• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.II
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• pp.1386-1389
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• 2005

We report the light illumination effect on the performance of pentacene organic thin-film transistor (OTFT). The TFT performance with and without illumination were measured at various temperatures. The off-state currents increase linearly with light intensity in the region of gate voltage where the holes are majority carriers in the TFT channel. The minimum photocurrents of OTFT increase with increasing light intensity.

• 한국의학물리학회:학술대회논문집
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• 한국의학물리학회 2006년도 제33회 추계학술대회 발표논문집
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• pp.86-86
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• 2006

• Bulletin of the Korean Chemical Society
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• 제24권7호
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• pp.899-900
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• 2003

• 한국컴퓨터정보학회:학술대회논문집
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• 한국컴퓨터정보학회 2014년도 제50차 하계학술대회논문집 22권2호
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• pp.53-54
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• 2014

본 논문에서는 시각 장애인들을 위해 유용한 정보를 제공해 주기 위한 촉각표시장치의 효율적인 정보 표시 방법에 대해 제안한다. 이 방법은 전방에 장애물이 있을 경우 이를 인지 및 촉각 정보로 변환하여 제공함으로 인해 사고를 미연에 예방하고자 한다. 이 방법은 저가의 스테레오 카메라를 이용하여 경제적인 비용으로 구성이 가능하다.

• 한국컴퓨터정보학회논문지
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• 제20권4호
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• pp.11-16
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• 2015

데이터센터는 전 세계적으로 클라우드 기반 IT 솔루션의 발전과 더불어 빅 데이터, 교육, 커뮤니케이션 수단의 발달과 전자기기 사용이 증가함에 따라 국내외로 그 수요가 꾸준히 증가하는 추세에 있다. 이러한 데이터센터의 증가는 IT장비의 발전을 가속화 시켰으며 서버 랙의 발열 또한 크게 높이는 결과를 가지고 왔다. 데이터 센터의 전산 발열량은 IT서버 전력사용의 99%이상이 열로 변환되므로, 서버의 크기와 용량이 증가할수록 발열량 또한 상승하게 된다. 본 논문에서는 공냉식 냉각방식을 중심으로, 데이터센터의 에너지 절감을 위한 공조시스템을 연구 하였으며, 해당 시스템의 성능분석 및 모의실험을 통하여 실제로 에너지 절감 효과가 있는 것으로 분석되었다.

• 융합정보논문지
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• 제9권1호
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• pp.19-27
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• 2019

최근 IT기술의 발전에 따라 2025년 전 세계의 데이터 규모가 현재보다 10배 정도 증가할 것으로 예상한다. 이러한 인터넷 기술의 급속한 발전은 데이터센터 내에서 서버시스템의 고사양화와 저장매체의 대용량화 등을 초래하며, 이는 데이터센터의 전력 소비를 증가시키는 원인이 되고 있다. 이에 본 논문에서는 데이터센터의 서버시스템에 대한 전력 소모패턴을 분석하여 에너지 절전정책을 추천하고 이를 실시간으로 모니터링하는 시스템을 제안한다. 제안한 시스템은 데이터센터의 개별 서버시스템에 대한 전력 소모패턴을 모니터링하고 분석할 수 있으며, 서버시스템의 실제 동작 시간을 효율적으로 관리하여 데이터센터의 전체 전력소모량 대비 10% 내외 정도가 절감될 것으로 기대한다.

• ETRI Journal
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• 제35권3호
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• pp.501-511
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• 2013

Protecting privacy is an important goal in designing location-based services. Service providers want to verify legitimate users and allow permitted users to enjoy their services. Users, however, want to preserve their privacy and prevent tracking. In this paper, a new framework providing users with more privacy and anonymity in both the authentication process and the querying process is proposed. Unlike the designs proposed in previous works, our framework benefits from a combination of three important techniques: k-anonymity, timed fuzzy logic, and a one-way hash function. Modifying and adapting these existing schemes provides us with a simpler, less complex, yet more mature solution. During authentication, the one-way hash function provides users with more privacy by using fingerprints of users' identities. To provide anonymous authentication, the concept of confidence level is adopted with timed fuzzy logic. Regarding location privacy, spatial k-anonymity prevents the users' locations from being tracked. The experiment results and analysis show that our framework can strengthen the protection of anonymity and privacy of users by incurring a minimal implementation cost and can improve functionality.

• JSTS:Journal of Semiconductor Technology and Science
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• 제15권1호
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• pp.114-121
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• 2015

In conventional LEDs, a mesa-structure is usually used and it causes the current to be overcrowded in a specific region. We propose a novel structure of GaN-based LED to overcome this problem. In order to distribute the current in an active region, a spreading pad is inserted at the p-type region in the GaN based LED device. The inserted spreading pad helps the current flow because it is more conductive than the p-type GaN layer. By performing electrical and optical simulations, the effects of the spreading pad insertion are confirmed. The results of electrical simulation show that the current spreads more uniformly and more radiative recombination is produced as well. Moreover, from the optical simulation, it is revealed that the ITO is less absorptive material than p-GaN if the condition of specific wavelength sources is satisfied. Considering all of the results, we can conclude that the luminescent power is enhanced by the spreading pad.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제14권4호
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• pp.1520-1542
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• 2020

Traditional software testing typically uses many physical resources to manually build various test environments, resulting in high resource costs and long test time due to limited resources, especially for small enterprises. Cloud computing can provide sufficient low-cost virtual resources to alleviate these problems through the virtualization of physical resources. However, the provision of various test environments and services for implementing software testing rapidly and conveniently based on cloud computing is challenging. This paper proposes a multilayer cloud testing model based on cloud computing and implements a hybrid cloud testing system based on virtual machines (VMs) and networks. This system realizes the automatic and rapid creation of test environments and the remote use of test tools and test services. We conduct experiments on this system and evaluate its applicability in terms of the VM provision time, VM performance and virtual network performance. The experimental results demonstrate that the performance of the VMs and virtual networks is satisfactory and that this system can improve the test efficiency and reduce test costs through rapid virtual resource provision and convenient test services.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2002년도 Proceedings of International Symposium on Remote Sensing
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• pp.151-156
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• 2002

Recently, as the geographic information system (GIS) which searches, manages geographic information is used more widely, there is more requests for some systems which can search and display more actual and realistic information. As a response to these requests, the video geographic information system which connects video data obtained by using cameras and geographic information as it is by displaying the obtained video data is being more popular. However, because most existing video geographic information systems consider video data as an attribute of geographic information or use simple one-way links from geographic information to video data to connect video data with geographic information, they support only displaying video data through searching geographic information. In this paper, we design and implement a video geographic information system which connects video data with geographic information and supports hi-directional search; searching geographic information through searching video data and searching video data through searching geographic information. To do this, we 1) propose an ER data model to represent connection information related to video data, geographic information, 2) propose a process to extract and to construct connection information from video data and geographic information, 3) show a component based system architecture to organize the video geographic information system.