• Journal of Korea Society of Digital Industry and Information Management
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• v.7 no.4
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• pp.119-131
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• 2011

In this paper, we explore the application of 2-D dual-tree discrete wavelet transform (DDWT), which is a directional and redundant transform, for image coding. DDWT main property is a more computationally efficient approach to shift invariance. Also, the DDWT gives much better directional selectivity when filtering multidimensional signals. The dual-tree DWT of a signal is implemented using two critically-sampled DWTs in parallel on the same data. The transform is 2-times expansive because for an N-point signal it gives 2N DWT coefficients. If the filters are designed is a specific way, then the sub-band signals of the upper DWT can be interpreted as the real part of a complex wavelet transform, and sub-band signals of the lower DWT can be interpreted as the imaginary part. The quincunx lattice is a sampling method in image processing. It treats the different directions more homogeneously than the separable two dimensional schemes. Quincunx lattice yields a non separable 2D-wavelet transform, which is also symmetric in both horizontal and vertical direction. And non-separable wavelet transformation can generate sub-images of multiple degrees rotated versions. Therefore, non-separable image processing using DDWT services good performance.

• Journal of Electrical Engineering and information Science
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• v.3 no.2
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• pp.202-210
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• 1998

This paper is concerned with an efficient generation of stereoscopic views for complex virtual environments by exploiting frame coherence in visibility. The basic idea is to keep visible polygons throughout the rendering process. P-buffer, a buffer of image size, holds the id of the visible polygon for each pixel. This contrasts to the frame buffer and the Z-buffer which hold the color information and the depth information, respectively. For the generation of a consecutive image, the position and the orientation of the visible polygons in the current view are updated according to the viewer's movements, and re-rendered on the current image under the assumption that, when the viewer moves slightly, the visibility of polygons remains unchanged. In the case of stereoscopic views, it may not introduce much difficulty when we render the right(left) image using visible polygons on the (right) image only, The less difference in two images is, the easier the matching becomes in perceiving depth. Some psychophysical experiments have been conducted to support this claim. The computational complexity for generating a fight(left) image from the previous left(right) image is bounded by the size of image space, and accordingly. It is somewhat independent of the complexity of the 3-D scene.

• Journal of Institute of Control, Robotics and Systems
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• v.21 no.8
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• pp.781-787
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• 2015

This paper proposes a hybrid visual servoing algorithm for the object tracking by a mobile robot with the stereo camera. The mobile robot with the stereo camera performs an object recognition and object tracking using the SIFT and CAMSHIFT algorithms for the hybrid visual servoing. The CAMSHIFT algorithm using stereo camera images has been used to obtain the three-dimensional position and orientation of the mobile robot. With the hybrid visual servoing, a stable balance control has been realized by a control system which calculates a desired angle of the center of gravity whose location depends on variations of link rotation angles of the manipulator. A PID controller algorithm has adopted in this research for the control of the manipulator since the algorithm is simple to design and it does not require unnecessary complex dynamics. To demonstrate the control performance of the hybrid visual servoing, real experiments are performed using the mobile manipulator system developed for this research.

• The Bulletin of The Korean Astronomical Society
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• v.41 no.1
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• pp.67.1-67.1
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• 2016

We observed two star forming regions, N159 and N160, in the Large Magellanic Cloud with SIRPOL, the polarimeter of the Infrared Survey Facility (IRSF) in South Africa. The photometric and polarimetric observations are done in three near-infrared bands, J, H, and Ks. We measured Stokes parameters of point sources and calculated their degrees of polarization and polarization angles. The polarization vector map shows complex features associated with dust and gas structures. Overall features of the magnetic field in N159 and N160 regions are different from each other and appear to be related to local environments, such as interior and boundary of shell structure, existence of star-forming HII regions, and boundaries between HII regions and dense dark clouds. We discuss the relation between the structure of magnetic field and the local properties of dust and gas in N159 and N160 regions by comparing our polarization vector map with images of $H{\alpha}$, mid-infrared, and $^{12}CO$ emissions, respectively by WFI of MPG/ESO telescope, Spitzer IRAC, and NANTEN.

• The Bulletin of The Korean Astronomical Society
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• v.41 no.1
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• pp.34.1-34.1
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• 2016

Galaxy clusters are the sites where the most massive galaxies are found, and so the most dramatic merger histories are embedded. Our deep (mu ~ 28 mag/arcsec^2) images of Abell 119 at z = 0.044 using the Blanco 4-m telescope at CTIO revealed post-merger signatures in ~35% of galaxies brighter than Mr < -19.5, suggesting that so many galaxies even in clusters have gone through galaxy mergers at recent epoch. We went further to understand the impact of mergers in cluster galaxies using stellar kinematics from the SAMI Integral Field Unit on the galaxies of Abell 119 in three aspects of kinematics : orientations, levels of rotation, and kinematic shapes. We found that 30% of the merger-featured galaxies show misalignment in the angle between the photometric major and the rotation axes, and most of them show complex kinematics. For comparison, only 5% of non-merger-featured galaxies show the misalignment. Moreover, our analysis using the Tully-Fisher relation shows that galaxy interactions can both enhance or reduce galaxy spin depending on the merger geometry. We present our preliminary result and discussion on the role of galaxy mergers in cluster environment from the perspective of kinematics.

• Journal of the Korean Institute of Intelligent Systems
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• v.23 no.2
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• pp.93-99
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• 2013

Fractal theory has been adopted as an effective tool for modelling complex and irregular natural phenomena facing in the fields of Computer Science, Engineering, Medical, Climatology and so on. In this paper, we presents an algorithm which enhances the performance of the triangular prism method(TPM) which has been widely used for fractal dimension extraction of natural terrains and images. For this, existing sampling methods are analyzed and a new sampling method which takes their merits is proposed. The effectiveness of the proposed algorithm is tested on fractal terrain maps and its performance is compared with that of other methods.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.30B no.4
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• pp.104-115
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• 1993

The motion compensated coding (MCC) technique, which exploits the temporal redundancies in the moving images with the motion estimation technique,is one of the most popular techniques currently used. Recently, a variable block size(VBS) motion estimation scheme has been utilized to improve the performance of the motion compensted coding. This scheme allows large blocks to the used when smaller blocks provide little gain, saving rates for areas containing more complex motion. Hence, a new VBS motion estimation scheme with a hierarchical structure is proposed in this paper, in order to combine the motion vector coding technique efficiently. Topmost level motion vector, which is obtained by the gain/cost motion estimation technique with selective motion prediction method, is always transmitted. Thus, the hierarchical VBS motion estimation scheme can efficiently exploit the redundancies among neighboring motion vectors, providing an efficient motion vector encoding scheme. Also, a restricted search with respect to the topmost level motion vector enables more flexible and efficient motion estimation for the remaining lower level blocks. Computer simulations on the high resolution image sequence show that, the VBS motion estimation scheme provides a performance improvement of 0.6~0.7 dB, in terms of PSNR, compared to the fixed block size motion estimation scheme.

• Proceedings of the KIEE Conference
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• 2007.10a
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• pp.155-156
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• 2007

This paper presents the vision-based camber and optimal cutting line detection algorithm for hot-rolling process. It is important to measure the camber of head and tail part of strips because many problems are caused by the camber in the hot-rolling process. The hot-rolling process has time constraints. The camber detection algorithm of head and tail parts requires fast and less complex for satisfying time constraints. The proposed algorithm consists of two parts: measurement of the camber in the head and tail part of strips and decision part of the optimal cutting line of hot-rolled strip. First, we obtain the camber value of the strip from the difference between the real center line and the center line of head, tail part. Second, the head and tail part of strips isn't suitable for strips connections. Therefore, the cutting process is needed in the hot-rolling process. The optimal cutting line is determined by the head and tail images obtained from cameras. The algorithm is applied into the vision system with two area cameras, Matrox image processing board and host PC for verification.

• Korean Institute of Interior Design Journal
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• v.23 no.4
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• pp.52-62
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• 2014

The rapid growth of economy improves not only the life quality of people in this modern society but also standards of value in connection with how those people would spend money as they engage in various leisure and cultural activities. That being the case, hotels are currently changing into places of new concepts depending on those new lifestyles of these people, and in those new places, people can entertain and experience as enjoying cultures. The marketing collaboration of the hotels with brands can be used as a more inclusive way to enhance brand images. In addition, as having infinite possibilities of the collaboration's being able to create a new-concept space with an identity of a brand included, this collaboration makes it possible for the design hotels to decorate their interior spaces differently from those of other hotels. In the light of that, the brand collaboration is basically divided into three groups which are the fashion collaboration, the technique collaboration and the designer collaboration, and the brand collaboration is also able to express the interior spaces of the design hotels as working on those six components, such as reproduction, events, alteration, messages, culture and image. After all, through the brand collaboration marketing, this thesis expects an interior design of a new-concept design hotel which would play a role as a complex cultural space.

• Korean Institute of Interior Design Journal
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• v.26 no.6
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• pp.126-134
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• 2017

Since public rental housings (social housings) in Korea are extremely standardized and uniformed, a variety of needs of residents for their housing are hardly satisfied. Public rental housing conditions, its low quality and size limitations regardless of residents type and needs resulted into negative images of social housing and social discriminations. Therefore there is a growing demand for alternative housing options in terms of diversification of social housing design with consideration for changing households and housing requirements. The purpose of this study to investigate some housing design guidelines, to analyze layout of building complex, community designs, household units and characteristics, overall design characteristics (sustainable design features, facade design, window and balcony composition, color and materials) and to provide some design suggestions for social housing. Design guidelines are classified into site planning and building layouts, residential building and household units, and performance of housing. Community facilities and their design features provide uniqueness of the public residence. Overall housing size of foreign cases is bigger than the domestic cases. Narrow shape of household units are more dominant in Korean public rental housing. More various shape and forms are found in facade and window design in foreign cases. Some design suggestion are provided for more diverse housing units and design for public rental housing in Korea.