• The Journal of the Korea Contents Association
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• v.9 no.10
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• pp.122-129
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• 2009

MMORPG Quest plays a strong role of motivation through compensation related with Avatar such as items and experience points rather than a role of story transfer. This situation finally made MMORPG become a difficult game that players should study the compensation of Quest for growth of a character, so it causes fixation of the user class. As a solving method of the fixation of the users, the possibility of Quest capable of strengthening play motive of various users through clarification of motivation structure of the Quest play and pluralistic understanding about players was investigated. This is a direct response to the user within the game system or how to use the player log information. The pluralistic understanding method of players will have values as a tool that can guarantee the objectivity and actual production of the data collected utilizing.

• Journal of Microbiology and Biotechnology
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• v.17 no.11
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• pp.1789-1796
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• 2007

A ${\beta}$-glucosidase with the molecular mass of 160,000 Da was purified to homogeneity from cell extract of a cellulolytic bacterium, Cellulomonas uda CS1-1. The kinetic parameters ($K_m$ and $V_{max}$) of the enzyme were determined with pNP-cellooligosccharides (DP 1-5) and cellobiose. The molecular orbital theoretical studies on the cellulolytic reactivity between the pNP-cellooligosaccharides as substrate (S) molecules and the purified ${\beta}$-glucosidase (E) were conducted by applying the frontier molecular orbital (FMO) interaction theory. The results of the FMO interaction between E and S molecules verified that the first stage of the reaction was induced by exocyclic cleavage, which occurred in an electrophilic reaction based on a strong charge-controlled reaction between the highest occupied molecular orbital (HOMO) energy of the S molecule and the lowest occupied molecular orbital (LUMO) energy of the hydronium ion ($H_3O^+$), more than endocyclic cleavage, whereas a nucleophilic substitution reaction was induced by an orbital-controlled reaction between the LUMO energy of the oxonium ion ($SH^+$) protonated to the S molecule and the HOMO energy of the $H_2O_2$ molecule. A hypothetic reaction route was proposed with the experimental results in which the enzymatic acid-catalyst hydrolysis reaction of E and S molecules would be progressed via $SN_1$ and $SN_2$ reactions. In addition, the quantitative structure-activity relationships (QSARs) between these kinetic parameters showed that $K_m$ has a significant correlation with hydrophobicity (logP), and specific activity has with dipole moment, respectively.

• Journal of the Korean Society for information Management
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• v.37 no.2
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• pp.171-195
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• 2020

This study analyzed the collaborative process in time series by dismantling the edit log big data of Wikipedia Korea, a representative online collaboration community, from early 2002 to 2019. Analysis elements were extracted from the document edit records, formatted in standardized XML, and analyzed using Python and R. The ways of editors' contribution, the characteristics of data contents, and the trend of document creation were explained by the analysis. An active contribution of a small set of editors and a loose participation of the majority were revealed. In addition, sociocultural characteristics that appear in online communities were also found in Wikipedia Korea. A new, diverse set of external resources is necessary to sustain the collective intelligence. An effort to settle new editors into the wikipedia community and an openness through circulation structure to avoid the exclusiveness of the management group are suggested.

• Journal of Korean Society of Water and Wastewater
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• v.22 no.2
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• pp.205-212
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• 2008

This study aimed to investigate the biofilm formation, bacterial regrowth, and bacterial community structure in the granular-activated carbon (GAC) filter adsorbers (FAs) used in water treatment plants. In 2005 and 2006, raw water, settled water, GAC FA by depth, and filtered water were collected twice a year from water treatment plants (WTPs) B and S. The number of heterotrophic bacteria, including mesophilic and psychrophilic bacteria, in such collected waters was investigated along with the total number of coliforms therein. Heterotrophic bacteria were detected in most samples, mainly at the surface layers of the GAC FAs, and fewer such bacteria were found in the lower and bottom layers. An increase in the bacterial number, however, was observed in the samples from various depths of the GAC FAs in WTPs B and S compared with the surface layers. An increase in the bacterial number was also detected in the filtered water. This may indicate that there is a regrowth of the bacteria in the GAC FA. Considering, however, that heterotrophic bacteria were not found in the filtered water, it can be deduced that most bacteria are removed in the chlorination process. Coliforms were detected at the surface layer of the GAC FAs, but their regrowth was not observed. MicroLog systems were used to identify the bacteria community distribution. Eight genera and 14 species, including Pseudomonas spp., were detected in WTP B, and 8 genera and 9 species, including Aeromonas spp., in WTP S. Further studies are required to elucidate their role in the biofilms in water treatment processes.

• Bulletin of the Korean Chemical Society
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• v.34 no.12
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• pp.3755-3761
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• 2013

This study aims to assess the ecological risk of the hazardous air pollutants (HAPs) emitted in the semiconductor manufacturing processes in Korea by using Quantitative Structure Activity Relationship (QSAR, EPA, US, EPI $Suite^{TM}$ 4.1). Owing to the absence of environmental standards of hazardous air pollutants in the semiconductor manufacturing processes in Korea, 18 HAPs in the semiconductor field included in both the US EPA NESHAPs and the hazardous air pollutant list of Ministry of Environment in Korea were selected. As a results 8 chemicals (44.4%) of the selected 18 HAPs were VOCs. Cyanides (cyanides) and ethylene oxides (epoxy resins), and tetrachloro-ethylene (aliphatic compounds, halides) showed long half-lives. Cyanide HAPs especially had the highest half-life with the estimated value of 356.533 days. Nickel compounds (heavy metal compounds) possessed the highest water solubility followed by acetaldehyde (aldehyde compounds), ethylene oxides, and 1,4-dioxanes. The halides, including tetrachloro-ethylenes, carbon tetra-chlorides, benzene (aromatic compounds), and lead (heavy metals), are estimated to take the longest time for biodegradation. Tetrachloroethylene, with the acute toxicity end point of 3.685-7.033 mg/L, was assessed to be the most highly toxic substance among the 18 HAPs. However, considering the absence of the HAPs in the common category of log $K_{ow}{\geq}4$and $BCF{\geq}500$, which indicates the standard of bioconcentration potentials, potentials of the bioconcentration are considered to be low.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.25 no.2
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• pp.80-84
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• 2015

Mn-Co-Ni oxide system has been used as the NTC thermistors for normal temperature applications. Mn-Co-Ni oxide-based thermistors were sintered at different temperatures for a constant processing time from 900 to $1300^{\circ}C$ for 3 h. The crystal structure, bulk density, microstructure and chemical composition were characterized by XRD, FE-SEM and WD-XRF. The plot of the resistance versus measuring temperature was characterized for the sintered sample at the $1250^{\circ}C$. Moreover, the relationship between log resistivity and reciprocal of absolute temperature of the NTC thermistor was investigated.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.40 no.6
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• pp.24-30
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• 2003

This study focuses on the arithmetical methodology and hardware implementation of low system-complexity A $B^2$＋C operator over GF(2$^{m}$ ) using the irreducible AOP of degree m. The proposed parallel-in parallel-out operator is composed of CS, PP, and MS modules, each can be established using the array structure of AND and XOR gates. The proposed multiplier is composed of (m＋1)$^2$ 2-input AND gates and (m＋1)(m＋2) 2-input XOR gates. And the minimum propagation delay is $T_{A}$ ＋(1＋$\ulcorner$lo $g_2$$^{m}$ $\lrcorner$) $T_{x}$ . Comparison result of the related A $B^2$＋C operators of GF(2$^{m}$ ) are shown by table, It reveals that our operator involve more lower circuit complexity and shorter propagation delay then the others. Moreover, the interconnections of the out operators is very simple, regular, and therefore well-suited for VLSI implementation.

• 한국HCI학회:학술대회논문집
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• 2006.02b
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• pp.761-769
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• 2006

한국사회에서 새로운 미디어 문화로 가장 각광받는 것 중 하나가 '싸이월드(www. cyworld.com)' 이다. 싸이월드는 웹(Web)에서 하루하루의 일기(Log)를 쓰는 개념인 '개인 블로그(Blog)'로써 개인 미니 홈페이지 형태이다. 이는 단순한 트렌드에 그치는 것이 아니라, 2000 년대 초 카페나 커뮤니티를 기반으로 한 '집단(group) 사이버 문화'를 '개인 (individual) 사이버 문화'로 전환시키는 하나의 문화적 수준에서 논의되고 있다. 그런데 블로그 사이버 문화는 자본주의 소비문화와 밀접하게 연결된다. 현대의 사이비 문화는 개인의 능동적 선택과 이용을 전재로 하므로 자율적이고 독창적인 방식으로 미디어 문화를 소비하는 데, 자본주의 경제사회 속에서 개인의 자율성은 표면적인 이미지에 지나지 않는다. 특히 싸이월드와 같은 개인 미디어는 더욱 개인의 자율성에 기반한 문화행위를 실천하지만, 사실 싸이월드틀 움직이는 경제구조 속에서 규제된다. 싸이월드 이용자가 기본 미니홈피 플랫폼에 자신만의 개성을 표현하기 위해서는 '도토리' 라는 싸이월드의 전자화폐를 사용해야 하고, 이를 이용해 미니룸, 미니미, 스킨, 배경음악 등의 아이템을 구매한다. 그러나 싸이월드 이용자들은 개인의 자율성에 의해 소비행위를 창출하는 것이므로 이를 통해 이윤을 획득하는 자본세력에 대해서는 고려하지 않는다. 이것이 바로 자본주의 소비문화에 의해 지배되는 부정적인 '실제의 왜곡' 이다. 개인의 자율성을 강조함으로써 자본가의 이윤획득 구조를 은폐하여 자본본주의 소비를 재생산하고 강화하는 것이다. 따라서 우리는 개인 문화를 강조하는 현대 미디어 문화구조를 자본주의 권력의 장(場)으로 이해해야 한다. 그리고 미디어 문화의 생산과 소비를 통해 자본주의 소비 문화가 재생산되고 강화되는 현상을 비판함으로써 온라인 블로그의 커뮤니케이션 특성이 생산자(producer)로서의 기능보다 소비자(consumer) 로서의 기능이 강조되고 있음을 이해해야 할 것이다.

• Journal of the Korean Geotechnical Society
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• v.20 no.8
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• pp.15-27
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• 2004

Sliding aspects of rock slope, where large-scaled tension cracks are induced during preliminary excavation, have been analyzed. Structure of rock mass is investigated by performing the electrical resistivity survey and the orientations and positions of discontinuities are measured from DOM-drilled core log. Geological evidence far primary failure movement has been detected and clay minerals which possess swelling properties are identified through XRD analysis. Slope stability is examined by considering the orientations of discontinuities and their trace distributions on the cut-face and neighboring natural slope surface. Both orientations and positions of failure-invoking discontinuity planes, traces of which are exposed within the anticipated sliding region, are concerned fur analyzing the preferred sliding directions. Regional sliding vectors are assessed based on the relative positions of potential sliding planes in the boreholes and the general trend of anticipated failure movement of rock slope is also investigated.

• Journal of the Korean Geotechnical Society
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• v.29 no.3
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• pp.61-70
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• 2013

Evaluation of permeability and coefficient of consolidation of clayey sand is critical in analyzing ground stability or environmental problems such as prediction of pollutant transport in groundwater. In this study, permeability tests using a flexible wall permeameter are performed to derive the coefficient of consolidation and permeability of reconstituted soil samples with various mixing ratios of kaolin clays and two different types of sands, which are Jumunjin and Ottawa sands. The test results indicate that the coefficient of consolidation and permeability plots linearly against clay contents in semi-log scale graphs for low clay mixing ratios ranging between 10 to 30%. It is also demonstrated that coefficient of consolidation and permeability of sand and clay mixture are dependent on the soil structure. Contrary to previous findings, the permeability is shown to be independent of the void ratio at low mixing ratios, which can be classified as non-floating fabric. The permeability decreases with the void ratio for floating fabric.