• Title/Summary/Keyword: light condition

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Changes of Moisture Uptake. Respiration and Chemical Contents in Germinating Tobacco(Nicotiana tabacum L.) Seeds (담배종자의 발아조건에서 수분흡수, 호흡 및 저장물질의 변화)

  • 민태기;윤경은;김웅주;강정용
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.31 no.3
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    • pp.293-298
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    • 1986
  • The physiological aspects of tobacco seeds from seeding to germination under light and dark condition, and different temperature were studied to obtain basic information on the production of good seedlings. There were distinct three phases in moisture uptake and respiration process during germination that classifiable into 'Imbibition', 'Lag', and 'Growth' phase under light condition but such growth phase were not observed in the dark germination. Great changes of sugar and fatty acid content of tobacco seeds were observed during germination in light condition but such changes were slight in dark germinated seeds and fatty acid content of seeds during germination were decreased as corresponding to increasing in respiration.

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Impact Collapse Behavior of Hybrid Circular Thin-walled Member by Stacking Condition (적층조건에 따른 혼성 원형 박육부재의 충격압궤거동)

  • Lee, Kil-Sung;Park, Eu-Ddeum;Yang, In-Young
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.19 no.2
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    • pp.235-240
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    • 2010
  • The recent trend of vehicle design aims at crash safety and environmentally-friendly aspect. For the crash safety aspect, energy absorbing members should be absorbed with collision energy sufficiently. But vehicle structure must be light weight for the environmentally-friendly aspect, in order to improve fuel efficiency and to reduce tail gas emission. Therefore, the light weight of vehicle must be achieved in a status of securing safety of crash. An aluminum or CFRP (Carbon Fiber Reinforced Plastics) is representative one among the light-weight materials. In this study, impact collapse behavior of circular hybrid thin-walled member is evaluated. The hybrid members are manufactured by wrapping CFRP prepreg sheets outside the aluminum circular members in the autoclave. Because the CFRP is an anisotropic material whose mechanical properties change with its stacking condition, special attention is given to the effects of the stacking condition on the collapse behavior evaluation of the hybrid thin-walled member. Collapse mode and energy absorption capability of the hybrid thin-walled member are analyzed with change of the fiber orientation angle and interface number.

Changes in Isoflavones Contents and Germination Characteristics of Germinated Soybeans [Glycine max.] under Light Condition (명조건에서 발아시킨 콩의 발아특성 및 isoflavone함량 변화)

  • Choi, Seon-Jeong;Choi, Ung-Kyu
    • Journal of the Korean Society of Food Culture
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    • v.29 no.6
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    • pp.599-604
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    • 2014
  • This research was conducted to investigate changes in isoflavone contents and sprouting characteristics of germinated soybeans [Glycine max.] under light condition. The relative wet weight of soybeans increased as germination progressed, and it reached $291.1{\pm}14.3%$ at 60 h after beginning of sprouting. On the other hand, relative dry weight slowly decreased as germination progressed. The length of sprouting rapidly increased as germination progressed. The sprouting rate sharply increased from 12 h to 48 h and reached $96.4{\pm}2.5%$ at 60 h after sprouting. In terms of color, L value did not change until 24 h after the beginning of germination, but it rapidly increased from 24 h to 36 h and did not change thereafter. The a value rapidly increased at 24 h after the beginning of germination and decreased thereafter. The b value rapidly increased at early and last stages and reached $9.0{\pm}0.7$ at 60 h after the beginning of sprouting. Total isoflavone reached a maximum level at 12 h after the beginning of germination and consistently decreased thereafter. Among isoflavone compounds, m-genistin had the highest content followed by daidzin and m-daidzin.

Measurement of Aircraft Wing Deformation and Vibration Using Stereo Pattern Recognition Method (스테레오 영상을 이용한 비행 중인 항공기 날개의 변위 및 진동 측정)

  • Kim, Ho-Young;Yoon, Jong-Min;Han, Jae-Hung;Kwon, Hyuk-Jun
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.25 no.8
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    • pp.568-574
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    • 2015
  • The present study was conducted by using stereo pattern recognition method(SPR method) to measure the displacement and vibration of an airplane wing in flight condition. A SPR based measurement system was developed using two visible light stereo cameras. The visible light stereo images were processed to obtain marker points by adaptive threshold method and marker filtering technique. The marker points were used to reconstruct 3D point, displacement, and vibration data. The SPR system was installed on F-16 fighter. The wing displacement and vibration were measured in flight condition. Therefore, this paper presents a possibility that SPR based measurement system using visible light stereo camera can be very useful for measuring displacement and vibration of an airplane in flight condition.

Plant Regeneration and Bulblet Formation of Allium wakegi Araki

  • Song, Won-seob;Yang, Deok-Chun;Yoon, Jae-Ho;Ryu, Sang-Hyun
    • Plant Resources
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    • v.7 no.1
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    • pp.7-14
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    • 2004
  • Allium wakegi was cultured shoot tip in the condition of light culture. The Allium wakegi added plant growth regulator was observed of plant regeneration and bulblet formation. Callus Induction and growing rate was the best of 78% when added alone 2,4-D 0.5mg/L. In the formation of shoot, its regeneration rate was 96% when added BA 0.5mg/L in the light culture condition. When BA 0.5mg/L and NAA 0.5mg/L mixed and BA 0.5 mg/L and NAA 1.0mg/L mixed, the rates were 99% and 97% respectively, and these conditions were suitable for forming shoot. In the formation of roots, when added NAA 2.0mg/L in the light culture condition, the regeneration rate was 90.6 % and the roots were abnormal. When added NAA 1.0mg/L, the rate was 82 % and the highest. In the formation of bulbs, when BA 05mg/L and NAA 1.0mg/L mixed, the root generantion and its size in the bulbs was the best compare to other treatment experiments.

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The Effects of Visible Light on Iron Release from Ferritin Related to Lipid Peroxidation in the Retina

  • Ohishi, Kentaro;Hiramitsu, Tadahisa;Matsugo, Seiichi
    • Journal of Photoscience
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    • v.9 no.2
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    • pp.427-429
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    • 2002
  • We studied iron release from ferritin by irradiating the visible light, and then followed ferritin-mediated lipid peroxidation in the rod outer segment (ROS) fraction of the porcine retina. In the presence of several phosphorus compounds such as ADP and ATP, iron release from ferritin at pH 7.0 could be induced by irradiation of the visible light to the reaction mixtures. Furthermore, iron release from ferritin in the presence of ADP depended on the incubation time and the visible light irradiation. Moreover, we investigated lipid peroxidation level in the ROS fraction by two independent assay systems including the thiobarbituric acid (TBA) and ferrous oxidation/xylenol orange (FOX) methods. The visible light induced ferritin-mediated lipid peroxidation in the ROS fraction in time- and irradiance-dependent manners. In the dark condition, iron release and lipid peroxidation were not observed. Iron release from ferritin by irradiating the visible light may play an important role in the etiology of phototoxic injuries in vivo.

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Wear Of Resin Composites Polymerized By Conventional Halogen Light Curing And Light Emitting Diodes Curing Units (HALOGEN LIGHT CURING UNIT 과 LIGHT EMITTING DIODES CURING UNIT 을 이용하여 중합되어진 복합레진의 마모 특성 비교)

  • 이권용;김환;박성호;정일영;전승범
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2004.10a
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    • pp.1057-1060
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    • 2004
  • In this study, the wear characteristics of five different dental composite resins cured by conventional halogen light and LED light sources were investigated. Five different dental composite resins of Surefil, Z100, Dyract AP, Fuji II LC and Compoglass were worn against a zirconia ceramic ball using a pin-on-disk type wear tester with 15 N contact force in a reciprocal sliding motion with sliding distance of 10 mm/cycle at 1Hz under the room temperature dry condition. The wear variations of dental composite resins were linearly increased as the number of cycles increased. It was observed that the wear resistances of these specimens were in the order of Dyract AP > Surefil > Compoglass > Z100 > Fuji II LC. On the morphological observations by SEM, the large crack formation on the sliding track of Fuji II LC specimen was the greatest among all resin composites. Dyract AP showed the least wear with few surface damage. There is no significant difference in wear performance between conventional halogen light curing and light emitting diodes curing sources. It indicates that a light emitting diodes (LED) source can replace a halogen light source as a curing unit for composite resin restorations.

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A Study on the Stabitity and Dyeing Condition in the Curcuma Longa L. (울금의 색소 추출과 안정성에 관한 연구)

  • 소황옥
    • Journal of the Korean Society of Costume
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    • v.39
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    • pp.79-89
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    • 1998
  • This study was carried out the effect of stability and color extract for it's condition in the curcuma L.. dyeing. The stability is to investigate the absorbance of the curcumin, one of the major yellow pigments and the stability regarding the effect of light, oxygen temperature and pH. The dyeing condition is compared the effect of mordanting condition and the best way to extract pigment and analysed through the color-fastness rating, color-difference value test. The main results obtained are summarized as follows ; 1.The best and proper solvent to extrect curcumin pigment was a ethanol and a distilled water. 2. The light effect indicated that the absorbances of solution in absence of ligh was more stable. 3. The oxygen(O2) effect to curcumin show-ed that the condition in the absence of O2 was more stable than that in presence of O2 4. The temperature showed that the absorbnace was best stable in4$^{\circ}C$ and less changed at $25^{\circ}C$ 5. The curcumin-etanol solution was stable in pH 2~4. 6. Generally color-fastness rating to silk, wool and cotton indicated that crocking C.F. and perspiration C.F. were more than 3rd grade and dry cleaning C.F. was more than 4th grade. But light color-fastness and washing color-fastness were very poor. 7. To make good color fastness, the mordan-ting treated group and the pre-mordant conditions were more effective than others 8. When compared with color-difference value test indicated that the silk was looks like more reddish and bluish color and than the wool and cotton were greenish and bluish. As a mordant, A(C2H4OH(COOH3) and D(K2Cr2O7)were more effective to make green-ish color in the silk and the reddish color was abtained by B(Al.K(SO4)2.12H2O) and C(FeSO4.7H2O).

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Effect of Prechilling and Alternating Temperature on Seed Germination of Native Plants (저온습윤 및 변온처리가 자생식물의 종자발아에 미치는 영향)

  • 강치훈;김두환
    • Korean Journal of Plant Resources
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    • v.13 no.3
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    • pp.202-207
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    • 2000
  • This study was conducted to investigate the characteristics of seed germination pattern by the prechilling and alternating temperature treatments to 16 species of native plant. The seed length, width and thickness ranged from 1.1 to 8.9 mm, from 0.7 to 7.5 mm and from 0.4 to 1.7 mm, respectively. In addition, the 1,000 grain weight of native plants ranged from 0.1 to 8.8g. Germination rate of Melandryum firmum R. and Saussurea pulchella F. with light condition, Capsella bursa-pastoris L. and Leonurus sibiricus L. with dark conditionin of non-treatment were the highest 69, 81,16 and 36%, respectively. Germination rate of Aster scaber T., Cirsium setidens N., Ligularia fischeri T., Plantago asiatica L., and Saussurea sp. of 5$^{\circ}C$ prechilling for 30 days were the highest 84, 29, 29, 57, 78 and 95% with light condition respectively, 30% but Cirsium nipponicum M. only with dark condition. Germination rate of Aralia elata S., Aster koraiensis N. and Synurus deltoides N. of alternating temperature with 8 hours at 3$0^{\circ}C$ and 16 hours at 15$^{\circ}C$ were the highest 2 and 57% with light condition and 52% with dark condition.

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Study on the Effect of Light Emitting Diode Irradiation on Improving Skin Condition (Light Emitting Diode 조사가 피부상태 개선에 미치는 효과 연구)

  • Lee, Jung-Hee;Ha, Sung-Yi;Moon, Ji-Sun
    • Journal of the Korean Applied Science and Technology
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    • v.37 no.6
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    • pp.1798-1805
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    • 2020
  • This study attempted to numerically verify specific effects on skin condition improvement by measuring and comparing changes in skin conditions such as pores, wrinkles, and sebum of LED masks for beauty devices with low output among light sources. 18 healthy women (4 weeks in the control group and 4 weeks in the experimental group) were conducted once a week for 8 weeks. As a result of measuring the skin condition of pores, wrinkles, and sebum, it was confirmed that the skin condition improved significantly as the LED irradiation progressed, and the difference between the groups by measurement period of the experimental group and the control group also showed significant differences in pores, wrinkles, and sebum (p< .001, p<.05). This is meaningful in that it can be presented as clinical information and quantitative data by preparing continuous data in an academic sense by proving the effect of improving the LED mask as a beauty device. It is also suggested that in the future, follow-up studies to prove more effective skin improvement will be conducted.