• Title/Summary/Keyword: burn-out

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The research on changes in turnover intention due to the degree of occupational stress and the mediating parameters in fire-officerse Mice

  • kang, Kwang Soon;Ji, Dong Ha
    • Journal of the Korea Society of Computer and Information
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    • v.22 no.7
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    • pp.109-115
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    • 2017
  • This study was performed to investigate the changes in turnover intention according to the level of occupational stress and to find the mediating factor that reducing the turnover intention among fire officer. To compare change of turnover intention according to the degree of occupational stress, statistical analyses were done by using the logistic regression model. In logistic regression analysis, the possibility of high turnover intention in a group with high occupational stress was hjgher by 4.11 times than a group with low occupational stress. The results of analyzing the degree of change in turnover intention after applying the mediating parameters(physical condition, emotional labor, burn out), turnover intention decreased by about 50.6%(from 4.11 times to 2.03 times) at the high level of occupational stress. As a result, it was found that the occupational stress experienced by the fire-officers had a positive effect on the turnover intention. In order to reduce the turnover intention due to the occupational stress of the fire-officers, it is necessary to manage factors such as work environmental factors(emotional labor, burn out) and individual factor(physical condition).

A Study on Boiling Heat Transfer in a Impinging Subcooled Water Jet System (충돌과냉수분류(衝突過冷水噴流)의 비등열전달(沸騰熱傳達)에 관한 연구(硏究))

  • Lee, G.J.;Lee, J.S.;Ohm, K.C.;Cho, Y.C.;Seo, J.Y.
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.5 no.1
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    • pp.10-17
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    • 1993
  • This paper describes the boiling heat transfer phenomena to be divided into three regions, nonboiling, nucleate boiling and burn-out in the impinging subcooled water jet system. In the nonboiling region, Nusselt number is a function of Prandtl number, Reynolds number and ${\Delta}T_{sub}/T_{ast}$ In the nucleate boiling region, the heat flux increases with increment of the nozzle exit velocity. But the degree of liquid subcooling does not affect the shape of the nucleate boilng curve. The dimensionless correlations can be expressed in the form of $q{\ell}/K_f{\Delta}T_{ast}=C(Bo{\cdot}C_p{\cdot}{\Delta}T_{sat}/Vo^2)^m{\cdot}(Re/We)^n$. The burn-out heat flux increases linearly with increment of the nozzle exit velocity, but independs of degree of subcooling and the supplementary water height.

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Properties of Low Temperature Cofired Ceramics Sheets with Binder Content and Laminated Pressure (바인더 함량 및 적층압력 변화에 따른 LTCC 시트 특성)

  • You, Jung-Hun;Yeo, Dong-Hun;Lee, Joo-Sung;Nam, Joong-Hee;Wang, Jong-Hoe;Yoon, Ho-Gyu
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2006.06a
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    • pp.278-279
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    • 2006
  • 저온동시소성 다층세라믹스 시트 제조시 바인더 함량과 압력 변화에 따른 적층체의 그린밀도, 적층밀도, 바인더 burn out 후 그린밀도, 소결밀도를 고찰하였다. 바인더 함량이 증가함에 따라 slurrly의 유변학적 변화는 그린시트의 유동성 및 충진율을 변화시켜 그린시트의 밀도에 영향을 주었다. 적층 압력을 5~50MPa로 변화시켰을 때 바인더 함량이 12%로 가장 많은 시트의 경우 적층 후 시트의 밀도는 상대적으로 높은 밀도값을 나타내었으나, 바인더 burn out 후에는 상대적으로 낮은 밀도값을 나타내었다. 바인더 함량 변화에 따른 소결 밀도값은 큰 차이를 보이지 않았다.

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Study for Transient Voltage Characteristic by Power Switching on Aircraft Electrical Master Box (항공기용 전원분배장치의 전원개폐에 의한 과도전압 특성 연구)

  • Seo, Youngjin;Ji, Sangyong;Jo, Jihyung
    • Journal of Aerospace System Engineering
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    • v.13 no.5
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    • pp.24-31
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    • 2019
  • In this study, we analyzed the cause of the burn out phenomenon in the power distribution system for aircraft and proposed the improvement method. The power distribution device for aircraft has an AC and DC, and there is a rectifier between the two devices. The capacitors in the power board burn out when the power is turned on and off. The main reason for this is the excessive voltage caused by the inductance built into the rectifier. The cases that can cause a failure are classified. The impact was analyzed and the solution was established through the experimental method.

Effect of Professional Quality of Life on the Professional Self-Concept of Intensive Care Unit Nurses in Tertiary Hospital (상급종합병원 중환자실 간호사의 전문직 삶의 질이 전문직 자아개념에 미치는 영향)

  • Hong, Jin Young;Sohn, Sue Kyung
    • Journal of Korean Critical Care Nursing
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    • v.12 no.2
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    • pp.13-25
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    • 2019
  • Purpose : The purpose of this study was to identify factors influencing the professional self-concept of nurses working in intensive care units (ICUs). Methods : Data were collected from July 1 to August 15, 2014. The subjects were 206 ICU nurses working in four university hospitals in B and U cities, Korea. Their professional self-concept was measured using Arthur's Scale revised by Yoon (2012), and professional quality of life (QOL) was measured using Pro QOL Korean Ver. 5 developed by Stamm (2010). Data were analyzed with SPSS Ver. 18, using a t-test, ANOVA, Pearson's correlation coefficient, and multiple regression analysis. Results : Professional self-concept was significantly correlated with compassion satisfaction (r=.61, p<.001), and burn out (r=-.57, p<.001). The factors influencing professional self-concept were compassion satisfaction (${\beta}=.46$, p<.001), burn out (${\beta}=-.27$, p<.001), and education level (${\beta}=.14$, p =.014). The explanatory power of this model was 46.5%. Conclusion : The results suggest that the influencing factors found in this study should be considered when planning nursing intervention programs for improving the professional self-concept of ICU nurses.

Effects of Resilience on Academic Burnout of University students Majoring in Public Health: for group with Low Resilience (보건학 전공 대학생의 회복탄력성이 학업소진에 미치는 영향: 회복탄력성이 낮은 군 대상)

  • Lee, Hyun-Ju
    • The Journal of Korean Society for School & Community Health Education
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    • v.20 no.1
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    • pp.85-95
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    • 2019
  • Objectives: This study is to examine the influences of three sub-factors of resilience on academic burn out among a group of university students, with low resilience, majored in public health. Methods: The survey was made during January 1 to 13, 2017 and after checking the resilience scores of 166 respondents and the questionnaires of 115 respondents, whose scores were less than 195, an average score of Korea, were selected and analyzed using AMOS. Results: The average resilience and academic burn-out scores were 173 and 2.96, respectively. The goodness-of-fit of proposed model showed RMSEA=0.068, GFI=0.916, NFI=0.901, IFI=0.963, CFI=0.962 so, final measurement model was selected. The analysis of the suggested model showed that among three sub-factors of resilience, only self-control ability had a negative(-) effect on academic burnout and two others were shown to have no effects. Conclusion: By researching and introducing a education method that could enhance self-control ability, it would effectively reduce academic burnout in university students with low resilience and majored in public health.

An Analysis on the Deep Geological Disposal Concepts Considering the Spent Fuel Length (사용후핵연료 길이에 따른 심지층 처분시스템 분석)

  • LEE, Jongyoul;KIM, Hyeona;LEE, Minsoo;CHOI, Heuijoo;KIM, Keonyoung
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.13 no.3
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    • pp.201-209
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    • 2015
  • Currently, 23 nuclear power plants are in operation at Kori, Uljin, Younggwang and Wolsong site and a reference deep geological disposal system has been developed for the spent fuels generated by them. The reference spent fuel for this disposal system has 4.5wt% of initial enrichment, 55 GWd/MtU of burn-up, and 40 years of cooling time. In this paper, to improve disposal efficiency and economic feasibility, the characteristics of spent fuels from nuclear power plants, such as type and burn-up, were reviewed. A disposal canister concept for shorter length and relatively lower burn-up spent fuels than the reference spent fuels was developed. Based on this canister concept, thermal analyses were carried out and a deep geological disposal concept was proposed. Measures of disposal efficiency such as unit disposal area and disposal density were compared between this disposal system and the reference disposal system. Also, economic feasibility, such as the volume reduction of copper, cast iron, and bentonite, was analyzed and the results of these analyses showed that the disposal system proposed in this paper has an efficiency of at least 20%. These results could be used for establishing spent fuel management policy and designing practical disposal systems for spent fuels.

Dynamical Study on the Blasting with One-Free-Face to Utilize AN-FO Explosives (초유폭약류(硝油爆藥類)를 활용(活用)한 단일자유면발파(單一自由面發破)의 역학적(力學的) 연구(硏究))

  • Huh, Ginn
    • Economic and Environmental Geology
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    • v.5 no.4
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    • pp.187-209
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    • 1972
  • Drilling position is one of the most important factors affecting on the blasting effects. There has been many reports on several blasting factors of burn-cut by Messrs. Brown and Cook, but in this study the author tried to compare drilling positions of burn-cut to pyramid-cut, and also to correlate burn-cut effects of drilling patterns, not being dealt by Prof. Ito in his theory, which emphasized on dynamical stress analysis between explosion and free face. According to former theories, there break out additional tensile stress reflected at the free face supplemented to primary compressive stress on the blasting with one-free-face. But with these experimented new drilling patterns of burn-cut, more free faces and nearer distance of each drilling holes make blasting effects greater than any other methods. To promote the above explosive effect rationary, it has to be considered two important categories under-mentioned. First, unloaded hole in the key holes should be drilled in wider diameter possibly so that it breaks out greater stress relief. Second, key holes possibly should have closer distances each other to result clean blasting. These two important factors derived from experiments with, theories of that the larger the dia of the unloaded hole, it can be allowed wider secondary free faces and closes distances of each holes make more developed stress relief, between loaded and unloaded holes. It was suggested that most ideal distance between holes is about 4 clearance in U. S. A., but the author, according to the experiments, it results that the less distance allow, the more effective blasting with increased broken rock volume and longer drifted length can be accomplished. Developed large hole burn-cut method aimed to increase drifting length technically under the above considerations, and progressive success resulted to achieve maximum 7 blasting cycles per day with 3.1m drifting length per cycle. This achievement originated high-speed-drifting works, and it was also proven that application of Metallic AN-FO on large hole burn-cut method overcomes resistance of one-free-face. AN-FO which was favored with low price and safety handling is the mixture of the fertilizer or industrial Ammonium-Nitrate and fuel oil, and it is also experienced that it shows insensible property before the initiation, but once it is initiated by the booster, it has equal explosive power of Ammonium Nitrate Explosives (ANE). There was many reports about AN-FO. On AN-FO mixing ratio, according to these experiments, prowdered AN-FO, 93.5 : 6.5 and prilled AN-FO 94 : 6, are the best ratios. Detonation, shock, and friction sensities are all more insensitive than any other explosives. Residual gas is not toxic, too. On initation and propagation of the detonation test, prilled AN-FO is more effective than powered AN-FO. AN-FO has the best explosion power at 7 days elapsed after it has mixed. While AN-FO was used at open pit in past years prior to other conditions, the author developed new improved explosives, Metallic AN-FO and Underwater explosive, based on the experiments of these fundmental characteristics by study on its usage utilizing AN-FO. Metallic AN-FO is the mixture of AN-FO and Al, Fe-Si powder, and Underwater explosive is made from usual explosive and AN-FO. The explanations about them are described in the other paper. In this study, it is confirmed that the blasting effects of utilizing AN-FO explosives are very good.

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Effects of Firing Ambient on Rear Metallization for Silicon Solar Cells (분위기에 따른 실리콘 태양전지 후면 전극 및 후면 전계의 형상과 특성 분석)

  • Park, Sungeun;Kim, Young Do;Park, Hyomin;Kang, Yoonmook;Lee, Hae-Seok;Kim, Donghwan
    • Korean Journal of Materials Research
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    • v.25 no.7
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    • pp.336-340
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    • 2015
  • For rear metallization with Al paste, Al back contacts require good passivation, high reflectance, and a processing temperature window compatible with the front metal. In this paper, the effect of the firing ambient during the metallization process on the formation of Al rear metal was investigated. We chose three different gases as ambient gases during the firing process. Using SEM, we observed the formation of a back surface field in $N_2$, $O_2$, and Air ambients. To determine the effect of the ambient on Voc, the suns-Voc tool was used. In this study, we described the mechanism of burn-out of organic materials in Al paste during the firing process. The oxygen ambient plays an important role in the burn-out process. We calculated the efficiency with obtained the back surface recombination velocities using PC1D simulation. It was found that the presence of oxygen during the firing process influenced the uniform back surface field because the organic materials in the Al paste were efficiently burned out during heating. The optimized temperature with oxygen flow shows an absolute efficiency of 19.1% at PC1D simulation.

The Effect of Multi-ignition Strategy on the Combustion and Emission Characteristics in a Ultra Lean Burn GDI Engine (초희박 GDI엔진에서 다단점화에 의한 연소 및 배기 특성)

  • Park, Cheol-Woong;Kim, Sung-Dae;Kim, Hong-Suk;Oh, Hee-Chang;Bae, Choong-Sik
    • Transactions of the Korean Society of Automotive Engineers
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    • v.20 no.3
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    • pp.106-112
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    • 2012
  • Since air pollution problem by emissions from automotive vehicles has become social issues, lean-burn gasoline direct injection (GDI) engine is focused as an alternative to meet the requirement of reinforced emission regulation and improved fuel consumption. Spray-guided type DI combustion is promising technology, which characterized by the centrally mounted injector and closely positioned spark plug, since stable lean combustion can be realized even at ultra-lean mixture condition. In the present study, the effect of multi-ignition with developed charge coil on combustion and emission characteristics was investigated in optical accessible single cylinder engine. In order to fully understand the in-cylinder phenomena and the mechanisms of emission production, optical diagnostics, such as flame visualization was also carried out at frequently using operating condition. Multi-ignition is effective to improve fuel economy but increase NOx emission at flammability limit.