• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.05a
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• pp.125-125
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• 2004

최근에 급속히 발달하고 있는 나노 기술(NT)파 생명공학 기술(BT)로 인해 미세한 영역에서의 역학적 측정이 중요시되고 있다. 질량, 힘, 온도, 압력 등의 기본적인 물리량들의 정확한 측정이 거시세계와 마찬가지로 나노 물질의 제조, 현상의 규명에 필수적인 요건이기 때문이다. 이중에서 미세 힘측정은 나노 압입 시험, 탄소나노튜브의 기계적 특성측정, MEMS 구조물의 특성평가, 근육 세포의 근력측정, DNA나 생체 분자력 측정 등 광범위하게 사용되고 있다.(중략)

• Transactions of the Korean Society of Mechanical Engineers A
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• v.24 no.3 s.174
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• pp.667-675
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• 2000

Force measuring devices should be calibrated to guarantee their test results. In order to establish the force standards in Korea, deadweight machines of 5 kN, 20 kN, 100 kN and 500 kN capacity and a hydraulic force standard machine of 2 MN capacity were installed at the Korea Research Institute of Standards and Science(KRISS). As heavy industries in Korea have been developed, we should measure large forces over 2 MN capacity precisely in industries. We developed a 10 MN force standard machine with built-in force transducers which is more compact and cheaper than hydraulic force standard machines which have been widely used as large force standards in most national metrology laboratories. Test results reveal that the relative expanded uncertainty of the force machine is less than 4.1 $\times$ 10-4 in the range of 1 MN-4.5 MN.

• Journal of the KSME
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• v.32 no.12
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• pp.1038-1048
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• 1992

오늘날 자동차에 요구되는 조건은 힘(출력), 안전성, 경제성(연비) 및 저 공해성이다. 아무리 힘이 좋고 안전하게 만들어졌다 하더라도 연료가 많이 소비되면 소비자들로부터 호감을 얻을 수 없 으며 공해를 많이 배출하게 되면 법에 의해 도로상을 주행할 수 없게 된다. 그러므로 오늘날 자동차 제작사는 저공해, 고연비자동차 개발에 온갖 힘을 쏟고 있다. 오늘날 자동차는 오염물질의 배출을 저감시키기 위하여 엔진개량, 연료개량 및 후처리기술을 적용하고 있지만 자동차의 급 격한 증가에 따라 연료소비량이 증가하고 아울러 오염물질의 배출량이 증가하여 대기를 오염시 킨다. 여기서는 자동차의 연료소비량을 감소시키기 위한 대책의 일환으로 실시하고 있는 정부 공인 표준연비에 대하여 알아보고 오염물질 배출량과의 관계 및 연비 향상대책에 대하여 고찰 해보고자 한다.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.10a
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• pp.59-62
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• 2005

Small force measurements ranging from 1 pN to $100{\mu}N$, we call it Nano Force, become the questions of common interests of biomechanics, nanomechanics, material researches, and so on. However, unfortunately, quantitative and accurate force measurements have not been taken so far. This is because there ,are no traceable force standards and a calibration scheme. This paper introduces a quantitative force metrology, which provides traceable link to SI (International Systems of Units). We realize SI traceable force ranging from 1 nN to $100{\mu}N$ using an electrostatic balance and disseminate it through transfer standards, which are self-sensing cantilevers that have integrated piezoresistive strain gages. We have been built a prototype electrostatic balance and Nano Force Calibrator (NFC), which is an AFM cantilever calibration system. As a first experiment, we calibrated normal spring constants of commercial AFM cantilevers using NFC. Calibration results show that the spring constants of them are quite differ from each other and nominal values provided by a manufacturer (up to 240% deviation).

• Journal of the Korean Society for Precision Engineering
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• v.11 no.5
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• pp.33-41
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• 1994

For the establishment of large force standard and the accurate measurement of large force, 2MN hydraulic force standard machine which consists of loading frame, deadweight machine, two ram/cylinder systems and hydraulic control system was designed and fabricated. Measurement results of shapes for tow ram/cylinders reveal that the ratio of effective area is 200.094. The relative deviation of force stability for the machine is about .+-. 0.01% at 2MN and is less than .+-. 0.005% below 2MN. This machine may be widely used to calibrate the force measuring devices in industry and to test the force sensors.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.39 no.6
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• pp.34-43
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• 2002

This paper deals with a standard cell placement which is based on a quadratic programming. This paper proposes a new additional force to reduce the cell overlap and to get a uniform distribution of cells. The additional force is not concerned with interconnections between cells, but it is determined by the density of a placement area. In this paper, we modelled that the new additional force is a force which is caused by the dummy fixed cell. And it is used for the global placement. Proposed placement method is compared with TimberWolf v7.0 and Itools vl.4. Proposed placer achieved 7.5% average reduction in wirelength in non timing driven mode, 5.0% average reduction in wlrelength in timing driven mode compared to TimberWolf v7.0. And we got a comparable result to Itools vl.4.

• Proceedings of the Korean Information Science Society Conference
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• 1998.10c
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• pp.600-602
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• 1998

본 논문은 정면과 측면 얼굴 이미지의 특성을 살린 3차원 개인 아바타 합성에 관한 연구이다. 표준 얼굴 메쉬를 얼굴 이미지의 특징점에 맞추려는 힘을 특징점 이외의 점들까지의 거리에 대한 가우스 분포를 따라 부드럽게 전달시켜 매쉬를 탄성있게 변형하는 힘으로 작용시켜 메쉬를 얼굴 이미지의 윤곽선을 중심으로 매칭시키고, 매칭된 메쉬가 매칭 이전의 메쉬의 기하학적 특성을 유지할 수 있도록 메쉬에 동적 피부 모델을 적용한다. 이렇게 생성한 3차원 메쉬에 이미지를 텍스춰 매핑하여 개인 특성을 살린 3차원 개인 아바타를 생성한다.

• The Journal of the Acoustical Society of Korea
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• v.29 no.6
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• pp.355-364
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• 2010

Considering biological safety, it is very important to measure acoustic power from ultrasonic array probe for diagnostic ultrasound imaging applications. In this paper, to measure acoustic power from each element on array probe for ultrasonic diagnostic equipment, we reconstruct and automate the acoustic power measurement system. The acoustic power from linear, phased and curved array were measured and analyzed. As a result of measurement, the effects caused by directivity of sound beam from curved array were founded. To remove these effects, we developed and applied the correction model. The proposed system is useful to evaluate characteristics of the acoustical output power of array probe.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.21 no.3
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• pp.477-484
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• 1997

This paper describes the build-up force measuring system of 9.9 MN capacity which consists of nine force transducers of each having 1.1 MN capacity. We have specially designed a force transducer for a build-up force measuring system to reduce the uncertainty of a build-up system and to accomodate the new test procedure for a build-up system. It reveals that the relative uncertainty of the force measuring system is less than 1.5*10$^{-4}$ in the ran9e of 1-4.5 MN irrespective of loading direction. The force measuring system may be used to calibrate a 10 MN force standard machine to be used as a large force standard in Korea.

• Transactions of the Korean Society of Mechanical Engineers
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• v.19 no.9
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• pp.2194-2205
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• 1995

In order to reduce the systematic error of a build-up system, we have proposed a new test procedure in which all force transducers in a build-up system are rotated by 90.deg. with a base platen fixed on a force standard machine. The setting positions of force transducers on the output of a build-up system were investigated using an orthogonal array. The effects of the parallelism of a build-up system and of the bending moment sensitivity of a force transducer were considered. The experimental results show that the setting position of the base platen hardly affects the output of the build-up system, but the setting positions of force transducers affects it strongly. It reveals that the new test procedure reduces effectively the systematic error of a build-up system.