• 제목/요약/키워드: 통신량

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A Study on the Effective VTS Communications Analysis by the Method of VCDF in Busan Port (VCDF 방식을 통한 효율적인 VTS 통신 데이터 분석에 관한 연구 - 부산항을 대상으로 -)

  • Kim, Bong-Hyun;Park, Young-Soo
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.22 no.4
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    • pp.311-318
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    • 2016
  • The VTS concept was located as a principal methods of maritime safety administration in world's major harbors and expected to become the pivotal role for the future of the maritime and harbor society with e-Navigation epoch. If recent limelight concept of big-data has been included in aspect of information gathering and analysis with various studies, it's required advanced studies to improve the information analysis capability and application range of the data that can be mining by the VTS. In this study, contrast to other studies that aimed quantitative analysis as communication number, it can be mining the time information and each of the communication VTS for the target vessel, including qualitative analysis, such as the purpose or the type of communication. This comparison across multiple items of the collected information, and presenting the VTS data mining model (VCDF) that can be analyzed for the purpose of analyzing way, type and number of communication by ship's type, also number of violations through VTS communication. First, In Busan port case, it shows frequently information service and shows frequently communicating with particular types of vessels. Second, Passive VTS carried out notwithstanding many kinds of traffic violations due to communication congestion. This arranged information can be used as data for the analysis, as possible the level of traffic for VTSO situational awareness, which pointed to the 'workloads' in 'IALA Guideline' and could be used as a database for future research of e-Navigation.

A Dual Module DC-DC Converter with Six switches for High Power Capacity (대용량 정류기용 Dual Module DC-DC 컨버터 Topology 연구)

  • 계문호;김성철;조기연;김은수
    • Proceedings of the KIPE Conference
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    • 1997.07a
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    • pp.276-279
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    • 1997
  • 본 논문은 통신용전원장치와 같은 대용량의 DC 전원 장치에 적용하기 위하여 3상용 6 Switch로 구성된 Bridge로써 대용량 DC-DC converter에 적합한 Topology에 관한 것이다. 기본 동작은 기존의 Phase shifted ZVS PWM 방식을 사용하며, Bridge의 바깥쪽 양쪽암의 펄스폭을 제어하는데, 같은 펄스를 동시에 주는 방식과 각각 별도로 제어하는 방식, 두암의 위상을 지연시키는 방식에 관하여 연구하였다. 제안된 Topology들은 컴퓨터 시뮬레이션을 수행하여 그 동작특성을 확인하였고, 대용량에 적용할 수 있음을 확인하였다. 장치의 용량은 출력 500[A]/30[V] 회로를 구성하여 각각의 경우에 대하여 컴퓨터 시뮬레이션 결과를 제시하였다.

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$ZrO_2$-$TiO_2$ 세라믹의 $MoO_2$ 함유량과 소결온도가 유전특성에 미치는 영향

  • Lee, Sang-Seok;Lee, Seok-Jin;Lee, Chang-Hwa;Choe, Tae-Gu
    • ETRI Journal
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    • v.14 no.4
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    • pp.210-216
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    • 1992
  • 불요 전자파 제거용 필터의 유전체로 사용되는 Zirconium Titanate 세라믹 유전체에서 $MoO_2$ 함유량과 소결온도에 변화를 주어 이들이 유전특성에 미치는 영향에 대하여 검토하였다. 일반적으로 $MoO_2$ 함유량보다는 소결온도의 변화가 유전률, 품질계수 및 소결밀도 등에 더 큰 영향을 주었으며, 정전용량의 온도계수 측면에서는 $MoO_2$ 함유량을 제어하여0ppm$^\{circ}C$근처로 이동시켜 상당히 안정된 온도 특성으로 개선할 수 있었다.

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Computation cost reduction method of EBCOT using upper subband search information in the wavelet domain (웨이블릿 영역에서의 상위 부대역 탐색정보를 이용한 EBCOT의 연산량 감소 방법)

  • Choi, Hyun-Jun;Paik, Yaeung-Min;Seo, Young-Ho;Kim, Dong-Wook
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.13 no.8
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    • pp.1497-1504
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    • 2009
  • This Paper Propose a method to reduce the calculation time in JPEG2000. That is, if a coefficient is estimate a upper-level subband and its descendents skip the scan process. There is a trade-off relationship between the calculation time and the image quality or the amount of output data, the calculation time and the amount of output data decreases, but the image degradation increases. The experimental results showed that in calculation time was 35% in average, which means that ls ge ses. The ein calculation time and output data can be obtls ed with a cost of an acceptlble image quality degradation.

Momentum and Average Force applied to Golf Ballm (골프공에 가해진 운동량과 평균력)

  • Shin, Kwang-Seong;Rhee, Yang-Won
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2011.05a
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    • pp.157-158
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    • 2011
  • Golf clubs hit the ball, and golf balls fly with great speed and long distances due to the conflict. In this paper, the size of the momentum after collision of golf clubs and golf balls should seek. Also, the collision times and average force that served of golf clubs and golf balls are obtained. We know that the impulse acting body is equals the change in momentum of a body. And you can see the average force is constant force that the actual strength of a body to give the same impulse instead of force changing by the hour.

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Sums and Weighted Sums of the Score functions of Locally Optimum Rank Detectors (국소 최적 순위 검파기의 점수 함수의 합과 가중합)

  • 배진수;박현경;송익호
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.27 no.6A
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    • pp.517-523
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    • 2002
  • The closed from of sums and weighted sums of the score functions of the locally optimum rank detectors are obtained in this paper. When we consider the asymptotic performance characteristics of a detector based on rank and sign statistics, the sums and weighted sums of the score functions have to be prepared. The efficacy of a detector can be obtained from the sums and weighted sums of the score functions. Score functions based on rank statistics, as well as those based on magnitude rank and sign statistics, have also been considered, which includes most score functions presented in the literature.

Optimization of Economic Load Dispatch Problem Using Linearly Approximated Smooth Fuel Cost Function (선형 근사 평활 발전 비용함수를 이용한 경제급전 문제의 최적화)

  • Lee, Sang-Un
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.14 no.3
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    • pp.191-198
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    • 2014
  • This paper proposes a simple linear function approximation method to solve an economic load dispatch problem with complex non-smooth generating cost function. This algorithm approximates a non-smooth power cost function to a linear approximate function and subsequently shuts down a generator with the highest operating cost and reduces the power of generator with more generating cost in order to balance the generating power and demands. When applied to the most prevalent benchmark economic load dispatch cases, the proposed algorithm is found to dramatically reduce the power cost than does heuristic algorithm. Moreover, it has successfully obtained results similar to those obtained through a quadratic approximate function method.

Parity Bits Request Estimation Using Motion Information Feedback for Fast Distributed Video Decoding (고속 분산 비디오 복호화를 위한 움직임 정보 피드백을 이용한 패리티 비트 요구량 예측 기법)

  • Kim, Man-jae;Choi, Haechul;Kim, Jin-soo
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2012.10a
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    • pp.107-108
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    • 2012
  • For low complexity encoder, the parity bit transmission through a feedback channel is an essential part of DVC. But feedback channel-based parity bit control is a major cause for the high decoding time latency. In this paper, we propose a fast distributed video decoding by parity bit request estimation using rate-distortion model. Through computer simulations, it is shown that the proposed method can achieve complexity reduction compared to other methods.

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Matrix Pencil Method Using Fourth-order Statistic (4차 통계량을 이용한 Matrix Pencil Method)

  • Jang Woo-Jin;Wang Yi-Su;Zhou Wei-Wei;Koh Jin-Hwan
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.31 no.6C
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    • pp.629-636
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    • 2006
  • In array signal processing, high order statistics can be used to estimate parameters from signal of sums of complex exponential. In this paper, we derive two types of direction finding algorithms which use the fourth-order cumulant and moment of the received array data. Since the fourth order cumulant can suppress the Gaussian noise, the response of MPM has better noise immunity than the conventional approaches. The performance of each method in regard to the probability of resolution and SNR in the presence of the Gaussian noise is investigated. As a result, the proposed method applied to the fourth-order statistic can find DOA more correctly in the presence of the Gaussian noise.

A Geometric Derivation of the Craig Representation for the Two-Dimensional Gaussian Q-Function (이변량 가우시안 Q-함수의 Craig 표현에 대한 기하학적인 유도)

  • Park, Seung-Keun;Lee, Il-Kyoo
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.36 no.4A
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    • pp.325-328
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    • 2011
  • In this paper, we present a new and simple derivation of the Craig representation for the two-dimensional (2-D) Gaussian Q-function in the viewpoint of geometry. The geometric derivation also leads to an alternative Craig form for the 2-D Gaussian Q-function. The derived Craig form is newly obtained from the geometry of two wedge-shaped regions generated by the rotation of Cartesian coordinates over two correlated Gaussian noises. The presented Craig form can play a important role in computing the probability represented by the 2-D Gaussian Q-function.