• 한국과학교육학회지
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• 제15권1호
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• pp.92-103
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• 1995

Since the late of 1960,s, the improvement of science inquiry skills has been one of the most important goals in secondary science education. To achieve this goal, it is essential to develop a valid and reliable instrument for evaluating science inquiry skills. The purpose of this study is to develop a valid and reliable instrument for evaluating science inquiry skills for high school students. The instrument is developed through R & D procedure, which includes two field trials of the instrument. This study has formed a clear definition of the elements of science inquiry skills (formulating a hypothesis, controlling variables, designing an experiment, numeric calculation, graphing experimental data, inference, determining relationship, determining causalities, predicting experimental results , drawing a conclusion, formulating a generalization or model), and established the goals of assessment and developed the items of assessment. The instrument, Test of Earth Science Inquiry Skills, consists of 33 items which measure 11 science inquiry skills. There are content-free items for each science inquiry skills. This study has selected 11 science inquiry skills which are considered appropriate for being evaluated by paper-and-pencil test with SIEI (Hur,1984). The content validity of items, objectivity of the scoring keys and clarity of the items were checked by six experienced specialists in science education. At the same time, the two field trials has been executed and produced the reliability of the instrument, item difficulty index, and the effectiveness of distracters. The first field trial was performed using a sample of 304 high school students, and the second one using a sample of 872 high school students. Because the content validity is 84 % and the reliability (K-R 20) is 0.84, the developed instrument in this study is considered valid and reliable. The difficulty index is 49.4 %, answer ratio 59.1 %, the discrimination index 0.47 and the effectiveness of distracters evenly distributed, which also suffice the criteria of good instrument. The developed instrument in this study can diagnosis the well-developed science inquiry skills and the ill-developed science inquiry skills of the students, and trace the degree of the improvement of science inquiry skills.

• International Journal of Concrete Structures and Materials
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• 제9권2호
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• pp.185-206
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• 2015

This paper presents statistical models developed to study the influence of key mix design parameters on the properties of lightweight self-consolidating concrete (LWSCC) with expanded shale (ESH) aggregates. Twenty LWSCC mixtures are designed and tested, where responses (properties) are evaluated to analyze influence of mix design parameters and develop the models. Such responses included slump flow diameter, V-funnel flow time, J-ring flow diameter, J-ring height difference, L-box ratio, filling capacity, sieve segregation, unit weight and compressive strength. The developed models are valid for mixes with 0.30-0.40 water-to-binder ratio, high range water reducing admixture of 0.3-1.2 % (by total content of binder) and total binder content of $410-550kg/m^3$. The models are able to identify the influential mix design parameters and their interactions which can be useful to reduce the test protocol needed for proportioning of LWSCCs. Three industrial class ESH-LWSCC mixtures are developed using statistical models and their performance is validated through test results with good agreement. The developed ESH-LWSCC mixtures are able to satisfy the European EFNARC criteria for self-consolidating concrete.

• Safety and Health at Work
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• 제6권2호
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• pp.97-103
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• 2015

Background: This paper describes the development of a scale for measuring safety climate. Methods: This study was conducted in six manufacturing companies in Iran. The scale developed through conducting a literature review about the safety climate and constructing a question pool. The number of items was reduced to 71 after performing a screening process. Results: The result of content validity analysis showed that 59 items had excellent item content validity index (${\geq}0.78$) and content validity ratio (> 0.38). The exploratory factor analysis resulted in eight safety climate dimensions. The reliability value for the final 45-item scale was 0.96. The result of confirmatory factor analysis showed that the safety climate model is satisfactory. Conclusion: This study produced a valid and reliable scale for measuring safety climate in manufacturing companies.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2004년도 추계 학술발표회 제16권2호
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• pp.679-682
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• 2004

Air void systems in hardened concrete has an important influence on concrete durability such as freeze-thaw resistance, water permeability, surface scaling resistance. Linear traverse method and point count method described at ASTM is the routine analysis of the air void system that have been widely used to estimate the spacing factor in hardened concrete. Recently, many concretes often have a spacing factor higher than the generally accepted $200-250{\mu}m$ limit for the usual range of air contents. This study is proposed to estimate the matrix spacing factor by calculation of simplicity. The matrix spacing factor needs two parameters that are air content and numbers of air voids in the hardened concrete. Those are obtained from the standard air-void system analysis of the ASTM C 457. The equation is valid for all values of paste-to-air ratio because the estimation of paste content is unnecessary at the using ASTM C 457. The matrix spacing factor yields a similar estimate of the standard spacing factor.

• Computers and Concrete
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• 제17권4호
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• pp.477-488
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• 2016

This paper aims to model the effects of five different variables which includes: cement content (C), the steel fiber amount (F), the silica fume amount (SF), the superplasticizer (SP), the silica fume amount (SF), and the water to cementitious ratio (w/c) on 28 days flexural toughness of Ultra High Performance Concrete (UHPC) as well as, a study on the variable interactions and correlations by using analyze of variance (ANOVA) and response surface methodology (RSM). The variables were compared by fine aggregate mass. The model will be valid for the mixes with 0.18 to 0.32 w/c ratio, 4 to 8 percent steel fiber, 7 to 13 percent cement, 15 to 30 percent silica fume, and 4 to 8 percent superplasticizer by fine aggregate mass.

• 산업기술연구
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• 제25권A호
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• pp.39-47
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• 2005

Air void systems in hardened concrete has an important influence on concrete durability such as freeze-thaw resistance, water permeability, surface scaling resistance. Linear traverse method and point count method described at ASTM are the routine analysis of the air void system that have been widely used to estimate the spacing factor in hardened concrete. Recently, many concretes often have a spacing factor higher than the generally accepted $200-250{\mu}m$ limit for the usual range of air contents. This study is proposed to estimate the plane spacing factor by calculation of simplicity. The plane spacing factor need two parameters that are air content and numbers of air voids in the hardened concrete. Those obtained from the standard air-void system analysis of the ASTM C 457. The equation is valid for all values of paste-to-air ratio because the estimation of paste content is unnecessary at the using ASTM C 457. The plane spacing factor yields a similar estimate of the standard spacing factor.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제22권6호
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• pp.554-564
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• 2019

Purpose: This study verified the reliability and validity of the Diet Quality Index for Indian children (DQIIC). Methods: The study sample included 100 school going boys and girls (7-9 years). The dietary behavior of children was studied using a questionnaire and 24-hour dietary recall. The DQIIC comprises 21 items which aimed to assess the diet of Indian children on the basis of variety, adequacy of consumption of dietary components, and moderation in the amount of nutrients that are associated with diseases and dietary habits. The reliability of the DQIIC was assessed using the split half method, Cronbach's alpha, and test retest reliability. Content validity was evaluated using content validity ratio (CVR). Results: The intake of iron was found to be less than the recommended dietary allowances. There was frequent consumption of empty calorie packaged foods and higher than the recommended amount of sodium. Reliability of the DQIIC was 0.85 by split half method and the correlation coefficient for test retest reliability was 0.87. Cronbach's alpha was 0.62 and CVR was 0.85 for this index. Most of the children fell in the moderately healthy category. Conclusion: The DQIIC is a reliable and valid tool to assess the diet quality of Indian children between 7-9 years.

• 한국버섯학회지
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• 제20권4호
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• pp.270-273
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• 2022

느타리 재배에서 비트펄프를 대체하여 밀짚펠렛을 첨가한 결과는 다음과 같다. 처리 간 화학성은 pH 4.8~5.5, 총 탄소함량 45.9~46.5%, 총질소함량 1.5~1.7%로 밀짚펠렛의 대체첨가량이 증가할수록 pH는 높아지고 총탄소함량과 총질소함량은 대조구와 유사하거나 낮아지는 경향이 있었으며, 탄질비는 27.8~31.0로 대조구에 비해 유사하거나 높게 나타났다. 처리 간 균사생장은 '흑타리'의 경우 밀짚펠렛을 20% 대체첨가한 C처리구에서 88.2 mm로 대조구(83.7 mm)에 비해 빠른 균사생장을 보였고, '수한1호'는 모든 처리구에서 70.3~79.6 mm로 대조구(69.1 mm)에 비해 균사생장이 빨랐으며, 밀짚펠렛의 첨가량이 증가할수록 균사생장이 빠른 경향을 보였다. 균사밀도는 처리 간 뚜렷한 차이를 보이지 않았다. 자실체는 '흑타리'의 경우 밀짚펠렛을 10% 대체첨가한 A처리구에서 병 당 수량 177.1 g, 병 당 유효경수 22.5개로 대조구와 대등하였고, '수한1호' 또한 A처리구에서 병당 수량 151.2 g, 병 당 유효경수 14.0개로 대조구와 대등한 수준이었다. 따라서 느타리 재배 시 비트펄프를 대체하기 위한 밀짚펠렛의 첨가량은 10%가 적절함을 확인하였으며, 첨가비율을 높이기 위해 지속적인 연구가 필요할 것으로 판단된다.

• Asian Pacific Journal of Cancer Prevention
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• 제17권9호
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• pp.4341-4347
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• 2016

Background: Patient safety is one of the key components of nursing care for cancer cases. Valid and reliable context-based instruments are necessary for accurate evaluation of patient safety in oncology units. The aim of the present study was to develop and evaluate the psychometric properties of the Patient Safety Violation Scale in medical oncology units in Iran. Materials and Methods: In this methodological study, a pool of 58 items was generated through reviewing the existing literature. The validity of the 58-item scale was assessed through calculating impact score, content validity ratio, and content validity index for its items as well as conducting exploratory factor analysis. The reliability of the scale was evaluated by assessing its internal consistency and testretest stability. Study sample consisted of 300 oncology nurses who were recruited from thirteen teaching hospitals affiliated to Tehran University of Medical Sciences, Tehran, Iran. Results: Sixteen items were excluded from the scale due to having low impact scores, content validity ratios, or content validity indices. In exploratory factor analysis, the remaining 42 items were loaded on five factors including patient fall, verification of patientidentity, harm during care delivery, delay in care delivery, and medication errors. These five factors explained 62% of the total variance. The Cronbach's alpha of the scale and the test-retest interclass correlation coefficient were equal to 0.933 and 0.92, respectively. Conclusions: The 42-item Patient Safety Violation Scale is a simple and short scale which has acceptable validity and reliability. Consequently, it can be used for assessing patient safety in clinical settings such as medical oncology units and for research projects.

• Safety and Health at Work
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• 제9권3호
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• pp.296-307
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• 2018

Background: Safety culture, acting as the oil necessary in an efficient safety management system, has its own weaknesses in the current conceptualization and utilization in practice. As a new approach, resilience safety culture (RSC) has been proposed to reduce these weaknesses and improve safety culture; however, it requires a valid and reliable instrument to be measured. This study aimed at evaluating the reliability and validity of such an instrument in measuring the RSC in sociotechnical systems. Methods: The researchers designed an instrument based on resilience engineering principles and safety culture as the first instrument to measure the RSC. The RSC instrument was distributed among 354 staff members from 12 units of an anonymous petrochemical plant through hand delivery. Content validity, confirmatory, and exploratory factor analysis were used to examine the construct validity, and Cronbach alpha and test-retest were employed to examine the reliability of the instrument. Results: The results of the content validity index and content validity ratio were calculated as 0.97 and 0.83, respectively. The explanatory factor analysis showed 14 factors with 68.29% total variance and 0.88 Kaiser-Meyer-Olkin index. The results were also confirmed with confirmatory factor analysis (relative Chi-square = 2453.49, Root Mean Square Error of Approximation = 0.04). The reliability of the RSC instrument, as measured by internal consistency, was found to be satisfactory (Cronbach ${\alpha}=0.94$). The results of test-retest reliability was r = 0.85, p < 0.001. Conclusion: The results of the study suggest that the measure shows acceptable validity and reliability.