• 전자공학회논문지B
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• 제30B권6호
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• pp.9-19
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• 1993

This paper presents a new concept of a reconfigurable manipulator system which adjusts its mechanical structure to suit the kinematic characteristics of a given task. A highly redundant manipulator designed as a general purpose manipulator needs to be reconfigured for a specific task. A general task can be decomposed of motion and force components with different control requirements: either gross motion control or fine motion control. Each of these task components are distributed to each part of the manipulator based on the control requirements and the structure of the manipulator. Through the reconfiguration, a redundant manipulator is decomposed into two local arms, and the kinematic characteristics of each local arm is adjusted to suit the assigned task. The reconfigured redundant manipulator has two local arms well-configured for the local tasks and cooperating in serial for a given task. This globally enhances the performance of a redundant manipulator to execute a specific task. The simulation results are shown.

• Journal of Power Electronics
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• 제9권2호
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• pp.320-333
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• 2009

A Photovoltaic (PV) system's power output varies with the change of climate. Frequency deviations, tie line voltage swings are caused by the varying PV power when large PV power from several PV systems is fed in the utility. In this paper, to overcome these problems, a simple coordinated control method for smoothing the variations of combined PV power from multiple PV systems is proposed. Here, output power command is formed in two steps: central and local. Fuzzy control is used to produce the central smoothing output power command considering insolation, variance of insolation and absolute average of frequency deviation. In local step, a simple coordination is kept between the central power command and the local power commands by producing a common tuning factor. Power converters are used to achieve the same output power as local command power employing PI control law for each of the PV generation systems. The proposed method is compared with the method where conventional Maximum Power Point Tracking (MPPT) control is used for each of the PV systems. Simulation results show that the proposed method is effective for smoothing the output power variations and feasible to reduce the frequency deviations of the power utility.

• 조명전기설비학회논문지
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• 제29권10호
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• pp.7-16
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• 2015

This study is intending to look into the status of the hitherto established local governments light pollution control ordinance, and to use the ordinance status as basic data of ordinance enactment related to light pollution in time of its establishment and revision in accordance with regional characteristics of each local government for the time to come. This study conducted this research in a total of 3-phase research methods. 1) This study inquired into the direction of the research plan through the theoretical consideration and analysis of the preceding researches after setting up research objectives according to research background and purpose. 2) Targeting 11 local governments which are enforcing the hitherto established ordinance, this study surveyed the status of the light pollution control ordinance. 3) This study carried out the contents analysis of the ordinance in the method of doing a comparative analysis of each provision of the ordinance according to local governments. It's hoped that on the basis of this research, local governments across the nation, which have not yet established the same ordinance, could minimize the damage to natural eco-system due to artificial lighting by promoting the urgent ordinance establishment suited for each region, and create human-oriented light environment by modifying various disorderly lighting environment.

• International Journal of Advanced Culture Technology
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• 제5권3호
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• pp.46-55
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• 2017

In recent years, public area CCTV has also begun to become more popular in the Korea. 2011, Korea's Ministry of Public Administration and Security has recommended that other local governments set up an integrated CCTV control center in each of their districts. The ministry was planning to make it compulsory for local governments to install an integrated CCTV control center by 2015. More than 570,000 public cameras are managed by public agencies and local government offices. Currently, the integrated CCTV control center is playing a very positive role in fighting crimes in the district particularly through its liaison with the district police. The CCTVs were operated by a several different agencies and departments in the district, resulting in considerable redundancy in public service, inefficiency and delays in response to crimes, and other emergency situations. Therefore, Control Center should be operated lawfully and efficiently. CCTV Control Center will be managed by three ways: (1) IT Governance through cooperation with civil areas (2) by regulated with proper laws and (3) managed by proper guideline and personal training.

• 대한전기학회논문지:전력기술부문A
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• 제48권7호
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• pp.815-823
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• 1999

This study considers an implementation of artificial neural networks to the receding horizon optimal control and is applications to power systems. The Generalized Backpropagation-Through-Time (GBTT) algorithm is presented to deal with a quadratic cost function defined in a finite-time horizon. A decentralized approach is used to control the complex global system with simpler local controllers that need only local information. A Neural network based Receding horizon Optimal Control (NROC) 1aw is derived for the local nonlinear systems. The proposed NROC scheme is implemented with two artificial neural networks, Identification Neural Network (IDNN) and Optimal Control Neural Network (OCNN). The proposed NROC is applied to a power system to improve the damping of the low-frequency oscillation. The simulation results show that the NROC based power system stabilizer performs well with good damping for different loading conditions and fault types.

• 한국기계가공학회지
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• 제10권6호
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• pp.39-45
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• 2011

Due to the introduction of the electronic control systems, agricultural machine is getting complicated with its special function. The complex electronics system increases difficulty of maintenances in the wiring harness system. The heavy wiring harness has some poor reliability and workability in the production line of manufacture also. So, in this study, some small local control modules are developed to complement the difficulties with the benefits of distributed control system. All of the local control modules are connected by using CAN communication. This system developed this study has the advantages of modification or alteration of wiring and local modules. All the sensors and actuators can be easily monitored and controlled by the main controller with the appropriate communication protocol made by in this study.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 합동 추계학술대회 논문집 정보 및 제어부문
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• pp.103-106
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• 2001

A new control method for a redundant manipulator is developed using a local optimal torque and null space joint velocity. By solving the dynamic control equations of the system, the local optimal torque is obtained. If only the local optimal torque is used for controlling the robot there is a possibility that the system is unstable. To eliminate the characteristics of instability during the movements, the control law with a null space concept is used. The new method is applied to the 3-DOF planar manipulator. The simulation results show the effectiveness of the proposed algorithm.

• 한국정보통신학회논문지
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• 제5권2호
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• pp.257-262
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• 2001

본 논문에서는 WDM 기반의 Local Network에서 가변길이 메시지를 수용하기 위한 스케줄링 프로토콜을 제안하였다. 제안된 프로토콜은 제어채널을 예약슬롯과 제어슬롯으로 나누어 제어 패킷의 충돌로 인한 액세스 지연시간을 최소화하였다. 즉, 전송할 메시지가 있는 노드는 빈 제어슬롯이 있으면 제어패킷을 제어슬롯에 전송하고 메시지를 전송한다. 그리고 메시지의 전송이 완료될 때까지 주기적으로 제어패킷을 전송하여 가변길이의 메시지를 전송할 수 있도록 하였다. 또한 빈 제어슬롯이 없는 경우에는 예약슬롯을 이용하여 가장 가까운 시간에 메시지를 전송하기 위한 데이터 슬롯을 미리 예약하여 제어패킷의 충돌로 인한 재전송 횟수를 감소시켰다. 제안된 알고리즘은 기존 프로토콜의 문제점을 해결하였으며 성능향상과 액세스지연시간의 감소 효과를 보였다.

• Radiation Oncology Journal
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• 제9권2호
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• pp.325-331
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• 1991

1979년부터 1988년까지 서울대학교병원 치료방사선과에서 방사선 치료를 받았던 Wilms씨 종양환자 28명의 치료성적을 분석하였다. 평균 추적관찰기간은 40개월이었다. 3년 국소 치유율 및 생존율은 각각 78.1$\%$와 67.4$\%$이었다. 연령에 따른 국소치유율의 차이는 없었다. Favorable histology 와 Unfavorable histology 유형의 국소치유율은 각각 83.3$\%$와 62.5$\%$이었다. Favorable histology유형의 II기와 III기 종양의 국소치유율 간에는 차이가 없었다($83.3\%\;vs100.0\%$). Unfavorable histology유형의 I/II기와 III기 종양의 국소치유율 간에는 유의한 차이가 있었다($83.3\%:0\%$). 임파절 침윤이 확인된 경우에서의 국소치유율은 불량하였다($50.0\%\;vs\;87.5\%$). 방사선치료를 수술후 10일 이후에 개시한 경우에서의 국소치유율과 수술 후 9일 이내에 개시한 경우에서의 국소치유율 간에는 유의한 차이가 있었다(p<0.05) . 따라서 방사선치료는 국소치유율을 향상시키는데 유용하였으나 수술적 절제가 불가능한 종양에 대하여는 치료방법의 강화가 필요하다고 판단된다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제11권1호
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• pp.272-287
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• 2017

This paper proposes new methods, named Derivative Code (DerivativeCode) and Derivative Code Pattern (DCP), for object recognition. The discriminative derivative code is used to capture the local relationship in the input image by concatenating binary results of the mathematical derivative value. Gabor based DerivativeCode is directly used to solve the palmprint recognition problem, which achieves a much better performance than the state-of-art results on the PolyU palmprint database. A new local pattern method, named Derivative Code Pattern (DCP), is further introduced to calculate the local pattern feature based on Dervativecode for object recognition. Similar to local binary pattern (LBP), DCP can be further combined with Gabor features and modeled by spatial histogram. To evaluate the performance of DCP and Gabor-DCP, we test them on the FERET and PolyU infrared face databases, and experimental results show that the proposed method achieves a better result than LBP and some state-of-the-arts.