• Journal of the Korea Institute of Military Science and Technology
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• v.26 no.2
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• pp.113-121
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• 2023

High-precision lasers and anti-aircraft radars are the main equipment to protect the Korean Peninsula, and require preemptive maintenance before signs of failure. Of the key components in the drive sector, bearings do not have a fault alarm function. Therefore, the technology for diagnosing defects in bearings before the performance degradation of equipment occurs is becoming more important. In this paper, for the experimental analysis, we measured the acceleration of the four sets of the same lot using acceleration sensors. Through periodic measurements, the factors that changed until the bearing stopped rotating were analyzed. To determine the replacement time, the main factors and threshold values of the bearing signal were analyzed. The error of the theoretical and experimental analysis results of the defect frequency was within 2.8 %, and the validity of the theoretical analysis results could be confirmed. Based on the results, it is possible to remotely transmit trouble alerts to users through the system check function.

• Journal of Drive and Control
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• v.19 no.2
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• pp.36-44
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• 2022

Hydrogen energy as an alternative source of energy has been receiving tremendous support around the world, and research is being actively conducted accordingly. However, most of the studies focus on hydrogen storage tanks and only are few studies on interpreting the hydrogen filling system itself. In this study, with reference to SAE J2601, a hydrogen fueling protocol, a simulation model was developed that can confirm the behavior of the vehicle's internal tank during hydrogen fueling. With respect to factors such as fuel supply temperature, ambient temperature, and pressure increase rate, the developed model can check the change of temperature and pressure in the tank and the state of hydrogen charging during hydrogen fueling. The validity of the developed simulation model was confirmed by comparing the simulation results with the experimental results presented in SAE J2601.

• Journal of Software Assessment and Valuation
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• v.13 no.1
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• pp.15-21
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• 2017

Analyzing a software package which is consisted of big numbers of files takes enormous costs and time. Therefore, SPDX (Software Package Data Exchange) working group collaborate with Linux Foundation published a software information(metadata) specification: SPDX. On the first half of 2017, the specification contains seven chapters and 66 items, according to Ver 2.1 of SPDX spec. It prefers Tag/Value or RDF forms but also supports spreadsheet form. In this paper, we introduce SPDX parsing & validation tools to check the validity of SPDX document. We'll develop SPDX document generator to manage software package more efficiently for our next target.

• Advances in nano research
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• v.17 no.1
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• pp.19-32
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• 2024

Functionally graded-carbon nanotube (FG-CNT) is expected to be a new generation of materials with a wide range of potential applications in technological fields such as aerospace, defense, energy, and structural industries. In this paper, an exact finite strip method for functionally graded-carbon nanotube sandwich plates is developed using first-order shear deformation theory to get the exact natural frequencies of the plates. The face sheets of the plates are made of FG-CNT with continuous and smooth grading based on the power law index. The equations of motion have been generated based on the Hamilton principle. By extracting the exact stiffness matrix for any strip of the sandwich plate as a non-algebraic function of natural frequencies, it is possible to calculate the exact free vibration frequencies. The accuracy and efficiency of the current method is established by comparing its findings to the results of the literature works. Examples are presented to prove the efficiency of the generated method to deal with various problems, such as the influence of the length-to-height ratio, the power law index, and a core-to-face sheet thickness of the single and multi-span sandwich plates with various boundary conditions on the natural frequencies. The exact results obtained from this analysis can check the validity and accuracy of other numerical methods.

• Journal of the Korean Data and Information Science Society
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• v.26 no.3
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• pp.707-714
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• 2015

The SF-36 is the most common instrument to check the quality of life for dialysis patients with chronic renal failure. However, there were too much burden for them to answer 36 items of it. So we purposed to develop the RFQoL-K reduced type of the SF-36. Participants who had newly registered for dialysis were enrolled in 29 medical centers during 45months from 2009. We developed the RFQoL-K through 355 people who applied the SF-36 at 3 and 12 months after registration and then checked it's internal validity. External validity about it was checked via 411 people who answered only one time survey after registration. In conclusion, the RFQoL-K had total 14 items which was consisted of 8 items on physical factors and 6 items on mental factors from the SF-36. The RFQoL-K summary scores explained 91-93% of the SF-36 summary scores. The RFQoL-K was well reflected SF-36 because the correlation and the internal consistency between two tools were very high 0.96 to 0.98 and 0.96 to 0.98 respectively.

• Journal of vocational education research
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• v.33 no.3
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• pp.105-125
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• 2014

The purposes of this study are to develop the standardized tests of career preparation behavior of career preparation behavior for college students. For these, the 'Career Preparation Behavior Scale for College Students' which was developed in 2011 was reviewed and revised. After 609 students were involved and analyzed for the pretest, 1,244 subjects were collected by taking into account gender, grade, major, and location of colleges for developing a standardized test. The Career Preparation Behavior Scale consisted of 3 subareas and 30 items: 11 items for learning area, 12 items for counseling and information collecting area, 7 items for employment action area. The levels of reliabilities, construct validity, discriminant validity, and the concurrent validity were relatively high. Also, the suitability index of the structural model was analyzed to check the structural significance. The degree of career reparation behavior among norm groups was increased in general according to the grades. Scores of students majoring in humanities and social sciences received significantly high scores compared with those of majoring in science and technology or in art and music. But the levels of satisfaction on career preparation behavior were no difference according to gender, grade, and major. 'The Standardized Career Preparation Behavior Scale for College Students' would be used for conducting career education or programs for college students in the future.

• Journal of the Society of Disaster Information
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• v.19 no.1
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• pp.195-203
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• 2023

Purpose: This study intends to check validity of tools for awareness of Business Continuity through measurement and analysis on the sub factors of Business Continuity by employees of railway-related organizations. Method: Based on the preceding study, sub factors of the awareness of Business Continuity are divided into 7 and the total of 29 questions were delivered to employees of railway-related organizations for investigation and analysis through the online survey tool. Result: According to EFA result, the number of factors of awareness of Business Continuity based on the theoretical ground was reduced to 7 and the total coefficient of determination was 82.616%. Checking the questions by factor, all the questions were loaded as intended. Conclusion: Validity of measurement tools of Business Continuity whose sub factors are the Context of Organization, Leadership, Planning, Operation, Support, Performance evaluation, and Improvement for railway organizations were secured through the Exploratory Factor Analysis of this study. As for the further tasks, studies on the structural relationship among internalization of business continuity, organization effectiveness, learning support environment, etc are required.

• Korean Journal of School Psychology
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• v.15 no.3
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• pp.399-431
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• 2018

The purpose of this study was to summarize the empirical literature on implementation of positive behavior support (PBS) within a multi-tiered system of supports in American and Korean schools and to compare its key features and outcomes in an attempt to suggest future directions for development of a Korean school-wide PBS model and implementation manuals as well as directions for future research. Twenty-four American articles and 11 Korean articles (total 35 articles) that reported the outcomes of implementation of PBS at a tier 1 and/or tier 2, or tier 3 level and that met established inclusion criteria were analyzed using systematic procedures. Comparisons were made in the areas of key features and outcomes of PBS in addition to general methodology (e.g., participants, design, implementation duration, dependent measures) at each tier of PBS. The results indicated that positive outcomes for student behavior and other areas were reported across tiers in all American and Korean studies. At the tier 1 level, teaching expectations and rules were the primary focus of PBS in American and Korean schools. However, Korean schools focused on modifying the school and classroom environments and teaching social skills whereas American schools focused on teacher training on standardized interventions or curricular by experts and teacher support during implementation of PBS. At the tier 2 level, more American studies reported implementation of tier 2 interventions within school-wide PBS, and Check/In Check/Out (CICO) was found to be the most commonly used tier 2 intervention. The results also indicated that in comparison to Korean schools, American schools were more likely to use systematic screening tools or procedures to identify students who need tier 2 interventions and more likely to promote parental involvement with implementing interventions. At the tier 3 level, more Korean studies reported the outcomes of individualized interventions, but more American studies reported that designing individualized intervention plans based on comprehensive functional behavior assessment results and establishment of systematic screening systems were focused when implementing individualized interventions. Furthermore, few Korean studies reported the assessment of procedural integrity, social validity, and contextual fit in implementing PBS across tiers, indicating the need for development of valid instruments that could be used in assessing these areas. Based on these results, limitations of the study and suggestions for future research are discussed.

• Journal of Christian Education in Korea
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• v.64
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• pp.323-345
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• 2020

This study investigated the recognition and difficulty of Christian early childhood education curriculum of Christian early childhood education by analyzing cases of Christian early childhood curriculum experienced by 10 Christian early childhood teachers with more than 4 years of experience in the metropolitan area. From April 4 to June 24, 2018, data were collected by transcribing through a total of 22 interviews: individual interviews (20 times) and group interviews (2 times). In order to categorize the interview data, derive the core categories, and increase the accuracy and validity of data interpretation, it was sent to the study participants for member check and verified by two early childhood education experts. As a result, the perception and difficulty of Christian early childhood teachers' perceptions and difficulties in the Christian curriculum were analyzed as 'Applying Church Education to Nuri Course', 'Applying Nuri Course to Church Education', and 'Learners Understanding for Integration of Church Education and Nuri Course' did. It is hoped that the understanding of the Christian early childhood curriculum will be helped through the recognition and difficulty of the Christian early childhood curriculum experienced by Christian early childhood teachers, and will be provided as basic data for finding a desirable Christian early childhood curriculum.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.46 no.4
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• pp.371-382
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• 2020

There have been continuous attempts to quantify sensory attributes of cosmetic products by measuring relevant physical properties. The most representative method to evaluate stickiness is to measure axial force using texture analyzer. Stickiness is known to correlate with AUC which abbreviates area under curve in the obtained axial force curve as a function of time. Recently, Normandie University research group developed in vivo stickiness evaluation method considering the characteristics of skin along with established evaluation method[8]. Based on the study, we tried to optimize in vivo stickiness evaluation method especially for cosmetic creams. The experiment was carried out on 5 different facial creams products by changing the amount and the times of rolling of creams, and the shape and material of probes. Based on the results of the sensory evaluation, the most consistent conditions were established as the optimal evaluation method. As a result, applying 70 μL of cream and rubbing 10 times for 7 s inside the 3.4 cm circle were judged to be suitable. As for the probes, spherical metallic probe was more proper due to its reproducibility. We conducted the settled method on 10 subjects to check its validity. Although the absolute values of AUC differed depending on the individuals, the AUC values were all ranked the same. Finally, for the standardization of stickiness of AUC, polyvinylpyrrolidone (PVP) was set as a reference material and we measured AUC of its aqueous solution by changing concentration. Then, the degree of stickiness recognition for 5 different creams was surveyed to check the correlation between AUC and stickiness.