• Investigative Magnetic Resonance Imaging
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• v.20 no.3
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• pp.181-184
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• 2016

Short inversion time inversion recovery (STIR) is widely used for spinal magnetic resonance imaging (MRI) because the pulse sequence of STIR is insensitive to magnetic field inhomogeneity and can be used to scan a large field of view. In this case report, we present a case of spinal epidural hematoma with unexpected signal decrease on a STIR image. The MRI showed an epidural mass that appeared with high signal intensity on both T1- and T2-weighted images. However, a signal decrease was encountered on the STIR image. This nonspecific decrease of signal in tissue with a short T1 relaxation time that is similar to that of fat (i.e., hemorrhage) could lead to a diagnostic pitfall; one could falsely diagnose this decrease of signal as fat instead of hemorrhage. Awareness of the nonselective signal suppression achieved with STIR pulse sequences may avert an erroneous diagnosis in image interpretation.

• Parasites, Hosts and Diseases
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• v.45 no.3
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• pp.165-174
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• 2007

Toxoplasma gondii GRA10 expressed as a GFP-GRA10 fusion protein in HeLa cells moved to the nucleoli within the nucleus rapidly and entirely. GRA10 was concentrated specifically in the dense fibrillar component of the nucleolus morphologically by the overlap of GFP-GRA10 transfection image with IFA images by monoclonal antibodies against GRA10 (Tg378), B23 (nucleophosmin) and C23 (nucleolin). The nucleolar translocalization of GRA10 was caused by a putative nucleolar localizing sequence (NoLS) of GRA10. Interaction of GRA10 with TATA-binding protein associated factor 1B (TAF1B) in the yeast two-hybrid technique was confirmed by GST pull-down assay and immunoprecipitation assay. GRA10 and TAF1B were also co-localized in the nucleolus after co-transfection. The nucleolar condensation of GRA10 was affected by actinomycin D. Expressed GFP-GRA10 was evenly distributed over the nucleoplasm and the nucleolar locations remained as hollows in the nucleoplasm under a low dose of actinomycin D. Nucleolar localizing and interacting of GRA10 with TAF1B suggested the participation of GRA10 in rRNA synthesis of host cells to favor the parasitism of T. gondii.

• Journal of the Korea Society of Computer and Information
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• v.8 no.4
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• pp.63-68
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• 2003

Almost the system are usually taken by means of shapes and positions of ridge's end-points and bifurcation in the fingerprint recognition. but we studied about recognition of polluted fingerprint by chain code ridges. the results and sequence of processing are summarized as follows. (1)Capture several kinds of polluted fingerprint image. (2)Preprocessing(median filtering for removing noises, local and global histogram equalization, dilation and erosion, thinning and remove pseudo image), (3)Rebuild ridge line after Least Square Processing, (4)Compute distribution of chain code vector, (5)The results are almost same values of each vector of preprocessed fingerprint images. From the results, we can surmised more successful fingerprints recognition system in combination with other system by singular points

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.12 no.7
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• pp.3239-3267
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• 2018

Image and video dehazing is a popular topic in the field of computer vision and digital image processing. A fast, optimized dehazing algorithm was recently proposed that enhances contrast and reduces flickering artifacts in a dehazed video sequence by minimizing a cost function that makes transmission values spatially and temporally coherent. However, its fixed-size block partitioning leads to block effects. The temporal cost function also suffers from the temporal non-coherence of newly appearing objects in a scene. Further, the weak edges in a hazy image are not addressed. Hence, a video dehazing algorithm based on well designed spectral clustering is proposed. To avoid block artifacts, the spectral clustering is customized to segment static scenes to ensure the same target has the same transmission value. Assuming that edge images dehazed with optimized transmission values have richer detail than before restoration, an edge intensity function is added to the spatial consistency cost model. Atmospheric light is estimated using a modified quadtree search. Different temporal transmission models are established for newly appearing objects, static backgrounds, and moving objects. The experimental results demonstrate that the new method provides higher dehazing quality and lower time complexity than the previous technique.

• Journal of Construction Engineering and Project Management
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• v.2 no.3
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• pp.1-7
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• 2012

The reconstruction of surfaces from unorganized point clouds can provide very useful information for construction managers. Although point clouds are generally created using 3D scanners, they can also be generated via the structure-from-motion technique using a sequence of images. Here we report a novel surface reconstruction technique for modeling and quantifying earthworks that can be used for preliminary planning, project updates and estimating of earthwork quantities, as well as embedded planning systems in construction equipment. The application of structure-from-motion techniques in earth works is examined and its advantages and limitations identified. Data from 23 earthwork excavation construction sites were collected and analyzed. 3D surface reconstructions during the construction phase were compared to the original land form. Similar experiments were conducted with piles of earth and the results analyzed to determine appropriate ranges of use for structure-from-motion surface reconstructions in earthwork applications. The technique was found to be most suited to pile of materials with volumes less than 2000 m3. Piles up to 10 m in height and with base areas up to $300m^2$ were also successfully reconstructed. These results should be of interest to contractors seeking to utilize new technology to optimize operational efficiency.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.6 no.4
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• pp.1128-1139
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• 2012

With the development of three-dimensional display and related technologies, depth video coding becomes a new topic and attracts great attention from industries and research institutes. Because (1) the depth video is not a sequence of images for final viewing by end users but an aid for rendering, and (2) depth video is simpler than the corresponding color video, fast algorithm for depth video is necessary and possible to reduce the computational burden of the encoder. This paper proposes a fast mode decision algorithm for depth video coding based on depth segmentation. Firstly, based on depth perception, the depth video is segmented into three regions: edge, foreground and background. Then, different mode candidates are searched to decide the encoding macroblock mode. Finally, encoding time, bit rate and video quality of virtual view of the proposed algorithm are tested. Experimental results show that the proposed algorithm save encoding time ranging from 82.49% to 93.21% with negligible quality degradation of rendered virtual view image and bit rate increment.

• Journal of Broadcast Engineering
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• v.15 no.2
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• pp.280-289
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• 2010

The H.264/AVC standard uses efficient inter prediction technologies improving the coding efficiency by reducing temporal redundancy between images. However, since H.264/AVC does not efficiently encode a video sequence that occurs a local illumination change, the coding efficiency of H.264/AVC is decreased when a local illumination change happens in video. In this paper, we propose an improved motion compensation using adjacent pixels and motion vector refinement to efficiently encode local illumination changes. The proposed method always improves the BD-PSNR (Bj$\o$ntegaard Delta Peak Signal-to-Noise Ratio) of 0.01 ~ 0.21 dB compared with H.264/AVC.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2008.10a
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• pp.78-81
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• 2008

The purpose of this research is to verify whether presentation order has an effect on the evaluation of products. In the empirical study, three types of humidifier and those of toaster were used. These products have 6 different sets of combination (3! = 3${\times}$2${\times}$1), and each set was evaluated by 15 subjects who were provided with two sets of images from humidifier and toaster in empirical study (N=90). Subjects completed measures assessing the five aspects: attractiveness, convenience, hygiene, efficiency and durability of the product. Each of the dependent measures was assessed on Likert-scale ranging 1 to 7. The ratings to the five aspects were added individually. Three types of humidifier and those of toaster were divided into 3 classes in terms of 'class A' which consists of the highest rated product, 'class C' which consists of the lowest rated product, and 'class B' which consists of the rest. Two main findings were discovered: First, the presentation order of both class A and class C influences the product evaluation whereas that of class B does not. As class A was presented as the last one, the subjects evaluated it the most positive. In the case of class C, on the contrary, when it is presented as the first is the best for itself; Secondly, the result shows that presented C-B-A sequence combination has a greater effect on entire evaluation than all other conditions in this study.

• Journal of the Institute of Convergence Signal Processing
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• v.15 no.4
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• pp.128-134
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• 2014

In this paper, we propose a detection method of the leukocyte motions in a microvessel by using spatiotemporal image analysis. The leukocyte motions that adhere to blood vessel walls can be visualized to move along the blood vessel wall's contours in a sequence of images. In this proposal method, we use the constraint that the leukocytes move along the blood vessel wall's contours and detect the leukocyte motions by using the spatiotemporal image analysis method. The generated spatiotemporal image is processed by a special-purpose orientation-selective filter and then subsequent grouping processes are done. The subsequent grouping processes select and group the leukocyte trace segments among all the segments obtained by simple thresholding and skeletonizing operations. Experimental results show that the proposed method can stably detect the leukocyte motions even when multiple leukocyte traces intersect each other.

• The Bulletin of The Korean Astronomical Society
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• v.36 no.2
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• pp.70.1-70.1
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• 2011

We have investigated properties of merging galaxies in the nearby universe, using Sloan Digital Sky Survey (SDSS) DR7. We first constructed two galaxy samples according to redshift range: Sample 1 for 0 ${\leq}$ z ${\leq}$ 0.025 and Sample 2 for 0.09 ${\leq}$ z ${\leq}$ 0.1. We then identified 118 and 184 merging galaxies among the galaxies in the Sample 1 and 2, respectively, and classified them into different merging types and stages by visual inspection of galaxy images. In the Sample 1, there are more wet mergers than dry mergers, while most merging galaxies in the Sample 2 are dry mergers. The color-magnitude diagram of the merging galaxies in our samples is comparable to that of normal galaxies. Dry mergers tend to locate in the red sequence, while wet and mixed mergers reside mostly in the blue cloud. Unlike some previous studies, we did not find a clear trend that the merger rate increases at higher redshift. However, it is difficult to make a direct comparison of the merger rate found in different studies, because it depends on the number of observed galaxies and criteria for merger classification. From the ratios of emission lines, we infer that the faction of merging galaxies with AGNs is higher in wet mergers than in other types.