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Output Property of Ge-Thermopile Sensor (Ge계 열전센서의 출력특성)

  • Park, Su-Dong;Kim, Bong-Seo;Oh, Min-Wook
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2006.11a
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    • pp.265-266
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    • 2006
  • It was well known that thermopile was quiet a competent sensor using to probe the temperature of "hot point" where the temperature can be off the temperature-limitation for normal operation of the main electrical power equipment. In the present work, we aimed for developing new Ge-thermopile materials which can be using a non-contact temperature sensors at various hot-point of the power equipment and evaluation of its output property. As a results of the present works, a new thermopile which were composed Ga-poded p-type and Sb-doped n-type in Ge-semiconductor were designed and manufactured by MBE(Molecular Beam Epitaxy) process and showed superior sensitivity at room temperature.

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Counter-Current Flow Limit in Narrow Gap (간극에서의 역방향 유동 제한 현상 연구)

  • Kim, Yong-Hoon;Suh, Kune-Y.
    • Proceedings of the KIEE Conference
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    • 1998.11c
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    • pp.1054-1060
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    • 1998
  • Previous counter-current flow limitation (CCFL) and critical heat flux (CHF) studies included investigations on the inlet entrance, inclined channel and gap effects for the most part. In this study, the local CHF correlation was presented to be used in the numerical analysis for the 3 dimensional hemispherical geometry. Also, first-principle analyses were performed to determine the maximum heat removal capability from the debris through the gap that may be formed during a core melt accident. The maximum heat removal capability by gap cooling can be applied in quantitatively assessing the severe accident management measures.

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Enhanced Multi-Hop Routing Protocol using RSS in Sensor Network (센서 네트워크에서의 RSS(Received Signal Strength)를 이용한 향상된 멀티-홉 라우팅 프로토콜)

  • Lee, Min-Goo;Kang, Jung-Hoon;Yoo, Jun-Jae;Yoon, Myung-Hyun
    • Proceedings of the KIEE Conference
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    • 2005.05a
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    • pp.206-208
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    • 2005
  • Wireless sensor network's value has increased greatly in recent years in the fields of Ubiquitous Computing that function as solution to reduce both the limitation and collision about RFID Technology. The research for wireless sensor network technology is proceeding with the research for various sensor nodes, powerful routing algorithms, securities for data transmission, and valid applications. This paper suggests that we make the new multi-hop routing algorithm using RSS in order to implement enhanced multi-hop routing algorithm. This paper should demonstrate that the routing algorithm using suggested RSS is superior to routing algorithm based on established BSDV(Destination Sequenced Distance Vector).

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A study for PDMS Application Scheme of Digital S/S with IEC61850 Base (IEC61850 기반 디지털 변전시스팀에서의 PDMS 적용 방안에 관한 연구)

  • Lee, D.C.;Kim, H.S.;Bae, U.L.;Min, B.W.
    • Proceedings of the KIEE Conference
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    • 2006.05a
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    • pp.78-82
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    • 2006
  • The Partial Discharge Monitoring System is technology which is available to measure & analysis the partial discharge of Power equipment. This technology is in the limelight as a pre-forecast system of equipment defect but there are some problems like no protocol standard, layered network management and the limitation of physical size. This paper presents whole system structure includes engineering centers, LN(Logical Node) to apply PDMS for, base-digital substation system, ICE61850 compatible Condition Monitoring &Diagnosis (CMD), Local Unit(LU), Intelligent Electronic Device (IED) for the solution scheme of these limitations.

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A Virtual Storage System for Smart Home/Office Embedded Devices (스마트 홈/오피스 임베디드 장치를 위한 가상 저장 시스템)

  • They, Yu-Shu;Kim, Young-Jin;Lim, Hyo-Taek
    • Proceedings of the Korea Information Processing Society Conference
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    • 2007.05a
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    • pp.1237-1239
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    • 2007
  • This paper proposes a virtual storage system for smart home/office embedded devices by utilizing AoE and HyperSCSI protocols. It relies on current Ethernet infrastructures and aims to provide a low-cost solution for the storage limitation problem on embedded devices. We choose AoE (ATA over Ethernet) and HyperSCSI in our implementation because they are relatively lightweight compared to other network storage protocols such as NFS(Network File System), CIFS(Common Internet File System) and iSCSI(internet Small Computer System Interface). The design and architecture of our proposed virtual system as well as the prototype demonstration are presented in this paper.

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A Novel Similarity Measure for Sequence Data

  • Pandi, Mohammad. H.;Kashefi, Omid;Minaei, Behrouz
    • Journal of Information Processing Systems
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    • v.7 no.3
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    • pp.413-424
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    • 2011
  • A variety of different metrics has been introduced to measure the similarity of two given sequences. These widely used metrics are ranging from spell correctors and categorizers to new sequence mining applications. Different metrics consider different aspects of sequences, but the essence of any sequence is extracted from the ordering of its elements. In this paper, we propose a novel sequence similarity measure that is based on all ordered pairs of one sequence and where a Hasse diagram is built in the other sequence. In contrast with existing approaches, the idea behind the proposed sequence similarity metric is to extract all ordering features to capture sequence properties. We designed a clustering problem to evaluate our sequence similarity metric. Experimental results showed the superiority of our proposed sequence similarity metric in maximizing the purity of clustering compared to metrics such as d2, Smith-Waterman, Levenshtein, and Needleman-Wunsch. The limitation of those methods originates from some neglected sequence features, which are considered in our proposed sequence similarity metric.

A Review on Field Constraints for Railway Conflict Detection and Resolution Problem; focusing on the Korean Regional Railway System (열차경합 검지 및 해소 문제를 위한 현실제약의 고찰: 한국철도의 사례를 중심으로)

  • Oh Seog-Moon;Kim Jae-Hee;Hong Soon-Heum;Park Bum-Hwan
    • Proceedings of the KSR Conference
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    • 2004.06a
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    • pp.1374-1378
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    • 2004
  • Railway conflict detection and resolution problem (RCDRP) involves complicated field constraints that should be considered for practical service. In this paper, we address those constraints in brief. Particularly, following situations are addressed; (1) temporal change of network topology, (2) consideration of diverse conditions of track and train, for example, single/double tracks and passenger/freight service, (3) siding capacity limitation, (4) bidirectional sides used by both inbound and outbound trains, (5) regulation for passenger transfer service, (6) consideration of siding length, (7) Restriction on stopping before the track segment with steep slope.

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Damage Identification based on optimization technique for bridges using static displacement (최적화기법에 기초한 정적처짐을 이용한 교량의 손상평가기법)

  • Choi Il Yoon;Lee Jun S;Yim Myoung Jae;Lee Hyun Suk
    • Proceedings of the KSR Conference
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    • 2003.10b
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    • pp.489-494
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    • 2003
  • A damage identification technique using static displacements was investigated to assess the structural integrity of bridge structures. For this, the optimization technique was utilized. In this study, structural damage was represented by the reduction in the stiffness of an element. Next, a health index of the element was introduced to estimate the stiffness reduction of the bridge under consideration. Comparisons with numerical and experimental tests were performed to investigate the applicability of the proposed method in the practical field. Various damage scenarios were considered by varying damage-width as well as damage-degree. The influence of noise on the damage identification scheme was also investigated numerically. Finally, the applicability and the limitation of the proposed method' were discussed.

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Study on The Estimation of Pipeline. Soil Interaction Force. during Longitudinal Permanent Ground Deformation (종방향 영구지반변형 발생시 관$\cdot$지반 상호작용력의 산정에 관한 연구)

  • Kim, Tae-Wook
    • Proceedings of the KSR Conference
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    • 2003.10b
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    • pp.170-175
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    • 2003
  • The ASCE formula of pipeline' soil interaction force is the basis of semi-analytical relationship for buried pipelines subjected to longitudinal permanent ground deformation due to seismic induced liquefaction. However, since the ASCE formula has been developed based on the stiffness of non-liquefied region, it is needed to modify for the varied stiffness of liquefied region. With this object, the consideration of decreasing effect of soil stiffness in liquefied region is made: i.e. the spatial distributions of pipeline. soil interaction force in liquefied region. It means that the improved formula can reflect various patterns of permanent ground deformation more realistically. Through the comparative analyses using both the improved and ASCE formula, the applicability of the improved, the limitation of the existing formula and semi-analytical relationship are discussed.

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The Relationship among Cellular Phone Addiction, Depression, Anxiety, and School Life Satisfaction Perceived by Students (학생들의 휴대폰 중독과 우울, 불안, 학교생활만족도와의 관계)

  • JANG, Sung-Hwa;OH, Eun-Jung
    • Journal of Fisheries and Marine Sciences Education
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    • v.21 no.2
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    • pp.259-268
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    • 2009
  • The purpose of this study was to find out the relationship among cellular phone addiction, depression, anxiety, and school life satisfaction by examining 284 elementary school students, especially the fifth and sixth graders in Gyeonggi province. This study was done by dividing two groups with top 25 percent and the lowest 25 percent of group(addicts' group vs. non-addicts' group), and 144 out of 284 elementary school students were used for this study. According to the survey, it turned out that the significant variables to predict the addiction are school life satisfaction, learning, classroom setting, and school events, including the top variables of anxiety and depression. And a further point is that relationship satisfaction, anxiety, depression, physical setting, and class satisfaction show how much students are addicted to cellular phone. Finally, this paper suggests the limitation and efficiency of the study compared to previous studies.