• Korean Journal of Plant Resources
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• v.19 no.6
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• pp.700-705
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• 2006

Present studies were performed to determine the physiology of seed germination in Viola species native to Korea. Twelve species, 1 variety and 1 form were collected, classified and used as materials: V. collina, V. blandaefomis, V. rosii, V. chaerophylloides, V. phalacrocarpa, V. patrinii, V. mandshurica, V. mandshurica for. albescence, V. seoulensis, V. yedoensis, V. keiskei, V. variegata, V. variegata var. chinensis, and V. verecunda. V. tricolor 'Helen Mount' was also used to compare wild with cultivated species. In order to investigate the effect of temperature on seed germination, seeds stored at $4{\pm}2^{\circ}C$ for 10 months or 4 years were incubated at 10, 15, 20, $25^{\circ}C$ under 16h illumination with 4 replicates per treatment. Seeds which had not germinated at $10^{\circ}C$ were transferred to $30^{\circ}C$ to assess the effect of temperature change in germination. Germination percent and the days of first, 40% and 80% germination were assessed. Capability of seed germination varied with taxon; Species belonging to subsection Patellares had high ability of germination, compared to species in the other subsections, and series Chinensis was the best among subsection Patellares. Species capable of high germination germinated in all temperatures with reasonably high germination rate, but the other species responded sensitively to temperature with different germination patterns. Higher the temperature, shorter the incubation time required for first, 40% and 80% of germination. Therefore, high temperature was effective in almost all species, not only for inducing high rate of germination but also the uniformity of germination. Temperature change from $10^{\circ}C\;to\;30^{\circ}C$ had a positive effect on seed germination.

• 보존과학연구
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• s.17
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• pp.123-160
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• 1996

There have been many studies and experiments regarding exhibition lighting. Many experiments on photochemical damaging effect and visibility resulted in a practice limited to assigning light levels and adjusting annual exposure time. The three damaging factors to the artifacts are intrinsicsusceptibility to absorb radiant energy, spectral distribution of light source and intensity of illumination and time of exposure. Dividing all the artfacts into three categories to suggest a recommended illuminance level causes some problems. Blue wool, for example, used as the reference material for susceptibility, is not a standard material representing museum artifacts. In the most light sensitive category, ISO class I or anything below have been excluded. The exposure time of one soure can be three times more than another sourece. The spectral distribution of the light source and the relative spectral responsibility of the artifact are not considered in the practice. So in case of very light sensitive material, the recommended illuminance is only the referring value and it is indispensable to check the characteristic of susceptibility of each artifacts. Daylighting is prevailing method to solve the psychological need of the visitors. However, it sould transparent, and should not diffused, and the green-house effect must be considered. llluminance uniformity should based on the maximum illuminance to handle the limitation of exposure for the conservation of a large sensitive object such as a painting. Damage index is not absolute reference for selecting the lighting source because it is experimented from the paper of low grade then calculated. Visibility should be increased by reducing the visual noiseand by planning of appropriate luminance contrast. This paper reviews the problems with the previous studies and experiment sand the current exhibition lighting design practice. The plan for museum showcase lighting is to check the susceptibility and to raise the visibility simultaneously.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.27 no.8
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• pp.395-401
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• 2015

Recently, many research studies have been carried out on the efficiency of light-shelf daylighting systems, especially comparing performance improvements and the limitations of reflective surfaces and their lighting performance. In this study, a crystal face reflective surface is proposed. The objective of the study is to evaluate the lighting performance of a crystal face light-shelf through a performance study. The performance study was carried out in a full scale test-bed in order to calculate the light distribution and energy consumption utilizing the standard indoor illumination as an index. The conclusions of the performance study are as follows. 1) The optimal angle of incidence for daylighting for both the operable flat type light-shelf and the crystal face light-shelf are taken in the natural environment on the dates of the winter and summer solstices, as well as the autumn and spring equinoxes. 2) The application and installation of the crystal face light-shelf can produce a 29.9%~34.3% increase of light distribution within the indoor space. However, the increase of light distribution can also lead to a decrease in the uniformity ratio, a design challenge that should be considered when applying a crystal face light-shelf. 3) It is possible to achieve a 7.98%~13.3% greater reduction in energy consumption when applying a crystal face light-shelf than when applying a flat type light-shelf. The increase in the number of crystal faces should concur with the analysis of the energy reduction. A limitation of the study is that only one predetermined pattern was performance tested for a crystal face light-shelf. In order to carry out further research on crystal face light-shelves, additional performance studies are needed based on alternative patterns and designs.

• Korean Journal of Plant Resources
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• v.17 no.3
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• pp.219-226
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• 2004

Transplantings of onion (Allium cepa L.) seedlings are required for higher germinability and uniformity. This study was done to determine effects of various seed treatments (seed cleaning, priming, GA$_3$, prechilling, drying, and light quality during seed drying) on germination and seedling emergence. Nongwoodaego and Changnyungdaego were used as cultivars for checking seed germination, and two cultivars and Cheonjuguhyeonghwang were investigated with seedling production rate. Seed cleaning using water prior to the other treatments greatly increased germination rate. Priming with 200mM Ca(NO$_3$)$_2$ solution somewhat alleviated the germination rate while GA$_3$ did not. Prechilling had the highest rate among the treatments. Seed drying after prechilling enhanced the rate compared to non drying, and during drying the prechilled seeds red light illumination showed the greatest rate in comparison with dark, blue, and far-red ones. Seedling production rate was enhanced in sequential treatments of seed cleaning, prechilling for 3 to 5 days, and red light treatment during 6 hour seed drying.