• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2006년도 International Symposium on GPS/GNSS Vol.1
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• pp.285-290
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• 2006

This paper presents an adaptive neural network based controller and its application to Dynamic Positioning (DP) control system of ship. The proposed neural network based controller is developed for station-keeping and low-speed maneuvering control of ship. At first, the DP system configuration is described. And then, to validate the proposed DP system, computer simulations of station-keeping and low-speed maneuvering performance of a multi-purpose supply ship are presented under the influence of measurement noise, external disturbances such as sea current, wave, and wind. The simulations have shown the feasibility of the DP system in various maneuvering situations.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2004년도 추계학술대회 논문집
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• pp.1128-1131
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• 2004

SFF(solid freeform fabrication) is another name of RP(rapid prototyping). The SFFS for office type wishes to develop system that can produce small object such as hand phone, cup, accessory etc. with high speed, and also intend suitable system in office environment by compact design, and buy easily by inexpensive price. As can manufacture high speed in existent SFF process technology, representative process that have competitive power in price is 3DP (three dimensional printing) technology. The 3DP technology is way to have general two dimensional printing technology and prints to three dimension, is technology that make three-dimensional solid freeform that want binder doing jetting selectively on powder through printer head. We designed and manufactured SFFS for office based on 3DP process technology design and manufactured, and composed head system so that use 3 printer heads at the same time to improve the fabrication speed of system. We used printer head of INCJET company and cartridge used HP45 series model who can buy easily in general city. And we directly fabricated three dimensional solid freeform using developed SFFS for office type.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 학술대회 논문집 정보 및 제어부문
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• pp.249-251
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• 2004

In this paper, we analyses transmission performance of interleaving for cipher communication in TDMA STD DP mode of aerial tactical communication link. In LINK16 link we present about transmission architecture of STD DP mode and study an effect of interleaving, the capability of crypto synchronization pattern, and a quality of degraded effect of transmission communication during crypto communication.

• 제어로봇시스템학회논문지
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• 제8권4호
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• pp.281-287
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• 2002

This paper investigates on the feasibility of fuzzy logic control for networked control systems. In order to evaluate its feasibility, a networked control system for motor speed control is implemented on a Profibus-DP network. The NCS consists of several inde-pendent, but interacting processes running on two separate stations. By using this NCS, the network-induced delay is analyzed to find the cause and effect of the delay. Furthermore, in order to prove the feasibility, the fuzzy logic controller's performance is compared with those of conventional PID controllers. Based on the experimental results, the fuzzy logic controller can be a viable choice far NCS due to its robustness against parameter uncertainty.

• ETRI Journal
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• 제43권6호
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• pp.978-990
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• 2021

This article presents techniques for improved estimation of symbol timing offset (STO) and carrier frequency offset (CFO) for dual-polarization (DP) orthogonal frequency division multiplex (DP-OFDM) systems. Recently, quaternion multiple-input multiple-output OFDM has been proposed for high spectral efficiency communication systems, which can flexibly explore different types of diversities such as space, time, frequency, and polarization. This article focuses on synchronization techniques for DP-OFDM systems using a cyclic prefix, where the application of quaternion algebra leads to new improved estimators. Simulations performed for DP system methods show faster reduction of STO estimator variance with a double-slope line in the logvariance line versus signal-to-noise ratio (SNR) plot compared with singlepolarization (SP) counterparts, and simulations for CFO estimates show a 3-dB gain of DP over SP estimates for same SNR values defined, respectively, for quaternion-valued or complex-valued signals. Cramer-Rao bounds for STO and CFO are derived for the synchronization methods, correlating with the observed gains of DP over SP OFDM systems.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2022년도 추계학술대회
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• pp.188-188
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• 2022

선박의 운용 효율을 높일 수 있는 방법인 무인 운용체계는 근래에 많은 관심을 받고 연구되어 왔다. 특히 무인수상선과 무인수중체의(USV-AUV)의 복합 운용 분야는 그 동안 어려움이 있었던 심해저 탐사 및 특수 임무 활용에 용이하여 많은 연구가 수행되고 있다. 본 연구에서는 쌍동선 형태인 무인수상선이 모선이 되고 무인수중체가 결합하여 충전하고 다시 진수하여 원거리 및 심해저 조건에서 무인수중체가 운용 가능하도록 하는 시스템의 일부인 USV-AUV의 docking을 위한 DP 시스템을 개발하고 선박해양플랜트연구소 해양공학수조에서 모형시험을 통해 이를 검증하였다. 또한, 실제 제작된 무인쌍동선과 추진 시스템을 활용하여 모형시험을 통해 검증한 DP 알고리즘을 적용하여 화성 제부도 앞바다에서 실선 DP 테스트를 수행하였다. 실 해역에서의 DP 시스템 테스트는 정확한 환경 조건의 계측 및 구현이 어려워 모형시험과 같은 정량적인 평가는 어렵지만, 정성적으로 DP 시스템이 작동하는 것을 확인할 수 있었다.

• 한국음향학회지
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• 제14권3호
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• pp.97-104
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• 1995

본 논문은 음성 다이얼링 시스템 구현을 위한 연속 숫자음 인식에 관한 연구로써, 구문 분석을 이용한 One-Stage DP에 의한 음성 인식 방법을 제안하다. 인식 실험을 위해 우선 구간 구분화 알고리즘을 이용하여 DMS (Dynamic Multi-SEction) 모델을 만들며, 제안된 구문 분석을 이용한 One-Stage DP 방법으로 실험 대ㅛ상의 연속 숫자음 데이터를 인식하게 하였다. 본 연구에서는 8명의 ㅣ남성 화자에 의해 2-3번 발음도니 21종의 7자리의 연속 숫자음이 사용되었고, 기존의 One-Stage DP와 제안된 구문 분석을 이용한 One-Stage DP 음성 인식 알고리즘을 사용해서 화자 종속과 화자 독립 실험을 실험실 환경에서 수행하였다. 인식 실험 결과, 기존의 방법보다 제안된 방법이 인식률이 좋은 것으로 나타났으며, 제안된 방법에서는 화자 종속과 화자 독립 실험에서 각각 약 91.7%, 89.7%로 나타났다.

• 전기전자학회논문지
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• 제4권2호
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• pp.266-273
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• 2000

OCXO (Oven Controlled X-tal Oscillator)의 주파수 모델이 holdover 알고리즘을 DP-PLL (Digital Processing-Phase Locked Loop) 시스템에 적용하기 위해 제안되었다. 이 모델은 온도와 OCXO의 노화에 따라 2차 다항식으로 간단하게 표현된다. 모델 변수들은 LSM (Least Squared Method)을 적용한 실험 데이터로부터 얻어진다. holdover 알고리즘은 다른 실험 데이터를 사용한 동일한 모델로 모의실험 할 수 있다.

• International Journal of Fuzzy Logic and Intelligent Systems
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• 제5권4호
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• pp.333-338
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• 2005

This paper presents the target object search algorithm under Dynamic Programming (DP) in the Tree-type maze. We organized an experimental environment with the concatenation of Y-shape diverged way, small mobile robot, and a target object. By the principle of optimality, the backbone of DP, an agent recognizes that a given whole problem can be solved whether the values of the best solution of certain ancillary problem can be determined according to the principle of optimality. In experiment, we used two different control algorithms: a left-handed method and DP. Finally we verified the efficiency of DP in the practical application using our real robot.

• 한국해양공학회지
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• 제33권2호
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• pp.99-105
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• 2019

Unlike typical a dynamic positioning (DP) system, a DP-assisted mooring system must determine a set point (SP) that can ensure a mooring tension safety range to prevent an excessive increase in mooring tension. In this paper, a new algorithm for determining the SP is suggested in order to reduce the tension on all the mooring lines. To determine the SP, a working area around the vessel is represented by a rectangular grid. Thus, the size of the grid area is limited considering the offset of a vessel with a mooring system. At each grid's nodes, the resultant tension from all the mooring lines is estimated using the time history of the tension and vessel's position. The results of static analyses for each grid position are used to estimate the global tension. Consequently, the SP is automatically selected as a position satisfying criterion for minimizing the total tension. In order to validate the suggested algorithm, a motion simulation with the control system in the time domain and a discussion of the results are presented.