• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2001.10a
• /
• pp.154-158
• /
• 2001

산업이 고도화, 대형화됨에 따라 조선, 건설, 기계산업문야에서 대용량 힘 측정의 필요성이 날로 증가하고 있다. 힘 측정에 사용되는 힘 센서는 국가 힘 표준인 힘 표준기로부터 교정을 받아 사용함으로써 힘 측정 결과에 대해 국제적으로 인정받을 수 있다. 본 연구에서는 build-up 힘 표준기에 사용되는 build-up 힘센서를 설계 및 제작하고 힘 센서 각각의 특성과 build-up 시스템 전체의 특성을 실험하여 build-up 힘 센서의 오차를 평가하였다.

• Journal of Ocean Engineering and Technology
• /
• v.16 no.3
• /
• pp.40-45
• /
• 2002

In this study, the effects on hydraulic characteristics are discussed as the permeable underlayer thickness of the rubble mound structure changes. A series of hydraulic experiments were performed and wave run-up, reflection and set-up were investigated. Result indicated that wave run-down was affected by the water out from the permeable underlayer during down-rush. As the thickness increased, relative wave run-up decreased.

• Journal of Korean Institute of Industrial Engineers
• /
• v.25 no.1
• /
• pp.141-149
• /
• 1999

In this paper, we consider multiple-class queueing systems in which the server starts a set-up as soon as the number of customers in the "start-up class" reaches threshold N. After the set-up the server starts his service. We obtain the Laplace-Stieltjes transform and the mean of the waiting times of each class of customers for FCFS and non-preemptive priority disciplines.

• Journal of Korea Technology Innovation Society
• /
• v.4 no.1
• /
• pp.1-14
• /
• 2001

This study aims at developing some hypotheses on the politics of innovation in catching-up countries. Although innovation studies of catching-up countries have studied the process of acquisition of technological capabilities, the politics of innovation was not seriously considered in those studies. This study suggests a conceptual frame-works of the innovation politics and analyses the innovation process of mobile telecommunication system in Korea. Some hypotheses on the patterns and effects of innovation politics in catching-up countries are put forward.

• Proceedings of the IEEK Conference
• /
• 1998.06a
• /
• pp.441-444
• /
• 1998

This paper is concerned with researching latch-up immune CMOS structure was performed. By the simulation results, the connecting layer had more effect than the buried layer to latch-up immune. When the connecting layer was the dose 1*10$^{14}$ /cm$^{2}$ and the energy 500KeV, the trigger current was more 0.6mA/.mu.m and the trigger voltage was 6V. The more the connecting layer dose was lower, the more the latch-up immune characteristics was butter.

• Proceedings of the Korean Society for Technology of Plasticity Conference
• /
• 1997.03a
• /
• pp.261-264
• /
• 1997

A single action press robot, which consists of a driving unit, rotator, up-down feed base and feed bar, is developed and applied for the press automation. The driving unit is made up with a face cam and blade cam, which have a phase angle. The feeding system consists of a double speed-up apparatus and linear motion guides, and has a fast motion characteristics. A horizontal feeding speed of the feed bar is increased twice by the double speed-up apparatus. The driving mechanism could be simplified due to the speed-up of the feeding unit.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2004.05a
• /
• pp.210-210
• /
• 2004

최근 광 디스크로부터 신호를 검출하고 기록하는 핵심장치인 장 Pick-up이 점차로 고기능화, 소형화, 경량화 되면서 광 기록장치들의 발전에 크게 기여하고 있다. 초소형, 초경량 광 Pick-up을 생산하기 위해서는 광 Pick-up의 무게와 크기에 큰 영향을 미치는 렌즈의 재료를 유리에서 플라스틱으로 전환하고, 비구면 렌즈를 사용하는 것이 필요하다. 플라스틱 비구면 렌즈를 대량 생산하기 위해서 가장 많이 사용되는 방법이 사출성형이고, 소형, 경량, 휴대기능을 강조하는 제품동향으로 인하여 플라스틱 렌즈의 주요 생산기술인 사출성형의 중요성이 날로 부각되고 있다.(중략)

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2001.11b
• /
• pp.786-790
• /
• 2001

In this paper, we propose an optimum design method for optical pick-up actuators. Using this method, we can design an optimal pick-up actuator having the required tracking/focusing performances. Also, the designed actuator has the small mass, force constant for small size of magnetic circuit and large resistance for reduction of heat generation. Simulation results show that this method can be potentially implemented in all the pick-up actuators.

• Bulletin of the Korean Mathematical Society
• /
• v.56 no.5
• /
• pp.1285-1296
• /
• 2019

This paper deals with the blow-up phenomenon of solutions to a pseudo-parabolic equation with logarithmic nonlinearity, which was studied extensively in recent years. The previous result depends on the mountain-pass level d (see (1.6) for its definition). In this paper, we obtain two blow-up conditions which do not depend on d. Moreover, the upper bound of the blow-up time is obtained.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2013.05a
• /
• pp.1319-1320
• /
• 2013