• Journal of the Institute of Convergence Signal Processing
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• v.2 no.3
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• pp.86-92
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• 2001

Position controls are very important in semiconductor manufacturing devices, machine tools, precision measuring instruments, etc. to measure the distance of movement of moving objects in minute units and the accuracy of measurement for the moving distance in these devices affect the performance of the whole devices. Therefore, in those precision instruments, a sensing device that can measure the distance of movement with high-precision resolution is required. Thus an optical encoder that has such advantages as easy digital interface, economical price, and a resolution similar to that of laser interferometers can be used. In this paper, a interferometer-type linear scale with easy digital interface and high-resolution has been set up and measured the distance of movement based on the diffraction principle. Interference signals produced in this optical setup of the linear scale have beers digitalized through fabricated photodetectors and designed signal processing circuits. A resolution of 0.5${\mu}{\textrm}{m}$ is acquired from the experimental interferometer-type linear scale without for the movement of scales any additional dividing circuits. It is shown that from this experiment a high-resolution distance measurement device can be designed by a simple optical setup.

• Proceedings of the Korea Water Resources Association Conference
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• 2019.05a
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• pp.154-154
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• 2019

Characterization of reliable field-scale root-zone soil moisture (RZSM) variability contribute to effective hydro-meterological monitoring. Although a promising cosmic-ray neutron probe (CRNP) holds the pontential for field-scale RZSM measurement, it is often restricted at deeper depths due to the non-unique sensitivity of CRNP-measured fast neutron signal to other hydrogen pools. In this study, a merging framework relied on coupling cosmic-ray soil moisture with a representative additional RZSM, was introduced to scale shallower CRNP effective depth to represent root-zone layer. We tested our proposed framework over a densely vegetated region in South Korea covering a network of one CRNP and nine in-situ point measurements. In particular, cosmic-ray soil moisture and ancillary RZSM retrieved from the most time stable location were considered as input datasets; whereas the remaining point locations were used to generate a reference RZSM product. The errors between these two input datasets and the reference were forecasted by a linear autoregressive model. A linear combination of forecasts was then employed to compute a suitable weight for merging two input products from the predicted errors. The performance of merging framework was evaluated against reference RZSM in comparison to the two original products and a commonly used exponential filter technique. The results of this study showed that merging framework outperformed other products, demonstrating its robustness in improving field-scale RZSM. Moreover, a strong relationship between the quality of input data and the performance merging framework in light of CRNP effective depth variation has been also underlined via the merging framework.

• The Journal of the Korea Contents Association
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• v.21 no.8
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• pp.608-618
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• 2021

The aim of this study was to verify the feasibility and reliability of the program outcome indirect measurement tool developed for nursing college students in Korean. 396 nursing students from 5 nursing colleges participated in this study, data were collected from November 22 to December 10, 2019. Data analysis was conducted using the IBM Statistics SPSS 21.0 and AMOS 21.0 programs to analyze item analysis, exploratory and confirmatory factor analysis. As a result of the item analysis, all 79 items were selected for factor analysis. In the exploratory factor analysis, five items that were loaded with other factors were deleted. The final factor loading range was from .37 to .86, and the cumulative explanatory variance for 12 factors was 71.71%. No items were deleted as a result of the confirmatory factor analysis, and the final scale was consisted of 74 items. The average score for scale was 3.78 and Cronbach' α was .98. The feasibility and reliability of the program outcome indirect measurement tool have been verified through this study. Therefore it can be used as a more standardized indirect measurement tool for nursing college students.

• Computational Structural Engineering
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• v.25 no.1
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• pp.13-16
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• 2012

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.10a
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• pp.99-99
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• 2003

• Proceedings of the Korean Nuclear Society Conference
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• 2002.05a
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• pp.445.2-445
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• 2002

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.2
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• pp.130-143
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• 2019

The purpose of this study is to identify factors of 25~36 months old infant's happiness and to develop a scale to measure infant happiness. The subjects were 250 infants aged 25~36 months. The results of this study are as follows: First, the components and items of infant's happiness scale selected through the literature, the previous measurement tool, and the focus group interview were 8 components and 29 items. The items were composed of 4 items of problem behavior, 4 items of achievement through immersion, 4 items of relationship with friends, 4 items of relationship with teacher, 3 items of physical environment, 4 items of positive emotion, 3 items of negative emotion, and 3 items of health. Second, as a result of validation of validity for infant's happiness scale, the item fit was confirmed with CFI=0.89, TLI=0.88, and RMR=0.05. Also, the construct validity was confirmed with convergent validity and discriminant validity. The concurrent validity was significantly correlated with the components of the previously developed measurement tools, and the reliability was appeared with 0.71-0.89. The infant's happiness scale developed in this study ensured reliability and validity as a measurement to measure infant happiness. Therefore, this scale is expected to be used as a major test tool to develope and verify a program for promoting infant happiness.

• The Journal of Korean Physical Therapy
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• v.29 no.1
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• pp.16-26
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• 2017

Purpose: This study was conducted to develop a Korean version of the trunk control measurement scale (TCMS) and examine the reliability and concurrent validity of the K-TCMS in children with cerebral palsy. Methods: Subjects for the study were 23 children with cerebral palsy (CP)(mean age: 84.70 months) recruited from one CP clinic. For the interrater and test-retest reliabilities, four raters (A, B, C, D) measured the K-TCMS two times using video clips with an interval of two weeks. For the concurrent validity, the Korean version of the gross motor function measure (K-GMFM) was chosen. Inter-rater reliability and test-retest reliability of the three K-TCMS subscale (static sitting balance, dynamic sitting balance and dynamic reaching) scores and the total scores were investigated using the intra-correlation coefficient ($ICC_{3,1}$). Spearman's correlation coefficient (r) was calculated to investigate the concurrent validity. Results: The inter-rater reliability of the K-TCMS subscales and total scores were all high ($ICC_{3,1}=0.968-0.992$). For the test-retest reliability, $ICC_{3,1}=0.827-0.962$. The concurrent validity between the K-TCMS's total and three subscale scores and K-GMFM's total score were r=0.600-0.667. Conclusion: The results suggest that the K-TCMS can be used in clinical and research settings as a standardized tool for CP children. The K-TCMS might be also useful for selecting treatment goals and planning interventions for children with cerebral palsy.

• Proceedings of the Korean Geotechical Society Conference
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• 2006.03a
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• pp.1046-1053
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• 2006

In the large scale recent reclaiming works performed within the wide spatial boundary, evaluation of long-term consolidation settlement and residual settlement of the whole construction area is sometimes made with the results of the limited ground investigation and measurement. Then the reliability of evaluation has limitations due to the spatial uncertainty. Additionally, in case of large scale deep excavation works such as urban subway construction, there are a lot of hazardous elements to threaten the safety of underground pipes or adjacent structures. Therefore it is necessary to introduce a damage prediction system of adjacent structures and others. For the more accurate analysis of monitoring information in the wide spatial boundary works and large scale urban deep excavations, it is necessary to perform statistical and spatial analysis considering the geographical spatial effect of ground and monitoring information in stead of using diagrammatization method based on a time-series data expression that is traditionally used. And also it is necessary that enormous ground information and measurement data, digital maps are accumulated in a database, and they are controlled in a integrating system. On the abovementioned point of view, we developed Geomonitor 2.0, an Internet based real time monitoring program with a new concept by adding GIS and geo-statistical analysis method to the existing real time integrated measurement system that is already developed and under useful use. The new program enables the spatial analysis and database of monitoring data and ground information, and helps the construction- related persons make a quick and accurate decision for the economical and safe construction.

• Korean Journal of Occupational Health Nursing
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• v.16 no.1
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• pp.48-57
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• 2007

Purpose: To develop the stress coping behavior measurement scale(SCBMS) for the workers in manufacturing industry. Methods: Developing of SCBMS was based on job stress and psycho-social health status. Job stress and psycho-social health status were estimated by using the Karasek's job content questionnaire (JCQ) and the general health questionnaire (GHQ-28), and the general characteristics for subjects were estimated by self-reported questionnaire and interview. Result: The subjects were 456 male workers who had never been occupationally exposed to hazardous chemical and other materials, was mean age 31.27 years and mean work duration was 4.81 years. As a result of factor analysis for developed stress coping questionnaire, four factors were extracted such as inactive, active, health and emotional behavior from 15 question items of stress coping questionnaire. Fifteen items passed for item internal consistency (100% success rate) and item discriminant validity (100% success rate). Cronbach's alpha coefficient for each factor ranged from 0.56 to 0.77. The active behavior correlated positively with job demand of JCQ (r=0.12, p<0.05), but total GHQ-28 was negatively correlation (r=-0.24, p<0.01), respectively. Conclusion: These results demonstrated the reliability and validity of SCBMS. Thus, the results may prove to be a useful assessment tool in evaluating stress coping behavior.