• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1987년도 한국자동제어학술회의논문집; 한국과학기술대학, 충남; 16-17 Oct. 1987
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• pp.161-163
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• 1987

An FTCS is developed for the purpose of improving the reliability of a process control system. The proposed FTCS has capabilities of failure detection, back-up control, graphic display, and self-checking. Also the FTCS is combined with the process simulator to experiment in laboratory for the evaluation of performance of operation. The FTCS is applied to Thermal Power Plant .

• 대한전기학회:학술대회논문집
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• 대한전기학회 1987년도 전기.전자공학 학술대회 논문집(I)
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• pp.201-204
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• 1987

To improve the reliability of boiler controller of a power plant, FTCS(Fault Tolerant Control System) is proposed. We studied to implement a Multi-processor scheme for FTCS. This paper presents the total system to experiment the performance of FTCS and the Multi-processor scheme implemented.

• 대한두경부종양학회지
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• 제14권1호
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• pp.70-75
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• 1998

Tumor growth and metastasis depends on angiogenesis. Vascular endothelial growth factor (VEGF) is a potent mitogen for vascular endothelial cells in vitro and promotes neoangiogenesis in vivo. Objective: Follicular thyroid cancers(FTC) are a vascular tumor and traditionally metastasize via blood vessels. Likely other cancers, angiogenesis may playa important role in FTC. We, therefore, investigated the expression of VEGF and microvascular density by immunohistochemistry in FTC and follicular adenoma(FA). Materials and Methods: Findings of immunohistochemical stainings for VEGF and CD31 were measured by grading scale from +1 to 4+(strongest) and by counting the stained microvessels in 14 FTCs and 14 FAs. Results: 1) Expression of VEGF. a) FTCs have stronger expression than FAs in areas of tumor adjacent to capsule($mean{\pm}SD\:\;3.2{\pm}0.9\;vs\;2.0{\pm}0.9$, p<0.01) and in central area($2.3{\pm}0.7\;vs\;1.3{\pm}0.6$, p<0.01). b) The VEGF expression of capsular area in FTCs are higher than that of central area(p<0.05). 2) Microvascular density by CD31. a) FTCs have more microvessels than FAs in areas of adjacent to capsule($78.9{\pm}27.3\;vs\;38.7{\pm}15.6$, p<0.01) and in central area($75.5{\pm}23.3\;vs\;27.8{\pm}10.7$, p<0.01). b) In FTCs, the number of microvessels of capsular area are more than that of central tumor area, but not significant statistically(p>0.05). Conclusion: The higher expression of VEGF and microvascular density in FTC suggests angiogenesis plays an important role in progression of FTC.

• 대한전자공학회논문지
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• 제24권1호
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• pp.28-34
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• 1987

As a means of improving the reliability of a process control system, a FTCS(Fault Tolerant Control System) is designed and applied to the boiler controller of a thermal power plant. The proposed FTCS has capabilities of fault detection and diagnosis as well as back-up control and bumpless switching. A prototype of FTCS is implemented on an IBM PC as an add-on system and it is experimentally verified by using a boiler process simulator together with simplified analog controllers and a switching unit that an one-fold fault is detected in real time and back-up controller takes over the role of the original controller, controlling the faulty loop.

• 대한산업공학회지
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• 제41권2호
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• pp.121-127
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• 2015

A reduction of motor performance due to brain disorders can be screened by evaluating force tracking capabilities (FTCs). Existing studies have examined FTCs mainly using simple sinusoidal waves, of which repeated profiles have a critical limitation due to a learning effect in force tracking. The present study examined the effects of personal factors (age and gender) and sinusoidal wave factors (central force and complexity) on FTCs of healthy adults using composite sinusoidal wave profiles (CSWPs). FTCs were measured using Finger $Touch^{TM}$ for 30 seconds and quantified in terms of time within the target range (TWR, accuracy measure) and relative RMSE (RRMSE, variability measure). A total of 90 healthy adults in 20s to 70s with the equal gender ratio participated in the experiment consisting of combinations of 2 central force levels (6 N and 10 N) and 2 complexity levels (approximate entropy, ApEn = 0.03 and 0.06) of CSWPs. Significantly decreased FTCs (lower TWR and higher RRMSE) were found in aged adults, females, the low central force, and the high complexity. The detailed FTC decrements include a 43% reduced TWR and a 85% increased RRMSE of older adults in 70s as compared to those in 20s, a 17% reduced TWR and a 17% increased RRMSE of female as compared to those of male, a 30% reduced TWR and a 108% increased RRMSE at central force = 6N when compared to those at central force = 10N, and a 19% reduced TWR and a 30% increased RRMSE at ApEn = 0.06 as compared to those at ApEn = 0.03. The characteristics of FTCs for CSWPs can be of use in establishing an assessment protocol of motor performance for screening brain disorders.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1989년도 추계학술대회 논문집 학회본부
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• pp.372-375
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• 1989

In this paper, a new FTCS with the ability to perform original control objective without considerable loss of control performance in the face of any fault is proposed. The FTCS is composed of two interacting units, Adaptive Controller Unit and Fault Detection/Classification, where ACU performs primary control objective with basic process information(I/O) and environmental information fed by FDU and where FDU detect and classify faults and make decision on remidial action by the use of information provided by ACU.

• Asian Pacific Journal of Cancer Prevention
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• 제13권5호
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• pp.2175-2178
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• 2012

Purpose: Definite diagnosis of follicular thyroid carcinoma (FTC) is based on the presence of capsular or vascular invasion. To date, no reliable and practical method has been introduced to discriminate this malignant neoplasm from follicular thyroid adenoma (FTA) in fine needle aspiration biopsy material. Matrix metalloproteinase-2 (MMP-2), by degrading extracellular matrix, and caspase-3, by induction of apoptosis, have been shown to play important roles in carcinogenesis and aggressive behavior in many tumor types. The aim of this study was to examine expression of MMP-2 and caspase-3 in thyroid follicular neoplasms and to determine their usefulness for differential diagnosis. Method: Sixty FTAs and 41 FTCs were analysed immunohistochemically for MMP-2 and caspase-3. Result: MMP-2 was positive in 4 FTCs (9.8%), but in none of FTAs, with statistical significance (p= 0.025). Caspase-3 was positive in 30 (50%) of FTAs and in 27 (65.9%) of FTCs. Conclusion: Our results show MMP-2 expression only in FTCs and suggest that this protein may be a useful marker to confirm diagnosis of FTC versus FTA with 100% specificity and 100% predictive value of a positive test. We failed to show any differential diagnostic value for caspase-3 in thyroid follicular neoplasms.

• 한국지반공학회지:지반
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• 제13권3호
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• pp.5-20
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• 1997

본 연구에서는 유한변형률 이론에 근거하여 3차원 압밀 지배 방정식을 유도하였다. 이 방정식은 비교적 압밀층의 두께가 두꺼운 경우, 비선형 물성치, 공극비에 따른 비선형 투수계수를 갖는 지반에 적합하다. 기존의 유한차분 수치해석 기법(FTCS)은 지배 방정식이 비선형 이며 복잡한 경우 안정된 해를 얻을 수 없기 때문에 본 연구에서는 특수 유한 차분 기법을 도입하였다. 이 수치해석 기법을 지배 방정식에 적용하면 시간에 따른 압밀량을 예측할 수 있다. 본 해석기법에 의해 구해진 값들을 윅드레인을 설치한 여러 가지 고압축성 토질에서의 실험 결과와 비교한 결과, 최종 압밀량과 시간에 따른 압말량이 잘 일치하고 있다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1987년도 전기.전자공학 학술대회 논문집(I)
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• pp.213-215
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• 1987

As a means of improving the reliability of the analog type controller for the thermal power plant, an efficient method is proposed, which is to place the hardware redundancy, i.e. a back-up controller with fault detecting capability. FTCS is implemented by using multi-processors and it is experimentally verified that the back-up controller takes over the role of the original controller, controlling the faulty loop.

• 전력전자학회논문지
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• 제7권4호
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• pp.366-376
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• 2002

본 논문에서는 직접토크제어 유도전동기 구동시스템의 고 신뢰성 운전을 위한 센서이상 검출식별 및 이상허용제어에 관한 실험적 연구 결과를 기술한다. 주요 내용은 센서이상 해석 결과의 실험적 검증과 이상검출식별 시스템의 설계, 이상허용제어기의 구현 및 실험적 성능 고찰이다. 적용된 센서이상 검출식별기법은 관측기기반 기법이며 기존의 다중 관측기 기법과 달리 한 개의 관측기에 의해 검출식별정보를 발생하므로 실시간 적용이 용이하다. 제안된 시스템의 성능을 검증하기 위하여 2.2kW 유도전동기를 대상으로 직접토크제어 기법을 이용한 속도제어시스템을 설계하였다. 이상허용제어를 위한 시스템의 하드웨어는 고성능 DSP인 TMS320VC33을 이용한 제어보드와 IPM을 이용한 전력회로로 구성된다. 다양한 센서이상에 대한 실험결과, 설계된 시스템의 검출식별 및 이상허용 제어 성능이 매우 우수함을 확인하였다.