• 설비공학논문집
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• 제23권1호
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• pp.54-60
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• 2011

Procedures for estimation of insulation thickness for a horizontal pipe for condensation control or personnel protection has been investigated, parallel to the previous work of a vertical wall case. Parameters include pipe diameter, emissivity, thermal conductivity, and operating temperatures. The results indicated that the surface emissivity plays a very important role in the design of insulation, specially for the case of high temperature application with low Bi. The effect of surface radiation in such case could be up to 65% of the total. Required insulation thickness for the surface temperature control increases as pipe diameter increases and as surface emissivity decreases. Adequate revision of specifications or standards to include newly invented insulation materials with high emissivity has been also suggested.

• 한국경영과학회:학술대회논문집
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• 한국경영과학회 2003년도 추계학술대회 및 정기총회
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• pp.201-204
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• 2003

A hybrid artificial intelligence approach based on combining case based reasoning and neural networks is presented. The approach is designed to allow for solving blowing control of BOF(basic oxygen furnace), example of which lie at the core of steelmaking process control systems application in the steel industry. According to this hybrid approach, the system, when faced with a new problem, first retrieves similar cases and neural network is used to solve the problem. Experimental Results indicate that combining case based reasoning and neural network offers an efficient approach to solving control and prediction problem

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1996년도 추계학술대회 논문집
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• pp.267-271
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• 1996

In this study, performance improvement of the inverse modeling as the on-line control method for the estimation, control experiment is performed. As the modeling errors is occurred in duct system arbitrarily, a case using the filtered-x LMS algorithm only as the control method, a case using tile inverse modeling method only and a case using the inverse modeling with the adaptive line enhancer are compared. The estimation errors between real secondary path transfer functions and the estimated and the control performances of primary noises with these estimated transfer functions are compared.

• 동의신경정신과학회지
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• 제15권1호
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• pp.197-209
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• 2004

Objectives : The purpose of this case-control research was to investigate the effects of acupuncture stimulation on autonomic nervous system for patients with HRV and to find out relationship with anti-stress effects. Methods : The study group consists of 24 patients with self-recognition of stress as the case group, and 20 normal person as the control group by similar age. We measured HRV of case and control groups before acupuncture stimulation, prick acupuncture in Hegu(LI4), Taichong(Liv3), Shenme(H7), Neiguan(P6), Zusanli(S36). After treating for 20 minutes, measurement values of HRV and PSV were compared for pre-acupuncture and post-acupuncture. Results : 1. LF norm, HF norm, LF/HF between the case and control groups were significant different in HRV before acupuncture stimulation in the 1st experiment. 2. HRT, SDNN, SDSD, LF norm, HF norm, and LF/HF of the case group were significant different in HRV after acupuncture stimulation in the 1st experiment. HRT of the case group was significantly different in HRV after acupuncture stimulation in the 1st experiment. 3. LF norm, HF norm, LF/HF of the case group were significant different between the 1st and 2nd experiment in HRV before acupuncture stimulation. 4. LF norm, HF norm, and LF/HF were significant different between the 1st and 2nd experiment in HRV of patients whose symptoms improved. But HRV of patients whose symptoms unimproved didn't show significant difference. Conclusion : The results suggest that acupuncture stimulation is associated with changed activity in the sympathetic and parasympathetic nervous system. Measurement values of HRV is suitable to estimate the activity of automatic nervous system.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2004년도 ICCAS
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• pp.896-902
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• 2004

The purpose of the study of multi-robot system is to realize multi-robot system easy for the control of robot system in case robot is adapted in the complicated environment of task structure. The purpose of the study of multi-robot system is to realize multi-robot system easy for the control of robot system in case robot is adapted in the complicated environment of task structure. To make real time control possible by making effective use of recognized information in this dynamic environment, suitable distribution of tasks should be made in consideration of function and role of each performing robots. In this paper, IHMA (Intelligent Hybrid Modular Architecture) of Intelligent combined control architecture which utilizes the merits of deliberative and reactive controllers will be suggested and its efficiency will be evaluated through the adaptation of control architecture to representative multi-robot system.

• 제어로봇시스템학회논문지
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• 제5권2호
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• pp.151-157
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• 1999

In this paper, an integrated nonlinear sliding mode observer and controller has been designed in order to control of an automotive engine idle speed. The primary objective of the engine idle speed control is to maintain the desired engine idle speed despite of various torque disturbances via estimating air mass flow at the location of the injector in intake manifold by using a sliding mode observer. Simulation results show that the case where both throttle angle and ignition time are used as control inputs outperforms the case where just only throttle angle is used as a control input.

• International Journal of Control, Automation, and Systems
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• 제6권3호
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• pp.339-350
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• 2008

A general active fault-tolerant control framework is proposed for nonlinear systems with sensor faults. According to their identifiability, all sensor faults are divided into two classes: identifiable faults and non-identifiable faults. In the healthy case, the control objective is such that all outputs converge to their given set-points. A fault detection and isolation module is firstly built, which can produce an alarm when there is a fault in the system and also tell us which sensor has a fault. If the fault is identifiable, the control objective remains the same as in the healthy case; while if the fault is non-identifiable, the control objective degenerates to be such that only the healthy outputs converge to the set-points. A numerical example is given to illustrate the effectiveness and feasibility of the proposed method and encouraging results have been obtained.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1998년도 제13차 학술회의논문집
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• pp.513-518
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• 1998

In this paper, a robust fault-tolerant control scheme for robot manipulators overcoming actuator failures is presented. The joint(or actuator) fault considered in this paper is the free-swinging joint failure and causes the loss of torque on a joint. The presented fault-tolerant control framework includes a normal control with normal(non-failed) operation, a fault detection and a fault-tolerant control to achieve task completion. For both no uncertainty case and uncertainty case, a stable normal con-troller and an on-line fault detection scheme are presented. After the detection and identification of joint failures, the robot manipulator becomes the underactuated robot system with failed actuators. A robust adaptive control scheme of robot manipulators with the detected failed-actuators using the brakes equipped at the failed(passive) joints is proposed in the presence of parametric uncertainty and external disturbances. To illustrate the feasibility and validity of the proposed fault-tolerant control scheme, simulation results for a three-link planar robot arm with a failed joint are presented.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 하계학술대회 논문집 D
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• pp.2254-2258
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• 2003

In recent years, the case to install small water treatment facility to every local area has increased. A key issue in the successful implementation of the control systems for the water treatment plants is the choice of control architecture. Within the framework of distributed control system(DCS), this paper presents a new development of intelligent control module and its novel application to open control architecture for water treatment plants. This control system so called NCS(Network Based Control System) with standard networks system with LonTalks protocol of ANSI/EIA 709.1, regulatory control function and information dispatch function has suitable functionality to operate these distributed water treatment facility effectively. This paper describes the case where NCS is applied for the filters system in water treatment facility of Heong Sung area.

• 한국해양공학회지
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• 제33권2호
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• pp.139-145
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• 2019

It is important that an MGO Chiller System, which is one of the sulfur oxide emission control technologies, is designed to meet the fuel temperature requirements, even with sudden engine load changes. Three different control algorithms (PI, Cascade, and MPC) were applied to an indirect MGO chiller system to compare and analyze the outlet temperature dynamic characteristics of the system through a case study. The results showed that the MPC control method had the best temperature following characteristics in the case study, and the temperature deviation range was reduced by approximately 5% compared to the PI control method.