• Title/Summary/Keyword: Next generation ITS

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The Present State of Wind Turbine Condition Monitoring System (풍력 터빈 상태 감시 시스템 현황)

  • Clark, Timothy J.;Bauer, Richard F.;Rasmussen, James R.;Jeong, J.H.;Lee, B.J.;Lee, C.M.
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2005.11a
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    • pp.92-97
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    • 2005
  • The $9 billion US global wind energy market is experiencing dramatic growth with installed generating capacity up 500% from 7,600 MW at the end of 1997 to nearly 39,300 MW at the end of 2003. With an average annual increase approaching 32%, wind is the world's fastest growing energy source on a percentage basis, and its growth is forecast to continue a double-digit pace into the next decade 1. While much of this growth is fueled by government decisions that are favorable to 'green' or renewable Power, it is also fueled by advances in wind turbine technology as evidenced by larger, more sophisticated machines. As a result, wind turbines are becoming more established as an economically viable alternative to fossil-fueled power generation. Today, wind 'farms' - consisting of anywhere from a single turbine to as many as several hundred turbines - are an important component of the world's source of electric energy.

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An Analysis of Damping Coefficients for Capillary Type Orifices on a Curved Stabilizer used in a High Speed Rotating Flexible Optical Disk System (고속 회전 유연 디스크 시스템에서 곡면 안정기에 가공된 모세관형 오리피스의 감쇠계수 해석)

  • Song, Ki-Wook;Rhim, Yoon-Chul
    • Transactions of the Society of Information Storage Systems
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    • v.7 no.1
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    • pp.25-30
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    • 2011
  • In the last couple of years, the flexible optical disk(FOD) system that consists of a thin polycarbonate(PC) film of 95 ${\mu}m$ thick, a rigid stabilizer, and a high speed spindle motor has been spot-lighted as the next-generation optical system for archival use of digital data. The air film between the rotating disk and stabilizer provides a means for damping out the lateral disk vibrations. However, its damping-capability drops significantly as the rotational speed of the disk exceeds a specific limit and, eventually, the disk vibration propagates inward causing the whole span of the disk exhibits large vibration amplitudes. Based on the numerical simulations as well as the experimental results, the present work aims to evaluate the damping coefficient of the air-film near the outer region of the disk where the capillary type orifices are applied to the edge of the curved stabilizer.

Web Service Method using WSDL Repository (웹서비스를 위한 WSDL 리포지토리 설계)

  • Choi, Yue-Soon;Park, Jong-Goo
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.11 no.4
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    • pp.745-753
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    • 2007
  • Web service, the next generation of distributed computing, is a distributed solution that handles all businesses through standard techniques in the internet. Web service performs its function using web interface. The goal of this thesis is to reduce network overloading. to manage WSDL efficiently, and to provide convenience to service users by simplifying the web service procedure. Web service system proposed in this thesis is based on WSDL Repository that can include UDDI and store WSDL. WSDL Repository manages WSDL by file system and has UDDI Registry embedded within it. Because this system is based on WSDL Repository, Web service supplier must register WSDL when he registers services. Then, users can receive WSDL too when he searches for services.

Characteristic Analysis of a Linear Induction Motor for 200-km/h Maglev

  • Jeong, Jae-Hoon;Lim, Jae-Won;Park, Do-Young;Choi, Jang-Young;Jang, Seok-Myeong
    • International Journal of Railway
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    • v.8 no.1
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    • pp.15-20
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    • 2015
  • As a result of the current population concentrations in urban centers, demand for intercity transportation is increasing rapidly. Railway transportation is becoming popular as an intercity transportation because of its timely service, travel speeds and transport efficiency. Among the many railway systems, the innovative and environmentally friendly maglev system has been rated very highly as the next-generation intercity railway system. Linear induction motors are widely used for the propulsion of maglev trains because of their light weight and low construction costs. The urban maglev that was recently completed in Incheon airport site employs a 110km/h class linear induction motor. However, this system was designed to meet requirements for inner-city operations and is not suitable as an intercity transportation system, which requires medium to high speeds. Therefore, this study deals with the characteristics and designs of linear induction motors used for the propulsion of maglev trains that can be used as intercity trains. Rail car specifications for high-speed trains have been presented, and the characteristics of linear induction motors that can be used for the propulsion of these trains have been derived using the finite element method (FEM).

Recent Research Trend in Synthesis of Two-Dimensional Graphene through Interface Engineering (계면 제어를 통한 2차원 그래핀 성장의 최근 연구 동향)

  • Lee, Seung Goo;Lee, Eunho
    • Journal of Adhesion and Interface
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    • v.22 no.3
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    • pp.79-84
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    • 2021
  • Graphene has been received a lot of attention as essential parts of future electronic and energy devices. Because of its extraordinary properties contributed from the atomic layer, the interface and surface engineering of graphene are promising approaches for realizing 2D materials-based high-performance devices. Herein, we summarize and introduce recent research trends of the synthesis of graphene through interface engineering for high-performance electronic and energy device applications, and then discuss the challenges and opportunities for achieving high-performance devices in next-generation electronics.

PCR-based markers developed by comparison of complete chloroplast genome sequences discriminate Solanum chacoense from other Solanum species

  • Kim, Soojung;Park, Tae-Ho
    • Journal of Plant Biotechnology
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    • v.46 no.2
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    • pp.79-87
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    • 2019
  • One of wild diploid Solanum species, Solanum chacoense, is one of the excellent resources for potato breeding because it is resistant to several important pathogens, but the species is not sexually compatible with potato (S. tuberosum) causing the limitation of sexual hybridization between S. tuberosum and S. chacoense. Therefore, diverse traits regarding resistance from the species can be introgressed into potato via somatic hybridization. After cell fusion, the identification of fusion products is crucial with molecular markers. In this study, S. chacoense specific markers were developed by comparing the chloroplast genome (cpDNA) sequence of S. chacoense obtained by NGS (next-generation sequencing) technology with those of five other Solanum species. A full length of the cpDNA sequence is 155,532 bp and its structure is similar to other Solanum species. Phylogenetic analysis resulted that S. chacoense is most closely located with S. commersonii. Sequence alignment with cpDNA sequences of six other Solanum species identified two InDels and 37 SNPs specific sequences in S. chacoense. Based on these InDels and SNPs regions, four markers for distingushing S. chacoense from other Solanum species were developed. These results obtained in this research could help breeders select breeding lines and facilitate breeding using S. chacoense in potato breeding.

Efficient Privacy-Preserving Metering Aggregation in Smart Grids Using Homomorphic Encryption (동형 암호를 이용한 스마트그리드에서의 효율적 프라이버시 보존 전력량 집계 방법)

  • Koo, Dongyoung
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.29 no.3
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    • pp.685-692
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    • 2019
  • Smart grid enables efficient power management by allowing real-time awareness of electricity flows through two-way communication. Despite its various advantages, threats to user privacy caused by frequent meter reading hinder prosperous deployment of smart grid. In this paper, we propose a privacy-preserving aggregation method exploiting fully homomorphic encryption (FHE). Specifically, it achieves privacy-preserving fine-grained aggregation of electricity usage for smart grid customers in multiple electrical source environments, while further enhancing efficiency through SIMD-style operations simultaneously. Analysis of our scheme demonstrates the suitability in next-generation smart grid environment where the customers select and use a variety of power sources and systematic metering and control are enabled.

A Review on Fire Safety Engineering: Key Issues for High-Rise Buildings

  • Li, Guo-Qiang;Zhang, Chao;Jiang, Jian
    • International Journal of High-Rise Buildings
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    • v.7 no.4
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    • pp.265-285
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    • 2018
  • This paper presents a state-of-the-art review on the design, research and education aspects of fire safety engineering (FSE) with a particular concern on high-rise buildings. FSE finds its root after Great Fire of Rome in 64 AD, followed by Great London Fire in 1666. The development of modern FSE is continuously driven by industry revolution, insurance community and government regulations. Now FSE has become a unique engineering discipline and is moving towards performance-based design since 1990s. The performance-based fire safety design (PBFSD) involves identification of fire safety goals, design objectives, establishment of performance criteria, and selection of proper solutions for fire safety. The determination of fire scenarios and design fires have now become major contents for PBFSD. To experience a rapid and positive evolution in design and research consistent with other engineering disciplines, it is important for fire safety engineering as a profession to set up a special educational system to deliver the next-generation fire safety engineers. High-rise buildings have their unique fire safety issues such as rapid fire and smoke spread, extended evacuation time, longer fire duration, mixed occupancies, etc., bringing more difficulties in ensuring life safety and protection of property and environment. A list of recommendations is proposed to improve the fire safety of high-rise buildings. In addition, some source information for specific knowledge and information on FSE is provided in Appendix.

Smart Glasses Technologies for Trustworthy, Augmented Reality, See-Through Eyes-Direct Communications as Substitute for Smart Phones (스마트폰 대체재로서의 신뢰증강보는통신용 스마트안경 기술)

  • Song, K.B.;Lee, J.K.;Kim, K.Y.;Kim, G.W.;Park, S.H.;Kim, T.Y.;Yoon, H.S.;Lee, J.H.;Kim, D.H.
    • Electronics and Telecommunications Trends
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    • v.34 no.5
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    • pp.58-70
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    • 2019
  • In this paper, we present the R&D status of ETRI's Trusted Reality (TR) project and its core technologies. ETRI's TR project focuses on the next-generation paradigm of smart phones, ETRI-TR Smart Glasses, which aims to provide the same features as those of smart phones without the involvement of any handheld device. Furthermore, they are characterized by additional features enabled by trustworthy VR/AR/MR/XR, such as privacy masking/unmasking, distributed structure of thin-client computing/networking among TR-Glasses, TR-LocalEdge, and TR-RemoteEdge, with novel see-through eyes-direct communication between IoT real/virtual objects and human eyes. Based on these core technologies of the ETRI's TR project, the human-held ETRI-TR Smart Glasses is expected to aid in the realization of XR vision with particularly more XR's safe_privacy on social life in the near future.

Technical Trends in Next-Generation GaN RF Power Devices and Integrated Circuits (차세대 GaN RF 전력증폭 소자 및 집적회로 기술 동향)

  • Lee, S.H.;Lim, J.W.;Kang, D.M.;Baek, Y.S.
    • Electronics and Telecommunications Trends
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    • v.34 no.5
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    • pp.71-80
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    • 2019
  • Gallium nitride (GaN) can be used in high-voltage, high-power-density/-power, and high-speed devices owing to its characteristics of wide bandgap, high carrier concentration, and high electron mobility/saturation velocity. In this study, we investigate the technology trends for X-/Ku-band GaN RF power devices and MMIC power amplifiers, focusing on gate-length scaling, channel structure, and power density for GaN RF power devices and output power level and output power density for GaN MMIC power amplifiers. Additionally, we review the technology trends in gallium arsenide (GaAs) RF power devices and MMIC power amplifiers and analyze the technology trends in RF power devices and MMIC power amplifiers based on both GaAs and GaN. Furthermore, we discuss the current direction of national research by examining the national and international technology trends with respect to X-/Ku-band power devices and MMIC power amplifiers.