• Title/Summary/Keyword: Hot-Cold

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Thermal Sensation in Winter Classroom and Cold Climate Adaptability of Junior High School Students (남녀 중학생의 겨울철 교실 내 한서감과 기후적응성)

  • Cho, Areum;Shim, Huensup
    • Fashion & Textile Research Journal
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    • v.20 no.6
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    • pp.744-751
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    • 2018
  • This study aimed to provide the information on the thermal sensation and the amount of clothing worn of junior high school students in winter classroom the relation with their climate adaptability. Total usable questionnaires were obtained from 467 male and female students. The questionnaire included general characteristics, physical characteristics, self awareness of body shape, climate adaptability and subjective thermal sensation in winter classroom. The data were analyzed using SPSS Statistics 18.0 for frequency analysis, factor analysis, chi-square analysis, t-test and correlation analysis. The results were as follows. The average body type based on BMI was normal($20.1kg/m^2$ ). Females perceived their body type as thinner than males. They wore more (8.67 garment items compared to 8.14 for males). Only about 25% of students voted the thermal sensation to neutral(47% cool~very cold, 28% warm~very hot). Females were more sensitive to the cold, perceived less healthy, and wore more garments in the cold. Students felt colder in winter classroom when their cold adaptability was lower and they actively adjusted thermal insulation against the cold. It is recommended to suggest the guidelines for the proper indoor temperature and for the wear behavior in classroom in the perspectives of increasing the learning efficiency and improving the students' climate adaptability.

Effectiveness Validation on Cold Multi-Stage Forging of Aluminum Inner Tie Rod Socket (알루미늄 이너 타이로드 소켓의 냉간다단단조 유효성 검증)

  • Park, Jae-Wook;Choi, Jong-Won;Jeong, Enn-Eun;Yoon, Il-Chae;Kang, Myungchang
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.21 no.1
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    • pp.49-55
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    • 2022
  • Recently, the automobile industry has continued to demand lighter materials owing to international environmental regulations and increased convenience. To address this demand, aluminum parts have increased in popularity and are mainly developed and produced through hot forging and cold pressing. However, because this method has low yield and low production efficiency, a new manufacturing method is desirable. In this study, the water capacity efficiency of an aluminum inner tie rod socket was investigated using cold forging that provided a high yield and excellent production efficiency. Mechanical properties were derived through tensile testing of 6110A aluminum materials, and critical fracture factor and process analysis based on experimental data were carried out. The optimized process was applied as a prototype using cold multi-stage forging, and based on the derived results, the formability, productivity, and material efficiency of aluminum inner tie rod socket parts using this cold forging process was verified.

Studies on Plywood Treated Fire-Retardant - III. The Fire-Retardant Degree of Monoammonium Phosphate Treated Plywood (합판(合板)의 내화처리(耐火處理)에 관(關)한 연구(硏究) - III. 제1인산(第一燐酸)암모늄처리합판(處理合板)의 내화도(耐火度))

  • Kim, Jong-Man
    • Journal of the Korean Wood Science and Technology
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    • v.14 no.4
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    • pp.21-28
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    • 1986
  • Plywood used for construction as a decorative inner material is inflammable and can fire accident, causing destruction of human life and property. In this study, 3.5mm Kapur plywoods were soaked in the 23% monoammonium phosphate solutions by cold soaking method 3, 6, 9hrs and hot-cold bath method for 3/3hrs, and redrying was carried out by press-drying at the platen temperature of 110, 130, 160, 180$^{\circ}C$, and then fire test was carried out to investigate burning point, flame exhausted length, frame spread length, back side carbonized area and weight loss. The results are as follows; 1. In cold soaking method for 3, 6, 9hrs. retentions of monoammonium phosphate were 0.377, 0.448, 0.498kg/(30cm)$^3$ respectively, and in hot-cold bath method for 3/3hrs, the retention was 1.331kg(30cm)$^3$ that exceeded the minimum retention 1.124kg/(30cm)$^3$. 2. Correlation coefficients among the variable were shown in table 2. From the table, it could be recognized that there were close negative correlations between the treatment and burning point, flame spread length, back side carbonized area, flame exhausted time and weight loss, and there was negative correlation between treating time and back side carbonized area, but there was positive correlation between platen temperature and burning point. 3. From table 3, it can be observed that there were highly significant differences for burning point, flame spread length, flame exhausted time, back side carhonized area, weight loss between treatments. And in 2-way interactions, there were also highly significant for burning point, flame spread length, flame exhausted time, weight loss between time x treatment. 4. It was observed that burning point, flame exhausted time, flame spread length, back side carbonized area, and weight loss in fire-retardant treated plywood were the best effects in fire-retardant treated plywood, water treated plywood and nontreated plywood. In conclusion, I can estimate that absorbed chemical contents by hot-cold bath method for 3/3hrs, have a lot of effects on fire-retardant factors such as burning point, flame spread length, flame exhausted time, backside carbonized area and weight loss, but platen temperatures have a little effects on the fire factors.

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Quality characteristics of Aronia melanocarpa by different drying method (건조방법에 따른 아로니아의 품질특성)

  • Lee, Seul;Kim, Jong-Kuk
    • Food Science and Preservation
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    • v.22 no.1
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    • pp.56-62
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    • 2015
  • In this study, the quality characteristics of different drying methods of Aronia melanocarpa, which contains large amounts of bioactive substances, were investigated for the improvement of their practical use. During the drying period, the weight reduction was the highest with vacuum freeze drying (81.6%). The water content was reduced to the maximum level when vacuum freeze-drying was used. With regard to the color value measurement results, there were no significant differences in the $L^*$ value. Values of $a^*$ and $b^*$ were increased in vacuum freeze drying and cold air drying, but decreased in hot air drying. The hardness was increased dramatically after 36 hours of hot air drying, while with cold air drying, it increased slowly until 132 hr and increased rapidly after 132 hr. The dried yield was the highest with cold air drying (24.2%). As for the general component analysis results of Aronia melanocarpa, the moisture content was the lowest, and the crude protein and crude fat contents were the highest with vacuum freeze drying. No difference in pH value was shown among the dried Aronia melanocarpa obtained from the different drying methods, but the sugar content was the highest with vacuum freeze drying. The mineral content was the highest with cold air drying, and K, Ca, Mg, and Na were the major minerals. The free sugar content of dried Aronia melanocarpa was found to be 5.92~20.59 g/100 g, and the highest free sugar content was found with vaccum freeze drying.

A Study on the Interpretation of Sasangin(四象人)'s Constitutional Disease Names of Dong-uisusebowon(東醫壽世保元) 1901 edition(辛丑本) and Application to Clinical Diagnosis (『동의수세보원(東醫壽世保元)』 신축본(辛丑本) 병론(病論) 편명(篇名)의 해석(解釋)과 진단(診斷) 활용(活用)에 관(關)한 연구(硏究))

  • Yang, Young-kyu;Jeong, Chang-hyun;Jang, Woo-chang;Baik, You-sang
    • Journal of Korean Medical classics
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    • v.29 no.1
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    • pp.139-172
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    • 2016
  • Objectives : The purpose of research thesis is an advanced interpretation of the Name of Constitutional Disease of Dong-uisusebowon(東醫壽世保元) 1901 edition(辛丑本) evaluated to interpretation incompleted, and application of clinical diagnosis by rivised interpretation. Methods : A study on translation of sasangin(四象人)'s constitutional disease is researched the methods of documentary research on Dong-uisusebowon(東醫壽世保元) 1901 edition(辛丑本) and 1894 edition(甲午本). Results : Result of analysis of 4 meaning unit is as follows. Viscera or entrails means root or terminus of organ whom getting disease. Cold or heat based means being chilled or hot of triple energizer. Eexterior or interior means origin of disease of exterior or interior. Cold or heat means being chilled or hot of digestive system. Conclusions : In the clinical diagnosis using revised interpretaion, diagnosis of exterior or interior disease can be decided by symptoms of Taeyang syndrome(太陽病)'s fever and aversion to cold or not. Diagnosis of cold or heat disease can be decided by diarrhea or constipation.

A Study on Clothing Weight and Cornell Medical Index in Elderly Women (노인여성의 착의량과 건강관련변인)

  • Kim, Yang-Weon
    • Korean Journal of Human Ecology
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    • v.18 no.5
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    • pp.1087-1092
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    • 2009
  • From the environmental adaptation point of view, the clothing habits made by the thermal sensation and clothing weight of elderly women have changed according to the thermal sensation and health condition. The purpose of this study was to obtain the basic data for developing healthy and comfortable clothing for elderly women. Clothing weight, thermal sensation, clothing microclimate, resistance to cold and heat of 198 elderly women in Taejeon were surveyed from October 9, 2007 to October 19, 2007. 1. Clothing weight per body surface area was $830.4g/m^2$ of total clothing weight, $242.8g/m^2$ of underwear clothing weight, $617.3g/m^2$ of outerwear clothing weight, $419.8g/m^2$ of upper clothing weight, and $420.4g/m^2$ of lower clothing weight. 2. More than 90% of the respondents replied that they felt comfortable when the temperature inside the clothing was $33.5^{\circ}C$ and humidity inside the clothing was 30.2%. 3. The elderly women were more sensible to cold than to hot, those who felt cold had a tendency to wear heavier clothing. 4. The appeal rate for physical pain of older and lower income people, especially those with an income under 1,000,000 won, was higher than that of others. On the other hand, the lower the subjective economic level, the younger they were, and the more the monthly average income was, the higher the rate of mental pain. 5. The heavier the total clothing weight was, the higher the appeal rate for general pain.

Effects of Buja${\cdot}$Padu${\cdot}$Daehwang${\cdot}$Seokgo Extract on UCPs Expression in Mice (부자${\cdot}$파두${\cdot}$대황${\cdot}$석고 추출물의 UCP 발현에 미치는 영향)

  • Kwon, Kang-Beom;Kim, Eun-Kyung;Kim, In-Seob;Hwang, Tae-Ok;Lee, Si-Woo;Lee, Su-Kyung;Choi, Jin-Young;Keum, Kyung-Soo
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.21 no.6
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    • pp.1407-1410
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    • 2007
  • We designed to investigate the relationship the cold-hot theory of herbology and body temperature in experimental model. we prepared four kinds of oriental medicine, which consisted of two cold herbs, Daehwang and Seokgo, and two hot herbs, Buja and Padu. Decrease of body temperature by cold exposure for 12 hour was not inhibited by four herbs oral administration for two weeks. Thermogenesis in mammals is an essential physiological function to maintain the body temperature. Mitochondrial uncoupling proteins(UCPs), which have a potential to generate heat by uncoupling oxidative phosphorylation, apper to play a crucial role in thermogenesis. Therefore UCP is commonly recognized as a key molecule in metabolic thermogenesis and its dysfunction contributes to the development of obesity. In these experiments, Daehwang water extracts inhibited the UCP1 mRNA expression increase by cold exposure in brown adipose tissue. But other herbs did not significantly influence on UCPs mRNA expression in white adipose tissue and seleus muscle tissue. Based on this experiment, we will try to clarify the effects of Daehwang water extracts on UCP1 expression and function.

Effect of Ice and Hot packs on Balance, Proprioception and Muscle Strength in Young Adults with Knee Extensor Muscle Fatigue (젊은 성인의 근 피로가 발생된 무릎관절 폄근에 냉 찜질과 온 찜질의 적용이 균형, 고유수용성감각 및 근력에 미치는 영향 )

  • Heon-Ho Ha;Hee-Jin Jang;Dongyeop Lee;Ji-Heon Hong;Jae-Ho Yu;Jin-Seop Kim;Yeon-Gyo Nam;Seong-Gil Kim
    • Journal of the Korean Society of Physical Medicine
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    • v.18 no.4
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    • pp.121-131
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    • 2023
  • PURPOSE: The purpose of this study was to evaluate the effects of ice and hot packs on proprioception, balance, and muscle strength in knee extensor muscle fatigue. METHODS: A total of 31 male and female students in their twenties from a university in A, Chungnam, Korea, were selected as participants. Three experiments were conducted to assess static balance, dynamic balance, proprioception, and muscle strength before and after induction of muscle fatigue, and following intervention. RESULTS: In the case of stability typical (ST), a significant difference was observed in pillow with eye open (PO) when a Hot pack was applied (p < .05). The weight distribution index (WDI), showed significant differences in normal eye open (NO) and Normal eye closed (NC) tests when ice packs and hot packs were applied (p < .05). In the dynamic balance assessment using Y-balance, significant differences were observed in all values except for pre- and post-intervention in the medial and lateral directions (p < .05). The recovery of proprioceptive sensation showed a significant difference when ice packs were applied (p < .05). In muscle strength, significant differences were observed in all comparisons between measurement time points (p < .05). CONCLUSION: Rest was most effective for static balance, and cold and warm compresses were most effective in recovering dynamic balance. For proprioception, cold compresses were most effective. Muscle strength had a positive effect on recovery in all three intervention methods. These results show that cold and warm compresses can be useful in the recovery of various functions related to muscle fatigue.

A Study on Concrete Material Quality Management Based on Various Test of Construction Condition under Hot Weather Circumstance (서중(暑中) 환경에서 현장 콘크리트 시험을 통한 재료 품질관리 방안)

  • Park, Shin
    • Journal of the Korea Institute of Building Construction
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    • v.5 no.3 s.17
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    • pp.91-99
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    • 2005
  • It is required to study systematical on the concrete quality management to extend structure life because rebuilding effect is reducing under present condition of large sized and high stories structure. Concrete, which shows its intensity by hydrating action and a big change in quality according to hot weather and temperature, produces a lot of qualify problem under hot and cold weather Because of each specification and construction plan which does not have basic standard on site, concrete's quality is irregular and makes some defect. As a result, Daegu is turned out to be the longest area after investigating application period and days focused on 8 cities weather information about relationship between hot weather circumstance and construction environment. Therefore, we first surveyed the concrete material in the region and found out the problem of quality nanagement. Then figure out the way of solution. Moreover, we integrated concrete material quality management, which is applied differently to each site, to have equal quality and to reduce defect from construction site. And then, based on various test of construction condition and analysis of quality management item, we suggest effective concrete quality management to make concrete material construction standard guide and plan under hot weather.

Field Application to Evaluate the Effect of Various Surface Covered Curing Blankets on Temperature Profile and Crack Occurrence of the Concrete under Hot Weather Condition (서중환경에서 표면피복 양생재 종류변화가 콘크리트의 초기 온도이력 및 균열발생에 미치는 영향에 관한 현장적용성 평가)

  • Han, Min-Cheol;Lee, Sang-Woon
    • Journal of the Architectural Institute of Korea Structure & Construction
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    • v.34 no.5
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    • pp.27-34
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    • 2018
  • Concrete placed under hot weather condition suffers from larger slump loss, rapid moisture evaporation due to high air temperature. Proper measures for material, transportation and curing should be taken to prevent the quality deterioration of the concrete under hot weather condition. In Korea, Although the period of hot weather concrete in Korea occupies only 2 months, there are a lot of quality problems including plastic, drying shrinkage and cold joint. Therefore, the objective of this paper is to investigate and compare the temperature history and crack occurrence of the concrete, which was placed in the actual apartment house construction field under hot weather condition, in response to the application of surface covered curing blankets including PE film, single layer clear bubble sheet, white colored bubble sheet and aluminum metalized bubble sheet. Test results indicated that the application of white colored bubble sheet and aluminum metalized bubble sheet showed most favorable results in terms of reduction in temperature rise and crack occurrence as well as easiness in handling. But, due to light reflection by aluminum metalized bubble sheet, it is believed that white colored bubble sheet is preferable.