• Title/Summary/Keyword: Life Condition

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Fatigue Life Assessment of Journal Box Attached to Bogie under Multiaxial Random Dynamic Loading (다축 Random Dynamic 하중을 받는 대차 저널박스의 피로수명평가)

  • Park, Sang-Goo;Kim, Seung-Seob;Han, Sung-Wook;Park, Geun-Su;Woo, Kwan-Je
    • Proceedings of the KSR Conference
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    • 2009.05a
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    • pp.1125-1131
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    • 2009
  • This paper presents the evaluation of fatigue life for a journal box attached to rolling stock bogie under random dynamic loading condition. Because a journal box was under random dynamic loading conditions, the fatigue life assessment due to these loads requires the analysis considering the multiaxial effect of random dynamic loading. To do this work, the finite element analysis has been conducted to calculate random dynamic response using multiaxial acceleration data. Then, the fatigue life assessment of component has been conducted using vibration fatigue analysis applying the power spectral densities of the responses obtained through the FEA The results of fatigue life assessment were compared to the damage from the strain measurement. This study shows that can be evaluated the fatigue life assessment considering real service condition about a component attached to rolling stock bogie.

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Strengthening Performance of Aged Papers with Chemical Strengthening Treatments (화학적 보강 방법에 따른 열화 종이의 보강 특성)

  • Lee, Hyeyoon;Lee, Jegon;Kim, Minsu;Sim, Kyujeong;Youn, Hye Jung
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.46 no.5
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    • pp.35-42
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    • 2014
  • Many historical archives have been deteriorated by aging with time. Various kinds of defects such as worm-hole, yellowing, brittleness are observed and their severity was dependent on raw material type, storage condition, and so on. For a long-term use and storage, a proper preservation treatment is required. Many studies on preservation and conservation have been carried out on hanji which was made from mulberry fiber, but there are few concerns on foreign paper. Therefore, aging and chemical strengthening treatment was done on paper made of bamboo and wood fibers depending on aging condition, the type and pickup weight of chemicals and treatment method. When methyl cellulose was treated with impregnation or brushing, the aged paper was strengthened effectively. The strengthening effect by chemicals was dependent on the aged condition of the paper.

Optimal Designs of Partially Accelerated Life Tests for Weibull Distributions (와이블 분포에서 부분가속수명시험의 최적설계)

  • Chung, Sang-Wook;Bai, Do-Sun
    • Journal of Korean Institute of Industrial Engineers
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    • v.24 no.3
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    • pp.367-379
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    • 1998
  • This paper considers two modes of partially accelerated life tests for items having Weibull lifetime distributions. In a use-to-acclerated mode each item is first run at use condition and, if it does not fail for a specified time, then it is run at accelerated condition until a predetermined censoring time. In an accelerated-to-use mode each one is first run at accelerated condition and, if it does not fail for a specified time, then it is run at use condition. Maximum likelihood estimators of the parameters of the lifetime distribution at use condition, and the 'acceleration factor' are obtained. The stress change time for each mode is determined to minimize the asymptotic variance of the acceleration factor, and the two modes are compared. For selected values of the design parameters the optimum plans are obtained, and the effects of the incorrect pre-estimates of the design parameters are investigated. Minimizing the generalized asymptotic variance of the estimators of the model parameters is also considered as an optimality criterion.

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Investigation of Job satisfaction, Organizational commitment and Factors of continuing work life for Nano-convergence employees

  • Lee, Hongki;Myoung, Sungmin
    • Journal of the Korea Society of Computer and Information
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    • v.24 no.6
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    • pp.151-158
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    • 2019
  • In this paper, we analyzed the relationship between employment stability, wage level, welfare system, working condition, job satisfaction and organizational commitment in order to find out ways to develop and competitiveness of the nano-convergence industries. Through this study, we conducted the possibility of deriving organizational commitment by job satisfaction which is given through employment stability, wage level, welfare system, and working condition for continuing their work life. In order to find relationships between each concepts, we used a multiple regression analysis with job satisfaction and commitment as dependent variable and employment stability, wage level, welfare system, and working condition as independent variables. Through this study, it was expected to increase the organizational commitment through the job satisfaction of the employees if a changing method of employees management is centered on some tasks suggested for the sound working condition and efficient utilization policies.

A Study on Influential Factors Related to the Level of life Satisfaction of the Elderly Residents at Paid Facilities (유료시설 거주노인의 생활만족도 영향요인)

  • 서병숙
    • Journal of Families and Better Life
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    • v.14 no.4
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    • pp.129-144
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    • 1996
  • The purpose of this study was to illuminate the ways to im-prove the level of life satisfaction of the elderly who chose or happened to live at paid facilities by examining some of factors such as individual family social support and facility related el-ements that would influence their life satisfaction. The interview outcomes came out in three main discussions. First the general characteristics of the participating elderly appeared to be that most of them were ver7y elderly relatively highly educated females and religions and the rate of being ill was high. And a half of them considered themselves as heal- thy people and the other half as unhealthy. Secondly in view of statisticsal results the level of their life satisfaction was influnced by their individual family and facillity related factors. As far as their individual related factor are concerned the level of one party's life satisfaction was relative-ely higher than that of other's when the person is female had religio presumed oneself as in healthy and good physical condition. And when participating member keeps good relation-ship with his or her own children the level of the person's life satisfaction was only slightly higher than other elderly group who did not have good relationship with their children. There were no other significant statistical differences on the level of their life satisfaction related to the social support factors between those two group. Thirdly the level of the elderly's life satisfaction was influe- nced in the order of folldwing factors: (1) the quality of facility living condition 2) the commitment of ownership of the organization (3) the elderly residents' own education level (4) the elderly's own subjectivel health condition and (5) the sex of the individuals.

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The Effect of Product Experience Through Virtual Reality on Product Evaluation

  • Jeon, Eunmi;Han, Youngjee;Woo, Hyunjin
    • Asia Marketing Journal
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    • v.21 no.4
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    • pp.45-57
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    • 2020
  • With the development of new technologies, virtual reality (VR) is emerging as a new consumer marketing platform. Yet, only a few studies have investigated VR in the consumption context. The current research explores how experiencing a product through VR influences consumer attitude and purchase intention for the product. Although assessing products in real life is believed to be more diagnostic than that through VR, the present research revealed that experiencing a product through VR could lead to a more positive attitude toward and higher purchase intention for the product. We also demonstrated that "enjoyment" has a mediating effect while evaluating the product through VR. To compare product experience through VR to that in real life, we employed the HTC Vive VR system to implement a VR environment. In the VR condition, participants evaluated plastic building blocks using a VR headset and a motion controller; and in the real life (reality) condition, they evaluted plastic building blocks printed using a 3D printer to make them look exactly the same as the blocks used in the VR condition. Finally, implications and suggestions are discussed.

A Study on the Depression and Anxiety of High School Students in an Urban Area (도시지역 일부 고등학생들의 우울과 불안에 관한 조사 연구)

  • 곽은주;송인순;정용준;조영채
    • Korean Journal of Health Education and Promotion
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    • v.20 no.2
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    • pp.63-79
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    • 2003
  • This study has examined the degree of depression and anxiety among high school students in an urban area and then explored the factors influencing their depression and/or anxiety status. Self-administered questionnaires were offered to 2,381 students from ten high schools in Daejon Metropolitan City. The items for investigation included such factors as various characteristics of school and family life, daily life style, and the degree of depression and anxiety. Based on the study results, the following conclusions were made; 1. The distribution according to the depression degree has shown that 61.9% of students were normal, 32.9% of students had mild depression, 5.0% moderate depression, and 0.3% severe depression. As for anxiety, 40.2% of students were normal, while 19.1% were classified as having anxiety and 40.7% borderline anxiety. 2. As regards to the degree of depression and anxiety, it was greater in girls than boys, in 3rd graders than 1st and 2nd graders, and in the groups who have recieved lower grades in studies, who had poor relations with their friends and a low feeling of satisfaction with school life. In particular, concerning various characteristics of family life, the scores of depression and anxiety were higher in the groups whose financial conditions were poor, whose parents' interests were lower, whose degree of satisfaction with their family and school life was lower, than their counterparts. 3. According to their life styles higher scores of depression and anxiety were found in the groups whose sleeping time was inappropriate, whose breakfasts were skipped, who ate daily snacks, who didn't take regular exercises, and who had poor health habits, compared to their counterparts, respectively. 4. As for the correlation between the degree of depression and its associated variables, the higher scores of depression were in positive correlation with the groups who had lower grades in studies, poor relation with their friends, low feeling of satisfaction with school and home life, low parents' interest, poor subjective condition of health, breakfast skipping, lack of regular exercises, and lower indices of health habits. 5. As for anxiety, the higher scores of anxiety were in the positive correlation with the groups with poor relation with their friends, low feeling of satisfaction with school and family life, poor subjective condition of health, lack of regular exercises, and poor health habits. 6. The influential factors on the depression of students were selected such as subjective condition of health, sex, feeling of satisfaction with family and school life, grades in studies, relation with their friends, presence of regular exercises, degree of interest of parents, sleeping time, cigarette smoking and eating breakfast. 7. The influential factors on the anxiety state of students were selected such as subjective condition of health, feeling of satisfaction with family and school life, sex, sleeping time, regular exercises, cigarette smoking, snacking and relations with their friends. The present study results suggest that girls rather than boys, higher graders than lower ones are more vulnerable to anxiety and depression state, and besides, various characteristics of school and family life, and daily life style can be influential on students' emotional states. Therefore, better management of psychological status of students is thought to require a wide variety of measures to modify the influencing factors and to encourage social support.

Effects of Citrus Flavonoids on the Lipid Peroxidation Contents (감귤류 플라보노이드가 지질 과산화물 함량에 미치는 영향)

  • Cha, Jae-Young;Kim, Hyun-Jeong;Kim, Sung-Kyu;Lee, Yong-Jae;Cho, Young-Su
    • Food Science and Preservation
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    • v.7 no.2
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    • pp.211-217
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    • 2000
  • The effects of Citrus flavonoids, hesperetin, hesderidin, naringenin, and naringin, on nonenzymatic lipid peroxidation were studied in three different in vitro experimental models. Hesperetin showed the most antioxidant effect in this experimental condition by measuring the malondialdehyde production using the thiobarbiturate and thiocyanate methods, the lipid peroxidation of microsomal membranes, and DPPH (${\alpha},{\alpha}'-diphenyl-{\beta}-picrylhydrazyl$) method. The antioxidative activity of the flavonoid aglycone forms, hesperetin, Citrus aglycone flavonoid, suggest the most antioxidant effect in this experimental condition, and this effect indicate more potent in the aglycones than their corresponding glycosides.

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