• Membrane Journal
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• v.24 no.1
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• pp.39-49
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• 2014

The effects of pH and oxygen back-flushing were investigated in hybrid process of ceramic microfiltration and PES (polyethersulfone) beads loaded with titanium dioxide ($TiO_2$) photocatalyst for advanced drinking water treatment in viewpoints of membrane fouling resistance ($R_f$), permeate flux (J), and total permeate volume ($V_T$). As increasing pH, $R_f$ decreased and J increased. Finally the maximum $V_T$ could be acquired at pH 9. Treatment efficiencies of turbidity was almost same independent of pH. Treatment efficiency of dissolved organic matters (DOM) decreased as increasing pH. As results of comparing the oxygen and nitrogen back-flushing, $R_{f,180}$ at oxygen back-flushing was the lower than that at nitrogen back-flushing, and the dimensionless final permeate flux ($J_{180}/J_0$) by initial permeate flux ($J_0$) at oxygen back-flushing was maintained the higher than that at nitrogen back-flushing except 10 and 12 min of back-flushing period (FT). Treatment efficiency of turbidity at oxygen back-flushing was a little higher than that at nitrogen back-flushing. Treatment efficiency of the DOM at nitrogen back-flushing was the higher than that at oxygen back-flushing. Also, treatment efficiency of turbidity at saturated oxygen was similar with those of oxygen and nitrogen back-flushing, but the treatment efficiency of DOM was increased significantly because OH radical could be generated by reaction between saturated oxygen and photocatalyst.

• Proceedings of the Korean Information Science Society Conference
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• 2003.04a
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• pp.572-574
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• 2003

XML은 반 구조 데이터(semi-structured data)의 일종으로 데이터들이 정형화된 구조를 가지고 있지 않다는 것이 특징이다. 기존의 데이터베이스 시스템은 고정된 스키마를 통해 데이터를 저장 관리하기 때문에 정형화된 구조를 가지지 않는 XML 문서를 저장하기에는 한계가 있다. 본 논문에서는 정형화된 구조를 가지지 못하는 XML문서를 효과적으로 저장하고 관리할 수 있는 저장장치를 구현하고 구현 사항에 대해 설명한다. 본 논문의 저장 장치는 XML을 DOM트리로 표현한 후 DOM트리의 각 노드를 객체로 만들어 저장한다. 본 논문의 저장 장치는 다중 사용자를 지원하기 위해 클라이언트 서버 구조로 구성되어 있으며 각 객체는 전용 파일, 관계형 시스템의 LDB등 다양한 하부 구조에 저장될 수 있다.

• Korean Institute of Interior Design Journal
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• v.27 no.2
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• pp.196-203
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• 2018

The background of this study was the fact that the religious spaces require sacred space devices in addition to aesthetic aspects. This study began with the definition that 'philosophical phenomenology provides one of the theoretical frameworks for religious phenomenology'. Seeing that 'philosophical phenomenology has limitations in drawing out the characteristics, this study attempted to study religious spaces through the method of specialized and refined religious phenomenology for the religious spaces alone. The purpose of this study was to understand the characteristics of religious spaces and the fact that the religious spaces are divided into 'profane' domains and 'sacred' ones and to analyze the characteristics of space and light in terms of religious phenomenology through Dutch religious architect Dom Hans van der Laan's architectural projects of monasteries. The study method was to present the relationship between space and light in terms of religious phenomenology and to summarize Van der Laan's interpretational method of the religious spaces through the architect's life and architectural philosophy.The conclusion of this study was that Dom Hans van der Laan's entire works were judged to have sufficient research value in studying the religious spaces as they were all created in the special category of 'religion'. With his project, it is possible for us to study 'hierophany' as experience of space and light through the methodology of religious phenomenology. This study has significant meaning in that it introduced an architect of religious spaces and a related new view on architecture.

• Tunnel and Underground Space
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• v.14 no.6 s.53
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• pp.391-398
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• 2004

An algebraic algorithm for predicting the joint trace distribution on the cut-face of rock slope based on the orientations and the locations of joints investigated in the borehole has been developed. Joint trace prediction is manipulated by utilizing the three dimensional plane equations of both joint planes and projection face, and the extent of trace within the projection area is calculated by considering the persistence of each joint plane. Joint trace prediction method is efficiently applied for analyzing the stability and the adequacy of support design of Gimhae Naesam cut-slope, which is structurally unstable due to slumping. Structural characteristics of rock mass is investigated by performing DOM drilling and the potential rock mass sliding inside slope face is analyzed by examining the orientations of joint planes which can induce the slope failure. Also, the efficiency of anchor support design is evaluated by considering the joint trace distribution on the anchor installation area and its sliding potential.

• Journal of Korea Water Resources Association
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• v.39 no.6 s.167
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• pp.511-520
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• 2006

Riverbank filtration is a natural process, using alluvial aquifers to remove contaminants and pathogens in river water for the production of drinking water. In Korea, most of the drinking water is supplied by surface water in-take. However, maintaining the quality of the drinking water becomes more and more difficult due to the increase of contamination. In riverbank filtration, the understanding of contaminant transport is an important task for the production of high quality drinking water and for the maintenance of facilities. In this paper, the transport behavior of hydrophobic organic contaminants is investigated when contaminants coexist with dissolved organic matter (DOM) and bacteria. In the developed model, the aquifer is thought of as a four phase system: two mobile colloidal phases, an aqueous phase, and a stationary solid matrix phase. The model equations are solved numerically for various situations. Results indicate that the presence of colloidal matters can enhance the mobility of contaminant significantly and that partitioning coefficients play an important role in the process.

• Journal of the Korea Computer Industry Society
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• v.2 no.6
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• pp.775-782
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• 2001

Until recently Web retrieval engine has presented a demanded document to users according to the amount and the frequency of inquired key words in each document under the assumption that the more key words a document has, the more accessible it is. This method of searching doesn't matter to a normal document such as HTML Web data in which structural information is not involved. However, Web data realized in XML contains structural information and modeling of graphic forms is also available. Therefore, in the case of XML, this method leads to no less trouble since it depends only on the frequency of key words. We consider that this problem can be resolved by way of inquiry which is similar to SQL. This form of inquiry enables us to snatch an exact data we want in a quick and clear way with a full advantage of structural quality of XML, overcoming the shortcomings of frequency-based engine. In this paper, We aim to design a model of information retrieval system of XML data using XML DOM and consider its algorithm related with it.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.17 no.8
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• pp.1851-1856
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• 2013

An XML is widely used for web services, such as SOAP(Simple Object Access Protocol) and REST (Representational State Transfer), and also de facto standard for representing data. Since the XML parser using DOM(Document Object Model) requires a preprocessing task creating a DOM-tree, and then storing it into memory, embedded systems with limited resources typically employ a streaming XML parser without preprocessing. In this paper, we propose a new architecture for the streaming XML parser using an APSearch(Adaptive Parallel Search) on FPGA(Field Programmable Gate Array). Compared to other approaches, the proposed APSearch parser dramatically reduces overhead on the software side and achieves about 2.55 and 2.96 times improvement in the time needed for an XML parsing. Therefore, our APSearch parser is suitable for systems to speed up XML parsing.

• Safety and Health at Work
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• v.10 no.2
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• pp.196-204
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• 2019

Background: Liquid chromatography-tandem mass spectrometry (LC-MSMS) for simultaneous analysis of multiple microbial secondary metabolites (MSMs) is potentially subject to interference by matrix components. Methods: We examined potential matrix effects (MEs) in analyses of 31 MSMs using ultraperformance LC-MSMS. Twenty-one dust aliquots from three buildings (seven aliquots/building) were spiked with seven concentrations of each of the MSMs ($6.2pg/{\mu}l-900pg/{\mu}l$) and then extracted. Another set of 21 aliquots were first extracted and then, the extract was spiked with the same concentrations. We added deepoxy-deoxynivalenol (DOM) to all aliquots as a universal internal standard. Ten microliters of the extract was injected into the ultraperformance LC-MSMS. ME was calculated by subtracting the percentage of the response of analyte in spiked extract to that in neat standard from 100. Spiked extract results were used to create a matrix-matched calibration (MMC) curve for estimating MSM concentration in dust spiked before extraction. Results: Analysis of variance was used to examine effects of compound (MSM), building and concentration on response. MEs (range: 63.4%-99.97%) significantly differed by MSM (p < 0.01) and building (p < 0.05). Mean percent recoveries adjusted with DOM and the MMC method were 246.3% (SD = 226.0) and 86.3% (SD = 70.7), respectively. Conclusion: We found that dust MEs resulted in substantial underestimation in quantifying MSMs and that DOM was not an optimal universal internal standard for the adjustment but that the MMC method resulted in more accurate and precise recovery compared with DOM. More research on adjustment methods for dust MEs in the simultaneous analyses of multiple MSMs using LC-MSMS is warranted.

• The Journal of Information Technology and Database
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• v.7 no.2
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• pp.17-32
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• 2000

As XML emerging as the Internet electronic document language standard of the next generation, the number of XML documents which contain vast amount of Information is increasing substantially through the transformation of existing documents to XML documents or the appearance of new XML documents. Consequently, XML document retrieval system becomes extremely essential for searching through a large quantity of XML documents that are storied in and managed by DBMS. In this paper we describe the design and implementation of BADA-IV/XML query processor that supports content-based, structure-based and attribute-based retrieval. We design XML query language based upon XQL (XML Query Language) of W3C and tightly-coupled with OQL (a query language for object-oriented database). XML document is stored and maintained in BADA-IV, which is an object-oriented database management system developed by ETRI (Electronics and Telecommunications Research Institute) The storage data model is based on DOM (Document Object Model), therefore the retrieval of XML documents is executed basically using DOM tree traversal. We improve the search performance using Node ID which represents node's hierarchy information in an XML document. Assuming that DOW tree is a complete k-ary tree, we show that Node ID technique is superior to DOM tree traversal from the viewpoint of node fetch counts.

• Journal of Korean Society on Water Environment
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• v.30 no.6
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• pp.605-611
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• 2014

This research was carried out to examine the concentration and fate of dissolved organic matter due to the increased detention time in middle and down stream of the Nakdong River. Aldo the characteristics of biodegradation of DOM were investigated according to the various water sources. The approaches used to characterize DOM biodegradability include the changes in DOC concentration and DOM fraction. Long-term biodegradation test for each organic source was also conducted. As the result, maximum 50% of DOC was reduced during the first 30 days of biodegradation tests. After 30 days, biodegradation of organic matter was continuously progressed, as showing continuous reduction of DOC. While DOC concentration was reduced, SUVA values for the organic matters were increased. Properties of dissolved organic matter by water sources also showed decreasing hydrophilic components while showing increased hydrophobic components. The more rapid reduction of the hydrophilic components than hydrophobic components might be due to the preferential degradation of the hydrophilic components by microorganisms during biodegradation process.