• 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.

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

  • Yang, Bo-Suk
    • 유체기계공업학회:학술대회논문집
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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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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 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.

Analysis of the Recent Trend of National Background PM10 Concentrations over Korea, China, and Japan (한·중·일 PM10 국가 배경농도 최근 경향 분석)

  • Yang, Geum-Hee;Lee, Jong-Jae;Lyu, Young-Sook;Chang, Lim-Seok;Lim, Jae Hyun;Lee, Dong-Won;Kim, Sang-Kyun;Kim, Cheol-Hee
    • Journal of Korean Society for Atmospheric Environment
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    • v.32 no.4
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    • pp.360-371
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    • 2016
  • The goal of this research is to examine the recent decade-long (2000~2014) trends of national background concentrations over China, Japan, and Korea. Based on the Long-range Transboundary Air Pollutants in Northeast Asia (LTP) project, which is three-party collaboration project among three countries, we investigated the long-term trends of national background $PM_{10}$ concentrations in three countries over the recent 15 years, including the 2008 Beijing Olympic Game period. In accordance with the agreement among three countries, a total of 8 national background sites: three national background monitoring sites in China (2 sites in Dalian, and 1 in Xiamen), three sites in Korea (Ganghwa, Gosan, and Taean), and two sites in Japan (Oki and Rishiri), were chosen for the trend analysis. The results showed that Chinese background concentration recorded the highest level overall. However, the rapid declining recent trends of annual median ($50^{th}$-percentile) values were surprisingly detected since 2006 or 2007 in every site in China, with the most rapidly decreasing rate (- $18.6{\pm}10.3%$/year) over 2006~2007, and the second most rapidly decreasing rate (- $18.0{\pm}1.5%$/year) over 2007~2008. Based on the previous statistical literature, we concluded that this declining trends were due to the emission reduction of $PM_{10}$ concentrations in China for 2008 Beijing Olympic Game. In Korea, Ganghwa was also showing the decreasing trends over the recent years since 2006, which is also well accorded with the decreasing period of Chinese background concentrations. Taean also implied some impact of Beijing Olympic Game, showing small but detectable decreasing trends, while Gosan showed the increasing tendencies probably due to the near-urban influences. However, since 2012, most sites in both China and Korea showed strong increasing trends, undoubtedly implying the increasement of both emission in China and its long-range transport process toward Korea. Two sites in Japan, Oki and Rishiri recorded the lowest level of $PM_{10}$ level during whole period with the smallest deviations of measurements. Other discussions including the decade-long trends of $5^{th}$, $10^{th}$, $25^{th}$, $50^{th}$, $75^{th}$, $90^{th}$, $95^{th}$-percentiles of $PM_{10}$ background concentrations in three countries were also comparatively addressed here.