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In-Beum Lee
Laboratory of Aero-Environmental Engineering, Department of Rural System Engineering College of Agriculture and Life Science, Seoul National University, Seoul 08826, Korea

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Journal article
Published: 26 July 2021 in Sustainability
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This work aims at using the Computational Fluid Dynamic (CFD) approach to study the distributed microclimate in the leaf boundary layer of greenhouse crops. Understanding the interactions in this microclimate of this natural habitat of plant pests (i.e., boundary layer of leaves), is a prerequisite for their control through targeted climate management for sustainable greenhouse production. The temperature and humidity simulations, inside the greenhouse, were performed using CFD code which has been adapted to simulate the plant activity within each mesh in the crop canopy. The air temperature and air humidity profiles within the boundary layer of leaves were deduced from the local surrounding climate parameters, based on an analytical approach, encapsulated in a Used Defined Function (UDF), and dynamically linked to the CFD solver, a work that forms an innovative and original task. Thus, this model represents a new approach to investigate the microclimate in the boundary layer of leaves under greenhouses, which resolves the issue of the inaccessibility of this area by the conventionnel measurement tools. The findings clearly showed that (i) contrarily to what might be expected, the microclimate parameters within the boundary layer of leaves are different from the surrounding climate in the greenhouse. This is particularly visible during photoperiods when the plant’s transpiration activity is at its maximum and that (ii) the climatic parameters in the leaf boundary layer are more coupled with leaf surfaces than with those of greenhouse air. These results can help developing localized intervention strategies on the microclimate within boundary layer of plant leaves, leading to improved and sustainable pest control management. The developed climatic strategies will make it possible to optimize resources use efficiency.

ACS Style

Hicham Fatnassi; Thierry Boulard; Christine Poncet; Nikolaos Katsoulas; Thomas Bartzanas; Murat Kacira; Habtamu Giday; In-Bok Lee. Computational Fluid Dynamics Modelling of the Microclimate within the Boundary Layer of Leaves Leading to Improved Pest Control Management and Low-Input Greenhouse. Sustainability 2021, 13, 8310 .

AMA Style

Hicham Fatnassi, Thierry Boulard, Christine Poncet, Nikolaos Katsoulas, Thomas Bartzanas, Murat Kacira, Habtamu Giday, In-Bok Lee. Computational Fluid Dynamics Modelling of the Microclimate within the Boundary Layer of Leaves Leading to Improved Pest Control Management and Low-Input Greenhouse. Sustainability. 2021; 13 (15):8310.

Chicago/Turabian Style

Hicham Fatnassi; Thierry Boulard; Christine Poncet; Nikolaos Katsoulas; Thomas Bartzanas; Murat Kacira; Habtamu Giday; In-Bok Lee. 2021. "Computational Fluid Dynamics Modelling of the Microclimate within the Boundary Layer of Leaves Leading to Improved Pest Control Management and Low-Input Greenhouse." Sustainability 13, no. 15: 8310.

Journal article
Published: 22 July 2021 in Agronomy
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To utilize the energy in the thermal effluent, many attempts have been made to use the thermal effluent for agricultural facilities such as greenhouses. As the first step, it is important to estimate the energy loads of the greenhouse for deciding a suitable scale for the heating and cooling. Then, it is available to estimate the energy efficiency of the thermal effluent heat pump system installed in the greenhouse. Therefore, the main objectives of this study were to design and validate an energy model of the experimental greenhouse growing Irwin mangoes and to estimate the annual and maximum energy loads using building energy simulation (BES). Field experiments were conducted in a multi-span plastic-covered greenhouse growing Irwin mangoes to measure the internal environments of the greenhouse and crop characteristics. The energy exchange model of the greenhouse considering crop, cladding, heat pump was developed using BES. The BES model was validated using the data measured at field experiments. The designed model was found to be able to provide satisfactory estimates of the changes of the internal air temperature of the greenhouse (R2 = 0.94 and d = 0.97). The hourly energy loads computed by using the validated model were used to analyse the periodic and maximum energy loads according to the growth stage of the cultivated crops. Finally, the energy costs were compared according to the type of energy source based on the calculated annual energy loads. The average energy cost when using the thermal effluent—heat pump system was found to be 68.21% lower than that when a kerosene boiler was used.

ACS Style

Sang-Yeon Lee; In-Bok Lee; Seung-No Lee; Uk-Hyeon Yeo; Jun-Gyu Kim; Rack-Woo Kim; Cristina Decano-Valentin. Dynamic Energy Exchange Modelling for a Plastic-Covered Multi-Span Greenhouse Utilizing a Thermal Effluent from Power Plant. Agronomy 2021, 11, 1461 .

AMA Style

Sang-Yeon Lee, In-Bok Lee, Seung-No Lee, Uk-Hyeon Yeo, Jun-Gyu Kim, Rack-Woo Kim, Cristina Decano-Valentin. Dynamic Energy Exchange Modelling for a Plastic-Covered Multi-Span Greenhouse Utilizing a Thermal Effluent from Power Plant. Agronomy. 2021; 11 (8):1461.

Chicago/Turabian Style

Sang-Yeon Lee; In-Bok Lee; Seung-No Lee; Uk-Hyeon Yeo; Jun-Gyu Kim; Rack-Woo Kim; Cristina Decano-Valentin. 2021. "Dynamic Energy Exchange Modelling for a Plastic-Covered Multi-Span Greenhouse Utilizing a Thermal Effluent from Power Plant." Agronomy 11, no. 8: 1461.

Journal article
Published: 17 June 2021 in Agronomy
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A substantial reduction in the environmental impacts related to the construction and operation of agricultural buildings is needed to adapt to the continuing development of agriculture. The life cycle assessment (LCA) is a methodology used to quantify the environmental impact of different processes involved in the production and therefore has been increasingly applied to assess the environmental burden. However, most LCA-related research studies have focused on the overall environmental impact of the entire system without considering the energy load of the agricultural buildings. By integrating the LCA tool with other design tools such as the building energy simulation (BES), the identification of environmental hotspots and the mitigation options become possible during the design process. Thus, the objective of the paper was to identify the current integration approaches used to combine BES and LCA results to assess the environmental impact of different heating systems such as absorption heat pump (AHP) using energy from thermal effluent, electricity-powered heat pump and kerosene-powered boilers used in a conventional multi-span Korean greenhouse. The assessment result revealed that the environmental impact caused using a kerosene-powered boiler is largest in terms of the acidification potential (AP), global warming potential (GWP) and Eutrophication Potential (EP) of 1.15 × 100 kg SO2-eq, 1.13 × 102 kg CO2-eq and 1.62 × 10−1 kg PO4-eq, respectively. Detailed analysis of the result showed that the main contributor for greenhouse gas emission was caused by the type, amount and source of energy used to heat the greenhouse, which contributed to a maximum of 86.59% for case 1, 96.69% for case 2 and a maximum of 96.47% for case 3, depending on the type of greenhouse gas being considered.

ACS Style

Cristina Decano-Valentin; In-Bok Lee; Uk-Hyeon Yeo; Sang-Yeon Lee; Jun-Gyu Kim; Se-Jun Park; Young-Bae Choi; Jeong-Hwa Cho; Hyo-Hyeog Jeong. Integrated Building Energy Simulation–Life Cycle Assessment (BES–LCA) Approach for Environmental Assessment of Agricultural Building: A Review and Application to Greenhouse Heating Systems. Agronomy 2021, 11, 1230 .

AMA Style

Cristina Decano-Valentin, In-Bok Lee, Uk-Hyeon Yeo, Sang-Yeon Lee, Jun-Gyu Kim, Se-Jun Park, Young-Bae Choi, Jeong-Hwa Cho, Hyo-Hyeog Jeong. Integrated Building Energy Simulation–Life Cycle Assessment (BES–LCA) Approach for Environmental Assessment of Agricultural Building: A Review and Application to Greenhouse Heating Systems. Agronomy. 2021; 11 (6):1230.

Chicago/Turabian Style

Cristina Decano-Valentin; In-Bok Lee; Uk-Hyeon Yeo; Sang-Yeon Lee; Jun-Gyu Kim; Se-Jun Park; Young-Bae Choi; Jeong-Hwa Cho; Hyo-Hyeog Jeong. 2021. "Integrated Building Energy Simulation–Life Cycle Assessment (BES–LCA) Approach for Environmental Assessment of Agricultural Building: A Review and Application to Greenhouse Heating Systems." Agronomy 11, no. 6: 1230.

Journal article
Published: 03 April 2021 in Biosystems Engineering
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This study attempted to develop a virtual reality (VR) simulator to educate greenhouse farmers and consultants. In this first of two papers, computational fluid dynamics (CFD) simulation was used to analyse the aerodynamic environment inside the greenhouse for growing the tomato crop. Representative aerodynamic problems that can occur in winter and summer seasons inside greenhouses in Korea were derived through a field survey and literature review. The cases examined for CFD simulation were based on a high-rise three-span 1–2 W type greenhouse. Moreover, the CFD model was validated using the measured air temperature and wind speed in actual greenhouses. Then, the analysis of the aerodynamic environment inside a 1–2 W type greenhouse for growing the tomato crop was performed according to various environmental conditions using the validated CFD model. During the winter, the CFD-computed results revealed that the installation of a thermal curtain was essential to prevent heat loss. Heating efficiency was analysed when a duct was connected to the outlet of the heater. From the simulations, air temperature could be properly maintained when the interval between duct perforations was less than a ratio of 1.1 with a perforation angle of 45°. In the summer, both side and roof vents should be fully opened to maintain the maximum ventilation rate. Furthermore, the installation of a shading screen to prevent the increase of air temperature due to high solar radiation is recommended.

ACS Style

Rack-Woo Kim; Jun-Gyu Kim; In-Bok Lee; Uk-Hyeon Yeo; Sang-Yeon Lee; Cristina Decano-Valentin. Development of three-dimensional visualisation technology of the aerodynamic environment in a greenhouse using CFD and VR technology, part 1: Development of VR a database using CFD. Biosystems Engineering 2021, 207, 33 -58.

AMA Style

Rack-Woo Kim, Jun-Gyu Kim, In-Bok Lee, Uk-Hyeon Yeo, Sang-Yeon Lee, Cristina Decano-Valentin. Development of three-dimensional visualisation technology of the aerodynamic environment in a greenhouse using CFD and VR technology, part 1: Development of VR a database using CFD. Biosystems Engineering. 2021; 207 ():33-58.

Chicago/Turabian Style

Rack-Woo Kim; Jun-Gyu Kim; In-Bok Lee; Uk-Hyeon Yeo; Sang-Yeon Lee; Cristina Decano-Valentin. 2021. "Development of three-dimensional visualisation technology of the aerodynamic environment in a greenhouse using CFD and VR technology, part 1: Development of VR a database using CFD." Biosystems Engineering 207, no. : 33-58.

Journal article
Published: 02 April 2021 in Biosystems Engineering
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The aim was to develop a virtual reality (VR) simulator to help educate greenhouse farmers and consultants. In this second paper a VR simulator that visualises the aerodynamic environment inside greenhouses was developed using VR technology. The three-dimensional greenhouse simulated was designed following the computational fluid dynamics (CFD) computed cases of Kim et al. (reference required). Specifically, the three-dimensional tomato crop models used were created using a three-dimensional scanner. The virtual space was constructed based on the real image models of the greenhouses and the tomato crops. To visualise the aerodynamic environment in the virtual space, a C language-based code was developed to extract the CFD-computed results. Visualisation of the aerodynamic environment was performed using contour plots, two-dimensional vector flows, and three-dimensional vector flows. Contour plots visualised the air temperature and relative humidity through the colours on the active plane. Two-dimensional vector flows represented two-dimensional flows on the active plane. From streamline data, three-dimensional vector flows were developed to represent the overall airflow of the greenhouse. A tablet-shaped user interface (UI) was created so that the user can directly select the desired cases to display. A set of surveys were conducted using random users to optimise the developed VR simulator. From the results of surveys, the final VR simulator to educate the aerodynamic environment in the greenhouse was developed. It is intended to disseminate the VR simulator to various organisations such as educational institutions, research centres, and consulting companies.

ACS Style

Rack-Woo Kim; Jun-Gyu Kim; In-Bok Lee; Uk-Hyeon Yeo; Sang-Yeon Lee; Cristina Decano-Valentin. Development of three-dimensional visualisation technology of the aerodynamic environment in a greenhouse using CFD and VR technology, Part 2: Development of an educational VR simulator. Biosystems Engineering 2021, 207, 12 -32.

AMA Style

Rack-Woo Kim, Jun-Gyu Kim, In-Bok Lee, Uk-Hyeon Yeo, Sang-Yeon Lee, Cristina Decano-Valentin. Development of three-dimensional visualisation technology of the aerodynamic environment in a greenhouse using CFD and VR technology, Part 2: Development of an educational VR simulator. Biosystems Engineering. 2021; 207 ():12-32.

Chicago/Turabian Style

Rack-Woo Kim; Jun-Gyu Kim; In-Bok Lee; Uk-Hyeon Yeo; Sang-Yeon Lee; Cristina Decano-Valentin. 2021. "Development of three-dimensional visualisation technology of the aerodynamic environment in a greenhouse using CFD and VR technology, Part 2: Development of an educational VR simulator." Biosystems Engineering 207, no. : 12-32.

Journal article
Published: 20 November 2020 in Agronomy
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With the rise in livestock production, the odour concentration emitted from livestock facilities has significantly increased. For this reason, odour complaints have become a major issue. The dispersion of the odour into the atmosphere is affected by various factors (wind speed, wind direction, atmospheric stability, terrain condition, ventilation type, and so on). Thus, a thorough analysis on the factor influencing odour dispersion is necessary to establish regulations and policies for odour management. Therefore, this research aimed to evaluate odour dispersion generated from a pig house with complex terrain using computational fluid dynamics (CFD) and to statistically determine the key factor for odour dispersion. By comparing CFD-computed results with field-measured data, an appropriate grid size, time step, and turbulence model of the CFD model were determined. Considering various factors, case studies were performed using the validated CFD model. The CFD-computed results showed that odour dispersion distance at the level of 1 OU m−3 ranged from 129.7 to 1488.1 m. The prediction of odour dispersion distance varies with the change of factor being analysed. Finally, the statistical analysis showed that the most influential factor that affected odour dispersion distance was the wind speed with a t-value: −9.057.

ACS Style

Uk-Hyeon Yeo; Cristina Decano-Valentin; Taehwan Ha; In-Bok Lee; Rack-Woo Kim; Sang-Yeon Lee; Jun-Gyu Kim. Impact Analysis of Environmental Conditions on Odour Dispersion Emitted from Pig House with Complex Terrain Using CFD. Agronomy 2020, 10, 1828 .

AMA Style

Uk-Hyeon Yeo, Cristina Decano-Valentin, Taehwan Ha, In-Bok Lee, Rack-Woo Kim, Sang-Yeon Lee, Jun-Gyu Kim. Impact Analysis of Environmental Conditions on Odour Dispersion Emitted from Pig House with Complex Terrain Using CFD. Agronomy. 2020; 10 (11):1828.

Chicago/Turabian Style

Uk-Hyeon Yeo; Cristina Decano-Valentin; Taehwan Ha; In-Bok Lee; Rack-Woo Kim; Sang-Yeon Lee; Jun-Gyu Kim. 2020. "Impact Analysis of Environmental Conditions on Odour Dispersion Emitted from Pig House with Complex Terrain Using CFD." Agronomy 10, no. 11: 1828.

Journal article
Published: 20 November 2020 in Biosystems Engineering
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Thermal and hygroscopic environments inside a duck house are two of the most important factors directly related to their productivity and energy costs. However, few quantitative analyses of these environments have been performed. The objective of this study was to develop a dynamic energy model for the combined and real-time quantitative analysis of thermal and hygroscopic environments inside a mechanically ventilated duck house. To identify seasonal problems and develop the energy model, the internal and external environments of the duck house were first monitored via field experiments. Additionally, chamber experiments were conducted in a temperature- and humidity-controlled chamber to calculate the amount of evaporation from duck-house litter for incorporation of these data into the energy model. According to the environmental data measured in the field experiments and the results of the chamber experiments, the dynamic energy model of the duck house was developed using building energy simulation (BES). The BES model was validated by comparison of the BES-computed and field-measured data of the air temperature and relative humidity. The results showed errors of 1.71% and 4.33% for the air temperature and relative humidity, respectively. Finally, the validated BES model of the duck house was used to analyse the seasonal periodic and maximum energy loads. Furthermore, the high-temperature stress of the ducks in summer was also estimated for different space allowances.

ACS Style

Sang-Yeon Lee; In-Bok Lee; Rack-Woo Kim; Uk-Hyeon Yeo; Jun-Gyu Kim; Kyeong-Seok Kwon. Dynamic energy modelling for analysis of the thermal and hygroscopic environment in a mechanically ventilated duck house. Biosystems Engineering 2020, 200, 431 -449.

AMA Style

Sang-Yeon Lee, In-Bok Lee, Rack-Woo Kim, Uk-Hyeon Yeo, Jun-Gyu Kim, Kyeong-Seok Kwon. Dynamic energy modelling for analysis of the thermal and hygroscopic environment in a mechanically ventilated duck house. Biosystems Engineering. 2020; 200 ():431-449.

Chicago/Turabian Style

Sang-Yeon Lee; In-Bok Lee; Rack-Woo Kim; Uk-Hyeon Yeo; Jun-Gyu Kim; Kyeong-Seok Kwon. 2020. "Dynamic energy modelling for analysis of the thermal and hygroscopic environment in a mechanically ventilated duck house." Biosystems Engineering 200, no. : 431-449.

Journal article
Published: 28 August 2020 in Energy Conversion and Management
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Utilization of industrial off-gases to produce valuable chemicals has the advantages of reducing dependence on fossil fuels. Despite many studies of off-gas utilization, production of secondary chemicals including detailed kinetic models integrated with a power-generation system to fully utilize byproducts has not been considered. The goal of this study was to techno-economically evaluate a polygeneration system to produce olefins and power from steel-mill off-gases. Two process cases were evaluated; they use carbon monoxide-rich Linz-Donawitz converter gas with either hydrogen or coke oven gas as feed. The hydrogen was concentrated from coke oven gas by using membrane-separation technology. These gases reacted with Linz-Donawitz converter gas to yield methanol, which was then converted to olefins. Kinetic models were applied for methanol synthesis and methanol-to-olefin reaction. Heat exchanger networks are designed to minimize utility usage, and a power generation system that uses the Rankine cycle to fully utilize byproduct stream. Calculated minimum selling prices of ethylene by discounted cash flow analysis were US$ 2030∙tonne−1 when hydrogen was the feed gas, and US$ 1064∙tonne−1 when coke oven gas was the feed gas; both were higher than the current minimum selling price (~US$ 720∙tonne−1) of ethylene derived from naphtha. The reduction in minimum selling price by use of coke oven gas is due to the revenue of power generation from coke oven gas retentate. Linz-Donawitz converter gas production with hydrogen is the most sensitive to feed price, whereas Linz-Donawitz converter gas-with- coke oven gas is the most sensitive to capital investment. The analysis demonstrates that neither system is economically viable under the current condition. The findings of this study represent a basic analysis for future improvements of the off-gas to olefins process, especially highly integrated system with power generation.

ACS Style

Jeong-Keun Lee; Sunkyu Shin; Geun-Jae Kwak; Min-Kyung Lee; In-Beum Lee; Young-Seek Yoon. Techno-economic evaluation of polygeneration system for olefins and power by using steel-mill off-gases. Energy Conversion and Management 2020, 224, 113316 .

AMA Style

Jeong-Keun Lee, Sunkyu Shin, Geun-Jae Kwak, Min-Kyung Lee, In-Beum Lee, Young-Seek Yoon. Techno-economic evaluation of polygeneration system for olefins and power by using steel-mill off-gases. Energy Conversion and Management. 2020; 224 ():113316.

Chicago/Turabian Style

Jeong-Keun Lee; Sunkyu Shin; Geun-Jae Kwak; Min-Kyung Lee; In-Beum Lee; Young-Seek Yoon. 2020. "Techno-economic evaluation of polygeneration system for olefins and power by using steel-mill off-gases." Energy Conversion and Management 224, no. : 113316.

Journal article
Published: 05 April 2020 in Energy
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Coke-oven gas and Linz Donawitz gas are pollutive by-product gases generated from steel plants. The gases are currently combusted or released to atmosphere, but those can be economically utilized as chemical product. Thus, this study proposes improved methanol production process from the gases, by considering two different strategies: efficiency (Case 1) and productivity (Case 2). Both processes are rigorously integrated using Aspen Plus V10 and evaluated from the perspectives of productivity, thermodynamic efficiency, environmental impact, and techno-economics. Compared to Case 1, Case 2 had 2.1 times the productivity but required 3 times natural gas. As a result, Case 1 showed better efficiencies of 58–68% (46–56% in Case 2), reduced larger carbon emission of 425 kmol/h (123 kmol/h in Case 2), and had lower minimum selling price of 371 $/tonne (398 $/tonne in Case 2). Two proposed processes are also economically superior than similar previous processes (550–712 $/tonne). This study confirms that both presented novel processes are sustainable and economically viable, and also improves the understanding of methanol production from the waste gases of steel production.

ACS Style

Sunkyu Shin; Jeong-Keun Lee; In-Beum Lee. Development and techno-economic study of methanol production from coke-oven gas blended with Linz Donawitz gas. Energy 2020, 200, 117506 .

AMA Style

Sunkyu Shin, Jeong-Keun Lee, In-Beum Lee. Development and techno-economic study of methanol production from coke-oven gas blended with Linz Donawitz gas. Energy. 2020; 200 ():117506.

Chicago/Turabian Style

Sunkyu Shin; Jeong-Keun Lee; In-Beum Lee. 2020. "Development and techno-economic study of methanol production from coke-oven gas blended with Linz Donawitz gas." Energy 200, no. : 117506.

Journal article
Published: 05 March 2020 in IEEE Transactions on Industrial Informatics
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In this paper, we propose a framework to monitor the chatter phenomenon and to diagnose the cause variables of chatter occurred in hot strip mill process (HSMP). For monitoring chatter, we develop a chatter index (CI) that quantifies chatter to confirm its occurrence. Based on data classified as normal by the CI, a multivariate statistical process monitoring model for detecting chatter is constructed using the modified independent component analysis (MICA) method. The monitoring results show that the model based on MICA outperforms other models based on principal component analysis and independent component analysis. For diagnosis of the cause variables of detected chatter, various contribution plots can be used. In this paper, we develop a relative contribution plot for a more obvious diagnosis than the existing contribution plot. Using this, we diagnose and analyze the cause variables of the detected chatter in the HSMP.

ACS Style

Ha-Nui Jo; Byeong Eon Park; Yumi Ji; Dong-Kuk Kim; Jeong Eun Yang; In-Beum Lee. Chatter Detection and Diagnosis in Hot Strip Mill Process With a Frequency-Based Chatter Index and Modified Independent Component Analysis. IEEE Transactions on Industrial Informatics 2020, 16, 7812 -7820.

AMA Style

Ha-Nui Jo, Byeong Eon Park, Yumi Ji, Dong-Kuk Kim, Jeong Eun Yang, In-Beum Lee. Chatter Detection and Diagnosis in Hot Strip Mill Process With a Frequency-Based Chatter Index and Modified Independent Component Analysis. IEEE Transactions on Industrial Informatics. 2020; 16 (12):7812-7820.

Chicago/Turabian Style

Ha-Nui Jo; Byeong Eon Park; Yumi Ji; Dong-Kuk Kim; Jeong Eun Yang; In-Beum Lee. 2020. "Chatter Detection and Diagnosis in Hot Strip Mill Process With a Frequency-Based Chatter Index and Modified Independent Component Analysis." IEEE Transactions on Industrial Informatics 16, no. 12: 7812-7820.

Journal article
Published: 08 January 2020 in Korean Journal of Chemical Engineering
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Low-Density Polyethylene (LDPE) was synthesized from ethylene at high-temperature and pressure condition. Hyper-compressor used to increase pressure up to 3,500 atm should be monitored and controlled delicately or it cannot guarantee stable operation of the process causing process shutdown (SD), which is directly related to product yield and process safety. This paper presents a data-based multivariate statistical monitoring method to detect anomalies in the hyper-compressor of a LDPE manufacturing process with weighted principal component analysis model (WPCA), which can consider both time-varying and time-invariant characteristic of data combining principal component analysis (PCA) and slow feature analysis (SFA). Operation data of the LDPE manufacturing process was gathered hourly for four years. WPCA-based principal component control limit (PCCL) was used as an index to determine anomaly and applied to five emergency shutdown (ESD) cases, respectively. As a result, all the five anomalies were detected by a PCCL, respectively, as a sign of SD. Moreover, it shows a better anomaly detection performance than the monitoring method using T2 and squared prediction error (SPE) based on PCA, SFA, or WPCA.

ACS Style

Byeong Eon Park; Ji Seon Kim; Jeong-Keun Lee; In-Beum Lee. Anomaly detection in a hyper-compressor in low-density polyethylene manufacturing processes using WPCA-based principal component control limit. Korean Journal of Chemical Engineering 2020, 37, 11 -18.

AMA Style

Byeong Eon Park, Ji Seon Kim, Jeong-Keun Lee, In-Beum Lee. Anomaly detection in a hyper-compressor in low-density polyethylene manufacturing processes using WPCA-based principal component control limit. Korean Journal of Chemical Engineering. 2020; 37 (1):11-18.

Chicago/Turabian Style

Byeong Eon Park; Ji Seon Kim; Jeong-Keun Lee; In-Beum Lee. 2020. "Anomaly detection in a hyper-compressor in low-density polyethylene manufacturing processes using WPCA-based principal component control limit." Korean Journal of Chemical Engineering 37, no. 1: 11-18.

Journal article
Published: 14 November 2019 in Biosystems Engineering
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In terms of maintaining an optimum micro-climates in livestock facilities, many problems exist. In particular, many consultants, as well as farmers, have misunderstand the process and often made wrong judgements on ventilation. Airflow is the main mechanism of internal environmental distribution. However, airflow is invisible and difficult to predict and measure. Computational fluid dynamics (CFD) simulations have been used to analyse the aerodynamics of livestock building micro-climates. CFD-computed results can be used to educate farmers and consultants. However, they can be of limited use when providing education via a two-dimensional screen. This could be improved by visualising the computed results in a three-dimensional space rather than on a two-dimensional surface. This could be accomplished using virtual reality (VR). In this study, CFD-computed results were combined with VR technology to develop an educational simulator. Firstly, an extensive review was carried out of research papers, reports, journals, and publications on the livestock industry, to find seasonally representative problems that occurred at piglet rearing houses in Korea. Then, a CFD simulation model was designed for computing the micro-climate of a piglet house according to its external climate and ventilation type. These CFD models were designed based on a 2009 Korean standard for piglet houses using validation results of a previous study (Kim et al., 2017). The CFD-computed results, such as internal airflow, air temperature, humidity, and gas, were then applied to a VR simulator for educating farmers and consultants. Finally, a user interface was developed to maximise accessibility and usability for VR users.

ACS Style

Rack-Woo Kim; Jun-Gyu Kim; In-Bok Lee; Uk-Hyeon Yeo; Sang-Yeon Lee. Development of a VR simulator for educating CFD-computed internal environment of piglet house. Biosystems Engineering 2019, 188, 243 -264.

AMA Style

Rack-Woo Kim, Jun-Gyu Kim, In-Bok Lee, Uk-Hyeon Yeo, Sang-Yeon Lee. Development of a VR simulator for educating CFD-computed internal environment of piglet house. Biosystems Engineering. 2019; 188 ():243-264.

Chicago/Turabian Style

Rack-Woo Kim; Jun-Gyu Kim; In-Bok Lee; Uk-Hyeon Yeo; Sang-Yeon Lee. 2019. "Development of a VR simulator for educating CFD-computed internal environment of piglet house." Biosystems Engineering 188, no. : 243-264.

Journal article
Published: 04 November 2019 in Biosystems Engineering
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In large greenhouses with information and communication technology capability, environmental conditions can be measured and communicated to control the internal environment. However, in such greenhouses, it is difficult to control the internal environment uniformly and appropriately. Additionally, there is uncertainty regarding whether the data measured at a particular location accurately represents the entire greenhouse environment. Furthermore, the locations of sensors are usually determined based on the experience of growers and the greenhouse designers. To accurately measure the internal environment of a greenhouse, it is necessary to properly select the installation locations of the sensors. The objective of this study was to determine the optimal sensor placement for monitoring and controlling the internal environment of a greenhouse. The study greenhouse was an eight-span plastic greenhouse growing Irwin mango crops. Air temperature data measured at nine locations in the greenhouse were used. All of the possible combinations of monitoring locations were evaluated, and optimal sensor placements were selected according to the number of sensors. The optimisation was conducted using two methods: error-based sensor placement and entropy-based sensor placement. Using the former approach, sensor locations for which the monitored data were close to the reference value, i.e. the average data of all the measurement locations, were selected. Using the latter approach, sensor locations influenced by the external weather conditions resulting in poor environmental control were selected. Using these methods, optimal sensor locations for representing the entire environment of the facility and for detecting areas with significant air temperature variations were determined.

ACS Style

Sang-Yeon Lee; In-Bok Lee; Uk-Hyeon Yeo; Rack-Woo Kim; Jun-Gyu Kim. Optimal sensor placement for monitoring and controlling greenhouse internal environments. Biosystems Engineering 2019, 188, 190 -206.

AMA Style

Sang-Yeon Lee, In-Bok Lee, Uk-Hyeon Yeo, Rack-Woo Kim, Jun-Gyu Kim. Optimal sensor placement for monitoring and controlling greenhouse internal environments. Biosystems Engineering. 2019; 188 ():190-206.

Chicago/Turabian Style

Sang-Yeon Lee; In-Bok Lee; Uk-Hyeon Yeo; Rack-Woo Kim; Jun-Gyu Kim. 2019. "Optimal sensor placement for monitoring and controlling greenhouse internal environments." Biosystems Engineering 188, no. : 190-206.

Journal article
Published: 01 November 2019 in Biosystems Engineering
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The wind pressure coefficient (Cp) can be divided into a mean wind pressure coefficient (Cp, mean) and peak wind pressure coefficient (Cp, peak). In this study, the Cp, mean and Cp, peak values of single-span greenhouses were estimated using time-dependently computed large eddy simulation (LES) of the computational fluid dynamics (CFD) model. First, the Cp, mean and Cp, peak values of single-span greenhouses were measured through a wind tunnel test considering various experimental conditions, such as the roof slope and roof curvature radius. The CFD-computed Cp, mean and Cp, peak values were compared with those measured in the wind tunnel for the validation of the CFD model. Especially, the computed Cp, mean values using the LES model were compared with the computed Cp, mean values using the RANS model performed by Kim, Lee, and Kwon (2017). Consequently, the LES model predicted the Cp, mean values more accurately than those predicted by the RANS. In addition, the Cp, peak values computed using the LES model showed only fine differences with those measured in some other regions; however, the overall tendency was similar between the measured and computed Cp, peak values. From these results, it was determined that the LES model can properly predict the Cp, peak values as well as the Cp, mean values.

ACS Style

Rack-Woo Kim; In-Bok Lee; Uk-Hyeon Yeo; Sang-Yeon Lee. Estimating the wind pressure coefficient for single-span greenhouses using an large eddy simulation turbulence model. Biosystems Engineering 2019, 188, 114 -135.

AMA Style

Rack-Woo Kim, In-Bok Lee, Uk-Hyeon Yeo, Sang-Yeon Lee. Estimating the wind pressure coefficient for single-span greenhouses using an large eddy simulation turbulence model. Biosystems Engineering. 2019; 188 ():114-135.

Chicago/Turabian Style

Rack-Woo Kim; In-Bok Lee; Uk-Hyeon Yeo; Sang-Yeon Lee. 2019. "Estimating the wind pressure coefficient for single-span greenhouses using an large eddy simulation turbulence model." Biosystems Engineering 188, no. : 114-135.

Journal article
Published: 01 November 2019 in Biosystems Engineering
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The greenhouse design standard for South Korea is under revision to ensure the structural safety of greenhouses in response to strong winds. In order to ensure that suitable design standards for structural safety are adopted, wind load criteria for a range of countries have been analysed. The provisions for wind load, correction factors, and wind pressure coefficients were analysed using greenhouse design standards from Korea, China, Japan, United States of America (USA), and European Union (EU) (CEN, 2001; JGHA, 2016; MAFRA, 1999; MOHURD, 2017; NGMA, 2004). Although the calculations are similar throughout these greenhouse design standards (CEN, 2001; JGHA, 2016; MAFRA, 1999; MOHURD, 2017; NGMA, 2004), different factors are used to calculate wind load. From the analysed data, a structural analysis was conducted to evaluate the structural safety of the designs for wind load. The results indicated that a relatively rigid member should be used for a greenhouse framework constructed using the greenhouse design standard from USA (NGMA, 2004) and that a relatively inexpensive greenhouse could be constructed using the greenhouse design standard from Japan (JGHA, 2016).

ACS Style

Rack-Woo Kim; In-Bok Lee; Uk-Hyeon Yeo; Sang-Yeon Lee. Evaluation of various national greenhouse design standards for wind loading. Biosystems Engineering 2019, 188, 136 -154.

AMA Style

Rack-Woo Kim, In-Bok Lee, Uk-Hyeon Yeo, Sang-Yeon Lee. Evaluation of various national greenhouse design standards for wind loading. Biosystems Engineering. 2019; 188 ():136-154.

Chicago/Turabian Style

Rack-Woo Kim; In-Bok Lee; Uk-Hyeon Yeo; Sang-Yeon Lee. 2019. "Evaluation of various national greenhouse design standards for wind loading." Biosystems Engineering 188, no. : 136-154.

Journal article
Published: 31 August 2019 in Biosystems Engineering
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Due to the cold stress experienced by pigs, and the increased energy load during winters and the changes from winter to spring and summer to autumn, it is difficult to provide sufficient ventilation in pig houses. These factors can result in a poor internal environment. Therefore, fundamental measures to increase the ventilation rate and a corresponding analysis of the effects were needed to improve internal rearing environment. Due to the characteristics of invisible air, it was difficult to analyse the aerodynamic characteristics inside a pig house by field experiment. Computational fluid dynamics (CFD) has been used to overcome such limitations for the last 30 years. In this study, environmental monitoring (air temperature, humidity, etc.) in a commercial pig house were conducted to identify environmental problems. After this, CFD validated models were designed and evaluated to find effective solutions, by changing the conditions of the pig house air inlets and outlets (air buffer space, inlet duct, and exhaust fan). Compared with the conventional ventilation system of the experimental pig house, adjusting the hole spacing of the inlet duct and installing a roof–chimney exhaust fan did not significantly improve the rearing environment. However, when an air buffer space was installed just before the location of the inlet on the sidewall, the air temperature flowing through the air buffer space increased making it possible to supply more than twice the external air to the pig house, while maintaining the air temperature distribution at the height of the animal-occupied zone.

ACS Style

Uk-Hyeon Yeo; In-Bok Lee; Rack-Woo Kim; Sang-Yeon Lee; Jun-Gyu Kim. Computational fluid dynamics evaluation of pig house ventilation systems for improving the internal rearing environment. Biosystems Engineering 2019, 186, 259 -278.

AMA Style

Uk-Hyeon Yeo, In-Bok Lee, Rack-Woo Kim, Sang-Yeon Lee, Jun-Gyu Kim. Computational fluid dynamics evaluation of pig house ventilation systems for improving the internal rearing environment. Biosystems Engineering. 2019; 186 ():259-278.

Chicago/Turabian Style

Uk-Hyeon Yeo; In-Bok Lee; Rack-Woo Kim; Sang-Yeon Lee; Jun-Gyu Kim. 2019. "Computational fluid dynamics evaluation of pig house ventilation systems for improving the internal rearing environment." Biosystems Engineering 186, no. : 259-278.

Journal article
Published: 01 January 2019 in Protected horticulture and Plant Factory
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ACS Style

Jae Seung Noh; Yu Yong Kim; Young Ji Yoo; Jin Kyung Kwon; In Bok Lee; Rack Woo Kim; Jun Gyu Kim. Development of Air Flow Simulator in Agricultural Facility based on Virtual Reality. Protected horticulture and Plant Factory 2019, 28, 16 -27.

AMA Style

Jae Seung Noh, Yu Yong Kim, Young Ji Yoo, Jin Kyung Kwon, In Bok Lee, Rack Woo Kim, Jun Gyu Kim. Development of Air Flow Simulator in Agricultural Facility based on Virtual Reality. Protected horticulture and Plant Factory. 2019; 28 (1):16-27.

Chicago/Turabian Style

Jae Seung Noh; Yu Yong Kim; Young Ji Yoo; Jin Kyung Kwon; In Bok Lee; Rack Woo Kim; Jun Gyu Kim. 2019. "Development of Air Flow Simulator in Agricultural Facility based on Virtual Reality." Protected horticulture and Plant Factory 28, no. 1: 16-27.

Journal article
Published: 01 November 2018 in Fusion Engineering and Design
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This paper proposes an optimization model for the scheduling of the fuel cycle of a fusion power plant. The objective of the problem is to minimize the tritium working inventory in the Isotope Separation System under periodic demand, thereby solving problems associated with high inventories. The model is formulated as a mixed integer nonlinear programming problem based on the state-task network approach. The proposed model is applied to inductive, hybrid, and non-inductive tokamak operation modes. With proposed case studies, the model is expected to provide many useful insights to determine the optimum scheduling results providing information on flow pattern, flow rate, and flow timing between equipment while minimizing tritium working inventory.

ACS Style

Suh-Young Lee; Min Ho Chang; Sei-Hun Yun; Jin-Kuk Ha; In-Beum Lee; Euy Soo Lee. Optimal scheduling model to minimize tritium inventory level in fuel cycle of tritium plant. Fusion Engineering and Design 2018, 136, 747 -751.

AMA Style

Suh-Young Lee, Min Ho Chang, Sei-Hun Yun, Jin-Kuk Ha, In-Beum Lee, Euy Soo Lee. Optimal scheduling model to minimize tritium inventory level in fuel cycle of tritium plant. Fusion Engineering and Design. 2018; 136 ():747-751.

Chicago/Turabian Style

Suh-Young Lee; Min Ho Chang; Sei-Hun Yun; Jin-Kuk Ha; In-Beum Lee; Euy Soo Lee. 2018. "Optimal scheduling model to minimize tritium inventory level in fuel cycle of tritium plant." Fusion Engineering and Design 136, no. : 747-751.

Journal article
Published: 22 September 2018 in Biosystems Engineering
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Precise ventilation control of broiler houses is essential to effectively exhaust pollutants and attain the required breeding environment. However, the ventilation rate used in practise is always lower than the desired or designed value because of difficulties in measuring the pressure difference between the indoor and outdoor pressure of the facility. In this study, a new formula was developed to estimate the total ventilation rate for mechanically ventilated broiler houses using the number of operating fans and the slot opening rate, both of which are relatively easy to measure in practice. The proposed formula was derived from the in-situ fan performance curve and the discharge coefficient, which represent the ventilation characteristics of the exhaust fans and slot openings respectively. This was evaluated through a field experiment and a computational fluid dynamics (CFD) simulation. The measured ventilation rate was 24.1–26.6% lower than the desired ventilation rate showing that the in-situ fan performance curve was 33.7 Pa lower on average than the designed fan performance curve provided by the manufacturer. The distribution of static pressure in the broiler house was analysed using CFD models and it was found that the new formula could be applied to broiler houses having difference lengths.

ACS Style

Gwanyong Park; In-Bok Lee; Uk-Hyeon Yeo; Taehwan Ha; Rack-Woo Kim; Sang-Yeon Lee. Ventilation rate formula for mechanically ventilated broiler houses considering aerodynamics and ventilation operating conditions. Biosystems Engineering 2018, 175, 82 -95.

AMA Style

Gwanyong Park, In-Bok Lee, Uk-Hyeon Yeo, Taehwan Ha, Rack-Woo Kim, Sang-Yeon Lee. Ventilation rate formula for mechanically ventilated broiler houses considering aerodynamics and ventilation operating conditions. Biosystems Engineering. 2018; 175 ():82-95.

Chicago/Turabian Style

Gwanyong Park; In-Bok Lee; Uk-Hyeon Yeo; Taehwan Ha; Rack-Woo Kim; Sang-Yeon Lee. 2018. "Ventilation rate formula for mechanically ventilated broiler houses considering aerodynamics and ventilation operating conditions." Biosystems Engineering 175, no. : 82-95.

Book chapter
Published: 02 August 2018 in 16th European Symposium on Computer Aided Process Engineering and 9th International Symposium on Process Systems Engineering
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This study proposes a decision-making tool for stochastic planning of a carbon capture utilization and sequestration (CCUS) network by optimizing conflicting objectives under uncertainties. A scenario-based two-stage stochastic model is formulated to handle various sources of uncertainty, such as fluctuation of CO2 emission level, variability of construction and operation cost, and unpredictable events. In the model, a concept of downside risk is introduced to evaluate the risk caused by uncertainties. This model holds its strength in that it provides an intuitive decision-making algorithm for financial impact, environmental impact, and risk on a CCUS network within a single framework. To evaluate environmental impact, Life Cycle Assessment method, specifically Ecoindicator 99, considering all contributions caused by installation and operations over a whole chain of CCUS is applied. By formulating as a stochastic multi-objective optimization model, it can evaluate the trade-off between total annual benefit with financial risk considering an environmental impact. This problem is formulated as a mixed integer linear program model with linear constraints. A case study for the industrial complex on the east coast of Korea in 2030 is presented to illustrate the applicability of the proposed model.

ACS Style

Suh-Young Lee; In-Beum Lee; Jeehoon Han. Optimal design under uncertainty of carbon capture, utilization, and sequestration network considering benefit, environmental impact, and preference on risk. 16th European Symposium on Computer Aided Process Engineering and 9th International Symposium on Process Systems Engineering 2018, 44, 1585 -1590.

AMA Style

Suh-Young Lee, In-Beum Lee, Jeehoon Han. Optimal design under uncertainty of carbon capture, utilization, and sequestration network considering benefit, environmental impact, and preference on risk. 16th European Symposium on Computer Aided Process Engineering and 9th International Symposium on Process Systems Engineering. 2018; 44 ():1585-1590.

Chicago/Turabian Style

Suh-Young Lee; In-Beum Lee; Jeehoon Han. 2018. "Optimal design under uncertainty of carbon capture, utilization, and sequestration network considering benefit, environmental impact, and preference on risk." 16th European Symposium on Computer Aided Process Engineering and 9th International Symposium on Process Systems Engineering 44, no. : 1585-1590.