• Title/Summary/Keyword: fatigue factor

Search Result 1,217, Processing Time 0.033 seconds

Development and Preliminary Validation of Mibyeong Questionnaire(MQ) Based on Deficiency-Stagnation pattern (허울(虛鬱) 기반 미병 평가도구 개발 및 예비타당성 검증)

  • Baek, Younghwa;Lee, Youngseop;Park, Kihyun;Lee, Siwoo;Yoo, Jonghyang
    • Journal of Society of Preventive Korean Medicine
    • /
    • v.19 no.3
    • /
    • pp.11-19
    • /
    • 2015
  • Objective : This study aimed to develop and preliminary validate the Mibyeong Questionnaire (MQ) based on Deficiency-Stagnation pattern, which was report of a person's health condition that comes directly from the person. Method : The first phage of developing a MQ was to generate and exhaustive list of all MQ issue that are relevant to the domain of interest, using literature research and expert group discussions. Through those steps, we established MQ with 33 items divided into two parts: 21-item deficiency pattern and 12-item stagnation pattern. The second phage, we examined the preliminary tests of reliability and validity including the 16-item Deficiency of MQ (16D-MQ), with data (n=1,890) already collected on the Korean medicine data center in KIOM. Results : Exploratory factor analysis revealed three factors of the 16D-MQ. These factors were fatigue(Qi, 氣); psychic and physical elements(Shen, 神); and skin and hair(Jing, 精). Cronbach's coefficient alpha was 0.876 and the intraclass correlation coefficients was 0.368-0.538. In support of criteria validity, the 16D-MQ was weakly correlated with EQ-5D and physicians's opinion, but it was acceptable. Conclusion : The MQ shows that it has an appropriate level of internal consistency and validity. We think further study to reveal its reliability and validity, including stagnation pattern as well as deficiency pattern, is needed.

A Study on Characteristic of Fracture in Lap Joint Welded STS429L (STS429L 겹침 용접부의 파단 특성에 관한 연구)

  • Choi, Dong-Soon;Kim, Jae-Seong;Kim, Hyun-Jae;Lee, Bo-Young
    • Journal of Welding and Joining
    • /
    • v.27 no.5
    • /
    • pp.49-54
    • /
    • 2009
  • Recently, a demand of ferritic STS is increasing rapidly in automobile exhaust system. Exhaust manifolds are the part nearest to the engine so that the material is exposed to high temperature exhaust gas. Excellent heat resistant properties, especially high temperature strength, thermal fatigue resistance and high corrosion resistance are necessary for these parts. STS429L contains 15 weight percent of Cr and low Mo, so has good price competitive. And it has excellent high temperature strength and corrosion resistance, so receives attentions as material that applying to exhaust manifold. In tensile test of lap joint welded STS 429L, most of specimens are failed in base metal, but occurs brittle fracture in weld metals at some specimens in the face of good welding conditions. In the process of tensile test, lap joint welded STS429L specimens are transformed locally. The brittle fracture occurs that local transforming area exists in weld metals. But, butt welding specimens made by same materials showed ductile fracture in tensile test and bending test. In this study, suppose the reason of brittle fracture is in the combined local transform and tensile stress, through analysis of bead geometry, evaluate geometrical factor of brittle fracture in lap joint welded STS429L.

Effect of Surface Profiles on Pavement Fatigue Life (포장 프로파일이 포장 피로수명에 미치는 영향 분석)

  • Park, Dae-Wook;An, Deok-Soon;Kwon, Soo-Ahn
    • International Journal of Highway Engineering
    • /
    • v.11 no.2
    • /
    • pp.167-174
    • /
    • 2009
  • The simulation of dynamic load was conducted based on surface profile on asphalt concrete pavement, vehicle speeds, and suspension types using a truck simulation program. The results of the simulated dynamic load based on different surface profile, vehicle speeds, and suspension types are analyzed. As pavement roughness and vehicle speed are increased, the dynamic load was increased. Walking beam suspension produces greater dynamic load than air spring suspension. Pavement damage index is calculated based on covariance of dynamic load and Paris-Erdogan fracture parameter, n which is based on creep compliance tests of asphalt mixtures used in Korea. The higher covariance of dynamic load, confidence level, and fracture parameter are used, the greater pavement damage index is obtained. Specification of pavement roughness can be developed in various vehicle speeds and asphalt mixtures, and pay factor can be determined after constructing asphalt concrete pavement using pavement damage concepts.

  • PDF

A Study on the Relationships between Breathing Disorders and Pathological Patterns Based on the Cold-Heat, Phlegm-, Yin Deficiency-, Lao Juan (勞倦)-Pattern Questionnaires and the Nijmegen Questionnaire (호흡실조와 증형간 연관성 연구: 한열, 담음, 음허, 노권 및 네이메헨 설문을 중심으로)

  • Hong, Hanna;Oh, Hwan-Sup;Park, Young-Bae;Park, Young-Jae
    • Journal of Oriental Neuropsychiatry
    • /
    • v.27 no.4
    • /
    • pp.215-221
    • /
    • 2016
  • Objectives: The purpose of this study was to examine the relationship between pathological patterns and hyperventilation syndrome, using pathological pattern and Nijmegen questionnaires. Methods: 33 healthy adults were asked to complete the Cold-Heat-, Phlegm-, Yin deficiency, and Lao Juan (勞倦)-pattern questionnaires, the Chalder fatigue scale, and the Nijmegen questionnaire at Kyung Hee University Hospital. We performed Pearson correlation analyses between the pathological pattern questionnaires and the Nijmegen questionnaire. The questionnaires were composed of several factors. Therefore, each factor and Nijmegen questionnaire score were also analyzed. Results: All of the pattern questionnaire scores had a positive correlation with the Nijmegen questionnaire score. The phlegm pattern, in particular, and the LaoJuan (勞倦) questionnaire scores had high correlation coefficients. The coefficient for the phlegm pattern was 0.856 and the coefficient for the LaoJuan (勞倦) pattern questionnaire was 0.855. Conclusions: The results mean that the pathological pattern questionnaires could be one of the reference materials to evaluate hyperventilation syndrome. Furthermore, improvement of pathological patterns may be helpful for treating hyperventilation syndrome, together with conventional therapies including breathing training.

Optimal Design using Flow-structure Interaction Analysis Method of Engine Generator Cooling Fan (엔진발전기 냉각팬의 유동-구조 연성해석 기법을 이용한 최적설계)

  • Kim, Seung Chul
    • Journal of the Korean Institute of Gas
    • /
    • v.24 no.3
    • /
    • pp.47-53
    • /
    • 2020
  • In this study, the optimization design data was presented by analyzing the performance and durability of the cooling fan by one-way fluid-structure interaction analysis of the cooling fan shape used in the engine generator. For this purpose, a steady-state analysis was performed on the flow field inside the cooling fan, and the durability was analyzed by using the steady-state calculation results as input data for structural analysis. Six types were modeled for fluid analysis by changing the blade and sweep angle of the cooling fan, and the ratio of mass flow rate and torque was best in A type, but B type with relatively large mass flow rate was the best. It was judged to have flow performance. As a result of examining the structural analysis by setting the four blade thickness of the B type selected through the fluid analysis, it was judged that B Type-3 is the most suitable when considering the fatigue safety factor.

Momordica charantia extract supplementation tend to affect improvements in body composition and metabolic parameters on tennis players: A pilot study

  • Kwak, Jae-Jun;Yook, Jang Soo;Ha, Min-Seong
    • Journal of the Korean Applied Science and Technology
    • /
    • v.36 no.4
    • /
    • pp.1164-1171
    • /
    • 2019
  • Dietary supplements derived from natural sources are an essential factor in optimizing athletic performance. It has been proposed that the extract of Momordica charantia (M. charantia) that is known as a bitter melon can be potentially used as a novel supplement for health promotion. This pilot study aimed to examine the effects of the M. charantia extract when administered in the form of a sports drink, and we evaluated changes in body composition and metabolic factors in tennis players after 4-week consumption of the extract. Eight male college tennis players were instructed to consume an M. charantia extract 6 times per day (3 in the morning and 3 in the afternoon, and the total daily intake was 600 ml). Collected data were analyzed using paired t-tests to examine the changes over time after consumption of the M. charantia extract. The results revealed a significant increase in the trunk muscle mass, basal metabolic rate, and daily calorie intake (p < 0.05). Levels of protein, minerals, and total body water showed an increased tendency (not statistically significant), whereas intracellular water and extracellular water showed a decreased trend. Furthermore, fat-free mass, skeletal muscle mass, and muscle mass showed an increased tendency. In conclusion, consumption of the M. charantia extract caused an increase in parameters related to protein, muscle mass, and metabolism. It seems that follow-up studies related to fatigue, inflammation, and stress hormones related to the M. charantia extract consumption would be needed.

Fracture Mechanics Analysis of the Weldment in Pulley for Belt Conveyor (컨베이어용 풀리의 용접부위에 관한 파괴역학 설계기술 개발)

  • Han, Seung-U;Lee, Hak-Ju;U, Chang-Su;Lee, Sang-Rok
    • 연구논문집
    • /
    • s.23
    • /
    • pp.127-140
    • /
    • 1993
  • The drive pulley, which is employed for loading and unloading raw materials in a steel mill, is usually manufactured by use of various welding processes. In this study the weldment in the pulley, in which TIG and $CO_2$ welding processes are used, has been analyzed from view point of fracture mechanics. Fracture toughness tests have been performed according to ASTM E813. A servo-hydraulic testing machine (10kN) has been employed. Also the crack propagation tests (Mode I) have been performed with compact tension specimen in compliance with ASTM E647. To predict the critical crack size in the weldment, finite element stress analysis for the drive pulley under real operating conditions have been performed. In addition, the residual stresses at the weldment and in heat-affected zone have been obtained by hole drilling method. The planar critical crack size have been predicted for the drive pulley by considering the stress analysis results and the residual stresses due to welding process. For the drive pulley considered in this study, it has been concluded that the most important factor in determining the critical crack size is the welding residual stress in the transverse direction. Also the effect of stress concentration at the root of the weldment have been noticeable. For the planar crack, the fatigue crack growth life from an initial crack size of 2mm to the critical crack size obtained as in the above have been predicted. The predicted lives were between 55, 900 and 72, 000 cycles depending on the shape of the elliptical crack. The predicted lives were in fairly good agreement for the drive pulley considered in this study.

  • PDF

A Study on Evaluation of Thermal Environment using Heat Stress Indices for Deep Coal Mine in Korea (열적지표를 적용한 국내 고심도 석탄광산의 열환경 평가 연구)

  • Park, Seon-Oh;Roh, Jang-Hoon;Kim, Jin
    • Tunnel and Underground Space
    • /
    • v.24 no.2
    • /
    • pp.166-175
    • /
    • 2014
  • In this study, the thermal environment in a large scale coal mine located in Taebaek, Gangwondo was assessed by a field survey. In order to estimate the thermal environment, various heat stress indices such as WBGT, HSI, ESI, KATA index and effective temperature were investigated. Correlation analysis was also conducted. It was found that the thermal environment in most workplace was high. In particular, the correlation coefficient between HSI reflected in physiological fatigue characteristic and the maximum sweat evaporation heat was -0.834. This shows that the correlation coefficient have the most influence on HSI index. The factor which has the most influence on the maximum sweat evaporation heat is velocity of air. The thermal environment of high-depth coal mines is likely to be improved by installing a structure that enables the maximum prevention of extended digging, air doors, or the leakage of the inflow of air in the first shaft.

The Relationship Between Stress and Stress Symptoms among Elementary School Students (초등학생의 스트레스와 스트레스 증상간의 관계)

  • So, Hyun;Chung, Young-Sook
    • Journal of the Korean Society of School Health
    • /
    • v.16 no.1
    • /
    • pp.91-104
    • /
    • 2003
  • The purpose of this study is primarily intended to examine the stress and physical, emotional and behavioral stress symptoms of elementary school students supply the basic data of intervention for children's health promotion. The subjects of this study were 616 students who were currently enrolled in 5th and 6th grade elementary school in Jeollabukdo ; 3 schools in J city and other 6 in 3 rural area. The data were collected by self-reported questionnaire from 3rd to 13th April 2002 and collected data were analyzed by SPSS WIN 8.0. The results of this study were as followings. 1. The mean score of stress that children experience was 2.73 and the most stressful factor was a friendship stress. The most frequently experienced stress were feel that a friends would leave them alone. 2. The mean score of stress symptom that children experience was 1.92 and the most stressful symptom was the emotion symptom. The most frequently experienced stressful symptom were feel fatigue of everyday. 3. General characteristics related to stress were showed significantly different according to sex(t=-3.243, p=.001) 4. General characteristics related to stress symptoms were showed significantly different according to sex(t=-2.268, p=.024), family circumstances(F=8.697, p=.000), academic scores(F=11.216, p=.000) and parental concerns on a child(t=-2.561, p=.011). 5. The relation between stress and stress symptoms showed a positive correlation, which was significant statistically(r=.453, p=.000). In conclusion, elementary school students experience various stresses and the stress symptoms have positive close connection with health problems. Therefore, to study the students stress and consequent symptoms further, it is recommended that we should subdivide and analyze the stressor and stress symptoms by proper areas. In the meantime, in order to promote children's health using the data in this study, we should develop the correlated program among individual, family, school and community while we are deeply concerned about and support children continuously.

Physical Health Status and Depression of a Community-Dwelling Elderly Group (일부 지역사회 노인의 신체건강 상태와 우울)

  • Kim, Nam-Cho;Yang, Soo
    • Journal of Korean Academy of Nursing
    • /
    • v.31 no.6
    • /
    • pp.1012-1020
    • /
    • 2001
  • The purpose of this study was to describe physical health and depression status, as well as to assessing factors that influence the physical health status. Method: The data was collected from July to August 2000. Study participants were 252 community-dwelling elderly who were recruited from 10 senior centers located in Seoul, Korea. Their physical health status was measured using the Physical Health Status Measurement Scale developed by Choi and Jung (1991), and depression was measured using BDI-II developed by Beck et al. (1996). Results: 1) The physical health status score was 4.00 $\pm$0.68 (range :1- 5). The sub-dimension that showed the highest score was personal hygiene ability at 4.62$\pm$0.95, and the lowest score was sexual function at 2.20$\pm$1.38. 2. The depression score was 17.99+9.79 (range : 0-63). Regarding the sub-dimensions, the depression scores were higher in the domain of interest with sexuality, general weakness, difficulty in concentration, and fatigue. 3. Deeper levels of depression were correlated with a declining physical health status. 4. The most influential factor on physical health was depression, and the explaining variance was 31.68%. Conclusion: It is concluded that elder subjects in senior centers had fairly good physical health and self-care ability. Also, they did not have significantly high levels of depression. Therefor, health promotion of elderly, it is recommended that elder individuals should be regarded as a respectful and useful segment of our society. Along with this basic concept, there should be a social milieu that does not snow prejudice. Moreover, health care professionals should give more attention to helping the elderly achieve a minimal level of ALD, and, particularly, to raise sexuality and help energize the lives of elder individuals.

  • PDF