• Title/Summary/Keyword: 동조성

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Analysis of the Synchronization between Global Dry Bulk Market and Chinese Container Market (글로벌 건화물 운임시장과 중국 컨테이너 운임시장 간의 동조성 분석)

  • Kim, Hyun-Sok;Chang, Myung-Hee
    • Journal of Navigation and Port Research
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    • v.41 no.1
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    • pp.25-32
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    • 2017
  • The purpose of this investigation is to analyze the synchronization between the representative global freight index, the Baltic Dry bulk Index (BDI) and the China Container Freight Index (CCFI) with monthly data from 2000 to 2016. Using the non-stationarity of the business cycle that is able to include common trends, we employ the Engle-Granger 2 stage co-integration test and found no synchronization. On the contrary, we additionally estimated the causality between the markets and revealed the causality, which implies that the Chinese economy has a significant effect on the global market. The results of this empirical analysis demonstrate that the CCFI of China is appropriate for analyzing the shipping industry. In practice, this means that it is more appropriate to include CCFI in the global market outlook than use it as a substitute for the global freight rate index, the BDI. This is a case study of the synchronization of the economic fluctuations of the shipping industry. It suggests that the economic fluctuations of China need to be considered in the unstable global market forecast. In particular, this case applies to the fluctuations in the shipping industry synchronism and provides important results in scientific terms.

An Auto-tuning of PI Controller using Microprocessor (마이크로 프로세스를 이용한 PI 제어기 설계)

  • Jeong, Soon-Hyun;Kwon, Soon-Kul;Suh, Ki-Young;Lee, Soo-Heum;Kim, Young-Mun
    • Proceedings of the KIEE Conference
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    • 2002.06a
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    • pp.25-28
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    • 2002
  • 본 논문은 마이크로 프로세스로 처리되는 여러 제어장치들 중에서 PI제어기의 최적 자동동조에 관한 개선된 방법을 제안하고자 한다. 이 방법은 Relay 자동동조 법으로서 이를 마이크로 프로세스에 응용하여 제어대상에 최적의 PI계수를 입력하게된다. 이를 위해 먼저 Computer와 DSP사이에 통신이 가능하도록 RS-232를 설치하고, 컴퓨터의 제어신호에 따라 모터의 속도가 Relay와 PI제어기에 의해 목표값에 도달할 수 있도록 설계하였다. 내부적으로 사용된 Relay 동조방식은 Relay로 제어대상의 출력을 강제로 진등시켜서 출력의 진폭과 주기를 이용하여 PI 계수를 조정하고 제어기의 입력값으로 선택된다. Relay동조 법은 동조과정이 간단하여 동조 방식의 구현이 쉽다. 또 위상여유를 고려하여 제어기의 계수를 조정하기 때문에 시스템의 견실성을 향상시킬 수 있을 뿐 아니라, 비례 제어만으로 임계 진동을 하지 않는 시스템의 경우에도 사용할 수 있고, 원점에 극점이 있는 경우에도 적용할 수 있어서 기존의 제어방식이 가지는 제약성의 한계를 극복할 수 있어서 적용성이 우수하다.

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Personal Value Determinants of Fashion Orientation: Materialism and Consumer Conformity (패션성향에 영향을 미치는 개인가치 결정요인: 물질주의와 소비자 동조성을 중심으로)

  • 박혜정;전경숙
    • Journal of the Korean Society of Clothing and Textiles
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    • v.28 no.910
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    • pp.1243-1252
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    • 2004
  • The purpose of this study was to identify the impact of personal values on fashion orientation. As personal values, this study adopted materialism and consumer conformity. Data were gathered by surveying university students living in Seoul metropolitan area using convenient sampling, and 325 questionnaires were used in the statistical analysis. In analyzing data, confirmatory factor analysis and path analysis were conducted using structural equation modeling. Confirmatory factor analysis revealed that fashion orientation has three factors such as fashion leadership, fashion interest, and importance of being well dressed. Path analysis showed that centrality factor of materialism spurred all three factors of fashion orientation and that happiness factor of materialism gave rise to importance of being well dressed of fashion orientation. Informational conformity also significantly increased all three factors of fashion orientation.

Digital Image Watermarking Using Perceptually Tuned Characteristic and Stochastic Model Based on Multiwavelet Transform (멀티웨이브릿변환 영역에서 지각적 동조 특성과 통계적 모델을 이용한 디지털 영상 워터마킹)

  • 황의창;윤재식;유상욱;문광석;박남천;권기룡
    • Proceedings of the Korea Institute of Convergence Signal Processing
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    • 2003.06a
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    • pp.54-57
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    • 2003
  • 본 논문에서는 멀티웨이브릿 변환영역에서 통계적 모델과 지각적 동조특성을 이용한 적응적 디지털 워터마킹 기법을 제안한다. 워터마크는 4레벨로 분해된 멀티웨이브릿 변환영역에서 최저주파 영역과 최고주파 대역들을 제외한 중간 및 고주파 영역에, 인간 시각 시스템(human visual model BWS)을 이용한 JND(just noticeable difference) 특성과 NVF(noise visibility function)를 이용한 통계적 특성을 기반으로 정상상태 가우시안 모델과 비정상상태 가우시안 모델에 따라 지각적 동조 특성을 이용하여 적응적으로 삽입된다. 실험 결과 제안한 방법에서 에지나 텍스쳐 영역에 더 강하게 삽입할 수 있었고, 평탄영역에서 보다 적응적으로 은닉할 수 있었으며 정상상태 가우시안 모델에서 지각적 동조특성을 이용한 방법이 더 우수한 비가시성과 강인성을 확인하였다.

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Research on Emotional Convergence Technology based on Non Contact Sensing and Social Interaction. (비접촉 센싱 기술과 사회적 상호작용에 따른 감성융합기술 연구)

  • Hwang, Sung Teac;Whang, Mincheol
    • Journal of the Korea Convergence Society
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    • v.8 no.6
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    • pp.163-170
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    • 2017
  • In this paper want to recognize competition and cooperation as a non-contact sensing method among the social emotion that are caused by interaction. Experiments were conducted in a pattern matching task divided into competition and cooperation situations. Data collection was performed by extracting the micro-movement data of 15Hz component from the upper body image. We compared and analyzed the amount and the variation and synchronization. As a result, Amount and variation are bigger in competition than cooperation. Synchronization was higher in cooperation than competition. This can be seen as the difference between two people trying to win when they are in competition and trying to breathe each other in cooperation. This study is significant in confirming the possibility of competition and cooperation through non contact sensing method based on physiological response.

Slow Sync Image Synthesis from Short Exposure Flash Smartphone Images (단노출 플래시 스마트폰 영상에서 저속 동조 영상 생성)

  • Lee, Jonghyeop;Cho, Sunghyun;Lee, Seungyong
    • Journal of the Korea Computer Graphics Society
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    • v.27 no.3
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    • pp.1-11
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    • 2021
  • Slow sync is a photography technique where a user takes an image with long exposure and a camera flash to enlighten the foreground and background. Unlike short exposure with flash and long exposure without flash, slow sync guarantees the bright foreground and background in the dim environment. However, taking a slow sync image with a smartphone is difficult because the smartphone camera has continuous and weak flash and can not turn on flash if the exposure time is long. This paper proposes a deep learning method that input is a short exposure flash image and output is a slow sync image. We present a deep learning network with a weight map for spatially varying enlightenment. We also propose a dataset that consists of smartphone short exposure flash images and slow sync images for supervised learning. We utilize the linearity of a RAW image to synthesize a slow sync image from short exposure flash and long exposure no-flash images. Experimental results show that our method trained with our dataset synthesizes slow sync images effectively.

A Study of DC Motor Speed Control By tms-320C32 Based (TMS-320C32기반에 의한 DC 모터 속도제어의 연구)

  • Jeong, S.H.;Kwon, S.M.;Cheon, J.M.;Lee, S.H.
    • Proceedings of the KIEE Conference
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    • 2003.07d
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    • pp.2218-2220
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    • 2003
  • 현대 산업현장에서 80%이상 사용되는 PID(proportional integral derivative) 제어기는 제어성, 적응성, 제어이득 조정 등의 특정이 있어나 제어 대상에 대한 PID 제어 계수를 경험적 방법인 수동으로 동조해야하는 문제점이 있다. 이를 개선하기 위해 본 논문에서 PID제어기의 최적 자동동조를 위한 릴레이 동조 방법을 제안한다. 기존의 한계감도법과 과도응답 법으로 초기계수를 결정하는 방법보다 유연성과 적용성이 높고, 이를 마이크로프로세서(DSP : TMS-320C32)에 적용하여 소프트웨어적으로 릴레이의 기능이 이루어지도록 설계했다. 이는 Ziegler-Nichols 계수조정법이 갖는 적용대상의 제약성을 극복한 방법이며, 릴레이에 의해 출력을 강제 진동시키고 출력의 진폭과 주기를 이용하여 PID 계수를 조정하고, 또 상대안정성의 척도인 위상여유를 고려하므로 시스템의 상대안정성과 견실성을 향상시킬 수 있음을 확인하였다.

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Optimum Tuning of PID-PD Controller considering Robust Stability and Sensor Noise Insensitivity (센서 잡음 저감도 및 안정-강인성을 고려한 PID-PD 제어기의 최적 동조)

  • Kim, Chang-Hyun;Lim, Dong-Kyun;Suh, Byung-Suhl
    • Journal of the Institute of Electronics Engineers of Korea SC
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    • v.44 no.1
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    • pp.19-24
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    • 2007
  • In this paper, we propose a tuning method of PID-PD controller to satisfy design specifications in frequency domain as well as time domain. The proposed tuning method of PID-PD controller consists of the convex set of PID and PI-PD controller. PID-PD controller controls the closed-loop response to be located between the step responses, and Bode magnitudes of closed-loop transfer functions controlled by PID and PI-PD controller. The controller is designed by the optimum tuning method to minimize the proposed specific cost function subject to sensor noise insensitivity and robust stability. Its effectiveness is examined by the case study and analysis.