• Title/Summary/Keyword: Shading

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History of Disease Control of Korean Ginseng over the Past 50 Years (과거 50년간 고려인삼 병 방제 변천사)

  • Dae-Hui Cho
    • Journal of Ginseng Culture
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    • v.6
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    • pp.51-79
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    • 2024
  • In the 1970s and 1980s, during the nascent phase of ginseng disease research, efforts concentrated on isolating and identifying pathogens. Subsequently, their physiological ecology and pathogenesis characteristics were scrutinized. This led to the establishment of a comprehensive control approach for safeguarding major aerial part diseases like Alternaria blight, anthracnose, and Phytophthora blight, along with underground part diseases such as Rhizoctonia seedling damping-off, Pythium seedling damping-off, and Sclerotinia white rot. In the 1980s, the sunshade was changed from traditional rice straw to polyethylene (PE) net. From 1987 to 1989, focused research aimed at enhancing disease control methods. Notably, the introduction of a four-layer woven P.E. light-shading net minimized rainwater leakage, curbing Alternaria blight occurrence. Since 1990, identification of the bacterial soft stem rot pathogen facilitated the establishment of a flower stem removal method to mitigate outbreaks. Concurrently, efforts were directed towards identifying root rot pathogens causing continuous crop failure, employing soil fumigation and filling methods for sustainable crop land use. In 2000, adapting to rapid climate changes became imperative, prompting modifications and supplements to control methods. New approaches were devised, including a crop protection agent method for Alternaria stem blight triggered by excessive rainfall during sprouting and a control method for gray mold disease. A comprehensive plan to enhance control methods for Rhizoctonia seedling damping-off and Rhizoctonia damping-off was also devised. Over the past 50 years, the initial emphasis was on understanding the causes and control of ginseng diseases, followed by refining established control methods. Drawing on these findings, future ginseng cultivation and disease control methods should be innovatively developed to proactively address evolving factors such as climate fluctuations, diminishing cultivation areas, escalating labor costs, and heightened consumer safety awareness.

Change of Growth and Yield Characters in Rice at Different Transplanting Densities under Agrivoltaics (영농형 태양광 발전 시스템 하부 벼 재배 시 재식밀도별 생육 및 수량변화)

  • Woon-Ha Hwang;Min-Ji Lee;Jae-Hyeok Jeong;Hoe-Jung Jeong;Wan-Gue Sang;Seong-Yul Jang;Dong-Won Kwon;Woo-Jin Im;Heok-Jin Park;Ji-Hyen Lee
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.69 no.2
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    • pp.88-96
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    • 2024
  • Recently, interest in renewable energy development has been increasing to promote carbon-neutral policies. Agrivoltaic is a solar power generation facility with the potential to aid in meeting carbon-neutral policies. It has the advantage of generating electricity while farming takes place, but it also has the disadvantage of reducing crop yield and cultivation safety. We analyzed the rice yield, quality, and stem growth characteristics according to different transplanting densities under agrivoltaics. Under agrivoltaics, the number of rice panicles was reduced by the shading effect, but the reduction was lower under 60 hills than under 80 and 100 hills. Brown rice perfect ratio was increased under 60 hills under agrivoltaics. Brown rice yield did not differ significantly between 60 and 80 hills under agrivoltaics. However, stem dry weight by unit(mg/cm) in each internode showed highest under 60 hills compared to 80 and 100 hills under agrivoltaics. Therefore, 60 hill density was considered appropriate to ensure cultivation safety and yield when cultivated rice under agrivoltaics.

Effect of shield tunnel underpass construction on the upper existing pipeline

  • Zhen-Dong Cui;Zhang-Lin Zhu;Xuan-Yu Mi;Li Yuan;Zhong-Liang Zhang;Chen-Yang Zhao
    • Geomechanics and Engineering
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    • v.39 no.4
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    • pp.369-383
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    • 2024
  • The construction of the shield tunnel results in the deformation of the surrounding soil and the existing pipeline. It is important to analyze the deformation of the existing pipeline during the excavation of the tunnel. Based on the two-stage analysis method, the shear effect of pipeline due to the uneven settlement was considered and the deformation and internal force of existing pipeline due to the tunnel excavation were studied. The theoretical formulas were verified by the in-site monitoring. Compared with the theoretical calculation, the three-dimensional numerical simulation was established to simulate the deformation of the existing pipeline and the ground surface during the tunnelling. The effect of the Poisson's ratio, the tunnel diameter and the pipeline shading on the deformation of the existing pipeline were further investigated. The results show that the deformation curves of the pipeline and the ground surface conform to the Gaussian distribution, and the position above the axis of the tunnel experiences the maximum. When the excavation surface of tunnel crosses underneath the pipeline, the pipeline and the ground surface experience larger deformation and more subsidence, respectively. A certain amount of uplift is generated for the pipeline and the ground surface at ± 20 m away from the center line of the tunnel. The deformation of existing pipelines is affected by the tunnel excavation within its diameter range. The results can provide a reference for the design and construction of the shield tunnel underpass.

Spectrophotometric analysis of the influence to shade of zirconia core on the color of ceramic (지르코니아 코아의 색조부여가 전부도재관의 색조에 미치는 영향에 대한 분광측색분석)

  • Baek, Ki-Hyun;Woo, Yi-Hyung;Kwon, Kung-Rock;Kim, Hyeong-Seob
    • The Journal of Korean Academy of Prosthodontics
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    • v.46 no.4
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    • pp.409-419
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    • 2008
  • Statement of problem: At all times people have tried to fabricate tooth restorations using tooth colored materials. Recently, demands for esthetics, even in restorations requiring strength, has brought a revolution to dentistry and increased use of zirconia. The basic color of zirconia is white to ivory. The color can be partially adapted by veneering it with ceramic materials. However, it would be better if the substructure could already be adapted to the basic color shade of neighboring teeth. By adaptation to the basic shade, it can help to reduce the necessary layer thickness of the veneer ceramic to achieve the desired color. Purpose: The purpose of this study was to spectrophotometrically evaluate the influence of shading of zirconia core on the final shade of all-ceramic restorations using the CIE $L^{*}a^{*}b^{*}$ system. Material and methods: Core specimens (n = 20 per group) of Lava Frame Zirconia, KaVo Everest Zirconia, Digident CAD/CAM Zirconia were fabricated at 20 mm in diameter and 0.5 mm in thickness. Halves of each groups were shaded in A3 color. These core specimens were veneered with A3 porcelain of the recommended manufacturer at thickness of 0.5 mm. CIE $L^{*}a^{*}b^{*}$ coordinates were recorded for each specimen with a spectrophotometer (Model CM-2600d, Minolta, Japan) at 0.5 mm, 0.4 mm, 0.3 mm in thickness. Color differences were calculated using the equation ${\Delta}E^{*}=[({\Delta}L^{*})2+({\Delta}a^{*})2+({\Delta}b^{*})2]1/2$. Results: 1. In the case where porcelain layer has a thickness of 0.5 mm, Lava Frame Zirconia and KaVo Everest group did not show clinically perceived color difference, however Digident CAD/CAM Zirconia group showed clinically perceived color difference according to shade allowed on core. 2. When the thickness of porcelain layer decreased from 0.5 mm to 0.4 mm, Lava Frame Zirconia and KaVo Everest group did not show clinically perceived color difference, on the other hand Digident CAD/CAM Zirconia group showed clinically perceived color difference according to shade allowed on core. 3. When the thickness of porcelain layer decreased from 0.5 mm to 0.3 mm, clinically perceived color differences were observed from all three groups. Conclusions: Ziroconia system, which is possible to allow shade on core, are thought to be much more favorable to reproduce natural shade compared to systems that is impossible to give shade. Therefore, clinicians ought to choose adequate system for certain clinical situation by considering above specific character.

Modernist painting style in Disney animation (디즈니 애니메이션에 나타난 모더니즘 회화스타일 : 색, 형태, 공간을 중심으로)

  • Moon, Jae-Cheol;Kim, Yu-Mi
    • Cartoon and Animation Studies
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    • s.33
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    • pp.31-53
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    • 2013
  • In the early twentieth century, history of animation began by modern artists, they produced various experimental images with the newly invented film and cameras. Artists in the field of movie, photography, paintings and others manipulated images in motion. But as some animated movies won industrial success and popularity, they became the trend but experimental style of early animation preserved by so-called non-mainstreamers or experimental animators, counteracting commercialism. Disney animation also followed the trend by applying realistic Hollywood film style, the worse critics placed a low value on the animation and it tarnished the image, although it was profitable investment from a business standpoint. To make images realistic, they opened a drawing class that animators developed skills to imitate motions and forms from subjects in real life. Also some techniques and gizmos were used to mimic and simulate three dimensional objects and spaces, multiplane camera and compositing 3D CG images with 2D drawings. Moreover, they brought animation stories from fairly tales or folk tales, and Walt's personal interest in live-action movies, they applied Hollywood-film-like narratives and realistic visual, and harsh criticism ensued. On the surface early disney animations' potential seems to be weakened, but in reality it still exists by simplifying and exaggerating forms and color as modern arts. Disney animation employs concepts of the modernism paintings such as simplified shapes and colors to a character design, when their characters are placed together in a scene, that visual elements cause mental reaction. This modification gives a new internal experience to audiences. As conceptual colors in abstract paintings make images appeared to be flat, coloring characters with no shading make them look flat and comparing to them, background images are also appeared to be flat. On top of that, multi-perspective at background images recalls modernist paintings. This essay goes in details with the animation pioneers' works and how Disney animation developed its techniques to emulate real life and analyses color schemes, forms, and spaces in Disney animation compared with modern artists' works, in that the visual language of Disney animation reminds of impression from abstract paintings in the beginning of the twentieth centuries.

( Studies on the Grassland Development in the Forest II. Effect of fertilizer ievel on qrowth and dry matter yield of grass-clover mixtures grown under pine trees (임간초지 개발에 관한 연구 II. 임간혼파초지에서 3요소 시비수준이 목초의 생육과 수량에 미치는 영향)

  • Han, Y.C.;Park, M.S.;Seo, S.
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.5 no.2
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    • pp.136-142
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    • 1985
  • For better grassland development in the forest, this field experiment was carried out to investigate the effect of thirteen different fertilizer levels of nitrogen(N), phosphorus ($P_2O_5$) and potassium ($K_2O$) on the botanical composition, growth and dry matter yield of grass-clover mixtures grown under trees with 40-50% of shading level. This experiment was arranged as a randomized block design with replications, and performed on the experimental field in the suburban forest of Suweon in 1984. The results obtained are summarized as follows: 1. Plant height and cover degree of grasses found to be high with 28 and 42kg N fertilizer per 10a, while those were the lowest with zero and N-zero fertilizer levels. The degree of bare land after the fourth cut was also high in the low N level. 2. A significant higher degree of leaf green and chlorophyll content of leaf blade was observed in the plot of 28 and 42 kg N per 10a when compared with low N fertilizer plot. However, leaf decay and plant type of grasses tended to be a little poor as the high N was applied. 3. the regrowth plant length and dry weight of grasses after the first cut increased significantly with 28 and 42 kg N fertilizer. However, those showed slightly increased regrowth in the plot of zero and N-zero fertilizer levels. 4. The dry matter yield of grasses was higher with 28 and 42 kg N than that of low N fertilizer level. Higher yields were obtained in the plot of standard ($N-P_2O_5-K_2O$=28-20-24 kg/10a), 50% increase of $N,P_2O_5K_2O$ and N-50% increase, although there were no significant differences among three fertilizer levels. 5. Growth, botanical composition, regrowth and yield of grasses grown under pine trees were significantly influenced by N fertilizer level, regardless of $P_2O_5\;and\;K_2O$. The fertilizer level of $N-P_2O_5-K_2O$ was 28-20-24 kg per 10a for more forage production in the forest. Considering economic yield in this study, however, the optimum fertilizer level of N, $P_2O_5\;and\;K_2O$ was suppose to be 21-28, 10-15, and 12-18kg per 10a, respectively.

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In Vitro Evaluation of Shear Bond Strengths of Zirconia Cerami with Various Types of Cement after Thermocycling on Bovine Dentin Surface (지르코니아 표면 처리와 시멘트 종류에 따른 치면과의 전단 결합 강도 비교 연구)

  • Cho, Soo-Hyun;Cho, In-Ho;Lee, Jong-Hyuk;Nam, Ki-Young;Kim, Jong-Bae;Hwang, Sang-Hee
    • Journal of Dental Rehabilitation and Applied Science
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    • v.23 no.3
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    • pp.249-257
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    • 2007
  • State of problem : The use of zirconium oxide all-ceramic material provides several advantages, including a high flexural strength(>1000MPa) and desirable optical properties, such as shading adaptation to the basic shades and a reduction in the layer thickness. Along with the strength of the materials, the cementation technique is also important to the clinical success of a restoration. Nevertheless, little information is available on the effect of different surface treatments on the bonding of zirconium high-crystalline ceramics and resin luting agents. Purpose : The aim of this study was to test the effects of surface treatments of zirconium on shear bond strengths between bovine teeth and a zirconia ceramic and evaluate differences among cements Material and methods : 54 sound bovine teeth extracted within a 1 months, were used. They were frozen in distilled water. These were rinsed by tap water to confirm that no granulation tissues have left. These were kept refrigerated at $4^{\circ}C$ until tested. Each tooth was placed horizontally at a plastic cylinder (diameter 20mm), and embedded in epoxy resin. Teeth were sectioned with diamond burs to expose dentin and grinded with #600 silicon carbide paper. To make sure there was no enamel left, each was observed under an optical microscope. 54 prefabricated zirconium oxide ceramic copings(Lava, 3M ESPE, USA) were assigned into 3 groups ; control, airborne-abraded with $110{\mu}m$ $Al_2O_3$ and scratched with diamond burs at 4 directions. They were cemented with a seating force of 10 ㎏ per tooth, using resin luting cement(Panavia $F^{(R)}$), resin cement(Superbond $C&B^{(R)}$), and resin modified GI cement(Rely X $Luting^{(R)}$). Those were thermocycled at $5^{\circ}C$ and $55^{\circ}C$ for 5000 cycles with a 30 second dwell time, and then shear bond strength was determined in a universal test machine(Model 4200, Instron Co., Canton, USA). The crosshead speed was 1 mm/min. The result was analyzed with one-way analysis of variance(ANOVA) and the Tukey test at a significance level of P<0.05. Results : Superbond $C&B^{(R)}$ at scratching with diamond burs showed the highest shear bond strength than others (p<.05). For Panavia $F^{(R)}$, groups of scratching and sandblasting showed significantly higher shear bond strength than control group(p<.05). For Rely X $Luting^{(R)}$, only between scratching & control group, significantly different shear bond strength was observed(p<.05). Conclusion : Within the limitation of this study, Superbond $C&B^{(R)}$ showed clinically acceptable shear bond between bovine teeth & zirconia ceramics regardless of surface treatments. For the surface treatment, scratching increased shear bond strength. Increase of shear bond strength by sandblasting with $110{\mu}m$ $Al_2O_3$ was not statistically different.

Dynamics of Temperature and Humidity Changes in Lentinula edodes Sawdust Cultivation Sheds (표고 톱밥재배사의 溫-濕度 變化 動態)

  • Koo, Chang-Duck;Kim, Je-Su;Lee, Hwa-Yong;You, Sung-Ryul;You, Chang-Hyun
    • Journal of Korean Society of Forest Science
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    • v.98 no.6
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    • pp.748-756
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    • 2009
  • The key for cultivating Lentinula edodes in sawdust bags with an appropriate strain and medium is to encourage the mushroom growth, while discouraging contaminating fungi by controlling environment, especially temperature and relative humidity (RH). To investigate the daily and seasonal fluctuation of temperature and RH in two L. edodes cultivation sheds types, HOBO data loggers was set and the collected data were analyzed. In a Taiwan type L. edodes cultivation shed, temperature and humidity changes were divided into five characteristic periods: mycelium growing winter, mushroom fruiting spring, mushroom fruiting early summer, mushroom nonfruiting summer and mushroom fruiting autumn. First, the mycelium growing winter was December to early March with daily mean temperature of $-1{\sim}8^{\circ}C$. Second, mushroom fruiting spring was mid March to late May with daily mean temperature of $8{\sim}21^{\circ}C$ and day-night temperature difference of $15^{\circ}C$. Third, the Mushroom fruiting early summer was early June to early July with 17 to $25^{\circ}C$. Fourth, nonfruiting summer was mid July to mid August with daily mean temperature of $25{\sim}28^{\circ}C$. Lastly, mushroom fruiting autumn was late August to October with daily mean temperature of $10{\sim}23^{\circ}C$ and with cyclic temperature change by $7^{\circ}C$ decrease and 5 increase every 5 to 7 days. In a Chinese type shed, temperature ranged $-1.9{\sim}5.0^{\circ}C$ during winter and $15{\sim}32^{\circ}C$ during June to October. Temperature and relative humidity changed $12{\sim}30^{\circ}C$ and 40~100%, respectively, depending on 0~150 cm shelf heights of by positions in the shed. In conclusion, to grow L. edodes but to discourage contaminating fungi, that is, not to be too high in temperature and RH, the growers changed temperature and RH by adjusting shading, aeration and insulation in the shed.

Impacts of Three-dimensional Land Cover on Urban Air Temperatures (도시기온에 작용하는 입체적 토지피복의 영향)

  • Jo, Hyun-Kil;Ahn, Tae-Won
    • Journal of the Korean Institute of Landscape Architecture
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    • v.37 no.3
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    • pp.54-60
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    • 2009
  • The purpose of this study is to analyze the impacts of three-dimensional land cover on changing urban air temperatures and to explore some strategies of urban landscaping towards mitigation of heat build-up. This study located study spaces within a diameter of 300m around 24 Automatic Weather Stations(AWS) in Seoul, and collected data of diverse variables which could affect summer energy budgets and air temperatures. The study also selected reflecting study objectives 6 smaller-scale spaces with a diameter of 30m in Chuncheon, and measured summer air temperatures and three-dimensional land cover to compare their relationships with results from Seoul's AWS. Linear regression models derived from data of Seoul's AWS revealed that vegetation volume, greenspace area, building volume, building area, population density, and pavement area contributed to a statistically significant change in summer air temperatures. Of these variables, vegetation and building volume indicated the highest accountability for total variability of changes in the air temperatures. Multiple regression models derived from combinations of the significant variables also showed that both vegetation and building volume generated a model with the best fitness. Based on this multiple regression model, a 10% increase of vegetation volume decreased the air temperatures by approximately 0.14%, while a 10% increase of building volume raised them by 0.26%. Relationships between Chuncheon's summer air temperatures and land cover distribution for the smaller-scale spaces also disclosed that the air temperatures were negatively correlated to vegetation volume and greenspace area, while they were positively correlated to hardscape area. Similarly to the case of Seoul's AWS, the air temperatures for the smaller-scale spaces decreased by 0.32% ($0.08^{\circ}C$) as vegetation volume increased by 10%, based on the most appropriate linear model. Thus, urban landscaping for the reduction of summer air temperatures requires strategies to improve vegetation volume and simultaneously to decrease building volume. For Seoul's AWS, the impact of building volume on changing the air temperatures was about 2 times greater than that of vegetation volume. Wall and rooftop greening for shading and evapotranspiration is suggested to control atmospheric heating by three-dimensional building surfaces, enlarging vegetation volume through multilayered plantings on soil surfaces.

Studies on the grassland Development in the Forest IV. Possibility of the grassland improvement by spring sowing and microenvironmental conditions in the forest (임간초지 개발에 관한 연구 IV. 임간지에서 춘파초지개량 가능성과 주요 미기상 조사)

  • Park, M.S.;Han, Y.C.;Seo, S.;Lee, B.S.
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.6 no.1
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    • pp.31-37
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    • 1986
  • In order to study the possibility of grassland improvement by spring sowing in the forest, microenvironmental conditions, emergence, percentage of grasses and weeds, root weight and dry matter yield of grasses were investigated. Two field sites (forest grassland and full-sunlight grassland) and two sowing times (March 20 and April 10) were assigned. The condition of the forest grassland was area of pine trees with 50% shading, and the experiment was performed at the Livestock Experiment Station in Suweon, 1984. The results obtained are summarized as follows: 1. For germination and early growth of grasses, full-sunlight grassland was more advantageous than forest grassland. Growth after that stage, on the other hand, forest grassland was more suitable. Especially, during dry and high temperature season, temperature of soil surface and underground in the forest grassland were decreased by $6-7^{\circ}C$ and $3-4^{\circ}C$ each other, compared with those of the full-sunlight grassland. Also soil moisture content was continuously higher in the forest grassland. 2. At March 20 sowing the emergence time in the full-sunlight grassland was shortened by 8 days, compared with that of the forest grassland. In case of sowing on April 10, however, there was no difference between two grassland sites. 3. Grasses grown in the forest was more prostrate and leaves from them decayed more, compared with those of the full-sunlight grassland. 4. The percentage of grasses in the forest grassland was 80 to 85 %, on the other hand, that of the full-sunlight grassland was only 15 to 20 %. And the percentage of grasses tended to be high in the plot of early sowing time. 5. Dry root weight and root length of grasses grown in the forest were inferior to those of the full-sunlight grassland (P<0.05), but there was no significant difference between two sowing times. 6. Dry matter yield of grasses was significantly higher (P<0.05) in the forest grassland than in the full-sunlight grassland, and yield was influenced by sowing time. Higher yield (4,011 kg/ha) was produced in the plot of the forest grassland with early spring sowing. 7. From above results, it is suggested that grassland improvement by spring sowing in the forest is possible, and it is desirable to sow in early spring.

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