• 센서학회지
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• 제13권3호
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• pp.218-223
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• 2004

Thin film gas sensor based on tin oxide was fabricated and its characteristics were examined. Target gas is acetonitrile ($CH_{3}CN$) that is simulant gas of blood agent gas. Sensing materials are $SnO_{2}$, $SnO_{2}$/Pt, and (Sn/Pt)oxidation with thickness from $1000{\AA}$ to $3000{\AA}$. Sensor was consisted of sensing electrode with interdigit (IDT) type in front side and a heater in back side. Its dimension was $7{\times}10{\times}0.6mm^{3}$. Fabricated sensor was measured as flow type and monitored real time using PC. The optimal sensing material for $CH_{3}CN$ was {Sn($3000{\AA}$)/Pt($30{\AA}$)}oxidation and its sensitivity and operating temperature were 30%, $300^{\circ}C$ in $CH_{3}CN$ 3 ppm.

• Journal of Acupuncture Research
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• 제32권1호
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• pp.23-36
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• 2015

Objectives : This study was designed to investigate the neuroprotective effects of Hominis-Placenta (HP)on dopaminergic neurons. Methods : We examined the effect of invitro administration of HP against 1-methyl-4-phenylpyridinium( MPP+)-induced dopaminergic cell loss in primary mesencephalic culture and also used behavioral tests and performed analysis in the striatum and the substantia nigra of mouse brain, to confirm the effect of HP on dopaminergic neurons in an invivo 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine(MPTP)-induced PD mouse model. Animals were assigned to four groups: (1) Group 1(vehicle-treatedgroup), (2) Group 2(MPTPonlytreated group), (3) Group 3(MPTP+ saline-treated/$ST_{36}$ group), and (4) Group 4(MPTP+HP-treated/$ST_{36}$ group). HP at $20{\mu}L$ of 48 mg/kg dose was injected at $ST_{36}$ for 4 weeks at 2-day intervals. MPTP in saline was injected intraperitoneally each day for 5 days from the $8_{th}$ treatment of HP. We performed the pole test and rota-rod test on the first and seventh day after the last MPTP injection. To investigate the effect of HP on dopaminergic neurons, we performed analysis in the striatum and the substantia nigra of mouse brain after treatment with HP and/or MPTP. Results : Treatment with HP had no influence on cell proliferation and caused no cell toxicity in $PC_{12}$ and $HT_{22}$ cells. Our study showed that HP significantly prevented cell loss and protected neurites against MPP+ toxicity. Although the invivo treatment of HP herbal acupuncture at $ST_{36}$ showed a tendency to improve movement ability and protected dopaminergic cells and fibers in the substantia nigra and the striatum, it did not show significant changes compared with the MPTP treated group. Conclusions : These data suggest that HP could be a potential treatment strategy in neurodegenerative diseases such as Parkinson's disease.

• Molecules and Cells
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• 제41권2호
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• pp.140-149
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• 2018

The $TIS21^{/BTG2/PC3}$ gene belongs to the antiproliferative gene (APRO) family and exhibits tumor suppressive activity. However, here we report that TIS21 controls lipid metabolism, rather than cell proliferation, under fasting condition. Using microarray analysis, whole gene expression changes were investigated in liver of TIS21 knockout (TIS21-KO) mice after 20 h fasting and compared with wild type (WT). Peroxisome proliferator-activated receptor alpha ($PPAR{\alpha}$) target gene expression was almost absent in contrast to increased lipid synthesis in the TIS21-KO mice compared to WT mice. Immunohistochemistry with hematoxylin and eosin staining revealed that lipid deposition was focal in the TIS21-KO liver as opposed to the diffuse and homogeneous pattern in the WT liver after 24 h starvation. In addition, cathepsin E expression was over 10 times higher in the TIS21-KO liver than that in the WT, as opposed to the significant reduction of thioltransferase in both adult and fetal livers. At present, we cannot account for the role of cathepsin E. However, downregulation of glutaredoxin 2 thioltransferase expression might affect hypoxic damage in the TIS21-KO liver. We suggest that the $TIS21^{/BTG2}$ gene might be essential to maintain energy metabolism and reducing power in the liver under fasting condition.

• 한국통신학회논문지
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• 제35권1C호
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• pp.24-32
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• 2010

본 논문에서는 버려지거나 없어진 객체를 검출하는 시스템에 대해 연구하였다. 전경과 배경을 분리한 다음, 정적인 영역에 대한 검출을 통하여 방치되거나 제거된 물체를 검출하였다. 정적인 영역에 대한 검출 방법을 제안하고 히스토그램의 비교를 통해 방치, 제거 정보를 추출하였다. 제안된 방법은 CCTV 카메라의 입력 영상에 대하여 PC 및 DSP 칩을 이용하여 실시간 처리를 하였으며 DSP칩을 활용하였기 때문에 수정이 용이하다. 제안된 시스템에 대한 성능을 검증하기 위해 저, 중, 고의 복잡도에 따라 실험하였으며, 신뢰성 있는 검증을 위해 각 10회의 반복 수행을 하였다. 실험 결과, 복잡도가 낮거나 보통인 경우는 높은 객체 변화 검출률을 보였으며 매우 혼잡한 경우에는 환경적인 요인의 이유로 검출률이 상대적으로 낮은 것을 확인할 수 있었다. 이 원인은 복잡도가 높아짐에 따라 검출률이 낮은 것은 이동하는 객체들로 인해 방치된 객체의 폐색이 반복되기 때문이었다. 향후 이러한 문제의 해결을 위해 매우 복잡한 환경에서의 폐색에 대한 추가적인 연구와 강건한 정적 영역의 판단 방법에 대해 연구할 것이다.

• 한국해양공학회지
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• 제11권3호
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• pp.56-68
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• 1997

This work was intended to study the effect of a partial pressure ratio and a total pressure of reactive gases on the properties of TiC$_{x}$N$_{1-x}$ . coated layer. In this regard, various TiC$_{x}$N$_{1-x}$ coatings were synthesized with C2112 and N2 Mixture gas of different compositions by Arc Ion Plating process which has been highlighted for an industrial purpose. It was revealed from colors and X-ray diffraction patterns that the concentration of carbon of a TiC$_{x}$N$_{1-x}$ coating increases with a partial pressure ratio (PC$_{2}$H$_{2}$/PN$_{2}$) as well as a total pressure Of $C_{2}$H$_{2}$ and N$_{2}$ mixture gas. Accordingly, the hardness of TiC$_{x}$N$_{1-x}$ coated layer increased but the adhesion to the substrate of SKH 51 was degraded. On the other hand, the deposition rate was independent of a partial pressure ratio and a total pressure of mixture gas. It was found that a uniform gas distribution is critical for an industrial application since the composition of a coating depends strongly on the location of a substrate inside of the furnace. As a result of milling tests with different TiC$_{x}$N$_{1-x}$ coated end mills, the one which has a low carbon concentration was better than others studied in this work.d in this work.

• 전기학회논문지
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• 제60권7호
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• pp.1417-1426
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• 2011

Radiofrequency ablation through cardiac catheterization is one of minimally invasive intervention procedures used in drug resistant arrhythmia treatment. To facilitate more accurate and precise catheter navigation, systems for robotic cardiac catheter navigation have been developed and commercialized. The authors have been developing a novel robotic catheter navigation system. The system is a network-based master-slave configuration 3-DOF (Degree-Of-Freedom) robotic manipulator for operation with conventional cardiac ablation catheter. The catheter manipulation motion is composed of the translation (forward/backward) and the roll movements of the catheter and knob rotation for the catheter tip articulation. The master manipulator comprises an operator handle compartment for the knob and the roll movement input, and a base platform for the translation movement input. The slave manipulator implements a robotic catheter platform in which conventional cardiac catheter is mounted and the 3-DOF motions of the catheter are controlled. The system software that runs on a realtime OS based PC, implements the master-slave motion synchronization control in the robot system. The master-slave motion synchronization performance tested with step, sinusoidal and arbitrarily varying motion commands showed satisfactory results with acceptable level of steady state error. The developed system will be further improved through evaluation of safety and performance in in vitro and in vivo tests.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 학술대회 논문집 전문대학교육위원
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• pp.187-190
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• 2002

In contrast to conventional electromagnetic motor, USM(Ultrasonic Motor), as piezoelectric ceramic applying ultrasonic mechanical vibration and as frictional-movement type motor, get rotational torque by elastic friction between stator and rotator, The USM, which is small motor without iron cores and coil as a simple structure, has little load weight, has character of high torque at low speed, and can apply a direct drive type without deceleration gear as low speed type. A response of USM from control input is satisfactory, and also generates much torque in low speed driving, and holding torque is much without supplying power. In this study, I designed and made Ultrasonic motor-digital multi controller(USM- DMC) using FPGA chip, A54SX72A made in Actel Corporation. By the minute, USM-DMC can control frequency, duty ratio, and phase difference of USM by llbit digital input from Pc. Therefore, when we use this controller, we can apply to typical parameter, frequency, phase difference, and voltage parameter, to control as well as we can do mixing control like phase-frequency, phase-voltage, frequency-voltage, frequency-phase-voltage, What is more, the strongest point is that it can trace frequency based on optimized frequency because we can input optimized resonant frequency while in motoring.

• 한국정보처리학회논문지
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• 제6권9호
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• pp.2540-2547
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• 1999

크로마키 합성이란 텔레비전 방송국 또는 일반 스튜디오에서 사용되는 영상처리 기술로써, 블루스크린을 배경으로 하는 스튜디오에서 촬영된 영상의 파란부분을 컴퓨터 그래픽 또는 실영상으로 교체하여 합성하는 기술이다. 특히, 가상 스튜디오의 크로마키 합성은 배경영상을 카메라의 움직임에 연동하여 변화시킴으로써 기존 스튜디오보다 자연스러운 합성을 수행할 수 있다. 본 논문에서는 카메라의 움직임에 연동하여 블루스크린에 그려진 오각형패턴의 변화만을 인식하여 역으로 카메라 파라메터를 추출하는 방법을 제안하였다. 일반적으로 오각형패턴은 카메라의 움직임 즉 투영변환에 불변하는 특징을 가지고 있으므로 이를 이용하여 스크린 위의 오각형패턴과 촬영된 영상 위의 대응패턴을 용이하게 구할 수 있다. 그리고, 구해진 대응패턴과 대응점을 이용하여 평면의 투영 변환식을 구하고 이를 변형된 Tsai의 방법을 사용하여 카메라 파라메터를 추출한다. 실험 결과를 통하여 제안된 방법이 원래의 Tsai의 방법보다 정확한 카메라 파라메터를 구할 수 있었으며 Pentium-MMX PC에서 초당 12 프레임의 카메라 파라메터를 추출할 수 있었다.

• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1993년도 추계학술대회
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• pp.40-43
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• 1993

Electronic fetal monitoring system is an easier ar d usual method in various prenatal and labor period fetal surveilence methods currently in use. But there haven't been enough cases of using the central monitoring system despite the fact that the bedside fetal monitoring system have already been widely in use in Korea as an essential medical equipment item. We have developed more efficient central fetal monitoring system based on the personal computer with the visual maternal monotoring device using infrared camera which processes the signals from existing bedside fetal monitoring systems such as H/P's 8040 series. And we have performed the clinical application on 41 pregnant women and the results were satisfactory. In conclusion, more efficient and familial fetal monitoring is possible with our PC based central fetal monitoring system which provides the medical personnel with the view of a selected pregnant woman on the same screen where the electronic waveforms and data are displayed.

• 한국산학기술학회논문지
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• 제16권9호
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• pp.6282-6289
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• 2015

최근 공인인증서 유출 사고가 급증하고 있으며 이로 인한 전자금융사기가 빈번하게 일어나고 있다. 공인인증서와 개인키는 파일 형태로 존재하여 접근이 용이하고 쉽게 복사가 가능하기 때문에 PC의 하드디스크나 이동식디스크 등에 저장해두는 경우 악성코드에 의한 파밍, 피싱, 스미싱 등의 해킹 공격에 의하여 유출될 위험이 높다. 따라서 안전한 저장매체인 보안토큰, 저장토큰 등을 권고하고 있지만 분실 위험, 비용 문제 등의 이유로 실제로 사용하는 사람은 소수에 불과하다. 본 논문에서는 이러한 문제를 해결하고 단점을 보완하기 위하여 인증서와 개인키를 인증기관에서 보관하도록 하고 사용자는 본인 소유의 단말에서 바이오인증절차를 거쳐 인증기관에게 기기 고유 식별자와 인증토큰을 전달함으로써 인터넷 뱅킹을 위한 본인확인 및 전자서명을 수행할 수 있는 시스템을 제안한다. 제안하는 시스템은 인증서 비밀번호 입력 없이 바이오인증만으로 인증기관을 통하여 전자서명을 수행할 수 있어 기존 시스템에 비하여 서비스 이용이 간편하며 키로깅, 저장매체 분실, 인증서 유출 등의 위협요소를 무력화시킴으로써 안전한 인터넷 뱅킹 환경을 제공한다.