• Title/Summary/Keyword: mean life

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Estimation of Mean Life and Reliability of Highway Pavement Based on Reliability Theory (신뢰성 개념을 이용한 포장의 평균수명 및 신뢰도 예측)

  • Do, Myung-Sik
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.30 no.5D
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    • pp.497-504
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    • 2010
  • In this paper, the author presents a reliability estimation technique to analyze the effects of traffic loads on pavement mean life based on the national highway database of Suwon and Uijeongbu region from 1999 to 2008. The estimation of the mean life, its standard deviation and reliability for pavement sections are calculated by using an appropriate distribution, Lognormal distribution, based on reliability theory. Furthermore, the probability paper method and Maximum likelihood estimation are both used to estimate parameters. The author found that mean life of newly constructed sections and over-layed sections is about 6.5 to 7.9 years and 7.3 to 9.1 years, respectively. The author also ascertained that the results of cumulative failure probability for pavement life between the proposed methods and observed data are similar. Such an assessment methodology and measures based on reliability theory can provide useful information for maintenance plans in pavement management systems as long as additional life data on pavement sections are accumulated.

Mean Life Assessment and Prediction of the Failure Probability of Combustion Turbine Generating Unit with Data Analytic Method Based on Aging Failure Data (통계적 분석방법을 이용한 복합화력 발전설비의 평균수명 계산 및 고장확률 예측)

  • Lee, Sung-Hoon;Lee, Seung-Hyuk;Kim, Jin-O
    • The Transactions of the Korean Institute of Electrical Engineers A
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    • v.54 no.10
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    • pp.480-486
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    • 2005
  • This paper proposes a method to consider an aging failure probability and survival probability of power system components, though only aging failure probability has been considered in existing mean life calculation. The estimates of the mean and its standard deviation is calculated by using Weibull distribution, and each estimated parameters is obtained from Data Analytic Method (Type H Censoring). The parameter estimation using Data Analytic Method is simpler and faster than the traditional calculation method using gradient descent algorithm. This paper shows calculation procedure of the mean life and its standard deviation by the proposed method and illustrates that the estimated results are close enough to real historical data of combustion turbine generating units in Korean systems. Also, this paper shows the calculation procedures of a probabilistic failure prediction through a stochastic data analysis. Consequently, the proposed methods would be likely to permit that the new deregulated environment forces utilities to reduce overall costs while maintaining an are-related reliability index.

A Study of the Relation between Quality of Life and Family Burden of Home-based Hospice Patient Families (재가 호스피스환자 가족의 삶의 질과 가족부담과의 관계)

  • Lee, Eun-Ju;Kim, Hyang-Dong
    • Korean Journal of Hospice Care
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    • v.6 no.2
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    • pp.69-78
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    • 2006
  • Purpose: This study was conducted to analysis relationship about quality of life and family burden of the home-based hospice patient families. Method: The subjects consisted of 94 families with home-based hospice patient. The ages of the subjects were 17-73 years with hospice patient who receivedhome visiting care and registered at 4 hospitals in Daegu and Kyung-Buk. The data was collected from March to November 2004. The instruments used for the study were Quality of Life Scale (GLS) and Family Burden Questionnaire (FBQ). The analysis was done using frequency, mean, standard deviation, correlation and stepwise multiple regression with SPSS WIN 11.0. Results: The results were as follows: 1. The mean score of family burden was 3.36 ($\pm0.55$). The highest mean score of family burden 6 factors were wellness of future 3.85($\pm1.10$), and the second was economic family burden 3.63($\pm0.97$). 2. The mean score of quality of life was 3.09 ($\pm0.48$). The lowest score of quality of life 6 factors were economic status 2.86($\pm0.54$), and the second was physical state and function 3.01($\pm0.62$). 3. In the home-based hospice patient families, family burden had significant negative correlation with quality of life(r=-0.25, p=0.012). 4. Emotional status accounted for 11% of family burden in the home-based hospice patient families by means of stepwise multiple regression. 5. Economical status accounted for 18 and age accounted for an additional 11% of quality of life in the home-based hospice patient families by means of stepwise multiple regression. Conclusion: The finding showed that family burden and quality of life of home-based hospice patient families were significantly negative correlation and the highest factor of family burden was wellness of future and the most important factor of quality of life was economic status.

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Determination of Total Phenol Content and Selected Phenolic Metabolites Analysis of Rice (Oryza sativa L.) Genetic Resources

  • Md Faruk Ahmed;Hee-Sung Moon;Yun-Ju Kim;Seung-Hyun Kim;Ill-Min Chung
    • Proceedings of the Korean Society of Crop Science Conference
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    • 2021.04a
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    • pp.137-137
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    • 2021
  • The study of total phenol (TP) content from 700 rice varieties was evaluated using the UV-Vis spectrophotometric method. The calibration curve of serial diluted gallic acid as a standard of this study showed the acceptable performances (R2 = 0.999, mean accuracy 90%) and the mean of % relative standard deviation (%RSD: 0.07%) within the range of 7.8 to 1000 ppm concentrations. The mean value of total phenol content from 700 rice varieties was 2723.15 ㎍/g ranged from 55.48 ㎍/g to 9922.23 ㎍/g and the mean %RSD was 2.5%. Furthermore, this study aim was to analyze and profile individual phenolic compounds in the rice genetic resources to construct an integrative database for development of new rice variety with high functionality for health and understanding of phenolics characteristics in the rice grain. Herein, we analyzed selected 100 rice varieties based on high TP content and identified total 15 phenolic compounds by LC-ESI-MS/MS. Among selected 100 rice genetic resources, the phenolic metabolites consisted of higher amount of flavonoid (catechin) and phenolic acid mainly protocatechuic acid. Further research of more selected rice genetic resources would be continued to provide for an integrative phenolics profile of different rice genetic resources.

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A Study Burden, Social Support and Quality of Life in Mothers of a Child with Nephrotic Syndrome (신증후군 환아 어머니의 부담감, 사회적 지지 및 삶의 질)

  • 성미혜
    • Journal of Korean Academy of Nursing
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    • v.30 no.3
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    • pp.670-681
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    • 2000
  • The purpose of this study was to identity the level of burden, social support and quality of life of the subjects. The subjects of this study were 68 mothers of nephrotic syndrome patients whose children were hospitalized in one pediatric ward of the University Hospital in Seoul. The data was collected using questionnaires, and the period of the data collection was from Nov. 15 to Dec. 31, 1999. The instruments used for this study were the Burden Measurement Instrument developed by Montgomery et. al(1985), social support measurement instrument designed Brandt an Weinert(1978) and Quality of life scale designed by Ro,Yoo JA(1988). The data analysis was done by SPSS, t-test, ANOVA and the Pearson correlation coefficient. The results of were as follows. 1. The level of burden showed a mean score of 54.47, the level of social support, a mean score of 86.00 and the level quality of life, a mean score of 140.20. 2. The level of burden differed according to mother's religion, patient's purpose for admission and perceived patient's condition by mothers. 3. The level of social support and the level of quality of life differed according to perceived patient's condition by mothers. 4. There was a negative correlation between burden and social support(r=-.348, p<.001). Also, burden was negatively related with quality of life(r=-3.97, p<.001). Social support was positively related with quality of life(r=.064, p<.001).

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Correlations among Total Symptom Distress, Uncertainty and Quality of Life among Women With Endometriosis (자궁내막증을 가진 여성의 증상 스트레스, 불확실성, 삶의 질 관계 연구)

  • Choi, So-Young;Jun, Eun-Mi;Ahn, Suk-Hee;Seo, Young-Seung
    • Women's Health Nursing
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    • v.11 no.4
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    • pp.316-323
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    • 2005
  • Purpose: The purpose of this study was to explore the relationships among women's total symptom distress, uncertainty and quality of life in women with endometriosis. Method: A total of 121 women who had been diagnosed with endometriosis was given a questionnaire. Data was collected from August 2004 to January 2005. The data was analyzed by frequency, mean, t-test, ANOVA, Pearson correlation coefficient, and multiple linear regression analysis using SPSS WIN 10.0 software. Result: The mean score of TSD was 3.23. 'Menstrual cramping' showed the highest score. The mean score of uncertainty, and quality of life of the subject was 56.6, and 38.3 respectively. TSD was significantly related with coffee intake and uncertainty was significantly related with marital status, economic status, alcohol intake, diagnosis after period, and family history. Quality of life was significantly related with age, and dysmenorrhea. There were significant relationships between total symptom distress and uncertainty, and quality of life. There were significant relationship between uncertainty and quality of life. Conclusion: Endometriosis symptoms showed a significant relationship with uncertainty and quality of life. This study will help to manage women with endometriosis.

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A Study on the Correlation between Stress, Mother-adolescent Communication and Quality of Life in the Adolescents (청소년의 스트레스ㆍ어머니-자녀 의사소통과 삶의 질간의 관계)

  • Song Mi-Ryeong;Ahn Hye-Young;Kim Eun-Kyung
    • Child Health Nursing Research
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    • v.8 no.2
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    • pp.141-151
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    • 2002
  • The purpose of this study was to find out the correlations between mother-adolescent communication and quality of life in the adolescents. The study subjects consisted of 171 adolescents who were going to middle school and high school. The data included general characteristics, health related characteristics, stress, mother-adolescent communication and quality of life. The data were analyzed by frequency, mean, percentage, t-test, ANOVA and Pearson's correlation using the SPSS statistical program. The result were as follows: 1. The mean score for the stress of adolescent was 2.48(maximum score: 5) and there were significant difference according to demographic variables that is sex, grade, father's being and health related variables that is health status, frequently ill, illness severity and illness of family. 2. The mean score for the mother-adolescent communication was 3.27(maximum score : 5) and there were significant difference according to demographic variables that is father's and mother's being. There were no significant difference according to any health related variables. 3. The mean score for the quality of life of adolescent was 3.97(maximum score : 7) and there were no significant difference according to demographic and health related variables. 4. There was a negative correlation between the stress and the quality of life. There was a positive correlation between the quality of life and the mother-adolescent communication. There was a no correlation between the mother-adolescent communication and the quality of life. Consequently, the implication for nursing of this study is that there is a need to develop relief strategy of stress for the female adolescents. And there is a need to develop a promoting program of quality of life for the adolescents considering the stress and the mother-adolescent communication.

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A Study on the Correlation among Family Life Events Stress, Family Functioning and Social Support of the Wives who Reside in Some Area (일 지역 주부의 가족 생활사건 스트레스, 가족기능 및 사회적 지지의 관계)

  • Kwon, Su-Ja
    • Research in Community and Public Health Nursing
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    • v.12 no.3
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    • pp.696-704
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    • 2001
  • Purpose: This study was to investigate the family life events stress and family functioning and social support of wives, and to find out the correlation among these variables. Method: The subjects were 263 wives who participated voluntarily in the questionnaire. The instrument used in this study comprised family life events stress, family functioning and social support instruments, and the data were collected from Sep.10 to Sep. 29 with self-administered questionnaires. We analyzed the data using descriptive statistics, Pearson correlation, t-test and ANOVA with SPSS win. Results: 1) The mean score of family life events stress was 25.8, family functioning was 47.2, and social support was 43.4(4 point scale), 2) The rate of correlation between family life events stress and family functioning was (r=-.18), that between family life events stress and social support was (r=-.26), and that between family functioning and social support was (r=0.46). 3) The mean score of family life events stress by general characteristics was significant in age, religion and family type. The mean score of family functioning by general characteristics was significant in education. The mean score of social support by general characteristics was not significant. Conclusion: Considering the results above, we can recognize that there are close relations among family life events stress, family functioning and social support. Although the correlation coefficient is somewhat different, these three variables are very significant for wives.

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Quality of Life and Psychological Well-Being of Breast Cancer Survivors in Jordan

  • Abu-Helalah, Munir;Al-Hanaqta, Motasem;Alshraideh, Hussam;Abdulbaqi, Nada;Hijazeen, Jameel
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.14
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    • pp.5927-5936
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    • 2014
  • Introduction: Breast cancer is the most common cancer among Jordanians. Breast cancer patients suffer from several negative consequences after treatment and these include pain, fatigue, sexual problems, appearance and body image concerns, with psychological dysfunction. This could affect the patient quality of life and psychological well-being. To the best of our knowledge, there is no published quantitative data on the quality of life and psychological well-being of breast cancer patients in Jordan. The objective of this study was to obtain such data and assess predictors with calculated scores. Methods: In this cross-sectional study conducted among breast cancer patients in Jordan diagnosed in 2009 and 2010, assessment was performed using the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ-C30), the Breast Module (QLQ-BR23) and the Hospital Anxiety and Depression Scale (HADS). Clinical, demographic and psychosocial indicators that could predict patient quality of life scores were collected. Results: The number of patients interviewed was 236 (mean age=$50.7{\pm}10.7$ years). The mean Global Health score for the QLQ-C30 was $63.7{\pm}20.2$ SD. Among functional scales, "social functioning" scored the highest ($mean=78.1{\pm}28.6$ SD), whereas "emotional functioning" scored the lowest ($mean=59.0{\pm}SD\;33.5$). For the QLQ-BR23, the worst scores within the functional scales were for "body image" ($mean=52.1{\pm}36.8$ SD) and "future perspective" ($mean=52.9{\pm}38.5$ SD). The worst symptom was "upset by hair loss" ($mean=69.8{\pm}43.0$). The mean HADS scores was $18.{\pm}9.0$ SD. Out of study participants, 53% scored abnormal on the anxiety scale and 45% on the depression scale. Severe depression and severe anxiety were detected among 8% and 14% of study participants, respectively. Statistically significant predictors for individual scores were similar to those reported in published studies, such as the presence of recurrence since baseline, family history of cancer, low educational status, current social problems, extent of the disease, presence of financial difficulties, and employment status. Conclusions and Recommendations: Breast cancer survivors in Jordan have overall good quality of life scores when compared with patients from Western countries. However, their psychological wellbeing is more impaired. There is an urgent need for psychosocial support programs and psychological screening and consultation for breast cancer patients at hospitals of the Ministry of Health in Jordan.

Nonparametric Estimation of Mean Residual Life Function under Random Censorship

  • Park, Byung-Gu;Sohn, Joong-Kweon;Lee, Sang-Bock
    • Journal of the Korean Statistical Society
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    • v.22 no.2
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    • pp.147-157
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    • 1993
  • In the survivla analysis the problem of estimating mean residual life function (MRLF) under random censoring is very important. In this paper we propose and study a nonparametric estimator of MRLF, which is a functional form based on the estimator of the survival function due to Susarla and Van Ryzin (1980). The proposed estimator is shown to be better than some other estimators in terms of mean square errors for the exponential and Weibull cases via Monte Carlo simulation studies.

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