• Journal of Korean Society for Quality Management
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• v.47 no.3
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• pp.425-435
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• 2019

Purpose: The purpose of this study was to resolve the Naval ship's Local Operation Panel(LOP) malfunction problems which caused by overheating in summer season and dispatching to equatorial regions. Methods: Instead of using dual type heat insulation materials(consist with ceramic wool and glass wool), aerogel heat insulation materials were used for decreasing heat emissions from gas-turbine heat waste steam pipes passing water-jet- room. Experiment and Computational analysis of heat flow were conducted to analyze the internal room temperature changes. Results: The results of this study are as follows; The aerogel heat insulation materials suppress heat emission more efficiently than dual type insulation materials. The cold surface temperature of insulation was far more decreased and internal room, LOP surface temperature also showed significant results too. Conclusion: The substituted heat insulation materials appeared remarkable performance in decreasing room temperature that it could be used for suppressing the LOP overheatings and malfunctions.

• The Korean Journal of Mycology
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• v.19 no.4
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• pp.292-298
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• 1991

Volatile aroma concentrates of Pleurotus sajor-caju which stored at $20^{\circ}C$ incubator and cold room were obtained by simultaneous distillation-extraction method. The volatile components were identified by combined capillary gas chromatography-mass spectrometry and comparison of retention data on GC of those authentic compounds. Storage at room temperature resulted in significant decreased in their total aroma contents, whereas little changes at cold storage foured, even though appreciable changes were observed in GC pattern between the control and stored samples. Of 38 components identified, ${\delta}-decalactone$ increased while rest of the volatiles decreased rapidly during storage at room temperature, but at cold storage 2-methyl butanal, 1-octen-3-ol, cis,cis-1,5-octadien-3-ol and pentadecanoic acid decreased while 3-octanone, 1-octen-3-one, 3-octanol and 5-undecanol increased with the storage time. The weight losses and organoleptic properties changed extremely by the storage under room temperature, on the other hand, slight changes were found in cold storage.

• Korean Journal of Plant Resources
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• v.11 no.2
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• pp.136-141
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• 1998

To give some information on the harvest and storage of Chinese yam (Dioscorea opposita), the experiment was done to examine the effect of its harvesting date and storage method on tuber weight, tuberrelated characters during the storageor at the end of storage. The yam tubers harvested 4 times at 20 days interval from Oct. 15 were stored with different storage methods(pit, room and cold temperature) and on Mar.15. all the characters were measured. Fresh weight of the tuber harvestedafter Nov. 5 and stored were greater than that done on Oct. 15 while dry tuber weight did not have any difference between the harvesting dates. The fresh weigth done directly from the field on Mar. 15 was higher compared to the other harvesting dates owing to its higher moisture content. The rate of sound tuber stored at room or cold temperature condition was higher than that at the field at which the rate was greater at the harvest after late nov. compared to the earlier harvests. Although the two storages were similar at sound tuber rates and marketable yield, the tuber weight was more reduced when stored at room temperature than when done at cold temperature . Brightness and value 'b' of chromaticaity realted to the tuber coloring and sugar content were higher but moisture content was lowerwhen harvested on Oct. 15 than the other havesting dates. All the characteristics realted to the marketability after storage were nearly same when stored at room and cold temperature. Value 'a' of chromaticity and sugar content were higher when harvest on Mar. 15 than when harvested before Dec. 15 but the 'b' value and mositure content were reverse results.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.20 no.12
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• pp.8-15
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• 2021

Cold forging is a method in which molding is performed at room temperature. It has a high material recovery rate and dimensional precision and produces excellent surface quality, and it is mainly used for the production of bolted or housing products. The lifespan of cold forging molds is generally determined by the wear of the mold, plastic deformation of the mold, and fatigue strength. Cold forging molds are frequently damaged due to fatigue destruction rather than wear and plastic deformation in a high-temperature environment as it is molded at room temperature without preheating the raw material and mold. Based on the results analyzed through FEM, an effective mold structure design method was proposed by analyzing the changes in tensile and compressive stresses on molds according to the number of molds and reinforcement rings and comparing the product geometry and mold stress using three existing mold models.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.15 no.9
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• pp.1971-1978
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• 2011

In RFID-based cold-storage systems, product locations are recognized as the logical locations of RFID readers which are attached to the entrance of the cold rooms. However, through these methods, product locations can be incorrect in many different situations of a storage. Cold storage rooms have a huge rage in temperature, and the product in the cold-storage spoils easily. Therefore, highly precise product locations is very important for the product quality In this paper, a new approach is suggested to manage the storage location inaccuracy by adding two readers to existing forklift and attaching RFID tags to the ceiling. One reader recognizes ceiling tags to acquire location data, and the other recognizes product tags to acquire product detail data loaded on the forklift. The product can be seamlessly tracked and traced in realtime by monitoring and analyzing data gathered from these readers. Through the proposed location management method, the effectiveness of the product management in cold-storage can be improved consequently.

• Progress in Superconductivity and Cryogenics
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• v.15 no.1
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• pp.45-50
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• 2013

Closed-loop J-T (Joule-Thomson) refrigeration cycle is advantageous compared to common open loop $N_2$ decompression system in terms of nitrogen consumption. In this study, two closed-loop pure $N_2$ J-T refrigeration systems with sub-atmospheric device for cooling High Temperature Superconductor (HTS) power cable are investigated. J-T cooling systems include 2-stage compressor, 2-stage precooling cycle, J-T valve and a cold compressor or an auxiliary vacuum pump at the room temperature. The cold compressor and the vacuum pump are installed after the J-T valve to create sub-atmospheric condition. The temperature of 67 K is possible by lowering the pressure up to 24 kPa at the cold part. The optimized hydrocarbon mixed refrigerant (MR) J-T system is applied for precooling stage. The cold head of precooling MR J-T have the temperature from 120 K to 150 K. The various characteristics of cold compressor are invstigated and applied to design parameter of the cold compressor. The Carnot efficiency of cold compressor system is calculated as 16.7% and that of vacuum pump system as 16.4%. The efficiency difference between the cold compressor system and the vacuum pump system is due to difference of enthalpy change at cryogenic temperature, enthalpy change at room temperature and different work load at the pre-cooling cycle. The efficiency of neon-nitrogen MR J-T system is also presented for comparison with the sub-atmospheric devices. These systems have several pros and cons in comparison to typical MR J-T systems such as vacuum line maintainability, system's COP and etc. In this paper, the detailed design of the subcooled $N_2$ J-T systems are examined and some practical issues of the sub-atmospheric devices are discussed.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.25 no.1
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• pp.1-10
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• 2022

This study was conducted to investigate the germination characteristics through the temperature change treatment compared to the general room temperature immersion treatment of the native species, the Larix kaempferi, and the Berula platyphyllavar. japonica seeds, and to obtain basic data for the production of healthy seedlings with high productivity and efficiency. As a result, the germination rate of the larch seeds showed a significant difference according to room temperature and temperature immersion treatment, and the average germination days of the birch seeds showed a significant difference according to room temperature immersion and temperature immersion treatment. On the other hand, there was no significant difference in germinal uniformity. The results of the study are as follows. First, the results of the analysis of the fallen leaves were the highest germination rate in the treatment of 1.5 days of hot water and 1.5 days of cold water, the fastest germination rate, the lowest average germination day, and the highest germination uniformity. This is the best result in most items, and the change temperature immersion treatment of hot and cold baths was superior to the conventional room temperature immersion treatment. Second, the results of birch tree showed that the germination rate was the highest in 1.5 days of hot water and 1.5 days of cold water. The average germination day is 1.5 days of cold water 1.5 days of hot water 1.5 days, but the difference between 1.5 days of hot water and 1.5 days of cold water is 0.01 days. The highest germinated uniformity was found in 1.5 days of cold water and 1.5 days of hot water. As a result, in the case of larch and birch, the seed temperature immersion (1.5 days of hot water, 1.5 days of cold water) treatment is superior to the existing three-day immersion treatment in various analysis methods, and it is expected that productivity and efficiency can be improved at a low cost in a short period of time at the seedling production site through seeds.

• Journal of Korean Clinical Nursing Research
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• v.23 no.1
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• pp.20-29
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• 2017

Purpose: The purpose of this study was to investigate symptoms experienced by patients who reported fever at the emergency room (ER) and to identify any existing cluster of symptom related to fever. Methods: The study used a retrospective and descriptive design with secondary data analysis. Data were abstracted from 665 medical records of patients with fever who visited ER from September 1, 2015 to August 31, 2016 at a tertiary hospital. Results: The most frequently reported symptoms included cold (43.9%), myalgia (24.1%), headache (16.2%), general weakness (15.3%), respiratory symptoms (12.3%), gastrointestinal (GI) symptoms (12.0%), mental change (4.5%), sweating(1.8%), and warmth (0.9%). Analysis of the symptoms related to fever revealed seven symptom clusters; Cluster 1 (n=190) included cold (100%) and myalgia (28.9%); Cluster 2 (n=37), headache (100%) and myalgia (32.4%); Cluster 3 (n=33), GI symptoms (100%), general weakness, headache, and cold; Cluster 4 (n=34), cold (100%), myalgia, headache, and respiratory symptoms; Cluster 5 (n=241), respiratory symptoms (10.8%); Cluster 6 (n=76): myalgia (75.0%) and general weakness, and Cluster 7 (n=54), cold (87.0%), general weakness, and respiratory symptoms. Conclusion: The results of this comprehensive symptom assessment are hoped to be helpful in developing better symptom management for ER patients with fever than before. Further research is warranted to verify the symptom clusters of this study in different clinical settings.

• Korean Journal of Medicinal Crop Science
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• v.23 no.4
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• pp.305-310
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• 2015

This study was conducted to obtain the basic data related to seed characteristics and germination conditions of the Coriandrum sativum L. at different storage condition and temperature. The shape of fruit was oval with light brown color. Fruit was mericarp, biloculate, with one ovule in each locus. The length and width of seed were $1.37{\pm}0.067mm$ and $0.52{\pm}0.039mm$, respectively. Weight of 1,000 seeds was $6.55{\pm}0.15g$. Seeds which were stored at room ($15^{\circ}C$) and cold temperature ($4^{\circ}C$) in vinyl container showed the highest germination rate (93.3%) under the room temperature germination condition. Percentage of germination in cold and freeze temperature was 20% and 0%, respectively. Germination rate of room storage seeds with paper container increased to about 91.3%, however, decreased in cold ($4^{\circ}C$) and freeze storage ($-20^{\circ}C$) with paper container (76.7% and 78.0%, respectively). Germination rate of seed in vinyl stock container was better than that of paper stock container. Germination rate of seeds stored at room temperature for 4 years (2010 - 2013) ranged from 80.0% to 91.3%. Therefore, coriander seeds are expected to be stored at room temperature for increasing the germination rate and keeping a long term.

• Korean journal of food and cookery science
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• v.10 no.4
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• pp.405-411
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• 1994

This study was conducted to know the quality of chou made with flour pastes which were stored at different conditions of quick freezing, slow freezing, cold and room temperature. Also, this study included investigation of the chou properties such as expansion, sensory evaluation, degree of gelatinization, and physical and structural properties of paste were observed. There were not significant differences m diameter, height, volume, appearance, hollow formation, and sensory evaluation between the chou made with the paste stored at freezing condition and chou directly baked after pasting. Quick and slow freezing storages did not significantly affect the properties of chou, and the same results were obtained among the chou made with pastes thawed at room temperature and in microwave ovenrange. The chou of pastes stored at room temperature and in microwave ovenrange. The chou of pastes stored at room temperature and stored in refrigerator showed lowed expansion and value of sensory evaluation than those of frozen pastes. The paste stored at room temperature had the lowest hardness and viscosity compared with the other storage conditions. According to the observation of light microscope. the lipid bodies of the paste of freezing storage smaller those of the room temperature and refrigerator storage. The expantion of chou made with paste stored at room temperature was greatly decreased due to the high coalescence of lipid bodies, and also the paste components such as lipid, starch granule gluten at room temperature had inferior dispersion condition. The general tendency of the degree of gelatinization of chou were low in all treatments of paste. The values were 23.5%~46.0% in freezing, 77.3% in room temperature, 68.7% in directly baked after pasting, and 61.0% in cold storage, respectively. The formation and the taste of chou made with frozen paste were similar to those of chou directly baked pasting.