• Proceedings of the Korean Information Science Society Conference
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• 2003.10a
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• pp.502-504
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• 2003

사전식 압축 방식이라 불리는 LZ-압축은 빠르고도 좋은 압축률을 가지고 있기 때문에 널리 이용되고 있다. 그래서 LZ-압축 방식을 이미지 압축에 적용하는 시도가 이루어지고 있으나 아직 명확하게 정의가 이루어지지 않거나, 정확한 실험 결과가 제시되지 않은 경우가 많다. 이 논문에서는 기존의 정사각형을 이용한 압축 과정 중 다소 모호했던 파싱 과정을 명확히 하며, 매칭에 사용된 정사각형들이 겹쳐지는 비율에 관한 확률적 분석 및 실험 결과를 제시한다. 또한 Test Image Set에 관한 정확한 압축률을 제시한다. 특히 이 논문은 정사각형들이 겹쳐지는 비율에 관한 최초의 확률적 분석을 제시하고 있다.

• Journal of KIISE
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• v.42 no.1
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• pp.33-43
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• 2015

Recently, patent images are growing importance and thus patent image retrieval is a growing area of research. However, most existing patent image retrieval systems use edges extracted in the images, whose performance is affected by the quality of edge detection in the image pre-processing step. To overcome this disadvantage, we propose a SURF-based patent image retrieval method which uses the morphological characteristics of the images. The proposed method detects SURF interest points with directions and computes regional histograms. We apply the proposed method to a patent image database with 2000 binary images and we show the proposed retrieval system achieves excellent results, even when the images have some loss or degradation.

• Proceedings of the Korea Information Processing Society Conference
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• 2011.11a
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• pp.429-430
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• 2011

Roughness set theory is a popular topic to use in color-image segmentation. A new popular color image segmentation algorithm is proposed by scientists with the point using traditional histogram and Histon construct roughness set histogram. But, there is still a problem about that is the correlativity of color vector in roughness set histogram, which take an inactive effect in the process of color-image segmentation. Therefore, this paper represents further research based on this and proposed an improved method proved through lot of experiments. The experimental result reduces the correlativity of color vector in roughness set histogram and calculation time remarkably.

• Proceedings of the Korean Information Science Society Conference
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• 2012.06c
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• pp.245-247
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• 2012

We know that JPEG image format is one of the most popular image formats in the digital area and distribution of digital photographic drawing it is interested frequently in certain types of forensic investigation. In most case, corrupted images are shown gaudiness with the boundary of the corrupted parts. In the paper, we propose a technique to carve correct JPEG images using transformation method and the approach can be used for JPEG image file carving tool development.

• Journal of KIISE:Computing Practices and Letters
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• v.10 no.3
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• pp.243-250
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• 2004

We describe a practical implementation of DVR (Digital Video Recording) system. And we propose a new image compression algorithm, that input video signal is divided into two parts, a moving target and a non-moving background part to achieve efficient compression of image sequences. This algorithm reorganizes a target area and a back-ground area by use of Macro Block(MB) unit on encoding scheme. The proposed algorithm allows high quality image reconstruction at low bit rates.

• Journal of Computing Science and Engineering
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• v.4 no.4
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• pp.368-387
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• 2010

We propose a novel method for the registration of 3D CT scans to 2D endoscopic images during the image-guided medialization laryngoplasty. This study aims to allow the surgeon to find the precise configuration of the implant and place it into the desired location by employing accurate registration methods of the 3D CT data to intra-operative patient and interactive visualization tools for the registered images. In this study, the proposed registration methods enable the surgeon to compare the outcome of the procedure to the pre-planned shape by matching the vocal folds in the CT rendered images to the endoscopic images. The 3D image fusion provides an interactive and intuitive guidance for surgeon by visualizing a combined and correlated relationship of the multiple imaging modalities. The 3D Magic Lens helps to effectively visualize laryngeal anatomical structures by applying different transparencies and transfer functions to the region of interest. The preliminary results of the study demonstrated that the proposed method can be readily extended for image-guided surgery of real patients.

• Journal of KIISE
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• v.43 no.7
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• pp.812-819
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• 2016

This paper introduces and analyzes the theoretical basis and method of the conventional initial-value assignment problem and feasibility of image segmentation. The paper presents topological evidence and a method of appropriate initial-value assignment based on topology theory. Subsequently, the paper shows minimum conditions for feasibility of image segmentation based on separation axiom theory of topology and a validation method of effectiveness for image modeling. As a summary, this paper shows image segmentation with its mathematical validity based on topological analysis rather than statistical analysis. Finally, the paper applies the theory and methods to conventional Gaussian random field model and examines effectiveness of GRF modeling.

• Journal of Korean Elementary Science Education
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• v.20 no.2
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• pp.229-237
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• 2001

The purpose of this study was to gain a suggestion how to educate pre-service elementary teachers in science education. One hundred and twenty three students were involved in the questionnaire to investigate the perception of science. Many of pre-service elementary teachers had a negative image of science. They consider science to be stiff, inflexible and dull. They suggested much more of foreign scientists than Korean ones as respectable scientists. They are very interested in science related to society, and themselves. It is necessary for elementary pre-service teachers to be educated to positively improve the images of science and scientist, and to understand modern scientific philosophical perspectives. And, Korean scientific history education should be educated formally or informally for them to count on about Korean scientists as respectable ones in science education.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2006.04a
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• pp.229-234
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• 2006

On May 31, 2003. Landsat 7 experienced an anomaly causing the Scan Line Corrector(SLC) to stop functioning normally. The SLC-off causes individual scan lines to alternately overlap and then leave large gaps at the edge of the Image. A many scientists with ongoing experience using ETM+ data evaluated the scientific usability and validity of Landsat 7 products containing the SLC anomaly The best reference scene for gap-filling is the other SLC-on Landsat scene that provide same resolution, few changes, and similar data acquisition. But receiving of Landsat imagery is not stable in Korea. So SPOT image can be another alternative solution because it is a steady-state multispectral satellite image as Landsat image. In this study, we filled the SLC-off gap s of 2, 3, 4 bands using SPOT image by a local regression technique, and assigned the optimum spectral value to gaps of 1, 5, 7 bands based on a spectral adjacency. Through this process, we could restore Landsat SLC-off image and evaluated the accuracy of the results.

• Journal of KIISE:Information Networking
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• v.34 no.3
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• pp.168-174
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• 2007

In this paper, we propose a reversible watermarking algorithm where an original image can be recovered from the watermarked image. Most watermarking algorithms cause degradation of image quality in original digital contents in the process of embedding watermarks. In the proposed algorithm, the original image can be obtained when the degradation is removed from the watermarked image after extracting watermark information. In the proposed algorithm, we utilize a peak point of image histogram and the location map and modify pixel values slightly to embed data. Because the peak point of image histogram and the location map are employed in this algorithm, there is no need of extra information transmitted to the receiving side. As the locations watermark embedding are identified using the location map, the amount of watermark data can increase through recursive embedding.