• 한국약용작물학회지
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• 제23권1호
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• pp.43-48
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• 2015

This study was carried out in order to investigate the photosynthesis response and leaf characteristics of Peucedanum japonicum growing in forest farming. The experiment was performed by leaf mold (pine tree and chestnut tree) and shading levels (0%, 35%, 50% and 75% shading). Light relative intensity was 100% (full sunlight), 60.3% (35% shading), 35.1% (50% shading), and 17.4% (75% shading) respectively. Light response curves of pine-leaf mold and chestnut-leaf mold were the highest in control (full sunlight) and these were getting lower in the higher shading level. Photosynthesis capacity and light saturation point were indicated higher in chestnut-leaf mold within the same shading level. As the shading level increased, maximum photosynthesis rate decreased. And apparent quantum yield was not indicated statistically significant difference from all treatment. Leaf area, leaf length and leaf width were significant higher in 35% shading and control under chestnut-leaf mold in all treatment. As the shading level increased, LAR (leaf area ratio), SLA (specific leaf area) and SPAD value decreased in pine-leaf mold and chestnut-leaf mold. As a result of surveying the whole experiment, P. japonicum is judged better growth and higher yield by maintaining 35% shading (relative light intensity 60%) under chestnut-leaf mold in forest farming.

• 한국환경복원기술학회지
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• 제7권3호
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• pp.73-77
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• 2004

차즈기의 관상가치 증진 및 광도에 따른 생육반응을 알아보기 위하여 실험을 실시한 결과 차광정도에 따라 생육상태가 매우 다르게 나타났다. 초장, 수관폭, 엽병장, 엽장, 엽폭, 줄기굵기, 건물중 등 대부분이 30% 차광 시에 높게 나타나 생육이 가장 좋았으며, 차광율이 높아질수록 모두 감소하였다. 엽록소함량도 30% 차광시에 가장 높았으며, 안토시아닌함량의 경우 70% 차광시에만 감소하였을 뿐 나머지 처리구에서는 큰 차이가 없었다. 또한 70% 차광 시에는 엽색이 암자적색에서 황록색으로 변하였고, 생육이 저조하였을 뿐만 아니라 식물체가 도복하여 차즈기 고유의 관상가치가 떨어지는 결과를 보였다.

• KIEAE Journal
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• 제13권4호
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• pp.21-26
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• 2013

Shading devices have become an integral part of the daylighting strategy for sustainable classroom design. The louver type is newly designed shading devices which provide more view to the outside and protect from outside condition such as snow or rain. The purpose of this study is to compare the daylight performance of traditional and louver type overhang and lightshelf. The room dimension was $7.5m{\times}9.0m{\times}3.0m$. The length of shading devices was calculated by Palmero's study. The length of the traditional and louver type overhang was 455mm, 1210mm and lightshelf was 350/810mm, 625/555mm respectively. For the study, the Radiance 2.0 was used to evaluate the illuminance and uniformity ratios. And scale model were used to evaluate sunpatch area on the floor in model was calculated. The results showed that the louver type lightshelf was suitable for spring and summer, and louver type overhang was suitable for winter.

• 원예과학기술지
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• 제17권1호
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• pp.29-32
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• 1999

본 연구는 차광수준이 송악과 수호초의 생육에 미치는 효과를 알아보기 위해 차광수준을 입사광의 0, 35, 55, 75, 그리고 95% 수준으로 실시하였다. 송악은 95%에서 생육이 억제되었으며 직립형의 성질을 나타냈고, 수호초는 35%에서 초장이 가장 높게 나타났다. 분지수는 차광수준에 따른 차이를 보이지 않았으며, 줄기의 직경과 초장은 35%부터 95%로 차광률이 높아지면서 감소하였다. 잎의 생장은 35%와 55% 차광수준에서 가장 좋았으며, 75%에서도 생육이 좋아서 내음성이 양호한 것으로 생각되었다. 잎은 광도가 감소함에 따라 길어졌으나, 95% 차광시에는 대조구보다 짧게 나타났다. 전체 엽록소, 엽록소 a, b 함량 및 엽록소 a/b 비율은 차광에 의해서 대조구보다 다소 증가하는 경향을 보여서, 95% 차광에서 가장 높게 나타났다. 생체중과 건물중은 35, 55, 75% 수준에서 대조구나 95% 차광수준에서보다 높았다. 비엽중은 광도가 감소함에 따라 감소하는 경향을 나타내었다. 이상의 결과로부터, 송악과 수호초의 생육에 적합한 광도는 35%~55% 차광수준이며, 75% 차광하에서도 생육에는 지장이 없을 것으로 보인다.

• 한국태양에너지학회 논문집
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• 제25권2호
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• pp.27-33
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• 2005

To improve the performance of the top-positioning space in buildings, we suggested the environment-friendly system integrating various design techniques in the previous paper. This work discussed to calculate the length of PV considering a part of metallic radiators for radiative cooling, an critical element of the whole system, for shading not to prevent the PV on roof from generating electricity. In the process of calculating the shading area, we used the geometrical relationship between the sun-rays and the variable roof. For general applications, we utilized DL, the ratio of the length of PV and that of metallic radiator on roof, as a design factor, and then used the maximum insolation and the specific insolation($200W/m^2$) to decide the distance off the axis of rotation. As a result, for DL, we found out the reasonable value of 1.0 with full covering, 1.2 with 90%, and 2.0 with 70% in PV covering.

• 한국작물학회지
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• 제69권1호
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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.

• 한국공간구조학회논문집
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• 제19권2호
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• pp.83-90
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• 2019

Most of the variable shading devices are installed outdoors, so they are greatly affected by structural safety due to external climate change, wind, rain, and snow. Especially, due to strong wind such as typhoons, safety problems may occur due to the dropout of the device. Therefore, it is necessary to secure the structural safety against the wind. Therefore, it is necessary to analyze the structural behavior of the windshield to evaluate the structural safety of the variable sunshade device. In this study, we analyze the wind pressure applied to the shading material according to the change of the length of the variable shading device, and apply it to the calculation of the wind load for the structural design of the variable shading device. The CFD (Computational Fluid Dynamic) analysis of the structure of the sample was used to analyze wind pressure magnitude and distribution. In order to estimate the wind pressure, the maximum wind loads of the static and negative pressures acting on the structure were analyzed from numerical simulation results.

• 한국약용작물학회지
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• 제9권1호
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• pp.1-7
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• 2001

가시오갈피(Eleutherococcus senticosus ssp.)은 항암작용, 항스트레스, 간기능 및 면역활성, 강정, 강장 등에 약효가 탁월하다고 알려져 있으며, 가시오갈피는 오갈피속 중에서 그 효능이 가장 우수한 식물로 건강식품으로의 자원개발(資源開發) 가능성이 높으나 해발 600m 이상의 고산지대(高山地帶)에서 자생(自生)하는 식물로 번식(繁殖) 및 재배(栽培)가 어려운 대부분 원료를 수입에 의존하고 있으나, 최근 국내산 가시오갈피가 세계에서 品質이 가장 우수한 것으로 알려지면서 그 수요가 점차 증가하고 있다. 따라서 강원도농업기술원 북부농업시험장에서는 $1998{\sim}1999$년 2개년에 걸쳐 차광처리(遮光處理) 및 시기(時期), 방법(方法), 수확적정(收穫適正) 높이 등에 관한 일련(一連)의 재배기술(栽培技術) 실험(實驗)을 수행(遂行)하였던 결과(結果)를 요약하면 다음과 같다. 1. 차광망(遮光網) 처리에 따른 환경조건(環境條件)은 무차광에 비해 차광망 $30{\sim}70%%처리시 광투과율은 $40{\sim}64%$, 온도(溫度)는 $1.9{\sim}2^{\circ}C$을 각각(各各) 낮출 수 있었다. 2. 가시오갈피의 평지(平地) 재배시(재배시(培時) 차광망처리에 따른 생육은 차광 50%에서 무차광에 비해 수고 48cm, 신초장(新草長) 27.8cm 가장 길었으며, 10a당 수량(收量)이 202.2kg으로 80.8kg 증수(增收) 효과(效果)가 있었다. 3. 가시오갈피 평지재배시(平地栽培時) 차광처리는 $7{\sim}8$월의 고온기(高溫期)에도 생육(生育)이 지속적(持續的)으로 이루어짐을 알 수 있었다. 4. 차광방법별(遮光方法別) 생육(生育)은 터널식 차광방법이 병풍식 차광보다 일조시간이 짧았으며, 생육이 양호(良好)하여 효과적인 방법(方法)으로 사료(思料)되었다. 5. 수확방법(收穫方法)(예취 높이별)에 따른 생육효과(生育效果)는 지면으로부터 높이 30cm, 부위 $2{\sim}3$마디에서 수확(예취)하는 것이 분지주(分枝株)의 길이, 수고(樹高), 수량(收量)이 높았으며, 차년도 생육(生育)이 양호하였다.

• 한국항해학회지
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• 제6권2호
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• pp.35-55
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• 1982

The attempt of this paper is to examine the basic theory on the analysis of the effect of a shading coil fitted to an electromagnetic contactor, and to compare experimentally the attracting force of an AC electromagnetic contactor with that of a DC electromagnetic contactor, with varying the airgap length. Equations are also proposed for calculating the AC and DC attracting force per unit consumption wattage by using the circuit constants measured from the experiment, and these calculated attracting forces are compared with those actulally measured, and then, the experimental contactor is examined in the view of its design. The calculated attracting forces are appeared to coincide well with the measured ones and the experimental contactor fitted with shading coil is revealed not so well designed for reducing the fluctuation of the attracting force.

• 한국환경복원기술학회지
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• 제11권6호
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• pp.104-111
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• 2008

Plant growth and variegated leaf color changes of three leaf variegated Sedum spectabile varieties 'Variegatum', 'Frosty Morn', red colored 'Washfield Ruby', and one Sedum lineare variety 'Variegatum' and Sedum sarmentosum under three levels of shading conditions were examined for leaf ornamental value improvement. Shading levels were 40%($1,500{\mu}mol{\cdot}m-^2{\cdot}s-^1$), 70%($750{\mu}mol{\cdot}m-^2{\cdot}s-^1$) and 85%($375{\mu}mol{\cdot}m-^2{\cdot}s-^1$). Improvements of leaf ornamental value of 'Variegatum' 'Frosty Morn' and 'Washfield Ruby' were observed at 40% shading level and plant heights and leaf sizes were also increased. Plant height of S.sarmentosum were shorten under direct sun light condition and leaf color changed to greenish yellow(RHS143B) but deep green color(RHS144A) was observed under shading conditions. Endurance of S.sarmentosum was stronger than other species and leaf ornamental values remained well at 70% shading level. Leaf width of S.lineare 'Variegatum' were not changed under shading conditions but leaf length was increased. Leaf color was Deep green color was greenish yellow under direct sun light but deepest green color was observed at 85% shading level. Consider all ornamental value criteria, best shading conditions for S.lineare 'Variegatum' were ranged 40% to 70%.