• 한국강구조학회 논문집
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• 제23권6호
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• pp.715-724
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• 2011

인장구조 시스템에서 구조물의 하중을 지지하는 인장재 사이에 삽입되어 인장력을 조절하는 장치가 턴버클이다. 인장재가 인장구조에서 중요한 부재임에도 불구하고, 현재 인장재에 발생하는 인장력을 경제적이고 간단하게 측정하기 위한 방법이 제안되지 못하였다. 그리하여 인장구조시스템에 작용하는 인장력을 측정하기 위하여 인장력 측정장치를 개발하였다. 본 논문에서는 이론해석과 유한요소해석을 바탕으로 100kN, 200kN, 300kN급 측정한계하중을 가지는 턴버클을 실험하였다. 그 결과 이론적 해석, 유한요소해석, 실험결과는 대체로 일치하는 것으로 나타났다. 또한 유한요소해석에 의한 측정용 턴버클의 극한강도를 조사해보면, 측정한계하중의 5배 이상의 과하중에서도 충분한 안전성을 확보하고 있음을 확인할 수 있었다.

• 한국전기전자재료학회논문지
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• 제19권7호
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• pp.631-635
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• 2006

The properties of metal interlayered DLC films between the Si substrate and the DLC films were studied. DC magnetron sputtering method has been used to deposit intermediate layers of metals. And RF-PECVD method has been employed to synthesize DLC onto substrates of the silicon and metal layers. After we used metal Inter-layers, such as chromium, nickel, titanium and we studied tribological properties of the DLC films. The thickness of films were observed by field emission scanning electron microscope (FE-SEM). Also the surface morphology of the films were observed by an atomic force microscope (AFM). The crystallographic properties of the films were analyzed with X-ray diffraction (XRD), the friction coefficients were investigated by AFM in friction force microscope (FFM) mode. Tribological performances of the films were estimated by nano-indenter, stress tester measurement.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 합동 추계학술대회 논문집 정보 및 제어부문
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• pp.260-263
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• 2001

This paper is to develop the sensing system for opening-force measurement such as O-Ring muscular meridian. We designed to overcome the functional limit that the conventional force-sensor can measure just the closing-force. Therefore, the new sensor can meet a variety of application as well as O-Ring test. The structure of the new sensor is an actuator-type system using an electromagnet. That is made up of mechanical system, electromagnet, current transformer and computer interface circuit. Driving software and user interface program of the new sensor system also is explained in this paper.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 하계학술대회 논문집 Vol.4 No.2
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• pp.791-794
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• 2003

DLC thin films were prepared by microwave plasma-enhanced chemical vapor deposition method on silicon substrates using methane ($CH_4$) and hydrogen ($H_2$) gas mixture. The negative DC bias ($-450V{\sim}-550V$) was applied to enhance the adhesion between the film and the substrate. The films were characterized by Raman spectrometer. The surface morphology was observed by an atomic force microscope (AFM). And also, the friction coefficients were investigated by AFM in friction force microscope (FFM) mode, which were compared with the pin-on-disc (POD) measurement.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 하계학술대회 논문집 Vol.4 No.2
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• pp.842-845
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• 2003

DLC thin films were prepared by microwave plasma-enhanced chemical vapor deposition method on silicon substrates using methane ($CH_4$) and hydrogen ($H_2$) gas mixture. The negative DC bias ($-450V{\sim}-550V$) was applied to enhance the adhesion between the film and the substrate. The films were characterized by Raman spectrometer. The surface morphology was observed by an atomic force microscope (AFM). And also, the friction coefficients were investigated by AFM in friction force microscope (FFM) mode, which were compared with the pin-on-disc (POD) measurement.

• 대한기계학회논문집
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• 제18권6호
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• pp.1510-1519
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• 1994

It is important to understand the friction characteristics between piston-ring assembly and cylinder wall for the friction loss reduction as well as the solution of problem such as scuffing wear and oil consumption. A new system was developed for the piston-ring assembly friction force measurement. This system was applied to the friction force measurement to find its functional relationship with variables such as engine speed, oil viscosity, and engine load. The friction mean effective pressure(fmep) was found to have a linear relationship with$(\vpsilon{U})^{0.42}$ under motering and with$(\vpsilon{U})^{0.45}$ under firing operations, where $\vpsilon$ is the kinematic oil viscosity and U is mean piston speed.

• 센서학회지
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• 제20권6호
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• pp.393-399
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• 2011

In this paper, we designed and fabricated the novel air flow sensor using air drag force, which can be applied to the low air flow detection. To measure the low air flow, we should enlarge the air drag force and the output signal at the given air flow. The paddle structure is applied to the device, and the device is vertically located against the air flow to magnify the air drag force. We also adapt the corrugation structure to improve the output signals on the given air velocity. The device structure is made up of the silicon nitride layer and the output signal is measured with the piezoresistive layer. The output signals from the corrugated device show the better measurement sensitivity and the response time than that of flat one. The repeated measurement also shows the stabilized signals.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2002년도 추계학술대회 논문집(II)
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• pp.898-903
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• 2002

The railroad is a means of large transportation which has many talents such as a safety and a regularity. That is a results from various confidential performance tests and evaluations of the system. The railroad system consist of various subsystems - vehicle, power supply, signal, communications, track structures, operations, etc. Among them, as an item of safety evaluation there is a measurement of wheel/rail force, so called a measurement of derailment coefficient. This is a very important item because a derailment of a train will bring about a big accident. Especially it is more inportant in high speed rail of which operation speed is over two times as fast as existing rail. In this paper, it is introduced to preprocess the wheelset for measuring wheel/rail force of high speed rail, such as to treat a measuring wheelset, its finite element analysis, adhesion of strain gauges and static load test.

• Fibers and Polymers
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• 제4권3호
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• pp.129-134
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• 2003

We have shown in Part I [1] of this study that medical needle-stick injuries are causing serious health problems to healthcare personnel and other professionals that require the attention of healthcare and textile researchers to develop new protective systems. Responding to such need, a needle force measurement device that is capable of measuring dynamic forces experienced by medical needles during needle penetration through protective articles was developed and described in part I. This paper reports the results of evaluation of protective woven fabrics from high performance fibers and standard and bifid medical needles using the force measurement system. The woven fabrics varied in cover factor, number of layers, and orientation angle. Standard and bifid needles with different gap widths were used to evaluate the resistance of the fabric to needle penetration.

• 한국기계가공학회지
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• 제7권1호
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• pp.3-8
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• 2008

This paper reports some experimental results of cylindrical external grinding using CBN wheels. Many experimental studies for surface grinding have been done, but not for the cylindrical grinding due to the difficulty of grinding force measurement. In this paper a new experimental device has been proposed for the grinding force measurement in cylindrical grinding. The cylindrical grinding experiments were carried out at various grinding conditions with several CBN grinding wheels. The experimental results indicate that the CBN wheels with smaller grains result in the higher grinding forces in both SCM415 and STD11 workpieces. The grinding forces of all wheels were proportional to the infeed speeds and the difference of each wheels was prominent at high infeed speed for SCM415.