• Korean Journal of Plant Resources
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• v.13 no.1
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• pp.11-17
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• 2000

In an effort to produce high quality Angelica gigas in the southern area of Korea, a variety of mulching materials were used to prevent withering during the summer. The experimental results are summarized as follows. Soil water content and temperature under various mulching materials were higher than those without mulching, in all the cases studied. Among various mulching materials P. E.(polyethylene) mulching material showed the highest effect. The appearance of weeds was the lowest when using the black P. E. mulching, while growth of weeds was the greatest when using transparent mulching. Growth and development of the plant were better with P. E. mulching than straw mulching or no mulching, allowed for more and bigger leaves. The bolting rate was about 2∼5%, with a slightly larger value under P. E. mulching. Under P. E. mulching, probably due to good physical properties of the soil the number of roots was large, and the length and diameter were good. Active growth of roots under P. E. mulching resulted in a yield increase of the plant. The black P. E. mulching material showed a prominent effect on suppression of weed growth, and the black P. E. material was considered to be the most recommendable among various P. E. mulching materials when there is a lack of labor.

• Korean Journal of Plant Resources
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• v.13 no.2
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• pp.124-130
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• 2000

In an effort to produce high quality Angelica gigas NAKAI in the southern area of Korea, a variety of mulching materials were used to prevent withering during the summer. The experimental results are summarized as follows. Soil water content and temperature under various mulching materials were higher than those without mulching, in all the cases studied. Among various mulching materials P. E.(polyethylene) mulching material showed the highest effect. The appearance of weeds was the lowest when using the black P. E. mulching, while growth of weeds was the greatest when using transparent mulching. Growth and development of the plant were better with P. E. mulching than straw mulching or no mulching, allowed for more and bigger leaves. The bolting rate was about 2∼5%, with a slightly larger value under P. E. mulching. Under P. E. mulching, probably due to good physical properties of the soil the number of roots was large, and the length and diameter were good. Active growth of roots under P. E. mulching resulted in a yield increase of the plant. The black P. E. mulching material showed a prominent effect on suppression of weed growth, and the black P. E. material was considered to be the most recommendable among various P. E. mulching materials when there is a lack of labor.

• Horticultural Science & Technology
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• v.34 no.1
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• pp.55-66
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• 2016

This study was carried out to investigate the effect of artificial light sources with different light qualities on the growth and flowering characteristics of a herbaceous long-day plant, Petunia ${\times}$ hybrida Hort. Seedlings of petunia cultivar 'Madness Rose' were potted, acclimated for one week, and grown in a phytotron equipped with tube- and bulb-type fluorescent lamps (FL tube and bulb), tube-type white light-emitting diodes (LED tube), halogen lamps (HL), metal halide lamps (MH), and high pressure sodium lamps (HPS) for 10 weeks. The temperature, photoperiod, and photosynthetic photon flux density (PPFD) in the phytotron were $22{\pm}2^{\circ}C$, 16 h, and $25{\pm}2{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$, respectively. Light sources combined with HL promoted stem elongation, and plant height and internode length decreased with increasing red to far-red (R:FR) ratio. FL tube + LED tube, HPS, and FL tube promoted branching, whereas plants grown under light sources combined with HL did not have any branches. Days to flowering (from longest to shortest) occurred as follows: FL tube + HL > FL tube + HL > MH > HPS = FL tube + FL bulb > FL tube + LED tube > LED tube > FL tube, indicating that reducing the R:FR ratio of the light sources promoted flowering. Only 20% of plants grown under an FL tube flowered, whereas under all other treatments, 100% of plants flowered. At 10 weeks after treatment, plants grown under HPS and MH had (cumulatively) 12 open flowers, and those grown under FL tube + FL bulb, LED tube, FL tube + LED tube, and HPS treatment had approximately seven flower buds. These results suggest that light sources with low R:FR ratios promote flowering and stem elongation in petunia, but they reduce its ornamental value due to overgrowth and poor branching.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.69 no.1
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• pp.15-24
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• 2024

Environmental factors play an important role in crop growth and development. In recent years, climate change has become a challenge that limits environmental factors. Light is an important environmental factor for photosynthesis in rice. In addition, temperature is one of the most important factors for rice production; thus, a 1℃ increase in temperature because of climate change can affect rice growth and development. Therefore, we investigated the effect of shading on the growth characteristics of rice under different temperature conditions from the vegetative stage to the flowering stage. Plants were grown at three different temperatures: 26℃/16℃ for 21℃, 29℃/19℃ for 24℃, and 22℃/32℃ for 27℃ in a phytotron. A 55% shade treatment was applied after 10 days of transplanting until the flowering stage. Plant height was not affected by the shading treatment. In the maximum tiller number response to shading, a lower tiller number and growth speed of tiller was found in the 27℃ condition. Among leaf characteristics, shading increased the flag leaf area, length, width, and effective leaf area; however, it decreased the leaf number on the main stem, especially at 27℃. In terms of stem characteristics, shading affected culm wall thickness in both varieties. Finally, regarding the panicle characteristics, lower panicle numbers, spikelet numbers per panicle, primary numbers, and secondary numbers per panicle were found under the shading treatment. Most of the desirable characteristics were affected by the shading treatment at 27℃. Overall, these results indicated that shading had a greater effect on rice plant growth at high temperature.

• Korean Journal of Medicinal Crop Science
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• v.25 no.4
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• pp.238-243
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• 2017

Background: The production method of ginseng seedlings for ginseng cultivation is very important to ensure healthy rooting system as well as high quality, and yield of the resultant plants. This study was carried out to compare the growth characteristics of 2-year-old ginseng plants that were produced from seedlings grown in self soil nursery (SSN), nursery soil (NS) or hydroponic culture (HC). Methods and Results: The shading prop used was composed of four-layered 4 polyethylene (blue 3 + black 1) shade screen. The management of main field was done by inserting oil cake (1,200 kg/10 a) and then allowing Sudan grass to grow for a year. Seedling transplantation was carried out on April 6. Root growth was measured on October 25. Root weight was observed to be excellent at 6.0 g, following SSN transplantation. Root length was 21.2 cm for HC seedlings, but these plants had a physiological disorder (i.e., rusty root), in 83.5% plants of this treatment. The ratio of PD/PT (protopanaxadiol saponins / protopanaxatriol saponins) was higher in NS seedlings. Plant analysis revealed that Fe content was lower in HC seedlings with high rustiness. The growth of 2-years-old ginseng was different following these varying seedling cultivation methods, but seedlings from NS were not different from those grown in SSN. Conclusions: For the propagation of 2-year-old ginseng plants, NS seedlings may be a good substitute for SSN seedlings.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.36 no.2
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• pp.127-133
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• 1991

Experiments were conducted to investigate the effect of light shading around the heading stage on grain yield and its components of rice. Early, medium, and late-maturing varieties were trected with the light shading of 50% and 75% from the reduction division stage to 20 days after heading date. Heading date were delayed 2-3 days, whereas the mid -late varieties, Sangpung- byeo, and Bongkwang- byeo were no significantly affected. Culm length was increased and panicle exsersion was reduced as the shading treatments become higher, and the degree of the shading effect was more intensive at 75% of shading. The rate of spikllet degeneration was higher at the secondary rachis branches than the primary rachis branch. The early maturing varieties showed the higher rate of spikelet degeneration. Spikelet number was reduced 12-15, spikelet sterility was increased and ripening rate was declined by the shading treatments. Grain yield was decreased by 30-40% at the shading treatment of 50%, and 50% at the shade treatment of 75%.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2022.10a
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• pp.2-5
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• 2022

Human organs in the body have a complex structure, and in particular, the small intestine is about 7m long, so endoscopy is not easy and the risk of endoscopy is high. Currently, the test is performed with a capsule endoscope, and the test time is very long. The doctor connects the removed storage device to the computer to store the patient's capsule endoscope image and reads it using a program, but the capsule endoscope test results in a long image length, which takes a lot of time to read. In addition, in the case of the small intestine, there are many curves due to villi, so the occlusion area or light and shade of the image are clearly visible during the examination, and there may be cases where lesions and abnormal signs are missed during the examination. In this paper, we provide a method of assisting small intestine capsule endoscopic lesion examination using artificial neural networks to shorten the doctor's image reading time and improve diagnostic reliability.

• Journal of Environmental Science International
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• v.16 no.11
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• pp.1313-1318
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• 2007

Illicium anisatum was bred under four different light intensity. Those condition were full sunlight(PPFD $1600{\mu} mol\;m^{-2}s^{-1}$), 30% treatment(PPFD $400{\mu} mol\;m^{-2}s^{-1}$), 50% treatment(PPFD $250{\mu} mol\;m^{-2}s^{-1}$) and 70% treatment(PPFD $100{\mu} mol\;m^{-2}s^{-1}$), respectively. Chlorophyll a and b were increased according to decrease of light intensity. Thirty percent and 50% treatment had not significant different in chlorophyll a and b. Thirty percent treatment was shown the best photosynthetic activity through invested photosynthetic rate, intercellular $CO_2$ concentration and water use efficiency. Photosynthetic activity trend of 50% treatment was similar to 30% treatment. Seventy percent treatment was shown the best photosynthetic activity at low light intensity but that was decreased to lower value than 30% and 50% treatment under high intensity. Control, bred full sunlight, was shown the worst photosynthetic activity at measured all light intensity. That result could imply that was caused by photo-inhibition because of long term exposed of shade tolerant plant at high light intensity. Leaf characteristics had not significant different in leaf length, width and area but leaf dry weight had similar trend to photosynthetic activity.

• Journal of the Korean Society of Costume
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• v.14
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• pp.145-165
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• 1990

This study examine closely conditions of costume between the Modernized period and Liberation with newspaper materials. Because newspaper generally appear society conditions in those days on rapid and across-the boad basis. The Modernized period is extremely change among history of costum (ordinance prohibiting top knots, allowance of foreign clothes putting on). Because this change have been spontaneously not by internal desired but Western input by the strong nation of imperialism to enclose Chosun, they was accepted by the general public later under the rule of Japaneses Imperialism. Consequently, study of costume play an important part periods between the Japanese annexation of Korea and Liberation. This study apply to newspaper characteric for costume, and closely examine an important costum condition of those days next time, and present costume material in those days that composed the account catalog appeared periods between the first publication(1920) of the Dong A II Bo, and in the year 1945, it is as follows. 1. Foreign clothes of men generally accept the general public on look at from form change, in the 1920's had come short Jackets and narrow throusers into fashion, in the 1930's had come trousers of generous waist band with broads shoulder and long Jackets. Catalog of Major clothes is as follows; Spring coat, Jacket, Vest, Shirt, etc. While pants had come trousers into fashion 2. Functional characteric of Foreign clothes was the possible acceptance of women's foreign clothes. It relate with much discussion to improve Korean development in those days and substitute foreign clothes for Korean clothes because of institence in those days to improve functional clothes life. 3. An improvement women's Korean clothes generally take aim at women's nipple liberation, substitute vest waist for skirt waist, appear seamless one-piece skirt of shade length, and long dress length of Jacket. 4. Children's clothes give an account of functional and sanitary conditions, handling method, washing method. 5. Clothes materials give account of foreign clothes material, artificial silk, furs, cotton fabrics, and etc. 6. Clothes management give an account of washing, keeping method, washing method of foreign clothes, and keeping of furs. 7. The hair generaly had come short hair into fashion in men's case, while accounts on long hair fashion of foreign nation effect in case of women. 8. Describing on beauty care manage primary beauty care, reform, plastic operation, and shade beauty care. Ideal beauty care deal with natural and dignified buauty care. 9. Accesaries (hat, handbag, handkerchief, gloves) change with fashion of clothes, it rapid more than clothes fashion. 10. On encouragement of abolition of white clothes and putting on dyeing clothes, because of economic defect of white clothes, psychology and beauty consequently, white clothes is on the rise abolition. In national level almost substitute dyeing clothes for control and improvement of people of all social standings consequently, dress and its ornaments conditions in those days analyzed account of Dong-A II Bo accept the foreign clothes that introduced internal country of the whole century, and substitute dyeing for white clothes. Costume condition in those days appear the mixed conditions of Korean clothes and Foreign clothes. In the 1920's is the first consideration dress and its ornaments form of Korean clothes. As later goes on foreign is given much weight in the whole clothes life. Account of foreign clothes managemental ways appear in the 1920's, while those facts prove the point that appeared the account that always dealed with concrete content of foreign fashion in the 1930's.

• Journal of Korean Society of Forest Science
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• v.87 no.4
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• pp.519-527
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• 1998

An economic study of vegetation control to increase production of Songyi (Korean name far pine mushroom, matsutake, Tracholoma matsutake (S. Ito & Imai) Sing.) in red pine (Panes densiflora) stands in Korea was undertaken. In Korea, Songyi grows only in red pine stands. Harvest of this mushroom provides a significant income source to rural people in Korea yielding exports of US$20 million to US$80 million per year. However, hypogeous Songyi colonies and the mushroom production are declining, partly because shade tolerant species are succeeding the shade intolerant red pine. Past research says that it is possible to deep Songyi production increasing by controlling under-story vegetation. But few people are wilting to invest in the necessary control. Our analysis found that the economics of vegetation control appear to be quite favorable, showing an internal rate of return (IRR) of 20.7 percent in 15 years. However, positive returns do not occur for at least eight years and even then, the returns may not appear to the landowner to be a result of vegetation control efforts only because the mushroom production has been greatly variable depending on weather conditions. In a sensitivity analysis, it was found that the number of circular mushroom colonies was critically important for the cash flow. Results of this analysis are also sensitive to assumptions about annual growth length(0.16m radial growth=1.0m/circular length growth) of Songyi colony. However, the primary goal of vegetation control should be to keep the young colonies growing. Further research in the behavior of hypogeous Songyi colonies after vegetation control would help to improve our confidence in the results.