• Journal of Advanced Marine Engineering and Technology
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• v.21 no.4
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• pp.393-403
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• 1997

In this paper, we proposed an optimal identification method of identifying the membership func¬tions and the fuzzy rules for the stabilization controller of the nonlinear system by RVEGA( Real Variable Elitist Genetic Algo rithm l. Although fuzzy logic controllers have been successfully applied to industrial plants, most of them have been relied heavily on expert's empirical knowl¬edge. So it is very difficult to determine the linguistic state space partitions and parameters of the membership functions and to extract the control rules. Most of conventional approaches have the drastic defects of trapping to a local minima. However, the proposed RVEGA which is similiar to the processes of natural evolution can optimize simulta¬neously the fuzzy rules and the parameters of membership functions. The validity of the RVEGA - based fuzzy controller was proved through applications to the stabi¬lization problems of an inverted pendulum system with highly nonlinear dynamics. The proposed RVEGA - based fuzzy controller has a swing -. up control mode(swing - up controller) and a stabi¬lization one(stabilization controller), moves a pendulum in an initial stable equilibrium point and a cart in an arbitrary position, to an unstable equilibrium point and a center of the rail. The stabi¬lization controller is composed of a hierarchical fuzzy inference structure; that is, the lower level inference for the virtual equilibrium point and the higher level one for position control of the cart according to the firstly inferred virtual equilibrium point. The experimental apparatus was imple¬mented by a DT -- 2801 board with AID, D/A converters and a PC - 586 microprocessor.

• Journal of Practical Engineering Education
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• v.6 no.2
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• pp.91-97
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• 2014

Education equipment for field programmable gate array (FPGA) based multimedia player design is introduced. Using the education equipment, an example of hardware design for color detection and augment reality (AR) game is described, and an example of syllabus for "Digital system design using FPGA" course is introduced. Using the education equipment, students can develop the ability to design some hardware, and to train the ability for the creative capstone design through conceptual, partial-level, and detail designs. By controlling audio codec, system-on-chip (SOC) design skills combining a NIOS II soft microprocessor and digital hardware in one FPGA chip are improved. The ability to apply wireless communication and LabView to FPGA-based digital design is also increased.

• Journal of Biomedical Engineering Research
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• v.44 no.1
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• pp.19-24
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• 2023

Due to the spread of COVID-19, many patients with severe respiratory diseases have occurred worldwide, and accordingly, the use of mechanical ventilators has exploded. However, hospitals do not have systematic risk management, and the Medical Device Regulation also provides medical device risk management standards for manufacturers, but does not apply to devices in use. In this paper, we applied the Failure Mode Effects Analysis (FMEA) risk analysis technique based on the International Standard ISO 14971 (Medical Devices-Application of risk management to medical devices) for 85 mechanical ventilators of a specific model in use in hospitals. Failure modes and effects of each parts were investigated, and risk priority was derived through multiplication of each score by preparing criteria for severity, occurrence, and detection for each failure mode. As a result, it was confirmed that the microprocessor-based Patient Unit/Monitoring board in charge of monitoring scored the highest score with 36 points, and that reliability management is possible through systematic risk management according to priority.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.17 no.2
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• pp.353-368
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• 2023

The four wing unmanned aerial vehicle owns the characteristics of small size, light weight, convenient operation and well stability. But it is easily disturbed by external environmental factors during flight with these disadvantages of short endurance and poor attitude solving ability. For solving these problems, a microprocessor based on STM32 chip is designed and the overall development is completed by the resources such as built-in timer and multi-function mode general-purpose input/output provided by the master micro controller unit, together with radio receiver, attitude meter, barometer, electronic speed control and other devices. The unmanned aerial vehicle can be remotely controlled and send radio waves to its corresponding receiver, control the analog level change of its corresponding channel pins. The master control chip can analyze and process the data to send multiple sets pulse signals of pulse width modulation to each electronic speed control. Then the electronic speed control will transform different pulse signals into different sizes of current value to drive the motor located in each direction of the frame to generate different rotational speed and generate lift force. To control the body of the unmanned aerial vehicle, so as to achieve the operator's requirements for attitude control, the PID controller based on Kalman filter is used to achieve quick response time and control accuracy. Test results show that the design is feasible.

• Journal of the Korean Institute of Telematics and Electronics
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• v.15 no.1
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• pp.19-22
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• 1978

A modular microcomputer system based on the Intel 8080 microprocessor is designed. Each module communicate via common bus system. The different modules can be placed anywhere on the bus. Address for memory and I/O modules are determined by switch registers situated on the modules. The system is intended to be used as a base equipment for continuing study, expansion, development and for teaching students.

• Journal of the Korean Society for Precision Engineering
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• v.2 no.1
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• pp.72-81
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• 1985

This paper deals with the Z-8000 microprocessor based optimal controller problem of large rotating system. Control algorithm consists of Global Mode and Fine Mode. In Global Mode, motor is driven with maximum torque, while, in Fine Mode, the speed of response and overshoot improved by multi-gains. Friction term of the plant was measured in the 1-st test, jerking effect by the nonlinearity of friction was compensated in the 2-nd test and the 3-rd test was carried out to finalize the control system model. Test results show that the speed of response and overshoot are highly improved.

• Journal of Institute of Control, Robotics and Systems
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• v.7 no.1
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• pp.1211-1217
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• 2001

This paper presnts a controller for the heat capacity of thermal storage systems using off-peak electricity which is composed of an identifier using neural networks and a storage time adjuster in order to store exactly the required thermal energy without loss. Since thermal storage systems have nonlinear characteristics and large time constant, even if we predict the heating load accurately, it is very difficult to store exactly the required thermal energy. Thus, in the neural network for the identifier, the adaptive learning rate for high learning speed and bit inputs based on state changes of thermal storage power source are used. Also a hardware for the controller using a microprocessor is developed. The performance of the proposed controller is shown by experiment.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.1816-1821
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• 2003

The thermoelectric device was applied to a car-seat to control the hot temperature in summer and cold temperature in the winter. The characteristics of the device used to a car-seat were analyzed. The air conditioning structure was designed to regulate the hot side of the thermoelectric device. To control the temperature of the car-seat, a robust control algorithm based on the sliding mode control was applied, and a controller using one-chip microprocessor was developed. The performance of the proposed controller through experiments was shown.

• Proceedings of the IEEK Conference
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• 2004.06b
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• pp.423-426
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• 2004

본 논문에서는 저 전력 마이크로프로세서를 개발하기 위해 ARM7 마이크로프로세서와 명령어 호환을 갖는 32비트 RISC 구조의 마이크로프로세서를 설계하였다. 저 전력 ARM7 마이크로프로세서 IP 구현을 위하여 새로운 정수 나눗셈 명령어를 정의하고 이를 적용하는 회로를 설계하여 제수가 피제수보다 큰 경우 6.4nW, 그 이외의 경우에는 76.5 nW를 소모하여 기존의 방법보다 $140{\~}860\%$ 까지 개선되었음을 측정하였다. 또한 Multi-cycle 명령어 발생시 Prefetch에 의한 전력 소모를 줄이기 위하여 명령어의 condition code를 미리 결정함으로써 $50\%$의 prefetch 동작 횟수를 줄였다. 그 결과 저 전력 파이프라인의 경우에는 1.943mW/1MHz의 소비 전력이 측정되었다.

• Proceedings of the Acoustical Society of Korea Conference
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• 1985.10a
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• pp.47-49
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• 1985

In most of ultrasonic NDT(Non-Destructive Testing) equipments using A-scan display technic, it is one of the inconveniences that the user must be proficient in reading the displayed signals for the accurate decisions. In this study, a simple microprocessorized NDT machine for the flaw detection was developed. The operation of system is based on the conventional NDT system. The microprocessor detects the time delay between transmitted pulse and echos by counter-measure method. Then according to the scanning position, the location of flaw orthe other side of testing object is plotted on the CRT. The main advantages of the developed system are simplicity in handling, recording capability of measured data, and low cost.