• Title/Summary/Keyword: Summit

Search Result 269, Processing Time 0.025 seconds

Gas Hydrate Systems at Hydrate Ridge;Results from ODP Leg 204

  • Lee, Young-Joo;Kim, Ji-Hoon;Ryu, Byong-Jae
    • 한국신재생에너지학회:학술대회논문집
    • /
    • 2007.06a
    • /
    • pp.531-533
    • /
    • 2007
  • We report and discuss molecular and isotopic properties of hydrate-bound gases from 55 samples and void gases from 494 samples collected during Ocean Drilling Program (ODP) Leg 204 at Hydrate Ridge offshore Oregon. Gas hydrates appear to crystallize in sediments from two end-member gas sources (deep allochthonous and in situ) as mixtures of different proportions. In an area of high gas flux at the Southern Summit of the ridge (Sites 1248-1250), shallow (0-40 meters below the seafloor (mbsf)) gas hydrates are composed of mainly allochthonous mixed microbial and thermogenic methane and a small portion of thermogenic C2+ gases, which migrated vertically and laterally from as deep as 2-2.5 km depths. In contrast, deep (50-105 mbsf) gas hydrates at the Southern Summit (Sites 1248 and 1250) and on the flanks of the ridge (Sites 1244-1247) crystallize mainly from microbial methane and ethane generated dominantly in situ. A small contribution of allochthonous gas may also be present at sites where geologic and tectonic settings favor vertical gas migration from greater depth (e.g., Site 1244).

  • PDF

Polar-coordinates Linear Interpolation for Map Contour Reconstruction at Summit Area (정상 영역의 등고선 재구성을 위한 극좌표계 선형보간)

  • Hwang Dong-Kuk;Jun Byung-Min;Park Cheon-Joo
    • The Journal of the Korea Contents Association
    • /
    • v.5 no.1
    • /
    • pp.127-134
    • /
    • 2005
  • To connect the gap on the contours at the summit area, we propose the linear interpolation in the polar coordinates. Tn the experiments of applying both existing algorithms and a proposed method to some graphic images, the proposed method generated curves that average MAE was 1.940 pixels. In particular, our method with MAE of 1.240 on real map image was superior than the others. Also by generating new curves with neighbors-resembled appearance, the contours were reconstructed seamlessly.

  • PDF

Design and Implementation of an Image Portal Site for On-Line Album with Content-Based Retrieval (앨범 기능을 포함한 이미지 포탈 사이트의 설계 및 구현)

  • Kim, Gun-Hee;Shin, Dong-Kyoo;Shin, Dong-Il
    • Proceedings of the Korea Information Processing Society Conference
    • /
    • 2000.04a
    • /
    • pp.165-170
    • /
    • 2000
  • 본 논문에서 소개할 온라인 앨범 사이트는 텍스트 기반의 이미지 검색과 색상 기반 검색이 가능한 검색 엔진을 갖추었다. 기존의 검색 엔진들은 매우 단순한 키워드 매칭만을 통하여 이미지를 검색하여 그 결과 이미지와 사용자가 찾고자 하는 이미지 사이의 유사성이 낮은 경우가 많았다. SUMMIT(Sejong University MultiMedia Information Technology)은 등록된 각 사용자에게 개별 공간을 할당하여 사용자가 스스로 원하는 이미지를 업로드하거나 다운로드하게 한다. 또한, 각 사용자는 자신이 구성한 앨범 내에서의 키워드 검색과 내용기반 검색을 수행할 수 있으며 다른 사용자가 공개한 이미지나 시스템 데이터베이스에 저장된 이미지까지 포함한 포괄적인 검색 결과도 획득할 수 있다. 본 시스템은 각 사용자별 페이지 내에서의 검색이 가능하므로 검색의 정확도와 활용도를 높일 수 있다. 사용자는 SUMMIT에 올린 이미지나 타인이 공개한 이미지를 자신 혹은 기타 홈페이지에 직접 하이퍼링크할 수 있으며 어느 페이지에서도 같은 이미지 링크 태그를 사용할 수 있다는 용이함도 취할 수 있다.

  • PDF

Geomorphic Development of Gnamma at the Summit Area of Mt. Geum, Sangju-ri, Namhae-gun, Gyeongsangnam-do (남해군 금산 정상부의 나마(Gnamma) 지형발달)

  • Hwang, Sang-Ill;Park, Hyo-Jung;Park, Kyung-Geun;Yoon, Soon-Ock
    • Journal of the Korean Geographical Society
    • /
    • v.46 no.2
    • /
    • pp.134-151
    • /
    • 2011
  • The types of gnamma at the summit area of Mt. Geum, Sangju-ri, Namhae-gun, Gyeongsangnam-do are classified and geomorphic developments are investigated. The rocks facing the coast show high distributional density of gnamma due to the salt supply from the coast. The water content rate of gnamma distributed in flat rocks at the summit is highest in the bottom area and lowest in the outside area. Moreover, the quartz grains are fallen due to the weathering of feldspar in the crystalline rocks such as granites and the gnamma are merged and expanded as they develop. The average weathering rate of gnamma is 0.04mm/y and it slowed with time. The results on rate indicate that the gnamma are formed and developed at the present rather than the fossil landform or by subsurface weathering.

A Study on the Strength Analysis of the Helmets for Fire and Gas Safety (소방.가스안전용 헬멧의 강도안전성에 관한 연구)

  • Kim, Han-Goo;Shim, Jong-Hyun;Kim, Chung-Kyun
    • Journal of the Korean Institute of Gas
    • /
    • v.12 no.3
    • /
    • pp.31-37
    • /
    • 2008
  • In this paper, the strength analysis has been presented for the stress and strain by using the finite element method for various shell models of the helmets. The advanced helmet that would provide head protection without causing discomfort to the user when it was worn for long periods of time should be manufactured for increasing the safety and workability of the workers. We need a safe, comfortable and light weight of the helmet shell structure. Thus, the helmets had to stand up to the most rigorous conditions encountered for the fire and gas explosion. The FEM computed results show that when the impulsive force is applied on the summit area of a helmet shell structure, the maximum stress and strain have been occurred around the position of an applied impact force, which may lead to the initial failure on the summit of the helmet shell. Thus, the summit area of the helmet shell should be supported by a bead frame and increased thickness of the bead. But the overall thickness of the helmet is to decrease for the light weight of a helmet.

  • PDF

Gas trasport and Gas hydrate distribution characteristics of Southern Hydrate Ridge: Results from ODP Leg 204

  • Lee, Young-Joo;Ryu, Byong-Jae;Kim, Ji-Hoon;Lee, Sang-Il
    • 한국신재생에너지학회:학술대회논문집
    • /
    • 2006.06a
    • /
    • pp.407-409
    • /
    • 2006
  • Geochemical analyses carried out on samples collected from cores on and near the southern smit of Hydrate Ridge have advanced understanding by providing a clear contrast of the two major modes of marine gas hydrate occurrence. High concentrations (15%-40% of pore space) of gas hydrate occurring at shallow depths (0-40 mbsf) on and near the southern summit are fed by gas migrating from depths of as much as 2km within the accretionary prism. This gas carries a characteristic minor component of C2-C5 thermogenic hydrocarbons that enable tracing of migration pathways and may stabilize the occurrence of some structure II gas hydrate. A structure II wet gas hydrate that is stable to greater depths and temperatures than structure I methane hydrate may account for the deeper, faint second bottom simulating reflection (BSR2) that occurs on the seaward side of the ridge. The wet gas is migrating In an ash/turbidite layer that intersects the base of gas hydrate stability on the seaward side of and directly beneath the southern summit of Hydrate Ridge. The high gas saturation (>65%) of the pore space within this layer could create a two-phase (gas + solid) system that would enable free gas to move vertically upward through the gas hydrate stability zone. Away from the summit of the ridge there is no apparent influx of the gas seeping from depth and sediments are characterized by the normal sequence of early diagenetic processes involving anaerobic oxidation of sedimentary organic matter, initially linked to the reduction of sulfate and later continued by means of carbonate reduction leading to the formation of microbial methane.

  • PDF

Rock-Surface Temperatures of the Summit Area of Mt. Halla as a Habitat for an Arctic-alpine Plant Diapensia lapponica var. obovata (돌매화나무 서식지로서 한라산 정상 암벽 표면의 온도특성)

  • Kim, Taeho;Lee, Seung-Wook
    • Journal of The Geomorphological Association of Korea
    • /
    • v.25 no.4
    • /
    • pp.89-101
    • /
    • 2018
  • In Mt. Halla, an arctic-alpine plant Diapensia lapponica var. obovata largely clings to rock surfaces. We observed the rock-surface temperatures of a rocky ridge on the summit area of the mountain from late April 2009 to early May 2010 in order to examine the diurnal and annual temperature variations and the thermal amplitude. We also investigated temperature regimes such as the frequency of freeze-thaw cycles and the temperature change, which might endanger the habitat through frost weathering. For comparison of slope aspects, temperature monitoring was carried out on the north and south faces of the same rocky ridge. The south face experiences the high daily maximum rock-surface temperatures and the high thermal amplitudes during the unfreezing season of May to November 2009. The temperature regimes are considered to exert physiological stress to the arctic-alpine plant. In addition, the south face shows the high frequency of freeze-thaw cycles during the seasonal freezing period of December 2009 to April 2010. This indicates that the south face is susceptible the exfoliation and granular disintegration of rock surfaces, which results in habitat destruction. As a consequence, the south face is believed to be less favorable for the establishment and growth of the arctic-alpine plant than the north face on the summit area of Mt. Halla.