• 한국정밀공학회지
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• 제30권3호
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• pp.331-339
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• 2013

The Interest in disease prevention and rehabilitation is increasing depending on increase of patients with spinal. This is being developed using the spine stabilization device is being studied. So far studies have only evaluated the effect on trunk stabilization exercises but analysis of human movement patterns for active movement and passive movement did not. We assessed the muscle activity of trunk and leg muscle during passive and active tilt mode on eight tilt directions at tilt angle of $30^{\circ}$ using 3-D dynamic postural balance training system. We performed experimental study on the muscular activities of trunk muscle about rectus abdominis, external obliques, latissimus dorsi, erector spinae, and leg muscle about rectus femoris, Biceps femoris, Tibialis Anterior, gastrocnemius. As a result, muscle activation was different depending on the direction of movement and pattern. The results indicate that various patterns of spinal stabilization exercise system could be applied to an effective training of chronic low back pain patients.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 학술회의 논문집 정보 및 제어부문 B
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• pp.823-825
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• 2003

A sensor system was designed to measure real time vibro displacement of civil structure. The He-Ne laser is used for the displacement measuring method, because it guarantees short time stabilization, long time output power stability. Also, it guarantees simple maintenances and repairs under actual using condition. The line CCD image sensor(Tcd-142d) is used to detect the displacement of Ne-Ne laser responding to the vibro of civil structure. For accurate measurement and comparison, CDP-50 is used. Usually CDF-50 (Strain type displacement device) is used for the standard correction device of optical measurement equipments. The data processing part is consists of Optical sensor part, Wireless data transmission device, DAQp-1200, and LapView program. The displacement data of vibro from optical sensor part inputted to wireless data transmission device and then transmitted to DAQp-1200 in main control room. DAQp-1200 performs A/D conversion for the receiving data. After that the converted data inputted to computer system using LapView program for user display. The significance of this paper is to develope a convenient, accurate and lost saving real time displacement measurement system for the civil structure.

• 전기의세계
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• 제19권2호
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• pp.6-11
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• 1970

For the variable speed in automatic control, this paper describes, at first, performance equations of an induction motor which has the free rotating stator. This motor with rotating stator has a speed control factor itself by equivalent variable frequency in stator side. Secondly, an additional invertor source on the rotor slip ring serves the purpose of improving the speed control factor. The advantages decribed above permit to control the speed continuosly from zero to maximum allowable speed with low energy of thyristor a feed-back device may be used for speed stabilization under variable load.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2021년도 추계학술대회
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• pp.590-593
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• 2021

본 연구에서는 목발을 사용하는 교통약자가 물품을 안정적으로 휴대할 수 있도록 도와주는 장치를 개발하였다. 2축 짐벌 구조를 기반으로 서보모터, IMU센서, 아두이노 나노 마이크로프로세서로 구현하였고, Pitch와 Roll 방향 회전을 상쇄하기 위해 센서 각도를 변환 없이 사용하는 기본제어법과 PID 제어법을 사용하여 비교하였다.

• 한국분무공학회지
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• 제20권2호
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• pp.76-81
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• 2015

Swirl flow has an impact on the stabilization of the flame by the recirculation flow, improvement of the combustion efficiency. The swirl flow in the gun type burner is created by the spinner which is inside the airtube that guide the combustion air. Burner has generally the combustion device composed electronic spark plug, injection nozzle, combustion device adaptor, and spinner. These inner components change the air flow behavior passing through airtube. So, this study analyzed exhaust flow characteristics of the gun type burner according to the ratio of airtube diameter. Turbulence characteristics by the spinner was mean velocity, turbulence intensity, kinetic energy, shear stress and flattness factor of the air flow of axial direction and tangential direction from the exit of the airtube.

• 제어로봇시스템학회논문지
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• 제12권3호
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• pp.277-283
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• 2006

A recently proposed method for stabilizing haptic interfaces and teleoperation systems was tested with a 'PHANToM' commercial haptic device. The 'Passivity Observer' (PO) and 'Passivity Control1er' (PC) stabilization method was applied to stabilize the system but also excited a high frequency mode in the device. To solve this problem, we propose a method to use a timevarying desired energy threshold instead of fixed zero energy threshold for the PO, and make the actual energy input follow the timevarying energy threshold. With the time-varying energy threshold, we make the PC control action smooth without sudden impulsive behavior by distributing the dissipation. The proposed new PO/PC approach is applied to PHANToM with high stiffness (K = 5000N/m), and stable and smooth contact is guaranteed. Resetting and active environment display problems also can be solved with the reference energy following idea.

• 전자공학회논문지D
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• 제36D권1호
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• pp.100-106
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• 1999

SOI MOSFET에서 바디 전압을 안정시키기 위하여 바디 저항과 콘택 소모면적을 줄이면서도 SOI 고유의 장점을 그대로 유지시키는 IBC(Island Body Contact) 구조를 창안하였다. 이 구조는 여러 MOSFEET 들의 바디를 서로 연결하여 같이 콘택을 형성함으로써 면적의 증가 없이 훌륭한 바디 콘택효과를 갖게 된다. VLSI 소자로서의 그 가능성을 소자 시뮬레이션과 제작된 소자와 회로의 측정실험을 통하여 확인하였다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회B
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• pp.2977-2983
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• 2008

The combustion characteristics of a partially premixed flame in a dump combustor were studied to determine the effects of hydrogen enrichment in propane. Bluff-body was used for flame stabilization. Fuel mixtures containing a hydrogen mole fraction ranging from 0.1 to 0.5 were burnt at ambient pressure within a quartz chamber. Tests were carried out keeping the total reactant flow rate by adjusting the fuel and air flow rates. The fluctuations of pressure were measured by piezoelectric pressure sensor. The instantaneous flame structure and OH chemiluminescence images were described by High-speed Intensified Charged Coupled Device (HICCD) camera and Intensified Charged Coupled Device (ICCD) camera. The present results show that hydrogen enrichment in fuel changed the location of primary reaction zone from inner recirculation zone to turbulent shear layer and pressure signal. The reason is that chemical aspects take precedence over flow aspects in the hydrogen-enriched flame.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2010년도 춘계학술대회
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• pp.725-727
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• 2010

선박의 운동을 시뮬레이터 하기 위해서는 Pitch, Roll, Yaw의 세가지 선박 운동 요소를 시뮬레이터 할 수 있어야 한다. 이를 위해 선박의 운동을 시뮬레이터 할 수 있는 6축의 자유도를 가지는 모션 시뮬레이터를 설계 개발 하였다. Gyro Sensor based Servo Motion Control 알고리즘은 선박의 6자유도운동을 분석하여 그에 대응 할 수 있는 Motion Control 동요안정화 제어장치를 개발하였다.

• 한국항공우주학회지
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• 제35권5호
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• pp.438-445
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• 2007

액체로켓엔진에서 발생하는 고주파 연소 불안정 제어를 위한 수동 안정화 제어 기구로 음향공을 적용하여, 선형 음향 해석 및 상온 음향 실험을 통해 감쇠 효과의 적합성을 검증하였다. 단일 음향공의 기하학적 형상에 따른 음향 감쇠 효과를 비교하기 위하여 오리피스 직경, 길이를 변화시킨 몇 가지 음향공 모델에 대해 유해 공진주파수 감쇠 효과를 정량적으로 비교, 분석하였다. 다음으로 음향공의 개수에 따른 음향 감쇠 효과를 비교하였다. 주파수 응답함수를 통한 유해주파수 감쇠 성능은 개수 증가에 따라서 우수해졌지만 흡음계수를 통한 최적의 효율 관점에서 볼 때 오히려 과도한 댐핑으로 인한 해당 주파수의 감쇠 효율이 낮아지는 경향이 발생한다. 결론적으로 음향공을 이용한 제어를 위해서는 유해주파수를 감쇠시킬 수 있는 기하학적 형상을 통한 정확한 동조가 필요하다. 또한, 부피의 제약을 고려한 최적의 효율을 발휘할 수 있는 음향공의 형상 설계와 개수의 선택이 절대적으로 필요함을 입증한다.