• 제목/요약/키워드: hot topic

검색결과 205건 처리시간 0.035초

향후 DC 전력 계통에서의 자려 공진 DC 차단기에 관한 연구 (Study of Self-excited Resonant DC Circuit Breaker in Future DC Grid)

  • 곽정래;윤민한;장길수
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2015년도 제46회 하계학술대회
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    • pp.396-397
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    • 2015
  • With the increasing utilization of high-voltage, direct current (HVDC) transmissions in modern power systems, the DC grid is becoming a hot topic in academic and practical systems. In the DC grid, one of the urgent problems is the fast clearance of the DC fault in the DC network. One preferred method is to isolate the faulty point from the DC network in a short time. The DC circuit breaker is to interrupt the overcurrent after DC faults occur. In this paper, a self-excited resonant DC circuit breaker is an easy and cheap equipment to interrupt the DC fault current. The Mayr's arc model is utilized to simulate the self-excited DC circuit breaker in a DC test system in PSCAD/EMTDC.

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RESOURCE ORIENTED ARCHITECTURE FOR MUTIMEDIA SENSOR NETWORKS IWAIT2009

  • Iwatani, Hiroshi;Nakatsuka, Masayuki;Takayanagi, Yutaro;Katto, Jiro
    • 한국방송∙미디어공학회:학술대회논문집
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    • 한국방송공학회 2009년도 IWAIT
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    • pp.456-459
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    • 2009
  • Sensor network has been a hot research topic for the past decade and has moved its phase into using multimedia sensors such as cameras and microphones [1]. Combining many types of sensor data will lead to more accurate and precise information of the environment. However, the use of sensor network data is still limited to closed circumstances. Thus, in this paper, we propose a web-service based framework to deploy multimedia sensor networks. In order to unify different types of sensor data and also to support heterogeneous client applications, we used ROA (Resource Oriented Architecture [2]).

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A Study on Development of E-Learning Training Course of Shop-master Certificate

  • Son, Mi-Young
    • International Journal of Costume and Fashion
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    • 제9권2호
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    • pp.1-18
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    • 2009
  • Since the 1990s, the domestic fashion industry has been changing rapidly and has become more competitive. Due to these circumstances, the roles of Shop masters were intensified and a training course to acquire a certificate of qualification as a Shop master was in great demand. The 1st Shop master certification exam took place in the year 2001. The purpose of this study was to research the formality of Shop master certificate training courses via e-learning, which is a hot topic in 21st century education, and to provide a development example. First, an analysis was made of the definition and basic characteristics needed of a Shop-master. Next, we noted the problems of former Shop master training facilities and their training process. Thirdly, we did a research on the definition of e-learning and the elements to embody the system. Based on the information obtained through this research, we provided a development example on Shop-master certificate training courses via e-learning that overcame the problems of courses that are currently provided.

수동적 적외선 열화상 기법을 적용한 120W급 LED조명등 건전성 평가 (Soundness Evaluation of 120W LED Lighting using Passive Infrared Thermal Imaging Method)

  • 정윤수;고가진;김재열
    • 한국기계가공학회지
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    • 제16권4호
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    • pp.140-146
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    • 2017
  • As energy conservation and environmental issues are emerging as a hot topic around the world, consumers are demanding high-efficiency, eco-friendly products. In this study, the author proposed 120W LED lighting system that replace metal halide lamp (MHL) which is currently used in the industry. Furthermore, it would be possible to provide a perfect opportunity for Korea to rise as a global leader in the LED lighting industry through soundness evaluation of the LED lighting system that is applied.

Energy-aware Multi-dimensional Resource Allocation Algorithm in Cloud Data Center

  • Nie, Jiawei;Luo, Juan;Yin, Luxiu
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제11권9호
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    • pp.4320-4333
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    • 2017
  • Energy-efficient virtual resource allocation algorithm has become a hot research topic in cloud computing. However, most of the existing allocation schemes cannot ensure each type of resource be fully utilized. To solve the problem, this paper proposes a virtual machine (VM) allocation algorithm on the basis of multi-dimensional resource, considering the diversity of user's requests. First, we analyze the usage of each dimension resource of physical machines (PMs) and build a D-dimensional resource state model. Second, we introduce an energy-resource state metric (PAR) and then propose an energy-aware multi-dimensional resource allocation algorithm called MRBEA to allocate resources according to the resource state and energy consumption of PMs. Third, we validate the effectiveness of the proposed algorithm by real-world datasets. Experimental results show that MRBEA has a better performance in terms of energy consumption, SLA violations and the number of VM migrations.

규조토 및 실리카겔을 혼입한 시멘트 경화체의 열전도율 특성 (Thermal conductivity properties of cement matrix utilizing diatomite and silica gel)

  • 김기훈;편수정;이상수;송하영
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2018년도 춘계 학술논문 발표대회
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    • pp.230-231
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    • 2018
  • Recently, the danger for radioactive materials has become a hot topic. Beginning with the Chernobyl nuclear accident in 1996, in 2011, the Fukushima nuclear power plant in Japan suffered major damage such as large-scale casualties and radioactive dangerous area selection. Concerns about leakage of radioactive materials due to recent earthquakes have been deepening in Korea, such as Wolsong Nuclear Power Plant in Gyeongju, and there is a growing interest in the safety of radioactive materials through the media and the media. However, the route to exposure to radioactive materials is not limited to these large-scale nuclear accidents. Typical examples of this are radioactive substances exposed in daily life. In the case of radon gas, the danger is being revealed through current events programs and news, and natural radiation exposure is attracting attention.

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리튬이온 배터리의 정확한 잔량 측정 기술개발을 위한 연구 방향 제안 (Suggestion of Research Direction for Technology Development on Accurate Measurement of Remaining Capacity in Li-ion Batteries)

  • 주강우;이윤철;하주환;김광선
    • 반도체디스플레이기술학회지
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    • 제15권2호
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    • pp.16-19
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    • 2016
  • More efficient use of the battery pack is dependent upon how to measure the remaining capacity of the battery accurately. Among various measurement methods, the basic correction measurement method has still been a hot research topic area to reduce the errors. In this paper, the problems of the existing methods have been investigated and the research direction for measuring more accurate remaining capacity has been suggested by applying the numerical simulations in the future.

산업용 이차전지의 열화판정에 관한 연구 (A Study on Degradation Diagnosis of Secondary Battery)

  • 남종하;태용준;여인영;최진홍;천창열;김재웅
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2005년도 전력전자학술대회 논문집
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    • pp.170-172
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    • 2005
  • Internal battery ohmic measurements have been a hot topic amongst battery users and battery manufacturers. As a battery deteriorates and loses its capacity, the internal resistance of the battery increases. Everyone seems to agree that measuring the internal parameters of a cell can be very useful in determining a battery's state of health. In this paper experiences show that if a cell's resistance increases by more than25% above its baseline value(known good resistance of new 100% capacity cell), the cell will no loger be able to deliver 80% or more of the rated capacity.

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핫토픽을 이용한 소셜 인플루언서 마케팅 기반의 뷰티 경영정보시스템 (A management information system for beauty business based on social influencer marketing using hot topic)

  • 송재오;조정현;최도진;유재수
    • 한국컴퓨터정보학회:학술대회논문집
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    • 한국컴퓨터정보학회 2018년도 제57차 동계학술대회논문집 26권1호
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    • pp.207-210
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    • 2018
  • 인플루언서(Influencer)란 소셜 미디어에서 유난히 많은 영향력과 파급효과를 가지고 오는 사람들을 말하며, 이들이 만들어내는 콘텐츠는 이제는 자신들의 브랜딩을 넘어선 커머스(Commerce) 효과를 발휘하고 있다. 본 논문에서는 소셜 웹 그리고 공공데이터를 중심으로 뷰티 빅데이터와 방송 콘텐츠 빅데이터를 수집하고 분석하여 상호 상관성에 기반하여 화장품 관련 기업에서 CRM(Customer Relation Management), PLM(Product Lifecycle Management, SCM(Supply Chain Management System) 등의 경영정보시스템과 연계한 뷰티 분야에 최적화된 통합 경영정보시스템을 제안한다.

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Study of the Key Technology of Ghost Imaging Based on Rosette Scanning

  • Zhang, Leihong;Kang, Yi;Pan, Zilan;Liang, Dong;Li, Bei;Zhang, Dawei;Ma, Xiuhua
    • Current Optics and Photonics
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    • 제1권5호
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    • pp.491-499
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    • 2017
  • Ghost imaging offers great potential, with respect to standard imaging, for imaging objects in optically harsh or noisy environments. It can solve the problems that are difficult to solve by conventional imaging techniques. Recently, it has become a hot topic in quantum optics. In this paper, we propose a scheme for ghost imaging based on rosette scanning, named rosette ghost imaging. Sampling a small area sampling instead of the whole object, the instantaneous field of view of rosette scanning is used as the modulation light field in ghost imaging. This scheme reduces energy loss, the number of samples, and the sampling time, while improving the quality of the reconstructed image.