• Title/Summary/Keyword: Environment Tests

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A Study on Impact of Nursing Work Environment, Interpersonal Skills, and Grit on Field Adaptation of Nurses Who Have Experienced Department Transfers (부서이동을 경험한 간호사의 간호근무환경, 대인관계능력, 그릿이 현장적응에 미치는 영향)

  • Lee, Su Jeong;Lee, Yun Mi
    • Journal of Korean Critical Care Nursing
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    • v.17 no.2
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    • pp.71-82
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    • 2024
  • Purpose : This study aims to identify the factors influencing field adaptation among nurses who have undergone department transfers, by examining the levels of and the relationships between their nursing work environment, interpersonal skills, grit, and field adaptation. Methods : The study involved 137 nurses who had experienced at least one department transfer within the last three years across two hospitals. Data analysis was performed using SPSS/WIN 29.0, involving descriptive statistics, means, standard deviations, independent t-tests, one-way ANOVA, Scheffé post-hoc tests, Pearson correlation coefficients, and multiple regression analysis (enter method). Results : Factors affecting field adaptation included the nursing work environment (β=.37, p<.001), interpersonal skills (β=.19, p=.021) and grit (β=.18, p=.025), with a total explanatory power of 31% (F=12.16, p<.001). Conclusion : This study contributes insights into effective nursing personnel management, offers foundational data for managing department transfers, and aims to improve the overall quality of nursing care.

로켓엔진용 연료펌프의 성능 시험

  • Kim, Dae-Jin;Hong, Soon-Sam;Choi, Chang-Ho;Kim, Jin-Han
    • Aerospace Engineering and Technology
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    • v.4 no.1
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    • pp.143-149
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    • 2005
  • To evaluate the hydraulic and cavitation performance of a fuel pump for a liquid rocket engine, performance tests of the pump, which consist of hydraulic tests and cavitation tests, were conducted in water environment with various condition. In the hydraulic tests, the head, efficiency and volute pressure distribution of the pump are found to follow the conventional similarity rule, whereas the secondary flow pressure shows a small deviation from the similarity rule. As the floating gap is constricted, the efficiency of the pump improves and the secondary flow pressure decreases. However, the inner diameter of bypass line orifice does not show clear relationship with the pump efficiency. In the cavitation tests, measurements of the head and the NPSH indicate that the pump shows better cavitation performance as the rotational speed of the pump increases.

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Sliding Wear and Fretting Wear of Steam Generator Tube Materials (증기발생기 튜브재질의 미끄럼 마멸 및 프레팅 마멸 특성)

  • 김동구;조정우;이영제
    • Tribology and Lubricants
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    • v.17 no.5
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    • pp.380-385
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    • 2001
  • In nuclear power steam generators, high flow rates can induce vibration of the tubes resulting in fretting wear damage due to contacts between the tubes and their supports. In this paper the fretting wear tests and the sliding wear tests were performed using the steam generator tube materials of Inconel 600 and 690 against STS 304. Sliding tests with the pin-on-disk type tribometer were done under various applied loads and sliding speeds at air environment. Fretting tests were done under various vibrating amplitudes and applied normal loads. From the results of sliding and fretting wear tests, the wear of Inconel 600 and 690 can be predictable using the work rate model. Depending on normal loads and vibrating amplitudes, distinctively different wear mechanisms and often drastically different wear rates can occur. It was found the results that the wear coefficients for Inconel 600 and 690 were 262.3$\times$10$\^$-15/Pa$\^$-1/ and 209.2$\times$10$\^$-15/Pa$\^$-1/, respectively. This study shows that Inconel 690 can provide much better wear resistance than Inconel 600 in air.

A Study on the Thermal Sensation Vote of the Log House in Winter Season (통나무집의 동절기 실내 온열감 평가에 관한 연구)

  • Min, Byeong-Cheol;Jeon, Ji-Hyeon;Shin, Yong-Gyu;Kang, Sang-Woo;Kook, Chan
    • Proceeding of Spring/Autumn Annual Conference of KHA
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    • 2006.11a
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    • pp.297-300
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    • 2006
  • Various buildings constructed by environmentally friendly resources are being built in KOREA. Especially the building made by the wood, which has environmental characteristics that the reinforced concrete and brick doesn't have, are acknowledged with its superiority. Then, studies on indoor thermal control capability of the wooden building and influence of its indoor environment to sensory environment of occupants are not enough proceed. Thus, there were proceeded 24 hours measurements for indoor and outdoor thermal environmental elements of Log Cabins and the hourly subjective tests to evaluate indoor amenity of occupants in this study. The results of the study are following: 1) Upon evaluation on thermal environment elements, indoor and outdoor dry bulb temp were 22.0$^{\circ}C$ and -2.9$^{\circ}C$, and Indoor and outdoor average relative humidity were 25.8%and 52.7%. Differences of indoor and outdoor temperature and humidity were 24.9$^{\circ}C$ and 26.9%. 2) Upon contrastive analysis between the results of subjective tests, warm and cold sensation vote, and PMV (Predicted Mean Vote) and PPD (Predicted Percent Dissatisfaction), values of subjective tests W.9

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Evaluation of Local Velocity Gradient and Total Mass transfer Time at Various Rotating Velocity by Using Computational Fluid Dynamics (CFD를 이용한 패들교반속도에 따른 속도경사 및 총물질전달시간 산정)

  • Jun, Hang-Bae;Tian, Dong-Jie;Hong, Ki-Won;Han, Hong-Sig;Park, Byeong-Chang
    • Journal of Korean Society on Water Environment
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    • v.30 no.2
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    • pp.166-174
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    • 2014
  • Velocity gradient, G, a measure of the average velocity gradient in the fluid has been applied for complete mixing of chemicals in mechanical mixing devices. G values were calculated by the power input transferred to fluid in turbulent and transient range. Chemical reactions occur so fast that total mass transfer time required for even distribution of the chemicals determine the overall reaction time. The total mass transfer time is composed of the time for complete mixing through the reactor and for diffusion of the chemicals into the eddy. Complete mixing time was calculated by CFD (computer fluid dynamics) and evaluated by tracer tests in 2 liter jars at different rotating speeds. Turbulent range, Reynolds number above 10,000 in regular 2 liter jars occurred at revolution speed above 100 rpm (revolution per minute), while laminar range occurred at revolution speed below 10 rpm. A typical range of rotating speed used in jar tests for water and wastewater treatment was between 10 and 300 rpm, which covered both transient and turbulent range. G values supplied from a commercial jar test apparatus showed big difference from those calculated with power number specially in turbulent range. Diffusion time through eddy decreased 1.5 power-law of rotating speed. Complete mixing time determined by pumping number decreased increases in rotating speed. Total mass transfer time, finally, decreases as rotating speed increases, and it becomes 1 sec at rotating speed of 1,000 rpm. Complete mixing times evaluated from tracer tests showed higher than those calculated by power number at higher rotating speed. Complete mixing times, however, calculated by CFD showed similar to those of experimentally evaluated ones.

A Study to Evaluate Performance of Poly-Urethane Polymer Concrete for Long-Span Orthotropic Steel Bridge (장경간 강바닥판 케이블교량에 적용하기 위한 폴리우레탄 폴리머콘크리트의 공용특성 연구)

  • Park, Heeyoung;Lee, Junghun;Kwak, Byeongseok;Choi, Iehyun;Kim, Taewoo
    • International Journal of Highway Engineering
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    • v.15 no.1
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    • pp.1-9
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    • 2013
  • PURPOSES: The purpose of this study is to evaluate physical properties, durability, fatigue resistance, and long-term performance of poly-urethane concrete (PU) which can be possible application of thin layer on long-span orthotropic steel bridge and to check structural stability of bridge structure. METHODS : Various tests of physical properties, such as flexural strength, tensile strength, bond strength and coefficient of thermal expansion tests were conducted for physical property evaluation using two types of poly urethane concrete which have different curing time. Freezing and thawing test, accelerated weathering test and chloride ion penetration test were performed to evaluate the effect of exposed to marine environment. Beam fatigue test and small scale accelerated pavement test were performed to assess the resistance of PU against fatigue damage and long-term performance. Structural analysis were conducted to figure out structural stability of bridge structure and thin bridge deck pavement system. RESULTS: The property tests results showed that similar results were observed overall however the flexural strength of PUa was higher than those of PUb. It was also found that PU materials showed durability at marine environment. Beam fatigue test results showed that the resistances of the PUa against fatigue damage were two times higher than those of the PUb. It was found form small scale accelerated pavement test to evaluate long-term performance that there is no distress observed after 800,000 load applications. Structural analysis to figure out structural stability of bridge structure and thin bridge deck pavement system indicated that bridge structures were needed to increase thickness of steel deck plate or to improve longitudinal rib shape. CONCLUSIONS: It has been known that the use of PU can be positively considered to thin layer on long-span orthotropic steel bridge in terms of properties considered marine environment, resistance of fatigue damage and long-term performance.

Characterization of Polyurethane and Soil Layers for In-situ Treatment of Landfill Leachate (매립지 침출수 현장 처리를 위한 폴리우레탄과 개질토의 특성 분석 실험에 관한 연구)

  • Park, Chan-Soo;Jung, Young-Wook;Park, Joong sub;Back, Won seok;Shin, Won sik;Chun, Byung sik;Han, Woo-Sun;Park, Jae-Woo
    • Journal of Korean Society on Water Environment
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    • v.23 no.2
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    • pp.281-286
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    • 2007
  • A chemical and biological permeable barrier with economic feasibility is suggested to treat landfill leachate in this study. The proposed composite layers consist of bentonite, and polyurethane (PU) foam that is mixed with powdered activated carbon (PAC) and inoculated with microorganisms from local wastewater treatment plant. Each layer is mixed with local sand, and yellow brown soil. Batch tests were conducted to investigate the sorptions of nitrate on the PU foam and PAC, and nitrification/denitrification rate of each layer material. Nitrification occurred in 30 minutes with initial ammonia concentration of 100 mg/L, and the concentration of nitrate attached in the PU foam increased after 270 minutes. Results of denitrification batch tests showed 76.6%, 87.3% and 88% of nitrate removal efficiency at 10%, 20% and 30% of the volume ratio of PU foam, respectively. The pH increased from 7 to 9.42, and alkalinity increased from 980 mg/L to 1720 mg/L during the denitrification batch tests. In the column experiments using the proposed composite layers with 20% of the volume ratio of the PU foam, about 96% of BOD, 63% of COD, 58.1~79.5% of total nitrogen were removed.

Proposed Shear Load-transfer Curves for Prebored and Precast Steel Piles (강관 매입말뚝의 주면 하중전이 곡선(t-z) 제안)

  • Kim, Do-Hyun;Park, Jong-Jeon;Chang, Yong-Chai;Jeong, Sang-Seom
    • Journal of the Korean Geotechnical Society
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    • v.34 no.12
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    • pp.43-58
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    • 2018
  • In this study, the load-transfer behavior along the shaft of the prebored and precast piles was investigated by pile loading tests. Special attention was given to quantifying the skin frictions developed between the pile-soil interfaces of the 14 instrumented test piles. Based on this detailed field tests, the load - settlement curves and axial load distributions of piles were obtained and the load-transfer curves (t-z curves) for the test piles were proposed. As such, it is found that the test results show two different load transfer behaviors; ductile and brittle behavior curves. The corresponding t-z curves are proposed based on the hyperbolic- and sawtooth-shape, respectively. By validating the accuracy of the proposed curves, it is also found that the prediction results based on the proposed load-transfer curve are in good agreement with the general trends observed by the field loading tests.

LAUNCH ENVIRONMENT TEST OF KOMPSAT-1 SATELLITE

  • Lee, Sang-Seol;Kim, Hong-Bae;Moon, Sang-Mu;Woo, Sung-Hyun
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2000.06a
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    • pp.1234-1239
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    • 2000
  • KOMPSAT-1(Korea Multi-Purpose Satellite), which opened the space era in Korean peninsula, was developed from 1994 and launched successfully in December of 1999 at VAFB, USA. This paper presents a launch environment test of KOMPSAT and a short description of environment test facilities at Korea Aerospace Research Institute as well. The launch environment tests of KOMPSAT-1 satellite, such as vibration, acoustic, pyro-shock and mass properties measurement test, were performed during its system integration and test period. The participating engineers concluded that KOMPSAT-1 satellite would withstand environment during its launch period.

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The Development and Validity of the Home Literacy Environment Rating Scale (유아를 위한 가정문해환경 평정척도 개발 및 타당화 연구)

  • Park, Chan-Hwa;Kim, Gil-Sook
    • Journal of the Korean Home Economics Association
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    • v.46 no.9
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    • pp.87-97
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    • 2008
  • This study was conducted to develop the Home Literacy Environment Rating Scale(HLERS) and to analyze its item discrimination, reliability, and validity. The participants of this study were 438 parents whose children were three to five years old. The item discrimination, determined by comparing the highest and lowest group using Chi-square($x^2$) and Cramer's V, was found to be satisfactory. The Cronbach's $\alpha$ for internal consistency reliability was .78. Factor analysis revealed that the structure of the HLERS consisted of three factors: 'reading books,' 'reading behavior and modeling of parents' and 'literacy learning.' The concurrent validity was also identified by correlation between the HLERS and two sub-tests of EC-HOME. In conclusion, these results demonstrated that the Home Literacy Environment Rating Scale is reliable and valid to examine the home literacy environment for Korean families.