• KIEAE Journal
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• v.14 no.1
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• pp.23-30
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• 2014

The preferred illumination environment in accordance with the actions taken by the occupants of the rooms in residences differs significantly between different cultures and circumstances in and out of the country. In this regard, the purpose of this study is to evaluate the visual performance of various illumination environments in residential spaces by allowing the participants of the experiments to select the kind of illumination environment they prefer as the occupants of the room. For this purpose, we prepared a mock-up residential space of $6.2m{\times}4.5m{\times}2.5m$, where the experiments for this study were conducted. Then, three illuminance settings (30lx, 100lx, and 150lx) and three color temperature settings (2700k, 4000k, and 6500k) were selected as the properties of the physical environment where the tests were to be conducted. The survey was conducted with 30 study subjects, with whom the level of visual comfort and the lighting adjustment evaluation by different activities were carried out. The level of visual comfort in lighting in a residential context turned to be more influenced by the color temperature and illuminance compared to other factors. Except for the test item, 'comfort,' all test items showed positive reactions when the illuminance was 150lx, which was rather light. In 'comfort,' the test subjects appeared to prefer warm color temperature of 2700k. As we allowed the occupants to adjust the lighting environment in accordance with the conditions of the subjects and the activities they performed, the subjects regarded 150lx - 4000k setting as comfortable, while they preferred 150lx-5400k configuration for working. In case of resting, the subject answered that the configuration of 30lx -2700k setting to be visually comfortable.

• Journal of the Korean Ceramic Society
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• v.36 no.4
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• pp.403-409
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• 1999

The dielectric and pyroelectric properties of $Ba_{0.66}$$Sr_{0.38}$$TiO_{3}$(BST) thin films growtn on Pt/Ti/NON/Si us-ing RF magnetron sputtering have been investigated. With increasing the substrate temperature during de-position of the BST film in the range of 300-$600^{\circ}C$ the dielectric and pyroelectric constants of the film were increased due to improved crystallinity of the film. In addition the dependence of the microstructural and electrical properties of BST films onthe deposition temperature of the bottom Pt electrode was studied. The preferred orientation of the BST films as well as the microstructure of the Pt film was greatly in-fluenced by the deposition temperature of the bottom Pt electrode was studied. The preferred orientation of the BSt films as well as the microstructure of the Pt film was greatly in-fluenced by the deposition temperature of the bottom Pt electrodes. and thus so were the pyrolelectric pro-perties of the BST film. The highest value of pyroelectric coefficient at room temperature obtained in this work was $nCcm^{-2}K^{-1}$ which is much higher than those previously reported on other perovskite fer-roelectric thin films.

• Journal of the Korean Society of Clothing and Textiles
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• v.28 no.8
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• pp.1175-1185
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• 2004

This study evaluated thermo-physiological and subjective properties of improved disposable coveralls for railroad carriage maintenance through climatic chamber trials and a filed study. Subjects wore five kinds of disposable coveralls (Type A: a disposable coverall on the market, Type B: a coverall with an improved hood and size-adjustable design, Type C: a coverall with a portable hood, Type D: a coverall with small holes for ventilation, Type E: a sleeveless coverall, Type F: a separated type of coverall with half sleeves) The air temperature in the climatic chamber was set in 9$^{\circ}C$ and 30$^{\circ}C$ For each condition, subjects simulated the railroad work for 120min. and rectal temperature, skin temperatures, clothing microclimate and subjective sensations were measured. The results of chamber trials showed rectal temperature and clothing microclimate did not display significant differences by clothing type. In 30$^{\circ}C$ air temperature, mean skin temperature was higher in Type E and Type F than in Type A(p＜0.05) but between the improved coveralls(B-F), we could not find any significant difference. In the case of thermal comfort, the most preferred types were Type B and Type C in 9$^{\circ}C$ and Type F in 30$^{\circ}C$. All subjects felt more comfortable in the improved coveralls than in coveralls of the market (Type A). In field study, workers preferred Type B, Type C and Type F to Type A but the most favorite type differed by the specific type of work. Especially, workers were dissatisfied that Type D tore easily due to lots of small holes around the armpits and Type I did not protect workers＇ shoulder and arms from oil contamination. According to the climatic chamber trials and field study, the most effective coveralls were Type B and Type C for winter and Type F for summer.

• Journal of Korea Water Resources Association
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• v.52 no.spc2
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• pp.845-853
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• 2019

The aim of this study is to investigate the factors affecting the habitat characteristics of largemouth bass (Micropterus salmoides), which is one of exotic fishes in Korea. Based on field observation, the laboratory experiments were performed in order to investigate the relationship between water temperature and the habitat characteristics of largemouth bass. It was found that largemouth bass preferred a relatively high water temperature in winter and a low temperature in summer. When the small largemouth bass coexisted with large largemouth bass, the separation of habitats depending on the size of each largemouth bass are observed. In the separated habitat areas, it is also observed that the largemouth bass preferred vicinity of the obstacle such as boulder. From the experiments for preference between water temperature and obstacle, it was observed that a primary consideration in habitat selection was obstacles. It was also observed that when light device was turned on, largemouth bass formed a new habitat.

• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.96.2-96.2
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• 2010

The surface morphology and structural properties of polycrystalline silicon (poly-Si) films made in-situ aluminum induced crystallization at various substrate temperature (300~600) was investigated. Silicon films were deposited by hot-wire chemical vapor deposition (HWCVD), as the catalytic or pyrolytic decomposition of precursor gases SiH4 occurs only on the surface of the heated wire. Aluminum films were deposited by DC magnetron sputtering at room temperature. continuous poly-Si films were achieved at low temperature. from cross-section TEM analyses, It was confirmed that poly-Si above $450^{\circ}C$ was successfully grown on and poly-Si films had (111) preferred orientation. As substrate temperature increases, Si(111)/Si(220) ratio was decreased. The electrical properties of poly-Si film were investigated by Hall effect measurement. Poly-Si film was p-type by Al and resistivity and hall effect mobility was affected by substrate temperature.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.07a
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• pp.1084-1087
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• 2001

The (Sr$\sub$0.85/Ca$\sub$0.15/)TiO$_3$(SCT) thin films are deposited on Pt-coated electrode(Pt/TiN/SiO$_2$/Si) using RF sputtering method. The crystallinity of SCT thin films is increased with increase of substrate temperature in the temperature range of 100[$^{\circ}C$]∼500[$^{\circ}C$]. Also, the crystallinity of SCT thin films are obtained at the substrate temperature above 400[$^{\circ}C$]. SCT thin films had (111) preferred orientation. The dielectric constant changes almost linearly in temperature ranges of-80∼+90[$^{\circ}C$]. The temperature properties of the dielectric loss have a stable value within 0.1. SCT thin films used in this study show the phenomena of dielectric relaxation with the increase of frequency, and the relaxation frequency is observed above 200[kHz].

• Culinary science and hospitality research
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• v.20 no.1
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• pp.89-104
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• 2014

The purpose of this study was to investigate the effects of demographic characteristics such as gender, marital status, age, educational level, job and monthly income on the preferred menu classified by type of food, food material, cooking method, taste and food temperature. A survey was performed from the 5th to 10th of January, 2013 among consumers in such places as coffee shops and subway stations located in Daegu and Gyeongbuk region, and finally 307 data sets were used for analysis. The results of analysis showed that the strongest effects of demographic characteristics were observed in preferred menu classified by type of food(i.e. Korean, Western, Chinese, Japanese, buffet, herbal and instant foods), and the differences by marital status, age, educational level, job were statistically significant. In particular, the married consumers tended to prefer Korean and herbal foods, while the unmarried ones preferred western, Chinese, buffet and instant food. Moreover, the younger ones tended to prefer western, Chinese, buffet and instant foods, while the older ones preferred to eat Korean food. The younger unmarried ones liked beef and pork dishes, while the married ones over their forties tended to prefer vegetable dishes. The consumers less than or equal to their thirties tended to prefer roasted and fried foods compared to ones over their thirties.

• Journal of the Korean Society of Clothing and Textiles
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• v.35 no.12
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• pp.1418-1424
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• 2011

This study proposes the suggested amount of clothing (SAC) and examines the preferred amount of clothing (PAC) for thermal comfort in mild cold conditions. Six male and nine female college students were systematically exposed to mild cold conditions by reducing the amount of clothing (Step I, 1.2clo ${\rightarrow}$ Step II, 1.0clo ${\rightarrow}$ Step III, 0.8clo ${\rightarrow}$ Step IV, 0.7clo). The subjects were then asked to adjust the amount of clothing to attain overall thermal comfort until they maintained thermal comfort for 10 minutes without changing the amount of clothing (Step V). The experiment was carried out in a climatic chamber at $19.5^{\circ}C$, 50%R.H. Body composition was measured and individual cold climate adaptability was surveyed before starting the experiment. Rectal temperature ($T^{re}$), skin temperature ($T_{sk}$), and oxygen consumption ($\dot{V}O_2$) were measured and the overall thermal sensation was voted in each step. PAC was obtained from the garments weight selected by each subject in Step V. SAC was proposed based on the change of oxygen consumption (${\Delta}\dot{V}O_2$). As a result, males showed higher $\bar{T}_{sk}$ and greater $O_2$ than females (p<.01). SAC obtained from $\dot{V}O_2$ were 652.0 (SE 3.9) g/$m^2$ for males and 766.0 (SE 2.5) g/$m^2$ for females and it was significantly different between groups (p<.01). PAC of males and females were 1.6 and 1.5 times heavier than SAC. In conclusion, females were more sensitive to the cold stress and recommended larger amount of clothing than males.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.11 no.11
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• pp.984-989
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• 1998

The ($Sr_{1-x}Ca_x)TiO_3$(SCT) thin films are deposited on Pt-coated electrode($Pt/TiN/SiO_2/Si$) using RF sputtering method with substitutional contents of Ca. The maximum grain of thin films is obtained by substitution of Ca at 15[mol%]. All SCT thin films had (111) preferred orientation. The dielectric constant was increased with increasing the substitutional contents of Ca, while it was decreased if the substitutional contents of Ca exceeded over 15[mol%]. The dielectric constant changes almost linearly in temperature ranges of -80~+90[$^{\circ}C$]. The temperature properties of the dielectric loss have a stable value within 0.02 independent of the substitutional contents of Ca. All SCT thin films used in this study show the phenomena of dielectric relaxation with the increase of frequency, and the relaxation frequency is observed above 200[kHz].

• Journal of the Korean Ceramic Society
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• v.32 no.4
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• pp.419-428
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• 1995

Polycrystalline silicon carbide (SiC) thick films were depostied by low pressure chemical vapor deposition (LPCVD) using CH3SiCl3 (MTS) and H2 gaseous mixture onto isotropic graphite substrate. Effects of deposition variables on the SiC film were investigated. Deposition rate had been found to be surface-reaction controlled below reactor temperature of 120$0^{\circ}C$ and mass-transport controlled over 125$0^{\circ}C$. Apparent activation energy value decreased below 120$0^{\circ}C$ and deposition rate decreased above 125$0^{\circ}C$ by depletion effect of the reactant gas in the direction of flow in a horizontal hot wall reactor. Microstructure of the as-deposited SiC films was strongly influenced by deposition temperature and position. Microstructural change occurred greater in the mass transport controlled region than surface reaction controlled region. The as-deposited SiC layers in this experiment showed stoichiometric composition and there were no polytype except for $\beta$-SiC. The preferred orientation plane of the polycrystalline SiC layers was (220) plane at a high reactant gas concentration in the mass transfer controlled region. As depletion effect of reactant concentration was increased, SiC films preferentially grow as (111) plane.