• 자원ㆍ환경경제연구
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• 제10권2호
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• pp.217-234
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• 2001

The use of district heating is expanding very rapidly in Korea. High population densities and the relatively cold winters make district heating an economically attractive option. About 8 percent of Korean houses are already using district heating and the government is seeking to aggressively expand this number. It has set a target of 15 percent of the residential heat market to be met by district heating in the year 2001. The main purpose of this paper is to analyze the consumption behavior of households using district heating. By pooling time-series and cross-sectional data for 12 apartment complexes in Seoul area, a single demand function is estimated and used to forecast the amounts of heat demanded by the individual households. The results shows that the level of consumption varies among households, depending on the non-economic factors such as the installation of individual metering equipment and the volume of apartment building. When individual metering equipment is installed, the level of annual heat consumption per household declines, on average, about 22.1 Mcal per square meters, which is equivalent to 834 won per square meter in terms of heating expenditures. In case that the apartment building was built in more than 6 stories, annual consumption level reduces additionally about 17.3 Mcal per square meters and, thus, save the expenditures by 649 Won per square meters, compared to the opposite case.

• 동의생리병리학회지
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• 제27권4호
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• pp.343-349
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• 2013

This article is a study on to which categories of modern diseases blood deficiency pattern types are assigned by reference to modern clinical papers. Clinical papers were searched in China National Knowledge Infrastructure(CNKI) from 1994 to 2013. Results are as follows. First, diverse diseases classified in qi-blood depletion pattern and pattern of blood deficiency and wind-dryness are reported and pattern types designated by the name of viscera are the minority. Second, among pattern types in Korean Standard Classification of Diseases(KCD), diseases classified in heart blood deficiency pattern, liver blood deficiency pattern and heart-liver blood deficiency pattern are a few. Third, the level of designation by the combined patterns such as qi deficiency, fluid deficiency, yin deficiency, kidney deficiency, essence deficiency, wind-cold, cold-dampness, dampness-heat, liver hyperactivity, liver depression and static blood is more specific than KCD, which makes pattern types more useful to clinical application. The detailed relation between modern diseases and pattern types can be an another topic.

• 설비공학논문집
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• 제17권7호
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• pp.649-658
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• 2005

Flow condensation heat transfer coefficients (HTCs) of R22, R410, Propane (R290) were measured inside a horizontal 9 hole aluminum multi-channel flat tube. The main test section in the refrigerant loop was made of a 0.53m long multi-channel flat tube of hydraulic diameter of 1.4 mm. Refrigerant was cooled by passing cold water through an annulus surrounding the test section. Data were obtained in qualities of $0.1\~0.9$ at mass flux of $200\~400kg/m^2s$ and heat flux of $7.3\~7.7kW/m^2$ at the saturation temperature of $40^{\circ}C$. All popular heat transfer correlations in single-phase subcooled liquid flow and flow condensation originally developed for large single tubes predicted the present data of the multi channel flat tube within $25\%$ deviation when effective heat transfer area was used in determining experimental data. This suggests that there is little change in flow characteristics and patterns when the tube diameter is reduced down to 1.4 mm diameter range. Hence, a modified correlation based on the present data was proposed which could be applied to small diameter tubes with effective heat transfer area. The correlation showed a mean deviation of less than $20\%$ for all data.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2005년도 동계학술발표대회 논문집
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• pp.249-255
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• 2005

Flow condensation heat transfer coefficients(HTCs) of R22, R4IO, Propane(R290) were measured inside a horizontal 9 hole aluminum multi-channel flat tube. The main test section in the refrigerant loop was made of a 0.53 m long multi-channel flat tube of hydraulic diameter of 1.4 mm. Refrigerant was cooled by passing cold water through an annulus surrounding the test section. Data were obtained in qualities of 0.1 ${\sim}$ 0.9 at mass flux of $200{\sim}400$ $kg/m^2s$ and heat flux of $7.3{\sim}7.7$ $kW/m^2$ at the saturation temperature of $4^{\circ}C$. All popular heat transfer correlations in single-phase subcooled liquid flow and flow condensation originally developed for large single tubes predicted the present data of the multi channel flat tube within 25% deviation when effective heat transfer area was used in determining experimental data. This suggests that there is little change in flow characteristics and patterns when the tube diameter is reduced down to 1.4 mm diameter range. Hence, a modified correlation based on the present data was proposed which could be applied to small diameter tubes with effective heat transfer area. The correlation showed a mean deviation of less than 20% for all data.

• Fisheries and Aquatic Sciences
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• 제26권11호
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• pp.639-648
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• 2023

The sea surface temperature (SST) and ocean heat content in the Korea Waters are gradually increased. Especially the increasing trend of annual mean SST in the Korea Water is higher about 2.6 times than the global mean during past 55 years (1968-2022). Before 2010s, the increasing trend of SST was led by winter season in the Korea Waters. However, this pattern was clearly changed after 2010s. The increasing trend of SST during summer is higher about 3.9 times than during winter after 2010s. We examine the long-term variations of several ocean and climate factors to understand the reasons for the long-term pattern changes of SST between summer and winter in recent. Tsushima warm current was significantly strengthened in summer compare to winter during past 33 years (1986-2018). The long-term patterns of Siberian High and East Asian Winter Monsoon were definitely changed before and after early- or mid-2000s. The intensities of those two climate factors was changed to the increasing trend or weakened decreasing trend from the distinctive decreasing trend. In addition, the extreme weather condition like the heatwave days and cold spell days in the Korea significantly increased since mid- or late-2000s. From these results, we can consider that the occurrences of frequent and intensified marine heatwaves during summer and marine cold spells during winter in the Korea Waters might be related with the long-term pattern change of SST, which should be caused by the long-term change of climate factors and advection heat, in a few decade.

• 한국의상디자인학회지
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• 제25권3호
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• pp.31-39
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• 2023

This paper aimed to provide the basic data on consumers' awareness, behavioral patterns, and purchase methods for pet fashion(dog clothes). Research was conducted in April 2023 among 183 college students from universities in the Gyeonggi-do region. The analysis results are presented below. When asked if they think clothes are a daily necessity for dogs, 74.3% recognized clothes as a daily necessity for dogs. The biggest purpose of clothing for dogs was 'physical health (prevention of cold/heat, etc.)' with 60.1%. 96.7% of the respondents were very positive about the development prospects for the pet fashion industry. 46.4% of the subjects were currently living with a dog, and 30.6% of the subjects have lived with a dog for 'less than 1-3 years'. 93.0% of college students who live with a dog own dog clothes. As for the dog's clothing style, T-shirt styles without a slit were the most common at 33.6%. 81.0% of companion dog owners were found to dress their dogs when going out, and the most common reason was 'physical health (prevention of cold/heat, etc.)' at 76.6%. When purchasing dog clothes, 72.2% of the subjects considered 'fitting with the dog/convenience', and 27.8% were 'focusing on the companion's taste'. As for how to purchase dog clothes, 39.2% chose 'store visits and online purchases', 34.2% chose 'store visits and purchases', and 26.6% chose 'online purchases'. As for the most considered part when purchasing clothes for dogs, 51.9% identified 'design' and 39.2% identified 'material'. 80.7% of respondents said they would increase the purchase of dog clothes in the future.

• 대한한방내과학회지
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• 제38권6호
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• pp.955-970
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• 2017

Objectives: The aim of this observational study was to identify and analyze the patterns to compare the characteristics of asthma patients. Methods: The subjects were 40 asthma patients who had satisfied the inclusion and exclusion criteria. They were divided into deficiency syndrome and excess syndrome groups, and cold syndrome and heat syndrome groups. Their quality of life was measured by the quality of life questionnaire for adult Korean asthmatics (QLQAKA) and VAS. Heart rate variability (HRV) was measured, and the degree of obesity was evaluated by body mass index (BMI). Hematological, biochemical, and immunoglobulin (Ig) E laboratory tests were included. Results: Based on pattern identification, the 40 asthma patients could be divided into two categories of groups: 1) the deficiency syndrome (N=18) and the excess syndrome (N=22) groups: 2) the cold syndrome (N=35) and the heat syndrome (N=5) groups. The mean value of HF differed significantly between the deficiency and excess syndrome groups. The mean value of IgE in blood tests of asthmatics was greater than four times the reference value. For BMI, the subjects were classified into three groups: normal weight (N=12), overweight (N=12), and obese (N=16). Conclusions: Development of a more accurate asthma-specific pattern identification tool could play a crucial role in asthma control. In addition, good control of asthma can improve the quality of life. Obesity is one of the factors associated with asthma exacerbation.

• 대한한의진단학회지
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• 제12권2호
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• pp.74-83
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• 2008

Background and purpose : Health is characterized by variability, and the loss of variability is associated with aging and disease. Normal healthy respiratory patterns are characterized by breath to breath variability. Cold-Heat scores are quantified indices in Korean Medicine. The aim of this study is to analyze relations between 9 respiratory indices (including breath to breath variability) and HRV(heart rate variability). Method : Respiratory data were measured during a period of 15 minutes and transferred to text file. We calculated 9 respiratory parameters using MATLAB 7.1. Afterwards we did correlation analysis of the 9 respiratory indices and HRV. Results and conclusion : Respiratory variability showed significant correlation with HRV.

• 소성∙가공
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• 제5권3호
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• pp.239-255
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• 1996

A new forming technology has been developed to fabricate near-net shape products using light metal. A semi-solid forming technology has some advantages compared with the conventional forming processes such as die casting squeeze casting and hot/cold forging. In this study the numerical analysis of semi-solid filling for a straight die shape and orifice die shape in gate pattern is studied on semi-solid materials(SSM) of solid fraction fs =30% in A356 aluminum alloy. The finite difference program of Navier-Stokes equation coupled with heat transfer and solidification has been developed to predict a filling pattern and the temperature distribution of SSM. The programdeveloped in this study gives die filling patterns of SSM and final solidifica-tion region.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2006년도 춘계학술대회 논문집
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• pp.425-428
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• 2006

A semi-solid forming technology has some advantages compared with conventional forming processes such as die casting, squeeze casting and hot/cold forging. In this study, the numerical analysis of semi-solid filling has been studied with solid fraction fs = 30% of A356 aluminum alloys. The finite difference program of two-phase flow model of Navier Stokes' equation coupled with heat transfer and solidification has been developed to predict a filling pattern, liquid segregation and temperature distribution of semi-solid metals. It gives die filling patterns and final solidification area. It can predict mechanical properties of semi-solid forming processes.