• Title/Summary/Keyword: Earth Heat

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The Kwinana Shoreline Fumigation Experiment in Western Australia, Australia

  • Yoon, I.H.;Sawford, B.L;Manins, P.C.
    • Proceedings of the Korean Environmental Sciences Society Conference
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    • 1996.04a
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    • pp.22-22
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    • 1996
  • ;The Kwinana Shoreline Fumigation Experiment(KSFE) took place in Fremantle, WA, Australia between 23 January and 8 February, 1995. All measurement systems performed to expectation. The CSIRO DAR(Division of Atmospheric Research) LIDAR measured plume sections from near the Kwinana Power Station(KPS) stacks to up to about 5 km downstream. It also measured boundary layer aerosols and the structure of the boundary layer on some occasions. Both stages A and C of KPS were used as tracers at different times. Radiosonde and double theodolite sounding systems measured temperature, humidity, air pressure and wind structure at the coast(Woodman Point) and at the inland(ALCOA residue dump) site at intervals of roughly two hours. These were supplemented by mid afternoon soundings(radiosonde and single theodolite) by Department of Environmental Protection(DEP) at Swanbourne. The Flinders aircraft measured wind, turbulence and temperature structure of the atmospheric boundary layer, concentrations of $C0_2,\;0_3,\;S0_2\;and\;NO_x$ in the smoke plumes and surface radiation over both land and sea. CSIRO DCET(Division of Coal and Energy Technology) vehicle successfully interceptde many smoke plumes and using a range of tracers will be able to identify the various sources much of the time. Routine data from the DEP and Kwinana Industrial Council(KIC) air quality monitoring networks were also automatically logged. Murdoch University measured surface heat flux at Hope Valldy monitoring station and also at Wattleup monitoring station for the last five days. The heart of the LIDAR system is a Neodymium-doped Yttrium-aluminumgarnet(Nd:Y AG) laser operating at a fundamental wavelength of 1064 nm, with harmonics fo 532 nm and 355 nm. A small fraction of the laser beam is scattered back to the LIDAR, collected by a telescope and detedted by a photomultiplier tube. The intensity of the signal as a function of time is a measure of the particle concentration as a function of distance along the line of the laser shot. The results of nine days special field observations are summarized in detail.etail.

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Synthesis of DyF3 paste and Magnetic Properties of GBDPed Nd-Fe-B Magnets (DyF3 paste 제조 및 이를 이용한 Nd-Fe-B 입계확산 자석의 특성 연구)

  • Jeon, Kwang-Won;Cha, Hee-Ryoung;Lee, Jung-Goo
    • Journal of Powder Materials
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    • v.23 no.6
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    • pp.437-441
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    • 2016
  • Recently, the grain boundary diffusion process (GBDP), involving heavy rare-earth elements such as Dy and Tb, has been widely used to enhance the coercivity of Nd-Fe-B permanent magnets. For example, a Dy compound is coated onto the surface of Nd-Fe-B sintered magnets, and then the magnets are heat treated. Subsequently, Dy diffuses into the grain boundaries of Nd-Fe-B magnets, forming Dy-Fe-B or Nd-Dy-Fe-B. The dip-coating process is also used widely instead of the GBDP. However, it is quite hard to control the thickness uniformity using dip coating. In this study, first, a $DyF_3$ paste is fabricated using $DyF_3$ powder. Subsequently, the fabricated $DyF_3$ paste is homogeneously coated onto the surface of a Nd-Fe-B sintered magnet. The magnet is then subjected to GBDP to enhance its coercivity. The weight ratio of binder and $DyF_3$ powder is controlled, and we find that the coercivity enhances with decreasing binder content. In addition, the maximum coercivity is obtained with the paste containing 70 wt% of $DyF_3$ powder.

A study of seasonal variation of the residual flow before and after Saemangeum reclamation (새만금간척전 .후 잔차류의 계절변화에 관한 연구)

  • 신문섭
    • Proceedings of the Korean Society of Agricultural Engineers Conference
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    • 1999.10c
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    • pp.155-161
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    • 1999
  • The land reclamation area of Saemangeum(Kunsan) is located between 126$^{\circ}$10' E~126$^{\circ}$50' E and 35$^{\circ}$35' N~356$^{\circ}$05'N at the western coast of the Korean peninsula. The are many small islands including extensive areas of semi-diurnally flooded and dewatered tidal flats. The reclamation area of Saemangeum has a range of 5.6m spring tide and the maximum tidal current speed is about 1.41m s-1 in ordinary spring tide. Most of the sediments deposited on the tidal flats are transported from the Geum river, the Manjyung river and The Dongjin river. The soil in this area consists of silty sand with the depth of 10m to 30m . The wind in winter is strong from the direction of northwest. In the past twenty years, land reclamation projects for agricutural purpose or industrial cocmplex have been mostly implemented along the western coast of Korea. Saemangeum coastal area is being constructed the33km sea dike and 40, 100ha reclamation area. The purpose of this study is to find the residual circulations in four seasons after the dike construction by a robust diagnostic and prognostic numerical model. Heat flux at the sea surface in January ,May , August , October was asopted on the basis on the daily inflow of solar radiation at the earth surface, assuming an average atomospheric transmission and no clouds , as a function of latitude and time of year(George L.P.J.E William, 1990). The discharge from the Geum , the Mankyung and the Dongjin rivers was adopted on the basis of experience formula of river flow in January , May ,August, October (The M. of C.Korea, 1993) . Water temperature and salinity along the open boundaries are obtained from the results of field observation s.

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A Study at Investigating the Climate Change in East Asia with Changing Sea Surface Temperature

  • Park, Geun-Yeong;Lim, Yong-Jae
    • Journal of Integrative Natural Science
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    • v.13 no.1
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    • pp.27-33
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    • 2020
  • The unsustainable human activities like increased use of automobiles, heavy industrialization and the use of large volumes of fertilizers, chemicals and pesticides in the agricultural land cause climate change problems in one way or another. Under normal circumstances, the heat radiations from the sun will be reflected back. An excessive volume of GHGs in the atmosphere would prevent these radiations from reflecting back. East Asia is facing severe climate change issues in recent times. A lot of climate change problems such as hurricanes and floods have been reported from this region in the last couple of decades. The study aimed at investigating the climate change in East Asia with changing Sea Surface Temperature (SST). The study adopted a quantitative research method with a case study research design where a deliberate focus was made on the East Asia Region. Secondary data was gathered and analyzed to yield both descriptive and inferential statistics. The study concluded that the impact of East Asia Climate variability was significant mainly for some extreme events. Also, the study concluded that there was a significant link between the change of the East Asia climate variability and that of the sea surface temperature. Further, the study concluded that a linear relationship existed between the sea surface temperature and the climate of East Asia. Hence, a linear regression was a significant predictor of the East Asia Climate (EAC) based on changing sea surface temperature. The model revealed that 37.4% of the variations in the climate change index were explained by the changes in the sea surface temperature. The climate was expected to change with a value of 49.48 for a unit change in the sea surface temperature.

A Study on the Dwellings of Korean Diaspora in Russia and Central Asia (옛 소련 지역 한국인 동포의 주거건축에 관한 연구 - 단독주택 평면을 중심으로 -)

  • Lee, Sang-Hae
    • Journal of architectural history
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    • v.13 no.4 s.40
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    • pp.19-34
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    • 2004
  • This study examines the dwellings of the Korean diaspora in Maritime Provinces of Russia, and Kazakhstan and Uzbekistan of Central Asia to find the gist of the residence transformed as Korean traditional residence culture to accept Russian foreign culture. Through the examination, transformation process of the dwellings of the Korean diaspora was found as follows: - 1st Period(1864-1937): The Korean diaspora who Immigrated to Maritime Provinces of Russia built traditional houses of Korean style and few of them lived in Russian style houses. - 2nd Period(1937-1955): The Koreans who immigrated to Central Asia from Maritime Provinces under compulsion built 'ground house' by digging the earth and installed gudeul which is a traditional Korean heating system and roofed with reed. - 3rd period(1955-1991): The Koreans built straight lined '-' shape houses with two or three rooms wherein most of them were installed with gudeul to heat the room. Around the 1940s as they economically got well, the Koreans started to build houses with Russian style with one or two rooms with gudeul or a separate building with gudeul. - 4th period(1991-present): Houses of the 3rd period are still used by being enlarged or remodeled with less use of gudeul which is well reflected on Ujeong-maul village in Russia Maritime Provinces. As can be found above, the dwellings of the Korean diaspora in Russia Maritime Provinces and Central Asia are on the process of being transformed into Russian style to adapt to Russian culture.

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Crystal Structure and Photoluminescence of Domestic Natural Alkaline Feldspar (국산 천연알카리 장석의 결정구조와 Photoluminescence)

  • Choi, Jin-Ho;Cheon, Chae-Il;Kim, Jeong-Seog
    • Journal of the Korean Ceramic Society
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    • v.44 no.5 s.300
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    • pp.155-159
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    • 2007
  • Blue light-emitting phosphors having the excitation spectrum range of the medium-long ultraviolet ($280nm{\sim}400nm$) have been prepared by solid state reaction method. As a starting material the natural alkaline feldspar powder produced from the domestic mine field in Buyeo, Chungnam-do. The photoluminescence characteristics and crystal structures have been analyzed for the phosphor samples. The powder mixture of the natural alkaline feldspar and the rare-earth oxide was calcined at $800{\sim}1000^{\circ}C\;for\;3{\sim}4h$ in air. The calcined samples we fully ground at room temperature and then heat-treated in the mild reducing gas atmosphere of $5%H_2-95%N_2$ mixture at $1100{\sim}1150^{\circ}C\;for\;3{\sim}4h$. The natural alkaline feldspar material consists of the monoclinic orthoclase ($KAlSi_3O_8$) and the triclinic albite ($NaAlSi_3O_8$) phases. At the $0.5wt%Eu_2O_3$ addition the PL spectrum showed the maximum intensity and with further increase of $Eu_2O_3$ the PL intensity decreased. The albite phase disappeared in the $Eu_2O_3$ doped phosphors. The effect of the co-doped activator on the PL characteristics have been also discussed.

Synthesis and Physical Properties of Sm Doped Pb Free 3 Phase-Glasses (Sm 농도에 따른 무연 3상 유리계의 합성과 물리적 성질)

  • Park, Jong-Ho
    • Korean Journal of Materials Research
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    • v.22 no.7
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    • pp.368-373
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    • 2012
  • Glasses were prepared with compositions of $(13-x)BaO-80B2_O_3-7Li_2O{\cdot}xSm_2O_3$, BBLSx(x=0.5, 0.4, 0.3) by melting the starting materials of boron oxide(99.9%), lithium oxide(99.9%), barium carbon oxide(99.9%), and samarium oxide(99.9%) and then quenching the melt at $1350^{\circ}C$. This led to good-quality BBLSx(x=0.4, 0.3) and poor-quality BBLSx(x=0.5) glasses. The physical and structural properties of the BBLSx glasses were studied by means x-ray diffraction, scanning electron microscopy(SEM), differential scanning calorimetry(DSC), and dielectric spectroscopy. From the x-ray diffraction and SEM results, the quality of the BBLSx glasses significantly depends on the $Sm_2O_3$ concentration. The x-ray diffraction pattern showed that the crystallites in the BBLSx glasses after heat treatment at $700^{\circ}C$ may be $LiBaB_9O_{15}$. From the DSC results, the glass transition temperatures($T_g$), crystallization temperatures($T_c$), and the maximum temperatures of the crystallized($T_p$) BBLSx glasses all changed with the $Sm_2O_3$ concentration. According to the dielectric spectroscopy results, the values of the real dielectric constant and Tan ${\delta}$ of the BBLSx glasses depended on the $Sm_2O_3$ concentration. The values of the real dielectric constant and Tan ${\delta}$ were also shown to depend on the measuring temperature, possibly due to the ion migration in the bulk of the BBLSx glasses.

Development of Thermal-Hydraulic-Mechanical Coupled Numerical Analysis Code for Complex Behavior in Jointed Rock Mass Based on Fracture Mechanics (균열 암반의 복합거동해석을 위한 열-수리-역학적으로 연계된 파괴역학 수치해석코드 개발)

  • Kim, Hyung-Mok;Park, Eui-Seob;Shen, Baotang;Synn, Joong-Ho;Kim, Taek-Kon;Lee, Seong-Cheol;Ko, Tae-Young;Lee, Hee-Suk;Lee, Jin-Moo
    • Tunnel and Underground Space
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    • v.21 no.1
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    • pp.66-81
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    • 2011
  • In this study, it was aimed to develop a thermal-hydraulic-mechanical coupled fracture mechanics code that models a fracture initiation, propagation and failure of underground rock mass due to thermal and hydraulic loadings. The development was based on a 2D FRACOD (Shen & Stephasson, 1993), and newly developed T-M and H-M coupled analysis modules were implemented into it. T-M coupling in FRACOD employed a fictitious heat source and time-marching method, and explicit iteration method was used in H-M coupling. The validity of developed coupled modules was verified by the comparison with the analytical result, and its applicability to the fracture initiation and propagation behavior due to temperature changes and hydraulic fracturing was confirmed by test simulations.

Chest Pain and Hyungsang Medicine (흉통(胸痛)의 형상의학적(形象醫學的) 치료)

  • Oh, Chung-Hwan;Kang, Kyung-Hwa;Lee, Yong-Tae
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.20 no.5
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    • pp.1117-1125
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    • 2006
  • A study is made on the chest pain in the perspective of Hyungsang medicine. The following are the conclusions produced by the examination on the clinical cases of chest pain. Excessive atmospheric influences (wind, rain, cold and summer heat) are the exogenous causes of chest pain. The endogenous causes are diet, dwelling, sexual life and emotions. Persons of bird type are attacked by the chest pain because of emotional depressions. Those of running animal type get sick of chest pain when wood checks earth. Those of turtle type are a afflicted with chest pain due to depression and stagnation of Ki. Those of fish type suffer from chest pain when the ministerial fire of the liver and kidney becomes hyperactive. Chest pain is causes by leakage of Jung for the Jung kwa person, by stagnation of Ki for the Ki kwa person, by flaming fire due to deficiency of Yim for the Shin kwa person and Dy failure of water and fire in complementing each other for the Hyul kwa person. Chest pain often occurs to persons with the following characteristics upward nose, Dig eyes, chapped lips, pronounced foot of nose, red or yellow complexion, frowning face and wrinkles on the nasal radix. Among the six meridian types, chest pain is often found in the persons of Yangmyung and Taeum meridians. Women suffer from chest pain more often than men because breast is a center of life to her.

Development of DC Arc Generator to protect against Malfunctions and Fires caused by Arcing (아크 발생에 따른 고장 및 화재를 보호하기 위한 직류 아크 Generator 개발)

  • Yoon, Yongho
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.21 no.6
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    • pp.123-128
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    • 2021
  • As the spread of DC power distribution systems increases, the occurrence of failures and fire accidents are also increasing. In particular, the ESS fire accident, which is a component of the smart grid, and the fire accident of the solar power system, which is a direct current system, are caused by problems in the electrical connection between system components as the supply of new and renewable energy rapidly increases and old facilities increase. An arc that can cause a direct fire by releasing the induced light and heat has been pointed out as one of the causes of fire. Therefore, the problem of such an arc defect is that it is impossible to block an arc accident in advance with the existing overcurrent circuit breaker and earth leakage circuit breaker. In this paper, we intend to develop a test equipment that satisfies international standardization and to develop a DC arc generator to protect against failure and fire caused by arcing.