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Prediction of Post-Deformation for Plastic Component Considering Residual Stress and Viscoelasticity (판류응력 및 점탄성을 고려한 플라스틱 부품의 후면형 예측)

  • Moon, H.I.;Kim, H.Y.;Choi, C.W.;Jeong, K.S.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2008.10a
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    • pp.341-344
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    • 2008
  • Plastics is commonly used in consumer electronics because of it is high strength per unit mass and good productivity. But. using, transporting, and keeping of plastic component was happened post-deformation. As time goes by and temperature is changed, the post-deformation causes the problems of exterior design and performance. But, it is difficult to estimate the post-deformation by only thermal deformation analysis. Also, the estimation technique of the pest-deformation must be easily applied to product development and it should be reliable because development time of product is limited. In the paper. the process to predict the post deformation under cyclic thermal loadings was suggested. The process was applied to the real panel, and the deformation predicted by the analysis was compared with that of real test, which showed the possibility of applying the suggested process to predict the post deformation of plastic product under thermal loadings.

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A Study on the Intention of Smoking Cessation Behavior and it's Determinants - Based on the Theory of Planned Behavior- (일부 대학생의 금연의도 및 의도결정요인에 관한 연구 - 계획된 행위이론(Theory of Planned Behavior)에 기초하여 -)

  • Hyun, Hye Jin
    • Journal of the Korean Society of School Health
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    • v.11 no.2
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    • pp.217-228
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    • 1998
  • This study was conducted to investigate determinants of intention of smoking cessation behavior. We sampled 204 university student smokers using questionaires and analyzed the data using the t-test, ANOVA, Pearson product-moment correlation, and multiple regression. The results are as follows: 1. The attitudes concerning smoking cessation behavior are related to a student's course of study, religion and is further related to whether or not they tried to stop smoking. The subjective norm is related to smoking cessation recommendations. Perceived behavioral control is related to a growth criterion, the smoking amount and whether or not they have tried to stop smoking. The intention of smoking cessation behavior is related to smoking amount and whether or not they nare tried to stop smoking. 2. Total symptom number is related to smoking amount and smoking period. 3. Total symptom number is related to behavioral belief, attitude, and the intention to stop smoking. In conclusion, it was found that university students smoke far too much, however the intention to stop smoking is very low. Therefore, an intention promoting program of smoking cessation behavior is needed to reduce the smoking rate and relaxation therapy is necessary for in changing health promoting habits.

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Development f head-neck complex dummy for experimental study (실험적 해석을 위한 머리-목 형태의 더미 개발)

  • Kim, Yeong-Eun;Nam, Dae-Hun;Koh, Chang-Hun
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.21 no.7
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    • pp.1058-1072
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    • 1997
  • A head-neck complex dummy, for measuring brain pressure and reaction force in the cervical spine was developed for experimental study related in injury mechanism. Dummy comprised aluminium-casted head with water filled cavity for simulating brain and mechanical neck assembled with six motion segments. Several kinds of experiments (compression, bending, cyclic modulus, relaxation and constant velocity profile) for the developed mechanical neck showed that this neck model is biomechanically reliable compared with in-vitro test results. As an application of developed head-neck complex dummy, shock absorbing properties of protective helmet was chosen. The experiments showed that the maximum pressure increment of brain after impact was tolerable compared with the guide line for mild brain injury pressure (25psi). Constrast to this results, the reaction force in the neck was high enough to produce failure in the cervical spine.

Effects of a Short-term Home-based Pulmonary Rehabilitation Program in Patients with Chronic Lung Disease (만성폐질환자를 위한 가정 호흡재활 단기 프로그램의 효과)

  • 오의금;김순희;박희옥;방소연;이춘화;김소희
    • Journal of Korean Academy of Nursing
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    • v.33 no.5
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    • pp.570-579
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    • 2003
  • Purpose: The purpose of this study is to exam the effects of a short-term pulmonary program on lung function, exercise tolerance, and quality of life in chronic lung patients. Method: Randomized controlled pre-post test design was used. The outcome measures were forced expiratory volume in one second (FEV1, % predicted), 6 min walking distance (6MWD), Borg score after 6MWD, and Chronic Respiratory Disease Questionnaire (CRDQ). Experimental group performed the 4-week home-based pulmonary rehabilitation program composed of inspiratory muscle training, upper and lower extremity exercise, relaxation, and telephone visit. Patients in control group were only given education about self-management strategies. Thirty four patients with moderate-to-severe respiratory impairment were recruited, and 28 patients (19 in experiments, 15 in control) completed the study. Result: Significant improvements in lung function, exercise tolerance, and health related quality of life were found only in the experiment group. Conclusion: This study yielded evidence for the potential and beneficial effects of home-based pulmonary rehabilitation program in patients with moderate to severe chronic lung disease. The program could be adequately utilized for improvement of health related quality of life in chronic lung patients.

Influence of Endurance tests on Space Charge Distribution of 160kV HVDC XLPE Cable

  • Liu, Yun-Peng;Liu, He-Chen
    • Journal of Electrical Engineering and Technology
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    • v.12 no.1
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    • pp.302-309
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    • 2017
  • The ageing of XLPE cable insulation will lead to the accelerating accumulation of space charge, which will greatly affect the safe operation of the HVDC cable. In order to investigate the influence of different ageing modes on the space charge distribution of the HVDC cable, thermal stressed, electrical stressed and electro-thermal stressed endurance tests were carried out on the XLPE peelings. The tested XLPE peelings were obtained from 160kV HVDC cable insulation. The endurance tests were carried at thermal stress of 363K, electrical stress of 20kV/mm DC and a combination of both. The Pulsed Electro-Acoustic (PEA) method was used to measure the space charge distribution of the samples. The influences of ageing on the trap energy distribution were analyzed based on the isothermal relaxation theory and the decay characteristics of the space charge. The results showed that thermal ageing would help to improve the crystalline morphologies of the XLPE at the early stage. The total amount of space charge decreased compared to the ones before thermal ageing. The long term of electrical stress would result in the cleavage of polymer molecule chains which would intensify the accumulation of space charge and increase the density and depth of electron traps. With a combination of electrical and thermal stress, the injection and migration of space charge were more significant. Besides, the depth and density of electron traps increased rapidly with the increase of endurance time.

Psychological Relaxation Effects of User Based upon the Types of Rooftop Garden (옥상녹화 시공 유형이 이용자의 심리적 변화에 미치는 영향)

  • Kim, Jeong-Ho;Yang, Ji;Yoon, Yong-Han
    • Journal of Environmental Science International
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    • v.22 no.4
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    • pp.435-442
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    • 2013
  • The purpose of this study, the type of rooftop learn more about the psychological benefits to users has been carried out, and healthy college students were examined in 40 patients. Conduct research to make the rooftop of the type of lawn, trees, ecological garden, wetland biotope, flowering plant in Seoul were divided into six groups. Measurement methods based on the type designation of the Planting and landscape photography by once the participants for each 10 minutes to watch and mood state tests (POMS) and the mean fractionation (SD), based on survey information about the psychological effects were correlated. Mood States test lawn, tree-oriented type, flowering plant stability in type, kindness, openness, and the effect of raising warme there was a tension, anxiety, depression, anger inhibition was effective. In contrast, depression and fatigue are common rooftop greening, respectively. The results in terms of the psychological effects of the type of rooftop garden ecology and wetland biotope than lawn, tree-oriented type, flowering plant types of users with a positive psychological effect seemed to be better.

A Meta-Analysis of Effects of Job Stress Management Interventions (SMIs) (직무스트레스관리중재 효과에 대한 메타분석)

  • Kim, Jeong-Hee
    • Journal of Korean Academy of Nursing
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    • v.37 no.4
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    • pp.529-539
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    • 2007
  • Purpose: This quantitative meta analysis sought to determine the effectiveness of SMIs. Method: Forty-six experimental studies with a randomized or nonequivalent control group pre-post test design were included in the analysis. The selected studies were classified according to the sample characteristics, the types and methods of the interventions, and the types of outcome variables. Six intervention types were distinguished: cognitive-behavioral intervention(CBT), relaxation techniques(RT), exercise(EX), multimodal programs 1 and 2(MT1, 2), and organization-focused interventions(OTs). Effect sizes were calculated for the 4 outcome categories across intervention types: psycho-social outcome, behavioral-personal resources, physiologic, and organizational outcome. Results : Individual worker-focused interventions(ITs) were more effective than OTs. A small but significant overall effect was found A moderate effect was found for RT, and small effects were found for other ITs, The effect size for OTs was the smallest. The interventions involving CBT and RT appeared to be the preferred means of reducing worker's psycho-social and organizational outcomes. With regard to physiologic outcomes, RT appeared to be most effective. CBT appeared to be most effective in reducing psycho-social outcomes. The effects of OT were non-significant, except for the psycho-social outcomes. Conclusions: SMIs are effective. Interventions involving RT and CBT are more effective than other types.

Butt 용접부에서 잔류응력이 피로균열성장거동에 미치는 영향에 대한 실험적 연구 1

  • 최용식;김영진;우흥식
    • Journal of Welding and Joining
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    • v.6 no.4
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    • pp.27-34
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    • 1988
  • The objective of this paper is to investigate the effect of residual stress on fatigue crack growth behavior. For this purpose, submerged arc welding was performed on SM50A steel plate and post weld heta treatment (PWHT) was followed. Residual stress distribution on the weld plate was determined by a hole drilling method and a series of .DELTA.P-const. and .DELTA.K-decreasing fatigue test were performed on the three different regions, i.e. weld metal, HAZ and base metla. Following conclusins were achieved. 1. In "as welded" specimens, tensile residual stresses were produced in the center portion of the specimen while compressive residual stresses were produced near the edges. In PWHT specimens, however, most of the residual stresses were disappeared. 2. The fatigue crack growth behavior in low .DELTA.K region was considerably affected by the presence of residual stress in both "as welded" and PWHT specimens. 3. Because of the relaxation of residual stresses in PWHT condition, the values of m increased from 2.62-2.78 (in the "as welded" condition) to 3.57-3.91 (in the "PWHT" condition)3.91 (in the "PWHT" condition)condition)

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One Case Report of Somatoform Disorder Patient with Dyspnea, Dysarthria and Gait Disturbance (호흡곤란, 구음장애, 보행장애 증상을 보인 신체형 장애 환자 치료 1례 보고)

  • Kim, Ja-Young;Seo, Joo-Hee;Kang, Hyun-Sun;Sung, Woo-Young;Jeong, Da-Un
    • Journal of Oriental Neuropsychiatry
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    • v.18 no.3
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    • pp.237-247
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    • 2007
  • People with somatoform disorder have a number of different symptoms that typically last for several years. Their symptoms can't be traced to a specific physical cause. In people with somatoform disorder, medical test results are either normal or don't explain the person's symptoms. The symptoms of somatoform disorder are similar to the symptoms of other illnesses. People with this disorder may have several medical evaluations and tests to be sure that they don't have another illness. In this case, we described a 56-year old man who was diagnosed as R/O) ALS, because he has many similar symptoms of ALS (amyotrophic lateral sclerosis) such as gait disturbance, dysarthria, dyspnea. But we diagnosed his case as somatoform disorder and treated with herbal medication, acupuncure treatment ,negative cupping and relaxation training. Through these treatment, the patient showed improvement of chief complains and accessory symptoms.

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Effects of defence holes on notched strength and fatigue properties in plain woven composite (평직복합재의 노치강도 및 피로특성에 미치는 보조원공의 영향)

  • Kim, Jung-Kyu;Shim, Dong-Suk;Han, Min-Gyu
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.21 no.11
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    • pp.1965-1971
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    • 1997
  • The relaxation of stress concentration in notched members can be very significant in the improvement of notched strength and fatigue life. This paper investigated the relationship of stress concentration factor, and notched strength and fatigue life. The stress concentration factors were analyzed by FEM. Uniaxial tensile and fatigue tests were carried on plain woven composite specimens which have a main hole and two defence holes. From experimental results, the notched strength and the fatigue limit increased up to about 50% and 30% respectively due to the reduction in stress concentration. The fatigue lives predicted by Juvinall's approach were underestimated than test results and this trends were remarkable as nothed strength increased. This is because of the underestimation of a coefficient. A in S-N curve (.sigma.$_{ar}$ =A $N_{f}$ $^{B}$). Therefore, considering notched strength the coefficient A was modified. The fatigue lives by this process were agreed well with the experimental results.sults.