• 한국철도학회논문집
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• 제8권1호
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• pp.34-40
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• 2005

This study presents parametric studies for design of a tilting mechanism to be used in 180km/h tilting train. The tilling mechanism is composed of 4 links, a lilting bolster old an electro-mechanical actuator. The movements of the tiling center, CG of the train body, coupler center and tilting actuator along variation of upper and lower span length have been verified by the kinematic analysis. Moreover, the inclination angle and the stroke of the tilting actuator according to the variation of the tilting angle from +8 degrees to -8 degrees have been investigated. From this study, the relation between the movements of the CG of the train body, coupler center and tilting actuator and the height of the tilting center could be evaluated.

• 콘크리트학회논문집
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• 제11권4호
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• pp.129-136
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• 1999

For the prediction of concrete-steel bond ability in reinforced concrete, many countries establish specifications for the pullout test. But these methods hardly to consider many parameters such as strength, shape, diameter and location of steel, concrete restrict condition by loading plate, strength of concrete and cover depth etc, and it is difficult to solve concentration and disturbance of stress. The purpose of this study is to propose a New Ring Test method which can be rational quantity evaluations of bond splitting mechanism. For this purpose, pullout test was carried out to assess the effect of several variables on bond splitting properties between reinforcing bar and concrete. Key variables are concrete compressive strength, concrete cover, bar diameter and rib spacing. Failure mode was examined and maximum bond stress-slip relationships were presented to show the effect of above variables. As the result, it appropriately expressed general characteristics of bond splitting mechanism, and it proved capability for standard test method.

• 수면정신생리
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• 제8권2호
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• pp.98-106
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• 2001

Auditory hallucinations are cardinal feature of psychosis. But the mechanism of hallucinated speech is unknown. The hypothesis that these hallucinations arise from pathologically altered brain monitoring system underlying speech perception is influential. With the help of rapidly developing neuroimaging study technologies, many researchers have been finding new organic deficits in the hallucinated schizophrenic patient's brain. In this article, we reviewed the general appearance of hallucination, a computer simulation model of hallucination and several neuroimaging study findings on hallucinating schizophrenic patients. In conclusion, we presented the presumptive mechanism of hallucination based on the anatomical dysfunction of schizophrenia.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 하계학술대회 논문집 B
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• pp.804-806
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• 2003

In these days the Vacuum Circuit Breaker(VCB) is used in most medium voltage level because VCB has merits of simple structure, long life, free maintenance and environment friendly characteristics. Most of VCBs adopt mechanical spring drive mechanism to operate vacuum interrupter, but this mechanism is composed of many components and needs frequent maintenance works. In this paper, we study about the VCB drive mechanism with Permanent Magnet Actuator (PMA). Design methods and design flows about PMA are presented. The magnetic equivalent circuit is used for elementary and detailed design to determine the size of PMA. Finite Element Method (FEM) analysis is performed to evaluate the behavior characteristics of PMA in both static and transient state. Finally we manufacture sample PMA and verify FEM analysis through experiments.

• 반도체디스플레이기술학회지
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• 제17권4호
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• pp.6-10
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• 2018

Organic light emitting devices have attracted the attention of many people because of their high potential for self-emission and flexible display devices. However, due to limitations in device efficiency and lifetime, partial commercialization is underway. In this paper, we have investigated the electrical conduction mechanism of the organic light emitting device by the temperature and the thickness of the light emitting layer through the current - voltage characteristics with respect to the conduction mechanism directly affecting the efficiency and lifetime of the organic light emitting device. Through the study, it was found that the conduction in the low electric field region is caused by the movement of the heat excited charge in the ohmic region and the tunneling of the electric charge due to the high electric field in the high electric field region.

• 국제지역연구
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• 제22권4호
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• pp.77-98
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• 2018

본 논문의 목적은 제조업, 특히 철강기업의 공급망 경쟁력 확보를 위한 최적의 메커니즘 사례를 연구함으로서 그 시사점을 찾고자 하는 것이다. 이를 위해 본 논문에서는 국내 대표 글로벌 철강그룹의 계열사를 대상으로 그 사례를 살펴보았다. 지금까지의 기업 전략연구는 주로 대형 그룹사의 모기업을 중심으로 이루어져 왔으나, 이번에는 대그룹 계열사에 대한 전략적 한계점과 특성을 고려하여 ser-M기반에서 공급망관리 메커니즘을 다루도록 하며, 이를 통해 글로벌 철강업체 및 대기업 계열사에 적절한 메커니즘을 탐색해보고자 한다. 연구결과, 대기업 그룹의 계열사는 그룹 모기업의 필요에 의해 건립되는 경우가 많아 모기업(S) 중심의 메커니즘이 작동되기 쉽다. 따라서 계열사 입장에서 통제 가능한 내부 자원(R)을 최대한 활용하는 메커니즘이 적합한 것으로 나타났다. 본 논문의 ser-M기반 공급망 메커니즘 연구는 글로벌 철강 제조업 공급망 사례를 중심으로 메커니즘을 살펴보았다는데 의미가 있으며, 또한 국내 대표그룹 계열사에 대한 사례연구란 점에서 그 의의를 찾을 수 있다.

• Journal of Biosystems Engineering
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• 제31권2호
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• pp.88-94
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• 2006

The market of rice transplanter has already been changed for riding and to be turned large size of chassis. Because an automation is rapidly expanded, It is strongly need to analyze a mechanism and develop a hydraulic circuit. In this study, we analyzed the mechanism of working equipment of rice transplanter for riding and developed hydraulic circuits. We proposed the operating mechanism of rice transplanter for riding through the mechanistic analysis of working equipment. And the simulation and experiment were performed. In order to up and down the working equipment of rice transplanter for riding, we designed the mechanism which was installed hydraulic circuit and hydraulic cylinder, and it was manufactured. The pressure of developed hydraulic circuit was set by 800 $N/cm^2$. In the field testing, the hydraulic response presented at 50 msec in the maximum driving velocity, 0.8 m/sec of rice transplanter for riding, and it was well performed. The results of experiments showed the system characteristics sufficient to use as the hydraulic mechanism for a rice transplanter for riding.

• 한국정밀공학회지
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• 제23권4호
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• pp.132-138
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• 2006

A tape feeder is an important part to supply a micro chip such as 1005 and 0603 components in SMT process. Traditional sprocket wheel type feeder has several problems such as backlash and indexing errors, low compatibility and confidence. However, it is very difficult to solve such problems due to the inevitable fraction defectives of sprocket wheel. Thus, the object of this works is to develop a linear type high precision tape feeding system using cam-slider mechanism. The proposed cam-slider mechanism is composed of several links and a plate, pneumatic actuator is used to generate linear motion. The proposed mechanism has distinct advantages over the conventional mechanism. It has reduced feeding errors, long lift-cycle, and slim width. As a result, the developed tape feeder using cam-slider mechanism shows special characteristics far high precision feeding for chip-mounters.

• 한국군사과학기술학회지
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• 제21권3호
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• pp.331-341
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• 2018

This study proposes an integrated serial spring-damper mechanism as a dual pulse generation system. Compared to the traditional dual pulse generation system, which used multiple springs and a damper to generate a dual pulse critical for impact testing of naval equipments, currently used separated serial spring-damper mechanism is comprised of two components: an air spring, and a damper. The proposed mechanism combines the two components into one integrated system with a unique design that lets simply changing the volume and the pressure of the air tank, and the length of the annular pipe adjust the stiffness and damping constants for testing, eliminating the need to have multiple sets of air springs and dampers. Simulations using MatLab and Simulink were conducted to verify the feasibility of this design. The results show the potential of an integrated serial spring-damper mechanism as a more convenient and flexible mechanism for dual pulse generation system.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2006년도 춘계학술대회 논문집
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• pp.485-486
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• 2006

This paper represents a ultra precision rotational device where the smooth impact drive mechanism(SIDM) is utilized as a driving mechanism. Linear motions of piezoelectric elements are converted to the rotational motion of disk by frictional forces generated between the rotational disk and the friction bars which are attached to the piezoelectric elements. This device was designed to drive a rotational disk using slip-slip motion mechanism based on stick-slip motion mechanism. Experimental results show that the angular velocity was increased in proportion to the magnitude of supplied voltage to piezoelectric element. In our device, the smooth rotational motion was obtained when the driving frequency has been reached to 500Hz under the driving voltage of 100V. The amount of step movement has been revealed to be $3.44{\times}10^{-4}$ radian.