• Journal of Korean Society of Steel Construction
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• v.19 no.2
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• pp.171-179
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• 2007

The greenhouse discrete optimum design program was developed using discrete optimum algorithm based on the genetic algorithm. The basic search method for the optimum design is the genetic algorithm, which is known to be very efficient for discrete optimization. In this paper, the objective function was the weight of the greenhouse structures and the constraints were the limits state design method. The design variables were galvanized steel pipes for plastic housing KSD 3760. Objective criteria were presented for the design of economic greenhouse structure and evaluation of its stability. The standardizations of greenhouse structure were used, as well as the normalization of greenhouse-related materials. Design examples were given to show the applicability of the optimum design using the discrete optimum algorithm based on the genetic algorithm of this study.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 1997.11a
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• pp.1-7
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• 1997

온실이란 식물 생육에 요구되는 태양광을 유용하게 활용하기 위하여 투명한 피복재가 사용된 구조물을 일컫는다. 온실내로 투과되는 일사량은 온실이 설치된 지역의 위도, 온실의 동방위 및 형상, 구조물의 재원, 피복재의 광학적 특성, 년중일수, 기상 조건, 지붕면의 경사각 등에 따라 변화된다. 일반적으로 겨울철에 온실내의 일사량은 식물의 정상적인 생육에 제약이 되는 요소로 작용한다. (중략)

• Journal of Korean Association for Spatial Structures
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• v.10 no.2
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• pp.61-68
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• 2010

The collapsing accidents of pipe greenhouses in the farmhouse have been increased duo to heavy snow load. However, the study on exact structure analysis to prevent the collapse of pipe greenhouses is rare and the damage of the farmhouse is annually repeated. The method of existing structure analysis is basically made of linear elastic analysis based on the micro displacement. But the actual stiffness of the pipe greenhouse is significantly weaker than the stiffness of buildings and the load acting on the greenhouses gets to become relatively bigger. It means that the geometry shape of greenhouses changes so that the relation of strain-displacement gets to indicate a nonlinear behavior. Therefore, this study is performed to evaluate the structural safety so as to prevent the collapse of pipe greenhouses, which are the single-span greenhouse(farmhouse guidance shape, G) and multi-span greenhouse(farmhouse supply shape, 1-2W), by performing the large-displacement analysis considering nonlinear effects.

• Environmental and Resource Economics Review
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• v.20 no.2
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• pp.229-254
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• 2011

In this paper, we decomposed Greenhouse-Gas emissions of Korea's manufacturing industry using LMDI (Log Mean Divisia Index) method. Changes in $CO_2$ emissions from 1991 to 2007 studied in 5 different factors, industrial production (production effect), industry production mix (structure effect), sectoral energy intensity (intensity effect), sectoral energy mix (energy-mix effect), and $CO_2$ emission factors (emission-factor effect). By results, the structure effect and intensity effect has a role of reducing GHG emissions and The role of structure effect was bigger than intensity effect. The energy mix effect increased GHG emissions and emission-factor effect decreased GHG emissions. By time series analysis, IMF regime affected the GHG emission pattern. the structure effect and intensity effect in that regime was getting worse. After 2000, in the high oil price period, the structure effect and intensity effect is getting better.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.30 no.1
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• pp.7-15
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• 2017

This paper presents the results of the parametric study to investigate the effects of several analysis modeling parameters such as support conditions, member connectivities and cable member stiffness on the main mode shapes and natural frequencies of a representative disaster resilient greenhouse structure. In addition, an ambient vibration test was performed on the representative greenhouse structure and its main mode shapes and natural frequencies were obtained. By comparing the experimental and analysis results, a proper analysis modeling method of the representative greenhouse structure was proposed.

• Journal of Bio-Environment Control
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• v.3 no.2
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• pp.128-135
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• 1994

Recently, regionally characterized greenhouses have been built every place around the country. These greenhouses insist of their higher performance by considering regional merits than the greenhouses without considering regional ones, but it is not clear. The purpose of this study was to make clear the characteristics of the regionally characterized greenhouses through the analyses of actual state and structural safety. The greenhouses were investigated and classified into wide span house, large pipe house, arched lattice house, wooden house, viniculture house, and domed pipe house. The frames of wide span house, arched truss house, viniculture house and domed pipe house were analyzed to be structurally stable under the design wind speeds and snow depths in recurrence intervals of 15 or 30 years, but large pipe house was a little unstable and required some reinforcements, and wooden house turned out to be unstable. In addition, foundations of all characterized greenhouses were stable against pull - out capacity under the design wind speeds in recurrence interval of 30 years.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 2002.11a
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• pp.289-292
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• 2002

최근들어 파이프 골조의 온실 구조는 해마다 강풍이나 적설 둥으로 인한 파손으로 막대한 경제적 손실을 입고 있으며, 이러한 피해는 환경조절 및 자동화 설비의 설치에 직접적인 영향을 주는 중요한 요인이므로 시설의 구조역학적인 연구가 지속적으로 이루어져야 한다. 그러나 국내에서는 1990년대 초반 온실의 구조안전 및 구조설계 기준 설정, 자재의 규격화 및 표준화에 관한 연구가 일부 수행된 바 있으나, 파이프 골조의 온실은 구조물로서의 공학적 설계나 유지관리에 대한관심이 부족하여 시설의 구조역학적인 연구가 거의 이루어지고 있지 않는 실정이다. (중략)

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 1998.10a
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• pp.55-62
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• 1998

온실내에서 직달 및 산란일사의 투과율은 온실이 설치된 지역의 위도, 온실의 동방위 및 형상, 피복재의 광학적 특성, 년중일수, 기상 조건, 지붕면의 경사각 뿐만 아니라 온실의 길이, 구조물의 크기 등에 따라 달라질 수 있다. 현재 국내의 기상 조건에 적합한 표준형 유리온실의 설계 기준이 부분적으로 제시되고 있으나, 온실내의 광환경과 관련된 설계 기준은 제시되지 않고 있는 실정이다. (중략)

• Journal of Bio-Environment Control
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• v.11 no.1
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• pp.45-49
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• 2002

온실에서 환기는 온실내외의 공기를 교환하여 온실내부의 환경을 조절하는 수단으로 활용되고 있으나 조절 목표는 한계가 있기 때문에 보조수단의 역할을 한다. 주년재배용 대규모 온실 설계시 해결해야 할 문제중의 하나가 여름철의 고온장해이며 이는 온실의 자연환기 성능과 밀접한 관계를 가지고 있다. 본 강좌에서는 온실의 자연환기에 관한 기본적인 내용을 요약하여 정리하고, 온실구조가 자연환기 성능에 미치는 영향을 파악하기 위하여 수치해석으로 온실의 필요환기량, 측창과 천창의 면적비와 온실 폭이 자연환기 성능에 미치는 영향을 분석하였다. 온실의 자연환기 성능을 향상시키기 위해서는 주어진 조건하에서 가능한 한 측창과 천창의 면적을 동일하게 설계해야 하고 주년재배용 대규모 온실에서는 폭이 대략 50m이상이 되면 자연환기성능을 기대하기 어렵기 때문에 유의해야 할 것으로 판단된다.

• Journal of Bio-Environment Control
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• v.23 no.2
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• pp.95-108
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• 2014

The objective of this study is to develop the plastic greenhouse models which are structurally safe under the weather condition of Seongju and have the dimensions suitable for oriental melon cultivation as well. To grasp the structural features of greenhouses in Seongju, the field survey was conducted on 406 farmhouses which included 2,068 greenhouses. The field survey showed that the roof shape of arch type accounted for the highest rate, but recently even span or peach type became more popular and the width and height of greenhouse tended to increase as the period of use was short. The relationship of the width, ridge height and eaves height were established based on field survey data. Using climate data of Gumi adjacent to Seongju, the regressions were determined for the design wind speed and design snow depth depending on recurrence period. To design the greenhouse models against weather disasters in Seongju, the optimal design loads are 23.7 cm of snow depth and $33.8m{\cdot}s^1$ of wind speed. As the design results, four models of single-span greenhouse, two models of double-span greenhouses including extension were developed.