• The KIPS Transactions:PartA
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• v.16A no.5
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• pp.357-368
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• 2009

Mobile IP storage has been proposed to overcome storage limitation in the flash memory and hard disks. It provides almost capacity-free space for mobile devices over wireless IP networks. However, battery lifetime of the mobile devices is reduced rapidly because of power consumption with continuous use of a WLAN device when multimedia contents are being streamed through the mobile IP storage. This paper proposes an energy-efficient WLAN device power control technique for streaming multimedia contents with the mobile IP storage. The proposed technique consists of a prefetch buffer input/output module, a WLAN device power control module, and a reconfigurable prefetch buffer module. Besides, it adaptively determines the size of the prefetch buffer according to a quality of the multimedia contents, and it dynamically controls the power mode of the WLAN device on the basis of power on-off operations while streaming the multimedia contents. We evaluate the performance of the proposed technique on a PXA270-based mobile device that employs the embedded linux 2.6.11, Intel iSCSI reference codes, and a WLAN device. Extensive experiments reveal that the proposed technique can save the energy consumption of the WLAN device up to 8.5 times with QVGA multimedia contents, as compared with no power control.

• Journal of IKEEE
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• v.25 no.3
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• pp.485-492
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• 2021

In this paper, we propose the development of a defect inspection system for polygonal containers. Embedded board consists of main part, communication part, input/output part, etc. The main unit is a main arithmetic unit, and the operating system that drives the embedded board is ported to control input/output for external communication, sensors and control. The input/output unit converts the electrical signals of the sensors installed in the field into digital and transmits them to the main module and plays the role of controlling the external stepper motor. The communication unit performs a role of setting an image capturing camera trigger and driving setting of the control device. The input/output unit converts the electrical signals of the control switches and sensors into digital and transmits them to the main module. In the input circuit for receiving the pulse input related to the operation mode, etc., a photocoupler is designed for each input port in order to minimize the interference of external noise. In order to objectively evaluate the accuracy of the development of the proposed polygonal container defect inspection system, comparison with other machine vision inspection systems is required, but it is impossible because there is currently no machine vision inspection system for polygonal containers. Therefore, by measuring the operation timing with an oscilloscope, it was confirmed that waveforms such as Test Time, One Angle Pulse Value, One Pulse Time, Camera Trigger Pulse, and BLU brightness control were accurately output.

• Journal of the Korean Society for Precision Engineering
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• v.16 no.2 s.95
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• pp.153-163
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• 1999

본 연구에서는 격자패널을 통한 소음전달을 감소시키기 위하여 외부 구조적 가진으로부터 유발된 경량 패널의 진동을 능동 제어하는 기법을 기술한다. 최적 되먹임제어기와 적응 앞먹임제어기가 결합된 혼합형 제어기가 진동제어기로 사용된다. 되먹임제어기는 주파수 영역의 모델규명법에 의해 추출된 다중 입/출력 패널진동계 모델에 대하여 LQG 최적기법을 이용하여 감쇠능을 향상시키도록 설계된다. 앞먹임제어기는 되먹임 궤환의 결합효과를 자동적으로 보정할 수 있는 제안된 학습법칙에 기초하여 패널의 잔류진동이 최소가 되도록 적응된다. 45.7${\times}$45.7${\times}$2.54 ${cm^3}$ 벌집형상의 고강도 패널, 4개의 관성형 구동기 및 이산신호처리장치에 의해 구현된 패널 진동계에 대한 능동제어 실험을 수행해 본 결과 600Hz 주파수대역에 대한 12dB 진동저감이 이루어 질 수 있었다.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.39 no.10
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• pp.1086-1097
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• 1990

The design of multivariable control systems using the Inverse Nyquist Array method is described in this paper. The INA is a simple design technique, which permits a designer to achieve his objectives for a controller specification in a step-by-step fashion using Gershgorin band and Ostrowski circle. The application to a multivariable system of CANDU nuclear power plant with 5 inputs, 8 outputs, and 24 state variables is reviewed and the simulation shows satisfactory results.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 1997.11a
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• pp.176-179
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• 1997

본 논문은 입/출력 관계가 불명확한 가전제품 제어에 인공신경회로망을 응용하여 지능형 제어기를 구현하는 방법에 관한 것이다. 다층신경회로망을 사용하고 Error Back Propagation 학습방법에 의하여 학습되도록 한다. 제어대상물에서 알 수 있는 정보는 입력값과 이에 대응하는 출력값 뿐이며 입력과 출력에 대한 관계를 수학적으로 모델링하기 어려운 경우이다. 인공신경회로망을 이용한 제어를 위하여 Neural Network Emulator(NNE)와 Neural Network Controller(NNC)가 개발되며 각 신경회로망의 초기하중백터는 제어대상에 오프라인 학습으로 결정하고, 자동조절과정에서 온라인 학습하여 새로운 대상제품 상황에 적응하도록 설계되었다. 제안된 지능형 제어시스템은 PC를 이용하여 실시스템에 적용하여 검토되었다.

• Journal of the Korean Institute of Telematics and Electronics
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• v.22 no.6
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• pp.89-96
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• 1985

A pole-placement control of discrete, deterministic, single-input single-output nonmini-mum phase systems is considered using a model reference type approach. The proposed pole-placement controller is designed in the parameter form to make the transfer function of the controller equal to that of the reference model with only single variable polynomial S(q-1). The proposed adaptive pole-placement controllr is designed with the true system para-meters by applying the adaptation method to the proposed pole-placement controller.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 1998.10a
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• pp.289-295
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• 1998

본 논문은 빠른 학습과 정확한 근사 능력을 갖는 새로운 CMAC 신경망 기반 퍼지 제어기르 제안한다. 제안한 CMAC 신경망 기반 퍼지 제어기(CBFLC)는 한 학습 주기 동안 전향 및 역전파 연산시 신경망내 유닛중 극히 일부분만이 활성화되어 학습에 참가하므로 학습 시간이 매우 빠르고, 비퍼지화 연산시 소속 함수의 중심값 뿐 아니라 폭을 동시에 고려하여 정확한 근사화를 얻는다. 제안한 퍼지 제어기내 입？출력 소속 함수의 중심값 및 폭 등의 구조적 파라메터들은 역전파 알고리즘에 의해 갱신된다. 제안한 CMAC 신경망 기반 퍼지 제어기를 트럭 후진 주차문제에 적용하여 근사화 능력 및 제어 성능면에서 여러 다른 퍼지 제어기들과 비교한다.

• Journal of the Korean Institute of Intelligent Systems
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• v.10 no.2
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• pp.138-145
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• 2000

A identification algorithm that finds optimal fuzzy membership functions and rule base to fuzzy model isproposed and a fuzzy controller is designed to get more accurate position and velocity control of wheeled mobile robot. This procedure that is composed of three steps has its own unique process at each step. The elements of output term set are increased at first step and then the rule base is varied according to increase of the elements. The adjusted system is in competition with system which doesn't include any increased elements. The adjusted system will be removed if the system lost. Otherwise, the control system is replaced with the adjusted system. After finished regulation of output term set and rule base, searching for input membership functions is processed with constraints and fine tuning of output membership functions is done.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.41 no.10
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• pp.805-812
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• 2013

The operational flight program(OFP) which has the functions of I/O processing with avionics, flight control logic calculation, fault diagnosis and redundancy mode is embedded in the flight control computer of Smart UAV. The OFP was developed in the environment of PowerPC 755 processor and VxWorks 5.5 real-time operating system. The OFP consists of memory access module, device I/O signal processing module and flight control logic module, and each module was designed to hierarchical structure. Memory access and signal processing modules were verified from bench test, and flight control logic module was verified from hardware-in-the-loop simulation(HILS) test, ground integration test, tethered test and flight test. This paper describes development environment, software structure, verification and management method of the OFP.

• Proceedings of the KIPE Conference
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• 2011.07a
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• pp.56-57
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• 2011

본 논문에서는 10kW급 3상 백투백 컨버터에 필요한 여러가지 제어 기술들을 살펴보고 시뮬레이션을 통해 제어 알고리즘의 타당성을 분석하며, 실제 하드웨어의 구성 및 계통연계 실험을 통해 입, 출력 전압, 전류 등 파형을 관찰하여 3상 백투백 컨버터의 타당성과 적정성을 알아본다.