of growth was small. E. rugosum is found throughout the area of Mt. Namsan, and its density is higher at the roadside and in valley regions. E. rugosum appeared at 25 of 50 quadrats on Mt. Namsan, and the mean coverage of E. rugosum in survey quadrats was 12%.

• KSBB Journal
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• 제8권1호
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• pp.89-94
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• 1993

Thc effect of light and phylohormonc on the belalaln synthesis was tested using the suspension culture of a rod(bclalaln produulng) cell line from Phytolacca esculenta V. Houtte. Betalain synthesis of rod-cell 1ine was strongly dependent on the irradiation of blue light, but induced by hormone, IAA and/or kinetin, in dark conditions. In a light condition, however, 2 mg/l of IAA increased the betalain content about 30% (per gram fresh weight), whereas more than 0.5mg/l of kinetin remarkably decreased. The hairy root derived from the same plant was also observed for the blue light-dependent pigmentation in the root-tips. When the hairy root grown in dark was transferred to the light condition, the accumulation of betalain was initiated after 12hours. Such pigmentation was completely inhabited by addition of a protein synthesis inhibitor.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2009년도 추계학술대회
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• pp.333-336
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• 2009

장비의 리액터브 성분의 물리적 크기를 저감하고 동특성을 개선하기 위하여 동작스위칭 주파수를 증가 시키는 것이 우수하나 이러한 방식은 발열과 스트레스로 인한 전력소자의 파괴, 스위칭손실 증가로 인한 효율 감소등 다양한 문제가 발생하게 된다. 따라서, 본 논문에서는 이러한 문제점을 해결하기 위해 보조장치를 응용한 기동전류 회로를 적용한 하프브리지 방식의 Intense Pulse Light를 제안 하였다. 시뮬레이션 및 실험결과를 통해 20% 향상을 가져와 환자에게 보다 더 질적인 측정을 할 수가 있다고 확인하였다.