• Title/Summary/Keyword: dominant period

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Electrical Anisotropy of the Okchon Belt Inferred from Magnetotelluric Data (자기지전류 탐사 자료에 나타나는 옥천대의 전기적 이방성 구조)

  • Lee, Choon-Ki;Lee, Heui-Soon;Kwon, Byung-Doo;Cho, In-Ky;Oh, Seok-Hoon;Song, Yoon-Ho;Lee, Tae-Jong
    • Journal of the Korean earth science society
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    • v.28 no.2
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    • pp.227-239
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    • 2007
  • The MT data at the Okchon Belt show peculiar phase responses exceeding $90^{\circ}$. A reasonable explanation is that those responses are due to an electrical anisotropy structure which is composed of a narrow anisotropic block and an anisotropic layer. Considering the dominant anisotropic strikes of the block (NE-trend) and the layer (NW-trend) inferred from the MT data, if existing, the electrical anisotropy in the Okchon Belt was probably produced by the deformations in the pre-Jurassic period, since the NE-trending shearing or thrusting should create alternating bands of metamorphic rocks and fractures with NE-trending. Correlation of the structural strike of 2-D block with the latest EW-trending deformation events demonstrates that the geometrical structure of the anisotropic block was formed by the latest Daebo and Bulgugsa orogeny.

Mass Mortality of Arkshell, Anadara broughtonii SCHRENCK Seedlings with Marine Ecological Characteristics (해양 생태학적 특성에 따른 피조개 치패의 대량폐사)

  • CHUN Young-Yull;NA Gui-Hwan;CHOI Woo-Jeung
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.24 no.1
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    • pp.70-78
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    • 1991
  • Both long period of summer drought and unusual high water temperature in 1988 caused the harmfull effect to the aquacultural organisms in south coast of Korea. One of those was the mass mortality of arkshell seedlings in Jinhae Bay. The purpose of this study was to verify the effects of environmental factors on arkshell seedlings by investigating not only water quality and food organisms in culturing grounds, but also meteorological conditions. Water temperature in November was higher at $2.0^{\circ}C$ than mean water temperature and the concentration of total inorganic nitrogen and N/P ratio were $0.38{\mu}g-at/l,$ 0.98, respectively which indicated the exhaustion of nutrients, especially nitrogen in the study area. In analysis of phytoplankton population structure, species diversity index(H) , equitability-index(e), species richness $index(d_1)$ were low, but dominance $index({\delta}_2)$ was high at the value of 98.4 and dominant species was Nitzschia pungens. In conclusion, it seems that mass .mortality of arkshell seedlings in November was resulted from the metabolism disorder with poor food organism under the unstable marine environment.

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Physico-chemical Characteristics of Submicron Aerosol at West Inflow Regions in the Korean Peninsula III. Physical-Chemical Behavior and Long-range Transport of PM1 (한반도 서부유입권역에서 대기 중 에어로졸 성분의 물리·화학적 특성 연구 III. 화학적 거동 및 장거리 이동)

  • Park, Taehyun;Ahn, Junyoung;Choi, Jinsoo;Lim, Yongjae;Park, Jinsoo;Kim, Jeongho;Oh, Jun;Lee, Yonghwan;Hong, Youdeog;Hong, Jihyung;Choi, Yongjoo;Lee, Taehyoung
    • Journal of Korean Society for Atmospheric Environment
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    • v.33 no.2
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    • pp.124-138
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    • 2017
  • Physico-chemical measurement of non-refractory submicron particles($NR-PM_1$) was conducted in Baengnyeong Island, Korea using Aerodyne High Resolution Time of Flight Aerosol Mass Spectrometer (HR-ToF-AMS) from 2012 to 2014. Organics and ammoniated sulfate were dominant species in $NR-PM_1$. The organics was found to have similar fractions(approximate 40%) of $NR-PM_1$ during the summer and winter, while the sulfate fractions of $NR-PM_1$ were calculated to be approximately 47% and 31% for the summer and winter, respectively, suggesting the possibility that particles provide non-acidic surfaces for condensation of nitric acid in the winter. The nitrate fractions of approximate 4% and 20% of $NR-PM_1$ were observed in August (summer) and November (winter), respectively, resulting that the relatively low concentration of sulfate in $NR-PM_1$ provided a non-acidic surface for nitric acid condensation and formation of particulate ammoniated nitrate is favored thermodynamically in winter. The new particle formation (NPF) event and particle growth rate were analyzed for each month in 2014 using Scanning Mobility Particle Sizer(SMPS). The Percent of NPF events was the highest in winter, but NPF event was not observed during summer due to relatively high temperature and frequent rainfall. The average particle growth rate was 3.5 nm/h and the highest particle growth rate was 5.5 nm/h in May. We observed the long-range transport of the anthropogenic sulfate from the East Asia during the intensive monitoring period of November between Qingdao and Baengnyeong Island in 2013. The relatively high concentrations of m/z 60 measured in HR-ToF-AMS was observed in May and June at Baengnyeong Island, suggesting the possibility of the influence of biomass burning from the East Asia to the Korean Peninsula.

The Components of the Sap from Gorosoe(Acer mono Max.) and Sugar Maple(Pseudo-sieboldianum Kom.) (고로쇠나무 및 당단풍나무 수액의 성분조성)

  • 성낙주;정미자;김윤숙;이일숙;조종수
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.24 no.6
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    • pp.911-916
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    • 1995
  • Even though the saps have been consumed as beverage in Korea for a very long period of time, a little research has been conducted on the chemical composition. We determined mineral, free sugar, composition amino acids and nucleotides in the sap of Gorosoe(Acer mono Max.) and Sugar Maple(Pseudo-sieboldianum Kom.) collected from Sancheong, Kurye and Hamyang. The contents of solid, crude protein and ash were 1.1~3.3%, 0.03~0.12% and 0.02~0.05% in the sap of Gorosoe and Sugar Maple, respectively. The detectable nucleotides were CMP, UMP, IMP, GMP, AMP and hypoxanthine. Free sugar that we determined in the sap of Gorosoe and Sugar Maple were sucrose, fructose and glucose, but maltose was not detected. The chief component of saccharides in the sap was sugar and ranged from 7.1 to 36.6g/L. Especially, the sucrose contents in the sap of Gorosoe and Sugar Maple from Hamyang were higher 3.7 and 2.2 times than those from the other samples. The prominent minerals in the sap were calcium and potassium. The calcium concentration was ranged from 99.0~153.3mg/L in the sap of Gorosoe and was ranged from 21.2~32.4mg/L in that of sugar maple. The sap of Gorosoe and Sugar Maple were composed of 18 and 15 kinds of amino acid respectively, and the total contents of amino acid were in the range of 0.7~29.3mg%. The major amino acids in the sap of Gorosoe were taurine, serine, glutamic acid and aspartic acid in decreasing order. Taurine contents in the sap of Gorosoe and Sugar Maple was found to be the dominant amino acid.

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Korean Society of 1980s and Minjoong Misool - Visual images of Mass Consumer Society and Re-thinking of the Critical Realism (1980년대 한국사회와 민중미술 - 대중소비사회의 시각이미지와 비판적 리얼리즘의 재고)

  • Choi, Tae-Man
    • The Journal of Art Theory & Practice
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    • no.7
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    • pp.7-36
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    • 2009
  • This paper intends to examine the significance of the "Minjoong Misool(People's art)" of the 1980s emerged in Korea in its social, cultural, and art historical context. This paper also aims to provide an analysis of the meaning and form of the individual artist's works, which have been overlooked under the dominant discourse that has emphasized their political role as a collective group. In particular, this paper scrutinizes the work of "Critical Realists" by examining the way in which they perceived Korean society in the early 1980s and visualized their experiences of the period. The figurative art newly emerged in the early 1980s challenged the formalist Modernism, which was adopted into Korea and translated into monochrome paintings and the work of the conversative academicism of the 1970s. The figurative art encouraged a social communication and moreover it intended to criticize the conflicts in the political, economical, and social domains in Korea. The targets of its critique include the unavoidable results of the unprecedented development of economy, various social phenomena of the post-industrial society, and the growth of the commercialized kitsch culture. Along with Shin, Hak-chul's work that incorporates collage technique since the 1980s, the work of some members of "Reality and Utterance" and "Im- sul-nyun" exemplify their critical interests in disclosing the false dream of wealth and happiness by both referring to and drawing on the utopian fantasy manipulated and distributed by mass media and commercial advertisements. This paper pays particular attention to Nouvelle Figuration emerged in France and Europe during the 1960s, which is comparable to the new figurative art emerged in Korea during the 1980s. Nouvelle Figuration criticized the autonomy in art isolated itself from political and social reality after WWII, in particular the indifference of Informel and abstract art as well as American abstract art. Moreover it became rather politicized around May of 1968. Given that French Nouvelle Figuration was introduced in Korea in 1982 and made a significant contribution to the formation of figurative art in Korea, it should be noted that the new figurative art emerged in the 1980s in Korea cannot be categorized merely in relation to People's Art. This paper intends to critically redress the notion that People's art was formed in the particular political, economical, and cultural context of Korea independent of the contemporary artistic practices outside Korea. It will provide a critical examination and analysis of the content and form of the new figurative art, from which People's Art was germinated, in the global context.

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Analysis of Numerical Experiment for Field Application of Cylindrical Slit Type Block Breakwater (실린더 슬릿형 소파블록 방파제의 실해역 적용을 위한 수치실험분석)

  • Park, Sang-Gil;Lee, Joong-Woo;Nam, Ki-Dae;Kim, Pill-Sung
    • Journal of Navigation and Port Research
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    • v.33 no.10
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    • pp.703-707
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    • 2009
  • In order to evaluate applicability of cylindrical slit type block breakwater to the field water, which was designed from the previous physical model study, it is analyzed the calmness of harbor area by the numerical model experiment. For a small fishery port in southern coast of Korea a SWAN model using the wave action balance equation was formulated. The reflection and transmission coefficients induced by the physical model test were introduced to the numerical model. The model response with cylindrical slit type breakwater was compared with the impermeable breakwater case and the possibility of water quality improvement through the water circulation by the new structure was investigated. For numerical simulation, parameters of deepwater design wave from the prediction report II for overall deepwater design wave by KORDI were used and wind parameters from the 50years return period observed for 37years(1970~2006) were adopted in the numerical model. The response of west breakwater in Mijo port applying the NE and NNE waves, which were dominant in this area, was analyzed. It was found that the transmission characteristic of designed cylindrical slit breakwater was well presented in the numerical model.

Molecular Analysis of the Microorganisms in a Thermophilic CSTR used for Continuous Biohydrogen Production (연속수소생성에 사용되는 고온 CSTR 내의 미생물의 분자적 분석)

  • Oh, You-Kwan;Park, Sung-Hoon;Ahn, Yeong-Hee
    • KSBB Journal
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    • v.20 no.6
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    • pp.431-437
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    • 2005
  • Molecular methods were employed to investigate microorganisms in a thermophilic continuous stirred tank reactor(CSTR) used for continuous $H_2$ production. The reactor was inoculated with heat-treated anaerobic sludge and fed with a glucose-based medium. Denaturing gradient gel electrophoresis showed dynamic changes of bacterial populations in the reactor during 43 days of operation. Gas composition was constant from approximately 14 days but population shift still occurred. Populations affiliated with Fervidobactrium gondwanens and Thermoanaerobacterium thermosaccharolyticum were dominant on 21 and 41 days, respectively. Keeping pH of the medium at 5.0 could suppress methanogenic activity that was detected during initial operation period. $CH_4$ and mcrA detected in the samples obtained from the reactor or inoculum suggested the heat treatment condition employed in this study is not enough to remove methanogens in the inoculum. PCR using primer sets specific to 4 main orders of methanogens suggested that major $H_2$-consuming methanogens in the CSTR belong to the order Methanobacteriales.

Thermophilic Biohydrogen Production from Glucose with a Long-term Operation of CSTR (CSTR의 장기운전을 통한 포도당으로부터의 고온 수소생산)

  • Ahn, Yeong-Hee;Oh, You-Kwan;Park, Sung-Hoon
    • KSBB Journal
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    • v.20 no.6
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    • pp.425-430
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    • 2005
  • Thermophilic $H_2$ was produced for 1 year using a bench-scale continuous stirred tank reactor(CSTR). The CSTR was inoculated with anaerobically digested sludge after heat treatment and fed with a glucose-based medium. The reactor showed relatively short start-up period(30 days) and high maximal $H_2$ yield(2.4 mol $H_2/mol$ glucose). Keeping pH 5.0 or less suppressed methanogenic activity. Bacteria affiliated with Thermoanaerobacterium thermosaccharolyticum kept being dominant from approximately 40 days as determined by DGGE. Environmental perturbation(pH or temperature) caused the decrease of biomass concentration in the reactor and the instability of reactor performance, $H_2$ production rate and $H_2$ yield. The unstable performance was accompanied with high concentration of lactate in the effluent. Taken together, the poor recovery of CSTR after perturbations could be partly explained by low biomass concentration and/or metabolic shift of the major population in the CSTR.

Pollen analysis from Osong Archaeological Site, Chungbuk Province: Vegetation and Environmental Implication (충북 청주시 오송지구 유적 발굴지의 화분분석: 색생과 퇴적환경 고찰)

  • Yi, Sang-Heon;Kim, Ju-Yong
    • The Korean Journal of Quaternary Research
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    • v.24 no.1
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    • pp.25-33
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    • 2010
  • Holocene vegetation and climate changes were assumed on the basis of pollen records from Wonpyeong Trench II-3 of the Osong archaeological site, Cheongju, Chungbuk Province, Korea. An organic matter beared in coarse sediments appeared to be low throughout the succession. Although an occurrence of pollen grains is not high, some dominant and principal taxa may indicate vegetation changes response to climate changes in central inland area of the Korean Peninsula. The age determination can be estimated with indirect way by comparing with previous age-controlled pollen studies. It is assumed that the former last glacial conifer forests had been changed into open mixed conifers and deciduous broadleaved forest during the early Holocene period. Warmer and more humid climate conditions, during the mid-Holocene, might have allowed the hardwoods including deciduous- and evergreen-broadleaved trees, and warm-preferring pine tree to flourish. Subsequently, the former forests were replaced by mixed of conifer and deciduous broadleaved forest owing to deterioration of climate conditions during the late Holocene. Human activity is also detected by agricultural indicators, such as buckwheat and large pollen grains comparable to corn, in upper most pollen profile. During this time, the forests in studied area were primarily affected by human disturbance rather than natural environment.

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The Effects of Warm and Cold Stimulations on the Temperature Distribution in the Prostate (냉.온열의 반복 자극이 전립선 내부의 온도 분포에 미치는 영향)

  • 문우석;백병준;박복춘;김철생
    • Journal of Biomedical Engineering Research
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    • v.23 no.6
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    • pp.467-475
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    • 2002
  • Hyperthermia using transrectal thermal probes has been used for a noninvasive treatment of prostate diseases. However it is known that heating the rectal wall at excessively high temperature can lead to destruction of the rectal mucous membrane. and it is difficult to maintain an optimum temperature over the entire prostate. Thus, a more accurate understanding of the heat transfer mechanism between prostate and hyperthermia system is needed Numerical analysis was performed to investigate how the cold/warm stimulations on the prostate surface affect the temperature distribution in the prostate model. The general purpose software "FLUENT" was used for obtaining a finite volume solution to the unsteady conduction equation and to calculate the time-varying temperature in the prostate. Effects of the warm/cold stimulations and the stimulation frequency on the temperature distribution were simulated. and we visualized how hyperthermia affected the inside of the prostate. It was found that the effect of hyperthermia by using a typical heating method is limited due to the low thermal conductivity of the prostate. Consecutive repetitions of warm and cold stimulations were considered to provide the thermal irritations inside a prostate. The effects of temperature difference and duration of warm/cold stimulations were investigated, and basic data for the optimum period and effective patterns of stimulations were obtained. A simplified bioheat equation was also solved to describe effects of the blood flow on the blood-tissue heat transfer. The effect of blood flow was not dominant compared to that of warm/cold stimulations. These results might be used as data for design of prostate treating probe, prostatic therapy and thermal stimulation effects on the prostate.