A Novel Method for Investigating the Influence of Feed Water Recovery on Colloidal and NOM Fouling of RO and NF Membranes

Lee, Sangyoup,Cho, Jaeweon,Elimelech, Menachem Mary Ann Liebert 2005 ENVIRONMENTAL ENGINEERING SCIENCE Vol.22 No.4

中部地域 環濠遺蹟에 대한 一檢討

李尙燁(Sangyoup Lee) 중부고고학회 2006 고고학 Vol.5 No.1

환호는 최근까지 대부분 영남지방을 중심으로 확인되었으나, 조사의 증가에 따라 중부지역에서도 다수 확인되었다. 따라서 중부지역에서 환호 중 안성 반제리유적의 환호를 중심으로 그 기능을 살펴보고자 하였다. 환호는 전세계적으로 분포하고 있으며, 시기적으로는 신석기시대 이후부터 출현하고 있는데, 대부분은 주거지와 동반되는 것이 일반적 현상이다. 이러한 환호의 기능에 대해 대부분 방어ㆍ경계ㆍ의례를 위해 조성된 것으로 이해하고 있다. 중부지역에서 확인된 환호는 안성 반제리유적ㆍ부천 고강동 적석유구ㆍ화성 동탄 동학산유적ㆍ오산 가장동유적ㆍ부여 송국리유적ㆍ청원 대율리유적ㆍ강릉 방동리유적 등이며, 입지를 통해 산정형과 구릉형, 형태를 통해 테뫼형 환호와 포곡형 환호로 구분할 수 있다. 안성 반제리유적에서 확인된 환호는 입지상 산정형, 형태상 태뫼형에 해당된다. 환호의 내부에는 환호가 처음 사용되었던 시기의 주거지가 확인되지 않으며, 정상부에 비교적 큰 규모의 바위가 자리하고 있다. 한편 환호는 기능이 상실됨에 따라 폐기되었으며, 이후 환호 내부 또는 환호를 파괴하고 초기철기시대의 주거지가 조성되었다. 안성 반제리유적 환호의 사용시기는 환호의 퇴적토에서 출토된 유물 원형정토대토기와 두형토기 등을 통해 B.C. 5세기에 처음 조성되었던 것으로 추정되며, 정확한 폐기 시기는 알 수 없는 실정이다. 한편 환호 폐기 후 조성된 주거지 출토유물 중 구연의 단면이 원형에서 방형으로 변화되는 토기를 통해 반제리유적은 B.C. 2세기 이전에 폐기된 듯하다. 환호의 기능은 초축시 내부에 생활과 관련된 공간인 주거지가 확인되지 않아 환호의 제기능 중 儀禮 즉, 祭儀의 기능을 수행하였던 것으로 추정하였다. Ditches were discovered around the yeongnam area until a recent date but discovered around the middle area by increased research. So we will inspect the function of ditches of the Ban je-ri ruins among ditches of the middle area. Ditches are distributed all over the world. It appeared after the New Stone Age and most of it usually be accompanied with habitation site. We understand that the function of ditches is for defense, precaution and ceremony. Ditches which were discovered around the middle area are the Ban je-ri ruins in the Anseong city, the Jeokseok synonymous phrase in the Gokang-dong. Bucheon city, the Donghak mountain ruins in the Dongtan. Hwaseong city, Gajang-dong ruins in the Osan city. Songguk-ri ruins in the Buyeo-gun, Bangdong-ri ruins in the Gangneung city, And that is classified a mountaintop type and hill type by location and a headband type and pile up block shape. Ditches were discovered in the Ban je-ri. Anseong city is a mountaintop type by location and a headband type by shape. The habitation site where was used at first stage wasn’t discovered in the inside of ditches and there is relatively big rock in the top. On the other hand ditches were disused by losing function. Then the habitation of the first Iron Age was formed after destroying the ditches or inside of ditches. We presumed the used time of the ditches of Ban je-ri. Anseong city is B.C. 5th century through bowl with round clay stripe and mounted dish from a sedimentary soil of the ditches. Disused time is unknown but we presumed the disused time is before B.C. 2nd century through dish section was changed to square shape from round shape among excavated ruins on the habitation which was formed afterdisusing ditches. We presumed that function or ditches is ceremony because the habitation where is a space in relation to life wasn’t discovered when it was under construction.

지방관리도로 교통사고 감소를 위한 마을보호구역 정책제안: 전라북도를 중심으로

김상엽(KIM, Sangyoup) 대한교통학회 2020 교통 기술과 정책 Vol.17 No.6

Measurements of assimilable organic carbon (AOC) in high saline conditions using P17

Mun, Eunjeong,Lee, Sangyoup,Kim, Inhyuk,Kwon, Boksoon,Park, Heedueng,Hong, Seungkwan IWA Publishing 2013 WATER SCIENCE AND TECHNOLOGY -WATER SUPPLY- Vol.13 No.2

sion='1.0' encoding='utf-8'?><!DOCTYPE article PUBLIC '-//NLM//DTD Journal Publishing DTD v2.3 20070202//EN' 'journalpublishing.dtd'><article article-type='research-article' xmlns:xlink='http://www.w3.org/1999/xlink'><front><journal-meta><journal-id journal-id-type='pmc'>ws</journal-id><journal-id journal-id-type='pubmed'>WS</journal-id><journal-id journal-id-type='publisher'>Water Science & Technology: Water Supply</journal-id><issn pub-type='ppub'>1606-9749</issn><publisher><publisher-name>IWA Publishing</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type='doi'>10.2166/ws.2013.019</article-id><article-id pub-id-type='other'>jWSTWS.v13.i2.pg265</article-id><article-categories><subj-group><subject>Research Article</subject></subj-group></article-categories><title-group><article-title>Measurements of assimilable organic carbon (AOC) in high saline conditions using P17</article-title></title-group><contrib-group><contrib contrib-type='author' rid='aff1'><name><surname>Mun</surname><given-names>Eunjeong</given-names></name><xref ref-type='aff' rid='aff1'></xref></contrib><contrib contrib-type='author' rid='aff1'><name><surname>Lee</surname><given-names>Sangyoup</given-names></name><xref ref-type='aff' rid='aff1'></xref></contrib><contrib contrib-type='author' rid='aff1'><name><surname>Kim</surname><given-names>Inhyuk</given-names></name><xref ref-type='aff' rid='aff1'></xref></contrib><contrib contrib-type='author' rid='aff2'><name><surname>Kwon</surname><given-names>Boksoon</given-names></name><xref ref-type='aff' rid='aff2'></xref></contrib><contrib contrib-type='author' rid='aff1'><name><surname>Park</surname><given-names>Heedueng</given-names></name><xref ref-type='aff' rid='aff1'></xref></contrib><contrib contrib-type='author' rid='aff1'><name><surname>Hong</surname><given-names>Seungkwan</given-names></name><xref ref-type='aff' rid='aff1'></xref></contrib><aff id='aff1'>School of Civil, Environmental & Architectural Engineering, Korea University, 1, 5-ga, Anam-Dong, Sungbuk-Gu, Seoul, 136-713, Korea E-mail: <email>skhong21@korea.ac.kr</email></aff><aff id='aff2'>Environment G. Emerging Tech, Center/SAIT Samsung Electronics, Korea</aff></contrib-group><volume>13</volume><issue>2</issue><fpage>265</fpage><lpage>272</lpage><history><date date-type='received'><day>30</day><month>4</month><year>2012</year></date><date date-type='accepted'><day>6</day><month>9</month><year>2012</year></date></history><permissions><copyright-statement>© IWA Publishing 2013</copyright-statement><copyright-year>2013</copyright-year></permissions><abstract ><P>Biofouling caused by the deposition or growth of microorganisms on the membrane surface is one of the major concerns in nanofiltration (NF) and reverse osmosis (RO) processes. Assimilable organic carbon (AOC) has been a useful index to assess the growth potential of bacteria. In the case of drinking water, the AOC assay method has been widely applied to estimate growth or regrowth potential of bacteria in distribution and storage systems. However, studies on AOC measurement for high salinity water samples such as brackish water and seawater are rather scarce. The objective of this research is to investigate the influence of water salinity on the conventional AOC assay method. AOC samples with different salt concentrations were prepared by varying NaCl concentration from 0 to 35,000 mg/L, while the acetate concentration was held at 100 μg/L. The number of cells produced in water samples was measured by the heterotrophic plate count (HPC) method using R2A agar. The result showed that the cell production of <I>Pseudomonas fluorescens</I> strain P17 and <I>Spirillum</I> strain NOX decreased with increasing salinity. Especially, the growth of <I>Spirillum</I> strain NOX was noticeably influenced by water salinity. To further observe the relation between acetate concentration and cell production in high salinity water, organic-free saline water

Influence of solution chemistry on the surface heterogeneity of reverse osmosis membrane

Kim, Youngjin,Lee, Sangyoup,Hong, Seungkwan Balaban Publishers 2012 Desalination and Water Treatment Vol.43 No.1

<P> The chemical heterogeneity of reverse osmosis membrane surface and its impacts on membrane fouling were investigated using dynamic hysteresis, which is a newly developed surface analytical technique. Based on dynamic hysteresis measurements, it has been demonstrated that the chemical heterogeneity of membrane surface was greatly influenced by solution?pH and ionic strength. Significant variation of dynamic hysteresis was observed as solution pH changed, implying the alteration of membrane surface heterogeneity. Interestingly, there existed the interplay between chemical and physical surface heterogeneity with respect to solution ionic strength. At low ionic strength, dynamic hysteresis mostly reflected chemical surface heterogeneity, while physical surface heterogeneity played more dominant role in the change of dynamic hysteresis with increasing ionic strength. This implies that membrane fouling due to chemical surface heterogeneity of the membrane is less remarkable in seawater desalination compared to wastewater and brackish water treatments. In addition, mechanisms and factors affecting chemical and physical surface heterogeneity and their interplay with respect to solution chemistry including pH, ionic strength and divalent cation concentration are discussed and elucidated. </P>

Preparation of Fluorous Solvent-Dispersed Fe₃O₄ Nanocrystals: Role of Oxygen in Ligand Exchange

Kim, Youngsun,Lee, Sangyoup,Kim, Sehoon American Chemical Society 2016 Langmuir Vol.32 No.14

<P>Perfluorinated ligand-passivated Fe3O4 nanocrystals were prepared through a biphasic ligand exchange method. It was found that dissolved oxygen in the reaction media predominantly determined the degree of ligand exchange and the resultant dispersion property of nanocrystals in a fluorous solvent. X-ray photoelectron spectroscopic analyses revealed that dissolved oxygen molecules bind to the surface iron species of nanocrystals in competition with the carboxylate moiety of ligands during the exchange reaction, lowering the degree of ligand exchange and colloidal stability significantly. Reducing the oxygen content of the fluorous phase by N-2 bubbling was found to result in a highly stable dispersion of phase-transferred Fe3O4 nanocrystals with a single-particle size distribution maintained for a few months.</P>

블록체인기반 무인무기체계 피아식별 방안

최대윤(Daeyoon Choi),이상엽(Sangyoup Lee),신인철(Incheol Shin) 대한전자공학회 2022 대한전자공학회 학술대회 Vol.2022 No.6

자동변속기유의 마찰 및 점도 특성이 연비향상에 미치는 영향에 대한 연구

유성춘(Sungchoon Yoo),차상엽(Sangyoup Cha) 한국자동차공학회 2006 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-

To reduce viscosity to be related to the flow resistance or to improve the friction property of automatic transmission fluid is one of the effective way to improve fuel economy of motor vehicle. This study shows that automatic transmission fluid to have a lower viscosity contribute to improve the fuel economy because reduce the torque loss and improve the transmittal efficiency, While Friction property did not help to improve the transmittal efficiency in the automatic transmission. Also, shows F/F type transmission is more affected by viscosity of ATF than F/R type transmission.

Application of osmotic backwashing in forward osmosis: mechanisms and factors involved

Kim, Changwoo,Lee, Sangyoup,Hong, Seungkwan Informa UK (Taylor Francis) 2012 Desalination and Water Treatment Vol.43 No.1

Dielectrophoresis-magnetophoresis force driven magnetic nanoparticle movement in transformer oil based magnetic fluids.

Lee, Jong-Chul,Lee, Sangyoup American Scientific Publishers 2013 Journal of Nanoscience and Nanotechnology Vol.13 No.9

<P>Magnetic fluid is a stable colloidal mixture contained magnetic nanoparticles coated with a surfactant. Recently, it was found that the fluid has properties to increase heat transfer and dielectric characteristics due to the added magnetic nanoparticles in transformer oils. The magnetic nanoparticles in the fluid experience an electrical force directed toward the place of maximum electric field strength when the electric field is applied. And when the external magnetic field is applied, the magnetic nanoparticles form long chains oriented along the direction of the field. The behaviors of magnetic nanoparticles in both the fields must play an important role in changing the heat transfer and dielectric characteristics of the fluids. In this study, we visualized the movement of magnetic nanoparticles influenced by both the fields applied in-situ. It was found that the magnetic nanoparticles travel in the region near the electrode by the electric field and form long chains along the field direction by the magnetic field. It can be inferred that the movement of magnetic nanoparticles appears by both the fields, and the breakdown voltage of transformer oil based magnetic fluids might be influenced according to the dispersion of magnetic nanoparticles.</P>