• Title/Summary/Keyword: Limestone area

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Desulfurization Characteristics of Domestic Anthracite by Limes at Bench Scale Pressurized Fluidized Bed Combustor . (벤치규모 가압유동층연소로에서 석회석에 의한 국내무연탄의 탈황특성)

  • Han, Geun-Hui;Ryu, Jeong-In;Jin, Gyeong-Tae
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.25 no.10
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    • pp.1373-1383
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    • 2001
  • The desulfurization characteristics of anthracite in a bench scale pressurized fluidized bed combustor are investigated. The coal used in the experiment is domestic anthracite from Kangwon Taeback area. The desulphurization experiment is performed with limestone from Chungbuk Danyang. The pressure of the combustor is maintained at 6 atm, and the combustion temperatures are 850, 900, and 950$\^{C}$. The superficial gas velocities are 0.9, 1.1, and 1.3 m/s. The excess air ratio is varied from 5 to 35%. The Ca/S mole ratios are 0.5, 1.5, 2.5 and 4.5 mole. All experiments are executed at 2m bed height. Consequently, SO$_2$ concentration in the flue gas is increased with incresing bed temperature and superficial gas velocity. However SO$_2$ concentration is decreased with incresing excess air ratio and Ca/S mole ratio.

Comparison of Physical Properties obtained from Geophysical Well Log and Core Property Measurements in Gabsan Formation (갑산층 석회암지역에서의 코어물성과 검층물성 비교)

  • 김영화;김기주
    • The Journal of Engineering Geology
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    • v.9 no.3
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    • pp.253-265
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    • 1999
  • Physical properties of Paleozoic sedimentary rocks in Gabsan formation in Jechon area were obtained by both geophysical well log methods and core property measurements, and the similarity and difference shown between the well log and core log responses were analyzed. The physical properties obtained are natural gamma, resistivity and density. From the difference in density response between the well log and core measurement, the need of correction for natural gamma effect on density log was strongly suggested. And fairly good correlation was obtained between well log and core properties, and among natural gamma, resistivity and density by applying natural gamma correction on density log. It is noted that shale in Gabsan formation reveals very high density, even higher than the density of adjacent non-porous limestone.

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A Microgravity for Mapping Karstic Cavities at Gaeun (가은지역 석회 공동 탐지를 위한 고정밀 중력탐사)

  • Park, Yeong-Sue;Rim, Hyoung-Rae;Lim, Mu-Taek;Koo, Sung-Bon
    • 한국지구물리탐사학회:학술대회논문집
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    • 2008.10a
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    • pp.167-172
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    • 2008
  • A microgravity survey was applied for detecting and mapping karstic cavities over limestone area at Gaeun. The gravity data were collected at about 1, 100 stations by 4 m interval. The density distribution beneath the profiles was drawn by two dimensional inversion based on the minimum support stabilizing functional, which generated better focused images of density discontinuities. We also imaged three dimensional density distribution by growing body inversion. The density image showed that the cavities were dissolved, enlarged and connected into a cavity network system.

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Time-lapse Resistivity Investigations for Imaging Subsurface Grout during Ground Stabilization

  • Farooq, Muhammad;Park, Sam-Gyu;Kim, Jung-Ho;Song, Young-Soo
    • 한국지구물리탐사학회:학술대회논문집
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    • 2007.06a
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    • pp.241-244
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    • 2007
  • Cement-grouts are injected into limestone cavities beneath the road in the project area, in order to improve strength and reduce permeability; the extent to which grout has penetrated in cavities need to be monitored in order to determined effectiveness of cement-grout. Geophysical approaches, offer great potential for monitoring the grout injection process in a fast and cost-effective way as well as showing whether the grout has successfully achieved the target. This paper presents the ability of surface electrical resistivity to investigate the verification of the grout placement. In order to image the cement-grout, time-lapse surface electrical resistivity surveys were conducted to compare electrical resistivity images before and after injection. Cement-grout was imaged as anomalies exhibiting low resistivity than the surrounding rocks. In accordance with field monitoring, laboratory study was also designed to monitor the resistivity changes of cement-grout specimens with time-lapse. Time-lapse laboratory measurements indicated that electrical methods are good tool to identify the grouted zone. Pre-and post grouting electrical images showed significant changes in subsurface resistivity at grouted zone. The study showed that electrical resistivity imaging technology can be a useful tool for detecting and evaluating changes in subsurface resistivity due to the injection of the grout.

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Resistivity Inversion of Underground Cavity Model Using a Multi-Resolution Wavelet (다중분해능 웨이브렛에 의한 지하공동모형의 전기비저항 역산)

  • Suh Baek-Soo;Lee Jae-Young;Kim Yong-In;Lee Chang-Hwan
    • Geophysics and Geophysical Exploration
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    • v.5 no.2
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    • pp.78-83
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    • 2002
  • The finite element method combined with the sensitivity method is adopted for 2-dimensionl Fourier transform inversion. To improve the efficiency of inversion calculation, multi-resolution wavelet method is proposed., Theoretical data which is obtained from above method is shown to examine the proposed method. Theoretical model assumes that underground cavity is located in limestone area. In theoretical model, 16 current and potential electrodes are located to get theoretical data. It is shown that the about inversion method is very exact and useful calculation method, in case the larger model is very small such as under ground cavity.

Geotechnical Considerations in Tripoli Sub-region, Libya (리비아 트리폴리 지역에서의 지반공학적 고찰)

  • 강병무
    • The Journal of Engineering Geology
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    • v.1 no.1
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    • pp.2-10
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    • 1991
  • Some geotechnical considerations might be suggested to the construction performance from the school and the housing projects in Tripoli sub-region, Libya. The subsurface informations were compiled from the site investigation reports, for which more than 700 borings and lots of laboratory test had been conducted from 1984 to 1986. Most subsurface of 10 meter depth in the Jafara plain consists of medium dense silty sand. Some ground in the plain have poor top soil with interbedded calcarenite or limestone. The shallow subsurface is found to be very poor soil in the southern mountain range. Weak soil is hardly found except in the sabkha area. In general, natural silty sand layer may have a presumed bearing capacity of more than 150kN/$m^2$, where spread or strip footing is applied. Proper fine aggregate and natural coarse one are restricted in Tripoli sub-region. Coarse aggregate is generally supplied from the dolomite quarry.

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Taxonomic Review of Clematis flabellata Nakai

  • Beom Kyun Park;Dong Chan Son;Sung Chul Ko
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2020.08a
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    • pp.26-26
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    • 2020
  • Daphne L. (Thymelaceae) comprises about 95 species distributing worldwide from N Africa, N India, SE Asia to E Asia and the coast of the Mediterranean of Europe. In Korea, five species of this genus have been described. In this study, we included four species (D. genkwa, D. pseudomezereum, D. kiusiana, D. jejudoensis) from Korea, excluding cultivated D. odora. The morphological characters through local surveys and the re-classification of the specimens collected in the Korea National Herbarium (KH) were carried out and distribution maps for each taxon were also prepared. The major characters include habit, trichomes in winter bud, leaf, and twig, phyllotaxis, inflorescence, size of calyx lobe and trichomes in the calyx tube, etc. The distribution map showed that D. genkwa is mainly distributed in the coastal area of Hwanghaenam-do, Pyeongannam-do, Jeollabuk-do and Jeollanam-do, whereas D. pseudomezereum is distributed in the limestone zone of Gangwon-do, Jeollabuk-do, and Gyeongsangbuk-do. Similarly, D. kiusiana is mostly found in Jeollanam-do, Gyeongsangnam-do, and Jeju-do. In addition, D. jejudoensis is known to be distributed in forests of Murueng, Andeok, and Seonheul-ri in Jeju-do, but recently, new habitat is discovered in the island forest areas of Jeollanam-do. However, some of these individuals showed the characteristics of D. kiusiana, thus before come to any conclusion detailed taxonomic review of D. jejudoensis and D. kiusiana is required.

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Functions and prospects of oriental health related industries in 21st century (21세기 한방건강관련산업의 역할과 전망)

  • Kim, Kwang-Joong
    • The Journal of Korean Medicine
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    • v.19 no.1
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    • pp.430-443
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    • 1998
  • The research on the actual condition of the oriental health related industry has been made with defining it's phase. As a result, I have come to develope korean-type health model, which can solve the problems derived from the past herb medicine industry. The prospects and roles of the oriental health related industries are as follows: The phase adjustment of the oriental health related industry. The problems of modern medical science happens in the beginning of 21st century, the importance of oriental health improvement in the field of health business is now being on the rise. therefore it is necessary to readjust the present status of the oriental medicine and to take it into health area. Should the responsible institutes regarded on oriental medicine make clear prescription in terms of oriental health industry's role and limitation, they could contribute health circumstance in the 21st century. This is because oriental health related industry can be utiliged in not only protective area and curable area. The present situation of the oriental health related industry. These herb medical societies are flooded with various oriental health industry apart from the legal systematic control so far health industry apart from the legal systematic control so far. The expected survey can not be complete but random under these situations. Nevertheless oriental medical health industry area such as a diet cure, exercise treatment and living condition cure are being considerably expanded, especially living facilities improvement and mind control areas are toward worldwide. Consquently herb health industries are now? consistantly developed by the influence of western nature treatment stemmed from the oriental medicine theory. The role and prospect of the oriental health related industry in 21st century. The oriental health industries can be helpful for the human being's health improvement in general but by the lack of scholastic oriental health theory, it does not contribute to the health welfare. If these problems are made up for in the field of theory area, the oriental health related industry will surely have the potentiallity and know how for health welfare. The successive role of these industry is depended on the fact that the characteristics of the oriental medicine should adjust to the real society with the systematic management. In the 21C, oriental health industry will certainly be vitalized owing to the social and periodical request especially in the area of oriental medical industry, oriental health drink industry, oriental health mind exercise industry, oriental health leasure industry and oriental health complex management industry. Among these areas, it is the oriental health complex amagement industry that will be the limestone of prosperity of the oriental health industry in 21C. Proposal for the social contribution of the oriental health related industry in the 21C. To achive the ultimate role of the oriental health industry in the 21c, first we should know how to use the oriental medicine. Second We should make an effort to revitalize the oriental health industry. So it is indespensible that government, academic institution and enterprise should concentrate their interest on the oriental health industry with common knowledge and systematic management in advance.

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A Study on the Characteristics of the Landslide in Hyuseok-dong(II) -Geological and Hydrological Characteristics- (휴석동(休石洞) 땅밀림형(型) 산사태(山沙汰)의 발생특성(發生特性)에 관한 연구(硏究)(II) -지질(地質) 및 수문특성(水文特性)-)

  • Woo, Bo-Myeong;Park, Jae-Hyeon;Choi, Hyung-Tae;Jeon, Gi-Seong;Kim, Kyung-Hoon
    • Journal of Korean Society of Forest Science
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    • v.85 no.4
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    • pp.571-576
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    • 1996
  • The geological and hydrological survey was carried out in Hyuseok-dong landslide area(10 ha), Youngchoon-myeon, Danyang-gun, Choongcheongbuk-do. The results showed that the bed rocks in this area consisted of shale, sandstone and limestone, and the piles of stones debris were also scattered around the hill above the study area. Soil texture was sandy loam, and bulk density of the soil in the lower part of the area was higher than that of the upper part, but void ratio of the soil in the lower part was lower than that of the upper part. Subsurface water was springing out to the surface in many places in this area. In this area, the storms over 70mm/day were frequent during the summer period from June through September. It was concluded that the occurrence of landslide had a close relationship with the geological characteristics, hydrological conditions and the rainfall distribution.

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Geoacoustic Velocity of Basement and Tertiary Successions of the Okgye and Bukpyeong Coast, East Sea (동해 옥계, 북평 연안 기반암의 지음향 속도와 제3기 퇴적층)

  • Ryang, Woo-Hun;Kwon, Yi-Kyun;Jin, Jae-Hwa;Kim, Hyun-Tae;Lee, Chi-Won
    • Journal of the Korean earth science society
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    • v.28 no.3
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    • pp.367-373
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    • 2007
  • A geoacoustic modeling has been developed to predict sound transmission through the submarine layers of sediment and rock. It demands a geoacoustic model with the measured, extrapolated, and predicted values of geoacoustic parameters controlling acoustic propagation. In the coastal areas of Okgye and Bukpyeong, the East Sea, the marine succession consists of Quaternary/Tertiary deposits and acoustic basement. The basement of Okgye coastal area is indicative of siliciclastics of the Pyeongan Group in Paleozoic, and the average velocities of P-wave and S-wave are 4276 m/s and 2400 m/s, respectively. The basement of Bukpyeong coastal area is indicative of limestone of the Joseon Supergroup in early Paleozoic, and the average velocities of P-wave and S-wave are 5542 m/s and 2742 m/s, respectively.