• Journal of Plant Biology
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• 제17권3호
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• pp.118-126
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• 1974

Mulberry plants cultivated in mid-Korea were studied on the growth habitat, canopy type, productive structure and vertical light intensity in relation to the quality of mulberry leaves for sericulture. The growth in length of new branch of summer cut mulberry in spring was vigorous on the uppermost of old shoot. Numbers of leaves on a branch were barely 4 leaves on lower than 20th branch from base, but those were 13 leaves on higher than 24th branch. Area of leaves completely expanded was broad on high branch, but narrow on low one. The form of canopy, the type of productive structure and the vertical light distribution depend upon varieties of cultivated mulberry plants were classified according to characteristic of each variety in two groups, respectively; globular and columnar form in canopy, broad leaves and narrow leaves types in productive structure, and seriously obstructured the light and fairly transmitted the light into lower leaf stratum invertical light distribution. Out of varieties of mulberry investigated, Suwon No. 4 and Rosang were belong to the former characters, but Illchiroe and Kaeryangsubun were to the latters. The values of leaf dry matter index and dry matter production produced by leaves were increased in direct proportion to the height of leaf stratum; the leaf dry matter index of the uppermost leaf was twice as much that of the lowest, and the dry matter production by the highest leaf was 17 times compared with that by the lowest leaf. It is assumed that the meagre leaves occurred in the lower leaf stratum of Suwon No. 4 and Rosang were caused to diminished the dry matter index and dry matter production in the under leaves of plant, which were affected by receiving the weak light.

• 한국수산과학회지
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• 제13권1호
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• pp.1-13
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• 1980

빛에 대한 어류의 행동을 조사하기 위하여, 쥐치 Stephanolepis cirrhifer, 붕장어 Astroconger myriaster, 붕어 Carassius cerassius에 빛의 세기가 서로 다른 여섯가지 인공광원으로 광자극을 주어, 그에 대한 반응을 주야에 각각 조사한 결과는 다음과 같다. 1. 제한된 실험수조내에서의 광자극에 대한 구간별분포는 세 어종이 모두 양단구간에 많이 모여 분포곡선은 대체로 U자형이 되었다. 2. 쥐치는 빛의 세기가 강할수록 광원으로부터 멀리 떨어진 곳에 많이 모이는 경향을 나타냈다. 집어율이 최대가 되는 평균수중조도는 0.7 lx(0.5-1.1 lx)로서 주야간에 같았다. 조명시간이 경과함에 따라 집어율이 증가하는 경향을 나타냈다. 3. 붕장어는 수중조도가 어떤 값보다 높아지면 광원에서 멀리 떨어지는 경향을 보였고, 집어율이 최대가 되 는 평균수중조도는 주간에 1.9 lx(1.2-2.9 1x), 야간에 5.2 1x(3.2-7.7 1x)로서 야간에 더 높았다. 집어율은 조명시간의 경과에 관계없이 거의 일정 하였다. 4. 붕어는 어느 실험광원하에서도 제 VI 구간에 많이 모였고, 강한 광원일수록 제 VI 구간에 더 많이 모이는 경향을 보였다. 야간에는 16.2 lx 정도에서 집어율이 약간은 높은 경향을 보였으나, 대체로 주야간 다같이 수중조도에 따른 집어율의 변화가 뚜렷하지 않았다. 조명시간 중 집어율이 일정한 증감추세를 보인지 않고, 불안정하게 변동했다.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2002년도 학술대회논문집
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• pp.71-75
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• 2002

The prismatic luminaire named as a dome pendent is considered to save energy and improve visibility. This luminaire is using prismatic rome, and is designed to be used in commercial and industrial high-bay applications where quality light levels and energy savings are imperative. Although this kind of luminaire needs an accurate optic calculation process, the lumanires are manufactured without such a process. Therefore the purpose of this study is to develop a numerical model to accurately predict luminous intensity distribution of luminaire with prism.

• 한국생활환경학회지
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• 제20권2호
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• pp.233-237
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• 2013

Daylighting affects the luminous environment and provides comfortable environment to the occupants. However, excessive daylighting might have negative influences on the visual comfort. Skylight, light intensity and distribution, and insolation could cause glare effects on the occupants. This study analyzed the effect of fenestration on the interior glare effects, and verified luminous environment adjustability through mock up test of conventional fenestration and 'Convergence Window System' by analyzation of luminance, luminance contrast, and glare effect. Consequently, room installed Convergence Window System was improved luminance contrast and PGSV Level.

• Animal cells and systems
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• 제7권3호
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• pp.197-205
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• 2003

White snakeroot (Ageratina altissima (L.) R. King & H. Robinson) as an invasive alien plant appeared more abundantly at lower elevations where frequent artificial interferences prevailed than at higher elevations where such impacts were less. They appeared abundantly in introduced forests such as black locust plantation but they did not appear or were rare in natural forests such as oak forest. But an exceptional phenomenon where white snakeroot did not appear was found in a Korean pine stand with dense cover afforested recently. Appearance status of white snakeroot in each section of trampling path depended on breadth of the path and relative light intensity. Growth of white snakeroot measured as the number of ramet per genet, height, and biomass was better near the trampling path and was reduced toward the forest interior. The growth was proportionate to the relative light intensity measured according to distance from the trampling path. Such results support the fact generally known in relation invasion and expansion of the invasive alien plants. From this viewpoint, we suggest a management plan that applies ecological restoration principles to address ecosystems infected with white snakeroot by restoring the integral feature of the degraded nature and more thoroughly conserving the remaining nature.

• Ocean and Polar Research
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• 제45권2호
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• pp.57-69
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• 2023

Growth responses along the gradient of water temperature, salinity, and light intensity and cytotoxicity against Artemia nauplii were explored using Ostreopsis sp. and Coolia canariensis strains, representing the two potentially toxic epiphytic dinoflagellate (EPD) species from Jeju coastal waters of Korea. Variation in maximum growth rate (GRmax) and maximum biomass yield (Ymax) along the environmental gradients was quite contrasting between the two strains, which appears to be reflected in the in situ abundance distribution of the corresponding genera. The more eurythermal characteristics of Ostreopsis sp. strain were in good agreement with the relative distribution of Ostreopsis spp. and Coolia spp. in 520 macroalgal samples collected from 6 stations. The more stenohaline C. canariensis strain was well matched by a markedly narrower range of salinities in the in situ distribution of Coolia spp. than the salinity range for Ostreopsis species. The differences in light adaptation between the high light-preferring Ostreopsis sp. strain and the more euryphotic C. canariensis strain were remarkably consistent with the distinct vertical profiles of Ostreopsis spp. and Coolia spp. abundance in the red alga Amphiroa sp. off Moom-seom. Cytotoxicity against Artemia nauplii in the Ostreopsis sp. preparation with 1000 cells ml^-1 was similar to that in C. canariensis preparation with 12000 cells ml^-1, which is noteworthy. Thus, the new potential cytotoxicity risks from C. canariensis along with the well-known toxic genus Ostreopsis may be introduced to Jeju coasts, which necessitates further exploration into the contrasting ecological niches occupied by EPD species in relation to their cytotoxicity.

• KIEAE Journal
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• 제13권2호
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• pp.47-52
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• 2013

The problems of light pollution first became an issue in the 1970s when astronomers identified the degradation of the night sky due to the increase in lighting associated with development and growth. As more impacts to the environment by lighting have been identified, many attempts have been made for reducing light pollutions. To prevent light pollution and increase energy efficiency, Seoul Metropolitan Government(SMG) replaced metal halide road lighting to LED luminaire in four arterial highway in Seoul. The present study compared the lighting characteristics of metal halide and LED luminaire in terms of Korea Standard for road lighting(KS A 3701) and BUG rating from Illuminating Engineering Society of North America(IESNA). The results showed that LED luminaire increased road surface luminance up to 2 times in average compared to the metal halide environment. Also, LED luminaire reduced the glare value by 2 times and luminous flux over 50% than the metal halide luminaire. In comparison with the BUG ratings, LED luminaire rated 1 degree lower for the backlight ratings and 3-4 degrees lower for the uplight ratings. The measured values testified that the LED luminaire is effective for roadway lighting and light pollution reduction.

• 한국광학회지
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• 제20권6호
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• pp.375-380
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• 2009

광학활성 동축 이중층 원통에 수직 입사하는 전자기 파동의 산란을 수치 계산 법을 써서 살펴 보았다. 앞의 논문에서 얻은 해석적인 해를 바탕으로 수치계산 프로그램을 개발했고, 산란광의 밝기와 편광 상태의 각도에 따른 분포를 몇 가지 예에 대해서 계산하였다. 이러한 수치계산 프로그램은 산란광의 밝기와 편광상태의 각분포를 재어 원통의 크기, 구조, 조성을 비파괴적으로 정확히 결정하는데 쓸 수 있다.

• 정보저장시스템학회논문집
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• 제9권1호
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• pp.10-16
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• 2013

Through the rapid development of LED TV, a large-area edge-lit backlight unit is widely researched in the display industry for enhancing the optical efficiency, luminous uniformity and slim design. In addition, an edge-lit backlight unit includes many optical sheets such as reflection sheet, prism sheet and diffuser sheet. However the function can be replaced by the carefully patterned light guide plate (LGP). Micro patterns which located on the top and bottom surface of light guide plate was designed by ray-tracing optical simulation. The designed patterns improved the light characteristics of LGP, including optical extraction efficiency and intensity distribution uniformity. These results suggest that it is very effective method to design edge-lit LGP with micro-patterns on both sides for large-area display and to reduce the fabrication cost.

• 원예과학기술지
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• 제17권4호
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• pp.494-496
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• 1999

새우난초의 자생지 생태환경은 낙엽활엽수림대로 비자생지보다 여름철 기온이 낮고 강수량이 많았으며, 상태습도가 연중 75~90%로 고른 분포를 보였다. 새우난초의 자생분포에 가장 중요한 영향을 끼치는 환경요인은 광(光)이었는데, 낙엽이 지기 전까지는 수관에 의해 강한 광선이 차단되었고, 자생지의 온도가 낮아졌으며, 광도가 400~1,500lux에서 가장 많은 분포를 보였다. 낙엽이 진 겨울철에는 30,000~50,000lux의 광이 유입되어 자생지의 온도를 높여 새우난초의 월동이 가능하였다. 새우난초는 낙엽활엽수림대에 자생하여 여름철에는 강한 광선의 차단효과를 얻었고, 겨울철에는 광선의 유입을 도모하고 낙엽으로 인한 피복으로 보온효과를 얻은 것으로 사료되었다.