• Journal of the korean academy of Pediatric Dentistry
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• v.45 no.3
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• pp.314-323
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• 2018

The aim of this study was to evaluate the shear bond strength of three luting cements and to identify the effect of thermocycling. Zirconia discs were made similar to the inner surface of a preformed pediatric zirconia crown ($NuSmile^{(R)}$ ZR crown: ZRCr). The similarity between the zirconia discs and the inner surface of a ZRCr was confirmed by scanning electron microscope. Three luting cements were $Ketac^{TM}$ Cem Permanent Glass Ionomer Luting Cement (KGI), $RelyX^{TM}$ Luting Plus Cement (RLP), $RelyX^{TM}$ Unicem Self-Adhesive Universal Resin Cement (RUR). Three luting cements were bonded according to the manufacturer's instructions for 60 zirconia discs and 60 dentin of primary teeth. Total of 120 specimens were divided into two subgroups: One was not aged, and the other was tested with 5500 thermocycling. Shear bond strength was measured using a universal testing machine, and the fracture patterns were observed with SEM. On the zirconia discs and the dentin of primary teeth, shear bond strength of RUR was higher than that of KGI and RLP, and there were statistically significant differences by cement type. The shear bond strength differences for RUR were not statistically significant depending on thermocycling.

• The KIPS Transactions:PartD
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• v.12D no.2 s.98
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• pp.233-246
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• 2005

To enhance the user response time of content-based retrieval service for multimedia information, several multi-dimensional index schemes have been proposed. M-tree, a well-known multidimensional index scheme is of metric space access method, and is based on the distance between objects in the metric space. However, since the overlap between index spaces of nodes might enlarge the number of nodes of M-tree accessed for query processing, the user response time for content-based multimedia information retrieval grows longer. In this paper, we propose a node split algorithm which is able to reduce the sire of overlap between index spaces of nodes in M-tree. In the proposed scheme, we choose a virtual center point as the routing object and entry redistribution as the postprocessing after node split in order to reduce the radius of index space of a node, and finally in order to reduce the overlap between the index spaces of routing nodes. From the experimental results, we can see the proposed split algorithm reduce the overlap between index space of nodes and finally enhance the user response time for similarity-based query processing.

• The Transactions of the Korea Information Processing Society
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• v.4 no.6
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• pp.1418-1432
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• 1997

Most general content_based image retrieval techniques use color and texture as retrieval indices. In color techniques, color histogram and color pair based color retrieval techniques suffer from a lack of spatial information and text. And This paper describes the design and implementation of content_based image retrieval system using color space and keywords. The preprocessor for image retrieval has used the coordinate system of the existing HSI(Hue, Saturation, Intensity) and preformed to split One image into chromatic region and achromatic region respectively, It is necessary to normalize the size of image for 200*N or N*200 and to convert true colors into 256 color. Two color histograms for background and object are used in order to decide on color selection in the color space. Spatial information is obtained using a maximum entropy discretization. It is possible to choose the class, color, shape, location and size of image by using keyword. An input color is limited by 15 kinds keyword of chromatic and achromatic colors of the Korea Industrial Standards. Image retrieval method is used as the key of retrieval properties in the similarity. The weight values of color space ${\alpha}(%)and\;keyword\;{\beta}(%)$ can be chosen by the user in inputting the query words, controlling the values according to the properties of image_contents. The result of retrieval in the test using extracted feature such as color space and keyword to the query image are lower that those of weight value. In the case of weight value, the average of te measuring parameters shows approximate Precision(0.858), Recall(0.936), RT(1), MT(0). The above results have proved higher retrieval effects than the content_based image retrieval by using color space of keywords.

• The Journal of Society for e-Business Studies
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• v.15 no.3
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• pp.131-145
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• 2010

Until now, popular paradigms to provide e-catalog documents that are adapted to users' needs are keyword search or collaborative filtering based recommendation. Since users' queries are too short to represent what users want, it is hard to provide the users with e-catalog documents that are adapted to their needs(i.e., queries and preferences). Although various techniques have beenproposed to overcome this problem, they are based on index term matching. A conventional Bayesian belief network-based approach represents the users' needs and e-catalog documents with their corresponding concepts. However, since the concepts are the index terms that are extracted from the e-catalog documents, it is hard to represent relationships between concepts. In our work, we extend the conventional Bayesian belief network based approach to represent users' needs and e-catalog documents with a concept network which is derived from the Web directory. By exploiting the concept network, it is possible to search conceptually relevant e-catalog documents although they do not contain the index terms of queries. Furthermore, by computing the conceptual similarity between users, we can exploit a semantic collaborative filtering technique for recommending e-catalog documents.

• The Korean Journal of Cytopathology
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• v.1 no.2
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• pp.152-157
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• 1990

A 70-year-old female who was diagnosed as myxoid chondrosarcoma by fine needle aspiration of a pleural mass is described. She presented with left chest discomfort of 4 months' duration and aggravating dyspnea and chest pain for 2 months. Chest X-ray and CT scan revealed a large lobulated low density mass invading chest wall at the left pleural cavity and massive pleural fluid. Fine needle aspiration was done under the impression of mesothelioma or metastatic cancer. The aspirates from the mass were very cellular and composed of isolated or clustered forms of large plump cells. Abundant cytoplasm was blulsh opaque and the margin was rounded in the isolated cells, whereas clustered cells show ill-defined ceil borders and aggregating tendency. The nuclei were eccentric, round to ovoid, and had fine chromatin pattern and multiple small nucleoli. Cellular pleomorphism or mitotic figure was not definite. These findings were consistent with cytologic features of chondrosarcoma. Final diagnosis was confirmed as myxoid chondrosarcoma by mediastinoscopic biopsy and the tumor showed strong positivity for S-100 protein.

• The KIPS Transactions:PartD
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• v.13D no.7 s.110
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• pp.857-866
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• 2006

Performance of an image retrieval system is usually very low because of the semantic gap between the low level feature and the high level concept in a query image. Semantically relevant images may exhibit very different visual characteristics, and may be scattered in several clusters. In this paper, we propose a content based image rertrieval approach which combines region based image retrieval and a new relevance feedback method using adaptive clustering together. Our main goal is finding semantically related clusters to narrow down the semantic gap. Our method consists of region based clustering processes and cluster-merging process. All segmented regions of relevant images are organized into semantically related hierarchical clusters, and clusters are merged by finding the number of the latent clusters. This method, in the cluster-merging process, applies r: using v principal components instead of classical Hotelling's $T_v^2$ [1] to find the unknown number of clusters and resolve the singularity problem in high dimensions and demonstrate that there is little difference between the performance of $T^2$ and that of $T_v^2$. Experiments have demonstrated that the proposed approach is effective in improving the performance of an image retrieval system.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2003.05a
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• pp.414-417
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• 2003

유역의 경사가 비교적 급하고, 소규모 축산농가의 미처리된 축산폐수 및 농경지 배수, 산재된 마을하수 등 비점오염원의 유출이 강우시 집중적으로 이루어지는 중산간 농업용 저수지의 수질개선을 위한 공법으로 부영양화된 충남 아산 마산저수지의 유입부에 조성한 저류지를 이용한 수질개선효과 및 물질분해자로서 미생물학적 특성을 2000년부터 2002년까지 3년간 연구함으로서 향후 유사한 농업용저수지의 수질개선 방안으로 실용화 가능성을 모색하고자 하였다. 그 결과 수질정화효과는 총질소와 총인 등 영양염류의 정화효과가 비교적 우수하게 나타났으며, 유기오염물질로서 BOD, COD, SS 등은 평균 수질정화효과는 (-)의 값을 보여주었으나, 강우기에는 정화효율이 높게 나타났다 또한, 저류지의 물질 침전기능 외 오염물질의 활발한 분해작용을 살펴보고자 세균 분포 특성을 조사한 결과 유입수와 저류지, 저수지 각각의 수체에서 조사된 총세균수 및 총세균수에 대한 진정세균수의 비율이 유입수<저류지<유출수의 순으로 나타나 저류지의 유기물질 분해 활성이 높음을 보여주고 있다. 따라서 저수지 유입부에 조성한 저류지의 수질개선효과는 강우시 입자성 유기물질의 효과적 제거 뿐만아니라 영양염류의 제거효과, 특히 질소의 제거효과가 높은 정화기구로서 설치비용이 적고, 유지관리가 간단한 특성을 살려 유사한 중규모 농업용저수지의 수질개선 기법으로 널리 활용할 가치가 있음으로 사료된다.

• The KIPS Transactions:PartB
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• v.18B no.2
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• pp.87-92
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• 2011

In Korean documents, there are diverse spellings of transliterated foreign loanwords. This fact diminishes the performance of information retrieval systems in that a foreign word can be recognized differently, which is to say, as two or several different words. Thus, information retrieval systems require preprocessing to correct nonstandard loanword spellings prior to searching and recognizing corresponding equivalent words. This paper proposes a method that improves precision and processing efficiency using the Korean alphabet's viable prefix, which prunes a virtual tree from which candidate loanwords are created.

• Journal of Korea Multimedia Society
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• v.7 no.4
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• pp.474-483
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• 2004

In this paper, we present a new Practical implementation of a person verification system using the profile of 3-dimensional(3D) face images based on weighted Hausdorff distance(WHD) used depth information. The approach works on finding the nose tip have protrusion shape on the face using iterative selection method to use a fiducial feint and extract the profile image from vertical 3D data for the nose tip. Hausdorff distance(HD) is one of usually used measures for object matching. This works analyze the conventional HD and WHD, which the weighted factor is depth information. The Ll measure for comparing two feature vectors were used, because it is simple and robust. In the experimental results, the WHD method achieves recognition rate of 94.3% when the ranked threshold is 5.

• The KIPS Transactions:PartD
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• v.11D no.5
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• pp.1133-1142
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• 2004

This paper proposes a method to classify and retrieve components in repository using the idea of domain orientation for the successful reuse of components. A design pattern was applied to existing systems and a component classification method is suggested here to compare the structural similarity between each component in relevant domain and criterion patterns. Classifying reusable components by their functionality and then depicting their structures with a diagram can increase component reusability and portability between platforms. Efficiency of component reuse can be raised because the most appropriate component to query and similar candidate components are provided in priority by use of-SARM algorithm.