• Journal of Korean Society of Environmental Engineers
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• v.31 no.2
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• pp.119-124
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• 2009

The aim of this study was to investigate the influence of ionic strength and iron impregnation on the attachment of Enterococcus faecalis to granular activated carbon (GAC). Column experiments were performed to examine bacterial adhesion to coconutbased GAC (c-GAC), iron-impregnated c-GAC (fc-GAC), acid-washed c-GAC (a-GAC) and iron-impregnated a-GAC (fa-GAC) under two different solution (NaCl 1, 10 mM) conditions. Results showed that bacterial mass recovery in c-GAC decreased from 77.3 to 61.6% while in a-GAC it decreased from 71.6 to 32.3% with increasing ionic strength from 1 to 10 mM. This indicates that bacterial attachment to GAC can be enhanced with increasing ionic strength. Results also showed that the mass recoveries in fc-GAC were 62.6% (1 mM) and 53.3% (10 mM) while they were 50.8% (1 mM) and 16.9%(10 mM) in fa-GAC, which were lower than those in c-GAC and a-GAC. This demonstrates that bacterial adhesion to GAC can be enhanced through iron impregnation. This study provides information regarding the effects of ionic strength and iron impregnation on bacterial attachment to GAC. Furthermore, this study will advance our knowledge of bacterial removal in surface-modified granular media.

• Restorative Dentistry and Endodontics
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• v.30 no.5
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• pp.393-401
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• 2005

The purpose of this study was to compare the canal configuration after shaping by ProTaper rotary files and ProTaper hand files in resin simulated canals. Forty resin simulated canals with a curvature of J-shape and S-shape were divided into four groups by 10 blocks each Simulated root canals in resin block were prepared by ProTaper rotary files and ProTaper hand files using a crown-down pressureless technique All simulated canals were prepared up to size $\#25$ file at end-point of preparation. Pre- and post-instrumentation images were recorded with color scanner. Assessment of canal shape was completed with an image analysis program. Measurements were made at 0, 1, 2, 3, 4, 5, 6 and 7 mm from the apex. At each level, outer canal width, inner canal width, total canal width, and amount of transportation from original axis were recorded. Instrumentation time was recorded. The data were analyzed statistically using independent t-test. The result was that ProTaper hand files cause significantly less canal transportation from original axis of canal body and maintain original canal configuration better than ProTaper rotary files, however ProTaper hand files take more shaping time.

• Spatial Information Research
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• v.23 no.5
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• pp.1-7
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• 2015

Twitter has the fast propagation and diffusion of information compare to other SNS. Therefore, many researches about detecting real-time event using twitter are progressing. Twitter real-time event detecting system assumes every twitter user as a sensor and analyzes their written tweet in order to detect the event. Researches that are related to this twitter have already obtained good results but confronted the limits because of some problems. Especially, many existing researches are using the method that can trace an event location by using GPS coordinate. However, it can be suggested a definite limitation through the present user's skeptical responses about making personal location information public. Therefore, this paper suggests the method that traces the location information in tweet contents text without using the provided location information from twitter. Associated words were grouped by using the keyword that extracted in tweet contents text. The place that the events have occurred and whether the events have surely occurred are detected by this experiment using this algorithm. Furthermore, this experiment demonstrated the necessity of the suggested methods by showing faster detection compare to the other existing media.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.8 no.3
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• pp.11-19
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• 2009

At present, an intelligent transport system (ITS) is being actively introduced as an alternative plan to solve various transport problems, and a traffic information provision service, a field of ITS, is being provided to users through diverse media. However, the evaluation of how useful the traffic information provided to the road users is limited to a simple questionnaire, and the systematic evaluation about what factors affect the usefulness of traffic information has not been realized. Therefore, it is impossible to calculate user convenience occurring due to traffic information, This paper aimed to develop an index to evaluate user satisfaction levels with traffic information and develop a user satisfaction level model. A result of establishing a user satisfaction level model by executing a questionnaire survey for the analysis object of variable message sign (VMS), a representative information provision medium, showed that 'desire satisfaction', 'trust', 'understanding', and 'efficiency' have an effect. Of them, the 'understanding' showed the highest level, so it was seen that, in case of VMS, how easily the character, figure, expression, etc. provided in the information was understood by users has the biggest effect on the satisfaction level of the information. The next levels of effects on the satisfaction was in the order of 'user trust', 'efficiency', and 'desire satisfaction'.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.16 no.2
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• pp.27-40
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• 2016

This paper aims to analyze the business types of 237 IoT based smart home companies in the world (launched during 1999~2014) which got global investment last few years. For this, the previous literatures trying to analze technology and service types of smart home are searched and the typology of the platform is discussed. Based on it, this research conceptualizes an analysis framework that includes three areas of smart home like home automation, home security, and energy efficiency with the three platform types like product, software, and service. This study concludes that the development of business type for IoT based smart home ecosystem is from the product to software and it can be a platform or not. In current status, there are a few platforms of product and software, but in the device management (16%) and thermostat (11%), companies are persuing more platform like. It is difficult to find the service platform in overall areas, for application based service has a few attractions in the investment market due to the lack of cloud infrastructure and data analytics. The following three are the implication to domestic market: 1) More active offering of API and SDK, 2) more active introduction of wireless Intenet network protocols, and 3) more active interoperability efforts and alliance activities are needed.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.18 no.4
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• pp.43-48
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• 2018

This study was conducted to reproduce digital colour based on the lightness of the background and size of the colour stimulus so that colour can be similarly perceived under different conditions. With the evolution of display technologies, display devices of various sizes can now reproduce more accurate colour and enhanced images, thus affecting the overall quality of display images. This study reproduced digital colour by considering the visual characteristics of the digital media environment. To accomplish this, we developed a colour appearance model which distinguishes the properties of foveal and peripheral vision. The proposed model is based on existing research on the lightness of the background and size of the colour stimulus. Based on experimental results, an analysis of variance was performed in order to develop the colour appearance model. The algorithm and modelling were verified based on the proposed model. In addition, to apply this model to display technologies, a practical colour control system and a method for handling complex input images were developed. Through this research, colour conversion errors which might occur when the input image is converted to fit a specific display size are resolved from the perspective of the human visual system. As a result, more accurate colour can be displayed and enhanced images can be reproduced.

• Korean Journal of Environment and Ecology
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• v.18 no.2
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• pp.249-262
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• 2004

This study was conducted to suggest alternatives for the effective use of national park visitor centers, by evaluating their functionality. Visitor centers in Naejangsan National Park and Pukhansan National Park, which are deliberately composed and managed, were investigated for this purpose. First, I clarified the concept, function and type of a visitor center through literature review, and then, analyzed visitors' post-visiting evaluation based on McManus's Communication Theory. The results of the analysis shows that visitors have not enough time to understand the contents of visitor centers, and facilities and guide sign system to support visitors are insufficient, which seem to disturb the proper communication between visitors and exhibits. Visitors' short visiting time caused by their little interest in exhibits and their low degree of understanding show the difficulties in the communication between visitors and exhibits. The following alternatives are suggested to improve these problems: first, the improvement of the guide sign system; second, the provision of exhibition rooms specialized for different visitor groups; third, the display of exhibits connected with visitors' experiences; Forth, the utilization of various media proper for each subject.

• Korean journal of communication and information
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• v.46
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• pp.245-279
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• 2009

UCC, an abbreviation for User Created Contents, is not only a symbol of desire but also a product of creativity that a producer contains his or her subjective disposition. More and more UCC tend to have significantly increased in Web 2.0 environment. However, the research on the contents as a creative product has rarely been processed. It may be fairly said that this results in the indifference of researchers in the special field like the political contents since UCC is usually produced by amateurs. Producers' various desire is unlikely revealed, which leads to the flow of users into open media such as the Internet. It could also be available to represent the property, of plural visual language signs in a field. Moreover, UCC has the attribute of re-mediation in effective communication, so the differences between the semiotic properties in the Internet contents could be a significant material for researches. This could contribute to establish a theoretical system for the visual communication. Therefore, this study aims to analyse the signification of the political video UCC, . To develop this analysis, I apply Greimas' Generative Trajectory of Signification Theory to the text, or the UCC. He classifies it as three structures: deep structure, superficial structure, and discourse structure. As a result, the text shows meaningful contents delivering core political messages. In addition, this approach could exam that 'Obama Syndrome' in American recent presidential campaigns is caused by web 2.0 based on Internet campaigns including video UCC.

• Korean Journal of Child Studies
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• v.1
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• pp.1-14
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• 1980

The purpose of this study was to survey the degree of awareness and practice concerning prenatal care among Korean women. In this study, 626women in Seoul, Sungnam City, and Yangju Kun were randomly selected to be given a questionare that was formulated by the researcher. The statistical analysis of the data was obtained by percentage scores and $X^2$ scores on each item by age, educational background, and regional areas. The general out come of the study were as follows. A. The Practice of Prenatal Care 1. Physical Activities: Concerning the hard work, about a half of the women took care of it by themselves, and the others treated it with help. Also it was found that they tried to reduce the amount of travel as much as possible during pregnancy. 2. Dietary Intake: It was revealed that no significant change were observed before and during pregnancy. 3. Drugs: It was revealed that they tried to avoid drugs as much as possible during pregnancy. 4. Emotion: About a half of the women said that the family atmosphere did not change before and during pregnancy. The others said it had improved after pregnancy. In their spare time, most pregnant women rested in bed, read books, and listened to music. 5. Husband's Support: Most of the women expressed that they needed thief-husband's support absolutely, especially with hard work. They moderated the sexual activities when they found that they were pregnant. B. Degree of awareness for Prenatal Care 1. Perception of Prenatal Care: Most women heard about prenatal care at least one time through family, friend, or mass-media. 2. Necessity of Prenatal Care: Most women recognized the necessity of prenatal care, and they thought that the relaxation of body and mind was important during pregnancy. 3. Influence of Prenatal Care: It was revealed that most women recognized the positive influence of prenatal care to the neonate. 4. Practice of Prenatal Care: It shown that the most of pregnant women took serious interest in prenatal care and they tended to be careful during pregnancy. Generally speaking, the difference in educational background seemed to affect most to the pregnant women's awareness and practice of prenatal care: the higher the educational achievement, the more cautious about the prenatal care. The difference in region seemed to affect considerably in most aspects of practice: women in urban areas preceeded the rural women in prenatal care. The age difference seemed to affect least in their prenatal care except the younger generation took more care in avoiding the use of drugs.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.46 no.6
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• pp.43-57
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• 2009

Integrating 3D data acquired in multiple views is one of the most important techniques in 3D modeling. However, the existing integration methods are sensitive to registration errors and surface scanning noise. In this paper, we propose a integration algorithm using the local surface topology. We first find all boundary vertex pairs satisfying a prescribed geometric condition in the areas between neighboring surfaces, and then separates areas to several regions by using boundary vertex pairs. We next compute best fitting planes suitable to each regions through PCA(Principal Component Analysis). They are used to produce triangles that be inserted into empty areas between neighboring surfaces. Since each regions between neighboring surfaces can be integrated by using local surface topology, a proposed method is robust to registration errors and surface scanning noise. We also propose a method integrating of textures by using parameterization technique. We first transforms integrated surface into initial viewpoints of each surfaces. We then project each textures to transformed integrated surface. They will be then assigned into parameter domain for integrated surface and be integrated according to the seaming lines for surfaces. Experimental results show that the proposed method is efficient to face modeling.