• 한국세라믹학회지
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• 제48권1호
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• pp.99-105
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• 2011

Lead titanate ($PbTiO_3$) powder was prepared from lead nitrate ($Pb(NO_3)_2$) and titania ($TiO_2$) by hydrothermal route. Phase formation process was investigated by observing the phases formed in various experimental conditions like different KOH concentration, reaction temperature and time. $PbTiO_3$ powder was fabricated when the KOH concentration was 0.8M or higher. An intermediate compound, $PbTi_{0.8}O_{2.6}$, was formed at first by a reaction between PbO and $TiO_2$ and changed into $PbTiO_3$ powder with a perovskite crystal structure. A $PbTiO_3$ phase was formed in a shorter time when a KOH concentration was increased from 0.8M to 8M because a driving force for a $PbTiO_3$ formation was increased due to an increase in a degree of supersaturation. And $TiO_2$ (rutile) and $3PbO{\cdot}H_2O$ were observed at room temperature in a 0.8M KOH solution and $TiO_2$(rutile) and PbO (litharge) in a 8M KOH. A $PbTiO_3$phase was also formed in a shorter time at a higher reaction temperature as a reaction temperature influenced the rates for a dissolution and a precipitation.

• 한국진공학회지
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• 제17권2호
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• pp.96-101
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• 2008

MgO는 플라즈마 디스플레이 패널 (Plasma Display Panel, PDP)의 보호막으로 널리 쓰이고 있다. 기존의 산소 이온빔 보조 증착(Ion-Beam-Assisted Deposition, IBAD) 방법을 이용하여 MgO 보호막을 형성시킨 경우 이온빔의 충전에 의해 야기되는 아크(Arc) 문제 등이 있었다. 이 문제점을 해결하기 위하여, 산소 중성빔 보조증착(Neutral-Beam-Assisted Deposition, NBAD) 방법을 이용하여 MgO를 증착하였다. 그리고 산소 중성빔의 에너지를 변화시킴에 따라 MgO 보호막의 특성과 PDP 패널 방전 특성에 미치는 영향을 분석하였다. 이에 따른 실험 결과로부터 산소 중성빔 에너지가 300eV일 때, 최소 방전 개시 전압, 최고 발광 휘도 및 최고 발광 효율을 얻을 수 있었다.

• 폴리머
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• 제35권4호
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• pp.370-374
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• 2011

폴리아닐린(polyaniline, PANI) 전도성 고분자 용액을 camphorsulfonic acid(CSA)로 도핑하여 제조하였고 FTIR을 이용하여 고분자 중합 및 도핑유무를 확인하였다. 제조된 폴리아닐린을 스핀 코팅하여 유기박막 트랜지스터의 게이트 전극으로 사용하였으며, 열처리 온도변화에 따른 전기 전도도 변화를 4-probe measurement로 확인하였다. 또한 표면 특성을 이해하기 위해 atomic force microscope(AFM)와 optical microscope를 이용하였다. 폴리아닐린 게이트전극을 활용하여 얻은 유기박막 트랜지스터의 소자성능은 최고 이동도가 0.15 $cm^2$/Vs, 전류점멸비가 $2.4{\times}10^6$임을 확인하였다. 고분자 전극의 소지특성을 비교분석하기 위해, 같은 구조의 Au 전극소자를 제작하였다. Au 금속전극소자와 유사한 성능을 보인 폴리아닐렌 게이트 전극 소자는 플렉서블 유기박막 트랜지스터 전극으로 충분히 사용될 수 있다.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2003년도 춘계전력전자학술대회 논문집(1)
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• pp.410-414
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• 2003

In this paper, the virtual-reality system is tried to developed, which controls not only the sense of sight and hearing but also the sense of touch, In order to develope the sense of touch in this study, the stable tactual transaction-system, based on summing up the basic algorithm and theory, is embodied. The hardware of this system consists of the 6DOF haptic interface, a controller and a driver In the case of the software, the proxy algorithm is applied for the force-transaction and the mopping algorithm is used for graphic transaction. In addition to this, the imaginary-device driver is utilized for controlling the system and manager-class is also included in this system to manage the position-change and the like. Consequently, the proxy algorithm Is applied, which makes the system possible to be more stable and prompt with and imaginary object. Moreover, the impulse-algorithm is applied to work out a problem which the tactual transaction-period is different from the graphic transaction-period.

• The Journal of Korean Physical Therapy
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• 제15권2호
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• pp.85-99
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• 2003

Muscle tone is the force with which a muscle resists being lengthened. Muscle tone is often tested clinically by passively extending and flexing a relaxed patient's limbs and feeling the resistance offered by the muscle. Both nonneural and neural mechanism contribute to muscle tone. Muscle tone is the mechanisms that contribute to the generation of tone in individual muscles when a person is in a relaxed state. This background level of activity changes in a certain antigravity posture muscle when we stand upright, thus counteracting the force of gravity. This increased level of activity in antigravity muscles is known as postural tone. The evidence from experiments showing that lesions of the dorsal(sensory) roots of the spinal cord reduced muscle(postural) tone is influenced by inputs from the somatosensory system. Patients with neurological damage have several state of muscle(postural) tone, which display from flaccidity to rigidity. This review article deal with muscle tone and somatosensory system acting on this. The understanding about this contribute to a better therapeutic approach for the rehabilitation of patients to have an abnormal muscle(postural) tone due to neurological damage.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.2440-2443
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• 2005

We propose a new early rehabilitation training system for postural control using a tilting bed and a force plate. The conventional rehabilitation systems for postural control cannot be applied to the patients lying in bed because the rehabilitation training using those systems is possible only when the patient can stand up by himself or herself. Moreover, there has not existed any device that could provide the sense of balance or the sensation of walking to the patients in bed. By using a tilting bed, a visual display, and a force plate, we have developed a new rehabilitation training system for balance control of the patients in bed providing sense of balance and the sensation of walking to the patient. Through the experiments with real people, we verified the effectiveness of the new early rehabilitation training system. The results showed that this system is an effective system for the early rehabilitation training and that our system might be useful as clinical equipment.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2000년도 춘계학술대회 논문집
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• pp.952-955
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• 2000

Nowadays, Internet is so popular that we can easily access the remote site to search information and to communicate remote site and users. People who want to make a collaborate working environment can use JAVA, CORBA, and other internet programming tools like a Perl/XML. The mechanist are try to make the environment fur collaboration within design/manufacturing, simulation, remote sensing through TCP/IP And many industries and research institutions are working towards the agile manufacturing. This paper describes an internet-based real-Time remote monitoring system. The system consists of a hardware setup and a software interface. The hardware setup consists of a machine and its data acquisition hardware, while the software interface incorporates the data acquisition software, the server program, and the client program. The server program acts as the main interface between the data acquisition system and the internet technology. The client program is to be distributed to the remote users who want to monitor the machining status. The system has been demonstrated and verified for an industrial High-Speed Machine (HSM) especially measuring cutting force and acoustic emission. To share the signal, we make the WWW server and display its value. The system has been found to be highly efficient, reliable and accurate.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1996년도 하계학술대회 논문집 C
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• pp.1572-1575
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• 1996

A new type $Cu_{x}N/Cu/Cu_{x}N$ thin film electrode material with high adhesion to glass was developed by the dc reactive planar magnetron sputtering system for the PDP(Plasma Display Panel). The adhesive force of the $Cu_{x}N$ thin film was in the range of $20{\sim}40(N)$ under the conditions of the $N_2$ partial pressure of 15%, discharge current of 70mA, discharge voltage of 450V and substrate bias voltage of -100V. The adhesive force was depended on the $N_2$ partial pressure, discharge current and substrate bias voltage.

• 한국생산제조학회지
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• 제19권4호
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• pp.553-561
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• 2010

In flat panel display or semiconductor industries, they install the equipments with fine line width and high throughput for fabrication and inspection. The equipments are required to have the linear stage which can position the work-piece with high speed, fine resolution on wide range of motion. In this paper, a precision planar linear XY stage is proposed. The stage has a symmetric planar window configuration and is guided by air-bearings on granite plate. The symmetric planar window configuration makes the stage has robustness against dynamic and thermal disturbances. The air-bearings let the stage move smooth on straight guide bar and flat granite surface. The stage is actuated by linear motor with Halbach magnet array (HMA). HMA generates more confined magnetic flux than conventional array. The linear motors are optimized by using sequential quadratic programming (SQP) with the several constraints that are thermal dissipation, required power, force ripple and so on. The planar linear XY stage with the symmetric planar configuration and the linear motors is implemented and then the performance such as force ripple, resolution and stroke are evaluated.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2004년도 추계 학술발표회 제16권2호
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• pp.781-784
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• 2004

Method of Steel plate reinforced by fiber sheet is advantageous in the secure loading facility. For this method are a light weight and a high strength, the thickness of steel can be reduced Effects of composite system are depreciated when the thickness of steel is thin. This is the result of the difference of ductility ratio with steel plate. Steel plate reinforced by fiber sheets confirms the ability of transformation. This is the result of the property of steel materials Steel plate reinforced by fiber sheet didn't display an enough performance when theadhesives are epoxy rosin. This is the result of the slide of the surface of stee1. The adhesive ability is varied by the number and span of anchor bolts. There wasn't happening the separation between steel and epoxy. Thus the method used in combination with anchor and epoxy is best excellent. This is the result of the upward of accumulation effects Shearing force is in proportion to the number of bolts. But the ability of shearing force per one bolt is reducing. Thickness of steel plate reinforced by fiber sheet must be designed so that steel is endure before concrete is wreck.