• 한국자동차공학회논문집
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• 제23권4호
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• pp.428-435
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• 2015

This paper presents the experimental study of cabin thermal comfort using a cold storage heat exchanger in a vehicle air-conditioning system. Recent vehicle-applied ISG functions for fuel economy and emission, but when vehicles stop, compressors in the air-conditioning system stop, and the cabin temperature sharply increases, making passengers feel thermal discomfort. This study conducts thermal comfort evaluation in the vehicle, which is applied to a cold storage system for the climate control wind tunnel test and the vehicle fleet road test with various airflow volume rates and ambient temperatures blowing to the cold storage heat exchanger. The experimental results, in the cold storage system, air discharge temperature is $3.1-4.2^{\circ}C$ lower than current air-conditioning system when the compressor stops and provides cold air for at least 38 extra seconds. In addition, the blowing airflow volume to the cold storage heat exchanger with various ambient temperature was examined for the control logic of the cold storage system, and in the results, the airflow volume rate is dominant over the outside temperature. For this study, a cold storage system is economically useful to keep the cabin at a thermally comfortable level during the short period when the engine stops in ISG vehicles.

• 대한한의진단학회지
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• 제9권2호
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• pp.145-151
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• 2005

Background and purpose: The cold-heat patternization is one of the most frequently use for diagnostic method in oriental medicine. But it is still an unclear scientific mechanism and the objective index. the aim of this study is to search the objective index of the cold-heat patternization, comparing with ordinary health test. Method: The study group comprised 101 Korean, male:female ratio 51:50, with a mean age of 49.74 years. The results of the questionnaires for cold-heat patternization were compared with the western health test that it consist of height, weight, muscle mass, body fat, WBC, Hb, ALT, AST, TG, Total cholesterol, glucose, HDL-cholesterol, free-T4 and TSH, measured in the health promotion center of the hospital of Chungnam university Result: The cold patternization were significantly higher in the women than the man. The somothing of the questionmaires for the heat patternization were positive correlated with TG, TSH, glucose, Hb, free T4, weight, musle mass(p<0.05). But there were no correlation in the gross. The somothing of the questionnaires for the cold patternization were negative correlated with the weight, musle mass, body fat, glucose, Hb and ALT(p<0.05), Especially there were strong negative correlation with the weight and muscle mass(p<0,01). Conclusion: The present study shows there is no definitive index for the cold-heat patternization in the ordinary health test. But the weight and muscle mass can be useful index of the cold patternization.

• 동의생리병리학회지
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• 제31권2호
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• pp.145-152
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• 2017

The purpose of this study was to investigate the clinical research of Cold-Heat of pattern identification(PI) focused on quantitative indicators for general people in Korea, through the review of OASIS, KISS, DBpia, NDSL database. Ten clinical researches were analyzed in this study. These research gradually started from 2004 to 2009 but there was no research after 2010. Diagnosis of Cold-Heat PI all was done through a questionnaire, 7 or most researches had not used the intervention methods. Quantitative indicators related to the Cold-Heat PI mentioned in the selected 10 researches are seven, these indicators include heart rate variability(HRV), electroencephalogram, Yangdorak, respiratory index, electrogastrography, acoustic analysis index, western health test index. Related to the HRV were 3 researches, but correlation of significant indicators was a few levels(R=0.026-0.090). So far, studies regarding at the quantitative indicators of the prior the Cold-Heat PI were few, and the results of the study showed that low statistical precision, a lack of biological basis. Refer to the current state, in the future, we expect that research of quantitative indicators of scientific evidence-based through calculated and precise research concerning Cold-Heat PI be regarded as important in Korean Medicine.

• 대한한방내과학회지
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• 제33권2호
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• pp.209-221
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• 2012

Objectives : The aim of this study was to investigate the relationship between the autonomic nervous system and the cold-heat pattern in patients with chronic constipation. Methods : Subjects with chronic constipation (n=30) and without chronic constipation (n=20) were recruited, interviewed and measured for heart rate variability (HRV). Chronic constipation was defined as functional constipation and Irritable Bowel Syndrome (IBS) with constipation based on Rome III criteria. We surveyed patients' general characteristics, categorized by cold-heat pattern, and took measurement of HRV for 5 minutes. Analysis was conducted among these three indices. Results : Women accounted for most of the subjects with chronic constipation (96.7%). In groups with or without constipation, the number of cold patterns was more than of heat patterns. The mean heart rate of subjects without chronic constipation was significantly higher than that of subjects with chronic constipation. No other statistical significance was noted among indices of HRV and cold-heat pattern. Conclusions : Through this study, there were few relationships between autonomic nervous system measured by HRV and cold-heat pattern in chronic constipation.

• 한국세라믹학회지
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• 제53권1호
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• pp.93-98
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• 2016

Cold plasma and heat treatment were selected as technologies to reduce unburned carbon in fly ash to less than 1.0%. Both cold plasma and heat treatment made it possible to eliminate unburned carbon to less than 1.0%. In the case of fly ash, which almost entirely eliminated unburned carbon with an ignition loss of 0.5%, heat treatment caused adhesion among particles and the BET specific surface area rapidly decreased as the mean particle size increased. On the other hand, with cold plasma, unburned carbon elimination caused the BET specific surface area to decrease and, as no adhesion occurred among particles, the mean particle size became small. Also, cold plasma treatment allowed small spherical particles confined within the unburned carbon particles to be released with the elimination of the unburned carbon frame, so that the quantity of fine particles had a tendency to slightly increase.

• 동의신경정신과학회지
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• 제26권3호
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• pp.283-292
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• 2015

Objectives: The study aimed to test the validity and reliability of the questionnaire for cold-heat & deficiency-excess pattern identification of dementia and establish a new version of the questionnaire. Methods: Mean, standard deviation, skewness, internal consistency, correlation and t-test of the 26 items derived from previous study was analyzed in 20 dementia patients. The items with Cronbach-${\alpha}$ coefficient below 0.7 were modified. Thus, we established a new version of the questionnaire consisting of 20 items. Results: Cronbach-${\alpha}$ of each cold, heat, deficiency and excess questionnaire was 0.662, -0.229, 0.722 and 0.778, respectively. The correlation coefficient between cold, heat, deficiency and excess was less than 0.4 and correlation coefficient between dementia and cold, deficiency was 0.518. On t-test, the t-value of cold, deficiency and dementia was -2.196. Conclusions: The results indicated that cold-heat, deficiency-excess questionnaires showed satisfactory discriminant validity. In addition, there was correlation between dementia and cold, deficiency. Finally, we established a new version of the questionnaire for cold-heat, deficiency-excess pattern identification that consisted of 20 items.

• 한국수소및신에너지학회논문집
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• 제31권3호
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• pp.302-306
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• 2020

In this study, computer simulation works using PRO/II with PROVISION V10.2 have been performed for a cascade refrigeration cycle using methane, ethylene and propane as refrigerants. LNG cold heat was also utilized in order to save the compression powers for the ethylene and propane refrigeration cycles. It was concluded that about 77% of compression power can be saved by using LNG cold heat through the exchanging heat with refrigerants. We could also know that the cold heat price contained in 1 ton of LNG is 16,155 won.

• 한국수소및신에너지학회논문집
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• 제31권2호
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• pp.259-264
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• 2020

In this study, comparison study has been performed between two-stage compression and a vapor-recompression refrigeration cycle and a liquefaction using LNG cold heat. When using a first method using two-stage compression and a refrigeration cycle, at least three compressors are required, however when using LNG cold heat, no compressor is required since carbon dioxide can be pumped after condensing with the heat exchange with -160℃ of LNG. Through this study, we can save more than one hundred million KRW annually by using LNG cold heat instead of using gas compression and refrigeration cycle.

• 한국초전도ㆍ저온공학회논문지
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• 제22권4호
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• pp.45-50
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• 2020

In this research, the variation of round-trip efficiency in a liquid air energy storage system (LAES) is calculated and an optimal configuration is found. The multiple stages of cold energy storage are simulated with several materials that process latent heat at different temperature ranges. The effectiveness in the charging and discharging processes of LAES is newly defined, and its relationship with the round-trip efficiency is examined. According to defined correlation, the effectiveness of the discharging process significantly affects the overall system performance. The round-trip efficiency is calculated for the combined cold energy storage materials of aqueous dimethyl sulfoxide (DMSO) solution, ethanol, and pentane theoretically. The performance of LAES varies depending on the freezing point of the cold storage materials. In particular, when the LAES uses several cold storage materials, those materials whose freezing points are close to room temperature and liquid air temperature should be included in the cold storage materials. In this paper, it is assumed that only latent heat is used for cold energy storage, but for more realistic analyzes, the additional consideration of the transient thermal situation to utilize sensible heat is required. In the case of such a dynamic system, since there is certainly more increased heat capacity of the entire storage system, the volume of the cold energy storage system will be greatly reduced.

• 한국건축시공학회지
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• 제13권1호
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• pp.38-47
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• 2013

When building with concrete in cold weather, an insulation method of heat curing must be determined, and a holistic curing plan that considers the characteristics of structures, the heat loss coefficient of a curing sheet, the joint condition of the curing materials and the quantity of heat produced by a heating apparatus is an essential prerequisite for protection against early frost damage. But on a number of national construction sites, there have been serious problems in cold weather concreting due to the unreliability of the information obtained from practical experience. In the construction field in Japan, there is a specification for heat curing prepared by Japanese Architectural Society, which provides an equation for calculating heat quantity. It is also necessary to adopt a detailed specification for a standard heat curing method that is applicable to all national construction sites. In this study, the effect of bubble sheets on the economic feasibility of cold weather concrete is investigated through a comparison with the blue sheets commonly prescribed in national construction sites. In conclusion, this study found that bubble sheets had the effect of reducing the cost of curing materials and the fuel cost consumed by a heating apparatus, compared to the use of blue sheets.