• Journal of Korean Ophthalmic Optics Society
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• v.10 no.4
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• pp.305-312
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• 2005

In this thesis, Lohmann's algorithm and FFT (fast Fourier transform) are used to synthesize binary-phase holograms. FFT computing is carried out for the calculation of complex wavefronts of $128{\times}128$ sampling points of an object that is numerically specified. Then using the Lohmann's algorithm, the amplitude and the phase of complex wavefronts are encoded in binary holograms on each sampling points. PC (personal computer) and laser printer are used to plot binary-phase holograms and CGH (computer generated holograms) films are obtained from this plot by photographic reduction. Holographic images of numerically specified objects are reconstructed from the He-Ne laser and the inverse Fourier optics system. We estimate the quality of holographic images according to the sampling number, application of random phase, amplitude clipping and bleaching the CGH film. We derive optimized conditions to reconstruct better holographic images and to reduce the speckle noise. FFT and Lohmann's algorithm are implemented with MS Visual BASIC 6.0 for the programming of binary-phase hologram.

• Publications of The Korean Astronomical Society
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• v.20 no.1 s.24
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• pp.55-62
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• 2005

The First Generation Digitized Sky Survey (DSS-I) is a collection of digitized photographic atlases of the night sky taken from the Palomar Observatory (northen sky) and the Anglo-Australian Observatory (southern sky). DSS-I is widely used by the astronomical community for a number of applications including object cross-identification and astrometry. However, accessing and retrieving the actual images are nontrivial owing to the huge size (> 60 GB) of the dataset. To facilitate retrieval process of DSS-I data for the public, Korean Astronomical Data Center (KADC) developed a web application that provides not only data retrieval but also visualization functions. The web application consists of several modules developed using Java Applet, Jave Servlet, and JaveServer Pages (JSP) technologies. It allows users to retrieve images efficiently in various formats such as FITS, JPEG, GIF, and TIFF, and also offers an interactive visulization tool, ImgViewer, for displaying/analyzing FITS images. To use the web application, users require a Java-enabled web browser.

• Cartoon and Animation Studies
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• s.32
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• pp.315-333
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• 2013

This study aims to investigate that today's Mixed Reality Technology did not appear suddenly but has its beginnings in 20th century Visual and Interactive Art. First, Photographic Art expressed three-D on the two-dimensional plane and mixed images of reality and virtuality. Photogram made people experience both two-dimensional images and three-dimensional effects concurrently, and Photomontage combined various photos and mixed reality and virtuality. Next, Cinema tried to combine virtuality and reality using objets and CG. Early Cinema composed films and real objets. As computer technology developed, Cinema composed objet CG on real images and then tried background CG compositing. Finally, Telepresence Art tried a new possibility of Mixed Reality breaking the boundary between reality and virtuality, subject and object. It oscillates between virtual space in reality and real space in virtuality, or represents Mixed Reality by remote control of long distance participants. In the future, for the development and direction of Mixed Reality, there will be more need of referring to Visual and Interactive Art.

• Imaging Science in Dentistry
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• v.36 no.1
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• pp.49-54
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• 2006

Purpose : To evaluate accuracy and reliability of program to measure facial soft tissue thickness using 3D computed tomographic images by comparing with direct measurement. Materials and Methods : One cadaver was scanned with a Helical CT with 3 mm slice thickness and 3 mm/sec table speed. The acquired data was reconstructed with 1.5 mm reconstruction interval and the images were transferred to a personal computer. The facial soft tissue thickness were measured using a program developed newly in 3D image. For direct measurement, the cadaver was cut with a bone cutter and then a ruler was placed above the cut side. The procedure was followed by taking pictures of the facial soft tissues with a high-resolution digital camera. Then the measurements were done in the photographic images and repeated for ten times. A repeated measure analysis of variance was adopted to compare and analyze the measurements resulting from the two different methods. Comparison according to the areas was analyzed by Mann-Whitney test. Results : There were no statistically significant differences between the direct measurements and those using the 3D images (p>0.05). There were statistical differences in the measurements on 17 points but all the points except 2 points showed a mean difference of 0.5 mm or less. Conclusion : The developed software program to measure the facial soft tissue thickness using 3D images was so accurate that it allows to measure facial soft tissues thickness more easily in forensic science and anthropology.

• Journal of the HCI Society of Korea
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• v.14 no.1
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• pp.5-13
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• 2019

SNS has been advanced from first to third generation by changing its service format in various ways. Nowadays, image-based SNS such as instagram and pinterest where users communicate via images has become popular as third generation service. Due to the fact that users communicate especially through images, image-based SNS utilizes images in different ways compared to other SNS. This study derived various characteristics of images in image-based SNS, and observed how users perceive each of them differently. Also, relationship between the characteristics and user satisfaction on image-based SNS is analyzed. The characteristics include 6 items; 'implicity', 'recordability', 'expressing identity', 'indirect experience', 'temporary amusement', and 'stimulating desire.' As a result of comparing user perception regarding those 6 characteristics, recordability and indirect experience were highly recognized than other characteristics. Also, according to users' age, motivation of using image-based SNS, and number of followers they have, users perceived each characteristic in different level. Finally, relationship between the characteristics and user satisfaction was analyzed, and the result showed that indirect experience had positive influence to user satisfaction. Regarding indirect experience, it was highly perceived by users and also had positive influence to their satisfaction, which means it is the most typical characteristic of image-based SNS.

• 제어로봇시스템학회:학술대회논문집
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• 1996.10a
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• pp.438-441
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• 1996

Spinal deformity is a serious disease especially for teenagers and it is desirable for school children to be checked possible spinal deformity by moire photographic inspection method. The moire images of children's backs are visually inspected by doctors, which may cause misjudge because of a large amount of data they have to examine. A technique is proposed in this paper for automating this inspection by computer. Two characteristic axes, a potential symmetry axis approximating the human middle line and a principal axis representing the direction of a moire pattern are employed. Two principal axes are extracted locally on a back and their gradients against the potential symmetry axis are calculated. These gradients compose a 2D feature space and a linear discriminant function (LDF) is defined there which separates normal cases from suspicious cases. The LDF defined by 40 training, data was employed in the experiment to examine 40 test data and 77.5% of them were classified correctly. This amounts to 88.8% if the training data is included.

• Journal of Korea Multimedia Society
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• v.12 no.11
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• pp.1539-1546
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• 2009

According to photography, lines are important elements that make composition and mood of photo. In this paper, we proposed a measure for compositional dissimilarity between photos using lines which are basic elements of photography. To identify patterns of lines which classify composition of photos, we investigated both features of compositionally same photos and compositionally different photos. Then we developed effective measure for compositional dissimilarity between photos by applying the investigated features to the measure, and we implemented an image searching system which retrieves photo compositionally similar to given query to evaluate performance of proposed method. The searching system showed the precision of about 85% maximally for the highly matched 10 results and was capable of reliably retrieving compositionally similar to given query even if some objects were included in photos.

• Current Industrial and Technological Trends in Aerospace
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• v.6 no.2
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• pp.80-89
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• 2008

Photogrammetry is a non-direct 3-dimensional coordinate measurement technique using 2-dimensional photographic images. For reconstruction 3-dimensional data from the 2-dimensional photos, photogrammetry uses the fundamental principle of triangulation. Digital photogrammetry solve for the camera location and coordinates simultaneously through the mapping, scaling and bundle processing in software processing. In this paper, several applications for photogrammetry measurement are introduced, such as 'photogrammetric measurement of the gravity deformation of a cassegrain type antenna', 'analysis of photogrammetry data from ISIM mockup', 'underwater photogrammetric verification of nuclear fuel assemblies', 'spacecraft optical bench measurement' and 'spacecraft ground support equipment measurement'.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.2
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• pp.1134-1147
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• 2017

With the rise in popularity of photographic and video cameras, an increasing number of fields are now using thermal imaging cameras. One such application is in the diagnosis of breast cancer, as thermal imaging provides a low-cost and noninvasive method. Thermal imaging is particularly safe for pregnant women, and those with large, dense, or sensitive breasts. In addition, excessive doses of radiation, which may be used in traditional methods of breast cancer detection, can increase the risk of cancer. This paper presents one method of breast cancer detection. Breast images were taken using a thermal camera, with preliminary experiments conducted on Cambodian women. Then the experimental results were analyzed and compared using Shannon entropy and logistic regression.

• Korean journal of applied entomology
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• v.44 no.1 s.138
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• pp.13-20
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• 2005

Thirty-four species of the subfamily Plusiinae were recognized from the lepidopteran expeditions to Mt. Changbai during 2000-2004. Among them, six species (Abrostola ussuriensis Dufay, Polychrysia aurata (Staudinger), P. splendida (Butler), Lamprotes mikadina (Butler), Autographa amurica (Staudinger), and A. v-minus (Oberthur)) are reported for the first time from China. Three previously reported species Antoculeora ornatissima (Walker), Autographa nigrisigna (Walker), and Syngrapha hochenwarthi (Hochenwarth) were not found in this study, Photographic images of adults of the newly known species from China and their male or female genitalia are given, with a check list of the 37 known species of the subfamily in Mt Changbai.