• The Mathematical Education
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• v.57 no.3
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• pp.215-229
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• 2018

Despite the importance of learning to do mathematical proofs, researchers have reported that not only secondary school students but also undergraduate students have difficulties in learning proofs. In this study, we introduced a new toll for learning proofs and explored the reliability and the validity of peer assessment on proofs. In the course of a university in Seoul, students were given weekly proof assignments prior to class. After solving the proofs, each student had to assess other students' proofs. The inter-rater reliabilities of weekly peer assessment was higher than .9 over 90 percent of the observed cases. To examine the validity of peer assessment, we check whether students' assessments were similar to expert assessment. Analysis showed that the equivalence has been quite high throughout the semester and the validity was low in the middle of the semester but rose by the end of the semester. Based on these results, we believe instructors can consider the application of peer assessment on proving tasks as a tool to help students learn.

• Therapeutic Science for Rehabilitation
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• v.8 no.4
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• pp.77-92
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• 2019

Objective : This study aims to obtain the validation of Korean version of HOME FAST using the translation-back translation process and to evaluate the reliability. Methods : Total three stages were conducted which includes forward translation to Korean, test for degree of understanding of translated version, back translation to English, and then review and proof reading process. 21 occupational therapists were participated in the evaluation of understanding of Korean-translated HOME FAST, then some of expressions were modified for better understanding. Korean version was went through back-translation to English. Similarity between the original version and re-translated version were evaluated. Total 75 data from community dwelling elderly group were collected to assess internal consistency. Two occupational therapists simultaneously evaluated for the inter-rater reliability. Results : 11 items of Korean-translated scale were responded as having confused meaning by occupational therapists. There was some modification on expression. In the evaluation of similarity between original version and re-translated version, 3 items were selected as dissimilar items in terms of syntax and 6 items were selected in terms of semantic similarity. After the repetitive modification process, items were obtained conceptual equivalence between two different languages. Internal consistency was .62(KR20) (p<.01) and inter-rater reliability was .97(ICC) (p<.01). Conclusion : Korean version of HOME FAST was finalized through translation-retranslation process. The conceptual equivalence was established and Korean version showed highly reliable. In further study, The modification of items reflecting Korean house and life style should be conducted.

• Physical Therapy Korea
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• v.23 no.1
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• pp.31-37
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• 2016

Background: The assessment tool developed in other countries should be translated into Korean language using rigorous methodological approaches in order to be used in Korea. Because these procedures are insufficient for establishing the cross-cultural and linguistic equivalence, the need for statistical methods is raised. The Fullerton Advanced Balance Scale was translated into Korean and the content validity was verified through the back translation method, but the reliability and validity have not yet been proven by statistical methods. Objects: The purpose of this study was to investigate the reliability and validity of the Korean version of the Fullerton Advanced Balance Scale (KFAB) by statistical methods in elderly people. Methods: A total of 97 elderly adults (39 males and 58 females) participated in this study. Internal consistency of the KFAB was measured using Cronbach's alpha and an intraclass correlation coefficient (ICC) was used to assess test-retest reliability between the two measurement sessions. Concurrent validity was measured by comparing the KFAB responses with the Korean version of the Berg Balance Scale (KBBS) using the Spearman correlation coefficient. Construct validity of the KFAB was measured using the exploratory factor analysis to evaluate the unidimensionality of the questionnaire. The significance level was set at ${\alpha}=.05$. Results: The internal consistency of the KFAB was found be adequate with Cronbach's alpha (.96), and test-retest reliability was excellent as evidenced by the high ICC (r=.996). Concurrent validity showed high correlation between the KFAB and KBBS (r=.89, p<.001). Construct validity was evaluated using exploratory factor analysis. The result from Bartlett test of sphericity was statistically significant (p<.001), and the value of Kaiser-Meyer-Olkin measure of sampling adequacy was .93. Exploratory factor analysis revealed the existence of only one dominant factor that explained 76.43% of the variance. Conclusion: The KFAB is a reliable, valid and appropriate tool for measuring the balance functions in elderly people.

• Journal of Korean Academy of Nursing
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• v.42 no.1
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• pp.76-84
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• 2012

Purpose: The purpose of this methodological study was to examine the reliability and validity of a translated Korean version of the Critical Care Pain Observation Tool (CPOT) developed for assessment of pain in critically ill nonverbal patients. Methods: A cross-sectional study design was used. Data were collected from a convenience sample of 202 critically ill patients admitted to a university hospital. Upon establishment of content and translation equivalence between the English and Korean version of CPOT, psychometric properties were evaluated. Results: The interrater reliability was found to be acceptable with the weighted kappa coefficients of .81-.88. Significant high correlations between the CPOT and the Checklist of Nonverbal Pain Indicators were found indicating good concurrent validity (r=.72-.83, p<.001). Data showed the area under the ROC curve of 0.86 with a cut-off point of 1, which resulted in 76.9% sensitivity and 88.6% specificity. The mean score of CPOT during suctioning was significantly different from that of before (t= -14.16, p<.001) or 20 minutes after suctioning (t=16.31, p<.001). Conclusion: Results of this study suggest that the CPOT can be used as a reliable and valid measure to assess pain in critically ill nonverbal patients.

• Transactions of the Korean hydrogen and new energy society
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• v.17 no.3
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• pp.255-262
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• 2006

To develop a hydrogen fueled engine with external mixture which uses in high reliability, low cost and low pressure, the single cylinder research engine with MCVVT(Mechanical Continuous Variable Valve Timing) system is developed and its basic characteristics analyzed. The MCVVT developed has high reliability and the valve timing change is possible in wide range continuously. Though the mechanical loss due to MCVVT system is increased a little, back-fire suppression research for valve overlap period is no difficulty. It's also confirmed that the hydrogen-fueled engine has lower torque and is possible high lean burn. As fuel-air equivalence ratio is high, as thermal efficiency is remarkable increasing.

• 한국연소학회:학술대회논문집
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• 2003.12a
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• pp.185-193
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• 2003

Basic flow fields of two dimensional V flames were examined as a preliminary work to study the instability of premixed flame with vorticity generation. Laminar premixed propane and methane flame were anchored by electrically heated wire to make two dimensional V flames. Flow fields were measured mainly by PIV(Particle Image Velocimetray) and the results were compared with those obtained by LDV(Laser Doppler Velocimetry) to confirm their reliability. Because the curvatures of V flames are so small, V flames were locally assumed to be inclined planar flames in gravitational field. The measured flow fields were locally compared with those of analytical solutions, which showed the qualitatively similar results. In downstream region, the vorticity fields were nearly constant except region near the center line, which support the assumption of locally one dimensional flame. Besides it was tried to find experimentally the similarity of flow fields in downstream region. Finally, stability diagram of propane and methane flames were drawn for the equivalence ratio less than one and the wide range of mean velocity.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.13 no.7
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• pp.3533-3549
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• 2019

A big database utilizes the establishing network technology, and it became an emerging trend in the computing field. Therefore, there is a necessity for an optimal and effective data distribution approach to deal with this trend. This research presents the practical perspective of designing and implementing distributed database features. The proposed system has been establishing the satisfying, reliable, scalable, and standardized use of information. Furthermore, the proposed scheme reduces the vast and recurring efforts for designing an individual system for each university, as well as it is effectively participating in solving the course equivalence problem. The empirical finding in this study shows the superiority of the distributed system performance based on the average response time and the average waiting time than the centralized system. The system throughput also overcomes the centralized system because of data distribution and replication. Therefore, the analyzed data shows that the centralized system thrashes when the workload exceeds 60%, while the distributed system becomes thrashes after 81% workload.

• Journal of Korean Critical Care Nursing
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• v.6 no.1
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• pp.1-10
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• 2013

Purpose: The purpose of this study was to examine the reliability and validity of a Korean version of the Critical Care Pain Observation Tool (CPOT) developed for assessment of pain in critically ill nonverbal patients. Methods: Data were collected from a convenience sample of 30 critically ill patients admitted to a medical ICU in a hospital. The CPOT was tested at before, during and 20 minutes after changing a position and suction. Upon establishment of content and translation equivalence between the English and Korean version of CPOT. Results: The interrater reliability was found to be acceptable with the kappa coefficients of .76-1. The construct validity of the pain scores were increased from 0.43 to 2.5 in changing a position (t=-8.60, p<.001)and 0.1 to 3.23 (t=-9.36, p<.001) in suctioning. The pain scores were decreased from 6.06 to 4.01 in changing a position (t=-10.19, p<.001) and 6.45 to 4.13 (t=-10.39, p<.001) in suctioning. The concurrent validity the correlations between pain scores and physiological indicators, and a increased in Heart rate before and after changing a position (r=.65, p<.001). Conclusion: The CPOT can be used as a reliable and valid measure to assess pain in critically ill nonverbal a medical ICU patients.

• Fire Science and Engineering
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• v.23 no.4
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• pp.130-136
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• 2009

The present study has been performed to evaluate the reliability of the fire field model (FDS version 5.2) with yield rate concept of combustion products. The CO and smoke density predicted by FDS model was directly compared with measurement in a reduced scale ISO-9705 room. The GER (global equivalence ratio) concept was used to characterize the CO and smoke density with ventilation condition in the fire compartment. The FDS model tends to under-predict CO concentration and smoke density than those of measurement for the under-ventilated conditions. Also, the discrepancy between predicted and measured result increases as GER increases. In order to improve the reliability of the fire model for performance evaluation of fire safety, the fire model is necessary to be validated in various fire cases as well as develop detailed physical model.

• Particle and aerosol research
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• v.19 no.1
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• pp.13-20
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• 2023

The Asian dust observation network operates β-ray attenuation samplers to measure PM₁₀ concentrations. In addition, equivalence evaluation and accuracy inspection(Precision Tests) are conducted every year for the reliability of data. β-ray attenuation samplers(16 units) were comparatively observed from May to June 2020 and from July to December 2021. During the observation period, the average daily temperature was the lowest at 6.4℃ in December and the highest at 27.3℃ in August. The average daily humidity ranged from 60% to 100%, but the average daily humidity was over 75% from July to September. The minimum value of the PM₁₀ Gravimetric method was 5.0 ㎍/m³, the maximum value was 53.4 ㎍/m³, and the average value was 17.8 ㎍/m³. The equivalence evaluation results of the PM₁₀ Gravimetric method and β-ray attenuation samplers satisfied the criteria (slope: 1±0.1, intercept: 0±0.5). A relative error analysis between the PM₁₀ Gravimetric method and β-ray attenuation samplers equipment showed that the relative error increased when the concentration was low and the temperature and humidity were high. In addition, in the β-ray attenuation samplers 5-minute interval observation data in May 2020, a relatively large Standard devication was shown as an average maximum ±23.4 ㎍/m³ and a minimum ±15.2 ㎍/m³. At standard deviations of 10% and 90%, equipment with high variability (deviation) was measured at 6 ㎍/m³and 61 ㎍/m³, and equipment with low variability was measured at 12 ㎍/m³ and 47 ㎍/m³. It was confirmed that concentration differences occurred due to differences in variability for each equipment.