• Title/Summary/Keyword: feature reconstruction

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Model-independent constraints on the light-curve parameters and reconstructions of the expansion history from Type Ia supernovae

  • Koo, Hanwool;Shafieloo, Arman;Keeley, Ryan;L'Huillier, Benjamin
    • The Bulletin of The Korean Astronomical Society
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    • v.44 no.2
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    • pp.54.1-54.1
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    • 2019
  • We use iterative smoothing reconstruction method along with exploring in the parameter space of the light curves of the JLA supernova compilation (Joint Light-curve Analysis) to simultaneously reconstruct the expansion history of the universe as well as putting constrains on the light curve parameters without assuming any cosmological model. Our constraints on the light curve parameters of the JLA from our model-independent analysis seems to be closely in agreement with results assuming ΛCDM cosmology or using Chevallier-Polarski-Linder (CPL) parametrization for the equation of state of dark energy. This implies that there is no hidden significant feature in the data that could be neglected by cosmology model assumption. The reconstructed expansion history of the universe and properties of dark energy seems to be in good agreement with expectations of the standard ΛCDM model. Our results also indicate that the data allows a considerable flexibility for expansion history of the universe.

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Multiresolutional Reconstruction from Contours (윤곽선을 이용한 다중해상도적 복원)

  • 민경하;이인권
    • Journal of KIISE:Computer Systems and Theory
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    • v.30 no.11
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    • pp.629-654
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    • 2003
  • A new multiresolutional scheme that reconstructs a polygonal mesh from the set of contours is presented. In the first step, we apply a radial gradient method to extract the contours on the sampled slices from a volume data. After classifying the types of the edges on the contours, we represent the contour using the context-free grammar. The polygons between two neighboring contours are generated through the traversal of the derivation trees of the context-free grammar. The polygonal surface of the coarsest resolution is refined through the refinement of the contours, which is executed by casting more rays on the slices. The topologies between the polygonal surfaces of various resolutions are maintained from the fact that the radial gradient method preserves the topologies of the contours of various resolutions. The proposed scheme provides efficient computation and compression methods for the tiling procedure with the feature preservation.

3D surface Reconstruction of Moving Object Using Multi-Laser Stripes Irradiation (멀티 레이저 라인 조사를 이용한 비등속 이동물체의 3차원 형상 복원)

  • Yi, Young-Youl;Ye, Soo-Young;Nam, Ki-Gon
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.44 no.2 s.314
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    • pp.144-152
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    • 2007
  • We propose a 3D modeling method for surface inspection of non-linear moving object. The laser lines reflect the surface curvature. We can acquire 3D surface information by analyzing projected laser lines on object. ill this paper, we use multi-line laser to make use of robust of single stripe method and high speed of single frame. Binarization and channel edge extraction method were used for robust laser line extraction. A new labeling method was used for laser line labeling. We acquired sink information between each 3D reconstructed frame by feature point matching, and registered each frame to one whole image. We verified the superiority of proposed method by applying it to container damage inspection system.

The Natural Environment during the Last Glacial Maximum Age around Korea and Adjacent Area

  • Yoon, Soon-Ock;Hwang, Sang-Ill
    • The Korean Journal of Quaternary Research
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    • v.17 no.2
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    • pp.33-38
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    • 2003
  • This study is conducted to examine the data of climate or environmental change in the northeastern Asia during the last glacial maximum. A remarkable feature of the 18,000 BP biome reconstructions for China is the mid-latitude extention of steppe and desert biomes to the modem eastern coast. Terrestrial deposits of glacial maximum age from the northern part of Yellow Sea suggest that this region of the continental shelf was occupied by desert and steppe vegetation. And the shift from temperate forest to steppe and desert implies conditions very much drier than present in eastern Asia. Dry conditions might be explained by a strong winter monsoon and/or a weak summer monsoon. A very strong depression of winter temperatures at LGM. has in the center of continent has influenced in northeast Asia similarly. The vegetation of Hokkaido at LGM was subarctic thin forest distributed on the northern area of middle Honshu and cool and temperate mixed forest at southern area of middle Honshu in Japan. The vegetation landscape of mountain- and East coast region of Korea was composed of herbaceous plants with sparse arctic or subarctic trees. The climate of yellow sea surface and west region of Korea was much drier and temperate steppe landscape was extended broadly. It is supposed that a temperate desert appeared on the west coast area of Pyeongan-Do and Cheolla-Do of Korea. The reconstruction of year-round conditions much colder than today right across China, Korea and Japan is consistent with biome reconstruction at the LGM.

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Creative idea generation methods by analogical association and shape elements reconstruction (유추적 연합과 형태요소 재구성에 의한 창의적 아이디어 발상법)

  • Hong, Jung-Pyo;Choi, Eun-Hee
    • Science of Emotion and Sensibility
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    • v.10 no.3
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    • pp.443-450
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    • 2007
  • Design is a realm one should have brought out creativity. So designers have continuously struggled for creating something new. In respects of that the essence of design work is making novel and creative things, and in design process' creative idea generation' to reach a final design solution is one of important capability that designers must have. In this study two different substantial methods for creative idea generation are suggested. One is existing' analogical association', an essential form widely used in association process, another is 'shape elements reconstruction' similarly operated 'shape grammar'. Therefore in this study for finding methods to reinforce designers' creative idea generation both of paper-based and computer-based design method are suggested substantially. In Both there is a common feature that existing or quiet new elements are organizationally associated or reconstructed in idea generation procedure.

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Geometric Regualrization of Irregular Building Polygons: A Comparative Study

  • Sohn, Gun-Ho;Jwa, Yoon-Seok;Tao, Vincent;Cho, Woo-Sug
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.25 no.6_1
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    • pp.545-555
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    • 2007
  • 3D buildings are the most prominent feature comprising urban scene. A few of mega-cities in the globe are virtually reconstructed in photo-realistic 3D models, which becomes accessible by the public through the state-of-the-art online mapping services. A lot of research efforts have been made to develop automatic reconstruction technique of large-scale 3D building models from remotely sensed data. However, existing methods still produce irregular building polygons due to errors induced partly by uncalibrated sensor system, scene complexity and partly inappropriate sensor resolution to observed object scales. Thus, a geometric regularization technique is urgently required to rectify such irregular building polygons that are quickly captured from low sensory data. This paper aims to develop a new method for regularizing noise building outlines extracted from airborne LiDAR data, and to evaluate its performance in comparison with existing methods. These include Douglas-Peucker's polyline simplication, total least-squared adjustment, model hypothesis-verification, and rule-based rectification. Based on Minimum Description Length (MDL) principal, a new objective function, Geometric Minimum Description Length (GMDL), to regularize geometric noises is introduced to enhance the repetition of identical line directionality, regular angle transition and to minimize the number of vertices used. After generating hypothetical regularized models, a global optimum of the geometric regularity is achieved by verifying the entire solution space. A comparative evaluation of the proposed geometric regulator is conducted using both simulated and real building vectors with various levels of noise. The results show that the GMDL outperforms the selected existing algorithms at the most of noise levels.

Effective Reconstruction of Stereo Image through Regularized Adaptive Disparity Estimation Scheme (평활화된 적응적 변이추정 기법을 이용한 스테레오 영상의 효과적인 복원)

  • Kim, Yong-Ok;Bae, Kyung-Hoon;Kim, Eun-Soo
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.28 no.4C
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    • pp.424-432
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    • 2003
  • In this paper, an effective method of stereo image reconstruction through the regularized adaptive disparity estimation is proposed. Althougth the conventional adaptive disparity estimation method can sharply improve the PSNR of a reconstructed stereo image, but some problems of overlapping between the matching windows and disallocation of the matching windows can be occurred, because the matching window size changes adaptively in accordance with the magnitude of feature values. Accordingly, in thia paper, a new regularized adaptive disparity estimation technique is proposed. That is, by regularizing the estimated disparity vector with the neughboring disparity vectors, problems of the conventional adaptive disparity estimated scheme might be solved, and also the predicted stereo image can be more effectively reconstructed. From some experiments using the CCETT'S stereo image pairs of 'Man' and 'Claude', it is analyzed that the proposed disparity estimation scheme can improve PSNRs of the reconstructed images to 10.89dB, 6.13dB for 'Man' and 1.41dB, 0.81dB for 'Claude' by comparing with those of the conventional pixel-based and adaptive estimation method, respectively.

3D Visualization of Brain MR Images by Applying Image Interpolation Using Proportional Relationship of MBRs (MBR의 비례 관계를 이용한 영상 보간이 적용된 뇌 MR 영상의 3차원 가시화)

  • Song, Mi-Young;Cho, Hyung-Je
    • The KIPS Transactions:PartB
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    • v.10B no.3
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    • pp.339-346
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    • 2003
  • In this paper, we propose a new method in which interpolation images are created by using a small number of axiai T2-weighted images instead of using many sectional images for 3D visualization of brain MR images. For image Interpolation, an important part of this process, we first segment a region of interest (ROI) that we wish to apply 3D reconstruction and extract the boundaries of segmented ROIs and MBR information. After the image size of interpolation layer is determined according to the changing rate of MBR size between top slice and bottom slice of segmented ROI, we find the corresponding pixels in segmented ROI images. Then we calculate a pixel's intensity of interpolation image by assigning to each pixel intensity weights detected by cube interpolation method. Finally, 3D reconstruction is accomplished by exploiting feature points and 3D voxels in the created interpolation images.

A Study on the Asphalt Road Boundary Extraction Using Shadow Effect Removal (그림자영향 소거를 통한 아스팔트 도로 경계추출에 관한 연구)

  • Yun Kong-Hyun
    • Korean Journal of Remote Sensing
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    • v.22 no.2
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    • pp.123-129
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    • 2006
  • High-resolution aerial color image offers great possibilities for geometric and semantic information for spatial data generation. However, shadow casts by buildings and trees in high-density urban areas obscure much of the information in the image giving rise to potentially inaccurate classification and inexact feature extraction. Though many researches have been implemented for solving shadow casts, few studies have been carried out about the extraction of features hindered by shadows from aerial color images in urban areas. This paper presents a asphalt road boundary extraction technique that combines information from aerial color image and LIDAR (LIght Detection And Ranging) data. The following steps have been performed to remove shadow effects and to extract road boundary from the image. First, the shadow regions of the aerial color image are precisely located using LEAR DSM (Digital Surface Model) and solar positions. Second, shadow regions assumed as road are corrected by shadow path reconstruction algorithms. After that, asphalt road boundary extraction is implemented by segmentation and edge detection. Finally, asphalt road boundary lines are extracted as vector data by vectorization technique. The experimental results showed that this approach was effective and great potential advantages.

A study of extended processor trace decoder structure for malicious code detection (악성코드 검출을 위한 확장된 프로세서 트레이스 디코더 구조 연구)

  • Kang, Seungae;Kim, Youngsoo;Kim, Jonghyun;Kim, Hyuncheol
    • Convergence Security Journal
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    • v.18 no.5_1
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    • pp.19-24
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    • 2018
  • For a long time now, general-purpose processors have provided dedicated hardware / software tracing modules to provide developers with tools to fix bugs. A hardware tracer generates its enormous data into a log that is used for both performance analysis and debugging. Processor Trace (PT) is a new hardware-based tracing feature for Intel CPUs that traces branches executing on the CPU, which allows the reconstruction of the control flow of all executed code with minimal labor. Hardware tracer has been integrated into the operating system, which allows tight integration with its profiling and debugging mechanisms. However, in the Windows environment, existing studies related to PT focused on decoding only one flow in sequence. In this paper, we propose an extended PT decoder structure that provides basic data for real-time trace and malicious code detection using the functions provided by PT in Windows environment.

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