• 대한공간정보학회지
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• 제10권1호
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• pp.91-100
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• 2002

최근 도로시설물관리 시스템의 구축이 많이 이루어지고 있으며, 이 과정에서 수치지도는 공간 자료기반 구축을 위한 필수 자료로 사용된다. 그러나, 기존 지형도나 준공도면 자료가 시스템 구축용으로 충분하지 않은 경우에는 수치지도의 작성과 수정 및 갱신에 난관을 겪는 사례가 적지 않다. 본 연구에서는 항공사진 및 지상사진 등 다양한 형태의 영상자료를 이용하여 도로시설물 정보를 추출하고자 하였다. 지상취득 영상으로는 현재 많이 쓰이고 있으며 비교적 저가품인 일반카메라, 디지털카메라, 비디오카메라에 의하여 촬영된 단사진 영상을 이용하였고, 여기서 추출한 공간자료와 속성자료는 자료기반의 수정과 갱신에 사용하였다. 아울러 단사진 영상으로부터 추출한 공간자료를 이용하여 상대적인 척도로서 수치지도의 생성 가능성을 타진하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 심포지엄 논문집 정보 및 제어부문
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• pp.45-47
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• 2006

Cleft palate is a congenital deformity condition with separation of the two sides of the lip resulting in nose deformity. Evaluation of surgical corrections and outcome assessments for nose deformity due to the cleft lip depends mainly on doctor's subjective judgment. An objective method for evaluation of the condition and surgical outcome of nose deformity due to the cleft palate is needed. This study aimed at objective assessment of a cleft palate nose deformity condition by analyzing the following parameters obtained from photographic images of a cleft palate patients: (1) angle difference between two nostril axes. (2) center of the nostril and distance between two centers. (3) overlapped area of two nostrils, and (4) the overlapped area ratio of the two nostrils. A regression equation of doctor's grades was obtained using the eight parameters. Three plastic surgeons gave us the grades for the each photographic image by 10 increments with maximum grade of 100. The average reproducibility of the grades given by the three plastic surgeons and the three laymen using the developed program was $10.8{\pm}4.6%$ and $7.4{\pm}1.8%$, respectively. Kappa values representing the degree of consensus of the plastic surgeons and the three laymen were 0.43 and 0.83. respectively. Correlation coefficient of the grades evaluated by the surgeons and obtained by the neural network was 0.798. In conclusion. the developed neural network model provided us better reproducibility and much better consensus than doctor's subjective evaluation in addition to objectiveness and easy application.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제5권7호
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• pp.1311-1328
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• 2011

We re-render a photographic image as a simulated pencil drawing using two independent line integral convolution (LIC) algorithms that express tone and feature lines. The LIC for tone is then applied in the same direction across the image, while the LIC for features is applied in pixels close to each feature line in the direction of that line. Features are extracted using the coherent line scheme. Changing the direction and range of the LICs allows a wide range of pencil drawing style to be mimicked. We tested our algorithm on diverse images and obtained encouraging results.

• 한국측량학회:학술대회논문집
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• 한국측량학회 2006년도 춘계학술발표회 논문집
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• pp.217-222
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• 2006

In this study, we performed three dimensional(3-D) modeling and simulation of terrain surfaces by using large scale aerial photographs. The objectives of this study are to use landscape analysis including 3-D database of built environments. The test area is selected around Olympic stadium located in Susung-gu, Daegu. A 1:5,000 scale of ortho-photo map is generated by photogrammetric procedures from 1:20,000 scale of aerial photographs, Digital Elevation Model (DEM) is also extracted from stereo aerial photographs or digital maps. The heights of buildings are determined using GPS control survey and aerial photographs in the test area, DEMs are extracted from the digital map. And then the two are combined three-dimensional changes of landscape views of buildings with terrain are simulated.

• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1994년도 추계학술대회
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• pp.92-95
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• 1994

As computer systems to make medical practice easy are widely used, a special hardware system processing medical data fast becomes more important. To meet the urgent demand for high speed image processing, especially image compression and decompression, we designed and implemented the medical image CODEC (COder/BECoder) based on MISD(Multiple Instruction Single Data stream) architecture to adopt parallelism in it. Considering not being a standart scheme of medical mage compression/decompress ion, the CODEC is designed programable and general. In this paper, we use JPEG (Joint Photographic Experts Group) algorithm to process images fast and evalutate it.

• 한국멀티미디어학회:학술대회논문집
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• 한국멀티미디어학회 2012년도 춘계학술발표대회논문집
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• pp.340-342
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• 2012

Integral Imaging (II) is an attractive technique for three-dimensional (3D) image, video display and recording. Inherently, the high resolution II requires an enormous amount of data for storing and transmitting of 3D scenes. Compression techniques attempt to evade this issue. In this study, we made a comparative performance analysis of popular transforming/compression techniques such as the Discrete Cosine Transform (DCT) and the Discrete Wavelet Transform (DWT) in order to compress 3D-II. The standard baseline JPEG (Joint Photographic Experts Group) using DCT and JPEG 2000 using DWT methods were manipulated in our experiments. In our analysis, we have shown that the DWT based JPEG 2000 compression methodology could be a good alternative for 3D-II.

• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1992년도 춘계학술대회
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• pp.58-63
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• 1992

The discrete cosine transform (DCT)-based progressive coding standard proposed by the International Standardization Orgnnization (ISO) Joint Photographic Experts Groups (JPEG) is investigated for medical image compression and the performance of the JPEG is compared to that of the full-frame bit-allocation (FFBA) technique. From the comparison, the JPEG standard appeals superior to the FFBA technique in the following aspects: 1) JPEG achieves higher compression than the FFBA technique with less mean square error. 2) Less Gibb's artifact is observed in the compressed images by the JPEG. 3) Computational time for the JPEG is about one-fourth or the FFBA technique. Other attractive points of the JPEG include: Implementation of the JPEG with VLSIs is commercially available in relative low price and the JPEG compression format can easily be interchangeable with other applications.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 춘계학술대회논문집B
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• pp.692-697
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• 2000

In Particle Tracking Velocimetry, the analysis of double-exposed photographic plate can be carried out either by means of Young's fringe analysis or by a digital image processing technique. In this study, we used digital image processing to two images in one frame far analyzing in-cylinder flow fields, and compared PTV with PSV(Particle Streak Velocimetry). Additionally, this technique was verified by two different calibration method. One is interpolation by invert distance, the other is interpolation by area ratio. Finally, the results between two interpolation methods were similar in whole flow fields.

• 한국산업정보학회:학술대회논문집
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• 한국산업정보학회 1997년도 추계학술대회 발표논문집:21세기를 향한 정보통신 기술의 전망
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• pp.91-101
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• 1997

The demand for handling images in digital form has increased dramatically in recent years. Digital image compression is required to store and transmit mass information in different from general information. JPEG(Joint Photographic Experts Group) committee founded by CCITT and ISO is define the still-image standard compression/restoration algorithm. JPEG is proposed the standard of grayscale and color still-image compression/restoration. In the image quality, JPEG is applicable to the various applications in which compression is able to from 1/10 to 1/50 without the visible obstacle. In this paper, we proposed that the proposed method enhance the compression ratio which is reducing the higher frequency in order to increasing the spatial redundancy in the image. The proposed method is using the low pass filter in order to reducing the higher frequency. The low-pass filters are using the median filter and convolution filter in the spatial domain, FFT filter in the frequency domain. We acquired the additive compression ratio reducing the higher frequency using the low-pass filter.

• 한국분무공학회지
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• 제18권1호
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• pp.1-8
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• 2013

In this paper an experimental study is presented to investigate the dynamic behavior of impacting droplet onto a liquid film. The main parameters are the droplet velocity and the thickness of the liquid film. Photographic images are presented to show the formation of crown, central jet and disintegrating droplet from the central jet. The emphasis is on presenting the time evolution of crown diameter, crown height, central jet height and the size of disintegrating droplet from the central jet. The diameter and height of crown are higher for faster droplet and thinner liquid film. On the other hand, the height of central jet are higher for faster droplet and thicker liquid film. The size of disintegrating droplet from the central jet heavily depends on the droplet velocity; Larger droplet is produced with faster falling droplets.