• Proceedings of the Korea Water Resources Association Conference
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• 2018.05a
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• pp.228-228
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• 2018

강변여과는 지하수 인공함양 방식 중 유도함양(induced recharge) 또는 간접함양 방식에 속한다. 이는 하천 및 강변 부근에 집수시설을 설치한 후, 미고결층 대수층(unconsolidated aquifer)의 자연 오염 저감능을 이용하여 지표수를 간접 취수하는 방식으로 수질이 불량한 지표수가 대수층을 관류하면서 희석, 화학적 이온 교환 및 반응, 흡착, 생물막(biofilm; 미생물에 의한 자연저감), 여과 등을 통하여 수질이 개선된다. 강변여과수내의 용존 농도가 높은 철과 망간은 수처리 비용증가, 용수관정 및 시설물의 수명단축을 초래한다. 따라서 강변여과 지역의 미고결 대수층에서 효과적인 철과 망간 동시 제거(vyredox)를 위해 에어서징(air surging)과 블록 서징(block surging)을 실시하기 위해서 실내 물탱크 모델(water tank model)에서 에어서징에 따른 공기 순환 우물시스템을 관찰하였으며, 이를 바탕으로 현장시험(Test bed)에 적용하였다. 미고결 대층수층에서의 철 망간은 음용수 기준치(각각 0.3 mg/L)를 초과하고 있으며, 강변여과 취수 개발 및 이용을 제한하는 요인이 되고 있다. 본 연구에서 사용된 에어서징과 블록서지 기술은 자갈층 및 미고결 대수층에 충진된 슬라임 및 폐색(clogging)을 제거함과 동시에 관정 주변의 대수층의 투수성 개선과 산화환경으로 치환되며, 대수층에 잔존하는 철/망간의 산화물들을 관정내로 빼낼 수 있는 방법이다. 따라서 서징에 따른 폐색 제거효율을 검토한 결과에서 철 망간 이온농도 저감효과와 관정 주변의 수리전도도(hydraulic conductivity) 및 저류계수(coefficient of storage)가 증가한 것으로 나타났다. 이와 같이 강변여과에 의한 폐색은 미고결층내 공기주입 및 블록서지를 통하여 철/망간 이온농도 저감 및 수리특성 개선 효과에 유용한 것으로 평가된다.

• Journal of the Korean Society for Library and Information Science
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• v.30 no.1
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• pp.3-18
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• 1996

This article analyzes the record structure, content designation, and the content of UNIMARC, USMARC, and KORMARC formats for authorities, through the comparative investigation, Structure and content designation are almost same with those of the bibliographic formats, being based on those of ISO 2709. The data fields of USMARC and KORMARC are divided into blocks based on the traditional authority card formats, and those of UNIMARC are divided into functional blocks based on the GARE. Record contents of the formers in the fixed-length fields include more elements on the selectioa status and scope of the heading, and those related to the series. And those of the later include more elements for the international exchange. Based on the analysis of the variable fields, it is recommended that KORMARC should include an additional subfield, say $(\blacktriangledown\;j)$ for the processing of the Hanja(Chinese character) data and add the separate classification fields for series.

• Journal of the Korean Society for Library and Information Science
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• v.33 no.3
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• pp.63-86
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• 1999

This article investigates the general characteristics and developments of the MARC format for holdings data. It also analyzes the record structure, content designation, and the content of it, mainly based on USMARC and KORMARC formats. Structure and content designation of them are almost same with those of the bibliographic and authority formats. The data fields divided into functional blocks based on their functions, but only 0XX, 5XX, 8XX fields are used in the holdings formats. Record contents of the data in the 008 fields include more elements related to the holdings and acquisition information. Variable fields can be grouped into several blocks, including those for numbers and codes; for notes fields, for location , and for holdings data. Holdings data fields include caption and pattern fields, enumeration and chronology fields, textual holdings fields, and item information fields. This article analyzes the content in each data fields in detail.

• The Journal of Engineering Geology
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• v.19 no.3
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• pp.389-400
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• 2009

Iron and manganese contents are usually over the limit of drinking water standard (0.3 mg/L) in unconsolidated aquifer of river bank filtration site in Nakdong river. Surge block and air surging techniques used in this study are useful tools to remove the slime within gravels and pebbles, to increase permeability of aquifer, to provide oxygen into aquifer, and to discharge iron and manganese oxides from a well. Surging activity brought about $5{\sim}8$ and $5{\sim}9$ times decreases in $Fe_{(total)}$ and $Fe^{2+}$ contents, and also 10 times decrease in $Mn^{2+}$ contents compared to non-surging condition, respectively. Additionally, iron oxide and manganese oxide increased up $1{\sim}1.2$ times after surging. This result shows that air injection into the aquifer can help iron and manganese content decreased and in-situ treatment technology needs to be introduced in river bank filtration project in South Korea.

• Journal of Information Management
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• v.21 no.2
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• pp.9-23
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• 1990

CD-ROM technique, not more than 10 years after development, goes through rapid growth, has been taken advantage of several practical application parts. Needless to say about bibliographic data, numeric value, the phonetics, an image and a picture data that are recorded as abstract or full text, and offered and applied to industry, information service including library, it can be used for library staffs, information retrieval. Escape from the need of one disc drive and one computer to access one disc, now we organize an ideal system that can be retrieved several CD-ROM used only one drive, several users can access several information, so networking is possible through LAN. In this article, we studied the function and type, characteristics, system, structure, data block, production procedure, standardization of CD-ROM LAN.

• Journal of the Korean Society for Library and Information Science
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• v.33 no.1
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• pp.87-111
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• 1999

This article investigates the functions, needs, and developments of the MARC format for classification data. and recommends the development for the KORMARC format for classification data. It ae analyzes the record structure, content designation and the content of it mainly based on USMARC format. Structure and content designation are almost same with those of the bibliographic and authority formats. The data fields divided into functional blocks based on their functions. Record contents of the data in the fixed-length fields include more elements on the classification numbers, including type of number, classification validity, standard or optional number, synthesized number. Variable fields can be grouped into several blocks, inducing those for numbers and codes: for classification numbers and terms; for references and tracings; for notes fields: for index terms fields, and for number building fields. Data in each fields of this format have the same contents with those in other related fields as soon as possible. This article analyzes the content in each data fields in detail.

• Journal of The Korean Society of Agricultural Engineers
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• v.53 no.2
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• pp.75-82
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• 2011

This study was performed to evaluate the water purification properties of bio-composites planting blocks using oyster shell and effective microorganism that have high absorption ability of heavy metals and organics to develop environmentally friendly river embankment technique contained various factors such as oyster shells, effective microorganism, porous concrete and planting embankment block. To maximize greening effect, the seeds were arbitrarily sown. In addition, in order to analyze the effect of water quality purification after the planting, the samples were collected from each designated zone 1, 7 and 30 days after steeping in water. Then, the samples were analyzed in terms of seven test items such as SS, BOD, COD, T-N, T-P, pH, etc. on the basis of the test method for water pollution. The following conclusions were reached from the test result. As a result of analysis for water quality purification for the concrete block containing the effective microorganism, it was found that the values for SS, BOD, T-N and T-P for the sample taken after 30 days were lower than the initial values, which indicated that the water purification effect had been created. The result of the water quality purification analysis for the concrete block containing oyster shell showed that the values for SS, BOD, COD and T-P for the sample taken after 30 days were lower than the initial values which also indicated that it had been effective in water quality purification.

• The Journal of Engineering Geology
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• v.22 no.1
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• pp.27-37
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• 2012

To investigate the effect of aquifer disturbance on hydraulic properties while well drilling at unconsolidated aquifer, the following tests were conducted: the surge block and air-surging methods, which are well development methods used after well drilling; and step-drawdown tests and constant-rate pumping tests, which are used to assess changes in the aquifer after well drilling and development. The result of step-drawdown tests indicated that drawdown for a pumping-rate of $700m^3/day$ was 21.62 m after well development, decreasing 4.39 m from 26.01 m after well drilling. The skin factor used to identify the well properties decreased from 7.92 after well drilling to 5.04 after well development, respectively, which shows the improvement of well. Constant-rate pumping tests revealed a small increase in aquifer transmissivity after well development at MW-2, -3, and -4, centering around pumping well, from $1.684{\times}10^{-3}{\sim}4.490{\times}10^{-3}m^2/sec$ to $4.002{\times}10^{-3}{\sim}4.939{\times}10^{-3}m^2/sec$. MW-1, however, showed decline in hydraulic conductivity from $1.018{\times}10^{-2}m^2/sec$ to $6.988{\times}10^{-3}m^2/sec$, which was caused by a small decrease of aquifer permeability around monitoring well MW-1 due to latent factor of air interception and clogging in aquifer during surging. This finding indicates that fine particles have an effect on hydraulic properties at unconsolidated aquifers during well drilling; therefore, we consider that well drilling and development have an effect on hydraulic properties.