• Title/Summary/Keyword: 김주용

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Geochemical Characteristics and Contamination of Surface Sediments in Streams of Gwangju City (광주광역시 하천의 표층퇴적물에 대한 지구화학적 특성과 오염)

  • Kim, Joo-Yong;Koh, Young-Koo;Youn, Seok-Tai;Shin, Sang-Eun;Park, Bae-Young;Moon, Byoung-Chan;Kim, Hai-Gyoung;Oh, Kang-Ho
    • Journal of the Korean earth science society
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    • v.24 no.4
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    • pp.346-360
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    • 2003
  • In order to investigate the geochemical characteristics of surface sediments in streams of Gwangju City, sediment samples from the main stream of Yeongsan river, Hwangryong river, and Gwangjucheon in the city were collected and analyzed for grain size and metal and organic carbon contents. The sediment types of the streams widely vary from pebble to mud. The metal contents in the sediments from Yeongsan river and Hwangryong river are mainly dependent on the grain size of the sediments and the geology around the streams, while the sediments in Gwangiucheon are controlled by organic matter contents from the domestic sewage. The enrichment factor (Ef) and index of geoaccumulation (Igeo) representing the degree of metal contamination in the sediments are relatively low in the mainstream of Yeongsan river and Hwangryong river. However, those of Gwangjucheon show EF values of P=8.30, Cu=5.54, Zn=14.28 and Pb=7.41 and Igeo values of P=3.78, Cu=2.79, Zn=3.66 and Pb=1.59. The heavy metal contamination is especially significant near the area where the Seobangcheon and Donggyecheon branches of Gwanjucheon, join. Therefore, it is suggested that the metallic contaminations of these small streams are significantly influenced by the domestic sewage of the city.

Shape Design of Bends in District Heating Pipe System by Taguchi Method (다구찌 방법을 이용한 지역난방시스템의 벤드형상 설계)

  • Choi, Moon-Deok;Kim, Joo-Yong;Ko, Hyun-Il;Cho, Chong-Du
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.34 no.3
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    • pp.307-313
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    • 2010
  • In this study, alternative designs for the bends used in district heating pipes are investigated. The district heating pipes, which are subjected to temperatures of 10 to $120^{\circ}C$ and a water pressure of $16\;kgf/cm^2$, have to withstand thermomechanical cyclic loads when in use. These pipes comprise three concentric tubes: a steel pipe (internal), polyurethane (PUR) insulator (middle), and a high-density polyethylene (HDPE) case (external). In addition, the bends in the district heating pipe system are covered with foam pads that cause aging. In this study, an alternative bend design that does not involve the use of a foam pad is proposed to overcome the aging problem in the bends. In the proposed design, "shear rings" are added to the surface of a bend, and its dimensions are determined by a combination of the statistical (Taguchi) method and FEM. The geometrical parameters such as thickness, height, and number of the rings significantly affect the design optimization, and hence, they affect the results of the FEM.

The Locational Characteristics of Cultural Sites Found in South Korea (남한에 분포하는 유적의 분포 특성)

  • Lee, Jin-Young;Hong, Sei-Sun;Yang, Dong-Yoon;Kim, Ju-Yong
    • Journal of the Korean Association of Geographic Information Studies
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    • v.14 no.2
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    • pp.14-27
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    • 2011
  • Cultural remains distribution maps have been published in 172 volumes of books, and the information about the remains in South Korea is also disclosed via the Internet to those who are interested in conducting archeological examinations or to those who are planning the national land use for various purposes. The purpose of this study is to statistically review the locational characteristics of the sites appearing in cultural sites map, and to determine the locational characteristics of these remains or sites. The location of sites was statistically analyzed based on the point density function of geographic information system of 87,859 sites found in cultural site maps. The results of this study show that the sites found in South Korea are mainly distributed around historical cities and the distributions are closely related to their proximity to rivers. Given that the period of time and type is very important to archeological studies, the results of this study indicate that detailed period of time and type may be necessary for further analysis. This study has highlighted that the research into the spatial analysis and interpretation of cultural heritage sites can contribute to the field of archeological studies.

Postglacial Vegetation History of the Central Western Region of the Korean Peninsula (한반도 중서부 지역의 후빙기 식생 변천사)

  • Jang, Byeong-O;Yang, Dong-Yoon;Kim, Ju-Yong;Choi, Kee-Ryong
    • Journal of Ecology and Environment
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    • v.29 no.6
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    • pp.573-580
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    • 2006
  • A sediment core from the Cheollipo arboretum ($36^{\circ}$ 47' 57'N, $126^{\circ}$ 09' 04') was studied for pollen analysis in order to reconstruct postglacial vegetational change and environmental changes around the central western region of the Korean Peninsula. The record shows four pollen assemblage zones: Zone CHL-I, Quercus stage (ca. 9,300$\sim$6,200 yr BP): zone CHL-II, Quercus-Pinus stage (ca. 6,200$\sim$4,600 yr BP); zone CHL- III, Pinus-Quercus stage (ca. 4,600$\sim$1,160 yr BP): zone CHL-IV and Pinus stage (ca. 1,160 yr BP-present). During the 9,300$\sim$8,500 yr BP, the early Holocene, researchers have guessed a piece of cool-temperate norihern/altimontane mixed coniferous and deciduous broad-leaved forest. Between 8,500$\sim$4,600 yr BP the Quercus dominated the landscape of study area and the established dates of this typical cool-temperate central/montane deciduous broad-leaved forest vegetation might be ca. 6500 yr BP, and then the Pinus developed around the site at ca. 5,700 yr BP. The abrupt increase of Pinus and NAP (non-arboreal pollen) after ca. 1,100 yr BP indicates the vegetation changes due to human activities. From the dynamics of the Chenopodiaceae pollen indicating salt marsh and freshwater pollen flora such as Typha, Trapa, Nymphoides and so forth, we suggest that the tidal flat was altered into freshwater lake around 6,500 yr BP.

Environment of Fluvial Sedimentary Deposits and Palynological Occurrence in the Geochang Area (거창 지역 하성퇴적층 형성환경과 화분산상 연구)

  • Kim, Ju-Yong;Yang, Dong-Yoon;Bong, Pil-Yun;Kim, Jin-Kwan;Oh, Keun-Chang;Choi, Don-Won
    • The Korean Journal of Quaternary Research
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    • v.20 no.1 s.26
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    • pp.39-50
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    • 2006
  • Jeonjangri site of Geochang area is located in the Geochang Basin, and lies on the river terrace of upstream part of Hwang River. Fluvial deposits are well distributed at the northern and southern walls of trench 2(district 2) in the Jeonjangri archeological site. This study aims to interpret the occurrences of fluvial sedimentary deposits on the basis of grain size analysis and palynological analysis in the representative sections of Jeongjangri site. The sedimentary profile shows that the upper units are typified by paleosols with soil wedge formed at about $25,000{\sim}30,000yr$ B.P, and the lower units are characterized by reddish brown muddy sands, organic muds and sand/gravel downwards in the profile. Particularly palynological study on the organic muds of southern wall section showed a result that lower unit is dominant with grass vegetation, and upper unit with Alnus-Quercus-Pinus vegetation. The former is interpreted to be formed at $60,000{\sim}50,000yr$ B.P (stadial), while the latter at $80,000{\sim}70,000yr$ B.P. In general broad-leaved/coniferous mixed forests are mostly dominant in Jeongjangri site and the climate was presumed to be cool temperate at that time.

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Manufacturing Techniques and Provenance of Earthen Wares in Daecheonri Prehistory Site of Okcheon County, Korea (옥천 대천리 유적지 토기의 제작기법 및 원료산지 분석)

  • Lee, Hyo-Min;Yang, Dong-Yun;Gu, Ja-Jin;Kim, Ju-Yong;Han, Chang-Gyun;Choe, Seok-Won
    • The Korean Journal of Quaternary Research
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    • v.18 no.1 s.22
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    • pp.1-20
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    • 2004
  • A geoscientific research was performed on 12 samples of comb-pattern potteries which were excavated at Daecheonri neolithic site, Korea. The texture and compositions of 12 potteries and surrounding metrix of soil and rocks were compared with the help of petrographic microscope, XRD and REE data. As to the manufacturing techniques thick potteries are caused by the amount and number of coarse grains which are assumed to be added shards when their distributional pattern are considered. DC1, DC3, DC 7 and DC11 samples have clearly oriented textures, and the orientation of vesicles in DC3 and DC11 samples arranged in the same direction with those on the pottery surface. This indicates the use potter's wheel technique in manufacturing potteries. Burning temperature is assumed over $800^{/circ}C$, particularly under reduction environment. As to the source, raw materials of pottery matrix are derived from the bottom of excavation site, or in an extracted outcrop of the northwestern foothill from site, while the shard materials are very similar with those extracted from sandy loams near sites. Finally any use pattern of pottery may control the pottery thickness, shard addition, and matrix selection.

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지질시대 및 지구조별 국내대리석 석재자원의 분류와 물성

  • 윤현수;홍세선;박덕원;이병대;김주용
    • Proceedings of the KSEEG Conference
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    • 2002.10a
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    • pp.153-169
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    • 2002
  • 국내 대리석류 석재자원은 지질시대 및 지구조별로 선캠브리아기의 경기육괴와 영남육괴, 시대미상의 옥천대 남서부, 캠브리아-오오도비스기의 옥천대 북동부, 그리고 일부 기타시대의 옥천대 북동부 등으로 분류될 수 있다. 전자는 변성퇴적암류내에 협재된 결정질 석회암, 화강암질 편마암내 포획된 결정질 석회암 등s으로 경기육괴의 포천, 김포, 온수리, 목계와 신림도폭 그리고 영남육괴의 춘양, 현동, 울진, 중평동, 장기리와 장계도폭 등이 해당된다. 시대미상암류는 옥천대 남서부로서 목계, 충주, 괴산, 강경, 남원과 송정도폭, 그리고 캠브리아기는 풍촌석회암으로 임계, 호명, 서벽리도폭 등기 해당된다. 오오도비스기는 정선석회암이 분포하는 석병산, 평창, 정선과 임계도폭, 화천리층이 분포하는 문경도폭, 그리고 황강리도폭 등디 해당한다 기타시대는 시대미상의 각력질 석회암과 상부석탄기의 홍점층군내 협재하는 결정질 석회암으로, 이들은 각각 정선도폭과 석병산도폭에 위치한다. 선캠브리아기, 시대미상, 캠브리아기 및 오오도비스기 대리석류의 물성 중에서 흡수율과 공극율은 선캠브리아기, 오오도비스기, 시대미상과 캠브리아기의 순으로 점차 감소한다. 이들의 공극율은 비중에 대하여 대체로 불규칙하며, 흡수율은 공극율에 대하여 거의가 뚜렷한 정의 상관관계를 이룬다. 압축강도는 공극율에 대하여 다소 불규칙한, 그리고 인장강도에 대하여 정의 상관관계를 이룬다. 그리고 마모경도는 압축강도와 인장강도에 대하여 대체로 뚜렷한 정의 경향을 각각 보인다. 이들 대리석류는 선캠브리아기 중경암-경암, 시대미상 중경암-경암, 캠브리아기 거의가 중경암-경암, 그리고 오오도비스기는 경암에 각각 해당한다.하고 구현 단계의 문제점들과 해결책을 기술한다. 다 솔레노이드방식 감압건조장치로 건조한 표고버섯으로 품위에 대한 유의성 검증결과, 표고버섯의 경우 온도별로는 색택과 복원률, 건조실 내부 압력별로는 수축률, 복원률에서 유의차가 있는 것으로 나타났다. 라. 본 연구에서 구명된 감압건조특성을 기초로 하여 배치식 감압건조기를 설계 제작에 활용하고자 한다.ational banks. Several financial interchange standards which are involved in B2B business of e-procurement, e-placement, e-payment are also investigated.. monocytogenes, E. coli 및 S. enteritidis에 대한 키토산의 최소저해농도는 각각 0.1461 mg/mL, 0.2419 mg/mL, 0.0980 mg/mL 및 0.0490 mg/mL로 측정되었다. 또한 2%(v/v) 초산 자체의 최소저해농도를 측정한 결과, B. cereus, L. mosocytogenes, E. eoli에 대해서는 control과 비교시 유의적인 항균효과는 나타나지 않았다. 반면에 S. enteritidis의 경우는 배양시간 4시간까지는 항균활성을 나타내었지만, 8시간 이후부터는 S. enteritidis의 성장이 control 보다 높아져 배양시간 20시간에서는 control 보다 약 2배 이상 균주의 성장을 촉진시켰다.차에 따른 개별화 학습을 가능하게 할 뿐만 아니라 능동적인 참여를 유도하여 학습효율을 높일 수 있을 것으로 기대된다.향은 패션마케팅의 정의와 적용범위를 축소시킬 수 있는 위험을 내재한

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남한강 유역의 범용토양유실공식(USLE)의 적용에 관한 연구

  • 이진영;양동윤;임현수;정공수;김주용
    • Proceedings of the KSEEG Conference
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    • 2003.04a
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    • pp.157-160
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    • 2003
  • 해마다 늘고 있는 토사유출희 인한 피해는 자연재해의 측면에서 매우 중요한 과제로 다루어지고 있으며, 토사유출에 의한 환경피해를 최소화하기 위해 토양유실량의 산정에 많은 연구가 진행되고 있다. 그러나 사면에서의 토양유실량 산정방법 및 산정된 결과에 대한 검증 역시 현실적으로 매우 어렵기 때문에 일반적으로 국내에서는 토양유실량산정을 위해 범용토양유실공식(Universal soil loss equation)을 사용하고 있다. 범용토양유실공식(USEL)은 실험적 근거가 미비한 국내실정에서 일반적으로 활용되고 있기 때문에 공식의 적용에 대한 다양한 실험적 연구가 필요하였다. 따라서 본 연구는 남한강 유역 여주-이포 구간을 대상으로 2002년 6월부터 2002년 10월까지 수행된 자연 상태에서의 토양침식실험과 실험지역의 USLE의 적용을 검토하였다. 토양침식실험을 통하여 산정된 침식율과 범용토양유실공식의 결과를 비교하였으며 USLE의 인자에 따른 토양유실량 산정 결과의 변화를 검토하고자 하였다. 남한강 유역에서의 토양침식 실험결과 자연 상태에서 연간토양유실량은 평균 12.54ton/acre/year이었으며, 최소 0.1ton/acre/year, 최대 34.06ton/acre/year로 나타났다. USLE에 의해 계산된 연간토양유실량은 17.15ton/acre/year로서 실험결과와는 많은 차이가 있었다. 이러한 차이는 토양유실량 산정에 필요한 다양한 조건을 정량화하는 과정에서 발생하는 것으로, USLE식에 활용되는 인자의 적용방법에 따라 커다란 차이를 보였다. 따라서 USLE에 의해 산정된 결과를 사용하기 위해서는 다양한 조건에 대한 검토가 이루어져야하며 USLE 산정에 관한 지속적인 실험적 연구가 이루어져야 하겠다. 증가할 것이다. 또한 부분육을 이용한 완전제품, 적색육제품, 유기농이나 별미식 제품과 같은 형태의 다양한 포장육 제품이 도입 될 것으로 생각되어진다.e in vitro SPF test method will be able to be used as an alternative method for in vivo SPF in case of lotion and cream. replica. A statistically significant improvement of Star Fruit Leaf Extract BG30-treated site was seen in decreased wrinkles. Star Fruit Leaf Extract BG30 results in clinically visible improvement in wrinkling when used topically for 5 weeks. 또한 관계마케팅, CRM 등의 이론적 배경이 되고 있는 신뢰와 결속의 중요성이 재확인하는 결과도 의의라고 할 수 있다. 그리고 신뢰는 양사 간의 상호관계에서 조성될 수 있는 특성을 가진 반면, 결속은 계약관계 초기단계에서 성문화하고 규정화 할 수 있는 변수의 성격이 강하다고 할 수가 있다. 본 연구는 복잡한 기업간 관계를 지나치게 협력적 측면에서만 규명했기 때문에 많은 측면을 간과할 가능성이 있다. 또한 방법론적으로 일방향의 시각만을 고려했고, 횡단적 조사를 통하고 국내의 한 서비스제공업체와 관련이 있는 컨텐츠 공급파트너만의 시각을 검증했기 때문에 해석에서 유의할 필요가 있다. 또한 타당성확보 노력을 기하였지만 측정도구 면에서 엄격한 개발과정을 준수하지는 못했다. 향후에는 모바일 컨텐츠 파트너의 기업의 특성을 조사하여 관계성 변수와의

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Effect of Soil Organic Matter on Arsenic Adsorption in the Hematite-Water Interface: Chemical Speciation Modeling and Adsorption Mechanism (비소의 적철석 표면 흡착에 토양유기물이 미치는 영향: 화학종 모델링과 흡착 기작)

  • Ko, Il-Won;Kim, Ju-Yong;Kim, Gyeong-Ung;An, Ju-Seong;Davis, A. P.
    • Economic and Environmental Geology
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    • v.38 no.1
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    • pp.23-31
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    • 2005
  • This study was performed to investigate the effect of humic acid on the adsorption of arsenic onto hematite and its binding mechanism through the chemical speciation modeling in the binary system and the adsorption modeling in the ternary system. The complexation modeling of arsenic and humic acid was suitable for the binding model with the basis of the electrostatic repulsion and the effect of bridging metal. In comparison with the experimental adsorption data in the ternary system, the competitive adsorption model from the binary intrinsic equilibrium constants was consistent with the amount of arsenic adsorption. However, the additive rule showed the deviation of model in the opposite way of cationic heavy metals, because the reduced organic complexation of arsenic and the enhanced oxyanionic competition diminished the adsorption of arsenic. In terms of the reaction mechanism, the organic complex of arsenic, neutral As(III) and oxyanionic As(V) species were transported and adsorbed competitively to the hematite surface forming the inner-sphere complex in the presence of humic acid.

Distribution Characteristics of Quaternary Geology and Aggregate Resources in Geumsan-gun, Chungcheongnam-do (충청남도 금산군 일대 제4기 지질 및 골재자원 분포 특성)

  • Kim, Jin Cheul;Kim, Ju Yong;Lee, Jin-Young
    • Economic and Environmental Geology
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    • v.54 no.5
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    • pp.595-603
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    • 2021
  • Sand layer distribution, which is the main target of river and land aggregate resources, mainly belongs to alluvial and river sedimentary environments among the Quaternary sedimentary environments. The distribution of aggregate resources in the area of Geumsan-gun, Chungcheongnam-do is characteristically developed around a sedimentation environment in which intrusive meandering river dominate. Although the area around Bonhwangcheon Stream and the area near the confluence of small streams are small, the river floodplain develops and corresponds to the aggregate distribution area. The sedimentary layer formed in the sedimentary environment such as colluvial deposits or alluvial fan deposits has a relatively low distribution rate of aggregate resources. The vertical distribution of the Quaternary sedimentary layers in the Geumsan-gun region ranges from about 5 to 12 m and has an average Quaternary sedimentary thickness of 8 m. The aggregate-bearing section has an average thickness of 3.6 m, and the average grain size is about 21% clay-silt, 67% sand, and 12% gravel. The main characteristics of the aggregate-bearing section are that coarse-grained sand predominates, and gravel is sub-angular or sub-rounded, and the sorting is generally poor and has a massive form of deposits, and the soil colour ranges from dark grey to yellowish-brown. In Geumsan-gun, the most likely distribution area for aggregate development is the alluvial sedimentary and river sedimentary layers distributed along the current and former riverbeds of the main Geumgang River, Bonhwangcheon and small River tributaries.