• Journal of the Korean Society of Marine Environment & Safety
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• v.25 no.1
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• pp.117-121
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• 2019

In this study, research and a demonstration for applying DC distribution systems to ships as an environmental and energy conservation solution in domestic and foreign countries were actively carried out. In order to apply a generator to a DC distribution system, a variable speed engine was used. Both engine speed and fuel consumption were reduced. In this paper, a DC generator for DC distribution was constructed using a diesel generator, a generator controller, a governor, and an AVR. A system configuration method for a generator, power quality test, and the power characteristics of a variable speed generator were analyzed. The voltage (250 - 440 VAC) and frequency (34 - 60 Hz) of the variable speed generator were set to 60 - 100 % of the rated value, and the engine was set to operate from 1100 - 1800 rpm. It was confirmed that the voltage, current, and frequency of the generator output fluctuated in a stable manner according to the power amount when changing the engine speed of the generator according to the load variation.

• Journal of IKEEE
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• v.17 no.4
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• pp.564-569
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• 2013

The current embedded devices are growing rapidly in the multi-core, and these demand fast boot time. But method of previous boot uses core only one. The method includes parallel techniques and modification of CPU Frequency policy. Parallel methods, after analyzing the Android boot process with analysis tool, applied to location where a lot of CPU operation. CPU Frequency policy is modified for high performance of core. The proposed method was applied to S5PV310 dual core and Exynos4412 quad core embedded system. As a result of the experiment, we found that the proposed method makes boot time fast about 20.71% and 31.34% in dual core and quad core environment as compared with the previous method.

• Journal of the Institute of Convergence Signal Processing
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• v.13 no.1
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• pp.56-62
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• 2012

This paper presents design and implementation of the speed controller for DC motor system using Embeded Target for TI C2000 DSP library in Matlab/Simulink is introduced. Speed controller are easily design and implemented by using the Matlab/Simulink program. Feedback of motor speed is processed through eZdsp F2812 AID converter using encoder and pulse meter as speed sensor. Real-time program of controller is drawn using Simulink and converted program code for speed control of P control, PID control and parameter estimation base adaptive control is downloaded into the TI eZdsp 2812 board. Experiments were carried out to examine validity of speed response for implemented controllers. And even if controlled plant becomes alteration studied controller design and implementation easily method.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.10a
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• pp.22-22
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• 2019

수국속(Hydrangea L.)은 APG IV분류체계에 따르면 국화군(Asterids), 층층나무목(Cornales), 수국과(Hydrangeaceae)에 속하는 식물로서 동아시아, 북아메리카 동부 지역을 중심으로 분포하며 전 세계에 23여종이 알려져 있다. 한국산 수국속은 Nakai가 H. hortensia var. acuminata의 분포를 기록함으로써 시작되었다. 이후 Nakai는 산수국을 H. acuminata로 재처리, 다시 H. serrata var. acuminata로 변경하였다. 한편 산수국은 분류학적 위치에 대한 이견이 있다. Wilson은 수국과 산수국을 가까운 유연관계를 가지는 독립된 분류군으로 분류하였지만, Makino는 산수국을 수국의 아종인 H. marcrophylla subsp. serrta로 기재하는 등 산수국과 수국의 동정과 계급설정에 혼란이 있는 가운데, 최근 천연물 hydrangenol을 활용한 건강기능식품 개발에서 사용가능 재료의 한계를 설정하기 위한 산수국과 수국에 대한 종 설정 연구도 요구되고 있다. 따라서 본 연구에서는 nrDNA ITS, trnL-F, trnC-ycf6의 3개 구간의 DNA sequence와 NCBI (National Center for Biotechnology Information)를 참고한 분자생물학적 분석결과와 외부형태학적 재검토 결과를 통하여 H. marcrophylla를 종(Species)으로서의 분류학적 위치 지지하며 또한 수국과 산수국을 가까운 유연관계를 가지는 독립된 분류군으로 분류한 의견을 지지하는 결과를 도출하였다. 향후 hydrangenol 활용의 기초정보로 활용되기를 기대한다.

• Proceedings of the KOSOMBE Conference
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• v.1997 no.11
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• pp.222-227
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• 1997

To diagnose cardiac arrhythmia owing to reentry mechanism, cardiac conduction system was modeled by modified Hidden Markov modeled by evaluated. First, simulation of transient conduction states and output waves were made with initially assumed parametric values of cardiac muscle repolariztion time, conduction velocity and its automaticity. The output was a series of onset time and the name of the wave. Parameters determined the rate of beating, lengths of wave intervals, rate of abnormal beats, and the like. Several parameter sets were found to simulate normal sinus rhythm, supraventricular /ventricular tachycardia, atrial /vetricular extrasystole, etc. Then, utilizing the estimation theorems of Hidden Markov Model, the best conduction path was estimated given the previous output. With this modified estimation method, close matching between the simulated conduction path and the estimated one was confirmed.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2021.04a
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• pp.34-34
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• 2021

과거 식물상에 대한 정보가 없었던 경기도 양주시 장흥면에 위치한 장군봉(425.0 m)의 식물상을 2020년 4월부터 10월까지 총 3회에 걸쳐 조사하였다. 본 조사에서 확인된 조사지 내 관속식물은 양치식물 8과 10속 9종 1변종 10분류군, 나자식물 3과 4속 6종 6분류군, 쌍자엽식물 62과 144속 198종 7아종 16변종 2품종 223분류군, 단자엽식물 6과 29속 38종 1아종 5변종 1픔종 45분류군으로 총 284분류군을 확인할 수 있었다. 장군봉 일대의 특산식물은 은사시나무 (Populus tomentiglandulosa T.B.Lee), 키버들 (Salix koriyanagi Kimura), 병꽃나무 (Weigela subsessilis (Nakai) L.H.Bailey), 백운산원추리 (Hemerocallis hakuunensis Nakai)의 4분류군이 분포하고 있었고 산림청에서 지정한 희귀식물로는 취약종 (VU) 등급의 주목 (Taxus cuspidata Siebold & Zucc.) 1분류군이 확인되었다. 느릅나무 (Ulmus davidiana var. japonica (Rehder) Nakai)를 포함하여 I등급 10종, 함박꽃나무 (Magnolia sieboldii K.Koch) 등 II등급 4종, 병조희풀 (Clematis heracleifolia DC.) 등 III등급 8종, IV등급에 해당하는 바위말발도리 (Deutzia grandiflora var. baroniana Diels) 등 총 25종이 식물구계학적특정종에 속했다. 침입외래식물은 미국자리공 (Phytolacca americana L.), 유럽점나도나물 (Cerastium glomeratum Thuill.), 청비름 (Amaranthus viridis L.) 등 20분류군을 확인할 수 있었고, 생태계교란야생식물인 환삼덩굴 (Humulus japonicus Sieboid & Zucc.), 돼지풀 (Ambrosia artemisiifolia L.), 단풍잎돼지풀 (Ambrosia trifida L.), 미국쑥부쟁이 (Aster pilosus Willd.)의 4분류군이 확인되었다.

• Journal of Korea Game Society
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• v.9 no.2
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• pp.115-123
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• 2009

This paper proposes an algorithm to improve the performance of the spatial partitioning method for flocking behaviors. The core concept is to improve the performance by using the fact that even if a moving entity, boid in flock continuously changes its direction and position, its k-nearest neighbors, kNN to effect on decision of the next direction is not changed frequently. From the previous kNN, the method to check whether new kNN is changed or not is proposed in this paper and then the correctness of the proposed method is proved by two theorems. The proposed algorithm was implemented and its performance was compared with the conventional spatial partitioning method. The results of the comparison show that the proposed algorithm outperforms the conventional one by about 30% with respect to the number of frames per a second.

• Journal of Korea Multimedia Society
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• v.11 no.5
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• pp.588-596
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• 2008

For the patients' privacy, secure access control of medical images is essentially necessary. In this paper, two types of Region of Interest (ROI)-based selective encryption schemes are proposed, which concentrate on the security of crucial parts in medical images. The first scheme randomly inverts the most significant bits of ROI coefficients in several high frequency subbands in the transform domain, which only incurs little loss on compression efficiency. The second scheme employs a symmetric key encryption to encrypt selectively the ROI data in the final code-stream, which provides sufficient confidentiality. Both of two schemes are backward compatible so as to ensure a standard bitstream compliant decoder so the encrypted images can be reconstructed without any crash.

• Journal of Advanced Navigation Technology
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• v.15 no.1
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• pp.130-139
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• 2011

In this paper, vehicle tracking algorithm using hue transformation in HIS color model is proposed. the proposed algorithm is installed on the road of the two horizontal virtual data sampling lines. The difference images are detected between the frame and the frame, respectively and also detected in the vehicle by using the hue color distribution to determine identity and lane changes. To examine the effectiveness of proposed algorithm, identification and velocity measurement for driving vehicle are evaluated. this evaluated results is shown by hue data of vehicle passing of two virtual data sample lines, and the velocity measurement for driving vehicle is less than 0.4% comparing with existing vehicle speed meter system.

• Proceedings of the Korea Inteligent Information System Society Conference
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• 2007.11a
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• pp.556-563
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• 2007

국제 물동량의 증가로 인한 해상운송의 활성화는 시장 참여자들의 경쟁 심화로 이어지고 있다. 따라서 해상운송의 효율성 향상을 통한 경쟁력 강화의 필요성이 높아지고 있다. 특히 한국의 경우에는 자동차 수출입 물동량의 증가로 인한 자동차 운반선사(Car Carriers)의 효율적인 운송계획의 중요성이 강조되고 있다. 이에 본 연구에서는 자동차 운반선의 현황분석을 통한 운송계획의 문제점을 분석하고, 이를 해결할 수 있는 자동차 운반선 해상운송계획 지원 시스템을 개발한다. 이는 자동차 운반선에 관한 해상운송계획 과정을 체계화함으로써 계획의 수립 속도 및 질적 수준을 향상시키고, 계획의 체계적인 관리(수정, 변경 등)를 가능케 함으로써 사용자가 보다 나은 의사결정을 내릴 수 있도록 하기 위함이다. 한편 자동차 운반선의 해상운송계획 과정에서 해상운송과 자동차 화물의 특성에 의해 발생되는 다양한 예외상황들을 고려할 수 있도록 하기 위해 IP(Integer Programming) 모형을 사용하여 이익을 최대로 하는 또는 비용을 최소로 하는 최적의 안을 생성하고, 계획 수립 이후에 발생하는 변경사항들을 실무자가 효율적으로 수정할 수 있도록 해상운송계획 지원 시스템을 개발한다.