• Title/Summary/Keyword: Recent trends

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RECENT TRENDS OF POWER ELECTRONIC INDUSTRY IN CHINA

  • Qian, Z.M.;He, X.
    • The Transactions of the Korean Institute of Power Electronics
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    • v.1 no.1
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    • pp.1-6
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    • 1996
  • Recent trends of the power electronic industry in China have been summarized in this paper. Based on the applications of the power electronic products in the chinese industries the production trends of power semiconductor devices, drives, power supplies, power electronic industry used in power systems in China have been briefly reviewed.

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Characteristics and Trends of Tropical Night Occurrence in South Korea for Recent 50 Years (1958-2007) (우리나라에서 최근 50년 (1958-2007)간 열대야 발생 특성 및 변화 경향)

  • Park, Woo-Sun;Suh, Myoung-Seok
    • Atmosphere
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    • v.21 no.4
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    • pp.361-371
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    • 2011
  • In this study, characteristics and trends of tropical night (TN) are investigated by using the KMA 14 observation data for the recent 50 years (1958-2007) over South Korea. The TN is defined as a day with a daily minimum temperature exceeds the absolute threshold temperature ($25^{\circ}C$), and the relative deviation from normal temperature, 95th percentile of all observed daily minimum temperature. Although the spatial distribution of TN occurrence depends on the choice of the definitions, the frequency of TN shows strong spatial and interannual variations with the minimum at high land area (Chupungnyeong and wet years) and maximum at southern coastal area and large city area (Jeju, Busan, Seoul, Daegu). Most of TN occurs in August (56%) and July (41%), and the duration date of TN is proportional to the frequency of TN without regard to the definition method. In general, increasing trends are found in the TN time series without regard to the analysis method, but the trends are clearly depending on the analysis period and geographic locations. Decreasing trends are prominent during the most of analysis period, especially until the mid of 1990, whereas strong increasing trends are found during recent 30 years (1988-2007), especially at Jeju, Ulsan, Daegu and Pohang. Also the severity of TN is significantly increased in recent years.

Transition of Fashion Trends and Fashion Colors in Recent 30 Years (최근 30년간의 패션 트렌드와 패션 컬러의 추이)

  • Lee, Kyung-Hee
    • Fashion & Textile Research Journal
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    • v.9 no.2
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    • pp.167-175
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    • 2007
  • Color is infinitely more complex and challenging when the human element is factored in. The nature of fashion presents additional issues that must be addressed, allowing for even greater possibilities. Fashion trends and fashion colors could be used as a starting point for investigating many possible applications in fashion industry. Modern fashion industry received various information from many medias. Fashion trends and fashion colors must be referred to primarily when planning fashion goods among so much information. In this study, changes in fashion trends and fashion colors from 1966 to 1995 were investigated. The results indicated fashion trends and fashion colors were involved with community, culture and economy. Furthermore, important characteristics of fashion trends were summarized. In recent 30 years fashion trends and fashion colors appeared practical fashion and natural color, amenity fashion and mild color. According to the fashion changes in sensitivity, the color change was evaluated. Fashion colors displayed changes from sign effect to symbol effect. Especially black changed from minus image to plus image made it important fashion color.

Research Trends of Cognitive Systems Engineering Approaches to Human Error and Accident Modelling in Complex Systems (복잡한 시스템에서의 인적오류 및 사고모형의 인지시스템공학적 연구의 동향)

  • Ham, Dong-Han
    • Journal of the Ergonomics Society of Korea
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    • v.30 no.1
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    • pp.41-53
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    • 2011
  • Objective: The purpose of this paper is to introduce new research trends of human error and accident modeling and to suggest future promising research directions in those areas. Background: Various methods and techniques have been developed to understand the nature of human errors, to classify them, to analyze their causes, to prevent their negative effects, and to use their concepts during design process. However, it has been reported that they are impractical and ineffective for modern complex systems, and new research approaches are needed to secure the safety of those systems. Method: Six different perspectives to study human error and system safety are explained, and then seven recent research trends are introduced in relation to the six perspectives. The implications of the new research trends and viable research directions based on them are discussed from a cognitive systems engineering point of view. Results: Traditional methods for analyzing human errors and identifying causes of accidents have critical limitations in complex systems, and recent research trends seem to provide some insights and clues for overcoming them. Conclusion: Recent research trends of human error and accident modeling emphasize different concepts and viewpoints, which include systems thinking, sociotechnical perspective, ecological modelling, system resilience, and safety culture. Application: The research topics explained in this paper will help researchers to establish future research programmes.

Digital Holographic Display Technology Trends (디지털 홀로그래픽 디스플레이 기술 동향)

  • Lim, Y.;Hong, K.;Park, M.;Kim, J.
    • Electronics and Telecommunications Trends
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    • v.32 no.5
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    • pp.30-38
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    • 2017
  • Digital holography is generally regarded as one of the most possible candidates for achieving a real 3D display system in that it can fully record and reconstruct the wave characteristics of light. In addition, 3D display systems based on digital holographic technology do not cause a vergence-accommodation mismatch problem. In this report, the recent trends in digital holographic display technology are described, and recent research results related to the fields of augmented reality and virtual reality are also briefly reported.

Recent Trends of Conformity Assessment Activity (적합성 평가 활동의 최근 동향)

  • Yang, Bo-Suk
    • 유체기계공업학회:학술대회논문집
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    • 2002.12a
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    • pp.459-464
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    • 2002
  • In this paper, the recent trends of conformity assessment activity which is carrying out at ISO is summarized. It is an increasing requirement of quality assurance systems that a company's engineers and technicians are able to demonstrate that they have the required level of knowledge and skill. This is particularly so since maintenance and Inspection activities are very operator dependent and those in authority have to place great reliance on the skill, experience, Judgement and integrity of the personnel involved.

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Recent Trends in High-Speed and Virtualized Optical Access Technologies (광액세스 고속화 및 가상화 기술 동향)

  • Chung, HwanSeok;Ra, YongWook;Park, Chansung;Lee, Joon Ki
    • Electronics and Telecommunications Trends
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    • v.35 no.5
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    • pp.57-68
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    • 2020
  • This paper reviews the recent trends in optical access technologies and their future directions. As the number of hyper-connected, ultra-low-latency, and hyper-realistic services increases, the wireless path has become shorter and the optical access network has become deeply penetrated into the end user. The optical access network continues to evolve through endless innovation via high-speed, ultra-low-latency, and abstraction/virtualization technologies.

Recent R&D Trends of Mobile FSO Technologies (모바일 자유공간 광전송(FSO) 기술 동향)

  • Yeo, C.I.;Heo, Y.S.;Ryu, J.H.;Lee, M.S.;Kang, H.S.;Park, S.W.;Kim, K.E.;Kim, S.C.
    • Electronics and Telecommunications Trends
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    • v.33 no.6
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    • pp.118-128
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    • 2018
  • With the massive increase in bandwidth for wireless communications, free space optical (FSO) communication has attracted significant interest owing to its outstanding strengths over conventional radio frequency wireless communication such as a wide bandwidth, unlicensed spectrum, low power consumption, small size, electromagnetic interference immunity, long-range propagation, and improved security. In recent years, FSO technology has been studied intensively for use in terrestrial and underwater autonomous and unmanned mobile systems, a rapidly growing application area, including robots, drones, unmanned aerial vehicles, autonomous vehicles, unmanned trains, and unmanned submarines. In this report, we review the recent trends and key technologies for the mobile FSO system, and introduce our drone-based mobile FSO system, which is currently under development.