• Title/Summary/Keyword: 빙하

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Estimation of Annual Variation of Ice Extent and Flow Velocity of Campbell Glacier in East Antarctica Using COSMO-SkyMed SAR Images (COSMO-SkyMed SAR 영상을 이용한 동남극 Campbell 빙하의 연간 면적변화 및 유속 추정)

  • Han, Hyangsun;Ji, Younghun;Lee, Hoonyol
    • Korean Journal of Remote Sensing
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    • v.29 no.1
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    • pp.45-55
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    • 2013
  • Campbell Glacier in East Antarctica is one of the major glaciers that flow into Terra Nova Bay. It is necessary to estimate accurate extent and flow velocity of Campbell Glacier which influences the dynamics of mass balance of East Antarctic Ice Sheet. However, few studies on Campbell Glacier have been performed since 1990s. In this study, we obtained a total of 59 COSMO-SkyMed SAR images over Campbell Glacier from June 2010 to January 2012. We estimated variations in the extent of Campbell Glacier Tongue and flow velocity of Campbell Glacier by applying the image digitizing and the offset tracking by image matching. Although the extent of Campbell Glacier Tongue decreased in summertime due to ice calving and increased in wintertime, the variation in the extent was very small. Campbell Glacier Tongue retained mean extent of 75.5 $km^2$. The ice discharge of Campbell Glacier Tongue was estimated to be $0.58{\pm}0.12km^3/yr$, which was bigger than in 1989. The flow velocity over Campbell Glacier Tongue was estimated to be from 181 to 268 m/yr that was faster than in 1988-1989, which contributed to the increase in the ice discharge of the glacier.

Absolute Age Determination of One of the Oldest Quaternary(?) Glacial Deposit (Bunthang Sequence) in the Tibetan Plateau Using Radioactive Decay of Cosmogonic $^{10}Be$ and $^{26}Al$, the Central Kavakoram, Pakistan: Implication for Paleoenvironment and Tectonics (방사성 우주기원 동위원소를 이용한 티벳고원에서 가장 오래된 제4기(?) 빙성퇴적물인 Bunthang sequence의 절대 연대측정과 이의 고환경 및 지반운동에 대한 의미)

  • Seong, Yeong-Bae
    • Journal of the Korean Geographical Society
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    • v.42 no.2 s.119
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    • pp.165-176
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    • 2007
  • Absolute age of the deposition of 1.3 km-thick Bunthang sequence within the Skardu intermontane basin of the Central Karakoram was determined using radioactive decay of cosmogonic $^{10}Be$ and $^{26}Al$ burial dating. The Bunthang sequence deposited around 2.65 Ma, which is the oldest glaciation in the region. The timing of deposition of the Bunthang sequence is consistent with the previous suggestion that the basin filling took place between Brunhess and Matuyama chrons. Four major sedimentary facies interfinger within the Bunthang sequence: glacial diamict, lacustrine, fluvial and lacustrine facies upward. This sedimentary distinctiveness and the lack of evidence on the faults for alternative pull-apart basin model around the Bunthang sequence, suggest that the depressional basin was formed by deep subglacial erosion during the exrtensive Bunthang Glacial Stage and subsequently the sediments underlain by basal diamict, was quickly deposited by preglacial and paraglacial processes. Temporary ponding of the Indus River due to tectonic uplift in the downstream or blockage by mass movements might make the basin filing more possible. The hypothesis that the single ice sheet developed on the Tibetan Plateau during the global last glacial cycle should be refuted by the existence of the older extensive Bunthang glacier Furthermore, the extensive glaciation during the early Quaternary (and thus progressive decrease in extent with time) suggests that there may have been significant uplift of the Pamir to the west and Himalaya to the south, which would have reduced the penetration of westerlies and Indian summer monsoon and hence moisture supply to the region.

빙하

  • Hong, Seong-Min
    • The Science & Technology
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    • no.3 s.418
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    • pp.62-66
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    • 2004
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Evaluation of Friction and Hydroplaning Characteristic in Aifield Using Dry Grooving Method (건식그루빙을 사용한 공항 활주로의 마찰 및 수막현상 특성평가)

  • Park, Tae-Soon
    • International Journal of Highway Engineering
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    • v.3 no.3 s.9
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    • pp.111-118
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    • 2001
  • Since the advent of turbojet aircraft with their greater weight and high landing speed breaking performance on runway surface has become un critical. Under certain weather conditions(wet weather, winter) hydroplaning or unacceptable loss of traction can occur, resulting in poor braking performance and possible loss of directional control. To address this concern a number of research project me conducted by NASA, FAA, USAF. The various method which was reported the advantage of the increasing the friction and decreasing the hydroplaning effect. A-2 section of inchon international airport was grooved using drying grooving method. In order to evaluate the effectiveness of the dry grooving method the surface was spray with water and measured the fiction factor and the depth of the water using Mu meter and water depth measuring device. The field test results shooed that the fiction factor nos increased and the depth of the water decreased. The dry grooving method illustrated the reduction of hydroplaning and also, no distress on the runway.

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A Study on the Policy on Digital Contents Archiving in the Field of Science and Technology (과학기술분야 디지털 콘텐츠의 아카이빙 정책 연구)

  • Kwak, Seung-Jin;Choi, Jae-Hwang;Bae, Kyung-Jae;Jung, Young-Mi
    • Journal of Information Management
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    • v.42 no.4
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    • pp.115-136
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    • 2011
  • Recently, the cases of archiving for digital contents are being increased throughout the world. Owing to the characteristics of digital contents including the issues on volatile property and authenticity, preservation weakness, and aging in the reproductive tool, it requires special management for long-term preservation. A successful digital archiving seems to be possible in the stage-oriented practice through the cooperation of interested organizations based on the systematically established and stipulated policy. This is the basic study that was designed for the establishment of the policy on digital contents archiving in KISTI(Korea Institute of Science and Technology Information), which is a representative organization for the distribution of science and technology information. By investigating and analyzing the cases of overseas policies on digital contents archiving, it intended to understand the framework of digital archiving policy while suggesting measures on the macroscopic items that were included in the archiving policies through the interview conducted to expert groups.

A study on Designing Metadata Structure and Element on Web Archiving based on the ISO 14721 OAIS Reference Model (ISO 14721 OAIS 참조모형을 활용한 웹 아카이빙의 메타데이터 구조 및 요소 정의)

  • Oh, Sang-Hoon;Choi, Young-Sun
    • The KIPS Transactions:PartD
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    • v.16D no.5
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    • pp.651-660
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    • 2009
  • This study is to develope the structures and the elements of the metadata for harvesting, management and preservation of a valuable web resources in the web archiving. For this study, we investigated the available metadata in the web archiving and surveyed the requirements of web archiving process. And we analyzed the characteristics of web resources. Also, this study was used a based on the ISO 14721 OAIS Reference Model. Finally, to share the metadata elements among the web archiving system, this study considered the interoperability for the exchange of the metadata. Based on the result, this study designed four structures of the metadata and defined the 28 core metadata elements for the web archiving.

빙축열시스템 최적제어기 개발 및 실증시험

  • 한국전력공사
    • 보일러설비
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    • s.75
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    • pp.88-92
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    • 2000
  • 빙축열시스템의 기존운전방식은 냉동기와 빙축열조의 적절한 조합운전에 의하여 크게 두가지 방식이 이용되고 있다. 이것은 냉동기우선 그리고 빙축열우선 운전방식이며 운전제어의 용이성 그리고 비용측면의 고려 등으로부터 선정되고 있다. 하지만 이러한 운전방식은 운전비용을 절감하기 위한 최선의 기법은 되지 못하고 있으므로, 더욱 운전비를 절감할 수 있는 운전기법을 계획하고 이것으로부터 제어기를 위한 내용에 대하여 설명하고자 한다.

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심야전력 이용 빙축열 시스템

  • 김영인
    • Journal of the KSME
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    • v.32 no.3
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    • pp.255-261
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    • 1992
  • 천연에너지 자원이 부족한 우리 나라에서는 전원 개발의 하나로 원자력 발전소를 건설하여 원 자력 발전이 실제 전체 발전량에서 차지하는 비중의 50.5%를 차지하고 있다. 그러나 원자력 발 전의 경우에는 부하 변동에 따른 발전량의 조절이 불가능하므로 심한 전력부하 불균형을 초래 하고 있다. 이러한 전력부하 불균형 문제를 해결하기 위한 수단으로 야간의 값싼 심야전력을 이용하여 전기에너지를 얼음형태의 열에너지로 저장하였다가 주간에 냉방용으로 사용하는 빙축열 시스템을 채용하면 전력부하불균형 해소와 아울러 값싸게 쾌적한 환경을 얻을 수 있는 장점이 있다. 공조용 빙축열 시스템에서는 열의 생산과 소비의 시간을 임의로 조절할 수 있는 특성이 있다. 이러한 전력사정의 변화 및 생활환경의 변화가 국내에도 파급되어 조만간 국내에서도 공 조용 빙축열 시스템의 설치가 활발할 것으로 예상되어 공조용 빙축열 시스템의 특성, 종류, 구성, 운전방식에 대해 기술한다.

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A Study on Digital Archiving Policy (디지털 아카이빙 정책에 관한 연구)

  • Park, Hyun-Young;Nam, Tae-Woo
    • Proceedings of the Korean Society for Information Management Conference
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    • 2004.08a
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    • pp.69-76
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    • 2004
  • 디지털 아카이빙 정책은 디지털 정보를 보존하여 후대에 이용하도록 하기 위한 필수 요건이다. 디지털 아카이빙 정책은 정보 생성과 보존 활동을 위한 프레임워크뿐만 아니라, 지금 만들어진 안전장치정보에서 즉시 사용을 위한 실제적인 가이드라인을 규정하는 것이다. 본 연구에서는 다양한 유형의 디지털 아카이브즈에 있어서, 그 아카이브즈의 환경과 목표에 따라 규정되어지는 디지털 아카이빙정책의 이론적 배경을 분석하였고, 특히 호주 국립도서관의 디지털 아카이빙 정책과 프랑스 통계자료를 위한 보존 정책을 중심으로 사례 분석하였다.

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