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Physiological Responses and Subjective Sensations of Human Wearing Soccer Wear of Different Materials and Designs (축구복 소재와 디자인이 인체생리반응과 주관적 감각에 미치는 영향)

  • Choi Jeong-Wha;Kim So-Young;Jeon Tae-Won
    • Journal of the Korean Society of Clothing and Textiles
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    • v.29 no.1 s.139
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    • pp.35-45
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    • 2005
  • The purpose of this study was to evaluate thermal properties of soccer wear with different materials and designs. As a beginning step, the questionnaire survey about the actual condition of soccer wears was conducted. with the results of the questinnaire, two soccer wears with new material and design that were improved in tactile sensations, absorption and ventilation were developed. We evaluated thermal and subjective responses of subjects wearing Korea national soccer team uniform in 1998 World Cup (Uniform 98), soccer wear with new material and same design(New II) and with new material and new design(New I). New I was made with mesh in armhole for improving ventilation. Rectal temperature, skin temperature, clothing microclimate, and heart rate were measured in climatic chamber test(twelve times) and field test(eighteen times). The results were as follows. 1. As the results of the climatic chamber test, rectal temperature was lower in New I and New II than Uniform98, and mean skin temperature was lower in New I than Uniform 98 and New II. Heart rate was lower in New I than New II, and total body weight loss and local sweating were not significantly different by soccer wears. 2. As the results of the field test, rectal temperature was lower in New I than Uniform98 and New II. Mean skin temperature was lower in New II than Uniform98 and New I. Clothing microclimate temperature was lower in New II than Uniform98 and New 1, and clothing microclimate humidity was lower in New I, New II than Uniform 98. Heart rate was lower in New I than Uniform 98, New II and total body weight loss and local sweating were lower in New I, New II than Uniform 98. In conclusion, New I using new design using mesh in armhole and new material using sweat absorbent finishing was excellent from the point of view of physical responses, ventilation and sweat absorption.

Effect of Austenitizing Temperature and Cooling Rate on Microstructure and Hardness of Low-carbon SCM415 Steel (오스테나이타이징 온도와 냉각 속도가 SCM415 저탄소강의 미세조직과 경도에 미치는 영향)

  • Lee, J.U.;Lee, G.M.;Cha, J.W.;Park, S.H.
    • Transactions of Materials Processing
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    • v.31 no.4
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    • pp.207-213
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    • 2022
  • In this study, variations in the microstructure and hardness of a low-carbon SCM415 steel with austenitizing temperature and cooling rate are investigated. When the austenitizing temperature is lower than the A1 temperature (738.8 ℃) of the SCM415 steel, the microstructures of both the air-cooled and water-cooled specimens consist of ferrite and pearlite, which are similar to the microstructure of the initial specimen. When heat treatment is conducted at temperatures ranging from the A1 temperature to the A3 temperature (822.4 ℃), the microstructure of the specimen changes depending on the temperature and cooling rate. The specimens air- and water-cooled from 750 ℃ consist of ferrite and pearlite, whereas the specimen water-cooled from 800 ℃ consists of ferrite and martensite. At a temperature higher than the A3 temperature, the air-cooled specimens consist of ferrite and pearlite, whereas the water-cooled specimens consist of martensite. At 650 ℃ and 700 ℃, which are lower than the A1 temperature, the hardness decreases irrespective of the cooling rate due to the ferrite coarsening and pearlite spheroidization. At 750 ℃ or higher, the air-cooled specimens have smaller grain sizes than the initial specimen, but they have lower hardness than the initial specimen owing to the increased interlamellar spacing of pearlite. At 800 ℃ or higher, martensitic transformation occurs during water cooling, which results in a significant increase in hardness. The specimens water-cooled from 850 ℃ and 950 ℃ have a complete martensite structure, and the specimen water-cooled from 850 ℃ has a higher hardness than that water-cooled from 950 ℃ because of the smaller size of prior austenite grains.

A Study of the Influence of Condensing Water Temperature on Low Temperature Geothermal Power Generation (응축수온도가 저온지열발전 성능에 미치는 영향 연구)

  • Kim, Jin-Sang;Lee, Chung-Kook
    • Journal of the Korean Society for Geothermal and Hydrothermal Energy
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    • v.3 no.2
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    • pp.17-23
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    • 2007
  • Geothermal energy is used in various forms, such as power generation, direct use, and geothermal heat pumps. High temperature geothermal energy sources have been used for power generation for more than a century. Recent technical advances in power generation equipments make relatively low temperature geothermal energy to be available for power generation. In these applications, lower temperature geothermal energy source makes smaller difference between condensing water temperature and it. Various condensing water temperatures were investigated in analyzing its influence on power generation performance. Condensing water temperature of organic Rankine cycle imposed greater influence on power generation and its performance in lower temperature geothermal power generation.

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Studies on The Flow Properties of Semi-Solid Dosage Forms (II) : Temperature-Dependent Flow Behavior of Vaseline (반고형제제의 유동특성에 관한 연구 (제2보) : 바셀린의 온도의존성 유동거동)

  • Kim, Jeong-Hwa;Song, Ki-Won;Jang, Gap-Shik;Lee, Jang-Oo;Lee, Chi-Ho
    • YAKHAK HOEJI
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    • v.41 no.1
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    • pp.38-47
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    • 1997
  • Using a concentric cylinder type, rheometer. the steady shear flow properties of vaseline were measured over the temperature range of 20~70${\circ}$C. In this paper, the shea rate and temperature dependencies of its flow behavior were investigated and the validity of some flow models was examined. In addition, the flow characteristics over a wide temperature range were quantitatively evaluated by calculating the various material parameters. Main findings obtained from this study can be summarized as follows: (1) At relatively lower temperature range, vaseline is a plastic fluid with a yield stress and its flow behavior shows shear-thinning characteristics. (2) As the temperature increases, the value of a yield stress and the degree of shear-thinning become smaller, consequently, the Newtonian flow behavior occurs at a lower shear rate range. (3) At temperature range lower than 45${\circ}$C, the flow behavior shows much stronger temperature dependence, and a larger activation energy is needed for flow. (4) The Herschel-Bulkley model is the most effective one g$^3$ to predict the flow behavior of vaseline having a yield stress. The validity of the Bingham and Casson models becomes more available with increasing temperature. The flow behavior of vaseline at temperature range higher than 45${\circ}$C can be perfectly described by the Newton model.

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A Study on Women's Body Type and Body Temperature in Relation to Gynecologic Disorders and Dysmenorrhea (부인과질환, 월경통과 여성 체형 및 체온의 상관성 연구)

  • Choi, Seok-Young;Ahn, Ji-Yoon;Lee, Mi-Joo;Lee, Jin-Moo;Jang, Jun-Bock;Lee, Kyung-Sub;Lee, Chang-Hoon
    • The Journal of Korean Obstetrics and Gynecology
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    • v.25 no.4
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    • pp.81-93
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    • 2012
  • Objectives: A women's body type or body temperature is often thought to be associated with gynecologic disorders or dysmenorrhea. The purpose of this study is to analyse the characteristics of body type and body temperature in relation to gynecologic disorders and dysmenorrhea. Methods: We studied 40 patients visiting Kangnam Kyung-hee Medical Center from Jan. 1st, 2010 to March 31st, 2012. Body type and body temperature were compared between Gynecologic disorder group and non-Gynecologic disorder group. Body type and body temperature were compared again between Dysmenorrhea group and non-Dysmenorrhea group. SPSS 18.0 for Windows was used to analyse the data. Results: There was no statistically significance difference in body type and body temperature between Gynecologic disorder group and non-Gynecologic disorder group. Dysmenorrhea group had more developed lower body and greater temperature difference between lower abdomen and foot compared to non-Dysmenorrhea group. Conclusions: The results suggest that women with developed lower body and greater temperature difference between abdomen and lower extremity are more prone to dysmenorrhea.

Physiological Responses of Wearing Industrial Gaiters in a Hot Environment (더운 환경에서 산업용 각반 착용 시 인체생리반응)

  • Choi, Jeong-Wha;Park, Joon-Hee
    • Journal of the Korean Society of Clothing and Textiles
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    • v.32 no.7
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    • pp.1129-1136
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    • 2008
  • The gaiter is one of the personal protective equipments worn in various industrial sites. This study was performed on humans to investigate the physiological strain of wearing gaiters and to compare control gaiters that are currently on the market and new gaiters that are developed for alleviating heat stress. Experiments were conducted in a climatic chamber of WBGT $30.0\pm0.7^{\circ}C$ under five differed experimental conditions: None, Control A, Control B, New A, New B. The results were as follows. The temperature inside gaiters was significantly lower in both New A and New B than in both Control A and Control B and the difference between news and controls was 1$^{\circ}C$ (p<.01). The humidity inside gaiters in both New A and New B were higher than that in Control A, and lower than that in Control B (p<.01). The outermost surface temperature of the gaiter was the lowest in None and it increased in the following order: New B < New A < Control A < Control B. Mean skin temperature was higher by 0.14$^{\circ}C$ in wearing gaiters than in no gaiters. Skin temperatures in lower body were lower in Control than in New and skin temperature in upper body were higher in Control than in New (p<.01). Local sweat rate, total weight loss and subjective sensations did not show a significant difference according to the gaiters. It was concluded that wearing gaiters affected distribution of skin temperature and local sweat rate.

Characteristics of Water Temperature Inversion Observed in a Region West of Jeju Island in April 2015 (2015년 4월에 제주 서부해역에서 발생한 수온역전층 특성)

  • Kim, Seong Hyeon
    • Ocean and Polar Research
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    • v.42 no.2
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    • pp.97-113
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    • 2020
  • In-situ observations were carried out in April 2015 to investigate the occurrence of water temperature inversion in a region west of Jeju Island. Analysis of in-situ in the western part of Jeju island showed that cold water moved to the southeast from the surface to the middle layer and warm water moved from the middle to the lower layer of the northwest direction. The water temperature inversion occurred at 84 stations (63.1%) out of 133 stations. At the boundary of the water temperature inversion layer, it was formed in the middle layer and disappeared. In the strongly appearing, it started from the middle layer to the lower layer. The shape of the water temperature inversion layer was different. As a result of horizontal water temperature slope analysis of the water temperature inversion zone, maximum 0.23℃/km was obtained and the mean was 0.06℃/km. The role of water temperature inversion as an indicator to determine the formation of water front. As a result of the water mass analysis, Jeju Warm Current Water and Tsushima Warm Current Water of high temperature and high salt intruded from the middle to the bottom. In the middle layer occurred as the Yellow Sea Cold Water of low water temperature and low salinity expanded.

Actual operation characteristics to evaluate the performance of heat pump outdoor unit in the constant temperature chamber (항온챔버에서 히트펌프 실외기의 성능을 평가하는 실제 운전)

  • Jong-Ryeol Kim
    • Journal of the Institute of Convergence Signal Processing
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    • v.23 no.3
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    • pp.123-128
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    • 2022
  • A lot of research is being done to develop a high-efficiency heat pump to save energy, and research to reduce or eliminate the phenomenon of frost occurring in the outdoor unit coil is also being conducted at the same time. In order to conduct a study that does not cause frost on the outdoor unit of the heat pump regardless of the season, a constant temperature chamber like a general room that can be tested under the same conditions as in the natural state was built. The experiment was conducted by providing an environment similar to the natural state to the outdoor unit of the heat pump installed in the constant temperature chamber. As a result, the lower the outdoor temperature, the lower the efficiency of the heat pump. It wat confirmed that the lower the value, the longer it is.

Evaluation of Thermal Environment of External Space following the Fence Demolition Campaign in Detached Housing Area (담장허물기로 인한 주택지 외부공간의 열환경 평가)

  • Ryu, Ji-Won;Jung, Eung-Ho;Shimizu, Aki;Oh, Sang-Hak;Hoyano, Akira
    • Journal of the Korean housing association
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    • v.23 no.1
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    • pp.19-26
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    • 2012
  • This study examines how fence demolition may change the thermal environments of external spaces of houses and suggests what factors need to be considered when a fence is demolished. The results of the research are summarized as follows. In terms of the surface temperature, there was no significant difference in all time plots after the removal of all materials. However, applying greening methods (changing the surface materials, planting trees, and building a green roof following fence demolition) could lower the surface temperatures, calling for proper plans for various greening methods. The MRT results indicates that walls block solar radiation and provide shade, reducing radiant heat from roads and surrounding structures during the daytime when solar radiation directly effects surface temperatures. Also, the application of greening methods such as planting vegetation and trees could have shading and evapotranspiration effects, leading to a lower temperature distribution. The HIP results were similar to the MRT results. They indicated that walls block solar radiation within the residential sections and provide shade, resulting in a lower temperature distribution during the daytime. However, areas where greening methods such as a green roof or tree planting were applied showed $1{\sim}2^{\circ}C$ difference in temperature distribution.

Comparison of Inguinal, Rectal, Axillary,and Tympanic Temperature in Newborns (신생아의 서혜, 직장, 액와, 고막 체온 측정 비교)

  • Koo, Hyun-Young;Son, Jung-Tae
    • Child Health Nursing Research
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    • v.11 no.2
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    • pp.203-210
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    • 2005
  • Purpose: In order to identify the usability of inguinal temperature in a neonatal unit, this study was done to compare inguinal temperature of newborns with rectal, axillary, and tympanic temperatures. Method: Fifty-one normal newborns admitted to the nursery of a university affiliated hospital participated in the study. Tympanic temperatures were taken with a tympanic thermometer. Inguinal, rectal, and axillary temperatures were taken with glass mercury thermometers, and were recorded every 1 minute until the reading remained constant for 2 times. The data were analyzed using the SPSS program. Result: The measurement time for inguinal temperatures in newborns was significantly longer than that for rectal temperatures, but was shorter than that for axillary temperatures. The mean temperature for the newborn's inguinal site was lower than for rectal, axillary, and tympanic temperatures (the lower side), but wasn't different from tympanic temperature (the upper side). The inguinal temperature was significantly correlated with rectal, axillary, and tympanic temperature. The inguinal temperature was not different according to general characteristics of the newborn. Conclusion: These findings indicate that measurement of inguinal temperature is a useful alternative to rectal temperature.

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