• Title/Summary/Keyword: 신뢰성 측정

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Development of 10 μmol/mol Hydrogen Sulfide Primary Standard Gas for Odor Measurements (악취측정용 10 μmol/mol 황화수소 표준가스 개발)

  • Kim, Yong-Doo;Bae, Hyun-Kil;Kim, Dalho;Oh, Sang-Hyub;Lee, Jin Hong;Lee, Sangil
    • Journal of the Korean Institute of Gas
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    • v.22 no.2
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    • pp.46-51
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    • 2018
  • Hydrogen sulfide from landfill and sewage treatment plant is a major odor component and causes many civil petitions. Rapidly developing industries release hydrogen sulfide, an odorous gas, to the atmosphere. This study aims to develop a $10{\mu}mol/mol$ concentration level hydrogen sulfide primary standard gas for odor measurement. The hydrogen sulfide gas was prepared at a nominal concentration of $10{\mu}mol/mol$ in nitrogen using the gravimetric method described in ISO 6142. Replicate standard gases were produced in 4 aluminium cylinders, and their concentrations were verified by GC-AED. The uncertainty of production was less than 0.50 %, and the variation of the 4 replicates was 0.22 %. The wall adsorption of hydrogen sulfide in cylinders was 0.10 % at 1500 psi, and the concentration was estimated to be long-term stable for one year. The relative expanded uncertainty of the preparation consistency, adsorption and long-term stability of this hydrogen sulfide standard gas was less than 1.05 % (95 % of confidence level, k=2).

Structural Relationship between Leadership Type of Hospital Organization and Organizational Commitment and Job Performance (병원 조직의 리더십유형과 조직몰입, 직무성과의 구조적인 관계)

  • Lee, Jin?Woo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.6
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    • pp.290-301
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    • 2017
  • This study examined the causal relationship among the leadership type, organizational commitment, and job performance, and to improve the organizational performance and effective methods of human resource management in hospital organizations. The survey period was from October 6, 2016 to October 20, and 375 employees working in hospitals were selected for the final survey. To analyze the validity of the measurement variables, reliability and confirmatory factor analysis were conducted, and the covariance structure equation analysis was conducted to grasp the causal relationship among leadership, organizational commitment, and job performance. In conclusion, leadership, organizational commitment, and job performance were significantly different according to the occupation(p<0.05), age(p<0.05), and working period(p<0.05), and individual care(p<0.001) and conditional reward(p<0.001) showed a high causal relationship with the organizational commitment and job performance. In the future, leadership that can take care of the individual characteristics of the members of the organization and ability to demonstrate their competence will be needed, and it will be necessary to establish a reasonable compensation system after measuring the degree of achievement of work. In addition, leadership needs to be in place to promote organizational performance considering the job type, gender, age, and duration of work. Managers should make efforts to form an organizational culture and provide related education programs to improve loyalty and attachment of members to the organization.

Failure Analysis by Fracture Study of Connecting Rod Bolts in Diesel Engine for Military Tracked Vehicles (군용 궤도차량 디젤엔진의 커넥팅 로드 볼트 파손 검토를 통한 고장원인분석)

  • Oh, Dae San;Kim, Ji Hoon;Seo, Suk Ho
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.7
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    • pp.191-200
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    • 2020
  • Tracked military vehicles are operated under harsher conditions and climates than ordinary vehicles, and the components require high degrees of reliability and durability. A diesel engine is the main power generator, and when the vehicle breaks down, there is a high possibility of causing a large-scale accident. Therefore, analyzing the cause of engine failure can be important for preventing similar cases that may occur. In this study, we clarified the mechanism of engine failure according to an overhaul test, hardness measurement, and an analysis of the fracture surface. The overhaul test confirmed that a bolt was separated from the connecting rod (number 4). In addition, the hardness measurement results of the connecting rod bolt conformed to the standard, and it was found that the bolt fracture was ductile fracture through an analysis of the fracture surface. Based on the results, it was concluded that damage to a diesel engine of a tracked military vehicle was caused by separating and damage caused by loosening of the connecting rod bolts, resulting in cascading damage. The results of the study could be used as reference examples and could be useful for another study on engine failure analysis.

Alternative hitting ability index for KBO (한국프로야구에서 타자력 지수 제안)

  • Hong, Chong Sun;Kim, Jae Young;Shin, Dong Sik
    • Journal of the Korean Data and Information Science Society
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    • v.27 no.3
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    • pp.677-687
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    • 2016
  • Among lots of sabermetric statistics for baseball batters' ability, the wins above replacement (WAR) is the most popular statistic in MLB. However, there exists a difficulty applying WAR to KBO, since KBO data do not have position adjustment, league adjustment and park factor which are essential in calculating WAR. In this paper, using five statistics for both KBO and MLB qualified batters, we propose hitting ability index (HAI), an alternative sabermetric indices to represent batters' ability. Comparing HAI with WAR of MLB batters, we evaluate the validity of HAI and then applied HAI to 2015 KBO data in which HAI is analyzed statistically with respect to different teams, ages, and positions. Moreover, the linear relationship between KBO batter's HAI and their annual salary is discussed. Grouping 46 KBO batters based on confidence region of the regression model for annual salary, we also statistically investigate batter's annual salary in these groups with respect to several factors.

Effects of Sm:Ba:Cu Composition Ratio on the Superconducting Properties of SmBCO Coated Conductor Prepared by using a Composition Gradient Method (SmBCO 초전도 선재 특성에 대한 Sm:Ba:Cu 조성비의 영향)

  • Kim, H.S.;Oh, S.S.;Jang, S.H.;Min, C.H.;Ha, H.S.;Ha, D.W.;Ko, R.K.;Youm, D.J.;Moon, S.H.;Chung, K.C.
    • Progress in Superconductivity
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    • v.13 no.1
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    • pp.7-11
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    • 2011
  • The effects of Sm:Ba:Cu composition ratio in SmBCO coated conductor on their superconducting properties were investigated. The SmBCO coated conductors were fabricated by reactive co-evaporation method using EDDC(Evaporation using Drum in Dual Chamber) system. In this system, we could obtain various samples with different composition ratios in a batch by the technique providing composition gradient at deposition zone. From the specimens prepared by EDDC system, we found that composition ratio is uniform parallel to the drum axis, but gradient along the circumferential direction of the drum. We installed a shield having parallelogram open area between the deposition chamber and the evaporation chamber in EDDC system, and attached a 30 cm long template, which is parallel to drum axis, onto the drum surface. In this configuration, we could obtain SmBCO coated conductors having a gradient composition along the length of template. We measured the composition ratios and surface morphologies with periodic interval by SEM and EDAX, and confirmed the profile of composition ratio. We also measured critical current using non-contact Hall probe critical current measurement system and thereby could plot composition ratio vs. critical current. The maximum critical current was obtained, and the surface morphology with the shape of roof tile was observed at the corresponding composition ratio of Sm:Ba:Cu = 1.01:1.99:4.87. It was also found that composition ratio had an effect on not only critical current but also surface morphology.

Evaluation and Comparison of Contrast to Noise Ratio and Signal to Noise Ratio According to Change of Reconstruction on Breast PET/CT (Breast PET CT 영상 재구성 변화에 따른 대조도 대 잡음비와 신호 대 잡음비의 비교평가)

  • Lee, Jea-Young;Lee, Eul-Kyu;Kim, Ki-Won;Jeong, Hoi-Woun;Lyu, Kwang-Yeul;Park, Hoon-Hee;Son, Jin-Hyun;Min, Jung-Whan
    • Journal of radiological science and technology
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    • v.40 no.1
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    • pp.79-85
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    • 2017
  • The purpose of this study was to measure contrast to noise ratio (CNR) and signal to noise ratio (SNR) according to change of reconstruction from region of interest (ROI) in breast positron emission tomography-computed tomography (PET-CT), and to analyze the CNR and SNR statically. We examined images of breast PET-CT of 100 patients in a University-affiliated hospital, Seoul, Korea. Each patient's image of breast PET-CT were calculated by using ImageJ. Differences of CNR and SNR among four reconstruction algorithms were tested by SPSS Statistics21 ANOVA test for there was statistical significance (p<0.05). We have analysis socio-demographical variables, CNR and SNR according to reconstruction images, 95% confidence according to CNR and SNR of reconstruction and difference in a mean of CNR and SNR. SNR results, with the quality of distributions in the order of PSF_TOF, Iterative and Iterative-TOF, FBP-TOF. CNR, with the quality of distributions in the order of PSF_TOF, Iterative and Iterative-TOF, FBP-TOF. CNR and SNR of PET-CT reconstruction methods of the breast would be useful to evaluate breast diseases.

A Study on the Effects of Mindset on the Cabin Crew's Stress and Job Performance (마인드셋이 객실승무원의 스트레스, 직무성과에 미치는 영향에 관한 연구)

  • Kim, Ha-Young
    • Journal of Convergence for Information Technology
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    • v.10 no.11
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    • pp.156-167
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    • 2020
  • The purpose of this study is to analyze the influence of the mindset on stress and job performance. For the analysis, a questionnaire is conducted for cabin crew members in K airlines, and a total of 266 copies are used for the final analysis. To verify the hypotheses of the study, frequency analysis, exploratory factor analysis, reliability analysis, confirmatory factor analysis, measurement model analysis, validation of the measuremen model, and structural equation model analysis are used based on the questionnaire. First, it is confirmed that the mindset had a negative (-) effect on the cabin crew's role stress, reward stress and relationship stress. Second, it is found that cabin crew's reward stress have a negative (-) effect on job performance. On the other hand, relationship stress is found to have a positive influence on job performance and there is no significant result in effect with role stress. Third, the mindset showes a significant positive impact relationship on job performance. As a result, it is necessary to introduce a mindset intervention program so that it can be applied in practical work. These research results confirm the positive effects of mindsets and show that they contribute to organizational performance. In addition, it is necessary to prepare a program to change the mindset of airline cabin crew and to be applied in actual work.

Test-retest Reliability and Intratest Repeatability of Measuring Lumbar Range of Motion Using Inertial Measurement Unit (관성측정장치를 이용한 요추 가동범위 측정방법의 반복성 및 검사자 내 검사-재검사 신뢰도 연구)

  • Ahn, Ji Hoon;Kim, Hyun Ho;Youn, Woo Suck;Lee, Sun Ho;Shin, You Bin;Kim, Sang Min;Park, Young Jae;Park, Young Bae
    • Journal of Acupuncture Research
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    • v.31 no.1
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    • pp.61-73
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    • 2014
  • Objectives : The purpose of this study is to estimate the test-retest reliability and the intratest repeatability in measuring the lumbar range of motion of healthy volunteers with wireless microelectromechanical system inertial measurement unit(MEMS-IMU) system and to discuss the feasibility of this system in the clinical setting to evaluate the lumbar spine movement. Methods : 19 healthy male volunteers were participated, who got under 21 points at oswestry disability index(ODI) were adopted. Their lumbar motion were measured with IMU twice in consecutive an hour for the test-retest reliability study. Intratest repeatability was calculated in the two tests separately. The calculated intraclass correlation coefficients(ICC) were discussed and compared with the those of the previous studies. Results : Lumbar range of motion of flexion $41.45^{\circ}$, extension $16.34^{\circ}$, right lateral bending $16.41^{\circ}$ left lateral bending $13.63^{\circ}$ right rotation $-2.47^{\circ}$, left rotation $-0.61^{\circ}$. ICCs were 0.96~1.00(intratest repeatability) and 0.61~0.92(test-retest reliability). Conclusion : This study shows that MEMS-IMU system demonstrates a high test-retest reliability and intratest repeatability by calculated intraclass correlation coefficients. The results of this study represents that wireless inertial sensor measurement system has portable and economical efficiency. By MEMS-IMU system, we can measures lumbar range of motion and analyze lumbar motion effectively.

Test-retest Reliability and Intratest Repeatability of Measuring Cervical Range of Motion Using Inertial Measurement Unit (관성측정장치를 이용한 경추관절 가동범위 측정의 검사 내 반복성 및 검사-재검사 신뢰도 연구)

  • Kim, Hyun Ho;Kim, Kyung Wook;Park, Ji Min;Kim, Eun Seok;Lee, Min Jun;Kang, Jung Won;Lee, Sang Hoon;Park, Young Bae
    • Journal of Acupuncture Research
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    • v.30 no.4
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    • pp.25-33
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    • 2013
  • Objectives : To assess the test-retest reliability and the intratest repeatability in measuring the cervical range of motion of healthy subjects with wireless microelectromechanical system inertial measurement unit(MEMS-IMU) system and to discuss the feasibility of this system in the clinical setting to evaluate the cervical spine musculoskeletal. Methods : 12 healthy people who were evaluated as no- or mild-disability with neck disability index were participated. Their cervical motion were measured with IMU twice in consecutive two days for the test-retest reliability study. Intratest repeatability was calculated in the two tests separately. The calculated intraclass correlation coefficients(ICC) were discussed and compared with the those of the previous studies. Results : Cervical range of motion data were acquired and statistically processed: left rotation($61.64^{\circ}$), right rotation($65.12^{\circ}$), extension($61.98^{\circ}$), flexion($52.81^{\circ}$), left bending($39.31^{\circ}$), right bending($41.08^{\circ}$). ICCs were 0.77~0.98(intratest repeatability) and 0.74~0.93 (test-retest reliability) in the primary motion. In the coupling motion, intratest repeatability ICCs were 0.93~ 0.99(transverse primary plane), 0.88~0.97(saggital primay plane), and 0.77~0.93(coronal primary plane). Test-retest reliability of coupling motion were 0.90~0.97(transverse primary plane), 0.00~0.72(saggital primary plane), and 0.04~0.76(coronal primary plane). Conclusions : Several types of range-of-motion devices are now on use in many fields including medicine, but the practicality of the devices in clinical use is questionable for the convenient and economical aspects. In this study, we presented the reliability of cervical range of motion test with the developed wireless MEMS-IMU system and discussed its potential utility in clinical use.

Validation of the Korean Version of the Perfectionism Inventory (PI) for Gifted Students (한국판 PI(Perfectionism Inventory)의 타당화 연구: 영재학생을 대상으로)

  • Yoon, So-Young;Han, Ki-Soon
    • Journal of Gifted/Talented Education
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    • v.25 no.5
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    • pp.749-765
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    • 2015
  • This study is aimed at validation of the Korean Version of the Perfectionism Inventory which was developed by Hill et al.(2004). To do so, exploratory factor analysis and confirmatory factor analysis with 167 science high school and 161 middle school gifted students were conducted. It appeared 6 factor structure consisting of 'Self-Evaluative Perfection Strivings', 'Parental Pressure', 'Planfulness', 'Striving for Excellence', 'High Standards for Others', and 'Organization', which does not support 8 factor of the original scale. As a result, Cronbach's ${\alpha}$ ranged from .78 to .92 for subscale of PI and .93 for the total scale. The fit of measurement model was found to be ${\chi}^2=1257.618$ (df=792, p=.00), TLI=.903, CFI=.911, RMSEA=.047, indicating most of fit indexes were acceptable. Also, the validity of the scale was examined by the correlations between the PI and MPS. PI Korean version is significant to confirm the factor structure and validity of perfectionism which was influenced by characteristics of gifted students and Korean culture. These results show that the PI is quite reliable and valid tool for measuring perfectionism for gifted students.