• Korean Journal of Agricultural Science
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• v.41 no.3
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• pp.251-258
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• 2014

In order to set up the basic environmental control systems which the new concept greenhouses have to equip, greenhouse characteristics, environmental management and control systems in domestic glasshouses and plastic houses were investigated and analyzed comparatively. Survey results on the width, length, eaves height, and the number of spans etc. showed that glasshouses were bigger than plastic houses significantly. New concept greenhouses claim to be plastic houses, but it will be reasonable to follow the specifications of the glasshouse. Specifications to be applied to new concept greenhouses were proposed as follows; hot water heating systems, aluminum screens as the thermal curtain, evaporative cooling systems, roof vents on the ridge, circulation fans, $CO_2$ enrichment, hydroponic systems, and automatic irrigation control systems. Environmental measurement systems for the indoor and outdoor temperature, humidity, light, wind speed and indoor $CO_2$ concentration have to be fully equipped. The automatic control system has to be as a complex environmental control system, not a single item control system. Also, for stable dissemination, domestically producing complete greenhouse control system should be made as soon as possible.

• Journal of the Korean Solar Energy Society
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• v.22 no.4
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• pp.44-50
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• 2002

Photosynthesis of plants is effective in the range of 550 to 700 nm of the wavelength of solar irradiation. If the conversion of ultraviolet to the above mentioned region is possible, the photosynthesizing ability is expected to be enhanced. $Eu^{3+}$ doped soda-lime bulk and $TiO_2-SiO_2$ sol-gel coated glasses were prepared and their spectroscopic properties were studied. The absorption and emission spectra for the specimens were measured with the changes of wavelength and Eu ion concentration in the range of the wavelength of 300 to 700nm. The transmittance intensity of visible light through the bulk glass and the coated one was unchanged with the addition of Eu element. The emission spectrum intensity of $Eu^{3+}$ was found to be the maximum at 618 nm which is a transition of $^5DO{\rightarrow}^7F_2$. Additionally, it was shown that the intensity was linearly increased up to 10% of the Eu concentration.

• KIEAE Journal
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• v.13 no.3
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• pp.97-104
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• 2013

This proposed simulation-based design study is based on the design of residential high-rise buildings in South-Korea. the purpose of this study is to evaluate the amount of daylighting performance passing through building glazing according to sky conditions, orientation of windows and each space of Apartment buildings. The clear sky includes sunshine and is intense and brighter at the horizon than at the zenith, except in the area around the sun. Daylight received within a building is directly dependent upon the sun's position and the atmospheric conditions. Orientation of the building generally used to refer to solar orientation which is the siting of building with respect to solar access. Although any building will have different orientations for its different sides, the orientation can refer to a particular room, or to the most important facade of the building. north-facing windows receive twice the winter sun than east and west facing windows, allowing light and warmth into the home. They can be easily shaded from the high summer sun to help keep the house cool. Ideally, the glazing area should be between 10-25% of the floor area of the room. This paper was calculated by a Desktop Radiance program. The space dimensions were based on a unit module of real constructed apartment having divided into five sections such as living room, room1, room2, room3 and kitchen.

• Korean Institute of Interior Design Journal
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• v.24 no.5
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• pp.31-41
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• 2015

The objective of this research is to investigate the artistic meaning of "infinity," manifested by the fourth dimensional value in the genres of photography and architecture, by analyzing how Sugimoto Hiroshi's photographic spatio-temporal infinity transfers to his architectural approaches. The research is initiated by scrutinizing the themes, characteristics, techniques, and artistic meaning of Sugimoto's famous photographic series, including "Seascapes," "Theatres," and "Architecture"; the concept of infinity can be defined as infinite divergence and infinitesimal convergence between antithetical concepts in time, space, and being. Sugimoto's photographic works display "temporal infinity" by connecting ancient times, the present, and the future; "spatial infinity" by offering the potential for transformation from flat photographs into infinite three-dimensional space and fourth-dimensional concepts through time; and "existential infinity" of life and death by making us think about being and essence, being and time, and origin and religion. These perspectives are also used to analyze Sugimoto's architectural works, such as "Appropriate Proportion" and "Glass Tea House Mondrian." As a result, the research finds that in Sugimoto's architectural approaches, spatio-temporal infinity between antithetical values is manifested through the concept of origin, geometric form, extended axis, immaterial threshold, transparent materiality, and connectivity of light and shadow, provoking our existence to transcend into infinity itself.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2009.06a
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• pp.463-466
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• 2009

The objective of this study is to analyze the process of lighthouse in the Daehan Empire. It has been considered that the lighthouse of the Daehan Empire had been built by Japanese lighthouse engineer Ishibashi Ayahico. But in this study, the rule of John Reginald Harding as an light house engineer in Korea from 1899 to 1906 will be said. It was considered that the first lighthouses in Korea were built in Incheon in 1903. But because John Reginald Harding came and designed lighthouse at Mokpo 1899, we need to research more carefully. And also many lighthouses have been placed along the coastline by selection by John Reginald Harding. So Korean Lighthouses had been developed by Ishibashi Ayahico as well as John Reginald Harding.

• Nuclear Engineering and Technology
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• v.52 no.5
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• pp.878-888
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• 2020

This paper presents the validation of UNIST in-house Monte Carlo code MCS used for the high-fidelity simulation of commercial pressurized water reactors (PWRs). Its focus is on the accurate, spatially detailed neutronic analyses of startup physics tests for the initial core of the Watts Bar Nuclear 1 reactor, which is a vital step in evaluating core phenomena in an operating nuclear power reactor. The MCS solutions for the Consortium for Advanced Simulation of Light Water Reactors (CASL) Virtual Environment for Reactor Applications (VERA) core physics benchmark progression problems 1 to 5 were verified with KENO-VI and Serpent 2 solutions for geometries ranging from a single-pin cell to a full core. MCS was also validated by comparing with results of reactor zero-power physics tests in a full-core simulation. MCS exhibits an excellent consistency against the measured data with a bias of ±3 pcm at the initial criticality whole-core problem. Furthermore, MCS solutions for rod worth are consistent with measured data, and reasonable agreement is obtained for the isothermal temperature coefficient and soluble boron worth. This favorable comparison with measured parameters exhibited by MCS continues to broaden its validation basis. These results provide confidence in MCS's capability in high-fidelity calculations for practical PWR cores.

• Nuclear Engineering and Technology
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• v.53 no.10
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• pp.3264-3274
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• 2021

In a severe accident of light water reactor (LWR), molten core material (corium) can be released into the wet cavity, and a fuel-coolant interaction (FCI) can occur. The molten jet with high speed is broken and fragmented into small debris, which may cause a steam explosion or a molten core concrete interaction (MCCI). Since the premixing stage where the jet breakup occurs has a large impact on the severe accident progression, the understanding and evaluation of the jet breakup phenomenon are highly important. Therefore, in this study, the jet breakup simulations were performed using the Smoothed Particle Hydrodynamics (SPH) method which is a particle-based Lagrangian numerical method. For the multi-fluid system, the normalized density approach and improved surface tension model (CSF) were applied to the in-house SPH code (single GPU-based SOPHIA code) to improve the calculation accuracy at the interface of fluids. The jet breakup simulations were conducted in two cases: (1) jet breakup without structures, and (2) jet breakup with structures (control rod guide tubes). The penetration depth of the jet and jet breakup length were compared with those of the reference experiments, and these SPH simulation results are qualitatively and quantitatively consistent with the experiments.

• Journal of the Regional Association of Architectural Institute of Korea
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• v.20 no.6
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• pp.63-70
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• 2018

This study is aimed to reflect the current status survey, analysis and response of 10 railway stations using geographical names in one of 19 stations located on Gyeongbu, Honam and Chungbuk line. Most railway stations in the study have shown normal images that are close to the standard type by selecting similar building materials rather than reflecting geographical features. Aside from the shape of the traditional Korean house in Cheongju, almost all newly constructed stations tend to incorporate light gray plating material on their modern exterior to produce Family look design as a railroad station. According to a survey of the sensitivity of the station's name, Osong Station was 73.6 percent, Gyeryong Station 67.3 percent, Heukseok-ri Station was 64.5 percent, Shintan-jin 62.6 percent, and Yeonsan Station 57 percent, more than half. Therefore, the results of the five stations were presented as a calculation and proposed design release focusing on the facades of each station. Each of these stations suggested a way to express the facade design image, considering the railway operation status of Korea Railroad, the area of the station and other surroundings.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.34 no.5
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• pp.27-34
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• 2018

Concrete placed under hot weather condition suffers from larger slump loss, rapid moisture evaporation due to high air temperature. Proper measures for material, transportation and curing should be taken to prevent the quality deterioration of the concrete under hot weather condition. In Korea, Although the period of hot weather concrete in Korea occupies only 2 months, there are a lot of quality problems including plastic, drying shrinkage and cold joint. Therefore, the objective of this paper is to investigate and compare the temperature history and crack occurrence of the concrete, which was placed in the actual apartment house construction field under hot weather condition, in response to the application of surface covered curing blankets including PE film, single layer clear bubble sheet, white colored bubble sheet and aluminum metalized bubble sheet. Test results indicated that the application of white colored bubble sheet and aluminum metalized bubble sheet showed most favorable results in terms of reduction in temperature rise and crack occurrence as well as easiness in handling. But, due to light reflection by aluminum metalized bubble sheet, it is believed that white colored bubble sheet is preferable.

• Nuclear Engineering and Technology
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• v.54 no.8
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• pp.2924-2932
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• 2022

Motivated by learning from experience and exploiting existing knowledge in civil nuclear operations, we have developed in-house generic Probabilistic Safety Assessment (PSA) models for pressurized and boiling water reactors. The models are computationally light, handy, transparent, user-friendly, and easily adaptable to account for major plant-specific differences. They cover the common internal initiating events, frontline and support systems reliability and dependencies, human-factors, common-cause failures, and account for new factors typically overlooked in many PSAs. For quantification, the models use generic US reliability data, precursor analysis reports, the ETHZ Curated Nuclear Events Database, and experts' opinions. Moreover, uncertainties in the most influential basic events are addressed. The generated results show good agreement with assessments available in the literature with detailed PSAs. We envision the models as an unbiased framework to measure nuclear operational risk with the same "ruler", and hence support inter-plant risk comparisons that are usually not possible due to differences in plant-specific PSA assumptions and scopes. The models can be used for initial risk screening, order-of-magnitude precursor analysis, and other research/pedagogic applications especially when no plant-specific PSAs are available. Finally, we are using the generic models for large-scale precursor analysis that will generate big picture trends, lessons, and insights.