• Korean Journal of Medicinal Crop Science
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• v.28 no.2
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• pp.111-118
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• 2020

Background: Cnidium officinale is a medicinal crop sensitive to high temperature. It is necessary to develop environment control technology that can reduce environmental stresses such as high temperature. This study was conducted to develop technology for stable production of Cnidium officinale by reducing damage owing to high temperature by applying shading treatment of varying duration, and structure. Methods and Results: Black shading nets were used from May to September or November; shading structures such as pillar, flat roof, and tunnel type structures were installed. Environmental changes, rate of photosynthesis, and growth characteristics were investigated. The shading treatment reduced temperature by 3℃. The rate of photosynthesis and yield with shading treatment were higher by 134% and 127%, respectively, than those with full sunlight. The ratio of shading area ranged from 50% to 71% according to the type of shading structure. The effect of environmental control on growth varied depending on the type of shading structure. Conclusions: The shading treatment reduced damage owing to high temperature, shading rate of 55% - 75% was recorded between the period May - September, and the flat roof type shading structure was considered the most suitable among shading methods.

• Magazine of the Korean Society of Agricultural Engineers
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• v.45 no.4
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• pp.98-106
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• 2003

In order to set up structural improvement strategy against meteorological disasters of the shading structures in ginseng fields, structural safety analyses as well as some case studies of structural damage patterns were carried out. According to the results of structural safety analysis, allowable safe snow depth for type B(wood frame with single span) was 25.9 cm, and those for type A(wood frame with multi span) and type C and D (steel frame with multi span) were 17.6 cm, 25.8 cm, and 20.0 cm respectively. So types of shading structures should be selected according to the regional design snow depth. An experiential example study on meteorological disasters indicated that a strong wind damage was experienced once every 20 years, and a heavy snow damage once every 9.5 years. The most serious disasters were caused by heavy snow and it was found that a half break and complete collapse of structures were experienced by about 70% of snow damage. In addition to maintenance, repair and reinforcement, it is also recommended that improved model of shading structures for ginseng cultivation should be developed as a long term countermeasures against meteorological disasters.

• Journal of Korean Association for Spatial Structures
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• v.19 no.2
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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.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.35 no.5
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• pp.169-179
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• 2019

During the initial design stage of apartment complex, the photovoltaic(PV) system has been considered as an alternative of renewable energy system and planned to install at the rooftop floor level in general. The electric power generation characteristics can be influenced by the block layout, building orientation and roof top structure because of azimuth angle, tilt angle, and partial shading. This study aims to investigate power generation characteristics of photovoltaic system in apartment buildings by considering the partial shading conditions due to the block layout, building orientation and roof-top structures. For the photovoltaic module arrangement planning in rooftop floor level, shading areas were firstly analyzed due to the adjacent building structure. And the annual and seasonal power generation of PV system were analyzed through the PVsyst simulation results. The results show that shading period at the roof top surface can be increased due to the parapet and water tank. Initial design power capacity can be decreased by considering the daily insolation period and distance between PV modules through the shading simulation. As the number of PV modules decreases, the annual power generation can be decreased. However annual power generation per unit area of PV modules can be increased and performance ratio can be increased above 80%. Also the power generation of PV system can be critically affected by building orientation and the performance ratio can be drastically decreased in east-oriented buildings due to the shading problems caused by adjacent structures at roof top level such as parapet and water tank.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2002.10a
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• pp.65-68
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• 2002

This study was conducted to secure the structural safety and to build fundamental data for development of controlled environment facilities in ginseng cultivation. Shading structures of ginseng cultivation were classified with materials, structural forms, and detailed setups. They are wood or steel pipe, single or multi span, and frame or cable type. For structures having representative forms and dimensions, modeling for structural analysis was builded by SAP2000. And there was almost no farm carrying out the environmental management specially.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2008.10a
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• pp.153-156
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• 2008

According to the conversion of building into skyscraper, most buildings have curtain wall structures, so the shading device of building is required. The types of shading systems are a roller shade, venetian bind, and vatical blind and so on. A miler shade is mostly used among the shading systems. An experimental evaluation was verified whether there was an effect of shading materials(Perforated panel, Fabric) in each condition by an experiment with artificial lighting and daylight.

• Proceedings of the Korean Society of Crop Science Conference
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• 2001.05a
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• pp.198-199
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• 2001

• Journal of Ginseng Research
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• v.15 no.1
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• pp.31-35
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• 1991

In order to know the optimum planting density under shading structures at different light intensity, We investigated the growth status, distribution of ginseng leaf area, correlation between planting density and root weight per plant and yield, correlation between leaf area index and root weight per plant and yield. According to the increase of planting density the leaf area per plant was decreased, but leaf area index (L.A.I) was increased. Ginseng leaf population at different lines under common straw shading were distributed mainly in frost lines but polyethylene net shading at 10fo light intensity were distributed equally in all lines. Optimum planting density in common straw shading at 5% light intensity was 55 plant per tan (90 cmX180 cm) and polyethylene net shading 81 10% light intensity was 60 plant per tan, in consideration of root weight and yield. Optimum leaf area index was 2.4 under common straw shading at 5% light intensity but was 2.7 under polyethylene net shading at 10% light intensity.

• Journal of Bio-Environment Control
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• v.12 no.3
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• pp.114-120
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• 2003

In order to provide fundamental data for development of controlled environment facilities in Korean ginseng (Panax ginseng C.A. Meyer) cultivation, field survey and analysis of structural and environmental engineering characteristics on the shading structures in ginseng fields (the ginseng houses) were carried out. In this study shading structures for ginseng cultivation were classified according to their structural materials, connection types, and detailed structures. That is they were classified into wood or steel frames, single or multi spans, and frame or cable types. As a result of the investigation, standardization of structural materials, fabrication and construction methods arc required. And it was considered that a reinforced design and a countermeasure for heavy snow are the most important matters for structural improvement. In parts of the environmental management, researches for setting up the irrigation standard are required in the first place. And it was investigated that an installation of the shading structures is a work being the most hard, taking a lot of time, and having need for automation. So controlled environment ginseng houses, with a low cost, a structural safety and a satisfactory workability, should be developed.

• The Korean Ginseng Research and Industry
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• v.5 no.1
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• pp.22-35
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• 2011