• Journal of the Korean Ceramic Society
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• v.51 no.5
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• pp.453-458
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• 2014

SiC and its composites have been considered for use as nuclear fuel cladding materials of pressurized light water reactors. In this study, a $SiC_f$/SiC composite as a constituent layer of SiC triplex fuel cladding was fabricated using a chemical vapor infiltration (CVI) process in which tubular SiC fiber preforms were prepared using a filament winding method. To enhance the matrix density of the composite layer, winding patterns, deposition temperature, and gas input ratio were controlled. Fiber arrangement and porosity were the main parameters influencing densification behaviors. Final density of the composites decreased as the SiC fiber volume fraction increased. The CVI process was optimized to densify the tubular preforms with high fiber volume fraction at a high $H_2$/MTS ratio of 20 at $1000^{\circ}C$; in this process, surface canning of the composites was effectively retarded.

• Research in Community and Public Health Nursing
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• v.21 no.2
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• pp.156-168
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• 2010

Purpose: The purpose of this study was to construct a questionnaire to assess male workers' sobriety behavior based on Ajzen's Theory of Planned Behavior (TPB). Methods: A primary questionnaire with 56 questions was constructed based on literature review and structured interview with male workers. The Content Validity Index (CVI) was evaluated by a group of experts, construct validity was tested by principle component analysis, and reliability was evaluated by Cronbach's ${\alpha}$ and the test-retest reliability test. Results: Fifty two questions showed higher than .8 of CVI. Four factors explained 78.71% of the total variance among items for sobriety intention and direct measure, and six factors explained 67.99% of the total variance among indirect measure items and those factors coincided with the variables of TPB in factor analysis. Cronbach's ${\alpha}$ of this questionnaire was .873 and the result of test-retest reliabilty test was relatively reliable. A total of 41 items with 7-point scale were constructed in the final version. Conclusion: This questionnaire was valid and reliable to measure sobriety behavior based on TPB in male workers. It can be useful to evaluate the result of a sobriety program for male workers.

• Journal of the Korean Society of Physical Medicine
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• v.11 no.2
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• pp.103-114
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• 2016

PURPOSE: The purpose of this study was first to develop a Korean version of pediatric functional muscle testing for children with a motor developmental disorder who have a communication problem and who are aged below five years, and also to verify the content validity. METHODS: First, the preliminary study was conducted to verify the reliability of pediatric functional muscle testing, developed by Venita in Korea. Based on the results of the study, the primary evaluation items were selected and modified. Second, the first test of content validity was conducted through a panel discussion, and a second investigation of content validity was carried out by utilizing the Item Content Validity Index (I-CVI). In this study, we selected only 0.78 or more items from I-CVI. RESULTS: Based on the results of the preliminary study, 19 primary evaluation items were selected. Based on the results of the first and second content validity tests, 15 tertiary evaluation items for the Korean version of pediatric functional muscle testing were determined. CONCLUSION: This study developed a new Korean version of pediatric functional muscle testing and suggested that it will be a useful tool to measure muscle strength for Korean children with a motor developmental disorder and a communication problem, aged below five years.

• Journal of the Korean Ceramic Society
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• v.45 no.2
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• pp.132-137
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• 2008

The main purpose of this study is enhancing the filtering efficiency, performance and durability of filter by growing SiC whiskers on cordierite honeycomb substrate. The experiment was performed by Chemical Vapor Infiltration (CVI) in order to control pore morphology of substrate. Increasing the mechanical strength of porous substrate is one of important issues. The formation of "networking structure" in the pore of porous substrate increased mechanical strength. The high pressure gas injection to the specimen showed that a little of whiskers were separated from substrate but additional film coating enhanced the stability of whisker at high pressure gas injection. Particle trap test was performed. More nano-particle was trapped by whisker growth at the pore of substrate. Therefore it is expected that the porous cordierite which deposited the SiC whisker will be the promising material for the application as filter trapping the nano-particles.

• Journal of the Semiconductor & Display Technology
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• v.14 no.2
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• pp.61-65
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• 2015

SiC composite materials are usually used to very high temperature condition such as thermal protection system materials at space vehicles, combustion chambers or engine nozzles because they have high specific strength and good thermal properties at high temperature. One of the most widely used fabrication methods of SiC composites is the chemical vapor infiltration (CVI) process. During the process, chemical gases including Si are introduced into porous preform which is made by carbon fibers for infiltration. Since the processes take a very long time, it is important to reduce the process time in designing the reactors and processes. In this study, both the gas flow and heat transfer in the reactors during the processes are analyzed using a computational fluid dynamics method in order to design reactors and processes for uniform, high quality SiC composites. Effects of flow rate and heater temperature as process parameters to the infiltration process were examined.

• Journal of the Korean Ceramic Society
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• v.55 no.4
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• pp.392-399
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• 2018

$C_f/SiC$ composites were prepared via a process combining chemical vapor infiltration (CVI) and precursor infiltration pyrolysis (PIP), wherein silicon carbide matrices were infiltrated into 2.5D carbon preforms. The obtained composites exhibited porosities of 20 vol % and achieved strengths of 244 MPa in air at room temperature and 423 MPa at $1300^{\circ}C$ under an Ar atmosphere. Carbon fiber pull-out was rarely observed in the fractured surfaces, although intermediate layers of pyrolytic carbon of 150 nm thickness were deposited between the fiber and matrix. Fatigue fracture was observed after 1380 cycles under 45 MPa stress at $1000^{\circ}C$. The fractured samples were analyzed by transmission electron microscopy to observe the distributed phases.

• Journal of Korean Clinical Nursing Research
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• v.18 no.2
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• pp.307-316
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• 2012

Purpose: The purpose of this study was to develop and test psychometric properties the Korean version of the End-Stage Renal Disease Adherence Questionnaire (KESRD-AQ). The ESRD-AQ, a 46-item, multidimensional, self-administrated questionnaire which was developed to assess treatment adherence to hemodialysis (HD) attendance, medications, fluid restrictions, and diet prescription among patients on maintenance hemodialysis, has been validated. Methods: The KESRD-AQ was developed by performing both translation and backtranslation. The content validity and test- retest reliability of the KESRD-AQ were evaluated by establishing item-level content validity index (I-CVI) and intra-class correlation coefficients (ICC), respectively. Construct validity was assessed by adopting a known-group analysis comparing adheres and non-adherers using Mann-Whitney U Test. Results: 41 Korean-American patients with ESRD on HD from 3 outpatient dialysis centers in California participated in the study. The KESRD-AQ showed excellent content validity (average I-CVI=.96) and test-retest reliability (ICC=.917, p=.004). The construct validity indicated that the KESRD-AQ distinguished adheres and non-adheres (p=.02~.047). Conclusion: The KESRD-AQ is a valid and reliable instrument to measure treatment adherence.

• KIPS Transactions on Software and Data Engineering
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• v.5 no.7
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• pp.333-338
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• 2016

This study is to estimate proximity without direct measurement of the weight of fresh ginseng. For this work, we developed a ginseng image acquiring instrument and obtained 126 ginseng images using the instrument. Image analysis and parameter extraction process was used C language based Labwindows/CVI development tools and open source library OpenCV. Estimation formula is made by weighing the sample with image analysis of fresh ginseng. We analyzed the correlation between the pixel number and the weight of ginseng using a linear regression approach. It was obtained a strong positive correlation coefficient of 0.9162 with a linearity value.

• Journal of Korean Clinical Nursing Research
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• v.25 no.2
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• pp.179-188
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• 2019

Purpose: The purpose of this study was to develop a valid Adult Fall Assessment Scale Korean version (FAS-K) for inpatients in general hospitals in Korea. Methods: This a 14 item FAS-K was developed based on a review of national and international research and expert opinions in related field. Interrater reliability of FAS-K was analyzed using the ICC (Intraclass Correlation Coefficients). To examine the validity of FAS-K, a CVI (Content Validity Index), the Pearson correlation coefficients between FAS-K and two widely used scales, the Morse Fall Scale (MFS) and the Johns Hopkins Hospital Fall Risk Assessment Tool (JHFRAT), and the Mann-Whitney test were used. Results: The ICC was .958. The CVI ranged from .70 to 1.00. The FAS-K was significantly associated with the MFS (r=.74, p<.001) and with the JHFRAT (r=.87, p<.001), verifying the concurrent validity of FAS-K. As for the construct validity of FAS-K, significant differences between the fall and non-fall groups were found not only in the MFS (Z=-3.23, p=.001) but also in the FAS-K (Z=-3.10, p=.002). Conclusion: The findings indicate that the FAS-K is a reliable fall risk assessment tool with high validity.

• Journal of the Korea Society of Computer and Information
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• v.25 no.12
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• pp.93-100
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• 2020

This study aims to design and develop effective digital contents to improve the ability for artificial intelligence literacy. First, we defined AI literacy and analyzed the competencies required for artificial intelligence literacy. After selecting the educational elements for AI ability, we composed 10 educational programs. To confirm the appropriateness of designed contents, we verified through content validity test by 10 experts. The CVI value was over 0.75, which was highly valid. The developed content was installed on the online system and applied to 55 AI beginners for 4 weeks. The learners showed a positive result of at least 3.85 in the items of content difficulty, understanding, effectiveness, and learning challenge. As a result of this analysis, we can see that the developed content is positive for helping many people understand AI and improving AI literacy.