• 한국자동차공학회논문집
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• 제22권2호
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• pp.100-106
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• 2014

Lower control arm (LCA) is a part of chassis in automotive. Performances of LCA such as stiffness, durability and permanent displacement must be considered in design optimization. However it is hard to consider different performances at once in optimization because these are measured by different commercial tools like Radioss, Abaqus, etc. In this paper, firstly, we construct the integrated design automation system for LCA based on Matlab including Hypermesh, Radioss and Abaqus. Secondly, Akaike information criterion (AIC) is used for assessment of reliability of LCA. It can find the best estimated distribution of performance from limited and discrete stochastic information and then obtains the reliability from the distribution. Finally, we consider tolerances of design variables and variation of elastic modulus and achieve the target reliability by carrying out reliability-based design optimization (RBDO) with the integrated system.

• 대한기계학회논문집A
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• 제38권11호
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• pp.1257-1264
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• 2014

최근 제4세대 원자로의 기기 최적설계를 위해 목표파손확률 기반 설계기법에 대한 연구가 활발히 진행되고 있다. 시스템기반코드(System-Based Code, SBC)가 대표적인 예로 설계 혹은 평가 결과는 부분안전계수(Partial Safety Factor, PSF)의 형태로 도출된다. 따라서 부분안전계수는 가동 기간 중 목표파손확률 기반 설계 및 평가를 위한 핵심 요소 가운데 하나이다. 본 연구에서는 특정 목표파손확률 하에서 원주방향 관통균열이 존재하는 배관의 탄소성 균열개시 조건에 대한 부분안전계수 계산 기법을 정립하고 각 평가 인자가 균열개시에 미치는 중요도를 정량적으로 평가하였다. 균열 배관의 J-적분은 GE/EPRI법과 참조응력법으로 계산하였으며, 부분안전계수는 일차 및 이차신뢰도지수법으로 계산하였다. 또한 재료물성치의 통계적 분포 특성이 미치는 영향도 함께 평가하였다.

• 한국수자원학회논문집
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• 제33권1호
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• pp.15-30
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• 2000

본 연구는 소규모 저수지의 위험도와 초기저수지 수위와의 관계를 설정하기 위하여 신뢰도 분석기법을 적용하였다. 저수지의 안전성을 평가하기 위해서는 변수들의 불확실성을 파악하여야 하며 기능 수행함수를 설정하여야 한다. 저수지의 위험도를 산정하는 절차는 우선 월류에 대한 기능수행함수의 위험도 기준을 설정한 후 변수들의 불확실성을 파악하고 적정한 신뢰도 분석기법에 의하여 위험도를 산정하게 된다. 적용된 신뢰도 분석기법은 MCS(Monte Carly simulation) 법과 MVFOSM (mean value first order second momet) 법이며 이를 이용하여 저수지의 위험도를 산정하였다. 이에 따라 설계 재현기간에 따른 위험도-초기 저수지 수위의 관계를 설정하였으며 이는 저수지의 운용에 유용하게 사용될 것으로 생각된다.

• Asian Pacific Journal of Cancer Prevention
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• 제14권5호
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• pp.2777-2782
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• 2013

The aim of the present study was to assess criterion validity and external reliability of a questionnaire on risk factors for breast cancer. Materials and Methods. Women with breast cancer diagnosis (the cases) (N=40) and matched individuals without cancer (the controls) (N=40) were asked to fill in a questionnaire twice: on a day of admission to hospital (Q1) and on a day before discharge (Q2), with a time interval of 4-6 days. The questionnaire included questions (N=150) on demographic and socioeconomic factors, diseases in the past, family history of cancer, woman's health, smoking, alcohol use, diet, physical activity, and work environment. Criterion validity of the questionnaire Q2 relative to reference questionnaire Q1 was assessed with the Spearman correlation coefficient (SCC); external reliability of the questionnaire was measured in terms of the intraclass correlation coefficient (ICC). Statistical analysis was performed with SPSS 16. Results. The responses to most of the questions on socioeconomic factors, family history on cancer, female health, lifestyle risk factors (smoking, alcohol use, physical activity) correlated substantially in both the cases and the controls with SCC and ICC>0.7 (p<0.01). Statistically non significant relationships defined only between the responses on amount of beer the cases drank at the ages up to 25 years and 26-35 years as well as time of use of estrogen and estrogens-progestin during menopause by the cases. Moderate and substantial SCC and ICC were determined for different food items. Only the response of the cases on veal consumption did not correlate significantly. Conclusions. The questionnaire on breast cancer risk factors is valid and reliable for most of the questions included.

• 여성건강간호학회지
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• 제26권2호
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• pp.141-150
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• 2020

Purpose: High-quality nursing care must be provided for women with infertility, and their nursing needs must be identified. Although scales have been developed to assess infertility-related stress, quality of life, and psychosocial status, there is a lack of scales that assess the nursing needs of women with infertility. The purpose of this study was to develop a needs assessment scale for nursing care in women with infertility and to verify its reliability and validity. Methods: The 250 subjects in this study were women with infertility recruited from four hospitals. The scale was developed following the framework of DeVellis, through a literature review, in-depth interviews, development of preliminary items, verification of content validity, development of secondary items, verification of construct validity, and extraction of the final items. Date were analyzed using item analysis, factor analysis, confirmatory factor analysis, Pearson correlation coefficients, and Cronbach's alpha. Reliability was tested using Cronbach's alpha, and validity was evaluated using item analysis, exploratory factor analysis, and criterion validity. Results: The final version of the nursing needs assessment scale for woman with infertility consisted of 18 items. Four factors (physical and psychological nursing needs, needs for information regarding treatment, needs for infertility-related understanding and concern, and supportive needs) explained 66.0% of the total variance. Cronbach's alpha was .92 for the overall instrument and ranged from .88 to .91 for the subscales. Conclusion: These results suggest that this needs assessment scale for nursing care in women with infertility demonstrated acceptable validity and reliability and contained items suitable for assessing the level of nursing care needed by women with infertility.

• 전기학회논문지
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• 제67권4호
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• pp.505-511
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• 2018

Long term capacity expansion planning has to be carried out to satisfy pre-defined system reliability criterion. For purpose of assessing system reliability, probabilistic simulation technique has been widely adopted. However, the way how to approximate generator outage, especially maintenance outage, in probabilistic simulation scheme can significantly influence on reliability assessment. Therefore, in this paper, 3 different maintenance approximation methods are applied to investigate the quantitative impact of maintenance approximation method on long term capacity expansion planning.

• 한국환경복원기술학회지
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• 제10권5호
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• pp.20-30
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• 2007

Environmental Conservation Value Assessment Map (ECVAM) is the class map to divide the national land into conservation areas and development areas based on legal and ecological assessment criteria. It contributes to enhancements of the efficiency and the scientificity when framing a policy in various fields including the environment. However, it is impossible to understand the multiphase vegetation structure as data on judging the national forest class in ECVAM are restricted to areal information of Ecological Nature Status, Degree of Green Naturality and Forest Map. This point drops the reliability of ECVAM. Therefore we constructed vegetation information using LiDAR (Light Detection And Raging) technology. We generated Biomass Class Maps as final results of this study, to introduce the new forest assessment criterion in ECVAM that alternates or makes up for existing forest assessment criteria. And then, we compared these with Forest Map and Landsat TM NDVI image. As a result, biomass classes are generally higher than stand age classes and DBH classes of Vegetation Map, and lower than NDVI of Landsat TM image because of the difference of time on data construction. However distributions between these classes are mostly similar. Therefore we estimates that it is possible to apply the biomass item to the new forest assessment criterion of ECVAM. The introduction of the biomass in ECVAM makes it useful to detect the vegetation succession, to adjust the class of the changed zone since the production of Vegetation Map and to rectify the class error of Vegetation Map because variations on tree heights, forest area, gaps between trees, vegetation vitality and so on are acquired as interim findings in process of computing biomass.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2004년도 춘계학술대회 논문집
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• pp.502-505
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• 2004

The purpose of this experiment is to modify diagnosis criterion of isothermal relaxation current(IRC) measurement equipment which is using for distribution cable diagnosis. We're using this system for several years in the field instead of DC leakage current measurement and lots of cables were replaced. But we have to investigate on the reliability of this equipment for our cables because we didn't carried out condition assessment of extracted cables after field diagnosis by this equipment. It is important thing for cable maintenance. If the replacement criterion is improper we can not prevent failures or will waste budget on account of replacement of the sound cables. In this papar we selected field installed cables and injected silicone fluid to the cables for insulation rehabilitation. In order to prove reliability of the diagnosis equipment we compared diagnosis results and AC breakdown strength according to operating time after silicone treatment. This is the results of the field test for 1 year.

• 한국전문물리치료학회지
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• 제27권2호
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• pp.111-117
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• 2020

Background: The Functional Assessment of Chronic Illness Therapy (FACIT) for Dyspnea was developed to assess multidimensional dyspnea using two subscales (experience of dyspnea and functional limitation) and a total score. Objects: This study aimed to assess the reliability and validity of the Korean version of the FACIT-dyspnea 10-item short form questionnaire (FACIT-dyspnea-K). Methods: Subjects were 163 patients with cancer. Dyspnea-related scales (modified Medical Research Council scale [mMRC], European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30 [EORTC QLQ-C30], Hospital Anxiety and Depression [HAD], and WHO Performance Scale) were used to validate the FACIT-dyspnea-K. Results: Internal consistency was confirmed by Cronbach's alpha values of 0.90 and 0.95 in factors 1 and 2, respectively. Convergence validity was determined by comparing the two factors and total score of the FACIT-dyspnea-K with conceptually related assessment tools measuring the physical and emotional effects of dyspnea, with which correlations ranged from 0.364 to 0.567. Criterion validity was established by significant differences in the FACIT-dyspnea-K score between groups when the patients were classified by performance status as assessed by the WHO performance scale. Furthermore, the FACIT-dyspnea-K showed notable correlations with other dyspnea scales (mMRC, EORTC QLQ-C30, and HAD) for cancer patients (r = 0.28 to 0.54). The test-retest reliability of the two factors and total score of the FACIT-dyspnea-K appeared to be excellent (Cronbach's alpha = 0.96 to 0.97). Conclusion: This study supports FACIT-dyspnea-K as a valid and reliable instrument to assess the dyspnea experience of cancer patients in clinical settings.

• 보건의료산업학회지
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• 제9권2호
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• pp.89-102
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• 2015

Patients unable to speak are at higher risk for untreated pain. Use of valid behavioral and physiologic measures for pain is highly recommended for uncommunicative patients. This study was performed to compare the reliability and validity of NVPS-K and CPOT-K for pain assessment of nonverbal patients. This study was conducted from July to November 2011. A total of 29 nonverbal adult patients admitted to a university hospital intensive care unit participated in this study. Interrater reliability of the NVPS-K and CPOT-K had intermediate to high intraclass correlation coefficients (NVPS-K 0.680 ~ 0.921, CPOT-K 0.710 ~ 0.896). Discriminant validity was supported with higher instrument scores during turning and endotracheal suctioning than that of NIBP. For criterion validity, the NVPS-K scores were correlated to the self-reported pain of the patients but not the CPOT-K scores. The areas under the ROC curve for the NVPS-K and CPOT-K were 0.748 and 0.696 with cutoff points of 1 and 2, respectively. Thus, the NVPS-K and CPOT-K had a sensitivity and specificity of 94.7% and 45.0%, and 60.5% and 75.0%, respectively. The NVPS-K and CPOT-K are reliable and valid tools to assess pain in nonverbal patient and thus, are recommended for the assessment of the pain in nonverbal patients.