• Title/Summary/Keyword: Half shade

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Effect of Light Intensity on Growth and Flowering of Several Korean Native Wild Flower Plants (자생화훼식물의 광도차에 따른 생육반응)

  • Lee, Jong Suk
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.4 no.1
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    • pp.52-56
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    • 2001
  • Experiment was performed to investigate the effect of light intensity on growth and flowering status of Korean native Dianthus superbus var. longicalycinus, Sedum middendorifianum, Hemerocallis aurantiaca, Iris ensata var. spontanea and Aquilegia buergeriana var. oxysepola for effective landscaping. Number of floret and flower stalk per a plant were markedly increased under full sun(about 100,000lux), and decreased with decreasing light intensity in all tested plants. This result indicate that it will be cultivated in the open for promote landscaping values. However, leaf area and plant height were more increased under half sun(22,000lux) than open(100,000lux) or shade(7,700lux) in all plants except Sedum middendorifianum. Especially, Hemerocallis aurantiaca had same number of shoot and leaf size, even if planted under shade condition to show a wide adaptation to various light intensities.

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Effect of Different Light Intensities on the Growth and Leaf Gas Exchanges in Miscanthus sinensis and Pennisetum purpurascens (참억새 및 수크령의 광도차에 따른 생육변화 및 가스교환에 미치는 영향)

  • Kwack, Hye Ran;Lee, Jong Suk
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.7 no.1
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    • pp.110-115
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    • 2004
  • This experiment was conducted to investigate the effect of light intensities on the growth responses, carbohydrate contents and the characteristics of leaf gas exchange in Miscanthus sinensis and Pennisetum purpurascens. The plant height and leaf length were increased to about 30% in the sun. However, those were reduced severely in the shade, and leaf necrosis was also observed. The representative growth index and the dry weight of 2 species were 50% higher than shade and the rate was reduced according to the decrease of light intensities. Total carbohydrate contents showed very similar changes to that of dry weight. However, any notable influences were observed at above the light intensities of 250~500${\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ in the half shade. The size of spikes and the earliest spiking appeared in the sun and the spike color was decolorized as decreased in light intensities, irrespective of species. Photosynthetic rate of 2 species was 2 times higher in the sun than those in the shade, and it showed the typical photoresponses of sun plant. Stomatal conductances and intercelluar $CO_2$ concetration showed similar changes to that of photosynthetic rate. On the contrary, vapor pressure deficit was increased more in the shade than in the sun.

Effects of Soil Moisture on the Growth of Acer Palmatum under Indoor Low Light Intensity (실내의 저광도하에서 토양수분이 단풍나무의 생육에 미치는 영향)

  • 윤지영;김민수
    • Journal of the Korean Institute of Landscape Architecture
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    • v.28 no.4
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    • pp.21-28
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    • 2000
  • This study is conducted to analyze effects of soil moisture on the growth of maple(Acer palmatum) under indoor low light intensity. Maples grew under three different light intensities such as sunny place(average 353.2W/$m^2$), half shade(average 7.7 W/$m^2$) and shade/(average 1.9W/$m^2$).Under half shady and shady condition, each 24 planters(2 maples planted in each planter) were used and divided into 3 groups treated with different watering points. Three levels of soil water potential were set for watering points, such as -200mbar, -300mbar or -500mbar. Under sunny condition, there were only group of 8 planters, as comparison. Watering was applied when soil water potentials reached -500maber. The results of plant growth experiment are as followed. 1. Under the shady condition, 32 maples died among 48 maples for 7 months. 9 maples survived, watered at soil water potential -200mbar, 5maples at -300mbar and 2maples at -500mbar. 2. Leaf water content ratios were higher under lower light intensity. For the cell wall became thinner under lower light intensity. 3. Maples in shady were easy to die due to having thin cell wall, therefore they were easy to loss the turgor pressure. 4. In case of half shady condition, the group, watered at soil water potential -200mbar, had much smaller amount of rootlet than -300mbar, because there were excessive soil water. The group, watered at soil water potential -500mbar, had smaller amount of rootlet than -300mbar and there was a remarkable difference in leaf water potential in spite of nearly same soil water potential, because leaves received the water stress under lower soil water potential. 5. When maples grew soundly, the leaf water potential was largely influenced by the soil water potential.

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A CLINICAL EVALUATION OF A BLEACHING STRIP CONTAINING 2.9% HYDROGEN PEROXIDE (2.9% 과산화수소를 함유한 부착형 미백제의 임상적 효능과 안전성에 관한 연구)

  • Park Eun-Sook;Seong So-Rae;Hong Seong-Tae;Kim Ji-Eun;Lee So-Young;Hwang Soo-Youn;Lee Shin-Jae;Jin Bo-Hyoung;Son Ho-Hyun;Cho Byeong-Hoon
    • Restorative Dentistry and Endodontics
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    • v.31 no.4
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    • pp.269-281
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    • 2006
  • This study evaluated the effectiveness and safety of an experimental bleaching strip (Medison dental whitening strip. Samsung medical Co., Anyang, Korea) containing 2.9% hydrogen peroxide. Twenty-three volunteers used the bleaching strips for one and a half hour daily for 2 weeks. As control group. the same strips in which hydrogen peroxide was not included were used by 24 volunteers with the same protocol. The shade change (${\Delta}E^{*}$, color difference) of twelve anterior teeth was measured using Shade Vision (X-Rite Inc., S.W. Grandville, MI, USA). Chroma Meter (Minolta Co., Ltd. Osaka. Japan) and Vitapan classical shade guide (Vita Zahnfabrik, Germany). The shade change of overall teeth in the experimental group was significantly greater than that in the control group (p < 0.05) and was easily perceivable. The change resulted from the increase of lightness (CIE $L^{*}$ value) and the decrease of redness (CIE $a^{*}$ value) and yellowness (CIE $b^{*}$ value). The shade change of individual tooth was greatest in canine. and smallest in central incisor. The safety of the bleaching strip was also confirmed.

Disturbance regime and tree regeneration in kwangnung natural forest (광릉 자연림에서의 교란체제와 수목의 재생)

  • Cho, Do-Soon
    • The Korean Journal of Ecology
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    • v.15 no.4
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    • pp.395-410
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    • 1992
  • Disturbance regime and tree regeneration were studied in kwangnung natural forest, an old-growth deciduous hardwood forest located in central korea. This forest is dominated by carpinus laxiflora, c.erosa, and quercus species. The area occupied by canopy gaps was 4.6% of the total forested area, and the mean size of canopy gaps was 92 $m^2$ with the maximum being 524 $m^2$. More than half of the gaps were less than four years old, and 3/4 of the gaps were created by death of only or two canopy trees, indicating the dominance of small-sized gaps in kwangnung forest. about half of the gap-makers were c. laxiflora, and another one third were quercus species. In contrast, the most frequent relacers were c. laxiflora while quercus species filled only 5% of the gaps, suggesting a future shift in tree species composition under the current disturbance regime. tree regeration was more conspicuous even in small gaps than non-gaps regardless of shade-tolerance of tree species, indicating the importance of gaps in tree regeneration.

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A Study on the Relationship between Factors Affecting Soldering Characteristics and Efficiency of Half-cell Soldering Process with Multi-wires (Half-cell 기반 multi-wires 접합 공정에서 접합 특성에 영향을 주는 요인과 효율의 상관관계 연구)

  • Kim, Jae Hun;Son, Hyoung Jin;Kim, Sung Hyun
    • Current Photovoltaic Research
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    • v.7 no.3
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    • pp.65-70
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    • 2019
  • As a demand of higher power photovoltaic modules, shingled, multi-busbar, half-cell, and bifacial techniques are developed. Multi-busbar module has advantage for large amount of light havesting. And, half-cell is high power module for reducing resistive losses and higher shade tolerance. Recently, researches on multi-busbar is focused on reliability according to adhesion and intermetallic compound between Sn-Pb solder and Ag electrode. And half-cell module is researched to comparing with full-sized cell module for structure difference. In this study, we investigated the factors affecting to efficiency and adhesion of multi-wires half-cell module according to wire thickness, solder thickness, and flux. The results of solar simulator and peel test was that peel strength and efficiency of soldered cell is not related. But samples with flux including high solid material showed high efficiency. The results of FE-SEM and EDX line scan on cross-section between wire and Ag electrode for different flux showed thickness of solder joint between wire and Ag electrode is increasing through solid material increasing. Flux including high solid material would affect to solder behavior on Ag electrode. Higher solid material occurred lower growth of IMC layer because solder permeate to sider of wire ribbon than Ag electrode. And it increased fill factor for high efficiency. In soldering process, amount of solid material in flux and solder thickness are the factor related with characteristic of soldered photovoltaic cell.

Studies on Development of Native Landscape Plants for Middle Area of Korea (중부지방 조경용 자생식물 소재의 개발에 관한 연구)

  • 방광자;이종석
    • Journal of the Korean Institute of Landscape Architecture
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    • v.21 no.1
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    • pp.63-82
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    • 1993
  • In the middle areas of South Korea, we collected 308 wild herbaceous species for studying the possibility of landscaping and, growing them at West in Yongin country of Kyunggi province. We observed their vegetative and flowering characteristic. And the result is as follow: 1. 76 species(24.7%) such as Hosta capitata, etc. of them are thought useful for flower-bedding or landscaping for park and ground-covering, while 94 species(30.6%) are regarded useful for ground-covering, potting and indoor-planting. They are Nepatica maxima and Thaliticum minus var. hypoleucum, etc. 46 species(15%) seems to be useful for flower-bedding, ground-covering and potting. 2. 264(85.7%) of all the observed species are for the enjoyment of their flowers, while 36 species(11.4%) for the enjoyment of their leaves, and 9 species(2.9%) for their fruit. They are Viburnum dilatatum, etc. 3. As for the relation of their habits to light conditions, 148 species(48%) grow int he full sun of more than 50,000Lux, 138 species(44.8%) usually in in the half shade of 20,000 to 30,000Lux, 15 species(4.9%) in the shade of some 10,000Lux, and 7 speciese grow either in the full sun or in the shde. 4. some species such as Wasabia koreansa, Allium succuliferum, Asterglehni, Ligulariafisheri, Ligularia stenocephala Epimedium koreanum are considered available as edible plants as well as ornamentals plants, and Houttuynia cordata. Saururus chinensis, Epimedium koreanum need to be further developed not only as ornamental plants but also medicinal plants.

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Studies on Ascorbic Acid contents in Persimmon leaves tea by different cooking methods. (조리방법에 따른 감나무잎차의 Ascorbic Acid 함량에 관하여)

  • 박재옥
    • Journal of the Korean Home Economics Association
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    • v.17 no.2
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    • pp.32-38
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    • 1979
  • The purpose of this experiment was to find out the contained quantity of ascorbic acid form persimmon tea. They were different according to the month when the persimmon leaves were picked, the way of cooking and the length of time spent after cooking. The results of experiment can be summarized as follows : 1. About the same contained quantities of ascorbic acid were obtained among the persimmon leaves picked in September and October, and small contained quatities of it were obtained among the persimmon leaves picked in November. Therefore it can be concluded that the persimmon leaves picked in September and October are better than the leaves picked in November for permision tea. 2. According to the way of cooking the contained quantity of ascorbic acid were different. When green leaves were washed and boiled for 1 monute and dried in the shade for 48 hours, the largest contained quantity of ascorbic acid were obtained. When they were steamed in the steam box for 1 minute and 30 seconds and dried in shade for 48 hours medium contained quantity of ascorbic acid were obtained . The contained quantity of ascorbic acid were decreased when green leaves were dried without boiling when green leaves were dried without boiling or when branches of leaves were taken away by hand and dried. 3. The contained quantity of ascobic acid were also different according to the length of time spent after cooking. After 15 minutes from cooking it began to increase and after 150 minutes it reached the highest degree. After this time it began to decrease. 4. the best fragrance, taste and color of the Persimmn Tea are found out, after steaming in the steaming box for one minute and half second and after drying in the shade for fourty-eight hours.

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A Study on the Design Criteria for Urban Small Parks (설계평가(設計評價)를 통(通)한 도시소공원(都市小公園)의 설계기준(設計基準)에 관(關)한 연구(研究))

  • Ahn, Kun Yong;Kim, Kwi Gon;Im, Seung Bin
    • Journal of Korean Society of Forest Science
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    • v.68 no.1
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    • pp.18-31
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    • 1985
  • Users' satisfaction and behavior at five mini parks in the central area of Seoul City were investigated under the encironmental design evaluation framework. The major findings are as follows; 1) The major user group is a student group with the ages ranging from 15 to 24. 2) Half of the users spend 20 to 60 minutes in these parks. 3) According to the multiple regression analysis, the variables related to the satisfaction in daytime are noise level, sunshine, plants, crowding, and surface slope, where those in nighttime are quality of surrounding buildings, turf area, lighting, shade, and sculpture or fountain. 4) According to the free response, the basic needs inmini parks are shade for rest and such amenity facilities as bench, trash basket, and drinking fountain. In addition to these basic needs, users prefer such visually pleasing objects as sculpture and fountain.

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Influence of light Regime on Nitrate Reductase Activity and Organic and norganic Solute Composition of Four Sedges (Carex spp.)

  • Choo, Yeon-Sik;Roland-Albert;Song, Seung-Dal
    • Animal cells and systems
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    • v.2 no.4
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    • pp.455-462
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    • 1998
  • A survey was conducted on the inorganic and organic solute patterns of plants in connection with nitrate metabolism according to different light regimes (1.9, 16.0, 91.5 $Wm^{-2}$). Besides measuring in vivo NRA, we also quantitatively analyzed ater-soluble inorganic ions, organic acids, low molecular weight carbohydrates, amino aciss and total N (% DW). Among 4 Carex species, C. pilosa is known as shade-adapted species and the others as half (C. gracilis) to full (C. rostrata & C. distans) light-adapted species. Compared to species adapted to high light intensity, shade-adapted C. pilosa showed reduced productivity under the highest light intensity. In general, nitrate and amino acid levels decreased at higher light intensity, while sugar and organic acid concentrations increased. In C. pilosa osmolality tended to rise with increasing light intensity, while in the other species it tended to fall. Under low light intensity, the drop in soluble carbohydrate contents is osmotically compensated for by an enhanced nitrate concentration. It is concluded that competition between nitrate and $CO_2$reduction for reductants and ATP from photosynthesis may have important ecological consequences for the adaptation of plants to low or high light conditions. Additionally, the patterns of ionic changes due to increased light intensities were essentially the same in all selected species, indicating similar characteristics of heir mineral ion and organic acid metabolism as well as in field-grown Carex species.

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