• Title/Summary/Keyword: greenhouse test

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A Study on ESG Perception of Real Estate Managers

  • Sangkyu NOH;Jaetae KIM
    • The Journal of Economics, Marketing and Management
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    • v.11 no.6
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    • pp.23-34
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    • 2023
  • Purpose: This study conducted an empirical study to identify the current status of real estate managers' ESG awareness and to derive recommendations for improvement. Research design, data and methodology: A survey was conducted among those who actually manage real estate assets regardless of region. Descriptive statistical analysis, paired sample t-test, and IPA analysis were conducted using SPSS 27.0 statistical package. Results: The results of the t-test showed that respondents perceived their on-site management achievements to be lower than their perceived importance in all areas of ESG. In the IPA matrix, the mean of achievement is higher than 3, which is moderate. Environment (E) was found to be relatively low in importance. In the Social (S) aspect, the achievement level was low compared to its importance, and Governance (G) was found to be low in importance. Conclusions: Based on the analysis, it seems that policies are needed to emphasize the importance of environmental issues such as greenhouse gas reduction in the environment (E) sector and to strengthen realistic achievement in the social (S) and governance (G) sectors.

Study on the performance analysis of long-term field test for protected horticulture heating system using solar thermal energy (태양열 시설원예 난방시스템 장기실증 성능분석 연구)

  • Lee Sang-Nam;Kang Yong-Heack;Yu Chang-Kyun;Kim Jin-Soo
    • New & Renewable Energy
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    • v.1 no.2 s.2
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    • pp.53-59
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    • 2005
  • Objective of the research is to demonstrate solar thermal space and ground heating system which is integrated to a green-house culture facility for reducing healing cost, Increasing the value of product by environment control, and developing advanced culture technology by deploying solar thermal system. Field test for the demonstration was carried out in horticulture complex In Jeju Island. Medium scale solar hot water system was installed in a ground heating culture facility. Reliability and economic aspect of the system which was operated complementary with thermal storage and solar hot water generation were analyzed by investigating collector efficiency, operation performance, and control features. Short term day test on element performance and Long term test of the whole system were carried out. Optimum operating condition and its characteristics were closely Investigated by changing the control condition based on the temperature difference which Is the most important operating parameter For establishing more reliable and optimal design data regarding system scale and operation condition, continuous operation and monitoring on the system need to be further carried out. However, It is expected that, in high-insolation areas where large-scale ground storage is adaptable, solar system demonstrated in the research could be economically competitive and promisingly disseminate over various application areas.

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Uplift Bearing Capacity of Spiral Steel Peg for the Single Span Greenhouse (온실용 나선철항의 인발저항력 검토)

  • Lee, Bong Guk;Yun, Sung Wook;Choi, Man Kwon;Lee, Si Young;Moon, Sung Dong;Yu, Chan;Yoon, Yong Cheol
    • Journal of Bio-Environment Control
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    • v.23 no.2
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    • pp.109-115
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    • 2014
  • This study examined the uplift bearing capacity of spiral steel pegs according to the degree of soil compaction and embedded depth in a small-scaled lab test. As a result, their uplift bearing capacity increased according to the degree of soil compaction and embedded depth. The uplift bearing capacity under the ground condition of 85% compaction rate especially recorded 48.9 kgf, 57.9 kgf, 86.2 kgf and 116.6 kgf at embedded depth of 25 cm, 30 cm, 35 cm and 40 cm, respectively, being considerably higher than under other ground conditions. There were huge differences in the uplift bearing capacity of spiral steel pegs according to the compaction conditions of ground. Their maximum uplift bearing capacity was 116.6 kgf under the ground condition of 85% compaction rate and at embedded depth of 40 cm, and it is very high considering the data of spiral steel pegs. It is thus estimated that wind damage can be effectively reduced by careful maintenance of ground condition surrounding spiral steel pegs. In addition, spiral steel pegs will be able to make a contribution to greenhouse structural stability if proper installation methods are provided including the number and interval according to the types of greenhouse as well as fixation of plastic film. The findings of the study indicate that the optimal effects of spiral steel pegs for greenhouse can be achieved at embedded depth of more than 35cm and compaction degree of more than 85%. The relative density of the model ground in the test was 67% at compaction rate of 85%.

Analysis of Agricultural Working Load Experiments for Reduction Gear Ratio Design of an Electric Tractor Powertrain (전기구동 파워트레인의 감속기어비 설계를 위한 농용 트랙터의 작업 부하 분석)

  • Kim, Jung-Yun;Park, Yeong-Il
    • Transactions of the Korean Society of Automotive Engineers
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    • v.20 no.5
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    • pp.138-144
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    • 2012
  • Recent environmental issues such as exhaust gas and greenhouse effect make the agricultural machinery market takes into account the hybrid and electric propulsion technology used in automotive engineering. Generally the agricultural machinery, particularly an agricultural tractor, needs large load capacity and long continuous operating time comparing with conventional vehicles. In case of a pure electric tractor, it is necessary for considering large capacity batteries and long charging time. Therefore we take an AER extended PHEV (All Electric Range extended Plug-in Hybrid Electric Vehicle) power transmission system in developing an electric tractor in this study. First we propose a PHEV powertrain structure in order to substitute the conventional diesel engine equipped tractor. And we performed the road tests using a conventional mechanical tractor with various load conditions, which were classified and statistically treated real agricultural works. The test results were analysed with respect to the power characteristics of the power source. Finally using the test result, we designed two-stepped reduction gear ratios in the proposed an electric tractor powertrain for carrying out typical agricultural works.

Soil water retention and vegetation survivability improvement using microbial biopolymers in drylands

  • Tran, An Thi Phuong;Chang, Ilhan;Cho, Gye-Chun
    • Geomechanics and Engineering
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    • v.17 no.5
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    • pp.475-483
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    • 2019
  • Vegetation cover plays a vital role in stabilizing the soil structure, thereby contributing to surface erosion control. Surface vegetation acts as a shelterbelt that controls the flow velocity and reduces the kinetic energy of the water near the soil surface, whereas vegetation roots reinforce the soil via the formation of root-particle interactions that reduce particle detachment. In this study, two vegetation-testing trials were conducted. The first trial was held on cool-season turfgrasses seeded in a biopolymer-treated site soil in an open greenhouse. At the end of the test, the most suitable grass type was suggested for the second vegetation test, which was conducted in an environmental control chamber. In the second test, biopolymers, namely, starch and xanthan gum hydrogels (pure starch, pure xanthan gum, and xanthan gum-starch mixtures), were tested as soil conditioners for improving the water-holding capacity and vegetation growth in sandy soils. The results support the possibility that biopolymer treatments may enhance the survival rate of vegetation under severe drought environments, which could be applicable for soil stabilization in arid and semiarid regions.

Characteristics of Uplift Resistance According to Shape Factor and Contact Area of Wooden Piles (나무말뚝 형상과 접촉면적에 따른 인발저항력 특성)

  • Song, Chang Seob;Kim, Myeong Hwan;Park, Oh Hyun;Woo, Jea Kuen;Kim, Gi Beom
    • Journal of The Korean Society of Agricultural Engineers
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    • v.63 no.3
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    • pp.27-33
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    • 2021
  • Reclaimed land was mainly used as agricultural land for rice production. As a higher value-added business in the agriculture has recently been activated, green houses are being constructed. In case of green house construction on the reclaimed land, it is generally soft ground with high soil water content, so it is important to design the foundation for greenhouse construction. The object of this study, a pull-out test was conducted to derive the base line data of the wooden pile foundation when constructing a green house. To reproduce the actual site, 30% of soil saturation and 70% of soil saturation were created in the soil box. Groove number and depth were set as design factors of the wooden pile, and a pull-out test was conducted. As a result of the test, pull resistance increased as the number of grooves increased, pull-out resistance according to groove depth was different according to soil saturation. Also, after the experiment, we want to compare the set-up effects over time.

Improvement of Heat Pump Heating Performance by Selective Heat Storage Using Air Heat of Inside and Outside Greenhouse (온실 내외부 공기열의 선택적 축열에 의한 히트펌프 난방성능 개선)

  • Kwon, Jin Kyung;Kim, Seung Hee;Jeon, Jong Gil;Kang, Youn Koo;Jang, Kab Yeol
    • Journal of Bio-Environment Control
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    • v.26 no.4
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    • pp.353-360
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    • 2017
  • In this study, the design and performance test of the air to water heat pump capable of producing hot water for greenhouse heating by using the surplus solar heat inside the greenhouse and the air heat outside greenhouse as the selective heat source were conducted. The heat storage operations using the surplus solar heat and the outside air heat were designed to be switched according to the setting temperature of the greenhouse in consideration of the optimum temperature range of the crop. In the developed system, it was possible to automatically control the switching of heat storage operation, heating and ventilation by setting 12 reference temperatures on the control panel. In the selective heat storage operation with the surplus solar heat and outside air heat, the temperature of thermal storage tank was controlled variably from $35^{\circ}C$ to $52^{\circ}C$ according to the heat storage rate and heating load. The heat storage operation times using the surplus solar heat and outside air heat were 23.1% and 30.7% of the experimental time respectively and the heat pump pause time was 46.2%. COP(coefficient of performance) of the heat pump of the heat storage operation using the surplus solar heat and outside air heat were 3.83 and 2.77 respectively and was 3.24 for whole selective heat storage operation. For the comparative experiment, the heat storage operation using the outside air heat only was performed under the condition that the temperature of the thermal storage tank was controlled constantly from 50 to $52^{\circ}C$, and COP was analyzed to be 2.33. As a result, it was confirmed that the COP of the heat storage operation using the surplus solar heat and outside air heat as selective heat source and the variable temperature control of the thermal storage tank was 39% higher than that of the general heat storage operation using the outside air heat only and the constant temperature control of the thermal storage tank.

Process Improvement and Evaluation of 0.1 MW-scale Test Bed using Amine Solvent for Post-combustion CO2 Capture (0.1 MW급 연소후 습식아민 CO2 포집 Test Bed 공정개선효과 검증)

  • Park, Jong Min;Cho, Seong Pill;Lim, Ta Young;Lee, Young ill
    • KEPCO Journal on Electric Power and Energy
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    • v.2 no.1
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    • pp.103-108
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    • 2016
  • Carbon Capture and Storage technologies are recognized as key solution to meet greenhouse gas emission standards to avoid climate change. Although MEA (monoethanolamine) is an effective amine solvent in $CO_2$ capture process, the application is limited by high energy consumption, i.e., reduction of 10% of efficiency of coal-fired power plants. Therefore the development of new solvent and improvement of $CO_2$ capture process are positively necessary. In this study, improvement of $CO_2$ capture process was investigated and applied to Test Bed for reducing energy consumption. Previously reported technologies were examined and prospective methods were determined by simulation. Among the prospective methods, four applicable methods were selected for applying to 0.1 MW Test Bed, such as change of packing material in absorption column, installing the Intercooling System to absorption column, installing Rich Amine Heater and remodeling of Amines Heat Exchanger. After the improvement construction of 0.1 MW Test Bed, the effects of each suggested method were evaluated by experimental results.

Analysis for Aerodynamic Resistance of Chrysanthemum Canopy through Wind Tunnel Test (풍동실험을 통한 국화군락의 공기유동 저항 분석)

  • Yu, In-Ho;Yun, Nam-Kyu;Cho, Myeong-Whan;Lee, In-Bok
    • Journal of Bio-Environment Control
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    • v.17 no.2
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    • pp.83-89
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    • 2008
  • A wind tunnel test was conducted at Protected Horticulture Experiment Station of National Horticultural Research Institute in Busan to find the aerodynamic resistance and quadratic resistance coefficient of chrysanthemum in greenhouse. The internal plants of the CFD model has been designed as a porous media because of the complexity of its physical shapes. Then the aerodynamic resistance value should be input for analyzing CFD model that crop is considered while the value varies by crops. In this study, the aerodynamic resistance value of chrysanthemum canopy was preliminarily found through wind tunnel test. The static pressure at windward increased as wind velocity and planting density increased. The static pressure at leeward decreased as wind velocity increased but was not significantly affected by planting density. The difference of static pressure between windward and leeward increased as wind velocity and planting density increased. The aerodynamic resistance value of chrysanthemum canopy was found to be 0.22 which will be used later as the input data of Fluent CFD model. When the planting distances were $9{\times}9\;cm$, $11{\times}11\;cm$, and $13{\times}13\;cm$, the quadratic resistance coefficients of porous media were found to be 2.22, 1.81, and 1.07, respectively. These values will be used later as the input data of CFX CFD model.

Controlling effect of several surfactants on barley powdery mildew caused by Erysiphae graminis (보리 흰가루병에 대한 몇 가지 계면활성제의 방제 효과)

  • Jang, Kyung-Soo;Yoo, Joo-Hyeon;Choi, Gyung-Ja;Kim, Jin-Cheol;Cho, Kwang-Yun;Kim, Heung-Tae
    • The Korean Journal of Pesticide Science
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    • v.5 no.2
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    • pp.51-57
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    • 2001
  • Controlling effect of several surfactants on barley powdery mildew (pathogen : Erysiphae graminis) and those influence on fungicidal activity by tank-mixing with commercialized fungicides were investigated in greenhouse test with barley seedlings. While protective activity of PNPP showed 90% at $1,000{\mu}g/mL$, that of LN 13.0 91.2%, tile best among 8 surfactants used in curative test. With $500{\mu}g/mL$, LN 13.0 showed 4% of disease percentage on the first leaf of narley continuously 4 days after the curative application. Excent for PNPP, the other surfactants, including NP 13.0, LN 13.0, and PAS, showed good inhibitory activity against spore germination in water agar medium amended with those surfactants. PAS, which showed very poor effect against barley powdery mildew in greenhouse test, strongly inhibited spore germination. Fungicide of triadimefon and triforine showed no controlling activity against Erysiphae graminis in narley seedlings, but they highly controlled powdery mildew in case of addition with $500{\mu}g/mL$ of LN 13.0 and Tween 20. SP 13.0, NP 13.0, LN 13.0 and DBC showed severe phytotoxicity in first leaf of barley seedlings, but Tween 20, SLIS, PAS, and PNPP not at $1,000{\mu}g/mL$.

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