• 제어로봇시스템학회:학술대회논문집
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• 1996.10b
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• pp.718-721
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• 1996

In this work, an effective stiffness generated by internal loading for a planar 3 degrees of freedom RCC mechanism is investigated. For this purpose, the internal kinematic analysis and antagonistic stiffness modeling for this mechanism are performed. It is shown that the antagonistic stiffness could be effectively created at the center of the mechanism in its symmetric configuration.

• Proceedings of the Membrane Society of Korea Conference
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• 1991.04a
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• pp.38-39
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• 1991

비대칭 다공막은 자체로서 UF혹은 MF용으로 사용될 뿐만 아니라 RO혹은 기체분리용 복합박막의 지지막으로도 사용되기 때문에 비대칭다공막 제조기술은 분리막의 제조에 가장 중요한 것 중의 하나이다. 대부분의 비대칭 다공막은 상반전법에 의하여 제조되며, 상반전법은 균질 고분자용액이 비용매 속에서 두개의 용액상 (고분자 농후 및 희박용액상)으로 분리된 후 비대칭다공막으로 되는 과정을 일컫는다.

• Korea Petroleum Association Journal
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• no.8 s.102
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• pp.8-9
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• 1989

• Korea Petroleum Association Journal
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• no.8 s.126
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• pp.42-46
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• 1991

• The monthly packaging world
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• s.85
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• pp.154-161
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• 2000

• 해운
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• no.8 s.30
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• pp.40-40
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• 2006

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.30 no.7
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• pp.20-28
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• 2002

In this paper, the aerodynamic performance prediction of a 30kW counter-rotating (C/R) wind turbine system has been made by using the momentum theory as well as the two-dimensional quasi-steady strip theory with special care on the wake and the post-stall effects. In order to take into account the wake effects in the performance analysis, the wind tunnel test data obtained for a scaled blade are used. Both the axial and rotational inductions behind the auxiliary rotors are determined through the wake model. In addition, the optimum chord and twist distributions along the blades are obtained from the Glauert's optimum actuator disk model considering the Prandtl's tip loss effect. The performance results of the counter-rotating wind turbine system are compared with those of the conventional single rotor system and demonstrated the effectiveness of the counter-rotating wind turbine system.

• Geophysics and Geophysical Exploration
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• v.18 no.1
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• pp.9-13
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• 2015

All the resistivity data contain various kinds of noise. The major sources of noise in DC resistivity measurement are high contact resistance, measurement errors, and sporadic background noise. Thus, it is required to measure data noise to accurately interpret resistivity data. Reciprocal measurements can provide a measure of data precision and noise. In this study, we proposed a data-weighting method from reciprocity measurement. Furthermore, a data-weighting method using both the reciprocity error and data-misfit in the inversion process was studied. Applying the data-weighting method to the inversion of 3D resistivity data, it was confirmed that local anomalies are slightly suppressed in the final inversion results.

• The Korean Journal of Financial Management
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• v.15 no.2
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• pp.163-181
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• 1998

본 연구는 Tobin-Q 비율(이하 토빈 Q, 또는 Q)을 이용하여 합병제의기업과 피합병대상기업을 합병전 경영성과의 우열에 따라 분류하고, 분류 집단별 초과수익률을 측정 검증함으로써 합병전 후의 합병관련기업의 합병효과를 분석하였다. 실증분석 결과를 보면 합병제의기업과 피합병기업 모두 합병 공시 후 양의 초과수익률을 얻는 것으로 나타났으며, 합병제의기업은 토빈 Q가 낮을수록 합병성과가 크게 나타났고, 피합병대상기업은 토빈 Q가 높을수록 합병성과가 크게 나타났다. 또한 합병제의기업과 피합병대상기업의 토빈 Q를 동시에 고려한 경우에는 합병제의기업의 Q가 높고 피합병대상기업의 Q가 낮으면, 합병성과가 작았고, 합병제의기업의 Q가 낮고 피합병대상기업의 Q가 높으면 합병성과가 높게 나타난다는 경향을 관찰할 수 있었다. 이러한 연구결과는 경영성과가 좋은 합병제의기업이 대체적으로 이득을 보지만, 경영이 부실한 피합병대상기업을 인수할 때 더 많은 이득을 본다는 Lang, Stulz, Walkling(1989)의 연구결과는 상반되는 것이다. 또한 경영성과가 나쁜 기업을 합병함으로써 보다 많은 합병가치 창조가 가능하다는 Servaes(1991)의 연구결과와도 상반되는 것이다. 이러한 상반된 결과는 우리나라 현실에서 합병이 대개는 계열그룹내, 또는 지배회사와 피지배회사간의 합병이 주류를 이루고, 세법상 합병기업의 손실은 승계되지만 피합병기업의 손실은 승계되지 않으므로 형식상 합병제의기업과 피합병대상기입이 뒤바뀌는 경향이 많다는 점에서 그 원인을 추정할 수 있다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.10
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• pp.270-276
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• 2019

According to the International Maritime Organization (IMO) 2020 Regulation, ships operating outside designated emission control areas (ECA) have to use low-sulfur oil with a sulfur content of 0.5% or less by January 2020. To minimize the consumption of high-priced low-sulfur oil, it is urgent to introduce efficient energy-saving devices (ESD), and contra-rotating propeller (CRP) systems are well known to be the most effective one. The shafting system that drives a CRP is composed of an inner shaft and an outer one and has a mutually influential system that is much more complex and heavier than a general shafting system. An initial design was carried out to install a CRP system for the first time in Korea. The purpose of this study is to verify whether the journal bearing meets the classification's design criteria through a bearing reaction force analysis for the classification's approval of the initial design. It is ideal for the thrust of the propeller to act on the center of the shaft, but thrust eccentricity occurs due to the uneven wake caused by the stern shape. Load conditions were applied while considering thrust eccentricity to perform the shaft analysis, and the results were compared with the classification's criteria.