• KOREAN JOURNAL OF CROP SCIENCE
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• v.58 no.3
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• pp.324-330
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• 2013

One of the abundant biomass for bioenergy production is thought to be agricultural by-products produced annually. The purpose of this study were to provide basic information about the changes of the moisture contents and chemical compositions for storage periods and bale types of rice straw, and it was attempted for the first time. The bale types of rice straw which were harvest in October 2011, were the square bale, the round bale, and the wrapped round bale type with plastic, respectively. Each of bale were stored in house, outdoor, and rain sheltering facilities condition for 1 year. The moisture contents and chemical compositions for each bale type are investigated for the 3-storage stages (0, 6, 12 month). While the moisture contents of the square and round bales stored in house condition were ranged from 20~25%, the square bale stored under the rain shelter facilities was showed the lowest moisture content less than 20% during the storage periods. For the chemical compositions, the cellulose and hemicellulose contents of rice straw bale stored in outdoor condition were decreased with the storage periods. However, in house condition, the chemical compositions of the square and round bales were slightly increased at the middle and the end of storage stages (6 and 12 months) compared with the initial storage stage (0 month). In conclusion, while optimum and favorable storage conditions of agricultural by-products is a house storage of the bale with plastic, if the bale can stored at outdoor, water penetration prevention such as the rain shelter facilities is required.

• Food Science and Preservation
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• v.13 no.4
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• pp.421-426
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• 2006

Preservation stability of the extract from dried green tea produced in Jeju, extracted at $55^{\circ}C$ for 15 min and bottled in PET container after filtration and then settled at $4^{\circ}C$, indoor at room temperature and outdoor, respectively, was estimated. Color L-value was almost constant but color of the extract became darkened during storage, especially in indoor storage. Main catechins of green tea extract were (-)-epigallocatechin, (-)-epigallocatechin gallate, epicatechin, (+)-catechin, epicatechin gallate in order, and the content of epigallocatechin was 53.8%. Nevertheless total catechin content was not changed in cold storage, and $4.7\sim10%$ of total catechins were reduced in outdoor or indoor storage after 14 weeks. Caffeine content were increased but total polyphenols were not changed largely during storage. Election donating abilities (EDA) showed more than 60% without influence of storage conditions and periods. Nitrite scavenging abilities (NSA) showed more than 90% at pH 1.2, but those were decreased gradually as pH increased, and then disappeared at pH 6.0. Color, polyphenols, antioxidant activities of extract were not so changed for more than 3 months. Microbial growth was not shown during same periods, due to heat treatment of the extracts at $95^{\circ}C$ for 10 min.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.10
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• pp.6759-6765
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• 2015

In this study, the effects of control strategies of night-purge control system on control characteristics and energy consumption for central cooling system in building are researched by simulation. The start time and set-point temperature for night-purge control with outdoor temperature changes and building cold storage performance are obtained. The system analysis modelling is done by using TRNSYS program package, and the control performances with suggested night-purge control method are compared with the existing control ones. As a result, the suggested night-purge control method shows maximum 16.8% and 28.6% energy saving in comparison with existing control method and conventional one without night-purge control, respectively.

• Journal of Advanced Marine Engineering and Technology
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• v.41 no.1
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• pp.99-104
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• 2017

This study evaluated the heating performance of a hybrid heat pump system. The system was installed in a $100-m^2$ greenhouse to utilize surplus solar energy. A hybrid heat pump system was installed at Jocheon-ri, Jeju Island, for an empirical evaluation of the performance. The system consists of a heat storage tank and plate heat exchangers for several heat exchanges between the greenhouse and heat pump or storage tank. The system uses R410a as the working fluid and is controlled automatically by a defined set temperature of the greenhouse. This system incorporates two kinds of heat sources: outdoor air and a storage tank that collects heat from the topside of the greenhouse. The results showed that the heating capacity was 19.9 kW in the outdoor air source mode and 21.4 kW with direct heating from hot water in the thermal storage tank. These results are very similar to those of a previous study.

• Asian Journal of Innovation and Policy
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• v.12 no.3
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• pp.277-303
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• 2023

The importance of ecosystem service such as green spaces has risen due to restrictions on outdoor activities amid the climate crisis and COVID-19. While gardens significantly impact economic development, quality of life, and social well-being, comprehensive studies on their multidimensional values are lacking. This research categorizes garden values into social, cultural, environmental, and health dimensions and proposes an integrated assessment framework that introduces detailed elements and evaluation methods. An empirical assessment of carbon storage index in two Korean gardens, Semiwon and Juknokwon, reveals Semiwon's higher carbon storage per unit area. The proposed framework, emphasizing a quantitative approach, enables cross-national and regional comparisons, contributing to a broader understanding and evaluation of garden values beyond specific facilities.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.24 no.2
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• pp.190-195
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• 2012

In this study, as a complementary study of the former study on indoor thermal environment in a tower type apartment house at tropical nights, a field measurement was conducted in winter season. Mainly, characteristics of heat storage and heat emission in apartment structures, in this study, were investigated. As results, indoor air temperature was changed in the range of $22.5^{\circ}C{\pm}1.0^{\circ}C$, and followed not the change of outdoor air temperature but the changed pattern of floor surface temperature. Wall surface temperature was unresponsive to the change of floor surface temperature compared with the change of indoor air temperature because wall structure was composed of concrete which has large heat capacity, and was changed in the range of $22.3^{\circ}C{\pm}0.6^{\circ}C$. Heat was stored continuously into the structures of wall and ceiling through the measurement term. and this means that a large heat capacity of the apartment structure acts as a disadvantage in winter season, too. As a total review of the study with the former study, a large heat capacity of the apartment structure acts against indoor thermal comfort in winter season as well as in summer season.

• Proceedings of the SAREK Conference
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• 2006.06a
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• pp.80-85
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• 2006

The peak demand of electricity in summer season mainly comes from the day time cooling loads. Ice thermal Storage System (ITSS) uses off-peak electricity at night time to make ice for the day time cooling. In order to maximize the use of cold storage in ITSS, the estimation of day time cooling load for the building is necessary. In this study, we present a method of cooling load estimation using 5 years of normalized outdoor temperature, relative humidity, and the building construction data. We applied the hourly-based estimation to a general hospital building with relatively less sudden heat exchange and the results are compared with the measured cooling load of the building. The results show that the cooling loads estimation depends on the indoor cooling design temperature of the building.

• Journal of Conservation Science
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• v.24
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• pp.75-83
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• 2008

In order to assess antifungal activity of a wooden storage box, which was made of Paulownia tomentosa and used for keeping ancient documents, antifungal activity of volatile organic compounds emitted from the box was investigated along with qualitative analysis on major substances of the compounds. After collecting floating microorganisms inside air tester, the fungal activity was assessed by counting the number of colonies growing on TSA media. Compared to the control which collected 85 colonies from outdoor, 72 colonies were observed showing reduction rate of 14.82%. Through GC/MS and TDS system analysis, limonene was detected from the volatile organic compounds as characteristic features. When the fungal activity was assessed through fumigation by adding natural biocide BI and BII containing eugenol and anethole as major substances, both biocides showed a strong fungal activity with respectively 92.6%(inside the box) and 99.9%(outdoor) of reduction rate. Although these results didn't clarify antifungal activity of the volatile organic compounds emitted from the Paulownia-wood storage box and their functional components, it was at least confirmed that there is application possibility of natural biocide to use for preservation of ancient documents with increased efficiency in controlling pests of wooden storage boxes.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.24 no.4
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• pp.416-424
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• 2014

Objectives: The objective of this study is to analyze the predominant microorganisms in the industry treating MWFs(Metal working fluids). Methods: The bacteria and fungi were collected by agar plate impaction and bulk MWFs in storage tank at 54 sites in 9 shops in South Korea. The dominant bacteria and fungi isolated from agar media were identified by fatty acid analysis and morphological analysis, respectively. Results: Totally 111 dominant bacteria were identified in the process, outdoor, and bulk MWFs. The predominant bacterial genus was Micrococcus and Bacillus in the process and outdoor, Pseudomonas in bulk MWF. Among the identified 119 strains of fungi, Cladosporium and Penicillium genus were dominated. The ratios of bacteria designated biosafety level 2 and 1 were 30% and 21%, respectively. Conclusions: This study has investigated the dominant microorganisms in soluble MWF using industry. And it was useful that the qualitative evaluation method along with quantitative analysis for better understanding of the biological factors in the work environment.

• Journal of the Korean Solar Energy Society
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• v.37 no.1
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• pp.71-80
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• 2017

A Data center houses a large number of server computers, storage and etc in racks. With the rapid increase of heat generation rates per rack in a data center, energy consumption rates for cooling have been increased year by year. In this study, energy conservation effects of a MOA (multi-stage outdoor air enabled) cooling system in a data center has been investigated when it is applied to 5 different locations, Korea. As results, Energy conservation effects of the MOA cooling system was achieved at about 20% to 30%. Humidifier operation time was 40 to 55 days when supply air temperature was maintained at 13, and humidity condition was kept within the allowed range even though humidifier was off. Furthermore, humidification was not needed when supply air temperature was maintained at $25^{\circ}C$. In selected 5 locations in Korea, the difference of regional climatic conditions affected no more than 5% in cooling energy consumption rates.