• KIPS Transactions on Software and Data Engineering
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• v.4 no.4
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• pp.177-186
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• 2015

For data fusion of laser range finder (LRF) and vision camera, accurate calibration of external parameters which describe relative pose between two sensors is necessary. This paper proposes a new calibration method which can acquires more accurate external parameters between a LRF and a vision camera compared to other existing methods. The main motivation of the proposed method is that any corner data of a known 3D structure which is acquired by the LRF should be projected on a straight line in the camera image. To satisfy such constraint, we propose a 3D geometric model and a numerical solution to minimize the energy function of the model. In addition, we describe the implementation steps of the data acquisition of LRF and camera images which are necessary in accurate calibration results. In the experiment results, it is shown that the performance of the proposed method are better in terms of accuracy compared to other conventional methods.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2022.06a
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• pp.205-208
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• 2022

Multi-exposure high dynamic range (HDR) image reconstruction, the task of reconstructing an HDR image from multiple low dynamic range (LDR) images in a dynamic scene, often produces ghosting artifacts caused by camera motion and moving objects and also cannot deal with washed-out regions due to over or under-exposures. While there has been many deep-learning-based methods with motion estimation to alleviate these problems, they still have limitations for severely moving scenes. They also require large parameter counts, especially in the case of state-of-the-art methods that employ attention modules. To address these issues, we propose a frequency domain approach based on the idea that the transform domain coefficients inherently involve the global information from whole image pixels to cope with large motions. Specifically we adopt Residual Fast Fourier Transform (RFFT) blocks, which allows for global interactions of pixels. Moreover, we also employ Depthwise Overparametrized convolution (DO-conv) blocks, a convolution in which each input channel is convolved with its own 2D kernel, for faster convergence and performance gains. We call this LFFNet (Lightweight Frequency Fusion Network), and experiments on the benchmarks show reduced ghosting artifacts and improved performance up to 0.6dB tonemapped PSNR compared to recent state-of-the-art methods. Our architecture also requires fewer parameters and converges faster in training.

• Korean Journal of Human Ecology
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• v.17 no.4
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• pp.707-721
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• 2008

The purpose of this study was to exam the effects of gender-role identity on adolescents' self esteem, clothing behaviors and favorite clothing image, focusing on analysis by adolescent' sex and age variable. The research method was survey and the subjects were 447 male and female adolescents in Daejeon, Korea. The questionnaire consisted of 4 measurement instruments (gender-role identity, self-esteem, clothing behaviors, and favorite clothing image) and subject' demographic attributions. The data were analyzed by factor analysis, $X^2$ test, t-test, ANOVA(analysis of variance), Duncan's multiple range test, and Pearson's correlation analysis, using SPSS program. The results are as follows. First, adolescents' gender-role identity and self- esteem were different by age rather than sex. Middle school students were represented by undifferentiated type while high school students were represented by androgynous type, and high school students had higher self-esteem than middle school students. Second, four factors emerged on clothing behaviors(clothing interest & psychological dependence, ostentation, conformity, and comfort), and favorite clothing image(characteristic, neat, active, and romantic image). Third, gender-role identity had important effects on self esteem; androgynous type had higher self esteem than other gender-role identity type. Forth, self-esteem had significant relationship with clothing behaviors and favorite clothing image, and these relationships were different by adolescent' sex and age variable. Fifth, gender-role identity had important effects on clothing behaviors; and rogynous type had more clothing interest, ostentation and comfort than any other gender-role identity type. Sixth, gender-role identity had important effects on favorite clothing images; androgynous type pursued more various clothing images than any other gender-role identity type.

• Journal of Multimedia Information System
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• v.5 no.3
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• pp.201-208
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• 2018

High Efficiency Video Coding range extensions (HEVC RExt) is a kind of extension model of HEVC. HEVC RExt was specially designed for dealing the high quality images. HEVC RExt is very essential for studio editing which handle the very high quality and various type of images. There are some problems to dealing these massive data in studio editing. One of the most important procedure is re-encoding and decoding procedure during the editing. Various codecs are widely used for studio data editing. But most of the codecs have common problems to dealing the massive data in studio editing. First, the re-encoding and decoding processes are frequently occurred during the studio data editing and it brings enormous time-consuming and video quality loss. This paper, we suggest new video coding structure for the efficient studio video editing. The coding structure which is called "ultra-low delay (ULD)". It has the very simple and low-delayed referencing structure. To simplify the referencing structure, we can minimize the number of the frames which need decoding and re-encoding process. It also prevents the quality degradation caused by the frequent re-encoding. Various fast coding algorithms are also proposed for efficient editing such as tool-level optimization, multi-serve based distributed coding and SIMD (Single instruction, multiple data) based parallel processing. It can reduce the enormous computational complexity during the editing procedure. The proposed method shows 9500 times faster coding speed with negligible loss of quality. The proposed method also shows better coding gain compare to "intra only" structure. We can confirm that the proposed method can solve the existing problems of the studio video editing efficiently.

• The Bulletin of The Korean Astronomical Society
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• v.41 no.2
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• pp.48.3-49
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• 2016

We have five different types of observation modes with regard to the Deep Ecliptic Patrol of the Southern Sky (DEEP-South); Opposition Census (OC) for targeted photometry, Sweet Spot Survey (S1) for discovery and orbit characterization of Atens and Atiras, Ecliptic Survey (S2) for asteroid family studies and comet census, NEOWISE follow-up (NW) for near simultaneous albedo measurements in the visible bands, and Target of Opportunity (TO) observation for follow-up either for unpredictable events or targets of special interests. Different exposures with such different modes result in a wide range of background noise level, the number of background stars and the mover's projected speed in each image. The Moving Object Detection Program (MODP) utilizes multiple mosaic images being taken for the same target fields at different epochs at the three KMTNet sites. MODP employs existing software packages such as SExtractor (Source-Extractor) and SCAMP (Software for Calibrating Astrometry and Photometry); SExtractor generates object catalogs, while SCAMP conducts precision astrometric calibration, then MODP determines if a point source is moving. This package creates animated stamp images for visual inspection with MPC reports, the latter for checking whether an object is known or unknown. We evaluate the astrometric accuracy and efficiency of MODP using the year one dataset obtained from DEEP-South operations.

• Journal of the Korea Fashion and Costume Design Association
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• v.16 no.1
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• pp.125-138
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• 2014

The purpose of this study was to investigate emotional images, preference, and purchasing intention on the color combination for knitwear cultural goods development. The subjects were 719 university students in Daejeon and Chungnam province, and the measuring instruments were 12 stimuli manipulated by the combination of chromatic and achromatic colors, and self-administrated questionnaires consisted of general color preference, emotional images, preference, and purchasing intention items of the knitwear cultural goods, and subjects' demographics attributions. The data were analyzed by Cronbach's ${\alpha}$, factor analysis, t test, ${\chi}^2$ test, ANOVA and Duncan's multiple range test, using SPSS program. The results were as follows. University students highly preferred black and gray color and deep tone on knitwear items, while they generally preferred blue and black color, and deep and pastel tone. The chromatic color combination was perceived as warm and conspicuous, but unattractive image. The achromatic color combination was perceived as cold and ordinary, but attractive image. Among the combination of chromatic and achromatic colors, gray & blue combination was perceived as more attractive image than red & dark gray combination. Color combination types of chromatic and achromatic color was showed some important differences on emotional image, preference and purchasing intention of knitwear cultural goods. Achromatic color combination was perceived as attractive image, and showed higher preference and purchasing intention than other color combination types.

• Korean Journal of Remote Sensing
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• v.30 no.5
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• pp.547-557
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• 2014

This paper presents a method for designing circular template used in similarity measurement for image registration. Circular template has translation and rotation invariant property, which results in correct matching of control points for image registration under the condition of translation and rotation between reference and sensed images. Circular template consisting of the pixels located on the multiple circumferences of the circles whose radii vary from zero to a certain distance, is converted to two-dimensional Discrete Polar Coordinate Matrix (DPCM), whose elements are the pixels of the circular template. For sensed image, the same type of circular template and DPCM are created by rotating the circular template repeatedly by a certain degree in the range between 0 and 360 degrees and then similarity is calculated using mutual information of the two DPCMs. The best match is determined when the mutual information for each rotation angle at each pixel in search area is maximum. The proposed algorithm was tested using KOMPSAT-2 images acquired at two different times and the results indicate high accurate matching performance under image rotation.

• Imaging Science in Dentistry
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• v.30 no.2
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• pp.101-108
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• 2000

Purpose : The effects of step numbers of copper wedge and exposure on the coefficient of determination (r²) of the conversion equation to Cu-equivalent image and on the Cu-equivalent value (mmCu) and it's coefficient of variation measured at each copper step and the mandibular premolar area were evaluated. Method: Digital image analyzing system consisted of scanner, personal computer, and a stepwedge with 10 steps of 0.03 mm copper in thickness as reference material was prepared for quantitative assessment of the bone mineral density. NIH image program was used for analyzing images. Results : The film having moderately high film density showed the discrepancy between the real thickness and the measured Cu-equivalent value of each copper step. The Cu-equivalent image was dependent on the determinational coefficient of the conversion equation than the coefficient of variance of the measured value. Conclusion : Obtaining conversion equation with high coefficient of determination and proper film exposure are supposed to be neccessary for quantitative assessment of bone density. Multiple steps in the range of the corresponding copper thickness to the bone density of the area to be measured should be prepared.

• Korean Journal of Human Ecology
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• v.19 no.1
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• pp.157-165
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• 2010

The purpose of this study was to investigate the awareness and practices for diet according to the lifestyles of college students in Youngnam region. The data were collected by self-administered questionnaires during May 2007. One hundred-ninety samples were analyzed by SPSS Windows. Frequencies, Cronbach's alpha, factor analysis, cluster analysis, one-way analysis of variance, Duncan's multiple range test and chi-square test were conducted. The results were as follows. Lifestyles were categorized into four factors by factor analysis: popularity-seeking type, body-management-seeking type, convenience-seeking type and healthy-seeking type. In addition, the respondents belonged to one of four groups by cluster analysis: body-management-seeking group, popularity-seeking group, convenience-seeking group, and healthy-seeking group. There were significant differences in perception about individual body images, concern of diet, awareness of diet necessity and knowledge and practices for diet among the four groups. That is, the body-management-seeking group showed the highest levels of concern of diet, awareness of diet necessity and the practice of fasting therapy. Additionally, the healthy-seeking group showed the highest level of practice of exercise therapy.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.24 no.1
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• pp.97-110
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• 2021

Vegetation index information is an important figure that is used in many fields such as landscape architecture, urban planning, and environment. Vegetation may vary slightly in vegetation vitality depending on photosynthesis and chlorophyll content. In this study, a range of vegetation worth preserving in the Taehwa River water system was determined, and hyperspectral images of drones were acquired (August, October), and the results were presented through DVI(Normalized Defference Vegetation Index), EVI(Enhanced Vegetation Index), PRI(Photochemical Reflectance Index), ARI (Anthocyanin Reflectance Index) index analysis. In addition, field spectral data and VRS-GPS(Virtual Reference System-GPS) surveys were performed to ensure the quality and location accuracy of the spectral band. As a result of the analysis, NDVI and EVI showed low vegetation vitality in October, -0.165 and -0.085, respectively, and PRI and ARI increased to 0.011 and 7.588 in October, respectively. For general vegetation vitality, it was suggested that NDVI and EVI analysis were effectively performed, and PRI and ARI were thought to be effective in analyzing detailed characteristics of plants by spectral band. It is expected that it can be widely used for park design and landscape information modeling by using drone image information construction and vegetation information.