• Journal of Korea Society of Industrial Information Systems
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• v.14 no.4
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• pp.16-29
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• 2009

This paper investigates the kinematic and dynamic analysis of a spherical three degree of freedom parallel joint module, which is used in the exercise equipment for balance and leg-strength improvement of aged people. The joint module has three dyads which consist of two links and three revolute joints, and their all joints intersect at the global point located at the module's center. The paper shows the explicit mathematical procedure for deriving the closed form solutions in the inverse and forward position analysis of this parallel joint module. In velocity and acceleration analysis, we derived relations for joint velocities and accelerations of dyads and rotational velocity and acceleration of the top plate. For applying this module to rehabilitation exercise, we determined the dynamic model of the Korean males in their 50s and examined the model's results by dynamic model simulation.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.41 no.4
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• pp.30-39
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• 2023

This study aims to identify the value of Incheon Freedom Park as a 'historic urban park' through the historical transition process of the park and surrounding areas. To this end, this study uses a time series analysis, as research method, based on old maps and aerial photographs to investigate the changes in the park over time and to interpret them based on the historical and cultural changes in modern and contemporary history. As a result of the study, the park not only has (1) evidence of major events in modern and contemporary history, but also (2) historical value as an urban park based on the first urban plan in Korea, and (3) very important heritage value that shows the rapidly changing civic life in modern and contemporary times. However, despite the identification of heritage values in this study, further research is needed to explore and excavate in-depth data on the park in order to more clearly identify, restore, and utilize the heritage values of the park.

• Journal of Korea Port Economic Association
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• v.31 no.4
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• pp.107-120
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• 2015

This study analyzes Korea's Free Economic Zone (FEZ), by particularly focusing on Incheon and Busan-Jinhae zones, using the Analytic Hierarchy Process (AHP) method and a questionnaire survey analysis. The study compares important selection criteria and satisfaction of resident companies in Incheon and Busan-Jinhae FEZs. The findings are as follows. First, the AHP method results suggest that companies in both Incheon and Busan-Jinhae FEZs are affected by location, economic society, and policy. In subordinate determining factor for land, it is ordered by ease of gaining land, inexpensive rental fee in Incheon and by convenient access to close markets and inexpensive rental fee in Busan-Jinhae. Second, the questionnaire survey results suggest high adjacent market size and easy access in Incheon FEZ and sound logistics infrastructure in Busan-Jinhae FEZ. For this reason, Incheon has a high value of logistics infrastructure and potential market near metropolitan area and Busan-Jinhae, has a high value of transportation Infrastructure near industrial district. These findings will contribute to policy data for activating and promoting the Free Economic Zone.

• Journal of Korean Library and Information Science Society
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• v.47 no.4
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• pp.93-122
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• 2016

The present study investigates librarians perceptions of Free Learning Semester, and their commitment to program development for coordination with Free Learning Semester, and whether they currently offer programs for Free Learning Semester. The study results are as follows. First, the results on perceptions of Free Learning semester showed that 54.20% of the librarians who participated in the study were aware of Free Learning Semester, and 80.15% had participated in training related to Free Learning Semester. Regarding the anticipated outcomes of implementation of Free Learning Semester, "Participation in various experiential activities offered through Free Learning Semester" was the most common response, and regarding special considerations in Free Learning Semester, "Need for instituting the dedicated workforce and enhancing their sense of responsibility and expertise" was the most common response. Second, regarding the library program development and provision for coordination with Free Learning Semester, 58.02% thought that the implementation of Free Learning Semester was an opportunity to expand the role of libraries, while insufficient budget was listed as a barrier. In addition, 63.36% stated that they had no experience in providing a program in a library. Finally, the results on the perception on the Free Learning Semester program they want to provide in a library showed that "Human Library" and "Read! Think! Dream!" were the programs they want to provide most, with the mean score of 3.939.

• Journal of the Korean Magnetics Society
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• v.14 no.6
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• pp.236-239
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• 2004

We studied the specular spin valve (SSV) having the spin filter layer (SFL) in contact with the ultrathin free layer composed of Ta3/NiFe2/IrMn7/CoFel/(NOLl)/CoFe2/Cu1.8/CoFe( $t_{F}$)/Cu( $t_{SF}$ )/(NOL2)/Ta3.5 (in nm) by the magnetron sputtering system. For this antiferromagnetic I $r_{22}$M $n_{78}$-pinned spin filter specular spin valve (SFSSV) films, an optimal magnetoresistance (MR) ratio of 11.9% was obtained when both the free layer thickness ( $t_{F}$) and the SFL thickness ( $t_{SF}$ ) were 1.5 nm, and the MR ratio higher than 11% was maintained even when the $t_{F}$ was reduced to 1.0 nm. It was due to increase of specular electron by the nano-oxide layer (NOL) and of current shunting through the SFL. Moreover, the interlayer coupling field ( $H_{int}$) between free layer and pinned layer could be explained by considering the RKKY and magnetostatic coupling. The coercivity of the free layer ( $H_{cf}$ ) was significantly reduced as compared to the traditional spin valve (TSV), and was remained as low as 4 Oe when the $t_{F}$ varied from 1 nm to 4 urn. It was found that the SFL made it possible to reduce the free layer thickness and enhance the MR ratio without degrading the soft magnetic property of the free layer.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2009.10a
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• pp.141-142
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• 2009

• Journal of Welding and Joining
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• v.22 no.4
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• pp.20-23
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• 2004

마이크로 레이저접합은 열원으로 레이저(Light Amplification by Stimulated Emission of Radiation)를 사용함으로써 에너지 밀도를 조절할 수 있고 비접촉식 프로세스라는 특성을 가지고 있다. 따라서 제품 디자인의 자유도를 극대화시킬 수 있으며 고출력 레이저를 사용할 경우 생산단가를 낮출 수 있다는 장점이 있다.(중략)

• Proceeding of EDISON Challenge
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• 2017.03a
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• pp.596-600
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• 2017

이 논문에서는 1자유도 시스템이며, DC모터로 간단히 구동 가능한 로봇으로, Jansen Mechanism을 사용한 4족보행 로봇을 설계 및 제작하고, 센서를 사용한 탐사 수행의 예시로 라인 트레이싱을 구현, 성능 테스트를 통해 차기 연구용 및 단가가 낮은 대량 생산형 로봇으로서의 가능성을 검증한다.

• Magazine of the Korea Institute for Structural Maintenance and Inspection
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• v.17 no.4
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• pp.27-35
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• 2013

• 한국해양학회지
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• v.30 no.4
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• pp.365-370
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• 1995

A new piston-type Free-fall corer (FFC) was developed for the sampling of core sediments in aquatic environments. The corer, named "KORDI-FFC", is the modified sampler of the existing FFX with an open barrel gravity corer. It was rested successfully on the muddy bottom in the Chinhae Bay and on the sandy bottom (Mz=3$\phi$) in nearshore areas around the Cheju Island. Several merits found in the unstrument are; $\circled1$ operation on a small vessel without winch and cable, $\circled2$ low cost of construction, $\circled3$ little disturbance of surface sediments during the sampling, $\circled4$ short round-trip time of sampling, and $\circled5$ simultaneous performance of other research works during the lowering of FFC.