• Title/Summary/Keyword: Reliability tools

Search Result 706, Processing Time 0.024 seconds

Comparison of the Reliability and Validity of Fall Risk Assessment Tools in Patients with Acute Neurological Disorders (급성기 신경계 환자에서 낙상 위험 사정 도구의 신뢰도 및 타당도 비교)

  • Kim, Sung Reul;Yoo, Sung-Hee;Shin, Young Sun;Jeon, Ji Yoon;Kim, Jun Yoo;Kang, Su Jung;Choi, Hea Sook;Lee, Hea Lim;An, Young Hee
    • Korean Journal of Adult Nursing
    • /
    • v.25 no.1
    • /
    • pp.24-32
    • /
    • 2013
  • Purpose: The aim of the study was to identify the most appropriate fall-risk assessment tool for neurological patients in an acute care setting. Methods: This descriptive study compared the reliability and validity of three fall-risk assessment tools (Morse Fall Scale, MFS; St Thomas's Risk Assessment Tool in Falling Elderly Inpatients, STRATIFY; Hendrich II Fall Risk Model, HFRM II). We assessed patients who were admitted to the Department of Neurology, Neurosurgery, and Rehabilitation at Asan Medical Center between July 1 and October 31, 2011, using a constructive questionnaire including general and clinical characteristics, and each item from the three tools. We analyzed inter-rater reliability with the kappa value, and the sensitivity, specificity, predictive value, and the area under the curve (AUC) of the three tools. Results: The analysis included 1,026 patients, and 32 falls occurred during this study. Inter-rater reliability was above 80% in all three tools. and the sensitivity was 50.0% (MFS), 84.4%(STRATIFY), and 59.4%(HFRM II). The AUC of the STRATIFY was 82.8. However, when the cutoff point was regulated as not 50 but 40 points, the AUC of the MFS was higher at 83.7. Conclusion: These results suggest that the STRATIFY may be the best tool for predicting falls for acute neurological patients.

Reliability Improvement Using Experimental Design

  • 조진남;백재욱
    • Proceedings of the Korean Reliability Society Conference
    • /
    • 2001.06a
    • /
    • pp.289-289
    • /
    • 2001
  • Experimental design has become one of the primary tools for achieving quality of manufactured products. Because of a devision in the diciplines of quality and reliability, this important tool has not been used to extensively to achieve reliability. In this talk, we describe how experimental design can be used to achieve reliability.

  • PDF

The Reliability of Balance, Gait, and Muscle Strength Test for the Elderly with Dementia: A Systematic Review

  • Lee, Han-Suk;Park, Sun-Wook
    • Journal of the Korean Society of Physical Medicine
    • /
    • v.12 no.3
    • /
    • pp.49-58
    • /
    • 2017
  • PURPOSE: To summarize the evaluation tools of balance [Berg Balance Scale (BBS), timed up and Go (TUG), forward reaching test (FRT)], gait [6 m walking Test (6MWT)], and strength [Chair Stand Test (CST)] for patients with dementia. METHODS: The following databases were searched: Pub MED, Cochrane, Sciences Direct, and Web of Sciences. The inclusion criteria were as follows: 1) repeated measurement design, 2) subjects with dementia, 3) use of testing tools such as the BBS, TUG, FRT, 6MWT, and CST, 4) report the reliability. One reviewer performed the quality assessment of diagnostic accuracy study and two evaluators performed data extraction independently. RESULTS: Six articles and one letter were included. The interrater reliability of 6MWT, TUG, and CST, were acceptable (ICC>.90). However, FRT had unacceptable reliability. In test-retest reliability, only BBS has acceptable reliability (ICC>.90). Others had various reliabilities. The risk of interrater reliability bias was low in all studies. However, the risk of bias of intrarater reliability was low in five studies and moderate in two studies. CONCLUSION: The interrater reliability of the 6MWT, TUG, and CST were acceptable. However, in test-retest reliability, only BBS has acceptable reliability. Therefore, we suggest the use of BBS to test the balance of dementia patients. In addition, the study of tool reliability according to the subtype of dementia is needed in the future.

A Bayesian network based framework to evaluate reliability in wind turbines

  • Ashrafi, Maryam;Davoudpour, Hamid;Khodakarami, Vahid
    • Wind and Structures
    • /
    • v.22 no.5
    • /
    • pp.543-553
    • /
    • 2016
  • The growing complexity of modern technological systems requires more flexible and powerful reliability analysis tools. Existing tools encounter a number of limitations including lack of modeling power to address components interactions for complex systems and lack of flexibility in handling component failure distribution. We propose a reliability modeling framework based on the Bayesian network (BN). It can combine historical data with expert judgment to treat data scarcity. The proposed methodology is applied to wind turbines reliability analysis. The observed result shows that a BN based reliability modeling is a powerful potential solution to modeling and analyzing various kinds of system components behaviors and interactions. Moreover, BN provides performing several inference approaches such as smoothing, filtering, what-if analysis, and sensitivity analysis for considering system.

Review of Spiritual Distress Assessment Tools: A Literature Review (영적 고뇌 측정도구에 대한 고찰)

  • Kim, Jin-Sook
    • Journal of the Korea Convergence Society
    • /
    • v.10 no.7
    • /
    • pp.383-390
    • /
    • 2019
  • This study was done to evaluate current spiritual distress assessment tools and to assess nursing research adapted this spiritual distress assessment tools. Spiritual distress assessment tools were identified through systematic review. Ten studies about spiritual distress assessment tools were identified. In these studies, three international and one domestic standardized assessment tools were found. The purpose of developing these tools was to provide spiritual care through assessing spiritual distress. Domestic assessment tool had low reliability, was not proved by constructive validity, and did not include multidimensional spiritual concepts. International assessment tools may take into account cultural and religious backgrounds in the context for cultural adaptation of instruments. Based on these results, the development of Korean version of spiritual distress assessment tool is recommended.

Screening and Assessment Tools for Measuring Delirium in Patients with Cancer in Hospice and Palliative Care: A Systematic Review

  • Yang, Eun Jung;Hahm, Bong-Jin;Shim, Eun-Jung
    • Journal of Hospice and Palliative Care
    • /
    • v.24 no.4
    • /
    • pp.214-225
    • /
    • 2021
  • Purpose: This study reviewed screening and assessment tools that are used to measure delirium in patients with cancer in hospice and palliative care settings and examined their psychometric properties. Methods: Four databases were searched for studies using related search terms (delirium, tools, palliative care, cancer, and others). The inclusion criteria were a) studies that included screening/assessment tools for measuring delirium in cancer patients receiving hospice/palliative care, and b) studies published in English or Korean. The exclusion criteria were a) studies that were conducted in an intensive care setting, and b) case studies, qualitative studies, systematic reviews, or meta-analyses. Results: Out of the 81 studies identified, only 10 examined the psychometric properties of tools for measuring delirium, and 8 tools were ultimately identified. The psychometric properties of the Memorial Delirium Assessment Scale (MDAS) were the most frequently examined (n=5), and the MDAS showed good reliability, concurrent validity, and diagnostic accuracy. The Delirium Rating Scale had good reliability and diagnostic accuracy. The Delirium Rating Scale-Revised 98 also showed good reliability and structural validity, but its diagnostic performance was not examined in hospice/palliative care settings. The Nursing Delirium Screening Scale showed relatively low diagnostic accuracy. Conclusion: The MDAS showed evidence of being a valid assessment tool for assessing delirium in patients with cancer in palliative care. Few studies examined the diagnostic performance of delirium tools. Therefore, further studies are needed to examine the diagnostic performance of screening/assessment tools for the optimal detection of delirium in patients with cancer in hospice/palliative care.

Evaluation and Design Tools for the Reliability of Wind Power Converter System

  • Ma, Ke;Zhou, Dao;Blaabjerg, Frede
    • Journal of Power Electronics
    • /
    • v.15 no.5
    • /
    • pp.1149-1157
    • /
    • 2015
  • As a key part in the wind turbine system, the power electronic converter is proven to have high failure rates. At the same time, the failure of the wind power converter is becoming more unacceptable because of the quick growth in capacity, remote locations to reach, and strong impact to the power grid. As a result, the correct assessment of reliable performance for power electronics is a crucial and emerging need; the assessment is essential for design improvement, as well as for the extension of converter lifetime and reduction of energy cost. Unfortunately, there still exists a lack of suitable physic-of-failure based evaluation tools for a reliability assessment in power electronics. In this paper, an advanced tool structure which can acquire various reliability metrics of wind power converter is proposed. The tool is based on failure mechanisms in critical components of the system and mission profiles in wind turbines. Potential methodologies, challenges, and technology trends involved in this tool structure are also discussed. Finally, a simplified version of the tool is demonstrated on a wind power converter based on Double Fed Induction Generator system. With the proposed tool structure, more detailed information of reliability performances in a wind power converter can be obtained before the converter can actually fail in the field and many potential research topics can also be initiated.

A study on the Reliability Experiment and the Structural Improvement of Sliding Cover (슬라이딩 커버의 신뢰성 시험 및 구조개선 연구)

  • Song Jun Yeob;Kang Jae Hun;Kim Tae Hyung;Kim Ok Koo
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.22 no.7 s.172
    • /
    • pp.146-154
    • /
    • 2005
  • Recently, the high-speed and intelligence technology of machine tools are developed for the high efficiency of productivity Under the operating condition from the high-speed of machine tools, the various failure modes can occur in core units of manufacturing system. Therefore it is for the reliability concept of machine tool to be required in a design level. And the above-stated technology must be accommodated in the feeding and spindle subsystem, etc those are the core units of machine tools. In this study, we are developed the test-bed of sliding cover (C-plate) in order to evaluating reliability and estimating failure modes of feeding subsystem under operating conditions. The reliability experiment using the developed test-bed and the additional structural analysis executed on single and double structure. We found out the weak parts of sliding cover and were able to predict a life cycle from the experiment results. In this study, we propose the new C-plate model with double link structure to apply the high-speed machine tool in the fundamental guideline.

High Reliability Design for New Concept Machining Center (신개념 머시닝센터의 신뢰성 향상 설계기술)

  • Lee, Chan-Hong;Kim, Yang-Jin
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.28 no.8
    • /
    • pp.894-903
    • /
    • 2011
  • In this paper, the capability index is introduced in order to improve the reliability of new concept machine tools and the method to improve the machine accuracy from the analysis of cutting process, statistical methodology and influence factors are proposed. In addition, the rib structure of bed and column in machine tools is analyzed by using the thermal impact method in order to analogize the rib pattern which has the small thermal deformation under thermal boundary condition. In the analysis of column rib structure, thermal boundary condition is separated to heat conduction and heat transfer to appropriate real boundary condition. Finally, performance chart of bed and column rib structure is provided for designer to estimate each rib pattern and select rib structure appropriating to thermal condition.