• Transactions of the Korean Society of Mechanical Engineers B
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• v.36 no.1
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• pp.61-66
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• 2012

In this study, to find the effect of nonequilibrium condensation on the oscillation of the terminating shock wave in transonic flows, an NACA0014 airfoil flow with nonequilibrium condensation is analyzed using the total variation diminishing (TVD) numerical scheme. Transonic free stream Mach numbers of 0.81-0.87 are tested with variations in the stagnation relative humidity. For the same free stream Mach number and attack angle of ${\alpha}=0^{\circ}$, an increase in the stagnation relative humidity attenuates the strength of the terminating shock and reduces the oscillation of the terminating shock wave. Furthermore, for the same stagnation relative humidity, the larger the free stream Mach number becomes, the shorter the period of the oscillation shock wave is. The excursion distance of the oscillation shock increases with the free stream Mach numbers for the same stagnation relative humidity. Finally, it is found that for the same shock location, the strength of the oscillating shock facing upstream is stronger than that facing downstream.

• Journal of Digital Convergence
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• v.16 no.2
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• pp.215-224
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• 2018

The Purpose of this study was to examine the relations between nurse image, self-esteem, major satisfaction and career identify of nursing students perceive. The participants of 410 subjects, data was analyzed using t-test, ANOVA, multiple linear regression with the SPSS/WIN 20.0 program. The results: The mean score of nurse image(3.82), self-esteem(2.64), major satisfaction(3.76), career identity(2.64) were abve the average. Nurse image, self-esteem, major satisfaction and career identity showed a positive correlation. The results of multiple linear regression analysis showed that the variables of self - esteem, major satisfaction, and career identity had an explanatory power(Adj R2=33.2% )on image of nurses. Study results suggested that, we propose a program for establishing a positive nurse image to improve the self - esteem, major satisfaction and career identity of nursing students.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.38 no.3
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• pp.219-225
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• 2014

In this study, to find the characteristics of the oscillation of a terminating shock wave in a transonic airfoil flow with non-equilibrium condensation, a NACA00-12,14,15 airfoil flow with non-equilibrium condensation is investigated through numerical analysis of TVD scheme. Transonic free stream Mach number of 0.81-0.90 with the variation of stagnation relative humidity and airfoil thickness is tested. For the free stream Mach number 0.87 and attack angle of ${\alpha}=0^{\circ}$, the increase in stagnation relative humidity attenuates the strength of the terminating shock wave and inactivates the oscillation of the terminating shock wave. For the case of $M_{\infty}=0.87$ and ${\phi}_0=60%$, the decreasing rate in the frequency of the shock oscillation caused by non-equilibrium condensation to that of ${\phi}_0=30%$ amounts to 5%. Also, as the stagnation relative humidity gets larger, the maximum coefficient of drag and the difference between the maximum and minimum in $C_D$ become smaller. On the other hand, as the thickness of the airfoil gets larger, the supersonic bubble size becomes bigger and the oscillation of the shock wave becomes higher.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.38 no.12
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• pp.1009-1015
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• 2014

The present study investigated the effects of non-equilibrium condensation with the angle of attack on the coefficients of pressure, lift, and drag in the transonic 2-D flow of NACA0012 by numerical analysis of the total variation diminishing (TVD) scheme. At $T_0=298k$ and ${\alpha}=3^{\circ}$, the lift coefficients for $M_{\infty}=0.78$ and 0.81 decreased monotonically with increasing ${\Phi}_0$. In contrast, for $M_{\infty}$ corresponding to the Mach number of the force break, $C_L$ increased with ${\Phi}_0$. For ${\alpha}=3^{\circ}$ and ${\Phi}_0=0%$, $C_D$ increased markedly as $M_{\infty}$ increased. However, at ${\Phi}_0=60%$ and ${\alpha}=3^{\circ}$, which corresponded to the case of the condensation having a large influence, $C_D$ increased slightly as $M_{\infty}$ increased. The decrease in profile drag by non-equilibrium condensation grew as the angle of attack and stagnation relative humidity increased for the same free stream transonic Mach number. At ${\Phi}_0=0%$, the coefficient of the wave drag increased with the attack angle and free stream Mach number. When ${\Phi}_0$ > 50%, the coefficient of the wave drag decreased as ${\alpha}$ and $M_{\infty}$ increased. Lowering ${\Phi}_0$ and increasing $M_{\infty}$ increased the maximum Mach number.

• Journal of Convergence for Information Technology
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• v.10 no.9
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• pp.102-110
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• 2020

The purposes of this study was to identify relationship among self-efficacy, incivility, career identity and professionalism in nursing students. The subjects were 320 junior and senior nursing students from four colleges in Gyeonggi-do. As a result of the study, the average self-efficacy was 3.90 points, incivility was 2.36 points, career identity was 2.64 points, and nursing professionalism was 3.63points. Professionalism of nursing students was positively correlated self-efficacy, career identity, but nursing professionalism was negatively correlated incivility. The predictors on nursing professionalism were self-efficacy, incivility, career identity and rudeness. These variables have explanatory power of 16.3% on nursing professionalism. Therefore, specific strategies are needed to reduce the rudeness experienced in clinical practice and change in the curriculum to increase the career identity of nursing students.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2011.04a
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• pp.453-456
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• 2011

An experimental investigation of the heat transfer characteristics of stretched premixed flames using Synthetic gas has been performed. Hydrogen and carbon mon-oxide which could be extracted from coal gasification process are the main fuel of synthetic-gas. Heat flux at the stagnation point was increased as global strainrate was increased, then the heat flux was decreased when a global strainrate reached a sudden point. Heat flux at the stagnation point is also affected by nozzle to impingement distance. Heat flux was increased as nozzle to impingement place distance was increased. This study is a foundation study of practical use of secondary gases from coals.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.05a
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• pp.901-904
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• 2002

The cutting thickness of ultra-precision machining is generally very small, only a few micrometer or even down to the order of a flew manometer. In such case, a basic understanding of the mechanism on the micro-machining process is necessary to produce a high quality surface. When machining at very small depths of cut, metal flow near a rounded tool edge become important. In this paper a finite element analysis is presented to calculate the stagnation point on the tool edge or critical depth of cut below which no cutting occurs. From the simulation, the effects of the cutting speed on the critical depths of cut were calculated and discussed. Also the transition of the stagnation point according to the increase of the depths of cut was observed.

• Korea journal of population studies
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• v.22 no.1
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• pp.93-121
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• 1999

이 연구는 인천의 정체성을 알아보는 데 연구의 초점을 맞추었다. 연구방법으로는 실증적 방법과 민속학적 방법 두 가지를 병행하였다. 시민단체, 공무원, 학생을 대상으로 임의목적표본방법을 사용하여 총 613명이 분석되었다. 분석방법은 교차통계분석 및 다중분류분석을 하였다. 정체성은 한 지역에 거주하는 주민들의 집단결속력과 성취도를 결정하여 주며, 그 지역의 사회적 통합과도 밀접한 관련을 지니고 있어서, 지역의 문제나 관심사를 해결하고 발전시키는데 가장 핵심적인 요소이다. 인천의 정체의식은 세 집단 모두 낮으며, 전체응답자의 절반 이상은 그저 그렇다는 중용의 의견이었다. 인천에 대한 정체의식을 응답집단의 특성별로 보면 여자보다는 남자가 높고, 기혼자보다는 미혼자가 높으며, 30세 이상으로 연령이 많을수록, 수입과 생활수준이 낮을수록 정체의식이 상대적으로 높게 나타났다. 그리고 전문.관리.사무직보다는 판매.서비스.생산.농업직 종사자들의 정체의식이 높았다. 전문대 정도의 교육을 받은 시민의 정체의식이 상대적으로 높고, 인천의 문화.복지.환경개선을 위한 특별기금 기부의사가 있는 시민과 인천을 마음붙이고 살 곳으로 생각하는 시민의 정체의식이 높다. 총괄적인 의미에서 본 인천의 정체성에 관한 조사를 보면, 인천은 "주인의식 없음"과 "이제부터 만들어 가야 한다"는 답변이 제일 많았고 그 다음은 "포용력", "선구적 개척정신", "긍정적인 의미의 짠물", "합중시(合衆市)적 다양성", "외세에 대한 호국정신", "세계의 관문도시"로 나타났다. 이와 같은 응답유형으로 보아서는 인천지역에 대한 이미지를 한마디로 딱 잘라 말하기는 어렵다. 그러나 인천은 서울.경기인, 충청인, 호남인, 영남인, 이북인, 외국인 등을 가리지 않고 받아드리는 "포용력이 있는 합중시적 다양성을 가진 도시"로 지역차가 서로 다른 출신성분이 공존할 수 있다는 점에서 의미하는 바가 크다. 이는 "세계속의 도시"와 "동북아의 거점도시"를 추구하는 미래지향적인 시각에서는 지역주의를 지양하고 지역통합이슈와 세계화 물결속에서 외국인에게도 열린 상태문화를 제공하는 관문이 될 것이라는 면에서 인천이 추구해야 할 정체성으로 시사하는 점이라고 본다.는 미래지향적인 시각에서는 지역주의를 지양하고 지역통합이슈와 세계화 물결속에서 외국인에게도 열린 상태문화를 제공하는 관문이 될 것이라는 면에서 인천이 추구해야 할 정체성으로 시사하는 점이라고 본다.

• Solar Energy
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• v.15 no.1
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• pp.53-71
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• 1995

Experiments have been conducted on a planar, free surface jet of water to investigate the effects of aspect ratios(AR=6.67, 15, 26.67), average nozzle velocity($V_0=3.3m/s{\sim}78m/s$) and nozzle-to-plate spacings($Z/W=6{\sim}40$) on the characteristics of heat transfer, when 3 rectangular waterjets impinging on a flat plate which has the uniform heat flux. the scondary peaks which produced by circular jets also produced by rectangular water jets. The position of the scondary peaks depends upon the aspect ratio of nozzle. The heat transfer coefficient was subjected to the influence of aspect ratio. The heat transfer correlations and best position of nozzles which produced maximum heat transfer coefficient at stagnation point are provided.

• Journal of the Korean Applied Science and Technology
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• v.38 no.6
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• pp.1709-1721
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• 2021

This study identified the impact of career identity and career decision-making type on career preparation behavior in nursing students. The participants were 198 nursing students enrolled in the 3rd and 4th grades located in J province, and data were collected from June 14, 2021 to 27, 2021, using an online questionnaire. Data were analyzed with descriptive statistics, independent t-test, one-way ANOVA, Pearson's correlation, and hierarchical regression using SPSS/WIN 23.0 program. As a result, the mean score of career identity, rational type, intuitive type, dependent type, and career preparation behavior were 2.79(range 1~4), 3.78(range 1~5), 3.38(range 1~5), 3.01(range 1~5), and 3.51(range 1~5), respectively. Career preparation behavior was significantly correlated with career identity(r=.40, p<.001), rational type(r=.50, p<.001), intuitive type(r=.22, p=.002), and dependent type(r=-.20, p=.004). Factors influencing career preparation behavior were career identity(β=.23, p=.001), rational type(β=.31, p<.001), intuitive type(β=.27, p<.001), and dependent type(β=-.20, p=.002). These variables accounted for 24.6%p of the variance in career preparation behavior(F=11.93, p<.001). These research results suggest that it is necessary to establish a career identity and develop and apply a program that includes career guidance according to career decision-making type to improve the career preparation behavior of nursing students.