• Title/Summary/Keyword: cold and heat

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Tension/Heat/Thermal Deformation Analysis of a Cold Coiled Strip in Coiling Process (냉연 판재의 권취공정에 있어서 장력/열/변형 해석)

  • 정영진;이규택;강충길
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2002.05a
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    • pp.39-43
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    • 2002
  • A new model for heat transfer and thermal deformation analysis according to strip mm in coiling process has been proposed. Finite difference analyses for heat transfer of cold rolled coil have been carried out under various coiling tensions and strip crown using the equivalent thermal conductivity for the radial direction of cold rolled coil which is a function of strip thickness, surface characteristics and compressive pressure. The compressive pressure is calculated from a equation expressed as a function of hoop stress and coil tension considering strip mm obtained by experiment. Finite element method for thermal deformation of cold rolled coil has been performed to investigate the effects of the strip crown, the coil tension and temperature. From these analyses, it is found that the axial inhomogeneity of thermal deformation is increased as the strip crown, compressive pressure, and temperature drop in cold coiled strip increase.

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Analysis of the Efficiency of Improved Bubble Sheet for Heat Curing in Cold Weather

  • Choi, Hyun-Kyu;Son, Myung-Sik;Han, Cheon-Goo
    • Journal of the Korea Institute of Building Construction
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    • v.13 no.1
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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.

A Study on Heat Treatment for Improving Cold Forgeability of a Bearing Steel, SUJ2 (베어링강 SUJ2의 냉간 단조성 향상을 위한 열처리에 관한 연구)

  • Kim, Hae-Ji
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.8 no.1
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    • pp.24-30
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    • 2009
  • In this paper, the effect of heat treatment on forgeability is investigated and an improved heat treatment cycle is proposed for the bearing steel, SUJ2. An application example of a bearing inner race cold forging, which has small cracks in the bottom after backward extrusion and piercing, is found from a cold forging industry. The process is evaluated by finite element analysis and several heat treatment cycles are examined in order to propose an improved heat treatment cycle. The effect of heat treatment on material hardness and tool life, dimensional accuracy and forming load is revealed through experiment.

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The Investigation of Literature about fever (발열(發熱)에 관(關)한 문헌적(文獻的) 고찰(考察) -(황제내경(黃帝內經)을 중심(中心)으로)-)

  • Gyun, Hyun;Jeong, Seung-Gi;Lee, Hyeong-Gu
    • The Journal of Internal Korean Medicine
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    • v.11 no.1
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    • pp.1-13
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    • 1990
  • We objerved the following results from The Yellow Emperior's Canon of Internal medicine through the investigation of literature about fever. 1. Fever is divieded two type asthenic fever sthenic heat and It accused two type of excess of Yang-exoganous heat, deficiency of Yin-internal fever 2. The cause of fever is divieded three type, exoganous cause, internal cause non-exoganouse and internal cause Among the cause of fever Exoganous cause is almost affected by cold-evil Internal cause is affected by deficiency of Yin and seven emotion caused by having sex after intoxigation or over-exertion, and non-exoganous and internal cause bring about the difference of a personal life and food and drink 3. The sympton produced by fever is appeared differently through-pulse and meridian and they are indication of Diagnosis 4. The theory of treatment about fever are as follows Drinking cold-water Practising acupuncture Trerating hot-evil by cold Dispel cold by warm Treating cold-evil by heat Promote vital energy circulation by cold Treating warm-evil by cold Promating circulation by cold Treating cold-evil by warm Promoting circulation by heat.

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A study on the characteristic of electrogastrography according to the heat-cold patternization (한열성향에 따른 위전도 특성 연구)

  • Haa, Song-Yong;Kim, Min-Yong;Park, Young-Jae;Park, Young-Bae
    • The Journal of the Society of Korean Medicine Diagnostics
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    • v.12 no.1
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    • pp.131-141
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    • 2008
  • Background: In relation to a diagnosis of Korean Medicine, heat-cold is one of the most important indicators for evaluation. In spite of this importance, there has not been the study that tries to examine the change of indicators in an electrogastrography (EGG) according to the heat-cold patternization. Objective: The objective of this study is to establish the correlation between the heat-cold patternization and indicators of EGG by means of Standardized Questionnaire for Heat-Cold Patternization. Method: To conduct this study, we used the method as follows: Before conducting EGG, subjects were requested to give answers to the questionnaire which was developed by Kim. Before EGG, subjects were demanded to fast for more than 8 hours and then eat the test meal. Before eating the test meal(test meal: two slices of bread, 4oz of apple juice), EGG signals were detected for 30 minutes, and then subjects could eat the test meal for 10 minutes. After eating the test meal, EGG signals were detected for 30 minutes. Results: 1. There was a negative correlation between heat score and the power ratio of channel 1 and channel 2 of EGG. There was a positive correlation between cold score and the power ratio of channel 1 of EGG. 2. There was a positive correlation between heat score and pre-prandial gastric arrhythmia in the channel 1, 2 and 4 of EGG. There was a negative correlation between cold score and post-prandial gastric arrhythmia in the channel 1, 2 and 3 of EGG. 3. There was a negative correlation between heat score and normal pre-prandial gastric slow wave in the channel 1, 2 and 4 of EGG. There was a positive correlation between cold score and normal post-prandial gastric slow wave in the channel 3 of EGG. Conclusions: From the results above, we could conclude as follows: Indicators of EGG and cold score presented a positive correlation, and heat score displayed a negative correlation. As a result, to apply EGG to a diagnosis of functional indigestion, the application of EGG to subjects who have heat patternization would increase the reliability of a diagnosis.

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Differences of Cold-heat Patterns between Healthy and Disease Group (건강군과 질환군의 한열지표 차이에 관한 고찰)

  • Kim Ji-Eun;Lee Seung-Gi;Ryu Hwa-Seung;Park Kyung-Mo
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.20 no.1
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    • pp.224-228
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    • 2006
  • The pattern identification of exterior-interior syndrome and cold-heat syndrome is one of the diagnostic methods using most frequently in Oriental medicine. There was no systematic studies analyzing the characteristics of the 'exterior-interior and cold-heat' between healthy and disease group. In this study, cold-heat pattern, blood pressure, pulse rate, height and weight are recorded from 100 healthy subjects and 196 disease subjects with age ranging from 30 to 59 years. To analyze the differences between healthy and disease group, we used the descriptive statistics. And linear regression function, linear support vector machine and bayesian classifier were used for distinguishing healthy group from disease group. The score of both exterior-heat and interior-cold in healthy group is higher than the score in disease group. This means that if one belongs to the disease group, his(or her) exterior gets cold and his interior gets hot. And also, these result have no relevance to age. But, the attempt to classify healthy group from disease group with a exterior-interior and cold-heat and other vital signs did not have good performance. It mean that even though they have a different trend each other, only these kinds of information couldn't classify healthy group and disease group.

Preliminary Study on Usual Cold or Heat as a Risk Factor for Hypertension in an University Faculty (일개 대학 교직원 집단에서 고혈압의 위험요인으로서의 평소 한열 예비 연구)

  • Jung, Kyung Sik;Kim, Yun Young;Baek, Young Hwa;Jang, Eunsu
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.33 no.4
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    • pp.226-232
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    • 2019
  • This study was aimed to reveal that the usual cold or heat state was associated with hypertension and could be a risk. We emailed educational personnel in D university to join this study and 182 subjects participated in from March to December in 2016. The usual cold or heat diagnosis was conducted by two experts who had over 10 years expertise. The blood pressure was measured from the subjected after 10 minute rest with Jawon medical device. The hypertension was diagnosed by the guide of the Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure. The frequency analysis was used in general characteristics, Pearson's Correlation Coefficient analysis was conducted in among continuous variables, and chi-square test was also used between hypertension and cold or heat group. Logistic regression was analyzed to generate the odds ratios (ORs) and 95% confidence interval (CI) for hypertension. The cold score was suggested to have negative association with Body mass Index (BMI, -.374, p<.001), systolic blood pressure (-.333, p<.001), and diastolic pressure (-.261, p<.001). The heat score was analyzed to have positive association with Body mass Index (.413, p<.001), systolic blood pressure (.249, p<.001), and diastolic pressure (.156, p<.001). The distribution of the cold group (35.1%) and non-cold group (64.9%) in hypertension was significantly different (p=0.18). The distribution of the heat group (62.2%) and non-heat group (37.8%) was significantly different (p=0.27). The usual cold was associated with decreased ORs (ORs 0.405, 95% CI=0.191-0.857), and usual heat was associated with increased ORs (ORs 2.327, 95% CI=1.108-4.888). However, after adjusting body mass index, sex, and smoking, the association was not significantly different. It is possible that usual cold or heat associate with hypertension. Further study is needed to show that usual heat may be a independent risk factor for hypertension through follow up design.

Effects of Taste and Quality of Drugs on the Plasma Corticosterone Level in Mice exposed to Heat and Cold Stress (한약(韓藥)의 기미(氣味)가 한열자극(寒熱刺戟)을 받은 생쥐의 혈중(血中) corticosterone에 미치는 효과(效果))

  • Nam Yeo-Jeong;Lee Tae-Hee
    • Herbal Formula Science
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    • v.10 no.1
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    • pp.157-167
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    • 2002
  • This study was performed to investigate what effect the taste and quality of drugs would have on the cold and heat mechanisms of human body. We administered Hwangryeunhaedok-tang composed of bitter-tasted, cold-qualified drugs and Gungangbuza-tang composed of spice-tasted. hot-qualified drugs, respectively to the mice 1 hr before exposure to heat stress or cold stress. Plasma corticosterone level of mice was measured. The results were as follows: 1. The elevated corticosterone level in the mice exposed to heat stress was significantly decreased after administration of Gungangbuza-tang but there was no decrease after administration of Hwangryeunhaedok-tang. 2. The elevated corticosterone level in the mice exposed to cold stress was significantly decreased after administration of Hwangryeunhaedok-tang but there was mild decrease after administration of Gungangbuza-tang. 3. When the doses, 3g/kg and 1g/kg were administerd to mice exposed to heat stress. both dose showed significant decrease of corticosterone level and the dose. 3g/kg was more effective. However, in the mice exposed to cold stress, the dose, 3g/kg showed mild decrease and 1g/kg showed significant decrease. These data suggested that HW decreased the plasma corticosterone level in the mice exposed to cold stress and GB also decreased the plasma corticosterone level in the mice exposed to heat stress. In conclusion, our study revealed that the taste and quality of drugs controled the cold and heat mechanism of human body.

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A Study on Cooling Systems with Cold Water Panels in the Walls of Small Buildings (소형 건축 벽면의 냉수 패널에 의한 냉방시스템에 관한 연구)

  • Cho, Dong-Hyun;Jo, Myeong-Gi
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.18 no.10
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    • pp.20-26
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    • 2019
  • This study was conducted on cooling systems in which, for the first time at home and abroad, cold water panels are embedded in the walls of small buildings for radiant cooling by heat absorption with cold water. In summer, cold water is circulated through cold water (chiller) circulation tubes embedded in three walls (two side walls and one rear wall) of a building to implement radiant cooling by the coldness of the water. From the results of this study, the experimental and theoretical natural convection heat transfer coefficients were relatively well-matched over the entire experimental range, thereby verifying the reliability of the experimental results. The surface temperature reduction rate of the walls in which cold water panels are embedded was large whereas that of the walls where no cold water panels are embedded was very small.

A Study on the Effect of Moxibustion at Shinmun(H7) according to Cold or Heat Tendency (한열성향(寒熱性向)에 따른 신문혈(神門穴) 애구(艾灸) 효능(效能)의 비교(比較) 연구(硏究))

  • Kim, Dong-hoon;Kim, Jong-deog;Kim, Eun-jung;Kim, Kyung-tae;Rhu, Seong-ryong;Jung, Ji-chul;Park, Young-bae
    • Journal of Acupuncture Research
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    • v.21 no.4
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    • pp.135-147
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    • 2004
  • Objective: Moxibustion is one of major healing technique in oriental medicine. It has been widely used in many disease. There is an text which suggest moxibustion is more efficient to the situation of han(寒) and heo(虛) than yeal(熱) and sil(實) in Huangdineijing <黃帝內經>. The aim of this study is to research the effect of moxibustion at Shinmun(H7) is different according to cold or heat tendendy man by analyzing the electroencephalogram(EEG). Methods: We classified objects by their cold or heat tendency using questionnare for cold - heat patternization. (12 cold tendency man, 19 heat tendency man) Before and after moxibustion at Shinmun(H7), EEG raw data were measured during 5 minutes. The correlation dimension(D2), the correlation dimension variability rate(${\Delta}D2$), largest lyapunov exponent(L1) and largest lyapunov exponent variability rate(${\Delta}L1$) were calculated. We analyzed D2, ${\Delta}D2$, L1, ${\Delta}L1$ to see the effect of moxibustion at Shinmun(H7) was statistically different according to Cold or Heat tendendy man. Results : Paired t-test showed significant differences between before and after moxibustion at Shinmun(H7) on the Fp2 in D2(p<0.05), on the Fp2, F3 and F4 in ${\Delta}L1$(p<0.05). Student Hest showed significant differences between cold and heat tendendy man on the F3 in ${\Delta}L1$(p<0.05). Conclusion: These results suggest that moxibustion at Shinmun has an effect on stabilizing mind and it is more efficient to the cold tendendy man than the heat tendendy man.

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