• Korean Journal of Radiology
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• v.21 no.5
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• pp.561-571
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• 2020

Objective: To evaluate the clinical utility of ultrafast dynamic contrast-enhanced (DCE)-MRI compared to conventional DCE-MRI by studying lesion conspicuity and size according to the level of background parenchymal enhancement (BPE). Materials and Methods: This study included 360 women (median age, 54 years; range, 26-82 years) with 361 who had undergone breast MRI, including both ultrafast and conventional DCE-MRI before surgery, between January and December 2017. Conspicuity was evaluated using a five-point score. Size was measured as the single maximal diameter. The Wilcoxon signed-rank test was used to compare median conspicuity score. To identify factors associated with conspicuity, multivariable logistic regression was performed. Absolute agreement between size at MRI and histopathologic examination was assessed using the intraclass correlation coefficient (ICC). Results: The median conspicuity scores were 5 at both scans, but the interquartile ranges were significantly different (5-5 at ultrafast vs. 4-5 at conventional, p < 0.001). Premenopausal status (odds ratio [OR] = 2.2, p = 0.048), non-mass enhancement (OR = 4.1, p = 0.001), moderate to marked BPE (OR = 7.5, p < 0.001), and shorter time to enhancement (OR = 0.9, p = 0.043) were independently associated with better conspicuity at ultrafast scans. Tumor size agreement between MRI and histopathologic examination was similar for both scans (ICC = 0.66 for ultrafast vs. 0.63 for conventional). Conclusion: Ultrafast DCE-MRI could improve lesion conspicuity compared to conventional DCE-MRI, especially in women with premenopausal status, non-mass enhancement, moderate to marked BPE or short time to enhancement.

• Journal of Digital Convergence
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• v.10 no.3
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• pp.173-178
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• 2012

In this paper, a new saliency map generation method is discussed which extracts objects effectively using extracted Salient Region. Feature map is constructed first using four features of edge, hue of HSV color model, focus and entropy and then conspicuity map is generated from Center Surround Differences using the feature map. Final saliency map is constructed by the combination of conspicuity maps. Saliency map generated using this procedure is compared to the conventional technique and confirmed that new technique has better results.

• Journal of the Korean Society for Precision Engineering
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• v.25 no.2
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• pp.131-139
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• 2008

This paper presents a new saliency map which is constructed by providing dynamic weights on individual features in an input image to search ROI(Region Of Interest) or FOA(Focus Of Attention). To construct a saliency map on there is no a priori information, three feature-maps are constructed first which emphasize orientation, color, and intensity of individual pixels, respectively. From feature-maps, conspicuity maps are generated by using the It's algorithm and their information quantities are measured in terms of entropy. Final saliency map is constructed by summing the conspicuity maps weighted with their individual entropies. The prominency of the proposed algorithm has been proved by showing that the ROIs detected by the proposed algorithm in ten different images are similar with those selected by one-hundred person's naked eyes.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.5D
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• pp.437-444
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• 2012

This study intended to improve traffic safety in work zones using fluorescent orange color traffic signs. For this end, the current problems of existing traffic signs and facilities in work zones were analyzed and some good examples of foreign countries were compared. More specifically, in order to identify current problems, the basic shape and color of traffic signs in use were examined through literature review, surveys and field studies. It was found that the fluorescent color worked more effectively than other colors in terms of visibility and conspicuity in work zone sign system. For evaluation, both Conspicuity surveys and in-door simulator experiments were conducted to effectively assess the merits and demerits of different types of traffic signs for work zones. The results of evaluations showed that black lettering on a fluorescent orange background outperformed more than 70% in terms of visibility and ability to call drivers' attention compared with those from black/red lettering on yellow/white backgrounds currently used at work zones on expressways and national highways. In addition, simulated driving experiment disclosed that drivers recognized the fluorescent orange background sign 15m ahead compared with the yellow background sign and 25m ahead compared with the white background sign, respectively. As for the diamond-shaped "Under Construction" sign, drivers recognized fluorescent orange background 11m ahead compared with the yellow background sign and 19m ahead compared with the white background sign, respectively.

• Korean Journal of Radiology
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• v.22 no.4
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• pp.502-512
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• 2021

Objective: To objectively and subjectively assess and compare the characteristics of monoenergetic images [MEI (+)] and polyenergetic images (PEI) acquired by dual-energy CT (DECT) of patients with breast cancer. Materials and Methods: This retrospective study evaluated the images and data of 42 patients with breast cancer who had undergone dual-phase contrast-enhanced DECT from June to September 2019. One standard PEI, five MEI (+) in 10-kiloelectron volt (keV) intervals (range, 40-80 keV), iodine density (ID) maps, iodine overlay images, and Z effective (Z_eff) maps were reconstructed. The contrast-to-noise ratio (CNR) and the signal-to-noise ratio (SNR) were calculated. Multiple quantitative parameters of the malignant breast lesions were compared between the arterial and the venous phase images. Two readers independently assessed lesion conspicuity and performed a morphology analysis. Results: Low keV MEI (+) at 40-50 keV showed increased CNR and SNR_{breast lesion} compared with PEI, especially in the venous phase ([CNR: 40 keV, 20.10; 50 keV, 14.45; vs. PEI, 7.27; p < 0.001], [SNR_{breast lesion}: 40 keV, 21.01; 50 keV, 16.28; vs. PEI, 10.77; p < 0.001]). Multiple quantitative DECT parameters of malignant breast lesions were higher in the venous phase images than in the arterial phase images (p < 0.001). MEI (+) at 40 keV, ID, and Z_eff reconstructions yielded the highest Likert scores for lesion conspicuity. The conspicuity of the mass margin and the visual enhancement were significantly better in 40-keV MEI (+) than in the PEI (p = 0.022, p = 0.033, respectively). Conclusion: Compared with PEI, MEI (+) reconstructions at low keV in the venous phase acquired by DECT improved the objective and subjective assessment of lesion conspicuity in patients with malignant breast lesions. MEI (+) reconstruction acquired by DECT may be helpful for the preoperative evaluation of breast cancer.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.44 no.1
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• pp.50-58
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• 2007

In this paper, we propose a query-based visual attention algorithm for effective object finding of a vision-based mobile robot. This algorithm is developed by extending conventional bottom-up visual attention algorithms. In our proposed algorithm various conspicuity maps are merged to make a saliency map, where weighting values are determined by query-dependent object properties. The saliency map is then used to find possible attentive location of queried object. To show the validities of our proposed algorithm, several objects are employed to compare performances of our proposed algorithm with those of conventional bottom-up approaches. Here, as one of exemplar query-dependent object property, color property is used.

• Journal of Families and Better Life
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• v.30 no.3
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• pp.105-118
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• 2012

This study aims to recognize cognition of credit card and shopping value in contemporary society, cognition of credit card and shopping value according to types of consumption orientation, and factors that influence cognition of credit card and shopping value, and ultimately provide a foundation for establishing proper shopping value. A total of 453 women and men residing in Seoul have been set as research object in order to achieve the purpose of the study. The data was analyzed by Cronbach' alpha, frequencies, percentile, mean, factor analysis, K-mean cluster analysis, t-test, ANOVA and Duncan's multiple range test, multiple linear regression. All analysis progress was done by spsswin12.0 statistics program. A summary of this research goes as follows: First, categorization of consumption orientation lead to two clusters of rational and symbolic & conspicuity consumption patterns and cognition of credit card was categorized into positive and negative cognition and shopping value was categorized into hedonic shopping value, utilitarian shopping value and time-save shopping value. Second, rational shoppers had high utilitarian shopping values and symbolic & conspicuity shoppers had high both hedonic shopping values and utilitarian shopping values. Third, the most influential factor in hedonic shopping value and utilitarian was consumption orientation. In conclusion, this research has showed that cognition of credit card and shopping value according to types of consumption orientation patterns varied, and that consumption orientation was an influential factor on cognition of credit card and shopping value.

• International Journal of Highway Engineering
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• v.8 no.4 s.30
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• pp.1-11
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• 2006

Currently, road mobility improved from the National Road Improvement. Nevertheless delineation system is facility that enhanced driver's safety, that was set up often inconsistent or nonexistent over the road exit ramp So it judged functional investigation will be necessary. This study suggested setting type of the delineation system. That was based on a field study and reviews the legal standard of it and considering driver's cognition behavior. For the study, make a 3D-simulation and so could objectively a comparative test. Comparison variable between delineation setting type is selected conspicuity and visibility. Cased that illustrated characteristics of driver's visual cognition behavior. The experiment was used Eye Marker Recorder for measure the gaze frequency more quantitatively and objectively. And used the ANOVA analysis for significance testing between delineation setting type. A significant percent of the conspicuity analyzed types(Safe mark, Obstacle Sign, Warning Light, and Tubular Maker) in road exit ramp for recognize. And gaze frequency that measure of effectiveness of visibility are measured. On the analysis result, the visibility was significance difference between delineation setting type and visibility of types was best.

• Investigative Magnetic Resonance Imaging
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• v.3 no.1
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• pp.60-65
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• 1999

Purpose : The purpose of this study was to evaluate the image quality, contrast characteristics, and possible clinical utility of Medium Tau Inversion Recovery(MTIR) sequence with white matter suppression in patients with brain cortical lesion. Materials and methods : Two normal volunteers and twenty-one patients with cortical lesion were scanned with MTIR as well as other MR imaging sequences. Gray-white matter contrast was evaluated objectively using region-of-interest calculations, including percent contrast and contrast-to-noise ratio(CNR). MTIR sequence was visually compared with other sequences in 21 patients with cortical lesion including conspicuity and detection rate. Results : MTIR sequence had the highest present contrast and CNR between the gray matter and white matter. In twenty-one cases of cortical lesion including cortical dysplasia, MTIR sequence improved delineation and conspicuity of lesion, but MTIR sequence could not detect new lesions. Conclusion : The MTIR sequence well delineated the cortical lesions, particularly in including cortical dysplasia. It may be used as an adjunctive imaging sequence in case of poor gray and white matter differentiation with conventional T1-weighted sequences.

• The Journal of the Korea Contents Association
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• v.6 no.1
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• pp.41-53
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• 2006

In this paper, an adaptive ROI(region of interest) detection system for spatialtemporal features is proposed. It utilizes spatiotemporal features for the purpose of detecting ROI. It is assumed that motion representing temporal visual conspicuity between adjacent frames takes higher priority over spatial visual conspicuity. Because objects or regions in motion usually draw stronger attention than others in motion pictures. In case of still images visual features that constitute topographic feature maps are used as spatial features. Comparative experiments with a human subjective evaluation show that correct detection rate of visual attention region is improved by exploiting both spatial and temporal features compared to the case of exploiting either feature.