• 한국철도학회논문집
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• 제17권4호
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• pp.228-232
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• 2014

철도의 무선전력전송 시스템을 구현하는데 있어 급전선로에서 생성된 자기장은 레일에 유기전압을 형성한다. 레일의 유기전압은 궤도회로의 동작 및 안전사고에 영향을 줄 수 있기 때문에 최소화하는 것이 필요하다. 본 논문에서는 3가지 무선전력전송 선로에 대해서 레일에 형성되는 유기전압의 관계를 시뮬레이션을 통하여 살펴보고 레일 유기전압을 줄이기 위한 급전선로의 자기장 분포를 제시한다.

• Journal of applied mathematics & informatics
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• 제6권3호
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• pp.915-920
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• 1999

We showed the upper p-estimate and p-power concavity are the necessary and sufficient condition of the space $M_{\Psi}$to be weak $L_pX>.

• 경영과정보연구
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• 제30권4호
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• pp.475-509
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• 2011

본 연구는 우리나라 195개의 기업을 대상으로 세계적으로 관심의 대상이 되고 있는 노동시장의 유연성 전략 즉 수량적 유연성과 기능적 유연성이 조직의 결과변수인 생산성, 노사협력성, 고용안정 등에 어떠한 영향을 주는가를 기업 단위로 분석하였다. 또한 노동시장 유연성(수량적 유연성 및 기능적 유연성)과 노사협력성 및 고용안정간의 관계에서 노조 힘의 조절역할에 대해서도 분석하였다. 결과는 수량적 유연성은 생산성, 노사협력성, 고용안정 등과 유의한 관계를 보여주지 않았으나 기능적 유연성은 생산성, 노사협력성, 고용안정 등에 상당한 정의관계를 보여 주었다. 이러한 결과는 기업의 노동시장 전략에서 기능적 유연성의 중요성을 다시 확인할 수 있다. 서구에서는 기능적 유연성의 중요성을 지속적으로 주장하고 수량적 유연성의 문제점을 지적하고 있다. 그러나 본 연구에서는 기능적 유연성의 긍정적 측면은 확인이 되었으나 수량적 유연성의 부정적 관계가 확인될 수 없었다는 점에서 이들 관계는 앞으로 좀 더 연구가 지속되어야 하는 과제도 남겼다. 노동시장 유연성과 노사협력 및 고용안정과의 관계에서 노조 힘의 조절역할에 대한 분석결과는 수량적 유연성과 노사협력성 관계에서만 노조 힘의 상호작용 효과가 확인되었다. 이러한 결과는 노조의 기회주의적 행동에 대한 가능성을 엿볼 수 있다. 이러한 결과에 대한 논의를 할 것이다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2005년도 제17회 워크샵 및 추계학술대회
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• pp.545-548
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• 2005

There is a close relation between the heat generation in the fuel cell stack and the fuel cell performance. In PEM fuel Gell vehicles, the stack coolant temperature is about $65^{\circ}C$, which is far lower than that for general automobile engine. Therefore, it is hard to release heat generated in the stack by using a radiator of limited size because of the reduced temperature difference between the coolant and the ambient air. In this study, indirect stack cooling system using $CO_2$ heat pump was designed and its stack cooling performance in releasing heat to the ambient was investigated. This work focuses on a series of processes that grasp the relation among the fuel cell power, the radiator capacity and the stack temperature. The purpose of this work is to find out a way to properly release sufficient amount of heat through the finite sized radiator, so that the stack power general ion can not be deteriorated due to the stack temperature increase. The optimization between the compressor power consumption and the fuel cel1 output power can be carried out to maximize the performance of fuel cell system.

• 신재생에너지
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• 제1권4호
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• pp.49-54
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• 2005

There is close relation between the heat generation in the fuel cell stack and the fuel performance. In PEM fuel cell vehicles, the stack coolant temperature is about $65^{\circ}C$, which is far lower than that for general automobile engine. Therefore, it is hard to release heat generated in the stack by using a radiator of limited size because of the reduced temperature difference between the coolant and the ambient air. In this study, indirect stack cooling system using $CO_2$ heat pump was designed and its stack cooling performance in releasing heat to the ambient was investigated. This work focuses on a series of processes that grasp the relation among the fuel cell power, the radiator capacity and the stack temperature. The purpose of this work is to find out a way to properly release sufficient amount of heat through the finite sized radiator, so that the slack power generation can not be deteriorated due to the stack temperature increase. The optimization between the compressor power consumption and the fuel cell output power can be carried out to maximize the performance of fuel cell system.

• 한국소음진동공학회논문집
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• 제14권8호
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• pp.668-674
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• 2004

The possibility of global noise reduction by the sound power control through selection of distribution and impedance of absorptive materials is discussed. It is necessary to investigate the relation between the global sound energy in the field and the total sound power radiated by sources. In the previous work,$^{(1.2)}$ the authors presented a useful design method to change boundary condition that can be useful to reduce noise in acoustically small enclosures. Changing boundary condition Is related to not only enclosure’s geometrical shape but also acoustical treatment on walls for example, attaching of impedance patches (ex: absorptive material). In many practical situations, we often meet situation to change acoustical treatment on walls. The possibility of total acoustic potential energy(globa1 noise) reduction by acoustic source power control is examined in an acoustically small cavity Using acoustic energy balance equation, the relation between global noise control performance and absorptive material’s arrangement/impedance is deduced. Numerical simulation is performed to interpret its physical meaning in terms of absorbent’s distribution and impedance.

• 대한물리의학회지
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• 제4권4호
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• pp.209-214
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• 2009

Purpose：The purpose of this study are analysis characteristic of grasping power with each different elbow flexion degree and grasping power with each different elbow each different hand position and announcement. Methods：Measuring about 10cm wide open position with both feet for each elbow in the line positions of the $0^{\circ}$, $45^{\circ}$, $90^{\circ}$, $135^{\circ}$, and forearm position of supination, mid position, pronation is of the order. Results：The averge position of maximal grip strength was $0^{\circ}$ of elbow flexion with mid position in male and $90^{\circ}$ of elbow flexion with mid position in female. Grip strength in change of wrist position according to elbow flexion was significant difference(P<0.05). Grip strength in change of wrist position according to elbow flexion by sex was significant difference(P<0.05) Conclusion：When the elbow has flexion with $0^{\circ}$, $45^{\circ}$, $90^{\circ}$, $135^{\circ}$ then grasping power has a intimate relation with forearm position. Grasping power with forearm supination, pronation and mid position also has a intimate relation with elbow flexion.

• 천문학회보
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• 제42권1호
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• pp.29.3-29.3
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• 2017

We study the connection between the observed star formation rate-stellar mass (SFR-M) relation and the evolution of the stellar mass function (SMF) by means of a Subhalo Abundance Matching technique coupled to merger trees extracted from a N-body simulation. Our approach, which considers both galaxy mergers and stellar stripping, is to force the model to match the observed SMF at redshift z>2, and let it evolve down to the present time according to the observed (SFR-M) relation. In this study, we use two different sets of SMFs and two SFR-M relations: a simple power law and a relation with a mass-dependent slope. Our analysis shows that the evolution of the SMF is more consistent with a SFR-M relation with

• 전력전자학회:학술대회논문집
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• 전력전자학회 2017년도 전력전자학술대회
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• pp.180-181
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• 2017

Recently as distributed source has increased, the distribution system has changed from unidirectional power flow to bi-directional power flow. This power flow causes the PCC voltage variation, which can adversely affect voltage sensitive loads. In this paper, the relation between the active power, reactive power and PCC voltage of the distributed source is analyzed, and the PCC voltage control scheme by reactive power compensation is proposed in the distributed source itself. In addition, limitations and conditions according to the standard for interconnecting distributed resources are specified and verified through simulation.

• 한국간호교육학회지
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• 제26권3호
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• pp.290-298
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• 2020

Purpose: This study aimed to grasp the correlation between communication ability, empathy, and interpersonal relations among nursing students, and to explore the mediating effect of empathy on the relation between communication and interpersonal relation in nursing students. Methods: Participants were 209 college students in the Department of Nursing at two universities. The data collection period was from October 1, 2019 to November 1, 2019. The questionnaire consisted of measuring tools for general characteristics, communication ability, interpersonal relation and empathy. SPSS/23.0 program was used. The analysis used descriptive statistics, Pearson's correlation coefficient, independent t-test, one-way ANOVA, multiple regression analysis, and Sobel's tests. Results: The communication ability was nursing major satisfaction (t=8.25, p<.001), and last year's average grade (t=7.29, p=.001). Interpersonal relationships showed significant differences in gender (t=2.51, p=.013) and nursing major satisfaction (t=10.99, p<.001). Communication ability and empathy (r=.37, p<.001), communication ability and interpersonal relation (r=.77, p<.001), empathy and interpersonal relation (r=.43, p<.001) showed a significant static correlation. In communication ability and interpersonal relation, empathy had a partial mediating effect (Z=2.97, p<.001), and explanatory power was 62%. Conclusion: To improve the communication ability and interpersonal relation of nursing students, it is necessary to develop a personalized and empathy-enhanced education program for each grade.