인터넷기반의 원격 계측 실험실 구축에 관한 연구

곽문규,정경권,신재호,Kwak Moon-K.,Chung Kyung-Kwon,Shin Jae-Ho 한국공학교육학회 2000 공학교육연구 Vol.3 No.2

This paper is concerned with the development of remote engineering laboratory using the internet. Recently, various virtual laboratories are introduced using the multimedia technologies but the internet laboratory using the real hardware system is not present. In this study, we developed the remote engineering laboratory by combining the GPIB program which controls the hardwares with the web programming which controls the internet. The function generator, LCR meter, and oscilloscope were considered as the measurement devices. The client program includes the user-interface which carry out experiment remotely. Several electrical experiments were set up to verify the experimental process. It has been found that the remote engineering experiments are feasible and valid. The methodologies will be discussed in detail. 본 논문은 인터넷을 이용한 공학 교육의 효과를 높이기 위한 수단으로서 원격 계측 실험실의 구축에 대하여 연구한 결과를 포함하고 있다. 최근에 멀티미디어를 이용한 가상 실험 실습실의 축이 가시화되고 있으나 실제 시스템을 대상으로 한 인터넷 실험 실습실은 널리 보급되고 있지 않다. 본 논문에서는 실험실 자동화를 위하여 사용된 GPIB제어 기술과 인터넷 연결 기술을 결합하여 원격으로 실험 실습이 가능한 시스템을 구축하였다. 함수발생기, LCR미터, 오실로스코우프에 대한 제어 프로그램을 구축하고 몇 가지 전자 회로를 대상으로 실험을 수행해 본 결과 다양한 종류의 실험을 원격으로 수행할 수 있으며 교육 효과 또한 매우 높음을 발견할 수 있었다. 본 연구에서는 원격 계측 실험실 구축과 관련된 기술을 소개하고 문제점을 토의하고자 한다.

자동차 클러치 Judder 및 Shunt 현상에 대한 해석

곽문규,이영민 동국대학교 산업기술환경대학원 1996 산업기술논총 Vol.3 No.-

This paper is concerned with the dynamic analysis of an auto power train vibration problem. In particular, the clutch judder and shunt phenomena caused by the dynamic friction of the clutch pad are analyzed by means of the mathematical model. This paper presents the effect of parameters on the vibration characteristics of the system, thus illustrating the method of avoiding the harsh start-up problem. Numerical results show that the clutch judder and shunt can be avoided by increasing the system damping value either globally or locally. In addition, the friction coefficient affects the stability of the system thus causing instability to some modes. However, the main source of excessive vibration is resulted from the excitation force which depends on the friction coefficient.

보의 회전 및 진동제어를 위한 동적 모델 타당성 연구

곽문규,남상현 한국소음진동공학회 2001 소음 진동 Vol.11 No.2

This research is concerned with the validation of the modeling technique and controller design for slewing beam structures. When cantilever beam rotates about axes perpendicular to the undeformed beam's longitudinal axis, it experiences inertial loading. Hence, the beam vibrates from the initial stage of slewing. In this paper, the analytical model for a single slewing flexible beam with surface bonded piezoelectric sensor and actuator is developed using the Hamilton's principle with discretization by the assumed mode method. Comparisons with the theoretical model are made based upon the frequency responses and time responses. A new factor called the coupling coefficient is introduced to incorporate the discrepancies between the theoretical and experimental results. The slewing is achieved by applying the PID control, which is found to be less sensitive to vibrations. The vibrations are controlled by PPF controller, which is found to be effective in suppressing residual vibrations after slewing. The vibrations occurred during slewing is difficult to control because the piezoceramic actuator is not powerful enough to overcome inertial loadings.

PPF와 SRF 조합기법을 사용한 지능구조물의 능동진동제어

곽문규,라완규,윤광준 한국소음진동공학회 1997 소음 진동 Vol.7 No.5

This paper is concerned with the active vibration controller design for the grid structure based on the positive position feedback (PPF) and the strain rate feedback (SRF) control. A new control methodology by the combination of the PPF and SRF control can suppress all the modes of the structure theoretically and can be easily implemented with analog circuits. The underlying concept for the design of the new controller is that the SRF controller stabilizes the modes higher than the second mode and the PPF controller stabilizes the fundamental mode which is destabilized by the SRF controller. In order for the new controller to be implemented succesfully, the collocated control is necessary. To this end, the piezoceramic sensor and actuator are located as close as possible, thus realizing the nearly collocated control. The combined PPF and ARF controller proves its effectiveness by experiments.

지능구조물의 능동진동제어를 위한 다중 PPF 제어기와 수정 LQG 제어기의 비교 연구

곽문규 한국소음진동공학회 1998 소음 진동 Vol.8 No.6

This research is concerned with the multiple PPF and the modified LQG controller design for active vibration control of intelligent structures. The intelligent structure is defined as the structure equipped with smart actuators and sensors. Various control techniques aimed for the piezoceramic sensors and actuators have been proposed for the active vibration control of smart structures and some of them prove their effectiveness experimentally. In this paper, the multiple PPF controller and the modified LQG controller are developed and applied to the smart grid structure. The multiple PPF control and the modified LQG control can be classified as the classical and the modern control techniques. respectively. The experimental results show that both control techniques are effective in suppressing vibrations. Two control techniques are compared with respect to the design process. the ease of implementation and the effectiveness

인터넷을 이용한 원격 계측 및 제어 기술

곽문규 한국소음진동공학회 2002 소음 진동 Vol.12 No.3

능동 촉각 기술과 웨이브

곽문규 한국소음진동공학회 2015 소음 진동 Vol.25 No.2

엔지니어의 변신

곽문규 한국소음진동공학회 2008 소음 진동 Vol.18 No.3

전동식 능동형 엔진 마운팅 시스템

곽문규 한국소음진동공학회 2009 소음 진동 Vol.19 No.3

Isorhamnetin의 근육세포 미토콘드리아 기능조절에 미치는 효과

이막순(Mak-Soon Lee),김양하(Yangha Kim) 한국영양학회 2021 Journal of Nutrition and Health Vol.54 No.4

Purpose: Muscle mitochondria play a key role in regulating fatty acid and glucose metabolism. Dysfunction of muscle mitochondria is associated with metabolic diseases such as obesity and type 2 diabetes. Isorhamnetin (ISOR), also known as 3-O-methylquercetin, a quercetin metabolite, is a naturally occurring flavonoid in many plants. This study evaluated the effects of ISOR on the regulation of the mitochondrial function of C2C12 muscle cells. Methods: C2C12 muscle cells were differentiated for 5 days, and then treated in various concentrations of ISOR. Cytotoxicity was determined by assessing cell viability using the water-soluble tetrazolium salt-8 assay principle at different concentrations of ISOR and time points. Levels of the mitochondrial DNA (mtDNA) content and gene expression were measured by quantitative real-time polymerase chain reaction. The citrate synthase (CS) activity was quantified by the enzymatic method. Results: ISOR at a concentration of 10 μM did not show any cytotoxic effects. ISOR increased the mtDNA copy number in a time- or dose-dependent manner. The messenger RNA levels of genes involved in mitochondrial function, such as peroxisome proliferator-activated receptor-γ coactivator-1α, and uncoupling protein 3 were significantly stimulated by the ISOR treatment. The CS activity was also significantly increased in a time- or dose-dependent manner. Conclusion: These results suggest that ISOR enhances the regulation of mitochondrial function, which was at least partially mediated via the stimulation of the mtDNA replication, mitochondrial gene expression, and CS activity in C2C12 muscle cells. Therefore, ISOR may be useful as a potential food ingredient to prevent metabolic diseases-associated muscle mitochondrial dysfunction.