• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1995년도 추계학술대회 논문집
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• pp.1089-1092
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• 1995

A planar vibratory gyroscope using electrostatic actuation and electromagnetic detection is proposed. The gyroscope has large sensitivity and can be fabricated by using surface micrimachining, bulk micromachining and conventional machining technology. In this paper, the gyroscope and the electromagnetic detecting system equations are derived to determine the output characteristics for the planar vibratory gyroscope using electrostatic acturation and electromagnetic detection. The maximum output is obtained when the driving frequencyequals to the detecting frequency. The resonant frequencies of the resonator are determined by the beam stiffness, i.e. the material constants and spring dimensions. The dimensions of the beams are determined using the analytic vibration modelling. The expected resonant frequencies are 200Hz both and the sensitivity is 62mV/deg/sec with 4000 electronic circuit amplifying coefficient for an AC drive voltage of 3V bias voltage of 15V and DC field current of 50 mA.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2015년도 추계학술대회 논문집
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• pp.242-243
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• 2015

Fault detection using optical emission spectra with modified K-means cluster analysis and principal component anal ysis are demonstrated for inductive coupl ed pl asma cl eaning processes. The optical emission spectra from optical emission spectroscopy (OES) are used for measurement. Furthermore, Principal component analysis and K-means cluster analysis algorithm is modified and applied to real-time detection and sensitivity enhancement for fluorocarbon cleaning processes. The proposed techniques show clear improvement of sensitivity and significant noise reduction when they are compared with single wavelength signals measured by OES. These techniques are expected to be applied to various plasma monitoring applications including fault detections as well as chamber cleaning endpoint detection.

• 한국안전학회지
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• 제20권1호
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• pp.30-35
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• 2005

This study proposes construction of through transmission for weld defects detection of rail weld zone from ultrasonic signals. For these purposes, the ultrasonic signals for defects(porosity and crack) of weld zone in rails are acquired in the type of time series data and echo strength. 6 lines in the distance amplitude characteristics curve(DACC) indicated damage evaluation standard of weld zone in rails. The acquired ultrasonic signals agree flirty well with the mesured results of reference block and sensitivity block(defect location beam propagation distance, echo strength, etc). The proposed construction of through transmission in this study can be used for weld defects detection of rail weld zone.

• 핵의학기술
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• 제15권1호
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• pp.121-125
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• 2011

배경 : B형간염표면항원(HBsAg)은 B형간염의 진단에 있어 가장 중요한 혈청학적 지표 중 하나이다. HBsAg 검사에 대한임상검사실의 수요에 맞추어 자동화 장비 및 검사법이 계속 개발되어 왔다. 본 연구는 국내에 보급된 RIAKEY, BNIBT, RIAKEY Ultra Sensitive HBsAg, ROCHE 키트의 민감도 및 변이형 검출능과 CLIA법의 CENTAUR 장비와 RIAKEY Ultra Sensitive HBsAg의 상관계수를 알아보고자 하였다. 방법 : WHO $1^{st}$ International Standard 1985(80/549), WHO $2^{nd}$ International Standard 2003 (00/588) 표준물질 2개를 이용하여 농도별 0.08, 0.04, 0.02, 0.01, 0.005 IU/ml 까지 계단희석을 시행하였으며, Subtype ad 9종, Subtype ay 변이시료 1종을 이용하여 RIAKEY, BNIBT, RIAKEY Ultra Sensitive HBsAg, ROCHE 키트를 이용하여 시행하였다. 그리고, 아형 검출에 사용된 변이시료 10종에 대한 IRMA법의 RIAKEY Ultra Sensitive HBsAg와 CLIA법의 CENTAUR 장비를 이용한 상관계수를 비교하였다. 결과 : 표준물질의 농도별 측정 시 WHO 0.01 PANEL 에서 Index 1.0 이상의 결과 값을 얻었으며, 그 결과 민감도는 0.01 IU/ml로 측정되었다. RIAKEY Ultra sensitve HBsAg 키트가 민감도측면에서 우수함을 알 수 있었다. RIAKEY Ultra sensitve HBsAg IRMA 키트에서는 adw2 9종과 ayw1 1종의 변이형 형태에 따라 모두 Index 1.0 이상으로 혈청중의 HBsAg을 100% 측정할수 있었다. RIAKEY Ultra sensitive HBsAg와 CLIA의 결과가 Y=1.0075 X + 1.2434, $R^2$=0.9982으로 우수한 상관성을 보였다. 결론 : 4세대인 IRMA법의 Ultra Sensitive HBsAg 키트로 혈청중의 HBsAg과 여러 가지 아형을 신속하고 정확히 측정하여 질병을 진단 할 수 있을 것으로 여겨진다.

• Childhood Kidney Diseases
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• 제22권2호
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• pp.47-51
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• 2018

Purpose: Urinary tract infection (UTI) is one of the common infectious diseases in children. Several imaging modalities can be used to confirm the presence of acute pyelonephritis (APN). Among them the 99mTcdimercaptosuccinic acid renal scan (DMSA scan) is used as a gold standard for diagnosis. Ultrasonography technology is evolving. Therefore, in this study, we investigated the sensitivity and specificity of Power Doppler ultrasonography (PDU) compared to the results from the previous study. Methods: There were 260 patients included in this study, aged between 1 and 12 months old. The patients were admitted to the Yeungnam University Medical Center between January 2008 and December 2015. All patients underwent both DMSA scan and PDU within 5days of admission. Voiding cystourethrography (VCUG) was performed in 195 patients with abnormal DMSA scan or PDU. Results: The diagnostic sensitivity of APN using PDU was 45.5% and specificity was 85.5% in 260 patients following detection of a defect on DMSA scan that was defined as APN. The diagnostic sensitivity and specificity of PDU for VUR were 65.5 % and 60.1%, respectively. The diagnostic sensitivity and specificity of DMSA scan for VUR were 95.7% and 14.1%, respectively. Conclusion: PDU has a high specificity but low sensitivity, so there are limitations in using it to replace a DMSA scan for the diagnosis of APN in children. DMSA scan and PDU have different sensitivity and specificity in diagnosis of VUR, respectively. Therefore, we suggest that the sensitivity and specificity of each test can be helpful in diagnosing APN and VUR when used in conjunction.

• 소음진동
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• 제9권6호
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• pp.1152-1156
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• 1999

In this study, a fiber optic air-backed mandrel hydrophone has been constructed and performance of acoustic signal detection has been measured. The hydrophone is based on a Mach-Zehnder interferometer with 35 m of sensing fiber. The sensitivity is measured up to -128 dB re rad/$\mu$ Pa in range from 1.4 kHz to5 kHz. A system with this design of hydrophone may be applied to detect low frequency underwater acoustic signals.

• 제어로봇시스템학회논문지
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• 제15권8호
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• pp.818-822
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• 2009

In this paper, we consider a decentralized observer design problem for fault detection in large-scaled linear time-invariant systems. Since the fault detection residual is desired to be sensitive on the fault, we use the H_ index performance criterion. Sufficient conditions for the existence of such an observer is presented in terms of linear matrix inequalities. Simulation results show the effectiveness of the proposed method.

• 한국수산과학회지
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• 제32권3호
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• pp.256-260
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• 1999

본 연구는 EEC 4-plate법과 그 변법 그리고 식품공전상 간이검사법으로써 어류질병의 예방 및 치료에 사용되는 28종류의 항균물질에 대한 최저 검출한계를 서로 비교하여 어체내 잔류 항균물질의 최적 간이검사법 (bioassay)으로서의 유효성을 확인하고자 하였다. 식품공전상 간이검사법은 PCs에 뛰어난 검출감도를 나타내었으며 AGs에 대하여 좋은 감도를 보였으나 TCs, MLs, NFs, QNs에 대해서는 낮은 검출감도를 나타내었다. 한편, SAs에 대하여는 대단히 저조한 감도를 보였다. EEC 4-plate변법은 TCs에 대하여 우수한 검출감도를 나타내었다. EEC 4-plate법 및 그 변법은 PCs, MLs, NFs, QNs, SAs에 대하여 상대적으로 높은 검출감도를 나타내었다. 시험법들은 모두 CMs에 대하여는 검출감도가 낮았다. 결국 EEC 4-plate 변법이 여러계열의 항균물질에 대해 검출감도가 뛰어나고 항균활성의 범위가 넓어 어체내 잔류 항균성물질을 가장 유효하게 스크리닝할 수 있는 간이검사법으로 확인되었다.

• Imaging Science in Dentistry
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• 제49권4호
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• pp.265-272
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• 2019

Purpose: To compare the diagnostic accuracy of cone-beam computed tomography (CBCT) with that of parallel(PPA) and oblique projected periapical(OPA) radiography for the detection of different types of peri-implant bone defects. Materials and Methods: Forty implants inserted into bovine rib blocks were used. Thirty had standardized bone defects(10 each of angular, fenestration, and dehiscence defects), and 10 were defect-free controls. CBCT, PPA, and OPA images of the samples were acquired. The images were evaluated twice by each of 2 blinded observers regarding the presence or absence and the type of the defects. The area under the receiver operating characteristic curve (AUC), sensitivity, and specificity were determined for each radiographic technique. The 3 modalities were compared using the Fisher exact and chi-square tests, with P<0.05 considered as statistical significance. Results: High inter-examiner reliability was observed for the 3 techniques. Angular defects were detected with high sensitivity and specificity by all 3 modalities. CBCT and OPA showed similar AUC and sensitivity in the detection of fenestration defects. In the identification of dehiscence defects, CBCT showed the highest sensitivity, followed by OPA and PPA, respectively. CBCT and OPA had a significantly greater ability than PPA to detect fenestration and dehiscence defects(P<0.05). Conclusion: The application of OPA radiography in addition to routine PPA imaging as a radiographic follow-up method for dental implantation greatly enhances the visualization of fenestration and dehiscence defects. CBCT properly depicted all defect types studied, but it involves a relatively high dose of radiation and cost.

• 전산구조공학
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• 제9권4호
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• pp.117-126
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• 1996

구조물의 손상추정법은 정적방법과 동적방법으로 나눌 수 있다. 정적방법은 정적하중과 정적변위의 관계를 이용하여 구조물의 손상위치와 손상정도를 추정하는 방법으로 동적방법에 비해 수식이 간단하나, 정적하중과 정적변위의 관계만을 사용하여 구조물의 손상을 추정하므로 정적변위에 대한 오차에 매우 민감하다. 동적방법은 구조물의 고유한 진동특성을 나타내는 고유진동수와 진동모우드를 구하여 구조물의 손상을 추정하는 방법으로, 정적방법에 비해 동일한 측점에서 많은 양의 시간기록자료를 계측할 수 는 있으나, 신뢰성이 높은 많은 수의 고유진동수와 진동모우드를 구하기가 어렵다. 본 연구에서는 구조물의 정적변위, 고유진동수와 진동모우드에 대한 민감도행렬을 사용하여 구조물의 정적 및 동적특성을 동시에 고려할 수 있는 구조물의 손상추정법을 제시하였다. 제시한 방법은 구조물의 손상 전.후의 정적변위와 진동모우드의 변화량을 부등구속조건식으로한 최적화기법을 사용하므로, 제한된 계측절점과 오차를 고려할 수 있으며 정적변위와 모우드 민감도행렬이외의 다양한 구조적 특성에 대한 민감도를 구속조건식으로 사용할 수 있다. 트러스구조물에 대한 모의 수치예제를 통한 제안한 방법의 정확성과 효율성을 수치적으로 검증하였다.