• Title/Summary/Keyword: Testing Validity

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Design of High-Speed LSM Rotary Type Testing Machine in Consideration of Mechanical Strength (기계적 강도를 고려한 초고속 선형동기전동기 회전형 시험기 설계)

  • Seol, Hyun-Soo;Park, Eung-Seok;Lee, Ju;Park, Chan-Bae
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.64 no.5
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    • pp.824-829
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    • 2015
  • The rotary type testing machine undergoes mechanical stress as an external force is applied. In case of the rotary type testing machine, even a tiny flaw results in a fatal demage because the size of the machine is huge. Therefore, when designing the rotary type testing machine, it is necessary to secure a safety factor with the mechanical stress analysis in order to prevent the machine from being destroyed due to scattering or transformation of rotating field. This thesis proposes a LSM rotary type tesitng machine which rotates at the speed of up to 600km/h. And the mechanical stress is considered in order that the safety factor remains above 1.5 at the maximum speed. In addition, because normal force as well as thrust occurs in the machine, the normal force exerted was considered through the strength analysis. Finally, a design plan which enables to weaken the normal force affecting the rotary type testing machine is introduced and its validity is proved by the results of FEM analysis.

Energy Management of a Grid-connected High Power Energy Recovery Battery Testing System

  • Zhang, Ke;Long, Bo;Yoo, Cheol-Jung;Noh, Hye-Min;Chang, Young-Won
    • Journal of Electrical Engineering and Technology
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    • v.11 no.4
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    • pp.839-847
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    • 2016
  • Energy recovery battery testing systems (ERBTS) have been widely used in battery manufactures. All the ERBTS are connected in parallel which forms a special and complicated micro-grid system, which has the shortcomings of low energy recovery efficiency, complex grid-connected control algorithms issues for islanded detection, and complicated power circuit topology issues. To solve those shortcomings, a DC micro-grid system is proposed, the released testing energy has the priority to be reutilized between various testing system within the local grid, Compared to conventional scheme, the proposed system has the merits of a simplified power circuit topology, no needs for synchronous control, and much higher testing efficiency. The testing energy can be cycle-used inside the local micro-grid. The additional energy can be recovered to AC-grid. Numerous experimental comparison results between conventional and proposed scheme are provided to demonstrate the validity and effectiveness of the proposed technique.

On the Test of the reliability and validity of the Disabled's Motivation Scale for Rehabilitation (장애인의 재활동기 측정도구의 신뢰도 및 타당도 검정 연구)

  • Han, Hye-Sook;Lim, Nan-Young
    • The Korean Journal of Rehabilitation Nursing
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    • v.5 no.2
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    • pp.124-133
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    • 2002
  • Purpose: to test of the reliability and validity of the Disabled's Motivation for Rehabilitation Scale, which was developed in 2002. Method: An experimental version of the scale was distributed to a sample of 441 disabled with ages above 18 and below 80 years. The subjects of the test-retest were 60 disabled. Results: revealed a satisfactory level of test-retest and internal consistency. The overall fit of the factor model to the data was good. Correlation among the subscales revealed a simple pattern that, in general, provides support for the self-determination continuum and the construct validity. In testing concurrent, criterion-validity, there was a positive correlation between the motivation scores for rehabilitation and the Health-Related Hardiness scores and a negative correlation between the motivation scores for rehabilitation and the Learned Helplessness scores. Conclusion: The Disabled's Motivation for Rehabilitation Scale revealed a useful instrument with a high degree of reliability and validity. In this sense, this instrument can be effectively utilized in rehabilitative nursing for the disabled.

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Validity and Reliability of the Korean Version of the Ethical Sensitivity Questionnaire for Nursing Students (간호대학생의 한국어판 윤리적 민감성 측정도구 타당도와 신뢰도)

  • Min, Hye Young;Kim, Yoon Jung;Lee, Jung Min
    • Research in Community and Public Health Nursing
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    • v.31 no.4
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    • pp.503-513
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    • 2020
  • Purpose: The purpose of this study was to evaluate the validity and reliability of the Korean version of the Ethical Sensitivity Questionnaire for Nursing Students (KESQ-NS). Methods: The participants were 138 nursing students who have experience in clinical practice. The Korean version of ESQ-NS (KESQ-NS) was examined using content validity, construct validity, criterion-related validity, and testing of internal consistency reliability. Data were collected from November to December of 2019 through an online-survey. Results: The KESQ-NS that was composed of 13 items was divided into three dimensions: Critical understanding of the patient, patient holistic care, patient privacy, and confidentiality. The instrument explained 67.9% of the total variance for ethical sensitivity. Cronbach's α was .88. Conclusion: The KESQ-NS showed good validity and reliability. This instrument can be used to evaluate ethical sensitivity in nursing students in Korea.

Development of the Hospital Nurses' Silence Behavior Scale (병원 간호사의 침묵 행위 측정도구 개발)

  • Chung, Soojin;Hwang, Jee-In
    • Journal of Korean Academy of Nursing
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    • v.54 no.2
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    • pp.279-295
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    • 2024
  • Purpose: This study aimed to develop a scale to measure hospital nurses' silence behavior and examine its validity and reliability. Methods: A total of 52 preliminary items on hospital nurses' silence behavior were selected using a content validity test by seven experts on 53 candidate items derived from a literature review and in-depth interviews with 14 nurses. A total of 405 hospital nurses participated in a psychometric testing. Data analysis comprised item analysis, exploratory and confirmatory factor analyses, and convergent and discriminant validity tests. Pearson's correlation coefficient was used for assessing concurrent validity, and Cronbach's alpha was used for the reliability test. Results: The final scale consisted of nine factors with 31 items, exhibiting acceptable model fit indices, convergent validity, and discriminant validity. The score of the entire scale was positively correlated with the 'Organizational Silence Scale (OSS)-the issues on which nurses remain silent' (r = .60, p < .001) and 'OSS-the reasons why nurses remain silent' (r = .68, p < .001). Cronbach's α of the scale was .92, and α of each subscale ranged from .71 to .90. Conclusion: The Hospital Nurses' Silence Behavior Scale is a useful tool for assessing multifaceted silence behavior among nurses. It can provide basic data for developing better communication strategies among nurses and other hospital staff.

A Questionnaire Design Strategy for Enhancing the Rationality and Testing for the Validity of Choice Experiments Using Example Choice Questions (Choice Experiments의 합리성 제고 및 타당성 검증을 위한 설문지 디자인 연구 - 예제 도입 방안을 중심으로 -)

  • Kim, Yong-Joo
    • Environmental and Resource Economics Review
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    • v.14 no.1
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    • pp.1-24
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    • 2005
  • One of the most important factors that determine the quality of a stated preference study is questionnaire design. This study introduces strategies for enhancing the rationality and testing for the validity of choice experiments(CE) using "example" choice questions that mimic the main choice questions. From the case study of WTP for reduced radon radiation exposures in the home, the study found that screening out irrational responses, 12% of the effective responses, resulted in a meaningful increase in model fit. Meanwhile the study tested for anchoring effects, as a way of confirming the divergent validity of the study, by looking at equality of models estimated for two subsamples. The overall test results were mixed. The pros and cons of the questionnaire design strategy employed are also reported.

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Reliability and Validity of Ultrasound Imaging and sEMG Measurement to External Abdominal Oblique and Lumbar Multifidus Muscles (외복사근과 다열근에 대한 초음파 영상과 표면 근전도 측정방법의 신뢰도와 타당도)

  • Kim, Chang-Yong;Choi, Jong-Duk;Kim, Suhn-Yeop;Oh, Duck-Won;Kim, Jin-Kyung
    • Physical Therapy Korea
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    • v.18 no.1
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    • pp.37-46
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    • 2011
  • The purpose of this study was to investigate intra-rater reliability and determine the validity of electromyography (EMG) measurements to represent muscle activity and ultrasonography (US) to represent muscle thickness during manual muscle testing (MMT) to external abdominal oblique (EO) and lumbar multifidus (MF). Twenty healthy subjects were recruited for this study and asked to perform MMT at differing levels. The subjects' muscle activity using EMG was measured by a ratio to maximum voluntary contraction (MVC) and root mean square (RMS) methods. The subjects' muscle thickness using US was measured by raw muscle thickness and change ratio of thickness to maximum (MVC) or resting condition. In three trials, measurements were performed on each subject by one examiner. The intra-rater reliability of measurements of EMG and US to EO and MF was calculated using intra-class coefficients. The intra-rater reliability of all measurements was excellent (ICC=.75~.98) in EMG and US. The conduct validity was calculated by one-way ANOVA with repeated measurements to compare whether the EMG and US measurements were different between MMT at different levels. There was only a significant difference between all grades at %MVC thickness measurement of US. These results suggest that a %MVC thickness measurement of US was a more sensitive and discriminate in all manual muscle testing grades. This information will be useful for the selection of US measurement and analysis methods in clinics.

Development of Formative Constructs and Measurements for Performance Evaluation of Information Systems (정보시스템 성과평가를 위한 형성적 구성변수(Constructs) 및 측정지표 개발)

  • Kim, Sanghoon;Kim, Changkyu
    • Journal of Information Technology Services
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    • v.11 no.4
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    • pp.135-151
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    • 2012
  • Traditionally in IS studies, the relationship between construct and its measurement items tends to be assumed to be reflective, meaning that the measurements are a reflection of the construct. In reality, however, the nature of the construct can be often formative, which means that its measurement items describe and define the construct rather than vice versa. The purpose of this study was to investigate theoretical and empirically-analysed differences between formative construct and reflective construct through comprehensive interdisciplinary literature review. And then on the basis of these differences, we intended to derive the rule of specifying whether the construct is formative or reflective and propose the methodology of testing the validity(content validity, construct validity, internal consistency and external construct) of formative construct and its measurements, differentiated from that in the case of reflective construct. Also, we suggested the concrete statistical testing methods such as VTT(Vanishing Tetrad Test), MIMIC(Multiple Indicators and Multiple Causes) test and multi-collinearity test. In order to examine the applicability of this methodology to developing the constructs for performance evaluation of IS(Information Systems), we tried to identify its attribute(formative or reflective) and test the validity for the construct arbitrarily chosen among them which had been derived in our previous IS performance evaluation study by using this methodology. The result of the examination was that the methodology proposed in this study was significantly valid and effective in the area of IS performance evaluation.

Elastic modulus in large concrete structures by a sequential hypothesis testing procedure applied to impulse method data

  • Antonaci, Paola;Bocca, Pietro G.;Sellone, Fabrizio
    • Structural Engineering and Mechanics
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    • v.26 no.5
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    • pp.499-516
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    • 2007
  • An experimental method denoted as Impulse Method is proposed as a cost-effective non-destructive technique for the on-site evaluation of concrete elastic modulus in existing structures: on the basis of Hertz's quasi-static theory of elastic impact and with the aid of a simple portable testing equipment, it makes it possible to collect series of local measurements of the elastic modulus in an easy way and in a very short time. A Hypothesis Testing procedure is developed in order to provide a statistical tool for processing the data collected by means of the Impulse Method and assessing the possible occurrence of significant variations in the elastic modulus without exceeding some prescribed error probabilities. It is based on a particular formulation of the renowned sequential probability ratio test and reveals to be optimal with respect to the error probabilities and the required number of observations, thus further improving the time-effectiveness of the Impulse Method. The results of an experimental investigation on different types of plain concrete prove the validity of the Impulse Method in estimating the unknown value of the elastic modulus and attest the effectiveness of the proposed Hypothesis Testing procedure in identifying significant variations in the elastic modulus.

The Validity and Reliability of the Korean Version of Readiness for Practice Survey for Nursing Students (한국어판 간호학생 간호실무준비도 측정도구의 타당도와 신뢰도)

  • Lee, Tae Wha;Ji, Yoonjung;Yoon, Yea Seul
    • Journal of Korean Academy of Nursing
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    • v.52 no.6
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    • pp.564-581
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    • 2022
  • Purpose: This study aimed to evaluate the validity and reliability of the Korean version of the Readiness for Practice Survey (K-RPS). Method: The English Readiness for Practice Survey was translated into Korean using the Translation, Review, Adjudication, Pretesting, and Documentation (TRAPD) method. Secondary data analysis was performed using the dataset from the New Nurse e-Cohort study (Panel 2020) in South Korea. This study used a nationally representative sample of 812 senior nursing students. Exploratory and confirmatory factor analyses were also conducted. Convergent validity within the items and discriminant validity between factors were assessed to evaluate construct validity. Construct validity for hypothesis testing was evaluated using convergent and discriminant validity. Ordinary α was used to assess reliability. Results: The K-RPS comprises 20 items examining four factors: clinical problem solving, learning experience, professional responsibilities, and professional preparation. Although the convergent validity of the items was successfully verified, discriminant validity between the factors was not. The K-RPS construct validity was verified using a bi-factor model (CMIN/DF 2.20, RMSEA .06, TLI .97, CFI .97, and PGFI .59). The K-RPS was significantly correlated with self-esteem (r = .43, p < .001) and anxiety about clinical practicum (r = - .50, p < .001). Internal consistency was reliable based on an ordinary α of .88. Conclusion: The K-RPS is both valid and reliable and can be used as a standardized Korean version of the Readiness for Practice measurement tool.