• Title/Summary/Keyword: Snow Fall

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Explication and Rational Conceptualization of Metaverse (메타버스 해석과 합리적 개념화)

  • Song, Stephen W.;Chung, Dong-Hun
    • Informatization Policy
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    • v.28 no.3
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    • pp.3-22
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    • 2021
  • This article reviews previous literature on the metaverse and attempts to provide a refined definition for this phenomenon. Metaverse has recently been in the spotlight among discussions by the industry and the media while a consensus on the exact definition of metaverse is yet to be determined. Since Neal Stephenson first coined the term metaverse in his novel "Snow Crash" in 1992, the Acceleration Studies Foundation (ASF) was the first to analyze the concept of metaverse in 2007. While ASF's effort did not receive much spotlight it may have deserved, metaverse gained much attention in the fall of 2020 when NVIDIA announced its real-time simulation and collaboration platform for 3D production named "Omniverse" as a next-generation alternative for the Internet along with Roblox defining its service as metaverse during its IPO. Since then, metaverse has been commonly recognized as a world where we can cross over reality and virtuality. Based on the two axes and four scenarios proposed by the ASF, we review the literature across four realms as follows - virtual reality, mirror world, augmented reality, and lifelogging. Then, we examine the issues with the existing definition of metaverse and propose an alternative explanation by focusing on human behavior and user experience. Finally, we reassess the concept of metaverse and incorporate human communication, reality-based and virtual-based activities, and eXtended reality as elements to properly define metaverse.

Seasonal and Inter-annual Variations of Lake Surface Area of Orog Lake in Gobi, Mongolia During 2000-2010

  • Yang, Hee-Jae;Lee, Eun-Hye;Do, Na-Young;Ko, Dong-Wook;Kang, Sin-Kyu
    • Korean Journal of Remote Sensing
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    • v.28 no.3
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    • pp.267-276
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    • 2012
  • Terminal lakes are widely distributed in the arid and semi-arid Gobi of Mongolia, and serves as important water resource for local people and livestock. However, such lakes are subject to great fluctuations in its size depending on climatic conditions and human water utilization. The Orog Lake is one such example that has shown remarkable fluctuation in recent years. In this study, we investigated the temporal changes of Orog Lake surface area by using 16-day MODIS 250 m NDVI products from 2000 to 2010. The results were compared with climate variability represented by monthly precipitation and temperature. Our results show that the Orog Lake gradually shrank for the period from 2000 to 2010, but with a significant range of seasonal and inter-annual variability. The lake area showed considerable seasonal variations, as it expanded in spring and fall, primarily due to snow melt and summer precipitation, respectively. Extreme drought period from 2000 to 2002 triggered the substantial reduction in lake area, leading to dry-up in year 2005, 2006, 2007, and 2009. After dry-up once occurred in 2005, the lake repeated reappearance and disappearance depending on seasonal and annual precipitation. Our findings implicate that the ground water fluctuated around the lake bottom level since 2005. This suggests the highly vulnerable nature of Orog lake, which greatly depends on future precipitation change.

A Study on Predictability of Snowfall Amount due to Fine Difference of Spatial Distribution of Remote Sensing based Sea Surface Temperature (원격 탐사 기반 해양 표면 온도의 미세 분포 차이에 따른 강설량 예측성 연구)

  • Lee, Soon-Hwan;Yoo, Jung-Woo
    • Journal of Environmental Science International
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    • v.23 no.8
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    • pp.1481-1493
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    • 2014
  • In order to understand the relation between the distribution of sea surface temperature and heavy snowfall over western coast of the Korean peninsula, several numerical assessments were carried out. Numerical model used in this study is WRF, and sea surface temperature data were FNL(National Center for Environment Prediction-Final operational global analysis), RTG(Real Time Global analysis), and OSTIA(Operational Sea Surface Temperature and Sea Ice Analysis). There were produced on the basis of remote sensing data, such as a variety of satellite and in situ observation. The analysis focused on the heavy snowfall over Honam districts for 2 days from 29 December 2010. In comparison with RTG and OSTIA SST data, sensible and latent heat fluexes estimated by numerical simulation with FNL data were higher than those with RTG and OSTIA SST data, due to higher sea surface temperature of FNL. General distribution of RTG and OSTIA SST showed similar, however, fine spatial differences appear in near western coast of the peninsula. Estimated snow fall amount with OSTIA SST was occurred far from the western coast because of higher SST over sea far from coast than that near coast. On the other hand, snowfall amount near coast is larger than that over distance sea in simulation with RTG SST. The difference of snowfall amount between numerical assessment with RTG and OSTIA is induced from the fine difference of SST spatial distributions over the Yellow sea. So, the prediction accuracy of snowfall amount is strongly associated with the SST distribution not only over near coast but also over far from the western coast of the Korean peninsula.

The Distribution of Precipitation in Donghae-Shi (동해시의 강수 분포 특성)

  • 이장렬
    • The Korean Journal of Quaternary Research
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    • v.13 no.1
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    • pp.45-52
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    • 1999
  • This study examined the spatial distribution of precipitation in Donghae-Shi. The daily, monthly precipitaion on the 2 stations, 3 AWS(Automatic Weather Station) were analyzed by altitudinal distribution, the air pressure type and days of daily precipitation. The results of the study are as follows. 1 Hour greatest precipitation is 62.4mm(1994. 10. 12), Daily greatest precipitation, 200mm(1994. 10. 12), Monthly greatest precipitation, 355.5mm(1994. 10), Maximum depth of snow fall, 35.5cm(1994. 1. 29) in Donghae-Shi, 1993∼1997. Altitudinal distribution of precipitation in Summer tends to have more precipitation at higher altitude, in Winter, high mountains and coast have more precipitation than other sites do. The heavy rainfall in Donghae-Shi is mainly formed by a Typhoon, next is Jangma front. The number of consecutive days of daily precipitation $\geq$20mm is 81days, 44days of those appeared in Summer season. The synoptic environment causes the difference in observed the heavy snowfall amount between high mountains and coast.

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Estimation of the Probability Flood Discharge for Small and Middle Watersheds (중소하천 유역에서의 확률홍수량 분석)

  • Yun, seong-jun;Yu, ui-geun;Kim, byeong-chan;Lee, jong-seok
    • Proceedings of the Korea Contents Association Conference
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    • 2009.05a
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    • pp.442-448
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    • 2009
  • Recently, the natural disaster has occurred as a heavy snow fall, drought and flood by abnormal weather. The damage of human and property by flood is most serious problem among those natural disaster. In order to prepare structural or non-structural measure, to estimate exact flood discharge is important element. This study analyze frequency of hour-unit rainfall data and estimate probability flood discharge by HEC-HMS as changing method of runoff analysis. Also, this study analyze the peak flood discharge sensibility according to Curve Number(CN) with the return period. As a result of estimation of probability flood discharge with the variety CN, to select Antecedent Moisture To select suitable condition(AMC) is important parameter because flood discharge is estimated 40% gap according to AMC.

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Hazard Prevention Using Multi-Level Debris Flow Barriers (다단식(多段式) 유연성 토석류 방지시설에 관한 적용성 검토 연구)

  • Baek, Yong;Choi, Youngchul;Kwon, Oil;Choi, Seungil
    • Journal of the Korean GEO-environmental Society
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    • v.11 no.8
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    • pp.15-23
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    • 2010
  • Debris flows are a natural hazard which looks like a combination of flood, land and rock slide. Large rainfall in July 2006 produced several large scale debris flows and many small debris flows that resulted in loss of life and considerable property and railway damage, as was widely reported in the national media. The hazard "debris flow" is still insufficiently researched. Furthermore debris flows are very hard to predict. Flexible Ring net barriers are multi-functional mitigation devices commonly applied to rock fall or floating wood protection in floods, snow avalanches and also mud flows or granular debris flows, if properly dimensioned for the process or processes for which they are intended. Overtopping of the barriers by debris flows and sediment transport is possible, supporting the design concept that a series of barriers may be used to stop volumes of debris larger than are possible using only one barrier. The future for these barrier concepts looks promising because these barriers represent the state of art for such applications and are superior to many other available options.

The Features of Asian Dust Events Originated in Manchuria (만주에서 발원한 황사현상 (II) -2001년 이후 사례를 중심으로-)

  • Kim, Sumin;Chun, Youngsin;Kim, Seung-Bum
    • Atmosphere
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    • v.20 no.3
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    • pp.273-286
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    • 2010
  • The northeast part of China(hereafter Manchuria) is one of Asian dust source regions along with Gobi, Inner Mongolia and Loess Plateau. In this study, a geographical survey over the area was carried out to determine its soil characteristics in June 2009. It revealed that some parts of the area, especially near Keerchin desert, consist of alkali clay soil mixed up with sand. Manchuria, where is a vast cornfield, can be a potential source region of Asian dust from fall to following spring after harvesting. The frequency of Asian dust over the region from 1996 to 2009 was examined using 3-hourly GTS SYNOP data and it showed that the occurrence of Asian dust over the region is high in the springtime. It was also revealed that snow cover is the key parameter affecting on the frequency through the analysis of NCEP reanalysis data. To scrutinize the path and structure of Asian dust from Manchuria, the event on 3~4 April 2008 and 25 January 2010 were intensively investigated with regard to features of synoptic weather patterns, satellite imagery, airstream, naked eye-observations, concentrations of PM10, 2.5 and 1.0. For this case, the Asian dust from the area reached to Korea less than a day. However, the duration time of the dust in Korea was short (< 7 hours). The average of hourly PM10 reached up to $340{\mu}g/m^{3}$ at Baengnyeondo during the period. The high PM2.5 and PM1.0 concentrations were also observed at several sites in Korea, indicating that air pollutants could be transported along with the dust.

A research for improvement methods in the aspect of safety engineering through risk analysis of facilities for multiple use - Focused on escalator and passenger conveyors - (다중이용시설물 위험분석을 통한 안전공학적 개선 방안에 관한 연구 (에스컬레이터 및 수평보행기를 중심으로))

  • Kwon, Sun-Geol;Kim, Jin-Soo;Kim, Chang-Eun
    • Journal of the Korea Safety Management & Science
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    • v.15 no.1
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    • pp.31-40
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    • 2013
  • For the matter of elevator, one of the multi-use facilities for unspecified public, the JIS has re-established and reformed to apply to the environment in South Korea for the past 20 years. In the aspect of safety assurance, it was inevitable to suggest improved measures. The government, Ministry of Public Administration and Security has secured the safety by enhancing the safety management functions in the elevator inspection standards and expanding its safety device measures. Further, the international inspection standard has been introduced, which is about unifying inspection standard system into the international standard code. In March 14th 2012, the international standard (EN) has been amended and fully announced. Escalator and passenger conveyor among lift devices have several common danger factor that cause safety accident. First, the accident caused by decreased braking power of brake. Second, the accident caused by the rate difference between handrail and tread-board. Third, the accident caused by defects of contraflow preventing device or carelessness inspection. Fourth, the accident caused by wet tread-board or wet floor of platform which makes passenger slip and fall. As the improvements to prevent and reduce these negligent accidents, the inspection list to check and methods should be subdivided and applied for each accident likelihood cause for safety management enhancement and safety assurance of existing escalator and passenger conveyors. The escalators and passenger conveyors without safety devices in existence should be obliged to modify the part of the system or install additional safety device. With making these measures obligations, it requires to improve the system to be suitable for the international inspection standard and to have measures to prevent safety accidents. It also needs to arrange improvements for skid accident of tread-board by the external environment factors such as snow and rain.

Bio-Science and the Problem of 'Two Cultures' (생명과학과 '두 문화' 문제)

  • Kim Hwan-Suk
    • Journal of Science and Technology Studies
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    • v.1 no.2 s.2
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    • pp.311-342
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    • 2001
  • The controversy over the ethics of bio-science in Korea involves not only the conventional 'two cultures' dimension of scientific vs. humane culture, but also another dimension of high vs. popular culture. This paper attempts to analyze the problems of the Korean bio-science controversy and explore a desirable solution with such an extended framework of 'two cultures'. If we investigate this controversy based only on the Snow's 'two cultures' model, we may understand why there have been conflicts between scientists and ethicists. But the possible solution from it may fall into a trap of professionalism, which confines to some suggestions to promote communication and trust between these two expert groups. Therefore, adding the second dimension of high vs. popular culture to this will clearly bring out the problem of separation and conflict between experts and the public. This will also help us to conceive a more fundamental and comprehensive solution. In addition, such an approach can greatly illuminate not only the existing discussion on 'two cultures' but also the cultural role of STS education.

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The investigation of tracking resistant sheath material for ADSS Optic cable (ADSS 광 케이블 시스용 내 트래킹 재료의 특성에 관한 연구)

  • Lee, Jung-Hee;Seo, Il-Gun;Whang, Sun-Ho;Lee, Gun-Joo;Bak, Seung-Yup;Kim, Kyeung-Min;Lee, Seung-Chan
    • Proceedings of the KIEE Conference
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    • 2002.11a
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    • pp.102-105
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    • 2002
  • ADSS(All Dielectirc Self-Supporting) cable installed under high voltage power cable line suffers a variety of environmental influence, rain, wind, snow fall, chemical pollution, salt fog and electrical stress. Its lifetime is required to be at least 20 years with this harsh weathering condition. The electrical stress under high voltage power line gives rise to dry band arcing and tracking, the severest damage, on the outer sheath of cable. Finally tracking might penetrate sheath and cause the break-down of ADSS cable. Tracking resistant sheath material, therefore, should be used to protect the core of ADSS from dry band arcing and to be sure long lifetime. In this work, we discuss various commercial tracking resistant material to investigate the way of track resistance and compare their mechanical, electrical, weathering and tracking properties through serial experiments. We found track resistant material is categorized into two main type : polyethylene with metal hydroxide and polyethylene with reduced carbon black. The Liquid contaminant, Inclined plane Tracking and Erosion test says the time to track of tracking resistant material with metal hydroxide has a little longer time to track in the high applied voltage than that with carbon black, but mechanical and weathering properties were inferior to.

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