• 한국해양학회지
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• v.28 no.3
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• pp.241-258
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• 1993

To investigate the sedimentary environments on the coastal areas of Imja to Nakweol islands which show very complex shorelines and several zonal sand ridges in NE-SW direction, southwestern coast of Korea, a total of forty samples were taken by a grab sampler and sedimentological and micropaleontological studies on those samples were carried out. The present study area are classified into muddy sandy gravel, sand, city sand, sandy silt and silt facies. With statistical moment parameters such as mean, sorting, skewness and ketosis for the sediments in the study area, the sediments are generally categorized as shallow sedimentary facies. The characters that are observed in quartz grains among the sandy sediments of the study area imply the existence of high energy environments, temporal exposures in atmosphere and the mixing of clastic sediments of the several different origins. In the sediments of the study area, one genera belonging to six silicoflagellata species and five genera belonging to five nannoplankton species were detected. On the basis of the micro-organism assemblage, the study area seems to be influenced by active reworking dominantly under warm water masses. In addition, organic matter ad carbonate contents in the sediments did not show a definite relation with the occurrences of the micro-organisms in the study area.

• Journal of Korean Medical classics
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• v.19 no.2 s.33
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• pp.46-52
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• 2006

${\ulcorner}$황제내경(黃帝內經)${\lrcorner}$ 내함한의학이론(內含韓醫學理論) 기중삼응삼양적내용비상난(其中三陰三陽的內容非常難) 기원인사(其原因是)${\ulcorner}$황제내경(黃帝內經)${\lrcorner}$ 중삼음삼양적내용비상복집(中三陰三陽的內容非常複雜), 특별시삼음삼양적시간배속매편화일양(特別是三陰三陽的時間配屬每篇不日樣) 본론문통과관우(本論文通過關于子) ${\ulcorner}$황제내경(黃帝內經)${\lrcorner}$ 중삼음삼양적시간배속진행연구(中三陰三陽的時間配屬進行硏究), 득출여하결론(得出如下結論), 운기지주기순서춰시오행(목화토금수)순서(運氣之主氣順序就是五行(木火土金水)順序), 저설명주기변화주요근거형지변화(這說明主氣變化主要根據形之變化), 운기지객기순서취시기지대(運氣之客氣順序就是氣之大小)(일양(一陽)${\longrightarrow}$이양(二陽)${\longrightarrow}$삼양(三陽)${\longrightarrow}$일음(一陰)${\longrightarrow}$이음(二陰)${\longrightarrow}$삼음(三陰))${\longrightarrow}$, 저설명객기변화주요근거기지변화(這說明客氣變化主要根據氣之變化) ${\ulcorner}$소문맥해(素問脈解)${\lrcorner}$ 적삼음삼양월별배속시음관(11월:태음)(的三陰三陽月別配屬是陰關(11月:太陰)${\longrightarrow}$양관(1월:태양)(陽關(1月:太陽)${\longrightarrow}$음합(3월:궐음)(陰闔(3月:厥廠)${\longrightarrow}$양합(5월:양명)(陽闔(5월:陽明))${\longrightarrow}$음추(7월:소음)(陰樞(7月:少陰)${\longrightarrow}$양추(9월:소양)(陽樞(9月少陽). 태양소음시음양세력적기초(太陽少陰是陰陽勢力的基礎), 소이상위표리(所以相爲表裏). 소양소음시음양세력적중간(少陽少陰是陰陽勢力的中間), 소이사위표리(所以杞爲表裏) 태음궐음시음양세력적전성기(太陰歐陰是陰陽勢力的全盛期), 소이상위표리(所以相爲表裏) 차료리적의사반영경락류주(此表養的意思反映經絡流注). 태음양명경류주신체전면(太陰陽明經流注身體前面), 태양소음경류주신체후면( 太陽少陰經流注身體後面 ), 소양궐음경류주신체측면(少陽厥陰經流注身體側面). ${\ulcorner}$령추경맥(靈樞經脈)${\lrcorner}$적12경맥류주순서시태음양면경(的12經脈流注順序是太陰陽明經)${\longrightarrow}$소음태양경(少陰太陽經)${\longrightarrow}$궐음소양경적표리경락위주(厥陰少陽經的表裏經絡爲主). 수선매기류주태음양명경적이유(首先脈氣流主太陰陽明經的理由), 취시후천수곡정미화호흡대기결합이형성경맥지기(就是後天水穀精微和呼吸大氣結合而形成經服之氣). 지후맥기류주소음태양경(之後脈氣流注少陰太陽經), 설명순행태음양명경적후천영양물질전입한열경락이위신(說明盾行太陰陽陽明經的後天營養物質轉入寒熱經絡而爲寫薪), 기차맥기순해궐음소양경적(其次脈氣盾行厥陰少陽經的), 인위한열경락지화기피궐음소양경지풍기조절이후조절조습경락(因爲寒熱經絡之火氣被厥陰少陽經之風氣調節而後調節操濕經絡), 비여작반시(比如作飯時), 화기취시소음태양경(火氣就是少陰太陽經), 풍기취시궐음소양경(風氣就是厥陰少陽經), 정내지반취시태음양명경.(鼎內之飯就是太陰陽明經). ${\ulcorner}$령추음양계일월(靈樞陰陽緊日月)${\lrcorner}$ 적삼음삼양월별배속주요시추관합합관추순서(的三陰三陽月別配屬主要是樞關闔闔關樞順序). 저양배서적원인시개문화관문과정(這樣排序的原因是開門和關門過程). 재춘하(在春夏), 양경락지맥기여개문관문과정(陽經絡之脈氣如開門關門過程), 수착추관합합관추순서순행(隨看樞關闔闔關樞順序盾行), 재추동(在秋冬), 음경락지맥기여개문폐문과정(陰經絡之脈氣如開門閉門過程), 수착추관합합관추순행(隨看樞關闔闔關樞盾行).

• Analytical Science and Technology
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• v.27 no.6
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• pp.357-363
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• 2014

Isoprene is a one of the biogenic volatile organic compounds (BVOCs) and it is known as a source of the tropospheric ozone and formaldehyde. In addition, isoprene is a trace component of the exhaled breath and it is a potential biomarker for the diagnosis of diseases such as lung cancer. In these regards, isoprene gas standards are required for the accurate measurement of isoprene in air samples. To establish a standard for isoprene gas, gravimetric preparation and characterization of primary gas standards were studied. The primary gas standards were produced independently in 4 aluminum cylinders and concentrations were examined by GC-FID. As a result, the uncertainty of the gravimetric preparations including purity of the raw material was 0.01% and reproducibility of the preparation of independent 4 cylinders was 0.08%. The primary gas standards for isoprene showed 14 months of long-term stability. The relative expended uncertainty of 2.8% (95% of confidence level, k=1.96) was assigned to the certified value of 10 ${\mu}mol$/mol level of isoprene based on the quantitative evaluation of the purity, weighing, reproducibility, adsorption and long-term stability.

• Korean Journal of Agricultural and Forest Meteorology
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• v.9 no.1
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• pp.61-70
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• 2007

This study was conducted to investigate nutrient dynamics and water quantity of throughfall and stemflow in natural oak stands in Korea. The ratio of the total throughfnll and stemflow to the amount of precipitation varied with locations. It was considered that the ratio was affected not only by the characteristics of tree species but also by regional, weather and other environmental conditions. It was, therefore, necessary to set up a water control system to launch a tending project for natural oak stands. Comparisons of nutrient amount in throughfall among regions reflected regional characteristics. $Ca^{2+},\;Mg^{2+}$ and $K^+$ ions were leached from the canopy and yellow sand accumulation. $Na^+$ and $Cl^-$ were marine-borne. $NO_3^-$ and $SO_4^{2-}$ resulted from dry deposition of air pollutants. Nutrient amount in the stemflow was as low as about 10% of that in the total throughfall and stemflow. The pH of stemflow in natural oak stands in urban areas ranged from 3 to 5. Influx of the acidic stemflow to soil could, in the long term, affect pH in soil solution and nutrient dynamics around root zones.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.7 no.1
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• pp.32-42
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• 2002

The late Quaternary deposit of Cheonsu Bay, up to 20 m in thickness above the Jurassic granite basement, consists of two sedimentary units: an upper Holocene mud and sandy mud deposit (Unit M1), and a lower late Pleistocene sand and mud deposit (Unit M2; 'Kanweoldo Deposit&apos). Unit M1 is a typical Holocene tidal-flat deposit of Cheonsu Bay, showing a coarsening upward, retrogradational facies trend. This retrograding facies trend is probably due to a relative low sedimentation rate during Holocene transgression. Overlain unconformably by Unit M1, Unit M2 deposit reaches up to 14 m in thickness and is mainly composed of muddy sediment with yellow to gray color. This unit is characterized by a variety of tide-influenced signatures such as rhythmic bedding, flaser bedding, crab burrow fossil, marine dinoflagellate assemblage and authigenic glauconite mineral, indicating very similar depositional environment to those of Unit M1 deposit. It suggests that Unit M2 was probably accumulated under the tidal-flat environment during a pre-Holocene sea-level highstand. In particular, the uppermost 3-4 m of Unit M2 appears to have undergone subaerial exposure and subsequent weathering during the sea-level lowstand after deposition. Therefore, stratigraphic unconformity between Holocene and late Pleistocene sediments is highlighted by the desiccated and weathered surface of Unit M2.

• Korean Journal of Agricultural and Forest Meteorology
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• v.9 no.2
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• pp.109-120
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• 2007

The information on flowpath, storage, residence time, and interactions of water and carbon transport in a catchment is the prerequisite to the understanding and predicting of water and carbon cycling in the mountainous landscapes of Korea. In this paper, along with some up-to-date results, we present the principal methods that are currently used in HydroKorea and CarboKorea research to obtain such information. Various catchment hydrological processes have been examined on the basis of the water table fluctuations, the end-member mixing model, the cross correlation analysis, and cosmogenic radioactive isotope activity. In the Gwangneung catchment, the contribution of surface discharge was relatively large, and the changes in the amount, intensity and patterns of precipitation affected both the flowpath and the mean residence time of water. Particularly during the summer monsoon, changes in precipitation patterns and hydrological processes in the catchment influenced the carbon cycle such that the persistent precipitation increased the discharge of dissolved organic carbon (DOC) concentrated in the surface soil layer. The improved understanding of the hydrological processes presented in this report will enable a more realistic assessment of the effects of climate changes on the water resource management and on the carbon cycling in forest catchments.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• v.9 no.1
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• pp.1022-1025
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• 2005

The effect of substrate surface to the formation of ZnO nanostructures has been investigated using Si (111), $Al_2O_3$(C-plane) $Al_2O_3$(A-plane), and $Al_2O_3$(R-plane) substrates. The growth temperature was controlled from 500$^{\circ}C$ ${\sim}$ 600$^{\circ}C$, and the luminescence properties were investigated by a series of photoluminescence (PL) measurements at the elevating temperatures. ZnO nanostructures grown on Si substrate show strong UV emission intensity along with green emission positioned at 3.22 eV and 2.5 eV, respectively. However, green emission was not observed from the ZnO nanostructures grown on $Al_2O_3$ substrates. It is explained in terms of the difference of the surface energy between Si and $Al_2O_3$. Also, the origin of UV emissions has been discussed by using the temperature-dependent PL. The distinction of the PL spectra is interpreted in terms of the difference of the impurity included in the nanostructures.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• v.9 no.1
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• pp.1013-1016
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• 2005

ZnO nanostructure was fabricated by catalyst-free method using Zn powder in air. The growth temperature was controlled from 450$^{\circ}$C to 600$^{\circ}$C, and the structural and optical properties were investigated by scanning electron microscopy (SEM), photoluminescence (PL), energy dispersive X-ray spectroscopy (EDX) and cathodoluminescence (CL). From all samples both ZnO tetrapods and clusters were observed. No significant dispersion was observed from the ZnO tetrapods, however, ZnO clusters show considerable change in density and size. From the EDX results, atomic composition difference was found. The clusters have O-deficiencies, while tetrapods have stoichiometric composition. Strong luminescence was observed at room temperature. From room temperature PL, UV emission at 380 nm and green emission at 500 nm were observed, and the intensity ratio ($I_{uv}/I_{green}$) increased as growth temperature increases. CL measurements show that the UV emission is closely related with tetrapods and the green emission is dominated from the clusters.

• Korean Journal of Ecology and Environment
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• v.49 no.4
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• pp.245-257
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• 2016

Although rivers cover only 0.5% of the total land area on the Earth, they are windows that show the integrated effects of watershed biogeochemistry. Studies on the loads and properties of riverine carbon have been conducted because they are directly linked with drinking water quality, and because regional or global net ecosystem production (NEP) can be overestimated, unless riverine carbon loads are subtracted. Globally, ${\sim}0.8-1.5Pg\;yr^{-1}$ and ${\sim}0.62-2.1Pg\;yr^{-1}$ of carbon are transported from terrestrial ecosystems to the ocean via rivers and from inland waters to the atmosphere, respectively. Concentrations, ${\delta}^{13}C$, and fluorescence spectra of riverine carbon have been investigated in South Korea to understand the spatiotemporal changes in the sources. Precipitation as well as land use/land cover can strongly influence the composition of riverine carbon, thus shifting the ratios among DIC, DOC, and POC, which could affect the concentrations, loads, and the degradability of adsorbed organic and inorganic toxic materials. A variety of analyses including $^{14}C$ and high resolution mass spectroscopy need to be employed to precisely define the sources and to quantify the degradability of riverine carbon. Long-term data on concentrations of major ions including alkalinity and daily discharge have been used to show direct evidence of ecosystem changes in the US. The current database managed by the Korean government could be improved further by integrating the data collected by individual researchers, and by adding the major components ions including DIC, DOC, and POC into the database.

• Journal of Space Technology and Applications
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• v.3 no.1
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• pp.86-99
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• 2023

The mass spectrometer, being an essential scientific instrument for uncovering the origin of the solar system and life, has been used since the early 1970s on board spacecraft to obtain information of neutral and ionized elements in the atmosphere and surface of the moon, planets, asteroids, and comets. According to the 4th Basic Plan for the Promotion of Space Development (2023-2027), Korea plans to conduct lunar landing in 2032 and Mars landing in 2045 as the core goals of the plan and focuses on developing the technologies required for unmanned robotic exploration missions. In this regard, it is crucial to develop the technology of a mass spectrometer, which is the most fundamental payload for space exploration for maximized scientific achievements, however never tried before in any domestic space missions. We describe in this paper the principle of a domestically developed quadrupole mass spectrometer, its prototype model, and the test results of its performance. We conclude this paper with intended future improvements.