• Korean Journal of Construction Engineering and Management
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• v.13 no.3
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• pp.14-24
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• 2012

Recently, a delivery system has been rapidly changed in the global construction market. Also, construction projects are becoming bigger and more technology-intensive. A lot of projects have been delivered by Design-Build(DB) System; from the standpoint of cost, approximately 40% of delivered constructions by a Public Procurement Service were DB in 2009. Nevertheless, the achievement has not surpassed our expectations on management of the project cost. On the characteristic of DB, the reasons why that happens are that projects contract have been signed after the Design Development Stage; the insufficient review about new technology and up-to-date construction methods; a lack of discussion in process of design. Those reasons cause a risk of increasing Cost of the projects. In order to solve these problems, it is desirable to find Cost-increasing factors in promoting the projects and select on the order of priority for Risk-Factor with careful management. Therefore, this study analyzed the weight of each phase of the project on the authority of properties of DB project, and identified Risk-factors which is increasing the cost on the aspect of project management. Based on this analysis, the impact assessment of Risk-factor is evaluated through the Failure Mode and Effect Analysis(FMEA).

• Investigative Magnetic Resonance Imaging
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• v.5 no.1
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• pp.49-56
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• 2001

Purpose : To evaluate value of superparamagnetic iron oxide (SPIO) as a negative oral contrast agent in MR cholangiopancreatography (MRCP). Materials and methods : Forty-eight patients with suspected biliary tract or pancreatic diseases and six healthy volunteers were enrolled in this study. All MR images were obtained using a 1.5 T MR unit. MR-CP using fat-suppressed half-Fourier acquisition single-shot turbo spin echo (HASTE) and turbo spin echo (TSE) techniques were performed and reconstructed with maximal intensity projection (MIP). To determine the most optimal concentration of SPIO to obliterate the high signal intensity of water, a phantom experiment was conducted with various concentrations of SPIO-water mixture. Two radiologists evaluated pre- and postcontrast MRCPS. The contrast enhancement was assessed on the basis of loss of signal intensity in the stomach and duodenum. Results : In the phantom experiment, a significant increase of percentage of signal intensity loss (PSIL) occurred in concentration of 22.4 ugFe/ml (Feridex1 ml diluted with water 500 ml). Postcontrast MRCP showed an improved image quality compared with precontrast images. The rate of improvement in the diagnosis of diseases of the common bile duct and pancreatic duct was 25% (12/48). Conclusion : In patients with suspected biliary tract and pancreatic diseases, the SPIO is useful as a negative oral contrast agent for MRCP and provides an improvement of image quality.

• Journal of Engineering Education Research
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• v.13 no.1
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• pp.23-37
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• 2010

The purpose of this study is to explore applicability of teaching-learning methods for creative problem solving which was designed to improve students' creative thinking and problem solving competencies. Methodology is literature review and focus group interview. The students who attended the elective course 'creative women and science' was participated during 15 weeks. Through this teaching-learning methods, students were fully aware of learning methods for creative problem solving, sought for problems, clarified problems, found solutions through discussions, and continuously examined ideas by receiving feedbacks. They could deduce creative new solutions to solve encountered problems regarding team dynamics and apply it in real situation. As the results of applying teaching-learning methods for creative problem solving to a course in University, it had the advantages of enhancing students' competencies in analyzing problems and applying derived solutions in actual field.

• Journal of the Korean Society of Clothing and Textiles
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• v.29 no.12 s.148
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• pp.1554-1561
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• 2005

This study aims to analyze modern hairstyle and fashion in the collections in the late 1990s, based on the concepts and characteristics of Minimalism, a buzzword of the art field in the 1960s. This study used qualitative research method, in other words, presenting an analysis framework by studying domestic and foreign books and dissertations on Minimalism and then applying the Internet or visual image to the analysis framework. The result indicates that Minimalism design in modem hairstyle and fashion has four characteristics: simplicity, unity, repetition and spatiality.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.23 no.4
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• pp.393-399
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• 2005

Since vegetations are near the wavelength range in 700nm and have absorbent as well as reflective wavelength ranges, there is a much difference in terms of its reflection rate. There are currently many researches on vegetation index being conducted in order to apply the remote-sensing technology to vegetations rising their characteristics of absorbent and reflective wavelength ranges. Normalized Difference Vegetation Index (NDVI) and Perpendicular Vegetation Index (PVI) have been most commonly used. It is usually the evaporation, carbon-dioxide consumption, and chlorophyll density that represent the activity of vegetation, but chlorophyll density is the most commonly used among them. Since the red wavelength range used to obtain the NDVI and PVI has a strong extinction of chlorophyll, it is also useful to test chlorophyll density. The NDVI, in particular, is used to identify the vegetation conditions summarily, and thus, is suitable for initiative researches. Nevertheless, since these vegetation index produce mixed information of the Vegetation vigor and vegetation cover, it is essential to monitor a wavelength range that is independent from redundancy of the Vegetation vigor and vegetation cover. Although many vegetation indices have evaluated both the vegetation vigor and Vegetation cover simultaneously, this research intends to emphasize the utility of separable evaluations of the Vegetation vigor and Vegetation Cover rate through an experiment with grasses. As a result of evaluating vegetation index using spectral reflectance, a separable evaluation of the vegetation vigor and cover has been found more useful.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.32 no.5
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• pp.443-450
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• 2014

To fulfill the recent increasement in the public and private demands for various spatial data, the central and local governments started to produce those data. The low-level land cover map has been produced since 2000, yet the production of high-level land covered map has started later in 2010, and recently, a few regions was completed recently. Although many studies have been carried to improve the quality of land that covered in the map, most of them have been focused on the low-level and mid-level classifications. For that reason, the study for high-level classification is still insufficient. Therefore, in this study, we suggested the automatic extraction of land readjustment for paddy land that updated in the mid-level land mapping. At the study, the RapidEye satellite images, which consider efficient to apply in the agricultural field, were used, and the high pass filtering emphasized the outline of paddy field. Also, the binary images of the paddy outlines were generated from the Otsu thresholding. The boundary information of paddy field was extracted from the image-to-map registrations and masking of paddy land cover. Lastly, the snapped edges were linked, as well as the linear features of paddy outlines were extracted by the regional Hough line extraction. The start and end points that were close to each other were linked to complete the paddy field outlines. In fact, the boundary of readjusted paddy fields was able to be extracted efficiently. We could conclude in that this study contributed to the automatic production of a high-level land cover map for paddy fields.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.13 no.1
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• pp.177-185
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• 2009

Cluster analysis or clustering is a kind of unsupervised learning method in which a set of data points is divided into a given number of homogeneous groups. Fuzzy clustering method, one of the most popular clustering method, allows a point to belong to all the clusters with different degrees, so produces more intuitive and natural clusters than hard clustering method does. Even more some of fuzzy clustering variants have noise-immunity. In this paper, we improved the Possibilistic Fuzzy C-Means (PFCM), which generates a membership matrix as well as a typicality matrix, using Gath-Geva (GG) method. The proposed method has a focus on the boundaries of clusters, which is different from most of the other methods having a focus on the centers of clusters. The generated membership values are suitable for the classification-type applications. As the typicality values generated from the algorithm have a similar distribution with the values of density function of Gaussian distribution, it is useful for Gaussian-type density estimation. Even more GG method can handle the clusters having different numbers of data points, which the other well-known method by Gustafson and Kessel can not. All of these points are obvious in the experimental results.

• Investigative Magnetic Resonance Imaging
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• v.1 no.1
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• pp.130-134
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• 1997

Purpose: To analyze contrast-enhancement pattern of stomach cancer on dynamic MRI and to verify the efficacy of intravenous contrast agent in the evaluation of stomach cancer. Materials and Methods: Twelve patients with proven stomach cancer underwent dynamic MRI. By using l.OT scanner, we obtained precontrast FLASH images, and 30, 60, 90 second delay FLASH images after intravenous contrast injection. All patients ingested one liter of water and had intramuscular injection of Buscopan just before MR study. For quantitative analysis we measured signal to noise ratio (SiN) of stomach cancer on each image, and signal difference to noise ratio (SD/N) between cancer and intraluminal fluid, cancer and the pancreas. For qualitative analysis two radiologists evaluated lesion conspicuity on each image by grading system(grade 0, 1, 2, 3: poor, fair, good, excellent). Results: SiN of stomach cancer increased gradually by time(precontrast, 30, 60, 90 second delay: 38.7, 42.5, 57.4, 65.7). SD/N between cancer and intraluminal fluid significantly increased after contrast enhancement(l.24, 25.01, 39.30, 45.89). SD/Ns between cancer and the pancreas were 10.5, 9.33, 9.99, 10.66, respectively. In qualitative analysis, precontrast images were better than postcontrast images for delineation of stomach cancer. Postcontrast images showed clear endo-Iuminal side of stomach cancer, but outer margin of stomach cancer was more distinct on precontrast images. Conclusion: Precontrast MR images are better than postcontrast MR images in the depiction of stomach cancer. Intravenous contrast agent is not imperative in the evaluation of stomach cancer.

• The Journal of the Korea Contents Association
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• v.9 no.8
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• pp.129-137
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• 2009

While the broadband network and multimedia technologies have been developing, the commercial market of digital contents also has been widely spreading with recently starting IPTV. As the IPTV services are getting to be generalized and popularized, the contents protection and authentication system tends to draw more attentions. So we need a system that can protect contents and allow only authenticated person to use right service by controling user authority and using content encryption. Until now, the conventional protection and authentication system is taking advantages of merits both in CAS and DRM. But the weak point of this system are in high costs, complexity and using HW. For resolving these problems, in this paper, we proposed IPTV contents protection and authentication system using OTP. When we transmit the content encrypted by OTP key using contents delivery technology, we operate XOR with contents using another settop-box's OTP key which was transmitted from distribution server. And contents are reconstructed and transmitted to the settop-box, In the end, downloaded content are encrypted by OTP key and are superior in content protection when contents redistribution. Since OTP use double-authentication elements in encryption process, this method is excellent in content protection. And it is very effective in cost aspect because it could be implemented by SW program. Another benefit is that we can shorten the development time period. In this paper, we propose and find its possibility as a new content protection and authentication method suitable for IPTV services.

• Journal of the Korean Society for information Management
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• v.19 no.3
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• pp.123-143
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• 2002

Developing good methods for image description and indexing is fundamental for successful image retrieval, regardless of the content of images. Researchers and practitioners in the field of image indexing have developed a variety of image indexing systems and methods with the consideration of information types delivered by images. Such efforts in developing image indexing systems and methods include Panofsky's levels of image indexing and indexing systems adopting different approaches such as thesauri-based approach, classification approach. description element-based approach, and categorization approach. This study investigated users' perception of the objectiveness of image indexing, especially the iconographical analysis of image information advocated by Panofsky. One of the best examples of subjectiveness and conditional-dependence of image information is emotion. As a result, this study dealt with visual emotional information. Experiments were conducted in two phases : one was to measure the degree of agreement or disagreement about the emotional content of pictures among forty-eight participants and the other was to examine the inter-rater consistency defined as the degree of users' agreement on indexing. The results showed that the experiment participants made fairly subjective interpretation when they were viewing pictures. It was also found that the subjective interpretation made by the participants resulted from the individual differences in terms of their educational or cultural background. The study results emphasize the importance of developing new ways of indexing and/or searching for images, which can alleviate the limitations of access to images due to the subjective interpretation made by different users.