• 제목/요약/키워드: Variance Criterion

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미만성 갑상샘 질환에서 GLCM을 이용한 초음파 영상 분석 (Ultrasonic Image Analysis Using GLCM in Diffuse Thyroid Disease)

  • 예수영
    • 한국방사선학회논문지
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    • 제15권4호
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    • pp.473-479
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    • 2021
  • 미만성 갑상샘질환은 그 진단 기준이 모호하고 숙련자의 주관적인 진단에 따라 오류가 많이 발생한다. 또한 갑상샘 결절의 초음파 영상에 관한 연구는 활발히 이루어졌지만 미만성 갑상샘질환에 관한 연구 사례는 미흡한 실정이다. 본 연구에서는 정상과 미만성 갑상샘질환의 영상에 GLCM 알고리즘을 적용하여 영상의 특징을 추출하고 추출된 특징값을 파라미터를 이용하여 정량적인 분석을 하였다. W 병원에서 진단한 환자의 갑상샘 초음파 영상을 대상으로 GLCM 알고리즘을 이용하여 정상 199증례, 경도 132증례, 중등도 99증례 총 영상 430증례에 관심영역(50×50 pixel)을 설정하고, 각 영상에서 Autocorrelation, Sum of squares, Sum average, Sum variance, Cluster prominence, Energy 6가지 파라미터를 이용하여 분석하였다. Autocorrelation, Sum of squares, Sum average, Sum variance 4가지 파라미터에서 Normal, Mild, Moderate를 구분하는데 90%이상의 높은 인식률을 보였다. 미만성 갑상샙질환의 초음파영상에서 GLCM 알고리즘을 이용하여 미만성 갑상샘질환의 심각도 정도를 분류하는 기준으로서 가치가 있다. 이러한 파라미터를 적용하여 갑상샘질환의 진단에 있어 육안 판독에 따른 오류를 감소시키고 미만성 갑상샘질환 진단의 2차적인 수단으로 활용 가능할 것으로 기대된다.

복합실험기준의 설정: 모형과 분산구조 (Composite Design Criteria : Model and Variance)

  • 김영일
    • 응용통계연구
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    • 제13권2호
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    • pp.393-405
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    • 2000
  • 원래 최적실험의 이론은 주어진 모형과 그에 따른 가정에 기초하여 발달되었기 때문에 하나의 최적실험기준이 실험이 가족 있는 여러 목적을 모두 반영하는 것이 무리이다. 따라서 실험자가 다목적 실험기준의 필요성을 느끼는 경우에는 종종 여러 최적실험 기준들의 균형을 이루는 방법을 통해 이러한 문제가 다루어진다. 본 연구에서는 이 분산 구조를 가지고 있는 모형을 예를 들어 복합적인 실험기준들을 알아본다. 왜냐하면 이분산인 경우 D-최적과 G-최적실험간의 동격이론은 더 이상 성립되지 않음에 따라 두 실험기준의 특징은 현격하게 구분되어지기 때문이다. 제약조건최적실험, 결합최적실험, 그리고 minimax 설험방법을 통한 실험기준들간의 균형을 꾀하여 보았다. 처음 두 방법은 실험자의 주관이 반영되어 실제적으로 매우 세심한 주의가 필요한 반면, minimax는 그러한 점을 해소하였다고 본다. 또한 이를 확장하여 오차의 이분산 구조에 대한 불확실성이 존재할 때 적용될수 있는 두 가지 실험기준도 마련하여 보았다. 간단한 알고리즘과 결어를 첨부하였다.

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간호사의 범문화효능감 측정도구 개발 및 타당화 (Development and Psychometric Evaluation of the Transcultural Self-efficacy Scale for Nurses)

  • 오원옥;박은숙;석민현;임여진
    • 대한간호학회지
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    • 제46권2호
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    • pp.293-304
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    • 2016
  • Purpose: This methodological study was conducted to develop and psychometrically test the Transcultural Self-efficacy scale (TCSE-scale) for nurses. Methods: Initial 41 items for the TCSE-scale were generated based on extensive literature reviews and in-depth interviews with 18 nurses who had experience in caring for foreign patients. Cultural Competence and Confidence model was used as a conceptual framework. Content validity was evaluated by an expert panel. Psychometric testing was performed with a convenience sample of 242 nurses recruited from four general hospitals in the Seoul metropolitan area and Gyeonggi-do province of South Korea. To evaluate the reliability of TCSE-scale, a test-retest reliability and an internal consistency reliability were analyzed. Construct validity, concurrent validity, criterion validity, convergent validity and discriminative validity were used to evaluate the validity. Results: The 25-item TCSE-scale was found to have three subscales-Cognitive, Practical, and Affective domain-explaining 91.5% of the total variance. TCSE-scale also demonstrated a concurrent validity with the Cultural Competence Scale. Criterion-related validity was supported by known-group comparison. Reliability analysis showed an acceptable-to-high Cronbach's alpha-.88 in total, and subscales ranged from .76 to .87. The ICC was .90, indicating that the TCSE-scale has internal consistency and stability of reliability. Conclusion: This preliminary evaluation of the psychometric scale properties demonstrated an acceptable validity and reliability. The TCSE-scale is able to contribute to building up empirical and evidence based on data collection regarding the transcultural self-efficacy of clinical nurses. We suggest further testing of the applicability of TCSE-scale in different settings and community contexts.

HF-Radar 관측자료의 단주기 변동성 분석 및 정확도 분류 (Short-Term Variability Analysis of the Hf-Radar Data and Its Classification Scheme)

  • 최영진;김호균;이동환;송규민;김대현
    • 한국해안·해양공학회논문집
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    • 제28권6호
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    • pp.319-331
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    • 2016
  • HF-Radar관측자료의 시간평균 간격에 따른 신호특성을 살펴보고, 국립해양조사원에서 운영하고 있는 HF-Radar관측소별로 수집률과 공분산을 분석하여 자료질이 높은 대표정점을 선점(選點)하였다. HF-Radar관측의 시간평균 간격이 짧아질수록, 취득률은 낮아지나 고주파 신호특성을 관측할 수 있었다. 그러나 조류예측에서는 현행 60분 간격의 평균자료와 20분 간격의 자료에서 취득되는 조류의 차이는 거의 없었다. 수집률 기준을 높이고 공분산을 고려한 자료는 기존에 수집률 50%만을 기준으로 한 정점에 비해 관측품질이 높아졌다.

터보 TCM 디코더의 복호 지연을 감소시키기 위한 효율적인 반복복호 제어기법 (Effective Iterative Control Method to Reduce the Decoding Delay for Turbo TCM Decoder)

  • 김순영;김정수;장진수;이문호
    • 한국전자파학회논문지
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    • 제14권8호
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    • pp.816-822
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    • 2003
  • 본 논문에서는 전력이 제한된 환경에서 사용이 고려되고 있는 터보 TCM(Turbo Trellis Coded Modulation)에 대하여 낮은 복잡도를 갖는 효율적인 반복복호 제어기법을 제안한다. 터보 부호의 복호 과정에서 반복 복호수를 증가하면 성능이 향상되지만 어느 정도의 반복 복호수 이상에서는 성능 향상이 거의 나타나지 않는다. 따라서 복호 계산량과 복호지연을 감소시킬 수 있도록 반복 복호과정을 효율적으로 정지시킬 수 있는 반복복호 제어가 필요하다. 본 논문은 복호지연 및 반복복호 첫수를 줄일 수 있는 효율적인 알고리즘을 제시한다. 제안 기법은 터보 TCM 복호화 과정에서 궤환되는 외부부가정보의 특성에 따른 임계치를 이용하여 반복 복호수를 가변적으로 제어하는 기법이다. 성능 분석 결과 제안구조는 복호과정의 계산량과 지연을 성능 저하 없이 효율적으로 감소시킬 수 있음을 보여준다.

한국어판 간호대학생의 동료돌봄행위척도(Peer Group Caring Interaction Scale)의 타당도 및 신뢰도 분석 (Validity and Reliability of the Peer Group Caring Interaction Scale-Korean Version)

  • 김정희;공문연;오윤희
    • 대한간호학회지
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    • 제46권3호
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    • pp.431-442
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    • 2016
  • Purpose: This paper was conducted to validate the Korean version of the Peer Group Caring Interaction Scale (PGCIS-K) that measures caring behaviors as experienced by nursing students. Methods: Translation of the PGCIS-K was validated through forward-backward translation methods. Survey data were collected from 218 nursing students in a nursing school. Construct validity and criterion-related validity were evaluated. Internal consistency and the Guttman split-half coefficient were calculated to assess reliability. Results: The PGIS-K showed reliability except for 4 items (Cronbach's ${\alpha}=.91$, Guttman split-half coefficient=.85), which were low (<.30) or negatively correlated with the total scale. A 12-item reduced form of the PGCIS-K was developed by item-analysis and construct validity evidence. Factor loading for the 12 items on 2 factors ranged from .47~.82, which explained 58.4% of the total variance. Two factors were named 'modeling and assistance (Cronbach's ${\alpha}=.87$)' and 'communication and sharing (Cronbach's ${\alpha}=.82$)'. Convergent validity, discriminant validity, and criterion validity were supported according to the correlation coefficients of the 2 factors with other measure. Conclusion: The findings suggest preliminary evidence that the 12-item PGCIS-K can be used to measure nursing students' peer group caring interactions in Korea. Additional studies are recommended to continue the psychometric evaluation of this scale. Also, it can be extended to measure graduate nursing students or staff nurses' peer group caring interaction.

한국 사회적지지 측정도구 개발 (Psychometric Evaluation of the Korean Social Support Questionnaire)

  • 오가실;오경옥;이숙자;김정아;정추자;김혜령;전화연;강정희
    • 대한간호학회지
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    • 제38권6호
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    • pp.881-890
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    • 2008
  • Purpose: Research related to social support in Korea has been hampered by paucity of measurement tools reflecting Korean culture. The aim of the study was to develop Korean social support questionnaire (KSSQ) based on the Korean social support pyramid and to test psychometric properties of the KSSQ. Methods: The questionnaire was administered to 701 subjects and 658 college students. Psychometric analyses included factor analyses, expert validity, criterion-related validity, internal consistency, and test-retest reliability. Results: A principal components analysis support for construct validity, eliciting a three factor solution accounting for 65.46% of variance in scores. Concurrent and discriminant validity supported criterion-related validity. Internal consistency of reliability was support with Cronbach's alpha of .97-.98 for the entire scale. Test-retest reliability was .76. Conclusion: This initial testing of KSSQ to measure Korean social support demonstrates evidence of reliability and validity. Assessment of known-group validity and norm establishment of KSSQ are suggested to provide further sound psychometric properties and practical measurement tools.

한국어판 단축형 만성질환관리 자기효능감 도구의 타당도와 신뢰도 검증 (Validity and Reliability of Korean Version of the Self-Efficacy for Managing Chronic Disease 6-Item Scale)

  • 김숙남;이현주;김소영;이나윤
    • 대한간호학회지
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    • 제51권5호
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    • pp.617-629
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    • 2021
  • Purpose: The aim of this study was to examine the validity and reliability of the Korean version of the self-efficacy for managing chronic disease 6-item scale (SECD-6-K). Methods: The English version of the Self-Efficacy for Managing Chronic Disease 6-item Scale first underwent forward and backward translation procedures. The SECD-6-K was then used to collect data from 350 adults diagnosed with chronic diseases. Content, construct, convergent, discriminant, and criterion validity were all evaluated. Reliability was assessed using Cronbach's α. SPSS 25.0 and the data were analyzed using AMOS 26.0 software. Results: The SECD-6-K consists of six items in two domains: disease management and health behavior. The results for construct, convergent, and discriminant validity were good. Exploratory factor analysis produced eigen values between 2.27 and 3.28, with factors total explained cumulative variance of 91.1%. Confirmatory factor analysis supported goodness of fit and reliability for the modified SECD-6-K model. The criterion validity also showed significant correlation with both the Patient Health Questionnaire and 12-item Short-Form Health Survey version 2. Finally, reliability was found to be excellent. Conclusion: This study identified the high reliability and validity of SECD-6-K. The SECD-6-K is an appropriate tool for determining Korean patients' self-efficacy in managing their chronic conditions. Therefore, this scale may be used in clinical settings as well as in educational and research settings.

암 환자의 영적 디스트레스 측정도구 개발 (The Development of a Tool for Assessment of Spiritual Distress in Cancer Patients)

  • 김진숙;고일선;고수진
    • 대한간호학회지
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    • 제52권1호
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    • pp.52-65
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    • 2022
  • Purpose: This study was conducted to develop a scale to measure spiritual distress in cancer patients. Methods: A total of 69 preliminary items for the spiritaul distress assessment tool (SDAT) were compiled, based on a literature review, selection of empirically relevant items through concept analysis of hybrid models, confirmation of content validity by experts, cognitive interviews, and a pretest. Self-administered questionnaires were collected between April 1 and July 31, 2018, from 225 cancer patients at four medical institutions and one nursing home. The data were analyzed using item analysis, exploratory factor analysis, convergent and discriminant validity, and Pearson correlation for criterion validity. Reliability was tested by Cronbash's α coefficient. Results: The final version of the SDAT consisted of 20 items. Five-factors, loss of peace, burden of family, avoidance of confronting death, guilt and remorse, regret for not being able to apololgize and forgive were extracted, and showed 62.8% of total variance. The factors were confirmed through convergent and discriminant validity. Criterion validity was confirmed by functional assessment chronic illness therapy spiritual well-being scale 12 (FACIT-Sp12). The overall Cronbach's α was .91, and the coefficients of each subscale ranged from .78~.83. Conclusion: The SDAT for cancer patients is valid and reliable. It is suggested that the tool can be used to measure spiritual distress in cancer patients.

자원동원성 측정도구의 신뢰도와 타당도 (Reliability and Validity of the Measurement for Assessing Resourcefulness)

  • 서순림;이은옥;이원기
    • 대한간호학회지
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    • 제28권2호
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    • pp.244-255
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    • 1998
  • The purpose of this study was to verify the reliability and validity of the Rosenbaum self-control schedule (SCS) for assessing resourcefulness in Korea and to explore the simplified scale. The study subjects consisted of 787 adults in a community. The data was collected during the period from Oct. to Dec., 1995 and analyzed as Cronbach α, item correlation with total, Pearson correlation and factor analysis with varimax rotation using SAS. Results were as follows : The mean SCS score for this sample was 17.2 and there were statistical differences for gender(men, 13.1 ; women, 20.0) on the SCS scores. The cronbachα of SCS with 36 items was .74 and when simplified with 30 items, it's coefficient alpha was .78. The translated content of the SCS was validated by two nursing faculty members and one professor of psychology. Factor analysis revealed the most parsimonious structure was obtained when six factors were extracted and subsequently rotated via the varimax criterion. There was 40.2% of total communality variance in the SCS with 36 items. The total communality variance was slightly increased to 43.4% with 30 items of the SCS. In order to reduce from 36 items to 30 items, the process excepted 6 items having low item correlation with total and low MSA(means of sampling adequacy) of factor analysis. According to factor analysis, there are six factors such as emotion control, impulse control, self-efficacy, coping with problems, pain control and satisfaction control, The SCS was found to have low, but statistically significant, correlations with social desirability and helplessness. From the above results, it can be concluded that the reliability of the SCS(inherent and simplified) was a acceptable level and its validity was reasonable when comparing it with other validity studies. To determine the usefulness the simplified scale, further study is necessary to simultaneously compare and analyze both scales for stability.

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