• 한국경제지리학회지
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• 제10권1호
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• pp.1-18
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• 2007

본 연구에서는 개방경제체제로 전환되는 과정에서 울산이 가질 수 있는 시스템 전환의 가능성에 기초해서 울산 자동차클러스터의 발전방향을 탐색하고 바람직한 전략적 개입의 방향을 제시하고자 했다. 울산의 자동차 클러스터의 조건을 탐색하기 위해 생산 및 연구개발 네트워크의 글로벌 차원, 국가 차원, 지역 차원의 공간적 특성에 대하여 분석하였다. 그리고 현대자동차가 울산공장을 설립하면서 시작된 울산의 자동차 산업의 집적과정의 특징과 그 동안 축적한 역량에 대한 분석에 기초해서 대안적 발전경로를 탐색하고 정책적 시사점을 도출하였다.

• 소성∙가공
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• 제11권3호
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• pp.246-254
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• 2002

A simple method to derive an optimal pressure curve, characterized by initial pressure, final pressure and pressure path, has been proposed. The initial pressure has been determined from the condition to prevent recoiling phenomenon in the early stage, while the final pressure is from the FE analysis and pressure path is from the punch penetration volume. In order to realize the pressure curve, an open loop control system based on a proportional relief valve has been developed for the renovated CNC hydroforming press. Through the comparison of experiment and analysis, the predicted pressure curve has been verified optimal curve since no defect has been observed.

• 한국화재소방학회:학술대회논문집
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• 한국화재소방학회 2011년도 추계학술논문발표회 논문집
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• pp.318-323
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• 2011

대규모 화재실험 또는 실제 화재에서 발생되는 독성가스의 분석은 화재가스에 대한 샘플링, 시료전처리, 분석데이터 처리 등의 여러 가지 문제로 인해 측정이 불가능하였다. 본 논문에서는 개방형 FT-IR 장비를 활용하여 대공간에서 발생되는 유해가스를 직접적인 접촉 없이 원거리에서 검출하는 실험적 연구를 수행하여 측정 가능성을 입증하였다.

• 아동학회지
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• 제21권4호
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• pp.105-121
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• 2000

This research focused on the cause and effect relationship between various factors related to teen-age pregnancy. A total of 130 unwed mothers were interviewed regarding details of their pregnancies. Path analysis showed that knowledge of contraception and premarital sexual attitudes were the important factors affecting the premarital sexual behaviors directly. It was also shown that the sexual attitudes of friendship groups indirectly affects premarital sexual behaviors through the path of the premarital sexual attitudes. When sexual attitudes of the friendship group is open, premarital sexual attitudes become open, causing the increase in premarital sexual behaviors. Premarital sexual behaviors and the knowledge of contraception did not have a statistical effect on the number of pregnancies.

• The Journal of Asian Finance, Economics and Business
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• 제7권6호
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• pp.409-416
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• 2020

The research has been conducted to explore the combination of three intangible resources, including social capital, entrepreneurship, and resilience capability on the performance of State Capital Enterprises (SCEs) in Vietnam. Both qualitative and quantitative approaches are applied in the study. An in-depth interview of ten CEOs at SCEs in Vietnam was made to explore new indicators for the contextual latent variables in the research models. By employing the data from the authors' survey of 568 SCEs in Vietnam in 2019, using Cronbach's alpha, confirmatory factor analysis (CFA) and path analysis (SEM), the mechanism that social capital impacts on SCE performance has been analyzed. In addition to the direct role, social capital indirectly affects corporate performance through entrepreneurship and resilience capability. It was found that social capital has a larger impact on entrepreneurship than resilience capacity. However, the contribution of resilience capacity to the firm performance is much more than the entrepreneurship's in Vietnamese context. This study enriches the theory by proposing a measurement scale of the contextual latent variables as a result of in-depth interviews with experts using a qualitative analysis technique. In addition, the path analysis findings suggest practical implications for managers to effectively use their resources in SCEs.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2009년도 춘계학술대회 논문집
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• pp.114-117
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• 2009

In this work, closing behavior of the voids generated in a casting process was investigated for various parameters such as reductions in height void size and billet rotation during hot open die forging process. The reduction in height and path schedule including the number of paths and billet rotation were chosen as key process variables to express the change of geometrical void shape and void closing behavior. On the other hand, values of die overlapping and die width ratio were set to be constant. Extend of void closure was observed and evaluated using tensile test and microscope. Based on the experimental result, it is ensured that void closure do not occur at 15% and 30% reduction in height as well as one or two rotations of a billet. The useful datum obtained from this study could be utilized to establish an optimum path schedule in the open die forging process.

• 한국콘텐츠학회:학술대회논문집
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• 한국콘텐츠학회 2014년도 춘계 종합학술대회 논문집
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• pp.19-20
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• 2014

• Journal of Mechanical Science and Technology
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• 제17권11호
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• pp.1616-1627
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• 2003

This paper describes a mini linear optical pickup actuator. To reduce the size, inner yokes are designed to guide the mover and outer yokes of permanent magnets are removed. Magnetic circuit method is used to determine the thrust force. Virtual path method is proposed to analyze the open magnetic circuit analysis. The magnetic circuit of the proposed actuator can be a closed circuit due to the virtual path model of the outer magnetic flux. The validity of virtual path method is evaluated by comparing to the FEM analysis. Structural vibration is investigated using FEM and the design of the mover is modified to improve the vibration characteristic. Dynamic characteristic experiments shows that the performance of the proposed actuator is enough to be used as a coarse and fine seeking actuator simultaneously and the thrust force margin for loading a focusing actuator is guaranteed.

• 한국정밀공학회지
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• 제27권7호
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• pp.36-48
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• 2010

This paper is concerned with stereo vision-based approach to detect obstacles and to generate the path of destination from the start. The hexapod robot in the experiment is cable of walking by legs and driving by wheels simultaneously. The hexapod robot operates under the driving mode normally, and it changes driving mode to walking mode to overcome obstacles using its legs. Disparity map, which is the correlation between two images taken by stereo camera, is employed for calculation of the distance between the robot and obstacles. When the obstacles information is extracted from the disparity map, the potential field algorithm is applied to create the obstacle-avoidance path. Simulator, based on OpenGL, is developed to generate the graphical path, and the experimental results are shown for the verification of the proposed algorithm.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2007년도 추계학술대회 논문집
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• pp.47-48
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• 2007