• Title/Summary/Keyword: Cold-Heat

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Theory study on thermal performance of metal foam

  • Jin, Meihua;Kim, Pil-Hwan;Lee, Hae-Jong;Jeong, Hyo-Min;Chung, Han-Shik
    • Proceedings of the SAREK Conference
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    • 2008.11a
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    • pp.239-243
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    • 2008
  • In many literatures the researchers pointed out that the using metal foam will significantly enhance the performance of heat exchanger. This paper focuses on theory study of metal foam, including calculation method of properties of foam (permeability ��K, inertial coefficient f, fiber diameter $d_f$, and effective conductivity $k_e$), model of pressure drop and model of heat transfer. Theory analysis on the performance of heat exchanger will be presented here. Finally the optimal material will be obtained from theory calculation.

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Relationships between depression, anxiety, 'exterior-interior pattern and cold-heat pattern' and Heart Rate Variability in healthy Subjects (건강인의 표리 한열 변증, HRV, 우울, 불안 지표의 상관성 분석)

  • Kim, Ji-Eun;Lee, Jeong-Chan;Kang, Hee-Chul;Lee, Seung-Gi;Park, Kyung-Mo
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.20 no.2
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    • pp.482-487
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    • 2006
  • The identification of the exterior-interior pattern and the cold-heat pattern is one of the most frequently used diagnostic methods in Oriental medicine. No systematic studies, however, have yet been conducted to determine the emotional and autonomic factors involved in the exterior-interior and cold-heat. In this study, the relationships between depression, anxiety, and the exterior-interior and cold-heat patterns in 100 healthy female volunteers with a mean age of 42.77 were also investigated. The autonomic nervous system's control of human temperature is a well known fact. Thus, this paper also aimed to investigate the correlationof the autonomic nervous system and patterns of the exterior-interior and cold-heat. The analysis of heart rate variability (HRV), which has become a popular non-invasive tool for assessing the activities of the autonomic nervous system, was conducted in this study. No relationship was found between the exterior-interior and cold-heat pattern scores and the degree-of-depression scores. But there was a significant difference between the exterior-interior and cold-heat pattern scores of the different anxiety types, and between those of the different anxiety levels. The depression and anxiety levels also had an effect on the HRV indices.

The Agreement in Cold-Heat and Health Status among Sasang Constitutional Experts in Diagnosis of Sasang Pathological Symptoms (사상의학 병증진단에 있어서 사상의학 전문가의 한열 특성 및 건강상태 평가에 관한 일치도 연구)

  • Jin, Hee-Jeong;Kim, Sang-Hyuk;Dong, Sang-Oak;Jang, Eun-Su;Lee, Si-Woo
    • Journal of Sasang Constitutional Medicine
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    • v.26 no.2
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    • pp.146-155
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    • 2014
  • Objectives In Sasang Constitutional medicine(SCM), it is an important factor to assess the degree of cold/heat and healthy status. We purposed to check the agreement among the experts on the assessment of cold/heat and healthy status. Methods Six SCM experts and 10 healthy volunteers were recruited for this study. The SCM experts had an interviewed with each volunteer in the similar condition like that of the actual clinic. And then the expert evaluated each volunteer's cold/heat and healthy status. Intraclass correlation coefficient(ICC) was used to measure the interrater reliability and interrater agreement among the experts. Results Two volunteers are excluded due to the missing data, therefore eight persons' data (3 males and 5 females) were included in our analysis. The mean of age and BMI are 21.73(${\pm}2.32$) and 29.63(${\pm}4.66$), respectively. In health status, cold status and heat status, the ICC was 0.789, 0.904, 0.925, respectively. Conclusions We found that the assessment of cold/heat and healthy status was continued reliable among SCM experts. The assessment of cold/heat status was more consistent than the assessment of healthy status.

Proposal of Form-Color-Pulse-Symptom Diagnostic System for Enhancement of Diagnostic Rate of 8 Principle Pattern Identification - Focusing on Cold Heat Pattern Identification - (팔강변증의 진단율 향상을 위한 형색맥증진단(形色脈證診斷)시스템 설계 - 한열변증을 중심으로 -)

  • Chi, Gyoo Yong;Lee, In Seon;Jeon, Soo Hyung;Kim, Jong Won
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.33 no.3
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    • pp.163-168
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    • 2019
  • In order to enhance the 8 principle pattern diagnosis rate comparing with diagnostic method by self-report questionnaire on cold/heat pattern in the clinical practice, a new diagnostic method using form-color-pulse-symptom (FCPS) system is proposed. FCPS system is composed of outputs of cold/heat pattern through the calculation process of contribution degree to the cold, heat pattern and qi, blood, yin, yang deficiency patterns, based on analysis of 16 mechanisms of disease calculated by diagnostic system of oriental medicine (DSOM) first. And second component is an output of differentiated 8 principle patterns in detail through binding and calculating process with digital informations of pulse, color, form, constitution obtained by computerized measurement system. Putting together above two processes consecutively, cold-heat complex or true/false cold/heat patterns and personalized characters of cold/heat patterns of each patient can be subdivided through a computation method of determining each pattern. In conclusion, 8 principle pattern identification can be performed more accurately using FCPS system than existent self report questionnaire method. These hypothetic proposal is needed to be proven by clinical trial for the future and then the accurate numbers used in each calculational function should be revised properly.

Association between cold-heat symptoms and sleep disturbances according to the Sasang constitution: a cross-sectional community study

  • Hyun, Min Kyung;Yoshino, Tetsuhiro
    • Journal of Society of Preventive Korean Medicine
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    • v.26 no.1
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    • pp.59-74
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    • 2022
  • Objectives : Evidence supporting the cold-heat symptom and sasang constitution type, which are diagnostic items of traditional Korean medicine, is needed to manage sleep disturbances, which is a typical symptom of mibyeong (subhealth). This study examined the association between each cold-heat symptom and sleep disturbances according to each sasang constitution type. Methods : This research was a cross-sectional study of 5,793 subjects from the Korean Medicine Data Center (KDC) community cohort survey. The association between each cold-heat symptom and sleep disturbances was analyzed by logistic regression analysis adjusted for several demographic variables. Subgroup analysis was then performed for each type of sasang constitution. Results : The soeum and soyang types were 1.53 and 1.26 times more likely to have sleep disturbances than the taeum type. Sleep disturbances were associated with 'coldness of the abdomen', 'watery mouth' in the cold domain items, and 'body feverishness', 'flushed face and eye', 'thirst', and 'scanty dark urine' in the heat domain items. The soeum and soyang types were 1.55 and 1.39 times more likely to sleep less than five hours per night than the taeeum type. In addition, the associations of those showed a different pattern for each sasang constitution type. Conclusions : Sleep disturbances are associated with specific cold-heat symptoms, and the associated cold-heat symptoms differ according to the sasang constitution type. These results may help traditional medicine specialists select customized interventions for patients with sleep disturbances.

Analysis of Counterflow Heat Exchangers with the Concept of Available Energy (가용에너지를 이용한 대향류 열교환기의 해석)

  • 김수연;정평석
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.16 no.11
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    • pp.2189-2195
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    • 1992
  • The performance of heat exchanger as an energy conversion device can be described by the available energy output and efficiency. The efficiency is defined as the ratio of the available energy output and the exergy of the heat source flow. In present study, a counterflow heat exchanger is analyzed and the conditions to obtain maximum output is numerically determined. As a result, the avilable energy obtained by the cold flow can be determined as functions of the heat capacity flow, the cold flow inlet temperature and the heat transfer capacity of heat exchanger. At the maximum output condition the heat capacity flow of the cold fluid is larger than that of the heat source, and the heat capacity flow ratio is equal to the ratio of the cold flow inlet temperature and the atmospheric temperature. And the avilable energy output increases as the heat transfer capacity of the heat exchanger become larger, but in the economic point of view there is also an optimum heat transfer capacity for a given heat source flow.

Characteristics of Atmospheric Circulation and Heat Source related to Winter Cold Surge in Korea (한반도 겨울철 한파와 관련된 대기 순환과 열원의 특성)

  • Kim Maeng-Ki;Shin Sung-Chul;Lee Woo-Seop
    • Journal of the Korean earth science society
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    • v.26 no.6
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    • pp.560-572
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    • 2005
  • This study investigates the characteristics of atmospheric circulation and the heat source $(Q_1)$ related to the winter cold surge in Korea from 1979 to 1999. The occurrence frequency of cold surge is about one event per year and $60\%$ of the total events occurred during the former period, before 1989. During the cold surge, the pressure pattern shows more dominant east-west dipole circulation pattern in the lower troposphere and the effect of upper level trough is stronger than normal cases. Temperature falling pattern over Korea shows that the pattern opposite to the temperature structure over Lake Baikal and temperature change has opposite signs between the low-middle level and upper level, with the boundary at 400 hPa. The analysis of heat source shows that atmospheric cooling by cold advection during the cold surge is balanced by adiabatic warming due to downward motion, indicating that the movement path of cold core is associated with that of heat sink. Therefore, the movement mechanism of the heat source and sink should be well known for understanding the maintenance mechanism of cold surge and predicting cold surges.

Influences of Ice Microphysical Processes on Urban Heat Island-Induced Convection and Precipitation (얼음 미시물리 과정이 도시 열섬이 유도하는 대류와 강수에 미치는 영향)

  • Han, Ji-Young;Baik, Jong-Jin
    • Atmosphere
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    • v.17 no.2
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    • pp.195-205
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    • 2007
  • The influences of ice microphysical processes on urban heat island-induced convection and precipitation are numerically investigated using a cloud-resolving model (ARPS). Both warm- and cold-cloud simulations show that the downwind upward motion forced by specified low-level heating, which is regarded as representing an urban heat island, initiates moist convection and results in downwind precipitation. The surface precipitation in the cold-cloud simulation is produced earlier than that in the warm-cloud simulation. The maximum updraft is stronger in the cold-cloud simulation than in the warm-cloud simulation due to the latent heat release by freezing and deposition. The outflow formed in the boundary layer is cooler and propagates faster in the cold-cloud simulation due mainly to the additional cooling by the melting of falling hail particles. The removal of the specified low-level heating after the onset of surface precipitation results in cooler and faster propagating outflow in both the warm- and cold-cloud simulations.

Effectiveness of herbal ointment Biyeom-go according to cold-heat pattern identification: a subgroup analysis on patients with rhinitis (한열(寒熱) 변증에 따른 한의 외용 치료제 비염고의 치료 효과 : 하위 그룹 분석)

  • Son, Mi-Ju;Lee, Dong-Hyo
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.32 no.4
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    • pp.29-40
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    • 2019
  • Objectives : Hwanglyeonhaedok-tang(黃連解毒湯) is a representative herbal formula with "clear heat(淸熱)" effects. The aim of this study was to evaluate the effects of Hwanglyeonhaedok-tang-based intranasal herbal ointment Biyeom-go based on the cold and heat pattern identification questionnaire(CHPIQ). Methods : We performed a subgroup analysis of the previously published prospective observational study. A total of 58 patients with rhinitis were administered Biyeom-go for 4 weeks, and its effects on the Total Nasal Symptom Score(TNSS), Mini Rhinoconjunctivitis Quality of Life Questionnaire(Mini-RQLQ) score, and nasal endoscopy index score were analyzed based on CHPIQ. Results : Among the 58 patients, the heat and non-heat patterns were shown by 39 and 19 patients, respectively, while the cold and non-cold patterns were shown by 46 and 12 patients, respectively. The change in TNSS from baseline negatively correlated with the heat pattern score(p=0.011). Improvement in TNSS was greater in the heat pattern group than in the non-heat pattern group, with a borderline significant difference(p=0.07). Mini-RQLQ and nasal endoscopy index scores tended to be lower in the heat pattern group than in the non-heat pattern group, but without a statistically significant difference. Conclusion : The findings indicate that CHPIQ is a useful tool for the diagnostic and prognostic evaluation of patients with rhinitis. This study provides fundamental evidence of the close association between the cold-heat pattern in patients with rhinitis and the treatment effects of Biyeom-go.

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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