• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1991년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 22-24 Oct. 1991
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• pp.71-75
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• 1991

This paper deals with designing a real-time fault and accommodation system. The LQG controller is adopted in the normal state and the output of LQG controller is corrected using Separated Bias Estimator in the faulty state. The proposed scheme has been applied to the two-tank control system and showed satisfactory performance.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.1871-1876
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• 2005

In this paper, We present a new nonlinear adaptive control law using a disturbance accommodating control (DAC) observer for a Japanese automatic landing flight experiment vehicle called ALFLEX. A future spaceplane must have ability to deal with greater fluctuations in the stability and control derivatives of flight dynamics, because its flight region is much wider than that of conventional aircraft. In our previous studies, digital adaptive flight control systems have been developed based on a linear-parameter-varying (LPV) model depending on dynamic pressure, and obtained good simulation results. However, under previous control laws, it is difficult to accommodate uncertainties represented by disturbance and nonlinearity, and to design a stable flight control system. Therefore, in this study, we attempted to design a nonlinear adaptive control law using the DAC Observer and inverse dynamic methods. A good tracking property of the obtained system was confirmed in numerical simulation.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1992년도 한국자동제어학술회의논문집(국제학술편); KOEX, Seoul; 19-21 Oct. 1992
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• pp.130-134
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• 1992

The ability of a robot system to comply to an environment via the control of tool-environment interaction force is of vital for the successful task accomplishment in many robot application. This paper presents the implementation of external force control for two dimensional contour following task using a commercial robot system. Force accommodation is used since a constraint imposed in our work is not to modify the commercial robot system. A linear, decoupled model of two dimensional contour following system in the discrete time domain is derived first. Then the experimental verification of linear control is obtained using a PUMA 560 manipulator with standard Unimation controller, Astek FS6-120A six axis wrist force sensor attached externally to the arm and LSI-11173 microcomputer. Experimentally obtained data shows that the RMS contact force error is 0.8246 N when following the straight edge and 2.3768 N when following 40 mm radius curved contour.

• 대한기계학회논문집
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• 제8권5호
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• pp.488-497
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• 1984

본 연구에서는 Fig.1과 같은 조립용 손목을 개발하였는데, 유연성의 구조는 RCC의 원리를 이용하고, 감지성은 Hi-Thand에서 채택한 스트레인 게이지 방식을 적용 하였다. 이 조립용 손목의 성능실험은 조립될 부품간의 틈새율, 부품의 길이 그리고 오차의 크기에 따라 수행하였으며, 조립시 스트레인 게이지로부터 측정되는 반력들은 D.E.Whitney의 조립이론식을 적용하여 구한 이론치와 비교하여 보았다. 반력을 측정 하는 궁극적인 목적은 이 측정치를 이용하여 귀환제어함으로써 초기오차를 수정하는 것이기 때문에 귀환제어를 어떻게 하느냐에 따라 조립시 생기는 반력이나 조립시간이 달라진다. 따라서 귀환제어를 위한 제어 알고리즘을 개발하였고 조립시 발생하는 반 력을 컴퓨터 시뮬레이션을 통하여 구해서 귀환제어 시키지 않을시 즉 수정적 방법에 의해서 조립할때에 발생하는 힘과를 비교 분석하였다.

• Biomolecules & Therapeutics
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• 제23권4호
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• pp.350-356
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• 2015

Functional dyspepsia (FD) is a prevalent idiopathic upper gastrointestinal (GI) disorder characterized by diverse symptomatology including epigastric pain or discomfort, postprandial fullness, and early satiety. Although its pathophysiological mechanisms have not yet been fully established, the available studies suggest that the etiology of FD is invariably multifactorial. Benachio-F$^{(R)}$ (BF) is a proprietary liquid formulation of 7 herbal extracts that has been proposed to address this multifactorial etiology using multi-drug phytotherapy. The pharmacological effects of BF, in comparison with those of two other herbal products (Whalmyungsu$^{(R)}$; WM and Iberogast$^{(R)}$; IB) were evaluated in rats. In a laparotomy-induced rat model of delayed GI transit, BF significantly accelerated the delayed gastric emptying caused by morphine, apomorphine, and cisplatin, and also significantly increased mean gastric transit, as compared to the control animals. BF markedly increased gastric accommodation in rats and produced higher gastric volume values than did the control treatment. The effects of BF were generally comparable or superior to those of WM and IB in these models. Furthermore, BF significantly stimulated biliary flow, as compared to the control treatment. These results indicated that BF might have great potential as an effective phytotherapeutic agent capable of reducing GI symptoms and increasing quality of life in FD patients.

• Journal of Electrical Engineering and Technology
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• 제12권2호
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• pp.886-889
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• 2017

An active Fault Tolerant Model Predictive Control (FTMPC) using Fuzzy scheduler is developed. Fault tolerant Control (FTC) system stages are broadly classified into two namely Fault Detection and Isolation (FDI) and fault accommodation. Basically, the faults are identified by means of state estimation techniques. Then using the decision based approach it is isolated. This is usually performed using soft computing techniques. Fuzzy Decision Making (FDM) system classifies the faults. After identification and classification of the faults, the model is selected by using the information obtained from FDI. Then this model is fed into FTC in the form of MPC scheme by Takagi-Sugeno Fuzzy scheduler. The Fault tolerance is performed by switching the appropriate model for each identified faults. Thus by incorporating the fuzzy scheduled based FTC it becomes more efficient. The system will be thereafter able to detect the faults, isolate it and also able to accommodate the faults in the sensors and actuators of the Continuous Stirred Tank Reactor (CSTR) process while the conventional MPC does not have the ability to perform it.

• 대한장애인치과학회지
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• 제2권1호
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• pp.17-30
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• 2006

Federal disability law has evolved from several laws geared to protect people with disabilities since the late 1960s and early 1970s. When U.S. Congress passed the Americans with Disabilities Act (ADA) in 1990, no federal statute prohibited the majority of employers, program administrators, owners and managers of places of public accommodation and others from discriminating against people with disabilities. Toward the ends to assure equality of opportunity, full participation, independent living, and economic self-sufficiency for individuals with the disabilities, the ADA pursues three major strategies: Title I addresses inequality in employment, Title II, inequality in public services, and Title III, inequality in services and accommodations offered by private entities. The purposes of the study were to analyze the impact of the ADA on health care for persons with disabilities and to review the ongoing health policy reforms at the federal and state governments. Essential remedies that the ADA contemplates are based on two principles, simple discrimination and reasonable accommodation, which significantly improved access to quality care, especially long-term care, by persons with disabilities. However, the ongoing Medicaid policy reforms to control rising health care costs in the U.S. could threaten the access to care by persons with disabilities in optional groups and to optional care services by persons with disabilities in mandatory groups.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1993년도 한국자동제어학술회의논문집(국내학술편); Seoul National University, Seoul; 20-22 Oct. 1993
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• pp.119-124
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• 1993

This paper describes a method of producing maps of an indoor environment with an autonomous mobile robot equipped with sonar array. This method uses the certainty grid suitable for accommodation of inaccurate sensor data and real-time navigation. Each grid contains a certainty vale that indicates the measure of confidence that an obstacle exists within th grid area. The scheduled firing method is used to eliminate the crosstalk between ultrasonic sensors. The effectiveness of the method is verified by a series of experiments.

• 한국안광학회지
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• 제17권2호
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• pp.177-184
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• 2012

목적: 본 연구에서는 개인용 컴퓨터로 일정 시간동안 연속적으로 게임을 할 때 안구의 주 운동방향이 조절과 관련된 시기능에 미치는 영향을 알아보고자 하였다. 방법: 안질환 및 조절기능의 이상이 없고 교정시력이 1.0이상이 되는 20대 60명을 대상으로 40분 및 90분 동안 연속적으로 수평방향의 게임과 수직방향의 게임을 각각 시행하도록 한 후 조절력, 조절용이성, 상대조절 및 조절래그 값을 측정하였다. 동일 시간동안 게임을 시행하지 않았을 때를 대조군으로 하여 시기능 값을 비교, 분석하였다. 결과: 게임을 하지 않은 대조군의 조절관련 시기능 검사 값에 비하여 40분 동안의 컴퓨터 게임 후 최대조절력, 조절용이성, 조절래그 및 상대조절은 모두 감소하는 경향을 보였으며, 상대조절을 제외하고는 90분으로 컴퓨터 작업시간을 연장하였을 경우 더욱 감소된 값을 나타내었다. 양성상대조절은 90분 동안의 컴퓨터 게임 후 약간 증가하는 경향을 보였다. 한편, 컴퓨터 게임 시 안구의 주 운동 방향에 따른 시기능의 변화는 수직방향으로의 안구운동보다는 주로 수평방향으로의 운동에 의한 조절기능의 감소가 큼을 알 수 있었다. 결론: 컴퓨터 게임을 통한 VDT 작업의 시간이 길어짐에 따라 전반적인 조절기능의 능력이 감소하는 경향을 보였으며, 수직방향보다는 수평방향으로의 안구이동이 VDT 작업 시 조절기능의 변화에 크게 영향을 주므로 VDT 작업 시 수평방향으로의 잦은 안구이동은 안정피로의 주 원인이 될 것으로 생각할 수 있었다.

• Journal of Electrical Engineering and Technology
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• 제13권2호
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• pp.648-658
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• 2018

Regarding the fact that wind power forecast accuracy is gradually improved as time is approaching, this paper proposes a two-stage rolling dispatch approach based on model predictive control (MPC), which contains an intra-day rolling optimal scheme and a real-time rolling base point tracing scheme. The scheduled output of the intra-day rolling scheme is set as the reference output, and the real-time rolling scheme is based on MPC which includes the leading rolling optimization and lagging feedback correction strategy. On the basis of the latest measured thermal unit output feedback, the closed-loop optimization is formed to correct the power deviation timely, making the unit output smoother, thus reducing the costs of power adjustment and promoting wind power accommodation. We adopt chance constraint to describe forecasts uncertainty. Then for reflecting the increasing prediction precision as well as the power dispatcher's rising expected satisfaction degree with reliable system operation, we set the confidence level of reserve constraints at different timescales as the incremental vector. The expectation of up/down reserve shortage is proposed to assess the adequacy of the upward/downward reserve. The studies executed on the modified IEEE RTS system demonstrate the effectiveness of the proposed approach.