• Title/Summary/Keyword: Reliability Measures

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Reliability analysis of circular tunnel with consideration of the strength limit state

  • Ghasemi, Seyed Hooman;Nowak, Andrzej S.
    • Geomechanics and Engineering
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    • v.15 no.3
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    • pp.879-888
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    • 2018
  • Probability-based design codes have been developed to sufficiently confirm the safety level of structures. One of the most acceptable probability-based approaches is Load Resistance Factor Design (LRFD), which measures the safety level of the structures in terms of the reliability index. The main contribution of this paper is to calibrate the load and resistance factors of the design code for tunnels. The load and resistance factors are calculated using the available statistical models and probability-based procedures. The major steps include selection of representative structures, consideration of the limit state functions, calculation of reliability for the selected structures, selection of the target reliability index and calculation of load factors and resistance factors. The load and resistance models are reviewed. Statistical models of resistance (load carrying capacity) are summarized for strength limit state in bending, shear and compression. The reliability indices are calculated for several segments of a selected circular tunnel designed according to the tunnel manual report (Tunnel Manual). The novelty of this paper is the selection of the target reliability. In doing so, the uniform spectrum of reliability indices is proposed based on the probability paper. The final recommendation is proposed based on the closeness to the target reliability index.

A Study of MOE Establishment for Improving the Credibility of UGV Effectiveness Analysis (무인지상로봇 효과분석의 신뢰성 향상을 위한 효과척도 설정방안 연구)

  • Lee, Jaeyeong;Pyun, Jaijeong;Kim, Chongman
    • Journal of Applied Reliability
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    • v.14 no.3
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    • pp.197-202
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    • 2014
  • In the 21st century, the roles of UGV in the ground battle draw its attention and many research about how to use it is going on globally, but not many study is doing about how to measure its combat effectiveness in the battle. Basically, the effectiveness of UGV is different from its mission profile. Hence, we proposed Measures Of Effectiveness which can measure the UGV effectiveness based on five different missions such as mine detection, nbc detection, reconnaissance, rescue, and fire mission. We expect that these Measures Of Effectiveness proposed are able to contribute to increase the credibility of the study results for UGV effectiveness. We also hope that this paper can stimulate to expand the research scope and related field about UGV effectiveness in the future.

Validating MEDIQUAL Constructs: Reliability, Empathy, Assurance, Tangibles, and Responsiveness

  • Lee, Sang-Gun;Sangjin Yoo;Lee, Hu-Hyuk
    • Journal of Korea Society of Industrial Information Systems
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    • v.8 no.1
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    • pp.121-130
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    • 2003
  • In this paper, we validate MEDIQUAL constructs through different media users in help desk. In a previous paper only two end-users' constructs were used: assurance and responsiveness. In this paper we extended MEDIQUAL constructs to include reliability, empathy, assurance, tangibles, and responsiveness, which are based on the SERVQUAL theory. The results suggested that: 1) five MEDIQUAL constructs were validated through the factor analysis. That is, importance of the constructs have relatively high correlations between measures of the same construct using different methods and low correlations between measures of construct that are expected to differ (Cronbach, 1971; Campbell and Fiske, 1959) 2) five MEDIQUAL constructs are statistically significant on media users' satisfaction in help desk service by regression analysis.

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Development of Integrated Model for Accelerated Life Test Using Linkage Parameter (연계모수를 이용한 가속수명시험 통합모형의 개발)

  • Choi, Sung-Woon
    • Journal of the Korea Safety Management & Science
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    • v.9 no.5
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    • pp.43-48
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    • 2007
  • This paper is to present linkage parameter to integrate statistical models and physical models for accelerated life test. Statistical models represent the relationship of probability distribution and life. Physical models show the relationship of life and stress. Moreover, this study proposes the four steps for construction of integrated models for accelerated life test using linkage parameter. Finally, this paper develops new integrated models such as extreme value distribution-general Eyring, linearly increasing failure rate function-general Eyring, etc., and estimates various reliability measures.

Interrater and Intrarater Reliability for Three Clinical Measures of Balance and Gait in Individuals With Hemiparetic Stroke (뇌졸중 환자률 대상으로 한 균형 및 보행에 관한 3가지 임상평가도구의 측정자간 및 측정자내 신뢰도)

  • Woo, Young-Keun;Park, So-Yeon;Hwang, Su-Jin;Kim, Hyouk-Il;Yoo, Kyoung-Hoon
    • PNF and Movement
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    • v.9 no.2
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    • pp.45-53
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    • 2011
  • Purpose : Many researchers have attempted to identity the reliability used in clinical examination of balance and gait performance for individuals of hemiparetic stroke. The study aims to evaluate whether the reliabilities of three popular clinical measures of balance and gait performance was consistency regardless of applicate experience of those clinical measures compared with previous studies for persons with hemiparetic stroke. Methods : A total of three hemiparetic stroke populations and twenty-six physical therapists were recruited from Glory hospital, Inchen, Korea in this study. The three clinical measures, involving Berg balance test (BBT), dynamic gait index (DGI), and Tinetti performance-oriented mobility assessment (POMA), were assessed in two sessions that were seven days apart. Results : The POMA was showed a good intrarater and interrater reliabilities in people with hemiparetic stroke regardless of measure's experience in clinical field. However BBT and DGI were showed below moderate intrarater and interrater reliabilities. Conclusion : The POMA could be a reliable measure to evaluate functional postural stability and gait performance in hemiparetic stroke patients compared with other two clinical measures regardless of measure's experience of physical therapists.

The Development of a Client Health Status Outcome Evaluation Instrument in Home Care (가정간호대상자의 건강상태 결과 평가도구 개발)

  • 박현태
    • Journal of Korean Academy of Nursing
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    • v.34 no.3
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    • pp.552-564
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    • 2004
  • Purpose: This study was to develop a client health status outcome evaluation instrument, and examine content validity, reliability, construct validity, and the acceptability of this instrument. Method: A preliminary list was made of such key information as standards, criteria, indicators and measures, by means of a broad review of literature within the field. After determining the preliminary instruments, the study sought to obtain examination, consensus, and modification of two groups of experts in the home-care field. Finally, the instrument examined content validity, reliability, construct validity, and the acceptability of this instrument. Result: The tool was considered of 13 criteria, 48 indicators, and 167 detail measures. The content validity index of the tool was above 0.8 according to the expert group. Regarding the reliability of the evaluators of standards 1 and 2, the degree of agreement between evaluators was high(96.4% through 98.2%). Construct validity in this study, the difference in the mean score between the baseline point and the follow up point of each of standards 1 and 2 was significant, and the mean score of the follow up point was more than that of the baseline point. After examining the acceptability of this instrument with practice managers and home care nurses in home care institutions, a positive opinion was given of this instrument, and it was indicated that to be useful and applicable in home care practice. Conclusion: The results of evaluating client outcome will contribute to overall outcome-based quality improvement and service marketing in home care by providing a constant gauge of home care effectiveness.

Availability of the Pendulum Test Using NK Table for Spasticity Measurement of Low Extremity (하지 강직 평가에 있어 NK테이블을 이용한 진자검사의 유용성)

  • Kim, Yong-Wook;Weon, Jong-Hyuck;Kim, Tae-Ho
    • Journal of the Korean Society of Physical Medicine
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    • v.8 no.2
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    • pp.209-217
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    • 2013
  • PURPOSE: The purpose of this study was to investigate the clinical availability of the pendulum test (through reliability and validity) using a NK table attached electrogoniometer for spasticity measurement in patients with brain lesions. METHODS: Thirty-one stroke and traumatic brain injury subjects participated in the study. Intraclass correlation coefficient (ICC) was used to verify the test-retest reliability of spasticity measures of the pendulum test. Pearson's product correlation coefficient was used to examine the validity of the pendulum test through the amplitude of the deep tendon reflex (DTR) test known for objective and quantitative measure of spasticity. RESULTS: In these results, the test-retest reliability was showed significantly high correlation between pendulum tests (ICCs=.95~.97, p<.01). There were significant negative correlations between the amplitude of the DTR test and all measures of spasticity of the pendulum test(r=-.77~-.85, p<.01). CONCLUSION: Thus, it is possible to use the pendulum test using a NK table as an objective measure of spasticity, rather than other expensive equipment, which is more complicated to use. Further studies are needed to explore the therapeutic effects of spasticity using a newly designed pendulum test equipment in this study.

Evaluation of Survey Data Quality Based on Interviewers' Assessments: An Example from Taiwan's Election and Democratization Study

  • Tsai, Chi-lin;Liu, Tsung-Wei;Chen, Yi-ju
    • Asian Journal for Public Opinion Research
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    • v.7 no.1
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    • pp.57-74
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    • 2019
  • Researchers usually examine the quality of survey data by several conventional measures of reliability and validity. However, those measures are mainly designed to examine the quality of an individual measurement, rather than the quality of a data set as a whole. There is a relative lack of methods for evaluation of the overall data quality. This paper attempts to fill this gap. We propose using interviewers' assessments as one of criteria for evaluating the overall data quality. Interviewers are the ones who literally conduct and thus directly observe interviews. Taiwan's Election and Democratization Studies (TEDS) have required interviewers to assess how trustworthy the responses of each of their interviewees are, and to provide several descriptions about the process and environment of the interviews. We use this information to evaluate the data quality of TEDS surveys and compare it with the results from the conventional test-retest method. The findings are that the interviewer assessment is a fair indicator of the overall reliability of attitudinal questions but not a good indicator when factual questions are examined. Regarding the evaluation of data validity, more data is required to see whether or not interviewers' assessment is informative in terms of data quality.

A Study on Countermeasures Against Cyber Infringement Considering CPTED

  • Lim, Heon-Wook
    • International Journal of Advanced Culture Technology
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    • v.9 no.2
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    • pp.106-117
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    • 2021
  • The aim is to find cyber measures in consideration of physical CPTED in order to prepare countermeasures for cybercrime prevention. For this, the six applied principles of CPTED were used as the standard. A new control item was created in connection with the control items of ISO27001. A survey was conducted on former and current investigators and security experts. As a result of the reliability analysis, the Kronbar alpha coefficient value was 0.947, indicating the reliability of the statistical value. As a result of factor analysis, it was reduced to six factors. The following are six factors and countermeasures. Nature monitoring blocks opportunities and strengthens business continuity. Access control is based on management system compliance, personnel security. Reinforcement of territoriality is reinforcement of each wife and ethics. Establishment of security policy to enhance readability, security system maintenance. Increasing usability is seeking ways to utilize, periodic incentives. For maintenance, security education is strength and security-related collective cooperation is conducted. The differentiation of this study was to find countermeasures against cybercrime in the psychological part of the past. However, they approached to find in cyber measures. The limitation of the study is to bring the concept of physical CPTED to the cyber concept.

A Study on the Burn-in Optimization of Computer Monitor (Computer용 Monitor 완제품의 Burn-in 최적화에 관한 연구)

  • Park, Jong-Man
    • Journal of Korean Society for Quality Management
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    • v.23 no.4
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    • pp.148-156
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    • 1995
  • The past approach to burn-in optimization have been focused mainly in cost minimization problem during entire product life cycle. But in the case of practical application, burn-in optimization under reliability restriction might be preferred to burn-in optimization by cost minimization. Accordingly this paper shows real examples which estimate the practical burn-in period through application of heuristic method and select the best reliability model through comparison of reliability performance measures.

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