• 한국식물생명공학회:학술대회논문집
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• 한국식물생명공학회 2005년도 추계학술대회 및 한일 식물생명공학 심포지엄
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• pp.367-370
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• 2005

The risk from genetically modified (GM) plants results from the possibility of gene contamination producing adverse effects on biological diversity by introducing herbicide or insect resistance into related plants or weeds (NAS 2002). The concern about the leakage of genes from GM plants into the environment has primarily focused on pollen that could be wind-borne for long distances. During the period of fisk assessment in Japan, physical containment is applied as a measure of reducing gene flow via the dispersal of pollen from GM plants into the surrounding environment In this study, we tried to estimate the effect of physically contained greenhouse covered by 1-mm fine mesh to reduce pollen dispersal by researching cross pollination rate between non-GM yellow maize in a greenhouse and silver maize outside the greenhouse.

• 한국생물환경조절학회:학술대회논문집
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• 한국생물환경조절학회 1999년도 학술발표논문집
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• pp.122-125
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• 1999

Ventilation is the primary method of controlling greenhouse air temperature, relative humidity, and carbon dioxide concentration. Two types of ventilation systems that are normally used are natural and fan. While fan ventilation is typically achieved with one wall as an inlet and the opposite wall as a fan outlet, natural ventilation is generally achieved by air exchanges that occur through multiple controlled openings due to natural pressure variations inside and outside the greenhouse. (omitted)

• 한국대기환경학회지
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• 제21권4호
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• pp.459-469
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• 2005

In recent years, concerns have been growing globally regarding greenhouse gases. Open burning of biomass causes emission of a number of greenhouse and other gases and substances. This paper studied an analysis on the characteristics of four types of biomass using duel type cone calorimeter. Cone calorimeter is widely used for assessing combustibility of materials in Europe. As a result, we evaluated several characteristics of biomass, such as heat released rate, smoke production rate, CO, $CO_2$ production and mass loss rate, and so on. $CO_2$ is currently responsible for over $60\%$ of the enhanced greenhouse effect, and may be the most important contributor to future. $CO_2$ production for biomass in the range of $1.74\~1.99kg/kg$ is similar to previous research conducted by Bhattacharya et al. (2002a).

• KIEAE Journal
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• 제11권2호
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• pp.67-74
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• 2011

Recently environmental regulations like the Kyoto Protocol, adopted in 1997, required the reduction of the greenhouse gas of 5.2% up to 1990's emissions and 13th General Assembly in 2007, held in Bali of India, have agreed to duty reduction even in developing countries in 2013. Korean government needs research on climate change and greenhouse gas management, such as carbon emissions calculation system and the introduction of greenhouse gas reduction program. Using Top-Down approach with method of IPCC, greenhouse gas emissions from energy, transportation, agriculture, land use and forest, and waste was calculated. Total amount from Shiheung-City in 2007 was about 3,299.581 tons of greenhouse gas $CO_2$. By sectors, the total greenhouse gas emissions in the energy sector mostly accounted for 78 percent, 12 percent from transportation, 6 percent of waste, the landuse/forest sector, 4% of the greenhouse gas emissions. Approximately 5,401,618 tons of the greenhouse gas $CO_2$ was total amount from Ansan-City in 2007. The share of energy sector greenhouse gas emissions was the highest portion of 79 % and 14 percent of transportation, 4% from the waste sector, 3 % from landuse/forest sector.

• 생물환경조절학회지
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• 제25권2호
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• pp.123-132
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• 2016

The importance of energy saving technology for managing greenhouse was recently highlighted. For practical use of energy in greenhouse, it is necessary to simulate energy flow precisely and estimate heating/cooling loads of greenhouse. So the main purpose of this study was to develope and to validate greenhouse energy model and to estimate annual/maximum energy loads using Building Energy Simulation (BES). Field experiments were carried out in a multi-span plastic-film greenhouse in Jeju Island ($33.2^{\circ}N$, $126.3^{\circ}E$) for 2 months. To develop energy model of the greenhouse, a set of sensors was used to measure the greenhouse microclimate such as air temperature, humidity, leaf temperature, solar radiation, carbon dioxide concentration and so on. Moreover, characteristic length of plant leaf, leaf area index and diffuse non-interceptance were utilized to calculate sensible and latent heat exchange of plant. The internal temperature of greenhouse was compared to validate the greenhouse energy model. Developed model provided a good estimation for the internal temperature throughout the experiments period (coefficients of determination > 0.85, index of agreement > 0.92). After the model validation, we used last 10 years weather data to calculate energy loads of greenhouse according to growth stage of greenhouse crop. The tendency of heating/cooling loads change was depends on external weather condition and optimal temperature for growing crops at each stage. In addition, maximum heating/cooling loads of reference greenhouse were estimated to 644,014 and $756,456kJ{\cdot}hr^{-1}$, respectively.

• 한국대기환경학회지
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• 제20권3호
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• pp.303-315
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• 2004

The change of land use such as the construction of way in mountainous area and tunnel leads to the quantitative change of the greenhouse gas. This study tried to clarify the effect of the change of land use around Miryang Ice Valley on thermal environment of micro-meteorological scale by numerical experiment. We carried out several numerical experiment under different atmospheric conditions with different amount of greenhouse gases. Heating rate increased by the greenhouse gas in the ground level is average of 0.0073 K/day. And the increasing rate if smaller than the daily average heat crossing quantity.

• 농업과학연구
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• 제49권4호
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• pp.737-747
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• 2022

The purpose of this study is to analyze farmers' perceptions of Greenhouse Gas Reduction Projects and identify factors influencing participation in the projects. To achieve the research objective, a survey was conducted and a probit model was adopted for the empirical analysis. The results showed that farmers do not participate in the projects due to a lack of education and promotion and due to economic loss. It also showed that the frequency of training and technical guidance learning, degree of recognition of the need for efforts to reduce greenhouse gases, and the level of recognition of the projects concerned have a positive impact on the willingness to participate in the projects. Meanwhile, participation in agricultural environment conservation programs has a negative impact on it. Enhancement of education and promotion as well as economic support (direct payment, R&D) would be useful to raise the willingness to participate in the projects.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 2017년도 춘계공동학술대회
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• pp.135-135
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• 2017

Greenhouse have been developed to provide the plants with good environmental conditions for cultivation crop, two major factors of which are the inside air temperature and humidity. The inside temperature are influenced by the heating systems, ventilators and for systems among others, which in turn are geverned by some type of controller. Likewise, humidity environment is the result of complex mass exchanges between the inside air and the several elements of the greenhouse and the outside boundaries. Most of the existing models are based on the energy balance method and heat balance equation for modelling the heat and mass fluxes and generating dynamic elements. However, greenhouse are classified as complex system, and need to make a sophisticated modeling. Furthermore, there is a difficulty in using classical control methods for complex process system due to the process are non linear and multi-output(MIMO) systems. In order to predict the time evolution of conditions in certain greenhouse as a function, we present here to use of recurrent neural networks(RNN) which has been used to implement the direct dynamics of the inside temperature and inside humidity of greenhouse. For the training, we used algorithm of a backpropagation Through Time (BPTT). Because the environmental parameters are shared by all time steps in the network, the gradient at each output depends not only on the calculations of the current time step, but also the previous time steps. The training data was emulated to 13 input variables during March 1 to 7, and the model was tested with database file of March 8. The RMSE of results of the temperature modeling was $0.976^{\circ}C$, and the RMSE of humidity simulation was 4.11%, which will be given to prove the performance of RNN in prediction of the greenhouse environment.

• 생물환경조절학회지
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• 제21권1호
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• pp.74-78
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• 2012

본 연구는 전북 부안에서 재배되고 있는 뽕나무를 대상으로 온실 재배를 통하여 조기 수확 및 안정적 수확량 확보가 가능한지를 알아보고자 신초 생육 특성과 이에 관계하는 기상 요인을 분석하였다. 발아 및 착색 시기는 온실의 뽕나무에서 노지에 비해 18~19일 정도 빨랐고, 발아시에서 착색시까지의 일수는 39일로 차이를 나타내지 않았다. 발아 후 39일 동안 온실에서 뽕나무의 신초 길이, 신초당 착과수는 노지와 차이를 나타내지 않았지만, 마디수는 적었다. 생육 기간 동안 온실 내부의 주별 광량은 노지에 비해 0.3~0.8배 범위 수준이었고, 총 누적량은 절반수준으로 아주 적었다. 그러나 온실에서 주별 누적온도는 노지와 거의 차이를 나타내지 않고 후반기로 가며 다소 상승하는 경향이었으며, 총 누적량도 노지에 1.1배로 거의 유사한 수준이었다. 생육 기간 동안 상대습도는 온실에서 53~94.5%로 노지에 비해 대부분 높은 수준을 유지하였다. 따라서 뽕나무는 광의 영향을 적게 받고 안정적인 수량을 조기에 확보할 수 있어 온실 재배 작목으로 적합하다.

• 생물환경조절학회지
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• 제7권4호
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• pp.311-323
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• 1998

현재 경북지방의 수박 및 참외재배에 가장 많이 이용되고 있는 대형터널 하우스의 온도 변화를 분석한 결과, 터널하우스 내 기온은 일몰과 함께 강하하여 외기온과 비슷한 온도를 유지하는 시간은 일몰 후 약 2시간 30분 전후로 나타났으며, 자연환기장치인 환기공 및 수동식 측창이 설치되어 재배기간중 하우스내 최고기온은 4$0^{\circ}C$ 이상 유지되지는 않았다. 하우스야간온도는 높이별 위치에 관계없이 거의 같은 온도로 유지되었으며, 재배기간중 야간온도는 외기온보다 2~3$^{\circ}C$정도 높게 유지할 수 있었지만, 외기온이 적온 이하일 때는 보온의 필요성이 있었다. 또 재배기간중 20cm 깊이의 지온은 2$0^{\circ}C$ 이상을 유지할 수 있어서 적정지온 확보에는 문제가 없었으며, 일변동폭은 3~5$^{\circ}C$ 정도이고 관수로 인한 지온저하는 5~6$^{\circ}C$ 정도였다